Patent Application
20200331112
The present disclosure generally relates to cut-off tools, and more particularly, to an accessory cover assembly for a cut-off tool providing a selectively adjustable depth stop, perpendicular cutting guide, and stabilization support.
Cut-off tools are hand-held power tools suitable for cutting light materials such as sheet metal and thin plate. Typically, these tools have a grip sized for a user to hold in one hand when operating the tool. Cut-off tools rotate a cutting wheel about an axis generally aligned with a centerline of a motor housed in the grip. The size and shape of the tool, as well as, the orientation of the cutting wheel facilitate using the tool in tight work spaces that would be difficult to reach with many most two-handed tools. In addition, cut-off tools are well-suited for cutting protruding material flush with the surface from which it protrudes. Cut-off tools may have a fully exposed cutting wheel to improve the visibility of the wheel. Although visibility of a cutting wheel improves cutting precision, an exposed wheel tends to propel debris and sparks from the surface being cut. The debris and sparks may damage surfaces they contact. Accessory cutting wheel covers are sometimes used to enclose a portion of the wheel to block debris and sparks from being thrown beyond the cover. Frequently, the covers enclose about half of the circumference of the wheel to limit the directions in which the debris and sparks travel. One downside of using a cover is that the cover may obscure the cutting wheel and the surface of the material being cut. The lack of visibility can result in cutting too deep, potentially damaging objects below the material, or cutting oblique to the surface of the material, potentially resulting in rework or repair. Thus, a need exists for a cover that limits cutting depth and facilitates making cuts normal or perpendicular to the surface being cut. Moreover, using cut-off tools requires a steady hand to make a straight cut. Therefore, a need also exists for providing the tool with a stabilizing support to facilitate making good cuts.
In one aspect, the present disclosure includes a cover assembly for use on a cut-off tool. The tool has a housing and a motor having a rotor mounted inside the housing. The motor is selectively operable to rotate the rotor about a centerline. Further, the cut-off tool has an output shaft adapted for fastening a cutting wheel to the shaft. The output shaft is operatively connected to the rotor, so the output shaft turns about an axis that is generally aligned with the centerline of the rotor. The cover assembly comprises a semi-annular cover sized and shaped for receiving the cutting wheel when the cutting wheel is fastened to the output shaft. The cover has a collar sized for receiving a portion of the tool surrounding the output shaft. The collar is releasably fastenable to the portion of the tool to attach the cover to the tool. The tool also includes a foot having an elongated planar sole pivotally attached to the cover for pivotal movement relative to the cut-off tool when the collar is fastened to the portion of the tool. The foot is selectively pivotable with respect to the cover to adjust a distance that the cutting wheel extends from the sole. The cover includes a clamp positioned for clamping the foot to the cover when the distance the cutting wheel extends from the sole corresponds to a desired maximum cutting depth.
In another aspect, the disclosure includes a cut-off tool, comprising a housing and a motor having a rotor mounted inside the housing. The motor is selectively operable to rotate the rotor about a centerline. The tool includes an output shaft adapted for fastening a cutting wheel to the shaft. The output shaft is operatively connected to the rotor, so the output shaft turns about an axis when the motor operates. In addition, the tool comprises a cover assembly, including a semi-annular cover sized and shaped for receiving the cutting wheel when the cutting wheel is fastened to the output shaft. The cover has a collar sized for receiving a portion of the housing surrounding the output shaft. The collar is releasably fastenable to the portion of the housing to attach the cover to the housing. Further, the cover assembly includes a foot having an elongated planar sole pivotally attached to the cover for pivotal movement relative to the cut-off tool when the collar is fastened to the portion of the housing. The foot is selectively pivotable with respect to the cover to adjust a distance that the cutting wheel extends from the sole.
Other aspects of the disclosure will be apparent in view of the following description and claims.
Corresponding reference characters indicate corresponding parts throughout the drawings.
