Hydraulic heat dissipation loop

Abstract

The utility model discloses a hydraulic heat dissipation loop, which relates to the technical field of hydraulic drive heat management of railway maintenance machinery, and comprises a heat dissipation pump, a hydraulic oil tank, a radiator, a flow control valve, a pressure control valve, a temperature control valve and a temperature sensor, the heat dissipation pump is driven by an engine; the radiator comprises a cooling chamber and a hydraulic motor, a fan is arranged on an output shaft of the hydraulic motor, and the hydraulic motor drives the fan to radiate heat of hydraulic oil entering the cooling chamber; the flow control valve is installed at an oil outlet of the heat dissipation pump and used for adjusting flow. The pressure control valve is connected with an oil inlet of the hydraulic motor in parallel and used for adjusting pressure of the hydraulic motor. The temperature control valve is installed at an oil inlet of the cooling chamber and used for controlling the hydraulic flow entering the cooling chamber. The temperature sensor is installed on the hydraulic oil tank and used for monitoring the system hydraulic oil temperature.

Description

Technical Field

[0001] The utility model relates to the technical field of hydraulic drive thermal management of railway maintenance machinery, in particular to a hydraulic heat dissipation circuit. Background Art

[0002] Hydraulic transmission is one of the most commonly used transmission methods for railway maintenance machinery. It has a wide speed adjustment range and can achieve stepless speed regulation. At present, railway maintenance machinery mainly adopts two speed regulation modes: throttling and volumetric speed regulation. The principle of throttling speed regulation is that the output flow of the oil pump is constant, and the flow area of ​​the flow control element in the circuit is changed to change the flow entering the actuator to achieve the purpose of speed regulation; the principle of volumetric speed regulation is to adjust the speed of the actuator by changing the displacement of the variable pump or variable motor in the circuit.

[0003] The railway rescue crane requires the operator to adjust the operating speed of each mechanism of the crane in real time according to the actual operating conditions during its operation. Therefore, the speed regulation mode is adopted in which the operator controls the engine throttle to change the engine output speed and the oil pump output flow to control the mechanism operating speed. This method can achieve stepless speed regulation, simple operation, and simple component structure, but it will change the output speed of all oil pumps synchronously. For the cooling system, the cooling fan speed should only change with the change of system oil temperature.

[0004] Therefore, it is necessary to design a hydraulic heat dissipation circuit that can make the cooling fan speed unaffected by changes in the oil supply flow rate and automatically adjust the cooling fan speed according to the hydraulic system oil temperature. Utility Model Content

[0005] In view of the defects existing in the prior art, the purpose of the utility model is to provide a hydraulic heat dissipation circuit, so that the speed of the heat dissipation fan is automatically adjusted according to the system oil temperature without being affected by the change of the oil supply flow rate.

[0006] In order to achieve the above purpose, the technical solution adopted by the utility model is: a hydraulic heat dissipation circuit, including a heat dissipation pump, a hydraulic oil tank and a radiator, and also including a flow control valve, a pressure control valve, a temperature control valve and a temperature sensor; the heat dissipation pump is driven by an engine; the radiator includes a cooling chamber and a hydraulic motor, and a fan is arranged on the output shaft of the hydraulic motor, and the fan is driven by the hydraulic motor to dissipate the heat of the hydraulic oil entering the cooling chamber; the flow control valve is installed at the oil outlet of the heat dissipation pump, and is used to adjust the maximum flow of driving the hydraulic motor; the pressure control valve is connected in parallel with the oil inlet of the hydraulic motor, and is used to adjust the working pressure of the hydraulic motor; the temperature control valve is installed at the oil inlet of the cooling chamber, and is used to control the flow of hydraulic oil entering the cooling chamber; the temperature sensor is installed on the hydraulic oil tank to monitor the hydraulic oil temperature of the system.

[0007] On the basis of the above technical solution, the heat dissipation pump is connected to the engine through a transfer case, and the oil suction port of the heat dissipation pump is connected to the oil suction port of the hydraulic oil tank through a pipeline.

[0008] On the basis of the above technical solution, the heat dissipation pump is a fixed-flow pump or a variable-flow pump.

[0009] On the basis of the above technical solution, the flow control valve includes a PR oil inlet, a REG priority port and a bypass port BP. The PR oil inlet is connected to the oil outlet of the heat pump through a pipeline; the REG priority port is connected to the oil inlet of the hydraulic motor and the oil inlet of the pressure control valve through pipelines; the bypass port BP is connected to the oil inlet of the temperature control valve and the oil outlet of the pressure control valve through pipelines.

