TW201445018A - Sewing machine and needle bar - Google Patents

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 in sewing a workpiece such as a synthetic leather, a leather product, or a cloth, and a needle bar for use in the sewing machine. Mainly used for industrial purposes.

The general sewing machine is composed of a sewing machine body, a needle bar located on the machine body of the sewing machine, a needle fixed to the needle bar, a kettle for receiving the needle, and a feeding device for feeding. The needle bar and the needle are reciprocated up and down under the action of the drive motor. Then, the feeding mechanism feeds the processed leather, the leather product, the cloth and the like by manual or automatic feeding, and the needle bar and the needle reciprocate up and down with respect to the kettle, so that the upper thread passing through the needle and the lower thread passing through the kettle are paired The workpiece is sewn.

Recently, the sewing machine has also realized the function of sewing a special object such as a car airbag and a car seat, but the sewing direction of these special-purpose workpieces is mostly a circular curve rather than a straight line.

When sewing in the direction of the curve, the sewing direction is inconsistent with the direction of the thread during the sewing process, so the upper thread passing through the needle hole will come into contact with the needle, causing unnecessary resistance to the needle, eventually resulting in the needle. The situation is uneven. In particular, when the stitches are very irregular, the appearance of the workpiece is affected, making it very unattractive.

The sewing machine described in Patent Documents 1 and 2. It is known for its ability to sew along the direction of the curve. The sewing machines described in Patent Documents 1 and 2 are each constituted by a gear device such as a rack and a pinion. The needle bar is mechanically forcedly rotated by the gear device and changes the direction of the upper thread passing through the pinhole.

[Previous Technical Literature]

[Patent Literature]

[Patent Document 1] Special Fair 3-19797

[Patent Document 2] Japanese Patent Publication No. 4-26434

However, since this type of sewing machine has both the up and down reciprocating motion and the self-axis rotational motion of the needle bar, a relatively complicated gear device structure is required. This will not only increase the manufacturing cost of the sewing machine, but if the gear structure is not made precise enough, there will be a problem that the needle bar is unstable. In particular, for a sewing machine for industrial use, the increase in manufacturing cost is inevitably increased, and the low yield of the product caused by the instability of the needle bar operation is also a major problem.

In view of the above problems, the present invention has established the object of providing a sewing machine and a needle bar which are simple in construction so that the stitches can be neat and tidy when the workpiece is sewn in the direction of the curve.

In order to achieve the above object, the present invention mainly has the following features. The sewing machine includes a sewing machine body, a needle bar on the body of the sewing machine, and a needle fixed to the needle bar. A sewing machine for a needle bar and a needle that reciprocates up and down with respect to a sewing machine body, the needle bar performs a self-axis rotation motion around an axis that reciprocates up and down. In this way, by performing the self-axis rotation movement around the axis of the reciprocating motion of the needle bar of the fixed needle, the resistance of the upper thread to the needle can be alleviated, thereby making the stitching neat and beautiful.

In addition, the aforementioned needle bar is composed of two major parts. One is to fix the needle to the distal end side needle bar on the axis for reciprocating up and down, and the other is to provide the proximal end side needle bar of the sewing machine body on the coaxial line. It is preferable that the distal end side needle bar is capable of performing a self-axis rotational motion around an axis that reciprocates up and down with respect to the proximal end side needle bar. In this manner, since the distal end side needle bar is pivotally moved around the axis of the vertical reciprocating movement with respect to the needle bar at the holding arm, it is possible to change the structure of the conventional vertical reciprocating motion without changing the conventional structure. The needle bar can easily perform the free rotation of the needle bar.

Further, in the needle bar, it is preferable that the base end side needle bar and the distal end side needle bar are rotatably connected to each other by a connecting member. In this way, the front end side needle bar can simply and surely allow the base end side needle bar to freely rotate.

Further, in the vicinity of the needle bar, an air ejecting portion that can eject air is provided. its In the above-mentioned needle bar, the air receiving portion is provided on the outer side surface of the needle bar, that is, the outer side in the diameter direction of the needle bar, and the air receiving portion receives the air ejected from the air ejecting portion to surround the needle bar about the axis that reciprocates up and down. Perform a self-axis rotation motion. Thus, the needle bar can perform the self-axis rotational motion at a predetermined timing by the air ejected from the air ejecting portion.

