Pin gear housing, RV reducer, industrial robot

Abstract

The present invention provides a pinion housing, an RV reducer, and an industrial robot, belonging to the field of RV reducer design. The pinion housing includes a pinion housing body having an inner circular wall with a plurality of pinion holes formed thereon. The plurality of pinion holes are spaced apart circumferentially along the inner circular wall and extend axially through both ends of the pinion housing body along the inner circular wall. The inner circular wall is also provided with a first annular groove concentrically therewith, the depth of the first annular groove being greater than the depth of the pinion holes. The present invention reduces the concentration of iron filings in the internal grease after the reducer is in operation, and has a low probability of contact with the needle roller, thereby preventing the iron filings from being driven by the movement of the needle roller to diffuse between internal rotating friction components and causing increased wear of the components. The invention can also effectively prevent the occurrence of temperature rise due to the presence of wear debris, thereby increasing the service life.

Description

Technical Field

[0001] The present invention belongs to the field of RV reducer design, and in particular relates to a pinion gear housing, an RV reducer, and an industrial robot. Background Art

[0002] RV reducers are primarily used in the joints of industrial robots. As the scope and number of industrial robots increase, higher requirements are placed on the lifespan and stability of RV reducers. The internal structure of an RV reducer is primarily rigid. During operation, internal parts often come into direct, hard contact, resulting in significant friction. Due to the varying materials of the internal parts, component wear varies during friction, generating large amounts of iron filings and even debris on the surface of the parts. These scraps and debris follow the movement of internal parts and participate in the meshing of the entire machine, exacerbating wear between parts and causing further damage or even failure. Furthermore, the increased concentration of scraps can rapidly increase the temperature within the prototype, leading to excessive temperature rise, ultimately causing rapid prototype failure, robot shutdown, and even operational failure. Therefore, identifying the types of parts that experience early wear in RV reducers and optimizing the targeted treatment of these scraps can reduce reducer failures and significantly improve their operational stability, operating temperature control, and service life.

[0003] The pin-to-pinion meshing part of the RV reducer is mainly composed of a pin-tooth housing, a needle roller and a cycloidal wheel. Among them, the material of the pin-tooth housing is relatively soft and has poor wear resistance. During the operation of the reducer, the pin-tooth holes involved in the meshing will be worn first, and a large amount of wear iron chips will be generated. Because the interior of the reducer is all high-precision matching, including bearings and gear structures, when iron chips (metal grinding chips) impurities enter the precision meshing parts, it will cause accelerated wear of the meshing parts, excessive temperature rise, and even failure. Therefore, it is necessary to collect and process the initial wear iron chips, control them from the source, optimize the internal working conditions of the reducer, and improve the service life of the prototype. Based on this, the present invention is proposed. Summary of the Invention

[0004] Therefore, the present invention provides a pinion housing, an RV reducer, and an industrial robot, which can solve the technical problem that the grinding debris generated in the existing RV reducer cannot be collected in time, causing it to diffuse and transfer between the internal rotating meshing parts, exacerbating the wear of the reducer and excessive temperature rise.

[0005] In order to solve the above problems, the present invention provides a needle tooth housing, including a needle tooth housing body, the needle tooth housing body having an inner circular wall, a plurality of needle tooth holes constructed on the inner circular wall, the plurality of needle tooth holes are arranged at intervals along the circumference of the inner circular wall, and the needle tooth holes pass through both ends of the needle tooth housing body along the axial direction of the inner circular wall, and a first annular groove concentrically arranged therewith is also constructed on the inner circular wall, and the depth of the first annular groove is greater than the depth of the needle tooth hole.

[0006] In some embodiments, the first annular groove has a plurality of wear chip separation structures therein, and the plurality of wear chip separation structures are spaced apart along the circumferential direction of the first annular groove.

[0007] In some embodiments, the wear chip separation structure includes a column connected to the bottom wall of the first annular groove and a first separation arm at the free end of the column, and the first separation arm extends clockwise along the circumferential direction of the first annular groove to form a first wear chip accommodating space between the first separation arm and the bottom wall of the first annular groove.

