CN212305001U

CN212305001U - Compact electromechanical actuator

Info

Publication number: CN212305001U
Application number: CN202020455072.6U
Authority: CN
Inventors: 王贺龙; 姜玉峰; 李俊岩; 陈鹏; 高健; 侯鹏飞; 张雨; 徐豪榜
Original assignee: China Academy of Launch Vehicle Technology CALT; Beijing Research Institute of Precise Mechatronic Controls
Current assignee: China Academy of Launch Vehicle Technology CALT; Beijing Research Institute of Precise Mechatronic Controls
Priority date: 2020-04-01
Filing date: 2020-04-01
Publication date: 2021-01-05
Anticipated expiration: 2030-04-01

Abstract

A compact electromechanical actuator comprises a bolt assembly 1, an actuator shell 2, a limiting flange assembly 3, a ball screw 4, a rotor nut 5, a servo motor stator assembly 8, a bidirectional thrust bearing 9 and a deep groove ball bearing 10; the right end of the ball screw 4 is matched with the rotor nut 5 for use, both sides of the rotor nut 5 are of a stepped shaft structure, the bidirectional thrust bearing 9 is sleeved from the left side, and then the two sides are respectively sleeved into the deep groove ball bearings 10; the deep groove ball bearing 10 and the bidirectional thrust bearing 9 are fixed in the servo motor assembly 8 and are axially fixed; the rotor nut 5 is used as a rotor of a servo motor, the motor is started, the inner side of the bidirectional thrust bearing 9 rotates, and the rotor nut 5 rotates under the support of the deep groove ball bearing 10 to drive the ball screw 4 to do linear reciprocating motion.

Description

Compact electromechanical actuator

Technical Field

The invention belongs to the field of electromechanical servo, and particularly relates to a compact electromechanical actuator.

Background

The electromechanical actuator is an important executing mechanism of a control system, and in the field of aerospace, the electromechanical actuator is generally used for pushing an air rudder load to swing so as to realize control of aerodynamic force load of a control surface and realize posture adjustment of weapons or carrying and the like.

In recent years, with the technical development of novel hypersonic weapons, novel miniaturized exquisite weapons are applied more and more, and the novel hypersonic weapons are mainly characterized in that the products are lighter, the maneuverability is stronger, the flight time is longer, and the flight distance is longer.

The higher the corresponding requirements on the servo actuator are, the more the following are mainly reflected: the installation space requirement is more compact, the zero position installation is short, the stroke requirement is large, the power-to-mass ratio requirement is high, and the dynamic characteristic requirement is high. The traditional electromechanical actuator of the servo system mostly adopts a transmission mode of a permanent magnet synchronous motor and a ball screw. The ball screw realizes that the rotary motion of the motor is converted into linear motion to be output, and in order to prevent rotation, the screw can be provided with an anti-rolling device which is realized through a guide post or a guide sliding block. Meanwhile, the actuator shell needs to be provided with a matched guide groove structure, and the guide groove machining precision requirement is high in order to meet the high-precision transmission requirement.

The output shaft of the motor is connected with the ball screw (or the ball nut) through a single key or a double key, the machining precision requirement on a hub groove and a key groove is high generally in order to guarantee the high dynamic and quick response requirements of the electromechanical actuator, the key is usually repaired or selected during assembly, and the assembly efficiency is low.

In addition, in the field of aerospace, the electromechanical actuator can often carry out dynamic characteristic test, and in the process of large-torque and dynamic loading, parts such as guide columns, guide bearings, keys or grooves are frequently subjected to alternating load, so that failure is frequent.

Therefore, the product function ratio is improved, the integration degree of the electromechanical actuator is improved, and the trend of future technical development is provided for the aircraft layout with stronger adaptability and more compact space.

