JPS5936761Y2 - Case rotating differential reducer - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a case rotation type differential speed reducer that is small in size and has a simple structure.

A case rotation type differential reducer has external teeth formed on a pinion that rotates eccentrically, and internal teeth that mesh with the external teeth of the pinion are formed on the inner periphery of the case. , is rotating.

Such a case rotating type differential reducer is, for example, disclosed in Japanese Patent Publication No. 49-1.
It is known from the publication No. 332.

However, the reduction gear described in this publication has the following drawbacks.

In other words, the internal teeth formed on the case have an involute tooth profile, and the involute tooth profile has a high tooth depth. Coupled with the fact that the pinion needs to be eccentric beyond the tooth depth of the internal teeth so that the teeth can rotate beyond the internal teeth of the case, the amount of eccentricity of the pinion must be increased in the reducer described in the above publication. There is.

This has the disadvantage of increasing the outer diameter of the reducer.

Furthermore, in the reduction gear described in the above publication, the pair of bearings that rotatably support the case are not provided sufficiently close to the pinion, which increases the axial dimension of the reduction gear.

Therefore, the reduction gear described in the above-mentioned publication has the disadvantage that the external dimensions are too large.

In view of the above-mentioned points, it is an object of the present invention to provide a small-sized case rotation type differential speed reducer.

The present invention achieves this purpose by carving a plurality of circular arc grooves evenly spaced on the inner circumferential surface of the case and rotatably attaching pins to the circular grooves to form internal teeth. This is achieved by a case rotation type differential reducer in which the axial movement of the pin is not restricted by exposing the side surfaces of the outer ring of the bearing that rotatably supports the case at both axial ends of the pin.

In this invention, a pin gear is used for the internal teeth of the case, and the tooth depth is made sufficiently small, so that the eccentricity of the pinion having external teeth that meshes with the internal teeth can be reduced, and therefore the external gear of the reducer The diameter can be made smaller.

Furthermore, since the pair of bearings that support the case are provided very close to the internal teeth of the case, the spacing between the bearings can be made sufficiently small, and therefore the axial dimension of the speed reducer can be shortened.

Therefore, according to the present invention, the external dimensions of the case rotation type differential reducer can be reduced.

Furthermore, in this invention, since the pin of the pin gear is rotatable, the meshing efficiency between the internal teeth of the case and the external teeth of the pinion can be increased, and the load capacity of the reducer can be increased. A capacity reducer can be made smaller.

On the other hand, in the present invention, since the axial movement of the rotatable pin is directly regulated by the side surfaces of the bearing outer ring installed at both ends, there is no need for complicated measures to prevent the pin from being pulled out. There is no need to provide a snap ring or step to stop the bearing, and the structure is simplified.

An embodiment of the present invention will be described below with reference to the drawings.

First, referring to FIG. 1, a support block 10 is fixedly installed on a frame (not shown) of a crawler vehicle, and has a hydraulic motor 11 mounted therein.

The support block 10 includes a disc-shaped part 13 having a recess 12 into which the hydraulic motor 11 is inserted and fixed, and the disc-shaped part 13.
It includes a star-shaped column part 14 that projects from the top.

An annular flange portion 15 is formed around the disc-shaped portion 13, and a screw hole 16 is screwed into the flange portion 15 to complete the support block 1.
0 is screwed onto the frame of the crawler vehicle using bolts.

A center hole 18 is bored through the center of the star-shaped column 14, and the output rotating wheel 17 of the hydraulic motor 11 is inserted therein.

Furthermore, the end disk 19 forming a part of the support block 10 is attached to the pin 2.
0.20' and bolts 21, it is integrally connected to the column part 14 of the support block 10.

Mounting holes are equally spaced around the center hole, corresponding to the pillar portion 14 and the end disk 19, respectively, and roller bearings 22, 22' are mounted in the mounting holes.

Crank pin 23 between corresponding roller bearings 22, 22'
It is rotatably supported at both ends.

Here, the crank pin 23 has its rotation axis A.

Two crank parts 23 eccentrically positioned by a distance e with respect to D
a and 23b, and the pinion 1 is fitted into the crank portions 23a and 23b via bearings 24, respectively.

As shown in FIG. 2, the pinion 1 has two external teeth on its outer circumferential surface.
The crank pin 23 is connected to the crank pin 23 via the bearing 24 as described above.
is supported by

The pinion 1 further has a star-shaped groove 1a extending radially from its center, and the star-shaped groove 1a has a slightly larger dimension than the star-shaped column part 14 described above. The star-shaped column portion 14 is prevented from coming into contact with the wall surface of the star-shaped groove 1a during eccentric movement of the pinion 1.

