CN113446331B

CN113446331B - A four-motor magnetorheological fluid brake device

Info

Publication number: CN113446331B
Application number: CN202011126620.1A
Authority: CN
Inventors: 李东恒; 梁俊圆; 陈璟; 梁柏林; 陆春剑; 卞忠毅; 王富春
Original assignee: Liuzhou Vocational and Technical College
Current assignee: Liuzhou Vocational And Technical University
Priority date: 2020-10-20
Filing date: 2020-10-20
Publication date: 2024-11-19
Anticipated expiration: 2040-10-20
Also published as: CN113446331A

Abstract

The present invention discloses a four-motor magnetorheological fluid brake device, including a housing and an axle, wherein the housing is surrounded by front and rear bottom plates and side plates to form a cylindrical sealed cavity, wherein the axle passes through the front and rear bottom plates and is arranged in the sealed cavity, wherein the axle is connected to the front and rear bottom plates respectively through bearings, wherein a brake disc and two groups of magnetic conductive modules are arranged in the sealed cavity, wherein the magnetic conductive modules are respectively arranged on the bearings of the front and rear bottom plates and rotate coaxially with the axle; wherein the brake disc is arranged on the axle and located between the two groups of magnetic conductive modules and rotate coaxially with the axle; wherein heat dissipation channels are provided on the inner cavities at the upper and lower ends of the side plates. The present invention utilizes the instantaneous solidification characteristics of magnetorheological fluid after magnetization to wrap the brake disc and apply braking force, which will greatly reduce the degree of wear on the workpiece and extend the service life of the product.

Description

Four-motor magnetorheological fluid braking device

Technical Field

The invention belongs to the field of automobile braking, and particularly relates to a four-motor magnetorheological fluid braking device.

Background

The new energy automobile is an automobile which adopts unconventional automobile fuel as a power source (or adopts conventional automobile fuel and a novel automobile-mounted power device) and integrates the advanced technology in the aspects of power control and driving of the automobile, and the formed technical principle is advanced, and the automobile has a new technology and a new structure. At present, most of the brakes of new energy automobiles are still traditional brakes, namely, dry friction braking is carried out in a physical clamping mode, and workpieces can be greatly damaged in the mode.

The magnetorheological fluid has the advantages of quick response (millisecond level), low energy consumption, easy control, good durability, wide working temperature range, long service life and the like, and is widely applied to the fields of aerospace, machining, building, medical treatment and the like. The braking device can be conveniently manufactured by utilizing the characteristic of the magnetorheological fluid, but the braking device manufactured by the magnetorheological fluid at present can only use the shearing stress of the magnetorheological fluid to generate smaller braking force, so that the braking requirement of large equipment such as a new energy automobile can not be met.

Disclosure of Invention

The invention aims to solve the technical problems and provide the four-motor magnetorheological fluid braking device with large braking force and adjustability.

In order to achieve the above purpose, the technical scheme of the invention is as follows:

The four-motor magnetorheological fluid braking device comprises a shell and an axle, wherein the shell is surrounded by a front bottom plate, a rear bottom plate and side plates to form a cylindrical sealing cavity, the axle passes through the front bottom plate and the rear bottom plate to be arranged in the sealing cavity, the axle is respectively connected with the front bottom plate and the rear bottom plate through bearings, a brake disc and two groups of magnetic conduction modules are arranged in the sealing cavity, and the magnetic conduction modules are respectively arranged on the bearings of the front bottom plate and the rear bottom plate and coaxially rotate with the axle; the brake disc is arranged on the axle and positioned between the two groups of magnetic conduction modules and rotates coaxially with the axle; and inner cavities at the upper end and the lower end of the side plate are provided with heat dissipation channels.

As a further technical scheme, the brake disc comprises a brake shaft and a plurality of trapezoid annular bodies, wherein the brake shaft is wrapped on an axle, and the trapezoid annular bodies are sequentially arranged on the brake shaft at intervals.

As a further technical scheme, 4-8 rows of oblique guide holes are uniformly distributed on the trapezoid annular body along the circle center.

As a further technical scheme, the inclined guide through holes are of round hole structures or strip structures.

As a further technical scheme, a pressurizing cylinder is further arranged in the sealing cavity, the left side and the right side of the pressurizing cylinder are provided with side wings, each side wing is provided with a threaded hole in a penetrating way, the inner wall of a side plate of the shell is provided with a containing cavity for embedding the side wings to move up and down, the outer side surface of the side wings is provided with a concave sliding rail, a sliding block is clamped in the concave sliding rail, and the sliding block is fixed on the inner wall of the containing cavity; the pressurizing cylinder and the side wings are horizontally divided into an upper part and a lower part, the brake disc is arranged in the center of the pressurizing cylinder, a screw rod is arranged in threaded holes of the upper side wings and the lower side wings, the top end of the screw rod of each upper side wing is connected with an upper servo motor, the bottom end of the screw rod of each lower side wing is connected with a lower servo motor, and the upper servo motor and the lower servo motor are positioned in the accommodating cavity and are fixed on the side plates in a sealing manner; the inner walls of the upper pressurizing cylinder and the lower pressurizing cylinder are provided with a plurality of pressurizing blocks which correspond up and down, and the pressurizing blocks are aligned with the intervals of the trapezoid annular bodies and are sequentially arranged front and back.

