Electric slewing mechanism with magnetorheological damper and control method of electric slewing mechanism

Abstract

The invention provides an electric slewing mechanism with a magneto-rheological damper and a control method thereof.The electric slewing mechanism comprises a motor, the motor is provided with a first end and a second end, the magneto-rheological damper is installed at the first end, a slewing speed reducer is installed at the second end, the motor is used for driving a rotary table to rotate, and the magneto-rheological damper is used for providing controllable braking torque; the first end of the rotary speed reducer is the input end of the motor, and the second end of the rotary speed reducer is the output end of the motor; a speed feedback system integrated to a motor controller is arranged on the periphery of the motor and used for controlling the magnitude of the input current of the magneto-rheological damper. According to the electric slewing mechanism with the magnetorheological damper and the control method of the electric slewing mechanism, the working current is linearly controlled through the speed feedback system, so that the intensity of an external magnetic field of the magnetorheological fluid is adjusted, the rheological property of the magnetorheological fluid is rapidly and continuously changed in a pulse-free mode, the braking torque with the controllable magnitude is provided for the input end of the motor shaft, and the braking torque is controlled. The purpose of repeatedly controlling the braking torque of the magnetorheological damper in real time is achieved.

Description

Technical Field

[0001] The invention relates to the technical field of slewing mechanisms, and in particular to an electric slewing mechanism with a magnetorheological damper and a control method thereof. Background Art

[0002] The slewing mechanism of existing engineering machinery is generally composed of a slewing motor, a slewing reducer, a slewing bearing, and a hydraulic circuit. Its transmission method is generally achieved by mechanical connection and hydraulic drive. However, due to the complexity of the hydraulic circuit and the hydraulic hysteresis problem, the braking torque is transmitted slowly, and braking delay is prone to occur, making it difficult to accurately control the braking torque. At the same time, the flow pulsation of the hydraulic brake system will cause pressure pulsation, resulting in vibration and noise in some hydraulic components. In addition, due to the structural characteristics of each actuator in the hydraulic circuit, it is difficult to integrate it with the electronic control system.

[0003] However, when the turntable reaches the stop position, if the slewing motor is replaced by an electric motor, due to the rotational inertia of the bucket load and the characteristics of the speed control mode, relying solely on the motor to complete the slewing braking will cause the turntable to swing back and forth at the stop position, causing great inconvenience to the operator's slewing operation.

[0004] Therefore, it is necessary to provide an electric slewing mechanism with a magnetorheological damper and a control method thereof to solve the above problems. Summary of the invention

[0005] The object of the present invention is to provide an electric rotary mechanism with a magnetorheological damper and a control method thereof, wherein the working current is linearly controlled by a speed feedback system to adjust the strength of the external magnetic field of the magnetorheological fluid, thereby rapidly, continuously and pulse-free changing the rheological characteristics of the magnetorheological fluid, providing a controllable braking torque for the input end of the motor shaft, and ultimately achieving the purpose of real-time and repeated control of the braking torque of the magnetorheological damper.

[0006] An embodiment of the present invention provides an electric slewing mechanism with a magnetorheological damper, comprising:

[0007] A motor having a first end and a second end, wherein a magnetorheological damper is installed at the first end, and a rotary reducer is installed at the second end, wherein the motor is used to drive the turntable to rotate, the magnetorheological damper is used to provide a controllable dynamic torque, and the rotary reducer is used to reduce speed and increase torque, wherein the first end is an input end of the motor, and the second end is an output end of the motor;

[0008] The motor is provided with a speed feedback system integrated in the motor controller, and the speed feedback system is used to control the input current of the magnetorheological damper;

[0009] It also includes a slewing bearing and a slewing flange. The slewing bearing is used for supporting, and the slewing flange is used for connecting the magnetorheological damper and the turntable.

[0010] Preferably, the magnetorheological damper includes a rotating shaft, a transparent cover, a shell, an excitation coil, a magnetic isolation ring, a magnetic conductive sheet, a bearing seat, a bearing, a blind cover, an adjustment gasket, a flat key, a side excitation coil, a gear-type brake disc, an O-ring, a side magnetic isolation ring, a bushing and an oil seal felt ring. The magnetic conductive sheet, magnetic isolation ring and side magnetic isolation ring are used for conducting or isolating magnetism, guiding the magnetic lines of force along the direction of the magnetic circuit through the working gap of the magnetorheological damper and limiting the magnetic lines of force from gathering in the non-working gap.

