CN102116289A

CN102116289A - Vane pump

Info

Publication number: CN102116289A
Application number: CN2010101578078A
Authority: CN
Inventors: 饭岛正昭
Original assignee: Hitachi Automotive Systems Ltd
Current assignee: Hitachi Astemo Ltd
Priority date: 2010-01-05
Filing date: 2010-03-31
Publication date: 2011-07-06
Also published as: JP2011157954A; US20110165010A1; JP5395713B2

Abstract

A vane pump includes: a rotor with slots; vanes mounted in the slots, and adapted to project from the slots; a cam ring surrounding the rotor; and a plate defining pump chambers in cooperation with the rotor, vanes and cam ring. The plate includes: a suction port; a discharge port; a first back pressure port that receives a suction-side fluid pressure, and hydraulically communicates with a first back pressure chamber corresponding to a first vane positioned in a suction region; and a second back pressure port that hydraulically communicates with a second back pressure chamber corresponding to a second vane whose distal end portion is positioned at a terminal end portion of the suction port. The second back pressure port includes: a first portion arranged to receive a discharge-side fluid pressure; and a throttling portion for restricting a fluid flow between the first portion and second back pressure chamber.

Description

Vane pump

Technical field

The present invention relates to vane pump.

Background technique

Japanese Patent Application Publication No.7-259754 discloses a kind of variable displacement vane pump, and it comprises: rotor, this rotor are included in a plurality of slits of its periphery; A plurality of blades, these blade installation and are used for protruding and advancing to the inboard and the outside of this respective slots from respective slots in a corresponding slit; Cam ring, this cam ring be with respect to rotor eccentricity, this cam ring surrounding rotor; And a plurality of pump chambers, these pump chambers are determined by the interior perimeter surface of blade, cam ring and the outer surface of rotor, pump delivery along with cam ring with respect to the variation of the eccentricity of rotor and change.Vane pump is arranged to like this, when the distal portions of blade is arranged in suction zone or discharging area, the proximal part of blade is applied with back pressure, this back pressure equals to be applied to the pressure of distal portions substantially, reduce resistance when on the interior perimeter surface of cam ring, sliding, and therefore reduce the power loss of drive vane pump the blade distal portions with convenient blade.Be arranged in before blade is entering discharging area when sucking the zone, the proximal part of blade begins to be applied in discharge side liquid pressure (high pressure).Even this will guarantee that blade also protrudes from slit, so that seal pump chamber well, thereby makes the pump proper functioning when vane pump (under this low temperature, the viscosity of working fluid is higher relatively) when operation at low temperatures.

Summary of the invention

The problem that this vane pump described in Japanese Patent Application Publication No.7-259754 may run into is because multiple factor (for example contact between parts) produces noise.Therefore, be desirable to provide a kind of vane pump that can suppress noise.

According to an aspect of the present invention, a kind of vane pump comprises: rotor, and this rotor is used for rotating by live axle, and rotor is included in a plurality of slits of its periphery; A plurality of blades, these blade installation and are used for protruding and advancing to the inboard and the outside of this respective slots from corresponding slit in corresponding slit; Cam ring, this cam ring be with respect to rotor eccentricity, this cam ring surrounding rotor; And plate, this plate is arranged to the axial end portion towards rotor, and cooperate with rotor, blade and cam ring and to determine a plurality of pump chambers, wherein, this plate comprises in the side facing to rotor: suction port, this suction port is opened on and sucks in the zone, sucks in the zone at this, and each pump chamber expands when moving together along with the rotation of rotor gradually; Exhaust port, this exhaust port is opened in the discharging area, and in this discharging area, each pump chamber shrinks when moving together along with the rotation of rotor gradually; The first back pressure mouth, this first back pressure mouth is arranged to receive the suction side hydrodynamic pressure, and with proximal part hydraulic communication corresponding at least the first slit that sucks first blade in the zone; And the second back pressure mouth, this second back pressure mouth is arranged to and proximal part hydraulic communication corresponding at least the second slit of second blade, and the distal portions of this second blade is positioned at the terminal part office of suction port; Wherein, the second back pressure mouth comprises: first portion, this first portion are arranged to receive discharge side liquid pressure; And the throttling part, the fluid that this restriction branch is arranged to be limited between the proximal part of the first portion and second slit flows.

Description of drawings

Fig. 1 is the skeleton diagram of expression stepless speed variator (CVT) system, and the vane pump of various embodiments of the present invention is used for this system.

Fig. 2 is the partial sectional view of the vane pump of first embodiment of the invention at the axial direction of the situation lower edge rotor of removing side panel.

Fig. 3 is the planimetric map of first plate of vane pump.

Fig. 4 is the sectional view of first plate along the line IV-IV among Fig. 3.

Fig. 5 is the sectional view of first plate along the line V-V among Fig. 3.

Fig. 6 is the sectional view of the part of vane pump, comprises the sectional view of first plate along the line VI-VI among Fig. 3.

Fig. 7 is the enlarged view of the part represented by the VII among Fig. 6, and the section shape of the starting end part of side back pressure mouth is discharged in expression.

Fig. 8 is the sectional view of vane pump along the line VIII-VIII among Fig. 6.

Fig. 9 is illustrated in the cross-sectional flow area of the starting end part of discharging side back pressure mouth and the plotted curve of the relation between peripheral length and the noise level.

Figure 10 is the sectional view of the vane pump of first comparison example, and it is corresponding with the sectional view of Fig. 8.

Figure 11 is the sectional view of the vane pump of second comparison example, and it is corresponding with the sectional view of Fig. 8.

Figure 12 A to 12D is the planimetric map according to the starting end part of the discharge side back pressure mouth of the version of second embodiment of the invention.

Figure 13 A and 13B are the sectional side views according to the starting end part of the discharge side back pressure mouth of second embodiment's version.

Figure 14 A to 14D is the planimetric map according to the starting end part of the discharge side back pressure mouth of the version of third embodiment of the invention.

Figure 15 is the sectional side view according to the starting end part of the discharge side back pressure mouth of the 3rd embodiment's version.

Embodiment

First embodiment/structure

Introduce the structure of the vane pump (back is called pump 1) of first embodiment of the invention below.Pump 1 is used for providing hydraulic pressure to the hydraulic actuator of motor vehicle.In this embodiment, pump 1 is used for providing hydraulic pressure to variable v-belt drive (CVT 100).Pump 1 is not such restriction, but can be used for providing hydraulic pressure to other hydraulic actuator, for example the hydraulic actuator in power steering system.Pump 1 is driven by the bent axle of internal-combustion engine, so that suck and discharge working fluid.In this example, working fluid is a working oil, for example ATF (automatic transmission fluids).Typical A TF has less relatively Young's modulus, and like this, the smaller size smaller of ATF changes the variation in pressure that can cause greatly.Fig. 1 has represented the system of CVT 100, and pump 1 is used for this system.CVT 100 comprises control valve unit 200, this control valve unit 200 provides various valves, for example kickdown valve 201, Auxiliary valves 202, aux. pressure solenoid valve 203, line pressure solenoid valve 204, pressure regulator valve 205, manually operated valve 206, locking/selector switch solenoid valve 207, clutch and regulating valve 208, selection control valve 209, locking solenoid valve 210, torque converter modulating valve 211, locking control valve 212 and selector switch valve 213.These valves are controlled by CVT control unit 300.Working fluid is discharged and supplied with to pump 1 by control valve unit 200 to each parts of CVT 100, and each parts of CVT 100 for example are head pulley 101, auxiliary pulley 102, to front clutch 103, plugging device 104, torque converter 105 and lubricated and cooling system 106.

Fig. 2 is the partial sectional view of pump 1 at the axial direction of the situation lower edge rotor 6 of removing side panel.In the following description, three-dimensional normal coordinates system is assumed to like this, and wherein, the x axis is defined as extending along the radial direction of pump 1, and the y axis is defined as extending along another radial direction of pump 1, and the z axis is defined as extending along the axial direction of rotor 6.Specifically, the x axis is defined as extending along such direction, and wherein, the central axis of cam ring 8 " P " moves in the direction with respect to the spin axis " O " of rotor 6 or swings.The y axis is defined as edge and all vertical direction extension of x axis and z axis.Fig. 2 has represented along the view from the negative z side direction of positive z side direction.In Fig. 2, positive x axial direction is the central axis P of cam ring 8 direction that departs from spin axis O (perhaps from the direction of second closed area RE4 to the first closed area RE3, as hereinafter described with shown in Fig. 3).In Fig. 2, positive y axial direction is from sucking the direction of zone towards discharging area.

Pump 1 is the variable displacement type, can change its discharge capacity or discharge capacity or pumping capacity, the Fluid Volume that promptly whenever turns around and discharge.Pump 1 comprises: pumping part 2 is used for sucking and discharging working fluid; And control section 3, being used to control the discharge capacity, they are integrated into a unit.Pumping part 2 is contained in the housing 4, and this pumping part 2 comprises live axle 5, rotor 6, blade 7 and cam ring 8.Housing 4 comprises enclosure body 40, first plate 41 and second plate 42, and they for example are fixed together by bolt.

Enclosure body 40 is formed with basic cylindricality through hole 400, and this through hole 400 extends along the z axial direction, and the adapter ring 9 of annular is installed in this through hole 400.Adapter ring 9 comprises the receiving bore 90 of basic cylindricality, and this receiving bore 90 extends along the z axial direction.Receiving bore 90 is formed with first flat section 91, and this first flat section 91 is positioned at positive x side, and is basically parallel to the y-z plane.Receiving bore 90 also is formed with second flat section 92, and this second flat section 92 is positioned at negative x side, and is basically parallel to the y-z plane.Second flat section 92 is formed with recess 920, and this recess 920 is positioned at the center position of second flat section 92 substantially along the z axial direction, and extends along negative x axial direction.Receiving bore 90 also is formed with the 3rd flat section 93, the three flat sections 93 and is positioned at positive y side, and with respect to spin axis O a little in positive x side, and be basically parallel to the z-x plane.The 3rd flat section 93 is formed with groove or recess 930, and when when the z axial direction is seen, this groove or recess 930 have semi-circular cross-section.The 3rd flat section 93 also is formed with first and second communication passage 931 and 932 in recess 930 both sides.Specifically, first communication passage 931 is opened in a part positive x side of recess 930, the 3rd flat section 93, and second fluid passage 932 is opened in the part negative x side, the 3rd flat section 93 of recess 930.Receiving bore 90 also is formed with the 4th flat section 94, the four flat sections 94 and is positioned at negative y side, is basically parallel to the z-x plane.The 4th flat section 94 is formed with groove or recess 940, and when when the z axial direction is seen, this groove or recess 940 have the rectangular cross-section.

Cam ring 8 is installed in the receiving bore 90 of adapter ring 9, is suitable for unrestricted motion or swing, and wherein, cam ring 8 has annular shape.Therefore, adapter ring 9 is arranged to surround cam ring 8.When the z axial direction is seen, cam ring 8 has perimeter surface 80 and basic circular outer peripheral surface 81 in the basic circle, and wherein, cam ring 8 has basic radial thickness uniformly.The outer surface 81 of cam ring 8 is formed with groove or recess 810, and when when the z axial direction is seen, groove or recess 810 have semi-circular cross-section, and wherein, recess 810 is positioned at the positive y side of outer surface 81.The outer surface 81 of cam ring 8 also is formed with basic cylindricality recess 811, and this basic cylindricality recess 811 has the central longitudinal axis that extends along the x axial direction, and wherein, recess 811 is positioned at the negative x side of outer surface 81.Pin 10 is installed between the recess 810 in the periphery of recess 930 in interior week of adapter ring 9 and cam ring 8, and this pin extends along the z axial direction, and is assemblied in the space that is determined between recess 930 and 810.Sealing 11 is installed in the recess 940 in the periphery of adapter ring 9.The negative y side contacts of the outer surface 81 of Sealing 11 and cam ring 8.For example spring 12 of elastic member is provided, and this elastic member has the vertical end in the recess 920 in the interior week that is installed in adapter ring 9.Spring 12 is wind springs.Another of spring 12 vertically end is installed in the recess 811 of cam ring 8.Spring 12 is mounted to compressive state, so that push cam ring 8 with respect to adapter ring 9 or housing 4 along positive x axial direction always.Receiving bore 90 is arranged to bigger than the diameter of the outer surface 81 of cam ring 8 along the size (i.e. distance between first flat section 91 and second flat section 92) of x axial direction.Cam ring 8 is bearing on the 3rd flat section 93 by adapter ring 9 or housing 4, and the 3rd flat section 93 that is used for making to fulcrum moves on the x-y plane or swing.Pin 10 is used to limit cam ring 8 with respect to the skew of adapter ring 9 or rotation relatively.

