CN105804820B

CN105804820B - VVL camshaft structures

Info

Publication number: CN105804820B
Application number: CN201610152738.9A
Authority: CN
Inventors: 秦天
Original assignee: Individual
Current assignee: Individual
Priority date: 2016-03-17
Filing date: 2016-03-17
Publication date: 2018-07-13
Anticipated expiration: 2036-03-17
Also published as: CN105804820A

Abstract

The invention discloses a kind of VVL camshaft structures, especially a kind of VVL camshaft structures for automotive engine applications.The present invention provides one kind can generating impact during high speed operation state and tick-over state mutually switch to avoid engine; energy effective protection camshaft parts; machine components service life can be greatly prolonged; and significantly reduce mechanical processing difficulty; improve the VVL camshaft structures of yield rate; including mandrel and cam pack; the cam pack is set on mandrel; it further include edge cam; the edge cam is contacted with two end faces of cam pack, and radial cams structure is additionally provided on the edge cam.High speed operation smooth conversion may be implemented relative to mandrel movement come driving cam component using edge cam in the application, make high Lower speed cam in transfer process quickly, accurate and impact it is small, reduce damage of the high low speed conversion to machine components, the durability for improving VVL camshafts, extends service life.

Description

VVL camshaft structures

Technical field

The present invention relates to a kind of VVL camshaft structures, especially a kind of VVL camshaft knots for automotive engine applications Structure.

Background technology

The port timing mechanism of engine is responsible for providing fresh air necessary to gasoline combustion acting to cylinder, and will combustion Exhaust gas discharge after burning, from operation principle, the major function of port timing mechanism be opened according to certain time limit and The inlet and outlet door for closing each cylinder, to realize the whole process of cylinder ventilation supply.For there is no changeable air valve skill For the common engine of art, intake and exhaust opening/closing time and lift are fixed, and the port timing of engine cannot basis The rotating speed of engine and change, this changeless valve stroke is difficult the work in different rotating speeds operating mode with respect to engine It needs.Therefore in order to meet the job requirement of engine full working scope it is necessary to design changeable air valve, the power gauge of engine is promoted It is existing, make burning more efficiently.To solve foregoing problems, VVL technologies, that is, changeable air valve lift technology is come into being.VVL technologies can To match suitable valve stroke in engine different rotating speeds, different load so that engine makes in the slow-speed of revolution, Smaller load With smaller valve stroke, improves cold start-up and reduce oil consumption.Using larger valve stroke when high rotating speed, big load, reduce Valve throttling loses, and improves volumetric efficiency, improves power output of the engine in high rotating speed, big load and can reduce engine Fuel consumption, improve fuel economy, reduce HC, the discharge of NOx.

Lift range variable technology is to control engine respectively using the cam of two kinds of different molded line in the prior art Valve stroke in high speed operation state and tick-over state, such as patent document《Two-stage is adjustable variable gas distribution》Publication number The camshaft structure used in CN201220616883, the patented technology are cased with cam sleeve outside camshaft, camshaft with The spline connection of cam sleeve both ends, stop collar are sleeved on outside cam sleeve；Lower speed cam be fixedly connected with High speed cam and with it is convex Axle sleeve is connected as one, and oppositely oriented spiral grooves are arranged in the both ends of cam sleeve, and groove mandril is placed in spiral grooves, And it is controlled by electromagnetic actuator to switch Lower speed cam High speed cam.The above technology is using groove mandril and spiral grooves come real The switching of existing High speed cam and Lower speed cam, handoff procedure impact is larger, at the end of handoff procedure, speed and acceleration It is not zero, needs to block mandril by groove trough rim, and VVL camshaft structures belong to precise part, high processing costs, It is easily damaged in impact process.

Invention content

It, can be to avoid engine in high speed operation shape technical problem to be solved by the invention is to provide a kind of simple in structure State and tick-over state generate impact during mutually switching, energy effective protection camshaft parts can greatly prolong machine The VVL camshaft structures of tool part service life.

