JP2009005933A - Buttonhole sewing machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To form a buttonhole by cutting cloth with proper cutting force in accordance with cutting length of the buttonhole so as to reduce wearing and deterioration of a buttonhole cutting mechanism. <P>SOLUTION: The electronic eyelet buttonhole sewing machine 1 is provided with the buttonhole cutting mechanism 14 to form a buttonhole on the cloth W by cutting it, a buttonhole cutting mechanism drive means 18 to drive the buttonhole cutting mechanism 14, and a control means to control the buttonhole cutting mechanism drive means 18 for varying the cutting force of the buttonhole cutting mechanism 14. The control means controls the buttonhole cutting mechanism drive means in such a way that the cutting force is stronger when the cutting length of the buttonhole is longer than when shorter. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a hole sewing machine having a button hole cutting mechanism.

  2. Description of the Related Art Conventionally, in an eyelet stitching machine, buttonholes such as eyelet holes and eyelet sleep holes are cut and formed on a work cloth, and then eyelet stitching or stitching is performed (for example, Patent Document 1).

In this configuration, a fixed blade fixed to the sewing machine frame via a fixed blade base, an arm member pivotally supported by the sewing machine frame, a hammer fixed to the tip of the arm member, An air cylinder for driving the hammer, and the air cylinder is actuated to move the hammer down through the arm member by the operation of the piston rod, and the work cloth placed on the feed base is placed on the work cloth. The button hole is cut and formed by the cooperation of the fixed blade.
JP 2000-210488 A

  In the above configuration, the button hole cutting length is variously changed. However, when the hammer operating force (pressing force against the fixed blade) is constant, the eyelet hole cutting length is short. However, although the torque required for cutting may be small, the operation force of the hammer is relatively large, and the hammer and the fixed blade are consumed quickly.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to cut and form the button hole with a cutting force corresponding to the cutting length of the button hole, thereby reducing wear and deterioration of the button hole cutting mechanism. The object is to provide a hole sewing machine.

In order to change the cutting force of the button hole cutting mechanism, the button hole cutting mechanism for cutting and forming the button hole in the work cloth, the button hole cutting mechanism driving means for driving the button hole cutting mechanism, and the button hole cutting mechanism Control means for controlling the button hole cutting mechanism driving means, and the control means drives the button hole cutting mechanism so that the cutting force is stronger when the button hole cutting length is longer than when the button hole cutting length is short. It is characterized in that it controls the means.
If the cutting force is set to be uniquely strong, the cutting load is large and the cutting force is moderate when the cutting length is long, but the cutting load is small when the cutting length is short. Therefore, the cutting force of the button hole cutting mechanism is excessively large.

  In the first aspect of the invention, the cutting force of the button hole cutting mechanism can be changed by the control means controlling the button hole cutting mechanism driving means. Since this control means controls the button hole cutting mechanism driving means so as to increase the cutting force when the button hole cutting length is shorter than when the button hole cutting length is short, when the button hole cutting length is long, The cutting force can be strengthened so that there is no shortage of cutting, and when the button hole is short, excessive cutting force can be eliminated, and the consumption and deterioration of the button hole cutting mechanism can be reduced without causing shortage of cutting. .

According to a second aspect of the present invention, in the first aspect of the invention, there is provided detection means for detecting completion of cutting by the button hole cutting mechanism, and the control means detects the button hole cutting when the detection means detects completion of cutting. It is characterized in that it is controlled to stop the cutting operation of the mechanism.
In the invention of claim 2, since the cutting operation of the button hole cutting mechanism is stopped when the completion of cutting is detected by the detecting means, the button hole cutting mechanism does not prolong the cutting operation of the button hole cutting mechanism. Wear and deterioration can be reduced, and for example, it is possible to quickly shift to the next sewing operation.

According to a third aspect of the present invention, in the first or second aspect of the invention, the buttonhole cutting mechanism is constituted by a fixed blade and a movable hammer, and the buttonhole cutting mechanism driving means is a driving mechanism for driving the hammer. The cutting length is configured in accordance with the type of the fixed blade and the contact length of the hammer with respect to the fixed blade.
In the invention of claim 3, since the cutting length can be determined by knowing the type of the fixed blade and the contact length of the hammer with the fixed blade, the type of the fixed blade and the contact of the hammer with the fixed blade The cutting force can be easily changed according to the length.

According to a fourth aspect of the present invention, in the first or second aspect of the invention, the buttonhole cutting mechanism includes a fixed blade and a movable hammer, and the buttonhole cutting mechanism driving means is a drive mechanism that drives the hammer. When the contact length of the hammer with respect to the fixed blade is a fixed length, the cut length of the button hole is set according to the type of the fixed blade.
In the invention of claim 4, since the length of the blade portion of the fixed blade is known in its type, if the type of the fixed blade is known, the cutting length is also known. The cutting force can be easily changed when the length is constant.