Further, the aforementioned air ejection portion is composed of two parts. Each of the right side air ejecting portion located on the right side of the air receiving portion of the needle bar and the left side air ejecting portion located on the left side of the air receiving portion of the needle bar. Air is ejected toward the right side of the air receiving portion of the needle bar by the right air ejecting portion, so that the needle bar rotates to the left around the axis of the vertical reciprocating motion, and the left air ejecting portion faces the aforementioned The left side of the air receiving portion of the needle bar ejects air so that the needle bar can perform a self-axis rotational motion to the right around the axis of the upper and lower reciprocating motion. In this manner, the needle bar can be freely rotated at a predetermined timing by the discharge of the air from the left and right air ejection portions.

Further, since the plurality of air injection mechanisms arranged side by side are provided in the vertical direction, the air receiving portion can surely receive the air ejected from the air ejecting portion.

Further, in order to receive the air ejected from the air ejecting portion, it is preferable to provide a concave surface on the right side and/or the left side of the air receiving portion. In this way, since the air ejected through the air ejecting portion flows to the concave surface of the air receiving portion, the air receiving portion can receive the air more efficiently.

Further, in the vicinity of the needle bar, a guide portion for guiding the movement of the needle bar is further provided. The aforementioned needle bar is provided with a protruding portion that protrudes outward on the side surface thereof, that is, the outer side in the diameter direction of the needle bar. When the needle bar is raised and/or lowered, the needle bar performs a self-axis rotational motion about the axis of the upper and lower reciprocating motion as the protruding portion is guided by the guiding portion. In this manner, as the protruding portion is guided by the guiding portion, the needle bar can be surely rotated around the axis that reciprocates up and down.

Further, when the needle bar is subjected to the descending motion, the self-axis rotational motion is continuously performed around the axis of the reciprocating motion by the guidance of the protruding portion of the guiding portion, and the predetermined position is restored at the bottom dead center. The basic orientation is better. In this way, since the needle bar recovers its predetermined basic orientation at the bottom dead center of the upper and lower reciprocating motion, the pinhole of the needle is oriented in a specified direction inside the sewing machine, so that the upper thread passing through the pinhole can be surely The lower thread inside the sewing machine is engaged.

The needle bar associated with the present invention is a needle bar for the above sewing machine, which is composed of two major parts. One is to fix the needle to the front end side needle bar on the axis for reciprocating up and down, and the other is to provide the base end side needle bar of the sewing machine body on the coaxial line. Wherein the front end side needle bar is opposite to the base The end side needle bar performs a self-axis rotation motion around an axis that reciprocates up and down.

By utilizing the present invention, by performing the self-axis rotation movement around the axis of the upper and lower reciprocating needles of the fixed needle, the resistance of the upper thread to the needle can be alleviated, thereby making the stitches neat and beautiful. Further, since the structure of the present invention is relatively simple, there is no need for a conventional self-rotating structure in which the sewing machine has a complicated reciprocating motion and interlocking, so that the production cost can be controlled. At the same time, because it enables the needle bar to stably reciprocate up and down, thereby improving the yield of the product.

1‧‧‧ sewing machine

10‧‧‧Sewing machine body

11‧‧‧Rotary transmission

20‧‧‧ Needle bar

21‧‧‧ front end needle bar

22‧‧‧Based side needle bar

25‧‧‧Air Receiving Department

25a‧‧‧ concave

26‧‧‧Protruding

27‧‧‧ fasteners

30‧‧‧ pinhole (line exit)

30a‧‧‧needle

31‧‧‧ pinhole

40‧‧‧ kettle

50‧‧‧ Pressing board

70‧‧‧Air Ejection Department

70a‧‧ Air jet

71‧‧‧Right air ejector

72‧‧‧left air venting section

80‧‧‧Guidance Department

81‧‧‧1st guiding slot

81a‧‧‧ slot edge

82‧‧‧2nd guiding slot

111‧‧‧Drive belt

112‧‧‧Drive wheel

113‧‧‧Upper axis

114‧‧‧Connecting parts

115‧‧‧ rocker parts

251‧‧‧ right side

252‧‧‧ left side

t‧‧‧Online

[Fig. 1] Fig. 1 is an overall structural view of a sewing machine according to a first embodiment of the present invention.

[Fig. 2] is a front view of the periphery of the needle bar of the sewing machine shown in Fig. 1.

