Patent Description:
This invention relates to a clutch system of the friction type placed in a power transmission system. Typical clutch systems include a clutch input such as a clutch basket, a clutch output such as a center clutch or clutch hub, and one or more plates making up a clutch pack and disposed between the clutch input and clutch output. When the clutch pack is compressed, the clutch input and clutch output become rotationally coupled. The clutch pack is typically compressed by a pressure plate; the pressure plate typically providing a compressive force via a spring mechanism or through a centrifugally actuated mechanism.

A clutch pack is typically made up of two types of plates-driving plates and driven plates. Driving plates are commonly referred to as friction discs and are coupled rotationally to a clutch basket. A clutch basket is typically coupled to an input from a motor. Driven plates are commonly referred to as separator plates and are coupled rotationally to a clutch hub. Separator plates are commonly constructed of steel. A clutch hub is typically coupled to an output such as a transmission. Typically, such clutch systems include a clutch disengagement system consisting of a clutch lever mechanically coupled to the pressure plate such that when the clutch lever is actuated, the pressure plate's compressive force on the clutch pack is removed, disconnecting the rotational coupling between the clutch input and clutch output. Clutch disengagement systems typically couple the clutch lever to the pressure plate mechanically through a hydraulic actuation system or a cable actuation system. The clutch system incorporated in a <NUM> Honda CRF-450R represents a typical prior art clutch system utilizing a clutch cable and a cast aluminum clutch hub. The clutch system incorporated in a <NUM> KTM <NUM> XC-F represents a prior art clutch system utilizing a hydraulic actuation system and a clutch hub paired with moveable drive pins.

Most motorcycles incorporate a manual transmission coupled to the engine via a multi-plate clutch assembly. Typically, the multi-plate clutch is engaged/disengaged by the driver via a clutch lever mounted on the handlebar. The clutch lever operated clutch allows the driver to control the clutch engagement/disengagement. When clutch components are in good working condition, clutch lever use and feel is normal and not compromised.

A center clutch, or clutch hub, is typically formed from aluminum and is one piece where internal cutouts within a separator plate are formed to provide coupling engagement to corresponding features directly formed into the clutch hub. The aluminum construction of a clutch hub is generally preferred because aluminum is of relatively light weight while maintaining adequate strength for carrying the torque load transmitted through a clutch hub. A downside to these types of clutch hubs constructed of aluminum providing aluminum on steel contact between the hub and separator plate is that the cutouts or teeth of the separator plate can wear the corresponding surfaces in the hub they are coupled to. This wear can result in grooves or notches being formed and can cause the separator plates to bind to the hub making the operation of the clutch lever to override the clutch suboptimal. In extreme cases the clutch can drag excessively even when the clutch lever is activated fully not allowing for complete disengagement of the engine from the transmission.

In the <NUM> KTM <NUM> XCF, an aluminum hub is paired with moveable drive pins cylindrical in shape where the drive pins are coupled to the clutch hub. The drive pins are also coupled to corresponding cutouts within a separator plate. Typically the drive pins are formed of steel thus providing a more wear resistant contact surface for the cutouts within the separator plates to drive against. In these configurations the moveable drive pins transmit the torque load from the separator plates to the clutch hub.

