CN113983035A - Hydraulic control system of multispeed oil cylinder - Google Patents
Hydraulic control system of multispeed oil cylinder Download PDFInfo
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- CN113983035A CN113983035A CN202111116638.8A CN202111116638A CN113983035A CN 113983035 A CN113983035 A CN 113983035A CN 202111116638 A CN202111116638 A CN 202111116638A CN 113983035 A CN113983035 A CN 113983035A
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- 238000006073 displacement reaction Methods 0.000 claims description 12
- 239000003921 oil Substances 0.000 description 347
- 239000010720 hydraulic oil Substances 0.000 description 76
- 230000006835 compression Effects 0.000 description 2
- 238000007906 compression Methods 0.000 description 2
- 239000007788 liquid Substances 0.000 description 2
- 238000005086 pumping Methods 0.000 description 2
- 230000009471 action Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004044 response Effects 0.000 description 1
- 239000013589 supplement Substances 0.000 description 1
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B21/00—Common features of fluid actuator systems; Fluid-pressure actuator systems or details thereof, not covered by any other group of this subclass
- F15B21/08—Servomotor systems incorporating electrically operated control means
- F15B21/087—Control strategy, e.g. with block diagram
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B1/00—Installations or systems with accumulators; Supply reservoir or sump assemblies
- F15B1/02—Installations or systems with accumulators
- F15B1/024—Installations or systems with accumulators used as a supplementary power source, e.g. to store energy in idle periods to balance pump load
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B11/00—Servomotor systems without provision for follow-up action; Circuits therefor
- F15B11/02—Systems essentially incorporating special features for controlling the speed or actuating force of an output member
- F15B11/04—Systems essentially incorporating special features for controlling the speed or actuating force of an output member for controlling the speed
- F15B11/042—Systems essentially incorporating special features for controlling the speed or actuating force of an output member for controlling the speed by means in the feed line, i.e. "meter in"
- F15B11/0423—Systems essentially incorporating special features for controlling the speed or actuating force of an output member for controlling the speed by means in the feed line, i.e. "meter in" by controlling pump output or bypass, other than to maintain constant speed
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
- F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
- F15B13/00—Details of servomotor systems ; Valves for servomotor systems
- F15B13/02—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors
- F15B13/04—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors for use with a single servomotor
- F15B13/0401—Valve members; Fluid interconnections therefor
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- Physics & Mathematics (AREA)
- Fluid Mechanics (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- Fluid-Pressure Circuits (AREA)
Abstract
The utility model provides a hydraulic control system of multispeed hydro-cylinder belongs to the hydraulic control field. The hydraulic control system comprises a power output unit, a speed control unit and an execution oil cylinder. The speed control unit comprises a first hydraulic control reversing valve, a proportional reversing valve, a second hydraulic control reversing valve and an electromagnetic reversing valve, an oil outlet of the first hydraulic control reversing valve is communicated with a rod cavity of the execution oil cylinder, an oil inlet of the proportional reversing valve is communicated with an oil outlet of the power output unit, a working oil port of the proportional reversing valve is communicated with a rodless cavity of the execution oil cylinder and a control oil port of the first hydraulic control reversing valve, and an oil outlet of the proportional reversing valve is communicated with an oil inlet of the power output unit. An oil inlet of the second hydraulic control reversing valve is communicated with a rod cavity of the execution oil cylinder. The hydraulic control system can control the long-stroke oil cylinder to complete preset working conditions at various speeds.
Description
Technical Field
The disclosure belongs to the technical field of hydraulic control, and particularly relates to a hydraulic control system of a multi-speed oil cylinder.
Background
In the field of marine machinery, disc spring type hydraulic brakes are often used for braking some sports equipment. The disc spring type hydraulic brake comprises a brake pad, a brake disc, a plurality of disc springs and the like. When the brake is not needed, the disc spring is compressed through the oil cylinder, so that the disc spring drives the brake disc to move, and a gap exists between the brake disc and the brake pad. When the brake is needed, the oil cylinder releases pressure, and the brake disc is rapidly jointed with the brake disc under the action of the disc spring.
In the related technology, the movement of the oil cylinder is controlled by combining the proportional directional valve with the power output unit, and when the oil cylinder is required to push the disc spring, hydraulic oil enters the proportional directional valve through the power output unit and then enters the oil cylinder. The oil cylinder is driven to move at a constant speed through the proportional reversing valve, and then the compression movement of the disc spring is realized.
However, since the disc spring is an elastic element, when the disc spring is pushed and pressed, as the compression amount of the disc spring increases, the stroke of the cylinder also increases, and correspondingly, the load also increases. If the cylinder is moved at a constant speed, the time for the cylinder to move to the predetermined position is relatively long, which seriously affects the response speed of the brake.
Disclosure of Invention
The disclosed embodiment provides a hydraulic control system of a multi-speed oil cylinder, which can control a long-stroke oil cylinder to complete preset working conditions at various speeds. The technical scheme is as follows:
the embodiment of the disclosure provides a hydraulic control system of a multi-speed oil cylinder, which comprises a power output unit, a speed control unit and an execution oil cylinder;
the speed control unit comprises a first hydraulic control reversing valve, a proportional reversing valve and a second hydraulic control reversing valve, and the spring pressure value of the first hydraulic control reversing valve is smaller than that of the second hydraulic control reversing valve;
a first oil port of the first hydraulic control reversing valve is communicated with an oil outlet of the power output unit, a second oil port of the first hydraulic control reversing valve is communicated with a rod cavity of the execution oil cylinder, and a third oil port of the first hydraulic control reversing valve is communicated with an oil inlet of the power output unit;
an oil inlet of the proportional reversing valve is communicated with an oil outlet of the power output unit, a working oil port of the proportional reversing valve is communicated with a rodless cavity of the execution oil cylinder and a control oil port of the first hydraulic control reversing valve, and an oil outlet of the proportional reversing valve is communicated with an oil inlet of the power output unit;
the first oil port of the second hydraulic control reversing valve is communicated with the rod cavity of the execution oil cylinder, the second oil port of the second hydraulic control reversing valve is communicated with the oil inlet of the proportional reversing valve, the third oil port of the second hydraulic control reversing valve is communicated with the oil inlet of the power output unit, and the control oil port of the second hydraulic control reversing valve is communicated with the rod-free cavity of the execution oil cylinder.
