US20040048549A1

US20040048549A1 - Device for removing an abrasive disk from a sanding pad

Info

Publication number: US20040048549A1
Application number: US10/237,291
Authority: US
Inventors: James Beaudoin; Guy Van Every
Original assignee: Midwest Thermal Spray Inc
Current assignee: Midwest Thermal Spray Inc
Priority date: 2002-09-09
Filing date: 2002-09-09
Publication date: 2004-03-11

Abstract

A device for removing an abrasive disk from a rotary sander of the type having a disk-shaped sanding pad with upper and lower surfaces that are parallel to each other and spaced apart from each other by a predetermined distance. The device includes 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 sanding pad. At least one blade is secured to the frame so that the blade lies in a plane parallel to the guide surfaces and is spaced from the guide surfaces by the predetermined distance corresponding to the thickness of the sanding pad. In use, the sanding pad is moved along the guide rails by a robot so that the upper surface of the sanding pad slides along the guide surfaces. In doing so, the blade engages the sanding pad between its lower surface and its attached abrasive disk thus removing the abrasive disk from the sanding pad.

Description

BACKGROUND OF THE INVENTION

I. Field of the Invention

The present invention relates generally to a device for removing an abrasive disk from a sanding pad.

II. Description of Related Art

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.

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.

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.

SUMMARY OF THE PRESENT INVENTION

The present invention provides a device which overcomes all of the above-mentioned disadvantages of manually removing the abrasive disk from a robotic rotary sander.

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.

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.

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.

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.

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.

BRIEF DESCRIPTION OF THE DRAWING

A 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 INVENTION

With reference first to FIG. 1, a [0019] rotary sander 10 is shown having a disk-shaped sanding pad 12 with an upper surface 14 and a lower surface 16. The upper and lower surfaces 14 and 16, respectively, of the sanding pad 12 lie in parallel planes and are spaced apart from each other by a predetermined distance X, i.e. the thickness of the sanding pad 12.
An [0020] abrasive disk 20 is detachably secured to the lower surface 16 of the sanding pad 12. Any conventional means, such as hook and pile fastener 22 or a pressure sensitive adhesive, may be utilized to secure the abrasive disk 20 to the sanding pad 12.
A [0021] drive shaft 24 extends coaxially outwardly from the upper surface 14 of the sanding pad 12. This drive shaft 24 is rotatably driven by a motor 26 (illustrated only diagrammatically) and the entire rotary sander 10 is manipulated by a robot 28 (illustrated only diagrammatically).
With reference now to FIGS. 2 and 3, a preferred embodiment of a [0022] device 30 for removing the abrasive disk 20 from the sanding pad 12 is shown. The device 30 includes a frame 32 which is mounted in a stationary position in any conventional fashion. Preferably, the frame 32 is made of a rigid material, such as steel.
A pair of [0023] elongated guide rails 34 are secured to the frame 32 so that the guide rails 34 are spaced apart and parallel to each other. Furthermore, each guide rail 34 includes an elongated guide surface 36 in which the guide surface 36 on one guide rail 34 is coplanar with the guide surface 36 on the other guide rail 34. Any conventional means, such as bolts 38, can be used to secure the guide rails 34 to the frame 32.
The [0024] guide surfaces 36 of the guide rails 34 are adapted to abut against the upper surface 14 (FIG. 1) of the sanding pad 12. Each guide rail 34 further includes a side 42 which conforms in shape to an outer periphery 44 (FIG. 1) of the sanding pad 12.
Still referring to FIGS. 2 and 3, at least one and preferably two [0025] blades 50 are secured to the frame 32 so that the blades 50 lie in a plane parallel to the plane of the guide surfaces 36 on the guide rails 34. Furthermore, the blades 50 are spaced from the guide surfaces 36 by the distance X (FIG. 2), i.e. the thickness of the sanding pad 12.
As best shown in FIG. 3, each [0026] blade 50 is preferably tapered at an angle with respect to the longitudinal axis of the guide rails 34. As such, the blades 50 each include a blade edge 52 which angles from an entry end 54 of the guide rails 34 and toward an exit end 56 of the guide rails 34.
Although in the preferred embodiment a pair of [0027] guide blades 50 are secured to the frame 32, alternatively, a single guide blade 50 may be employed.
As best shown in FIG. 3, the [0028] frame 32 also includes a chute 60 extending downwardly from the blades 50 adjacent the exit end 56 of the guide rails 34. This chute 60 is open to a collection bin 62 for collecting the spent abrasive disk after removal from the sanding pad 12.
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 disk 20 becomes worn, the robot 28 moves the sanding disk 12 between the guide rails 34 (only one shown in FIGS. 4 and 5) from the entry end 54 of the guide rails 34 and toward the exit end 56. Furthermore, the robot 28 maintains the upper surface 14 of the sanding pad 12 in sliding contact with the guide surface 36 on the guide rails. Simultaneously, the sides 42 (FIG. 2) of the guide rails 34 effectively center the sanding pad 12 between the guide rails 34.
As the robot moves the [0030] sanding pad 12 along the guide rails 34, the leading edge 52 of the blade 50 engages the sanding pad 12 in between its lower surface 16 and the abrasive disk 20. In doing so, the blade 50 in FIG. 4 initiates the separation of the abrasive disk 20 from the sanding pad 12.
With reference now to FIG. 5, continued movement of the [0031] sanding pad 12 along the guide rails 34 from their entry end 54 and towards their exit end 56 causes the blade 50 to completely remove the abrasive disk 20 from the sanding pad 12. Upon removal, the spent abrasive disk 20 falls through the chute 60 to the collection bin 62. The collection bin 62 is periodically emptied as required.
After removal of the spent [0032] abrasive disk 20 from the sanding pad 12, the robot 28 manipulates the sanding pad 20 to attach a fresh abrasive disk to permit continued operation of the rotary sander 10.
From the foregoing, it can be seen that the [0033] device 30 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 rails 34 in the previously described fashion, the spent abrasive disk 20 can be rapidly removed from the pad 12 thereby minimizing any delay in the abrading operation performed by the robot 28 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]

