Non-contact linear actuator with self-locking performance

Abstract

The invention provides a self-locking non-contact linear actuator which comprises a rotor assembly and a stator assembly, the rotor assembly is rotatably arranged in an inner cavity of the stator assembly, and the stator assembly comprises a first magnetic shoe, a second magnetic shoe and a stator shell; the rotor assembly comprises a hollow shaft and a silicon steel sheet, and the silicon steel sheet sleeves the outer wall of the hollow shaft; the first magnetic shoe and the second magnetic shoe are arranged on the inner wall of the stator shell and surround the silicon steel sheet, and a notch with a downward opening is formed in the lower portion of the first magnetic shoe. In the four magnetic shoes, one magnetic shoe is designed into an inverted V-shaped groove, and the other three magnetic shoes are kept complete, so that the magnetic field intensity distribution is non-uniform, the holding force of large current is reduced, and the self-locking property is further realized. The electronic control linear actuator is applied to the position signal feedback technology of the automobile, the retention force can be improved, the heating of the linear actuator is reduced, and the efficiency of the actuator is improved.

Description

Technical Field

[0001] The invention belongs to the technical field of diesel engine EGR, in particular to a non-contact linear actuator with self-locking function. Background Art

[0002] In the prior art, a power drive device for EGR using a linear actuator is used, such as a housing of an EGR valve for accurately detecting the opening degree disclosed in Chinese patent CN208310925U, in which an air inlet and an air outlet are provided on the housing, a motor is installed in the housing, a push rod is installed in the rotor of the motor, a piston is installed on the push rod, and the piston controls the opening and closing of the air inlet and the air outlet, and is characterized in that: a magnet is installed on the push rod, a Hall sensor is fixed in the housing, the Hall sensor senses the magnetic field of the magnet and transmits the signal to the circuit board as a control signal for starting and stopping the motor. Since a magnet is also installed on the push rod and a Hall sensor is fixed in the housing, the push rod drives the magnet to move while driving the piston to move up and down, so that the magnetic field strength sensed by the Hall sensor changes, so that the position of the push rod can be accurately judged according to the signal provided by the Hall sensor, thereby determining the opening degree of the piston to the air inlet and the air outlet. The above structure has the following disadvantages: the holding force of the driving motor is poor, and a large current needs to be maintained to maintain the holding force, the motor of the linear actuator itself generates heat, the execution efficiency of the linear actuator will be greatly reduced, and the service life of the linear actuator will be affected. Summary of the invention

[0003] The present invention provides a non-contact linear actuator with self-locking property. Among four magnetic tiles, one magnetic tile is designed with an inverted "V" groove, and the other three magnetic tiles remain intact, so that the magnetic field strength is unevenly distributed, the holding force of large current is reduced, and the self-locking property is achieved. The position signal feedback technology of the electric-controlled linear actuator applied to the automobile can improve the holding force, reduce the heat of the linear actuator itself, and improve the efficiency of the actuator.

[0004] To achieve the above-mentioned purpose, the present invention provides a non-contact linear actuator with self-locking properties, including a rotor assembly and a stator assembly, wherein the rotor assembly is rotatably arranged in the inner cavity of the stator assembly, and the stator assembly includes a first magnetic tile, a second magnetic tile and a stator housing; the rotor assembly includes a hollow shaft and a silicon steel sheet, and the silicon steel sheet is arranged on the outer wall of the hollow shaft; the first magnetic tile and the second magnetic tile are both arranged on the inner wall of the stator housing and are arranged around the outside of the silicon steel sheet, and a notch opening downward is arranged at the lower part of the first magnetic tile.

[0005] The present invention designs a magnetic tile with a downward notch while keeping other tiles intact, thereby realizing a structure with uneven distribution of magnetic field strength, reducing the high current operation of the motor, having good holding force, achieving self-locking, and also reducing contact friction between components.

