Patent Description:
A torque converter is a fluid coupling device that is used to transfer rotating power from a power unit, such as an engine or electric motor, to a power-transferring device such as a transmission. A torque converter can have a clutch system to allow the torque converter to be selectable for either fluid coupling or mechanical coupling depending on the engagement of the clutch system. The transmission is an apparatus through which power and torque can be transmitted from a vehicle's power unit to a load-bearing device such as a drive axis. Conventional transmissions include a variety of gears, shafts, and clutches that transmit torque therethrough. A torque converter with a lockup clutch according to the preamble of claim <NUM> is known from <CIT>.

According to the invention, a torque converter with a lockup clutch as defined in claim <NUM> is provided. The dependent claims define preferred and/or advantageous embodiments of the invention.

The above-mentioned aspects of the present invention and the manner of obtaining them will become more apparent and the invention itself will be better understood by reference to the following description of the embodiments of the invention, taken in conjunction with the accompanying drawings, wherein:.

The embodiments of the present invention described below are not intended to be exhaustive or to limit the invention to the precise forms disclosed in the following detailed description. Rather, the embodiments are chosen and described so that others skilled in the art may appreciate and understand the principles and practices of the present invention, which is defined by the appended claims.

The terminology used herein is for the purpose of describing particular illustrative embodiments only and is not intended to be limiting. Similarly, plural forms may have been used to describe particular illustrative embodiments when singular forms would be applicable as well.

Referring now to <FIG>, a block diagram and schematic view of one illustrative embodiment of a vehicular system <NUM> having a drive unit <NUM> and transmission <NUM> is shown. In the illustrated embodiment, the drive unit <NUM> may include an internal combustion engine, diesel engine, electric motor, or other power-generating device. The drive unit <NUM> is configured to rotatably drive an output shaft <NUM> that is coupled to an input or pump shaft <NUM> of a conventional torque converter <NUM>. The input or pump shaft <NUM> is coupled to an impeller or pump <NUM> that is rotatably driven by the output shaft <NUM> of the drive unit <NUM>. The torque converter <NUM> further includes a turbine <NUM> that is coupled to a turbine shaft <NUM>, and the turbine shaft <NUM> is coupled to, or integral with, a rotatable input shaft <NUM> of the transmission <NUM>. The transmission <NUM> can also include an internal pump <NUM> for building pressure within different flow circuits (e.g., main circuit, lube circuit, etc.) of the transmission <NUM>. The pump <NUM> can be driven by a shaft <NUM> that is coupled to the output shaft <NUM> of the drive unit <NUM>. In this arrangement, the drive unit <NUM> can deliver torque to the shaft <NUM> for driving the pump <NUM> and building pressure within the different circuits of the transmission <NUM>.

The transmission <NUM> can include a planetary gear system <NUM> having a number of automatically selected gears. An output shaft <NUM> of the transmission <NUM> is coupled to or integral with, and rotatably drives, a propeller shaft <NUM> that is coupled to a conventional universal joint <NUM>. The universal joint <NUM> is coupled to, and rotatably drives, an axle <NUM> having wheels 134A and 134B mounted thereto at each end. The output shaft <NUM> of the transmission <NUM> drives the wheels 134A and 134B in a conventional manner via the propeller shaft <NUM>, universal joint <NUM> and axle <NUM>.

A conventional lockup clutch <NUM> is connected between the pump <NUM> and the turbine <NUM> of the torque converter <NUM>. The operation of the torque converter <NUM> is conventional in that the torque converter <NUM> is operable in a so-called "torque converter" mode during certain operating conditions such as vehicle launch, low speed and certain gear shifting conditions. In the torque converter mode, the lockup clutch <NUM> is disengaged and the pump <NUM> rotates at the rotational speed of the drive unit output shaft <NUM> while the turbine <NUM> is rotatably actuated by the pump <NUM> through a fluid (not shown) interposed between the pump <NUM> and the turbine <NUM>. In this operational mode, torque multiplication occurs through the fluid coupling such that the turbine shaft <NUM> is exposed to drive more torque than is being supplied by the drive unit <NUM>, as is known in the art. The torque converter <NUM> is alternatively operable in a so-called "lockup" mode during other operating conditions, such as when certain gears of the planetary gear system <NUM> of the transmission <NUM> are engaged. In the lockup mode, the lockup clutch <NUM> is engaged and the pump <NUM> is thereby secured directly to the turbine <NUM> so that the drive unit output shaft <NUM> is directly coupled to the input shaft <NUM> of the transmission <NUM>, as is also known in the art.