The coupling between the hub and moveable drive pins is usually achieved utilizing coupling features comprised of an oversized circular slot extending axially from the open end of the hub to the base flange of the hub terminating into an oversized counter-bored hole extending from the slot into the base flange of the hub where the oversized counter-bored hole is of the same diameter and on the same center as the oversized circular slot. The drive pins are placed with one end locating into the oversized counter-bored hole and the body of the drive pin extending within and along the slot. The drive pin extends above the open end of the hub. The bottom of the oversized counter-bored hole limits the drive pins in an axial direction toward the base flange. The fit between the drive pins and coupling features is considered a loose slide fit allowing the drive pins to freely move in an axial direction parallel to the oversized circular slot. The drive pins are also free to move radially away from the center of the hub under centrifugal force limited by the outer diameter of the pin coming into tangent contact with the wall for the oversized counter-bored hole. Lastly, the drive pins are also free to rotate within the oversized circular slot and oversized counter-bored hole. The pressure plate utilized with a hub of this type contains a feature limiting the movement of the pins axially in the direction away from the base flange. The limiting feature in the pressure plate does not contact the end of the drive pin unless the drive pin slides along the oversized circular slot toward the pressure plate. Although the moveable drive pins provide steel on steel contact with the separator plates disadvantages exist from the drive pins being moveable axially and radially relative to the coupling features within the hub. One disadvantage is the wear which takes place between the drive pins, circular slot and counter-bore from the movement of the drive pins. Torque loads can be applied and reversed rapidly due to shock loads imparted on the drive train of the vehicle. These shock loads are caused by rapid acceleration or deceleration of the motor driving the clutch, or from events causing sudden stoppage of the drive train such as landing from a jump at high speeds. The shock loads impart an impact load on the pin which in turn transmits an impact load on the hub causing wear to the circular slot and counter-bored hole. As the circular slot and counter-bored hole wears the movement of the pin can become greater thus further amplifying the impact loads transmitted from the separator plates. In addition the movement described of the drive pins can also allow the separator plates to oscillate further out of center relative to the hub center resulting in clutch noise and as the user re-engages the clutch through the disengagement mechanism. <CIT>discloses a clutch hub assembly including drive elements for use in a clutch. The clutch having a clutch basket with fingers and slots and a stack of a series of alternating driving discs and driven discs positioned in the clutch basket. The clutch basket is rotationally coupled to the driving discs such that rotational output of the engine of a motor vehicle is transmitted to the clutch basket and the driving discs. A clutch hub is positioned within the clutch basket. The clutch hub is configured for selective coupling to the clutch basket through the driven plates such that rotation of the driven plates causes rotation of the clutch hub. The stack of alternating driving discs and driven discs are configured to transmit rotation from the driving discs to the driven discs in response to pressure from a pressure plate providing compression of the stack of driving and driven discs. The pressure plate provides compression to the stack of driving discs and driven discs frictionally coupling rotation of the driving discs to the driven discs and thus to the clutch hub. The clutch hub is rotationally coupled to an output. The pressure plate is configured for selective disengagement with the stack of alternating driven plates and drive plates such that disengaging the pressure plate releases the pressure on the stack of alternating driven plates and drive plates and thus frictionally decouples the clutch basket from the clutch hub. The hub assembly has a series of drive members that are positioned on the clutch basket. The drive members engage the driving disks to transmit the rotational movement of the clutch basket to the driving disks. The drive members are held in recesses in the clutch basket and are able to rotate around their own axes and to slide longitudinally in the clutch basket. Linhuber states in one embodiment the drive elements directly transfer rotational energy between the clutch basket and clutch hub. In this embodiment the rotational and sliding movement of the drive members is to allow stress-free movement of the driver elements and resulting on the one hand in an optimal contact pattern within the gearing system, and on the other hand in a distinct improvement in modulation of the clutch. In another embodiment the driver elements transfer the rotational energy via contact between the driving plates transferred to the driven plates in a compression state. In this embodiment the rotational and lateral movement of the drive members provides a positive connection between the drive elements and the driving discs. Thus Linhuber discloses drive elements that are rotationally free and able to slide in the clutch basket in either embodiment to allow for the reduced thickness of the pressure discs. <CIT> discloses a clutch having a clutch basket and a clutch hub. The clutch hub has a series of pins. The pins are not disclosed as having a feature being matingly engaged with the pins or a retaining mechanism to retain the pins in place. The reference further does not teach a clutch hub having a profiled ring. <CIT> similarly discloses a clutch having a clutch basket and a clutch hub. The clutch hub has a series of pins. The pins are not disclosed as having a feature being matingly engaged with the pins or a retaining mechanism to retain the pins in place. The reference further does not teach a clutch hub having a profiled ring.

Therefore a need exists for a clutch hub with a profiled ring having non-moveable liners able to couple with clutch separator plates wherein the liners are fixed axially and radially to the hub providing non-moveable contact with separator plates.

It is therefore an object of the present invention to provide an improved clutch hub assembly to minimize hub wear from contact with separator plates while also improving the engagement and disengagement characteristics (clutch lever feel and/or modulation) the rider experiences when using the clutch lever to manually engage and disengage the clutch.

The purpose of the Summary is to enable the public, and especially the scientists, engineers, and practitioners in the art who are not familiar with patent or legal terms or phraseology, to determine quickly from a cursory inspection, the nature and essence of the technical disclosure of the application. The Summary is neither intended to define the inventive concept(s) of the application, which is measured by the claims, nor is it intended to be limiting as to the scope of the inventive concept(s) in any way.

The disclosed technology is an improved clutch hub assembly having an improved clutch hub having a profiled ring and comprising a feature configured for mating engagement with a drive member, and a retaining mechanism for connecting the drive member to the feature such that drive members are non-moveable relative to the clutch hub body. The drive member rotationally couples the driven plate of the clutch to the improved clutch hub. This improved clutch hub assembly is designed to work in a clutch, such as those that are used in motorcycles. These types of clutches have a clutch basket, a clutch pack, a center clutch, and a pressure plate. The clutch basket being coupled to an input and the center clutch being coupled to an output. When the clutch pack is compressed by the pressure plate, the clutch basket and clutch club become rotationally coupled. The clutch pack is compressed by the pressure plate; the pressure plate provides a compressive force via a spring mechanism or through a centrifugally actuated mechanism. A clutch pack is made up of two types of plates-driving plates and driven plates. Driving plates are commonly referred to as friction discs and are coupled rotationally to a clutch basket. Driven plates are commonly referred to as separator plates and are coupled rotationally to the center clutch. Optionally, the driving plates can be formed without friction material and the friction material can be attached to the driven plates. The clutch basket has fingers and slots between the fingers. The clutch basket is operatively attached to the motorcycle motor. The clutch hub is operatively attached to the motorcycle transmission, and eventually to the wheel. The disclosed technology is an improved clutch hub assembly for placement within a clutch. The clutch system includes a clutch disengagement system consisting of a clutch lever mechanically coupled to the pressure plate such that when the clutch lever is actuated, the pressure plate's compressive force on the clutch pack is removed, disconnecting the rotational coupling between the clutch input and clutch output.