The swing of cam ring 8 limits by the contact between first flat section 91 at outer surface 81 and adapter ring 9 in positive x side, and limits by the contact between second flat section 92 at outer surface 81 and adapter ring 9 in negative x side.The central axis P of cam ring 8 is represented by δ with respect to eccentricity or the distance of spin axis O.When the outer surface 81 of cam ring 8 contacted with second flat section 92 of adapter ring 9, the central axis P of cam ring 8 was positioned at spin axis O place substantially, and like this, the eccentricity delta is approximately equalled zero.This position is called minimum eccentric position.On the other hand, when the outer surface 81 of cam ring 8 contacts with first flat section 91 of adapter ring 9, eccentricity delta's maximum.This position is called the maximum eccentric position.When cam ring 8 swings, the 3rd flat section 93 of adapter ring 9 and outer surface 81 sliding contacts of cam ring 8, Sealing 11 and outer surface 81 sliding contacts in recess 940.The positive z side and the negative z side in the space between the periphery of interior week of adapter ring 9 and cam ring 8 seal by first plate 41 and second plate 42 respectively, and by the 3rd flat section 93 and Sealing 11 and fluid-tight or liquid seal ground are divided into first and second control chamber R1 and the R2.The first control chamber R1 is positioned at positive x side, and the second control chamber R2 is positioned at negative x side.First control chamber R1 and first communication passage, 931 hydraulic communication, and second control chamber R2 and second communication passage, 932 hydraulic communication.Under the situation of the limitation of movement system of cam ring 8, between the interior week of the periphery of cam ring 8 and adapter ring 9, provide the gap, like this, the first and second control chamber R1 and R2 cubical content separately are always greater than zero.

Live axle 5 is rotatably mounted by first and second plates 41 and 42 of housing 4.Live axle 5 is connected with the bent axle of internal-combustion engine by timing chain, and like this, live axle 5 rotates synchronously with bent axle.Rotor 6 is arranged coaxially with live axle 5, and is connected with the periphery of live axle 5 by the spline link.Rotor 6 has basic cylindrical shape, and is installed in cam ring 8 inboards.Therefore, cam ring 8 is arranged to surrounding rotor 6.Like this, annular cavity R3 is determined between the outer surface 60 of the interior perimeter surface 80 of cam ring 8 and rotor 6, and between first and second plates 41 and 42.Rotor 6 rotates around spin axis O with live axle 5 as shown in Figure 2 along clockwise direction.

Rotor 6 is formed with a plurality of slits 61, and these slits 61 are along the radially extension of rotor 6.When the z axial direction is seen, each slit 61 extends predetermined depth point-blank along the radial direction of rotor 6 from outer surface 60 towards spin axis O, and extends on the whole length of rotor 6 along the z axial direction.11 slits 61 are arranged along circumferential direction, and are opened evenly.11 blades 7 are provided, and each blade 7 is the plate of basic rectangle, and is installed in the corresponding slit 61, is used for advancing from slit 61 protrusions and to the inboard and the outside of this slit 61.When the z axial direction is seen, the distal portions 70 of blade 7 (this distal portions 70 along the radial direction of rotor 6 in the outside, or further from the end sections of spin axis O) bending so that cooperate with the interior perimeter surface 80 of cam ring 8.The number of slit 61 or blade 7 is not limited to 11.When the z axial direction is seen, the proximal part 610 of slit 61 (this proximal part 610 along the radial direction of rotor 6 in the inboard, or the longitudinal end branch of more close spin axis O) forms basic cylindrical shape, wherein, the diameter of this cylindrical shape is greater than the main body 611 of slit 61 size along the circumferential direction of rotor 6.The shape of proximal part 610 is not limited to cylindrical shape, but can form rectangular shape, and is similar with this main body 611.The proximal part 610 of slit 61 and the proximal part 71 of blade 7 (this proximal part 71 along the radial direction of rotor 6 in the inboard, or the longitudinal end branch of more close spin axis O) between determined pressure receiving part or back pressure chamber " br ".The outer surface 60 of rotor 6 is formed with a plurality of protruding 62, and each projection is positioned at corresponding blade 7 places, and when basic trapezoid cross section is arranged when the z axial direction is seen.Projection 62 is extended on the whole length of rotor 6 along the z axial direction, and stretches out predetermined altitude along the radial direction of rotor 6 from outer surface 60.When the z axial direction is seen, slit 61 is opened on the center of projection 62 substantially.Slit 61 is arranged to equal substantially the length of blade 7 along the radial direction of rotor 6 along the length (total length that promptly comprises proximal part 610 and projection 62) of the radial direction of rotor 6.Even it is to be used for for example closing region R E3 first when blade 7 to go out also to keep blade 7 from slit 61 is maximum slit 61 when protruding that projection 62 is provided always.In other words, this structure is used for removing unwanted part (except projection 62) from the outer surface 60 of rotor 6, guarantees that simultaneously this slit 61 keeps blade 7 always.This causes the cubical content of pump chamber " r " to increase, pump efficiency increases, the weight of rotor 6 reduces to reduce with power loss.

Annular cavity R3 between rotor 6 and cam ring 8 is divided into 11 pump chamber r by 11 blades 7.Hereinafter, the distance definition of sense of rotation (clockwise direction among Fig. 2 is represented by RD1) between two adjacent blades 7 along rotor 6 is unit pitch.Pump chamber r equals a pitch along the length of rotor sense of rotation RD1, and does not change.When the central axis P of cam ring 8 along positive x axial direction from spin axis O displacement or when eccentric, along the distance (perhaps pump chamber r along the size of rotor radial direction) of rotor radial direction between the interior perimeter surface 80 of the outer surface 60 of rotor 6 and cam ring 8 along with increasing gradually from negative x side to positive x side.Therefore, greater than the cubical content of pump chamber r in negative x side, wherein, advance to the inboard and the outside of slit 61 along the dimensional changes of rotor radial direction according to pump chamber r by blade 7 at the cubical content of positive x side for pump chamber r.Therefore, in the zone of the negative y side of x axis, when in company with rotor 6 during along the rotation of rotor sense of rotation RD1 (along the clockwise direction among Fig. 2) and from the positive x lateral movement of negative x side direction, the cubical content of pump chamber r increases gradually.On the other hand, in the zone of the positive y side of x axis, when in company with rotor 6 during along the rotation of rotor sense of rotation RD1 (along the clockwise direction among Fig. 2) and from the negative x lateral movement of positive x side direction, the cubical content of pump chamber r reduces gradually.

First and second plates 41 and 42 are a pair of dished plate (pressure plate or side panel).First and second plates 41 and 42 are arranged to two axial ends towards rotor 6 (with blade 7) and cam ring 8 along the z axial direction, and its rotor 6 (and blade 7) and cam ring 8 are clipped between first and second plates.First plate 41 is arranged to towards the negative z side of rotor 6 and other parts.Fig. 3 has represented the planimetric map of first plate 41 when positive z side sees.The profile line of first plate 41 schematically illustrates to round-shaped, and omits bolt hole etc.Fig. 4 is the sectional view of first plate 41 along the line IV-IV among Fig. 3.Fig. 5 is the sectional view of first plate 41 along the line V-V among Fig. 3.Pump cover 49 is arranged in the negative z side of first plate 41.Fig. 5 has represented the sectional view of pump cover 49.Pump cover 49 is formed with through hole 490, first communication passage 491 and second communication passage 492.Live axle 5 inserts and is rotatably supported in this through hole 490.First communication passage 491 is the form of groove, being used for the suction side is communicated with, this first communication passage 491 is formed in the positive z side surface of pump cover 49, and is positioned to overlap with the intercommunicating pore 451 of first plate 41 and the negative z side opening of intercommunicating pore 432 (they will be described in detail below).The positive z side surface of pump cover 49 also is formed with seal groove 494, and it is around second communication passage 492.O shape ring 496 is installed in the seal groove 494, is used for sealing.Be arranged under the situation of the positive z side surface of pump cover 49 at the negative z side surface of first plate 41, O shape ring 496 is compressed into the negative z side surface of first plate 41 along the z axial direction and closely contacts, so that improve the liquid seal of second communication passage 492 that is subjected to high pressure.

First plate 41 is formed with suction port 43, exhaust port 44, suction side back pressure mouth 45, discharges side back pressure mouth 46, pin-and-hole 47 and through hole 48.Pin 10 inserts and is fixed in the pin-and-hole 47.Live axle 5 inserts and is rotatably supported in the through hole 48.Second plate 42 is formed with similar mouthful and hole in similar position.But, the mouth of second plate 42 can omit.In first embodiment, first and second plates 41 and 42 all are formed with so similar mouthful structure and will be used for balance effectively and be applied to hydraulic coupling on rotor 6 and the blade 7 from exhaust port 44 etc. along the z axial direction, thereby suppress owing to unevenly contact tearing and resistance of causing.Also can select, suction port 43 grades can be distributed on first and second plates 41 and 42 suitably.

Suction port 43 is arranged in the suction zone or part RE1 of negative y side of first plate 41, sucks among zone or the part RE1 at this, and pumping r expands when moving along with the rotation of rotor 6 gradually.Working fluid is arranged in the pump chamber r that sucks regional RE1 by suction port 43 from outside supply.Suction port 43 comprises suction side curve bath 430, inlet hole 431 and intercommunicating pore 432.Suction side curve bath 430 is formed in the positive z side surface 410 of first plate 41, and is arranged to receive the suction side hydrodynamic pressure.When the z axial direction is seen, suction side curve bath 430 is the arcuate shape around spin axis O, is passed in along the circumferential direction of first plate 41 to suck the part of arranging pump chamber r among the regional RE1 and extend.The suction of pump 1 zone RE1 by the angular range of suction side curve bath 430 (promptly by connect spin axis O and suction side curve bath 430 at the straight line of the beginning end points " A " of the negative x side of first plate 41 and is connected spin axis O and angle [alpha] that suction side curve bath 430 is determined at the straight line of the terminal point " B " of the positive x side of first plate 41) come definite.In this example, this angle [alpha] equals about 4.5 times of pitches.The beginning terminal A of suction side curve bath 430 and terminal point B are positioned to leave x axis angle beta along negative y axial direction separately, and wherein, in this example, this angle beta equals about 0.5 times of pitch.Suction side curve bath 430 provides the semicircle end portion of protruding along rotor sense of rotation RD1 436.Suction side curve bath 430 provides starting end part 435, this starting end part 435 comprises: major component starting end part 433, this major component starting end part 433 have the semicircular in shape of protruding along the direction (being called rotor counterrotating direction) opposite with rotor sense of rotation RD1; And groove 434, this groove 434 forms with major component starting end part 433 continuous.Groove 434 433 extends about 0.5 times of pitch to beginning terminal A along rotor counterrotating direction from major component starting end part.Suction side curve bath 430 along even substantially on the whole length of circumferential direction, and equals the width of annular cavity R3 along the rotor radial direction along the width of rotor radial direction substantially when cam ring 8 is in minimum eccentric position, as shown in Figure 2.Suction side curve bath 430 has inboard radial edges 437, and this inboard radial edges 437 is positioned to along the rotor radial direction a little in the outside of the outer surface 60 of rotor 6 (except projection 62).Suction side curve bath 430 has outer radial edge 438, this outer radial edge 438 is positioned to when cam ring 8 is in minimum eccentric position along the rotor radial direction a little in the outside of the interior perimeter surface 60 of rotor 6, and when cam ring 8 is in the maximum eccentric position along the rotor radial direction a little in the outside of the interior perimeter surface 80 of cam ring 8.No matter where cam ring 8 is positioned at, and the pump chamber r in sucking the zone is overlapping with suction side curve bath 430 when the z axial direction is seen, and with suction side curve bath 430 hydraulic communication.Inlet hole 431 is opened on the basic center of suction side curve bath 430 along circumferential direction.Inlet hole 431 has basic elliptical shape when the z axial direction is seen, and equals the width of suction side curve bath 430 substantially along the width of rotor radial direction, and equals an about pitch along the length of circumferential direction.Inlet hole 431 be arranged to when when the z axial direction is seen and the y axis overlap, extend thereby pass first plate 41 along the z axial direction.Intercommunicating pore 432 is opened in the suction side curve bath 430, and is arranged to contiguous inlet hole 431 and leaves inlet hole 431 (than inlet hole 431 more close beginning terminal A) along rotor counterrotating direction.Intercommunicating pore 432 has and inlet hole 431 similar shapes, passes first plate 41 along the z axial direction and extends.In suction side curve bath 430, major component starting end part 433, the part between intercommunicating pore 432 and inlet hole 431 and be less than or equal to first plate 41 along 20% of the thickness of z axial direction along the degree of depth of the end portion 436 of z axial direction.Part between major component starting end part 433 and intercommunicating pore 432 tilts, and makes the degree of depth increase gradually along rotor sense of rotation RD1, and becomes and equal the thickness of first plate 41 at intercommunicating pore 432 places.Part between inlet hole 431 and end portion 436 tilts, and makes the degree of depth reduce gradually along rotor sense of rotation RD1, and becoming equals major component starting end part 433 degree of depth at part 436 places endways.When the z axial direction is seen, groove 434 acutangulates leg-of-mutton shape, and it increases along rotor sense of rotation RD1 gradually along the width of rotor radial direction.Groove 434 is arranged to width less than suction side curve bath 430 along the Extreme breadth of rotor radial direction.Groove 434 is arranged to along rotor sense of rotation RD1 from zero a few percent that increases to first plate, 41 thickness along the degree of depth of z axial direction.Therefore, the cross-sectional flow area of groove 434 is arranged to the major component less than suction side curve bath 430, and is arranged to increase gradually along rotor sense of rotation RD1, thereby forms the throttling part.

