Title of Invention

"PIVOT POINT RELEASE LOAD ADJUSTER FOR USE IN PULL TYPE ANGLE SPRING CLUTCH"

Abstract

A pivot point release load adjuster in a pull type angle spring clutch having a pair of pins connected to the housing end, a cradle swivelingly disposed on the pins, a pressure spring seat swivelingly disposed on release sleeve retainer pins and a pressure spring located between the cradle on the housing end and the pressure spring seat on the release sleeve retainer end has been disclosed. The cradle is operatively positioned on the pins thereby enabling the cradle to swivel about a pivot axis at a distance, between the pressure spring seat and the pivot axis. The adjuster is adapted to operatively adjust the pivot axis away from the seat of the pressure spring towards the sleeve retainer end of the pressure spring whereby a desired lever ratio is achieved.

Full Text

Field of Invention The present invention relates to pivot point release load adjuster for use in a pull type angle spring clutch. Background of the Invention Clutches are well known mechanisms used in automobiles, which are devices adapted to typically connect a driven means and a rotational power source. The rotational power source is usually the crankshaft of an automobile engine. A clutch device is having an engaged position and a disengaged position. Typically, a plurality of springs is used to move the clutch pedal from an engaged position to a disengaged position. The plurality of springs requires a high magnitude of force to be exerted on the clutch pedal for arriving at the disengaged position. Consequently the operator of an automobile vehicle is required to exert a high amount of pressure on the clutch pedal frequently at the time of changing gears resulting in discomfort and fatigue after continuous driving for long durations. There are many examples of prior art pedal pressure minimizing clutch devices, but most of them involve complex and expensive mechanisms. These are prone to wear and tear thus subject to premature failure. Efforts to minimize the release load on the clutch pedal while maintaining a higher clamp load with a view to arrive at a better driving comfort have been going on and this objective has been well recognized and pursued continuously over the years. The principle of using thrust springs at an angle to provide clamp load in clutches has been made applicable in many of the prior art pull type clutch devices. In pull type clutches employing thrust springs, a load is applied to the end of a lever so that in the release position the spring load is contained between the levers and the cover. The geometry changes as the clutch is released giving a change in the axial effort. Since the springs are located at each end, the constraints on the geometry together with the spring rate determines what changes in the angular load can be achieved. Applying this principle, spring loaded pull type clutch devices have been used to arrive at desired rates in the angular loads. However there are limitations in the known devices, necessitating further efforts to minimize the pedal pressure to a more comfortable level. Prior Art References In the past, it has been well known to construct a clutch pressure plate assembly, employing angle springs. Identical arrangements providing mechanical constructions directed to using thrust springs at an angle to provide clamp load in clutches can be found in the following US Patents. US Patent No. 4, 034, 836 to Sink et. al. titled "Clutch with Friction reducing Lever Assembly" discloses a clutch with an improved connection for release levers including an opening in the lever provided with a longitudinally extending sharp knife-edge for cooperating with a longitudinally extending pivot axis formed on an integral support means associated with one of the elements of the clutch. The integral support means and lever openings are constructed in such a manner as to positively constrain the levers in both a radial and circumferential direction with respect to the clutch element associated with. By this arrangement, the levers are positively retained with respect to the clutch element so that no relative movement occurs between the levers and the mating clutch element. The invention provides for an integral support means on one of the clutch elements which cooperates with an opening in the clutch levers to positively prevent any relative movement therebetween. US Patent No. 4, 760, 906 to Flotow et. al. titled "Internal Assisted Clutch" discloses a clutch cover assembly including a clutch cover and pressure plate axially moveable relative thereto and unitarily rotatable therewith. The invention brings an improvement in spring loaded clutches wherein an assisting force internally of the clutch cover assembly is generated when the clutch release mechanism is activated. More particularly, in a preferred embodiment, three springs are disposed circumferentially equidistant about the clutch release collar. The release collar is provided with radially outwardly extending ramped surfaces against which the radially inner end of the assister springs engage and react. The