Hydraulic driving system for rotating speed self-adaptive control of cooling fan of rail engineering vehicle

Abstract

The invention provides a hydraulic driving system capable of adaptively controlling the rotating speed of a cooling fan of a rail engineering vehicle, which is characterized in that an oil outlet of a hydraulic plunger variable pump is connected with one end of a pressure pipe connected with a hydraulic motor, and the other end of the pressure pipe is communicated with an oil inlet of a temperature control proportional valve group; one oil outlet of each temperature control proportional valve group is communicated with an oil return pipe through a hydraulic oil radiator, the oil return pipe is communicated with a hydraulic oil tank, and two branches of the oil return pipe are respectively communicated with the other oil outlets of the two temperature control proportional valve groups; a safety protection structure connected with the hydraulic motor in parallel is arranged on the pressure pipe, and the hydraulic plunger variable pump is connected with the flow adjusting structure. The system overcomes the defects that when a traditional switching value valve set controls on-off of the cooling fan, system pressure impact is large, and huge noise is generated, system power is dynamically matched in real time according to the heat dissipation requirement, safe operation of a vehicle is ensured, impact force of instant starting and stopping of the cooling fan is reduced, the noise generated by the cooling fan is weakened, and the service life of the vehicle is prolonged. And the traction available power of a vehicle power system is improved.

Description

Technical Field

[0001] The invention belongs to the technical field of rail vehicles, and in particular relates to a hydraulic drive system for adaptively controlling the speed of a cooling fan of a rail engineering vehicle. Background Art

[0002] The existing rail engineering vehicle cooling fan hydraulic drive system adopts a hydraulic metering system of gear pump + gear motor. The gear pump takes power from the engine power output port and is controlled by the switch valve group to drive the hydraulic motor coaxially connected to the cooling fan to rotate, thereby achieving the cooling purpose of the vehicle power system.

[0003] When the power system is in working condition and the water temperature or oil temperature is low, the hydraulic oil output by the hydraulic pump is unloaded through the switch valve group, the hydraulic motor does not work, and the cooling fan coaxially connected to the hydraulic motor does not rotate; when the water temperature or oil temperature of the power system reaches the opening condition requiring heat dissipation, the switch valve group is instantly opened, and the hydraulic oil output by the hydraulic pump drives the gear motor coaxially connected to the cooling fan through the switch valve group to rotate at the maximum working speed under the power system speed. At the moment of opening or closing the switch valve group, the cooling fan speed increases from zero to the maximum working speed or decreases from the maximum working speed to zero in a very short time, and the system pressure increases or decreases sharply instantaneously, resulting in a large pressure shock of the system, and at the same time generates great noise and impact; when the water temperature or oil temperature of the power system is slightly higher than the heat dissipation opening condition, the power system does not need a higher cooling fan working speed to provide high-power cooling, and the higher working speed under the maximum capacity of the system also produces a certain amount of power loss, which consumes and occupies the traction available power of the vehicle power system. Therefore, it is necessary to make improvements to the above problems. Summary of the invention

[0004] The technical problem solved by the present invention is as follows: a hydraulic drive system for adaptively controlling the speed of a cooling fan of a rail engineering vehicle is provided. The system controls the output flow of a hydraulic plunger variable pump according to a real-time water temperature signal of an engine fed back by an electrical system of the vehicle by setting a flow regulating structure, thereby realizing the adjustment of the speed of the cooling fan. The drawbacks of a large system pressure shock and great noise caused by a traditional switch valve group controlling the on and off of the cooling fan are solved. The system power is dynamically matched in real time according to the heat dissipation demand, thereby ensuring the safe operation of the vehicle, reducing the impact force of instantaneous starting and stopping of the cooling fan, reducing the noise generated by the cooling fan, reducing power loss, and improving the traction available power of the vehicle power system.

