The spaceband box is fastened to the face plate by means of a screw and dowel pins.
The spacebands slide down through the box, suspended by their lugs, on two inclined rails. The lower spaceband rests against a raised projection or hook on the inclined rail. The bottom end of the spaceband rests against the chute plate. Escapement of the spaceband is effected by two pawls which lift the spacebands over the rails, allowing them to drop into the assembling elevator.
The pawls are located in the right-hand side of the spaceband box, front and back. These pawls are connected to the pawl levers by the spaceband pawl lifting screws, and held in place by the rails and pawl springs. When the pawls are at their lowest position, they are forced under the ears of the spaceband by the pawl springs.
The pawls get their motion in the following manner: When the spaceband key is touched the cam is released and turns the same as the regular keyboard cams. This raises the spaceband keyrod against the tension of the spring at the bottom of the keyrod. The keyrod raises the right-hand end of the spaceband keylever. This lowers the left-hand end of the keylever, on which the box lever rests. This permits the pawls and levers to drop of their own weight. When the keyrod cam returns to normal, the spring on the keyrod pulls the keyrod and the keylever to normal, thus raising the pawls and levers by spring action.
The movement of the pawls is controlled by the screw in the back pawl lever which rests on the spaceband keylever. When the pawls are at their lowest position, the bottom of the slot in the adjusting screw is resting on the keylever. They must go 1/32 an inch below the inclined rails on their full down stroke. To make this adjustment, disconnect the keyboard belt from the pulley, touch the spaceband key, turn the rollers by hand until the pawl levers are in their lowest position, disconnect the keylever from the adjusting screw and turn the screw.
The chute plate, against which the lower right side of the spaceband rests while suspended in the spaceband box, must be low enough so that when raised by the pawls, the bottom of the spaceband will be released before the top; if not, they will catch and hang in the box. Whenever it is necessary to make this adjustment it can be accomplished by bending the chute plate a trifle.
When the first spaceband is being raised by the pawls, the weight of the other being against it would cause the next one to raise by friction unless it were prevented. This is prevented by the center bar which is fastened to a bracket at the top of the box. The distance from the vertical stop on the box rails to the pins on the center bar should be just enough for one spaceband to raise, the pins holding the second band from raising. By loosening the screw in the bracket and moving the bar, adjust so that the distance from the vertical stop on the rails to the pins is just enough to permit one spaceband to raise, the pins holding the second one. As there are three kinds of spacebands in use—thin, thick, and extra thick—the above adjustment can only be made so as to use one thickness at a time.
The two chute rails at the bottom of the chute guide the spacebands into the assembling elevator. The spacebands will have a tendency to catch on the assembling elevator rails, and not settle down in the assembler, if the rails are worn. There should be just room enough between the rails for a spaceband to slide without binding.
TO REMOVE SPACEBAND BOX
Push in controlling lever. Take hold of cam No. 1 and back the cams until the second elevator descends to its safety latch. Hold the spaceband transfer lever with the right hand and press downward with left hand on the releasing lever in the first elevator top guide. Allow the spaceband transfer lever to move over into the intermediate channel. Push the spacebands back into the channel. Remove the screw on the right-hand side of the electric light bracket and move the bracket to clear the box. Remove the large screw in the center of the box and lift the box off the dowel pins.