CN212479728U - Pilot working hydraulic system of single-pump oil source - Google Patents
Pilot working hydraulic system of single-pump oil source Download PDFInfo
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- CN212479728U CN212479728U CN202020999697.9U CN202020999697U CN212479728U CN 212479728 U CN212479728 U CN 212479728U CN 202020999697 U CN202020999697 U CN 202020999697U CN 212479728 U CN212479728 U CN 212479728U
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Abstract
The utility model relates to a pilot working hydraulic system of single pump oil source, belong to the hydraulic pressure field, a serial communication port, including the working pump, the oil inlet is connected the working oil tank, the oil-out is connected with from relief pressure valve and balanced valve respectively, from the relief pressure valve exit linkage with the check valve, the check valve export is divided into two the tunnel, be connected with energy accumulator and spiller handle respectively, balanced valve access connection working pump export, the exit linkage multiple unit valve, the balanced valve establishes the control signal mouth, balanced valve control signal mouth connects shuttle valves group, multiple unit valve P mouth connects the balanced valve export, the control hydraulic fluid port is connected with the spiller handle, the working hydraulic fluid port is connected with the working oil cylinder, the spiller handle is equipped with pressure delivery outlet K1, K3, K2, K4, and connect the; the problem of the guide system continuous overflow generate heat and energy loss is solved to spare parts such as guide pump, overflow valves, oil cooler and pipeline are saved from the system structure to the purpose of optimizing complete machine overall arrangement, reduction in production manufacturing cost.
Description
Technical Field
The utility model relates to a hydraulic system field, concretely relates to guide's work hydraulic system in single pump oil source.
Background
At present, the control system of most engineering machinery working devices (such as bulldozers) consists of two major parts, namely a working hydraulic system and a pilot hydraulic system. The working pump and the pilot pump are respectively used as mutually independent pressure oil sources to provide the pressure oil sources for the working hydraulic system and the pilot hydraulic system, the pressure grade of the working hydraulic system is jointly controlled by the main safety valve and the middle position function of the working valve, when the working valve is in the middle position unloading function, the working hydraulic system is unloaded at low pressure and returns oil, and when the working valve is in a working state, the pressure grade of the working hydraulic system is controlled by the main overflow valve. The pilot system is composed of an overflow valve bank, a pilot handle and the like, pressure is controlled by the overflow valve bank, when the pilot handle does not work, the pilot handle is cut off, and oil of the pilot hydraulic system overflows through the overflow valve bank. The heat generated by the overflow of the overflow valve group must be cooled by the oil cooler so as to reach the thermal equilibrium state of the pilot hydraulic system. The structural design not only causes the waste of energy in the running process of the whole machine, but also increases the manufacturing cost of the whole machine.
Fig. 1 is a hydraulic schematic diagram of a conventional work implement control system for a bulldozer, which is analyzed for an operation state:
1. when the bulldozer is working, the duplex pump 01 works to suck oil from the working oil tank and output the set pressure and flow. The oil of the pilot hydraulic system respectively flows to the energy accumulator 06 and the handle 07 through the one-way valve 02, the pressure is controlled by the overflow valve 03, and when the system pressure reaches or is higher than the set pressure of the overflow valve 03 by 2.5MPa, the overflow valve starts to overflow. The overflow valve drainage is cooled by the oil cooler 04 to balance the heat generated by the overflow of the overflow valve 03. The function of the non-return valve 09 is to protect the oil cooler from excessive pressure. The energy accumulator 06 and the one-way valve 02 have the function of ensuring the transient pressure supply of the handle after the complete machine is flamed out so as to control the bulldozer working device to freely descend to the ground and the like. The stop valve 05 can control the opening and closing of an oil path from the duplex pump 01 to the pilot handle 07, so that the pilot handle 07 is in an unlocking or locking state. When the stop valve 05 is opened, the oil passages of the duplex pump 01 and the energy accumulator 06 to the pilot handle 07 are communicated, the pilot handle 07 is in an unlocking state, and otherwise, the pilot handle 07 is in a locking state.
2. The existing pilot handle 07 structure is a pressure reducing valve structure, when the pilot handle 07 is operated to act, a pressure output port corresponding to the pilot handle 07 outputs a set pressure to control the action of a hydraulic control multi-way valve so as to enable a bulldozer working device to work; when the pilot handle 07 does not act, the oil circuit of the pilot handle 07 is in a cut-off state, and the oil of the pilot hydraulic system overflows through the overflow valve 03 and is led to the oil cooler 04 to cool heat generated by the overflow of the overflow valve 03.
