WO2021164090A1

WO2021164090A1 - Pump-type magnetorheological fluid retarder

Info

Publication number: WO2021164090A1
Application number: PCT/CN2020/080368
Authority: WO
Inventors: 任孝义; 王文辉; 陈永祥; 沈栋平; 高凤才; 刘佳铭; 郑璐
Original assignee: 富奥汽车零部件股份有限公司
Priority date: 2020-02-22
Filing date: 2020-03-20
Publication date: 2021-08-26
Also published as: CN111043186A; CN111043186B

Abstract

A pump-type magnetorheological fluid retarder. A retarder shaft (2) and a pump form a torque resistant-type drive connection; a steel plate (12) is mounted within a retarder body (3) and separates the retarder body (3) into a left side high/low pressure area through channel and a right side working cavity; a magnetizable material silicon steel plate (20) and a working magnetism coil (14) are mounted on the working cavity side; the pump is mounted within the right side working cavity where the retarder body (3) and the steel plate (12) are separated; the working cavity and the high/low pressure area through channel are filled with a working medium magnetorheological fluid; a magnetorheological fluid valve (17) is arranged within a left side through channel of a high pressure area steel plate hole of the steel plate (12). Within a working temperature range, the viscosity of the magnetorheological fluid under the action of a magnetic field is less affected by temperature, and is proportional to the strength of the magnetic field, having superior controllability, where a greatest braking force is controllable and can be far greater than common hydraulic retarders, the braking force is steady, the same braking force can also be produced at low rotational speeds, and necessary speed retarding braking force can be produced at any vehicular speed, not only for use on long declines of mountainous roads, but also having broad use in cities for vehicles requiring frequent deceleration; the present invention can replace main braking to implement braking, and greatly reduces the use frequency of a main braking device.

Description

Pump type magnetorheological fluid retarder

Technical field

The invention belongs to the technical field of vehicle retarders, and relates to a pump-type magnetorheological fluid retarder; it is particularly suitable for various vehicles, cars, trucks, bus engineering vehicles and the like.

Background technique

Due to the large number of urban road intersections, dense bus stops, and large passenger flow, buses often brake frequently; mountain roads are steep and have many sharp bends, and medium and large trucks and buses that travel on mountain roads for a long time often need to brake.

When the brakes work frequently for a long time, they will cause rapid wear of the brake shoes, short service life of the brake friction linings, loss of braking force or significant reduction of braking performance due to thermal degradation of the brakes, which has also become the main cause of traffic accidents. Therefore, it is necessary to be equipped with an auxiliary braking system.

As an auxiliary braking component of the vehicle, the retarder reduces the load of the original vehicle's braking system by acting on the original vehicle's transmission system, so that the vehicle decelerates evenly, so as to improve the reliability of the vehicle's braking system and extend the use of the braking system Longevity, and can therefore greatly reduce the cost of vehicle use.

Usually retarders include engine retarders, exhaust brakes, eddy current retarders, hydraulic retarders, and magnetorheological disc retarders. Some low-speed braking power is very small, some consume a lot of power, some are heavy, and some are very small.

Ordinary hydraulic retarders have stators and rotors, and need to increase or decrease the medium and oil storage in the working chamber, which makes the structure complicated.

The existing magnetorheological fluid brakes and retarders all use the magnetorheological fluid in a certain strength of the magnetic field to increase the viscosity and use the shear or squeeze force to generate resistance. The braking force is limited; the area of the ordinary magnetorheological fluid retarder brake disc is small, the magnetorheological fluid does not circulate and the heat exchange efficiency is low; there is wear, the torque is limited by the size, and the performance of the magnetorheological fluid The requirements are higher, the cost is high, the size is large, etc., and it cannot be used in batches in vehicles.

Summary of the invention

The invention discloses a pump type magnetorheological fluid retarder to solve the complex structure of the stator and rotor hydraulic retarder in the prior art; the prior art magnetorheological fluid brake and retarder produce limited braking force , The torque is limited by size and other issues.

