Tapering device for removing portions of a gypsum board

A device 10 and method for forming a non-tapered end 12 of a gypsum board 14 into a tapered configuration or portion 16 includes a rotary drive tool 18 that imparts rotary motion to a tool bit 20 removably secured thereto, a pair of oppositely disposed angle members 22 having cooperating base portions 24 configured to promote attaching a dust collection collar 17 to the base portions 24, the angle members 22 disposing and guiding the rotating tool bit 20 between outer paper walls 28 of a non-tapered end 12 of the gypsum board 14 to ultimately severe portions of gypsum from the non-tapered end 12 thereby forming a recess 32 without damaging the outer paper walls 28 of the gypsum board 14. The device 10 and method ultimately removes severed portions of gypsum from the recess 32, whereupon, the non-tapered end 12 of the gypsum board 14 is forcibly bent to form a tapered configuration, end edges 128 of the board 14 are secured together with tape 122 to prevent the board 14 from returning to a non-tapered configuration, and the gypsum board 14 is secured to a support structure 38 such that tapered portions 16 of adjacent gypsum boards 14 cooperate to promote a planar finished seam when tape and joint compound are applied thereto.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates generally to tapering devices and, more particularly, to tapering devices for removing portions of gypsum from edge portions of a non-tapered end of a gypsum board thereby configuring opposing protuberances with a recess therebetween to allow the protuberances to be forcibly joined together to form a tapered end when the gypsum board is secured to a support structure.

2. Background of the Prior Art

Gypsum board is commonly used to provide a finished wall surface for interior rooms of a house, office building or similar structure. Upon securing the gypsum board to wall studs, the resulting joints are taped, covered with a joint compound, then smoothed and finished so as to be undetectable after a coat of paint has been applied. Typically, the gypsum board includes a tapered edge portion that extends along the longitudinal sides of the board. The tapered edge portions of adjacent gypsum boards form a relatively shallow “V” shaped configuration that promotes a smooth undetectable seam after adding tape and finishing compound.

A problem arises when gypsum boards are cut and secured to a support structure such that non-tapered “butt” edges are adjacently positioned. A relatively high degree of skill and considerable additional time are required to tape and apply joint compound to non-tapered joints. However, irrespective of the degree of care exercised when covering a non-tapered joint, a noticeable “hump” or “crown,” will ultimately form on the seam. Further, when a gypsum board is cut, the remnant portion ordinarily will be discarded due to a lack of taper at the cut portion that would ultimately adjoin a tapered portion of an already installed gypsum board.

A need exists in the art for a device and/or method for forming a non-tapered end of a gypsum board into a tapered configuration whereby the gypsum board can be disposed adjacent to a tapered portion of an already installed gypsum board, whereupon, the adjacent tapered ends are taped and covered with joint compound, then sanded to a smooth planar surface thereby eliminating the hump or crown of the present method of installing gypsum boards.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide a tapering device that allows a non-tapered end of a gypsum board to be formed into a tapered configuration thereby overcoming many of the disadvantages of the prior art.

A principal object of the present invention is to provide a tapering device that removes or cuts a predetermined quantity of gypsum from between paper walls of a gypsum board. A feature of the device is a tapered tool bit that is detachably secured to a rotary drive tool. An advantage of the device is that it configures a recess in the edge portion of the gypsum board that forms two protuberances such that upon forcibly joining the protuberances together on a support structure, the result is a tapered end portion having a predetermined cross-sectional configuration.

Another object of the present invention is to remove gypsum dust from the recess cut into the gypsum board. A feature of the device is a dust collection collar that is detachably joined to a drive end of the rotary drive tool. The dust collection collar includes a suction end that is secured to a suction hose of a vacuum system. Another feature is spiral channel formed in the tapered tool bit to lift gypsum dust from the recess. An advantage of the device is that the removal of gypsum dust from the recess promotes the forcible joining of the protuberances.

Still another object of the present invention is to position the drive tool-tool bit assembly upon the edge of the gypsum board. A feature of the device is a pair of opposing angle members that are detachably joined to the dust collection collar. An advantage of the device is that the tool bit is centered between the paper walls of the gypsum board thereby preventing the protuberances from breaking when forcibly joined together upon securing the gypsum board to a support structure.

Yet another object of the present invention is to provide a member that removes gypsum dust from the recess after the drive tool-tool bit assembly has been removed from the recess. A feature of the device is a dust vacuum attachment that removes gypsum dust from the narrowest portions of the freshly cut recess. An advantage of the device is that by removing gypsum dust from the narrowest of regions of the recess, the protuberances may be forcibly joined together without damage when the gypsum board is secured to a support structure.