As a further technical scheme, when the upper flank is positioned at the top end of the screw rod of the upper servo motor and the lower flank is positioned at the bottom end of the screw rod of the lower servo motor, the pressurizing block is not inserted into the interval of the trapezoid annular body; when the upper flank is positioned at the bottom end of the screw rod of the upper servo motor and the lower flank is positioned at the top end of the screw rod of the lower servo motor, the pressurizing blocks are sequentially embedded in the intervals of the trapezoid annular bodies front and back.

As a further technical scheme, the magnetic conduction module comprises a magnetic conduction cavity, a magnetic isolation ring and a coil, wherein the magnetic conduction cavity is a cylindrical cavity surrounded by a first magnetic conduction ring, a second magnetic conduction ring, a third magnetic conduction ring and a fourth magnetic conduction ring, the first magnetic conduction ring is an inner ring of the cylindrical cavity, the second magnetic conduction ring is arranged on the outer side surface of the first magnetic conduction ring, and the third magnetic conduction ring and the fourth magnetic conduction ring are the left bottom surface and the right bottom surface of the cylindrical cavity; the first magnetic conduction ring and the third magnetic conduction ring are arranged on the axle, and the magnetic isolation ring is clamped between the fourth magnetic conduction ring and the first magnetic conduction ring.

As a further technical scheme, the braking device further comprises a coil current control module, wherein the coil current control module comprises an external controller, a control circuit and an output circuit comprising a coil, the external controller is electrically connected with the input end of the control circuit, and the output end of the control circuit is electrically connected with the output circuit.

As a further technical scheme, the external controller adopts a PLC or a microcontroller.

As a further technical scheme, the control circuit includes a power VCC, a three-terminal voltage regulator U2, a capacitor C1, a capacitor C2, a chip, and resistors R1, R2, R3, R4, R5, R6, R7, R8, R9, and R10, wherein the three-terminal voltage regulator U2 employs AMS1117-5v, the chip employs L9349LF, 3 pins (i.e., VIN pins) of the three-terminal voltage regulator U2 are connected to the power VCC, 2 pins (i.e., VOUT (TAB) pins) of the three-terminal voltage regulator U2 are connected to VS pins of the chip, and the capacitor C1 and the capacitor C2 are connected across the 2 pins (i.e., VOUT (TAB) pins) and 1 pin (i.e., ADJ (GND) pins) of the three-terminal voltage regulator U2; the 4 paths of outputs OUT1, OUT2, OUT3 and OUT4 of the chip respectively correspond to PIN2, PIN9, PIN12 and PIN19, a resistor R1, a resistor R2, a resistor R5 and a resistor R6 are directly connected in series with an output channel to sample output current, and positive feedback and negative feedback of channel currents led OUT from two ends of the chip are connected with an ADC of an external controller to sample output current data; the control signal inputs corresponding to the 4 paths of outputs are IN1, IN2, IN3 and IN4 respectively, and the corresponding PINs are PIN17, PIN14, PIN7 and PIN4; the external controller is connected with the input pin to input a PWM control signal; the resistor R3, the resistor R4, the resistor R7 and the resistor R8 are pull-down resistors of the signal input end, and one end of each pull-down resistor is connected with the other end of the control signal input end and grounded; the EN terminal, namely PIN16, is an enabling terminal of the chip, namely high level is effective, when the external controller outputs high level, the chip function is activated, the resistor R9 is a pull-down resistor of the EN terminal, and the resistor R9 is connected between EN and GND in a bridging way, and the resistance is the same as four pull-down resistors of the resistor R3, the resistor R4, the resistor R7 and the resistor R8; pin1, PIN10, PIN11, PIN15, PIN20, PIN21 are circuit ground.

As a further technical scheme, the output circuit comprises a capacitor C3, a capacitor C4, a capacitor C5, a freewheeling diode D1 and a coil, wherein the head end of the coil is connected with a power supply VCC, the tail end of the coil is connected with an output channel of the control circuit, and a bypass capacitor group formed by the capacitor C3, the capacitor C4 and the capacitor C5 is connected in parallel with two ends of the power supply; the freewheeling diode D1 is reversely connected in parallel at two ends of the coil.

Compared with the prior art, the invention has the beneficial effects that:

1. the product of the invention has long service life.

