Parallel harmonic deceleration electric linear actuator

Abstract

The utility model relates to several parallel harmonic deceleration electric linear actuators. The linear actuator is composed of a parallel harmonic reducer with a built-in motor and a lead screw nut transmission mechanism. A harmonic reducer of the built-in motor has two forms of a built-in outer rotor motor and a built-in inner rotor motor, high-speed rotating motion of the built-in motor is output to a rotating shaft or a shell after being subjected to large-proportion speed reduction and torque increase through the parallel harmonic assembly, and a lead screw or a nut of the lead screw and nut transmission mechanism is driven to do rotary motion. Therefore, the rotary motion is converted into linear motion. Due to the fact that the parallel harmonic assembly is used for speed reduction, the electric linear actuator has the advantages of being large in speed reduction ratio, small in energy consumption loss, high in load capacity, rigidity and precision and the like.

Description

Technical Field

[0001] The utility model relates to the field of electromechanics, in particular to an electric linear actuator with parallel harmonic deceleration. Background Art

[0002] Electric linear actuators use motors as power sources, increase torque through reduction devices, and use screw transmission mechanisms to convert the motor's rotary motion into linear motion. In ordinary electric linear actuators, the motor is installed on one side, directly driving or driving the screw shaft through a planetary reducer to make a low-speed rotary motion, and then pushing the screw nut to perform linear execution motion. This requires a sufficiently large axial installation size, and the planetary reducer has a large tooth gap, low precision, small reduction ratio, and limited load capacity. Planetary roller screws have high precision and high rigidity due to their small pitch, but they have a small reduction ratio, high cost, and high processing precision requirements. Summary of the invention

[0003] In view of the existing technical defects, the utility model, inspired by the ideas of invention patents CN117847173A and 202410418121.1, proposes an electric linear actuator with parallel harmonic reduction. The core principle is to use the parallel harmonic reducer with built-in motor to drive the screw transmission mechanism to achieve the characteristics of high transmission accuracy, low energy consumption, high load capacity and high rigidity.

[0004] To achieve the above purpose, the linear actuator is composed of a parallel harmonic reducer with a built-in motor and a screw-nut transmission mechanism. The parallel harmonic reducer with a built-in motor is composed of a built-in motor, a parallel harmonic component, a housing and a rotating shaft, and has two forms: a built-in external rotor motor and a built-in internal rotor motor. The screw-nut transmission mechanism is mainly composed of a screw, a nut and a rolling element, and can be directly screwed together by the screw and the nut, or can be transmitted by using balls or planetary rollers between the screw and the nut.

[0005] When the parallel harmonic reducer is a built-in external rotor motor type, the inner hole of the stator hollow shaft of the parallel harmonic reducer is provided with a key or spline groove, and the bottom of the screw rod is guided by the key or spline in cooperation with the stator hollow shaft. The nut is mechanically connected to the output housing of the reducer. The high-speed and low-torque of the motor outer rotor is output by the rotating housing after being greatly reduced and increased by the parallel harmonic component. The housing then drives the nut to rotate at a low speed, thereby driving the screw rod to move linearly.

[0006] When the parallel harmonic reducer is a built-in inner rotor motor type, the shaft and the nut are integrated, that is, the inner hole of the shaft is provided with the thread required for the screw drive. One end of the screw has a thread, which is screwed with the nut and placed inside the shaft, and the other end is provided with a guide structure. The outer end of the split guide plate is fixedly connected to the shell, and the inner end is dynamically connected to the guide structure of the screw. The high-speed rotation of the motor rotor is output to the shaft after the parallel harmonic component has a large-scale reduction and increased torque. The shaft drives the nut to rotate at a low speed and drives the screw to move linearly.

[0007] When the parallel harmonic reducer is a built-in inner rotor motor type, the screw and the shaft can also be designed as one, that is, the thread required for the screw transmission is processed on the outer circle of one end of the shaft. The guide cylinder is fixedly connected to the housing, and the linear brake is fixedly connected to the nut and placed in the guide cylinder for guidance. The high-speed rotation of the motor rotor is output to the shaft after the parallel harmonic component has a large-scale reduction and increased torque. The shaft drives the screw to rotate at a low speed, driving the nut to move linearly, and the nut then drives the brake to move linearly.

