GB2307286A - A self centring clutch release bearing - Google Patents

Description

1 - Clutch Release Bearing Apparatus 2307286

BACKGROUND OF THE INVENTION Field of the Invention

This invention relates to a clutch release bearing apparatus. Related Background Art

When a clutch which is a power connecting- disconnecting device using a friction plate carried on a vehicle or the like is to be operated, the diaphragm spring of a clutch cover is pressed in the axial direction thereof by a shift fork which is an input member to thereby release the biasing force of the spring from the friction plate and effect the cutting off of power transmission.

Now, the shift fork is usually disposed on the fixed side of the vehicle or the like, but the clutch cover is mounted on the flywheel or the like of an engine and is adapted to rotate therewith. Accordingly, if the shift fork directly presses the diaphragm spring of the clutch cover, the wear of the bearing portion will result. So, a clutch release bearing apparatus comprising a release bearing including a rotatable wheel bearing against and rotatable with the diaphragm spring, and an unrotatable bearing holding member holding this bearing in a predetermined state and adapted to receive an input from the shift fork is provided between the diaphragm spring and the shift fork, as shown, for example, in Japanese Utility Model Application Laid-Open No. 567124.

In the clutch release bearing apparatus disclosed in this Japanese Utility Model Application Laid-Open No. 56-7124, the tip end portion of the outer race of the bearing is opposed to the diaphragm spring, while a flange portion is provided on the rear end of the inner race of the bearing in opposed relationship with the flange portion of a guide sleeve. Also, the bearing is mounted on the guide sleeve in such a manner as to hold the flange portions in the axial direction thereof by a leaf spring. If the flange portion of the guide sleeve is pushed from the rear thereof by the tip end of the shift fork, the entire bearing apparatus is movable in the axial direction thereof so that the tip end portion of the outer race may bear against the diaphragm spring.

The flange portion of the inner race is biased by a leaf spring so as to be radially movable relative to the fl-ange portion of the guide sleeve and therefore, when the flange portion of the guide sleeve is pushed from the rear thereof by the shift fork and the outer race of the bearing bears against the diaphragm spring of the clutch, the bearing is adapted to be automatically aligned even if there is eccentricity 3 therebetween.

Now, in the prior art, the bearing holding member (guide sleeve) of the clutch release bearing apparatus has been made of steel, but in recent years, a desire to make it of resin has appeared from the viewpoint of lighter weight or the like. However, if the guide sleeve is simply made of resin, the wear, deformation, etc. of the bearing portion will result because the flange portion of the guide sleeve is a portion which receives the force from the shift fork. So, there is conceived to make the leaf spring for suppressing the radial movement of the bearing of steel and install it on the bearing portion of the shift fork to thereby prevent the wear and deformation of the bearing portion.

However, the construction as described above suffers from the following problems. To hold the bearing for movement in the radial direction to make it capable of being aligned, the leaf spring must hold the rotatable wheel of the bearing and the flange portion of the guide sleeve therebetween with a light load of the order of 2 to 15 kgf. However, when for example, the plate thickness of the leaf spring is set to a relatively great value of 1 mm. or greater, the manufacture thereof becomes difficult from the viewpoint of the allowable dimensional difference between necessary parts. This is because when the plate thickness is made great, the spring constant of the leaf spring becomes high and the holding force thereof becomes greatly irregular even for any slight dimensional error and therefore the dimensional error must be strictly controlled. On the other hand, the pressing load of the shift fork is very high and therefore, when an attempt is made to receive that load by the leaf spring, the flange portion of resin striking against the back of the leaf spring becomes flexed or depressed if the plate thickness of the surface against which the shift fork bears is relatively small, whereby the leaf spring may be broken. To prevent this, it is necessary to set, for example, the plate thickness of the leaf spring to 1.5 mm or greater. However, if the plate thickness is thus made great, there will arise the above-noted problem of dimension control.

In order to avoid such a problem, there is conceived a construction in which discretely from the leaf spring, a reinforcing plate is provided between the shift fork and the flange portion of the guide sleeve-so as to receive a part of the pressing load from the shift fork, whereby the plate thickness of the leaf spring is made relatively small. In such a construction, however, there is a problem as will be described hereinafter. That is, the shift fork pivotally moves abut a predetermined point and therefore, a force in a direction perpendicular to the axis is created to a certain degree at the bearing point of the shift fork. Accordingly, if the reinforcing plate and the leaf spring are in close contact with each other when the shift fork directly contacts with the leaf spring as well as when the shift fork bears against the reinforcing plate, the force in the direction perpendicular to the axis is also transmitted to the leaf spring, whereby the leaf spring and the guide sleeve in contact therewith may be deformed to thereby spoil the function.

Also, the prior-art leaf spring for fixing the bearing suffers from a problem as will be described hereinafter.

Fig. 27 of the accompanying drawings is a crosssectional view showing the leaf spring 630 according to the prior art on an enlarged scale as it is cut in the axial direction thereof with a flange portion 700 on which it is mounted. The leaf spring 630 is formed by bending a steel plate. In Fig. 27, assembly is done by inserting this leaf spring 630 from the radially outer side of the flange portion 700, and in order to facilitate this insertion into the flange portion 700, an outwardly bent portion 630a is formed on the tip end portion of the leaf spring 630. However, depending on the situation of work, the insertion of this leaf spring 630 is done by groping and at that time, the - 6 leaf spring 630 may be inserted while being shifted rightwardly as viewed in Fig. 27 by a relatively great shift amount A. If in such a case, the axial length B of the bent portion 630a of the tip end of the leaf spring 630 is shorter than the shift amount A, that tip end will bear against the flange portion 700 and the insertion of the leaf spring 630 will become impossible. In order to avoid such an uninsertable state, the axial length B of the bent portion 630a of the tip end of the leaf spring 630 has heretofore been made great to a certain degree to thereby facilitate the insertion thereof. However, such a long bent portion 630a may result in the interference with other part and in terms of design layout, it has been desired to make such a bent portion 630a shorter.

Also, another example of the clutch release bearing apparatus according to the prior art will now be described with reference to Fig. 28 of the accompanying drawings. Fig. 28 is an axial cross sectional view of the clutch release bearing apparatus according to the prior art. In this clutch release bearing apparatus, a disc-like flange 1040 is embedded in and integral with a cylindrical guide sleeve 1020 made of resin. A case 1050 fixed by caulking to the juter race 1012 of a bearing 1010 is disposed at the left in the axial direction of the flange 1040, and is mounted so as to be resiliently held relative to the 7 flange 1040 by a belleville spring 1060 for aligning. If the flange 1040 is pushed from the rear thereof by the tip end of a shift fork, not shown, the entire bearing apparatus is axially movable so that the tip end portion of the inner race 1013 of the bearing may bear against a diaphragm spring, not shown.

The entire bearing 1010 is biased by the belleville spring 1060 so as to be radially movable relative to the flange 1040. Accordingly, even if the bearing 1010 is eccentric, the outer race 1012 radially slides relative to the flange 1040 with a case 1050 when the flange 1040 is pushed from the rear thereof by the shift fork and the inner race 1013 of the bearing 1010 bears against the diaphragm spring of the clutch, whereby the bearing 1010 may be automatically aligned.

Also, in this clutch release bearing apparatus according to the prior art, the flange 1040 is integral with the guide sleeve 1020 and therefore, the following problem arises. Generally, the shift fork is adapted to arcuately move (pivotally move) about a pivot to thereby press the flange 1040. On the other hand, the guide sleeve 1020 and the flange 1040 move only in the axial direction and therefore, slip occurs between the pressing portion of the shift fork and the flange 1040. Even if lubricating oil such as grease is applied to such a portion, it has been impossible to prevent the wear thereof when the apparatus is used for a long - 8 period, aside from a case where the apparatus is used for a short period.

