CN102439312A

CN102439312A - Compact eccentric radial piston hydraulic machine

Info

Publication number: CN102439312A
Application number: CN201080023618XA
Authority: CN
Inventors: D·B·史蒂芬森; P·K·拉杰普特
Original assignee: Husco International Inc
Current assignee: Husco International Inc
Priority date: 2009-05-26
Filing date: 2010-05-25
Publication date: 2012-05-02
Also published as: WO2010138509A1; US20120111185A1

Abstract

A high efficiency diametrically compact, radial oriented piston hydraulic machine includes a cylinder block with a plurality of cylinders coupled to a first port by a first valve and to a second port by a second valve. A drive shaft with an eccentric cam, is rotatably received in the cylinder block and a cam bearing extend around the eccentric cam. A separate piston is slideably received in each cylinder. A piston rod is coupled at one end to the piston and a curved shoe at the other end abuts the cam bearing. The curved shoe distributes force from the piston rod onto a relatively large area of the cam bearing and a retaining ring holds each shoe against the cam bearing. The cylinder block has opposing ends with a side surface there between through which every cylinder opens. A band engages the side surface and closes the openings of the cylinders.

Description

Compact eccentric radial piston hydraulic press

The cross reference of related application

The rights and interests that No. the 61/181st, 117, the U.S. Provisional Patent Application that the application requires to submit on May 26th, 2009.

Statement about federation's patronage research and development

Inapplicable

Technical field

The present invention relates to the hydraulic press such as pump and fluid power motor, and more properly relate to this kind hydraulic press with the piston that is resisted against the motion of eccentric shaft radial ground.

Background technique

Usually the radial piston pump of type comprises body, and this body has a plurality of cylinders, and these cylinders radially are provided with and are used to hold piston around live axle.Admitting slidably in each cylinder has piston, limits chamber in cylinder interior thus.Axle has centrifugal cam, and piston is biased to ride by spring and is against cam, and between piston and cam, has the line contact.The piston of conventional pump and the contact of the line between the eccentric cam limit the bearing capacity of this device, and on the interface in piston and hole, moment are set.Ingress port applies the fluid to inlet channel, and this inlet channel is connected in each cylinder chamber through independent inlet non-return valve.One group of outlet non-return valve is connected in cylinder chamber the outlet passage that causes the delivery side of pump port.

Along with live axle is rotated by exterior motor or motor, the eccentric cam cause piston slips into and skids off cylinder circularly, reduces and enlarge the volume of respective cylinder chamber thus.In the charging stage of each piston cycle process, when given cylinder chamber volume enlarged, inlet check valve was opened, and makes fluid to be drawn out of and to get into cylinder chamber from inlet passage.In each piston cycle exhaust phase process subsequently, when the volume of cylinder chamber reduced, fluid was under pressure through the outlet non-return valve discharge and through the outlet port.In each rotary course of eccentric cam, fluid sucting stage and discharge stage take place times without number.Point at any time, some in the cylinder that radially is provided with are in sucting stage, and other cylinder is in the discharge stage.When traditional safety check pump was in total travel, noise level was relatively low, and this is the high pressure measurement noise of being found owing in valve plate that does not have axial and outside radial piston eccentric pump and motor or the pivot metering.

Traditional radial piston pump general diameter is relatively large, to hold bias spring and the plunger that the outer end of each cylinder is closed.In many installation situations, the amount of space that is used for pump is limited, therefore hopes to reduce the size of pump.Or rather, many times, pump is installed in by motor or the gearbox, and radial space is limited, thereby hinders the installation of conventional radial reciprocating pump.

Another problem relevant with radial piston pump is: when live axle rotated, moment was applied on the bar of each piston.This moment produces the side force that piston is pushed against cylinder wall, and piston slides in this cylinder.This side force hinders the piston slip and is unfavorable thus.

The added efficiency problem relevant with inner radial piston eccentric pump is owing to following demand produces: housing need be full of fluid, to be used for discharge capacity control or to be used for the sliding friction surface lubrication.Adopt complete crankcase, the eccentric cam of rotation can meet with the remarkable windage loss that causes this unit efficiency to reduce.Another benefit be except the little year piston that carries out hole motion, this design of not having a sliding friction element can be used in the oil of low lubricity, and even utilizes the liquid such as water reducing use pressure under.The present invention is through providing the radially-compact property that is described below, the specific power of enhancing and the problem that improvement efficient solves existing pump.

Summary of the invention

Novel hydraulic press comprises cylinder block, and this cylinder block has two end faces, and between these two end faces is the side.First port and second port are formed in the cylinder block, are used for being connected with the hydraulic pressure of this cylinder block.A plurality of cylinders radially are arranged in the cylinder block, and each cylinder has the opening that passes the side.Zonula occludens cooperates with outer surface and the opening of a plurality of cylinders is closed.Admit independent piston assembly slidably in each cylinder in a plurality of cylinders.Live axle rotatably is received in the cylinder block and has eccentric cam, in order to drive a plurality of cylinders in a plurality of cylinders.

An aspect of hydraulic press provides at least one valve that is associated with each cylinder, controls so that the fluid between each port in the cylinder and first and second ports is flowed.In one embodiment, a plurality of first holes are formed in one of surface, and a plurality of second hole is formed on same or another end face in.A plurality of first valves are arranged in first hole, and between the cylinder in first port and a plurality of cylinder fluid passage are provided optionally.A plurality of second valves are arranged in second hole, and between the cylinder in second port and a plurality of cylinder another fluid passage are provided optionally.In a pattern, each valve in first and second valves all is a passive type.In another pattern, each valve in first and second valves be electric operation and preferably two position two-way valve.

