CN118188094A - Full-variable liquid valve system - Google Patents

Abstract

A fully variable electro-hydraulic valve system, comprising: the hydraulic control device comprises a sliding sleeve, a main plunger, a piston and a plunger return spring, wherein the main plunger is in transmission connection with a rotary mechanism, a charging and discharging oil way is internally provided with a hydraulic control switch valve and an electromagnetic reversing valve, and the electromagnetic reversing valve enables a hydraulic control port of the hydraulic control switch valve to be selectively communicated with an engine oil way or an oil pan so as to control the sliding sleeve cavity to be communicated with or disconnected from the engine oil way; the rotary mechanism is driven by the linkage plunger coupling part and is reversely reset through the return spring, and the linkage plunger coupling part is selectively communicated with an engine oil way or an oil pan of the engine through the same electromagnetic reversing valve, so that the system is in a rigid or non-rigid connection state. The system can independently control each valve and each cycle of the engine, solves the problem that the oil pressure is not invalid before the engine is started, is suitable for large-sized high-speed engines, and has higher reliability.

Description

Full-variable liquid valve system

Technical Field

The invention relates to the technical field of engine valve mechanisms, in particular to a fully variable liquid valve system.

Background

The full Variable valve system (FVVS for short) can realize continuous Variable of the valve maximum lift, the valve opening continuous angle and the valve timing, and has important significance for energy conservation and emission reduction of the engine. FVVS technology has become one of the important developments in new technologies for internal combustion engines.

Chinese patent CN209053652U discloses a full-variable electrohydraulic valve mechanism, which is characterized in that the valve motion is controlled by a cam shaft and an electromagnetic valve in a combined way, so that the response speed is high, the control is convenient, hydraulic oil in a sliding sleeve cavity can slowly leak in the engine stopping process, and the phenomenon of oil-free in the sliding sleeve cavity can occur when the engine is started, so that the system fails to work.

In order to solve the above problems, chinese patent No. CN110985155A discloses a fully variable hydraulic valve system, which is provided with a variable valve rigid connection device, after the engine is stopped, the plunger rotates to the rigid connection position under the action of spring force, the end face of the piston abuts against the end face of the plunger, engine oil does not act, the camshaft and the valve are in the rigid connection state, and the valve lift of the valve assembly is fully controlled by the camshaft, so as to avoid the influence of engine oil loss on the normal operation of the system.

In application, it is found that: according to the novel Chinese patent CN209053652U, each cylinder is controlled by an independent electromagnetic valve, for example, the cylinder stopping function of individual cylinders of the engine can be realized, the electromagnetic valve is generally an on-off electromagnetic valve, the on-off response time is not more than 5ms, the best can reach below 2ms, and the novel Chinese patent CN209053652U can adapt to the requirements of a high-speed engine. In the chinese patent CN110985155A, the actuating mechanism and the rack-and-pinion mechanism are used to control the opening of the valve, so that the inertia of the mechanism is relatively large, if a motor and a speed reducing mechanism are used as the actuating mechanism, even if a mode of controlling each cylinder separately is adopted (i.e. 6 actuating mechanisms are arranged in a six-cylinder machine), the response time is generally about 50 ms to 200ms, and if a proportion electromagnet with a relatively high price is used as the actuating mechanism, the response time is generally greater than 20ms; when six cylinders share one actuator, the response speed is slower. Referring to fig. 14, for an engine with a speed of 6000r/min, the time per revolution is 10ms, the time per cycle (720 ° CA) of four strokes is 20ms, the valve opening/closing time is typically 6.7ms (240 ° CA), and the time to the next valve opening is 13.3ms (480 ° CA). Because the Chinese novel patent CN209053652U adopts an electromagnetic valve, the response time is not more than 6.7ms, and the requirements can be met; however, since the chinese patent CN110985155A uses the rack and pinion mechanism as the actuator, the response time is longer than 13.3ms, which cannot meet the requirements, and the application is limited on the high-speed engine, the flow required by the large-scale engine is large, and the response of the related valve is affected by the large flow, so the limitation is more obvious. In addition, the solenoid valve controlling the valve sometimes fails, and if the valve cannot be switched to the 'rigid state' in time, the valve cannot be opened, resulting in larger failure of the engine.

Disclosure of Invention

In view of the above, the invention provides a fully variable hydraulic valve system which can independently control each valve and each cycle of an engine, solves the problem of failure before oil pressure is not established when the engine is started, is suitable for a large-sized high-speed engine, and has higher reliability.

