Patent Publication Number: US-6669543-B2

Title: Interchangeable handle grip assembly, conversion kit, and tools incorporating same

Description:
BACKGROUND OF THE INVENTION 
     This invention relates generally to grips for powered tools and, more particularly, to an interchangeable handle grip assembly and a conversion kit for interchanging the palm grip of a pneumatic power tool to create an extended grip for enhanced control. 
     Currently, certain pneumatic operated tools having a grinding, buffing, polishing, or sanding wheel utilize a movable platen on which is secured a sheet of suitable material for the operation to be performed. The platen is below a main housing portion of the tool which contains a motor coupled to the platen for effecting movement thereof. A main handle portion is typically provided that, in the case of a pneumatic tool such as a palm sander, is configured for single-handed use by fitting the palm of a user. The smaller sizes of these palm-fitting tools are particularly advantageous for operations in confined or otherwise limited working spaces. Exemplary pneumatic tools in this regard are the Models IR 351, 354, 355 and 359 air-driven orbital sanders available from Ingersoll-Rand Company, Woodcliff Lake, N.J. 
     For operations requiring added gripping area, long-handled pneumatic tools are also available with an exemplary tool in this regard being the Model IR 352 long-handled grip air orbital sander also available from Ingersoll-Rand Company, Woodcliff Lake, N.J. The added gripping areas of these tools provide for added comfort by providing an alternate gripping surface that can be used alone using one hand or in combination with a main handle portion for two-handed operation, thereby providing added leverage and comfort, especially over extended operating periods. 
     Thus, in order to have the capability of optimally performing both single- and two-handed operations generally required a user to obtain both a palm-fitting tool and a tool with a long-handled grip, respectively. 
     The foregoing illustrates limitations known to exist in present devices and methods. Thus it is apparent that it would be advantageous to provide an alternative directed to overcoming one or more of the limitations set forth above. Accordingly, a suitable alternative is provided including features more fully disclosed hereinafter. 
     SUMMARY OF THE INVENTION 
     According to the present invention, an interchangeable handle grip assembly, conversion kit, and tools having an interchangeable handle grip are provided having an inlet extension tube and an outlet extension tube. The assembly includes a housing extension having a mounting bracket into which the inlet extension tube and the outlet extension tube are inserted. An extension grip cover fitted to cover at least a portion of the mounting bracket provides a gripping surface thereon. 
     The foregoing and other aspects of the invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawing figures. 
    
    
     BRIEF DESCRIPTION OF THE DRAWING FIGURES 
     FIG. 1 is a view of a conventional air orbital palm-sander; 
     FIG. 2 is a view of the conventional air orbital sander shown in FIG. 1; 
     FIG. 3 is an exploded side view of an interchangeable handle grip assembly showing the component parts in preassembly relationship with a conventional pneumatic sander; 
     FIG. 4 is a side view of the pneumatic sander of FIG. 3 assembled with an interchangeable handle grip assembly according to the present invention with an unattached vacuum adaptor; 
     FIG. 5 is a top view of the pneumatic sander of FIG. 3 assembled with an interchangeable handle grip assembly according to the present invention with an attached muffler; and 
     FIG. 6 is a rear view of the pneumatic sander of FIG. 5 assembled with an interchangeable handle grip assembly according to the present invention with an attached muffler. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The invention is best understood by reference to the accompanying drawings in which like reference numbers refer to like parts. It is emphasized that, according to common practice, the various dimensions of the component parts as shown in the drawings are not to scale and have been enlarged for clarity. 
     Referring now to the drawings, shown in FIGS. 1 and 2, a pneumatic power tool in the form of a conventional air orbital sander is generally designated by the reference numeral  1 . The sander comprises a motor housing portion  2 , a sanding disk  3 , and an operating lever  4 , which when depressed, causes the motor to run on compressed pneumatic fluid and work to be accomplished by the sanding disk  3 . Compressed pneumatic fluid is supplied at inlet  5  by a conventional pneumatic hose connection (not shown), the flow rate of which is controlled by an adjustable flow knob  6  having an actuator wing  16  to facilitate turning the knob. 
