CN110714280A

CN110714280A - Fabric adjusting device of sewing machine

Info

Publication number: CN110714280A
Application number: CN201910564912.4A
Authority: CN
Inventors: 林田高幸; 射场隆史; 尾崎启二
Original assignee: Yamato Sewing Machine Mfg Co Ltd
Current assignee: Yamato Sewing Machine Mfg Co Ltd
Priority date: 2018-07-11
Filing date: 2019-06-27
Publication date: 2020-01-21
Also published as: TW202012724A; JP2020006124A

Abstract

The invention provides a fabric adjusting device of a sewing machine, comprising: a sewing machine including a fabric guide section and a fabric turn-back guide device; a holding part at the other end of the fabric; and a fabric end edge position adjusting mechanism configured to be capable of driving the fabric other end gripper or the fabric intermediate holder to reciprocate in a specific direction so as to position-adjust the end edge position on the one end side of the fabric in a direction orthogonal to the sewing direction of travel, and to control the fabric end edge position adjusting mechanism to reciprocate in the vertical direction based on the result of detection of the fabric end edge position by the fabric end edge position detector so that the end edge position on the one end side of the fabric is adjusted to a predetermined position.

Description

Fabric adjusting device of sewing machine

Technical Field

The present invention relates to a fabric adjusting device of a sewing machine, for example, a double-needle horizontal-cylinder double-thread lockstitch sewing machine is used for performing hemming sewing on the whole circumference of an end part of a round fabric such as a T-shirt so as to prevent thread opening, so that a skirt is in a state of unfolding a strip of skirt fabric rather than a ring shape and the end part of the skirt is folded in two and then is subjected to hemming sewing, or a lockstitch sewing machine is used for performing end part stitch sewing on the whole circumference of an overlapped part of one end part of the round fabric, or a skirt is in a state of unfolding a strip of skirt fabric rather than a ring shape and the end part of the skirt is folded in two and then is subjected to end part stitch sewing, so that the position of a side end edge of one end part of the fabric is adjusted to a specified position. In the present specification, the various types of sewing described above are collectively referred to as hemming sewing.

Background

For example, when hemming an end portion of a round material such as a T-shirt using a two-thread lockstitch sewing machine, conventionally, it has been a common situation that a sewing operator holds an end portion of the material on one end side with a right hand and guides the material to be conveyed toward a sewing portion of the sewing machine, holds the other end portion of the round material with a left hand and slightly lifts the material above the end portion, and guides the other end portion on the left hand side to convey the material according to the degree of progress of hemming sewing, thereby the sewing operator manually assists hemming sewing with both hands.

However, in the case of the above-described manual assistance which has been conventionally performed in general, the end portion of the fabric on the one end side is displaced in a direction (hereinafter, referred to as a left-right direction) orthogonal to the sewing traveling direction by an external force such as the weight of the fabric, the end edge position of the end portion is displaced from a predetermined position by the displacement, and the end portion is likely to be displaced to the left from the sewing portion of the sewing machine, and as a result, the following problems are caused: the folded width or the overlapped portion on the one end portion side of the fabric becomes too large or insufficient, and it is difficult for a sewing operator with low skill to perform appropriate and good hemming sewing.

Therefore, conventionally, as disclosed in, for example, japanese patent laid-open publication No. 2016 and 116636, the following facing adjusting device has been proposed: a conveyor belt having a conveying surface and movable in the left-right direction is arranged at a position upstream of a sewing portion including a needle drop portion in a sewing advancing direction and below a fabric conveying path, and a fabric presser foot is arranged to be movable in the up-down direction, and has an action end facing the conveying surface of the conveyor belt via the fabric conveying path above the conveyor belt, and the fabric presser foot is moved up and down to clamp one end of the fabric between the action end of the fabric presser foot and the conveyor belt based on detection of a fabric end edge by a fabric end detector arranged at a position upstream of the sewing advancing direction relative to the facing portions of the conveyor belt and the fabric presser foot, and the conveyor belt is operated to move the clamping portion in the left-right direction in this state, thereby automatically correcting displacement of the fabric in the left-right direction, therefore, the edge on the one end portion side of the fabric can be always adjusted to a predetermined position.

Disclosure of Invention

However, according to the material adjusting device disclosed in japanese patent application laid-open No. 2016-116636, for example, when a stretchable material such as a knitted fabric is to be sewn, even if the one end portion side of the material is held between the conveyor belt and the working end of the material presser foot and moved in the left-right direction, there is a possibility that the material to be subsequently conveyed cannot be moved to a predetermined position only by the partial movement of the holding portion, that is, the end edge of the entire length of the one end portion side of the material cannot be adjusted to a predetermined position.