[Fig. 3] is an exploded perspective view of the needle bar of the sewing machine shown in Fig. 1.

Fig. 4 is a cross-sectional view showing the needle bar of the sewing machine shown in Fig. 1.

[Fig. 5] Fig. 5 is an overall structural view of a sewing machine according to a second embodiment of the present invention.

[Fig. 6] is a front view of the needle bar around the sewing machine shown in Fig. 5.

[Fig. 7] is a rear view around the needle bar of the sewing machine shown in Fig. 5.

[Fig. 8] is a right side view of the needle bar of the sewing machine shown in Fig. 5.

[Fig. 9] is a plan view of the periphery of the needle bar of the sewing machine shown in Fig. 5.

[Fig. 10] is a plan view (left) of the sewing machine, (a) basic orientation, (b) left rotation, and (c) rotation to the right, and a sectional view of the needle (right) Figure).

Fig. 11 is a right side view of the vicinity of a needle bar of a sewing machine according to a third embodiment of the present invention.

[Fig. 12] A right side view (top view) around the needle bar and a sectional view of the needle (bottom view) for the downward movement of the sewing machine of Fig. 11.

[Fig. 13] A right side view (top view) around the needle bar and a sectional view of the needle (bottom view) for the sewing machine of Fig. 11 when moving upward.

Next, an embodiment related to the present invention will be described with reference to the drawings.

Further, in each of the embodiments, the longitudinal direction of the sewing machine (the horizontal direction in the first and fifth figures) is regarded as the front-rear direction, and the longitudinal direction of the sewing machine is in the vertical direction on the plane (the sewing is added) The direction of the workpiece is regarded as the left and right direction, and the axial direction of the needle bar of the sewing machine is regarded as the up and down direction. In addition, the side from which the sewing machine is viewed from the front is regarded as the front side, and the right side of the front side (the front side of the first drawing) is the "right side", and the left side of the front side (the inner side of the first drawing) 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. 1 to 4 .

This sewing machine 1 is composed of the parts shown in Fig. 1 and Fig. 2 . The sewing machine body 10 for accommodating the respective parts, the needle bar 20 provided on the sewing machine body, the needle 30 fixed to the needle bar 20, the kettle 40 for receiving the needle 30, the pressing plate 50 for pressing the cloth, and the feeding device 60 for conveying the cloth . The needle bar 20 and the needle 30 are reciprocated up and down by a drive motor (not shown). Then, by the feeding device 60, the workpieces such as synthetic leather, leather products, and cloth are manually or automatically fed, and the needle bar 20 and the slit are reciprocated up and down with respect to the kettle 40, thus passing through the upper thread t of the needle 30 and The workpiece is sewn through the lower thread (not shown) of the kettle 40.

The needle bar 20 is coupled to the rotation transmission 11 by a drive motor (not shown). Under the action of the drive motor, the rotary drive is converted into an up-and-down reciprocating motion by the rotary transmission 11. As shown in Fig. 1, the rotary transmission 11 has a transmission belt 111 connected to a drive motor, a transmission wheel 112 mounted on a side surface of the sewing machine body 10 with a transmission belt, and a lengthwise direction from the transmission wheel 112 to the inside of the sewing machine body 10. The extended upper shaft 113, the connecting member 114 provided at the front end portion of the upper shaft 113, and the rocker member 115 provided at the front end portion of the connecting member 114. The rocker arm member 115 is coupled to the needle bar 20.

Thus, when the drive motor (not shown) is operated, the drive wheel 112 starts to operate by the belt 111, and the upper shaft 113 also undergoes a self-axis rotational motion in the machine body 10. Next, as the self-axis rotational movement of the upper shaft 113, the connecting member 114 rotates around the upper shaft. The rotation of the connecting member 114 is converted into the up-and-down reciprocation of the rocker member 115, and with the vertical reciprocation of the rocker member 115, the needle bar 20 and the needle 30 also start to reciprocate up and down.

Further, the aforementioned needle bar 20 may be divided into a distal end side needle bar 21 and a proximal end side needle bar 22 located on the upper and lower reciprocating axis G. The distal end side needle bars are coupled to each other with respect to the proximal end side needle bar 22 so as to be rotatable relative to each other. Specifically, as shown in FIG. 3 and FIG. 4, the constituent portion of the needle bar 20 includes a distal end side needle bar 21 which is fixed in a short cylindrical shape on the axis G for reciprocating up and down, and is coaxial. An elongated cylindrical base end needle bar 22 connected to a rotation transmission device in the sewing machine body 10 on the line G, and a coupling member 23 that connects the distal end side needle bar 21 and the proximal end side The head portion 23a of the needle bar 22 and the trunk portion 23b are formed.

