DE60034C - Hook sewing machine for lockstitch and chain stitch - Google Patents

Description

IMPERIAL

PATENT OFFICE.

CLASS 52: Sewing machines.

The present invention relates to a lockstitch looper sewing machine with which not only lockstitch, but also chain stitch can be produced. to for this purpose the sewing machine is equipped with a reciprocating loop holder, which is brought into working position when a chain stitch seam is formed and the Thread loop lifts from the loop former, it expands and expands into one for the passage of the needle at its next decline transferred to a suitable position.

Fig. Ι shows the end view of the necessary to explain the invention part of a Gripper sewing machine, Fig. 2 the view of this part of the machine, seen from below. Fig. 3, 3 a, 3 b, 4, 4 a, 4 b, 5, 5 a, and 5 b show three different positions of the working parts when chain stitch seams are formed.

A is the work surface of the machine, D the rotating hook, which here takes the place of the shuttle in lockstitch - shuttle - sewing machines. Said gripper is inserted into a circular guide and is set in rotation by a shaft D ^{1 in the manner customary in such gripper sewing machines.} The spool of yarn can either be removed from the gripper or remain in the gripper when a chain stitch seam is formed, in which latter case the thread has to be cut off briefly.

E is the reciprocating loop holder, the general shape of which can be seen in FIG. 4b, and which consists of a plate with fork E ¹ and the laterally outwardly projecting projections or horns E ² at the front end; at the rear end the plate has a hollow attachment E ^s . The shape of this loop holder can be changed slightly as required.

Fork E ¹ is intended to enter the loop formed by the looper hook D , to present the latter expanded for the next descent of the needle and thereby to form a chain stitch seam.

The back and forth movement of the loop holder is caused by the pin / which engages in the attachment E ^s on the loop holder E.

With gripper sewing machines, the loop holder does not need, as with shuttle sewing machines It is necessary to impart a swinging motion and a straight back and forth motion, as in the shuttle sewing machines the loop through the shuttle or the organ effecting the widening of the loop completely is pulled on one side of the needle; by now the extended one for shuttle sewing machines To present the loop of the needle, of course, the loop holder with the one on it must lying loop to the side.

In hook sewing machines the loop is widened so that it extends on both sides of the extends perpendicular axis of the needle; consequently, the loop holder can be in a Move the plane back and forth with the needle and there is no need to move sideways.

If necessary, the loop holder can be given an oscillating movement which can be caused in a known manner. In the aforementioned approach E ³ on the plate E engages a pin / on a collar or

Ring Z with connecting arm Z " ¹ is seated; said collar is pushed loosely onto an outer tube Y , which in turn is also loosely pushed onto shaft X. Shaft X lifts the knife valve F in the usual way and does not form part of the present invention The arm Z ¹ is supported by the resilient pin χ serving as an insert, which, if necessary, connects the ring Z with the upper tube X ; the latter is connected to the shaft D ¹ by an arm V and a connecting rod V ¹ from an eccentric T on the shaft D 1 The loop holder E is therefore actuated by the eccentric T in such a way that the loop holder E stands still in the outermost position, while it moves relatively quickly in another part of its movement.

On the underside of the needle plate sits a short plate ^ which is arranged close to the needle hole and parallel to the direction of movement of the loop holder E , the thread loop during thread take-up between the horns or projections i? ² so that the slack lying thread does not slide off the fork E ¹ and creates an imperfect stitch. For the safe entry of the holder E into the thread loop, a small metal strip D * is attached to the side of the gripper D , which extends the upper part of the thread loop to a lesser extent.

If the lockstitch sewing machine is now to be converted into a chain stitch sewing machine, the insert χ only needs to be shifted so that it connects the ring Z with the upper tube Y , whereupon the thread reel is removed from the hook or the thread just before the The thread spool cuts off. In order to convert the chain stitch sewing machine into a lockstitch machine, it is only necessary to move the loop holder to its rearmost position and then to withdraw the insert χ , whereby the cover tube alone performs a rocking movement without the ring Z carrying the pin f rotating with it; Finally, just insert the thread spool.

The advantages of the present invention are that the machine forms a self-contained whole, the attachment of interchangeable parts to change the type of stitch is avoided, and that apart from the connection and separation of parts Y and Z only the spool of thread is taken out and reinserted which, however, has to be repeated almost every hour by the seamstresses, and is therefore fairly familiar to them.

Claims (2)

Patent Claims: ι. A lockstitch looper sewing machine, which can be converted into a chain stitch sewing machine by activating a plate-shaped loop holder (E) arranged in the machine, which at its front end has two lateral projections or horns in addition to a fork (E ² ) and with its back and forth movement alternately enters the loop extended by the hook, presents the latter to the needle descending on it and is returned to its starting position in a straight (or sideways) movement, with one attached below the needle plate, in The plate (\) lying on the loop holder web can be arranged, which holds the loop between said horns while the thread is being picked up and prevents the slack thread from sliding off the fork (E). 2. To actuation and Aufserbetriebstellung the in claim ι. The above-mentioned loop holder is the arrangement of an eccentric (T) on a shaft (D ¹ ) of an overpipe (Y) set in rocking motion by the same and loosely pushed over the knife shaft and a ring (Z) loosely pushed over the latter and carrying the slift for driving the loop holder - which for the temporary movement of the loop holder can be temporarily connected to the above-mentioned cover tube by means of a resilient insert pin (x). For this purpose i sheet of drawings.