JPH09239174A - Sewing machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To smooth preparations for a sewing process at the start thereof, and ensure the proper formation of a beautiful seam by performing a thread cutting operation at the start of the sewing process. SOLUTION: A control means controls a drive means so that a thread cutting mechanism operates to cut thread at the time of starting a sewing process (step 14). Consequently, when needle thread extended from the eye of a sewing needle is continuous to a processing cloth at the time of staring the sewing process, or even when a needle thread remnant from the eye to a needle thread end is long, the needle thread is cut to a remnant of suitable length. According to this construction, the needle thread end after cut is not tangled with a thread loop arresting hook, or not sewn into the reverse side of the processing cloth in the next and succeeding operations, thereby ensuring that sewing preparations are smoothed at the start of the sewing process, or a beautiful seam is formed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sewing machine provided with a thread cutting mechanism, and in particular, regardless of whether the upper thread is broken or not.
The present invention relates to a thread-cutting operation that is performed at the start of sewing to prevent entanglement of an upper thread into a hook for catching an annulus at the start of sewing and bird's nest sewing into a work cloth.

[0002]

2. Description of the Related Art Conventionally, a sewing machine main body of a normal sewing machine is mainly composed of a bed portion, a pedestal portion, an arm portion, and a head portion, and a main shaft driven by a sewing machine motor is arranged in the arm portion. The needle bar, the sewing needle, and the balance of the section are driven up and down by the driving force of the main shaft. Further, a lower shaft and a thread wheel catching shuttle that cooperates with the sewing needle are arranged in the bed portion, and the lower shaft is also rotationally driven by the driving force from the main shaft. Since the sewing needle and the shuttle for catching the thread wheel need to be operated synchronously, the lower shaft is driven by the main shaft in the conventional sewing machine.

Here, in this type of lower shaft interlocking type general sewing machine, the upper thread loop formed in the thread catching hook is caught at a predetermined timing, and temporarily from that timing for a predetermined period. A needle thread holding mechanism (a so-called picker mechanism) that is configured to catch the yarn is provided adjacent to the yarn wheel catching hook. That is, the upper thread holding mechanism is provided with an upper thread catching member that swings so as to catch the upper thread loop,
During the ascending period of the balance at the start of sewing, the needle thread catching member is actuated to temporarily catch the needle thread loop,
By pulling the upper thread end toward the thread catcher hook through the work cloth and the needle hole of the needle plate, the upper thread end does not come out of the eyelet hole of the sewing needle, and the upper thread end is under the work cloth. By pulling it to the side, the sewing process can be performed without the thread being pulled out, and the work of terminating the upper thread end protruding to the upper side of the work cloth can be omitted.

By the way, for example, Japanese Patent Laid-Open No. 60-2175.
No. 0 and Japanese Patent Application Laid-Open No. 3-234291, by driving the yarn wheel catching hook with a dedicated drive motor independently of the sewing machine spindle, the yarn wheel catching hook is driven synchronously with the sewing machine spindle. A lower shaft independent drive type sewing machine has been proposed in which the momentary rotation state of the thread catcher hook is controlled in accordance with the sewing conditions. In this type of lower shaft independent drive type sewing machine as well, similarly, an upper thread holding mechanism is provided so that the upper thread end at the start of sewing is pulled below the work cloth.

[0005]

As described above, in the lower shaft interlocking type sewing machine provided with the upper thread holding mechanism and the lower shaft independent drive type sewing machine, the upper thread end at the start of sewing is put under the work cloth. Since it is designed to be pulled to the side, for example, when sewing embroidery data with a multi-head type embroidery sewing machine, when thread breakage occurs in only one or a few embroidery sewing machines and sewing stops at the same time, thread breakage occurs. With respect to the embroidery sewing machine in which the threading occurs, thread the thread and thread the threaded end of the threaded upper thread onto the needle bar case or hold it with the operator's hand. When the sewing is resumed with the hole prevented from coming off, the needle thread holding mechanism provided on each head simultaneously operates.

That is, since the needle thread holding mechanism operates when the sewing is resumed, in the embroidery sewing machine in which thread breakage occurs, the needle thread end is caught in the needle bar case, or the operator holds it by hand. Therefore, the shortage of the upper thread due to the operation of the upper thread holding mechanism is unwound excessively from the thread spool, causing slack in the lower side of the needle plate, and the loose upper thread is put in the race section of the thread catcher hook. When tangled, the rotation of the sewing machine stops and sewing cannot be resumed, or the loose needle thread is sewn on the back side of the work cloth in a bird's nest shape and a beautiful seam cannot be formed. I have a problem. Similarly, with respect to an embroidery sewing machine in which thread breakage did not occur, excess needle thread fed out by the operation of the needle thread holding mechanism is loosened below the needle plate and similarly entangled in the thread catcher hook. However, there is a problem that it is sewn in the shape of a bird's nest on the back side of the work cloth.

SUMMARY OF THE INVENTION An object of the present invention is to provide a sewing machine which executes a thread cutting operation at the start of sewing, thereby facilitating the sewing process at the start of sewing and ensuring a clean stitch formation. .

According to a first aspect of the present invention, there is provided a sewing machine including a sewing needle driven by a sewing machine motor via a main shaft, a hook for catching a thread wheel that cooperates with the sewing needle to catch a thread wheel, and a thread wheel catcher. In a sewing machine including a shuttle drive mechanism that rotationally drives a shuttle using a drive force of a sewing machine motor, and a thread cutting mechanism that cuts a thread on the lower side of the needle plate, a drive unit that drives the thread cutting mechanism, and a sewing machine at the start of sewing. The thread cutting mechanism is provided with control means for controlling the driving means so that the thread cutting operation is performed.

The operation will be described. Since the control means controls the driving means so that the thread trimming mechanism operates to perform the thread trimming operation at the start of sewing, the driving means drives the thread trimming mechanism. Even when the upper thread extending from the eyelet is connected to the work cloth, or when the upper thread remaining amount from the eyelet to the upper thread end is long, this thread cutting mechanism allows
Since the upper thread extending from the eyelet is cut so that the remaining amount of the upper thread has an appropriate length, after the next sewing operation, the upper thread end after cutting is entangled with the thread catcher and Since the back side of the cloth is not sewn, smoothing of the sewing process at the start of sewing and reliable formation of beautiful stitches can be achieved.

According to a second aspect of the present invention, a sewing machine includes a sewing needle and a balance which are driven by a sewing machine motor via a main shaft, a thread wheel catching hook which catches a thread wheel in cooperation with the sewing needle, and a thread wheel catching hook. In a sewing machine including a hook drive motor that is rotationally driven independently of a motor in synchronization with a main shaft, and a thread cutting mechanism that cuts a thread on a lower side of a needle plate, a driving unit that drives the thread cutting mechanism, and a sewing start At the same time, the thread cutting mechanism is provided with a control means for controlling the driving means so that the thread cutting mechanism operates.

The operation will be described. Since the control means controls the drive means so that the thread trimming mechanism operates the thread trimming operation at the start of sewing, the drive means drives the thread trimming mechanism. To do.

