EMBROIDERY SEWING MACHINE AND METHOD

Abstract

An embroidery sewing machine includes a machine body carrying a needle, a shuttle and a bobbin. A cutter is disposed in proximity to the needle to cut a thread end portion of an upper thread that extends out of an eye of the needle so that the thread end portion has an adjusted length after being cut by the cutter. The needle, shuttle and bobbin are controlled to perform an initial stitching operation that pulls the thread end portion from an upper side of a fabric to an under side thereof and that produces a fixing stitch beneath the fabric to prevent the upper thread from being loosened. An embroidering method is also disclosed.

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates to a sewing machine, and more particularly to an embroidery sewing machine having a cutter and an embroidery sewing method using the sewing machine.

2. Description of the Related Art

Nowadays, most decorative embroidery patterns, which are formed conventionally by hand, have been made using embroidery sewing machines. However, most conventional embroidery sewing machines have a drawback in that a fabric embroidered thereby has an end portion of an upper thread, which extends out from an eye of a needle, and is usually left on an upper side of a fabric when an embroidery pattern is formed by the conventional embroidery sewing machines on the fabric. The end portion of the upper thread visible on the upper side of the fabric is detrimental to the aesthetic appearance of the embroidery pattern. While the thread end portion visible on the upper side of the fabric may be removed by cutting, the need to cut the thread end portion is time-consuming and inconvenient.

SUMMARY OF THE INVENTION

An object of the present invention is to provide an embroidery sewing machine that can pull a thread end portion of an upper thread from an upper side of a fabric to an under side of the fabric.

According to one aspect of the invention, an embroidering method is provided using an embroidery sewing machine, which includes a needle, a shuttle and a bobbin to operate upper and lower threads. The embroidering method comprises: (a) providing a cutter that is located at a predetermined distance from the needle to cut a thread end portion of an upper thread, which extends out from an eye of the needle, so that the thread end portion has an adjusted length; and (b) controlling the needle, the shuttle and the bobbin to operate the upper and lower threads to perform an initial stitching operation on a fabric for pulling the thread end portion from an upper side of the fabric to an under side of the fabric. The initial stitching operation includes the following sub-steps: (i) moving downward the needle from an uppermost point to a lowermost point wherein the thread end portion is pulled downward to the underside of the fabric, but a terminating end of the thread end portion is kept to remain on the upper side of the fabric; and (ii) moving upward the needle from the lowermost point to the uppermost point while operating the shuttle to pull and form the upper thread that passes through the fabric into a loop and to interlace the loop with the lower thread, wherein the terminating end of the thread end portion is pulled downward to the underside of the fabric.

According to another aspect of the invention, an embroidery sewing machine comprises: a machine body having a base, a support extending upward from the base, a sewing head suspended from the support, and a needle plate disposed on the base below the sewing head; a needle movably mounted to the sewing head and having an eye through which an upper thread passes; a shuttle unit mounted in the base; a bobbin disposed in the shuttle and holding a lower thread; and a cutter disposed in proximity to the needle to cut a thread end portion of the upper thread that extends out of the eye of the needle so that the thread end portion has an adjusted length after being cut by said cutter.

BRIEF DESCRIPTION OF THE DRAWINGS

Other features and advantages of the present invention will become apparent in the following detailed description of the preferred embodiments with reference to the accompanying drawings, of which:

FIG. 1 is a perspective view of a preferred embodiment of an embroidery sewing machine according to the present invention;

FIG. 2 is a fragmentary perspective view of the preferred embodiment;

FIG. 3 is a fragmentary elevation view of the preferred embodiment;

FIG. 4 is a block diagram illustrating how a shuttle and a bobbin are related to a drive unit and an electrical control; and

FIGS. 5-9 illustrates successive operating steps employed in an initial stitching operation for pulling a thread end portion of an upper thread from an upper side of a fabric to an under side of the fabric.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring to FIGS. 1-5, an embroidery sewing machine according to a preferred embodiment of the present invention may be used to form an embroidery pattern on a fabric 400 by operating an upper thread 200 and a lower thread 300. The embroidery sewing machine includes a machine body 1, a needle 2, a shuttle 31, a bobbin 32, a cutter 4, a drive unit 5 and an electrical control unit 6.

