WO2014192179A1

WO2014192179A1 - Sewing machine and needle bar

Info

Publication number: WO2014192179A1
Application number: PCT/JP2013/078024
Authority: WO
Inventors: 康次宮地
Original assignee: ハムス株式会社
Priority date: 2013-05-31
Filing date: 2013-10-16
Publication date: 2014-12-04
Also published as: TW201445018A; JP5632949B1; JP2015006309A; KR20160014120A; CN104364432A

Abstract

The purpose of the present invention is to provide a sewing machine which has a simple structure and is capable of neatly finishing a seam when sewing a workpiece while tracing a curve. Provided is a sewing machine (1) provided with a sewing machine body (10), a needle bar (20) provided in the sewing machine body (10), and a sewing needle (30) held in the needle bar (20), the needle bar (20) and the sewing needle (30) making a vertical reciprocating motion relative to the sewing machine body (10). The needle bar (20) is separately composed of a tip-side needle bar (21) for holding the sewing needle on an axis of the vertical reciprocating motion and a base-end-side needle bar (22) provided in the sewing machine body (10) on the axis, the tip-side needle bar (21) rotating on its axis around the axis of the vertical reciprocating motion relative to the base-end-side needle bar (22).

Description

Sewing machine and needle bar

The present invention relates to a sewing machine used when sewing a workpiece such as synthetic leather, leather, and cloth mainly for industrial use, and a needle bar used for the sewing machine.

Generally, a sewing machine includes a sewing machine body, a needle bar provided on the sewing machine body, a sewing needle held by the needle bar, a hook that receives the sewing needle, and a feed mechanism that feeds the cloth. Is configured to reciprocate up and down by a drive motor or the like. The needle thread and sewing needle are reciprocated up and down with respect to the hook while manually or automatically feeding workpieces such as synthetic leather, leather, and cloth by the feed mechanism, and the upper thread passed through the sewing needle And the lower thread passed through the hook are sewn on the workpiece.

By the way, recently, special-purpose workpieces such as automobile airbags and seats have been sewn, but these special-purpose workpieces are not straight but curved, such as a circle. Often drawn.

However, when a workpiece is sewed while drawing a curve in this way, the sewing direction and the thread direction are different in the sewing process, so the upper thread passed through the needle hole of the sewing needle comes into contact with the sewing needle. Unnecessary resistance is applied to the sewing needle, and as a result, the state of the seam may be deteriorated. In particular, such a bad seam is not preferable because it affects the appearance.

Therefore, the sewing machines described in Patent Documents 1 and 2 are known as sewing machines for sewing while drawing such a curve. The sewing machines described in Patent Documents 1 and 2 both force the needle bar to mechanically rotate by a gear mechanism such as a rack or pinion, thereby changing the direction of the upper thread passed through the needle hole. I am trying to let you.

Japanese Patent Publication No. 3-19797 JP-A-4-26434

However, each of these sewing machines requires a complicated gear mechanism for achieving both the vertical reciprocation of the needle bar and its own axis rotation, which increases the manufacturing cost of the sewing machine, and if it is not made very well, There was a problem that the operation of became unstable. In particular, in a sewing machine used for industrial use, in addition to an increase in manufacturing cost, unstable operation leads to a decrease in product yield, which is a serious problem.

The present invention has been made in view of the above-described problems, and provides a sewing machine and a needle bar that can be finished with a simple structure and a beautiful seam when a workpiece is sewn while drawing a curve. Objective.

In order to achieve the above object, the present invention comprises a sewing machine body, a needle bar provided on the sewing machine body, and a sewing needle held by the needle bar, and the needle bar and the sewing needle are attached to the sewing machine body. In a sewing machine that reciprocates up and down, the needle bar rotates about its own axis around the axis of reciprocating movement. According to this, since the needle bar holding the sewing needle rotates about its own axis in the vertical reciprocating motion, the resistance of the upper thread to the sewing needle can be reduced, so that the seam can be finished finely. .

