CN219432175U - Hydraulic system and engineering machinery - Google Patents
Hydraulic system and engineering machinery Download PDFInfo
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- CN219432175U CN219432175U CN202320250912.9U CN202320250912U CN219432175U CN 219432175 U CN219432175 U CN 219432175U CN 202320250912 U CN202320250912 U CN 202320250912U CN 219432175 U CN219432175 U CN 219432175U
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Abstract
The utility model relates to a hydraulic system, which aims to solve the problem of driving an air conditioner compressor on the existing double-power engineering machinery, and constructs the hydraulic system and the engineering machinery, wherein the hydraulic system comprises a first hydraulic pump driven by an engine, a second hydraulic pump driven by a motor, a motor series oil circuit and a switching valve, and the motor series oil circuit comprises a fan motor in a heat dissipation system and a compressor motor in the air conditioner system; the first hydraulic pump and the second hydraulic pump are connected with two oil inlets of the switching valve, an oil outlet of the switching valve is connected with an oil inlet of the motor series oil circuit, and one oil outlet of the switching valve is selectively communicated with one of the two oil inlets. In the utility model, only one set of air conditioning system is needed to be configured on the double-power engineering machinery, so that the requirements of an engine mode and a motor working mode can be met, and compared with the prior art, the cost is reduced.
Description
Technical Field
The present utility model relates to a hydraulic system, and more particularly, to a hydraulic system and a construction machine.
Background
In the construction machinery, some direct driving components of the engine, such as an air conditioner compressor, are usually configured, and the engine is started to drive the compressor to operate, so that the air conditioner system works normally.
On a double-power working machine, there are two power devices, i.e., a diesel engine and an electric motor. The working mode of the double-power engineering machinery is a power-dragging mode of engine working or motor working, the engineering machinery can work by using the engine when the transition is needed, the normal operation is generally to use power-dragging, namely external industrial power is used, the working is performed by using a motor on the whole machine, and the cost of power-consumption operation is lower than that of diesel. When the hydraulic pump and other elements are directly driven by the motor to work, the engine is stopped, and at the moment, the air conditioner compressor which directly takes power from the diesel engine to work cannot work normally.
In order to solve the problem that the existing double-power engineering machinery cannot operate with an air-conditioning compressor directly driven by an engine in a power-dragging mode, two measures are generally adopted by the existing double-power engineering machinery lock, wherein one of the measures is provided with two air-conditioning systems, the compressor of one air-conditioning system is directly driven by the engine, and the compressor of the other air-conditioning system is driven by a motor; the second way is to provide two air conditioning compressors on the machine, both driven by the engine and motor, respectively, operating in the engine mode and in the electric traction mode.
Disclosure of Invention
The utility model aims to solve the technical problem of driving an air conditioner compressor on the existing double-power engineering machinery, and provides a hydraulic system and engineering machinery, so that the cost related to the air conditioner system is reduced.
The technical scheme for achieving the purpose of the utility model is as follows: the hydraulic system is used for double-power engineering machinery and is characterized by comprising a first hydraulic pump driven by an engine, a second hydraulic pump driven by a motor, a motor series oil circuit and a switching valve, wherein the motor series oil circuit comprises a fan motor in a heat dissipation system and a compressor motor in an air conditioning system; the first hydraulic pump and the second hydraulic pump are connected with two oil inlets of the switching valve, an oil outlet of the switching valve is connected with an oil inlet of the motor series oil circuit, and one oil outlet of the switching valve is selectively communicated with one of the two oil inlets.
The hydraulic system is used for the double-power engineering machinery, and the requirements of the engine mode and the motor working mode can be met only by configuring one set of air conditioning system, so that the cost is reduced compared with the prior art.
In the hydraulic system, the switching valve is a shuttle valve or a two-position three-way reversing control valve.