The invention includes input gear, retarder shaft, retarder body, steel plate, O-ring seal, end cover, working magnetic coil, silicon steel plate, magnetorheological fluid valve, pump; no stator is required; retarder shaft and Pump torsion-resistant drive connection; steel plate is installed in the retarder body, separating the retarder body from the left high and low pressure zone channel F and the right working cavity E; the magnetizable material silicon steel plate and the working magnetic coil are installed in the working cavity E side; the pump is installed in the working chamber E on the right side separated from the retarder body and the steel plate; the working chamber E and the high and low pressure zone channel F are filled with the working medium magnetorheological fluid, and ensure that there is no air; the steel plate is facing the rotor height There are round holes in the low-pressure zone; the magnetorheological fluid valve is arranged in the left channel F of the steel plate hole in the high-pressure zone of the steel plate and fixed on the steel plate; when the working magnetic coil is not energized, the channel F in the high and low pressure zone is connected to the working chamber E and the pump The high-pressure area and the low-pressure area are directly connected, no pressure difference is generated, and no braking; the pump working element rotates in the magnetorheological fluid with very low viscosity and lubricates itself; when the excitation coil is loaded with current, under the action of the magnetic field, the working chamber E The viscosity of the magnetorheological fluid inside the medium increases rapidly, and the magnetorheological fluid with high viscosity cannot pass through the magnetorheological fluid valve. The channel F in the high and low pressure zone is closed, and the high and low pressure zone of the working chamber E instantly generates a high and low pressure difference, forming braking resistance; Load current on the working excitation coil as required to generate magnetic fields of different strengths, adjust the viscosity of the magnetorheological fluid, control the viscosity of the magnetorheological fluid in the working chamber E, generate different back pressures, and generate different braking forces.

An optimized solution is that the magnetorheological fluid valve includes an excitation coil and silicon steel plate; the excitation coil core iron is a hollow structure; the excitation coil is placed on the circular hole of the steel plate facing the low-voltage area, within the range corresponding to the hollow hole of the excitation coil core iron. The steel plate has multiple small holes, or high-strength steel mesh; constitutes a magnetorheological fluid valve that controls the on and off of channel F; when the excitation coil is energized, the porous structure makes the high-viscosity magnetorheological fluid block the small holes and cannot flow back. The passage in the low-pressure area is cut off, so that the pressure difference in the high-low pressure area is generated, and the braking force is generated. When the required braking force is very small, the current of the excitation coil can be adjusted at the same time to allow a small amount of magnetorheological fluid to pass through the high and low pressure areas to reduce the braking resistance; when the brake is released, the excitation coil current is zero; the no-load separation is achieved; Load loss and realize the lubrication of the rotor.

Another optimized solution, the magnetorheological fluid valve includes a one-way valve plate, ejector rod, sealing ring, piston, oil seal, and return spring; the oil seal forms a closed cavity with the body and the piston cylinder, and the right side of the piston is at the ejector rod. , One end of the return spring acts on the shell, and the other end acts on the one-way valve; the high-pressure port of the steel plate faces the oil outlet or the return port in the low-pressure zone; the one-way valve opens when the magnetorheological fluid has the maximum viscosity State; when compressed air or hydraulic oil is passed, push the piston to the left to close the valve plate and close the passage in the high and low pressure zone of the rotor to generate braking force.

When the pump is a rotor pump or gear pump, the end cover has a magnetizable material silicon steel plate mounting cavity, and the working magnetic coil, core iron and silicon steel plate are packaged and installed in the mounting cavity of the end cover; when the pump is a spiral rotor pump When the rotor is directly matched with the housing; the working magnetic coil is arranged on the outer circle of the rotor or on the left side of the rotor; the rotor can be a set of inner rotor and outer rotor installed in the body; the rotor or gear can be cascaded in series Structure: When the axial size of the cascade series is too large, an additional excitation coil can be arranged in the working cavity at the left end at the same time.

The spiral rotor pump can be single-shaft, double-shaft, or three-shaft type. When the spiral rotor pump is used, the excitation coil and the excitation coil are all arranged on the outer circle.

