United States Patent
`Macdonald
`
`[19]
`
`IIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIII
`US006053292A
`[11] Patent Number:
`[45] Date of Patent:
`
`6, 053, 292
`Apr. 25, 2000
`
`[54] TORQUE CONVERTER HAVING
`RESILIENTLY LOADED BYPASS CLUTCH
`PISTON
`
`[75]
`
`Inventor:
`
`Fraser John Macdonald, Farmington
`Hills, Mich.
`
`[73] Assignee: Ford Global Technologies, Inc. ,
`Dearborn, Mich.
`
`. . . . . . . . . .
`5, 477, 950 12/1995 Maloof
`5, 826, 688 10/1998 Arhab et al. . .
`Primary Examiner — Charles A Marmor
`Assistant Examiner — Tisha D. Waddell
`Attorney, Agent, or Firm~rank G. McKenzie
`
`[57]
`
`ABSTRACT
`
`192/3. 29
`192/3. 29
`
`[21] Appl. No. : 09/237, 983
`Jan. 25, 1999
`
`[22] Filed:
`[51] Int. Cl.
`[52] U. S. Cl.
`[58] Field of Search
`
`. . . . . . . . . . . . . . . . .
`
`F16D 33/00
`. 192/3. 28; 192/3. 3
`. . . . . . . . 192/3. 29, 3. 3,
`192/3. 31
`
`[56]
`
`References Cited
`U. S. PATENT DOCUMENTS
`
`A hydrokinetic
`includes an impeller cover
`torque converter
`and a bypass clutch. A drive ring is located between adjacent
`surfaces of the cover and a clutch piston, which moves
`is welded
`surface. The piston
`axially on a support
`at a
`is sup-
`to thin clutch plate, which
`radially outer position
`ported at another radial location on the cover. As the piston
`moves into engagement with the ring and cover, the clutch
`this movement by bending elastically. When
`plate permits
`is reduced, energy stored in the clutch
`clutch apply pressure
`plate is used to move the piston out of engagement with the
`drive ring and cover.
`
`5, 383, 540
`
`1/1995 MacDonald
`
`192/3. 29
`
`8 Claims, 3 Drawing Sheets
`
`ao
`
`)
`
`SO
`
`Valeo Exhibit 1026, pg. 1
`
`

`
`U. S. Patent
`
`Apr. 25, 2000
`
`Sheet 1 of 3
`
`6, 053, 292
`
`AC
`
`Valeo Exhibit 1026, pg. 2
`
`

`
`U. S. Patent
`
`Apr. 25, 2000
`
`Sheet 2 of 3
`
`6, 053, 292
`
`70
`
`Valeo Exhibit 1026, pg. 3
`
`

`
`U. S. Patent
`
`Apr. 25, 2000
`
`Sheet 3 of 3
`
`6, 053, 292
`
`74'
`
`Valeo Exhibit 1026, pg. 4
`
`

`
`6, 053, 292
`
`TORQUE CONVERTER HAVING
`RESILIENTLY LOADED BYPASS CLUTCH
`PISTON
`
`BACKGROUND OF THE INVENTION
`1. Field of the Invention
`relates to the field of automatic
`transmis-
`This invention
`torque converters. The invention pertains
`sion hydrokinetic
`to a bypass clutch for a torque converter.
`particularly
`2. Description of the Prior Art
`A device for deducing noise and vibration
`in a torque
`in U. S. Pat. No. 5, 477,
`converter bypass clutch is described
`to the assignee of this invention. The
`950, which is assigned
`torque converter
`includes an impeller wheel
`hydrokinetic
`and turbine wheel. The housing for the impeller
`includes a
`lockup clutch assembly having a clutch plate that engages a
`friction surface on the impeller housing. The clutch plate
`carries friction material
`that establishes a frictional driving
`connection between
`turbine when
`the
`and
`impeller
`the
`dilferential pressure across the clutch plate is sufflcient
`to
`force.
`establish a clutch-engaging
`The clutch plate is connected
`through a damper assembly
`to the hub of the turbine,
`a mechanical
`thus establishing
`torque transfer between an engine crankshaft and the turbine
`shaft, which bypasses
`the hydrokinetic
`flow path
`torque
`the torque converter.