The proximal end side needle bar 22 has a large opening diameter of the upper end opening portion 22a, and can be inserted into the head portion 23a and the trunk portion 23b of the connecting member 23. The lower end opening portion 22b is relatively small, and can only be inserted into the trunk portion 23b of the connecting member 23. Further, the upper end of the distal end side needle bar 21 is provided with a concave surface 21a which can be fitted into the trunk portion 23b of the connecting member 23, and a lower end thereof is provided with a holding hole 21b for fixing the sewing needle.

When the needle bar 20 is assembled, when the upper end opening 22a of the long cylindrical proximal end needle bar 22 is inserted in the direction of the axis G toward the connecting member 23, the lower end opening portion 22b of the proximal end side needle bar 22 passes through The trunk portion 23b of the connecting member 23 is protruded, and at the same time, the head portion 23a of the connecting member 23 is in a locked state. Then, the concave portion 21a of the short cylindrical distal end side needle bar 21 is inserted into the trunk portion 23b of the connecting member 23 that protrudes from the lower end opening portion 22b of the proximal end side needle bar 22, and then the fixing pin or the like is fixed. The fixing member 24 fixes the connecting member 23 and the front end side needle bar 21. Then, the connecting member 23 can be rotated about the axis G on which the proximal end side needle bar 22 reciprocates up and down. On the other hand, since the distal end side needle bar 21 is formed in a fixed configuration, the distal end side needle bar 21 can perform a self-axis rotational motion around the axis G for reciprocating up and down by the connecting member 23 with respect to the proximal end side needle bar 20. .

As described above, when the workpiece for special use such as the automobile airbag and the car seat is sewn along the curve, since the direction of the sewing and the direction of the needle thread are not uniform during the sewing process, the pinhole 30a is passed through the needle 30. The upper thread t is in contact with the needle 30 and generates a certain resistance, but since the front end side needle bar 21 of the fixed needle 30 is rotated around the axis G which can reciprocate up and down in the direction of eliminating the resistance of the proximal end side needle bar 22 Therefore, the resistance of the upper thread t to the needle 30 is reduced, so that the stitched stitch is neat and beautiful. Further, when the distal end side needle bar 21 performs the self-rotation of the shaft, there is no need for a complicated self-rotating structure such as the vertical reciprocating motion and the interlocking device as in the conventional sewing machine, and since the structure is simple, the production cost can be controlled. At the same time, it also enables the needle bar to 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. 5 to 10 .

Further, the following description is merely illustrative of the configuration that is different from the above-described embodiment, and the description of the same structure will be omitted and the same reference numerals will be given. Further, regarding the vertical reciprocating motion of the sewing machine needle bar 21, the highest position reached by the needle bar 20 is referred to as the top dead center, and the most reached by the needle bar 20 The low position is called the bottom dead center.

As shown in FIGS. 5 to 8 , in the present embodiment, the air ejecting unit 70 is provided in the vicinity of the rear of the needle bar 20, and the air receiving portion is provided on the side surface of the distal end side needle bar 21 of the needle bar 20 . 25. The air receiving unit 25 receives the air ejected from the air ejecting unit 70, and the distal end side needle bar 21 can perform a self-rotating motion about the axis G that reciprocates up and down with respect to the proximal end side needle bar 22.

As shown in FIGS. 5 to 8 , the air receiving portion 25 is a rectangular member that is provided to protrude from the rear side surface of the distal end side needle bar 21 toward the rear of the sewing machine (the right side of FIG. 8 ). It is fixed to the front end side needle bar 21 by a fastener 27.

As shown in FIGS. 5 and 9, the air receiving portion 25 is formed to extend in the vertical direction and the front-rear direction. The air discharged from the air ejection portion 70 is received at the right side surface 251 and the left side surface 252. Further, in the present embodiment, a circular concave surface 25a is provided at the right side surface 251 and the left side surface 252 of the air receiving portion 25. In this manner, since the air discharged through the air ejecting portion 70 flows to the concave surface 25a of the air receiving portion 25, the air receiving portion 25 can receive the air more efficiently.

