CN217107217U - Hydraulic system and vehicle - Google Patents
Hydraulic system and vehicle Download PDFInfo
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- CN217107217U CN217107217U CN202122862635.0U CN202122862635U CN217107217U CN 217107217 U CN217107217 U CN 217107217U CN 202122862635 U CN202122862635 U CN 202122862635U CN 217107217 U CN217107217 U CN 217107217U
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- 238000013016 damping Methods 0.000 abstract description 8
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Abstract
The utility model discloses a hydraulic system and a vehicle, wherein the hydraulic system comprises an engine, a gear pump, a variable cylinder, a plunger pump, a valve block and a foot valve; in the valve block, the oil inlet is communicated with the gear pump; the inlet of the first throttle valve is communicated with the oil inlet, and the outlet of the first throttle valve is communicated with the first inlet of the first reversing valve, the first inlet of the second reversing valve and the inlet of the third reversing valve; the first throttling damping inlet is communicated with the oil inlet, and the outlet is communicated with a second inlet of the first reversing valve and a second inlet of the second reversing valve; the second throttling damping inlet is communicated with the oil inlet, and the outlet is communicated with an oil supplementing port of the plunger pump; the outlet of the first reversing valve is communicated with the first end of the variable cylinder; the outlet of the second reversing valve is communicated with the second end of the variable cylinder; the outlet of the third reversing valve is communicated with the first overflow valve; the inlet of the foot valve is communicated with the outlet of the first throttle valve, and the outlet of the foot valve is communicated with the oil supplementing port of the plunger pump. The hydraulic system can realize low vehicle speed under the condition of high engine speed, and can control the vehicle speed under the condition of constant engine speed.
Description
Technical Field
The utility model relates to a hydraulic control technical field, in particular to hydraulic system and vehicle.
Background
In the existing hydraulic system, the higher the engine speed, the larger the pump displacement and the faster the vehicle speed, and the low vehicle speed requirement under the high engine speed can not be realized. Meanwhile, the engine does not have the capacity of controlling the variable of the pump under the constant rotating speed, the speed change cannot be realized, and the working condition requirements of vehicles in different industries cannot be met.
SUMMERY OF THE UTILITY MODEL
The utility model provides a hydraulic system and vehicle, above-mentioned hydraulic system can realize the demand of low speed of a motor vehicle under the high rotational speed's of engine condition to and can realize the purpose of controlling the speed of a motor vehicle under the condition of the invariable rotational speed of engine.
In order to achieve the above purpose, the utility model provides the following technical scheme:
a hydraulic system comprises an engine, a gear pump, a variable cylinder, a plunger pump, a valve block and a foot valve; the engine is used for driving the gear pump; the gear pump is used for adjusting the output of the variable cylinder through the valve block; the variable cylinder is used for adjusting the angle of a swash plate of the plunger pump; the valve block includes: the oil inlet, the first throttle valve, the first throttling damper, the second throttling damper, the first reversing valve, the second reversing valve, the third reversing valve and the first overflow valve; wherein,
the oil inlet is communicated with the gear pump;
an inlet of the first throttling valve is communicated with the oil inlet, and an outlet of the first throttling valve is respectively communicated with a first inlet of the first reversing valve, a first inlet of the second reversing valve and an inlet of the third reversing valve;
an inlet of the first throttling damper is communicated with the oil inlet, an outlet of the first throttling damper is respectively communicated with a second inlet of the first reversing valve and a second inlet of the second reversing valve, and the outlet pressure of the first throttling damper is lower than the outlet pressure of the first throttling valve;
an inlet of the second throttling damper is communicated with the oil inlet, an outlet of the second throttling damper is communicated with an oil supplementing port of the plunger pump, and the first throttling damper is communicated with the oil inlet through the second throttling damper;
the outlet of the first reversing valve is communicated with the first end of the variable cylinder;
the outlet of the second reversing valve is communicated with the second end of the variable cylinder;
the outlet of the third reversing valve is communicated with the first overflow valve;
and an inlet of the pedal valve is communicated with an outlet of the first throttling valve, and an outlet of the pedal valve is communicated with an oil supplementing port of the plunger pump.