In order to solve the technical problems, the invention adopts the following technical scheme:

A fully variable electro-hydraulic valve system, comprising: a camshaft and valve assembly; the piston is clamped between the main plunger and the piston, the piston is propped against the valve assembly, and the main plunger is axially controlled by a cam surface of the cam shaft; the main plunger is in transmission connection with a rotation mechanism; the sliding sleeve is provided with a positioning pin, the piston is provided with a guide groove extending along the axial direction, and the positioning pin stretches into the guide groove to limit the piston to rotate; the sliding sleeve is provided with an oil through hole communicated with the sliding sleeve cavity; the oil through hole is connected with a charging and discharging oil way, a hydraulic control switch valve and an electromagnetic reversing valve for controlling the hydraulic control switch valve to be opened and closed are arranged in the charging and discharging oil way, and the electromagnetic reversing valve enables a hydraulic control port of the hydraulic control switch valve to be selectively communicated with an engine oil way or an oil pan so as to control the sliding sleeve cavity to be communicated with or disconnected from the engine oil way; the rotary mechanism is driven by a linkage plunger matching part and is reversely reset through a return spring, the linkage plunger matching part is selectively communicated with an engine oil way or an oil pan of the engine through the electromagnetic reversing valve, and the linkage plunger matching part comprises a linkage plunger and a linkage plunger sleeve; a plunger boss is arranged at one end of the main plunger, and a piston boss is arranged at one end of the piston; when the electromagnetic reversing valve stops and is powered off, the hydraulic control switch valve is opened, the oil filling and discharging path is communicated, the electromagnetic reversing valve is communicated with the oil pan, the rotary mechanism is pushed to move reversely under the action of the return spring, the piston boss is enabled to be propped against and aligned with the end face of the plunger boss, the valve lift of the valve assembly is controlled by the cam shaft, and the system is in a rigid connection state; when the electromagnetic reversing valve is electrified, the hydraulic control switch valve is closed, the oil filling and discharging path is disconnected, the engine oil path of the engine is connected with the linkage plunger coupling part, the spring force of the return spring is overcome, the slewing mechanism is pushed to move, the plunger boss is dislocated circumferentially relative to the piston boss, the system is in a non-rigid connection state, and the variable valve starts to work; in the running of the engine, the power-on operation of the electromagnetic directional valve is carried out in a time period from the valve closing time of the last cycle to the valve opening time of the next cycle, and when the electromagnetic directional valve is powered off and the opened valve is controlled to start to be closed, the system is converted to a rigid connection state and finally returns to the rigid connection state.

The sliding sleeve is provided with a bleed hole communicated with the oil pan, and when the main plunger is in a return state, the bleed hole is closer to the main plunger relative to the oil through hole.

The rotary mechanism comprises a control gear and a rack which are meshed with each other, the control gear is connected with the main plunger in a torque transmission mode, the return spring is a compression spring, and the rack abuts against the linkage plunger under the action of the return spring.

The rotary mechanism comprises a control panel and a hinge pin, the control panel is connected with the main plunger in a torque transmission mode, the hinge pin is eccentrically fixed on the control panel, a transverse open slot is formed in the linkage plunger, and the hinge pin is movably arranged in the transverse open slot; the return spring is an extension spring connected with the linkage plunger, the extension spring is arranged in the linkage plunger sleeve, or the return spring is a compression spring, the compression spring props against the outer side of the linkage plunger, or the return spring is a torsion spring, and the torsion spring is connected between the hinge pin shaft and the control panel.

The rotary mechanism comprises a control panel and a hinge pin, the control panel is connected with the main plunger in a torque transmission mode, the hinge pin is fixed on the linkage plunger, a transverse open slot is formed in the control panel, and the hinge pin is movably arranged in the transverse open slot; the return spring is an extension spring connected with the linkage plunger, the extension spring is arranged in the linkage plunger sleeve, or the return spring is a compression spring, the compression spring props against the outer side of the linkage plunger, or the return spring is a torsion spring, and the torsion spring is connected between the hinge pin shaft and the control panel.

Wherein, the hydraulically controlled switching valve includes: the valve body comprises a first valve body and a second valve body which are axially arranged and fixedly connected together, and the switching valve return spring is positioned in the first valve body and clamped between the gland and the valve core; the first valve body is provided with a first cavity and a first oil port communicated with the first cavity, and the second valve body is provided with a second cavity and a second oil port communicated with the second cavity; the first oil port is communicated with the oil through port, and the second oil port is communicated with the engine oil way; the valve core comprises a first valve core section and a second valve core section with the same outer diameter, an annular groove is arranged between the first valve core section and the second valve core section, the annular groove corresponds to the first cavity, the first valve core section is in sliding fit with the first valve body, the second valve core section is in sliding fit with the second valve body, a flange is arranged at the position, close to the annular groove, of the second valve core section, a valve core sealing conical surface is arranged on the flange, when the electromagnetic reversing valve is electrified, the hydraulic control port is communicated with an engine oil circuit, the valve core sealing conical surface abuts against a sealing surface of the first valve body, the first cavity is disconnected from the second cavity, and the hydraulic control switch valve is closed; when the electromagnetic reversing valve is powered off, the electromagnetic reversing valve is communicated with the oil pan, the first cavity is communicated with the second cavity under the action of the switching valve reset spring, and the hydraulic control switching valve is opened. Or alternatively

