JPH08299645A - Sewing machine hook device - Google Patents

Abstract

(57) [Abstract] [Purpose] By forming an inclined surface or an arc surface on at least one of the contact portions between the hook stopper and the stopper, the upper thread of the needle thread between the hook stopper and the stopper is formed. It is an object of the present invention to provide a hook device for a sewing machine that can reduce noise significantly by facilitating passage and eliminating the need for an opener mechanism. [Constitution] A rotating outer hook 2 supports an inner hook 1 so as to be rotatable relative to the inner hook 1, and an outer hook of the inner hook 1 is loosely fitted between a pair of stoppers 9a, 9b provided on a needle plate 8. The stopper 3 is provided, and the rotation of the inner hook 1 is restricted within a certain range by the hook stopper 3 and the pair of stoppers 9a and 9b. Sloped surfaces 3A are formed on both side surfaces of the hook stopper 3, respectively.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hook device for a sewing machine, and more particularly to a hook device for controlling the rotation of an inner hook within a certain range.

[0002]

2. Description of the Related Art Conventionally, as a hook device for this type of sewing machine,
The one shown in FIGS. 9 to 12 can be seen. 9 is a perspective view of the outer hook with the inner hook attached, FIG. 10 is an exploded perspective view of the hook device, FIG. 11 is a perspective view of the needle plate, and FIG. 12 is a structure of the hook device of the two-needle sewing machine. It is a top view.

As shown in FIGS. 9 and 10, the hook device is
An inner pot 1 and an outer pot 2 are provided. The inner hook 1 is provided with a hook stopper 3, an opener stopper 4, a bobbin thread feeding port 5, a bobbin support 6 and a race 7. The hook stopper portion 3 is a protrusion provided in the outer horizontal direction from the upper edge of the inner hook to prevent the inner hook 1 from rotating, and this is loosely fitted in the groove 9 of the needle plate 8 shown in FIG. It The groove 9 is formed as a space between two stoppers 9a and 9b provided on the back surface of the needle plate 8, and the width of the groove 9 is set to be larger than the width of the hook stopper 3. The opener contact 4 is a cam to which an opener described later faces. The bobbin thread feeding port 5 is a bobbin 10 mounted in the inner hook 1 (see FIG. 12).
It is a slit that is used when the lower thread is taken out. The bobbin support 6 is a spindle for mounting the bobbin in the inner hook 1. A bobbin retainer 14 is provided on the upper end of the bobbin support 6. The race 7 is a protrusion having a notched portion provided on the outer circumference of the inner hook 1.

The outer hook 2 has a sword tip 20 and a race groove 21.
A shuttle shaft 22 is provided. The sword tip 20 is a claw for catching a loop formed in the upper thread and forming a stitch with the lower thread by rotating around the outer circumference of the inner hook 1.
The race groove 21 is formed by the race 7 provided in the inner hook 1.
Is a groove into which is fitted. The shuttle shaft 22 has a function of transmitting a rotation from a lower shaft of a sewing machine (not shown) to the outer shuttle 2 and, at the same time, driving an opener which will be described later. For this reason, an eccentric shaft 25 is integrally formed on the upper part of the shuttle shaft 22. Is formed in.

On the other hand, in the hook device, an opener mechanism is added to the outside of the inner hook 1 and the outer hook 2. As shown in FIG. 10, the opener mechanism includes an opener 30, an opener support 31, and an opener link 32. The opener link 32 is a link that connects the eccentric shaft 25 of the shuttle shaft 22 and the opener support 31 in an interlockable manner.

The shuttle device configured as described above is shown in FIG.
As shown in, the sewing machine is mounted on the bed. The openers 30 are arranged in a positional relationship as shown in FIG.

Next, the operation of the shuttle device configured as described above will be described.

In FIG. 12, when the sewing machine is driven,
The outer hook 2 fully rotates clockwise (direction of arrow A), and the opener 30 swings in the direction of arrow BC with the opener support shaft 36 as a fulcrum. Due to this swinging motion of the opener 30, the needle thread inserted into the needle can easily pass through the hook stopper portion 3 and go around the outer circumference of the inner hook 1.

The situation in which the upper thread goes around the outer circumference of the inner hook will be described in detail with reference to FIGS. 14 to 16. FIG. 14 is a plan view for explaining a situation in which the upper thread is delivered by the shuttle device, and FIG. 15 is a plan view for explaining a situation in which the lower thread is similarly delivered,
FIG. 16 is a sectional view taken along the line EE of FIG.

