CN2658451Y - Digital electrohydraulic control system for metal belt type stepless speed changer - Google Patents
Digital electrohydraulic control system for metal belt type stepless speed changer Download PDFInfo
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- CN2658451Y CN2658451Y CNU2003201127793U CN200320112779U CN2658451Y CN 2658451 Y CN2658451 Y CN 2658451Y CN U2003201127793 U CNU2003201127793 U CN U2003201127793U CN 200320112779 U CN200320112779 U CN 200320112779U CN 2658451 Y CN2658451 Y CN 2658451Y
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- valve
- oil cylinder
- stepless speed
- control valve
- control system
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E10/00—Energy generation through renewable energy sources
- Y02E10/20—Hydro energy
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Abstract
The utility model relates to a digital electric-hydraulic control system for metal belt type stepless speed changer, comprising a clamp force control valve JV4, a speed ratio control valve JV5, a clutch control valve JV6, a reverse gear prohibition valve JV8, and an electric fault protective valve JV9, wherein the clamp force control valve JV4, the speed ratio control valve JV5 and the clutch control valve JV6 are connected with digital flux valves DV1, DV2, DV3 driven by a stepper motor. The reverse gear prohibition valve JV8 and the electric fault protective valve JV9 are provided with high speed switch valves EV1, EV2, an engine pitot tube, and a driving wheel pitot tube. The utility model has high control precision, better repeatability, simple structure and lower cost, which enhances the fuel economy and dynamic performance of the automobile by accurately controlling the clamping force and speed ratio of the metal strap.
Description
Technical field:
The utility model relates to a kind of metal band type stepless speed variator electrohydraulic control system, particularly relates to a kind of metal band type stepless speed variator digital electrohydraulic control system.
Background technique:
CVT (continuously variable transmission) is a kind of high-tech product, hydraulic control system is one of key technology of stepless speed variator, the CVT hydraulic control system of putting on market in 1987, and it adopts the mechanical handling mode, owing to the problem that exists is more, put on market soon just to be replaced by electronic control mode.There are the following problems for this machine hydraulic control system mode:
1) can not carry out independent control to the pressure of master/slave moving cylinder, it only can change with the aperture of fixing relation according to throttle, thereby is difficult to realize the accurate control of clamping force and speed ratio.
2) adopt Pitot tube can not accurately monitor the variation of engine speed, with the piecewise nonlinear balance and the rotating speed square pressure signal that is directly proportional of two springs, consequent error is bigger, is difficult to realize the accurate control of clamping force and speed ratio.
3) it can not be suitable for other vehicle, because as long as power train and automobile parameter change, all must change the physical dimension of control lever.
When 4) automobile stopped suddenly, metal tape may rest on neutral position arbitrarily, influenced the smoothness that automobile is started to walk next time.
Because some intrinsic defective of machine liquid control system, it can not make every performance index of automobile perform to the optimum state.The CVT product generally all adopts the electro-hydraulic control system at present.Generally adopt electromagnetic proportional valve to realize metal tape clamping force and driver Transmission Ratio Control as current C VT electrohydraulic control system, can overcome the defective of machine hydraulic control system mode.But still keeping some essential problem of solenoid valve by the hydraulic control system that electromagnetic proportional valve is formed, poor as control accuracy, be connected the special-purpose D/A interface of needs with the signal of microprocessor, quantization error and transmit noise and all influence control accuracy.
Summary of the invention:
The purpose of this utility model is to provide a kind of metal band type stepless speed variator digital electrohydraulic control system, is a kind of stepless change control system of more efficient, more reliable, more economical practicality.Owing to adopted digital stream metered valve and high-speed solenoid valve as the HYDRAULIC CONTROL SYSTEM element, adopt pulse number modulation (PNM) and pulsewidth modulation (PWM) mode to work, directly by Computer I/O interface, and do not need D/A converter.Compare with the servovalve system with Proportional valve in the past, have simple in structure, good manufacturability, an advantage such as cost is low, contamination resistance is strong, repeatability is high, reliable operation, energy consumption are little.For a kind of new way has been opened up in the application of computer in hydraulic system, also improved the task performance of hydraulic system simultaneously greatly.Because the utility model mainly is to be applied in the auto continuously variable transmission, work reliably for guaranteeing security of system, designed the electrical failure standby system in the system, when guaranteeing system's dead electricity (as power failure), automobile still can be to leave go back to maintenance station and garage than low speed.Valve is forbidden in gearshift at a high speed, prevents to commutate when high speed and reverses gear, and boundary belt and relevant transmission part are not subjected to strong mechanical shock effectively.
