CN110094437B - Clutch displacement control hysteresis elimination method - Google Patents
Clutch displacement control hysteresis elimination method Download PDFInfo
- Publication number
- CN110094437B CN110094437B CN201910285647.6A CN201910285647A CN110094437B CN 110094437 B CN110094437 B CN 110094437B CN 201910285647 A CN201910285647 A CN 201910285647A CN 110094437 B CN110094437 B CN 110094437B
- Authority
- CN
- China
- Prior art keywords
- clutch
- separation
- piston
- electromagnetic valve
- separation point
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
- F16D48/00—External control of clutches
- F16D48/06—Control by electric or electronic means, e.g. of fluid pressure
- F16D48/066—Control of fluid pressure, e.g. using an accumulator
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16H—GEARING
- F16H61/00—Control functions within control units of change-speed- or reversing-gearings for conveying rotary motion ; Control of exclusively fluid gearing, friction gearing, gearings with endless flexible members or other particular types of gearing
- F16H61/10—Controlling shift hysteresis
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
- F16D2500/00—External control of clutches by electric or electronic means
- F16D2500/10—System to be controlled
- F16D2500/102—Actuator
- F16D2500/1028—Pneumatic
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
- F16D2500/00—External control of clutches by electric or electronic means
- F16D2500/10—System to be controlled
- F16D2500/104—Clutch
- F16D2500/10443—Clutch type
- F16D2500/1045—Friction clutch
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
- F16D2500/00—External control of clutches by electric or electronic means
- F16D2500/10—System to be controlled
- F16D2500/11—Application
- F16D2500/1107—Vehicles
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
- F16D2500/00—External control of clutches by electric or electronic means
- F16D2500/30—Signal inputs
- F16D2500/302—Signal inputs from the actuator
- F16D2500/3024—Pressure
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
- F16D2500/00—External control of clutches by electric or electronic means
- F16D2500/50—Problem to be solved by the control system
- F16D2500/501—Relating the actuator
- F16D2500/5012—Accurate determination of the clutch positions, e.g. treating the signal from the position sensor, or by using two position sensors for determination
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
- F16D2500/00—External control of clutches by electric or electronic means
- F16D2500/50—Problem to be solved by the control system
- F16D2500/502—Relating the clutch
- F16D2500/50224—Drive-off
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
- F16D2500/00—External control of clutches by electric or electronic means
- F16D2500/50—Problem to be solved by the control system
- F16D2500/512—Relating to the driver
- F16D2500/5126—Improving response to driver inputs
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
- F16D2500/00—External control of clutches by electric or electronic means
- F16D2500/70—Details about the implementation of the control system
- F16D2500/704—Output parameters from the control unit; Target parameters to be controlled
- F16D2500/70402—Actuator parameters
- F16D2500/7041—Position
Landscapes
- Engineering & Computer Science (AREA)
- General Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- Mechanical Engineering (AREA)
- Hydraulic Clutches, Magnetic Clutches, Fluid Clutches, And Fluid Joints (AREA)
Abstract
A clutch displacement control hysteresis elimination method comprises the following steps: the first step is as follows: controlling the clutch to be separated, wherein after the controller receives a clutch separation signal, the controller opens a separation electromagnetic valve to supply air to the cylinder to enable the piston to move towards a separation direction, the piston pushes the clutch to be separated through a push rod at the moment, a position sensor in the cylinder monitors the position of the piston, and the controller closes the separation electromagnetic valve until the piston reaches a pre-separation point of the clutch; the second step is that: the time lag control finishes the separation, when the piston reaches the pre-separation point of the clutch, the controller controls to open the joint electromagnetic valve to enable the piston of the air cylinder to start moving in the joint direction in a small range, the position sensor in the air cylinder monitors the position of the piston, and the controller closes the joint electromagnetic valve until the piston reaches the separation point of the clutch. Therefore, the method not only shortens the distance between the two friction disks of the clutch, but also reduces the pressure of the cylinder in advance, and effectively converts the resistance direction.
