Active magneto-rheological actuator

Abstract

The active magneto-rheological actuator comprises an actuating assembly and an active output assembly, the actuating assembly comprises an actuator cylinder body and a magneto-rheological piston, the actuator cylinder body is provided with a first magnetic flow channel, and the magneto-rheological piston is arranged in the actuator cylinder body and divides the first magnetic flow channel into a first cavity and a second cavity; the driving output assembly comprises an outer cylinder body, a screw pump and a driving part, the outer cylinder body is provided with a second magnetic flow channel, and the screw pump is arranged in the outer cylinder body and divides the second magnetic flow channel into a third cavity and a fourth cavity. A magnet exciting coil is arranged on the magneto-rheological piston, the magneto-rheological piston is provided with a middle flow channel, an opening and closing assembly is arranged on the magneto-rheological piston, and the opening and closing assembly can be controlled to close or open the middle flow channel. The active magneto-rheological actuator is simple and compact in structure, small in occupied space and easy to implement, integrates passive, semi-active and active characteristics, can actively output force outwards, can be switched among a passive device, a semi-active device and an active device according to working conditions, and has the characteristic of energy conservation.

Description

Technical Field

[0001] The invention relates to the technical field of vibration suppression, and in particular to an active magnetorheological actuator. Background Art

[0002] Active actuators are an important part of vehicle active suspension, and play an important role in increasing vehicle life and improving riding experience. Existing active actuators are mostly hydraulically driven, which has the disadvantages of large size, complex structure, and high energy consumption.

[0003] Magnetorheological damper is a semi-active vibration reduction device with magnetorheological material as working medium. It has the characteristics of low energy consumption and compact structure. It can change the damping force by adjusting the current to achieve passive suppression of vibration, but it cannot achieve active external output force, which limits the application of magnetorheological damper in vehicle active suspension.

[0004] Therefore, combining the functions of active actuators and magnetorheological dampers and designing magnetorheological active actuators to simultaneously achieve vibration reduction and output active force is a technical problem that needs to be solved urgently. Summary of the invention

[0005] In view of this, the present invention provides an active magnetorheological actuator, which realizes two functions of vibration reduction and outputting active force, and has the characteristics of compact structure, small space occupation, simple control method and low energy consumption.

[0006] The active magnetorheological actuator provided by the present invention adopts the following technical solution:

[0007] An active magnetorheological actuator comprises an actuator assembly and an active output assembly, wherein the actuator assembly comprises an actuator cylinder and a magnetorheological piston, wherein the actuator cylinder has a magnetic flow channel 1 for magnetorheological fluid to flow, wherein the magnetorheological piston can be driven to slide in the actuator cylinder along the axial direction and separate the magnetic flow channel 1 into a cavity 1 and a cavity 2 along the axial direction, wherein the active output assembly comprises an outer cylinder, a screw pump and a driving member, wherein the outer cylinder has a magnetic flow channel 2 for magnetorheological fluid to flow, wherein the screw pump can be fixed in the outer cylinder by the driving member, wherein the screw pump separates the magnetic flow channel 2 into a cavity 3 for communication with the cavity 1 and a cavity 4 for communication with the cavity 2, wherein an excitation coil is arranged on the magnetorheological piston, wherein the magnetorheological piston has an intermediate flow channel for communication with the cavity 1 and the cavity 2, wherein an opening and closing assembly is arranged on the magnetorheological piston, wherein the opening and closing assembly can be operated to close or open the intermediate flow channel.

[0008] Optionally, it also includes a floating piston, which divides cavity two into a magnetorheological fluid chamber and a gas chamber. The magnetorheological fluid chamber is in communication with cavity four, and the gas chamber is used to store gas. The actuator cylinder is provided with an inflation valve that is in communication with the gas chamber.

[0009] Optionally, the actuator cylinder body includes an actuator cylinder barrel, an actuator left end cover and an actuator right end cover, the actuator left end cover is threadedly connected to the actuator cylinder barrel, the actuator right end cover is fixedly connected to the actuator cylinder barrel, and the inflation valve is arranged on the actuator right end cover.

[0010] Optionally, the magnetorheological piston includes a left end cover, a piston body, a right end cover and a piston sleeve. The piston sleeve is slidingly fitted on the actuator cylinder. The left end cover and the right end cover are respectively arranged on the left and right sides of the piston sleeve. The left end cover and the right end cover of the piston are both provided with through holes along their own circumference for the passage of magnetorheological fluid. A gap is formed between the outer contour of the piston body and the inner contour of the piston sleeve for circulation with the through holes.

[0011] Optionally, the opening and closing assembly includes a magnetic part, an elastic part and a baffle, the elastic part is used to apply an outward thrust to the magnetic part, and the excitation coil applies an inward magnetic force to the magnetic part after being energized. The magnetic part, driven by the elastic part and the excitation coil, drives the baffle to move axially to open or close the through hole, and the baffle has a through hole for magnetorheological fluid to flow, and the magnetorheological fluid can flow in the piston sleeve and the baffle sleeve through the through hole.

[0012] Optionally, a baffle sleeve is provided on the magnetorheological piston, a connecting hole communicating with the through hole is opened on the baffle sleeve, and the baffle is arranged in the baffle sleeve in a manipulable sliding fit.

[0013] Optionally, the screw pump consists of a bushing and a screw, the bushing is fixedly connected to the outer cylinder, the screw is rotatably arranged in the bushing, and the driving member consists of a motor, a rotating shaft and a coupling, which is used to drive the screw to rotate.

[0014] Optionally, the actuator assembly also includes a piston rod, one end of which is arranged on the magnetorheological piston, and the other end extends outward from the actuator cylinder body, the extended end of the piston rod is provided with a lifting ring 1, and the end of the actuator cylinder body away from the piston rod is provided with a lifting ring 2.

[0015] Optionally, the outer cylinder body includes an outer right end cover, an outer left end cover and an outer cylinder barrel, the outer right end cover and the outer left end cover are respectively arranged on the left and right sides of the outer cylinder barrel, and the screw pump is fixedly arranged in the outer cylinder barrel.

[0016] Optionally, the piston left end cover and the piston right end cover are made of magnetic isolation material, the piston sleeve is made of magnetic conductive material for guiding the magnetic circuit, and the piston body is provided with a circumferential receiving groove for accommodating the excitation coil.

[0017] In summary, the present invention includes at least one of the following beneficial technical effects: simple and compact structure, small space occupation, easy implementation, integrating passive, semi-active and active characteristics, can actively output force to the outside, can switch between passive devices, semi-active devices and active devices according to working conditions, and has the characteristics of energy saving. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0019] Figure 1 is a schematic diagram of the overall structure of an embodiment of the present invention;

[0020] Figure 2 is a schematic diagram of the overall structure when the magnetorheological channel of an embodiment of the present invention is opened;

[0021] Figure 3 is a schematic diagram of the overall structure when the magnetorheological channel of an embodiment of the present invention is closed;

[0022] Figure 4 is a schematic structural diagram of a baffle sleeve according to an embodiment of the present invention;

[0023] Figure 5 is a schematic structural diagram of a baffle according to an embodiment of the present invention;

[0024] Figure 6 is a schematic diagram of the magnetorheological fluid flow in passive and semi-active modes according to an embodiment of the present invention;

[0025] Figure 7 Schematic diagram of the magnetorheological fluid flow in active mode according to an embodiment of the present invention.

[0026] Explanation of the reference numerals in the accompanying drawings: 1. lifting ring one; 2. piston rod; 3. actuator left end cover; 4. actuator cylinder; 5. piston left end cover; 6. spring; 7. piston sleeve; 8. piston body; 9. armature; 10. piston right end cover; 11. baffle; 12. baffle sleeve; 13. floating piston; 14. charging valve; 15. actuator right end cover; 16. liquid pipe joint; 17. liquid pipe; 18. outer right end cover; 19. outer cylinder; 20. screw; 21. bushing; 22. coupling one; 23. rotating shaft; 24. outer left end cover; 25. coupling two; 26. motor; 27. cavity one; 28. magnetorheological fluid chamber; 29. ​​gas chamber; 30. cavity three; 31. cavity four; 32. lifting ring two. DETAILED DESCRIPTION

[0027] The following describes the embodiments of the present invention through specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention.

[0028] The following is combined with Figure 1-7 The present invention is described in further detail.

[0029] An embodiment of the present invention discloses an active magnetorheological actuator.

[0030] Reference Figure 1-Figure 7 An active magnetorheological actuator includes an actuator assembly and an active output assembly. The actuator assembly includes an actuator cylinder and a magnetorheological piston. The actuator cylinder has a magnetic flow channel 1 for magnetorheological fluid to flow. The magnetorheological piston can be driven to slide along the axial direction in the actuator cylinder 4 and divide the magnetic flow channel 1 into a cavity 1 27 and a cavity 2 along the axial direction. The active output assembly includes an outer cylinder 19, a screw pump and a driving member. The outer cylinder 19 has a magnetic flow channel 2 for magnetorheological fluid to flow. The screw pump can be fixed in the outer cylinder 19 by the driving member. The screw pump drives the magnetorheological fluid. Channel two is divided into cavity three 30 which is in communication with cavity one 27 and cavity four 31 which is in communication with cavity two. An excitation coil is arranged on the magnetorheological piston. The magnetorheological piston has an intermediate flow channel which is in communication with cavity one 27 and cavity two. An opening and closing component is arranged on the magnetorheological piston. The opening and closing component can be operated to close or open the intermediate flow channel. The structure is simple and compact, occupies little space, is easy to implement, integrates the characteristics of passive, semi-active and active, can actively output force to the outside, can switch between passive devices, semi-active devices and active devices according to working conditions, and has the characteristics of energy saving.

[0031] In this embodiment, the actuator cylinder body includes an actuator cylinder barrel 4, an actuator left end cover 3 and an actuator right end cover 15. The actuator left end cover 3 is threadedly connected to the actuator cylinder barrel 4, and the actuator right end cover 15 is fixedly connected to the actuator cylinder barrel 4 by welding.

[0032] In this embodiment, it also includes a floating piston 13, which is arranged in the actuator cylinder 4. The floating piston 13 divides the second cavity into a magnetorheological fluid chamber 28 and a gas chamber 29. The magnetorheological fluid chamber 28 is in communication with the fourth cavity 31, and the gas chamber 29 is used to store gas. The actuator cylinder 4 is provided with an inflation valve 14 that is in communication with the gas chamber 29, and the inflation valve 14 is arranged on the right end cover 15 of the actuator.

[0033] In this embodiment, the magnetorheological piston includes a piston left end cover 5, a piston body 8, a piston right end cover 10 and a piston sleeve 7. The piston sleeve 7 is slidably arranged on the actuator cylinder 4. The piston left end cover 5 and the piston right end cover 10 are respectively arranged on the left and right sides of the piston sleeve 7. The piston left end cover 5 and the piston right end cover 10 are provided with through holes for passing magnetorheological fluid along their own circumferences. A gap for passing through the through holes is formed between the outer contour of the piston body 8 and the inner contour of the piston sleeve 7. The piston left end cover 5 and the piston right end cover 10 are made of magnetic isolation material to prevent magnetic leakage. The piston sleeve 7 is made of magnetic conductive material to guide the magnetic circuit. There is a gap between the piston sleeve 7 and the piston body 8 for the circulation of magnetorheological fluid.

[0034] In this embodiment, the piston sleeve 7 is positioned and pressed and fixed with the piston left end cover 5 and the piston right end cover 10 through the boss, the piston body 8 and the piston right end cover 10 are fastened by screws, and the piston right end cover 10 and the piston body 8 are positioned through the boss and fastened by screws.

[0035] In this embodiment, the opening and closing assembly includes a magnetic part, an elastic part, a baffle 11 and a baffle sleeve 12. The right end cover 10 of the piston and the outer sleeve 12 are positioned by a groove and fastened by screws. The elastic part is used to apply an outward thrust to the magnetic part. After the excitation coil is energized, an inward magnetic force is applied to the magnetic part. Driven by the elastic part and the excitation coil, the magnetic part drives the baffle 11 to move axially to open or close the through hole. The magnetorheological fluid passes through the through hole in the piston sleeve 7 and the baffle sleeve 12. A baffle sleeve 12 is arranged on the magnetorheological piston. A connecting hole for communication with the through hole is opened on the baffle sleeve 12. The baffle 11 can be operated to slide in the baffle sleeve 12. Specifically, the elastic part is a spring 6, and the magnetic part is an armature 9. The armature 9 is installed inside the piston body 8, and the spring 6 is installed between the armature 9 and the piston rod 2. The armature 9 and the baffle 11 are fastened by screws. The armature 9 can be pushed out by the elastic force of the spring 6 when the coil does not generate a magnetic field. After the coil generates a magnetic field, it is moved inward by the electromagnetic force to overcome the elastic force of the spring 6.

[0036] The baffle 11 is located at the right end of the armature 9. The baffle 11 has a through hole for the magnetorheological fluid to flow. In the present embodiment, four through holes are provided. The magnetorheological fluid can enter the piston sleeve 7 through the through holes to balance the pressure on both sides of the baffle 11, so that the baffle 11 can move left and right under the drive of the armature 9.

[0037] In this embodiment, the screw pump includes a screw 20 and a bushing 21, the bushing 21 is fixed inside the outer cylinder 19 by welding, the screw 20 is rotatably arranged in the bushing 21, and the driving member is used to drive the screw 20 to rotate. Specifically, the driving member is a motor 26, the motor 26 is used to drive the screw 20 to rotate so as to compress the magnetorheological fluid in the corresponding chamber, the screw 20 is coaxially provided with a rotating shaft 23, a coupling 1 22 is provided between the screw 20 and the rotating shaft 23, and the motor 26 is connected to the rotating shaft 23 through a coupling 25, thereby driving the screw 20 to rotate.

[0038] In this embodiment, the actuator assembly further includes a piston rod 2 threadedly connected to the piston body 8, one end of the piston rod 2 is arranged on the magnetorheological piston, and the other end extends outward from the actuator cylinder body, and a lifting ring 1 is arranged at the extended end of the piston rod 2, and a lifting ring 2 32 is arranged at the end of the actuator cylinder body away from the piston rod 2. Among them, a channel for arranging a wire is arranged inside the piston rod 2, and the channel passes through the piston rod 2. The wire is wound around the piston body 8 to form an excitation coil, and the piston body 8 is provided with a receiving groove for accommodating the excitation coil along the circumferential direction.

[0039] In this embodiment, the outer cylinder body includes an outer right end cover 18, an outer left end cover 24 and an outer cylinder barrel 19. The outer right end cover 18 and the outer left end cover 24 are respectively arranged on the left and right sides of the outer cylinder barrel. The outer right end cover 18 and the outer cylinder barrel are connected by welding, and the outer left end cover 24 is threadedly connected to the outer cylinder barrel 19.

[0040] In this embodiment, cavity one 27 is in communication with cavity three 30 through liquid pipe 17. Similarly, cavity two is in communication with cavity four 31 through liquid pipe 17. Liquid pipe joints 16 are provided at both ends of liquid pipe 17. Liquid pipe joints 16 are used to connect with the corresponding actuator cylinder or outer cylinder to realize the exchange of magnetorheological fluid between the actuator cylinder and the outer cylinder. In this embodiment, the connection is performed by threaded connection.

[0041] When the excitation coil wound on the piston is not energized, the armature 9 is not subjected to electromagnetic force, the baffle 11 is pushed out by the spring 6 along with the armature 9, the motor 26 does not work, the magnetorheological fluid can flow in the actuator, and the actuator can act as a passive damper to dissipate vibration energy. At this time, the actuator works in a passive mode and has a vibration reduction effect.

[0042] When a small current is passed through the excitation coil wound on the piston, the electromagnetic force exerted on the armature 9 cannot overcome the elastic force of the spring 6, and the baffle 11 is pushed out with the armature 9. The connecting hole on the outer sleeve 12 for the passage of the magnetorheological fluid is connected with the through hole on the right end cover 10 of the piston for the passage of the magnetorheological fluid. The motor 26 does not work, and the magnetorheological fluid can flow in the actuator cylinder. The magnetic field strength around the piston can be adjusted by adjusting the current to change the viscosity of the magnetorheological fluid, thereby changing the damping force of the actuator and dissipating the vibration energy. At this time, the actuator works in a semi-active mode, which has a vibration reduction effect.

[0043] When a large current is passed through the excitation coil wound on the piston, the electromagnetic force exerted on the armature 9 overcomes the elastic force of the spring 6, and the baffle 11 moves to the left with the armature 9. The connecting hole on the outer sleeve 12 for the passage of the magnetorheological fluid and the through hole on the right end cover 10 of the piston for the passage of the magnetorheological fluid are blocked by the baffle 11, and the magnetorheological fluid channel is closed. At the same time, the motor 26 starts to work, driving the screw 20 to rotate, compressing the magnetorheological fluid, so that the pressure in one cavity of the outer cylinder increases and the pressure in the other cavity decreases. Under the connection of the two liquid pipes, the pressure in one cavity of the corresponding actuator cylinder increases and the pressure in the other cavity decreases. By adjusting the output speed of the motor 26, the pressure of the two cavities of the actuator cylinder can be changed, thereby changing the force acting on the left end cover 5 of the piston and the outer sleeve 12, and realizing the actuator's external output force. At this time, the actuator works in the active mode and can actively output force to the outside.

[0044] The control method of the present invention is simple, and the damping force can be adjusted by controlling the current of the excitation coil and the output force of the actuator can be indirectly controlled by controlling the motor 26, so active control can be easily realized.

[0045] This article uses specific examples to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core ideas. The above is only a preferred implementation method of the present invention. It should be pointed out that due to the limitations of textual expression, there are objectively infinite specific structures. For ordinary technicians in this technical field, without departing from the principles of the present invention, several improvements, modifications or changes can be made, and the above technical features can be combined in an appropriate manner; these improvements, modifications, changes or combinations, or the direct application of the inventive concept and technical solution to other occasions without improvement, should be regarded as the protection scope of the present invention.

Claims

1. An active magnetorheological actuator, characterized in that: The invention comprises an actuator component and an active output component, wherein the actuator component comprises an actuator cylinder and a magnetorheological piston, wherein the actuator cylinder has a magnetic flow channel 1 for magnetorheological fluid to flow, the magnetorheological piston can be driven to slide in the actuator cylinder along the axial direction and separate the magnetic flow channel 1 into cavity 1 and cavity 2 along the axial direction, the active output component comprises an outer cylinder, a screw pump and a driving member, the outer cylinder has a magnetic flow channel 2 for magnetorheological fluid to flow, the screw pump can be fixed in the outer cylinder by the driving member, the screw pump separates the magnetic flow channel 2 into cavity 3 for communication with cavity 1 and cavity 4 for communication with cavity 2, an excitation coil is arranged on the magnetorheological piston, the magnetorheological piston has an intermediate flow channel for communication with cavity 1 and cavity 2, an opening and closing component is arranged on the magnetorheological piston, and the opening and closing component can be operated to close or open the intermediate flow channel.

2. The active magnetorheological actuator according to claim 1, characterized in that: It also includes a floating piston, which divides cavity 2 into a magnetorheological fluid chamber and a gas chamber. The magnetorheological fluid chamber is in communication with cavity 4, and the gas chamber is used to store gas. The actuator cylinder is provided with an inflation valve in communication with the gas chamber.

3. The active magnetorheological actuator according to claim 1, characterized in that: The actuator cylinder body comprises an actuator cylinder barrel, an actuator left end cover and an actuator right end cover, the actuator left end cover is threadedly connected to the actuator cylinder barrel, the actuator right end cover is fixedly connected to the actuator cylinder barrel, and the inflation valve is arranged on the actuator right end cover.

4. The active magnetorheological actuator according to claim 1, characterized in that: The magnetorheological piston comprises a piston left end cover, a piston body, a piston right end cover and a piston sleeve. The piston sleeve is slidingly fitted in the actuator cylinder. The piston left end cover and the piston right end cover are respectively arranged on the left and right sides of the piston sleeve. The piston left end cover and the piston right end cover are both provided with through holes for magnetorheological fluid to pass through along their own circumferences. A gap is formed between the outer contour of the piston body and the inner contour of the piston sleeve for circulation with the through holes.

5. The active magnetorheological actuator according to claim 4, characterized in that: The opening and closing assembly includes a magnetic part, an elastic part and a baffle. The elastic part is used to apply an outward thrust to the magnetic part. When the excitation coil is energized, it applies an inward magnetic force to the magnetic part. Driven by the elastic part and the excitation coil, the magnetic part drives the baffle to move axially to open or close the through hole. The baffle has a through hole for magnetorheological fluid to flow, and the magnetorheological fluid can flow in the piston sleeve and the baffle sleeve through the through hole.

6. The active magnetorheological actuator according to claim 5, characterized in that: The magnetorheological piston is provided with a baffle sleeve, the baffle sleeve is provided with a connecting hole communicating with the through hole, and the baffle is arranged in the baffle sleeve in a manipulable sliding fit.

7. The active magnetorheological actuator according to claim 1, characterized in that: The screw pump is composed of a bushing and a screw, wherein the bushing is fixedly connected to the outer cylinder, and the screw is rotatably arranged in the bushing. The driving member is composed of a motor, a rotating shaft and a coupling, and is used to drive the screw to rotate.

8. The active magnetorheological actuator according to claim 1, characterized in that: The actuator assembly also includes a piston rod, one end of which is arranged on the magnetorheological piston and the other end extends outward from the actuator cylinder. A first lifting ring is arranged at the extended end of the piston rod, and a second lifting ring is arranged at the end of the actuator cylinder away from the piston rod.

9. The active magnetorheological actuator according to claim 1, characterized in that: The outer cylinder body comprises an outer right end cover, an outer left end cover and an outer cylinder barrel. The outer right end cover and the outer left end cover are respectively arranged on the left and right sides of the outer cylinder barrel, and the screw pump is fixedly arranged in the outer cylinder barrel.

10. The active magnetorheological actuator according to claim 4, characterized in that: The piston left end cover and the piston right end cover are made of magnetic isolation material, the piston sleeve is made of magnetic conductive material for guiding the magnetic circuit, and the piston body is provided with a receiving groove for receiving the excitation coil along the circumferential direction.

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