In yet another implementation of the present disclosure, the speed control unit further comprises a solenoid directional valve;
the first oil port of the electromagnetic directional valve is communicated with the oil outlet of the proportional directional valve, the second oil port of the electromagnetic directional valve is communicated with the oil inlet of the power output unit, and the third oil port of the electromagnetic directional valve is communicated with the oil inlet of the proportional directional valve.
In yet another implementation of the present disclosure, the speed control unit further includes an overflow valve;
the oil inlet of the overflow valve is communicated with the oil inlet of the proportional reversing valve, the oil outlet of the overflow valve is communicated with the oil outlet of the proportional reversing valve, and the control oil of the overflow valve is communicated with the oil inlet of the overflow valve.
In yet another implementation of the present disclosure, the speed control unit further comprises an accumulator;
and a working oil port of the energy accumulator is communicated with an oil inlet of the proportional reversing valve.
In yet another implementation of the present disclosure, the speed control unit further includes a first one-way valve;
an oil inlet of the first one-way valve is communicated with an oil outlet of the power output unit, and an oil outlet of the first one-way valve is communicated with an oil inlet of the proportional reversing valve.
In yet another implementation of the present disclosure, the power take-off unit includes a first flow pump, a second flow pump, and an oil tank;
an oil outlet of the first flow pump is communicated with a first oil port of the first hydraulic control reversing valve, and an oil inlet of the first flow pump is communicated with the oil tank;
an oil outlet of the second flow pump is communicated with an oil inlet of the proportional reversing valve, and an oil inlet of the second flow pump is communicated with the oil tank.
In yet another implementation of the present disclosure, the output displacement of the first flow pump is less than the output displacement of the second flow pump.
In yet another implementation of the present disclosure, the power take-off unit further includes a second one-way valve;
an oil inlet of the second one-way valve is communicated with an oil outlet of the first flow pump, and an oil outlet of the second one-way valve is communicated with a first oil port of the first hydraulic control reversing valve.
In yet another implementation of the present disclosure, the power take-off unit further includes an oil cooler;
the oil cooler oil inlet is communicated with the oil outlet of the first hydraulic control reversing valve, the oil outlet of the second hydraulic control reversing valve and the oil outlet of the electromagnetic reversing valve, and the oil cooler oil outlet is communicated with the oil tank.
In yet another implementation of the present disclosure, the power take-off unit further includes a filter;
the oil inlet of the filter is communicated with the oil outlet of the oil cooler, and the oil outlet of the filter is communicated with the oil tank.
The technical scheme provided by the embodiment of the disclosure has the following beneficial effects:
when the hydraulic control system provided by the embodiment of the disclosure is used for driving the execution oil cylinder, firstly, the power output unit is started, so that hydraulic oil output by the power output unit enters the first hydraulic control reversing valve and the proportional reversing valve respectively.
When the brake of the disc spring type hydraulic brake needs to be released through a hydraulic control system, a piston rod of the actuating oil cylinder needs to be driven to extend out. Aiming at the proportional reversing valve, a valve core of the proportional reversing valve is in a right position after moving left, and an oil inlet in the proportional reversing valve is communicated with a working oil port. When the hydraulic oil enters the proportional reversing valve, the hydraulic oil enters the rodless cavity of the execution oil cylinder from the working oil port of the proportional reversing valve, and the piston rod of the execution oil cylinder is pushed to extend out. Meanwhile, the valve core of the first hydraulic control reversing valve is positioned at the lower position, and the first oil port and the second oil port of the first hydraulic control reversing valve are communicated. And hydraulic oil enters the first hydraulic control reversing valve through a first oil port of the first hydraulic control reversing valve. When the hydraulic oil enters the first hydraulic control reversing valve, the hydraulic oil is output from the second oil port of the first hydraulic control reversing valve, and enters the second hydraulic control reversing valve together with the hydraulic oil in the rod cavity of the execution oil cylinder through the first oil port of the second hydraulic control reversing valve. Meanwhile, the valve core of the second hydraulic control reversing valve is positioned at the right position, and the first oil port and the second oil port of the second hydraulic control reversing valve are communicated. When the hydraulic oil enters the second hydraulic control reversing valve, the hydraulic oil is output from a second oil port of the second hydraulic control reversing valve, enters the proportional reversing valve through an oil inlet of the proportional reversing valve, is further output to a rodless cavity of the execution oil cylinder, forms a differential circuit, the execution oil cylinder moves downwards in three steps of descending and high speed, and at the moment, a piston rod of the execution oil cylinder is driven to extend out at the fastest speed (three steps of high speed).
When the load of the execution oil cylinder exceeds the spring pressure value of the first hydraulic control reversing valve, the valve core of the first hydraulic control reversing valve moves downwards and is positioned at the upper position, and the third oil port of the first hydraulic control reversing valve is communicated with the first oil port. The hydraulic oil entering the first hydraulic control reversing valve through the first oil port of the first hydraulic control reversing valve does not enter the second hydraulic control reversing valve any more, but flows back to the power output unit through the third oil port of the first hydraulic control reversing valve. That is, under this condition, compared with the above descending high-speed third-gear condition, the oil supply of the power output unit through the first pilot-controlled directional valve is lacked in the rodless cavity of the actuating cylinder, so that the piston rod of the actuating cylinder is driven to extend out at a normal speed (high-speed second gear).
