JPS6049153A - Sun-and-planet gear device - Google Patents

Abstract

PURPOSE:To prevent shaft deflection by providing the second sun gear on the shaft tube of the first arm supporting the first planet gear and supporting the inner end section of an output shaft with this shaft tube in a planet gear device such as a reduction gear provided with two trains of planet gear mechanisms. CONSTITUTION:An annular wall 3 is protruded at the center of the inner periphery of a cylindrical outer box 1 fixed with end plates 4, 5 at the right and left opening ends, and a boss section formed in one body with the shaft tube 18 of the first arm 14 having the second sun gear 21 at the other end is rotatably supported to this annular wall 3 via a ball bearing 19. An input shaft 1 is rotatably supported to the left end plate 4 via a ball bearing 7, and two first planet gears 13 rotatably supported to a support shaft 15 planted on the first arm 14 are engaged with the first sun gear 11 at the inner end of the input shaft 1. In addition, two second planet gears 22 supported to the second arm 23 fixed to the inner end of an output shaft 26 via a support shaft 24 is engaged with the second sun gear 21, and the inner ends of the input and output shafts 1, 26 are supported in the shaft tube 18.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is a two-unit planetary gear machine, and its purpose is to provide a small planetary gear device that is free from shaft runout.

In conventional planetary gear systems, the input shaft and output shaft are supported only by bearings on the end plates, and because they are supported at one point, shaft runout is likely to occur. It is not possible to eliminate vibration, and the device becomes large.

The present invention provides a second sun gear in the shaft cylinder of the first arm that supports the first planetary gear, and loosely fits the inner ends of the input shaft and the output shaft into the shaft cylinder, so that both shafts are connected at two points. By adopting a supporting structure, they were able to obtain a large reduction ratio, and succeeded in developing a small planetary gear device with no shaft runout.

In the embodiment shown in the drawings, ■ is a horizontally cylindrical outer box with a mounting seat 2 on the bottom, and an annular wall 3 around the center of the inner peripheral surface.
protrude, cover the left and right opening surfaces with the end plates 4.5, and tighten several screws to the base of the annular wall 3 using bolts 6.6. Ball bearings 7 and 8 are fitted into the provided protrusions, respectively.

10 is an input shaft pushed through the left end plate 4, supported by a ball bearing 7, and inserted into the center of the outer box 1, and a tooth profile is cut on the curved surface near the inner end to form the first sun gear 11. and inner end 1
Leave a slightly longer bare part on 2. 13 is the first sun gear 11
The two first planetary gears mesh with the straight first arm 14.
It is supported via a roller bearing on a support shaft 15 that is erected in the outer case 1, and also meshes with a first internal gear 16 along the inner circumferential surface of the outer case 1. This first
The internal gear and the second internal gear (described later) are fixed to the outer box 1 by bolts 17 that pass through the base of the Km-shaped wall 3, and bolts 6.6 and 6. It passes through the second internal gear.

The first arm 14 is currently arranged on the left side (input shaft side) of the wall 3, and a long shaft cylinder 18 is connected to the boss to look into the opposite side (right side), and an annular shape is formed with the 18th shoulder. Ball bearing 1 between wall 3
9 is interposed to support the first arm 14 so that it does not wobble. The inner end 12 of the input shaft is inserted into this shaft cylinder 18 and supported by roller bearings 20, and the input shaft 10 is supported at two points, the end plate 4 and the shaft cylinder 18 of the first arm. The second thick gear 21 is formed by cutting a tooth profile on the outer peripheral surface of the gear.

Reference numeral 22 designates three second planetary gears that mesh with the second sun gear 21, and also mesh with a second internal gear portion on a support shaft installed on the trident-shaped second arm arm. Tighten bolt 1
7, it is fixed to the outer box 1. 26 is an output shaft inserted through the right end plate 5, supported by a ball bearing 8, inserted into the center of the outer case 1, passed through the boss of the second arm device, connected with the key 27, and then Cut the inner part to a small diameter in two stages, loosely fit the middle small diameter part into the shaft cylinder 18 of the first arm, and deeply fit the inner end hole into this shaft cylinder 18 to form the input shaft 10. approach the end face of the This output shaft 26 is the input shaft 1
0, and the inner end 29 is arranged on the same line as the roller bearing 30.
The output shaft is supported by the shaft cylinder 18 of the second arm, thereby supporting the output shafts at two points: the end plate 5 and the shaft cylinder 18 of the first arm.

