WO2020082909A1

WO2020082909A1 - Linear motor and control method therefor

Info

Publication number: WO2020082909A1
Application number: PCT/CN2019/104635
Authority: WO
Inventors: 谢芳; 郜曦; 焦雷; 刘伟健; 肖智勇; 张智超
Original assignee: 珠海格力电器股份有限公司
Priority date: 2018-10-23
Filing date: 2019-09-06
Publication date: 2020-04-30
Also published as: CN109038995A

Abstract

The present invention provides a linear motor and a control method therefor. The linear motor comprises a base (1), a stator assembly (2), and a mover assembly (3); the stator assembly (2) is slidably disposed on the base (1). The linear motor according to the present invention can shorten the length of the stator while ensuring the moving length of the mover, and therefore, the costs of the linear motor are reduced.

Description

Linear motor and its control method

Related application

This disclosure requires the priority of the Chinese patent application with the application number 201811237230.4 and the name “Linear motor and its control method”, which was filed on October 23, 2018. The entire content of which is hereby incorporated by reference.

Technical field

The present disclosure belongs to the technical field of motors, and particularly relates to a linear motor and its control method.

Background technique

The traditional linear motion adopts the structure of "rotating motor + ball screw". The screw structure is used to convert the motion of the rotating motor to the linear motion required by the application, but there are many problems with this transmission method. With the advancement of related technologies, the linear servo motor (hereinafter referred to as "linear motor") that has re-emerged in recent years has effectively solved the problem of the structure of "rotating motor + ball screw": the linear motor has no screw, so its length The limitation of screw length, the absolute accuracy, repeatability, maximum speed and maximum acceleration of linear motors are higher.

The working principle of a linear motor can be simply understood as pulling a rotating electrical machine into a straight line along the tangential direction of the motor, the stator part becomes the stator, and the moving rotor part becomes the mover. On the one hand, the linear motor products currently on the market fix the stator at a fixed position such as the stator base and arrange the entire length along the moving direction of the mover. The slide rail is also fixed, and only the mover moves along the straight line on the slide rail. On the other hand, due to motor material cost and production process considerations, the current linear motor products on the market mostly use windings as movers and permanent magnets as stators, short mover primary and long stator secondary structures. To sum up the two points, the length of the stator in the moving direction is equal to the moving length of the mover, and the price of rare earth permanent magnets is as high as 350 yuan / kg. Some high-grade permanent magnets are even higher in price, while the materials such as winding copper wire and steel are only It is 1/8 of the price, so the cost of the stator material composed of permanent magnets is extremely high.

Summary of the invention

Therefore, the technical problem to be solved by the present disclosure is to provide a linear motor and a control method thereof, which can shorten the length of the stator while ensuring the moving length of the mover and reduce the cost of the linear motor.

In order to solve the above problems, the present disclosure provides a linear motor including a base, a stator assembly and a mover assembly, the stator assembly being slidably disposed on the base.

In one of the embodiments, the mover assembly is disposed corresponding to the stator assembly, and is slidably disposed on the base.

In one of the embodiments, a stator guide rail is provided on the base, and the stator assembly is slidably provided on the stator guide rail.

In one of the embodiments, the stator assembly includes a stator magnetic steel and a stator core disposed on two opposite sides of the stator magnetic steel, and the stator core can be slidably disposed on the stator guide rail.

In one of the embodiments, a mover slide rail is provided on the base, and the mover assembly is slidably disposed on the mover slide rail.

In one of the embodiments, a thrust device is further provided on the base. The thrust device is used to provide a thrust effect to the stator assembly, so that the stator assembly and the mover assembly move in the same direction.

In one of the embodiments, the thrust device further includes a trigger unit. The trigger unit is disposed on the motion path of the stator assembly, and controls the thrust device to work after the stator assembly triggers the trigger unit.

In one of the embodiments, a trigger unit is provided at both ends of the base along the sliding direction of the stator assembly.

In one of the embodiments, the thrust device includes a spring, a hydraulic device, a pneumatic device, a screw drive device, or an electric propulsion device.

In one of the embodiments, there are two mover slide rails. The two mover slide rails are arranged in parallel and at the same height. The mover assembly is supported by the mover slide rails and suspended on the stator assembly.