The technical solution of the utility model is achieved in that the metal band type stepless speed variator digital electrohydraulic control system, and stepless speed variator is by initiatively fixedly half cone wheel, initiatively movable half cone wheel, start clutch, the break that reverses gear, the break oil cylinder that reverses gear, start clutch oil cylinder, driving wheel oil cylinder, passive fixedly half cone wheel, passive movable half cone wheel, driven wheel oil cylinder etc.; Wherein be connected with stepper motor driven digital stream metered valve DV1, DV2, DV3 on clamping force control valve JV4, Transmission Ratio Control valve JV5, the clutch control valve JV6, forbid being equipped with on valve JV8 and the electrical failure Protective valve JV9 high-speed switch valve EV1, EV2 and motor Pitot tube and driving wheel Pitot tube reversing gear.Digital stream metered valve DV1 and clamping force control valve JV4, by the pulse number modulation (PNM) to stepper motor, the pressure of control stepless transmission driven wheel oil cylinder is to adapt to the variation of stepless speed variator input torque, guarantee to have enough frictional force between band and belt wheel, reliably transmitting torque.
By digital stream metered valve DV2 and Transmission Ratio Control valve JV5, in stepless speed variator driving wheel oil cylinder 7 charged pressure oil or from oil cylinder head pressure oil, change the operating pitch radius of driving pulley, the accurately variation of continuous control transmission gear ratio.
Digital stream metered valve DV3 and clutch control valve JV6, by pulse number modulation to stepper motor, pressure in the control start clutch oil cylinder 6, the joint of realizing clutch with separate, realize power between automobile balance starting fast or escape engine and the driver according to driver's operation intention.
Switch valve EV2 resets under the effect of spring force because of dead electricity, and the motor pitot pressure enters the right-hand member of error protection valve JV9, and spool is moved to the left.Motor pitot pressure oil enters into the start clutch oil cylinder as a result, the clutch combination, and automobile still can travel, thereby realizes the electrical failure protection.
Reverse gear and forbid that valve JV8 is communicated with the driving pulley pitot pressure, when the speed of a motor vehicle reaches a certain value, forbid that the spool of valve JV8 moves to right, cut off the oil circuit of clutch that reverses gear, thereby forbid reversing gear combination under high speed.
It is higher that good effect of the present utility model is to have control accuracy, and repeatability is better; Structure is more simple, and cost can be lower; By the clamping force and the speed ratio of accurate control metal tape, can improve fuel economy, the power character of automobile.
Description of drawings:
The structure principle chart of Fig. 1 stepless speed variator.
Fig. 2 structure principle chart of the present utility model.
Fig. 3 clamping force of the present utility model (line pressure) control oil hydraulic circuit.
Fig. 4 Transmission Ratio Control oil hydraulic circuit of the present utility model.
Fig. 5 start clutch of the present utility model, the break that reverses gear are controlled oil hydraulic circuit, electrical failure back-up circuit and are reversed gear and forbid the loop.
The embodiment that Fig. 6, Fig. 7 the utility model have been simplified.
Embodiment:
Below in conjunction with accompanying drawing the utility model is further described:
Metal band type stepless speed variator digital electrohydraulic control system, stepless speed variator as shown in Figure 1 are by initiatively fixedly half cone wheel 1, initiatively movable half cone wheel 2, start clutch 3, the break 4 that reverses gear, the break oil cylinder 5 that reverses gear, start clutch oil cylinder 6, driving wheel oil cylinder 7, passive fixedly half cone wheel 8, passive movable half cone wheel 9, driven wheel oil cylinder 10 etc.; As shown in Figure 2 clamping force control valve JV4, Transmission Ratio Control valve JV5, clutch control valve JV6, reverse gear and forbid that valve JV8, electrical failure Protective valve JV9 form; Wherein be connected with stepper motor driven digital stream metered valve DV1, DV2, DV3 on clamping force control valve JV4, Transmission Ratio Control valve JV5, the clutch control valve JV6, forbid being equipped with on valve JV8 and the electrical failure Protective valve JV9 high-speed switch valve EV1, EV2 and motor Pitot tube and driving wheel Pitot tube reversing gear.Digital stream metered valve DV1 and clamping force control valve JV4, by the pulse number modulation (PNM) to stepper motor, the pressure of control stepless transmission driven wheel oil cylinder is to adapt to the variation of stepless speed variator input torque, guarantee to have enough frictional force between band and belt wheel, reliably transmitting torque.
