Torsional vibration damper

Abstract

A vibration damper assembly operatively connecting a driving pulley with an automotive engine output shaft which drives a serpentine belt system with an automatic belt tensioner. The vibration damper assembly serves to dampen torsional, bending, and transitional vibrations transmitted from the output shaft through the poly-V belt and engine frame to the belt tensioner. The vibration damper assembly . .comprises.!. .Iadd.includes .Iaddend.a mounting element, fixed to the output shaft, in torsional transmitting relation therewith, bearing member operatively disposed between the driving pulley and the mounting element to restrict relative movement therebetween to torsional relative movement, and a resilient member operatively connected between the driving pulley and the mounting element in resilient torsional transmitting relation therebetween.

What is claimed is: . .1. The combination comprising: 
     
        therebetween..!.2. The combination as claimed in claim . .1.!. .Iadd.5 .Iaddend.wherein said resilient member comprises an input end and an output end, said input end being fixed to said mounting element and said output end being fixed to said driving pulley, said resilient member extending radially outward from said input end towards said output end. . .3. The combination as claimed in claim 1 further comprising a mass element annularly disposed about said output shaft for further damping 
     
     
        said bending and torsional vibrations of said output shaft..!.4. The combination as claimed in claim . .3.!. .Iadd.5 .Iaddend.further comprising an annular retaining element fixed to said mounting element for retaining said mass element in a radially spaced, concentric position 
     
     
        about said mounting element. 5. The combination . .as claimed in claim 3,.!. .Iadd.comprising: an internal combustion engine including an engine frame and an output shaft rotatable by operation of said internal combustion engine, said output shaft being subject to torsional and bending vibrations resulting from rotation thereof in conjunction with the operation of said internal combustion engine;   a plurality of driven shafts mounted for rotational movement about parallel axes fixed with respect to said engine frame;   a plurality of driven pulleys, each of said driven pulleys operatively connected with a corresponding one of said driven shafts;   a driving pulley for said output shaft;   an endless flexible poly-V belt trained about said driven and said driving pulleys, said poly-V belt being subject to transitional vibrations from changing rotational speeds of said output shaft;   a belt tensioner carried by the engine frame in tensioning engagement with said poly-V belt for maintaining said poly-V belt in driven engagement with said driving pulley and in driving engagement with said driven pulleys; and   a vibration damper assembly operatively connecting said driving pulley with said output shaft for damping said torsional vibrations, said bending vibrations, and said transitional vibrations transmitted from said output shaft through said poly-V belt and said engine frame to said belt tensioiner, said vibration damper assembly comprising   a mounting element, fixed to said output shaft, in torsional transmitting relation therewith;   bearing means operatively disposed between said driving pulley and said mounting element to restrict relative movement therebetween to torsional relative movement;   a resilient member operatively connected between said driving pulley and said mounting element in resilient torsional transmitting relation therebetween;   a mass element annularly disposed about said output shaft for damping said bending and torsional vibrations of said output shaft; and.Iaddend.   wherein said mass element is fixed to said mounting element through an   
     
     
        elastic damping element. 6. The combination as claimed in claim 4 wherein said mass element is connected to said annular retaining element via 
     
     
        . .an.!. .Iadd.said .Iaddend.elastic damping element. 7. The combination as claimed in claim . .1.!. .Iadd.5 .Iaddend.wherein said resilient member 
     
     
        is comprised of rubber. 8. The combination as claimed in claim 6 wherein 
     
     
        said elastic damping element is comprised of rubber. 9. The combination as claimed in claim . .1.!. .Iadd.5 .Iaddend.further comprising a back-up means for providing torsional transmission between said mounting element and said driving pulley in the event said resilient member fails in said 
     
