High-precision gear driving device

Abstract

The utility model discloses a high-precision gear driving device which comprises a shell, a driving motor and an internal transmission system, the internal transmission system adopts a multi-stage parallel shaft gear transmission structure, an input stage adopts cylindrical gear transmission, an input stage gear pair backlash radial adjusting component is arranged at the input end of the input stage, and an output stage adopts variable tooth thickness gear transmission. An output-stage gear pair backlash axial flexible adjusting assembly is arranged in a hollow structure at one end of the output-stage variable-tooth-thickness pinion shaft; when the driving device cannot meet the transmission precision requirement due to assembly errors or tooth surface abrasion, the input stage can radially adjust the center distance of the gear pair of the input stage by rotating the radial adjusting component and changing the position angle of the screw hole set connected with the shell, and the output stage can adjust the center distance of the gear pair of the input stage through the axial flexible adjusting assembly. The backlash of the output stage gear pair can be automatically and elastically adjusted, so that transmission errors caused by improper assembly or tooth surface abrasion are eliminated or reduced, a driving device meets the precision requirement, and the service life is prolonged.

Description

Technical Field

[0001] This application belongs to the field of robot joint transmission, and in particular relates to a high-precision gear drive device for the end joint of a heavy-duty robot. Background Technology

[0002] Due to the specific and complex nature of their applications, robots typically require high transmission and positioning accuracy, while also having strict requirements for vibration and noise control. Therefore, strict control is needed on the precision of gears in each joint and the backlash of each gear pair to ensure the overall system's positional control accuracy and dynamic performance. Errors are unavoidable during gear machining and assembly. Furthermore, with increasing service life, gear teeth wear down, leading to reduced system precision and ultimately failing to meet usage requirements. To improve reliability and service life, two approaches are taken: firstly, improving machining processes and equipment to increase gear machining precision, which inevitably increases manufacturing difficulty and cost; secondly, designing backlash elimination and compensation structures to reduce the impact of errors and wear. Utility Model Content

[0003] The purpose of this application is to provide a high-precision gear drive device for robot end joints, which to a certain extent solves the technical problem that existing robot joint transmission systems fail to meet the requirements due to reduced precision caused by manufacturing errors, assembly errors, tooth surface wear, etc.

[0004] This application provides a high-precision gear drive device, which includes: an outer housing, a drive motor, and an internal transmission system, specifically:

[0005] The internal transmission system adopts a multi-stage parallel shaft gear transmission structure. The input stage uses a pair of cylindrical gears, and a radial adjustment component for the backlash of the input gear pair is provided at the input end of the input stage. The output stage uses a pair of variable tooth thickness gears, and one end of the variable tooth thickness pinion shaft of the output stage is a hollow structure, which houses an axial flexible adjustment component for the backlash of the output gear pair. By rotating the radial adjustment component, the input stage can adjust the center distance of the input gear pair radially, changing the position angle of the screw hole group connected to the housing. The output stage can automatically and elastically adjust the backlash of the output gear pair through the axial flexible adjustment component, thereby eliminating or reducing transmission errors caused by assembly or wear.

[0006] In the above technical solution, further, the distribution circles of the screw hole group connecting the outer ring of the input stage gear pair backlash radial adjustment component to the housing are concentric, the distribution circles of the screw hole group connecting the inner ring to the motor are concentric, and the axis of the inner ring and the outer ring of the input stage radial adjustment component are offset by a distance of 1-1.5mm.

[0007] The inner ring of the input stage radial adjustment component is interference-fitted with the outer ring of the input stage pinion shaft bearing. The input stage pinion shaft has an inner hole at its end, which is connected to the motor shaft via a flat key. After assembly, the axes of the input stage pinion shaft, the inner ring of the radial adjustment component, and the motor shaft are collinear.

