JPS5919712B2 - Sewing machine drive control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a method for moving the cloth in the cloth feeding direction of the sewing machine sewing section so as to move the cloth in a direction crossing the cloth feeding direction in response to a detection signal from a sensor that detects the presence or absence of an edge of the cloth to be sewn. It relates to a drive control device for a sewing machine that is equipped with a manipulator that clamps and presses the fabric against the top surface of the bed at the front, and that controls the sewing machine drive speed in order to form an appropriate stitch at the rear end of the fabric at the end of sewing. Concerning what is possible to form a seam in the fabric.

Conventionally, when the sewing machine described above is used to sew the edges of stretchable fabric to be sewn, when the fabric pressed by the manipulator is fed forward in the fabric feeding direction at the sewing section, the fabric between the manipulator and the stitching section is stretched. The fabric is fed into the sewing section to form a seam, but when the trailing edge of the fabric passes through the manipulator at the end of the stitching and the compression is released, the fabric returns to its normal state from the temporary contraction.

For this reason, if the trailing edge of the fabric is fed at high speed from the time it passes through the manipulator to the time it moves to the stitching section, the trailing edge of the fabric will be contracted and sent to the stitching section before returning to its steady state, forming a seam. As a result, seams are formed with wrinkles in the fabric, or large seams with so-called seams where the thread line is different from the seams in the middle of the fabric, which significantly reduces the quality of the product. This resulted in a disadvantage.

This invention aims to eliminate the drawbacks of the above-mentioned conventional ones.

An embodiment of the present invention will be described with reference to the drawings. A sewing machine 1 is operated in conjunction with a motor (not shown) to stitch two chain stitches N (12th
This is a well-known decorative stitch sewing machine that forms a decorative stitch sewing machine. have the same feed amount, and are connected so that the feed amount of the sub feed dog 6 is greater than that of the main feed dog 5 by the action of the air cylinder 80 below the bed 1, making so-called differential feed possible.

At the front of the bed I in the cloth feeding direction, there is a main cloth holder which is gently curved in the cloth feeding direction and a sub holder which is connected to the curved surface of the table 90 and slopes upward in the cloth feeding direction. The cloth holders are arranged with a table 10, the main and sub cloth holders are tables 9 and 10, and an undershirt (running shirt) is placed on the side of the bed 1.
A carrier 12 is disposed that grips the hem of the body W and moves forward in the cloth feeding direction by the action of an air cylinder 110.

The presser foot 13, which is fixed to the lower end of the presser bar and moves up and down by the action of an L1 air cylinder (not shown) facing above the feed dog, is pressed against the upper edge of the bend 7 by the action of an air cylinder (not shown) at the front in the material feeding direction. The manipulator 14 (
The gear 16 at the tip is moved by the detection signal of the sensor 15 so that the edge of the cloth side is always positioned on the sensor 15 arranged between the presser foot 13 and the presser foot 13. The body W is moved in a direction crossing the cloth feeding direction by rotating forward and backward.

A binder 11 fixedly placed in front of the presser foot 13 in the cloth feeding direction gradually folds the tape T into three layers as shown in FIG. drawn out.

Regarding the cloth carrying device 18, the shoulder portion W1. of the body W held on the carrier 12. This is to send one side of W2 to the seam section before sewing starts, and is a holder 1 fixed to the surface of the sewing machine 1.
A frame body 20 is supported rotatably around a vertical axis at 9, and this frame body 20 can be elastically locked in an operating position where an engagement piece 21, which will be described later, faces above the bed surface in front of the suture portion. The stopper locking piece 36 is supported on the machine frame.

The upper end of an air cylinder 21 is rotatably supported on this frame 20 by a horizontal shaft 22, and the lower end of the plunger 23 has a protrusion 25 that loosely fits into an L-shaped groove cam 24 formed on the frame 20. A main and sub-engaging piece 2 is fixed at the lower end of the actuating piece 26 and is elastic and has an uneven lower end surface.
7a and 27b are stacked vertically and fixed.

The free ends of both engaging pieces 27a and 27b are formed into a sword-point shape along the leading edge and one side edge of the shoulder portion W1 of the body W in the cloth feeding direction, and are slightly inclined downward, and are always is separated upward from the top surface of the bed 7.

