Hydraulic control system, fire truck, and fire truck operation standby control method

Abstract

The present invention provides a hydraulic control system, a fire truck, and a control method for the standby operation of a fire truck. The hydraulic control system includes: a hydraulic actuator; a hydraulic oil pump, which is connected to the hydraulic actuator through an oil supply line; a first reversing valve, which is arranged on the oil supply line; a standby oil line, one end of which is communicated with the oil supply line and the other end is communicated with an oil tank; and a second reversing valve, which is arranged on the standby oil line. The hydraulic control system provided by the present invention has a standby state and a working state of the hydraulic actuator. In the standby state, the hydraulic oil pump is controlled to be turned on, and the hydraulic oil in the oil tank is supplied to the standby oil line. The hydraulic oil in a low-pressure and small-flow state circulates in the oil supply line and the standby oil line, and at the same time, this internal circulation oil line also has the function of heat dissipation. When the hydraulic actuator needs to work, it can enter the working state of the hydraulic actuator, improving the response efficiency of the hydraulic control system, and is particularly suitable for working conditions where the hydraulic actuator needs to respond as soon as possible.

Description

Technical Field

[0001] The present invention relates to the technical field of hydraulics, and in particular, to a hydraulic control system, a fire truck, and a control method for a fire truck during operation standby. Background Art

[0002] In a hydraulic system, by starting a hydraulic oil pump, the hydraulic oil in a fuel tank is conveyed to a hydraulic actuator in a high-pressure form. However, it takes a certain amount of time to pump out and pressurize the hydraulic oil in the fuel tank and then supply it to the hydraulic actuator, resulting in a certain response time for the existing hydraulic system and slow response speed of the hydraulic actuator.

[0003] For example, in the field of fire trucks, when a fire truck switches from a driving state to a water spraying state, the outriggers and booms of the fire truck need to be driven by a hydraulic system. The slow response of the hydraulic system will cause the fire truck to respond slowly and easily miss the best opportunity for fire extinguishing. Summary of the Invention

[0004] The present invention aims to solve at least one of the technical problems existing in the prior art.

[0005] To this end, a first aspect of the present invention provides a hydraulic control system, including: a hydraulic actuator; a hydraulic oil pump, which is connected to the hydraulic actuator through an oil supply line; a first reversing valve, which is arranged on the oil supply line and is located between the hydraulic oil pump and the hydraulic actuator; a standby oil line, one end of the standby oil line is communicated with the oil supply line, and the other end is communicated with the fuel tank. The connection point between the standby oil line and the oil supply line is located between the first reversing valve and the hydraulic oil pump; a second reversing valve, which is arranged on the standby oil line.

[0006] A second aspect of the present invention provides a fire truck.

[0007] A third aspect of the present invention provides a control method for a fire truck during operation standby.

[0008] In view of this, according to the first aspect of the present invention, a hydraulic control system is provided, including: a hydraulic actuator; a hydraulic oil pump, which is connected to the hydraulic actuator through an oil supply line; a first reversing valve, which is arranged on the oil supply line and is located between the hydraulic oil pump and the hydraulic actuator; a standby oil line, one end of the standby oil line is communicated with the oil supply line, and the other end is communicated with the fuel tank. The connection point between the standby oil line and the oil supply line is located between the first reversing valve and the hydraulic oil pump; a second reversing valve, which is arranged on the standby oil line.

[0009] The hydraulic control system provided by the present invention can have a standby state and a hydraulic actuator working state during operation. In the standby state, the first directional control valve is de-energized or commutated to disconnect the passage between the oil supply line and the hydraulic actuator, the second directional control valve is energized and commutated to connect the standby oil line, and the hydraulic oil pump is controlled to start, supplying the hydraulic oil in the fuel tank to the standby oil line. The hydraulic oil in the low-pressure and small-flow state circulates in the oil supply line and the standby oil line, and at the same time, this internal circulation oil line also has the function of heat dissipation. When the hydraulic actuator needs to work, it can enter the hydraulic actuator working state. The first directional control valve is energized and commutated to connect the oil supply line, and the second directional control valve is commutated to close the standby oil line. The high-pressure hydraulic oil circulating in the standby oil line and the oil supply line can be directly supplied to the hydraulic actuator, improving the response efficiency of the hydraulic control system, and is particularly suitable for working conditions where the hydraulic actuator needs to respond as soon as possible.

[0010] For example, when the hydraulic control system provided by the present invention is applied to a fire truck, the hydraulic control system can be in the standby state during the operation of the fire truck. After the fire truck arrives at the fire scene, it can be switched from the standby state to the hydraulic actuator working state, which can improve the response efficiency of the fire truck and can extinguish the fire as soon as possible to reduce the spread of the fire.

[0011] It can be understood that the hydraulic control system provided by the present invention can also energize and commutate the first directional control valve to connect the passage between the oil supply line and the hydraulic actuator, directly start the hydraulic actuator working state without passing through the standby state, and is suitable for working conditions where the response efficiency requirement of the hydraulic actuator is relatively low, which can reduce the opening time of the hydraulic oil pump and save more energy.

[0012] In addition, the hydraulic control system in the above technical solution provided by the present invention may further have the following additional technical features:

[0013] In the above technical solution, further, the inlet valve port of the first directional control valve is connected to the hydraulic oil pump, and the actuator valve port of the first directional control valve is connected to the hydraulic actuator; the inlet valve port of the second directional control valve is connected to the standby oil line, and the first actuator valve port of the second directional control valve is connected to the fuel tank; the hydraulic oil pump is a load-sensing pump, and the output end of the load-sensing pump is connected to the inlet valve port of the first directional control valve through the oil supply line, and the load-sensing port of the load-sensing pump is connected to the return valve port of the first directional control valve through the constant-pressure oil line; wherein, the second directional control valve is arranged on the standby oil line and the constant-pressure oil line, the load-sensing port of the load-sensing pump is connected to the second actuator valve port of the second directional control valve, and the return valve port of the second directional control valve is connected to the return valve port of the first directional control valve.

[0014] In this technical solution, the valve port connection relationship of the first reversing valve, the valve port connection relationship of the second reversing valve, the type of hydraulic oil pump and the setting of the constant pressure oil circuit are further provided. The hydraulic oil pump is a load sensitive pump. The load sensitive pump has a wider application range as a variable pump. The second reversing valve is arranged on the standby oil circuit and the constant pressure oil circuit to control the on and off of the standby oil circuit and the constant pressure oil circuit, so that the hydraulic control system further has a constant pressure working state. During the working process, after the hydraulic control system switches from the standby state to the hydraulic actuator working state, the first reversing valve is first energized and reversed, so that the oil supply circuit and the hydraulic actuator are connected, and the hydraulic oil supplied by the hydraulic oil pump is delivered to the hydraulic actuator, so that the hydraulic actuator is put into the working state as soon as possible. In this state, the return oil of the hydraulic control system can be returned to the oil tank through the return oil port of the hydraulic actuator and the standby oil circuit. When the constant pressure working state needs to be started after the hydraulic actuator enters the working state, the second reversing valve is controlled to reverse and the constant pressure oil circuit is opened. At this time, the return oil of the hydraulic control system returns to the load sensitive port of the load sensitive pump through the constant pressure oil circuit.