In the hydraulic system, the motor series oil way further comprises a fan motor control valve for controlling the positive and negative rotation of a fan motor, a compressor motor control valve for controlling the start and stop of a compressor motor, an oil return cooling unit and an oil return filtering unit; the fan motor control valve is a two-position four-way valve, the compressor motor control valve is a two-position two-way valve, an oil outlet of the switching valve is connected with an oil inlet of the fan motor control valve, and an oil return port of the fan motor control valve is connected with a hydraulic oil tank sequentially through the oil return cooling unit and the oil return filtering unit; the fan motor and the compressor motor are connected in series between two working oil ports of the fan motor control valve, and the compressor motor control valve is connected with the compressor motor in parallel. Or the motor series oil way also comprises a fan motor control valve used for controlling the positive and negative rotation of the fan motor, a compressor motor control valve used for controlling the start and stop of the compressor motor, a one-way valve, an oil return cooling unit and an oil return filtering unit; the fan motor control valve is a two-position four-way valve, and the compressor motor control valve is a two-position three-way valve; the oil return port of the fan motor control valve is connected with a hydraulic oil tank through the oil return cooling unit and the oil return filtering unit in sequence; an oil outlet of the switching valve is connected with an oil inlet of a compressor motor control valve, a first oil outlet of the compressor motor control valve is connected with an oil inlet of the compressor motor, an oil outlet of the compressor motor is connected with an oil inlet of the one-way valve, and an oil outlet of the one-way valve and a second oil outlet of the compressor motor control valve are both connected with an oil inlet of the fan motor control valve; and one oil inlet of the compressor motor control valve is communicated with the first oil outlet or the second oil outlet.
In the hydraulic system, the fan motor control valve and the compressor motor control valve are electromagnetic valves. Further, the hydraulic system also includes a controller, with which the fan motor control valve and the compressor motor control valve are electrically connected.
In the hydraulic system, the hydraulic system further comprises a second one-way valve, an oil inlet of the second one-way valve is connected with an oil return port of the fan motor control valve, and an oil outlet of the second one-way valve is connected with an oil inlet of the fan motor control valve.
In the hydraulic system, the oil return cooling unit comprises a radiator, a first back pressure valve and a second back pressure valve which are connected in series with the radiator, an oil return port of the control valve is simultaneously connected with an oil inlet of the second back pressure valve and an oil inlet of the first back pressure valve, and an oil outlet of the second back pressure valve and an oil outlet of the radiator are both connected with the oil return filtering unit.
In the hydraulic system, the return oil filtering unit consists of a return oil filter and an overflow valve connected with the return oil filter in parallel.
The technical scheme for achieving the purpose of the utility model is as follows: the construction engineering machine is characterized by comprising the hydraulic system, wherein the fan motor is connected with the cooling fan for driving the cooling fan to rotate, and the compressor motor is connected with the air conditioner compressor for driving the air conditioner compressor to rotate.
Compared with the prior art, the utility model can reduce the cost compared with the prior art by only configuring one set of air conditioning system on the double-power engineering machinery to meet the requirements of an engine mode and a motor working mode.
Drawings
Fig. 1 is a schematic diagram of a hydraulic system according to an embodiment of the present utility model.
Fig. 2 is a schematic diagram of two hydraulic systems according to an embodiment of the utility model.
Part names and serial numbers in the figure:
the hydraulic oil tank 1, the engine 2, the first hydraulic pump 3, the motor 4, the second hydraulic pump 5, the switching valve 6, the second check valve 7, the fan motor control valve 8, the compressor motor control valve 9, the fan motor 10, the compressor motor 11, the return oil cooling unit 12, the radiator 121, the first back pressure valve 122, the second back pressure valve 123, the return oil filtering unit 13, the oil filter 131, the relief valve 132, the check valve 14, and the controller 15.
Detailed Description
The following describes specific embodiments with reference to the drawings.
Embodiment one.
Fig. 1 shows the principle of a hydraulic system on a double power engineering machine in accordance with a first embodiment of the present utility model. The double-power engineering machine can be an excavator, a grabbing machine, a loading machine and the like. The hydraulic system is used for driving and controlling a radiator fan in a radiator system on a machine and a compressor in an air conditioning system.
As shown in fig. 1, the hydraulic system includes a first hydraulic pump 3 driven by an engine 2, a second hydraulic pump 5 driven by an electric motor 4, a motor series oil passage, and a switching valve 6. The engine 2 and the motor 4 are two power components of the double-power engineering machinery and respectively work in different modes, wherein the engine 2 works when the machine is in transition or does not have access to a power grid to power the whole machine. When the engineering machinery is in operation, the motor 4 works when the electric power is acquired through the connection of the cable and the power grid, and provides power for the whole machine or part of functional modules such as an air conditioning system.
In this embodiment, the switching valve 6 is a shuttle valve, two oil inlet ends of which are respectively connected with the pump port of the first hydraulic pump 3 and the pump port of the second hydraulic pump 5, and oil suction ports of the two hydraulic pumps are connected with the hydraulic oil tank 1, and oil is sucked from the hydraulic oil tank. The oil outlet end of the switching valve 6 is connected with the oil inlet end of the motor series oil circuit.
The motor series oil passage includes a fan motor 10, a compressor motor 11, a fan motor control valve 8, a compressor motor control valve 9, an oil return cooling unit 12, an oil return filter unit 13, and the like.
