CN211259499U

CN211259499U - Small tooth difference four-gear pair meshing speed reducer

Info

Publication number: CN211259499U
Application number: CN201922119991.6U
Authority: CN
Inventors: 黄子帅; 胡仁惠
Original assignee: Individual
Current assignee: Individual
Priority date: 2019-11-28
Filing date: 2019-11-28
Publication date: 2020-08-14
Anticipated expiration: 2029-11-28

Abstract

The utility model discloses a little poor four gear pair meshing reduction gear of tooth, two duplicate gears that are arranged oppositely and distribute are assembled in the middle of the cross roller bearing of two opposite installations, all dispose one rather than the fixed gear of meshing between each duplicate gear and the cross roller bearing of corresponding side, the output gear cover is established in the periphery of two duplicate gears, the input crankshaft is then installed in the middle part of two duplicate gears, the holistic part is small in quantity, and do not contain the deformation piece, the inside need not to provide the redundant space that the flexible part deformation cushioned, simple structure is compact, small; moreover, its duplicate gear meshes with fixed gear, output gear mutually simultaneously, has formed the location, has greatly improved positioning accuracy, and eliminates the influence of backlash to a certain extent, has improved the precision of repeated location, and this utility model is used for transmission technical field.

Description

Small tooth difference four-gear pair meshing speed reducer

Technical Field

The utility model relates to a transmission technical field especially relates to a poor four gear pair meshing reduction gears of few tooth.

Background

In the industry fields of aerospace, industrial robots, processing equipment and the like, three generally used reducers are respectively a harmonic reducer, an RV reducer and a planet wheel reducer, but the harmonic reducer and the RV reducer are overlarge in size and weight, low in precision, small in reduction ratio range, large in processing difficulty and high in manufacturing cost; the planetary reducer has the problem of low precision, generally 1-3 angular divisions, and the input shaft has a large eccentric amount, so that in the operation process, the input shaft needs to bear eccentric torque, so that the highest rotating speed is very low.

Furthermore, the three types of speed reducers described above have a common drawback: there is no self-locking. If the load torque received by the output end is larger than the driving torque, the output end of the output end can be carried away by the load, if the output end is installed on a robot or an aerospace vehicle and other equipment, serious safety accidents can be caused, the current solution is to add a brake mechanism at the input end of a speed reducer, but the weight and the volume of the whole component module can be increased, and the reliability cannot be guaranteed.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to solve one of the technical problem that exists among the prior art at least, provide a little poor four-gear pair meshing reduction gear of tooth small, compact structure and precision height.

The utility model adopts the technical proposal that:

a small tooth difference four-gear pair meshing speed reducer comprises:

a pair of crossed roller bearings, the two crossed roller bearings being installed oppositely;

the double gears are oppositely assembled between the two crossed roller bearings, each double gear comprises a small gear ring and a large gear ring which are coaxially arranged, and the large gear ring is an outer gear ring;

the output gear is sleeved on the peripheries of the two duplicate gears, and an inner gear ring of the output gear is meshed with a large gear ring of the two duplicate gears;

the input crankshaft is arranged in the middle of the two duplicate gears, and at least one bearing is respectively arranged between the input crankshaft and the two duplicate gears as well as between the input crankshaft and the two crossed roller bearings;

and a fixed gear is respectively arranged between each duplicate gear and the crossed roller bearing on the corresponding side, and each fixed gear is respectively engaged and assembled with the small gear ring on the corresponding side.

Further conduct the utility model discloses technical scheme's improvement, cross roller bearing includes mounting flange, cover and establishes output flange outside mounting flange, with the outer raceway piece that output flange fastens mutually, mounting flange divide into inner circle portion and outer lane portion, form the raceway between the surface of outer raceway piece, output flange and outer lane portion, be equipped with the roller in the raceway.

Further conduct the utility model discloses technical scheme's improvement, the length of inner circle portion is greater than the length of outer circle portion, the middle part of inner circle portion and outer circle portion forms the slot hole, little ring gear is located the slot hole.

Further conduct the utility model discloses technical scheme's improvement, little ring gear is the ring gear, fixed gear adopts outer ring gear, the inner wall and the interior laminating of circle portion of fixed gear are fixed.