The transmission <NUM> further includes an electro-hydraulic system <NUM> that is fluidly coupled to the planetary gear system <NUM> via a number, J, of fluid paths, <NUM><NUM>-<NUM>J, where J may be any positive integer. The electro-hydraulic system <NUM> is responsive to control signals to selectively cause fluid to flow through one or more of the fluid paths, <NUM><NUM>-<NUM>J, to thereby control operation, i.e., engagement and disengagement, of a plurality of corresponding friction devices in the planetary gear system <NUM>. The plurality of friction devices may include, but are not limited to, one or more conventional brake devices, one or more torque transmitting devices, and the like. Generally, the operation, i.e., engagement and disengagement, of the plurality of friction devices is controlled by selectively controlling the friction applied by each of the plurality of friction devices, such as by controlling fluid pressure to each of the friction devices. In one example embodiment, which is not intended to be limiting in any way, the plurality of friction devices include a plurality of brake and torque transmitting devices in the form of conventional clutches that may each be controllably engaged and disengaged via fluid pressure supplied by the electro-hydraulic system <NUM>. In any case, changing or shifting between the various gears of the transmission <NUM> is accomplished in a conventional manner by selectively controlling the plurality of friction devices via control of fluid pressure within the number of fluid paths <NUM><NUM>-<NUM>J.

The system <NUM> further includes a transmission control circuit <NUM> that can include a memory unit <NUM>. The transmission control circuit <NUM> is illustratively microprocessor-based, and the memory unit <NUM> generally includes instructions stored therein that are executable by a processor of the transmission control circuit <NUM> to control operation of the torque converter <NUM> and operation of the transmission <NUM>, i.e., shifting between the various gears of the planetary gear system <NUM>. It will be understood, however, that this invention contemplates other embodiments in which the transmission control circuit <NUM> is not microprocessor-based, but is configured to control operation of the torque converter <NUM> and/or transmission <NUM> based on one or more sets of hardwired instructions and/or software instructions stored in the memory unit <NUM>.

In the system <NUM> illustrated in <FIG>, the torque converter <NUM> and the transmission <NUM> include a number of sensors configured to produce sensor signals that are indicative of one or more operating states of the torque converter <NUM> and transmission <NUM>, respectively. For example, the torque converter <NUM> illustratively includes a conventional speed sensor <NUM> that is positioned and configured to produce a speed signal corresponding to the rotational speed of the pump shaft <NUM>, which is the same rotational speed of the output shaft <NUM> of the drive unit <NUM>. The speed sensor <NUM> is electrically connected to a pump speed input, PS, of the transmission control circuit <NUM> via a signal path <NUM>, and the transmission control circuit <NUM> is operable to process the speed signal produced by the speed sensor <NUM> in a conventional manner to determine the rotational speed of the turbine shaft <NUM>/drive unit output shaft <NUM>.

The transmission <NUM> illustratively includes another conventional speed sensor <NUM> that is positioned and configured to produce a speed signal corresponding to the rotational speed of the transmission input shaft <NUM>, which is the same rotational speed as the turbine shaft <NUM>. The input shaft <NUM> of the transmission <NUM> is directly coupled to, or integral with, the turbine shaft <NUM>, and the speed sensor <NUM> may alternatively be positioned and configured to produce a speed signal corresponding to the rotational speed of the turbine shaft <NUM>. In any case, the speed sensor <NUM> is electrically connected to a transmission input shaft speed input, TIS, of the transmission control circuit <NUM> via a signal path <NUM>, and the transmission control circuit <NUM> is operable to process the speed signal produced by the speed sensor <NUM> in a conventional manner to determine the rotational speed of the turbine shaft <NUM>/transmission input shaft <NUM>.

The transmission <NUM> further includes yet another speed sensor <NUM> that is positioned and configured to produce a speed signal corresponding to the rotational speed of the output shaft <NUM> of the transmission <NUM>. The speed sensor <NUM> may be conventional, and is electrically connected to a transmission output shaft speed input, TOS, of the transmission control circuit <NUM> via a signal path <NUM>. The transmission control circuit <NUM> is configured to process the speed signal produced by the speed sensor <NUM> in a conventional manner to determine the rotational speed of the transmission output shaft <NUM>.

In the illustrated embodiment, the transmission <NUM> further includes one or more actuators configured to control various operations within the transmission <NUM>. For example, the electro-hydraulic system <NUM> described herein illustratively includes a number of actuators, e.g., conventional solenoids or other conventional actuators, that are electrically connected to a number, J, of control outputs, CP<NUM> - CPJ, of the transmission control circuit <NUM> via a corresponding number of signal paths <NUM><NUM> - <NUM>J, where J may be any positive integer as described above. The actuators within the electro-hydraulic system <NUM> are each responsive to a corresponding one of the control signals, CP<NUM> - CPJ, produced by the transmission control circuit <NUM> on one of the corresponding signal paths <NUM><NUM> - <NUM>J to control the friction applied by each of the plurality of friction devices by controlling the pressure of fluid within one or more corresponding fluid passageway <NUM><NUM> - <NUM>J, and thus control the operation, i.e., engaging and disengaging, of one or more corresponding friction devices, based on information provided by the various speed sensors <NUM>, <NUM>, and/or <NUM>.

