JP2006087812A - Sewing machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve the tightness of stitches in respective left/right needle falling positions and to prevent the stitch skipping when a needle bar swings to a right needle swing position and to a left needle swing position. <P>SOLUTION: A zigzag chain stitch machine 1 having a rotating thread take-up lever 9 interlockedly connected to a main spindle so as to synchronously rotate therewith, and a needle swing mechanism 6 swinging a needle bar 10 is further provided with a crank formation member 12 relatively rotationally provided to the main spindle 4 at a spindle end part of the main spindle 4 and forming a needle bar crank, and a phase adjusting mechanism 20 capable of transmitting the rotation driving force of the main spindle 4 to the crank formation member 12, and adjusting the rotation phase of the crank formation member 12 to the main spindle 4 by being interlocked with the swing of the needle bar 10. The phase adjusting mechanism 20 is provided with an external tooth formation member 22 formed with a helical spline external tooth, an internal tooth formation member 21 formed with an helical spline internal tooth, and a horizontal movement transmission mechanism 23. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  In the present invention, the phase of the rotary balance that rotates in synchronization with the main shaft and the phase with respect to the main shaft of the needle bar that moves up and down in synchronization with the rotation of the main shaft It relates to the one that can be adjusted as appropriate by swinging the needle.

  2. Description of the Related Art Conventionally, a decorative sewing machine such as an eyelet perforated sewing machine, a double chain stitch sewing machine, a staggered sewing machine or the like is generally provided with a rotary balance that rotates in conjunction with a sewing machine main shaft. This type of rotary balance is formed in a substantially T-shape in front view having an upper thread hook portion, and in the middle of the thread path from the thread supply source to the sewing needle when rotating in synchronization with the main spindle of the sewing machine, Since a part of the upper thread fed from the source engages with the upper thread hook, the amount of thread taken by the rotary balance can be adjusted.

  By the way, the texture of stitches (the degree of stitch clogging) often changes depending on the type and thickness of the work cloth, as well as the type and thickness of the sewing thread. Accordingly, various types of rotary balance devices for sewing machines have been proposed in which the phase of the thread take-up amount curve by the rotary balance can be adjusted so as to be advanced or delayed so that the appearance of the texture can be arbitrarily changed.

For example, a rotary sewing machine for a sewing machine of a sewing machine disclosed in Patent Document 1 is a base disk attached concentrically with a sewing machine main shaft, a base disk rotating in the same direction and at the same angular speed as the main shaft, Several inner thread contact pins attached to the disk, one disk supported concentrically on the front surface of the base disk by the inner thread contact pins, and the number attached to the front surface of the disk And an outer sewing thread contact pin, and an adjustment fixing device that can adjust and fix the mounting angle of the disk with respect to the base disk. By adjusting the mounting angle, the shape of the change curve of the thread take-up amount is changed. It is adjusted so that the thread take-up action can be adapted to various sewing conditions.
Japanese Examined Patent Publication No. 37-17183 (pages 1 and 2, FIGS. 1 and 2)

  As described above, in the rotary sewing machine for a sewing machine described in Patent Document 1, the shape of the change curve of the sewing thread take-up is changed and adjusted by adjusting the mounting angle of the adjusting and fixing device. Alternatively, the appearance of stitching can be changed according to consumer preference.

  By the way, for example, in the case of a staggered sewing machine that forms a staggered stitch, the needle bar swings so that the needle drops alternately on the right side and the left side. For this reason, not only does the timing of the contact between the sword tip of the outer hook of the rotary hook and the eye of the sewing needle differ depending on the right policy swing position and the left policy swing position of the needle bar, but also the upper thread loop hooked on the sword tip. The timing for exiting the rotary hook is also different. In other words, when the rotation direction of the rotary hook is counterclockwise as viewed from the operator, the timing of encountering the stitch hole of the sewing needle and the timing of thread removal of the upper thread loop are earlier when the needle swings to the right. Slower when swinging left.

  However, the rotation phase of the rotary balance and the phase of the needle bar's vertical movement are basically set based on when the blade tip of the rotary hook comes to the approximate center of the needle swinging width. There is a problem in that the thread tightening at each of the left needle entry positions is not optimal in any case, and the stitching texture and appearance are poor.

  Furthermore, since the phase of the needle bar up-and-down movement with respect to the main axis is not adjustable, depending on the type and thickness of the sewing thread or when the sewing speed is high, the sewing needle and the tip of the needle meet. There are problems such as the timing being unstable and the possibility of skipping.

  The sewing machine according to claim 1, wherein the sewing machine has a needle swinging mechanism for swinging the needle bar, a crank forming member provided at the shaft end portion of the main shaft so as to be rotatable relative to the main shaft and forming a needle bar crank; And a phase adjusting mechanism capable of transmitting the rotational driving force of the main shaft to the crank forming member and adjusting the rotational phase of the crank forming member relative to the main shaft in conjunction with the needle swing of the needle bar.

  When the main shaft is rotated by the sewing machine motor, the crank forming member connected to the main shaft is rotated, and the rotational driving force of the crank forming member is transmitted to the needle bar and the balance connected to the crank forming member. Since the needle bar and the balance are driven by adjusting to the main shaft, a predetermined thread take-up curve by the balance with respect to the predetermined hook thread amount curve is obtained.