Exhaust port 44 is arranged in the discharging area or part RE2 of positive y side of first plate 41, and in this discharging area or part RE2, pump chamber r shrinks when moving along with the rotation of rotor 6 gradually.Working fluid discharges from the pump chamber r that is arranged in discharging area RE2 by exhaust port 44.Exhaust port 44 comprises discharges side curve bath 440, intercommunicating pore 441 and tap hole 442.Discharge side curve bath 440 and be formed in the positive z side surface 410 of first plate 41, and be arranged to receive discharge side liquid pressure.When the z axial direction is seen, discharge side curve bath 440 and be arcuate shape around spin axis O, be passed in the part extension of arranging pump chamber r among the discharging area RE2 along the circumferential direction of first plate 41.The discharging area RE2 of pump 1 by the angular range of discharging side curve bath 440 (promptly by connect spin axis O and discharge side curve bath 440 at the straight line of the beginning end points " C " of the positive x side of first plate 41 and is connected spin axis O and discharges the angle [alpha] that side curve bath 440 is determined at the straight line of the terminal point " D " of the negative x side of first plate 41) next definite.In this example, this angle [alpha] equals about 4.5 times of pitches.The beginning end points C and the terminal point D that discharge side curve bath 440 are positioned to leave x axis angle beta along positive y axial direction separately, and wherein, in this example, this angle beta equals about 0.5 times of pitch.Discharge side curve bath 440 and provide rectangle starting end part 443.Discharge side curve bath 440 along the width of rotor radial direction along even substantially on the whole length of circumferential direction, and be slightly less than the width of suction side curve bath 430.Discharging side curve bath 440 has inboard radial edges 446, and this inboard radial edges 446 is positioned to along the rotor radial direction a little in the outside of the outer surface 60 (except projection 62) of rotor 6.Discharging side curve bath 440 has outer radial edge 447, and this outer radial edge 447 is positioned to when cam ring 8 is in minimum eccentric position basic consistent with the interior perimeter surface 80 of cam ring 8 along the rotor radial direction.No matter where cam ring 8 is positioned at, and the pump chamber r in discharging area RE2 is seeing that along the z axial direction Shi Douyu discharges side curve bath 440 and overlaps, and with discharge side curve bath 440 hydraulic communication.Tap hole 442 is opened on discharges end portion 444 side curve bath 440, that be arranged in the rotor sense of rotation RD1 side of discharging side curve bath 440.Tap hole 442 has basic elliptical shape when the z axial direction is seen, and equals to discharge the width of side curve bath 440 substantially along the width of rotor radial direction, and along the length of circumferential direction less times greater than a pitch.Tap hole 442 forms along the z axial direction and passes 41 extensions of first plate.Tap hole 442 has semicircular edge, and this semicircular edge protrudes along rotor sense of rotation RD1, and when substantially consistent with the semicircular edge of end portion 444 when the z axial direction is seen.Intercommunicating pore 441 is opened on the rotor counterrotating direction side of discharging side curve bath 440, when it is arranged in the position relative with the position of intercommunicating pore 432 with respect to spin axis O when the z axial direction is seen.The shape of intercommunicating pore 441 and tap hole 442 are similar,, pass first plate 41 along the z axial direction and extend for being approximately a pitch along the length of circumferential direction.The starting end part 443 of discharging side curve bath 440 is stretched to the rotor counterrotating direction side margin 445 of intercommunicating pore 441 from beginning end points C.Rotor counterrotating direction side margin 445 is becoming the semicircular in shape of protruding along rotor counterrotating direction when the z axial direction is seen, and has forward terminal " E ", this forward terminal " E " to be positioned at along rotor sense of rotation RD1 to leave the about pitch place of top point C.When the z axial direction is seen, starting end part 443 front edges suction side curve bath 430, along rotor counterrotating direction towards terminal point B form point-blank and extend along the rotor radial direction.In discharging side curve bath 440, the degree of depth of the major component 448 between intercommunicating pore 441 and tap hole 442 (along the z axial direction) equals first plate 41 along about 25% of the thickness of z axial direction.Starting end part 443 is along the degree of depth of the z axial direction degree of depth less than major component 448, and changes along with the rotor counterrotating direction side margin 445 from beginning end points C to intercommunicating pore 441.Specifically, starting end part 443 equals zero in the degree of depth at beginning end points C place, and be arranged to increase gradually about 10% of the thickness that is less than or equal to first plate 41 of becoming at rotor counterrotating direction side margin 445 places towards rotor counterrotating direction side margin 445.The cross-sectional flow area of starting end part 443 is arranged to the area less than major component 448, and is arranged to increase gradually along rotor sense of rotation RD1, thereby forms the throttling part.

In the positive z side surface 410 of first plate 41, do not have groove to be formed at the terminal point B of suction side curve bath 430 and discharge between the beginning end points C of side curve bath 440.This zone is called the first closed area RE3, and this first closed area RE3 is by the straight line of the terminal point B that connects spin axis O and suction side curve bath 430 and is connected spin axis O and angle 2 β that the straight line of the beginning end points C of discharge side curve bath 440 forms determine.This angle 2 β equal an about pitch.Similarly, in the positive z side surface 410 of first plate 41, do not have groove to be formed to discharge between the beginning terminal A of the terminal point D of side curve bath 440 and suction side curve bath 430.This zone is called the second closed area RE4, and this second closed area RE4 is by the straight line of the terminal point D that connects spin axis O and discharge side curve bath 440 and be connected spin axis O and angle 2 β that the straight line of the beginning terminal A of suction side curve bath 430 forms determine.This angle 2 β equal an about pitch.When pump chamber r was arranged in the first closed area RE3 or the second closed area RE4, the working fluid among the pump chamber r was closed, so that prevent that fluid is communicated with between suction side curve bath 430 and discharge side curve bath 440.The first closed area RE3 and the second closed area RE4 cross the x axis separately and extend.

First plate 41 is formed with suction side back pressure mouth 45 and discharges side back pressure mouth 46, and they provide independently of one another, and is arranged to and the root of each blade 7 (being formed at the back pressure chamber br in the proximal part 610 of slit 61) hydraulic communication.Suction side back pressure mouth 45 be arranged such that suction port 43 with suck regional RE1 in most of blade 7 corresponding back pressure chamber br hydraulic pressure is connected, particularly with the blade 7 corresponding back pressure chamber brs (suction side curve bath 430) of distal portions 70 with suction port 43 overlappings.Suction side back pressure mouth 45 comprises suction side back pressure curve bath 450 and intercommunicating pore 451.Suction side back pressure curve bath 450 is formed in the positive z side surface 410 of first plate 41, and is arranged to receive the suction side hydrodynamic pressure.When the z axial direction is seen, suction side back pressure curve bath 450 is the form around the circular arc of spin axis O, extends through the part of arranging the back pressure chamber br (proximal part 610 of rotor 6) that is used for blade 7 along the circumferential direction of first plate 41.Suction side back pressure curve bath 450 extends on the angular range of about 3 pitches, and it is less than the angular range of suction side curve bath 430.Suction side back pressure curve bath 450 has beginning end points " a ", and this begins end points " a " and is positioned at the front a little of the beginning terminal A of groove 434 or suction side curve bath 430 along rotor sense of rotation RD1, and is close to major component starting end part 433.Suction side back pressure curve bath 450 has terminal point " b ", and this terminal point " b " is positioned at about 1.5 pitch places, terminal point B back of suction side curve bath 430 along rotor sense of rotation RD1.Suction side back pressure curve bath 450 along even substantially on the whole length of circumferential direction, and equals the size of suction side curve bath 430 along the size of rotor radial direction substantially, and equals the size of the proximal part 610 of slit 61 substantially.Suction side back pressure curve bath 450 has inboard radial edges 454, and this inboard radial edges 454 is positioned at inboard radial edges inboard a little of the proximal part 610 of slit 61 along the rotor radial direction.Suction side back pressure curve bath 450 has outer radial edge 455, and this outer radial edge 455 is positioned at outer radial edge inboard a little of the proximal part 610 of slit 61 along the rotor radial direction.When the z axial direction is seen, no matter where cam ring 8 is positioned at, and suction side back pressure curve bath 450 all overlaps with most of back pressure chamber br (proximal part 610 of slit 61), so as with they hydraulic communication.Intercommunicating pore 451 is positioned at the rotor counterrotating direction side of suction side back pressure mouth 45, and compares more close beginning end points a to terminal point b, and overlaps along the intercommunicating pore 432 of circumferential direction and suction side curve bath 430.When the z axial direction is seen, intercommunicating pore 451 has basic elliptical shape, and equals the width of suction side back pressure curve bath 450 substantially along the width of rotor radial direction, equals an about pitch along the length of circumferential direction.Intercommunicating pore 451 extends through first plate 41 along the z axial direction, and by first communication passage 491 and with intercommunicating pore 432 hydraulic communication of suction side curve bath 430.In suction side back pressure curve bath 450, starting end part 452 is formed between beginning end points a and the inlet hole 431.When the z axial direction is seen, starting end part 452 has semi-circular ends, and this semi-circular ends is protruded along rotor counterrotating direction.Suction side back pressure curve bath 450 has the semicircle end portion of protruding along rotor sense of rotation RD1 453.Starting end part 452 equal along the degree of depth of z axial direction first plate 41 thickness about 40% or littler, and end portion 453 equal along the degree of depth of z axial direction first plate 41 thickness about 20% or littler.Part between part 453 and the intercommunicating pore 451 tilts endways, and like this, the degree of depth increases gradually towards intercommunicating pore 451, and becomes at intercommunicating pore 451 places and to equal the thickness of first plate 41.

Discharge side back pressure mouth 46 and be arranged such that exhaust port 44 is connected with such back pressure chamber br hydraulic pressure, described back pressure chamber br and the major component that is arranged in discharging area RE2, the first closed area RE3, the second closed area RE4 and to suck the blade 7 of a part of regional RE1 corresponding, specifically, these back pressure chamber br is corresponding with the blade 7 of the major component overlapping of a part, the first closed area RE3 or the second closed area RE4 of exhaust port 44, suction side back pressure mouth 45 with distal portions 70.Discharge side back pressure mouth 46 and comprise discharge side back pressure curve bath 460 and intercommunicating pore 461.Discharge side back pressure curve bath 460 and be formed in the positive z side surface 410 of first plate 41, and be arranged to receive discharge side liquid pressure.When the z axial direction is seen, discharge side back pressure curve bath 460 and be form around the circular arc of spin axis O, extend through the part that layout is used for the back pressure chamber br (proximal part 610 of rotor 6) of blade 7 along the circumferential direction of first plate 41.Discharge side back pressure curve bath 460 and extend on the angular range of about 7 pitches, it is greater than the angular range of discharging side curve bath 440.Discharge side back pressure curve bath 460 and extend through the first closed area RE3, and stretch among the regional RE1 of suction, it has beginning end points " c ", this begins end points " c " and is positioned at the back of the beginning end points C that discharges side curve bath 440 along rotor sense of rotation RD1, and is positioned at the back of the end portion B of suction side curve bath 430.The beginning end points c that discharges side back pressure curve bath 460 is positioned at about pitch place, terminal point B back (equaling 2 β angles) of suction side curve bath 430 along rotor sense of rotation RD1.The terminal point " d " of discharging side back pressure curve bath 460 is positioned at an about pitch or the less part of the terminal point D front of discharging side curve bath 440, therefore is positioned closer to the terminal point of the second closed area RE4 along rotor sense of rotation RD1.Discharge side back pressure curve bath 460 along the size of rotor radial direction along even substantially on the whole length of circumferential direction, and be slightly less than the size of discharging side curve bath 440, and be slightly less than the size of the proximal part 610 of slit 61.Discharging side back pressure curve bath 460 has inboard radial edges 464, and this inboard radial edges 464 is positioned at the outside a little of the inside edge of proximal part 610 along the rotor radial direction.Discharging side back pressure curve bath 460 has outer radial edge 465, and this outer radial edge 465 is positioned at the inboard a little of the outer ledge of proximal part 610 along the rotor radial direction.When the z axial direction is seen, no matter where cam ring 8 is positioned at, discharge side back pressure curve bath 460 and all overlap with most of back pressure chamber br (proximal part 610 of slit 61) so that with they hydraulic communication.Intercommunicating pore 461 is positioned to and compares more close beginning end points c to terminal point d, and in the angular orientation between the distolateral x axis (mid point among the first closed area RE3) of the beginning of the terminal point B of suction side curve bath 430 and the first closed area RE3.The diameter of intercommunicating pore 461 equals to discharge side back pressure curve bath 460 width along the rotor radial direction substantially.Intercommunicating pore 461 forms and extends through first plate 41, and with respect to the z axis tilt, thereby makes that the cross section of intercommunicating pore 461 will outwards move along the rotor radial direction when negative z axial direction advances when when the z axial direction is seen.Intercommunicating pore 461 is opened in the negative z side surface of first plate 41, and be arranged through second communication passage 492 and with the intercommunicating pore 441 of exhaust port 44 (discharging side curve bath 440) hydraulic communication.

