JPH0542264Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a multistage clutch suitable for being installed in the drive system of an automobile equipped with a diesel engine.

(Prior Art) In this type of drive system, the power of the engine is generally input from its output shaft to a transmission via a flywheel and a multi-stage clutch.

An example of a conventional multi-stage clutch of this type is shown in FIGS. 5 and 6, in which 1 is an engine crankshaft, 2 is
is a flywheel fixed to the crankshaft 1, 3
is a multi-stage clutch, 4 is a drive shaft, one end of which is supported by the crankshaft 1 via a bearing 5,
The other end is connected to a transmission (not shown). The clutch 3 includes a clutch plate 6 pressed against the flywheel 2 and a hub 10 wedged onto the drive shaft 4.
The torsional characteristics between the two damp and absorb the torsional vibration of the drive system and the accompanying resonance. The hub 10 includes a cylindrical portion 10a spline-fitted to the drive shaft 4, and a disk portion 10 extending perpendicularly from the outer circumference of the cylindrical portion 10a.
b, and the disk portion 10b is the first friction member 26
It is held between a pair of friction plates 7 via. The pair of friction plates 7 are fixed at their outer peripheral edges to an annular torque plate 8 disposed on the outer peripheral side of the disk portion 10b by pins 16. Further, the inner peripheral outer surfaces of the pair of friction plates 7 are brought into contact with a second friction member 27, and the outer surfaces of this second friction member 27 are connected to the clutch plate 6 and the back-up plate 12.
It is in contact with the inner surface of the inner periphery. The clutch plate 6 and the backup plate 12 are connected to each other by pins 11 at their outer peripheral edges, and the clutch plate 6 and the backup plate 12 connect four second torsions on the same circumference at predetermined intervals. A spring 13 is clamped. This second torsion spring 13 is disposed within a window 8a formed in the torque plate 8, and its both ends are attached to the end walls of the window 8a when no torsion torque is applied between the clutch plate 6 and the torque plate 8. The clutch plate 6 and the torque plate 8b are opposite to each other with an interval of +θ _p and −θ _p apart from each other.
A torsion torque is applied between the two end walls 8b, and when the two rotate relative to each other, they come into contact with one of the end walls 8b. Further, the disk portion 10b of the hub 10
The first
The first torsion spring 14 is disposed within the window 7a formed in the friction plate 7, and the first torsion spring 14
Both ends of the torsion spring 14 are always open to the window 7a.
are in contact with the end walls 7b, respectively. Reference numeral 18 denotes a cushion plate, which is fixed to the outer periphery of the clutch plate 6 with a pin 19.
Facings 20 are fastened to both the front and back sides of 8 with screws 21. Reference numeral 22 denotes a pressure plate, which is pressed against the facing 20 by a compression spring 24 interposed between the back surface of the clutch 3 and the clutch cover 23 when the clutch 3 is engaged. 25 is a ring gear provided on the outer periphery of the flywheel 2. FIG. 7 shows a conceptual diagram of this multi-stage clutch.

When the crankshaft 1 rotates while torsionally vibrating with the clutch 3 in the engaged state, the torsional torque is applied to the clutch plate 6 and the pin 11 via the flywheel 2, facing 20, cushion plate 18, and pin 19. The signal is transmitted to the connected backup plate 12. The torque is then transmitted from the clutch plate 6 and backup plate 12 to the torque plate 8 via the second torsion spring 13 and second friction member 27.
Next, the torque is transmitted to a pair of friction plates 7 connected to this torque plate 8 by a pin 16, and further from this pair of friction plates 7 via a first torsion spring 14 and a first friction member 26. The signal is transmitted to the hub 10. At this time, first, the friction plate 7 and the torque plate 8 fixed thereto by the pin 16 are connected to the first torsion spring 14 having a small spring constant.
rotationally displaced relative to the hub 10 against the elastic force of the first friction member 26 and the friction force of the first friction member 26 . 1st
When the torsion spring 14 is compressed by a predetermined amount, that is, the angle +θ _p or −θ _p , it resists the elastic force of the second torsion spring 13 having a large spring constant and the second friction member 27. The clutch plate 6 and the backup plate 12 fixed thereto by a pin 11 are rotationally displaced relative to the friction plate 7 and the torque plate 8.