`through
`The clutch plate is both welded to the impeller cover and
`the pin that con-
`to the clutch piston. Furthermore,
`pinned
`nects the piston and plate carries a spring-loaded detent ball
`that is forced radially outward
`from the piston into contact
`with the plate. This arrangement driveably connects the plate
`the components of
`torque between
`and piston, and transmits
`the assembly without producing noise, despite engine speed
`torque and speed variations.
`that a minimum number of parts be used
`It is preferable
`the impeller cover
`to produce a resilient connection between
`and bypass clutch piston including elimination of the thrust
`the turbine hub and clutch piston.
`washer between
`
`SUMMARY OF THE INVENTION
`It is an object of the present
`to prevent
`invention
`torque
`converter bypass clutch
`idle rattle, a noise generated by
`engine firing pulses at idle speed, by eliminating backlash
`the converter cover and bypass clutch piston. It is
`between
`another object to eliminate
`impact loads associated with this
`increasing durability of the bypass clutch.
`backlash,
`thereby
`these objects with the advan-
`This invention accomplishes
`tage that the number of parts is minimized and the construc-
`tion is simplified
`in relation to a conventional bypass clutch
`arrangement.
`these objects and advantages, a bypass clutch,
`In realizing
`according to this invention,
`includes a bladed wheel, such as
`a turbine wheel, supported for rotation about an axis; a cover
`for rotation about
`the axis and having
`a first
`supported
`for displace-
`surface facing the wheel; a piston supported
`to the cover and for rotation about said axis,
`ment relative
`the first surface; a clutch
`having a second surface facing
`located between
`the piston and casing, fixed to the
`plate
`fixed to the cover at a second
`piston at a first location,
`the disc
`the first location,
`location spaced
`from
`radially
`for elastic bending deflection between
`the first
`adapted
`location and second location due to movement of the piston
`to resist move-
`to the cover, said deflection
`relative
`tending
`ment of the piston toward
`the cover and tending
`to displace
`the piston away from the cover; and a drive ring supported
`
`for axial displacement, having a radial leg located between
`the first surface and the second surface, the piston adapted
`to driveably engage the drive ring and the drive ring adapted
`the clutch plate as the clutch is applied
`to driveably engage
`5 and the clutch plate deflects.
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`FIG. 1 is a cross section of a torque converter,
`taken at a
`plane defined by axial and lateral axes, showing a bypass
`clutch according
`to the invention.
`FIGS. 2 — 4 are cross sections of the torque converter of
`FIG. 1 in the vicinity of the bypass clutch piston showing
`the
`piston at various positions along its range of travel.
`FIG. 5 is a cross section showing an alternate embodiment
`of the invention.
`
`DESCRIPTION OF THE PREFERRED
`EMBODIMENT
`
`first to FIG. 1, a torque converter
`Referring
`includes an
`impeller cover 12 welded
`shell 14 having
`to an impeller
`tabs 18 located on the outer
`recesses 16, which
`receive
`surface of impeller blades 20. The
`impeller blades are
`retained between shell 14 and an inner impeller shroud 22.
`Cover 12 is driveably connected
`to an engine crankshaft.
`Impeller cover 12 supports a circular pattern of threaded
`studs 24 to which a flywheel,
`supported on the
`rotatably
`is bolted,
`thereby driveably connecting
`engine crankshaft,
`the cover to an engine.
`about the axis of
`Turbine blades 26 are spaced mutually
`rotation and are located with respect to the impeller blades
`so that a toroidal fluid flow path within
`the torque converter
`exits the impeller and enters the turbine at the radially outer
`inner area. The
`area and leaves
`the turbine at the radially
`outer periphery of the turbine blades is fixed mechanically or
`shell 28, which has
`by welding or brazing
`to a turbine
`tabs 30 formed on the
`openings 29 that receive
`turbine
`blades. The inner periphery of the turbine blades
`is con-
`tabs 34
`shroud 32 by locating
`to an inner
`nected
`turbine
`in shroud 32 and by bending
`within slots formed
`the tabs
`inner surface of the shroud,
`over
`fixing
`the
`the
`thereby
`shell 28 and shroud 32.
`position of blades 26 between
`Turbine shell 28 and retainer 97 are secured by rivets 36 to
`a turbine hub 38 having an internally
`splined surface 40
`splined surface on a trans-
`to engage an externally
`adapted
`input shaft 42.