According to a fifth aspect of the present invention, in the first or second aspect of the invention, the buttonhole cutting mechanism includes a fixed blade and a movable hammer, and the buttonhole cutting mechanism driving means is a drive mechanism that drives the hammer. In the case where the fixed blade has a fixed length, the cutting length of the button hole is determined according to the contact length of the hammer with respect to the fixed blade.
In this invention of claim 5, if the contact length of the hammer with respect to the fixed blade is known, the cutting length can also be determined according to the corresponding contact length. Therefore, the cutting force is changed when the fixed blade has a constant length. Is easy.

The invention of claim 6 is characterized in that, in the invention of any one of claims 1 to 5, the cutting length is constituted by the length of the eyelet part and the leg part.
In the invention of claim 6, when the button hole is an eyelet hole, the cutting length becomes an appropriate length considering the eyelet hole, and an appropriate cutting force can be set.
The invention of claim 7 is characterized in that, in the invention of any one of claims 2 to 6, the detection means is constituted by a detector for detecting the height of the hammer.
In the invention of claim 7, the completion of cutting can be detected with a simple configuration.

  According to the present invention, even when the cutting length of the button hole is changed, the optimum cutting force can be obtained according to the cutting length, and the wear and deterioration of the button hole cutting mechanism can be reduced.

Hereinafter, a first embodiment in which the present invention is applied to an electronic eyelet sewing machine will be described with reference to FIGS.
As shown in FIG. 1, an electronic eyelet perforated sewing machine 1 that is a perforated sewing machine includes a fixed blade 5 that is detachably fixed to a frame 2 a of a bed portion 2 via a fixed blade base 15, and an arm portion. 3 has a cutter shaft member 7 supported by a frame 3a through a direct acting support mechanism 6 so as to be movable up and down, and is detachably fixed to the lower end of the cutter shaft member 7 and has a fixed blade receiving surface 8c at the lower end. A hammer 8, a hammer driving air cylinder 9 for driving the hammer 8, a transmission mechanism 10 for transmitting the driving force of the hammer driving air cylinder 9 to the hammer 8, and a presser drive for driving the presser foot 65 A mechanism 60 and the like are provided.

  The fixed blade 5 and the hammer 8 constitute a button hole cutting mechanism 14. The support mechanism 6, the hammer driving air cylinder 9, the transmission mechanism 10, and the air pressure regulator 100 shown in FIG. 9 constitute a button hole cutting mechanism driving means 18, and this button hole cutting mechanism. The drive means 18 is constituted by a drive mechanism that drives the hammer 8.

In the arm portion 3 of the electronic eyelet stitching sewing machine 1, although not shown, a needle bar vertical swing drive mechanism that swings left and right while moving a needle bar having a sewing needle at the lower end up and down, and swings the needle bar. Various mechanisms necessary for sewing are provided, such as a needle bar turning mechanism.
As shown in FIG. 1, a feed base 16 on which the work cloth W is placed is provided on the upper surface portion of the bed portion 2. The feed base 16 has a thin rectangular box shape as a whole, and a portion facing the fixed blade 5 is opened by a notch.

  In the bed portion 2, an X-direction drive motor 96 (see FIG. 9) and an X-direction drive mechanism for moving the feed table 16 in the X direction (left and right direction), and a Y direction drive for moving in the Y direction (front and rear direction). A motor 98 (see FIG. 9) and a Y-direction drive mechanism are provided. The fixed blade base 15 is placed and fixed on the frame 2 a of the bed portion 2, and the fixed blade 5 is fixed to the fixed blade base 15 so that the upper end thereof is substantially at the same height as the upper surface of the feed base 16. .

As shown in FIG. 10, the blade shape of the fixed blade 5 is composed of an eyelet portion 5a and a leg portion 5b.
The hammer 8 has a flat surface on the fixed blade 5 side.
Next, the linear motion type support mechanism 6 that supports the cutter shaft member 7 having the hammer 8 attached to the lower end so as to be movable up and down will be described with reference to FIGS. 1 and 3 to 5.
A circular mounting hole 23b is formed in the horizontal frame 3a on the lower side of the arm portion 3, and a substantially cylindrical shape having a substantially annular mounting collar portion 20a on the lower side so as to be fitted into the mounting hole 32b from the lower side. The holder member 20 is disposed, and is fixed from below by a plurality of fixing bolts 21. A cylindrical hammer support 22 is fitted into the holder member 20 from below.

  As shown in FIG. 6, chamfered portions 22a having a predetermined width are formed in substantially upper half portions on both the left and right sides of the hammer support body 22, respectively. A pivotal support wall portion 20b is formed on each of the left and right sides of the holder member 20 corresponding to the chamfered portions 22a, and each chamfered portion 22a comes into contact with the corresponding pivoted projection wall portion 20b from the inside, so that the hammer The support 22 is prevented from rotating. The inner diameter of the holder member 20 is slightly larger than the outer shape of the hammer support 22.

