Patent GB-189729410-A (GB)
Title: Improvements in Pneumatic Wheel-centres.
Inventor: EVANS JOHN
Filed: 1897-12-11
Granted: 1898-12-03
Abstract: 29,410. Evans, J., and Healey, R. W. Dee. 11. H u b s.-A pneumatic tube 17 is fitted between the fixed spindle 16 and a non-rotating casing 9 of cylindrical form with coneshaped ends. Larger apertures 3 in the ends of the casing give full play about the spindle. In the form shown, the pneumatic tube is larger at the bottom than the top, but the spindle may be cranked down in the middle to allow of a tube of uniform bore being employed. The spindle is formed of irregular share in cross-section (various examples are described) to prevent the tube which fits it tightly creeping round, and a metal sheath of corresponding section may be attached to, or built into, the pneumatic tube to ensure this. The spokes 7 are fixed to an outer case 2 of corresponding form, the balls 5 of the bearing lying between flanges 4 on this case and annular flanged discs 12 screwed upon the flanges 11 of the casing 9. The discs 12 carry studs 13 which work in slots 23 in cheeks 22 secured to the spindle and having face bearings 22<a> for the discs 12 to work upon. The spindle 16 is squared where it passes through the fork on one side and is provided with a screw 19 and a square nut 20 at the other side, being tightened up by nuts 25. By this arrangement, the hub can rise and fall, cushioned on the tube 17, and can swing to a small extent horizontally on the studs 13 as pivots, stops preventing undue movement. In case of the tube 17 bursting, the casing 9 can be rigidly attached to the cheeks 22 by means of screws 50 entering tapped holes in the discs 12. The tube 17 is inflated through the bore 26 in the spindle 16. Various methods of doing this are described. In the form shown, the flanged tube 31 is connected with the expanded end of the tube 27 by a box nut 33, packing 34 being interposed. The tube 27 passes into the pneumatic tube 17 which is clasped between the nut 29 and a washer 30 by a nut 28. In another form, a flexible pipe leading from the pneumatic tube is passed over a nipple secured to a perforated tubular projection by a tightening snap-catch. The projection is fitted into the spindle, and the joint between it and the nipple is made airtight by a rubber washer. Or the flexible tube may be slipped over a nipple projecting from the spindle and secured by binding it into a groove in the nipple. In all cases the connection is such that it can be readily broken. The inflating-valve consists of a nipple covered by a perforated rubber sheath and held in place by a centrally-bored nut 57 against rubber packing. When inflating the tube 17, the nozzle of the pump is passed into the bore, which is at other times stopped by a plug 55. The rubber sheath expands to allow the pair to pass, but closes on the nipple, so covering its perforations, during the back stroke of the pump piston. Dust-excluclers.-Thin plates 69 over the slots 23 and suitably-flanged overlapping guards are arranged to exclude dust ; or overlapping flanges on the conical ends of the casing 2 and on the discs 12 may be utilized. Lubricating.-The ball bearings may be lubricated through holes 76 covered by spring lids with india-rubber pads, or tubes leading to oil cups with removable caps may be used. Or, again, an oil cylinder may screw down upon a fixed piston with tubular rod acting as a conveying tube. The pins 13 may be lubricated through a hole in the cheek 22 stopped by a plug 90 or fitted with an oil cup and conveying-tube.