JPH0314924A - Clutch device - Google Patents

Abstract

PURPOSE:To always enable constant changeover of transmission torque by engaging an engaging element with a portion between a casing and a first shaft while utilizing twist of a torsional bar, and switching a rotational torque between the first shaft and the casing. CONSTITUTION:When front wheels are slipped and the rotation of a first shaft 4 is faster than that of a casing 1, the rotational difference is generated between a second shaft 2 and the casing 1. Then, difference is generated in movement of viscous material on a bottom side of an inner port 3 of a pressurized plate side. Shearing resistance is caused inside a viscous layer 20 to apply force which is stopping the rotation of a pressurized plate 14 and the shaft 7. The shaft 7 is slipping to the shaft 4, and a torsional bar 9 is twisted. When the rotation of the casing 1 is agreed with that of the shaft 4, the torsional bar 9 is twisted back, and force resetting to the original condition is generated against the shearing resistance of the viscous layer 20. An engagement element 30 is pressed in a circumferential direction by means of contact to a cylindrical surface 22, a clutch is disconnected, and the casing 1 is rotated independent on the shaft 4.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a Krasochi device that switches a rotation transmission path in accordance with a rotation difference between a human power side and an output side.

[Conventional technology]

In 4-wheel drive vehicles, which normally drive two wheels and perform four-wheel drive by transmitting the driving force to the other two wheels when there is a difference in rotation speed between the front and rear axles, the drive shaft and differential A viscous cassock spring is used between the two to switch the rotational transmission path according to the rotational difference between the two.

This viscous coupling has a large number of plates connected to the human power shaft and the housing inside the housing, and a highly viscous material such as silicone oil! The transmission of rotational torque is switched between the housing and the input shaft by utilizing the shear force generated when a highly viscous material is sheared by the mutual rotation of the plates. ing.

[Problem to be solved by the invention]

However, in the viscous coupling that utilizes the shear force of a highly viscous substance as described above, the shear resistance of the highly viscous substance increases at low rotation speeds, and the amount of transmitted torque increases. For this reason, a structure in which a viscous coupling is installed instead of a center differential has the disadvantage that the braking phenomenon in tight corners cannot be completely eliminated.

Additionally, when the coupling is operated for a long time, the temperature inside the coupling increases due to the agitation resistance of the silicone oil, and this temperature rise causes the silicone oil to expand and increase the internal pressure, causing the transmission of 1~1. It may rise rapidly. This increase in transmitted torque disappears when the rotational speed decreases, and the original torque transmission based on viscous resistance is restored. However, in order to eliminate the above characteristics, the amount and viscosity of the silicone oil to be filled must be adjusted. It has the disadvantage that it needs to be controlled within a strict range, and assembly work is time-consuming.

The present invention has been made in view of the above-mentioned drawbacks, and an object of the present invention is to provide a clutch device that can perform stable torque transmission with a simple structure by mechanically switching the transmission torque.

[Means to solve the problem]

In order to solve the above-mentioned problems, this invention inserts the end of a first shaft into the internal hole of a bottomed cylindrical casing, and a second shaft disposed coaxially with the end of the first shaft. One end is connected via a torsion bar, and the other end of the second shaft is connected to a pressure receiving plate that rotatably fits into the internal hole, and a high viscosity material is connected between the pressure receiving plate and the bottom of the internal hole. forming a layer of material, forming a cam surface on the outer diameter surface of the end of the first shaft, and attaching an engagement sleeve whose inner diameter surface is a cylindrical surface to the inner surface of the inner hole corresponding to the cam surface; A retainer is installed between the cam surface and the cylindrical surface, and an engager is provided in a pocket provided in the retainer and engages with the cylindrical surface and the cam surface through relative rotation of the retainer and the first shaft; Incorporating an elastic member that holds the locking element in a position where it does not engage with the cylindrical surface and the cam surface,
The retainer and the second shaft are connected by pins projecting in the radial direction from the second shaft.