According to a third aspect of the present invention, in the first or second aspect of the present invention, the drive means includes an actuator independent of the sewing machine motor. To explain the operation, the drive means drives the thread trimming mechanism with an actuator independent of the sewing machine motor, so that the thread trimming load associated with the thread trimming operation does not act on the sewing machine motor when the main shaft, the sewing needle and the balance are driven. The size of the sewing machine motor can be reduced.

According to a fourth aspect of the present invention, in the invention of the third aspect, the control means controls the driving means so that the thread cutting mechanism operates the thread cutting operation while the needle bar is being raised in the second cycle from the start of sewing. It is a thing. Explaining the operation, even if a needle bar jump mechanism is provided and the needle bar is configured to jump to its uppermost position at the end of sewing in the sewing process, the needle bar will become a needle bar drive mechanism in the second cycle from the start of sewing. Be connected. Then, the control means controls the drive means so that the thread trimming mechanism operates in the course of raising the needle bar in the second cycle from the start of sewing.
After the needle bar is connected, thread cutting is surely performed.

[0013]

Embodiments of the present invention will be described below with reference to the drawings. The present embodiment includes three embroidery sewing machines. In each embroidery sewing machine, a multi-head embroidery sewing machine in which all the rotary hooks for capturing the thread wheel are driven to rotate by a hook drive motor independently of the sewing machine motor. This is a case where the present invention is applied. The multi-head embroidery sewing machine M will be described. As shown in FIG. 1, a substantially rectangular sewing support plate 2 having a predetermined length in the left-right direction is provided on the rear side of the upper surface of a base frame 1 extending in the left-right direction. A support frame 3 extending in the left-right direction is erected at the rear end portion of the sewing machine support plate 2.
In addition, the three heads 4 to 6 are arranged side by side at predetermined intervals in the left-right direction, and the base frame 1 located at the front end of the sewing machine support plate 2 is made to correspond to each of these heads 4 to 6. The rear ends of the cylindrical bed portions 7 to 9 formed in the bed units 10 to 12 are supported respectively.

That is, three multi-needle embroidery sewing machines M1 to M3 comprising head portions 4 to 6 provided on the support frame 3 and bed units 10 to 12 having independent structures are arranged side by side. At the front end of each of the heads 4 to 6 of these embroidery sewing machines M1 to M3, 12
The needle bar cases 20 that support the needle bars 21 so as to be vertically movable and the twelve balances 23 that are swingable are supported so as to be movable in the left-right direction. By a needle bar changing mechanism (not shown) driven by a motor 115 (see FIG. 8),
It is possible to change the thread color of embroidery sewing at the same time.

A work table 13 is horizontally arranged so that it is flush with the upper surfaces of the bed units 10 to 12 on the front side of the sewing machine support plate 2.
A movable frame 16 having a rectangular frame shape in a plan view and extending in the left-right direction is mounted on a pair of auxiliary tables 14 and 15 provided on both left and right sides of the work table 13 including the work table 3.

The drive frame portion 16a at the left end of the movable frame 16 is moved and driven in the X-axis direction (left-right direction) by an X-axis drive mechanism (not shown), and at the same time as the drive frame portion 16b at the right end thereof. This drive frame portion 16a is moved and driven in the Y-axis direction (front-back direction) by a Y-axis drive mechanism (not shown).
Therefore, the movable frame 16 includes an X-axis driving mechanism driven by an X-axis driving motor 117 (see FIG. 8) and a Y-axis driving motor 119.
(See FIG. 8) The Y-axis drive mechanism drives the XY
It can be moved on a plane. Also, auxiliary table 1
An operation panel 18 for executing various commands is provided on the rear side of the display 6a for displaying a message related to embroidery sewing.

Next, a needle bar up-and-down drive mechanism 25, which is provided for each embroidery sewing machine M1 to M3 and vertically drives the needle bar 21, will be described with reference to FIG. A base needle bar 26 extending in the vertical direction is provided at the tip of each of the head units 4 to 6, and the base needle bar 26 is supported by the frame F at the upper end and the lower end. A vertically moving member 27 having an engaging groove 27a that engages with a connecting pin 34, which will be described later, is vertically movably inserted into the base needle bar 26, and the needle bar is provided at the lower end of the vertically moving member 27. The body 28 is vertically movably and non-rotatably fitted into the base needle bar 26, and the body 28 is moved vertically.
An up-and-down moving member 27 is rotatably connected to the lower end of 7. The needle bar holder 28 has a link 31 connected to a swing lever 30 that is swingably supported by a pivot 29.
It is connected to.

On the other hand, an eccentric cam 32 is fixed to a sewing machine main shaft 17 which is inserted in the respective head portions 4 to 6 and arranged in the left-right direction, and the lower end of an eccentric lever 33 externally fitted to the eccentric cam 32. The part is connected to the swing lever 30. By the way, a sewing needle 22 is attached to the lower end of each of the twelve needle bars 21, and a connecting pin 34 is fixed to each of the intermediate pins in the height direction. A compression spring 35 is externally fitted to the support frame of the needle bar case 20, and the needle bar 21 is always elastically biased to the upper needle position by the compression spring 35.
Further, when the needle bar case 20 moves in the left-right direction, the connecting pin 34 of the needle bar 21 facing the vertical movement member 27 is selectively engaged with the engagement groove 27 a of the vertical movement member 27. Has become.

As a result, the sewing machine main shaft 17 is rotated by rotationally driving the sewing machine motor 110 in a predetermined rotation direction, and the up-and-down moving member 27 and the needle bar are held via the eccentric lever 33, the swing lever 30 and the link 31. As the and 28 move up and down integrally, only the needle bar 21 connected to the up-and-down moving member 27 via the connecting pin 34 is reciprocally driven up and down in synchronization with the main shaft 17. Next, each embroidery sewing machine M1 to M
The needle bar jump mechanism 40 that is provided for every 3 and that causes the needle bar 21 to jump to its uppermost position (top dead center position),
A description will be given based on FIG. In the needle bar case 20, a horizontally oriented needle bar jump solenoid 41 is provided, and a rotary lever 42 having a substantially L shape in plan view is attached to the needle bar case 20 so as to be rotatable around a vertical axis. There is. Then, the drive portion 42a of the rotation lever 42 contacts the plunger of the needle bar jump solenoid 41, and
The operation shaft 43 attached to the driven portion 42b and oriented vertically
Is a projecting engagement portion 2 integrally formed with the vertical movement member 27.
7a can be engaged.

Further, the vertically moving member 27 is always elastically moved by a winding spring 44 provided at the upper end thereof so as to rotate from a rotated jump position indicated by a two-dot chain line to a normal connection position indicated by a solid line. It is being rushed. As a result, when the needle bar 21 is connected to the vertical movement member 27 via the connecting pin 34, the needle bar jump solenoid 41 is driven for a predetermined time, and when the plunger advances to the right, The rotation lever 42 rotates clockwise in a plan view, and the vertical movement member 27 rotates to the jump position indicated by the chain double-dashed line via the operation shaft 43 and the engaging portion 27a, and is connected. The engagement between the pin 34 and the engagement groove 27a is released, and at the same time, the needle bar 21 is moved (jump operation) to the needle up position at once by the compression spring 35.