Further, as shown in Fig. 9 and Fig. 10(a), the state in which the air receiving portion 25 is parallel to the longitudinal direction of the sewing machine (the right side in Fig. 5) is regarded as the basic orientation of the needle bar 20.

As shown in FIG. 6 to FIG. 9, the air ejection unit 70 is configured such that a pair of upper and lower right side air ejection portions 71 and 71 disposed on the right side of the air receiving portion 25 of the distal end side needle bar 21 are disposed. The pair of left and right air ejection portions 72 and 72 on the left side of the air receiving portion 25 of the distal end side needle bar 21 and the air ejection portion are disposed symmetrically to the left and right of the needle bar 20 .

The right side air ejection portion 71 and the left side air ejection portion 72 are provided with an air ejection port 70a through which air can be ejected. Therefore, when the right air ejecting portion 71 ejects air toward the right side surface 251 of the air receiving portion 25 of the substantially oriented needle bar 20 shown in the left diagram of Fig. 10(a), as shown in Fig. 10(b) As shown in the left figure, the front end side needle bar 21 performs a self-axis rotation motion on the left side around the axis on which the vertical reciprocation is performed. On the other hand, when the left air ejecting portion 72 ejects air toward the left side surface 252 of the air receiving portion 25 of the substantially oriented needle bar 20 shown in the left diagram of Fig. 10 (a), as shown in Fig. 10 ( c) As shown in the left figure, the front end side needle bar 21 performs a self-axis rotation motion on the right side around the axis on which the upper and lower reciprocating motions are performed.

Further, since the right side air ejecting portions 71 and 71 and the left side air ejecting portions 72 and 72 are both arranged in parallel in the vertical direction, as shown in FIGS. 6 and 7, when the needle bar 20 reaches the top dead center The air receiving portion 25 can be surely received by the right air ejecting portions 71, 71. The air is either air ejected by the left air ejecting portions 72, 72.

As described above, as shown in FIGS. 6 and 7, when the needle bar 20 reaches the top dead center, the air pump device transports the air to the air ejection portion 70 under the command of the control device (not shown), at a predetermined level. In the timing, when the air ejection ports 70a of the right air ejection portions 71, 71 or the left air ejection portions 72, 72 discharge air, the air receiving portion 25 of the distal end side needle bar 21 receives air, and the distal end side needle bar 21 reciprocates up and down. The specified direction around the axis of motion is subjected to a self-axis rotational motion.

The working principle of the needle bar 20 and the needle 30 will be specifically described below. As shown in the left diagram of Fig. 10(a), the front end side needle bar 21 is normally in a substantially directional position parallel to the longitudinal direction of the sewing machine body 1. at this time. As shown in the right diagram of Fig. 10(a), the upper thread outlet 30a of the needle hole 31 of the needle 30 faces the front surface of the sewing machine 1.

Here, when the workpiece moves to the right (the direction of the thick arrow in FIG. 10(b)) along the curve, as shown in FIGS. 6 and 7, when the needle 20 reaches the top dead center, When the right air ejecting portion 71 ejects air toward the right side surface 251 of the air receiving portion 25 of the substantially oriented needle bar 20 shown in the left diagram of Fig. 10(a), as shown in the left figure of Fig. 10(b) It is shown that the distal end side needle bar 21 performs a self-axis rotational motion of about 40 degrees on the left side around the axis on which the vertical reciprocation is performed. At this time, since the needle 30 also performs a self-axis rotation motion of about 40 degrees with respect to the left side around the axis G that reciprocates up and down, the pinhole 31 of the needle 30 is as shown in the right diagram of FIG. 10(b). The upper exit 30a will face the right side of the front.

On the other hand, when the workpiece is moved to the left (in the direction of the thick arrow in FIG. 10(c)) along the curve, as shown in FIGS. 6 and 7, before and after the needle 20 reaches the top dead center When the right side air ejecting portions 72, 72 eject air toward the left side surface 252 of the air receiving portion 25 of the substantially oriented needle bar 20 shown in the left diagram of Fig. 10(a), as shown in Fig. 10(c) As shown in the figure on the left, the distal end side needle bar 21 performs a self-axis rotational motion of about 40 degrees on the right side around the axis G that reciprocates up and down. At this time, since the needle 30 also rotates about 40 degrees from the right side of the distal end side needle bar 21, the pinhole of the needle 30 is as shown in the right figure of FIG. 10(c). The upper exit 30a of 31 will face the left side of the front side.