Further, in the above structure, the second shaft and the pressure receiving plate are rotatably provided, and one end of a helical spring wound around the outer diameter of the second shaft is connected to the second shaft, and the other end is connected to the pressure receiving plate. can be adopted.

[Effect]

When the first shaft is connected to the front wheel, which is the drive wheel, and the casing is connected to the rear wheel, the rotation applied to the first shaft is transmitted to the second shaft via the torsion bar, but the casing is connected to the rear wheel. Since it is rotated by the wheels, the driving torque from the first shaft is not transmitted, and it remains separated from the first shaft and rotates together.

Now, when the rotation of the first shaft exceeds the rotation of the casing due to the front wheel's slinop, etc., shear resistance occurs inside the layer of high viscosity material between the second shaft and the casing, and an attempt is made to stop the rotation of the second shaft. A force acts on it. For this reason, there is a deviation in rotation between the first shaft and the second shaft, and the torsion bar connected to both is twisted.When the torsion bar is twisted, the retainer connected to the second shaft is Because it rotates relative to the shaft, the locking element engages the cylindrical surface of the retaining sleeve and the cam surface of the first shaft, and the rotation of the first shaft is transmitted to the casing via the locking element, causing the casing to move in the same direction. Rotate by rotating. When the rotation of the first shaft and the casing become the same, the torsion bar untwists against the shear resistance of the highly viscous material, so the retainer rotates with respect to the first shaft and returns to the neutral position. , the engagement element is disengaged. Therefore, the rotation of the first shaft returns to its original state, and the first shaft is separated from the casing.

Note that power transmission may be configured such that the casing side is the input side and the rotational force is transmitted from the casing to the first shaft via the second shaft. [Example] Hereinafter, an example of the present invention will be described based on the attached drawings. As shown in FIGS. 1 and 2, the casing 1 has a mounting hole 2 formed in one end surface, a cylindrical internal hole 3 formed in the other end surface, and a first The end of the shaft 4 is inserted.

The first shaft 4 is provided with a shaft insertion hole 5 and a through hole 6 on the shaft core, and a second shaft 7 is inserted into the shaft insertion hole 5 and rotatably supported.

A torsion bar insertion hole 8 is provided at the tip of the second shaft 7 that fits into the shaft insertion hole 5 in alignment with the shaft center.
In this torsion bar insertion hole 8 and the through hole 6 of the first shaft 4,
A toshigon bar 9 is rotatably inserted. Both ends of the torsion bar 9 are penetrated by locking dowels 10, 1) inserted in the radial direction into the first shaft 4 and the second shaft 7, respectively. is connected to the first shaft 4 and the second shaft 7 so as to rotate together.

In addition, a square shaft 12 is formed on the tip surface of the second shaft 7, and the first shaft
The square shaft 12 is located at the end surface of the shaft insertion hole 5 in the shaft 4.
A square hole 13 is provided for fitting, and normally the square hole 1
3 and the square shaft 12 is provided with a rotational clearance.

A pressure receiving plate 1 movably fitted into an internal hole 3 of the casing 1 is attached to the rear end of the second shaft 7 facing toward the back of the casing 1.
4 through the central hole 14a.

A radial pin 16 that engages with a radial groove 15 provided along the central hole 14a is inserted into the end of the second shaft 7, and the second shaft 7 and the pressure receiving plate 14 are connected in the rotational direction. are connected so that they move as one. Further, the pressure receiving plate 14 is placed between the pressure receiving plate 14 and the end of the first shaft 4 on the bottom surface 3 of the internal hole 3.
A coil spring 17 is provided that presses the pressure plate 14, so that the rotational torque of the second shaft 7 is applied to the pressure receiving plate 14.