  By the way, when the rotation phase of the crank forming member with respect to the main shaft of the crank forming member is adjusted by the phase adjusting mechanism so as to advance the rotational phase with respect to the main shaft of the crank forming member in conjunction with the needle swing of the needle forming member, When the rotation is advanced so that the rotational phase relative to the main shaft of the crank forming member is delayed, the vertical movement phase of the needle bar is delayed from the conventional phase.

  According to a second aspect of the present invention, the sewing machine according to the first aspect of the invention relates to the main shaft of the needle bar and the rotary balance coupled to be synchronized with the main shaft of the sewing machine by adjusting the rotational phase of the crank forming member with respect to the main shaft. It is configured to adjust the phase.

  According to a third aspect of the present invention, there is provided the sewing machine according to the first or second aspect, wherein the phase adjusting mechanism includes a first engaging member and a second engaging member that are engaged with each other via a groove cam and a cam portion that engages with the groove cam. A first engaging member that is fixed to the crank forming member and is concentric with the axis of the main shaft, and is externally fitted so as to be movable in the axial direction of the main shaft. A second engagement member that is rotationally driven, and a horizontal movement transmission mechanism that transmits the needle movement horizontal movement of the needle bar base drive shaft of the needle movement mechanism to the second engagement member.

  According to a fourth aspect of the present invention, there is provided the sewing machine according to the third aspect, wherein the first engagement member is a first engagement tooth forming member formed with first helical spline engagement teeth concentric with the axis of the main shaft. The second engagement member is a second engagement tooth forming member having a second helical spline engagement tooth meshed with the first helical spline engagement tooth.

  According to a fifth aspect of the present invention, in the invention according to any one of the first to fourth aspects, the crank forming member is a crank balance weight.

  According to a sixth aspect of the present invention, in the sewing machine according to any one of the first to fifth aspects, the phase adjusting mechanism is configured such that when the rotation direction of the yarn catching hook is counterclockwise as viewed from the operator of the sewing machine, the needle bar is When the needle swings to the right, the rotational phase of the rotary balance and the needle bar is advanced, and when the needle bar swings to the left, the rotational phase of the rotary balance and the needle bar is delayed.

  According to a seventh aspect of the present invention, in the sewing machine according to any one of the first to fifth aspects, the phase adjusting mechanism is configured such that the needle bar moves to the left when the rotation direction of the yarn catching hook is clockwise when viewed from the operator of the sewing machine. When rotating the needle, the rotational phase of the rotary balance and the needle bar is advanced. When the needle bar swings the needle to the right, the rotational phase of the rotary balance and the needle bar is delayed.

  According to an eighth aspect of the present invention, in the invention according to any one of the third to seventh aspects, the horizontal movement transmission mechanism is configured such that the horizontal movement amount by the needle swing mechanism is set to the first engagement by a distance corresponding to the phase change amount of the rotary balance. It has a link mechanism that slides the combined member in the axial direction of the main shaft.

  According to the first aspect of the present invention, in the sewing machine having the needle swinging mechanism for swinging the needle bar, the crank forming member and the phase adjusting mechanism are provided. When adjusting the rotational phase of the crank forming member relative to the main shaft during needle swinging, the vertical movement phase of the needle bar can be advanced with respect to the conventional phase at the needle swinging center of the needle bar. It is possible to realize an optimal encounter timing for swinging the needle, and to reliably prevent skipping when swinging to the right.

  On the other hand, when the needle bar is adjusted to delay the rotational phase relative to the main shaft of the crank forming member when swinging to the left in conjunction with the needle swing of the needle bar, the vertical movement phase of the needle bar is adjusted to the needle swing center of the needle bar. Therefore, it is possible to achieve the optimum encounter timing for the left hand swing, and to reliably prevent the skipping of the left hand swing.

  According to the invention of claim 2, by adjusting the rotational phase of the crank forming member relative to the main shaft, the phase relative to the main shaft of the rotary scale and the needle bar that are interlocked and coupled to rotate synchronously with the main shaft of the sewing machine is adjusted. Therefore, simply adjusting the rotational phase of the crank forming member relative to the main shaft not only adjusts the rotational phase of the rotary balance and the main shaft of the needle bar, but also allows the vertical movement phase of the needle bar to be adjusted simultaneously. In addition to preventing jumps, it is possible to achieve optimum thread tightening for each of the left and right needle swings. Other effects similar to those of the first aspect are obtained.

  According to the invention of claim 3, the phase adjustment mechanism is a first engagement member and a second engagement member that are engaged with each other via a groove cam and a cam portion that engages with the groove cam, A first engagement member fixedly provided on the crank forming member and concentric with the axis of the main shaft, and a second engagement externally fitted so as to be movable in the axial direction of the main shaft and driven to rotate by the rotational driving force of the main shaft Since the combination member and the horizontal movement transmission mechanism for transmitting the needle movement horizontal movement of the needle bar base drive shaft of the needle swing mechanism to the second engagement member, the needle bar base drive shaft by the needle swing mechanism at the time of the needle swing is provided. When the second engagement member is moved in the axial direction of the main shaft by the horizontal movement of the needle swinging, the first engagement member that engages with the second engagement member via the groove cam and the cam portion is provided. The needle bar to the left and right of the needle bar is rotated clockwise or counterclockwise according to the amount of movement of the second engagement member. In synchronization with Ri, a rotational phase with respect to the main axis of the fixedly provided crank member in the first engagement member can be easily and reliably adjusted to the advanced side or the retarded side with a simple member structure. Other effects similar to those of the first or second aspect are achieved.

