THE INDIA RUBBER WORLD 



735 



IMPROVED AUTOMATIC MILL AND MIXER. 



Eiulosed. automatic rubber mixers are now accepted as 

 Standard equipment in rubber mills. The machine here shown 

 has demonstrated its efficiency in breaking down crude rubber 

 and mi.xing compounds maximum quantities. 



The mixer consists of 

 an enclosed trough, in 

 which operate rotating 

 blades of special con- 

 struction, both trough 

 and blades being hol- 

 lowed for cooling and 

 heating purposes. The 

 rubber and compound- 

 ins ingredients are fed 

 into a hopper and the 

 finished batch is dis- 

 charged by the turn of 

 a valve, through the 

 door at the bottom of 

 the machine. 



.\ recording ther- 

 mometer records the 

 temperature of the mix and also shows how many batches are 

 mixed daily, and a timing device indicates by sight or sound 

 when the batch is finished. 



These mixers are made in two sizes, No. 3 and No. 9. The 

 former will handle a batch of approximately 150 pounds of 1.5 

 gravity stock, and the latter, 450 pounds. Individual motor drive 

 is commonly used but the machines may be driven from the mill 

 line. (Birmingham Iron Foundry, Derby. Connecticut.) 



r COMBINED TIRE BUILDING MACHINE AND LOOM. 



I This machine makes it possible to begin the construction of a 

 • tire carcass on the doubling and twisting machine, where each 



No. 9 



■RV Mixes. 



thread, before becoming a part 



cord, is drawn through 



After being rubberized, the threads are ingeniously woven on a 

 magnetically operated loom and formed into a fabric on a double 

 curve to approximate closely the final position of the fabric in 

 the tire, as regards curve of the walls and circumference of 

 the tire. 



The saturated threads are then passed over electrically warmed 

 pads that make them soft and sticky, when the skim-coat rubber 

 is fed between the rolls and adheres to the warmed rubber ot the 

 plies, welding them closely together and insuring the expulsion 

 of air. 



The carcass made by this machine is unique in that it does 

 away with all laps or joints. There is one continuous ply from 

 start to finish, in which the distribution of warp threads may be 

 regulated to give varying strengths for first ply, bead section, 

 etc.. The fabric contains one starting and one finishing end, with 

 no waste of fabric, there is no trimming, and but little auxiliary 

 stitching. 



These machines will make tires up to 34 by 4 inches, with a 

 capacity of two tires per hour, it being assumed that one man 

 will be able to take care of eight machines and thus turn out 

 sixteen tires per hour, (.'\utomatic Tire Machine Corporation, 

 Buffalo, New York.) 



The Sch.vffer Automatic Tire Builder. 



rubber solution and impregnated, insuring a thorough distribution 

 of rubber throughout the fabric, thus contributing largely to the 

 elimination of one of the troubles that usually cause separation of 

 the plies, internal friction and blow-outs. 



MACHINERY PATENTS. 



MACHINE FOR BUILDING CASINGS AND TUBES. 



THIS machine is provided with a rotatable annular channel- 

 shaped form within which the tire casing or tube is built. 

 Two annular portions secured together and arranged to be sepa- 

 rated after the tire is built permit the removal of the tire from 

 the form ; a stitching device stretches the material from wliich the 

 casings are formed, as it is placed within the form and shapes 

 the tire casing. 



The tread portion and side walls of the casing are first placed 



B.\N.\-ER Tire Builder. 

 within the form after which the breaker strip is placed upon 

 the tread or if desired the breaker strip may be applied to the 

 tread before placing in the form. The form is preferably oper- 

 ated at a slow speed by depressing the treadle A, rocking the 

 lever B into position to move friction roller C into engage- 

 ment w-ith the belt, and thus slowly rotating the form. 



The fabric or cord is then placed within the form, and the 

 stitching wheel D operated to press the fabric within the side 

 walls and tread portion of the tire. The cushion strip being 



