CN220337171U - Hydraulic control system - Google Patents
Hydraulic control system Download PDFInfo
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- CN220337171U CN220337171U CN202322030305.4U CN202322030305U CN220337171U CN 220337171 U CN220337171 U CN 220337171U CN 202322030305 U CN202322030305 U CN 202322030305U CN 220337171 U CN220337171 U CN 220337171U
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- 238000006073 displacement reaction Methods 0.000 claims description 12
- 238000013016 damping Methods 0.000 claims description 8
- 238000004891 communication Methods 0.000 claims description 6
- 230000001105 regulatory effect Effects 0.000 claims description 6
- 230000000694 effects Effects 0.000 abstract description 10
- 230000010485 coping Effects 0.000 abstract 1
- 239000003921 oil Substances 0.000 description 55
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 6
- 229910052782 aluminium Inorganic materials 0.000 description 6
- 230000007246 mechanism Effects 0.000 description 6
- 230000009471 action Effects 0.000 description 3
- 238000010586 diagram Methods 0.000 description 3
- 239000007788 liquid Substances 0.000 description 3
- 230000009286 beneficial effect Effects 0.000 description 2
- 230000001276 controlling effect Effects 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 230000008569 process Effects 0.000 description 2
- 230000006641 stabilisation Effects 0.000 description 2
- 238000011105 stabilization Methods 0.000 description 2
- 230000033228 biological regulation Effects 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 230000003749 cleanliness Effects 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 238000001125 extrusion Methods 0.000 description 1
- 239000010720 hydraulic oil Substances 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 238000004519 manufacturing process Methods 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
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Abstract
The present utility model provides a hydraulic control system, comprising: the variable pump assembly, the main control valve group, the straightening main cylinder and the flow control valve group; an oil inlet of the main control valve group is communicated with an oil outlet of the variable pump assembly; the rodless cavity and the rod cavity of the straightening main cylinder are respectively communicated with two working oil ports of the main control valve group; and an inlet oil way of the flow control valve bank is communicated with the variable pump assembly, and the flow control valve bank comprises a second electromagnetic reversing valve, a high-pressure proportional overflow valve and a low-pressure overflow valve. Through the export oil circuit intercommunication flow control valves at the variable pump subassembly, utilize the second electromagnetic reversing valve to switch high pressure ratio overflow valve, low pressure overflow valve to the oil pressure when coping with variable pump subassembly standby condition and operating mode difference, thereby utilize the constant pressure overflow effect of overflow valve, play steady voltage and safety protection's effect to whole hydraulic control system, thereby play the effect that improves system stability.
Description
Technical Field
The utility model relates to the technical field of hydraulic oil ways, in particular to a hydraulic control system.
Background
In the process of aluminum profile production, the aluminum profile needs to be straightened through a straightening machine after extrusion forming, and the straightening machine comprises a fixed head device and a movable head device capable of moving on a movable track, and is in the straightening process. After the moving head device is fixed on the moving track, the fixed head device and the moving head device can stretch the aluminum profile respectively.
Because the lengths of the aluminum profiles are different, the straightening main cylinders of the fixing head device have different straightening forces when the straightening main cylinders perform straightening work, and when the straightening main cylinders have overlarge straightening forces, the aluminum profiles are easy to pinch off; when the straightening force of the straightening main cylinder is too small, the aluminum profile is easy to slide away from the fixing head device due to the fact that the clamping is large. Therefore, the hydraulic control system corresponding to the fixed head device can adopt a load-sensitive variable pump to control the straightening main cylinder, so that the straightening efficiency of the straightening main cylinder is improved.
Publication number CN207033865U discloses a load sensitive variable system comprising: the pump body and the variable adjusting mechanism; one end of the main oil way is connected with the pump body, and a main valve is also arranged on the main oil way and used for controlling the connection or disconnection of the main oil way; one end of the load sensitive feedback oil circuit is connected with the main oil circuit, and the other end of the load sensitive feedback oil circuit is connected with the variable adjusting mechanism; the load sensitive control component is arranged on the load sensitive feedback oil path and is used for controlling the connection or disconnection of the load sensitive feedback oil path and the variable adjusting mechanism, and the variable adjusting mechanism adjusts the opening angle of the pump body according to the oil pressure in the load sensitive feedback oil path; when the main valve is in an open state, the load sensitive feedback oil circuit is connected with the variable adjusting mechanism, and when the main valve is in a closed state, the load sensitive feedback oil circuit is disconnected with the variable adjusting mechanism. The variable system solves the problem that the variable system in the prior art is easy to cause energy loss.