The hydraulic control switching valve includes: the valve comprises a valve body, a valve core, a switching valve reset spring and a gland, wherein the switching valve reset spring is positioned in the valve body and is clamped between the gland and the valve core; the valve body is provided with a first cavity and a first oil port communicated with the first cavity, and is also provided with a second cavity and a second oil port communicated with the second cavity; the first oil port is communicated with the oil through port, and the second oil port is communicated with the engine oil way; the valve core comprises a first valve core section and a second valve core section with the same outer diameter, an annular groove is arranged between the first valve core section and the second valve core section, the annular groove corresponds to the first cavity in position, the first valve core section and the second valve core section are respectively in sliding fit with the valve body, when the electromagnetic reversing valve is electrified, the hydraulic control port is communicated with an engine oil circuit of the engine, the second valve core section and the second valve body form cylindrical surface sealing, the first cavity is disconnected with the second cavity, and the hydraulic control switch valve is closed; when the electromagnetic reversing valve is powered off, the electromagnetic reversing valve is communicated with the oil pan, the first cavity is communicated with the second cavity under the action of the switching valve reset spring, and the hydraulic control switching valve is opened.

Wherein, the electromagnetic reversing valve is a two-position three-way electromagnetic reversing valve.

After the technical scheme is adopted, the invention has the following technical effects:

The main plunger is in transmission connection with a slewing mechanism, the slewing mechanism is driven by a linkage plunger coupling and reversely reset through a return spring, the linkage plunger coupling is selectively communicated with the engine oil way or the oil pan through the electromagnetic reversing valve, the electromagnetic reversing valve is powered off after the engine is stopped, the electromagnetic reversing valve is communicated with the oil pan, the plunger boss is in propping alignment with the end face of the piston boss under the action of the return spring, and the system is in a rigid connection state; when the engine is started, the electromagnetic reversing valve is controlled to be powered off, the piston boss is propped against the end face of the plunger boss, the motion of the cam shaft is transmitted to the valve, the variable valve mechanism is still in a rigid connection state and works independently of hydraulic oil, and the valve lift of the valve assembly is controlled by the cam shaft, so that the influence of engine oil loss on the normal operation of the system is avoided; after the engine is started successfully, the electric control unit detects that the oil temperature and the oil pressure of the engine reach set values, the electromagnetic directional valve is electrified, the engine oil way is communicated with the linkage plunger coupling part, the spring force of the return spring is overcome, the slewing mechanism is pushed to move, the plunger boss is dislocated relative to the circumference of the piston boss, the system is in a non-rigid connection state, the variable valve starts to work, at the moment, the system can realize the function of the variable valve under the control of the hydraulic control switch valve and the electromagnetic directional valve, and the opening and closing of the hydraulic control switch valve with larger flow rate are controlled by using the electromagnetic directional valve with smaller flow rate, so that the hydraulic control switch valve can maintain high response when meeting the large flow rate, and therefore, the system not only solves the problem that the oil pressure is not established before the engine is started, but also is suitable for being used for a large-sized high-speed engine. In addition, because the linkage plunger coupling part and the hydraulic control switch valve share one electromagnetic directional valve, when the electromagnetic directional valve is powered off and the valve which is controlled to be opened starts to be closed in the operation of the engine, the system is converted to a rigid connection state and finally returns to the rigid connection state, namely, each cycle of the engine, the variable valve system is converted from the rigid state to the non-rigid state, and the energization operation of the electromagnetic directional valve is carried out in the time period from the valve closing time of the last cycle to the valve opening time of the next cycle, so that the relatively abundant response time is provided for the electromagnetic directional valve, and the requirement on the electromagnetic directional valve is reduced. Based on this, this system can carry out independent control to every valve, every circulation of engine, and the electromagnetic change valve can all be through outage automatic switching to the rigidity state when breaking down at any time moreover, and the reliability is higher.

In the invention, the sliding sleeve is provided with the air release hole communicated with the oil pan, and when the main plunger is in a return state, the air release hole is closer to the main plunger relative to the oil through hole. Before the cam drives the main plunger, the sliding sleeve cavity is exhausted through the air release hole, engine oil is continuously discharged, the heat exchange effect is achieved, and the oil temperature in the cavity is prevented from being too high. When the valve is in a non-rigid connection state, the main plunger moves for a small distance, so that the vent hole can be blocked, but the stroke loss of the valve can be caused, and in order to compensate the loss, a cam molded line can be designed for compensation.

In the invention, the slewing mechanism driving the main plunger to reciprocate can be a gear-rack mechanism, or can be a mechanism consisting of a control panel and a hinge pin, wherein the hinge pin is eccentrically arranged relative to the circle center of the control panel, and when the linkage plunger makes reciprocating rectilinear motion, the hinge pin can drive the control panel to drive the main plunger to reciprocate. The return spring may be an extension spring, a rotation spring, a compression spring, or the like. The mechanism is simpler than a rack and pinion mechanism.

