CN220248509U - High-order forklift and hydraulic control system thereof - Google Patents
High-order forklift and hydraulic control system thereof Download PDFInfo
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- CN220248509U CN220248509U CN202322222620.7U CN202322222620U CN220248509U CN 220248509 U CN220248509 U CN 220248509U CN 202322222620 U CN202322222620 U CN 202322222620U CN 220248509 U CN220248509 U CN 220248509U
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- 239000003921 oil Substances 0.000 claims abstract description 53
- 239000007788 liquid Substances 0.000 claims abstract description 33
- 238000001514 detection method Methods 0.000 claims abstract description 28
- 239000010720 hydraulic oil Substances 0.000 claims abstract description 12
- 230000009471 action Effects 0.000 claims description 12
- 230000007246 mechanism Effects 0.000 claims description 4
- 230000002159 abnormal effect Effects 0.000 claims description 3
- 238000000034 method Methods 0.000 claims 1
- 238000010586 diagram Methods 0.000 description 2
- 238000009434 installation Methods 0.000 description 2
- 230000007935 neutral effect Effects 0.000 description 2
- 230000008859 change Effects 0.000 description 1
- 238000006073 displacement reaction Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000012530 fluid Substances 0.000 description 1
- 230000017525 heat dissipation Effects 0.000 description 1
- 230000002706 hydrostatic effect Effects 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
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Abstract
The utility model discloses a high-order forklift truck and a hydraulic control system thereof, wherein the system comprises a load sensitive pump, a hydraulic oil tank, a steering gear, a priority valve, an LS type liquid filling valve, a brake valve, a control valve, a brake energy accumulator and a pressure detection unit; the CF port of the priority valve is simultaneously connected with the P port of the steering gear and the P port of the LS type liquid filling valve; the LS port of the LS type liquid filling valve is connected with the feedback oil port of the load sensitive pump through the shuttle valve, the LS port of the priority valve is connected with the feedback oil path between the LS type liquid filling valve and the shuttle valve, and the LS port of the steering gear is connected with the feedback oil path between the LS type liquid filling valve and the shuttle valve through the control valve. According to the utility model, the control valve is controlled to power off according to the pressure of the brake energy accumulator, so that the load feedback pressure can be unloaded during standby, and the purposes of not holding the pressure during standby and normally charging the brake energy accumulator are realized.
Description
Technical Field
The utility model belongs to the technical field of engineering machinery, and particularly relates to a high-position forklift truck and a liquid filling and steering priority hydraulic control system with LS unloading control.
Background
The high-position forklift truck hydraulic system generally comprises a traveling system, an upper truck multi-way valve system, a steering system and a traveling brake system, wherein the traveling system generally adopts an independent system of a hydrostatic drive or hydraulic torque converter, the steering system generally adopts an LS-type steering gear to control the steering action of an axle, and the arm support action and the landing leg action are controlled through the upper truck multi-way valve.
The walking braking is related to the safety of equipment and personnel, and when the equipment walks, a hydraulic system may need to simultaneously execute steering, walking braking and boarding multiplex valve actions. At present, a liquid filling valve, an energy accumulator or a pressurizing brake valve is generally adopted for running braking, and running braking control is implemented; the braking mode of the charging valve and the accumulator is two modes of a non-LS charging valve and an LS charging valve.
For the non-LS type liquid filling valve system, a single gear pump or a hydraulic pump shared with the engine heat dissipation system is used for filling liquid into the energy accumulator, the liquid filling is prioritized to ensure the normal operation of the walking braking system, and the other hydraulic load sensitive pump supplies oil to the steering and boarding multi-way valve action and distributes flow through the priority valve, as shown in figure 1. For rotary forklift trucks, this solution is not practical when the number of central swivel joint channels is limited, and may require additional gear pumps, which increases overall costs.