[0005] The technical solution adopted by the present invention is a hydraulic drive system for adaptively controlling the speed of a cooling fan of a rail engineering vehicle, comprising a hydraulic oil tank, two hydraulic plunger variable pumps connected in series and connected to the engine power output ports in a hydraulic transmission system and an electric transmission system, and two hydraulic motors coaxially connected to the cooling fans in the hydraulic transmission system and the electric transmission system, respectively. The oil suction ports of the two hydraulic plunger variable pumps are connected to the hydraulic oil tank through an oil suction pipe equipped with an oil suction filter, the oil outlet of the hydraulic plunger variable pump is connected to one end of a pressure pipe connected to the hydraulic motor, and the other end of the pressure pipe is connected to the inlet of a temperature control proportional valve group. The oil ports are connected, one oil outlet of the two groups of temperature-controlled proportional valve groups is connected to the oil return pipe via the hydraulic oil radiator, and the oil return pipe is connected to the hydraulic oil tank through the oil return filter, and the two branches of the oil return pipe are respectively connected to the other oil outlet of the two temperature-controlled proportional valve groups; the pressure pipe is provided with a safety protection structure which is connected in parallel with the hydraulic motor and is used to prevent the hydraulic motor from instantaneously sucking air and limiting the maximum working pressure of the hydraulic motor, and the flow regulating structure connected to the hydraulic plunger variable pump controls the output flow of the hydraulic plunger variable pump according to the real-time water temperature signal of the engine fed back by the vehicle electrical system, thereby realizing the adjustment of the cooling fan speed.

[0006] Among them, the flow regulating structure includes a pressure-compensating electric proportional control valve, the control pressure oil inlet of the pressure-compensating electric proportional control valve is connected to one end of the pressure pipe through a branch oil pipe, and the control pressure oil outlet of the pressure-compensating electric proportional control valve is connected to the variable mechanism of the hydraulic plunger variable pump, and the oil drain port of the pressure-compensating electric proportional control valve is connected to the hydraulic oil tank through the hydraulic pump oil drain pipe.

[0007] Furthermore, the safety protection structure comprises an anti-vacuum one-way valve and a safety valve, and the vacuum one-way valve, the safety valve and the hydraulic motor are connected in parallel to the pressure pipe.

[0008] Furthermore, the oil drain ports of the two hydraulic motors are connected to the hydraulic oil tank through motor oil drain pipes.

[0009] Furthermore, the oil suction pipe is a Y-shaped pipeline, and the oil suction filter is installed on the main pipeline connected to the hydraulic oil tank, and the two branches of the oil suction pipe are respectively connected to the oil suction ports of two hydraulic piston variable pumps.

[0010] Furthermore, the hydraulic oil tank is provided with a level and temperature gauge for measuring the internal oil level and temperature and an air filter for filtering the air sucked into the interior.

[0011] The advantages of the present invention compared with the prior art are:

[0012] 1. This technical solution is based on the electric proportional pressure compensation of the pressure compensation electric proportional control valve to control the flow of the hydraulic plunger variable pump connected to the hydraulic motor, thereby realizing the speed adjustment of the cooling fan coaxially connected to the hydraulic motor, reducing the pressure shock, reducing the impact force of the instantaneous start and stop of the cooling fan, and reducing the noise generated;

[0013] 2. This technical solution introduces the real-time temperature electrical signal of the engine water temperature detected by the original vehicle electrical control system, and uses it as the input signal for the pressure compensation electric proportional control valve to control the output oil pressure of the hydraulic plunger variable pump, thereby realizing adaptive control of the cooling fan speed according to the real-time detected power system water temperature and oil temperature, and dynamically matching and adjusting the cooling fan speed in real time according to the cooling demand, realizing energy saving of the hydraulic system, reducing power loss, and improving the traction available power of the vehicle power system;

