JPS62200056A - Synchromesh speed reducing device - Google Patents

Abstract

PURPOSE:To enhance the transmission efficiency by interposing rolling elements between an inner ring and an externally cogged gear, and thereby eliminating frictional loss due to slip to be generated between externally cogged gear and outer ring. CONSTITUTION:An externally cogged gear 4 is provided at its inner face with a groove of raceway 12 for running of rolling elements 7 of a bearing 3, to serve as an outer ring of the bearing 3. Thus the rolling elements 7 roll in the gap between this externally cogged gear 4 and inner ring 6. The inner ring 6 is pressure fitted on a rotor 2, and the rolling elements 7 are held by the inner ring 6 so that they are not movable in the axial direction. Accordingly the externally cogged gear 4 is consolidated with the inner ring 6 through rolling elements 7, that eliminates frictional loss due to slip otherwise generated between outer ring and externally cogged gear 4 to lead to enhancement of the power transmission efficiency.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention relates to an annular and flexible external gear wound around the outer periphery of a rotating body via a bearing, and an external gear that meshes with the external gear. The present invention relates to a harmonic gear reducer having an internal gear.

(Prior art) One or two internal gears are provided with force f, and an annular and external gear is flexibly deformed and meshed with the internal gear, and the rotation of the input shaft causes the internal and external gears to be connected to each other. The phase is shifted by the difference in the number of teeth, and this phase difference is transmitted to the output shaft to reduce the speed.
172), or a differential harmonic gear reducer in which the rotation of the input shaft shifts the phase by the difference in the number of teeth between the two internal gears, and this phase difference is transmitted to the output shaft (patent application published in 1982). No. 215142) is publicly known.

Next, the conventional differential type harmonic gear reducer is shown in Figures 3 and 4.
This will be explained based on the diagram.

FIG. 3 is an RK plane view of the harmonic gear reducer, and FIG. f54 is a cross-sectional view taken along line A-A in FIG. 3.

An elliptical rotary body 2 is fixed to the input shaft 1, and an annular and flexible external gear 4 is slidable on the outer periphery of the rotary body 2 via a bearing 3. The bearing 3 consists of an outer ring 5, an inner ring 6, and rolling elements 7, and is deformable.

The annular external gear 4 meshes with internal teeth $8.9 (described later) at two positions on the long axis side of the rotating body 2, and six external teeth that do not mesh with the internal gear 8.9 on the short axis side. Two internal gears 8.9 having different numbers of teeth are provided on the outer periphery of the tooth $4, the internal gear 8 is fixed to the casing 10, and the internal tooth 1#9 is connected to the output shaft 11. ing. Here, the number of teeth of one internal gear 8 is the same as that of the external gear 4, and the internal tooth RL8 and the internal tooth ]1
There is a difference in the number of teeth from No. 19.

Therefore, when the rotating body 2 rotates only once, the external gear 4 meshes with the internal gear 8.9, and since the internal gear 8 is fixed, the internal gear 9 is moved relative to the internal gear 9 by the difference in the number of teeth. The output shaft 11 rotates by the difference in the number of teeth. In this way, the rotation of the input shaft 1 is taken out as a decelerated rotation from the output @[111.

(Problem to be Solved by the Invention, α) However, the conventional differential harmonic gear reducer described above has the following problems.

Since the external gear 4 is wound and held around the outer circumference of the outer ring 5 only by a slight interference and a restoring force during deformation, it moves in the axial direction, and power transmission is not performed effectively. Energy loss occurs due to sliding friction at the contact portion between the external gear 4 and the outer ring 5, and a decrease in power transmission efficiency of the harmonic gear reducer is unavoidable.

Therefore, an object of the present invention is to eliminate sliding friction loss between an external gear and an outer ring, improve power transmission efficiency, and provide a harmonic gear reduction without axial movement of the external gear in a differential type harmonic gear reducer. The aim is to provide the opportunity.

(Means for Solving the Problems) In order to achieve the above object, the present invention has the following features.

That is, the present invention provides a bearing (
The transfer groove (12) of the transmission body (7) of 3) is provided, the external gear (4) also serves as the outer ring of the bearing (3), and the rotating body (
The rolling element (A) is characterized in that the rolling element (A) is transferred between the inner ring (6) fixed to the outer periphery of 2) or the outer periphery of the rotating body (2) and the external gear (4).

(Example) An example of the present invention is shown below in Figures 1 and 2 (A) (
The explanation will be based on the differential type harmonic gear reducer shown in b).

FIG. 1 is a longitudinal sectional view of a differential harmonic gear reducer showing this embodiment. FIG. 2(A) is a sectional view showing the inner surface of the external gear of the reducer shown in FIG. 1, and FIG. 2(B) is a front view thereof.

