JP2003013978A - Seal structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To protect a rotary side member exposed and arranged to the outside against sliding with a seal. SOLUTION: A coupling 1 exposed and arranged in the vicinity of a stationary member 14, a dust cover 15 installed in q cylindrical member 19 and preventing foreign objects from invading between the coupling 1 and stationary member 14, and a seal 17 in a place opposing to the dust cover 15 on the stationary member 14 are arranged. Further, a seal portion 123 is kept in contact with the dust cover 15.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to, for example, a rotating side member such as a coupling which is exposed on a propeller shaft of a four-wheel drive vehicle and a stationary side member which supports the rotating side member on a vehicle body. The present invention relates to a seal structure used for.

[0002]

2. Description of the Related Art Generally, for example, Japanese Unexamined Patent Publication No. 1-1826.
One in which the rotating side member is exposed to the outside in the vicinity of the stationary side member, such as one in which a coupling (rotating side member) as disclosed in Japanese Patent Publication No. 33 is disposed on the propeller shaft of a four-wheel drive vehicle, is disclosed. Thus, in the case where the rotary side member is exposed to the outside in this way, a seal structure such as a dust cover or a seal member is provided between the rotary side member and the stationary side member, and It is known that foreign matter is prevented from entering the relative rotation part with respect to the rotation side member.

[0003]

However, in the case of the coupling (rotating member) or the like arranged on the propeller shaft of a four-wheel drive vehicle as in the above-mentioned conventional structure, the weight of the entire device is reduced and the rotating member is rotated. There is a demand for forming the housing, which is a rotating member, from an aluminum alloy (light metal) or the like for reasons such as weight reduction and reduction of the moment of inertia.

However, when the housing, which is the rotating member, is made of aluminum alloy (light metal) or the like, there is a problem that the sliding portion with the seal member cannot be set.

Therefore, it is necessary to take measures such as separately providing a color member having excellent wear resistance on the sliding portion. In that case, the manufacturing cost and the component management cost increase with the increase in the number of parts, which results in cost reduction. There is a new problem that is disadvantageous to.

Further, there is also known one in which a dust cover or the like is provided to improve the effect of preventing foreign matter from entering, but conventionally, the dust cover and the seal member are arranged in different places,
Each coupling space is required, so it is difficult to make the entire coupling compact.

Therefore, the present invention has a seal structure provided between the rotating side member and the stationary side member which are exposed to the outside, and the rotating member can be maintained while maintaining high sealing performance without increasing the number of parts. An object of the present invention is to provide a seal structure capable of being made of a lightweight material, reducing the weight of the rotating member, and improving fuel consumption in the case of an in-vehicle device.

[0008]

A seal structure according to a first aspect of the present invention is a seal provided between a stationary member and a rotating member that is exposed to the outside in the vicinity of the stationary member. In the structure, a dust cover that prevents foreign matter from entering between the rotating side member and the stationary side member is provided on the rotating member side, and a sealing member is provided on the stationary side member near the dust cover. Is brought into contact with the dust cover, and the seal member is slid between the dust cover and the dust cover.

As described above, according to the seal structure of claim 1,
By sliding the seal member with the dust cover attached to the rotary member of the rotary member, the rotary member is released from directly sliding on the seal member.

Therefore, even if the rotating member is made of a light metal such as an aluminum alloy, sliding with the seal member and abrasion due to sliding do not occur. Therefore, the rotating member is made of a light metal and the rotating side member is lightweight. It is possible to improve the fuel efficiency of the engine (motor) by reducing the inertia moment.

Further, as described above, since the dust cover is used as the member that slides with the seal member, it is not necessary to use a dedicated member such as a collar in order to improve the wear resistance. It is possible to avoid increase in parts cost, parts management cost, assembly work cost, etc.

Since the seal member is arranged between the dust cover and the stationary member (the dust cover and the seal member are arranged at the same position), the seal member and the dust cover are arranged at different positions. Compared with, the arrangement space is narrower, and the entire rotating side member including the dust cover is made more compact.

The rotating member of the rotating member which is released from sliding with the seal member may be made of a resin such as a light metal such as an aluminum alloy as long as the necessary strength can be obtained. Good.

According to a second aspect of the invention, there is provided the seal structure according to the first aspect, wherein the rotation side member is a clutch arranged between the case-shaped torque transmitting member and the shaft-shaped torque transmitting member. It is an electromagnetic clutch that is discontinuous by an electromagnet, and is characterized in that the dust cover is attached to the case-shaped torque transmission member, and it is possible to obtain the same operation and effect as the configuration of claim 1.

The case-shaped torque transmitting member of the electromagnetic clutch (rotating member) which is intermittently operated by the electromagnet is made of a non-magnetic material such as an aluminum alloy or austenitic stainless steel to prevent leakage of magnetic flux and to mount on-vehicle device. In order to reduce the loss of the battery, which is the power source of the electromagnet, to improve the fuel efficiency of the prime mover, the case-shaped torque transmission is improved by attaching the dust cover to the case-shaped torque transmission member as described above. The present invention that can avoid sliding of the seal portion between the transmission member and the seal member,
This configuration using an electromagnetic clutch is particularly advantageous.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION A seal structure of an embodiment will be described with reference to FIGS.

This seal structure has an electromagnetic coupling 1.
It is used for (rotation side member: electromagnetic clutch) and has the features of claims 1 and 2. Further, the electromagnetic coupling 1 is arranged in the power transmission system on the rear wheel side that is disconnected when driving two wheels in a four-wheel drive vehicle, and the left side of FIG. 1 corresponds to the front side (engine side) of this vehicle. . It should be noted that members and the like to which reference numerals are not given are not shown.

The electromagnetic coupling 1 includes a rotating case 3
(Case-shaped torque transmission member), inner shaft 5 (axial torque transmission member), multi-plate type main clutch 7, ball cam 9, pilot clutch 11, electromagnet 13, housing 14 (stationary side member), dust cover 15, seal ( A seal member) 17, a controller and the like.

The propeller shaft forming a part of the rear wheel power transmission system is a transfer side and a rear differential (a differential device for distributing the driving force of the engine to the left and right rear wheels).
The electromagnetic coupling 1 is disposed between the transfer side propeller shaft and the rear differential side propeller shaft.

The housing 14 is supported on the vehicle body side by a support metal member fixed to the floor panel of the vehicle body and a flexible support member, and is prevented from rotating.

The rotating case 3 includes a bottomed cylindrical member 19 (case-shaped torque transmitting member) made of aluminum alloy (non-magnetic material) and a rear rotor made of iron-based alloy (magnetic material). 21 and the like.

The rotor 21 is screwed into the rear side opening of the cylindrical member 19 and is fixed by the double nut function of the nut 23.

The front end of the cylindrical member 19 is supported by the housing 14 via ball bearings 25 of both-side seal type, and the rotor 21 is housed via the ball bearing 27 of both-side seal type and the core 29 of the electromagnet 13. 1
It is supported by 4.

The front end of the cylindrical member 19 has a stud bolt 31.
The companion flange is fixed by this, and the joint fork of the joint is integrally formed on this companion flange.

The cylindrical member 19 is connected to the propeller shaft on the transfer side through this joint, and the driving force of the engine is transmitted through these power transmitting members to the cylindrical member 1.
9 (rotating case 3).

The inner shaft 5 penetrates the rotating case 3 from the rear side, its front end is supported by the cylindrical member 19 by the ball bearing 33, and its rear side is supported by the rotor 21 by the needle bearing 35. The inner shaft 5 is axially positioned with respect to the rotating case 3 by snap rings 37 and 39 and a ball bearing 33.

A connecting shaft 41 is spline-connected to the inner shaft 5. The connecting shaft 41 is connected to a companion flange by a bolt, and a joint fork of a joint is integrally formed on the companion flange.

The connecting shaft 41 is connected to the rear differential side propeller shaft via this joint, and the rotation of the inner shaft 5 is transmitted to the rear differential through these power transmission members.

