JP6441221B2 - sewing machine - Google Patents

Description

  The present invention relates to a sewing machine including a thread trimming device that cuts an upper thread and a lower thread.

  In a sewing machine that forms a seam by knotting the upper thread and lower thread through the cooperation of the needle up-and-down movement mechanism and the shuttle mechanism, the lower thread and upper thread cloth side portions and the upper thread A thread trimming device that cuts a predetermined sewing thread after performing threading to the sewing needle side portion is provided. As such a thread trimming device, a rotating type in which the knife rotates around the hook and a horizontal type in which the knife moves along a horizontal plane are often used.

  The rotational thread trimming device includes a thread trimming fixed knife and a thread trimming moving knife that are rotatably supported around a vertical hook, and are retracted from a needle drop position during sewing. The fixed knife for scissors advances to the front of the needle drop position when cutting, and the moving knife for thread trimming moves in the direction opposite to the forward direction of the fixed knife for thread trimming and performs threading at the needle dropping position while moving the thread trimming knife. , And the cloth side portions of the lower thread and the upper thread are cut (see, for example, Patent Document 1).

  In addition, the horizontal thread trimming device includes a thread trimming knife that reciprocally rotates back and forth along a horizontal plane so as to pass the needle trimming position, and a thread trimming fixed knife provided in the vicinity of the needle trimming position. The thread trimming knife performs threading during forward rotation, and cuts the lower thread and upper thread on the fabric side in cooperation with the thread trimming knife when rotating backward (for example, , See Patent Document 2).

Japanese Patent Laid-Open No. 07-155589 JP 2007-029437 A

  However, since all of the thread trimming devices of the sewing machine perform thread trimming on the lower side of the needle plate, the thread trimming knife is arranged close to the needle plate so that the cutting position is close to the needle drop position. Even if designed, there is a problem that the remaining end (remaining yarn) more than the thickness of the needle plate remains on the fabric after the yarn is cut. For this reason, when there is a request to make the remaining end as short as possible, it has been necessary to manually cut it.

  Moreover, there are the following problems when the cloth feed is performed using the feed dogs that appear and disappear from the needle plate. That is, in the above thread trimming device, cutting is performed when the sewing needle is positioned near the top dead center so that the sewing needle and the thread trimming knife do not interfere with each other. On the other hand, the feed dog feeds when the sewing needle is raised above the needle plate. Therefore, at the cutting timing, as shown in FIG. It is pushed up from. Therefore, there is a problem that the remaining end of the sewing thread becomes longer because the distance from the fabric to the thread cutting knife is increased by the amount that the feed dog is pushed up from the needle plate.

  Furthermore, when performing cloth feed using the feed dog, if the thread trimming is performed near the top dead center of the sewing needle after the needle drop of the final needle, the feed dog has already started to feed the cloth, so only that feed Since the distance from the fabric to the knife for thread trimming was increased, the remaining end of the sewing thread was long. Furthermore, since the upper thread pulled to the lower side of the cloth by the final needle is cut, the knot between the upper thread and the lower thread is not formed at the needle drop position of the final needle, and the remaining end of the upper thread is the final needle. The remaining end is generated from the needle drop position, and the remaining end of the lower thread is generated from the needle drop position immediately before the final needle. For this reason, as shown to FIG. 13B, the remaining end arises from two distant places, and the fall of sewing quality has arisen.

  An object of the present invention is to make the remaining ends of the upper thread and the lower thread shorter.

  The present invention includes a needle plate through which a needle hole into which a sewing needle is inserted is formed, a moving mechanism that moves a sewing object along the upper surface of the needle plate, and a needle up / down operation that moves the sewing needle up and down. A moving mechanism, a hook mechanism that catches the upper thread from the sewing needle below the needle plate and entangles the lower thread, and is provided between the needle plate and the hook mechanism, and cuts the lower thread and the upper thread. A thread trimming device, a wiper mechanism for pulling out a sewing needle side portion of the upper thread cut by the thread trimming device to the upper side of the sewing product, and operation control of the moving mechanism, the thread trimming device, and the wiper mechanism. A sewing machine including a control device for performing a remaining end cutting mechanism disposed below the upper surface of the needle plate and above the thread trimming device, and cutting the lower thread and the upper thread by the thread trimming device. Later, the remaining ends of the lower thread and the upper thread connected to the sewing product are Characterized by excised by dividing mechanism.

  According to the present invention, the remaining ends of the lower thread and the upper thread on the side of the workpiece to be sewn are cut by the thread trimming device by the remaining end cutting mechanism disposed below the upper surface of the needle plate and above the thread trimming device. Since the cutting is performed, it is possible to reduce the increase in the remaining ends of the lower thread and the upper thread that are caused by the thickness of the needle plate.

In the above invention, the needle plate has an upper and lower two-layer structure, and the remaining end excision mechanism is built in between upper and lower layers of the needle plate, and the lower thread continues to the sewing product after being cut by the thread trimming device. and have a dissecting knife to ablate residual end of the upper yarn, needle hole to be concentric with both the lower needle plate and the upper layer of the needle plate is formed, the remaining end ablation mechanism, the upper layer of the needle Between the plate and the lower needle plate, the excision knife may include a fixed knife on the upper side and a moving knife on the lower side .

  Since the present invention incorporates a cutting knife for the remaining end cutting mechanism that cuts the remaining end of the lower thread and the upper thread on the side of the sewing material cut by the thread trimming device between the upper and lower layers of the needle plate. It is possible to reduce the increase in the remaining ends of the lower thread and the upper thread that are caused by the thickness of the needle plate.

  Further, in the above invention, the control device reduces the feed amount from the needle drop position immediately before the needle drop position of the final needle for performing the thread trimming by the thread trimming device to 0 or less than the feed amount immediately before it. As such, the feed amount of the moving mechanism may be controlled.

  In the above invention, by making the needle drop position of the last needle the same position as or close to the needle drop position of the previous needle, avoiding the extension of the remaining end due to the movement of the sewing product after the needle drop of the last needle, It is possible to avoid a situation that occurs from a position where the remaining end of the upper thread and the remaining end of the lower thread are separated from each other, and it is possible to improve the sewing quality.

  Further, in the above invention, the moving mechanism feeds the sewing material by a feed dog that protrudes and retracts from the retracting hole of the throat plate, and the control device, after cutting the lower thread and the upper thread by the thread trimming device, The remaining end cutting mechanism may be controlled so as to cut the remaining ends of the lower thread and the upper thread after reducing the amount of protrusion of the feed dog from the needle plate by rotating the sewing machine motor. .

  In the above invention, since the remaining ends of the lower thread and the upper thread are cut after reducing the protruding amount of the feed dog, the remaining ends after the cutting can be made shorter.

Further, in the above invention, the control device controls the feed amount of the moving mechanism so that the predetermined number of stitches becomes a predetermined condensation sewing pitch when the input of the thread trimming signal by the signal input means is detected. May be.
In the above invention, it is possible to perform condensation sewing.

In the above invention,
The sewing machine is a button-attached sewing machine that sews a button on a workpiece, and is a sewing machine for the upper thread that is disposed below the needle plate and the remaining end cutting mechanism and above the shuttle mechanism. An upper thread holding device that holds the start end of the upper thread can be switched between a released state of the upper thread sewing end and a clamping state of the upper thread sewing end. And an actuator for switching the clamping means from the released state to the clamped state, and the control device holds the clamping means from the released state after the needle drop of the first needle of the button sewing. The thread is trimmed by the thread trimming device after the last needle drop of the button sewing, and after the thread trimming by the thread trimming device is executed, the clamping means is controlled to be switched to the released state. Good.

Moreover, in the said invention, it is good also as a structure provided with the suction mechanism which performs suction from the needle hole lower part of the said needle plate.
In the above invention, dust can be collected on the lower side of the needle plate by the suction mechanism, and it is possible to reduce the occurrence of malfunction due to dust adhering to the surrounding mechanism or the like.
Further, the remaining ends of the upper thread and the lower thread to be cut by the remaining end cutting mechanism can be extended downward, and the cutting can be performed more reliably.

In the above invention, the suction mechanism may include a suction nozzle capable of moving toward and away from the needle hole of the needle plate and nozzle driving means for applying the contact and separation movement operation.
In the above invention, since the suction nozzle can be moved toward and away from the lower side of the needle plate on which various configurations are arranged, the interference between the other configurations and the suction nozzle is reduced, and the mutual operation is stabilized. Is possible.

In the above invention, a suction control device that controls the suction mechanism so as to start suction at the same time or before the suction nozzle that performs the movement arrives at the needle hole of the needle plate may be provided. .
In the above invention, dust can be collected around the needle hole by the suction nozzle, and the lower region of the needle plate can be maintained more cleanly.

  Moreover, in the said invention, it is good also as a structure which forms the surrounding part of the said needle hole of the upper surface of the said lower needle plate higher than the other part of the upper surface of the said lower needle plate.

Further, Oite to the invention, the the fixed knife and the moving knife are both through holes and the lower yarn and the upper yarn is inserted is formed, most of the cutting operation direction of the through hole of the moving knife The small width may be the same as the width in the cutting operation direction of the needle hole of the upper needle plate.

  Moreover, in the said invention, it is good also as a structure provided with the intermediate presser for preventing attraction | suction to the said button side of the said to-be-sewn material between the said button hold | maintained at the time of sewing, and the to-be-sewn material.

  As described above, according to the present invention, the remaining ends of the upper thread and the lower thread can be made shorter.

It is a schematic block diagram of the sewing machine which is 1st embodiment of this invention. It is a block diagram of the control system of a sewing machine. It is a front view which shows the structure of a part of feed adjustment mechanism. It is a perspective view which shows schematic structure of a thread trimming apparatus. It is a top view which shows the thread | yarn cutting state by the moving knife for thread cutting and the fixed knife for thread cutting of a thread cutting device. It is a perspective view of a needle plate. It is a top view of the lower plate of a needle plate and a remaining end excision mechanism. It is a bottom view (standby position state) of the upper plate of the needle plate and the remaining end excision mechanism. It is a bottom view (cutting position state) of the upper plate of the needle plate and the remaining end cutting mechanism. It is a perspective view of a remaining end excision mechanism. It is a perspective view of the remaining end cutting mechanism seen from the direction different from FIG. It is a rear view of a suction mechanism. FIG. 13A is an explanatory diagram showing a state after the sewing thread is cut when the 0 pitch control is performed. FIG. 13B is an explanatory view showing a state after the sewing thread is cut when the 0 pitch control is not performed. FIG. 14A is an explanatory view showing the length after excision of the remaining suture thread when the feed dog lowering control is not performed. FIG. 14B is an explanatory view showing the length after excision of the remaining suture thread when the feed dog lowering control is performed. 4 is a timing chart showing a flow of sewing control of the sewing machine. It is a bottom view which shows the other example of a thread trimming apparatus. It is a perspective view which shows the other example of a remaining end cutting mechanism. FIG. 18A is an explanatory view showing a state before the remaining end excision by another remaining end excision mechanism. FIG. 18B is an explanatory view showing a state after the remaining end excision by another remaining end excision mechanism. It is the top view which omitted the needle plate which shows other examples of a remaining end excision mechanism and a suction mechanism, and is in the state before remaining end excision and before the start of suction. It is a top view which omitted a needle plate which shows other examples of a remaining end excision mechanism and a suction mechanism, and shows a state before the remaining end excision and after the start of suction. It is a top view which omitted the needle plate which shows other examples of a remaining end excision mechanism and a suction mechanism, and shows the state after the remaining end excision and after the start of suction. It is a flowchart which shows the operation | movement control from sewing to thread trimming and remaining end cutting. It is a schematic block diagram of the sewing machine which is 2nd embodiment of this invention. FIG. 24 is a block diagram of a control system of the buttoned sewing machine of FIG. 23. It is a disassembled perspective view which shows an upper thread holding | maintenance apparatus. It is the perspective view which looked at the upper thread holding | maintenance apparatus from the bottom. It is a top view for demonstrating the "initial position" of each member which comprises a clamping means, a drive means, and a detection means. It is a side view for demonstrating "initial position" of each member which comprises a clamping means, a drive means, and a detection means. It is a perspective view for demonstrating the "initial position" of a clamping means. It is a top view for demonstrating the "intermediate holding position" of each member which comprises a clamping means, a drive means, and a detection means. It is a side view for demonstrating the "intermediate holding position" of each member which comprises a clamping means, a drive means, and a detection means. It is a top view for demonstrating "standby position" of each member which comprises a clamping means, a drive means, and a detection means. It is a side view for demonstrating "standby position" of each member which comprises a clamping means, a drive means, and a detection means. It is a perspective view for demonstrating the "standby position" of a clamping means. It is a flowchart of the button sewing sewing operation | movement of the button attachment sewing machine of FIG. It is operation | movement explanatory drawing of the button sewing sewing operation | movement of the button attachment sewing machine of FIG. It is operation | movement explanatory drawing of the button sewing sewing operation | movement following FIG. FIG. 35 is an operation explanatory diagram of button sewing operations following FIG. 34. FIG. 36 is an operation explanatory diagram of a button sewing operation following FIG. FIG. 37 is an operation explanatory diagram of a button sewing operation following FIG. 36. It is a perspective view which shows the other example of the shape around a needle hole. It is sectional drawing which showed the fixed hole for cutting of the needle hole and the remaining end excision mechanism, and the moving knife for cutting in a section along the YZ plane passing through the center line of the needle hole. Indicates the time of excision. It is sectional drawing which showed the fixed knife for cutting of the needle hole and the remaining end cutting mechanism, and the moving knife for cutting in a section along the YZ plane passing through the center line of the needle hole, and cutting the moving knife for cutting Indicates operation. It is a perspective view of a feed mechanism provided with an intermediate presser. FIG. 41A is an explanatory view showing a sewing state of the button and the fabric when the intermediate presser is provided. FIG. 41B is an explanatory view showing a sewing state of the button and the fabric when the intermediate presser is not provided.