According to another aspect of the present disclosure, there is provided a control method of the above linear motor, including:

S1: Power on the linear motor;

S2: energize the mover assembly, move the mover assembly to a preset position, and control the mover assembly and the stator assembly to move in opposite directions;

S3: Detect the movement position of the stator assembly, when the stator assembly moves to the preset position, apply a reverse thrust to the stator assembly to make the stator assembly and the mover assembly move in the same direction;

S4: After the mover assembly moves to the preset position, the reverse movement of the mover assembly is energized to control the mover assembly and the stator assembly to move in opposite directions;

S5: Repeat steps S3 and S4.

In one of the embodiments, step S3 includes:

Detect the trigger signal of the stator assembly;

After receiving the trigger signal of the stator assembly, the thrust device is controlled to push the stator assembly in reverse.

The linear motor provided by the present disclosure includes a base, a stator assembly, and a mover assembly. The stator assembly can be slidably disposed on the base. Since the stator assembly itself can also move relative to the base, the movable feature of the stator assembly can be used to achieve the purpose of achieving a longer movement distance with a shorter stroke, which can greatly shorten the length of the stator assembly and increase the length of the stator assembly. The utilization rate reduces the amount of permanent magnets on the stator assembly and reduces the cost of linear motor moving coil materials.

BRIEF DESCRIPTION

1 is a schematic diagram of a three-dimensional structure of a linear motor according to an embodiment of the present disclosure;

2 is a schematic structural diagram of a linear motor according to an embodiment of the present disclosure;

FIG. 3 is a schematic sectional view taken along the line A-A of FIG. 2;

4 is a flowchart of a control method of a linear motor according to an embodiment of the present disclosure.

The reference signs are expressed as:

1. Base; 2. Stator assembly; 3. Mover assembly; 4. Stator guide rail; 5. Stator magnet; 6. Stator core; 7. Mover slide rail; 8. Thrust device

detailed description

Referring to FIG. 1 to FIG. 3 in combination, according to an embodiment of the present disclosure, a linear motor includes a base 1, a stator assembly 2 and a mover assembly 3, and the stator assembly 2 is slidably disposed on the base 1. In one of the embodiments, the mover assembly 3 is disposed corresponding to the stator assembly 2 and is slidably disposed on the base 1.

Since the stator assembly 2 itself can also move relative to the base 1, the characteristics of the stator assembly 2 can be used to achieve the purpose of achieving a longer movement distance with a shorter stroke, which can ensure that the movement length of the mover assembly 3 remains unchanged The length of the stator assembly is greatly shortened, the utilization rate of the stator assembly in the longitudinal direction is increased, the amount of permanent magnets on the stator assembly is reduced, and the material cost of the linear motor is reduced.

A stator guide rail 4 is provided on the base 1, and the stator assembly 2 is slidably provided on the stator guide rail 4. The stator guide rail 4 is provided at the bottom of the stator assembly 2 and can form a bottom support for the stator assembly 2 so that the stator assembly 2 is suspended relative to the base 1 to reduce the contact area between the stator assembly 2 and the base 1 and reduce the stator assembly 2 Sliding friction.

In this embodiment, the stator assembly 2 includes a stator magnet 5 and stator cores 6 provided on two opposite sides of the stator magnet 5. The stator core 6 is slidably provided on the stator guide rail 4. The stator core 6 has a T-shaped structure, and the stator guide rails 4 are two. The two sides of the T-shaped structure are respectively supported. A groove is provided in the middle of the T-shaped structure for placing the stator magnetic steel 5, wherein the stator magnetic steel 5 is consistent with the height of the top of the stator core 6. The stator core 6 is designed to be T-shaped, which can reduce the material consumption of the stator assembly 2 and reasonably use the structure of the stator core 6 to set the stator magnet 5 to reduce the overall volume of the stator assembly 2 and can effectively ensure the stator core 6 Structural strength.

