Woolen and worsted cam-looms ; Woolen and worsted fancy looms ; Woolen and worsted loom fixing ; Plain looms ; Fixing looms ; Loom attachments ; Automatic looms ; Dobbies ; Leno at by International Textbook Company & International Correspondence Schools

Author:International Textbook Company & International Correspondence Schools
Language: eng
Format: epub
Tags: Looms, Textile machinery, Weaving
Publisher: Scranton : International Textbook Co.
Published: 1906-03-25T05:00:00+00:00

Digitized by

Google

alternately on each other, their relative speeds will be as the number of teeth of one are to the number of teeth of the other. For instance, if it is required to have five picks placed in the cloth while the cam is revolving once, as in this case, then the proportion of the teeth in the gear on the cam-shaft to the teeth of the gear on the auxiliary shaft is as 2 to 5, since the cam-shaft makes only one revolution to every two picks.

To illustrate this, a 60-tooth gear is found on the auxiliary shaft and it is desired to know what gear shall be placed on the cam-shaft in order to give one round of the cam to five picks of the loom. This will resolve itself into the following equation, letting x represent the number of teeth in the gear on the cam-shaft:

^:60 = 2:6

Multiplying the extremes and means together gives bx = 120. Since bx = 120, x will be one-fifth of 120, or 24, which will be the required number of teeth in the gear on the camshaft. That is, if a 24-tooth gear on the cam-shaft of the loom is driving a 60-tooth gear on the auxiliary shaft, then the loom will run five picks while the auxiliary shaft makes one revolution. By following this method the gears may be obtained for three-, four-, five-, or six-harness work.

16« Another rule for finding the required size of gears on cam-shafts when driving auxiliary shafts may be stated as follows: •

Rule.— Multiply the number of teeth in the gear on the auxiliary shaft by two and divide by the number of picks to the round.

Example. —What must be the gear of the cam-shaft on five-harness work, if the auxiliary shaft has a 60-tooth gear?

Solution. —^Applying the rule just stated, 60 X 2 = 120 120 -H 5 = 24

The cam-shaft should have a 24-tooth gear. Ans.

Very frequently it may be found inconvenient to have only two gears. The two shafts are placed at a fixed distance

Digitized by

Google

apart, and the gfears must therefore be of such a diameter as to suit this fixed distance; consequently, it will frequently happen that in changing^ from one number of cams to another, not only the diameter, but the pitch of the teeth, will have to be altered. It is desirable to avoid this as far as possible, and indeed to avoid the necessity of making: the gears of such diameter as to suit the distance between the shafts. This is done by introducing an intermediate gear, which becomes simply a medium for commimicating the power without in any way altering the relative speed of the two shafts; therefore, the same pitch of teeth may be preserved throughout, and in figuring to obtain the gears the only thing to observe is the relation of the gear on the cam-shaft to that on the auxiliary shaft, leaving the intermediate out of the calculations entirely. In fact, the method is the same as in the first case, where no intermediate was used.

Download

Copyright Disclaimer:
This site does not store any files on its server. We only index and link to content provided by other sites. Please contact the content providers to delete copyright contents if any and email us, we'll remove relevant links or contents immediately.