When the bearing portion between the shift fork and the flange 1040 wears, the bearing surface of the flange becomes coarse, thus resulting in an increase in frictional resistance and the hitch of the shift fork, whereby the peak value of the release load may become greater than the initial value. That is, a driver comes to feel the unpleasant feeling that a stronger clutch pedal stepping force is required while he or she uses the vehicle for a long period.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide a clutch release bearing apparatus which can be made light in weight and can achieve the automatic aligning of a bearing, and yet can sufficiently resist the load from a shift fork and is more improved in reliability and is made compact in construction and easy to assemble.

It is another object of the present invention to provide a clutch release bearing apparatus in which the wear between it and a shift fork is reduced to thereby prevent any increase in the peak value of a pedal stepping force.

The clutch release bearing apparatus of the present invention is a clutch release bearing apparatus 9 comprising: a clutch release bearing including an inner race and an outer race disposed concentrically with each other and rotatable relative to each other, one of the races being fixed and the rotatable other race being adapted to bear against the rotatable member of a clutch device; a bearing holding member made of resin and provided with a cylinder portion slidably fitted on a guide shaft, and a flange portion; and a connecting member holding the one race of the clutch release bearing for movement in the radial direction thereof relative to the bearing holding member; characterized in that the connecting member is deformed by assembly, whereby a pressing portion biases the one race toward the bearing holding member, provision is further made of a reinforcing member interposed between an input member and the bearing holding member for receiving an input from the input member and transmitting it to the flange portion of the bearing holding member, the bearing holding member is provided with a projection, the connecting member is provided with a depression adapted to be engaged with the projection during the assembly thereof to thereby prevent the slipping-out of the connecting member, and by the connecting member being assembled, the reinforcing member is adapted to be mounted between the bearing holding member and the connecting member.

The clutch release bearing apparatus of the present invention is further characterized in that a gap is provided in the axial direction between the connecting member and the reinforcing member.

The clutch release bearing apparatus of the present invention is further characterized in that the flange portion of the bearing holding member is formed with a horizontal groove into which a clip for fixing a shift fork is inserted.

The clutch release bearing apparatus of the present invention is further characterized in that the connecting member is inserted from the radial direction relative to the clutch release bearing and the bearing holding member during assembly, and is adapted to hold the one race and the bearing holding member in the axial direction when it arrives at a predetermined position, and the bearing holding member further has guide means for prescribing the axial position of the connecting member relative to the one race during the assembly of the connecting member.

The clutch release bearing apparatus of the present invention is further characterized in that the reinforcing member is supported for movement to an extent exceeding 0.2 mm in a first direction which is a radial direction relative to the bearing holding member and is orthogonal to the pivot of the input member.

The clutch release bearing apparatus of the present invention is further characterized in that the reinforcing member is movable also in a second direction which is a radial direction relative to the bearing holding member and differs from the first direction, but the amount of movement of the reinforcing member in the second direction is smaller than the amount of movement thereof in the first direction.

The clutch release bearing apparatus of the present invention is further characterized in that the inner diameter surface of the reinforcing member is guided by the cylinder portion of the bearing holding member.

The clutch release bearing apparatus of the present invention is a clutch release bearing apparatus comprising:

a clutch release bearing including an inner race and an outer race disposed concentrically with each other and rotatable relative to each other, one of the races being fixed and the rotatable other race being adapted to bear against the rotatable member of a clutch device; a sleeve having a cylinder portion slidably fitted on a guide shaft; a connecting member holding the one race of the clutch release bearing for movement in the radial direction thereof relative to the sleeve; and a reinforcing plate disposed on the sleeve and adapted to contact with a yoke-like input member at two points when the input member pivotally moves; characterized in that the reinforcing plate is supported for movement to an extent exceeding 0.2 mm in a first direction which is a radial direction relative to the sleeve and is orthogonal to the pivot of the input member.

The clutch release bearing apparatus of the present invention is further characterized in that the reinforcing plate is movable also in a second direction which is a radial direction relative to the sleeve and differs from the first direction, but the amount of movement of the reinforcing plate in the second direction is smaller than the amount of movement thereof in the first direction.

The clutch release bearing apparatus of the present invention is further characterized in that the inner diameter surface of the reinforcing plate is guided by the cylinder portion of the sleeve.

According to the clutch release bearing apparatus of the present invention, the connecting member has the function of holding a bearing, and the reinforcing member has the function of receiving an input from the input member and can therefore receive an excessively great load from the input member while achieving the aligning function of the bearing. Also, the bearing holding member is provided with a projection and the connecting member is provided with a depression adapted to be engaged with the projection during the assembly thereof to thereby prevent the slipping-out of the connecting member and therefore, by the connecting member being assembled, the reinforcing member may be mounted between the bearing holding member and the base portion of the connecting member.

Also, according to the clutch release bearing apparatus of the present invention, the reinforcing member directly receives an input from the input member and a predetermined gap is provided in the axial direction between the connecting member and the reinforcing member and therefore, the force from the input member may be prevented from being transmitted from the reinforcing member to the connecting member, whereby the deformation or the like of the connecting member, etc. may be prevented.

Further, according to the clutch release bearing apparatus of the present invention, the bearing holding member has guide means for prescribing the axial direction position of the connecting member relative to one race of the bearing during the insertion of the 14 connecting member connecting member done by groping.

Furthermore, bearing apparatus reinforcing plate and therefore, the insertion of the can be easily effected even if it is according to the clutch release of the present invention, the against which the shift fork bears is supported for movement to a degree exceeding 0.2 mm in a first direction which is a radial direction relative to the sleeve and is orthogonal to the pivot of the shift fork and therefore, the reinforcing plate moves on the guide sleeve with the pivotal movement of the shift fork, whereby the amount of relative movement between the shift fork and the reinforcing plate can be decreased to thereby reduce wear. The reinforcing plate and the sleeve move relative to each other and therefore. wear may occur therebetween, but since the area of contact between the reinforcing plate and the sleeve is very large as compared with that between the shift fork and the reinforcing plate, the surface pressure between the reinforcing plate and the sleeve becomes very low and the wear, if any, is negligibly small.

On the other hand, the reinforcing plate can also be made movable in a second direction which is a radial direction relative to the sleeve and differs from the first direction. In such a case, if the amount of movement of the reinforcing plate in the second - 15 direction is made smaller than the amount of movement thereof in the first direction, the reinforcing plate will not move much in the second direction relative to the sleeve, whereby the reinforcing plate can be prevented from being shaken by an extraneous force such as vibration. If the shake of such a reinforcing plate is suppressed, a great load can be prevented from being transmitted to the sleeve, and even if the sleeve is made of resin, the deformation thereof can be sufficiently prevented.

Further, the inner diameter surface of the reinforcing plate can also be designed to be guided by the cylinder portion of the sleeve, whereby there is provided a construction which is simple and yet can sufficiently stand the load of the shift fork.