When the load of the execution oil cylinder continues to increase and exceeds the spring pressure value of the second hydraulic control reversing valve, the valve core of the second hydraulic control reversing valve moves to the right and is in a left position, and the third oil port of the second hydraulic control reversing valve is communicated with the first oil port. After the hydraulic oil in the rod cavity of the execution oil cylinder enters the second hydraulic control reversing valve through the first oil port of the second hydraulic control reversing valve, the hydraulic oil does not flow back to the rodless cavity of the execution oil cylinder, but flows back to the power output unit through the third oil port of the second hydraulic control reversing valve. The execution oil cylinder descends at a high speed by one gear. That is, in this operating mode, compared to the above-mentioned descending high-speed second-gear operating mode, the oil supply of the hydraulic oil in the rod-containing cavity of the actuating cylinder is lacked in the rod-free cavity of the actuating cylinder, so that the piston rod of the actuating cylinder is driven to extend at a normal speed (high-speed first-gear).
When the disc spring type hydraulic brake needs to be driven to brake through a hydraulic control system, the piston rod of the execution oil cylinder needs to retract. And aiming at the proportional reversing valve, a valve core of the proportional reversing valve is positioned at a left position after moving to the right, and an oil outlet in the proportional reversing valve is communicated with a working oil port. And hydraulic oil in a rodless cavity of the execution oil cylinder flows to an oil outlet in the proportional reversing valve through a working oil port of the proportional reversing valve and flows back to the power output unit, and the pressure of the execution oil cylinder is unloaded. Meanwhile, hydraulic oil output by the power output unit enters the second hydraulic control reversing valve and the first hydraulic control reversing valve. After the hydraulic oil enters the second hydraulic control reversing valve, the valve core of the second hydraulic control reversing valve is located at the right position, and a second oil port of the second hydraulic control reversing valve is communicated with the first oil port. When the hydraulic oil enters the second hydraulic control reversing valve, the hydraulic oil is output from a first oil port of the second hydraulic control reversing valve and enters a rod cavity of the execution oil cylinder, and a piston rod of the execution oil cylinder is pushed to retract rapidly. When the hydraulic oil enters the first hydraulic control reversing valve, the valve core of the first hydraulic control reversing valve is in the lower position, and the hydraulic oil is output from the second oil port of the first hydraulic control reversing valve, enters the rod cavity of the execution oil cylinder and pushes the piston rod of the execution oil cylinder to retract quickly.
Drawings
In order to more clearly illustrate the technical solutions in the embodiments of the present disclosure, the drawings needed to be used in the description of the embodiments are briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present disclosure, and it is obvious for those skilled in the art to obtain other drawings based on the drawings without creative efforts.
FIG. 1 is a schematic diagram of a hydraulic control system for a multi-speed cylinder provided by an embodiment of the present disclosure.
The symbols in the drawings represent the following meanings:
1. a power output unit; 11. a first flow pump; 12. a second flow pump; 13. an oil tank; 14. a second one-way valve; 15. an oil cooler; 16. a filter; 17. an electric motor;
2. a speed control unit; 21. a first hydraulic control directional control valve; 22. a proportional directional valve; 23. a second hydraulic control directional control valve; 24. an electromagnetic directional valve; 25. an overflow valve; 26. an accumulator; 27. a first check valve;
3. and an execution oil cylinder.
Detailed Description
To make the objects, technical solutions and advantages of the present disclosure more apparent, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings.
The disclosed embodiment provides a hydraulic control system of a multi-speed oil cylinder, and as shown in fig. 1, the hydraulic control system comprises a power output unit 1, a speed control unit 2 and an execution oil cylinder 3.
The speed control unit 2 comprises a first hydraulic control reversing valve 21, a proportional reversing valve 22 and a second hydraulic control reversing valve 23, and the spring pressure value of the first hydraulic control reversing valve 21 is smaller than that of the second hydraulic control reversing valve 23.
The first oil port a of the first hydraulic control directional control valve 21 is communicated with the oil outlet of the power output unit 1, the second oil port b of the first hydraulic control directional control valve 21 is communicated with the rod cavity of the execution oil cylinder 3, and the third oil port c of the first hydraulic control directional control valve 21 is communicated with the oil inlet of the power output unit 1.
An oil inlet P of the proportional reversing valve 22 is communicated with an oil outlet of the power output unit 1, a working oil port A of the proportional reversing valve 22 is communicated with a rodless cavity of the execution oil cylinder and a control oil port of the first hydraulic control reversing valve 21, and an oil outlet T of the proportional reversing valve 22 is communicated with an oil inlet of the power output unit 1.
A first oil port a of the second hydraulic control reversing valve 23 is communicated with a rod cavity of the execution oil cylinder 3, a second oil port b of the second hydraulic control reversing valve 23 is communicated with an oil inlet P of the proportional reversing valve 22, a third oil port c of the second hydraulic control reversing valve 23 is communicated with an oil inlet of the power output unit 1, and a control oil port of the second hydraulic control reversing valve 23 is communicated with a rodless cavity of the execution oil cylinder 3.
When the hydraulic control system provided by the embodiment of the present disclosure is used to drive the execution oil cylinder 3, first, the power output unit 1 is started, so that the hydraulic oil output by the power output unit 1 enters the first pilot-controlled directional control valve 21 and the proportional directional control valve 22 respectively.
