WO2018130154A1

WO2018130154A1 - High power mass density linear driving device of simplified structure

Info

Publication number: WO2018130154A1
Application number: PCT/CN2018/072085
Authority: WO
Inventors: 王兴兴; 杨知雨
Original assignee: 杭州宇树科技有限公司
Priority date: 2017-01-12
Filing date: 2018-01-10
Publication date: 2018-07-19
Also published as: DE212018000124U1; CN206313598U

Abstract

A high power mass density linear driving device (1) of a simplified structure, relating to the technical field of linear driving devices for robot joints. The device comprises a driving source used for supplying power, and a power conversion module (6) connected to the driving source. The driving source is an external rotor motor (7), and the power conversion module (6) comprises a ball screw nut (4) fixedly connected to a driving source rotation component, and a ball screw (3) in screw fitting with the ball screw nut (4). The driving source is an external rotor motor (7), and compared with an internal rotor motor, has a simple mechanical structure and wiring process, and high mass density in output torque. An internal space of a hollow shaft of the driving source rotation component is a part of the motion space of the ball screw (3), thereby greatly shortening the axial size of the entire driving device, and improving the integration level of the device.

Description

High-power mass density linear driving device with reduced structure

Technical field

The utility model relates to a linear drive device with high power mass density of a compact structure, belonging to the technical field of robot joint linear drive equipment.

Background technique

In the field of robotics, a wide variety of drive devices have been widely used. As robots increasingly require human-computer interaction and high motion performance, more requirements are placed on joint actuators, including: 1) Fast response, high power density, light weight, direct force control of robot joints; 2) simple structure and low cost, convenient for processing and manufacturing; 3) compact size of joint drive unit and improved space utilization of robots; 4) Stable and reliable.

At present, the typical ball screw nut drive unit structure is relatively complicated, the number of parts is large, the cost is high, the power quality density is low, the response speed is slow, and the size structure is not compact enough. Although some patents (such as CN201410135715) use a hollow shaft inner rotor motor, the ball screw passes through the hollow shaft of the motor, which improves the integration degree, but is limited by the complicated winding process of the inner rotor motor and the complicated and bulky mechanical structure. This structure is not suitable for high power mass density robotic joint drive units, but can only be applied to conventional industrial automation equipment. Due to the above shortcomings of typical ball screw nut drive units, ball screw nut drive systems are rarely used in robotic products today.

Utility model content

In view of the defects of the prior art, the object of the present invention is to provide a high-power mass density motor with a simplified mechanical structure, which is highly reliable and easy to maintain, and can be used for a linear driving device of a robot product. .

In order to achieve the above object, the technical solution of the present invention is:

A linear high-power mass density linear drive device comprising a drive source for providing power and a power conversion module fixedly coupled to a drive source rotating assembly, the drive source being an outer rotor motor including a core And a rotating component of the winding stator assembly and the sleeve setting subassembly, the power conversion module includes a ball screw nut fixedly coupled to the driving source rotating component, and a ball screw spirally engaged with the ball screw nut, the driving source The rotating component is a hollow shaft structure and is provided with a ball screw. The driving source used in the utility model is an outer rotor motor. Compared with the inner rotor motor, the mechanical structure and the winding process are simple, the output torque mass density is large, and the inner space of the hollow shaft of the rotating component of the driving source becomes the movement of the ball screw. The space greatly shortens the axial dimension of the entire drive unit and improves the integration of the device.

Further, the stator assembly of the driving source includes a stator core and a winding, and a stator base extending through the fixed stator core and the winding.

Further, the rotating assembly includes a rotor steel ring with an inner wall distributed with a permanent magnet group, a rotor base for fixed connection with the ball screw nut, and the rotor steel ring is fixedly connected coaxially with the rotor base, The rotor base has a rotating shaft, and the rotating shaft is a hollow shaft structure. The rotor base is coaxially mounted with the bearing 3 and the stator base to form a rotating pair, so that the rotating component and the stator assembly can be accurately matched; on the other hand, the hollow shaft structure of the rotating shaft of the rotor base is a ball wire. The bar provides axial movement space. The utility model mainly bears axial force during work. In the application where the axial force is not particularly large, the bearing one and the bearing three can directly bear the axial force. In the case where the axial force is relatively large, the additional thrust bearing 1 and the thrust bearing 2 are mainly used to bear the axial force of the present invention. The thrust flange is coaxially fixedly connected with the rotor base, and a coaxial line of the thrust bearing is placed between the stator base and the thrust flange; wherein the thrust end cover is fixedly connected with the stator base coaxial line, and the thrust bearing is disposed coaxially. Between the thrust flange and the thrust end cap. Therefore, when the rotating pair of the outer rotor motor of the present invention is subjected to the axial tensile force, it is mainly carried by the thrust bearing, and when subjected to the axial compressive force, it is assumed by the thrust bearing 2. The structure is simple and practical, the solution is practical and can be applied to various complex environments.

Further, the stator base is bored with a support disc, and the support disc is coaxially fixedly mounted with the rotor steel ring; the support disc forms a rotating pair through the bearing 2 and the stator base.

Further, the ball screw nut is directly fixedly connected to the rotor base or fixedly connected by the extender sleeve; the hollow shaft space of the rotating assembly and the inner space of the range extender constitute a part of the ball screw movement working space; The extended range sleeve can increase the working stroke space of the ball screw and is suitable for applications requiring large stroke applications.

Further, the hollow shaft of the rotating component passes through the thrust bearing 1 and the thrust bearing 2.

Further, the shaft end of the rotor base is provided with a shaft end retaining spring for preventing the axial movement of the rotor base and the stator base, and an electromagnetic brake for braking the support disc is fixed on the flange of the stator base end cover. . The driving source realizes braking and braking to the rotating component of the driving source through the electromagnetic brake, and the structure is simple and practical, and the technical solution is practical and feasible.

Further, the ball screw end portion is provided with a head seat for mounting and connecting the ball screw to the external device, and one end of the ball screw adjacent to the head seat is provided with a limiting block 1 , and the other end of the ball screw is provided with a limiting block 2 . The limiting block 1 and the limiting block 2 are made of an elastic material for defining an effective working space of the ball screw, and simultaneously for absorbing the impact energy of the ball screw moving to the limit position, reducing the ball screw movement. Noise and extend the life of the ball screw and the mating parts. A tailstock is fixed on the stator base for mounting connection with an external device.

Further, the driving source is connected to a driving control module for controlling rotation of the driving source, and the driving control module comprises an encoder magnet for collecting rotating component information and a corresponding magnetic encoder and for controlling rotation of the rotating component. Motor drive board. The magnetic encoder paired with the encoder magnet is fixedly mounted on the end cover flange of the stator base to realize the collection of the rotation angle of the rotating component of the outer rotor motor. The motor drive plate is fixed on the end cover flange of the stator base, and the motor drive plate may not be mounted on the end cover flange of the stator base, but only connected to the outer rotor motor through a wire. The technical solution can be selected according to the specific situation.

Compared with the prior art, the utility model has the following beneficial effects:

The driving source used in the utility model is an outer rotor motor. Compared with the inner rotor motor, the mechanical structure and the winding process are simple, the output torque mass density is large, and the inner space of the hollow shaft becomes a part of the movement space of the ball screw, which is greatly shortened. The axial dimension of the entire drive increases the integration of the device and the high power density.

The utility model has the advantages of simple structure and practical technical scheme, and adopts a ball screw nut linear driving unit, which has high reliability, low cost and easy maintenance, and is very suitable for a cooperative robot with rich human-computer interaction or a foot-like bionic mobile robot.

DRAWINGS

Figure 1 is a schematic view of the entire utility model;

Figure 2 is a cross-sectional view of the utility model;

Figure 3 is an exploded view of the present invention;

Figure 4 is an exploded view of the rotating assembly of the present invention;

Figure 5 is an exploded view of the stator assembly of the present invention;

Figure 6 is a cross-sectional view of an embodiment of the present invention including an extended range sleeve;

Figure 7 is a cross-sectional view showing an embodiment of a thrust bearing according to the present invention;

Figure 8 is an exploded view of an embodiment of the thrust bearing of the present invention;

Figure 9 is a cross-sectional view showing an embodiment of a thrust bearing including a range extender of the present invention;

Figure 10 is an application embodiment of the present invention.

Description of the reference signs:

1-Linear drive, 2-limit block one, 3-ball screw, 4-ball screw nut, 5-position block two, 6-power conversion module, 7-outer rotor motor, 8-axis end card Spring, 9-tailstock, 10-motor drive plate, 11-rotor base, 12-encoder magnet, 13-rotor rim, 14-permanent magnet set, 15-bearing one, 16-stator core and winding, 17-bearing two, 18-support plate, 19-electromagnetic brake, 20-stator base, 21-bearing three, 22-extended range, 23-uplink, 24-down link, 31-head, 32 - Thrust flange, 33-thrust bearing one, 34-thrust bearing two, 35-thrust end cap.

detailed description

In order to make the objects, technical solutions and advantages of the present invention more comprehensible, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It is understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

Rather, the invention is to cover any alternatives, modifications, and equivalents of the embodiments of the invention. Further, in order to provide a better understanding of the present invention, the specific details are described in detail in the following detailed description of the invention. The invention may be fully understood by those skilled in the art without a description of these details.