BRIEF DESCRIPTION OF THE DRAWINGS

Fig. 1 is a view of a clutch release bearing apparatus which is a first embodiment of the present invention as it is seen from a shift fork side; Fig. 2 is an axial cross-sectional view taken along the line II - II of Fig. 1; Fig. 3 is an enlarged perspective view of a spring member 30 in the first embodiment; Fig. 4 is a view showing a portion taken along the line IV - IV of Fig. 1 on an enlarged scale; Fig. 5 is a perspective view of a reinforcing 16 - member 40 in the first embodiment; Fig. 6 is a view of a clutch release bearing apparatus which is a second embodiment of the present invention as it is seen from a shift fork side; Fig. 7 is an axial cross-sectional view taken along the line VII - VII of Fig. 6; Fig. 8 is a view of a guide sleeve 120 in the second embodiment as it is seen in the same direction as in Fig. 6; Fig. 9 is a fragmentary enlarged view of the guide sleeve 120 as it is seen in the direction of arrow IX; Fig. 10 is an enlarged perspective view of a spring member 130 in the second embodiment; Fig. 11 is a perspective view of a reinforcing member 140 in the second embodiment; Fig. 12 is a view showing a portion taken along the line XII XII of Fig. 6 on an enlarged scale; Fig. 13 is a view of a clutch release bearing apparatus which is a third embodiment of the present invention as it is seen from a shift fork side; Fig. 14 is an axial cross-sectional view taken along the line XIV - XIV of Fig. 13; Fig. 15 is an enlarged perspective view of a spring member 230 in the third embodiment; Fig. 16 is an enlarged view of a portion of the embodiment of Fig. 14 which is indicated by XVI; Fig. 17 is a view similar to Fig. 16 but showing a 17 fourth embodiment of the present invention; Fig. 18 is a view of a clutch release bearing apparatus which is a fifth embodiment of the present invention as it is seen from the shift fork side; Fig. 19 is an axial cross-sectional view taken along the line XIX - XIX of Fig. 18; Fig. 20 is a perspective view of a reinforcing member 140 in the fifth embodiment; Fig. 21 is a graph showing a result obtained by the wear test of the clutch release bearing apparatus carried out under the conditions of a total stroke 100 million times and a release load 250 kgf, in which the wear depth of the reinforcing plate is represented by the axis of ordinates and the horizontal relative is movement amount between the reinforcing plate and the guide sleeve is represented by the axis of abscissas; Fig. 22 is a graph in which the peak value of a pedal stepping force is represented by the axis of ordinates and the horizontal (a first direction orthogonal to pivot of the shift fork) relative movement amount between the reinforcing plate and the guide sleeve is represented by the axis of abscissas; Fig. 23 is a view of a clutch release bearing apparatus which is a sixth embodiment of the present invention as it is seen from the shift fork side; Fig. 24 is a view showing a reinforcing plate alone taken out of Fig. 23; - 18 Fig. 25 is an axial cross-sectional view taken along the line XXV - XXV of Fig. 23; Fig. 26 is a view of a clutch release bearing apparatus which is a seventh embodiment of the present invention as it is seen in the same direction as in Fig. 25; Fig. 27 is a cross-sectional view showing a leaf spring according to the prior art with a flange portion on an enlarged scale and cut in the axial direction thereof; Fig. 28 is a cross-sectional view of a clutch release bearing apparatus according to the prior art;

Fig. 29 is an enlarged view of the vicinity of a spring member 130 in the clutch release bearing of Fig.

7; Fig. 30 is a cross-sectional view similar to Fig. 7, but showing a clutch release bearing according to another embodiment of the present invention; Fig. 31 is a fragmentary view of the clutch release bearing of Fig. 30 as it is seen in the direction of arrow XXX in Fig. 30; Fig. 32 is an enlarged view of attachment state of spring member 130 in the clutch release bearing depicted in Fig. 7; and Fig. 33 shows another example of the spring member 130.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Some embodiments of the present invention will hereinafter be described in detail with reference to the drawings.

Fig. 1 is a view of a clutch release bearing apparatus which is a first embodiment of the present invention as it is seen from a shift fork side. Fig. 2 is an axial cross-sectional view taken along the line II - II of Fig. 1.

Referring to Fig. 2, the clutch release apparatus comprises a clutch release bearing 10, a guide sleeve 20 which is a bearing holding member, and spring members 30 which are connecting members. The clutch release bearing 10 comprises a substantially tubular inner race 11 having a bearing portion lla at the left end thereof, a short tubular outer race 12 concentrically containing the inner race 11 therein, a plurality of balls disposed for rolling between the inner race 11 and the outer race 12, a retainer 16 retaining the balls 15 at predetermined intervals, and seals 17, 18 sealing the space defined by the inner race 11 and the outer race 12 on the axially opposite sides of. the balls 15, in a dustproof and oil-tight fashion. The inner race 11 is rotatably supported relative to the outer race 12. The bearing portion lla of the inner race 11 is of a radially outwardly turnedback shape, and is adapted to bear against the 20 is diaphragm spring of a clutch cover, not shown. Also, that end portion of the inner race 11 which is opposite to the bearing portion lla remains blank-worked by press and is not subjected to cutting work so as to keep the manufacturing cost low.

On the other hand, the guide sleeve 20 is made of resin and comprises a tubular body 21, a flange portion 22 extending radially from the outer periphery of the body 21 near the center thereof, an outer wall portion 23 protruding axially leftwardly at the radially outer end of the flange portion 22, and a guide portion 25 (Fig. 1) protruding axially at the radially outer end of the flange portion 22. A guide shaft, not shown, extends inwardly of the body 21, and the body 21 is slidable on the guide shaft. An enlarged diameter portion 24 is provided inwardly of the body 21. This enlarged diameter portion 24 functions so that the body 21 may not take in any foreign material when it slides on the guide shaft. The outer wall portion 23 is provided outwardly of the clutch release bearing 10 and provides a portion for limiting the radial movement thereof. Also, a gap 27 is formed between the outer periphery of the outer race 12 and the inner periphery of the outer wall portion 23 in order to make the clutch release bearing 10 radially movable. The guide portion 25 has the function of a guide during the assembly of the spring members 30, and axially extends on the opposite sides of the spring member 30.

As is apparent from Fig. 1, the two spring members 30 of the same shape have the function of attaching the clutch release bearing 10 to the guide sleeve 20. Fig. 3 is a perspective view of one of the spring members 30. Each of the spring members 30 is formed by stamping a spring steel plate such as SK5 (JIS G 4401) by press, and thereafter bending it, and then subjecting it to a hardening process. The spring member 30 comprises a base portion 31 bearing against the flange portion of the guide sleeve 20, a pressing portion 32 bearing against the outer race 12 of the bearing, and a beam portion 33 provided between the base portion 31 and the pressing portion 32 for imparting to the pressing portion 32 a resilient force for biasing the outer race 12. The pressing portion 32 has an inclined portion 32a axially outwardly inclined so as not to contact with the seal 17 and to facilitate the assembly of the spring member 30.

Further, the spring member 30 has a radial convex portion 34 formed in the portion of intersection between the base portion 31 and the beam portion 33 so as to protrude radially and fitted to the end portion of the flange portion 22 of the guide sleeve 20. Also, cut-aways 37 forming depressions are formed near the lower end on the opposite side portions 31a of the base 31, and relatively large cut-aways 38 are further formed in the lower edge portions 31b thereof. A chamfer 39 is formed an the portion of intersection between the cut-away 38 and the lower edge portion 31b. As shown in Fig. 33, the spring member 30 may have a curved concave portion with two or more local minimum width portions.

Fig. 4 is an enlarged view of the portion cut along the line IV - IV of Fig. 1 as it is seen in the direction of arrow. A projection 22c is further formed on the flange portion 22 of the guide sleeve 20. The projection 22c comprises an inclined surface 22d and a rest portion 22e, and is shaped so as to be engaged with the cut-away 37 when the spring member 30 is mounted.

Fig. 5 is a perspective view of a reinforcing member 40. The reinforcing member 40 comprises a cylinder portion 41, a plate-like anvil portion 42 protruding upwardly and downwardly from substantially the center of the cylinder portion 41, and a flange portion 43 extending radially from theend portion of the cylinder portion 41, and is formed by pressing a relatively thick sheet, and thereafter quenching it. Thereby, it is designed so as not to create remarkable wear in the portion of contact thereof with a shift fork.

The cylinder portion 41 has such a diameter that it just fits to the body 21 when it is mounted on the - 23 guide sleeve 20, whereby the radial positioning of the reinforcing member 40 may be accomplished. The upper and lower portions of the cylinder portion 41 are extended so as to correspond to the anvil portion 42, thereby forming rectangular portions 41a. These rectangular portions 41a have the function of guiding the shift fork and the function of securing the rigidity of the anvil portions.