When the brake of the disc spring type hydraulic brake needs to be released through a hydraulic control system, a piston rod of the actuating oil cylinder 3 needs to be driven to extend. For the proportional directional valve 22, the spool of the proportional directional valve 22 is in the right position after moving left, and the oil inlet P in the proportional directional valve 22 is communicated with the working oil port a. When the hydraulic oil enters the proportional directional valve 22, the hydraulic oil enters the rodless cavity of the execution oil cylinder 3 from the working oil port a of the proportional directional valve 22, and the piston rod of the execution oil cylinder 3 is pushed to extend. Meanwhile, the spool of the first pilot-operated directional control valve 21 is in the lower position, and the first oil port a and the second oil port b of the first pilot-operated directional control valve 21 communicate with each other. The hydraulic oil is introduced into the first pilot-operated directional valve 21 through the first oil port a of the first pilot-operated directional valve 21. When the hydraulic oil enters the first hydraulic control directional control valve 21, the hydraulic oil is output from the second oil port b of the first hydraulic control directional control valve 21, and enters the second hydraulic control directional control valve 23 together with the hydraulic oil in the rod cavity of the execution cylinder 3 through the first oil port a of the second hydraulic control directional control valve 23. Meanwhile, the spool of the second hydraulic directional control valve 23 is in the right position, and the first oil port a and the second oil port b of the second hydraulic directional control valve 23 are communicated. When the hydraulic oil enters the second hydraulic control directional control valve 23, the hydraulic oil is output from the second oil port b of the second hydraulic control directional control valve 23, enters the proportional directional control valve 22 through the oil inlet P of the proportional directional control valve 22, and is further output to the rodless cavity of the execution oil cylinder 3 to form a differential loop, the execution oil cylinder 3 moves downwards at a descending high speed three-gear, and at the moment, the piston rod of the execution oil cylinder 3 is driven to extend out at the fastest speed (at a high speed three-gear).
When the load of the execution oil cylinder 3 exceeds the spring pressure value of the first hydraulic control directional control valve 21, the valve core of the first hydraulic control directional control valve 21 moves downwards and is positioned at the upper position, and the third oil port c of the first hydraulic control directional control valve 21 is communicated with the first oil port a. The hydraulic oil introduced into the first pilot-operated directional control valve 21 through the first oil port a of the first pilot-operated directional control valve 21 is not introduced into the second pilot-operated directional control valve 23 any more, but flows back into the power output unit 1 through the third oil port c of the first pilot-operated directional control valve 21. That is, in this operating condition, compared to the above descending high-speed third-gear operating condition, the oil supply of the power output unit 1 after passing through the first pilot-controlled directional valve 21 is lacked in the rodless cavity of the actuating cylinder 3, so that the piston rod of the actuating cylinder 3 is driven to extend at a normal speed (high-speed second gear).
When the load of the execution oil cylinder 3 continues to increase and exceeds the spring pressure value of the second hydraulic control directional control valve 23, the spool of the second hydraulic control directional control valve 23 moves to the right and is at the left position, and the third oil port c of the second hydraulic control directional control valve 23 is communicated with the first oil port a. After the hydraulic oil in the rod cavity of the execution oil cylinder 3 enters the second hydraulic control directional control valve 23 through the first oil port a of the second hydraulic control directional control valve 23, the hydraulic oil does not flow back to the rodless cavity of the execution oil cylinder 3, but flows back to the power output unit 1 through the third oil port c of the second hydraulic control directional control valve 23. The actuator cylinder 3 descends at a high speed by one stage. That is, in this operating condition, compared to the above descending high-speed second-gear operating condition, the oil supply of the hydraulic oil in the rod-free chamber of the actuating cylinder 3 is lacked, so that the piston rod of the actuating cylinder 3 is driven to extend at a normal speed (high-speed first-gear).
When the disc spring type hydraulic brake needs to be driven to brake through the hydraulic control system, the piston rod of the execution oil cylinder 3 needs to retract. For the proportional directional valve 22, the spool of the proportional directional valve 22 is in the left position after moving to the right, and the oil outlet T in the proportional directional valve 22 is communicated with the working oil port a. The hydraulic oil in the rodless cavity of the execution oil cylinder 3 flows to the oil outlet T in the proportional reversing valve 22 through the working oil port A of the proportional reversing valve 22 and flows back to the power output unit 1, and the pressure of the execution oil cylinder 3 is unloaded. Meanwhile, the hydraulic oil output from the power output unit 1 enters the second pilot-operated directional control valve 23 and the first pilot-operated directional control valve 21. When the hydraulic oil enters the second hydraulic control directional control valve 23, the valve core of the second hydraulic control directional control valve 23 is in the right position, and the second oil port b of the second hydraulic control directional control valve 23 is communicated with the first oil port a. When the hydraulic oil enters the second hydraulic control directional control valve 23, the hydraulic oil is output from the first oil port a of the second hydraulic control directional control valve 23 and enters the rod cavity of the execution oil cylinder 3, and the piston rod of the execution oil cylinder 3 is pushed to retract rapidly. When the hydraulic oil enters the first hydraulic control directional control valve 21, the valve core of the first hydraulic control directional control valve 21 is in the lower position, and the hydraulic oil is output from the second oil port b of the first hydraulic control directional control valve 21, enters the rod cavity of the execution oil cylinder 3, and pushes the piston rod of the execution oil cylinder 3 to retract rapidly.