When the pin 25 moves along the grooved cam 24 in association with the lowering of the actuating piece 26 by the action of the working cylinder 210, the free end of the main engaging piece 27a moves along the vertical portion 24a of the grooved cam 24, and the free end of the main engaging piece 27a touches the edge of the shoulder w1. Both free ends of the sub-engaging piece 27b descend to the top surface of the bed and press into contact with each other so that the free end of the sub-engaging piece 27b engages with the shoulder W1 located inward from the sub-engaging piece 27b, and the horizontal part 24b
, the presser foot 13 is moved in front of the presser foot 13 in the fabric feeding direction so that the →1 edge of the shoulder W1 crosses the fabric feeding line passing through the seam and is inserted inside the crease of the tape T folded into three by the binder 11. It moves horizontally in the direction crossing the cloth feeding direction (in the direction of arrow a in FIG. 7).

℃ about the cloth guiding device 28, the main engaging piece 2 of the cloth carrying device 18
When 7a is lowered onto the bed 1, guide holes 29 are formed that vertically penetrate through the upper surface of the bed 7 at three outer positions along the leading edge in the cloth feeding direction of the free end and the edge 1j. An actuating plate 31, which has three protruding parts 30 upright that can be retracted and retracted upward from the upper surface of the bed through each guide hole 29, is rotatable about a horizontal axis relative to a support plate 32 fixed to the lower surface of the bed 7. A coil spring 33 is wound around each protrusion 30 .

The plunger 35 of the air cylinder 34 fixed to the machine frame can be engaged with the action plate 31, and its action causes the action plate 31 to
is rotated to bend the coiled spring 33 between it and the bend 1, and the protrusion 30 is made to protrude above the bend 7 through the guide hole 29.

Regarding the auxiliary valve device 31 (Fig. 1), a rod-shaped suppressor 39 whose intermediate portion is rotatably supported on the machine frame by an axis 38 orthogonal to the cloth feeding direction is bent at one end to form a presser portion 39a. This presser foot part 39a is arranged opposite to the upper surface of the throat plate 3 on one side of the presser foot 13 in front of the cloth feed direction, and the other end that stands upward is bent along the direction of its own rotational axis. A U-shaped fitting portion 39C with a gap is projected from the engaging portion 39b in the horizontal direction.

This suppressor 39 receives an elastic force in the rotating direction (clockwise in FIG. 1) by a coiled spring 40 whose one end is fixed to the machine frame so that the presser part 39a is always pressed against the upper surface of the throat plate 3. .

A connecting rod 43 is fixed to a plunger 42 of an air cylinder 41 fixed to the machine frame, and the connecting rod 43 has a guide portion 43a that slopes downward.
penetrating into the gap c and facing the lower end of the engaging portion 39b;
As the plunger 42 rises due to the action of the air cylinder 410, when the inclined guide portion 43a engages with the lower end of the engaging portion 39b of the pressing body 39 due to the rising of the connecting rod 43, the engaging portion 39b moves upward due to its inclination. In response to the component force in the lateral direction (forward in the cloth feeding direction), the pressing body 39 resists the elastic force of the coiled spring 40 and moves counterclockwise so that the °C presser portion 39b is separated upward from the throat plate 3 (FIG. 1). Rotate to.

Further, the presser foot 13 of this embodiment has a main portion 13a facing the main feed dog 5 and a presser portion 39 of the suppressor 39 from the outer end thereof.
an extension part 13b extending along the cloth feeding direction to the side of a; is a diameter portion 13C extending laterally to the holding portion 39a along the extension portion 13b.
It is composed of

In addition, the throat plate 3 corresponds to the main feed dog 5, and the front side of the needle drop point in the cloth feeding direction is lowered by the thickness of the tape T to form a stepped portion 3a.
The bent lower end of the tape T can be inserted to facilitate the loading of the body W by the engagement piece 27 of the loading device 18 and to prevent the tape T from turning over (FIGS. 5 and 6).

Regarding the tape tension device 44 (FIG. 2), a pair of support stands 45 are fixed to the front side of the sewing machine 10, and three tape guide rods, which will be described later, are provided on each support stand 45.

