Pressurizing circulating system of hydraulic retarder

Abstract

The invention belongs to the technical field of vehicle braking, and relates to a hydraulic retarder pressurization circulation system which comprises a retarder working cavity, an oil pool, a heat exchanger, a retarder shaft and an oil seal part, and further comprises a working circulation unit, an idling circulation unit and a control unit. The first supercharging device is arranged to supercharge a working medium, the inlet pressure of the working cavity of the retarder is effectively improved, and the maximum braking torque of the hydraulic retarder and the braking torque performance under the low-rotating-speed working condition are remarkably improved on the premise that the structural size of a stator and a rotor is not increased and the output air pressure of a control valve is not increased; and meanwhile, the pressurized working medium is stably conveyed to the rotor shell channel, the bearing and the oil seal part through the second pressurizing device, it is guaranteed that the lubricating medium of the oil seal is supplied sufficiently, the flow is stable, oil seal abrasion and medium leakage caused by insufficient lubrication are avoided, the service life of the oil seal is prolonged, and the sealing reliability of the oil seal is improved.

Description

Technical Field

[0001] This invention belongs to the field of vehicle braking technology and relates to a hydraulic retarder booster circulation system. Background Technology

[0002] Hydraulic retarders, as key components of vehicle auxiliary braking systems, are widely used in heavy-duty trucks, buses, and new energy commercial vehicles due to their advantages such as no mechanical wear, continuously adjustable braking torque, stable heat dissipation, and fast braking response. Taking the widely used parallel hydraulic retarder as an example, when the retarder starts working, the control valve receives an external control signal and adjusts the pressure of the on-board air source. The pressure-adjusted air source then forces the working medium into the stator and rotor of the retarder's working chamber through the inlet channel. Because the rotor rotates synchronously at high speed with the vehicle's drive shaft, the rotating rotor accelerates and flails the working medium. The accelerated working medium impacts the stator blades at high speed, generating braking torque through the mutual impact between the working medium and the stator and rotor blades, thus converting the kinetic energy generated during vehicle movement into heat energy of the working medium. Subsequently, the heated working medium enters the heat exchanger through the working chamber outlet channel for heat dissipation and cooling. The cooled working medium then re-enters the circulation, repeating this process to achieve a continuous and stable braking effect.

[0003] However, existing parallel hydraulic retarders also have several drawbacks during operation: First, the braking torque of the hydraulic retarder is mainly affected by various factors such as the stator and rotor structural dimensions, system control pressure, and the resistance of the inlet and outlet channels of the working chamber. Due to the strict limitations of the overall vehicle layout space, it is difficult to further increase the outer diameter of the stator and rotor, and the braking torque cannot be increased by expanding the stator and rotor dimensions. Second, the output air pressure of the control valve has an upper limit, making it difficult to break through the bottleneck of braking torque by increasing the system control pressure. This makes it difficult to increase the maximum braking torque of the hydraulic retarder and its maximum braking torque under low speed conditions, and it cannot fully meet the braking needs of the vehicle under complex road conditions. Third, the hydraulic retarder relies on a screw pump to deliver the working medium to the back of the stator in the working chamber of the retarder. Affected by the centrifugal force of the screw pump, the total amount of lubricating medium delivered to the oil seal through the shaft center channel is relatively small and the flow rate fluctuates greatly. The lubrication effect of the oil seal is poor, and problems such as oil seal wear and medium leakage are very likely to occur, which further affects the operational stability and service life of the retarder. Summary of the Invention

[0004] The purpose of this invention is to provide a hydraulic retarder boosting circulation system that can increase the braking torque of a parallel hydraulic retarder, improve the braking torque under low-speed conditions, increase the total amount of lubricating medium delivered to the oil seal, and stabilize the flow rate of the lubricating medium to improve the lubrication effect of the oil seal.

