JPS58357B2 - Sewing method and sewing machine - Google Patents

Description

[Detailed description of the invention] The present invention relates to a method for performing undulating stitches using a sewing machine.

The invention also covers a sewing machine fitted with a special needle for carrying out the method.

As is well known, a wavy stitch is sewn along the edge of a fabric and is formed by a single sewing thread cut to a predetermined length (so-called "-out-of-line"); Appears alternately on the front and back sides.

However, this type of stitching, which can only be done by hand, is usually used for decorative purposes, especially on lapels, pockets, etc. of ready-to-wear clothing, and is also used to finish trousers, handbags, gloves, and similar items. .

However, such manual work is an obstacle to the industrial production of ready-made clothing, given current sewing technology.

The main object of the present invention is to make it possible to perform such stitches with decorative features by machine, in order to meet the industrial manufacturing requirements of ready-made garments.

The method of mechanically creating wavy stitches according to the present invention is that in the first cycle of the needle moving up and down, the thread is threaded down the fabric by the same needle, removed from the needle and left there, and then The whole is moved into place and left there to form the lower stitches, during which the fabric is fed.

Furthermore, the essential feature is that in the second cycle this thread is again passed onto the needle and passed over the top of the fabric, left there to make the upper stitch and then the fabric is fed.

A sewing machine according to the invention implementing a novel method of machine sewing comprises a needle with an open needle hole that allows thread to be threaded onto and removed from the same needle;
A thread hook device (thread h) is located on the underside of the fabric and is used to remove the thread from the needle and pull all the remaining thread under the fabric to hold it there.
looking up devi-ces); also on the underside of the fabric for hooking the thread onto the needle again; and on the top of the fabric for guiding the thread and keeping the volume system through which the fabric is fed into the open needle hole. oscillating hook; all such devices are controlled by a cam driven by the upper shaft of the sewing machine, and the transition of these devices from the inactive state to the working state and vice versa is in reverse order. It is characterized in that it is performed in synchronization with the operating cycle of the sewing machine.

Furthermore, in detail, the inner loop of the open needle hole of the needle has a double hook shape so that the thread can be hung and moved when the needle moves in either the up or down direction. The needle tip is asymmetrically shaped to prevent the fabric from entering the open needle hole as the needle moves up or down through the fabric.

Thread hook device on the underside of the fabric
king-up devices) consist of a disk rotating about a substantially horizontal axis, the disk being offset slightly rearward from the stroke plane of the needle;
Each reciprocation of the needle makes one rotation (360°).

At the outer edge of the disc there is a hook, so that one side of the thread loop carried by the needle cooperates with a pick-up hook and a thread tension holder located in front of the disc in each second cycle to control the rotational movement of the disc. In between, prepare the thread for the next stitch and pull it out (this is equivalent to pulling the thread when the needle passes through the fabric when sewing by hand; this operation supplies the thread for the next stitch) The pink amplifier hook and thread tension holder engage with the other side of the thread loop, making one reciprocation on the horizontal plane for every two reciprocations of the needle.

The thread tension holding member, which makes one reciprocation on the horizontal plane every two working cycles, cooperates with a fork-shaped member, which swings to pick up the thread and convey it to the open needle hole, and as the needle rises. Insert into the open needle hole.

The upper swinging hook makes one reciprocation every two actuation cycles.

Further features and advantages of a sewing machine equipped with a special needle implementing the undulating method according to the invention will become apparent from the following description of a preferred embodiment and from the drawings.

These descriptions and drawings are a non-limiting example.

In the accompanying drawings, in particular FIGS. 1 and 2 (standard components of a conventional sewing machine are omitted or not shown) 1
1 is a needle plate, 1' is a bed with an arm 2 in which there is a presser foot 3 for the fabric or fabric 4 to be sewn, a special needle 5 and a sewing hook 6.

Under the bed 1' there is a device designed to cooperate with a special needle 5 for undulating stitches, which device is driven by a hand wheel via shafts 8, 9, 9', and is connected to the lower shaft. 8 is keyed with a disc 10, which disc is offset slightly rearward from the stroke plane of the needle, while
Cams 15 and 17, which control the thread take-up 12 and thread tension temporary presser 14, respectively, are driven by shafts 9 and 9'.

As can be seen from the detailed cross-sections shown in FIGS. 3 and 4, the swing hook 6 is located laterally and rearward of the needle, and is pivoted on the hook 6' so that it swings back and forth in the sewing machine as the cam 11 moves. (See Figure 3).

In relation to the needle 5, the hook 6 thus assumes the limit position shown in FIG. 3 by solid and broken lines.

The cam 11 is connected to the shaft ii″′ connected to the hand wheel 7.
through gears 11' and 11''.

A thread take-up 12 located under the bed 1' and close to the movement of the needle 5;
The hook 13 and the thread tension temporary press 14 are all attached to the disk 10.
is located in front of.

As can be seen from the detailed view in FIG.
5 is controlled by a shaft 9 via suitable coupling means.

A hawk-shaped member 16 pivoted at 16' is connected to the rod 12'.
The needle 5 swings around the needle 5.