In another embodiment, a plurality of holes are formed in first end face.A plurality of three-way valve are arranged in first hole, and cylinder and the fluid passage between first and second ports in a plurality of cylinders optionally are provided.In a preferred form, each three-way valve is the three-position valve of electric operation.

Being on the other hand of hydraulic press of the present invention: each piston assembly comprises the piston that is connected with piston rod.This piston rod comprises the bar with curved plate, and this curved plate has a surface, and power puts on eccentric cam through this surface.The surface of piston rod base plate has the surface area bigger than the maximum cross-section area of bar.Base plate will be distributed in from the power of piston rod on the bigger zone of eccentric cam, allow higher load-bearing thus.Retaining ring cooperates around the live axle extension and with the curved plate of each piston rod, and each piston rod is kept towards eccentric cam.This retaining ring is eliminated the demand for spring, and this spring is with in the hydraulic press formerly, so that piston or piston rod biasing are resisted against the live axle cam.

Also described be used for piston rod be connected in piston, with some replacement device of the lateral force between the wall that reduces piston and cylinder.These lateral forces are tending towards hindering the slip of piston in cylinder.

Description of drawings

Fig. 1 is the schematic representation that comprises according to the open-loop hydraulic system of radial-piston motor hydraulic press of the present invention;

Fig. 2 is cylinder and the radial cross-section of piston structure that illustrates in the hydraulic press;

Fig. 3 is the axial sectional view that cuts open the radial piston hydraulic press of getting along Fig. 2 Vertical Centre Line 3-3;

Fig. 4 is the part radial cross-section that second kind of structure of piston and piston rod is shown;

Fig. 5 is the part radial cross-section of the third structure of explanation piston and piston rod;

Fig. 6 is the part radial cross-section of a modification embodiment illustrated in fig. 3, and the entrance and exit safety check that wherein is used for each cylinder is arranged in the same hole of the cylinder block of hydraulic press;

Fig. 7 is the schematic representation of a kind of pattern of hydraulic press, and this hydraulic pressure function is operated motor in a bi-directional way;

Fig. 8 is the schematic representation that comprises the hydraulic system of a kind of pattern of hydraulic press according to the present invention, and this hydraulic press not only can be used as pump but also can be used as motor and comes work;

Fig. 9 is the axial sectional view of radial piston hydraulic press, and this hydraulic press uses a pair of bi-bit bi-pass guiding valve to control the fluid inflow and flows out each cylinder; And the closed loop ability is provided and makes the hydraulic pressure function not only work as pump but also as motor; And

Figure 10 is the axial sectional view of radial piston hydraulic press, and this hydraulic press uses single 3-position-3-way guiding valve to control the fluid inflow and flows out each cylinder.

Embodiment

Referring to Fig. 1, open-loop hydraulic system 10 has the prime mover 12 such as internal-combustion engine or motor, and this prime mover 12 is connected by axle, to drive hydraulic press 14, it is worked as pump.Hydraulic press 14 can be configured to the pump of fixed displacement, with suction fluid from first conduit 15, and forces this fluid under pressure, to get into second conduit 16, drives fluid power motor 18 along a direction thus.Fluid power motor 18 for example makes one or two wheel 20 rotations of vehicle.

Same hydraulic press design also can be used as the fluid power motor such as fluid power motor 18.At this, hydraulic press receives pressure fluid a port, and converts this fluid dynamic to mechanical energy, and this mechanical energy is applied in the axle that is connected in wheel 20.

Therefore, be called as on the outfit of equipment described herein by " hydraulic press ", this is because how and wherein this equipment can be configured to work as pump and fluid power motor according in hydraulic system, using.In some cases, whether some hydraulic presses can drive load such as wheel 20 according to this hydraulic press and still for example slide when stopping at vehicle and driven by load and come work as pump and motor in difference the time.

Referring to Fig. 2 and 3, hydraulic press 14 has cylinder block 30, and this cylinder block 30 has outside first and

second end faces

21 and 22, and extend between these two end faces annular, outer side 38.Cylinder block 30 has ingress port 28 and outlet port 29, and

conduit

15 and 16 is connected to this two ports.Ingress port is connected to annular entry and

outlet passage

31 and 32 with

outlet port

28 and 29, and this entrance and

exit passage

31 and 32 extends through cylinder block around central shaft hole 41 roundedly, and this central shaft hole 41 extends through this cylinder block 30.Three cylinders 36 extend radially outwardly from central shaft hole 41, and directed with 120 degree increment ground around this central shaft hole.Though illustrated embodiment has three cylinders 36, in fact hydraulic press 14 can have the cylinder of greater number, moment of torsion, flow and pressure surge when working to reduce hydraulic press.Each cylinder 36 comprises tubular sleeve 39, and this sleeve is inserted in the hole in the cylinder block 30.Though sleeve 39 helps reducing the diameter of hydraulic press 14, like what will describe, be used for cylinder block through the material that can be processed to form cylinder, can cancel this sleeve.Each cylinder 36 has opening, and this opening passes the side 38 of cylinder block 30.Seal cup 24 with O shape circle is placed on each opening inboard, and 38 extensions around the side of band shape closed ring 35, and closes tightly each opening in the cylinder opening.Continuously closed ring 35 is eliminated in the conventional pump design from each cylinder outwards outstandingly relatively than long-plunger, reduces the integral diameter of hydraulic press 14 thus.