Further, when the one end side edge of the fabric to be sewn is curved, there is a problem as follows: since the lateral displacement of the end edge becomes large, it is difficult to adjust the position of the end edge on the one end portion side of the fabric over the entire length of the end edge, and thus appropriate and satisfactory hemming sewing cannot be performed.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a fabric adjusting device for a sewing machine, which can automatically adjust an end edge of one end portion side of a fabric to a predetermined position over the entire length of the end edge even if a sewing object is a fabric having elasticity or a fabric having a curved end edge, and can always perform appropriate and satisfactory hemming sewing.

In order to achieve the above object, the present invention relates to a fabric adjusting device for a sewing machine, comprising: a sewing machine body, comprising: a needle plate for guiding the feeding of the fabric in the sewing advancing direction; a needle configured to be movable up and down so as to pass through a needle drop portion formed in the needle plate; a fabric presser foot capable of lifting; a fabric end edge guide device which is arranged at a position closer to the upstream side of the needle drop part in the sewing advancing direction, and is in sliding contact with one end edge of the fabric to guide the movement of the end edge in the sewing advancing direction; and a fabric guide section which is disposed at a position upstream of the fabric end guide device in a sewing direction and guides a conveying movement of the fabric end side to the fabric end edge guide device; and a fabric other end holding member which is disposed on an upstream side in a sewing advancing direction from the needle drop portion and at a position spaced apart in a direction orthogonal to the sewing advancing direction toward a lateral outer side of the sewing machine main body, and which is capable of holding the other end side of the fabric, the fabric adjusting device of the sewing machine comprising: a fabric end edge position adjusting mechanism configured to be capable of driving the fabric other end holding piece or a fabric middle holding piece arranged between the fabric other end holding piece and the fabric guide part to hold a fabric middle part to reciprocate along a specific direction so that an end edge position of one end part side of the fabric is subjected to position adjustment in a direction orthogonal to a sewing advancing direction; a fabric edge position detector disposed below the fabric guide portion and detecting a position of an edge of one end of the fabric; and a control unit that drives the fabric edge position adjustment mechanism to reciprocate in the specific direction based on a detection result of the fabric edge position by the fabric edge position detector so that the edge position on the one end portion side of the fabric is adjusted to a predetermined position.

Effects of the invention

According to the fabric adjusting device of the sewing machine of the present invention having the above-described features, for example, in the case of performing hemming sewing on an end portion of a round fabric such as a T-shirt or performing hemming sewing after folding the end portion of 1 piece of skirt fabric in half in a state where the end portion is unfolded, a sewing operator places one end portion side of the fabric as a sewing portion on the needle plate of the sewing machine main body and the fabric guide portion with the right hand, and starts the operation in a state where the other end portion side of the fabric is held by the fabric other end gripper or the fabric intermediate portion holder holds the fabric intermediate portion between the fabric other end gripper and the fabric guide portion, whereby one end portion side edge of the fabric conveyed toward the sewing traveling direction through the fabric guide portion is conveyed and moved to the needle drop portion of the needle plate in a state where the one end portion side edge of the fabric is brought into sliding contact with a part of the fabric end guide device, performing predetermined hemming sewing. In such hemming sewing, the edge on the one end portion side of the fabric may be displaced in the left-right direction by an external force such as the weight of the fabric middle portion applied during the conveyance movement, and particularly, in the case of a fabric having a curved edge, the displacement in the left-right direction becomes remarkable.

When the end edge position of the one end portion side of the fabric deviates from the predetermined position in accordance with the displacement in the left-right direction, the fabric other end gripper or the fabric intermediate holder is driven to reciprocate in the specific direction by the operation control of the fabric end edge position adjustment mechanism based on the detection result of the fabric end edge position detector. Therefore, the following effects are achieved: even if the sewing object is a stretchable fabric or a fabric having a curved end edge, the end edge of the fabric on the end edge side can be automatically adjusted to a predetermined position over the entire length of the end edge, and appropriate and satisfactory hemming sewing can be always performed.

In the fabric adjusting apparatus for a sewing machine according to the present invention, it is preferable that the sewing machine main body is a hemming sewing machine as an application target sewing machine, and the fabric adjusting apparatus includes: the needle plate is used for placing an overlapped part formed by turning back one end part of the fabric and guiding the overlapped part to convey in the sewing advancing direction; the needle; and the presser foot, in addition to the above, may be one of a double-lockstitch sewing machine and a lockstitch sewing machine, wherein the double-lockstitch sewing machine includes: the needle plate is used for placing an overlapped part formed by turning back one end part of the circular fabric and guiding the overlapped part to convey in the sewing advancing direction; a plurality of needles arranged in parallel in a direction substantially orthogonal to a sewing advancing direction; and a looper which is capable of advancing and retracting in a direction substantially orthogonal to a sewing advancing direction between one side portion and the other side portion of the plurality of needles so as to hold a looper thread, and which grips a plurality of needle loops formed by the plurality of needles under the needle plate during the advancing operation, and forms a double-lock stitch over the entire circumference of an overlapping portion of one end portion of the circular fabric by the sewing operation, the overlock sewing machine comprising: the needle plate is used for placing an overlapped part formed by turning back one end part of the circular fabric and guiding the overlapped part to convey in the sewing advancing direction; a needle configured to move up and down so as to pass through a needle drop portion formed in the needle plate while holding a needle thread; and a looper for holding a looper thread, wherein a stitch of a lockstitch is formed on the entire circumference of the overlapping portion of the one end portion of the round material fabric by a sewing operation.