The cylindrical member 19 and the rotor 21 of the rotating case 3
An O-ring 43 is arranged between and. An X ring 45, which is a seal having an X-shaped cross section, is arranged inside the needle bearing 35 between the rotor 21 and the inner shaft 5. These O-rings 43 and X
The electromagnetic coupling 1 (rotating case 3) is sealed by the ring 45.

The sealed rotating case 3 has a cylindrical member 1
Oil is injected through an oil hole 47 provided in the valve 9, and after the oil is injected, a check ball 49 is press-fitted into the oil hole 47 and sealed. Further, the cylindrical member 19 is provided with a space 51 serving as an oil flow path at a position corresponding to the oil hole 47.

The main clutch 7 is arranged between the rotating case 3 and the inner shaft 5, and its outer plate 53 is connected to a spline portion 55 formed on the inner circumference of the rotating case 3 (cylindrical member 19). The inner plate 57 is connected to a spline portion 59 formed on the outer periphery of the inner shaft 5.

The ball cam 9 is the pressure plate 6
1 and the cam ring 63.

The inner circumference of the pressure plate 61 is connected to the spline portion 59 of the inner shaft 5,
The cam thrust force of the ball cam 9 presses the main clutch 7 against the rotating case 3 to engage them.

The cam ring 63 is arranged on the outer periphery of the inner shaft 5 so as to be rotatable relative to the inner shaft 5.
A thrust bearing 65 and a washer 67 that receive the cam reaction force of the ball cam 9 are disposed between the rotor 21 and the rotor 21.

The pilot clutch 11 includes the rotating case 3
The outer plate 69 is connected to the spline portion 55 of the rotating case 3, and the inner plate 71 is connected to the spline portion 73 formed on the outer periphery of the cam ring 63.

An armature 75 is arranged between the pilot clutch 11 and the pressure plate 61, and its outer periphery is connected to the spline portion 55 of the rotating case 3 so as to be movable in the axial direction.

The core 29 of the electromagnet 13 has a housing 14
It is press-fitted into the cylindrical hole 77 formed in, and supports the rotor 21 via the ball bearing 27 as described above. Further, the core 29 penetrates into the recess 79 formed in the rotor 21 via an appropriate air gap, and is axially positioned with respect to the rotor 21 via the snap rings 81 and 83 and the ball bearing 27.

A supporting member 87 is engaged with the groove 85 formed in the core 103, and the supporting member 87 is engaged with an engaging portion 89 formed in the cylindrical hole 77 portion of the housing 14, The electromagnet 13 (core 29) is prevented from rotating.

The lead wire 91 of the electromagnet 13 is connected to the support member 87.
Clipped to and through grommet 93 housing 1
4 is connected to an in-vehicle battery.

The rotor 21, the pilot clutch 11 and the armature 75 form the magnetic path of the electromagnet 13.

The rotor 21 is divided into a radially outer side and an inner side by a ring 95 of non-magnetic austenitic stainless steel. In addition, the pilot clutch 11
In each of the plates 69 and 71, notches 97 provided at equal intervals in the circumferential direction and bridge portions that connect these notches 97 are provided at radial positions corresponding to the rings 95. The ring 95 and the notch 97 prevent the magnetic force from being short-circuited on the magnetic path.

The controller performs excitation of the electromagnet 13, control of excitation current, stop of excitation, and the like.

When the electromagnet 13 is excited, a magnetic loop 99 is generated in the magnetic path, the armature 75 is attracted, the pilot clutch 11 is pressed and engaged, and a pilot torque is generated.

When the pilot torque is generated, the driving force of the engine is applied to the ball cam 9 from the rotating case 3 through the pilot clutch 11 and the cam ring 63 according to the magnitude of the pilot torque, and the generated cam thrust force causes the pressure plate to move. The main clutch 7 is pressed and fastened via 61, and the electromagnetic coupling 1 is connected.

As described above, the cylindrical member 19 of the rotating case 3 is made of a non-magnetic aluminum alloy, so that the magnetic flux is prevented from leaking from the magnetic loop 99 to the cylindrical member 19 side, and the armature 75 is provided. Since the magnetic force is efficiently guided to the pilot clutch 11, a predetermined pilot torque can be obtained by the pilot clutch 11, and a predetermined coupling torque can be obtained by the electromagnetic coupling 1.