[0014] 3. This technical solution has a simple structure and novel design. It solves the drawbacks of large system pressure shock and great noise caused by the traditional switch valve group controlling the on and off of the cooling fan. It dynamically matches the system power in real time according to the heat dissipation requirements, ensures the safe operation of the vehicle through the set safety protection structure, reduces the impact force of the instantaneous start and stop of the cooling fan, weakens the noise it generates, reduces power loss, and improves the traction available power of the vehicle power system. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 This is the control principle diagram of the present invention. DETAILED DESCRIPTION

[0016] The following will be combined with the embodiments of the present invention Figure 1 , the technical solutions in the embodiments of the present invention are clearly and completely described. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0017] It should be noted that, in this document, unless otherwise stated, it should be understood that the terms "center", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", "third", etc., are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0018] In this document, the terms "comprises", "comprising" or any other variation thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further limitations. The elements defined by the sentence "comprising a ..." do not exclude the presence of other identical elements in the process, method, article or device comprising the elements.

[0019] Hydraulic drive system for adaptive speed control of cooling fan of rail engineering vehicles, such as Figure 1 As shown, it includes a hydraulic oil tank 1, two hydraulic piston variable pumps 3 connected in series and connected to the engine power output ports in the hydraulic transmission system and the electric transmission system, and two hydraulic motors 6 coaxially connected to the cooling fans 8 in the hydraulic transmission system and the electric transmission system, respectively. The suction ports of the two hydraulic piston variable pumps 3 are connected to the hydraulic oil tank 1 through the suction pipe 18 equipped with the suction filter 2, the oil outlet of the hydraulic piston variable pump 3 is connected to one end of the pressure pipe 7 connected to the hydraulic motor 6, and the other end of the pressure pipe 7 is connected to the oil inlet of the temperature control proportional valve group 11, one oil outlet of the two groups of the temperature control proportional valve groups 11 is connected to the return oil pipe 13 through the hydraulic oil radiator 12, and the return oil pipe 13 is connected to the hydraulic oil tank 1 through the return oil filter 14, and the two branches of the return oil pipe 13 are connected to the hydraulic oil tank 1. The pressure pipe 7 is connected to the other oil outlet of the two temperature-controlled proportional valve groups 11 respectively; the pressure pipe 7 is provided with a safety protection structure connected in parallel with the hydraulic motor 6 and used to prevent the hydraulic motor 6 from instantaneously sucking air and limiting the maximum working pressure of the hydraulic motor 6, and the flow regulating structure connected to the hydraulic plunger variable pump 3 controls the output flow of the hydraulic plunger variable pump 3 according to the real-time water temperature signal of the engine fed back by the vehicle electrical system, thereby realizing the adjustment of the speed of the cooling fan 8; in the above structure, the electric proportional pressure compensation based on the pressure compensation electric proportional control valve 4 controls the flow of the hydraulic plunger variable pump 3 connected to the hydraulic motor 6, thereby realizing the speed adjustment of the cooling fan 8 coaxially connected to the hydraulic motor 6, reducing pressure shock, reducing the impact force of the instantaneous start and stop of the cooling fan, and reducing the noise generated by it;

[0020] The specific structure of the flow regulating structure is as follows: the flow regulating structure includes a pressure-compensating electric proportional control valve 4, the control pressure oil inlet of the pressure-compensating electric proportional control valve 4 is connected to one end of the pressure pipe 7 through a branch oil pipe, and the control pressure oil outlet of the pressure-compensating electric proportional control valve 4 is connected to the variable mechanism of the hydraulic plunger variable pump 3, and the drain port of the pressure-compensating electric proportional control valve 4 is connected to the hydraulic oil tank 1 through the hydraulic pump drain pipe 15; in the above structure, by introducing the real-time temperature electrical signal of the engine water temperature detected by the original vehicle electrical control system, it is used as an input signal for the pressure-compensating electric proportional control valve 4 to control the output oil pressure of the hydraulic plunger variable pump 3, thereby realizing adaptive control of the speed of the cooling fan 8 according to the real-time detected water temperature and oil temperature of the power system, and dynamically matching and adjusting the speed of the cooling fan 8 in real time according to the cooling demand, realizing energy saving of the hydraulic system, reducing power loss, and improving the traction available power of the vehicle power system;