A mover slide rail 7 is provided on the base 1, and the mover assembly 3 is slidably provided on the mover slide rail 7. In this embodiment, both ends of the mover slide rail 7 are fixed on the base 1, and the mover slide rail 7 is threaded on the mover assembly 3, while guiding the mover assembly 3, The mover assembly 3 plays a supporting role, so that the mover assembly 3 is suspended on the stator assembly 2 to avoid contact between the mover assembly 3 and the stator assembly 2 and can effectively ensure the contact between the mover assembly 3 and the stator assembly 2 The air gap ensures the movement performance of the mover assembly 3. The height of the mover slide rail 7 can be adjusted, so that the air gap between the mover assembly 3 and the stator assembly 2 can be adjusted reasonably, and the magnetic performance of the mover assembly 3 and the stator assembly 2 can be improved. There are two mover slide rails 7, and the two mover slide rails 7 are arranged in parallel and at the same height. The movable runner 7 may be a round rod, a square rod, or other rod-shaped structures.

A thrust device 8 is also provided on the base 1. The thrust device 8 is used to provide a thrust effect to the stator assembly 2, so that the stator assembly 2 and the mover assembly 3 move in the same direction. The thrust device 8 includes a spring, a hydraulic device, a pneumatic device, a screw drive device or an electric propulsion device, and may also provide other mechanisms that can provide a thrust effect to the stator assembly 2 so that the stator assembly 2 moves along the moving direction of the mover assembly 3或装置。 Or devices.

The thrust device 8 further includes a trigger unit, which is disposed on the movement path of the stator assembly 2 and controls the thrust device 8 to work after the stator assembly 2 triggers the trigger unit. The trigger unit is a travel switch or a micro switch. The trigger unit is connected to the control unit of the thrust device 8 and can send a trigger signal to the control unit, so that the control unit sends out corresponding control signals to control the thrust device 8 to move the stator assembly 2 relative to the base 1.

Both ends of the base 1 along the sliding direction of the stator assembly 2 are provided with a trigger unit, and a thrust device 8 can provide a thrust function for the stator assembly 2 to ensure the stator when the stator assembly 2 moves to a preset position at both ends of the base 1 The assembly 2 can move along the base 1 a sufficient distance, and the movement of the stator assembly 2 shortens the amount of permanent magnets on the stator assembly 2 and reduces the cost of the stator assembly 2.

After the linear motor is energized, the stator assembly 2 and the mover assembly 3 generate thrust due to the interaction of electromagnetic induction. The mover assembly 3 moves horizontally along the mover slide 7 in the specified direction, and the stator assembly 2 is affected by the mover assembly 3 The force in the opposite direction moves in the opposite direction to the mover assembly 3. When the stator assembly 2 moves to the preset position, it will squeeze and touch the thrust device 8, the thrust device 8 triggers and pushes the stator assembly 2 in the reverse direction, so that The movement direction of the stator assembly 2 is consistent with the movement direction of the mover assembly 3. When the mover assembly 3 moves to the limit position, the motor driver inputs the motor coil winding signal to generate a reverse traveling wave magnetic field, and the mover assembly 3 is subjected to the reverse magnetic field The reverse horizontal movement starts, and at this time, the stator assembly 2 maintains the reverse horizontal movement of the stator assembly 2 and the mover assembly 3 through the thrust device 8 at the other end, and finally achieves the effect of the horizontal reciprocating movement of the linear motor.

Referring to FIG. 4 in combination, according to an embodiment of the present disclosure, a control method of the above linear motor includes: S1: power on the linear motor; S2: power on the mover subassembly 3, so that the mover subassembly 3 is preset Position movement, control the mover assembly 3 and the stator assembly 2 to move in opposite directions; S3: detect the movement position of the stator assembly 2, when the stator assembly 2 moves to the preset position, apply a reverse thrust to the stator assembly 2 to make the stator assembly 2 Move in the same direction as mover assembly 3; S4: When mover assembly 3 moves to a preset position, energize mover assembly 3 in reverse to control mover assembly 3 and stator assembly 2 to move in opposite directions; S5: Repeat Steps S3 and S4.

