CN113482742A

CN113482742A - Valve driving device of engine and driving method thereof

Info

Publication number: CN113482742A
Application number: CN202110226473.3A
Authority: CN
Inventors: 褚平华; 孙煜
Original assignee: Individual
Current assignee: Individual
Priority date: 2021-03-01
Filing date: 2021-03-01
Publication date: 2021-10-08

Abstract

The invention relates to a valve driving device of an engine and a driving method thereof, which comprises a box body, an upper connecting rod, a lower connecting rod, a braking piston and a elephant foot component, wherein a vertical channel and a horizontal channel which are communicated are arranged in the box body, the lower part of the vertical channel is provided with the upper connecting rod, the lower connecting rod and the braking piston, the elephant foot component is arranged in the horizontal channel, revolute pairs are respectively arranged among the box body, the upper connecting rod, one side ball of a ball pin of the elephant foot component, the lower connecting rod and the braking piston, an engine oil path is arranged in the box body to communicate the horizontal channel with the engine oil path, the elephant foot component is controlled by opening and closing the engine oil path, and the positions of the upper connecting rod and the lower connecting rod are adjusted to enable the upper connecting rod and the lower connecting rod to be vertical or inclined, so as to realize the extension and retraction of the braking piston. The invention adopts the elephant foot component, reduces parts and simplifies the structure; a mechanical link structure is adopted, so that the reaction time is shortened, and the processing precision is reduced; the valve drive is not affected by the temperature and pressure of the engine oil; the valve driving design is flexible, the distance between the engine piston and the air valve rod can be reduced, and the valve driving device can be integrated with a rocker arm of an engine valve mechanism.

Description

Valve driving device of engine and driving method thereof

The technical field is as follows:

the invention relates to the field of machinery, in particular to an engine brake, and particularly relates to a valve driving device of the engine brake and a driving method thereof.

Background art:

the commercial vehicle for long-distance transportation needs to use braking frequently when running on a long gentle slope road, and the commercial vehicle without the auxiliary braking device needs to use the wheel type braking of a foot brake continuously to reduce the speed of the vehicle. However, on a long gentle slope road, the temperature of the brake pad is raised too fast due to long-term use of the wheel brake, so that the temperature of the brake pad is too high, the braking effect is likely to be reduced, even the brake pad is failed, and serious irreparable personal and property loss is easily caused, which is one of important reasons that serious traffic accidents often occur on mountainous roads with complex terrain, so that an auxiliary brake device is necessary for a commercial vehicle.

In the field of vehicle auxiliary braking, there are three different retarding devices, namely a hydraulic retarder, an eddy current retarder and an engine brake (also called an engine retarder). The hydraulic retarder and the eddy current retarder are large in size and weight, are not beneficial to realizing the light weight of an automobile, and are expensive; the two retarders are only largely used on the passenger car. The engine brake has the advantages of low cost, light weight, low working power consumption and no oil consumption; the performance is good, and the device is reliable and durable (can not generate heat like a hydraulic retarder or catch fire like an eddy current retarder) and is suitable for the Chinese market. Compared with a truck without the engine brake, the truck with the engine brake can effectively reduce the braking times of a long downhill road section, so that the replacement frequency of the brake pads and the tires is reduced, and the maintenance cost of the truck is further reduced.

Engine brakes are known in the art that use the valve train of an internal combustion engine as the braking means, and only the engine needs to be temporarily converted to a compressor. This transition shuts off fuel, opens the exhaust valve at or near the end of the compression stroke of the engine piston, allowing the compressed gas (air for braking) to be released, and the energy absorbed by the compressed gas during the compression stroke of the engine cannot return to the engine piston during the subsequent expansion stroke, but is dissipated through the exhaust and heat dissipation system of the engine. The net result is effective engine braking, slowing the vehicle.

In recent years, with the rapid development of commercial vehicles, engine braking has also been increasingly used in practice. However, most of the existing engine braking technologies adopt a hydraulic engine brake: the opening and closing of the brake exhaust valve are controlled by a set of hydraulic control device by utilizing the incompressibility 'jack' principle of engine oil. However, the hydraulic system has many parts, high requirement on machining precision, complex control system and high influence of the cleanliness of the engine oil, so the reliability is low and the failure rate is high. Meanwhile, under the low-speed working condition of the engine, the actual braking valve opening lift is reduced relative to the theoretical design lift under the influence of lower engine oil pressure, and the braking power value under the low-speed working condition is reduced, so that the use effect of the whole vehicle on engine braking is influenced finally.

Furthermore, the above-mentioned hydraulically actuated engine brakes have another drawback, namely the retractability or deformation of the hydraulic system, which is related to the flexibility of the liquid, which high flexibility results in a large compression reduction of the brake valve lift, which reduction of the valve lift results in an increase of the valve load, which increase of the valve load results in a higher flexibility, resulting in a vicious circle. Further, the decrease in valve lift caused by hydraulic deformation increases with an increase in engine speed, as opposed to the tendency of brake valve lift required for engine braking performance. To reduce hydraulic flexibility, large diameter hydraulic pistons must be used, adding bulk and weight. And the oil flow takes a long time to extend or retract the large diameter piston, resulting in a brake system with large inertia and slow response.