[0015] For example, when the hydraulic control system of the present invention is applied to a fire truck, the standby mode can be started in the fire truck form state. When the fire truck switches from the form state to the water pumping state and needs to control the extension of the outriggers and the boom, the hydraulic system can be controlled to enter the hydraulic actuator working mode. After the outriggers are firmly fixed and the boom is extended to the expected position, the hydraulic control system can enter the constant pressure operation mode, and the load-sensitive pump enters the constant pressure operation mode.

[0016] In any of the above technical solutions, further, the hydraulic control system also includes: a first damping hole, which is arranged on the constant pressure oil circuit and is located between the second reversing valve and the load sensitive port; a first one-way valve, which is located on the constant pressure oil circuit, and the oil outlet valve port of the first one-way valve is connected to the constant pressure oil circuit, and the connection point between the oil inlet valve port of the first one-way valve and the constant pressure oil circuit is located between the first damping hole and the load sensitive port, and the connection point between the oil outlet valve of the first one-way valve and the constant pressure oil circuit is located between the first damping hole and the second actuator valve port of the second reversing valve.

[0017] In this technical solution, a first damping hole and a first one-way valve are further included, so that under constant pressure operation, the hydraulic oil passes through the first damping hole and then returns to the load-sensitive port of the load-sensitive pump. The setting of the first one-way valve can avoid instantaneous changes in the oil pump displacement, which causes changes in the return oil volume and impacts the hydraulic oil pump, thereby reducing the hydraulic oil pump displacement impact and improving the service life of the hydraulic oil pump and the stability of the hydraulic control system.

[0018] In any of the above technical solutions, further, the hydraulic control system further includes: a plurality of third reversing valves; the oil supply circuit includes: a main circuit, the hydraulic oil pump is connected to the main circuit; a plurality of branch circuits, the plurality of branch circuits are connected to the main circuit; wherein, the number of hydraulic actuators is a plurality, each branch circuit is correspondingly connected to one or more hydraulic actuators and a third reversing valve, the oil return valve port of each third reversing valve is connected to the fuel tank, the oil inlet valve port of each third reversing valve is connected to the main circuit, and each actuator valve port of each third reversing valve is connected to a hydraulic actuator.

[0019] In this technical solution, the oil supply circuit further includes a main circuit and a plurality of branch circuits, the plurality of branch circuits are connected to the main circuit, and one hydraulic actuator and one third reversing valve are arranged on each branch circuit. Such an arrangement enables a hydraulic oil pump to drive a plurality of hydraulic actuators to work, improving the operation efficiency of the hydraulic control system on the one hand; on the other hand, the setting of the third reversing valve can control the connection and disconnection of each branch circuit, making the hydraulic control system more controllable and expanding the applicable range of the hydraulic control system.

[0020] In any of the above technical solutions, further, the hydraulic control system further includes: a second damping hole, arranged on the standby oil path, between the fuel tank and the second reversing valve.

[0021] In this technical solution, a second damping hole arranged on the standby oil path is further included. By setting the second damping hole, the flow rate of the hydraulic oil passing through the second reversing valve in the standby oil path can be controlled, making the hydraulic control system safer to use.

[0022] In any of the above technical solutions, further, the hydraulic control system further includes: a second one-way valve, arranged on the oil supply path, between the connection of the standby oil path and the oil supply path and the hydraulic oil pump.

[0023] In this technical solution, a second one-way valve is further included. By setting the second one-way valve, the pressure of the hydraulic oil in the oil supply path can be controlled, making the oil path pressure in the hydraulic control system controllable and making the hydraulic control system safer to use.

[0024] In any of the above technical solutions, further, the hydraulic control system further includes: a radiator, arranged on the standby oil path, between the second reversing valve and the fuel tank.

[0025] In this technical solution, a radiator is further included. By setting the radiator, in the standby state, the hydraulic oil returns to the fuel tank after passing through the radiator, which can reduce the temperature of the hydraulic oil and make the hydraulic control system safer to use.

[0026] Specifically, the oil return port of the hydraulic actuator can be connected to the radiator, so that the oil return of the hydraulic actuator returns to the fuel tank after passing through the radiator, thereby achieving the effect of cooling the hydraulic oil.

[0027] According to a second aspect of the present invention, a fire truck is provided, including: a chassis; outriggers provided on the chassis; a boom provided on the chassis; the hydraulic control system of any of the above technical solutions, wherein the hydraulic actuators of the hydraulic control system include outrigger cylinders and boom cylinders, the outrigger cylinders are connected to the outriggers and are used to drive the outriggers to extend or retract, and the boom cylinders are connected to the boom and are used to drive the boom to extend or retract.

[0028] For the fire truck provided by the present invention, since the fire truck includes the above-mentioned hydraulic control system, the fire truck has all the beneficial technical effects of the hydraulic control system.

[0029] According to a third aspect of the present invention, a method for controlling the standby state of a fire truck during operation is provided for the above-mentioned fire truck. The method for controlling the standby state of the fire truck during operation includes: receiving a standby instruction of the fire truck and starting the hydraulic oil pump; controlling the first reversing valve and the second reversing valve to change the direction, disconnecting the passage between the oil supply line and the hydraulic actuator, and conducting the standby oil line so that the hydraulic oil flows through the standby oil line and returns to the fuel tank; receiving an operation instruction of the fire truck, controlling the first reversing valve to change the direction, and then controlling the second reversing valve to change the direction, conducting the oil inlet valve port and the execution valve port of the first reversing valve, and disconnecting the standby oil line so that the hydraulic oil is supplied to the hydraulic actuator through the oil supply line.

[0030] For the method for controlling the standby state of the fire truck during operation provided by the present invention, when receiving the standby instruction of the fire truck, in response to the standby instruction of the fire truck, the fire truck enters the standby state and starts the hydraulic oil pump; controlling the first reversing valve and the second reversing valve to change the direction, disconnecting the passage between the oil supply line and the hydraulic actuator, and conducting the standby oil line, so that the hydraulic oil flows through the second reversing valve and the standby oil line and returns to the fuel tank, which can improve the response efficiency of the fire truck; when receiving the operation instruction, the fire truck enters the working state of the hydraulic actuator, first controls the first reversing valve to change the direction, conducts the oil inlet valve port and the execution valve port of the first reversing valve, and then the second reversing valve changes the direction to disconnect the standby oil line, so that the hydraulic oil is supplied to the hydraulic actuator through the oil supply line, enabling the boom and outriggers of the fire truck to act as expected.

[0031] In addition, the method for controlling the standby state of the fire truck during operation in the above technical solution provided by the present invention may further have the following additional technical features:

[0032] In the above technical solution, further, the steps of controlling the reversing of the first reversing valve and the second reversing valve to disconnect the passage between the oil supply circuit and the hydraulic actuator, and opening the standby oil circuit so that the hydraulic oil flows through the standby oil circuit and returns to the oil tank, specifically include: controlling the first reversing valve and the second reversing valve to cut off power to disconnect the passage between the oil supply circuit and the hydraulic actuator, and opening the standby oil circuit so that the hydraulic oil flows through the standby oil circuit and returns to the oil tank.

[0033] In this technical solution, specific steps are further provided for the hydraulic oil pump to return to the oil tank through the standby oil circuit. By de-energizing the first reversing valve and the second reversing valve, the first reversing valve disconnects the oil supply circuit, and the oil inlet valve port of the second reversing valve is connected to the first execution valve port of the second reversing valve, so that the hydraulic oil can return to the oil tank through the standby oil circuit.

