Clutch cover assembly with retaining lugs for the pressure plate

A clutch cover assembly is disclosed in which the cover has radial retaining lugs which cooperate with transverse shoulders on the pressure plate for limiting the axial travel relative to the cover. Slots which may receive the lugs are provided in the pressure plate and may comprise one or more axial and/or circumferential grooves in continuity with the transverse shoulders. The grooves may be formed in the peripheral edge of the main body of the pressure plate or in the axial bosses engageable with the axially acting spring or in radial bosses at the edge of the pressure plate.

BACKGROUND OF THE INVENTION 
The present invention relates generally to automotive friction clutches, 
and more particularly to clutch cover assemblies which comprise a unitary 
assembly which is mounted on a reaction plate or flywheel after the 
insertion of a friction plate or driven disc therebetween to make up the 
clutch. 
Generally speaking, such a clutch cover assembly comprises a plurality of 
generally annular members including a cover, a pressure plate connected 
for rotation with the cover by attachment means permitting limited axial 
displacement of the pressure plate relative to the cover. The cover 
assembly further comprises between the cover and the pressure plate 
axially acting resilient means bearing against the cover and applied 
against the pressure plate to urge the pressure plate axially away from 
the cover. 
The present invention relates more particularly to the case where between 
the cover and the pressure plate are provided abutment means for axially 
retaining the pressure plate after predetermined axial travel relative to 
the cover. Indeed, it has been established that in at least certain 
applications it is desirable to limit the axial travel of the pressure 
plate against the axially acting resilient means. This is especially true 
when the attachment means attaching the pressure plate to the cover not 
only have the function of transmitting torque between the cover and the 
pressure plate while permitting axial displacement of the pressure plate 
relative to the cover, but also when they ensure the function of 
resiliently urging the pressure plate away from the associated clutch 
plate for clutch disengagement. 
As is known the attachment means are usually formed by spring steel straps 
which are disposed generally transversely relative to the axis of the 
assembly or generally radially, and have a rather low axial stiffness. 
Moreover, when cover assembly is unloaded, i.e., before mounting on the 
reaction plate or when handling the cover assembly on its own, the straps 
may be deformed to the detriment to their service life and/or 
effectiveness if measures are not taken to limit the axial displacement of 
the pressure plate relative to the cover under the action of the axially 
acting resilient means on the pressure plate, the latter not being in 
axial abutment. 
In practice, when the axially acting resilient means comprise a diaphragm 
spring having a Belleville washer peripheral portion and a central portion 
divided into radial fingers for controlling the release of the peripheral 
portion, it is usual to provide along the inner periphery of the cover 
radial tabs. The radial fingers of the diaphragm spring come to bear 
against the inner periphery of the tabs on the cover which limits the 
resilient force applied to the pressure plate by the diaphragm and 
therefore the axial displacement of the pressure plate relative to the 
cover. 
Yet, but in this situation, in the course of a handling the cover assembly 
without any particular precautions in its unloaded condition, owing to its 
substantial weight the pressure plate may be caused to swing sufficiently 
from the cover to cause a latent defect or damage to the straps attaching 
the pressure plate to the cover. 
Consequently, it is common to provide with the pressure plate abutment 
means to ensure positive axial retention of the pressure plate to prevent 
axial displacement beyond a predetermined distance from the cover. 
In French patent application No. 2,437,525, the retaining means provided 
for this purpose comprise retaining lugs formed from the cover, and a 
transverse shoulder on the pressure plate is adapted to abutment against 
each retaining lug. In this French patent publication for cooperation with 
the transverse shoulder formed by the outer surface of the pressure plate 
directed outwardly relative to the lateral wall of the cover, the 
retaining lugs extend circumferentially. Each of the retaining lugs is 
formed by a strike or cutout in the lateral part of the notches usually 
provided in such a cover for radial lugs on the pressure plate required 
for fixing to the pressure plate the straps connecting it to the cover. 
The circumferentially extension of these retaining lugs has various 
drawbacks. First of all, there is necessarily a predetermined single 
direction of rotation depending on the direction of the extension of the 
retaining lugs whereby the cover assembly can only be used for a single 
direction of rotation. This direction of rotation corresponds to the 
straps operating in traction. For cover assemblies having a given 
direction of rotation covers must be used with retaining lugs extending 
circumferentially in the corresponding direction. 
Further, the cutouts in the lateral part of the notches in the cover for 
the formation of the retaining lugs necessarily substantially locally 
weakens the cover. 
