BACKGROUND OF THE INVENTIONI. Field of the Invention[0001]
The present invention relates generally to a device for removing an abrasive disk from a sanding pad.[0002]
II. Description of Related Art[0003]
There are many manufacturing operations in which a robot manipulates a rotary sander to abrade or sand a manufactured item. These rotary items conventionally include a disk-shaped sanding pad having an upper surface and a lower surface. The upper and lower surfaces of the sanding pad lie in parallel planes to each other and are spaced apart by a predetermined distance equal to the thickness of the sanding pad. An abrasive disk is then detachably secured to the lower surface of the sanding pad by any conventional means, such as hook and pile fasteners or pressure sensitive adhesive.[0004]
After prolonged use, the abrasive disk becomes worn and is no longer capable of performing the desired abrasive operation on the workpiece. When this occurs, it is necessary to remove the abrasive disk and replace it with a new abrasive disk.[0005]
Previously, there have been no acceptable devices for automatically removing an abrasive disk from a rotary sander when used in a robotic application. Instead, it has been previously necessary to stop the robot and manually remove and thereafter replace the abrasive disk with a fresh abrasive disk. Such a procedure, however, is disadvantageously labor intensive and, therefore, expensive. Furthermore, since the manual replacement of the abrasive disk is necessarily time consuming, such replacement results in a delay in the manufacturing operation thus increasing the cycle time for the manufacturing operation.[0006]
SUMMARY OF THE PRESENT INVENTIONThe present invention provides a device which overcomes all of the above-mentioned disadvantages of manually removing the abrasive disk from a robotic rotary sander.[0007]
In brief, the device of the present invention is used with a rotary sander of the type having a disk-shaped sanding pad with an upper surface and a lower surface. The upper and lower surfaces of the sanding pad lie in parallel planes that are spaced apart from each other by a predetermined distance. A drive shaft is attached to and extends coaxially outwardly from the upper surface of the sanding pad while an abrasive disk is removably secured to the lower surface of the sanding pad. Any conventional means, such as hook and pile fasteners or pressure sensitive adhesive, is used to secure the abrasive disk to the lower surface of the sanding pad.[0008]
The device of the present invention comprises a frame having a pair of elongated guide rails secured to the frame. Each guide rail has an elongated guide surface adapted to abut against the upper surface of the sanding pad on opposite sides of the pad.[0009]
At least one, and preferably two, blades are also secured to the frame so that the blades lie in a plane parallel to the guide surfaces on the guide rails. Furthermore, the blades are spaced from the guide surfaces on the guide rail by a distance equal to the thickness of the sanding pad.[0010]
In operation, the rotary sander is manipulated by a robot. When the abrasive disk on the sanding pad becomes worn, the robot moves the sanding pad from an entry end of the guide rails and to an exit end of the guide rails while maintaining the upper surface of the sanding pad in contact with the guide surfaces of the guide rails. In doing so, the blade or blades engage in between the lower surface of the sanding pad and the spent abrasive disk thus removing the spent abrasive disk from the sanding pad. A chute formed in the frame adjacent the exit end of the guide rails transports the spent abrasive disk to a collection area for subsequent disposal.[0011]
Since the robot is programmed to slide the sanding pad of the rotary sander through the frame in the above-described fashion, removal of the spent abrasive disk can be rapidly and automatically accomplished.[0012]
BRIEF DESCRIPTION OF THE DRAWINGA better understanding of the present invention will be had upon reference to the following detailed description, when read in conjunction with the accompanying drawing, wherein like reference characters refer to like parts throughout the several views, and in which:[0013]
FIG. 1 is a side diagrammatic view illustrating a robot manipulated rotary sander;[0014]
FIG. 2 is a front view illustrating a preferred embodiment of the present invention;[0015]
FIG. 3 is a top view illustrating the preferred embodiment of the invention;[0016]
FIG. 4 is a side diagrammatic view illustrating the operation of the present invention; and[0017]
FIG. 5 is a side view illustrating the operation of the present invention.[0018]
DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT OF THE PRESENT INVENTIONWith reference first to FIG. 1, a[0019]rotary sander10 is shown having a disk-shaped sanding pad12 with anupper surface14 and alower surface16. The upper andlower surfaces14 and16, respectively, of thesanding pad12 lie in parallel planes and are spaced apart from each other by a predetermined distance X, i.e. the thickness of thesanding pad12.
