CN109519248B

CN109519248B - Electric control valve mechanism, engine and automobile

Info

Publication number: CN109519248B
Application number: CN201710841784.4A
Authority: CN
Inventors: 徐旭初; 朱新星; 陶林杰; 张伯平; 李玄玄
Original assignee: SAIC Motor Corp Ltd
Current assignee: SAIC Motor Corp Ltd
Priority date: 2017-09-18
Filing date: 2017-09-18
Publication date: 2020-09-29
Anticipated expiration: 2037-09-18
Also published as: CN109519248A

Abstract

The invention discloses an electronic control valve mechanism, an engine and an automobile, which comprise a valve (1), a valve driving mechanism and a valve spring (2), wherein the valve driving mechanism comprises a shell (3), a motor (4), a planetary roller screw (5) and a push rod (6); the planetary roller screw (5) comprises a screw (51), rollers (52) and a nut (53) arranged on the periphery of the rollers, the rollers (52) are in meshing transmission with the screw (51), and the nut (53) is in meshing transmission with the rollers (52); the power output shaft of the motor (4) is connected with the lead screw (51), the nut (53) is connected with the push rod (6), and a guide mechanism is arranged between the nut (53) and the shell (3); the lower end of the push rod (6) pushes the air valve (1) to act. The electric control valve mechanism can adjust the valve timing and the valve lift according to the actual operation condition, thereby improving the performance of the engine, and reducing the oil consumption and the pollutant discharge.

Description

Electric control valve mechanism, engine and automobile

Technical Field

The invention relates to the technical field of automobile valve mechanisms, in particular to an electric control valve mechanism of an automobile. The invention also relates to an engine and an automobile provided with the electrically controlled valve mechanism.

Background

In the future, internal combustion engines must meet increasingly stringent carbon dioxide emissions and exhaust gas pollutant requirements, which will make the valve mechanism play a very important role. On the one hand, the valve train is to minimize losses in the ventilation cycle; on the other hand, the valvetrain must achieve as much in-cylinder mixing as possible in order to have optimal efficiency and low emissions during combustion. In addition, the combustion process can be directly influenced by adjusting the compression ratio and the amount of residual exhaust gas in the cylinder within a certain range.

There has therefore been a significant growth in the use of variable valve trains over the past few years, two common variable valve train solutions being as follows:

in the first approach, a cam phase adjuster is used to achieve temporary shifting of the valve lift profile, i.e., variable valve timing. The Variable Valve Timing (VVT) principle of an engine is to adjust the amount of intake (exhaust) air and the Valve opening/closing time and angle according to the operating condition of the engine. The air quantity entering the combustion chamber is optimized, and the combustion efficiency is improved.

When the automobile engine runs at a low speed, the inertia of airflow is small, if the air distribution timing is kept unchanged, part of air inflow is pushed out of the cylinder by the piston, so that the air inflow is reduced, and the residual waste gas in the cylinder is increased.

When the engine runs at a high speed, the airflow inertia is large, if the air inlet lag angle and the valve overlap angle are increased, the air inlet amount is increased and the residual waste gas amount is reduced, so that the air exchange process of the engine is perfected.

In the second scheme, the height of a valve lift curve and the positions of the opening and closing points of the valve are changed, and therefore the opening section of the valve, namely the variable valve lift, is changed. The valve structure of the traditional gasoline engine is shown in figure 1 and comprises a valve 1', a valve spring 2', a camshaft 3', a timing chain wheel 4' and the like, the adjustable valve timing is limited, the valve lift cannot be adjusted, the valve lift is fixed and unchangeable, namely only one cam profile of the camshaft is provided.

The cam profile design of a conventional gasoline engine is a balanced choice for the engine under all operating conditions, with the result that the engine neither obtains optimal high-speed efficiency nor optimal low-speed torque, and it is impossible to achieve good engine response in both the high-speed and low-speed regions.

Therefore, how to design a new valve mechanism to overcome the above defects is a technical problem to be solved by those skilled in the art.

Disclosure of Invention

The invention aims to provide an electrically controlled valve mechanism. The electric control valve mechanism can adjust the valve timing and the valve lift according to the actual operation condition, thereby improving the performance of the engine, and reducing the oil consumption and the pollutant discharge.

Another object of the present invention is to provide an engine provided with the electrically controlled valve mechanism.

It is a further object of the present invention to provide a vehicle provided with such an engine.