Thus, the first and second friction members 26, 27
and first and second torsion springs 1
4 and 13, the multi-stage clutch 3 exhibits torsional characteristics as shown in FIG.

In this multi-stage clutch 3, in order to prevent the first torsion spring 14 from surging, the first torsion spring 14 is preset by a certain amount (for example, about 0.3 to 0.5 mm).
Adjacent projections 10c of hub 10 in a compressed state
The friction plate 7 is assembled so as to be sandwiched between the friction plate 7 and the end wall 7b of the window 7a of the friction plate 7.

Further, when no torsion torque acts between the clutch plate 6 and the hub 10 and the relative torsion angle between them is zero, the second torsion spring 13 is located at the center of the window 8a. Both ends do not come into contact with the end wall 8b of the window 8a, and are +θ _p and -, respectively.
It faces the end wall 8b at an interval of θ _p .

Therefore, when the torsion torque is small, such as when the engine is idling or when the automobile is running at a constant speed, the first torsion spring 14 and the first friction member 26 are
Power is transmitted through the 8th point of operation.
It is located within the first stage spring region a in the figure. When the torsional torque is large during acceleration or deceleration of the automobile, power is transmitted via the second torsion spring 13 and the second friction member 27, and the operating point at that time is 2 in FIG.
It is within step spring region b.

(Problems to be Solved by the Invention) In this type of drive system, measures against noise during idling are one of the most important vibration and noise issues.
This idle noise is an abnormal noise emitted from the transmission case when the transmission is in the neutral position and the engine is kept at idling speed with the clutch 3 in contact, and is also called idle rattle noise. This idle rattle noise is mainly caused by nonlinear torsional vibration of the drive system, which generates tooth striking force within the transmission, and this tooth striking force vibrates the transmission case at the bearing section, generating noise.

However, in the above conventional multi-stage clutch,
When a spring with an extremely small spring constant is used as the first torsion spring 14 to reduce idle noise, and when the first friction member 26 that provides an extremely small first stage hysteresis torque is used, the engine During idle rotation, the operating points of the first stage springs are shown in FIG. 8, a and 2.
There was a problem in that the engine went over the step at the boundary of the step spring region b and entered the second step spring region b, and the impact generated when crossing the step increased the idling noise.

(Means for solving the problem) The present invention was proposed to solve the above problem, and its gist is that multiple types of spring constants with different spring constants are used between the clutch plate and the hub. In a multi-stage clutch in which a torsion spring is interposed, a large diameter portion is provided on a stud pin that interconnects a pair of friction plates that are interlocked and connected to the hub via a first torsion spring and a first friction member. and form a small diameter part,
A rubber base consisting of a base with a smaller diameter than the large diameter part and a protrusion with a larger diameter than the large diameter part is attached to the small diameter part of the stud pin, and the protrusion allows the clutch plate and hub to rotate relative to each other. The multi-stage clutch is characterized in that when the clutch moves from the first stage spring region to the second stage spring region, it comes into contact with an end wall of a window formed in the hub and is compressed and deformed.

(Function) Since the present invention has the above-mentioned configuration, when the clutch plate and the hub are relatively rotated by a predetermined amount while contracting the first torsion spring, the protrusion of the rubber material moves toward the edge of the window. It comes into contact with a wall and undergoes compression deformation. As a result, the compressive deformation of the protrusion of the rubber material imparts a bridging-like hysteresis torque to the boundary between the first-stage spring region and the second-stage spring region to smoothly connect them to each other. Therefore, when the engine is idling, the operating point smoothly transitions from the first stage spring region to the second stage spring region.