[First embodiment: Overall schematic configuration of a lockstitch machine]
Hereinafter, embodiments of the present invention will be described in detail with reference to FIGS. FIG. 1 is a schematic configuration diagram of a sewing machine 10 according to the present embodiment, and FIG. 2 is a block diagram of a control system.
The sewing machine 10 is a so-called lockstitch sewing machine, in which the sewing machine frame 20, a needle vertical movement mechanism 30 that moves the needle bar 12 that holds the sewing needle 11 up and down, and a needle drop position of the sewing machine bed portion 21 of the sewing machine frame 20 are provided. The provided needle plate 40, the hook mechanism 50 that entangles the upper thread U of the sewing needle 11 with the lower thread D on the lower side of the needle plate 40, and the movement of feeding the workpiece to be sewn on the upper surface of the needle plate 40 at a constant feed pitch. A feed mechanism 60 as a mechanism, a feed adjusting mechanism 70 for changing the feed pitch, a thread trimming device 80 for cutting the upper thread U and the lower thread D after the needle drop of the final needle, and a sewing needle for the upper thread U after the cutting A wiper mechanism 90 for pulling out the side portion U1 above the sewing product, a remaining end cutting mechanism 100 for cutting off the remaining ends of the upper thread U and the lower thread D of the sewing product after being cut by the thread trimmer 80, and a needle plate Suction is performed from below 40 needle holes 411 and 421. A pull mechanism 110, and a control unit 120 for controlling operations of the respective components.
Note that the thread tension device and the balance are well-known mechanisms mounted on the entire sewing machine, and thus illustration and detailed description thereof are omitted.
Hereafter, each said structure is demonstrated in order.

[Sewing frame]
The sewing machine frame 20 extends along the sewing machine bed part 21 from the upper part of the sewing machine bed part 21, the sewing machine standing part 22 raised upward from one end part of the sewing machine bed part 21, and the sewing machine bed part 21. The sewing machine arm portion 23 extends in this manner.
Here, in describing the configuration of the sewing machine 10, a vertical movement direction of a needle bar 12 to be described later is a Z-axis direction, which is a direction perpendicular to the Z-axis direction and parallel to the longitudinal direction of the sewing machine bed portion 21 and the sewing machine arm portion 23. The direction is the Y-axis direction, and the direction orthogonal to both the Z-axis direction and the Y-axis direction is the X-axis direction. In addition, when the sewing machine 10 is installed on a horizontal plane, the Z-axis direction is a vertical vertical direction, and the X-axis direction and the Y-axis direction are horizontal directions.

Inside the sewing machine arm portion 23, a main shaft 32 directed parallel to the longitudinal direction (Y-axis direction) is rotatably supported.
Further, on the inner side of the sewing machine bed portion 21, a vertical feed shaft 61 directed in parallel to the longitudinal direction (Y-axis direction) is rotatably supported.
Each of the main shaft 32 and the vertical feed shaft 61 is fixedly equipped with sprockets 33 and 62, and torque is transmitted from the main shaft 32 to the vertical feed shaft 61 via a toothed belt 63.

[Needle vertical movement mechanism]
As shown in FIG. 1, the needle up-and-down moving mechanism 30 includes a sewing machine motor 31 including a servo motor provided on the upper portion of the sewing machine standing body 22, and a main shaft 32 that rotates by being connected to an output shaft of the sewing machine motor 31. A needle bar crank 34 fixedly provided at an end of the main shaft 32 on the sewing machine surface side, a crank rod 35 having one end connected to a position eccentric from the rotation center of the main shaft 32 in the needle bar crank 34, a needle The needle bar 12 is connected to the other end portion of the crank rod 35 through a bar holder 36.
The needle bar 12 holds the sewing needle 11 at its lower end, and is supported by the sewing machine arm 23 so as to be capable of reciprocating up and down along the Z-axis direction.
The sewing machine motor 31 is a servo motor and includes an encoder 37 (see FIG. 2). Then, the control device 120 detects the rotation speed, the spindle angle, and the like of the sewing machine motor 31 from the encoder 37, and performs operation control on the sewing machine motor 31.
The configurations of the needle bar crank 34, the crank rod 35, the needle bar holder 36, etc. are the same as known ones, and therefore detailed description thereof is omitted.

[Feed mechanism]
Since the feed mechanism 60 is the same as a well-known structure, detailed description is abbreviate | omitted. That is, the feed mechanism 60 has feed teeth 64 that feed and sew a workpiece at a fixed feed pitch along the X-axis direction by letting the tips of the teeth protrude and retract from the intrusion holes 412 and 422 formed in the needle plate 40 (FIG. Reference), a feed base for supporting the feed dog 64, a vertical feed shaft 61 for giving the feed base a vertical reciprocation, a horizontal feed shaft for giving the feed base a horizontal reciprocation along the X-axis direction, A cam crank mechanism that converts the full rotation of the vertical feed shaft 61 into a reciprocating motion in the vertical direction and transmits it to the feed base, and converts the full rotation of the vertical feed shaft 61 into a reciprocating rotational motion and transmits it to the horizontal feed shaft. One cam crank mechanism and a horizontal feed arm fixed to the horizontal feed shaft and imparting a horizontal reciprocating motion to the feed base are provided.
The feed table is given a reciprocating motion in the vertical direction from one end thereof, and is given a reciprocating motion in the horizontal direction from the other end. The reciprocating motion in the vertical direction and the reciprocating motion in the horizontal direction are both applied at the same cycle as the rotation of the sewing machine motor 31. As a result, the feed dog 64 positioned in the middle of the feed base is synthesized and substantially Perform a circular motion with an elliptical trajectory. When the upper part of the ellipse motion is moved, the tip of the feed dog 64 protrudes from the intrusion hole of the needle plate 40, and the operation of feeding the workpiece along the longitudinal direction of the ellipse is performed. .

[Feed adjustment mechanism]
The feed adjusting mechanism 70 is transmitted to the horizontal feed shaft according to the inclination angle between the cam crank mechanism that transmits the reciprocating rotation operation from the vertical feed shaft 61 to the horizontal feed shaft in the feed mechanism 60 and the horizontal feed shaft. A feed adjusting body (not shown) that switches between the amplitude and phase of the reciprocating rotation angle.
The feed adjusting body of the feed adjusting mechanism 70 has a tilt angle at which the feed pitch becomes 0, and the feed pitch in the forward feed direction can be greatly adjusted as the tilt angle increases in a certain direction from that angle. As the tilt angle increases in the reverse direction, the feed pitch in the reverse feed direction can be adjusted to be larger.

  As shown in FIGS. 2 and 3, the feed adjusting mechanism 70 is supported by a dial (not shown) for setting and inputting a feed pitch, and is rotatably supported in the sewing machine standing body 22, and according to the setting of the dial. The cam member 71 whose rotation angle changes, the feed adjusting shaft 77 whose one end is connected to the dial and the other end is in contact with the cam member, the connecting rod 72 connecting the cam member 71 and the feeding adjusting body, and the connecting rod The feed adjusting body is angle-adjusted so that the pitch of the condensation sewing is smaller than the feed pitch set by the dial via the connecting rod 72 and the lever arm 73, and a feed adjusting spring (not shown) that urges 72 downward. Air cylinder 74 for condensation, air cylinder 75 for 0 pitch for changing the inclination angle of the feed adjusting body so that the feed pitch becomes 0, and the feed set by the dial And a reverse feed solenoid 76 for switching the inclination angle of the adjuster feed so that the feeding direction while maintaining the width of the feed pitch of the pitch or condensation sewing a positive direction and reverse direction.

In the case of the feed adjustment mechanism 70 shown in FIG. 3, the adjustment shaft 77 is moved forward and backward by the dial (in the X-axis direction in FIG. 3) to adjust the contact position with the cam member 71. By adjusting the tilt angle of the feed adjuster, the feed pitch during normal sewing is adjusted.
Note that the feed adjusting body and the mechanism for adjusting the angle of the feed adjusting body are well-known techniques, and, for example, use the principle of feed adjustment described in JP-A-2007-202667 and JP-A-2011-101719. be able to.

The operations of the condensation air cylinder 74 and the 0-pitch air cylinder 75 are controlled by the control device 120 via an electromagnetic valve (not shown).
As shown in FIG. 3, the condensation air cylinder 74 sucks the plunger (moves in the right direction in FIG. 3) and rotates the lever arm 73 in the clockwise direction (in FIG. 3). Against this, the connecting rod 72 is rotated in the clockwise direction (in FIG. 3), and the inclination angle of the feed adjusting body is adjusted so that the pitch of the condensation sewing is obtained. The 0-pitch air cylinder 75 advances the plunger (moves leftward in FIG. 3), and pushes back the lever arm 73 rotated by the condensation air cylinder 74 in the counterclockwise direction, whereby the connecting rod 72 is counterclockwise. Rotate in the direction and adjust the tilt angle of the feed adjuster so that it becomes 0 pitch. Because of the above structure, when the feed is set to 0 pitch, the suction operation of the condensation air cylinder 74 and the advance operation of the 0 pitch air cylinder 75 are always executed in combination.
In the case of the feed adjusting mechanism 70 shown in FIG. 3, the connecting rod 72 is rotated clockwise (in FIG. 3) by the suction operation of the condensation air cylinder 74, and the tilt of the feed adjusting body at this time The angle is reverse feed stitching at the pitch of condensation stitching.

[Wiper mechanism]
The wiper mechanism 90 is the same as a well-known one, and a detailed description thereof is omitted. The wiper mechanism 90 includes a wiper 91 supported so as to be rotatable around the X axis at a position adjacent to the needle bar 12 at a lower end of the sewing machine arm portion 23, and a wiper that imparts a rotating operation to the wiper 91. And a solenoid 92.
The lower end portion of the wiper 91 is formed in a hook shape, and the lower end portion of the wiper 91 is equipped so as to pass under the sewing needle 11 at the upper stop position by turning. As a result, the sewing needle side portion U1 of the upper thread U cut by the thread trimming device 80 on the lower side of the needle plate 40 can be pulled out onto the workpiece.

[Hook mechanism]
The hook mechanism 50 is a well-known vertical full-rotation hook, and includes an inner hook that houses a bobbin with a lower thread D wound inside, and an outer hook that rotates on the outer periphery of the inner hook and captures the upper thread U from the sewing needle 11. A hook and a hook shaft 51 for applying a rotational force to the outer hook are provided.
The shuttle shaft 51 is supported in the sewing machine bed portion 21 so as to be parallel and rotatable with the above-described vertical feed shaft 61, and reverse rotation is transmitted between the vertical feed shaft 61 and the vertical feed shaft 61 at a double speed through a gear. ing. That is, the outer hook of the hook mechanism 50 rotates at a double speed of the main shaft 32.
Further, the inner hook and the outer hook are arranged below the needle plate 40 and are designed so that the sword tip of the outer hook passes under the needle holes 411 and 421 formed in the needle plate 40.

[Thread trimming device]
As shown in FIG. 4, the thread trimming device 80 cooperates with the thread trimming moving knife 81 and the thread trimming fixed knife 82 for cutting the upper thread U and the lower thread D, and the thread is driven by the sewing machine motor 31 as a drive source. An operating mechanism in which the moving knife 81 for cutting and the fixed knife 82 for thread cutting move along the outer periphery of the outer hook of the hook mechanism 50 in a direction in which the blade portions 81a and 82a abut against each other; an operating mechanism and a sewing machine motor A thread trimming solenoid 83 (see FIG. 2) is provided for switching between connection and disconnection of power transmission with the motor 31.
The thread trimming device 80 can use, for example, a well-known configuration disclosed in Japanese Patent Application Laid-Open No. 7-145589, and a detailed description thereof is partially omitted.

When the cutting operation is performed, the thread cutting fixed knife 82 is moved forward by the operating mechanism to the vicinity of the needle passing position below the needle hole 421 and stands by.
On the other hand, the thread-cutting knife 81 moves from the opposite side of the thread-cutting knife 82 across the needle passage position below the needle hole 421 in a direction facing the forward direction of the thread-cutting knife 82, The blade 81a moves so as to pass the needle passage position below the needle hole 421. As a result, the upper thread U and the lower thread D are sandwiched between the blade portions 81a and 82a at the needle passing position below the needle hole 421 and cut.

FIG. 5 shows the shape around the blade portion 81a of the moving knife 81 for thread cutting. As shown in the drawing, the thread-cutting knife 81 has a scooping portion 81b that is sharp in the forward direction during the cutting operation, and first and second recesses 81c and 81d formed on both sides of the scooping portion 81b. It has.
When the needle portion 81b passes through the needle passage position below the needle hole 421, it rushes into the loop of the upper thread U that is pulled out below the needle plate 40 by the outer hook, and the upper thread U is inserted into the portion on the sewing needle side. Sorting is performed on U1 and the portion U2 to be sewn. As a result, the sewing needle side portion U1 of the upper thread U is sorted into the first recess 81c, and the workpiece side portion U2 and the lower thread D are sorted into the second recess 81d.
A blade portion 81 a is formed at the inner edge of the second recess 81 d of the thread-cutting knife 81, and the blade portion 82 a of the thread-cutting knife 82 is a second part of the thread-cutting knife 81. Is formed so as to face only the recess 81d side. For this reason, only the to-be-sewn product side portion U2 and the lower thread D selected in the second recess 81d are cut.