[0021] The specific safety protection structure is as follows: the safety protection structure includes an anti-cavitation check valve 9 and a safety valve 10, and the air suction check valve 9, the safety valve 10 and the hydraulic motor 6 are connected in parallel to the pressure pipe 7; with the above structure, when the engine stops, the hydraulic plunger variable pump 3 will stop running, and the hydraulic oil cannot be output at this time. In order to prevent the rotating cooling fan 8 from continuing to rotate the hydraulic motor 6 by inertia and causing it to be instantaneously cavitated, an anti-cavitation check valve 9 is set. At this time, the return oil of the hydraulic motor 6 can enter the oil inlet side through the anti-cavitation check valve 9 to replenish oil, so as to avoid damage to the hydraulic motor 6 due to instantaneous cavitation. At the same time, the oil inlet and outlet of the hydraulic motor 6 are connected in parallel with the safety valve 10 to limit the maximum working pressure of the hydraulic motor 6 and ensure that the cooling fan 8 does not exceed the maximum working speed.

[0022] Among them, the oil drain ports of the two hydraulic motors 6 are connected to the hydraulic oil tank 1 through the motor oil drain pipe 5; specifically, the oil suction pipe 18 is a Y-shaped pipeline, and the oil suction filter 2 is installed on the main pipeline connected to the hydraulic oil tank 1, and the two branches of the oil suction pipe 18 are respectively connected to the oil suction ports of the two hydraulic plunger variable pumps 3; specifically, the hydraulic oil tank 1 is provided with a level and temperature gauge 17 for measuring the internal oil level and temperature and an air filter 16 for filtering the air sucked into the interior.

[0023] The transmission forms of rail engineering vehicles are mainly hydraulic transmission and electric transmission. The power system of hydraulic transmission is mainly the engine and the hydraulic transmission. The cooling fan of the power system is divided into the engine cooling fan and the hydraulic transmission cooling fan. The power system of electric transmission is mainly the engine and the generator. The cooling fan of the power system is divided into the engine cooling fan and the generator cooling fan. The cooling fan 8 is coaxially mechanically connected with the corresponding hydraulic motor 6, and the hydraulic plunger variable pump 3 is coaxially mechanically connected with the power output port of the engine. The hydraulic plunger variable pump 3 takes power from the power output port of the engine and rotates. In addition to the above structure, it can also be driven by the power take-off port of the hydraulic transmission or the power take-off port of the generator; the suction port of the hydraulic plunger variable pump 3 draws oil from the hydraulic oil tank 1 and enters the suction side plunger volume chamber of the hydraulic plunger variable pump 3 after being filtered by the suction filter 2, and enters the oil outlet side plunger volume chamber after rotation, and enters the oil inlet of the hydraulic motor 6 from the oil outlet of the hydraulic plunger variable pump 3 through the pressure pipe 7, driving its rotational movement, thereby driving the cooling The fan 8 rotates, and the return oil from the oil outlet of the hydraulic motor 6 passes through the temperature control proportional valve group 11. When the temperature of the hydraulic oil returning to the oil is low, the temperature control proportional valve group 11 is in the left position, and the hydraulic oil returns to the hydraulic oil tank 1 through the return oil pipe 13 and the return oil filter 14. If the temperature of the hydraulic oil returning to the oil gradually increases, the temperature control proportional valve group 11 can move linearly from the left position to the right position as the oil temperature increases. The valve core of the temperature control proportional valve group 11 is within the middle area of ​​the valve body, and a part of the hydraulic oil returns to the oil tank 1 through the return oil pipe 13 and the return oil filter 14. The hydraulic oil tank 1, the other part of the hydraulic oil through the hydraulic oil radiator 13, the return oil pipe 13 and the return oil filter 14 back to the hydraulic oil tank 1, so as to maintain the temperature of the hydraulic oil in the best state, ensure the hydraulic oil at the best kinematic viscosity, and improve the service life of the hydraulic components. If the oil temperature is very high, the valve core of the temperature control proportional valve group 11 will be in the right position of the valve body, and all the return oil of the hydraulic motor 6 will be returned to the hydraulic oil tank 1 through the hydraulic oil radiator 12, the return oil pipe 13 and the return oil filter 14, so as to achieve full heat dissipation of the hydraulic return oil.