  As shown in FIG. 6, the hammer support 22 is formed with small-diameter pin holes 22b facing each other on the lower side of the chamfered portion 22a, and the pivot support wall portion 20b has the small-diameter pin holes 22b. A large-diameter pin hole 20c having an inner diameter larger than the diameter is formed in an opposing manner. Therefore, the stepped pivot pin 23 has the small diameter portion 23a fitted into the small diameter pin hole 22b and the large diameter portion 23b fitted into the large diameter pin hole 20c, whereby the hammer support 22 is attached to the holder member 20. The stepped pivot pin 23 is supported so as to be swingable about the swing center.

  As shown in FIG. 5, the large-diameter portions 23b of the stepped pivot pins 23 are fixed from above with set screws 24, thereby ensuring the rattling of the stepped pivot pins 23 in the left-right direction and the vertical direction. Can be prevented. The substantially cylindrical cutter shaft member 7 is fitted inside the hammer support body 22, the hammer connecting body 25 is fixed to the lower end portion of the cutter shaft member 7, and the hammer 8 can be attached to and detached from the lower end of the hammer connecting body 25. Installed.

  Here, as shown in FIGS. 3 and 5, the upper end surface of the hammer 8 abuts on the mounting lower end surface of the hammer coupling body 25, and the positioning pin 8 a provided on the hammer coupling body 25 abuts on the rear end of the hammer 8. In this state, by engaging the engaging portion 8b of the hammer 8 with the hook portion 26a at the lower end portion of the connecting lever 26 rotatably provided on the hammer connecting body 25, the hammer 8 is moved to the lower end portion of the hammer connecting body 25. Are integrally connected to each other.

  An adjustment screw 27 is screwed onto the upper end portion of the connecting lever 26. When the adjustment screw 27 is turned clockwise, the hammer 8 can be firmly pressed and fixed by the hook portion 26a, and the adjustment screw 27 is anti-rotated. When it is turned clockwise, the hook portion 26a is separated from the engaging portion 8b, so that the hammer 8 can be removed.

  As shown in FIG. 5, the lower end portion of the sliding surface (inner peripheral surface) of the hammer support 22, the middle step in the height direction of the outer peripheral surface of the hammer support 22, the holder member 20 and the lower frame 3 a Oil seals 28 to 30 are respectively provided at the contact angle portions. A ring plate 31 is screwed to the lower end of the hammer support 22 at a plurality of locations so that the oil seal 28 is not removed. Therefore, the oil seals 28 to 30 prevent the lubricating oil used in the electronic eyelet stitching sewing machine 1 from dropping downward through the sliding surface between the hammer support 22 and the holder member 20. It has become.

A chamfered portion 7a having a predetermined length is formed on the front side of the upper end portion of the cutter shaft member 7, and a non-rotating pin 32 that comes into contact with the chamfered portion 7a is screwed to the hammer support 22 so that the detent pin 32 is chamfered. By contacting the part 7a, the cutter shaft member 7 is restricted from rotating.
The hammer driving air cylinder 9 for driving the hammer 8 is arranged upward in the leg column portion 4 of the electronic eyelet overlock sewing machine 1, and is configured, for example, as a double-acting type. A lower end portion of the hammer driving air cylinder 9 is pivotally supported by a frame 2a of the bed portion 2 via a pivot pin 34 so as to be rotatable.

  As shown in FIGS. 1 and 2, the transmission mechanism 10 includes a first link member 40 having a substantially crank shape in a plan view and a substantially inverted L shape in a front view. The first link member 40 includes a pivot portion 40a, and the pivot portion 40a is pivotally supported by a first pivot shaft 41 that is fixed to the frame 3a and that faces in the left-right direction. The driving side end 40b of the first link member 40 is formed in a bifurcated shape and is rotatably connected to a connecting portion 9b at the tip of a piston rod 9a extending upward from the hammer driving air cylinder 9.

  The arm portion 3 is provided with a second link member 42 extending in the front-rear direction, and is rotatable about a second pivot shaft 43 in the left-right direction fixed to the frame 3 a at a substantially central portion in the front-rear direction. It is pivotally supported. A projecting portion 42c is formed on the upper side of the center portion in the front-rear direction of the second link member 42, and the height detecting potentiometer 12 for detecting the height position of the hammer 8 is fixed to the frame 3a immediately above the projecting portion 42c. ing. The lower end portion of the detection lever 13 fixed to the drive shaft of the height detection potentiometer 12 is engaged with the pin of the protruding portion 42c. The height detection potentiometer 12 corresponds to detection means for detecting completion of cutting by the buttonhole cutting mechanism 14.