Finally, the presence of such circumferential retaining lugs makes it is 
difficult to effect axial abutment in both directions of the pressure 
plate in order to protect the bending of the straps attaching the pressure 
plate to the cover, and/or circumferential abutment of the pressure plate 
to avoid straps buckling. 
In DOS No. 2,906,863, the retaining lugs are formed from the cover for 
cooperation with the radially extending transverse shoulder on the 
pressure plate, but the pressure plate has on its inner periphery a 
transverse shoulder which at least in this embodiment is in continuity 
with a slot in the pressure plate. 
There is a resulting relatively large radial distance between the 
circumference of the pressure plate on which the retaining lugs are 
disposed and the circumference of the pressure plate corresponding to the 
position at which the axially acting resilient means bear. The consequent 
lack of alignment makes the operation of the retaining lugs rather 
uncertain. 
SUMMARY OF THE INVENTION 
An object of the present invention is the provision of an arrangement which 
permits the foregoing drawbacks to be substantially diminished or overcome 
as well as providing other advantages. 
The invention provides a clutch cover assembly for a motor vehicle of the 
type comprising a cover, a pressure plate connected for rotation with the 
cover by attachment means permitting limited axial displacement of the 
pressure plate relative to the cover. Axially acting resilient means 
bearing against the cover and applied against the pressure plate urge the 
pressure plate axially away from the cover. Abutment means axially retain 
the pressure plate after predetermined axial travel of the pressure plate 
relative to the cover. The retaining means comprises at least one radial 
retaining lug on the cover and a transverse shoulder on the pressure plate 
cooperable with the retaining lug, the shoulder extending in continuity 
with a slot in the pressure plate. The clutch cover assembly is 
characterized by the slot being provided along the outer peripheral edge 
of the pressure plate, whereby the axial abutment of the pressure plate 
with the retaining lug is situated along a circumference proximate to that 
of the circumference along which said axially acting resilient means is 
applied. 
The term "outer peripheral edge of the pressure plate" designates in the 
present application the entire periphery of the pressure plate between the 
outer transverse surface of the pressure plate and the contact zone of the 
pressure plate with the axially acting resilient means. 
In any event, with the arrangement according to the invention the lack of 
alignment or registration between the retaining lug on the cover and the 
axially acting resilient means is advantageously minimized, or even 
entirely eliminated, which contributes to better retention of the pressure 
plate. Moreover, with such an arrangement it is advantageously possible to 
utilize a single cover which is suitable for clutches rotating in either 
direction which obviously favors cost-saving standardization of parts. 
Furthermore, since the retaining lug on the cover extends radially, it may 
be very simply formed from the lateral cylindrical or generally 
frustoconical part of the cover, which is usually eliminated for the 
formation of ventilation openings for ventilating the interior of the 
cover, and therefore without an additional or particular weakening of the 
cover. 
In addition, the slot or slots provided according to the invention 
advantageously not insubstantially lighten the pressure plate and 
therefore reduce the moment of inertia without detriment to rigidity. 
Moreover, at least for some embodiments the radial retention of the 
pressure plate is made possible by abutment at the end of the slot or 
slots at the end of the retaining lug or lugs on the cover. 
Finally, for at least some embodiments in which such a slot or slots 
comprise an axial groove opening axially on the outer surface of the 
pressure plate, facing away from the cover, which is the face of the 
pressure plate cooperating with the clutch plate, such a slot or slots may 
contribute to eliminating dust which may develop thereon owing to the 
inevitable wear of the friction facings of the clutch plate in the course 
of use. 
These and other features and advantages of the invention will be brought in 
the description which follows, given by way of example, with reference to 
the accompanying diagrammatic drawings.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
Generally speaking, and as illustrated in the drawings the cover assembly 
comprises a series of annular parts including a cover 10, a pressure plate 
with axially acting resilient means formed as a diaphragm spring 33 
described in detail hereinbelow, bearing against the cover 10 and urging 
the pressure plate 11 axially away from the cover. 
As diagrammatically illustrated in phantom lines in FIGS. 2 and 3, the 
clutch cover assembly is adapted to be mounted by screws (not shown) on a 
reaction plate or flywheel 13, after insertion of a driven disc or clutch 
plate 15. The flywheel 13 is fixed for rotation with a first shaft (not 
shown), in practice the driving shaft, and the clutch plate 15 is fixed 
for rotation with a second shaft, in practice the driven shaft, likewise 
not shown. 