[0011] Preferably, the slewing flange, the blind cover and the bearing seat are all connected by bolts; the bearing seat and the housing are connected by bolts; the transparent cover and the bearing seat are connected by bolts; and the rotating shaft and the motor are connected by splines.

[0012] Preferably, the gear-type brake disc is axially positioned and circumferentially positioned by a shaft shoulder and a flat key respectively; the inner ring of the bearing is axially positioned by the shaft sleeve, and the inner ring of the bearing is axially fixed by the blind cover or the transparent cover; the magnetic ring is axially positioned by the shaft sleeve or the shaft shoulder; and the housing is axially positioned by the shaft sleeve.

[0013] Preferably, an O-ring and an oil seal felt ring are respectively installed between the magnetic conductive sheet and the magnetic isolation ring, between the magnetic conductive sheet and the housing, and between the transparent cover and the rotating shaft.

[0014] Preferably, an interference fit is adopted between the inner ring of the bearing and the rotating shaft.

[0015] Preferably, the magnetorheological damper disc type is any one of a gear type, a cylindrical type, a disc type or a cylinder type.

[0016] Preferably, the excitation coil winding is any one of the internal, external, and side-mounted types or a combination thereof.

[0017] Preferably, the magnetorheological damper is installed at the first end or the second end of the motor, or the magnetorheological damper is assembled with the rotary reducer to form an epicyclic gear train.

[0018] An embodiment of the present invention also provides a control method of an electric slewing mechanism with a magnetorheological damper using any one of the above, comprising:

[0019] Step 1: The vehicle controller collects the rotation signal from the driver moving the joystick left and right;

[0020] Step 2: After receiving the rotation signal, the vehicle controller analyzes and processes the signal to generate specific control instructions;

[0021] Step 3: The processed control command is transmitted to the motor controller via the CAN bus, and the motor controller adjusts the current and phase of the motor according to the command, thereby controlling the running state of the motor;

[0022] Step 4: The motor controller applies a sinusoidal AC voltage to the excitation winding of the rotary transformer. As the salient pole rotor rotates, the mutual inductance between the output winding and the excitation winding changes regularly, inducing corresponding sine and cosine signals. At the same time, the corresponding sine and cosine signals are transmitted to the motor controller, and the rotor speed is analyzed by its decoding circuit.

[0023] Step 5: After the motor controller obtains the rotor speed, it calculates the required excitation coil current Im according to the preset control logic and algorithm, thereby adjusting the braking torque at the motor input end in real time.

[0024] Compared with the prior art, the technical solution of the embodiment of the present invention has at least the following beneficial effects:

[0025] The present invention provides an electric slewing mechanism with a magnetorheological damper and a control method thereof, wherein the electric slewing mechanism comprises: a motor having a first end and a second end, wherein the first end is provided with a magnetorheological damper, and the second end is provided with a slewing reducer, wherein the motor is used to drive a turntable to slew, the magnetorheological damper is used to provide a controllable dynamic torque, and the slewing reducer is used to reduce speed and increase torque, wherein the first end is the input end of the motor, and the second end is the output end of the motor; a speed feedback system integrated in a motor controller is arranged on the peripheral side of the motor, and the speed feedback system is used to control the magnitude of the input current of the magnetorheological damper; the motor also comprises a slewing bearing and a slewing flange, wherein the slewing bearing is used to play a supporting role, and the slewing flange is used to connect the magnetorheological damper and the turntable, and the reciprocating swing problem of the turntable caused by the load rotation inertia and the speed control mode characteristics of the motor during braking can be effectively avoided by installing the magnetorheological damper;

[0026] Furthermore, the magnetorheological effect has a response speed of milliseconds, which is different from the hydraulic rotary mechanism, which needs the transmission module to transmit the braking torque step by step, thus shortening the braking time;