The friction devices of the planetary gear system <NUM> are illustratively controlled by hydraulic fluid which is distributed by the electro-hydraulic system in a conventional manner. For example, the electro-hydraulic system <NUM> illustratively includes a conventional hydraulic positive displacement pump (not shown) which distributes fluid to the one or more friction devices via control of the one or more actuators within the electro-hydraulic system <NUM>. In this embodiment, the control signals, CP<NUM> - CPJ, are illustratively analog friction device pressure commands to which the one or more actuators are responsive to control the hydraulic pressure to the one or more frictions devices. It will be understood, however, that the friction applied by each of the plurality of friction devices may alternatively be controlled in accordance with other conventional friction device control structures and techniques, and such other conventional friction device control structures and techniques are contemplated by this invention. In any case, however, the analog operation of each of the friction devices is controlled by the control circuit <NUM> in accordance with instructions stored in the memory unit <NUM>.

In the illustrated embodiment, the system <NUM> further includes a drive unit control circuit <NUM> having an input/output port (I/O) that is electrically coupled to the drive unit <NUM> via a number, K, of signal paths <NUM>, wherein K may be any positive integer. The drive unit control circuit <NUM> may be conventional, and is operable to control and manage the overall operation of the drive unit <NUM>. The drive unit control circuit <NUM> further includes a communication port, COM, which is electrically connected to a similar communication port, COM, of the transmission control circuit <NUM> via a number, L, of signal paths <NUM>, wherein L may be any positive integer. The one or more signal paths <NUM> are typically referred to collectively as a data link. Generally, the drive unit control circuit <NUM> and the transmission control circuit <NUM> are operable to share information via the one or more signal paths <NUM> in a conventional manner. In one embodiment, for example, the drive unit control circuit <NUM> and transmission control circuit <NUM> are operable to share information via the one or more signal paths <NUM> in the form of one or more messages in accordance with a society of automotive engineers (SAE) J-<NUM> communications protocol, although this invention contemplates other embodiments in which the drive unit control circuit <NUM> and the transmission control circuit <NUM> are operable to share information via the one or more signal paths <NUM> in accordance with one or more other conventional communication protocols (e.g., from a conventional databus such as J1587 data bus, J1939 data bus, IESCAN data bus, GMLAN, Mercedes PT-CAN).

Referring to <FIG>, one embodiment is shown of a top half, cross-sectional view of a conventional torque converter <NUM>. Torque converter <NUM> includes a front cover assembly <NUM> fixedly attached to a rear cover <NUM> or shell at a coupled location. In one example, the coupled location can include a bolted joint, a welded joint, or any other type of coupling means. The converter <NUM> includes a turbine assembly <NUM> with turbine blades, a shell, and a core ring. The converter <NUM> also includes a pump assembly <NUM> with impellor or pump blades, an outer shell, and a core ring.

A stator assembly <NUM> is axially disposed between the pump assembly <NUM> and the turbine assembly <NUM>. The stator assembly <NUM> can include a housing, one or more stator blades, and a one-way clutch <NUM>. The one-way clutch <NUM> may be a roller or sprag design as is commonly known in the art.

The torque converter <NUM> includes a clutch assembly <NUM> that transmits torque from the front cover <NUM> to a turbine hub <NUM>. The clutch assembly <NUM> includes a piston plate <NUM>, a backing plate <NUM>, a plurality of clutch plates <NUM>, and a plurality of reaction plates <NUM>. The plurality of clutch plates <NUM> and reaction plates <NUM> can be splined to the turbine hub <NUM>, which is bolted to a turbine assembly as shown in <FIG>. The piston plate <NUM> can be hydraulically actuated to engage and apply the clutch assembly <NUM>, thereby "hydraulically coupling" the turbine assembly <NUM> and pump assembly <NUM> to one another. Hydraulic fluid can flow through a dedicated flow passage in the torque converter <NUM> on a front side of the piston plate <NUM> to urge the plate <NUM> towards and into engagement with the clutch assembly <NUM>. One skilled in the art can appreciate how this and other designs of fluid-coupling devices can be used for fluidly coupling an engine and transmission to one another.

Referring now to <FIG>, an embodiment is shown of a top half, cross-sectional view of a torque converter <NUM>. Torque converter <NUM> includes a front cover <NUM> coupled to a rear cover <NUM> or shell at a coupling location. In one example, the coupled location can include a bolted joint, a welded joint, or any other type of coupling means. The torque converter <NUM> includes a turbine assembly <NUM> having turbine blades, a shell, and a core ring. The torque converter <NUM> also includes a pump assembly <NUM> with impellor or pump blades, an outer shell, and a core ring.