The needle bar is divided into a distal needle bar that holds a sewing needle on the axis of vertical reciprocation and a proximal needle bar provided on a coaxial sewing machine body, and the distal needle It is preferable that the bar rotates about the axis of the reciprocating motion with respect to the proximal needle bar. According to this, since the tip side needle bar rotates about the axis of the vertical reciprocation with respect to the base side needle bar, only the needle bar needs to be replaced without changing the conventional vertical reciprocation mechanism. The self-axis rotation of the needle bar can be easily realized.

In the needle bar, the proximal needle bar and the distal needle bar are preferably connected to each other via a connecting member so as to be rotatable. According to this, the front end side needle bar can be easily and reliably rotated with respect to the base end side needle bar.

In addition, the needle bar further includes an air injection part for injecting air at a position near the needle bar, and the needle bar is provided with an air receiving part protruding outward in the radial direction of the needle bar on the peripheral side surface. However, it is preferable that the self-rotating shaft rotates about the axis of the reciprocating motion in the vertical direction by receiving the air ejected by the air ejecting unit. According to this, the needle bar can be rotated in its own axis at a predetermined timing by the air injection by the air injection unit.

In addition, the air injection unit includes a right air injection unit arranged on the right side of the air receiving part of the needle bar and a left air injection unit arranged on the left side of the air receiving part of the needle bar, By injecting air from the air injection unit to the right side surface of the air receiving unit of the needle bar, the needle bar rotates in the left direction about the axis of the reciprocating motion, while the needle from the left air injection unit It is preferable that the needle bar is rotated in the right direction around the axis of the up-and-down reciprocating motion by injecting air to the left side surface of the air receiving portion of the bar. According to this, the needle bar can be accurately rotated at a predetermined timing by the jet of air by the left and right air jet sections.

Moreover, it is preferable that a plurality of the air injection units are provided in a state of being arranged in the vertical direction. According to this, the air receiving part can receive the air injected from the air injection part reliably.

Further, it is preferable that the air receiving portion is provided with a recess for receiving the air injected by the air injection portion on the right side surface and / or the left side surface. According to this, since the air injected from the air injection part flows into the recessed part of the air receiving part, the air receiving part can receive air more efficiently. *

The needle bar further includes a guide part for guiding the needle bar at a position in the vicinity of the needle bar, and the needle bar is provided with a protruding part projecting radially outward of the needle bar on a peripheral side surface. In the ascending and / or descending movement, the protrusion may be rotated about the axis of the vertical reciprocating movement as the protrusion is guided by the guide. According to this, the needle bar can be reliably rotated around the axis of the reciprocating motion according to the guidance of the protruding portion by the guide portion.
The needle bar gradually rotates around its axis in the vertical reciprocation as the protrusion is guided by the guide during the downward movement of the needle bar, and has a predetermined basic posture at the bottom dead center. It is preferable to return to. According to this, when the needle bar returns to the predetermined basic posture at the bottom dead center of the reciprocating motion, the needle hole of the sewing needle is directed in a predetermined direction inside the hook, and the upper thread passing through the needle hole and the hook The inner bobbin thread can be reliably engaged.

A needle bar according to the present invention is a needle bar used in the above-described sewing machine, and includes a distal-side needle bar that holds a sewing needle on the axis of vertical reciprocating motion, and a proximal-side needle provided on the sewing machine body on the coaxial line. The tip side needle bar is configured to rotate about the axis of the reciprocating motion up and down with respect to the base side needle bar.

According to the present invention, since the needle bar holding the sewing needle rotates about its own axis in the vertical reciprocating motion, the resistance of the upper thread to the sewing needle can be reduced, so that the seam can be finished beautifully. it can. In addition, since a complicated self-rotating mechanism that is linked to the vertical reciprocating motion of a conventional sewing machine is not required, the construction cost can be reduced and the needle bar can be stably reciprocated vertically. It is possible to exercise and thus improve the product yield.