The disclosed improved clutch hub assembly including a profiled ring and at least one feature for locating and attaching a drive member, including a wear liner, to the clutch hub such that drive members are non-moveable relative to the clutch hub body. Furthermore, the drive members provide features for coupling and accepting torque loads from separator plates, also known as driven plates, within a clutch pack; in turn the wear liners or drive members will transmit the torque loads from the separator plates to the clutch hub body. The drive members are generally cylindrically shaped at one end with a substantial portion for the wear liner comprising a semi-circular cross-section continuing to the opposite end of the wear liner.

Optionally, cylindrical shaped drive members are pressed into undersized counter-bored holes within the flange of the clutch hub body while the opposite end of the drive members are clamped in place using a threaded fastener with clamping washer. The clamping washer having features which bias the drive member against the floor of the undersized counter-bored hole while also securing drive member such that it cannot rotate or move outward radially away from the axial center of the clutch hub body.

In another embodiment, non-round drive members are fastened to the clutch hub body utilizing cross-drilled and threaded holes formed into the non-round drive members and a threaded fastener such as a machine screw. In this embodiment the clutch hub contains features to support the non-round drive member along the axial direction of the clutch hub and length of the drive member.

Optionally, the drive member is comprised of a wear liner being a generally u-shaped strip formed with flanges on either vertical legs where the liner slides into corresponding grooves formed into the clutch hub body; where the liner covers vertical wall features formed into the clutch hub body.

Still other features and advantages of the presently disclosed and claimed inventive concept(s) will become readily apparent to those skilled in this art from the following detailed description describing preferred embodiments of the inventive concept(s), simply by way of illustration of the best mode contemplated by carrying out the inventive concept(s). As will be realized, the inventive concept(s) is capable of modification in various obvious respects all without departing from the inventive concept(s). Accordingly, the drawings and description of the preferred embodiments are to be regarded as illustrative in nature, and not as restrictive in nature.

Clutch hubs or center clutches are well known in the art and are typified by those used in clutches found in motorcycles and ATV's produced by Honda, KTM, Yamaha, Kawasaki and Suzuki among others.

A clutch hub is used within a typical clutch system comprised of a clutch input such as a clutch basket, a clutch output such as a clutch hub, a pressure plate and one or more disks making up a clutch pack and disposed between the clutch input and clutch output. When the clutch pack is compressed, the clutch input and clutch output become rotationally coupled. Such clutch systems typically include a clutch disengagement system consisting of a clutch lever mechanically coupled to the pressure plate such that when the clutch lever is actuated, the pressure plate's compressive force on the clutch pack is removed, disconnecting the rotational coupling between the clutch input and clutch output. Clutch disengagement systems typically couple the clutch lever to the pressure plate mechanically through a hydraulic actuation system or a cable actuation system.

The present invention provides for a novel, improved clutch hub assembly utilizing fixed wear liners or drive members attached to the clutch hub to provide coupling between at least one separator plate and said hub such that said separator plate can transmit torque loads through said drive member to said clutch hub without the position of said drive member changing relative to said clutch hub. Multiple embodiments are disclosed.

<FIG> is an exploded view of a prior art clutch. The configuration of the clutch basket <NUM>, clutch hub thrust washer <NUM>, clutch hub <NUM>, transmission input shaft <NUM>, clutch hub nut <NUM>, throw-out <NUM>, throw-out rod <NUM>, friction disk <NUM>, separator plate <NUM>, pressure plate <NUM>, standard springs <NUM> and spring bolts <NUM> are typical of most modern motorcycle clutches, this structure is commonly employed in many types of power transmission devices. Clutch pack <NUM> is comprised of friction disks <NUM> and separator plates <NUM>. The clutch basket <NUM> contains slots <NUM> which receive the friction disk tabs <NUM> and thus coupling the clutch basket <NUM> and friction disks <NUM> rotationally. The clutch hub <NUM> contains a profiled ring <NUM> which provides rotational coupling to the teeth <NUM> of the separator plates <NUM>. The clutch basket <NUM> is typically coupled rotationally to a power input source such as an engine and the clutch hub <NUM> is typically coupled rotationally to an output such as a transmission through a transmission input shaft <NUM>. In another embodiment the clutch basket <NUM> is coupled rotationally to an output and the clutch hub <NUM> is coupled rotationally to a power input. Typically the clutch basket <NUM> contains an opening in the center for receiving a transmission input shaft <NUM>; the clutch basket <NUM> is configured with a bearing between the clutch basket <NUM> and the transmission input shaft so that the clutch basket <NUM> can rotate independently of the transmission input shaft with minimal friction. Typically a clutch hub thrust washer <NUM> is disposed between a clutch hub <NUM> and the clutch basket <NUM>. A clutch hub nut <NUM> secures the clutch hub <NUM> against the clutch hub thrust washer <NUM> which in turn is secured against a shoulder (not shown) on the transmission input shaft <NUM>. The clutch hub is typically rotationally coupled to the transmission input shaft <NUM> via a suitable spline.