Another object of the present invention is to provide a method that includes a tool bit member with a flared end portion. A feature of the method is an enlarged cavity at the bottom of a tapered recess formed in an end portion of a gypsum board, the tapered recess and enlarged cavity being formed by the tool bit being rotated and guided between outer walls of the end portion of the gypsum board. Another feature of the method is that the tool bit is “slid” across the end portion of the gypsum board such that the rotating tool bit is initially parallel to a side edge of the end portion thereby disposing the flared end portion distally from an end edge of the end portion. An advantage of the method is that the enlarged cavity is formed distally from the end edge of the end portion of the gypsum board, the enlarged cavity extending laterally across the end portion of the gypsum board a predetermined and parallel distance from the end edge. Another advantage of the method is that by sliding the tool bit laterally across the end portion, the flared end portion of the tool bit member does not form an enlarged “starter hole” from the end edge into the end portion to a depth equal to the length of the tool bit. An advantage of the enlarged cavity extending laterally across the end portion of the gypsum board without a starter hole is that the recess separated outer walls of the end portion readily bends to configure an uniform tapered end portion of the gypsum board, the tapered end beginning at the enlarged cavity and ending at the end edge of the board. Avoiding a starter hole reduces the possibility of the gypsum board initially bending somewhere along the longitudinal axis of the starter hole resulting in a non-uniform bending and inconsistent taper of the end portion of the gypsum board.

Briefly, the invention provides a device for removing portions of a gypsum board to allow non-tapered end portions of the board to be tapered upon installing the gypsum board comprising a rotary drive tool; a tool bit removably secured to said rotary drive tool, said rotary drive tool imparting rotary motion to said tool bit; means for guiding said rotating tool bit through an end portion of the gypsum board whereby a portion of gypsum is severed from the end portion without damage to opposing paper walls of the gypsum board; and means for removing the severed portion of gypsum from the gypsum board whereby a recess is configured that allows the end portion to become tapered when the end portion is secured to a support structure.

The invention further provides a method for tapering an end portion of a gypsum board, said method comprising the steps of providing a tool bit having a flared end portion; providing means for rotating said tool bit; guiding said rotating tool bit between outer walls of the gypsum board such that a predetermined portion of the gypsum board is removed thereby forming a recess across a predetermined end portion of the gypsum board, said recess having an enlarged inner portion that corresponds to the configuration of said flared end portion of said tool bit; and bending at least one outer wall of the gypsum board after removing the predetermined portion of the gypsum board whereby a tapered end portion of the gypsum board is formed.

Also, the invention provides a method for tapering gypsum board, said method comprising the steps of forming a recess between outer walls of a predetermined end portion of a gypsum board, said recess having a configuration that includes an enlarged cavity disposed across said end portion a predetermined distance from an end edge of said end portion of the gypsum board; and bending at least one of the outer walls of the gypsum board via said enlarged cavity whereby a tapered gypsum board is formed.

Further, the invention provides a method for tapering gypsum board end portions, said method comprising the steps of:

providing a tool bit having an enlarged end portion;

providing means for rotating said tool bit;

guiding said rotating tool bit between outer walls of a gypsum board, said rotating tool bit initially engaging a side edge of the gypsum board and proceeding laterally through an end portion of the gypsum board until exiting the gypsum board via an opposite side edge whereby a recess with an enlarged inner cavity is formed; and

bending at least one recess forming outer wall of the end portion of the gypsum board via said enlarged cavity whereby the end portion of the gypsum board becomes tapered to facilitate a planar seam upon the application of tape and joint compound to adjacent tapered end portions of adjacent gypsum boards.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring now to the drawings and in particular toFIGS. 1–9, a tapering device10that allows a non-tapered end12of a plaster board, drywall or gypsum board14to be formed into a tapered configuration16, includes a rotary drive tool18that imparts rotary motion to a gypsum cutting tool bit20that is removably secured to the rotary drive tool18, a pair of oppositely disposed angle members22having cooperating base portions24attached to a dust collection collar17. The dust collection collar17is fabricated from plastic or similar rigid, deformable material, and is configured to be detachably joined to a drive end19of the rotary drive tool18. The angle members22dispose and guide the rotating tool bit20between outer paper walls28of the non-tapered end12of the gypsum board14to ultimately severe portions of gypsum from the non-tapered end12thereby forming a recess32without damaging the paper walls28. The tool bit20removes the severed portions of gypsum from the recess32via a spiral channel34circumferentially disposed about the tool bit20. A vacuum system36removes the severed portions of gypsum from the gypsum board14when the tool bit “lifts” the severed portions from the recess32. The non-tapered end12is then forcibly bent to form a tapered configuration16upon the securing of the non-tapered end12to a support structure38.