Above-mentioned embodiment of the utility model provides an among the hydraulic system, the gear pump is the guide's pump also simultaneously and is the oil supplementing pump, can be through the pressure differential of the oil supplementing mouth of first choke valve, first throttle damping and second throttle damping control oil inlet and plunger pump, can be through the direction of the swash plate of the state control plunger pump (the direction that the vehicle moved forward and backward) of adjusting first switching-over valve and second switching-over valve. The hydraulic system can realize an engine rotating speed control mode, in the mode, the third reversing valve can be controlled to be powered off, the second throttling damper can control the pressure difference between the oil inlet and the oil supplementing opening of the plunger pump (namely the pressure difference between the first end of the variable cylinder and the second end of the variable cylinder), when the rotating speed of the engine rises, the pressure difference between the oil inlet and the oil supplementing opening of the plunger pump rises, the higher the pressure difference is, the larger the displacement of the plunger pump is, the faster the vehicle speed is, and when the vehicle is under some special working conditions, the vehicle also has a working system besides a walking system, in order to keep the high power output of the working system, the engine is required to maintain the high rotating speed, but the vehicle speed requirement is lower, the displacement of the plunger pump can be controlled by overriding the foot valve, the pressure difference between the first end of the variable cylinder and the second end of the variable cylinder is reduced, and the requirement of the low vehicle speed of the engine under the high rotating speed can be realized. The hydraulic system can also realize a constant rotating speed mode of the engine, in the constant rotating speed mode, the third reversing valve is powered on, the engine maintains constant rotating speed, the pressure difference between the oil inlet and the oil supplementing port of the plunger pump is constant, at the moment, the pressure of the oil inlet can be consistent with that of the oil supplementing port of the plunger pump by adjusting the set current of the first overflow valve, the pressure difference is zero, the vehicle can stop, when the current of the first overflow valve is increased, the pressure of the oil inlet can be increased, the pressure difference between the oil inlet and the oil supplementing port of the plunger pump is increased, the displacement of the plunger pump can be increased, the vehicle speed is controlled to be increased, otherwise, the current of the first overflow valve is reduced, the pressure of the oil inlet can be reduced, the pressure difference between the oil inlet and the oil supplementing port of the plunger pump is reduced, the displacement of the plunger pump is reduced, the vehicle speed is controlled to be reduced, and therefore, the third reversing valve is powered on when the rotating speed of the engine is constant, The first overflow valve inputs current to control the displacement of the plunger pump, and the vehicle speed can be controlled.
Optionally, the variable cylinder and the piston disposed in the cylinder block, a first end of the variable cylinder and a second end of the variable cylinder are respectively provided with a hydraulic port communicated with two end faces of the piston, and the piston is connected with a swash plate of the plunger pump.
Optionally, an elastic member is disposed between each of the two sides of the piston and the cylinder, and the elastic force provided by the elastic members on the two sides of the piston is equal.
Optionally, the valve block further comprises a check valve, an inlet of the check valve is communicated with an outlet of the first throttling valve, and an outlet of the check valve is communicated with an outlet of the first throttling damper.
Optionally, the valve block further comprises a second overflow valve connected between the outlet of the first choke and the inlet of the first choke.
Optionally, the valve block further includes a third relief valve, and the third relief valve is communicated with the oil inlet.
Optionally, the first directional valve and the second directional valve are two-position three-way valves, and the third directional valve is a two-position two-way valve.
The utility model also provides a vehicle, including the arbitrary hydraulic system who provides among the above-mentioned technical scheme.
Drawings
Fig. 1 is a schematic structural diagram of a hydraulic system according to an embodiment of the present invention;
fig. 2 is a schematic structural diagram of a variable cylinder provided in an embodiment of the present invention.
Icon:
1-a gear pump; 2-variable cylinder; 21-cylinder body; 22-a piston; 3-a plunger pump; 31-oil supplementing port; 411 — first throttle valve; 412 — first throttle damping; 413-second throttle damping; 421-a first directional valve; 422-a second direction valve; 423-third direction valve; 431-a first overflow valve; 432-a second relief valve; 433-a third overflow valve; 44-a one-way valve; 5-foot valve.
Detailed Description
The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative work belong to the protection scope of the present invention.