<FIG> is a section view of the prior art clutch shown in <FIG>. As best seen in <FIG>, the clutch pack <NUM> is comprised of eight friction disks <NUM> and seven separator plates <NUM>. The clutch pack <NUM> establishes the distance between the pressure plate flange face <NUM> and clutch hub flange face <NUM>. The standard springs <NUM> act on the pressure plate <NUM> to compress the clutch pack <NUM> forcing the adjacent surfaces of the friction disks <NUM> and separator plates <NUM> to become coupled rotationally and in turn coupling the basket <NUM> and clutch hub <NUM> rotationally. The throw-out <NUM> is coupled to a throw-out rod <NUM>. The throw-out rod <NUM> is coupled to a clutch disengagement system (not shown). The clutch disengagement system (not shown) is operable to selectively position the throw-out rod <NUM> and throw-out <NUM> for the purpose of pushing the pressure plate <NUM> away from the clutch pack <NUM> to disengage the clutch. Alternatively, the clutch disengagement system (not shown) is operable to selectively position the throw-out rod <NUM> and throw-out <NUM> for the purpose of returning the pressure plate <NUM> into contact with the clutch pack <NUM> to engage the clutch. In another embodiment the clutch pack <NUM> is comprised of nine friction disks <NUM> and eight separator plates <NUM>. In the preferred embodiment the clutch pack <NUM> is comprised of eight <NUM>-millimeter thick friction disks <NUM> and seven <NUM>-millimeter separator plates <NUM> resulting in the clutch pack <NUM> being approximately <NUM>-millimeters tall. In other prior art the clutch pack <NUM> is less than <NUM>-millmeters tall and is comprised of eight friction disks and seven separator plates that are less than <NUM>-millimeters thick. In yet other prior art, the clutch pack <NUM> is taller than <NUM> millimeters and is comprised of nine friction disks which are approximately <NUM>-millimeters thick and eight separator plates which are approximately <NUM>-millimeters thick.

<FIG> is an isometric view of the clutch hub <NUM> and a separator plate <NUM> showing the rotational coupling between the profiled ring <NUM> and the teeth <NUM> of the separator plate <NUM>.

<FIG> is an exploded view of an alternative prior art clutch utilizing a clutch hub <NUM> with moveable drive pins <NUM>. The drive pins <NUM> are cylindrical in shape. The configuration of the clutch basket <NUM>, clutch hub thrust washer <NUM>, clutch hub <NUM>, transmission input shaft <NUM>, clutch hub nut <NUM>, throw-out <NUM>, throw-out rod <NUM>, friction disk <NUM>, separator plate <NUM>, pressure plate <NUM>, springs <NUM> and spring bolts <NUM>. Clutch pack <NUM> is comprised of friction disks <NUM> and separator plates <NUM>. The clutch basket <NUM> contains slots <NUM> which receive the friction disk tabs <NUM> and thus coupling the clutch basket <NUM> and friction disks <NUM> rotationally. The clutch hub <NUM> contains a profiled ring <NUM> containing semi-circular slots <NUM>. The semi-circular slots <NUM> terminate in the flange <NUM> resulting in counter-bored hole <NUM> being formed into the flange <NUM> of the clutch hub <NUM>. The semi-circular slots <NUM> and counter-bored hole <NUM> are of equal diameter and are of larger diameter than the outer diameter of the pins <NUM>. The pins <NUM> provide rotational coupling to the cutouts <NUM> of the separator plates <NUM>. The clutch basket <NUM> is typically coupled rotationally to a power input source such as an engine and the clutch hub <NUM> is typically coupled rotationally to an output such as a transmission through a transmission input shaft <NUM>. In another embodiment the clutch basket <NUM> is coupled rotationally to an output and the clutch hub <NUM> is coupled rotationally to a power input. Typically the clutch basket <NUM> contains an opening in the center for receiving a transmission input shaft <NUM>; the clutch basket <NUM> is configured with a bearing between the clutch basket <NUM> and the transmission input shaft <NUM> so that the clutch basket <NUM> can rotate independently of the transmission input shaft <NUM> with minimal friction. Typically a clutch hub thrust washer <NUM> is disposed between a clutch hub <NUM> and the clutch basket <NUM>. A clutch hub nut <NUM> secures the clutch hub <NUM> against the clutch hub thrust washer <NUM> which in turn is secured against a shoulder (not shown) on the transmission input shaft <NUM>. The clutch hub is typically rotationally coupled to the transmission input shaft <NUM> via a suitable spline <NUM>.

