The catch is fixed to the framework of the machine, and rests on the square casting fixed to the end of the cylinder. As the cylinder moves out, the catch comes in contact with the rounded edges of the square and in this manner the cylinder is turned. There is also another catch fixed underneath, but it is not in contact with the cylinder, and is adjusted so that it can be raised up in contact and the top catch raised from contact with the cylinder. This permits the cylinder to be turned back when a lost pick has to be found.
Fig. 19. Iron Bar Supporting Batten Frame.
At each side of the batten frame toward the lower end, an arm is fixed. To these arms rods that extend downward are attached, and each rod is fixed to an arm that is set-screwed on a shaft supported by brackets fixed to the arch of the loom. At the end of this shaft another arm is fixed and is connected to the eccentric rod that is attached to the clamp that encircles the cam or eccentric. The cam is for the purpose of imparting motion to the batten. The cam generally used to operate the batten is about three and one-half inches from center of movement to extreme outside length of cam. The cylinder is moved out from the needle board from two to three inches.
For the saving of cards, a great deal depends upon the movement that is imparted to the cylinder. The less movement that can be given to the cylinder, the better; that is, of course, when obtaining the results required. The cylinder ought to be about one-quarter inch from the needle points when commencing to turn. Sometimes it is necessary to have the cylinder a little farther out, especially when the cards have been stored in a damp place and become warped so that they do not lie flat on the cylinder. In this case, unless the cylinder is a little farther out from the needle points when commencing to turn, the edge of the card will catch on the needle points. This will throw the cards off the pegs and cause a pick-out. If the distance traveled by the cylinder is too short, it causes too sharp a turning of the cylinder, which has a tendency to jump the cards from the pegs; and if the cylinder moves out too far, there is too much friction on the working parts, as the larger distance has to be traveled in the same space of time as the shorter distance.
Fig. 20. Spindle Cylinder Motion.
When setting the batten frame by either the set screws or the arms to which the set screws are attached, the principal point is that the cylinder must be flat against the needle board, both at the top and bottom of the board, and have the needle points as near the center of the holes in the cylinder as possible. It is particularly desirable that all points be square and straight with the batten motion, because the batten, moving from a top connection, performs an arc movement, and if the cylinder does not lie flat against the needle board, some of the hooks will not be pressed far enough off the griffe, or the points of the needles will come in contact with the sides or bottom of the holes in the cylinder and in that case, hooks will be down when they ought to be lifted. Fig. [18] shows the cylinder set crooked with the needle board.