KR20040050880A - Device for holding the upper threads in the sewing machine - Google Patents

Abstract

PURPOSE: An upper yarn fixing device is characterized by not staining upper yarn with a middle shuttle, preventing the upper yarn from inserting, shortening length of remained yarn and applying to a cylinder bed sewing machine. CONSTITUTION: An upper yarn fixing device(10) comprises: (a hold device,20) a fixing part fixing an end of upper yarn; a hold part transferred between a hold position and an open position relative to the fixing part to hold-open the end of the upper yarn; a first transfer position set on a up-and-down path of a sawing needle(104); a second transfer position transferred to a stand protecting part side(102) of a sewing machine from the up-and-down path of the sawing needle; a third transfer position transferred to the stand protecting part side(102) from the up-and-down path; a transferring device(40) transferring the hold device(20) from the first transfer position to the second transfer position in time that sewing is started and transferring the hold device(20) from the second transfer position to the third transfer position for falling a needle; and a relational work device(60).

Description

DEVICE FOR HOLDING THE UPPER THREADS IN THE SEWING MACHINE}

The present invention relates to the upper thread fixing device of the sewing machine, and relates to the upper thread fixing device of the sewing machine for fixing the end of the upper thread until forming a predetermined number of seams when starting sewing.

In sewing work with a normal sewing machine, the sewing thread is started with the thread of the sewing needle and the upper thread inserted into the hole free of the tip. When the needle descends, the thread tip enters or falls out of the thread through hole. There is a problem such as not being formed. Therefore, when starting to sew, it is necessary to make a sufficient length from the through-hole to the front end of the thread, so that after the completion of seam, the long end from the cloth to the front end of the seam protrudes. Because of the lack of aesthetics, it was necessary to reduce the value of the product or to cut the thread by hand after sewing.

For this reason, the end of the upper thread is pinched from the inside of the needle plate from the first seam at the start of sewing to the needle drop of a predetermined number of needles so as to form a seam at the start of sewing while shortening the length of the upper thread remaining inside the fabric at the start of sewing. The upper thread fixing device is used (for example, Japanese Patent No. 2671478 and Japanese Patent Laid-Open No. 2000-325683).

Japanese Patent No. 2671478 discloses an upper thread for moving a thread holder having a perforated hole to a capturing position for capturing an end of a sewing needle, a fixed position for fixing the captured upper thread end, and a release position for opening the fixed upper thread end. A fixing device (described in the document as "thread grabbing device") is disclosed. In the upper thread fixing device, the thread noise is placed on the shanghai east path of the needle so that the sewing needle penetrates the through hole of the thread noise at the capture position, and the thread noise is fixed along the north axis direction after the sewing needle of the first seam is raised. Evacuate to position. And the thread end part which passes through a permeation hole in a fixed position is clamped between the clamping surface arrange | positioned at the needle plate and the upper surface of a thread noise. After the predetermined number of seams are formed, the thread noise is separated from the needle plate, and the upper thread end portion between the needle plate and the thread noise is released.

Japanese Unexamined Patent Publication No. 2000-325683 includes a thread catching plate and a thread catching wire supported to be movable along its periphery, and unwinds the thread catching wire forward of the front end of the catching plate to form a loop. An upper thread fixing device (described in the document as "a bird cage preventive device") that sandwiches the upper thread end inserted into the loop by the drawing and the thread catching wire is disclosed.

In the upper thread fixing device, the thread catching wire and the thread catching plate are positioned so that the loop is located on the shanghai-dong path of the sewing needle while the loop is formed, and the thread catching wire is inserted after the sewing needle of the first seam is raised. Secure the upper threaded end. The upper thread end portion is pulled to the loop side by the tensile force of the balance, and the length to the upper thread end portion is shortened, and the upper thread end is pulled out by the conveyance of the fabric by the predetermined number of seams to be pulled out between the wire and the thread catching plate. The thread catching wire and the thread catching plate are then retracted to the retracted position.

However, in the conventional upper thread fixing device described in Japanese Patent Nos. 2671478 and JP 2000-325683 A, the member for pinching the upper thread is disposed at the tip side of the sewing machine bed rather than the shanghai path of the needle. The space in which the upper thread fixing device is arranged on the bed tip side in the bed tip direction than the shanghai path of the needle is also required.

Therefore, it was not possible to arrange such upper thread fixing device in the cylinder bed sewing frame that requires the tip side of the sewing machine bed to be thin, long or short and small.

In addition, when the upper thread fixing device is placed in the bed as disclosed in Japanese Patent No. 2671478, the upper thread touches the race face of the north axis of the north of the center and gets dirty or enters the race face of the north axis of the center of North Korea. To avoid this problem, if the position of the pincer is placed away from the shanghai-dong path of the needle, the pinch of the upper thread end is separated from the shanghai-dong path of the needle. There was concern.

The present invention has been made to improve the problem of the prior art to provide an upper thread fixing device which prevents the upper thread from being soiled or drawn by the middle drum even when the upper thread fixing device is placed in the bed and also shortens the length of the thread remaining. The purpose.

In addition, an object of the present invention is to provide an upper thread fixing device of a sewing machine applicable to a cylinder bed sewing machine while keeping the length of the end side short after fixing the upper thread.

Brief Description of Drawings Fig. 1 is an overall side view of a part cut away showing the outline of a sewing machine.

Fig. 2 is a perspective view showing a major overall configuration of the upper thread fixing device.

3 is an exploded perspective view showing the main configuration of the upper thread fixing device.

4 is a plan view of the upper thread guide plate seen in the U direction in FIG. 6;

5 is a front view of the center drum of the drum mechanism as seen in the X-axis direction.

Fig. 6 is an operation explanatory view of the upper thread fixing device in the case where the clamping means is in the first moving position.

Fig. 7 is an operation explanatory view of the upper thread fixing device when the clamping means is in the first moving position from below;

8 is an operation explanatory view of the upper thread fixing device in a state where the flat part of the fixing part and the clamping part touches the front of the second moving position from the right;

9 is an operation explanatory view of the upper thread fixing device in a state where the flat portion of the fixing portion and the clamping portion touches the front of the second moving position;

Fig. 10 is an operation explanatory view of the upper thread fixing device in the case where the clamping means is in the second moving position from the right.

Fig. 11 is an operation explanatory view of the upper thread fixing device when the clamping means is in the second moving position from below;

12 is an operation explanatory view of the upper thread fixing device when the clamping means is in the third moving position from the right side;

Fig. 13 is an operation explanatory view of the upper thread fixing device when the clamping means is in the third moving position from the bottom;

Fig. 14 is an explanatory view seen from below showing the relationship between the rocking motion of the relative position adjusting link member and the relative position change of the fixing member and the gripping member;

Fig. 15 is a block diagram showing a control system of the sewing machine.

Figure 16 is an operation flowchart of the sewing machine.