radially outer ends of the assister springs are received on similar radially inwardly extending ramped surfaces formed in the clutch cover. When the clutch is in the engaged position the compressed assister springs are each disposed with its axis positioned radially with respect to the axis of the release collar and therefore do not urge the release collar axially, but rather their forces are directed radially only. However when the release collar is moved axially relative to the clutch cover, such as would occur when the clutch is being disengaged, the assistor springs are tilted away from their radial position, such that a component of their force urges the collar in the direction of its movement, assisting the collar in overcoming the load of the clutch engaging springs. US Patent No. 4, 936,432 to Flotow et. al. titled "Internal Assisted Clutch Components and Assembly" discloses a clutch cover assembly having a cover, a plurality of engagement spring seats and a plurality of assister spring seats on the cover. The engagement and assister spring seats are all formed integrally with the cover and includes portions having generally V-shaped cross sections. The assembly further includes a release sleeve which is also formed as a one piece casting. A plurality of engagement spring seats and a plurality of assister spring seats are also provided on the release sleeve. The engagement and assister spring seats are all formed integrally with the release sleeve and includes portions having generally V-shaped cross sections. The engagement spring seats on the cover and the release sleeve are provided to pivotably pilot engagement springs for the clutch, while the assister spring seats on the cover and the release sleeve are provided to pivotably pilot assister springs. The engagement springs each have a generally oval shape throughout most of the length thereof. US Patent No. 5, 373, 927 to Gochenour et al. titled "Clutch release assembly" discloses a clutch engaging assembly having a sleeve member positioned circumferentially about a drive shaft, wherein the sleeve member includes a radially outwardly extending circumferential flange. A spring collector is positioned circumferentially about the sleeve member by a plurality of radially extending and angled coil springs positioned between the spring collector and the clutch cover. The angled springs, along with a plurality of axially extending spring members, urge the spring collector towards the flange of the sleeve member. A clearance is maintained between the sleeve member and the spring collector. The spring collector is not fixed to any member of the clutch, and is permitted limited radial movement about the sleeve member US Patent No. 5, 067, 602 to Flotow et al. titled "Internally Assisted Clutch" discloses an internally assisted friction clutch having both engagement springs and assister springs extending between a cover and a release sleeve. The radially directed forces exerted by the springs continually center and rotatably drive the release sleeve co-axially relative to the cover under normal operating conditions. In order to prevent excessive relative rotation, a plurality of protrusions are formed on the release sleeve which extend into respective recesses formed on the cover. The recesses are sized to be significantly larger than the protrusions so as to cause engagement only when four to five degrees of relative rotational movement or more occurs between the release sleeve and the cover. Summary of the Invention The present invention relates to pivot point release load adjuster for use in a pull type angle spring clutch wherein a novel adjuster has been brought out to give greater flexibility in varying the axial load and in turn the release load to any desired configuration. A pin means and a cradle means have been devised so as to enable a swiveling movement of the cradle means on which the housing end of the pressure springs are mounted. The pin means is connected to the housing of the clutch and the swiveling end of the pin means is having a pivoted contact surface on the cradle on which the springs are swivelingly mounted. This swiveling mechanism helps in obtaining the desired pivot point at a desired distance away from the spring seat on the swiveling end. The possibility of achieving the pivot point at such desired point away from the spring seat results in an increase in the lever ratio, consequently the release load is decreased and the pedal pressure is lowered. The goal of the present invention is therefore to bring down the pedal pressure to the desired minimum level thereby achieving better driving comfort. Pressure springs are mounted on the pressure spring seat means on the sleeve retainer end. Pressure spring seat means have been provided on the release sleeve retainer with push pin means to help the pressure spring move in either direction. Release sleeve retainer pin means are connected to the release sleeve retainer. The cradle has been provided on the housing end to help move the pressure springs as and when activations are made to disengage the clutch. Pressure spring seat means and release