<FIG> is a section view of the prior art clutch shown in <FIG>. As best seen in <FIG>, the pins <NUM> are contained within the semi-circular slots <NUM> and counter-bored hole <NUM> of the clutch hub <NUM>. The pressure plate <NUM> contains a second counter-bored hole <NUM> which is configured to receive one end of a pin <NUM> similar to the counter-bored hole <NUM> of the clutch hub <NUM>. The second counter-bored hole is of larger diameter than the outer diameter of the pin <NUM>. The clutch pack <NUM> is comprised of seven friction disks <NUM> and eight separator plates <NUM>. The clutch pack <NUM> establishes the distance between the pressure plate flange face <NUM> and clutch hub flange face <NUM>. The springs <NUM> act on the pressure plate <NUM> to compress the clutch pack <NUM> forcing the adjacent surfaces of the friction disks <NUM> and separator plates <NUM> to become coupled rotationally and in turn coupling the basket <NUM> and clutch hub <NUM> rotationally. With the pressure plate <NUM> in the position shown, the floor <NUM> of the counter-bored hole <NUM> and the second floor <NUM> of the second counter-bored hole <NUM> are separated by a distance which is longer than the pin <NUM> allowing the pin <NUM> to float axially in the directions parallel to line <NUM> and line <NUM>. The throw-out <NUM> is coupled to a throw-out rod <NUM>. The throw-out rod <NUM> is coupled to a clutch disengagement system (not shown). The clutch disengagement system (not shown) is operable to selectively position the throw-out rod <NUM> and throw-out <NUM> for the purpose of pushing the pressure plate <NUM> away from the clutch pack <NUM> to disengage the clutch. Alternatively, the clutch disengagement system (not shown) is operable to selectively position the throw-out rod <NUM> and throw-out <NUM> for the purpose of returning the pressure plate <NUM> into contact with the clutch pack <NUM> to engage the clutch. In another embodiment the clutch pack <NUM> is comprised of eight friction disks <NUM> and nine separator plates <NUM>. In the preferred embodiment the clutch pack <NUM> is comprised of eight <NUM>-millimeter thick friction disks <NUM> and nine <NUM>-millimeter separator plates <NUM> resulting in the clutch pack <NUM> being approximately <NUM>-millimeters tall. In other prior art the clutch pack <NUM> is less than <NUM>-millmeters tall and is comprised of eight <NUM>-millimeter thick friction disks and nine <NUM>-millimeter thick separator plates.

<FIG> is an isometric view of the clutch hub <NUM> with drive pins <NUM> and a separator plate <NUM> to show the rotational coupling between the profiled ring <NUM> and drive pin <NUM>, specifically showing how each drive pin <NUM> is installed within a semi-circular slot <NUM> and a counter-bored hole <NUM>, while also showing how each drive pin <NUM> is rotationally coupled to a cutout <NUM> of the separator plate <NUM>. <FIG> identifies that the drive pin <NUM> is cylindrically shaped with through-hole <NUM> and outer diameter <NUM>. In another embodiment the drive pin <NUM> is solid and does not contain through hole <NUM>.

<FIG> depicts an exploded view of the preferred embodiment clutch hub assembly <NUM> including a clutch hub <NUM>, sleeve <NUM> and hold-down screw <NUM>. The clutch hub <NUM> includes a profiled ring <NUM>, flange <NUM>, drive dowels <NUM>, sleeve holes <NUM> and seating shelf <NUM>. The drive dowel <NUM> has a generally cylindrical shape with a threaded hole <NUM> and a top <NUM>. The seating shelf <NUM> is formed into the top <NUM>. The clutch hub also includes a transition <NUM> between the drive dowel <NUM> features and profiled ring <NUM>. Each sleeve hole <NUM> is placed such that the center of the sleeve hole <NUM> is on the same center as the center of the drive dowel <NUM>. The sleeve <NUM> is comprised with a closed end <NUM>, an open end <NUM>, seating surface <NUM> vertical edges <NUM> and inner bore <NUM>. The closed end <NUM> forms a complete cylinder shape. The inner bore <NUM> allows the sleeve <NUM> to slide over the drive dowel <NUM>. In an alternate embodiment, the inner bore <NUM> has a diameter slightly smaller than the diameter of the drive dowel <NUM> requiring the sleeve <NUM> to be pressed over the drive dowel <NUM>. The sleeve hole <NUM> has a working diameter slightly larger than the outer diameter of the sleeve <NUM> allowing the open end <NUM> to be passed into the sleeve hole <NUM>. In an alternate embodiment the sleeve hole <NUM> has a working diameter slightly smaller than the outer diameter of the sleeve <NUM> requiring the open end <NUM> to be pressed into the sleeve hole <NUM> when it is positioned over the drive dowel <NUM>.

