Abstract:
Methods and apparatus are described that provide an alternative to dust protection shrouds that must be clamped or be otherwise affixed to the body of a tool. The shroud captures and facilitates the removal of dust from an area being worked upon by a tool bit while being attached to the bit (not the tool itself). The shroud housing includes an exhaust orifice; a shaft receptive orifice through which the bit shaft may be passed and be coupled to the tool; and means, such as a ball bearing located on the edge of the shaft receptive orifice, for attaching the shroud housing to the shaft upon which it rides as the bit rotates. The tool independent dust protection methods and apparatus taught by the invention provide a one size fits all dust shroud that does not sacrifice build quality or structural integrity in favor of flexibility.

Description:
CONTINUITY INFORMATION  
       [0001]     This application claims the benefit of Provisional Application Ser. No. 60/758,310, filed Jan. 11, 2006, the complete disclosure of which is hereby incorporated by reference. 
     
    
     BACKGROUND OF THE INVENTION  
       [0002]     The invention relates generally to methods and apparatus for controlling exposure to dust during, for example, sanding, grinding and fabricating operations. More particularly, the invention relates to methods and apparatus that limit exposure to dust without requiring the fabrication or use of special purpose, tool specific, dust protection mechanisms commonly attached to the tool itself.  
         [0003]     Dust generated during the exemplary sanding, grinding and fabricating operations can be hazardous, often containing chromates, lead and other carcinogenic materials. At a minimum, the dust generated can cause respiratory issues when inhaled in quantity.  
         [0004]     For a number of years, different companies have created products to deal with dust collection. Sanders, for example, generally have a shroud which attaches to the body of the sander and covers the “backup pad”, i.e., the softer pad to which an abrasive is normally attached. Dust is typically drawn upwards through holes in, for example, an abrasive disc and then through corresponding holes in the backup pad. The dust may then be captured by, for example, vacuum suction, and be channeled through the shroud to an exhaust.  
         [0005]     The above described shroud approach works well on sanders; but becomes complex and less effective when, for example, used with right-angled grinders and other tools. On these types of tools one accepted approach is to create a shroud which is specific to the tool on which it will be used. For example, it is known in the prior art to create an aluminum or plastic mounting fixture which can clamp to the body of a tool in order to support a vacuum shroud hanging below, over, for example, an abrasive disc.  
         [0006]     Many different tool clamp on type shrouds have been manufactured; however, it is required that the shroud be designed to fit the tool for which it is intended.  
         [0007]     It is also known to manufacture “one size fits all” type shrouds for grinders of various makes and sizes. However, this approach relies on a stepped shroud which can be trimmed or adjusted to fit a given tool. This is a true one size fits all, but sacrifices build quality and structural integrity in favor of flexibility. Moreover, this type of shroud is once again a tool clamp on type shroud, i.e., the shroud is joined to the tool via a mechanism that clamps the shroud to the tool body.  
         [0008]     Examination of tools on the market indicates that the characteristics that are universal among all tools are the air input (¼ MNPT) and the size of the shank that is captured by the collet. In order to create a shroud that will truly fit any tool on the market, it is desirable to incorporate these commonalities into the solution.  
         [0009]     Finally, non of the known dust protection shrouds is “tool independent”, defined herein to mean a shroud that is not tool design specific and does not have to be attached (for example be clamped) to the tool body in order to provide the desired dust protection.  
       SUMMARY OF THE INVENTION  
       [0010]     It is an object of the invention to provide tool independent methods and apparatus for providing dust protection.  
         [0011]     It is a further object of the invention to provide a one size fits all dust shroud that does not sacrifice build quality or structural integrity in favor of flexibility.  
         [0012]     It is another object of the invention to provide an alternative to tool specific dust prevention solutions such as special purpose shroud designs and attachment mechanisms per tool.  
         [0013]     It is still a further object of the invention to provide methods and apparatus that facilitate the floating attachment and positioning of a dust protection shroud on a tool bit shaft to thereby allow the shroud to maintain its position over a work area by riding on the shaft; rather than by making a physical or mechanical connection to the tool itself.  