In the fabric adjusting device for a sewing machine according to the present invention, it is preferable that a curl correcting device for correcting a curl generated at one end side edge of the fabric is provided at the fabric guide.

In this case, when a curl is generated at the one end side edge of the fabric conveyed and moved from the fabric guide portion toward the fabric end edge guide device, the end edge after the curl correction can be conveyed to the fabric end edge guide device, and the adjustment process of the one end side of the fabric for the predetermined hemming sewing can be performed more reliably and appropriately.

In the fabric adjusting apparatus for a sewing machine according to the present invention, the specific direction in which the fabric other end gripper or the fabric intermediate holder of the fabric end position adjusting mechanism is driven to reciprocate based on the detection result of the fabric end position by the fabric end position detector may be any one of a vertical direction, a horizontal direction, a front-rear direction (sewing traveling direction), and a vertical direction.

In the fabric adjusting apparatus for a sewing machine according to the present invention, it is preferable that the fabric end edge position detector is disposed in two at an interval in a direction orthogonal to a sewing traveling direction, and the fabric end edge position adjusting mechanism is driven to move in one of the specific directions based on a detection operation of one of the fabric end edge position detectors, and the fabric end edge position adjusting mechanism is driven to move in the other of the specific directions based on a detection operation of the other fabric end edge position detector.

In this case, since there are two fabric edge position detectors, it is possible to detect which direction the displacement of the fabric to be sewn is in the left-right direction, and to drive the fabric edge position adjustment mechanism to move in a specific direction corresponding to the detected displacement direction, thereby making it possible to accelerate the reaction speed of the position adjustment operation of the fabric edge position.

In the fabric adjusting apparatus for a sewing machine according to the present invention, it is preferable that the other-end-of-fabric grip is configured to be capable of driving the other-end-of-fabric grip to rotate around a vertical or substantially vertical axis in synchronization with a sewing operation of the sewing machine main body.

In this case, when sewing the stitches on the entire circumference of the overlapping portion of the one end portion side of the fabric of the round object, the other end portion of the fabric held by the other end holding piece of the fabric can be automatically rotated in cooperation with the rotational movement for the entire circumference sewing of the one end portion side of the fabric, and thus the load applied to the sewing portion due to the twisting of the both end portions of the fabric can be reduced, and more preferable hemming sewing can be performed.

In the fabric adjusting device of a sewing machine according to the present invention, it is preferable that the fabric intermediate portion holder driven by the fabric edge position adjusting mechanism to reciprocate in the vertical direction includes: the fabric cutting device includes a roller for supporting and holding an intermediate portion of fabric from below, and a fixed mandrel for rotatably supporting the roller. In particular, when the fabric intermediate portion holder is driven to reciprocate in the vertical direction by the fabric end edge position adjusting mechanism, the roll of the fabric intermediate portion holder is preferably configured such that the fabric intermediate portion held by the roll is brought into sliding contact with an elastic member erected along the vertical reciprocating drive movement path side of the fabric intermediate portion holder, and the roll is rotated in the forward and backward directions by the fabric intermediate portion moving in the vertical direction.

In this case, since the fabric intermediate portion holder is rotatably supported by the fixed core shaft, the roller that supports and holds the fabric intermediate portion from below is rotated by the moving force when the fabric intermediate portion moves in the vertical direction by the reciprocating driving movement of the fabric end edge position adjusting mechanism, and therefore, the function of automatically adjusting the end edge on the side of one end portion of the fabric to a predetermined position over the entire length of the end edge can be reliably and responsively performed.

Drawings

Fig. 1 is a perspective view of the entire cloth adjusting apparatus of a sewing machine using a double-needle type horizontal tubular double-thread lockstitch sewing machine according to a first embodiment of the present invention, as viewed from the front right.

Fig. 2 is an enlarged perspective view of a fabric guide portion as a main part of the fabric adjusting apparatus of the sewing machine.

Fig. 3 is a perspective view of a main part showing a state before the operation of the cloth adjusting apparatus of the sewing machine.

Fig. 4 is a perspective view of a main part showing a state in which the fabric is set in the fabric adjusting device of the sewing machine.

Fig. 5 is a perspective view of a main part showing a fabric adjusting operation state of the fabric adjusting device of the sewing machine.

Fig. 6 is a perspective view showing a main part of a fabric adjusting operation state of a fabric adjusting apparatus for a sewing machine according to a second embodiment of the present invention.

