Two-layer roller rolling oscillating tooth speed reducer with four rows of cylindrical roller bearings

Abstract

The utility model discloses a two-layer roller rolling oscillating tooth speed reducer with four rows of cylindrical roller bearings, which comprises an inner gear ring assembly, an oscillating tooth frame assembly, an eccentric shaft assembly and an oscillating tooth assembly, the inner gear ring assembly comprises a front inner gear ring, a spacer sleeve and a rear inner gear ring, and the front inner gear ring and the rear inner gear ring are respectively arranged on two sides of the spacer sleeve; the movable tooth frame assembly comprises a front movable tooth frame, a middle movable tooth frame and a rear movable tooth frame, the front movable tooth frame and the rear movable tooth frame are arranged on the two sides of the middle movable tooth frame respectively, and the middle movable tooth frame is arranged on the inner side of the front inner gear ring and the inner side of the rear inner gear ring in a matched mode. And the front oscillating tooth frame and the rear oscillating tooth frame are rotatably arranged in inner cavities of the corresponding front inner gear ring and the rear inner gear ring respectively. According to the utility model, higher rotation precision can be ensured during output of the oscillating tooth carrier assembly, and higher supporting precision of the eccentric shaft base body is also ensured, so that the overall transmission precision of the speed reducer is improved, and the speed reducer can be used for replacing a numerical control rotary table of an existing numerical control machine tool.

Description

Technical Field

[0001] The utility model relates to the technical field of speed reducers, in particular to a two-layer roller rolling movable tooth speed reducer with four-row cylindrical roller bearings. Background Technique

[0002] At present, the commonly used robot joint speed reducers mainly include RV speed reducers and harmonic speed reducers. The harmonic speed reducer consists of three main components: a rigid gear, a flexible gear, and a wave generator, and uses a crossed roller bearing with a sealing property as the main support bearing, featuring a compact structure and is mainly used in occasions with high requirements for volume and noise. However, the harmonic speed reducer has some theoretical defects: 1) The alternating stress generated due to the periodic deformation of the flexible gear makes it prone to fatigue failure; 2) The number of simultaneously contacting teeth of the harmonic speed reducer is small, only 20 - 25% of the total number of teeth, so the transmission stiffness is low; 3) Due to the sliding friction between the flexible gear and the internal gear, the transmission efficiency is low, generally about 70%; since too large teeth are prone to stress concentration, the gear thickness cannot be designed too large and the transmission ratio cannot be too small, which severely limits the application range of this speed reducer. As shown in Figure 1 the harmonic speed reducer shown, mainly uses a roller crossed bearing with a sealing property to improve the transmission accuracy and load-bearing capacity of the harmonic speed reducer.

[0003] The RV speed reducer mainly includes a first-stage planetary reduction mechanism and a second-stage cycloid reduction mechanism. The RV speed reducer of a certain company mainly uses angular contact bearings for support, as shown in Figure 2 shown;

[0004] The RV speed reducer has advantages such as a large transmission ratio range, large torsional rigidity, and large load-bearing capacity compared with the harmonic speed reducer. However, the RV speed reducer also has the following problems: 1) There is a sliding friction link between the pin teeth and the pin tooth housing of the RV speed reducer, resulting in low transmission efficiency and easy loss of transmission accuracy due to wear, and high requirements for the material and heat treatment of the pin tooth housing; 2) The eccentric shaft of this speed reducer adopts an offset structure, the bearing diameter on the eccentric shaft is small, and the pressure angle is very large, close to 90 degrees at some angular positions, so the bearing load is large and the eccentric bearing is prone to failure; 3) The contact between the pin teeth and the cycloid gear of this speed reducer is a rigid contact. Although the overload capacity is large, due to the too high rigidity of the pin teeth, it is difficult to achieve load sharing, so high requirements are put forward for the machining accuracy of internal parts and the technical threshold is high.

[0005] Based on this, we have developed a two-layer roller rolling movable tooth speed reducer with four-row cylindrical roller bearings. Content of the Utility Model

[0006] The object of the present utility model is to overcome the above problems or at least partially solve the above problems, and to propose a two-layer roller rolling movable tooth reducer with four-row cylindrical roller bearings.

[0007] To achieve the above object, the present utility model adopts the following technical solutions: A two-layer roller rolling movable tooth reducer with four-row cylindrical roller bearings, comprising: an internal gear ring assembly, a movable tooth rack assembly, an eccentric shaft assembly and a movable tooth assembly.

[0008] The internal gear ring assembly includes a front internal gear ring, a spacer sleeve and a rear internal gear ring, and the front internal gear ring and the rear internal gear ring are respectively arranged on both sides of the spacer sleeve.

[0009] The movable tooth rack assembly includes a front movable tooth rack, a middle movable tooth rack and a rear movable tooth rack. The front movable tooth rack and the rear movable tooth rack are respectively arranged on both sides of the middle movable tooth rack. The middle movable tooth rack is adaptively arranged inside the front internal gear ring and the rear internal gear ring. The front movable tooth rack and the rear movable tooth rack can respectively rotate and are arranged in the inner cavities of the corresponding front internal gear ring and rear internal gear ring.

[0010] The eccentric shaft assembly includes an eccentric shaft base body, a front exciter bearing, a rear exciter bearing, a front exciter and a rear exciter. The eccentric shaft base body is movably arranged in the front movable tooth rack and the rear movable tooth rack. The outer walls on both sides of the eccentric shaft base body are respectively provided with a front exciter and a rear exciter. The front exciter bearing and the rear exciter bearing are respectively arranged on two eccentric circles with the same eccentricity but a 180-degree angular difference on the eccentric shaft base body located inside the front exciter and the rear exciter.

[0011] The movable tooth assembly is arranged between the front internal gear ring and the front exciter and between the rear internal gear ring and the rear exciter. The movable tooth assembly includes an outer core shaft, an inner core shaft, a movable tooth collar and a needle roller. The outer walls at both ends of the inner core shaft and the outer core shaft are respectively provided with a movable tooth collar, and a needle roller is arranged between the movable tooth collar and the inner core shaft and the outer core shaft.

[0012] In a preferred embodiment, positioning pin holes with an angular difference of 180 degrees are respectively formed on the outer circumferences of the front internal gear ring and the rear internal gear ring. A first positioning pin is arranged in the positioning pin hole. A first connecting screw is also tightened on the outer sides of the front internal gear ring and the rear internal gear ring. The inner ends of the first connecting screw and the first positioning pin are both connected to the spacer sleeve.

[0013] In a preferred embodiment, a second connecting screw is tightened on the outer circumferences of the front movable tooth rack and the rear movable tooth rack. A second positioning pin is also arranged on the outer sides of the front movable tooth rack and the rear movable tooth rack. The inner ends of the second connecting screw and the second positioning pin are both connected to the middle movable tooth rack.

[0014] In a preferred embodiment, eccentric shaft front bearings and eccentric shaft rear bearings are respectively arranged in a circumferential array between the outer walls on both sides of the eccentric shaft base body and the front movable tooth frame and the rear movable tooth frame.

[0015] In a preferred embodiment, seals are arranged between the front internal gear ring and the front movable tooth frame and between the rear internal gear ring and the rear movable tooth frame.

[0016] In a preferred embodiment, thrust rollers are arranged between both sides of the middle movable tooth frame and the front internal gear ring and the rear internal gear ring.

[0017] In a preferred embodiment, radial rollers are arranged between the front internal gear ring and the front movable tooth frame and between the rear internal gear ring and the rear movable tooth frame, and the radial rollers are located inside the seals.

[0018] In a preferred embodiment, the eccentric shaft assembly further includes a front spacer for the movable tooth frame, a spacer for the excitator, and a rear spacer for the movable tooth frame. The front spacer for the movable tooth frame is arranged between the front movable tooth frame and the front excitator, the spacer for the excitator is arranged between the front excitator and the rear excitator, and the rear spacer for the movable tooth frame is arranged between the rear excitator and the rear movable tooth frame.

[0019] Compared with the prior art, the present utility model provides a two-layer roller rolling movable tooth speed reducer with four-row cylindrical roller bearings. Through the thrust rollers and the radial rollers, the movable connection between the internal gear ring assembly and the movable tooth frame assembly can be realized. Through the eccentric shaft front bearing and the eccentric shaft rear bearing, the movable connection between the eccentric shaft base body and the movable tooth frame assembly is realized. The front excitator is supported by the front excitator bearing and the rear excitator is supported by the rear excitator bearing, so that when the movable tooth frame assembly outputs, it has higher rotational accuracy and also ensures that the eccentric shaft base body has higher support accuracy, thereby improving the overall transmission accuracy of the speed reducer and can be used to replace the existing numerical control turntable of a numerical control machine tool. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 is a schematic structural diagram of a harmonic speed reducer;