The fan motor control valve 8 is a two-position four-way valve for controlling the forward and reverse rotation of the fan motor 10. The compressor motor control valve 9 is a two-position two-way valve for controlling the rotation and stop of the compressor motor 11. An oil outlet of the switching valve 6 is connected with an oil inlet of the fan motor control valve 8, and an oil return port of the fan motor control valve 8 is connected with the hydraulic oil tank 1 through an oil return cooling unit 12 and an oil return filtering unit 13 in sequence; the fan motor 10 and the compressor motor 11 are connected in series between the two working ports of the fan motor control valve 8, and the compressor motor control valve 9 is connected in parallel with the compressor motor 11. The fan motor control valve 8 and the compressor motor control valve 9 may be solenoid valves controlled by a controller outputting a control current.
An oil outlet of the second one-way valve 7 is connected with an oil inlet of the fan motor control valve 8, and an oil inlet of the second one-way valve 7 is connected with an oil return port of the fan motor control valve 8. When the flow of hydraulic oil supplied by the switching valve 6 is smaller than the flow required by the rotating speed of the fan motor 10, the oil in the oil return port of the fan motor control valve 8 enters the oil inlet of the fan motor control valve 7 through the second one-way valve 7 to supplement the oil to the fan motor 5.
The oil return cooling unit 12 comprises a radiator 121, a first back pressure valve 122 and a second back pressure valve 123 which are connected in series with the radiator 121, an oil return port of the fan motor control valve 8 is simultaneously connected with an oil inlet of the second back pressure valve 123 and an oil inlet of the first back pressure valve 122, and an oil outlet of the second back pressure valve 123 and an oil outlet of the radiator 121 are both connected with the oil return filtering unit 13.
The return filter unit 13 is composed of a return oil filter 131 and a relief valve 132 connected in parallel to the return oil filter 131, and outlets of the return oil filter 131 and the relief valve 132 are connected to the hydraulic tank 1.
In this embodiment, when the construction machine is operated in the engine mode, the motor 4 is in a stalled state, the engine 2 is operated to drive the first hydraulic pump 3, and the output pressure oil is supplied to the motor series oil passage through the switching valve 6 to drive the corresponding motor to rotate. When the engineering machinery works in a power dragging mode, the engine 2 is in a stalling state, the generator 4 works under the drive of electric power of the power grid to drive the second hydraulic pump 5, and output pressure oil is supplied to the motor series oil way through the switching valve 6 to drive the corresponding motor to rotate.
The compressor motor control valve 9 is in a conducting state when in a power-off state, the pressure of the working oil port A2 and the working oil port B2 of the compressor motor 11 is the same, and the compressor motor 11 is in a stalling state. The fan motor 10 may be rotated in either forward or reverse direction at this time. When the fan motor control valve 8 is powered off, an oil inlet P of the fan motor control valve is communicated with a working oil port A, the working oil port B is communicated with an oil return port, pressure oil flows to a working oil port A1 of the fan motor, flows out from the working oil port B1 and flows to the fan motor control valve through a compressor motor control valve, and the fan motor rotates positively; when the fan motor control valve 8 is powered on, an oil inlet P of the fan motor control valve is communicated with a working oil port B, the working oil port A is communicated with an oil return port, pressure oil flows to a working oil port B1 of the fan motor 10 through the compressor motor control valve 9, flows out of the working oil port A1 and flows to the fan motor control valve 8, and the fan motor 10 is reversely rotated; when the fan motor 10 is reversed, the radiator fan is driven to be reversed, dust and attached objects on the radiator are blown away, and the radiator is cleaned.
When both the compressor motor control valve 9 and the fan motor control valve 8 are powered, the pressure oil flows to the working oil port A1 of the fan motor 10, flows out from the working oil port B1, enters the working oil port A2 of the compressor motor 11, flows out from the working oil port B2 to the fan motor control valve 8, and both the fan motor 10 and the compressor motor 11 rotate forward. Since the air conditioner compressor does not have the function of reversing operation, the compressor motor control valve 9 must be de-energized and the compressor motor stopped when the fan motor 10 reverses to remove dust.
In this embodiment, only one set of air conditioning system is required to be configured on the construction machine, so that the air conditioning function can be realized in the engine mode and the power-off mode (motor working mode), thereby reducing the cost.
Embodiment two.
Fig. 2 shows the principle of the hydraulic system on the double power engineering machine in the second embodiment of the utility model.
As shown in fig. 2, the hydraulic system includes a first hydraulic pump 3 driven by the engine 2, a second hydraulic pump 5 driven by the motor 4, a motor series oil passage, and a switching valve 6.