The present invention solves VVL camshaft structures used by its technical problem, including mandrel and cam pack, the cam Component is set on mandrel, is provided with location hole on the mandrel, and the cam pack includes high low speed cam set and axle journal, often The high low speed cam set of group is made of a High speed cam and a Lower speed cam, and two groups high low speed cam set matches, described Axle journal is located between the same fast cam set of a pair of of height, further includes locating slot, the locating slot is arranged in the both sides of cam pack, institute It states locating slot to be made of high speed locating slot and low speed locating slot, elastic component is provided in the location hole, the both ends of elastic component are set It is equipped with steel ball, when engine is in high speed operation state, the steel ball part at elastic component both ends is located in high speed locating slot, separately A part is located in location hole；When engine is in tick-over state, the steel ball part at elastic component both ends is located at low speed In locating slot, another part is located in location hole, further includes extremity piece, and the extremity piece is arranged in the both sides of cam pack.

Further, being additionally provided with radial cams on the extremity piece, the axial end face cam and radial cams are compound On extremity piece.

Further, the rate curve of the axial end face cam is by the initial segment, accelerating sections, high speed changeover portion, deceleration Section and ending segment are connected in sequence, and the speed at the end of axial end face cam lift and acceleration equal zero.

Further, the speed and acceleration at the end of the radial cams lift are zero.

Further, the cam pack includes two pairs high low speed cam set, between the two pairs high low speed cam set It is provided with spacer.

Further, further including intermediate pin, two axial end face cams for being located at the adjacent side of two groups of cam packs are logical It crosses and is driven with the intermediate pin that the axial end face cam of the side two contacts simultaneously.

Further, the intermediate pin is flat pin.

Further, the intermediate pin is elliptic pin.

Further, the intermediate pin is double-pin.

Further, further including the detection device for detecting intermediate pin radial position.

The beneficial effects of the invention are as follows：The application is moved come driving cam component relative to mandrel using edge cam, due to The shape of edge cam can according to cam pack move axially requirement be designed so that it can driving cam component according to Meet the small characteristics of motion of impact to axially move, therefore the application camshaft structure may be implemented high speed operation and steadily turn Change, make high Lower speed cam in transfer process quickly, accurate and impact it is small, significantly reduce high low speed conversion to machine components Damage, substantially increases the durability of VVL camshafts, extends its service life.

Description of the drawings

Fig. 1 is the lifting curve figure of edge cam；

Fig. 2 is the speed curve diagram of edge cam；

Fig. 3 is the acceleration plots of edge cam；

Fig. 4 is the lifting curve figure of radial cams；

Fig. 5 is the speed curve diagram of radial cams；

Fig. 6 is the acceleration plots of radial cams；

Fig. 7 is the structural schematic diagram that cam pack of the present invention is separate structure；

Fig. 8 is the structural schematic diagram that the present invention uses two one group of form of cylinder；

Parts, position and number in figure：Mandrel 1, axle journal 2, high low speed cam set 3, High speed cam 4, Lower speed cam 5, Location hole 6, high speed locating slot 8, low speed locating slot 9, steel ball 10, elastic component 11, extremity piece 12, spacer 14, the initial segment 15, accelerating sections 16, high speed changeover portion 17, braking section 18, ending segment 19.

Specific implementation mode

The invention will be further described below in conjunction with the accompanying drawings.

Embodiment 1：As shown in fig. 7, VVL camshaft structures in the present embodiment, including mandrel 1 and cam pack, it is convex Wheel assembly is set on mandrel 1, and location hole 6 is provided on the mandrel 1, and the cam pack includes high 3 He of low speed cam set Axle journal 2, every group high low speed cam set 3 are made of a High speed cam 4 and a Lower speed cam 5, and two groups high low speed cam set 3 is matched In a pair, the axle journal 2 is located between same a pair of of height speed cam set 3, further includes locating slot, the locating slot is arranged in cam The both sides of component, the locating slot are made of high speed locating slot 8 and low speed locating slot 9, and elastic component is provided in the location hole 6 11, elastic component 11 is provided at both ends with steel ball 10, when engine is in high speed operation state, the steel ball 10 at 11 both ends of elastic component A part is located in high speed locating slot 8, and another part is located in location hole 6；When engine is in tick-over state, elasticity 10 part of steel ball at 11 both ends of part is located in low speed locating slot 9, and another part is located in location hole 6, further includes extremity piece 12, institute Extremity piece 12 is stated to be arranged in the both sides of cam pack.When engine needs to convert between high speed operation state and tick-over state When, solenoid-driven push rod or pin enter the position with axial end face cam contact, and axial end face cam was rotating at this time Push rod pushes axial edge cam to move axially as requested in journey, and axial end face cam drives cam pack axially to move again It is dynamic, to realize the switching of high low speed working condition.It is determined by its lifting curve due to the shape of edge cam, and lifting curve Also it determines the movement law of cam pack, therefore the shape of edge cam can be designed according to the requirement that cam pack moves Shape.The application is conducive to cam pack after being driven using edge cam and is steadily moved in handoff procedure, and it is right to effectively prevent its Engine component causes to impact.

Embodiment 2：In the present embodiment, be additionally provided with radial cams on the extremity piece 12, the axial end face cam and Radial cams is compounded on extremity piece 12, and the radial cams on extremity piece 12, which is arranged, can make to be put down by the push rod or pin of solenoid-driven Steady disengaging extremity piece 12, the mode that powder metallurgy can be used in the extremity piece 12 of this example are manufactured.

Embodiment 3：Cam is further increased using the lifting curve of preferred axial end face cam in the present embodiment Stationarity when axis working condition switches.

As shown in Fig. 2, the rate curve of axial end face cam is by the initial segment 15, accelerating sections 16, high speed changeover portion 17, deceleration Section 18 and ending segment 19 are connected in sequence, and the speed at the end of axial end face cam lift and acceleration equal zero.Before Stating rate curve division can make cam pack first gently accelerate to certain speed, into adding in the initial segment 15 when lift starts Further accelerate the increased speed of speed after fast section 16, when speed advances into high speed changeover portion 17 close to peak value, in high speed mistake The speed that reducing speed changes in section 17 is crossed, makes cam pack speed by accelerating to deceleration smooth transition, when entrance braking section 18 The speed for accelerating speed reduction afterwards, enters ending segment 19, slows down speed in ending segment 19 after so that it is comparatively fast reduced to the speed of setting The speed reduced is spent, its speed is made steadily to be decreased to zero.Corresponding lifting curve and accelerating curve are as shown in figures 1 and 3.

As a further improvement, extremity piece 12, radial convex are more smoothly passed in and out in order to make push rod steadily pass in and out extremity piece 12 Speed and acceleration at the end of wheel lift are zero.Cam lifting curve shown in Fig. 4 may be used when specific implementation, therewith phase Corresponding rate curve and accelerating curve are as shown in Figure 5 and Figure 6.

Embodiment 4：As shown in figure 8, in the present embodiment, cam pack includes two pairs high low speed cam set 3, two pairs of height Spacer 14 is provided between fast cam set 3.Since a pair of high low speed cam set 3 corresponds to a cylinder of engine, the present embodiment will Two pairs high low speed cam set 3 is used as one group, and first two cylinders of corresponding engine form the form of one group of both one group of two cylinder therewith. Spacer 14 is set between two pairs high low speed cam set 3, thus eliminates 1 as shown in Figure 1 two pair of high Lower speed cam of embodiment Edge cam between group 3, while the solenoid valve at this and push rod are also saved, so that solenoid valve is reduced to original by original eight Four come.