1 is an overall configuration diagram of a sewing machine according to a first embodiment of the present invention. FIG. 2 is a front view of the vicinity of a needle bar of the sewing machine of FIG. 1. It is a disassembled perspective view of the needle bar of the sewing machine of FIG. It is sectional drawing of the needle bar of the sewing machine of FIG. It is a whole block diagram of the sewing machine which concerns on the 2nd Embodiment of this invention. FIG. 6 is a front view of the vicinity of the needle bar of the sewing machine of FIG. 5. FIG. 6 is a rear view of the vicinity of the needle bar of the sewing machine of FIG. 5. FIG. 6 is a right side view of the vicinity of the needle bar of the sewing machine of FIG. 5. FIG. 6 is a plan view of the vicinity of the needle bar of the sewing machine of FIG. 5. In the sewing machine of FIG. 5, (a) in the basic posture, (b) when rotated to the left, (c) a plan view of the vicinity of the needle bar when rotated to the right (left) and a cross-sectional view of the sewing needle (Right figure). It is a right view of the vicinity of the needle bar of the sewing machine according to the third embodiment of the present invention. FIG. 12 is a right side view (upper view) of the vicinity of the needle bar when the sewing machine of FIG. 11 moves downward and a cross-sectional view (lower view) of the sewing needle. FIG. 12 is a right side view (upper view) of the vicinity of the needle bar when the sewing machine of FIG. 11 moves upward, and a cross-sectional view (lower view) of the sewing needle.

Next, an embodiment according to the present invention will be described with reference to the drawings.
In each embodiment, the length direction of the sewing machine (the left-right direction in FIGS. 1 and 5) is the front-rear direction, the direction orthogonal to the length direction of the sewing machine on the plane (the direction to sew the workpiece) is the left-right direction, The axial direction of the needle bar of the sewing machine is the vertical direction. Also, when viewed from the front of the sewing machine, the front side is the front side, the right side (front side in FIG. 1) is the “right side”, and the left side (back side in FIG. 1) is the “left side”.
<First Embodiment>
First, a first embodiment of a sewing machine 1 according to the present invention will be described with reference to FIGS.

As shown in FIGS. 1 and 2, the sewing machine 1 includes a sewing machine body 10 that accommodates each part, a needle bar 20 provided on the sewing machine body 10, a sewing needle 30 held on the needle bar 20, and a sewing needle. 30, a holding plate 50 that holds the cloth, and a feed mechanism 60 that feeds the cloth. The needle bar 20 and the sewing needle 30 are reciprocated up and down by a drive motor (not shown). . The needle bar 20 and the needle are reciprocated up and down with respect to the shuttle 40 while manually or automatically feeding workpieces such as synthetic leather, leather, and cloth by the feed mechanism 60, and are passed through the sewing needle 30. The upper thread t and the lower thread (not shown) passed through the hook 40 are sewn on the workpiece.

The needle bar 20 is connected to a drive motor (not shown) via a rotation transmission mechanism 11 so that the rotational drive by the drive motor is converted into a vertical reciprocating motion through the rotation transmission mechanism 11. As shown in FIG. 1, the rotation transmission mechanism 11 includes a transmission belt 111 connected to a drive motor, a pulley 112 around which the transmission belt 111 is wound and provided on a side surface of the sewing machine body 10, and the pulley. An upper shaft 113 extending in the length direction from 112 to the inside of the sewing machine body 10, a link member 114 provided at the distal end portion of the upper shaft 113, and an arm member 115 provided at the distal end portion of the link member 114 The arm member 115 is connected to the needle bar 20.

Thus, when a drive motor (not shown) rotates, the pulley 112 rotates through the conductive belt 111, and the upper shaft 113 rotates in the sewing machine body 10 along with the rotation. As the upper shaft 113 rotates, the link member 114 rotates about the upper shaft, and the rotation of the link member 114 is converted into a vertical reciprocating motion of the arm member 115, so that the arm member 115 moves up and down. Along with the reciprocating motion, the needle bar 20 and the sewing needle 30 also reciprocate up and down.