The machine body 1 has a base 11, an upstanding support 12 extending from the base 11, a sewing head 13 suspended from the support 12, and a needle plate 14.

The needle 2 is mounted on the sewing head 13 above the needle plate 14, and is movable upward and downward relative to the needle plate 14. The needle has an eye for passage of the upper thread 200.

The shuttle 31 is disposed rotatably in the base 11 below the needle plate 14. The bobbin 32 is disposed within the shuttle 31. The lower thread 300 is held within the bobbin 32 and has a portion extending outwardly from the bobbin 32.

The cutter 4 is installed on the sewing head 13 in proximity to the needle 2 and is used to cut a thread end portion 201 of the upper thread 200 that extends out of the eye of the needle 2. The cutter 4 has a cutter seat 41 mounted on the sewing head 13, and a cutter blade 42 mounted on the cutter seat 41. The cutter blade 42 is arranged to have a predetermined distance from the needle 2, which is about 4.5 cm. Therefore, when the thread end portion 201 of the upper thread 200 is pulled from the needle 2 to the cutter 4 and is cut by the cutter blade 42, the thread end portion 201 after being cut will have an adjusted length of about 4.5 cm.

While the cutter 4 is mounted on the sewing head 13 in this embodiment, it may also be mounted on any other suitable part of the machine body, which is proximate to the needle 2. The distance of the cutter 4 from the needle 2 may also be 4 cm, or 5 cm. Therefore, the distance of the cutter 4 is preferably in a range of 4-5 cm.

As shown in FIG. 4, the electrical control unit 6 is connected electrically to the drive unit 5, and the drive unit 5 is connected mechanically to the shuttle 31 and the bobbin 32. The drive unit 5 is controlled by the electrical control unit 6 to drive the shuttle 31 and the bobbin 32.

The embroidery sewing machine of the present invention may operate to pull down the thread end portion 201 from an upper side of the fabric 400 to an under side of the fabric 400. The needle 2, the shuttle 31 and the bobbin 32 may be controlled by the electrical control unit 6 to operate the upper and lower threads 200, 300 to perform an initial stitching operation for pulling the cut thread end portion 201 to the under side of the fabric 400. An embroidering method is exemplified below and includes steps (A) to (C).

Referring to FIG. 5, in step (A), the upper thread 200 is passed through an eye of the needle 2 and has the thread end portion 201 extending out of the eye of the needle 2 on the upper side of the fabric 400. The length of the thread end portion 201 is adjusted by cutting the thread end portion 201 using the cutter 4. The adjusted length of the thread end portion 201 is about 4.5 cm.

In step (B), the needle 2, the shuttle 31 and the bobbin 32 are controlled by the drive unit 5 and the electrical control unit 6 to operate the upper and lower threads 200, 300 to perform an initial stitching operation on the fabric 400 for pulling the thread end portion 201 from an upper side of the fabric 400 to an under side of the fabric 400. The initial stitching operation including the following sub-steps:

(b-1) The needle 2 is moved downward from an uppermost point to a lowermost point through the fabric 400 and pulls the thread end portion 201 to the under side of the fabric 400. But, a terminating end of the thread end portion 201 is kept to remain on the upper side of the fabric 400.

(b-2) Referring to FIGS. 6, 7 and 8, the needle is moved upward from the lowermost point toward the uppermost point while the shuttle 31 is being operated to pull and form the upper thread 200 that passes through the fabric 400 into a loop 202 and to interlace the loop 202 with the lower thread 300. In particular, the upper and lower threads 200, 300 are interlaced by causing the loop 202 of the upper thread 200 to loop around the lower thread 300. During the upward movement of the needle 2, the upper thread 200 is pulled and the loop 202 is tightened gradually. When the needle 2 reaches the uppermost point, the loop 202 is formed into a tightened knot 203, and the terminating end of the thread end portion 201 is completely pulled downward to the underside of the fabric 400.

