JP5439027B2 - Upper thread changing device of sewing machine - Google Patents

Description

  The present invention relates to an upper thread changing apparatus for a sewing machine, and more particularly to an upper thread changing apparatus for a sewing machine that can shorten the thread replacement time and increase the productivity.

  As a conventional sewing machine, for example, as shown in FIG. 11 and FIG. 12, one having an upper thread adjuster 102 in which one upper thread 107 a is inserted and the tension of the upper thread 107 a is adjusted is generally known. In this sewing machine 101, an upper thread 107a (for example, a brown upper thread) fed from a core winding portion 107 is passed through an upper thread adjuster 102, a balance 115, a thread guide 116, and a needle hole 117 in this order. An end of a replacement upper thread 110 a (for example, a black upper thread) fed out from the section 110 is temporarily fixed by a magnet 112 or the like in front of the upper thread adjuster 102.

  As the above-described conventional method for replacing the upper thread of the sewing machine, for example, the old thread 107a inserted into the upper thread adjuster 102 is cut before (upstream side) the upper thread adjuster 102, and then the old thread 107a is cut. The thread and the end of the new thread 110a, and then pass the tied thread through the upper thread adjuster 102, the balance 115 and the thread guide 116, and then cut the knot before the needle hole 117, It is known to pass the cutting portion of the new thread 110a through the needle hole 117 and complete the thread exchange. Patent Document 1 discloses a method of automatically tying an old yarn and a new yarn by a yarn joining device regardless of the operator's hand.

  However, in the above-described conventional method for replacing the upper thread of the sewing machine, the old thread 107a and the new thread 110a are tied before the upper thread regulator 102, the tied thread is passed through the upper thread regulator 102, and before the needle hole 117. Since it is necessary to cut the yarn tied with the yarn, it takes a long time to replace the yarn, resulting in low productivity.

Japanese Patent Laying-Open No. 2005-230477

  The present invention has been made in view of the above situation, and an object of the present invention is to provide an upper thread changing device for a sewing machine that can shorten the time for replacing the thread and increase the productivity.

The present invention is as follows.
1. An upper thread adjuster in which a plurality of upper threads are inserted and the tension of the plurality of upper threads can be adjusted;
An upper thread selection which is arranged in an upper thread path between the upper thread adjuster and the needle hole, selectively releases at least one upper thread of the plurality of upper threads and locks the other upper thread A mechanism ,
The upper thread selection mechanism includes a first member formed with a plurality of first thread passage holes through which the plurality of upper threads pass, a relative movement with the first member, and each of the plurality of upper threads. A second member formed with a plurality of second thread passage holes through which the plurality of first thread passage holes and the second thread passage holes are moved by relative movement of the first member and the second member. The first yarn passage hole and the second yarn passage hole that are at least one pair of the two overlap, and the first yarn passage hole and the second yarn passage hole that are the other pair do not overlap, and the other pair An upper thread changing device for a sewing machine, wherein the upper thread passing through the first upper thread passing hole and the second upper thread passing hole is locked between the first member and the second member .
2. The first member is an outer pipe, the second member is an inner rod slidable in the axial direction in the outer pipe, and the plurality of first thread passage holes are formed in the outer pipe along the axial direction. The plurality of second thread passage holes are formed in the inner rod along the axial direction . The upper thread changing device of the described sewing machine.
3. The inner rod has a large-diameter portion having an outer peripheral surface for sandwiching the upper thread with the inner peripheral surface of the outer pipe, and the second thread passage hole is connected to both axial ends of the large-diameter portion. And 2. the formed small diameter portion . The upper thread changing device of the described sewing machine.