Discharge side back pressure curve bath 460 and comprise starting end part 462 and back pressure mouth major component 468.Fig. 6 is the sectional view of the pumping part 2 of pump 1, comprises the sectional view of first plate 41 along the line VI-VI among Fig. 3.Back pressure mouth major component 468 is the major components of discharging side back pressure curve bath 460, extends to terminal point d from beginning end points " e ".Beginning end points e is positioned at about 0.4 pitch in terminal point B back or the less part of suction port 43 along rotor sense of rotation RD1.Back pressure mouth major component 468 is even substantially along the degree of depth of z axial direction.When the z axial direction is seen, the starting end edge of back pressure mouth major component 468 467 is basic to become the semicircular in shape of protruding along rotor counterrotating direction.The semicircular in shape that the terminal edge 463 basic one-tenth of back pressure mouth major component 468 or discharge side back pressure curve bath 460 protrude along rotor sense of rotation RD1.Starting end part 462 is positioned at the rotor counterrotating direction side of discharging side back pressure curve bath 460 or along the back of rotor sense of rotation RD1 in back pressure mouth major component 468,467 (beginning end points e) extend 0.5 pitch or more to this starting end part 462 towards the edge from beginning end points c in sucking regional RE1 along rotor sense of rotation RD1.Front end terminal point b, starting end part 462 towards suction side back pressure curve bath 450 is basic rectangle, has the straight edge that extends along the rotor radial direction.Fig. 7 is the enlarged view of the part of the pumping part 2 represented by the VII among Fig. 6, has represented the section shape of starting end part 462.The bottom of starting end part 462 (negative z side surface) is flat substantially.When rotor sense of rotation RD1 sees, starting end part 462 has the rectangular cross-section, and it is along rotor sense of rotation RD1 substantially constant.The degree of depth of starting end part 462 (along the length of z axial direction) is even substantially.Starting end part 462 is as the throttling part, and it has the cross-sectional flow area littler than back pressure mouth major component 468.In first embodiment, starting end part 462 is not limited to rectangular shape in the cross section when rotor sense of rotation RD1 sees, but arbitrary shape can be arranged, as long as cross-sectional flow area is even substantially along rotor sense of rotation RD1.For example, starting end part 462 can have such cross section, and it has the part at the suitable protrusion in the center of bottom.The degree of depth of starting end part 462 can be selected arbitrarily with respect to the ratio of the degree of depth of back pressure mouth major component 468.Second plate 42 comprises discharges side back pressure curve bath 460, is similar to first plate 41.The discharge side back pressure curve bath 460 of second plate 42 comprises back pressure mouth major component 468, this back pressure mouth major component 468 is stretched out from beginning end points e, be similar to the back pressure mouth major component 468 of first plate 41, but do not comprise starting end part 462, different with first plate 41.Promptly second plate 42, form towards the part of the negative z side surface of the starting end part 462 of first plate 41 and not have recess.This feature is used to improve the throttling function of the starting end part 462 of first plate 41, as described later in detail.But, second plate 42 can provide the starting end part 462 in discharging side back pressure curve bath 460, is similar to first plate 41.

As shown in Figure 6, be arranged to enough for a short time along the gap of z axial direction between rotor 6 and first or second plate 41 or 42, flow into discharge the position (the first closed area RE3 etc.) that side back pressure curve bath 460 does not extend to so that prevent working fluid.On the other hand, in the position of discharging side back pressure curve bath 460 was provided, working fluid flows through between rotor 6 and first or second plate 41 or 42 discharged side back pressure curve bath 460.It is porose 466 that intercommunicating pore 461 provides, and this hole 466 is in leading to the passage (discharging side back pressure curve bath 460) of discharging side back pressure mouth 46.Hole 466 is used for the restraint of labour fluid and leads to the flow channel of exhaust port 44 from discharging side back pressure mouth 46, so makes the internal pressure of discharging side back pressure mouth 46 keep higher, impels blade 7 to protrude and improve the starting capability of pump 1.

With reference to figure 2, control section 3 is installed in the housing 4 again, and this control section 3 comprises control valve 30, first and

second fluid passages

31 and 32 and first and second control chamber R1 and the R2.Control valve 30 is a hydraulic control valve, guiding valve for example, and it comprises: spool 302, this spool 302 are installed in the receiving bore 401 that is formed in the enclosure body 40; And solenoid 301, this solenoid 301 is installed in the housing 4, is used to drive spool 302, so that the supply of conversion work fluid between the first fluid passage 31 in being formed at enclosure body 40 and second fluid passage 32.The first fluid passage 31 and first communication passage 931 constitute the first control fluid passage.Second fluid passage 32 and second communication passage 932 constitute the second control fluid passage.The operation of control valve 30 is controlled according to parameter (for example engine speed and throttle valve opening) by CVT control unit 300.

Pump function

When rotor 6 is positioned to respect to spin axis O when rotating under the situation of positive x axial direction off-centre at cam ring 8, each pump chamber r periodically expands and shrinks, and rotates around spin axis O simultaneously.Working fluid sucks each pump chamber r in the regional RE1 of the suction of negative y side by suction port 43, suck among the regional RE1 at this, pump chamber r expands when moving together along with the rotation of rotor 6, and working fluid is discharged from each the pump chamber r among the discharging area RE2 of negative y side by exhaust port 44, in this discharging area RE2, pump chamber r shrinks when moving together along with the rotation of rotor 6.Specifically, in sucking regional RE1, each pump chamber r expands continuously, up to rotor counterrotating direction lateral lobe sheet 7 (the rear side blades 7) of pump chamber r terminal point B through suction side curve bath 430, promptly up to the rotor sense of rotation lateral lobe sheet 7 (front side blade 7) of pump chamber r through discharging the beginning end points C of side curve bath 440.In this time course, pump chamber r keeps being connected with suction side curve bath 430 hydraulic pressure, thereby sucks working fluid by suction port 43.When each pump chamber r is arranged in the first closed area RE3, the rotor sense of rotation side surface of promptly working as the rear side blade 7 of pump chamber r is positioned at the terminal point B place of suction side curve bath 430, and when the rotor counterrotating direction side surface of the front side blade 7 of pump chamber r is positioned at the beginning end points C place that discharges side curve bath 440, pump chamber r separates with discharge side curve bath 440 hydraulic pressure with suction side curve bath 430, so the sealing of liquid seal ground.At the rotor sense of rotation side surface of the rear side blade 7 of pump chamber r terminal point B through suction side curve bath 430, and when the rotor counterrotating direction side surface of the front side blade 7 of pump chamber r process is discharged the beginning end points C of side curve bath 440, pump chamber r shrinks when moving along with the rotation of rotor 6, and with discharge side curve bath 440 hydraulic pressure and be connected so that by exhaust port 44 discharge working fluids.Similarly, when each pump chamber r is arranged in the second closed area RE4, the rotor sense of rotation side surface of promptly working as the rear side blade 7 of pump chamber r is positioned at the terminal point D place that discharges side curve bath 440, and when the rotor counterrotating direction side surface of the front side blade 7 of pump chamber r is positioned at the beginning terminal A place of suction side curve bath 430, pump chamber r separates with discharge side curve bath 440 hydraulic pressure with suction side curve bath 430, so the sealing of liquid seal ground.In first embodiment, the first closed area RE3 and the second closed area RE4 each have the scope (being the width of pump chamber r along circumferential direction) of a pitch.This is used to prevent improve pump efficiency simultaneously sucking fluid connection between regional RE1 and the discharging area RE2.But, the first closed area RE3 and the second closed area RE4 (spacing between suction port 43 and exhaust port 44) are not restricted to a pitch separately, but the angular range greater than a pitch can be arranged.That is, the scope separately of the first closed area RE3 and the second closed area RE4 can be provided with arbitrarily, is sucking fluid connection between regional RE1 and the discharging area RE2 as long as can prevent.When the rotor counterrotating direction side surface of the front side of pump chamber r blade 7 when the first closed area RE3 moves to discharging area RE2, the throttling function of discharging the starting end part 443 of side curve bath 440 is used to prevent that rapid fluid is communicated with between pump chamber r and discharge side curve bath 440, thereby suppresses the pressure fluctuating in inner of exhaust port 44 and pump chamber r.This prevents working fluid, and exhaust port 44 flow directions of high pressure have the more pump chamber r of low-pressure by having more fast, thereby the flow velocity that prevents working fluid supply outside pipeline (this outside pipeline is connected with exhaust port 44 by tap hole 442) reduces fast.This has suppressed ducted fluid impact (being ducted hydrodynamic pressure fluctuation).Increase fast because prevent to supply with the flow velocity of the working fluid of pump chamber r like this, therefore prevent the pressure fluctuating in inner of pump chamber r.But, the starting end part 443 of discharging side curve bath 440 can be omitted or variation arbitrarily.On the other hand, when the rotor counterrotating direction side surface of the front side of pump chamber r blade 7 moves to when sucking regional RE1 from the second closed area RE4, the throttling function of the groove 434 of suction port 43 is used to prevent that rapid fluid is communicated with between pump chamber r and suction side curve bath 430, and therefore suppresses the pressure fluctuating in inner of suction port 43 and pump chamber r.This prevents working fluid, and the fast flow speed and direction of pump chamber r of high pressure has the more suction port 43 of low-pressure from having more, and therefore prevents to produce bubble (hole).But, groove 434 can omit or change arbitrarily.

Variable displacement

When cam ring 8 is positioned to along positive x axial direction off-centre with respect to spin axis O, thereby make the eccentricity delta greater than zero the time, pump chamber r expands when negative y side is moved together along with the rotation of rotor 6.When pump chamber r is arranged in the positive x side of the first closed area RE3 at the x axis, the cubical content maximum of pump chamber r.On the other hand, pump chamber r shrinks when positive y side is moved together along with the rotation of rotor 6.When pump chamber r is arranged in the negative x side of the second closed area RE4 at the x axis, the cubical content minimum of pump chamber r.When cam ring 8 is positioned at the maximum eccentric position, as shown in Figure 2, the cubical content difference maximum between the contraction pump chamber r of minimum and maximum expansion pump chamber r, so pump capacity maximum.On the other hand, when cam ring 8 moved to minimum eccentric position along negative x axial direction, the eccentricity delta became zero, and pump chamber r does not expand, do not shrink when moving together along with the rotation of rotor 6 on positive y side and any position of negative y side.Like this, the cubical content difference between the contraction pump chamber r of minimum and maximum expansion pump chamber r is decreased to zero, and therefore, pump capacity is decreased to zero.Like this, when the eccentricity of cam ring 8 changed, the cubical content difference changed, so pump capacity changes.

When not having working fluid to supply with the first control chamber R1 and the second control chamber R2, cam ring 8 is positioned under the partial pressure of spring 12 along positive x axial direction off-centre, like this, and eccentricity delta's maximum.The first control chamber R1 supplies with working fluid by the first control fluid passage by control valve 30.The hydrodynamic pressure of supplying with is used to produce first hydraulic coupling, so that push cam ring 8 against the biasing force of spring 12 along negative x axial direction.On the other hand, the second control chamber R2 supplies with working fluid by the second control fluid passage by control valve 30.The hydrodynamic pressure of supplying with is used to produce second hydraulic coupling, so that the biasing force of additional springs 12 is pushed cam ring 8 along positive x axial direction.The operation of CVT control unit 300 control control valves 30, and therefore change first and second hydraulic couplings by making working fluid supply to the first and second control chamber R1 and R2 suitably and discharging from the first and second control chamber R1 and R2.This operation makes cam ring 8 move, thereby the eccentricity delta is changed.Like this, CVT control unit 300 control pump capacity.More particularly, when the hydraulic pressure among the first control chamber R1 increased, first hydraulic coupling increased.On the other hand, when the hydraulic pressure among the second control chamber R2 increased, second hydraulic coupling increased.When making a concerted effort along negative x axial direction of first and second hydraulic couplings, and when making a concerted effort biasing force (this biasing force is pushed cam ring 8 along positive x axial direction) greater than spring 12, cam ring 8 moves along negative x axial direction.This causes the eccentricity delta to reduce, and the cubical content difference between contraction state and swelling state reduces, thereby causes pump capacity to reduce.The second control chamber R2 can omit, and like this, has only the first control chamber R1 to be used to make cam ring 8 motions.The device that is used for constant bias cam ring 8 is not limited to wind spring, but can implement by different way.When internal-combustion engine was operated in predetermined high-speed region, the volume controlled of pump 1 was for very little but very abundant, so that the required moment of torsion of reduction driven pump 1.Compare with fixed displacement pump, this feature is favourable.

By providing different types of back pressure mouth to reduce power loss

When rotor 6 rotations, blade 7 is subjected to along the centrifugal force of the outside effect of rotor radial direction.Therefore, when satisfying predetermined condition (this condition comprises that the rotating speed of needs rotor 6 is enough high), the distal portions 70 of blade 7 protrudes from slit 61, so that the interior perimeter surface 80 of contact cam ring 8.This contact has limited blade 7 outwards moving along the rotor radial direction.When blade 7 moved outside slit 61, the back pressure chamber br in blade 7 back expanded.On the other hand, when blade 7 moved in slit 61, the back pressure chamber br in blade 7 back shrank.When rotor 6 is positioned to when rotating under the positive state of x axial direction with respect to spin axis O off-centre at cam ring 8, the back pressure chamber br that is used for each blade 7 of contacting with the interior perimeter surface 80 of cam ring 8 periodically expands along with the rotation of rotor 6 and shrinks.The negative y side that expands at back pressure chamber br, so that blade 7 can protrude the time, the distal portions 70 of blade 7 can contact with the interior perimeter surface 80 of cam ring 8, so does not form the liquid seal of pump chamber r when the working fluid of not supplying with q.s.On the other hand, positive y side in back pressure chamber br contraction, when working fluid is not successfully discharged so that blade 7 can inwardly move or be retracted in the slit 61 time from back pressure chamber br, the distal portions 70 of blade 7 may be subjected to high surface friction drag during the interior perimeter surface 80 of cam ring 8 contacts.In pump 1, in negative y side, back pressure chamber br supplies with working fluid by suction side back pressure mouth 45.This is used to improve the outside motion of blade 7.