`mission
`the flow exit section of the turbine and
`Located between
`the flow entrance section of the impeller is a stator assembly
`stator blades 46, spaced mutually
`the
`comprising
`around
`axis of rotation, a hub 48 supporting blades 46, an inner
`tips of the stator
`shroud 50 connecting
`inner
`the radially
`blades, and an outer shroud 52 connecting
`the radially outer
`ends of the stator blades. An overrunning brake 54, fixed by
`splines 56 to a stationary shaft 57, provides one-way braking
`the stator blades 46 and the sleeve shaft.
`between
`A bypass clutch includes a piston 60 formed with a flange
`61 that is slideably mounted on an axially directed surface
`62 formed on turbine hub 38 and sealed against the passage
`of hydraulic
`fluid by an 0-ring seal 64, located in a recess
`in surface 62.
`formed
`A clutch plate 70 is fixed to the inner surface of impeller
`cover 12 by a 360 degree laser weld or resistance weld 72
`located near a radially outer edge of the plate. The weld
`the passage of hydraulic
`a seal against
`provides
`fluid
`between the axially outer surface of plate 70 and the adjacent
`inner surface of the cover 12. Plate 70 is welded similarly
`to
`
`10
`
`15
`
`20
`
`25
`
`30
`
`35
`
`40
`
`45
`
`50
`
`55
`
`60
`
`65
`
`Valeo Exhibit 1026, pg. 5
`
`

`
`6, 053, 292
`
`piston 60 by a 360 degree laser weld or resistance weld 73
`inner edge of the plate. Clutch plate
`located near a radially
`70 and piston 60 are driveably connected when
`the bypass
`frictional engagement.
`clutch is engaged due to mutual
`Drive ring 74 includes a radial leg, located between
`the
`axial inner face 76 of clutch plate 70 and the outer face of
`piston 60; and axial legs 78, spaced mutually
`angularly
`the axis of rotation and directed
`toward
`about
`the turbine
`wheel. The surfaces of the radial leg that face plate 70 and
`piston 60 carry friction material 80, commonly referred to as
`"paper face" material, bonded
`to the axially
`radial
`inner
`surface of plate 70 by a bonding
`technique described by
`Frosbie, Milek and Smith in SAE Design Practices, Vol. 5
`(1962).
`Drive ring 74 is supported
`for axial sliding movement as
`it moves toward plate 70 due to contact with piston 60 and
`away from the plate as pressure within control chamber 82
`varies in relation to pressure on the axially opposite side of
`the piston.
`Each of the legs 78 of drive ring 74 is located for contact
`spring, as described below. The
`with a damper
`turbine
`shroud 28 and a torque converter damper spring retainer 84
`flange of turbine hub 38 at
`are joined to a radially extending
`a riveted connection 36. At the radially outer end of retainer
`84, several arcuate spring retainer flanges 86, spaced angu-
`to the location
`larly about the axis at intervals corresponding
`lengths of the damper springs 88, are formed.
`and arcuate
`Flanges 86 define a substantially
`circular
`tubular cavity, in
`which are located four angularly
`spaced, helically-coiled
`damper springs 88. Preferably,
`two longer damper springs
`are formed with an actuate shape;
`two shorter springs are
`formed straight and then bent to the contour of the arcuate
`flanges 86, in which
`they are located. At four angularly
`the central axis of the
`locations
`spaced
`about
`torque
`flange 86 of the damper
`support 84 is formed
`converter,
`integrally with local stop flanges 90, adjacent pairs of stop
`flanges, which define the extremities of annular pockets of
`the damper where each spring 88 is located. Each stop flange
`provides a surface that stops an end of a spring from moving
`to displacement of the legs 78. Details of the
`in response
`in U. S. Ser. No. OS/891, 911,
`damper assembly are described
`filed Jul. 14, 1997, which application
`to the
`is assigned
`assignor of this invention.
`toward clutch plate 70 due to
`Piston 60 moves axially
`dilferential hydraulic pressure across the piston and away
`from the clutch plate as pressure within control chamber 82
`rises in relation to pressure on the axially opposite side of the
`piston. Piston 60 also rotates about
`it is
`the axis when
`driveably connected to plate 70 because impeller cover 12 is
`connected to the engine crankshaft. This rotary movement of
`the piston forces legs 78 into contact with the ends of springs
`88 causing
`to compress, store energy and dissipate
`them
`energy due to contact of the spring on the inner surfaces of
`flanges 86.
`Each of the axially directed legs 78 of the drive ring 74 is
`located within a space located between angularly opposite
`ends of each of the damper
`is
`springs. Engine
`torque
`through piston 60 to the damper assembly by
`transmitted
`bearing contact between axial legs 78 and the adjacent ends
`of the damper springs.