Alternatively, the power output unit 1 includes a first flow pump 11, a second flow pump 12, and a tank 13. An oil outlet of the first flow pump 11 is communicated with a first oil port a of the first hydraulic control reversing valve 21, and an oil inlet of the first flow pump 11 is communicated with the oil tank 13. The oil outlet of the second flow pump 12 is communicated with the oil inlet P of the proportional reversing valve 22, and the oil inlet of the second flow pump 12 is communicated with the oil tank 13.
In the above implementation, the oil tank 13 is used to supply the entire hydraulic control system with the power hydraulic oil. The first flow pump 11 is used for pumping power hydraulic oil for a first pilot-controlled directional control valve 21 in the hydraulic control system. The second flow pump 12 is used for pumping power hydraulic oil to a proportional directional valve 22 in the hydraulic control system so as to enable the execution cylinder 3 to be filled with hydraulic oil and finally enable the execution cylinder 3 to move.
In this embodiment, in order to enable the hydraulic oil in the oil tank 13 to meet the temperature requirement of actual use, a thermometer is usually disposed on the sidewall of the oil tank 13, so that whether the temperature in the oil tank 13 meets the actual requirement can be observed in real time through the thermometer.
For the same reason, in order to ensure that the oil in the oil tank 13 can meet the actual use requirement, a liquid level meter is usually arranged on the side wall of the oil tank 13, so that the depth of the hydraulic oil in the oil tank 13 can be observed in real time through the liquid level meter, and the volume of the hydraulic oil in the oil tank 13 is determined.
Optionally, the power output unit 1 further includes an electric motor 17, and the electric motor 17 is used to drive the first flow pump 11 and the second flow pump 12.
The motor 17 is used to drive the first flow pump 11 and the second flow pump 12 to rotate.
The first and second flow pumps 11, 12 are illustratively fixed displacement pumps.
The first flow pump 11 and the second flow pump 12 are set as fixed displacement pumps, so that output flows of the first flow pump 11 and the second flow pump 12 are constant under the condition that the rotating speeds of the first flow pump 11 and the second flow pump 12 are constant, that is, after the rotating speeds of the first flow pump 11 and the second flow pump 12 are selected, the corresponding output flows cannot be changed, the output flows of the first flow pump 11 and the second flow pump 12 cannot be changed under the condition that the rotating speeds of the first flow pump 11 and the second flow pump 12 are constant, and further, the movement stability of the execution oil cylinder 3 is ensured.
Alternatively, the output displacement of the first flow pump 11 is smaller than the output displacement of the second flow pump 12.
In the implementation manner, the output displacement of the first flow pump 11 is smaller than the output displacement of the second flow pump 12, so that when the piston rod of the actuating cylinder 3 extends, hydraulic oil can be input to the proportional directional valve 22 through the large displacement of the second flow pump 12, and the piston rod of the actuating cylinder 3 can be ensured to move rapidly. The first flow pump 11 outputs a little small displacement of hydraulic oil as the extension speed of the control piston rod, and the safety and reliability of the execution oil cylinder 3 are improved.
In the present embodiment, the first flow pump 11 is a low-pressure large-flow pump, and the second flow pump 12 is a high-pressure small-flow pump.
Optionally, the power take-off unit 1 further comprises a second non return valve 14. An oil inlet a of the second check valve 14 is communicated with an oil outlet of the first flow pump 11, and an oil outlet b of the second check valve 14 is communicated with a first oil port a of the first hydraulic control directional control valve 21.
In the implementation manner, the second check valve 14 is used to limit the flow direction of an oil path between the oil outlet of the first flow pump 11 and the first port a of the first pilot-controlled directional valve 21, that is, through setting of the second check valve 14, the hydraulic oil flowing out of the oil outlet of the first flow pump 11 can only be input to the first port a of the first pilot-controlled directional valve 21 in a single direction, but cannot flow in a reverse direction, so that the safety of the hydraulic control system is improved.
Optionally, the power take-off unit 1 further comprises an oil cooler 15. An oil inlet of the oil cooler 15 is communicated with an oil outlet b of the first hydraulic control reversing valve 21, an oil outlet b of the second hydraulic control reversing valve 23 and an oil outlet b of the electromagnetic reversing valve 24, and an oil outlet of the oil cooler 15 is communicated with the oil tank 13.
In the above implementation, the oil cooler 15 is used to reduce the hydraulic oil recovered into the oil tank 13, so that the hydraulic oil flowing out from the rodless cavity in the execution oil cylinder 3 can be cooled rapidly, and the safety of the hydraulic control system is improved.
Optionally, the power output unit 1 further includes a filter 16, an oil inlet of the filter 16 is communicated with an oil outlet of the oil cooler 15, and an oil outlet of the filter 16 is communicated with the oil tank 13.
In the above implementation manner, the addition of the filter 16 can improve the use safety of the hydraulic control system, and prevent impurities from entering the oil tank 13, and then enter the whole oil circuit again under the driving of the first flow pump 11 and the second flow pump 12, without affecting the use of each valve, and meanwhile, the normal use of the execution oil cylinder 3 can also be prevented from being affected.
With continued reference to fig. 1, the speed control unit 2 optionally further comprises a solenoid directional valve 24. A first oil port a of the electromagnetic directional valve 24 is communicated with an oil outlet P of the proportional directional valve 22, a second oil port b of the electromagnetic directional valve 24 is communicated with an oil inlet of the power output unit 1, and a third oil port c of the electromagnetic directional valve 24 is communicated with an oil inlet a of the proportional directional valve 22.
