JP3465916B2 - Staggered sewing machine - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION This invention comprises an upper thread supply device
About the zigzag stitch sewing machine .

[0002]

2. Description of the Related Art In a lockstitch (straight stitch) sewing machine, the basic thread amount is first determined by detecting the feed pitch for the upper thread feed amount, and the correction according to the conditions such as the sewing machine speed and the cloth thickness is automatically corrected. Manual correction is added to make it final.

As shown in FIG. 6, the needle thread feeding mechanism has a driving motor 1, a driving roller 2 attached to an output shaft of the driving motor 1, and a driving roller 2 which is in contact with the driving roller 2. The driven roller 3 which is rotated according to the rotation of the drive roller 2, the first solenoid 5 for delivering the yarn, which is arranged between the drive roller 2 and the spool 4, and the drive roller 2 which is opposite to the first solenoid 5. A second solenoid 6 for releasing the thread arranged on the side, and the upper thread 7 wound around the thread winding 4 and passed around between the first solenoid 5, the driving roller 2 and the driven roller 3 , Is driven by the drive roller 2.

Here, the drive roller 2 and the driven roller 3 are rotated at a constant speed by the drive motor 1, and the first solenoid 5 and the second solenoid 6 hold the needle thread 7 when they are ON and are OFF. When it ’s released,
In particular, when the first solenoid 5 is ON and the upper thread 7 is restrained, the drive roller 2 and the driven roller 3 are designed so as to idle around the upper thread.

In the sewing machine driven state, first, the first solenoid 5 is turned off, and at the same time, the encoder pulse from the encoder for counting the amount of yarn contained in the drive motor 1 is measured, and the number of pulses corresponding to the set feeding amount is measured. When counting, the first solenoid 5 is turned on and the feeding of the upper thread is stopped.

During this time, the second solenoid 6 is in the ON state, and the needle thread fed by the drive roller 2 is stored between the drive roller 2 and the second solenoid 6.

Next, at the yarn feeding timing set in the sewing machine, the second solenoid 6 is turned off and the upper yarn is supplied to the balance side. The above operation is repeated for each stitch to stabilize the thread tightness in the sewing state.

In the zigzag stitch sewing machine, the basic thread amount required for one stitch is T _B1 = √ (P _F ² + P _W ² ) + H. Where P _F is the feed pitch and P _W is the zigzag stitch 1
The needle amplitude per needle, H is the cloth thickness.

A correction value according to the sewing machine speed is added to
k _1, the correction value according to the condition of the fabric species such as a k _2, the actual amount of yarn T _{B2 is, T B2 = k 1 × T} B1 + k 2 = k 1 {√ (P F 2 + P W 2)
+ H} + k ₂ .

However, as shown in FIG. 7 , in the case of four-point zigzag stitching, the needle position and, even when the fed-out thread amount T _B2 is fed out one stitch at a constant feed pitch and needle amplitude, Since the sewing unevenness occurs depending on the needle swing direction, the correction value k ₃ for further correcting it is necessary.

In this case, the upper thread payout amount T _B3 is given by the following equation.

T _B3 = T _B2 + k ₃ = k ₁ {√ (P _F ² + P _W ² ) + H} + k ₂ + k ₃

Here, k ₃ is a correction value for the needle position and the needle swinging direction, and therefore 6 kinds of k ₃ values are required for the 4-point zigzag stitch, and the k ₃ value is both positive and negative. It can take a value.

Therefore, 6 of the 4-point zigzag stitch shown in FIG.
Needle thread feeding amount T _{1 to} T for the knot points S _{1 to} S _{6
In the case of No. 6} , T _n = T _B2 + k _3n , respectively, and the tightness state of each of the knot points S _{1 to} S ₆ is determined by the needle thread feeding amounts T _{1 to} T ₆ .

[0015]

By the way, in actual sewing, even if T ₃ = 0 is controlled, the knot point S ₃ may be in a down tone. To correct this down tone, T ₃ < Although it is necessary to set the value to 0, there is a problem that the correction cannot be performed because T _n > 0 in the conventional needle thread feeding mechanism.

[0016] This invention, which was made in view of the above problems, the zigzag stitch comprises a yarn feeder on nodal points of the lower tension is to prevent sewing unevenness so as not to occur It is intended to provide a zigzag stitch sewing machine .