  The actuating mechanism is capable of reciprocating and rotating from the individual support members for individually supporting the thread cutting scalpels 81 and 82 concentrically with the shuttle shaft 51 and the clutch motor and cam mechanism from the sewing machine motor 31. A female shaft that is transmitted, and a plurality of link bodies that impart rotational motions in the opposite directions to the individual supports from the female shaft. Further, switching between connection and disconnection of power from the sewing machine motor 31 to the female shaft in the clutch mechanism is performed by the thread trimming solenoid 83 described above.

[Needle plate]
The needle plate 40 is provided above the sewing machine bed portion 21 and below the needle bar 12. As shown in FIG. 6, the needle plate 40 has a two-layer structure composed of an upper plate 41 and a lower plate 42.
Each of the upper plate 41 and the lower plate 42 is a semi-elliptical plate body, and the lower plate 42 is fitted into a recess 413 formed on the lower surface side of the upper plate 41 and integrated by screwing.
In the integrated state, the upper plate 41 and the lower plate 42 are formed with needle holes 411 and 421 and protruding and retracting holes 412 and 422 of the feed dog 64 (see FIG. 10) at the same position.

  Needle holes 411 and 421 are formed at positions immediately below the sewing needle 11, and there are two retracting holes 412 and 422 of the feed dog 64 on the same line along the X-axis direction with respect to the needle holes 411 and 421. Furthermore, two in total are formed on both sides. Each of the protrusion holes 412 and 422 has a slit shape along the feed direction of the workpiece, and has a structure that allows the tip of the feed dog 64 to move in the feed direction.

[Residual edge excision mechanism]
As shown in FIGS. 7 to 11, the remaining end excision mechanism 100 is a fixed scalpel for excision as a scalpel built in between an upper plate 41 serving as an upper layer of the needle plate 40 and a lower plate 42 serving as a lower layer. 101, a cutting moving knife 102, a thread cutting air cylinder 103 for operating the cutting knife 102, and a knife operating arm 105 having one end connected to a plunger of the thread cutting air cylinder 103 via a knuckle 104. And.

FIG. 7 is a plan view of the lower plate 42, and FIG. 8 is a bottom view of the upper plate 41.
In order to insert the excision fixing knife 101 and the excision moving knife 102 on the lower surface of the upper plate 41 and the upper surface of the lower plate 42, the needle holes 411, 421 and the feed dogs 64 are provided around the retracting holes 412, 422. Concave portions 414 and 424 are formed.
The excision fixing knife 101 is disposed in the concave portion 414 of the upper plate 41 with its longitudinal direction aligned with the X-axis direction. Further, the proximal end portion of the fixing knife 101 for excision is fixedly supported by screwing into a concave portion 414 formed on one end portion side of the intrusion hole 412 on the lower surface of the upper plate 41, and a needle hole is formed from the proximal end portion. An extending portion that extends farther than the needle hole 411 toward the 411 side is formed. Further, a through hole for passing the sewing needle 11 is formed at a position corresponding to the needle hole 411 at the distal end of the extending portion of the fixing knife 101 for excision, and the portion near the distal end at the inner edge of the through hole is a thread excision. It becomes the blade part 101a for performing.
Further, almost the entire cutting scalpel 101 is formed with a narrow width so as not to interfere with the feed dog 64 that performs the retracting operation from the retracting hole 412, and an elongated hole 101 b is formed.

The excision moving knife 102 is disposed in the concave portion 424 of the lower plate 42 with its longitudinal direction aligned with the X-axis direction. In addition, a long hole 425 that penetrates vertically is formed in the concave portion 424 formed on the other end side of the intrusion hole 422 of the lower plate 42, and the pin 105 a (see FIG. 10) is inserted from below.
An insertion hole 102 a into which the pin 105 a of the knife operating arm 105 is inserted is formed at the base end of the excision moving knife 102. In addition, an extending portion is formed that extends from the proximal end portion of the excision moving knife 102 toward the needle hole 421 side farther than the needle hole 421. Further, the excision moving knife 102 is formed with an elongated hole 102b over almost the entire length from the proximal end portion to the vicinity of the distal end of the extending portion. At the distal end side of the elongated hole 102b, the sewing needle 11 passing through the needle hole 421 can be passed. Further, the tip side portion of the inner edge portion of the elongated hole 102b is a blade portion 102c for performing thread cutting.
A guide pin 415 protruding downward from the lower surface of the upper plate 41 is inserted into the elongated hole 102 b of the excision moving knife 102. This guide pin 415 is for stabilizing the reciprocating motion of the excision moving knife 102 when the excision moving knife 102 is reciprocated in the X-axis direction by a knife operating arm 105 described later.
Further, almost the entire excision moving knife 102 is formed to be narrow so as not to interfere with the feed dog 64 that performs the retracting operation from the retracting hole 412.

Further, the extending end of the excision fixing knife 101 overlaps the extending end of the excision moving knife 102 from above, and the blade 101a of the excision fixing knife 101 The cutting blade 102c of the excision moving knife 102 is disposed so as to face each other with the needle holes 411 and 421 interposed therebetween.
Then, as shown in FIG. 9, the excision moving knife 102 is given an operation of pulling in the direction away from the excision fixing knife 101 by the knife operating arm 105 from the state in which the blade portions 101a and 102c face each other. Thus, after the cutting by the thread trimmer 80, the remaining ends of the upper thread U and the lower thread D in the needle holes 411 and 421 can be cut off.

As shown in FIGS. 10 and 11, the knife operating arm 105 and the yarn cutting air cylinder 103 are supported by a sliding plate 13 provided adjacent to the needle plate 40 in the sewing machine bed portion 21. In FIG. 10, the upper plate 41 of the needle plate 40 is not shown.
The knife operating arm 105 is rotatably supported by a stepped screw 106 attached to the lower surface side of the sliding plate 13 in the middle in the longitudinal direction, and one end of the knife operating arm 105 serves as a plunger of the thread cutting air cylinder 103. They are connected via a knuckle 104.
The other end of the knife operating arm 105 is provided with a pin 105a protruding upward, and the pin 105a is inserted into the insertion hole 102a of the excision moving knife 102 as described above.
The thread cutting air cylinder 103 can apply a pivoting action to the knife operating arm 105 by a forward and backward movement of the plunger, and gives a cutting action to the moving knife 102 for cutting by moving the plunger forward from the retracted state. It is like that.

[Suction mechanism]
As shown in FIG. 12, the suction mechanism 110 is disposed adjacent to the shuttle mechanism 50 in the sewing machine bed portion 21. The suction mechanism 110 includes a suction nozzle 111 and a nozzle moving air cylinder 113 as nozzle driving means for reciprocating a support 112 that supports the suction nozzle 111 in a predetermined direction.
The suction mechanism 110 performs suction from the lower side of the needle hole 421 so that when the remaining ends of the upper thread U and the lower thread D are cut, the remaining ends are extended downward so that the cutting is performed more reliably. The purpose is to collect the remaining end after excision.

The upper end of the suction nozzle 111 is opened to form a suction port, and the lower end of the suction nozzle 111 is connected to a negative pressure generation source via a dust trap (not shown). In addition, a suction electromagnetic valve 114 (see FIG. 2) is provided between the trap of the suction nozzle 111 and the negative pressure generation source, so that the start and stop of suction can be switched.
Further, the upper end portion of the suction nozzle 111 is formed in a curved shape along the outer periphery of the outer hook so as to avoid the hook mechanism 50 and to be close to the needle hole 421 of the needle plate 40.

The support body 112 that supports the suction nozzle 111 is supported so as to be movable in the horizontal direction in the sewing machine bed portion 21, and the upper end portion of the suction nozzle 111 is separated from the needle hole 421 of the needle plate 40 from the needle hole 421. It is possible to move to the vicinity of the position immediately below.
The nozzle moving air cylinder 113 moves the suction nozzle 111 forward and backward according to the moving range of the support 112. As a result, the suction nozzle 111 can reciprocate from the retracted position separated from the needle hole 421 of the needle plate 40 to the suction position where the upper end portion approaches to a position immediately below the needle hole 421. .

[Sewing machine control system]
As shown in FIG. 2, the control device 120 includes a ROM 122 that stores and stores various programs for various processes such as control and determination, a CPU 121 that performs various arithmetic processes according to these various programs, and a work memory for various processes. A RAM 123 to be used and an EEPROM 124 storing various sewing data and setting data are roughly configured.
The control device 120 is connected to the sewing machine motor 31 and the encoder 37 of the needle up-and-down movement mechanism 30, the reverse feed solenoid 76 of the feed adjustment mechanism 70, the condensation air cylinder 74, and the 0 pitch via the system bus and the drive circuit. Air cylinder 75, thread trimming solenoid 83 of thread trimming device 80, air cylinder 103 for thread trimming of remaining end cutting mechanism 100, wiper solenoid 92 of wiper mechanism 90, suction solenoid valve 114 of suction mechanism 110, and nozzle moving air A cylinder 113 and the like are connected.
Note that the air cylinder 74 for condensation, the air cylinder 75 for 0 pitch, the air cylinder 103 for thread cutting, and the air cylinder 113 for moving the nozzle are actually controlled by the control device 120 with respect to the electromagnetic valves that operate them. However, illustration of each solenoid valve is omitted here.
Although the sewing machine motor 31 is controlled via a driver circuit, its illustration is also omitted.

Further, the control device 120 is connected to an operation input unit 125 for inputting various settings related to sewing and a pedal 126 as signal input means for executing sewing.
The operation input unit 125 sets, for example, whether or not to perform condensation sewing, which will be described later, the condensation pitch, the number of stitches, and the forward and reverse sewing directions.
The pedal 126 instructs the control device 120 to input a sewing start signal when the front foot is depressed, a sewing stop signal when the front foot is released, and a thread trimming signal when the rear foot is depressed. In addition, when condensation sewing is set, when the pedal 126 is stepped down, the thread trimming is executed after the condensation sewing is executed.

[0 pitch control]
Here, various controls performed by the control device 120 when sewing is stopped will be described.
First, the control device 120 executes the thread trimming operation when the signal input by the stepping on the pedal 126 is detected. At this time, the control device 120 controls the feed mechanism 60 so that the needle drop position of the final needle for executing the thread trimming by the thread trimming device 80 is the same (or substantially the same) as the needle drop position immediately before that. And the feed pitch is 0.

As shown in FIG. 13B, when the thread is cut by the thread trimming device after feeding to the final needle at a normal feed pitch or condensation pitch as in the prior art, no knot is formed at the needle drop of the final needle as shown in FIG. 13B. The remaining end of the upper thread U remaining on the sewing product hangs down from the needle drop position of the final needle, and the remaining end of the lower thread D remaining on the sewing product hangs down from the previous needle drop position separated by 1 pitch. .
On the other hand, when the 0 pitch control is performed, as shown in FIG. 13A, the knot does not occur in the final needle, but the upper thread U and the lower thread D are suspended from the same needle drop position. It is possible to avoid a state in which the remaining end hangs down from the previous needle drop position. Further, it is possible to prevent the remaining end from becoming longer by the length of the feed mechanism 60 that has sent the sewing product between the needle drop immediately before one stitch and the thread cutting.

[Feed dog lowering control]
Further, the control device 120 reduces the protruding amount of the feed dog 64 from the upper surface of the needle plate 40 when the lower thread D and the upper thread U are cut by the thread trimming device 80 by rotating the sewing machine motor 31, and then removes the remaining end. Feed dog lowering control is performed so that the lower ends of the lower thread D and the upper thread U are cut by the mechanism 100.
14A and 14B, the symbol h indicates the position of the excision surface by the excision fixing knife 101 and the excision moving knife 102 inside the needle plate 40.
The thread trimmer 80 cuts the upper thread U and the lower thread D at a main shaft angle of 50 ° (so-called upper stop position, where the needle bar top dead center is 0 °). FIG. 14A shows the protruding state of the feed dog 64 at a main shaft angle of 50 °. When the remaining end excision mechanism 100 performs the remaining end cutting of the upper thread U and the lower thread D in this state, the final remaining end length L1 after the cutting is determined by the distance between the feed dog 64 projecting from the needle plate upper surface and the needle. The total length is the distance from the upper surface of the plate to the excision surface of each excision knife 101, 102.
The control device 120 drives the sewing machine motor 31 between the cutting of the upper yarn U and the lower yarn D by the yarn trimming device 80 and the execution of the remaining end cutting by the remaining end cutting mechanism 100 so that the main shaft angle is changed from 50 °. Rotate forward up to 95 °.
As a result, as shown in FIG. 14B, the amount of protrusion of the feed dog 64 from the upper surface of the needle plate 40 can be made substantially zero, so that the final ends of the upper thread U and the lower thread D after the remaining ends are cut off. It is possible to reduce the typical remaining end length L2 to a length substantially equal to the distance from the upper surface of the needle plate to the resection surface by the resection scalpels 101 and 102.

[Nozzle drive control]
Further, the control device 120 moves the upper end of the suction nozzle 111 from the retracted position away from the needle holes 411 and 421 of the needle plate 40 to the position immediately below the needle holes 411 and 421 before the remaining end excision mechanism 100 starts to perform excision. The nozzle drive control is performed to bring the suction nozzle 111 into the suction state from the start of the movement of the suction nozzle 111 to at least the completion of the cutting of the remaining end cutting mechanism 100.