The torque converter <NUM> includes a clutch assembly <NUM> that transmits torque from the front cover <NUM> to a turbine hub <NUM>. The turbine hub <NUM> may further be splined or otherwise coupled to a turbine shaft of a transmission (not shown). The clutch assembly <NUM> includes a piston <NUM> disposed within a cavity created by the front cover <NUM>. The piston <NUM> may have a radial protrusion <NUM> that is defined radially about the piston <NUM> and protrudes partially towards the rear cover <NUM>. At least one clutch plate <NUM> (referred to as "first portion" in the claims) and at least one reaction plate <NUM> (referred to as "second portion" in the claims) may also be disposed within the cavity. The clutch plate <NUM> and the reaction plate <NUM> may be radially disposed to axially adjacent to the protrusion <NUM> of the piston <NUM>. Additionally a backing plate <NUM> is also disposed within the cavity created by the front cover <NUM> at a location that permits the backing plate <NUM> to be substantially adjacent to the clutch plate <NUM> and/or the reaction plate <NUM>.

The clutch assembly <NUM> is coupled to the turbine hub <NUM> through a damper <NUM>. The damper <NUM> may provide for damping torque variations experienced between the front cover <NUM> and the turbine hub <NUM> as is known in the art. One of ordinary skill in the art may be familiar with the plurality ways the torque load distribution in a torque converter can be damped, and this invention is not be limited to any one type of damper. For example, a coil spring may be used to rotationally couple two components to one another. When a torsional load is distributed from one component to the other, the spring may provide a damped transmission of the torsional load. Additionally, any other type of damping system can be used. Damping systems such as hydraulic shock absorbers, gas springs, clutch assemblies, and the like are considered and this invention is not limited to any particular type of damper.

The piston <NUM> can be hydraulically actuated to engage and apply the clutch assembly <NUM>, thereby mechanically coupling the turbine assembly <NUM> and front cover <NUM> to one another. Fluid can flow through a dedicated flow passage in the torque converter <NUM> on a front side of the piston <NUM> to urge the piston <NUM> towards, and into engagement with, the clutch assembly <NUM>. One skilled in the art can appreciate how this and other designs of clutch assemblies can be used for mechanically coupling two rotating components to one another.

According to the invention, the backing plate <NUM> is supported by a first member <NUM> (referred to as "first plate" in the claims) and a second member <NUM> (referred to as "second plate" in the claims) is shown in <FIG>. The first member <NUM> and the second member <NUM> can be used to transfer torsional loads from the front cover <NUM> to the turbine hub <NUM> when the clutch assembly <NUM> is in the engaged position. In one nonlimiting example, when the clutch is engaged, the torque applied to the front cover <NUM> may be transferred into the nose hub <NUM> (referred to as "front cover hub" in the claims). The nose hub <NUM> may be fixedly coupled to the first and second member <NUM>, <NUM> and transfer the applied torque through the clutch assembly <NUM>, down the damper <NUM>, and into the turbine hub <NUM>.

More specifically, the first member <NUM> may be coupled to the backing plate <NUM> at a radially outer location of the backing plate <NUM>, while the second member <NUM> may be coupled to the backing plate <NUM> at a radially inner location of the backing plate <NUM>. Alternatively, the backing plate <NUM> may be a continuation of, or integrally formed with, the second member <NUM>.

The first member <NUM> may be substantially annular in shape with a central hole or bore therethrough. Further, the first member <NUM> may have an arc-shaped cross section as shown in <FIG>. The arc-shaped cross section may be coupled at one end to the backing plate <NUM> and coupled at the other end to the second member <NUM>.

The second member <NUM> may also be annular and be formed with a plurality of bends when viewed in the cross section of <FIG>. The second member <NUM> may form the backing plate <NUM> and terminate at a backing plate lip <NUM> (referred to as "outer lip" in the claims). The second member <NUM> has also at least one finger <NUM> that engage the splines of the clutch plate <NUM>.

Now referring to <FIG>, an isolated view of a piston <NUM> is shown. In one embodiment of the present invention, the piston <NUM> may be located partially along one end of the clutch assembly <NUM> as shown in <FIG>. The piston <NUM> may have a protrusion <NUM> that is defined radially in the piston <NUM>. The protrusion <NUM> may also align at least partially with the clutch assembly <NUM>. The protrusion <NUM> can extend sufficiently away from a planar surface <NUM> of a piston plate <NUM> so a portion of the protrusion <NUM> will contact the clutch assembly <NUM> when the piston <NUM> is disposed in the engaged position.

The piston <NUM> may have an inner sleeve <NUM> and an outer sleeve <NUM>. The inner sleeve <NUM> may have an inner radius that is slightly greater than an outer radius of an internal portion <NUM> of a nose hub <NUM> as shown in <FIG>. The radius of the inner sleeve <NUM> may be sufficiently large to allow the piston <NUM> to slide axially along the internal portion <NUM> of the nose hub <NUM> while simultaneously being able to substantially restrict fluid from passing between the inner sleeve <NUM> and the nose hub <NUM>. To further limit fluid transfer through the inner sleeve <NUM>, a first seal <NUM> may be located between the inner sleeve <NUM> and the internal portion <NUM> of the nose hub <NUM>.