[0024] When the power system is started, the vehicle electrical control system will provide a large current signal to the pressure-compensating electric proportional control valve 4 through the controller in advance, so that the control pressure of the pressure-compensating electric proportional control valve 4 is maintained at the minimum pressure. As the engine starts, the engine will drive the hydraulic plunger variable pump 3 to rotate, and the output pressure oil will drive the hydraulic motor 6 to rotate at the lowest speed. When the power system continues to run and the temperature gradually rises, the real-time dynamic detection of the engine water temperature signal and the hydraulic transmission (or generator) oil temperature signal will be respectively output through the controller to give the corresponding and gradually decreasing current signals to the pressure-compensating electric proportional control valve 4. The pressure of the control system of the pressure-compensating electric proportional control valve 4 gradually increases, pushing its valve core linearly. It moves left, and the variable piston of the hydraulic plunger variable pump 3 moves toward the rodless chamber, the swash plate angle increases, the output flow of the hydraulic pump increases, and the speed of the driving hydraulic motor 6 gradually increases, and the speed of the cooling fan 8 increases accordingly, until the load pressure is balanced with the control pressure, and the control pressure is balanced with the real-time dynamic detection of the power system water temperature and oil temperature, and the current size and control pressure of the pressure compensation electric proportional control valve 4 are linearly adjusted in real time according to the real-time dynamic detection of the power temperature signal, so as to realize the adaptive control of the speed of the cooling fan 8, reduce the system impact, output the system power according to the heat dissipation demand, realize the energy saving of the hydraulic system, and thus reduce the power loss. Among them, in this scheme, the hydraulic motor 6 can be bidirectional or unidirectional.

[0025] In order to ensure that the vehicle can operate normally when the electrical control system fails or the power system temperature detection signal is abnormal, the pressure-compensating electric proportional control valve 4 adopts an inverse proportional characteristic. The smaller the input current, the higher the system pressure and the faster the cooling fan 8 speed. The larger the input current, the lower the system pressure and the lower the cooling fan 8 speed. When there is no current signal input, the pressure-compensating electric proportional control valve 4 automatically maintains the preset maximum system pressure of the spring to ensure that the cooling fan 8 can continue to operate at the maximum operating speed, thereby ensuring the safe operation of the vehicle.

[0026] This technical solution has a simple structure and novel design. It solves the drawbacks of large system pressure shock and great noise caused by the traditional on-off valve group controlling the cooling fan to turn on and off. It dynamically matches the system power in real time according to the heat dissipation requirements, ensures the safe operation of the vehicle through the set safety protection structure, reduces the impact force of the instantaneous start and stop of the cooling fan, weakens the noise it generates, reduces power loss, and improves the traction available power of the vehicle power system.

[0027] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other specific forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations falling within the meaning and scope of the equivalent elements of the claims be included in the invention. Any reference numeral in a claim should not be considered as limiting the claim to which it relates.