By digital stream metered valve DV2 and Transmission Ratio Control valve JV5, in stepless speed variator driving wheel oil cylinder 7 charged pressure oil or from oil cylinder head pressure oil, change the operating pitch radius of driving pulley, the accurately variation of continuous control transmission gear ratio.
Digital stream metered valve DV3 and clutch control valve JV6, by pulse number modulation to stepper motor, pressure in the control start clutch oil cylinder 6, the joint of realizing clutch with separate, realize power between automobile balance starting fast or escape engine and the driver according to driver's operation intention.
Switch valve EV2 resets under the effect of spring force because of dead electricity, and the motor pitot pressure enters the right-hand member of error protection valve JV9, and spool is moved to the left.Motor pitot pressure oil enters into the start clutch oil cylinder as a result, the clutch combination, and automobile still can travel, thereby realizes the electrical failure protection.
Reverse gear and forbid that valve JV8 is communicated with the driving pulley pitot pressure, when the speed of a motor vehicle reaches a certain value, forbid that the spool of valve JV8 moves to right, cut off the oil circuit of the clutch that reverses gear, prevent at a high speed in conjunction with reversing gear.
The control of follower oil cylinder clamping force as shown in Figures 2 and 3, the pressure oil that self-pumping comes enters into the filler opening of digital stream metered valve DV1 behind constant pressure pressure-reducing valve JV2, fixed throttle port, can change the size of restriction by control to stepper motor arteries and veins quantity, realization is to the control of follower oil cylinder working-pressure, thus the clamping force of control driven pulley.If digital stream metered valve choke area reduces, the pressure that then enters clamping force control valve JV4 increases, and overcomes spring force spool is moved to the left, and the area of meter out mouth is diminished.The result reduces the flow that flows back to fuel tank by valve JV4, and oil pump delivery pressure (line pressure) increases, and the clamping force of driven pulley also increases thereupon, and vice versa.
As the control of Fig. 2 and driving wheel Pitch radius shown in Figure 4, from the pressure oil of reduction valve JV2, the fixed orifice before digital stream metered valve DV2 flow to the filler opening of valve DV2.Control the area of two corresponding restrictions respectively by the clockwise and anticlockwise of stepper motor, change the pressure at Transmission Ratio Control valve JV5 two ends.Under the effect of pressure reduction, make the spool move left and right of Transmission Ratio Control valve JV5, realize oil-filled or oil extraction to the driving pulley oil cylinder, reach the purpose of Transmission Ratio Control.If left side restriction is connected, then the right restriction is closed, and the spool of Transmission Ratio Control valve JV5 is moved to the left, and the left side restriction of valve JV5 is opened, and the pressure oil that comes from oil pump enters into the driving pulley oil cylinder, and the driving pulley radius of clean-up increases, and speed changer rises to high gear.If left side restriction is closed, restriction is connected, and the moving direction of the spool of Transmission Ratio Control valve JV5 is with last opposite, and the spool of valve JV5 moves right.The result makes the fluid of driving pulley oil cylinder flow back to fuel tank, and the driving pulley radius of clean-up reduces, and speed changer is reduced to low gear.Because the restriction of the left and right sides can change continuously, so the speed ratio variance ratio of driver can ratio as required be regulated arbitrarily.
As Fig. 2 and start clutch shown in Figure 5 control and fault back-up circuit, when manual shift valve JV7 placed D retaining (forward gear) position, digital stream metered valve DV3 closed, and the spool of clutch control valve JV6 is moved to the left.So, enter into electrical failure Protective valve JV9 by manually operated valve JV7 from the pressure oil of reduction valve JV2.If the electrical system fault-free, the start clutch that advances engages, and automobile to overtake.And when electrical system broke down, switch valve EV2 resetted under the effect of spring force because of dead electricity, and the motor pitot pressure enters the right-hand member of error protection valve JV9, and spool is moved to the left.Motor pitot pressure oil enters into the start clutch oil cylinder as a result, the clutch combination, and automobile still can travel, thereby realizes the electrical failure protection.