According to the upper thread changing device of the sewing machine of the present invention, a plurality of upper threads are inserted into the upper thread adjuster, and at least one upper thread of the plurality of upper threads is selectively released by the upper thread selecting mechanism. And the other upper thread is locked. Thus, on the downstream side of the upper thread adjuster, a desired upper thread of a plurality of upper threads fed from the upper thread adjuster is selectively released and other unselected upper threads are locked. Therefore, it is not necessary to tie the new thread to the old thread to pass the upper thread regulator, to pass the upper thread regulator, or to cut the knot before the needle hole. Therefore, it is possible to shorten the yarn exchange time and increase productivity.
The upper thread selection mechanism includes a first member formed with a plurality of first thread passage holes through which the plurality of upper threads pass, and a plurality of upper threads that are movable relative to the first member. A second member formed with a plurality of second thread passage holes through which the plurality of first thread passage holes and the second thread are moved by relative movement of the first member and the second member. The first yarn passage hole and the second yarn passage hole that form at least one pair of the passage holes overlap, and the first yarn passage hole and the second yarn passage hole that constitute another pair do not overlap, and the other since locking the yarn between the first member and the second member on through the first needle thread passing hole and the second needle thread passing hole a pair of, first yarn comprising at least one pair are superimposed to each other The upper yarn passing through the passage hole and the second yarn passage hole is released, and the first yarn passage hole and the other pair which are not overlapped with each other Upper thread through the second thread passage hole is locked between the first and second members. As a result, the upper thread changing device can have a simple and inexpensive structure.
The first member is an outer pipe, and the second member is an inner rod slidable in the outer pipe in the axial direction. The outer pipe includes the plurality of first threads along the axial direction. When the plurality of second thread passage holes are formed along the axial direction in the inner rod, the passage holes are formed, and the inner pipes are overlapped with each other by the relative sliding movement of the outer pipe and the inner rod. The upper yarn passing through at least one pair of the first yarn passage hole and the second yarn passage hole is released, and passes through the other first yarn passage hole and second yarn passage hole that do not overlap each other. The upper thread is locked between the outer pipe and the inner rod. Since the locked upper thread is housed in a folded shape in the outer pipe, it is possible to prevent the cut end from being sufficiently away from the needle hole and hindering a sewing operation using the released upper thread.
Further, the inner rod is connected to the large-diameter portion having an outer peripheral surface sandwiching the upper thread between the inner peripheral surface of the outer pipe and the second yarn passing through the both ends in the axial direction of the large-diameter portion. A small-diameter portion with a hole formed therein, the upper thread can be clamped by the outer pipe and the inner rod to the minimum length, and damage due to the upper thread can be suppressed. .

The present invention will be further described in the following detailed description with reference to the drawings referred to, with reference to non-limiting examples of exemplary embodiments according to the present invention. Similar parts are shown throughout the several figures.
It is a front view which shows the whole sewing machine which concerns on an Example. It is a front view of the upper thread regulator which concerns on an Example. It is a perspective view which shows the assembly | attachment state of the said upper thread regulator. It is a perspective view which shows the decomposition | disassembly state of the said upper thread regulator. It is a longitudinal cross-sectional view which shows the 1st thread | yarn release state of the upper thread | yarn selection mechanism which concerns on an Example. It is a longitudinal cross-sectional view which shows the 2nd thread | yarn release state of the said upper thread | yarn selection mechanism. It is a perspective view which shows the assembly | attachment state of the said upper thread selection mechanism. It is a perspective view which shows the decomposition | disassembly state of the said upper thread selection mechanism. It is explanatory drawing for demonstrating the upper thread selection mechanism of another form. Furthermore, it is explanatory drawing for demonstrating the upper thread selection mechanism of another form. It is explanatory drawing for demonstrating the thread | yarn exchange method of the conventional sewing machine. It is a principal part enlarged view of FIG.

  The items shown here are exemplary and illustrative of the embodiments of the present invention, and are the most effective and easy-to-understand explanations of the principles and conceptual features of the present invention. It is stated for the purpose of providing what seems to be. In this respect, it is not intended to illustrate the structural details of the present invention beyond what is necessary for a fundamental understanding of the present invention. It will be clear to those skilled in the art how it is actually implemented.

1. Upper thread changing device of sewing machine Embodiment 1 The upper thread changing device of the sewing machine includes an upper thread adjuster and an upper thread selecting mechanism described below.

  The “upper thread adjuster” is not particularly limited in its configuration, tension adjustment form, installation form, and the like as long as a plurality of upper threads are inserted and tensions of the plurality of upper threads can be adjusted. On the downstream side of the upper thread regulator, for example, a balance and a thread guide through which the upper thread fed from the upper thread regulator is passed can be sequentially provided.

  The “upper thread selection mechanism” is disposed in the upper thread path between the upper thread adjuster and the needle hole, selectively releases at least one upper thread of the plurality of upper threads, and As long as the yarn is locked, its configuration, selection mode, installation mode, etc. are not particularly limited. The upper thread selection mechanism can be disposed, for example, in an upper thread path between the thread guide and the needle hole. As a result, the upper thread can be replaced without requiring the operation of passing the upper thread through the balance and the thread guide in addition to the upper thread adjuster, and the time can be further shortened. The “selective” is intended to select any one or more upper threads from a plurality of upper threads. The “other upper thread” means an upper thread other than the selectively released upper thread among a plurality of upper threads.