However, when the variable pump in the hydraulic control system is in a pressure-raising or standby working condition, the outlet pressure of the variable pump is higher, so that the hydraulic control system is impacted, and the problems of hydraulic energy efficiency loss and low system stability are caused.
Disclosure of Invention
Based on the above, in order to solve the problems of higher outlet pressure and low system stability of the variable pump in the hydraulic control system when the variable pump is in a lifting or standby working condition, the utility model provides a hydraulic control system, which has the following specific technical scheme:
a hydraulic control system, comprising:
a variable displacement pump assembly;
the oil inlet of the main control valve group is communicated with the oil outlet of the variable pump assembly;
the rodless cavity and the rod cavity of the straightening main cylinder are respectively communicated with two working oil ports of the main control valve group;
the flow control valve bank comprises a second electromagnetic reversing valve, a high-pressure proportional overflow valve and a low-pressure overflow valve, wherein a P port of the second electromagnetic reversing valve is communicated with the variable pump assembly, an A port and a B port of the second electromagnetic reversing valve are respectively communicated with the high-pressure proportional overflow valve and the low-pressure overflow valve, and a T port of the second electromagnetic reversing valve is communicated with an oil tank.
According to the hydraulic control system, the outlet oil way of the variable pump assembly is communicated with the flow control valve group, the second electromagnetic reversing valve is used for switching the high-pressure proportional overflow valve and the low-pressure overflow valve, so that oil pressures different in standby working condition and operation working condition of the variable pump assembly are handled, the constant-pressure overflow effect of the overflow valve is utilized, the effects of pressure stabilization and safety protection are achieved on the whole hydraulic control system, and the effect of improving the system stability is achieved.
Further, the variable pump assembly comprises a pump body and a variable adjustment group, and an oil outlet of the pump body is communicated with the variable adjustment group;
the variable adjustment group comprises at least three load sensitive valves which are communicated in parallel, and an oil outlet of the variable adjustment group is communicated with a P port of the second electromagnetic directional valve.
Further, the flow control valve group further comprises a damping device, and the damping device is arranged between the variable adjustment group and the P port of the second electromagnetic directional valve.
Further, the main control valve group comprises a first electrohydraulic reversing valve and a first hydraulic reversing valve, the outlet end of the variable pump assembly is communicated with the P port of the first electrohydraulic reversing valve, the A port and the B port of the first electrohydraulic reversing valve are respectively communicated with the control cavity of the first hydraulic reversing valve, and the A port and the B port of the first hydraulic reversing valve are respectively communicated with the rodless cavity and the rod-containing cavity of the straightening master cylinder; the T-shaped opening of the first hydraulic reversing valve and the T-shaped opening of the first electro-hydraulic reversing valve are communicated with the oil tank through the same oil way.
Further, a pressure sensor and a pressure measuring joint are arranged between the port A of the first hydraulic reversing valve and the rodless cavity of the straightening main cylinder.
Further, a first overflow valve is arranged at the P port of the first hydraulic reversing valve.
Further, a second overflow valve is arranged at the P port of the first electro-hydraulic reversing valve.
Further, the hydraulic control system also comprises a regulating valve group arranged at the T-port of the first hydraulic reversing valve; the regulating valve group comprises a cooler and a return oil filter, and the return oil filter comprises a pressure relay and a filter with a one-way valve.
Further, a first pressure gauge is arranged between the variable pump assembly and the P port of the first hydraulic reversing valve, and the first pressure gauge is used for detecting oil pressure of a corresponding communication oil way.
Further, a pressure control valve is arranged between the variable pump assembly and the P port of the first hydraulic reversing valve.
Drawings
The utility model will be further understood from the following description taken in conjunction with the accompanying drawings. The components in the figures are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the embodiments. Like reference numerals designate corresponding parts throughout the different views.
FIG. 1 is a structural frame diagram of a hydraulic control system according to an embodiment of the present utility model;
FIG. 2 is a structural frame diagram of a variable displacement pump assembly and flow control valve block according to one embodiment of the present utility model;
fig. 3 is a structural frame diagram of a master control valve block and a straightening master cylinder according to an embodiment of the present utility model.