The pressure receiving plate 14 is rotatably fitted to the second shaft 7 and the circumferential surface of the internal hole 3 via seal rings 18 and 19 fitted to the inner and outer circumferential surfaces, and the end surface of the pressure receiving plate 14 and A viscous layer 20 filled with a highly viscous substance is formed in the gap between the inner hole 3 and the bottom surface 3a. Silicone oil, silicone putty, etc. can be used as the above-mentioned high viscosity substance.

On the other hand, a retaining sleeve 23 whose inner diameter surface is a cylindrical surface 22 is fitted into the opening side of the internal hole 3 via a cushioning material 21, and both ends of the cylindrical surface 22 are connected to a pair of bearings 24,
24, it is rotatably supported on the outer circumferential surface of the first shaft 4. Further, a cam surface 25 forming a wedge-shaped space between the cylindrical surface 22 and the cylindrical surface 22 is formed on the outer diameter surface of the first shaft 4 corresponding to the cylindrical surface 22 .

Further, a bottle insertion hole 26 is provided on the circumference of the shaft insertion hole 5 of the first shaft 4.
A pin 27 is provided at the end of the second shaft 7 located in the shaft insertion hole 5, and is provided with a pin 27 that extends in the radial direction and loosely fits into the bottle insertion hole 26. A retainer 28 is connected to the retainer 28 .

The retainer 28 is provided with a pocket 29 at a position facing the cam surface 25, and an engager 30 consisting of a roller and an elastic member 31 are incorporated inside the pocket 29. The above-mentioned engaging element 30 is normally held at a neutral position where it does not engage with the cylindrical surface 22 and the cam surface 25 by the elasticity of the elastic member 31.

The elastic member 31, as shown in FIG.
A pair of side plates 31b are provided at both ends of the side plate 31b, and both end members of the side plates 31b are bent outward to form a pair of elastic pieces (not shown).
The peripheral surface of the engaging element 30 is pressed by a pair of side plates 31b facing inside the bracket 29.

This embodiment has the structure as described above.Next, the action of the clutch device of the embodiment will be explained below.
A case where the present invention is applied to a four-wheel drive vehicle that changes to wheels will be explained. In this case, the flange 32 attached to the first shaft 4 is connected to the drive shaft connected to the front wheel, and the casing 1
A differential gear connected to the rear wheels is connected to the mounting hole 2 on the rear end surface of the output side.

Now, when the flange 32 receives rotational torque from the drive shaft, the first shaft 4 rotates, but at this time, the casing 1
Since the torsion bar 9 rotates with the rear wheel at the same rotation speed, no shear resistance is generated in the viscous layer 20, and the torsion bar 9 is not twisted. Therefore, the locking element 30 is at a neutral position between the cylindrical surface 22 and the cam surface 25, and there is no torque transmission through the engaging element 30, so the casing 1 can be freely hung around by the rear wheel, allowing tight corners. No braking phenomenon occurs.

Now, when the front wheel becomes sloppy and the rotation of the first shaft 4 becomes higher than the rotation of the casing 1, a rotation difference occurs between the second shaft 7 and the casing 1, and in the viscous layer 20, the rotation of the pressure plate 14 side increases. Viscous substance and viscosity on the bottom side of internal hole 3! There is a difference in the movement of fJ quality. Therefore, shear resistance occurs inside the viscous layer 20, and a force acts to stop the rotation of the pressure receiving plate 14 and the second shaft 7.

As a result, the second axis 7 tends to deviate from the first axis 4,
Torsion bar 9 is returned by 1.

For the retainer 28, the torsion bar 9 being twisted in this way is the same as being twisted by the second shaft 7 in the opposite direction to the rotational direction of the first shaft 4. The relative movement with respect to the first shaft 4 causes the retainer 28 to rotate.

This movement of the retainer 28 pushes the engaging element 30 and engages the cylindrical surface 22 and the cam surface 25, so that the clasp is raised. Therefore, the rotation of the first shaft 4 is transmitted to the casing 1 via the engager 30, and the casing 1 rotates at the same rotation as the first shaft 4.

