JPH0311474Y2 - - Google Patents

Description

[Detailed explanation of the idea] (Industrial application field) The present invention relates to a sealing device for a continuously variable transmission.

(Prior Art) A conventional example of a sealing device for this type of continuously variable transmission is shown in FIG. 4, for example. In this conventional example, a movable pulley 42 having a substantially U-shaped cross section and having an outer cylinder part 61 and an inner cylinder part 62 is disposed coaxially and slidably on the shaft part 60 of the fixed pulley 41. constitutes an assembly 43,
An oil sealing chamber 45 is formed between the flange 44 of the fixed pulley 41 and the movable pulley 42, and the oil sealing chamber 45 is sealed by interposing an outer lip packing 48 and an inner lip packing 49 in the gaps 46 and 47 created between the two. are doing.

However, in the case of such a conventional example, the lip portions 51, 5 of the inner and outer lip packings 49, 48
0 is brought into pressure contact with the fixed pulley 41 and the movable pulley 42, allowing the movable pulley 42 to slide while sealing the oil introduced into the oil sealing chamber 45, which causes the following problems. are doing. That is, when the movable pulley 42 slides on the fixed pulley 41 in the axial direction, the lip portions 51, 50 of the inner and outer lip packings 49, 48 and the fixed pulley 41 or the movable pulley 42 move in accordance with the movement of the movable pulley 42. During this period, an action occurs that draws oil in. This drawn-in oil pushes up the lip portions 51, 50 of the inner and outer lip packings 49, 48, forming an extremely thin wedge-shaped oil film, and a portion of this oil film layer slides on the lip portions 51, 50. scraped by the ends of the oil, it accumulates and inevitably causes external leakage of oil. In addition, the fixed pulley 41 and the movable pulley 4
2, the lip parts 51, 5 of the inner and outer lip packings 49, 48
The contact pressure between the fixed pulley 41 or the movable pulley 42 becomes uneven, and no leakage occurs from the portion where the contact pressure is small. Furthermore, if oil leakage occurs as described above, the oil leaking from between the lip part 51 of the inner lip packing 49 and the fixed pulley 41 will be leaked between the inner cylinder part 62 and the shaft part and the fixed pulley 41. The oil reaches the V-shaped groove 55 in which the belt 54 is hung through the sliding surfaces 52 and 53 between the belt 54 and the movable pulley 42, and the oil comes into contact with the belt 54. As a result, there are problems in that the belt 54 may slip due to the oil, or the belt 54 may come into contact with the oil and its deterioration may be accelerated. To prevent this problem, a special oil-resistant belt is usually used, but in this case, the special belt is very expensive and poses a cost problem. Also,
Since oil leakage inevitably occurs as described above, a separate collection mechanism for collecting the leaked oil is required, which poses a problem in that the apparatus becomes complicated.

(Problems to be solved by the invention) Therefore, the present invention was made to solve the conventional problems. By completely sealing both the outer cylindrical part of the movable pulley and the second flange and between the inner cylindrical part of the movable pulley and the shaft part of the fixed pulley,
The purpose is to provide a sealing device for a continuously variable transmission that eliminates oil leakage, prevents belt slippage and accelerated deterioration, and eliminates the need to recover leaked oil.

(Means for Solving the Problems) In order to solve the above problems, the present invention forms a fixed pulley in which the shaft portion is provided with first and second flanges at predetermined intervals, and the shaft of the fixed pulley is A movable pulley having a substantially U-shaped cross section and having an outer cylindrical part and an inner cylindrical part is slidably mounted between the first and second flanges of the part, and the belt is connected by the first flange of the fixed pulley and the movable pulley. The second flange of the fixed pulley and the movable pulley form an oil sealing chamber, and the space between the second flange and the outer cylindrical portion and between the inner cylindrical portion and the shaft portion is formed. A flexible membrane is arranged between the oil sealing chamber and the oil sealing chamber.

(Example) The present invention will be explained below based on the illustrated example. 1 to 3, a disc-shaped movable pulley 4 is coaxially and slidably disposed on a fixed pulley 1 having a pair of flanges 2 and 3 at a predetermined interval. An assembly 5 is constructed. As shown in FIG. 3, this pulley assembly 5 has two sets of the same configuration, and a belt 6 is hung between them. For this purpose, the first flange 2 of the fixed pulley 1 and the movable pulley 4 are opposed to each other, a V-shaped groove 7 is formed therebetween, and the belt 6 is hung in the V-shaped groove 7.