Reference numerals illustrate:
1. a variable displacement pump assembly; 2. a main control valve group; 4. straightening a main cylinder; 5. a flow control valve block;
11. a pump body; 12. a variable adjustment group; 121. a load-sensitive valve;
21. a first electro-hydraulic reversing valve; 22. a first hydraulic reversing valve; 23. a pressure sensor; 24. a pressure measuring joint; 25. a first overflow valve; 26. a second overflow valve; 27. a regulating valve group; 28. a first pressure gauge; 29. a pressure control valve;
271. a cooler; 272. a return oil filter;
51. a second electromagnetic directional valve; 52. a high pressure proportional relief valve; 53. a low pressure overflow valve; 54. damping device.
Detailed Description
The present utility model will be described in further detail with reference to the following examples thereof in order to make the objects, technical solutions and advantages of the present utility model more apparent. It should be understood that the detailed description and specific examples are intended for purposes of illustration only and are not intended to limit the scope of the utility model.
It will be understood that when an element is referred to as being "fixed to" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "left," "right," and the like are used herein for illustrative purposes only and are not meant to be the only embodiment.
Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this utility model belongs. The terminology used herein in the description of the utility model is for the purpose of describing particular embodiments only and is not intended to be limiting of the utility model. The term "and/or" as used herein includes any and all combinations of one or more of the associated listed items.
The terms "first" and "second" in this specification do not denote a particular quantity or order, but rather are used to distinguish one element from another.
As shown in fig. 1 and 2, a hydraulic control system according to an embodiment of the present utility model includes:
a variable displacement pump assembly 1;
the oil inlet of the main control valve group 2 is communicated with the oil outlet of the variable pump assembly 1;
the straightening main cylinder 4, a rodless cavity and a rod cavity of the straightening main cylinder 4 are respectively communicated with two working oil ports of the main control valve group 2;
the flow control valve group 5, the inlet oil way of the flow control valve group 5 is communicated with the variable pump assembly 1, the flow control valve group 5 comprises a second electromagnetic directional valve 51, a high-pressure proportional overflow valve 52 and a low-pressure overflow valve 53, the P port of the second electromagnetic directional valve 51 is communicated with the flow control valve group 5, the A port and the B port of the second electromagnetic directional valve 51 are respectively communicated with the high-pressure proportional overflow valve 52 and the low-pressure overflow valve 53, and the T port of the second electromagnetic directional valve 51 is communicated with the oil tank.
According to the hydraulic control system, the outlet oil way of the variable pump assembly 1 is communicated with the flow control valve group 5, the second electromagnetic directional valve 51 is utilized to switch the high-pressure proportional relief valve 52 and the low-pressure relief valve 53, so that oil pressures of the variable pump assembly 1 in different standby working conditions and operation working conditions are handled, the constant-pressure relief effect of the relief valve is utilized, the effects of pressure stabilization and safety protection are achieved on the whole hydraulic control system, and the effect of improving the system stability is achieved.
As shown in fig. 2, in one embodiment, the variable pump assembly 1 includes a pump body 11 and a variable adjustment group 12, and an oil outlet of the pump body 11 communicates with the variable adjustment group 12; the variable adjustment group 12 comprises at least three load sensitive valves 121 which are communicated in parallel, and the oil outlet of the variable adjustment group 12 is communicated with the P port of the second electromagnetic directional valve 51. Thus, when the main control valve group 2 is just switched to the working position, the pressure output by the pump body 11 can not push the load yet, the flow rate passing through the main control valve group 2 is 0, the pressures at the two ends of the load sensitive valve 121 are the same, the right position works under the action of spring force, and the pump is in the working condition of maximum displacement; when the main control valve group 2 is switched to a working position, the pressure of oil output by the pump body 11 pushes the load, and high-pressure oil output by the pump body 11 passes through the opening of the main control valve group 2 and enters the straightening main cylinder 4 to push the load to work.
