JP3027806B2 - Driving force transmission device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a driving force transmitting device disposed between rotating shafts, such as between a driving shaft and a driven shaft of a vehicle, for transmitting torque between the two rotating shafts.

[0002]

2. Description of the Related Art As one type of a driving force transmission device, "Electromagnetic multi-plate clutch" is disclosed in Japanese Utility Model Registration No. 2525611.
And a main clutch including a main clutch disposed between the inner and outer rotating members coaxially and relatively rotatable with each other, and operated by energization to frictionally engage the main clutch. There is a driving force transmission device of a type that includes an electromagnetic pilot clutch mechanism for causing the two rotating members to be in a connected state capable of transmitting torque by the frictional engagement force of the main clutch. The pilot clutch mechanism includes an electromagnet, an armature, It is composed of a plate clutch.

In the driving force transmission device, the outer rotating member is formed of a steel front housing made of a magnetic material and a stainless steel rear housing made of a non-magnetic material in order to operate the pilot clutch mechanism well. The two housings are integrated by welding.

The driving force transmission device is mounted as a center differential of a four-wheel drive vehicle, and energizes an electromagnet constituting a pilot clutch mechanism to attract an armature and frictionally engage a multi-plate clutch.
Amplifying the frictional engagement force of the multi-plate clutch with the cam mechanism and transmitting it to the main clutch, and transmitting the torque between the front and rear wheels by frictionally engaging the main clutch, thereby limiting the differential between the front and rear wheels. It is.

[0005]

By the way, in a four-wheel drive vehicle equipped with a driving force transmission device of the type described above,
When the vehicle is towed while the front wheel is lifted, a considerable differential rotation occurs between the floating front wheel and the grounded rear wheel, and this state lasts for a long time. For this reason, in the pilot clutch mechanism, a drag torque is generated due to the viscosity of the lubricating oil and the main clutch is frictionally engaged despite the non-energized state. As a result, the frictional engagement of the main clutch is maintained for a long time to generate heat, and the temperature of the main clutch becomes high.

When the temperature of the main clutch becomes high, the amount of thermal expansion of the main clutch becomes larger than the amount of thermal expansion of the housing as the outer rotating member, and the difference in the amount of thermal expansion increases the frictional engagement force of the main clutch. As a result, the temperature of the main clutch further rises and thermally expands, and a compressive force acts between the inner clutch plate and the outer clutch plate constituting the main clutch, so that a so-called hump state occurs.

If the hump state continues, the difference in the amount of thermal expansion between the main clutch and the housing exceeds the allowable amount of elastic deformation due to the rigidity of each component constituting the apparatus.
The main clutch will maintain an abnormal friction engagement state, and will be in an abnormal heating state and will be worn and damaged.

In order to cope with this, means for setting a large clearance between the clutch plates of the main clutch can be considered. However, if such means is employed, the play between the main clutch and the pilot clutch mechanism, for example, the pilot clutch mechanism The play in the cam mechanism for transmitting the frictional engagement force to the main clutch is increased, and the responsiveness of torque transmission during normal running of the four-wheel drive vehicle is reduced.

Therefore, an object of the present invention is to reduce the responsiveness of torque transmission during normal running of a vehicle,
It is to address the above-mentioned problem.

[0010]

SUMMARY OF THE INVENTION The present invention relates to a driving force transmitting device, and more particularly to an outer rotating member between an inner rotating member and an outer rotating member which are coaxially and relatively rotatable with each other.
A main clutch positioned on one side wall and supported by the same side wall, and the other side of the outer rotating member between the two rotating members.
An electromagnetic type pilot clutch mechanism for frictionally engaging and operated by situated on the wall side energizing said at between the two rotary members
Position between the main clutch and the pilot clutch mechanism
At above includes a cam mechanism for the pressing to the main clutch into friction engagement with the main clutch to the one side wall side of the outer rotating member in response to the frictional engagement force of the pilot clutch mechanism, the friction engagement force of the main clutch The present invention relates to a driving force transmission device that brings the two rotating members into a connected state capable of transmitting torque.

According to the present invention, there is provided a driving force transmitting apparatus of the above-mentioned type, wherein the outer rotating member is formed of a material having a large thermal expansion. It can be formed of a material having a large expansion and a small rigidity.