Further conduct the utility model discloses technical scheme's improvement, little ring gear is outer ring gear, fixed gear adopts the ring gear, the outer wall and the laminating of outer lane portion of fixed gear are fixed.

Further conduct the utility model discloses technical scheme's improvement, the surface of outer lane portion is equipped with the one-level step, the bearing card is put between one-level step and input crankshaft.

Further conduct the utility model discloses technical scheme's improvement, two flange, two through screw fixed connection respectively between output flange and the output gear.

Further conduct the utility model discloses technical scheme's improvement, the input crankshaft divide into two eccentric circle sections, two the eccentric circle section includes an embedded bearing and two overcoat bearings that set up side by side respectively.

Further conduct the utility model discloses technical scheme's improvement, two the phase difference of eccentric circle section is 180, two the eccentricity size of eccentric circle section equals.

Further conduct the utility model discloses technical scheme's improvement, the bearing is deep groove ball bearing or angular contact ball bearing.

The utility model has the advantages that: according to the four-gear-pair meshing speed reducer with the small tooth difference, two duplicate gears which are distributed in an opposite mode are assembled between two opposite crossed roller bearings, a fixed gear meshed with each duplicate gear is configured between each duplicate gear and the corresponding crossed roller bearing, an output gear is sleeved on the periphery of the two duplicate gears, an input crankshaft is installed in the middle of the two duplicate gears, the number of integral components is small, a deformation piece is not contained, a redundant space for deformation buffering of a flexible component is not required to be provided inside the input crankshaft, the structure is simple and compact, and the size is small; moreover, the duplicate gear is meshed with the fixed gear and the output gear simultaneously, so that over-positioning is formed, the positioning precision is greatly improved, the influence of backlash is eliminated to a certain extent, and the precision of repeated positioning is improved.

Drawings

The present invention will be further explained with reference to the accompanying drawings:

fig. 1 is an elevation view of an assembly structure according to an embodiment of the present invention;

fig. 2 is a cross-sectional view of an assembly structure according to an embodiment of the present invention;

FIG. 3 is an exploded view of an embodiment of the present invention;

fig. 4 is a cross-sectional view of an assembly structure of another embodiment of the present invention;

fig. 5 is an exploded view of another embodiment of the present invention.

Detailed Description

This section will describe in detail the embodiments of the present invention, preferred embodiments of the present invention are shown in the attached drawings, which are used to supplement the description of the text part of the specification with figures, so that one can intuitively and vividly understand each technical feature and the whole technical solution of the present invention, but they cannot be understood as the limitation of the protection scope of the present invention.

In the description of the present invention, it should be understood that the orientation or positional relationship indicated with respect to the orientation description, such as up, down, front, rear, left, right, etc., is based on the orientation or positional relationship shown in the drawings, and is only for convenience of description and simplification of description, and does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention.

In the description of the present invention, a plurality of means are one or more, a plurality of means are two or more, and the terms greater than, less than, exceeding, etc. are understood as not including the number, and the terms greater than, less than, within, etc. are understood as including the number. If the first and second are described for the purpose of distinguishing technical features, they are not to be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated or implicitly indicating the precedence of the technical features indicated.

In the description of the present invention, unless there is an explicit limitation, the words such as setting, installation, connection, etc. should be understood in a broad sense, and those skilled in the art can reasonably determine the specific meanings of the above words in combination with the specific contents of the technical solution.

Referring to fig. 1 to 3, in order to implement the present invention, a meshing reducer with four gear pairs with small tooth difference is described, which includes a pair of crossed roller bearings 1, a pair of duplicate gears 2a, an output gear 3 and an input crankshaft 4.

