CN112648367A - Proportional electromagnetic valve current control method for planetary gearbox of loader - Google Patents
Proportional electromagnetic valve current control method for planetary gearbox of loader Download PDFInfo
- Publication number
- CN112648367A CN112648367A CN202110187248.3A CN202110187248A CN112648367A CN 112648367 A CN112648367 A CN 112648367A CN 202110187248 A CN202110187248 A CN 202110187248A CN 112648367 A CN112648367 A CN 112648367A
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- Prior art keywords
- current
- solenoid valve
- stage
- proportional solenoid
- planetary gearbox
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- 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
- F16H61/04—Smoothing ratio shift
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- 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
- F16H61/04—Smoothing ratio shift
- F16H61/06—Smoothing ratio shift by controlling rate of change of fluid pressure
- F16H61/061—Smoothing ratio shift by controlling rate of change of fluid pressure using electric control means
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- 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
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- 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
- F16D2500/70418—Current
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- 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
- F16D2500/70422—Clutch parameters
- F16D2500/70426—Clutch slip
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- 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
- F16H61/04—Smoothing ratio shift
- F16H61/06—Smoothing ratio shift by controlling rate of change of fluid pressure
- F16H61/061—Smoothing ratio shift by controlling rate of change of fluid pressure using electric control means
- F16H2061/062—Smoothing ratio shift by controlling rate of change of fluid pressure using electric control means for controlling filling of clutches or brake servos, e.g. fill time, fill level or pressure during filling
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- Engineering & Computer Science (AREA)
- General Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- Control Of Transmission Device (AREA)
Abstract
The invention discloses a current control method for a proportional solenoid valve of a planetary gearbox of a loader, which comprises the following steps: s1, in the pre-charging stage, the control current of the proportional solenoid valve is stepped to the pre-charging current Ia, the time Ta is kept, and then the control current is reduced to the voltage Ib; s2, in the voltage building stage, controlling the current to rise to the sliding-grinding current Ic by the proportional solenoid valve; s3, in the sliding grinding stage, controlling the current to rise to the compaction current Id by the proportional solenoid valve; s4, in the compaction stage, controlling the current to rise to the maximum traction current Ie by the proportional solenoid valve; s5, in the system pressure stage, the control current of the proportional solenoid valve is stepped to a holding current If; and S6, in the holding stage, the control current of the proportional solenoid valve is kept at the holding current If. In conclusion, the proportional solenoid valve of the planetary gearbox is controlled in stages, the control current and time of corresponding points of each stage can be adjusted, the planetary gearbox can adapt to multiple working conditions, and the problems of large gear shifting impact, large abnormal sound, large box body loss and short service life of the gearbox are solved.
Description
Technical Field
The invention relates to the technical field of engineering machinery and discloses a current control method for a proportional solenoid valve of a planetary gearbox of a loader.
Background
The planetary gearbox in the common gearbox of the transmission system of the engineering mechanical loader has the advantages of simple structure, low cost and wide application, and the current domestic mainstream planetary gearbox mainly controls the on-off of the oil way of the gearbox by a mechanical switch valve so as to control the connection and disconnection of the clutch of the planetary gearbox. The planetary gearbox controls the on-off of an oil path of the gearbox through a mechanical switch valve, the switch valve is completely opened after receiving an electric signal of a handle, and the oil of the gearbox flows through the opened switch valve to build pressure. The switch valve is only responsible for opening and closing the oil circuit of the planetary gearbox, only has two fluxes of opening and closing, and applies a single pressure curve to the clutch, so that the pressure applied to the clutch cannot be adjusted in multiple sections, and therefore the gearbox has the defects of large gear shifting impact, large abnormal sound, large box body loss and short service life.
Disclosure of Invention
The invention aims to provide a proportional solenoid valve current control method for a planetary gearbox of a loader, aiming at solving the problems, and improving the gear shifting responsiveness and the multi-working-condition adaptability of the planetary gearbox.
In order to achieve the aim, the invention discloses a current control method for a proportional solenoid valve of a planetary gearbox of a loader, which comprises the following steps:
s1, in the pre-charging stage, the control current of the proportional solenoid valve is stepped to the pre-charging current Ia, the time Ta is kept, and then the control current is reduced to the voltage Ib;
s2, in the voltage building stage, the proportional solenoid valve controls the current to rise to the sliding-grinding current Ic, the curve formula is that the actual current I1= AT + B in the voltage building stage, A is a time coefficient, and B is a time current constant;
s3, in the sliding grinding stage, the proportional solenoid valve controls the current to rise to the compaction current Id, the curve formula is that the actual current I2= CT + D in the sliding grinding stage, C is a time coefficient, and D is a time current constant;
s4, in the compaction stage, controlling the current to rise to the maximum traction current Ie by the proportional solenoid valve, wherein the curve formula is that the actual current I3= ET + F in the compaction stage, E is a time coefficient, and F is a time current constant;
s5, in the system pressure stage, the control current of the proportional solenoid valve is stepped to a holding current If;
and S6, in the holding stage, the control current of the proportional solenoid valve is kept at the holding current If.