The outer sleeve <NUM> may have an outer radius that is slightly less than an inner portion <NUM> of the front cover <NUM> as shown in <FIG>. The outer radius of the outer sleeve <NUM> may be adequately sized to allow the piston <NUM> to slide axially along the inner portion <NUM> of the front cover <NUM> while simultaneously being tight enough to substantially restrict fluid from passing between the inner portion of the front cover <NUM> and the outer sleeve <NUM>. To further limit fluid transfer through the outer sleeve <NUM>, a second seal <NUM> may be located between the outer sleeve <NUM> and the inner portion <NUM> of the front cover <NUM>.

The inner sleeve <NUM> and the outer sleeve <NUM> may be configured to allow the piston <NUM> to move both axially and radially about a first or rotation axis <NUM>. The axial movement of the piston <NUM> may be controlled by filling a piston plate cavity <NUM> with a pressurized fluid (not shown) via one or more of the fluid paths <NUM><NUM>-<NUM>J. As the piston plate cavity <NUM> is filled with fluid, the piston <NUM> may move axially away from the front cover <NUM>. As the piston <NUM> is forced away from the front cover <NUM>, the protrusion <NUM> in the piston <NUM> may contact the clutch assembly <NUM>. In turn, the clutch plate <NUM> and the reaction plate <NUM> may be forced into contact with one another sufficiently to transfer torsional loads between the front cover <NUM> and the turbine hub <NUM>. Further, when pressurized fluid is no longer supplied to the piston plate cavity <NUM>, the protrusion <NUM> may no longer provide sufficient axial force to the clutch assembly <NUM> to provide mechanical coupling between the front cover <NUM> and the turbine hub <NUM> through the clutch assembly <NUM>.

In one embodiment, the piston <NUM> is not required to transfer any torque to the clutch assembly <NUM>. In this embodiment, the first and second seal <NUM>, <NUM> may allow sufficient frictional properties between the piston <NUM>, the front cover <NUM>, and the nose hub <NUM> to rotate the piston <NUM> as the front cover rotates <NUM>. In a different embodiment, the frictional properties of the first and second seal <NUM>, <NUM> may allow the piston <NUM> to rotate independently of the front cover <NUM>. In yet another embodiment, the piston <NUM> may be radially coupled to either the front cover <NUM> or the nose hub <NUM>, or both, so that the piston <NUM> rotates as the front cover <NUM> rotates.

When the clutch assembly <NUM> is in the engaged or "lockup" position, the backing plate <NUM> may adequately counteract the axial force from the piston <NUM> to keep the backing plate <NUM> from substantially deflecting towards the rear cover <NUM>.

Now referring to <FIG>, one embodiment of a backing plate assembly <NUM> is shown. The backing plate assembly <NUM> may be radially defined about the first axis <NUM>. The backing plate assembly <NUM> can have the lip <NUM>, backing plate <NUM>, finger <NUM>, and second member <NUM> shown in <FIG>. The second member <NUM> includes at least one bend <NUM> radially formed about the first axis <NUM> to increase the rigidity of the backing plate assembly <NUM>. Further, the backing plate <NUM> may be substantially the same piece of material as the second member <NUM>. More specifically, as the second member <NUM> extends radially away from the first axis <NUM>, it may define the backing plate <NUM> by creating a substantially planar radial surface that is perpendicular to the first axis <NUM>.

Additionally, the finger <NUM> may be formed from a partially cutout portion of the backing plate <NUM>. More specifically, the finger <NUM> may be a cutout of a portion of the backing plate <NUM> that is bent towards the front cover <NUM> at a radial distance from the first axis <NUM> to create a substantially <NUM> degree bend from the surface of the backing plate <NUM>.

The second member <NUM> may have a lip <NUM> defined at a first end thereof about the radially innermost portion of the backing plate assembly <NUM>. The lip <NUM> may partially define a passage capable of allowing a shaft to pass therethrough. The backing plate assembly <NUM> may extend radially outward from the lip <NUM> to form a hub portion <NUM>. The hub portion <NUM> may be radially defined about the first axis <NUM> to correspond with the interior dimensions of the nose hub <NUM> (<FIG>). The hub portion <NUM> can be dimensioned to be received by a cavity created by the nose hub <NUM>. Further, the nose hub <NUM> can be disposed to substantially encompass the lip <NUM> and the remaining hub portion <NUM> of the backing plate assembly <NUM> as shown in <FIG>.

In one embodiment, the nose hub <NUM> can be used to couple the front cover <NUM> to the second member <NUM>. The nose hub <NUM> may be coupled to the front cover <NUM> at a coupling point <NUM> in a manner that is sufficient to transfer the torsional loads from the front cover to the nose hub <NUM>. In one embodiment, the front cover <NUM> may be welded to the nose hub <NUM> at the coupling point <NUM> but this invention is not limited to such a coupling method. One skilled in the art will understand how other coupling methods may be utilized to achieve similar results. Such methods as fasteners, adhesives, splines, threads, press fittings, and the like may be used to couple the nose hub <NUM> and the front cover <NUM> to one another.