Further, the needle bar 20 is divided into two on the axis G of the up-and-down reciprocating motion, that is, a distal needle bar 21 and a proximal needle bar 22, and the distal needle bar 21 becomes a proximal needle bar 22. It is connected so that it can rotate. More specifically, as shown in FIGS. 3 and 4, the needle bar 20 includes a thin short cylindrical tip side needle bar 21 that holds the sewing needle 30 on the axis G of the reciprocating motion, and a coaxial line. A thin long cylindrical base end side needle bar 22 connected to the rotation transmission mechanism 11 in the sewing machine body 10 on the G, a head part 23a connecting the front end side needle bar 21 and the base end side needle bar 22 and the body It is comprised from the connection member 23 which consists of a part 23b.

The proximal end side needle bar 22 is opened with a large diameter so that the upper end opening 22a can be inserted into the head 23a and the body 23b of the connecting member 23, and the lower end opening 22b is the body of the connecting member 23. It is opened with a small diameter so that only 23b can be inserted. Further, the tip side needle bar 21 is provided with a recess 21a for fitting the body portion 23b of the connecting member 23 at the upper end portion, and a holding hole 21b for holding the needle at the lower end portion.

When assembling the needle bar 20, when the connecting member 23 is inserted in the direction of the axis G from the upper end opening 22 a of the long cylindrical base end side needle bar 22, the connection is made at the lower end opening 22 b of the base end side needle bar 22. The body portion 23b of the member 23 penetrates and protrudes, and the head portion 23a of the connecting member 23 is locked. Then, after the recess 21a of the short cylindrical needle bar 21 is fitted into the body 23b of the connecting member 23 protruding from the lower end opening 22b of the proximal needle bar 22, the fixing member 24 such as a pin is inserted. Thus, the connecting member 23 and the distal needle bar 21 are fixed. Thus, the connecting member 23 is rotatable about the axis G of the up-and-down reciprocating motion with respect to the proximal end needle bar 22, while being fixed to the distal end needle bar 21. The distal needle bar 21 can rotate about the axis G of the vertical reciprocating motion with respect to the proximal needle bar 20 via the connecting member 23.

Thus, when a workpiece such as an air bag or a seat of an automobile is sewn while drawing a curve, the direction of sewing and the direction of the thread are different in the sewing process, so that the needle hole 30a of the sewing needle 30 is passed through. The upper thread t thus made contacts with the sewing needle 30 and gives resistance, but the distal end side needle bar 21 holding the sewing needle 30 moves up and down in a direction that eliminates the resistance with respect to the proximal side needle bar 22. Therefore, the resistance of the upper thread t to the sewing needle 30 can be reduced, and the seam can be finished finely. In addition, since the tip side needle bar 21 rotates on its own axis, it does not require a complicated self-axis rotating mechanism that is linked to the vertical reciprocating motion such as a conventional sewing machine. 20 can stably reciprocate up and down.

<Second Embodiment>
Next, a second embodiment of the sewing machine according to the present invention will be described with reference to FIGS.

In the following, only the configuration different from the above embodiment will be described, and the description of the same configuration will be omitted and the same reference numeral will be given. Further, the position at which the needle bar 20 is most raised in the vertical reciprocation of the needle bar 20 of the sewing machine is referred to as top dead center, and the position at which the needle bar 20 is lowest is referred to as bottom dead center.

In the present embodiment, as shown in FIGS. 5 to 8, an air injection unit 70 is provided at a position near the rear of the needle bar 20, and an air receiving unit is provided on the rear peripheral side surface of the needle bar 21 at the tip side. 25, and the air receiving portion 25 receives the air jetted by the air jetting portion 70, so that the distal end side needle bar 21 is rotated around the axis G of the vertical reciprocating motion with respect to the proximal side needle bar 22. The axis rotates.

As shown in FIGS. 5 and 8, the air receiving portion 25 is a rectangular plate-like member provided in a manner protruding from the rear peripheral side surface of the distal end side needle bar 21 to the rear of the sewing machine (rightward in FIG. 8). And is fixed to the distal needle bar 21 via a clamp member 27.