In the driving force transmission device according to the present invention,
Wherein the outer rotary member, constituted by a rear housing for covering a tubular front housing having a back wall, a rear end opening of the front housing, the front maggots
A rear wall of the outer rotating member is formed on one side wall of the outer rotating member, and the rear housing is formed on another side wall of the outer rotating member.
And at least the front housing of the outer rotating member can be formed of an aluminum alloy, and at least the front housing of the outer rotating member is formed of an aluminum alloy, and each clutch plate of the main clutch can be formed. Can be formed of iron. this
In this case, the inner clutch
Rate or outer clutch plate
The surface may be provided with a friction material. Also,
The cam mechanism is supported on another side wall of the outer rotating member.
Configuration.

Further, the present invention provides a driving force transmission of the following type:
The device can be applied. That is, the back wall
Cylindrical front housing and front housing
Out of a rear housing that covers the opening at the other end of the
Coaxial and relative rotation inside the case and the outer case
Between the inner shafts where possible
Maink located on the back wall of the jing and supported by the back wall
Latch, between the outer case and the inner shaft
Is located on the rear housing side to operate by
An electromagnetic pilot clutch mechanism for frictional engagement;
Between the outer case and the inner shaft
Between the clutch and the pilot clutch mechanism.
Of the pilot clutch mechanism
The main clutch is moved to the front according to the frictional engagement force.
Pressing against the back wall of the housing to rub the main clutch
A cam mechanism for engaging the main clutch;
The outer case and the inner shaft are
A drive force transmission device that is in a connected state capable of transmitting torque
And move the cam mechanism to the pilot clutch mechanism side.
Is located on the rear housing and is
Integrated with the outer case by frictional engagement of clutch mechanism
And a first cam member rotating toward the main clutch.
Second cam portion which is placed and rotates integrally with the inner shaft
And a member interposed between the first cam member and the second cam member.
The second cam member is rotated by the relative rotation of these two cam members.
To the main clutch side to move the main clutch
Type that consists of a cam follower that presses
The power transmission device can be applied. in this case
The front housing is made of a material having a large thermal expansion.
Formed, the front housing is made of aluminum alloy
And the rear housing is formed of iron.
Can be achieved.

[0014]

In the vehicle equipped with the driving force transmission device having the above-described configuration, the pilot clutch mechanism constituting the driving force transmission device is energized to actuate the pilot mechanism to frictionally engage the main clutch. With the frictional engagement force of the main clutch, the two rotating members can be brought into a connected state in which torque can be transmitted, whereby the vehicle can be brought into a four-wheel drive state.

Further, in the vehicle, when the vehicle is towed, the front wheels are towed while being floated, so that a considerable differential rotation occurs between the floating front wheels and the grounded rear wheels, and this state is prolonged. Lasts for hours. Therefore, in the pilot clutch mechanism, a drag torque is generated due to the viscosity of the lubricating oil, so that the main clutch is frictionally engaged, and the temperature of the main clutch is raised. Such a state is the same as that of a vehicle equipped with a conventional driving force transmission device.

Thus, in the driving force transmission device according to the present invention, the outer rotating member is formed of a material having a larger thermal expansion than that of the conventional rotating member formed of iron. For this reason, the outer rotating member has a large thermal expansion amount despite the low temperature of the main clutch, has a small frictional engagement action with the main clutch, and greatly delays the time during which the main clutch is in the hump state.

Further, in the driving force transmission device according to the present invention, the outer rotating member can be formed of a material having a large thermal expansion and a small rigidity as compared with a conventional member formed of iron. In this case, even when the wrecker travel time of the vehicle is long and the main clutch reaches a hump state before arriving at the repair shop, the outer rotating member has a lower rigidity and elasticity compared to the conventional one formed of iron. Since it is easy to deform and has a relatively large thermal expansion amount, it is possible to suppress excessive frictional engagement of the main clutch, and it is possible to suppress an abnormal heating state of the main clutch and, consequently, the device. Thereby, wear and damage of the main clutch can be prevented.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to the drawings. FIG. 1 shows an example of a driving force transmission device according to the present invention. As shown in FIG. 3, the driving force transmission device 10 is disposed on a driving force transmission path to a rear wheel side of a four-wheel drive vehicle.

In the four-wheel drive vehicle, the transaxle 21 integrally includes a transmission, a transfer, and a front differential, and outputs the driving force of the engine 22 to both axle shafts 23 a via the transaxle 21. Then, the left and right front wheels 23b are driven and output to the propeller shaft 24 side. The propeller shaft 24 is connected to the rear differential 25 via the driving force transmission device 10, and the propeller shaft 24 and the rear differential 2
When the transmission 5 is connected to transmit torque, the driving force is transmitted to the rear differential 25, and is output from the differential 25 to both axle shafts 26a to drive the left and right rear wheels 26b.

The driving force transmission device 10 is accommodated in a differential carrier 27 together with a rear differential 25 and is supported by the carrier 27. The driving force transmission device 10 is supported by the vehicle body via the carrier 27. FIG.
Shows a half portion obtained by cutting the driving force transmission device 10 about the axis, and a half portion (not shown) is omitted because it is formed substantially symmetrically about the axis.

As shown in FIG. 1, the driving force transmitting device 10 includes an outer case 10a as an outer rotating member,
It has an inner shaft 10b, a main clutch 10c, a pilot clutch mechanism 10d, and a cam mechanism 10e, which are inner rotating members.

The outer case 10a comprises a front housing 11a having a bottomed cylindrical shape, and a rear housing 11b screwed into a rear end opening of the front housing 11a to cover the opening.
Is formed of an aluminum alloy which is a non-magnetic material, and the rear housing 11b is formed of iron which is a magnetic material. A stainless steel cylinder 11b1, which is a nonmagnetic material, is embedded in a radially intermediate portion of the rear housing 11b, and the cylinder 11b1 forms an annular nonmagnetic portion.

A nut member 11c is screwed on the screw portion formed on the outer periphery of the rear end of the rear housing 11b so as to be able to advance and retreat. The nut member 11c tightens the front housing 11a from the rear end side, and presses the threaded portion of the front housing 11a against the threaded portion of the rear housing 11b to eliminate play between these threaded portions.

The outer case 10a is rotatably supported by a differential carrier 27 at the outer periphery of the front end of the front housing 11a, and is supported by the differential carrier 27 at the outer periphery of the rear end of the rear housing 11b. . A rear end of the propeller shaft 24 is connected to a front end of the front housing 11a so as to transmit torque.

The inner shaft 10b is inserted into the front housing 11a through a central portion of the rear housing 11b in a liquid-tight manner, and is restricted from moving in the axial direction.
b is rotatably supported. Inner shaft 10b
, The tip of the drive pinion shaft 28 is inserted and connected to transmit torque.

The main clutch 10c is a wet type multi-plate type friction clutch, and includes a large number of clutch plates (an inner clutch plate 12a, an outer clutch plate 12a).
b), and is disposed on the back wall side of the front housing 11a. Each inner clutch plate 12a constituting the friction clutch is spline-fitted to the outer periphery of the inner shaft 10b and is mounted so as to be movable in the axial direction.
Further, each outer clutch plate 12b is spline-fitted to the inner periphery of the front housing 11a and is mounted so as to be movable in the axial direction. The respective inner clutch plates 12a and the respective outer clutch plates 12b are alternately positioned, abut against each other and frictionally engage with each other, and are separated from each other to be in a free state.

The pilot clutch mechanism 10d includes an electromagnet 13, a wet multi-plate friction clutch 14, and an armature 15. The electromagnet 13 has an annular shape, and is fitted to the yoke 16 so that the rear housing 1
1b is fitted in the annular recess 11b2. Yoke 16
Is supported by a differential carrier 27 via a conical spring 16a in a state of being axially supported, and is rotatably supported on the outer periphery of the rear end of the rear housing 11b. Thereby, the rear housing 11
A predetermined air gap is formed between b and the yoke 16.

The friction clutch 14 includes a plurality of clutch plates (an inner clutch plate 14a and an outer clutch plate 14b). Each inner clutch plate 14a has an outer periphery of a first cam member 17 constituting a cam mechanism 10e described later. The outer clutch plates 14b are spline-fitted to the inner periphery of the front housing 11a and are movably mounted in the axial direction. Each of the inner clutch plates 14a and each of the outer clutch plates 14b are alternately positioned, abut against each other and frictionally engage with each other, and are separated from each other to be in a free state.

In the pilot clutch mechanism 10d, the yoke 1 is turned on by energizing the electromagnetic coil of the electromagnet 13.
6, rear housing 11b, friction clutch 14, armature 15, friction clutch 14, rear housing 11b,
A magnetic path is formed between the yoke 16 and the magnetic path. The power supply to the electromagnetic coil of the electromagnet 13 is turned on and off by turning on and off the switch. The switch is provided near the driver's seat in the vehicle compartment so that the driver can easily operate the switch. Has become. Note that the switch may be omitted if the driving force transmission device is configured only in a second driving mode described later.