Claims

I claim:

1. In combination with a rotary sander having a disk-shaped sanding pad with an upper surface and a lower surface, said upper and lower surfaces of said sanding pad lying in parallel planes and spaced apart from each other by a predetermined distance, an abrasive disk detachably secured to said lower surface of said sanding pad, a device for removing the abrasive disk from the lower surface of the sanding pad comprising:

a frame;

a pair of elongated guide rails secured to said frame, each guide rail having an elongated guide surface adapted to abut against the upper surface of the sanding pad on opposite sides thereof; and

at least one blade secured to said frame so that said at least one blade lies in a plane parallel to said guide surfaces and is spaced from said guide surfaces by said predetermined distance.

2. The invention as defined in claim 1 wherein said at least one blade comprises a pair of coplanar and adjacent blades.

3. The invention as defined in claim 1 wherein an edge of said blade is angled with respect to a longitudinal axis of said guide surfaces.

4. The invention as defined in claim 2 wherein an edge of each blade is angled with respect to a longitudinal axis of said guide surfaces.

5. The invention as defined in claim 4 wherein said guide rails have an entry end and an exit end and wherein said edges of said blades angle from said guide rails and towards said exit end of said guide rails.

6. The invention as defined in claim 1 wherein said frame includes a chute adjacent one end of said guide rails.

7. The invention as defined in claim 1 wherein said abrasive disk is secured to said lower surface of said sanding pad by hook and pile fasteners.

8. The invention as defined in claim 1 wherein said abrasive disk is secured to said lower surface of said sanding pad by a pressure sensitive adhesive.

9. The invention as defined in claim 1 wherein each guide rail includes an elongated side, said elongated sides conforming in shape to a side periphery of the sanding pad and spaced apart from each other by a distance substantially the same as a diameter of the sanding pad.