Description
Technical Field
The invention relates to a method for eliminating clutch displacement control hysteresis, which is particularly suitable for overcoming the hysteresis problem of a clutch pneumatic system.
Background
The AMT clutch of the heavy commercial vehicle is mostly driven by a pneumatic actuating mechanism, and comprises an autonomous AMT of the east wind. In the original technical scheme, in the starting and gear shifting processes, after the displacement of the control clutch reaches an expected separation point, all control electromagnetic valves are closed to keep the current state, and the reverse electromagnetic valve is opened again to carry out interface action control until the clutch is required to be connected.
The original scheme has obvious time lag characteristics, so that the displacement control delay of the clutch is large, and particularly, the starting response is slow, so that the driving feeling is poor. The reasons for the occurrence of the time lag include the following two points: 1. the pneumatic system has control time lag due to compressibility of the gas; 2. during the separation and engagement processes, the actuation principles of the systems are different, and the directions of the friction forces are opposite, so even if the clutches are displaced at the same position, the air pressure in the actuation cylinders is actually required to be inconsistent during the separation and engagement processes.
An invention patent with Chinese patent publication number CN201057467Y and publication date of 2018, 9 and 4 discloses a wet clutch pressure response hysteresis compensation method, which comprises the following steps: determining the change direction of the expected pressure of the clutch in real time according to the expected pressure of the clutch, and recording the pressure value at the moment when the k-th direction changes; before the change of the k +1 th direction, hysteresis compensation is carried out on the expected pressure of the clutch between the change of the k +1 th direction and the change of the k +1 th direction by using the recorded pressure value, although the hysteresis compensation can be carried out, the invention has the following defects:
the invention is applicable to wet clutches, and is not applicable to pneumatic clutches.
Disclosure of Invention
The invention aims to solve the problem that the hysteresis of a pneumatic clutch cannot be reduced in the prior art, and provides a method for eliminating the hysteresis of clutch displacement control.
In order to achieve the above purpose, the technical solution of the invention is as follows:
a clutch displacement control hysteresis elimination method comprises the following steps:
the first step is as follows: controlling the clutch to be separated, wherein after the controller receives a clutch separation signal, the controller opens a separation electromagnetic valve to supply air to the cylinder to enable the piston to move towards a separation direction, at the moment, the piston pushes the clutch to be separated through a push rod, a position sensor in the cylinder monitors the position of the piston, and when the piston reaches a pre-separation point of the clutch, the controller closes the separation electromagnetic valve, wherein the pre-separation point is set to be a position obtained by adding a set offset to an actual mechanical complete separation point;
the second step is that: the time lag control finishes the separation, when the piston reaches the pre-separation point of the clutch, the controller controls to open the joint electromagnetic valve to enable the piston of the air cylinder to start moving in the joint direction in a small range, the position sensor in the air cylinder monitors the position of the piston, and the controller closes the joint electromagnetic valve until the piston reaches the separation point of the clutch.
In the first step: the offset set between the separation completion point and the pre-separation point ranges from 1mm to 2.5 mm.
In the second step: the distance between the complete separation point and the actual mechanical complete separation point in the time-lag control complete separation is less than or equal to 1 mm.
And the opening degrees of the separation electromagnetic valve and the joint electromagnetic valve are controlled by PWM.
Compared with the prior art, the invention has the beneficial effects that:
1. according to the method for eliminating the clutch displacement control hysteresis, after the piston reaches the clutch pre-separation point, the piston of the cylinder is controlled to start to move in the small amplitude direction, the clutch is quickly separated before the piston reaches the clutch pre-separation point, then the gear shifting time of the gearbox is utilized, the distance between the clutch pressure plate and the driven plate is shortened, the clutch hysteresis is eliminated, the gear shifting time is fully utilized, and the time consumption of the gear shifting process is effectively shortened. Therefore, the design eliminates clutch hysteresis and shortens the gear shifting time.