In FIG. 14, as the sword tip 20 of the outer hook 2 which has caught the loop of the upper thread 50 rotates in the direction of arrow A, the loop of the upper thread 50 which advances around the outer circumference of the inner hook 1 is at the position 50 in the drawing.
It sequentially moves from a to the position 50b shown in the figure. The position 50a shown in the figure shows the moment when the needle thread 50 from the needle hole 52 leaves the stopper 9a of the needle plate 8 and is about to enter the groove 9. The opener 30 is fully displaced at this point in the direction of arrow C. Therefore, the hook stopper 3 of the inner hook 1 and the stopper 9a
A gap is created between the needle thread 50 and the needle thread 50, and as a result, the needle side needle thread 50 passes through the gap between the hook stopper 3 and the stopper 9a, and moves from the solid line position 50c to the broken line position 50d.

Next, the operation of the opener will be described. FIG.
The path of the lower thread 51 fed from the bobbin 10 is shown in FIG. The position of the bobbin thread feeding port 5 is within a range of 180 ° in the direction opposite to the rotation direction of the outer hook 2 with reference to the line segment connecting the center of the bobbin support 6 and the hook stopper 3. For this reason, the feeding tension of the lower thread 51 acts in the direction of rotating the inner hook 1 in the direction of arrow A.

On the other hand, the inner hook 1 receives a rotational force in the direction of arrow A due to the friction torque with the outer hook 2. Therefore, the hook stopper portion 3 at the time of sewing is pressed by the stopper 9a by the sum of these pressing forces. The opener 30 rotates the inner hook 1 in the direction opposite to the arrow A against the pressing force to form a gap between the hook stopper 3 and the stopper 9a, so that the needle thread 50 can easily pass therethrough. It is a thing.

After that, the rotation further proceeds and the upper thread 50 is moved to the position shown in FIG.
4, the opener 30 is maximally displaced in the arrow B direction. Along with this, the hook stopper 3 and the needle plate 8
A gap is formed between the upper thread 50 and the stopper 9b, and the loop of the upper thread 50 easily passes through. Then, when the upper thread 50 finishes rotating around the inner hook 1, the lower thread 51 and the lower thread 51 are intertwined with each other to form a seam.

[0014]

As described above, in the hook device of the conventional sewing machine, the opener mechanism is indispensable. As a result, the opener and the inner hook are contacted with each other, and
The hook stopper and the needle plate stopper collided when the sewing machine was driven, and a large amount of noise was generated. This noise was a very offensive noise caused by the collision and made the sewing manufacturer uncomfortable. Further, there is a problem that the inner hook detent portion is broken due to metal fatigue due to collision with the opener.

The present invention has been made in order to solve the above-mentioned problems, and by forming an inclined surface or an arc surface on at least one of the contact portions of the hook stopper portion and the stopper, An object of the present invention is to provide a hook device for a sewing machine, which facilitates passage of the upper thread between the hook stopper and the stopper and which does not require an opener mechanism, thereby significantly reducing noise.

[0016]

To achieve this object, a hook device of a sewing machine according to the present invention comprises an outer hook rotatably supported around an axis and an outer hook inside the outer hook. An inner hook which is rotatably supported with respect to the inner hook, and has an outer hook provided with a hook stopper, and an inner hook which is provided on the sewing machine main body side and is engaged with the hook stopper of the inner hook. In particular, an inclined surface or a circular arc surface is formed on at least one of the contact portions of the hook stopper and the stopper, which is provided with a stopper that prevents rotation of the hook with the outer hook within a certain range. It was done.

Further, the hook stopper portion may be constituted by a spherical body which is rotatably supported around an axis on the outer peripheral portion of the inner hook.

Further, the hook stopper portion may be constituted by a cylindrical body rotatably supported around an axis on the outer peripheral portion of the inner hook.

[0019]

According to the hook device of the sewing machine of the present invention having the above-mentioned structure, when the outer hook rotates when forming the stitches, the inner hook supported by the outer hook also tries to rotate together. The rotation of the inner hook is restricted within a certain range by the contact between the hook stopper and the stopper. Then, at this time, the upper thread is caught by the sword tip of the outer hook and circulates around the hook to form an upper thread loop formed by the upper thread. Pass through between the stopper and the stopper. In this case, since the inclined surface or the arcuate surface is formed on at least one of the contact portions of the hook stopper portion and the stopper, the upper thread can easily slip through and the opener mechanism is not required. Therefore, the collision noise between the inner hook detent portion and the opener, which has been conventionally generated, is hardly generated.

Further, if the hook stopper portion is constituted by a sphere that is rotatably supported around an axis on the outer peripheral portion of the inner hook, when the upper thread slips between the sphere and the stopper. In addition, the sphere rotates to reduce the resistance of the upper thread at the time of slipping through, and the slipping-out action is more easily and smoothly performed.