When the electromagnetic coupling 1 is connected, the driving force of the engine is transmitted from the inner shaft 5 to the rear diff through the propeller shaft on the rear diff side, etc., and distributed from the rear diff to the left and right rear wheels so that the vehicle is 4 It will be in a wheel drive state, improving the running performance on rough roads and the stability of the vehicle body.

At this time, the electromagnet 13 is controlled by the controller.
When the exciting current is adjusted to control the magnetic force, the slip ratio of the pilot clutch 11 changes and the pilot torque changes, so the cam thrust force of the ball cam 9 changes and the connecting force of the main clutch 7 (via the electromagnetic coupling 1 The magnitude of the driving force sent to the rear wheels can be adjusted.

By adjusting the connecting force as described above, the driving force distribution ratio between the front and rear wheels can be arbitrarily controlled.
If such control is performed during turning, the maneuverability and stability of the vehicle are improved.

When the excitation of the electromagnet 13 is stopped, the pilot clutch 11 is released, the cam thrust force of the ball cam 9 disappears, the main clutch 7 is opened, and the coupling of the electromagnetic coupling 1 is released.

When the coupling of the electromagnetic coupling 1 is released, the rear differential side propeller shaft is disconnected from the rear wheels, and the vehicle is set to the front-wheel-drive two-wheel drive state, and the fuel economy of the engine is improved.

The hollow inner shaft 5 is partitioned by the wall portion 101, and a capacity increasing space portion 103 for increasing the amount of oil enclosed is formed. This space-increasing space 1
In 03, the injected oil and air are stored like other parts inside the rotating case 3.

The capacity increasing space portion 103 includes the space 51 between the inner shaft 5 and the cylindrical member 19 and the ball bearing 33.
Through the radial flow passages 105 formed in the inner shaft 5, respectively, to communicate with the main clutch 7 side.

When the electromagnetic coupling 1 (inner shaft 5) rotates, the oil in the capacity increasing space 103 passes through the space 51, the ball bearing 33 and the radial passage 105 by the centrifugal force, and the bearing 33, the main clutch 7, The ball cam 9, pilot clutch 11, bearing 65, washer 67, etc. are lubricated and cooled.

An oil hole 107 is provided in the inner plate 57 of the main clutch 7 to promote the movement of oil to the ball cam 9, the pilot clutch 11 and the bearing 65 side, thereby improving the lubrication / cooling effect of these. I am letting you.

A through hole 109 is formed in the pressure plate 61. The through-hole 109 reduces the resistance to movement of the pressure plate 61 due to oil, improves the operation response of the main clutch 7, and serves as an oil flow path, promoting the movement of oil toward the ball cam 9 and the pilot clutch 11. However, the lubrication and cooling effects of these are improved.

The housing 14 includes a front housing 111 and a rear housing 1 each made of an iron alloy.
It is composed of 13 and each housing 111, 113
Are aligned with each other by stud pins 115 and then fixed to each other with bolts.

The electromagnetic coupling 1 is protected by the housing 14 from foreign matters such as stones flying during traveling and collisions with stepped portions and convex portions encountered during traveling.

The dust cover 15 is made of an iron-based alloy and is press-fitted into the front end of the cylindrical member 9.

Further, the seal 17 is arranged between the dust cover 15 and the front end of the front housing 111 (a portion of the stationary member facing the dust cover).

Further, a proper gap is formed between the dust cover 15 and the front housing 111 to form a seal portion 117.

Further, the rear housing 113 and the rotor 21
A seal 119 is disposed between and.

The seal 17, the seal portion 117, and the seal 119 prevent foreign matters such as dust and water from entering the space formed between the housing 14 and the rotating case 3 from the outside.

Therefore, the core 29 of the electromagnet 13 and the rotor 2 are
No water or dust will enter the air gap between the rotor 21 (rotating case 3) due to the trapping of dust, freezing of water, generation of rust, etc. Function is maintained normally.