The invention is arranged after the gearbox and is arranged in parallel or in series with the output shaft of the gearbox; whether in parallel or in series, the retarder shaft keeps rotating when the vehicle is running; when arranged in parallel, the retarder shaft and the input gear are connected in a torsion-resistant manner ; The input gear meshes with the gearbox gear for transmission; when arranged in series, the front end of the retarder shaft is connected to the gearbox output shaft through a flange, and the output is connected with the transmission shaft; the retarder shaft keeps rotating when the vehicle is running; working cavity The input and output ports of E are respectively connected to the inlet and outlet of the heat exchanger; the low pressure port is the oil return port, which directly communicates with the oil outlet of the heat exchanger; the rotor, shell and heat exchanger form a closed cavity; when working, There is no magnetic field in the heat exchanger; the magnetorheological fluid circulates and exchanges heat with low viscosity in the heat exchanger and exchanges heat to the coolant. The heat exchanger can be arranged behind the pump or outside the shell; cooling water channels can be arranged on the shell at the same time to increase the cooling effect; the outlet of the heat exchanger adopts small orifice steel plate throttling; the inlet adopts Large-caliber reflux; oil plugs are installed on the upper side of the working chamber E of the retarder body; oil drain plugs are installed on the lower side of the passage F in the high and low pressure zone; there is no need to press in or remove the medium in the working chamber E.

The working temperature of the present invention is generally -40°C to 160°C; the inlet and outlet are respectively arranged with an inlet temperature sensor and an outlet temperature sensor to measure the temperature of the inlet and outlet. Magnetorheological fluid viscosity output and back pressure can reach up to 3 to 4 MPa, and can be higher according to needs; the low pressure port is the oil return port, which directly communicates with the oil outlet of the heat exchanger; the heat exchanger withstands pressure at least 4 MPa; magnetic flow The maximum braking torque of the variable fluid can reach 10000Nm, and the power consumption is small; the high temperature and low speed braking force in the operating temperature range is much higher than other ordinary retarders, so the braking force is affected by the speed and the temperature is less affected by the temperature. .

The invention can match various format heat exchangers and drum heat exchangers made of aluminum alloy materials.

The positive effect of the present invention is that the viscosity of the magnetorheological fluid under the action of the magnetic field in the working temperature range is less affected by temperature, is proportional to the strength of the magnetic field, has excellent controllability, and the maximum braking force is controllable and can be much larger than usual Hydraulic retarder with stable braking force and low speed can also produce the same braking force. It can basically generate the required retarding braking force at any vehicle speed. It is not only used for long slopes on mountain roads, but also can be widely used in cities. Frequent speed reduction requirements of the car; even according to requirements, it can be used occasionally instead of the main brake to implement braking, which can greatly reduce the frequency of use of the main brake. Small size, light weight, low power consumption, high power, good heat dissipation, and convenient layout. The rotor and the inside of the shell and the heat exchanger form a closed cavity, with only the oil filling hole that can be exhausted, and the oil discharge port for replacing the medium underneath. Therefore, the amount of magnetorheological fluid medium is reduced, and the structure is greatly simplified; the amount of magnetorheological fluid is small, so the cost is within a controllable range.

Description of the drawings

Fig. 1 is a schematic diagram of the structure of the inner meshing cycloid rotor pump type magnetorheological fluid retarder according to the first embodiment of the invention;

2 is a cross-sectional view A-A of the first embodiment of the invention;

Figure 3 is a B-B cross-sectional view of the first embodiment of the invention;

Figure 4 is a C-C cross-sectional view of the first embodiment of the invention;

5 is a schematic diagram of the structure of an internal meshing cycloid rotor pump type magnetorheological fluid retarder that uses a mechanical way to switch on and off the channel F according to the second embodiment of the invention;

6 is a schematic diagram of the internal meshing involute or cycloid gear pump type magnetorheological fluid retarder with the excitation coil arranged at the low pressure return port of the steel plate according to the third embodiment of the invention;

In the picture: 1 input gear, 2 retarder shaft, 3 retarder body, 4 front bearing, 5 shaft right end rear bearing, 6 outer oil seal, 7 outer oil seal, 8 inner oil seal, 9 inner oil seal, 10 inner rotor, 11 Outer rotor, 12 steel plate, 13 right end cover, 14 working magnetic coil, 15 inlet temperature sensor, 16 outlet temperature sensor, 17 excitation coil, 18 steel plate, 19-1 check valve plate, 19-2 ejector rod, 19-3 return Position spring, 19-4 sealing ring, 19-5 piston, 19-6 oil seal, 20 silicon steel plate, 21 oil filler plug, 22 oil drain plug, 23 exhaust check valve, E working chamber, F high and low pressure zone channel .