The nose hub <NUM> may also be coupled to the backing plate assembly <NUM>. The backing plate assembly <NUM> may be press fit or otherwise disposed within the cavity created by the nose hub <NUM>. Additionally, the backing plate assembly <NUM> may also be coupled to the nose hub <NUM> utilizing one or more of the plurality of coupling methods described above. Once the torque converter <NUM> is fully assembled, torsional inputs into the front cover <NUM> may be distributed to the backing plate assembly <NUM> through the nose hub <NUM>.

Further, the backing plate assembly <NUM> can terminate at the backing plate lip <NUM> located at the radially outermost portion of the second member <NUM>. The backing plate lip <NUM> may be defined circumferentially about the outermost diameter or edge of the second member <NUM>. In addition, the lip <NUM> may be substantially perpendicular to the surface of the backing plate <NUM>. By terminating the backing plate <NUM> at the backing plate lip <NUM>, the stiffness of the backing plate assembly <NUM> may be improved. While one embodiment may utilize the backing plate lip <NUM> that is perpendicular to the backing plate <NUM>, this invention is not intended to be limited to such an orientation. One skilled in the art will understand how a plurality of different degree bends may also be utilized to achieve substantially the same result.

A cutaway view <NUM> of the backing plate assembly <NUM> is shown in <FIG>. More specifically, a first and second location <NUM>, <NUM> are shown as one non-limiting example of where the first member <NUM> may couple to the second member <NUM>. The first location <NUM> may be a radially inner portion of the first member <NUM> that is substantially adjacent with a portion of the second member <NUM>. The second location <NUM> may be a radially outer portion of the first member <NUM> that is substantially adjacent with a portion of the second member <NUM>. The first member <NUM> and the second member <NUM> can be coupled to one another in a plurality of ways such as welds, bolts, rivets, chemical bonding agents or the like. In one non-limiting aspect, the first location <NUM> and the second location <NUM> may substantially affix the first member <NUM> and the second member <NUM> to one another. In another aspect, the two members may not be fixed to one another.

The backing plate <NUM> may experience axial forces about the first axis <NUM> when the piston <NUM> engages the clutch assembly <NUM> as described above. By coupling the first member <NUM> to the second member <NUM> at the first and second locations <NUM>, <NUM>, the rigidity of the backing plate assembly <NUM> may be enhanced. More specifically, as the piston <NUM> applies the axial force to the backing plate <NUM>, the first member <NUM> may substantially inhibit any axial movement of the backing plate <NUM> by being coupled to the second member <NUM> at both the first and second location <NUM>, <NUM>.

When an axial force <NUM> (<FIG>) is applied by the piston <NUM>, the backing plate <NUM> may resist axial movement by transferring a resistive force <NUM> through the backing plate assembly <NUM> to the turbine hub <NUM>. Further, because the backing plate assembly <NUM> may resist axial movement at a radially inner portion <NUM>, it may be more susceptible to axial deflection about the radially outermost portion of the backing plate <NUM>. In one embodiment, the second location <NUM> may be a radially outermost portion of the backing plate <NUM> to substantially resist axial deflection about the backing plate <NUM>. By coupling the first member <NUM> to the second member <NUM> at such a second location <NUM>, the backing plate <NUM> may substantially resist deflection under the axial force <NUM> created by the piston <NUM>.

Referring back to <FIG>, the finger <NUM> is also more clearly shown. The finger <NUM> may be formed during the manufacturing process for the second member <NUM>. A plurality of fingers <NUM> may be spaced radially equidistant from one another to allow the engagement between each finger <NUM> and the reaction plate <NUM> or the clutch plate <NUM>. Each finger <NUM> can be sufficiently strong to transfer any radial forces from the input shaft <NUM> of the torque converter <NUM> through the damper <NUM> and into the turbine shaft <NUM> when the clutch assembly <NUM> is in the engaged position.

While one embodiment of the invention may have the plurality of fingers <NUM> equidistantly spaced from one another, one skilled in the art will understand how a plurality of offset distances may be used as well to achieve substantially the same result. Further, the number of fingers and the width of each finger may vary greatly depending on the particular load being transferred by each finger. As is known in the art, the particular design of the plurality of fingers <NUM> can be varied to accommodate the various loads that may need to be transferred therethrough.

The embodiment shown in <FIG> and <FIG> may be manufactured utilizing a stamping/punching process and a welding process. The first step of the manufacturing process may be stamping or punching the first member <NUM> out of a sheet of material. The sheet can be any desired material composition or otherwise and may be the appropriate thickness to resist substantial deformation. The stamping or punching process can take place either simultaneously or in different steps.