Further, if the hook stopper portion is constituted by a cylindrical body which is rotatably supported around an axis on the outer peripheral portion of the inner hook, the upper thread is provided between the cylindrical body and the stopper. When slipping through, the cylindrical body rotates to reduce the resistance of the needle thread at the time of slipping through, so that the slipping-out action is more easily and smoothly performed.

[0022]

Embodiments of the present invention will be described below with reference to the drawings.

1 and 2 show a first embodiment embodying the present invention. FIG. 1 is a plan view of a horizontal full rotation type hook device, and FIG. 2 is a hook stopper and stopper of an inner hook. It is an action explanatory view showing the contact state of the contact part with.

In FIG. 1, the outer hook 2 which is rotatably supported around the vertical axis below the needle plate 8 having the needle hole 52 is adapted to rotate in the direction of arrow A when forming a stitch. A sword tip 20 for catching the upper thread 50 is provided on the outer peripheral portion thereof. The outer pot 2 accommodates and supports the inner pot 1 so as to be relatively rotatable. A bobbin 10 wound with a bobbin thread is housed and held in the inner hook 1 by a bobbin presser 14, and a pair of stoppers 9a, which are arranged at a constant interval on the needle plate 8, are provided on the outer peripheral portion. A hook stopper 3 that is loosely fitted is provided between 9b. In the hook stopper 3,
As shown, inclined surfaces 3A are formed on both sides thereof. Therefore, the rotation of the inner hook 1 is regulated within a slight fixed range by contacting the pair of stoppers 9a or 9b with which the two inclined surfaces 3A of the hook stopper 3 contact each other. There is.

The operation of the shuttle device configured as described above will be described below.

That is, when the outer hook 2 is rotated in the direction of arrow A, the needle thread (not shown) goes through the cloth and needle hole 52 together with the needle, and the upper thread protrudes below the needle plate 8. After 50 is captured by the sword tip 20 of the outer hook 2, the loop of the upper thread advances to the contact portion between the hook stopper 3 and the stopper 9a. Here, the relationship between the contact portion and the upper thread 50 is shown in FIG.
And FIG. 13 showing the same relationship by the conventional one,
Description will be made by comparing the conventional example with the present example.

In this embodiment, as shown in FIG. 2, as the outer hook 2 rotates, the upper thread 50 caught by the blade tip 20 of the outer hook 2 is tensioned in the direction D of FIG. In the state of being pulled at T1, the force acting on the inclined surface 3A of the hook stopper 3 is, as shown in FIG.
A component in a direction perpendicular to A and a component in a direction parallel to the inclined surface 3A.

Similarly, considering the conventional one in FIG. 13, the force relationship acting on the hook stopper portion 3 is as shown in FIG. Therefore, in the conventional case, the force of the component acting to press the hook stopper portion 3 against the stopper 9a is large, so that the thread slip-out resistance is increased and the thread is not smoothly removed. In the case of the invention, the force acts rather to separate the hook stopper 3 from the stopper 9a, so that the upper thread 50 moves between the inclined surface 3A of the hook stopper 3 and the stopper 9a. It is possible to pass lightly and smoothly.

As described above, as a result of the good thread pulling action of the upper thread 50, the opener mechanism which has been conventionally required is not necessary, and the collision between the hook stopper portion 3 and the stopper 9a which is generated by the pulling back of the opener. There is no sound, and quiet sewing is possible. Further, since the opener mechanism is unnecessary, the structure of the shuttle device is simplified.

The present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the invention. Below, some modified examples are shown. The same names and reference numerals are used for the same parts as those in the first embodiment, and the description thereof will be omitted.

That is, first, in FIG. 3 showing the second embodiment of the present invention, the hook stopper portion 3 of the inner hook 1 is formed such that the tip end portion thereof has an arc shape in a plan view. According to this embodiment, when the inner hook 1 is rotated, the arcuate surface of the hook stopper 3 comes into contact with the vertical surface of the stopper 9a or 9b, and the same operation as the first embodiment, The effect can be obtained.

Next, referring to FIGS. 4 and 5 showing the third embodiment of the present invention, the hook stopper is composed of a pair of upper and lower projections 60 provided on the outer peripheral portion of the inner hook 1, and the respective projections 60. And a sphere 61 rotatably supported in between. As shown in FIG. 5, the sphere 61 has the pair of protrusions 6
It is fitted to the non-threaded portion of the screw shaft 62 that is screwed vertically to 0, and is rotatably supported around the non-threaded portion. In the case of this embodiment, when the inner pot 1 rotates, the arcuate surface of the spherical body 61 comes into contact with the vertical surface of the stopper 9a or 9b, and the spherical body 61 and the stopper 9
When the upper thread slips through between a and 9b, the spherical body 61 rotates and the resistance of the upper thread at the time of slipping is reduced, so that the slipping action is more easily and smoothly performed.