In addition, if the front end side needle bar 21 that performs the self-axis rotation movement to the right or the left side is restored to the original basic orientation position, the right side air ejection portion is required only in the opposite direction to the direction in which the original basic orientation is to be restored. 71 or the left air ejecting portion 72, the air is ejected toward the air receiving portion 25 of the needle bar 20, and the distal end side needle bar 21 starts to perform the self-axis rotational motion in the direction of returning to the original basic orientation and restores the original basic In place.

In this manner, the distal end side needle bar 21 is rotated by the shaft at a predetermined timing by the air ejected from the air ejecting unit 70, and the direction of the upper thread outlet 31a of the pinhole 31 of the needle 30 is turned to the most appropriate direction, and the needle 30 is rotated. The resistance to the upper thread t is reduced, making the stitches of the workpiece more tidy and beautiful.

Further, in the present embodiment, the distal end side needle bar 21 is rotated from the basic orientation to about 40 degrees in the left and right direction. However, it is also possible to perform a self-axis rotation motion in other angle ranges. However, it is to be noted that in order to continuously and stably perform the self-axis rotational movement of the distal end side needle bar 21, it is preferable to be in a range of 90 degrees or less from the basic orientation to the left and right direction. The optimum state is the self-axis rotation motion from the basic orientation to the left-right direction of 45 degrees or less.

<Third embodiment>

Next, a third embodiment of the sewing machine according to the present invention will be described with reference to Figs. 11 to 13 . Further, the following description is merely illustrative of the configuration that is different from the above-described embodiment, and the description of the same structure will be omitted and the same reference numerals will be given.

In the present embodiment, as shown in FIG. 11, the guide portion 80 is provided in the vicinity of the right side of the needle bar 20, and the projecting portion 26 is provided on the side surface of the right-hand side of the distal end side needle bar 21 of the needle bar 20. When the needle bar 20 is moved downward, the front end side needle bar 21 is sequentially rotated from the axis around the axis G for reciprocating up and down by the guiding portion 80, and the bottom dead center of the upper and lower reciprocating motions is guided by the guiding portion 80. At the same time, restore the basic orientation specified.

As shown in Fig. 11, the above-described projecting portion 26 is a columnar member that is provided from the right circumferential side surface of the distal end side needle bar 21 to the right side of the sewing machine (the front side of the eleventh figure).

As shown in Fig. 11, in the guide portion 80, a guide groove 80a is provided at a position in which the upper opening of the upper portion extends in the vertical direction. The guide groove 80a is composed of a portion in which the first guide groove 81 that is oriented in a different direction from the protruding portion 26 and that is disposed below the first guide groove and that is relatively narrow in the same direction as the protruding portion 26 Guide groove 82.

The first guide groove 81 is formed symmetrically in such a manner that the groove edges 81a on both sides are close to each other from the top to the bottom, and the groove width is narrow. As described above, when the needle bar 20 is moved downward from the top dead center, the protruding portion 26 slides on the groove edge 81a of the first guide groove 81, and is formed in any one of the left and right directions along the shape of the groove edge 81a. Guide to the bottom.

The second guide groove 82 is a constant groove width which is narrowed from the first guide groove 81 to the lower side. The groove width of the first guide groove 82 is only slightly larger than the diameter of the protruding portion 26. Thus, when the needle bar 20 is further moved downward, the protruding portion 26 guided by the first guiding groove 81 follows the second guiding The guide grooves 82, which remain in the same direction, continue to be guided to the lower side.

The working principle of the needle bar 20 and the needle 30 will be specifically described below. When the workpiece moves to the right along the curve, when the front end side needle bar 21 reaches the top dead center, the air receiving portion 25 receives the air ejected by the right side air ejecting portion 72, as shown in Fig. 12(a) As shown in the figure, the distal end side needle bar 21 starts to perform a self-axis rotational motion to the left around the axis G for reciprocating up and down. At this time, since the needle 30 also rotates to the left as the left side of the distal end side needle 21 rotates from the shaft, the pinhole 31 of the needle 30 is as shown in the lower drawing of Fig. 12(a). The upper line outlet 30a faces the front right side.