3. According to statistics, the time for operating the pilot handle only accounts for about 20% of the working time of the whole machine, the rest 80% of the working time, and the pilot hydraulic system is in a state that the overflow valve overflows and flows through the oil cooler for cooling, so that continuous energy waste is caused.
SUMMERY OF THE UTILITY MODEL
The utility model aims to solve the technical problem that to prior art not enough, provide a guide's work hydraulic system in single pump oil source, effectively solve guide's system and last the overflow and generate heat and energy loss's problem to from spare parts such as the structural saving guide's pump of system, overflow valves, oil cooler and pipeline, optimize the complete machine overall arrangement, reduce manufacturing cost.
The utility model provides an above-mentioned technical problem's technical scheme as follows: a pilot working hydraulic system of a single-pump oil source is characterized by comprising
The oil inlet of the working pump is connected with a working oil tank, the oil outlet of the working pump is divided into two paths which are respectively connected with a self-reducing valve and a balance valve,
the outlet of the self-reducing valve is connected with a one-way valve,
the outlet of the one-way valve is divided into two paths which are respectively connected with an energy accumulator and a scraper knife handle, the energy accumulator is used as an auxiliary power source of the scraper knife handle to keep the pressure of the system,
the inlet of the balance valve is connected with the outlet of the working pump, the outlet of the balance valve is connected with the multi-way valve, the balance valve is provided with a control signal port, the control signal port of the balance valve is connected with a shuttle valve group,
a P port of the multi-way valve is connected with an outlet of the balance valve, a control oil port of the multi-way valve is connected with a scraper knife handle, a working oil port of the multi-way valve is connected with a working oil cylinder,
the scraper knife handle is provided with pressure output ports K1, K3, K2 and K4 and is respectively connected with a control oil port of the multi-way valve;
and a signal pressure input port of the shuttle valve group is connected with a pressure output port of the scraper knife handle, and a signal pressure output port of the shuttle valve group is connected with a control signal port of the balance valve.
Further, the working oil cylinder comprises a scraper blade inclined oil cylinder, a scraper blade lifting oil cylinder left side and a scraper blade lifting oil cylinder right side.
Further, the multi-way valve is provided with a working oil port A1, a working oil port B1, a working oil port A2 and a working oil port B2, the working oil port A1 of the multi-way valve is connected with a rod cavity of the shovel blade tilting oil cylinder, the working oil port B1 of the multi-way valve is connected with a rodless cavity of the shovel blade tilting oil cylinder, a working oil port A2 of the multi-way valve is connected with a rod cavity on the left side of the shovel blade lifting oil cylinder and a rod cavity on the right side of the shovel blade lifting oil cylinder, and a working oil port B2 of the multi-way valve is connected with a.
Further, the multi-way valve is provided with control oil ports C1, C3, C2 and C4, and the multi-way valve control oil ports C1, C3, C2 and C4 are respectively connected with pressure output ports K1, K3, K2 and K4 of the scraper knife handle.
Further, the shuttle valve group comprises shuttle valves X11, X12 and X21, a signal input port of the shuttle valve X11 is respectively connected with pressure output ports K1 and K3 of the scraper knife handle, a signal input port of the shuttle valve X12 is respectively connected with pressure output ports K2 and K4 of the scraper knife handle, a signal input port of the shuttle valve X21 is respectively connected with signal output ports of the shuttle valve X11 and the shuttle valve X12, and a signal output port of the shuttle valve X21 is connected with a control signal port of the balance valve.
Further, the T port of the multi-way valve returns oil to a working oil tank.
Furthermore, the oil-return filter is also included, the inlet of the oil-return filter is connected with the T port of the multi-way valve, and the outlet of the oil-return filter is connected with the working oil tank.
The utility model has the advantages that:
1. the utility model realizes the respective control of different pressure levels of a single pump source through the connection relation of all the parts, realizes the automatic pressure relief of the pilot system through the automatic diagnosis function of the handle action and the pressure and flow of the working pump which is required to be opened and closed by the balance valve, and can effectively solve the problems of continuous overflow heating and energy loss of the pilot system;
2. the utility model discloses can follow the structural spare parts such as guide's pump, overflow valves, oil cooler and pipeline of economizing of system, optimize the complete machine overall arrangement, reduce production manufacturing cost.