The engine braking technology of [00xx ] commercial vehicles also adopts a mechanical brake, and a patent CN201910763362.9 provides a scheme of a mechanical valve driving mechanism, wherein the valve driving mechanism consists of a box body, a connecting rod, a starting piston and a driving piston. The box body is internally provided with a starting piston hole and a driving piston hole which are vertically crossed, a starting piston is arranged in the starting piston hole, a driving piston is arranged in the driving piston hole, and the connecting rod comprises a first connecting rod and a second connecting rod. A fluid passage is provided in the housing connecting the starting piston bore to an oil fluid network of the engine, oil pressure acts on the starting piston in the starting piston bore, and the starting piston urges the first and second connecting rods from a closed position to an open position along the guide slot in the housing. Further, the valve-driving mechanism includes a return mechanism that urges the first link and the second link from the open position to the closed position along the guide groove in the case. The return mechanism comprises a return spring and a return steel ball. The mechanical valve driving mechanism is adopted in the patent, the problem of a part of hydraulic engine brake is solved, but the starting and closing are still complicated by adopting a plurality of parts such as a starting piston and a return mechanism, and the return mechanism is composed of a return spring and a return steel ball and has the risk of unreliable connection.

The invention content is as follows:

the invention aims to provide a mechanical engine valve driving device, which aims to solve the technical problems of the prior art that a hydraulic driving engine brake system has defects, such as deformation, large inertia, slow reaction and the like; and the risk of complicated construction and unreliable connections in existing mechanical valve actuation schemes.

The valve driving device comprises a box body, an upper connecting rod, a lower connecting rod, a braking piston and a elephant foot component, wherein a vertical channel and a horizontal channel are arranged in the box body, the vertical channel is communicated with the horizontal channel, the upper connecting rod and the lower connecting rod are arranged in the vertical channel, and the braking piston is arranged at the lower part of the vertical channel; the horizontal channel is internally provided with a elephant foot component. The elephant foot component comprises an elephant foot and a ball pin, wherein a ball socket is arranged on the elephant foot and used for fixing the ball pin, the fixed ball pin plays a role in containing and limiting the ball pin, balls are arranged on two sides of the ball pin, one side of the ball pin is limited and fixed in the ball socket, and the other side of the ball pin is limited and connected with an upper connecting rod and a lower connecting rod through a contact surface of the ball.

Furthermore, the elephant foot structure can realize the push-pull action of the ball pin through the elephant foot and can also realize the height adjustment of the center of one side of the ball body of the ball pin of the elephant foot assembly.

Furthermore, the lower end of the upper connecting rod and a ball body on one side of the ball pin of the elephant foot component form a revolute pair, and the upper end of the lower connecting rod and a ball body on one side of the ball pin of the elephant foot component form a revolute pair. A rotating pair is arranged between the upper end of the upper connecting rod and the box body, and a rotating pair is arranged between the lower end of the lower connecting rod and the brake piston.

Further, an engine oil path is arranged in the box body and communicated with the horizontal channel, and the engine oil path connects the horizontal channel with an engine oil path network of the engine. The oil circuit network provides oil pressure, the oil pressure acts on the elephant foot of the elephant foot component in the horizontal channel to control the elephant foot of the elephant foot component to move, and the ball pin of the elephant foot component is driven to push the upper connecting rod and the lower connecting rod in the box body to the vertical position (the opening position) from the inclined position (the closing position). The oil circuit network of the engine oil does not provide the pressure of the engine oil, and the return spring controls the elephant foot of the elephant foot component to return, so that the ball pin of the elephant foot component is driven to push the upper connecting rod and the lower connecting rod in the box body to the inclined position (closing position) from the vertical position (opening position).

Furthermore, a return spring is arranged on the elephant foot component, one end of the return spring is fixed on the elephant foot component, and the other end of the return spring is fixed in the horizontal channel.

Furthermore, a spring seat is arranged at the lower part of the box body, a compression spring is fixed on the spring seat, and the upper end of the compression spring is connected to the brake piston.

Furthermore, a limiting block is arranged in the horizontal channel, a limiting groove is formed in the limiting block, the upper connecting rod, the lower connecting rod and the ball pin of the elephant foot component are located in the limiting groove, and the width of the limiting groove is slightly larger than that of the upper connecting rod, the lower connecting rod and the ball pin of the elephant foot component. The upper connecting rod and the lower connecting rod do plane motion along the limiting groove between a closing position and an opening position, an included angle is formed between the upper connecting rod and the lower connecting rod at the closing position, and the lower end face of the brake piston retracts; in the open position, the upper and lower connecting rods are positioned on a vertical coaxial line, with the lower end face of the brake piston extending out.

Furthermore, a positioning edge is arranged on the limiting block, and the positioning edge can prevent the upper connecting rod and the lower connecting rod from slipping.

Furthermore, a positioning edge is arranged on the ball pin of the foot-like component, and the positioning edge can prevent the upper connecting rod and the lower connecting rod from slipping off.

Furthermore, a valve clearance adjusting screw is arranged on the box body, and the bottom surface of the valve clearance adjusting screw is matched with the upper end of the upper connecting rod to form a rotating pair.

Furthermore, the box body is provided with a drain hole which communicates the vertical channel with the outside.

Further, the box body is a rocker arm or a valve bridge of an engine valve mechanism.