(Embodiment) An embodiment of the present invention is shown in FIGS. 1 to 4. 1 to 3, 30 is a hub, 31 and 32 are friction plates, 33 is a clutch plate, 34 is a backup plate, 35 is a second torsion spring, and 36 is a clutch via a cushion plate 37. A facing fixed to the plate 33; 38 a stopper pin interconnecting the clutch plate 33 and the backup plate 34 at their outer peripheries;
9 is a stud pin that interconnects the friction plates 31 and 32; 40 is a disc portion 3 of the hub 30;
a first friction member interposed between the outer surface of the friction plate 31 and the inner surface of the friction plate 31;
41 is a second friction member interposed between the outer surface of the friction plate 31 and the inner surface of the clutch plate 33; 42 is a first thrust spring; The friction member 44 is pressed against the disk portion 30a. 4
A second thrust spring 5 presses a second friction member 47 against the friction plate 32 via a second thrust plate 46.

As is clear from FIGS. 2 and 3, the stud pin 39 is disposed within an arcuate window 49 formed in the disk portion 30a of the hub 30, and has a small diameter portion in the center and large diameter portions 39a at both ends. ing. A rubber material 50 consisting of a base portion having a smaller diameter than the large diameter portion 39a and a projection portion 50a having a larger diameter than the large diameter portion is attached to this central small diameter portion by baking the base portion.

Therefore, when the crankshaft rotates while torsionally vibrating while the clutch is engaged, the clutch plate 33 and the hub 30 are relatively rotationally displaced due to the torsional torque. At this time, while the torsional torque is small, the friction plates 31 and 32 first resist the elastic force of the first torsion spring with a small spring constant and the frictional force of the first friction members 40 and 44, and The torsion spring is rotated and displaced relative to the hub 30 while being compressed. and,
The large diameter portions 39a at both ends of the stud pin 39 that connect the friction plates 31 and 32 by θ ₁ degree in the forward direction or θ ₂ degrees in the reverse direction are connected to the windows 4.
The protrusion 50a of the rubber material 50 contacts the end wall 49a or 49b and is compressively deformed within the range of an angle Δθ (for example, about 1°) before contacting the end wall 49a or 49b of the rubber member 50. Large diameter portions 39 at both ends of stud pin 39
a comes into contact with the end wall 49a or 49b of the window 49, the friction plates 31, 32
Therefore, this stud pin 39 functions as a stopper that restricts the relative rotational displacement between the friction plates 31, 32 and the hub 30.

The large diameter portions 39a at both ends of the stud pin 39 are windows 49.
If the torsional torque increases after contacting the end wall 49a or 49b, the torsional force will be increased against the elastic force of the second torsion spring 35 with a large spring constant and the frictional force of the second friction members 41, 47. While compressing the second torsion spring 35, the clutch plate 33 and the backup plate 34 connected thereto via the stopper pin 38 are rotationally displaced relative to the friction plates 31, 32. Then, when the stopper pin 38 comes into contact with an end wall (not shown) provided on the friction plates 31, 32, the clutch plate 33 and the backup plate
It does not rotate relative to.

Thus, while compressing the first torsion spring, the clutch plate 33 and hub 30 are relatively displaced by an angle θ ₁ in the positive direction or by an angle θ ₂ in the opposite direction, and the large diameter portions 39a at both ends of the stud pin 39 are opened. 4
The protrusion 50a of the rubber material 50 provided on the stud pin 39 in the range of angle Δθ immediately before contacting the end wall 49a or 49b of the stud pin 39 contacts the end wall 49a or 49
This protrusion 50 is compressed and deformed by contacting b.
Due to the compressive deformation of a, as shown in the torsion characteristic diagram in Fig. 4, a bridge-like hysteresis occurs that connects the two spring regions immediately before the clutch operating point shifts from the first stage spring region a to the second stage spring region b. Torque Hc is given.