Fig. 17 is a perspective view partially cut away of each structure under the needle of the embodiment for explaining the effect of the embodiment;

Fig. 18 is a perspective view partially cut away of each structure under the needle of the comparative example for explaining the effect of the embodiment;

※ Explanation of symbols about main part of drawing ※

10: upper thread fixing device 21: fixing part

22: fixing member 31: gripping portion

32: holding member 40: moving means

60: associated operation means 61: guide plate (guide means)

62: tension spring (tension boosting means) 63: relative positioning link body

64: first contact member 65: second weeding member

100: sewing machine 104: sewing needle

M: The straight line which binds the north side side border of a needle hole, and the upper edge of the north side race surface of the center north

N: Shanghai East Path of Sewing Needle

The invention of the first aspect of the present invention pinches the end of the upper thread inserted into the sewing needle at the start of sewing at the bottom of the needle plate and above the passage path of the pointed end of the middle drum with respect to the sewing needle. Fixing part for fixing the end of the upper thread in the upper thread fixing device of the sewing machine to move the end to a position away from the shanghai path of the sewing needle, and to open the end of the pinched upper thread after a needle drop of a predetermined number of needles; A first moving position positioned on the shanghai east path of the sewing needle, the holding part having a gripping portion relatively moved to a clamping position and an open position with respect to the fixing portion to sandwich the end of the upper thread between the fixing portion; And a second moving position spaced apart from the first moving position to the moving part side of the sewing machine with respect to the shanghai path of the sewing needle, and the second moving position. Gripping means for moving from the same position back to the third moving position spaced apart from the shanghai path of the sewing needle to the moving part side of the sewing machine, and the gripping means from the first moving position to the second moving position at the start of sewing. Moving means for moving from the second moving position to the third moving position after stopping for a needle drop of a predetermined number of needles; and when the gripping means is located at the first moving position, The fixing part is disposed at the position of the inlet side of the sewing machine from the shanghai east path of the sewing needle, and the fixing unit is disposed at a position facing the pinching part with the shanghai east path of the sewing needle interposed therebetween. When moving from the 1st moving position to the 2nd moving position, the said fixed part and the clamping part are moved to the direction approaching each other, and the said upper part At the same time, the gripping portion is moved to the second moving position and the gripping means moves to the third moving position from the second moving position or at the third moving position. And associated operation means for mechanically connecting the gripping portion and the fixing portion to the moving means to isolate the fixing portion and open the sandwiched upper thread end portion.

In the above configuration, the gripping means is positioned in the first moving position, and the gripping portion is disposed on the other side of the fixing portion on the side of the moving portion with the shanghai copper path of the sewing needle interposed therebetween. In this state, the upper thread end is inserted between the fixing part and the clamping part by the lowering and raising of the first seam of the sewing needle.

And in this state, the clamping means is moved to the 2nd moving position spaced apart from a 1st moving position to the sewing machine entrance part side. In this movement, the fixing portion moves toward the gripping portion side, and the gripping portion moves toward the fixing portion side, so that the contacting gripping positions are closer to the shanghai path of the sewing needle than the position of the gripping portion at the first moving position.

Then, the gripping means waits at the place after reaching the second moving position and moves toward the third moving position separated from the moving part side again when a predetermined number of needle drops are performed. At that time, since the fixing portion and the clamping portion are separated by the associated operation means, the upper thread end is released.

In such a configuration, the clamping means moves from the position at which the sewing needle moves up and down toward the mouth of the sewing machine. The gripping means moving toward the moving part of the sewing machine does not need to secure a space for moving the gripping means toward the tip side of the sewing needle of the sewing machine bed. can do.

In this way, when the clamping means is moved from the first moving position to the second moving position on the sewing machine moving part side and the upper thread is clamped during this movement, only the fixing part moves toward the clamping part located on the sewing machine moving part side, In order to shorten the length of the upper thread end remaining in Cheonan, it is necessary to place the clamping member close to the shanghai east path of the sewing needle, but in this case, the upper seal loop is held by the pointed end of the middle drum. The expansion of the upper thread by the upper thread guide plate, which prevents contact with the race face, is prevented by this clamping part, and the upper thread touches the race face of the north axis in the north of the center and becomes dirty or enters the race face of the north axis of the center in the north. Occurs. On the other hand, in order to avoid such a problem, if the position of the pincer is placed away from the shanghai east path of the needle, the pinching part of the upper thread end is separated from the shanghai east path of the needle, so that the length of the thread remaining in the Cheonan side will be shortened. The problem arises that it cannot.

However, in the invention of claim 1, when the upper thread end is pinched, the pinch part also moves toward the fixing part, so when the pointed tip of the north catches the upper seal, the pinch part is placed a predetermined distance away from the shanghai east route of the needle. After the needle is pulled out between the clamping part and the fixing part, the pinching part may be moved to a pinching position near the shanghai east path of the sewing needle to pinch the upper thread. Therefore, it is possible to shorten the length of thread cutting remaining on the inner side of the fabric without disturbing the upper thread guide plate from extending the upper thread.

The invention of claim 2 has the same configuration as that of the invention of claim 1, and the associated operation means includes a needle hole arranged on the needle plate to arrange the distal end of the gripping portion when the gripping means is located at the first moving position. The upper thread end by the fixing part and the clamping part when the clamping means is located at the second moving position from the first moving position to the north axis side rather than a straight line which ties the north side side border of the upper end edge of the race face of the north axis side of the north. The position where the pinching of the needle is held is located near the Shanghai-dong path of the sewing needle.

In the above configuration, the gripping portion exhibits the same operation as the invention of claim 1 and at the same time, when the gripping means is in the first moving position, the gripping portion binds the north edge side edge of the needle hole with the upper edge of the north side race surface of the central north side. It is located on the north axis side rather than a straight line, and this arrangement is arranged so as not to invade the shanghai east path side of the sewing needle. The straight line connecting the north side edge of the needle hole and the top edge of the north side race surface of the central north represents the boundary of the upper thread passage, and the upper side thread loop is formed by the upper thread guide plate. The interference between the upper raceway and the upper raceway of the central shaft on the north side can be effectively avoided by reliably preventing the expansion of the core.

The invention of Claims 3 and 4 has the same configuration as the invention of Claims 1 or 2, and the gripping means has a fixing member having a fixing part and a gripping member having a gripping part, and the related operation means is a gripping member. And guide means for supporting the fixing member so as to reciprocate in a direction along the north axis, a tension biasing means for providing constant tension between the clamping member and the fixing member in a direction in which the clamping portion and the fixing portion approach each other, and It is possible to fold the gripping portion and the fixing portion according to the posture change by the relative position control linkage which is connected to each of the gripping member and the fixing member, and at the same time, the moving force of the gripping means by the moving means is input to each moving position. And a first contact which swings in a direction in which the gripping portion and the fixing portion are separated by contacting the relative position adjusting link member when the gripping means is in the first moving position. And the second contact member which touches the relative position adjusting link member when the clamping means is in the third moving position and swings in the direction in which the clamping portion and the fixing portion are separated from each other. The rotation engaging portion of the holding member and the rotating engaging portion of the holding member and the moving means positioned therebetween are disposed so that the first contact member is connected to the rotating engaging portion of the holding member and the moving means. It takes the structure which abuts in the position between rotational coupling parts.

In the above configuration, the same operation as that of the invention of claim 1 or 2 and at the same time, when the clamping means is disposed in the first moving position, the relative position adjusting link member is oscillated by the first contact member with its contact position as the point. Space the fixing part and the clamping part against the taxable means.

Then, when moving to the second moving position, the contact state of the first contact member with respect to the relative position control link member is released according to the movement. Therefore, the relative position adjustment link member swings in the direction returned by the tension biasing means with the point of contact with the first contact member as a point. In this way, the relative position control link member swings between the rotational coupling portion with the holding member and the rotational coupling portion with the holding member as a point, and thus the fixing portion and the holding portion are moved in a direction approaching each other. For this reason, the upper thread end part is fixed when the clamping means moves to the second moving position.

In addition, since the second contact member swings the relative position adjusting link member with the approach of the third movement position when moving from the second movement position to the third movement position, the fixing part and the clamping part which are in the pinched state are spaced apart from each other. The end is open.

(Embodiment)

(Overall schematic composition of sewing frame)

The sewing machine 100 to which the upper thread fixing device 10 according to the embodiment of the present invention will be described with reference to FIGS. 1 to 18.

The sewing machine 100 has a sewing machine bed 101, the outline of which is located at the bottom, a sewing machine moving part 102 raised upward from one end of the sewing machine bed 101, and a sewing machine moving part 102. It consists of a sewing machine arm 103 which is spoken to follow the sewing machine bed 101 from above. In addition, the sewing machine bed 101 corresponds to a so-called cylinder (cylindrical) bed whose tip portion is formed in a substantially cylindrical shape and whose width in the X-axis direction described later is narrower than that of other portions.

