High-precision stepping motor

Abstract

The utility model provides a high-precision stepping motor in order to solve the problem that the form and location tolerance, the shaft output height and the axial clearance of the precision of the existing hybrid stepping motor cannot meet the use requirements of various motion mechanisms with higher requirements on stability and motion precision. On the basis of an existing hybrid stepping motor structure, the stator and the front end cover are combined into a whole through the seam allowance and the screw, so that secondary machining can be carried out on the whole of the stator and the front end cover, and the form and location tolerance size of the mounting position of the bearing sleeve is guaranteed; small clearance fit is designed between the bearing sleeve and the first bearing located at the front end and between the bearing sleeve and the second bearing located at the rear end, so that the form and location tolerance precision of the rotor shaft and the motor spigot is improved; the nut is installed at the shaft output end of the motor, and the gasket is installed between the dustproof cover and the second bearing, so that the high-precision shaft output requirement and the axial clearance requirement are met. According to the utility model, the stepping precision can be obviously improved only through small and low-cost improvement without changing the structure of the conventional hybrid stepping motor.

Description

Technical Field

[0001] The utility model relates to a high-precision stepping motor. Background Art

[0002] As an electric actuator, the stepper motor is used to provide power for various mechanisms or component units. It uses electrical pulse signals for control, converts electrical pulses into angular displacement, and achieves precise motion control through the frequency and number of pulse signals. Stepper motor control can also be closed-loop controlled, adding a position sensor at the end of the mechanism to achieve high-precision closed-loop control of the mechanism components.

[0003] Among them, hybrid stepper motors are widely used in medical equipment, automation equipment, aerospace and other fields due to their advantages of large output torque, small step angle and good dynamic performance. However, the geometric tolerance, shaft height and axial clearance of existing hybrid stepper motors cannot meet the needs of various motion mechanisms with high requirements for stability and motion accuracy, such as component mechanisms in the fields of aerospace, medical equipment and automation equipment. Utility Model Content

[0004] In order to solve the technical problem that the shape and position tolerances, shaft height and axial clearance of the existing hybrid stepper motor cannot meet the use requirements of various motion mechanisms with high requirements for stability and motion accuracy, the utility model proposes a high-precision stepper motor.

[0005] The technical solution of the utility model is:

[0006] A high-precision stepper motor comprises a housing, a front end cover, a rotor, a stator, a bearing sleeve, a first bearing, a second bearing and a dust cover; the first bearing is located at the front end cover and is used to support the front end of the rotor shaft; the second bearing is located at the dust cover and is used to support the rear end of the rotor shaft;

[0007] Its special features are:

[0008] The stator and the front end cover are integrated into one body through stoppers and screws;

[0009] The bearing sleeve and the first bearing, as well as the bearing sleeve and the second bearing are all fitted with a small clearance;

[0010] A nut is installed at the motor shaft end, and screwing the nut can push the bearing sleeve and the rotor to move backward to achieve the height adjustment of the motor shaft;

[0011] A gasket is installed between the dust cover and the second bearing.

[0012] Furthermore, the fitting clearance between the bearing sleeve and the first bearing, and between the bearing sleeve and the second bearing is determined according to the shape and position tolerance requirements of the rotor shaft and the motor stop as required by the design.

[0013] Furthermore, a gap between the bearing sleeve and the first bearing is 0-0.009 mm, and a gap between the bearing sleeve and the second bearing is 0-0.011 mm.

[0014] Furthermore, the thickness of the gasket is determined according to the required axial clearance.

[0015] The beneficial effects of the utility model are:

[0016] 1. Based on the existing hybrid stepper motor structure, the utility model combines its stator and front cover into one body through stoppers and screws, supports secondary machining of the two as a whole, ensures the shape and position tolerance size requirements of the motor stopper and the installation position of the bearing sleeve; the gap between the bearing sleeve and the first bearing at the front cover, and between the bearing sleeve and the second bearing on the rotor are designed to be small clearance fit, which improves the shape and position tolerance accuracy of the rotor shaft and the motor stopper; a nut is installed at the motor shaft end, and a gasket is installed between the dust cover at the rear end of the motor and the second bearing, which achieves high-precision shaft output requirements and axial clearance requirements. Finally, the accuracy of the entire stepper motor is improved, so that the stepper motor can meet the use requirements of various motion mechanisms with high requirements for stability and motion accuracy, such as component mechanisms in the fields of aerospace, medical equipment, and automation equipment.