Referring to fig. 1, the present invention provides a hydraulic system, which includes an engine, a gear pump 1, a variable cylinder 2, a plunger pump 3, a valve block, and a foot valve 5; the engine is used for driving the gear pump 1; the gear pump 1 is used for adjusting the output of the variable cylinder 2 through a valve block; the variable cylinder 2 is used for adjusting the angle of a swash plate of the plunger pump 3; the valve block includes: an oil inlet P, a first throttling valve 411, a first throttling damper 412, a second throttling damper 413, a first reversing valve 421, a second reversing valve 422, a third reversing valve 423 and a first overflow valve 431; wherein,
the oil inlet P is communicated with the gear pump 1;
an inlet of the first throttle valve 411 is communicated with the oil inlet P, and an outlet of the first throttle valve 411 is respectively communicated with a first inlet of the first reversing valve 421, a first inlet of the second reversing valve 422 and an inlet of the third reversing valve 423;
an inlet of the first throttling damper 412 is communicated with the oil inlet P, an outlet of the first throttling damper 412 is respectively communicated with a second inlet of the first reversing valve 421 and a second inlet of the second reversing valve 422, and the outlet pressure of the first throttling damper 412 is lower than the outlet pressure of the first throttling valve 411;
an inlet of the second throttling damper 413 is communicated with the oil inlet P, an outlet of the second throttling damper 413 is communicated with the oil supplementing port 31 of the plunger pump 3, and the first throttling damper 412 is communicated with the oil inlet P through the second throttling damper 413;
the outlet of the first reversing valve 421 is communicated with the first end of the variable cylinder 2;
the outlet of the second reversing valve 422 is communicated with the second end of the variable cylinder 2;
the outlet of the third directional valve 423 is communicated with the first relief valve 431;
an inlet of the foot valve 5 communicates with an outlet of the first throttle valve 411, and an outlet of the foot valve 5 communicates with the oil supply port 31 of the plunger pump 3.
Above-mentioned embodiment of the utility model provides an among the hydraulic system, gear pump 1 is the guide's pump also simultaneously and is the oil supplementing pump, can control the pressure differential of oil inlet and the oil supplementing mouth of plunger pump through first choke valve, first throttle damping and second throttle damping, can control the direction of the swash plate of plunger pump 3 (the direction that the vehicle moved forward and backward) through first switching-over valve 421 and second switching-over valve 422. The hydraulic system can realize an engine speed control mode, in this mode, the third reversing valve 423 can be controlled to be powered off, the second throttling damper 413 can control the pressure difference between the oil inlet P and the oil supplementing port 31 of the plunger pump 3 (the pressure difference between the port P and the port F in fig. 1, namely, the pressure difference between the first end of the variable cylinder 2 and the second end of the variable cylinder 2, and the pressure difference between the port Y and the port Z in fig. 1), when the engine speed increases, the pressure difference between the oil inlet P and the oil supplementing port 31 of the plunger pump 3 increases, the higher the pressure difference is, the larger the displacement of the plunger pump 3 is, and the faster the vehicle speed is. Under some special working conditions, the vehicle is provided with a working system besides a walking system, the engine is required to maintain high rotating speed in order to keep high power output of the working system, but the requirement on the vehicle speed is low, the displacement of the plunger pump 3 can be controlled by overriding the pedal valve 5, the pressure difference between the first end of the variable cylinder 2 and the second end of the variable cylinder 2 is reduced, and the requirement on the low vehicle speed of the engine under the high rotating speed can be realized. The hydraulic system can also realize a constant rotating speed mode of the engine, in this mode, the third reversing valve 423 is powered on, the engine maintains constant rotating speed, the pressure difference between the oil inlet P and the oil replenishing port 31 of the plunger pump 3 is constant, the vehicle speed is constant, at the moment, the pressure of the oil inlet P and the pressure of the oil replenishing port 31 of the plunger pump 3 can be consistent by adjusting the set current of the first overflow valve 431, the pressure difference is zero, the vehicle can stop, when the current of the first overflow valve 431 is increased, the pressure of the oil inlet P can be increased, the pressure difference between the oil inlet P and the oil replenishing port 31 of the plunger pump 3 is increased, the displacement of the plunger pump 3 can be increased, the vehicle speed is controlled to be increased, otherwise, the current of the first overflow valve 431 is reduced, the pressure of the oil inlet P can be reduced, the pressure difference between the oil inlet P and the oil replenishing port 31 of the plunger pump 3 can be reduced, the displacement of the plunger pump 3 can be reduced, and the vehicle speed is controlled to be reduced, therefore, when the engine speed is constant, the displacement of the plunger pump 3 is controlled by the energization of the third selector valve 423 and the input current of the first relief valve 431, and the vehicle speed can be controlled.