On the other hand, when the needle bar 21 has jumped to the needle upper position and the vertical moving member 27 has returned to the connecting position, the vertical moving member 27 rises from below to the direction of its substantially uppermost position. Sometimes, the vertical moving member 27 is
4 is contacted from below and is temporarily rotated to the jump position, but is immediately rotated back to the connecting position by the winding spring 44, and the connecting pin 34 is automatically connected to the engaging groove 27a. ing. Here, the presser foot 45 provided on each of the bed portions 7 to 9 is a presser foot that presses the work cloth W on the bed portions 7 to 9 by a presser foot drive mechanism (not shown) driven by the presser foot drive solenoid 106. The position can be switched up and down between the position and the retracted position which has been raised by a predetermined distance.

Next, the bed units 10 to 12 will be described with reference to FIGS. Here, since the three bed units 10 to 12 have the same configuration, the leftmost bed unit 10 will be described. A bed case 50 having a substantially U-shaped cross section extending in the front-rear direction has a pair of support brackets 5 fixed to a base frame 1 extending in the left-right direction at the front end of the sewing machine support plate 2 at its rear end.
1, and a hook module 55 is detachably fixed to the front end portion of the bed case 50. here,
The upper side of the bed case 50 is covered with a throat plate 52 at its front end portion and a cover plate 53 continuous with the throat plate 52.

Next, the shuttle module 55 will be described. As shown in FIGS. 4 to 5, a mounting block 56 is detachably fixed to the front end portion of the bed case 50 with a screw 57, and a shuttle drive motor including a pulse motor is attached to the rear end side of the mounting block 56. 58 is attached. On the other hand, on the front end side of the attachment block 56, a full rotary hook 59 for catching the yarn wheel is provided, and the hook shaft 60 fixed to the full rotary hook 59 is pivotally mounted on the attachment block 56 so that the position thereof can be adjusted in the front-rear direction. It is supported. The first connecting member 62 attached to the rear end of the shuttle shaft 60 and the second connecting member 63 attached to the front end of the drive shaft 58a of the shuttle drive motor 58 are connected to each other. That is, the shuttle shaft 60 and the drive shaft 58a are connected by the coupling 61 including both connecting members 62 and 63.

Here, the full rotary hook 59 will be briefly described. As shown in FIG. 21, an inner hook holding a bobbin case 67 for accommodating a bobbin and an outer hook 59a rotating outside the inner hook. And the outer thread 59a has the upper thread 4
Sword tip 5 for hooking 7 to form the upper thread loop 47c
9b is formed. And, the spindle 18 is about "200
"", The sword tip 59b and the eye of the sewing needle 22 come into contact with each other (see FIG. 19), and the sword tip 59b moves the needle side upper thread 47a extending from the eye of the sewing needle 22 at this encounter timing. The upper thread loop 47c that moves between the inner hook and the outer hook 59a is formed by hooking and rotating the outer hook 59a.

Further, a disk encoder 64 is attached to the second connecting member 63, and a plurality of slits formed in the disk encoder 64 are optically detected, and a photo sensor which outputs a shuttle shaft rotation signal is provided. The second
The encoder sensor 65 is attached to the attachment block 56. Then, by driving the shuttle drive motor 58, the shuttle shaft 60 is rotationally driven via the drive shaft 58a and the coupling 61, and the full rotary shuttle 59 is doubled in the predetermined rotation direction with respect to the sewing machine main spindle 17. It is driven to rotate at a rotation speed K. Here, the front end portion of the bed unit 10 is covered with a protective cover 66 that is pivotally supported at the lower end of the front end portion of the bed case 50 so as to be openable and closable via a hinge mechanism.

Here, a brief description will be given of a pivot structure for pivotally supporting the rotary hook 59 so as to adjust the position in the front-rear direction. Immediately inside the cylindrical portion of the mounting block 56, a cylindrical bearing case 70 is provided so as to be slidable in the front-rear direction, and a bearing 71 is pressed into the bearing case 70. An eccentric pin 72 is mounted on the left side wall of the mounting block 56,
The pin portion at the tip of the eccentric pin 72 is the bearing case 7
0 is engaged with a vertically long pin hole formed on the left side wall,
On the other hand, a set screw 73 to which the bearing case 70 can be fixed is detachably provided on the right side wall of the mounting block 56.

That is, by loosening the set screw 73 and rotating the eccentric pin 72 clockwise or counterclockwise, the bearing case 70 is moved forward or backward through the pin hole by a small distance (for example, 1 to 3). 2 mm), the position of the rotary hook 59 can be finely adjusted in the front-rear direction at the same time, and the needle gap can be adjusted.

Next, a thread cutting mechanism 80 provided in each of the bed units 10 to 12 for cutting the upper thread 47 and the lower thread 48.
Will be described with reference to FIGS. 3 to 6. A fixed plate (not shown) fixed to the mounting block 56 extends to the upper side of the entire rotary hook 59, and the movable plate 81 has a standby position shown by a solid line and a maximum rotation position shown by a two-dot chain line on the fixed plate. It is pivotally supported so that it can swing. The fixed blade 8 for cutting the upper thread 47 and the lower thread 48 in cooperation with the movable blade 81.
2 is attached to the lower side of the needle plate 52 immediately above the fixed plate with the blade portion facing forward.

The thread-cutting operating lever 83 connected to the movable blade 81 extends through the bed case 50 rearward. That is, the movable blade 81 is rotated clockwise by the forward movement of the thread trimming operation lever 83, and
In the middle of the backward movement of the movable blade 81 in the counterclockwise direction by the backward movement of the thread trimming operation lever 83 after the forward movement to the maximum rotation position indicated by the two-dot chain line in FIG. Are engaged with the engaging portion 81a of the movable blade 81, and thereafter, the upper thread 47 and the lower thread 48 are simultaneously cut by the cooperation of the movable blade 81 and the fixed blade 82.

Next, a thread trimming drive mechanism 85 for driving the thread trimming mechanism 80 will be described with reference to FIGS. 3 and 7. A rear end portion of the thread trimming operation lever 83 is horizontally attached to the rear end portion of the bed case 50 so as to be horizontally rotatable.
It is connected to the driven portion 86 a of the character-shaped rotating plate 86. On the other hand, at the left end of the base frame 1, the base frame 1
A thread trimming motor 88 is attached to a mounting plate 87 fixed to the lower side from below, and a fan-shaped swinging member 90 meshing with a drive gear 89 of the thread trimming motor 88 is rotated to the mounting plate 87 by a stepped bolt 91. It is movably pivoted. Furthermore,
A base end portion of a plate-shaped connecting plate 92 is attached to the swing member 90, and a left end portion of a thread trimming operation shaft 93 extending in the left-right direction is connected to a tip end portion of the connecting plate 92.