Specifically, two crossed roller bearings 1 are installed oppositely, two duplicate gears 2a are assembled oppositely in the middle of the two crossed roller bearings 1, each duplicate gear 2a comprises a small gear ring 21a and a large gear ring which are coaxially arranged, the number of teeth of the large gear ring is different from that of the small gear ring 21a, the tooth profile is the modified involute tooth profile or the modified cycloid tooth profile, further, the large gear ring is an outer gear ring, and the small gear ring 21a is an inner gear ring; furthermore, the output gear 3 is sleeved on the periphery of the two duplicate gears 2a, and the inner gear ring thereof is engaged with the large gear rings of the two duplicate gears 2 a. The input crankshaft 4 is installed in the middle of the two duplicate gears 2a, two deep groove ball bearings 5 are respectively arranged between the input crankshaft 4 and the two duplicate gears 2a, one deep groove ball bearing 5 is respectively installed between the input crankshaft 4 and the two duplicate gears 2a, and furthermore, each deep groove ball bearing 5 can be replaced by an angular contact ball bearing.

Further, an external ring gear is disposed between each double gear 2a and the corresponding side crossed roller bearing 1 as a fixed gear 6a, and each fixed gear 6a is engaged with the corresponding side small ring gear 21 a.

According to the meshing speed reducer with the small tooth difference and the four gear pairs, two duplicate gears 2a which are distributed in an opposite mode are assembled between two crossed roller bearings 1 which are installed in an opposite mode, a fixed gear 6a which is meshed with each duplicate gear is configured between each duplicate gear 2a and the crossed roller bearing 1 on the corresponding side, an output gear 3 is sleeved on the periphery of the two duplicate gears 2a, an input crankshaft 4 is installed in the middle of the two duplicate gears 2a, the whole speed reducer is small in number of components and does not contain a deformation part, a redundant space for deformation buffering of a flexible part is not needed to be provided in the speed reducer, the structure is simple and compact, and the size is small; moreover, the duplicate gear 2a is meshed with the fixed gear 6a and the output gear 3 simultaneously, so that over-positioning is formed, the positioning precision is greatly improved, the influence of backlash is eliminated to a certain extent, and the precision of repeated positioning is improved.

Specifically, in the present embodiment, the crossed roller bearing 1 includes a fixed flange 11, an output flange 12 sleeved outside the fixed flange 11, and an outer raceway block 13 fastened to the output flange 12, where the fixed flange 11 is divided into an inner ring portion and an outer ring portion, a raceway is formed between the outer raceway block 13, the output flange 12, and an outer surface of the outer ring portion, and rollers 14 are disposed in the raceway. It should be noted that, when the small tooth difference four-gear pair mesh speed reducer is manufactured into a miniature version, which is not beneficial to the installation of the roller, the roller can be replaced by using the ball. Further, the length of the inner ring portion is larger than that of the outer ring portion, a long hole is formed in the middle of the inner ring portion and the outer ring portion, the small gear ring 21a of the duplicate gear 2a is placed in the long hole, the inner wall of the fixed gear 6a is fixedly attached to the inner ring portion, more specifically, the fixed gear 6a and the inner ring portion can be fixed in a press fitting mode, a hot fitting mode or other modes, and the fixing mode can be selected according to actual operation conditions.

Furthermore, two fixing flanges 11, two output flanges 12 and the output gear 3 are respectively fixedly connected through screws 7, in order to improve the aesthetic degree of the whole structure in the embodiment, the screws 7 connecting the output flanges 12 and the output gear 3 are divided into six groups, each group is 3, and the screws 7 of each group are distributed around the periphery of the output flange 12 at equal angles.

In the present embodiment, the input crankshaft 4 is preferably divided into two eccentric circular segments, the phase difference between the two eccentric circular segments is 180 °, and the eccentricity of the two eccentric circular segments is equal. The phase difference of the eccentric circle sections is 180 degrees, namely the eccentric torque is 0, so that the duplicate gear 2a can not generate eccentric force in the rotating process, and can rotate quickly, and the linear velocity of the tail end can reach more than 300 m/s. Specifically, each eccentric circle segment is composed of an embedded bearing 41 and two outer sleeve bearings 42 arranged in parallel.

Specifically, assuming that the number of teeth of the output gear 3 is z1, the number of teeth of the external gear of the duplicate gear 2a is z2, the number of teeth of the internal gear of the duplicate gear 2a is z3, and the number of teeth of the ring gear of the fixed gear 6a is z4, the operation modes of the small tooth difference four-gear pair meshing speed reducer of the present embodiment can be divided into the following two types:

the first method comprises the following steps: the fixed end is a fixed flange 11; the input end is an input crankshaft 4; the output end is an output flange 12.

