JP2004176782A - Seal and clutch release bearing device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a seal for a clutch release bearing having increased sealing effect and a clutch release bearing device using the seal. <P>SOLUTION: Even when a vehicle having the clutch release bearing device passes across a muddy stream, most slurry is prevented from invading therein by a second lip part 17d in contact with a sliding member 17e. Even if foreign matter invades therein, large solid foreign matter is caught by a labyrinth seal part 17c to prevent the slurry from entering therein through the second lip part. Semi-fluid foreign matter, even if passed through the labyrinth seal part 17d, is caught by a first lip part 17b to prevent the slurry from entering therein through the first lip part. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a sealing technique having excellent sealing properties, and more particularly to a sealing technique suitable for a clutch release bearing.
[0002]
[Prior art]
When operating a clutch, which is a power interrupting device using a friction plate, mounted on a vehicle such as an automobile, a tractor, a forklift, etc., the diaphragm spring of the clutch cover is axially pressed by a release fork as an input member. As a result, the urging force of the diaphragm spring is released from the friction plate to disconnect the power transmission.
[0003]
By the way, the release fork is usually arranged on the fixed side of the vehicle body or the like, but the clutch cover is attached to the flywheel or the like of the engine and rotates integrally therewith. Therefore, when the release fork directly presses the diaphragm spring of the clutch cover, wear of the contact portion is caused. Therefore, a clutch release bearing including a rotating wheel that abuts against a diaphragm spring and integrally rotates, a non-rotating bearing holding member that holds the bearing in a predetermined state and receives an input from a release fork. Is provided between a diaphragm spring and a release fork, for example, as shown in Patent Document 1 below.
[Patent Document 1]
JP 2001-280367 A
[0004]
As described above, the clutch is configured such that the friction plate is interposed between the relatively rotating metal surfaces and the power is transmitted by using the frictional force acting on each other, so that the clutch (engine) Wear powder such as friction plates scatter from the side. However, if such foreign matter enters between the raceway of the clutch release bearing and the rolling element, there is a possibility that the raceway and the rolling element will be worn early. Therefore, in the clutch release bearing device disclosed in Patent Document 1, the inner ring and the outer ring are sealed with a labyrinth seal (or a so-called fine contact seal having a small contact force), and the inner ring and the outer ring are further sealed. A lip is provided to prevent foreign matter from entering.
[0005]
[Problems to be solved by the invention]
By the way, in recent years, the heat generation amount has been increased with the improvement of engine performance, and a cooling air hole is provided in a housing surrounding the clutch in order to prevent a temperature rise around the engine due to the increase in the heat generation amount. It is thought that. However, there is a possibility that foreign matter such as dust and water may enter from outside through the air holes. According to the seal disclosed in Patent Document 1, by combining a labyrinth seal or the like with the lip portion, a sufficient sealing effect can be obtained in normal use.
[0006]
However, it is required to further enhance the foreign-matter intrusion function especially in a severe use environment. For example, in a case of a four-wheel drive vehicle that can travel on uneven terrain or in some cases cross a river, a large amount of muddy water may enter the clutch release bearing device during traveling. Design is required.
[0007]
In view of the foregoing, an object of the present invention is to provide a clutch release bearing seal having a higher sealing effect and a clutch release bearing device using such a seal.
[0008]
[Means for Solving the Problems]
To achieve the above object, the seal of the present invention
In the seal that seals between the inner ring and outer ring of the clutch release bearing,
A labyrinth seal portion extending from one of the inner ring and the outer ring and maintained in a non-contact state with the other ring;
A first lip portion disposed inward of the labyrinth seal portion and maintained in contact with the other wheel;
A second lip portion disposed outside the labyrinth seal portion and kept in contact with the other wheel.
[0009]
[Action]
According to the seal of the present invention, in a seal for sealing between an inner ring and an outer ring of a clutch release bearing, a labyrinth extending from one of the inner ring and the outer ring and maintained in a non-contact state with the other ring A seal portion, a first lip portion disposed inward of the labyrinth seal portion, and maintained in contact with the other wheel, and a first lip portion disposed outside of the labyrinth seal portion, Since the second lip portion is kept in contact with a ring (for example, when a sliding member is attached, such a sliding member is also included in the other ring), the second lip portion is not provided. Even under severe use conditions such as terrain running, first, the second lip portion can prevent most foreign matter from entering, and even if there is foreign material that has passed through the second lip portion, the labyrinth seal portion or the second 1 lip Since it prevents from entering inward it can exhibit more effectively sealing action. The labyrinth seal portion is opposed to the other ring via a narrow gap, and a change in cross-sectional area is used to attenuate the energy of gas passing therethrough to prevent foreign matter from entering. A material that performs its function.