The invention uses the instant solidification characteristic of the magnetorheological fluid after magnetizing to wrap the brake disc to apply braking force, thereby greatly reducing the abrasion degree to the workpiece and prolonging the service life of the product.

2. The braking force of the product is large.

The invention provides two brake structures. One is that a brake disc is arranged in the sealing cavity, the brake disc consists of a plurality of trapezoid annular bodies, and an inclined plane groove formed in the middle of the arranged trapezoid annular bodies can better contact with magnetorheological fluid and can strengthen braking force after magnetic curing; under the solidification state of the magnetorheological fluid, the magnetorheological fluid in the oblique guide through hole of the brake disc and the brake disc can have shearing action, so that the braking resistance can be increased. And the upper sealing cylinder and the lower sealing cylinder are pressurized towards the center by utilizing the motor control screw rod, and the pressurizing module in the sealing cylinder is embedded in the interval of the trapezoid annular body after being pressurized to extrude the cured magnetorheological fluid, so that the axle is more difficult to rotate, the braking force is increased, and the novel magnetorheological fluid is more suitable for new energy automobiles. The coil is circular and installed on the axle, so that the magnetic field is strong and weak from inside to outside, and the solidification degree of the magnetorheological fluid is gradually weakened from inside to outside.

3. The invention has adjustability.

According to the invention, the current of the coil is regulated by the external controller and the control circuit, so that the solidification degree of magnetorheological fluid is regulated, and the braking force is regulated; in addition, the invention can also control the pressurizing distance of the screw rod by utilizing the motor, thereby controlling the pressurizing degree of the pressurizing module.

4. The invention can prolong the service life of the magnetorheological fluid.

The invention designs a heat dissipation channel because the performance of the magnetorheological fluid begins to decay when the temperature of the magnetorheological fluid exceeds 90 ℃, and the heat dissipation area of the magnetorheological fluid is enlarged by utilizing the flow of the magnetorheological fluid in the heat dissipation channel, so that the service life of the magnetorheological fluid is prolonged.

5. The invention has stable braking effect.

Generally, the traditional magnetorheological fluid brake is only provided with an electromagnetic coil, and the magnetic force intensity is gradually weakened during magnetic conduction, so that the magnetorheological fluid is unstable to solidify. The left end and the right end of the magnetorheological fluid are respectively provided with the electromagnetic coils, so that the effect of strengthening a magnetic field and stabilizing the solidification degree of the magnetorheological fluid can be achieved; meanwhile, in the non-solidification state of the magnetorheological fluid, the oblique through hole has the function of a propeller, the axle drives the brake disc to rotate, the magnetorheological fluid circularly flows through the oblique through hole and a heat dissipation channel arranged on the inner wall of the shell, and the purpose of preventing particles in the magnetorheological fluid from precipitating is achieved, so that the braking effect of the magnetorheological fluid after solidification is maintained.

Drawings

FIG. 1 is a schematic view of the external appearance structure of a four-motor magnetorheological fluid brake device of the present invention;

FIG. 2 is a schematic diagram of the internal structure of a four-motor magnetorheological fluid brake apparatus according to the present invention;

FIG. 3 is a schematic view of the structure within the pressure cylinder of the present invention;

FIG. 4 is a schematic view of the structure of the seal chamber of the present invention;

FIG. 5 is a schematic view of the structure of a brake disc of the present invention;

FIG. 6 is a schematic view of the inner wall of the half side plate of the present invention;

FIG. 7 is a schematic view of the structure of the upper pressurizing cylinder of the present invention;

FIG. 8 is a schematic view of a trapezoid annular body with a round hole structure and an inclined guide through hole;

FIG. 9 is a cross-sectional view of the trapezoidal ring body of FIG. 8;

FIG. 10 is a schematic view of a first configuration of a trapezoid annular body with a bar-shaped structure and an inclined through hole;

FIG. 11 is a schematic view of a second configuration of a trapezoid annular body with a bar-shaped structure and an inclined through hole;

fig. 12 is a schematic structural diagram of a magnetic conduction module according to the present invention;

Fig. 13 is an exploded view of the magnetically permeable module of fig. 8;

FIG. 14 is a control schematic diagram of a coil current control module of the present invention;

FIG. 15 is an output circuit diagram of the present invention;

fig. 16 is a control circuit diagram of the present invention.

Reference numerals: 1-shell, 2-axle, 3-bottom plate, 4-side plate, 5-bearing, 6-brake disc, 601-brake shaft, 602-trapezoid annular body, 603-oblique guide through hole, 7-heat dissipation channel, 8-pressurizing cylinder, 801-upper pressurizing cylinder, 802-lower pressurizing cylinder, 9-magnetic conduction module, 901-first magnetic conduction ring, 902-second magnetic conduction ring, 903-third magnetic conduction ring, 904-fourth magnetic conduction ring, 905-magnetism isolation ring, 906-coil, 10-flank, 1001-upper flank, 1002-lower flank, 11-threaded hole, 12-holding cavity, 13-concave slide rail, 14-slide block, 15-lead screw, 16-upper servo motor, 17-lower servo motor, 18-pressurizing block, 19-external controller, 20-control circuit; a-front, b-rear, c-top, d-bottom, e-left, f-right.