<FIG> and <FIG> show the preferred embodiment clutch hub assembly <NUM> with the sleeves <NUM> installed over the drive dowels <NUM> of the clutch hub <NUM>. The hold-down screws <NUM> affix the sleeves <NUM> to the clutch hub <NUM>. As shown in <FIG> and <FIG> the cutout <NUM> of the separator plate <NUM> is rotationally coupled to the sleeve <NUM>.

As best seen in <FIG>, the open end <NUM> of the drive dowel <NUM> is placed into the sleeve hole <NUM>. The closed end <NUM> is fitted over the top <NUM> of the drive dowel <NUM>. The seating surface <NUM> of the sleeve <NUM> is positioned against the seating shelf <NUM> of the clutch hub <NUM>. The hold-down screw <NUM> is threaded into the threaded hole <NUM>. When the hold-down screw <NUM> is tightened the backside <NUM> of the screw head <NUM> applies a compressive force to the top of the closed end <NUM> driving the seating surface <NUM> against the seating shelf <NUM> resulting in locking the sleeve <NUM> in the inward direction <NUM> and outward direction <NUM> parallel to center axis <NUM>. In another embodiment a washer is used between the hold-down screw <NUM> and closed end <NUM>. The inner bore <NUM> of the closed end <NUM> with the working diameter of the top <NUM> prevent the sleeve <NUM> from moving radially in a direction perpendicular to center axis <NUM> away from the drive dowel <NUM>. Similarly, the outer diameter of the sleeve <NUM> near the open end <NUM>, with the sleeve hole <NUM>, prevents the sleeve <NUM> from moving radially in a direction perpendicular to center axis <NUM> away from the drive dowel <NUM>. When the screw <NUM> is not tightened fully the sleeve <NUM> is free to rotate slightly about the center of the drive dowel <NUM> until a vertical edge <NUM> contacts the transition <NUM>. In an alternative embodiment the transition <NUM> is formed such that to provide an interference fit between the transition <NUM> and vertical edges <NUM> requiring the sleeve <NUM> to be pressed into the position shown in <FIG> resulting in the sleeve <NUM> being rotationally locked relative to the center of the drive dowel <NUM>.

<FIG> depicts and exploded view of the preferred embodiment clutch hub assembly <NUM> configured within a multi-plate clutch assembly <NUM>. The multi-plate clutch assembly shown in <FIG> shares similar characteristics to the multi-plate clutch assemblies previously disclosed in <FIG>. The multi-plate clutch assembly <NUM> includes a clutch basket <NUM>, clutch hub thrust washer <NUM>, clutch hub assembly <NUM>, transmission input shaft <NUM>, clutch hub nut <NUM>, throw-out <NUM>, throw-out rod <NUM>, friction disk <NUM>, separator plate <NUM>, pressure plate <NUM>, standard springs <NUM>, spring bolts <NUM> and spring locators <NUM>. Clutch pack <NUM> is comprised of friction disks <NUM> and separator plates <NUM>. The clutch basket <NUM> contains slots <NUM> which receive the friction disk tabs <NUM> and thus coupling the clutch basket <NUM> and friction disks <NUM> rotationally. The clutch hub assembly <NUM> couples to the separator plate <NUM> via the sleeves <NUM> and cutouts <NUM> of the separator plate <NUM>. The clutch basket <NUM> is typically coupled rotationally to a power input source such as an engine and the clutch hub assembly <NUM> is typically coupled rotationally to an output such as a transmission through a transmission input shaft <NUM>. In another embodiment the clutch basket <NUM> is coupled rotationally to an output and the clutch hub assembly <NUM> is coupled rotationally to a power input. The clutch basket <NUM> contains an opening in the center for receiving the transmission input shaft <NUM>; the clutch basket <NUM> is configured with a bearing (not shown) between the clutch basket <NUM> and the transmission input shaft <NUM> so that the clutch basket <NUM> can rotate independently of the transmission input shaft <NUM> with minimal friction. The clutch hub thrust washer <NUM> is disposed between the clutch hub assembly <NUM> and the clutch basket <NUM>. A clutch hub nut <NUM> secures the clutch hub assembly <NUM> against the clutch hub thrust washer <NUM> which in turn is secured against a shoulder (not shown) on the transmission input shaft <NUM>. The clutch hub assembly <NUM> is rotationally coupled to the transmission input shaft <NUM> via a suitable spline <NUM>.