Embodiment 5：Further include intermediate pin in the present embodiment, is located at two axial ends of the adjacent side of two groups of cam packs Face cam is driven by the intermediate pin contacted simultaneously with the axial end face cam of the side two.The present embodiment is on the basis of embodiment 4 On be further improved, be located at two groups of cam pack adjacents two axial end face cams use by the same solenoid-driven It sells to push, can reduce by a solenoid valve again in this way, as shown in figure 8, for the engine of four cylinders, VVL is convex Corresponding two groups of cam packs, i.e., four pairs high low speed cam set 3 on wheel shaft structure, if needing eight using the structure in embodiment 1 A solenoid valve, and the present embodiment only needs three solenoid valves.

Embodiment 6：Drive two axial end face cams in centre position simultaneously using flat pin in the present embodiment.Make The both ends of flat pin simultaneously with two axial end face cam contacts.

Embodiment:7：It uses the pin for elliptic pin in the present embodiment, carrys out while driving two axis in centre position To edge cam.

Embodiment 8：It realizes with a solenoid valve while driving two intermediate using the structure of double-pin in the present embodiment Axial end face cam.

Embodiment 9：The detection device for detecting intermediate pin radial position is increased in the present embodiment.The present embodiment is only Check intermediate pin radial position, it is not necessary to which the position for checking both sides pin is to judge intermediate pin by the detection set to intermediate pins position It is no to enter correctly into or exit extremity piece 12.

Claims

1.VVL camshaft structures, including mandrel (1) and cam pack, the cam pack are set on mandrel (1), feature It is：It is provided with location hole (6) on the mandrel (1), the cam pack includes high low speed cam set (3) and axle journal (2), often The high low speed cam set (3) of group is made of a High speed cam (4) and a Lower speed cam (5), and two groups high low speed cam set (3) is matched In a pair, the axle journal (2) is located between the same fast cam set (3) of a pair of of height, further includes locating slot, and the locating slot setting exists The both sides of cam pack, the locating slot are made of high speed locating slot (8) and low speed locating slot (9), are set in the location hole (6) It is equipped with elastic component (11), elastic component (11) is provided at both ends with steel ball (10), when engine is in high speed operation state, elasticity Steel ball (10) part at part (11) both ends is located in high speed locating slot (8), and another part is located in location hole (6)；When starting When machine is in tick-over state, steel ball (10) part at elastic component (11) both ends is located in low speed locating slot (9), another portion Divide and be located in location hole (6), further includes extremity piece (12), the extremity piece (12) is arranged in the both sides of cam pack, the extremity piece (12) axial end face cam is provided on, the rate curve of the axial end face cam is by the initial segment (15), accelerating sections (16), height Fast changeover portion (17), braking section (18) and ending segment (19) are connected in sequence, and the speed at the end of axial end face cam lift Degree and acceleration are zero.

2. VVL camshaft structures as described in claim 1, it is characterised in that：It is additionally provided with radial convex on the extremity piece (12) Wheel, the axial end face cam and radial cams are compounded on extremity piece (12).

3. VVL camshaft structures as claimed in claim 2, it is characterised in that：Speed at the end of the radial cams lift It is zero with acceleration.

4. VVL camshaft structures as described in claim 1, it is characterised in that：The cam pack includes that two pairs of high low speed are convex Wheel group (3) is provided with spacer (14) between the two pairs high low speed cam set (3).

5. VVL camshaft structures as claimed in claim 4, it is characterised in that：Further include intermediate pin, is located at two groups of cam packs Two axial end face cams of adjacent side are driven by the intermediate pin contacted simultaneously with the axial end face cam of the side two.

6. VVL camshaft structures as claimed in claim 5, it is characterised in that：The intermediate pin is flat pin.

7. VVL camshaft structures as claimed in claim 5, it is characterised in that：The intermediate pin is elliptic pin.

8. VVL camshaft structures as claimed in claim 5, it is characterised in that：The intermediate pin is double-pin.

9. VVL camshaft structures as claimed in claim 5, it is characterised in that：Further include for detecting intermediate pin radial position Detection device.