Disclosure of Invention

A compact electromechanical actuator comprises a ball screw, a rotor nut, a bidirectional thrust bearing, a deep groove ball bearing and a servo motor stator assembly; the right end of the ball screw is matched with a rotor nut, both sides of the rotor nut are of stepped shaft structures, a bidirectional thrust bearing is sleeved from the left side, and then the two sides of the bidirectional thrust bearing are sleeved into the deep groove ball bearings respectively; the deep groove ball bearing and the bidirectional thrust bearing are fixed in the servo motor assembly and are axially fixed; the rotor nut is used as an electric rotor of the servo motor, the motor is started, the inner side of the bidirectional thrust bearing rotates, and the rotor nut rotates to drive the ball screw to do linear reciprocating motion under the support of the deep groove ball bearing.

Furthermore, threads are arranged on the outer side of the stepped shaft structure on the left side of the rotor nut, and the bidirectional thrust bearing is fixed by using a locking nut I after being sleeved in.

Further, a limiting sleeve is fixed between the actuator shell and the servo motor stator assembly.

Furthermore, the deep groove ball bearing is sleeved from the left side and then axially fixed by a positioning sleeve II and a locking nut II.

The left side of the actuator shell comprises a front end cover, the actuator shell is wrapped outside a rotor nut, a deep groove ball bearing, a double-box thrust bearing and a ball screw, one side of the actuator shell is fixed on a servo motor stator component, and the ball screw penetrates through the front end cover to be connected with the bolt component; one end of the limiting flange component is connected with the servo motor stator component, and the other end of the limiting flange component is connected with the external interface, so that the axial rotation freedom degree of the compact actuator can be limited.

Furthermore, the ball screw is provided with a plurality of raised lines along the axial direction, the front end cover is provided with a groove at the corresponding position, and the raised lines linearly move along the groove to control the ball screw to roll.

Furthermore, the raised strips and the matched grooves are arranged at 90 degrees.

Further, the bolt assembly comprises a limiting bolt head and a first joint bearing, the limiting bolt head comprises a limiting protrusion structure, the limiting bolt head is provided with an annular groove structure, and the first joint bearing is axially positioned with the limiting bolt head structure in a pressing annular groove deformation mode.

Furthermore, the limiting flange support assembly comprises a limiting flange support and a second oscillating bearing, the limiting flange support is provided with an annular groove structure, and the second oscillating bearing is axially fixed on the mounting hole of the limiting flange support in a pressing annular groove deformation mode.

The working principle is as follows: the motor rotor integrated with the screw nut rotates, the raised line structure on the ball screw is matched and interacted with the groove structure on the front end cover, the ball screw only has motion output in the axial linear direction, the structural transmission form of a coupler or a connecting key between the traditional motor and the screw is omitted, and the rotation of the actuator shell is limited through the limiting flange support structure. The compact structure of the actuator is greatly improved, and the manufacturability of machining and assembling of the structure is reduced. And when the same zero position length is achieved, the stroke of the actuator is improved by 20 percent.

The invention has the beneficial effects that:

(1) the utility model provides a structural style through two-way thrust bearing and deep groove ball bearing built-up connection makes the product can satisfy the axial and bears the weight of the requirement between servo motor and the actuator shell structure, avoids the actuator rotor to bear the axial float that the bearing force effect leads to. Meanwhile, the inertia is greatly reduced, and the design is very suitable for the scheme of a compact actuator.

(2) The actuator has the advantages that the stroke of the actuator is improved by 20% under the same zero position length, the structure is more compact, the occupied space is small, the assembly difficulty of products is reduced, and the assembly efficiency of the products is improved.

(2) The actuator is structurally characterized in that limiting devices are arranged on a traditional ball screw and a flange support assembly, a guide structure on the traditional screw is omitted, the processing manufacturability of the screw and a shell structure is improved, the cost is reduced, and the product integration level is improved.