[0017] The present invention, in the needle, quality one adjusts the feed amount
Oite the <br/> zigzag stitch sewing machine having a thread supply device on supplying intermittently upper thread for each needle, Repetitive wherein the thread supplying device of the upper thread
It is possible to extend and pull back, and to the zigzag stitch needle position or the needle swinging direction with respect to each zigzag stitch needle position.
Setting means for setting a correction value for the upper thread feeding amount based on
Supplement for each stitch of zigzag stitch based on the setting by the setting means.
The upper thread feeding amount, which is positive, is fed out by the upper thread feeding device.
More zigzag stitch sewing machine according to claim or a control means for pulling back the, that was provided, it is to achieve the above object.

[0018] The upper thread supplying device includes a roller to draw the yarn is driven by a reversible motor, it is arranged on the yarn upstream of the roller, OF yarn feeding start timing
A first thread-constraint releasing device, which is set to F to release the upper thread and is turned on at the thread feeding end timing to restrain the upper thread, and is arranged on the downstream side of the roller with respect to the roller, during the yarn feeding. When turned ON, the upper thread is restrained, the upper thread is stored between the roller and the second thread restraining release for releasing the stored upper thread so that the stored upper thread is fed in the needle direction at the thread supply timing. apparatus and, as well as have a, by the control means reverses the motor in needle position requiring retraction thread among the needles located at the yarn pullback start timing, the roller with driving reversed yarn draw-back direction, The second yarn restraint release device may be turned off at the yarn pullback timing.

Furthermore, the needle, zigzag sewing with the needle thread supply device you supply the needle thread intermittently the feed amount per stitch one adjusting substance
Zigzag stitches on the sewing machine
Based on the needle position or needle swing direction,
A setting means for setting a correction value; an upper thread retracting mechanism which is arranged on the downstream side of the upper thread supply device for retracting the upper thread;
At the needle position that requires thread pullback amongst the zigzag stitch needle positions
The thread pullback amount is set based on the setting of the correction value by the setting means , and the upper thread pullback mechanism is set to a predetermined value based on the setting.
The control means for driving only the amount is provided, and each zigzag stitch is provided.
A needle position requiring retraction thread of needle position, the control hand
The needle thread pullback mechanism may be driven by a predetermined amount depending on the step .

[0020]

In the present invention, the needle thread pullback mechanism adjusts the amount of thread pullback at the needle position that needs to be pulled back among the needle positions of the zigzag stitch, and pulls back the upper thread. It is possible to suppress improper tightening (lower tone) at a specific needle position and prevent uneven sewing due to a difference in needle position or the like.

[0021]

Embodiments of the present invention will be described below with reference to the drawings.

A zigzag stitch sewing machine according to this embodiment (overall view)
A needle thread feeder 10 (not shown) includes a drive motor 12 including a pulse motor or a BC servo motor capable of forward / reverse rotation,
Drive roller 14 driven by this drive motor 12
And the upper thread 16 that has rolled into contact with the drive roller 14 and has been caught.
The driven roller 18 for feeding the yarn, the first solenoid 22 for delivering the yarn arranged between the spool 20 and the drive roller 14, and the drive roller 14 are provided on the opposite side of the first solenoid 22. Second solenoid 24 arranged
And the drive motor 12, the first solenoid 22 and the second
It is composed of a control device 26 for controlling the solenoid 24. Reference numeral 12A in FIG. 1 counts the number of pulses when the drive motor 12 is a pulse motor, or counts the number of pulses of an encoder synchronized with the drive motor 12 when the drive motor 12 is a BC servo motor. The pulse counter 27 for setting the pullback amount is a pullback amount setting device for setting the upper thread pullback amount in the control device 26.

The pullback amount setting device 27 is a zigzag stitch.
Each node (needle position) S₁~ S₆Corresponding to each
Needle position correction dial D for setting the upper thread pullback amount₁
~ D ₆Is equipped with.

Next, the operation of the apparatus of the above embodiment will be described.

The feeding of the needle thread is similar to that of the conventional needle thread feeder shown in FIG.

The sewing manufacturer conducts trial sewing before actual sewing, checks the sewing state, operates the needle position correction dials D _{1 to} D ₆ in the pullback amount setting device 27, and staggers. The needle thread pullback amount is corrected for each of the knotting points S _{1 to} S _{6 of the} sewing.

In this work, as shown in FIG. 2, first, initial values of the needle position correction dials D _{1 to} D ₆ are set (step 101) and then trial sewing is performed (step 1).
02).

Next, in the scan Te' flop 103 checks the sewing unevenness due needle position, in step 104, if no sewing unevenness proceeds to the normal sewing operation of step 105, if there is a sewing uneven step 106 , The needle position correction dial is adjusted, and the process returns to the trial sewing in step 102.