As shown in FIGS. 5 and 9, the air receiving portion 25 is formed so as to extend in the front-rear direction and the up-down direction, and the air injected from the air injection portion 70 on the right side surface 251 and the left side surface 252 thereof. To receive. In the present embodiment, circular recesses 25 a are provided on the right side surface 251 and the left side surface 252 of the air receiving portion 25. Thereby, since the air injected from the air injection part 70 flows into the recessed part 25a of the air receiving part 25, the air receiving part 25 can receive air more efficiently. *

Note that, as shown in FIGS. 9 and 10A, the basic posture of the needle bar 20 is that the air receiving portion 25 is parallel to the length direction of the sewing machine (the right direction in FIG. 5).

As shown in FIGS. 6 to 9, the air injection unit 70 includes a pair of upper and lower right

air injection units

71 and 71 disposed on the right side of the air receiving unit 25 of the tip side needle bar 21, and the tip side needle bar 21. And a pair of upper and lower left

air injection portions

72, 72 disposed on the left side of the air receiving portion 25, and are disposed symmetrically behind the needle bar 20.

These right

air injection parts

71 and 71 and left

air injection parts

72 and 72 all have an air injection port 70a for injecting air inward in the horizontal direction. For this reason, when air is injected from the right

air injection portions

71 and 71 to the right side 251 of the air receiving portion 25 of the needle bar 20 in the basic posture shown in the left drawing of FIG. 10A, the left drawing of FIG. As shown in FIG. 2, the distal end side needle bar 21 rotates on its own axis in the left direction around the axis of the reciprocating motion. On the other hand, when air is injected from the left

air injection parts

72, 72 to the left side 252 of the air receiving part 25 of the needle bar 20 in the basic posture shown in the left figure of FIG. 10A, the left figure of FIG. As shown, the distal end side needle bar 21 rotates in the right direction around the axis of the reciprocating motion.

Since the right

air injection portions

71 and 71 and the left

air injection portions

72 and 72 are all arranged in parallel in the vertical direction, the needle bar 20 is moved upward as shown in FIGS. When the dead center is reached, the air receiving portion 25 can reliably receive the air injected from the right

air injection portions

71 and 71 or the left

air injection portions

72 and 72.

Thus, when the needle bar 20 reaches the top dead center as shown in FIGS. 6 and 7, air is sent from the air pump mechanism to the air injection unit 70 under a command from a control device (not shown). When air is injected from the air injection port 70a of the right

air injection unit

71, 71 or the left

air injection unit

72, 72 at the timing of The rod 21 rotates in its own axis in a predetermined direction around the axis of the reciprocating motion.
The operations of the needle bar 20 and the sewing needle 30 will be specifically described. As shown in the left side of FIG. The basic posture is parallel to the direction. At this time, the upper thread outlet 30a of the needle hole 31 of the sewing needle 30 faces the front of the sewing machine 1, as shown in the right figure of FIG.

Here, when the workpiece is moved while drawing a curve in the right direction (the direction of the thick arrow in FIG. 10B), the needle bar 20 reaches the top dead center as shown in FIGS. When air is injected from the right

air injection parts

71 and 71 to the right side 251 of the air receiving part 25 of the needle bar 20 in the basic posture shown in the left figure of FIG. 10 (a) before and after, the left figure of FIG. 10 (b). As shown in FIG. 4, the distal needle bar 21 rotates about 40 degrees in the left direction around the axis G of the reciprocating motion. At this time, the sewing needle 30 also rotates about 40 degrees in the left direction according to the rotation of the tip side needle bar 21 in the left direction. Therefore, as shown in the right figure of FIG. The upper thread outlet 30a of the hole 31 faces the front right side.