In order to achieve the purpose, the electric control valve mechanism comprises a valve, a valve driving mechanism and a valve spring for providing resetting force for the valve, wherein the valve driving mechanism comprises a shell, and a motor, a planetary roller screw and a push rod which are sequentially and axially arranged in the shell; the planetary roller screw comprises a screw rod, rollers which are circumferentially distributed by taking the screw rod as a center and a nut which is arranged on the periphery of the rollers, wherein the rollers are in meshing transmission with the screw rod, and the nut is in meshing transmission with the rollers; the power output shaft of the motor is connected with a screw rod of the planetary roller screw, a nut of the planetary roller screw is connected with the push rod, and a guide mechanism which limits circumferential rotation of the planetary roller screw and guides axial movement of the planetary roller screw is arranged between the nut and the shell; the lower end of the push rod extends out of the shell and is supported on the valve to push the valve to act.

Further, the roller of the planetary roller screw comprises a large-diameter section and a small-diameter section, the large-diameter section is meshed with the screw, and the small-diameter section is meshed with the nut; the large-diameter section of each roller is positioned in the middle of the roller, the small-diameter section of each roller comprises a first small-diameter section and a second small-diameter section, and the first small-diameter section and the second small-diameter section are respectively positioned at two ends of the large-diameter section; the nut is provided with a first internal thread and a second internal thread which are respectively meshed with the first small-diameter section and the second small-diameter section, and a certain distance is reserved between the first internal thread and the second internal thread.

Furthermore, the valve is a single valve, the axes of the motor, the planetary roller screw and the push rod coincide with the axis of the valve, and the lower end of the push rod extends out of the shell and is directly supported at the upper end of the valve.

Furthermore, the air valves are double air valves or multiple air valves, and the axes of the motor, the planetary roller screw and the push rod are parallel to the axis of the air valves; the upper end of the valve is fixedly connected with a pressing block, and the lower end of the push rod extends out of the shell and is supported on the pressing block.

Further, guiding mechanism is including locating slider on the nut surface with locate axial slide on the casing internal surface, the slider with slide axial sliding fit.

Further, the screw rod support is further included; the screw rod supporting piece is fixed in the shell and positioned between the motor and the planetary roller screw rod, and a bearing piece for supporting the screw rod to rotate is arranged between the through hole for penetrating through the screw rod and the screw rod.

Furthermore, the outer surface of the shell is provided with a positioning installation part for fixing the shell on an engine.

Further, the motor is integrated with a motor controller at the tail.

In order to achieve the second object, the present invention provides an engine, including a cylinder block, cylinders, and an intake valve and an exhaust valve corresponding to each of the cylinders, where the intake valve and the exhaust valve of each of the cylinders are the electrically controlled valve mechanism described in any one of the above.

In order to achieve the third object, the invention provides an automobile, which comprises an automobile body, an engine, a gearbox and wheels in transmission connection with a power output end of the gearbox, wherein the engine is provided with the electrically controlled valve mechanism.

The electric control valve mechanism provided by the invention is a valve mechanism controlled by a motor, and comprises a motor, a planetary roller screw, a push rod and other components, when the electric control valve mechanism works, the motor converts rotary motion into linear motion through the planetary roller screw, transmits power to the push rod, and then pushes the valve to act through the push rod, so that the function of opening and closing the valve is achieved. The valve action is controlled by the motor, so that the valve can be opened and closed at any time according to the requirement of the engine, the variable valve timing function in a large range is really realized, the combustion efficiency of the engine is improved, the emission is reduced, in addition, the valve opening degree can be steplessly adjusted in a certain area, the driving is free from any abrupt feeling, the comfort is stronger, the adaptability of the valve mechanism under each rotating speed is stronger, the engine inflation efficiency can be furthest improved, and the possibility of ECU calibration control can be greatly improved.

In addition, the planetary roller screw has the advantages of high bearing capacity, long service life, high efficiency, high volume power ratio, high quality power ratio and the like, and can ensure that the valve mechanism has smaller volume and longer service life while transmitting the same power.

The engine and the automobile provided by the invention are provided with the electric control valve mechanism, and the engine and the automobile provided with the electric control valve mechanism also have corresponding technical effects due to the technical effects of the electric control valve mechanism.

Drawings

FIG. 1 is a schematic structural view of a conventional valve train;

fig. 2 is a schematic structural diagram of an electronically controlled valve train according to an embodiment of the present invention;

FIG. 3 is a cross-sectional view of the electronically controlled valvetrain shown in FIG. 1;

FIG. 4 is a schematic structural view of the electronically controlled valvetrain of FIG. 1 with the housing removed;

fig. 5 is a schematic diagram of the connection of the motor and the planetary roller screw and the internal structure of the planetary roller screw.