     
        torsional transmission. 10. The combination as claimed in claim 7 . .wherein said.!. .Iadd.having .Iaddend.back-up means .Iadd.that .Iaddend.comprises: at least one protruding portion disposed on said mounting element and a corresponding edge surrounding a slot in said driving pulley, said protruding portion protruding through said slot in a spatially separated relation to said edge, said resilient member impeding relative rotational movement between said driving pulley and said mounting element so as to impede said protruding . .member.!. .Iadd.portion .Iaddend.from engaging said edge when said resilient member is in proper torsional transmitting relation between said mounting element and said driving pulley, said protruding . .member.!. .Iadd.portion .Iaddend.being able to engage said edge when said resilient member fails to be in said proper torsional transmitting relation so that said back-up means is in torsional transmitting relation between said mounting element and said driving   
     
     
        pulley. 11. The combination as claimed in claim . .1.!. .Iadd.5 .Iaddend.further comprising at least one accessory vibration damper assembly, each said accessory vibration damper assembly operatively connecting one of said driven pulleys with said corresponding one of said driven shafts, each said accessory vibration damper assembly damping torsional vibrations, bending vibrations, and transitional vibrations transmitted from said corresponding one of said driven shafts through said poly-V belt and said engine frame to said belt tensioner, each said accessory vibration damper assembly comprising   a driven mounting element; fixed to said corresponding one of said driven shaft, in torsional transmitting relation therewith;   driven bearing means operatively disposed between said one of said driven pulleys and said driven mounting element to restrict relative movement therebetween to torsional relative movement; and   a driven resilient member operatively connected between said one of said driving pulleys and said driven mounting element in resilient torsional   
     
     
        transmitting relation therebetween. 12. The combination comprising: an internal combustion engine including an engine frame and an output shaft rotatable by operation of said internal combustion engine, said output shaft being subject to torsional vibrations and bending vibrations resulting from rotation thereof in conjunction with the operation of said internal combustion engine;   a plurality of driven shafts mounted for rotational movement about parallel axes fixed with respect to said engine frame,   a plurality of driven pulleys, each of said driven pulleys operatively connected to a corresponding one of said driven shafts;   a driving pulley-for said output shaft;   an endless flexible poly-V belt trained about said driven and driving pulleys, said poly-V belt being subject to transitional vibrations from rotational speeds of said output shaft;   a belt tensioner carried by the engine frame, said belt tensioner comprising: (1) a fixed structure fixed with respect to said engine frame, (2) a movable structure mounted on said fixed structure for movement in one plane (3) a pulley element mounted on said movable structure for rotational movement about a rotational axis, and (4) biasing means for resiliently biasing said movable structure in a direction in said plane toward said poly-V belt for maintaining said pulley element in rotational tensioning engagement with said poly-V belt and for maintaining said poly-V belt in driven engagement with said driving pulley and in driving engagement with said driven pulleys, said movable structure being subject to oscillatory movement with respect to said fixed structure as a result of said torsional vibrations, said bending vibrations, and said transitional vibrations being transmitted to said movable structure from said output shaft through said poly-V belt and said engine frame; and   damping means for damping said oscillatory movement of said movable structure, said damping means comprising:   a mounting element, fixed to said output shaft, in torsional transmitting relation therewith;   bearing means operatively disposed between said driving pulley and said mounting element to restrict relative movement therebetween to torsional relative movement; and   a resilient member operatively connecting said driving pulley and said mounting element in resilient torsional transmitting relation   
     
     
        therebetween. 13. The combination as claimed in claim 12 wherein said resilient member comprises an input end and an output end, said input end being fixed to said mounting element and said output end being fixed to said driving pulley, said resilient member extending radially outward from 
     
     
        said input end towards said output end. 14. The combination as claimed in claim 12 . .further comprising.!. .Iadd.wherein .Iaddend.a mass element .Iadd.of the damping means is .Iaddend.annularly disposed about said output shaft for damping torsional and bending vibrations of said output 
     
     
        shaft. 15. The combination as claimed in claim 14 further comprising an annular retaining element fixed to said mounting element for retaining said mass element in a radially spaced; concentric position about said 
     
     
        mounting element. 16. The combination as claimed in claim 15 wherein said mass element is connected to said annular retaining element via an elastic 
     