  Embodiment 1 As an upper thread changing device of the sewing machine, for example, the upper thread selecting mechanism includes a first member in which a plurality of first thread passage holes for passing each of a plurality of upper threads are formed, and a relative to the first member. And a second member formed with a plurality of second thread passage holes through which each of the plurality of upper threads is passed, and the plurality of first members are moved by relative movement of the first member and the second member. A first yarn passing hole and a second yarn passing hole which overlap with at least one pair of the first yarn passing hole and the second yarn passing hole of the yarn passing hole and the second yarn passing hole, and which are another pair. The upper thread which passes through the first upper thread passage hole and the second upper thread passage hole which form the other pair does not overlap, and the first member and the second member are locked. The plurality of first yarn passage holes and the second yarn passage holes are usually provided in the same number so that each one is paired. Moreover, as a movement form of these 1st and 2nd members, 1 type, or 2 or more types of combinations among slide movement, rotation movement, turning movement, etc. can be mentioned, for example. In addition, the above “pairing” intends the first yarn passage hole and the second yarn passage hole through which the same upper thread is passed.

  In the case of the above-described form, for example, the first member is an outer pipe, the second member is an inner rod that can slide in the outer pipe in the axial direction, and the outer pipe includes a plurality of pieces along the axial direction. The first thread passage hole is formed, and the inner rod can be formed with a plurality of second thread passage holes along the axial direction. These first thread passage holes are usually provided so as to penetrate the upper and lower surfaces of the outer pipe. Further, an axial separation interval (L1) between two adjacent first yarn passage holes among the plurality of first yarn passage holes is, for example, two adjacent ones of the plurality of second yarn passage holes. It can be set to a value smaller than the spacing distance (L2) in the axial direction of the second yarn passage hole (see, for example, FIG. 5). Thereby, the upper thread accommodated in the folded shape in the outer pipe can be made longer, and it is possible to more reliably prevent the sewing work from being hindered. The said space | interval (L1) can be 15-25 mm (preferably 18-20 mm), for example. Moreover, the said space | interval (L2) can be 65-75 mm, for example. Furthermore, the ratio (L1 / L2) between the separation interval (L1) and the separation interval (L2) may be 0.23 to 0.33, for example.

  The inner rod has, for example, a large-diameter portion having an outer peripheral surface that sandwiches the upper thread with the inner peripheral surface of the outer pipe, and a second thread passage hole that is connected to both axial ends of the large-diameter portion. A small diameter portion. This large diameter part can be formed in the size which can block the 1st thread passage hole of an outside pipe, for example.

  Hereinafter, the present invention will be specifically described with reference to the drawings.

(1) Configuration of Upper Thread Exchanger As shown in FIG. 1, the sewing machine 1 according to this embodiment includes a yarn changer 4 having an upper thread adjuster 2 and an upper thread selection mechanism 3. Further, on the lower side of the sewing table 6 of the sewing machine 1, a pair of core winding portions 7, 8 formed by winding a predetermined upper thread 7a, 8a (for example, a brown upper thread) and other predetermined ( For example, a pair of core winding portions 10 and 11 formed by core winding upper yarns 10a and 11a of black upper thread) are juxtaposed along the left-right direction of the sewing machine 1 so as to be adjacent to each other. The upper thread 7a fed out from one core winding part 7 of the pair of core winding parts 7 and 8 includes a threading pipe 13, an upper thread adjuster 2, a balance 15, a thread guide 16, the upper thread selection mechanism 3, and a needle. The holes 17 are passed through in this order. The end of the upper thread 7a of one core winding part 7 is tied to the beginning of the upper thread 8a of the other core winding part 8. Further, the upper thread 10a fed out from one core winding part 10 of the pair of core winding parts 10 and 11 includes a threading pipe 14, an upper thread adjuster 3, a balance 15, a thread guide 16, and an upper thread selection mechanism 3. It is passed in the order. The end of the upper thread 10a of one core winding part 10 is tied to the beginning of the upper thread 11a of the other core winding part 11.