One embodiment of the device of the present invention has the above configuration, and has an input shaft 1
0 rotates, the first sun gear 11 formed near the inner end of the same shaft rotates, and this sun gear and the fixed first internal gear 16 rotate.
The first planetary gear 13 meshing with the first planetary gear 13 revolves while rotating. As a result, the first arm 14 is decelerated and rotates, so the second sun gear 21 formed on the shaft cylinder 18 rotates, and the second sun gear 21 rotates.
A second planetary/star gear 6 that meshes with the sun gear and the second internal gear 25
revolves while rotating. From this example, the second arm leg rotates at a further reduced speed, and the output shaft 26 coupled to its boss
will rotate at a reduced speed.

Ko'1. In module 1), the number of teeth of the first sun gear 11 is 9, the number of teeth of the first planetary gear 13 is 38, the number of teeth of the first internal gear 16 is 85, and the number of teeth of the second thick gear 21 is 15.・Second
The number of teeth of the planetary gear 22 is 21, and the number of teeth of the second internal gear 25 is 5.
7 (module 1°5), 85 57 1 Reduction ratio: = (1 + -) X (1 + -) = -91550,1
3, and the speed is reduced to about IAo.

In this embodiment, the planetary gear mechanism has two sets, and a long shaft cylinder 18 is provided on the boss of the first arm 14 that supports the first planetary gear 13, and this shaft cylinder is attached to the inner peripheral surface of the outer box. The input shaft 1O is supported by an annular wall 3 protruding from the shaft, and the input shaft 10 is supported at two points, the end plate 4 and the shaft cylinder 18, by loosely fitting the inner end 12 of the input shaft into the shaft cylinder 18.
The inner end 29 of the output shaft is loosely fitted into the same shaft cylinder 1B, and the output shaft part is supported at two points, the end plate 5 and the shaft cylinder 18, and the input shaft and the output shaft are supported at two points. Therefore, there is no shaft runout at all, and since the bearings 7 and 8 installed on each end plate can be of a single row, the entire device can be downsized, and since the planetary gear mechanism has two sets, a large reduction ratio can be obtained. It will be done.

The above description describes one embodiment of the present invention, and the present invention is not limited to this embodiment, and the design can be changed within the spirit of the invention.

According to the present invention, the planetary gear machine is connected in two, and the input shaft and the output shaft are supported and held at two points: each end plate and the shaft cylinder of the first arm.1. This has the effect of making it possible to produce a planetary gear device that has a large reduction ratio, is small, and does not run out of its shaft.

[Brief explanation of the drawing]

The drawing is a sectional view showing an embodiment of the present invention. Note that 1 is an outer box, 3 is an annular wall, 4 and 5 are end plates, 10 is an input shaft, 11 is a first sun gear, 12 is an inner end thereof, 13 is a first free gear, 14 is a first arm, 16 is the first internal gear, 1
8 is the shaft cylinder of the first arm, 21 is the second sun gear, 22 is the second oscillating gear, holder is the second arm, 25 is the second internal gear, 26
is the output shaft, and 4 is its inner end.

Claims (1)

[Claims] An annular wall is provided at the center of the inner circumferential surface of the outer box, which is closed by covering end plates on both sides, and a first sun gear is formed at the end of the input shaft passing through one end plate. A first planetary gear that meshes with a first internal gear fixed to the box is supported on the first arm;
A long shaft cylinder is connected to the boss of the first arm, and its shoulder is supported by the annular wall of the outer case, and a second sun gear is formed on the outer peripheral surface of the shaft cylinder and fixed to this and the outer case. A second planetary gear meshing with the second internal gear is supported on the second arm, and an output shaft supported on the opposite end plate is coupled to the boss of the second arm, and the input shaft and output shaft are connected to each other. A planetary gear device characterized in that each inner end portion of the first arm is loosely fitted into the shaft cylinder of the first arm so that both shafts are supported at two points.