When the engine valve driving device needs to work, a control mechanism for driving the engine valve is opened to provide engine oil, the engine oil passes through an engine oil path network of the engine and provides engine oil pressure to a horizontal channel through an engine oil path in a box body, the engine oil pressure acts on an elephant foot of an elephant foot assembly, the elephant foot pushes a ball body on one side of a ball pin, the movement is transmitted through the ball pin, the ball body on the other side of the ball pin pushes an upper connecting rod and a lower connecting rod and pushes the upper connecting rod and the lower connecting rod from a closed position to an open position along a limiting groove, namely from an inclined included angle position to a vertical coaxial position, a brake piston connected with the bottom of the lower connecting rod generates height change and changes from a retracted position to an extended position, the bottom surface of the brake piston is close to the engine valve below, and the valve driving device is switched from a non-working position to a working position; the motion of the engine cam is transmitted to the engine valve through the rocker arm and a valve driving device at a working position in the rocker arm to generate the required valve motion;

when the engine valve driving device is not needed to work, the engine brake control mechanism is closed to unload the engine oil, the elephant foot of the elephant foot component is not pressed by the engine oil and is reset under the action of the reset spring, the elephant foot of the elephant foot component stops at the bottom surface of the horizontal channel, the elephant foot drives a ball body on one side of the ball pin, the movement is transmitted through the ball pin, and the ball body on the other side of the ball pin drives the upper connecting rod and the lower connecting rod. The upper connecting rod and the lower connecting rod are changed from the opening position to the closing position, namely from the vertical coaxial position to the inclined included angle position, the braking piston connected with the bottom of the lower connecting rod generates height change and is changed from the extending position to the retracting position, the bottom surface of the braking piston is separated from the engine valve below to generate a certain distance, and the valve driving device is switched from the working position to the non-working position; so that the motion of the engine cam is skipped and cannot be transmitted to the engine valve without generating valve motion.

Compared with the prior art, the invention has positive and obvious effect. In the invention, the elephant foot component realizes the inclination and the verticality of the upper connecting rod and the lower connecting rod, thereby realizing the closing and the opening of the valve mechanism; the height of the motion center of the inclined position and the vertical position, namely the height adjustment of the center of a ball body on one side of the ball pin of the foot-like component is satisfied. The elephant foot component is a flexible and reliable mechanical structure, and the elephant foot component is adopted, so that the double functions of pushing and pulling in the horizontal direction are realized, and the height adjustment in the vertical direction is also met; the number of parts is reduced, the structure is simplified, and the reliability of the valve driving device is improved. In application, the invention can be integrated with a rocker arm or a valve bridge of an engine valve mechanism, and the height, the volume and the weight of the engine are not influenced basically. A hydraulic bearing structure is not adopted, and the reaction time is reduced due to no liquid compression; a hydraulic control valve is not needed, so that the machining precision is reduced, and the machining cost is saved; liquid bearing is not adopted, leakage, deformation and load fluctuation caused by high oil pressure and high oil temperature are avoided, and valve driving is not influenced by the temperature and the pressure of engine oil; the valve driving design is flexible, and the distance between the engine piston and the air valve rod can be reduced.

Drawings

Fig. 1 is a schematic view of a housing of an engine valve-driving apparatus of the present invention.

Fig. 2 is a schematic view of embodiment 1 of the engine valve-driving apparatus of the present invention in the closed position.

Fig. 3 is a schematic view of embodiment 1 of the engine valve-driving apparatus of the present invention in an open position.

Fig. 4 is a left side view of a stopper in embodiment 1 of the engine valve-driving apparatus of the invention.

Fig. 5 is a front view of a stopper in embodiment 1 of the engine valve-driving apparatus of the invention.

Fig. 6 is a plan view of a stopper block in embodiment 1 of the engine valve-driving apparatus of the invention.

Fig. 7 is a front view of the elephant foot assembly in embodiment 1 of the engine valve driving apparatus of the present invention.

Fig. 8 is a front view of the elephant foot assembly of the engine valve actuation device of the present invention.

Fig. 9 is a front view of the ball pin of the elephant foot assembly in embodiment 1 of the engine valve actuating device of the present invention.

Fig. 10 is a schematic diagram showing the change in the center position of one-side spherical body of the ball pin of the foot-like assembly when embodiment 1 of the engine valve-driving apparatus of the invention is in the closed position and in the open position.

Fig. 11 is a schematic view of embodiment 2 of the engine valve-driving apparatus of the invention in the closed position.

Fig. 12 is a schematic view of embodiment 2 of the engine valve-driving apparatus of the invention in the open position.

Fig. 13 is a left side view of a stopper block in embodiment 2 of the engine valve-driving apparatus of the invention.

Fig. 14 is a front view of a stopper in embodiment 2 of the engine valve-driving apparatus of the invention.

Fig. 15 is a plan view of a stopper block in embodiment 2 of the engine valve-driving apparatus of the invention.

Fig. 16 is a front view of the elephant foot assembly in embodiment 2 of the engine valve driving apparatus of the present invention.

Fig. 17 is a front view of the ball pin of the elephant foot assembly in embodiment 2 of the engine valve actuating device of the present invention.