         [0014]     It is yet another object of the invention to provide methods and apparatus that prevent a dust shroud using the aforementioned floating attachment to a tool bit shaft, from spinning on the bit as the shaft rotates.  
         [0015]     Further still, it is an object of the invention to provide methods and apparatus that allow a shroud riding on the shaft of a tool bit to maintain a variable distance between the shroud and the tool work area.  
         [0016]     Furthermore, it is an object of the invention to provide methods and apparatus for providing dust protection solutions in which a given shroud used on a tool bit shaft is always fixed in position by its coaxial relationship to the shaft although the shape of the shroud may be varied to meet new and different application.  
         [0017]     The dust protection shroud and associated methods for its use, as contemplated by the invention, are clearly distinguishable over the prior art by virtue of the shroud being attached to a tool bit (not the tool itself).  
         [0018]     In accord with aforestated object, which will be discussed in detail below, a first aspect of the invention provides a dust protection shroud for capturing and facilitating the removal of dust from an area being worked upon by a tool bit (itself removably coupled via, for example, an integral tool bit shaft to a given tool), where the shroud includes (a) a shroud housing that further includes an exhaust orifice and a shaft receptive orifice through which the tool bit shaft may be passed for coupling to the tool; along with (b) means for attaching the shroud housing to the tool bit shaft.  
         [0019]     The means for attaching contemplated by this first aspect of the invention includes, according to an illustrative embodiment of the invention, means for suspending the shroud housing on the shaft.  
         [0020]     According to a further illustrative embodiment of this first aspect of the invention, a ball bearing operative to press in toward the center of the shroud housing, with the ball bearing being located on the periphery of the aforementioned shaft receptive orifice, may serve as a means for suspending the shroud housing on the shaft. This would enable the housing to “float” above the area being worked upon by the tool bit as the tool bit shaft spins within the ball bearing.  
         [0021]     Further still, in accordance with yet another illustrative embodiment of this first aspect of the invention, the shroud housing is not tool design specific and is operative to maintain its position over the area being worked by the tool bit without being attached to the tool, i.e., is tool independent as defined hereinabove.  
         [0022]     Further yet, in accordance other illustrative embodiments of this first aspect of the invention, the shroud housing is operative to maintain its position over the work area by riding on the tool bit shaft; is operative to maintain a variable distance from the work area by sliding up and down the tool bit shaft; and may be varied in shape dependent on application while maintaining a fixed position relative to the tool bit shaft defined by the shroud&#39;s coaxial relationship therewith.  
         [0023]     According to a second aspect of the invention, apparatus for providing protection from dust produced when using a given tool is described which includes (a) a tool bit having a shaft that is removably coupled to the tool; (b) a shroud; and (c) means for suspending the shroud on the shaft.  
         [0024]     According to a third aspect of the invention, a tool independent dust protection shroud is described that includes (a) a shroud housing; (b) means for enabling said shroud housing to float on the shaft of a tool bit; and (c) an exhaust orifice through which dust collected within the shroud housing may be removed.  
         [0025]     According to a fourth aspect of the invention, a method for capturing and removing dust from an area being worked upon by a tool bit is provided. The tool bit itself includes a shaft that allows the tool bit to be removably coupled to a tool. The method contemplated by this fourth aspect of the invention includes the steps of (a) attaching a dust protection shroud to the tool bit shaft; and  
         [0000]     (b) coupling the tool bit shaft to a tool. According to an illustrative embodiment of this aspect of the invention, the shroud “floats” on the tool bit shaft.  
         [0026]     Further steps contemplated by various (but not necessarily all) embodiments of this fourth aspect of the invention include removing dust captured within the shroud via a shroud exhaust orifice; removing the dust under the influence of a vacuum; and using the vacuum to prevent the shroud from spinning on the shaft to which it is attached.  