As a result, the suction nozzle 111 can collect not only the remaining ends of the cut upper thread U and lower thread D but also the dust around the moving range of the suction nozzle 111, It becomes possible to achieve cleaning. Further, the suction ends of the upper thread U and the lower thread D by the remaining end cutting mechanism 100 are started simultaneously with or before the suction nozzle 111 reaches the position immediately below the needle holes 411 and 421 of the needle plate 40. Since the suction is started before the cutting, the remaining ends of the cut upper thread U and lower thread D can be collected without being taken out.
Further, the remaining ends of the upper thread U and the lower thread D can be extended downward when being cut, and the remaining ends of the upper thread U and the lower thread D can be more reliably cut by the remaining end cutting mechanism 100. Is possible.

[Flow of sewing control of sewing machine]
The flow of operation control from sewing of the sewing machine 10 to thread trimming and remaining end cutting will be described with reference to the timing chart of FIG. 15 and the flowchart of FIG. Here, it is assumed that condensation sewing is set at the end of sewing. In addition, (lower) in FIG. 15 has shown the lower stop position in a spindle angle, (upper) has shown the upper stop position.

  First, when the front depression signal input of the pedal 126 is detected (step S1), the control device 120 starts driving the sewing machine motor 31 (step S3). The feed pitch at the time of this normal sewing is operated by the feed mechanism 60 at the feed pitch set by the dial of the feed adjusting mechanism 70.

  Then, when the front depression state of the pedal 126 is released and the thread trimming signal input is detected by the rear depression (step S5), the control device 120 waits for the spindle angle 220 ° to be detected by the encoder 37. (Step S7), the condensation air cylinder 74 is actuated in the direction in which the plunger moves backward (timing T1) (Step S9). Thereby, the feed adjusting body of the feed adjusting mechanism 70 is set to the inclination angle that becomes the set condensation pitch.

Then, when the last needle drop is performed for a predetermined number of stitches of condensation sewing set in advance (step S11), the control device 120 waits for the spindle angle 220 ° to be detected again by the encoder 37 (step S13). ), The 0-pitch air cylinder 75 is operated in the direction in which the plunger advances (timing T2) (step S15).
As a result, the feed adjusting body of the feed adjusting mechanism 70 is set to an inclination angle of 0 pitch, and the needle drop at the next final needle is performed at the same position as the last needle drop of the condensation stitch (step S17).

Next, after the needle drop of the last needle, when the main shaft angle 220 ° is detected again by the encoder 37 (step S19), the control device 120 operates the thread trimming solenoid 83 of the thread trimming device 80 to perform thread trimming. The power transmission between the operating mechanism of the device 80 and the sewing machine motor 31 is switched to the connected state (timing T3) (step S21).
As a result, the upper thread U is sorted into the sewing needle side portion U1 and the workpiece side portion U2 by using the thread cutting knife 81 of the thread trimming device 80 as a reference. By the cooperation of 81 and the thread-cutting fixing knife 82, the portion U2 to be sewn of the upper thread U and the lower thread D are cut (step S23).

Thereafter, the driving of the sewing machine motor 31 is stopped at a main shaft angle of 50 ° (timing T4) (steps S25 and S27), and the control device 120 waits 120 [msec] after the main shaft angle of 50 ° is detected by the encoder 37. After waiting (step S29), the thread trimming solenoid 83 is stopped (step S31), and the power transmission between the operating mechanism of the thread trimming device 80 and the sewing machine motor 31 is switched to a cut-off state (timing T5).
Further, at the timing T5, the control device 120 operates the wiper solenoid 92 of the wiper mechanism 90 to rotate the wiper 91 (step S33). Thereby, the sewing needle side portion U1 of the upper thread U extending from the sewing needle 11 to the sewing product can be pulled out above the sewing product.

  Then, the control device 120 operates the nozzle moving air cylinder 113 at the timing when the operation of the wiper solenoid 92 is completed, and moves the suction nozzle 111 from the standby position toward the position directly below the needle holes 411 and 421 (timing T6). ). Further, the suction electromagnetic valve 114 is opened at the same timing, and suction is started simultaneously with the start of movement of the suction nozzle 111 (step S35).

Thereafter, the suction nozzle 111 reaches a position immediately below the needle hole 421 after a lapse of a specified time, and at this timing, the control device 120 drives the sewing machine motor 31 (timing T7) (step S37) and the spindle angle is 95. The driving of the sewing machine motor 31 is continued until it reaches ° (timing T8).
Thereby, the front-end | tip part of the feed dog 64 which protruded from the upper surface of the needle plate 40 descend | falls, and it will be in the state which was almost hidden.

Then, when the spindle angle of 95 ° is detected (step S39), the control device 120 stops driving the sewing machine motor 31 (step S41), and the yarn cutting air cylinder of the remaining end cutting mechanism 100 is almost immediately stopped. 103 is operated (step S43), and the excision operation by the excision moving knife 102 is started. As a result, the remaining ends of the upper thread U and the lower thread D are cut off, and the remaining ends cut off by the lower suction nozzle 111 are sucked.
When the yarn cutting air cylinder 103 is operated for a specified time, the operation is stopped and the cutting knife 102 is moved backward (timing T9).

Thereafter, the control device 120 closes the suction electromagnetic valve 114 to stop the suction state of the suction nozzle 111 (step S45) and drives the sewing machine motor 31 in reverse rotation (timing T10) (step S47).
When the main shaft angle is returned to 50 ° (step S49), the driving of the sewing machine motor 31 is stopped (timing T11) (step S51). Further, at the same timing, the control device 120 moves the plunger of the condensation air cylinder 74 forward, moves the plunger of the zero pitch air cylinder 75 and the nozzle movement air cylinder 113 backward, and returns to the standby position (step S53). .
Thereby, the sewing control of the sewing machine by the control device 120 ends.

[Effect of the embodiment of the invention]
As described above, the sewing machine 10 includes the needle plate 40 through which the needle holes 411 and 421 are inserted and the feed as a moving mechanism that moves the workpiece along the upper surface of the needle plate 40. A mechanism 60, a needle up-and-down moving mechanism 30 that moves the sewing needle 11 up and down, a hook mechanism 50 that catches the upper thread U from the sewing needle 11 below the needle plate 40 and entangles the lower thread D, and a needle plate 40 and the shuttle mechanism 50, and a thread trimming device 80 that cuts a part to be sewn of the loop of the lower thread D and the upper thread U, and a loop of the upper thread U that is cut by the thread trimming apparatus 80. In the sewing machine 10 including the wiper mechanism 90 that pulls out the sewing needle side portion U1 to the upper side of the sewing product, the thread cutting knife 81 or 82 of the thread trimming device 80 is below the upper surface of the upper plate 41 of the needle plate 40. The thread trimming device 8 includes a remaining end cutting mechanism 100 disposed at a higher position. Of after yarn cutting, and cut the remaining end of the lower yarn D and the upper thread U leading to the workpiece by xanthan ablation mechanism 100.
Furthermore, the sewing machine 10 has a needle plate 40 with a two-layer structure on the upper and lower layers of the needle plate 40 between the upper plate 41 and the lower plate 42 on the side of the sewing product cut by the thread trimming device 80. A fixed cutting knife 101 for cutting and a moving knife 102 for cutting are built in as a cutting knife for the remaining end cutting mechanism 100 that cuts the remaining ends of the lower thread D and the upper thread U.

  The sewing machine 10 cuts the part to be sewn of the lower thread D and the upper thread U with the thread trimming device 80, and then further removes the fixed knife 101 and the moving knife for cutting of the remaining end cutting mechanism 100 built in the needle plate. Since the remaining ends of the lower thread D and the upper thread U on the side to be sewn are cut by 102, the remaining ends of the lower thread D and the upper thread U after the cutting process are made shorter than the length corresponding to the thickness of the needle plate 40. It becomes possible.

Further, the sewing machine 10 controls the feed amount of the feed mechanism 60 as a moving mechanism so that the needle drop position of the final needle for executing the thread trimming by the thread trimming device 80 is the same as the needle drop position of the previous needle. A control device 120 that performs 0-pitch control is provided.
For this reason, it is possible to avoid a state in which the remaining ends of the upper thread U and the lower thread D hang from different positions, and it is possible to improve the sewing quality. Furthermore, it can be avoided that the feed length of the sewing material fed by the feed mechanism 60 from the last needle drop to the thread trimming is added to the remaining lengths of the upper thread U and the lower thread D. The remaining ends of the upper yarn U and the lower yarn D cut by the device 80 can be shortened.
The remaining ends of the upper thread U and the lower thread D cut by the thread trimming device 80 are cut shorter by the remaining end cutting mechanism 100, but the upper thread U and the lower thread D after being cut by the thread trimming device 80 are cut off. By shortening the remaining end in advance, it is possible to reduce the amount of waste generated when the remaining end excision mechanism 100 is excised. Further, since the removed remaining end is short, the collection by the suction mechanism 110 can be more reliably performed.

Further, the sewing machine 10 includes a suction mechanism 110 that sucks the remaining ends of the lower thread D and the upper thread U cut off on the lower side of the needle plate 40.
For this reason, the suction mechanism 110 can collect the lower thread and the remaining end of the upper thread on the lower side of the needle plate 40, and can reduce the occurrence of malfunction due to adhering to the surrounding mechanism and the like. It becomes.
Further, the remaining ends of the upper thread U and the lower thread D to be cut by the remaining end cutting mechanism 100 can be sucked and extended downward, so that cutting can be performed more reliably.

The suction mechanism 110 of the sewing machine 10 includes a suction nozzle 111 that can move toward and away from the needle hole 421 of the needle plate 40, and a nozzle moving air cylinder 113 that serves as a nozzle driving means for applying the contact and separation movement operation. I have.
Therefore, the suction nozzle 111 can be retracted during the operation of the feed dog 64, the shuttle mechanism 50, etc., and the interference between these components and the suction nozzle 111 is reduced, and the mutual operation is stabilized. It becomes possible.

Further, the sewing machine 10 includes a control device 120 as a suction control device that controls the suction mechanism 110 so that suction is started before the moving suction nozzle 111 reaches the needle hole 421 of the needle plate 40.
For this reason, dust collection around the moving path of the suction nozzle 111 can also be performed, and the suction operation is performed before the suction nozzle 111 reaches the needle hole 421. In addition, the remaining end of the lower thread D can be stretched and the remaining end after excision can be collected.

Further, in the sewing machine 10, a feed mechanism 60 as a moving mechanism obtains power from the sewing machine motor 31, and feeds the sewing product by feed teeth 64 that protrude and retract from the retracting holes 412 and 422 of the needle plate 40, and the control device 120. The thread trimmer 80 reduces the amount of protrusion of the feed dog 64 from the needle plate 40 when the thread side device U2 of the loop of the lower thread D and the upper thread U is cut by the rotation of the sewing machine motor 31. Feed dog lowering control is performed to cut the remaining ends of the lower thread D and the upper thread U by the end cutting mechanism 100.
For this reason, since the amount of protrusion of the feed dog 64 is reduced and the remaining ends of the lower thread D and the upper thread U are cut off, it is possible to further shorten the remaining ends after the cutting.
In addition, although description is abbreviate | omitted in this application, it is the upper thread clamp apparatus of Unexamined-Japanese-Patent No. 2008-018282 between the start of cutting | disconnection of the upper thread U and the lower thread D by the thread trimming apparatus 80, and the suction start by a suction nozzle. You may make it add the needle thread clamp operation by.

[Other examples of thread trimming devices]
FIG. 16 shows a bottom view of another thread trimming device 80A. A thread trimmer 80A in which a moving knife for thread trimmer and a fixed knife for thread trimmer as shown in FIG. 16 are attached to the needle plate 40A is suitable for a sewing machine equipped with a moving mechanism other than the feed mechanism 60 using the feed dog 64. It is.
The thread trimmer 80A includes a thread trimmer 81A that rotates about the Z axis, and a thread trimmer fixed knife 82A that cooperates with the thread trimmer 81A to cut the upper thread U and the lower thread D. And a plurality of link bodies 83A to 85A that transmit the reciprocating rotation to the thread cutting knife 81A using the sewing machine motor 31 or other actuator as a drive source. Here, a case where a thread trimmer motor 86A (see FIG. 24) independent from the sewing machine motor 31 is illustrated as a drive source for performing a thread trimmer operation by the thread trimmer 81A.
The thread cutting knife 81A is disposed so as to pass below the needle hole 441A by rotation, and on one side edge portion, the sewing needle side portion U1 of the loop of the upper thread U and the side to be sewn. A threading portion 811A and a perforated blade portion 812A that are selectively divided into a portion U2 and a lower thread D are provided, and the other side edge portion captures the portion U2 and the lower thread D on the sewing product side of the upper thread U to capture the yarn. It is a catching portion 813A that carries to the cutting knife 82A.
Further, the thread-cutting fixed knife 82A is provided in the rotation range of the thread-cutting moving knife 81A, and a blade part 821A is formed on one side edge thereof.
When the reciprocating rotation is applied from the drive source to the thread cutting knife 81A, the loop of the upper thread U is caused by the threading portion 811A when passing under the needle hole 441A by the forward rotation. The sewing needle side portion U1 is selected on the inside of the turning radius, and the workpiece side portion U2 and the lower thread D are selected on the outside of the turning radius.
When the moving knife 81A for thread trimming is rotated in the return path, the portion U2 and the lower thread D selected on the outer side of the rotating radius are connected to the other side edge of the moving knife 81A for thread trimming. It is cut around by being sandwiched between the hole part 812A of the thread cutting knife 81A and the blade part 821A of the thread cutting knife 82A.
Such a thread trimmer 80A can also be used in the same manner as the above-described thread trimmer 80.

Further, the thread trimming device 81A is not limited to the configuration in which the thread trimming knife 81A rotates in the horizontal plane, and for example, a thread trimming apparatus including a thread trimming knife that performs a reciprocating linear motion in the horizontal plane. It is also possible to apply.

