JPS6023633A - Clutch device of planetary gear mechanism - Google Patents

Abstract

PURPOSE:To prevent oil leakage and avoid concentration of stress due to welding in a clutch device including a planetary gear mechanism, by permitting an internal threaded gear to be fixed by means of a pressure tube. CONSTITUTION:An internal threaded gear 8 is loosely incorporated in a casing 1, and is formed with a radially extending rib 8a at an outer circumference thereof. The rib 8a faces to a friction plate 9, and a ring-like tube 10 is provieed on a back side of the friction plate 9. The friction plate 9 is meshed with a spline 11 formed on an inner surface of the casing 1, and is allowed to be axially slided. The ring-like tube 10 is fixed through a supply pipe 12 formed in the casing 1, and is adapted to be supplied with or discharge a hydraulic oil through the supply pipe 12. Accordingly, the internal threaded gear 8 may be strongly retained between the friction plate 9 and the casing 1 by supplying the hydraulic oil.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a clutch device comprising a planetary gear mechanism.

In a hydraulic clutch device in which a clutch friction plate is pressed and fixed by a piston of a hydraulic cylinder, if the piston is formed into a ring shape, it is possible to apply a large non-electrically large force to a narrow ring-shaped area with a compact structure. You will be able to apply pressure. However, this configuration of cylinder and piston not only has a complicated mechanism, but also has problems such as oil leakage and reduced work efficiency unless precision machining is performed.

In order to solve this problem, the present inventor previously proposed using a ring-shaped bellows as a fluid pressurizing means instead of a hydraulic cylinder. However, since this bellows is made by welding multiple bellows-shaped thin plates along the circumferential direction,
In addition to being troublesome to manufacture, there is another problem in that stress buildup is induced in the welded part, making it more likely to burst.

In view of the above-mentioned problems, it is an object of the present invention to avoid a drop in work efficiency due to oil leakage, unlike in hydraulic cylinders, and to have no welded parts on the cross section unlike bellows, which is easy to work with and reduces stress. It is an object of the present invention to provide a clutch device comprising a planetary gear mechanism that does not cause rupture due to concentration and can be manufactured at low cost.

A clutch device according to the present invention that achieves the above object has a planetary gear mechanism interposed between an input shaft and an output shaft, puts an internal gear of this planetary gear mechanism in an idle state, and provides an outer periphery of the internal gear. A ring-shaped tube having a seamless cross section is opposed to the protruding rim portion via a friction plate, and the ring-shaped tube is applied with its tube supporting surface side and the side facing the friction plate in a restrained state. It is possible to supply pressure fluid,
It is characterized in that the tube is expanded by supplying pressurized fluid to press the rim portion, thereby making it possible to fix and stationary the internal gear.

Hereinafter, the present invention will be explained with reference to embodiments shown in the drawings.

In FIG. 1, l is a casing, and an input shaft 2 is provided on one side of the casing, and an output shaft 3 is provided on the other side, and a planetary gear mechanism 4 is interposed between these two shafts 2 and 3. are doing. A sun gear 5 is fixed to the end of the input shaft 2, and planet gears 6 are arranged around the sun gear 5 so as to mesh therewith. This planetary gear 6 is rotatably supported by a shaft 7a of a carrier 7 fixed to the output shaft 2. Further, a ring-shaped internal gear 8 meshes with the outer periphery of the planetary gear 6.

The internal gear 8 is in a floating state and is not fixed to the casing I, and has a rib portion 8a extending in the radial direction on its outer periphery. A friction plate 9 faces this rib portion 8a, and a ring-shaped tube lO is provided on the back side of the friction plate 9.
is provided. The friction plate 9 meshes with a spline 11 formed on the inner surface of the casing 1 so as to be able to slide in the axial direction. Further, the ring-shaped tube IO is fixed via a supply pipe 12 installed inside the casing l, and hydraulic oil is supplied and discharged via this supply pipe 12.

As shown enlarged in FIGS. 2A and 2B, the ring-shaped tube 10 is a thin-walled tube made of #I and has no seam in its cross section, and is entirely ring-shaped. When hydraulic oil is supplied to this duplex 10, as shown in an enlarged view in FIG. Expansion is performed as shown, and the friction plate 9 is pressed toward the rib portion 8a of the internal gear 8. Due to this pressing, the internal gear 8 is firmly clamped and fixed between the friction plate 9 and the casing 1, so that the power of the input shaft 2 is transmitted to the output shaft 3 via the planetary gear mechanism 4. On the other hand, when the supply of hydraulic oil is released, the tube 10 returns to the position indicated by the solid line in FIG. state. Therefore, power transmission from the input shaft 2 to the output shaft 3 is interrupted.

