JPH01261553A - Drive force transmission - Google Patents

Abstract

PURPOSE:To reduce the weight and cost of a drive force transmission by engaging the inner plate of a multi-board clutch with another can engaging body and regulating the mutual displacement of a pair of cam engaging bodies at a specific time thereby reducing the strength of parts. CONSTITUTION:A drive force transmission comprises a rotary housing 21, a rotary shaft 22, a hydraulic pressure producing means 23, an operational piston 24 and a multi-board clutch 25. When the differential rotation between an input shaft 15 and an output shaft 16 reaches to a predetermined level, mutual displacement of a pair of cam engaging bodies 30 is regulated. Consequently, abrupt increase of transmission torque is suppressed thus blocking transmission of excessive torque. By such arrangement, strength of parts can be reduced resulting in reduction of the weight and cost.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention provides a drive system that transmits the rotational power of the input shaft to the output shaft when differential rotation occurs between the input shaft and the output shaft. This invention relates to a force transmission device.

<Prior art> A driving force transmission system that includes a multi-disc clutch that is disposed between a front-wheel drive shaft and a rear-wheel drive shaft and transmits torque between the two shafts, and an operating piston that operates the multi-disc clutch. The device is equipped with a differential pump that discharges pressure oil through relative rotation between the front wheel drive shaft and the rear wheel drive shaft, and the pressure generated by the differential pump is applied to the actuating piston to operate the multi-disc clutch R117. % 14.

In this type of drive power transmission device, if the multi-disc clutch causes long-term sliding friction when the wheels come off, etc., there is a risk that P:I will occur in the multi-disc clutch and damage the clutch plate. .

Conventionally, as a solution to such problems,
DESCRIPTION OF RELATED ART As described in 142945, a driving force transmission device equipped with a lock-up W1 structure using a cam is known.

<Problem to be Solved by the Invention> However, in the above-mentioned known driving force transmission device, the long ag R side has a pair of cam engaging bodies consisting of a V-shaped four-wheel and a ball that engages with this V-shaped concave. The composition is as follows. According to such a lock-up R side, the transmitted torque based on the rise in oil pressure in the oil pressure generating section due to the differential rotation rises gradually as shown by line A in Fig. 5, and reaches a predetermined differential rotation ΔN.
When it reaches 1, the lockup acts on the side and the transmitted torque rises rapidly like a four-line line.

This sudden increase in the transmitted torque of -F continues to increase by 1 along the slope of the V-shaped concave course.

When the rotor is up, the multi-disc clutch is in a directly connected state, so sudden starts and braking will result in an excessive transmission of 1 to 100 lbs. Therefore, it is necessary to increase the strength of the cam engagement body as well as the multi-disc clutch, which results in an increase in weight. Means for Solving the 9 Problems of High Cost The present invention has been made in view of the above-mentioned conventional problems, and has a structure in which: A multi-disc clutch that transmits torque between both shafts, an operating piston that presses the multi-disc clutch, and a hydraulic pressure corresponding to the differential rotation between the input shaft and the output shaft applied to the operating screw. In the driving force transmission device, a housing is connected to one of the input shaft and the output shaft, a rotating shaft rotatably supported by the housing is connected to the other, and The V-shaped concave cam is comprised of a V-shaped concave cam that is relatively rotatably engaged in the circumferential direction and presses the multi-plate clutch by relative rotation, and a convex cam that engages with this V-shaped concave cam. A pair of cam engaging bodies are arranged at both ends of which the convex cam comes into contact and engagement end surfaces are formed to restrict relative displacement, one of the pair of cam engaging bodies is connected to the rotating shaft, and the other is connected to the rotating shaft. A set of outer plates of the multi-disc clutch is fitted to the rotating shaft for relative rotation i1, and an inner plate of the multi-disc clutch is disposed between each of these outer plates. The cam engaging body is engaged with the other cam engaging body.

With the above configuration, when the relative rotational speed difference between the input shaft and the output shaft increases, the friction engagement force of the multi-disc clutch increases, and the transmitted torque exceeds the bias set by the disc spring, the pair The cam engaging body rotates relative to each other and is relatively displaced in the axial direction by the cam action. Due to the relative axial displacement of the pair of cam engaging bodies, the inner plate is pressed against the outer plate 1, and the outer plate and the inner plate are coupled in a substantially direct connection state. As a result, the torque transmitted by the multi-disc clutch increases rapidly, making it easier to escape from mud etc., and the slippage between the outer plate and inner plate is increased by 1117%.
This prevents damage to both plates. In this case, the pair of cam engaging bodies transmits!・When the torque suddenly increases to a predetermined value, there is a relative displacement, but beyond that, the relative displacement is regulated and the increase in the transmitted torque is suppressed.

<Example> Embodiments of the present invention will be described below based on the drawings.