[Other examples of remnant cutting mechanism and suction mechanism]
Another example of the remaining end excision mechanism and the suction mechanism will be described with reference to FIGS.
The remaining end excision mechanism 100A as another example is suitable for a sewing machine on which a moving mechanism other than the feed mechanism 60 using the feed dog 64 is mounted.
This remaining end excision mechanism 100A includes an excision fixed knife 101A and an excision moving knife 102A as an excision knife built in between an upper plate 41A as an upper layer of a needle plate 40A and a lower plate 42A as a lower layer, A thread cutting air cylinder 103A for operating the cutting knife 102A, and a knife operating member 104A connected to a plunger of the thread cutting air cylinder 103A are provided.

  Both the upper plate 41A and the lower plate 42A of the needle plate 40A are not directly formed with needle holes, and openings 411A and 421A larger than the needle holes are formed at the needle drop positions. A needle hole forming plate 43A in which a needle hole 431A is formed is fixedly mounted to the opening 411A at the needle drop position of the upper plate 41A by screwing. Although not shown in FIG. 17, a needle hole guide 44A (see FIG. 16) in which a needle hole 441A is formed is fixedly mounted to the opening 421A at the needle drop position of the lower plate 42A by screwing. However, the needle plate 40A is substantially the same in function as the needle plate 40 described above.

  The excision fixing knife 101A is attached to the opening 411A of the upper plate 41A, and a through hole through which the sewing needle is inserted is formed at a position where it overlaps with the needle hole 431A, and the inner edge of one end side in the Y-axis direction of the through hole The blade portion 101Aa is formed on.

The excision moving knife 102A is disposed in the recess 422A of the lower plate 42A in a state where the longitudinal direction thereof is along the X-axis direction. The excision moving knife 102A is supported on the lower surface of the upper plate 41A by a step screw 105A so as to be rotatable about the Z axis.
Further, the upper surface of one end of the excision moving knife 102A is in sliding contact with the lower surface of the excision fixing knife 101A, and the one end of the excision moving knife 102A is inserted through the sewing needle at a position where it overlaps with the needle hole 431A. A hole is formed, and a blade 102Aa is formed at the inner edge of the through hole on the other end side in the Y-axis direction.

A through hole 423A penetrating vertically is formed in the recess 422A of the lower plate 42A, and a female actuating member 104A is disposed below the through hole 423A. A boss 104Aa is formed on the upper surface of the knife actuating member 104A, and the boss 104Aa is inserted into the elongated hole 102Ab of the excision moving knife 102A through the through hole 423A.
The thread cutting air cylinder 103A is fixedly installed on the lower surface side of the lower plate 42A with the plunger moving in the Y-axis direction, and the plunger is equipped with a female actuating member 104A. Yes. Thereby, the thread cutting air cylinder 103A rotates the cutting knife 102A via the knife actuating member 104A to move the end portion where the blade 102Aa is formed along the Y-axis direction. It is possible.

  In the normal state, the thread cutting air cylinder 103A is in a state in which its plunger has advanced, and as shown in FIG. 18A, the blade of the cutting knife 101A is sandwiched between the upper thread U and the lower thread D passing through the needle hole 431A. The portion 101Aa and the blade portion 102Aa of the excision moving knife 102A face each other. When the plunger of the thread cutting air cylinder 103A is moved backward, as shown in FIGS. 18B and 21, the cutting knife 102A moves forward toward the blade portion 101Aa side of the cutting knife 101A, The upper thread U and the lower thread D can be cut off by the blade portions 101Aa and 102Aa.

  As shown in FIGS. 19 to 21, the suction mechanism 110 </ b> A is arranged below the needle plate 40 </ b> A in the sewing machine bed portion 21. The suction mechanism 110A includes a suction nozzle 111A and a nozzle moving air cylinder 113A as nozzle driving means for reciprocatingly moving a support arm 112A supporting the suction nozzle 111A in a predetermined direction.

One end of the suction nozzle 111A is opened to form a suction port, and the other end is connected to a negative pressure generating source via a dust collection trap (not shown). The suction nozzle 111A is inclined and supported by the support arm 112A so that the suction port side becomes higher.
In addition, the suction mechanism 110 is the same as the suction mechanism 110 described above in that the suction can be switched between start and stop by a suction electromagnetic valve (not shown).

One end of the support arm 112A supports the suction nozzle 111A, and the other end is connected to a plunger of the nozzle moving air cylinder 113A via a knuckle 115A.
The support arm 112A is supported by the lower surface of the lower plate 42A of the needle plate 40A or a frame of the sewing machine so as to be rotatable about the Z axis, and the suction port of the suction nozzle 111A is separated from the needle hole 431A by the rotation. It is possible to switch the retracted position (position of FIG. 19) and the suction port of the suction nozzle 111A to the vicinity of the position directly below the needle hole 431A (position of FIGS. 20 and 21).
The knuckle 115A and the other end of the support arm 112A are connected to each other through a long hole (not shown) formed in the other end of the support arm 112A.

The remaining end excision mechanism 100A and the suction mechanism 110A can perform the same operation control as the remaining end excision mechanism 100 and the suction mechanism 110 described above.
That is, after the upper thread U and the lower thread D are cut by the thread trimming device, the sewing needle side portion U1 of the upper thread U is pulled out from the article to be sewn by the wiper mechanism 90, and then the suction nozzle 111A is retracted while performing suction ( It is rotated from the state of FIG. 19 to the vicinity of the position just below the needle hole (state of FIG. 20). Then, with the suction nozzle 111A extending the remaining ends of the upper thread U and the lower thread D downward, the cutting knife 102A of the remaining end cutting mechanism 100A is rotated so that the remaining upper thread U and lower thread D remain. End cutting is performed (state shown in FIG. 21). The remaining ends of the cut upper yarn U and lower yarn D are collected by the suction nozzle 111A.

Thus, the remaining end excision mechanism 100A and the suction mechanism 110A can be used in the same manner as the remaining end excision mechanism 100 and the suction mechanism 110 described above.
Further, although both the above-described thread trimming device 80A and the remaining end cutting mechanism 100A are suitable for a sewing machine using a moving mechanism that does not use a feed dog, the suction mechanism 110A described above is a moving mechanism that uses a feed dog 64. It can be suitably used regardless of whether it is mounted on either a sewing machine equipped with the feed mechanism 60 or a sewing machine using a moving mechanism that does not use a feed dog.

[Other sewing machines]
The above-described sewing machine 10 is an example of a lockstitch sewing machine, but the above-described thread trimming device 80, the remaining end cutting mechanism 100, the suction mechanism 110 or 110A can be applied to other types of sewing machines equipped with a feed mechanism that uses a feed dog. It is possible to apply operation control to these.

Further, for other types of sewing machines equipped with a moving mechanism other than a feed mechanism that uses a feed dog, the above-described thread trimming devices 80 and 80A, the remaining end cutting mechanisms 100 and 100A, the suction mechanisms 110 and 110A, and the above. It is possible to apply motion control.
As another type of sewing machine equipped with a moving mechanism other than a feed mechanism that uses a feed dog, for example, as a moving mechanism for moving a workpiece, sewing can be performed arbitrarily on an XY plane (or R-θ plane). A sewing machine for moving an object (for example, a button-attached sewing machine or an electronic cycle sewing machine described later) is raised.
In the case of a sewing machine equipped with these moving mechanisms, sewing is performed according to the sewing data for forming a constant sewing pattern. Therefore, when the above-described zero pitch control is performed, the sewing end specified in the sewing data is performed. After the needle drop at the position, the needle drop of the final needle is performed at the same position, and then the upper thread U and the lower thread D are cut by the thread trimming device, whereby suitable thread trimming can be performed.
Further, in the case of a sewing machine that arbitrarily moves the workpiece to the XY plane (or R-θ plane), the feed dog descent control is not performed because the feed dog problem does not occur.

[Others]
The thread trimming device is not limited to the one in which the thread trimming knife rotates about the Y axis described above, and for example, a knife mechanism in which the thread trimming knife moves in a horizontal plane can be applied.
Moreover, although the vertical full rotation hook was illustrated as a hook of the hook mechanism 50, not only this but a horizontal hook and a half rotation hook may be utilized. However, in the case of a horizontal hook, it is desirable to use a knife mechanism that moves the thread-cutting knife in a horizontal plane.
The needle plate shown in FIGS. 7 and 8 is semi-elliptical in shape for both the upper plate and the lower plate, but it is sufficient that only the portion where the scalpel for resection is built has a two-layer structure of the upper plate and the lower plate. Both the upper and lower plates do not need to be semi-elliptical.
In the present application, the air cylinder is used as a drive source for adjusting the angle of the feed adjusting body to the condensation pitch and 0 pitch, but a solenoid may be used. Similarly, an air cylinder is used as a driving source for the remaining end excision mechanism and nozzle contact / separation movement, but a solenoid may be used.
Further, although the solenoid is used as a drive source for switching the inclination angle of the feed adjusting body so that the feed direction is changed from the forward direction to the reverse direction, an air cylinder may be used.
The air cylinder 75 for 0 pitch of the feed adjusting mechanism 70 switches the tilt angle of the feed adjusting body so that the feed pitch becomes 0, but it may not be completely 0. For example, the inclination angle of the feed adjusting body may be switched so as to be a minute pitch smaller than the immediately preceding feed pitch (for example, the condensation sewing pitch).

[Second embodiment: Application to sewing machine with buttons]
The remaining end excision mechanism of the present invention can also be applied to a sewing machine (button-attached sewing machine) that sews buttons to a cloth as a sewing object.
Hereinafter, the buttoned sewing machine 10B will be described with reference to FIGS. In addition, about the structure same as the structure already demonstrated, the same code | symbol is attached | subjected and the overlapping description is abbreviate | omitted.

FIG. 23 shows the overall schematic configuration of the button sewing machine 10B, and FIG. 24 shows its control system.
As shown in FIGS. 23 and 24, the button sewing machine 10B includes a sewing machine frame 20, a needle up-and-down moving mechanism 30, a needle plate 40A, a thread trimming device 80A, a wiper mechanism 90, and a remaining end cutting mechanism 100A (FIGS. 17 to 21). A suction mechanism 110A.
The button sewing machine 10B includes a feed mechanism 60B as a moving mechanism for arbitrarily moving the button B and the cloth C along the XY plane with respect to the sewing needle 11, and a hook mechanism 50B as a half-turn hook. The upper thread holding device 130 that holds the sewing start end portion U0 of the upper thread U and the control device 120B that controls each of the entire components are provided.

[Sewing machine with buttons: hook mechanism]
The hook mechanism 50B is a half-turn hook as described above, and transmits a reciprocating rotation operation to the outer hook (not shown), the inner hook 53B including the sword tip 54B (see FIGS. 27B and 29B), and the inner hook 53B. A driver (not shown) is provided. The reciprocating rotation operation of the driver uses the sewing machine motor 31 as a drive source, and a transmission mechanism 52B composed of a cam crank mechanism is provided between the main shaft 32 and a driver shaft 51B that transmits the reciprocating rotation operation to the driver. Yes.
That is, the main shaft 32 makes a full rotation, a connecting rod that rotatably supports an eccentric cam fixed to the main shaft 32 at one end thereof, and a rotation extending outward in the radial direction about the driver shaft 51B. (They are not shown), and the other end of the connecting rod is connected to the rotating end of the rotating arm. As a result, when one end of the connecting rod performs a revolving motion by the eccentric cam, a reciprocating rotational motion is generated in the rotating arm at the other end, and the reciprocating rotational motion is imparted to the driver via the driver shaft 51B. .

[Button sewing machine: Feed mechanism]
As shown in FIGS. 23 and 24, the feed mechanism 60 </ b> B moves the button B and the fabric C along the upper surface of the horizontal needle plate 40 </ b> A to arbitrarily move and position the sewing needle 11.
For this reason, the feed mechanism 60B is supported on the upper surface of the sewing machine bed portion 21 so as to be movable up and down by the lower plate 61B and the base 62B supported so as to be movable along the X-axis direction and the Y-axis direction, and the button 62B. A button knob foot 63B for holding B, a pressing spring 67B for pressing the button knob foot 63B against the upper surface of the lower plate 61B through the base 62B, and a lifting motor 64B for raising the button knob foot 63B against the pressing spring 67B. And an X-axis motor 65B serving as a drive source for moving the lower plate 61B and the base 62B along the X-axis direction, and a drive source for moving the lower plate 61B and the base 62B along the Y-axis direction. Y-axis motor 66B.

The lower plate 61B is a long flat plate provided along the XY plane, and one end thereof is placed on the upper surface of the needle plate 40B.
The base 62B is supported on the rear end side of the upper surface of the lower plate 61B so as to be rotatable around the X axis, and the button knob foot 63B provided on the front end side of the base 62B can be moved up and down by the rotation.
A button knob foot 63B is disposed above the front end of the lower plate 61B. The button knob foot 63B includes a pair of claws for holding the button B, and a holding pressure of the button B is applied by a spring (not shown). That is, the button B can be sandwiched and held by expanding the pair of claws along the X-axis direction against the spring.

As described above, the pressing force is applied to the button knob foot 63B so as to press the upper surface of the lower plate 61B from above by the pressing spring 67B. For this reason, the button knob foot 63B holds the fabric C together with the button B by placing the fabric C on the upper surface of one end of the lower plate 61B.
Further, the button knob foot 63B is lifted by applying upward pressure from the lifting motor 64B through a plurality of link bodies, and can release the holding state of the fabric C.

