Powered oscillating hand tool

Abstract

A powered oscillating hand tool includes a drive unit having an electric motor and a drive shaft; a bearing eccentrically mounted on the drive shaft and located radially eccentrically relative to the drive shaft; a carrier plate mounted on the bearing and a platen for mounting on the carrier plate. The carrier plate is provided with a first engagement means and the platen is provided with second engagement means to engage with the first engagement means by rotation of the platen relative to the carrier plate. The first and second engagement means together comprise a bayonet fitting.

1. A power oscillating hand tool comprising:
 a drive unit;  
 a carrier plate interconnected to the drive unit, the carrier plate including a plurality of first holes, each of the plurality of first holes partially defined by an inwardly projecting detent extending from one side thereof, the carrier further including a plurality of second holes, at least one of the second holes formed adjacent each of the first holes and providing an inward spring bias to the detents; and  
 a platen releasably secured on the carrier plate including a plurality of projections extending from an upper surface thereof, each projection extending through an associated first hole and cooperating with the associated first hole to maintain the platen on the carrier;  
 the detents each being biased into contact with an associated one of the projections.  
 
     
     
       2. The power oscillating hand tool of  claim 1 , wherein each of the projections includes a hook. 
     
     
       3. The power oscillating hand tool of  claim 2 , wherein the hook of each of the projections includes a flat face abutting a substantially vertical face of the associated first hole. 
     
     
       4. The power oscillating hand tool of  claim 1 , wherein each of the first holes is partially defined by a substantially horizontal platform abutting an underside of an associated one of the projections. 
     
     
       5. The power oscillating hand tool of  claim 1 , further comprising a central boss and wherein the first holes are radially spaced about the central boss. 
     
     
       6. The power oscillating hand tool of  claim 5 , wherein the plurality of first holes includes three first holes equally spaced radially about the central boss. 
     
     
       7. The power oscillating hand tool of  claim 1 , wherein the platen includes a first ramp surface and the carrier plate includes a second ramp surface, the first and second ramp surfaces cooperating to secure a tip portion of the platen to the carrier plate. 
     
     
       8. The power oscillating hand tool of  claim 1 , wherein each of the first holes extends completely through the carrier plate. 
     
     
       9. The power oscillating hand tool of  claim 1 , wherein the tool is a sander. 
     
     
       10. A power oscillating hand tool comprising:
 a drive unit;  
 a carrier plate interconnected to the drive unit, the carrier plate including a plurality of first holes, each of the first holes extending between a lower side of the carrier plate and an upper side of the carrier plate; and  
 a platen releasably secured on the carrier plate including a plurality of projections extending from an upper surface thereof, each projection corresponding to at least one of the first holes and including a portion abutting the upper side of the carrier plate.  
 
     
     
       11. The power oscillating hand tool of  claim 10 , wherein each of the projections includes a hook. 
     
     
       12. The power oscillating hand tool of  claim 11 , wherein the hook of each of the projections includes a flat face abutting a substantially vertical face of the associated first hole. 
     
     
       13. The power oscillating hand tool of  claim 10 , wherein each of the first holes is partially defined by a substantially horizontal platform abutting an underside of an associated one of the projections. 
     
     
       14. The power oscillating hand tool of  claim 10 , further comprising a central boss and wherein the first holes are radially spaced about the central boss. 
     
     
       15. The power oscillating hand tool of  claim 14 , wherein the plurality of first holes includes three first holes equally spaced radially about the central boss. 
     
     
       16. The power oscillating hand tool of  claim 10 , wherein the platen includes a first ramp surface and the carrier plate includes a second ramp surface, the first and second ramp surfaces cooperating to secure a tip portion of the platen to the carrier plate. 
     
     
       17. The power oscillating hand tool of  claim 10 , wherein the tool is a sander. 
     
     
       18. A power oscillating hand tool comprising:
 a drive unit;  
 a carrier plate interconnected to the drive unit, the carrier plate including a tip portion and a first ramp surface ;  
 a platen releasably secured on the carrier plate, the platen including a tip portion and a first ramp surface and the cover plate including a second ramp surface cooperating with the first ramp surface to secure the tip portion to the carrier plate.  
 
