JP2001276463A - Sewing machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To facilitate setting of a bobbin thread and allow visual checking at low cost. SOLUTION: This sewing machine is provided with a bobbin compartment 7b provided within a bed part 1a to detachably house a bobbin 14; a bobbin storage hole 4a opened thereabove; a slide plate 5 arranged over the bobbin storage hole 4a and being able to open and close by sliding; a tension generating part 11 comprising a thread tension bracket 8 and a thread tension spring 9 mounted in overlapping relation in the bobbin compartment 7b for imparting resistance to a bobbin thread brought out of the bobbin 14; an opening 5b located in front of a cut groove 8a provided in the thread tension bracket 8; and a slit 5a formed the slide plate 5 in a diagonal direction opposite to a needle hole 4b, in a position behind the cut groove 8a from the opening 5b.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a sewing machine.

[0002]

2. Description of the Related Art A horizontal shuttle mechanism that does not require a bobbin case in a home sewing machine has become mainstream in recent years. A lower thread supply mechanism of a sewing machine having a horizontal hook of this type is arranged so that a lower thread bobbin receiving section of a cylindrical container of an inner shuttle is located below a lower thread bobbin receiving port provided on a needle plate of a bed portion. It is configured.

[0003] The lower thread bobbin accommodating section is provided with a tension generating section for giving resistance to pulling out the lower thread drawn out from the lower thread bobbin. The tension generating portion is configured by mounting a thread tension plate and a thread tension spring in a recess formed along the inner peripheral surface of the inner hook in a superposed state.

[0004] A cut groove is formed in the thread tension plate, and the lower thread is passed between the thread tension plate and the thread tension spring from the cut groove, so that resistance is given by the scissoring force of these two. It is configured to be in a state suitable for sewing.

[0005] In setting a new bobbin thread, the user has to place the bobbin bobbin in the bobbin accommodating section and then pass the leading end portion of the bobbin thread pulled out from the bobbin bobbin through the tension generating section. No. However, at this time, while watching the user from above, the user has to perform a fine work of passing the cut end of the lower thread by hooking the leading end of the lower thread to the open part of the fine cut groove, which is troublesome. There was a disadvantage that it took time.

If the lower thread passes without passing through the tension generating portion correctly, the lower thread tension is weakened, the supply amount of the lower thread is increased, and the balance with the upper thread is lost. . There has been a demand for solving these problems and making it easier to set a new lower thread.

As a prior art, Japanese Patent Application Laid-Open No. 10-14648
No. 9 discloses a lower thread supply mechanism of a sewing machine provided with a guide member located above a tension generator of an inner hook and guiding a lower thread to the tension generator. By making the outer edge of the guide member extend in an arc shape, the user can set the lower thread by simple work such as guiding the lower thread drawn from the lower thread bobbin along the outer edge of the guide member. became.

[0008]

However, in the prior art 1, since the guide member must be provided directly above the tension generating portion arranged in the inner hook, the upper thread is connected to the tension generating portion and the guide member at the time of sewing. If the clearance between the tension generating section and the guide member is too small, the upper thread will have resistance, and will not pass around the bobbin case, and the tension balance between the upper thread and the lower thread will be lost. There arises a problem that a beautiful seam cannot be formed and cannot be formed. There is a problem that dimensional accuracy is required to secure this clearance, which leads to an increase in cost. In addition, since a new guide member must be added, there is a problem that the cost is increased.

In the prior art 1, while the bobbin thread is guided unconsciously, since the guide member is provided immediately above the tension generating section arranged in the inner hook, it is visually observed that the bobbin thread is guided to the tension generating section. There was a problem that the confirmation could not be performed, and even if the guidance of the lower thread to the tension generating section failed, it could not be understood.

Further, in prior art 1, when placing the bobbin thread bobbin in the inner hook receiving section, the cover of the accommodating section must be removed, and after setting the bobbin thread, the lid must be placed somewhere on the bobbin. Could be lost.

The present invention has solved the above-mentioned problems, and provides a low-cost sewing machine in which the setting of the lower thread in the tension generating section is easy and the state in which the lower thread is guided to the tension generating section can be visually confirmed. I do.

