THE INDIA RUBBER WORLD 



[AUGU: 



New Machines and Appliances. 



AUTOMATIC CORD TIRE BUILDING MACHINE. 



DVE to the novel method employed in carcass construction, 

 the production capacity of this machine, it is claimed, will 

 average 25 tires per hour. Moreover, the construction 

 permits the saving of materials that are wasted in ordinary cord 

 tire building processes. The specifications for the tire provide for 

 individual cords tensioned to absolute uniformity throughout the 

 process of twisting the separate strands comprising the cabled 

 cord and in the final cabling thereof. The individual strands are 



The Dickinson Tire Builder. 

 thoroughly impregnated with rubber compound that precludes 

 frictional movement within the body of the cords. 



The cords are laid on the core in a series of strips made up 

 of a number of parallel cords formed in cross-section to com- 

 pensate for the variable circumference between the bead and 

 crown, and uniformly covering the full superficial area. The 

 strip-cords are equally distributed on helicoidal lines represent- 

 ing the shortest path between the opposite beads in accord with 

 the angle at which the cords are laid, so that each cord occupies 

 the same relative angular position and bears its full proportion 

 of the stresses and strains of service. 



To form the cord strips that give the progressive increased 

 width from bead to crown, the contour of the cord varies from 

 cylindrical to elliptical, but the displacement is accomplished 

 without rupture of the fibers and the original strength is not 

 impaired. All cords are insulated to prevent frictional contact 

 between them in the separate plies and between the cord plies 

 themselves. To eliminate multiple frictional surfaces two plies 

 only are used, as more plies increase the cross-sectional circum- 

 ference between the first and succeeding plies, amplify frictional 

 action and impose strains on the cords in attempting to meet the 

 constantly changing conditions in the flexing of the tire in 

 service. 



The machine is practically automatic in operation, as the oper- 

 ator has only to do with starting, stopping, supplying the neces- 

 sary material, setting the cores in place and removing them 

 with the finished carcass thereon. The present type machine lays 



fifteen cords simultaneously in units of five cords each at three 

 points over the core, one hundred and twenty degrees apart, the 

 cords being fed from fifteen reels or bobbins through tensioning 

 apparatus, imparting to each cord a fixed stretch or tension, 

 automatically controlled to insure uniformity. Each unit of five 

 cords is carried through a forming die in which pressure is ap- 

 plied throughout the strip length to obtain the required pro- 

 gressive shape to cover the variable area between bead and 

 crown. 



From the die the strip is fed to a swinging arm having grips 

 at each end by which the strips are held under fixed tension. 

 In this position the strip is cut to a predetermined length, in 

 which there is no further trimming, thus obviating waste ma- 

 terial. The arm is then swung over the core in position to lay 

 the cord strip at the desired angle over the core. The cord 

 strip is next transferred to laying fingers which carry each end 

 in its path around the core; this path being mechanically regu- 

 lated, there can be no deviation from it ; therefore, each strip 

 occupies the same relative position and the initial tension of 

 the cord has been maintained throughout. Placing the bead 

 then follows, after which the strip ends are brought around the 

 bead toe and under it, the ends presenting a line parallel to the 

 bead toe and heel, midway between them. 



Laying the second ply is accomplished in the same manner 

 as the first, the strip ends being laid under the bead heel, abut- 

 ting the ends of the first ply and parallel thereto, thus providing 

 angular locks, under mold pressure, preventing any slippage of 

 the cords whereby the tension is relieved (Dickinson Cord Tire 

 Corporation, 250 West 54th street, Xew York City.) 



RUBBER BUFFING MACHINE. 



Flexible shaft buffing equipment has come into use more 

 recently in tire factories through its utility in removing small 

 imperfections in finished tires, and for eradicating the name 

 and serial number from defective tires. 



In tire rebuilding and repairing, these machines are in- 



Flexible Shaft Buffer. 

 valuable for buffing the inside of the casing to prepare it 

 for the reliner or inside repair. For repairing giant pneu- 

 matic tires, buffing tubes, and tool grinding, this portable 

 device is of much practical use. 



The machine here shown is furnished complete with a J4-h.-p. 

 motor, 10 feet of cord with plug to attach to the electric lighting 

 socket, five feet of 7/16-inch flexible shafting, grinding wheel, 

 and felt bufif. (R. G. Haskins Co., 27 South Desplaines street, 

 Chicago, Illinois.) 