In the above implementation, when the electromagnet on the left side of the proportional directional valve 22 is powered, the spool of the proportional directional valve 22 moves to the right, and the spool is in the left position. The working oil port A of the proportional reversing valve 22 is communicated with the oil outlet T. The rodless cavity of the execution oil cylinder 3 is communicated with the oil tank 13 through a proportional reversing valve 22, and the pressure in the rodless cavity of the execution oil cylinder 3 is unloaded. At this time, the hydraulic oil output by the second flow pump 12 enters the rod cavity of the execution cylinder 3 through the second pilot-controlled directional control valve 23, and the hydraulic oil output by the first flow pump 11 enters the rod cavity of the execution cylinder through the first pilot-controlled directional control valve 21, so as to push the piston rod of the execution cylinder 3 to move upwards for retraction. The execution oil cylinder 3 moves upwards by one gear.
When the electromagnet at the upper position of the electromagnetic directional valve 24 is electrified, the valve core of the electromagnetic directional valve 24 moves downwards and is positioned at the upper position, and the third oil port c of the electromagnetic directional valve 24 is communicated with the first oil port a. The hydraulic oil output by the rodless cavity of the execution oil cylinder 3 enters the electromagnetic directional valve 24 through the oil outlet T of the proportional directional valve 22. After entering the electromagnetic directional valve 24, the hydraulic oil enters the second hydraulic directional valve 23 through the third oil port c of the electromagnetic directional valve 24, and flows to the first oil port a through the second oil port b of the second hydraulic directional valve 23 together with the hydraulic oil output by the second flow pump 12, and finally enters the rod cavity of the actuating cylinder 3, and the actuating cylinder 3 moves up at the second gear higher than the first gear.
That is, the upward moving speed of the execution oil cylinder 3 can be controlled by controlling the electromagnetic directional valve 24 so as to meet different working conditions.
Optionally, the speed control unit 2 further includes an overflow valve 25, an oil inlet a of the overflow valve 25 is communicated with an oil inlet P of the proportional directional valve 22, an oil outlet b of the overflow valve 25 is communicated with an oil outlet T of the proportional directional valve 22, and control oil c of the overflow valve 25 is communicated with an oil inlet a of the overflow valve 25.
In the above implementation manner, since the oil inlet a of the overflow valve 25 is communicated with the oil inlet P of the proportional directional valve 22, and the control oil port c of the overflow valve 25 is communicated with the oil inlet a of the overflow valve 25, the pressure at the oil inlet of the overflow valve 25 is lower than the pressure in the spring cavity of the overflow valve 25, and the overflow valve 25 is not opened. When the pressure at the oil inlet in the overflow valve 25 is higher than the pressure in the spring cavity of the overflow valve 25, the overflow valve 25 is opened, so that the pressure entering the rodless cavity of the actuating cylinder 3 is not too high, and the actuating cylinder 3 overflows when being overloaded, thereby protecting the actuating cylinder 3.
Optionally, the speed control unit 2 further includes an accumulator 26, and a working oil port of the accumulator 26 is communicated with the oil inlet P of the proportional directional valve 22.
In the above implementation, the accumulator 26 is used as an auxiliary power source to supplement the flow rate of the actuating cylinder 3 required to be supplemented when descending at high speed.
Illustratively, the number of the accumulators 26 is two, the two accumulators 26 are respectively located on two sides of the oil inlet P of the proportional reversing valve 22, and oil outlets of the two accumulators 26 are communicated with the oil inlet of the proportional reversing valve 22.
Optionally, the speed control unit 2 further includes a first check valve 27, an oil inlet a of the first check valve 27 is communicated with an oil outlet of the power output unit 1, and an oil outlet b of the first check valve 27 is communicated with an oil inlet P of the proportional directional valve 22.
In the implementation manner described above, the first check valve 27 is used to limit the flow direction of the oil path between the oil outlet of the second flow pump 12 of the power output unit 1 and the oil inlet P of the proportional directional valve 22, that is, through setting of the first check valve 27, the hydraulic oil flowing out from the oil outlet of the second flow pump 12 can only be input to the oil inlet P of the proportional directional valve 22 in one direction, but cannot flow in the reverse direction, so as to improve the safety of the hydraulic control system.
In this embodiment, the proportional reversing valve 22 is a three-position, four-way proportional reversing valve. The overflow valve 25 is an electromagnetic proportional overflow valve, so that the pressure in the spring cavity of the overflow valve 25 can be automatically adjusted by adjusting the size of the inlet of the overflow valve 25, and further the pressure entering the execution oil cylinder 3 is adjusted.
Optionally, the hydraulic control system further comprises a controller, and the controller is electrically connected with the proportional directional valve 22, the electromagnetic directional valve 24 and the overflow valve 25.
In the above implementation, the controller can automatically control the operating states of the proportional directional valve 22, the electromagnetic directional valve 24, the relief valve 25, and the like, thereby improving the operating efficiency.
The following briefly introduces the working mode of the hydraulic control system provided by the embodiment of the disclosure:
when the hydraulic control system provided by the embodiment of the present disclosure is used to drive the execution oil cylinder 3, first, the power output unit 1 is started, so that the hydraulic oil output by the power output unit 1 enters the first pilot-controlled directional control valve 21 and the proportional directional control valve 22 respectively.
When the piston rod of the actuating cylinder 3 needs to be driven to extend, the hydraulic oil output by the second flow pump 12 enters the proportional directional valve 22, at this time, the valve core of the proportional directional valve 22 is in the right position, and the oil inlet P in the proportional directional valve 22 is communicated with the working oil port a. When the hydraulic oil enters the proportional directional valve 22, the hydraulic oil enters the rodless cavity of the execution oil cylinder 3 from the working oil port a of the proportional directional valve 22, and the piston rod of the execution oil cylinder 3 is pushed to rapidly extend out.