Next, when the needle bar 20 is moved downward from the top dead center, as shown in Fig. 12(b), the projection 26 slides on the groove edge 81a on the rear side of the first guide groove 81, and along the rear side. The shape of the groove edge 81a is turned to the right in turn and guided to the lower side. Therefore, the front end side needle bar 21 performs the self-axis rotation motion in the direction in which the original basic orientation is restored (in the present description, the right side around the axis G which reciprocates up and down), and the original basic orientation is sequentially restored. At this time, since the needle 30 also rotates to the right as the right side of the distal end side needle 21 rotates from the shaft, the upper thread outlet 30a of the needle hole 31 is as shown in the lower diagram of Fig. 12(b). Turn to the front in turn.

Next, when the needle bar 20 is further lowered to the bottom dead center, as shown in the upper diagram of FIG. 12(c), the protruding portion 26 guided by the first guiding groove 81 is maintained in the same direction along the second guiding groove 82. , continue to be guided below. Therefore, the front end side needle bar 21 is kept moving substantially to the bottom dead center. At this time, since the needle 30 also maintains its state in accordance with the substantially aligning of the distal end side needle bar 21, as shown in the lower drawing of Fig. 12(c), the upper thread outlet 30a of the pinhole 31 is also kept oriented. Positive state.

Thereby, at the bottom dead center where the up-and-down reciprocating motion is performed, as the distal end side needle bar 20 returns to the predetermined basic orientation, the upper thread outlet 30a of the pinhole 30a of the needle 30 faces the front side inside the kettle 40, and thus passes through The upper line of the pinhole 30 can be surely engaged with the lower line located inside the kettle 40.

On the other hand, as shown in the upper drawing of Figs. 13(a) and (b), when the needle bar 20 is moved upward from the bottom dead center, the protruding portion 26 is kept in the same direction along the second guiding groove 82, and is Guide to the top dead center. Therefore, the distal end side needle bar 21 is moved to the top dead center while being substantially aligned, and since the needle 30 is also maintained in the state in which the distal end side needle bar 21 is substantially aligned, as shown in Fig. 13 (a), (b) As shown in the following figure, the upper thread outlet 30a of the pinhole 31 is also maintained toward the front.

Then, when the front end side needle bar 21 reaches the top dead center, the air receiving portion 25 receives the air ejected by the right side air ejecting portion 72 again, as shown in the upper view of Fig. 13(c), the front end side needle bar 21 A self-axis rotational motion is performed to the left around the axis G that reciprocates up and down. At this time, since the needle 30 also rotates to the left as the left side of the distal end side needle 21 rotates from the shaft, the pinhole 31 of the needle 30 is as shown in the lower diagram of Fig. 13(c). The upper line outlet 30a faces the front right side.

Hereinafter, as the needle bar 20 reciprocates up and down, the above-described needle bar 20 and the needle 30 are also repeatedly moved.

Further, when the workpiece moves to the left along the curve, when the front end side needle bar 21 reaches the top dead center, the air receiving portion 25 receives the air ejected by the left side air ejecting portion 71, and the front end side needle bar 21 is A self-axis rotational motion is performed to the right around the axis G for reciprocating up and down. Therefore, when the needle bar 20 is moved 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 turns to the left side and is guided along the shape of the groove edge 81a. To the bottom. Therefore, the distal end side needle bar 21 is rotated from the axis in the direction in which the original basic orientation is restored (in the present description, the left side around the axis G for reciprocating up and down), and the original basic orientation is sequentially restored. At this time, since the needle 30 also rotates to the left as the left side of the distal end needle 21 rotates from the shaft, the upper thread outlet 30a of the needle hole 31 sequentially turns to the front side, and the subsequent operation is the same as described above.

Further, in the above-described embodiment, the configuration of the needle bar 20 is divided into a proximal end side needle bar 22 and a distal end side needle bar 21, and the needle bar 20 may be integrally formed without being divided.

Further, the needle bar 20 receives the air ejected from the air ejecting portion 70 before and after the top dead center of the vertical reciprocating motion, and may receive the air ejected from the air ejecting portion 70 during the ascending or descending movement.

Further, the air receiving portion 25 has a rectangular plate shape, and may be provided in another shape. Further, a concave surface 25a is provided on the right side surface 251 and the left side surface of the air receiving portion 25, and the concave surface 25a is not provided, and the right side surface 251 and the left side surface 252 may be provided flat.