[0010] On the basis of the above technical solution, the flow control valve is an overflow throttle valve, including a flow regulating hand wheel for adjusting the output flow size of the REG priority port, and the REG priority port is also integrated with a safety valve.

[0011] On the basis of the above technical solution, the cooling port of the temperature control valve is connected to the oil inlet of the cooling chamber through a pipeline; the bypass port of the temperature control valve is connected to the oil return port of the hydraulic oil tank through a pipeline.

[0012] On the basis of the above technical solution, the temperature control valve is a two-position three-way proportional valve, which pushes the valve core through the thermal expansion and contraction of the temperature-sensitive material at the end of the valve core to control the heat-dissipated hydraulic oil to enter the radiator or return to the hydraulic oil tank.

[0013] Based on the above technical solution, the pressure control valve is an inverse proportional pilot electromagnetic overflow valve, including a main valve and a pilot valve, and the pressure control valve is also integrated with a back-suction check valve, which can prevent the hydraulic motor from being damaged by air suction after the cooling pump stops supplying oil.

[0014] On the basis of the above technical solution, the oil outlet of the cooling chamber and the oil outlet of the hydraulic motor are connected to the oil return port of the hydraulic oil tank through a pipeline after merging.

[0015] On the basis of the above technical solution, the hydraulic oil tank is also provided with an oil suction filter, an oil return filter, a liquid level gauge and an air filter; the oil suction filter can keep the oil entering the hydraulic system clean, the oil return filter can block impurities in the hydraulic system from entering the hydraulic oil tank, the liquid level gauge facilitates observation of the liquid level in the hydraulic oil tank, and the air filter prevents pollutants in the atmosphere from entering the hydraulic oil tank.

[0016] The beneficial effects of the utility model are:

[0017] In the utility model, the change of the output flow of the heat pump does not affect the speed of the radiator cooling fan, and the heat dissipation of the hydraulic oil is adjusted in real time according to the system oil temperature, ensuring that the hydraulic system oil temperature is within an optimal range. At the same time, the components are simple in structure and low in cost. The utility model is suitable for the speed regulation mode of the operating system that controls the output flow of the hydraulic pump by changing the engine speed, but requires the heat dissipation power of the heat dissipation system to be not affected by the change of the oil supply flow. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a schematic diagram of the structure of the hydraulic heat dissipation circuit in the embodiment of the utility model;

[0019] Figure 2 It is a hydraulic principle diagram of the hydraulic heat dissipation circuit in the embodiment of the utility model;

[0020] Figure 3 This is a structural diagram of a flow control valve of a hydraulic heat dissipation circuit in an embodiment of the utility model;

[0021] Figure 4 This is an outline diagram of a pressure regulating valve of a hydraulic heat dissipation circuit in an embodiment of the utility model;

[0022] Figure 5 This is an appearance diagram of the radiator of the hydraulic heat dissipation circuit in the embodiment of the utility model.

[0023] Reference numerals:

[0024] 1-engine; 2-cooling pump; 3-hydraulic oil tank;

[0025] 4-flow control valve; 4.1-flow adjustment hand wheel; 4.2-PR oil inlet; 4.3-REG priority port; 4.4-BP bypass port;

[0026] 5-pressure control valve; 5.1-pilot valve; 5.2-main valve; 5.3-reverse suction check valve;

[0027] 6- Temperature control valve;

[0028] 7- Radiator; 7.1- Hydraulic motor; 7.2- Cooling chamber; 7.3- Fan;

[0029] 8- Temperature sensor;

[0030] 9-Controller. DETAILED DESCRIPTION

[0031] The embodiments of the present invention are described in detail below. The embodiments are shown in the accompanying drawings, wherein the same or similar numbers throughout represent the same or similar elements or elements with the same or similar functions.

[0032] In the description of the present invention, it should be noted that directional words, such as the terms "center", "lateral (X)", "longitudinal (Y)", "vertical (Z)", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", etc., indicating directions and positional relationships are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of narrating 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 cannot be understood as limiting the specific protection scope of the present invention.

[0033] The following is a further description of the specific implementation of the utility model in conjunction with the drawings of the specification, so that the technical solution and its beneficial effects of the utility model are clearer and more explicit. The following description of the embodiments with reference to the drawings is exemplary and intended to explain the utility model, but cannot be understood as limiting the utility model.