`Chamber 82, bounded by piston 60, cover 12, and clutch
`plate 70, is a control pressure chamber, which communicates
`with a control pressure source through a passage in a manner
`in U. S. Pat. No. 4, 633, 738, which is assigned
`described
`to
`the assignor of this invention. By controlling pressure
`in
`chamber 82, a pressure dilferential across piston 60 can be
`
`5
`
`10
`
`15
`
`20
`
`25
`
`30
`
`35
`
`40
`
`45
`
`50
`
`55
`
`60
`
`65
`
`controlled. The pressure
`torus flow cavity on the
`in the
`left-hand side of piston 60 tends to move the piston and ring
`74 rightward. This movement
`causes
`facing
`the mutually
`surfaces on clutch plate 70, ring 74 and piston 60 to become
`to frictional contact. By appropri-
`driveably engaged due
`in chamber 82, controlled
`ately modulating
`the pressure
`the cover and piston. Torque
`slipping will occur between
`in the driveline due to engine
`fluctuation developed
`torque
`and other torque transmitting
`irregularities
`perturbations
`are
`through operation of the damper assembly.
`modulated
`is driveably connected
`The piston
`the damper
`through
`to retainer
`resiliently
`assembly
`the damper springs
`through
`at rivets 36 to the turbine rotor, and
`84, via the attachment
`through hub 38 to the transmission
`input shaft 42.
`FIG. 2 shows piston 60 located at the left-hand extremity
`of its travel and out of contact with drive ring 74 and clutch
`plate 70, the bypass clutch being disengaged. The piston is
`urged to this location due to elastic, resilient flexure of plate
`70 when
`across
`is
`dilferential
`the piston
`the pressure
`removed. When dilferential pressure across the clutch piston
`60 rises, the piston moves rightward on surface 62 to the
`position of FIG. 3 against the resistance caused by bending
`the thickness of plate 70. As dilferential pressure
`through
`across the clutch piston 60 rises further,
`the piston moves
`rightward on surface 62 to the position of FIG. 4
`further
`the resistance caused by bending of plate 70. This
`against
`into frictional contact with
`the friction
`the piston
`brings
`material on disc 74 and forces the disc into frictional contact
`with plate 70, thereby
`the torque converter
`fully engaging
`bypass clutch.
`is reduced,
`When clutch apply pressure
`the potential
`energy stored in disc 70 due to its flexural deformation
`is
`used to move the disc leftward on surface 62 to the position
`of FIG. 2.
`resilient elements, such as Belleville,
`Various elastically
`wave, strap, finger, coil, or clock springs may be substituted
`for the disc springs or plate 70 described above.
`Riveting or bolting may be used instead of welding
`to
`attach the disc to the cover or piston. For example, FIG. 5
`in which a disc 71
`shows an alternate form of the invention
`to the piston 61 by angularly spaced rivets 96.
`is connected
`Disc 71, symmetrically disposed about the central axis of the
`assembly, closely conforms to that portion of the contour of
`inward of rivets 96. In this
`cover 12 that is located radially
`way disc 71 is fixed to the piston at the location of the rivets
`96 and is supported
`in bending on the cover at the location,
`at the base of the conical surface of the disc where the cover
`and disc are in mutual contact.
`Flexural deformation of disc 71 permits movement of the
`frictional engagement of
`causing mutual
`piston rightward
`the piston, drive ring 74 and cover 12. When clutch apply
`in disc 71
`is reduced,
`the potential energy stored
`pressure
`the disc
`is used
`to its flexural deformation
`to move
`due
`leftward on surface 62 to the disengaged position.
`Discs 70 and 71 are 1. 0 — 1. 5 mm
`thick and preferably
`low carbon alloy 950 structural
`formed of high strength,
`sheet steel.
`Since there is no running clearance to permit axial move-
`ment of the piston, no impact noise
`is possible despite
`engine firing pulses.
`the form of the invention shown and described
`Although
`the preferred embodiment of the invention,
`here constitutes
`forms of the
`it is not
`all possible
`to illustrate
`intended
`invention. Words used here are words of description
`rather
`than of limitation. Various changes
`form of the
`the
`in
`invention may be made without departing from the spirit and
`scope of the invention as disclosed.