         [0027]     According to a fifth aspect of the invention a method for capturing and removing dust from an area being worked upon by a tool bit having an integral shaft, utilizing a dust protection shroud housing, is described. The method contemplated by this fifth aspect of the invention includes the steps of (a) passing the shaft through the shroud housing; (b) suspending the shroud housing on the shaft; (c) coupling a vacuum source to the shroud housing; and (d) coupling the tool bit to the tool via the shaft.  
         [0028]     The invention features methods and apparatus that provide an alternative to dust shrouds that need to be clamped or be otherwise affixed to the body of a tool. Accordingly, an advantage of the invention is that it works well, for example, on right angle grinders and other tools.  
         [0029]     Further advantages and features of the invention include, but are not limited to, tool independent methods and apparatus for providing dust protection; the provision of a one size fits all dust shroud that does not sacrifice build quality or structural integrity in favor of flexibility; an alternative to tool specific dust prevention solutions; methods and apparatus that facilitate the floating attachment and positioning of a dust protection shroud on a tool bit; and the provision of methods and apparatus that (a) prevent a dust shroud, having the aforementioned floating attachment to a tool bit shaft, from spinning on the bit; (b) allow a shroud riding on the shaft of a tool bit to maintain a variable distance between the shroud and the tool work area; and (c) allow the shape of a shroud to be varied to meet new and different applications. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0030]     The above and other objects, features and advantages of the invention will be apparent upon consideration of the following detailed description, taken in conjunction with the accompanying drawings, in which like reference characters refer to like parts throughout.  
         [0031]      FIGS. 1A-1E  depict exploded side views of various tool, tool shaft and shroud combinations contemplated by the various aspects of the invention;  
         [0032]      FIG. 2  is an exploded side view of an exemplary embodiment of the invention depicting a shroud housing suitable for attachment to a tool shaft and a vacuum hose, all in combination with an exemplary right angle grinder;  
         [0033]      FIG. 3  is a top perspective view of an exemplary shroud housing and ball bearing combination of the type depicted in  FIG. 2  and contemplated by the invention;  
         [0034]      FIG. 4  is a side view of an exemplary assembled tool, tool bit and shroud combination of the type depicted in  FIG. 2  and contemplated by the invention.  
         [0035]      FIG. 5  is a perspective view of an exemplary shroud housing, ball bearing and shaft combination of the type depicted in  FIG. 2  and contemplated by the invention; and  
         [0036]      FIG. 6  is a bottom perspective view of an exemplary shroud housing and ball bearing combination of the type depicted in  FIG. 2  and contemplated by the invention. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0037]     As indicated hereinbefore, the shroud (and associated methods for its use) contemplated by the invention is not mounted on the tool itself. Instead the shroud attaches to the shaft of the tool&#39;s bit.  
         [0038]     The shroud has, according to an illustrative embodiment of the invention, a ball bearing pressing into its center. The shaft of the bit spins within the ball bearing. The shroud is suspended on the shaft, and as the tool spins the shaft, the ball bearing center allows the shroud to “float” above the abrasive or cutting disc beneath.  
         [0039]     According to one embodiment of the invention, a vacuum hose connected to the shroud&#39;s exhaust can be utilized to provide enough force to prevent the shroud from spinning on the rotating bit. Again, the shroud, in accordance with this illustrative embodiment of the invention, is not in any way connected to the tool itself. Because it is not dependent on tool design it can be used with any tool.  
         [0040]     Turning to the drawing, as indicated hereinabove,  FIGS. 1A-1E  depict exploded side views of various tools, tool shaft and shroud combinations contemplated by the various aspects of the invention.  
         [0041]     In particular,  FIG. 1A-1C  depict a router  100 , grinder  102  and drill  103 , respectively, each along with an exemplary dust protection shroud, illustrative of the principals of the invention, suitable for attachment to the depicted tool bits. In  FIG. 1A , shroud  104  may be seen as interposed between router  101  and router bit  105 . Rather then being mounted onto the tool (router  101 ), the invention contemplates attaching shroud  104  (to be described in detail hereinafter with reference to  FIGS. 2-6 ), tool shaft bit portion  105   a  of router bit  105 .  