  The upper thread adjuster 2 is attached to the front side of the sewing machine arm 1a by a mounting plate 20 (see FIG. 1). As shown in FIGS. 2 to 4, the upper thread adjuster 2 includes an adjusting unit 21 a for adjusting the tension of the upper thread 7 a through which the upper thread 7 a is inserted, and the tension of the upper thread 10 a through which the upper thread 10 a is inserted. And an adjusting portion 21b for adjusting the angle. Each of these adjusting portions 21a and 21b provides pretensioners 22a and 22b for adjusting the remaining lengths of the upper threads 7a and 10a after thread trimming, and provides tension necessary for stitch formation and the upper thread feed amount. The upper thread retainers 23a and 23b to be adjusted, the thread take-up spring 24 for adjusting the upper thread feed amount, and support plates 25a and 25b for supporting the thread take-up spring 24 are provided.

  The upper thread selection mechanism 3 is disposed in the upper thread path between the thread guide 16 and the needle hole 17 (see FIG. 1). As shown in FIGS. 5 to 8, the upper thread selection mechanism 3 includes a cylindrical outer pipe 27 having an outer diameter of about 14 mm and an inner diameter of about 8 mm attached to the front side of the sewing machine arm 1 a, And an inner rod 28 slidable in the axial direction. The inner rod 28 is connected to a large-diameter portion 29 having an outer peripheral surface that sandwiches the upper threads 7a, 10a with the inner peripheral surface of the outer pipe 27, and is connected to both ends in the axial direction of the large-diameter portion 29, which will be described later. And small diameter portions 30a and 30b in which second thread passage holes are formed. The large-diameter portion 29 has an outer diameter of about 7.5 mm and an axial length of about 11 mm. The large-diameter portion 29 closes a first thread passage hole to be described later. It has become. Moreover, the outer diameter of each small diameter part 30a, 30b is about 6.5 mm. A large-diameter portion 31 for attaching the operation lever 33 is provided on one end side of one small-diameter portion 30b. The operation lever 33 is attached to the large-diameter 31 portion of the inner rod 28 through an axially extending long hole 32 formed on the outer peripheral side of the outer pipe 27 (see FIGS. 7 and 8).

  The outer pipe 27 is formed with two first thread passage holes 34 and 35 that are spaced apart in the axial direction. These first yarn passage holes 34 and 35 are provided through the upper and lower surfaces of the outer pipe 27. The upper thread 7 a is passed through one first thread passage hole 34, and the upper thread 10 a is passed through the other first thread passage hole 35. The distance L1 between the first yarn passage holes 34 and 35 in the axial direction is about 20 mm (see FIG. 5). The inner rod 28 is formed with two second thread passage holes 37 and 38 that are spaced apart in the axial direction. The upper thread 7 a is passed through one second thread passage hole 37, and the upper thread 10 a is passed through the other second thread passage hole 38. The distance L2 in the axial direction of each of the second thread passage holes 37 and 38 is about 65 mm (see FIG. 5). Therefore, the ratio (L1 / L2) of the separation interval L1 between the first yarn passage holes 34 and 35 and the separation interval L2 between the second yarn passage holes 37 and 38 is about 0.31. Moreover, the hole diameter of each 1st thread | yarn passage hole 34 and 35 is about 7 mm, and the hole diameter of each 2nd thread | yarn passage hole 37 and 38 is about 6 mm. In the upper thread selection mechanism 3, the first thread release that releases the upper thread 7a and locks the upper thread 10a by operating the operation lever 33 and sliding the inner rod 28 relative to the outer pipe 27 is performed. The state P (see FIG. 5) and the second thread release state Q (see FIG. 6) in which the upper thread 7a is locked and the upper thread 10a is released can be selected.

(2) Operation of Upper Thread Exchanger Next, the operation of the above-described upper yarn changer 4 will be described. When the inner rod 28 is slid with respect to the outer pipe 27 by the operation of the operation lever 33 and the upper thread selection mechanism 3 is set to the first thread release state P, as shown in FIG. 34 and the second thread passage hole 37 overlap, and the upper thread 7a passing through the first and second thread passage holes 34, 37 is movable in the vertical direction and released. Further, the pair of the first yarn passage hole 35 and the second yarn passage hole 38 do not overlap, and the first yarn passage hole 35 is closed by the large diameter portion 29 of the inner rod 28. Further, the upper thread 10a passing through the first and second thread passage holes 35 and 38 is pinched between the inner peripheral surface of the outer pipe 27 and the outer peripheral surface of the large-diameter portion 29 of the inner rod 28 so as to be locked. Is done. Further, the sliding movement of the inner rod 28 relative to the outer pipe 27 is restricted by the lock of the upper thread 10a.