[0034] See also Figure 1 and Figure 2 As shown, an embodiment of the utility model provides a hydraulic heat dissipation circuit, including a heat dissipation pump 2, a hydraulic oil tank 3 and a radiator 7, and also includes a flow control valve 4, a pressure control valve 5, a temperature control valve 6, a temperature sensor 8 and a controller 9.

[0035] The heat pump 2 is driven by the engine 1; specifically, the heat pump 2 is a fixed displacement pump (gear pump, vane pump) or a variable displacement piston pump. The heat pump 2 is connected to the engine 1 through a transfer case, the engine speed is continuously adjustable through the accelerator pedal, and the oil suction port of the heat pump 2 is connected to the oil suction port of the hydraulic oil tank 3 through a pipeline.

[0036] See also Figure 5 As shown, the radiator 7 includes a cooling chamber 7.2 and a hydraulic motor 7.1, and a fan 7.3 is arranged on the output shaft of the hydraulic motor 7.1, and the fan 7.3 is driven by the hydraulic motor 7.1 to dissipate heat of the hydraulic oil entering the cooling chamber 7.2; specifically, the oil outlet of the cooling chamber 7.2 and the oil outlet T of the hydraulic motor 7.1 are connected to the return oil port of the hydraulic oil tank 3 through a pipeline after merging.

[0037] The flow control valve 4 is installed at the oil outlet of the heat pump 2 to adjust the maximum flow of the driving hydraulic motor 7.1; see Figure 2 and Figure 3As shown, the flow control valve 4 includes a PR oil inlet 4.2, a REG priority port 4.3 and a BP bypass port 4.4. The PR oil inlet 4.2 is connected to the oil outlet of the heat pump 2 through a pipeline; the REG priority port 4.3 is connected to the oil inlet P of the hydraulic motor 7.1 and the oil inlet A of the pressure control valve 5 through a pipeline (including a three-way joint); the BP bypass port 4.4 is connected to the oil inlet IN of the temperature control valve 6 and the oil outlet B of the pressure control valve 5 through a pipeline (including a three-way joint). Specifically, the flow control valve 4 is a relief throttle valve, including a flow adjustment hand wheel 4.1 for adjusting the output flow of the REG priority port 4.3, and the REG priority port 4.3 is also integrated with a safety valve to prevent the flow control valve from being damaged when the load is overloaded. The valve can adjust the output flow of the REG priority port by a hand wheel. After adjustment, the output flow of the REG priority port remains unchanged when the load changes and the PR oil inlet flow changes.

[0038] The pressure control valve 5 is connected in parallel with the oil inlet of the hydraulic motor 7.1 and is used to adjust the working pressure of the hydraulic motor 7.1; see Figure 2 and Figure 4 As shown, the pressure control valve 5 is an inverse proportional pilot electromagnetic relief valve, including a main valve 5.2 and a pilot valve 5.1, and the pressure control valve 5 is also integrated with a back-suction check valve 5.3, which can prevent the hydraulic motor 7.1 from being damaged by suction after the heat pump 2 stops supplying oil. The overflow pressure of the inverse proportional pilot electromagnetic relief valve is controlled by current proportion, and the overflow pressure of the main valve decreases as the pilot valve control current increases. When the control current is zero, the main valve set pressure reaches the maximum value, and the magnitude of the control current changes with the oil temperature monitored by the pressure sensor.

[0039] The temperature control valve 6 is installed at the oil inlet of the cooling chamber 7.2, and is used to control the flow of hydraulic oil entering the cooling chamber 7.2; specifically, the cooling port C of the temperature control valve 6 is connected to the oil inlet of the cooling chamber 7.2 through a pipeline; the bypass port T of the temperature control valve 6 is connected to the oil return port of the hydraulic oil tank 3 through a pipeline. The temperature control valve 6 is a two-position three-way proportional valve, and the temperature-sensitive material at the end of the valve core expands and contracts to push the valve core to control the heat-dissipated hydraulic oil to enter the radiator 7 or return to the hydraulic oil tank 3. When the temperature of the temperature control valve is lower than the lower limit of the set range, the heat-dissipated hydraulic oil directly enters the hydraulic oil tank without heat dissipation; when the temperature is within the set range, the heat-dissipated hydraulic oil partially enters the hydraulic oil tank and partially enters the radiator for heat dissipation; when the temperature exceeds the upper limit of the set range, the heat-dissipated hydraulic oil all enters the radiator for heat dissipation. Preferably, the temperature control valve is also provided with a bypass relief valve. When the valve core of the temperature control valve is stuck, the bypass relief valve opens when the return oil pressure reaches 50PSI to protect the system from damage due to excessive pressure.