<FIG> is a section view of the prior art clutch shown in <FIG>. As best seen in <FIG>, the clutch pack <NUM> is comprised of ten friction disks <NUM> and eleven separator plates <NUM>. The clutch pack <NUM> establishes the distance between the pressure plate flange face <NUM> and clutch hub flange face <NUM>. The standard springs <NUM> act on the pressure plate <NUM> to compress the clutch pack <NUM> forcing the adjacent surfaces of the friction disks <NUM> and separator plates <NUM> to become coupled rotationally and in turn coupling the basket <NUM> and clutch hub assembly <NUM> rotationally. The throw-out <NUM> indexes into a pressure plate bearing <NUM> allowing the throw-out <NUM> to turn independently of the pressure plate <NUM>. The throw-out <NUM> is coupled to a throw-out rod <NUM>. The throw-out rod <NUM> is coupled to a clutch disengagement system (not shown). The clutch disengagement system (not shown) is operable to selectively position the throw-out rod <NUM> and throw-out <NUM> for the purpose of pushing the pressure plate <NUM> away from the clutch pack <NUM> to disengage the clutch. Alternatively, the clutch disengagement system (not shown) is operable to selectively position the throw-out rod <NUM> and throw-out <NUM> for the purpose of returning the pressure plate <NUM> into contact with the clutch pack <NUM> to engage the clutch. In another embodiment the clutch pack <NUM> is comprised of nine friction disks <NUM> and ten separator plates <NUM>. <FIG> and <FIG> disclose the clutch hub assembly <NUM> used within the multi-plate clutch <NUM> where the multi-plate clutch <NUM> is of typical construction similar to the prior art multi-plate clutches disclosed in <FIG> in order to demonstrate that the clutch hub assembly <NUM> could be used in place of the prior art clutch hub <NUM> disclosed in <FIG> and the prior art clutch hub <NUM> disclosed in <FIG>.

<FIG> depicts an exploded view of an alternative embodiment clutch hub assembly <NUM> including a clutch hub <NUM>, drive pin <NUM>, hold-down screw <NUM> and retention clip <NUM>. The clutch hub <NUM> includes a profiled ring <NUM>, semi-circular slots <NUM>, flange <NUM>, counter-bored holes <NUM>, threaded holes <NUM>, shelf <NUM>, spring-bolt post <NUM> and clip locating surface <NUM>. The semi-circular slots <NUM> terminate into the flange <NUM> resulting in counter-bored hole <NUM> being formed into the flange <NUM> of the clutch hub <NUM>. The semi-circular slots <NUM> and counter-bored hole <NUM> are of equal diameter and are of larger diameter than the outer diameter of the drive pins <NUM>. In another embodiment the semi-circular slots <NUM> and counter-bored holes <NUM> are of equal diameter and have a smaller diameter than the outer diameter of the drive pins <NUM> requiring a drive pin <NUM> to be pressed into a semi-circular slot <NUM> and counter-bored hole <NUM>. The drive pin <NUM> is cylindrical in shape and includes an inner bore <NUM>. The retention clip <NUM> has through-hole <NUM>, locating surface <NUM> and tab <NUM>.

<FIG> and <FIG> show the clutch hub assembly <NUM> with the drive pins <NUM> installed into the semi-circular slots <NUM> and counter-bored holes <NUM> of the clutch hub <NUM>. The hold-down screws <NUM> affix the retention clips <NUM> to the shelf <NUM> of the clutch hub <NUM>. The retention clips <NUM> are positioned such that the location surface <NUM> is indexed and rotationally locked against the clip locating surface <NUM> of spring-bolt post <NUM> of the clutch hub <NUM>. The tab <NUM> is received by the inner bore <NUM> of drive pin <NUM>. Also, shown in <FIG> and <FIG> the cutout <NUM> of the separator plate <NUM> is rotationally coupled to the drive pin <NUM>.

As best seen in <FIG>, one end of a drive pin <NUM> is placed into a counter-bored hole <NUM>. The opposite end of the drive pin <NUM> is secured via the tab <NUM> of the retention clip <NUM>. With the tab <NUM>, the retention clip <NUM> applies a compressive load against the top of the drive pin <NUM> securing the pin into the counter-bored hole <NUM> and thus constraining the drive pin <NUM> such that it is non-moveable in direction <NUM> and direction <NUM>, both parallel to center axis <NUM>. The tab <NUM> and counter-bored hole <NUM> secure the drive pin <NUM> such that the drive pin <NUM> is non moveable in a radial direction perpendicular to center axis <NUM>. In an alternative embodiment the retention clip <NUM> is formed such that the underside of the retention clip <NUM> completely covers the top surface of the drive pin <NUM> and includes a indexing boss extending into the inner bore <NUM> where the indexing boss secures the inner bore <NUM> such that the drive pin is non-moveable in a radial direction perpendicular to center axis <NUM>.