For example, when the button B is a four-hole button, the X-axis motor 65B and the Y-axis motor 66B have a lower plate 61B and a base 62B so that the four holes are positioned below the sewing needle 11 in a predetermined order. Are sequentially moved in synchronization with the vertical movement of the needle bar 12. The operations of the X-axis motor 65B and the Y-axis motor 66B are controlled by the control device 120B.
Also in the case of sewing with this button, the needle drop is performed at the same position as the last one stitch, and the state where the upper ends of the upper thread U and the lower thread D hang from different positions is avoided. It is possible to improve the sewing quality.

[Button sewing machine: Upper thread holding device]
As shown in FIGS. 25 to 31, the upper thread holding device 130 has a holding state in which the end portion of the upper thread is clamped (held) between the holding surface and the clamping surface, and the upper thread holding device is held (held). Holding means A capable of switching between a released state in which the end is opened, driving means B for switching the holding state and the released state by relatively moving the holding means A, and detection for detecting the operating position of the driving means B And means C.

  The holding means A includes a lower plate 131 as a holding member having a holding surface 1316 and an upper plate 144 as a holding means having a holding surface 1325 disposed to face the holding surface 1316.

As shown in FIG. 25, the lower plate 131 is a substantially flat plate-like member that is long in a certain direction, and the longitudinal direction of the lower plate 131 is parallel to the Y-axis direction while being supported by the driving means B. A rectangular through hole 1312 is formed in the front end portion 1311 of the lower plate 131 along the longitudinal direction of the lower plate 131, and an inner surface that is the most distal side among the four inner peripheral surfaces corresponding to the quadrangle of the through hole 1312. Becomes the holding surface 1316. The holding surface 1316 is parallel to the XZ plane when the lower plate 131 is supported by the driving unit B. Further, a slit-shaped hole 1313 is formed on the rear end side of the lower plate 131 along the longitudinal direction of the lower plate 131. Further, the lower plate 131 is provided with a front pin 1314 that protrudes downward from the lower surface thereof, and a left pin 1315 that protrudes downward slightly to the left rear of the front pin 1314.
The holding surface 1316 functions as a holding surface for sandwiching the upper thread U between the holding surface 1325 and the holding surface 1325.

As shown in FIG. 25, the upper plate 144 includes a tip member 132 having a clamping surface 1325 and an upper plate body 133 that connects and holds the tip member 132 to the front end portion 1331.
The tip member 132 has a sandwiching portion 1322 that extends downward in FIG. 25 on the front end side of the tip member main body 1321, and a protrusion 1323 that projects forward from the lower end of the sandwiching portion 1322 in FIG. A connecting hole 1324 is formed on the rear end side of the member main body 1321. The front surface of the clamping portion 1322 functions as a clamping surface 1325 for clamping the upper thread U between the holding surface 1316 and the holding surface 1316. The clamping surface 1325 is parallel to the XZ plane in a state where the tip member 132 (upper plate 144) is supported by the driving unit B.
The upper plate body 133 is a substantially flat member that is slightly shorter than the lower plate 131. A connecting projection 1332 that protrudes downward is provided at the lower portion of the front end portion 1331 of the upper plate body 133. Further, the upper plate 144 is provided with a rear pin 1333 that protrudes downward from the lower surface thereof, and a right pin 1334 that protrudes downward slightly to the right of the rear pin 1333.
Then, by fitting and connecting the connecting hole 1324 of the tip member 132 and the connecting protrusion 1332 of the upper plate main body 133, the tip member 132 and the upper plate main body 133 are assembled together to form the upper plate 144. .

In the clamping means A, the clamping portion 1322 and the protrusion 1323 of the tip member 132 on the upper plate 144 are inserted into the through hole 1312 of the lower plate 131, and the rear pin 1333 of the upper plate 144 is inserted into the hole 1313 of the lower plate. The upper plate 144 and the lower plate 131 are overlapped so as to be inserted, and the upper plate 144 and the lower plate 131 are relatively movable in the longitudinal direction.
The front pin 1314 of the lower plate 131 and the rear pin 1333 of the upper plate 144 are inserted through a hole portion 1372 of a guide 137 described later, and are connected via a coil spring 139 below the guide 137. .
In the state in which the coil spring 139 is most contracted, the front pin 1314 of the lower plate 131 and the rear pin 1333 of the upper plate 144 are closest to each other, and the left pin 1315 of the lower plate 131 and the right pin 1334 of the upper plate 144 are both The closest. That is, in this state, the left pin 1315 and the right pin 1334 sandwich the lower plate 131 (upper plate 144) and are arranged in a direction perpendicular to the longitudinal direction of the lower plate 131 (upper plate 144).
Further, the coil spring 139 is a tension spring, and always biases the front pin 1314 and the rear pin 1333 in a direction approaching each other, whereby the holding surface 1316 of the lower plate 131 and the clamping surface 1325 of the upper plate 144 are As long as no external force is applied, the contact state is always maintained.

  The drive means B is a drive source for the upper thread holding device 130, and a holding motor 134 as an actuator for switching the state of the holding means A, and a swing link fixedly mounted on a rotating shaft 1341 of the holding motor 134. 140, a connecting member 135 whose one end is connected to the swing end 1402 of the swing link 140 and the other end is connected to the clamping means A via a cam plate link 136 described later, and connected to the cam plate link 136. In addition to holding the holding means A, the guide 137 guides the moving operation thereof, and a guide lid 138 covering the holding means A held by the guide 137.

  The holding motor 134 is a stepping motor that rotates by a predetermined angle in accordance with the operation command signal of the control device 120B, and is driven at a prescribed main shaft angle in accordance with a pulse signal based on the angle of the main shaft 32 output from the encoder 37. .

  The connecting member 135 is arranged along the Y direction in the figure, and a hole 1351 is formed at one end thereof, and a hole 1352 is formed at the other end. The connecting member 135 transmits the displacement in the Y direction at the swing end 1402 of the swing link 140 to the clamping means A via the cam plate link 136.

  The cam plate link 136 is arranged so as to cross the lower plate 131 (upper plate 144), and the longitudinal direction thereof is arranged along the X-axis direction in the drawing. The cam plate link 136 is provided with a cam plate pin 1361 that protrudes downward from the lower surface thereof. Therefore, the cam plate link 136 can swing around the cam plate pin 1361. The cam plate link 136 has a left hole 1362 at one end in the longitudinal direction and a right hole 1363 at the other end. A left pin 1315 of the lower plate 131 and a right pin 1334 of the upper plate 144 are connected to the left hole portion 1362 and the right hole portion 1363, respectively. Further, a cam shape portion 1364 that is slightly curved is provided at the left end portion of the cam plate link 136 so as to correspond to the outer peripheral surface of the roller 142 described later.

The guide 137 is fixed inside the sewing machine bed portion 21.
The guide 137 has a groove portion 1371 having a predetermined width at the center thereof along the front-rear direction, and the groove portion 1371 is formed with an intermediate hole portion 1372 along the front-rear direction. Further, slit-like left hole portions 1373 and right hole portions 1374 are respectively formed along the front-rear direction on both the left and right sides of the groove portion 1371 of the guide 137. Here, the left hole portion 1373 and the right hole portion 1374 are formed in parallel to each other, but the left hole portion 1373 and the right hole portion 1374 are in a slightly shifted positional relationship in the front-rear direction. The left hole 1373 is formed on the front side, and the right hole 1374 is formed on the rear side. A roller 142 is attached to the lower portion of the left edge of the guide 137 with a screw 1375.
The width of the groove portion 1371 is substantially the same as the width of the lower plate 131 and the upper plate 144.

  The guide lid 138 is a substantially flat plate-like member, and is fixed to the guide 137 at two positions on the front side and the rear side by four screws 1381. Thus, the lower plate 131 and the upper plate 144 described above are sandwiched between the guide 137 and the guide lid 138 and guided by the groove portion 1371 of the guide 137 to prevent the lower plate 131 and the upper plate 144 from rattling. To do.

  In the driving means B, a shaft portion 1401 that is one end portion of the swing link 140 is fixed to the rotation shaft 1341 of the holding motor 134. Then, the connecting member 135 is connected to the swing end 1402 of the swing link 140 by a step screw 141 inserted so as to be slidable in a hole 1351 formed at one end of the connecting member 135. . Further, the cam plate link 136 is attached to the hole portion 1352 formed in the other end portion of the connecting member 135 in a state where the cam plate link 136 is pivotally supported by the cam plate pin 1361. With such a configuration, the connecting member 135 moves back and forth along the Y-axis direction by the swing of the swing link 140 accompanying the rotation of the rotation shaft 1341 of the holding motor 134 within a predetermined angle range. The longitudinal movement of the connecting member 135 is transmitted to the cam plate link 136.

Further, a left pin 1315 of the lower plate 131 and a right pin 1334 of the upper plate 144 are inserted into the left hole portion 1373 and the right hole portion 1374 of the guide 137, respectively. The left pin 1315 and the right pin 1334 are The cam plate link 136 is attached by stoppers 143 and 143 so as to be slidable in the left hole portion 1362 and the right hole portion 1363, respectively.
Therefore, the driving force accompanying the rotation of the rotation shaft 1341 of the holding motor 134 is transmitted to the left pin 1315 and the right pin 1334 via the cam plate link 136. Since the left pin 1315 and the right pin 1334 are arranged so as to be movable back and forth by the left hole portion 1373 and the right hole portion 1374, respectively, the driving force thereof is lower plate 131 and upper plate 144 (holding means A). ) Is moved to move back and forth relatively.

  The detection means C includes a first sensor 151 and a second sensor 151 that detect the presence or absence of the slit plate 150 fixed to the connecting member 135 and the slit plate 150 fixed to the inside of the sewing machine bed portion 21 and moving together with the connecting member 135. Sensor 152.

  The slit plate 150 is fixed to the connecting member 135 and is a member that moves back and forth together with the connecting member 135. The slit plate 150 enters and exits a position corresponding to the first sensor 151, and enters and exits a position corresponding to the first detected part 1501 where the presence or absence is detected by the first sensor 151 and the second sensor 152. , And a second detected portion 1502 whose presence or absence is detected by the second sensor 152.

Each of the first sensor 151 and the second sensor 152 includes light emitting elements 1511 and 1521 and light receiving elements 1512 and 1522. For example, an LED is used as the light emitting element and a photosensor is used as the light receiving element. In the following description, it is defined as an off state when the light receiving element receives light emitted from the light emitting element, and an on state when the light receiving element does not receive light emitted from the light emitting element.
Specifically, when the first detected part 1501 blocks the light emitted from the first sensor 151 as the slit plate 150 moves back and forth, the first sensor 151 detects the first detected part 1501 and turns it on. The first sensor 151 is turned off when it is in a state and is not shielded. Then, the first sensor 151 outputs a detection signal indicating whether the sensor is on or off to the control device 120B.
Similarly, when the second detected portion 1502 blocks the light emitted from the second sensor 152, the second sensor 152 detects the second detected portion 1502 and is turned on, and when not blocked, the second sensor 152 is turned on. Is turned off. Then, the second sensor 152 outputs a detection signal indicating whether the sensor is on or off to the control device 120B.
The light path 155 from which the light emitted from the light emitting element travels to the light receiving element is indicated by a dotted line in the plan views of FIGS. 27A, 29A and 30A, and by a dot in the side views of FIGS. 27B, 29B and 30B.
In addition to the position detection by the combination of the light emitting element and the light receiving element, the detection means C may be provided with an encoder in the holding motor 134 and detect the position by detecting the angle of the encoder.

Next, the operation of the upper thread holding device 130 will be described.
First, with reference to FIG. 25, the operation before the start of sewing and immediately after the start of sewing will be described.

  Based on the initial position signal from the control device 120B, the holding motor 134 rotates the rotating shaft 1341 counterclockwise in the drawing at a predetermined angle. As the rotation shaft 1341 rotates, the swing link 140 swings around the shaft portion 1401 (see arrow L0 in FIG. 27A). Further, the connecting member 135 slidably attached to the swing link 140 by the step screw 141 moves (forwards) to the front side as the swing link 140 swings (see arrow M0 in FIG. 27A).

  The cam plate link 136 pivotally supported by the connecting member 135 moves forward as a whole as the connecting member 135 moves forward.

  The right pin 1334 of the upper plate 144 coupled to the right hole portion 1363 of the cam plate link 136 moves forward along the right hole portion 1374 of the guide 137 in accordance with the forward movement of the cam plate link 136, and the right hole portion. The front wall of 1374 collides (abuts), and the forward movement of the right pin 1334 is restricted. At this time, the upper plate 144 integrated with the right pin 1334 also moves forward, and the upper plate 144 is positioned at the foremost position.

  Similarly, the left pin 1315 of the lower plate 131 coupled to the left hole portion 1362 of the cam plate link 136 moves forward along the left hole portion 1373 of the guide 137 as the cam plate link 136 moves forward. At this time, since the left hole portion 1373 and the right hole portion 1374 of the guide 137 are formed relatively forward of the right hole portion 1374, the right pin 1334 of the upper plate 144 is Even after hitting (contacting) the front wall of the right hole portion 1374, the left pin 1315 of the lower plate 131 follows the left hole portion 1373 of the guide 137 so that the right pin 1334 of the upper plate 144 serves as a fulcrum. Move forward. The forward movement of the left pin 1315, that is, the forward movement of the lower plate 131 is continued until the through hole 1312 of the lower plate 131 reaches a predetermined frontmost position directly below the needle hole 431A of the needle plate 40A. When the position is reached, the control device 120B stops when the holding motor 134 is stopped. In addition, the front length of the left hole portion 1373 of the guide 137 is formed to have a margin so that the left pin 1315 does not collide with the front wall of the left hole portion 1373 even after reaching the foremost position. The step-out of the holding motor 134 is prevented.