  On the other hand, when the upper rod selection mechanism 3 is brought into the second thread release state Q by sliding the inner rod 28 relative to the outer pipe 27 by operating the operation lever 33, as shown in FIG. The passage hole 35 and the second thread passage hole 38 are overlapped, and the upper thread 10a passing through the first and second thread passage holes 35, 38 is movable in the vertical direction and released. Further, the pair of the first yarn passage hole 34 and the second yarn passage hole 37 do not overlap, and the first yarn passage hole 34 is closed by the large diameter portion 29 of the inner rod 28. Further, the upper thread 7a passing through the first and second thread passage holes 34 and 37 is pinched and locked between the inner peripheral surface of the outer pipe 27 and the outer peripheral surface of the large-diameter portion 29 of the inner rod 28. Is done. Furthermore, the sliding movement of the inner rod 28 relative to the outer pipe 27 is restricted by the lock of the upper thread 7a.

  Next, an operation of replacing the upper thread 7a (old thread) in use with the upper thread 10a (new thread) to be used by using the upper thread changing device 4 will be described. First, the upper thread 7a is cut in the vicinity of the needle hole 17 by a known automatic thread cutting device (not shown). Next, the upper rod selection mechanism 3 is changed from the first yarn release state P to the second yarn release state Q by sliding the inner rod 28 relative to the outer pipe 27 by operating the operation lever 33. Then, the cut upper thread 7a is housed in the outer pipe 27 and locked. On the other hand, the upper thread 10a is unlocked and can move up and down, and the portion housed in the outer pipe 27 is pulled out, and the tip of the upper thread 10a is positioned near the needle hole 17. Thereafter, the tip of the upper thread 10a is passed through the needle hole 17, and the series of upper thread replacement operations is completed.

(3) Effects of the Embodiment As described above, according to the upper thread changing device 4 of the present embodiment, the two upper threads are inserted into the upper thread adjuster 2, and one upper thread 7a is moved by the upper thread selecting mechanism 3. A first thread releasing state P in which the upper thread 10a is released and the other upper thread 10a is locked and a second thread releasing state Q in which one upper thread 7a is locked and the other upper thread 10a is released can be selected. Therefore, it is not necessary to tie the new thread to the old thread to pass the upper thread adjuster, to pass the upper thread adjuster, or to cut the knot before the needle hole as in the prior art. Therefore, it is possible to shorten the yarn exchange time and increase productivity. In particular, in the present embodiment, the upper thread selection mechanism 3 is disposed in the upper thread path between the thread guide 16 and the needle hole 17, so that the upper thread is also applied to the balance 15 and the thread guide 16 in addition to the upper thread regulator 2. The upper thread can be exchanged without requiring the operation of passing through 7a and 10a, and the time can be further reduced.

  Further, in this embodiment, the upper thread selection mechanism 3 is slid in the axial direction within the outer pipe 27 in which the two first thread passage holes 34 and 35 are formed apart from each other in the axial direction. The upper thread exchanging device 4 has a simple and inexpensive structure because it is configured to include the inner rod 28 formed with two second thread passage holes 37 and 38 that are separated in the axial direction. be able to. Further, in each of the first thread release state P and the second thread release state Q, the upper threads 7 a and 10 a that are locked between the outer pipe 27 and the large-diameter portion 29 of the inner rod 28 are within the outer pipe 27. Since the folded end is stored, it is possible to prevent the cut end from being sufficiently separated from the needle hole 17 and hindering a sewing operation using the released upper thread. In particular, in this embodiment, the separation interval L1 between the first yarn passage holes 34 and 35 is about 20 mm, the separation interval L2 between the second yarn passage holes 37 and 38 is about 65 mm, and the ratio (L1 / L2) between them is set. Since 0.31 is set, the upper threads 7a and 10a accommodated in the outer pipe 27 in a folded shape can be made longer, and the sewing work can be more reliably prevented from being hindered.

  Further, in the present embodiment, the inner rod 28 is disposed on the both ends of the large diameter portion 29 in the axial direction, and a large diameter portion 29 having an outer peripheral surface that sandwiches the upper thread with the inner peripheral surface of the outer pipe 27. And the small diameter portions 30a and 30b in which the second thread passage holes 37 and 38 are formed in succession. Therefore, the holding portion of the upper threads 7a and 10a by the outer pipe 27 and the inner rod 28 is set to a minimum length. Thus, it is possible to suppress damage and the like due to the pinching of the upper threads 7a and 10a.