[0012]

Means for Solving the Problems In order to solve the above technical problems, the technical means (hereinafter referred to as first technical means) taken in claim 1 of the present invention is provided in a bed portion. A lower thread bobbin accommodating section for detachably accommodating the lower thread bobbin; a lower thread bobbin accommodating port opened in the bed section for detaching the lower thread bobbin; and a lower thread bobbin accommodating port. A sliding plate that is substantially flush with the bed portion when closed, and is slidable in a direction opposite to a needle hole provided in the bed portion, and a thread tension plate and a thread tension spring in the lower thread bobbin housing portion. A tension generating portion for applying resistance to the lower thread drawn out of the lower thread bobbin, and an opening in front of a cut groove provided in the thread tension plate. From the part behind the cut groove and the A slit formed in the sliding plate in an oblique direction that bore the opposite direction, a sewing machine, characterized in that is provided.

The effects of the first technical means are as follows.

That is, since the lower thread can be set in the tension generating section only by guiding the lower thread along the slit provided in the slide plate, the lower thread can be easily set, and a separate member is not required. Lower thread can be supplied at cost. In addition, since the lower thread can be guided to the tension generating section in a state where the slide plate is opened, the inside of the lower thread bobbin accommodating port can be visually observed, and the state in which the lower thread is guided to the tension generating section can be visually observed.

In order to solve the above technical problem, the technical means (hereinafter referred to as second technical means) taken in claim 2 of the present invention is an end of the slit opposite to the opening. 2. The sewing machine according to claim 1, wherein the portion is provided with a curved portion bent in the direction of the needle hole.

The effects of the second technical means are as follows.

That is, since the lower thread can be guided in the direction of the needle hole along the curved portion, the size of the sliding plate can be reduced.

In order to solve the above technical problem, the technical means (hereinafter referred to as third technical means) taken in claim 3 of the present invention is an end of the slit opposite to the opening. The sewing machine according to claim 1 or 2, wherein a thread holding means for holding a lower thread is provided in the portion.

The effects of the third technical means are as follows.

That is, since the lower thread is held at the end of the slit, the lower thread is automatically and securely supplied to the tension generator when the sliding plate is closed.

In order to solve the above technical problem, the technical means (hereinafter referred to as the fourth technical means) taken in claim 4 of the present invention is provided when the slide plate is closed. 4. The sewing machine according to claim 3, further comprising a lower thread releasing mechanism for releasing the lower thread held by the thread holding means.

The effects of the fourth technical means are as follows.

That is, the lower thread is automatically disengaged from the thread holding means when the sliding plate is closed by the lower thread releasing mechanism, so that it is not necessary to manually remove the lower thread, thereby improving workability.

In order to solve the above technical problem, a technical means (hereinafter referred to as a fifth technical means) adopted in claim 5 of the present invention is that the lower thread releasing mechanism is provided with the yarn holding mechanism. A projection of the thread holding means provided so as to protrude from the sliding plate toward the needle hole side from a thread holding part provided in the means,
When the sliding plate is in the open state, a part of the convex portion is located above the back surface of the sliding plate, and a tip portion of the convex portion is provided with an inclined portion that is inclined below the back surface of the sliding plate. The sewing machine according to claim 4, characterized in that:

The effects of the fifth technical means are as follows.

That is, when the sliding plate is closed, the tip of the projection comes into contact with the upper surface of the bed, and the slant of the tip of the projection and the action of the upper surface of the bed release the thread holding portion of the thread holding means. The bobbin thread can be released with a simple structure, and a low-cost bobbin thread releasing mechanism can be provided.

[0027] In order to solve the above technical problem, the technical means (hereinafter referred to as sixth technical means) taken in claim 6 of the present invention is the one of the slit of the slit opposite to the opening. The sewing machine according to any one of claims 1 to 5, wherein a cutting unit that cuts a lower thread drawn from the lower thread bobbin is provided inside the bed unit near an end. .

The effects of the sixth technical means are as follows.