Detailed ways

The embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

The first embodiment of the present invention is an internal meshing cycloid rotor pump type magnetorheological fluid retarder; as shown in Figure 1, Figure 2, Figure 3, Figure 4, the parallel arrangement with input gear and through the spline and retarder Torsion-resistant connection of the shaft; including input gear 1, retarder shaft 2, retarder body 3, front bearing 4, rear bearing at the right end of the shaft 5, outer oil seal 6, outer oil seal 7, inner oil seal 8, inner oil seal 9, Pump, steel plate 12, right end cover 13, working magnetic coil 14, inlet temperature sensor 15, outlet temperature sensor 16, excitation coil 17,

steel plate

18, 20 silicon steel plate, 21 oil filler plug, 22 oil drain plug, 23 exhaust gas sheet Direction valve, E working cavity, F high and low pressure zone channel; the body 3 has an inner rotor 10 and an eccentric outer rotor 11; the left side of the end cover 13 and the right side of the silicon steel sheet 20 are arranged with a working magnetic coil 14; working magnetic coil The 14-core iron and the silicon steel sheet 20 are packaged together. The retarder body 3 is separated from the steel plate 12, the silicon steel sheet 20 and the end cover 13 to form a working cavity E; the left side of the steel plate 12 and the right end of the body 3 form a high and low pressure zone channel F; The channel F in the high and low pressure zone is filled with magnetorheological fluid and is guaranteed to be free of air; the retarder uses the magnetorheological fluid with adjustable viscosity as the working medium; the retarder shaft 2 is connected to the inner rotor of the retarder in a torsion-resistant manner, Drive the inner rotor to rotate; the magnetorheological fluid valve structure is arranged on the channel in the high and low pressure zone to control the on and off of the channel F; the working magnetic coil 14 can be arranged axially on the outer edge of the rotor and embedded in the retarder body 3; also It can be arranged at both ends, sealed on the end cover 13 or the left side of the body 3 by a steel plate; the right end of the core iron with an inner hole of the excitation coil 17 is fixed to the steel plate 12, and the end face is sealed, and the inner hole is with the high pressure zone hole of the steel plate 12 The excitation steel plate 18 is fixed at the left end of the coil 17 and the end face is sealed, or the outer edge of the steel plate 18 is seated on the wall of the channel F in order to increase the force capacity; the area of the steel plate 18 opposite to the inner hole of the coil core iron is not full of one or more small Hole directly communicates with channel F; when the coil is not energized, the channel F in the high and low pressure zone directly communicates with the working chamber E, the rotor high pressure zone and the low pressure zone through the steel plate 12, the core iron inner hole of the coil 17, and the multiple small holes of the steel plate 18 , No pressure difference is generated, no braking, the rotor rotates in the magnetorheological fluid with very low viscosity, and lubricates itself; when the excitation coil 17 is loaded with current, under the action of the magnetic field, the magnetorheological medium in the core of the coil 17 The viscosity of the fluid increases rapidly, and the high-viscosity magnetorheological fluid cannot flow through the small holes of the steel plate 18 to the channel F of the high and low pressure zone, and flow back to the low pressure zone of the working chamber E; the channel F of the high and low pressure zone is closed, and the high and low pressure zone of the working chamber E is generated instantaneously The high and low pressure difference forms braking resistance; by loading current on the working excitation coil 14, the viscosity of the magnetorheological fluid is adjusted and changed, thereby generating different braking forces; when the required braking force is very small, the current of the excitation coil 17 can be adjusted at the same time , To allow a small amount of magnetorheological fluid to pass through the high and low pressure areas to reduce braking resistance; when the brake is released, the current of the working excitation coil 14, the excitation coil 17 is zero, and the brake is released; the rotor is realized by the principle of magnetorheological fluid valve viscosity change The on-off of the high and low pressure zone is equivalent to increasing the gap between the rotor and the shell, and the height cannot be established. The pressure difference in the nip can realize no-load separation and realize no-load separation; reduce no-load loss and realize the lubrication of the rotor.