Detailed Description

The present invention will be described in further detail with reference to examples, but the embodiments of the present invention are not limited to the scope indicated by the examples.

Example 1:

as shown in fig. 1-7, a four-motor magnetorheological fluid braking device comprises a shell 1 and an axle 2, wherein the shell 1 is surrounded by a front bottom plate 3, a rear bottom plate 3 and a side plate 4 to form a cylindrical sealing cavity, the axle 2 passes through the front bottom plate 3 and the rear bottom plate 3 to be arranged in the sealing cavity, the axle 2 is respectively connected with the front bottom plate 3 and the rear bottom plate 3 through bearings 5, a brake disc 6 and two groups of magnetic conduction modules are arranged in the sealing cavity, and the magnetic conduction modules are respectively arranged on the bearings 5 of the front bottom plate 3 and the rear bottom plate 3 and rotate coaxially with the axle 2; the brake disc 6 is arranged on the axle 2 and positioned between the two groups of magnetic conduction modules and rotates coaxially with the axle 2; the inner cavities at the upper end and the lower end of the side plate 4 are provided with heat dissipation channels 7, so that the magnetorheological fluid can flow and dissipate heat conveniently, the heat dissipation area is enlarged, and the service life of the magnetorheological fluid is prolonged.

The brake disc 6 comprises a brake shaft 601 and a plurality of trapezoid annular bodies 602, the brake shaft 601 is wrapped on the axle 2, and the trapezoid annular bodies 602 are sequentially arranged on the brake shaft 601 at intervals.

The sealing cavity is internally provided with a pressurizing cylinder 8, the left side and the right side of the pressurizing cylinder 8 are provided with side wings 10, each side wing 10 is communicated with a threaded hole 11, the inner wall of the side plate 4 of the shell 1 is provided with a containing cavity 12 for embedding the side wings 10 to move up and down, the outer side surface of the side wings 10 is provided with a concave sliding rail 13, a sliding block 14 is clamped in the concave sliding rail 13, and the sliding block 14 is fixed on the inner wall of the containing cavity 12; the pressurizing cylinder 8 and the side wings 10 are horizontally divided into an upper part and a lower part, the brake disc 6 is arranged at the center of the pressurizing cylinder 8, a screw rod 15 is arranged in a threaded hole 11 of each of the upper side wings 1002, the top end of the screw rod 15 of each of the upper side wings 1001 is connected with an upper servo motor 16, the bottom end of the screw rod 15 of each of the lower side wings 1002 is connected with a lower servo motor 17, and the upper servo motor 16 and the lower servo motor 17 are positioned in the accommodating cavity 12 and are fixed on the side plates 4 in a sealing manner; the inner walls of the upper pressurizing cylinder 801 and the lower pressurizing cylinder 802 are provided with a plurality of pressurizing blocks 18 which correspond up and down, and the pressurizing blocks 18 are aligned with the interval of the trapezoid annular body 602 and are sequentially arranged in front and back.

When the upper flank 1001 is located at the top end of the screw rod 15 of the upper servo motor 16 and the lower flank 1002 is located at the bottom end of the screw rod 15 of the lower servo motor 17, the pressurizing block 18 is not inserted into the space of the trapezoid annular body 602; when the upper flank 1001 is located at the bottom end of the screw 15 of the upper servo motor 16 and the lower flank 1002 is located at the top end of the screw 15 of the lower servo motor 17, the pressing blocks 18 are sequentially fitted in the intervals of the trapezoid annular body 602.

As shown in fig. 8-9, 4 rows of oblique through holes 603 are uniformly distributed on the trapezoid annular body 602 along the circle center, the oblique through holes 603 have the function of a propeller, the axle 2 drives the brake disc 6 to rotate, and the magnetorheological fluid circularly flows through the oblique through holes 603 and a heat dissipation channel 7 arranged on the inner wall of the shell, so that the particle precipitation in the magnetorheological fluid is prevented, and the braking effect of the magnetorheological fluid after solidification is maintained.

The inclined guide through hole 603 has a circular hole structure.

As shown in fig. 12-13, the magnetic conduction module 9 includes a magnetic conduction cavity, a magnetism isolating ring 905 and a coil 906, where the magnetic conduction cavity is a cylindrical cavity surrounded by a first magnetic conduction ring 901, a second magnetic conduction ring 902, a third magnetic conduction ring 903 and a fourth magnetic conduction ring 904, the first magnetic conduction ring 901 is an inner ring of the cylindrical cavity, the second magnetic conduction ring 902 is disposed on an outer side surface of the first magnetic conduction ring 901, and the third magnetic conduction ring 903 and the fourth magnetic conduction ring 904 are left and right bottom surfaces of the cylindrical cavity; the first magnetic conduction ring 901 and the third magnetic conduction ring 903 are installed on the axle 222, and a magnetic isolation ring 905 is clamped between the fourth magnetic conduction ring 904 and the first magnetic conduction ring 901.