Specifically referring to Fig. 3, a plurality of first holes 26 extend in first end face 21 of cylinder block 30, and each hole is opened in inlet channel 31 and the cylinder 36 in the corresponding cylinder.Independent inlet non-return valve 33 is arranged in each place, first hole in those first holes 26.When the pressure in the inlet channel 31 during greater than the pressure in the cylinder chamber 37, inlet non-return valve 33 is opened, and this can take place at sucting stage of pumping circulation.A plurality of second holes 27 extend in second end face 22 of cylinder block 30, and each second hole is opened in inlet channel 31 and the cylinder 36 in the corresponding cylinder.Independent outlet non-return valve 34 is arranged in each place, second hole in those second holes 27.When the pressure in the cylinder chamber 37 during greater than the pressure in the outlet passage 32, outlet non-return valve 34 is opened, and this takes place in the discharge stage of pumping circulation usually.Inlet non-return valve and outlet non-return valve 33 with 34 structurally with function on be used in conventional pump in the safety check of similar type identical.It should be understood that inlet channel and

outlet passage

31 and 32 with pump in all piston-cylinders be communicated with, and identical paired safety check is provided for each cylinder.In inlet non-return valve and outlet

non-return valve

33 and 34 each is passive type, this means this safety check in response to apply on it pressure but not by the electric actuator work such as solenoid.

The tubular sleeve 39 that partly forms cylinder 36 makes inlet non-return valve and outlet

non-return valve

33 and 34 can be placed to more the longitudinal axis 25 near live axle 40.Notice that inlet non-return valve and outlet

non-return valve

33 and 34 are positioned at the arcuate perimeter of closing, and this arcuate perimeter is limited 38 of the exterior lateral sides of cylinder block 30.In existing structure, valve must be outside from the upper dead center position of piston, to receive the fluid that from cylinder chamber 37, is ordered about out.As shown in Figure 3, tubular sleeve 39 is in cylinder chamber 37 and wherein locate the upper opening portion branch extension between the hole that safety check 33 and 34 are arranged, and cylinder-bore is extended in the cylinder chamber 37 further.

Simultaneously referring to Fig. 2 and 3, live axle 40 extends through axis hole 41, and can rotate therein, by 42 supportings of pair of bearings once more.The center section of live axle 40 in cylinder block 30 has eccentric cam 44.This cam 44 has rounded outer surface, and the axis 25 of the remainder 43 of the center line of this cam and live axle 40 departs from.So when live axle 40 rotated in cylinder block 30, cam 44 was with axis 25 rotations of eccentric manner around live axle.Illustrate particularly like Fig. 2, camshaft bearing 46 extends around the cam 44 of live axle 40.Camshaft bearing 46 has inner race 47 and outer race 48, and this inner race is pressed against on the outer periphery face of cam.A plurality of rollers 49 are between inner race and outer race 47 and 48.In a preferred embodiment,, this inner race 47 is cancelled through axle 40 being carried out suitably heat treatment and processing with as inner race.With respect to using plain friction bearing to realize the traditional pump and the motor of this function, camshaft bearing 46 has improved the efficient of hydraulic press.Though the camshaft bearing 46 with cylindrical roller is shown, also can uses bearing with sphere or other type roller.

Piston assembly 51 is received in each cylinder in the cylinder 36 slidably.Each piston assembly 51 comprises piston 52 and piston rod 54.Piston rod 54 extends between piston 52 and camshaft bearing 46.Piston rod 54 has curved plate 56, and this curved plate abuts the outer race 48 in camshaft bearing 46.Base plate 56 is wideer than the axle of piston rod, to produce flange portion.A pair of annular retaining ring 58 extends around cam 44, and cooperates with the flange portion of each piston rod base plate 56, and piston rod 54 is held against in camshaft bearing 46, and this is especially favourable in the suction stroke part process of pumping circulation.Curved plate 56 is evenly distributed in piston load on the outer race 48 of camshaft bearing 46, and also local load is distributed on the roller 49 of this bearing.Base plate 56 distributed load on the zone of broad is compared with traditional pump or motor, and this can prolong bearing life and help to improve the compactedness and the rated pressure ability of entire machine design.To be that when live axle 40 and cam 44 rotated in cylinder block 30, the outer race 48 of camshaft bearing 46 kept static relatively in greater detail.Outer race 48 is to compare quite low speed rotation with the speed of live axle.Therefore, between the outer race 48 of each piston base plate 56 and camshaft bearing, almost there is not relative movement.

Piston 52 is and has the cup-shaped of internal cavities 53, and this internal cavities is towards live axle 40 openings.The end of piston rod 54 is received in the internal cavities 53 and has the spherical head 60 of part, and this head 60 is assembled in the part bulb-shaped recess portion 62 that is complementary in the piston 52.The head of piston 52 can have the hole 50 of running through head, to transmit hydraulic fluid from cylinder chamber 37, lubricates the interface between spherical head 60 and the piston 52.Piston rod 54 is held against in piston 52 by the single lining of opening or split bushing 55 and snap ring 57, and this snap ring leans against in the internal groove in the internal cavities 53 of piston.When piston rod 54 was followed the eccentric motion of cam 44, piston 52 was also followed this eccentric motion through the slip in cylinder 36.Put on 54 last times of piston rod when rotatablely moving through the rotation of cam 44, lining and snap ring structure make the spherical head 60 of piston rod to pivot with respect to piston 52.Because this kind pivot, rotatablely moving is not delivered in the piston 52, makes that thus the lateral force between the wall of piston and cylinder 36 is minimum.