[0008] In some embodiments, the free end of the column further has a second separation arm, which extends counterclockwise along the circumference of the first annular groove to form a second wear debris receiving space between the second separation arm and the bottom wall of the first annular groove.

[0009] In some embodiments, a wear debris adsorption structure is further provided in the first annular groove, and the wear debris adsorption structure is magnetic.

[0010] In some embodiments, the first annular groove is located in the middle region of the length of the needle tooth hole.

[0011] In some embodiments, a second annular groove is further configured on the inner circular wall and is arranged concentrically therewith. The second annular groove is located in the first end region of the length of the needle tooth hole and the depth of the second annular groove is less than the depth of the first annular groove.

[0012] In some embodiments, a third annular groove is further constructed on the inner circular wall and is arranged concentrically therewith. The third annular groove is located in the second end region of the length of the needle tooth hole and the depth of the third annular groove is less than the depth of the first annular groove.

[0013] The present invention also provides an RV reducer, comprising the above-mentioned pinion gear housing.

[0014] The present invention also provides an industrial robot comprising the above-mentioned RV reducer.

[0015] The pinion housing, RV reducer, and industrial robot provided by the present invention reduce the concentration of iron chips in the internal grease after the reducer is running, and have a low probability of contact with the needle roller, so that the iron chips will not be driven by the movement of the needle roller to spread between the internal rotating friction parts and cause increased wear of the parts. It can also effectively prevent the temperature increase caused by the presence of grinding chips and increase the service life. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 A longitudinal section of a pin tooth housing according to an embodiment of the present invention;

[0017] Figure 2 for Figure 1 A partial enlarged view of point A in the middle;

[0018] Figure 3 is a cross-section of a pinion housing according to an embodiment of the present invention;

[0019] Figure 4 for Figure 3 A partial enlarged view of point B in the middle;

[0020] Figure 5 Schematic diagram (cross section) of the internal structure of an RV reducer according to another embodiment of the present invention.

[0021] The reference numerals indicate:

[0022] 1. Needle gear housing body; 11. Needle gear hole; 21. First annular groove; 22. Grinding dust separation structure; 221. Column; 222. First separation arm; 223. Second separation arm; 23. Grinding dust adsorption structure; 31. Second annular groove; 32. Third annular groove; 41. Needle roller; 42. Cycloidal wheel; 43. Bearing outer ring. DETAILED DESCRIPTION

[0023] See also Figures 1 to 5As shown, according to an embodiment of the present invention, a pinion housing is provided, comprising a pinion housing body 1. The pinion housing body 1 has an inner circular wall with a plurality of pinion holes 11 formed therein. The plurality of pinion holes 11 are spaced apart along the circumference of the inner circular wall and extend axially through both ends of the pinion housing body 1. The inner circular wall also has a first annular groove 21 concentrically disposed therewith. When in use, the first annular groove 21 is filled with lubricating grease. The depth of the first annular groove 21 is greater than the depth of the pinion holes 11. In this technical solution, the depth of the first annular groove 21 is greater than the depth of the pinion holes 11, thereby forming a space for collecting and accommodating wear debris generated by internal rotating friction components. The generated wear debris is retained in this space, reducing the concentration of iron chips in the internal grease after the reducer is in operation. The generated wear debris is also less likely to contact the needle roller 41, thereby preventing the movement of the needle roller 41 from driving the iron chips to spread between the internal rotating friction components and causing increased wear of the components. Furthermore, the temperature rise caused by the presence of the wear debris is effectively prevented, thereby extending the service life.

[0024] As a preferred embodiment, see Figure 3 As shown, the first annular groove 21 has a plurality of wear chip separation structures 22, and the plurality of wear chip separation structures 22 are spaced apart along the circumferential direction of the first annular groove 21. The wear chip separation structures 22 can separate at least part of the wear chips mixed in the lubricating grease, and part of the lubricating grease after separation of the wear chips can be added to the matching positions of the needle roller 41, the needle tooth hole 11 and the cycloidal wheel 42 to achieve more sufficient lubrication and reduce wear. In a specific embodiment, the chip separation structure 22 includes a column 221 connected to the bottom wall of the first annular groove 21 and a first separation arm 222 at the free end of the column 221. The first separation arm 222 extends clockwise along the circumferential direction of the first annular groove 21 to form a first chip accommodating space between the first separation arm 222 and the bottom wall of the first annular groove 21. In this way, when the lubricating grease in the first annular groove 21 flows counterclockwise, the first separation arm 222 will be able to separate the chips mixed in the flowing grease, so that this part of the chips will remain in the first chip accommodating space, further reducing the adverse risk of the chips being driven to diffuse to the joint of the internal rotating friction component again. Furthermore, the free end of the column 221 also has a second separation arm 223, which extends counterclockwise along the circumferential direction of the first annular groove 21 to form a second wear chip accommodating space between the second separation arm 223 and the bottom wall of the first annular groove 21. The first wear chip accommodating space and the second wear chip accommodating space are respectively located on both sides of the circumference of the column 221, and can separate the wear chips in the flowing grease driven by different rotation directions.

[0025] As a preferred technical solution, a wear chip adsorption structure 23 is also provided in the first annular groove 21. The wear chip adsorption structure 23 is magnetic. For example, a plurality of permanent magnets are connected to the surface of the groove body of the first annular groove 21. In a preferred embodiment, the wear chip separation structure 22 is made of permanent magnets as a whole, and is connected to the bottom wall of the first annular groove 21 in a detachable manner. The aforementioned detachable manner can be specifically, for example, that the column 221 of the wear chip separation structure 22 has a T-shaped protrusion, which is inserted into the T-shaped slide groove located on the bottom wall of the first annular groove 21 through this T-shaped protrusion.

[0026] Specifically, the first annular groove 21 is located in the middle of the length of the needle tooth hole 11, which can be located exactly in the middle of the length, or it can be offset to a certain extent. In this case, the inner circular wall is also configured with a second annular groove 31 arranged concentrically therewith. The second annular groove 31 is located in the first end region of the length of the needle tooth hole 11, and the depth of the second annular groove 31 is less than the depth of the first annular groove 21, thereby collecting wear debris in the first end region. Preferably, the inner circular wall is also configured with a third annular groove 32 arranged concentrically therewith. The third annular groove 32 is located in the second end region of the length of the needle tooth hole 11, and the depth of the third annular groove 32 is less than the depth of the first annular groove 21, thereby collecting wear debris in the second end region. In this way, the first annular groove 21, the second annular groove 31, and the third annular groove 32 achieve wear debris collection within the length coverage range of the needle roller 41. At the same time, the first annular groove 21, the second annular groove 31, and the third annular groove 32 form a stepped structure of varying depths along the axial direction of the pin gear housing body 1, which allows for better deposition of iron chips and provides multiple channels for the flow of grease and iron chips.

[0027] In summary, the stepped structures of different depths (the first annular groove 21, the second annular groove 31 and the third annular groove 32) constructed in the needle gear housing body 1 of the present invention are provided with a chip separation structure 22. During the internal meshing operation, the chip separation structure 22 has a blocking effect, which can better restrict and collect the iron chips (i.e., the aforementioned chip). When the iron chips are transferred inward during the meshing process, the iron chips will gather in the annular grooves under the action of rotation. By collecting and blocking the flow of the iron chips and accumulating them in the grooves, the collection and control of the iron chips are achieved to prevent them from diffusing inwardly. The second annular groove 31 and the third annular groove 32 are formed by The combined effect of the upper and lower end faces of the needle hole 11 and the end faces of the upper and lower main bearing outer rings (bearing outer ring 43) restricts the flow direction of the iron chips, and then, through the action of rotation, the iron chips transferred to the two ends are collected and controlled in the second annular groove 31 and the third annular groove 32 to prevent them from spreading into the interior of the machine; under the action of rotation, the iron chips will be deposited at the bottom of the groove, which will reduce the concentration of iron chips in the grease inside the prototype, and the lubricating effect of the grease will be better maintained. At the same time, after the concentration of iron chips in the grease is reduced, its thermal conductivity and heat dissipation performance will be better. During the operation of the whole machine, the temperature rise change will be more stable, thereby increasing the service life of the whole machine.

[0028] At the same time, the first annular groove 21 , the second annular groove 31 and the third annular groove 32 have a grease storage function, providing sufficient grease at the meshing position to ensure sufficient lubrication between the cycloid wheel 42 , the needle roller 41 and the needle tooth hole 11 .

[0029] According to the embodiment of the present invention, see Figure 5 , also provides an RV reducer, including the above-mentioned pin gear housing.

[0030] According to an embodiment of the present invention, there is further provided an industrial robot comprising the above-mentioned RV reducer.

[0031] It is easy for those skilled in the art to understand that, under the premise of no conflict, the advantageous technical features of the above-mentioned methods can be freely combined and superimposed.

[0032] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention. The above are merely preferred embodiments of the present invention. It should be noted that those skilled in the art may make various improvements and variations without departing from the technical principles of the present invention, and such improvements and variations shall also be considered within the scope of protection of the present invention.

Claims

1. A needle tooth housing, comprising a needle tooth housing body (1), wherein the needle tooth housing body (1) has an inner circular wall, and a plurality of needle tooth holes (11) are constructed on the inner circular wall, wherein the plurality of needle tooth holes (11) are arranged at intervals along the circumference of the inner circular wall and the needle tooth holes (11) pass through both ends of the needle tooth housing body (1) along the axial direction of the inner circular wall, characterized in that: A first annular groove (21) is also constructed on the inner circular wall and is arranged concentrically therewith, and the depth of the first annular groove (21) is greater than the depth of the needle tooth hole (11); a plurality of wear chip separation structures (22) are provided in the first annular groove (21), and the plurality of wear chip separation structures (22) are arranged at intervals along the circumferential direction of the first annular groove (21); the wear chip separation structure (22) includes a column (221) connected to the bottom wall of the first annular groove (21) and a first separation arm (222) at the free end of the column (221), and the first separation arm (222) extends clockwise along the circumferential direction of the first annular groove (21) to form a first wear chip accommodating space between the first separation arm (222) and the bottom wall of the first annular groove (21).

2. The needle tooth housing according to claim 1, characterized in that: The free end of the column (221) also has a second separation arm (223), and the second separation arm (223) extends counterclockwise along the circumferential direction of the first annular groove (21) to form a second wear chip accommodating space between the second separation arm (223) and the bottom wall of the first annular groove (21).

3. The needle tooth housing according to claim 1, characterized in that A wear chip adsorption structure (23) is also provided in the first annular groove (21), and the wear chip adsorption structure (23) is magnetic.

4. The needle tooth housing according to claim 1, characterized in that The first annular groove (21) is located in the middle region of the length of the needle tooth hole (11).

5. The needle tooth housing according to claim 1, characterized in that: The inner circular wall is also provided with a second annular groove (31) arranged concentrically therewith. The second annular groove (31) is located in the first end region of the length of the needle tooth hole (11) and the depth of the second annular groove (31) is less than the depth of the first annular groove (21).

6. The needle tooth housing according to claim 5, characterized in that: The inner circular wall is also provided with a third annular groove (32) arranged concentrically therewith. The third annular groove (32) is located in the second end region of the length of the needle tooth hole (11) and the depth of the third annular groove (32) is less than the depth of the first annular groove (21).

7. An RV reducer, characterized in that: The needle tooth housing comprises the needle tooth housing according to any one of claims 1 to 6.

8. An industrial robot, characterized in that: Including the RV reducer as described in claim 7.

Images