In FIG. 3, 10 is the engine, 11 is the transmission, and 13 is the front i! III differential device, 14 is a rear wheel differential device, 15 is a front Va side drive shaft (input shaft), 16 is a rear wheel side drive shaft (output shaft), 17 is a front wheel, 18 is a rear wheel, 20 is a front wheel The output of the engine 10 is shown as a driving force transmission device provided between the side drive shaft 15 and the f&4 side drive shaft 16, and the output of the engine 10 is transmitted to the front wheel differential device 13 via the transmission 11.
In addition to driving the front wheels 17, the driving shaft 1
5, the rotation is transmitted to the rear wheel drive shaft 16 via the drive force transmission device, and the rotation is transmitted to the rear wheel drive shaft 16 through the drive force transmission device. 18.

As shown in FIG. 1, the driving force transmission device 20 includes a rotary housing 21, a rotary shaft 22 which extends vertically through the rotary housing 21 and is rotatably supported, and a rotary housing sink 21 and a rotary shaft 22. A hydraulic pressure generating means 23 that generates hydraulic pressure according to the differential rotation between the hydraulic pressure generating means 23, an operating piston 24 to which the hydraulic pressure generated by the hydraulic pressure generating means 23 is applied, and a hydraulic piston 24 that is frictionally engaged by the pressing force of the operating piston 24. It is mainly composed of a multi-disc clutch 25 and a multi-disc clutch 25.

The front wheel drive shaft 15 is integrally connected to one end of the IrX rotary housing 21, and the rear wheel drive shaft 16 is spline-engaged within the rotary shaft 22. A lubricating oil chamber 27 is formed concentrically with the rotating shaft 22, and this il? J oil chamber 27
One end opening is closed with an end cover 28. Inside the lubricating oil chamber 27, a clutch hub 31 constituting one of the pair of cam engaging bodies 30 is rotatably and axially movably supported on the outer periphery of the rotating shaft 22.
Engagement balls 32 forming convex cams on the end surfaces are held at equal angular intervals on the circumference. 'JA' of Franchise Hub 31
A torque receiving body 31a is provided at + to sandwich the multi-disc clutch 25 and the operating piston 24.

Further, a cam play 1 and 33 forming the other of the pair of cam engaging bodies 30 is spline-engaged with the outer periphery of the rotating shaft 22. On the surface of the cam plate 33 facing the end surface of the clutch hub 31, cams 7f434 forming the same number of V-shaped concave cams that engage with the engagement balls 32 are formed at equal angular intervals on the circumference. . As shown in FIG. 4, this cam plate 34 has a V-shaped shape along the circumferential direction, and engagement end surfaces 34a are formed at both ends thereof in a direction perpendicular to the rotational direction of the cam plate 33. has been done. Each of the engaging balls 32 is normally engaged with the center of the V-shaped cam 34 by the force of a disc spring 35 interposed between the cam plate 33 and the clutch hub 31.

Furthermore, inside the lubricating oil chamber 27, there are a plurality of outer plates 37 and inner plates 3 that constitute the multi-plate clutch 25.
The outer plate 37 is connected to the inner periphery of the rotary housing 21 by a spline, and the inner plate 38 is engaged to the outer periphery of the clutch hub 31 by a spline.

A cylindrical space 40 limited in the axial direction is formed between the working piston 24 and the inner end of the rotary housing 21, and a rotor having a wall thickness slightly smaller than the axial dimension of the space 40 is formed in the space 40. 41 is housed in a slidable manner. As shown in FIG. 2, this rotor 41 has a center portion splined to the outer periphery of the rotating shaft 22, and has two blades 42 extending in the diametrical direction. As a result, the space 40 is divided into a plurality of spaces around the circumference by a plurality of blades 42, and each of these spaces is filled with high viscosity oil such as silicone oil. The oil pressure generating means 23 is constituted by a rotor 41 having a blade 42 housed in this space 40 and high viscosity oil.

In the above configuration, the front wheel side drive shaft 15 and the rear wheel 0-1
When the drive shaft 16 rotates relatively and the rotor 41 (111f) rotates relatively within the rotating housing 22, the high viscosity oil filled in the space 40 flows between the two closely spaced surfaces at a flow rate according to the rotational speed difference. be forcibly moved. At this time, an internal pressure proportional to the rotational speed of the rotor 41 is generated within the space 40 due to viscous friction between the rotating housing 21 and both end surfaces of the operating piston 24 . That is, for example, when the blade 42 rotates relative to the rotary housing 21 in the direction of the arrow in FIG.
& If the continuing blade side is B, it is highest at point A, and B
The pressure distribution is lowest at the point, and the blade 4 is in the space 40.
2 is generated, and this pressure acts on the actuating piston 24 and presses the multi-disc clutch 25.

Therefore, a plurality of outer plates 37 and inner plates 3
8 is engaged with a pressing force corresponding to the hydraulic pressure acting on the operating piston 24, and rotational torque is transmitted from the front wheel drive shaft 15 to the rear wheel drive shaft 16 via the multi-disc clutch 25. >Becomes a driving state. In this case, multi-plate clutch 2
The rotational torque transmitted to the inner brake 1 of 5 at 38 is:
Clutch hub 31, engagement ball 32, and cam plate 3
3 to the rotating shaft 22. Such a result,
Even if the front wheels 17 or the rear wheels 18 get stuck in mud or the like and spin, it is possible to escape from the mud or the like.