lever retainer pin means arc used to keep the pressure springs axially in location as and when wear takes place on the pressure plate or any of the related parts thereof. A push type adjusting has been used to adjust the setting height of clutches in the vehicles in the assembled condition. A replaceable brake disc has been provided to brake the clutch RPM. Statement of the Invention A pivot point release load adjuster in a pull type angle spring clutch characterized in that comprising a cradle with a spring seat and having receiving ends defining a pivot axis wherein the spring seat is positioned at a distance from the pivot axis so as to define a desired lever ratio therebetween, a pair of pins connected at one end to a housing and another end pivotally connected to the receiving ends of the cradle, the pivotal end of the pins being adapted to provide pivotal motion to the cradle when pressure is applied. Further the pivot point release load adjuster also includes one or more pressure springs disposed on the spring seat of the cradle so as to apply pressure thereto wherein the cradle is operatively positioned on the pivotal end of the pins enabling the cradle to swivel about the pivotal end of the pins and wherein a distance between the pivotal end and the support plate of the cradle is so adjusted as to provide a desired lever ratio. Brief Description of the Drawings In order to have a fuller and more complete understanding of the nature and goal of the present invention, reference must be made to the following detailed description made in conjunction with the accompanying drawings, in which: Fig. 1 shows the configuration of the top view of the pivot point release load adjuster. Fig. 1 A shows the configuration of the side view of the pivot point release load adjuster. Fig. 2 shows the pivot point release load adjuster with spring mounted on cradle on the housing end and on the pressure spring seat means on the release sleeve retainer end. Fig. 3 is the sectional view of the improved embodiment of the pull type angle spring clutch wherein the pivot point release load adjuster is placed. Detailed Description of a Preferred Embodiment The present invention discloses a pivot point release load adjuster which gives greater flexibility in varying the axial load and in turn the release load to any desired configuration. The pivot point release load adjuster comprises a cradle having a spring seat and receiving ends defining a pivot axis, a pair of pins and a plurality of pressure springs. The spring seat is positioned at a distance from the pivot axis so as to define a desired lever ratio, the pair of pins connected at one end to a housing and the other end pivotally connected to the receiving ends of the cradle, and the pivotal ends of the pins are adapted to provide pivotal motion to the cradle on applying pressure, the plurality of springs disposed on the spring seat of the cradle for applying pressure. The cradle is operatively positioned on the pivotal ends of the pins and enables the cradle to swivel about the pivotal end of the pins. This swiveling mechanism helps in obtaining the desired pivot point at a desired distance away from the spring seat on the swiveling end. The possibility of achieving the pivot point at such desired point away from the spring seat results in an increase in the lever ratio, consequently the release load is decreased and the pedal pressure is lowered. The distance from the pivot axis defined by the receiving ends is adjustable by various configurations of the cradle to provide a desired leverage ratio between the spring seats(s) and the pivot axis defining the receiving ends. The cradle also provides pivotal motion about the receiving ends to allow the coil springs to compress and extend along the spring axis while minimizing side loading and thus desirable canting of the coil springs and thereby bringing down the pedal pressure to the desired minimum level and consequently achieving better driving comfort. The pivot point release load adjuster disclosed is used in a pull type angle spring clutch. Referring now to the drawings, there is illustrated in Fig. 1, Fig. 1 A, and Fig. 2 a pivot point adjuster. Fig. 1 is the top view of the pivot point adjuster whereas Fig. 1A is the side view. Fig. 3 shows the housing 1 formed of a single piece of gray cast iron. The main body of the housing 1 is generally annular in shape and is adapted to comprise the pivot point adjuster. The pivot point adjuster is having the pin means 6 and is made of steel, which is hardened and tempered. All pin means (six in number) are connected to the housing 1. Pressure springs are located on the cradle 3 and it swivels about the hardened and tempered pin means 6, the bottom portion of the springs is seated on the cradle 3. Pressure spring seat means 4 are located on release sleeve retainer pin means 2. Pressure spring seat means are pressed from low carbon sheet material. The release sleeve retainer pin means 2 are made of steel and are hardened and tempered and connected to release sleeve retainer 5. An annular pressure plate is connected with the housing 1 by means of