Description of the reference numerals

4 machine needle

5 Fabric presser foot

6 needle plate

7 Fabric folding guide device (fabric edge guide device)

8 Fabric guide part

9 curl correcting device

10 fabric end edge position detector

10A left side light sensor

10B right side optical sensor

13 shell fabric other end gripping member

14-fabric intermediate part holder

14A roller

14B fixed core shaft

15 fabric end edge position adjusting mechanism

22 sponge component (elastic component)

M double-thread lockstitch sewing machine

H fabric adjusting device

W sewing material (round material)

Sewn part of Wa fabric on one end side

The other end part of Wb fabric

Middle part of Wc fabric

Y sewing direction

Detailed Description

Hereinafter, a first embodiment of the present invention will be described with reference to the drawings.

Fig. 1 is a perspective view of the entire fabric adjusting apparatus of a sewing machine using a double-needle type horizontal tubular double-thread lockstitch sewing machine as a sewing machine main body as viewed from the front right side, fig. 2 is an enlarged perspective view of a fabric guide portion which is a main part of the fabric adjusting apparatus of the sewing machine, and fig. 3 to 5 are perspective views of main parts showing a state before the fabric adjusting apparatus of the sewing machine operates, a state after the fabric is placed, and a fabric adjusting operation state.

In the following description, "up and down", "left and right", and "front and rear" indicated by arrow symbols in fig. 2 are used. Here, "front" is a side close to a sewing operator, "rear" is a side far from the sewing operator, and "left and right" are left and right sides when viewed from the front.

In the above-described double-needle type horizontal tubular double-thread lockstitch sewing machine M, the sewing machine arm 2 and the sewing machine base 3 are extended from the upper and lower portions of the sewing machine column 1 toward the left side direction so as to be substantially parallel to each other. Inside the arm 2 of the sewing machine are mounted: a main shaft of a sewing machine, a needle driving mechanism for reciprocating two right and left needles 4 and 4 (see fig. 2) arranged in parallel in a direction substantially orthogonal to a sewing advancing direction Y in the vertical direction, a presser foot 5, a presser foot lifting/lowering driving mechanism for lifting/lowering the presser foot 5 in the vertical direction, and a power transmission mechanism for the above driving mechanisms are well known, and therefore, the illustration and detailed description thereof are omitted.

A needle plate 6 for guiding the fabric to be conveyed in the sewing direction Y is fixed to the upper surface portion of the base portion 3 of the sewing machine, and a needle drop portion as a needle drop position is formed in the needle plate 6. The sewing machine bed part 3 below the needle plate 6 is provided with: a fabric lower conveying feed dog which intermittently and forcibly transfers the fabric W placed on the needle plate 6 in the sewing advancing direction Y; a looper which is capable of advancing and retreating in a left-right direction substantially orthogonal to the vertical reciprocating path of the needles 4, 4 so as to hold a looper thread, and which grips two needle thread loops formed by the needles 4, 4 under the needle plate 6 during the advancing operation; and a thread cutting device, etc. Here, since the structures, operations, and the like of the feed dog for feeding the fabric under, the looper, the thread cutting device, and the advancing and retreating operation mechanism of the looper are well known, the drawings and detailed description thereof are omitted.

In the horizontal tubular double-thread lockstitch sewing machine M, a fabric turn-back guide device 7 is provided as a fabric end edge guide device at a position (front position) on the upstream side in the sewing traveling direction Y from the needle fall position of the needle plate 6. As shown in fig. 2, the fabric folding guide device 7 includes a guide plate 71 disposed in front of the needle drop portion and a regulation body 72 bent in a substantially japanese hiragana "つ" shape in a front view, folds back one end side edge portion of the fabric W (see fig. 4 and 5) conveyed toward the needle drop position downward by a predetermined width, folds the lower side of the remaining fabric, and guides the conveyance movement toward the sewing portion including the machine needles 4 and 4, the fabric presser foot 5, the needle plate 6, and the like by bringing the edge of the folded-back portion into sliding contact with the curved inner surface of the regulation body 72.

The fabric folding guide device 7 is provided with a plurality of air pipes 73 for introducing high-pressure air from an air supply source, not shown, arranged in parallel in the front-rear direction. The high-pressure air supplied to the air pipe 73 located at the front position is ejected in the left direction in front of the guide plate 71 and the fixed member 72, and the ejected high-pressure air is ejected to the edge portion of the fabric W at the one end side, thereby turning the edge portion of the fabric W downward and assisting the introduction thereof between the guide plate 71 and the fixed member 72.

The high-pressure air supplied to the remaining air pipe 73 is ejected along the lower surface of the guide plate 71 inside the positioning body 72, and functions as follows: the end edge of the fabric W overlapping the lower surface of the guide plate 71 is moved leftward by applying a force, and the remaining fabric is overlapped with the width corresponding to the length of the guide plate 71, so that the fabric W overlapping with a certain width is conveyed to the needle drop position and sewn.