The rotary drive tool18is a typical, commercially available hand held power tool similar to the power tools sold by Roto Zip Tool Corporation located at 1861 Ludden Drive, Cross Plains, Wis. The rotary drive tool18includes a collet that snugly grasps and holds a hexagonally configured drive end40of the gypsum cutting tool bit20. The gypsum cutting tool bit20is fabricated from a standard high speed, one-quarter inch diameter, carbon steel drill bit by utilizing manufacturing methods well known to those of ordinary skill in the art. One method includes disposing the standard drill bit on a CNC or End Mill Puller machine, whereupon, the machine removes metal stock from the periphery60of the tool bit to form the required tapered configuration for the resulting gypsum cutting bit20, then deepens the flutes or spiral channel34in the drill bit over the length of the drill bit to a position proximate to a relatively pointed end58such that the end58maintains structural integrity while promoting the removal of gypsum when cutting the recess32into the gypsum board14.

The standard drill bit is tapered to replicate the industry standard for tapering end portions of gypsum board. More specifically, a typical gypsum board14, irrespective of thickness, includes an end portion16having a two and one-half inch lateral dimension that is tapered one-eighth of an inch for the entire two and one-half inches (seeFIGS. 9A–9C). Thus, the gypsum cutting bit20must have a cutting portion of at least two and one-half inches in axial length with a taper of one-eighth of an inch over that same two and one-half inches of axial length. Obviously, should the gypsum board14taper dimensions vary, the taper dimensions of the bit20will correspondingly vary. Also, the configuration of the bit20and the resulting recess32may vary (as detailed inFIGS. 6A–6C) to provide a required taper for boards14of varying thickness.

After tapering the tool bit20, the spiral channels34will be machined to a depth of substantially about one-twelfth of an inch to promote the removal of the gypsum dust from the recess32by the bit20rotating in a cooperative direction. Further, the deeper channels34allow the corresponding periphery of the bit20to cut the gypsum board to configure the required recess32in the non-tapered end12. The channels34will not be modified near the end58of the bit20to maintain structural integrity, however, due to insufficient channel depth, the bit20will not be able to remove gypsum dust in the narrow portions of the recess32formed by the end58of the bit20. The tapered tool bit20with the deeper channels34is suitable for total immersion into the gypsum board and/or gypsum dust, a feature that standard drill bits do not possess.

Referring now toFIGS. 11–14, the dust collector17slides over the drive end19of the rotary drive tool18such that a key guide slot13is aligned with a key on the drive end19of the drive tool18. A threaded shaft100is fed through a clamp flange102into a lock nut104, whereupon, the shaft100is tightened into the lock nut104thereby securing the dust collection collar17onto the drive end19of the rotary drive tool18. The collector17is configured and dimensioned to promote the collection of cut gypsum dust removed from the recess32by the tool bit20, and to direct the discharge of the dust through a suction end44and into a hose member36of a vacuum system.

After joining the dust collection collar17to the drive end19of the drive tool18, the hose member36is removably secured to the suction end44of the collection collar17. An opposing end of the hose member36is secured to a typical suction member (not shown) of any vacuum system utilizing a standard industrial vacuum hose. The suction end is disposed to promote the removal of severed portions of gypsum from the gypsum board14, as the severed portions are removed from the recess32by the tool bit20. The angle members22are configured to facilitate the securing of the angle members22irrespective of the distance separating inner walls48of board engagement portions50of the angle members22. The position of the each angle member22is adjusted via slots52disposed through the base portion24. The dust collection collar17is ultimately secured to the base portions24via securing bolts54inserted through the slots52and nuts56snugly tightened upon the bolts54.

The angle members22are fabricated from rigid, light weight material suitable to maintain alignment with the centered tool bit20, and sufficiently durable to tolerate the weight and vibrations generated by the rotary drive tool18and the tool bit20secured thereto. The angle members22are configured to provide the base portion24with a lateral dimension that cooperatively accepts a predetermined longitudinal dimension of the slots52. The angle member22configuration also provides the board engagement portions50with a longitudinal dimension, when taking a side view (FIG. 2), that extends the angle member22beyond a relatively pointed cutting end58of the tool bit20, and with an inner wall48surface area that promotes stability when the inner walls48snugly engage the outer paper walls28of the gypsum board14after the angle members22have been adjustably secured to the dust collection collar17to facilitate the cutting of the recess32in the non-tapered end12of the gypsum board14.