equi-spaced lug and slots arrangements. The lug and slots arrangements are conventional in the art and are provided to easily enter these parts in the housing to rotate and to drive the pressure plate thereby allowing the pressure plate to move axially relative to the housing. The pressure plate is hooked with the housing, the pressure plate being pulled by return springs fitted on the periphery of the housing. The pressure plate friction face is fine machined to have better grip and to reduce the wear of the clutch lining fitted on the disc friction material. The pressure plate is fitted to transmit the torque with the help of the clutch disc, which is having an adjusting ring having outer threads to fit on the inner threads formed on the housing. Rotation of the adjusting ring relative to the housing causes axial movement of the adjusting ring. The adjusting ring is rotated manually by adjusting gear assembly to reset the height. The levers are fitted on the adjusting ring to pressurize the pressure plate and are connected with release sleeve retainer groove to move the release sleeve, which is further locked with release sleeve half rings and snap ring on the end of the release sleeve and is fitted with deep groove ball bearing and locked with an external snap ring. Deep groove ball bearing is further locked by two release bearing spring to avoid loosening of the bearing during performance. Self-lubricating bush is provided inside the release sleeve to guide the clutch drive shaft. Two grease nipples are provided to fill high temperature grease and to provide nearest location to grease in the rotating complete assembly as fitted on the vehicle, between the bearing cage and deep groove ball bearing. A bearing cage cover to avoid entering of dust on the deep groove ball bearing is provided on the bearing cage assembly. Two bearing cage pads are employed for avoiding digging on the bearing cage during lifting the bearing cage by fork during disengagement of the clutch. In accordance with the provisions of patent statutes, the substantive principle and the mode of operation of the present invention have been described and illustrated in the preferred embodiment. However it must be construed that the present invention may be carried out and worked otherwise than as specifically described and illustrated with the support of drawings without deviating from its spirit and scope. We Claim: 1. A pivot point release load adjuster in a pull type angle spring clutch characterized in that comprising: a cradle comprising a spring seat and having receiving ends defining a pivot axis wherein the spring seat is positioned a distance from the pivot axis so as to define a desired lever ratio therebetween; a pair of pins connected at one end to a housing and another end pivotally connected to the receiving ends of the cradle, the pivotal end of the pins being adapted to provide pivotal motion to the cradle when pressure is applied; and one or more pressure springs disposed on the spring seat of the cradle so as to apply pressure thereto wherein the cradle is operatively positioned on the pivotal end of the pins enabling the cradle to swivel about the pivotal end of the pins and wherein a distance between the pivotal end and the support plate of the cradle is so adjusted as to provide a desired lever ratio. 2. The pivot point release load adjuster as claimed in claim 1, wherein the cradle comprises at least one spring seat arranged for placing the pressure springs. 3. The pivot point release load adjuster as claimed in claim 1, wherein the pivotal end of the pins defines a tapered profile. 4. The pivot point release load adjuster as claimed in claim 1, wherein the receiving ends of the cradle are correspondingly contoured to the profile of the pivotal end of the pins. 5. The pivot point release load adjuster as claimed in claim 1, wherein the cradle is adapted to provide a seating location for the springs towards the housing end. 6. The pivot point release load adjuster as claimed in claim 1, wherein the pins are made of steel and are heat treated. 7. The pivot point release load adjuster as claimed in claim 1, wherein the pressure springs are seated on pressure spring seats swivelingly engaged with corresponding release sleeve retainer pins so as to define pivot points so as to enable the springs to swivel about the respective pivot points. 8. The pivot point release load adjuster as claimed in claim 1, wherein the cradle comprises heat-dissipating openings arranged at a housing end thereof. 9. The pivot point release load adjuster for use in pull type angle spring clutch as herein described according to any of the preceding claims and supported by the description and the drawings.

Documents:

192-del-2001-abstract.pdf

192-del-2001-claims.pdf

192-del-2001-correspondence-others.pdf

192-del-2001-correspondence-po.pdf

192-del-2001-description (complete).pdf

192-del-2001-drawings.pdf

192-del-2001-form-1.pdf

192-del-2001-form-13.pdf

192-del-2001-form-19.pdf

192-del-2001-form-2.pdf

192-del-2001-form-26.pdf

192-del-2001-form-3.pdf

192-del-2001-form-5.pdf

192-del-2001-petition-138.pdf