In the horizontal tubular double-thread lockstitch sewing machine M, a fabric guide 8 is provided at a position (front position) on the upstream side in the sewing direction Y from the fabric turn-back guide 7, and the fabric guide 8 guides the conveyance movement of the one end side of the fabric W toward the fabric turn-back guide 7. The fabric guide 8 is provided with a curl correcting device 9, and the curl correcting device 9 corrects the curl generated at the end edge of the one end of the fabric W before the fabric W is introduced into the fabric return guide 7.

As shown in fig. 2, the fabric guide 8 includes a support plate 82 supported by two support rods 81, and

fabric holders

83, 84, 85 attached to the support plate 82. The

support rods

81, 81 extend in the left-right direction in front of the base unit 3 of the sewing machine and are configured to be slidable in the extending direction. The support plate 82 is a flat plate attached to the left end portions of the

support rods

81, 81 in a posture perpendicular to the support rods 81, and is configured to be adjustable in position in the left-right direction in accordance with the sliding movement of the

support rods

81, 81. The

fabric support

83, 84, 85 is composed of a circular tube or rod member bent in a shape of approximately japanese hiragana "つ" and is attached to the left side surface of the support plate 82 in such a manner that the bent portion of the tip end extends to the left.

The fabric holder 83 is disposed along a lower edge of the support plate 82 inclined downward from the front. The fabric holder 84 is narrower and shorter than the fabric holder 83, and is disposed so as to be accommodated inside at a position adjacent to the upper side of the fabric holder 83. The fabric holder 85 is wider and longer than the fabric holder 83, and is disposed apart from the fabric holder 83 forward and upward. The upper portion 85a of the fabric holder 85 is formed in an inclined posture so as to be positioned rearward as it goes to the right.

A plurality of air discharge nozzles (not shown) are supported in parallel in the front-rear direction near the upper end of the support plate 82. These air discharge nozzles are connected to an air supply source, not shown, via air pipes 91, and discharge air supplied from the respective air pipes 91 from the distal ends of the air discharge nozzles toward the base of the air receiving plate 92, thereby correcting the curl generated in the edge portion of the one end side of the fabric W before introduction into the fabric turn-back guide device 7, thereby constituting the curl correction device 9.

A fabric end edge position detector 10 for detecting the position of one end edge of the fabric W is disposed below the fabric guide 8. The fabric edge position detector 10 includes two

optical sensors

10A and 10B arranged at an interval in the left-right direction orthogonal to the sewing direction. The two

photosensors

10A and 10B include a light emitting portion and a light receiving portion which are arranged to face each other in the front-rear direction via a movement path which is guided by the fabric guide portion 8 and which is directed toward the edge on the one end side of the fabric W conveyed by the fabric folding-back guide device 7. As shown in fig. 2, the two

optical sensors

10A and 10B are supported at a position below the fabric holder 85 by a pair of upper and

lower support pieces

12 and 12 attached to the support member 11 fixed to the lower support rod 81 of the

support rods

81 and 81.

The double-needle double-thread lockstitch sewing machine M as the sewing machine main body having the above-described structure is provided with a material adjusting device H which is separate from the sewing machine M. The fabric adjusting device H attached to the sewing machine M includes: a fabric other end holding member 13 which is disposed at a position on an upstream side in a sewing advancing direction Y from a needle drop portion of a needle plate 6 of the sewing machine M and at a position spaced laterally outward from the sewing machine M in a direction substantially orthogonal to the sewing advancing direction Y, and which is capable of holding a fabric W sewn by the sewing machine M on a side of the other end portion opposite to the one end portion; a fabric intermediate portion holder 14 which is disposed between the fabric other end holder 13 and the fabric guide 8 and holds an intermediate portion of the fabric W; a fabric end edge position adjusting mechanism 15 configured to drive the fabric intermediate portion holder 14 to reciprocate in the vertical direction such that the end edge position on the one end portion side of the fabric W is adjusted in the horizontal direction orthogonal to the sewing advancing direction Y; and a fixing stand 16 to which the other-end-of-fabric-holding piece 13, the intermediate-fabric-holding piece 14, and the fabric edge position adjusting mechanism 15 are attached.

As shown in fig. 1 and 3, the fabric other end holding member 13 includes: a fixed grip piece 13A fixed to the lower end of the upper and lower frame portions 16A of the fixed frame 16, and a movable grip piece 13B driven by the expansion and contraction operation of the air cylinder 17 to be openable and closable with respect to the fixed grip piece 13A. The other end gripper 13 for the fabric including the pair of

gripping pieces

13A and 13B is configured to release the gripping of the other end side of the fabric W by switching an electromagnetic valve that receives a sewing end signal of the sewing machine M and controls the supply of gas to the cylinder 17 to one direction to contract the cylinder 17, to drive the movable gripping piece 13B to perform an opening operation with respect to the fixed gripping piece 13A, and to drive the movable gripping piece 13B to perform a closing operation with respect to the fixed gripping piece 13A by switching the electromagnetic valve to the opposite direction to extend the cylinder 17 by pressing an operation piece of a limit switch 18 attached to the upper and lower frame portions 16A, to grip the other end of the fabric.