The embodiment of the utility model provides a hydraulic system, third switching-over valve has been increased on prior art's basis, first overflow valve and foot valve, under some special operating mode, can realize the override control to the plunger pump discharge capacity, for example, can realize the demand of low speed of a motor vehicle under the high rotational speed's of engine condition, and can realize the control to the speed of a motor vehicle size under the condition of the invariable rotational speed of engine, in addition, can also realize the invariable demand of speed of a motor vehicle under the condition of engine speed change through third switching-over valve and first overflow valve output current size, and the cost of realization is lower, compare with the hydraulic system who only adapts to pure walking operating mode among the prior art, the utility model provides a hydraulic system function richly can adapt to multiple operating mode requirement.
Specifically, in the above embodiment, the first direction valve 421, the second direction valve 422, and the third direction valve 423 may be electrically controlled direction valves. The first direction valve 421 and the second direction valve 422 may be two-position three-way direction valves, and the third direction valve 423 may be two-position two-way direction valves.
Specifically, the variable cylinder 2 includes a cylinder block 21 and a piston 22 disposed in the cylinder block 21, a first end and a second end of the variable cylinder 2 are respectively provided with a hydraulic port communicating with both end surfaces of the piston 22, and the piston 22 is directly or indirectly connected with a swash plate of the plunger pump 3. The valve body is used to adjust the position of the piston 22 of the variable cylinder 2 and thus the angle of the swash plate.
Alternatively, elastic members are provided between both sides of the piston 22 and the cylinder 21, and the elastic force provided by the elastic members on both sides of the piston 22 is equal. In particular, the elastic member may be a spring.
For example, as shown in fig. 2, the variable cylinder is a torque control variable mechanism, P '/S' is a system high pressure, YZ is a pilot control pressure, and each pressure and piston action area on the variable cylinder are balanced with the elastic force of a spring. When the engine speed increases, the pressure difference between the ports P and F (i.e., the pressure difference between the ports Y, Z) increases, and when the set pressure of the pilot variable spring a1/a2 of the variable cylinder 2 is reached, the displacement of the plunger pump 3 starts to change.
Specifically, when the direction of the swash plate of the plunger pump 3 (the direction in which the vehicle advances and retreats) is controlled by the first direction changing valve 421 and the second direction changing valve 422, in the first state, the outlet of the first throttle valve 411 is communicated with the first end of the variable cylinder 2, and the outlet of the first throttle damper 412 is communicated with the second end of the variable cylinder 2 by controlling the first direction changing valve 421 and the second direction changing valve 422, so that the pressure at the first end of the variable cylinder 2 is greater than the pressure at the second end of the variable cylinder 2, and at this time, the plunger pump 3 supplies oil in the forward direction, and the motor driven by the plunger pump 3 rotates in the forward direction, that is, the motor rotates in the direction in which the vehicle advances; in the second state, the outlet of the first throttle valve 411 is communicated with the second end of the variable cylinder 2, and the outlet of the first throttle damper 412 is communicated with the first end of the variable cylinder 2 by controlling the first direction changing valve 421 and the second direction changing valve 422, so that the pressure at the second end of the variable cylinder 2 is greater than the pressure at the first end of the variable cylinder 2, and at this time, the plunger pump 3 is supplied with oil in reverse, and the motor driven by the plunger pump 3 is rotated in reverse, that is, the motor is rotated in a direction to move the vehicle backward.
Specifically, the valve block may further include a check valve 44, an inlet of the check valve 44 being in communication with an outlet of the first throttle valve 411, and an outlet of the check valve 44 being in communication with an outlet of the first orifice damper 412. When an oil pipe at the outlet of the first reversing valve 421 is broken, the first end of the variable cylinder 2 loses oil pressure, and the second end of the variable cylinder 2 normally supplies oil, which may cause reverse oil supply of the plunger pump 3, and this is a danger that a hydraulic system may control a vehicle to suddenly travel backward from normal travel, and the one-way valve 44 is arranged to open when the oil pipe at the outlet a of the first reversing valve 421 is broken, so that a part of oil originally flowing from the first throttle damper 412 to the second reversing valve 422 is guided to the first reversing valve 421, and pressure values at the outlet of the first reversing valve 421 and the outlet of the second reversing valve 422 are equal, that is, pressures at two ends of the variable cylinder 2 are equal, at this time, the swash plate angle of the plunger pump 3 is substantially zero, and the plunger pump 3 has no variable, so that the vehicle stops, thereby ensuring driving safety.
