JPS6125824B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device for sewing thread onto cloth, and more particularly to a sewing machine for sewing decorative thread while forming a loop on the surface of cloth.

What we have traditionally provided for this type of sewing machine is:
In addition to the presser plate for holding the cloth, a guide member for guiding the decorative loop yarn was provided as a separate piece, and the support structure was such that it could move up and down independently. It has a very complicated structure, including the addition of a special mechanism to achieve interlocking operation between the member and the presser plate. However, such a configuration is not practical and has not yet appeared on the market.

Therefore, an object of the present invention is to provide a device which has a simpler structure than the above-mentioned proposed device and which can easily obtain the timing of the two members in a very favorable state. This allows a predetermined effect to be obtained.

The drawings showing the embodiments of the present application will be described below. 1 to 4 show an example in which normal sewing is performed with the clamping body 30 shown in FIG. 5 removed, and these figures will be described first. Reference numeral 1 indicates a base of the sewing machine, 2 a body provided on the base, and 3 and 3' designate protrusions formed upward and downward at one end of the machine body 2. Reference numeral 4 designates an actuating rod that extends through the protrusions 3 and 3' so that it can move up and down and rotate freely, and 5 is a guide tube for the actuating rod 4 that is provided on the upper protrusion 3. Reference numeral 6 denotes a drive shaft provided inside the body 2, which is connected so as to be rotated by an electric motor or the like (not shown). Reference numeral 7 indicates a drive plate attached to the end of the drive shaft 6, and 8 indicates a crankshaft, which constitute a crank mechanism A. Reference numeral 9 indicates a connecting portion between the crankshaft 8 and the operating rod 4. 10 is a needle bar presser provided with a supporting device on a part of the operating rod 4;
0' indicates a locking portion of the needle bar presser 10, which is formed so as to be lockable to a head 14' of a needle bar 14, which will be described later. Reference numeral 11 denotes a tension spring that is tensioned between the needle bar presser 10 and the connecting portion 9 as necessary, and is always connected to the needle bar presser 1.
It has elasticity to return the 0 to the predetermined position as shown in the figure. Next, reference numeral 12 indicates a holding plate provided on the lower protrusion 3' of the fuselage 2.
It is configured to be able to freely reciprocate with respect to the In this embodiment, the actuating rod 4 is configured to be freely rotatable in the left and right directions. Reference numeral 13 indicates a contact portion of the holding plate 12, which is formed so as to be brought into contact with and interlocked with a stepping motor or the like (not shown). In addition, when a plurality of sewing machines in this embodiment are used in parallel, the contact portions 13 of the respective holding plates 12 are positioned in parallel on a straight line, and these machines are operated by a single drive source. The switching operation may be performed by a switching operation shaft (not shown) or the like that is interlocked with the switching operation shaft. 14,14,
Reference numeral 14 indicates a plurality of (three needle bars are shown in the figure) penetrating the holding plate 12 so as to be able to move up and down, and these needle bars move up and down parallel to the aforementioned operating rod 4. It is designed to be easy to use. 14',1
4' and 14' indicate the heads of the needle bars, respectively.
15a, 15a. 15a is a first spring fitted to each of the above needle bars, and 15a is a first spring fitted to each of the above needle bars,
8a, and urges the presser plate 18 to always return to a fixed raised position. 1
5b, 15b. 15b is a second spring fitted to each needle bar, and is interposed between the connecting portion 18a of the presser plate 18 and the head 14' of the needle bar 14, and is used to keep the needle bar at a constant raised position. It is energized so that it returns to . The relationship between the springs 15a and 15b is as follows. That is, as shown in FIGS. 1 and 2, both are stretched to the maximum at all times. However, the needle bar presser 10'
When it falls as shown in Figures 3 and 4,
The spring 15a located below the connecting portion 18a of the presser plate 18 is compressed to a large degree as shown in the figure, whereas the spring 15b located above the connecting portion 18a is compressed to a small degree as shown in the figure.
This means that the spring force of the lower spring 15a of the connecting part 18a is weak, and the spring force of the upper spring 15b of the connecting part 18a is weak.
This means that the spring force is stronger than that. Therefore, when the needle bar presser foot 10' is raised from the state shown in FIGS. 3 and 4, the second spring 15b, which has a strong spring force and is located above the connecting portion 18a, expands first, and then the connecting portion 18a expands. The first spring 1 with weak spring force is located on the lower side of
5a continues to elongate, finally reaching the state shown in FIGS. 1 and 2. Both springs 1 above
The relationship between 5a and 15b is as described above. Reference numeral 16 indicates a normal needle fixed to the lower end of each needle bar 14, and reference numeral 17 indicates a needle stop portion for detachably fixing the needle 16 to the needle bar. In addition, 18b is a cloth presser part in a presser plate, 19 is a thread guide, and 20 is a hook installed inside the base 1.