Example 2:

The inclined through hole 603 has an S-shaped bar-shaped structure.

Example 3:

As shown in fig. 14, on the basis of embodiment 1 or embodiment 2, the circuit of the present invention includes a coil current control module, the coil current control module includes an external controller 19, a control circuit 20 and an output circuit including a coil, the external controller 19 is electrically connected to an input terminal of the control circuit 20, and an output terminal of the control circuit 20 is electrically connected to the output circuit.

The external controller 19 can be controlled by various PLCs, microcontrollers or other controllers, and the invention takes the mature Arduino development board as the controller to control the channel 1 for output; the development board digital signal output port 9 is used as an output port of the PWM control signal and is connected with the signal input port 1 (input channel 1-PWM signal input in fig. 16) of the control circuit 20; the digital signal port 10 of the development board is connected with the enabling end (enabling pin in fig. 16) of the control circuit 20, and the high-low level is output through the control port 10 to control whether the power driving chip works or not. The analog signal port A0 of the Arduino development board is connected with the current sampling output port of the control circuit 20, and the voltage at two ends of the sampling resistor is read through an internal ADC to obtain the current information.

As shown in fig. 16, since the maximum current required for the magnetorheological brake is 3A, the control circuit 20 uses the power control chip L9349LF of an artificial semiconductor as a core device, and the maximum load current is 5A, so that the control requirement of the magnetorheological brake can be completely satisfied. The working voltage of the chip is 4.5-32V, and the chip is provided with 4 output channels which can be controlled independently, and can conveniently control the load current by controlling the duty ratio of an input PWM signal so as to control the brake to brake.

U2 in FIG. 16 is a three-terminal voltage regulator, which converts the power VCC into 5V to power VIN, VOUT (TAB), and ADJ (GND) of the logic circuit of the chip, which are the power input, 5V output, and ground pins, respectively. Wherein pin 3 (i.e., VIN) is connected to a power supply VCC. VOUT (TAB) is connected to the VS PIN (PIN 5) of the chip to power the logic circuits within the chip. The capacitors C1 and C2 are filter capacitors with 5V logic power supply of the chip and are connected between VOUT (TAB) and ADJ (GND) of the three-terminal voltage regulator U2 in a bridging mode, and the capacities of the capacitors C1 and C2 are 100uf and 0.1uf respectively.

The 4 paths of outputs OUT1 (5A), OUT2 (5A), OUT3 (3A) and OUT4 (3A) of the chip respectively correspond to PIN2, PIN9, PIN12 and PIN19, resistors R1, R2, R5 and R6 are directly connected in series with an output channel, the resistance value of the resistors is 0.1 ohm, positive feedback of channel (channel number) current and negative feedback of channel (channel number) current led OUT from two ends of the resistors are connected with an ADC (analog-digital converter) of an external controller 19 to sample output current data, and the corresponding measuring range is 100mv/1A. The control signal inputs corresponding to the 4-way outputs are IN1, IN2, IN3, IN4, and the corresponding PINs are PIN17, PIN14, PIN7, PIN4, respectively. The external controller 19 inputs the PWM control signal by being connected to the input pin, and controls the current level of the output channel by controlling the duty ratio of the PWM signal to be changed, and the output current is larger as the signal duty ratio is larger. The resistor R3, the resistor R4, the resistor R7 and the resistor R8 are pull-down resistors at the signal input end, the resistance is 10 kiloohms, one end of each pull-down resistor is connected to the other end of the control signal input end and grounded, and the effect is to prevent the chip from being opened by mistake when no signal input is interfered. The EN terminal (PIN 16) is an enable terminal (active high level) of the chip, which determines whether the chip is activated for use, when the external controller 19 outputs the high level, the chip functions are activated, the resistor R9 is a pull-down resistor of the EN terminal, and the resistor R9 is connected between EN and GND in a bridging manner, and has the same resistance as the other four pull-down resistors, so as to ensure that the chip is not turned on by mistake when no signal is input. Pin1, PIN10, PIN11, PIN15, PIN20, PIN21 are circuit ground.

Table 1 shows the function of the chip and the pins of the three-terminal voltage regulator U2

As shown in fig. 15, the head end of the coil 906 is connected to the power VCC, the tail end is connected to the output channel of the circuit, and a bypass capacitor group consisting of 310 uf capacitors C3, C4 and C5 is connected in parallel to two ends of the power, so as to improve the transient response capability of the brake. The flywheel diode D1 is connected in anti-parallel to the two ends of the magnetorheological brake coil 906, so as to prevent the induced electromotive force breakdown circuit from damaging the circuit when the state is switched from the braking state to the non-braking state, and improve the safety and stability.

