June. 1, 1916.] 



THE INDIA RUBBER WORLD 



475 



New Machines and Appliances. 



THE THROPP REDHCTION GEAR DRIVE. 



MOTOR drives are becoming an incUspen.sable aid to the 

 operation of modern rubber mills where efficiency is recog- 

 nized as one of the main factors of increased production. 

 Thropp has designed a new 100-horse power drive that 

 is shown equipped with a special General Electric motor of 

 the ventilating type. This is entirely enclosed and provided 

 with an outside air suction vent and discharge pipe. Both 

 motor and drive are bolted to a heavy continuous bed plate, 

 the motor being connected to the jack shaft of the drive 

 by a flexible coupling that allows the motor shaft to oscillate 

 and the double helical gears to float. The jack shaft pinion 

 is machine cut from a solid forging and drives the large cast 

 iron main gear, both of which are the '"iMaag," double helical 

 cut type of gearing. They are enclosed in oil-tight guards 

 and run in a bath i>f oil. the bearings being of the newest 



rmg oiling tyi>e. I he main ilrning sliaft runs 10(1 revolu- 

 tions and the jack sliaft at 575 revolutions per minute. The 

 drive is shown connected to a 2-roll rubber mill. [William 

 R. Thropp & Sons Co., Trenton, New Jersey.] 



A NEW APHON FEED FOR MIXERS. 



The value of a practical mixing apron is instantly recog- 

 nized by progressive rubber men, particularly those who 

 have had experience with the ordinary apronless mill. Two 

 illustrations are given here of a device of this character 

 that has recently attracted favorable comment. The first 

 IS a front view of the mechanism, ready to be attached to 

 a mixer, while a rear view of the apron is given in the sec- 

 ond illustration. ■^' 



This device consists of a cast iron pan upon which a 



the mill. The batch is fed to the mill in the usual manner; 

 the apron, however, catches the particles that have not 

 massed and automatically returns them to the rolls. 



The sliding mechanism makes it possible to drop the top 

 roll so that the finished batch is easily removed, after which 



fastened bearings and brackets supporting two rolls and also 

 a sliding mechanism carrying a third roll. The apron, in the 

 form of an endless belt, travels over these rolls and is driven 

 by the top roll through direct contact with the front roll of 



the roll is again placed in the original position and the mill 

 is ready for another batch. 



Among the advantages claimed for this mixing apron, 

 safety comes first, for it reduces the possibility of injury to 

 the workman. It eliminates the dust, so troublesome and 

 expensive in ordinary mixing operations, and, moreover, 

 delivers a finished batch of the same weight as the original 

 amount placed in the mill. The saving of 30 to 35 per cent 

 of the time consumed in mixing is another important feature 

 and at the same time the material is delivered in a thoroughly 

 massed condition. [Morgan & Wright, Detroit Rubber 

 Works. Detroit, Michigan.] 



THE ALLEN TITBE SKIVING MACHINE WITH MOTOR DRIVE. 



An extremely well designed, self contained, inner tube skiving 

 machine is herewith illustrated, showing the consistent progress 

 that is being made in labor saving tube building machinery. 

 The slide is operated by a lever 

 which carries a hollow brass man- 

 drel of the correct diameter for a 

 given size tube. This mandrel is 

 clamped in alignment with the tubu- 

 lar knife that revolves from 2,000 

 to 2,500 revolutions per minute. 

 The end of the brass mandrel is 

 tapered for a given length of skive. 

 The tube is then thrust through 

 the center of the man- 

 drel and folded back 

 over the tapered end. 

 The slide is then 

 forced forward by 

 the lever until it 

 comes in contact with 

 the revolving knife 

 of water is automatically released at the 

 also automatically shut oflf when the 

 slide is brought back to its original position. This feature pre- 

 vents undue waste of water besides being cleaner, as the excess 

 of water would become sloppy and objectionable. Also the little 

 shutter device over tlie knife, which operates automatically, pre- 

 vents the hands of the operator from coming in contact with 

 the knife when placing the end of the tube in position. The 



and a sufficient tlo 

 time of contact which 