[0028] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A hydraulic drive system with adaptive speed control of cooling fan of rail engineering vehicles, characterized by: The invention comprises a hydraulic oil tank (1), two hydraulic piston variable pumps (3) connected in series with each other and connected to the engine power output ports in the hydraulic transmission system and the electric transmission system, and two hydraulic motors (6) mechanically coaxially connected to the cooling fans (8) in the hydraulic transmission system and the electric transmission system, respectively. The hydraulic motors (6) are unidirectional hydraulic motors or bidirectional hydraulic motors. The oil suction ports of the two hydraulic piston variable pumps (3) are connected to the hydraulic oil tank (1) through an oil suction pipe (18) equipped with an oil suction filter (2) on the main road. The oil outlet of the hydraulic piston variable pump (3) is connected to one end of a pressure pipe (7) connected to the hydraulic motor (6), and the other end of the pressure pipe (7) is connected to the oil inlet of a temperature control proportional valve group (11). The two groups of the hydraulic piston variable pumps (3) are connected to the hydraulic oil tank (1) through an oil suction pipe (18) equipped with an oil suction filter (2) on the main road. The oil outlet of the hydraulic piston variable pump (3) is connected to one end of a pressure pipe (7) connected to the hydraulic motor (6), and the other end of the pressure pipe (7) is connected to the oil inlet of a temperature control proportional valve group (11). An oil outlet of the temperature-controlled proportional valve group (11) is connected to an oil return pipe (13) via a hydraulic oil radiator (12), and the oil return pipe (13) is connected to a hydraulic oil tank (1) via an oil return filter (14), and two branches of the oil return pipe (13) are respectively connected to another oil outlet of two temperature-controlled proportional valve groups (11); the pressure pipe (7) is provided with a safety protection structure connected in parallel with the hydraulic motor (6) and used to prevent the hydraulic motor (6) from instantaneously sucking air and limiting the maximum working pressure of the hydraulic motor (6); and a flow regulating structure connected to the hydraulic plunger variable pump (3) controls the output flow of the hydraulic plunger variable pump (3) according to a real-time engine water temperature signal fed back by the vehicle electrical system, thereby realizing the adjustment of the speed of the cooling fan (8).

2. The hydraulic drive system for adaptively controlling the speed of a cooling fan of a rail engineering vehicle according to claim 1, characterized in that: The flow regulating structure comprises a pressure-compensating electric proportional control valve (4), wherein a control pressure oil inlet of the pressure-compensating electric proportional control valve (4) is connected to one end of a pressure pipe (7) via a branch oil pipe, and a control pressure oil outlet of the pressure-compensating electric proportional control valve (4) is connected to a variable mechanism of a hydraulic plunger variable pump (3), and an oil drain port of the pressure-compensating electric proportional control valve (4) is connected to a hydraulic oil tank (1) via a hydraulic pump oil drain pipe (15).

3. The hydraulic drive system for adaptively controlling the speed of a cooling fan of a rail engineering vehicle according to claim 1, characterized in that: The safety protection structure comprises an anti-vacuum check valve (9) and a safety valve (10), and the vacuum check valve (9), the safety valve (10) and the hydraulic motor (6) are connected in parallel to the pressure pipe (7).

4. The hydraulic drive system for adaptively controlling the speed of a cooling fan of a rail engineering vehicle according to claim 1, characterized in that: The oil drain ports of the two hydraulic motors (6) are connected to the hydraulic oil tank (1) via motor oil drain pipes (5).

5. The hydraulic drive system for adaptively controlling the speed of a cooling fan of a rail engineering vehicle according to claim 1, characterized in that: The oil suction pipe (18) is a Y-shaped pipeline, and the oil suction filter (2) is installed on a main pipeline connected to the hydraulic oil tank (1), while the two branches of the oil suction pipe (18) are respectively connected to the oil suction ports of two hydraulic piston variable pumps (3).

6. The hydraulic drive system for adaptively controlling the speed of a cooling fan of a rail engineering vehicle according to any one of claims 1 to 5, characterized in that: The hydraulic oil tank (1) is provided with a level and temperature gauge (17) for measuring the internal oil level and temperature, and an air filter (16) for filtering the air sucked into the internal part.

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