V-spring configuration and end attachment assemblies therefor for use in a personal care appliance

Abstract

A V-spring member ( 18 ) for use in a driving system for a personal care appliance has regions ( 34, 36 ) at the ends of the spring which are large enough to support a contact with an end clamping assembly, the spring member including a cross-piece ( 40 ) extending between the longitudinal edges of the spring at the end regions, such that the ends of the spring member define a closed line. End clamping assemblies ( 16, 24 ) provided for such a V-spring member include a body portion ( 64 ) having a lower support portion ( 66 ) on which the V-spring is supported and a mating clamping member ( 88 ) positioned in registry with the support portion on top of the V-spring. The support portion and the clamping member include peripheral edges ( 74, 92 ) which have a curved cross-sectional configuration, and which are in registry, making contact with the spring member in the end regions in such a manner as to reduce stress concentrations in the end regions of the spring, thereby reducing fretting fatigue and fretting damage in the spring.

1 . A V-spring member for use in a driving system for a personal care appliance, comprising:
 an elongated solid spring member ( 18 ), having a cross-sectional configuration in the form of a V, wherein the spring member has regions ( 34 ,  36 ) at the ends thereof which are large enough to support a contact from an end clamping assembly, the spring member further including a cross-piece ( 40 ) extending between the longitudinal edges of the spring member in the end regions thereof, such that the ends of the spring member define a closed loop.   
     
     
         2 . The V-spring of  claim 1 , wherein the cross-piece is a unitary part of the spring member. 
     
     
         3 . The V-spring of  claim 1 , wherein the cross-piece is a separate piece fixedly secured between the longitudinal edges ( 37 ) of the spring member on the end regions thereof. 
     
     
         4 . The V-spring of  claim 1 , wherein the V angle is in the range of 45-170°. 
     
     
         5 . The V-spring of  claim 1 , wherein the V-angle is approximately 90°. 
     
     
         6 . The V-spring of  claim 1 , wherein the end regions extend a distance below the longitudinal edges of the V-spring at each end of the V-spring. 
     
     
         7 . The V-spring of  claim 1 , wherein the end regions are sufficiently stiff that the transition between the spring action and the end clamping assemblies at the ends thereof occurs within the spring. 
     
     
         8 . The V-spring of  claim 1 , wherein the ends of the V-spring are solid. 
     
     
         9 . The V-spring of  claim 1 , wherein the V-spring is made of steel. 
     
     
         10 . The V-spring of  claim 1 , including openings in the vicinity of the ends of the V-spring to permit a bolt to extend therethrough for clamping of the ends of the V-spring. 
     
     
         11 . The V-spring of  claim 1 , wherein the personal care appliance is a toothbrush. 
     
     
         12 . An end assembly for clamping an end of an elongated solid V-spring drive member used in a personal care appliance, comprising:
 an end block member ( 64 ) having a lower support portion ( 66 ) on which an end region of the V-spring is positioned, wherein the lower support portion includes an upper peripheral edge ( 74 ) which in cross-section is curved to contact an inner surface ( 67 ) of the V-spring in an end region thereof; and   a clamping member ( 81 ) which is positioned on top of the V- V-spring for clamping the end region of the V-spring to the lower support portion of the end block member, the clamping member having a lower surface configuration which fits over the V-spring, the clamping member including a peripheral edge ( 92 ), curved in cross-section, which contacts an outer surface of the V-spring substantially in registry with the lower support portion at the inner surface of the V-spring, wherein the physical contact between the lower support portion and the clamping member, respectively, and the V-spring, including the shape of the respective peripheral edges, results in reduced stress concentrations with the V-spring, thereby reducing fretting damage and fretting fatigue.   
     
     
         13 . The end assembly of  claim 12 , wherein the lower support portion includes a substantially vertical surface ( 70 ) which extends outwardly from the body portion, generally curving or angling to a center region  73 ) and then curving or angling back to the body portion, and wherein the clamping member has surfaces which are similar to or a mirror image of the lower support portion. 
     
     
         14 . The end assembly of  claim 12 , wherein the lower support portion has an upper surface ( 72 ) generally in the form of an inverted V with a V angle for support of the V-shaped spring, the lower support portion V angle being slightly less than the V-spring angle, and wherein the clamping member has a generally V-shaped lower surface ( 39 ) with a V angle slightly greater than the V-spring angle. 
     