The function of the thread take-up 12 is to pick up the thread and, during the working process, bring it around the needle 5 and place it into the open needle hole of the needle for rehanging the thread.

The hook 13 slides back and forth on a horizontal surface and is connected to a thread tension temporary press 14, which in turn is connected to a cam 17.
The cam 17 is controlled by the shaft 9' via suitable coupling and transmission means (see FIG. 4).

The function of the hook 13 is to catch the sewing thread under the fabric, and it operates in conjunction with the thread tension holder, while the thread tension plate holder presses the sewing thread with its flute 14' against the fixing stop 14'' and does not move. do it like this.

As shown in detail in FIG. 5, there is a hook 18 on the edge of the disc 10 which catches the thread on the underside of the fabric and, by rotation of the disc 10, pulls the thread out in preparation for the next stitch.

A stationary disk 19 provided with a circumferential groove 20 is coaxial with the disk 10, and the thread pulled out by the rotating disk 10 in preparation for the next stitch enters the circumferential groove.

21 is a feed dog that feeds the fabric during sewing, and is located directly below the throat plate 1.

As shown in FIGS. 1 and 8, the needle has an open needle hole 5' with an asymmetrical tip and a double hook-shaped inner contour.

The transmission ratios are determined so that the components of the sewing machine operate in the required order and orderly.

In particular, one "cycle" consists of one round trip of the needle and the feeding of the fabric.
Then, the knee swing hook 6 swings in each second cycle.

- the thread take-up 12 is activated in each second cycle;

- the hook 13 swings alternately in each first cycle in opposition to the movement of the thread take-up 12;

- The thread tension holder 14 is actuated in each first cycle in accordance with the movement of the hook 13, and is not actuated while the thread take-up 12 is moved to rehang the sewing thread onto the needle.

One disk 10 makes one revolution (360°) in each cycle, but the sewing thread hooks 18 in each first cycle.
It takes.

The sewing machine operates as follows to perform wavy stitching.

The standard sewing thread, which is usually wound around a spool, is unwound by a stitcher, passed through a thread tensioner, and then cut the thread (this device itself is not shown because it is of a common type).

) and then passed through the open hole of the sewing needle 5 for final sewing.

After sewing a few stitches with the sewing machine, use the thread cutter to cut the sewing thread to the length of one stitch.

In order to prevent the sewing thread from falling out when sewing, the sewing thread before being cut with the thread trimmer should be properly secured between the needle and the preset, and the sewing thread after being cut with the thread trimmer should be held at the cut end. Fasten it to an arm, bed, etc. in an appropriate manner.

The sewing machine is started and the needle 5 carries the thread with it through the fabric 4 until it reaches its bottom.

As the needle begins to rise, a loop of thread is formed, and the loop catches onto the rotating disc 10.

The thread is removed from the needle by the disc 10, and as the disc rotates the entire system, except for one needle, is pulled down under the fabric.

The needle 5 is raised without thread and the needle 5 is removed from the fabric 4.

The fabric is then fed, creating a length of stitching that appears on the underside of the fabric.

As soon as the feeding of the fabric is finished, the needle begins to descend through the fabric without thread.

Then, when the thread begins to rise next time, the thread left on the underside of the fabric is caught in the needle hole with the help of the thread taker 12, passed through the fabric, and carried to the upper side.

Once the needle has finished rising, the fabric is fed again and the upper stitch length of the fabric is completed.

The needle then begins its next descent through the fabric with the thread, thus beginning the next cycle.

The resulting seam is shown in Figure 9.

The sequence of operating steps of some sewing devices is shown in the accompanying figures or as follows.

1.-Start of sewing: The thread is introduced into the needle hole 5' of the needle 5 which is above the fabric.

All devices are inactive and none are engaged with the suture.

In particular, the disk 100 hook 18 is located approximately on the opposite side of the needle 5 from the center of the disk (see FIGS. 3 and 4).

2, - 1st cycle (see figures 10, 10A, 11, 11A).

By lowering the needle 5, the thread passes through the fabric.

The disk rotates 180° so that its hook 18 is at a very small distance from the needle.

The hook 13 and the plate 14' of the thread tension holder 14 move forward and come into contact with the movement of the thread.

The needle 5 begins to rise and the thread is no longer pulled by the needle, forming a loop of thread.

The loop hangs on the hook 18 of the disc 10, and as the disc rotates, the hook is brought into alignment with the centerline of the needle.

The needle 5 is raised completely without thread, the hook 13 and the plate 14' of the thread tension retainer 14 move back to catch the thread, while the disc 10 rotates a further 180°.

Thereby, the thread is prepared for the next stitch and the remaining length of its outer section is drawn down onto the underside of the fabric and into the circumferential groove 20 of the fixing disk 21 (see FIG. 4).

After the needle 5 has been raised without thread, the fabric is fed by the feed dog 21, thereby creating a stitch length on the lower side of the fabric.

3.-Second cycle (see figures 12, 12A, 13, 13A).