Thus, when the engine is idling, the actuation point of the clutch smoothly transitions from the first stage spring region a to the second stage spring region b. Since there is no step to climb over, there is no impact.

Since the stud pin 39 is assembled with high precision so as to function as a stopper for regulating relative rotational displacement between the friction plates 31, 32 and the hub 30, the protrusion 50a protrudes from the large diameter portion 39a at both ends of the stud pin 39. By setting the amount accurately, a bridge-like hysteresis torque can be applied accurately just before the clutch operating point shifts from the first stage spring region a to the second stage spring region b.
In addition, the protrusion 50a is only compressed and deformed and does not come into sliding contact with other members, and after the protrusion 50a is compressed and deformed, no torsional torque is applied to it, so that the protrusion 50a does not wear out or break. Nor. Furthermore, a protrusion 50a is added to the existing stud pin 39.
Since it is only necessary to provide the rubber material 50 having the following properties, the structure is extremely simple and can be manufactured at low cost, and it can also be easily applied to an existing multi-stage clutch by replacing the stud pin. Note that if the engine rotates only in the forward direction during idle rotation, the projection 50a that contacts the end wall 49b can be omitted.

(Effects of the invention) In the present invention, a large diameter portion and a small diameter portion are provided on a stud pin that interconnects a pair of friction plates that are interlocked and connected to a hub via a first torsion spring and a first friction member. A base of a rubber material consisting of a base of a smaller diameter part than the large diameter part and a protrusion larger in diameter than the large diameter part is attached to the small diameter part of the stud pin, and the protrusion is arranged so that the clutch plate and the hub are relative to each other. When moving from the first stage spring region to the second stage spring region by rotational displacement, the hub is compressed and deformed by contacting the end wall of the window bored in the hub, so that the difference between the first stage spring region and the second stage spring region is A bridge-like hysteresis torque can be applied to the boundary due to compressive deformation of the protrusion of the rubber material. Therefore, when the engine is idling, the operating point of the multi-stage clutch smoothly transitions from the first-stage spring region to the second-stage spring region, and it is not possible to overcome the step between the first-stage spring region and the second-stage spring region as in the conventional case. Therefore, the impact when climbing over this step can be alleviated. Furthermore, since the spring constant of the first torsion spring can be made extremely small and the first hysteresis torque can be made extremely small, idling noise can be made extremely small. Furthermore, the structure is extremely simple and can be manufactured at low cost, and it can be easily applied to existing multi-stage clutches without requiring any special changes.

[Brief explanation of the drawing]

1 to 4 show embodiments of the present invention,
Figure 1 is a partial sectional view, Figure 2 is a - of Figure 1.
A partial cross-sectional view along the line, FIG.
4 is a torsional characteristic diagram zoomed in the direction of torsional torque, and FIGS. 4 to 8 show an example of a conventional multi-stage clutch,
FIG. 5 is a longitudinal sectional view, FIG. 6 is a partially cutaway front view, FIG. 7 is a conceptual diagram, and FIG. 8 is a torsional characteristic diagram. Clutch plate...33, Second torsion spring...35, Friction plate...
31, 32, stud pin...39, window...4
9. End wall...49a, 49b, elastic body...50.

Claims (1)

[Scope of utility model registration request] In a multi-stage clutch in which a plurality of types of torsion springs having different spring constants are interposed between a clutch plate and a hub, the clutch is interlocked and connected to the hub via a first torsion spring and a first friction member. A stud pin that interconnects a pair of friction plates is formed with a large diameter portion and a small diameter portion, and a base made of a rubber material consisting of a base portion with a smaller diameter than the large diameter portion and a projection portion with a larger diameter than the large diameter portion is attached to the stud pin. The protrusion contacts the end wall of the window formed in the hub when the clutch plate and the hub undergo relative rotational displacement and transition from the first stage spring area to the second stage spring area. A multi-stage clutch that is characterized by compressive deformation.