In the embodiments of FIGS. 1-11 the reaction plate 13 is a flat reaction 
plate, in other words, it is devoid of any cylindrical lateral wall, the 
securement of the cover assembly to the reaction plate 13 is effected 
substantially in axial alignment with the surface of the reaction plate 13 
against which the clutch plate 15 is applied. 
In conjunction therewith the cover 10 of the cover assembly which has a 
transverse front wall 11 generally perpendicular to its axis against which 
the axially acting resilient means associated with the pressure plate 11 
bear, also comprises a lateral wall 19 generally parallel to the axis for 
defining with the reaction plate 13 a space for accommodating the axially 
acting resilient means, the pressure plate 11 and the clutch plate 15. 
The lateral wall 19 of the cover 10 at the end opposite the transverse wall 
18 comprises a radially outwardly extending flange 20. The radial flange 
20 forms generally two types of areas at two different axial locations. 
The areas 21 are three in number in the illustrated embodiments of FIGS. 
1-11 and are uniformally angularly spaced from one another. They each 
comprise two holes 22 for screws and therebetween a hole 23 for a 
centering pin. 
The other areas 25 which are retracted or set back relative to areas 21 and 
the transverse wall 18 are provided for securing the pressure plate 11 to 
the cover 10 as will be described below. Each of six areas 25 comprises a 
hole 24 in the illustrated embodiment and they angularly flank areas 21. 
But in practice for a given direction of rotation of the cover assembly in 
operation as designated by arrow F1 in FIG. 1, only three of the areas 25 
are utilized. In particular, the areas 25 which for the direction of 
rotation are after or downstream of the corresponding areas 21. In case 
the cover assembly has to rotate in the opposite direction of rotation to 
that indicated by arrow F1 in FIG. 1, the other three areas 25 are used. 
Thus, a single cover 10, of symmetrical construction, advantageously may 
be used for cover assemblies adapted to rotate in either direction of 
rotation. 
From one area 21 to another, surrounding the corresponding areas 25, the 
radial flange 20 of the cover 10 borders wide cutouts 26 in the transverse 
wall 19 of the cover 10. In alignment with each area 21, the lateral wall 
19 has an opening 28 for taking part in the ventilation of the interior of 
the cover 10 and ejecting dust which may develop in the space by reason of 
the inevitable wear of the friction facings of the clutch plate 15. 
For securement to the cover 10, the pressure plate 11 has radially 
extending lugs 29, three as shown, extending into notches 26 in the cover 
10, in the middle of the notches 26 between two areas 25 of the radial 
flange 20 on the cover 10 and radially outside the lateral wall 19 of the 
cover. 
Each of the radial lugs 29 on the pressure plate 11 is attached to an area 
25 on the radial flange 20 of the cover 10 corresponding to the direction 
of rotation selected, by a series of straps 30 disposed transversely and 
chordally of the assembly and which are connected at their other ends by 
rivets 31 to a lug 29 on the pressure plate 11 and at their other ends by 
rivets 32 on the areas 25 on the radial flange 20 of the cover 10. The 
straps 30 comprise attachment means for connecting the pressure plate 11 
for rotation with the cover 10 while permitting limited axial displacement 
of the pressure plate 11 relative to the cover 10. Also, the straps 30 
which are prebent comprise spring return means for ensuring relative 
movement of the pressure plate 11 from the reaction plate 13 to disengage 
the clutch plate 15 when the clutch is declutched. 
In the illustrated embodiments the axially acting resilient means urging 
the pressure plate 11 axially away from the cover 10 comprise a diaphragm 
spring 33 comprising a Belleville washer outer peripheral portion 34 and a 
central portion divided into radial fingers 35 separated by radial slots 
36. The Belleville washer peripheral portion 34 bears against an annular 
bead 35 formed in the cover 10 and against axial bosses 37 formed at 
circumferentially spaced locations and axially protruding from the inner 
surface of the pressure plate 11, which faces toward the cover 10. 
Mounting means rockably mount the diaphragm spring 33 on the cover 10. In 
the illustrated embodiment the mounting means comprise lugs 39 integrally 
formed with the cover 10 and extending through openings 40 formed at the 
bases of the slots 36 in the diaphragm spring 33. The lugs 39 have a 
radially outwardly bent portion extending around a stamped fulcrum ring 42 
which bears against the radially bent portion 41. The fulcrum ring 42 has 
an annular bead 44 similar to and facing opposite the annular bead 35' in 
the cover 10. The beads 35' and 44 define the actual fulcrums for the 
diaphragm spring 33. 