By adopting the technical scheme, the proportional electromagnetic valve of the planetary gearbox is controlled in stages, the control current and time of corresponding points in each stage can be adjusted, the planetary gearbox can adapt to multiple working conditions, and the problems of large gear shifting impact, large abnormal sound, large box body loss and short service life of the planetary gearbox are solved.
The precharge current Ia is equal to the maximum traction current Ie. Ensuring the full pre-charging.
When the values of A and B are determined, two points on the actual current of the voltage-building stage are selected, and I1 and T of the two points are substituted into the calculation to obtain the values of A and B. Two extreme positions are chosen to facilitate the detection and calculation of I1 and T at these two points.
Two points of I1= voltage-establishing current Ib and I1= sliding-grinding current Ic are selected. Two extreme positions are chosen to facilitate the detection and calculation of I1 and T at these two points.
When the values of C and D are determined, two points on the actual current of the required sliding grinding stage are selected, and I2 and T of the two points are substituted into the calculation to obtain the values of C and D. Two extreme positions are chosen to facilitate the detection and calculation of I2 and T at these two points.
Two points of I2= sliding current Ic and I2= compacting current Id are selected. Two extreme positions are chosen to facilitate the detection and calculation of I2 and T at these two points.
When determining the values of E and F, two points on the actual current of the required sliding grinding stage are selected, and I3 and T of the two points are substituted into the calculation to obtain the values of E and F. Two extreme positions are chosen to facilitate the detection and calculation of I3 and T at these two points.
Two points, I3= sliding current Id and I3= compacting current Ie, are selected. Two extreme positions are chosen to facilitate the detection and calculation of I3 and T at these two points.
In the pre-charging stage, the pre-charging current Ia =400ma, the holding time Ta =200ms, and the voltage-building current Ib =100 ma;
in the voltage building stage, the current rises to the sliding-grinding current Ic =130 ma in 300 ms;
a sliding grinding stage, wherein the time is increased to 300ms until the compaction current Id =240 ma;
the compacting phase takes 200ms to rise to a maximum traction current Ie =400 ma. The gear-shifting responsiveness and the multi-operating-condition adaptability of the planetary gearbox are improved.
Holding current If =500 ma. The gear-shifting responsiveness and the multi-operating-condition adaptability of the planetary gearbox are improved.
In conclusion, the beneficial effects of the invention are as follows: the proportional electromagnetic valve of the planetary gearbox is controlled in stages, the control current and time of corresponding points of each stage can be adjusted, the planetary gearbox can adapt to multiple working conditions, and the problems of large gear shifting impact, large abnormal sound, large box body loss and short service life of the gearbox are solved.
Drawings
FIG. 1 is a schematic diagram of a current control curve in the current control method of the proportional solenoid valve of the planetary gearbox of the loader.
Detailed Description
The invention is further described with reference to the following figures and detailed description:
in the prior art, a planetary gearbox controls the on-off of an oil path of the gearbox through a mechanical switch valve, the switch valve is completely opened after receiving a handle electric signal, and the oil of the gearbox flows through the opened switch valve to build pressure. The switch valve is only responsible for opening and closing the oil circuit of the planetary gearbox, only has two fluxes of opening and closing, and applies a single pressure curve to the clutch, so that the pressure applied to the clutch cannot be adjusted in multiple sections, and therefore the gearbox has the defects of large gear shifting impact, large abnormal sound, large box body loss and short service life.
As shown in the attached figure 1, the current control method of the proportional solenoid valve of the planetary gearbox of the loader comprises the following steps:
s1, during the pre-charging stage, the control current of the proportional solenoid valve is stepped to the pre-charging current Ia, the holding time Ta is kept, and then the voltage is reduced to the voltage-building current Ib.
Preferably, the precharge current Ia =400ma, the holding time Ta =200ms, and the voltage-building current Ib =100 ma.
In the pre-charging stage, the control current of the proportional solenoid valve is stepped to the pre-charging current Ia, the proportional solenoid valve is activated to pre-charge hydraulic oil to the clutch control component of the gearbox, subsequent actions are facilitated, after the pre-charging is finished, the control current of the proportional solenoid valve is reduced to the voltage building current Ib, and the clutch control component has certain initial pressure, so that the next operation is facilitated.
And S2, in the voltage-building stage, controlling the current to rise to the sliding-grinding current Ic by the proportional solenoid valve, wherein the curve formula is that the actual current I1= AT + B in the voltage-building stage, A is a time coefficient, and B is a time current constant.
