JPS6112059Y2 - - Google Patents

Description

[Detailed Description of the Invention] Technical Field This invention relates to a multiple thread guide device for a double chainstitch sewing machine.

Prior Art Conventionally, in a two-needle double chainstitch sewing machine with a flat bed, a long metal plate is bent to have a substantially U-shaped cross section, as shown in Figures 1 and 2. The thread guide member 1 is fitted into a thread guide groove formed on the bed 2 so that its upper surface is flush with the upper surface 2a of the bed 2, and the thread is fed out from a thread supply source provided at the rear of the sewing machine. By inserting a plurality of lower threads 3 into the thread guide body 1, the lower threads 3 are guided to a plurality of double chainstitch loopers located below the throat plate.

However, this thread guide 1 usually has a length of about 20 cm, and when these bobbin threads 3 pass through the thread guide 1, they pass through the thread guides provided at both ends of the thread guide 1. Since the bobbin thread 3 is positioned only by the hole 4, as shown by the broken line in FIG.
may interfere with each other and become entangled inside the thread guide 1, or this interference may disturb the preset tension of the bobbin thread 3, resulting in unstable stitches. It was hot.

Purpose The purpose of this invention is to eliminate the above-mentioned drawbacks,
A double chainstitch sewing machine that prevents the bobbin thread supplied to the double chainstitch looper from tangling, stabilizes the tension of the bobbin thread, and forms uniform stitches that are well-balanced with the needle thread. To provide a multi-thread guide device.

Embodiment An embodiment embodying this invention will be described below with reference to FIGS. 3 to 6.
A pair of thread tension devices 7 are provided on the rear surface of the proximal end of the arm 6, and apply a predetermined thread tension pressure to each of the two bobbin threads 8 fed out from the thread supply source. A thread guide groove 9a is cut out on the flat bed 9 of the sewing machine frame 5 and extends from the lower position of the thread tension regulator 7 toward the throat plate 10a and cover plate 10b on the bed 9. There is a guide groove 9 inside.
A thread guide body 11 extending along a is fitted. The cover plate 10b can be opened and closed for threading a double chainstitch looper 21, which will be described later. As shown in FIG.
There is a guide plate 1 on the bed 9 corresponding to the starting end of 1.
2 is fixed, and its pair of thread guide holes 13 regulate the entry position of the lower thread 8 into the thread guide body 11.

As shown in FIGS. 4 and 5, the thread guide 11 includes a main body 14 formed by bending a long metal plate into a substantially U-shaped cross section, and side walls 1 of the main body 14.
A long plate-shaped separator 15 is erected and fixed at the center of the upper surface of the bottom wall 14b of the main body 14 so as to extend parallel to the side wall 14a between the main body 14 and both side walls 14 of the main body 14.
a long plate-shaped lid 16 fixed to the upper end of the separator 15 so as to extend substantially horizontally within the same plane as the upper edge of a;
They are fixed together by brazing or the like. Then, both side walls 14 of the lid body 16 and the main body 14
A thread insertion gap S extending along the thread guide groove 9a is provided between the thread guide groove 9a and the thread guide groove 9a. Further, a guide portion 17 is provided at one end of the main body 14 by extending the bottom wall 14b of the main body 14 and bending the tip upward, and a pair of thread guide holes 18 are provided in the guide portion 17. There is. Further, in a state where the thread guide body 11 is fitted and fixed in the thread guide groove 9a on the flat bed 9 by adhesive or the like, the upper surface of the lid body 16 and the main body 1
The upper ends of both side walls 14a of the bed 9 are flush with the upper surface of the bed 9.

The two bobbin threads 8 that have passed through the thread guide hole 13 of the guide plate 12 are passed separately through both sides of the separator 15 in the thread guide body 11, and are passed through the thread guide hole 18 of the guide portion 17. After its derivation position is regulated,
The threads are guided through the bobbin thread take-up 20 to two double chainstitch loopers 21 located below the throat plate 10 and attached to one looper main body 21a. The bobbin thread take-up 20 includes a cam body 20a that rotates with the rotation of a lower shaft (not shown) provided in the sewing machine frame 5, and a pair of cam bodies that press the bobbin thread 8 against the outer cam surface of the cam body 20a. This is a well-known type consisting of a fixed guide 20b, and the bobbin thread 8 is picked up from the looper 21 side by the cam action of the cam body 20a.

Now, in a sewing machine equipped with a plurality of thread guide devices configured in this way, the position of the two bobbin threads 8 is regulated by the thread guide holes 13 and 18 at both ends of the thread guide body 11, and the thread guide body 11 Inside, each bobbin thread 8 is guided along an independent path by the separator 15, so that when the bobbin thread 8 passes through the thread guide body 11, there is no interference or entanglement with each other. Further, the rough inner surface of the thread guide groove 9a formed on the bed 9 is connected to the thread guide member 1.
1, the lower thread 8 passing through the thread guide body 11 does not come into direct contact with the inner surface of the thread guide groove 9a. There is no risk of wear or thread breakage.

Therefore, the lower thread 8 leading to the looper 21 does not become tangled due to interference with the lower thread 8 as in the conventional example, and no excess tension is applied to the lower thread 8. Instead, only the tension preset by the thread tensioner 7 acts on the lower thread 8, thereby forming a uniform and stable stitch that is well balanced with the upper thread.

In the above embodiment, the separating body 15 that divides the inside of the main body 14 of the thread guide 11 into two at the center is one.
In this case, the lid 16 is fixed to the upper end of the main body 14 so that the two bobbin threads 8 can be guided independently. It is also possible to configure the thread guide body 11 that can independently guide the bobbin thread 8.

Effects As mentioned above, this invention has a sewing machine bed of 9.
A thread guide groove 9a is provided on the top, and a separator 15 is provided between the thread guide groove 9a and the lid 16 to guide a plurality of bobbin threads 8 independently. 8 from interfering and getting entangled,
Moreover, it is possible to eliminate the cause of instability of the bobbin thread tension due to such interference, and it is possible to always stabilize the tension of the bobbin thread 8 and form uniform and beautiful stitches that are well-balanced with the needle thread. It has a great effect.

[Brief explanation of the drawing]

Fig. 1 is a perspective view showing a conventional example related to this invention, Fig. 2 is a sectional view thereof, Fig. 3 is a perspective view of a double chainstitch sewing machine related to this invention, and Fig. 4 is a perspective view of a conventional example of this invention. FIG. 5 is a perspective view showing the thread guide of the embodiment, FIG. 5 is a sectional view showing the thread guide fitted in the bed, and FIG. 6 is a schematic diagram showing the path of the bobbin thread. Sewing machine frame...5, flat bed...9, thread guide groove...9a, thread guide body...11, separation body...1
5. Lid body...16. Looper...21. Thread insertion gap...S.

Claims (1)

[Claims for Utility Model Registration] A thread guide groove 9a formed in a notch on the bed 9 of the sewing machine and for accommodating a plurality of threads 8 extending from a thread supply source to a plurality of double chainstitch loopers 21; It is arranged in the thread guide groove 9a so as to be substantially flush with the upper surface of the bed 9 and to extend along the thread guide groove 9a, and between both side walls of the thread guide groove 9a. Lid bodies 1 each forming a thread insertion gap S extending along the
6, and a separator 15 provided between the lid 16 and the bottom wall of the thread guide groove 9a to prevent the plurality of threads 8a from coming into direct contact with each other and becoming entangled. A multiple thread guide device for a double chainstitch sewing machine featuring: