JPH0724278U - Sewing machine needle hole device - Google Patents

Abstract

(57) [Summary] [Purpose] The thread loop formed by the sewing needle of the sewing machine is set at a position where the sword tip of the rotary hook captures it and forms a proper stitch. [Structure] The rotary hook 3 from the center of the ascending / descending path N1 of the sewing needle N
On the inner surface of the needle through hole B of the rotary hook 3 on the opposite side of the needle point 5 of the rotary hook 3 with the needle through hole B including an eccentric needle hole on the side of the sword tip 5 and the hoisting path N1 of the sewing needle N in between. A needle hole device A of the sewing machine is provided by providing an abutting portion C that comes into contact with the sewing thread 1 held by N, and the abutting portion C and the sewing thread 1 are brought into contact with each other to move the thread loop 1a to the rotary hook 3 Make it large near the sword.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a needle hole device of a sewing machine, which sets a thread loop formed by a needle thread of a sewing machine through which a needle thread penetrates through a cloth at a position where a sword tip of a rotary hook catches it securely.

[0002]

[Prior art]

 FIG. 6 is a view showing a needle hole device A of the sewing machine. The needle hole device A of the sewing machine is such that a needle guide member A1 having a circular needle through hole B and the needle guide member A1 are detachable. The needle plate A2 that supports the needle plate A2 is provided, and is installed between the workpiece W and the rotary hook 3 described later. Further, the needle hole device A of this sewing machine has a needle through hole B corresponding to the thickness of the sewing needle N when the sewing needle N is exchanged according to various sewing objects W. The needle guide member A1 is installed on the needle plate A2 such that the center position of the needle through hole B and the ascending / descending path N1 of the sewing needle N coincide with each other.

Further, N is a sewing needle which is moved up and down by a lifting means (not shown), and this sewing needle N is provided with a needle hole Na in the vicinity of the tip portion thereof, and the sewing thread 1 (upper thread 1 ) Is inserted. 3 is a rotary hook (a vertical full rotary hook, a horizontal full rotary hook, a half rotary hook, etc., and the vertical full rotary rotary hook is shown in the figure), and this rotary hook 3 is a sewing thread (lower thread). 2) is provided with an inner hook 3b for storing a bobbin wound with a sword) and an outer hook 3a having a sword tip 5 and rotated by a rotating means (not shown).

Next, the operation of the needle hole device shown in FIG. 6 will be described with reference to FIGS. 7 and 8. The sewing needle N passes through the workpiece W as shown in FIG. 7, passes through the needle through hole B of the needle hole device A of the sewing machine, and descends below the needle plate A2, and then ascends as shown in FIG. Then, the sewing thread 1 is bent below the sewing target W and the needle plate A2 to form the loops 1a on both sides of the needle hole Na. Then, the rotary hook 3 catches the thread loop 1a formed by the sewing needle N with the sword tip 5 of the outer hook 3a, and the thread loop 1a (upper thread) that has been caught with the sewing thread (lower thread) of the bobbin stored in the inner hook 3b. ) Rotate to intersect and form a seam.

By the way, the rotary hook 3 can be adjusted in position so as to approach and separate from the sewing needle N, and even when the rotary hook 3 is replaced with a sewing needle N having a different thickness depending on the workpiece W. The gap between the sewing needle N and the sword tip 5 can be made constant. Further, the inner hook 3b of the rotary hook 3 is provided with an inner hook presser (not shown) so that the inner hook 3b does not follow the outer hook 3a to rotate. A thread loop receiving member (not shown) located on the opposite side of the rotary hook 3 with the lifting path N1 of the sewing needle N in between is installed. The thread loop receiving member and the thread loop 1a are brought into contact with each other to guide the thread loop 1a toward the sword tip of the rotary hook 3 so that the sword tip 5 can properly capture the thread loop 1a.

[0006]

[Problems to be solved by the device]

 However, the above-mentioned conventional sewing machine has the following problems. That is, when the sewing needle N is exchanged according to various sewing objects W and the positions of the sword tip 5 and the sewing needle N of the rotary hook 3 are adjusted according to the thickness of the sewing needle N, the rotary hook 3 Since the position of the yarn loop receiving member installed at the position also changes, the yarn loop receiving member may not be able to perform a predetermined operation depending on the setting position of the rotary hook 3. That is, when the thin sewing needle N is used, when the rotary hook 3 is brought close to the sewing needle N so as to form an appropriate gap between the sewing needle N and the sword tip 5 of the rotary hook 3, the needle N is put in between. On the contrary, the thread loop receiving member provided on the opposite side of the rotary hook 3 is separated from the sewing needle N.