[0021] Figure 2 is a schematic structural diagram of an angular contact bearing RV speed reducer;

[0022] Figure 3 is a front view cross-sectional view of the present utility model;

[0023] Figure 4 is a side view cross-sectional view of the present utility model;

[0024] Figure 5 is a front view cross-sectional view of the internal gear ring assembly in the present utility model;

[0025] Figure 6 is a side view of the internal gear ring assembly in the present utility model;

[0026] Figure 7 This is the front view sectional view of the movable tooth frame assembly in the present utility model;

[0027] Figure 8 This is the side view of the movable tooth frame assembly in the present utility model;

[0028] Figure 9 This is the front view sectional view of the eccentric shaft assembly in the present utility model;

[0029] Figure 10 This is the side view sectional view of the eccentric shaft assembly in the present utility model;

[0030] Figure 11 This is the front view sectional view of the movable tooth assembly in the present utility model.

[0031] In the figure: 1. Inner gear ring assembly; 101. Front inner gear ring; 102. Spacer sleeve; 103. Rear inner gear ring; 104. Connecting screw one; 105. Positioning pin one; 2. Movable tooth frame assembly; 201. Front movable tooth frame; 202. Middle movable tooth frame; 203. Rear movable tooth frame; 204. Connecting screw two; 205. Positioning pin two; 3. Eccentric shaft assembly; 301. Eccentric shaft base; 302. Front eccentric shaft bearing; 303. Rear eccentric shaft bearing; 304. Front shock wave bearing; 305. Rear shock wave bearing; 306. Front shock wave; 307. Rear shock wave; 308. Front spacer sleeve of movable tooth frame; 309. Shock wave spacer sleeve; 310. Rear spacer sleeve of movable tooth frame; 4. Movable tooth assembly; 401. Outer core shaft; 402. Inner core shaft; 403. Movable tooth sleeve; 404. Needle roller; 5. Sealing member; 6. Thrust roller; 7. Radial roller. Specific embodiments

[0032] The following further elaborates on the present utility model in conjunction with the attached drawings.

[0033] This specific embodiment merely explains the present utility model and does not limit it. Those skilled in the art can make modifications that contribute creatively to this embodiment as needed after reading this description, but as long as they are within the scope of the claims of the present utility model, they are protected by the patent law.

[0034] A two-layer roller rolling movable tooth speed reducer of the present utility model with four-row cylindrical roller bearings solves the technical problems in the prior art. The general idea is as follows:

[0035] Embodiment 1:

[0036] Refer to Figures 3 - 11 ; A two-layer roller rolling movable tooth speed reducer with four-row cylindrical roller bearings, comprising: an inner gear ring assembly 1, a movable tooth frame assembly 2, an eccentric shaft assembly 3, and a movable tooth assembly 4,

[0037] The internal gear ring assembly 1 includes a front internal gear ring 101, a spacer sleeve 102, and a rear internal gear ring 103. The front internal gear ring 101 and the rear internal gear ring 103 are respectively arranged on both sides of the spacer sleeve 102;

[0038] The oscillating tooth carrier assembly 2 includes a front oscillating tooth carrier 201, a middle oscillating tooth carrier 202, and a rear oscillating tooth carrier 203. The front oscillating tooth carrier 201 and the rear oscillating tooth carrier 203 are respectively arranged on both sides of the middle oscillating tooth carrier 202. The middle oscillating tooth carrier 202 is adaptively arranged inside the front internal gear ring 101 and the rear internal gear ring 103. The front oscillating tooth carrier 201 and the rear oscillating tooth carrier 203 can respectively rotate and are arranged in the inner cavities of the corresponding front internal gear ring 101 and rear internal gear ring 103. Among them, the side surfaces of the square grooves for the movement of the rolling elements on both sides of the middle oscillating tooth carrier 102 should maintain good coplanarity characteristics, and the non-coplanarity error generally should not be greater than 0.02 mm;

[0039] The eccentric shaft assembly 3 includes an eccentric shaft base 301, a front exciter bearing 304, a rear exciter bearing 305, a front exciter 306, and a rear exciter 307. The eccentric shaft base 301 is movably arranged in the front oscillating tooth carrier 201 and the rear oscillating tooth carrier 203. The front exciter 306 and the rear exciter 307 are respectively arranged on both outer walls of the eccentric shaft base 301. The front exciter bearing 304 and the rear exciter bearing 305 are respectively arranged on two eccentric circles with the same eccentricity but a 180-degree angular difference on the eccentric shaft base 301 located inside the front exciter 306 and the rear exciter 307;

[0040] The oscillating tooth assembly 4 is arranged between the front internal gear ring 101 and the front exciter 306 and between the rear internal gear ring 103 and the rear exciter 307. The oscillating tooth assembly 4 includes an outer core shaft 401, an inner core shaft 402, an oscillating tooth sleeve 403, and needle rollers 404. Oscillating tooth sleeves 403 are arranged at both ends of the outer walls of the inner core shaft and the outer core shaft. Needle rollers 404 are arranged between the oscillating tooth sleeve 403 and the inner core shaft 402 and the outer core shaft 401.

[0041] During specific implementation, positioning pin holes with an angular difference of 180 degrees are respectively opened on the outer circumferences of the front internal gear ring 101 and the rear internal gear ring 103, which are used for combined grinding of the two internal gear rings and rotating one internal gear ring by 180 degrees after grinding to ensure a reasonable positional accuracy relationship between the internal gear ring, the oscillating tooth carrier, and the eccentric shaft and to achieve dynamic balance. A positioning pin 105 is arranged in the positioning pin hole. A connecting screw 104 is also tightened on the outer sides of the front internal gear ring 101 and the rear internal gear ring 103. The inner ends of the connecting screw 104 and the positioning pin 105 are both connected to the spacer sleeve 102.

[0042] During specific implementation, connecting screws II 204 are tightened on the outer circumferences of the front movable tooth frame 201 and the rear movable tooth frame 203. A positioning pin II 205 is also arranged on the outer sides of the front movable tooth frame 201 and the rear movable tooth frame 203. The inner ends of the connecting screws II 204 and the positioning pin II 205 are both connected to the middle movable tooth frame 202.

[0043] During specific implementation, eccentric shaft front bearings 302 and eccentric shaft rear bearings 303 are respectively arranged in a circumferential array between the outer walls on both sides of the eccentric shaft base body 301 and the front movable tooth frame 201 and the rear movable tooth frame 203.

[0044] During specific implementation, seals 5 are arranged between the front internal gear ring 101 and the front movable tooth frame 201 and between the rear internal gear ring 103 and the rear movable tooth frame 203.

[0045] During specific implementation, thrust rollers 6 are arranged between both sides of the middle movable tooth frame 202 and the front internal gear ring 101 and the rear internal gear ring 103.

[0046] During specific implementation, radial rollers 7 are arranged between the front internal gear ring 101 and the front movable tooth frame 201 and between the rear internal gear ring 103 and the rear movable tooth frame 203. The radial rollers 7 are located inside the seals 5.

[0047] During specific implementation, the eccentric shaft assembly 3 further includes a movable tooth frame front spacer 308, an exciter spacer 309, and a movable tooth frame rear spacer 310. The movable tooth frame front spacer 308 is arranged between the front movable tooth frame 201 and the front exciter 306. The exciter spacer 309 is arranged between the front exciter 306 and the rear exciter 307. The movable tooth frame rear spacer 310 is arranged between the rear exciter 307 and the rear movable tooth frame 203, and they jointly act to ensure that the front exciter 306 and the rear exciter 307 have definite movement positions.

[0048] During operation, the internal gear ring assembly 1 is usually fixed on the rotary table base of the machine tool. The eccentric shaft assembly 3 is connected to a torque motor or a general servo motor. The torque motor or the general servo motor drives the eccentric shaft assembly to perform a relatively high-speed rotational movement. After deceleration by the movable tooth assembly 4, the movement is transmitted to the movable tooth frame assembly to achieve speed reduction and torque amplification. At the same time, this reducer can also adopt the movement form of fixing the movable tooth frame and outputting through the internal gear ring, and can be used for various indexing mechanisms and the numerical control rotary tables of machine tools.

[0049] The above description of the embodiments is for the convenience of those of ordinary skill in the art in this technical field to understand and use the present invention. Those who are familiar with the technology in this field can obviously make various modifications to the embodiments easily, and apply the general principles described herein to other embodiments without creative labor. Therefore, the present invention is not limited to the above embodiments. The improvements and modifications made by those skilled in the art according to the disclosure of the present invention without departing from the scope of the present invention should be within the protection scope of the present invention.

