July 1, 1916] 



THE INDIA RUBBER WORLD 



527 



Cord Tires and Cord Tire Fabrics. 



MODERN cord tires owe their origin to the thread fabric 

 invented by John T. Palmer and first used in racing tires 

 on bicycles in 1893. That Thomas J. Jeffery was first 

 in the field with a thread fabric tire as claimed by some, cannot 

 be verified, but it is true that fabric bicycle tires were made at 

 Indianapolis by the G. & J. Tire Co. in the early nineties. 



The name "cord" tire originated in England, where the prin- 

 ciple was first applied to the manufacture of automobile tires 

 in 1900. It was known as the Palmer cord to distinguish it from 

 the lighter Palmer cord bicycle tire. The Silvertown cord tire 



Palmes 



was invented and patented by Christian H. Gray and Thomas 

 Sloper of England, and manufactured at Silvertown, England, 

 by the Palmer Cord Tire Co., and in the United States, under 

 license, by The B. F. Goodrich Co. 



THE SILVERTOWN CORD TIRE. 

 In this tire, the cords are built up from units of 24 threads 

 that are separately impregnated with rubber and subjected to 

 uniform tension. They are then cabled and the foregoing opera- 

 tion repeated until cords of the required sizes are produced, 

 which are flattened in a machine specially constructed for the 

 purpose. The two layers of these flattened cords are applied 

 in the following manner: First, a layer of rubber is applied 

 to the core — set in the tire building machine. A series of metal 

 staples, 300 in number, are then placed at spaced distances 

 around the inner edge of the bead ring. The cord is fed from 

 a supply spool to a tension governor which regulates the de- 



SiLVERTowN Cord. 



livery and maintains a reserve supply under uniform tension. 

 A folding device measures off an exact length of cord and folds 

 it into double loops which are seized by automatic fingers and 

 placed diagonally on the core and, at the same time, on the bead 

 staples. At the anchorage or smaller circumference of the tire 

 the cords are arranged on edge, and as they approach the tread 

 or larger circumference of the tire each cord is given a quarter 

 twist so that it lies flat on that part of the core corresponding 

 to the tread. When one complete layer is placed around the 

 core, a layer of rubber follows, over which a second layer of 

 cord is applied in the same manner as the first but at the reverse 

 angle. Then another layer of rubber follows which completes 

 the carcass. 



THE DICKINSON CORD TIRE. 

 The principles embodied in this tire and the machine for con- 



structing the carcass show effort on the part of the inventor to 

 improve the art and practice of cord tire making. The separate 

 strands of which the cords are composed are thoroughly im- 

 pregnated with rubber which penetrates to the finest fiber. Thus 

 a bond is created, not only between the cords but between the 

 individual fibers of which the cord is composed, thereby pre- 

 venting friction within the cord itself or between the separate 

 cords. These are formed originally in flat section, the initial 

 strength being retained ; and the possibility of breaking the yam 

 fibers by application of pressure is obviated. 



The cords are laid to a true helix under uniform tension on 

 the tire core by a new automatic machine, in such a manner 

 that the full area represented by the variable circumference be- 



Dickinson's Cord. 



tween the bead and tread is covered without packing, twisting, 

 or distorting the cords. The cord loops are firmly anchored 

 around the annular bead rings which are subsequently built into 

 the carcass, thereby retaining the relative positions of the cords- 

 throughout the process of building and vulcanizing the tire. 

 This method of construction permits curing the tire on the 

 core, and therefore no distortion in the carcass occurs through 

 the necessity of removing the core before a permanent bond is 

 created between all the cords by vulcanization. 

 DEES CORD TIRE. 

 The Dees cord tire is built up on another new type of cord 

 laying machine. The tire core is revolved and the rubberized 

 threads are wound around it by a rotary winder in the form 

 of a reel that carries the four thread bobbins and also the rub- 

 ber solutioning cylinders. The threads are first impregnated with 



Dees Cord 



rubber solution and then passed through rubber dough tmder 

 pressure. They are then wound under tension around the core 

 from one set of bobbins diagonally in one direction while the 

 other ply from the other set of bobbins is wrapped diagonally 