In the invention, the valve core of the hydraulic control switch valve is provided with the first valve core section and the second valve core section, and the outer diameters of the two valve core sections are the same, so that the resultant force of the acting force of hydraulic oil in the first cavity and the second cavity on the valve core is zero no matter the switch valve is in a closed state or an open state, thereby ensuring the quick response performance of the switch valve. The valve core and the valve body can adopt conical surface sealing, cylindrical surface sealing and sealing, when the conical surface sealing is adopted, the sealing effect is good, but the valve body is required to be arranged in a split mode due to installation requirements, and when the cylindrical surface sealing is adopted, the valve body does not need to be arranged in a split mode although the sealing performance is slightly poor, the structure is more compact, and the process is simpler.

Drawings

Fig. 1 is a structural sectional view of embodiment 1 of the all-variable liquid valve system of the present invention;

FIG. 2 is a graph of engine crank angle/valve lift for the embodiment 1 of FIG. 1;

FIG. 3 is a schematic perspective view of the main plunger of FIG. 1;

FIG. 4 is a schematic perspective view of the piston of FIG. 1;

FIG. 5 is a schematic illustration of the plunger boss of FIG. 1 in abutting alignment with respect to the end face of the plunger boss;

FIG. 6 is a schematic view of the plunger boss of FIG. 1 in a circumferentially offset position relative to the plunger boss;

FIG. 7 is a schematic view of the hydraulic control switch valve in FIG. 1 in an open state;

FIG. 8 is a schematic structural view of the pilot operated switching valve spool of FIG. 7;

Fig. 9 is a schematic structural view of the hydraulic control switching valve in the closed state in embodiment 2 of the fully variable hydraulic valve system of the present invention;

fig. 10 is a schematic diagram of the structure of the hydraulic control switching valve in the opened state in embodiment 2 of the fully variable hydraulic valve system according to the present invention;

FIG. 11 is a schematic view of the pilot operated switching valve cartridge of FIG. 10;

fig. 12 is a schematic structural view of embodiment 3 of the fully variable liquid valve system of the present invention;

fig. 13 is a schematic structural view of embodiment 4 of the fully variable liquid valve system of the present invention;

FIG. 14 is a graph of crank angle/valve lift for a conventional four-stroke engine;

In the figure, 101, camshaft; 102. a main plunger; 102A, control gear; 102B, plunger boss; 102C, a control panel; 103. a sliding sleeve; 103A, oil holes; 103B, bleed holes; 104. a plunger return spring; 105. a piston; 105A, piston boss; 105B, guide slots; 106. a valve assembly;

107. a hydraulically controlled switching valve; 107A, gland; 107B, a first valve body; 107C, valve core; 107C1, a first spool segment; 107C2, a second spool segment; 107C3, flange; 107C4, a valve core sealing conical surface; 107C5, annular groove; 107D, a switching valve return spring; 107E, a second valve body; 107F, a second oil port; 107f, a second cavity; 107G, a first oil port; 107g, first chamber; 107H, a hydraulic control port;

108. An electromagnetic reversing valve; 109. an oil pan; 110. a one-way valve; 111. wear-resistant gaskets; 112. a thrust bearing; 113. an electromagnetic reversing valve;

114. A hydraulically controlled switching valve; 114A, gland; 114B, valve body; 114C, a valve core; 114C1, a first spool segment; 114C2, a second spool segment; 114C3, annular groove; 114D, a switching valve return spring; 114F, a first oil port; 114f, a first cavity; 114G, a second oil port; 114g, second chamber; 114H, pilot operated ports;

119. a positioning pin; 120. a linkage plunger sleeve; 121. a linkage plunger; 122. a rack; 123. a compression spring; 124. a hinge pin; 125. a tension spring; 126. a torsion spring;

Q, sliding sleeve cavity.

Detailed Description

The invention will be further described with reference to the drawings and examples.

Example 1

As shown in fig. 1, in a fully variable hydraulic valve system, a sliding sleeve 103 is fixed relative to an engine, a main plunger 102 and a piston 105 are respectively connected with the sliding sleeve 103 in a sliding and sealing manner, the main plunger 102 is axially controlled by a cam surface of a cam shaft 101, and the piston 105 is propped against a valve assembly 106. In the sliding sleeve 103, a space between the main plunger 102 and the piston 105 is a sliding sleeve cavity Q, and the plunger return spring 104 is sandwiched between the main plunger 102 and the piston 105.

The sliding sleeve 103 is provided with an oil through hole 103A and a gas release hole 103B which are communicated with the sliding sleeve cavity Q, the oil through hole 103A is connected with a charging and discharging oil path, in this embodiment, a hydraulic control switch valve 107 and an electromagnetic directional valve 108 for controlling the hydraulic control switch valve 107 to open and close are arranged in the charging and discharging oil path, and the electromagnetic directional valve 108 enables a hydraulic control port of the hydraulic control switch valve 107 to be selectively communicated with an engine oil path or an oil pan 109, so that the sliding sleeve cavity Q is controlled to be communicated with or disconnected from the engine oil path.