That is, since the cutting means is provided inside the bed near the end of the slit, the bobbin thread guided to the end can be easily cut without using a tool such as scissors.

In order to solve the above technical problem, the technical means (hereinafter referred to as seventh technical means) taken in claim 7 of the present invention is such that the cutting means is provided in the bed portion. The length of the bobbin thread from the tension generating section for applying tension to the bobbin thread provided in the bobbin case is provided at a position that is 4 to 20 mm longer than the length from the tension generating section to the needle hole. The sewing machine according to claim 6, wherein

The effects of the seventh technical means are as follows.

That is, since an appropriate amount of lower thread length is obtained after thread trimming, defective sewing due to the draw-out length can be prevented, and a beautiful stitch can be obtained from the first stitch at the start of sewing.

[0033]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described.
Description will be given based on the drawings. 1 is a schematic perspective view of the sewing machine of the embodiment, FIG. 2 is an exploded perspective view of an inner shuttle, FIG. 3 is a front view of the vicinity of a lower thread bobbin accommodating port with a sliding plate opened, as viewed from above the sewing machine, and FIG. Sectional view showing the engagement relationship between the sliding plate and the needle plate,
5 is a front view of the vicinity of the lower thread bobbin accommodating opening with the sliding plate closed, as viewed from above the sewing machine. FIG. 6 is a cross-sectional view taken along the line AA of FIG. 6 with the sliding plate opened. FIG. 8 is a cross-sectional view taken along line BB of FIG. 8 with the sliding plate opened, FIG. 9 is a cross-sectional view taken along line B′B of FIG. 9 with the sliding plate closed, and FIG. is there.

The present sewing machine comprises a bed 1a and a bed 1
1a, a pillar 1b integrally formed on the right side surface in FIG. 1 and standing upward, and an arm 1c extending horizontally from the pillar 1b above the bed 1a. It is configured. A needle bar 2 on which a needle 2a is mounted is provided at a tip of the arm portion 1c. The needle bar 2 is moved up and down by a drive mechanism (not shown) to perform sewing.

A needle plate 4 and a sliding plate 5 are provided on the upper surface 1d of the bed 1a at a portion where the needle 2a moves up and down.
A cutter 6 serving as a cutting means for cutting the lower thread is provided inside the bed 1a, and a gap 3 is provided on the upper surface 1d of the bed to allow the lower thread to be guided to the cutter 6.

The needle plate 4 is provided with a lower thread bobbin receiving port 4a for attaching and detaching the lower thread bobbin 14, and a needle hole 4b through which the needle 2a passes when the needle 2a moves up and down. An inner shuttle 7 is provided in a space inside the bed 1a below the needle plate 4, and the inner space of the inner shuttle 7 is a lower thread bobbin accommodating section 7b for detachably accommodating the lower thread bobbin. In the lower thread bobbin accommodation section 7b,
The tension generating unit 11 is provided to apply resistance to the lower thread drawn out from the lower thread bobbin 14.

The tension generator 11 is provided on the inner peripheral surface 7 of the inner hook 7.
The thread tension plate 8 and the thread tension spring 9 are attached to each other in a superposed state. The thread tension plate 8 has a cut groove 8a
The thread is guided between the thread tension plate 8 and the thread tension spring 9 by guiding the lower thread from the cut groove 8a to the groove 8b. And a tension suitable for sewing is given.

The sliding plate 5 includes the needle plate 4 and the lower thread bobbin receiving port 4a.
Is slidably opened and closed. The sliding plate 5 is configured to be opened in a direction opposite to the needle hole 4b provided in the needle plate 4, and becomes substantially flush with the needle plate 4, that is, the bed upper surface 1d when the sliding plate 5 is closed. Is configured.
The slide plate 5 and the needle plate 4 are connected by a guide rail. That is, the rail 16 is provided on the needle plate 4 and the sliding plate 5
Is provided with a guide portion 5h, and the rail 16 and the guide portion 5h are provided.
Are slidably fitted.