In fig. 1:

1', valve 2', valve spring 3', camshaft 4' and timing chain wheel

In fig. 2 to 5:

1. valve 2, valve spring 3, shell 31, slideway 32, connecting column 4, motor 5, planetary roller screw 51, screw 52, roller 53, nut 54, flange 55, elastic retainer 56, slide block 6, push rod 7, press block 8, screw rod support 9, bearing part 10 and motor controller

Detailed Description

In order that those skilled in the art will better understand the disclosure, the invention will be described in further detail with reference to the accompanying drawings and specific embodiments.

In this document, terms such as "upper, lower, left, right" and the like are established based on positional relationships shown in the drawings, and the corresponding positional relationships may vary depending on the drawings, and therefore, they are not to be construed as absolute limitations on the scope of protection; moreover, relational terms such as "first" and "second," and the like, may be used solely to distinguish one element from another element having the same name, without necessarily requiring or implying any actual such relationship or order between such elements.

Referring to fig. 2, fig. 3 and fig. 4, fig. 2 is a schematic structural diagram of an electrically controlled valve mechanism according to an embodiment of the present invention; FIG. 3 is a cross-sectional view of the electronically controlled valvetrain shown in FIG. 1; fig. 4 is a schematic structural diagram of the electronically controlled valve mechanism shown in fig. 1 with the housing removed.

The valve mechanism provided by the embodiment is an electric control valve mechanism controlled by a motor, the action of each valve or each group of valves of the engine is driven by the motor, components such as a timing chain wheel and a cam shaft can be omitted, the problems that the traditional valve mechanism is narrow in adjusting range and cannot change the valve lift range and the like can be well solved, and therefore the performance of the engine is remarkably improved.

As shown in the figure, the valve mechanism mainly comprises a valve 1, a valve driving mechanism, a valve spring 2 for providing a restoring force for the valve and other components, wherein the valve driving mechanism is mainly formed by assembling a shell 3, a motor 4, a planetary roller screw 5, a push rod 6 and other components which are sequentially and axially arranged in the shell 3, the shell 3 is generally cylindrical, the upper end and the lower end of the shell are closed, a through hole is formed in the lower end of the shell, the lower end of the push rod 6 penetrates through the through hole to extend outwards for a certain distance and can do telescopic motion in the through hole so as to push the valve 1 to move downwards.

The motor 4 with stator and rotor is fixed in the shell 3, the main parts of the planetary roller screw 5 are screw 51, rollers 52 which are arranged and distributed along the circumference with the screw 51 as the center, nuts 53 which are arranged on the periphery of the rollers 52, a flange 54 and an elastic retainer ring 55, the rollers 52 are engaged with the screw 51 for transmission, the nuts 53 are engaged with the rollers 52 for transmission, the heads of the two ends of each roller 52 are arranged in the end retainer ring holes of the flange 54 through the cylindrical optical axis to keep the equal distance between the rollers 52, the flange 54 is arranged in the nut 53 which is in the shape of a sleeve in a floating way and is axially fixed through the elastic retainer ring 55.

The power output shaft of the motor 4 is connected with the screw 51 of the planetary roller screw 5, the nut 53 of the planetary roller screw 5 is connected with the push rod 6 by riveting or threaded connection, and a guide mechanism is arranged between the nut 53 and the shell 3, the guide mechanism is formed by a left slide block 56 and a right slide block 56 which are arranged on the outer surface of the nut 53 and an axial slide way 31 which is arranged on the inner surface of the shell 3, the left slide block 56 and the right slide block 56 are respectively cylindrical pins with short size, and the two cylindrical pins respectively extend into the slide way 31 and then are in axial sliding fit with the slide way 31 through the cylindrical. Thus, when the lead screw 51 is rotated, the nut 53 will move axially up or down the slideway 31 without rotating with the lead screw 51.

The lower end of the push rod 6 extends out of the shell 3 and is supported on the valve 1, and when the push rod works, the torque of the motor 4 is converted into a force in a linear direction through the planetary roller screw 5, so that the valve 1 is pushed to open and close.

Of course, the guiding mechanism can be designed into other forms besides the form of the sliding block and the sliding way. For example, providing an axial slide on the outer surface of the nut 53 to slidingly engage a slide on the inner wall of the housing 3, or interchanging the position of the slide and the slide, etc., may be used to achieve the objectives of the present invention, as long as the requirements of limiting circumferential rotation of the nut and guiding axial movement of the nut are met.