2. According to the method for eliminating the clutch displacement control lag, the principle of force balance generated by the movement direction of the actuator piston is reasonably utilized at the clutch displacement separation point, so that the cylinder is decompressed in advance, and the time lag scheme of a pneumatic system is overcome; the resistance direction conversion is achieved through the accurate displacement control of the air cylinder, and the displacement is basically unchanged, so that the clutch engaging action response is accelerated. Therefore, the method not only shortens the distance between the clutch pressure plate and the driven plate, but also reduces the pressure of the cylinder in advance, and effectively switches the resistance direction.
Drawings
FIG. 1 is a timing control diagram of the present invention.
Fig. 2 is a schematic diagram of the control principle of a pneumatic actuator.
FIG. 3 is a clutch displacement versus disengagement force characteristic graph.
Detailed Description
The present invention will be described in further detail with reference to the following description and embodiments in conjunction with the accompanying drawings.
Referring to fig. 1 to 2, a clutch displacement control hysteresis elimination method includes the following steps:
the first step is as follows: controlling the clutch to be separated, wherein after the controller receives a clutch separation signal, the controller opens a separation electromagnetic valve to supply air to the cylinder to enable the piston to move towards a separation direction, at the moment, the piston pushes the clutch to be separated through a push rod, a position sensor in the cylinder monitors the position of the piston, and when the piston reaches a pre-separation point of the clutch, the controller closes the separation electromagnetic valve, wherein the pre-separation point is set to be a position obtained by adding a set offset to an actual mechanical complete separation point;
the second step is that: the time lag control finishes the separation, when the piston reaches the pre-separation point of the clutch, the controller controls to open the joint electromagnetic valve to enable the piston of the air cylinder to start moving in the joint direction in a small range, the position sensor in the air cylinder monitors the position of the piston, and the controller closes the joint electromagnetic valve until the piston reaches the separation point of the clutch.
In the first step: the offset set between the separation completion point and the pre-separation point ranges from 1mm to 2.5 mm.
In the second step: the distance between the complete separation point and the actual mechanical complete separation point in the time-lag control complete separation is less than or equal to 1 mm.
And the opening degrees of the separation electromagnetic valve and the joint electromagnetic valve are controlled by PWM.
The principle of the invention is illustrated as follows:
the clutch is characterized in that a release bearing of the clutch is in transmission fit with a power output rod of a clutch execution cylinder through a driving lever, the power output rod is fixedly connected with a piston in the clutch execution cylinder, two air inlets at two ends in the clutch execution cylinder are communicated with a release electromagnetic valve, two air outlets are communicated with a joint electromagnetic valve, and meanwhile, a displacement sensor of the piston is arranged on the clutch execution cylinder.
Referring to fig. 2: when the clutch is in a separating motion, air enters the left side of the air cylinder, the piston of the actuator moves towards a separating direction (from left to right in the figure 2) from a joint point, and in the process, the system resistance is towards the left, so that the air pressure of the air cylinder needs to overcome the resultant force of the spring force and the resistance of the diaphragm of the clutch, namely the pressure of the air cylinder acting on the piston is greater than or equal to the resultant force of the diaphragm spring and the system resistance. And when the air pressure of the air cylinder is in a state of overcoming the resultant force of the diaphragm spring and the friction force, namely the pressure of the air cylinder acting on the piston is equal to the resultant force of the diaphragm spring and the friction force. After the clutch is separated, the method adds the control of a time lag overcoming stage, in the stage, the left side of the cylinder exhausts air, the clutch is slightly actuated to start to move towards the engaging direction (from right to left in figure 2), the system resistance is started to be converted into the separating direction (from right to right in figure 2), at the moment, the air pressure and the resistance of the cylinder are in the same direction, the spring force of the diaphragm is overcome together, namely the pressure of the air cylinder acting on the piston is equal to the force of the diaphragm spring minus the friction resistance. Therefore, after the clutch is disengaged, under the condition that the disengagement displacement is basically unchanged, the pressure of the cylinder is reduced in advance, and the response of the piston to move towards the engagement direction is accelerated. By the method, the response of each start can be obviously accelerated through the analysis of actual test data, and meanwhile, the cost of other objects is not increased.
