GB191208662A - An Improved Machine for Grinding Balls. - Google Patents

Abstract

8662. Greene, A. E. April 12. Balls, shaping and surfacing.-A machine for surfacing spherical objects such as balls comprises a work-holding chuck 56, Fig. 2, the axis 58, 55 of which rotates about a main axis 58, 52 and has its inclination to the main axis continually varied during rotation, the intersection of the two axes being the centre of the spherical object to be abraded. The machine shown in Fig. 5 consists of an intermittently rotated drum 9 carrying four spindles 52 with pinions which are continuously rotated by a spur-wheel 19, each spindle having a yoke 77 in which an electro-magnetic chuck 56 is pivotally mounted at 58. Each chuck 56 is also pivoted at its end 55 to a link 54 which is pivoted in turn to a cam sleeve 46 on the spindle 52. The sleeve coacts with a roller on the drum 9 to rock the chuck about its pivot 58 as it is rotating, and thus present various portions of the ball to the cup grinder 97. The electromagnetic chucks are energized from brushes 61 which contact with segments 60 on the drum, each segment being connected with a chuck. The drum 9 is intermittently rotated onequarter of a revolution and the grinder 97, which is mounted on a slide 11, is advanced and withdrawn by a cam 87. The sequence of operations is as follows. (i) A chuck is energized to take a ball from a feed-shoot 105. (ii) The drum is rotated a quarter of a revolution to bring the ball opposite a grinder, which is then advanced to the work and subsequently withdrawn. (iii) The drum is again rotated a step during which the chuck is deenergized, and a friction surface 100, with which the ball is in contact during this movement, causes the ball to rotate and turn its untreated surface outwards. At the end of this step the chuck is again energized to hold the ball, and a second abrader is advanced to the work and subsequently withdrawn. (iv) The drum 9 rotates a third step, after which the chuck is de-energized and the ball drops into a receptacle 108. Each chuck acts in succession in a similar manner. The balls are fed to the chucks from a hopper 108 whence they are taken one at a time by a wheel 104 which delivers them to a conveyer 107 having slanting blades coacting with a plate 119 to form pockets. When the blades pass away from the plate, the balls roll down the feed-shoot 105. For dealing with balls of wood or ivory, the electro-magnetic chucks are replaced by vacuum chucks in which the pivoted chuck is in communication through ducts in the pivots 58 with a pipe in the spindle. The spindle is rotatably mounted in a ring and communication is made at appropriate times with air ports so as to effect the sequence of operations above described.