The sliding plate 5 has an end 5c on the needle hole 4b side.
Is provided with a slit 5a having an opening 5b.
The opening 5b is provided in front of the cut groove 8a in the direction in which the lower thread is led out from the lower thread bobbin 14, that is, on the right side of the cut groove 8a in FIG. The slit 5a is
A straight portion 5d provided obliquely from the opening 5b to the rear of the cut groove 8a (leftward in FIG. 3) and opposite to the needle hole 4b (downward in FIG. 3), and opposite to the opening 5b of the slit 5a. At the end of the needle hole 4b from the straight portion 5d.
It is composed of a curved portion 5e bent in the direction. In the case of the present embodiment, the curved portion 5e is bent in a semicircular shape.

When the lower thread comes to the end 5f of the slit 5a on the back surface of the sliding plate 5, a thread holding unit 1 for holding the lower thread is provided.
There is provided a thread holding leaf spring 15 which is a thread holding means having 5b. The thread holding leaf spring 15 is provided with a protruding portion 15a protruding from the end 5c of the sliding plate 5 closer to the needle hole 4b than the thread holding portion 15b. The protruding portion 15a is a lower thread releasing mechanism and is curved in a convex shape protruding upward. When the slide plate 5 is in the open state, the projection 15a is inclined so that a part thereof is above the back surface 5k of the slide plate 5 and the inclined portion 15d at the tip of the projection 15a is below the back surface 5k of the slide plate 5. It is provided.

A stopper 5i is provided on the back surface of the guide portion 5h of the sliding plate 5 to prevent the sliding plate 5 from falling off when the lower thread bobbin accommodating port 4a is opened. Rail 16
Is inverted downward in the direction of the needle plate 4, and a protruding positioning portion 16a is provided at the tip thereof. A first concave portion 5p and a second concave portion 5q that engage with the positioning portion 16a when the sliding plate 5 is opened and closed, respectively, are provided on the back surface of the guide portion 5h. The sliding plate 5 is provided with a sliding plate window 5g through which the remaining amount of the lower thread can be observed, and a hole 5j serving as a handle for manually opening and closing the sliding plate 5 is provided.

Bed 1 near end 5f of slit 5a
The cutter 6 is provided inside a. That is, the cutter 6 is provided inside the bed 1a opposite to the pillar 1b from the needle plate 4. The cutter 6 faces in the vertical direction in FIG. 3, and a blade is provided in the upper direction. The cutter 6 is covered with a cutter cover 6a. The cutter cover 6a is provided substantially flush with the bed 1a, and a gap 3 is provided between the cutter cover 6a and the bed 1a.

Next, the procedure for setting the lower thread by the user will be described. The user operates the sliding plate 5 from the opening direction. That is, the operation is performed on the near side in FIG.

First, the lower thread bobbin accommodation port 4a is opened, and the sliding plate 5 is slid to set the lower thread bobbin 14, thereby opening the lower thread bobbin accommodation port 4a. Sliding plate 5 is stopper 5i
Stops when it comes into contact with the side surface of the bed 1a. At this time, the positioning portion 16a of the rail 16 is engaged with the first concave portion 5p of the guide portion 5h, so that the slide plate 5 can be prevented from accidentally moving, and can be reliably stopped in the open state.

The lower thread bobbin 14 around which the lower thread is wound is set in the lower thread bobbin accommodating portion 7b. If the sliding plate 5 is not opened to the stopper position, the lower thread bobbin 14 is difficult to enter, so that the user can always open to the stopper position.

The user holds the end of the lower thread wound on the lower thread bobbin 14 by hand, pulls out the lower thread upward, and slides the opening 5b from the right side to the left side along the slit 5a. Move like that. When the lower thread is moved along the linear portion 5d of the slit 5a, the lower thread is automatically guided to the cut groove 8a of the tension generating section 11. Therefore, the setting of the lower thread is easy, and the slit 5a is provided on the existing sliding plate 5, so that the lower thread can be supplied at low cost without requiring a separate member.

Subsequently, when the lower thread is moved along the curved portion 5e of the slit 5a, the lower thread moves in the cut groove 8a. Since the lower thread can be largely moved in the direction of the needle plate 4 by the curved portion 5e, the sliding plate 5 can be made smaller.