In this embodiment, the switching valve 6 is a two-position three-way valve, two oil inlets of which are respectively connected with the pump port of the first hydraulic pump 3 and the pump port of the second hydraulic pump 5, and oil suction ports of which are connected with the hydraulic oil tank 1, and suck oil from the hydraulic oil tank 1. The oil outlet of the switching valve 6 is connected with the oil inlet end of the motor series oil circuit.
The motor series oil passage includes a fan motor 10, a compressor motor 11, a fan motor control valve 8, a compressor motor control valve 9, a check valve 14, an oil return cooling unit 12, an oil return filter unit 13, and the like.
The compressor motor control valve 9 is a two-position three-way electromagnetic valve, a first oil outlet of the two-position three-way electromagnetic valve is connected with an oil inlet A2 port of the compressor motor 11, an oil outlet B2 port of the compressor motor 11 is connected with an oil inlet of the one-way valve 14, and an oil outlet of the one-way valve 14 is communicated with a second oil outlet of the compressor motor control valve 9 and is connected with an oil inlet of the fan motor control valve 8 through a pipeline. In the compressor motor control valve 9, its oil inlet is alternatively communicated with the first oil outlet or with the second oil outlet.
The fan motor control valve 8 is a two-position four-way electromagnetic valve, an oil return port of the fan motor control valve is connected with the oil return cooling unit 12, and an oil outlet end of the oil return cooling unit 12 is connected with the hydraulic oil tank 1 through the oil return filtering unit 13.
The two working oil ports of the fan motor control valve 8 are respectively connected with a first working oil port A1 and a second working oil port B1 of the fan motor 10 through pipelines. When the fan motor control valve 8 is powered off, the fan motor 10 rotates forward, and when the fan motor control valve 8 is powered on, the fan motor control valve 8 commutates, and the fan motor 10 rotates backward.
An oil outlet of the second one-way valve 7 is connected with an oil inlet of the fan motor control valve 8, and an oil inlet of the second one-way valve 7 is connected with an oil return port of the fan motor control valve 8. When the flow of hydraulic oil supplied by the switching valve 6 is smaller than the flow required by the rotating speed of the fan motor 10, the oil in the oil return port of the fan motor control valve 8 enters the oil inlet of the fan motor control valve 8 through the second one-way valve 7 to supplement the oil to the fan motor 10.
The compressor motor control valve 9 and the fan motor control valve 8 are electrically connected with a controller 15, and the working positions thereof are controlled by a controller 10. When the compressor motor control valve 9 is powered on, the oil inlet of the compressor motor control valve 9 is communicated with the first oil outlet, and the fan motor 10 and the compressor motor 11 work simultaneously. When the compressor motor control valve 9 is powered off, the oil inlet of the compressor motor control valve 9 is communicated with the second oil outlet, the fan motor 10 rotates to work, and the compressor motor 11 does not work. When the compressor motor control valve 9 is de-energized, the compressor motor does not operate, but if the fan motor control valve 8 is not energized, the fan motor 10 is rotated in the forward direction; if the fan motor control valve 8 is powered, the fan motor 10 is reversed, i.e. the fan motor can be rotated in a forward and reverse direction either when the compressor motor is running or when it is stopped.
In the construction machine of the present embodiment, the fan motor 10 is connected to the radiator fan for driving the radiator fan to rotate, and the compressor motor 1 is connected to the air conditioner compressor for driving the air conditioner compressor to rotate.
In this embodiment, when the oil inlet of the compressor motor control valve 9 is connected to the first oil outlet, oil flows through the compressor motor 11 and then flows to the fan motor control valve 8 and the fan motor 10, and the fan motor 10 and the compressor motor 11 operate simultaneously. The fan motor 10 can be rotated forward or backward by reversing the fan motor control valve 8 when the compressor motor 11 is operated, thereby realizing no need of stopping the compressor motor 11 when the fan motor 10 is rotated backward.
When the oil inlet of the compressor motor control valve 9 is communicated with the second oil outlet, only the fan motor 10 works, the compressor motor 11 does not work, the one-way valve 14 can isolate the fluctuation impact of oil on the compressor motor 11, and the oil can be prevented from leaking through the compressor motor 11.
In this embodiment, the compressor motor 11 is connected to the fan motor control valve 8 through the check valve 14 and the pipeline, and when the components and pipelines of the hydraulic system are arranged on the construction machine, the compressor motor 11, the compressor motor control valve 9 and the check valve 14 may be arranged at one place, the fan motor control valve 8 and the fan motor 10 may be arranged at one place, the components at two positions are connected through a pipeline, the hydraulic pump is connected to the compressor motor control valve 9 through a pipeline, and the fan motor control valve 8 is connected to the return oil cooling unit 12 through a pipeline. The compressor motor and the fan motor can be flexibly arranged with fewer lines.