Referring to
Although the output shaft 38 pivots upward or downward, the shaft rotates about an axis 44 generally aligned with the centerline 30 of the rotor 28. A lock sleeve 46 is provided to maintain the output shaft 38 in a selected orientation. To articulate or flex the joint 42 the user moves the lock sleeve 46 forward against a biasing force of a retainer spring (not shown), disengaging a locking mechanism so the joint is free to articulate up or down to a desired orientation. The lock sleeve 46 is biased rearward toward its locked position by the retainer spring. Once the output shaft 38 is in the selected orientation, the user releases the lock sleeve 46, allowing it to move rearward to engage the locking mechanism and hold the joint 42 and output shaft in their selected orientations. The power shaft 40 transmits torque between the rotor 28 and the output shaft 38 regardless of the orientation of the joint 42 relative to the housing 22. Bushings and bearings (not shown) are provided inside the joint 42 to allow the output shaft 38 and power shaft 40 to spin freely inside the joint while the joint remains stationary in its selected orientation. A cutting wheel 48 is fastened to the output shaft 38 by a bolt 50 and a pair of washers 52 so the cutting wheel rotates about the output shaft axis 44. The tool 20 may have a lever stop 54 to prevent the lever 34 from inadvertently actuating the valve 36. Further, the tool 20 may include a regulator knob (not shown) for controlling a speed at which the rotor 28 turns about the centerline 30 and the output shaft 38 turns about its axis 44. The tool 20 may also include other features such as a reverse selector (not shown) for selectively reversing a direction in which the rotor 28 and the output shaft 38 rotate inside the housing 22. As these features and the operation of the tool 20 described above are conventional and well understood by those skilled in the art, they will not be described in further detail.
As illustrated in
As illustrated in
Shaped gussets 104 extend between the tongue 98 and the sole 90 and the tab 92 positioned on the same side of the sole as the tongue. The gussets 104 stiffen the sole 90 to prevent bending and strengthen the connections between the sole and the tongue 98 and between the sole and tab 92. The gusset 104 and sole 90 include a shaped notch 106 to provide clearance for the joint 42 when the cover 62 and foot 64 are brought close to one other. Although the foot may be made from other materials without departing from the scope of this description, the illustrated foot 64 is machined from cast aluminum. Visible surfaces of the foot 64 may be grit blasted to improve the appearance of the foot.
To install the accessory adjustable cover assembly 60, the cutting wheel 48 is removed from the tool 20. The machine screw 84 extending through the ears 80a, 80b of the collar 78 is loosened to open the gap 82 and enable the collar to slide over the joint 42. Once the collar 78 is in position on the joint 42, the machine screw 84 is tightened to hold the cover assembly 60 on the tool 20. Should the user desire to change the orientation of the cover assembly 60 relative to the throttle lever 34 and grip 24, the machine screw 84 is loosened, allowing the collar 78 to rotate relative to the joint 42 before retightening the machine screw. Once the cover assembly 60 is attached to the tool, the cutting wheel 48 may be installed by first positioning a washer 52 on the output shaft 38, followed by the cutting wheel and a second washer, before fastening the bolt 50 to the output shaft to hold the cutting wheel in place. The cutting wheel 48 may be centered in the broad slot 96 in the sole 90 by loosening the machine screw 84 and repositioning the assembly 60 before retightening the machine screw to hold the cover assembly in position. With the cover assembly 60 position adjusted as described above, the wing bolt 102 may be loosened to adjust the distance D the cutting wheel 48 protrudes below the sole 90. When the cover 62 and foot 64 are oriented to provide the desired distance D, the wing bolt 102 is retightened to provide a stop to ensure the maximum cutting depth setting. As will be apparent to those skilled in the art, the illustrated articulating cut-off tool 20 is well suited for use with the cover assembly 60 because the joint 42 can be angled to provide optimal clearances and angles for the tool 20.
When the cutting wheel 48 is rotating in its typical forward direction, the debris and sparks travel away from the cutting wheel toward the pivot axis defined by the screws 94 holding the tabs 92 to the cover 62. Because the distance between the sole 90 and cover 62 remains constant at the end of the sole having the tabs 92, the cover consistently contains the debris and sparks when the cutting wheel 48 rotates clockwise as shown in
Having described the drawings in detail, it will be apparent that modifications and variations may be made without departing from the scope of the subject matter defined in the appended claims.
As various changes could be, made in the above constructions, products, and methods without departing from the scope of the invention, it is intended that all matter contained in the above description and shown in the accompanying drawings shall be interpreted as illustrative and not in a limiting sense.
When introducing elements, the articles “a”, “an”, “the”, and “said” are intended to mean that there are one or more of the elements. The terms “comprising”, “including”, and “having” are intended to be inclusive and mean that there may be additional elements other than the listed elements.