Preferably, the voltage build-up phase takes 300ms to rise to the sliding-grinding current Ic =130 ma.
When the values of A and B are determined, two points on the actual current of the voltage-building stage are selected, and I1 and T of the two points are substituted into the calculation to obtain the values of A and B.
Specifically, two points, I1= voltage-establishing current Ib, I1= sliding-grinding current Ic, are selected. Two extreme positions are chosen to facilitate the detection and calculation of I1 and T at these two points.
The sliding-grinding current Ic value is a current value corresponding to the condition that the gearbox clutch enters the sliding-grinding state from the separation state, at the stage, the flow of the electromagnetic valve is gradually increased, the driving force borne by the gearbox clutch is increased, and finally the gearbox clutch enters the sliding-grinding state from the separation state.
S3, in the sliding grinding stage, the proportional solenoid valve controls the current to rise to the compaction current Id, the curve formula is that the actual current I2= CT + D in the sliding grinding stage, C is a time coefficient, and D is a time current constant.
Preferably, the sliding grinding stage takes 300ms to rise to the compaction current Id =240 ma.
When the values of C and D are determined, two points on the actual current of the required sliding grinding stage are selected, and I2 and T of the two points are substituted into the calculation to obtain the values of C and D.
Two points of I2= sliding current Ic and I2= compacting current Id are selected. Two extreme positions are chosen to facilitate the detection and calculation of I2 and T at these two points.
The compaction current Id value is a corresponding current value when the gearbox clutch enters a compaction state from a sliding state, at the stage, the flow of the electromagnetic valve is further gradually increased, the driving force borne by the gearbox clutch is increased, and finally the gearbox clutch enters the compaction state from the sliding state.
S4, in the compaction stage, the proportional solenoid valve controls the current to rise to the maximum traction current Ie, the curve formula is that the actual current I3= ET + F in the compaction stage, E is a time coefficient, and F is a time current constant.
Preferably, the compacting phase, takes 200ms to rise to a maximum traction current Ie =400 ma. The precharge current Ia is equal to the maximum traction current Ie. Ensuring the full pre-charging.
When determining the values of E and F, two points on the actual current of the required sliding grinding stage are selected, and I3 and T of the two points are substituted into the calculation to obtain the values of E and F.
Two points, I3= sliding current Id and I3= compacting current Ie, are selected. Two extreme positions are chosen to facilitate the detection and calculation of I3 and T at these two points.
The maximum traction current Ie value is a corresponding current value when the gearbox clutch enters the maximum traction state from the compaction state, at the stage, the flow of the electromagnetic valve is further gradually increased, the driving force borne by the gearbox clutch is increased, finally, the gearbox clutch enters the maximum traction state from the compaction state, and at the moment, the gearbox clutch is completely combined.
S5, system pressure stage, proportional solenoid valve control current step to holding current If.
Preferably, the holding current If =500 ma.
And S6, in the holding stage, the control current of the proportional solenoid valve is kept at the holding current If.
Further improve the combination pressure of gearbox clutch, guarantee that power transmission is stable.
In one embodiment of the invention, the holding current If =450ma or 550 ma.
The proportional electromagnetic valve of the planetary gearbox is controlled in stages, the control current and time of corresponding points of each stage can be adjusted, the planetary gearbox can adapt to multiple working conditions, and the problems of large gear shifting impact, large abnormal sound, large box body loss and short service life of the gearbox are solved.
The above description is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, various modifications and substitutions can be made without departing from the technical principle of the present invention, and these modifications and substitutions should also be regarded as the protection scope of the present invention.
Claims (10)
1. A current control method for a proportional solenoid valve of a planetary gearbox of a loader is characterized by comprising the following steps:
s1, in the pre-charging stage, the control current of the proportional solenoid valve is stepped to the pre-charging current Ia, the time Ta is kept, and then the control current is reduced to the voltage Ib;
s2, in the voltage building stage, the proportional solenoid valve controls the current to rise to the sliding-grinding current Ic, the curve formula is that the actual current I1= AT + B in the voltage building stage, A is a time coefficient, and B is a time current constant;
s3, in the sliding grinding stage, the proportional solenoid valve controls the current to rise to the compaction current Id, the curve formula is that the actual current I2= CT + D in the sliding grinding stage, C is a time coefficient, and D is a time current constant;
s4, in the compaction stage, controlling the current to rise to the maximum traction current Ie by the proportional solenoid valve, wherein the curve formula is that the actual current I3= ET + F in the compaction stage, E is a time coefficient, and F is a time current constant;
s5, in the system pressure stage, the control current of the proportional solenoid valve is stepped to a holding current If;
and S6, in the holding stage, the control current of the proportional solenoid valve is kept at the holding current If.