As is apparent from Fig. 5, a level difference is formed between the anvil portion 42 and the flange portion 43. By this construction, a predetermined space 50 (Fig. 2) is created between the anvil portion 42 and the flange portion 22 of the guide sleeve 20 when the reinforcing member 40 is mounted on the guide sleeve 20. This space 50 can be utilized to insert a clip or the like when the shift fork is mounted on the clutch release bearing apparatus.

The flange portion 43 of the reinforcing member 40 is formed with a circular cut-away 43a in the circumferential portion thereof, and this cut-away 43a comes into engagement with a projection 22f formed at a location corresponding to the flange portion 22 of the guide sleeve 20 to thereby accomplish the detention of the guide sleeve 20. Further, the flange portion 43 is formed with an opening 43b for passing therethrough the projection 22c (Fig. 4) of the guide sleeve 20, and an opening 43c for passing therethrough the stopper 22g of the guide sleeve 20 which will be described later.

The flange portion 22 of the guide sleeve 20 i formed with a stopper 22g which is a rectangular projection near a projection 22c. As is apparent from Fig. 1, this stopper 22g is adapted to be engaged with the cut-away 38 of the spring member 30 when the spring member 30 is mounted on the guide sleeve 20, thereby preventing the spring member 30 from being pushed inwardly and further. The chamfer 39 of the spring member 30 has the function of facilitating the insertion thereof.

Description will now be made of the operation of a clutch release bearing apparatus which is a first embodiment of the present invention.

In Fig. 1, the shift fork, not shown, pivotally moves and the tip end thereof bears against the anvil portion 42 of the reinforcing member 40 and applies a predetermined load thereto. The plate thickness of the reinforcing member 40 is great and the rigidity thereof is sufficient and therefore, it can receive a great load from the shift fork. The clutch release bearing apparatus slides axially on a guide shaft, not shown, by the input from the shift fork and makes the bearing portion lla of the inner race 11 bear against the diaphragm spring of a clutch cover, not shown. Even when the diaphragm spring is rotating, the inner race 11 is rotatable and thus, after bearing, it rotates - 25 with the diaphragm spring and further, the bearing apparatus moves axially, whereby the diaphragm spring may be pressed and the clutch may be operated.

The spring member 30 has an appropriate plate thickness and supports the clutch release bearing 10 relative to the guide sleeve 20 by only a frictional force acting between the pressing portion 32 and the outer race 12 and therefore, the bearing 10 is radially movable relative to the guide sleeve 20. Thus, when the bearing portion lla of the inner race 11 bears against the diaphragm spring, if there is eccentricity between the two, there is created a known force which tends to position the bearing 10 concentrically, whereby the bearing 10 is radially moved and automatic aligning is accomplished. The outer wall portion 23 of the guide sleeve 20 has the function of limiting the movement of the bearing 10 so that the bearing 10 may not radially outwardly move by a predetermined amount or greater. Also, many of the outer races of ordinary ball bearings are of the type having no flange and therefore, if as in the present embodiment, the outer race is designed so as to be sandwiched by and between the spring members 30, it becomes unnecessary to reconstruct the outer race itself and the existing outer race can be used, and this can contribute to a reduction in cost.

Description will now be made of a method of assembling the clutch release bearing apparatus. The clutch release bearing 10 and the reinforcing member 40 are disposed around the body 21 of the guide sleeve 20, whereafter the spring members 30 are inserted obliquely downwardly and obliquely upwardly as viewed in Fig. 1 while being guided by the guide portion 25. The spring members 30 are made insertable from one direction around the outer periphery and are therefore easy to assemble. The spring members 30 ride over the projection 22c of the guide sleeve 20 while resiliently deforming the latter, and restore themselves to a predetermined shape when the cut-away 37 is engaged with the projection 22c and the cut-away 38 bears against the stopper 22g, and assembling is thus completed. The insertion of the spring members 30 is relatively easily effected by the action of the inclined surface 22d, but after engagement has once taken place, the spring members are designed so as not to slip out inadvertently owing to the action of the rest portion 22e.

In the present embodiment, the reinforcing member 40 is urged against the guide sleeve 20 with a predetermined biasing force by the spring members 30 and therefore, the reinforcing member 40 does not shake even when the diaphragm spring and the inner race 11 of the bearing do not bear against each other.

Fig. 6 is a view of a clutch release bearing - 27 apparatus which is a second embodiment of the present invention as it is seen from the shift fork side. Fig.

7 is an axial crosssectional view taken along the line VII - VII of Fig. 6.

Referring to Fig. 7, the clutch release apparatus, like the first embodiment, comprises a clutch release bearing 10, a guide sleeve 120 which is a bearing holding member, and spring members 130 which are connecting members. The construction of the clutch release bearing 10 is similar to that in the first embodiment and need not be described.

Also, the guide sleeve 120 is made of resin as in the first embodiment, and comprises a tubular body 21, a flange portion 122 extending radially from the outer periphery of the body 21 near the center thereof, an outer wall portion 23 protruding axially leftwardly at the radially outer end of the flange portion 122, and a guide portion 25 (Fig. 6) protruding axially at the radially outer end of the flange portion 122. A horizontal groove 126 is formed in the intermediate portion of the flange portion 122, and a clip (not shown).-for fixing a shift fork is adapted to be inserted into this horizontal groove 126.

Fig. 29 is an enlarged view of the vicinity of the spring member 130 in the clutch release bearing of Fig.

7, and the spring member when mounted is indicated by dotted lines, and the spring member when deformed is is indicated by solid lines. In Fig. 29, assuming that a radial force F is applied to the vicinity to the pressing portion 32 of the spring member 130, the spring member 130 receives a counter-clockwise moment and the pressing portion 32 tends to bend in a direction away from the outer race 12 of the bearing.

However, the gap Di between the inner surface (a first recess 30a) of a convex portion 34 and an outer projection 22h during mounting assumes an appropriate value and thus, in such a case, before the pressing portion 32 of the spring member 130 separates from the outer race 12 of the bearing, the inner surface of the convex portion 34 interferes with the outer projection 22h to thereby limit any further bending. Thereby, the pressing portion 32 is prevented from being spaced apart from the outer race 12, whereby the spring member is prevented from falling off.

Further, it is also possible to give Di a negative value, i.e., keeping the spring member contacting with the flange portion 122 before applying the radial force to the spring member.

In the clutch release bearing apparatus with the conventional structure, if the thickness of the outer ring is thin, the pressing portion of the spring member tends to fall off from the inner race of the outer ring even under the admitted eccentricity amount. If the entire circular surface of the inclined portion falls is off toward inside and the entire spring member become the same contacting condition to the outer ring, the outer ring is movable smoothly in any direction. The spring member, however, is designed not to interfere with the inner ring. Accordingly, the pressing portion opposite in 180 degrees to the portion at which the pressing portion is off from the outer ring, never falls off from the side surface of the outer ring. In this circumstance, the outer ring is not able to move in the direction with high resistance smoothly, i.e., the direction for opening the spring member, so that a sufficient alignment characteristic is no more expected.

In the present embodiment, a contacting angle a of the pressing portion 32 of the spring member 130 ranging 0 and 5 degrees is given to the pressing portion to the vertical direction in the assembled state of the spring member 130 as depicted in Fig. 32. In accordance with this arrangement, regardless of the radial direction of the movement of the outer ring 12, the inclined portion 32a cannot fall off toward the inner race side of the outer ring 12. Also, the arrangement gives small sectional height of the spring member, which provides freedom of the design for avoiding the interfere between the spring member 130 and inner ring 11. It should be noted that the contacting angle is preferably less than 5 degrees because excessively large contact angle may cause other problem.