In positive y side, working fluid is discharged to discharging side back pressure mouth 46 from back pressure chamber br.This is used to reduce the resistance of the slip that hinders blade 7.In negative y side, the distal portions 70 of blade 7 is subjected to the pressure from suction port 43, and the proximal part 71 of blade 7 is subjected to the pressure from suction side back pressure mouth 45.Because suction side back pressure mouth 45 is connected with suction port 43 hydraulic pressure by first communication passage 491, so the internal pressure of suction port 43 equals the internal pressure of suction side back pressure mouth 45 substantially.Therefore, the distal portions 70 that prevents blade 7 does not need ground powerful by (comparing with situation about being used for as back pressure chamber br when exhaust port receives high hydraulic pressure) on the interior perimeter surface 80 that is pressed in cam ring 8.This causes loss of machine of torque to reduce (loss of machine of torque is because the friction between the interior perimeter surface 80 of the distal portions 70 of blade 7 and cam ring 8).In other words, this feature is used to reduce the surface friction drag that the distal portions 70 of blade 7 slides on the interior perimeter surface 80 of cam ring 8, and therefore reduces power loss (with comparing when the proximal part 71 that be arranged in all blades 7 that suck regional RE1 all is applied in the situation of discharging side pressure).

On the other hand, in positive y side, the distal portions 70 of blade 7 is subjected to the pressure from exhaust port 44, and the proximal part 71 of blade 7 is subjected to from the pressure of discharging side back pressure mouth 46.Because discharge side back pressure mouth 46 by second communication passage 492 and be connected with exhaust port 44 hydraulic pressure, so the distal portions 70 of blade 7 and proximal part 71 are subjected to essentially identical pressure.Therefore, the distal portions 70 that prevents blade 7 is not needed ground powerful by on the interior perimeter surface 80 that is pressed in cam ring 8.This is used to reduce the moment of torsion that loses owing to the friction between the interior perimeter surface 80 of the distal portions 70 of blade 7 and cam ring 8.

Generally speaking, in pump 1, suction side back pressure mouth 45 and discharge side back pressure mouth 46 are respectively applied for back pressure chamber br, and therefore, in sucking regional RE1 and among the discharging area RE2, the distal portions 70 and the proximal part 71 of blade 7 all are subjected to basic identical pressure.It is suitable for being pressed in cam ring 8 that this feature is used to make that blade 7 comes by centrifugal force, is reduced in the surface friction drag between blade 7 and the cam ring 8 simultaneously.This is used to reduce the wearing and tearing between the interior perimeter surface 80 of blade 7 and cam ring 8, and reduces power loss, because the required driving torque of rotor 6 rotations is reduced.Like this, pump 1 forms efficient low moment of torsion type of pump, wherein, compare with common variable delivery pump, required driving torque relative rotation speed is littler, and fuel efficiency improves by reducing power loss, even and when outside dimensions is identical rate of discharge also bigger (pump 1 can form compactly).

Push by blade and to prevent that through-flow from crossing blade

As mentioned above, in sucking regional RE1, blade 7 is mainly realized by centrifugal force from the interior perimeter surface 80 that slit 61 is protruding to cam ring 8.Therefore, when internal-combustion engine when low-speed region is operated, for example when engine start or during idling, rotor 6 slowly rotates, and like this, centrifugal force is less, and the distal portions 70 of blade 7 may not contact with the interior perimeter surface 80 of cam ring 8, because it is insufficient to be used for the pressing force of distal portions 70.This protrusion amount that is based on blade 7 depends on along the rotor radial direction and outwards acts on power on the blade 7.This advocates to depend on the viscosity and the friction between blade 7 and slit 61 of centrifugal force, working fluid.Wherein, action of centrifugal force maximum.When each pump chamber r was arranged in the first closed area RE3 or the second closed area RE4, pump chamber r changed between regional RE1 of suction and discharging area RE2 along with the rotation of rotor 6.When blade 7 not with situation that the interior perimeter surface 80 of cam ring 8 contacts under (because the protrusion of blade 7 is insufficient) when entering among the first closed area RE3 or the second closed area RE4, pump 1 may run into following problem.

When the rear side blade 7 of the first pump chamber r is arranged in the first closed area RE3, the front side blade 7 of the first pump chamber r is arranged in discharging area RE2, like this, the first pump chamber r is connected with exhaust port 44 hydraulic pressure, therefore the internal pressure of the first pump chamber r is higher, because the first closed area RE3 equals a pitch along the length of circumferential direction.At this moment, adjacent with the first pump chamber r and be arranged at the rear side blade 7 of the second pump chamber r of the first pump chamber r back along rotor sense of rotation RD1 and suck regional RE1, like this, the second pump chamber r is connected with suction port 43 hydraulic pressure, and therefore the internal pressure of the second pump chamber r is relatively low.When the internal pressure of the therefore first pump chamber r obvious different with the second pump chamber r (this second pump chamber r is adjacent with the first pump chamber r), and with the protrusion of the separated blade 7 of the first and second pump chamber r and when insufficient, working fluid may be revealed or flows to low voltage side pump chamber r from high pressure side pump chamber r by the gap between the interior perimeter surface 80 of the distal portions 70 of blade 7 and cam ring 8.This phenomenon is called blade and connects stream.This possibility is higher relatively when pump 1 is operated at low temperatures.The leakage of working fluid or blade connect stream and may cause working fluid to flow fast and the pressure surge in exhaust port 44 and suction port 43, thereby cause noise.Like this, the pressure in exhaust port 44 periodically reduces along with rotor 6 rotations the time, thereby causes the head pressure pulsation.This amount of working fluid of make discharging reduces, and discharges side pressure and reduce, thereby makes pump efficiency reduce, utilize this pump discharge head system (CVT 100) but startability reduce.

Consider the problems referred to above, pump 1 is arranged so that the back pressure chamber br that is used for each blade 7 had been applied in high pressure before blade 7 enters the first closed area RE3.This guarantees that blade 7 is outwards pushed along the rotor radial direction, and contacts with the interior perimeter surface 80 of cam ring 8, and like this, blade 7 liquid seal ground separates two adjacent pump chamber r and sealing each other.Fig. 8 is the sectional view of pump 1 along the line VIII-VIII among Fig. 6.In Fig. 8, the interior week of the periphery of rotor 6, the cam ring 8 and shape of suction side curve bath 430 etc. is schematically illustrated by straight line, and omits the projection 62 of rotor 6.As shown in Figure 8, discharge side back pressure mouth 46 (discharging side back pressure curve bath 460) and also stretch among the regional RE1 of suction, the beginning end points c that discharges side back pressure mouth 46 locates along the terminal point B back certain distance L 0 (pitch) that rotor sense of rotation RD1 is positioned at suction port 43 (suction side curve bath 430).Distance L 0 can be more greater or lesser than a pitch.According to this structure, before blade 7 enters the first closed area RE3, promptly when blade 7 when rotor sense of rotation RD1 is positioned at the terminal point B back of suction port 43, the back pressure chamber br that is used for blade 7 with discharge side back pressure mouth 46 hydraulic pressure and be connected.When the back pressure chamber br of the blade 7 that is used for not contacting with the interior perimeter surface 80 of cam ring 8 enters the discharge side back pressure mouth 46 of end portion 436 of suction port 43, discharging side pressure supplies with and is applied on the proximal part 71 of blade 7 from discharging side back pressure mouth 46, like this, blade 7 outwards moves into and cam ring 8 face contacts along the rotor radial direction.When the terminal point B that surpasses suction port 43 along with the rotation of rotor 6 when blade 7 entered the first closed area RE3, blade 7 had been pressed into cam ring 8 and contact, thereby prevents fluid connection between suction port 43 and exhaust port 44.Like this, when pump chamber r from sucking regional RE1 when discharging area RE2 moves, each pump chamber r keeps liquid seal.After blade 7 entered the first closed area RE3, the back pressure chamber br that is used for blade 7 was connected with discharge side back pressure mouth 46 hydraulic pressure, thereby is subjected to high pressure, and like this, blade 7 keeps and cam ring 8 face contacts.Like this, the back pressure chamber br that is used for blade 7 (this blade 7 is determined at the pump chamber r that sucks the first closed area RE3 between regional RE1 and the discharging area RE2) will be applied with high pressure, like this, the distal portions 70 of blade 7 is by in the distal portions 70 of blade 7 and the pressure difference between the proximal part 71 and on by the interior perimeter surface 80 that is pressed in cam ring 8.This is used to keep being located immediately at along rotor sense of rotation RD1 the liquid seal of the pump chamber r of discharging area RE2 back, and provides sealing between low pressure suction side and high pressure discharge side.This feature is used to make blade 7 to move outside slit 61, thereby making pump 1 normally to carry out sucks and discharge function, even when the viscosity of working fluid is higher, for example in the cold starting process (so blade 7, insufficient) based on the pressing force of centrifugal force.But therefore improved pump 1 startability at low temperatures.

Reduce loss of machine of torque by the scope setting of discharging side back pressure mouth

Before entering the first closed area RE3, the back pressure chamber br that is used for blade 7 is applied with the angular range of high pressure when too wide, because the loss of machine of torque that friction causes increases, the effect that reduces power loss reduces, because blade 7 is also very wide with the angular range of the interior perimeter surface 80 face contacts ground slip of cam ring 8.Because optional equipment, the size of common variable delivery pump is usually greater than the size of the ordinary fixed displacement pump with same capability.Therefore, in the constant low-speed region of pump capacity (or fixed capacity zone), the efficient of common variable delivery pump is lower than common fixed displacement pump, and promptly when rotating speed is identical, the required driving torque of variable delivery pump is greater than the required driving torque of fixed displacement pump.Although the efficient of pump 1 improves as mentioned above, the inadequate zone of effect that exists efficient to be lower than fixed displacement pump and to reduce power loss.Therefore, wish further to reduce the power loss of variable delivery pump.Therefore, pump 1 is arranged to like this, and the shape (cross-sectional flow area and the position of beginning end points c) of discharging side back pressure mouth 46 is adjusted to and optimizes the back pressure chamber that is used for blade 7 provided high pressure before entering the first closed area RE3 angular range.This is used to prevent that through-flow from crossing the blade 7 between pump chamber r, even and also reduce power loss in low-speed region (efficient is relatively low in this low-speed region).

When the rotor sense of rotation side surface of first blade 7 (this first blade 7 is less relatively from the protrusion of slit 61) during, adjacent with first blade 7 and pass through the beginning end points C of exhaust port 44 at the rotor counterrotating direction side surface of second blade 7 of its front along rotor sense of rotation RD1 through the terminal point B of suction port 43.Therefore, when the distal portions 70 of first blade 7 does not contact with the interior perimeter surface 80 of cam ring 8, arrive at the rotor sense of rotation side surface of first blade 7 before the terminal point B of suction port 43, will and the working fluid of the corresponding amount of distance between blade 7 and cam ring 8 to supply with the back pressure chamber br that is used for first blade 7 just enough by discharging side back pressure mouth 46.When such supply working fluid, before the rotor sense of rotation side surface of first blade 7 arrives the terminal point B of suction port 43, finish making blade 7 be pressed into to contact with the interior perimeter surface 80 of cam ring 8.This be used to guarantee pump chamber r begin with discharge 44 hydraulic communication before this pump chamber r liquid seal of determining by first and second blades 7.

Preferably, when the rotor sense of rotation side surface of first blade 7 arrives the position of terminal point B of as close as possible suction port 43, finish and the supply of the working fluid of the corresponding amount in gap between first blade 7 and cam ring 8.This be because, the distal portions 70 that preferably reduces blade 7 is along the scope of rotor sense of rotation RD1 in interior perimeter surface 80 face contacts of the terminal point B back of suction port 43 and cam ring 8, and therefore reducing loss of machine of torque (considers such fact, promptly before the supply of finishing the working fluid that makes the blade 7 of winning contact aequum with cam ring 8, first blade 7 does not contact with cam ring 8).Therefore, in pump 1, discharge the shape of side back pressure mouth 46 and be arranged to like this, make and when the rotor sense of rotation side surface of first blade 7 arrives the position of terminal point B of as close as possible suction port 43, just finish with the supply of the working fluid of this corresponding amount in gap.