1 to 5, a high-power mass density linear driving device of a reduced structure, comprising a driving source for supplying power, a power conversion module 6 fixedly connected to the driving source rotor base 11, and Drive control module for driving and controlling the motor.

The drive source is an outer rotor motor that includes a stator assembly and a rotating assembly. The rotating assembly includes a rotor base 11, a rotor steel ring 13, and a permanent magnet group 14. The rotor base 11 is coaxially mounted with the stator base 20 via a bearing 15 and a bearing 31 to form a rotating pair. The rotor base 11 is fixedly coupled to the ball screw nut 4. The rotor rim 13 is coaxially fixedly connected to the rotor base 11 and the permanent magnet group 14 is distributed on the inner wall of the rotor rim 13 . The shaft end of the rotor base 11 is provided with a shaft end retainer 8 for preventing the rotor base 11 and the stator base 20 from axially swaying.

The stator assembly includes a bearing 15, a stator core and a winding 16, a bearing 17, a support disk 18, an electromagnetic brake 19, a stator base 20, a bearing three 21, and a tailstock 9. The stator base 20 is bored with a support plate 18 that is mounted coaxially with the rotor rim 13 . The support disk 18 forms a rotating pair with the stator base 20 via a bearing two 17. An electromagnetic brake 19 for braking the support disk 18 is fixed to the end cover flange of the stator base 20. The electromagnetic brake 19 achieves brake braking of the entire outer rotor motor by braking the support disk 18. The tailstock 9 is fixedly coupled to the stator base 20 for mounting connection with an external device.

The driving source used in the utility model is an outer rotor motor. Compared with the inner rotor motor, the mechanical structure and the winding process are simple, and the output torque mass density is large.

The power conversion module 6 includes a ball screw nut 4 fixedly coupled to the rotating assembly, and a ball screw 3 spirally engaged with the ball screw nut 4, the ball screw 3 and the ball screw nut 4 forming a spiral pair. The power conversion module 6 converts the rotational motion of the motor into a linear motion of the ball screw. The rotating component is a hollow shaft structure and sleeves a ball screw 3, and the inner space of the hollow shaft of the rotating component becomes a moving space of the ball screw 3, which greatly shortens the axial dimension of the entire driving device and improves the integration degree of the device. . A headstock 31 for mounting and connecting with an external device is fixed to the end of the ball screw 3. The ball screw 3 is provided with a stopper block 2 at one end of the headstock 31, and a limiting block 2 is provided at the other end of the ball screw 3. The limiting block 2 and the limiting block 2 are made of an elastic material for defining an effective working space of the lead screw and simultaneously for absorbing the impact energy when the screw moves to the limit position.

The drive control module includes an encoder magnet 12 for collecting rotational component information, a magnetic encoder corresponding to the encoder magnet 12, and a motor drive plate 10 for controlling the outer rotor motor 7. The magnetic encoder paired with the encoder magnet 12 is fixedly mounted on the end cover flange of the stator base 20 to realize the collection of the rotation angle of the rotating component of the outer rotor motor. The motor driving plate 10 is fixed on the end cover flange of the stator base 20, and the motor driving plate 10 may not be mounted on the end cover flange of the stator base 20, but only through the wire and the outer rotor. The motors are connected. The drive control module realizes closed-loop control of the motor according to the magnetic encoder on the motor, and controls the motor to realize real-time response according to an external control command. The drive control module receives an external control signal to control the position, speed, and output torque of the motor.

As shown in FIG. 6 , the present invention includes an extension sleeve embodiment. The effective stroke of the ball screw 3 is approximately equal to the length of the through shaft of the motor rotating assembly. In some special applications, if the stroke of the ball screw 3 needs to be increased. The extender sleeve 22 can be added between the ball screw nut and the rotor base 11 to increase the stroke, and the stroke of the driving device can be adjusted by adapting the extension sleeves 22 of different lengths.

As shown in FIG. 7, the utility model includes a thrust bearing embodiment, and the utility model mainly bears axial force during operation. In applications where the axial force is not particularly large, in the solution of Figure 2 described above, the bearing 15 and the bearing 3 21 can directly receive the axial force. In the case where the axial force is relatively large, as shown in Figs. 8 and 9, the additional thrust bearing 33 and the thrust bearing 2 are used to mainly bear the axial force of the present invention. The thrust flange 32 is coaxially fixedly coupled to the rotor base 11, and the thrust bearing 33 is coaxially disposed between the stator base 20 and the thrust flange 32. The thrust end cover 35 is coaxially fixedly coupled to the stator base 20, and the thrust bearing two 34 is coaxially disposed between the thrust flange 32 and the thrust end cover 35. Thus, when the rotating pair of the outer rotor motor 7 of the present invention is subjected to the axial tensile force, it is mainly carried by the thrust bearing 33, and when subjected to the axial compressive force, it is carried by the thrust bearing 234. The range extender and thrust bearing can also be used as shown in Figure 9.

As shown in FIG. 10, the utility model relates to an application embodiment: the utility model combines the connecting rod and the joint of the actual robot body to form a complete robot joint driving unit. The headstock 31 of the linear drive unit 1 is hinged to the upper link 23, and the tailstock 9 is hinged to the lower link 24. The rotating joint between the upper link 23, the lower link 24, the upper link 23 and the lower link 24 and the present invention together form a complete robot joint. By controlling the rotation of the rotating assembly of the present invention, the telescopic movement of the ball screw 3 is driven, thereby realizing the control of the rotational motion of the entire robot joint.

The above is only the preferred embodiment of the present invention, and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the present invention. The scope of protection of utility models.

Claims

A linear high-power mass density linear driving device comprising a driving source for supplying power and a power conversion module (6) rotatably connected to a driving source, wherein the driving source is an outer rotor motor, The utility model comprises a stator assembly with a core and a winding, a rotating assembly of a sleeve setting subassembly, the power conversion module (6) comprising a ball screw nut (4) fixedly connected with the rotating component, and a ball screw nut ( 4) A spirally matched ball screw (3), which is a hollow shaft structure and is provided with a ball screw (3).
A linear high power mass density linear drive apparatus according to claim 1, wherein said stator assembly comprises a stator core and a winding (16) and a stator extending through the stator core and the winding (16) Base (20).
A linear high-power-density linear driving device according to claim 2, wherein said rotating assembly comprises a rotor steel ring (13) having a permanent magnet group disposed on an inner wall thereof for use with a ball screw The nut (4) is fixedly connected to the rotor base (11), and the rotor steel ring (13) is fixedly connected coaxially with the rotor base (11).
A linear high power mass density linear drive apparatus according to claim 3, wherein said rotor base (11) passes through a bearing (15) and a bearing three (21) and a stator base ( 20) The coaxial axes are mounted together to form a rotating pair.
A linear high-power-density linear drive device according to claim 4, wherein said stator base (20) is provided with a support disk (18), said support disk (18) and The rotor rim (13) is coaxially fixedly mounted; the support disk (18) forms a rotating pair through the bearing two (17) and the stator base (20).
A high-power mass density linear driving device according to claim 5, characterized in that the ball screw nut (4) is directly fixedly connected to the rotor base (11) or passes through the extender sleeve (22). The fixed connection; the hollow shaft space of the rotating assembly and the inner space of the range extender (22) constitute a part of the moving working space of the ball screw (3).
A linear high-power-density linear driving device according to claim 6, wherein said rotating component hollow shaft is provided with a thrust bearing (33) and a thrust bearing two (34), said thrust The bearing one (33) is coaxially placed between the stator base (20) and the thrust flange (32); the thrust bearing two (34) is coaxially placed on the thrust flange (32) and the thrust end cover (35) between.
A high-power mass density linear driving device according to any one of claims 1-7, characterized in that the stator base (20) end cover flange is fixed with a brake support disk (18) Electromagnetic brakes (19).
A linear high-power-density linear driving device according to any one of claims 1 to 7, characterized in that the end of the ball screw (3) is fixed with a header (31) attached to an external device. The ball screw (3) is provided with a limiting block one (2) at one end of the adjacent headstock (31), and a limiting block 2 (5) at the other end of the ball screw (3); the stator base 20 is fixed on the stator There is a tailstock 9 for mounting with an external device.
A linear high-power-density linear drive device according to claim 9, wherein said drive source is coupled to a drive control module for controlling rotation of the drive source, and said drive control module includes An encoder magnet (12) for collecting rotational component information and a corresponding magnetic encoder and a motor drive plate (10) for controlling rotation of the rotary assembly.