  According to the invention of claim 4, the first engagement member is a first engagement tooth forming member in which a first helical spline engagement tooth concentric with the axis of the main shaft is formed, and the second engagement member is Since it is the 2nd engagement tooth formation member which has the 2nd helical spline engagement tooth meshed with the 1st helical spline engagement tooth, the 2nd helical spline engagement tooth of these 2nd engagement tooth formation members, The phase adjustment of the rotary balance can be speeded up and smoothed by the engagement (engagement) of the engagement tooth forming member with the first helical spline engagement teeth.

  According to the invention of claim 5, since the crank forming member is a crank balance weight, even when the main shaft rotates at a high speed during sewing, vibration and noise are generated by the crank forming member that is the crank balance weight. Without this, stable high-speed rotation of the spindle can be realized. Other effects similar to those of any one of claims 1 to 4 can be achieved.

  According to the invention of claim 6, the phase adjusting mechanism is rotated when the needle bar swings rightward when the rotation direction of the yarn catching hook is counterclockwise as viewed from the operator of the sewing machine. Advance the rotation phase of the balance and needle bar, and when the needle bar swings to the left, the rotation phase of the rotation balance and needle bar is delayed, so the timing of thread removal from the thread catching hook of the upper thread loop is early When the needle is swung in the direction, the thread is fastened with the rotary balance, so that it is possible to achieve the optimum thread tightening for the right hand, and the needle bar's vertical movement phase advances and the needle tip of the stitch needle hole Since the timing of encountering with matches, it is possible to reliably prevent skipping when swinging the needle to the right.

  On the other hand, when the needle threading from the thread catching hook of the upper thread loop is delayed to the left, the thread tightening by the rotary balance is delayed, so it is possible to achieve the optimum thread tightening for the needle swinging to the left. At the same time, the vertical movement phase of the needle bar is delayed and the timing of encountering the sword tip of the eye of the sewing needle matches, so that it is possible to reliably prevent skipping when the needle is swung to the left. Other effects similar to those of any one of claims 1 to 5 can be achieved.

  According to a seventh aspect of the present invention, the phase adjusting mechanism is a rotary balance when the needle bar swings leftward when the rotation direction of the yarn catching hook is clockwise as viewed from the operator of the sewing machine. When the needle bar moves forward and the needle bar swings to the right, the rotation phase of the rotary balance and needle bar is delayed, so the thread catching hook rotation direction is clockwise when viewed from the operator. However, it is possible to realize the optimum thread tightening for the leftward needle swing and to achieve the optimum thread tightening for the rightward needle swing.

  In addition, when the needle is swung to the left, the needle bar's vertical movement phase advances, and the timing of encountering the sword tip of the eye of the sewing needle matches, so it is possible to reliably prevent skipping when the needle is swung to the left. This is possible, and when the needle swings to the right, the needle bar's vertical movement phase is delayed, and the timing of encountering the needle eye of the sewing needle eye coincides with each other. Can do. Other effects similar to those of any one of claims 1 to 5 can be achieved.

  According to an eighth aspect of the present invention, the horizontal movement transmission mechanism slides the first engagement member in the axial direction of the main shaft by a distance corresponding to the phase change amount of the rotary balance by the horizontal movement amount by the needle swing mechanism. Therefore, the horizontal movement amount can be easily changed to the distance corresponding to the phase change amount of the rotary balance, regardless of the horizontal movement amount by the needle swing mechanism. It is possible to realize the phase change of the rotary balance that is optimal for the bar swing width of the bar. Other effects similar to those of any one of claims 3 to 7 can be achieved.

  The staggered sewing machine of this embodiment includes a crank forming member formed as a needle bar crank of a needle bar vertical movement mechanism, an internal tooth forming member having helical spline internal teeth, an external tooth forming member having helical spline external teeth, and the like. The phase adjustment mechanism is provided, and the internal tooth forming member meshed with the external tooth forming member is horizontally moved in conjunction with the needle swinging of the needle bar, so that the phase of the rotary balance and the main shaft of the needle bar can be adjusted. It is.

  As shown in FIGS. 1 to 3, the main shaft 4 disposed in the left-right direction on the arm portion 2 of the staggered sewing machine 1 is rotatably supported at a plurality of locations on the machine frame 2 </ b> A, and the head 3 of the arm portion 2. Are provided with a needle bar up-and-down moving mechanism 5 that is connected to the left end of the main shaft 4 to drive the needle bar up and down, a needle swinging mechanism 6 that swings the needle bar left and right, and the like. 8 is provided. First, the needle bar vertical movement mechanism 5 will be briefly described.

  The needle bar 10 is supported by a U-shaped needle bar base 11 that is supported by the machine frame 2A so as to be movable in the left-right direction, and can be moved up and down. On the other hand, a crank forming member 12 (a crank balancing weight that forms a needle bar crank) 12 having a connecting pin 12a is fixed to the left end connecting portion 4a of the main shaft 4, and the needle bar crank is connected to the connecting pin 12a. An upper end portion of the rod 13 is pivotally attached to be rotatable.