Fig. 8 is a view of the guide sleeve 120 as it is seen in the same direction as Fig. 6, and Fig. 9 is a fragmentary enlarged view of the guide sleeve 120 of Fig. 8 as it is seen in the direction of arrow IX of Fig. 8. Referring to Fig. 8, a projection 122f is formed on the horizontal end portion of the flange portion 122 of the guide sleeve 120. Also, a stopper 22g formed at the mounted position of the spring member and a pair of projections 122c are formed on the flange portion 122. The substantially whole inner surface portion 22a of the flange portion 122 is lower than the periphery of the flange portion 122 in accordance with the plate thickness and shape of a reinforcing member 140 which will be described later, but the portion 122b thereof fitting to the spring member 130 is higher than that. Guide portions 25 have the function of a guide during the assembly of the spring member 130, and as shown in Fig. 9, they extend axially along the opposite sides of the spring member 130. In the other points, the construction of the guide sleeve is similar to that of the first embodiment and the same portions thereof as those in the first embodiment are given the same reference characters and need not be described.

As is apparent from Fig. 6, the two spring members of the same shape have the function of mounting the clutch release bearing 10 with respect to the guide sleeve 120. Fig. 10 is a perspective view of the spring member 130.

The spring member 130 has a convex portion 34 formed so as to protrude radially substantially between a base portion 131 and a beam portion 33, and this convex portion 34 corresponds to the end portion of the flange portion 122 of the guide sleeve 120. Also, cut aways 37 are formed near the lower ends of the opposite side portions 31a of the base portion 131, and relatively large cut-aways 38 are formed in the lower edge portions 31b thereof. Chamfers 39 are formed on the portions of intersection between the cut-aways 38 and the lower edge portions 31b. In the other points, the construction of the spring member is similar to that of the first embodiment and need not be described.

Fig. 11 is a perspective view of the reinforcing member 140. The reinforcing member 140, as in the first embodiment, comprises a cylinder portion 41, a plate-like anvil portion 42 protruding upwardly and downwardly from substantially the center of the cylinder portion 41, and a flange portion 43 extending radially from the end portion of the cylinder portion 41.

The flange portion 43 of the reinforcing member is formed with a rectangular cut-away 143a in the is circumferential portion thereof, and during mounting, this cut-away 143a comes into engagement with a projection 122f formed at a corresponding location on the flange portion 122 of the guide sleeve 120 to thereby accomplish the detention of the reinforcing member 140. Further, the flange portion 43 is formed with a C-shaped cut-away 143b for passing therethrough the projection 122c of the guide sleeve 120 and a stopper 22g. In the other points, the construction of the reinforcing member is similar to that of the first embodiment and need not be described.

Fig. 12 is an enlarged view taken along the line XII - XII of Fig. 6. The flange portion 122 of the guide sleeve 120 is further formed with a projection 122c. The projection 122c comprises an inclined surface 122d and a rest portion 122e, and is so shaped as to be engaged with the cut-away 37 when the spring member 130 is mounted. The level difference between the portion 22a (Fig. 8) and portion 122b of the flange portion 122 is greater than the plate thickness of the reinforcing member 140 and therefore, when the reinforcing member 140 is set there, a gap a may be created between the spring member 130 and the reinforcing member 140.

The operation of the clutch release bearing apparatus which is the second embodiment of the present invention is similar to that of the first embodiment.

Particularly, in the present embodiment, the spring member 130 and the reinforcing member 140 are spaced apart from each other so that the gap a may be created as shown in Fig. 12 and therefore, even when a force perpendicular to the axis is applied from the shift fork to the reinforcing member 140 with the clutch release operation, such force is not transmitted to the spring member 130. Thus, the spring member 130 is not deformed by the force from the shift fork.

A third embodiment of the present invention will now be described. This embodiment is characterized in that the guide sleeve which is a bearing holding member is provided with guide means to thereby easily effect the insertion of the spring members which are connecting means, and in the other points, the construction of this embodiment is similar to that of the first embodiment and therefore, the same portions of this embodiment as those of the first embodiment are given the same reference characters and need not be described.

Fig. 13 is a view of a clutch release bearing apparatus which is the third embodiment of the present invention as it is seen from the shift fork side. Fig. 14 is an axial cross-sectional view taken along the line XIV XIV of Fig. 13.

As is apparent from Fig. 13, two spring members 230 of the same shape have the function of mounting the clutch release bearing 10 with respect to a guide sleeve 220. Fig. 15 is a perspective view of the spring member 230.

The spring member 230 each have a recess 34a upwardly depressed in the lower surface of the center of a beam portion 33, and a convex portion 222h (Fig.

16) formed on the flange portion 22 of a guide sleeve 220 is adapted to be engaged with this recess 34a.

Fig. 16 is an enlarged view of a portion indicated by XVI in Fig. 14. Referring to Fig. 16, the flange portion 22 of the guide sleeve 220 is formed with a radially outwardly protruding convex portion 222h. The axial thickness of the convex portion 222h. is somewhat smaller than the axial width of the recess 34a of the spring member 230. The convex portion 222h, constitute guide means.

Description will now be made of a method of assembling the clutch release bearing apparatus. The clutch release bearing 10 and reinforcing member 40 are disposed around the body 21 of the guide sleeve 220, whereafter the spring members 230 are first inserted obliquely downwardly and obliquely upwardly as viewed in Fig. 13 while being guided by the guide portion 25 of the guide sleeve 220. The spring members 230 are made insertable from one direction of the outer periphery thereof and therefore are easy to assemble.

When each of the spring member 230 is inserted to - about the middle, the recess 34a of the spring member 230 comes into engagement with the convex portion 222h of the guide sleeve 220, as shown in Fig. 16. Thereafter, the spring member 230 is further inserted inwardly while being guided by the convex portion 222h. According to such a construction, during the insertion of the spring member 230, it is guided by the convex portion 222h and therefore, the axial positioning thereof is done, whereby any axial deviation of the inclined portion 32a of the spring member 230 relative to the outer race 12 can be prevented. Thus, even if the axial length C of the inclined portion 32a is made relatively small, smooth insertion of the spring member 230 is possible. The construction of the present embodiment is particularly effective under a dimensionally limited condition under which there is the possibility of the interference between the inclined portion 32a and the inner race of the bearing.

In order to secure smoother insertion, in the embodiment of Fig. 16, there is established the relation that h < H between the dimensions of the respective portions. The convex portion 222h also has the function of preventing the spring member 230 from axially falling down after the insertion of the spring member 230.

Also, it is difficult owing to the convex portion 222h of the guide sleeve 220 for the spring member 230 to fall down axially after engaged with the projection 22c of the guide sleeve 220.

The reinforcing member 40 is also urged against the guide sleeve 220 with a predetermined biasing force by the spring members 230 and therefore, the reinforcing member 40 does not shake even when the diaphragm spring and the inner race 11 of the bearing do not bear against each other.

Fig. 17 is a view similar to Fig. 16, but showing a fourth embodiment of the present invention. The fourth embodiment of Fig. 17 differs in the shape of the flange portion 322 of the guide sleeve from the third embodiment of Fig. 16. The flange portion 322, as in the embodiment of Fig. 16, is formed with a convex portion 322h, but this convex portion 322h constitutes first guide means for spring members 330. That is, the convex portion 322h accomplishes axial positioning to a certain degree when each spring member 330 is inserted to about the middle. On the other hand, what constitute second guide means is a visor portion 322j axially extending somewhat shorter than the outer race 12 from the end portion of the flange portion 322.