Drawings

Fig. 1 and 2: a structure diagram of the electromechanical actuator;

the device comprises a bolt assembly 1, an actuator assembly 2, a limiting flange assembly 3, a ball screw 4, a rotor nut 5, a front end cover 6, a positioning sleeve I7, a servo motor stator assembly 8, a bidirectional thrust bearing 9, a deep groove ball bearing 10, a limiting sleeve 11, a locking nut I12, a positioning sleeve II 13 and a locking nut II 14;

FIG. 3: a structure diagram of the ball screw;

FIG. 4: front end cover structure diagram;

wherein, a groove matched with the ball screw is designed on the end cover;

FIG. 5: the lead screw and the front end cover are installed schematically;

FIG. 6: a schematic diagram (one) of a limiting flange assembly;

wherein: 31-a limiting flange support and 32-a joint bearing II;

FIG. 7: limit flange assembly sketch (II)

Detailed Description

In addition to the embodiments described below, the invention is capable of other embodiments or of being practiced or carried out in various ways. It is to be understood, therefore, that the invention is not limited in its application to the details of construction and the arrangements of the components set forth in the following description or illustrated in the drawings. While only one embodiment has been described herein, the claims are not to be limited to that embodiment.

As shown in fig. 1 and 2, a compact electromechanical actuator comprises a bolt assembly 1, an actuator shell 2, a limiting flange support assembly 3, a ball screw 4, a rotor nut 5, a servo motor stator assembly 8, a bidirectional thrust bearing 9 and a deep groove ball bearing 10; the right end of the ball screw 4 is matched with the rotor nut 5 for use, both sides of the rotor nut 5 are of a stepped shaft structure, the bidirectional thrust bearing 9 is sleeved from the left side, and then the two sides are respectively sleeved into the deep groove ball bearings 10; the deep groove ball bearing 10 and the bidirectional thrust bearing 9 are fixed in the servo motor assembly 8 and are axially fixed; the rotor nut 5 is used as a rotor of a servo motor, the motor is started, the inner side of the bidirectional thrust bearing 9 rotates, and the rotor nut 5 rotates under the support of the deep groove ball bearing 10 to drive the ball screw 4 to do linear reciprocating motion.

Threads are arranged on the outer side of the stepped shaft structure on the left side of the rotor nut 5, and the bidirectional thrust bearing is sleeved and fixed by a locking nut I; a limiting sleeve 11 is fixed between the actuator shell 2 and the servo motor stator assembly 8; the deep groove ball bearing 10 is sleeved from the left side and then axially fixed by a positioning sleeve II 13 and a locking nut II 14.

The left side of the actuator shell 2 comprises a front end cover 6, the actuator shell 2 is wrapped outside a rotor nut 5, a deep groove ball bearing 10 and a two-way thrust bearing 9, one side of the actuator shell is fixed on a servo motor stator assembly 8, and a ball screw 4 penetrates through the front end cover 6 to be connected with the bolt assembly 1; one end of the limiting flange component 4 is connected with the servo motor stator component 8, and the other end of the limiting flange component is connected with an external interface, so that the axial rotation freedom degree of the compact actuator is limited.

As shown in fig. 3-5, the ball screw is provided with a plurality of raised lines along the axial direction, the front end cover is provided with a groove at a corresponding position, and the raised lines move linearly along the groove to control the ball screw to roll; the ball screw and the mounting matching groove of the front end cover are arranged at 90 degrees.

The bolt assembly 1 comprises a limiting bolt head and a first oscillating bearing, the limiting bolt head comprises a limiting protrusion structure, the limiting bolt head is provided with an annular groove, and the first oscillating bearing is axially positioned with the limiting bolt head in a pressing annular groove deformation mode.

As shown in fig. 6, the limiting flange assembly 3 includes a limiting flange support 31 and a second oscillating bearing 32, the limiting flange support 31 has an annular groove structure, and the second oscillating bearing 32 is axially fixed on the mounting hole of the limiting flange support in a press-fitting annular groove deformation mode.

As shown in fig. 7, the limiting flange seat 31 has a limiting boss structure, which can prevent the rotational freedom between the seat and the mounting flange around the X-axis.