The cam mechanism 10e includes a first cam member 17, a second cam member 18, and a cam follower 19. In the first cam member 17 and the second cam member 18, a plurality of cam grooves opposing each other are formed on the opposing surfaces at predetermined intervals in the circumferential direction. The first cam member 17 is
It is rotatably fitted to the outer periphery of the inner shaft 10b,
The inner clutch plate 14a of the friction clutch 14 is spline-fitted to the outer periphery of the rear housing 11b.

The second cam member 18 is connected to the inner shaft 10.
The main clutch 10c is spline-fitted to the outer periphery of the main clutch 10b so as to be integrally rotatable, and is opposed to the inner clutch plate 12a of the main clutch 10c. This second cam member 1
A ball-shaped cam follower 19 is interposed between the cam grooves 8 and the first cam member 17 facing each other.

Thus, in the driving force transmission device 10, the outer case 10a corresponds to the outer rotating member of the present invention, and the outer case 10a is composed of an aluminum alloy front housing 11a and an iron rear housing 11a.
b. On the other hand, the main clutch 10
c is, as shown in FIG. 2, a number of inner plates 12a.
And an outer plate 12b. The inner plate 12a has a friction member 1 made of paper on the surface of an iron core 12a1.
2a2, and the outer plate 12
b is made of iron. The clutch chamber in which the main clutch 10c is disposed and the clutch chamber in which the friction clutch 14 of the pilot clutch mechanism 10d is disposed are filled with lubricating oil.

In the driving force transmission device 10 having such a configuration, the electromagnet 1 constituting the pilot clutch mechanism 10d is used.
When the power is not supplied to the third electromagnetic coil, no magnetic path is formed, and the friction clutch 14 is in the non-engaged state.
Therefore, the pilot clutch mechanism 10d is in a non-operating state, and the first cam member 1 constituting the cam mechanism 10e is not operated.
7 is rotatable integrally with the second cam member 18 via the cam follower 19, and the main clutch 10c is in a non-operating state. Therefore, the vehicle constitutes the first drive mode of the two-wheel drive.

On the other hand, when the electromagnetic coil of the electromagnet 13 is energized, a magnetic path is formed in the pilot clutch mechanism 10 d, and the electromagnet 13 attracts the armature 15. For this reason, the armature 15 presses the friction clutch 14 to cause frictional engagement, connects the first cam member 17 of the cam mechanism 10e to the front housing 11a side, and
And a relative rotation is generated between them. As a result, the cam mechanism 1
0e, the cam followers 19 move the two cam members 17, 18
Are pressed away from each other.

As a result, the second cam member 18 is pressed toward the main clutch 10c to cause the main clutch 10c to frictionally engage in accordance with the frictional engagement force of the friction clutch 14, thereby transmitting torque between the outer housing 10a and the inner shaft 10b. I do. Thus, the vehicle constitutes a continuously variable four-wheel drive second drive mode in which the propeller shaft 24 and the drive pinion shaft 28 are in a non-coupled state to a directly coupled state. In this driving mode, the driving force distribution ratio between the front and rear wheels is 100: 0 (two-wheel driving state) to 50:
It can be controlled in the range of 50 (directly connected four-wheel drive state).

When the current applied to the electromagnetic coil of the electromagnet 13 is increased to a predetermined value, the armature 15
, The armature 15 is strongly sucked, the frictional engagement force of the friction clutch 14 is increased, and the relative rotation between the cam members 17 and 18 is increased. As a result,
The cam follower 19 increases the pressing force on the second cam member 18 to bring the main clutch 10c into a connected state. For this reason, the vehicle constitutes a third drive mode of four-wheel drive in which the propeller shaft 24 and the drive pinion shaft 28 are directly connected.

When the vehicle is towed, the front wheel 23b is towed while being lifted. Therefore, the rear wheel 26b which rotates while contacting with the floating front wheel 23b is grounded.
And a considerably large differential rotation is generated, and this state is maintained for a long time. Therefore, the pilot clutch mechanism 10
In the friction clutch 14 that constitutes d, a drag torque is generated due to the viscosity of the lubricating oil, the main clutch 10c is frictionally engaged, and the temperature of the main clutch 10c is increased, despite the non-energized state. Such a state is the same as that of a vehicle equipped with a conventional driving force transmission device.

However, in the driving force transmission device 10, the front housing 11a constituting the outer case 10a is formed of an aluminum alloy, and has a larger thermal expansion amount than that of the conventional case formed of iron. And the rigidity is set small. For this reason, the front housing 11
a is that the amount of thermal expansion is large even though the temperature is low with respect to the main clutch 10c, the influence on the frictional engagement of the main clutch 10c is small, and the time during which the hump state occurs in the main clutch 10c is greatly delayed. Can be.