Meanwhile, the hydraulic oil output by the first flow pump 11 enters the first hydraulic control directional control valve 21, the spool of the first hydraulic control directional control valve 21 is in the lower position, the hydraulic oil passes through the first oil port a and the second oil port b of the first hydraulic control directional control valve 21 and then passes through the first oil port a of the second hydraulic control directional control valve 23 together with the hydraulic oil in the rod cavity of the execution oil cylinder 3, the spool of the second hydraulic control directional control valve 23 is in the right position, and the first oil port a and the second oil port b of the second hydraulic control directional control valve 23 are communicated. The hydraulic oil passes through the second oil port b of the second hydraulic control directional control valve 23 and then enters the proportional directional control valve 22 through the oil inlet P of the proportional directional control valve 22, and then is output to the rodless cavity of the execution oil cylinder 3 to form a differential circuit, the execution oil cylinder 3 moves downwards at a descending high speed in three gears, and at the moment, the piston rod of the execution oil cylinder 3 is driven to extend out at the fastest speed.
When the load of the execution oil cylinder 3 exceeds the spring pressure value of the first hydraulic control directional control valve 21, the spool of the first hydraulic control directional control valve 21 moves to the upper position to work, and the first oil port a and the third oil port c of the first hydraulic control directional control valve 21 are communicated. The hydraulic oil output by the first flow pump 11 flows back to the oil tank 13 after being output through the third port c of the first pilot-controlled directional control valve 21. The actuator cylinder 3 descends at the second high speed. When the pressure value of the execution oil cylinder 3 exceeds the spring pressure value of the second hydraulic control directional control valve 23, the valve core of the second hydraulic control directional control valve 23 moves to the left position, the third oil port c of the second hydraulic control directional control valve 23 is communicated with the first oil port a, hydraulic oil flowing out of the rodless cavity in the execution oil cylinder 3 flows back into the oil tank 13 again after passing through the third oil port c of the second hydraulic control directional control valve 23, and the execution oil cylinder 3 descends at a high speed by one gear.
When the piston rod of the actuating cylinder 3 needs to be driven to retract. At this time, the spool of the proportional directional valve 22 is in the left position, and the oil outlet T in the proportional directional valve 22 is communicated with the working oil port a. The rodless cavity of the execution oil cylinder 3 is communicated with the proportional reversing valve 22 through a working oil port A of the proportional reversing valve 22 and is communicated with the power output unit 1 through an oil outlet T of the proportional reversing valve 22, and pressure unloading of the rodless cavity of the execution oil cylinder 3 is achieved. The hydraulic oil output by the first flow pump 11 enters the first hydraulic control directional control valve 21, the valve core of the first hydraulic control directional control valve 21 is at the lower position, the first oil port a and the second oil port b of the first hydraulic control directional control valve 21 are communicated, and the hydraulic oil is input into the rod cavity of the execution oil cylinder 3 through the second oil port b of the first hydraulic control directional control valve 21 to push the piston rod of the execution oil cylinder 3 to move upwards for retraction. The hydraulic oil output by the second flow pump 12 enters the second hydraulic control directional control valve 23, the first oil port a and the second oil port b of the first hydraulic control directional control valve 23 are communicated, and the hydraulic oil is input into the rod cavity of the execution oil cylinder 3 through the second oil port b of the second hydraulic control directional control valve 23 to push the piston rod of the execution oil cylinder 3 to move upwards for retraction. The execution oil cylinder 3 moves upwards by one gear.
When the electromagnet at the upper position of the electromagnetic directional valve 24 is electrified, the valve core of the electromagnetic directional valve 24 moves downwards and is positioned at the upper position, and the third oil port c of the electromagnetic directional valve 24 is communicated with the first oil port a. The hydraulic oil output by the rodless cavity of the execution oil cylinder 3 enters the electromagnetic directional valve 24 through the oil outlet T of the proportional directional valve 22. After entering the electromagnetic directional valve 24, the hydraulic oil enters the second hydraulic directional valve 23 through the third oil port c of the electromagnetic directional valve 24, and flows to the first oil port a through the second oil port b of the second hydraulic directional valve 23 together with the hydraulic oil output by the second flow pump 12, and finally enters the rod cavity of the actuating cylinder 3, and the actuating cylinder 3 moves up at the second gear higher than the first gear.
The above description is intended to be exemplary only and not to limit the present disclosure, and any modification, equivalent replacement, or improvement made without departing from the spirit and scope of the present disclosure is to be considered as the same as the present disclosure.
Claims (10)
1. The hydraulic control system of the multi-speed oil cylinder is characterized by comprising a power output unit (1), a speed control unit (2) and an execution oil cylinder (3);
the speed control unit (2) comprises a first hydraulic control reversing valve (21), a proportional reversing valve (22) and a second hydraulic control reversing valve (23), and the spring pressure value of the first hydraulic control reversing valve (21) is smaller than that of the second hydraulic control reversing valve (23);
a first oil port (a) of the first hydraulic control reversing valve (21) is communicated with an oil outlet of the power output unit (1), a second oil port (b) of the first hydraulic control reversing valve (21) is communicated with a rod cavity of the execution oil cylinder (3), and a third oil port (c) of the first hydraulic control reversing valve (21) is communicated with an oil inlet of the power output unit (1);
an oil inlet (P) of the proportional reversing valve (22) is communicated with an oil outlet of the power output unit (1), a working oil port (A) of the proportional reversing valve (22) is communicated with a rodless cavity of the execution oil cylinder (3) and a control oil port of the first hydraulic control reversing valve (21), and an oil outlet (T) of the proportional reversing valve (22) is communicated with an oil inlet of the power output unit (1);
the first oil port (a) of the second hydraulic control reversing valve (23) is communicated with the rod cavity of the execution oil cylinder (3), the second oil port (b) of the second hydraulic control reversing valve (23) is communicated with the oil inlet (P) of the proportional reversing valve (22), the third oil port (c) of the second hydraulic control reversing valve (23) is communicated with the oil inlet of the power output unit (1), and the control oil port of the second hydraulic control reversing valve (23) is communicated with the rodless cavity of the execution oil cylinder (3).