A drive portion 86b of the rotating plate 86 is connected to the thread cutting operation shaft 93. This allows
Rotation of the thread cutting motor 88 in the counterclockwise direction causes the swing member 90 to rotate clockwise by a predetermined angle, and the thread cutting operation shaft 93 moves rightward by a predetermined distance via the connecting plate 92. As a result, the rotating plate 86 is rotated in the clockwise direction and the thread trimming operating lever 83 is moved forward to move the movable blade 8
1 moves forward to the maximum rotation position. After that, the rotation of the thread cutting motor 88 in the clockwise direction causes the rotary plate 86 to rotate in the counterclockwise direction through the movement of the thread cutting operation shaft 93 to the left, and the thread cutting operation lever 83 moves backward. And the upper thread 47 and the lower thread 4 are engaged with the movable blade 81 as described above.
8 is simultaneously cut by the movable blade 81 and the fixed blade 82.

By the way, a moving position detecting sensor 94 consisting of a photo sensor is attached to the mounting plate 87 near the swinging member 90, and the swinging member 90 detects the moving position detecting sensor 94. A shield plate 95 is attached. That is, since the moving position detection sensor 94 does not detect the shielding plate 95 when the movable blade 81 is moving within the moving range from the cutting position to the maximum rotation position, the moving position detection of the “L” level is performed. While the signal DS is output, when the movable blade 81 moves to the cutting position in the backward movement direction, the shield plate 95 is detected and the “H” level moving position detection signal DS is output.

Next, the outline of the control system of the multi-head embroidery sewing machine M will be described with reference to the block diagram of FIG. A sewing machine control device 100 that controls the entire embroidery sewing machine M other than the hook drive control includes a CPU 101, a ROM 102, and a RAM.
And an input interface (not shown) and an output interface (not shown) connected to the microcomputer via a bus such as a data bus.

With respect to the head section 4, a drive circuit 105 for the needle bar jump solenoid 41, a drive circuit 107 for the presser foot drive solenoid 106, and a thread break sensor 108 are connected to the sewing machine controller 100. The other head portions 5 and 6 are similarly connected. Further, the sewing machine control device 100 includes a drive circuit 111 that drives the sewing machine motor 110, a first encoder sensor 112 that outputs 1000 slit signals per revolution of a disk encoder provided in the sewing machine motor 110, and a first encoder sensor 112 that outputs the slit signal. A spindle origin sensor 113 that outputs one spindle origin signal by one rotation of one encoder sensor 112, and a stop position sensor 114 that detects a stop position of the needle bar 21 (a rotation position of the sewing machine spindle 17 of about 100 °). Needle bar changing motor 1 for changing needle bar 21 driven by moving needle bar case 20
15, a drive circuit 116 for the X-axis drive motor 117, a drive circuit 120 for the Y-axis drive motor 119, and a plurality of switches for instructing sewing start and various commands. Display 1 provided
The operation panels 18 provided with 8a are respectively connected.

On the other hand, it is connected to the sewing machine controller 100,
The hook shaft control device 150, which controls the drive control and the thread cutting control of the full rotary hook 59, includes a CPU 151, a ROM 152, and a RAM 1.
53, and an input interface (not shown) and an output interface (not shown) connected to the microcomputer via a bus such as a data bus. With respect to the bed unit 10, a drive circuit 154 for the shuttle drive motor 58, a second encoder sensor 65 for outputting 50 slit signals by one rotation of the disk encoder 64, and this disk are provided in the shuttle shaft control device 150. The hook shaft origin sensor 155, which outputs one hook shaft synchronizing signal by one rotation of the encoder 64, is connected to each of the other bed units 11 and 12.
Are similarly connected. Further, a moving position detection sensor 94 and a drive circuit 156 for the thread cutting motor 88 are connected to the shuttle shaft control device 150, respectively.

Here, the sewing machine motor 110 is composed of an induction motor and is inverter-controlled. The 1000 spindle rotation signals (slit signals) output from the first encoder sensor 112 in one rotation of the disk encoder provided in the sewing machine motor 110 are 40
The pulse is subdivided into 00 pulses and used as a spindle control pulse in drive control of the motor. On the other hand, the shuttle drive motor 58 is
It consists of a stepping motor, which receives 500 pulses and becomes 1
At the same time, the full rotary hook 59 also makes one revolution. Then, the shuttle drive motor 58 moves 2 times during one revolution of the sewing machine main shaft 17.
Double speed (hereinafter, referred to as shuttle shaft rotation speed K) drive control is performed so as to rotate.

Next, a hook shaft drive control routine executed by the hook shaft controller 150 will be described with reference to the flowcharts of FIGS. 9 to 15. However, reference numeral Si (i
= 10, 11, 12, ...) is each step. Here, the signal output from the sewing machine control device 100 to the shuttle shaft control device 150 will be briefly described with reference to FIG. 18. At the start of sewing, the sewing machine main shaft 17 normally stops at a rotational position of about “100 °”. And needle bar 21
Is stopped by jumping to its uppermost position by the needle bar jump mechanism 40.

When the embroidery data having the needle drop data for N stitches is to be sewn, the main shaft drive signal from the sewing machine control device 100 is switched to the "H" level, and at the same time, the driving of the sewing machine motor 110 is started. It here,
This embroidery data does not include thread trimming data for thread replacement, and thread trimming is performed at the second stitch and the last N stitches at which N stitches of embroidery sewing have been performed.

In FIG. 19, the needle bar movement locus, the balance movement locus, the hook thread amount, and the rotary position of the full rotary hook 59 during sewing are made to correspond to the rotary position of the main shaft 17, respectively. Show. However, the rotation position of the full rotary hook 59 is indicated by the rotation position (rotation angle) of the sword tip 59a. By the way, the needle bar 21 is "0 °" of the sewing machine main shaft 17 at the first stitch.
When, that is, when the needle bar 21 is at the uppermost position, the needle bar 21 is automatically connected to the up-and-down moving member 27. Therefore, when the pulling-in operation (picker operation) or the thread cutting operation of the upper thread 47 at the start of sewing is not performed, A stitch is formed from the second stitch onward. Then, at the final stitch of the Nth stitch, when the sewing machine spindle 17 is at about "260 °", the spindle drive signal is switched to the "L" level, the thread trimming signal is output, and then "270" of the sewing machine spindle 17 is output. "~ 440 ° (88 °)", the thread trimming operation is executed and immediately after that, the sewing machine spindle 1
7 "460 ° (100 °)", sewing machine spindle 1
The rotation of 7 is actually stopped.