The main plunger 102 is in transmission connection with a rotation mechanism, the rotation mechanism is driven by a linkage plunger matching part and is reversely reset through a return spring, the linkage plunger matching part is selectively communicated with an engine oil way or an oil pan 109 through an electromagnetic reversing valve 108, and the linkage plunger matching part comprises a linkage plunger 121 and a linkage plunger sleeve 120. The turning mechanism is a rack-and-pinion mechanism, which includes a control gear 102A and a rack 122 that are meshed with each other, the control gear 102A is connected to the main plunger 102 in a manner of transmitting torque, and the control gear 102A is connected to the main plunger 102 in two manners, one being fixedly connected, and the other being relatively slidable in the axial direction but relatively non-rotatable, such as a key connection, with respect to the main plunger 102, regardless of the connection manner in which it must be capable of transmitting torque. The return spring is a compression spring 123, and under the action of the return spring, the rack 122 abuts against the linkage plunger 121. In this embodiment, a four-cylinder four-stroke engine is taken as an example, one rack-and-pinion mechanism corresponds to one linkage plunger coupling, and the control gear 102A of each main plunger 102 can be independently and flexibly controlled by using one electromagnetic directional valve, so that the response time is short.

As shown in fig. 1 and 4, the sliding sleeve 103 is provided with a positioning pin 119, the piston 105 is provided with a guide groove 105B extending along the axial direction, and the positioning pin 119 extends into the guide groove 105B to limit the rotation of the piston 105. One end of the piston 105 is provided with two piston bosses 105A, and the two piston bosses 105A are symmetrically disposed with respect to the center of the piston 105.

As shown in fig. 3, two plunger bosses 102B are provided at one end of the main plunger 102, the two plunger bosses 102B are symmetrically provided with respect to the center of the main plunger 102, and the plunger bosses 102B are in one-to-one correspondence with the piston bosses 105A.

As shown in fig. 6, when the electromagnetic directional valve 108 is energized, the engine oil circuit is connected with the linkage plunger coupling, and overcomes the spring force of the return spring, the rotation mechanism is pushed to move, so that the plunger boss 102B is dislocated circumferentially relative to the piston boss 105A, and the system is in a non-rigid connection state.

As shown in fig. 5, when the electromagnetic directional valve 108 is powered off, the linkage plunger coupling is communicated with the oil pan 109, and under the action of the return spring, the rotary mechanism is pushed to move reversely, so that the piston boss 105A is aligned with the end face of the plunger boss 102B in a propping way, the valve lift of the valve assembly 106 is controlled by the cam shaft 101, and the system is in a rigid connection state.

In the present embodiment, as shown in fig. 1, the relief hole 103B communicates with the oil pan 109, and the relief hole 103B is closer to the main plunger 102 than the oil passage hole 103A when the main plunger 103 is in the return state. Before the camshaft 101 drives the main plunger 102, the sliding sleeve cavity Q is exhausted through the air release hole 103B, engine oil is continuously discharged, the heat exchange effect is achieved, and the excessive high oil temperature in the cavity is avoided. When the non-rigid connection state works, the main plunger 102 moves a small distance to block the air release hole 103B, but the stroke loss of the air valve is caused, and in order to compensate the loss, a cam profile can be designed to compensate.

As shown in fig. 7 and 8, the hydraulic control switching valve 107 includes: the valve body comprises a first valve body 107B and a second valve body 107E which are axially arranged and fixedly connected together, a valve core 107C, a switching valve return spring 107D and a gland 107A, wherein the switching valve return spring 107D is positioned in the first valve body 107B and is clamped between the gland 107A and the valve core 107C. The first valve body 107B is provided with a first chamber 107G and a first oil port 107G communicating with the first chamber 107G, and the second valve body 107E is provided with a second chamber 107F and a second oil port 107F communicating with the second chamber 107F; the first oil port 107G is communicated with the oil through port 103A, and the second oil port 107F is communicated with the engine oil circuit; the valve core comprises a first valve core section 107C1 and a second valve core section 107C2 with the same outer diameter (d), an annular groove 107C5 is arranged between the first valve core section 107C1 and the second valve core section 107C2, the annular groove 107C5 corresponds to the first cavity 107g in position, the first valve core section 107C1 is in sliding fit with the first valve body 107B, the second valve core section 107C2 is in sliding fit with the second valve body 107E, a flange 107C3 is arranged at a position close to the annular groove 107C5 of the second valve core section 107C2, the flange 107C3 is provided with a valve core sealing conical surface 107C4, when the electromagnetic reversing valve 108 is electrified, a hydraulic control port 107H is communicated with an engine oil way of the engine, the valve core sealing conical surface 107C4 abuts against a sealing surface of the first valve body 107B, the first cavity 107g is disconnected from the second cavity 107f, and the hydraulic control switch valve 107 is closed; when the electromagnetic directional valve 108 is de-energized, the electromagnetic directional valve 108 is turned on with the oil pan 109, the first chamber 107g is communicated with the second chamber 107f by the on-off valve return spring 107D, and the pilot operated on-off valve 107 is opened.