Then, the thread loop receiving member which is too far from the sewing needle N cannot guide the thread loop 1a formed by the sewing needle N to a position where the rotary hook 3 can be properly captured. In this way, the rotary hook 3 rotates without catching the thread loop 1a, and so-called stitch skipping occurs in which no stitch is formed.

Therefore, as a countermeasure against this, as shown in FIG. 9, a pipe 4 having a bulge 4a on one side is provided on the back surface of the needle hole 2 of the needle plate A2, and the yarn loop 1a is rotated by the bulge 4a. There is one in which the hook 3 is made to project only toward the tip of the sword. Therefore, since the left side walls of the needle hole 2 and the pipe 4 in the figure extend downward in a substantially straight line, for example, when a thick sewing needle is used, the sewing needle N is placed with the elevating path of the sewing needle N in between. The left side wall of the pipe 4 which is in contact with the sewing thread 1 to be held has an appropriate gap formed with the ascending and descending sewing needle N so as not to hinder the ascending and descending of the sewing needle N. As a result, the bending of the sewing thread 1 is pushed out from the needle hole Na to the bulge 4a, and the thread loop 1a is formed so as to project only toward the sword tip of the rotary hook 3.

When a thin sewing needle N is used, the gap between the left side wall of the pipe 4 and the ascending / descending sewing needle N becomes large, so that the bending of the sewing thread 1 is expanded from the needle hole Na to the bulge 4a. The amount of extrusion is insufficient. Further, since the right side wall of the pipe 4 also extends downward in a straight line with the needle hole 2, the size of the thread loop 1a is limited by the straight portion of the pipe 4 regardless of the size of the bulge 4a. And it becomes insufficient. Therefore, there is a possibility that the tip of the rotary hook 3 of the rotary hook 3 rotates without catching the thread loop 1a, and a so-called stitch skip, in which no stitch is formed, is generated.

[0010]

[Means for Solving the Problems]

 The needle hole device of the sewing machine according to the present invention is a circular hole including a needle hole that is eccentric to the sword tip side of the rotary hook from the center of the raising and lowering path of the sewing needle, and the tip of the rotary hook with the raising and lowering path of the sewing needle in between. Is formed with an abutting portion that contacts the sewing thread held by the sewing needle on the inner surface of the circular hole on the opposite side, and the thread loop is formed near the sword tip of the rotary hook by bringing the abutting portion into contact with the sewing thread. Thus, the above-mentioned conventional problems are to be solved.

[0011]

[Action]

 The needle hole device of the sewing machine according to the present invention is provided with a circular hole including an eccentric needle hole on the sword tip side of the rotary hook with respect to the center of the ascending / descending path of the sewing needle, and the sword tip of the rotary hook with the ascending / descending path of the sewing needle in between. The contact part formed on the inner side of the circular hole on the opposite side is folded back to both sides from the needle hole of the sewing needle, and is folded back to the side opposite to the tip of the rotary hook with the sewing thread on one side, that is, the sewing needle in between. Touch the sewing thread.

Then, when the sewing needle is raised, the bending of the sewing thread generated on the side opposite to the tip of the rotary hook between the sewing needles is caused by the contact portion from the needle hole of the sewing needle toward the blade tip of the rotary hook. Push it out to make the thread loop largely project only toward the blade point of the rotary hook. As a result, the sword tip of the rotary hook can reliably catch a large thread loop and can form an appropriate stitch without skipping.

[0013]

【Example】

 An embodiment of the present invention will be described with reference to the drawings. It should be noted that the same or corresponding portions as those of the conventional example will be described by attaching the same reference numerals. 1 and 2 are views showing an embodiment of the present invention. In FIG. 1, A is a needle hole device of a sewing machine, and the needle hole device A of this sewing machine has a needle guide member A1 having a needle through hole B through which a sewing needle N is inserted, and the needle guide member A1 is detachable. It is composed of a supporting needle plate A2 and is installed between the workpiece W and the rotary hook 3.

The needle through hole B of the needle guide member A1 is formed by a circular hole including the needle hole, and the center position B1 of the needle guide member A1 is biased from the ascending / descending path N1 of the sewing needle N toward the sword tip of the rotary hook 3. A contact portion C that contacts the sewing thread 1 held by the sewing needle N is formed on the inner surface of the rotary hook 3 opposite to the tip of the sword with the lifting path N1 in between. Further, the contact portion C forms a slight gap with the ascending / descending sewing needle N so as not to hinder the ascending / descending of the sewing needle N.

Next, the operation of the needle hole device A of this sewing machine will be described with reference to FIG. As shown in FIG. 2A, when the sewing needle N penetrates the workpiece W and passes through the needle through hole B of the needle hole device A of the sewing machine, the center of the sewing needle N is biased toward the rotary hook 3 and the ascent / descent path of the sewing needle N. The abutting portion C formed by the inner surface on the side opposite to the rotary hook 3 with N1 interposed therebetween is one side of the sewing thread 1 that is folded back from the needle hole Na of the sewing needle N to both sides of the sewing needle N, that is, the sewing thread. The sewing thread 1 on the side opposite to the rotary hook 3 (left side in the figure) is contacted via the needle N.

Then, when the sewing needle N rises, the sewing thread 1 tries to bend so as to form loops of the same shape on both sides with the needle hole Na as the center, as shown in FIG. The abutment portion C that contacts one side (left side in the figure) of the sewing thread 1 causes the bending of the sewing thread, which occurs as the sewing needle N rises, from the needle hole Na to the other side (right side in the figure) as shown in FIG. 2 (b). ), The thread loop 1a is formed so as to largely project only in the rotary hook 3 direction. That is, the sewing thread 1 that comes into contact with the contact portion C is sandwiched between the sewing needle N and the contact portion C, and even if the sewing needle N rises, it cannot form a bend (loop). It becomes linear along the sewing needle N, and the bending amount of the sewing thread 1 is fed out from the needle hole Na toward the blade point of the rotary hook 3 as the sewing needle N rises. At this time, in the eccentric needle through hole B (circular groove including the needle hole), since there is a large gap on the right side of the sewing needle N, the thread loop 1a is not restricted by the deflection due to this gap and the rotary hook 3 It is extended toward the sword tip.

The thread loop 1a is formed only on the sword tip side of the rotary hook 3, and this thread loop 1a is approximately twice as large as the thread loop 1a formed on the sword tip side of the conventional rotary hook 3. As a result, the sword tip of the rotary hook 3 can reliably catch the thread loop 1a that is largely projected, and it is possible to form an appropriate stitch without skipping. When the sewing needle N is replaced according to the material to be sewn W, if the needle guide member A1 having the needle through hole B and the contact portion C corresponding to the thickness of the sewing needle N is replaced, Similarly, the thread loop 1a can be guided to a position where the blade tip of the rotary hook 3 can be sufficiently captured.

Meanwhile, FIGS. 3 to 4 are views showing another embodiment of the present invention. As shown in FIGS. 3 and 4, the needle hole device A of this embodiment has a large-diameter circular hole B2 centered on the elevating path N1 of the sewing needle N at the opening on the side of the workpiece, and the large-diameter circular hole. A small diameter circular hole B3 including a needle hole that is biased to the sword tip side of the rotary hook 3 from the center of the vertical movement path N1 of the sewing needle N to the lower side of B2 and the vertical movement path N1 of the sewing needle N On the inner side surface of the small-diameter circular hole B3 on the side opposite to the tip of the sword, there is provided an abutting portion C which comes into contact with the sewing thread held by the sewing needle N. The abutting portion C forms a slight gap with the ascending and descending sewing needle N so as not to prevent the ascending and descending of the sewing needle N.

In the needle hole device A of the sewing machine having the above-mentioned configuration, the contact portion C and the sewing thread 1 are provided in the same manner as the above-described one embodiment of the present invention (see FIGS. 2A and 2B). The thread loop 1a is formed in large contact with the rotary hook 3 toward the tip of the rotary hook 3, and the thread loop 1a is reliably caught by the tip of the rotary hook 3 to enable proper seam formation.

Further, in the needle hole device A of this sewing machine, the vertical path N1 of the sewing needle N and the center position of the opening (large diameter circular hole B2) on the side of the workpiece W are set to coincide with each other. As shown in FIG. 4A, the edge of the needle through hole B (circular groove B2) from the ascending / descending path N1 of the sewing needle N is irrespective of the direction in which the workpiece W is fed in the pattern sewing machine or the like. Since the distances a and b are equal to each other and the frictional resistance between the sewing thread 1 and the edge portion of the needle hole device A of the sewing machine is constant, the thread can be tightened uniformly by the balance of the sewing machine and a proper pattern stitch is formed. It

In the needle hole device A of the sewing machine shown in FIGS. 1 and 3, the contact portion C is formed by forming one or two circular holes. For example, as shown in FIG. The contact portion C may be formed by an inclined portion that is inclined so as to project toward the rotary hook as described above, and as shown in FIG. 7B, the contact portion C may be formed below the needle hole device of the sewing machine in the rotary hook direction. The same effect can be obtained by fixing the protruding member protruding toward the contact portion C to form the contact portion C. Further, the needle guide member A1 described in the above embodiments and other embodiments is attached to the needle plate A2 via a positioning member such as a pin, but of course the needle guide member A1 is integrated with the needle plate A2. It may be configured.

[0022]

[Effect of device]

 As described above, the needle hole device of the sewing machine according to the present invention has a needle through hole through which a sewing needle is inserted and a circular hole including a needle hole which is biased from the center of the ascending / descending path of the sewing needle to the sword tip side of the rotary hook. , A contact portion that contacts the sewing thread held by the sewing needle on the inner surface of the circular hole on the side opposite to the rotary hook with the ascending / descending path of the sewing needle in between, and the contact portion and the sewing thread are brought into contact with each other. By eccentricity of the circular hole including the needle hole from the center of the ascending / descending path of the sewing needle, the thread loop is made larger toward the rotary hook, so that the thread loop can be reliably caught by the blade point of the rotary hook. This allows for proper seams without skipping.

[Brief description of drawings]

FIG. 1 is a sectional view showing an embodiment of a needle hole device of a sewing machine according to the present invention.

2A and 2B are views showing the operation of the needle hole device of the sewing machine shown in FIG. 1, in which FIG. 2A shows a lowering of a sewing needle, and FIG. 2B shows a forming of a thread loop when the sewing needle is raised. It is an explanatory side view shown.

FIG. 3 is an explanatory cross-sectional view showing another embodiment of a needle hole device of a sewing machine having a needle through hole having a circular opening centered on a lifting path of a sewing needle.

4A and 4B show a needle through hole of the needle hole device of the sewing machine shown in FIG. 3, in which FIG. 4A is a plan view and FIG. 4B is an explanatory perspective view.

5A and 5B are views showing another embodiment of the needle hole device of the sewing machine, wherein FIG. 5A is a cross-sectional view showing the needle hole device of the sewing machine in which the abutting portion is formed by a slanting protrusion, and FIG. FIG. 8A is a cross-sectional view showing a needle hole device of a sewing machine formed by fixing a protruding member to an abutting portion.

FIG. 6 is an explanatory side view showing a needle hole device of a conventional sewing machine.

FIG. 7 is an explanatory side view showing the time when the sewing needle is descending in the sewing machine including the needle hole device for the sewing machine shown in FIG.

FIG. 8 is an explanatory side view showing the time when the sewing needle is raised in the sewing machine including the needle hole device for the sewing machine shown in FIG. 6;

FIG. 9 is a side view of another example of a sewing machine including a conventional needle hole device for a sewing machine.

[Explanation of symbols]

 1 Sewing thread 1a Thread loop 3 Rotating hook A Sewing machine needle hole device B Needle through hole C Abutment part N Sewing needle W Sewing object

Claims (1)

[Scope of utility model registration request] 1. A sewing machine which is provided between a workpiece and a rotary hook with a needle through hole for inserting a sewing needle and sets a thread loop formed by the sewing needle at a position where a sword tip of the rotary hook captures the thread loop. A needle hole device of this sewing machine, wherein the needle through hole of the needle hole device of this sewing machine has a circular hole including a needle hole that is eccentric to the sword tip side of the rotary hook from the center of the lifting path of the sewing needle, and the lifting path of the sewing needle By forming an abutting portion in contact with the sewing thread held by the sewing needle on the inner surface of the circular hole on the side opposite to the blade point of the rotary hook, and by bringing the abutting portion and the sewing thread into contact with each other, A needle hole device for a sewing machine, wherein a thread loop is formed near the sword tip of a rotary hook.