[0010]
Further, it is preferable that a portion where the second lip portion abuts is located radially outward of the clutch release bearing from a portion where the first lip portion abuts. This is because the peripheral speed of the second lip is higher than that of the first lip, so that a draining effect is generated, and foreign substances can be prevented from entering from the outside.
[0011]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a view of a clutch release bearing device including a seal according to an embodiment of the present invention as viewed from a release fork side. FIG. 2 is an axial sectional view taken along the line II-II of FIG. 1 and viewed in the direction of the arrow.
[0012]
2, the clutch release bearing device includes a clutch release bearing 10, a guide sleeve 20 as a bearing holding member, and a spring member 30 as a connecting member. The clutch release bearing 10 includes a substantially tubular inner ring 11 having a contact portion 11a at the left end, a short tubular outer ring 12 concentrically enclosing the inner ring 11, and rolling between the inner ring 11 and the outer ring 12. A plurality of balls 15 movably arranged, a retainer 16 for holding the balls 15 at predetermined intervals, a seal 17 for sealing a space defined by the inner ring 11 and the outer ring 12 on both axial sides of the balls 15, 18 The inner race 11 is rotatably supported by the outer race 12. The contact portion 11a of the inner ring 11 has a shape that is turned outward in the radial direction, and comes into contact with a diaphragm spring of a clutch cover (not shown). The end of the inner ring 11 on the side opposite to the contact portion 11a is left as blank by pressing, so that cutting is not performed and manufacturing cost is reduced.
[0013]
On the other hand, the guide sleeve 20 is made of molded resin, and has a cylindrical main body 21, a flange portion 22 extending in the radial direction from the outer periphery near the center of the main body 21, and a radially outward portion of the flange portion 22. An outer wall portion 23 protrudes leftward in the axial direction at the end, and a guide portion 25 (FIG. 1) protrudes axially at a radially outer end of the flange portion 22. A guide shaft (not shown) extends inside the main body 21, and the main body 21 is slidable on the guide shaft. Note that an enlarged diameter portion 24 is provided inside the main body 21. The enlarged diameter portion 24 functions to prevent foreign matter from being caught when the main body 21 slides on the guide shaft. The outer wall portion 23 is provided outside the clutch release bearing 10 and serves as a radial movement restricting portion. A gap 27 is formed between the outer periphery of the outer race 12 and the inner periphery of the outer wall 23 so that the clutch release bearing 10 can be moved in the radial direction. A horizontal groove 26 is provided in the middle of the flange portion 22, and a clip (not shown) for fixing a release fork is inserted into the horizontal groove 26.
[0014]
As apparent from FIG. 1, the spring member 30 provided with two members having the same shape has a function of attaching the clutch release bearing 10 to the guide sleeve 20. The stopper 22g of the guide sleeve 20 functions to engage with the notch 38 of the spring member 30 when the spring member 30 is attached to the guide sleeve 20, and to prevent the spring member 30 from being pushed further inward. I do.
[0015]
As shown in FIGS. 1 and 2, a reinforcing member 40 is provided on the release fork side of the guide sleeve 20. The reinforcing member 40 includes a cylindrical portion 41, a plate-shaped anvil portion 42 protruding upward and downward from substantially the center of the cylindrical portion 41, and a flange portion 43 extending radially from an end of the cylindrical portion 41. Is formed by pressing a relatively thin plate, followed by quenching. This prevents remarkable wear from occurring at the contact portion with the release fork.
[0016]
The cylindrical portion 41 is fitted to the main body 21 with a gap when attached to the guide sleeve 20, and can support the guide sleeve 20 in a reinforcing manner when receiving a load. The upper and lower parts of the cylindrical part 41 are extended so as to correspond to the anvil part 42 to form a rectangular part 41a (FIG. 1). The rectangular portion 41a has a function of guiding the release fork and a function of ensuring rigidity of the anvil portion.
[0017]
As shown in FIG. 1, the flange portion 43 of the reinforcing member 40 is formed with a rectangular notch 43 a in a circumferential portion, and the notch 43 a is located at a position corresponding to the flange portion 22 of the guide sleeve 20 at the time of mounting. By engaging with the formed projection 22f, the rotation preventing and positioning of the reinforcing member 40 are achieved.