The peripheral portion 34 of the diaphragm spring 33 urges the pressure 
plate 11 axially in the direction of arrow F2 in FIG. 3 toward a position 
protruding outside the interior of the cover 10 for clamping the clutch 
plate 15 between the pressure plate 11 and the reaction plate 13 to 
maintain the clutch in its engaged position. The ends of the radial 
fingers 35 of the diaphragm spring 33 are adapted to come into operative 
contact with a release bearing (not shown) which acts in the direction 
indicated by arrow F2 in FIG. 3 which relieves the force applied to the 
pressure plate 11 thereby unclamping clutch plate 15 and disengaging the 
clutch. 
In the illustrated embodiments there are provided at the inner periphery of 
the cover 10 between the lugs 39, radially inwardly extending abutment 
tabs 45 which are adapted to provide an axial abutment for the radial 
fingers 36 of the diaphragm spring 33 to limit the disengagement travel of 
the diaphragm spring 33 when the cover assembly is unloaded, that is, when 
the cover assembly is not mounted on the reaction plate 13. 
Abutment means are also provided for axially retaining the pressure plate 
11 after a predetermined axial travel of the pressure plate 11 relative to 
the cover 10 under the action of the diaphragm spring 33. The abutment 
means comprise at least one radial retaining lug 46 extending from the 
cover 10 and in the vicinity of the outer periphery of the cover 10, and 
also at least one transverse shoulder 47 on the pressure plate 11, adapted 
to cooperate with the retaining lug 46. 
In the illustrated embodiment of FIGS. 1-5, there are three retaining lugs 
46 provided generally in axial alignment with the areas 21 on the radial 
flange 20 of the cover 10 and generally in radial alignment with the holes 
23 in the middle of the areas 21. Preferably, the retaining lugs 46 extend 
radially inside the lateral wall 19 of the cover 10 and are formed by the 
strikes for the openings 28 in the lateral wall 19 and therefore do not 
produce any additional or particular weakening of the cover 10. 
In the embodiment of FIGS. 1-5, the transverse shoulders 47 of the pressure 
plate 11 cooperable with the retaining lugs 46 are defined by the 
outwardly turned transverse surface of the pressure plate, that is, the 
transverse surface which faces axially away from the cover. 
Preferably, in association with each of the retaining lugs 46, the pressure 
plate 11 has along its edge a slot 48 which is in continuity with the 
associated retaining lug 46. In the embodiment of FIGS. 1-5, three such 
slots 48 are provided, each in practice consisting of an axial groove 49. 
As illustrated the axial grooves 49 are radially outwardly spaced from the 
axial bosses 37 on the pressure plate 11 and run along the main body of 
the pressure plate. Alternatively, the grooves 49 may cut radially into 
the bosses 37. 
In any event, according to the invention, the slots 48 run along the outer 
peripheral edge of the pressure plate 11 and are in continuity with their 
associated transverse shoulders 47 cooperable with the retaining lugs 46. 
In practice the axial grooves 49 of the slots 38 in the pressure plate in 
the embodiment of FIGS. 1-5 run through the edge of the main body of the 
pressure plate 11, and the axial grooves have a sufficient circumferential 
dimension to permit the passage of the retaining lugs 46 on the cover 10. 
Thereupon the axial grooves 48 permit, on assembly, the axial engagement 
of the pressure plate 11 into the interior of the cover 10, the pressure 
plate 11 being introduced in an angular orientation so that the grooves 49 
face the retaining lugs 46. After such axial engagement the pressure plate 
11 is rotated about the axis of the assembly a sufficient amount, as shown 
in FIG. 1, so that the axial grooves 49 are then circumferentially spaced 
from the retaining lugs 46. 
In the unloaded condition, particularly in the course of storage or 
handling for assembling the clutch cover assembly on the reaction plate 
13, the retaining lugs 46 serve as abutment means for the pressure plate 
11 thereby ensuring its axial retention. 
Obviously the arrangements are such that the clearance J1 between the 
retaining lugs 46 on the cover 10 and the outer transverse surface of the 
pressure plate 11 forming the transverse shoulders 47 is sufficient, 
bearing in mind the normal wear of the friction facings of the clutch 
plate 15, so that the pressure plate 11 never comes to bear against the 
retaining lugs 46 in the course of operation. 