Specifically, equation below keeping, wherein, " A " expression is from the cross-sectional flow area of the fluid passage of discharge side back pressure mouth 46 to the back pressure chamber br that is used for blade 7, promptly when the cross-sectional flow area of discharging side back pressure mouth 46 when rotor sense of rotation RD1 sees; Q represents the amount (volume flow rate) of the working fluid of time per unit from discharge side back pressure mouth 46 inflow back pressure chamber br; " C " represents efflux coefficient; ρ represents the density of working fluid; And Δ P represents the pressure difference (in the pressure difference of discharging between side back pressure mouth 46 and the back pressure chamber br (≈ head pressure)) by the fluid passage:

Q＝C·A·√(2·ΔP/ρ)

Be used for as supply blade 7 back pressure chamber br working fluid total amount amount ∫ Q (time integral of Q) with when the back pressure chamber br that is used for blade 7 with discharge side back pressure mouth 46 hydraulic pressure when being connected time T and the product of cross-sectional flow area A be directly proportional.Time T depends on that the rotating speed (or gait of march of blade 7) of rotor 6 and blade 7 are along the range ability L of rotor sense of rotation RD1 in discharging side back pressure mouth 46 ^*(being the angular range that back pressure chamber br advances from the beginning end points c that discharges side back pressure mouth 46).When the rotating speed of rotor 6 is assumed to be when constant, time T is by travel distance L ^*Determine.Generally speaking, amount ∫ Q is by the cross-sectional flow area A and the travel distance L that discharge side back pressure mouth 46 ^*(perhaps beginning the position of end points c) determined.

In pump 1, distance (angular range) L from the beginning end points c of starting end part 462 to the beginning end points e of back pressure mouth major component 468 and the cross-sectional flow area A that discharges the starting end part 462 of side back pressure mouth 46 are arranged so that Fluid Volume ∫ Q is with consistent corresponding to the amount of working fluid in the gap between blade 7 and the cam ring 8.In other words, distance L and cross-sectional flow area A are arranged to like this, when blade 7 when the beginning end points c of starting end part 462 moves to the beginning end points e of back pressure mouth major component 468, Fluid Volume ∫ Q equals to supply with back pressure chamber br so that the total amount that the distal portions 70 of blade 7 is contacted with the interior perimeter surface 80 of cam ring 8.Like this, discharge side back pressure mouth 46 and be arranged such that blade 7 contacts with the interior perimeter surface 80 of cam ring 8 at the beginning end points e place near terminal point B, cross the blade 7 between pump chamber r so that prevent through-flow, and suppress the loss of machine of torque that causes owing to useless face contact.

Fig. 9 can reduce loss of machine of torque having represented to discharge the cross-sectional flow area A of starting end part 462 of side back pressure mouth 46 and the combination of distance L by part down by this combination, prevents the blade through-flow simultaneously, so makes power loss in the permission zone.This relation can be determined according to test, perhaps estimate according to design load.Pump 1 is arranged so that the point of being determined by cross-sectional flow area A and distance L is arranged in the zone of being represented by the shadow pattern of Fig. 9.Allow the zone can be defined as like this, when in the predetermined low-speed region that is comprising the fixed displacement zone or when in the frequent pattern of using low-speed region, the loss of machine of torque of total torque loss and ordinary fixed displacement pump quite or littler.Therefore, though when the CVT that adopts pump 1 when operating under the frequent pattern of using low-speed region (efficient is relatively low in this low-speed region), the power loss of pump 1 also be decreased to the power loss of ordinary fixed displacement pump quite or lower level.Also have, even (this power steering system uses low-speed region always as power steering system when pump 1, efficient is relatively low in this low-speed region) the hydrodynamic pressure supply source time, the power loss of pump 1 can be decreased to the power loss of ordinary fixed displacement pump quite or lower.

Cross-sectional flow area A and distance L are arranged in such appropriate area (to be represented by the shadow pattern among Fig. 9), even when blade 7 under the influence of rotating speed, fluid temperature (F.T.) etc. when contact with cam ring 8, because the loss of machine of torque (blade loss of machine of torque) that the face contact of blade 7 causes also is lower than the regional upper limit of permission along some place beginning of rotor sense of rotation RD1 in the beginning end points e back of back pressure mouth major component 468.When blade 7 is sucking when keeping among the regional RE1 contact with cam ring 8, blade 7 is continuation and cam ring 8 face contacts after through the beginning end points c of starting end part 462, and therefore, loss of machine of torque becomes and equals the upper limit of appropriate area.The maximum permissible value value of being arranged to Lmax of distance L, it is on the border of the allowed band of blade loss of machine of torque, as shown in Figure 9.

On the other hand, when blade 7 under the influence of rotating speed, fluid temperature (F.T.) etc. when contacting with cam ring 8 along some place beginning of rotor sense of rotation RD1 in the beginning end points e front of back pressure mouth major component 468, back pressure chamber br after blade 7 is through beginning end points e to be supplied to working fluid, because the cross-sectional flow area of back pressure mouth major component 468 is arranged to the cross-sectional flow area greater than the starting end part 462 in the discharge side back pressure mouth 46 than bigger before flow velocity.This feature is used for guaranteeing to prevent that blade from connecting stream, because before the rotor sense of rotation side surface of blade 7 arrives the terminal point B of suction port 43 again through the beginning end points e of back pressure mouth major component 468, finished and the supply of the working fluid of the corresponding amount in gap between blade 7 and cam ring 8.Pump 1 can change, and like this, when the rotor sense of rotation side surface of blade 7 arrived the terminal point B of suction port 43, the supply of the working fluid of aequum was finished.For example, the beginning end points e of back pressure mouth major component 468 can move into identical with the terminal point B of suction port 43, and like this, starting end part 462 extends to terminal point B from beginning end points c.In this case, the scope of blade 7 sliding contacts further reduces, so that more effectively reduce loss of machine of torque.For this situation, the correct position (the perhaps OK range of distance L) of beginning end points c can be determined with reference to the position of the terminal point B of suction port 43.

Partly reduce noise by throttling

Even aforesaid, discharge side back pressure mouth 46 and form and reduce loss of machine of torque and prevent that simultaneously blade from connecting in the structure of stream, may produce noise when cross-sectional flow area A is big.When pressurized working fluid with under the situation that cam ring 8 contacts does not begin to flow through the big cross-sectional flow area A during to back pressure chamber br that discharges side back pressure mouth 46 at blade 7, working fluid can flow among the back pressure chamber br fast, like this, blade 7 is towards cam ring 8 motions with than hard place collision cam ring 8, thus the generation noise.

Foregoing problems solves by pump 1, wherein, discharges side back pressure mouth 46 and provides starting end part 462, and this starting end part 462 has the cross-sectional flow area A that reduces, and therefore forms the throttling part.When the back pressure chamber br that is used for blade 7 (proximal part 610 of slit 61) was positioned at starting end part 462 (the beginning end points e from beginning end points c to back pressure mouth major component 468), working fluid flow through starting end part 462 to back pressure chamber br from back pressure mouth major component 468.Because the cross-sectional flow area of starting end part 462 is arranged to the cross-sectional flow area less than back pressure mouth major component 468, so the restraint of labour fluid is supplied with the flow velocity (flow velocity Q) of back pressure chamber br.

Specifically, the cross-sectional flow area A of starting end part 462 is adjusted to like this, and when distal portions 70 contacted with the interior perimeter surface 80 of cam ring 8, blade 7 was optimized along the outside gait of march V of rotor radial direction, therefore, since the noise that the contact of blade 7 produces in allowing the zone.For example, speed V is arranged in the noise that allows certain level in the cold starting process, and suppresses the generation of noise when pump 1 is in idle running.Speed V is relevant with the cross-sectional flow area A of starting end part 462, as follows with the cross sectional area S ((pressure receiving area)=(size of rotor sense of rotation RD1) * (along size of z axial direction)) of blade 7:

V=Q/S=CA/S √ (2 Δ P/ ρ), perhaps

H=C/V √ (2 Δ P/ ρ), wherein, H represents that area compares S/A.

Utilize above-mentioned equation, speed V optimizes than H by regulating area.In other words, the cross-sectional flow area A of starting end part 462 regulates with reference to cross sectional area S, so that obtain optimal speed V.Specifically, the cross-sectional flow area A of starting end part 462 is arranged in the scope from predetermined minimum value Amin to predetermined maximum Amax.Maximum value Amax is according to allowing noise level to determine.Minimum value Amin determines according to distance L.

Fig. 9 has represented in the part of top in cross-sectional flow area A that discharges side back pressure mouth 46 and the relation between the noise level.This relation can be found by test, perhaps estimate according to design load.Pump 1 is arranged so that the cross-sectional flow area A of the starting end part 462 of discharging side back pressure mouth 46 is arranged in the OK range of Amin to Amax, so noise level is lower than the upper limit of allowed band.Therefore, the permission of cross-sectional flow area A and distance L combination is arranged in the zone of being represented by the shadow pattern of Fig. 9.Therefore, when the back pressure chamber br of the blade 7 that is not contacting with cam ring 8 in sucking regional RE1 moved into and discharge side back pressure mouth 46 overlappings, the throttling function of starting end part 462 was used for limiting the flow velocity Q of the working fluid that flows into back pressure chamber br.Therefore, the speed V that moves at beginning end points e place when contact with cam ring 8 when blade 7 reduces, and like this, has suppressed the speed of blade 7 when collision cam ring 8, thereby has suppressed the noise owing to the contact generation of blade 7.

According to the restriction effect that produces by starting end part 462, the flow velocity Q of the working fluid of discharging from back pressure mouth major component 468 is restricted, like this, to prevent that the pressure in the back pressure mouth major component 468 from producing fluctuation or pulsation, therefore, be applied to hydraulic coupling on the blade 7 substantially constant that becomes by back pressure chamber br (this back pressure chamber br is connected with back pressure mouth major component 468 hydraulic pressure).Like this, in discharging area RE2, each blade 7 keeps and cam ring 8 stable contacts.

When the z axial direction is seen, starting end part 462 has basic rectangular cross-section, and is wherein, constant along the rotor sense of rotation along the degree of depth of z axial direction.That is, starting end part 462 along the size of rotor radial direction along rotor sense of rotation RD1 substantially constant, and also substantially constant of the degree of depth of starting end part 462.Therefore, the cross-sectional flow area A of starting end part 462 is along rotor sense of rotation RD1 substantially constant, like this, supplies with the flow velocity Q substantially constant of working fluid of the back pressure chamber br of the blade 7 that is positioned at starting end part 462 places.This can be provided with the speed V that moves into the blade 7 that contacts with cam ring 8 at an easy rate.

With comparison example compare operation and effect

Figure 10 is the sectional view of the vane pump of first comparison example, and it is corresponding to the sectional view of Fig. 8.Figure 11 is the sectional view of the vane pump of second comparison example, and it is corresponding to the sectional view of Fig. 8.As shown in Figure 10, in first comparison example, discharging side back pressure mouth 46 (discharging side back pressure curve bath 460) forms also and extends in sucking regional RE1, but discharge the terminal point B of the more close suction port 43 of beginning end points c1 of side back pressure mouth 46, wherein, the distance L 1 between beginning end points c1 and terminal point B equal a value more much smaller than the lower limit Lmin of OK range (L1＜＜Lmin).And the cross-sectional flow area A that discharges side back pressure mouth 46 is identical with first embodiment's back pressure mouth major component 468, and the value of equaling A0, this be worth A0 than the upper limit Amax of OK range much bigger (A0＞＞Amax).

In first comparison example, the amount of working fluid of back pressure chamber br of supplying with the blade 7 enter the first closed area RE3 is insufficient, so the protrusion of blade 7 postpones, thereby allows blade to connect stream.Specifically, outside the appropriate area of combined location in Fig. 9 of cross-sectional flow area A0 and distance L 1, blade therefore may occur and connect stream.Therefore, in first comparison example, move to the time of terminal point B from beginning end points c1 at the rotor sense of rotation side surface of blade 7, the Fluid Volume ∫ Q that supplies with the working fluid of back pressure chamber br be lower than and blade 7 and cam ring 8 between the corresponding amount in gap (being used to eliminate the amount in gap).Therefore, produce blade and connect stream, because when the rotor sense of rotation side surface of blade 7 arrived terminal point B, the distal portions 70 of blade 7 did not contact with the interior perimeter surface 80 of cam ring 8.

And in first comparison example, the gait of march of blade 7 is higher when blade 7 collides with cam ring 8, because cross-sectional flow area A is excessive.Specifically, the cross-sectional flow area A0 of first comparison example is greater than the upper limit Amax in the zone when noise level is in allowed band.Because the discharge side back pressure mouth 46 of first comparison example does not provide such throttling part (according to first embodiment's starting end part 462), so working fluid flows among the back pressure chamber br fast.Therefore, when blade 7 when contacting with the interior perimeter surface 80 of cam ring 8 after the terminal point B, the speed V of blade 7 is higher.Therefore, the noise that causes owing to the contact or the collision of blade 7 is outside allowed band.

As shown in Figure 11, the discharge side back pressure mouth 46 of second comparison example has beginning end points c2, this beginning end points c that begins the end points c2 and first embodiment is basic identical, wherein, distance L 2 between the terminal point B of beginning end points c2 that discharges side back pressure mouth 46 and suction port 43 equals first embodiment's distance L 0 substantially, and less than the CLV ceiling limit value Lmax of OK range (L2 ≈ L0＜Lmax).And the cross-sectional flow area A of the discharge side back pressure mouth 46 in sucking regional RE1 is identical with first embodiment's back pressure mouth major component 468, the value of equaling A0, this be worth A0 than the upper limit Amax of OK range much bigger (A0＞＞Amax).