Detailed Description

Example 1:

as shown in fig. 1, 2 and 3, the engine valve actuation device 105 of the present invention includes a housing 100 (the housing shown in fig. 1 is a rocker arm that fits through a rocker arm aperture 150 on a rocker shaft (not shown) of the engine), upper and lower connecting

rods

310 and 320, a brake piston 330 and a elephant foot assembly 280. A vertical channel 140 and a horizontal channel 130 are provided in the housing 100, which intersect vertically. An upper connecting rod 310 and a lower connecting rod 320 are provided in the vertical passage, and a brake piston 330 is provided at the lower end of the vertical passage 140. The horizontal channel 130 is provided with a elephant foot assembly 280, a return spring 240 and a stop block 210.

As shown in fig. 7, 8 and 9, the elephant foot assembly 280 is composed of the elephant foot 250 and the ball pin 220, the elephant foot 250 is provided with a ball socket, both sides of the ball pin 220 are provided with balls, one side ball 260 and the other side ball 270, one side ball 260 of the ball pin 220 is fixed with the ball socket of the elephant foot 250, the mouth of the ball socket of the elephant foot 250 is provided with a closing structure, the size of the ball socket is reduced, and the ball pin 220 cannot be pulled out of the elephant foot 250; the other side of the ball 270 of the ball pin 220 connects the upper link 310 and the lower link 320. The elephant foot assembly 280 is a reliable mechanical structure that can perform the dual function of pushing and pulling the ball pin 220-when the elephant foot 280 pushes the ball pin 220, the bottom 421 of the socket of the elephant foot 250 pushes the top 424 of the ball 260 on one side of the ball pin; when the elephant foot 280 pulls the ball pin 220, the mouth 420 of the socket of the elephant foot 250 pulls the waist 423 of one side ball 260 of the ball pin; and a height change of the center of the other side sphere 270 of the ball pin 220 is achieved-since the mouth of the socket like the foot 250 is larger in size than the connection portion of the ball pin 220, the other side sphere 270 of the ball pin 220 can be rotated with the center of the one side sphere 260 fixed in the socket like the foot 250 as a rotation center.

As shown in fig. 4, 5 and 6, the stopper 210 is assembled in the horizontal channel 130, and the case 100 is provided with an assembly step 160 for limiting the installation position of the stopper 210; the limiting block 210 is provided with parallel edges 510 which are matched with a positioning structure (not shown) on the box body, so that the installation angle of the limiting block 210 can be limited; the set bolt 200 fixes the stopper 210 to the case 100. The limiting block 210 is provided with a limiting groove 520 (see fig. 6), the upper connecting rod 310, the lower connecting rod 320 and the part of the other side sphere 270 of the ball pin 220 of the elephant foot component 280 are positioned in the limiting groove 520, and the width of the limiting groove 520 is equal to or slightly larger than the outer diameter of the other side sphere 270 of the ball pin 220 of the upper connecting rod 310, the lower connecting rod 320 and the elephant foot component 280. The upper and

lower links

310, 320 move in a plane along the restraint slot 520 between a "closed" position (fig. 2) and an "open" position (fig. 3). In addition, the stopper 210 has a positioning edge 530.

A first revolute pair 430 is provided between the upper end surface of the upper link 310 and the case 100 (see fig. 2, which shows the adjustment screw 210 fixed to the case 100), the lower end surface of the upper link 310 and the upper end surface of the other side ball 270 of the ball pin 220 of the elephant foot assembly 280 are connected through a second revolute pair 431, the lower end surface of the other side ball 270 of the ball pin 220 of the elephant foot assembly 280 and the upper end surface of the lower link 320 are connected through a third revolute pair 432, a fourth revolute pair 433 is provided between the lower end surface of the lower link 320 and the upper end surface of the brake piston 330, and the lower end surface (bottom surface) 434 of the brake piston 330 is positioned above an engine valve (not shown). The four first revolute pairs 430, the second revolute pair 431, the third revolute pair 432 and the fourth revolute pair 433 of the embodiment are all spherical revolute pairs (a sphere is matched with a ball socket).

The adjusting bolt 300 installed on the case 100 is used to adjust the upper and lower initial positions (valve play) of the brake piston 330 in the vertical channel 140 (see fig. 2). For situations where the initial position of the brake piston 330 does not need to be adjusted, the adjustment bolt 300 is not needed. At this time, a revolute pair is formed between the upper end surface of the upper link 310 and the casing 100.

The lower portion of the case 100 has a spring seat 350, the spring seat 350 is fixed to the case 100, and the spring seat 350 is fixed to the case 100 using a fastening bolt 360 (see fig. 2). The spring seat 350 is used to support and fix the compression spring 340, the lower end of the compression spring 340 is fixed to the spring seat 350, and the upper end of the compression spring 340 is connected to the brake piston 330.

In the "closed" position (fig. 2), the upper and

lower links

310, 320 are centered on the other side of the ball 270 of the ball pin 220 of the elephant foot assembly 280, with the upper and

lower links

310, 320 forming an inclined angle (fig. 2); at the same time, the compression spring 340 acts on the brake piston 330, creating an upward force on the fourth revolute pair 433 that is transmitted to the third revolute pair 432, the second

revolute pair

431, and 430. Since the ball 260 on one side of the ball pin 220 of the elephant foot assembly 280 is fixed on the elephant foot 250, the friction force among the 4 revolute pairs, the first revolute pair 430, the second revolute pair 431, the third revolute pair 432 and the fourth revolute pair 433 can limit the mutual movement of the upper link 310, the ball 270 on the other side of the ball pin 220 of the elephant foot assembly 280 and the lower link 320, and the fact that the upper link 310 and the lower link 320 are kept in the inclined angle position in the 'closed' position is achieved.