In addition, in describing the configuration of the sewing machine 100, the shank east direction of the sewing needle 104, which will be described later, is set as the Z-axis direction, and the longitudinal directions of the sewing machine bed 101 and the sewing machine arm 103 are perpendicular to the direction. It is set as the Y-axis direction, and the direction orthogonal to both a Z-axis direction and a Y-axis direction is made into the X-axis direction. In addition, when the sewing machine 100 is installed on the horizontal plane, the + side in the Z-axis direction becomes up and down, and the + side in the X-axis direction is right, the-side is left, and the + side in the Y direction. Expresses the front and back of the-side.

The sewing machine 100 is disposed at the distal end of the sewing machine arm 103 and is disposed on the sewing needle 104 reciprocating in the vertical direction by the sewing machine motor 105, and the upper part of the sewing machine arm 103, and the sewing needle 104. And an upper thread supply source (not shown) for supplying the upper thread to the upper thread), and a real state device 106 for pinching the upper thread with a predetermined load between the upper thread supply source and the sewing needle 104 to generate a resistance to movement in the conveying direction. A balancer for raising the upper thread by the balance 107 at a predetermined timing between the thread state device 106 and the sewing needle 104, and the upper surface 101A of the sewing machine bed 101, The needle plate 108 having a needle hole 108a for inserting the tip of the sewing needle 104 is disposed, and is disposed below the needle plate 108 in the sewing machine bed 101, and the lowered sewing needle 104 is disposed. Drum mechanism 120 for inserting the lower thread into the loop at the same time as the upper It is disposed in the sewing bed 101 and the upper thread fixing device 10 for fixing the upper thread end portion when the first seam of the sewing needle 104 rises between the needle plate 108 and the drum mechanism 120. And a thread cutting device (not shown) for cutting the upper thread and the lower thread later, and an operation control means 80 for performing the operation control of each of the above configurations.

The sewing needle 104 has a thread through hole formed at an upper end of the sewing needle 104 (lower end), and the upper thread is inserted into the thread through hole. In addition, the sewing thread 104 is supported at the lower end of the needle bar 104a, and the needle bar 104a is provided by converting the rotational driving force from the sewing machine motor 105 into a vertical reciprocating driving force by a crank mechanism (not shown). Reciprocating up and down is performed in cycles. The sewing machine motor 105 is provided with an encoder 109 for detecting the rotation angle, and the output shaft of the current sewing machine motor 105 is 0 ° when the sewing needle 104 is at the top dead center position. It outputs to the motion control means 80 which one of the angles is in the angle position.

The balance 107 is provided with an upper thread insertion hole (not shown), and the upper thread is inserted into the upper and lower threads so that the upper thread inserted into the sewing needle 104 is pulled up. The balance apparatus moves the balance 107 in the same cycle as the sewing needle 104, but the timing of the balance 107 near the top dead center is set to be somewhat later than the top dead center of the sewing needle.

As shown in Fig. 6, the drum mechanism 120 rotates in half the reciprocation and freely picks the drum 122 and the center drum 122 by capturing the loop of the upper thread by the pointed tip 12 protruding along the rotation circumferential direction. The large drum 123 supporting to rotate, the upper thread guide plate 124 disposed on the upper portion of the large drum 123, and parallel to the sewing machine bed in the longitudinal direction toward the large drum 123 at the mouth of the sewing machine It has a north shaft 125 which imparts reciprocating half-rotation driving force to the center drum 122 through the driver which does not have.

The center drum 122 has a rail-shaped protruding structure 126 formed on its outer circumference so as to repeatedly perform a half turn, and the race surface 127 which slides in contact with the support groove 123a of the drum 123 on both sides thereof. 128). The pointed end 121 is formed at the end of the rail-shaped protrusion structure 126, and the sewing needle penetrates from the guide hole of the upper thread guide plate 124 by one half rotation operation of the central drum 122. Hold the loop of the upper thread by passing right next to the thread and hole in 104). For this reason, the pointed tip 121 is formed in the shape of the tip of the tip in the direction (L) along the center line of rotation of the center drum 122, while the pointed tip 121 and the protrusion structure 126 is sewing needle 104 It is arranged in the other direction (R) side along the rotation center line with respect to the shanghai east route (N).

Moreover, the north shaft 125 is located in the R side with respect to the center north 122 (the next direction (R) side is made into the north axis side), and although it is not directly connected to the center north 122, it is provided in the center north 122 The driving force of the reciprocating half rotation is cut | disconnected to the center north 122 through the driver which performs reciprocating half rotation together.

The north shaft 125 of the drum mechanism 120 is disposed in parallel in the Y-axis direction and positioned on one side in the Y-axis direction with respect to the central north 121, and at the same time, the reciprocating half-rotation driving force is applied in this direction. In addition, the north shaft 125 is a configuration in which the driving force branched from the sewing machine motor 105 is converted into a reciprocating rotation, and is transmitted, with a predetermined phase difference for the up and down reciprocating operation of the sewing needle 104 and the reciprocating half rotation operation of the central drum 122. Motivation can be achieved.

The upper thread guide plate 124 is a plate-shaped member for preventing contact or winding of the race face 127 and 128 of the middle drum 122 of the upper thread, as viewed from the upper side (arrow U direction) of FIG. 6. A guide hole 124a having a shape as shown in FIG. 4 is disposed, and a thread dividing part 124b for unfolding the upper seal loop held by the pointed end 121 of the middle drum 122 is disposed at the almost right center portion of the guide hole 124a. It is deployed. 5 and chamber of Figure needle thread loop captured by the pointed end 121 for rotation in the arrow S direction, and 17 is the sewing needle to guard against the pointed end 121 by a chamber dividing portion (124b) side of (N _F) It is largely separated back and forth by the yarn N _B on the cloth side, and the contact or winding of both race surfaces 127 and 128 of the middle north 122 is prevented.

(Composition of Upper Thread Fixture)

The upper thread fixing device 10 is disposed in the sewing machine bed 101.

The upper thread fixing device 10 is fixed to the fixing portion 21 for fixing the end of the upper thread and the holding portion 21 is relatively moved to the pinching position and the open position to pinch the end of the upper thread between the fixing portion 21. A gripping means 20 having a gripping portion 31, a first moving position in which the gripping means 20 is positioned on the shanghai-dong path N (see FIG. 6) of the sewing needle 104; Line unit value of the sewing needle 104 at the bottom dead center from the distal position of the sewing needle 104 of the sewing needle 104 from the first moving position (parallel in the Z-axis direction and at the top dead center of the sewing needle 104). To the second moving position separated from the rear (the sewing frame moving part 102 side) with respect to the binding path), and to the third moving position further away from the second moving position (the sewing frame moving part 102 side)). At the same time, the needle is moved from the first moving position to the second moving position at the start of sewing, and the needle drop movement of the predetermined number of needles Moving means 40 for moving the second moving position from the second moving position to the third moving position after stopping, and holding the clamping portion 31 when the holding means 20 is positioned at the first moving position. At the same time, the fixing part 21 is disposed at the position facing the pinching part 31 with the shanghai-dong path N of the sewing needle 104 interposed therebetween. When the clamping means 20 moves from the first moving position to the second moving position, both the fixing part 21 and the clamping part 31 are moved in a direction approaching each other, and the upper thread end is clamped. The clamping portion 20 is moved to the second moving position, and the clamping portion 31 is fixed to the clamping portion 31 when the clamping means 20 moves from the second moving position to the third moving position or in the third moving position. The holding part 31 and the fixing part 21 are mechanically moved by the movement means 20 so as to open the end portions of the upper thread which are separated from each other. And a relevant operating means (60) for interlocking with. The following sections will be described in detail.

(Spinning means of upper thread fixing device)

In FIGS. 2 and 3, the clamping means 20 supported on the bottom surface of the bed top surface 101A as described above is a clamping member 22 having a fixing part 21 and a clamping part having a clamping part 31. It has the member 32. Each of these members 22 and 32 is in the shape of a mounting plate in its entire shape, and they are overlapped with each other with the clamping member 32 upward, and both of them are in the Y-axis direction in the longitudinal direction parallel to the Y-axis direction. It is supported by the associated operating means 60 so that both sides can slide along the direction (front and rear). In the following description of each part of the gripping means 20, when a word showing a direction is used, unless the special rejection, the gripping means 20 shows the direction in the state supported by the associated operation means 60. .