It is sufficient that the distance by which the friction plate 9 is moved by the expansion of the tube 10 is about 1 to 21 degrees.

The cross-sectional shape of the ring-shaped tube 10 to enable such an amount of expansion needs to be seamless so as not to rupture due to stress concentration due to the internal pressure of the fluid. Further, it is desirable that the cross-sectional shape is long in the plane direction including the ring shape and short in the direction orthogonal to the plane. In addition to the shapes shown in Figures 1 and 2 above, there is also a tube 1 with a multilayer structure as shown in Figure 4.
0, or the tube 10 may have a shape in which both ends of the cross section are bulged as shown in FIG. In the former case, the strength against fluid internal pressure is increased and the flexibility is improved, so the expansion stroke can be made relatively large, and in the latter case, the expansion stroke can be similarly made large due to the bulging portions at both ends.

The material of the duplex 10 needs to be able to withstand the internal pressure of the fluid and have elastic recovery so that it can contract back to its original shape after expansion, so it is most preferably made of steel, but it must not have the strength to withstand the internal fluid pressure. If available, fiber reinforced resin (F
RP) etc. can also be used.

The ring-shaped tube 10 is, for example, as shown in FIGS. 6A and 6B.
It can be easily manufactured by step C.

That is, first, as shown in FIG. 6, a thin steel tube 10 is cut to a predetermined length and bent into a circular shape in the direction of the arrow.
It is formed into a ring shape as shown in FIG. 6B, and finally both ends 10e+10e are welded. Next, this ring-shaped sleeved tube 10 is sandwiched between press plates 20 and 20 as shown in FIG. '', the ring-shaped tube 10 can be obtained. However, if a tube with an oval cross section is used from the beginning, the final pressing step is not necessary.

As described above, in the clutch device using the planetary gear mechanism of the present invention, the fluid pressurizing means is composed of the ring-shaped tube 10 that expands with only both end surfaces restrained.
Unlike a hydraulic cylinder composed of a cylinder and a piston, there is no reduction in work efficiency due to oil leakage, and there is no need for expensive precision machining to prevent oil leakage. Further, since the ring-shaped tube 10 does not have a joint in its cross section like a bellows, there is no need for troublesome welding work along the circumferential direction, and stress concentration does not occur as in the welded portion of the cross section. Therefore, there is no problem of causing rupture due to stress concentration. Since the structure is simple and easy to manufacture, the manufacturing cost can be significantly reduced.

[Brief explanation of drawings]

Fig. 1 is a vertical cross-sectional view of a Kuranochi device according to an embodiment of the present invention, and Fig. 2 A and B are ring-shaped tubes used in the device, and Fig. 2 A is a longitudinal cross-sectional view with a part omitted. Side view,
Figure 2B is the same (earth pressure surface diagram, Figure 3 is an explanatory diagram showing the operating status of the ring-shaped tube, Figures 4 and 5 are cross-sectional views of the ring-shaped tube according to other embodiments, Figure 6A) ,
B and C are explanatory diagrams showing an example of a manufacturing process of a ring-shaped tube. 1...Casing, 2...Input shaft, 3...Output shaft,
4. Planetary gear mechanism, 8. Internal gear, 8a...
Rib part, 9...Friction plate, 10...Ring-shaped tube. Agent: Patent Attorney Shin Ogawa − Patent Attorney Ken Noguchi Teru Patent Attorney Kazuhiko Saishita

Claims (1)

[Claims] A planetary gear mechanism is interposed between the input shaft and the output shaft, and the internal gear of this planetary gear mechanism is set in an idle state, and a ring is attached to the rim part protruding from the outer periphery of the internal gear via a friction plate. Tubes having seamless cross-sections are placed opposite each other,
Pressurized fluid can be supplied to the ring-shaped tube by restricting only the tube supporting surface side and the side facing the friction plate, and the tube is expanded by the supply of pressurized fluid to press the rim portion and press the rim portion inside. A clutch device for a planetary gear mechanism, characterized in that a gear can be fixed and stationary.