According to the fourth embodiment of Fig. 17, when the spring member 330 has been inserted to about the middle, the axial portion of the spring member 330 is regulated to a certain degree by the convex portion 322h and therefore, the inclined portion 32a of the spring member 330 is adapted to bear against just the outer portion of the tip end of the visor portion 322j. Also, the tip end of the visor portion 322j is axially somewhat shorter than the outer race 12, and the inclined portion 32a is adapted to bear against the outer portion of the end portion of the outer race 12 when the pressing portion 32 of the spring member 330 is inserted while being guided by the tip end of the visor portion 322j. Thus, smooth insertion of the spring members 330 is possible even if the axial length C of the inclined portion 32a. is made relatively small. According to such a construction, the relation that h < H between the dimensions of the respective portions as shown in Fig. 16 becomes unnecessary.

Fig. 18 is a view of a clutch release bearing apparatus which is a fifth embodiment of the present invention as it is seen from the shift fork (indicated by a phantom line) side. Fig. 19 is an axial crosssectional view taken along the line XIX - XIX of Fig. 18.

Referring to Fig. 19, the clutch release bearing apparatus, like the first and second embodiments, comprises a clutch release bearing 10, a guide sleeve 120 which is a bearing holding member, and spring members 130 which are connecting members. The construction of the clutch release bearing 10 is similar to that of the above-described embodiments and need not be described.

Also, the guide sleeve 120 is made of molded resin, and as in the second embodiment it comprises a tubular body 21, a flange portion 122 extending radially from the outer periphery of the body 21 near the center thereof, an outer wall portion 23 protruding axially leftwardly at the radially outer end of the flange portion 122, and a guide portion 25 (Fig. 18) protruding axially at the radially outer end of the flange portion 122.

The construction of the guide sleeve 120 is similar to that of the second embodiment, and the same portions thereof as those of the second embodiment are given the same reference characters and need not be described.

In the present embodiment, the gate position during the molding of resin is set to a position indicated by arrow D in Fig. 19. Consequently, a weld plane WP is at a position indicated by a dotted line in Fig. 18 which deviates by 180' from the position D. The gate position may also be a position indicated by arrow E, F or G.

Fig. 20 is a perspective view of a reinforcing member 140. The reinforcing member 140 also is similar in construction to that in the second embodiment and need not be described.

is In the reinforcing plate 140, the cross-hatched portion in Fig. 20 is a portion which originally bears against the corresponding portion of the guide sleeve 120 and takes charge of positioning, but in the present embodiment, it is formed while being inwardly depressed so as to become movable with a gap A (Fig. 18) in a horizontal direction (a first direction orthogonal to the pivot of the shift fork) when it is fitted to the guide sleeve 120. On the other hand, the reinforcing plate 140 is fitted to the projection 122f of the guide sleeve 120 in a vertical direction (a second direction) with a gap 6 smaller than the gap A in the horizontal direction. In the present embodiment, A = 0.15 mm.

The operation of the clutch release bearing apparatus which is the fifth embodiment of the present invention is similar to that of the first and second embodiment.

In Fig. 18, the shift fork indicated by a phantom line pivotally moves about a vertically extending pivot Px and the tip end thereof bears at two points against a point Ps (Fig. 18) on the anvil portion 42 of the reinforcing member 140 and applies a predetermined load thereto.. Thus, such point Ps moves in a horizontal direction with the pivotal movement of the shift fork. The position of the weld plane (weld portion) WP is disposed on a line linking the two bearing points (input points) Ps of the shift fork together as viewed in the axial direction and therefore, the distance of the cross-section receiving a moment load from the center axis of the figure becomes substantially zero and thus, the stress by the moment load can be minimized.

The spring members 130 each have an appropriate plate thickness and support the clutch release bearing 10 relative to the guide sleeve 120 by only a frictional force acting between the pressing portion 32 and the outer race 12 and therefore, the bearing 10 is radially movable relative to the guide sleeve 120. This frictional force is somewhat greater than this load so that the clutch release bearing may not be moved by a vibration acceleration acting on the clutch release bearing and moreover, is adjusted to such a slight value that during eccentricity, the bearing is movable to effect automatic aligning, and is usually of the order of 5 to 15 kgf. Thus, when the bearing portion lla of the inner race 11 bears against the diaphragm spring, if there is eccentricity between the two, there is created a known force which tends to position the bearing 10 concentrically, whereby the bearing 10 is radially moved and automatic aligning is accomplished.

The guide sleeve 120 and the reinforcing member 140 are movable relative to each other in a direction orthogonal to the pivot Px of the shift fork, i.e., a - 41 horizontal direction, within the range of the gap 2.A (0.3 mm) as shown in Fig. 18 and therefore, when from the shift fork pivotally moving with the clutch release operation, a force perpendicular to the axis and in a horizontal direction is applied to the reinforcing member 140, the reinforcing member 140 can also move in a horizontal direction, whereby the wear of the shift fork and the bearing portion of the reinforcing plate can be reduced. On the other hand, the guide sleeve 120 and the reinforcing member 140 are mounted in a vertical direction with a gap smaller than the gap in the horizontal direction and therefore, even if the vibration or the like of a vehicle is transmitted thereto, the shake of the reinforcing member 140 is suppressed, whereby unnecessary wear and abnormal sound can be prevented.

As regards the gap between the guide sleeve and the reinforcing member, it is necessary to provide a gap A in each portion so that the reinforcing member may be movable in the horizontal direction, but the location of the smallest gap is loaded with a force of the horizontal component of the frictional force of the shift fork and therefore, it is necessary to design with the strength of the reinforcing member taken into account. For instance, in the embodiment of Fig. 18, there will be provided a design having sufficient strength in term of structure if the gap between the 42 outer periphery of the cylinder of the guide sleeve and the inner periphery of the cylinder of the reinforcing member is made smallest.

Fig. 21 is a graph showing a result obtained from the wear test of the clutch release bearing apparatus carried out under the conditions of a total stroke 1,000,000 times and a release load 250 kgf, and the wear depth of the reinforcing plate is represented as the axis of ordinates and the horizontal relative movement amount between the reinforcing plate and the guide sleeve is represented as the axis of abscissas. From Fig. 21, it is seen that the wear depth of the reinforcing plate sharply decreases when the relative movement amount between the reinforcing plate and the is guide sleeve exceeds 0.2 mm.

On the other hand, Fig. 22 is a graph in which the peak value of the pedal stepping force is represented as the axis of ordinates and the horizontal relative movement amount between the reinforcing plate and the guide sleeve is represented as the axis of abscissas. From Fig. 22, it is understood that the peak value of the pedal stepping force becomes low if design is made such that the relative movement amount between the reinforcing plate and the guide sleeve exceeds 0.2 mm.

A sixth embodiment of the present invention will now be described with respect chiefly to the differences thereof from the fifth embodiment.

43 - Fig. 23 is a view of a clutch release bearing apparatus which is the sixth embodiment as it is seen from the shift fork side. Fig. 24 is a view of only a reinforcing plate 440 taken out from Fig. 23.

Fig. 25 is an axial cross-sectional view taken along the line XXV - XXV of Fig. 23. The differences of the present embodiment from the above-described fifth embodiment will be chiefly described hereinafter.

A yoke portion 425 comprises a body 425a extending from a flange portion 422 to the shift fork side, a projected portion 425b radially inwardly extending from the tip end thereof, and a rib-like stay 425c formed so as to surround the outer portion of the root of the yoke portion 425. When the shift fork, not shown, is once positioned inwardly of the yoke portion425, the shift fork and a guide sleeve 420 may be moved together by the action of the projected portion 425b. Again in the present embodiment, the gate position is set to a position indicated by arrow D in Fig. 25.

Consequently, the weld plane WP is at a position indicated by a dotted line in Fig. 23 which deviates by therefrom. The gate position may also be a position indicated by arrow E, F, G or J.