[0005] To achieve the above objectives, the technical solution provided by the present invention is as follows: A hydraulic retarder pressurization and circulation system includes a retarder working chamber, an oil sump, and a heat exchanger. A retarder shaft is disposed within the retarder working chamber, with one end of the shaft passing through the working chamber and sealed to it via an oil seal. The system also includes: The working cycle unit includes a first pressurizing device, the inlet of which is connected to the outlet of the oil sump, the outlet of which is connected to the inlet of the retarder working chamber, the outlet of which is connected to the inlet of the heat exchanger, and the outlet of which is connected to the inlet of the first pressurizing device. The first pressurizing device is used to pressurize the working medium to increase the pressure at the inlet of the retarder working chamber. The idling circulation unit includes a rotor housing channel and a second pressurizing device. The rotor housing channel is located in the working chamber of the retarder and has at least one oil outlet near the oil seal. The inlet of the second pressurizing device is connected to the oil sump outlet, the outlet of the second pressurizing device is connected to one end of the rotor housing channel, and the other end of the rotor housing channel is connected to the inlet of the heat exchanger. The second pressurizing device is used to pressurize the working medium and then deliver it to the oil seal. The control unit is connected to the oil tank, the first booster device, and the second booster device, respectively, and is used to transport the working medium in the oil tank to the first booster device and the second booster device.

[0006] The invention is further characterized by: The retarder rotor is fixedly installed on the side of the retarder shaft near the oil seal, and the retarder stator is fixedly installed on the inner wall of the retarder working chamber. The retarder stator is located on the side of the retarder rotor away from the oil seal. The retarder shaft and the retarder stator are arranged coaxially and pass through the retarder stator. A bearing is provided on the side of the retarder shaft near the retarder stator. The outlet of the second booster device is connected to one end of the lubrication oil inlet channel. The other end of the lubrication oil inlet channel is located in the retarder working chamber and is close to the bearing.

[0007] The oil tank is equipped with a first oil inlet channel. The inlet of the first booster device is connected to the end of the first oil inlet channel through a second oil inlet channel. The outlet of the first booster device is connected to the inlet of the retarder working chamber through a third oil inlet channel. The outlet of the retarder working chamber is connected to the inlet of the heat exchanger through a first oil outlet channel. The outlet of the heat exchanger is connected to one end of the second oil outlet channel. The other end of the second oil outlet channel, the end of the first oil inlet channel, and the end of the second oil inlet channel are interconnected to form a three-way connection structure.

[0008] The second oil inlet channel is equipped with a check valve, and the first oil outlet channel is equipped with a throttling device and a safety valve in sequence.

[0009] The oil tank is equipped with a fourth oil inlet channel. The inlet of the second booster device is connected to the end of the fourth oil inlet channel through the fifth oil inlet channel. The outlet of the second booster device is connected to one end of the rotor housing channel. The other end of the rotor housing channel is connected to one end of the third oil outlet channel. The other end of the third oil outlet channel is connected to the first oil outlet channel at the position between the throttling device and the safety valve.

[0010] The control unit includes: a gas source, which is connected to the upper part of the oil tank through a control valve to provide high-pressure gas to the inside of the oil tank; and a controller, which is electrically connected to the control valve to control the start and stop of the control valve and the valve size.

[0011] The control unit includes: an oil pump, which is located in the first oil inlet channel and is connected to the hydraulic power source through a control valve; and a controller, which is electrically connected to the control valve and is used to control the start and stop of the control valve and the valve size.

[0012] The first and second booster devices are coaxially mounted with the retarder shaft and rotate synchronously with it.

[0013] The hydraulic retarder booster circulation system of the present invention has the following advantages: This invention uses a first pressurizing device to pressurize the working medium, effectively increasing the inlet pressure of the retarder's working chamber. Without increasing the size of the stator and rotor structure or raising the output air pressure of the control valve, it significantly improves the maximum braking torque and braking torque performance of the hydraulic retarder under low-speed conditions, meeting the braking requirements of vehicles in complex road conditions. At the same time, a second pressurizing device stably delivers the pressurized working medium to the rotor housing channel, bearings, and oil seals, ensuring sufficient and stable supply of lubricating medium for the oil seals, avoiding oil seal wear and medium leakage caused by insufficient lubrication, and improving the service life and sealing reliability of the oil seals. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the pneumatic control structure of the present invention.

