Cross Reference To Related Application

This application claims the benefit of U.S. Provisional Patent Application No. 61/177914, filed May 13, 2009 and U.S. Provisional Patent Application No. 61/322019, filed April 8, 2010, the disclosure of which is incorporated by reference herein in its entirety.

Background

The present invention is directed to a backing plate for a buffing pad and, more particularly, to a backing plate for a two-sided buffing pad which allows the buffing pad to be more easily and quickly released from and reattached to a power buffer. Buffing pads for use in high speed polishing of automobiles and the like may be one-sided or two-sided. A one-sided buffing pad is typically circular and comprises a buffing medium (e.g., foam, wool, etc.) attached to one face of a rigid backing plate which is attached by a central hub to the drive shaft or spindle of a motor for a power buffer. The buffing medium may be permanently attached to the backing plate or releasably attached thereto in order to allow for replacement without disposing of the backing plate. A two-sided buffing pad includes buffing medium attached to each face of a rigid backing plate. The plate includes a hub for releasably attaching the buffing pad to the drive shaft or spindle of the buffing motor. The pad may be attached to the drive shaft or spindle of the motor from either side of the buffing pad, thereby allowing the pad to be reversed after one side has been used.

A backing plate used with a quick release buffing pad assembly and, more particularly, used with a two-sided buffing pad, is shown, for example, in U.S. Patent No. 6,349,446 to Krause et al., the entire disclosure of which is incorporated herein by reference. The backing plate includes a central opening that receives a connector having a hexagonally shaped opening that is intended to be secured to the complimentary hexagonally shaped head of a quick connector such as that also shown in U.S. Patent No. 6,349,446. Summary of the Invention

There is provided a backing plate for a buffing pad that is comprised of a substantially circular disc having first and second surfaces that are adapted to be connected to the nonworking faces of first and, optionally, second buffing media to form a single-sided or two-sided buffing pad. The disc has a central hub with an axial opening therein that is adapted to connect the backing plate to a shaft of a power buffer. The opening is formed of a plurality of straight walls, with the ends of adjacent walls being spaced apart from each other and not directly connected to each other. This arrangement advantageously prevents the opening from deforming so that it can be easily connected to and removed from a quick connector. Preferably, the axial opening comprises six straight walls arranged in a substantially regular hexagonal pattern with a substantially circular recess formed between the ends of adjacent walls. The straight walls forming the axial opening of the central hub may have a groove that circumscribes the opening or the walls may include a dimple.

Brief Description of the Drawings

For the purpose of illustrating the invention, there is shown in the accompanying drawings one form which is presently preferred, it being understood that the invention is not intended to be limited to the precise arrangements and instrumentalities shown.

Figure 1 is a top plan view of one embodiment of a backing plate for a buffing pad according to the invention;

Figure 2 is an enlarged view of the center hub of the backing plate of Figure 1; Figure 3 is a view similar to Figure 2 but showing the backing plate mounted on a connector for connection to a shaft of a power buffer;

Figure 4 is a perspective view showing the backing plate being connected to a connector;

Figure 5 is an enlarged perspective view similar to Figure 4 but showing the backing plate connected to the connector; and Figure 6 is a perspective view similar to Figure 4 but showing an alternative embodiment of the backing plate. Detailed Description

Referring now to the several drawings in detail wherein like reference numerals have been used throughout the various figures to designate like elements, there is shown in Figure 1 a backing plate 10. Backing plate 10 is adapted for use with a buffing pad such as a single-sided or two-sided buffing pad (not shown separately in the drawings). As described below, backing plate 10 is particularly suited for use with a quick connector (sometimes called a quick release connector) adapted to connect a buffing pad to a power buffer.

The backing plate 10 is comprised of a substantially circular disc 12 having a first surface 14 which is adapted to be connected to the nonworking face of a first buffing medium such as foam, wool or the like (not shown separately in the drawings). The opposite side of disc 12 has a second surface 16 which is adapted to be connected to the nonworking face of a second buffing medium if a two-sided buffing pad is being used. Disc 12 is a plate-shaped member, generally. It is, of course, possible to utilize the backing plate 10 with a single-sided buffing pad and a quick release connector therefore. In such a case, a buffing medium is secured to only one surface 14 or 16 of the disc 12. Holes or openings 18a, 18b, 18c and 18d in disc 12 help to secure the buffing media to disc 12 by allowing the medium on each surface 14 and 16 to be glued or otherwise attached to each other. In a single-sided buffing pad, a layer of fabric or other material can be attached to the opposite side of disc 12 and glued or otherwise attached to the nonworking surface of the single medium through the openings 18a-d.