An[0020]abrasive disk20 is detachably secured to thelower surface16 of thesanding pad12. Any conventional means, such as hook andpile fastener22 or a pressure sensitive adhesive, may be utilized to secure theabrasive disk20 to thesanding pad12.
A[0021]drive shaft24 extends coaxially outwardly from theupper surface14 of thesanding pad12. Thisdrive shaft24 is rotatably driven by a motor26 (illustrated only diagrammatically) and the entirerotary sander10 is manipulated by a robot28 (illustrated only diagrammatically).
With reference now to FIGS. 2 and 3, a preferred embodiment of a[0022]device30 for removing theabrasive disk20 from thesanding pad12 is shown. Thedevice30 includes aframe32 which is mounted in a stationary position in any conventional fashion. Preferably, theframe32 is made of a rigid material, such as steel.
A pair of[0023]elongated guide rails34 are secured to theframe32 so that theguide rails34 are spaced apart and parallel to each other. Furthermore, eachguide rail34 includes anelongated guide surface36 in which theguide surface36 on oneguide rail34 is coplanar with theguide surface36 on theother guide rail34. Any conventional means, such as bolts38, can be used to secure theguide rails34 to theframe32.
The[0024]guide surfaces36 of theguide rails34 are adapted to abut against the upper surface14 (FIG. 1) of thesanding pad12. Eachguide rail34 further includes aside42 which conforms in shape to an outer periphery44 (FIG. 1) of thesanding pad12.
Still referring to FIGS. 2 and 3, at least one and preferably two[0025]blades50 are secured to theframe32 so that theblades50 lie in a plane parallel to the plane of theguide surfaces36 on theguide rails34. Furthermore, theblades50 are spaced from theguide surfaces36 by the distance X (FIG. 2), i.e. the thickness of thesanding pad12.
As best shown in FIG. 3, each[0026]blade50 is preferably tapered at an angle with respect to the longitudinal axis of theguide rails34. As such, theblades50 each include ablade edge52 which angles from anentry end54 of theguide rails34 and toward anexit end56 of theguide rails34.
Although in the preferred embodiment a pair of[0027]guide blades50 are secured to theframe32, alternatively, asingle guide blade50 may be employed.
As best shown in FIG. 3, the[0028]frame32 also includes achute60 extending downwardly from theblades50 adjacent theexit end56 of theguide rails34. Thischute60 is open to acollection bin62 for collecting the spent abrasive disk after removal from thesanding pad12.
With reference now to FIGS. 4 and 5, the operation of the present invention will now be described. In FIG. 4, after the[0029]abrasive disk20 becomes worn, therobot28 moves thesanding disk12 between the guide rails34 (only one shown in FIGS. 4 and 5) from theentry end54 of theguide rails34 and toward theexit end56. Furthermore, therobot28 maintains theupper surface14 of thesanding pad12 in sliding contact with theguide surface36 on the guide rails. Simultaneously, the sides42 (FIG. 2) of theguide rails34 effectively center thesanding pad12 between theguide rails34.
As the robot moves the[0030]sanding pad12 along theguide rails34, the leadingedge52 of theblade50 engages thesanding pad12 in between itslower surface16 and theabrasive disk20. In doing so, theblade50 in FIG. 4 initiates the separation of theabrasive disk20 from thesanding pad12.
With reference now to FIG. 5, continued movement of the[0031]sanding pad12 along the guide rails34 from theirentry end54 and towards their exit end56 causes theblade50 to completely remove theabrasive disk20 from thesanding pad12. Upon removal, the spentabrasive disk20 falls through thechute60 to thecollection bin62. Thecollection bin62 is periodically emptied as required.
After removal of the spent[0032]abrasive disk20 from thesanding pad12, therobot28 manipulates thesanding pad20 to attach a fresh abrasive disk to permit continued operation of therotary sander10.
From the foregoing, it can be seen that the[0033]device30 of the present invention provides a simple and yet effective means for rapidly removing a spent abrasive disk from a rotary sander. Since the robot can be programmed to rapidly move the sanding pad between the guide rails34 in the previously described fashion, the spentabrasive disk20 can be rapidly removed from thepad12 thereby minimizing any delay in the abrading operation performed by therobot28 on the workpiece (not shown).
Having described my invention, however, many modifications thereto will become apparent to those skilled in the art to which it pertains without deviation from the spirit of the invention as defined by the scope of the appended claims.[0034]