[0018]
Next, the operation of the clutch release bearing device according to the embodiment of the present invention will be described below. In FIG. 1, a release fork (not shown) pivots, and its tip contacts an anvil portion 42 of a reinforcing member 40 to apply a constant load. Since the reinforcing member 40 is relatively thick and has sufficient rigidity, it can receive a large load received from the release fork. The clutch release bearing device slides in the axial direction on a guide shaft (not shown) in response to an input from a release fork to bring the contact portion 11a of the inner ring 11 into contact with a diaphragm spring of a clutch cover (not shown). In such a case, even though the diaphragm spring is rotating, the inner ring 11 is rotatable, so that the inner ring 11 rotates integrally with the diaphragm spring after abutment, and the diaphragm spring is moved by the clutch release bearing device moving in the axial direction. The clutch is operated by being pressed.
[0019]
Since the spring member 30 has an appropriate plate thickness and supports the clutch release bearing 10 with respect to the guide sleeve 20 only by the frictional force acting between the pressing portion 32 and the outer ring 12, the bearing 10 is The guide sleeve 20 is movable in the radial direction. Therefore, when the contact portion 11a of the inner ring 11 contacts the diaphragm spring, if there is an eccentricity between the two, a known force for positioning the bearing 10 concentrically occurs, whereby the bearing 10 is moved in the radial direction. And self-centering will be achieved. The outer wall 23 of the guide sleeve 20 has a function of restricting the bearing 10 from moving outward in the radial direction by a predetermined amount or more. Further, since the outer ring of a general ball bearing does not have a flange in many cases, if the outer ring is sandwiched by the spring member 30 as in the present embodiment, it is not necessary to modify the outer ring itself and an existing one can be used. It can be used and can contribute to cost reduction.
[0020]
By the way, the clutch release bearing 10 is such that the ball 15 rolls along the rolling path of the inner ring 11 and the outer ring 12, so that it is particularly difficult to infiltrate foreign matters among the elements constituting the clutch release bearing device. . Therefore, in the clutch release bearing of the related art, the labyrinth seal portion and the lip portion are combined to prevent wear powder of the clutch from entering the inside of the bearing.
[0021]
On the other hand, it is required to further enhance the foreign matter intrusion function particularly under a severe use environment. According to the present embodiment, such a request can be met.
[0022]
3 is an enlarged sectional view in the axial direction of the clutch release bearing 10 shown in FIG. 2, in which the left side of FIG. 3 is the engine side and the right side is the transmission side. In FIG. 3, circumferential grooves 12a and 12b are formed on the inner circumference of both ends of the outer race 12. An outer edge of a seal 18 having a substantially disk-shaped cored bar 18a and a lip 18b abutting on an end surface of the inner ring 11 is attached to the transmission-side circumferential groove 12b. It prevents foreign matter from entering through the surface and prevents grease from flowing out. Since the flange portion 22 (FIG. 1) of the guide member 20 is disposed on the right side of the seal 18 (on the transmission side), there is a low possibility that foreign matter such as muddy water is scattered. The intrusion of foreign matter can be effectively prevented only by bringing the 18b into contact with the inner ring 11.
[0023]
On the other hand, an outer edge of a contact-type seal 17 is attached to the circumferential groove 12a on the engine side. The seal 17 includes a substantially disk-shaped core 17 a, a first lip 17 b extending from the inner edge of the core 17 a and abutting against the outer peripheral portion of the inner ring 11, and a core having a triangular cross-section and a core closer to the engine than the lip 17 b. A labyrinth seal portion 17c extending from the inner edge of the metal 17a and being slightly separated from the outer peripheral portion of the inner ring 11; and a tapered shape extending from the inner edge of the core bar 17a on the engine side of the labyrinth seal portion 17c. 11 has a second lip portion 17d abutting on a flange portion of a sliding member 17e having an L-shaped cross section attached to the outer peripheral surface of the sliding member 17e. The lip portions 17b and 17d and the labyrinth seal portion 17c are integrally formed of rubber, but may be formed separately. The sliding member 17e is made of metal, and can be fixed to the inner ring 11 by press fitting, bonding, welding, or the like.