Fig. 4 illustrates the substitute machine 70 that is used for piston rod 54 is fixed in the inside of piston 52.Such as previous embodiment, the part spherical head 60 of piston rod 54 is assembled in the coupling depressed part 62 in the end face 61 of internal piston cavity 53.Annular groove 72 separates around internal cavities 53 extensions and with end face 61.Volute spring 74 has than big end and smaller end, should lean against in the annular groove 72 big end, and smaller end cooperates around the piston rod extension and with the spherical head 60 of piston rod 54.Volute spring 74 is biased to spherical head 60 with piston 52 and cooperates, and makes these two parts keep abutting each other thus.Therefore, when the rotation of cam 44 with piston rod 54 along shown in Figure 4 towards when drop-down, spring 74 with piston rod to drop-down piston 52.

Fig. 5 illustrates another alternate embodiment, and wherein piston and piston rod are configured to single metal spare.At this, piston 80 is assemblied in the circular cylinder 36 along having circular cross section in the plane transverse to the figure paper plane thus.Yet the annular surface 82 that cooperates with the wall of cylinder 36 has spheric profile, thereby can pivot with respect to the axis of cylinder 36, and still keeps and the closely cooperating of cylinder.This kind pivotal capability can adapt to piston rod slightly waving when cam 44 rotations.Annular surface 82 has Sealing 84, to guarantee the fluid-tight engagement with cylinder wall.

In this embodiment, piston rod 86 is integral and extends downward curved plate 88 with piston 80, and this curved plate 88 abuts in the outer surface of the outer race 48 of camshaft bearing 46.At least one annular retaining ring 58 is held against in outer race 48 piston rod base plate 88.Therefore, when cam 44 rotated in cylinder block 30 prejudicially, the piston 80 of piston rod 86 and one was pushed and spurs along cylinder 36.Through adapting to slightly waving of piston rod, make that lateral force or the sidepiece load between piston and the cylinder is minimum.

Get back to Fig. 3, live axle 40 comprises internal lubrication passage 64, and this internal lubrication passage extends to outer surface from an end of cam 44.This lubrication channel 45 in the center on the eccentric summit of cam, in this outer surface, have a single opening, with fluid feed in camshaft bearing 46.The other end of lubrication channel 64 is opened in the chamber 66 at the place, end of live axle 40, and this chamber receives the fluid of relatively low pressure from inlet channel 31 through feed throughs 68.When live axle 40 rotations, centrifugal force makes fluid be discharged to the camshaft bearing 46 from lubrication channel 64.This kind effect pumps to additive fluid the lubrication channel 64 from chamber, and the pump function of camshaft lubrication being held 46 fluid is provided thus.If camshaft bearing 46 has inner race 47, this inner race has the hole that lubricating fluid is sent to roller 49.Outer race 48 also has through hole, comes the base plate 56 of piston rod 54 is lubricated, and splash lubrication is provided thus and eliminates the needs that central shaft hole 41 are full of fluid.Do not make crank pin be full of fluid, the efficient that this can reduce the resistance of air on the eccentric cam 44 and improve hydraulic press.Additional lubrication channel 59 is provided, fluid is sent to the conical bearing 42 of live axle 40 from axis hole 41.The fluid that is used to lubricate is acentric axis hole 41 through the outfall 69 of standard, and fluid is sent to the storage tank that is used for hydraulic system from this outfall.

Cylinder block 30 shown in Figure 3 has the

hole

26 and 27 of separation, and these two holes are inwardly outstanding from relative first and

second end faces

21 and 22, and inlet non-return valve and outlet non-return valve are received in these two holes.Fig. 6 illustrates alternate design, and the end face of wherein single hole 90 from those end faces is outstanding.In illustrated example, this single hole 90 opening 91 from first end face 21 extends through inlet channel 31 and the cylinder 36 that is associated, and on opposite side, ends at the opening that gets into outlet passage 32.Yet single hole also can extend to inlet channel 31 from second end face 22.

Outlet non-return valve 34 comprises the first valve element 92 with valve rod 93, and this valve rod extends in the guiding blind hole 94 in the cylinder block 30.Annular first valve seat 95 is press fitted in the hole 90 between outlet passage 32 and the cylinder 36.Spiral compression spring 96 is biased to the first valve element 92 with first valve seat 95 and cooperates.

At the opposite side of cylinder 36, inlet valve 33 is press fitted in the hole 90 between inlet channel 31 and the cylinder.Inlet valve 33 comprises the second valve element 97, and this second valve element is biased to second valve seat 98 by second spring 99 and cooperates.Inlet non-return valve and outlet

non-return valve

33 and 34 all are inserted in the hole 90 through the opening 91 in second end face 22.

Hydraulic press 14 shown in Fig. 2 and 3 can be used for driving motor 18 along arbitrary sense of rotation.In this embodiment shown in Figure 7, two-position three way directional control valve 130 is connected in first and

second conduits

15 and 16 with the ingress port of hydraulic press 14 with

outlet port

28 and 29, and this first and second conduit is connected in motor 18.According to the position of directional control valve 130, inlet channel 31 is connected in a conduit in first and

second conduits

15 and 16, and outlet passage 32 is connected in another conduit in those conduits.Controller 122 these electric hydaulic directional control valves 130 of operation.