If the stamping or punching process is done in different steps, the needed material for the first member <NUM> can be punched out of the supplied material to create a blank. The blank can have the desired dimensions to correlate with the stamping process to create the desired final backing plate assembly <NUM> dimensions. In one non-limiting example, the blank for the first member <NUM> may have a diameter larger than the final diameter of the first member <NUM>. During the stamping process, the blank for the first member <NUM> may be formed into the desired final shape by pressing the blank between a die. The die may form the bend <NUM> into the first member <NUM>. Similarly to the above process described for the first member <NUM>, the second member <NUM> may undergo a punching or stamping process to achieve a desired final result.

After the first member <NUM> and the second member <NUM> have been formed, it may be necessary to couple the two pieces to one another to create an adequately strong backing plate assembly <NUM>. One method of coupling the first member <NUM> and the second member <NUM> to one another may include welding the two components to one another. A weld or welds may be located at both the first location <NUM> and the second location <NUM>. The weld or welds may be continuous throughout the first location <NUM> and the second location <NUM> of the first member <NUM>. The weld or welds may also be segmented throughout the first location <NUM> and the second location <NUM> of the first member <NUM>.

While methods for using a press have been described herein as a way to form the components of the backing plate assembly <NUM>, this invention is not limited to any particular manufacturing method. One skilled in the art will understand how a laser, waterjet, CNC mill, plasma cutter, and/or the like may be used to cut a material into a desired blank. Further, while a press and a die have been described as one way to create the desired shape of the backing plate assembly <NUM>, other methods such as molding, machining, <NUM>-D printing, additive manufacturing, casting or any other similar manufacturing process may be used.

While welding has been described as one method for coupling the first member <NUM> to the second member <NUM> other coupling methods may be used. More specifically, the two plates may be bolted, riveted, press fit, or otherwise coupled to one another and no single coupling method should be seen as limiting.

Another embodiment of the backing plate assembly <NUM> absent a lip is shown in <FIG> and <FIG>. In this embodiment, the backing plate <NUM> may terminate at a radial end that is planar with the surface of the backing plate <NUM>. A cross-section view <NUM> of the backing plate assembly <NUM> is shown in <FIG>. Similar to the embodiment shown in <FIG>, this embodiment may also have a first member <NUM> and a second member <NUM>. The first member <NUM> and the second member <NUM> may be substantially similar in shape to the first member <NUM> and the second member <NUM>, respectively, with the exception of the removed backing plate lip <NUM>.

In one embodiment, it may be advantageous to have the backing plate <NUM> terminate in a way that is planar to the backing plate <NUM> surface. The embodiment shown in <FIG> and <FIG> may allow for the backing plate <NUM> to be compatible with clutch assemblies of various dimensions. For example, in the backing plate assembly <NUM> of <FIG>, the clutch assembly <NUM> may need to be designed to fit within the backing plate <NUM> as defined by the backing plate lip <NUM>. In <FIG> and <FIG>, however, the backing plate is not bound along an external edge of the backing plate <NUM>.

A different example of a torque converter, which does not form part of the claimed invention, may have a single piece backing plate assembly <NUM>, as shown in <FIG> and <FIG>, instead of having a plurality of pieces coupled together to form the backing plate assembly. The backing plate assembly <NUM> may have at least one finger <NUM> that may extend at least partially outward from a planar surface <NUM> of the backing plate <NUM>. The finger <NUM> may be aligned along a radius that defines an inner radial edge of a backing plate <NUM>.

A cutaway view <NUM> of the backing plate assembly <NUM> is shown in <FIG>. The finger <NUM> may be formed as a substantially perpendicular bend from the planar surface <NUM> of the backing plate assembly <NUM>. More specifically, the finger <NUM> can be formed by cutting a partial profile of the finger <NUM> out of the backing plate <NUM> prior to making the substantially perpendicular bend.

One aspect of the example shown in <FIG> and <FIG> is that it may only require one manufacturing step. For example, a stamping process may form the single piece backing plate <NUM> in one step. One example of manufacturing the embodiment shown in <FIG> and <FIG> is first supplying a sheet of material having a desired thickness to a press. The press may then form the features of the single piece backing plate <NUM> by pressing the material into a die. A punching process may simultaneously be executed that can separate the single piece backing plate <NUM> from the excess material. The pressing step and the punching step may be performed either simultaneously or in any order, and this invention is not limited to any one method or particular order.

One advantage of the example shown in <FIG> and <FIG> is that the single piece backing plate <NUM> may be complete after the stamping or punching process. More specifically, the single piece backing plate <NUM> may be completed without welding or otherwise coupling multiple pieces to one another to form the backing plate <NUM>. Thus, the process is relatively simple and parts can be easily mass produced.