         [0042]     In  FIG. 1B , shroud  107  may be seen as interposed between grinder  102  and, for example, radial disc  108 . Once again, in accordance with the teachings of the invention, shroud  107 , rather than being mounted onto the tool (grinder  102 ), the invention contemplates attaching shroud  107  to shank  108   a  of the tool bit (in this case, redial disc  108 ). Also shown in  FIG. 1B , for the sake of illustration, is flexible shaft  106 , coupled to grinder  102 . Flexible shaft  106  may be used in conjunction with shroud  107  and illustrative radial disc  108  in order to be able to more conveniently use the tool and dust protection shroud combination in those applications where extended reach and flexibility are required.  
         [0043]      FIG. 1C , like  FIGS. 1A and 1B , depicts an exploded side view of a tool, dust protection shroud and tool bit combination of the type contemplated by the invention. As indicated hereinabove, drill  103  is depicted in  FIG. 1C . Also shown in  FIG. 1C  is, in accordance with the teachings of the invention, shroud  109  interposed between drill  103  and drill bit  110 . Once again, in accord with the teachings of the invention, shroud  109  is intended to be attached to drill bit  110 ; and not drill  103 .  
         [0044]     Attention is directed to  FIGS. 1D-1E  which each depict an exploded side view of other exemplary tool, shroud and tool bit combinations that incorporate the teachings of the invention.  
         [0045]     In particular,  FIG. 1D  depicts a right angle grinding tool, grinder  111 , which will be discussed in greater detail hereinafter with reference to  FIGS. 2-6 . The combination depicted in  FIG. 1D  includes grinder  109  and shroud  112  which, in accordance with the teachings of the invention, may be attached to bits like drill bit  113  or grinding disc  114  (with the shroud being attached on shank  114   a  of grinding disc  114 ).  
         [0046]      FIG. 1E  depicts another grinder tool, grinder  115 , in combination with collet  116 ; with a shroud  117  interposed between grinder  115  and one of 3 other illustrative die grinder bits: tool bit  118  having an integrated tool bit shaft  118   a ; tool bit  119  having an integrated tool bit shaft  119   a ; and tool bit  120  having an integrated tool bit shaft  120   a . In accord with the teachings of the invention, the shaft of a selected tool bit is passed through shroud  117  and is attached (the tool bit shaft) to collet  116 . Shroud  117  is not attached to the tool; but rather is attached, for example by the aforementioned ball bearing attachment, to the shaft so as to allow the shroud to float thereon as the bit spins.  
         [0047]     The dust protection components and assemblies shown in  FIGS. 2-6  are meant to illustrate the principals of the invention in the context of an exemplary 2 inch right angle grinder. The shroud depicted in  FIGS. 2-6  may also be used, in accordance with the teachings of the invention, for a straight line tool, like a die grinder or an angled too. The tool is not important, as long as it is designed to rotate.  
         [0048]     As indicated hereinbefore,  FIG. 2  is an exploded side view of an exemplary embodiment of the invention depicting a shroud housing  205  suitable for attachment to a tool shank  210  and a vacuum hose  209 , all in combination with an exemplary right angle grinder  201 .  
         [0049]     The illustrative right angle grinder  201  is shown having a conventional quick disconnect air intake  202 . Further, collet  204  is shown with right angle tool head  203 , with collet  204  being designed to receive shank  210  to which shroud housing  205 , in accordance with the teachings of the invention, is attached, after passing shank  210  through the open bottom of shroud  208  (shown at  208   a  and in greater detail in  FIG. 6 ) and through the center of depicted shaft receptive orifice  207  of shroud  208 , through ball bearing  206 . Once again, as indicated hereinabove, the shroud (and associated methods for it&#39;s use) contemplated by the invention is not mounted on the tool itself. Instead the shroud attaches to depicted tool shank  210 .  