In the "open" position (FIG. 3), the upper and

lower links

310, 320 contact the other side ball 270 of the ball pin 220 of the elephant foot assembly 280 and the locating edge 530 of the stop block 210; at the same time, the reaction force of the compression spring 340 and the engine valve acts on the brake piston 330, creating an upward force on the fourth revolute pair 433 that is transmitted to the third revolute pair 432, the second

revolute pair

431, and 430. The four first revolute pair 430, the second revolute pair 431, the third revolute pair 432 and the fourth revolute pair 433 are spherical revolute pairs, and besides the positioning function of the positioning edge 530, the spherical revolute pairs have a self-centering and self-stabilizing function, so that the centers of the upper connecting rod 310, the lower connecting rod 320 and the other side spherical body 270 of the ball pin 220 of the elephant foot assembly 280 can be ensured to be positioned on the same vertical axis (see fig. 3).

In the "closed" position (fig. 2), the return spring 240 urges the elephant foot 250 of the elephant foot assembly 280 against the bottom surface 120 (see fig. 1) of the horizontal channel 130, the elephant foot 250 carrying one side ball 260 of the ball pin 220, the motion being transmitted through the ball pin 220, the other side ball 270 of the ball pin 220 carrying the upper link 310 and the lower link 320, the upper link 310 and the lower link 320 forming an inclined angle (fig. 2). The compression spring 340 moves the brake piston 330 upward with its bottom (lower end) surface 434 spaced from the engine valve (not shown).

In the "open" position (fig. 3), i.e., when the valve-drive unit 105 needs to be actuated, the oil fluid network (not shown) of the engine supplies oil pressure to the horizontal passage 130 through the oil passage 110 provided in the housing 100 (see fig. 1), the oil pressure acts on the elephant foot 250 of the elephant foot assembly 280, the elephant foot 250 pushes one side ball 260 of the ball pin 220, the motion is transmitted through the ball pin 220, and the other side ball 270 of the ball pin 220 pushes the upper link 310 and the lower link 320, against the force of the return spring 240 and the compression spring 340, to push the upper link 310 and the lower link 320 from the "closed" position (fig. 2) to the "open" position (see fig. 3) along the retainer groove 520. In the "open" position (fig. 3), the upper link 310 and the lower link 320 are positioned on a vertical axis. The brake piston 330 moves downward with its bottom surface (lower end surface) 434 in proximity to the engine valve (not shown).

Switching from the "open" position (fig. 3) to the "closed" position (fig. 2), the upper and

lower links

310, 320 switch from a vertical coaxial position to a tilted pinching position, with the center of the other side sphere 270 of the ball pin 220 of the elephant foot assembly 280 having a distance variation 630 in the horizontal direction and a height variation 610 in the vertical direction (see fig. 10). The change 630 in the distance of the center of the sphere 270 in the horizontal direction on the other side of the ball pin 220 of the elephant foot assembly 280 is achieved by the movement of the elephant foot 250 of the elephant foot assembly 280, which moves the ball pin 220; the change in height 610 in the vertical direction of the center of the ball 270 on the other side of the ball pin 220 of the elephant foot assembly 280 is accomplished by the rotation of the ball 260 on one side of the ball pin 220 in the socket of the elephant foot 250. The elephant foot assembly 280 enables not only a push-pull action of bi-directional movement of the center of the other side ball 270 of the ball pin 220 in the horizontal direction but also a height adjustment of the center of the other side ball 270 of the ball pin 220.

Likewise, switching from the "closed" position (fig. 2) to the "open" position (fig. 3), the upper link 310 and the lower link 320 switch from the vertical coaxial position to the angled pinch position, with the center of the ball on one side of the ball pin 220 of the elephant foot assembly 280 varying in distance 630 horizontally and also varying in height 610 vertically, with the elephant foot assembly 280 being able to achieve both the horizontal distance variation 630 and the vertical height variation 610.

The working procedure of example 1 is:

when the engine valve driving device 105 is required to operate, the engine valve driving control mechanism (not shown) is opened to supply oil, the oil is supplied to the horizontal channel 130 through an oil path network (not shown) of the engine via an oil path 110 in the box 100 (see fig. 1), the oil pressure acts on the elephant foot 250 of the elephant foot assembly 280, the elephant foot 250 pushes one side ball 260 of the ball pin 220, the motion is transmitted through the ball pin 220, the other side ball 270 of the ball pin 220 pushes the upper connecting rod 310 and the lower connecting rod 320 to be pushed from the closed position (fig. 2, inclined angle position) to the open position (fig. 3, vertical coaxial position) along the limiting groove 520, the brake piston 330 connected with the bottom of the lower connecting rod 320 generates a height change 620 (see fig. 10) to be changed from the retracted position to the extended position, and the bottom surface (lower end surface) 434 thereof is close to (connected with) the engine valve below, the valve-driving apparatus 105 is switched from the non-operating position to the operating position. At this point, motion of an engine cam (not shown) is transferred to the engine valve via the rocker arm and the valve actuation device 105 in the operating position within the rocker arm to produce a desired valve motion, such as for engine braking.