The fixing member 22 has rectangular through-holes 23 and 24 formed in the front and rear ends, respectively, in front and rear ends thereof, and is further positioned in front of the front through-holes 23 and further positioned on the Y-axis. The part including the surface facing the + direction is the fixing portion 21. The front through hole 23 is a guide hole for guiding the front and rear movement of the clamping portion 31 of the clamping member 32. It also functions.

The through hole 24 at the rear of the fixing member 22 forms an operating region in which the tension spring 62 of the associated operating means 60, which will be described later, is disposed and expands and contracts. One end of the tension spring 62 is connected to the front end of the rear through hole 24.

In addition, a bracket portion 25 which is oriented in the X-axis direction is disposed at a position near the rear of the Y-axis middle part of the fixing member 22 and a round rod-shaped coupling pin 26 extending downwards at the distal end thereof. ) Is being fixed. The fixing member 22 receives the moving force in the front-rear direction by the related operation means 60 through the coupling pin 26.

The clamping member 32 is divided into two parts, the front part 33 and the back part 34, and they are connected by the connecting body 35, and form the integral nearly long plate shape. A gripping portion 31 is disposed at the front end portion of the front side 33, and the gripping portion 31 has a flat portion 30 which can be folded and contacted with the fixing portion 21 and the fixing portion 21 is in contact therewith. It has a bent part 36 which passes through the lower side of () and protrudes ahead of the front end surface of the fixing member 22. As shown in FIG.

Accordingly, the upper thread inserted into the front through hole 23 of the fixing member 22 by the closest approach motion between the fixing member 22 and the clamping member 32 is fixed to the clamping portion 21 and the clamping portion 31. It can be pinched by the flat part 30 of the. Moreover, the clamped upper thread can be bent toward the front by the bent part 36 protruded forward from the lower end of the flat part 30, and the upper thread can be made to bend from the front side downward. As a result, the upper thread end is stretched in a state located in front of the bent portion 36, so that the upper thread end is shifted forward than the center drum 122 of the drum mechanism 120 positioned below it, and the contact with the drum north 122 is made. Can be prevented or wound up.

The rear side portion 34 has a through hole 37 formed along the front and rear direction, and the through hole 37 when the holding member 32 and the fixing member 22 are supported by the associated operating means 60 in a state where they overlap with each other. Is overlapped with the rear through-hole 24 of the fixing member 22 described above, and the tension spring 62 of the associated operation means 60 is disposed inside these to form an operation region for stretching. The other end of the tension spring 62 is connected to the rear end of the through hole 37. Therefore, the clamping member 32 is connected to the tension spring 62 of the fixing member 22, and the fixing part 21 of the fixing member 22 and the clamping part 31 of the clamping member 32 are always mutually connected. The elastic force is applied in the approaching and touching direction.

In addition, a bracket portion 38 extending in the X-axis + direction is disposed at the middle portion of the clamping member 32 in the Y-axis direction, and a round bar-shaped coupling pin 39 directed downward is fixed to the tip portion thereof. have. The holding member 32 receives a moving force in the front-rear direction by the associated operation means 60 through the coupling pin 39.

(Means of movement of upper thread lock)

The moving means 40 will be described with reference to Figs. 2, 3, 6, 10 and 12.

The moving means 40 is positioned and sewn to the first moving position below the shanghai east path N of the sewing needle before sewing starts with respect to the fixing portion 21 and the sandwiching portion 31 of the clamping means 20. After starting, when the sewing needle of the first seam is removed from the fabric, the sewing needle is positioned with respect to the vertical movement path (N) of the sewing needle to the second moving position, which is rearward from the first moving position. (For example, 2 to 3 seams) A three-step positioning is performed for positioning the sewing needle to the third moving position which is rearward of the second moving position with respect to the shanghai path N of the sewing needle.

Therefore, the moving means 40 includes the Y-axis moving mechanism 41 for reciprocating the clamping means 20 supported by the associated operation means 60 along the Y-axis direction, and the clamping means 20 are first to first. Moving position detecting means 40 for detecting whether or not it is located at each of the three moving positions, and moving positioning control means for controlling the operation of the Y-axis moving mechanism based on the detection of the moving position detecting means 46.

2 and 3, the Y-axis moving mechanism 41 has a thread catching motor 42 for outputting rotational driving force, and a main linking body 43 having its swing center position connected to the output shaft of the thread catching motor 42. The driving link body 44 transmits the driving force from the main link body 43 to the driven link body 44 and the driven link body 44 which imparts the movement force in the Y-axis direction to the relative position control link 63 of the associated operation means 60. The transmission link body 45 is provided.

The actual catching motor 42 is a stepping motor and is driven at an arbitrary rotational angle with respect to the direction by the operation control of the operation control means 80.

The main link body 43 is fixedly connected to the output shaft of the motor 42 whose one end is threaded, and the other end thereof is rotatably connected to one end of the transmission link body 45.

One end of the driven link member 44 is axially supported by a guide plate 61 to be described later of the associated operation means 60, and the other end thereof is connected to the other end of the transmission link member 45 so as to be rotatable. In addition, a coupling protrusion 52 for imparting a moving force along the Y-axis direction to the relative position adjusting link 63 of the associated operation means 60 is disposed in the substantially <-shaped driven link member 44.

The transmission link member 54 swings the driven link member 44 along with the oscillation of the main link member 43 caused by the driving of the motor 42 that is disposed and substantially runs along the Y axis direction.

When the actual motor 42 is driven by these configurations, the driven link member 44 swings together with the swinging of the main link member 43, and the relative position of the associated operation means 60 is adjusted through the engaging protrusion 52. The link 63 moves along the Y axis direction.

The moving position detecting means 46 will be described with reference to FIGS. 6, 10, and 12. 2 and 3, the moving position detecting means 46 is not shown.

The moving position detecting means 46 has a light emitting element and a light receiving element, and the first and second state sensors 47 and 48 for detecting the presence or absence of a shield therebetween, and the aforementioned Y axis moving mechanism 41. And a shielding plate 51 which is disposed on the transmission link member 45 and has first and second shielding regions 49 and 50.

The first and second state sensors 47 and 48 are arranged side by side along the moving line of the shielding plate 51 and the first state sensor 47 is disposed at the rear side. Thereby, each state sensor 47 and 48 will be in the state arrange | positioned substantially along the Y-axis direction. The light receiving elements of the respective state sensors 47 and 48 turn the state with the shield ON and the state without the shield with the OFF state, and output a signal to the operation control means 80 in which the state is identifiable.

Meanwhile, the shielding plate 51 is fixed to the transmission link member 45 so as to pass between the light emitting element and the light receiving element with respect to both of the first and second state sensors 47 and 48.

In addition, the first shielding area 49 is located between the first state sensor 47 and the second state sensor 48 when the clamping means 20 is in the first moving position as shown in FIG. In the Y-axis direction position as shown in Fig. 10, the first state sensor 47 is shielded, and when in the third moving position, as shown in Fig. 12, the first state sensor 47 is shielded. And the Y-axis direction length are set.

Also, as shown in FIGS. 6 and 10, the second shielding area 50 is located in front of the first state sensor 47 in any case when the clamping means 20 is in the first moving position or the second moving position. When in the third moving position, the Y-axis direction position is set such that the first state sensor 47 is shielded as shown in FIG.

Therefore, in the operation control means 80, it can be confirmed that both the first and second state sensors 47 and 48 are in the OFF state, and the gripping means 20 is in the first moving position. It can be seen that the first state sensor is in the ON state and that the second state sensor 48 is in the OFF state, and that the gripping means 20 is in the third movement position. It is possible to confirm that both of the state sensors 47 and 48 are in the ON state.

The moving position determination control means will be described. Such movement positioning control means is actually realized by the control of the operation control means 80. In this way, the movement positioning control means may be realized by borrowing a part of the control means function for controlling the operation of the entire sewing machine, or may be realized by independent control means.