[0027] Furthermore, compared with conventional hydraulic swing brakes, magnetorheological fluids have a wide operating yield stress and temperature adjustment range, which can enhance the controllability of the braking torque;

[0028] Furthermore, magnetorheological fluid is used instead of hydraulic pressure to simplify the overall structure of the slewing mechanism so that it can be integrated with the electronic control system;

[0029] Furthermore, the rheological properties of the magnetorheological fluid are continuously controlled by an applied magnetic field, which helps to reduce the vibration and noise generated during the braking process, thereby improving braking stability;

[0030] Furthermore, magnetorheological fluid can generate a larger yield stress under a weaker magnetic field, which is beneficial to reducing braking energy consumption. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 is a structural schematic diagram of an electric rotary mechanism with a magnetorheological damper in an embodiment of the present invention;

[0032] Figure 2 is a schematic diagram of a top view of an electric rotary mechanism with a magnetorheological damper in an embodiment of the present invention;

[0033] Figure 3 1 is a schematic structural diagram of a magnetorheological damper of an electric rotary mechanism having a magnetorheological damper in an embodiment of the present invention;

[0034] Figure 4 is a schematic cross-sectional structural diagram of a magnetorheological damper of an electric rotary mechanism having a magnetorheological damper in an embodiment of the present invention;

[0035] Figure 5 The figure is a schematic diagram of the working principle of an electric rotary mechanism with a magnetorheological damper in an embodiment of the present invention.

[0036] Description of reference numerals:

[0037] 1. Speed ​​feedback system; 2. Magnetorheological damper; 3. Motor; 4. Rotary reducer;

[0038] 5. Slewing bearing; 6. Slewing flange;

[0039] 2-1, rotating shaft; 2-2—transparent cover; 2-3, housing; 2-4, excitation coil; 2-5, magnetic isolation ring; 2-6, magnetic conductive sheet; 2-7, bearing seat; 2-8, bearing; 2-9, blind cover; 2-10, adjustment gasket;

[0040] 2-11, flat key; 2-12, side excitation coil; 2-13, gear-type brake disc; 2-14, O-ring; 2-15, side magnetic isolation ring; 2-16, shaft sleeve; 2-17, oil seal felt ring. DETAILED DESCRIPTION

[0041] In order to make the purpose, features and beneficial effects of the present invention more obvious and understandable, the specific embodiments of the present invention are described in detail below in conjunction with the accompanying drawings. It is understood that the specific embodiments described below are only used to explain the present invention, rather than to limit the present invention. In addition, the same or similar reference numerals may be used in the figures to refer to the same or similar elements in different embodiments, and the description of the same or similar elements in different embodiments and the description of the prior art elements, features, effects, etc. may be omitted.

[0042] Figure 1 is a structural schematic diagram of an electric rotary mechanism in an embodiment of the present invention; Figure 2 is a schematic diagram of a top view of an electric rotary mechanism in an embodiment of the present invention; Figure 3 is a schematic structural diagram of a magnetorheological damper of an electric slewing mechanism in an embodiment of the present invention; Figure 4 is a schematic cross-sectional structural diagram of a magnetorheological damper of an electric rotary mechanism in an embodiment of the present invention; Figure 5 It is a schematic diagram of the working principle of an electric rotary mechanism in an embodiment of the present invention.

[0043] Now refer to Figures 1 to 5 The embodiment of the present invention provides an electric rotary mechanism with a magnetorheological damper and a control method thereof, which linearly controls the working current through a speed feedback system to adjust the strength of the external magnetic field of the magnetorheological fluid, thereby quickly, continuously and pulse-free changing the rheological characteristics of the magnetorheological fluid, providing a controllable braking torque for the input end of the motor shaft, and ultimately achieving the purpose of real-time and repeated control of the braking torque of the magnetorheological damper.