After the fabric has been fed, the threadless descent of the needle ends, while the swinging hook 6 is swung forward.

Then, the thread take-up 12 moves forward and the thread is carried in front of the needle 5.

The disk 10 is rotated 180 DEG and its hook 18 is located on the upper side of the disk, ie on the needle side as seen from the center of the disk.

When the needle 5 begins to rise, the thread is hung through the needle hole and carried onto the fabric 4.

When the needle 5 is fully raised, the thread take-up 12 returns to the starting position and the disk 10 rotates a further 180°.

When the needle 5 moves down a little to loosen the thread, a loop of thread is created.
Hook 6 hooks the ring and returns to the starting position.

The fabric 4 is fed by the feed dog 21 to create a stitch length on the upper side of the fabric.

The above cycle is repeated in the same order, but the difference between the first cycle and the subsequent cycles is that in subsequent cycles the remaining threads on the underside of the fabric are prepared for the next stitch and the hook of the disc 10 is The only point is that the pulling down of the fabric by 18 to the underside again takes place with the intervention of the hook 6.

That is, - while the entire length of the remaining yarn of the outer portion is hung on the swinging hook, the Dinuk 10 is moved as shown in FIGS.
is pulled down to the underside of the fabric by the rotation of the

At this time, the movement of the remaining thread of the -outer part along its entire length can be explained by the movement of its free end.
0 hook 18 and is finally pulled down to the underside of the fabric again.

The swinging hook 6 thus ensures that the remainder of the sewing thread on the underside of the fabric is raised above the fabric and finally pulled down again under the fabric, without getting entangled in the fabric. Helpful.

[Brief explanation of the drawing]

FIG. 1 is a schematic side view of a sewing machine with a special needle according to the present invention. FIG. 2 is a schematic front view seen from the left side of FIG. 1. FIG. 3 is an enlarged sectional view taken along the line ■-■ in FIG. 1. FIG. 4 is a sectional view taken along the line ■--■ in FIG. 3. FIG. 5 is a sectional view taken along the line ■--■ in FIG. 3. FIG. 6 is a plan view taken along the line ■--■ in FIG. 4. 7 and 8 are an enlarged front view and a side view, respectively, of the tip of the sewing needle. FIG. 9 is a diagram showing the form of wavy stitching. 10 to 14 schematically show the positions of the sewing elements in different cycles, respectively. Specifically, FIGS. 10 and 10A show the downward stroke of the needle at the beginning of sewing in the first cycle, FIGS. 11 and 11A show the upward stroke of the needle in the first cycle, and FIGS. Figure 12A shows the downward stroke of the needle in the second cycle, Figures 13 and 13A show the upward stroke of the needle in the second cycle, and Figures 14 and 14A show the downward stroke of the needle in the first cycle after the second cycle. FIG. 1... Throat plate, 1'... Bed, 4...
...Texture, 5...Needle, 5'...Open needle hole, 6...Swivel hook, 10...
Rotating disk, 12... Thread take-up, 13...
...Hook, 14...Thread tension temporary presser, 14
′... Plate, 16... Fork type member, 18... Hook, 19... Fixed disk, 20... Circumferential groove.

Claims (1)

[Scope of Claims] 1 In the vertical movement cycle of the needle, in the first cycle, the needle with the thread one stitch beyond the open needle hole passes through the fabric with the thread still attached, and then descends below the fabric. The hook of the rotating disc on the underside of the fabric catches the loop of the thread and removes the thread from the needle hole, pulling down all the remaining thread from the first stitch down to the underside of the fabric and leaving it there. The needle rises until it leaves the fabric without thread, and then the fabric moves forward by one length; then in the second cycle, the needle without thread passes through the fabric again and descends below the fabric, and the needle rises again. When you start, the thread that was left on the underside is hooked again into the open hole of the needle, and the needle moves up until it leaves the fabric with the thread, and then the fabric moves forward one space and the oscillating hook on the top of the fabric hooks up. A method of mechanically producing wavy stitches by engaging a loop of thread; and subsequently repeating the operating cycle described above. 2. A needle with an open needle hole, perpendicularly intersecting the bed in the up-down direction, with which the thread can be hooked and unloaded on the same needle: a needle with an open needle hole, arranged on the underside of the fabric, for unhooking the yarn from the needle, and with which the fabric is fed. A hook-type member for pulling down all remaining threads outside the needle to the underside of the fabric and leaving them there while the needle is being raised across the fabric; A thread taker that slides back and forth on a horizontal plane on the underside of the fabric to hang it in the needle hole; it is located on the underside of the fabric and has a hook around its periphery, and as it rotates, the hook hooks the thread, and the thread is moved down the fabric. a disk that is retractable to a swinging hook for guiding said thread while it is fed and leaving it intact in said needle hole; and connecting said means to cam control means driven by the upper shaft; The movement from the non-operating position to the operating position is performed in the necessary order, that is, the open needle hole, the disc, the hook type member, the thread tension holder, the thread take-up, and the swinging hook, and in synchronization with the operating cycle. A sewing machine for implementing the wavy sewing method.