The fabric intermediate portion holder 14 includes: a drum roller 14A for supporting and holding the intermediate portion of the fabric W from below, and a fixed mandrel 14B for rotatably supporting the roller 14A.

The fabric end edge position adjusting mechanism 15 is configured such that the fabric intermediate portion holder 14 can be driven to reciprocate in the vertical direction (an example of a specific direction) along a vertical guide bar 21 by a rack 19 and a stepping motor 20 that rotationally drives a pinion (not shown) that meshes with the rack 19, wherein the rack 19 supports the fabric intermediate portion holder 14 so as to be stretched in parallel with the upper and lower frame portions 16A of the fixing frame 16 via a fixing member 18 that fixes a vertical bar portion 14C extending upward from one end portion of the fixing stem 14B.

The fabric edge position adjusting mechanism 15 includes the following control units: the fabric intermediate holder 14 is driven by the rack 19 and the stepping motor 20 to move downward in response to a detection operation for detecting that one end edge of the fabric W guided by the fabric guide 8 toward the fabric return guide 7 is deviated from the light receiving and projecting range of the left photosensor 10A of the two

photosensors

10A, 10B of the fabric end edge position detector 10, and the fabric intermediate holder 14 is driven by the rack 19 and the stepping motor 20 to move upward in response to a detection operation for detecting that one end edge of the fabric W exceeds the light receiving and projecting range of the right photosensor 10B of the fabric end edge position detector 10.

In the fabric adjusting device H, a rectangular-pillar-shaped sponge member 22 as an example of an elastic member is erected along the upper and lower frame portions 16A of the fixed frame 16, and the upper and lower frame portions 16A are located on the side of the vertical reciprocating movement path of the fabric intermediate holder 14. When the fabric intermediate portion holder 14 is driven by the fabric end edge position adjustment mechanism 15 to reciprocate in the vertical direction, the sponge member 22 is configured such that the fabric portion Wc located between the intermediate portion of the fabric W held by the fabric intermediate portion holder 14 and the other end portion Wb of the fabric W held by the fabric other end gripper 13 slides in contact with the surface of the sponge member 22, and the fabric portion Wc moves in the vertical direction to freely rotate the roller 14A in the forward and backward directions.

Next, a sewing operation of performing hemming sewing of a round material web W such as an end portion of a T-shirt using the double-needle type horizontal tubular double-thread lockstitch sewing machine M and the web adjusting device H according to the first embodiment configured as described above will be described with reference to fig. 3 to 5.

Before starting sewing, the fabric intermediate portion holder 14 is positioned at the lowermost portion of the vertical reciprocating path as shown in fig. 3 by the stepping motor 20 and the rack 19 of the fabric end edge position adjusting mechanism 15. Accordingly, when the fabric W is placed in the fabric adjusting device H and the horizontal double-line lockstitch sewing machine M, the fabric intermediate portion holder 14 does not interfere with the fabric W, and the placing operation can be easily performed.

Then, in a state where the material presser foot 5 is driven to be raised and the movable grip piece 13B of the material other end grip 13 of the material adjusting device H is driven to be opened with respect to the fixed grip piece 13A, as shown in fig. 4, at the end portion at one end of the round material W, the end edge portion is guided into the material returning guide device 7 through the material guide portion 8, the end edge portion at one end of the material W is returned to the back side of the material to be overlapped, the returned material portion (sewing portion) Wa is placed on the needle plate 6, then, the presser foot 5 is driven to be lowered while the other end portion Wb of the round material W is inserted between the fixed grip piece 13A and the movable grip piece 13B of the material other end grip 13 of the material adjusting device H, and the operation piece of the limit switch 18 is manually pressed, the movable grip piece 13B is thereby driven to open with respect to the fixed grip piece 13A by the extension operation of the air cylinder 17, and the other end portion Wb of the round material W is gripped.

At this time, the middle portion of the fabric W is supported and held by the roller 14A of the fabric middle holder 14 as shown in fig. 4, and the horizontal double-line lockstitch sewing machine M is rotated in this state, whereby the sewing portion Wa of the round fabric W, which is overlapped by being supported and conveyed by the

fabric holders

83, 84, 85 of the fabric guide 8 and introduced between the guide plate 71 and the gauge body 72 of the fabric turn-back guide 7 with one end side end edge portion turned back to the back side of the fabric, is intermittently and forcibly transferred in the sewing advancing direction Y by the feed dog for fabric lower conveyance acting on the lower surface of the sewing portion Wa and the presser foot 5 acting on the upper surface thereof, and the double-line lockstitch is formed over the entire circumference of the sewing portion Wa of the round fabric W (overlapped fabric portion) by a series of sewing operations such as the raising and lowering operation of the left and right needles 4, 4 accompanying the rotation of the sewing machine M, and the advancing and retracting operation of the looper And (5) hemming and sewing.

