44 



THE INDIA RUBBER WORLD 



[November i, 1906. 



THE BRISTOL RECORDING GAGE. 



TN many manufacturing industries there are processes of 

 -^ drying, vulcanizing, cooking, and so on, which play an 

 important part in the result or quality of articles produced ; 

 in few, however, is the matter of temperature of such vital 

 importance as in the rnblier manufacture. 



The Bristol Co. 

 (Waterbury, C o n - 

 necticut), are pio- 

 neers in America in 

 the manufacture of 

 recording ther- 

 mometers for record- 

 ing temperature at 

 a distance from the 

 heated bulb. The 

 instrument first de- 

 signed for the pur- 

 pose was applied to 

 recording tempera- 

 ture of heat in a vul- 

 canizer for rubber 

 boots and shoes. 



The illustration 

 shows the interior 

 or working parts of 

 the recorder, which 

 is essentially the 

 well known Bristol 

 recording gage, which enjoys a world wide reputation owing 

 to its simple design and elimination of levers, gears, pin- 

 ions, or multiplying mechanism of any description. 



The principle on which the thermometer operates is as 

 follows ; The bulb is partly filled with a volatile liquid 

 which, when heated, condenses in the small capillary tub- 

 ing which connects the bulb and recorder, through which 

 pressure is transmitted to the pressure tube in the recorder. 

 This pressure is a definite quantity depending on the tem- 

 perature of the bulb. Consequently the temperature of the 

 connecting tube or of the pressure tube in the instrument 

 does not affect the accuracy of the record. In other words 

 temperature is not transmitted, but simply pressure, equiva- 

 lent to the temperature. 



In the use of recording thermometers, the superintendent 

 or foreman has an indisputable w-ritten record of the tem- 

 perature at which the goods were cured. If there is any- 

 thing about the goods which is not just right he knows 

 where to look for the difficulty, instead of spending a night 

 or two at the heater to be sure that the heat has been ex- 

 actly as reported. The use of recording thermometers 

 eliminates guess work, and reduces the process of vulcaniz- 

 ing to a science. 



The value of the recording thermometers applies equally 

 well to the vulcanizing of rubber cloth and similar material, 

 also in steam vulcanizers employed in the manufacture of 

 mechanical rubber goods. For use in the latter a special 

 form of bulb, lead covered to protect it from acids, is em- 

 ployed. The recorder itself may be placed at a distance 

 from the position of the bulb. The regular length of con- 

 necting tube supplied is 25 feet, but this may be made 

 longer. 



The recording thermometers are also suited for drying 

 rooms for crude rubber, and around the power plant for re- 

 cording the temperature of feed water, flue gases, super- 

 heated steam, etc. 



AUTOMATIC TAPE CUTTING MACHINE. 



'nr^IIK machine here illustrated has been designed for cut- 

 -*■ ting India-rubber tapes for golf balls, and elastic 

 washers, and also for cutting other materials of a similar 

 nature to rubber. The illustration shows a machine com- 

 plete with countershaft ready for fi.xing. The material to 

 be cut is wrapped upon a mandril fi.xed between the centers 

 of the fast and loose headstock, and is only limited in length 

 of sheet to be cut by the diameter that the rest will permit 

 when coiled on the mandril. 



The operation of the machine is as follows: The mandril 

 is first put into the machine wuth the rubber wound upon 

 it. The set collars on the automatic stop arrangement are 

 adjusted so as to stop the tool at the end of the mandril, 

 and the machine is put into operation by a countershaft. 

 The small clutch on the cam shaft is put into gear by a 

 small handle at the right of the machine. When the tool 

 advances to the set depth of cut, being pressed forward by 

 the cam, it then immediately springs back out of contact 

 with the rubber, and the rest with the tool travels forward 



along the bed through the action of the crank and hutching 

 motion at the right hand of the machine. As soon as the 

 set amount of travel is completed, the hutching pawl recedes 

 due to the action of the crank, and while this is taking place, 

 the cutter again advances and withdraws as before, after 

 which the travel is again repeated, and so on until the whole 

 length of the rubber on the mandril is cut into the necessary 

 strips or tapes. The machine is complete with splasher 

 guard to prevent the water which is used for lubricating the 

 tool when cutting, from being thrown about the works ; the 

 cutter holder is arranged to carry the end of a small hose 

 pipe bringing the water to the cutter at a pressure. When 

 the cutter has arrived at the end of the mandril, the rest can 

 be readily brought to its first position by a handle fixed upon 

 the screw in the center of the bed at the right hand, care 

 being taken that the hutching paul is liberated from contact 

 when bringing the carriage back ; also that the direction of 

 revolution of the mandril when the small clutch is in gear 

 operating cam shaft must also be the same, this direction 

 being indicated on everj' machine made. Made by David 

 Bridge & Co., Castleton, Manchester, England. 