For the LS type liquid filling valve system, one hydraulic load sensitive pump simultaneously supplies oil to the steering gear, the LS type liquid filling valve and the on-vehicle multi-way valve, and flow distribution is carried out through the priority valve, namely, a CF port of the priority valve supplies oil to the steering gear and the LS type liquid filling valve preferentially, an EF port supplies oil to the on-vehicle multi-way valve, and LS oil pressures of the three systems are compared through the shuttle valve network and then fed back to the load sensitive pump for flow control. The problem that one pump supplies oil to three systems simultaneously and the quantity of central swivel joints is limited is solved, but because LS pressure of an LS type liquid filling valve needs to be fed back to a priority valve through a shuttle valve network, and LS continuous oil drainage is carried out through a middle position of a dynamic LS type steering system in a standby state, LS oil can be suppressed when flowing reversely through the shuttle valve network, an engine is suppressed to be flameout, or the liquid filling system cannot build pressure, and the fault risk of the system is increased.
The boost type brake valve is generally used for realizing walking braking by supplying oil through a low-pressure oil way and boosting through the brake valve, the driving braking feeling of the boost type brake valve is poor, and the boost type brake valve has larger volume due to a boost cylinder, self-carried oil pocket and the like, has higher requirement on installation space and is limited in installation.
Disclosure of Invention
The utility model aims to provide a high-position forklift truck and a hydraulic control system thereof, which are used for solving the problem that an LS (liquid-filled valve) system is blocked to cause flameout of an engine when LS oil flows reversely through a shuttle valve network, or the liquid-filled valve system cannot build pressure, so that the fault risk of the system is increased.
The utility model solves the technical problems by the following technical scheme: a hydraulic control system comprises a load sensitive pump, a hydraulic oil tank, a steering gear, a priority valve, an LS type liquid filling valve, a brake energy accumulator and a pressure detection unit; the load-sensitive pump is driven by the driving mechanism, an oil inlet of the load-sensitive pump is connected with the hydraulic oil tank, an oil outlet of the load-sensitive pump is connected with a P port of the priority valve, a CF port of the priority valve is connected with a P port of the steering gear, and an A port of the LS type liquid filling valve is simultaneously connected with an oil inlet end of the brake energy accumulator and an oil inlet end of the brake valve;
the system also comprises a control valve and a one-way valve, wherein the CF port of the priority valve is also connected with the P port of the LS type liquid filling valve; the LS port of the LS type liquid filling valve is connected with the feedback oil port of the load sensitive pump through a one-way valve and a shuttle valve in sequence, the LS port of the priority valve is connected with the feedback oil path between the one-way valve and the shuttle valve, and the LS port of the steering gear is connected with the feedback oil path between the one-way valve and the shuttle valve through a control valve; the pressure detection unit is arranged at the SW port of the LS type charging valve and is used for detecting the pressure of the brake accumulator, and the action of the control valve is controlled by the controller according to the detection value of the pressure detection unit.
Further, the control valve is one of an electromagnetic directional valve, a switching valve, a proportional valve and a servo valve.
Further, the pressure detection unit is a pressure sensor or a pressure switch.
Further, the LS-type charging valve is a single-loop charging valve or a double-loop charging valve, and when the LS-type charging valve is a single-loop charging valve, the brake valve is a single brake valve; when the LS-type charging valve is a double-loop charging valve, the brake valve is a double brake valve.
Further, an oil outlet of the load-sensitive pump is also connected with the hydraulic oil tank through an overflow valve.
Further, the steering gear, the LS type charging valve and the brake valve are all provided with T ports, and the T ports of the steering gear, the LS type charging valve and the brake valve are all connected with the hydraulic oil tank.
Further, the system further comprises an alarm connected with the controller, and when the detection value of the pressure detection unit is abnormal, the alarm gives an alarm or limits the action while giving the alarm.
Based on the same conception, the utility model also provides a high-position forklift truck, which comprises the hydraulic control system.
Advantageous effects
Compared with the prior art, the utility model has the advantages that:
according to the utility model, an LS type liquid filling valve and a load sensitive pump are adopted to supply oil to the steering gear, the brake valve and the on-board multi-way valve simultaneously, a liquid filling loop of the brake accumulator is connected with the steering gear in parallel, the load feedback pressure of the LS type liquid filling valve is fed back to the priority valve, so that the priority control of steering flow is realized, and redundant flow supplies oil to the on-board multi-way valve through an EF port of the priority valve; the load feedback pressure of the LS type liquid filling valve, the steering gear and the on-board multi-way valve is fed back to the load sensitive pump through the shuttle valve, so that the pressure and flow distribution control of steering, on-board multi-way valve and running braking is realized; a control valve is arranged on a feedback oil path of the steering gear, and the working state and the feedback unloading state of the middle position of the steering gear can be selected in real time by controlling the power-on and power-off of the control valve in combination with the detection value of the pressure detection unit.