Drawings
FIG. 1 is a schematic diagram of a prior art hydraulic system;
FIG. 2 is a schematic diagram of the hydraulic system of the present invention;
in the figure: 01. the system comprises a duplex pump, 02, a one-way valve, 03, an overflow valve, 04, an oil cooler, 05, a stop valve, 06, an energy accumulator, 07, a handle, 08, a multi-way valve and 09, a one-way valve; 1. the hydraulic shovel comprises a working oil tank, 2 a working pump, 3A an automatic pressure reducing valve, 3B a balance valve, 4 a multi-way valve, 5 a shuttle valve group, 6 a shovel blade handle, 7 an oil return filter, 8 a one-way valve, 9 an energy accumulator, 10 a stop valve, 11 a shovel blade tilting oil cylinder, 12 a shovel blade lifting oil cylinder and 13 a shovel blade lifting oil cylinder.
Detailed Description
The principles and features of the present invention will be described with reference to the drawings, which are provided for illustration purposes only and are not intended to limit the scope of the present invention.
As shown in fig. 2, the pilot-operated hydraulic system of the single-pump oil source of the present embodiment includes
An oil inlet of the working pump 2 is connected with a working oil tank 1, an oil outlet thereof is divided into two paths which are respectively connected with a self-reducing valve 3A and a balance valve 3B,
the outlet of the self-pressure reducing valve 3A is connected with a one-way valve 8; an inlet of the self-pressure reducing valve 3A is connected with an outlet of the working pump 2, an outlet of the self-pressure reducing valve 3A is connected with a pilot system, the set pressure is 3.9MPa, and the safety protection overflow pressure is 4.9 MPa; when the pressure of the outlet of the self-reducing valve (3A) does not reach the set pressure of 3.9MPa, the self-reducing valve (3A) is opened, a pilot system can ask for the pressure and the flow of the working pump, when the pressure of the outlet of the self-reducing valve (3A) reaches the set pressure of 3.9MPa, the self-reducing valve (3A) is closed, and the flow of the working pump supplies oil to the multi-way valve (4) through the balance valve (3B);
the outlet of the one-way valve 8 is divided into two paths, which are respectively connected with an energy accumulator 9 and a scraper knife handle 6, the function of the one-way valve is that the energy accumulator 9 can be used as an auxiliary power source of the scraper knife handle 6 to keep the system pressure,
an inlet of the balance valve 3B is connected with an outlet of the working pump 2, an outlet of the balance valve 3B is connected with a multi-way valve 4, the balance valve 3B is provided with a control signal port, the control signal port of the balance valve 3B is connected with a shuttle valve group 5,
a port P of the multi-way valve 4 is connected with an outlet of the balance valve 3B, a control oil port of the multi-way valve 4 is connected with a scraper knife handle 6, a working oil port of the multi-way valve 4 is connected with a working oil cylinder, and the working oil cylinder comprises a scraper knife inclined oil cylinder 11, a scraper knife lifting oil cylinder left 12 and a scraper knife lifting oil cylinder right 13;
specifically, the multi-way valve 4 is provided with working oil ports A1, B1, A2 and B2, the working oil port A1 of the multi-way valve 4 is connected with a rod cavity of the scraper knife inclined oil cylinder 11, the working oil port B1 of the multi-way valve 4 is connected with a rodless cavity of the scraper knife inclined oil cylinder 11, the working oil port A2 of the multi-way valve 4 is connected with a rod cavity of the left 12 of the scraper knife lifting oil cylinder and a rod cavity of the right 13 of the scraper knife lifting oil cylinder, and the working oil port B2 of the multi-way valve 4 is connected with a rodless cavity of the left 12 of the scraper knife lifting oil cylinder and a;
the multi-way valve 4 is provided with control oil ports C1, C3, C2 and C4, and the control oil ports C1, C3, C2 and C4 of the multi-way valve are respectively connected with pressure output ports K1, K3, K2 and K4 of the scraper knife handle 6
The scraper knife handle 6 is provided with a stop valve 10 on an oil inlet pipeline, the scraper knife handle 6 is provided with pressure output ports K1, K3, K2 and K4, and the pressure output ports K1, K3, K2 and K4 are respectively connected with a control oil port of the multi-way valve 4;
a signal pressure input port of the shuttle valve group 5 is connected with a pressure output port of the scraper knife handle 6, and a signal pressure output port of the shuttle valve group 5 is connected with a control signal port of the balance valve;
specifically, the shuttle valve group 5 comprises shuttle valves X11, X12 and X21, wherein a signal input port of the shuttle valve X11 is respectively connected with pressure output ports K1 and K3 of the scraper knife handle 6, a signal input port of the shuttle valve X12 is respectively connected with pressure output ports K2 and K4 of the scraper knife handle 6, a signal input port of the shuttle valve X21 is respectively connected with signal output ports of the shuttle valve X11 and the shuttle valve X12, and outputs a pressure signal "Ls = K1 or K2 or K3 or K4", and a signal output port of the shuttle valve X21 is connected with a control signal port of the balance valve 3B; assuming that the output signal pressure of the shuttle valve group 5 is Ls MPa, the opening pressure of the balance valve 3B is (Ls +0.3 MPa).