     
     
       19. The power oscillating hand tool of  claim 18 , wherein the first and second ramp surfaces angle upward in a rearward direction. 
     
     
       20. The power oscillating hand tool of  claim 18 , wherein the tool is a sander. 
     
     
       21. A power oscillating sander having an electric motor comprising:
   a housing defining an upper hand graspable handle and a forward curved surface, said housing having an upper periphery that generally extends from the front of the sander to the back of the sander and is substantially continuously convex; a manually operable switch to activate or deactivate the electric motor, said switch located on said forward curved surface of said handle and generally in front of the electric motor, whereby said switch is positioned to permit single - handed operation of said switch with one hand while said handle is being grasped by that same hand; and a platen defined by a rearward end terminating in two opposing corners from which sides extend and taper inwardly to form a forward tip; the forward curved surface of the housing extending from the front of the sander starting generally adjacent the platen.     
     
     
       22. The sander of  claim 21  wherein said handle is convex. 
     
     
       23. The sander of  claim 21  wherein said switch is located rearward of said platen tip and forward of said rearward end of said platen and said handle is palm graspable and allows the user to control the sander with the palm of a hand. 
     
     
       24. A power oscillating hand sander comprising:
   a housing defining a handle and an interior cavity, said handle generally extending from the front of the sander to the back of the sander and having a substantially continuously convex top surface; a platen defined by a rearward end terminating in two opposing corners from which sides extend and taper inwardly to form a forward tip; and a motor located in said cavity and over said platen, said motor having a drive shaft which is perpendicularly orientated with respect to said platen; the handle extending from the front of the sander starting generally adjacent the platen.     
     
     
       25. The sander of  claim 24  further comprising a switch which is located rearward of said platen tip and forward of said rearward end of said platen. 
     
     
       26. The sander of  claim 24  wherein said opposing corners of said platen are rounded. 
     
     
       27. A power oscillating hand sander comprising:
   a housing defining a convex shaped palm graspable handle, a forward curved surface located below and adjacent said handle, and an interior cavity, said handle generally extending from the front of the sander to the back of the sander having a substantially continuously convex top surface; a platen defined by a rearward end terminating in two opposing corners from which sides extend and taper inwardly to form a forward tip; a motor located in said cavity and over said platen, said motor having a drive shaft which is perpendicularly orientated with respect to said platen; and a manually operable switch to activate or deactivate the motor, said switch located on said forward curved surface and generally in front of said motor, whereby said switch is positioned to permit single - handed operation of said switch while said handle is being grasped in a palm of the single hand; the handle extending from the front of the sander starting generally adjacent the platen.     
     
     
       28. The sander of  claim 27  wherein said switch is located rearward of said platen tip and forward of said rearward end of said platen. 
     
     
       29. The sander of  claim 27  wherein said opposing corners of said platen are rounded. 
     
     
       30. A power oscillating hand sander having an electric motor comprising:
   a housing defining an upper hand graspable handle having a predetermined length and a forward curved surface located below and adjacent to said graspable handle, said handle generally extending from the front of the sander to the back of the sander and having a substantially continuously convex top surface; a platen having a predetermined length, said platen defined by a rearward end terminating in two opposing corners from which sides extend and taper inwardly to form a forward tip;        a manually operable switch to activate or deactivate the sander, said switch located on said forward curved surface above and rearward of said platen tip, forward of said rearward end of said platen and generally in front of the electric motor, whereby said switch is positioned to permit single - handed operation of said switch while said handle is being grasped by said single hand; and a majority of the length of said handle being located over the length of said platen; the handle extending from the front of the sander starting generally adjacent the platen.     
     