According to the utility model, the power-on and power-off of the electromagnetic reversing valve is controlled through the pressure of the brake accumulator detected by the pressure detection unit, so that whether the charging feedback pressure and the load feedback pressure of the steering gear are at the neutral position or not is controlled, the load feedback pressure can be unloaded during standby, and the load feedback pressure can not overflow at high pressure all the time, so that the brake accumulator can not be pressurized during standby and can be charged normally, the pressure value of the brake accumulator is in a normal range, and the brake accumulator is ensured to always keep the brake reserve pressure.
Drawings
In order to more clearly illustrate the technical solutions of the present utility model, the drawings that are needed in the description of the embodiments will be briefly described below, it being obvious that the drawing in the description below is only one embodiment of the present utility model, and that other drawings can be obtained according to these drawings without inventive effort for a person skilled in the art.
FIG. 1 is a hydraulic schematic diagram of a hydraulic control system in the background of the utility model;
FIG. 2 is a hydraulic schematic diagram of a hydraulic control system in an embodiment of the present utility model, wherein a solid line represents a main oil path and a broken line represents a load feedback oil path;
FIG. 3 is a fluid charging path in an embodiment of the utility model;
fig. 4 is a feedback oil path in an embodiment of the utility model.
The hydraulic system comprises a 1-hydraulic oil tank, a 2-load sensitive pump, a 3-steering gear, a 4-shuttle valve, a 5-priority valve, a 6-charging valve, a 7-braking valve, an 8-braking energy accumulator, a 9-overflow valve, a 10-constant delivery pump, an 11-pressure detection unit, a 12-one-way valve, a 13-electromagnetic reversing valve and a 14-LS charging valve.
Detailed Description
The following description of the embodiments of the present utility model will be made more apparent and fully by reference to the accompanying drawings, in which it is shown, however, only some, but not all embodiments of the utility model. All other embodiments, which can be made by those skilled in the art based on the embodiments of the utility model without making any inventive effort, are intended to be within the scope of the utility model.
As shown in fig. 2, the hydraulic control system applied to the high-order forklift truck provided in this embodiment includes a load-sensitive pump 2, a hydraulic tank 1, a steering gear 3, a priority valve 5, an LS-type charging valve 14, a control valve, a check valve 12, a brake valve 7, a brake accumulator 8, and a pressure detection unit 13; the load-sensitive pump 2 is driven by a driving mechanism M (the driving mechanism of the embodiment is a prime motor), an oil inlet of the load-sensitive pump 2 is connected with a hydraulic oil tank 1, an oil outlet of the load-sensitive pump 2 is connected with a P port (namely an oil inlet) of a priority valve 5, a CF port (namely a priority flow port) of the priority valve 5 is simultaneously connected with a P port of a steering gear 3 and a P port of an LS type filling valve 14, an A port (namely a filling oil outlet) of the LS type filling valve 14 is simultaneously connected with an oil inlet end of a brake energy accumulator 8 and a brake valve 7, and an EF port (namely a residual flow port) of the priority valve 5 is connected with a get-on multi-way valve; the LS port of the LS type charging valve 14 is connected with the feedback oil port of the load sensitive pump 2 through the one-way valve 12 and the shuttle valve 4 in sequence, the LS port of the priority valve 5 (namely the load feedback oil port) is connected with the feedback oil path between the one-way valve 12 and the shuttle valve 4, and the LS port of the steering gear 3 is connected with the feedback oil path between the one-way valve 12 and the shuttle valve 4 through the control valve; the pressure detection means 13 is provided at the SW port (i.e., the pressure detection port) of the LS-type charging valve 14 and detects the pressure of the brake accumulator 8, and the operation of the control valve is controlled by the controller based on the detection value of the pressure detection means 13. Because of the presence of check valve 12, load feedback pressure is not relieved from LS-type charge valve 14.
