FIG. 81.
PICK-AND-PICK LOOM.
The majority of box looms are made with movable boxes at one side of the loom only, so that single picks of any colour cannot be put in the cloth at will. As it is very desirable in many fabrics to use single picks of a colour or count of weft, it is necessary to have movable boxes at both sides of the loom, and where this is the case it is usual to have picking mechanism which will allow of several picks being made in succession from either side of the loom. If the matter be carefully thought over, it will be easily apparent that even with drop boxes worked quite independently of each other at both sides of the loom, if the picking mechanism is of the ordinary kind—viz. to pick once from each side alternately—it would be impossible to obtain that variety of changes in the shuttles which is in many cases necessary. In a loom with two boxes at each side worked independently, it would be impossible to obtain single picks alternately of two colours or counts. But by being able to pick twice in succession from each side this can be done. By going through all the changes possible with a given number of boxes, the advantage of this kind of picking arrangement will be very apparent, in the command it gives over any shuttle in the series for any pick. It is therefore necessary to have the picking mechanism aforementioned in order to allow of all the boxes being emptied at one side if required. A loom of this character is called a “pick-and-pick” loom; the picking motion is sometimes called a “pick at will” motion. The loom which we take as an example is one on the Diggle’s chain principle. There are two chains, placed at one side of the loom for convenience. Both chains are on one barrel, A ([Fig. 82]). The chain for working the boxes at the right-hand side of the loom operates the lever B, and the left-hand chain operates the lever C, the fulcrum of both levers being at D. When these levers are lifted they lift the levers E and F, and when E is lifted it lifts the boxes at the right-hand of the loom, and when F is lifted it lifts the left-hand boxes. The connection of the left-hand boxes with the lever F is shown at [Fig. 83]. The shaft G is placed under the loom, and the left-hand boxes are connected to the lever H, which is fast to the shaft G. The lever F is also fast to the shaft G, but the lever E rides loosely upon this shaft, which merely serves as a fulcrum for E. From these two figures it will be clearly understood how the boxes may be worked independently at both sides of the loom by two chains placed side by side upon the barrel A.
FIG. 82.
FIG. 83.
FIG. 84.