When the multi-head type embroidery sewing machine M is powered on, this control is started, and first, the spindle / hook axis initial setting process (see FIG. 10) is executed (S10). When this control is started, first, the stop position signal from the stop position sensor 114 is read, and when the main spindle 17 is in the stop position, that is, when the thread is cut after the last sewing process is completed, the normal "100 °" is set. At the initial setting position, and at the stop position (S25: Yes), the rotary position of the hook shaft 60 is the rotation position of the main shaft 17 by about 13 °, the hook shaft synchronization signal is the hook shaft origin sensor 155. In order to return to the rotational position at the time of output from the shuttle, the shuttle drive motor 58 is reversely driven by one pulse (S26), and when the shuttle shaft origin sensor 155 does not output the shuttle shaft synchronization signal (S27: No), S26. ~ S27
20 is repeated, the hook shaft 60 moves to the initial setting position "18", which is the rotation start position of the main shaft 17, as shown in FIG.
When it is rotated to the initial setting position corresponding to “0 °” (S
27: Yes), end this control, and execute S11 of the hook shaft drive control.
Return to

By the way, when the main spindle 17 is not in the stop position (S25: No), the sewing machine controller 100 displays an error message to that effect on the display 18a. Therefore, the operator manually rotates the sewing machine main spindle 17. Set the stop position. Next, in the hook shaft drive control, when the “H” level main shaft drive signal is not output from the sewing machine controller 100, that is, when sewing is not started (S11: No), this S11 is repeated until sewing is started. Be waited for. Then, when the sewing machine control device 100 outputs a spindle drive signal of "H" level at the start of sewing (see FIG. 18) (S11: Yes), the sewing machine motor 110 is driven to rotate at the same time, and the spindle 17 rotates to the rotational position ". It is driven from 100 °.

Then, as shown in FIG. 20, at the first stitch after the start of sewing, when the spindle 17 rotates to about "170 °" and the spindle origin sensor 113 outputs a spindle synchronizing signal (S12: Yes), and when thread cutting is performed in response to a command from the sewing machine controller 100 (S13: Yes), upper thread remaining amount securing processing control (see FIG. 11) at the start of sewing is executed during thread cutting operation (S14). . Here, at substantially the same time as this upper thread remaining amount securing processing control, “270 °” of the main spindle 17 is performed.
The yarn cutting process is executed from the rotation position of 1., but this yarn cutting process will be described later.

When the upper thread remaining amount securing process control for securing the upper thread remaining amount ahead of the eye of the sewing needle 22 is started, as shown in FIG. 20, the main spindle 17 is moved during the sewing operation of the second stitch. Until the rotary position of "300 °" is reached, the shuttle shaft synchronous drive processing control (see Fig. 12) is executed while rotating the shuttle shaft 60 at the predetermined rotation speed K (S30). When this control is started, the rotation position of the spindle 17 is read by constantly counting the spindle rotation signal output from the first encoder sensor 112 (S50), and in order to synchronize with the rotation of the spindle 17, When it is time to drive the shuttle shaft 60 by one step (S51: Yes), the shuttle drive motor 58 is set to 1
Rotational drive is performed by the number of steps (S52).

Next, in order to confirm the rotation of the shuttle shaft 60,
The count value I of the counter that counts the number of drive steps of the shuttle drive motor 58 is incremented by 1 (S5
3) When the shuttle shaft rotation signal from the second encoder sensor 65 does not change (S54: No), when the count value I is less than or equal to the predetermined count value P (for example, 10 to 15) (S54: No).
55: Yes), this control is terminated, and the process returns to S31 of the upper thread remaining amount securing process control. On the other hand, when the shuttle shaft rotation signal changes (S54: Yes), the count value I is cleared (S65) because the shuttle shaft 60 is reliably driven.
Similarly, the process returns to S31.

By the way, when it is not time to drive the shuttle shaft 60 (S51: No), and when the shuttle shaft synchronization signal is not input from the shuttle shaft origin sensor 155 (S57: No), the routine similarly returns. However, when the shuttle shaft synchronizing signal is input (S57: Yes), the data of the synchronous drive position table in which the allowable number of drive pulses of the shuttle drive motor 58 corresponding to the rotational position of the spindle 17 is tabulated is stored in the ROM 152 in advance. Since it is stored, the shuttle shaft 60 is allowed to synchronize with the main spindle 17 based on the rotational position of the main spindle 17 read in S50, the number of drive pulses of the shuttle drive motor 58, and the data of the synchronous drive position table. When the synchronous drive is performed within the range (S58: Yes), the process similarly returns to S31.

Here, the count value I is the predetermined count value P.
Is larger than the above (S55: No), or when the shuttle shaft 60 exceeds the allowable synchronous range for the main shaft 17, that is, is not driven synchronously (S58: No), the abnormality processing control (FIG. 1).
5) is executed (S59). When this control is started, the needle bar jump solenoid 41 is driven for a predetermined time (S90). As a result, as described above, the vertical movement member 27 rotates to the jump position, and the needle bar 21 jumps to the needle up position at once. Accordingly, it is possible to prevent the sewing needle 22 from colliding with the full rotary hook 59.

Next, a spindle drive stop command is output to the sewing machine control device 100 to stop the driving of the sewing machine motor 110 (S91). As a result, the sewing machine control device 100 outputs a brake operation signal to the drive circuit 111, and the sewing machine motor 110 is immediately stopped. At the same time, a drive stop process for outputting a brake actuation signal is similarly executed for the drive circuit 154 (S92), and the shuttle drive motor 58 is immediately stopped. Next, a display command for displaying an error message indicating that the machine has stopped abnormally on the display 18a is output to the sewing machine control device 100 (S93).

When the operator releases the abnormal state and the error state is released by operating the error release switch of the operation panel 18 (S94: Yes).
), And ends this control, and returns to S10 of the hook shaft drive control. Next, in the needle thread remaining amount ensuring process control, when the spindle 17 reaches "300 °" while the needle bar 21 of the second needle (corresponding to the second cycle) is being raised (S31:
Yes), the drive of the shuttle drive motor 58 is temporarily stopped until the main shaft 17 reaches "335 °", and the rotation of the shuttle shaft 60 is forcibly stopped temporarily (S32: No).

In other words, during the sewing of the second stitch, the spindle 1
When 7 is "300 ° to 335 °", the full rotary hook 59
20 to 21 are the rotational positions shown in FIGS. 20 to 21 when the upper thread loop 47c is formed at its maximum and cannot be removed from the full rotary hook 59. Is the rising period. At this time, regarding the embroidery sewing machines M1 to M3 in which the thread breakage did not occur,
The upper thread 47a extending from the eyelet of the sewing needle 22 is continuous with the work cloth W, and the embroidery sewing machines M1 to M3 in which thread breakage has occurred are threaded, and the thread end of the threaded upper thread is, for example, It is in a state of being hooked on the needle bar case 20 or held by the operator. During this period, the rotation of the full rotary hook 59 is temporarily stopped. It will be paid out from a thread spool not shown.

As a result, when the thread is cut by the thread cutting operation described later, a sufficient upper thread remaining amount for preventing the upper thread end from slipping out of the eye hole at the start of the next sewing operation is provided. It is ensured corresponding to the amount of yarn delivered from the. Then, when the spindle 17 reaches "335 °" (S32:
Yes), and through S33 to S46, the shuttle drive motor 58 is rotated by the main spindle 1 during the rotation period in which the main spindle 17 rotates by about "38 °".
In order to have a high rotation speed proportional to the rotation speed of 7,
Moreover, by controlling the drive so as not to exceed the self-starting frequency and quickly removing the needle thread loop 47c from the full rotary hook 59,
The upper thread remaining amount is stabilized.

