THE INDIA RUBBER WORLD 



431 



MINERAL RUBBER CRACKER. 



Mineral rubber has a wide range of usefulness in rubber manu- 

 facture and occupies an important place as a standard ingredient 

 in rubber compounding. As this material is supplied by the 

 makers in rather inconvenient form, the rubber manufactures 

 find it necessary to "crack" it. This is effectively accomplished 

 by passing the brittle mineral rubber through a crusher that 

 reduces it to a size suitable for milling. 



The machine shown in the accompanying illustration performs 

 the operation of cracking in a satisfactory manner. It is pro- 

 vided uiili an .imple hopper and with a discharge extending the 



Day Hercui.es Crusher. 



full length of the bottom. The belt-driven crusher shaft is pro- 

 vided with heavy breaking lugs that pass between stationary lugs 

 on each side of the cylinder. The machine is 33 inches high, 42 

 inches long and weighs 450 pounds. (The J. H. Day Co., Cin- 

 cinnati, Ohio.) 



INDICATING CALIPERS. 



This useful hand-tool that is a modified outside caliper, com- 

 prises a rule, a magnifier and an indicator. It is supplied in 

 two sizes, the 2-inch being graduated in 1/100 inches. Every 

 tenth graduation is 

 marked 10, 20, etc., to 

 100 and repeated to 

 200. The fifth interven- 

 ing graduation is made 

 longer to facilitate quick 

 reading. The scale is 

 three times actual meas- 

 urement. 



The 3-inch indicating 

 caliper is graduated in 

 1/64 inches. Every eighth 

 graduation is marked 1, 

 2, 3, etc., to 8 and re- 

 peated to three inches. 

 The fourth intervening 

 line is made longer for 

 easy reading. The dis- 

 tance between points on 

 the dial is twice actual 

 measurement. (Indicating Calipers Co., 506 East 19th street. 

 New York City.) 



MACHINERY PATENTS. 

 MOLD FOR MAKING RUBBER ARTICLES. 



A/f oij)S made of cast iron with the mold surface machined ac- 



^"■*- cording to the contour of the article are very expensive. 



So also, molds of white metal cast on a metal matrix involve 



large expense in making 



the matrix. 



A very satisfactory sand- 

 cast mold for the manu- 

 facture of rubber articles 

 may be made by employ- 

 ing an aluminum alloy 

 which is free from ingre- 

 dients which will unite 

 with the sulphur com- 

 pound in the rubber ar- 

 ticle. The alloy consists of 

 approximately 97 per cent 

 Aluminum Allov Toy Mold. °^ aluminum and three 

 per cent of magnesium 

 and may be sand-cast with a smooth surface to be effectively 

 used without machining. (Fred Thomas Roberts, Cleveland, Ohio, 

 United States patent No. 1.329,312.) 



PROCESS OF TREATING TIRE FABRIC. 



The object of this invention is the introduction of a lubricant 

 into pneumatic tire fabric, in the form of a suspension or emul- 

 sion in the yarn, threads or cords from which the fabric is woven, 

 or into the woven fabric 

 itself. 



The form of apparatus 

 used is shown in the il- 

 lustration. It consists of 

 twin cylinders, A con- 

 taining the liquid lubri- 

 cant and B. the impreg- 

 nating cylinder, contain- 

 ing the fabric to be 

 treated, wound on a ser- 

 ies of parallel rods to ad- 

 mit the free contact of 

 the emulsion or suspen- 

 sion with the inside of 

 the roll. Mounted on the 

 head is a gage C, to in- 

 dicate the pressure on 



~ T^ T the inside of the cylin- 



TiRE Fabric Impregnatoe. , , . , t^ 



dcr, and an air-valve D, 

 for the escape of the confined air. 



The cylindrical tanks are united by a pipe connection. A valve 



E, controls the flow of the lubricating solution. A steam pipe 



F, controlled by a valve G, connects the cylinder B, with a supply 

 of steam. 



In operation the valves E and G are closed, the detachable 

 head H removed and the roll of fabric I placed in the cylinder. 

 The head being secured in place, low-pressure steam is admitted 

 to the cylinder through valve G. This heats the fabric, and drives 

 out the air through valve D. Valve G is then closed and valve 

 E is opened. Cold emulsion or suspension from tank A enters 

 cylinder B and comes in contact with the hot water vapor. Con- 

 densation follows, automatically producing a vacuum which al- 

 lows the emulsion or suspension to permeate the interstices of 

 the fabric. 



.•\fter this takes place atmospheric pressure is admitted to cylin- 

 der B and the surplus fluid pumped back into the tank A through 

 the pump J. The fabric is then removed and thoroughly dried, 

 leaving the lubricant in intimate contact with the fibers. (Wil- 

 liam C. Carter, Radnor, Ohio, assignor to The Goodyear Tire & 

 Rubber Co., Akron, Ohio. United States patent No. 1,327,904.) 