[0008] In the above technical solution, the output stage of the internal transmission system further adopts a variable tooth thickness gear transmission, wherein the two ends of the variable tooth thickness pinion shaft are supported by separate cylindrical roller bearings, allowing bidirectional axial movement;

[0009] The output stage variable tooth thickness pinion shaft has a hollow structure at one end and is equipped with a gear pair backlash axial flexible adjustment component, which includes a bearing end cover, a threaded pin, a spring, and a ball.

[0010] The bearing end cover has an internal thread in the middle inner hole, and a stop is provided at the outer end of the internal thread. The structure is sealed by installing a seal at this point.

[0011] The threaded ejector pin shaft end is provided with a slotted groove and the outer circle of the shaft end is provided with an external thread, which forms a threaded pair with the internal thread of the bearing end cover; during installation, the threaded ejector pin is rotated by a flathead screwdriver to compress the spring, and the ball at the front end applies a certain degree of axial pressure to the variable tooth thickness gear pair.

[0012] The output stage variable tooth thickness large gear shaft adopts a cantilever structure, with an output flange and a set of connecting bolt holes on the gear web. It is directly connected to the load through bolts, making the structure more compact.

[0013] Beneficial effects

[0014] Compared with the prior art, the beneficial effects of this application are as follows:

[0015] The high-precision gear drive device provided in this application adopts a multi-stage parallel shaft gear transmission structure. The input stage uses cylindrical gear transmission, and a radial adjustment component for the gear pair backlash is provided at the input end of the input stage. The output stage uses variable tooth thickness gear transmission, and an axial flexible adjustment component for the gear pair backlash is provided in the hollow structure at one end of the pinion shaft of the output stage. When assembly defects or tooth surface wear cause the transmission accuracy of the drive device to fail to meet the usage requirements, the input stage can adjust the center distance of the input stage gear pair radially by rotating the radial adjustment component and changing the position angle of the screw hole group connected to the housing. The maximum adjustment amount can reach 2-3mm. The output stage can automatically and elastically adjust the backlash of the output stage gear pair through the axial flexible adjustment component. This eliminates or reduces the transmission error caused by assembly defects or tooth surface wear, improves the transmission accuracy of the drive device, and extends its service life. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the specific embodiments of this application or the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of the structure provided for an embodiment of this application;

[0018] Figure 2 The diagram shows the structure and working principle of the input-level radial component provided in the embodiments of this application (wherein, Figures a and b are structural diagrams of the adjustment component, and c, d, and e are schematic diagrams of the change of the inner circle center of the adjustment component when rotating 60°, 120°, and 180°, respectively).

[0019] Figure 3 A structural diagram of the output stage axial flexible adjustment assembly provided in this application embodiment;

[0020] Figure 4 This is a structural diagram of the bearing end cap provided in an embodiment of this application;

[0021] Figure 5 This is a structural diagram of the output stage variable tooth thickness large gear shaft provided in the embodiments of this application.

[0022] Figure label:

[0023] 1-Housing, 2-Radial adjustment component, 21-Outer ring, 22-Screw hole group, 23-Inner ring of adjustment component, 24-Screw hole group, 3-Drive motor, 31-Motor shaft, 4-Pinus shaft, 5-Self-aligning bearing, 6-Axial flexible adjustment component, 61-Bearing end cover, 611-Internal thread, 612-Sealing stop, 62-Threaded pin, 63-Spring, 64-Ball, 7-Seal, 8-Separable cylindrical roller bearing, 9-Variable tooth thickness pinion shaft, 10-Variable tooth thickness large gear shaft, 11-Load connecting bolt, 12-Load, 13-Large gear, 101-Output flange, 102-Screw hole group. Detailed Implementation Plan

[0024] The technical solutions of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are some embodiments of this application, but not all embodiments.

[0025] The components of the embodiments of this application described and shown in the accompanying drawings can be arranged and designed in a variety of different configurations. Therefore, the following detailed description of the embodiments of this application provided in the drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application.