Also, even if the main clutch 10c is in a hump state before the vehicle arrives at the repair shop due to the long tow travel time of the vehicle, the rigidity of the front housing 11a is smaller than that of a conventional iron. The main clutch 10c is easily deformed elastically and has a relatively large amount of thermal expansion.
Since the friction material 12a2 adhered to the surface of the first clutch 1 is easily elastically deformed, excessive frictional engagement of the main clutch 10c can be suppressed, and an abnormal heating state of the main clutch 10c and, consequently, the driving force transmission device. This can prevent wear and damage of the main clutch 10c.

FIG. 4 shows a main clutch 10c and a front housing 11a constituting the driving force transmission device 10.
3 is graphs a, b, and c showing the relationship between the temperature and the amount of thermal expansion. Here, the graph a shows the pilot clutch mechanism 10d.
The graph b shows the relationship in the front housing made of an aluminum alloy, and the graph c shows the relationship in the front housing made of an iron, in which drag torque is generated.

Referring to the graph of FIG. 4, the thermal expansion of the front housing is larger in the aluminum alloy front housing than in the iron front housing in all temperature ranges, and the thermal expansion of the main clutch 10c is larger than that of the iron front housing. Due to the characteristics of the friction material 12a2, it is smaller than each front housing at a low temperature, becomes larger than the iron front housing when a predetermined temperature (low temperature side) is reached by frictional engagement, and further at a predetermined temperature (high temperature side). When it reaches, it becomes larger than the aluminum alloy front housing.

In this case, since the aluminum alloy front housing is easily elastically deformed, excessive frictional engagement of the main clutch 10c can be suppressed, and the main clutch 10c and, consequently, the driving force transmitting device in an abnormally heated state. This can prevent wear and damage of the main clutch 10c.

FIG. 5 is a graph showing the relationship between time and temperature and the relationship between time and torque in a driving force transmission device in which the housing 11a is made of an aluminum alloy or iron. In these graphs, graphs a1 and b1 correspond to housing 1
Relationship between time and temperature when 1a is an aluminum alloy (a
1) and the relationship between time and torque (b1). Graphs a2 and b2 show the relationship between time and temperature (a2) and the relationship between time and torque (b2) when the housing 11a is iron. Referring to these graphs, it can be seen that when the housing 11a is made of an aluminum alloy, the temperature and the torque increase with time are lower than when the housing 11a is made of iron.

Since the front housing 11a of the driving force transmission device 10 is formed of an aluminum alloy, the weight is significantly reduced as compared with a conventional driving force transmission device employing an iron front housing. And leakage of magnetic flux to the front housing 11a when the electromagnet 13 of the pilot clutch mechanism 10d is energized can be accurately prevented.

In the driving force transmission device 10, since the front housing 11a is formed only of an aluminum alloy which is a non-magnetic material, in order to prevent magnetic flux leakage, a part of iron is made of stainless steel or the like. The cost can be reduced as compared with the conventional driving force transmission device employing the constituent front housing.

Further, in the driving force transmission device 10, as an inner plate of the main clutch 10c, an inner plate 12a in which a friction material 12a2 made of paper is adhered to the surface of an iron core 12a1 is employed to prevent judder. Although an improvement in performance has been achieved, an inner plate consisting of only an iron core may be employed. In this case, although the rigidity of the main clutch increases and the amount of elastic deformation decreases, the thermal expansion at a high temperature is smaller than that obtained by attaching the friction material 12a2. It is possible to obtain the same effect as that provided by the method.

[Brief description of the drawings]

FIG. 1 is a partial sectional view showing a driving force transmission device according to an example of the present invention.

FIG. 2 is a partial cross-sectional view showing a main clutch constituting the driving force transmission device.

FIG. 3 is a skeleton diagram of a vehicle equipped with the driving force transmission device.

FIG. 4 is a graph showing a relationship between a temperature of a main clutch and a front housing and a thermal expansion amount.

FIG. 5 is a graph showing a relationship between time and temperature and a relationship between time and torque in a driving force transmission device whose housing is made of an aluminum alloy or iron.

