March I, 1917.] 



THE INDIA RUBBER WORLD 



331 



stock, rubber cylinders with air-filled centers and endless, soft 

 rubber bolsters are now in genera! use. 



In operation the hide is passed over the rubber cylinder or 



bolster against which it is held by a feed roller. The rubber 

 bed yields to the surface inequalities, while the operating blades 

 completely remove the hair from the hide. 



MAKING WEATHER-STRIPS. 



One of the many minor lines of manufacture in which rubber 

 forms an important part, is that of the ordinary weather-strip 

 for doors and sashes. Such strips generally utilize only low 

 grade reclaimed stock in the form of rubber-coated thin fabric 

 and light cloth insertion packing. The rubber is combined with 



wood or metal strips in the form of an open tubular fold, with 

 the edges held securely in the body of the strip. In making the 

 double edge wood strip, the rubber sheeting is first cut accurately 

 into strips in a slitting machine. The edges are glued and the 

 strips are inserted in grooves in the wooden strips cut to receive 

 the glued edges of the rubber. The most common form of 

 weather-strip is that made by folding the rubber into strips of 

 sheet brass, zinc or copper. This form is inconspicuous when 

 applied and is the only kind adapted to many locations, such as 

 around sashes of railway coaches for excluding dust and prevent- 

 ing vibration. These weather-strips vary in width from % to 

 Yi of an inch and are often made in continuous lengths of 100 

 feet. 



The manufacture of weather-strips is accomplished in auto- 

 matic machines with special dies and folding devices to form 

 the flat metal ribbon around the rubber, with the edges folded 

 in such a manner as to avoid cutting the rubber. After forming 

 the strip the machine automatically punches holes at regular 



intervals in the metal for tacking the weather-strip in place. 

 The machine shown in the illustration takes the metal- 

 lic strip from a stock roll and folds it over a strip of rubber 

 or other flexible material. The feature of this machine is a die, 

 through which the metal and rubber strips are simultaneously 

 drawn, and which folds the metal over the rubber. A is the strip 

 of metal formed in a roll and mounted on the frame of the 

 machine. 5 is a coil of wire which passes through the die and 

 forms the reinforcement for the completed strip. C is a roll of 

 rubber of suitable width. These three parts are passed over 

 suitable guides and into the forming die D, which folds the metal 

 strip around the wire and clamps the rubber strip. As the metal- 

 lic strip A is unwound from the stock roll it passes under a 

 buffing wheel E, being forced up against this wheel by means 

 of a pedal F. The strip then passes between rollers G and H and 

 thence to the guide / where it meets the wire and strip of rub- 

 ber. As the metallic strip passes between rollers G and H, it is 

 perforated at certain distances apart by means of punches 

 located in the rim of the roller G. The three parts pass through 

 the guide / and thence through the forming die. As the com- 

 pleted strip emerges from the die, it passes over a varnishing 

 or lacquering device /, which covers the metal parts of the strip 

 with a protecting coat. After the first few inches of completed 

 strip is formed, the end is attached to a clamp K, which is hooked 

 into a sprocket chain L driven in the direction indicated. As 

 soon as a sufficient length of strip is pulled through the die by 

 means of the sprocket chain, or when the end of the chain is 

 reached, the strip is cut off near the die and the clamp is returned 

 and again attached to the new end of the strip, after which power 

 is applied to the chain to force additional stripping through the 

 die. A section of the completed strip formed by this machine 

 is shown at M. 



MACHINERY PATENTS. 



INTERNAL PRESSURE TIRE VULCANIZING MOLD. 



T TNDER certain conditions the use of steam, air or water as 

 ^^ internal pressure producing agents in curing tire casings 

 has resulted in permeation of the structure. This is obviated in the 



present invention by 

 maintaining the water 

 tliat fills the casings un- 

 der hydraulic pressure, 

 while the expansion due 

 to the heat of vulcaniza- 

 tion is controlled in a 

 special expansion cham- 

 ber. 



The illustration shows 

 an ordinary press vul- 

 canizer in which are 

 stacked the molds A 

 containing the tires to 

 be cured. Previous to 

 bolting down the head, 

 water under pressure is 

 conducted to the indi- 

 vidual molds and the 

 compression chamber B, 

 and the air in the tires is 

 forced out through valves C. Tlie compression chamber being 

 closed, the air cannot escape and is hydraulically compressed in 

 the chamber serving as a cushion that compensates for the expan- 

 sion of the water in the tires. [Nelson W. McLeod, St. Louis, 

 Missouri, assignor to American Motors Tire Co., Detroit, Michi- 

 gan. United States patent No. 1,213,224.] 



In a previous invention granted to the same inventor and 

 the same assignee, water is compressed in a cylinder provided 

 with a piston and coiled adjustable spring that controls the ex- 