Fig. 8 illustrates another hydraulic system 100, and this hydraulic system is used the two-way embodiment of the hydraulic press 114 that is driven by prime mover 112.Hydraulic press 114 can be configured to the two-way pump of fixed displacement, this two-way pump controlled with force fluid along arbitrary direction through

conduit

115 and 116, and conduit is connected in bidirectional hydraulic motor 118, this bidirectional hydraulic motor for example makes the wheel 120 of vehicle rotate.This hydraulic press 114 dynamically is configured to from

arbitrary conduit

115 or 116, extract fluid out, and forces fluid under pressure, to get into another conduit, drives motor 118 along arbitrary direction thus.The operation of the hydraulic press 114 that will hereinafter be described is by 122 management of controller, and these controller 122 receptions are from the order of operator input device 124.

The details of a pattern of the bidirectional hydraulic machine in can be used on hydraulic system 100 shown in Fig. 9.Therefore hydraulic press 200 has and Fig. 2 and hydraulic press shown in Figure 3 14 similar essential structures, and the same parts in two hydraulic presses has been denoted as identical reference character.Exactly, a plurality of cylinders radially extend and pass annular, outer side 204 and the opening of cylinder block 201.Significant difference is: the

passive check valve

33 and 34 that hydraulic press 200 uses electro-hydraulic bi-bit bi-pass guiding valve 202 and 204 to substitute in the aforementioned hydraulic machine.

Each bi-bit bi-pass first valve 202 extends in independent first hole 209 in first end face 203 of cylinder block 201.First valve 202 has spool 206, and these spool 206 convection cells are through mobile control of first hole 209 between cylinder chamber 37 and annular first passage 221, and should be communicated with first port, 224 fluids by annular first passage 221.This first valve 202 has first solenoid 208, and this first solenoid 208 moves spool 206 between the opening and closing position, and its motion mode is the effect that is replicated in first safety check 33 among the hydraulic press embodiment shown in Figure 3.Controller 122 based on microcomputer drives first solenoid 208 in response to the signal from sensor 210, and the position of this signal indication live axle 40.

Each bi-bit bi-pass second valve 204 extends in independent second hole 211 in second end face 205 of cylinder block 205.Second valve 204 will be between cylinder chamber 37 and annular second channel 222, the path through second hole 211 optionally opens and closes, and should be communicated with second port, 226 fluids by annular second channel 222.This second valve 204 has second solenoid 214, and this second solenoid 214 moves second spool 212 in second hole 211, opens and closes the position to be controlled to be, and its motion mode is the effect of duplicating second safety check 34 shown in Figure 3.Controller 122 is also operated this second solenoid 214.First and second valves 202 and this kind operation of 204 are pumped to second port 226 with fluid from first port 224.Notice, first and second valves 202 and 204 spool 206 and 212 in each cyclic process between the outermost position of the head of drive axis 25 and piston 52.At this outermost position shown in Fig. 9.First and second valves 202 and 204 spool 206 and 212 are parallel to axis 25 orientations of live axle 40, that is to say, spool moves along paralleling to the axis.This kind orientation further reduces the integral diameter of hydraulic press 200.

First and second holes 209 with 211 usually with their related cylinder 36 coplanes.For compacter on the longitudinal axis size, first and second holes 209 and 211 and thus wherein first and second electro-hydraulic valves 202 and 204 can depart from out and between two adjacent cylinder.

Operate this to electro-hydraulic valve 202 and 204, with duplicate substantially embodiment illustrated in fig. 3 in two

safety check

33 and 34 effect.Yet when pumping circulation finished, promptly when the transition of discharge stage and sucting stage, first and second electro-hydraulic valves 202 and 204 all cut out, and this causes the power of cylinder pressure decompression to be sent on the live axle 40.In existing pump, the pressure that the discharge stage remains in the cylinder when finishing is discharged in the inlet channel 31 when inlet valve is opened.This has two unfavorable effects, at first, has back pressure to be fed in the inlet channel, thereby influence is in other cylinder air-breathing of sucting stage, and secondly, decompression can produce significant operational noise.These unfavorable effects are eliminated through the following technology of the present invention: wherein the power with the cylinder pressure decompression is sent on the live axle 40.

Except the effect of duplicating in the embodiment shown in fig. 3 two

safety check

33 and 34; Operate this to electro-hydraulic valve 202 and 204 with opposite way; Make the fluid that flows through pump flow to first port 224, ingress port and outlet port are put upside down from second port 226.This kind reverse operating makes that hydraulic press 200 can two-way ground pumping fluid.Adopt bidirectional operation,, thereby need be used to supply with independent the 3rd port 228 of lubricating fluid because port 224 or 226 any one can have high relatively pressure as the outlet port time.