The tool bit20is fabricated from steel or similar hard metal that enables the pointed cutting end58or side periphery60to cut gypsum. The tool bit20tapers from the hexagonal drive end40to the pointed or small radius cutting end58that penetrates the plaster between the outer paper walls28. The taper of the tool bit20is such that the outer diameter of the drive end40is relatively larger than the outer diameter near the cutting end58thereby promoting a corresponding “sharp” taper to the gypsum board14that is identical to the manufactured taper of the gypsum board14when the board14is nailed, screwed or otherwise secured to the support structure38which is typically wood or lightweight steel. The circumferentially disposed spiral channel34in the tool bit20is configured to extract, when rotating, portions of gypsum and dust from the recess32. The portions of gypsum and dust resulting from the tool bit20engaging gypsum between the outer paper walls28when cutting the recess32into the non-tapered end12of the gypsum board14.

In operation, an individual selects a gypsum board14having a non-tapered end12that will ultimately abut a gypsum board14with a tapered configuration16that is secured upon a support structure38. To promote a shallow “V” configured surface along the junction of the two boards14, the non-tapered end12must be modified to include a recess32that allows the non-tapered end12to become tapered when the non-tapered end12is secured to the support structure38. The recess32is formed by the individual holding the rotary drive tool by a handle62with the securing bolts and nuts54and56loosened to allow a bottom portion64of the angle members22to slide upon the outer paper walls28of the gypsum board14until the tip58of the tool bit20is disposed adjacent to the gypsum66and equidistant (for a one-half inch thick gypsum board14) between the outer paper walls28. The bolts54are then tightened to lock the position of the angle members22. The rotary drive tool18is energized to rotate the tool bit20, whereupon the tool bit20is forcibly inserted into the solid gypsum66by the individual until a bottom wall68of the dust collection collar17is disposed proximate to the gypsum66.

The recess32cut in a one-half inch thick (or thinner) gypsum board14is disposed at a proximate mid-portion of the board14(seeFIG. 15). For five-eighths or three-quarter inch thick boards14(seeFIGS. 16 and 17, respectively), the recess32would be disposed closer to the outer wall28that will be ultimately “bent” to form the tapered portion of the board14when the board14is secured to a support structure38. The corresponding protuberances94are difficult to bend for the thicker boards14(FIGS. 16 and 17) should the recess32be disposed equidistant between the outer walls28. Therefore, the thickness of the bendable protuberance94is the same for each of the boards14irrespective of thickness. Obviously, the thicker the board14, the greater the distance between the recess32and the side wall28engaging the support structure38.

The angle members22are then forcibly slid upon the outer paper walls28while the tool bit channel34rotates and cuts through the gypsum66and at the same time, removes the resulting gypsum dust to ultimately form the recess32. After the recess32has been formed through the entire non-tapered end12of the gypsum board14, the board14is secured upon the support structure38via nails70, screws or similar securing means. As the non-tapered end12is secured in position by the securing means, the non-tapered end12starts to collapse thereby forming an angle or taper. After the plaster board14has been tightly secured to the support structure38, the non-tapered end12has totally collapsed to form a tapered configuration16that cooperates with an abutting adjacent tapered gypsum board14to receive tape71and plaster72upon adjoining outer paper walls28to ultimately provide a smooth, planar surface that is undetectable after the entire surface of the gypsum boards14is painted.

Referring now toFIGS. 10A–D, a dust vacuum attachment member80is depicted. The member80is sized to fit snugly into the recess32and is used to remove gypsum dust that collects in narrow portions of the recess32after the tool bit20has been removed from the recess32. The dust that collects in the narrow portions of the recess32is generally not removed by the tool bit20. More specifically, the spiral channels34in the tool bit20rotate to remove or “lift” the dust from the recess32up to the dust collection collar17whereupon the vacuum system removes the dust via the suction end44of the collar17. The relatively shallow depth of the spiral channel34at the point58of the tool bit20inhibits physically moving the dust thus preventing the dust from being lifted from the narrow portions of the recess32.

