Patent GB-1517502-A (GB)
Title: Manufacture of balls
IPC: A63B45/00
Filed: 1974-06-13
Abstract: 1517502 Applying covers to ball cores DUNLOP Ltd 10 June 1975 [13 June 1974] 26341/74 Heading A6D A ball core 100 may be covered using the apparatus shown in Figures 1, 2 and 8 (and Fig. 3 to 7, 9 and 10 not shown) in which the core is placed in the throughway 76 of a loading plate 8 to locate against a ledge 94. A felt covering piece 101 having one side coated with an adhesive is then positioned in a slot 81 above the throughway 76 (Fig. 8) in the top surface of the loading plate 8 with the adhesive coated side facing the base of the apparatus. A second felt piece 102 also having one side coated with an adhesive is then located in a further slot 82 above a throughway 15, with the adhesive coated side facing towards the top of the apparatus. The loading plate 8 is rotated by means of a handle 93 until the throughway 76 lies between enclosure members 1 and 2 (Figs. 2 and 9). The space defined by the enclosure members 1 and 2 and the throughway 76 is then partially evacuated (to 24 inches of mercury) causing the core to expand. A piston 40b is moved upwards (Fig. 3) to push the core 100 from the throughway 76 against the adhesive coated surface of the felt cover piece 101 and into a locating member 9 in the upper enclosure member 1 causing the cover piece 101 to be wrapped around the core and an upper plunger means 10 to be displaced. Displacement of plunger means 10 causes consolidating members 52 and 53 of a gripping means to engage the ball core to grip it and to assist in wrapping the cover piece 101 around the core. The piston 40b is then withdrawn (Fig. 4) into the lower enclosure member 2. The loading plate 8 is then rotated through 120 (Fig. 10) so that throughway 15 lies between the enclosure members 1 and 2 (Fig. 5). The plunger means 10 is then moved down (Fig. 6) causing the consolidating members 52, 53 to release their grip on the ball core which is displaced to contact the adhesive coated surface of the second covering piece 102 and pass into the locating member 12 of enclosure member 2 where the second covering piece is wrapped around the ball core in a manner similar to that described above. The covering pieces are of such a size and shape that a gap exists between their edges when they are located on the expanded core. Upon releasing the partial vacuum from enclosure members 1 and 2, the ball core contracts and the edges of the covering pieces, which have been previously coated with adhesive abut and adhere to each other. The covered ball core is displayed by piston 40b into throughway 15 and is subsequently removed from the apparatus by rotating the loading plate to a position where the throughway 15 is accessible. A further example of ball covering apparatus (Fig. 11, not shown) utilising a rotatable loading plate (150) with throughways and enclosure members (153) and (154) for forming a vacuum chamber is described and functions in a similar manner to the apparatus shown in Figure 1. It may be utilised in a machine (Fig. 22 not shown) for automatically applying felt covering to tennis balls in which ball cores are fed from a hopper (223) and felts are fed from magazines (220) and (221) to a plurality of ball covering apparatuses (201) to (209). Means may be provided to sense the size and shape of the ball core as it is subjected to the partial vacuum and to control the vacuum and the forces exerted by the plunger piston arrangements to limit the deformation of the ball core.