The control of this kind selectivity two-way valve also makes hydraulic press 200 can be used as motor.For example, when the vehicle among Fig. 7 slides when stopping, wheel 120 drives motors 118, forces fluid to be back to hydraulic press 114.Through hydraulic press 114 is configured to as the motor effect, the energy in recyclable this fluid also replenishes to prime mover 112.For the hydraulic press among Fig. 9 200 is configured to work as motor; No matter in first or second valve 202 or 204 which is associated with the port 224 or 226 of reception from the pressure fluid of motor 118, open this valve by controller 122 at the sucting stage of piston cycle.This makes the pressurized stream physical efficiency get into cylinder chamber 37 and power is applied on the piston 52, to drive eccentric cam 44 rotatably and to drive whole live axle 40 thus.When piston 52 arrives lower dead point positions and carries out the transition to discharge during the stage, the valve 202 or 204 of first front opening cuts out, and in those valves another opened.Therefore, in the discharge stage, fluid is displaced the another port 226 or 224 of cylinder chamber 37 and process hydraulic press 200.As long as motor 118 works as pump, then repeat this circulation.

Hydraulic press 200 of the present invention than the pump/engine design of traditional valve plate or pivot more effectively and quieter.In this hydraulic press, valve 202 and 204 all can cut out, so that cylinder chamber 37 can reduce pressure, energy is got back in the live axle 40.This kind effect improves efficient, and the high pressure drop metering is eliminated in this kind decompression and corresponding noise produces, and this noise is produced as valve plate or how much fixing metering hydraulic presses of pivot experience.

At another hydraulic press 300 shown in Figure 10, and this hydraulic mechanism causes and is similar to Fig. 2 and first hydraulic press shown in Figure 3.Same parts in two machines has been indicated identical reference character.Main difference is: the entrance and

exit safety check

33 and 34 that this hydraulic press uses the 3-position-3-way valve 302 of single motor hydraulic pressure to substitute in the aforementioned hydraulic machine.Exactly, cylinder block 301 has a plurality of holes 305, and extend from the longitudinal axis 25 that end face 303 is parallel to live axle 40 in these holes, and this helps to realize the compact structure of hydraulic press 300.Each hole in those holes 305 and first and second

annular passs

321 and 322 and cylinder 36 in a cylinder be communicated with.First annular pass 321 is opened in first port 324, and second annular pass 322 is opened in second port 326.Be provided for supplying with independent the 3rd port 328 of lubricating fluid.

The single control valve 302 of each cylinder 36 extends in the hole 305 that is associated and has spool 306; This spool 306 moves to diverse location through solenoid 308, operates this solenoid 308 by controller 122 in response to the signal that comes from drive axle position sensor 310.The spool 306 of power supply hydrovalve 302 is parallel to axis 25 orientations of live axle 40, to move along paralleling to the axis.Notice that in each cyclic process, the spool 306 of electro-hydraulic valve is between the outermost position of the head of drive axis 25 and piston 52.This kind location of valve 302 and the directed integral diameter that can further reduce hydraulic press 300.

First port 324 is connected in all control valves 302 that are used for cylinder chamber 37 by first annular pass 321, and second annular pass 322 is connected in all control valves with second port 326.In a position of spool 306, first annular pass 321 and thus first port 324 be communicated with cylinder chamber 37.In the second place of spool 306, second annular pass 322 and thus second port 326 be communicated with cylinder chamber 37 fluids.Spool 306 has central position or the 3rd position, in this position, cylinder chamber 37 from state that two

annular passs

321 and 322 all are communicated with close.At this, the effect of two

safety check

33 and 34 is also duplicated in first hydraulic press 14 in the operation of single 3-position-3-way valve 302, so that fluid is pumped to second port 326 along a direction from first port 324.The operation of this 3-position-3-way valve 302 can be reversed by controller, so that fluid is pumped to first port 324 from second port 326 in opposite direction, makes that thus hydraulic press 300 can be as the two-way pump effect.

Also can operate this 3-position-3-way valve 302 makes hydraulic press 300 work as motor.In this pattern, above effect for hydraulic press 200 described first and second valves 202 and 204 is duplicated in the position of spool 306.

Compared with using two position two-way valve, use need be in the controller less electronic driver of single 3-position-3-way valve 302 for each cylinder chamber for each cylinder chamber.This also has following effectively advantage: can stop that this piston-cylinder is to reduce pressure on input shaft.This kind structure is also supported hydraulic press optionally is used as variable delivery pump or motor, with according to application and controller indication, optionally pumps fluid into arbitrary port and receives the high-voltage oil liquid from arbitrary port as motor.

The description of front relates generally to a preferred embodiment of the present invention.Although the various alternative of paying close attention in the scope of the invention should reckon with, those of ordinary skill in the art will appreciate that present from the explanation of the embodiment of the invention and conspicuous other alternative that become.Therefore, scope of the present invention should be confirmed by appended claims, and should do not limited by top disclosure.

Claims

1. hydraulic press comprises:

Cylinder block, said cylinder block has first port, second port and outer surface, and has a plurality of cylinders, and said a plurality of cylinders radially are arranged in the said cylinder block and have the opening that passes said outer surface;

A plurality of piston assemblys, each piston assembly are received in different in the said a plurality of cylinder cylinders slidably;

A plurality of control valve units, each control valve unit is connected in said first and second ports with a cylinder in said a plurality of cylinders;

Live axle, said live axle rotatably are received in the said cylinder block and have eccentric cam, and in order in said a plurality of cylinders, to drive said a plurality of piston assemblys; And

Zonula occludens, said zonula occludens cooperates with said outer surface and the opening of said a plurality of cylinders is closed.

2. hydraulic press as claimed in claim 1 is characterized in that the outer surface of said cylinder block is circular, and said closed ring is circular.

3. hydraulic press as claimed in claim 1 is characterized in that said closed ring has smooth belt shape.