[0034] In the above technical solution, further, when the hydraulic oil pump is a load-sensitive pump, the output end of the load-sensitive pump is connected to the oil inlet valve port of the first reversing valve through the oil supply circuit, and the load-sensitive port of the load-sensitive pump is connected to the oil return valve port of the first reversing valve through the constant pressure oil circuit; the second reversing valve is arranged in the standby oil circuit and the constant pressure oil circuit, the load-sensitive port of the load-sensitive pump is connected to the second execution valve port of the second reversing valve, and the oil return valve port of the second reversing valve is connected to the oil return valve port of the first reversing valve, the operation instruction of the fire truck is received, and the reversing of the first reversing valve is controlled, and Then, the second reversing valve is controlled to be reversed, the oil inlet valve port and the execution valve port of the first reversing valve are connected, and the standby oil circuit is disconnected so that the hydraulic oil is supplied to the hydraulic actuator through the oil supply circuit and then returns to the oil tank. The steps specifically include: receiving the operation instruction of the fire truck, controlling the reversing of the first reversing valve, so that the oil inlet valve port of the first reversing valve is connected to the execution valve port; controlling the reversing of the second reversing valve, so that the oil return valve port of the second reversing valve is connected to the second execution valve port of the second reversing valve, and the hydraulic oil is supplied to the hydraulic actuator through the oil supply circuit and then returns to the load sensitive port via the constant pressure oil circuit.

[0035] In this technical solution, the fire truck is further equipped with a constant pressure working mode. During operation, after the hydraulic control system switches from the standby mode to the hydraulic actuator working mode, the first reversing valve is energized and reversed first, so that the oil supply circuit and the hydraulic actuator are connected, and the hydraulic oil supplied by the hydraulic oil pump is delivered to the hydraulic actuator, so that the hydraulic actuator can be put into the working state as soon as possible. In this state, the return oil of the hydraulic control system can be returned to the oil tank through the return oil port of the hydraulic actuator and the standby oil circuit. When the constant pressure working mode needs to be started after the hydraulic actuator enters the working state, the second reversing valve is controlled to reverse, and the return oil valve port of the second reversing valve is connected to the second actuator valve port to open the constant pressure oil circuit. At this time, the return oil of the hydraulic control system is returned to the load sensitive port of the load sensitive pump through the constant pressure oil circuit.

[0036] In any of the above technical solutions, further, the hydraulic control system further includes: a plurality of third reversing valves; the oil supply circuit includes: a main circuit and a plurality of branch circuits, the hydraulic oil pump is connected to the main circuit; the plurality of branch circuits are connected to the main circuit; each branch circuit is correspondingly connected to one or several hydraulic actuators and a third reversing valve, the oil return valve port of each third reversing valve is connected to the fuel tank, the oil inlet valve port of each third reversing valve is connected to the main circuit, and the actuator valve port of each third reversing valve is connected to a hydraulic actuator. The fire truck operation standby control method further includes: receiving a stop operation instruction, controlling the second reversing valve to reverse, so that the oil inlet valve port of the second reversing valve is conducted to the first actuator valve port of the second reversing valve; when the hydraulic oil supplied by the hydraulic oil pump returns to the fuel tank through the oil return valve port of the third reversing valve and the first actuator valve port of the second reversing valve, controlling the first reversing valve to cut off the power supply.

[0037] In this technical solution, a control method for the hydraulic control system when the fire truck stops operating is further provided. The oil inlet valve port of the second reversing valve is conducted to the first actuator valve port of the second reversing valve, so that the hydraulic oil in the hydraulic control system returns to the fuel tank through the oil return valve port of the third reversing valve and the first actuator valve port of the second reversing valve, which can avoid the hydraulic oil pump from being blocked by pressure, and improve the safety, stability and service life of the fire truck.

[0038] The additional aspects and advantages of the present invention will become obvious in the following description part, or be understood through the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] The above and / or additional aspects and advantages of the present invention will become obvious and easy to understand from the description of the embodiments in conjunction with the following drawings, wherein:

[0040] Figure 1 Shows a schematic structural diagram of a hydraulic control system provided according to an embodiment of the present invention;

[0041] Figure 2 Shows a schematic structural diagram of a fire truck provided according to an embodiment of the present invention;

[0042] Figure 3 Is a first step flow chart of a fire truck operation standby control method according to some embodiments of the present invention;

[0043] Figure 4 Is a second step flow chart of a fire truck operation standby control method according to some embodiments of the present invention;

[0044] Figure 5 Is a third step flow chart of a fire truck operation standby control method according to some embodiments of the present invention;

[0045] Figure 6This is the flowchart of the fourth step of the operation standby control method for a fire truck according to some embodiments of the present invention.

[0046] Among them, Figure 1 and Figure 2 the corresponding relationship between the reference numerals and the component names in the figure is as follows:

[0047] 2 hydraulic actuators, 4 hydraulic oil pumps, 6 first reversing valves, 8 second reversing valves, 10 first damping holes, 12 second damping holes, 14 second check valves, 16 radiators, 18 outriggers, 20 booms, 22 first check valves, 24 center swivel joints, 26 fuel tanks, 602 inlet valve ports of the first reversing valve, 604 actuator valve ports of the first reversing valve, 606 return valve ports of the first reversing valve, 802 inlet valve ports of the second reversing valve, 804 first actuator valve ports of the second reversing valve, 806 second actuator valve ports of the second reversing valve, 808 return valve ports of the second reversing valve; 402 load sensing ports. Detailed implementation manners

[0048] In order to more clearly understand the above objects, features and advantages of the present invention, the present invention will be further described in detail below with reference to the drawings and specific implementation manners. It should be noted that, without conflict, the embodiments of the present application and the features in the embodiments can be combined with each other.

[0049] In the following description, many specific details are set forth in order to fully understand the present invention. However, the present invention can also be implemented in other ways different from those described herein. Therefore, the protection scope of the present invention is not limited by the specific embodiments disclosed below.

[0050] Next, refer to Figures 1 to 6 to describe a hydraulic control system, a fire truck and a fire truck operation standby control method according to some embodiments of the present invention.

[0051] Embodiment 1

[0052] As Figure 1 shown, an embodiment of the present invention provides a hydraulic control system, including: a hydraulic actuator 2, a hydraulic oil pump 4, a first reversing valve 6, a standby oil circuit and a second reversing valve 8.

[0053] Among them, the hydraulic oil pump 4 is connected to the hydraulic actuator 2 through an oil supply circuit; the first reversing valve 6 is arranged on the oil supply circuit, between the hydraulic oil pump 4 and the hydraulic actuator 2; one end of the standby oil circuit is communicated with the oil supply circuit, and the other end is communicated with the fuel tank 26. The connection part of the standby oil circuit and the oil supply circuit is located between the first reversing valve 6 and the hydraulic oil pump 4; the second reversing valve 8 is arranged on the standby oil circuit.