An elliptical rotating body 2 is fixed to the input shaft 1, and an annular and flexible external tooth 1 is attached to the outer periphery of the rotating body 2 via a bearing 3! L4 is wound. The external tooth $4 meshes with an internal gear 8.9 (described later) at two locations on the long axis side of the rotating body 2, and does not mesh with the internal gear 8.9 on the short axis side. A single transfer groove 12 for transferring the rolling elements 7 of the bearing 3 is provided on the inner surface of the external gear 4 in the circumferential direction so that the external gear 4 also serves as the outer ring of the bearing 3. A rolling element 7 is transferred between the rollers 6 and 6.

The inner ring 6 is press-fitted into the rotating body 2, and the rolling elements 7 are held in the inner ring 6 so as not to be able to move in the axial direction. Therefore, the external teeth $4 are integrated with the inner ring 6 via the rolling elements 7,
Axial movement of the external gear 4 is prevented. Furthermore, since the conventional outer ring is omitted, friction loss due to slippage between the outer ring and the external gear 4 is eliminated. Furthermore, compared to the conventional case in which the outer ring and the external teeth $4 are doubled, the resistance when deforming the external gear is reduced.

Two internal gears 8 and 9 are provided on the outer periphery of the external gear 4, the internal gear 8 is fixed to the casing 10, and the internal gear 9 is fixed to the casing 10.
is connected to the output shaft 11. Here, the number of teeth of the internal gear 8 is the same as the number of external teeth $4, and the internal gear 8 and the internal gear 9 have a difference in the number of teeth.

Therefore, when the rotating body 2 rotates only once, the external gear 4 meshes with the internal gear 8.9, and since the internal gear 8 is fixed, the internal gear 9 meshes with the internal gear 8. The output shaft 11 is relatively displaced by the difference in the number of teeth, and the output shaft 11 rotates by the phase of the difference in the number of teeth. In this way, the rotation of the input shaft 1 is extracted to the output shaft 11 as decelerated rotation.

It goes without saying that the present invention is not limited to the embodiments described above.

For example, the rotating body is not limited to an elliptical body, and may be any body that rotates with a non-contact portion with the internal gear, such as an eccentric body or a triangular body.

Furthermore, the rotating body may be formed integrally with the input shaft.

Furthermore, the rolling elements are not limited to balls, but may be rollers, cylinders, or other shapes.

Furthermore, the number of transfer grooves is not limited to - (1° Further, the inner ring can be omitted.

Furthermore, the number of teeth of the external gear does not need to be the same as the number of teeth of one internal tooth iL.

Furthermore, the types of harmonic gear reduction gears are not limited to the differential type, which has two internal gears that are out of phase by the difference in the number of teeth, thereby decelerating the gear, but also non-differential types, which extract the output transmission from the external gear. Needless to say, it's a good thing.

(Effect of the invention) According to the present invention, the following effects are achieved.

Since the outer ring of the bearing is omitted, there is no friction loss due to sliding between the outer ring and the external gear as in the conventional case, and power transmission loss is reduced.

Furthermore, compared to the conventional double outer ring and external gear, there is less resistance when deforming the external gear, so a harmonic gear reducer with small torque can be obtained, and at the same time, power transmission efficiency is improved. It will improve.

Further, since the external gear is integrated with the inner ring and the rotating body via the rolling elements, the external gear 4 is prevented from moving in the axial direction in the differential harmonic gear reducer. Therefore, the meshing centers of the external gear and the internal gear do not shift, and power transmission is performed satisfactorily.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional view of a differential type speed reducer according to an embodiment of the present invention. Figure i2 (A) is a sectional view showing the inner surface of the external gear in Figure 1, and Figure 2 (B) is a front view of the same external gear. FIG. 3 is a longitudinal sectional view of a conventional differential harmonic gear reducer. ptfJ4 Figure C, fj<3 Figure No A-Am't Uft surface view. Input shaft 2: Rotating body 3: Bearing 4: External gear L
6: Inner ring 7: Rolling element 8.9: Internal gear 11: Output shaft 12: Transfer groove Sub-agent Patent attorney Tsuji Sanbe Figure 1 Figure 2 (A) (B) Figure 3

Claims (1)

[Claims] A rotating body (2) fixed to an input shaft (1), and a rotating body (2) fixed to an input shaft (1).
2), an annular and flexible external gear (4) wound around the outer periphery of the gear via a bearing (3), and internal gears (8) and (9) that mesh with the external gear (4). and the external gear (4)
Alternatively, the output shaft (
11), and the rotation of the input shaft (1) is controlled by the output shaft (1).
In the harmonic gear reducer that takes out the decelerated rotation as described in 1), a transfer groove (12) for the rolling element (7) of the bearing (3) is provided on the inner surface of the external gear (4), and
) also serves as the outer ring of the bearing (3), and between the outer periphery of the rotating body (2) or the inner ring (6) fixed to the outer periphery of the rotating body (2) and the external gear (4). A harmonic gear reducer characterized in that the rolling elements (7) are configured to transfer.