[0015] Figure 2 This is a schematic diagram of the liquid control structure of the present invention.

[0016] Figure label: 1. Retarder shaft; 2. Retarder stator; 3. Retarder rotor; 4. Rotor housing; 5. Oil seal; 6. Throttling device; 7. Safety valve; 8. Heat exchanger; 9. Oil sump; 10. First pressurizing device; 11. Second pressurizing device; 12. Check valve; 13. Air source; 14. Control valve; 15. Oil pump; 16. First oil inlet channel; 17. Second oil inlet channel; 18. Third oil inlet channel; 19. First oil outlet channel; 20. Second oil outlet channel; 21. Fourth oil inlet channel; 22. Fifth oil inlet channel; 23. Sixth oil inlet channel; 24. Third oil outlet channel; 25. Rotor housing channel; 26. Rotor housing inlet; 27. Rotor housing outlet; 28. Controller; 29. ​​Lubrication oil inlet channel. Detailed Implementation

[0017] The technical solutions of the present invention will now be described clearly and in detail with reference to the accompanying drawings. In the description of the embodiments of the present invention, unless otherwise stated, " / " indicates "or," for example, A / B can mean A or B. "And / or" in the text is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A alone, A and B simultaneously, and B alone. Furthermore, in the description of the embodiments of the present invention, "multiple" refers to two or more. The terms "first" and "second" are used for descriptive purposes only and should not be construed as implying or suggesting relative importance or implicitly indicating the number of indicated technical features. Therefore, a feature defined with "first" or "second" may explicitly or implicitly include one or more of that feature.

[0018] like Figure 1 , Figure 2As shown, this invention provides a hydraulic retarder pressurization and circulation system, including a retarder working chamber, an oil tank 9, and a heat exchanger 8. A retarder shaft 1 is disposed within the retarder working chamber. The oil tank 9 stores a working medium. One end of the retarder shaft 1 passes through the retarder working chamber and is sealed to it via an oil seal 5. The system also includes a working circulation unit, an idle circulation unit, and a control unit. The working circulation unit includes a first pressurization device 10. The inlet of the first pressurization device 10 is connected to the outlet of the oil tank 9, the outlet of the first pressurization device 10 is connected to the inlet of the retarder working chamber, the outlet of the retarder working chamber is connected to the inlet of the heat exchanger 8, and the outlet of the heat exchanger 8 is connected to the inlet of the first pressurization device 10. The first pressurization device 10 is used to pressurize the working medium. The retarder working chamber inlet pressure is increased by pressurization. The idling circulation unit includes a rotor housing channel 25 and a second pressurization device 11. The rotor housing channel 25 is located in the retarder working chamber and has at least one oil outlet near the oil seal 5. The inlet of the second pressurization device 11 is connected to the outlet of the oil sump 9, and the outlet of the second pressurization device 11 is connected to one end of the rotor housing channel 25. The other end of the rotor housing channel 25 is connected to the inlet of the heat exchanger 8. The second pressurization device 11 is used to pressurize the working medium and then deliver it to the oil seal 5. The control unit is connected to the oil sump 9, the first pressurization device 10, and the second pressurization device 11 respectively, and is used to deliver the working medium in the oil sump 9 to the first pressurization device 10 and the second pressurization device 11.

[0019] like Figure 1 , Figure 2 As shown, a retarder rotor 3 is fixedly installed on the side of the retarder shaft 1 near the oil seal 5. A retarder stator 2 is fixedly installed on the inner wall of the retarder working chamber. The retarder stator 2 is located on the side of the retarder rotor 3 away from the oil seal 5. The retarder shaft 1 and the retarder stator 2 are arranged coaxially and pass through the retarder stator 2. A bearing is provided on the side of the retarder shaft 1 near the retarder stator 2. The outlet of the second pressurizing device 11 is connected to one end of the lubrication oil inlet channel 29. The other end of the lubrication oil inlet channel 29 is located in the retarder working chamber and is close to the bearing. The second pressurizing device directly delivers lubricating medium to the bearing in the retarder working chamber through the lubrication oil inlet channel 29 to ensure sufficient and stable lubrication of the bearing and improve the operating stability and service life of the retarder.