[0054] The hydraulic control system provided by the present invention can have a standby state and a working state of the hydraulic actuator 2 during operation. In the standby state, the first reversing valve 6 is controlled to be de-energized or reversed to disconnect the passage between the oil supply line and the hydraulic actuator 2, the second reversing valve 8 is controlled to be energized and reversed to connect the standby oil line, and the hydraulic oil pump 4 is controlled to start, supplying the hydraulic oil in the fuel tank 26 into the standby oil line. The hydraulic oil in the low-pressure and small-flow state circulates in the standby oil line. When the hydraulic actuator 2 needs to work, it can enter the working state of the hydraulic actuator 2. The first reversing valve 6 is energized and reversed to connect the oil supply line, and the second reversing valve 8 is reversed to close the standby oil line. The hydraulic control system is switched to the constant pressure mode, and the low-pressure and small-flow hydraulic oil circulating in the standby oil line and the oil supply line can be converted into high-pressure hydraulic oil and directly supplied to the hydraulic actuator 2, improving the response efficiency of the hydraulic control system, and is particularly suitable for working conditions where the hydraulic actuator 2 needs to respond as soon as possible.

[0055] For example, when the hydraulic control system provided by the present invention is applied to a fire truck, the hydraulic control system can be in the standby state during the operation of the fire truck. After the fire truck arrives at the fire scene, it can be switched from the standby state to the working state of the hydraulic actuator 2, which can improve the response efficiency of the fire truck and can extinguish the fire as soon as possible to reduce the spread of the fire.

[0056] It can be understood that the hydraulic control system provided by the present invention can also connect the passage between the oil supply line and the hydraulic actuator 2 by energizing and reversing the first reversing valve 6, and directly start the working state of the hydraulic actuator 2 without passing through the standby state, which is suitable for working conditions with relatively low requirements for the response efficiency of the hydraulic actuator 2, can reduce the starting time of the hydraulic oil pump 4, and is more energy-saving.

[0057] Embodiment 2

[0058] As Figure 1 shown, an embodiment of the present invention provides a hydraulic control system, including: a hydraulic actuator 2, a hydraulic oil pump 4, a first reversing valve 6, a standby oil line, and a second reversing valve 8.

[0059] Among them, the hydraulic oil pump 4 is connected to the hydraulic actuator 2 through an oil supply line; the first reversing valve 6 is arranged on the oil supply line, the hydraulic oil pump 4 is connected to the inlet valve port 602 of the first reversing valve, and the hydraulic actuator 2 is connected to the actuator valve port 604 of the first reversing valve; one end of the standby oil line is connected to the oil supply line, and the other end is connected to the fuel tank 26. The connection point between the standby oil line and the oil supply line is located between the first reversing valve 6 and the hydraulic oil pump 4; the second reversing valve 8 is arranged on the standby oil line, the standby oil line is connected to the inlet valve port 802 of the second reversing valve, and the first actuator valve port 804 of the second reversing valve is connected to the fuel tank 26.

[0060] Furthermore, the hydraulic oil pump 4 is a load-sensitive pump, and the output end of the load-sensitive pump is connected to the oil inlet valve port 602 of the first reversing valve through the oil supply circuit, and the load-sensitive port 402 of the load-sensitive pump is connected to the oil return valve port 606 of the first reversing valve through the constant pressure oil circuit; wherein, the second reversing valve 8 is arranged in the standby oil circuit and the constant pressure oil circuit, the load-sensitive port 402 of the load-sensitive pump is connected to the second execution valve port 806 of the second reversing valve, and the return oil valve port 808 of the second reversing valve is connected to the return oil valve port 606 of the first reversing valve.

[0061] In this embodiment, the type of hydraulic oil pump 4 and the setting of constant pressure oil circuit are further provided. The hydraulic oil pump 4 is a load sensitive pump. As a variable pump, the load sensitive pump has a wider application range. The second reversing valve 8 is arranged on the standby oil circuit and the constant pressure oil circuit to control the on and off of the standby oil circuit and the constant pressure oil circuit, so that the hydraulic control system further has a constant pressure working state. During the working process, after the hydraulic control system switches from the standby state to the working state of the hydraulic actuator 2, the first reversing valve 6 is first energized and reversed, so that the oil supply circuit and the hydraulic actuator 2 are connected, and the hydraulic oil supplied by the hydraulic oil pump 4 is delivered to the hydraulic actuator 2, so that the hydraulic actuator 2 is put into the working state as soon as possible. In this state, the return oil of the hydraulic control system can be returned to the oil tank 26 through the return oil port of the hydraulic actuator 2 and the standby oil circuit. When the constant pressure working state needs to be started after the hydraulic actuator 2 enters the working state, the second reversing valve 8 is controlled to reverse and the constant pressure oil circuit is opened. At this time, the return oil of the hydraulic control system returns to the load sensitive port 402 of the load sensitive pump through the constant pressure oil circuit.

[0062] For example, when the hydraulic control system of the present invention is applied to a fire truck, the standby mode can be started in the fire truck form state. When the fire truck switches from the driving state to the water pumping state and needs to control the extension of the outriggers 18 and the boom 20, the hydraulic system can be controlled to enter the constant pressure operation mode to extend the outriggers 18 and the boom 20 to the expected position as soon as possible. When the outriggers 18 and the boom 20 are not moving, the load-sensitive pump enters a low-flow standby mode.

[0063] Embodiment 3

[0064] like Figure 1 As shown, an embodiment of the present invention provides a hydraulic control system, including: a hydraulic actuator 2, a hydraulic oil pump 4, a first reversing valve 6, a standby oil circuit and a second reversing valve 8.

[0065] Among them, the hydraulic oil pump 4 is connected to the hydraulic actuator 2 through an oil supply line; the first reversing valve 6 is arranged on the oil supply line, the hydraulic oil pump 4 communicates with the inlet valve port 602 of the first reversing valve, and the hydraulic actuator 2 communicates with the actuator valve port 604 of the first reversing valve; one end of the standby oil line communicates with the oil supply line, and the other end communicates with the fuel tank 26. The connection between the standby oil line and the oil supply line is located between the first reversing valve 6 and the hydraulic oil pump 4; the second reversing valve 8 is arranged on the standby oil line, the standby oil line communicates with the inlet valve port 802 of the second reversing valve, and the first actuator valve port 804 of the second reversing valve communicates with the fuel tank 26.

[0066] Further, the hydraulic oil pump 4 is a load-sensitive pump. The output end of the load-sensitive pump communicates with the inlet valve port 602 of the first reversing valve through an oil supply line, and the load-sensitive port 402 of the load-sensitive pump communicates with the return valve port 606 of the first reversing valve through a constant-pressure oil line; among them, the second reversing valve 8 is arranged on the standby oil line and the constant-pressure oil line. The load-sensitive port 402 of the load-sensitive pump communicates with the second actuator valve port 806 of the second reversing valve, and the return valve port 808 of the second reversing valve communicates with the return valve port 606 of the first reversing valve.

[0067] Further, the hydraulic control system further includes: a first damping orifice 10, arranged on the constant-pressure oil line, between the second reversing valve 8 and the load-sensitive port 402; a first check valve 22, the first check valve 22 is located on the constant-pressure oil line. The oil outlet valve port of the first check valve 22 communicates with the constant-pressure oil line. The connection between the oil inlet valve port of the first check valve 22 and the constant-pressure oil line is located between the first damping orifice 10 and the load-sensitive port 402. The connection between the oil outlet valve of the first check valve 22 and the constant-pressure oil line is located between the first damping orifice 10 and the second actuator valve port 806 of the second reversing valve.