The fixed flange 11 is fixed and then the input crankshaft 4 is rotated; the eccentric circle section of the input crankshaft 4 drives the dual gear 2a to do eccentric motion, so that the dual gear 2a drives the output flange 12 to do deceleration rotation motion; meanwhile, the duplicate gear 2a is restrained by the fixed gear 6a and performs reduced-speed rotary motion; since the two decelerated rotary motions are in the same direction, the motion of the final output flange 12 is a superposition of the two decelerated rotary motions, and the final motion direction is the same as the input crankshaft rotation direction.

Assuming that the reduction ratio of the output end to the input end is i1, the calculation formula is:

and the second method comprises the following steps: fixing end: an output flange 12; input end: an input crankshaft 4; output end: the flange 11 is fixed.

The output flange 12 is fixed and then the input crankshaft 4 is rotated; the eccentric circle of the input crankshaft 4 drives the dual gear 2a to do eccentric motion, so that the dual gear 2a drives the fixed flange 11 to do deceleration rotation motion; meanwhile, the duplicate gear 2a is restrained by the output gear 3 and performs reduced rotation movement; since the two decelerated rotary motions are in the same direction, the final motion of the fixed flange 11 is a superposition of the two decelerated rotary motions, the final motion direction being opposite to the input crankshaft rotation direction.

If the reduction ratio of the fixed end to the input end is i2, the calculation formula is:

referring to fig. 4 and 5, the small teeth difference four-gear pair mesh speed reducer in this embodiment is another embodiment of the present invention, and includes the same components as those in the previous embodiment, and the assembly relationship is also the same. The difference from the previous embodiment is that in the present embodiment, the small gear ring 21b of the dual gear 2b is an external gear ring, the correspondingly engaged fixed gear 6b is an internal gear ring, and the outer wall of the fixed gear 6b is attached and fixed to the outer ring portion of the fixed flange 11.

In order to limit and fix the deep groove ball bearing provided between the cross roller bearing 1 and the output crankshaft, the outer surface of the outer ring portion of the fixing flange 11 of the present embodiment is provided with a first step, and the deep groove ball bearing is engaged between the first step and the input crankshaft 4.

In this embodiment, if the number of teeth of the output gear 3 is z1, the number of teeth of the external gear of the duplicate gear 2b is z2, the number of teeth of the internal gear of the duplicate gear 2b is z3, and the number of teeth of the ring gear of the fixed gear 6b is z4, the operation modes thereof can be divided into the following two types:

the first method comprises the following steps: fixing end: a fixed flange 11; input end: an input crankshaft 4; output end: an output flange 12.

The fixed flange 11 is fixed and then the input crankshaft 4 is rotated; the eccentric circle of the input crankshaft 4 drives the dual gear 2b to do eccentric motion, so that the dual gear 2b drives the output flange 12 to do deceleration rotation motion; meanwhile, the duplicate gear 2b is restrained by the fixed gear 6b and performs reduced-speed rotary motion; since the two decelerated rotary motions are in opposite directions, the motion of the final output flange 12 is a superposition of the two decelerated rotary motions, the final motion direction being opposite to the input crankshaft rotation direction.

The output flange 12 is fixed and then the input crankshaft 4 is rotated; the eccentric circle of the input crankshaft 4 drives the duplicate gear 2b to do eccentric motion

The duplicate gear 2b is restrained by the output gear 3 and performs reduced rotation movement; since the two decelerated rotary motions are in opposite directions, the final motion of the fixed flange 11 is a superposition of the two decelerated rotary motions, and the final motion direction is the same as the input crankshaft rotation direction.

the number of teeth of the small-module gear is generally not more than 400, and in this embodiment, the more commonly used values are taken, where the tooth number z1 of the output gear 3 is 321, the outer gear tooth number z2 of the duplicate gear 2b is 320, the inner gear tooth number z3 of the duplicate gear 2b is 319, and the ring gear tooth number z4 of the fixed gear 6b is 320, and the above formula is substituted to obtain i 1-102399, and i2 is 102400, so that it can be seen that the small-gear-difference four-gear-pair meshing speed reducer in this embodiment adopts a single-stage double-gear-pair meshing transmission method and takes the difference between two motions, so that the single stage can achieve a large reduction ratio of 100000 or more.