[0020] like Figure 1 , Figure 2 As shown, the retarder working chamber is constructed from a stator housing and a rotor housing 4. The stator housing and the rotor housing 4 are interlocked and sealed together. The retarder stator 2 is fixed on the inner wall of the stator housing. The retarder rotor 3 is located inside the rotor housing 4. The upper part of the rotor housing 4 is provided with a rotor housing inlet 26, and the lower part of the rotor housing 4 is provided with a rotor housing outlet 27. The rotor housing channel 25 is located inside the rotor housing 4 and its two ends are connected to the rotor housing inlet 26 and the rotor housing outlet 27, respectively.

[0021] like Figure 1 , Figure 2 As shown, the oil tank 9 is provided with a first oil inlet channel 16. The inlet of the first booster device 10 is connected to the end of the first oil inlet channel 16 through a second oil inlet channel 17. The outlet of the first booster device 10 is connected to the inlet of the retarder working chamber through a third oil inlet channel 18. The outlet of the retarder working chamber is connected to the inlet of the heat exchanger 8 through a first oil outlet channel 19. The outlet of the heat exchanger 8 is connected to one end of the second oil outlet channel 20. The other end of the second oil outlet channel 20, the end of the first oil inlet channel 16, and the end of the second oil inlet channel 17 are interconnected to form a three-way connection structure.

[0022] like Figure 1 , Figure 2 As shown, a one-way valve 12 is installed on the second oil inlet channel 17. The one-way valve 12 is used to prevent the working medium from flowing back in the oil circuit, ensuring that the working medium can only flow into the retarder working chamber in the set direction, maintaining stable oil circuit pressure, and avoiding backflow from impacting the booster device. A throttling device 6 and a safety valve 7 are installed in sequence on the first oil outlet channel 19. The throttling device 6 throttles and limits the flow of the medium flowing out of the retarder working chamber, controls the circuit flow and oil pressure, ensures stable medium pressure in the retarder working chamber, and makes the braking torque output smooth and adjustable. The safety valve 7 can be opened to release pressure when the system pressure exceeds the set value, preventing the oil circuit pressure from being too high and damaging the pipeline, valves and booster device, playing an overpressure protection role and improving system safety.

[0023] like Figure 1 , Figure 2 As shown, the oil tank 9 is provided with a fourth oil inlet channel 21. The inlet of the second booster device 11 is connected to the end of the fourth oil inlet channel 21 through the fifth oil inlet channel 22. The outlet of the second booster device 11 is connected to one end of the rotor housing channel 25. The other end of the rotor housing channel 25 is connected to one end of the third oil outlet channel 24. The other end of the third oil outlet channel 24 is connected to the first oil outlet channel 19 at the position between the throttling device 6 and the safety valve 7.

[0024] like Figure 1 As shown, the control unit includes an air source 13, a control valve 14, and a controller 28. The air source 13 is connected to the upper part of the oil tank 9 through the control valve 14. The air source 13 is used to provide high-pressure gas to the inside of the oil tank 9. The controller 28 is electrically connected to the control valve 14. The controller 28 is used to control the start and stop of the control valve 14 and the valve size.

[0025] like Figure 2As shown, the control unit includes an oil pump 15, a control valve 14, and a controller 28. The oil pump 15 is installed on the first oil inlet channel 16. The oil pump 15 is connected to the hydraulic power source through the control valve 14. The controller 28 is electrically connected to the control valve 14 and is used to control the start and stop of the control valve 14 and the valve size.

[0026] like Figure 1 , Figure 2 As shown, the first booster device 10 and the second booster device 11 are coaxially arranged with the retarder shaft 1 and rotate synchronously with the retarder shaft 1. The coaxial integrated drive structure enables the first booster device 10 and the second booster device 11 to rotate synchronously with the retarder shaft 1. The power of the retarder shaft 1 is directly utilized for drive, eliminating the need for an additional independent power source. This significantly improves the power response speed and transmission efficiency, while greatly simplifying the system structure layout and reducing the overall installation space.

