Patent GB-1010178-A (GB)
Title: Apparatus for surfacing glass
IPC: B24B7/24
Filed: 1962-08-07
Abstract: 1,010,178. Surfacing glass. LIBBEYOWENS-FORD GLASS CO. Aug. 7, 1962 [Sept. 14, 1961], No. 30158/62. Heading B3D. Apparatus for surfacing a glass sheet 20, Fig. 1, moving along a substantially horizontal path comprises a generally rectangular surfacing platen 40 extending transversely across the path, means for applying a translatory motion to said platen including a pair of spaced driving spindles 48, Fig. 6, a bearing assembly 132, 133 carried by the platen at opposite ends thereof for receiving the spindles, and means operatively associated with the bearing assemblies for mounting said platen to the spindles to enable the platen to rock in a vertical plane normal to the direction of movement of the sheet about an axis extending transversely of the platen and parallel to the direction of movement of the glass. As described, the apparatus has two surfacing stations 22, Fig. 1, each of which has upper and lower platens 40, 40a for surfacing the upper and lower surfaces of the glass. The upper parts of the surfacing stations are carried by a framework 24 and each part consists of a pair of head assemblies 27, Fig. 4, each of which is in the form of a cylinder 28 in which a sleeve 41 is slidable. A spindle 48 is carried by bearings 45, 46 within the sleeve for  axial movement therewith and at its upper end has a projection engaging a keyway in a member 33 mounted in bearings 34 in the cylinder. The member 33 is formed with a wheel 32 engaged by a worm on a shaft 36 connected by a coupling to one end of a double-ended motor, the other end of which is connected to the shaft and gearing of the other assembly whereby both driving spindles 48, which are connected by eccentric mechanisms 53 to the platen, are driven at the same speed. The sleeves 41, with the spindles 48, are axially movable to raise and lower the platen by rotation of a shaft 69, Fig. 5, by manual or motor means, the shaft being connected by bevel gearing to threaded spindles 64 engaging blocks 62 having extensions 60 which pass through slots 61 in the cylinders 28 and engage recesses 57 formed in the sleeves. Each sleeve is also formed with a rack 78, Fig. 4, engaged by a gear segment 85 joined by an arm to the rod of a pneumatic piston-and-cylinder device 75 mounted on the cylinder, whereby the platen is urged against the surface of the glass. The lower surface polishing stations 23 are similar to the upper stations and each head assembly has a selsyn system for synchronizing the movements of the upper and lower platens which are preferably 180 degrees out of phase. The eccentric mechanisms 53 on the ends of the spindles each consist of two rectangular blocks 107, 108, Fig. 1] which can be offset relative to each other along a slide 110 by screws 111 which pass through slots 112 in the block 108 into threaded holes 113 in the block 107 to effect the desired eccentricity between the spindle 48 and a spindle 109. Weights 116 are provided to balance the centrifugal force of the platen. Each spindle 109 is received in a sleeve 176 which is releasably secured to the plate 108 by a split clamp 114 and has bearings 178, 179 in a housing 160. The housing 160 is formed with a pair of trunnions 161 which have their axes transverse to the length of the platen and are received in bushings 162 secured to a trunnion block 148, Fig. 9, consisting of two L- shaped members joined together. Each trunnion block is located in a bearing well 134 consisting of walls upstanding from the platen. One trunnion block of each platen is secured in its well 133, Fig. 8, by two sets of screws 139, 154 which press clamping plates 153 against the trunnion block. The other trunnion block 148 is located in the other bearing well 132 which has two clamping plates 138, 153, Fig. 9, which can be urged against the block by screws 139, 154 and a wedge member 145 which can be moved by screws 144 relative to a fixed wedge 146 to adjust the spacing between the trunnion blocks. Pads 149, 156, 166 and 167 of vibration dampening material are disposed between the trunnion blocks and the clamping plates or walls of the well. Lubricant is contained in reservoirs 172, 175, Fig. 11, for the trunnions and bearings and dirt is excluded from the bearings by a seal 185 and guard 186. In operation, the distance between the bearing sleeves 176 of a platen is established by a template or gauge having plugs of the same diameter as the spindles 109. The trunnion block of the bearing well 133 is clamped first and then the other block is adjusted to the spacing determined by the gauge. After setting, the platen is mounted on the spindles 109 and secured thereto by the screws 115 in the clamps 114. The working face of a platen consists of a hollow pan-like member 190 having a felt or like pad 191, Fig. 13. A ribbed superstructure 192 is welded to the upper surface of the member and a series of inverted channels 193 extend transversely of the platen, are closed by walls 194 at their outer ends and are provided at their ends with threaded bores 196, some of which are closed by plugs and some of which are connected by pipes 198 to a source of polishing slurry. The pan-like member 190 is formed with holes 200 which connect the channels to grooves 199 extending longitudinally of the platen. The pan-like member is releasably secured to the platen by toggle devices 202, Fig. 11, and is located relative thereto by a bar on the member engaging a groove in the platen.