According to an advantage of the location of the abutment means 46, 47 at 
the outer periphery of the pressure plate 11, along the edge thereof, and 
as emphasized above, the axial abutment of the pressure plate 11 occurs 
along a circumference whose diameter is proximate to that of the 
circumference corresponding to the axially acting resilient means 
application, i.e., the circumference along which the diaphragm spring 33 
bears against the pressure plate 11. This arrangement is particularly 
favorable from the viewpoint of axial retention of the pressure plate 11 
and the stresses applied to the pressure plate. 
Another advantage of the arrangement is to make the use of a shim for 
fixing the diaphraqm spring 33 in its flat position when the cover 
assembly is dismounted radially. Indeed, it is easy to insert such a shim 
between any one of the retaining lugs 46 and the corresponding shoulder 
47. The advantage is common to all the embodiments of the invention. 
In the embodiment illustrated in FIGS. 6 and 7, the lateral wall 19 of the 
cover 10 does not have the openings 28 as above, and the radial retaining 
lugs 46 provided on the cover 10 are axially offset relative to the areas 
21 on the radial flange 20, and are formed by strikes provided for this 
purpose in the lateral wall 19 of the cover 10 between the areas 21 on the 
radial flange 20 and the transverse front wall 18. 
In conjunction therewith for each radial retaining lug 46 the pressure 
plate 11 comprises facing the retaining lug 46, in the edge of the main 
body of the pressure plate, a slot 48 which comprises, as above, an axial 
groove 49 and also a circumferential groove 50, the grooves 49 and 50 
intersecting each other. 
In the embodiment of FIGS. 6 and 7, the axial groove 49 extends, as above, 
along the entire width of the main part of the pressure plate 11. Also, 
the circumferential groove 50 associated therewith extends circularly 
along the entire outer periphery of the pressure plate 11 and therefore is 
common to each of the axial grooves 49 in the pressure plate. 
In this embodiment the forward flank of the circumferential groove 50, 
closest the transverse front wall 18 of the cover 10, comprises the 
transverse shoulder 47 associated with the retaining lugs 46 and in 
continuity with the slot 48. 
An axial clearance J1 is provided, as in the preceding embodiment, between 
the forward flank of the circumferential groove 50 and the retaining lugs 
46. Consequently axial clearance J2 is provided between the other flank of 
the circumferential groove 50 and the retaining lugs 46 to permit on 
clutch disengagement the disengagement travel of the pressure plate 11 
necessary for unclamping the clutch plate 15 and also to limit this 
disengagement travel. 
Also, as above, the pressure plate 11 may upon assembly, be inserted 
axially by displacing the axial grooves 49 along the retaining lugs 46 on 
the cover and when the circumferential groove 50 in the pressure plate 11 
is in registration with the radial retaining lugs 46 by rotation of the 
pressure plate 11 about the axis of the assembly whereby the retaining 
lugs 46 are brought into engagement in the circumferential groove 50. 
Alternatively, the pressure plate 11 may be tilted to permit engagement of 
at least one of the radial retaining lugs 46 in the circumferential groove 
50, and then straightened out with engagement of the retaining lug 46 with 
the cover. The radial engagement is sufficiently great so that after 
straightening the pressure plate 11 it can then also be brought in 
engagement radially by the circumferential groove 50 onto the other 
retaining lugs 47 on the cover 10. 
In any event, in the embodiment illustrated in FIGS. 6 and 7, the 
arrangement of the retaining lugs 46 offset inwardly of the cover 10 
permits place savings in the radial direction for the clutch plate 15. 
Further, the inner end or bottom 50' of the circumferential groove 50 may 
cooperate if necessary, particularly in case of rough handling of the 
unloaded cover assembly, with the terminal surface adjacent the retaining 
lugs 46 to limit the radial displacements of the pressure plate 11, 
thereby defining radial abutment means. The straps 30 are then protected 
against damage caused by excessive radial displacement of the pressure 
plate. 
In the modified embodiment illustrated in FIG. 8 each axial groove 49 
extends only part way through the pressure plate body, up to the 
circumferential groove 50 associated therewith. As in the previous 
embodiment the circumferential groove 50 may extend over the entire 
periphery of the pressure plate 11. Alternatively, as shown, the each 
axial groove 48 is associated with its own circumferential groove 50 which 
extends only over a limited circumferential segment of the periphery of 
the pressure plate 11. 
In the latter case the terminal wall 48' of the circumferential groove 50 
may cooperate with the corresponding retaining lug 46 to define a 
circumferential abutment adapted to limit the buckling of the straps 30 in 
case clutch is rotated in the direction opposite the normal direction of 
rotation. 