Further, by preventing the intrusion of water and dust, the ball bearings 25 and 27 of the both-side seal type are provided.
It becomes possible to use a non-sealing type bearing instead of, and the cost can be reduced accordingly.

The seal 17 is composed of a support fitting 121 (support member) and a seal portion 123 which are integrally formed, and the seal portion 123 has three lips 125, 127,
129 is formed.

The support bracket 121 is the front housing 11.
It is pressed into 1. In addition, the lip 1 of the seal portion 123
25 and 127 are in contact with the dust cover 15, and the lip 129 is in contact with the dust cover 15.

In this way, the seal portion 123 (lip 12
5, 127) does not slide with the dust cover 15 made of an iron-based alloy and having a high hardness, and does not slide with the cylindrical member 19 made of an aluminum alloy and having a low hardness. Therefore, the cylindrical member 19 has lips 125, 127. Abnormal wear due to sliding and sliding can be avoided.

The seal 119 is composed of a support fitting 131 and a seal portion 133 which are integrally formed. The support fitting 131 is press-fitted into the inner periphery of the rear housing 113, and the seal portion 133 is in contact with the outer periphery of the rotor 21, but the rotor 21 is made of an iron-based alloy and has a high hardness. It will not be worn out, and will have sufficient durability.

A disc spring 135 and a washer 137 are provided between the core 29 of the electromagnet 13 and the rear housing 113.
And the disc spring 135 presses the rotating case 3 and the inner shaft 5 forward by its urging force,
Axial play between the electromagnetic coupling 1 and the housing 14 is reduced.

Since the axial play is reduced, the axial vibration is removed from the sliding portion between the seal portions 123 and 133 of the seals 17 and 119 and the mating member (cylindrical member 19 and rotor 21), and the sliding movement is eliminated. The durability of the moving part has been greatly improved.

A large number of cooling fins 139 are provided on the outer circumference of the front housing 111 which constitutes the housing 14.
Are provided to cool the space inside the housing 14 and the electromagnetic coupling 1 arranged in this space.

Thus, the electromagnetic coupling 1 and its seal structure are constituted.

In this seal structure, in the electromagnetic coupling 1, the seal portion 123 of the seal 17 (lip 12
5, 127) made of iron alloy and has high hardness dust cover 1
By sliding with 5, the cylindrical member 19 is released from sliding with the seal portion 123, and wear due to sliding is avoided.

Therefore, the cylindrical member 19 can be made of aluminum alloy, and the weight of the electromagnetic coupling 1 is greatly reduced.

Due to this weight reduction, the inertia of the electromagnetic coupling 1 is reduced, the rotational imbalance and the vibration caused thereby are reduced, and the fuel consumption of the engine is improved.

Further, since the dust cover 15 is used for improving the abrasion resistance, it is not necessary to additionally provide a member such as a collar in order to improve the abrasion resistance. Increases in parts management costs and assembly work costs can be avoided.

Further, in this seal structure, the seal 17 is arranged between the dust cover 15 and the front housing 111 (stationary member) (the dust cover 15 and the seal 17 are arranged at the same position), Compared with the conventional coupling in which the seal and the dust cover are arranged at different positions, the arrangement space is smaller, and the electromagnetic coupling 1 including the dust cover 15 is made compact by that much.

Further, since the cylindrical member 19 is made of aluminum alloy (non-magnetic material), leakage of magnetic flux is prevented, the loss of the battery which is the power source of the electromagnet 13 is reduced, and the fuel efficiency of the engine is further improved. The present invention in which the cylindrical member 19 can be made of a non-magnetic material is particularly advantageous in a rotating side member that engages and disengages the clutch by an electromagnet like the electromagnetic coupling 1.

In addition to light metal such as aluminum alloy, the cylindrical member 19 may be austenitic stainless steel, which has relatively low hardness among steels, and if the required strength is obtained, It may be made of plastic.