That is, from the time when the spindle 17 reaches "335 °", the shuttle drive motor 58 is rotationally driven at the predetermined rotational speed K for the first 10 pulses (S33 to S34: Yes).
), The drive pulse cycle is set so that K = 1.5 (S35), and the shuttle drive motor 58 is rotationally driven at the rotational speed of 1.5 K for the next 10 pulses (S36 to S37: Ye).
s), the drive pulse cycle is then set to K = 2 (S38), and the shuttle drive motor 58 is rotationally driven at the rotational speed 2K for the next 141 pulses (S39 to S40: Ye).
s).

Then, the drive pulse cycle is set so that K = 1.5 (S41), and the shuttle drive motor 58 is rotationally driven at the rotational speed of 1.5 K for the next 10 pulses (S42).
~ S43: Yes), the drive pulse cycle is set so that K = 1 (S44), and the shuttle drive motor 58 is rotationally driven at the rotational speed K for the next 10 pulses (S45-S).
46: Yes). Finally, the process waits until "185 °", which is the rotational position of the main shaft 17 corresponding to the rotational position of the full rotary hook 59 when rotated by 10 pulses in S46 (S47:
No), when the spindle 17 reaches the rotational position of "185 °" (S47: Yes), this control is terminated, the process returns to S15 of the hook shaft drive control, and the actual sewing is started.

Next, the thread cutting processing control which is executed at the same time as this upper thread remaining amount securing processing will be described with reference to FIGS. By the way, this cutting processing control is included in the thread cutting control which is executed in parallel with the above-mentioned shuttle shaft drive control when the power is turned on. First, the thread cutting control will be described.

When the multi-head embroidery sewing machine M is powered on, this control is started, and first, the initial setting of the movable blade 81 is executed by S100 to S108. That is, the moving position detection signal DS from the moving position detection sensor 94 is "H".
At the level, that is, by detecting the shield plate 95, the movable blade 81 is detected.
At the cutting position (S100: Yes), "1" indicating the forward direction is set as the flag data of the driving direction flag DF of the thread cutting motor 88 (S101), and the moving position detection signal DS is "L". The thread cutting motor 88 is driven one pulse at a time until the level reaches the level, that is, until the movable blade 81 is rotated in the forward direction by a predetermined amount from the cutting position (S10).
2, S103).

When the moving position detection signal DS becomes "L" level (S103: No), the thread trimming motor 8
8 is driven by an additional 5 pulses, and the movable blade 81 is further rotated in the forward direction by a minute predetermined amount (S104). Next, "0" indicating the backward direction is set as the flag data of the driving direction flag DF of the thread trimming motor 88 (S105), and the moving position detection signal DS becomes "H" level, that is, the movable blade. The thread trimming motor 88 is driven one pulse at a time until 81 returns to the cutting position (S10).
6, S107). Then, the moving position detection signal DS is "H".
When the level is reached (S107: Yes), the thread cutting motor 88 is further driven by an additional 5 pulses, and the movable blade 81 is further rotated in the backward direction by a small predetermined amount (S10).
8).

Then, from the sewing machine controller 100, "H"
When a level spindle drive signal is received (S109: Yes
), S109 and S110 are repeated until the thread trimming signal is received from the sewing machine controller 100, and the process waits. And 2
In the sewing operation of the stitches, when the main shaft 17 is at the rotational position of about "260 °" and the thread trimming signal is received (see FIG. 18) (S110: Yes), the cutting process control (see FIG. 17) is performed. It is executed (S111). This control is started,
When the spindle 17 reaches the rotational position of "270 °" (S
120: Yes), and the drive direction flag DF is set (S12
1), as shown in Fig. 22, set the spindle control pulse to "11".
Driving the thread trimming motor 88 for one pulse by counting the pulse amount is repeated for 20 pulses (S122 to S123).

When the thread trimming motor 88 is driven by 20 pulses (S123: Yes), the spindle control pulse is counted by "4" pulses, and the thread trimming motor 88 is driven by 1 pulse only for 27 pulses. It is repeatedly executed (S124 to S125). Further, set the thread trimming motor 88 to 2
When driven by 7 pulses (S125: Yes), the spindle control pulse is counted by "2" pulses and the thread trimming motor 8
Driving 8 for one pulse is repeated for 121 pulses (S126 to S127). That is, this final one
When driving 21 pulses, the outer pot 5 of the full rotary pot 59
The upper thread 47a from the sewing needle 22 and the lower thread 4 which are separated by separating the upper thread 47 from a bifurcated thread guide section 59c (see FIG. 21) formed in a portion of the outer peripheral portion of 9a facing the sword tip 59b.
8 and the upper thread 47b on the work cloth side are separated by the movable blade 81.

Then, when the thread cutting motor 88 is driven by 121 pulses, as shown in FIG.
1 is a state in which the lower thread 48 and the upper thread 47b on the work cloth side can be engaged with each other and moved forward to the maximum rotation position. Here, in FIG. 23, for convenience of explanation, the upper thread (needle thread) from the sewing needle 22 in the horizontal plane where the movable blade 81 is located.
47a, an upper thread 47b connected to the work cloth W, and a lower thread 48.

Next, in this state, the thread trimming motor 88 reaches the "335 °" rotational position of the main spindle 17, which is the timing for rotating the shuttle shaft 60 at a high rotational speed proportional to the rotational speed of the main spindle 17. When the drive is stopped (S128: No) and the spindle 17 reaches the rotational position of "335 °" (S128: No).
128: Yes), the drive direction flag DF is reset to move the movable blade 81 back (S129), the spindle control pulse is counted by "3" pulses, and the thread trimming motor 88 is driven by one pulse. The process is repeated by the number of pulses (S130 to S131). At this time, the lower thread 48 and the work cloth side upper thread 47 b are engaged with the engaging portion 81 a of the movable blade 81.

Further, when the thread trimming motor 88 is driven by 100 pulses (S131: Yes), the spindle control pulse is counted by "14" pulses, and the thread trimming motor 88 is driven by one pulse. It is repeatedly executed until DS becomes "H" level (S132 to S133).
). Here, in the final part of the driving period for 100 pulses of the thread cutting motor 88, the upper thread 47 and the lower thread 47 are cooperated with each other by the movable blade 81 and the fixed blade 82 at the timing shown by the one-dot chain line in FIG. 48 and 48 are disconnected at the same time. Furthermore,
The thread cutting motor 88 is further driven by an additional 5 pulses, and the movable blade 81 is further rotated in the backward direction by a small predetermined amount (S134 to S135).

When the movable blade 81 is additionally rotated by 5 pulses (S135: Yes), it means that the movable blade 81 has been initialized, and this control is terminated and the process returns to S109 of the thread trimming control. As described above, the input waiting of the next thread trimming signal is executed. At this time, as shown in FIG. 24, the movable blade 81 is in the state of moving forward to the original standby position, and the cut end of the bobbin thread 48 is not shown in the figure provided below the fixed blade 82. It is held by the thread holder.