Next, referring to FIG. 6 showing a fourth embodiment of the present invention, the hook stopper portion is provided with a pair of upper and lower projections 70 provided on the outer peripheral portion of the inner hook 1, and is rotatable with respect to each of the projections 70. And a supported cylindrical body 71. The cylinder 71
Is fitted into a non-threaded portion of a screw shaft 72 that is vertically screwed to the pair of protrusions 70, and is rotatably supported around the non-threaded portion. In the case of this embodiment, when the inner pot 1 rotates, the circular arc surface of the cylindrical body 71 comes into contact with the vertical surface of the stopper 9a or 9b, and the same operation as the third embodiment, The effect can be obtained.

Next, referring to FIG. 7 showing the fifth embodiment of the present invention, the hook stopper portion 80 is formed in an arc shape in plan view, while the stoppers 9a and 9b of the needle plate 8 have circular tips. It is formed in an arc shape. Also in this embodiment, when the inner hook 1 rotates, the arcuate surface of the hook stopper 8080 causes the stopper 9 to move.
Since it comes into contact with the circular arc surface of a or 9b, the same action and effect as those of the first embodiment can be obtained.

Next, referring to FIG. 8 showing the sixth embodiment of the present invention, the shape of the hook stopper 3 of the inner hook 1 is the same as that of the conventional one, but a pair of stoppers 9a of the needle plate 8 are provided. , 9b are formed with inclined surfaces 90, respectively. When the inner hook 1 rotates, the hook stopper 3 comes into contact with the inclined surface 90 of the stopper 9a or 9b, and the same operation and effect as those of the first embodiment can be obtained.

[0036]

As is apparent from the above description, according to the hook device of the sewing machine of the present invention, at least one of the contact parts of the hook stopper and the stopper of the inner hook has an inclined surface or an arc surface. Since the upper thread is formed, the upper thread always slips easily and lightly between the hook stopper and the stopper. In addition, the conventional opener mechanism is not required, and therefore, there is an effect that the hitting noise between the inner hook preventing portion and the opener which is conventionally generated is not generated.

[Brief description of drawings]

FIG. 1 is a plan view showing a hook device of a sewing machine according to a first embodiment of the present invention.

FIG. 2 is an explanatory view showing a contact portion between a hook stopper portion and a stopper according to the first embodiment.

FIG. 3 is a plan view showing a hook device of a sewing machine according to a second embodiment of the present invention.

FIG. 4 is a plan view showing a shuttle device for a sewing machine according to a third embodiment of the present invention.

5 is an enlarged cross-sectional view taken along the line FF of FIG.

FIG. 6 shows a fourth embodiment of the present invention and is a side view of a hook stopper.

FIG. 7 shows a fifth embodiment of the present invention and is a plan view of a hook stopper.

FIG. 8 shows a sixth embodiment of the present invention and is a plan view of a hook stopper.

FIG. 9 is a perspective view of a shuttle device of a conventional sewing machine.

FIG. 10 is an exploded perspective view showing a shuttle device of a conventional sewing machine.

FIG. 11 is a perspective view showing a needle plate of a conventional sewing machine.

FIG. 12 is a plan view showing the configuration of a shuttle device for a conventional two-needle sewing machine.

FIG. 13 is an explanatory diagram showing a contact portion between a hook stopper and a stopper of a conventional two-needle sewing machine.

FIG. 14 is a plan view for explaining a situation in which a needle thread is fed by a conventional shuttle device.

FIG. 15 is a plan view for explaining a situation in which a bobbin thread is fed by a conventional shuttle device.

16 is a cross-sectional view taken along the line EE in FIG.

[Explanation of symbols]

 1 Inner hook 2 Outer hook 3 Hook stopper 3A Inclined surface 9a Stopper 9b Stopper 60 Protrusion 61 Sphere 70 Protrusion 71 Cylindrical body 80 Kettle stopper 90 Slope

Claims (3)

[Claims] 1. An outer hook rotatably supported around an axis, a rotatably supported inside the outer hook rotatably with respect to the outer hook, and an outer hook having a hook stopper. A sewing machine provided with an inner hook provided with the sewing machine, and a stopper provided on the sewing machine main body side and engaging with the hook stopper portion of the inner hook to prevent the inner hook from rotating together with the outer hook within a certain range. A shuttle device for a sewing machine, wherein an inclined surface or an arc surface is formed on at least one of the contact portions of the shuttle stopper and the stopper. 2. The hook device for a sewing machine according to claim 1, wherein the hook stopper portion is constituted by a sphere that is rotatably supported around an axis on an outer peripheral portion of the inner hook. 3. The hook device for a sewing machine according to claim 1, wherein the hook stopper portion is constituted by a cylindrical body rotatably supported around an axis on an outer peripheral portion of the inner hook.