     Preferably when used as a pneumatic sander, a vacuum port  7  is provided for connecting to a central or portable vacuum system via a tubular vacuum adapter  50  shown in FIG. 4, to maintain a clean, dust-free environment. Vacuum adapter  50  has a tapered forward portion  56  that fits into vacuum port  7  and attaches to pneumatic sander  1  via a resilient latch  58  that engages an aperture  9  on pneumatic sander  1  as shown in FIG. 1. A rear attachment port  57  is configured to attach to a vacuum hose or system (not shown). An exemplary model of pneumatic sander  1  is the Model IR4151 vacuum-ready random orbital sander available from Ingersoll-Rand Company, Woodcliff Lake, N.J. which is shown and described in commonly assigned U.S. Pat. Nos. 5,581,842 and Des. 351,976, the disclosures of which are incorporated by reference herein. 
     As shown in FIGS. 1 and 2, pneumatic sander  1  is provided with an interchangeable grip ring  8  having an inner annular hole that engages a cylindrical mounting post  12  located on motor housing portion  2  via an interference fit. Grip ring  8  is preferably made of an elastomeric material and is sized to match the size of a user&#39;s hand for single-handed operation. 
     According to the present invention, an interchangeable handle grip assembly is provided having a housing extension  40 , an inlet extension tube  25 , an outlet extension tube  30 , an extension grip cover  60 , and an optional control knob  70  as shown in FIGS. 3-6. Turning to FIG. 3, shown is pneumatic sander  1  of FIG. 1 with grip ring  8  removed. 
     A housing extension  40  is provided having a mounting bracket  41  which, preferably is a longitudinally concave shell having a substantially elliptical cross-section, and an end plate  42  as shown in FIG.  6 . As described in detail below, when attached to pneumatic sander  1  via inlet extension tube  25  and outlet extension tube  30 , mounting bracket shell  41  acts as a support for extension grip cover  60 . Preferably provided on mounting bracket shell  41  is a vacuum port extension  45  having a tapered forward portion  46  that fits into vacuum port  7  and attaches to pneumatic sander  1  via a resilient latch  48  that engages aperture  9  on pneumatic sander  1  as shown in FIG.  4 . Vacuum port extension  45  is provided with a vacuum port  47  that fits tapered forward portion  56  of vacuum adapter  50  for attachment to a central or portable vacuum system or a port plug (not shown) when not in use. An aperture  49  is also provided to engage resilient latch  58  of vacuum adapter  50  when tapered forward portion  56  is inserted fully into vacuum port  7 . 
     Also shown in FIG. 3 are an inlet extension tube  25  and an outlet extension tube  30 . Inlet extension tube  25  has an externally threaded portion  26  on one end that mates with inner threads of inlet  5  and an inlet port connector  27  on the other end that is disposed next to a shoulder portion  28 . Inlet port connector  27  is preferably internally threaded for attachment to a compressed air source (not shown). Outlet extension tube  30  has an externally threaded portion  31  on one end that mates with inner threads of exhaust outlet  10  and an exhaust port connector  32  on the other end that is disposed next to a shoulder portion  33 . Exhaust port connector  32  is preferably internally threaded for attachment to a muffler  80  as shown in FIG.  5 . In addition to securing the housing extension  40  to pneumatic sander  1 , when attached to pneumatic sander  1 , inlet extension tube  25  and outlet extension tube  30  are in fluid communication with and extend inlet  5  and exhaust outlet  10 , respectively, to the end of the extension grip cover  60 . 
