JPH0317835Y2 - - Google Patents

Description

[Detailed description of the invention] Purpose of the invention (industrial application field) This invention consists of a support case that is supported in a horizontally movable manner at the end of a sewing machine arm, and a plurality of needle bars each having a needle at the lower end, and each needle bar. A plurality of thread take-up bodies respectively corresponding to the needle bars are vertically movably supported, and as the support case moves laterally, the needle bars and thread take-up threads corresponding to each other are sequentially arranged at the sewing position, whereby the needle thread is switched. This invention relates to a multi-needle sewing machine that performs sewing.

(Prior Art) In a conventional multi-needle sewing machine of this type, a needle bar supports a plurality of thread tension devices for applying tension to threads from a plurality of thread supply sources to each thread take-up body and the eye of the needle. It was fixedly mounted on the sewing machine frame above the support case.

(Problem to be Solved by the Invention) Therefore, in this conventional multi-needle sewing machine, as the support case for changing the upper thread moves, the distance between each thread tension device and the corresponding needle eyelet increases. When the length of the thread path changes and the thread path becomes shorter, slack will occur in the needle thread between the thread tension device and the eye hole, and when sewing is performed with this needle thread, the slack will be removed. Until it is absorbed, the thread cannot be tightened properly, resulting in the formation of stitches with poor thread tightness. In addition, the thread tension device clamps the upper thread with a predetermined pressure, and
When switching the needle thread, the needle thread is cut below the eye hole, so if the thread path becomes longer due to movement of the support case, there is a risk that the needle thread will be pulled out from the eye hole of the needle due to movement of the support case. There is. Therefore,
Conventional multi-needle sewing machines are equipped with a thread gripping device that grips the cut upper thread to prevent it from pulling out from the eye of the needle, which not only complicates the construction, but also When sewing is performed by returning the needle bar support case in the direction in which the thread path becomes shorter, the thread loosens, which adversely affects thread tightness, as in the case described above.

Furthermore, in conventional sewing machines, the thread tension device is located above the support case, so the thread path becomes quite long even when it is at its shortest, which increases the elongation of the thread and causes the thread to tighten as described above. It had a negative impact.

Structure of the invention (Means for solving the problems) In order to solve the above problems, this invention uses a plurality of thread tension devices in each thread take-up to apply tension to the thread from the thread supply source to the thread take-up. It is provided on the support case so as to correspond to the body.

(Function) Therefore, the thread path between each thread take-up body and the eye of the needle is always maintained at the same length, making it possible to always obtain stitches with good thread tightness, and eliminating the need for a thread gripping device. Easy to configure.

(Example) Hereinafter, an example that embodies this invention will be described based on the drawings. As shown in FIG. 1, a sewing machine frame 1 includes a bed 2 and an arm 3 erected on the bed 2. As shown in FIG.

As shown in FIG. 3, a sewing machine main shaft 4 is supported within the arm 3 and is rotated by a drive source (not shown). Further, as shown in FIGS. 3 and 4, two rotating shafts 5 and 6 extending vertically are rotatably supported at the tip of the arm 3, and two rotating shafts 5 and 6 are rotatably supported at both upper and lower ends of one rotating shaft 5. Pinions 7 are each fixed. A reversible drive motor 8 is fixed to the upper surface of the arm 3, and a gear 9 on the motor shaft meshes with the upper pinion 7, and the drive motor rotates the rotating shaft 5 in both forward and reverse directions. .
A lower elevating body 10 and an upper elevating body 11 as driving means are supported between the rotating shafts 5 and 6, and the lower elevating body 10 and the sewing machine main shaft 4 are connected via a crank mechanism 12. Further, another shaft (not shown) connected to the sewing machine main shaft 4 via a gear mechanism 13 and the upper elevating body 11 are connected via another crank mechanism 14, and the upper elevating member 11 also connects to the sewing machine main shaft 4. Due to the rotation, the lower elevating body 10 is moved up and down at different timings.

A needle bar support case 17 is movably supported at the tip of the arm 3 by engagement of guide surfaces 15 and 16, and a total of six needle bars 18 are movable up and down in the needle bar support case 17. supported, they are equipped with a needle 38 at their lower end. A connecting pin 19 is fixed to each needle bar 18 . Further, a thread take-up body 20 is fitted and supported in each needle bar 18 so as to be movable up and down, and each thread take-up body 20 is attached to the face plate 2 of the needle bar support case 17.
It projects forward through a vertical groove 22 formed in 1, and a thread insertion hole 23 is provided in the protrusion. A connecting pin 24 that projects rearward is fixed to each balance body 20. Each needle bar 18 supports a presser foot 26 which is urged downward by a spring 25 so as to be movable up and down.