         [0050]     Shroud  208  has, according to this illustrative embodiment of the invention, ball bearing  206  pressing into its center. Tool bit shank  210  is designed to spin within ball bearing  206  and as ball bearing  206  presses inward against shaft  210 , shroud  208  is suspended on the shaft. As the tool spins the shaft, the ball bearing center allows the shroud to “float” above the abrasive or cutting disc, like depicted disc  213 , beneath. Also shown in  FIG. 2  are an exemplary hard back up pad  212 , typically included in combination with grinding tools.  
         [0051]     As indicated hereinbefore, in accord with the teachings of the invention, vacuum hose  209  connected to a shroud exhaust (shown as exhaust orifice  214  in the shroud housing  208  depicted in  FIG. 2 ), may be utilized to provide enough force to prevent the shroud from spinning on the rotating bit. Once again, the shroud, in accordance with this illustrative embodiment of the invention, is not in any way connected to the tool itself. Because it is not dependent on tool design it can be used with any tool.  
         [0052]     Turning attention to  FIG. 3 , a top perspective view of an exemplary shroud housing and ball bearing combination of the type depicted in  FIG. 2  is shown.  
         [0053]     In accord with the teachings of the invention, depicted shroud housing  301  is shown to include exhaust orifice  302 , shaft receptive orifice  304 , through which a tool bit shaft may be passed and be coupled to given tool; and the exemplary ball bearing attachment means  303 , which in operation presses in toward the center of orifice  304  depicted in  FIG. 3 . Again, as a tool bit spins within ball bearing attachment means  303 , the ball bearing pressing inward against the shaft allows the shroud housing to be suspended thereon.  
         [0054]     Referring to  FIG. 4 , a side view of an exemplary assembled tool, tool bit and shroud combination of the type depicted in  FIG. 2  and contemplated by the invention, is shown.  
         [0055]     In particular, the depicted right angle grinder  401  is shown assembled to include air intake  402 , tool head  403 , collect  405 ; and shroud  406  which, in accord with the teachings of the invention, is attached to a tool bit shaft passing there through.  
         [0056]     Turning to  FIG. 5 , a perspective view of an exemplary shroud housing  501  is shown in combination with ball bearing attachment means  503  and shaft  504  combination of the type depicted in  FIG. 2  and contemplated by the invention. Also depicted in illustrative  FIG. 5  is exhaust orifice  504  to which a vacuum hose (not shown) may be connected.  
         [0057]     Finally, as indicated hereinbefore,  FIG. 6  is a bottom perspective view of an exemplary shroud housing  601  and ball bearing combination of the type depicted in  FIG. 2  and contemplated by the invention. In particular, the aforementioned open bottom of a shroud housing, like open bottom  605  of shroud housing  601  (referred to as  208   a  in  FIG. 2 ), is depicted in  FIG. 6 ; along with ball bearing attachment means  602 , shaft receptive orifice  603 , and exhaust orifice  604 , all serving the purposes hereinbefore described.  
         [0058]     It should be noted that the shape and size of a shroud (shroud housing) can be changed to meet the needs of different bits. For example, the same rotary tool might be used for a ¾ inch, 1 inch, 1.5 inch, 2 inch, 3 inch or any other suitable size abrasive dis. The shroud would be sized differently depending on the size of the bit being used. The shroud might be used on a tool with ¼ inch shank, but may also be used on other size shanks, both larger and smaller in diameter. The bearing size is also subject to change based on the application.  
         [0059]     Further, it will be appreciated by those skilled in the art that the tools described herein may be powered, for example, by compressed air, electricity, mechanically or other means.  
         [0060]     Applications for the invention include, but are not limited to, sanding with a right angle tool or a straight line tool; grinding with a right angle tool or a straight line tool; using the shroud to collect chips and dust from routers of any size or configuration; surface preparation or corrosion removal using radial discs or radial bristle discs or other surface preparation discs.  
         [0061]     There have been described and illustrated herein tool independent dust protection apparatus and associated dust protection methods. While particular embodiments of the invention have been described, it is not intended that the invention be limited thereto, as it is intended that the invention be as broad in scope as the art will allow and that the specification be read likewise. It will therefore be appreciated by those skilled in the art that certain modifications could be made to the provided invention without deviating from its spirit and scope as so claimed.