On the other hand, an oil-filled chamber 8 is formed between the movable pulley 4 and the second flange 3 of the fixed pulley 1, and the fixed pulley 1 and the movable pulley 4 are connected by an annular outer diaphragm 11 and an inner diaphragm 12 as flexible membranes. As a result, the gaps 9 and 10 formed between the pulleys 1 and 4 are closed. In this way, the oil-filled chamber 8 is sealed by the outer diaphragm 11 and the inner diaphragm 12. The outer diaphragm 11 is arranged so that the curved part 13 bulges out toward the outside of the oil sealing chamber 8, and the protrusions 14, 1
The movable pulley 4
It is fitted and fixed to the end surface 18' of the outer cylindrical portion 18 protruding from the outer peripheral end thereof and the outer peripheral end side surface 3' of the second flange 3 of the fixed pulley 1 via fixing plates 19 and 20.
One end 16 of this outer diaphragm 11 is
The fixing plate 19 is fitted into a recess 21 cut in the fixing plate 19, and in this state, the fixing plate 19 is fixed to the end face 18' of the outer cylinder part of the movable pulley 4 in the axial direction with bolts or the like. The other end 17 is connected to the outer peripheral end side surface 3' of the second flange 3.
In this state, the fixing plate 20 is fixed in the axial direction to the outer peripheral end side surface 3' of the second flange 3 with bolts or the like. Further, the inner diaphragm 12 is arranged so that the curved portion 23 bulges toward the outside of the oil sealing chamber 8, and the protrusions 24, 2
The movable pulley 4
It fits into the end face 28' of the inner cylinder part 28 protruding from the inner circumferential end of the inner cylinder part 28 and the side face 30' of the annular recess 30 cut in the shaft part 29 of the fixed pulley 1 via the fixing plates 31 and 32. stick. One end 26 of this inner diaphragm 12 is connected to the inner peripheral end surface 2 of the movable pulley 4.
8', and in this state, the fixing plate 31 is fixed in the axial direction to the inner cylinder end face 28' with bolts or the like. The other end 27 fits into a recess 34 cut into the side surface 30' of the annular recess 30, and in this state, the fixing plate 32 is inserted into the annular recess 3.
0 and fixed in the axial direction. In the figure, numeral 35 indicates a communication path that communicates the oil sealing chamber 8 with a hydraulic power source (not shown).

In the above configuration, by changing the amount of oil introduced into the oil sealing chamber 8 from the hydraulic power source via the communication path 35, the pressure inside the oil sealing chamber 8 changes, and the movable pulley 4 is rotated relative to the fixed pulley 1. these fixed pulley 1 and movable pulley 4
Since the pulley diameter of the V-shaped groove 7 formed by the above-mentioned V-shaped groove 7 changes continuously, the rotational speed transmitted via the belt 6 hung on the V-shaped groove 7 changes steplessly. At this time, in order to seal the oil chamber 8, the fixed pulley 1 and the movable pulley 4, which move relatively, are connected to the inner and outer diaphragms 12, 11.
Since it is directly connected via the oil sealing chamber 8
Specifically, between the outer cylinder part 18 and the second flange 3,
Both the inner cylindrical part 28 and the shaft part 29 can be completely sealed, and oil will not leak outside from the oil sealing chamber 8. Even if there is a shake, the amount of eccentricity can be absorbed. Of course, since the inner and outer diaphragms 12 and 11 have flexibility, they do not interfere with the sliding movement of the movable pulley 4 in the axial direction.

Note that, as in the illustrated embodiment, projections 14, 15,
24, 25 are provided, and both ends 16, 17, 2 are provided.
6, 27 to fixed pulley 1 and movable pulley 4
When the inner and outer diaphragms 12, 11 are attached in the axial direction in a fitted state via the fixing plates 19, 20, 31, 32, the inner and outer diaphragms 12, 11 can be attached in a liquid-tight manner, and there is no leakage from the mounting portions. Prevents oil from leaking to the outside.

Further, in the illustrated embodiment, a case has been described in which a diaphragm is used as the flexible membrane, but the invention is not limited to this, and any flexible membrane may be used. Of course.

(Effects of the invention) Since the present invention consists of the above-mentioned configuration and operation,
It is possible to absorb the axial vibration between the fixed pulley and the movable pulley, and the oil-filled chamber, specifically between the outer cylindrical part of the movable pulley and the second flange of the fixed pulley, and between the inner cylindrical part of the movable pulley and the fixed pulley. By completely sealing both the shaft and the shaft with a flexible membrane, oil leakage can be eliminated, preventing belt slippage and accelerated belt deterioration due to leaked oil. , the durability of the belt is improved. Therefore, there is no need to use a very expensive special belt as in the past, and there is no need for a mechanism for collecting leaked oil, so there is no need to increase costs or complicate the device.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal sectional view showing an embodiment of the sealing device for a continuously variable transmission according to the present invention, Fig. 2 is an enlarged view showing the main parts of the device, and Fig. 3 is a schematic diagram of the continuously variable transmission. FIG. 4 is a longitudinal sectional view showing a conventional sealing device for a continuously variable transmission. Explanation of symbols, 1...Fixed pulley, 4...Movable pulley, 6...Belt, 7...V-shaped groove, 11,
12...Diaphragm (flexible membrane).

Claims (1)

[Scope of utility model registration request] A fixed pulley is formed in which a shaft portion is provided with first and second flanges at predetermined intervals, and the shaft portion of the fixed pulley has an outer cylindrical portion and an inner cylindrical portion between the first and second flanges. A substantially U-shaped movable pulley is slidably attached, and the first flange of the fixed pulley and the movable pulley form a V-shaped groove for hanging the belt, and the second flange of the fixed pulley and the movable pulley An oil sealing chamber is formed by forming an oil sealing chamber, and a flexible membrane is arranged between the second flange and the outer cylinder part and between the inner cylinder part and the shaft part to seal the oil sealing chamber. Transmission sealing device.