Control and change to reverse gear and forbid valve as Fig. 2 and shown in Figure 5 reversing gear, when manual shift valve JV7 placed R retaining (reversing gear) position, the switch valve EV1 that reverses gear connected, and the brake engages of reversing gear realizes reverse travel.Change to mistakenly during for fear of automobile high-speed and reverse gear, this system is provided with one and reverses gear and forbid valve JV8, and it utilizes driving pulley pitot pressure (when the speed of a motor vehicle reaches a certain value) to forbid that the spool of valve JV8 moves to right, and cuts off the oil circuit of the clutch that reverses gear, and realizes changing to reverse gear forbidding.
Shown in Fig. 6,7, in Transmission Ratio Control loop and Clutch Control loop, replace the digital stream metered valve with high-speed switch valve, adopt pulse width modulation mode to realize Transmission Ratio Control and start clutch control respectively.This scheme is simple, but controlling performance is poor slightly, is applicable to the economy car of low price.
Claims (6)
1, a kind of metal band type stepless speed variator digital electrohydraulic control system, stepless speed variator comprise initiatively fixedly half cone wheel (1), initiatively movable half cone wheel (2), start clutch (3), the break that reverses gear (4), the break oil cylinder (5) that reverses gear, start clutch oil cylinder (6), driving wheel oil cylinder (7), passive fixedly half cone wheel (8), passive movable half cone wheel (9), driven wheel oil cylinder (10) etc.; It is characterized in that: be connected with stepper motor driven digital stream metered valve DV1, DV2, DV3 on the oil circuit of clamping force control valve JV4, Transmission Ratio Control valve JV5, clutch control valve JV6, forbid being equipped with on valve JV8 and the electrical failure Protective valve JV9 high-speed switch valve EV1, EV2 and holder of motor skin and the holder of driving wheel skin reversing gear.
2, according to the described metal band type stepless speed variator digital electrohydraulic control system of claim 1, it is characterized in that described digital stream metered valve DV1 and clamping force control valve JV4, by pulse number modulation PNM to stepper motor, the pressure of control stepless transmission driven wheel oil cylinder, transmitting torque.
3, according to the described metal band type stepless speed variator digital electrohydraulic control system of claim 1, it is characterized in that described Transmission Ratio Control valve JV5 is by digital stream metered valve DV2, in stepless speed variator driving wheel oil cylinder (7) charged pressure oil or from oil cylinder head pressure oil, change the operating pitch radius of driving pulley.
4, according to the described metal band type stepless speed variator digital electrohydraulic control system of claim 1, it is characterized in that described clutch control valve JV6 and digital stream metered valve DV3, by pulse number modulation to stepper motor, the pressure in the control start clutch oil cylinder (6).
5, according to the described metal band type stepless speed variator digital electrohydraulic control system of claim 1, it is characterized in that described change to reverse gear forbid that valve JV8 is the two-position three way high-speed switch valve.
6,, it is characterized in that described reversing gear forbid that valve JV8 is communicated with the driving pulley pitot pressure according to the described metal band type stepless speed variator digital electrohydraulic control system of claim 1.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNU2003201127793U CN2658451Y (en) | 2003-11-21 | 2003-11-21 | Digital electrohydraulic control system for metal belt type stepless speed changer |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNU2003201127793U CN2658451Y (en) | 2003-11-21 | 2003-11-21 | Digital electrohydraulic control system for metal belt type stepless speed changer |
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| Publication Number | Publication Date |
|---|---|
| CN2658451Y true CN2658451Y (en) | 2004-11-24 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNU2003201127793U Expired - Lifetime CN2658451Y (en) | 2003-11-21 | 2003-11-21 | Digital electrohydraulic control system for metal belt type stepless speed changer |