  A horizontal slide pin 14 is supported at the lower end of the needle bar crank rod 13 so as to be slidable in the left-right direction, and the left end (tip) of the slide pin 14 is fixed to the vicinity of the upper end of the needle bar 10. 15 is connected.

  Next, since the needle swing mechanism 6 has a general configuration, it will be briefly described. The needle swing mechanism 6 is connected to a needle swing motor (not shown) formed of a stepping motor, a needle bar base drive shaft 17 connected to the needle swing motor, a slide pin 14, and a needle bar base drive shaft 17. It has a needle bar base 11 and the like.

  When the needle swinging motor is driven in the forward direction, as shown in FIGS. 2 and 4, since the needle bar base drive shaft 17 swings horizontally by a predetermined distance to the right, the slide pin 14 slides to the right. However, the needle bar base 11 and the needle bar 10 simultaneously swing to the right hand swing position.

  When the needle swinging motor is driven in reverse, as shown in FIGS. 3 and 5, the needle bar base drive shaft 17 swings horizontally by a predetermined distance to the left, so that the slide pin 14 slides to the left. The needle bar base 11 and the needle bar 10 simultaneously swing to the left swing position.

  By the way, a key member 18 facing left and right is fixed in a protruding manner to one end of the outer peripheral portion of the left end connecting portion 4a of the main shaft 4 described above. Therefore, as will be described later, an internal tooth forming member 21 having a key groove that engages with the key member 18 (this corresponds to the second engaging member), and an external tooth forming member 22 that engages with this (this is the first engaging member). The rotational driving force of the main shaft 4 is transmitted to the crank forming member 12 via the engagement member), and the crank forming member 12 is rotationally driven as a needle bar crank.

  Next, the phase adjustment mechanism 20 will be described. As shown in FIGS. 2, 3, and 6, the phase adjusting mechanism 20 includes an internal tooth forming member 21 (which is a second helical spline engaging tooth) on which a helical spline internal tooth 21 b (this corresponds to a second helical spline engaging tooth) is formed. And a helical spline external tooth 22a (which corresponds to the first helical spline engaging tooth) meshing with the internal tooth forming member 21 is formed. The external tooth formation member 22 (this is the first engagement member and corresponds to the first engagement tooth formation member) and the needle swing horizontal movement of the needle bar base drive shaft 17 of the needle swing mechanism 6 are formed as internal teeth. A horizontal movement transmission mechanism 23 for transmitting to the member 21 is provided.

  The internal tooth forming member 21 has helical spline internal teeth 21b concentric with the axis of the main shaft 4 on the inner peripheral portion of the annular tooth forming portion 21a, and the lead angle with respect to the axis of the main shaft 4 is viewed from the left. Thus, helical spline inner teeth 21b having a predetermined angle (for example, about 9 °) are formed counterclockwise.

  The inner tooth forming member 21 is fitted into the left end connecting portion 4a, and the left end connecting portion 4a is moved to the left end connecting portion 4a through the right end of the inner tooth forming member 21 through the annular support wall 21c. It is fitted. Further, a key groove 21d facing in the left-right direction is formed at one place on the inner peripheral side of the support wall 21c, and is engaged with the key member 18 of the left end connecting portion 4a so as to be movable in the left-right direction.

  On the other hand, the external tooth forming member 22 having the helical spline external teeth 22a formed on the outer peripheral portion meshes with the internal tooth forming member 21 from the left side, and the left end connecting portion 4a is connected to the cylindrical connecting concave portion 22b formed inside thereof. Is inserted from the right side, and the external teeth forming member 22 is connected to the left end connecting portion 4a of the main shaft 4 so as to be rotatable relative to the left end connecting portion 4a of the main shaft 4 by the fastening force of the stepped fixing screw 24. And the crank forming member 12 are substantially integrated.

  As shown in FIG. 2, the inner tooth forming member 21 is parallel to the axis of the main shaft 4 as shown in FIG. 2 with respect to the outer tooth forming member 22 supported by the left end connecting portion 4 a of the main shaft 4 so as to be relatively rotatable. When sliding to the rightward movement position, the internal tooth forming member 21 cannot be rotated independently via the key member 18 and the key groove 21d with respect to the left end connecting portion 4a, so the helical spline inner teeth 21b and the helical spline outer teeth 22a. As shown in FIG. 1, the external tooth forming member 22 and the crank forming member 12 fixed to the external tooth forming member 22 rotate clockwise as viewed from the left to advance the vertical movement phase of the needle bar 10 (see FIG. 1). 2 dash-dot line and FIG. 8).

  On the contrary, the inner tooth forming member 21 is parallel to the axis of the main shaft 4 as shown in FIG. 3 with respect to the outer tooth forming member 22 supported so as to be rotatable relative to the left end connecting portion 4a of the main shaft 4. When sliding to the leftward movement position, the internal tooth forming member 21 cannot rotate independently with respect to the left end connecting portion 4a via the key member 18 and the key groove 21d, so the helical spline inner teeth 21b and the helical spline outer teeth 22a. , The external tooth forming member 22 and the crank forming member 12 fixed to the external tooth forming member 22 rotate counterclockwise as viewed from the left, thereby delaying the vertical movement phase of the needle bar 10 with respect to the main shaft 4. (See the solid line in FIG. 1 and FIG. 8).