  When the lower plate 131 and the upper plate 144 are positioned at the foremost position, the front pin 1314 of the lower plate 131 and the rear pin 1333 of the upper plate 144 are separated from each other in the Y-axis direction against the biasing force of the coil spring 139. It becomes. In this case, the front pin 1314 of the lower plate 131 and the rear pin 1333 of the upper plate 144 are urged toward each other in the front-rear direction by the urging force of the coil spring 139, but from the urging force of the coil spring 139. In addition, since the driving force of the holding motor 134 is larger, the lower plate 131 can be positioned at the foremost position against the urging force of the coil spring 139.

Further, when the lower plate 131 and the upper plate 144 are positioned at the foremost position, the holding surface 1316 in the through hole 1312 of the lower plate 131 and the clamping surface 1325 and the protrusion of the tip member 132 attached to the front end portion 1331 of the upper plate 144 The front end of the portion 1323 is separated in the Y-axis direction, and the through hole 1312 is open. At this time, the through hole 1312 and the needle hole 431A of the needle plate 40A overlap each other, and the sewing needle 11 of the first stitch after the start of sewing is in the through hole 1312 and the needle hole 431A of the needle plate 40A. It will be possible to move up and down through. In this way, the position where the clamping means A is positioned on the vertical movement path of the sewing needle 11 is referred to as “initial position” in the following description. In this initial position, the clamping means A is in a “released state” in which the upper thread is not held or clamped.
In this “initial position”, the slit plate 150 of the detecting means C is moved forward with the forward movement of the connecting member 135, and the first detected portion 1501 and the second detected portion 1502 of the slit plate 150 are The first sensor 151 and the second sensor 152 are in non-detection positions, respectively, and are in the off state.

  When the clamping means A is positioned at the “initial position”, the sewing needle 11 of the first stitch through which the end U0 on the sewing start side of the upper thread U is inserted passes through the needle hole 431A and the through hole 1312. Move up and down. The end U0 of the upper thread U is pulled downward by the sword tip 54B of the inner hook 53B of the hook mechanism 50B when the sewing needle 11 is lowered, and thereafter when the sewing needle 11 is raised, as shown in FIG. In addition, a state in which the end portion U0 of the upper thread U is inserted into the through hole 1312 hangs down.

  Next, with reference to FIGS. 29A and 29B, the operation of the upper thread holding device 130 after the start of sewing (after the first stitch sewing needle 11 moves up and down) will be described.

  Based on the intermediate holding position signal from the control device 120B, the holding motor 134 rotates the rotating shaft 1341 clockwise at a predetermined angle in the drawing. As the rotation shaft 1341 rotates, the swing link 140 swings around the shaft portion 1401 (see arrow L1 in FIG. 29A). Further, the connecting member 135 slidably fixed to the swing link 140 by the step screw 141 moves rearward (backward movement) as the swing link 140 swings (see arrow M1 in FIG. 29A). ).

  The cam plate link 136 that is pivotally supported by the connecting member 135 moves rearward as a whole as the connecting member 135 moves rearward.

  When the cam plate link 136 starts moving backward, first, the rear pin 1333 of the upper plate 144 is pulled in the direction of the front pin 1314 of the lower plate 131 by the biasing force of the coil spring 139. With the pin 1334 still in contact with the front wall of the right hole 1374 of the guide 137, only the lower plate 131 starts to move backward. When the lower plate 131 is moved by a predetermined amount and stopped, the holding surface 1316 of the lower plate 131 is positioned behind the tip of the protrusion 1323 of the upper plate 144, and the through hole 1312 is closed. "

This “intermediate holding position” is a state in which only the lower plate 131 is moving backward, the cam plate pin 1361 of the cam plate link 136, the right pin 1334 of the upper plate 144, and the left pin of the lower plate 131. 1315 is an arrangement until the arrangement is made in a row in a direction substantially perpendicular to the longitudinal direction of the clamping means A (the lower plate 131 and the upper plate 144). During this time, the holding motor 134 rotates at a predetermined angle corresponding to the “intermediate holding position”.
In this “intermediate holding position”, the slit plate 150 of the detecting means C is moved rearward with the rearward movement of the connecting member 135, and the first sensor 151 detects the first detected portion 1501 of the slit plate 150. In position and on. In addition, the second detected portion 1502 is in the non-detection position in the second sensor 152 and is in the off state.

The movement of the lower plate 131 from the “initial position” to the “intermediate holding position” is completed by the time the lift of the balance is started. In this “intermediate holding position”, the upper surface 131 and the holding surface 1316 of the lower plate 131 are moved upward. It is not in contact with the clamping surface 1325 of the plate 144, and the upper thread is not clamped or held. In this state, the upper thread U that the balance pulls upward is bent, and resistance to lifting of the upper thread U is given.
By giving such resistance, it is possible to prevent the upper thread U that is pulled up by the balance from sagging due to the inertial force and to prevent the needle thread U from coming off from the clamping means A. The length from the hole to the end portion U0 of the sewing start of the upper thread U can be kept constant.

  Next, with reference to FIG. 309A and FIG. 30B, the operation of the upper and lower thread holding device 130 before and after the holding means A clamps and holds the upper thread U after the “intermediate holding position” will be described.

  The holding motor 134 rotates clockwise from the above-mentioned “intermediate holding position” to swing the swing link 140, and the cam is moved by the rearward movement of the connecting member 135 accompanying the swing of the swing link 140. The plate pin 1361, the right pin 1334, and the left pin 1315 are arranged in a row in a direction perpendicular to the longitudinal direction of the clamping means A. In this state, the front pin 1314 of the lower plate 131 and the rear pin 1333 of the upper plate 144 are biased by the biasing force of the coil spring 139 so as to be closest to each other in the front-rear direction. Along with this, the holding surface 1316 of the lower plate 131 and the clamping surface 1325 of the upper plate 144 abut (actually, the upper thread U is interposed, so that the state is close to abutment without complete contact), and FIG. As shown, the clamping means A is the “upper thread clamping position” where the upper thread U is clamped. At the upper thread clamping position, the clamping means A is in the “clamping state”.

  After reaching the “upper thread clamping position”, the holding motor 134 continues to rotate the rotation shaft 1341 clockwise at a predetermined angle in the drawing based on the retracted position signal from the control device 120B. As the rotation shaft 1341 rotates, the swing link 140 swings about the shaft portion 1401 (see arrow L2 in FIG. 30A). Further, the connecting member 135 slidably fixed to the swing link 140 by the step screw 141 moves rearward (rearward movement) as the swing link 140 swings (see arrow M2 in FIG. 30A). ).

  The cam plate link 136 that is pivotally supported by the connecting member 135 moves rearward as a whole as the connecting member 135 moves rearward.

  In this state, since the clamping surface 1325 and the holding surface 1316 are in contact with each other, the upper plate 144 and the lower plate 131 that are biased by the coil spring 139 are not moved any more in the mutual proximity direction. Accordingly, the rear movement of the cam plate link 136 causes the lower plate 131 and the upper plate 144 to move backward by the same amount. That is, the clamping means A enters the clamping state and moves backward while clamping the upper thread U.

In this way, the clamping means A moves to the “retraction position” that has moved slightly after the “upper thread clamping position” while maintaining the clamping state of the upper thread U. This “retracted position” is the rear side of the needle hole 431A of the needle plate 40A, and the end U0 of the upper thread U passing from the needle hole 431A to the clamping means A is reciprocated when the thread trimmer 80A performs thread trimming. The position is such that it does not come into contact with the thread cutting knife 81A that performs the moving operation.
At this “retracted position”, the slit plate 150 of the detecting means C is moved rearward with the rearward movement of the connecting member 135, and the first detected portion 1501 and the second detected portion 1502 of the slit plate 150 are The first sensor 151 and the second sensor 152 are at detection positions, respectively, and both are in the on state.
Then, in a state where the clamping means A is retracted to this “retracted position”, the sewing is performed up to the final needle.

  In this way, the upper thread holding device 130 switches the position of the clamping means A between the initial position and the standby position, thereby switching between the clamped state and the released state of the upper end U0 of the upper thread U. Can be done.

[Button sewing machine: Operation control]
As shown in FIG. 24, the control device 120B has the same hardware configuration as the control device 120 described above, and includes a CPU 121, a ROM 122, a RAM 123, and an EEPROM 124.
The control device 120B includes a sewing machine motor 31 and an encoder 37 of the needle up-and-down moving mechanism 30, an X-axis motor 65B, a Y-axis motor 66B, a lifting motor 64B, a feed mechanism 60B, via a system bus and a drive circuit. A thread trimming motor 86A for rotating the thread trimming knife 81A of the thread trimming device 80A, a thread trimming air cylinder 103A for the remaining end trimming mechanism 100A, a wiper solenoid 92 for the wiper mechanism 90, and a suction magnet for the suction mechanism 110A. The valve 114A, the nozzle moving air cylinder 113A, the holding motor 134 of the upper thread holding device 130, the first sensor 151, the second sensor 152, and the like are connected.
The yarn cutting air cylinder 103A and the nozzle moving air cylinder 113A are actually controlled by the control device 120B with respect to the electromagnetic valves that operate them, but the illustration of each electromagnetic valve is omitted here.

Further, similarly to the control device 120, an operation input unit 125 is connected to the control device 120B.
The operation input unit 125 sets, for example, the number of button holes to be sewn, the size of each hole, the order of needle movement to each hole, and the number of needles.
Further, since the button sewing machine 10B performs button sewing with a predetermined number of stitches set in advance, it does not include the pedal 126 for inputting a thread trimming execution command. Instead, a sewing execution command is issued. A start pedal 126B for inputting is provided.

[Button sewing machine: Sewing operation]
Next, the button sewing operation of the buttoned sewing machine 100B will be described with reference to the flowchart of FIG. 32 and the operation explanatory diagrams of FIGS.
First, when the cloth C, which is a sewing object, is placed on the upper surface of the lower plate 61B, the button B is set on the button knob foot 63B, and the start pedal 126B is pressed, the control device 120B moves the feed mechanism 60B up and down. The motor 64B is controlled to lower the button knob foot 63B onto the fabric C. As a result, the button B and the fabric C are held by the button knob foot 63B (step S101).

  Next, the control device 120B controls the holding motor 134 to move the pinching means A of the upper thread holding device 130 to the initial position. As a result, the holding surface 1316 and the clamping surface 1325 of the clamping means A are opened below the needle hole 431A (step S103, FIG. 33, released state).

  Next, the control device 120B starts driving the sewing machine motor 31 (step S105). Thereby, the needle drop of the first stitch is performed between the holding surface 1316 and the clamping surface 1325 of the clamping means A. The control device 120B monitors the output of the encoder 37, and operates the holding motor 134 at a predetermined spindle angle at which the sewing needle 11 moves upward and comes out from between the holding surface 1316 and the holding surface 1325 of the holding means A. Then, the clamping means A is moved to the intermediate holding position (step S107). As a result, the clamping means A moves to the standby position side, and the holding surface 1316 and the clamping surface 1325 are brought into the proximity state. For this reason, when the upper thread U is pulled up by the balance, a predetermined resistance force of the upper thread U can be applied, and the slack of the upper thread U is suppressed.

Further, the control device 120B monitors the output of the encoder 37, and when the balance passes through its top dead center, it operates the holding motor 134 and moves the holding means A to the standby position (step S109, holding state). .
As a result, the clamping means A is separated from the needle hole 431A, the holding surface 1316 and the clamping surface 1325 are in the closest state, and the end portion U0 of the upper thread U at the start of sewing is clamped.
Thereafter, the needle drop is performed in the prescribed order with respect to the button hole with the set number of stitches of button sewing (step S111).

Then, when the sewing needle 11 is raised after the last needle drop, the control device 120B operates the thread trimming motor 86A to start thread trimming by the thread trimming apparatus 80A (step S113).
That is, only the portion of the thread trimming moving knife 81A of the thread trimming device 80A connected to the side of the sewing needle 11 in the loop of the upper thread U formed by the inner hook 53B below the fabric C in the reciprocating rotation path. 34 (FIG. 34), and in the return path of reciprocating rotation, the portion connected to the fabric C side in the loop of the upper thread U and the lower thread D extending from the inner hook 53B to the fabric C side are fixed to the thread cutting fixing knife 82A side. To cut (FIG. 35).
At this time, since the end U0 of the upper thread sewing start is in a state where the clamping means A is pulled to the standby position side and retracted, it is outside the rotation range of the thread cutting knife 81A and is not cut.

  When the sewing machine motor 31 stops at a predetermined upper stop position (step S115), the control device 120B controls the wiper solenoid 92 to execute yarn wiper with the wiper (step S117). Thereby, the portion on the sewing needle 11 side of the upper thread U cut by the thread trimming device 80A is pulled out above the button B (FIG. 36).

  Then, the control device 120B operates the yarn cutting air cylinder 103A so that the upper ends of the upper yarn U and the lower yarn D after the cutting of the yarn trimming device 80A remaining on the lower side of the fabric C, and the fabric C The end portion U0 of the upper thread U across the clamping means A at the start of sewing is cut off at a position near the lower surface of the fabric C (step S119).