Next, a normal sewing operation sequence using the sewing machine having the above configuration will be explained. First, by starting a motor (not shown), the drive shaft 6 and the drive board 7 provided integrally therewith are rotated. This rotation of the drive plate 7 causes the actuation rod 4 to reciprocate in the vertical direction via the crankshaft 8. As the actuating rod 4 moves downward, the locking portion 10' of the needle bar presser 10 locks the multiple needle bars 1.
As shown in FIGS. 3 and 4, one of the needles 4, together with its presser plate, is pushed downward against the springs 15a and 15b of the needle bar. With this, the presser plate 18
The cloth presser portion 18b is used to press the cloth (not shown) on the substrate 1.
While pressing down, the needle 16 at the lower end of the needle bar penetrates the fabric,
The thread at the tip of the needle is scooped up by a hook 20 in the base 1 and used for sewing as is commonly known. Next, as the above-mentioned operating rod 4 rises, the needle bar presser foot 10 also rises, and the needle bar spring 15a,
Due to the elasticity of 15b, it returns to the upper position together with the presser plate 18. This completes one stroke of the sewing operation of the needle bar 14.

Next, if you want to continue sewing with a different thread by lowering the other needle bar 14, operate a driving device such as a stepping motor (not shown) while the needle bar presser foot 10 is in the raised position. The abutting portion 13 of the retaining plate 12 is repositioned, thereby rotating the retaining plate 12, and changing the position of the needle bar 14.
The head 14' of the needle bar presser 10 is attached to the locking part 1
Move it to the position below 0'. If the needle bar presser foot 10 is lowered in this state, sewing similar to that described above can be performed using the newly replaced needle bar 14. Similarly, the needle bars can be sequentially switched according to a predetermined program. Therefore, if each of these needle bars is equipped with threads of different types and colors, decorative stitches using threads of different types and colors can be sequentially sewn. In addition, the rotation angle of the holding plate 12 when switching from one needle bar to the next needle bar is compared with the above case by 1/2.
If the rotation angle is set to Skipping stitches of commonly known sewing machine stitches can also be easily performed.

Next, the clamping body 30 shown in FIG. 5 will be explained. This clamping body 30 is used in the state shown in FIGS. 6 to 10. In FIG. 5, the clamping body 30 is formed of one material by press molding, and in this, 3
Reference numeral 1 denotes a guide member, which is a portion that runs along the main body portion 21 of the presser plate 18, as shown in FIG. 3
2 is a connector fixed to the upper part of the guide member 31;
As shown in FIG. 6, this is a portion that is placed vertically movably within a guide portion 22 formed in the main body portion 21 of the presser plate 18. 32a is a large diameter portion for preventing slippage. 33 and 34 are connecting members, and the guide member 3
1 and is formed integrally. 35 is the connecting member 3
3 through which the needle bar 14 can be inserted and removed freely. 36 indicates a spring receiving portion around this through hole. Reference numeral 37 denotes a clamping member connected to the lower end of the connecting member 34, and as shown in FIG. 6, the clamping member 37 is adapted to be overlapped with the lower side of the presser portion 18b in a manner that allows the clamping member to move away from or near the bottom of the presser portion 18b. Reference numeral 38 indicates a needle hole bored in the clamping member 37. 39 is a spring interposed between the spring receiving portion 36 and the spring receiving portion 23 of the holding plate 18, and a compression spring is used.

