JPH0125790Y2 - - Google Patents

Description

[Detailed description of the invention] This invention relates to a device for preventing rotation of a wet clutch, which is used for driving vehicles such as tractors, working machines, etc. Reliably brakes the drag torque when
In addition to preventing drag torque from being transmitted to the output shaft, the anti-rotation device is compactly incorporated inside the clutch unit without providing a fixed end on the mating housing or case, so that accurate operating characteristics can be obtained. It is intended to.

In devices that use a wet clutch, the clutch is often turned off and the drag torque, that is, the output side of the clutch is turned, due to the friction material biting into the mating plate or the presence of oil between the friction material and the mating plate. force is generated. Therefore, if the reduction ratio from the clutch part to the vehicle wheel is large, the vehicle may run even when the clutch is off, and if the clutch is for work equipment, the work equipment may not stop, resulting in safety and work problems. easy.

As a countermeasure to this problem, conventionally, a lug (protrusion) was provided on the outer periphery of each driven plate of the clutch, and a return rubber piece was attached between the adjacent lugs to forcibly separate the adjacent driven plates when the clutch was released. However, the anti-rotation function is not perfect, and drag torque is likely to occur, especially when the oil is highly viscous. Conventionally, there is a system in which a part of the clutch case, on which the driven plate is latched, is forcibly pressed against the clutch housing side member when the clutch is off, to provide braking force, but in that case, the clutch case and the mating housing Since it is difficult to maintain the positional relationship accurately, the entrainment prevention function tends to become unstable.

The present invention solves the above-mentioned conventional problems and provides a device that is simple in structure, compact, and efficient, and can reliably prevent entrainment.

Next, examples will be shown. In FIG. 1, which shows a longitudinal section of a clutch unit to which the present invention is applied, the upper half from the center line O--O corresponds to the clutch-on (connection) time, and the lower half corresponds to the clutch-off time. First of all
In the upper half of the figure, the input flange 1 is provided with internal splines 2 on the outer periphery, and the splines 2 are connected to the hub 3.
The hub 3 is fitted into a small-diameter cylindrical surface 7 of an output shaft 6 via a centrally fixed bushing 5, and is rotatable on the cylindrical surface 7. A thrust washer 8 and a thrust bearing 10 are arranged on the cylindrical surface 7 on both sides of the hub 3, the thrust washer 8 engages with a step 12 between the cylindrical surface 7 and the spline 11, and the thrust bearing 10 is a snap spring. 13 to fix the axial position of the hub 3.

A plurality of drive plates 15 are engaged with the external spline 4 of the hub 3 at the lugs 15a on the inner circumference, and therefore the drive plates 15 are only able to slide relative to the hub 3 in the direction of the clutch centerline O-O. . A snap ring 16 and a back plate 17 are placed on the external spline 4 between the input flange 1 and the drive plate 15 in order from the internal spline 2 side.
is installed. Adjacent drive plate 1
The driven plate 19 disposed between the drive plates 15 and 15 and between one drive plate 15 and the clutch case 18 engages with the axial groove 20 (latching part) of the clutch case 18 at the lug 19a provided on the outer periphery. Therefore, the driven plate 19 can only slide freely relative to the clutch case 18. The clutch case 18 meshes with the spline 11 at the internal spline 21 and is therefore slidable on the output shaft 6.

The central cylindrical boss 23 of the clutch case 18 is
two grooves 2 extending axially at the opposite end of the hub 3;
4, and the two annular drive plates 25 fitted on the bosses 23 have lug 25a portions on the inner periphery fitted in the grooves 24, so that the drive plates 25 can only slide freely on the bosses 23. . Bearing 2 fitted to the outer periphery of the middle part of the clutch case 18
8 is fixed in its axial position on the clutch case 18 by a stepped portion 29 and a snap spring 30, and a sleeve 31 fitted into the outer race of the bearing 28 is fixed by two lugs 32 provided on the outer periphery.
(Figure 2) Release fork (not shown)
The rotation is prevented by the release fork. Axial hole 33 provided in sleeve 31
(Fig. 1), a pin 34 is press-fitted into the pin 34, and this pin 34 has a groove 37 formed in an outer peripheral lug 36 of an annular brake plate 35 and opened radially outward.
The brake plate 35 is disposed between the drive plates 25 and 26. Therefore, the brake plate 35 can only slide freely relative to the sleeve 31.

A second spring guide 40 and a first spring guide 39 are sequentially fitted with splines on the output shaft 6 adjacent to the drive plate 26, and a first
The spring guide 39 is engaged with a snap spring 41 on the output shaft 6 and is prevented from moving away from the second spring guide 40 (to the right in FIG. 1). Annular step portions 41 and 42 are provided on the outer peripheries of both spring guides 39 and 40 at positions facing each other.
is provided, and the inner peripheral edges of two cone-shaped Belleville springs 43 that open toward the bearing 28 side are engaged with the step portion 41 in a free state, and the step portion 4
2 engages with the inner peripheral edge of a cone-shaped Belleville spring 44 that opens toward the Belleville spring 43 side in a free state, and both Belleville springs 43, 44
The outer periphery of is pressed into contact with a spacer ring 45. Therefore, the second spring guide 40 receives elasticity from the Belleville springs 43 and 44 in a direction in which it is normally brought into pressure contact with the boss 23 (toward the left in FIG. 1).