When the lower thread comes near the end 5f of the slit 5a, the thread holding section 1 is actuated by the spring action of the thread holding leaf spring 15.
The lower thread is held between the sliding plate 5b and the sliding plate 5. Thereafter, the lower thread is moved toward the user and guided from the gap 3 to below the cutter cover 6a. Since the lower thread is held by the thread holding section 15b, the lower thread moves forward with the thread holding section 15b as a fulcrum, is cut by the cutter 6, and the extra thread is cut off. Since the bobbin thread can be cut by the cutter 6 in this manner, there is no need to use a tool such as scissors, and the work becomes easy. Further, since the lower thread is held by the thread holding portion 15b, no extra thread is pulled out from the lower thread bobbin 14 by the action of cutting the thread with the cutter 6, and the thread is set to an optimum length necessary at the start of sewing. Is cut off.

The position of the cutter 6 is provided at a position where the length of the cut lower thread from the tension generating section 11 can obtain a thread length necessary for forming the first stitch. That is, the position of the cutter 9d is provided such that the length of the thread is 4 to 20 mm longer than the length from the tension generating unit 11 to the needle hole 4b provided in the needle plate 4.

If the bobbin thread is too short, the first stitch is not formed and sewing cannot be performed. If the bobbin thread is too long, the thread will be entangled with the peripheral member, impairing the sewing machine function, or the bobbin thread will be sewn on the back of the cloth, failing to obtain a beautiful sewing finish. That is, since an appropriate amount of lower thread length can be obtained after thread trimming, it is possible to prevent poor sewing due to the draw-out length, and to obtain a beautiful stitch from the first stitch at the start of sewing.

Since the cutter 6 is covered with the cutter cover 6a, it is possible to prevent entry of anything other than the thread, and to secure the quality of the sewing product. Further, since the cutter cover 6a is provided substantially flush with the upper surface 1d of the bed portion, it does not hinder the sewing operation, is excellent in workability, and can secure the quality of the sewing product.

Next, the user slides and closes the slide plate 5. At this time, since the lower thread is still held by the thread holding portion 15b, the lower thread is moved forward and is automatically guided from the end of the cut groove 8a to the groove 8b. As a result, the bobbin thread is passed between the thread tension plate 8 and the thread tension spring 9 so that resistance is given by the scissoring force of the thread tension spring 9 and the thread is set in a state suitable for sewing.

When the sliding plate 5 is further closed, a part of the projecting portion 15a of the thread holding leaf spring 15 is located above the rear surface 5k of the sliding plate 5, and the inclined portion 15d of the projecting portion 15a is moved to the rear surface 5k of the sliding plate 5. Since the projection is inclined downward, the projection 15a comes into contact with the needle plate 4, and the projection 15a moves downward. When the sliding plate 5 is completely closed, the space between the thread holding portion 15b and the sliding plate 5 opens, and the lower thread is released from the thread holding portion 15b. This eliminates the need to manually remove the lower thread, thereby improving workability.

As described above, the user automatically draws the lower thread into the tension generating unit 11 by the operation of closing the slide plate 5, and
Preparation for sewing is completed. Thereby, the bobbin thread is guided into the minute slit 8a, which is troublesome when setting the bobbin bobbin 14, and the troublesome work of passing between the thread tension plate 8 and the thread tension spring 9 can be easily performed. The lower thread can be reliably set. Also, once the upper thread hooking is completed and the needle bar 2 is reciprocated once, the hook of the inner hook 7 catches the upper thread, passes through the inner hook 7 and lifts the lower thread, and the lower thread is inserted through the needle hole 4b. The bobbin thread can be set easily and securely without the troublesome work of pulling out the thread to a certain length.