Because the outer diameters of the two spool segments are the same, the resultant force of the hydraulic oil in the first chamber 107g and the second chamber 107f on the spool 107C is zero no matter whether the switching valve is in the closed state or the open state, thereby ensuring the quick response performance of the switching valve.

The working principle of the invention is as follows:

After the engine is stopped, the electromagnetic directional valve 108 is powered off, the linkage plunger coupling is communicated with the oil pan 109, the plunger boss 102B is propped against and aligned with the end face of the piston boss 105A under the action of the return spring, and the system is in a rigid connection state. When the engine is started, the electromagnetic reversing valve 108 is controlled to be powered off, the piston boss 105A is abutted against the end face of the plunger boss 102B, the motion of the cam shaft is transmitted to the valve, the variable valve mechanism is still in a rigid connection state and works independently of hydraulic oil, the valve lift of the valve assembly 106 is controlled by the cam shaft, and therefore the influence of engine oil loss on the normal operation of the system is avoided. After the engine is started successfully, the electric control unit detects that the oil temperature and the oil pressure of the engine reach set values, the engine oil way is communicated with the linkage plunger coupling part, the spring force of the return spring is overcome, the rotation mechanism is pushed to move, the plunger boss 102B is dislocated circumferentially relative to the piston boss 105A, the system is in a non-rigid connection state, the variable valve starts to work, at the moment, the function of the variable valve can be realized under the control of the hydraulic control switch valve 107 and the electromagnetic directional valve 108, and the opening and closing of the hydraulic control switch valve 107 with larger flow rate are controlled by using the electromagnetic directional valve 108 with smaller flow rate, so that the hydraulic control switch valve 108 can keep high responsiveness while meeting the large flow rate, and therefore, the system not only solves the problem that the oil pressure is not built before the engine is started, but also is suitable for being used for a large-sized high-speed engine. Moreover, since the linkage plunger coupling and the hydraulic control switch valve 107 share one electromagnetic directional valve 108, when the electromagnetic directional valve 108 is powered off and the valve which is controlled to be opened starts to be closed in the engine operation, the system is converted to the rigid connection state and finally returns to the rigid connection state, namely, the variable valve system is converted to the rigid-non-rigid state in each cycle of the engine, and the energizing operation of the electromagnetic directional valve 108 is carried out in the period from the valve closing time of the last cycle to the valve opening time of the next cycle, as shown in fig. 2, so that the relatively abundant response time is provided for the electromagnetic directional valve 108 (refer to the 6000r/min high-speed engine, and the period is 13.3ms (480 DEG CA)), thereby reducing the requirement on the electromagnetic directional valve. Based on this, this system can carry out independent control to every valve, every circulation of engine, and the electromagnetic change valve can all be through outage automatic switching to the rigidity state when breaking down at any time moreover, and the reliability is higher.

In this embodiment, a thrust bearing 112 is disposed on the end face of the control gear 102A, a wear-resistant spacer 111 is disposed between the thrust bearing 112 and the cam surface of the cam shaft 101 to reduce wear, and the distance between the piston boss 105A and the plunger boss 102B can be adjusted by the thickness of the wear-resistant plate 111, when the non-cam surface of the cam shaft 101 abuts against the main plunger 102 (or by the wear-resistant plate 111 and the thrust bearing 112), the distance therebetween is zero or nearly zero.

In this embodiment, the electromagnetic directional valve 108 is preferably a two-position three-way electromagnetic directional valve.

Example 2

As shown in fig. 9, 10 and 11, the structure of the present embodiment is substantially the same as that of embodiment 1, except that the present embodiment employs a pilot operated switching valve 114 capable of achieving "cylindrical sealing", and the pilot operated switching valve 114 includes: a valve body 114B, a valve core 114C, a switching valve return spring 114D, and a gland 114A, the switching valve return spring 114D being located within the valve body 114B and sandwiched between the gland 114A and the valve core 114C; the valve body 114B is provided with a first cavity 114F and a first oil port 114F communicating with the first cavity 114F, and the valve body 114B is also provided with a second cavity 114G and a second oil port 114G communicating with the second cavity 114G; the first oil port 114F is communicated with the oil through port 103A, and the second oil port 114G is communicated with the engine oil way; the spool 114C includes a first spool segment 114C1 and a second spool segment 114C2 with the same outer diameter, an annular groove 114C3 is disposed between the first spool segment 114C1 and the second spool segment 114C2, the annular groove 114C3 corresponds to the first cavity 114f, the first spool segment 114C1 and the second spool segment 114C2 are respectively in sliding fit with the valve body 114B, when the electromagnetic directional valve 108 is powered on, the hydraulic control port 114H is connected with the engine oil circuit, the second spool segment 114C2 forms cylindrical surface seal with the valve body 114B, the first cavity 114f is disconnected from the second cavity 114g, and the hydraulic control switch valve 114 is closed; when the electromagnetic directional valve 108 is de-energized, the electromagnetic directional valve 108 is connected to the oil pan 109, the first chamber 114f is connected to the second chamber 114g by the switching valve return spring 114D, and the pilot operated switching valve 114 is opened.

