JPS5849753Y2 - sewing machine - Google Patents

Description

[Detailed description of the invention] The present invention relates to a sewing machine, and more particularly to a sewing machine that can be used for lock stitching and chain gutter by simply inserting and removing a single attachment member in place of the bobbin thread bobbin in the sewing machine hook. Regarding.

In the following, an embodiment of the present invention will be explained.
is the throat plate of the sewing machine, 2 is the feed dog window provided on the throat plate to make the feed dog 9 (Fig. 2) perform the so-called four movements, 3 is the needle hole, and 4
6 is a sewing machine needle that carries the upper thread 5 and makes a vertical reciprocating movement through the needle hole 3; 6 is a sewing machine needle that is connected to the needle plate near the lower part of the vertical reciprocating area of the needle 4 and in keeping with the movement timing; 1
A roughly bowl-shaped horizontal full-rotation type thread ring catcher 76 rotates below (arrow R), and is always supported stationary within the catcher 6 and houses a bobbin for bobbin thread (not shown). A chain gutter attachment (72) which is freely attached to the inner hook 7 (Fig. 2-a) and can be freely inserted and removed in the vertical direction in place of the bobbin for the bobbin thread
'(Fig. 2-b) shows the free end of the thread ring guide piece 75 extending beyond the upper surface of the inner hook 7 and protruding generally toward the needle hole 3; Inner wall surface 71 of a bobbin storage cylindrical chamber provided for storing a bobbin for bobbin thread
It is a shallow vertical groove carved almost vertically at the right place,
Reference numeral 74 is provided with a short length projecting at an appropriate position on the cylindrical portion of the gutter attachment main body 72', and when inserting the rear attachment 72' into the inner hook 7, it fits into the vertical groove 73 and positions the attachment. It is a protruding pin.

Reference numeral 8 denotes a thread ring engagement/disengagement control edge 81 provided at the front end and having a length suitably larger in the left and right direction than the center W of the guide piece 75 on the left and right sides.
(Fig. 1) moves back and forth between an advanced position F under the back surface of the thread ring guide piece 75 and a retracted position B sufficiently far back from the position close to the needle movement locus. The thread wheel control piece 83 in FIG. together with the rotating shaft 61 of the sewing machine.
A control piece rocking lever 86 which abuts from the rear on a vibration generating cam 65 provided at the rear and is biased by a spring 85 is a relatively weak spring that tends to bias the control piece 8 upward.

Below, we will first explain the case where the sewing machine is used with the attachment 72' inserted in place of the bobbin for bobbin thread.
In Fig. 1, 51 is a chain gutter seam that is completely bordered on the fabric to be sewn (not shown), and 52 is reduced by the action of a sewing machine thread take-up mechanism (not shown) after surrounding the inner pot 7. The guide piece 75 reaches the top of the thread ring guide piece 75 while being moved, but due to the relationship with the thread ring control piece 8 which is in the advanced position F as shown in the figures (Fig. A thread ring 5 is held at the top with sufficient expansion corresponding to the above-mentioned width W.
3 is the left and right thread leg T1. A new thread ring 5 newly formed near the needle tip when the needle 4 descends and then rises during T2.
4 (Fig. 1-b) is captured by the yarn ring catcher 6, the control piece 8 is swung to the retracted position B and released from the moored state 53' (Fig. 1-c). ,
Furthermore, the chain gutter stitch is completed when it is further reduced to the limit where it contacts the lower surface of the fabric to be sewn, and the above-mentioned movable members, such as the needle 4, thread loop catcher 6, thread loop control piece 8, etc., perform synchronous related operations. By the time the stitch 52 is completed, the needle 4, which has formed the new thread loop 54, rises to a position above the throat plate 1, and the thread loop catcher 6 also rotates synchronously. The thread ring 54 is enlarged until it completely surrounds the inner hook 7 through the state 53' of FIG. After that, the thread loop 54 is made to follow the same process as described above for the thread loop 53, and the chain trough stitches are continued.

It should be noted that the cloth feeding method for carrying out the above-mentioned kinship does not necessarily have to use the throat plate 1 and the feeding dog 9.

Next, when the attachment 72' is removed, the bobbin for the bobbin thread can be installed in the inner hook 7 in the conventional manner, so that a normal lock stitch edge can be formed.

In addition, in this edge, the thread ring engagement/disengagement control edge 81 is the third
As shown in the figure, since the movement of the edge 81 follows the vertical moment of the movement of the cloth feed dog 9, the movement of the edge 81 acts on the bobbin thread 7' in a timely manner, and has the effect of assisting in tightening the thread in the lock stitch. It is something that will be added.

As described above, the present invention makes slight improvements to the sewing machine for lock sewing edges, thereby creating a sewing machine that can be adapted to both lock sewing and chain troughs by simply operating the attachments. This is a device with great practical effects, such as improved thread tension.

[Brief explanation of drawings]

The drawings show an embodiment of the present invention, in which Fig. 1-a shows the contact relationship between the thread wheel control piece and the guide piece, Fig. 1-b shows the catching state of a new thread ring by the thread ring catcher, and Fig. Figure 1-0 shows the detachment relationship between the thread wheel control piece and the guide piece, Figure 2-a is a perspective view of the main parts of this sewing machine in a state where chain trough operation is performed, and Figure 2-b shows the chain trough attachment part. Slope view with the chisel removed, Figure 3a
, l), c, and d are explanatory diagrams using sectional views showing the lock sewing state step by step by the sewing machine of the present invention, and FIG. 4 is a sectional view showing a similar state step by step. In the figure, 1 is the throat plate, 3 is the needle hole, 4 is the sewing machine needle, 5 is the needle thread,
54 is an upper thread ring, 6 is a thread ring catcher, 7 is an inner pot, 72' is a chain trough attachment, 75 is a thread ring guide, 76 is a free end, 8
81 is a thread wheel control piece, and 81 is a control edge.

Claims (1)

[Scope of utility model registration request] A sewing machine needle 4 carrying an upper thread 5 and moving up and down through the needle hole 3 of the needle plate 1 in synchronization with the rotation of the sewing machine, and an upper thread ring provided below the needle plate 1 and formed by the needle movement. 54; and an inner lid 7 configured to accommodate a bobbin for the bobbin thread and substantially stationary within the bobbin thread catcher. It is an attachment that can be freely inserted into and removed from the inner lid 7 above and below in place of the bobbin, and when it is attached to the inner pot 7, the free end 7
a chain gutter attachment 72' in which a wide thread ring guide piece 75 is disposed on the upper surface of the inner hook so that the thread ring 6 is generally directed toward the needle hole, and the guide piece extends laterally from the front end. An advanced position F in which the thread ring disengagement control edge 81, which has a width greater than 75, is under the back surface of the guide piece and a retreat close to the movement trajectory of the needle sufficiently far back from this position. A sewing machine comprising a thread wheel control piece 8 arranged to move back and forth between a position B and a mechanism for reciprocating the control edge 81 in synchronization with the rotation of the sewing machine.