In the present invention, the present invention is not limited to the above embodiment, and various modifications can be made within the scope of the present invention depending on the purpose and application. That is, in the above embodiment, the upper threads 7a and 10a are released and locked between the outer pipe 27 and the inner rod 28 by the sliding movement of the inner rod 28 with respect to the outer pipe 27 . As a reference example , for example, a form in which the upper threads 7a and 10a are released and locked by a clamp device driven by a drive source (for example, a motor, a cylinder, etc.) can be cited .

  In the above embodiment, the upper thread selection mechanism 3 is configured by slidably supporting the inner rod 28 in the outer pipe 27. However, the upper thread selection mechanism 3 is not limited to this. For example, as shown in FIG. An upper thread selection having a base member 40 in which passage holes 34 and 35 are formed and a slide member 41 that is slidably supported on the surface side of the base member 40 and in which second thread passage holes 37 and 38 are formed. For example, as shown in FIG. 10, a base member 43 in which first thread passage holes 34 and 35 are formed, and a second thread supported by the base member 43 so as to be rotatable about a vertical axis. An upper thread selection mechanism 3 ″ having a rotation member 44 in which passage holes 37 and 38 are formed may be used.

  In the above embodiment, the outer pipe 27 is fixed to the front side of the sewing machine arm 1a, and the inner rod 28 is slid relative to the outer pipe 27. However, the present invention is not limited to this. May be fixed to the front side of the sewing machine arm 1a, and the outer pipe 27 may be slid relative to the inner load 28.

  Furthermore, in the above-described embodiment, the upper thread adjuster 2 through which the two upper threads 7a and 10a are inserted is illustrated, but the present invention is not limited to this. For example, the upper thread adjuster through which three or more upper threads are inserted It is good also as a vessel. In this case, as the upper thread selection mechanism, one that releases one upper thread of three or more upper threads and locks the other two or more upper threads, or employs three or more upper threads. It is possible to employ one that releases two or more upper threads and locks one or more other upper threads.

  The foregoing examples are for illustrative purposes only and are not to be construed as limiting the invention. Although the invention has been described with reference to exemplary embodiments, it is to be understood that the language used in the description and illustration of the invention is illustrative and exemplary rather than limiting. As detailed herein, changes may be made in its form within the scope of the appended claims without departing from the scope or spirit of the invention. Although specific structures, materials, and examples have been referred to in the detailed description of the invention herein, it is not intended to limit the invention to the disclosure herein, but rather, the invention is claimed. It covers all functionally equivalent structures, methods and uses within the scope of.

  The present invention is not limited to the embodiments described in detail above, and various modifications or changes can be made within the scope of the claims of the present invention.

  It is widely used as a technique for replacing the upper thread of a sewing machine.

  DESCRIPTION OF SYMBOLS 1; Sewing machine, 2; Upper thread regulator, 3, 3 ', 3 "; Upper thread selection mechanism, 4; Upper thread changer, 7a, 10a; Upper thread, 17; Needle hole, 27; Outer pipe, 28; Inner rod, 29; large diameter portion, 30a, 30b; small diameter portion, 34, 35; first thread passage hole, 37, 38; second thread passage hole.

Claims (3)

An upper thread adjuster in which a plurality of upper threads are inserted and the tension of the plurality of upper threads can be adjusted;
An upper thread selection which is arranged in an upper thread path between the upper thread adjuster and the needle hole, selectively releases at least one upper thread of the plurality of upper threads and locks the other upper thread A mechanism ,
The upper thread selection mechanism includes a first member formed with a plurality of first thread passage holes through which the plurality of upper threads pass, a relative movement with the first member, and each of the plurality of upper threads. A second member formed with a plurality of second thread passage holes through which the plurality of first thread passage holes and the second thread passage holes are moved by relative movement of the first member and the second member. The first yarn passage hole and the second yarn passage hole that are at least one pair of the two overlap, and the first yarn passage hole and the second yarn passage hole that are the other pair do not overlap, and the other pair An upper thread changing device for a sewing machine, wherein the upper thread passing through the first upper thread passing hole and the second upper thread passing hole is locked between the first member and the second member . The first member is an outer pipe, the second member is an inner rod slidable in the axial direction in the outer pipe, and the plurality of first thread passage holes are formed in the outer pipe along the axial direction. The upper thread changing device of a sewing machine according to claim 1, wherein the plurality of second thread passage holes are formed in the inner rod along the axial direction . The inner rod has a large-diameter portion having an outer peripheral surface for sandwiching the upper thread with the inner peripheral surface of the outer pipe, and the second thread passage hole is connected to both axial ends of the large-diameter portion. The upper thread changing device of a sewing machine according to claim 2 , further comprising a formed small diameter portion .

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