Referring to FIG. 9, in step (C), the downward and upward movements of the needle 2 carried out in step (B) are repeated at least twice to interlace and form the upper and lower threads 200, 300 into a fixing stitch 204 that fixes the upper thread 200 to the fabric 400 so that the upper thread 200 is prevented from becoming loosened.

Because the thread end portion 201 is hidden beneath the fabric 400, it does not affect the aesthetic appearance of the embroidery pattern formed at the upper side of the fabric 400. Therefore, it is not necessary to cut the thread end portion 201 of the upper thread from the fabric 400.

While the present invention has been described in connection with what is considered the most practical and preferred embodiments, it is understood that this invention is not limited to the disclosed embodiment but is intended to cover various arrangements included within the spirit and scope of the broadest interpretation so as to encompass all such modifications and equivalent arrangements.

Claims

1. An embroidering method using an embroidery sewing machine, which includes a needle, a shuttle and a bobbin to operate upper and lower threads, the embroidering method comprising:

(a) providing a cutter that is located at a predetermined distance from the needle to cut a thread end portion of an upper thread, which extends out from an eye of the needle, so that the thread end portion has an adjusted length;

(b) controlling the needle, the shuttle and the bobbin to operate the upper and lower threads to perform an initial stitching operation on a fabric for pulling the thread end portion from an upper side of the fabric to an under side of the fabric, the initial stitching operation including the following sub-steps: (i) moving downward the needle from an uppermost point to a lowermost point wherein the thread end portion is pulled downward to the underside of the fabric, but a terminating end of the thread end portion is kept to remain on the upper side of the fabric; and (ii) moving upward the needle from the lowermost point to the uppermost point while operating the shuttle to pull and form the upper thread that passes through the fabric into a loop and to interlace the loop with the lower thread, wherein the terminating end of the thread end portion is pulled downward to the underside of the fabric.

2. The embroidering method of claim 1, wherein the upper and lower threads are interlaced by causing the loop of the upper thread to loop around the lower thread and by tightening the loop during the upward movement of the needle to reach the uppermost point.

3. The embroidering method of claim 2, wherein the sub-steps (i) and (ii) is repeated at least twice to interlace the upper and lower threads to form a fixing stitch that fixes the upper thread to the fabric.

4. The embroidering method of claim 1, wherein the predetermined distance of the cutter from the needle is 4-5 cm.

5. An embroidery sewing machine comprising:

a machine body having a base, a support extending upward from said base, a sewing head suspended from said support, and a needle plate disposed on said base below said sewing head;

a needle movably mounted to said sewing head and having an eye through which an upper thread passes;

a shuttle unit mounted in said base;

a bobbin disposed in said shuttle and holding a lower thread; and

a cutter disposed in proximity to said needle to cut a thread end portion of said upper thread that extends out of said eye of said needle so that said thread end portion has an adjusted length after being cut by said cutter.

6. The embroidery sewing machine as claimed in claim 5, wherein said cutter includes a cutter seat mounted to said sewing head, and a cutting blade mounted to said cutter seat.

7. The embroidery sewing machine as claimed in claim 6, wherein a distance of said cutter from said needle is about 4-5 cm so that said thread end portion has a length of about 4-5 cm after being cut by said cutter.

8. The embroidery sewing machine as claimed in claim 5, further comprising an electrical control unit, and a drive unit controlled by said electrical control unit to operate said shuttle and said bobbin.

9. The embroidery sewing machine as claimed in claim 8, wherein said needle, said shuttle and said bobbin are operated by said drive unit to perform an initial stitching operation, during which: said needle is moved downward from an uppermost point to a lowermost point; said thread end portion is pulled downward to the underside of the fabric while a terminating end of said thread end portion is being kept to remain on the upper side of the fabric; and when said needle moves upward from the lowermost point to the uppermost point, said shuttle is operated to pull and form said upper thread that passes through the fabric into a loop around said lower thread, and the terminating end of said thread end portion is pulled downward to the underside of the fabric.