The yoke portion 425 is molded integrally with the guide sleeve 420. To improve the rigidity and strength of the yoke portion 425, there is also an idea that it will suffice if the thickness of the root of the yoke 44 portion 425 is simply increased. However, if the thickness of a portion of the yoke portion 425 is increased, the non-uniformity of the contraction of the blank may result during molding and as a result, a void may be created in the thick portion to thereby reduce the quality of the product. So, the stay 425c is made into a rib-like shape having substantially the same width as the thickness of the yoke portion 425 so that a void or the like may be avoided with the contraction during molding taken into account. The stay 425c constitutes a reinforcing portion. In Fig. 23, triangular plate-like ribs 420a and 420b are provided so as to connect a cylinder portion and the flange portion 422 together. The ribs are provided in regions wherein a moment created between the cylinder portion and the flange portion 422 by an input received from the shift fork becomes greatest, thereby achieving an improvement in the strength of the guide sleeve 420.

In Fig. 24, such a dimension and shape that there is no gap when a reinforcing plate 440 fits to the guide sleeve 420 are indicated by dotted lines. That is, the reinforcing plate 440, as is apparent from Fig.

24, is formed while being depressed inwardly from a dotted-line position to a solid-line position so as to be movable with a gap A (Fig. 23) in a horizontal direction when it is fitted to the guide sleeve 420.

Also, in a vertical direction, it is fitted with a gap 6 smaller than the gap A in the horizontal direction.

Description will now be made of the operation of the clutch release bearing apparatus which is the sixth embodiment of the present invention.

The shift fork, not shown, pivotally moves and the tip end thereof bears against the reinforcing member 440 to thereby apply a predetermined load thereto. The plate thickness of the reinforcing member 440 is relatively great and the rigidity thereof is sufficient and therefore, the reinforcing member can receive a great load from the shift fork. The clutch release bearing apparatus is axially slidden on a guide shaft, not shown, by an input from the shift fork to thereby cause the bearing portion lla of the inner race 11 to bear against the diaphragm spring of a clutch cover, not shown. Even if the diaphragm spring is rotating, the inner race 11 is rotatable and thus, it rotates with the diaphragm spring after it bears against the latter, and the bearing apparatus is further moved, whereby the diaphragm spring may be pressed and the clutch may be operated.

The shift fork pivotally moves in a horizontal plane and therefore, structurally the yoke portion 425 ought not to receive a radial force from the shift fork, but actually it sometimes receive a great force due to the vibration from an engine and the shake of parts. Even when the yoke portion receives such a - 46 force, it can sufficiently resist this force because the stay 425c is formed on the root of the yoke portion 425.

The guide sleeve 420 and the reinforcing member 440 are movable relative to each other in a horizontal direction within the range of a gap 2.A as shown in Fig. 23 and therefore, when a force in a direction perpendicular to the axis (a horizontal direction) is applied to the reinforcing member 440 from the shift fork pivotally moving with the clutch release operation, the reinforcing member 440 is horizontally moved, whereby the wear of the shift fork and the bearing portion of the reinforcing plate can be reduced. On the other hand, the guide sleeve 420 and the reinforcing member 440 are mounted in a vertical direction with a gap smaller than the gap in the horizontal direction and therefore, even if the vibration or the like of the vehicle is transmitted to them, the shake of the reinforcing member 440 is suppressed, whereby unnecessary wear, abnormal sound, etc. can be prevented.

A seventh embodiment of the present invention will now be described with respect chiefly to the differences thereof from the above-described embodiments.

Fig. 26 is a view of a clutch release bearing apparatus which is the seventh embodiment as it is seen in the same direction as in Fig. 25. The differences of the present embodiment from the above-described embodiments will be chiefly described hereinafter.

Referring to Fig. 26, a reinforcing plate 540 is mounted at the right of a flange portion 522 extending radially from a guide sleeve 520 made of resin. One end of a cylindrical case 550 is mounted on the outer end of the flange portion 522 by caulking. The other end of the case 550 holds a bearing 510 through a wavy spring 560. The wavy spring 560 urges the bearing 510 against the case 550 with a predetermined biasing force, but is adapted to permit the movement thereof in a radial direction.

In Fig. 26, the vertical gap between the reinforcing plate 540 and the guide sleeve 520 is 5 (0.05 mm). On the other hand, although not shown, the horizontal gap between the two is A (0.15 mm) as in the abovedescribed embodiments. In the present embodiment, the horizontal gap is greater than the vertical gap and therefore, 6 < A is established.

In the fifth and sixth embodiments, the reinfo-rcing plate is movable also in a second direction which is a radial direction relative to the sleeve and which differs from a first direction, but the movement amount of the reinforcing plate in the second direction is smaller than the movement amount thereof in the first direction and therefore, the reinforcing plate does not move much in the second direction relative to the sleeve, whereby the reinforcing plate is prevented from being shaken by an extraneous force such as vibration. If the shake of such a reinforcing plate is suppressed, a great load can be prevented from being transmitted to the sleeve, and even if the sleeve is made of resin, the deformation thereof can be prevented.

Further, the inner diameter surface of the reinforcing plate is guided by the cylinder portion of the sleeve and therefore, the reinforcing plate is simple in construction, and yet can sufficiently stand the load of the shift fork.

While the present invention has been described is above with respect to some embodiments thereof, the present invention is not restricted to the abovedescribed embodiments, but of course, changes and improvements are suitably possible. For example, the number of the spring members need not always be two, but may be three. Further, the construction of the present invention will become possible even if the rotatable race is not the inner race but the outer race.

As described above, according to the clutch release apparatus of the present invention, the connecting member is designed to have the function of holding the bearing and the reinforcing member is 49 - designed to have the function of receiving the input from the input member and therefore, the apparatus can achieve the function of aligning the bearing and yet can receive the excessively great load from the input member. Also, the bearing holding member is provided with a projection and the connecting member is provided with a depression adapted to be engaged with the projection during assembly to thereby prevent the slipping-out of the connecting member and therefore, by the connecting member being assembled, the reinforcing member is adapted to be mounted while being held between the bearing holding member and the base portion of the connecting member.

Also, according to the clutch release apparatus of is the present invention, the reinforcing member receives an input directly from the input member and also, a predetermined gap is provided in the axial direction between the connecting member and the reinforcing member and therefore, the force from the input member is prevented from being transmitted from the reinforcing member to the connecting member, whereby the deformation or the like of the connecting member, etc. may be prevented.

Also, according to the clutch release apparatus of the present invention, the bearing holding member has guide means for prescribing the axial position of the connecting member relative to one race of the bearing so during the insertion of the connecting member and therefore, even if the insertion is done by groping, the insertion of the connecting member can be accomplished easily.

Also, according to the clutch release bearing apparatus of the present invention, the reinforcing plate against which the shift fork bears is supported for movement to an extent exceeding 0.2 mm in the first direction which is the radial direction relative to the sleeve and is orthogonal to the pivot of the shift fork and therefore, with the pivotal movement of the shift fork, the reinforcing plate moves on the guide sleeve, whereby the relative movement amount between the shift fork and the reinforcing plate can be reduced to thereby reduce the wear thereof. The reinforcing plate and the sleeve move relative to each other and therefore, wear may occur therebetween, but the area of contact between the reinforcing plate and the sleeve is very large as compared with that between the shift fork and the reinforcing plate and therefore, the surface pressure between the reinforcing plate and the sleeve becomes very small and the wear, if any, is negligibly small. That is, according to the present invention, any increase in wear resistance on the surface of contact between the shift fork and the reinforcing plate and the catch of the shift fork can be prevented to thereby smooth the operation of the clutch and also 51 prevent any increase in the peak value of the release load.

