Abstract:
Embodiments of the present invention are directed to a dust collection attachment system for use with a power tool having an elongated housing with a nose portion with a rotary output shaft, the nose portion being configured to have an accessory device mounted thereon, the system comprising a flexible dust hose attachable to the accessory device for removing dust and particles from the immediate area of the accessory device, the accessory device having a dust exhaust port for connection with the hose and a hose support removably attached to a rear end portion of the power tool opposite the nose portion thereof for supporting the dust hose, the support having a releasable mounting clasp on one end for attachment to the rear end of the power tool and a hose retaining clip attached to the mounting clasp

Description:
BACKGROUND OF THE INVENTION 
       [0001]    The present invention generally relates to small handheld power tools, and more particularly to a dust collection attachment system for such tools. 
         [0002]    Small handheld power tools that perform drilling, sawing and other types of cutting and the like are known in the prior art and have been widely used by hobbyists, artisans, tradesmen and others in a wide variety of applications. Such rotary hand tools generally have a motor with a rotary output shaft that extends from a nose portion that is more recently configured to connect to various accessories or attachment devices. Some of these rotary hand tools are quite powerful for their size and are used by tradesmen in the building trades as spiral saws that use a side cutting rotary bit to penetrate and rapidly cut holes in drywall paneling for electrical switches, outlets, light fixtures and the like. 
         [0003]    As is known in the art, such rotary hand tool tasks can be more easily performed by using an accessory device that is attached to the tool. For example, a depth adjustment accessory device is often used with such a cutting tool to limit the penetration of a cutting bit, particularly a spiral bit which is used to cut openings and the like in a drywall sheet. Other types of accessory devices may be used to facilitate increased control for delicate and/or accurate detail cutting. 
         [0004]    There is an increased awareness of health considerations in the use of hand tools which create dust and other airborne particles that may be adjusted by a user during operation of such tools. Also, the general desire to limit the dispersion of dust and particles in an area where such a tool is being used is highly desirable. It is for these reasons that many of the accessory devices that have been designed and marketed have a capability of collecting dust in association with some type of vacuum source that may be available to the user of such tools. 
       SUMMARY OF THE INVENTION 
       [0005]    Embodiments of the present invention are directed to a dust collection attachment system for use with a power tool having an elongated housing with a nose portion with a rotary output shaft, the nose portion being configured to have an accessory device mounted thereon, the system comprising a flexible dust hose attachable to the accessory device for removing dust and particles from the immediate area of the accessory device, the accessory device having a dust exhaust port for connection with the hose and a hose support removably attached to a rear end portion of the power tool opposite the nose portion thereof for supporting the dust hose, the support having a releasable mounting clasp on one end for attachment to the rear end of the power tool and a hose retaining clip attached to the mounting clasp 
         [0006]    Other embodiments comprise a compact adapter for interconnecting the dust hose and a selected one of multiple diameter hoses for connection to a vacuum source. 
     
    
     
       DESCRIPTION OF THE DRAWINGS 
         [0007]      FIG. 1  is a left plan view of a handheld rotary power tool having an elongated housing with a bottom nose portion to which a depth guide accessory device is attached and also illustrating portions of the dust collection attachment system embodying the present invention, particularly showing a dust hose attached to the depth guide and a clip at the rear upper end of the hand tool for supporting the depth hose; 
           [0008]      FIG. 2  is an isomeric view illustrating the hose clip shown in  FIG. 1 ; 
           [0009]      FIG. 3  is a top view of the hose clip shown in  FIG. 2 ; 
           [0010]      FIG. 4  is a cross-section taken generally along the line  4 - 4  of  FIG. 3 ; 
           [0011]      FIG. 5  is an isomeric view of an adaptor for interconnecting said dust hose and a selected one of multiple sized larger hoses that extend to a vacuum source; 
           [0012]      FIG. 6  is a right end view of the adaptor shown in  FIG. 5 ; 
           [0013]      FIG. 7  is a cross-section taken generally along the line  7 - 7  of  FIG. 6 ; and 
           [0014]      FIG. 8  is an enlarged plan view of a portion of the dust hose shown in  FIG. 1 . 
       