In second comparison example, the amount of working fluid of supplying with the back pressure chamber br of the blade 7 that enters the first closed area RE3 is enough to prevent that blade from connecting stream.But, blade 7 more Zao time and cam ring 8 sliding contacts in than first embodiment.This is because the cross-sectional flow area A of the discharge side back pressure mouth 46 of second comparison example bigger than first embodiment, therefore, when the rotor sense of rotation side surface of blade 7 from beginning end points c2 march to a F (this F first embodiment, in beginning end points c2 front distance L ^*The back of point) time, the Fluid Volume ∫ Q that supplies with the working fluid of back pressure chamber br surpass and blade 7 and cam ring 8 between the corresponding amount in gap (being used to eliminate the amount in gap).Therefore, when the distal portions 70 of blade 7 before through terminal point B, do not need by the interior perimeter surface 80 that is pressed in cam ring 8 on the time the zone greater than first embodiment, so loss of machine of torque is bigger, but in the OK range of being represented by the shadow pattern among Fig. 9.

On the other hand, in second comparison example, the speed of this blade 7 is higher when blade 7 collision cam rings 8, because the discharge side back pressure mouth 46 of first comparison example does not provide such throttling part (first embodiment's starting end part 462), so cross-sectional flow area A is excessive.Specifically, the cross-sectional flow area A0 of first comparison example is greater than the upper limit Amax in the zone of noise level in allowed band.Therefore, with identical in first comparison example, when blade 7 when contacting with the interior perimeter surface 80 of cam ring 8 after the terminal point B, the speed V of blade 7 is higher.Therefore, the noise that produces owing to the collision of blade 7 is outside allowed band.

On the contrary, in first embodiment, the cross-sectional flow area A and the distance L of the starting end part 462 of the discharge side back pressure mouth 46 in sucking the zone are arranged in the zone of being represented by the shadow pattern among Fig. 9, so as to consider shown in Fig. 9, the relation between these parameters and optimize sealing effect, loss of machine of torque and noise level simultaneously.Therefore, can prevent that blade from connecting stream, suppress pulsation and noise, but and suppress adverse effect pump efficiency and startability.And, can reduce when blade 7 do not need the zone when being pressed on the cam ring 8, thereby reduce power loss.And, can prevent that quick inflow of working fluid is used for the back pressure chamber br of blade 7, thereby further suppress the generation of noise.Particularly when in low-temperature condition (in low-temperature condition, the viscosity of working fluid is higher relatively), perhaps in the drive pattern when the low-speed region at frequent use internal-combustion engine, these advantageous effects are more obvious.

First embodiment's advantageous effects

Sum up the advantageous effects of first embodiment's pump generation below.

(1) vane pump (1) comprising: rotor (6), this rotor are used for rotating by live axle (5), and rotor (6) is included in a plurality of slits (61) of its periphery; A plurality of blades (7), these blade installation and are used for protruding and advancing to the inboard and the outside of this respective slots (61) from corresponding slit (61) in a corresponding slit (61); Cam ring (8), this cam ring is with respect to rotor (6) off-centre, this cam ring (8) surrounding rotor (6); And plate (first or second plate 41 or 42), described plate is arranged to towards the axial end portion of rotor (6), and cooperate with rotor (6), blade (7) and cam ring (8) and to determine a plurality of pump chambers (r), wherein, this plate (first plate 41) comprises in the side facing to rotor (6): suction port (43), this suction port is opened on and sucks in the zone, sucks in the zone at this, and each pump chamber (r) expands when moving together along with the rotation of rotor (6) gradually; Exhaust port (44), this exhaust port is opened in the discharging area, and in this discharging area, each pump chamber (r) shrinks when moving together along with the rotation of rotor (6) gradually; The first back pressure mouth (suction side back pressure mouth 45), this first back pressure mouth is arranged to receive the suction side hydrodynamic pressure, and with corresponding to the proximal part of at least the first slit (61) that sucks first blade (7) in the zone (610, perhaps back pressure chamber br) hydraulic communication; And the second back pressure mouth (46), this second back pressure mouth is arranged to and proximal part (610 corresponding at least the second slit (61) of second blade (7), or back pressure chamber br) hydraulic communication, the distal portions of this second blade (70) are positioned at the end portion (near terminal point B) of suction port (43) and locate; Wherein, the second back pressure mouth (46) comprising: first portion's (back pressure mouth major component 468), this first portion are arranged to receive discharge side liquid pressure; And throttling part (starting end part 462), the fluid that this restriction branch is arranged to be limited between the proximal part (610, or back pressure chamber br) of first portion's (back pressure mouth major component 468) and second slit (61) is mobile.This structure effectively reduces power loss, improves pump operation at low temperatures, and reduces noise level.

(2) in the vane pump according to clauses and subclauses (1), throttling part (starting end part 462) has the substantially invariable cross-sectional flow area of sense of rotation (A) along rotor (6).This feature makes it possible to work as blade 7 by the degree of depth of regulating throttling part (starting end part 462) and moves into the speed V that blade 7 is set when contacting with cam ring 8 at an easy rate.

(3) in vane pump according to clauses and subclauses (1) or (2), second blade (7) also is close to the 3rd blade (7) along the sense of rotation of rotor (6) in three-vaned back, this three-vaned distal portions (70) is positioned between the end (terminal point B) of suction port (43) and the starting end of exhaust port (44) (beginning end points C); And the second back pressure mouth (discharge side back pressure mouth 46) is arranged to pass through in end (B) time before of suction port (43) after proximal part (610, br) beginning and second back pressure mouth (46) hydraulic communication in second slit (61) and at second blade (7), proximal part (610 to second slit (61), or back pressure chamber br) supplies with a certain amount of working fluid at least, wherein, the amount of this working fluid is enough to make that the distal portions (70) of second blade (7) contacts with the interior perimeter surface (80) of cam ring (8).This feature has improved pump operation at low temperatures effectively by effectively preventing blade from connecting stream.

Second embodiment

In first embodiment, when when rotor sense of rotation RD1 sees, throttling part (starting end part 462) has rectangular cross section, and has the substantially constant degree of depth and substantially constant width along rotor sense of rotation RD1, like this, cross-sectional flow area A is along rotor sense of rotation RD1 substantially constant.Also can select, consider the viscosity of working fluid, the density and the other factors of working fluid, the shape of throttling part (starting end part 462) can change, and like this, cross-sectional flow area A changes along rotor sense of rotation RD1, as shown in Figure 12 A to 15.In the example shown in Figure 12 A to 15, the edge 467 of back pressure mouth major component 468 is a rectangle, and not as be semicircle like that among first embodiment.Identical among other parts and first embodiment, therefore, omit explanation to other parts.

In the example shown in Figure 12 A to 15, Fluid Volume ∫ Q is provided with by the cross-sectional flow area A of throttling part (starting end part 462) and the combination of distance L, so as to prevent blade connect stream and blade 7 do not need push, with identical among first embodiment.Because it is constant the cross-sectional flow area of starting end part 462 does not resemble among first embodiment along rotor sense of rotation RD1, therefore, the mean value of the cross-sectional flow area of starting end part 462 (RD1 is average along the rotor sense of rotation) can be provided with Fluid Volume ∫ Q as cross-sectional flow area A.

In a second embodiment, starting end part 462 forms and makes the cross-sectional flow area of starting end part 462 increase along rotor sense of rotation RD1.This feature can be provided with the ejection speed through the blade 7 of starting end part 462 as follows.Figure 12 A to 12D is that second embodiment's the starting end part 462 of version is along the planimetric map of z axial direction.In the example shown in Figure 12 A to 12B, starting end part 462 is arranged to increase along rotor sense of rotation RD1 along the width of rotor radial direction, and the bottom of starting end part 462 (negative z side surface) is flat substantially, and the degree of depth substantially constant of starting end part 462, with identical among first embodiment.But, the width (mean breadth) of considering starting end part 462 is less than the width among first embodiment, and the degree of depth of starting end part 462 is arranged to greater than the degree of depth among first embodiment, and like this, cross-sectional flow area does not reduce.The shape of bottom can change arbitrarily.

In the example of Figure 12 A, when when the z axial direction is seen, the shape of starting end part 462 acutangulates leg-of-mutton shape substantially, and its width increases to predetermined value less than the width of back pressure mouth major component 468 along rotor sense of rotation RD1 gradually with predetermined substantially constant speed.Therefore, when blade 7 process starting end parts 462, the cross-sectional flow area of leading to the passage of back pressure chamber br increases to predetermined value with substantially constant speed gradually from zero.Therefore, the flow velocity Q that supplies with the working fluid of back pressure chamber br increases gradually from zero, and like this, the ejection speed of blade 7 is at first lower, and increases gradually with substantially constant speed.When the such feature of hope, being shaped as of Figure 12 A is preferred.

In the example of Figure 12 B, when when the z axial direction is seen, the shape of starting end part 462 is shape substantially in echelon, and its width gradually increases to predetermined higher value less than the width of back pressure mouth major component 468 with predetermined substantially constant speed from predetermined smaller value along rotor sense of rotation RD1.Therefore, when blade 7 process starting end parts 462, the cross-sectional flow area of leading to the passage of back pressure chamber br increases to predetermined value with substantially constant speed gradually from predetermined smaller value.Therefore, the flow velocity Q of the working fluid of supply back pressure chamber br increases then gradually at first greater than zero, and like this, the ejection speed of blade 7 is at first medium, increases gradually with substantially constant speed then.Compare with the shape of Figure 12 A, this feature is used to shorten makes blade 7 move into the time that contacts with the interior perimeter surface 80 of cam ring 8.When the such feature of hope, being shaped as of Figure 12 B is preferred.

In the example of Figure 12 C, when when the z axial direction is seen, the shape of starting end part 462 becomes the half elliptic shape substantially, its width along rotor sense of rotation RD1 from the zero predetermined higher value that increases to gradually less than the width of back pressure mouth major component 468.It is at first bigger to advance the speed, and reduces then.Therefore, when blade 7 process starting end parts 462, the cross-sectional flow area of leading to the passage of back pressure chamber br increases to predetermined value with such speed gradually from zero, and this speed is at first bigger, reduces then.Therefore, the flow velocity Q that supplies with the working fluid of back pressure chamber br increases fast from zero, slowly increases then, and like this, the ejection speed of blade 7 increases at first fast, slowly increases then.This feature is used to shorten makes blade 7 move into the time that contacts with the interior perimeter surface 80 of cam ring 8, similar with the shape of Figure 12 B.When the such feature of hope, being shaped as of Figure 12 C is preferred.

In the example of Figure 12 D, when when the z axial direction is seen, the combination of the rectangular shape that is shaped as first embodiment of starting end part 462 and the trapezoidal shape of Figure 12 B, its width is at first constant, increases to predetermined value less than the width of back pressure mouth major component 468 along rotor sense of rotation RD1 gradually with predetermined substantially constant speed then.Therefore, when blade 7 during through starting end parts 462, the cross-sectional flow area of passage of leading to back pressure chamber br is at first constant, increases gradually with substantially constant speed then.Therefore, the flow velocity Q of the working fluid of supply back pressure chamber br is at first constant, increases gradually then, and like this, the ejection speed of blade 7 is at first constant, increases gradually with substantially constant speed then.The ejection speed of blade 7 also is not so good as significant change like that in Figure 12 A to 12C example illustrated.Compare for the example of rectangle with starting end part 462, will guarantee that blade 7 is by being pressed on the cam ring 8.When the such feature of hope, being shaped as of Figure 12 D is preferred.

Figure 13 A and 13B are the sectional side views of starting end part 462 of another version of second embodiment.In these versions, the bottom of starting end part 462 tilts along rotor sense of rotation RD1, and like this, starting end part 462 increases along rotor sense of rotation RD1 gradually along the degree of depth of z axial direction.Starting end part 462 along the width of rotor radial direction along rotor sense of rotation RD1 substantially constant.

In the example of Figure 13 A, the bottom of starting end part 462 is by inclined surface peace surface composition, particularly (wherein by first inclined surface, the degree of depth of starting end part 462 gradually increases to predetermined value with substantially constant speed from zero along rotor sense of rotation RD1), middle planar surface (wherein, when when rotor sense of rotation RD1 sees, the degree of depth of starting end part 462 is constant) and second inclined surface is (wherein, the degree of depth of starting end part 462 increases to second predetermined value with substantially constant speed gradually from first value) form, wherein, second inclined surface is connected with back pressure mouth major component 468.The gradient of first inclined surface is greater than the gradient of second inclined surface.Therefore, when blade 7 process starting end parts 462, the cross-sectional flow area of leading to the passage of back pressure chamber br increases to predetermined value with constant rate of speed gradually from zero, and it is constant to become then, increases gradually with substantially constant and slower speed then.Therefore, the flow velocity Q that supplies with the working fluid of back pressure chamber br changes similarly, and like this, the ejection speed of blade 7 increases relatively fast, and it is constant to become then, relatively slowly increases then.This effectively reduces the instantaneous acceleration of blade 7, guarantees that simultaneously blade 7 is by on the interior perimeter surface 80 that is pressed in cam ring 8.When the such feature of hope, being shaped as of Figure 13 A is preferred.The shape of starting end part 462 can change, and the gradient that makes the inclined surface of winning is less than second inclined surface.