Next, 51 is a rotation regulating body fixed (for example, welded) to the needle bar 14, and a thin rod-shaped connecting piece 52 is provided at the lower part. Reference numeral 53 denotes a regulating hole formed in the connecting portion 18a of the presser plate 18, into which the connecting piece 52 is inserted so as to be freely removable. Reference numeral 54 denotes an engagement piece, which is made of one piece with the regulating body 51. Reference numeral 55 denotes a lifting body attached to the needle bar presser 10, and is provided at a position where it can face the engagement piece 54.

Next, the operation of loop stitching using the clamping body 30 will be described with reference to FIGS. 6 to 10. In these figures, 41
numeral 42 indicates a cloth to be sewn, numeral 42 indicates a loop thread, and numeral 43 indicates a sewing thread. First, when the needle bar presser 10 is slightly lowered from the state shown in FIG. 6, the first spring 15a, which has a weaker biasing force than the second spring 15b, is compressed and the needle bar 14 is lowered, as shown in FIG. As a result, the spring 39 with the weakest urging force is expanded. The cloth presser portion 18b overlaps the clamping member 37, and the loop thread 42 passed through the needle hole 38 is sandwiched between the cloth presser portion 18b and the clamping member 37. Next, when the needle bar presser 10 is further lowered, the first spring 15a is further compressed, and the needle bar 14 is further lowered. In this case, since the cloth presser portion 18b overlaps with the clamping member 37, they descend together with the loop yarn 42 clamped therebetween. (The biasing force of the spring 39 only needs to be weak enough to clamp the loop yarn 42 between the presser foot 18b and the clamping member 37 and lower it from the state shown in FIG. 7 to FIG. 8.) Then, the clamping member 37 comes into contact with the cloth 41, and the cloth presser part 18
b holds the cloth 41 through its clamping member 37.
Thereafter, when the needle bar presser 10 further descends, the second spring 15b contracts and the needle bar 14 descends further, causing the needle 16
pierces the cloth 41 through the needle hole of the cloth presser foot 18b and the needle passage hole 38 of the clamping member 37, as shown in FIG. 8, and the needle bar 14 reaches the bottom dead center. In this case, the needle 16 pierces the loop thread 42 inserted into the needle hole 38 and passes through the cloth 41 as shown in FIG.
8, the loop thread 42 existing between the cloth 41 and the clamping member 37 in the state shown in FIG. 7 becomes a loop 44 as shown in FIG. After that, in the process of raising the needle bar presser 10, the second spring 15b, which has the strongest biasing force, first expands, the needle bar 14 rises, and the needle 16 comes out of the cloth 41. In this case, even if the needle 16 is strongly bitten by the cloth 41, the lifting body 55 of the needle bar presser foot 10 engages with the engagement piece 54 and forcibly pulls up the needle bar 14.
The withdrawal of the needle 16 from the needle 16 is done quickly.
At this time, since the connecting piece 52 moves up inside the regulating hole 53, the rotation regulating body 51 does not rotate about the axis of the needle bar 14, and therefore the pulling body 55 and the engaging piece 54 The engagement is reliably achieved. Then needle 16
When the needle is pulled out of the cloth 41 and the needle stopper 17 comes into contact with the lower surface of the spring receiver 23 on the presser plate 18,
The needle bar 14 and the presser plate 18 are raised together by the biasing force of the first spring 15a. In this case, the clamping body 30, which is urged upward by the spring 39, also rises together. Eventually, the peripheral edge of the through hole 35 in the connecting member 33 of the clamping member 30 comes into contact with the regulating member 45 (for example, the needle bar support attached to the holding plate 12), resulting in a state as shown in FIG. 9. In this case, since the loop thread 42 is sewn onto the cloth 41 to form the loop 44 as described above, the clamping member 3
The loop thread 42, which is held between the thread 7 and the presser foot 18b, is let out downward when it passes between them in the above-mentioned upward movement process. Next, when the needle bar presser 10 further rises, the presser plate 18 and the needle bar 14 further rise due to the biasing force of the first spring 15a, causing the needle bar 1
4 reaches top dead center. In the process, spring 39
is compressed as shown in FIG. As a result, the presser foot 18b and the clamping member 37 are separated from each other as shown in FIG. 10, resulting in a state similar to that shown in FIG. 6. If the loop yarn 42 is a stretchable yarn, the loop yarn 42 is attached to the clamping member 3 in the process of moving from FIG. 8 to FIG.
Since there is no need for the spring 39 to slip between the presser foot 7 and the presser foot 18b (it is only necessary to extend it), the spring force of the spring 39 may be strong enough to prevent the spring 39 from slipping through.