In both of the support stands 45, a fixed guide rod 46 that stands up on one side of the moving path of the tape T moving along a linear path is fixed to each support stand 45, and a vertical axis is attached to each support stand 45. The rotary bodies 41 are individually supported so as to be rotatable around 1.
A first guide rod 48a facing one side of the linear movement path of the tape and a second guide rod 48b facing the other side, like the fixed guide rod 46, are erected and fixed to the rotating body 41. One tape T When the tape T is transferred along a straight path, the first and second guide rods 48a of the rotary body 47 in the forward direction of the tape T movement direction are moved.
, b and the second guide rod 48b of the rotating body 47 in the forward direction of movement do not touch the tape T.

A plunger 50 of an air cylinder 49 fixed to the machine frame is connected to an actuating body 51 connected to the rotating bodies 47 of both support stands 45, and when the actuating body 51 is in operation, the first and second guide rods 48a are connected.

Rotating body 4 so that 48b intersects the moving path of tape T.
7 by 7 fixed angles, and the tape T is connected to the fixed guide rod 46.
and the second guide rods 48a and 48b to form an L-shape and apply a predetermined tension.

Regarding the tape cutter device 52 (FIG. 1), presser foot 1
At the rear of the sewing machine 1 in the cloth feeding direction, a fixed blade 53 is fixedly disposed on the upper surface of the bend 7, crossing the cloth feeding direction and facing the moving path of the tape T sewn to the body W. A movable blade 55 rotatably supported around an axis 54 along 1 is an electromagnet 5 whose base end is fixed to the machine frame.
6, the blade portion 55a at the tip faces above the fixed blade 53, and when it rotates due to the action of the electromagnet 56, the tape T moving on the fixed blade 53 can be cut by the cooperation of both.

Regarding the blower device (FIG. 1), two pipes 57 and 58 fixed to the frame 20 of the carrying device 18 have their proximal ends connected to a compressed air source (not shown) with solenoid valves v9. ℃ via v1o
The open end of one of the tubes 57 is connected to the engaging piece 27.
The lowered position of the tube 58 is opposite to the upper side and is not close to the cloth feed line passing through the seam part (arranged so that the hole is opened downward along the direction crossing the cloth feed direction, and the other tube 58 is located outward from it). The holes are arranged so as to open downward along the cloth feeding direction.

Cloth sensor 59 = 60 a * 60 b is the light source (
(not shown) to detect the presence or absence of cloth on the bend 7, and generate cloth detection signals for each state.

The cloth sensor 59 is arranged on the side of the manipulator 14 in front of the guide hole 29 of the bed 70 in the cloth feeding direction, and is for detecting that the shoulder W1 of the body W is arranged along the protrusion 30 at the beginning of sewing. , sensor 60 a *
60b are placed on the side of the presser foot 13, spaced apart from each other in the cloth feeding direction, and are used to set the activation timing of the electromagnet 56 of the tape cutter device 52, and only one of them is always selectively activated. will be activated.

That is, the sensor 60a at the rear in the cloth feeding direction is used when cutting the body W with the tape T protruding a predetermined length from the leading edge of the cloth, and the sensor 60b at the front in the cloth feeding direction is used when cutting the tape T from the rear edge of the cloth of the body W. Used when cutting a T with a predetermined length protruding from it.

It should be noted that the sewing machine of this embodiment is designed to always stop in accordance with the needle down position.

Next, the electric circuit of this embodiment will be explained.

In the figure, ■1 to VIO are the solenoid valves of each air cylinder, vl is the solenoid valve of the air cylinder 21 of the cloth carrying device 18, V2 is the solenoid valve of the air cylinder 34 of the cloth guide device 28, and V3 is the solenoid valve of the air cylinder 34 of the cloth guide device 28. V4 is a solenoid valve of an air cylinder (not shown) for pressing the manibulator 14 onto the upper surface of the bed 1; ■5 is an air cylinder 11 that operates the commercial carrier 12; solenoid valve, V6 is air cylinder 8 for differential feeding
V7 is the solenoid valve of the air cylinder 49 of the tape tension device 44, V8 is the solenoid valve of the air cylinder 41 of the auxiliary footing device 37, and V9 is the solenoid valve of the air cylinder 41 of the blower device 5.
7 is a solenoid valve that opens and closes the air flow generated in pipe 5, Vlo is
This is a solenoid valve that opens and closes the air flow generated at 8.