[0040] The temperature sensor 8 is installed on the hydraulic oil tank 3 to monitor the temperature of the hydraulic oil in the system. The temperature sensor is installed on the hydraulic oil tank, and the contactor is immersed in the hydraulic oil to monitor the hydraulic oil temperature in real time and provide real-time feedback to the controller 9.

[0041] The controller 9 calculates the output control current according to the input signal of the temperature sensor 8 through the program to control the overflow pressure of the pressure control valve. Specifically, the controller 9 is program-controlled and can output the control current after calculation according to the output signal of the temperature sensor 8 to control the pilot valve 5.1 of the pressure control valve 5. When the oil temperature is lower than the lower limit of the set range, the maximum current is output and the overflow pressure of the overflow valve is zero; when the oil temperature is higher than the upper limit of the set value, the output current is zero and the overflow pressure of the overflow valve is maximum; when the oil temperature is within the set range, the output current changes according to the oil temperature. Specifically, the hydraulic oil tank 3 is also provided with an oil suction filter, an oil return filter, a liquid level gauge and an air filter; the oil suction filter can keep the oil entering the hydraulic system clean, the oil return filter can block impurities in the hydraulic system from entering the hydraulic oil tank 3, the liquid level gauge is convenient for observing the liquid level in the hydraulic oil tank 3, and the air filter prevents pollutants in the atmosphere from entering the hydraulic oil tank 3.

[0042] The parameter calibration process of each valve component in the hydraulic cooling circuit is as follows:

[0043] First, calibrate the maximum overflow pressure of the pressure control valve according to the lowest rated pressure of each hydraulic component, then adjust the flow control valve handwheel according to the maximum speed of the radiator cooling fan, and stop adjusting when the cooling fan speed reaches the maximum value.

[0044] When the oil temperature detected by the temperature sensor on the oil tank is lower than the lower limit of the system set temperature range, the current input to the pressure control valve by the controller is the largest, and the overflow valve of the pressure control valve is fully open. The flow output from the priority port of the flow control valve REG enters the temperature control valve through the overflow valve, and the hydraulic motor does not work. At this time, the temperature control valve temperature sensing material does not expand, and the valve core of the temperature control valve is in the normally open bypass port T under the action of the spring reset, and the heat-dissipated hydraulic oil returns to the oil tank without passing through the radiator.

[0045] When the oil temperature detected by the temperature sensor on the oil tank is at the upper limit of the system set temperature, the current input to the pressure control valve by the controller is zero, and the pressure of the overflow valve of the pressure control valve reaches the maximum set value. The flow output from the priority port of the flow control valve REG all enters the hydraulic motor, and the hydraulic motor drives the cooling fan to reach the maximum speed. At this time, the volume of the temperature-sensitive material of the temperature control valve expands to the maximum, and the valve core of the temperature control valve is in the normally open cooling port C under the push of the temperature-sensitive material. The hydraulic oil that is cooled all enters the cooling chamber of the radiator for heat dissipation and then returns to the oil tank.

[0046] When the oil temperature detected by the temperature sensor on the oil tank is within the system set temperature range, the current input to the pressure control valve by the controller changes according to the oil temperature. At this time, the pressure of the pressure control valve relief valve changes with the current. The flow output from the priority port of the flow control valve REG partially drives the hydraulic motor according to the speed demand of the cooling fan, and partially overflows through the pressure control valve. The speed of the cooling fan is in a dynamic adjustment state. At this time, the volume of the temperature-sensitive material of the temperature control valve partially expands. Under the push of the temperature-sensitive material, the valve core of the temperature control valve partially passes through the cooling port C and partially passes through the bypass port T. The hydraulic oil that is cooled enters the radiator cooling chamber to dissipate heat and then returns to the oil tank, and partially returns directly to the hydraulic oil tank.

[0047] In the description of the specification, the description with reference to the terms "one embodiment", "preferably", "example", "specific example" or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the utility model, and the schematic expressions of the above terms in this specification do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0048] The present invention is not limited to the above-mentioned embodiments. For ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications are also considered to be within the scope of protection of the present invention. The contents not described in detail in this specification belong to the prior art known to professional and technical personnel in this field.

