JPS6023654A - Speed change gear - Google Patents

Abstract

PURPOSE:To achieve an automatic speed change gear of a small size and light weight capable of obtaining a greater variable ratio and also receiving the braking effect by arranging both carriers and internal gears in such a manner to stop rotation or rotate freely in a combination of 2 units of planetary gear decelerators and brake units. CONSTITUTION:The output shaft of a motor 7 is connected to an input shaft 8 which is coupled with sun gears 9a, 9b of 2 sets of planetary gear decelerators. Out of carriers 12a, 12b supporting planetary gears 10a, 10b of each decelerator, the carrier 12b is designed to receive the braking effect from an electromagnetic brake 16. Likewise, an internal gear 11b is designed to receive the brake from another electromagnetic brake 18 and an internal gear 11a is connected to an output shaft 19. Four types of combination are available on working conditions of the electromagnetic brakes 16, 18 for selecting either one of larger deceleration ratio, smaller deceleration ratio, free condition and condition under brake.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a transmission, and particularly to a transmission suitable for driving a robot.

[Background of the invention]

An example of a conventional general mobile robot wheel drive device is shown in FIG. A rotating shaft 3 of a wheel 2 rotatably supported by a frame 1 is rotated by a motor 5 via a speed reducer 4. A non-excitation type brake 6 is attached to the shaft end of the motor 5. This brake 6 is provided to prevent the speed reducer 4 and motor 5 from rotating out of control due to the torque of the wheels 2 due to the slope of the road surface when the power is cut off, and is essential for safety.

Since the conventional drive device shown in FIG. 1 has a constant reduction ratio, the reduction ratio must be determined from the output torque of the motor 5 and the maximum load torque applied to the wheels 2. Therefore, even when the load is small, it can only move at low speeds due to high decoupling. Therefore, in order to move at high speed when the load is small, it is necessary to replace the speed reducer 4 with a transmission that can select a reduction ratio depending on the size of the load. However, conventional transmissions have drawbacks such as complex mechanisms, being large and heavy, and the speed ratio not being large enough, making it difficult to install them in mobile robots with strict weight restrictions.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to provide an automatic transmission that is lightweight and compact, has a large gear ratio, and can also apply brakes.

[Summary of the invention]

The characteristics of the present invention are that two sets of planetary gear reducers with slightly different reduction ratios are arranged side by side, the two sun gears are connected by an input shaft, and the two carriers connecting the planet gears are integrated. In the reducer, one internal gear is arranged in a case and the other internal gear is connected to an output shaft, the carrier and the internal gear can each stop rotating or rotate freely. It is something.

[Embodiments of the invention]

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

FIG. 2 shows the configuration of an example of a transmission according to the present invention.

A motor 7 is provided on the right side of this figure.

This output shaft is connected to the input shaft 8 of the transmission.

Two sets of planetary gear reducers are incorporated inside the transmission. Input shaft 8 is coupled to sun gears 9a and 9b. Several planetary gears 10a, 10b are engaged around the sun gears 9a, 9b. An internal gear 113° 11b meshes with the outside thereof. A carrier 12a extends between the two sets of planetary gear reducers and supports planetary gears 10a and 10b. carrier 12
a is connected to the carrier 12b on the opposite side of the planetary gear 10b. Carrier 12b is connected to hollow shaft 13. The hollow shaft 13 is joined to the disc 14. The disk 14 is braked by a non-excitation operated electromagnetic brake 16 supported by a case 15. The internal gear 11b is coupled to the disc 17 and is supported by the case 15.
The brakes can now be applied. Internal gear lla is coupled to output shaft 19.

There are four combinations of operating states of the electromagnetic brakes 16 and 18. First, when the brake 16 is in the open state and the brake 18 is in the applied state, it operates as the aforementioned differential planetary gear reducer, and the reduction ratio increases. Conversely, if the brake 16 is in the applied state and the brake 1B is in the released state, the internal gear llb will not rotate freely and this planetary reducer will be ineffective. Since the carrier 12a is fixed to the brake 16, the transmission at this time consists of the sun gear 9a, the planetary gear 10a, and the internal gear l.
It acts as a single stage planetary gear reducer consisting of la. Therefore, the gear ratio is smaller than in the differential case.

When brakes 16 and 18 are both activated,
Since internal gear llb and carrier 12a are fixed, sun gear 9b cannot rotate.

Therefore, since the internal gear lla cannot rotate either, the output shaft 19 is fixed.

When the brakes 16 and 18 are in a released state, they are in an unrestricted state 9, and the input shaft 8 and output shaft 19 are in a free state in which they rotate independently.

FIG. 3 shows a specific embodiment of the present invention. Sun gears 9a and 9b are coupled to the input shaft 8.

Planetary gears 10a and 10b are engaged with the outer periphery. Internal gears 11a and llb are on the outside.
are interlocking. Internal gear lla is output shaft 1
It is connected to 9. Internal gear llb is disk 1
7 so that it can be operated by a brake 18. Planetary gears 10a and 10b are carrier 1
2a.

It is rotatably supported by 12b. carrier 12
, b are joined to the hollow shaft 13. The hollow shaft 13 is joined to a disk 14 so that it can be fixed by a brake 16, the brakes 16 and 18 being connected to the disk 14.17.
In order to apply the player's force to the shaft, the shaft is supported by thin spring plates 20 and 21 so as to be able to move somewhat in the axial direction, but is restrained by a pin 22 so as not to rotate.

This specific embodiment operates similarly to the configuration shown in FIG.

With this configuration, the configuration is simple and the gear ratio can be set sufficiently large.

〔Effect of the invention〕

As stated above, this research has made it possible to construct a lightweight and compact automatic transmission that can also apply brakes.
The effect is that the drive device can be configured compactly.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view showing the configuration of a conventional drive device, FIG. 2 is a diagram showing the principle configuration of the present invention, and FIG. 3 is a sectional view showing an example of a specific configuration of the present invention. 8... Input 11') B, 9a, 9b... Sun gear,
10a+10b...planetary gear, lla, llb
...Internal gear, 12a, 12b...Carrier, 13...Hollow till, 14.17...Disc plate,
15...Case, 16.18...Brake, 19.
...Output shaft, 20°Continued from page 1 0 Inventor Yoshiyuki Nakano 502 Sodatecho, Tsuchiura City, Hitachi, Ltd. Mechanical Research Laboratory

Claims (1)

[Claims] 1. Two sets of planetary gear reducers having slightly different gear ratios are arranged concentrically, and two sun gears of the planetary gear reducers are connected to an input shaft, and the planetary gear reducer In a differential planetary gear reducer in which the two carriers of the V4iJ gear reduction transmission are connected, one of the two internal gears of the V4iJ gear reduction transmission is arranged in the case, and the other is connected to the output shaft, the carrier is connected to the first A brake means allows the case to stop or freely rotate as desired, and a second brake means allows the internal gear disposed in the case to stop or freely rotate as desired with respect to the case. A transmission characterized by: 2. The transmission according to claim 1, wherein the brake means is an electromagnetic brake. 3. The transmission according to claim 2, wherein the electromagnetic brake is a non-excitation operated electromagnetic brake.