     
         15 . The end assembly of  claim 12 , including a fastener assembly ( 81 ) for clamping the clamping member, the V-spring and the lower support portion firmly together. 
     
     
         16 . The end assembly of  claim 15 , wherein the fastener assembly is a bolt member which fits into threadable openings in the clamping member and the lower support portion. 
     
     
         17 . The end assembly of  claim 15 , wherein the fastener assembly is a bolt which extends through openings in the clamping member, the V-spring and the lower support portion for engagement with a nut member positioned below the lower support portion. 
     
     
         18 . The end assembly of  claim 12 , wherein the lower support portion is a unitary part of the end block member, and wherein the end block member, including the support portion, is comprised of a material which results in reduction of fretting of the V-spring. 
     
     
         19 . The end assembly system of  claim 12 , wherein the lower support portion material is selected from steel or zinc. 
     
     
         20 . The end assembly of  claim 12 , wherein the clamping member is aluminum. 
     
     
         21 . The end assembly of  claim 12 , wherein the personal care appliance is a toothbrush. 
     
     
         22 . An end assembly for clamping the ends of an elongated solid, closed end V-spring drive member used in a personal care appliance, comprising:
 an end block member ( 112 ,  114 ) having a triangular slot ( 116 ) in one surface thereof for receiving an end region of the V-spring, wherein the slot is sufficiently deep that when the V-spring is secured to the end assembly by an adhesive in the slot, efficient transfer of torque between the end block member and the V-spring occurs, and wherein the end block is further configured and arranged to minimize relative motion between the block member and the V-spring sufficiently to significantly reduce fretting damage to the spring and to significantly reduce contact stresses and stress concentrations in the end regions of the spring.   
     
     
         23 . An end assembly of  claim 22 , wherein the personal care appliance is a toothbrush. 
     
     
         24 . A spring member for use in a driving system for a personal care appliance, comprising:
 an elongated spring member ( 18 ) having regions ( 34 ,  36 ) at the ends thereof which are large enough to support a contact from an end clamping assembly and having a configuration such that stiffness transitions between the spring and the end clamping assembly occurs with the spring.   
     
     
         25 . The combination of a spring member and associated end assemblies for use in a driving system for a personal care appliance, comprising:
 an elongated solid spring member ( 18 ), having a cross-sectional configuration in the form of a V, wherein the spring member has regions ( 34 ,  36 ) at the ends thereof which are large enough to support a contact from an end clamping assembly, the spring member further including a cross-piece ( 40 ) extending between the longitudinal edges of the spring member in the end regions thereof; and   end block assemblies for clamping the ends of the spring member, comprising an end block member ( 64 ) having a lower support portion ( 66 ) on which the end region of the V-spring is positioned, wherein the lower support portion includes an upper peripheral edge ( 74 ) which in cross-section is curved to contact an inner surface ( 67 ) of the V-spring in an end region thereof, and clamping members ( 81 ) which are positioned on top of the V-spring for clamping the end region of the V-spring to the lower support portion of the end block member, the clamping member having a lower surface configuration which fits over the V-spring, the clamping member including a peripheral edge ( 91 ), curved in cross-section, which contacts an outer surface of the V-spring substantially in registry with the lower support portion at the inner surface of the V-spring, wherein the physical contact between the lower support portion and the clamping member, respectively, and the V-spring, including the shape of the respective peripheral edges, results in reduced stress concentrations with the V-spring, thereby reducing fretting damage and fretting fatigue.   
     
     
         26 . The combination of  claim 25 , wherein the end regions of the spring member are sufficiently stiff that the transition between the spring action and the end clamping assemblies at the ends thereof occurs within the spring. 
     
     
         27 . The combination of  claim 25 , wherein the personal care appliance is a toothbrush. 
     
     
         28 . The combination of  claim 25 , wherein the lower support portion of the end block member includes a substantially vertical surface ( 70 ) which extends outwardly from the body portion, generally curving or angling to a center region  73 ) and then curving or angling back to the body portion, and wherein the clamping member has surfaces which are similar to or a mirror image of the lower support portion. 
     
     
         29 . The combination of  claim 25 , including a fastener assembly ( 81 ) for clamping the clamping member, the V-spring and the lower support portion firmly together. 
     