In this way, the needle position correction dials D _{1 to} D ₆ are adjusted until the uneven sewing is eliminated, and the regular sewing operation is started.

Here, the yarn feeding operation is stopped only when the yarn feeding amount becomes negative due to the needle position correction,
Performs the thread amount control to switch to the thread pullback operation.

Table 1 shows an example of the needle position correction dial adjustment.

[0032]

[Table 1]

[0033] Here, the feeding pitch P _F = 1 mm, 1 stitch per needle amplitude P _W = 8 / 3mm, cloth thickness H = 1 mm, the speed correction k
₁ = 1, the fabric type correction k ₂ = 0, the amount of yarn ^{_{TM = k 1 {√P F 2}} +
P _W ² } + H} + k ₂ + k _3n , and the initial value of the needle position correction dial is k _3n = 0 (n is a numerical value of 1 to 6 corresponding to S _{1 to} S ₆ ).

As shown in Table 1, in this example, in the first trial sewing, the knot point S ₂ is the upper tone and knot point S ₃
Is subordinate, k ₃₂ = 3.8, k ₃₃ = -3.8.
The second trial sewing was performed at (T ₃ = 0). Since there is uneven sewing in the second trial sewing, k ₃₂ = 4.8, k
_{The third} trial sewing was performed at ₃₃ = -4.8 (T ₃ = -1.0 mm), and the uneven sewing was eliminated.

FIG. 3 shows the control flow for feeding and pulling back the upper thread in the case of actual zigzag stitching.

In the control unit 26, step 201
, Zigzag stitch needle amplitude value, feed pitch,
Cloth thickness, the position of each needle position compensation dial, and other correction value is detected, thereby, the yarn feed amount T _n for each needle position of the zigzag stitches is calculated (see step 202).

Next, at step 203, it is judged if the sewing machine has started, and if not, step 20
Return to 1 and if positive, proceed to step 204.

In step 204, the needle position is detected, in step 205, the calculated yarn feeding amount T _n is called, and in step 206, it is determined whether T _n is positive or negative.

If it is positive, the process proceeds to step 207, and the calculated yarn amount T _n is normally paid out. If negative, the process proceeds to step 208, and the upper yarn is pulled back by the calculated negative yarn amount T _n .

The above steps are repeated until step 209.
The machine continues until it is detected that the sewing machine stops.

In the above yarn amount control flow, the process of pulling back the upper yarn at the needle position where T _n is negative will be described in detail.

In the case of a knot that is in a lower tone in the conventional needle thread feeder, in the present invention, as shown in FIG. 7, for example, when the knot point S ₃ is in a lower tone (Tn <0), When the needle goes from the bottom dead center of the node S ₂ to the top dead center, the drive motor 12 is reversed by the set amount while the first solenoid 22 is ON and the second solenoid 24 is OFF, and the upper thread is Pull back (see Figure 4).

The start timing of the pullback of the upper thread is
It is the same timing as the original thread feeding timing.

On the other hand, at the same time when the reverse rotation of the drive motor 12 is started, the pulse counter 12A starts counting the number of pulses corresponding to the rotation speed of the drive motor 12, and this coincides with the number of pulses set by the pullback amount setting device 27. At this time, the second solenoid is turned on, and at the same time the drive motor 1
Stop the reverse rotation of 2.

Reference numeral t in FIG. 4 indicates a reverse rotation time of the drive motor 12 corresponding to the needle thread withdrawal amount set by the withdrawal amount setting device 27. t is set for each knot that requires needle thread pullback.

In this embodiment, the upper yarn feeding amount is 0.
However, when the thread reaches the knot point where the tightening failure (bottom tone) still occurs, the upper thread tension is increased by pulling back the upper thread by the set amount, preventing the tightening failure and enabling sewing without sewing unevenness. Becomes

Next, a second embodiment of the present invention shown in FIG. 5 will be described.

In the second embodiment, the needle thread pull-back mechanism 3 is provided on the downstream side of the needle thread feeding mechanism 30, which is the same as the conventional needle thread feeder shown in FIG. 7, and on the upstream side of a thread balance (not shown).
2 is provided.

The upper thread pulling-back mechanism 32 arranges a pair of thread guides 34A, 34B in the middle of the path of the upper thread 16 so as to be separated from each other in the upper thread path direction.
A movable yarn guide 36 that is movable in a direction orthogonal to the upper yarn path is provided at an intermediate position of 4B.

The movable yarn guide 36 is driven by, for example, a solenoid (not shown) having a variable movement amount, and the movement amount in the direction orthogonal to the needle thread path can be controlled by the control device 26.