Claims

1. A two-layer roller rolling movable tooth reducer with four-row cylindrical roller bearings, characterized in that: Included are: An inner gear ring assembly (1), the inner gear ring assembly (1) comprising a front inner gear ring (101), a spacer sleeve (102) and a rear inner gear ring (103), wherein the front inner gear ring (101) and the rear inner gear ring (103) are respectively arranged on two sides of the spacer sleeve (102); A movable gear rack assembly (2), the movable gear rack assembly (2) comprising a front movable gear rack (201), a middle movable gear rack (202) and a rear movable gear rack (203), the front movable gear rack (201) and the rear movable gear rack (203) being respectively arranged on both sides of the middle movable gear rack (202), the middle movable gear rack (202) being adapted to be arranged on the inner sides of the front inner gear ring (101) and the rear inner gear ring (103), the front movable gear rack (201) and the rear movable gear rack (203) being respectively rotatably arranged on the corresponding front inner gear ring (101) and the rear inner gear ring (103) In the inner cavity, a seal (5) is provided between the front inner gear ring (101) and the front movable gear frame (201) and between the rear inner gear ring (103) and the rear movable gear frame (203); thrust rollers (6) are provided between the two sides of the middle movable gear frame (202) and the front inner gear ring (101) and the rear inner gear ring (103); radial rollers (7) are provided between the front inner gear ring (101) and the front movable gear frame (201) and between the rear inner gear ring (103) and the rear movable gear frame (203); and the radial rollers (7) are located on the inner side of the seal (5); An eccentric shaft assembly (3), the eccentric shaft assembly (3) comprising an eccentric shaft base (301), an eccentric shaft front bearing (302), an eccentric shaft rear bearing (303), a front shock wave device bearing (304), a rear shock wave device bearing (305), a front shock wave device (306) and a rear shock wave device (307), the eccentric shaft front bearing (302) and the eccentric shaft rear bearing (303) being arranged in a circumferential array between the two sides of the outer wall of the eccentric shaft base (301) and the front movable gear rack (201) and the rear movable gear rack (203), The eccentric shaft base (301) is movably arranged in the front movable gear frame (201) and the rear movable gear frame (203); a front shock wave generator (306) and a rear shock wave generator (307) are respectively arranged on both sides of the outer wall of the eccentric shaft base (301); the front shock wave generator bearing (304) and the rear shock wave generator bearing (305) are respectively arranged on two eccentric circles with the same eccentricity but angular positions different by 180 degrees on the eccentric shaft base (301) located on the inner sides of the front shock wave generator (306) and the rear shock wave generator (307); A movable tooth assembly (4), wherein the movable tooth assembly (4) is arranged between a front inner gear ring (101) and a front shock wave generator (306) and between a rear inner gear ring (103) and a rear shock wave generator (307), wherein the movable tooth assembly (4) comprises an outer core shaft (401), an inner core shaft (402), a movable tooth ring (403) and a needle roller (404), wherein both ends of the outer walls of the inner core shaft (402) and the outer core shaft (401) are provided with movable tooth rings (403), and between the movable tooth ring (403) and the inner core shaft (402) and the outer core shaft (401) are provided with needle rollers (404).

2. A two-layer roller movable tooth reducer with four-row cylindrical roller bearings according to claim 1, characterized in that: The outer circumferences of the front inner gear ring (101) and the rear inner gear ring (103) are respectively provided with positioning pin holes with an angular difference of 180 degrees, and positioning pins (105) are arranged in the positioning pin holes. The outer sides of the front inner gear ring (101) and the rear inner gear ring (103) are also tightened with connecting screws (104), and the inner ends of the connecting screws (104) and the positioning pins (105) are connected to the spacer sleeve (102).

3. A two-layer roller rolling movable tooth reducer with four-row cylindrical roller bearings according to claim 2, characterized in that: The outer circumferences of the front movable gear frame (201) and the rear movable gear frame (203) are tightened with two connecting screws (204), and the outer sides of the front movable gear frame (201) and the rear movable gear frame (203) are also provided with two positioning pins (205), and the inner ends of the two connecting screws (204) and the two positioning pins (205) are both connected to the middle movable gear frame (202).

4. A two-layer roller movable tooth reducer with four-row cylindrical roller bearings according to claim 3, characterized in that: The eccentric shaft assembly (3) also includes a front spacer (308) of the movable gear rack, a shock wave spacer (309) and a rear spacer (310) of the movable gear rack, wherein the front spacer (308) of the movable gear rack is arranged between the front movable gear rack (201) and the front shock wave (306), the shock wave spacer (309) is arranged between the front shock wave (306) and the rear shock wave (307), and the rear spacer (310) of the movable gear rack is arranged between the rear shock wave (307) and the rear movable gear rack (203).

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