2. The method of claim 1, wherein the pre-charge current Ia is equal to the maximum traction current Ie.
3. The method for controlling the current of the proportional solenoid valve of the planetary gearbox of the loader according to claim 1, wherein when the values of A and B are determined, two points on the actual current of the required pressure buildup stage are selected, and the values of A and B are obtained by substituting I1 and T of the two points into the calculation.
4. The current control method for the proportional solenoid valve of the planetary gearbox of the loader as recited in claim 3, characterized in that two points of I1= voltage-building current Ib, I1= slip current Ic are selected.
5. The method for controlling the current of the proportional solenoid valve of the planetary gearbox of the loader according to claim 1, wherein when the values of C and D are determined, two points on the actual current of the required slip stage are selected, and the values of C and D are obtained by substituting I2 and T of the two points into the calculation.
6. The current control method for the proportional solenoid valve of the planetary gearbox of the loader as recited in claim 5, characterized in that two points of I2= slip current Ic and I2= hold-down current Id are selected.
7. The method for controlling the current of the proportional solenoid valve of the planetary gearbox of the loader according to claim 1, wherein when the values of E and F are determined, two points on the actual current of the required slip stage are selected, and the values of E and F are obtained by substituting I3 and T of the two points into the calculation.
8. The current control method for the proportional solenoid valve of the planetary gearbox of the loader as recited in claim 7, characterized in that two points of I3= slip current Id and I3= hold-down current Ie are selected.
9. The current control method for the proportional solenoid valve of the planetary gearbox of the loader as set forth in any one of claims 1 to 8, characterized in that in the pre-charging stage, the pre-charging current Ia =400ma, the holding time Ta =200ms, and the voltage-building current Ib =100 ma;
in the voltage building stage, the current rises to the sliding-grinding current Ic =130 ma in 300 ms;
a sliding grinding stage, wherein the time is increased to 300ms until the compaction current Id =240 ma;
the compacting phase takes 200ms to rise to a maximum traction current Ie =400 ma.
10. The loader planetary gearbox proportional solenoid valve current control method of any one of claims 1 to 8, characterized in that holding current If =500 ma.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110187248.3A CN112648367A (en) | 2021-02-18 | 2021-02-18 | Proportional electromagnetic valve current control method for planetary gearbox of loader |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110187248.3A CN112648367A (en) | 2021-02-18 | 2021-02-18 | Proportional electromagnetic valve current control method for planetary gearbox of loader |
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| CN112648367A true CN112648367A (en) | 2021-04-13 |
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| CN202110187248.3A Pending CN112648367A (en) | 2021-02-18 | 2021-02-18 | Proportional electromagnetic valve current control method for planetary gearbox of loader |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114046353A (en) * | 2021-12-06 | 2022-02-15 | 雷沃工程机械集团有限公司 | Control method of electric control automatic gearbox |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN109764072A (en) * | 2017-11-09 | 2019-05-17 | 雷沃重工股份有限公司 | Wet clutch and its control method, cropper |
| CN110094502A (en) * | 2019-04-26 | 2019-08-06 | 科力远混合动力技术有限公司 | The pre-oiling control method of wet clutch in hybrid power gearbox |
| CN111271443A (en) * | 2020-01-17 | 2020-06-12 | 山推工程机械股份有限公司 | Gear shifting controller and system of bulldozer |
| CN111536230A (en) * | 2020-05-12 | 2020-08-14 | 南京劲力变速器科技有限公司 | Static gear shifting control method of automatic gearbox |
| CN111536229A (en) * | 2020-05-08 | 2020-08-14 | 南京劲力变速器科技有限公司 | Gear-up control method for AT automatic transmission |
-
2021
- 2021-02-18 CN CN202110187248.3A patent/CN112648367A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109764072A (en) * | 2017-11-09 | 2019-05-17 | 雷沃重工股份有限公司 | Wet clutch and its control method, cropper |
| CN110094502A (en) * | 2019-04-26 | 2019-08-06 | 科力远混合动力技术有限公司 | The pre-oiling control method of wet clutch in hybrid power gearbox |
| CN111271443A (en) * | 2020-01-17 | 2020-06-12 | 山推工程机械股份有限公司 | Gear shifting controller and system of bulldozer |
| CN111536229A (en) * | 2020-05-08 | 2020-08-14 | 南京劲力变速器科技有限公司 | Gear-up control method for AT automatic transmission |
| CN111536230A (en) * | 2020-05-12 | 2020-08-14 | 南京劲力变速器科技有限公司 | Static gear shifting control method of automatic gearbox |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114046353A (en) * | 2021-12-06 | 2022-02-15 | 雷沃工程机械集团有限公司 | Control method of electric control automatic gearbox |
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Application publication date: 20210413 |