    
    
     DETAILED DESCRIPTION 
       [0015]    The present invention is directed to a dust collection attachment system for use with a relatively small handheld power tool of the type which has an elongated housing that is sized to be easily held with a single hand by a user. The housing has a nose portion with an output shaft that is accessible through an opening. The nose portion is designed and configured to receive various types of accessory devices that can be mounted on the nose portion. While it is noted that such power tools generally have a rotary output shaft, it should be understood that the dust collection attachment system embodying the present invention could be used with other types of small power tools, including those that have an oscillating output shaft, or many types of small tools which are particularly designed and configured to be connected to a dust hose that extends to a source of the vacuum and which is designed to carry dust and other small particulate matter away from the tool during use. 
         [0016]    While many tools purport to have such dust collection capability it is well known that the effectiveness and efficiency of many of them leave much to be desired. This is particularly true if the tool is one which is being used in a freehand manner where the tool is moved by the user, rather than being stationary with the work piece being crafted at a more or less stationary position. One of the detractions of many systems that are used with such handheld tools is the inability to keep the hose from being disconnected from the tool or from the vacuum source because of tension that is applied to the hose because the tool has been moved to a location beyond the reach of the dust hose or because the hose becomes caught on a work bench, table or other object in the area. 
         [0017]    Another consideration and potential for interconnection problems is that the dust hose that is attached to the tool may be required to be interfaced with a vacuum source that has a different sized duct hose. One particular product that is well known to consumers is the Shop Vac vacuum systems which have various sized hoses. Commonly available vacuum models of this type have any one of several diameters of vacuum hoses, including 1¼″, 1½″, 2¼″ and 2½″. Since the dust hose of such small handheld tools is often much less than the 1¼″ size, an adaptor is necessary for interconnecting the dust hose tool with the vacuum source dust hose. While such adaptors are known in the prior art, none has the compactness and convenience that is provided with the dust hose adaptor that is an embodiment of the present invention. 
         [0018]    Turning now to the drawings and particularly  FIG. 1 , an elongated power tool, indicated generally at  10 , is shown and has an elongated housing, indicated generally at  12 , a nose portion, indicated generally at  14 , and a rear end portion, indicated generally at  16 . The housing has a top surface  18 , side surfaces  20  and a bottom surface  22  and a motor is contained within the housing. The size of the housing  12  is such that most users can grip the tool with one hand with their fingers curling around under the bottom portion  22 . The rear end portion  16  is provided with a transverse extension  24  that includes a recess (not shown) for receiving a removable hose support, indicated generally at  30 . 
         [0019]    When a person is holding the tool  10  as described, their thumb is in position to operate a switch  32  which turns on the motor for operating the tool. The switch  32  is preferably designed so that can be slidingly moved between its ON and OFF positions. The tool  10  shown in  FIG. 1  has a power cord  34  that can be plugged into a source of AC power. It should be understood that power tools similar to that shown in  FIG. 1  may incorporate battery packs and in such event, they may be slightly larger. 
         [0020]    The tool  10  has an output shaft  36  that is rotatable and preferably is designed to have a collet nut or other attaching mechanism for holding a tool bit, such as a spiral cutting bit or the like. The tool  10  shown in  FIG. 1  also has a depth guide attachment device, indicated generally at  40 , that can be adjusted to control the depth of penetration of the tool bit that is mounted to the output shaft  36 . The depth guide  40  has a rear extension  42  that has an internal opening configured to receive a dust hose  44  in fitting engagement, with the opening communicating to an area adjacent the output shaft  36 . While not shown, the opening in the extension  42  is preferably circular in size so that the dust hose which preferably has a circular cross-sectional outer surface can be snuggly fit within the extension  42  so as to not be easily dislodged. The dust hose  44  is also shown in  FIG. 8  to have a plurality of adjacent ribs  46  that are separated by a smaller diameter recess  48 . The hose is preferably made of a material that permits some pressure to facilitate placing and removing the hose  44  from the extension  42 . More particularly, it is preferably made of a plastic material or a plastic-like material or rubber and one preferred material is polypropylene. As is shown in  FIG. 1 , the hose  44  is retained in the extension  42  of the depth guide  40  and is also retained in the hose support  30  at the rear end portion of the tool  10 . 