The valves shown in the figure are double valves, namely the inlet valve or the exhaust valve of the same cylinder is provided with two valves, and the axes of the motor 4, the planetary roller screw 5 and the push rod 6 of the valve are parallel to the axis of the valve 1; the upper end fixedly connected with briquetting 7 of valve 1, the both ends of briquetting 7 respectively with the upper end fixed connection of two valves 1, a through-hole has been seted up to the centre of briquetting 7, the lower extreme of push rod 6 stretches out casing 3, during the through-hole of briquetting 7 was inserted to its terminal necking down position, supported on briquetting 7 through the step position to on distributing two valves 1 with thrust is average, and guarantee that the relative position of push rod 6 and briquetting 7 remains stable throughout.

It is understood that the electronically controlled valvetrain provided by the present invention may be single or multiple valves in addition to dual valves. If the electrically controlled valve mechanism is a single valve, the axes of the motor 4, the planetary roller screw 5 and the push rod 6 can coincide with the axis of the valve 1, the lower end of the push rod 6 extends out of the shell 3 and is directly supported at the upper end of the valve 1, if the electrically controlled valve mechanism is a multi-valve, a structure similar to that of a double-valve can be adopted, and the push rod 6 pushes the valve 1 to act through the press block 7.

In order to ensure the smooth running of the planetary roller screw, a screw support 8 is additionally arranged at a proper position in the housing 3 to support the screw 51 for rotation, in the embodiment, the screw support 8 is a disc-shaped member fixed in the housing 3 and located between the motor 4 and the planetary roller screw 5, an axial through hole is arranged in the middle of the disc-shaped member for the screw 51 to pass through, and a bearing part 9 for supporting the screw 51 for rotation is arranged in the through hole.

The motor is integrated at the afterbody has motor controller 10, and whole casing 3 is the syllogic structure, is motor controller casing, motor casing and planet roller screw casing from last to down in proper order, and two adjacent casings are equipped with the spliced pole 32 of lateral on the surface outward, have seted up axial through-hole on each spliced pole 32 respectively, and connecting pieces such as accessible bolt assemble into a complete casing with three casings.

Further, a positioning and mounting portion for fixing the housing 3 to an engine may be provided on an outer surface of the housing.

Referring to fig. 5, fig. 5 is a schematic diagram of the connection between the motor and the planetary roller screw and the internal structure of the planetary roller screw.

As shown in the figure, the roller 52 of the planetary roller screw 5 comprises a large-diameter section and a small-diameter section, wherein the large-diameter section is meshed with the screw 51, and the small-diameter section is meshed with the nut 53; the large diameter section of each roller 52 is located at the middle position thereof, the small diameter section of each roller 52 comprises a first small diameter section and a second small diameter section, and the first small diameter section and the second small diameter section are respectively located at two ends of the large diameter section; the nut 53 is provided with a first internal thread and a second internal thread which are respectively engaged with the first small diameter section and the second small diameter section, and the first internal thread and the second internal thread are spaced by a certain distance to form a structure in which half is an engaged region and the other half is a non-engaged region.

The planetary roller screw structure adopted by the actuator can adopt a common planetary roller screw or a differential planetary roller screw, and the difference is that the roller and the nut of the common planetary roller screw have thread lead angles which are the same as those of the screw, the thread lead angles of the roller and the nut of the differential planetary roller screw are zero, the transmission stroke is less than the lead screw, the transmission ratio is larger, but the transmission precision is different from that of the common planetary roller screw, and the differential planetary roller screw can be selected according to actual requirements. The differential planetary roller screw is selected in the embodiment.

The above embodiments are merely preferred embodiments of the present invention, and are not limited thereto, and on the basis of the above embodiments, various embodiments can be obtained by performing targeted adjustment according to actual needs. For example, the screw rod of the planetary roller screw and the output shaft of the motor rotor can be of an integrated structure, or the screw rod of the planetary roller screw and the output shaft of the motor rotor are of a split structure, and the middle of the screw rod of the planetary roller screw and the output shaft of the motor rotor are connected through splines or threads, and the like. This is not illustrated here, since many implementations are possible.

Compared with the prior art, the invention has the technical effects that:

1) from the variable valve timing perspective:

the opening and closing of the valve by the electric control valve mechanism are controlled by the motor, the electric control valve mechanism is not a cam of the traditional mechanism, the cam is a fixed mechanical structure, and the valve timing can be adjusted only in a very limited way.

2) From the viewpoint of variable valve lift:

the lift of the variable valve mechanism of the present invention is not fixed, and the valve lift may be increased or decreased according to the needs of the engine, resulting in an increase or decrease in the intake air amount. The valve lift of the traditional valve mechanism is fixed due to the limitation of a mechanical structure, and the valve lift is controlled by a motor, so that the valve opening can be adjusted in a stepless mode in a certain area, the driving is free from a glancing feeling, the comfort is higher, the adaptability of the valve mechanism at each rotating speed is higher, and the inflation efficiency of an engine can be improved to the maximum extent.