On the other hand, when the workpiece is moved while drawing a curve in the left direction (the direction of the thick arrow in FIG. 10C), before and after the needle bar 20 reaches the top dead center as shown in FIGS. Furthermore, when air is injected from the right

air injection portions

72, 72 to the left side 252 of the air receiving portion 25 of the needle bar 20 in the basic posture shown in the left drawing of FIG. 10A, the left drawing of FIG. As shown, the distal end side needle bar 21 rotates about 40 degrees in the right direction around the axis G of the vertical reciprocating motion. At this time, the sewing needle 30 also rotates about 40 degrees in the right direction according to the rotation of the tip side needle bar 21 in the right direction. Therefore, as shown in the right figure of FIG. The upper thread outlet 30a of the hole 31 faces the front left side.

In addition, when it is desired to return the tip side needle bar 21 rotated in the right direction or the left direction to the basic posture, the right side air injection unit 71 or the left side air injection disposed on the opposite side to the direction in which the basic posture is to be returned. If air is jetted from the portion 72 to the air receiving portion 25 of the needle bar 20, the tip side needle bar 21 can rotate in its own direction in the direction of returning to the basic posture and return to the basic posture.

Thus, the tip side needle bar 21 is rotated at a predetermined timing by the air injection by the air injection unit 70, and the direction of the upper thread outlet 31a of the needle hole 31 of the sewing needle 30 is appropriately changed to the optimum direction. Thus, the resistance of the upper thread t to the sewing needle 30 can be reduced, so that the seam of the workpiece can be finished even more beautifully.

In the present embodiment, the tip side needle bar 21 rotates in its own axis within a range of 40 degrees to the left and right from the basic posture, but may rotate in its own axis within a range of other angles. However, in order to continuously and stably rotate the self-axis of the distal needle bar 21, the self-axis is preferably within a range of 90 degrees or less from the basic posture to the left and right, and more preferably within the range of 45 degrees or less from the basic posture to the left and right. It is good to rotate.

<Third Embodiment>
Next, a third embodiment of the sewing machine according to the present invention will be described with reference to FIGS. In the following, only the configuration different from the above embodiment will be described, and the description of the same configuration will be omitted and the same reference numeral will be given.

In the present embodiment, as shown in FIG. 11, a guide portion 80 is provided in the vicinity of the right side of the needle bar 20, and a protrusion 26 is provided on the right peripheral side surface of the needle bar 21 on the distal end side. When the needle bar 20 moves downward, the protrusion 26 is guided by the guide part 80, whereby the tip side needle bar 21 gradually rotates around the axis G of the vertical reciprocating motion. The robot returns to a predetermined basic posture at the dead center.

As shown in FIG. 11, the protruding portion 26 is a columnar member provided in such a manner that it protrudes from the right peripheral side surface of the distal needle bar 21 in the right direction of the sewing machine (front side in FIG. 11).

The guide portion 80 has a guide groove 80a extending in the vertical direction of the upper opening, as shown in FIG. The guide groove 80a is provided below the first guide groove 81 and the wide first guide groove 81 for guiding the protrusion 26 in different directions, and maintains the protrusion 26 in the same direction. And a narrow guide groove 82 for guiding while guiding.

The first guide groove 81 is formed symmetrically so that the groove width narrows in such a manner that the groove edges 81a on both sides approach each other as it goes from above to below. As a result, when the needle bar 20 moves downward from the top dead center, the protruding portion 26 slides on the groove edge 81a of the first guide groove 81 and faces in the left or right direction along the shape of the groove edge 81a. While being guided down.

The second guide groove 82 is formed with a narrow and constant groove width so as to extend downward from the first guide groove 81. The first guide groove 82 is formed to have a groove width slightly larger than the diameter of the protruding portion 26. As a result, when the needle bar 20 further moves downward, the protruding portion 26 guided through the first guide groove 81 is guided downward along the second guide groove 82 in the same direction.