  By the way, as shown in FIGS. 1-3, the balance support member 26 is fixed to the left end portion of the connecting pin 12a, and the circular cover plate 27 is fixed to the side surface side of the balance support member 26 with a plurality of fixing screws 27a. ing. The cover plate 27 is loosely fitted in a circular opening 28a formed in a face plate 28 fixed to the end of the machine casing 2A. The base end 9 a of the rotary balance 9 is fixed to the cover plate 27 with a plurality of fixing screws 29.

  As shown in FIGS. 1 to 3, the rotary balance 9 includes a rotary arm portion 9 b extending from the base end portion 9 a, an upper thread holding portion 9 c of the tip end portion, and the like, and the base end portion 9 a and the rotary arm portion 9b, a first upper thread holding point 9d and a second upper thread holding point 9e are formed. As shown in FIGS. 2 and 3, a balance cover 30 is provided on the head 3 so that the upper thread 40 hooked on the upper thread holding portion 9 c of the rotary balance 9 does not come off.

  The balance cover 30 is formed with a balance recess 30a. Therefore, the balance cover 30 is fixed to the face plate 28 with a fixing screw 31 via a cylindrical support member 28b formed on the face plate 28, and the upper thread holding portion 9c of the rotary balance 9 rotates in the balance recess 30a. The upper thread 40 is prevented from coming off from the upper thread holding portion 9c during sewing.

  Next, the horizontal movement transmission mechanism 23 will be described. This horizontal movement transmission mechanism 23 forms internal teeth by a distance (for example, about 8 mm) corresponding to a phase change amount (for example, about 8 °) of the rotary balance 9 and the needle bar 10 by the horizontal movement amount by the needle swing mechanism 6. The member 21 is configured to slide in the axial direction of the main shaft 4.

  As shown in FIGS. 2 and 3, a connecting block 35 is fixed to the upper end portion of the needle bar base 11, and a roller 36 is rotatably attached to the connecting block 35, and is formed on the internal tooth forming member 21. The groove 21e is engaged from below. Therefore, when the maximum needle swing amount of the needle bar 10 is 8 mm, the sliding amount of the internal tooth forming member 21 is also about 8 mm through the engagement of the roller 36 and the annular groove 21e.

  As a result, since the lead angles of the helical spline outer teeth 22a and the helical spline inner teeth 21b are about 9 °, respectively, the inner tooth forming member 21 is in the right direction parallel to the axis of the main shaft 4 with respect to the outer tooth forming member 22. When sliding to the moving position by about 8 mm, the external tooth forming member 22 rotates about 8 ° clockwise as viewed from the left, and advances the rotation phase of the rotary balance 9 and the needle bar 10 relative to the main shaft 4 by 8 °. Make it.

  On the other hand, when the internal tooth forming member 21 slides about 8 mm to the left movement position parallel to the axis of the main shaft 4 with respect to the external tooth forming member 22, the external tooth forming member 22 is counterclockwise as viewed from the left. And the rotational phases of the rotary balance 9 and the needle bar 10 with respect to the main shaft 4 are respectively delayed by 8 °.

  Next, the operation of the staggered sewing machine 1 configured as described above will be described.

  As shown in FIG. 1, at the start of sewing, the upper thread 40 extending from a thread spool (not shown) passes through the first thread guide member 37 provided on the face plate 28, and then the rotating arm 9 b or the upper thread 40 holding section of the rotary balance 9. After being hooked on 9c, the upper threading is performed along a predetermined thread path through the second thread guide member 38, through the needle bar thread guide (not shown) to the eye hole 7a of the sewing needle 7. .

  When the sewing start switch is operated after the preparation for sewing is completed, the spindle 4 is rotated in a predetermined rotational direction by a sewing motor (not shown), so that the needle bar 10 is moved via the needle bar vertical movement mechanism 5. And the rotational driving force of the main shaft 4 is transmitted to the inner tooth forming member 21, the outer tooth forming member 22, and the crank forming member 12 in order, and the rotary balance 9 is synchronized with the main shaft 4. Driven by rotation. At the same time, the needle bar 10 is alternately switched between the left policy swing position and the right policy swing position by the needle swing mechanism 6. Therefore, zigzag stitches are sequentially formed on the work cloth by cooperation with the sword tip 8a provided on the outer hook of the rotary hook 8 provided on the bed portion of the staggered sewing machine 1.

  In this case, when the rotation direction of the rotary hook 8 is counterclockwise when viewed from the operator of the staggered sewing machine 1, the needle bar 10 swings rightward by the needle swing mechanism 6 (see FIGS. 2 and 4). ), The timing at which the upper thread loop extending from the eye hole 7a of the sewing needle 7 comes out of the rotary hook 8 is accelerated. Therefore, as described above, the internal tooth forming member 21 slides by about 8 mm to the right moving position via the horizontal movement transmission mechanism 23 when the needle is swung to the right, so that the external tooth forming member 22 is moved from the left. The phase of the crank forming member 12 fixedly connected to the external tooth forming member 22 is advanced by about 8 °.