[0027] Working principle: When the hydraulic retarder is in operation, after receiving the control signal from the controller 28, the control valve 14 fills the space above the oil sump 9 with high-pressure gas supplied by the gas source 13. The one-way valve 12 opens at a relatively low pressure. Under the action of gas pressure, the working medium flows through the first oil inlet channel 16 and the second oil inlet channel 17 in sequence into the first pressurizing device 10. The first pressurizing device 10 rotates synchronously with the retarder shaft 1. Under the work of the impeller, the mechanical energy is converted into the pressure energy of the working medium. The pressurized working medium enters the working chamber of the retarder through the third oil inlet channel 18 to achieve slow braking.

[0028] Due to the increased inlet pressure of the retarder's working chamber, the outlet pressure of the working chamber increases accordingly for the same stator 2 and rotor 3. The heated and pressurized working medium enters the heat exchanger 8 through the first oil outlet channel 19 and the throttling device 6. After cooling in the heat exchanger 8, it flows back to the oil sump 9. The control pressure above the oil sump 9 remains constant, increasing the pressure difference at the working chamber outlet channel and increasing the working medium flow rate. After the system reaches steady-state equilibrium, the flow rate and pressure of the working cycle increase simultaneously, ultimately increasing the braking torque. The vehicle can adapt the cooling medium flow rate and heat dissipation power according to the braking power requirements to prevent the retarder from overheating.

[0029] During the idling operation of the hydraulic retarder, the pressure above the oil sump 9 is atmospheric, and the main circuit check valve 12 is closed. Under the action of the second pressurizing device 11, the working medium in the oil sump 9 is drawn into the second pressurizing device 11 through the fourth oil inlet channel 21 and the fifth oil inlet channel 22. The second pressurizing device 11 rotates synchronously with the retarder shaft 1, converting mechanical energy into pressure energy of the working medium under the work of the impeller. The pressurized working medium enters the rotor housing channel 25 through the sixth oil inlet channel 23 and flows from top to bottom in the rotor housing 4. When it flows through the position where the rotor housing 4 and the retarder shaft 1 meet, part or all of the working medium flows out to lubricate the oil seal 5. Then, under the centrifugal force of the retarder rotor 3, it flows out of the retarder working chamber and flows into the heat exchanger 8 through the first oil outlet channel 19. The working medium that does not participate in lubrication flows into the heat exchanger 8 through the third oil outlet channel 24, completing the idling cycle. The system continues to circulate.

[0030] The hydraulic retarder booster circulation system of the present invention has the following other advantages: First, the present invention sets a first pressurization device in the working cycle of the retarder. Through reasonable structural design, it can offset the reduction in oil inlet pressure of the retarder working chamber caused by the resistance of the device itself and the resistance of the working chamber inlet, thereby achieving a significant increase in braking torque under the existing stator and rotor structure.

[0031] Secondly, due to the addition of the first booster device, the outer diameter of the stator and rotor circulation circle can be reduced while keeping the design braking torque unchanged, and the radial dimension of the retarder working chamber can be reduced, making it possible to match the retarder with different gearboxes.

[0032] Third, by introducing a second booster device and a forced lubrication circuit into the idling cycle, the present invention can achieve forced lubrication of the oil seal and reduce the occurrence of oil leakage faults in the retarder.

[0033] It is understood that this invention has been described through some embodiments, and those skilled in the art will recognize that various changes or equivalent substitutions can be made to these features and embodiments without departing from the spirit and scope of this invention. Furthermore, under the teachings of this invention, these features and embodiments can be modified to adapt to specific situations and materials without departing from the spirit and scope of this invention. Therefore, this invention is not limited to the specific embodiments disclosed herein, and all embodiments falling within the scope of the claims of this invention are within the protection scope of this invention.