[0044] An electric slewing mechanism with a magnetorheological damper 2 provided in an embodiment of the present invention comprises:

[0045] The motor 3 has a first end and a second end, the first end is equipped with a magnetorheological damper 2, the second end is equipped with a rotary reducer 4, the motor 3 is used to drive the turntable to rotate, the magnetorheological damper 2 is used to provide a controllable dynamic torque, the rotary reducer 4 is used to reduce speed and increase torque, the first end is the input end of the motor 3, and the second end is the output end of the motor 3;

[0046] The motor 3 is provided with a speed feedback system 1 integrated in the motor controller, and the speed feedback system 1 is used to control the input current of the magnetorheological damper 2;

[0047] It also includes a slewing bearing 5 and a slewing flange 6. The slewing bearing 5 is used for supporting, and the slewing flange 6 is used for connecting the magnetorheological damper 2 and the turntable.

[0048] Specifically, the motor controller is a MCU (Microcontroller Unit).

[0049] In a specific implementation, the magnetorheological damper 2 includes a rotating shaft 2-1, a transparent cover 2-2, a shell 2-3, an excitation coil 2-4, a magnetic isolation ring 2-5, a magnetic conductive sheet 2-6, a bearing seat 2-7, a bearing 2-8, a cover 2-9, an adjustment gasket 2-10, a flat key 2-11, a side excitation coil 2-12, a gear-type brake disc 2-13, an O-ring 2-14, a side magnetic isolation ring 2-15, a shaft sleeve 2-16 and an oil seal felt ring 2-17. The magnetic conductive sheet 2-6, the magnetic isolation ring 2-5 and the side magnetic isolation ring 2-15 are used for magnetic conduction or magnetic isolation, guiding the magnetic lines of force along the direction of the magnetic circuit through the working gap of the magnetorheological damper 2 and limiting the magnetic lines of force from gathering in the non-working gap.

[0050] In a specific implementation, the swivel flange 6, the cover 2-9 and the bearing seat 2-7 are all connected by bolts; the bearing seat 2-7 and the housing 2-3 are connected by bolts; the transparent cover 2-2 and the bearing seat 2-7 are connected by bolts; the rotating shaft 2-1 and the motor 3 are connected by splines.

[0051] In a specific implementation, the gear-type brake disc 2-13 is axially positioned and circumferentially positioned by the shaft shoulder and the flat key 2-11 respectively; the inner ring of the bearing 2-8 is axially positioned by the shaft sleeve 2-16, and the inner ring of the bearing 2-8 is axially fixed by the cover 2-9 or the transparent cover 2-2; the magnetic ring is axially positioned by the shaft sleeve 2-16 or the shaft shoulder; the housing 2-3 is axially positioned by the shaft sleeve 2-16.

[0052] The magnetic conductive sheet 2-6, the magnetic isolation ring 2-5 and the side magnetic isolation ring 2-15 are used for magnetic conduction or magnetic isolation, guiding the magnetic lines of force along the magnetic circuit direction through the working gap of the magnetorheological damper and limiting the magnetic lines of force from gathering in the non-working gap. The inner ring of the side magnetic isolation ring 2-15 is interference fit with the magnetic conductive sheet 2-6, the outer ring of the side magnetic isolation ring 2-15 is interference fit with the magnetic conductive sheet 2-6, and the side excitation coil 2-12 is tightly wound around the outer ring of the magnetic conductive sheet 2-6.

[0053] In a specific implementation, an O-ring 2-14 and an oil seal felt ring 2-17 are respectively installed between the magnetic conductive sheet 2-6 and the magnetic isolation ring 2-5, between the magnetic conductive sheet 2-6 and the housing 2-3, and between the transparent cover 2-2 and the rotating shaft 2-1.

[0054] In a specific implementation, an interference fit is adopted between the inner ring of the bearing 2-8 and the rotating shaft 2-1.

[0055] In a specific implementation, the disk type of the magnetorheological damper 2 is any one of a gear type, a cylindrical type, a disk type or a cylinder type.

[0056] In a specific implementation, the windings of the excitation coils 2 - 4 are any one of the internal, external, and side-mounted types or a combination thereof.

[0057] In a specific implementation, the magnetorheological damper 2 is installed at the first end or the second end of the motor 3, or the magnetorheological damper 2 is assembled with the rotary reducer 4 to form an epicyclic gear train.