2. The hydraulic control system of claim 1, wherein the speed control unit (2) further comprises a solenoid directional valve (24);
the first oil port (a) of the electromagnetic directional valve (24) is communicated with the oil outlet (T) of the proportional directional valve (22), the second oil port (b) of the electromagnetic directional valve (24) is communicated with the oil inlet of the power output unit (1), and the third oil port (c) of the electromagnetic directional valve (24) is communicated with the oil inlet (P) of the proportional directional valve (22).
3. The hydraulic control system of claim 1, characterized in that the speed control unit (2) further comprises a relief valve (25);
an oil inlet (a) of the overflow valve (25) is communicated with an oil inlet (P) of the proportional reversing valve (22), an oil outlet (b) of the overflow valve (25) is communicated with an oil outlet (T) of the proportional reversing valve (22), and control oil (c) of the overflow valve (25) is communicated with the oil inlet (a) of the overflow valve.
4. The hydraulic control system of claim 1, wherein the speed control unit (2) further comprises an accumulator (26);
and a working oil port of the energy accumulator (26) is communicated with an oil inlet (P) of the proportional reversing valve (22).
5. The hydraulic control system of claim 1, wherein the speed control unit (2) further comprises a first check valve (27);
an oil inlet (a) of the first one-way valve (27) is communicated with an oil outlet of the power output unit (1), and an oil outlet (b) of the first one-way valve (27) is communicated with an oil inlet (P) of the proportional reversing valve (22).
6. The hydraulic control system according to claim 2, characterized in that the power take-off unit (1) comprises a first flow pump (11), a second flow pump (12) and a tank (13);
an oil outlet of the first flow pump (11) is communicated with a first oil port (a) of the first hydraulic control reversing valve (21), and an oil inlet of the first flow pump (11) is communicated with the oil tank (13);
an oil outlet of the second flow pump (12) is communicated with an oil inlet (P) of the proportional reversing valve (22), and an oil inlet of the second flow pump (12) is communicated with the oil tank (13).
7. The hydraulic control system according to claim 6, characterized in that the output displacement of the first flow pump (11) is smaller than the output displacement of the second flow pump (12).
8. The hydraulic control system according to claim 6, characterized in that the power take-off unit (1) further comprises a second non-return valve (14);
an oil inlet (a) of the second one-way valve (14) is communicated with an oil outlet of the first flow pump (11), and an oil outlet (b) of the second one-way valve (14) is communicated with a first oil port (a) of the first hydraulic control reversing valve (21).
9. The hydraulic control system according to claim 6, characterized in that the power take-off unit (1) further comprises an oil cooler (15);
an oil inlet of the oil cooler (15) is communicated with an oil outlet (b) of the first hydraulic control reversing valve (21), an oil outlet (b) of the second hydraulic control reversing valve (23) and an oil outlet (b) of the electromagnetic reversing valve (24), and an oil outlet of the oil cooler (15) is communicated with the oil tank (13).
10. The hydraulic control system according to claim 9, characterized in that the power take-off unit (1) further comprises a filter (16);
an oil inlet of the filter (16) is communicated with an oil outlet (b) of the oil cooler (15), and an oil outlet of the filter (16) is communicated with the oil tank (13).
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| Application Number | Priority Date | Filing Date | Title |
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| CN202111116638.8A CN113983035A (en) | 2021-09-23 | 2021-09-23 | Hydraulic control system of multispeed oil cylinder |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202111116638.8A CN113983035A (en) | 2021-09-23 | 2021-09-23 | Hydraulic control system of multispeed oil cylinder |
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| JPH06288402A (en) * | 1993-03-31 | 1994-10-11 | Komatsu Ltd | Oil pressure passage for swirl |
| US20030145721A1 (en) * | 2002-02-04 | 2003-08-07 | Kobelco Construction Machinery Co., Ltd | Control system and method for hydraulic working machine |
| US20120031088A1 (en) * | 2009-11-18 | 2012-02-09 | Hitachi Construction Machinery Co., Ltd. | Hydraulic drive system for construction machine |
| CN105221506A (en) * | 2015-09-18 | 2016-01-06 | 徐州工业职业技术学院 | A kind of load-sensitive valve and load-sensitive hydraulic system |
| CN111692141A (en) * | 2020-04-30 | 2020-09-22 | 武汉船用机械有限责任公司 | Hydraulic system for controlling oil cylinder |
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2021
- 2021-09-23 CN CN202111116638.8A patent/CN113983035A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH06288402A (en) * | 1993-03-31 | 1994-10-11 | Komatsu Ltd | Oil pressure passage for swirl |
| US20030145721A1 (en) * | 2002-02-04 | 2003-08-07 | Kobelco Construction Machinery Co., Ltd | Control system and method for hydraulic working machine |
| US20120031088A1 (en) * | 2009-11-18 | 2012-02-09 | Hitachi Construction Machinery Co., Ltd. | Hydraulic drive system for construction machine |
| CN105221506A (en) * | 2015-09-18 | 2016-01-06 | 徐州工业职业技术学院 | A kind of load-sensitive valve and load-sensitive hydraulic system |
| CN111692141A (en) * | 2020-04-30 | 2020-09-22 | 武汉船用机械有限责任公司 | Hydraulic system for controlling oil cylinder |
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