The operation of the needle bar 20 and the sewing needle 30 will be described in detail. When the workpiece is moved while drawing a curve in the right direction, the tip side needle bar 21 is at the top dead center and the right air injection unit 72. By receiving the air jetted from the air receiving portion 25, as shown in the upper part of FIG. 12A, it is in a state of rotating about its own axis in the left direction around the axis G of the vertical reciprocating motion. At this time, since the sewing needle 30 is rotating in the left direction in accordance with the rotation in the left direction of the tip side needle bar 21, the needle hole 31 of the sewing needle 30 is shown in the lower view of FIG. The upper thread outlet 30a faces the front right side.
Next, when the needle bar 20 moves downward from the top dead center, the protrusion 26 slides on the groove edge 81a on the rear side of the first guide groove 81, as shown in the upper view of FIG. It is guided downward while gradually turning rightward along the shape of the rear groove edge 81a. For this reason, the tip side needle bar 21 also rotates its own axis in the direction returning to the basic posture (in this description, the right direction around the axis G of the vertical reciprocating motion) and gradually returns to the basic posture. At this time, the sewing needle 30 also rotates in the right direction in accordance with the rotation of the distal end side needle bar 21 in the right direction. Therefore, as shown in the lower diagram of FIG. Go to the front.
Next, when the needle bar 20 further moves down to the bottom dead center, the protrusion 26 that has guided the first guide groove 81 into the second guide groove 82 as shown in the upper part of FIG. Along the same direction, it is guided downward. For this reason, the tip side needle bar 21 moves to the bottom dead center while maintaining the basic posture. At this time, the sewing needle 30 also maintains its state in accordance with the maintenance of the basic posture of the distal end side needle bar 21, so that the upper thread outlet 30a of the needle hole 31 faces the front as shown in the lower diagram of FIG. To maintain.
Thus, the needle thread 30a of the needle 30a of the sewing needle 30 is directed to the front inside the hook 40 by returning the tip side needle bar 20 to the predetermined basic position at the bottom dead center of the vertical reciprocation. The upper thread passing through the needle hole 30 and the lower thread inside the hook 40 can be reliably engaged.
On the other hand, when the needle bar 20 moves upward from the bottom dead center, as shown in the upper diagrams of FIGS. 13 (a) and 13 (b), the protruding portion 26 remains in the same direction along the second guide groove 82 to the top dead center. You will be guided. Therefore, the distal needle bar 21 moves to the top dead center while maintaining the basic posture. The sewing needle 30 also maintains its state according to the maintenance of the basic posture of the distal needle bar 21, so that the upper thread outlet 30a of the needle hole 31 faces the front as shown in the lower views of FIGS. 13 (a) and 13 (b). Maintain the condition.
Next, the tip side needle bar 21 receives the air jetted from the right air jet part 72 at the top dead center again by the air receiving part 25, and as shown in FIG. It is in a state of rotating around its own axis G in the left direction. At this time, the sewing needle 30 rotates in the left direction in accordance with the rotation of the tip side needle bar 21 in the left direction, and therefore, as shown in the lower diagram of FIG. The yarn outlet 30a faces the front right side.

Thereafter, the above-described operations of the needle bar 20 and the sewing needle 30 are repeated according to the vertical reciprocation of the needle bar 20.
When the workpiece is moved while drawing a curve in the left direction, the tip side needle bar 21 is reciprocated up and down by receiving the air injected from the left air injection unit 71 at the top dead center by the air receiving unit 25. It is in a state where its own axis rotates in the right direction around the movement axis G. For this reason, when the needle bar 20 moves downward from the top dead center, the protruding portion 26 slides on the groove edge 81a on the front side of the first guide groove 81 and moves to the left along the shape of the groove edge 81a. You will be guided down. For this reason, the distal needle bar 21 also rotates in its own axis in the direction returning to the basic posture (in this description, the left direction around the axis G of the vertical reciprocating motion) and returns to the basic posture. At this time, the sewing needle 30 also rotates in the left direction in accordance with the rotation in the left direction of the tip side needle bar 21, so that the upper thread outlet 30a of the needle hole 31 gradually turns to the front side, and the subsequent operation Is the same as described above.

In the above embodiment, the needle bar 20 is configured to be divided into the proximal end side needle bar 22 and the distal end side needle bar 21, but the needle bar 20 may be configured to be integrated without being divided. .