As shown in FIG. 4, both the connecting pins 19 and 24 are fitted into lower and upper grooves 27 and 28 formed on the front surface of the arm 3, respectively.
Due to the lateral movement of the needle bar support case 17 when the sewing machine is stopped, the connecting pins 19 and 24 are moved by the grooves 27 and 28 to the lower and upper elevating bodies 10 and 1.
The lower elevating body 10, the needle bar 18, and the upper elevating body are moved to a position where they are held by the pin holding parts 29 and 30 of No. 1, and the lower elevating body 10, the needle bar 18, and the upper elevating body are The body 11 and the take-up body 20 are connected, and the rotation of the sewing machine main shaft 4 causes the needle bar 18 and the take-up body 20 to move up and down.

The face plate 2 corresponds to each balance body 20.
A thread tension device 31 is fixedly attached to the upper end of the thread tension device 1, and each of the thread tension devices 31 is provided with a pair of thread tension discs 32.

A thread stand 33 is fixed to the upper part of the arm 3,
A thread guide 34 is provided on the top surface of each thread tension device 31.
An upper thread bobbin 35 is installed, with an upper thread 36 guided therethrough. Note that the upper thread 3 is located at the bottom of the face plate 21.
thread guide 37 for guiding the thread 6 to the eye hole 39 of the needle;
is fixed.

Now, during sewing, the needle bar 18 and the thread take-up body 20 connected to the lower elevating body 10 and the upper elevating body 11 are moved up and down, respectively, and the needle 3 at the lower end of the needle bar 18 is moved up and down.
Sewing is performed using the upper thread 36 supplied to the thread take-up body 20 on the needle bar 18 by 8. and,
When switching threads, sewing is temporarily stopped and the upper thread 36 that has been sewn up to that point is cut by a thread cutting device (not shown). Subsequently, the needle bar support case 17 is laterally moved so that the thread take-up body 20 and the needle bar 18, to which the required needle thread 36 has been supplied, are connected to the upper elevating body 11 and the lower elevating body 10, respectively.

In this case, in this sewing machine, the thread tension device 31
are supported on the needle bar support case 17 so as to correspond to each needle bar 18 and the thread take-up body 20, so that the distance between the thread tension device 31, the thread take-up body 20, and the eye hole 39 of the needle 38, that is, the thread Adjuster 31 and the eye hole 39
The length of the thread path between the two is always constant. Therefore, even if the needle bar support case 17 moves, the upper thread 36 will not become loose or fall out of the eye hole 39. Moreover, the thread path can be shortened, the elongation of the thread can be reduced, and the thread is always A well-tight seam can be obtained. Further, a thread gripping device for preventing the thread from coming out from the eye hole 39 is not required.

Effects of the invention As exemplified in the embodiments above, in this invention, by providing a thread tension device on the support case so as to correspond to each thread take-up body, it is possible to always obtain good stitches with uniform tightness. Moreover, a thread gripping device is not required, and the structure can be simplified, which is an excellent effect.

[Brief explanation of the drawing]

Figure 1 is a side view of a sewing machine embodying this idea, Figure 2 is a front view, Figure 3 is a sectional view of the main parts, and Figure 4 is a front view showing the connection structure of the needle bar and thread take-up body. be. 3... Arm, 4... Sewing machine main shaft, 10... Lower elevating body, 17... Needle bar support case, 18... Needle bar, 20... Take-up body, 23... Thread insertion hole, 31...
...Thread tension device, 38... Needle, 39... Eye hole.

Claims (1)

[Claims for Utility Model Registration] A support case 17 supported laterally on the end of an arm 3 of a sewing machine has a plurality of needle bars 18 each having a needle 38 at its lower end, and a plurality of needle bars 18 corresponding to each needle bar 18. A plurality of thread take-up bodies 2 each having a thread insertion hole 23 for passing the thread guided into the eye hole 39 of the needle 38.
0 movably up and down, and the supporting case 17
The needle bar 18 and the balance body 2 correspond to each other as the
In a multi-needle sewing machine in which needles 0 and 0 are sequentially arranged at a sewing position and are connected to a driving means 10 at that position to perform sewing, A plurality of thread tension devices 31 are connected to each thread take-up body 2.
A thread tension device characterized in that the thread tension device is provided on the support case 17 so as to correspond to the thread tension device 0.