[0055]

As described above, according to the present invention, a lower thread bobbin accommodating section provided in a bed section for detachably accommodating a lower thread bobbin, and an opening in the bed section for detachably operating the lower thread bobbin. A lower thread bobbin receiving port, which is provided in the lower thread bobbin receiving port, is substantially flush with the bed when closed, and is slidable in a direction opposite to a needle hole provided in the bed. A tension generating section configured to attach a thread tension plate and a thread tension spring to the lower thread bobbin accommodating section in a superposed state, and to apply resistance to a lower thread derived from the lower thread bobbin; A slit provided in the slide plate in an oblique direction that has an opening in front of the notch groove provided in the plate, is provided from the opening behind the notch groove, and in a direction opposite to the needle hole. Sewing machine characterized by Because, it is easy to set the lower thread to the tension generating unit, yet can provide a low cost of the sewing machine that can be visually observed how the lower thread is guided to the tension generating unit.

[Brief description of the drawings]

FIG. 1 is a schematic perspective view of a sewing machine according to an embodiment.

FIG. 2 is an exploded perspective view of an inner pot.

FIG. 3 is a front view of the vicinity of the lower thread bobbin accommodating opening with the sliding plate opened, as viewed from above the sewing machine.

FIG. 4 is a sectional view showing an engagement relationship between a slide plate and a needle plate.

FIG. 5 is a front view of the vicinity of the lower thread bobbin accommodating port with the sliding plate closed as viewed from above the sewing machine.

FIG. 6 is a sectional view taken along the line AA of FIG.

FIG. 7 is a sectional view taken along the line A′A ′ with the sliding plate closed.

FIG. 8 is a cross-sectional view of the BB with the sliding plate opened.

FIG. 9 is a sectional view taken along the line B′B ′ with the sliding plate closed.

FIG. 10 is a CC sectional view illustrating a cutting unit.

[Explanation of symbols]

 1a bed part 2a needle 4 needle plate 4a bobbin bobbin accommodating hole 4b needle hole 5 slide plate 5a slit 5b opening 5d linear part 5e curved part 5k back surface 6 cutter (cutting means) 7b ... lower thread bobbin accommodating section 8 ... thread tension plate 8a ... cut groove 9 ... thread tension spring 11 ... tension generating section 14 ... lower thread bobbin 15 ... thread retaining leaf spring (thread retaining means) 15a ... projection (convex) Section, lower thread release mechanism) 15b: thread holding section 15d: inclined section

Claims (7)

[Claims] 1. A lower thread bobbin receiving section provided in a bed section for detachably receiving a lower thread bobbin; a lower thread bobbin receiving port opened in the bed section for detachably operating the lower thread bobbin; A sliding plate provided in the lower thread bobbin receiving opening, which is substantially flush with the bed portion when closed, and which can be slidably opened and closed in a direction opposite to a needle hole provided in the bed portion; A tension generating portion that attaches a thread tension plate and a thread tension spring in a superimposed state to each other, and applies a resistance to a lower thread derived from the lower thread bobbin; and a cut-out groove provided in the thread tension plate. And a slit provided on the slide plate in an oblique direction from the opening behind the cut groove and in a direction opposite to the needle hole. 2. The sewing machine according to claim 1, wherein a curved portion bent in the direction of the needle hole is provided at an end of the slit opposite to the opening. 3. The sewing machine according to claim 1, wherein a thread holding means for holding a lower thread is provided at an end of the slit opposite to the opening. 4. The sewing machine according to claim 3, further comprising a lower thread releasing mechanism for releasing the lower thread held by the thread holding means when the slide plate is closed. 5. The thread lowering mechanism according to claim 5, wherein the lower thread releasing mechanism is a convex portion of the thread holding means provided to protrude from the sliding plate toward a needle hole from a thread holding portion provided in the thread holding means, When is in an open state, a part of the convex portion is above the rear surface of the sliding plate, and a tip portion of the convex portion is provided with an inclined portion that is inclined below the rear surface of the sliding plate. The sewing machine according to claim 4, wherein 6. A cutting means for cutting a lower thread pulled out from the lower thread bobbin is provided inside the bed portion, which is opposite to the opening and near an end of the slit. The sewing machine according to claim 1. 7. The bobbin case provided in the bed section, wherein a length of a bobbin thread from a tension generating section for applying a tension to a bobbin thread provided in the bed section is longer than a length from the tension generating section to the needle hole. The sewing machine according to claim 6, wherein the sewing machine is provided at a position where the length is 4 to 20 mm longer.