     Extension grip cover  60  is preferably made of a flexible, elastomeric material and has an outer surface shaped to have an ergonomically contoured design. As shown in FIGS. 4 and 5, extension grip cover  60  includes a grip ring portion  68  configured to fit over and engage cylindrical mounting post  12  and an extended handle portion  69  having an undersurface configured to stretch fit over and engage housing extension  40 . Preferably, a longitudinal lip along both sides of the undersurface of the grip cover are provided to achieve attachment to the housing extension  40 . Through holes and apertures (such as a hole  62  to accommodate an actuator for operating lever  4  and an aperture  61  to accommodate operating lever  4 ) and contours (such as shroud  71  for a control knob  70 ) can be provided to accommodate features to be located under or through the extension grip cover  60 . Although shown with an optional control knob  70  to be used in lieu of knob  6  for ease of operation, extension grip cover may alternatively be configured to accommodate knob  6  and its actuator wing  16 . 
     Conversion between a pneumatic sander having a palm configuration with grip ring  8  (as shown in FIGS. 1 and 2) to a pneumatic sander having an elongated grip configuration with extension grip cover  60  (as shown in FIGS. 4-6) may be accomplished as follows. Turning to FIG. 3, after removing grip ring  8  from cylindrical mounting post  12  and knob  6  (if it is to be changed out for control knob  70 ), housing extension  40  is aligned with pneumatic sander  1  as shown by the dotted lines in FIG.  3 . If present for use with a vacuum system, tapered portion  46  of vacuum port extension  45  is inserted into vacuum port  7  until resilient latch  48  engages aperture  9 . The threaded portions  26 ,  31  of inlet extension tube  25  and outlet extension tube  30 , respectively, are then inserted into holes located in end plate  42 , threaded into inlet  5  and exhaust outlet  10 , and tightened until shoulder portions  28 ,  33  compress against end plate  42  thereby capturing and securely fastening housing extension  40  to the body of pneumatic sander  1 . 
     After sliding operating lever  4  through aperture  62  and aligning any through-holes with any underlying features to protrude through extension grip cover  60 , grip ring portion  68  is then slid over cylindrical mounting post  12  and extended handle portion  69  is stretched around mounting bracket  41  to produce the pneumatic sander having an elongated grip configuration as shown in FIGS. 4,  5 , and  6 . Any remaining accessories, including vacuum adapter  50  and muffler  80 , are then inserted into their corresponding ports as described above. Reversion from a pneumatic sander having an elongated grip configuration with extension grip cover  60  back to a pneumatic sander having a palm configuration with grip ring  8  is accomplished by simply reversing the steps described above. 
     Thus, according to the present invention, an interchangeable handle grip assembly as described above is provided that permits the interchangeability between a pneumatic tool for single-handed use and a pneumatic tool having an extended handle with additional hand grip area. Among the advantages realized is the easy conversion between these tools using a minimum number of parts while also utilizing a single underlying tool body. Thus, the interchangeable handle grip assembly may be included with pneumatic tools such as a pneumatic sander to provide a two-in-one tool. Moreover, in addition to being able to be provided as original equipment with such tools, the interchangeable handle grip assembly may also be provided as a stand alone accessory or as a retrofit conversion kit. 
     While embodiments and applications of this invention have been shown and described, it will be apparent to those skilled in the art that many more modifications are possible without departing from the inventive concepts herein described. For example, although shown and described above with a mounting bracket  41  having a vacuum port extension  45  and tapered forward portion  46  that fits into a vacuum port  7 , it is envisioned that for pneumatic devices not having a vacuum port, housing extension  40  may be configured for attachment to a pneumatic tool using only mounting bracket  41  that is anchored via inlet extension tube  25  and outlet extension tube  30  as described in detail above. Additionally, although described above with respect to use with pneumatic orbital sanders, it is contemplated that the interchangeable handle grip assembly according to the present invention may be incorporated into other pneumatic devices in which the ability to change between shorter and longer grips is desired. 
     It is understood, therefore, that the invention is capable of modification and therefore is not to be limited to the precise details set forth. Rather, various modifications may be made in the details within the scope and range of equivalents of the claims without departing from the spirit of the invention.