3) From the viewpoint of improving the possibility of ECU control:

the electric control valve structure is electrically controlled, so that the possibility of calibration control can be greatly improved.

In addition to the above electrically controlled valve mechanism, the present invention also provides an engine, which comprises a cylinder body, cylinders, and intake valves and exhaust valves corresponding to the cylinders, wherein the intake valves and the exhaust valves of the cylinders are the above electrically controlled valve mechanisms.

The invention further provides an automobile which comprises an automobile body, an engine, a gearbox and wheels in transmission connection with a power output end of the gearbox, wherein the engine is provided with the electric control valve mechanism, and other structures are referred to the prior art and are not repeated herein.

The electrically controlled valve mechanism, the engine and the automobile provided by the invention are described in detail above. The principles and embodiments of the present invention are explained herein using specific examples, which are presented only to assist in understanding the core concepts of the present invention. It should be noted that, for those skilled in the art, it is possible to make various improvements and modifications to the present invention without departing from the principle of the present invention, and those improvements and modifications also fall within the scope of the claims of the present invention.

Claims

1. The electric control valve mechanism comprises a valve (1), a valve driving mechanism and a valve spring (2) for providing a reset force for the valve (1), and is characterized in that the valve driving mechanism comprises a shell (3), and a motor (4), a planetary roller screw (5) and a push rod (6) which are sequentially and axially arranged in the shell; the planetary roller screw (5) comprises a screw (51), rollers (52) which are distributed in a circumferential arrangement mode by taking the screw as a center and a nut (53) arranged on the periphery of the rollers, wherein the rollers (52) are in meshing transmission with the screw (51), and the nut (53) is in meshing transmission with the rollers (52); the power output shaft of the motor (4) is connected with the lead screw (51), the nut (53) is connected with the push rod (6), and a guide mechanism for limiting the circumferential rotation of the nut (53) and guiding the axial movement of the nut (53) is arranged between the nut and the shell (3); the lower end of the push rod (6) extends out of the shell (3) to push the valve (1) to act; the roller (52) of the planetary roller screw (5) comprises a large-diameter section and a small-diameter section, the large-diameter section is meshed with the screw (51), and the small-diameter section is meshed with the nut (53); the large-diameter section of each roller (52) is positioned in the middle of the roller, the small-diameter section of each roller (52) comprises a first small-diameter section and a second small-diameter section, and the first small-diameter section and the second small-diameter section are respectively positioned at two ends of the large-diameter section; the nut (53) is provided with a first internal thread and a second internal thread which are respectively meshed with the first small-diameter section and the second small-diameter section, and a certain distance is reserved between the first internal thread and the second internal thread.

2. The electrically controlled valve train according to claim 1, characterized in that the valve (1) is a single valve, the axes of the motor (4), the planetary roller screw (5) and the push rod (6) coincide with the axis of the valve (1), and the lower end of the push rod (6) extends out of the housing (3) and is supported at the upper end of the valve (1).

3. The electrically controlled valve train according to claim 1, characterized in that the valves (1) are double or multi valves, the axes of the motor (4), planetary roller screw (5) and push rod (6) being parallel to the axis of the valve (1); the upper end of the valve (1) is fixedly connected with a pressing block (7), and the lower end of the push rod (6) extends out of the shell (3) and is supported on the pressing block (7).

4. Electrically controlled valve mechanism according to claim 1, characterized in that the guiding means comprise a slide (56) provided on the outer surface of the nut (53) and an axial slide (31) provided on the inner surface of the housing (3), the slide (56) being in axial sliding engagement with the slide (31).

5. Electrically controlled valve train according to claim 1, characterized by further comprising a lead screw support (8); the screw support (8) is fixed inside the shell (3) and located between the motor (4) and the planetary roller screw (5), and a bearing component (9) for supporting the screw (51) to rotate is arranged between a through hole of the screw (51) and the screw (51).

6. Electrically controlled valve mechanism according to claim 1, characterized in that the outer surface of the housing (3) is provided with a positioning mounting for fixing it to the engine.

7. Electrically controlled valve mechanism according to claim 1, characterized in that the electric motor (4) is tail-integrated with a motor controller (10).

8. An engine comprising a cylinder block, cylinders, and an intake valve and an exhaust valve corresponding to each of the cylinders, characterized in that the intake valve and the exhaust valve of each of the cylinders are the electrically controlled valve mechanism according to any one of claims 1 to 7.

9. An automobile comprising a body, an engine, a gearbox and wheels drivingly connected to a power take-off of the gearbox, wherein the engine is an engine as claimed in claim 8.