[0024]
As described above, even in a situation where the vehicle equipped with the clutch release bearing device of the present embodiment crosses a turbid current or the like, most muddy water is removed by the second lip portion 17d abutting on the sliding member 17e. Further intrusion into the inside is prevented, and even if a foreign matter enters, a large solid foreign matter is caught by the labyrinth seal portion 17c and is prevented from entering further. Further, even if the (semi-) fluid foreign matter can pass through the labyrinth seal portion 17c, it is trapped by the first lip portion 17b and is prevented from entering inward. Therefore, the wear of the balls 15, the rolling races of the inner race 11 and the outer race 12 can be minimized, and the life of the clutch release bearing 10 can be extended.
[0025]
FIG. 4 is an axial sectional view of a clutch release bearing 110 including a seal according to the second embodiment. Note that, in the present embodiment, the same reference numerals are given to the common portions with respect to the embodiment shown in FIG.
[0026]
This embodiment differs from the embodiment shown in FIG. 3 in the configuration of the sliding member and the seal. More specifically, the sliding member 117e has a substantially U-shaped cross section, that is, has a configuration in which ends of one side (engine side) of a double cylinder are connected to each other by a flange portion. In accordance with this, the second lip portion 117d of the seal 117 extends cylindrically in the axial direction so as to abut on the outer cylindrical surface of the sliding member 117e.
[0027]
FIG. 5 is an axial sectional view of a clutch release bearing 210 including a seal according to the third embodiment. Note that, in the present embodiment, the same reference numerals are given to the common portions with respect to the embodiment shown in FIG.
[0028]
This embodiment is different from the embodiment shown in FIG. 3 in that the sliding member is omitted by devising the cutting of the inner ring. More specifically, the inner ring 211 having a thick wall on the engine side has a step portion 211a formed on the outer peripheral surface thereof. The second lip portion 17d of the seal 17 is in contact with the radially extending surface of the step portion 211a.
[0029]
The feature common to the embodiments of FIGS. 3 to 5 is that the portion of the sliding member or inner ring contacted by the second lip portion is shifted from the outer peripheral surface of the inner ring contacted by the first lip portion to the clutch release bearing. Is located radially outward of the
[0030]
As described above, the present invention has been described with reference to the embodiments. However, the present invention should not be construed as being limited to the above-described embodiments, and it is needless to say that modifications and improvements can be made as appropriate. For example, a fine contact seal may be provided instead of the labyrinth seal.
[0031]
【The invention's effect】
According to the seal of the present invention, in a seal for sealing between an inner ring and an outer ring of a clutch release bearing, a labyrinth extending from one of the inner ring and the outer ring and maintained in a non-contact state with the other ring A seal portion, a first lip portion disposed inward of the labyrinth seal portion, and maintained in contact with the other wheel, and a first lip portion disposed outside of the labyrinth seal portion, Since the second lip portion is maintained in contact with the wheel, even under severe use conditions such as running on uneven terrain, the second lip portion can prevent most foreign matter from entering, and Even if there is foreign matter passing through the second lip portion, the labyrinth seal portion or the first lip portion can prevent the foreign material from intruding inward, so that the sealing effect can be more effectively exerted.
[Brief description of the drawings]
FIG. 1 is a view of a clutch release bearing device according to an embodiment of the present invention as viewed from a release fork side.
FIG. 2 is an axial sectional view taken along the line II-II of FIG. 1 and viewed in a direction indicated by an arrow.
FIG. 3 is an axial sectional view of the clutch release bearing 10 including the seal according to the first embodiment.
FIG. 4 is an axial sectional view of a clutch release bearing 110 including a seal according to a second embodiment.
FIG. 5 is an axial sectional view of a clutch release bearing 210 including a seal according to a third embodiment.
[Explanation of symbols]
10 Clutch Release Bearing 17 Seal 17a Core 17b First Lip 17c Labyrinth Seal 17d Second Lip 17e, 117e Sliding Member 20 Guide Sleeve 30 Spring Member 40 Reinforcing Member

Claims (3)

In the seal that seals between the inner ring and outer ring of the clutch release bearing,
A labyrinth seal portion extending from one of the inner ring and the outer ring and maintained in a non-contact state with the other ring;
A first lip portion disposed inward of the labyrinth seal portion and maintained in contact with the other wheel;
A second lip disposed outside the labyrinth seal portion and maintained in contact with the other wheel. The seal according to claim 1, wherein a portion where the second lip portion abuts is located radially outward of the clutch release bearing from a portion where the first lip portion abuts. A clutch release bearing device comprising the seal according to claim 1.

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