And an inlet of the oil return filter 7 is connected with the multi-way valve 4T port, an outlet of the oil return filter 7 is connected with the working oil tank 1, and the multi-way valve 4T port returns oil to the working oil tank 1 through the oil return filter 7.
The utility model discloses a hydraulic pressure principle is as shown in figure 2, bull-dozer work hydraulic system and guide's hydraulic system are supplied oil by working pump 2, and work hydraulic system pressure is controlled by 4 inside main relief valves of working valve, sets for 21MPa, and when working valve 4 was in operating condition, work hydraulic system pressure level was decided by main overflow valve or work load, under the majority condition, because the pressure that work load produced is less than main relief valve settlement pressure 21MPa, main relief valve can not be in for a long time and open overflow state. When the working valve 4 does not work, the oil in the working hydraulic system can be unloaded and returned at lower pressure through the middle unloading function of the working valve 4, and no redundant energy waste is generated;
the pressure of the pilot hydraulic system is controlled by the one-way valve 8, the energy accumulator 9, the pilot handle 6, the shuttle valve group 5, the self-reducing valve 3A and the balance valve 3B together. The one-way valve 8 and the energy accumulator 9 are used as an auxiliary power source to keep the system pressure, so that the pilot handle 6 can normally act in a short time; the shuttle valve group 5 is equivalent to a valve of a plurality of check valve combinations, and functions as an or gate, and the opening pressure of the balance valve 3B is set to the sum of the output pressure "Ls" of the shuttle valve group 5 and 0.3 MPa.
When the pilot handle 6 does not act, the pressure output of the shuttle valve group 5 is 0, the opening pressure of the balance valve 3B is (0 + 0.3) MPa, the oil source leads to the multi-way valve 4 at the low pressure of 0.3MPa, the multi-way valve 4 is in a neutral position function, and the oil source is unloaded back to the working oil tank 1 at the low pressure through the neutral position function of the multi-way valve 4;
when the pilot handle 6 acts, pressure output is provided for any pressure output port, and if the pressure value is Ls MPa, the shuttle valve group 5 detects the pressure value through the OR gate function and transmits the Ls MPa to the balance valve 3B, the opening pressure of the balance valve (3B) is controlled to be (Ls + 0.3) MPa, and the maximum value of Ls is the set pressure of 3.9MPa of the self-pressure reducing valve 3A. When the pressure of an oil path before the balance valve 3B is controlled is lower than the opening pressure (Ls + 0.3) MPa of the balance valve 3B, the oil source flows through the self-reducing valve 3A, the one-way valve 8, the energy accumulator 9 and the pilot handle 6 until the system pressure is adjusted to the set pressure 3.9MPa by the self-reducing valve (3A), the self-reducing valve 3A is closed, the system pressure continues to rise until the pressure reaches the opening pressure (3.9 + 0.3) MPa of the balance valve 3B, the balance valve 3B is opened, the oil path flows to the working valve 4, and oil is supplied to the working valve 4. At the moment, the working pump 2 supplies oil to the pilot system at the flow rate required by the action of the pilot handle 6 and the pressure of 3.9MPa, ensures the oil supply of the multi-way valve 4 of the main system, and realizes the pilot working hydraulic systems with different pressure grades, which have the low-pressure unloading function and act on a single oil source.
The utility model discloses a hydraulic system is as single oil supply by the working pump, supplies with working hydraulic system and guide's hydraulic system simultaneously. The pressure grade of the working hydraulic system is controlled by the main safety valve and the middle position machine of the working valve together; the pressure grade of the pilot hydraulic system is controlled by a self-reducing valve, a balance valve and a shuttle valve together, the opening and the closing of the balance valve are controlled by a shuttle valve group by utilizing a hydraulic oil source provided by a working pump, when a handle works, the balance valve detects the output pressure of the handle under the action of the shuttle valve and is continuously closed, the pressure is adjusted to a set pressure by the self-reducing valve, when the handle does not act, the balance valve is opened, the working valve is in a middle position function, and the oil source can unload at low pressure to return to an oil tank through the middle position function of the working valve. The hydraulic system can avoid energy loss in the operation process of the whole machine, save a pilot pump, an overflow valve group, an oil cooler and a pipeline from the structure and reduce the cost of the whole machine.