[0058] The embodiment of the present invention also provides a control method of an electric slewing mechanism having a magnetorheological damper 2 using any one of the above items, comprising:

[0059] Step 1: The vehicle controller collects the rotation signal from the driver moving the joystick left and right;

[0060] Step 2: After receiving the rotation signal, the vehicle controller analyzes and processes the signal to generate specific control instructions;

[0061] Step 3: The processed control command is transmitted to the motor controller via the CAN bus, and the motor controller adjusts the current and phase of the motor according to the command, thereby controlling the running state of the motor;

[0062] Step 4: The motor controller applies a sinusoidal AC voltage to the excitation winding of the rotary transformer. As the salient pole rotor rotates, the mutual inductance between the output winding and the excitation winding changes regularly, inducing corresponding sine and cosine signals. At the same time, the corresponding sine and cosine signals are transmitted to the motor controller, and the rotor speed is analyzed by its decoding circuit.

[0063] Step 5: After the motor controller obtains the rotor speed, it calculates the required excitation coil current Im according to the preset control logic and algorithm, thereby adjusting the braking torque at the motor input end in real time.

[0064] Specifically, Im=f(n) indicates that the input current Im of the magnetorheological damper is a function of the motor output speed n. The speed n of the feedback signal is obtained in the following way: the decoding chip of the motor controller can accurately determine the rotor's rotation angle (i.e., its instantaneous position), speed, and direction according to the induced voltage waveform (sine and cosine) on the output winding of the rotary transformer. P / N indicates the wiring method (N) of the positive (P) and negative poles in the circuit.

[0065] An embodiment of the present invention provides an electric slewing mechanism with a magnetorheological damper and a control method thereof, wherein the electric slewing mechanism comprises: a motor having a first end and a second end, wherein the first end is provided with a magnetorheological damper, and the second end is provided with a slewing reducer, wherein the motor is used to drive a turntable to slew, the magnetorheological damper is used to provide a controllable dynamic torque, and the slewing reducer is used to reduce speed and increase torque, wherein the first end is the input end of the motor, and the second end is the output end of the motor; a speed feedback system integrated in a motor controller is arranged on the peripheral side of the motor, and the speed feedback system is used to control the magnitude of the input current of the magnetorheological damper; the motor also comprises a slewing bearing and a slewing flange, wherein the slewing bearing is used to play a supporting role, and the slewing flange is used to connect the magnetorheological damper and the turntable, and the reciprocating swing problem of the turntable caused by the load rotation inertia and the speed control mode characteristics of the motor during braking can be effectively avoided by installing the magnetorheological damper;

[0066] Furthermore, the magnetorheological effect has a response speed of milliseconds, which is different from the hydraulic rotary mechanism, which needs the transmission module to transmit the braking torque step by step, thus shortening the braking time;

[0067] Furthermore, compared with conventional hydraulic swing brakes, magnetorheological fluids have a wide operating yield stress and temperature adjustment range, which can enhance the controllability of the braking torque;

[0068] Furthermore, magnetorheological fluid is used instead of hydraulic pressure to simplify the overall structure of the slewing mechanism so that it can be integrated with the electronic control system;

[0069] Furthermore, the rheological properties of the magnetorheological fluid are continuously controlled by an applied magnetic field, which helps to reduce the vibration and noise generated during the braking process, thereby improving braking stability;

[0070] Furthermore, magnetorheological fluid can generate a larger yield stress under a weaker magnetic field, which is beneficial to reducing braking energy consumption.

[0071] Although specific embodiments have been described above, these embodiments are not intended to limit the scope of the present disclosure, even when only a single embodiment is described with respect to specific features. The feature examples provided in the present disclosure are intended to be illustrative rather than limiting, unless otherwise stated. In specific implementations, the technical features of one or more dependent claims may be combined with the technical features of the independent claims, based on actual needs and where technically feasible, and the technical features from the corresponding independent claims may be combined in any appropriate manner rather than just by the specific combinations listed in the claims.

[0072] Although the present invention is disclosed as above, the present invention is not limited thereto. Any person skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the scope defined by the claims.