That is, as shown in FIGS. 20 and 22, the thread cutting timing is when the full rotary hook 59 is rotationally driven at a high speed proportional to the rotational speed of the main spindle 17 and the main spindle 17 is at a substantially predetermined rotational position. In addition, by quickly removing the upper thread loop 47c from the full rotary hook 59, the variation in the timing at which the upper thread loop 47c comes off the full rotary hook 59 is reduced, and the upper thread remaining amount secured after cutting is stabilized. You can Further, the remaining amount of the upper thread secured at this time is sufficient and an optimum amount of thread to prevent the upper thread end from coming off from the eye hole of the sewing needle 22 at the start of the next sewing operation. There is.

Here, since the upper thread 47 extending from the eyelet of the sewing needle 22 is not broken at the start of sewing, the work cloth W
If it is continuous, or by threading after thread breakage,
Even if the needle thread remaining from the eyelet to the needle thread end is long, the needle bar 2
At the second needle 1 in which the vertical movement has started via the needle bar jump mechanism 40, the upper thread 47 extending from the eye hole is cut below the needle plate 52, and the upper thread remaining amount ahead of the eye hole is a predetermined amount. Since the upper thread end is not entangled in the full rotary hook 59 or sewn on the back side of the work cloth W after the next third stitch sewing operation, the smoothing of the sewing process at the start of sewing is performed. And the formation of beautiful seams can be ensured.

Then, in the hook shaft drive control, the sewing processing control (see FIG. 13) is executed (S15). When this control is started, the spindle drive signal from the sewing machine control device 100 is at the “H” level, and during sewing (S65: Ye
s) From the 3rd stitch to the last N stitch sewing operation,
That is, as described above, the hook shaft synchronous drive process control is repeatedly executed until the main shaft drive signal becomes the “L” level and the sewing process is completed, and the sewing operation is sequentially performed for each stitch ( S66). When the final Nth stitch is sewn and the spindle drive signal of "L" level is input (S65: No), this control is terminated and the process returns to S16 of the hook shaft drive control.

In the hook shaft drive control, when thread cutting is not executed by a command from the sewing machine controller 100 at the last stitch (S16: No), the spindle 17 is set to "36".
The hook shaft synchronous drive processing control is executed until it becomes 0 ° (S
18, S19: No), when the main shaft 17 reaches the rotational position of "360 °" so that the sword tip 59b does not collide with the sewing needle 22 (S19: Yes), the process returns to S10. On the other hand, when the thread cutting is executed (S16: Yes), the upper thread remaining amount ensuring process control (see FIG. 14) at the end of sewing is executed (S17). here,
At the same time as this upper thread remaining amount securing processing control at the end of sewing, the spindle 1
As described above, the yarn cutting process is executed from the rotational position of “270 °” of No. 7.

Next, when the remaining amount securing processing control for securing the remaining amount of the upper thread ahead of the eye of the sewing needle 22 is started, as shown in FIG. 25, during the sewing operation of the final Nth stitch, Until the main shaft 17 reaches the rotation position of "300 °", the hook shaft 6
0 is synchronously driven at a predetermined rotation speed K (S70, S71:
No). When the main spindle 17 reaches "300 °", the full rotary hook 59 is at the rotational position shown in FIGS. 21 and 25, and the rotary hook drive motor 58 is temporarily driven until the main spindle 17 reaches "335 °". Then, S72 to S86 are controlled in the same manner as S32 to S46 described above.

That is, when the Nth stitch is being sewn, the spindle 1
When 7 is "300 ° to 335 °", the needle thread loop 4
7c is formed at its maximum and cannot be disengaged from the full rotary hook 59, and while the cloth feed is being executed, the sewing needle 2
2 and the balance 23 is in a rising period. At this time, the upper thread 47a extending from the eyelet of the sewing needle 22 is connected to the work cloth W, and the rotation of the entire rotary hook 59 is temporarily stopped during this period, so that the sewing needle 22 and the balance 23 are raised. The deficient amount of yarn will be fed from a yarn spool not shown. Then, by the thread trimming operation which is executed at the same time as this upper thread remaining amount securing process control, there is sufficient upper thread remaining amount for preventing the upper thread end portion from coming off from the eyelet hole at the start of the next sewing operation. , It is ensured in correspondence with the amount of yarn delivered from the thread spool.

In the above multi-head embroidery sewing machine M, the operation of thread cutting operation at the start of sewing will be described. At the start of sewing to embroider N stitches of embroidery data, the hook drive motor 58 is temporarily driven until the main spindle 17 reaches from "300 °" to "335 °" while the second needle bar 21 is being raised. Then, the rotation of the shuttle shaft 60 is forcibly stopped temporarily, and the shortage of the thread amount corresponding to the elevation of the sewing needle 22 and the balance 23 is fed out from the thread spool, and the thread cutting mechanism 8
The upper thread 47 is cut by 0.

That is, when the upper thread 47 extending from the eyelet of the sewing needle 22 is not thread-cut at the start of this sewing and is continuous with the work cloth W, or by threading after thread-cutting, the needle thread 47 is raised from the eyelet Even if the upper thread remaining amount up to the thread end is long, the upper thread 47 extending from the eyelet is cut at the lower side of the needle plate 52 and the upper thread remaining amount from the eyelet is set to a predetermined amount. After the next sewing operation of the third stitch, the upper thread end does not come out of the eye hole of the sewing needle 22, and the upper thread end may be entangled with the full-rotary hook 59 or sewn on the back side of the work cloth W. Therefore, the smoothing of the sewing process at the start of sewing and the formation of beautiful seams can be ensured.

In this way, when the upper thread 47 extending from the eyelet of the sewing needle 22 is connected to the work cloth W at the start of sewing,
Alternatively, even if the upper thread remaining amount from the eyelet to the upper thread end is long due to threading after thread breakage, the upper thread extending from the eyelet has an appropriate length after the predetermined amount of upper thread is fed. Since the cutting is performed so that the remaining amount is reached, the upper thread end after cutting is entangled with the lace portion of the full rotary hook 59 after the next sewing operation,
Since the work cloth W is not sewn on the back side of the work cloth W, the sewing process can be facilitated at the start of sewing and a clean stitch can be reliably formed.

Further, by the thread cutting at the second stitch,
Since the threaded upper thread end is cut at the lower side of the needle plate 52, the upper thread end easily comes off the work cloth W. Therefore, the end of the upper thread end protruding to the upper side of the sewn work cloth is eliminated. The work can be omitted. In addition, since a thread trimming drive mechanism 85 having a thread trimming motor 88 independent of the sewing machine motor 110 is provided and the thread trimming mechanism 80 is driven by this thread trimming motor 88, when the main spindle 17, the sewing needle 22 and the balance 23 are driven. Since the thread cutting load due to the thread cutting operation does not act on the sewing machine motor 110, the sewing machine motor 110 can be downsized.