In the hemming sewing, the position of the end edge of the one end of the round cloth W conveyed toward the cloth folding guide 7 is supported by the

cloth holders

83, 84, 85 of the cloth guide 8, and may be displaced in the left-right direction by an external force such as the weight of the middle portion of the cloth between the sewing machine M and the cloth adjusting device H. In particular, in the case of a fabric having a curved end edge at one end of the fabric W, the displacement in the left-right direction becomes significant.

According to the fabric adjusting apparatus H of the sewing machine according to the first embodiment, the one end edge position of the round fabric W is always monitored by the two

optical sensors

10A and 10B of the fabric end edge position detector 10, and the fabric end edge position adjusting mechanism 15 is controlled to operate as follows: the fabric intermediate portion holder 14 is driven to move downward by the rack 19 and the stepping motor 20 in response to a detection operation of detecting that the one end side edge We of the fabric W conveyed toward the fabric turn-back guide 7 is displaced leftward and deviates from the light receiving and projecting range of the left photosensor 10A, and the fabric intermediate portion holder 14 is driven to move upward by the rack 19 and the stepping motor 20 in response to a detection operation of detecting that the one end side edge We of the fabric W is displaced rightward and exceeds the light receiving and projecting range of the right photosensor 10B.

As described above, by driving the fabric intermediate portion holder 14 to move in the vertical direction u-d as shown in fig. 5 in accordance with the displacement of the one end portion side edge position of the fabric W in the left-right direction, even if the sewing object is a stretchable fabric or a fabric having a curved one end portion side edge, the position of the one end portion side edge We of the fabric W can be automatically adjusted to a predetermined position over the entire length of the edge, and therefore, the folded width or the overlapped portion of the one end portion side of the fabric can be maintained within a predetermined range, and proper and satisfactory hemming sewing can be performed at all times.

In particular, in the case of the first embodiment, when the roller 14A of the fabric intermediate portion holder 14 is driven by the fabric end edge position adjusting mechanism 15 to reciprocate in the vertical direction, the fabric portion Wc (see fig. 5) located between the intermediate portion of the fabric W supported and held by the roller 14A and the other end portion Wb of the fabric W held by the fabric other end gripper 13 is brought into sliding contact with the sponge member 22 erected along the vertical reciprocating drive movement path side of the fabric intermediate portion holder 14 and is subjected to friction, and thus the fabric portion Wc is forcibly moved in the vertical direction. Since the roller 14A rotates in the forward and backward directions with respect to the fixed mandrel 14B as the fabric portion Wc moves up and down, the function of automatically adjusting the one end side edge We of the fabric W to a predetermined position over the entire length of the edge can be performed reliably and with good responsiveness regardless of the type of the fabric W or the like.

In the first embodiment, the fabric intermediate portion holder 14 that can drive and hold the intermediate portion of the fabric W by the fabric edge position adjustment mechanism 15 is configured to reciprocate in the vertical direction, but a second embodiment having the following configuration may be employed as shown in fig. 6: the other-end fabric gripper 13 gripping the other end portion Wb of the fabric W can be driven to reciprocate in the vertical direction u-d by the fabric edge position adjustment mechanism 15 including the rack and the stepping motor (not shown) similar to those described in the first embodiment.

In the fabric adjusting device of the sewing machine according to the second embodiment, as well as in the first embodiment, by detecting the displacement of the one end side edge position of the fabric W in the left-right direction by the two

photosensors

10A, 10B of the fabric end edge position detector 10, the fabric other end gripper 13 is driven to move in the vertical direction u-d, whereby even if the sewing object is a fabric having elasticity or a fabric having a curved one end side edge, the position of the one end side edge We of the fabric W can be automatically adjusted to a predetermined position over the entire length of the edge, and therefore, the folded width or the overlapped portion of the one end side of the fabric can be maintained within a predetermined range, and proper and satisfactory hemming sewing can be always performed.

Further, in the fabric adjusting apparatus of the sewing machine according to the second embodiment, the stepping motor 23 which is synchronized with the sewing operation of the sewing machine M is configured to drive the fabric other end gripper 13 to rotate around the vertical or substantially vertical axis s, so that it is possible to avoid as much as possible an excessive load due to the weight of the fabric or the torsion of the fabric intermediate portion to be applied to the end portion which is the sewing portion at the time of a predetermined sewing operation, and it is possible to perform the hemming sewing more favorably.

In the first and second embodiments of the present invention, the reciprocating direction in which the fabric intermediate portion holder 14 or the fabric other end gripper 13 is driven by the fabric end edge position adjusting mechanism 15 is set to the vertical direction, but the reciprocating direction may be the horizontal direction or the vertical/horizontal direction, and a predetermined fabric end edge position adjusting function can be realized in the case where reciprocating movement is performed in either direction.