These solenoid valves V1 to V1° are individually activated or deactivated under the control of the respective solenoid valve control circuits C1 to CIO.

In particular, the air cylinder 110 control circuit C5 of the commercial carrier 12 controls the solenoid valve V5 so that the carrier 12 moves at approximately the same speed as the moving speed of the body W driven by the sewing machine.

2 is a buzzer that generates an alarm, and the buzzer control circuit C1
Sound is generated intermittently for a time set by the operator under the control of l.

The electromagnet 56 of the tape cutter device 52 is energized for a certain period of time and then deenergized under the control of the electromagnet control circuit C12.

M is a motor connected to the main shaft of the sewing machine (not shown), which is driven or stopped under the control of the motor control circuit C□3, and when driven, is driven by the drive current from either the low-speed drive circuit D1 or the high-speed drive circuit D2. Driven.

The low feed drive circuit D0 drives the motor M at a constant low speed,
The high speed drive circuit D2 is set to the medium speed 1 specified by the speed setting circuit.
Drive on one hand at high speed.

The driving speed in line sections X and y, which will be described later, is set in the speed setting circuit, and these speeds are set so that x>y.

x and y are stitch count setting circuits that respectively set the number of stitches to sew the straight section The number of stitches can be set.

E 1 and E 2 are comparison circuits, and the needle position detection means P
El generates a match signal when the count value matches the number of stitches set by the stitch count setting circuit X, and E2 counts the position signal from E□. In connection with generation of the coincidence signal, position signals are started to be counted, and when the number of stitches set by the setting circuit Y matches the counted value, a coincidence signal is generated.

F is a switching circuit, which is a control circuit C6 for solenoid valves v6 to V9.
The operation timing is selectively set in one of the sewing sections X or y so that C9 and the high-speed drive circuit D2 are activated when a stitch is formed in a predetermined one of the sewing sections X or y.

S is a solenoid valve V6 that creates a differential feed and tape tension device. This is a selection switch that enables or disables v7.

T1 to TIO are each different set times △t1 to △tl
It is a timer circuit with o, especially T1゜T6 s
'r9 allows the setting time to be adjusted externally, and T3
The timer is set for 1 hour until the shoulder W1, which is held between the bed I by the engagement piece 27 of the carry-in device 18, is sent by the feed dog 5.6 and the first needle drops. T4 is configured so that its own set time expires after the set time of T3 expires.

The present invention has the above-mentioned configuration, and the operation of this embodiment will be explained based on the time chart shown in FIG. 15.

In the initial state, both the solenoid valves V2 and V3 of the air cylinder (not shown) that raises and lowers the presser bar and the air cylinder 34 of the cloth guide device 28 are open, and the presser foot 13 is separated above the throat plate 3 and the actuating plate A protrusion 30 of 31 protrudes upward from the guide hole 29 of the bed 70.

Set the selection switch S to the "1 enabled" side.

When the tip of the shoulder part W1 of the undershirt W is placed along the protruding part 30 as shown in FIG. The solenoid valve V9 is opened so that an opening sound for a set time Δt1 of T1 is generated intermittently and an air flow is generated in the pipe 57.

The wrinkles of the shoulder W1 along the protrusion 30 are smoothed out by the air flow from the tube 57, and the shoulder W1 is brought into close contact with the upper surface of the pend 7, and Δt1
After the elapsed time, the buzzer Z stops sounding and the solenoid valve v9 closes, and the solenoid valve v1 of the air cylinder 21 of the carrying device 18 closes.
and close the solenoid valve v2 of the air cylinder 34 of the cloth guide device 28.

The protruding part 30 descends below the bed 7, and the pin 25 is guided by the vertical part 24a of the grooved cam 24, and the main and sub-engaging pieces 27a,
27b descends and the distance between shoulder W1 and the top surface of bend 7 is 1/(
At the same time, the pin 25 is guided by the horizontal part 24b, and the main and sub engaging pieces 27a and 27b move in the direction of the arrow in FIG. Insert the loose end into the fold of the tape T, and place the tip edge corresponding to the tip of the presser foot 13 (see Fig. 7W).
'1).

In this state, since the side edge of the undershirt W is located on the °C sensor 15 (Fig. 7), a cloth detection signal is generated from the sensor 15, and this signal closes the °C solenoid valve v3 to close the presser foot 13. The gear 1 at the tip of the manipulator 14 is lowered and the solenoid valve v4 of the air cylinder (not shown) of the manipulator 14 is opened.
6 holds the body part W and presses it against the surface of the bed 7 with an appropriate force, and also sets the timer T2sT3.

After Δt2 of the timer T2 has elapsed, the motor M is driven by the output of the motor control circuit C13 at a low speed set by the low speed drive circuit Dl, and also acts on the switching circuit F to change the undershirt straight section X (13th ), and at the same time open the solenoid valve VIO of the pipe 58 to generate an air flow in the forward direction in the cloth feeding direction.
It acts to transport the cloth forward in the cloth feeding direction, and also controls the timer circuits T4s and T5.

The sewing machine 1 is driven at low speed for a period of Δt4 after being started, during which time the body W and tape T are transferred to the sewing part by the feed dog, and a seam is formed at the tip in the cloth feed direction almost at the same time ( To be precise, when the needle descends to the lower position), the set time Δt3 of the timer circuit T3 ends, the solenoid valve v1 of the air cylinder 21 closes, the engagement piece 21 of the carrying device 18 returns, and immediately after that, When the set time Δt4 of the timer circuit T4 ends and the high-speed drive circuit D2 is activated, the circuit D2 supplies current to the motor M so as to drive the motor M at the high speed specified by the speed setting circuit. Thereafter, the leading edge of the body part W reaches the sensor 60a, generates a detection signal, and sends the timer circuit T6.

Immediately after that, the set time Δt5 of the timer circuit T5 ends, and the solenoid valve ■5 of the air cylinder 11 of the carrier 12 is opened.
The carrier 12 moves forward in the cloth feeding direction at approximately the same speed as the movement speed of the body W by the sewing machine 1.

When the set time Δt6 of the timer circuit T6 ends, the electromagnet 5
6 is energized, the movable blade 55 of the tape canter device 52 rotates and cuts the tape T protruding from the front end of the cloth of the body W in cooperation with the fixed blade 53.

When the sewing machine is started, the gear 16 of the manipulator 14 controls the movement of the body W in a direction intersecting the cloth feeding direction, based on the cloth detection operation of the sensor 15, so as to feed the side edge of the body W to the seam part. Furthermore, the comparison circuit E1 is connected to the needle position detection means P.
Count the needle position signals from.

When the counted value matches the preset count of the stitch count setting circuit X, which is set in advance to the number of stitches required to sew the straight line section , a coincidence signal is generated from the comparator circuit E1 to put the comparator circuit E2 into the active state and switch the switching circuit F to the circuit state for sewing the curve section y, and the drive speed of the motor M is controlled by the setting circuit K by its output. do.

In addition, the output controls the control circuits C6 to C9 to each solenoid valve V6.
~V9 is controlled to open.

It is difficult to stitch this curve section y.

In other words, the gear 16 of the manipulator 14 controls the cloth so that the cloth side edge is always positioned on the sensor 15, so that when the cloth side edge has a large curve, the cloth of the sensor 15 is moved as shown in FIG. The fabric side edge on the front side in the feeding direction moves outward with respect to the fabric feeding line passing through the seam portion (double-dashed line).

Therefore, the body W fed into the stitching portion may be deviated from the folds of the tape T, or may be sewn in a deviated state.

However, here, the speed of the sewing machine motor M is lowered to facilitate cloth control by the manipulator 14, and the solenoid valve v9 of the pipe 57 is opened to direct the air flow in the direction of the arrow g (
9), the solenoid valve V8 is opened, the press body 39 of the auxiliary valve stop device 37 rotates, and the presser foot 39a presses against the presser foot 13. By pressing the body W against the bed 1 side at the front side in the feeding direction, a rotation moment is applied to the body W in the counterclockwise direction (FIG. 9) around the presser part 39a, and
Due to this airflow and rotational moment, the body part W between the sensor 15 and the seam part receives a force acting in the direction of the cloth feed line, causing its edge to lie along the inside of the folded part of the tape T.

When the body W is moved in the direction of the cloth feeding line by this presser foot 39a, in front of the presser foot 13 in the cloth feeding direction,
When the extension part 13b of the presser foot 13 is not present (as shown in FIG.
However, if the extension part 13b is provided as in this embodiment, the body part W is held down by the extension part 13b, so no large wrinkles are formed.