Claims

1. A hydraulic heat dissipation circuit, comprising a heat dissipation pump (2), a hydraulic oil tank (3) and a radiator (7), characterized in that: It also includes a flow control valve (4), a pressure control valve (5), a temperature control valve (6) and a temperature sensor (8); The heat dissipation pump (2) is driven by the engine (1); The radiator (7) comprises a cooling chamber (7.2) and a hydraulic motor (7.1), and a fan (7.3) is arranged on the output shaft of the hydraulic motor (7.1), and the fan (7.3) is driven by the hydraulic motor (7.1) to dissipate heat from the hydraulic oil entering the cooling chamber (7.2); The flow control valve (4) is installed at the oil outlet of the heat dissipation pump (2) and is used to adjust the maximum flow of the driving hydraulic motor (7.1); The pressure control valve (5) is connected in parallel with the oil inlet of the hydraulic motor (7.1) and is used to adjust the working pressure of the hydraulic motor (7.1); The temperature control valve (6) is installed at the oil inlet of the cooling chamber (7.2) and is used to control the flow rate of hydraulic oil entering the cooling chamber (7.2); The temperature sensor (8) is installed on the hydraulic oil tank (3) to monitor the temperature of the hydraulic oil in the system.

2. The hydraulic heat dissipation circuit according to claim 1, characterized in that: The heat dissipation pump (2) is connected to the engine (1) via a transfer case, and the oil suction port of the heat dissipation pump (2) is connected to the oil suction port of the hydraulic oil tank (3) via a pipeline.

3. The hydraulic heat dissipation circuit according to claim 2, characterized in that: The heat dissipation pump (2) is a fixed-displacement pump or a variable-displacement pump.

4. The hydraulic heat dissipation circuit according to claim 1, characterized in that: The flow control valve (4) comprises a PR oil inlet (4.2), a REG priority port (4.3) and a BP bypass port (4.4); the PR oil inlet (4.2) is connected to the oil outlet of the heat dissipation pump (2) through a pipeline; the REG priority port (4.3) is respectively connected to the oil inlet of the hydraulic motor (7.1) and the oil inlet of the pressure control valve (5) through pipelines; and the BP bypass port (4.4) is respectively connected to the oil inlet of the temperature control valve (6) and the oil outlet of the pressure control valve (5) through pipelines.

5. The hydraulic heat dissipation circuit according to claim 4, characterized in that: The flow control valve (4) is a relief throttle valve, comprising a flow regulating hand wheel (4.1) for regulating the output flow rate of the REG priority port (4.3), and the REG priority port (4.3) is also integrated with a safety valve.

6. The hydraulic heat dissipation circuit according to claim 1, characterized in that: The cooling port of the temperature control valve (6) is connected to the oil inlet of the cooling chamber (7.2) through a pipeline; and the bypass port of the temperature control valve (6) is connected to the oil return port of the hydraulic oil tank (3) through a pipeline.

7. The hydraulic heat dissipation circuit according to claim 6, characterized in that: The temperature control valve (6) is a two-position three-way proportional valve, which controls the heat-dissipated hydraulic oil to enter the radiator (7) or return to the hydraulic oil tank (3) by pushing the valve core through the thermal expansion and contraction of the temperature-sensitive material at the end of the valve core.

8. The hydraulic heat dissipation circuit according to claim 1, characterized in that: The pressure control valve (5) is a reverse proportional pilot electromagnetic overflow valve, comprising a main valve (5.2) and a pilot valve (5.1), and the pressure control valve (5) is also integrated with a reverse suction check valve (5.3), which can prevent the hydraulic motor (7.1) from being damaged by suction after the heat dissipation pump (2) stops supplying oil.

9. The hydraulic heat dissipation circuit according to claim 1, characterized in that: The oil outlet of the cooling chamber (7.2) and the oil outlet of the hydraulic motor (7.1) are connected to the oil return port of the hydraulic oil tank (3) through a pipeline after the oil outlet is merged.

10. The hydraulic heat dissipation circuit according to claim 1, characterized in that: The hydraulic oil tank (3) is also provided with an oil suction filter, an oil return filter, a liquid level gauge and an air filter; the oil suction filter can keep the oil entering the hydraulic system clean, the oil return filter can block impurities in the hydraulic system from entering the hydraulic oil tank (3), the liquid level gauge facilitates observation of the liquid level in the hydraulic oil tank (3), and the air filter prevents pollutants in the atmosphere from entering the hydraulic oil tank (3).

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