Fig. 30 is a cross-sectional view similar to Fig. 7, but showing a clutch release bearing according to another embodiment of the present invention. Fig. 31 is a fragmentary view of the clutch release bearing of Fig. 30 as it is seen in the direction of arrow X=. The embodiment of Figs. 30 and 31 is substantially similar to the embodiment of Fig. 7, but somewhat differs in the shape of a reinforcing member 640 and the shape of a spring member 730 from the embodiment of Fig. 7. More specifically, the outer peripheral portion 640b of the reinforcing member 640 protrudes outwardly and two projections 640a formed by press are provided on that surface thereof which is adjacent to the shift fork, and on the other hand, the spring member 730 is formed with only cut-aways 730a in a portion corresponding thereto. The projections 640a are formed by the reinforcing member being pushed from its back by a pointed tool and is of a shape rising radially inwardly. In the present embodiment, bearing holding means is constituted by the guide sleeve 20 and the reinforcing member 640, and an outwardly extending portion is constituted by the projections 640a.

When the spring member 730 is inserted into the reinforcing member 640, the spring member 730 rides over the projections 640a while resiliently deforming 52 - is the latter, and when the cut-aways 730a come into engagement with the projections 640a, the spring member is restored to a predetermined shape, thus completing assembly. Due to the shape of the projections 640a, the insertion of the spring member 730 is accomplished relatively easily, but the spring member is designed such that it does not inadvertently slip out after it has once been engaged.

On the other hand, assuming that a radial force is applied to the vicinity of the pressing portion 732 of the spring member 730, the spring member 730 receives a counter-clockwise moment and the pressing portion 732 tries to bend in a direction away from the outer race 12 of the bearing. However, the gap Di between the inner surface of a convex portion 734 and the outer peripheral portion 640b during mounting assumes an appropriate value and therefore, in such a case, the outer peripheral portion 640b interferes with the spring member 730 to thereby limit any further bending before the pressing portion 732 of the spring member 730 comes off the outer race 12 of the bearing. Thus, the pressing portion 732 is prevented from becoming spaced apart from the outer race 12, thereby preventing the spring member 730 from falling off.

Claims (15)

1. CLAIMS: 1. A clutch release bearing apparatus comprising a clutch release

   bearing including an inner race and an outer race disposed concentrically with each other and rotatable relative to each other, one of the races being fixed and the rotatable other race being adapted to bear against the rotatable member of a clutch device; a bearing holding member made of resin and provided with a cylinder portion slidably fitted on a guide shaft, and a flange portion; and a connecting member holding said one race of said clutch release bearing for movement in the radial direction thereof relative to said bearing holding member; wherein said connecting member is deformed by assembly, whereby a pressing portion biases said one race toward said bearing holding member, provision is further made of a reinforcing member interposed between an input member and said bearing holding member for receiving an input from said input member---and transmitting it to the flange portion of said bearing holding member, said bearing holding member is provided with a projection, said connecting member is provided with a depression adapted to be engaged with said projection during the assembly thereof to thereby prevent the 54 slipping-out of said connecting member, and by said connecting member being assembled, said reinforcing member is adapted to be mounted between said bearing holding member and said connecting member.
2. 2. A clutch release bearing apparatus according to Claim 1, wherein a gap is provided in the axial direction between said connecting member and said reinforcing member.
3. 3. A clutch release bearing apparatus according to Claim 1, wherein the flange portion of the bearing holding member is formed with a horizontal groove into which a clip for fixing a shift fork is inserted.
4. 4. A clutch release bearing apparatus according to Claim 1, wherein said connecting member is inserted from the radial direction relative to said clutch release bearing and said bearing holding member during assembly, and is adapted to hold said one race and said bearing holding member in the axial direction when it arrives at a predetermined position, and said bearing holding member further has guide means for prescribing the axial position of said connecting member relative to said one race during the assembly of said connecting member.

   -
5. 5. A clutch release bearing apparatus according to Claim 1, wherein said reinforcing member is supported for movement to an extent exceeding 0.2 mm in a first direction which is a radial direction relative to said bearing holding member and is orthogonal to the pivot of said input member.
6. 6. A clutch release bearing apparatus according to Claim 5, wherein said reinforcing member is movable also in a second direction which is a radial direction relative to said bearing holding member and differs from said first direction, but the amount of movement of said reinforcing member in said second direction is smaller than the amount of movement thereof in said first direction.
7. 7. A clutch release bearing apparatus according to Claim 5, wherein the inner diameter surface of said reinforcing member is guided by the cylinder portion of said bearing holding member.
8. 8_. A clutch release bearing apparatus comprising a clutch release bearing including an inner race and an outer race disposed concentrically with each other and rotatable relative to each other, one of the races being fixed and the rotatable other race being adapted to bear against the rotatable member of a - 56 clutch device; a sleeve having a cylinder portion slidably fitted on a guide shaft; a connecting member holding said one race of said clutch release bearing for movement in the radial direction thereof relative to said sleeve; and a reinforcing plate disposed on said sleeve and adapted to contact with a yoke-like input member at two points when said input member pivotally moves; said reinforcing plate being supported for movement to an extent exceeding 0.2 mm in a first direction which is a radial direction relative to said sleeve and is orthogonal to the pivot of said input member.
9. 9. A clutch release bearing apparatus according to Claim 8, wherein said reinforcing plate is movable also in a second direction which is a radial direction relative to said sleeve and differs from said first direction, but the amount of movement of said reinforcing plate in said second direction is smaller than the amount of movement thereof in said first direction.
10. 10. A clutch release bearing apparatus according to Claim 8, wherein the inner diameter surface of said reinforcing plate is guided by the cylinder portion of 57 said sleeve.

    is
11. 11. A clutch release bearing apparatus comprising: a clutch release bearing including an inner race and an outer race disposed concentrically with each other and rotatable relative to each other, one of the races being fixed and the rotatable other race being adapted to bear against the rotatable member of a clutch device; a bearing holding means provided with a cylinder portion slidably fitted on a guide shaft, and an outwardly extending portion; and a connecting member holding said one race of said clutch release bearing for movement in a radial direction relative to said bearing holding means; wherein said connecting member has concave portion having two or more different widths in the axial direction thereof, one end portion of said connecting member is engaged with said outwardly extending portion, and the other end portion of said connecting member is adapted to be engaged with the stationary race of said clutch release bearing and apply a pressing force in a direction in which said outwardly extending portion and said stationary race come close to each other, and when a force is applied in a radial direction to that end portion of said connecting member which is adjacent to the stationary race, said connecting member is inclined before said end portion comes off said stationary race to limit the inclination of said connecting member.
12. 12. A clutch release bearing apparatus according to Claim 11, wherein, when a force is applied in a radial direction to that end portion of said connecting member which is adjacent to the stationary race, said connecting member is inclined, whereby before said end portion comes off said stationary race, one of said concave portion comes into contact with said outwardly extending portion, whereby the inclination of said is connecting member is limited.
13. 13. A clutch release bearing apparatus comprising:

    a clutch release bearing including an inner race and an outer race disposed concentrically with each other and rotatable relative to each other, one of the races being fixed and the rotatable other race being adapted to bear against the rotatable member of a clutch device; a bearing holding means provided with a cylinder portion slidably fitted on a guide shaft, and an outwardly extending portion; and - 59 a connecting member holding said one race of said clutch release bearing for movement in a radial direction relative to said bearing holding means; wherein one end portion of said connecting member is engaged with said outwardly extending portion, and the other end portion of said connecting member is adapted to be engaged with the stationary race of said clutch release bearing and apply a pressing force in a direction in which said outwardly extending portion and said stationary race come close to each other, and, in an assembled state of said connecting member, an angle of a pressing portion of said connecting member falls within zero and five degrees to vertical direction.
14. 14. A clutch release bearing apparatus according to Claim 1, wherein said bearing holding member includes a couple of yoke portion elongating from the outer periphery of the flange portion in the axial direction to guide said input member, and rib-like reinforcing portion is formed near a root of said yoke portion.
15. 15. A clutch release bearing apparatus according to Claim 11, wherein said connecting member is in contact with the clutch release bearing side of said outwardly extending portion before applying the radial force to the connecting member in the assembled state of said connecting member.