In the second embodiment, similarly to the first embodiment, the direction in which the movable yarn guide 36 is separated from the upper yarn path at the knot point S ₃ at which the tightening failure is expected to occur. The second solenoid 24 of the upper thread supply device is turned on at this time to stop the upper thread supply from the upstream side.

With this arrangement, as in the case of the first embodiment, the distance between the movable yarn guide 36 and the upper yarn path is h, and the distance between the pair of yarn guides 34A and 34B is l. , Δl = 2√ (h ² + (l / 2) ² ) −l.

However, in this embodiment, the movable yarn guide 3
When 6 is returned to the upper thread path, the upper thread of Δl is left over, so it is necessary to correct it in the upstream upper thread feeding mechanism 30.

In each of the above embodiments, the upper thread is restrained or released by the first solenoid 22 and the second solenoid 24, but the present invention is not limited to this, and other means, For example, the upper thread may be released or restrained by a cam mechanism or the like.

The drive source for feeding out and pulling back the upper thread is not limited to the motor, but may be another actuator such as an arm driven by a solenoid.

[Brief description of drawings]

FIG. 1 is a front view including a partial block diagram showing an embodiment of a needle thread feeder of a zigzag stitch sewing machine according to the present invention.

FIG. 2 is a flow chart showing a procedure for setting a needle position correction dial in the apparatus of the embodiment.

FIG. 3 is a flow chart showing a process of controlling an upper yarn payout amount in the apparatus of the embodiment.

FIG. 4 is a timing chart explaining the operation of the apparatus of the embodiment.

FIG. 5 is a plan view including a partial block diagram showing a second embodiment of the present invention.

FIG. 6 is a front view showing a needle thread supply device of a conventional zigzag stitch sewing machine.

FIG. 7 is a plan view showing stitches and knot points of zigzag stitches.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 10 ... needle thread supply device 12 ... drive motor 14 ... drive roller 16 ... needle thread 22 ... 1st solenoid 24 ... 2nd solenoid 26 ... control device 27 ... pullback amount setting device 28 ... pulse counter 30 ... needle thread feeding mechanism 32 ... upper thread pullback mechanism 36 ... movable thread guide D ₁ to D ₆ ... hand position correction dial

Claims (3)

(57) [Claims] 1. A needle, zigzag stitch sewing machine having a needle thread supply device for supplying intermittently upper yarn feed amount adjusting quality one for each needle
Oite to down, the upper yarn feeding devices of the upper thread feeding and
It is possible to pull it back and pair it at each needle position of the zigzag stitch .
The upper thread reel based on the needle position or needle swing direction of zigzag stitching.
Setting means for setting the correction value of the protrusion amount and 1 of zigzag stitches
After making a correction based on the setting by the setting means for each needle
Adjust the thread feed amount by feeding or pulling the upper thread feeder.
Zigzag stitch sewing machine, characterized by comprising a control means for returning, to. 2. The upper thread supply device according to claim 1,
A roller driven by a motor capable of forward and reverse rotation to pull out the yarn, and arranged on the yarn upstream side of this roller, turned off at the yarn feeding start timing to release the upper yarn, and turned on at the yarn feeding end timing. A first yarn restraint releasing device for restraining the upper yarn, and a yarn downstream side of the roller, which is turned on during the yarn feeding to restrain the upper yarn and store the upper yarn between the roller and yarn supply timing, as the thread on which gills該貯is sent to the needle direction, and a second yarn restraint release device for releasing it, as well as have a, by the control means, the pullback yarn out of the hand position The motor is rotated in the reverse direction at the required needle position, the roller is reversely driven in the yarn pullback direction at the yarn pullback start timing, and the second yarn restraint release device is turned OFF at the yarn pullback timing. Zigzag stitch sewing machine, characterized in that it is in so that. 3. A needle for adjusting the amount of feeding.OneIntermittent for each needle
The upper threadOnYarn feederStaggered sewing machine with
TheAtThe zigzag stitch needle position or needle for each zigzag stitch needle position
Setting for setting the correction value for the upper thread take-up amount based on the swing direction
A fixed means, The above Downstream of the upper thread feederPlaced and pull back the upper thread
Upper thread pullback mechanism, At the needle position that requires thread pullback amongst the zigzag stitch needle positions
Supplement by the setting means Based on positive value settingThread pullback amount
Set, The upper thread pull-back mechanism is set according to the setting.
And a control means for driving only an amount, Need to pull back the thread at each needle position of the zigzag stitch Needle position
AtBy the control means,Needle thread pullback mechanismWhere
Drive only fixed amountZigzag stitch characterized by being done
MississippiN.