Next, the control device 120B operates the holding motor 134 to move the clamping means A to the initial position (step S121). As a result, the clamping means A is released, and the sewing start end U0 of the cut upper thread U is released from the clamping state between the holding surface 1316 and the clamping surface 1325 (FIG. 37).
Further, the control device 120B operates the nozzle moving air cylinder 113A and the suction electromagnetic valve 114A to move the tip of the suction nozzle 111A below the needle hole 431A and perform suction, and cut the upper thread U cut out. Then, the remaining end of the lower thread D and the end U0 of the upper thread U at the start of sewing are sucked (step S123).
Then, the control device 120B controls the raising / lowering motor 64B of the feed mechanism 60B to raise the button knob foot 63B (step S125). As a result, the fabric C is released from the button knob foot 63B, and the sewing is completed.

As described above, in the button sewing machine 10B, since the upper end U0 of the upper thread U is held in the standby position by the clamping means A until the final needle by the upper thread holding device 130, the upper thread in the sewing process. It is possible to effectively suppress the U-start end U0 of the U from being entangled with the upper thread U and the lower thread D to form a so-called bird's nest state.
Further, since the end portion U0 of the held upper thread U at the start of sewing is finally cut by the remaining end cutting mechanism 100A, the remaining end of the upper end U0 of the upper thread U in the fabric C is made shorter. Therefore, it is possible to realize good button sewing with a good appearance.

[Other examples of the shape around the needle hole]
As described above, the needle plate guide 44A is provided in the lower plate 42A, which is the lower layer of the needle plate 40A.
A needle hole 441A penetrating vertically is formed at the center of the needle hole guide 44A. The needle hole 441A is concentric with the needle hole 431A of the needle hole forming plate 43A and has the same inner diameter. Yes.
As shown in FIGS. 38, 39A, and 39B, the peripheral portion of the needle hole 441A on the upper surface of the needle hole guide 44A is made higher than the other portions on the upper surface of the needle hole guide 44A to form a boss-like protrusion 443A. It is desirable. The boss-like protrusion 443A is circular in plan view and is formed to be concentric with the needle hole 441A. Further, a chamfer 442A may be formed at the upper end of the needle hole 441A.

  In the lower side of the needle hole guide 44A, thread processing such as threading and thread trimming for selectively selecting the upper thread U and the lower thread D is performed. By forming the needle hole 441A in the needle hole guide 44A, these needle holes 441A are formed. During yarn processing, each yarn can be guided to an appropriate position and held at an appropriate position.

Further, since the remaining ends of the upper thread U and the lower thread D cut by the remaining end cutting mechanism 100A are sucked by the suction nozzle through the needle hole 441A below the needle hole guide 44A, the boss-shaped protrusion 443A is formed. By providing, the upper end portion of the needle hole 441A can be brought closer to the remaining end excision mechanism 100A, and the remaining end can be sucked more satisfactorily.
Further, since the boss-like protrusion 443A is higher than the other portions on the upper surface of the needle hole guide 44A, the generation of airflow toward the needle hole 441A along the upper surface of the needle hole guide 44A during suction is reduced, Suction can be performed more effectively from top to bottom.

  Although the needle plate 40A is illustrated here, a boss-like protrusion may be formed around the upper end of the needle hole 421 of the lower plate 42 in the case of the needle plate 40 as well.

[Relationship between remaining end processing mechanism and needle hole]
For example, the remaining end excision mechanism 100A described above includes the excision fixing knife 101A on the upper side and the excision moving knife 102A on the lower side between the upper plate 41A serving as the upper layer of the needle plate 40A and the lower plate 42A serving as the lower layer. ing. The reason why the excision fixing knife 101A is arranged on the upper side is to secure the strength of the upper plate 41A. That is, since the upper plate 41A is required to be thinner in order to make the remaining end shorter, the upper plate 41A is fixed in a state where the cutting knife 101A is fitted in the recess formed on the lower surface thereof. If the excision moving knife 102A is arranged on the upper side, the concave portion formed on the lower surface of the upper thread becomes wide in consideration of the operating range of the knife, and the strength decreases. Therefore, the strength of the needle plate 40A can be ensured by disposing the cutting knife 101A on the upper side.

As shown in FIG. 39A, through holes 101Ab and 102Ab into which the upper thread U and the lower thread D are inserted are formed in both the resecting fixed knife 101A and the resecting moving knife 102A. Then, the cutting knife 102A moves in the Y-axis direction to cut the upper thread U and the lower thread D.
Further, the through holes 101Ab and 102Ab of the excision fixing knife 101A and the excision moving knife 102A are both circular openings on the surfaces facing each other, and have the smallest dimension (minimum diameter) on the surfaces facing each other. ing.
Furthermore, these circular openings on the surfaces facing each other are in a state where the excision moving knife 102A is in the standby position during the non-excision operation, and both of them are located on the needle hole 431A on the upper plate 41A side and the lower plate 42A side. It is concentric with the needle hole 441A, and its inner diameter d2 coincides with the inner diameter d1 of the needle hole 431A and the needle hole 441A.

FIG. 39A shows a state in which the excision moving knife 102A is in the standby position during the non-excision operation, and FIG. 30B shows a state in which the excision moving knife 102A has moved in the excision operation direction.
When the cutting knife 102A moves in the cutting operation direction, the region s shown in FIG. 30B becomes a pocket into which the remaining end of the cut upper thread U or lower thread D may enter. In this region s, the remaining end of the upper thread U or the lower thread D becomes harder to enter as the width of the cutting knife 102A in the cutting operation direction becomes shallower. The region s is formed on the side opposite to the cutting edge of the cutting knife 102A for cutting, and the depth of the region s matches the minimum width d2 of the through hole 102Ab in the cutting operation direction.
On the other hand, unless the minimum width d2 of the through hole 102Ab of the cutting knife 102A in the cutting operation direction is at least equal to or greater than the width d1 of the needle holes 431A and 441A, the upper thread U, the lower thread D, and the sewing needle 11 can be inserted smoothly. It becomes impossible to do. Therefore, the minimum width d2 in the cutting operation direction of the through hole 102Ab of the cutting knife 102A for cutting is easy to insert the upper thread U, the lower thread D, and the sewing needle 11, and the remaining ends of the upper thread U or the lower thread D are less. In order to satisfy both requirements that it is difficult to enter, the width d1 of the needle holes 431A and 441A is made coincident.

Thereby, it is possible to satisfactorily suck the remaining ends of the upper thread U or the lower thread D while ensuring the insertion of the upper thread U, the lower thread D and the sewing needle 11.
Although the remaining end excision mechanism 100A is illustrated here, the remaining end excision mechanism 100 also has a circular shape in the elongated hole 102b of the excision moving knife 102, and the minimum width in the excision operation direction (the opening of the fixed knife side). The width in the excision operation direction) may be the same as the width of the needle holes 411 and 421 in the same direction.

[Center press]
The above-mentioned button sewing machine 10B may be provided with an intermediate presser 621B for preventing the cloth C from being pulled toward the button B side between the button B held at the time of sewing and the cloth C as the sewing object. .
As shown in FIG. 40, the intermediate presser 621B is a bar-like member that is provided at the front end in the Y-axis direction of the base 62B of the feed mechanism 60B and extends toward the front end along the Y-axis direction.
The height of the intermediate presser 621B is set so as to be between the fabric C held from above by the pair of button knob feet 63B and the button B sandwiched by the pair of button knob feet 63B. Further, the arrangement in the X-axis direction is set so as to pass through the middle of the button B held between the pair of button knob feet 63B.

Thereby, when the button B has two holes or four holes, as shown in FIG. 41A, the intermediate presser 621B can be placed between the button holes.
Therefore, when performing sewing to sew the button B to the cloth C, the cloth C can be pressed between the button holes from above. As a result, as shown in FIG. 41B, it is possible to suppress the fabric C from being pulled upward by pulling the sewing needle 11 or pulling the upper thread U between the button holes.
When the cloth presser 421B suppresses the pulling up of the cloth C between the button holes, the gap between the cloth C and the upper surface of the needle plate 40A can be reduced. Thereby, after cutting off the remaining ends of the upper thread U and the lower thread D, the remaining ends can be shortened by the gap.

  The sewing machine according to the present invention can be used with respect to a sewing machine in which a remaining end of a sewing thread can occur on a sewing product after automatic thread trimming.

10 sewing machine 11 sewing needle 12 needle bar 20 sewing machine frame 30 needle vertical movement mechanism 31 sewing machine motor 32 spindle 37 encoder 40, 40A needle plate 41, 41A upper plate (upper needle plate)
42,42A Lower plate (lower needle plate)
50, 50B Hook mechanism 60, 60B Feed mechanism (moving mechanism)
64 Feed dog 70 Feed adjustment mechanism 74 Condensation air cylinder 75 0 pitch air cylinder 76 Reverse feed solenoid 80, 80A Thread trimmer 81, 81A Thread trimmer moving knife 82, 82A Thread trimmer stationary knife 90 Wiper mechanism 91 Wiper 100,100A Remaining end cutting mechanism (thread cutting mechanism)
101,101A Fixed scalpel for excision (scalpel for excision)
101Ab through hole 102, 102A moving knife for cutting (cutting knife)
102Ab Through-hole 103, 103A Yarn cutting air cylinder 110, 110A Suction mechanism 111, 111A Suction nozzle 113, 113A Nozzle moving air cylinder (nozzle driving means)
114 Electromagnetic valve for suction 120 Control device (suction control device)
126 Pedal (signal input means)
130 Upper thread holding device 134 Holding motor (actuator)
411, 421, 431A Needle hole 443A Boss-like projections 412, 422 Retraction hole 621B Intermediate presser D Lower thread U Upper thread U1 Needle side portion U2 of upper thread loop Sewing side portion of upper thread loop

Claims (11)

A needle plate in which a needle hole into which a sewing needle is inserted is formed;
A moving mechanism for moving the workpiece along the upper surface of the needle plate;
A needle up-and-down movement mechanism for moving up and down the sewing needle;
A hook mechanism that captures the upper thread from the sewing needle below the needle plate and entangles the lower thread,
A thread trimming device provided between the needle plate and the shuttle mechanism for cutting the lower thread and the upper thread;
A wiper mechanism for pulling out a sewing needle side portion of the upper thread cut by the thread trimming device to the upper side of the sewing product;
In a sewing machine comprising the moving mechanism, the thread trimming device, and a control device that controls the operation of the wiper mechanism,
A remaining end excision mechanism disposed below the upper surface of the needle plate and above the thread trimming device,
After cutting the lower thread and the upper thread by the thread trimming device,
The remaining ends of the lower thread and the upper thread connected to the sewing product are cut out by the remaining end cutting mechanism ,
The needle plate has an upper and lower two-layer structure,
The remaining end excision mechanism is built between upper and lower layers of the needle plate, and has a cutting knife for excising the lower end of the lower thread and the upper thread connected to the sewing product after cutting by the thread trimming device,
Concentric needle holes are formed in both the upper needle plate and the lower needle plate,
The remaining end excision mechanism includes a fixed knife on the upper side and a moving knife on the lower side as the knife for cutting between the upper needle plate and the lower needle plate . The control device is configured to reduce the feed amount from the needle drop position immediately before the needle drop position of the final needle for performing thread trimming by the thread trimming device to 0 or less than the feed amount immediately before the needle drop position. The sewing machine according to claim 1 , wherein the feed amount is controlled. The moving mechanism feeds the sewing object with a feed dog that protrudes and retracts from the retracting hole of the needle plate,
The controller, after cutting the lower thread and the upper thread by the thread trimming device, reduces the amount of protrusion of the feed dog from the needle plate by rotating a sewing machine motor , and then the remaining of the lower thread and the upper thread. 3. The sewing machine according to claim 1 , wherein the remaining end excision mechanism is controlled so as to perform end excision. Wherein the control device, the input of the yarn switching signal by the signal input means is detected, claims and controlling the feeding amount of the moving mechanism so that the predetermined condensed stitch pitch a predetermined number of stitches Item 4. The sewing machine according to any one of Items 1 to 3 . The sewing machine is a button-attached sewing machine that sews buttons to a sewing product,
An upper thread holding device that is disposed below the needle plate and the remaining end excision mechanism and above the shuttle mechanism, and holds an upper end of sewing of the upper thread;
The upper thread holding device includes: a clamping unit capable of switching between a released state of an end part at the start of sewing of the upper thread and a clamped state of an end part of the sewing start of the upper thread; and the clamping unit from the released state. And an actuator for switching to the clamping state,
The control device includes:
Switching the holding means from the released state to the holding state after the needle drop of the first needle of the button sewing,
Perform thread trimming by the thread trimming device after the needle drop of the last needle of the button sewing,
3. The sewing machine according to claim 1 , wherein after the thread trimming is performed by the thread trimming device, control to switch the clamping unit to the released state is performed. The sewing machine according to any one of claims 1 to 5 , further comprising a suction mechanism that performs suction from below a needle hole of the needle plate. The sewing machine according to claim 6 , wherein the suction mechanism includes a suction nozzle that can move toward and away from a needle hole of the needle plate, and a nozzle driving unit that applies the contact and separation movement operation. 8. The suction control device according to claim 7 , further comprising a suction control device that controls the suction mechanism to start suction at the same time as or before the suction nozzle that performs the movement arrives at a needle hole of the needle plate. sewing machine. The sewing machine according to any one of claims 1 to 8, wherein a peripheral portion of the needle hole on the upper surface of the lower needle plate is formed higher than other portions of the upper surface of the lower needle plate. . Each of the fixed knife and the moving knife has a through-hole through which the upper thread and the lower thread are inserted,
Any one of claims 1 to 9, characterized in that the minimum width in the excision operation direction of the moving knife of the through hole of the moving knife matches the width of the cutting operation direction of the needle hole of the upper needle plate The sewing machine according to Item . The sewing machine according to claim 5 , further comprising an intermediate presser for preventing the sewing product from being pulled toward the button side between the button held during sewing and the sewing product.

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