The second embodiment of the present invention is an internal meshing cycloid rotor pump type magnetorheological fluid retarder that uses a mechanical way to switch on and off the channel F, as shown in Figure 5: the high-pressure port of the steel plate 12 faces the oil outlet, and the oil is discharged On the left side of the port, install the one-way valve plate 19-1, the ejector rod 19-2, and the return spring 19-3; the lower part of the return spring 19-3 acts on the housing, and the upper part acts on the one-way valve plate 19-1, Ensure that the one-way valve 19-1 can be opened at the maximum viscosity of the magnetorheological fluid; the sealing ring 19-4 and the right side of the piston 19-5 have an oil seal 19-6 at the mandrel to form a seal with the body piston cylinder Cavity; when compressed air or hydraulic oil is passed, the piston 19-5 is pushed to the left to close the valve plate and close the passage of the rotor high and low pressure area formed by the B cavity to generate braking force. The third embodiment of the present invention is an internal meshing involute gear or internal meshing cycloid rotor pump type magnetorheological fluid retarder. The magnetorheological fluid valve of the on-off channel F is arranged at the return port of the low pressure zone of the steel plate 12 As shown in Figure 2, Figure 3, Figure 4, Figure 6: the excitation coil 17 is placed on the left side of the circular hole of the steel plate 12 facing the low-voltage zone, and fixed, and the end surface is sealed; the return hole porous structure, when the excitation coil is added During electricity, the high-viscosity magnetorheological fluid cannot flow back, and the passage in the high and low pressure area is cut off, so that the pressure difference in the high and low pressure area is generated, and the braking force is generated; this magnetorheological fluid valve structure can be arranged in the middle of the passage in the high and low pressure area. Any position, as long as the channel in the high and low pressure area can be switched on and off.

The present invention is not limited to the exemplified structure of the embodiment. The retarder can not only adopt an internal meshing rotor, but also an external meshing rotor, a one-shaft screw pump rotor, a two-shaft spiral rotor magnetorheological fluid retarder, and a three-shaft spiral. Type rotor magnetorheological fluid retarder, etc. all fall into the protection scope of the present invention.