[0006] Preferably, the first magnetic tile is set to 1, the second magnetic tile is set to 3, and the first magnetic tile and the second magnetic tile are evenly spaced and arranged on the inner wall of the stator housing. By making one magnetic tile into a notched groove design, the other three magnetic tiles remain intact, and the four magnetic tiles are evenly distributed at an angle of 90° around the circumference, the structure is simple, easy to position and install, and the cost is low.

[0007] Preferably, the notch of the first magnetic tile is configured as an inverted V-shaped structure, which is simple in structure and easy to process and manufacture.

[0008] Preferably, the height of the first magnetic tile is 20-22 mm, the width of the first magnetic tile is 19-21 mm, the angle of the V-shaped structure is 55-65°, and the depth of the V-shaped structure is 4-7 mm. The structural parameters of the V-shaped structure can maintain the structural strength of the first magnetic tile and make the magnetic field strength unevenly distributed, so as to facilitate axial adsorption of the rotor assembly.

[0009] Preferably, the first magnetic tile, the second magnetic tile and the silicon steel sheet have the same height, and the lower end faces of the first magnetic tile and the second magnetic tile are both set at a height lower than the lower end face of the silicon steel sheet. In the prior art, the normal rotor assembly is located at the center of the magnetic tile, that is, the lower end face of the magnetic tile is flush with the lower end face of the silicon steel sheet. The design of the magnetic tile of the present invention is lower than the silicon steel sheet, in order to generate a rotating torque when the magnet is powered on and have relative vibration resistance, reduce vibration, and the actuator works smoothly and the control is precise.

[0010] Preferably, the height difference between the lower end surface of the first magnetic tile and the lower end surface of the silicon steel sheet is 1 to 1.5 mm. The design that the lower end surface of the first magnetic tile (201) is 1 to 1.5 mm lower than the bottom of the silicon steel sheet ensures that the magnet generates a rotation torque when powered on and has relative vibration resistance.

[0011] Specifically, the present invention further comprises an output shaft, the outer wall of the output shaft is threadedly connected to the inner wall of the hollow shaft. The present invention further comprises a large ball bearing, one end of the large ball bearing is connected to the lower part of the stator housing and the other end is matched with the lower part of the hollow shaft. The large ball bearing is used to support the stable rotation of the hollow shaft, improve working stability, reduce friction, and increase service life.

[0012] Compared with the prior art, the present invention has the following beneficial effects:

[0013] The present invention only sets one magnetic tile into an inverted "V"-shaped groove design, and the other three magnetic tiles remain intact, so that the magnetic field strength is unevenly distributed, reducing the holding force of large currents, and the rotor is subjected to uneven forces, thereby achieving self-locking, while also reducing contact friction between components and reducing the heat generation of the linear actuator itself.

[0014] The present invention adopts a design in which the magnetic shoe is lower than the silicon steel sheet. When power is turned on, the magnet generates a rotation torque and has relative vibration resistance, thereby reducing vibration, ensuring that the actuator works smoothly and is precisely controlled. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 It is a structural schematic diagram of a non-contact linear actuator with self-locking property described in the present invention.

[0016] Figure 2 and Figure 3 This is a positional relationship diagram of the first magnetic tile, the second magnetic tile and the silicon steel sheet of the present invention.

[0017] Figure 4 It is a structural diagram of the first magnetic tile of the present invention.

[0018] Figure 5 It is a comparison diagram of the change of magnetic field intensity in the present invention and the prior art.

[0019] Figure 6 It is a thrust curve diagram of the present invention.

[0020] Figure 7 It is a thrust curve diagram of the prior art.

[0021] In the figure: 1-rotor assembly, 101-hollow shaft, 102-silicon steel sheet, 2-stator assembly, 201-first magnetic tile, 202-second magnetic tile, 203-stator housing, 3-output shaft, 4-large ball bearing. DETAILED DESCRIPTION

[0022] The present invention will be further described below in conjunction with the accompanying drawings and specific implementation methods. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute improper limitations on the present invention.

[0023] In the description of the present invention, it is necessary to understand that the terms "left", "right", "up", "down", "front", "back", etc. indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or structure referred to must have a specific direction, be constructed and operate in a specific direction, and therefore cannot be understood as a limitation on the present invention.

