256 



THE INDIA RUBBER WORLD 



January 1, 1921 



COMPENSATING COUPLING FOR MILL LINES 

 Rubber inaiiulacturers will be interested in the perlormance 

 of this flexible coupling, a feature of which is a large overload 

 capacity equal to five or six times the normal value. 



The coupling consists of two flanged bosses, one keyed to 

 each shaft end. a steel spring and a shell. The continuous siiring 

 is placed in the pitched cross grooves around the circumference 

 of the flanges, filling the grooves at the outer edges only. Under 

 a normal load, the spring is unsupported between* the outside 

 ends and is consequently very flexible. As the overloads in- 

 crease the spring bears further and further along the faces of 

 the grooves and the unsupported span of spring becomes less 

 and less, the increase in load is thus set off by the decrease in 

 span. The stress in the spring docs not therefore increase 

 proportionately with the load. 



The torque is equally distributed over a large number of 

 units. The spring acts on the outsides of both flanges, thus 

 permitting the coupling to be small in diameter and light in 

 weight. The shape of the .spring is such that no end thrust is 



Flexible Shaft Coupling 



produced between the shafts, which are free to float within 

 limits. The only force exerted between the two shafts is torsion. 

 The small diameter and the freedom from end thrust allow 

 the cover ring to be a plain cylindrical shell with a grease- 

 retaining ring at each end. This shell is not put on until after 

 the bosses are keyed to the shafts. The safe running speed of 

 this coupling is higher than is ever required in practice. The 

 load on each driving unit is comparatively light, and as the 

 spring chamber is filled with grease, no wear takes place when 

 the shafts are out of line.— Wellman Bibby Co. Limited, 36 

 Kingsway, London, W. C. 2, England. 



NEW ELEVATOR CONTROLLERS 



The C-H line of D. C. and A. C. elevator controllers has been 

 replaced by newer types of simpler construction. The general 

 design is the same. The new features are : standard carbon-to- 

 copper power contacts, which are non-freezing and quiet in oper- 

 ation ; and. time limit acceleration by a simple dash-pot relay, 

 which is accurate in operation and provides smooth acceleration 

 regardless of load conditions. The resister, formerly automatically 

 inserted in the solenoid circuit, has been omitted, as the coil is 

 of sufiicient size to prevent overheating on intermittent duty. 

 without having to reduce the current when the plunger reache.s 

 the end of its stroke. — Cutler-Hammer Manufacturing Co., Mil- 

 waukee, Wisconsin. 



OVERHEAD CONVEYING SYSTEM FOR RUBBER FACTORIES 



The short-turn overhead trolley, shown in the illustration, is 

 of undoubted interest to rubber manufacturers, particularly tire 

 makers. It is used to convey a variety of materials, also finished 

 tires mounted on their cores, to the curing room and for carry- 

 ing the cores back to the tire-building room again, etc. It is 

 a simple system, designed to take up little space, and it is easily 

 installed. 



sists of two channels held in place by clamps and the weight 

 is carried by supporting points naturally provided by the build- 

 ing. Additional supporting memliers are used only where neces- 

 sary, such as for carrying corners or switches. The trolley runs 



Overhead Tka( k i.\ a Concrete Builuing 



on the top of the flanges. All the trolley wheels are supplied 

 with ball bearings and are furnished without flanges, consequently 

 there is no binding or jamming against the track on curves. 

 Due to these special features of construction sharp curves in the 

 track as small as 18-inch radius are safely used. The track may 

 be wired to operate electric hoists. 



The trolleys are made with two, four, or eight wheels, and 

 have a carrying capacity of 1,(XX), 2,500 and 5,000 pounds re- 

 spectively. — S-T Engineering Corporation, Buffalo, New York. 



EILECTRICALLY HEATED GLUE-POT 



While the electrically heated pot here pictured was designed for 

 heating glue, its utility in other directions is apparent to practical 

 rubber men. 



It is a 2-quart electric pot of the dry type, eliminating the water 

 bath entirely. The glue-pot consists of a copper vessel contained 

 in a steel case. It fits snugly, makes a perfect thermal contact 

 with the heating element, and may be ca.'^ily taken out for clean- 

 ing. 



One of the strong claims made for this pot is. that tlie direct 



iiS 



^ 



Drv-Tvpe Gh e-Pot 



contact insures the glue being at the right temperature all the 

 time, that it will not burn, and that the heater cannot be burned 

 out. — Westinghouse Electric & Manufacturing Co., East Pitts- 

 burgh, Pennsylvania. 



AN IMPROVED TIRE BUILDER 



Of particular interest to tire ni.mufacturers at this time when 

 production costs are paramount is the recent improvement in 

 tlie Hermann tire building machine. Having a capacity of ten 

 30 by 354-inch tires per hour and a proportionate number of 

 larger sizes, this machine automatically guides, positively centers 

 and marks the fabric before it is placed under tension. It is 