Referring to fig. 3: FIG. 3 is a characteristic curve diagram of clutch displacement and separating force, after the clutch is installed, it can only move in the actual displacement range of the clutch, when the clutch moves to the separating direction, the relation between the stress and the displacement is the stress curve of the clutch separating direction, when the clutch moves to the engaging direction, the relation between the stress and the displacement is the stress curve of the clutch engaging direction, during the separating and engaging process, the system has different actuation principles, during the separating process, the clutch is pushed to move to the separating direction by overcoming the spring force of the diaphragm and the resultant force of the system resistance by the air pressure of the actuating cylinder; in the process of jointing, the resultant force of air pressure of the actuating cylinder and the resistance force of the friction force needs to be overcome by the spring force of the membrane.
It can thus be seen that: the friction force direction is opposite during the separation and the engagement, even if the clutch is displaced at the same position, the air pressure in the actuating cylinder is not consistent during the separation and the engagement, and the air pressure in the cylinder is required to be smaller than the separation direction during the engagement.
Example 1:
a clutch displacement control hysteresis elimination method comprises the following steps:
the first step is as follows: controlling the clutch to be separated, wherein after the controller receives a clutch separation signal, the controller opens a separation electromagnetic valve to supply air to the cylinder to enable the piston to move towards a separation direction, at the moment, the piston pushes the clutch to be separated through a push rod, a position sensor in the cylinder monitors the position of the piston, and when the piston reaches a pre-separation point of the clutch, the controller closes the separation electromagnetic valve, wherein the pre-separation point is set to be a position obtained by adding a set offset to an actual mechanical complete separation point;
the second step is that: the time lag control finishes the separation, when the piston reaches the pre-separation point of the clutch, the controller controls to open the joint electromagnetic valve to enable the piston of the air cylinder to start moving in the joint direction in a small range, the position sensor in the air cylinder monitors the position of the piston, and the controller closes the joint electromagnetic valve until the piston reaches the separation point of the clutch.
Example 2:
example 2 is substantially the same as example 1 except that:
in the first step: the value range of the set offset between the separation completion point and the pre-separation point is 1mm-2.5 mm; in the second step: the distance between the complete separation point and the actual mechanical complete separation point in the time-lag control complete separation is less than or equal to 1 mm.
Example 3:
example 3 is substantially the same as example 2 except that:
and the opening degrees of the separation electromagnetic valve and the joint electromagnetic valve are controlled by PWM.
Claims (4)
1. A clutch displacement control hysteresis elimination method is characterized in that: the method comprises the following steps:
the first step is as follows: controlling the clutch to be separated, wherein after the controller receives a clutch separation signal, the controller opens a separation electromagnetic valve to supply air to the cylinder to enable the piston to move towards a separation direction, at the moment, the piston pushes the clutch to be separated through a push rod, a position sensor in the cylinder monitors the position of the piston, and when the piston reaches a pre-separation point of the clutch, the controller closes the separation electromagnetic valve, wherein the pre-separation point is set to be a position obtained by adding a set offset to an actual mechanical complete separation point;
the second step is that: the time lag control finishes the separation, when the piston reaches the pre-separation point of the clutch, the controller controls to open the joint electromagnetic valve to enable the piston of the air cylinder to start moving in the joint direction in a small range, the position sensor in the air cylinder monitors the position of the piston, and the controller closes the joint electromagnetic valve until the piston reaches the separation point of the clutch.
2. The clutch displacement control hysteresis elimination method of claim 1, wherein:
in the first step: the offset set between the separation completion point and the pre-separation point ranges from 1mm to 2.5 mm.
3. The clutch displacement control hysteresis elimination method of claim 1, wherein:
in the second step: the distance between the complete separation point and the actual mechanical complete separation point in the time-lag control complete separation is less than or equal to 1 mm.