Specifically, the flow output by the pump passes through the port of the main control valve group 2 except leakage, when the main control valve group 2 is opened, and when the valve port has a certain opening degree, the valve core stress of the load sensitive valve 121 has three conditions: 1) When fp=fpls+f bomb, the median function of the load-sensitive valve 121 works, the oil port of the variable cylinder is closed, the displacement of the pump body 11 is at a constant value, and the straightening master cylinder 4 moves at a constant speed; 2) When FP < fpls+f bullet, the spool moves left (the spring stiffness and spool displacement are smaller, the change of the spring force when the spool moves is not considered), the right position works, the variable cylinder is connected with the oil tank, the displacement of the pump body 11 is increased under the action of the spring force, so that the output flow of the pump body 11 is increased, the opening of the valve port of the main control valve group 2 is unchanged, the pressure drop of the valve port is increased, PLS is determined by the load, and Δp is increased, so that the output pressure P of the pump body 11 is increased until fp=fpls+f bullet; 3) When FP > fpls+f bullets, the spool moves right, left-hand operation, pressure oil enters the variable cylinder, resulting in a decrease in displacement of pump body 11, i.e. a decrease in flow through main control valve block 2, a decrease in pressure drop Δp, resulting in a decrease in P, until fp=fpls+f bullets. Therefore, the load-sensitive valve 121 maintains a constant pressure difference by its own regulating function regardless of the variation in the valve port opening.
In one embodiment, the flow control valve block 5 further includes a damping device 54, and the damping device 54 is disposed between the variable adjustment block 12 and the P port of the second electromagnetic directional valve 51. Thus, by arranging the damping device 54, when the variable pump assembly 1 is started and standby, the damping device 54 is utilized to filter out the severe fluctuation of the load feedback pressure, thereby being beneficial to the stable control of the variable adjustment group 12, avoiding the unstable condition of the output pressure, reducing the energy efficiency loss and the hydraulic system impact and improving the stability of the hydraulic system
As shown in fig. 1 and 3, in one embodiment, the main control valve group 2 includes a first electro-hydraulic directional valve 21 and a first hydraulic directional valve 22, an outlet end of the variable pump assembly 1 is communicated with a P port of the first electro-hydraulic directional valve 21, a port a and a port B port of the first electro-hydraulic directional valve 21 are respectively communicated with a control cavity of the first hydraulic directional valve 22, and a port a and a port B port of the first hydraulic directional valve 22 are respectively communicated with a rodless cavity and a rod cavity of the straightening master cylinder 4; the T port of the first hydraulic reversing valve 22 and the T port of the first electro-hydraulic reversing valve 21 are communicated with the oil tank through the same oil way. In this way, the first electrohydraulic reversing valve 21 is utilized to carry out reversing control on the first hydraulic reversing valve 22, so that the advantages of quick response of electromagnetic control and large driving force of hydraulic control are combined, and the control efficiency is improved.
In one embodiment, a pressure sensor 23 and a pressure measuring joint 24 are arranged between the port A of the first hydraulic directional valve 22 and the rodless cavity of the straightening master cylinder 4. In this way, the pressure sensor 23 and the pressure measuring joint 24 are arranged to facilitate the detection of the hydraulic pressure of the rodless cavity of the straightening master cylinder 4, which is beneficial to improving the safety of the hydraulic control system.
In one embodiment, the port P of the first hydraulic directional valve 22 is provided with a first relief valve 25. In this way, the oil pressure of the P port of the first hydraulic directional valve 22 can be adjusted by using the first relief valve 25 as a pressure regulating valve.
In one embodiment, port P of the first electro-hydraulic directional valve 21 is provided with a second relief valve 26. In this way, the first overflow valve 25 and the second overflow valve 26 are used for coacting to form a sequence valve, so that the sequential work of the first electro-hydraulic reversing valve 21 and the first hydraulic reversing valve 22 is realized, and the control effect of the hydraulic control system is ensured.
In one embodiment, the hydraulic control system further comprises a regulator valve block 27 provided at the T-port of the first hydraulic reversing valve 22; the regulator valve block 27 includes a cooler 271 and a return oil filter 272, the return oil filter 272 including a pressure relay and a filter with a check valve. Thus, the cooler 271 is used for cooling the oil liquid of the hydraulic control system, so that the temperature of the system is ensured; meanwhile, impurities of the oil liquid are filtered through the filter with the one-way valve, so that the cleanliness of the oil liquid is guaranteed.
In one embodiment, a first pressure gauge 28 is arranged between the variable pump assembly 1 and the P port of the first hydraulic reversing valve 22, and the first pressure gauge 28 is used for detecting the oil pressure of the corresponding communication oil path. Thus, the first pressure gauge 28 is used for detecting the oil pressure of the corresponding communication oil path, so as to conveniently observe whether the corresponding communication oil path is leaked with oil.