[0068] In this embodiment, the first damping orifice 10 and the first check valve 22 are further included, so that under the constant-pressure operation mode, the hydraulic oil returns to the load-sensitive port 402 of the load-sensitive pump after passing through the first damping orifice 10. The setting of the first check valve 22 can avoid the instantaneous change of the pump displacement, resulting in the instantaneous flow rate of the hydraulic system impacting the hydraulic oil pump 4, reducing the displacement impact of the hydraulic oil pump 4, and improving the service life of the hydraulic oil pump 4 and the stability of the hydraulic control system.

[0069] Embodiment 4

[0070] As Figure 1 shown, an embodiment of the present invention provides a hydraulic control system, including: a hydraulic actuator 2, a hydraulic oil pump 4, a first reversing valve 6, a standby oil line, and a second reversing valve 8.

[0071] Among them, the hydraulic oil pump 4 is connected to the hydraulic actuator 2 through an oil supply line; the first reversing valve 6 is arranged on the oil supply line, the hydraulic oil pump 4 is communicated with the inlet valve port 602 of the first reversing valve, and the hydraulic actuator 2 is communicated with the actuator valve port 604 of the first reversing valve; one end of the standby oil line is communicated with the oil supply line, and the other end is communicated with the fuel tank 26. The connection point between the standby oil line and the oil supply line is located between the first reversing valve 6 and the hydraulic oil pump 4; the second reversing valve 8 is arranged on the standby oil line, the standby oil line is communicated with the inlet valve port 802 of the second reversing valve, and the first actuator valve port 804 of the second reversing valve is communicated with the fuel tank 26.

[0072] Further, the hydraulic control system further includes: a plurality of third reversing valves; the oil supply line includes: a main line, and the hydraulic oil pump 4 is communicated with the main line; a plurality of branch lines, and the plurality of branch lines are communicated with the main line; wherein, the number of hydraulic actuators 2 is multiple, each branch line is correspondingly connected to one or more hydraulic actuators 2 and a third reversing valve, the oil return valve port of each third reversing valve is communicated with the fuel tank 26, the inlet valve port of each third reversing valve is communicated with the main line, and each actuator valve port of each third reversing valve is communicated with a hydraulic actuator 2.

[0073] In this embodiment, the oil supply line further includes a main line and a plurality of branch lines, the plurality of branch lines are communicated with the main line, and one hydraulic actuator 2 and one third reversing valve are arranged on each branch line. Such an arrangement makes it possible for one hydraulic oil pump 4 to drive multiple hydraulic actuators 2 to work, improving the operation efficiency of the hydraulic control system; on the other hand, the controllability of the hydraulic control system is stronger through the setting of the third reversing valve, and the applicable range of the hydraulic control system is improved.

[0074] Embodiment Five

[0075] As Figure 1 shown, on the basis of any one of Embodiments One to Four, further, the hydraulic control system further includes: a second damping hole 12, arranged on the standby oil line, between the fuel tank 26 and the second reversing valve 8.

[0076] In this embodiment, a second damping hole 12 arranged on the standby oil line is further included. By setting the second damping hole 12, the flow rate of the hydraulic oil passing through the second reversing valve 8 in the standby oil line can be controlled. The second damping hole 12 can control the displacement of the hydraulic oil pump 4 in the standby state, and further control the flow rate in the standby oil line. The small-flow hydraulic oil enters the radiator for oil return and heat dissipation, making the hydraulic control system safer to use.

[0077] Embodiment Six

[0078] As Figure 1As shown, based on any one of Embodiments 1 to 4, further, the hydraulic control system further includes: a second one-way valve 14, which is arranged on the oil supply path and is located between the connection of the standby oil path and the oil supply path and the hydraulic oil pump 4.

[0079] In this embodiment, the second one-way valve 14 is further included. By setting the second one-way valve 14, the pressure of the hydraulic oil in the oil supply path can be controlled, so that the oil path pressure in the hydraulic control system is controllable, avoiding the hydraulic system from impacting the hydraulic oil pump 4 and making the hydraulic control system safer to use.

[0080] Embodiment 7

[0081] As Figure 1 shown, based on any one of Embodiments 1 to 4, further, the hydraulic control system further includes: a radiator 16, which is arranged on the standby oil path and is located between the second reversing valve 8 and the fuel tank 26.

[0082] In this embodiment, the radiator 16 is further included. By setting the radiator 16, in the standby state, the hydraulic oil returns to the fuel tank 26 after passing through the radiator 16, which can reduce the temperature of the hydraulic oil and make the hydraulic control system safer to use.

[0083] Specifically, the oil return port of the hydraulic actuator 2 can be connected to the radiator 16, so that the oil return of the hydraulic actuator 2 passes through the radiator 16 and then returns to the fuel tank 26 to achieve the effect of cooling the hydraulic oil.

[0084] Embodiment 8

[0085] As Figure 2 shown, an embodiment of the present invention provides a fire truck, including: outriggers 18, which are arranged on the chassis; a boom 20, which is arranged on the chassis; the hydraulic control system of any one of the above embodiments, and the hydraulic actuator 2 of the hydraulic control system includes an outrigger cylinder and a boom cylinder. The outrigger cylinder is connected to the outrigger 18 and is used to drive the outrigger 18 to extend or retract, and the boom cylinder is connected to the boom 20 and is used to drive the boom 20 to extend or retract.

[0086] For the fire truck provided in this embodiment, since the fire truck includes the above-mentioned hydraulic control system, the fire truck has all the beneficial technical effects of the hydraulic control system.

[0087] Specifically, the hydraulic control system further includes: a plurality of third reversing valves; the oil supply circuit includes: a main circuit, and the hydraulic oil pump 4 is connected to the main circuit; a plurality of branch circuits, and the plurality of branch circuits are connected to the main circuit; wherein, the number of hydraulic actuators 2 is multiple, each branch circuit is correspondingly connected to a hydraulic actuator 2 and a third reversing valve, the oil return valve port of each third reversing valve is connected to the fuel tank 26, the oil inlet valve port of each third reversing valve is connected to the main circuit, and the actuator valve port of each third reversing valve is connected to a hydraulic actuator 2. The plurality of branch circuits are divided into two groups, one group of branch circuits is connected to the boom 20, and the other group is connected to the outriggers 18, and a central swivel joint 24 is provided on the branch circuit connected to the boom.

[0088] Embodiment Nine

[0089] As Figure 3 shown, an embodiment of the present invention provides a fire truck operation standby control method for the above-mentioned fire truck. The fire truck operation standby control method includes:

[0090] Step 302: Receive the standby instruction of the fire truck and start the hydraulic oil pump;

[0091] Step 304: Control the first reversing valve and the second reversing valve to reverse, disconnect the passage between the oil supply circuit and the hydraulic actuator, and conduct the standby oil circuit so that the hydraulic oil flows through the standby oil circuit and returns to the fuel tank;

[0092] Step 306: Receive the operation instruction of the fire truck, control the first reversing valve to reverse, and then control the second reversing valve to reverse, conduct the oil inlet valve port and the actuator valve port of the first reversing valve, and disconnect the standby oil circuit so that the hydraulic oil is supplied to the hydraulic actuator through the oil supply circuit.

[0093] For the fire truck operation standby control method provided by the present invention, when receiving the standby instruction of the fire truck, in response to the standby instruction of the fire truck, the fire truck enters the standby state and starts the hydraulic oil pump; controlling the first reversing valve and the second reversing valve to be powered off so that the hydraulic oil flows through the standby oil circuit and returns to the fuel tank can improve the response efficiency of the fire truck, and the hydraulic oil can dissipate heat in the standby state; at this time, the hydraulic oil in the hydraulic control system returns to the fuel tank for heat dissipation through the damping hole. The damping hole can control the displacement of the hydraulic oil pump 4, and further control the flow rate of the standby oil circuit, avoiding heat generation caused by low-pressure and large-flow oil return. When receiving the operation instruction, the fire truck enters the working state of the hydraulic actuator, controls the first reversing valve to reverse, and conducts the oil inlet valve port and the actuator valve port of the first reversing valve, so that the hydraulic oil is supplied to the hydraulic actuator through the oil supply circuit or returns to the fuel tank after passing through the third reversing valve connected to the hydraulic actuator, enabling the boom and outriggers of the fire truck to enter the working state as expected.

[0094] Embodiment Ten

[0095] As Figure 4As shown in the figure, an embodiment of the present invention provides a fire truck operation standby control method for the above-mentioned fire truck. The fire truck operation standby control method includes:

[0096] Step 502: Receive the standby instruction of the fire truck and turn on the hydraulic oil pump;

[0097] Step 504: Control the first directional valve and the second directional valve to be de-energized to disconnect the passage between the oil supply line and the hydraulic actuator, and conduct the standby oil line so that the hydraulic oil flows through the standby oil line and returns to the fuel tank;

[0098] Step 506: Receive the operation instruction of the fire truck, control the first directional valve to change direction, and then control the second directional valve to change direction, conduct the inlet valve port and the actuator valve port of the first directional valve, and disconnect the standby oil line so that the hydraulic oil is supplied to the hydraulic actuator through the oil supply line.

[0099] In this technical solution, the specific steps for the hydraulic oil pump to flow through the standby oil line and return to the fuel tank are further provided. By de-energizing the first directional valve and the second directional valve, the first directional valve disconnects the passage of the oil supply line, and the inlet valve port of the second directional valve is conducted to the first actuator valve port of the second directional valve, so that the hydraulic oil can return to the fuel tank via the standby oil line.

[0100] Embodiment XI

[0101] As Figure 5 shown in the figure, when the hydraulic oil pump is a load-sensing pump, the output end of the load-sensing pump is connected to the inlet valve port of the first directional valve through the oil supply line, and the load-sensing port of the load-sensing pump is connected to the return valve port of the first directional valve through the constant-pressure oil line; the second directional valve is arranged on the standby oil line and the constant-pressure oil line, the load-sensing port of the load-sensing pump is connected to the second actuator valve port of the second directional valve, and the return valve port of the second directional valve is connected to the return valve port of the first directional valve, the fire truck operation standby control method includes:

[0102] Step 702: Receive the standby instruction of the fire truck and turn on the hydraulic oil pump;

[0103] Step 704: Control the first directional valve and the second directional valve to be de-energized to disconnect the passage between the oil supply line and the hydraulic actuator, and conduct the standby oil line so that the hydraulic oil flows through the standby oil line and returns to the fuel tank;

[0104] Step 706: Receive the operation instruction of the fire truck, control the first directional valve to change direction so that the inlet valve port of the first directional valve is conducted to the actuator valve port;

[0105] Step 708: Control the second directional valve to change direction so that the return valve port of the second directional valve is conducted to the second actuator valve port of the second directional valve, and the hydraulic oil is supplied to the hydraulic actuator through the oil supply line and then returns to the load-sensing port via the constant-pressure oil line.

[0106] In this technical solution, the fire truck is further equipped with a constant pressure working mode. During operation, after the hydraulic control system switches from the standby mode to the hydraulic actuator working mode, the first reversing valve is electrically reversed first, so that the oil supply circuit and the hydraulic actuator are connected, and the hydraulic oil supplied by the hydraulic oil pump is delivered to the hydraulic actuator, so that the hydraulic actuator can be put into the working state as soon as possible. In this state, the return oil of the hydraulic control system can return to the oil tank through the return oil port of the hydraulic actuator and the standby oil circuit. When the constant pressure working mode needs to be started after the hydraulic actuator enters the working state, the second reversing valve is controlled and electrically reversed, and the return valve port of the second reversing valve is connected to the second actuator valve port, opening the constant pressure oil circuit. At this time, the hydraulic control The return oil of the system returns to the load-sensitive port of the load-sensitive pump through the constant-pressure oil circuit. The first reversing valve is energized first, and then the second reversing valve is energized. The first reversing valve is energized first, and the low-pressure hydraulic oil enters the outrigger or arm multi-way valve on standby, and then the second reversing valve is energized. At this time, the low-pressure hydraulic oil in the standby oil circuit is immediately converted into high-pressure hydraulic oil and supplied to the actuator for action, avoiding the need for the load-sensitive pump to feedback the control signal from the hydraulic actuator to the oil pump, thereby improving the response speed of the hydraulic actuator. Furthermore, the damping hole of the hydraulic control system and the first one-way valve can prevent the hydraulic oil pump from being impacted. At this time, the hydraulic oil pump is in constant pressure mode. Furthermore, the time difference between the second reversing valve being energized and the first reversing valve being energized is 1s to 5s.

[0107] Embodiment 12

[0108] like Figure 6 As shown, an embodiment of the present invention provides a fire truck operation standby control method, wherein the hydraulic control system further includes: a plurality of third reversing valves; the oil supply circuit includes: a main circuit and a plurality of branches, the hydraulic oil pump is connected to the main circuit; the plurality of branches are connected to the main circuit; each branch is correspondingly connected to a hydraulic actuator and a third reversing valve, the oil return valve port of each third reversing valve is connected to the oil tank, the oil inlet valve port of each third reversing valve is connected to the main circuit, and the execution valve port of each third reversing valve is connected to a hydraulic actuator. In this case, the fire truck operation standby control method includes:

[0109] Step 902: receiving a standby command from the fire truck and starting the hydraulic oil pump;

[0110] Step 904: Control the first reversing valve and the second reversing valve to switch directions, disconnect the passage between the oil supply circuit and the hydraulic actuator, and open the standby oil circuit so that the hydraulic oil flows through the standby oil circuit and returns to the oil tank;

[0111] Step 906: receiving the operation instruction of the fire truck, controlling the first reversing valve to change direction, and then controlling the second reversing valve to change direction, connecting the oil inlet valve port and the execution valve port of the first reversing valve, disconnecting the standby oil circuit so that the hydraulic oil is supplied to the hydraulic actuator through the oil supply circuit;

[0112] Step 908: Receive a stop operation instruction, control the second reversing valve to reverse, so that the oil inlet valve port of the second reversing valve communicates with the first actuator valve port of the second reversing valve;

[0113] Step 910: When the hydraulic oil supplied by the hydraulic oil pump returns to the fuel tank through the oil return valve port of the third reversing valve and the first actuator valve port of the second reversing valve, control the first reversing valve to cut off the power.