According to the hydraulic control system, LS charging valves, load sensitive pumps 2 and priority valves 5 are adopted to supply oil to the steering gear 3, the brake valve 7 and the on-vehicle multi-way valves, flow distribution is carried out through the priority valves 5, steering flow priority is ensured, and a charging path is shown in figure 3. The charging pipeline is connected with the steering gear 3 in parallel, the load feedback pressure of the LS type charging valve 14, the steering gear 3 and the on-board multi-way valve is fed back to the load sensitive pump 2 through the shuttle valve 4, so that the pressure and flow distribution control is realized, and the feedback oil path is shown in figure 4.
In this embodiment, the control valve may be an electromagnetic directional valve 13, a switching valve, a proportional valve, or a servo valve.
In this embodiment, the pressure detecting unit 13 is a pressure sensor or a pressure switch.
In this embodiment, the LS-type charging valve 14 is a single-circuit charging valve or a dual-circuit charging valve, and when the LS-type charging valve 14 is a single-circuit charging valve, the brake valve 7 is a single brake valve, corresponding to one brake accumulator 8; when the LS-type charging valve 14 is a dual-circuit charging valve, the brake valve 7 is a dual-brake valve, and corresponds to two brake accumulators 8, as shown in fig. 1, the port A1 of the LS-type charging valve 14 is simultaneously connected to one of the brake accumulators 8 and the brake valve 7, and the port A2 is simultaneously connected to the other brake accumulator 8 and the brake valve 7. The brake accumulator 8 supplies brake pressure oil to the brake actuator via the brake valve 7.
In this embodiment, the oil outlet of the load-sensitive pump 2 is also connected to the hydraulic tank 1 via a relief valve 9.
In this embodiment, the diverter 3, the LS-type charging valve 14 and the brake valve 7 each have a T-port (i.e., a relief valve return port), and the T-ports of the diverter 3, the LS-type charging valve 14 and the brake valve 7 are connected to the hydraulic tank 1.
In this embodiment, the system further includes an alarm connected to the controller, and when the detected value of the pressure detecting unit 13 is abnormal (i.e., abnormally higher or lower than the preset pressure and does not automatically charge the brake accumulator 8), the alarm gives an alarm, or the related actions are limited while giving an alarm, so that the safety is ensured. Such as insufficient pressure and failure of the brakes, the walking action is restricted.
The working principle of the hydraulic control system of the utility model is as follows:
when the pressure of the brake accumulator 8 detected by the pressure detection unit 13 is lower than the preset pressure, the electromagnetic directional valve 13 is electrified and cut off in a one-way, the load feedback pressure cannot be unloaded from the steering gear 3, the load feedback pressure of the LS-type charging valve 14 acts on the spring cavity side of the priority valve 5 and is fed back to the load-sensitive pump 2 through the shuttle valve 4, the priority valve 5 is in a right working position, the brake accumulator 8 is charged by the displacement change of the load-sensitive pump 2 through the LS-type charging valve 14 until the pressure of the brake accumulator 8 detected by the pressure detection unit 13 is higher than the preset pressure, the LS-type charging valve 14 is switched over, the electromagnetic directional valve 13 is in power-off conduction, the load feedback pressure is communicated with the hydraulic oil tank 1, the charging is ended, the priority valve 5 is restored to the left working position, and the load-sensitive pump 2 is restored to a low-pressure standby state. When the pressure of the brake accumulator 8 is reduced to be lower than the preset pressure due to the operation of the brake valve 7, the electromagnetic reversing valve 13 is electrified to be cut off in a one-way mode, the load-sensitive pump 2 charges the brake accumulator 8 through the LS type charging valve 14, and the brake accumulator 8 is ensured to always maintain the brake reserve pressure.
According to the utility model, the power-off of the electromagnetic reversing valve 13 is controlled by the pressure of the brake accumulator 8 detected by the pressure detection unit 13, so that whether the charging feedback pressure and the load feedback pressure of the steering gear 3 are at the neutral position or not is controlled, the load feedback pressure can be unloaded during standby and cannot always overflow at high pressure, thus the brake accumulator 8 can be charged normally without holding pressure during standby, the pressure value of the brake accumulator 8 is in a normal range, and the brake accumulator 8 is ensured to always keep the brake reserve pressure; the pressure detection unit 13 is adopted to monitor the pressure of the liquid filling loop in real time, so that the safety and reliability of the system are ensured.