On the other hand, when the rotation of the casing 1 becomes the same as the rotation of the first shaft 4, the twisting of the torsion bar 9 disappears, so the second
The shaft 7 responds to the untwisting of the torsion bar 9 and attempts to return to its original state against the shear resistance of the viscous layer. For this reason, the engaging element 30 is pushed in the circumferential direction due to contact with the cylindrical surface 22 and the clutch is cut, and the casing 1 rotates in a state where it is separated from the first shaft 4 by four. However, at the next moment, the rotation of the first shaft 4 becomes higher than the rotation of the casing 1, so the torsion bar S is returned by 1 again and the clutch is engaged in the same manner as above, and the first shaft 4 and the casing 1 are integrated. Rotate.

The above operation is repeated while the front wheels are running on a road surface with low friction, and two-wheel drive becomes four-wheel drive for each front wheel drive, resulting in stable driving. When the slithop stops forming and the shear resistance inside the highly viscous substance disappears, the vehicle becomes two-wheel drive with only the front wheels.

3 and 4 show a second embodiment of the invention.

In this embodiment, the cam surface 25 of the first shaft 4 is a cylindrical surface,
Two retainers 33 and 34 with different diameters are assembled between the cam surface 25 and the cylindrical surface 22 of the engagement sleeve 23, and the retainer 33 on the small diameter side is fixed to the first shaft 4, and the retainer 33 on the large diameter side is fixed to the first shaft 4. The retainer 34 is connected to the second shaft 7 by a pin 27.

In addition, pockets 3 are provided in both retainers 33 and 34, respectively.
5 and 36, and an elastic member 39 and a slug 38 as a locking element whose outer diameter side and inner diameter side are shaped like arcuate surfaces 37 are inserted into the pockets 35 and 36. Both end surfaces of the sprag 38 are pushed by the elasticity of the elastic member 3S, and the arcuate surface 37 is held in a neutral state in which it does not engage with the cylindrical surface 22 and the cam surface 25. Further, when the torsion harness 9 is twisted and the first shaft 4 and the second shaft 7 are rotated, and the large diameter retainer 34 and the small diameter retainer 33 are rotated relative to each other, the sprag 38 is tilted and the arcuate surface 37 is rotated. engages with the cylindrical surface 22 and the cam surface 25, causing the first shaft 4 and the caning to rotate together.

In addition, in the second embodiment, the second shaft 7 and the pressure receiving plate 14
and are fixed by screwing, and the receiving pressure {reverse 14 and the first shaft 4
A disc spring 40 is used instead of a coil spring to be installed in between.

In both the first and second embodiments, the engager 30 or the sublug 38 engages with the cylindrical surface 22 and the cam surface 25 due to the relative rotation of the first shaft 4 and the second shaft 7. , the first shaft 4 and the casing 1 are connected by their engagement.

On the other hand, when relative rotation occurs due to an impact force, the square hole 13 and the square shaft 12 engage, and the rotation of the first shaft 4 is transferred to the second shaft 7.
This prevents damage caused by excessive twisting of the torsion bar.

On the other hand, FIG. 5 shows a third embodiment.

The basic structure of this embodiment is the same as that of the first embodiment, but there is a difference in the connection structure between the second shaft 7 and the pressure receiving plate 41.

That is, the pressure receiving plate 41 is formed into a cap shape, and the end of the second shaft 7 is inserted into the inside of the pressure receiving plate 41, so that both can freely rotate.

Further, one end of a helical spring 42 wound around the outer periphery of the second shaft 7 is fixed to the second shaft 7, and the other end is fixed to the pressure receiving plate 41.