The motion control means 80 as the movement position determination control means is provided in advance from the rotation angle of the thread catching motor 42 and the second movement position for moving the clamping means 20 from the first movement position to the second movement position. The rotation angle amount for moving to the third movement position is stored. When positioning the clamping means 20 to the second and third movement positions, the operation control of the actual motor 42 is performed with reference to the storage angle position.

In addition, for the first moving position, the operation control means 80 controls the initial position control unit by using the movement position detecting means 46 when the main power is supplied to the sewing machine 100, and drives the actual motor 42. Both positions of the first and second state sensors 47 and 48 are searched for in the OFF state and wait at that position.

In addition, if the output shaft angle is 245 [deg.] By the encoder 109 of the sewing machine motor 105 in the first seam after sewing starts, the sewing needle 104 recognizes that the sewing needle 104 is pulled upward from the fabric and is interposed with the clamping means 20 Control as the upper thread fixing control unit for positioning () to the second moving position. In addition, in the sewing machine 100, the needle needle 104 passes through the bottom dead center when the needle needle 104 rotates to 245 ° when the top dead center position of the sewing needle 104 is set to 0 ° with respect to the output shaft of the sewing machine motor 105. It is set to fall to the top of 108.

When the needle drop is detected a predetermined number of times after the start of correction by the output of the encoder 109, the control as the upper thread release control unit for positioning the clamping means 20 to the third moving position is performed.

(Related operating means of upper thread fixing device)

The related operation means 60 will be described with reference to Figs.

The associated operation means 60 includes a guide plate 61 as a guide means for supporting the support member 32 and the fixing member 22 so as to be reciprocated along the Y-axis direction, the clamping portion 31 and the fixing portion 21. The tension spring 62 to the tension applying means for imparting a constant tension between the clamping member 32 and the fixing member 22 in the direction in which the () approaches each other, and the clamping portion (31) in accordance with the posture change by its own swing. ) And the fixing portion 21 can be folded so as to be coupled to the holding member 32 and the fixing member 22, and the holding means 20 by the moving means 40 is moved to the first moving position. The first contact member 64 and the clamping means 20 which are in contact with the relative position control link member 63 and swing in the direction separating the clamping portion 31 from the fixing portion 21, the clamping means 20 in the third moving position. In this case, the second contact member 65 which contacts the relative position control link member 63 and swings in the direction separating the clamping portion 31 from the fixing portion 21 is provided. Have

The guide plate 61 is an upper portion of the sewing machine bed 103 and is fixed to the rear of the needle plate 108. In the following description of each part of the associated operation means 60, when a language indicating the direction is used, the guide plate 61 indicates the direction in the state of being fixed to the sewing machine bed 103 unless otherwise specified. do.

On the upper surface of the guide plate 61, the guide groove 66 along the Y-axis direction is arrange | positioned at the intermediate position in the X-axis direction. In the guide groove 66, the fixing member 22 and the sandwiching member 32 of the sandwiching means 20 are stored in an overlapped state in the longitudinal direction, and the pressing plate 67 is disposed thereon. The lid is covered so that the member 32 does not fall from the guide groove 66. Accordingly, the fixing member 22 and the holding member 32 are guided to the guide groove 66 so that they can slide along the Y-axis direction, respectively. do. However, as described above, since the fixing member 22 and the clamping member 32 are connected through the tension spring 62, the members 22 and 32 are fixed to the clamping portion 21 and the clamping portion unless an external force is applied. It keeps the state which contacted (31). 7, 9, 11 and 13, the width of the fixing member 22 and the interposing member 32 in the X-axis direction are shown to be different, but this clearly shows the relative positional relationship of each member 22 and 32. In other words, the fixing member 22 and the clamping member 32 are set to be substantially equal to the width of the X-axis direction of the guide groove 66 in the range in which the sliding member can slide.

Further, through holes 68 and 69 are disposed on both sides with guide grooves 66 of the guide plate 61 interposed therebetween. One through hole 68 is fitted with a coupling pin 26 disposed on the fixing member 21 from above, and the other through hole 69 is fitted with a coupling pin 39 of the clamping member 32. In addition, each of the through holes 68 and 69 has a movement from the first moving position to the third moving position of the clamping means 20 and the relative movement of the fixing member 22 and the clamping member 32 accompanying it. The Y-axis direction length is set so that neither the front end part nor the rear end part of each hole may contact each coupling pin 26 and 39. As shown in FIG. In addition, each of the coupling pins 26 and 39 inserted into the through holes 68 and 69 has a distal end portion protruding from the lower surface side of the guide plate 61 to be coupled to the relative position control link member 63 separately. do.

The relative position adjustment link member 63 is arranged in a line along the longitudinal direction, and the rotational coupling portion 71 with the holding member 22 and the rotational coupling portion 71 with the clamping member 32 and the moving means positioned therebetween. The rotational coupling part 72 with the 40 is arrange | positioned.

That is, the rotation coupling part 70 with the fixing member 22 is inserted into the coupling pin 26 through the long hole-shaped through-hole along the longitudinal direction of the relative position control linkage (63). Rotating coupling portion 71 with the clamping member 32 is inserted through the coupling pin 39 into a circular through hole. The rotation engaging portion 72 with the moving means 40 is inserted into the engaging projection 52 through the long hole-shaped through-hole along the longitudinal direction of the relative position control linkage (63).

FIG. 14 is an explanatory view seen from below showing the relationship between the swinging motion of the relative position adjusting link member 63 and the corresponding positional change of the fixing member 22 and the clamping member 32. FIG.

Referring to Fig. 14, the fixing member 22 and the clamping member 32 are in contact with the fixing portion 21 and the clamping portion 31 by the tension spring 62, as long as they are not subjected to an external force as described above. maintain. This state becomes a fixed state of the upper thread. Each of the coupling pins 26 and 39 aims to be positioned at approximately the same position with respect to the Y-axis direction when the fixing portion 21 and the clamping portion 31 are in contact with each other. Accordingly, the relative positioning link body 63 connected through each of the coupling pins 26 and 39 and the rotational coupling parts 70 and 71 also has an almost X-axis in the normal state by tensioning the tension spring 62. The state along the direction is maintained (state shown by the solid line in FIG. 14).

In this state, for example, when a counterclockwise rotational force is applied to the relative position adjusting link member 63 by the Y-axis movement force from the engaging protrusion 52 of the moving means 40, the relative position adjusting link. The sieve 63 swings and changes its posture. At this time, by causing displacement in the Y-axis direction in each of the rotational coupling parts 70 and 71, the fixing part 21 and the clamping part 31 are separated from each other between the fixing member 22 and the clamping member 32. External force in the direction is given. Therefore, the fixing portion 21 and the clamping portion 31 are separated from each other in accordance with the tension of the tension spring 62, and converted from the fixed state of the upper thread to the released state.

The first contact member 64 will be described with reference to FIGS. 7, 9, and 14. The first contact member 64 makes the fixing portion 21 and the clamping portion 31 separated from each other when the clamping means 20 is in the first moving position, and moves from the first moving position to the second moving position. The fixed part 21 and the clamping part 31 move in the direction which approaches each other, and operate the rocking | fluctuation of the relative position adjustment link body 63 so that it may reach until it reaches a 2nd moving position.

In order to realize the above-described operation, the first contact member 64 is connected to the rotation engaging portion 72 of the moving means 40 and the clamping member 32 with respect to the relative position control link member 63 positioned at the first moving position. It is arrange | positioned so that it may contact from the front side between the rotational coupling parts 71. FIG. In this arrangement, the relative position adjustment link is provided when the relative position adjustment link member 63 is provided with a moving force to the front by the movement means 40 to position the clamping means 20 at the first movement position. The sieve 63 swings with the contact point of the first contact member 64 in correspondence with the tension of the tension spring 62. At that time, the pivot coupling portion 71 of the clamping member 32 moves backward and the pivot coupling portion 70 of the fixing member 22 moves forward than at the time of contact. Therefore, the fixing part 21 is moved forward through the holding member 22, and the holding part 31 moves backward through the holding member 32, so that they are separated from each other (see FIGS. 6 and 14 two-dot chain lines). ). In this state, insertion of the upper thread end portion is performed between the fixing portion 21 and the clamping member 31.