[0114] In this technical solution, a control method for the hydraulic control system when the fire truck stops operating is further provided. The oil inlet valve port of the second reversing valve communicates with the first actuator valve port of the second reversing valve, so that the hydraulic oil in the hydraulic control system returns to the fuel tank through the oil return valve port of the third reversing valve and the first actuator valve port of the second reversing valve, which can avoid the hydraulic oil pump from being blocked by pressure, and improve the safety, stability and service life of the fire truck. Specific Embodiment

[0116] As Figure 1 shown, this embodiment provides a hydraulic control system, including: a hydraulic actuator 2; a hydraulic oil pump 4, the hydraulic oil pump 4 is connected to the hydraulic actuator 2 through an oil supply line; a first reversing valve 6, arranged on the oil supply line, the hydraulic oil pump 4 communicates with the oil inlet valve port 602 of the first reversing valve, and the hydraulic actuator 2 communicates with the actuator valve port 604 of the first reversing valve; a standby oil path, one end of the standby oil path communicates with the oil supply line, and the other end communicates with the fuel tank 26, and the connection point between the standby oil path and the oil supply line is located between the first reversing valve 6 and the hydraulic oil pump 4; a second reversing valve 8, arranged on the standby oil path, the standby oil path communicates with the oil inlet valve port 802 of the second reversing valve, and the first actuator valve port 804 of the second reversing valve communicates with the fuel tank 26.

[0117] Further, the hydraulic oil pump 4 is a load-sensing pump, the output end of the load-sensing pump communicates with the oil inlet valve port 602 of the first reversing valve through an oil supply line, and the load-sensing port 402 of the load-sensing pump communicates with the oil return valve port 606 of the first reversing valve through a constant-pressure oil line; wherein, the second reversing valve 8 is arranged on the standby oil path and the constant-pressure oil line, the load-sensing port 402 of the load-sensing pump communicates with the second actuator valve port 806 of the second reversing valve, and the oil return valve port 808 of the second reversing valve communicates with the oil return valve port 606 of the first reversing valve; when receiving a constant-pressure operation instruction, the second reversing valve 8 reverses, so that the oil return valve port 808 of the second reversing valve communicates with the second actuator valve port.

[0118] Further, the hydraulic control system further includes: a first damping hole 10, arranged on the constant-pressure oil line, between the second reversing valve 8 and the load-sensing port 402.

[0119] Further, the hydraulic control system further includes: a plurality of third reversing valves; the oil supply circuit includes: a main circuit, the hydraulic oil pump 4 is connected to the main circuit; a plurality of branch circuits, the plurality of branch circuits are connected to the main circuit; wherein, the number of hydraulic actuators 2 is a plurality, each branch circuit is correspondingly connected to a hydraulic actuator 2 and a third reversing valve, the oil return valve port of each third reversing valve is connected to the oil tank 26, the oil inlet valve port of each third reversing valve is connected to the main circuit, and the actuator valve port of each third reversing valve is connected to a hydraulic actuator 2.

[0120] Further, the hydraulic control system further includes: a second damping hole 12, which is arranged on the standby oil path and is located between the oil tank 26 and the second reversing valve 8.

[0121] Further, the hydraulic control system further includes: a second one-way valve 14, which is arranged on the oil supply path and is located between the connection of the standby oil path and the oil supply path and the hydraulic oil pump 4.

[0122] Further, the hydraulic control system further includes: a radiator 16, which is arranged on the standby oil path and is located between the second reversing valve 8 and the oil tank 26.

[0123] Specifically, as Figure 1 shown, when the first reversing valve 6 is energized, the first reversing valve 6 is in the left position, the oil inlet valve port 602 of the first reversing valve is connected to the actuator valve port 604 of the first reversing valve, and when the first reversing valve 6 is de-energized, the first reversing valve 6 disconnects the passage between the oil supply circuit and the hydraulic actuator 2; when the second reversing valve 8 is de-energized, the oil inlet valve port of the second reversing valve is connected to the first actuator valve port 804 of the second reversing valve, and when the second reversing valve 8 is energized, the oil return valve port 808 of the second reversing valve is connected to the second actuator valve port.

[0124] When the hydraulic control system provided in this embodiment is on standby, the outlet of the load sensing pump returns to the oil tank 26 through the second reversing valve 8 and the second damping hole 12 and then through the radiator 16.

[0125] In the hydraulic control system provided in this embodiment, when the hydraulic actuator 2 needs to be driven and the load needs to act, the first reversing valve 6 is first energized, and the second reversing valve 8 is energized with a delay.

[0126] In the hydraulic control system provided in this embodiment, when the system stops, the second reversing valve 8 is first de-energized, and the first reversing valve 6 is first energized and then de-energized with a delay.

[0127] In the hydraulic control system provided in this embodiment, the second valve port of the second reversing valve 8 is connected in series with the second damping hole 12 and then connected back to the load sensing port (LS port) of the load sensing pump.

[0128] For the hydraulic control system provided in this embodiment, when the system is on standby, the flow rate through the first valve port of the second control valve is only related to the cross-sectional area of the second damping orifice 12, and the standby pressure is the spring force of the second check valve 14.

[0129] The hydraulic control system provided in this embodiment can be applied to a fire truck. When the boom 20 or outrigger 18 system of the fire truck is working, the first reversing valve 6 is first energized, and the flow rate of the hydraulic oil pump 4 returns from the third reversing valve of the boom 20 or the third reversing valve of the outrigger 18 of the first reversing valve 6 to the oil return tank 26, and at the same time can pass through the first valve port of the second reversing valve 8 and the first damping orifice 10 to the oil return tank 26; then the second reversing valve 8 is energized with a time delay, and the oil pressure passes through the second valve port of the second reversing valve 8, passes through the second damping orifice 12 to the LS port of the hydraulic oil pump 4, and the hydraulic oil pump 4 switches to the constant pressure variable pump mode; due to the existence of the second damping orifice 12, the instantaneous change of the displacement of the hydraulic oil pump 4 is avoided, and the displacement impact of the hydraulic oil pump 4 is reduced. Specifically, the third reversing valve can be a three-way flow valve.

[0130] When the hydraulic control system of the fire truck stops working, the second reversing valve 8 is first de-energized, and the flow rate of the hydraulic oil pump 4 returns from the first reversing valve 6 through the third reversing valve of the boom 20 or the outrigger 18 to the oil return tank 26, and at the same time can pass through the first valve port of the second reversing valve 8 and the first damping orifice 10 to the oil return tank 26; the first reversing valve 6 is de-energized with a time delay to avoid overpressure of the hydraulic oil pump 4.

[0131] The hydraulic control system provided in this embodiment has the following beneficial effects:

[0132] 1. By using a common load-sensing pump, the control mode of two-point pump can be realized.

[0133] 2. During low-speed and high-speed standby, medium and small flow rates are output, and the oil can be returned to the radiator 16 for heat dissipation, avoiding high hydraulic oil temperature when the fire truck continuously sprays water for a long time and the hydraulic oil pump is in high-speed standby.

[0134] 3. Performance: Improve the control strategy, combine hardware and software, the standby flow rate is always ready, improve the response speed of the system, and reduce the pressure impact during the commutation of the reversing valve.

[0135] 4. There is no impact on the displacement of the hydraulic oil pump 4 during start and stop.