Specifically, the valve block may further include a second overflow valve 432, the second overflow valve 432 being connected between the outlet of the first orifice 411 and the inlet of the first orifice damper 412. When the pressure difference between the outlet of the first throttle valve 411 and the inlet of the first throttle damper 412 is higher than a preset value, the second overflow valve 432 is opened, and part of oil flows to the first throttle damper 412 from the first throttle valve 411, so that the pressure difference between the two sides of the variable cylinder 2 is reduced, and the displacement of the plunger pump 3 is further ensured not to be too large.
Specifically, the valve block further comprises a third overflow valve 433, and the third overflow valve 433 is communicated with the oil inlet P and can stabilize system pressure.
The utility model also provides a vehicle, including the arbitrary hydraulic system who provides among the above-mentioned technical scheme.
It will be apparent to those skilled in the art that various changes and modifications may be made to the embodiments of the present invention without departing from the spirit and scope of the invention. Thus, if such modifications and variations of the present invention fall within the scope of the claims and their equivalents, the present invention is also intended to include such modifications and variations.
Claims (8)
1. A hydraulic system is characterized by comprising an engine, a gear pump, a variable cylinder, a plunger pump, a valve block and a pedal valve; the engine is used for driving the gear pump; the gear pump is used for adjusting the output of the variable cylinder through the valve block; the variable cylinder is used for adjusting the angle of a swash plate of the plunger pump; the valve block includes: the oil inlet, the first throttle valve, the first throttling damper, the second throttling damper, the first reversing valve, the second reversing valve, the third reversing valve and the first overflow valve; wherein,
the oil inlet is communicated with the gear pump;
an inlet of the first throttling valve is communicated with the oil inlet, and an outlet of the first throttling valve is respectively communicated with a first inlet of the first reversing valve, a first inlet of the second reversing valve and an inlet of the third reversing valve;
an inlet of the first throttling damper is communicated with the oil inlet, an outlet of the first throttling damper is respectively communicated with a second inlet of the first reversing valve and a second inlet of the second reversing valve, and the outlet pressure of the first throttling damper is lower than the outlet pressure of the first throttling valve;
an inlet of the second throttling damper is communicated with the oil inlet, an outlet of the second throttling damper is communicated with an oil supplementing port of the plunger pump, and the first throttling damper is communicated with the oil inlet through the second throttling damper;
the outlet of the first reversing valve is communicated with the first end of the variable cylinder;
the outlet of the second reversing valve is communicated with the second end of the variable cylinder;
the outlet of the third reversing valve is communicated with the first overflow valve;
and the inlet of the foot valve is communicated with the outlet of the first throttling valve, and the outlet of the foot valve is communicated with the oil supplementing port of the plunger pump.
2. The hydraulic system of claim 1, wherein the variable cylinder comprises a cylinder body and a piston disposed in the cylinder body, a first end of the variable cylinder and a second end of the variable cylinder are respectively provided with a hydraulic port communicating with both end surfaces of the piston, and the piston is connected with a swash plate of the plunger pump.
3. The hydraulic system of claim 2, wherein elastic members are disposed between both sides of the piston and the cylinder, and the elastic members on both sides of the piston provide equal elastic force.
4. The hydraulic system of claim 1, wherein the valve block further comprises a check valve having an inlet in communication with an outlet of the first throttle valve and an outlet in communication with an outlet of the first throttle damper.
5. The hydraulic system of claim 1, wherein the valve block further comprises a second spill valve connected between the outlet of the first choke and the inlet of the first choke.
6. The hydraulic system of claim 1, wherein the valve block further includes a third spill valve in communication with the oil inlet.
7. The hydraulic system of claim 1, wherein the first and second directional valves are two-position, three-way valves and the third directional valve is a two-position, two-way valve.
8. A vehicle, characterized in that it comprises a hydraulic system according to any one of claims 1-7.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202122862635.0U CN217107217U (en) | 2021-11-22 | 2021-11-22 | Hydraulic system and vehicle |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202122862635.0U CN217107217U (en) | 2021-11-22 | 2021-11-22 | Hydraulic system and vehicle |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN217107217U true CN217107217U (en) | 2022-08-02 |
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ID=82588806
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202122862635.0U Active CN217107217U (en) | 2021-11-22 | 2021-11-22 | Hydraulic system and vehicle |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN217107217U (en) |
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2021
- 2021-11-22 CN CN202122862635.0U patent/CN217107217U/en active Active
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