[0008] The linear actuator uses a dual harmonic component for deceleration, and has the characteristics of low energy loss, high reduction ratio, high load capacity, good rigidity, high execution accuracy, etc. In addition, the thread lead angle of the screw nut transmission mechanism can be designed to match the occasions where the linear actuator has self-locking requirements. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 It is a schematic diagram of an electric linear actuator with a built-in outer rotor motor and parallel harmonic reduction;

[0010] Figure 2 It is a schematic diagram of an electric linear actuator with a built-in inner rotor motor and parallel harmonic reduction;

[0011] Figure 3 It is a schematic diagram of another electric linear actuator with a built-in inner rotor motor and parallel harmonic reduction. DETAILED DESCRIPTION

[0012] In order to make the technical problems, technical solutions and beneficial effects to be solved by the utility model more clearly understood, the utility model is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described here are only used to explain the utility model and are not used to limit the utility model.

[0013] In the following description, specific details such as specific internal procedures and techniques are provided for the purpose of illustration rather than limitation, so as to provide a thorough understanding of the embodiments of the present invention. However, it should be clear to those skilled in the art that the present invention may be implemented in other embodiments without these specific details. In other cases, detailed descriptions of well-known systems, devices, circuits, and methods are omitted to avoid obstructing the description of the present invention with unnecessary details.

[0014] Embodiment 1

[0015] like Figure 1 As shown, the utility model provides a schematic diagram of an electric linear actuator with a built-in outer rotor motor parallel harmonic reduction, which includes a built-in motor parallel harmonic reducer 1 and a screw nut transmission mechanism 2. The built-in motor parallel harmonic reducer mainly includes a stator 101, an outer rotor 102, a harmonic component 103, a housing 104, and a stator hollow shaft 105. The screw nut transmission mechanism is mainly composed of a screw 201 and a nut 202.

[0016] The inner hole of the stator hollow shaft 101 is provided with a key or spline groove, and the bottom of the screw rod 201 cooperates with the stator hollow shaft 105 through the key or spline 201A for guidance. The nut 202 is mechanically connected to the output housing 104 on one side of the parallel harmonic reducer 1. The high-speed rotation motion of the motor outer rotor 102 is output to the output housing 104 through the parallel harmonic component 104, and the output housing 104 drives the nut 202 to perform low-speed rotation motion, and drives the screw rod 201 to perform linear motion, so as to realize linear output.

[0017] Embodiment 2

[0018] like Figure 2 As shown, the utility model provides a schematic diagram of an electric linear actuator with a built-in inner rotor motor and parallel harmonic reduction. The difference from the first embodiment is that the built-in motor is connected in parallel with the harmonic reducer output, and the built-in motor is an inner rotor type, mainly including a stator 101, an inner rotor 106, a harmonic component 103, a housing 104, and a rotating shaft 107.

[0019] The rotating shaft 107 is in the form of a hollow shaft and is integrated with the nut 202, that is, the inner hole of the rotating shaft 107 is provided with a thread required for the screw drive 2. One end of the screw 201 is threaded and screwed with the nut 202 and placed inside the rotating shaft 201. The other end is provided with a guide structure. The outer end of the split guide plate 204 is fixedly connected to the housing, and the inner end is dynamically connected to the guide structure of the screw 201. The high-speed rotation of the inner rotor 106 is output to the rotating shaft 107 through the parallel harmonic component 103. The rotating shaft 107 rotates at a low speed, and the screw 201 is driven to perform linear motion by the screwing of the thread.