`
`Valeo Exhibit 1026, pg. 6
`
`

`
`6, 053, 292
`
`for
`
`I claim:
`1. Abypass clutch for the torque converter of an automatic
`for an automotive vehicle, comprising:
`transmission
`a cover fixed against axial displacement,
`supported
`rotation about an axis, having a first surface;
`for rotation about said axis, having a
`a piston supported
`second surface facing the first surface, the piston sup-
`ported for displacement
`to said cover; and
`relative
`a clutch plate located between the piston and casing, fixed
`location,
`to
`at a first
`the piston
`against
`supported
`the cover at a second
`location
`displacement
`toward
`spaced radially from the first location, the clutch plate
`adapted for elastic bending deflection between
`the first
`location and second location due to movement of the
`to
`to the cover, said deflection
`piston relative
`tending
`resist movement of the piston
`the cover and
`toward
`the piston away from the cover.
`to displace
`tending
`2. The bypass clutch of claim 1, further comprising:
`fixing the piston and clutch plate at &o
`a first weld mutually
`the first location; and
`fixing the clutch plate and cover
`a second weld mutually
`at the second location.
`3. The bypass clutch of claim 1, further comprising:
`the piston and clutch plate at 33
`first rivets fixing mutually
`the first location; and wherein
`the clutch plate is supported on the cover at the second
`location due to mutual contact at the second location of
`the clutch plate and cover.
`4. The bypass clutch of claim 1, further comprising a drive 30
`for axial displacement,
`having a radial
`ring supported
`leg
`the first surface and the second surface, the
`located between
`to driveably engage
`piston adapted
`the drive ring and the
`drive ring adapted to driveably engage the clutch plate as the
`clutch is applied and the clutch plate deflects.
`5. Abypass clutch for the torque converter of an automatic
`for an automotive vehicle, comprising:
`transmission
`for rotation about an axis;
`a bladed wheel supported
`a cover supported
`for rotation about said axis, fixed
`against axial displacement, having a first surface facing
`the wheel;
`to said cover
`for displacement
`relative
`a piston supported
`a second
`for rotation
`about said axis, having
`and
`surface facing the first surface;
`a clutch plate located between the piston and casing, fixed
`location,
`to
`at a first
`the piston
`against
`supported
`the cover at a second
`location
`displacement
`toward
`spaced radially from the first location, the clutch plate
`
`35
`
`4O
`
`45
`
`adapted for elastic bending deflection between
`the first
`location and second location due to movement of the
`to the cover, said deflection
`piston relative
`to
`tending
`resist movement of the piston
`the cover and
`toward
`to displace the piston away from the cover; and
`tending
`for axial displacement,
`a drive ring supported
`having a
`leg located between
`the first surface and
`radial
`the
`second surface, the piston adapted
`to driveably engage
`the drive ring and the drive ring adapted
`to driveably
`engage the clutch plate as the clutch is applied and the
`clutch plate deflects.
`6. The bypass clutch of claim 5, further comprising:
`the piston and clutch plate at
`first rivets fixing mutually
`the first location; and wherein
`the clutch plate is supported on the cover at the second
`location due to mutual contact at the second location of
`the clutch plate and cover.
`7. Abypass clutch for the torque converter of an automatic
`for an automotive vehicle, comprising:
`transmission
`for rotation about an axis;
`a bladed wheel supported
`a cover supported
`for rotation about said axis, fixed
`against axial displacement, having a first surface facing
`the wheel;
`to said cover
`for displacement
`relative
`a piston supported
`for rotation
`a second
`about said axis, having
`and
`surface facing the first surface;
`a clutch plate located between the piston and casing, fixed
`to the piston at a first location, fixed to the cover at a
`second location spaced radially from the first location,
`the clutch plate adapted for elastic bending deflection
`the first location and second location due to
`between
`movement of the piston
`to the cover, said
`relative
`to resist movement of the piston
`deflection
`tending
`the cover and tending
`to displace
`toward
`the piston
`away from the cover; and
`for axial displacement,
`a drive ring supported
`having a
`leg located between
`the first surface and
`radial
`the
`second surface, the piston adapted
`to driveably engage
`the drive ring and the drive ring adapted
`to driveably
`engage the clutch plate as the clutch is applied and the
`clutch plate deflects.
`8. The bypass clutch of claim 7 further comprising:
`fixing the piston and clutch plate at
`a first weld mutually
`the first location; and
`fixing the clutch plate and cover
`a second weld mutually
`at the second location.
`
`Valeo Exhibit 1026, pg. 7