[0017] 2. The utility model does not need to change the structure of the existing hybrid stepper motor, and only needs to make small, low-cost improvements on the basis of the existing hybrid stepper motor to significantly improve the accuracy of the stepper motor. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a cross-sectional view of the utility model. DETAILED DESCRIPTION

[0019] The utility model is further described in detail below in conjunction with the accompanying drawings.

[0020] like Figure 1As shown, the high-precision stepper motor provided by the utility model is a hybrid stepper motor, which is a motor that combines the advantages of permanent magnet and reactive stepper motors. Its working principle is to generate a magnetic field through the current change of the stator winding, which interacts with the magnetic field of the rotor permanent magnet and the reactive iron core, thereby driving the rotor to rotate. The high-precision stepper motor of the utility model includes a housing, a rotor 1, a nut 2, a front cover 3, a stator 4, a bearing sleeve 5, a first bearing 6, a silicone rubber 7, a second bearing 8, a dust cover 9 and a gasket 10. The housing is fixedly connected to the stator 4 and is potted as an integral part by glue; the silicone rubber 7 is used to block the outlet position of the stator lead wire used to connect to the power supply to prevent foreign matter from entering the motor.

[0021] The utility model can improve the precision of the stepper motor by making minor low-cost improvements while keeping the main structure of the existing hybrid stepper motor unchanged. The specific improvements are:

[0022] 1) The stator 4 and the front end cover 3 in the existing stepping motor are combined into an integral part through the stopper and screws, so that the two can be machined as a whole to ensure the shape and position tolerance requirements of the installation position of the motor stopper and the bearing sleeve 5;

[0023] 2) The bearing sleeve 5 and the first bearing 6 at the front end cover 3 (i.e., the bearing for supporting the front end of the rotor shaft), and the bearing sleeve 5 and the second bearing 8 at the dust cover 9 (the bearing for supporting the rear end of the rotor shaft) are both matched with small clearances, so as to meet the high-precision form and position tolerance requirements of the rotor shaft of the rotor 1 and the motor stop; preferably, the clearance between the bearing sleeve 5 and the first bearing 6 at the front end cover 3 is 0-0.009mm, and the clearance between the bearing sleeve 5 and the second bearing 8 at the dust cover 9 is 0-0.011mm.

[0024] 3) Install the nut 2 at the motor shaft end, and install the gasket 10 between the dust cover 9 at the rear end of the motor and the second bearing 8. During the specific assembly, first push the bearing sleeve 5 and the rotor 1 slowly backward by screwing the nut 2, and adjust the motor high-precision shaft height to meet the design requirements. After the adjustment is completed, the contact position of the nut 2 and the front cover 3, and the contact position of the nut 2 and the bearing sleeve 5 are fixed with glue, and finally adjust the thickness of the gasket 10 at the dust cover 9 to achieve the high-precision axial clearance requirements of the motor.

Claims

1. A high-precision stepper motor, comprising a housing, a front end cover, a rotor, a stator, a bearing sleeve, a first bearing, a second bearing and a dust cover; the first bearing is located at the front end cover and is used to support the front end of the rotor shaft; the second bearing is located at the dust cover and is used to support the rear end of the rotor shaft; Features: The stator and the front end cover are integrated into one body through stoppers and screws; The bearing sleeve and the first bearing, as well as the bearing sleeve and the second bearing are all fitted with a small clearance; A nut is installed at the motor shaft end, and screwing the nut can push the bearing sleeve and the rotor to move backward to achieve the height adjustment of the motor shaft; A gasket is installed between the dust cover and the second bearing.

2. The high-precision stepper motor according to claim 1, characterized in that: The fitting clearance between the bearing sleeve and the first bearing, and between the bearing sleeve and the second bearing is determined according to the shape and position tolerance requirements of the rotor shaft and the motor stop as required by the design.

3. The high-precision stepper motor according to claim 2, characterized in that: The gap between the bearing sleeve and the first bearing is 0-0.009 mm, and the gap between the bearing sleeve and the second bearing is 0-0.011 mm.

4. The high-precision stepper motor according to claim 3, characterized in that: The thickness of the gasket is determined according to the required axial clearance.

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