Torque detection structure of electric actuator

Abstract

The utility model discloses a torque detection structure for an electric actuator, and the electric actuator comprises a motor, a housing, and a worm and gear transmission structure disposed in the housing. The torque detection structure comprises a rolling bearing fixedly connected to one end of the worm, a bearing sleeve arranged on the rolling bearing in a sleeving mode, a sliding block arranged on the outer wall of the bearing sleeve, a sliding groove formed in the shell in the axial direction of the worm and a linear displacement sensor arranged in the shell, and when the worm moves in the axial direction, the sliding block moves in the sliding groove, and the linear displacement sensor detects the torque of the worm. The linear displacement sensor detects the displacement amount of the sliding block and sends a signal to the controller. The displacement of the sliding block is detected through the linear displacement sensor, a signal is sent to the controller, the maximum torque of the electric actuator can be quantitatively adjusted, the torque of the electric actuator is prevented from being overloaded, and the electric actuator is reliable, durable, simple in structure, convenient to machine and easy to assemble.

Description

Technical Field

[0001] The utility model relates to the technical field of electric actuators, in particular to a torque detection structure of an electric actuator. Background Art

[0002] When an electric actuator is in use, if torque overload occurs, it may damage the valve and the electric actuator. Therefore, a torque protection structure needs to be set. When the actuator operates, the worm will produce axial displacement under the action of the worm gear. The common mechanical structure adopts a fork form. The fork is placed in the worm groove, and the axial displacement of the worm drives the fork to deflect. Its disadvantage is that the part of the fork placed in the groove always contacts the worm groove at the same position when swinging, which is very easy to wear. After a long operation time, it is easy to cause the torque protection to fail. Moreover, when the worm is at different displacement sizes, the rotation angle of the fork is non-linear, so linear adjustment of the torque cannot be achieved, and only the point signal value of the set torque can be output. In addition, pressure sensors can be set at both ends of the worm, and the torque can be calculated through the data of the pressure sensors. However, the cost of the pressure sensors is relatively high, and if the displacement of the worm exceeds the limit of the pressure sensors, the pressure sensors will be damaged. Summary of the Utility Model

[0003] Aiming at the existing technical deficiencies, the utility model provides a torque detection structure of an electric actuator.

[0004] In order to achieve the above purpose, the technical solution adopted by the utility model is: a torque detection mechanism of an electric actuator, including a motor, a housing, and a worm and worm gear transmission mechanism arranged in the housing. The torque detection structure is characterized in that it includes a rolling bearing fixedly connected to one end of the worm, a bearing sleeve sleeved on the rolling bearing, a slider arranged on the outer wall of the bearing sleeve, a chute arranged on the housing along the axial direction of the worm, and a linear displacement sensor arranged in the housing. The slide bar of the linear displacement sensor is clamped in the card slot on the slider on the outer wall of the bearing sleeve. When the worm has an axial displacement, the slider moves in the chute, thereby driving the linear displacement sensor to detect the displacement of the slider and send a signal to the controller.

[0005] Preferably, the linear displacement sensor includes a bracket, and the bracket is fixedly connected to the housing.

[0006] The beneficial effects of the utility model: By detecting the displacement of the slider by the linear displacement sensor and sending a signal to the controller, the utility model can achieve quantitative adjustment of the maximum torque of the electric actuator to protect the torque of the electric actuator from being overloaded. The utility model is reliable, durable, simple in structure, convenient to process and easy to assemble. Description of the Drawings

[0007] Figure 1 It is a sectional view of the utility model;

[0008] Figure 2 is Figure 1 a partially enlarged view of;

[0009] Figure 3 is a structural schematic diagram of the present utility model. Specific embodiments

[0010] As Figures 1 - 3 shown, a torque detection structure for an electric actuator, the electric actuator includes a motor 1, a housing 2, and a worm and worm gear transmission structure provided in the housing 2. The worm 3 is provided on a worm shaft 4, and bearings 5 are installed on both sides of the worm shaft 4. The worm shaft 4 is installed in the housing 2 through the bearings 5. An elastic support member 6 is provided between the worm 3 and the bearing 5. The elastic support member 6 can be a spring or a disc spring. The motor 1 can directly drive the worm 3 to rotate or drive the worm 3 to rotate through a first-stage reduction transmission structure (such as a gear transmission or a worm and worm gear transmission). The worm 3 then drives the worm gear to rotate and output torque. The torque detection structure includes a rolling bearing 7 fixedly connected to one end of the worm 3, a bearing sleeve 8 sleeved on the rolling bearing 7, a slider 9 provided on the outer wall of the bearing sleeve 8, a chute 10 provided on the housing 2 along the axial direction of the worm, and a linear displacement sensor 11 provided in the housing 2. During operation, the motor 1 drives the worm 3 to rotate, and the worm 3 drives the worm gear to rotate. When the worm gear is subjected to a certain load, in addition to rotating, the worm 3 also generates an axial displacement. When the worm 3 undergoes an axial displacement, the worm 3 drives the rolling bearing 7 and the bearing sleeve 8 to displace together. The outer diameter of the bearing sleeve 8 is smaller than the inner diameter of the housing 2, that is, the outer diameter of the bearing sleeve 8 does not contact the housing 2. The slider 9 on the bearing sleeve 8 moves in the chute 10, and the linear displacement sensor 11 detects the displacement amount of the slider 9 and sends a signal to the controller.

[0011] The linear displacement sensor 11 includes a bracket 12, and the bracket 12 is fixedly connected to the housing 2.

[0012] The linear displacement sensor is a linear slide potentiometer. The slider 9 is provided with a jack 13, and the dial rod 14 of the linear slide potentiometer is inserted into the jack 13.

[0013] During installation and debugging, it is necessary to calibrate the torque of the actuator on a force measuring fixture. Record the signal value output by the linear displacement sensor 11 corresponding to when the torque is zero, and then measure the signal values output by the linear displacement sensor 11 corresponding to the maximum overload torque and several intermediate torque points. Store the above parameters in the controller, process the torque and the signal values to obtain a torque-signal value curve. In this way, an upper limit torque can be set. The controller monitors the signal value. When an overload signal appears, the controller stops the motor 1 from operating to achieve the protection of the actuator.

[0014] The basic principle, main features and advantages of the present utility model have been shown and described above. Those skilled in the art should understand that the present utility model is not limited by the above embodiments. What is described in the above embodiments and the specification only illustrates the principle of the present utility model. Without departing from the spirit and scope of the present utility model, simple modifications and substitutions made by ordinary technical personnel in the field are within the protection scope of the present utility model.

Claims

1. An electric actuator torque detection structure, comprising a motor, a housing, and a worm and worm gear transmission mechanism arranged in the housing, characterized in that, The torque detection structure includes a rolling bearing fixedly connected to one end of the worm, a bearing sleeve sleeved on the rolling bearing, a slider arranged on the outer wall of the bearing sleeve, a chute arranged on the housing along the axial direction of the worm, and a linear displacement sensor arranged in the housing. The slide rod of the linear displacement sensor is clamped in a card slot on the slider on the outer wall of the bearing sleeve. When the worm undergoes axial displacement, the slider moves in the chute, thereby driving the linear displacement sensor to detect the displacement amount of the slider and send a signal to the controller.

2. The torque detection structure of an electric actuator according to claim 1, wherein The linear displacement sensor includes a bracket, and the bracket is fixedly connected to the housing.

Images