PNEUMATIC WHEEL SANDER

Abstract: A pneumatic wheel sander comprising a wheel (1) having an annular well (2) between two spaced apart radial flanges (3) to give a substantially H-shaped cross-section. A tyre (9) carrying two annular beads (10) configured to fit into two recesses (11) in the flanges (3) and held therein by retaining members (13) is maintained under air pressure via an air inlet valve (7) in one flange (3) and an air passage (8), with a fitting (5) for adaption to a driving source, being located in the other flange (3).

Description: "PNEUMATIC WHEEL SANDER" This invention relates to a pneumatic wheel sander, more particularly to a sander in which the tyre of the wheel is held in position by a simple and effective means. 5. BACKGROUND OF THE INVENTION Pneumatic wheel sanders are well known and with these the bead of the tyre is held in position by being clamped between a removable rim or flange which is bolted or otherwise secured to the body of the wheel. Thus in order to produce such a wheel sander, 10. the body of the wheel has to be formed, and then a pair of replaceable flanges have to be produced which in turn have to be bolted to the body of the wheel. Patent specification DE 3,431 ,670 discloses a grinding wheel in the form of a cylinder with an inflatable rubber wall. Annular grooves is. are provided in end flanges, the edges of the rubber wall being folded into the annular grooves and retained by end caps with skirts which fit into the grooves, the caps being held in position by a through bolt. U.S. Patent 3,496,685 has an inflatable toroidal body mounted on a 20. central hub, and a pair of stiff flanking discs on the hub to support the sides of the toroidal body. U.S. Patent 3,848,374 is a drum sander having a cylindrical base with a tubular inflatable jacket surrounding the cylindrical base, the jacket comprising radially folded bellows so that it expands to 25. engage the base and to engage a sleeve carrying a cylindrical sanding member. Thus it is an object of this invention to provide a pneumatic wheel sander in which the tyre is retained in position in a simple and effective manner. It is a further object of this invention to provide a pneumatic wheel sander wherein the tyre is retained without the use of any clamping rings or flanges which have to be removed and replaced on the body of. the wheel. 5. BRIEF STATEMENT OF THE INVENTION Thus there is provided according to the invention a pneumatic wheel sander, the body of the wheel having a central well, a circular flange integral with the wheel at each side of the wheel, each flange having a recess to receive the edge of the tyre, and a 10. retaining ring situated in each recess adjacent the outside of the tyre to retain the tyre in position. BRIEF DESCRIPTION OF THE DRAWING In order to more fully describe the invention reference will now be made to the accompanying drawing which is a cross-section of one 15 . embodiment of the invention. DESCRIPTION OF THE PREFERRED EMBODIMENT As shown in the drawing the wheel 1 which can be of cast or moulded aluminium or other suitable metal or plastic is provided with a well 2 and two flanges 3, each flange being dished, in one 20. flange dish there being provided a threaded opening 4 to receive a fitting 5 which is adapted to suit various machines onto which the wheel may be fitted. The threaded opening 4 is provided with a left-hand or right-hand thread 6 so that fitting 5 would not unscrew during use of the 25. wheel, when mounted on clockwise or counter-clockwise turning shafts. The other dished opening in the opposite flange is provided with an air inlet valve 7 which connects to an axial and radial passage 8 opening into the well 2 so that the tyre 9 may be inflated. The air inlet valve may also be positioned in the wall of the recess if so desired. The tyre 9 is provided with a peripheral bead or flange 10 on each side, this engaging in a recess 11 formed in the outer edge of the 5. flange. The recess 11 is formed with a re-entrant portion 12 to receive the bead, and after the tyre is inserted a retaining member 13 is inserted in the recess adjacent the outer edge of the bead. The bead is internally facing and has an edge 14 to engage lip 15 in the re-entrant portion 12 of recess 11. ιo. The retaining member 13 can be an "0" ring of rubber or rubberlike compound or can be a circular endless coil spring, steel circlip, steel or metal wire, a plastic coated wire joined as by twisting the ends together. Upon inflation of the wheel, the pressure in the well 2 causes the is. tyre to be inflated with the bead being pulled against the edge of the re-entrant portion and the "0" ring so forming an effective seal to prevent the escape of air. Due to the shape of the tyre, upon inflation the beads would tend to move toward each other and thus into the recess, thus providing 20. the sealing required. The ring 13 assists in this sealing, but particularly retains the bead in position during assembly and inflation. While the invention has been shown as applied to a wheel having a diameter greater than its width, the invention can also be applied to 25. sanding wheels of much greater length, that is having a length two or three times the diameter of the wheel or any combination of diameter and length. Also while the invention has disclosed a particular formation of bead and recess, it is to be realized that the bead and recess may 30. be of other shapes, and also the angle in which the edge of the tyre engages the bead may vary, and for example with wheels of greater width, the angle of entry can be increased or decreased with the tyre edge thus bending through a greater or lesser angle and also it may not be necessary to have a particular bead engaging in a recess, but that the tyre can be retained merely by the sealing ring, particularly when the angle has been increased. Although various forms of the invention have been described in some detail it is to be realized that the invention is not to be limited thereto but can include various modifications falling within the spirit and scope of the invention.

Claims: THE CLAIMS DEFINING THE INVENTION ARE AS FOLLOWS: 1. A pneumatic wheel sander, said sander comprising a central body having a pair of spaced flanges defining therebetween a central well, an annular recess on the outer portion of each flange, a cylindrical tyre having side walls, a bead on each side wall 5. received in a respective recess, and a retaining ring in each said recess adjacent the outside of the respective bead to retain each said bead in its respective recess, and means to inflate the tyre. 2. A pneumatic wheel sander as defined in claim 1, wherein each annular recess is formed in its respective flange on the side opposite said well, each said recess having a re-entrant portion extending toward said well, said retaining ring positioning said 5. bead in said re-entrant portion. 3. A pneumatic wheel sander as defined in claim 2, wherein said bead is formed on the inside surface of the respective side wall, said bead having an edge to engage a lip of the re-entrant portion, whereby inflation of the tyre causes the edge to sealingly 5. engage the said lip. 4. A pneumatic wheel sander as defined in claim 2, wherein said retaining ring is selected from an "0" ring, an endless coil spring, steel or metal wire or plastic coated wire. 5. A pneumatic wheel sander substantially as hereinbefore described with reference to and as illustrated in the accompanying drawing.

Inventors: SMITH ROBERT KEITH, SMITH, ROBERT, KEITH
Applicants: SMITH ROBERT KEITH, SMITH, ROBERT, KEITH
Application year: 1987
Main classification: B24D9
IPC codes: B24D9, B24D13