[0026] Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0027] In the description of this application, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0028] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0029] The following reference Figures 1 to 5 The embodiments are described in detail to illustrate the technical solution of this utility model.

[0030] like Figure 1 As shown, the embodiments of this application provide a high-precision gear drive device. This high-precision gear drive device adopts a multi-stage parallel shaft gear transmission structure (this embodiment is a two-stage transmission, but it can also be a three-stage or four-stage transmission structure depending on the total transmission ratio). The input stage adopts a cylindrical gear transmission, including a pinion shaft 4 and a large gear 13 meshing with it. The pinion shaft 4 of the input stage is supported by a radial adjustment component 2 on the bearing 5. The outer ring 21 of the adjustment component is concentric with the distribution circle of the screw hole group 22 connecting to the housing. The inner ring 23 of the adjustment component is concentric with the distribution circle of the screw hole group 24 connecting to the motor. There is an eccentricity of 1-1.5mm between the inner and outer ring axes of the adjustment component. During assembly, the adjusting component 2 is connected to the housing through the screw hole group 22 and to the motor flange through the screw hole group 24; the inner ring 23 of the adjusting component is interference-fitted to the outer ring of the support bearing 5 of the input stage pinion shaft 4; the input stage pinion shaft 4 has an inner hole at its shaft end, which is connected to the motor shaft 31 through a flat key; after assembly, the axes of the input stage pinion shaft 4, the inner ring 23 of the adjusting component, and the motor shaft 31 are collinear.

[0031] like Figure 2As shown, when the input stage gear pair has excessive meshing backlash due to poor assembly or tooth surface wear, resulting in the system's transmission accuracy failing to meet working requirements, the radial adjustment of the center distance of the input stage gear pair can be achieved by rotating the adjusting component 2 and changing the position angle of the screw hole group 22 connected to the housing. Figures c), d), and e) show the changes in the axis of the inner ring 23 when the adjusting component 2 is rotated by 60°, 120°, and 180°, respectively, with a maximum change of 2-3 mm. Since the inner ring 23 of the adjusting component is collinear with the axis of the pinion shaft 4, the backlash of the input stage gear pair can be reduced by rotating the adjusting component 2, thereby eliminating or reducing the transmission error caused by assembly or tooth surface wear.

[0032] like Figure 1 and Figure 3 As shown, the output stage of the drive unit adopts a variable tooth thickness gear transmission, including a variable tooth thickness pinion shaft 9 and a variable tooth thickness large gear shaft 10 meshing with it. The pinion shaft 9 is supported at both ends by separable cylindrical roller bearings 8, allowing bidirectional axial movement. One end of the variable tooth thickness pinion shaft 9 is hollow, and an axial flexible adjustment component 6 is provided inside. This component includes a bearing end cover 61, a threaded pin 62, a spring 63, and a ball 64. The threaded pin 62 has a slotted groove at its shaft end and an external thread on its outer circumference, which forms a threaded pair with the internal thread 611 of the bearing end cover. During installation, the threaded pin 62 is rotated with a flathead screwdriver to compress the spring 63, and the ball 64 at the front end applies a certain degree of axial pressure to the output stage gear pair. When the backlash of the output stage gear pair increases due to poor assembly or tooth wear, the axial flexible adjustment component 6 can automatically and elastically adjust the backlash of the variable tooth thickness gear pair, thereby ensuring the good transmission accuracy requirements of the drive unit.

[0033] like Figure 4 As shown, in this embodiment, the bearing end cap 61 serves both to axially position the outer ring of the bearing and as an important support component for the axial flexible adjustment assembly. The central inner hole has an internal thread 611, which, together with the external thread at the shaft end of the threaded ejector pin 62, forms a threaded pair. By rotating the threaded ejector pin 62, the compression spring 63 axially presses against the variable tooth thickness gear pair. A stop 612 is provided at the outer end of the internal thread, where a sealing element 7 is installed to seal the structure.

[0034] like Figure 5 As shown, in this embodiment, the output stage variable tooth thickness large gear shaft 10 adopts a cantilever structure, and the web is provided with an output flange 101 and a bolt hole group 102. It is directly connected to the load 12 through the connecting bolt group 11, making the axial structure of the device more compact.

Claims

1. A high-precision gear drive device, characterized in that, It includes an outer casing (1), a drive motor (3), and an internal transmission system, specifically: The internal transmission system adopts a multi-stage parallel shaft gear transmission structure. The input stage adopts a pair of cylindrical gears, including a pinion shaft (4) and a large gear (13) meshing with it. A radial adjustment component (2) for the backlash of the input stage gear pair is provided at the input end of the input stage. The output stage adopts a pair of variable tooth thickness gears, including a variable tooth thickness pinion shaft (9) and a variable tooth thickness large gear shaft (10) meshing with it. One end of the variable tooth thickness pinion shaft (9) of the output stage is a hollow structure, and an axial flexible adjustment component (6) for the backlash of the output stage gear pair is provided inside. The input stage can adjust the center distance of the input stage gear pair radially by rotating the radial adjustment component (2) to change the position angle of the screw hole group (24) connected to the housing (1). The output stage automatically adjusts the backlash of the output stage gear pair elastically through the axial flexible adjustment component (6).

2. The high-precision gear drive device as described in claim 1, characterized in that, The outer ring (21) of the input stage gear pair backlash radial adjustment component (2) is concentric with the distribution circle of the first screw hole group (22) connected to the housing, and the inner ring (23) of the adjustment component is concentric with the distribution circle of the second screw hole group (24) connected to the motor. The axis of the inner ring (23) of the adjustment component and the outer ring (21) of the adjustment component are eccentric by 1-1.5mm.

3. The high-precision gear drive device as described in claim 2, characterized in that, The inner ring (23) of the input stage radial adjustment component is interference-fitted with the outer ring of the self-aligning bearing (5) of the input stage pinion shaft (4). The shaft end of the input stage pinion shaft (4) is provided with an inner hole, which is connected to the motor shaft (31) by a flat key. After assembly, the axes of the input stage pinion shaft (4), the inner ring (23) of the adjustment component and the motor shaft (31) are collinear.

4. The high-precision gear drive device as described in claim 1, characterized in that, The output stage of the internal transmission system adopts a variable tooth thickness gear transmission, including a variable tooth thickness pinion shaft (9) and a variable tooth thickness large gear shaft (10) meshing with it. The two ends of the variable tooth thickness pinion shaft (9) are supported by separate cylindrical roller bearings (8), allowing bidirectional axial movement.

5. A high-precision gear drive device as described in claim 4, characterized in that, One end of the output stage variable tooth thickness pinion shaft (9) is hollow, and an axial flexible adjustment component (6) is provided inside. The component includes a bearing end cover (61), a threaded pin (62), a spring (63), and a ball (64). During assembly, the output stage gear pair is axially pre-pressed by rotating the threaded pin (62) and compressing the spring (63).

6. A high-precision gear drive device as described in claim 5, characterized in that, The threaded ejector pin (62) has a slot at its shaft end and an external thread on the outer circle of its shaft end, which together with the internal thread (611) of the bearing end cover forms a threaded pair.

7. A high-precision gear drive device as described in claim 5, characterized in that, The bearing end cover (61) has an internal thread (611) in the middle inner hole, which forms a thread pair with the external thread at the shaft end of the threaded pin (62); in addition, the outer end of the internal thread (611) is provided with a sealing stop (612), and the structure is sealed by installing a sealing element (7).

8. A high-precision gear drive device as described in claim 4, characterized in that, The output stage variable tooth thickness large gear shaft (10) adopts a cantilever structure. An output flange (101) and a bolt hole group (102) are provided at the gear web. It is directly connected to the load (12) through the connecting bolt group (11).

Images