Further, the air ejecting unit is provided in two upper and lower sides, that is, the right side air ejecting unit 71 and the left side air ejecting unit 72. You can set only one, or you can set more than three.

Further, the shape of the guiding portion 80 is not limited to the above-described shape, and any shape may be provided as long as the protruding portion 26 can be guided.

Further, in the present embodiment, the guide portion 80 guides the protruding portion 26 only when the needle bar 20 is moved downward. When the ascending motion is performed, by guiding the protruding portion 26, the protrusion 26 is guided along the guiding portion 80, so that the needle shaft (or the front end needle bar) is rotated around the axis of the vertical reciprocating motion. no problem.

The embodiments of the present invention have been described above with reference to the drawings. However, the present invention It is not limited to the illustrated embodiment. Various modifications and changes can be made to the embodiments shown in the drawings without departing from the scope of the invention.

10‧‧‧Sewing machine body

20‧‧‧ Needle bar

21‧‧‧ front end needle bar

22‧‧‧Based side needle bar

30‧‧‧ pinhole (line exit)

30a‧‧‧needle

40‧‧‧ kettle

50‧‧‧ Pressing board

t‧‧‧Online

Claims (10)

A sewing machine comprising a sewing machine body, a needle bar disposed on the machine body of the sewing machine, and a needle fixed to the needle bar, wherein the needle bar is in a sewing machine in which the needle bar and the needle are reciprocated up and down with respect to the sewing machine body The self-axis rotation motion is performed around the axis of the upper and lower reciprocating motion. The sewing machine according to claim 1, wherein the needle bar is composed of two parts: a front end side needle bar for fixing a needle on an upper and lower reciprocating axis, and a sewing machine body disposed on the coaxial line. The proximal end side needle bar; the front end side needle bar is rotated relative to the base end side needle bar around the axis of the upper and lower reciprocating motion. The sewing machine according to claim 2, wherein the needle bar connects the base end side needle bar and the front end side needle bar to each other by a joint member. The sewing machine according to claim 2, wherein the needle bar further includes an air ejecting portion that can eject air, and the needle bar is provided at an outer side of the needle bar in a diameter direction of the peripheral side thereof An air receiving portion that protrudes outward, and the air receiving portion receives the air ejected from the air ejecting portion, so that the needle bar can perform a self-axis rotational motion around an axis that reciprocates up and down. The sewing machine according to the fourth aspect of the invention, wherein the air ejecting unit includes: a right side air ejecting unit disposed on a right side of the air receiving unit of the needle bar; and a left side of the air receiving unit disposed on the needle bar a left air blowing portion; the air is ejected toward the right side of the air receiving portion of the needle bar by the right air ejecting portion, so that the needle bar performs a self-axis rotational motion to the left around the axis of the vertical reciprocating motion; Air is ejected toward the left side of the air receiving portion of the needle bar by the left air ejecting portion, so that the needle bar performs a self-axis rotational motion to the right around the axis of the reciprocating motion. The sewing machine according to claim 4, wherein the air ejecting portions are provided in parallel in the vertical direction. The sewing machine according to claim 4, wherein the air receiving portion is provided with a concave surface on the right side and/or the left side for receiving air ejected by the air ejecting portion. The sewing machine according to any one of claims 1 to 7, wherein the needle bar is further provided with a guiding portion for guiding the movement of the needle bar; wherein the needle bar of the needle bar on the side of the circumference thereof The outer side in the diametric direction is provided with an outwardly projecting protrusion, and when the needle bar is raised and/or lowered, the needle bar is surrounded by the axis of the upper and lower reciprocating motion as the protrusion is guided by the guiding portion Perform a self-axis rotation motion. The sewing machine according to claim 8, wherein the needle bar performs a self-axis rotation motion around an axis of reciprocating up and down as the protrusion is guided by the guiding portion during the descending movement. And restore its basic orientation at the bottom dead center. A needle bar for a sewing machine, characterized in that: the needle bar is composed of two main parts: one is a needle on the front end side of the axis for reciprocating the needle, and the other is disposed on the coaxial line. A base end side needle bar of the sewing machine body, wherein the front end side needle bar performs a self-axis rotational motion about an axis that reciprocates up and down with respect to the base end side needle bar.