JPS6364661B2 - - Google Patents

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]

For example, as a conventional mobile robot,
There is one described in Publication No. 194171. An example of this type of general 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 reduction gear 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 reducer 4 and motor 5 from rotating in the opposite direction due to the torque of the wheels 2 due to the inclination 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 deceleration. For this reason, 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 allows the speed reduction ratio to be selected depending on the size of the load. However, conventional transmissions have complex mechanisms, are large and heavy, and have drawbacks such as the inability to maintain a sufficiently large gear ratio, which poses many problems when installed 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. A reduction gear in which one internal gear is placed in a case and the other internal gear is connected to an output shaft, in which the carrier and the internal gear can each stop rotating or rotate freely. It is.

[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 built into the transmission. The input shaft 8 has sun gears 9a and 9b.
is combined with Several planetary gears 10a, 10b mesh around the sun gears 9a, 9b. Internal gear 1 is on the outside.
1a and 11b are engaged. A carrier 12a is located between the two sets of planetary gear reducers and supports planetary gears 10a, 10b. Carrier 1
2a is connected to the carrier 12b on the opposite side of the planetary gear 10b. The carrier 12b is connected to the hollow shaft 13. The hollow shaft 13 is a disk 14
It is joined to. The disc 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.
8 allows the brakes to be applied. Internal gear 11a 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, when the brake 16 is in the brake operating state,
When the brake 18 is in the brake release state, the internal gear 11b rotates freely and this planetary reduction gear becomes ineffective. Since the carrier 12a is fixed by the brake 16, the transmission at this time functions as a single-stage planetary gear reduction gear composed of a sun gear 9a, a planetary gear 10a, and an internal gear 11a. Therefore, the gear ratio is smaller than in the differential case.

When the brakes 16 and 18 are both activated, the internal gear 11b and the carrier 12
Since a is fixed, the king gear 9b cannot rotate. Therefore, since the internal gear 11a 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, 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 gear 1 is on the outside.
1a and 11b are engaged. Internal gear 11a is coupled to output shaft 19. Internal gear 11b is joined to disc 17 and can be fixed by brake 18. Planetary gears 10a, 10b are carriers 12a, 1
It is rotatably supported by 2b. The carrier 12b is joined to the hollow shaft 13. Hollow shaft 1
3 is joined to a disc 14 and can be fixed by a brake 16. The brakes 16 and 18 are supported by thin spring plates 20 and 21 in order to apply braking force to the discs 14 and 17, and are allowed to move somewhat in the axial direction, but are restrained by pins 22 so as not to rotate. ing.

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

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

[Effects of the Invention] As described above, according to the present invention, a lightweight and compact automatic transmission can be configured and a brake can also be applied, so there is an effect that the drive device can be configured compactly.

[Brief explanation of drawings]

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 shaft, 9a, 9b...Sun gear, 10
a, 10b...planetary gear, 11a, 11b
...Internal gear, 12a, 12b...Carrier, 13...Hollow shaft, 14, 17...Disc, 1
5... Case, 16, 18... Brake, 19...
...Output shaft, 20, 21...Spring plate, 22...Pin.

Claims (1)

[Scope of Claims] 1. Two sets of planetary gear reducers having slightly different gear ratios are arranged concentrically, two sun gears of the planetary gear reducers are coupled to an input shaft, and two sets of planetary gear reducers of the planetary gear reducers are connected to an input shaft. In a differential planetary gear reducer in which two internal gears of the planetary gear reducer are coupled, one of the two internal gears of the planetary gear reducer is disposed in a case, and the other is coupled to an output shaft, the carrier is driven by a first braking means. The case can be arbitrarily stopped or rotated freely, and the internal gear disposed in the case can be stopped or rotated freely with respect to the case by a second brake means. A transmission featuring: 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.