4. hydraulic press as claimed in claim 1 is characterized in that, also comprises plunger, and said plunger is inserted in each cylinder below said closed ring, and between the wall of said plunger and said cylinder, has O shape circle.

5. hydraulic press as claimed in claim 1; It is characterized in that; In said a plurality of piston assembly each comprises piston and piston rod, and wherein said piston rod comprises the bar that has curved plate, through said bar power is passed to said eccentric cam; And said curved plate has a surface, and said surface has the surface area greater than the maximum cross-section area of said bar.

6. hydraulic press as claimed in claim 5 is characterized in that, also comprises retaining ring, and said retaining ring cooperates around said live axle extension and with the curved plate of each piston rod, leaves said eccentric cam to prevent said curved plate motion.

7. hydraulic press as claimed in claim 5 is characterized in that, also comprises two retaining rings, and each retaining ring is extended around said live axle, and on the opposite side of said bar, cooperates with the curved plate of each piston rod.

8. hydraulic press as claimed in claim 5; It is characterized in that; Also comprise camshaft bearing; Said camshaft bearing extends and has outer race around said live axle, and a plurality of roller is between said outer race and said eccentric cam, and wherein the base plate of each piston rod has the surface that abuts in the outer race of said bearing.

9. hydraulic press as claimed in claim 1 is characterized in that said piston rod has an end, and said end has the spherical head of part, and said head cooperates with part bulb-shaped recess portion in the said piston.

10. hydraulic press as claimed in claim 9 is characterized in that said piston has internal cavities, and the said part spherical head of said piston rod is received in the said internal cavities.

11. hydraulic press as claimed in claim 10 is characterized in that, also comprises retainer, said retainer is positioned at said internal cavities, and keeps cooperating of said part spherical head and said piston.

12. hydraulic press as claimed in claim 10 is characterized in that, also comprises spring, said spring is positioned at said internal cavities, and the part spherical head of said piston rod is cooperated with groove in the said piston.

13. hydraulic press as claimed in claim 1 is characterized in that, said piston and piston rod form single-piece, and said piston has the spherical circumferential surface of the part that cooperates with the wall of said cylinder.

14. hydraulic press as claimed in claim 1 is characterized in that,

Said cylinder block comprises a plurality of first holes; Said a plurality of first hole is arranged in first end face and is parallel to the longitudinal axis extension of said live axle; And each in said a plurality of first hole is communicated with said first port and is opened among the cylinder in said a plurality of cylinder; And said cylinder block also comprises a plurality of second holes; The longitudinal axis that said a plurality of second hole is arranged in second end face and is parallel to said live axle extends, and in said a plurality of second hole each is communicated with said second port and is opened among the cylinder in said a plurality of cylinder; And

Said control valve unit comprises a plurality of first valves and a plurality of second valve, and each first valve is arranged in a hole in said first hole, and each second valve is arranged in a hole in said second hole.

15. hydraulic press as claimed in claim 14; It is characterized in that; Also comprise tubular sleeve; Said tubular sleeve is arranged in each cylinder of said a plurality of cylinders, and wherein each tubular sleeve partly extends through the opening among corresponding that cylinder in said first hole and said second hole.

16. hydraulic press as claimed in claim 14 is characterized in that, each valve in said first valve and said second valve all is the two-way valve of electric operation.

17. hydraulic press as claimed in claim 16 is characterized in that, each valve in said first valve and said second valve all is a two position two-way valve.

18. hydraulic press as claimed in claim 1 is characterized in that,

Said cylinder block comprises a plurality of holes, and the longitudinal axis that said hole is arranged in first end face and is parallel to said live axle extends, and in said a plurality of hole each is opened in the difference cylinder in said a plurality of cylinder; And

Said control valve unit comprises the valve of a plurality of electric operations, and each valve is arranged in a hole in said a plurality of holes, in order to the cylinder that is associated optionally is connected with said first and second ports.

19. fluid operating machine as claimed in claim 18 is characterized in that, each valve in the valve of said a plurality of electric operations is the 3-position-3-way valve.

20. hydraulic press as claimed in claim 1 is characterized in that, said live axle has passage, and said passage has opening in the surface of said eccentric cam, is used to transmit the fluid that is used to lubricate.

21. hydraulic press as claimed in claim 20 is characterized in that, the passage of said live axle is operably connected, since receive the fluid that gets into said hydraulic press through in said first port and said second port.

22. a hydraulic press comprises:

Zonula occludens, said zonula occludens cooperates with said outer surface and the opening of said a plurality of cylinders is closed;

Live axle, said live axle rotatably are received in the said cylinder block and have eccentric cam;

Camshaft bearing, said camshaft bearing extends around said live axle, and has outer race, and a plurality of roller is between said outer race and said eccentric cam;

A plurality of piston assemblys, each piston assembly are received in the difference cylinder in said a plurality of cylinder slidably, and comprise that piston and piston rod, wherein said piston rod comprise having the bar that abuts in the curved plate of said outer race;

Retaining ring, said retaining ring cooperates around said live axle extension and with the curved plate of each piston rod, so that said curved plate is held against in said outer race; And

A plurality of control valve units, each control valve unit optionally is connected in said first and second ports with a cylinder in said a plurality of cylinders.

23. hydraulic press as claimed in claim 22 is characterized in that, said piston rod has an end, and said end has the spherical head of part, and said head cooperates with part bulb-shaped recess portion in the said piston.