Yet another example of a torque converter, which does not form part of the claimed invention, is shown in <FIG> and <FIG>. Another backing plate assembly <NUM> is shown in <FIG> that is made of substantially one piece. The backing plate assembly <NUM> may include many of the features previously described such as a backing plate <NUM>, at least one finger <NUM>, at least one bend <NUM>, a shaft passage or bore <NUM>, and a hub portion <NUM>. The backing plate assembly <NUM> can function in substantially the same way as previous embodiments.

As illustrated by the cutaway portion <NUM> shown in <FIG>, the backing plate assembly <NUM> can be formed of one piece of material. The material can include a series of bends and cuts to allow it to be formed into the backing plate assembly <NUM> shown in <FIG>. The backing plate <NUM> may be formed by a <NUM> degree bend <NUM> at the outermost portion of the backing plate assembly <NUM>. There may be an approximately <NUM> degree bend <NUM> at a radially outermost section of each of a plurality of backing plate sections <NUM>. Each section <NUM> may define a portion of the backing plate <NUM> where the material of the backing plate assembly <NUM> is folded under the backing plate <NUM> surface to create a twofold layer of material. The backing plate sections <NUM> may be defined partially by at least one cutout <NUM> in the backing plate material. Additional cutouts <NUM> may be spaced radially around the backing plate assembly <NUM>.

The backing plate sections <NUM> may terminate about a radially outermost edge to create substantially straight exterior edges <NUM> of the backing plate assembly <NUM>. The straight exterior edges <NUM> may be angularly offset from one another so that they combine to create a substantially <NUM> degree sum. For example, there may be eight sections <NUM> that create a substantially octagonal circumference with their eight straight exterior edges <NUM>.

A portion of the cutout <NUM> may be utilized to form the finger <NUM>. Additionally, in one embodiment the finger <NUM> may be formed by a substantially <NUM> degree bend <NUM> of the backing plate <NUM>. Further, the bend <NUM> in the finger <NUM> may be a <NUM> degree bend at the distal portion of the finger <NUM> from the backing plate <NUM>. The bend <NUM> may terminate at a base <NUM> of the finger <NUM>. As a result of the <NUM> degree bend, the finger <NUM> may be comprised of a twofold layer of the backing plate assembly <NUM> material.

In one example of the finger <NUM>, a weld may be created along the base <NUM> of the finger <NUM>. The weld may add sufficient rigidity to the finger <NUM> to allow the backing plate assembly <NUM> to adequately transfer torsional loads from the clutch assembly <NUM> to the nose hub <NUM>. Additionally, a weld may be created along the sides of the finger <NUM> to further couple the two layers to one another. This too may be utilized to increase the load bearing capacity of the finger <NUM>.

In yet another example, the backing plate <NUM> may also include a weld or other means to increase the stiffness of the backing plate assembly <NUM>. The weld may be located along a backing plate edge terminus <NUM>. By locating the weld along the terminus <NUM>, the rigidity of the backing plate <NUM> can be increased by both the added reinforcement of the weld and by additional layers of the backing plate material in parallel alignment with one another.

Claim 1:
A torque converter (<NUM>; <NUM>) with a lockup clutch (<NUM>), comprising:
a front cover (<NUM>) extending from a front cover hub (<NUM>) and coupled to a rear cover (<NUM>);
a pump assembly (<NUM>) coupled to the rear cover (<NUM>);
a turbine assembly (<NUM>) coupled to a turbine hub (<NUM>);
a stator assembly (<NUM>) located between the turbine assembly (<NUM>) and the pump assembly (<NUM>);
a damper (<NUM>) coupled to the turbine hub (<NUM>) and defining damper clutch fingers;
a clutch assembly (<NUM>) coupled between the backing plate assembly (<NUM>) and the damper (<NUM>);
a piston (<NUM>) disposed in the front cover (<NUM>) between a front plane and the clutch assembly (<NUM>); and
a backing plate assembly (<NUM>) coupled to the front cover hub (<NUM>) and comprising:
a first plate (<NUM>; <NUM>) extending radially outward from a hub portion (<NUM>);
at least one finger (<NUM>) extending from the backing plate assembly (<NUM>; <NUM>) that engages a portion of the clutch assembly (<NUM>); and
a backing plate surface aligned with the clutch assembly (<NUM>);
wherein the backing plate assembly (<NUM>; <NUM>) provides axial resistance for the clutch assembly (<NUM>) and transfers torsional forces from the hub portion (<NUM>) to the clutch assembly (<NUM>), and
wherein the at least one finger (<NUM>) extending from the backing plate assembly (<NUM>; <NUM>) engages a first portion (<NUM>) of the clutch assembly (<NUM>) and the damper clutch fingers engage a second portion (<NUM>) of the clutch assembly (<NUM>),
characterized by
a second plate (<NUM>; <NUM>) coupled to the first plate (<NUM>; <NUM>) and extending radially outward from the hub portion (<NUM>); and
at least one bend (<NUM>) in each the first plate (<NUM>; <NUM>) and the second plate (<NUM>; <NUM>).