The small tooth difference four-gear pair meshing speed reducer of the two embodiments has the characteristic of mechanical self-locking, the maximum allowable self-locking torque is set as T, the destructive torque of a single pair of meshing gear teeth of an internal gear pair formed by a fixed gear and a small ring gear in a duplicate gear in the two embodiments is set as T0, the meshing rate of the fixed gear ring gear is set as eta 4, and the calculation formula for obtaining the maximum allowable self-locking torque is as follows: t2 · T0 · z4 · η 4; when the load torque received by the output end exceeds the driving torque but does not reach the maximum allowable self-locking torque T, the load torque can not make the eccentric circle of the input crankshaft 4 rotate to realize self-locking, so that the self-locking mechanism is safer and more reliable.

In addition, in the small tooth difference four-gear pair meshing speed reducer of the two embodiments, the number of meshing teeth is large, so that the allowable torque is large, the load capacity is improved, the unit volume load torque is larger than that of the harmonic speed reducer and the RV speed reducer, and the volume and the weight are far smaller than those of the harmonic speed reducer and the RV speed reducer under the same rated load. Meanwhile, the two bearings adopt the design of the opposite crossed roller bearing 1, the output flanges 12 are mutually fastened, and the input flanges are mutually fastened, so that the bearing device can bear larger torque and bending moment.

Naturally, the invention is not limited to the above-described embodiments, and those skilled in the art can make equivalent modifications or substitutions without departing from the spirit of the invention, and such equivalent modifications or substitutions are included in the scope of the claims of the present application.

Claims

1. A small tooth difference four-gear pair meshing speed reducer is characterized by comprising:

2. The small tooth difference four-gear pair mesh speed reducer according to claim 1, characterized in that: the crossed roller bearing comprises a fixed flange, an output flange and an outer raceway block, wherein the output flange is arranged outside the fixed flange, the outer raceway block is fastened with the output flange, the fixed flange is divided into an inner ring portion and an outer ring portion, a raceway is formed between the outer surfaces of the outer raceway block, the output flange and the outer ring portion, and rollers are arranged in the raceway.

3. The small tooth difference four-gear pair mesh speed reducer according to claim 2, characterized in that: the length of the inner ring portion is larger than that of the outer ring portion, a long hole is formed in the middle of the inner ring portion and the outer ring portion, and the small gear ring is located in the long hole.

4. The small tooth difference four-gear pair mesh speed reducer according to claim 3, characterized in that: the small gear ring is an inner gear ring, the fixed gear adopts an outer gear ring, and the inner wall of the fixed gear is fixedly attached to the inner ring part.

5. The small tooth difference four-gear pair mesh speed reducer according to claim 3, characterized in that: the small gear ring is an outer gear ring, the fixed gear adopts an inner gear ring, and the outer wall of the fixed gear is fixedly attached to the outer ring part.

6. The small tooth difference four-gear pair mesh speed reducer according to claim 5, characterized in that: the outer surface of the outer ring part is provided with a first-stage step, and the bearing is clamped between the first-stage step and the input crankshaft.

7. The small tooth difference four-gear pair mesh speed reducer according to claim 2, characterized in that: the two fixing flanges, the two output flanges and the output gear are fixedly connected through screws respectively.

8. The small tooth difference four-gear pair mesh speed reducer according to claim 1, characterized in that: the input crankshaft is divided into two eccentric circle sections, and the two eccentric circle sections respectively comprise an embedded bearing and two outer sleeve bearings arranged in parallel.

9. The small tooth difference four-gear pair mesh speed reducer according to claim 8, characterized in that: the phase difference of the two eccentric circle sections is 180 degrees, and the eccentricity of the two eccentric circle sections is equal in size.

10. The small tooth difference four-gear pair mesh speed reducer according to claim 1, characterized in that: the bearing is a deep groove ball bearing or an angular contact ball bearing.