24. hydraulic press as claimed in claim 23 is characterized in that, also comprises retainer, said retainer keeps said part spherical head to cooperate with said piston.

25. hydraulic press as claimed in claim 23 is characterized in that, also comprises spring, said spring is biased to the part spherical head of said piston rod with said piston and cooperates.

26. hydraulic press as claimed in claim 22 is characterized in that, said piston and piston rod form single-piece, and said piston has the spherical circumferential surface of the part that cooperates with the wall of said cylinder.

27. hydraulic press as claimed in claim 22 is characterized in that, said control valve unit comprises: a plurality of first valves, and each first valve is connected in said first port with a cylinder in said a plurality of cylinders; And a plurality of second valves, each second valve is connected in said second port with a cylinder in said a plurality of cylinders.

28. hydraulic press as claimed in claim 27 is characterized in that, each valve in said a plurality of first valves and said a plurality of second valve is the two-way valve of electric operation.

29. hydraulic press as claimed in claim 22 is characterized in that, said control valve unit comprises the 3-position-3-way valve of a plurality of electric operations, and each valve optionally is connected in said first and second ports with a cylinder in said a plurality of cylinders.

30. a hydraulic press comprises:

Cylinder block; Said cylinder block has first port, second port, first end face and second end face, a plurality of first hole and a plurality of second hole; And comprise a plurality of cylinders; Between said first end face and said second end face, the side is arranged; Said a plurality of first hole is arranged in an end face of said first and second end faces, and said a plurality of second hole is arranged in an end face of said first and second end faces, and said a plurality of cylinders radially are arranged in the said cylinder block and have the opening that passes said side;

Live axle, said live axle have eccentric cam and rotatably are received in the said cylinder block, and an end face from said first and second end faces is outwards outstanding;

A plurality of piston assemblys, said a plurality of piston assemblys are received in different in the said a plurality of cylinder cylinders slidably;

A plurality of first valves, each first valve are arranged in one first hole in said first hole, and between the cylinder in said first port and said a plurality of cylinder fluid passage are provided optionally; And

A plurality of second valves, each second valve are arranged in one second hole in said second hole, and between the cylinder in said second port and said a plurality of cylinder fluid passage are provided optionally.

31. fluid operating machine as claimed in claim 30 is characterized in that, also comprises zonula occludens, said zonula occludens cooperates with said side and the opening of said a plurality of cylinders is closed.

32. fluid operating machine as claimed in claim 30 is characterized in that, each valve in said first valve and said second valve all is the passive type valve

33. fluid operating machine as claimed in claim 30 is characterized in that, each valve in said first valve and said second valve all is the valve of electric operation.

34. fluid operating machine as claimed in claim 30 is characterized in that, each valve in said first valve and said second valve all is the two position two-way valve of electric operation.

35. hydraulic press as claimed in claim 30; It is characterized in that; In said a plurality of piston assembly each comprises piston, piston rod and retaining ring, and wherein said piston rod has the bar that has curved plate, through said bar power is passed to said eccentric cam; And said retaining ring cooperates around said live axle extension and with the curved plate of each piston rod, leaves said eccentric cam to prevent said curved plate motion.

36. fluid operating machine as claimed in claim 30 is characterized in that, said side limits closed arc periphery; And each valve in said a plurality of first valve and said a plurality of second valve all is positioned at said closed arc periphery.

37. a hydraulic press comprises:

Cylinder block; Said cylinder block has first port, second port, end face, side and a plurality of cylinder; Said a plurality of cylinder radially is arranged in the said cylinder block and has the opening that passes said side; And said cylinder block also comprises a plurality of holes in said first end face, and each hole is communicated with a cylinder fluid in said first port, said second port and the said a plurality of cylinder;

Live axle, said live axle have eccentric cam and rotatably be received in the said cylinder block and from said cylinder block outwards to be given prominence to;

A plurality of piston assemblys, said a plurality of piston assemblys are received in different in the said a plurality of cylinder cylinders slidably; And

A plurality of control valve units, each control valve unit are arranged in a hole in said hole, and a cylinder in said a plurality of cylinders and the fluid between each port in said first and second ports flowed optionally control.

38. fluid operating machine as claimed in claim 37 is characterized in that, also comprises zonula occludens, said zonula occludens cooperates with said side and the opening of said a plurality of cylinders is closed.

39. fluid operating machine as claimed in claim 37 is characterized in that, each control valve unit in said a plurality of control valve units all is the three-way valve of electric operation.

40. fluid operating machine as claimed in claim 37 is characterized in that, each control valve unit in said a plurality of control valve units all is the 3-position-3-way valve.

41. fluid operating machine as claimed in claim 37 is characterized in that, each control valve unit in said a plurality of control valve units comprises:

A plurality of first valves, each first valve are arranged in a hole in said hole, and optionally control the fluid between the cylinder in said first port and the said a plurality of cylinder is mobile; And

A plurality of second valves, each second valve are arranged in one second hole in said second hole, and optionally control the fluid between the cylinder in said second port and the said a plurality of cylinder is mobile.

42. hydraulic press as claimed in claim 37; It is characterized in that; In said a plurality of piston assembly each comprises piston, piston rod and retaining ring, and wherein said piston rod has the bar that has curved plate, through said bar power is passed to said eccentric cam; And said retaining ring cooperates around said live axle extension and with the curved plate of each piston rod, leaves said eccentric cam to prevent said curved plate motion.