The thread-cutting mechanism 80 is configured to perform a thread-cutting operation in conjunction with the main shaft 17 or the shuttle shaft 60, or a full-rotary shuttle 59 is provided by a shuttle drive mechanism which is rotationally driven by the driving force of the sewing machine motor 110. Various modifications may be made to the above-described embodiment based on existing technology or technology obvious to those skilled in the art, such as being configured to be driven. Further, it is needless to say that the present invention can be applied to various sewing machines such as a single-head type embroidery sewing machine having one embroidery sewing machine. Further, it is possible to adapt a stepping motor to the sewing machine motor 110, an AC servo motor to the shuttle drive motor 58, and various types of motors can be adopted as necessary.

[0073]

According to the sewing machine of claim 1, a sewing needle and
A sewing machine equipped with a thread catcher, a hook drive mechanism, and a thread trimming mechanism is provided with a drive means and a control means for controlling the drive means so that the thread trimming operation is performed at the start of sewing. Even if the needle thread extending from the eyelet of the sewing needle is continuous with the work cloth, or if the needle thread remaining amount from the eyelet to the needle thread end is long, the thread trimming mechanism ensures that the needle thread extending from the eyelet is appropriate. Since it is cut so that the remaining amount of upper thread of a certain length is obtained,
After the next sewing operation, the upper thread end after cutting does not get entangled in the loop for catching the thread loop and is not sewn on the back side of the work cloth, so the sewing process is smooth at the start of sewing and the beautiful stitches are obtained. The formation can be ensured.

In the sewing machine according to the second aspect, a sewing machine having a sewing needle and a balance, a thread catching hook, a hook drive motor, and a thread cutting mechanism is provided with a driving means and a thread cutting operation at the start of sewing. Since the control means for controlling the drive means is provided in the above, the same effect as that of claim 1 can be obtained. The sewing machine according to claim 3 has the same effect as that of claim 1 or 2, but since the drive means drives the thread trimming mechanism by an actuator independent of the sewing machine motor, the main shaft, the sewing needle and the balance are driven. At the same time, since the thread trimming load associated with the thread trimming operation does not act on the sewing machine motor, the sewing machine motor can be downsized.

In the sewing machine of the fourth aspect, the same effect as that of the third aspect can be obtained, but when the needle bar jump mechanism is provided and the needle bar is jumped to the uppermost position at the end of the sewing process. However, after the needle bar is connected to the needle bar drive mechanism in the second cycle from the start of sewing, by the control means,
Since the drive means is controlled so that the thread cutting mechanism operates the thread cutting mechanism during the lowering of the needle bar in the second cycle from the start of sewing, the thread cutting is surely executed after the needle bar is connected.

[Brief description of drawings]

FIG. 1 is a perspective view of a multi-head embroidery sewing machine.

FIG. 2 is a schematic perspective view of a needle bar vertical movement mechanism including a needle bar jump mechanism.

FIG. 3 is a plan view of a main part showing a work table and a bed unit.

FIG. 4 is a partial plan view of a bed unit provided with a hook module.

FIG. 5 is a partial vertical sectional side view of a bed unit provided with a shuttle module.

FIG. 6 is a partially enlarged plan view of a distal end portion of the bed unit.

FIG. 7 is an enlarged plan view of a thread cutting drive mechanism.

FIG. 8 is a block diagram of a control system of the multi-head embroidery sewing machine.

FIG. 9 is a schematic flowchart of a hook shaft drive control routine.

FIG. 10 is a schematic flowchart of a routine for controlling spindle / hook shaft initial setting processing.

FIG. 11 is a schematic flow chart of a routine of upper thread remaining amount securing processing control at the start of sewing.

FIG. 12 is a schematic flowchart of a shuttle shaft synchronous drive processing control routine.

FIG. 13 is a schematic flowchart of a sewing process control routine.

FIG. 14 is a schematic flow chart of a routine of the upper thread remaining amount securing processing control at the end of sewing.

FIG. 15 is a schematic flowchart of a routine of abnormality processing control.

FIG. 16 is a schematic flowchart of a thread trimming control routine.

FIG. 17 is a schematic flowchart of a cutting process control routine.

FIG. 18 is a time chart of various signals output for sewing N stitches of embroidery data.

FIG. 19 is an explanatory diagram showing a motion curve of a needle bar, a balance, a shuttle thread yarn amount curve, and a rotation position of a full-rotary shuttle in association with a rotation position of a spindle.

FIG. 20 is a diagram showing the rotary speed of the hook shaft with respect to the rotation of the main shaft at the start of sewing.

FIG. 21 is a front view of the full rotary hook temporarily stopped when the main shaft is at “300 °”.

FIG. 22 is a diagram showing the number of drive pulses of the thread trimming motor with respect to the rotation of the spindle.

FIG. 23 is a view corresponding to FIG. 6 in which the movable blade can move forward to the maximum rotation position and engage with both upper and lower threads.

FIG. 24 is a view corresponding to FIG. 6 in which the movable blade returns to the standby position and cuts the upper and lower yarns.

FIG. 25 is a diagram showing a rotary speed of a hook shaft with respect to a rotation of a main shaft at the end of sewing.

[Explanation of symbols]

 M Multi-head embroidery sewing machine 17 Sewing machine spindle 21 Needle bar 22 Sewing needle 23 Balance 47 Upper thread 48 Lower thread 52 Needle plate 55 hook module 58 hook driving motor 59 full rotation hook 80 thread trimming mechanism 81 movable blade 82 fixed blade 85 thread trimming driving mechanism 88 thread trimming motor 110 sewing machine motor 150 hook shaft controller W work cloth

Claims (4)

[Claims] 1. A sewing needle driven by a sewing machine motor via a main shaft, a thread-wheel catching hook that catches a thread wheel in cooperation with the sewing needle, and a thread-wheel catching hook driven to rotate by a driving force of a sewing machine motor. In a sewing machine having a hook driving mechanism for cutting and a thread cutting mechanism for cutting a thread under the needle plate, a driving means for driving the thread cutting mechanism and a thread cutting mechanism for activating the thread cutting mechanism at the start of sewing. A sewing machine comprising control means for controlling drive means. 2. A sewing needle and a balance that are driven by a sewing machine motor via a main shaft, a thread-wheel catching hook that catches a thread wheel in cooperation with the sewing needle, and a thread-wheel catching hook independent of the sewing machine motor. A sewing machine including a shuttle drive motor that is rotationally driven in synchronization with a main shaft, and a thread cutting mechanism that cuts a thread on a lower side of a needle plate, including a driving unit that drives the thread cutting mechanism, and a thread cutting mechanism at the start of sewing. A sewing machine comprising a control means for controlling a driving means so that the thread cutting operation is performed. 3. The sewing machine according to claim 1, wherein the driving means includes an actuator independent of a sewing machine motor. 4. The sewing machine according to claim 3, wherein the control means controls the drive means so that the thread trimming mechanism operates the thread trimming operation while the needle bar is being raised in the second cycle from the start of sewing. .