When the engine valve driving device 105 is not needed to work, the engine brake control mechanism is closed to discharge oil, the elephant foot 250 of the elephant foot assembly 280 is not subjected to oil pressure and is reset under the action of the reset spring 240, the elephant foot 250 of the elephant foot assembly 280 is stopped on the bottom surface 120 of the horizontal channel 130, the elephant foot 250 drives the ball 260 on one side of the ball pin 220, the motion is transmitted through the ball pin 220, and the ball 270 on the other side of the ball pin 220 drives the upper connecting rod 310 and the lower connecting rod 320. The upper and

lower links

310 and 320 change from the "open" position (fig. 3, vertical coaxial position) back to the "closed" position (fig. 2, angled position), the brake piston 330 attached to the bottom of the lower link 320 undergoes a height change 620 (see fig. 10) from an extended position to a retracted position with its bottom surface (lower face) 434 spaced from the underlying engine valve creating a gap, and the valve actuation device 105 switches from the operating position to the inoperative position such that the motion of the engine cam (not shown) is skipped and not transmitted to the engine valve without valve motion.

Example 2:

as shown in fig. 11 and 12, the engine valve-driving apparatus 105 of the present embodiment is a modification of embodiment 1, and includes a case 100 (the case shown in fig. 1 is a rocker arm, which is fitted to a rocker shaft (not shown) of the engine through a rocker arm hole 150), upper and lower connecting

rods

310 and 320, a brake piston 330, and a elephant foot assembly 290. Wherein the housing 100, the upper link 310, the lower link 320, and the brake piston 330 are unchanged, but the elephant foot assembly 290 is changed. Similarly, a vertical channel 140 and a horizontal channel 130 are provided in the housing 100, which intersect vertically. An upper connecting rod 310 and a lower connecting rod 320 are provided in the vertical passage, and a brake piston 330 is provided at the lower end of the vertical passage 140. The horizontal channel 130 is provided with a elephant foot assembly 290, a return spring 240 and a stop block 215, wherein the stop block 215 is modified.

The elephant foot assembly 290 consists of the elephant foot 250 and the ball pin 225 (see fig. 16, 8 and 17), the elephant foot 250 is provided with a ball socket, both sides of the ball pin 225 are provided with balls 265 and 275, one side of the ball pin 225 is fixed with the ball socket of the elephant foot 250, the mouth of the ball socket of the elephant foot 250 is provided with a closing structure, the size of the ball socket is reduced, and the ball pin 225 cannot be pulled out of the elephant foot 250; one side ball 275 of the ball pin 225 connects the upper link 310 and the lower link 320. Wherein the ball pin 225 is modified, and a

positioning edge

425 and 427 and a limiting edge 426 are arranged at one side of the ball pin 225 at the ball position. The stop block 215 has a positioning edge 530 and an additional depending edge 540 (see fig. 13, 14 and 15). The elephant foot assembly 290 is a reliable mechanical structure that performs the dual function of pushing and pulling the ball pin 225 — as the elephant foot 290 pushes the ball pin 225, the bottom 421 of the socket of the elephant foot 250 pushes the top 429 of one side ball 265 of the ball pin; when the elephant foot 290 pulls the ball pin 225, the mouth 420 of the socket like foot 250 pulls the waist 428 of one side ball 265 of the ball pin; and effecting a height change of the center of the one-side ball 275 of the ball pin 225-since the mouth of the socket 250 like the foot 290 is larger in size than the connecting portion of the ball pin 225, the one-side ball 275 of the ball pin 225 can rotate with the center of the one-side ball 265 fixed in the socket like the foot 250 (see fig. 16, 8 and 17).

A first revolute pair 430 is provided between the upper end surface of the upper link 310 and the case 100 (here, the adjusting screw 210 fixed to the case 100 is shown), the lower end surface of the upper link 310 and the upper end surface of one side ball 275 of the ball pin 225 of the elephant foot assembly 290 are connected through a second revolute pair 431, the lower end surface of one side ball 275 of the ball pin 225 of the elephant foot assembly 290 and the upper end surface of the lower link 320 are connected through a third revolute pair 432, a fourth revolute pair 433 is provided between the lower end surface of the lower link 320 and the upper end surface of the brake piston 330, and the lower end surface (bottom surface) 434 of the brake piston 330 is positioned above an engine valve (not shown). The four revolute pairs illustrated in the present embodiment, the first revolute pair 430, the second revolute pair 431, the third revolute pair 432 and the fourth revolute pair 433 are all spherical revolute pairs (a sphere is matched with a ball socket).

In the "open" position (FIG. 12), upper link 310, lower link 320 and positioning edge 530 of stop block 215 are in contact with positioning edge 427 of ball pin 225 of elephant foot assembly 290 while depending edge 426 of ball pin 225 and depending edge 540 of stop block of elephant foot assembly 290 are in close proximity; at the same time, the reaction force of the compression spring 340 and the engine valve acts on the brake piston 330, creating an upward force on the fourth revolute pair 433 that is transmitted to the third revolute pair 432, the second

revolute pair

431, and 430. The four first rotating pair 430, the second rotating pair 431, the third rotating pair 432 and the fourth rotating pair 433 are all spherical rotating pairs, and besides the positioning function of the positioning edge 530, the spherical rotating pairs have a self-centering and self-stabilizing function, so that the centers of the spherical bodies 275 on one side of the ball pins 225 of the upper connecting rod 310, the lower connecting rod 320 and the elephant foot assembly 290 can be ensured to be positioned on the same vertical axis.