Further, although the needle bar 20 receives air from the air injection unit 70 before and after the top dead center of the vertical reciprocating motion, the needle bar 20 may receive air from the air injection unit 70 during the upward movement or the downward movement.

Further, although the air receiving portion 25 is formed in a rectangular plate shape, it may be formed in other shapes. Moreover, although the recessed part 25a was provided in the right side 251 and the left side 252 of the air receiving part 25, you may form the right side 251 and the left side 252 flat without providing the recessed part 25a.

Moreover, although the right-side air injection part 71 and the left-side air injection part 72 are provided two at the top and the bottom, only one may be provided, or three or more may be provided.

Further, the guide portion 80 is not limited to the above-described shape, and may have any shape as long as it can guide the protruding portion 26.

The guide 80 guides the protrusion 26 only when the needle bar 20 moves downward, but guides the protrusion 26 when the needle bar 20 moves upward, and follows the guidance of the protrusion 26 by the guide 80. The needle bar (or the tip side needle bar) may be rotated about its own axis around the vertical reciprocating motion.

The embodiments of the present invention have been described above with reference to the drawings. However, the present invention is not limited to the illustrated embodiments. Various modifications and variations can be made to the illustrated embodiment within the same range or equivalent range as the present invention.

Claims

In a sewing machine comprising a sewing machine body, a needle bar provided on the sewing machine body, and a sewing needle held by the needle bar, the needle bar and the sewing needle move up and down relative to the sewing machine body. A sewing machine that rotates on its own axis around an axis of reciprocating motion.
The needle bar is divided into a distal needle bar that holds a sewing needle on the axis of reciprocating motion and a proximal needle bar that is provided on a coaxial sewing machine body, and the distal needle bar is The sewing machine according to claim 1, wherein the sewing machine rotates about its own axis about a vertical reciprocating motion with respect to the proximal needle bar.
3. The sewing machine according to claim 2, wherein the needle bar is configured such that the proximal needle bar and the distal needle bar are rotatably connected to each other via a connecting member.
An air injection part for injecting air at a position near the needle bar;
The needle bar is provided with an air receiving part protruding outward in the radial direction of the needle bar on a peripheral side surface, and the air receiving part receives air jetted by the air jetting part, so that The sewing machine according to claim 2, wherein the sewing machine rotates on its own axis.
The air injection part is composed of a right air injection part arranged on the right side of the air receiving part of the needle bar and a left air injection part arranged on the left side of the air receiving part of the needle bar. The needle bar is rotated in the left direction around the axis of the reciprocating motion of the needle bar by injecting air from the portion to the right side surface of the air receiving portion of the needle bar. The sewing machine according to claim 4, wherein the needle bar is rotated in the right direction about an axis of reciprocating motion by jetting air toward the left side surface of the air receiving portion.
The sewing machine according to claim 4, wherein a plurality of the air injection units are arranged in a vertical direction.
The sewing machine according to claim 4, wherein the air receiving portion is provided with a recess for receiving air injected by the air injection portion on the right side surface and / or the left side surface.
A guide portion for guiding the needle bar at a position near the needle bar;
The needle bar is provided with a projecting portion that protrudes radially outward of the needle bar on the peripheral side surface, and moves upward and downward as the projecting portion is guided by the guide portion during the upward and / or downward movement of the needle bar. The sewing machine according to any one of claims 1 to 7, wherein the sewing machine rotates on its own axis around an axis of reciprocation.
The needle bar gradually rotates around its axis in the vertical reciprocating motion as the protrusion is guided by the guide during the downward movement of the needle bar, and returns to a predetermined basic posture at the bottom dead center. The sewing machine according to claim 8.
A needle bar used for a sewing machine, which is configured by being divided into a tip side needle bar that holds a sewing needle on the axis of vertical reciprocation and a base side needle bar that is provided on a coaxial sewing machine body, A needle bar characterized in that the tip side needle bar rotates about its own axis in the vertical reciprocating motion with respect to the base side needle bar.