  As a result, as shown in FIG. 8, the vertical movement phase of the needle bar 10 is advanced by about 8 ° (phase advance) with respect to the conventional vertical movement phase (reference) at the center of needle bar swing. ) Is obtained. In addition to this, the phase of the rotary balance 9 fixed to the crank forming member 12 via the balance support member 26 is also advanced by about 8 °. Therefore, as shown in FIG. A balance take-up amount curve (phase advance) obtained by advancing a predetermined phase (about 8 °) with respect to the amount curve (reference) is obtained.

  On the other hand, when the needle bar 10 swings to the left by the needle swing mechanism 6 (see FIGS. 3 and 5), the timing at which the upper thread loop extending from the eye hole 7a of the sewing needle 7 comes out of the rotary hook 8 is delayed. Therefore, as described above, the internal tooth forming member 21 slides by about 8 mm to the left movement position via the horizontal movement transmission mechanism 23, so that the external tooth forming member 22 rotates counterclockwise as viewed from the left. And the phase of the crank forming member 12 fixed to the external tooth forming member 22 is delayed by about 8 °.

  As a result, as shown in FIG. 8, the vertical movement phase (phase delay) in which the vertical movement phase of the needle bar 10 is delayed by about 8 ° with respect to the conventional vertical movement phase (reference) at the center of needle bar swing. Is obtained. In addition, since the phase of the rotary balance 9 fixed to the crank forming member 12 via the balance support member 26 is also delayed by about 8 °, as shown in FIG. A take-up thread curve (phase delay) delayed by a predetermined phase (about 8 °) with respect to the curve (reference) is obtained.

  Here, the change of the needle bar 10 to the left and right needle swing positions by the needle swing mechanism 6 is executed near the uppermost position of the needle bar 10, and the vertical movement phase of the needle bar 10 is changed at that time point. There is no problem at each stitch where the staggered stitch is formed while performing the needle swing.

  In this manner, in the staggered sewing machine 1 having the rotary balance 9 interlocked and coupled so as to rotate synchronously with the main shaft 4 of the staggered sewing machine 1 and the needle swinging mechanism 6 that swings the needle bar 10, the crank forming member 12 and Since the phase adjusting mechanism 20 is provided, when the needle bar 10 is adjusted so as to advance the rotational phase of the crank forming member 12 with respect to the main shaft 4 during the right hand swing, 10 vertical movement phases can be advanced with respect to the conventional phase at the center of needle swing, and the optimal encounter timing for right hand swing can be realized. Flying can be prevented reliably.

  On the other hand, when the needle bar 10 is adjusted so as to delay the rotation phase of the crank forming member 12 with respect to the main shaft 4 when swinging the needle to the left in conjunction with the needle swing of the needle bar 10, the vertical movement phase of the needle bar 10 is changed to the needle swing. The phase can be delayed with respect to the conventional phase at the center, and the optimum encounter timing for the left hand swing can be realized, and the skipping at the time of the left hand swing can be surely prevented.

  Further, the phase adjusting mechanism 20 is fixed to the crank forming member 12 and meshed with an external tooth forming member 22 formed with helical spline external teeth 22a concentric with the axis of the main shaft 4, and the helical spline external teeth 22a. An internal tooth forming member 21 which has the helical spline inner teeth 21b and is externally fitted so as to be movable in the axial direction of the main shaft 4 and is rotationally driven by the rotational driving force of the main shaft 4, and the needle bar base of the needle swing mechanism 6 Since the horizontal movement transmission mechanism 23 for transmitting the horizontal movement of the drive shaft 17 to the internal gear forming member 21 is provided, the internal movement of the needle bar drive shaft 17 by the horizontal movement of the needle bar base drive shaft 17 by the needle movement mechanism 6 during the needle movement is provided. When the tooth forming member 21 is moved in the axial direction of the main shaft 4, the external tooth forming member 22 having the helical spline external teeth 22a meshing with the helical spline internal teeth 21b of the internal tooth forming member 21 is formed. In order to rotate clockwise or counterclockwise according to the movement amount of the tooth forming member 21, a crank formation fixedly provided on the external tooth forming member 22 in synchronization with the needle swinging of the needle bar 10 to the left and right. The rotation phase of the member 12 with respect to the main shaft 4 can be easily and reliably adjusted to the advance side or the delay side with a simple member configuration.

  Further, the phase adjusting mechanism 20 is arranged so that when the needle bar 10 swings the needle to the right when the rotation direction of the rotary hook 8 is counterclockwise when viewed from the operator of the staggered sewing machine 1, the rotary balance 9 and the needle When the rotational phase of the bar 10 is advanced and the needle bar 10 swings the needle to the left, the rotational phase of the rotary balance 9 and the needle bar 10 is delayed, so that the timing of thread removal from the rotary hook 8 of the upper thread 40 is early. When the needle is swung in the direction, the thread tightening by the rotary balance 9 is accelerated, so that it is possible to realize the optimum thread tightening for the right hand swinging, and the needle bar 10 moves further up and down, and the stitches of the sewing needle 7 are advanced. Since the meeting timing of the hole 7a with the sword tip coincides, it is possible to surely prevent skipping when the needle swings to the right.