<FIG> depicts an exploded view of yet another alternative embodiment clutch hub assembly <NUM> which could be utilized in place of the clutch hub assembly <NUM>. The clutch hub assembly <NUM> includes a clutch hub <NUM>, drive member <NUM>, and screw <NUM>. The clutch hub <NUM> includes a profiled ring <NUM>, slots <NUM>, flange <NUM>, through holes <NUM>, radial holes <NUM>, and spring-bolt post <NUM>. The slots <NUM> have a rectangular profile having side walls <NUM> and back wall <NUM>. The slots <NUM> each receive a drive member <NUM>. The drive members <NUM> are comprised of a square shaped cross-section extending for a suitable length to accommodate various clutch pack heights. Each drive member <NUM> contains side walls <NUM> and a threaded hole <NUM>.

<FIG> and <FIG> show the clutch hub assembly <NUM> with the drive members <NUM> installed into the slots <NUM> of the clutch hub <NUM>. The screws <NUM> pass through the radial holes <NUM> and affix the drive members <NUM> to the clutch hub <NUM> via the threaded holes <NUM>. Also, shown in <FIG> and <FIG> the cutout <NUM> of the separator plate <NUM> indexes to a drive member <NUM> rotationally coupling the separator plate <NUM> to the clutch hub assembly <NUM>.

As best seen in <FIG>, one end of a drive member <NUM> is passes into the through hole <NUM>. The screws <NUM> and side walls <NUM> of the slots <NUM> secure the drive member <NUM> such that the drive members <NUM> are non-moveable in any direction relative to the clutch hub <NUM>. In an alternative embodiment the drive member <NUM> has a trapezoid cross-sectional shape. In yet another embodiment the drive member <NUM> has a rounded profile with a flat along its length for mating against a back wall <NUM>.

<FIG> depicts an exploded view of yet another alternative embodiment clutch hub assembly <NUM> which could be utilized in place of the clutch hub assembly <NUM>. The clutch hub assembly <NUM> includes a clutch hub <NUM> and u-shaped liner <NUM>. The u-shaped liner is comprised of vertical legs <NUM>, flaps <NUM> and horizontal base <NUM>. The flaps <NUM> are each connected to a vertical leg <NUM> of the u-shaped liner <NUM>. The vertical legs <NUM> are connected by a horizontal base <NUM>. The clutch hub <NUM> includes a profiled ring <NUM>, slots <NUM>, flange <NUM>, t-slots <NUM>, flange slots <NUM> and spring-bolt posts <NUM>. The slots <NUM> have a rectangular profile with side walls <NUM> and back wall <NUM>. The t-slots <NUM> extend downward from the top of the profile ring <NUM> toward the flange <NUM> running parallel to the side walls <NUM> of the slots <NUM>. Each t-slot <NUM> forms overhang walls <NUM> part way down and behind the side walls <NUM>. The purpose of the t-slot <NUM> is to accept the flaps <NUM> of the u-shaped liner <NUM>. The slots <NUM> with t-slots <NUM> together each receive a u-shaped liner <NUM>. When a u-shaped liner1530 is placed into a slot <NUM> the vertical legs <NUM> cover the side walls <NUM> of a slot <NUM>.

<FIG> and <FIG> show the clutch hub assembly <NUM> with the u-shaped liners <NUM> installed into the slots <NUM> of the clutch hub <NUM>. The flaps <NUM> are received by the t-slot <NUM>. The overhang walls <NUM> of each t-slot <NUM> prevent the u-shaped liner <NUM> from moving in a radial direction perpendicular to center axis <NUM>. Also shown in <FIG> and <FIG> the tooth <NUM> of the separator plate <NUM> indexes into the space between the vertical legs <NUM> of a u-shaped liner <NUM> rotationally coupling the separator plate <NUM> to the clutch hub assembly <NUM>.

As best seen in <FIG>, the horizontal base <NUM> of a u-shaped liner <NUM> passes into the flange slot <NUM>.

Claim 1:
An improved clutch hub assembly (<NUM>) for use in a clutch of the type having a clutch basket (<NUM>) with fingers and slots (<NUM>), at least one driven plate (<NUM>) and at least one driving plate (<NUM>), and a clutch hub (<NUM>), wherein said clutch basket (<NUM>) is rotationally coupled to said driving plate (<NUM>), wherein said clutch hub (<NUM>) is configured for selective rotational coupling to said driven plate (<NUM>) in response from pressure from a pressure plate (<NUM>), said improved clutch hub assembly characterized by
an improved clutch hub (<NUM>), wherein said improved clutch hub (<NUM>) comprising a profiled ring (<NUM>, <NUM>, <NUM>) and a feature (<NUM>) configured for mating engagement with a drive member (<NUM>);
a retaining mechanism (<NUM>) configured for connecting said drive member (<NUM>) to said feature (<NUM>), such that said drive member (<NUM>) is non-moveable relative to the improved clutch hub (<NUM>) body; and
wherein said drive member (<NUM>) is configured to engage said at least one driven plate (<NUM>) such that said driven plate (<NUM>) is rotationally coupled to said improved clutch hub (<NUM>).