After the motor starts to be energized, an interaction force is generated between the mover assembly 3 and the stator assembly 2 due to electromagnetic induction, and the two move along the mover slide rail 7 and the stator guide rail 4 in opposite directions, respectively. The stator assembly 2 will move to one end of the linear base 1 of the motor, and the stator assembly 2 triggers the thrust device 8 installed inside the marble base 1 at one end of the motor by extrusion or the like. The thrust device 8 is triggered to generate a thrust opposite to the original movement direction of the stator assembly 2. The stator assembly 2 that is pushed in the reverse direction by the thrust device 8 changes the direction of movement and moves in the opposite direction, which is consistent with the movement direction of the mover assembly 3. Then through the interaction force between the mover assembly 3 and the stator assembly 2, the stator assembly 2 "transmits" the thrust force of the thrust device 8 to the mover assembly 3, so that the mover assembly 3 can finally move to the target position, which is completed Once the triggering process of the thrust device 8 is performed, it can be reciprocated in accordance with the above control process thereafter.

Step S3 includes: detecting the trigger signal of the stator assembly 2; after receiving the trigger signal of the stator assembly 2, controlling the thrust device 8 to push the stator assembly 2 in reverse.

It is easily understood by those skilled in the art that the above-mentioned advantageous methods can be freely combined and superimposed on the premise of no conflict.

The above are only the preferred embodiments of the present disclosure and are not intended to limit the present disclosure. Any modification, equivalent replacement and improvement made within the spirit and principle of the present disclosure shall be included in the scope of protection of the present disclosure Inside. The above are only the preferred embodiments of the present disclosure. It should be noted that those of ordinary skill in the art can make several improvements and modifications without departing from the technical principles of the present disclosure. These improvements and modifications should also It is regarded as the scope of protection of this disclosure.

Claims

A linear motor includes a base (1), a stator assembly (2) and a mover assembly (3), the stator assembly (2) is slidably disposed on the base (1).
The linear motor according to claim 1, characterized in that the mover assembly (3) is provided corresponding to the stator assembly (2), and is slidably provided on the base (1).
The linear motor according to claim 1, characterized in that a stator guide rail (4) is provided on the base (1), and the stator assembly (2) is slidably provided on the stator guide rail (4) .
The linear motor according to claim 3, wherein the stator assembly (2) includes a stator magnetic steel (5) and a stator core (6) disposed on two opposite sides of the stator magnetic steel (5) ), The stator core (6) is slidably arranged on the stator guide rail (4).
The linear motor according to claim 2, characterized in that a mover slide rail (7) is provided on the base (1), and the mover assembly (3) is slidably disposed on the mover slide On the rail (7).
The linear motor according to any one of claims 1 to 5, wherein a thrust device (8) is further provided on the base (1), and the thrust device (8) is used for the stator The assembly (2) provides a thrust effect to move the stator assembly (2) and the mover assembly (3) in the same direction.
The linear motor according to claim 6, characterized in that the thrust device (8) further comprises a trigger unit, the trigger unit being disposed on the movement path of the stator assembly (2), and in the stator assembly (2) After the trigger unit is triggered, the thrust device (8) is controlled to work.
The linear motor according to claim 7, characterized in that both ends of the base (1) along the sliding direction of the stator assembly (2) are provided with the trigger unit.
The linear motor according to claim 6, characterized in that the thrust device (8) comprises a spring, a hydraulic device, a pneumatic device, a screw drive device or an electric propulsion device.
The linear motor according to claim 5, characterized in that there are two movable runners (7), and the two movable runners (7) are arranged in parallel and located at the same height, and the movable The sub-assembly (3) is supported by the mover slide rail (7) and suspended on the stator assembly (2).
A control method applied to a linear motor according to any one of claims 1 to 10, including:

S1: Power on the linear motor;

S2: energize the mover assembly (3), move the mover assembly (3) to a preset position, and control the mover assembly (3) and the stator assembly (2) to move in opposite directions;

S3: Detect the moving position of the stator assembly (2), when the stator assembly (2) moves to the preset position, apply a reverse thrust to the stator assembly (2), so that the stator assembly (2) and the mover assembly (3) are the same Movement

S4: After the mover assembly (3) moves to a preset position, energize the mover assembly (3) in reverse to control the mover assembly (3) and the stator assembly (2) to move in opposite directions;

S5: Repeat steps S3 and S4.
The control method according to claim 10, wherein the step S3 comprises:

Detect the trigger signal of the stator assembly (2);

After receiving the trigger signal of the stator assembly (2), the thrust device (8) is controlled to push the stator assembly (2) in reverse.