In the "closed" position (FIG. 11), the upper and lower links 310, 320 are centered on the ball 275 on one side of the ball pin 225 of the elephant foot assembly 290, with the upper and lower links 310, 320 forming an inclined angle; meanwhile, the compression spring 340 acts on the brake piston 330, and an upward acting force is formed on the fourth revolute pair 433 between the lower end surface of the lower connecting rod 320 and the upper end surface of the brake piston 330, and since the ball pin 225 of the elephant foot assembly 290 is fixed on the elephant foot 250, the acting force generates a friction force among the 4 first revolute pairs 430, the second revolute pair 431, the third revolute pair 432 and the fourth revolute pair 433, so that the mutual movement of the upper connecting rod 310, one side ball 275 of the ball pin 225 of the elephant foot assembly 290 and the lower connecting rod 320 can be limited; at the same time, the locating edge 425 of the ball pin 225 of the elephant foot assembly 290 also limits the relative movement of the upper link 310, the one side ball 275 of the ball pin 225 of the elephant foot assembly 290 and the lower link 320, such that the upper link 310 and the lower link 320 remain in an angularly inclined position when in the "closed" position.

The working process of the example 2 is as follows:

when the engine valve driving device 105 is required to operate, the engine valve driving control mechanism (not shown) is opened to supply oil, the oil is supplied to the horizontal channel 130 through an oil circuit network (not shown) of the engine via an oil circuit 110 in the case 100 (see fig. 1), the oil pressure acts on the elephant foot 250 of the elephant foot assembly 290, the elephant foot 250 of the elephant foot assembly 290 moves, the elephant foot 250 pushes one side ball 265 of the ball pin 225, the motion is transmitted through the ball pin 225, one side ball 275 of the ball pin 225 pushes the upper connecting rod 310 and the lower connecting rod 320, the ball pin 227 of the elephant foot assembly 290 drives the upper connecting rod 310 and the lower connecting rod 320 to overcome the acting force of the return spring 240 and the compression spring 340 to push from the 'closed' position (fig. 11, inclined angle position) to the 'open' position (fig. 12, vertical coaxial position), the brake piston 330 connected with the bottom of the lower connecting rod 320 is changed from the retracted position to the extended position, the valve actuation device 105 is switched from the rest position to the operating position with its bottom surface (lower end surface) 434 adjacent (connected) to the lower engine valve. At this point, motion of an engine cam (not shown) is transferred to the engine valve via the rocker arm and the valve actuation device 105 in the operating position within the rocker arm to produce a desired valve motion, such as for engine braking.

When the engine valve actuating device 105 is not required to work, the engine brake control mechanism is closed to discharge oil, the elephant foot 250 of the elephant foot assembly 290 is not subjected to oil pressure and is reset under the action of the reset spring 240, and the elephant foot 250 of the elephant foot assembly 290 is stopped on the bottom surface 120 of the horizontal channel 130. The elephant foot 250 moves the one side ball 265 of the ball pin 225 and the motion is transferred through the ball pin 225 and the one side ball 275 of the ball pin 225 moves the upper link 310 and the lower link 320. The upper and lower connecting

rods

310 and 320 are brought back from vertical alignment (fig. 12) to an inclined angle (fig. 11), the brake piston 330 is retracted upwardly within the vertical channel 140 by the compression spring 340, and its bottom surface (lower end surface) 434 is spaced from the underlying engine valve to create a gap such that the motion of the engine cam (not shown) is skipped and not transferred to the engine valve without valve motion.

The examples of the present invention are illustrative of the present invention and not limiting thereof. In fact, it will be apparent to those skilled in the art that modifications and variations can be made in the present invention without departing from the scope and spirit of the invention. For example, some portion of the functionality illustrated or described for one particular mechanism may be used for another particular mechanism to yield a new mechanism. The box body in the embodiment can be not only a rocker arm, but also a valve bridge or even a fixed box body. In addition, the revolute pairs formed between the upper link and the case (the adjusting bolt), between the upper link and the ball pin of the elephant foot assembly, between the ball pin of the elephant foot assembly and the lower link, and between the lower link and the brake piston may also be cylindrical or other links. Also the guiding and positioning of the upper and lower connecting rods can be made in different ways, as well as the foot-like structure of the ball pin and the driving piston of the foot-like assembly. The engine valve actuation device of the present invention may produce other types of variable valve motion in addition to the valve motion that may be produced by engine braking. Thus, the present invention is intended to embrace such modifications and variations as fall within the scope of the appended claims or equivalents thereof.