     
         30 . The combination of a spring member and associated end assemblies for use in a driving system for a personal care appliance, comprising:
 an elongated solid spring member ( 100 ), having a cross-sectional configuration in the form of a V, wherein the member has regions at the ends thereof which are large enough to support a contact from an end clamping assembly; and   end clamping assemblies ( 102 ,  104 ) for clamping the ends of the spring member, each comprising an end block member having a lower support portion on which an end region of the V-spring is positioned, wherein the lower support portion includes an upper peripheral edge which in cross-section is curved to contact an inner surface of the V-spring in an end region thereof, and clamping members ( 105 ) which are positioned on top of the V-spring for clamping the end regions of the V-spring to the lower support portions of the end block members, the clamping members having a lower surface configuration which fits over the V-spring, the clamping members including a peripheral edge, curved in cross-section, which contacts an outer surface of the V-spring substantially in registry with the lower support portion at the inner surface of the V-spring, wherein the physical contact between the lower support portion and the clamping member, respectively, and the V-spring, including the shape of the respective peripheral edges, results in reduced stress concentrations with the V-spring, thereby reducing fretting damage and fretting fatigue.   
     
     
         31 . The combination of  claim 30 , wherein the end regions of the spring member are sufficiently stiff that the transition between the spring action and the end clamping assemblies at the ends thereof occurs within the spring. 
     
     
         32 . The combination of  claim 30 , wherein the personal care appliance is a toothbrush. 
     
     
         33 . The combination of  claim 30 , wherein the lower support portion of the end block member includes a substantially vertical surface ( 70 ) which extends outwardly from the body portion, generally curving or angling to a center region  73 ) and then curving or angling back to the body portion, and wherein the clamping member has surfaces which are similar to or a mirror image of the lower support portion. 
     
     
         34 . The combination of  claim 30 , including a fastener assembly ( 81 ) for clamping the clamping member, the V-spring and the lower support portion firmly together. 
     
     
         35 . The combination of a spring member and associated end assemblies for use in a driving system for a personal care appliance, comprising:
 an elongated solid spring member ( 10 ), having a cross-sectional configuration in the form of a V, wherein the spring member has regions at the ends thereof which are large enough to support a contact from end holding assemblies, the spring member further including a cross-piece extending between the longitudinal edges of the spring member and the end regions thereof; and   end assemblies ( 112 ,  114 ) for holding the ends of the V-spring, comprising an end block member having a triangular slot ( 116 ) in one surface thereof for receiving an end region of the V-spring, wherein the slot is sufficiently deep that when the V-spring is secured to the end assembly by an adhesive in the slot, efficient transfer of the torque between the end block member and the V-spring occurs, and wherein the end block is further configured and arranged to minimize relative motion between the block member and the V-spring sufficiently to significantly reduce fretting damage to the spring and to significantly reduce contact stresses and stress concentrations in the end regions of the spring.   
     
     
         36 . The combination of  claim 35 , wherein the end regions are sufficiently stiff that the transition between the spring action and the end clamping assemblies at the ends thereof occurs within the spring. 
     
     
         37 . The combination of  claim 35 , wherein the personal care appliance is a toothbrush. 
     
     
         38 . The combination of a spring member and associated end attachment assemblies for use in a driving system for a personal care appliance, comprising:
 an elongated solid spring member ( 120 ), having a cross-sectional configuration in the form of a V, wherein the spring member has regions at the ends thereof which are large enough to support a contact from an end holding assembly, the spring member further including a cross-piece between the longitudinal edges of the spring member and the end regions thereof, such that the ends of the spring member define a closed loop; and   end assemblies ( 122 ) for holding the ends of the V-spring, comprising an end block assembly configured to receive the end regions of the V-spring, wherein the V-spring is welded or brazed to the end block assembly so as to minimize relative motion between the end block member and the V-spring sufficiently to significantly reduce fretting damage to the spring and to significantly reduce contact stresses and stress concentrations in the end regions of the spring.   
     
     
         39 . The combination of  claim 38 , wherein the end regions of the spring member are sufficiently stiff that the transition between the spring action and the end clamping assemblies at the ends thereof occurs within the spring. 
     
     
         40 . The combination of  claim 38 , wherein the personal care appliance is a toothbrush.