Furthermore, it is well known that undershirts are made of knitted fabric that is stretchable in one direction, and that this knitted fabric is sewn to stretch in the horizontal direction. If the same presser foot pressure is applied when sewing the curved section y along the curved section y, the fabric will be sewn together with the tape T while being stretched when sewing the curved section y, so the net feed amount between the body and the tape will be different and the stitching will be different. After that, the body W shrinks, resulting in wrinkles.

Therefore, as in this embodiment, the feed amount of the sub feed dog 6 which opens the solenoid valve V6 of the air cylinder 8 and transfers the body W while sandwiching it between the diameter part 13C of the presser foot is larger than that of the main feed dog 5. When "differential feeding" is performed so that the body part W is fed, the degree of elongation of the body W is reduced.

In addition, the solenoid valve v7 of the air cylinder 49 is opened to apply the air cylinder 49 to the tape tension device 440 and the rotating body 41.
When the first and second guide rods 48a and 48b intersect the moving path of the tape T and bend the tape into a "V" shape, tension is applied to the tape T. The tape in between is stretched and transferred to the suture area.

Due to the synergistic effect of the reduction in elongation of the body W due to differential feeding and the elongation of the tape due to tape tension, the amount of elongation of the body W and tape T during stitching is equalized, and no sewing wrinkles occur on the body W after stitching.

After switching the switching circuit F, the comparator circuit E2 counts the needle position signal from the needle position detecting means, and when the counted value matches the set number of stitches of the stitch number setting circuit Y, that is, the curve section y and the next When the boundary with straight section X reaches the seam, comparison circuit E
A coincidence signal is generated from 2 and switches the switching circuit F to the circuit state for sewing the straight section X, and solenoid valves V6 t V7 t
Vg is closed, the differential, tape tension, and feed blower devices are rendered inactive at L° C., and the speed setting circuit K is controlled so that the motor M is driven at high speed again.

(However, the comparison circuit E1 is not enabled.

) When the rear edge of the body part W in the cloth feeding direction passes the sensor 59, the detection signal causes the timer circuit T7 to be cassetted, the high speed drive circuit D2 becomes inactive for the set time Δt7, and the low speed drive circuit D1 starts the motor M. is driven at a predetermined low speed, the rear edge of the body W passes through the manipulator 14, and when the sensor 15 detects the cloth rear edge of the body W, the timer circuit T8 is set by the detection signal, and the set time is set. During Δt8, the set time Δt7 of the timer circuit T7 ends, and the high-speed drive circuit D2 drives the motor M at high speed again.

While the body part W was being pressed by the manipulator 14, it was stretched and fed between the seam part by the pressing force, but when the rear end passed through the manipulator 14 and the pressing force was released, the body part W was temporarily stretched. is contracted and then returns to a steady state.

In this embodiment, the set time Δt7 of the timer circuit T7 ends after the body W returns to a steady state, and the sewing machine is then driven at high speed.

Immediately after the motor M is driven at high speed, the set time Δt8 of the timer circuit T8 ends, the solenoid valve v4 closes, and the manipulator 14 is separated upward from the upper surface of the bed 7.

The sensor 60b detects the rear end of the body W, and the timer circuit T9 is set based on the detection signal, and the set time Δt
9, the solenoid valve v5 of the air cylinder 11 is closed to return the carrier 12, and the electromagnet 56 is energized to operate the movable blade 55 of the tape cutter device 52, so that the tape is connected to the rear end of the body W. At the same time as cutting the tape T, the solenoid valve v2 is opened and the air cylinder 34 of the cloth guide device 28 is activated to rotate the operating plate 31 so that the protrusion 30 protrudes from the guide hole 29 of the bed T. At this time, the motor control circuit C13 is actuated to stop the motor M and stop the sewing machine 1 at the needle down position.

(The fixed position stopping means is not shown because it is well known.

) At the same time, the solenoid valve v5 of the air cylinder 11 of the carrier 12 closes and returns to its original position, closes the solenoid valve VIO of the pipe 58 to cut off the air flow, and further closes the solenoid valve VIO of the air cylinder 41 of the auxiliary holding device 31. Valve V8 closes and suppressor 39 returns to its original position, setting timer circuit TIO.