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| CN (1) | CN2658451Y (en) |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102812271A (en) * | 2010-03-25 | 2012-12-05 | 舍弗勒技术股份两合公司 | Hydraulic system |
| CN102840324A (en) * | 2012-08-27 | 2012-12-26 | 湘潭大学 | Electrohydraulic control system of stepless transmission with small volume and low cost |
| CN101561043B (en) * | 2008-04-16 | 2013-03-06 | 丰田自动车株式会社 | Control device for stepless speed changer, and control method |
| CN101718337B (en) * | 2009-12-22 | 2013-06-05 | 吉林大学 | Electricity-liquid integration control device for metal belt continuously variable transmission, clamp type control valve and digital pressure reduction valve |
| CN103776630A (en) * | 2014-02-13 | 2014-05-07 | 湘潭大学 | Metal band type stepless transmission sliding rate test platform |
| CN111749945A (en) * | 2020-06-29 | 2020-10-09 | 浙江大学 | Sheet type hydraulic stepping driver based on high-speed switch valve and control method thereof |
-
2003
- 2003-11-21 CN CNU2003201127793U patent/CN2658451Y/en not_active Expired - Lifetime
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101561043B (en) * | 2008-04-16 | 2013-03-06 | 丰田自动车株式会社 | Control device for stepless speed changer, and control method |
| CN101718337B (en) * | 2009-12-22 | 2013-06-05 | 吉林大学 | Electricity-liquid integration control device for metal belt continuously variable transmission, clamp type control valve and digital pressure reduction valve |
| CN102812271A (en) * | 2010-03-25 | 2012-12-05 | 舍弗勒技术股份两合公司 | Hydraulic system |
| CN102812271B (en) * | 2010-03-25 | 2016-02-10 | 舍弗勒技术股份两合公司 | Hydraulic system |
| CN102840324A (en) * | 2012-08-27 | 2012-12-26 | 湘潭大学 | Electrohydraulic control system of stepless transmission with small volume and low cost |
| CN102840324B (en) * | 2012-08-27 | 2015-03-04 | 湘潭大学 | Electrohydraulic control system of stepless transmission with small volume and low cost |
| CN103776630A (en) * | 2014-02-13 | 2014-05-07 | 湘潭大学 | Metal band type stepless transmission sliding rate test platform |
| CN103776630B (en) * | 2014-02-13 | 2016-06-15 | 湘潭大学 | Metal band type stepless speed variator slip rate testboard |
| CN111749945A (en) * | 2020-06-29 | 2020-10-09 | 浙江大学 | Sheet type hydraulic stepping driver based on high-speed switch valve and control method thereof |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| ASS | Succession or assignment of patent right |
Owner name: HUNAN RONGDA AUTOMOTIVE ELECTRON TECHNOLOGY CO., Free format text: FORMER OWNER: ZHOU YUNSHAN Effective date: 20050415 |
|
| C41 | Transfer of patent application or patent right or utility model | ||
| TR01 | Transfer of patent right |
Effective date of registration: 20050415 Address after: 410013, Hunan Changsha hi tech Industrial Development Zone, torch City, MO group, south two floor Patentee after: Hunan Rong Da Automotive Electronic Technology Co., Ltd. Address before: 130021 Jilin province city Changchun Changchun Institute of South 422 dormitory No. Patentee before: Zhou Yunshan |
|
| ASS | Succession or assignment of patent right |
Owner name: HUNAN JIANGLU-RONGDA VEHICLE TRANSMISSION LIMITED Free format text: FORMER OWNER: HUNAN RONGDA AUTOMOTIVE ELECTRON TECHNOLOGY CO., LTD. Effective date: 20060901 |
|
| C41 | Transfer of patent application or patent right or utility model | ||
| TR01 | Transfer of patent right |
Effective date of registration: 20060901 Address after: 410205, No. 8, Lu Lu, hi tech Industrial Development Zone, Hunan, Changsha Patentee after: Hunan jianglirong vehicle rotation limited liability company Address before: 410013, Hunan Changsha hi tech Industrial Development Zone, torch City, MO group, south two floor Patentee before: Hunan Rong Da Automotive Electronic Technology Co., Ltd. |
|
| C56 | Change in the name or address of the patentee |
Owner name: HUNAN JIANGLURONG VEHICLE DRIVE CO., LTD. Free format text: FORMER NAME: HUNAN JIANGLU-RONGDA VEHICLE TRANSMISSION LIMITED COMPANY |
|
| CP03 | Change of name, title or address |
Address after: No. 888, azalea Road, Changsha, Hunan, Yuelu District: 410205 Patentee after: Hunan Jianglu & Rongda Vehicle Transmission Limited Company Address before: No. 8, Lu Lu, hi tech Industrial Development Zone, Hunan, Changsha Province: 410205 Patentee before: Hunan Jianglu & Rongda Vehicle Transmission Co., Ltd. |
|
| C17 | Cessation of patent right | ||
| CX01 | Expiry of patent term |
Expiration termination date: 20131121 Granted publication date: 20041124 |