  On the other hand, when the needle threading of the upper thread 40 from the rotary hook 8 is delayed to the left, the thread tightening by the rotary balance 9 is delayed, so that the optimum thread tightening for the needle swinging to the left can be realized. Furthermore, since the vertical movement phase of the needle bar 10 is delayed and the timing of encountering the sword tip of the eye hole 7a of the sewing needle 7 is matched, it is possible to reliably prevent skipping when the needle is swung to the left.

  Next, a modified embodiment in which the embodiment is partially modified will be described.

  1] As shown in FIG. 10, one or a plurality of (for example, four) spiral groove cams 22c are formed at equal intervals on the outer periphery of the external tooth forming member 22A, and the inner periphery of the internal tooth forming member 21A. One or a plurality of (for example, four) spiral cam portions 21f that can be engaged with the groove cams 22c are formed in the portion, and the internal tooth forming member 21A and the like are formed via the groove cams 22c and the cam portions 21f. The external tooth forming members 22A may be engaged with each other. Moreover, you may make it comprise the cam part 21f with a pin member.

  Further, one or a plurality of (for example, four) helical cam portions are formed on the outer peripheral portion of the external tooth forming member 22A, and one or a plurality (for example, four) are formed on the inner peripheral portion of the internal tooth forming member 21A. ), And the inner tooth forming member 21A and the outer tooth forming member 22A may be engaged with each other through the groove cam and the cam portion. Moreover, you may make it comprise a cam part with a pin member.

  2] While increasing the lead angle of the helical spline outer teeth 22a and the helical spline inner teeth 21b to about 27 °, respectively, a link mechanism 45 is additionally provided in the horizontal movement transmission mechanism 23 of the inner tooth forming member 21, and the link mechanism 45, the sliding amount of the internal tooth forming member 21 is reduced to about 3 mm with respect to the maximum needle swing amount (about 8 mm), and the vertical movement phase of the needle bar 10 and the rotation phase of the rotary balance 9 are adjusted by 8 °. You may comprise as follows.

  The horizontal movement transmission mechanism 23 causes the internal gear forming member 21 to move the horizontal movement amount by the needle swing mechanism 6 by a distance (for example, about 3 mm) corresponding to the phase change angle (for example, about 8 °) of the rotary balance 9. 4 has a link mechanism 45 that slides in the axial direction.

  That is, as shown in FIGS. 11 and 12, the connecting pin 46 is fixed to the upper end portion of the needle bar base 11, and is pivotally supported by the pivot pin 47 on the machine frame 2 </ b> A on the rear side of the needle bar base 11. The connecting pin 46 is fitted into a bifurcated portion 48 a formed at the front end portion of the first link 48 formed. A second link 49 arranged in the front-rear direction is pivotally supported by the pivot pin 50 at the center in the longitudinal direction on the machine frame 2A immediately behind the needle bar base 11, and the first link. The rear end of 48 and the rear end of the second link 49 are connected to both ends of the third link 53 by connecting pins 51 and 52, respectively.

  A roller 54 is pivotally attached to the front end portion of the third link 53 and is engaged with an annular groove portion 21e formed in the internal tooth forming member 21 from below. Here, the ratio of the distance from the pivot pin 47 to the connection pin 46 of the first link 48 and the distance from the pivot pin 47 to the connection pin 52 is about 2.7: 1, and the maximum needle swing amount of the needle bar 10 is If it is 8 mm, the sliding amount of the internal tooth forming member 21 is about 3 mm.

  As a result, by setting the lead angle of the helical spline outer teeth 22a and the helical spline inner teeth 21b to be about 27 °, the inner tooth forming member 21 is moved to the right in parallel to the axis of the main shaft 4 with respect to the outer tooth forming member 22. When the outer tooth forming member 22 is slid by about 3 mm to the lateral movement position, the external tooth forming member 22 is rotated about 8 ° clockwise as viewed from the left, and the rotation phase of the rotary balance 9 relative to the main shaft 4 is advanced by 8 °.

  On the contrary, when the internal tooth forming member 21 slides about 3 mm to the left movement position parallel to the axis of the main shaft 4 with respect to the external tooth forming member 22, the external tooth forming member 22 is opposite from the left side. It rotates about 8 ° clockwise and delays the rotation phase of the rotary balance 9 relative to the main shaft 4 by 8 °. Here, the first to third links 48, 49, 53, the pivot pins 47, 50, the connecting pins 46, 51, 52, and the like constitute a link mechanism 45.

  Thus, the horizontal movement transmission mechanism 23 is a link mechanism that slides the external tooth forming member 22 in the axial direction of the main shaft 4 by a distance corresponding to the phase change amount of the rotary balance 9 by the horizontal movement amount by the needle swing mechanism 6. 45, regardless of the horizontal movement amount by the needle swing mechanism 6, the horizontal movement amount can be easily changed to a distance corresponding to the phase change amount of the rotary balance 9, depending on the configuration of the link mechanism 45. The phase change of the rotary balance 9 that is optimal for the needle swing width of the needle bar 10 can be realized.