[Explanation of symbols]

Reference numeral 10: driving force transmission device, 10a: outer case, 10b
... inner shaft, 10c ... main clutch, 10d ...
Pilot clutch mechanism, 10e ... cam mechanism, 11a ...
Front housing, 11b ... Rear housing, 11b
1 ... cylindrical body, 11b2 ... annular recess, 11c ... nut member, 1
2a: inner clutch plate, 12a1: core, 12
a2: friction material, 12b: outer clutch plate, 13
... Electromagnet, 14 ... Main clutch, 14a ... Inner clutch plate, 14b ... Outer clutch plate, 15
... armature, 16 ... yoke, 16a ... conical spring, 17 ... first cam member, 18 ... second cam member, 19
... Cam follower, 21 ... Trans axle, 22 ... Engine, 23a ... Axle shaft, 23b ... Front wheel, 2
4 ... Propeller shaft, 25 ... Rear differential, 26a ... Axle shaft, 26b ... Rear wheel, 27 ...
Differential carrier, 28 ... drive pinion shaft.

Continued on the front page (72) Inventor Koichi Suzuki 1 Toyota Town, Toyota City, Aichi Prefecture Inside Toyota Motor Corporation (72) Inventor Akihiko Ikeda 1 Toyota Town, Toyota City, Aichi Prefecture Inside Toyota Motor Corporation (56) Reference Document JP-A-6-249258 (JP, A) JP-A-8-247177 (JP, A) JP-A-4-18723 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) F16D 27/10 B60K 17/34

Claims (8)

(57) [Claims] 1. Positions are coaxial and relatively rotatable with each other.
Between the inner rotating member and the outer rotating member,
A main clutch positioned on one side wall and supported by the same side wall, and another side wall of the outer rotating member between the two rotating members.
And a pilot clutch mechanism of an electromagnetic type which is actuated by energization and is frictionally engaged with the rotating member.
Located between the in-clutch and the pilot clutch mechanism.
Comprising a cam mechanism for frictionally engaging the pressing to the main clutch to the one side wall side of the outer rotating member the main clutch in response to frictional engagement force of the pilot clutch mechanism,
A driving force transmission device for connecting the two rotating members to each other so that torque can be transmitted by frictional engagement of the main clutch, wherein the outer rotating member is formed of a material having a large thermal expansion. . 2. The driving force transmission device according to claim 1, wherein the outer rotating member is formed of a material having low rigidity. 3. The driving force transmission device according to claim 1 , wherein the outer rotating member includes a cylindrical front housing having a back wall and a rear housing that covers a rear end opening of the front housing. A back wall of the front housing is formed on one side wall of the outer rotating member, and the rear housing is
A driving force transmission device formed on another side wall of the rolling member, wherein at least a front housing of the outer rotating member is formed of an aluminum alloy. 4. The driving force transmission device according to claim 1, wherein each clutch plate of the main clutch is formed of iron. 5. The driving force transmitting device according to claim 1, wherein a friction material is provided on one of the surfaces of the inner clutch plate and the outer clutch plate constituting the main clutch. Driving force transmission device. 6. The driving force transmission device according to claim 1,
The cam mechanism is supported on the other side wall of the outer rotating member.
A driving force transmission device characterized in that: 7. A cylindrical front housing having a back wall.
Of the same front housing Rear how to cover the other end opening
Outer case made of jing and inside of the outer case
Between the inner shafts located coaxially and relatively rotatable
On the back wall side of the front housing
The main clutch supported, the outer case and the
It is located on the rear housing side between
An electromagnetic pilot clutch that operates with electricity and frictionally engages
Switch mechanism, between the outer case and the inner shaft.
The main clutch and the pilot clutch mechanism
The pyrometer is supported between the rear housing and
The main clutch according to the frictional engagement force of the
Switch to the back wall side of the front housing to
A cam mechanism for frictionally engaging the in-clutch;
The outer case and the outer case are
Drive to make the inner shaft connected to transmit torque
A force transmission device, wherein the cam mechanism is connected to the pilot
Positioned on the clutch mechanism side and supported by the rear housing
And the frictional engagement of the pilot clutch mechanism
A first cam member that rotates integrally with the outer case;
Position on the clutch side and rotate integrally with the inner shaft.
A second cam member that rotates, the first cam member and the second cam member.
Between the cam members by the relative rotation of these two cam members.
Push the second cam member toward the main clutch to
Composed of a cam follower that presses the main clutch
In the driving force transmission device, the front housing
Characterized in that the ring is made of a material with high thermal expansion
Driving force transmission device. 8. A driving force transmission device according to claim 7, wherein
The front housing constituting the outer case is
Formed of aluminum alloy, and the rear housing is
Driving force transmission device characterized by being formed of iron
Place.