In the example of Figure 13 B, the bottom of starting end part 462 is made up of inclined surface, like this, the degree of depth of starting end part 462 with substantially constant speed from zero predetermined value that increases to gradually less than the degree of depth of back pressure mouth major component 468.Therefore, when blade 7 process starting end parts 462, the cross-sectional flow area of leading to the passage of back pressure chamber br increases to predetermined value with constant rate of speed gradually from zero.Therefore, the flow velocity Q that supplies with the working fluid of back pressure chamber br changes similarly, and like this, the ejection speed of blade 7 is at first slower, and quickens gradually, so that increase with substantially constant speed.When the such feature of hope, being shaped as of Figure 13 B is preferred.The shape of the shape of Figure 12 A to 12E and Figure 13 A and 13B can make up, so that obtain the feature of suitable setting.

In a second embodiment, starting end part 462 forms the feature that makes the cross-sectional flow area of starting end part 462 increase gradually along rotor sense of rotation RD1 and is used for effectively blade 7 by the interior perimeter surface 80 that is pressed in cam ring 8.In other words, second embodiment's starting end part 462 is as the part (from beginning end points e to terminal point B) of first embodiment's back pressure mouth major component 468, promptly be used to supply with the extensive work fluid, connect stream so that reliably prevent blade, because second embodiment's starting end part 462 has the cross-sectional flow area bigger than first embodiment's starting end part 462.Therefore, in a second embodiment, the angular orientation of the beginning end points e of back pressure mouth major component 468 can change, so that identical, and can be arranged to equal an about pitch (L0) from the beginning end points c of starting end part 462 to the distance of the beginning end points e of back pressure mouth major component 468 with the angular orientation of the terminal point B of suction port 43.

Second embodiment's advantageous effects

In a second embodiment, throttling part (starting end part 462) has cross-sectional flow area (A), and this cross-sectional flow area (A) increases along the sense of rotation of rotor (6).Except first embodiment's effect, this has also produced and has prevented that further blade from connecting the advantageous effects of stream.

The 3rd embodiment

In the 3rd embodiment, starting end part 462 forms like this, makes the cross-sectional flow area of starting end part 462 reduce gradually along rotor sense of rotation RD1.This feature can be provided with the ejection speed of this blade 7 when blade 7 process starting end parts 462.Figure 14 A to 14D is the planimetric map of starting end part 462 of the 3rd embodiment's version.In these examples, starting end part 462 is arranged to reduce along rotor sense of rotation RD1 along the width of rotor radial direction.Identical among the bottom shape of starting end part 462 and the degree of depth and second embodiment shown in Figure 12 A to 12E.

In the example of Figure 14 A, when when the z axial direction is seen, the combination that is shaped as basic circular end sections and basic rectangle part of starting end part 462, wherein, when along rotor sense of rotation RD1, starting end part 462 increases fast in the rounded ends part and reduces along the width (cross-sectional flow area of leading to the passage of back pressure chamber br) of rotor radial direction, becomes constant then in rectangle part.Therefore, when blade 7 process starting end parts 462, the flow velocity Q of the working fluid of supply back pressure chamber br is to change with the similar mode of the width of starting end part 462, and like this, the ejection speed of blade 7 increases at first fast and reduces, and substantially constant then becomes.When the such feature of hope, being shaped as of Figure 14 A is preferred.

In the example of Figure 14 B, when when the z axial direction is seen, starting end part 462 be shaped as the fundamental triangle shape, this is leg-of-mutton towards opposite with the triangle of Figure 12 A, wherein, when along rotor sense of rotation RD1, starting end part 462 gradually is reduced to zero with substantially constant speed from predetermined value (this predetermined value is less than the width of back pressure mouth major component 468) along the width (cross-sectional flow area of leading to the passage of back pressure chamber br) of rotor radial direction.Therefore, when blade 7 process starting end parts 462, the flow velocity Q of the working fluid of supply back pressure chamber br is to change with the similar mode of the width of starting end part 462, like this, the ejection speed of blade 7 is quick at first relatively, is reduced near zero value with substantially constant speed then.When the such feature of hope, being shaped as of Figure 14 B is preferred.

In the example of Figure 14 C, when when the z axial direction is seen, starting end part 462 be shaped as basic half elliptic shape, this is half elliptic towards opposite with the half elliptic of Figure 12 C, wherein, when along rotor sense of rotation RD1, starting end part 462 is reduced to zero along the width (cross-sectional flow area of leading to the passage of back pressure chamber br) of rotor radial direction gradually from predetermined value (this predetermined value is less than the width of back pressure mouth major component 468).The speed that reduces is less at first relatively, relatively large at last.Therefore, when blade 7 process starting end parts 462, the flow velocity Q of the working fluid of supply back pressure chamber br is to change with the similar mode of the width of starting end part 462, like this, the ejection speed of blade 7 is quick at first relatively, slowly reduces earlier then, reduces fast again.When the such feature of hope, being shaped as of Figure 14 C is preferred.

In the example of Figure 14 D, when when the z axial direction is seen, the combination that is shaped as triangle and rectangle of starting end part 462, this combination towards opposite with the shape of Figure 12 D, wherein, when along rotor sense of rotation RD1, starting end part 462 gradually is reduced to zero from predetermined value (this predetermined value is less than the width of back pressure mouth major component 468) with substantially constant speed along the width (cross-sectional flow area of leading to the passage of back pressure chamber br) of rotor radial direction, begins substantially constant then.Therefore, when blade 7 process starting end parts 462, the flow velocity Q of the working fluid of supply back pressure chamber br is to change with the similar mode of the width of starting end part 462, like this, the ejection speed of blade 7 is quick at first relatively, reduces with substantially constant speed then, and it is constant to become then.When the such feature of hope, being shaped as of Figure 14 D is preferred.

Figure 15 has represented another version of the 3rd embodiment, wherein, the bottom angled of starting end part 462, like this, starting end part 462 reduces along rotor sense of rotation RD1 gradually along the degree of depth of z axial direction.Along rotor sense of rotation RD1, the width substantial constant of starting end part 462 on the rotor sense of rotation.Specifically, when along rotor sense of rotation RD1, the degree of depth of starting end part 462 is reduced near zero value from predetermined value (being slightly less than the degree of depth of back pressure mouth major component 468) gradually with substantially constant speed.Therefore, when blade 7 process starting end parts 462, the cross-sectional flow area of leading to back pressure chamber br is reduced near zero value gradually from predetermined value, therefore, the flow velocity Q that supplies with the working fluid of back pressure chamber br changes similarly, like this, the ejection speed of blade 7 is quick at first relatively, is reduced near zero value with substantially constant speed then.When the such feature of hope, being shaped as of Figure 15 is preferred.The shape of starting end part 462 can change similarly with second embodiment shown in Figure 13 A, and like this, planar surface in the middle of inclined surface is formed with is so that reduce the instantaneous retardation of blade 7.The shape of Figure 14 A to 14E and the shape of Figure 15 can make up, so that obtain the feature of suitable setting.

In the 3rd embodiment, at the early stage of the ejection campaign of blade 7, the most of working fluid that is used for making blade 7 contact (being used to the primary clearance of blade 7 between blade 7 and cam ring 8 advanced) aequum with cam ring 8 is supplied with back pressure chamber br.This can shorten the length (distance L) of starting end part 462 along rotor sense of rotation RD1.On the other hand, the feature that reduces in the terminal stage (in this terminal stage, blade 7 moves into cam ring 8 and contacts) of the ejection campaign of blade 7 of the ejection speed of blade 7 is used for effectively reducing the noise that the contact owing to blade 7 produces.The 3rd embodiment's starting end part 462 forms like this, the cross-sectional flow area of starting end part 462 reduces gradually along rotor sense of rotation RD1, therefore, compare with first and second embodiments, the fluid connection between starting end part 462 and back pressure mouth major component 468 is restricted.Therefore, even when working fluid begins to supply to the back pressure chamber br that is used for blade 7 from starting end part 462, thereby when making pressure in the starting end part 462 reduce fast, prevent that also the pressure in back pressure mouth major component 468 from changing (reduction) fast, because working fluid is restricted from the flow velocity that back pressure mouth major component 468 leaks to starting end part 462 (being used for replenishing the amount of supplying with back pressure chamber br).Therefore, with identical among first embodiment, the 3rd embodiment's starting end part 462 also is used for preventing the pressure surge or the pulsation of back pressure mouth major component 468, thus the stable pressure of supplying with blade 7 from back pressure chamber br (this back pressure chamber br is connected with back pressure mouth major component 468 hydraulic pressure).

The 3rd embodiment's advantageous effects

In the 3rd embodiment, throttling part (starting end part 462) has cross-sectional flow area (A), and this cross-sectional flow area (A) reduces along the sense of rotation of rotor (6).Except first embodiment's effect, this feature also produces the advantageous effects that has improved noise reduction effect.

First to the 3rd embodiment can followingly change.It not is that the fluid of oil (ATF) is as working fluid that pump 1 can use.Extend although blade 7 (or slit 61) forms along the rotor radial direction, blade 7 (or slit 61) also can form with respect to the rotor radial direction and extend obliquely.

Discharge side back pressure mouth 46 parts (part that comprises starting end part 462) in sucking regional RE1 are arranged with the discharge side back pressure mouth 46 part branches in discharging area RE2.In other words, discharging side back pressure mouth 46 can implement like this: first mouthful, be arranged to receive to discharge side liquid pressure, and with proximal part (610, back pressure chamber br) hydraulic communication corresponding at least the first slit (61) of first blade (7) in the discharging area (RE2); Second mouthful, be arranged to receive to discharge side liquid pressure, and proximal part (610, the back pressure chamber br) hydraulic communication of at least the second slit (61) of second blade of locating with the end portion (B) that is positioned at suction port (43) corresponding to distal portions (70) (7).

The whole contents of Japanese patent application 2010-000528 (applying date is on January 5th, 2010) and Japanese patent application 2010-062861 (applying date is on March 18th, 2010) is incorporated herein by reference.

Although introduced the present invention with reference to specific embodiment of the present invention above, the present invention is not limited to the foregoing description.Those skilled in the art will know the variation and the change of the foregoing description according to above-mentioned instruction.Scope of the present invention will be determined with reference to following claim.

Claims

1. vane pump comprises:

Rotor, this rotor is suitable for rotating by live axle, and rotor is included in a plurality of slits of the periphery of this rotor;

A plurality of blades, these blade installation and protrude and advance to the inboard and the outside of this respective slots from corresponding slit in corresponding slit;

Cam ring, this cam ring be with respect to rotor eccentricity, this cam ring surrounding rotor; And

Plate, this plate is arranged to the axial end portion towards rotor, and cooperates definite a plurality of pump chambers with rotor, blade and cam ring, and wherein, this plate comprises in the side facing to rotor:

Suction port, this suction port are opened on and suck in the zone, suck in the zone at this, and each pump chamber expands when moving together along with the rotation of rotor gradually;

Exhaust port, this exhaust port is opened in the discharging area, and in this discharging area, each pump chamber shrinks when moving together along with the rotation of rotor gradually;

The first back pressure mouth, this first back pressure mouth is arranged to receive the suction side hydrodynamic pressure, and with proximal part hydraulic communication corresponding at least the first slit that sucks first blade in the zone; And

The second back pressure mouth, this second back pressure mouth are arranged to and proximal part hydraulic communication corresponding at least the second slit of second blade, and the distal portions of this second blade is positioned at the terminal part office of suction port, and wherein, the second back pressure mouth comprises:

First portion, this first portion are arranged to receive discharge side liquid pressure; And

The fluid that throttling part, this restriction branch are arranged to be limited between the proximal part of the first portion and second slit flows.

2. vane pump according to claim 1, wherein: the cross-sectional flow area of throttling part is along rotor sense of rotation substantially constant.

3. vane pump according to claim 1, wherein: the cross-sectional flow area of throttling part increases along the rotor sense of rotation.

4. vane pump according to claim 1, wherein: the cross-sectional flow area of throttling part reduces along the rotor sense of rotation.

5. according to any one described vane pump in the claim 1 to 4, wherein:

In three-vaned back and contiguous the 3rd blade, this three-vaned distal portions is between the starting end of the end of suction port and exhaust port along the sense of rotation of rotor for second blade; And

The second back pressure mouth be arranged to proximal part at second slit begin with the second back pressure mouth hydraulic communication after, in time before second vanes is crossed the end of suction port, proximal part to second slit is supplied with a certain amount of working fluid at least, wherein, the amount of this working fluid is enough to make that the distal portions of second blade contacts with the interior perimeter surface of cam ring.

6. according to any one described vane pump in the claim 1 to 4, wherein:

Each blade extends along the rotor radial direction; And

The second back pressure mouth overlaps along the circumferential direction and the suction port of plate.

7. vane pump according to claim 1, wherein: the cross-sectional flow area of throttling part changes along the rotor sense of rotation.

8. vane pump according to claim 7, wherein: the cross-sectional flow area of throttling part changes along the degree of depth of throttling part.

9. according to any one described vane pump in the claim 1 to 4, wherein: throttling partly has the degree of depth littler than first portion.