In any event, as above, each axial groove 49 intersects its corresponding 
circumferential groove 50. 
In the modified embodiments of FIGS. 9-11, each of the slots 48 in the 
pressure plate 11 is formed in a radially projecting boss 52 on the edge 
of body portion of the pressure plate 11 and not in the edge of the main 
body of the pressure plate as above. Corresponding bosses (not shown) are 
of course provided in the lateral wall of the cover 10 and have a 
rigidifying function as well. 
In the embodiment of FIGS. 9 and 10, the slot 48 consists essentially of a 
circumferential groove 50. In the embodiment of FIG. 11 the slot 48 
consists essentially of an axial groove 49. 
The assembly and function of these embodiments are similar to those 
described in detail above. 
In the embodiment of FIGS. 12 and 13, the reaction plate or flywheel is a 
pot type reaction plate, i.e., it comprises a forwardly extending 
cylindrical side wall (not shown) on which the cover is mounted. 
Accordingly, the mounting plane of the cover on the reaction plate is 
spaced axially forwardly of the reaction plate/clutch plate contact 
surface. In this embodiment the assembly means for rockably mounting the 
diaphragm spring 33 on the cover 10 comprises a plurality of rivets or 
posts 60 extending from the cover through the enlarged openings 40 of the 
slots in the diaphragm spring 33, a profiled fulcrum ring 61 on the remote 
side of the diaphragm spring 33 from the cover 10, and a toroidal fulcrum 
ring on the near side of the diaphragm spring 33 relative to the cover 10. 
In this embodiment the slots 48 each comprise a circumferential groove 50 
formed in the bosses 37 against which the peripheral portion 34 of the 
diaphragm spring 33 is applied. In practice the circumferential groove 50 
extends over the entire periphery of the pressure plate. Alternatively 
there may be a plurality of circumferential grooves each for a 
corresponding retaining lug 46. In this case an end of each of the 
circumferential grooves 50 comprises a circumferential abutment with the 
corresponding retaining lug 46 for limiting the buckling of the straps 
when the clutch rotates in the direction opposite the normal direction of 
rotation. 
In addition the retaining lugs 46 are formed by the continuation of the 
radial flange on the cover 10. The inner ends of the retaining lugs 46 are 
tangent to a circumference having a diameter substantially equal to that 
of the outer periphery of the diaphragm spring. When the diameter is 
greater the positioning of the diaphragm spring in the course of assembly 
is effected by translation. When the diameter is smaller the positioning 
of the diaphragm spring is effected by tilting and then straightening the 
diaphragm spring. In either case, as above, the ends of the retaining lugs 
46 cooperable with the shoulders 47 are generally situated on the same 
circumference as the contact zone 63 of the axial bosses 37 corresponding 
to the bearing diameter of the diaphragm spring 33 on the pressure plate 
11. 
In this embodiment as above the inner end or bottom 50' of the 
circumferential groove 50 is adapted to cooperate with the terminal parts 
of the retaining lugs 46 to limit the radial movement of the pressure 
plate 11 when handling the unloaded cover assembly without any particular 
precaution. 
Further, in this embodiment advantage is taken of spaces 65 between 
circumferential ends of the bosses 37 on the pressure plate 11 which 
define transverse grooves for mounting the pressure plate 11. The pressure 
plate may be mounted by axial engagement of the retaining lugs 46 into the 
spaces 65, then the circumferential grooves 50 come into registration with 
the retaining lugs 46 to permit rotation of the pressure plate 11. 
Alternatively, assembly can be accomplished by tilting the pressure plate 
11 and then straightening it while radially engaging the retaining lugs 46 
into the circumferential grooves 50. 
The present invention is moreover not limited to the various illustrated 
and described embodiments but encompasses all modifications and 
alternatives which will be understood to those skilled in the art without 
departing from the scope of the present invention. 
Thus, although only push type clutches have been considered in the 
foregoing description the application is equally applicable to other types 
of clutches, namely pull type clutches. 
Moreover, the axially acting resilient means instead of defined by a 
diaphragm spring may comprise coil springs and/or the attachment means 
defined by chordal straps may be replaced by radial straps, etc. 
In any event, the transverse shoulder(s) on the pressure plate cooperable 
with the retaining lug(s) may, as described above, be located on the outer 
or rear surface of the main body of the pressure plate, which faces the 
reaction plate, between the inner and outer surfaces of the main body of 
the pressure plate or between the inner surface of the main body of the 
pressure plate and the contact zone with the associated axially acting 
resilient means.