When the clamping means 20 moves from the first moving position to the second moving position, the contact state to the relative position adjusting link member 63 by the first contact member 64 is gradually released, so that the relative position adjusting link member 63 is released. ) Rotates clockwise by the tension of the tension spring 62. Therefore, the relative position control link member 63 rotates clockwise until the contact state with the first contact member 64 is completely released, and the gripping portion 31 moves forward through the gripping member 32. At the same time, the fixing part 21 moves backward through the fixing member 22. For this reason, the holding | gripping of the upper thread by the fixing | fixed part 21 and the clamping part 31 is located behind the fixing part 21 in a 1st moving position, and is ahead of the clamping part 31 in a 1st moving position. Will be done at.

The second contact member 65 will be described with reference to Figs. 11 and 13. The second contact member 65 moves the clamping part 21 and the clamping part 31 which are in the clamped state again in a direction to separate the clamping means 20 when the clamping means 20 moves from the second moving position to the third moving position. The swing of the relative position adjustment link 63 is operated.

In order to realize the above operation, the second contact member 65 has one side in the X-axis direction with respect to the region where the relative position adjusting link member 63 passes when the clamping means 20 moves from the second moving position to the third moving position. Is disposed so as to slide in contact with the relative position control linkage (63).

For this reason, the sliding contact portion 63a disposed at the end portion of one side of the X-axis direction of the relative position adjustment link member 63 approaching to the third movement position in the state substantially along the X-axis direction (see Fig. 11) is provided. The two contact members 65 slide and touch. Since the sliding portion 63a of the relative position adjustment link member 63 is gradually extended toward the -axis in the X-axis direction, the relative position adjustment link member 63 is moved back to the rear after the sliding position starts to reach. The relative position adjusting link member 63 swings in the counterclockwise direction as shown in Fig. 13, and the gripping means 20 reaches the third moving position in this state. Due to this swing, the pivotal coupling portion 71 of the clamping member 32 is moved to the rear larger than the pivotal coupling portion 70 of the fixing member 22. As a result, the fixing part 21 and the clamping part 31 will be in the state separated from each other (refer FIG. 13). In this process, release of the upper thread end fixed between the fixed part 21 and the clamping part 31 is performed.

(Position of fixing part and clamping part in each moving position)

When the clamping means 20 is positioned in the first moving position, the fixing part 21 and the clamping part 31 move in the direction away from each other as described above. When the first moving position is reached, as shown in FIG. 6, the fixing part 21 is positioned in front of the shanghai east path N of the sewing needle.

In addition, in the clamping portion 31, the distal end portion of the bent portion 36 is located at least behind the straight line M. FIG. This straight line M is sewn from the rear edge portion at the lower end of the needle hole 108a (the position of the end of the Y-axis direction-side of the diameter along the Y-axis direction of the circular needle hole 108a viewed from below). It is a straight line determined to connect the upper end part of one race surface 128 which becomes the back of the drum 122 which is arrange | positioned near the back of the shanghai east route N of a needle. By setting the distal end portion of the clamping portion 31 in this way, the upper seal loop by the first seam in sewing is captured by the pointed end 121 of the central drum 122, and the thread division part of the upper thread guide plate 124 ( In the case of spreading (expanded) by 124b, the upper end of the clamping portion 31 contacts the upper thread so that the thread division 124b can unfold the loop so that the upper thread contacts the race face 128 effectively. It becomes possible to suppress it.

Further, the position of the fixing portion 21 or the line unit value of the clamping portion 31 is the first contact member with respect to the Y-axis length or the relative position adjusting link member 63 of the fixing member 21 and the clamping member 32. It is determined by the contact position of (64). For example, if the contact position of the first contact member 64 is near the rotational coupling portion 72 of the moving means 40, the position of the fixing member 21 is further forward, and the line unit of the clamping portion 31 Even more backwards. In addition, if the contact position is near the rotational coupling portion 71 of the clamping member 32, the position of the fixing portion 21 is further rearward, and the line unit value of the clamping portion 31 is further forward.

The position where the clamping part 20 and the flat part 30 of the clamping part 31 touch, and become a clamping state in the process of positioning the clamping means 20 from a 1st moving position to a 2nd moving position (next " Location &quot;) is closer to the shanghai east path N of the sewing needle as shown in FIG. This is because the length of the upper thread end extending from the clamping means 20 can be shortened by pinching the upper thread end at a position close to the sewing needle 104.

8 is a view showing an example of a pinching position at which the pinching of the upper thread end is performed. Although the pinching position is located slightly to the side of the shanghai east path N of the sewing needle, in the present invention, the fixing portion 21 and the pinching pin are made. In the configuration in which the branches 31 move together, when the sewing needle 104 is located at the shanghai eastward position below the needle plate 108, the fixing portion 21 and the pinching portion 31 are moved up and down the sewing needle 104. Since it can be located in a position which does not interfere with movement, it is also possible to place the pinching position again on the shanghai east path N of the sewing needle, for example, on the shanghai east path N of the needle.

The distance from the pinching position to the shanghai east path of the sewing needle is also determined by the contact position of the first contact member 64 with respect to the relative position adjusting link member 63. For example, if the contact position of the first contact member 64 is near the pivotal coupling portion 72 of the moving means 40, the clamping position is brought closer by the shanghai copper path N, and the contacting position is the clamping member 32. In the vicinity of the rotation coupling portion 71 of the pinching position is moved away from the Shanghai East Route (N).

When the clamping means 20 is positioned in the second moving position, since the fixing portion 21 and the clamping portion 31 are in contact with each other in advance, the mutual arrangement is in the same state.

In addition, the second moving position may be a position where the fixing portion 21 and the clamping portion 31 deviate from the shanghai copper path N of the sewing needle and do not interfere with the sewing needle 104.

When the clamping means 20 is positioned in the third moving position, the fixing part 21 and the clamping part 31 may be spaced apart as far as possible to release the upper thread.

In addition, in the third moving position, the fixing portion 21 and the clamping portion 31 may be located at a position that does not interfere with the sewing needle 104 from the shank east path N of the sewing needle. It is set behind the second moving position so as not to interfere.

(Operation control means)

The operation control means 80 will be described with reference to FIG. 15 is a block diagram showing a control system of the sewing machine 100. Although not shown in detail, such control means 80 includes a CPU which performs various arithmetic processing, a ROM in which various programs for various processing such as control and judgment are stored and stored, and a RAM used as a work-memory in various processing. It consists of outline. The control means 80 includes a sewing machine motor 105, an encoder 109, a thread catching motor 42, a first position sensor 47 of the movement position detecting means 46, and the like through a system bus and a driving circuit. The second state sensor 48 and the S / S (start stop) switch 81 of the sewing machine 100 are connected.

The control means 80 may recognize the rotation angle of the sewing machine motor 105 based on the pulse signal input from the encoder 109 disposed on the output shaft of the sewing machine motor 105.

In addition, the control means 80 can check each movement position of the clamping means 20 based on the detection signals input from the first state sensor 47 and the second state sensor 48 of the movement position detecting means 46. have.

In addition, the control means 80 moves according to the detection of the rotation angle of the sewing machine motor 105 or the operation position of the moving position clamping means 46 when the sewing start signal is input from the start switch 81. The actual job control of the motor 42 is controlled.

(Explanation of operation of sewing machine)

6 to 16 illustrate the operation of the sewing machine 100 having the above configuration. 16 is a flowchart showing operation control of the sewing machine 100.

First, the control means 80 performs the first movement position detection (initial position detection) by the movement position detection means 46 based on the sewing start signal from the S / S switch 81 (step S1). This detection is determined by whether both the first and second state sensors 47 and 48 are in the OFF state.