         [0021]    With regard to the hose support  30  shown in  FIGS. 2-4 , it has a releasable retaining clasp  50  that has a flexible tab  52  in its outer center portion thereof. The retaining clasp  50  is designed to fit within an aperture in the extension  24  of the rear end  16  of the housing  12  and is designed to be manipulated and released from the extension  24  if desired. The hose support  30  has a retaining clip portion  54  that is connected to the retaining clasp portion  50 , with the retaining clip portion  54  having a surface  56  that is designed and configured to seat against the outer surface surrounding the aperture in the extension  24 . It is shown to be slightly curved, but its actual shape is not particularly important so long as it facilitates the hose support snuggly fitting onto the extension  24 . The retaining clip  54  is shown to have sidewalls  58  which define a cylindrical opening  60  that extends slightly more than 180° of a cylindrical surface and as best shown in  FIG. 3  extend about 210°. The outer ends  62  of the sidewalls  58  are flared outwardly away from one another to present a larger opening in which the dust hose  44  can be inserted into the retaining clip  54 . The hose support  30  is preferably made of a plastic or plastic-like material such as glass filled nylon that has some flexibility so that the mounting clasp can be deflected during insertion and removal of the mounting clasp  50  into the aperture in the extension  24  and so that it may provide some amount of deflection of the sidewalls  58  when the dust hose  44  is inserted into the cylindrical opening  60  of the retaining clip  54 . The interior surface of the opening  60  has a raised rib  64  that extends substantially around the interior surface and is configured to protrude into the recesses  48  being adjacent ribs  46  of the dust hose  44 . This will prevent the hose from sliding out of the retaining clip portion  54  in the direction of the axis of the output shaft which can also be considered to be the axis of the tool  10  itself. The effect of the hose support  30  is to provide an additional support for the hose after it extends beyond the tool itself and prevents tension that might otherwise cause the friction fit of the dust hose  44  in the extension  42  to fail. 
         [0022]    As previously discussed, the dust hose  44  is functional, must be interfaced with a vacuum source and many users, including obvious and craftsmen alike, may employ a Shop Vac or similar device which has a larger hose than the dust hose  44  (claimed to be ¾″ to 1″ and that should be described earlier). The interconnection of the dust hose  44  and a Shop Vac hose can be strategically located to minimize the convenience of using a vacuum system for a user. In this regard, the waste of the larger diameter hose and its location may interfere with a user doing the intended work. A convenient location for the interconnection is often located on the user&#39;s body, such as near their belt. The dust hose  44  should be sufficiently long so that the user can extend his hands and arms fully, such as might occur when cutting holes in a ceiling or the like and therefore, the interconnection may conveniently support the weight of the vacuum source hose and not provide significant tension on the tool dust hose  44 . In this regard and referring to  FIGS. 5-7 , an adaptor, indicated generally at  70 , 
         [0023]    The adaptor  70  is compact in its design and is particularly suited to interconnect the dust hose  44  with any one of four different sized dust hoses from a Shop Vac or other vacuum source. The adaptor has an inlet portion  72  and an outlet portion  74  with the tubing connected together by a generally conical transition portion  76 . The inlet portion  72  has a chamfered inner surface  78  and an inner wall surface  80  that has a diameter that is approximately that of the outer diameter of the dust hose  44 . It is preferred that it gradually reduce in size from the outer end having the chamfer  78  so that the friction fit between the hose  44  will increase. The outlet portion  74  has an outer wall  80  and an inner wall  82  which are preferably concentric with one another. The outer thickness of each of the walls  80  and  82  are preferably sized so that the inner and outer surfaces of the walls correspond to either the inside or outside diameter of a standard commercially available Shop-Vac or similar product. Thus, the outside diameter of the wall  80  is defined by a surface  84  and the inside wall defined by a surface  86 . Similarly, the outside diameter of wall  82  is defined by surface  88  and the inside diameter is defined by the inside surface  90  with a thickness of approximately ¼″ for each of the inner and outer walls  80  and  82 , together with the diameters of the walls can result in friction fitting of Shop-Vac units having 1¼″, 1½″, 2¼″ and 2½″ commonly available sizes. The outer ends of both walls  80  and  82  are tapered as shown in  FIG. 7  which facilitates sliding the vacuum source dust hose onto the adaptor  70 . As shown in  FIGS. 5 and 6 , a belt clip  92  is provided on the outside wall of the outer portion  74  near the transition portion  76  so as not to interfere with the outer surface that the largest Shop-Vac hose may be slid onto. The belt clip  92  has an inner surface  94  and a clip portion  96  that is attached to the inner surface  94  at the top thereof  98 . 
         [0024]    The adaptor  70  is preferably also made with a plastic or plastic-like material or rubber, with the preferred material being polypropylene. The use of polypropylene allows some flexure in the overall structure and is not conducive to breaking or cracking under normal and expected use. The entire adaptor may be easily molded as a unitary object. 
         [0025]    While various embodiments of the present invention have been shown and described, it should be understood that other modifications, substitutions and alternatives are apparent to one of ordinary skill in the art. Such modifications, substitutions and alternatives can be made without departing from the spirit and scope of the invention, which should be determined from the appended claims. 
         [0026]    Various features of the invention are set forth in the following claims.