When the automobile is in normal running, the servo motor and the coil are not electrified, the magnetorheological fluid is in a liquid state, the whole braking device rotates along with the axle 2, at the moment, the upper flank 1001 is positioned at the top end of the screw rod 15 of the upper servo motor 16, the lower flank 1002 is positioned at the bottom end of the screw rod 15 of the lower servo motor 17, and the pressurizing block 18 is not inserted into the interval of the trapezoid annular body 602; when the automobile brakes, the coil is electrified to enable the magnetorheological fluid to be in a solid state instantly, the solidified magnetorheological fluid generates braking force for preventing the brake disc 6 from rotating, the brake disc 6 is wrapped on the axle 2, and further rotation of the axle 2 is prevented, and braking is achieved. Meanwhile, the upper servo motor 16 and the lower servo motor 17 can be started, the upper servo motor 16 and the lower servo motor 17 drive the screw rod 15 to rotate, the concave sliding rail 13 of the upper flank 1001 moves downwards along the sliding block 14, the concave sliding rail 13 of the lower flank 1002 moves upwards along the sliding block 14, the upper flank 1001 moves to the bottom end of the screw rod 15 of the upper servo motor 16, the lower flank 1002 moves to the top end of the screw rod 15 of the lower servo motor 17, the pressurizing block 18 is embedded in the interval of the trapezoid annular body 602, and the solidified magnetorheological fluid is extruded, so that the resistance of the solidified magnetorheological fluid to the brake disc 6 is increased, and the braking force is further increased.

Example 3:

As shown in fig. 14, on the basis of embodiment 1 or embodiment 2, the circuit of the present invention includes a coil current control module, the coil current control module includes an external controller, a control circuit and an output circuit including a coil, the external controller is electrically connected with an input end of the control circuit, and an output end of the control circuit is electrically connected with the output circuit.

The external controller can be controlled by various PLCs, microcontrollers or other controllers, and the invention takes the mature Arduino development board as the controller to control the channel 1 for output as an example; the development board digital signal output port 9 is used as an output port of a PWM control signal and is connected with a signal Input port 1 (Input channel-1-PWM in FIG. 14) of a control circuit; the digital signal port 10 of the development board is connected with the enabling end (the Enable pin in fig. 14) of the control circuit, and the high-low level is output through the control port 10 to control whether the power driving chip works or not. The analog signal port A0 of the Arduino development board is connected with a current sampling output port of the control circuit, and the voltage at two ends of the sampling resistor is read through an internal ADC to obtain current information.

As shown in fig. 16, since the maximum current required for the magnetorheological brake is 3A, the control circuit 21 uses the power control chip L9349LF of an artificial semiconductor as a core device, and the maximum load current is 5A, so that the control requirement of the magnetorheological brake can be completely satisfied. The working voltage of the chip is 4.5-32V, and the chip is provided with 4 output channels which can be controlled independently, and can conveniently control the load current by controlling the duty ratio of an input PWM signal so as to control the brake to brake.

AMS1117-5V in fig. 16 is a three-terminal regulator U2, which is used to convert the power VCC into 5V L9349LF logic circuits, i.e., VIN, VOUT (TAB), and ADJ (GND) are the power input, 5V output, and ground pins, respectively. Wherein pin 3 (i.e., VIN) is connected to a power supply VCC. VOUT (TAB) is connected to the VS PIN (PIN 5) of L9349LF to power logic circuits within the chip. The capacitor C1 and the capacitor C2 are filter capacitors which are logically powered by the chip 5V and are connected between the VOUT (TAB) and the ADJ (GND) of AMS1117-5V in a bridging mode, and the capacities of the capacitor C1 and the capacitor C2 are 100uf and 0.1uf respectively.

The 4 paths of outputs OUT1 (5A), OUT2 (5A), OUT3 (3A) and OUT4 (3A) of the L9349LF chip respectively correspond to PIN2, PIN9, PIN12 and PIN19, resistors R1, R2, R5 and R6 are directly connected in series with output channels, the resistance value of the resistors is 0.1 ohm, channels current detection + led OUT from two ends of the resistors are connected with channels current detection-and ADC of the external controller 1220 to sample output current data, and the corresponding measuring range is 100mv/1A. The control signal inputs corresponding to the 4-way outputs are IN1, IN2, IN3, IN4, and the corresponding PINs are PIN17, PIN14, PIN7, PIN4, respectively. The external controller 1220 inputs the PWM control signal by being connected to the input pin, and controls the current magnitude of the output channel by controlling the duty ratio of the PWM signal to be changed, and the output current is greater as the signal duty ratio is greater. The resistor R3, the resistor R4, the resistor R7 and the resistor R8 are pull-down resistors at the signal input end, the resistance is 10 kiloohms, one end of each pull-down resistor is connected to the other end of the control signal input end and grounded, and the effect is to prevent the L9349LF chip from being opened by mistake when no signal input is interfered. The EN terminal (PIN 16) is the enable terminal (active high level) of the L9349LF chip, which determines whether the chip is activated for use, and when the external controller 1220 outputs a high level, the chip functions are activated, and the resistor R9 is a pull-down resistor of the EN terminal and is connected between EN and GND, and the resistance is the same as the other four pull-down resistors, so as to ensure that the chip is not turned on by mistake when no signal is input. Pin1, PIN10, PIN11, PIN15, PIN20, PIN21 are circuit ground.