By the way, if this escape does not go as planned and you step on the accelerator to increase the engine speed to escape,
Di? @1tPI The differential rotation (relative rotational speed difference) between the drive shaft 15 and the rear wheel drive shaft 16 increases, and the multi-disc clutch 2
5 increases, and the transmitted torque also increases. However, as shown in FIG. 5, when the differential rotation reaches ΔN1 and the transmitted torque (a) exceeds the bias set by the disc spring 35, the clutch hub 31 and clutch plate 1
33 rotates relatively against the disk spring 35, and the engagement ball 3
2 rides on the cam gear 34, and as a result, the clutch hub 31
is displaced in the axial direction with respect to the clutch plate 33, and presses the multi-disc clutch 25 toward the actuating piston 24 with its torque receiving body 31a. Due to this axial displacement of the clutch hub 31, the outer plate 37 and the inner plate 3
8 is connected in a substantially direct connection state and locked up. As a result, the torque delivered by the multi-disc clutch 25 rapidly increases after reaching a predetermined differential rotation ΔNl, as shown in (b) of the torque transmission characteristic ν in FIG. At the same time as making it easier to escape from the mud, etc., outer play 1 and 3
Sliding friction between the inner plate 7 and the inner plate 38 is suppressed to prevent loss of both plates. However, the transmission torque increases rapidly as shown in (b) when the differential rotation increases to △N2, that is, when the multi-disc clutch 25 is almost directly connected, the transmission torque increases as shown in (c). be done.

This is due to the relative displacement between the clutch hub 31 and the clutch plate 33 during the differential rotation ΔN2, and the engagement ball 32 comes into contact with the engagement end surface 34a formed on the cam shaft 34, thereby reducing the relative displacement between the clutch hub 31 and the clutch plate 33. This is because the pressing force of -F is no longer applied to the multi-disc clutch 25 in order to regulate the force.

In the embodiment described above, the hydraulic pressure acting on the actuating piston 24 is a hydraulic pressure generating means that forcibly moves high viscosity oil using a blade, but a conventionally well-known differential pump may also be used.

<Effects of the Invention> 4. As described above, the present invention has a cam that is relatively rotatably engaged in the housing connected to one of the input shaft and the output shaft in the circumferential direction, and presses the multi-disc clutch by the relative rotation. A pair of cam 1 system combinations are arranged, one of the pair of cam 1 system combinations is connected to a rotating shaft rotatably supported by the housing, the other is fitted to the rotating shaft with relative rotation = r ability, and the inside of the housing is The outer plates of the multi-disc clutch are engaged with the outer plates of the multi-disc clutch, and the inner plates of the multi-disc clutch disposed between these outer plates are engaged with the other cam engaging body of the input shaft and the output shaft. Since the configuration is such that the relative displacement of the pair of cam engaging bodies is regulated when the differential rotation reaches a predetermined value or more, a sudden increase in the transmitted torque is suppressed within a predetermined range of 1 to 1 torque, and an excessive 1 - Prevents luke transmission.

This makes it possible to reduce the strength of components such as the multi-disc clutch and the cam engaging body, which has the effect of reducing weight and cost.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention, and FIG. 1 is a sectional view of a driving force transmission device, FIG. 2 is a sectional view taken along the line ■-■ in FIG. 1, and FIG. 3 is a schematic diagram of a four-wheel drive vehicle. , FIG. 1 is a sectional view of the main part of the lock-up mechanism, and FIG. 5 is a diagram showing transmission torque characteristics with respect to differential rotation. 15... Front wheel side drive shaft, 16... Rear wheel side drive shaft, 2
1... Rotating housing, 22... Rotating shaft, 23...
- Hydraulic pressure generating means, 24... Working piston, 25...
Multi-plate clutch, 30... Cam 1 system combination, 31... Clutch hub, 32... End ball, 33... Clutch plate, 34... Cam holder, 34a... Engagement end surface , 37...outer plate, 38...inner plate.

Claims (1)

[Claims] (1) Differential rotation between a multi-disc clutch placed between an input shaft and an output shaft and transmitting torque between the two shafts, an actuating piston that presses the multi-disc clutch, and the input shaft and output shaft. In the driving force transmission device, the driving force transmission device includes a hydraulic pressure generating means for applying a hydraulic pressure to the actuating piston according to the working piston, in which a housing is connected to one of the input shaft and the output shaft, and a rotating shaft rotatably supported by the housing is connected to the other one of the input shaft and the output shaft. A V-shaped concave cam that connects the shaft, engages with the housing so as to be relatively rotatable in the circumferential direction, and presses the multi-disc clutch by the relative rotation, and a convex cam that engages with the V-shaped concave cam. A pair of cam engaging bodies are arranged in which the convex cam comes into contact with both ends of the V-shaped concave cam to restrict relative displacement, and one of the pair of cam engaging bodies is arranged. The multi-disc clutch is connected to the rotating shaft, the other is relatively rotatably fitted to the rotating shaft, the outer plate of the multi-disc clutch is engaged with the inner periphery of the housing, and the multi-disc clutch is disposed between each of the outer plates. A driving force transmission device in which an inner plate of a plate clutch is engaged with the other cam engaging body.