As described above, in this invention, the holding plate 12
It consists of a needle bar 14 mounted so as to be movable up and down with respect to the holding plate 12, and a presser plate 18 mounted so as to be movable vertically with respect to the needle bar 14. In this sewing machine, the cloth 41 is held down by the cloth presser foot 18b, and the cloth 41 is sewn through a needle 19 provided at the tip of the needle bar. A separately formed clamping member 37 is provided opposite to the clamping member 37 so as to be able to move away from and close to the clamping member 3.
7 is a spring 39 that holds the material presser portion 18b and the clamping portion 3.
7 are biased in the direction of approaching each other,
Even if the needle bar 14 is simply moved up and down to perform a sewing operation similar to normal sewing, the clamping member 37 can hold the loop thread 42 between it and the presser foot 18b when it is lowered.
The loop 44 is sewn onto the cloth 41 by passing the needle 19 provided at the tip of the needle bar through the cloth 41, and sewing is completed. After that, move the needle bar 14
Even in the ascending process, the loop thread 42 passes through the gap corresponding to the dimension required to form the next loop between the clamping member 37 and the presser part 18b, which remain overlapped with each other due to the biasing force of the spring. Let me,
It has a feature that allows beautiful sewing of the loop thread 42.

Moreover, even if such an effect is produced, the above-mentioned effect can be obtained even with a simple structure in which the upper part of the clamping body 30 is simply attached to the presser plate 18.

Furthermore, since the clamping body 30 is structured to be attached to the holding plate 18, an extra structural member for supporting the clamping body 30 is not required, and there is an effect that it can be mounted even in a pinched place. This means that a plurality of needle bars 14, 14,
... 14 are arranged in parallel, and each needle bar 14, 14, 14
. . . Even in the case where a structure in which the presser plates 18 are attached to each of the presser plates 14 is required, the structure of the present invention has the feature that it can be attached, and is excellent in expanding the application of the multi-axis sewing machine. effective.

[Brief explanation of the drawing]

The drawings show an embodiment of the present application, in which Fig. 1 is a front view with the clamping member removed, Fig. 2 is a sectional view of the same side, and Fig. 3 is a front view showing the operating state of the state shown in Fig. 1. 4 is a side sectional view thereof, FIG. 5 is a perspective view of the clamping member, and FIGS. 6 to 10 are side sectional views showing the operating state when sewing is performed with the clamping member attached. 4... Operating rod, 10... Needle bar presser, 12... Holding plate, 14... Needle bar, 15a... First spring, 15
b...Second spring.

Claims (1)

[Claims] 1 Consists of a holding plate, a needle bar attached to the holding plate so as to be movable up and down, and a presser plate attached to the needle bar so as to be movable up and down, and provided at the lower end of the presser plate. In a sewing machine that presses the cloth with a presser foot and sews the cloth through a needle provided at the tip of the needle bar, there is a clamp formed separately below the presser foot on the presser plate. The members are disposed opposite each other so as to be able to move away from each other, and the clamping member is biased by a spring in a direction in which the clamping member and the clamping member approach each other in order to clamp the loop yarn between the clamping member and the clamping member. A sewing machine characterized by: