Patent GB-595919-A (GB)
Title: Improvements in apparatus for finishing the edges of such articles as bi-metallic clutch and brake elements
IPC: B23D67/00
Filed: 1945-07-09
Abstract: 595,919. Reciprocatory filing- machines. BURGESS, A. F. (Wellman Co., S. K.). July 9, 1945, No. 17451. [Class 83 (iii)] [Also in Group XXIII] The edges of articles, particularly brake and clutch elements having facings of sintered metal which, when applied, have overhanging or sharp edges which tend to break away, are smoothed or rounded by passing the articles through a passage between peripherally arranged abrasive members. As shown, the abrasive members or shoes 67 of the unit 13, are circularly arranged in spaced relationship to operate on a work piece 1 of annular form with radially projecting lugs which lie in the spaces between the shoes 67. The abrasive face of each of the shoes is formed by gluing a strip of abrasive cloth 68 thereto, or a file-like face may be attached. The shoes are carried between upper and lower rings 61, 62 which are welded to a spacing sleeve 63 and are carried in radial slots 73, the upper slots having wells 74 to permit the shoes to be removed. Each shoe is pressed resiliently inwards by screw and spring means 81 so that it rocks about the point 84 as the article is forced downwardly through the passage by a pusher 38 on the rod of a plunger operated by air-pressure. The work piece is received on a plate 101 which is swept by two pivoted arms 108 to eject it over a shoot 110. The inside edges of the article are similarly finished by a unit 16 comprising a circularly arranged series of shoes 154 with external abrasive surfaces, the shoes being oppositely tapered longitudinally so that the gaps between them do not result in parts of the inside edge of the article being untreated. The shoes are mounted similarly to the shoes 67, between upper and lower plates 151, 152, but the resilient fulcrum members 171 are adjusted by a central wedge axially adjusted by screw means 191 which is locked against inadvertent movement by a set screw 193. The unit 16 is moved bodily upwards, through the plate 101 into the passage of the unit 13, by the plunger of an air cylinder, the plunger carrying relatively stationary cam means which engage twists in shafts carrying the arms 108, so that the arms are oscillated during the rise and fall of the unit 16. Fig. 12 shows abrasive shoes 67, 154 in an intermediate phase operating on the outside and inside edges of an annular work piece 1, only one side of which is shown. The work is left, after withdrawal of the shoes 154 on the plate 101 below which is arranged a dustcollecting trough 131 with a discharge 138 connected to suction. Dust from the shoes 67 passes through openings 80, the dust being directed into the trough 131 by a blower ring 121 through which the cylinders operating the pusher 38 and the unit 16 are exhausted. The apparatus is operated pneumatically by opening two spring-closed valves 222, two valves being provided to compel the operator to use both hands for safety reasons. Air is thus admitted to a cylinder which moves forward a spring- returned. rack meshing with a pinion on a valve spindle, the valve being thus turned to admit air to the cylinders of each of the units 13, 16. The valve 222 are then released and the downward movement of the pusher 38 and the upward movement of the unit 16 continue until a valve 209 is opened by a cam 219 hitting a lever 216. This exhausts the rack-operating cylinder and allows the valve to rotate back to the position in which the plungers of the cylinders are fully retracted. Another work piece is then inserted. The top ring 61 has bevelled positioning slots for engaging the radial lugs on the work piece. In a modification, the inside finishing unit 16 is dispensed with, and the work piece is discharged directly from the unit 13 over an inclined shoot. The apparatus may be disposed horizontally instead of vertically, in which case the gravity discharge would render the ejector mechanism unnecessary.