The sewing machine with the fabric adjusting device H is not limited to the above-described multi-needle horizontal tubular double-lock stitch sewing machine, and may be a lockstitch sewing machine in which a stitch of a lockstitch is formed on the entire circumference of the overlapping portion of one end side of the round fabric.

In the above embodiments, the configuration in which the fabric other end gripper 13 includes the fixed gripping piece 13A and the movable gripping piece 13B that is driven to open and close relative to the fixed gripping piece 13A has been described, but the pair of gripping pieces may be driven to open and close by swinging apart and close to each other, or may be a pair of spring-type configurations.

Claims

1. A fabric adjusting device of a sewing machine is provided with:

a sewing machine body, comprising: a needle plate for guiding the feeding of the fabric in the sewing advancing direction; a needle configured to be movable up and down so as to pass through a needle drop portion formed in the needle plate; a fabric presser foot capable of lifting; a fabric end edge guide device which is arranged at a position closer to the upstream side of the needle drop part in the sewing advancing direction, and is in sliding contact with one end edge of the fabric to guide the movement of the end edge in the sewing advancing direction; and a fabric guide section which is disposed at a position upstream of the fabric end guide device in a sewing direction and guides a conveying movement of the fabric end side to the fabric end edge guide device; and

a fabric other end holding member which is arranged on the upstream side of the needle drop part in the sewing advancing direction and at a position separated from the needle drop part in the direction orthogonal to the sewing advancing direction and towards the transverse outer side of the sewing machine main body, and can hold the other end side of the fabric,

the fabric adjusting device of the sewing machine is characterized by comprising the following components:

a fabric end edge position adjusting mechanism configured to be capable of driving the fabric other end holding piece or a fabric middle holding piece arranged between the fabric other end holding piece and the fabric guide part to hold a fabric middle part to reciprocate along a specific direction so that an end edge position of one end part side of the fabric is subjected to position adjustment in a direction orthogonal to a sewing advancing direction;

a fabric edge position detector disposed below the fabric guide portion and detecting a position of an edge of one end of the fabric; and

and a control unit that drives the fabric edge position adjustment mechanism to reciprocate in the specific direction based on a detection result of the fabric edge position by the fabric edge position detector so that the edge position on the one end portion side of the fabric is adjusted to a predetermined position.

2. A fabric adjusting device of a sewing machine according to claim 1, characterized in that:

the sewing machine is used for hemming and sewing,

the sewing machine main body is provided with:

the needle plate is used for placing an overlapped part formed by turning back one end part of the fabric and guiding the overlapped part to convey in the sewing advancing direction;

the needle; and

the presser foot.

3. A fabric adjusting device of a sewing machine according to claim 1, characterized in that:

the fabric guide is provided with a curl correcting device that corrects a curl generated at the one end side edge of the fabric before the one end side edge of the fabric is introduced into the fabric end edge guide.

4. A fabric adjusting device of a sewing machine according to claim 1, characterized in that:

the fabric end edge position adjusting mechanism is configured to drive the fabric other end gripper or the fabric intermediate holder to reciprocate in any specific direction of a vertical direction, a horizontal direction orthogonal to a sewing traveling direction, and a vertical/horizontal tilting direction based on a detection result of the fabric end edge position detector on the fabric end edge position.

5. A fabric adjusting device of a sewing machine according to claim 1, characterized in that:

the fabric end edge position detectors are arranged in two spaced-apart relation in a left-right direction orthogonal to a sewing direction of travel, and the fabric end edge position adjustment mechanism is driven to move in one of the specific directions in accordance with a detection operation of one of the fabric end edge position detectors, and the fabric end edge position adjustment mechanism is driven to move in the other of the specific directions in accordance with a detection operation of the other fabric end edge position detector.

6. A fabric adjusting device of a sewing machine according to claim 1, characterized in that:

the other-end fabric gripper is configured to be capable of being driven to rotate around a vertical or substantially vertical axis by a motor that is synchronously linked with the sewing operation of the sewing machine body.

7. A fabric adjusting device of a sewing machine according to claim 1, characterized in that:

the fabric intermediate portion holder driven by the fabric end edge position adjustment mechanism to reciprocate in the vertical direction includes: the fabric cutting device includes a roller for supporting and holding an intermediate portion of fabric from below, and a fixed mandrel for rotatably supporting the roller.

8. The fabric adjusting apparatus of a sewing machine according to claim 7, characterized in that:

the roller of the fabric intermediate portion holder is configured such that, when the fabric intermediate portion holder is driven by the fabric end edge position adjusting mechanism to reciprocate in the vertical direction, the fabric intermediate portion held by the roller is brought into sliding contact with an elastic member erected along the vertical reciprocating drive movement path side of the fabric intermediate portion holder, and the roller is rotated in the forward and backward directions by the fabric intermediate portion moving in the vertical direction.