The member80is made from plastic or similar rigid material, and includes a cylindrical hose portion82with a cavity83therein that snugly inserts into and is removably secured to the suction hose36of a vacuum system. Besides the hose portion82, the member80includes an elongated recess portion84having a front wall86with relatively large longitudinal and lateral dimensions, a substantially “V” configured side wall88with a relatively small lateral dimension in comparison to the front wall86, and an aperture90extending longitudinally through the recess portion84. The configuration of the recess portion84disposes a suction end92adjacent to the narrow bottom93of the recess32to promote the removal of gypsum dust. Removing gypsum dust, prevents breakage or other damage to two opposing protuberances94that are forcibly urged together when securing the gypsum board14to a support structure38thereby providing a tapered configuration16. The protuberances94result from the cutting of the recess32into an edge portion96of the gypsum board14(see FIGS.6and6A–6C).

The suction end92includes a series of notches or apertures98that promote the insertion of the suction end92into a relatively large amount of gypsum dust that has accumulated in the recess32during the cutting of the recess32into the edge portion96of the gypsum board14. The notches98increase the surface area of the suction end92to reduce the amount of time required to remove all the gypsum dust from the recess32after energizing the vacuum system.

Referring now toFIGS. 18–26, an alternative device and method for tapering an end portion of a gypsum board14in accordance with the present invention is depicted.FIG. 18depicts the tool bit20ofFIG. 5, but with a flared end or end portion110. The flared end110forms a corresponding enlarged cavity112at the bottom or inner portion of the tapered recess114formed by the tool bit20. The placement of the cavity112corresponds to the bend or “snap” portion of the gypsum board14where the installer forcibly bends one of the outer walls116of the recess114at the end of the gypsum board14to form a tapered end portion118. Although both outer walls116and117could be bent to taper the end portion118, the preferred method is to bend only one outer wall116because the opposing outer wall117must remain planar to facilitate contact with a support structure120to allow a plurality of fasteners124to secure the gypsum board14to the support structure120, typically a “two-by-four.”

The enlarged cavity and tapered recess112and114are formed by the tool bit being rotated and guided between the outer walls116and117of the end portion118of the gypsum board14. The tool bit20is ultimately “slid” across the end portion118of the gypsum board14such that the rotating tool bit20is initially parallel to a side edge126of the end portion118thereby disposing the flared end110distally from an end edge128of the end portion118. The enlarged cavity112relieves pressure when bending the outer wall116toward the adjacent outer wall117thereby preventing the outer wall116from splitting or cracking along a line proximate to the bottom of the recess114. The enlarged cavity112is formed distally from the end edge128of the end portion118of the gypsum board14, the enlarged cavity112extending laterally across the end portion118of the gypsum board14a predetermined and parallel distance from the end edge128. Sliding the tool bit20laterally across the end portion118via the side edges126such that the rotating tool bit20initially engages a first side edge126of the gypsum board14and proceeds laterally through the end portion118of the gypsum board14until exiting the end portion118via an opposite second side edge126, prevents the flared end110of the tool bit20from boring a relatively large “starter hole” from the end edge128into the end portion118a depth equal to the length of the tool bit20. Extending the enlarged cavity112laterally across the end portion118of the gypsum board14without including a starter hole, promotes the bending and tapering of the end portion118from the enlarged cavity112to the end edge128of the gypsum board14thereby configuring an uniform tapered end portion118. Avoiding a starter hole, reduces the possibility of the gypsum board14initially bending somewhere along the longitudinal axis of the starter hole. Initially bending the end portion118at a location other than the enlarged cavity112, would result in a non-uniform bending and inconsistent taper of the end portion118of the gypsum board14that could cause a humped or crowned seam when adjacent, inconsistent tapered end portions118of adjacent gypsum boards14are taped and covered with joint compound.

A myriad of tool bit end110configurations can be utilized when forming the enlarged cavity112. The preferred configuration is a substantially flared or bell shaped design that includes a horizontal dimension (corresponding to the horizontal movement of outer wall116depicted inFIGS. 23–26) of substantially about one-half the thickness of the gypsum board. The vertical dimension of the cavity112need only be about one-half the horizontal dimension. The depth of the recess114corresponds to the axial length of the bit20which is generally between two and three inches.

To maintain the position of the outer wall116after being bent to a tapered position, a securing tape122is disposed at a plurality of locations upon end edges128of the outer walls116and117of all the tapered end portions118of the gypsum boards14, thereby facilitating the fastening of the tapered end portion118of the gypsum board14onto the support structure120.

The foregoing description is for purposes of illustration only and is not intended to limit the scope of protection accorded this invention. The scope of protection is to be measured by the following claims, which should be interpreted as broadly as the inventive contribution permits.