Disc 12 includes a central hub 20 which, as shown most clearly in Figures 4 and 5, is thicker than the remaining portions of the disc. The central hub 20 includes an axial opening 22 therein which is adapted to connect the backing plate 10 and the buffing pad which is formed utilizing the backing plate to a shaft or spindle for a power buffer such as a motor-driven rotary buffer. This connection may be made through the use of a quick connector 24 such as shown in Figures 4 and 5.

To prevent movement (e.g., rotation) of the backing plate 12 relative to the quick connector 24, the quick connector includes a hexagonally shaped head 26 and the opening 22 in the hub 20 is also substantially hexagonally shaped. This is, of course, by way of example only. The present invention is not limited thereto. The invention would also function if the head 26 of the quick connector 24 were formed to have three straight sides resembling a triangle or four sides resembling a square. In fact, substantially any number of sides is possible as long as the opening 22 in the hub 20 has a complementary shape.

The substantially hexagonal shaped opening 22 is formed of six straight walls such as shown at 28a to 28f. Advantageously, the ends of the adjacent walls do not directly connect to each other. As can best be seen in Figures 1 and 2, there is a space, slot or indentation 30a which is shown by way of example as a substantially circular recess that is formed between each pair of adjacent walls. Thus, the ends of the adjacent walls are spaced apart from each other and do not directly connect. As shown most clearly in Figures 3 and 5, the corners formed by adjacent walls of the hexagonal head 26 of the quick connector 24 loosely fit within these recesses.

To further prevent movement (e.g., rotation) of the backing plate 12 relative to the quick connector 24, the quick connector may include three displaceable balls 32 (of which only two are shown in Figure 4) that can be received in groove 34 circumscribing the inner surface of the opening 22 as shown in Figure 4. Alternatively, as shown in Figure 6, the balls 32 may be received in corresponding dimples 36 formed in walls 28a to 28f. For convenience of use, a dimple is preferably formed in each wall, although they could be provided only in three walls corresponding to the number and position of the balls. When the quick connector 24 is inserted into the opening 22, the balls 32 can move or be displaced outwardly upon encountering the groove 34 or the dimples 36 so as to be received therein.

To facilitate manufacturing and use, backing plate 10 can be readily formed so as to have symmetrical front and back surfaces. That is, surface 14 and opposite surface 16 of disc 12 are identical to each other in the illustrated drawings, as are both sides of hub 20. Thus, although only portions of the opposite side 16 of disc 12 are shown in Figure 3, it should be understood that the two sides are the same. Of course, surfaces 14 and 16 could be formed so that they are not identical if this does not impair the utility of backing plate 10.

Backing plate 10 is preferably made of plastic. It must be rigid enough to support and adequately buff or polish a surface such as on a motor vehicle but sufficiently flexible to properly allow the buffing medium (typically formed of wool or foam) to bend or flex as needed. Thus, softer more flexible plastics are more desirable for the backing plate. However, while more flexible plastics are preferred for performing the actual buffing operation, the attachment to and detachment from a quick connector can be problematic. As the buffing pad is being used, the softer plastic that also forms the hub of the backing plate can deform from the bending and twisting endured by the buffing pad. This deformation may also deform the hexagonal opening in the hub which can make it difficult to remove the buffing pad from the connector and/or reattach the buffing pad to the connector when it is desired to use the pad again after it has been turned over or cleaned.

Opening 22 formed in hub 20 advantageously allows backing plate 10 to be made from a softer, flexible plastic material because the buffing pad can be easily and quickly released from and reattached to a quick release connector even after it has been used for a period of time.

The present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof and accordingly, reference should be made to the appended claims rather than to the foregoing specification as indicating the scope of the invention.