The working principle is as follows: the motor rotor integrated with the ball screw rotates to drive the ball screw to rotate, the protruding structure on the screw rod realizes linear displacement output of the ball screw through the matching effect with the groove of the front end cover, the structural transmission form of a coupler or a connecting key between the traditional motor and the screw rod is omitted, and meanwhile, the structural design of a guide post and a guide bearing on the traditional screw rod and the structural design of a long guide groove on a shell structure are omitted. The freedom degree of rotation of the actuator shell around the X direction of the mounting flange is limited through a limiting flange support structure. The compact structure of the actuator is greatly improved, and the manufacturability of machining and assembling of the structure is reduced. And when the same zero position length is achieved, the stroke of the actuator is improved by 20 percent.

Various modifications may be made to the method of the invention described above without departing from the scope of the invention, and the scope of protection should therefore be determined from the content of the appended claims.

Claims

1. A compact electromechanical actuator is characterized by comprising a ball screw, a rotor nut, a bidirectional thrust bearing, a deep groove ball bearing and a servo motor stator assembly; the right end of the ball screw is matched with a rotor nut, both sides of the rotor nut are of stepped shaft structures, a bidirectional thrust bearing is sleeved from the left side, and then the two sides of the bidirectional thrust bearing are sleeved into the deep groove ball bearings respectively; the deep groove ball bearing and the bidirectional thrust bearing are fixed in the servo motor assembly and are axially fixed; the rotor nut is used as an electric rotor of the servo motor, the motor is started, the inner side of the bidirectional thrust bearing rotates, and the rotor nut rotates to drive the ball screw to do linear reciprocating motion under the support of the deep groove ball bearing.

2. The compact electromechanical actuator of claim 1, wherein the outer side of the stepped shaft structure on the left side of the rotor nut is provided with threads, and the bidirectional thrust bearing is sleeved and fixed by a lock nut I.

3. The compact electro-mechanical actuator of claim 1, wherein a limit sleeve is secured between the actuator housing and the servo motor stator assembly.

4. The compact electromechanical actuator of claim 2, wherein the deep groove ball bearing is sleeved from the left side and then axially fixed using a positioning sleeve ii and a lock nut ii.

5. The compact electromechanical actuator of one of claims 1 to 4, further comprising a bolt assembly, a limiting flange assembly, and an actuator casing, wherein the left side of the actuator casing comprises a front end cover, the actuator casing is wrapped outside the rotor nut, the deep groove ball bearing, the double-box thrust bearing, and the ball screw, one side of the actuator casing is fixed on the servo motor stator assembly, and the ball screw penetrates through the front end cover to be connected with the bolt assembly; one end of the limiting flange component is connected with the servo motor stator component, and the other end of the limiting flange component is connected with the external interface, so that the axial rotation freedom degree of the compact actuator can be limited.

6. The compact electromechanical actuator of claim 5, wherein the ball screw has a plurality of ribs disposed axially, and the front cover has a plurality of grooves disposed at corresponding positions, the ribs moving linearly along the grooves to control the ball screw to roll.

7. The compact electromechanical actuator of claim 6, wherein the grooves into which the ribs engage are symmetrically disposed at 90 °.

8. The compact electromechanical actuator of claim 5, wherein the bolt assembly includes a limiting bolt head including a limiting protrusion structure, and a first joint bearing, the limiting bolt head being provided with an annular groove structure, and the first joint bearing being axially positioned with the limiting bolt head structure by press-fitting an annular groove deformation.

9. The compact electromechanical actuator of claim 5, wherein the limiting flange assembly comprises a limiting flange support and a second oscillating bearing, the limiting flange support has an annular groove structure, and the second oscillating bearing is axially fixed on the mounting hole of the limiting flange support in a press-fitting annular groove deformation mode.

10. The compact electro-mechanical actuator of claim 9, wherein the retainer flange carrier has a retainer boss structure thereon to prevent rotational freedom about the X-axis between the carrier and the mounting flange.