Claims

1. A valve-driving apparatus of an engine, characterized in that: the valve driving device comprises a box body, an upper connecting rod, a lower connecting rod, a braking piston and a elephant foot component, wherein a vertical channel and a horizontal channel are arranged in the box body, the vertical channel is communicated with the horizontal channel, the upper connecting rod and the lower connecting rod are arranged in the vertical channel, and the braking piston is arranged at the lower part of the vertical channel; the elephant foot component is arranged in the horizontal channel; the elephant foot component comprises an elephant foot and a ball pin, wherein a ball socket used for containing and limiting the ball pin is arranged on the elephant foot, balls are arranged on two sides of the ball pin, one side of each ball pin is limited in the ball socket, and the other side of each ball pin is in limiting connection with the upper connecting rod and the lower connecting rod through contact surfaces of the balls.

2. A valve-driving apparatus of an engine according to claim 1, characterized in that: the lower end of the upper connecting rod and a ball body at one side of the ball pin of the elephant foot component form a revolute pair, and the upper end of the lower connecting rod and a ball body at one side of the ball pin of the elephant foot component form a revolute pair; and a revolute pair is arranged between the lower end of the lower connecting rod and the brake piston.

3. A valve-driving apparatus of an engine according to claim 1, characterized in that: the elephant foot component is provided with a return spring, one end of the return spring is fixed on the elephant foot component, and the other end of the return spring is fixed in the horizontal channel.

4. A valve-driving apparatus of an engine according to claim 1, characterized in that: and an engine oil path is arranged in the box body and is communicated with the horizontal channel, and the engine oil path connects the horizontal channel with an engine oil path network of the engine.

5. A valve-driving apparatus of an engine according to claim 1, characterized in that: the lower part of the box body is provided with a spring seat, a compression spring is fixedly arranged on the spring seat, and the upper end of the compression spring is connected to the brake piston.

6. A valve-driving apparatus of an engine according to claim 1, characterized in that: the horizontal channel is internally provided with a limiting block, the limiting block is provided with a limiting groove, the upper connecting rod, the lower connecting rod and the ball pin of the elephant foot component are positioned in the limiting groove, and the width of the limiting groove is slightly larger than that of the upper connecting rod, the lower connecting rod and the ball pin of the elephant foot component; the upper connecting rod and the lower connecting rod do plane motion along the limiting groove between a closing position and an opening position, an included angle is formed between the upper connecting rod and the lower connecting rod at the closing position, and the lower end face of the brake piston retracts; in the open position, the upper and lower connecting rods are positioned on a vertical coaxial line, and the lower end face of the brake piston extends out.

7. A valve-driving apparatus of an engine according to claim 6, characterized in that: the limiting block is provided with a positioning edge, and the positioning edge can prevent the upper connecting rod and the lower connecting rod from slipping.

8. A valve-driving apparatus of an engine according to claim 1, characterized in that: the ball pin of the elephant foot component is provided with a positioning edge, and the positioning edge can prevent the upper connecting rod and the lower connecting rod from slipping.

9. A valve-driving apparatus of an engine according to claim 1, characterized in that: the box body is provided with a valve clearance adjusting bolt, and the bottom surface of the valve clearance adjusting bolt is matched with the upper end of the upper connecting rod to form a revolute pair.

10. A valve-driving apparatus of an engine according to claim 1, characterized in that: the box on be provided with the discharge orifice, the vertical passageway that discharge orifice will communicate with the external world.

11. A valve-driving apparatus of an engine according to claim 1, characterized in that: the box body is a rocker arm or a valve bridge of an engine valve mechanism.

12. A valve driving method of an engine is characterized in that when the valve driving device of the engine needs to work, a control mechanism for driving the engine valve is opened to provide engine oil, the engine oil passes through an engine oil path network of the engine and provides engine oil pressure to a horizontal channel through an engine oil path in a box body, the engine oil pressure acts on an elephant foot of an elephant foot assembly, the elephant foot pushes a ball body on one side of a ball pin, the movement is transmitted through the ball pin, the ball body on the other side of the ball pin pushes an upper connecting rod and a lower connecting rod and pushes the upper connecting rod and the lower connecting rod to an opening position from a closing position along a limiting groove, namely, from an inclined included angle position to a vertical coaxial position, a brake piston connected with the bottom of the lower connecting rod generates height change and changes from a retraction position to an extension position, the bottom surface of the brake piston is close to the engine valve below, and the valve driving device is switched to a working position from a non-working position; the motion of the engine cam is transmitted to the engine valve through the rocker arm and a valve driving device at a working position in the rocker arm to generate the required valve motion;

when the engine valve driving device is not needed to work, the engine brake control mechanism is closed to unload the engine oil, the elephant foot of the elephant foot component is not subjected to the pressure of the engine oil and is reset under the action of the reset spring, the elephant foot of the elephant foot component stops at the bottom surface of the horizontal channel, the elephant foot drives a ball body on one side of the ball pin, the motion is transmitted through the ball pin, and the ball body on the other side of the ball pin drives the upper connecting rod and the lower connecting rod; the upper connecting rod and the lower connecting rod are changed from the opening position to the closing position, namely from the vertical coaxial position to the inclined included angle position, the braking piston connected with the bottom of the lower connecting rod generates height change and is changed from the extending position to the retracting position, the bottom surface of the braking piston is separated from the engine valve below to generate a certain distance, and the valve driving device is switched from the working position to the non-working position; so that the motion of the engine cam is skipped and cannot be transmitted to the engine valve without generating valve motion.