Patent GB-476905-A (GB)
Title: Abrading apparatus
IPC: B24C3/24
Filed: 1936-09-23
Abstract: 476,905. Sand-blast. AMERICAN FOUNDRY EQUIPMENT CO. Sept. 23, 1936, Nos. 25877 and 25878. Convention dates, Sept. 26, 1935 and Dec. 4, 1935. [Class 60] Apparatus for cleaning castings, forgings, and other metallic articles comprises an abrasive-throwing wheel designed to throw a controlled stream of abrasive over a confined sector of less than 180‹ to form an impingement pattern along which the articles or one or more tables carrying the articles are moved and simultaneously rotated in such a manner that points on the articles cross the pattern laterally in alternate directions as they move along it. In one form of apparatus, Figs. 4 and 5, the articles to be treated are carried by turntables 70, supported by arms 75 extending radially from a spindle 72 adapted to be rotated by a motor through speed reducing gearing. Each turntable is mounted on a shaft 76 carrying a pulley 80 coupled by a belt 81 with a second pulley 82. For about one half of its rotation about the spindle 72 each turntable is given a rotary motion about its shaft 76 by means of an arcuate traction belt 90 which engages the outer portion of the belt 81 where it passes round the pulley 82. During the other half of the rotation about the spindle 72 the turntables are carried past an open extension 18 of the housing 15 to enable articles to be removed from or placed on the tables. Within the housing 15 each turntable passes beneath an abrasive-throwing wheel 30, which form an abrasive stream S. The used abrasive is collected by a hopper 17 and fed by a screwfeeder 51 into a hopper 52 communicating with a bucket lift conveyer 65 by which it is returned to the hopper 40. In a modified form of apparatus, Figs. 10 and 13, the abrasivethrowing wheel mounted within a hinged semicircular casing 125 is supplied with abrasive from a hopper 150 under the control of a pivoted closure 153 controlled by a lever 155 from a handle 159 associated with a scale plate 158. As before, spent abrasive is returned by a screw-feeder to the buckets 166 of a conveyer. The tables 187 carrying the articles to be treated are supported from a driven shaft 180 by means of radial arms 186 each supporting a pair of tables. Each arm is formed at its outer end with two bearings 188, each supporting a pivot pin 189 carrying an arm 190 which at its other end has a pivot portion 193 supporting a table 187 through a pivot pin 194 and a ball thrust bearing 197 and a drum 196. The lower end of the pivot 193 carries a roller 206 adapted to engage within a track 208 and so determine the actual path of the table within the housing 121. While moving beneath the stream of abrasive each table is given a rotary motion about its pivot 193 by means of a belt 241 driven from a motor 250 and engaging the drum 196. In a further modification, Fig. 15, the driven shaft 300 carries only three radial arms 302 each supporting two pivoted arms 303 carrying drums 306 and tables 304 which are guided by rollers engaging within a substantially square track 308. Two abrasive projecting wheels 314 and 315 are provided at opposite sides of the housing and are inclined to the path of the track 308 at those sides. During their passage through the two streams of abrasive the tables are rotated by means of driven belts 311, 312 engaging the drums 306. Articles may be placed on the table at one side i of the track for treatment by one abrasive stream and as they pass the other side m may be inverted for treatment by the other stream. For treating articles such as ring gears when it is desirable to provide a separate table for each article, the form of apparatus shown in Fig. 18 may be used. In this form a relatively large number of tables 416 are supported on spindles 415 each mounted on an endless belt 414 driven by a drum 411. At one side of the housing 401 the tables pass beneath an abrasive-throwing wheel 30 and at the other side pass a loading and unloading opening 450 protected by baffles. When moving along the wheel side of the housing, the tables are rotated by means of an endless belt 431, the upper run of which engages the drums below the tables. Baffles 456, 457 and 458 protect the belts from the abrasive stream.