Claims

1. A hydraulic retarder pressurization and circulation system, comprising a retarder working chamber, an oil sump, and a heat exchanger, wherein a retarder shaft is disposed within the retarder working chamber, one end of the retarder shaft passing through the retarder working chamber and being sealed to the retarder working chamber via an oil seal, characterized in that, Also includes: The working cycle unit includes a first pressurizing device, the inlet of which is connected to the outlet of the oil sump, the outlet of which is connected to the inlet of the retarder working chamber, the outlet of which is connected to the inlet of the heat exchanger, and the outlet of which is connected to the inlet of the first pressurizing device. The first pressurizing device is used to pressurize the working medium to increase the pressure at the inlet of the retarder working chamber. The idling circulation unit includes a rotor housing channel and a second pressurizing device. The rotor housing channel is located in the working chamber of the retarder and has at least one oil outlet near the oil seal. The inlet of the second pressurizing device is connected to the oil sump outlet, and the outlet of the second pressurizing device is connected to one end of the rotor housing channel. The other end of the rotor housing channel is connected to the inlet of the heat exchanger. The second pressurizing device is used to pressurize the working medium and then deliver it to the oil seal. The control unit is connected to the oil tank, the first booster device, and the second booster device, respectively, and is used to transport the working medium in the oil tank to the first booster device and the second booster device.

2. The hydraulic retarder booster circulation system according to claim 1, characterized in that, A retarder rotor is fixedly mounted on the retarder shaft near the oil seal. A retarder stator is fixedly mounted on the inner wall of the retarder working chamber. The retarder stator is located on the side of the retarder rotor away from the oil seal. The retarder shaft is coaxially arranged with the retarder stator and passes through the retarder stator. A bearing is provided on the retarder shaft near the retarder stator. One end of the outlet of the second booster device is connected to a lubrication oil inlet channel. The other end of the lubrication oil inlet channel is located inside the retarder working chamber and is close to the bearing.

3. The hydraulic retarder booster circulation system according to claim 1, characterized in that, The oil tank is provided with a first oil inlet channel. The inlet of the first booster device is connected to the end of the first oil inlet channel through a second oil inlet channel. The outlet of the first booster device is connected to the inlet of the retarder working chamber through a third oil inlet channel. The outlet of the retarder working chamber is connected to the inlet of the heat exchanger through a first oil outlet channel. The outlet of the heat exchanger is connected to one end of the second oil outlet channel. The other end of the second oil outlet channel, the end of the first oil inlet channel, and the end of the second oil inlet channel are interconnected to form a three-way connection structure.

4. The hydraulic retarder booster circulation system according to claim 3, characterized in that, The second oil inlet channel is equipped with a check valve, and the first oil outlet channel is equipped with a throttling device and a safety valve in sequence.

5. The hydraulic retarder booster circulation system according to claim 4, characterized in that, The oil tank is provided with a fourth oil inlet channel. The inlet of the second booster device is connected to the end of the fourth oil inlet channel through a fifth oil inlet channel. The outlet of the second booster device is connected to one end of the rotor housing channel. The other end of the rotor housing channel is connected to one end of the third oil outlet channel. The other end of the third oil outlet channel is connected to the first oil outlet channel at the position between the throttling device and the safety valve.

6. The hydraulic retarder booster circulation system according to claim 3, characterized in that, The control unit includes: a gas source, which is connected to the upper part of the oil tank through a control valve, for providing high-pressure gas to the inside of the oil tank; and a controller, which is electrically connected to the control valve, for controlling the start and stop of the control valve and the valve size.

7. The hydraulic retarder booster circulation system according to claim 3, characterized in that, The control unit includes: an oil pump, which is installed in the first oil inlet channel and is connected to a hydraulic power source through a control valve; and a controller, which is electrically connected to the control valve and is used to control the start and stop of the control valve and the valve size.

8. The hydraulic retarder booster circulation system according to claim 3, characterized in that, The first and second booster devices are coaxially arranged with the retarder shaft and rotate synchronously with the retarder shaft.

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