Holes 4 parallel to the clutch centerline O-O are provided at three equally spaced locations on the same circumference of the second spring guide 40.
7 is open, and a parallel pin 48 of the same length is slidably fitted into this hole 47, with one end of the pin 48 facing the drive plate 26 and the other end facing the annular spring bearing plate 49. There is. Spring receiving plate 49
is supported on the output shaft 6 between the spring guides 39 and 40, and two plate springs 50 are arranged between the plate 49 and the first spring guide 39. When the clutch is engaged as shown in the upper half of FIG. Parallel pin 48 and spring bearing plate 4
It is shown between 9 and 9.

In the upper half of FIG. 1, the elasticity of the Belleville springs 43 and 44 is
It is transmitted to the clutch case 18 via the cylindrical boss 23, and the clutch case 18 moves forward in the direction of arrow F.
The driven plate 19 is pressed against the snap spring 16. Therefore, the rotational force of the engine is generated by input flange 1, splines 2 and 4, and drive plate 1.
5. Driven plate 19, clutch case 1
8, is transmitted to the output shaft 6 via splines 21 and 22. This state corresponds to the set position shown in FIG. 3, and the amount of deflection and load of the Belleville springs 43, 44 at this time are given by point _P1 on curve _S1 .

Next, when the clutch is operated and the sleeve 31 is moved backward in the opposite F direction against the elasticity of the Belleville springs 43 and 44, the movement of the sleeve 31 is transmitted to the clutch case 18 via the bearing 28 and the snap spring 30. moves backward in the reverse F direction, the pressure between the driven plate 19 and the drive plate 15 decreases, and the clutch begins to disengage. The sleeve 31 moves by A and reaches the point in Figure 3.
When P ₂ (brake activation position) is reached, parallel pin 4
8 disappears, the disc spring 50 begins to be compressed between the snap spring 30 and the first spring guide 39, the load of the disc spring 50 acts between the drive plates 25, 26 and the brake plate 35, and the brake Since the plate 35 is a stationary member in the rotational direction, the drive plates 25 and 26 begin to receive braking force. The brake load due to the disc spring 50 is applied to the curve S ₁ at the end of the release stroke L ₁ as shown in the curve S ₂ in FIG. The brake torque applied to the drive plates 25, 26 from the brake plate 35 is designed to be greater than the drag torque applied to the clutch case 18, at least at the end of the clutch release stroke. Therefore, there is no possibility that the output shaft 6 will rotate due to drag torque when the clutch is off.

As explained above, in the present invention, (1) the clutch case 1 is
Since the drag torque received by the clutch 8 is reliably braked and the drag torque is not transmitted to the output shaft 6, the problem of the vehicle running or the working machine not stopping during the clutch off is solved.

(2) A brake disc spring 50 is assembled between the first and second spring guides 39 and 40, and the brake plate 35 and drive plates 25 and 26 are assembled between the snap spring 30 and the second spring guide 4.
Since it is incorporated between 0 and 0, it is compact.

(3) Since the brake plate 35 is connected to the sleeve 31, which is prevented from rotating, via a pin 34 etc. so that it can move integrally (slide freely), it can be prevented from rotating only inside the clutch unit. Since the device can be configured easily and there is no need to provide a fixed end on the housing or case of the other party to determine the positional relationship with a particularly high precision, the anti-corroboration function is stabilized. In other words, the brake activation position (see Figure 3) during the clutch release stroke can be accurately determined, and the load deflection curve _S2 after applying the brake load with the disc spring 50 will not vary from vehicle to vehicle, ensuring quality. becomes stable. The brake capacity is the load of the disc spring 50,
It can be changed by changing the number of brake plates 35 or by changing the number of brake plates 35. Therefore, the brake capacity can be set freely, and if there is a switching operation after the clutch, it is possible to set the torque to match it.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional side view of a wet clutch to which the present invention is applied, with the upper half showing the clutch in the engaged state and the lower half showing the clutch in the off state. FIG. 2 is a partial view of FIG. 1 in the direction of the − arrow, and FIG. 3 is a load-deflection curve diagram. 6... Output shaft, 18... Clutch case, 19
... Driven plate, 20, 24 ... Groove (latching part), 25, 26 ... Drive plate, 28 ...
...bearing, 30...snat spring, 31...
...Sleeve, 35...Brake plate, 39,
40...first and second spring guides, 43,4
4...Belleville spring, 47...hole, 48...
...Parallel pin, 49...Spring bearing plate, 50...
Disc spring.

Claims (1)

[Scope of utility model registration request] An output shaft, a clutch case that is spline-fitted onto the output shaft and has a hook for the clutch's driven plate at one end and a hook for the brake drive plate at the other end, and is fixed to the outer periphery of the middle part of the clutch case with a snap spring. a sleeve supported on the bearing and slidable only; a first spring guide fixed on the output shaft; and a second spring guide spline-fitted on the output shaft between the bearing and the first spring guide. spring guide and
A pair of Belleville springs whose inner peripheries are supported by the outer peripheries of the first and second spring guides and whose outer peripheries are in pressure contact, and which are slidably latched to the latching portion between the snap spring and the second spring guide. a plurality of drive plates, a brake plate that is sandwiched between the drive plates and moves integrally with the sleeve, a spring bearing plate and a disc spring that are arranged between the first and second spring guides in order from the second spring guide side, and a drive. It consists of parallel pins that fit into multiple holes drilled parallel to the output shaft in the second spring guide opposite the plate and spring bearing plate, and the clutch case moves the second spring guide toward the first spring guide. A device for preventing rotation of a wet type clutch, characterized in that a drive plate and a brake plate are brought into pressure contact with each other by receiving the elasticity of a disc spring via a pin at the end of a clutch release stroke.