     
        damping element .Iadd.of the damping means..Iaddend.17. The combination as claimed in claim 12 wherein said resilient member comprises a rubber 
     
     
        material. 18. The combination as claimed in claim 16 wherein said elastic 
     
     
        damping element comprises a rubber material. 19. The combination as claimed in claim 12 further comprising a back-up means for providing torsional transmission between said mounting element and said driving pulley in the event said resilient member fails in said torsional 
     
     
        transmission. 20. The combination as claimed in claim 19, wherein said backup means comprises: at least one protruding portion disposed on said mounting element and at least one corresponding edge surrounding a slot in said driving pulley, said protruding portion protruding through said slot in a spatially separated relation to said edge, said resilient member impeding relative rotational movement between said driving pulley and said mounting element so as to impede said protruding . .member.!. .Iadd.portion .Iaddend.from engaging said edge when said resilient member is in proper torsional transmitting relation between said mounting element and said driving pulley, said protruding . .member.!. .Iadd.portion .Iaddend.being able to engage said edge when said resilient member fails to be in said proper torsional transmitting relation so that said back-up means becomes in torsional transmitting relation between said mounting element and said   
     
     
        driving pulley. 21. The combination as claimed in claim 12 further comprising at least one accessory vibration damper assembly, each said accessory vibration damper assembly operatively connecting one of said driven pulleys with said corresponding one of said driven shafts, each said accessory vibration damper assembly damping torsional vibrations, bending vibrations, and transitional vibrations transmitted from said corresponding one of said driven shafts through said poly-V belt and said engine frame to said belt tensioner, each said accessory vibration damper assembly comprising   a driven mounting element, fixed to said corresponding one of said driven shaft, in torsional transmitting relation therewith;   driven bearing means operatively disposed between said one of said driven pulleys and said driven mounting element to restrict relative movement therebetween to torsional relative movement; and   a driven resilient member operatively connected between said one of said driving pulleys and said driven mounting element in resilient torsional   
     
     
        transmitting relation therebetween. .Iadd.22.  The combination according to claim 5, further comprising a mounting fastener constructed and arranged to fix said mounting element in mounted relation on said output shaft; said mounting fastener having a head portion constructed and arranged to be engaged and manipulated by a tool;   the combination being constructed and arranged so as to be devoid of any obstruction that would prevent movement of the tool in a direction parallel to an axis of said output shaft or along the axis of said output shaft and into engagement with the head portion of said mounting fastener..Iaddend..Iadd.23. The combination comprising:   an internal combustion engine including an engine frame and an output shaft rotatable by operation of said internal combustion engine, said output shaft being subject to torsional and bending vibrations resulting from rotation thereof in conjunction with the operation of said internal combustion engine;   a plurality of driven shafts mounted for rotational movement about parallel axes fixed with respect to said engine frame;   a plurality of driven pulleys, each of said driven pulleys operatively connected with a corresponding one of said driven shafts;   a driving pulley for said output shaft;   an endless flexible poly-V belt trained about said driven and said driving pulleys, said poly-V belt being subject to transitional vibrations from changing rotational speeds of said output shaft;   a belt tensioner carried by the engine frame in tensioning engagement with said poly-V belt for maintaining said poly-V belt in driven engagement with said driving pulley and in driving engagement with said driven pulleys; and   a vibration damper assembly operatively connecting said driving pulley with said output shaft for damping said torsional vibrations, said bending vibrations, and said transitional vibrations transmitted from said output shaft through said poly-V belt and said engine frame to said belt tensioiner, said vibration damper assembly comprising   a mounting element, fixed to said output shaft, in torsional transmitting relation therewith;   a mass element annularly disposed about an axis of said output shaft and fixed to said mounting element via an elastic damping element;   bearing means operatively disposed between said driving pulley and said mounting element to restrict relative movement therebetween to torsional relative movement;   a resilient member operatively connected between said driving pulley and said mounting element in resilient torsional transmitting relation therebetween; and   wherein an axial extent of said poly-V belt along the axis of said output shaft is axially overlapped with at least a portion of the mass element, at least a portion of the elastic damping element, and at least a portion   
     
     
        of the resilient member..Iaddend..Iadd.24.  The combination in claim 23, wherein an axial extent of said bearing means is axially overlapped with at least a portion of said mass element and at least a portion of said elastic damping element..Iaddend..Iadd.25. The combination in claim 23, wherein said axial extent of said bearing means is axially overlapped with at least a portion of said poly-V belt..Iaddend..Iadd.26. The combination as claimed in claim 23, further comprising a fastening structure constructed and arranged to mount said vibration damper assembly on said output shaft, wherein said mounting element has a fastener bearing surface constructed and arranged to receive force which is applied axially inwardly with respect to said output shaft when said fastening structure is tightened to mount the vibration damper assembly on said output shaft; said poly-V belt having at least a portion of its axial extent positioned further axially inwardly relative to the axial position of said fastener   
     
     
        bearing surface..Iaddend..Iadd.27.  The combination comprising: an internal combustion engine including an engine frame and an output shaft rotatable by operation of said internal combustion engine;   a plurality of driven shafts mounted for rotational movement about parallel axes fixed with respect to said engine frame;   a plurality of driven pulleys, each of said driven pulleys operatively connected with a corresponding one of said driven shafts;   a driving pulley for said output shaft;   an endless flexible poly-V belt trained about said driven and said driving pulleys;   a belt tensioner carried by the engine frame in tensioning engagement with said poly-V belt for maintaining said poly-V belt in driven engagement with said driving pulley and in driving engagement with said driven pulleys; and   a vibration damper assembly operatively connecting said driving pulley with said output shaft comprising:   a mounting element;   a mass element annularly disposed about an axis of said output shaft and fixed to said mounting element via an elastic damping element;   bearing means operatively disposed between said driving pulley and said mounting element to restrict relative movement therebetween to torsional relative movement; and   a resilient member operatively connected in radially extending relation relative to said axis of said output shaft between said driving pulley and said mounting element, said resilient member being disposed in radially resilient torsional transmitting relation between said mounting element and said driving pulley;   wherein said mounting element is constructed and arranged to mount said driving pulley, said mass element, said elastic damping element, said bearing means, and said resilient member as a unitary assembly on said output shaft; and   wherein an axial extent of said poly-V belt alone the axis of said output shaft is axially overlapped with at least a portion of the mass element, at least a portion of the elastic damping element, and at least a portion   
     
     
        of the resilient member..Iaddend..Iadd.28.  The combination in claim 27, wherein an axial extent of said bearing means is axially overlapped with at least a portion of said mass ring and at least a portion of said 
     
     
        elastic damping element..Iaddend..Iadd.29.  The combination in claim 27, wherein said axial extent of said bearing means is axially overlapped with at least a portion of said poly-V belt. .Iadd.30. The combination as claimed in claim 27, further comprising a fastening structure constructed and arranged to mount said vibration damper assembly and driving pulley on said output shaft, wherein said mounting element has a fastener bearing surface constructed and arranged to receive force which is applied axially inwardly with respect to said output shaft when said fastening structure is tightened to mount the vibration damper assembly on said output shaft; said poly-V belt having at least a portion of its axial extent positioned further axially inwardly relative to the axial position of said fastener bearing surface..Iaddend..Iadd.31. The combination as claimed in claim 27, wherein said resilient member comprises an input end and an output end, said input end being fixed to said mounting element and said output end being fixed to said driving pulley, said resilient member extending radially outward from said input end towards said output end..Iaddend..Iadd.32. The combination according to claim 27, wherein said elastic damping element is disposed in generally radially extending relation with respect to said axis of said output shaft and primarily dampens bending vibrations..Iaddend..Iadd.33. The combination according to claim 27, wherein said elastic damping element is disposed in generally axially extending relation with respect to said axis of said output shaft and primarily dampens torsional vibrations..Iaddend.