# US 8,464,853 B2 · Apparatus and system for automatic centrifugal engagement of a pressure plate > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,464,853 B2 - Document ID: US8464853B2 - Status: Granted - Kind: B2 - Application number: 12/141,780 - Filed: 2008-06-18 - Published: 2008-12-18 - Granted: 2013-06-18 - Earliest claimed: 2007-06-18 - Assignees: Rekluse Motorsports, Inc - Applicants: Albert J Youngwerth; Daniel S Youngwerth; Sean G Brown - Inventors: Albert J Youngwerth; Daniel S Youngwerth; Sean G Brown - Web page: https://patentgrep.com/patent/US8464853B2 ## CPC - F16D 43/10: the centrifugal masses acting directly on the pressure ring, no other actuating mechanism for the pressure ring being provided - F16D: COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES ## Abstract An apparatus and system are disclosed for automatic centrifugal engagement of a pressure plate. The apparatus includes a center clutch coupled rotationally with a transmission input shaft, a clutch basket coupled rotationally with an engine output shaft, and a clutch pack disposed between the center clutch and the clutch basked. The clutch pack includes a plurality of drive plates rotationally coupled to the center clutch and a plurality of friction plates rotationally coupled with the clutch basket. The apparatus also includes a pressure plate assembly that is spring-loaded and disposed between the center clutch and the clutch basket. The pressure plate assembly comprises a pressure plate, a spring plate, and a spring disposed between the pressure plate and the spring plate. The system includes the apparatus and a manual override capable of use with cable actuated and hydraulic actuated clutch levers. ## Claims ### Claim 1 An apparatus for automatic centrifugal engagement of a pressure plate, the apparatus comprising: a center clutch coupled rotationally with a transmission input shaft; a clutch basket coupled rotationally with an engine output shaft; a clutch pack disposed between the center clutch and the clutch basket, the clutch pack comprising a plurality of drive plates rotationally coupled to the center clutch and a plurality of friction plates rotationally coupled with the clutch basket; a centrifugal pressure plate assembly that is spring-loaded and disposed between the center clutch and the clutch basket, the centrifugal pressure plate assembly comprising a pressure plate, a spring plate, and a spring disposed between the pressure plate and the spring plate; a rotating standoff hub passing through and rotationally coupled with the center clutch and an engagement spring configured to apply a spring force to said centrifugal pressure plate assembly through the rotating standoff hub to prevent engagement of the clutch pack until the centrifugal pressure plate assembly has reached a predetermined speed. ### Claim 2 (depends on 1) The apparatus of claim 1, wherein the spring plate is further configured with a snap ring groove configured to engage a snap ring. ### Claim 3 (depends on 2) The apparatus of claim 2, wherein the snap ring is configured to limit the axial movement of the pressure plate relative to the spring plate and preload the spring. ### Claim 4 (depends on 2) The apparatus of claim 2, wherein the spring comprises a wave spring preloaded with a force in the range of between about 100 and 600 pounds. ### Claim 5 (depends on 1) The apparatus of claim 1, wherein the pressure plate comprises a plurality of ramps positioned radially around the perimeter of the pressure plate, each ramp configured to maintain one centrifugal actuating member. ### Claim 6 (depends on 5) The apparatus of claim 5, wherein the centrifugal actuating member is selected from a group consisting of ball bearings, needle bearings, roller bearings, and tapered roller bearings. ### Claim 7 (depends on 5) The apparatus of claim 5, wherein the ramps comprise a first incline portion and a second incline portion, the first incline portion having an angle greater than the second incline portion and extending for a length sufficient to allow the centrifugal actuating member to cause at least partial clutch engagement while on the first incline portion. ### Claim 8 (depends on 1) The apparatus of claim 1, further comprising a cable manual override configured to enable manual override of clutch engagement, the cable manual override comprising a cable actuated clutch lever coupled with a throw-out assembly, the throw-out assembly configured to axially move a top plate and disengage the clutch. ### Claim 9 (depends on 8) The apparatus of claim 8, wherein the engagement spring is disposed between the rotating standoff hub and the throw-out and configured to provide a force that maintains the cable actuated clutch lever in a disengaged position. ### Claim 10 (depends on 1) The apparatus of claim 1, further comprising a hydraulic manual override configured to enable manual override of clutch engagement, the hydraulic manual override comprising a hydraulic actuated clutch lever coupled with a throw-out assembly, the throw-out assembly configured to axially move a top plate and disengage the clutch. ### Claim 11 A system for automatic centrifugal engagement of a pressure plate, the apparatus comprising: a center clutch coupled rotationally with a transmission input shaft; a clutch basket including an opening and a base opposite the opening and coupled rotationally with an engine output shaft; a clutch pack disposed between the center clutch and the clutch basket, the clutch pack comprising a plurality of drive plates rotationally coupled to the center clutch and a plurality of friction plates rotationally coupled with the clutch basket; a centrifugal pressure plate assembly that is spring-loaded and disposed within the opening of the clutch basket and in contact with the base of the clutch basket, the centrifugal pressure plate assembly comprising a pressure plate, a spring plate, and a spring disposed between the pressure plate and the spring plate; wherein the spring plate is further configured with a snap ring groove configured to engage a snap ring and including a rotating standoff hub passing through and rotationally coupled with the center clutch and an engagement spring configured to apply a spring force to said centrifugal pressure plate assembly through the rotating standoff hub to prevent engagement of the clutch pack until the centrifugal pressure plate assembly has reached a predetermined speed. ### Claim 12 (depends on 11) The system of claim 11, wherein the snap ring is configured to limit the axial movement of the pressure plate relative to the spring plate and preload the spring. ### Claim 13 (depends on 11) The system of claim 11, wherein the spring comprises a wave spring preloaded with a force in the range of between about 100 and 600 pounds. ### Claim 14 (depends on 11) The system of claim 11, wherein the pressure plate comprises a plurality of ramps positioned radially around the perimeter of the pressure plate, each ramp configured to maintain one centrifugal actuating member. ### Claim 15 (depends on 11) The system of claim 11, further comprising a wave spring disposed between the rotating standoff hub and a throw-out and configured to provide a force that maintains the actuated clutch lever in a disengaged position.