     
       31. A power oscillating hand sander having a motor comprising:
   a housing defining an interior cavity, a convex hand graspable handle having a predetermined length and a forward curved surface located generally in front of the motor, said handle generally extending from the front of the sander to the back of the sander and having a substantially continuously convex top surface; a platen having a predetermined length and defined by a rearward end terminating in two opposing corners from which sides extend and taper inwardly to form a tip; a vertically orientated motor located in said cavity above said platen, said motor having a drive shaft which is perpendicularly orientated with respect to said platen; a manually operable switch to activate or deactivate the toot, said switch located on said forward curved surface above and rearward of said platen tip and forward of said rearward end of said platen, whereby said switch is positioned to permit single - handed operation of said switch while said handle is being grasped by said single hand; and said handle rearwardly offset with respect to said platen tip with a majority of said handle length located over the length of said platen; the handle extending from the front of the sander starting generally adjacent the platen.     
     
     
       32. A power oscillating hand sander comprising:
   a housing defining an interior cavity, an upper convex hand graspable handle and a forward curved surface located below and adjacent to said graspable handle, said handle generally extending from the front of the sander to the back of the sander and having a substantially continuously convex top surface; a platen defined by a rearward end terminating in two opposing corners from which sides extend and taper inwardly to form a forward tip; a vertically orientated motor located in said cavity over said platen, said motor having a drive shaft which is perpendicularly orientated with respect to said platen; a manually operated switch to activate or deactivate the tool, said switch located on said forward curved surface above and rearward of said platen tip, forward of said rearward end of said platen and forward of said motor, whereby said switch is positioned to permit single - handed operation of said switch while said handle is being grasped by said single hand; and said handle rearwardly offset with respect to said platen tip with a majority of said handle located over said platen; the handle extending from the front of the sander starting generally adjacent the platen.     
     
     
       33. A power oscillating hand grasped sander comprising:
   a housing defining an interior cavity, an upper convex hand graspable handle and a forward curved surface located below and adjacent to said graspable handle, said housing generally extending from the front of the sander to the back of the sander and having a substantially continuously convex top surface; a platen defined by a rearward end terminating in two opposing corners from which sides extend and taper inwardly to form a forward tip; a vertically orientated motor located in said cavity over said platen, said motor having a drive shaft which is perpendicularly orientated with respect to said platen; a manually operable switch to activate or deactivate the sander, said switch located on said forward curved surface over and rearward of said platen tip and generally in front of said motor, whereby said switch is positioned to permit single - handed operation of said switch while said handle is being grasped by said single hand; and said handle rearwardly offset with respect to said platen tip with a majority of said handle located over said platen and with a minority of said handle displaced rearwardly of said platen; the housing extending from the front of the sander starting generally adjacent the platen.     
     
     
       34. A power sander comprising:
   a housing that generally extends from the front of the sander to the back of the sander and has a substantially continuously convex top surface; a platen disposed below said housing, said platen having a rear end defined by two opposing corners, said platen tapering inwardly forward from said rear end in a first direction to form a forward tip portion;        a motor disposed within said housing; and      
       
         said housing defining a graspable handle such that the majority of the graspable handle as measured along the first direction is disposed over said platen; the housing extending from the front of the sander starting generally adjacent the platen. 
       
     
     
       35. The sander recited in  claim 34 , wherein said first direction is a longitudinal direction of said platen. 
     
     
       36. The sander recited in  claim 35 , wherein at least a substantial portion of said graspable handle is defined above said motor. 
     
     
       37. The sander recited in  claim 35 , wherein at least two- thirds of said graspable handle is disposed over said platen.   
     
     
       38. The sander recited in  claim 35 , said sander further comprising a manually operable switch disposed on a forward surface of said housing. 
     
     
       39. The sander recited in  claim 38 , wherein said forward surface of said housing is curved. 
     
     
       40. A palm grip sander comprising:
   a housing;        a platen disposed below said housing, said platen having a rear end defined by two opposing corners, said platen tapering inwardly forward from said rear end in a longitudinal direction to form a forward tip Portion, said platen having a major working surface and oscillated about an oscillating axis which is substantially perpendicular to the major surface; a motor disposed within said housing; wherein said housing defines a top surface that generally extends from the front of the sander generally adjacent the platen to the back of the sander and that is substantially continuously convex and is the primary grasping surface of said sander such that said sander is gripped with a user's hand intersected by said oscillating axis.