Claims

1. An electric slewing mechanism with a magnetorheological damper, characterized in that: include: A motor having a first end and a second end, wherein a magnetorheological damper is installed at the first end, and a rotary reducer is installed at the second end, wherein the motor is used to drive the turntable to rotate, the magnetorheological damper is used to provide a controllable dynamic torque, and the rotary reducer is used to reduce speed and increase torque, wherein the first end is an input end of the motor, and the second end is an output end of the motor; The motor is provided with a speed feedback system integrated in the motor controller, and the speed feedback system is used to control the input current of the magnetorheological damper; It also includes a slewing bearing and a slewing flange. The slewing bearing is used for supporting, and the slewing flange is used for connecting the magnetorheological damper and the turntable.

2. The electric rotary mechanism with a magnetorheological damper according to claim 1, characterized in that: The magnetorheological damper includes a rotating shaft, a transparent cover, a shell, an excitation coil, a magnetic isolation ring, a magnetic conductive sheet, a bearing seat, a bearing, a cover, an adjustment gasket, a flat key, a side excitation coil, a gear-type brake disc, an O-ring, a side magnetic isolation ring, a shaft sleeve and an oil seal felt ring. The magnetic conductive sheet, the magnetic isolation ring and the side magnetic isolation ring are used for conducting or isolating magnetism, guiding the magnetic lines of force along the direction of the magnetic circuit through the working gap of the magnetorheological damper and limiting the magnetic lines of force from gathering in the non-working gap.

3. The electric rotary mechanism with a magnetorheological damper according to claim 2, characterized in that: The slewing flange, the blind cover and the bearing seat are all connected by bolts; the bearing seat and the housing are connected by bolts; the transparent cover and the bearing seat are connected by bolts; and the rotating shaft and the motor are connected by splines.

4. The electric rotary mechanism with a magnetorheological damper according to claim 2, characterized in that: The gear-type brake disc is axially positioned and circumferentially positioned by a shaft shoulder and a flat key respectively; the inner ring of the bearing is axially positioned by the shaft sleeve, and the inner ring of the bearing is axially fixed by the blind cover or the transparent cover; the magnetic ring is axially positioned by the shaft sleeve or the shaft shoulder; and the housing is axially positioned by the shaft sleeve.

5. The electric rotary mechanism with a magnetorheological damper according to claim 2, characterized in that: An O-type sealing ring and an oil seal felt ring are respectively arranged between the magnetic conductive sheet and the magnetic isolation ring, between the magnetic conductive sheet and the shell, and between the transparent cover and the rotating shaft.

6. The electric rotary mechanism with a magnetorheological damper according to claim 2, characterized in that: An interference fit is adopted between the inner ring of the bearing and the rotating shaft.

7. The electric rotary mechanism with a magnetorheological damper according to claim 1, characterized in that: The magnetorheological damper disc type is any one of a gear type, a cylindrical type, a disc type or a cylinder type.

8. The electric rotary mechanism with a magnetorheological damper according to claim 2, characterized in that: The excitation coil winding is any one of the internal, external, and side-mounted types or a combination thereof.

9. The electric rotary mechanism with a magnetorheological damper according to claim 1, characterized in that: The magnetorheological damper is installed at the first end or the second end of the motor, or the magnetorheological damper is assembled with the rotary reducer to form an epicyclic gear train.

10. A control method for an electric slewing mechanism with a magnetorheological damper according to any one of claims 1 to 9, characterized in that: include: Step 1: The vehicle controller collects the rotation signal from the driver moving the joystick left and right; Step 2: After receiving the rotation signal, the vehicle controller analyzes and processes the signal to generate specific control instructions; Step 3: The processed control command is transmitted to the motor controller via the CAN bus, and the motor controller adjusts the current and phase of the motor according to the command, thereby controlling the running state of the motor; Step 4: The motor controller applies a sinusoidal AC voltage to the excitation winding of the rotary transformer. As the salient pole rotor rotates, the mutual inductance between the output winding and the excitation winding changes regularly, inducing corresponding sine and cosine signals. At the same time, the corresponding sine and cosine signals are transmitted to the motor controller, and the rotor speed is analyzed by its decoding circuit. Step 5: After the motor controller obtains the rotor speed, it calculates the required excitation coil current Im according to the preset control logic and algorithm, thereby adjusting the braking torque at the motor input end in real time.

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