[0136] In the present invention, terms such as "installation", "connection", "linkage", "fixation" should be understood in a broad sense. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; "linkage" can be a direct linkage or an indirect linkage through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0137] In the description of this specification, the descriptions of terms such as "one embodiment", "some embodiments", "specific embodiments", etc. mean that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or instance. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0138] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and changes. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A hydraulic control system, characterized in that, Comprising: A hydraulic actuator; A hydraulic oil pump, which is connected to the hydraulic actuator through an oil supply line; A first reversing valve, which is arranged on the oil supply line and located between the hydraulic oil pump and the hydraulic actuator; An oil path to be idled, one end of the oil path to be idled is communicated with the oil supply line, and the other end is communicated with a fuel tank. The connection part of the oil path to be idled and the oil supply line is located between the first reversing valve and the hydraulic oil pump; A second reversing valve, which is arranged on the oil path to be idled. The oil inlet valve port of the second reversing valve is communicated with the oil path to be idled, and the first actuator valve port of the second reversing valve is communicated with the fuel tank; A radiator, which is arranged on the oil path to be idled and located between the second reversing valve and the fuel tank; The hydraulic control system has a standby state and a working state; In the standby state, the first reversing valve is de-energized or reversed to disconnect the path between the oil supply line and the hydraulic actuator, the second reversing valve is energized and reversed to connect the oil path to be idled, the hydraulic oil pump is turned on, and the hydraulic oil circulates in the oil path to be idled; When entering the working state, the first reversing valve is energized and reversed to connect the oil supply line, the second reversing valve is reversed to close the oil path to be idled, and the hydraulic oil circulating in the oil path to be idled and the oil supply line can be directly supplied to the hydraulic actuator.

2. The hydraulic control system according to claim 1, wherein The oil inlet valve port of the first reversing valve is communicated with the hydraulic oil pump, and the actuator valve port of the first reversing valve is communicated with the hydraulic actuator; The hydraulic oil pump is a load-sensitive pump. The output end of the load-sensitive pump is communicated with the oil inlet valve port of the first reversing valve through the oil supply line, and the load-sensitive port of the load-sensitive pump is communicated with the oil return valve port of the first reversing valve through a constant-pressure oil line; Wherein, the second reversing valve is arranged on the oil path to be idled and the constant-pressure oil line. The load-sensitive port of the load-sensitive pump is communicated with the second actuator valve port of the second reversing valve, and the oil return valve port of the second reversing valve is communicated with the oil return valve port of the first reversing valve.

3. The hydraulic control system according to claim 2, characterized in that, Further comprising: A first damping hole, which is arranged on the constant-pressure oil line and located between the second reversing valve and the load-sensitive port; A first check valve. The first check valve is located on the constant-pressure oil line. The connection part of the oil inlet valve port of the first check valve and the constant-pressure oil line is located between the first damping hole and the load-sensitive port, and the connection part of the oil outlet valve port of the first check valve and the constant-pressure oil line is located between the first damping hole and the second actuator valve port of the second reversing valve.

4. The hydraulic control system according to claim 1, wherein Further comprising: A plurality of third reversing valves; The oil supply line includes: A main path, to which the hydraulic oil pump is communicated; A plurality of branch paths, and the plurality of branch paths are communicated with the main path; Among them, the number of the hydraulic actuators is multiple, and each of the branches is correspondingly connected to one or more of the hydraulic actuators and a third reversing valve. The oil return valve port of each third reversing valve communicates with the fuel tank, the oil inlet valve port of each third reversing valve communicates with the main circuit, and each actuator valve port of each third reversing valve communicates with a hydraulic actuator.

5. The hydraulic control system according to any one of claims 1 to 4, characterized in that, Further comprising: A second damping orifice, which is arranged on the standby oil path of the engine oil and is located between the fuel tank and the second reversing valve.

6. The hydraulic control system according to any one of claims 1 to 4, characterized in that, Further comprising: A second one-way valve, which is arranged on the oil supply path and is located between the connection of the standby oil path of the engine oil and the oil supply path and the hydraulic oil pump. The oil inlet valve port of the second one-way valve communicates with the hydraulic oil pump.

7. A fire truck, comprising a chassis, characterized in that, Comprising: Outriggers, which are arranged on the chassis; A boom, which is arranged on the chassis; The hydraulic control system according to any one of claims 1 to 6, wherein the hydraulic actuators of the hydraulic control system include outrigger cylinders and boom cylinders. The outrigger cylinders are connected to the outriggers and are used to drive the outriggers to extend or retract, and the boom cylinders are connected to the boom and are used to drive the boom to extend or retract.

8. A control method for a fire truck during standby operation, characterized in that, For the fire truck according to claim 7, the operation standby control method of the fire truck includes: Receiving the standby instruction of the fire truck and starting the hydraulic oil pump; Controlling the first reversing valve and the second reversing valve to reverse, disconnecting the path between the oil supply path and the hydraulic actuator, and conducting the standby oil path so that the hydraulic oil flows through the standby oil path and returns to the fuel tank; Receiving the operation instruction of the fire truck, controlling the first reversing valve to reverse, and then controlling the second reversing valve to reverse, conducting the oil inlet valve port and the actuator valve port of the first reversing valve, and disconnecting the standby oil path so that the hydraulic oil is supplied to the hydraulic actuator through the oil supply path.

9. The fire truck operation standby control method according to claim 8, wherein, The step of controlling the first reversing valve and the second reversing valve to reverse, disconnecting the path between the oil supply path and the hydraulic actuator, and conducting the standby oil path so that the hydraulic oil flows through the standby oil path and returns to the fuel tank specifically includes: Controlling the first reversing valve and the second reversing valve to be powered off to disconnect the path between the oil supply path and the hydraulic actuator and conduct the standby oil path so that the hydraulic oil flows through the standby oil path and returns to the fuel tank.

10. The fire truck operation standby control method according to claim 8, wherein The hydraulic oil pump is a load-sensing pump. The output end of the load-sensing pump is connected to the oil inlet port of the first reversing valve through the oil supply line, and the load-sensing port of the load-sensing pump is connected to the oil return port of the first reversing valve through a constant-pressure oil line. The second reversing valve is arranged on the standby oil line and the constant-pressure oil line. When the load-sensing port of the load-sensing pump is connected to the second actuator port of the second reversing valve and the oil return port of the second reversing valve is connected to the oil return port of the first reversing valve, upon receiving the operation instruction of the fire truck, the steps of controlling the first reversing valve to change direction and then controlling the second reversing valve to change direction, conducting the oil inlet port and the actuator port of the first reversing valve, and disconnecting the standby oil line so that the hydraulic oil is supplied to the hydraulic actuator through the oil supply line and then returns to the fuel tank specifically include: Receiving the operation instruction of the fire truck and controlling the first reversing valve to change direction so that the oil inlet port of the first reversing valve is conducted to the actuator port; Controlling the second reversing valve to change direction so that the oil return port of the second reversing valve is conducted to the second actuator port of the second reversing valve, and the hydraulic oil is supplied to the hydraulic actuator through the oil supply line and then returns to the load-sensing port through the constant-pressure oil line.

11. The fire truck operation standby control method according to claim 10, characterized in that, The hydraulic control system further includes: a plurality of third reversing valves; the oil supply line includes: a main line and a plurality of branch lines, and the hydraulic oil pump is connected to the main line; the plurality of branch lines are connected to the main line; each branch line is correspondingly connected to one or several hydraulic actuators and one third reversing valve, the oil return port of each third reversing valve is connected to the fuel tank, the oil inlet port of each third reversing valve is connected to the main line, and each actuator port of each third reversing valve is connected to one hydraulic actuator. The fire truck operation standby control method further includes: Receiving a stop operation instruction and controlling the second reversing valve to change direction so that the oil inlet port of the second reversing valve is conducted to the first actuator port of the second reversing valve; When the hydraulic oil supplied by the hydraulic oil pump returns to the fuel tank through the oil return port of the third reversing valve and the first actuator port of the second reversing valve, controlling the first reversing valve to be powered off.

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