In the embodiment, the valve core and the valve body adopt cylindrical sealing, and the valve body does not need to be arranged in a split mode although the sealing performance is slightly poor, so that the structure is more compact, and the process is simpler. In the embodiment 1, the valve core and the valve body adopt conical surface sealing, so that the sealing effect is good, but the valve body needs to be arranged separately for installation.

Example 3

As shown in fig. 12, the structure of the present embodiment is basically the same as that of embodiment 1, except that the swing mechanism includes a control panel 102C and a hinge pin 124, the control panel 102C is connected with the main plunger 102 in a manner of transmitting torque, the hinge pin 124 is eccentrically fixed on the control panel 102C, a transverse open slot is formed on the linkage plunger 121, and the hinge pin 124 is movably disposed in the transverse open slot; the extension spring 125 is connected with the linkage plunger 121 to form a return spring, and the extension spring 125 is disposed in the linkage plunger sleeve 120. Of course, the return spring may also be provided as a compression spring that abuts against the outside of the linkage plunger 121, or as a torsion spring that is connected between the hinge pin 124 and the control disc 102C.

Example 4

As shown in fig. 13, the structure of the present embodiment is basically the same as that of embodiment 1, except that the swing mechanism includes a control panel 102C and a hinge pin 124, the control panel 102C is connected with the main plunger 102 in a manner of transmitting torque, the hinge pin 124 is fixed on the linkage plunger 121, a transverse open slot is formed on the control panel 102C, and the hinge pin 124 is movably disposed in the transverse open slot; a torsion spring 126 is provided between the hinge pin 124 and the control panel 102C, and the torsion spring 126 constitutes a return spring. Of course, the return spring may also be provided as a compression spring that abuts against the outside of the linked plunger 121, or as an extension spring as in embodiment 3.

The present invention is not limited to the above embodiments, and all modifications based on the concept, principle, structure and method of the present invention are included in the scope of the present invention.

Claims (10)

1. A fully variable electro-hydraulic valve system, comprising:

A camshaft and valve assembly;

The piston is clamped between the main plunger and the piston, the piston is propped against the valve assembly, and the main plunger is axially controlled by a cam surface of the cam shaft; the main plunger is in transmission connection with a rotation mechanism; the sliding sleeve is provided with a positioning pin, the piston is provided with a guide groove extending along the axial direction, and the positioning pin stretches into the guide groove to limit the piston to rotate; the sliding sleeve is provided with an oil through hole communicated with the sliding sleeve cavity; it is characterized in that the method comprises the steps of,

The oil through hole is connected with a charging and discharging oil way, a hydraulic control switch valve and an electromagnetic reversing valve for controlling the hydraulic control switch valve to be opened and closed are arranged in the charging and discharging oil way, and the electromagnetic reversing valve enables a hydraulic control port of the hydraulic control switch valve to be selectively communicated with an engine oil way or an oil pan so as to control the sliding sleeve cavity to be communicated with or disconnected from the engine oil way;

The rotary mechanism is driven by a linkage plunger matching part and is reversely reset through a return spring, the linkage plunger matching part is selectively communicated with an engine oil way or an oil pan of the engine through the electromagnetic reversing valve, and the linkage plunger matching part comprises a linkage plunger and a linkage plunger sleeve; a plunger boss is arranged at one end of the main plunger, and a piston boss is arranged at one end of the piston;

When the electromagnetic reversing valve stops and is powered off, the hydraulic control switch valve is opened, the oil filling and discharging path is communicated, the electromagnetic reversing valve is communicated with the oil pan, the rotary mechanism is pushed to move reversely under the action of the return spring, the piston boss is enabled to be propped against and aligned with the end face of the plunger boss, the valve lift of the valve assembly is controlled by the cam shaft, and the system is in a rigid connection state; when the electromagnetic reversing valve is electrified, the hydraulic control switch valve is closed, the oil filling and discharging path is disconnected, the engine oil path of the engine is connected with the linkage plunger coupling part, the spring force of the return spring is overcome, the slewing mechanism is pushed to move, the plunger boss is dislocated circumferentially relative to the piston boss, the system is in a non-rigid connection state, and the variable valve starts to work; in the running of the engine, the power-on operation of the electromagnetic directional valve is carried out in a time period from the valve closing time of the last cycle to the valve opening time of the next cycle, and when the electromagnetic directional valve is powered off and the opened valve is controlled to start to be closed, the system is converted to a rigid connection state and finally returns to the rigid connection state.