When the automobile normally runs, the servo motor and the coil are not electrified, the magnetorheological fluid is in a liquid state, the whole braking device rotates along with the axle, at the moment, the upper side wing is positioned at the top end of the screw rod of the upper servo motor, the lower side wing is positioned at the bottom end of the screw rod of the lower servo motor, and the pressurizing block is not inserted into the interval of the trapezoid annular body; when the automobile brakes, the coil is electrified to enable the magnetorheological fluid to be in a solid state instantly, the solidified magnetorheological fluid generates braking force for preventing the brake disc from rotating, the brake disc is wrapped on the axle, and further rotation of the axle is prevented, so that braking is achieved. Meanwhile, the upper servo motor and the lower servo motor can be started, the upper servo motor and the lower servo motor drive the screw rod to rotate, the concave sliding rail of the upper flank moves downwards along the sliding block, the concave sliding rail of the lower flank moves upwards along the sliding block, the upper flank moves to the bottom end of the screw rod of the upper servo motor, the lower flank moves to the top end of the screw rod of the lower servo motor, the pressurizing blocks are embedded in the intervals of the trapezoid annular bodies, the solidified magnetorheological fluid is extruded, the resistance of the solidified magnetorheological fluid to the brake disc is increased, and the braking force is further increased.

In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "front", "rear", "left", "right", "front", "rear", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. indicate orientations or positional relationships based on the drawings, are merely for convenience in describing the present invention and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the scope of the present invention. It should also be noted that unless explicitly stated or limited otherwise, terms such as "connected," "coupled," and the like should be construed broadly and may be, for example, a fixed connection; may be a detachable connection; or may be a point connection; may be a direct connection; the connection may be indirect through an intermediary, and the communication between the two components may be made, so that the specific meaning of the terms in the present invention may be understood in specific cases by those skilled in the art. The connection modes of the devices, which are not described in detail in the present invention, are all understood in the conventional connection modes in the art.

The above embodiments are merely specific examples for further detailed description of the object, technical solution and advantageous effects of the present invention, and the present invention is not limited thereto. Any modification, equivalent replacement, improvement, etc. made within the scope of the present disclosure are included in the scope of the present invention.

Claims

1. The utility model provides a four motor magnetorheological suspensions arresting gear, includes casing and axletree, the casing is enclosed into a cylindric sealed chamber by front and back bottom plate and curb plate, the axletree passes front and back bottom plate setting in sealed intracavity, and the axletree passes through the bearing and is connected its characterized in that with front and back bottom plate respectively: a brake disc and two groups of magnetic conduction modules are arranged in the sealing cavity, and the magnetic conduction modules are respectively arranged on bearings of the front bottom plate and the rear bottom plate and coaxially rotate with the axle; the brake disc is arranged on the axle and positioned between the two groups of magnetic conduction modules and rotates coaxially with the axle; the inner cavities at the upper end and the lower end of the side plate are provided with heat dissipation channels;

the brake disc comprises a brake shaft and a plurality of trapezoid annular bodies, the brake shaft is wrapped on an axle, and the trapezoid annular bodies are sequentially arranged on the brake shaft at intervals from front to back;

The sealing cavity is internally provided with a pressurizing cylinder, the left side and the right side of the pressurizing cylinder are provided with side wings, each side wing is provided with a threaded hole in a penetrating way, the inner wall of a side plate of the shell is provided with a containing cavity for embedding the side wings to move up and down, the outer side surface of each side wing is provided with a concave sliding rail, a sliding block is clamped in each concave sliding rail, and the sliding block is fixed on the inner wall of the containing cavity; the pressurizing cylinder and the side wings are horizontally divided into an upper part and a lower part, the brake disc is arranged in the center of the pressurizing cylinder, a screw rod is arranged in threaded holes of the upper side wings and the lower side wings, the top end of the screw rod of each upper side wing is connected with an upper servo motor, the bottom end of the screw rod of each lower side wing is connected with a lower servo motor, and the upper servo motor and the lower servo motor are positioned in the accommodating cavity and are fixed on the side plates in a sealing manner; the inner walls of the upper pressurizing cylinder and the lower pressurizing cylinder are provided with a plurality of pressurizing blocks which correspond up and down, and the pressurizing blocks are aligned with the intervals of the trapezoid annular bodies and are sequentially arranged front and back;

When the upper flank is positioned at the top end of the screw rod of the upper servo motor and the lower flank is positioned at the bottom end of the screw rod of the lower servo motor, the pressurizing block is not inserted into the interval of the trapezoid annular body; when the upper flank is positioned at the bottom end of the screw rod of the upper servo motor and the lower flank is positioned at the top end of the screw rod of the lower servo motor, the pressurizing blocks are sequentially embedded in the interval of the trapezoid annular body front and back;

The magnetic conduction module comprises a magnetic conduction cavity, a magnetism isolating ring and a coil, wherein the magnetic conduction cavity is a cylindrical cavity surrounded by a first magnetic conduction ring, a second magnetic conduction ring, a third magnetic conduction ring and a fourth magnetic conduction ring, the first magnetic conduction ring is an inner ring of the cylindrical cavity, the second magnetic conduction ring is arranged on the outer side surface of the first magnetic conduction ring, and the third magnetic conduction ring and the fourth magnetic conduction ring are the left bottom surface and the right bottom surface of the cylindrical cavity; the first magnetic conduction ring and the third magnetic conduction ring are arranged on the axle, and the magnetic isolation ring is clamped between the fourth magnetic conduction ring and the first magnetic conduction ring.

2. The four-motor magnetorheological fluid brake apparatus according to claim 1, wherein: 4-8 rows of oblique guide holes are uniformly distributed on the trapezoid annular body along the circle center.

3. The four-motor magnetorheological fluid brake apparatus according to claim 2, wherein: the inclined guide through holes are of round hole structures or strip-shaped structures.

4. The four-motor magnetorheological fluid brake apparatus according to claim 1, wherein: the coil current control module comprises an external controller, a control circuit and an output circuit comprising a coil, wherein the external controller is electrically connected with the input end of the control circuit, and the output end of the control circuit is electrically connected with the output circuit; the external controller adopts a PLC or a microcontroller.

5. The four-motor magnetorheological fluid brake apparatus according to claim 4, wherein: the control circuit comprises a power supply VCC, a three-terminal voltage regulator U2, a capacitor C1, a capacitor C2, a chip, a resistor R1, a resistor R2, a resistor R3, a resistor R4, a resistor R5, a resistor R6, a resistor R7, a resistor R8, a resistor R9 and a resistor R10, wherein the three-terminal voltage regulator U2 adopts AMS1117-5v, the chip adopts L9349LF, the 3 pin of the three-terminal voltage regulator U2 is connected with the power supply VCC, the 2 pin of the three-terminal voltage regulator U2 is connected with the VS pin of the chip, and the capacitor C1 and the capacitor C2 are connected between the 2 pin and the 1 pin of the three-terminal voltage regulator U2 in a bridging manner; the 4 paths of outputs OUT1, OUT2, OUT3 and OUT4 of the chip respectively correspond to PIN2, PIN9, PIN12 and PIN19, a resistor R1, a resistor R2, a resistor R5 and a resistor R6 are directly connected in series with an output channel to sample output current, and positive feedback and negative feedback of channel currents led OUT from two ends of the chip are connected with an ADC of an external controller to sample output current data; the control signal inputs corresponding to the 4 paths of outputs are IN1, IN2, IN3 and IN4 respectively, and the corresponding PINs are PIN17, PIN14, PIN7 and PIN4; the external controller is connected with the input pin to input a PWM control signal; the resistor R3, the resistor R4, the resistor R7 and the resistor R8 are pull-down resistors of the signal input end, and one end of each pull-down resistor is connected with the other end of the control signal input end and grounded; the EN terminal, namely PIN16, is an enabling terminal of the chip, namely high level is effective, when the external controller outputs high level, the chip function is activated, the resistor R9 is a pull-down resistor of the EN terminal, and the resistor R9 is connected between EN and GND in a bridging way, and the resistance is the same as four pull-down resistors of the resistor R3, the resistor R4, the resistor R7 and the resistor R8; pin1, PIN10, PIN11, PIN15, PIN20, PIN21 are circuit ground.

6. The four-motor magnetorheological fluid brake apparatus according to claim 5, wherein: the output circuit comprises a capacitor C3, a capacitor C4, a capacitor C5, a freewheeling diode D1 and a coil, wherein the head end of the coil is connected with a power supply VCC, the tail end of the coil is connected with an output channel of the control circuit, and a bypass capacitor group formed by the capacitor C3, the capacitor C4 and the capacitor C5 is connected in parallel with two ends of the power supply; the freewheeling diode D1 is reversely connected in parallel at two ends of the coil.