  3) The rotary balance is connected via the external tooth forming member 22 having the helical spline external teeth 22a engaged with the internal teeth forming member 21 having the helical spline internal teeth 21b to the balance support member 26. 9 is fixed, the lead angles of the helical spline inner teeth 21b and the helical spline outer teeth 22a are set as appropriate, and the inner tooth forming member 21 is slid in the left-right direction by the horizontal movement of the needle bar base drive shaft 17 by swinging the needle. The phase of the rotary balance 9 adjusted by the phase adjustment mechanism 20 is independent of the phase adjustment of the vertical movement of the needle bar 10, and the balance phase adjustment mechanism 20 comprising the internal tooth forming member 21, the external tooth forming member 22 and the like. May be finely adjusted.

  4] The internal tooth forming member 21 may be directly driven by a solenoid or an air cylinder, or may be driven by an electric actuator such as a stepping motor or a DC servo motor.

  5] When DLC coating (diamond-like carbon coating) is applied to helical spline inner teeth 21b, helical spline outer teeth 22a, groove cam 22c, cam portion 25f, etc., the drive is smaller due to the low friction coefficient effect of DLC coating. The internal tooth forming members 21 and 21A can be slid by force.

  6) Needless to say, the present invention can be applied to various types of sewing machines having a rotary balance, such as an eyelet sewing machine for forming an eyelet sewing machine, a decorative sewing machine, and the like.

It is the side view of the head which removed the balance cover of the staggered sewing machine which concerns on the Example of this invention. It is a front view which shows the internal structure (right policy swing state) of the head of a staggered sewing machine. It is a front view which shows the internal structure (left policy swing state) of the head of a staggered sewing machine. It is a rear view of a needle bar and a rotary hook that are swung to the right. It is a rear view of the needle bar and the rotary hook that are swung to the left. It is a disassembled perspective view of a main shaft, an internal tooth formation member, and an external tooth formation member. It is a table | surface explaining the correlation of the needle swing of a needle bar, the phase of a rotary balance, and the phase of a needle bar. It is a diagram which shows the up-and-down movement curve of the needle bar at the time of the left and right needle swing. It is a diagram which shows a shuttle thread amount curve and a balance thread take-up amount curve when swinging left and right. FIG. 7 is a diagram corresponding to FIG. 6 according to a modified embodiment. FIG. 4 is a view corresponding to FIG. 3 provided with a link mechanism. It is a top view of a link mechanism.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Staggered sewing machine 4 Main shaft 6 Needle swing mechanism 8 Rotary hook 9 Rotary balance 10 Needle bar 12 Crank forming member 17 Needle bar base drive shaft 20 Phase adjustment mechanism 21 Internal tooth forming member 21b Helical spline internal tooth 21f Cam part 22 External tooth formation Member 22a Helical spline external teeth 22c Groove cam 23 Horizontal movement transmission mechanism 45 Link mechanism

Claims (8)

In a sewing machine having a needle swing mechanism that swings a needle bar,
A crank forming member provided at a shaft end portion of the main shaft so as to be rotatable relative to the main shaft and forming a needle bar crank;
A phase adjusting mechanism capable of transmitting the rotational driving force of the main shaft to the crank forming member and adjusting the rotational phase of the crank forming member with respect to the main shaft in conjunction with needle swinging of a needle bar;
A sewing machine characterized by comprising:   The rotation shaft with respect to the main shaft of the crank forming member is adjusted so as to adjust the phase with respect to the main shaft of the needle bar and the rotary balance coupled to be synchronized with the main shaft of the sewing machine. Item 2. The sewing machine according to Item 1. The phase adjustment mechanism includes:
A first engaging member and a second engaging member that are engaged with each other via a groove cam and a cam portion that engages with the groove cam, the shaft being fixedly provided on the crank forming member and the axis of the main shaft A first engagement member concentric with the second engagement member, and a second engagement member that is externally fitted so as to be movable in the axial direction of the main shaft and is rotationally driven by the rotational driving force of the main shaft,
A horizontal movement transmission mechanism for transmitting the needle movement horizontal movement of the needle bar base drive shaft of the needle movement mechanism to the second engagement member;
The sewing machine according to claim 1 or 2, further comprising:   The first engagement member is a first engagement tooth forming member formed with a first helical spline engagement tooth concentric with the axis of the main shaft, and the second engagement member is the first helical spline engagement. The sewing machine according to claim 3, wherein the sewing machine is a second engagement tooth forming member having second helical spline engagement teeth meshing with the teeth.   The sewing machine according to claim 1, wherein the crank forming member is a balance weight for a crank.   The phase adjusting mechanism advances the rotational phase of the rotary balance and the needle bar when the needle bar swings to the right when the thread catching hook is rotating counterclockwise as viewed from the operator of the sewing machine. The sewing machine according to any one of claims 1 to 5, wherein when the needle bar swings leftward, the rotational phase of the rotary balance and the needle bar is delayed.   The phase adjusting mechanism advances the rotational phase of the rotary balance and the needle bar when the needle bar swings to the left when the thread catching hook is rotating clockwise when viewed from the operator of the sewing machine. The sewing machine according to any one of claims 1 to 5, wherein when the needle bar swings to the right, the rotational phase of the rotary balance and the needle bar is delayed. The horizontal movement transmission mechanism includes a link mechanism that slides the first engagement member in the axial direction of the main shaft by a distance corresponding to a phase change amount of the rotary balance by a horizontal movement amount by the needle swing mechanism. The rotary balance device for a sewing machine according to any one of claims 3 to 7,