As described above, the operation control 80 is positioned by the moving position detecting means 46 when the main power is input to the first moving position. Therefore, the pinching means 20 is located on the shanghai east path N of the sewing needle, and the fixing part 21 is located in front of the shanghai east path N of the sewing needle, and on the shanghai east path N of the sewing needle. Position, the fixing portion 21 is located in front of the shanghai east path (N) of the sewing needle and the pinching portion 31 is located behind the straight line (M) (FIGS. 6 and 7 state).

In addition, if any one of the first or second state sensors 47 and 48 is detected to be ON due to some factor despite being previously positioned to the first moving position, error processing (display, warning, etc.) is performed ( Step Sa1), the operation | movement of each part of the sewing machine 100 is stopped (step Sa2), and a process is complete | finished.

On the other hand, when both of the first and second state sensors 47 and 48 are detected in step S1, the drive of the sewing machine motor 105 is started (step S2). Accordingly, the sewing needle 104 is inserted into the needle hole 108a of the needle plate 108 and the upper thread passes between the fixing portion 21 and the clamping portion 31. In addition, the upper seal loop next to the sewing needle 104 is captured at the pointed end of the drum mechanism 120. And the upper seal is expanded by the rotation of the center drum 122 and the upper thread guide plate 124, but at the time, the front end of the clamping portion 31 is located at the rear so that the enlargement of the upper seal by the upper thread guide plate 124 is performed. Do not block. Therefore, contact of the upper thread to the rear race face 128 is prevented.

In addition, it is determined from the detection angle of the encoder signal whether the sewing needle 104 of the first seam from the encoder 109 of the sewing machine motor 105 has fallen out of the fabric and the balance 107 has reached a top dead center (step S3). The process of step S3 is repeated until it reaches. When the output of the encoder 109 indicates that the balance 107 reaches the top dead center, the operation control means 80 moves the clamping means 20 to the second moving position on the actual motor 42 of the moving means 40. Operation control to start the drive is performed so as to make it operate (step S4). That is, the motor 42 holding the thread is driven by referring to the memory of the rotation angle amount corresponding to the movement amount from the first movement position to the second movement position which is set in advance.

Accordingly, the gripping means 20 starts moving from the first moving position toward the second moving position. Accordingly, since the relative position control linkage 63 of the associated operation means 60 starts swinging along the X-axis direction by the tension of the tension spring 62, the fixing portion 21 moves backwards, and the clamping portion 31 moves forward and approaches each other, and the flat part 30 of the fixed part 21 and the clamping part 31 contacts (FIG. 8, 9). As a result, the upper thread end inserted between them is sandwiched. The position of the clamping portion 31 in the first moving position is because the clamping position touches each other by the fixing portion 21 and the clamping portion 31, which are located on both front and rear sides of the shanghai-dong path N of the sewing needle. Rather, the pinching position becomes a position close by the shanghai east path N of the sewing needle.

After the balance 107 reaches the top dead center, the upper thread end is clamped by the fixing portion 21 and the clamping portion 31 because the lifting of the balance with respect to the upper thread is completed at the top dead center of the balance 107. The upper thread below the hole 108a is in the shortest state, and when the upper thread is clamped by the fixing part 21 and the clamping part 31, the length of the upper thread from the pinched part to the end can be shortened. Because.

Since the clamping position is in front of the second moving position, the clamping means 20 continues to move further backward by the moving means 40. When the driving of the actual grabbing motor 42 by the amount of rotation angle is performed and stopped, the operation control means 80 confirms the output of each state sensor 47, 48 of the movement position detecting means 46 ( Step S5). In the second moving position, it is normal that the first state sensor 47 is in the ON state and the second state sensor 48 is in the OFF state, but a state other than this is detected for any one of the sensors 47 and 48. If so, an error process (display, warning, etc.) is performed (step Sa1), the operation of each part of the sewing machine 100 is stopped (step Sa2), and the process ends.

In addition, when each sensor showed the appropriate state in step S5, sewing continues as the upper thread was fixed to the clamping member 20. FIG. That is, the sewing machine 100 performs sewing after the second seam (step S6). In addition, the gripping means 20 having reached the second moving position is only rearward, and the relative positional relationship between the fixing part 21 and the gripping part 31 does not change after the upper thread is clamped. Therefore, even after reaching the second moving position, the upper thread end is held (Figs. 10 and 11). The movement to the second moving position is also completed while the needle tip of the sewing needle 104 is above the needle plate 108.

Then, the control means 80 judges whether a predetermined number of needle drops (for example, two needle drops) have been performed (step S7). The number of needle drops can be recognized, for example, by counting the number of times of signal output showing 180 degrees by the encoder 109.

If it is determined that the predetermined number of needle drops has not been performed (step S7: NO), the control means 80 repeats the process of step S7 until the predetermined number of needle drops has been performed.

On the other hand, if it is determined that the predetermined number of needle drops has been performed (step S7: YES), the control means 80 proceeds to step S8.

The operation control means 80 performs operation control for starting the drive to move the clamping means 20 to the third moving position to the actual motor 42 of the moving means 40 (step S8). That is, the motor 42 holding the thread is driven by referring to the memory of the rotation angle amount corresponding to the movement amount from the second movement position to the third movement position which is set in advance.

Accordingly, the gripping means 20 starts moving from the second moving position toward the third moving position. And when the clamping means 20 approaches the 3rd moving position, the sliding part 63a of the relative position control link body 63 of the related operation means 60 slides and touches the 2nd contact member 65. As shown in FIG. In addition, if the movement of the clamping means 20 continues, the relative positioning link member 63 swings against the tension of the tension spring 62, and the clamping portion 31 moves to the rear larger than the fixing portion 21. . Therefore, the clamping state of the upper thread end is released and the upper thread end is released from the clamping means 20 while the clamping means 20 reaches the third moving position (Figs. 12 and 13).

After reaching the third movement position, the operation control means 80 confirms the output of each state sensor 47 and 48 of the movement position detection means 46 (step S9). In the third moving position, it is normal that the first state sensor 47 is in the ON state and the second state sensor 48 is in the ON state, but any other state is detected for either of the sensors 47 and 48. In this case, error processing (display, warning, etc.) is performed (step Sb1) to end the processing.

Next, the control means 80 judges whether sewing is complete (step S10). If the control means 80 determines that sewing has not been completed (step S10; NO), the sewing step S10 repeats the processing when sewing is finished.

On the other hand, when the control means 80 determines that sewing is complete (step S10; YES), it progresses to step S11.

When the sewing is finished, the operation control means 80 outputs a driving signal to the thread cutting motor (not shown) of the thread cutting mechanism, and the thread associated with the upper thread and the sewing by the thread cutting mechanism by the driving force of the thread cutting motor 82. An actual cutting is performed (step S11).

Then, the operation control means 80 outputs a drive signal to the actual motor 42 of the moving means 40, and the clamping means 20 moves from the third moving position to the first moving position by the driving force of the motor 42. It moves to (step S12).

Then, one cycle related to sewing of the sewing machine 100 having the upper thread fixing device 10 is completed by passing through these step S1 processing to step S12 processing (including step Sa1 processing, step Sa2 processing, and step Sb1 processing). .

The operation of the sewing machine 100 is performed as described above.

(Effect of Embodiment)

The effect of the upper thread fixing device 10 will be described based on FIGS. 17 and 18. FIG. 17 is an explanatory diagram showing a clamping means 20 of the upper thread fixing device 10 in a simplified, two-dot chain line, and FIG. 18 is a simplified diagram showing a clamping means 200 of the upper thread fixing device in a comparative example, a double-dashed line. It is an explanatory diagram.

In the comparative example of FIG. 18, since the clamping portion 231 is close to the shanghai east side of the sewing needle, the upper seal is narrowly formed by contact with the clamping portion 231, and the guide hole of the upper thread guide plate 124 is provided. The thread division by the thread division part 124b arrange | positioned at 124a is not fully performed, and it is easy to produce a contact with the north shaft side race surface 128 of the center drum 122. As shown in FIG.