[0024] Embodiment 1:

[0025] A non-contact linear actuator with self-locking function is used in the position signal feedback technology of the electronically controlled linear actuator of the automobile, such as the EGR valve actuator. Through the rotation of the rotor assembly, the output shaft 3 of the motor performs linear displacement motion, and then the output shaft 3 acts on the valve stem to realize the opening and closing of the valve plate.

[0026] like Figures 1 to 4As shown, the non-contact linear actuator with self-locking properties described in this embodiment includes a rotor assembly 1 and a stator assembly 2, wherein the rotor assembly 1 is rotatably arranged in the inner cavity of the stator assembly 2, and the stator assembly 2 includes a first magnetic tile 201, a second magnetic tile 202 and a stator housing 203; the rotor assembly 1 includes a hollow shaft 101 and a silicon steel sheet 102, and the silicon steel sheet 102 is arranged on the outer wall of the hollow shaft 101; the first magnetic tile 201 and the second magnetic tile 202 are both arranged on the inner wall of the stator housing 203 and are arranged around the outside of the silicon steel sheet 102, and the lower part of the first magnetic tile 201 is provided with a notch 204 opening downward.

[0027] This embodiment adopts an inverted "V"-shaped groove design for a magnetic tile, while the other tiles remain intact, achieving a structure with uneven distribution of magnetic field strength, reducing the high current operation of the motor, having good holding force, achieving self-locking, and also reducing contact friction between components.

[0028] Embodiment 2:

[0029] like Figures 1 to 4 As shown, a non-contact linear actuator with self-locking property includes a rotor assembly 1 and a stator assembly 2, wherein the rotor assembly 1 is rotatably arranged in the inner cavity of the stator assembly 2, and the stator assembly 2 includes a first magnetic tile 201, a second magnetic tile 202 and a stator housing 203; the rotor assembly 1 includes a hollow shaft 101 and a silicon steel sheet 102, and the silicon steel sheet 102 is arranged on the outer wall of the hollow shaft 101; the first magnetic tile 201 and the second magnetic tile 202 are both arranged on the inner wall of the stator housing 203 and are arranged around the outside of the silicon steel sheet 102, and the lower part of the first magnetic tile 201 is provided with a notch 204 opening downward.

[0030] like Figure 3 As shown, in this embodiment, the number of the first magnetic tile 201 is 1, the number of the second magnetic tile 202 is 3, the first magnetic tile 201 and the second magnetic tile 202 are evenly spaced on the inner wall of the stator housing 203, and the four magnetic tiles are evenly distributed at an angle of 90° around the circumference.

[0031] like Figure 4 As shown, in this embodiment, the notch 204 is constructed as an inverted V-shaped structure, with the V-shaped opening facing downward, and the V-shaped opening is arranged at the center position of the axis of the lower part of the first magnetic tile 201.

[0032] like Figure 4 As shown, in this embodiment, the height of the first magnetic tile 201 is 20-22 mm, the width of the first magnetic tile 201 is 19-21 mm, the angle of the V-shaped structure is 55-65°, and the depth of the V-shaped structure is 4-7 mm. The first magnetic tile 201 is constructed in a tile shape.

[0033] like Figure 2 As shown, in this embodiment, the first magnetic tile 201, the second magnetic tile 202 and the silicon steel sheet 102 have the same height, and the lower end surfaces of the first magnetic tile 201 and the second magnetic tile 202 are arranged at a height lower than the lower end surface of the silicon steel sheet 102. The height difference between the lower end surface of the first magnetic tile 201 and the lower end surface of the silicon steel sheet 102 is 1 to 1.5 mm.

[0034] like Figure 1 As shown, in this embodiment, an output shaft 3 is also included, and the outer wall of the output shaft 3 is threadedly connected to the inner wall of the hollow shaft 101. In this embodiment, a large ball bearing 4 is also included, and one end of the large ball bearing 4 is connected to the lower part of the stator housing 203 and the other end is matched with the lower part of the hollow shaft 101. The large ball bearing 4 is used to support the stable rotation of the hollow shaft 101.