Claims

A pump type magnetorheological fluid retarder; it is characterized in that it comprises a retarder shaft, a retarder body, a steel plate, an O-ring seal, an end cover, a working magnetic coil, a silicon steel plate, a magnetorheological fluid valve, Pump; does not require a stator; the retarder shaft is connected with the pump torsion-resistant drive; the steel plate is installed in the retarder body, separating the retarder body from the left high and low pressure zone channel and the right working cavity; magnetizable material silicon steel The plate and the working magnetic coil are installed on the side of the working chamber; the pump is installed in the working chamber on the right side separated from the retarder body and the steel plate; the working chamber and the high and low pressure zone channels are filled with the working medium magnetorheological fluid, and it is guaranteed to be free of air; steel plate There are circular holes directly opposite the high and low pressure zone of the rotor; the magnetorheological fluid valve is arranged in the left channel of the steel plate hole in the steel plate high pressure zone; when the working magnetic coil is not energized, the high and low pressure zone channel and the working chamber, the pump high pressure zone and the low pressure The area is directly connected, no pressure difference is generated, and cannot be braked; the pump working element rotates in the magnetorheological fluid with very low viscosity and lubricates itself; when the excitation coil is loaded with current, under the action of the magnetic field, the magnetic flow of the medium in the working chamber The viscosity of the variable fluid increases rapidly, and the high-viscosity magnetorheological fluid cannot pass through the magnetorheological fluid valve. The channel in the high and low pressure zone is closed. The high and low pressure zone of the working chamber instantly generates a high and low pressure difference to form a braking resistance; on the working excitation coil as required Load current to generate magnetic fields of different strengths to adjust the viscosity of the magnetorheological fluid, control the viscosity of the magnetorheological fluid in the working chamber, generate different back pressures, and generate different braking forces.
The pump-type magnetorheological fluid retarder according to claim 1, wherein the magnetorheological fluid valve includes an excitation coil and a silicon steel plate; the excitation coil core iron is a hollow structure; the excitation coil is placed against the steel plate At the round hole in the low-voltage area, the steel plate has multiple small holes or high-strength steel mesh within the range corresponding to the hollow hole of the excitation coil core iron; it constitutes a magnetorheological fluid valve that controls the on and off of the channel; when the excitation coil is energized, The porous structure makes the high-viscosity magnetorheological fluid block the small pores and cannot flow back, and the passage in the high and low pressure zone is cut off, so that the pressure difference in the high and low pressure zone is generated, and the braking force is generated.
A pump-type magnetorheological fluid retarder according to claim 2; characterized in that: when the required braking force is very small, the current of the excitation coil can be adjusted at the same time, so that a small amount of magnetorheological fluid can pass through the high and low pressure areas, reducing Braking resistance; when the brake is released, the excitation coil current is zero; the no-load separation is realized; the no-load loss is reduced and the rotor is lubricated.
A pump-type magnetorheological fluid retarder according to claim 1, characterized in that: the magnetorheological fluid valve includes a one-way valve plate, an ejector rod, a sealing ring, a piston, an oil seal, and a return spring; an oil seal and The body and the piston cylinder form a closed cavity. The right side of the piston is at the top rod. One end of the return spring acts on the shell and the other end acts on the one-way valve; the high pressure port of the steel plate faces the oil outlet or flows back in the low pressure area. Port; when the magnetorheological fluid has the maximum viscosity, the one-way valve is in an open state; when compressed air or hydraulic oil is passed, the piston is pushed to the left to close the valve, and the passage in the high and low pressure zone of the rotor is closed, resulting in a brake power.
The pump-type magnetorheological fluid retarder according to claim 1, wherein when the pump is a rotor pump or a gear pump, the end cover has a magnetizable material silicon steel plate mounting cavity, and the working magnetic coil and core The iron and silicon steel plate are packaged and installed in the installation cavity of the end cover; when the pump is a spiral rotor pump; the rotor is directly matched with the shell; the working magnetic coil is arranged on the outer circle of the rotor, or it can be arranged on the left side of the rotor; the rotor A set of inner rotor and outer rotor installed in the body can be used; the rotor or gear can adopt a cascade series structure; when the axial size of the cascade series is too large, an additional excitation coil can be arranged in the left working cavity at the same time.
The pump-type magnetorheological fluid retarder according to claim 1, characterized in that: the spiral rotor pump can be a single-shaft, or double-shaft, or three-shaft type; when the spiral rotor pump is used, the excitation coil and the excitation The coils are all arranged on the outer circle.
The pump-type magnetorheological fluid retarder according to claim 1, characterized in that: it is arranged behind the gearbox and arranged in parallel or in series with the output shaft of the gearbox; when arranged in parallel, the retarder shaft and the input gear Torsion-resistant connection; the input gear meshes with the gearbox gear for transmission; when arranged in series, the front end of the retarder shaft is connected with the gearbox output shaft through a flange, and the output is connected with the transmission shaft in a normal way; the retarder shaft is maintained when the vehicle is running Rotation; the input and output ports of the working chamber are respectively connected to the inlet and outlet of the heat exchanger; the low pressure port is the oil return port, which directly communicates with the oil outlet of the heat exchanger; the rotor, shell and heat exchanger form a closed cavity; When working, there is no magnetic field in the heat exchanger; the magnetorheological fluid circulates and exchanges heat with low viscosity in the heat exchanger and exchanges heat to the coolant.
A pump-type magnetorheological fluid retarder according to claim 7, characterized in that: the heat exchanger can be arranged behind the pump or outside the casing; cooling water channels can be arranged on the casing at the same time ; The outlet to the heat exchanger adopts small or multi-hole steel plate throttling; the inlet adopts large-caliber return; the oil plug is installed on the upper side of the working cavity of the retarder body; the oil drain is installed on the lower side of the channel in the high and low pressure zone Screw plug; no need to press in or remove the medium in the working cavity.
A pump-type magnetorheological fluid retarder according to claim 5; characterized in that: the working temperature is -40°C to 160°C; the inlet and outlet are respectively arranged with an inlet temperature sensor and an outlet temperature sensor to measure the temperature of the inlet and outlet.