On the other hand, as shown in Fig. 17, when the clamping means 20 of the upper thread fixing device 10 is positioned at the first moving position by the associated operation means 60, the clamping portion 31 has the straight line M (described above). 6) It is disposed behind (north axis), so that it can escape from the shanghai east path of the sewing needle, and the upper thread end and the clamping part 31 can be avoided when the upper thread end is fixed. Therefore, the upper thread end does not come into contact with the raceway side 128 of the central drum 122, and the thread sharing by the thread sharing part 124b is reliably performed, so that the loop is greatly enlarged, and the upper thread end is contaminated or wound around the drum. I can reduce a feeling effectively.

On the other hand, the associated operation means 60, when the clamping means 20 is moved from the first moving position to the second moving position, the fixing part 21 toward the clamping part 31 side, and the clamping part 31 is fixed to the fixing part 21. The position of the sandwiching part 31 at the time of clamping can be moved to the shanghai east path N side of a sewing needle by moving to the side). As a result, fixing of the upper thread end is performed near the shanghai east path N of the sewing needle, and the length of the end side of the upper thread end after the pinching can be shortened.

In particular, even in the case of retracting the pincer part to the position away from the shanghai east path (N) of the sewing needle to avoid contact with the upper thread as in the present embodiment, the pinch part can be moved near when the pinch is held. It is possible to shorten the upper thread end after the pinching while avoiding contact with the center drum 122.

In the invention of claim 1, the gripping means moves from the position at which the sewing needle moves up and down toward the mouth of the sewing machine. The gripping means moves toward the moving part side of the sewing machine because the gripping means moves in the longitudinal direction of the sewing machine bed. With the same configuration, it is possible to provide an upper thread fixing device applicable to the cylinder bed.

In addition, when moving from the first moving position to the second moving position of the clamping means, the fixing part moves to the clamping part side, and the clamping part is moved to the fixing part side, so that the upper thread end is sandwiched therebetween. The upper thread end of the pinching part can be shortened by being close to the shanghai east path side of the sewing needle at the time of upper thread narrowing, even if it is not arranged near the shanghai east path.

Therefore, in the first moving position, it is possible to position the pincer apart from the shanghai path of the sewing needle, so that the pinch is sewn so as not to interfere with the expansion by the upper thread guide plate of the upper seal which is caught by the pointed end of the north drum. Since it is not possible to place it enough on the Shanghai east route, the restriction that the length of the upper thread remaining in the Cheonan side cannot be shortened is removed, so that the length of the upper thread end remaining inside the fabric at the start of sewing can be shortened sufficiently.

The invention of claim 2 is that the gripping portion is disposed on the north axis side of the gripping portion when the gripping means is in the first moving position, and the tip portion thereof is disposed on the north axis side rather than a straight line that binds the north side side edge of the needle hole and the top edge of the north side race surface of the center north. It is possible to effectively avoid the contact between the clamping part and the upper thread when the upper seal loop of the one seam is unfolded by the upper thread guide plate, and effectively reduce the situation that the upper thread is placed on the race face side of the north shaft by the contact with the clamping part. More effectively, the contact between the raceway side of the shaft and the upper thread can be prevented.

Claim 3 of the present invention provides a contact member for providing a folding action to both the fixed portion and the clamping portion by swinging the relative position adjusting link member and swinging the relative position adjusting link member in the first and third moving positions, respectively. As a result, both the fixed portion and the sandwiching portion can be moved in accordance with the movement of the sandwiching means to each moving position to achieve the folding thereof.

Therefore, it is possible to carry out the operation of claim 1 or 2 with only one driving source for movement of each moving position of the gripping means, thereby improving the productivity of the apparatus and simplifying the control system even when disposing the control means. It becomes possible to plan.

Claims (4)

At the start of sewing, the end of the upper thread inserted into the sewing needle is pinched at the bottom of the needle plate and above the passage path of the pointed end of the center drum with respect to the sewing needle, and the end of the pinched upper thread is held at the sewing needle. In the upper thread fixing device of the sewing machine to move to a position away from the shanghai east route of the, and to open the end of the pinched upper thread after the needle drop of a predetermined number of needles, A fixing portion for fixing the end of the upper thread and a holding portion for relatively opening the end of the upper thread between the fixing portion and moving between the fixing portion and the holding position relative to the fixing portion, A first moving position located on the east path, a second moving position spaced apart from the first moving position to the moving part side of the sewing machine with respect to the shanghai moving path of the sewing needle, and from the second moving position And a gripping means for moving to the third moving position spaced apart from the shanghai east path of the sewing needle to the entrance side of the sewing machine again; Moving means for moving the clamping means from the first moving position to the second moving position at the start of sewing, stopping for a predetermined number of needle drops, and then moving from the second moving position to the third moving position; , When the gripping means is located at the first moving position, the gripping portion is disposed at a position on the inlet side of the sewing machine from the shanghai east route of the sewing needle, and the fixing portion is located between the shanghai east route of the sewing needle. It is disposed at a position opposite to the gripping portion, and when the gripping means moves from the first moving position to the second moving position, both the fixing portion and the gripping portion move in a direction approaching each other to the upper thread end portion. And the gripping portion is moved at the same time as the gripping means is moved to the second moving position and the gripping means moves from the second moving position to the third moving position or at the third moving position. The gripping portion and the fixing portion are machined in the moving means to isolate the fixing portion and open the sandwiched upper thread end. Upper thread fixing device of a sewing machine, characterized in that it comprises an associated operation means for connecting to. The method of claim 1, The associated operation means, The tip end portion of the gripping portion when the gripping means is located at the first moving position is more than a straight line which binds the north axis side edge of the needle hole arranged in the needle plate and the upper edge of the north axis side race surface of the middle north. Located on the north axis side, The upper thread fixing device of the sewing machine, characterized in that the pinching portion and the pinching portion sandwiched the end of the upper thread in the vicinity of the shandong east path of the sewing needle. The gripping means has a fixing member having the fixing portion, and a holding member having the holding portion, The associated operation means, Guide means for supporting the holding member and the fixing member to be reciprocated in a direction along the north axis, respectively; Tension biasing means for providing constant tension between the clamping member and the clamping member in a direction in which the clamping portion and the clamping portion approach each other; It is possible to fold the gripping portion and the fixing portion according to a change in posture due to its own swing, so as to be coupled to each of the gripping member and the fixing member, and to move to the respective moving position of the gripping means by the moving means. A relative position adjusting link body into which a force is input, A first contact member which swings in a direction separating the gripping portion from the fixing portion by contacting the relative position adjusting link member when the gripping means is in the first moving position; When the gripping means is in the third moving position and has a second contact member to be in contact with the relative position control link member to swing in the direction separating the gripping portion and the fixed portion, The relative position control link member is disposed in the rotational coupling portion of the rotational coupling portion with the holding member and the rotational coupling portion with the fixing member and the moving means located between them so as to follow the longitudinal direction, The first contact member is the upper thread fixing device of the sewing machine, characterized in that the contact between the rotational coupling portion and the rotational coupling portion and the moving means with the holding member. The method of claim 2, The associated operation means, Guide means for supporting the holding member and the fixing member to be reciprocated in a direction along the north axis, respectively; Tension biasing means for providing constant tension between the clamping member and the clamping member in a direction in which the clamping portion and the clamping portion approach each other; It is possible to fold the gripping portion and the fixing portion according to a change in posture due to its own swing, so as to be coupled to each of the gripping member and the fixing member, and to move to the respective moving position of the gripping means by the moving means. A relative position adjusting link body into which a force is input, A first contact member which swings in a direction separating the gripping portion from the fixing portion by contacting the relative position adjusting link member when the gripping means is in the first moving position; When the gripping means is in the third moving position and has a second contact member to be in contact with the relative position control link member to swing in the direction separating the gripping portion and the fixed portion, The relative position control link member is disposed in the rotational engaging portion with the holding member and the rotational engaging portion with the fixing member and the rotational engaging portion located between them so as to follow the longitudinal direction, The first contact member is the upper thread fixing device of the sewing machine, characterized in that the contact between the rotational coupling portion and the rotational coupling portion and the moving means with the holding member.