2. The fully variable hydraulic valve system of claim 1, wherein there are two plunger bosses, two piston bosses, and one-to-one correspondence between the plunger bosses and the piston bosses.

3. The fully variable hydraulic valve system of claim 2, wherein two of the plunger bosses are symmetrically disposed with respect to a center of the main plunger and two of the piston bosses are symmetrically disposed with respect to a center of the piston.

4. The fully variable hydraulic valve system of claim 1, wherein the sliding sleeve is provided with a bleed hole in communication with the oil pan, the bleed hole being closer to the main plunger than the oil passage hole when the main plunger is in the return state.

5. The fully variable hydraulic valve system of claim 1, wherein the swing mechanism includes a control gear and a rack that are intermeshed, the control gear being torsionally connected with the main plunger, the return spring being a compression spring, the rack being in abutment with the linked plunger under the action of the return spring.

6. The fully variable liquid valve system according to claim 1, wherein the slewing mechanism comprises a control panel and a hinge pin, the control panel is connected with the main plunger in a torque transmission manner, the hinge pin is eccentrically fixed on the control panel, a transverse open slot is formed in the linkage plunger, and the hinge pin is movably arranged in the transverse open slot; the return spring is an extension spring connected with the linkage plunger, the extension spring is arranged in the linkage plunger sleeve, or the return spring is a compression spring, the compression spring props against the outer side of the linkage plunger, or the return spring is a torsion spring, and the torsion spring is connected between the hinge pin shaft and the control panel.

7. The fully variable liquid valve system according to claim 1, wherein the slewing mechanism comprises a control panel and a hinge pin, the control panel is connected with the main plunger in a torque transmission manner, the hinge pin is fixed on the linkage plunger, a transverse open slot is formed in the control panel, and the hinge pin is movably arranged in the transverse open slot; the return spring is an extension spring connected with the linkage plunger, the extension spring is arranged in the linkage plunger sleeve, or the return spring is a compression spring, the compression spring props against the outer side of the linkage plunger, or the return spring is a torsion spring, and the torsion spring is connected between the hinge pin shaft and the control panel.

8. The fully variable liquid valve system of claim 1, wherein the pilot operated switching valve comprises: the valve body comprises a first valve body and a second valve body which are axially arranged and fixedly connected together, and the switching valve return spring is positioned in the first valve body and clamped between the gland and the valve core; the first valve body is provided with a first cavity and a first oil port communicated with the first cavity, and the second valve body is provided with a second cavity and a second oil port communicated with the second cavity; the first oil port is communicated with the oil through port, and the second oil port is communicated with the engine oil way; the valve core comprises a first valve core section and a second valve core section with the same outer diameter, an annular groove is arranged between the first valve core section and the second valve core section, the annular groove corresponds to the first cavity, the first valve core section is in sliding fit with the first valve body, the second valve core section is in sliding fit with the second valve body, a flange is arranged at the position, close to the annular groove, of the second valve core section, a valve core sealing conical surface is arranged on the flange, when the electromagnetic reversing valve is electrified, the hydraulic control port is communicated with an engine oil circuit, the valve core sealing conical surface abuts against a sealing surface of the first valve body, the first cavity is disconnected from the second cavity, and the hydraulic control switch valve is closed; when the electromagnetic reversing valve is powered off, the electromagnetic reversing valve is communicated with the oil pan, the first cavity is communicated with the second cavity under the action of the switching valve reset spring, and the hydraulic control switching valve is opened.

9. The fully variable liquid valve system of claim 1, wherein the pilot operated switching valve comprises: the valve comprises a valve body, a valve core, a switching valve reset spring and a gland, wherein the switching valve reset spring is positioned in the valve body and is clamped between the gland and the valve core; the valve body is provided with a first cavity and a first oil port communicated with the first cavity, and is also provided with a second cavity and a second oil port communicated with the second cavity; the first oil port is communicated with the oil through port, and the second oil port is communicated with the engine oil way; the valve core comprises a first valve core section and a second valve core section with the same outer diameter, an annular groove is arranged between the first valve core section and the second valve core section, the annular groove corresponds to the first cavity in position, the first valve core section and the second valve core section are respectively in sliding fit with the valve body, when the electromagnetic reversing valve is electrified, the hydraulic control port is communicated with an engine oil circuit of the engine, the second valve core section and the second valve body form cylindrical surface sealing, the first cavity is disconnected with the second cavity, and the hydraulic control switch valve is closed; when the electromagnetic reversing valve is powered off, the electromagnetic reversing valve is communicated with the oil pan, the first cavity is communicated with the second cavity under the action of the switching valve reset spring, and the hydraulic control switching valve is opened.

10. The fully variable hydraulic valve system of claim 1, wherein the electromagnetic directional valve is a two-position three-way electromagnetic directional valve.