Claims (10)
1. The hydraulic system is used for a double-power engineering machine and is characterized by comprising a first hydraulic pump driven by an engine, a second hydraulic pump driven by a motor, a motor series oil circuit and a switching valve, wherein the motor series oil circuit comprises a fan motor in a heat dissipation system and a compressor motor in an air conditioning system; the first hydraulic pump and the second hydraulic pump are connected with two oil inlets of the switching valve, an oil outlet of the switching valve is connected with an oil inlet of the motor series oil circuit, and one oil outlet of the switching valve is selectively communicated with one of the two oil inlets.
2. The hydraulic system of claim 1, wherein the switching valve is a shuttle valve or a two-position three-way reversing control valve.
3. The hydraulic system of claim 1, wherein the motor series oil circuit further comprises a fan motor control valve for controlling forward and reverse rotation of a fan motor, a compressor motor control valve for controlling start and stop of a compressor motor, an oil return cooling unit, and an oil return filtering unit; the fan motor control valve is a two-position four-way valve, the compressor motor control valve is a two-position two-way valve, an oil outlet of the switching valve is connected with an oil inlet of the fan motor control valve, and an oil return port of the fan motor control valve is connected with a hydraulic oil tank sequentially through the oil return cooling unit and the oil return filtering unit; the fan motor and the compressor motor are connected in series between two working oil ports of the fan motor control valve, and the compressor motor control valve is connected with the compressor motor in parallel.
4. The hydraulic system of claim 1, wherein the motor series oil circuit further comprises a fan motor control valve for controlling forward and reverse rotation of a fan motor, a compressor motor control valve for controlling start and stop of a compressor motor, a check valve, an oil return cooling unit, and an oil return filtering unit; the fan motor control valve is a two-position four-way valve, and the compressor motor control valve is a two-position three-way valve; the oil return port of the fan motor control valve is connected with a hydraulic oil tank through the oil return cooling unit and the oil return filtering unit in sequence;
an oil outlet of the switching valve is connected with an oil inlet of a compressor motor control valve, a first oil outlet of the compressor motor control valve is connected with an oil inlet of the compressor motor, an oil outlet of the compressor motor is connected with an oil inlet of the one-way valve, and an oil outlet of the one-way valve and a second oil outlet of the compressor motor control valve are both connected with an oil inlet of the fan motor control valve; and one oil inlet of the compressor motor control valve is communicated with the first oil outlet or the second oil outlet.
5. The hydraulic system of claim 3 or 4, wherein the fan motor control valve and the compressor motor control valve are solenoid valves.
6. The hydraulic system of claim 5, further comprising a controller, wherein the fan motor control valve and the compressor motor control valve are each electrically connected to the controller.
7. The hydraulic system of claim 3 or 4, further comprising a second one-way valve, an oil inlet of the second one-way valve being connected to an oil return port of the fan motor control valve, an oil outlet of the second one-way valve being connected to an oil inlet of the fan motor control valve.
8. The hydraulic system according to claim 3 or 4, wherein the oil return cooling unit comprises a radiator, a first back pressure valve and a second back pressure valve which are connected in series with the radiator, an oil return port of the control valve is simultaneously connected with an oil inlet of the second back pressure valve and an oil inlet of the first back pressure valve, and an oil outlet of the second back pressure valve and an oil outlet of the radiator are both connected with the oil return filtering unit.
9. The hydraulic system of claim 8, wherein the scavenge filter unit is comprised of a scavenge oil filter and a relief valve connected in parallel with the scavenge oil filter.
10. A construction machine characterized by having the hydraulic system according to any one of claims 1 to 9, the fan motor being connected to the radiator fan for driving the radiator fan in rotation, and the compressor motor being connected to the air conditioner compressor for driving the air conditioner compressor in rotation.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202320250912.9U CN219432175U (en) | 2023-02-20 | 2023-02-20 | Hydraulic system and engineering machinery |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202320250912.9U CN219432175U (en) | 2023-02-20 | 2023-02-20 | Hydraulic system and engineering machinery |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN219432175U true CN219432175U (en) | 2023-07-28 |
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ID=87338479
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202320250912.9U Active CN219432175U (en) | 2023-02-20 | 2023-02-20 | Hydraulic system and engineering machinery |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN219432175U (en) |
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2023
- 2023-02-20 CN CN202320250912.9U patent/CN219432175U/en active Active
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