September 1. 1919] 



THE INDIA RUBBER WORLD 



New Machines and Appliances. 



C-H SOLENOID BRAKE. FOR RUBBER MILL DRIVE. 



THE i.WiTALL.^TiON of brakes and clutches on driving 

 shafts for the instantaneous stopping of rubber mill ma- 

 chinery is now almost universal in the large rubber plants, 

 and many of the smaller plants are employing this means of 

 reducing the hazard assumed by workmen engaged at the mixing 



C-H Magnetic Clutch Brake on Washer Line. 



rolls, washers, crackers and calenders. Electrically operated 

 brakes and clutches have the advantage of remote control. This 

 is a very important feature as it permits the releasing of these 

 ■devices by switches located conveniently to the workmen. 



A brake which is applied by gravity and released by an 

 «lectro-magnet is especially desirable because it is positive in 

 its operation. A band brake of this type consists of a cylindri- 

 ■cal cast-iron shell enclosing a bobbin-wound coil, which when 

 ■energized actuates a plunger. The brake band of woven asbestos 

 lining is drawn taut by means of a weighted lever, which is 



AND Clutch .A.re Operated by Movement of 

 Cradle .Switch over Washers. 



attached to the solenoid plunger. When the lever is in its 

 normal position, the brake is applied. Upon starting the motor 

 the current energizes the solenoid, thus lifting the lever and 

 releasing the brake. As no latches of any kind are used, there 

 is no possibility of the brake failing to function. Any derange- 



ment in the solenoid brake system causes the brake to be 

 applied, thus resulting in a safe condition. 



In a recent test a 200-h.-p., 590-r.p.m. motor driving three 

 mills without load at full speed, was disengaged by a cut- 

 oft device, the brake and clutch being operated at the same 

 time. A chronograph employed to measure the movement of 

 the drive-roll peripheiy indicated only 4 inches subsequent 

 to the operation of the cut-off device. The same test was re- 

 peated with the brake inoperative and the chronograph indi- 

 cated a movement of 86 inches. When neither the brake nor 

 clutch was used, the rolls traveled 376 inches, or about four 

 revolutions. Under normal working conditions, with the mills 

 loaded, the movement of the rolls will necessarily be still less 

 than the minimum of 4 inches obtained in this test. 



It is thus shown that although a clutch alone affords a large 

 measure of protection, complete protection is impossible without 

 the use of a brake. (The Cutler-Hammer Manufacturing Co., 

 Milwaukee, Wi 



A NEW THREE-ROLL CALENDER. 



The advantages claimed by the makers of this recently de- 

 signed inachine are that the calender, reducing gear, and motor 

 are all mounted on a straight line bed-plate, the design is com- 

 pact, and the reducing gear is mounted on roller bearings 

 and provided with splash oiling system while the jack-shaft 

 bearing is combined with the gear-reducing housing. 



The W-S-M Cale.xdek. 



The calender frame is of the hollow cast-iron type and heavily 

 ribbed. It is firmly tied across the top with two cast-iron 

 separators and at the bottom with the cast-iron base plate. The 

 rolls are cast iron with chilled face, finished all over and ground 

 to size. They are cast hollow, bored out to insure uniform 

 thickness, and ground concave and convex to suit their re- 

 spective work. They are fitted with packing boxes for water 

 connections and any or all of them can be removed without 

 removing either frame from the base plate. Each roll is 

 carried on cast-iron bearing shells lined with hard bearing 

 bronze. The bearing bushings have large oil grooves and 

 are lubricated from sight feed glass oil-cups mounted on the 

 frame. 



The calender is equipped with cut herringbone-gears through- 

 out except the wind-up gears which are cut spur-gears. 



The upper and lower rolls can be adjusted to any desired open- 

 ing by a hand-wheel located on the side of the frame. It consists 

 of a series of bevel and worm gears and screws that act 

 directly on the bearing shells. Either end of either roll can 

 be lowered or raised by engaging or disengaging the clutches 