Claims (7)
1. A pilot working hydraulic system of a single-pump oil source is characterized by comprising
An oil inlet of the working pump (2) is connected with a working oil tank (1), an oil outlet of the working pump is divided into two paths which are respectively connected with a self-reducing valve (3A) and a balance valve (3B),
a self-reducing valve (3A), the outlet of which is connected with a one-way valve (8),
the outlet of the one-way valve (8) is divided into two paths, the two paths are respectively connected with an energy accumulator (9) and a scraper knife handle (6), the energy accumulator (9) is used as an auxiliary power source of the scraper knife handle (6) to keep the pressure of the system,
an inlet of the balance valve (3B) is connected with an outlet of the working pump (2), an outlet of the balance valve is connected with a multi-way valve (4), the balance valve (3B) is provided with a control signal port, the control signal port of the balance valve (3B) is connected with a shuttle valve group (5),
a P port of the multi-way valve (4) is connected with an outlet of the balance valve (3B), a control oil port of the multi-way valve (4) is connected with a scraper knife handle (6), a working oil port of the multi-way valve (4) is connected with a working oil cylinder,
the oil inlet pipeline of the scraper knife handle (6) is provided with a stop valve (10), and the scraper knife handle (6) is provided with pressure output ports K1, K3, K2 and K4 which are respectively connected with a control oil port of the multi-way valve (4);
and a signal pressure input port of the shuttle valve group (5) is connected with a pressure output port of the scraper knife handle (6), and a signal pressure output port of the shuttle valve group (5) is connected with a control signal port of the balance valve.
2. The pilot working hydraulic system of a single pump oil source according to claim 1, characterized in that the working cylinders include a blade tilting cylinder (11), a blade lifting cylinder left (12) and a blade lifting cylinder right (13).
3. The pilot-operated hydraulic system of a single-pump oil source as claimed in claim 2, wherein the multi-way valve (4) is provided with operating oil ports a1, B1, a2 and B2, the multi-way valve operating oil port a1 is connected with the rod cavity of the blade tilt cylinder (11), the multi-way valve operating oil port B1 is connected with the rodless cavity of the blade tilt cylinder (11), the multi-way valve operating oil port a2 is connected with the rod cavity of the left (12) of the blade lift cylinder and the rod cavity of the right (13) of the blade lift cylinder, and the multi-way valve operating oil port B2 is connected with the rodless cavity of the left (12) of the blade lift cylinder and the rodless cavity of the right (13) of the blade lift cylinder.
4. The pilot working hydraulic system of a single-pump oil source as claimed in claim 1, wherein the multi-way valve (4) is provided with control ports C1, C3, C2 and C4, and the multi-way valve control ports C1, C3, C2 and C4 are respectively connected with pressure output ports K1, K3, K2 and K4 of a scraper knife handle (6).
5. The pilot operated hydraulic system of a single pump oil source according to claim 1, characterized in that the shuttle valve group (5) comprises shuttle valves X11, X12, X21, signal input ports of the shuttle valve X11 are respectively connected to pressure output ports K1 and K3 of the shovel handle (6), signal input ports of the shuttle valve X12 are respectively connected to pressure output ports K2 and K4 of the shovel handle (6), signal input ports of the shuttle valve X21 are respectively connected to signal output ports of the shuttle valve X11 and the shuttle valve X12, and a signal output port of the shuttle valve X21 is connected to a control signal port of the balancing valve (3B).
6. Pilot working hydraulic system of a single pump oil source according to claim 1, characterised in that the multi-way valve (4) T-port returns to the working oil tank (1).
7. The pilot working hydraulic system of a single-pump oil source according to claim 6, characterized by further comprising an oil return filter (7), wherein an inlet of the oil return filter (7) is connected with a T port of the multi-way valve (4), and an outlet of the oil return filter (7) is connected with the working oil tank (1).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202020999697.9U CN212479728U (en) | 2020-06-04 | 2020-06-04 | Pilot working hydraulic system of single-pump oil source |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202020999697.9U CN212479728U (en) | 2020-06-04 | 2020-06-04 | Pilot working hydraulic system of single-pump oil source |
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| Publication Number | Publication Date |
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| CN212479728U true CN212479728U (en) | 2021-02-05 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN202020999697.9U Active CN212479728U (en) | 2020-06-04 | 2020-06-04 | Pilot working hydraulic system of single-pump oil source |
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- 2020-06-04 CN CN202020999697.9U patent/CN212479728U/en active Active
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