Referring again to FIG. 1, the disc-shaped portion 1 of the support block 10
3 and the outer periphery of the end disk 19 are ball bearings 25.
26 to rotatably support the case 4.

A screw hole 4b is screwed into an annular flange portion 4a formed on the outer periphery of the case 4, and a drive sprocket or the like (not shown) of a crawler vehicle is bolted thereto, so that the drive sprocket is driven by the case 4. There is.

Referring to FIG. 2, on the inner periphery of the case 4, a large number of substantially semicircular arcuate grooves 6 are equally spaced in the circumferential direction.

Here, the number of circular arc grooves 6 is slightly larger than the external teeth formed on the outer periphery of the pinion 1, and the size thereof is slightly larger than the pin 5 inserted into the trial product 6, so that it has a small diameter cylindrical shape. The pin 5 is rotatable within the arcuate groove 6 and constitutes a hollow internal tooth 3.

The axial length of the arcuate groove 6 is made slightly longer than the length of the pin 5, as shown in FIG. 3, so as not to impede the rotation of the pin 5 within the arcuate groove 6.

On the inner periphery of the case 4, as shown in FIGS. 1 and 3, a bottom circle 8 of the internal tooth, that is, a circular arc groove, is continuous to both axial side surfaces 7, 7' of the circular arc groove 6 forming the internal tooth. Bearing holes 9, 9' of larger diameter are bored in the inner circumferential wall of the case before formation.

As shown in FIG.
5, 26 are assembled so that the side surfaces of the outer rings 25a, 26a abut against both side surfaces 7, 7' (FIG. 3) of the inner teeth, so that the side surfaces of the outer rings 25a, 26a face both ends of the pin 5 in the axial direction. It is possible to prevent the pin 5 from coming off in the axial direction without hindering its rotation within the arcuate groove 6.

In FIG. 1, a joint 27 is attached to the right end of the output rotation shaft 17.
The shaft portion of the first external gear 28 is spline-coupled via the spline.

Further, as described above, the second external gear 30 is spline-coupled to the right end of each of the three crank pins supported at both ends by the roller bearings 22 and 22'.

The second external gear 30 has a larger number of teeth than the first external gear 28, and the external gears 28, 30 mesh with each other.

The lid 29 is hermetically fastened to the case 4 from the outside of the external gears 28 and 30 with bolts 31, and a floating seal 32 is attached to the outside of the bearing 25 that rotatably supports the case 4.
to prevent lubricating oil from leaking inside the reducer.

The rotation of the output shaft 17 of the hydraulic motor 11 is transmitted from the first external gear 28 to the second external gear 30 meshing with the external gear 28 while being reduced in speed according to the ratio of the number of teeth between the two gears.

Due to the rotation of the second external gear 30, the roller bearing 22°22'
The crank pin 23, which is rotatably supported at both ends by the support block 10, rotates, and the crank parts 23a, 23 rotate.
b is rotated.

Due to this revolving movement, the crank portion 2
The pinion 1 engaged with 3a and 23b is eccentrically revolved.

This eccentric revolution movement of the pinion 1 causes engagement between the external teeth 2 formed on the outer periphery of the pinion 1 and the pin gear formed on the inner periphery of the case 4, and the case 4 is differentially decelerated rotated.

Thus, the drive sprocket attached to the case 4 drives the traveling system of the crawler vehicle.

Needless to say, the present invention is not limited to the above embodiments, and various changes can be made within the technical scope defined by the scope of the claims for utility model registration.
For example, the support block 10 may be formed integrally with the casing of the hydraulic motor 11.

[Brief explanation of the drawing]

1 is a sectional front view of an embodiment of the present invention, FIG. 2 is a sectional view taken along line AA in FIG. 1, and FIG. 3 is a partially enlarged view of FIG. 1. 1...Pinion, 2...External teeth, 3...
...Internal teeth, 4...Case, 5...
Pin, 6...Circular groove, 25.26...
Bearing, 25a, 26a...outer ring.

Claims (1)

[Scope of utility model registration request] In a case rotation type differential reducer in which external teeth are formed on a pinion that moves eccentrically and revolves, and internal teeth that mesh with the external teeth of the pinion are formed on the inner periphery of the case so that the case can be rotated,
A plurality of circular arc grooves are equally spaced on the inner peripheral surface of the case, and a pin is rotatably inserted into the circular groove to form the internal teeth,
A case rotation type difference characterized in that the side surface of an outer ring of a bearing rotatably supporting the case is exposed to both axial ends of the pin that controls the inner teeth, thereby restricting the axial movement of the pin. dynamic reduction gear.