Since the suppressing body 39 acts until the end of this sewing, cloth feeding after the rear edge of the body W passes through the manipulator 14 is stabilized.

That is, as is clear from FIG. 10A, only the sub-feed dog 6 directly engages the body part W before the needle drop point in the cloth feed direction, and this sub-feed dog 6 is used to feed the fabric past the needle drop point. Since the body W is located outward from the line, an outward rotational moment is applied to the body W, and after the rear end edge of the body W comes out of the manipulator 14 until it is sent to the suture section, the body W rotates to the left in FIG. (Left side in Figure 1), the tape T comes off from inside the bent part, but the presser part 39a of the suppressor 39 engages with the body and as described above, the tape T comes off in the opposite direction to the feed dog 6. It acts to apply a rotational moment so that the edge of the body W is always located within the folded portion of the tape T.

After that, the set time Δti of the timer circuit TIO.

When this is completed, the solenoid valve 3 is closed and the presser foot 13 is moved away above the throat plate 3.

When you want to use the front side of the seam widely for threading or other tasks, remove the frame 20 of the fabric loading device 18 from the locking piece 36 and rotate it toward the rear of the sewing machine about the vertical axis. By making it wider, tasks such as threading become easier.

As described above, according to the present invention, the sewing machine is driven at a low speed for a time longer than the time required for the stretched cloth to return to a steady state after the trailing edge of the cloth passes through the suppression position of the manipulator. This ensures that the trailing edge of the fabric returns to a steady state before being sent to the sewing section, so when forming the seam at the trailing edge of the fabric, a seam with no wrinkles and less uneven stitching can be obtained, improving the quality of the product. An improvement effect can be obtained.

In this embodiment, a sensor 59 is provided above the suppressed position of the manipulator as a detection means, but a counter or timer that counts the number of stitches can be used to detect when the trailing edge of the cloth moves to the suppressed position of the manipulator. A similar effect can be obtained by doing so.

[Brief explanation of drawings]

Fig. 1 is a perspective view of the sewing machine of this embodiment as seen from the rear side, Fig. 2 is a perspective view of the sewing machine as seen from the front side, Fig. 3 is a perspective view of the presser foot, feed dog, and throat plate; The figure is a perspective view of the loading device.
FIG. 5 is a partial sectional view showing the operation of the loading device in its initial state;
Fig. 6 is a partial cross-sectional view showing the late-stage action of the carrying device, Fig. 7 is a plan view of the vicinity of the sutured portion showing the action of the carrying device, Fig. 8 is a perspective view of the guide device, and Fig. 9 shows the movement of the cloth. Fig. 10A is a sectional view of the cloth feeding section of this embodiment;
The opening is a cross-sectional view of a conventional cloth feeder, FIG. 11 is a perspective view showing the folded state of the tape, FIG. 12 is a perspective view showing the sewing state of the body and the tape, and FIG. 13 is a perspective view of the undershirt. FIG. 14 is a block diagram of the electric circuit, and FIG. 15 is a time chart.

Claims (1)

[Scope of Claims] 1. Fabric feeding at a fixed reference line that is arranged in front of the sewing machine stitching section in the fabric feeding direction, is spaced to one side with respect to the fabric feeding line that passes through the stitching section, and is parallel to the fabric feeding direction. A sensor 15 detects the presence or absence of an edge to be sewn along the direction and generates a respective signal, and a sensor 15 is placed in front of the sensor in the cloth feeding direction and responds to the sensor's signal to move forward and backward around an axis parallel to the cloth feeding direction. A sewing machine that has a rotary body 16 that can be rotated and a manipulator that pinches and presses the cloth against the upper surface of the bed, and forms stitches on cloth that is stretchable in the cloth feeding direction. a detection means for detecting when the edge passes through a suppressed position of the rotating body of the manipulator and generating a detection signal; a first state in which the sewing machine is driven at a specific low speed; and a second state in which the sewing machine is driven at a specific high speed. A drive means C13 that is switchable; a setting means that operates in conjunction with the generation of the detection signal and generates an action signal within a specific time after the detection signal is generated; associated control means for switching the drive means from the second state to the first state during the period in which the setting means is operating; The sewing machine's drive control device is set longer than the time required for the fabric to return to a steady state.