In the above structure, when a rotation difference occurs between the first shaft 4 and the casing 1, the second shaft 7 does not immediately receive shear resistance from the viscous layer 20, but the second shaft 7 rotates and forms a spiral shape. spring 4
2 is wound up, and at the point when the spring 42 is wound up, the second shaft 7 rotates integrally with the pressure receiving plate 41 and receives rotational resistance. In this case, the torsion bar 9 is twisted, the engager 30 rotates relative to the first shaft 4, the clutch is engaged, and the first shaft 4 and the casing 1 rotate together.

On the other hand, in the above clutch state, the first shaft 4 and the casing 1
Even if the rotation difference disappears, it will not break immediately. That is,
Even if the reflection of the torsion bar 9 returns due to the spring resistance of the wound helical spring 42 and the surface pressure between the cam surface 25, the engager 31, and the cylindrical surface 22, the engager 31 remains engaged. The clutch does not move immediately from the position, but when the helical spring 42 is unwound and the resistance force disappears, the elastic member 31 returns the engager 31 to the neutral position, thereby disengaging the clutch. .

In this way, by changing the spring constant of the helical spring 42 and changing the force relationship between the spring force and the torsional torque of the torsion bar S, it is possible to adjust the time during which the cradles are engaged. Therefore, for example, it is possible to automatically cut off the cent after the Kura Nochi is maintained for a certain period of time.

〔Effect of the invention〕

As explained above, the Kurasochi device of the present invention utilizes the tearing of the torsion bar to engage the engager between the casing and the first shaft, thereby transferring rotational torque between the first shaft and the casing. Since the transmission torque is mechanically switched between the two, stable switching of the transmitted torque is possible at all times, and the instability of operation that occurs with viscous couplings can be eliminated.

Furthermore, since the number of parts is smaller than that of a viscous coupling, assembly is easy and a compact transmission device can be provided.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional front view showing a first embodiment of this invention;
Figure 2 is a cross-sectional view taken along line 1'' in Figure 1, and Figure 3 is a cross-sectional view along line 1'' in Figure 1.
A vertical sectional front view showing the embodiment, FIG. 4 is the IV-TV shown in FIG. 3.
A sectional view taken along the line, and FIG. 5 is a longitudinal sectional front view showing the third embodiment. 1... Casing, 3... Internal hole, 4... First shaft, 5... Shaft insertion hole, 7... Second Shaft, S...Torsion shear 14...Pressure plate, 16...
... Pin, 20 ... Viscous layer, 22 ...
...Cylindrical surface, 23...Engagement sleeve, 25.
...Cam surface, 27...Pin,
28...Holding 2L29...Pokenote, 31...Elastic member, 35, 36...Boke 38...Subrag, 41... ...Pressure plate, 30...Engager, 33, 34...Retainer, mount, 39...Elastic member, 42...Spiral spring .

Claims (2)

[Claims] (1) Insert the end of the first shaft into the inner hole of the bottomed cylindrical casing, and connect one end of the second shaft arranged on the same axis to the end of the first shaft via a torsion bar. And the second
A pressure receiving plate rotatably fitted into the internal hole is connected to the other end of the shaft, and a layer of a highly viscous substance is formed between the pressure receiving plate and the bottom surface of the internal hole, and the end of the first shaft is connected to the other end of the shaft. A cam surface is formed on the outer diameter surface, an engagement sleeve whose inner diameter surface is a cylindrical surface is attached to the inner surface of the internal hole corresponding to the cam surface, and a retainer is installed between the cam surface and the cylindrical surface. , an engager that engages with the cylindrical surface and the cam surface due to relative rotation between the retainer and the first shaft, and a position where the engager does not engage with the cylindrical surface and the cam surface, in a pocket provided in the retainer; A clutch device in which the retainer and a second shaft are connected by a pin protruding radially from the second shaft. (2) Claim (1) wherein the second shaft and the pressure receiving plate are rotatably provided, and one end of a helical spring wound around the outer diameter of the second shaft is connected to the second shaft and the other end is connected to the pressure receiving plate. The clutch device described in .