When the steering gear 3 is operated, or the on-vehicle multi-way valve is operated, or the steering gear 3 and the on-vehicle multi-way valve are operated simultaneously, the load feedback pressure of the steering gear 3 and the on-vehicle multi-way valve is fed back to the feedback oil port of the load sensitive pump 2 through the shuttle valve 4, the load sensitive pump 2 supplies oil to the steering gear 3 and the on-vehicle multi-way valve, and the flow distribution is carried out through the priority valve 5, so that the priority of steering flow is ensured. When the multiple actions are performed simultaneously, steering and braking liquid filling are prioritized.
According to the utility model, the load-sensitive pump 2 is adopted to supply oil to the steering system, the travelling brake system and the on-vehicle multi-way valve system, so that a separate liquid filling loop power source is omitted, a liquid filling loop and a pipeline are simplified, 2 central rotary joint channels are saved for the rotary forklift, and the overall cost is reduced.
The foregoing disclosure is merely illustrative of specific embodiments of the present utility model, but the scope of the present utility model is not limited thereto, and any person skilled in the art will readily recognize that changes and modifications are possible within the scope of the present utility model.
Claims (8)
1. A hydraulic control system comprises a load sensitive pump, a hydraulic oil tank, a steering gear, a priority valve, an LS type liquid filling valve, a brake energy accumulator and a pressure detection unit; the load-sensitive pump is driven by the driving mechanism, an oil inlet of the load-sensitive pump is connected with the hydraulic oil tank, an oil outlet of the load-sensitive pump is connected with a P port of the priority valve, a CF port of the priority valve is connected with a P port of the steering gear, and an A port of the LS type liquid filling valve is simultaneously connected with an oil inlet end of the brake energy accumulator and an oil inlet end of the brake valve; the method is characterized in that:
the system also comprises a control valve and a one-way valve, wherein the CF port of the priority valve is also connected with the P port of the LS type liquid filling valve; the LS port of the LS type liquid filling valve is connected with the feedback oil port of the load sensitive pump through a one-way valve and a shuttle valve in sequence, the LS port of the priority valve is connected with the feedback oil path between the one-way valve and the shuttle valve, and the LS port of the steering gear is connected with the feedback oil path between the one-way valve and the shuttle valve through a control valve; the pressure detection unit is arranged at the SW port of the LS type charging valve and is used for detecting the pressure of the brake accumulator, and the action of the control valve is controlled by the controller according to the detection value of the pressure detection unit.
2. The hydraulic control system of claim 1, wherein: the control valve is one of an electromagnetic reversing valve, a switching valve, a proportional valve and a servo valve.
3. The hydraulic control system of claim 1, wherein: the pressure detection unit is a pressure sensor or a pressure switch.
4. The hydraulic control system of claim 1, wherein: the LS type charging valve is a single-loop charging valve or a double-loop charging valve, and when the LS type charging valve is a single-loop charging valve, the brake valve is a single brake valve; when the LS-type charging valve is a double-loop charging valve, the brake valve is a double brake valve.
5. The hydraulic control system of claim 1, wherein: and an oil outlet of the load sensitive pump is also connected with the hydraulic oil tank through an overflow valve.
6. The hydraulic control system of claim 1, wherein: the steering gear, the LS type charging valve and the brake valve are all provided with T ports, and the T ports of the steering gear, the LS type charging valve and the brake valve are all connected with the hydraulic oil tank.
7. The hydraulic control system according to any one of claims 1 to 6, characterized in that: the system also comprises an alarm connected with the controller, and when the detection value of the pressure detection unit is abnormal, the alarm gives an alarm or limits actions while giving an alarm.
8. A high forklift truck, characterized in that it comprises a hydraulic control system according to any one of claims 1 to 7.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202322222620.7U CN220248509U (en) | 2023-08-18 | 2023-08-18 | High-order forklift and hydraulic control system thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202322222620.7U CN220248509U (en) | 2023-08-18 | 2023-08-18 | High-order forklift and hydraulic control system thereof |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN220248509U true CN220248509U (en) | 2023-12-26 |
Family
ID=89265998
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202322222620.7U Active CN220248509U (en) | 2023-08-18 | 2023-08-18 | High-order forklift and hydraulic control system thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN220248509U (en) |
-
2023
- 2023-08-18 CN CN202322222620.7U patent/CN220248509U/en active Active
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