[0035] In this embodiment, only one magnetic tile is set to an inverted "V"-shaped groove design, and the other three magnetic tiles remain intact;

[0036] All magnetic tile structures in the prior art are the same;

[0037] The comparison of the magnetic field intensity changes of this embodiment and the prior art is as follows: Figure 5 As shown, it can be seen that in the solution without V-groove structure in the prior art, the magnetic field strength changes linearly with the angle.

[0038] In this embodiment, a "V"-shaped groove design is adopted, and the magnetic field strength changes with the angle, making the magnetic field strength unevenly distributed, reducing the holding force of large currents, and the rotor is subjected to uneven forces, thereby achieving self-locking, while also reducing contact friction between components and reducing the heat generation of the linear actuator itself.

[0039] The thrust curve without V-groove in the prior art is as follows Figure 7 As shown, it can be seen that its thrust is constant and it does not have self-locking ability;

[0040] The thrust curve of the V-groove in this embodiment is as follows: Figure 6 As shown in the figure, it can be seen that the thrust will have a trough, thus achieving self-locking, while also reducing the contact friction between components and reducing the heat of the linear actuator itself

[0041] This embodiment adopts a design in which the magnetic shoe is lower than the silicon steel sheet 102. When powered on, the magnet generates a rotational torque and has relative vibration resistance, thereby reducing vibration, allowing the actuator to operate smoothly and be precisely controlled.

Claims

1. A non-contact linear actuator with self-locking function, characterized in that The invention comprises a rotor assembly (1) and a stator assembly (2), wherein the rotor assembly (1) is rotatably arranged in the inner cavity of the stator assembly (2), and the stator assembly (2) comprises a first magnetic tile (201), a second magnetic tile (202) and a stator housing (203); the rotor assembly (1) comprises a hollow shaft (101) and a silicon steel sheet (102), and the silicon steel sheet (102) is arranged on the outer wall of the hollow shaft (101); the first magnetic tile (201) and the second magnetic tile (202) are both arranged on the inner wall of the stator housing (203) and are arranged around the outside of the silicon steel sheet (102), and the lower part of the first magnetic tile (201) is provided with a notch (204) opening downward.

2. A non-contact linear actuator with self-locking properties according to claim 1, characterized in that: The number of the first magnetic tile (201) is one, the number of the second magnetic tile (202) is three, and the first magnetic tile (201) and the second magnetic tile (202) are evenly spaced and arranged on the inner wall of the stator housing (203).

3. A non-contact linear actuator with self-locking properties according to claim 1, characterized in that: The notch (204) is configured as an inverted V-shaped structure.

4. A non-contact linear actuator with self-locking properties according to claim 3, characterized in that: The height of the first magnetic tile (201) is 20 to 22 mm, the width of the first magnetic tile (201) is 19 to 21 mm, the angle of the V-shaped structure is 55 to 65°, and the depth of the V-shaped structure is 4 to 7 mm.

5. The non-contact linear actuator with self-locking property according to claim 1, characterized in that: The first magnetic tile (201), the second magnetic tile (202) and the silicon steel sheet (102) have the same height, and the lower end surfaces of the first magnetic tile (201) and the second magnetic tile (202) are both arranged at a height lower than the lower end surface of the silicon steel sheet (102).

6. A non-contact linear actuator with self-locking properties according to claim 5, characterized in that: The height difference between the lower end surface of the first magnetic tile (201) and the lower end surface of the silicon steel sheet (102) is 1 to 1.5 mm.

7. The non-contact linear actuator with self-locking property according to claim 1, characterized in that: It also comprises an output shaft (3), the outer wall of the output shaft (3) and the inner wall of the hollow shaft (101) being threadedly connected.

8. The non-contact linear actuator with self-locking property according to claim 1, characterized in that: It also includes a large ball bearing (4), one end of which is connected to the lower part of the stator housing (203) and the other end of which is matched with the lower part of the hollow shaft (101).

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