In the above embodiment, the main clutch 7 is the case-shaped torque transmitting member (rotating case 3).
Is a mechanism for transmitting a driving force between the shaft-shaped torque transmission member (inner shaft 5) and the outer plate 53 and the inner plate 57 are meaningless. Similarly, the rotating case 3 and the inner shaft 5, which are connected to each other, are also essential constituent members of the main clutch 7.

For the same reason, the rotating case 3, the cam ring 63, the outer plate 69, and the inner plate 71 are essential components of the pilot clutch 11.

The ball cam 9 is a cam mechanism for converting the transmitted driving torque into the pressing force of the main clutch 7, and includes the pressure plate 61 and the cam ring 6.
3, not only the cam surfaces formed on them, the balls arranged between them, but also the inner shaft 5 that transmits the driving force to the pressure plate 61, the rotating case 3 that transmits the driving force to the cam ring 63, and the pilot clutch 11.
Are essential components.

Further, the main clutch 7 and the pilot clutch 11 may be any type of clutch as long as it is a friction clutch, such as a single plate clutch or a cone clutch, in addition to the multi-plate clutch. Further, these may be wet type or dry type.

Further, in the invention of claim 2, the electromagnetic clutch is not limited to the structure of the embodiment in which the pilot clutch and the cam mechanism are used to engage the main clutch, but is operated by an electromagnet or a spring. Alternatively, the armature may directly press the clutch.

Further, the seal structure of the present invention can be widely applied to the rotating side member, and not only the coupling for interrupting the torque by the clutch as in the embodiment but also the torque for transmitting the torque by the shear resistance of the viscous fluid. It is also possible to implement the coupling as in the conventional example in which the connection and disconnection is not performed.

[0086]

According to the seal structure for a coupling according to the first aspect of the present invention, the rotating member of the coupling is released from abrasion with sliding and sliding with respect to the sealing member. By using light metal, the coupling can be made lighter and the moment of inertia can be reduced to improve the fuel efficiency of the prime mover.

Further, a dedicated member for improving the wear resistance of the rotating member is not required, and the increase in the number of parts and the parts cost, the parts management cost, the assembly work cost and the like can be avoided.

The coupling seal structure described in claim 2 can obtain the same effect as that of the structure of claim 1.

Further, by using a non-magnetic material such as aluminum alloy or austenitic stainless steel for the case-shaped torque transmitting member of the electromagnetic clutch (rotating member) which is intermittently operated by the electromagnet, leakage of magnetic flux is prevented, In the vehicle-mounted device, the loss of the battery that is the power source of the electromagnet is reduced to improve the fuel efficiency of the prime mover.However, as described above, by attaching the dust cover to the case-shaped torque transmission member, The present invention capable of avoiding the sliding of the seal portion between the linear torque transmission member and the seal member is particularly advantageous in this configuration using the electromagnetic clutch.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an electromagnetic coupling using an embodiment.

FIG. 2 is a cross-sectional view showing a main part of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Electromagnetic coupling (rotation side member: electromagnetic clutch) 3 Rotation case (case-shaped torque transmission member) 5 Inner shaft (axial torque transmission member) 7 Main clutch 11 Pilot clutch (clutch interrupted by electromagnet) 13 Electromagnet 14 Housing (stationary member) 15 Dust cover 17 Seal (seal member) 19 Cylindrical member (case-shaped torque transmission member) 121 made of aluminum alloy 121 Support metal fitting (support member) 123 Seal part 125, 127 Lip (sliding of seal) Part)

Claims (2)

[Claims] 1. A seal structure provided between a stationary member and a rotating member exposed to the outside in the vicinity of the stationary member, wherein the sealing structure is between the rotating member and the stationary member. A dust cover for preventing foreign matter from entering the rotary member side is provided, and a seal member is provided on a stationary member near the dust cover to bring the seal member into contact with the dust cover so that the seal member is placed between the dust cover and the dust cover. Seal structure characterized by sliding with. 2. The electromagnetic clutch according to claim 1, wherein the rotation-side member engages and disengages a clutch disposed between the case-shaped torque transmission member and the shaft-shaped torque transmission member by an electromagnet. The seal structure is characterized in that the dust cover is attached to the case-shaped torque transmission member.