Patent GB-190310181-A (GB)
Title: Improvements in Sewing Machines.
Inventor: DAVIS ISAAC PARSONS
Filed: 1903-05-05
Granted: 1903-06-25
Abstract: 10,181. Davis, I. P. May 5. Blind stitching machines ; overedge stitching machines; work-supports ; presser-feet.-Relates to the class of machine described in Specification No. 12,868; A.D. 1899. The work-support d is carried by an arm e pivoted to the frame at f. The cloth plate consists of a V-shaped hollow block n, which is partly cut away, as shown in Fig. 1, to expose the feed-dog and allow the needle to pass. A spring g, the tension of which can be regulated, presses the work-support upwards, its movement in that direction being limited by an adjustable screw. The presser-foot k is \/-shaped to fit the cloth plate, on which it is pressed downwards by a strong spring m'. Needle holders; needle-driving.-A curved needle 18 is carried by an arm 13 attached to a shaft 10. The opposite end of the shaft has a projecting pin 15, which has a ball-and-socket connection with the rod of an eccentric on the main shaft 9. Governing needle thread.-The thread engages with a disc tension 28 and is acted on by a take-up 29 situated between two pillars 34, through which the thread passes. The take-up is actuated by an eccentric mounted on the main shaft 9 and connected with the take-up by a rod. Feed.-The feed, which takes place in a direction perpendicular to the motion of the needle, is effected by a feed-dog, shown separately in Fig. 4. The feed-dog is contained within the cloth plate n, and consists of two bevelled plates 4, 5 carried, so as to be capable of sliding, in a plate y, and pressed upwards by springs 8, the movement being limited by a pin 7. The two sides of the feed-dog can thus be displaced independently, so as to accommodate different thicknesses of work on the two sides of the cloth plate. The plate y is pivoted at 2 to a slide 3 and is connected to a rocking arm w by a link x, the result being that the slide moves to and fro while the plate y rocks on its pivot, thus giving the required motion to the feed-dog. The arm w is rocked by a shaft r connected by a link t with an arm pivoted at f and moved by the main shaft. The connection between the link t and the arm can be adjusted so as to vary the feed. Chain stitching machines.-The luoper 20 is straight and is moved to and fro as well as oscillated by a jointed shaft 19, 24. The latter portion engages with a pin 23 on a disc on the main shaft. The pin 23 is not perpendicular to the disc so that both motions are given to the looper. The part 19 of the shaft passes through a bearing consisting of two split collars 22 screwing into taper holes in a sleeve 21 so that the collars can be adjusted for wear by screwing them into the sleeve. The looper 20 is eccentrically mounted upon, and is parallel with, the part 19 of its driving-shaft. It is oval in section, its flattened side terminating in a shoulder 26, Figs. 5 and 6, which receives the thread loop. This stage is shown in Fig. 3, in which the looper is shown advancing towards the front of the figure, and about to move to the left carrying the looper with it. In doing so, it turns, and opens the loop, assuming the position as shown in Fig. 7, which shows the loop of thread round the looper. When the feed has taken place, the plane of the loop is oblique to the plane of motion of the needle which passes through it. A groove 27 in the looper engages the thread between the needle and the work and holds it in the proper position, while the needle is passing through the loop.