In one embodiment, a pressure control valve 29 is provided between the variable displacement pump assembly 1 and port P of the first hydraulic reversing valve 22. In this way, the reversing operation of the first hydraulic reversing valve 22 is reliably stabilized by the pressure regulation and the constant pressure action of the pressure control valve 29.
The technical features of the above embodiments may be arbitrarily combined, and all possible combinations of the technical features in the above embodiments are not described for brevity of description, however, as long as there is no contradiction between the combinations of the technical features, they should be considered as the scope of the description.
The foregoing examples illustrate only a few embodiments of the utility model, which are described in detail and are not to be construed as limiting the scope of the utility model. It should be noted that it will be apparent to those skilled in the art that several variations and modifications can be made without departing from the spirit of the utility model, which are all within the scope of the utility model. Accordingly, the scope of protection of the present utility model is to be determined by the appended claims.
Claims (10)
1. A hydraulic control system, comprising:
a variable displacement pump assembly;
the oil inlet of the main control valve group is communicated with the oil outlet of the variable pump assembly;
the rodless cavity and the rod cavity of the straightening main cylinder are respectively communicated with two working oil ports of the main control valve group;
the flow control valve bank comprises a second electromagnetic reversing valve, a high-pressure proportional overflow valve and a low-pressure overflow valve, wherein a P port of the second electromagnetic reversing valve is communicated with the variable pump assembly, an A port and a B port of the second electromagnetic reversing valve are respectively communicated with the high-pressure proportional overflow valve and the low-pressure overflow valve, and a T port of the second electromagnetic reversing valve is communicated with an oil tank.
2. The hydraulic control system of claim 1, wherein the variable pump assembly comprises a pump body and a variable adjustment group, the pump body oil outlet being in communication with the variable adjustment group;
the variable adjustment group comprises at least three load sensitive valves which are communicated in parallel, and an oil outlet of the variable adjustment group is communicated with a P port of the second electromagnetic directional valve.
3. The hydraulic control system of claim 2, wherein the flow control valve block further comprises a damping device disposed between the variable adjustment block and the P port of the second electromagnetic directional valve.
4. The hydraulic control system of claim 1, wherein the main control valve block comprises a first electro-hydraulic reversing valve and a first hydraulic reversing valve, the outlet end of the variable pump assembly is communicated with the port P of the first electro-hydraulic reversing valve, the port a and the port B of the first electro-hydraulic reversing valve are respectively communicated with the control cavity of the first hydraulic reversing valve, and the port a and the port B of the first hydraulic reversing valve are respectively communicated with the rodless cavity and the rod-containing cavity of the straightening master cylinder;
the T-shaped opening of the first hydraulic reversing valve and the T-shaped opening of the first electro-hydraulic reversing valve are communicated with the oil tank through the same oil way.
5. The hydraulic control system of claim 4, wherein a pressure sensor and a pressure tap are provided between port a of the first hydraulic reversing valve and the rodless chamber of the straightening master cylinder.
6. The hydraulic control system of claim 4, wherein the first hydraulic reversing valve has a first relief valve at port P.
7. The hydraulic control system of claim 4, wherein the P port of the first electro-hydraulic directional valve is provided with a second relief valve.
8. The hydraulic control system of claim 4, further comprising a regulator valve block disposed at a T port of the first hydraulic reversing valve;
the regulating valve group comprises a cooler and a return oil filter, and the return oil filter comprises a pressure relay and a filter with a one-way valve.
9. The hydraulic control system according to claim 4, wherein a first pressure gauge is provided between the variable pump assembly and the P port of the first hydraulic directional valve, and the first pressure gauge is configured to detect the oil pressure of the corresponding communication oil path.
10. The hydraulic control system of claim 9, wherein a pressure control valve is disposed between the variable displacement pump assembly and the P port of the first hydraulic reversing valve.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202322030305.4U CN220337171U (en) | 2023-07-28 | 2023-07-28 | Hydraulic control system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202322030305.4U CN220337171U (en) | 2023-07-28 | 2023-07-28 | Hydraulic control system |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN220337171U true CN220337171U (en) | 2024-01-12 |
Family
ID=89450473
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202322030305.4U Active CN220337171U (en) | 2023-07-28 | 2023-07-28 | Hydraulic control system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN220337171U (en) |
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2023
- 2023-07-28 CN CN202322030305.4U patent/CN220337171U/en active Active
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