[0020] Embodiment 3

[0021] like Figure 3 As shown, the utility model provides another schematic diagram of an electric linear actuator with a built-in inner rotor motor and parallel harmonic reduction. The difference from the second embodiment is that the screw rod 201 and the rotating shaft 107 are designed as one body, that is, the screw rod 201 is regarded as an extension at one end of the rotating shaft 107. The nut 202 is in the form of a short nut and is integrated with the actuator 205. The actuator is built into the guide cylinder 206 and supported by the support ring 207. The support ring is provided with a sealing device 208. The high-speed rotational motion of the inner rotor 106 is output to the rotating shaft 107 through the parallel harmonic component 103. The rotating shaft 107 drives the screw rod 201 to rotate at a low speed, drives the nut 202 to perform linear motion, and the nut 202 further drives the actuator 205 to perform linear motion.

[0022] In the first, second and third embodiments, the screw rod 201 and the nut 202 can be directly screwed together through the thread, or can be transmitted by using rolling bodies such as balls, rollers, planetary rollers, etc. between the screw rod and the nut. Compared with the electric linear actuator combined with the conventional motor and screw rod transmission mechanism, the parallel harmonic reducer with built-in motor is used to provide power and reduce speed, and has the characteristics of large reduction ratio, high precision, high load capacity, high rigidity, etc. Since the screw rod 201 is built into the stator shaft 105 or the rotating shaft 107 in the parallel harmonic reducer in the first and second embodiments, it also has the characteristic of small axial size.

[0023] The preferred specific embodiments of the utility model are described in detail above. It should be understood that a person skilled in the art can make many modifications and changes according to the concept of the utility model without creative work. Therefore, any technical solution that can be obtained by a person skilled in the art through logical analysis, reasoning or limited experiments based on the concept of the utility model on the basis of the prior art should be within the scope of protection determined by the claims.

Claims

1. The electric linear actuator with parallel harmonic reduction is characterized by: The linear actuator is composed of a parallel harmonic reducer with a built-in motor and a screw-nut transmission mechanism; the parallel harmonic reducer with a built-in motor is composed of a built-in motor, a parallel harmonic component, a housing and a rotating shaft, and has two forms: a built-in external rotor motor and a built-in internal rotor motor; the screw-nut transmission mechanism is mainly composed of a screw and a nut, which can be a direct screw-in transmission of the screw and the nut, or a transmission using balls, rollers or planetary rollers between the screw and the nut.

2. The parallel harmonic reduction electric linear actuator according to claim 1, characterized in that: When the parallel harmonic reducer is of the built-in outer rotor motor type, the inner hole of the stator hollow shaft of the parallel harmonic reducer is provided with a key or spline groove, and the bottom of the screw rod is guided by the key or spline in cooperation with the stator hollow shaft; the nut is mechanically connected to the output housing of the reducer; the high-speed and low-torque of the motor outer rotor is output by the rotating housing after being greatly reduced and increased in torque by the parallel harmonic component, and the housing then drives the nut to rotate at a low speed, thereby driving the screw rod to make a linear motion.

3. The parallel harmonic reduction electric linear actuator according to claim 1, characterized in that: When the parallel harmonic reducer is of the built-in inner rotor motor type, the shaft and the nut are integrated into one, that is, the inner hole of the shaft is provided with a thread required for the screw transmission; one end of the screw has a thread, which is screwed with the nut and placed inside the shaft, and the other end is provided with a guide structure; the outer end of the split guide plate is fixedly connected to the outer shell, and the inner end is dynamically connected to the guide structure of the screw; the high-speed rotation motion of the motor rotor is output to the shaft after being greatly reduced in proportion and the torque is increased by the parallel harmonic component, and the shaft drives the nut to rotate at a low speed and drives the screw to make a linear motion.

4. The electric linear actuator with parallel harmonic reduction according to claim 1 or 3, characterized in that: When the parallel harmonic reducer is of the built-in inner rotor motor type, the lead screw and the rotating shaft can also be designed as one body, that is, the thread required for the lead screw transmission is processed on the outer circle of one end of the rotating shaft; the guide cylinder is fixedly connected to the outer shell, and the linear brake and the nut are integrated into one body and placed in the guide cylinder for guiding; the high-speed rotation motion of the motor rotor is output to the rotating shaft after being greatly reduced in proportion and the torque is increased by the parallel harmonic component, and the rotating shaft drives the lead screw to rotate at a low speed, driving the nut to make a linear motion, and the nut then drives the brake to move linearly.

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