4. The clutch displacement control hysteresis elimination method of claim 1, wherein:
and the opening degrees of the separation electromagnetic valve and the joint electromagnetic valve are controlled by PWM.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910285647.6A CN110094437B (en) | 2019-04-10 | 2019-04-10 | Clutch displacement control hysteresis elimination method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910285647.6A CN110094437B (en) | 2019-04-10 | 2019-04-10 | Clutch displacement control hysteresis elimination method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN110094437A CN110094437A (en) | 2019-08-06 |
| CN110094437B true CN110094437B (en) | 2020-07-28 |
Family
ID=67444612
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910285647.6A Active CN110094437B (en) | 2019-04-10 | 2019-04-10 | Clutch displacement control hysteresis elimination method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN110094437B (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN113417951A (en) * | 2021-06-17 | 2021-09-21 | 潍柴动力股份有限公司 | Control method and control device for clutch separation and readable storage medium |
| CN114151468B (en) * | 2021-12-01 | 2024-03-26 | 中国第一汽车股份有限公司 | Clutch hysteresis model construction method, control method, device, equipment and medium |
| CN115388165A (en) * | 2022-06-20 | 2022-11-25 | 中国第一汽车股份有限公司 | Pressing force hysteresis compensation method and device for clutch and storage medium |
Family Cites Families (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP4520845B2 (en) * | 2004-12-27 | 2010-08-11 | アイシン精機株式会社 | Automatic transmission |
| CN201472163U (en) * | 2009-03-25 | 2010-05-19 | 王颜琦 | Electric clutch booster cylinder |
| CN103671618A (en) * | 2012-09-21 | 2014-03-26 | 贵州红林机械有限公司 | Clutch actuator assembly for vehicle automatic transmission |
| KR101526384B1 (en) * | 2013-03-26 | 2015-06-05 | 현대자동차 주식회사 | Engine clutch control system for hybrid vehicle and method thereof |
| CN103629341B (en) * | 2013-12-13 | 2016-03-02 | 安徽江淮汽车股份有限公司 | A kind of wet-type double-clutch automatic speed-change case Characteristics of Solenoid Valve curve compensation method |
| CN108488254B (en) * | 2018-03-12 | 2019-07-26 | 中国第一汽车股份有限公司 | Wet clutch pressure response hysteresis compensation method |
-
2019
- 2019-04-10 CN CN201910285647.6A patent/CN110094437B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN110094437A (en) | 2019-08-06 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN110094437B (en) | Clutch displacement control hysteresis elimination method | |
| US8118708B2 (en) | Method for controlling an automated friction clutch | |
| KR100334736B1 (en) | Actuator system for vehicular automated clutches with electric motor actuator and pressurized fluid override | |
| CN104315138B (en) | A kind of control method of dual-clutch transmission gear shifting actuating mechanism | |
| US7137495B2 (en) | Drivetrain | |
| KR100331205B1 (en) | Control Method and Device for Pneumatic Clutch | |
| US8960400B2 (en) | Clutch operating device | |
| CN112610689B (en) | Electric control pneumatic gear-shifting control method, system and vehicle | |
| CN201953857U (en) | Automatic clutch control mechanism | |
| US20080196989A1 (en) | Drive Train of a Motor Vehicle and Method For Controlling an Automated Engine Clutch | |
| CN204061649U (en) | Electro-pneumatic clutch actuator | |
| CN113417951A (en) | Control method and control device for clutch separation and readable storage medium | |
| CN106050983B (en) | Method for operating an actuator for operating an automated friction clutch | |
| US9523377B2 (en) | Method for controlling an actuator | |
| JP2006226316A (en) | Automobile controller and control method | |
| US8585545B2 (en) | Method of controlling an electro-actuated clutch for determining the closing position | |
| US2713850A (en) | Fluid servo-motors | |
| US7306544B2 (en) | Automatic transmission, control apparatus and control system | |
| US20210025463A1 (en) | Clutch control device | |
| CN109469689B (en) | Stepping motor type automobile clutch | |
| JPH09166160A (en) | Clutch control device | |
| WO2014190987A1 (en) | Clutch actuation system | |
| KR20050118397A (en) | Vacuum pressure production device of brake booster | |
| US4860868A (en) | Air pressure control valve of an air clutch | |
| CN211901378U (en) | Electronic pneumatic clutch actuating mechanism and electronic pneumatic clutch actuating system |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |