Magnetorheological coupler with multiple excitation coils

Abstract

The invention discloses a magneto-rheological coupler with multiple magnet exciting coils. The magneto-rheological coupler comprises a static magnet exciting coil assembly and a rotary transmission assembly arranged in the static magnet exciting coil assembly. Magnetorheological fluid is used as a transmission medium, the viscosity of the magnetorheological fluid is changed by adjusting exciting current by utilizing the characteristic that the viscosity of the magnetorheological fluid is adjustable, the input rotating speed required for starting a driven part is changed, and output rotating speed / torque control is achieved. A working magnetic field is generated by electrifying multiple excitation coils at the same time, the current stabilization time of the excitation coils is shortened, and the response speed of the device is increased; a plurality of same magnet exciting coils are connected in parallel to supply power, so that a uniform working magnetic field can be generated; the pump wheel and the turbine are symmetrically arranged, a sealed working cavity is formed in the pump wheel and the turbine, the cavity is filled with magnetorheological fluid, the pump wheel and the turbine are both provided with blades, the unstable phenomenon occurring during circulation diversion is reduced, and power output is controlled in real time according to the load requirement.

Description

Technical Field

[0001] The invention relates to the technical field of mechanical power transmission, in particular to a multi-excitation coil magnetorheological coupler. Background Art

[0002] Magnetorheological fluid is a typical intelligent material, mainly composed of soft magnetic particles, base carrier fluid and surface additives. It has the advantages of rapid response, controllable and reversible, and low control energy consumption. Its basic characteristics are: under the action of an external magnetic field, the particles in the magnetorheological fluid form fiber bundle chains along the direction of the magnetic field, hindering the free flow of the base carrier fluid, so that the magnetorheological fluid is transformed from a Newtonian fluid to a viscoplastic fluid with a certain shear force, and a strong "solidification" phenomenon occurs. When the external magnetic field disappears, the magnetorheological fluid returns to a free-flowing state (liquid state), and this transformation is reversible. Magnetorheological fluid has the advantages of fast response speed, reversible change, and simple control. It has been widely used in clutches, shock absorbers, dampers, brakes, polishing devices, composite components and other fields, and has broad application prospects.

[0003] The hydraulic coupling usually uses liquids such as water and oil as the transmission medium in the cavity. When working, the active shaft blades push the liquid to rotate. After the liquid is pumped into the coupler, it pushes the turbine to rotate, thereby driving the driven side motor shaft to rotate and complete the power output. The viscosity of traditional transmission media such as water and oil is fixed. During transmission, the speed of the active shaft blades required for the turbine rotation cannot be adjusted, and the output speed cannot be adjusted. During the transmission process, the coupler will produce abnormal temperature and pressure inside the coupler due to overload, frequent start and stop, aging of components, etc., which will affect the metal strength of the equipment and threaten the problem of stable power output.

[0004] The spiral circulation movement of the liquid in the working chamber of the hydraulic coupling is usually referred to as circulation. The circulation has different forms under different working conditions (speed ratios). When the circulation is diverted, it is very easy to cause the transmission torque to fluctuate non-uniformly and become unstable, so that the output torque and speed cannot be accurately transmitted. Summary of the invention

[0005] The object of the present invention is to provide a multi-excitation coil magnetorheological coupler, which uses a magnetorheological fluid with adjustable viscosity as a transmission medium, controls the magnetic field to change the viscosity of the transmission medium, and pushes the blades through the magnetorheological fluid. The viscosity of the magnetorheological fluid is changed by adjusting the excitation current, and the input speed required for starting the driven rotating component is changed, and the output speed / torque control is realized, thereby reducing the instability phenomenon that occurs when the circulation is diverted, and controlling the power output in real time according to the load demand.

[0006] To achieve the above object, the specific technical solution of a multi-excitation coil magnetorheological coupler of the present invention is as follows: A multi-excitation coil magnetorheological coupler comprises a stationary excitation coil assembly and a rotating transmission assembly disposed inside the stationary excitation coil assembly; The stationary excitation coil assembly is composed of excitation coils arranged in parallel; The rotary transmission assembly includes a driving rotary assembly and a driven rotary assembly; The active rotating assembly is composed of an input shaft, a magnetically conductive left side plate, a pump wheel, a bearing, a housing, and a magnetically conductive right side plate which are fixedly connected in sequence; The driven rotating assembly is composed of a turbine fixedly connected to an output shaft via a bearing; The pump wheel and the turbine are detachably closed, and a sealed cavity is formed inside, and the cavity is filled with magnetorheological fluid; The pump wheel and the turbine wheel are arranged symmetrically, and blades are arranged inside them; A plurality of blades are evenly spaced and arranged, and a blade cavity is formed between two adjacent blades. The blade cavity gradually increases from the inner diameter to the outer diameter, and the blades are all inclined in the same direction by 0°-10°.

[0007] Furthermore, the excitation coil is composed of a plurality of excitation coils having the same number of turns, size and winding direction.

[0008] Furthermore, the current flowing through the excitation coil has the same magnitude and direction.

[0009] Furthermore, the shell is a fixed magnetically conductive shell.

[0010] Furthermore, the pump wheel and the turbine are fixedly connected by bolts.

[0011] Furthermore, a sealing strip is provided at the junction of the pump wheel and the turbine wheel rim.

[0012] Furthermore, the blades are made of alloy material.

[0013] Furthermore, convex bodies are evenly spaced and arranged on both sides of the blade.

[0014] Beneficial effects of the present invention: 1. Use magnetorheological fluid as the working fluid, and take advantage of its controllable power output characteristics to adjust the output torque as needed; generate a working magnetic field by energizing multiple excitation coils at the same time, reduce the stabilization time of the excitation coil current, and improve the response speed of the device; use multiple identical excitation coils to supply power in parallel. This can generate a uniform working magnetic field, because the magnetic fields generated by multiple small excitation coils can be superimposed and will not cancel each other out. The device omits the fixed magnetic shell (i.e., magnetic yoke) to reduce hysteresis and eddy current phenomena in the magnetic circuit and improve the magnetic field response speed.

[0015] 2. The pump wheel and turbine are arranged symmetrically, forming a sealed working chamber inside. The chamber is filled with magnetorheological fluid. Both the pump wheel and the turbine are provided with blades, which are pushed by the magnetorheological fluid to control the power transmission, reduce the instability phenomenon that occurs when the circulation is diverted, and control the power output in real time according to the load demand.

[0016] 3. The transmission medium between the pump wheel and the turbine is magnetorheological fluid, which has the characteristic of adjustable viscosity. By adjusting the excitation current to change the viscosity of the magnetorheological fluid, the input speed required for starting the driven component can be changed, and the output speed / torque control can be achieved. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic diagram of the overall structure of the present invention; Figure 2 It is a schematic diagram of the pump wheel; Figure 3 It is a schematic diagram of a turbine; In the figure: 1. input shaft, 2. magnetic left side plate, 3. pump wheel, 4. excitation coil, 5. magnetorheological fluid, 6. turbine, 7. bearing, 8. housing, 9. magnetic right side plate, 10. output shaft, 11. blades. DETAILED DESCRIPTION

[0018] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0019] like Figures 1 to 3 As shown, the multi-excitation coil magnetorheological coupler comprises a stationary excitation coil assembly and a rotating transmission assembly placed inside the stationary excitation coil assembly; the stationary excitation coil assembly is composed of a plurality of excitation coils 4 arranged in parallel, and power is supplied to the plurality of excitation coils 4 simultaneously through a current source to generate a variable magnetic field in the working gap of the magnetorheological fluid 5, and the rotating transmission assembly placed inside the stationary excitation coil assembly is acted upon by the variable magnetic field; the rotating transmission assembly comprises an active rotating assembly and a driven rotating assembly; the active rotating assembly is composed of an input shaft 1, a magnetically conductive left side plate 2, a pump wheel 3, a bearing 7, a housing 8, and a magnetically conductive right side plate 9 which are fixedly connected in sequence, and is connected to a power mechanism; the driven rotating assembly is composed of a turbine 6 which is fixedly connected to an output shaft 10 through a bearing 7, and can be connected to an actuator; Use multiple identical excitation coils 4 to supply power in parallel, and set the same current magnitude and direction for the excitation coils 4. In this way, a uniform working magnetic field can be generated, without local magnetic field deviation, and can be superimposed on each other. The pump wheel 3 and the turbine 6 are arranged symmetrically, and the two are detachably closed, forming a sealed cavity inside, and the cavity is filled with magnetorheological fluid 5. The pump wheel 3 and the turbine 6 are arranged symmetrically, and a certain number of blades 11 are arranged inside. A blade cavity is formed between two adjacent blades 11, and its volume gradually increases with the increase of radial size. The blades 11 are all inclined in the same direction, and the inclination angle can be set to 0°-10°; preferably, the blade inclination angle is 8°, which can effectively improve the stability of the spiral circulation motion of the magnetorheological fluid in the cavity. By controlling the magnetic field to change the viscosity of the transmission medium, and by pushing the blades 11 through the magnetorheological fluid 5 to control the power transmission, the instability phenomenon that occurs when the circulation is diverted is reduced, and the power output is controlled in real time according to the load demand. In addition, this structure can effectively gather the working magnetic field in the working gap of the magnetorheological fluid 5 to reduce the loss of the magnetic field. In this way, the magnetic yoke can be omitted, that is, there is no "hysteresis" and "eddy current" phenomenon that prevents the working magnetic field from being rapidly enhanced, and the working magnetic field generated by the magnetorheological fluid 5 is generated at a faster speed. At the same time, the working magnetic field is generated by the current flowing through multiple small excitation coils 4 at the same time. The resistance and inductance of a single coil are small, and the magnetic field generation speed is also faster. The above structure speeds up the generation time of the working magnetic field and effectively improves the response speed of the coupler.

[0020] When the impeller 3 rotates, the magnetorheological fluid 5 is clamped by the blades 11 and rotates together with the impeller 3, thereby generating centrifugal force. The liquid particles in the impeller 3 are acted upon by the centrifugal force, flowing from the inlet of the impeller 3 to the outlet of the impeller 3, and then flowing from the inlet of the turbine 6 to the outlet of the turbine 6 again, and finally entering the inlet of the impeller 3 again to form a circular flow. The magnetorheological fluid 5 continuously circulates and impacts the turbine 6, thereby driving the turbine 6 to rotate.

[0021] like Figure 1 and Figure 2As shown, the excitation coil 4 is a plurality of excitation coils with the same number of turns, size and winding direction to ensure the uniformity of the magnetic field; the current passed through the excitation coil 4 is of the same magnitude and direction to ensure that the magnetic field in the working gap of the magnetorheological fluid will not cancel each other out; multiple excitation coils 4 can be energized at the same time to generate a working magnetic field to reduce the current stabilization time of the excitation coil 4 and improve the response speed of the device; the housing 8 is a fixed magnetic conductive housing; the pump wheel 3 and the turbine 6 are fixedly connected by bolts, which is convenient for disassembly and installation; a sealing strip is provided at the junction of the pump wheel 3 and the turbine 6 rim to prevent the magnetorheological fluid 5 from flowing out during operation, with good sealing effect and improved reliability; the blades 11 are made of alloy material, which has the characteristics of lightweight and wear resistance; Protrusions are evenly spaced and arranged at intervals on both sides of the blade 11 to increase the contact surface between the blade 11 and the magnetorheological fluid 5, thereby increasing the driving force. The magnetorheological fluid 5 is used as the working fluid in the multi-excitation coil magnetorheological coupler, and its controllable power output characteristics are utilized to change the viscosity of the transmission medium by controlling the magnetic field. The magnetorheological fluid 5 pushes the blade 11 to control the power transmission, thereby reducing the instability phenomenon that occurs when the circulation is diverted, and the power output is controlled in real time according to the load demand, which can effectively control the torque fluctuation problem caused by the circulation diversion and adjust the output torque as needed. The fixed magnetic conductive shell (i.e., the yoke) part is omitted in the multi-excitation coil magnetorheological coupler to reduce the hysteresis and eddy current phenomena in the magnetic circuit and improve the magnetic field response speed.

[0022] The working principle of this multi-excitation coil magnetorheological coupler is as follows: When the power machine drives the impeller 3 of the multi-excitation coil magnetorheological coupler to rotate through the input shaft 1, the magnetorheological fluid 5 filled in the working chamber of the coupler is subjected to the dual effects of centrifugal force and blades 11, and is accelerated and pressurized from the inlet of the impeller 3 with a smaller radius to the outlet of the impeller 3 with a larger radius. At the same time, the momentum of the liquid is increased, that is, the impeller 3 converts the mechanical energy input by the power machine into liquid kinetic energy; when the working liquid with liquid kinetic energy rushes from the outlet of the impeller 3 to the turbine 6 on the opposite side, the liquid flow impacts the blades 11 of the turbine 6 to rotate in the same direction as the impeller 3, thereby converting the liquid kinetic energy into mechanical energy, driving the turbine 6 to rotate and driving the working machine to do work; when the input shaft 1 drives the impeller 3 to rotate, the viscosity and transmission torque of the magnetorheological fluid 5 can be adjusted by changing the current intensity of the excitation coil 4.

[0023] In summary, the multi-excitation coil magnetorheological coupler generates a working magnetic field by simultaneously energizing multiple excitation coils 4, which effectively reduces the current stabilization time of the excitation coil 4 and the device has a fast response speed; the viscosity of the transmission medium is changed by controlling the magnetic field, and the blades 11 are pushed by the magnetorheological fluid 5 to control the power transmission, thereby reducing the instability phenomenon that occurs when the circulation is diverted, and the power output is controlled in real time according to the load demand. The device does not have the fixed magnetic conductive shell (i.e., the yoke) part of the traditional magnetorheological clutch, and the entire magnetic circuit part basically does not have hysteresis and eddy current phenomena. The magnetorheological fluid working gap magnetic field response speed is very fast, which can better meet the needs of high-frequency regulation of power transmission.

[0024] It is to be understood that the present invention is described by some embodiments, and it is known to those skilled in the art that various changes or equivalent substitutions may be made to these features and embodiments without departing from the spirit and scope of the present invention. In addition, under the teachings of the present invention, these features and embodiments may be modified to adapt to specific circumstances and materials without departing from the scope of the present invention. Therefore, the present invention is not limited by the specific embodiments disclosed herein, and all embodiments falling within the scope of the claims of this application are within the scope of protection of the present invention.

Claims

1. A multi-excitation coil magnetorheological coupler, characterized in that: It includes a stationary excitation coil assembly and a rotating transmission assembly disposed inside the stationary excitation coil assembly; The stationary excitation coil assembly is composed of excitation coils (4) arranged in parallel; The rotary transmission assembly includes a driving rotary assembly and a driven rotary assembly; The active rotating assembly is composed of an input shaft (1), a magnetically conductive left side plate (2), a pump wheel (3), a bearing (7), a housing (8), and a magnetically conductive right side plate (9), which are fixedly connected in sequence; The driven rotating assembly is composed of a turbine (6) fixedly connected to an output shaft (10) via a bearing (7); The pump wheel (3) and the turbine wheel (6) are detachably closed, and a sealed cavity is formed inside, and the cavity is filled with magnetorheological fluid (5); The pump wheel (3) and the turbine wheel (6) are arranged symmetrically, and blades (11) are provided inside each of them; A plurality of blades (11) are evenly spaced and arranged at intervals, a blade cavity is formed between two adjacent blades (11), the blade cavity gradually increases from the inner diameter to the outer diameter, and the blades (11) are all inclined in the same direction at 0°-10°.

2. The multi-excitation coil magnetorheological coupler according to claim 1, characterized in that: The excitation coil (4) is composed of a plurality of excitation coils having the same number of turns, size and winding direction.

3. The multi-excitation coil magnetorheological coupler according to claim 1, characterized in that: The current flowing into the excitation coil (4) has the same magnitude and direction.

4. The multi-excitation coil magnetorheological coupler according to claim 1, characterized in that: The housing (8) is a fixed magnetically conductive housing.

5. The multi-excitation coil magnetorheological coupler according to claim 1, characterized in that: The pump wheel (3) and the turbine wheel (6) are fixedly connected by bolts.

6. The multi-excitation coil magnetorheological coupler according to claim 1, characterized in that: A sealing strip is provided at the junction of the pump wheel (3) and the turbine wheel (6).

7. The multi-excitation coil magnetorheological coupler according to claim 1, characterized in that: The blades (11) are made of alloy material.

8. The multi-excitation coil magnetorheological coupler according to claim 1, characterized in that: Both sides of the blade (11) are provided with convex bodies evenly spaced at intervals.

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