  The front-side pressing-side end portion 42a and the rear-side connecting-side end portion 42b of the second link member 42 are each formed in a bifurcated shape. Between the first and second link members 40 and 42, an intermediate link member 44 having a substantially square shape in side view is disposed. A substantially straight relief hole 44a is formed in a substantially lower half of the intermediate link member 44 in order to allow the cutter shaft member 7 to be lowered to a lower cutting position by manual operation.

  The connection side end portion 40c of the first link member 40 is also formed in a bifurcated shape, and the central portion of the left and right first connection pin 45 attached to the connection side end portion 40c is engaged and connected to the escape hole 44a. ing. The bifurcated connecting side end portion 42b of the second link member 42 and the upper end portion of the intermediate link member 44 are connected by a second connecting pin 46 oriented in the left-right direction. A pressing roller 47 is disposed inside the bifurcated pressing side end portion 42 a of the second link member 42, and is pivotally supported by a pivot shaft 48. The pressing roller 47 is located above the upper end of the cutter shaft member 7. Abut.

  A part of the outer periphery of the pressing roller 47 is chamfered flat, and the flat surface is in surface contact with the upper end of the cutter shaft member 7. As shown in FIG. 4, a notch portion 7b is formed from the rear at the upper end portion of the cutter shaft member 7, and an engagement pin 7c facing in the left-right direction is attached so as to cross the notch portion 7b. ing. A vertical wall portion of an engagement plate 49 bent in a L-shape when viewed from the front is fixed to the rear end portion of the pressing roller 47 with a screw 50, and the horizontal wall portion of the engagement plate 49 is engaged with the engagement pin 7c from below. Is engaged.

  As shown in FIG. 1, a tension coil spring 53 is hung between the engagement pin 51 fixed to the right side surface in the vicinity of the front end of the second link member 42 and the engagement pin 52 fixed to the upper frame 3a. The front end of the second link member 42 is biased upward by the spring force of the tension coil spring 53, and the cutter shaft member 7 is also biased upward via the engagement plate 49.

  The hammer operation of the electronic eyelet stitching machine 1 configured as described above will be briefly described. As shown in FIG. 1, with the piston rod 9a of the hammer driving air cylinder 9 in the advanced state and the cutter shaft member 7 positioned at the raised standby position, the work cloth W is placed on the feed base 16. Position in place. After that, before forming the stitched seam on the work cloth W on the feed base 16, the start / stop switch 17 (see FIG. 9) is operated, and as shown in FIG. The piston rod 9a is driven to retract.

  As a result, the first link member 40 rotates clockwise around the first pivot shaft 41 as the pivot center, and accordingly, the second link member 42 is moved to the second pivot shaft via the intermediate link member 44. It rotates counterclockwise around 43 as a rotation center. Accordingly, the cutter shaft member 7 is pushed down to the lower cutting position via the pressing roller 47 at the pressing side end portion 42 a of the second link member 42. At this time, the work cloth W is pressed against the fixed blade 5 by the hammer 8, and a button hole is cut and formed inside the hole stitching formation scheduled portion of the work cloth W.

When the first link member 40 rotates clockwise around the first pivot shaft 41 as a result of the retraction of the piston rod 9a of the hammer driving air cylinder 9, as shown in FIG. A triangle is formed by the center X of the support shaft 41, the center Y of the first connecting pin 45, and the center Z of the second connecting pin 46, thereby forming a toggle mechanism (so-called boost mechanism).
Due to the clockwise rotation of the first link member 40, the opening angle α between the side XY consisting of X and Y and the side YZ consisting of Y and Z becomes larger than the retraction driving force of the piston rod 9a. A force that pushes up the second connecting pin 46 with a large torque is generated.

When the piston rod 9a of the hammer driving air cylinder 9 is advanced from the state shown in FIG. 7, the first link member 40 rotates counterclockwise as shown in FIG. At this time, the first link pin 45 of the link side end 42b of the first link member 40 only moves downward in the escape hole 44a, and does not pull down the intermediate link member 44 downward.
The cutter shaft is connected via the engagement plate 49 and the engagement pin 7c at the same time as the second link member 42 is rotated clockwise by the spring force of the tension coil spring 53 mounted on the second link member 42. After the member 7 is pulled up to the upper standby position and the feed base 16 moves to the sewing start position, the hole sewing is executed.

  When the second link member 42 is at the non-rotating position shown in FIG. 1 and the hammer 8 is at the uppermost position, the output value of the height detecting potentiometer 12 is the maximum volume value Vmax. When the second link member 42 is at the maximum swing position shown in FIG. 7 and the hammer 8 is switched to the punching position where the fixed blade 5 is pressed, that is, the cloth on which the work cloth W is not set on the feed base 16. When the thickness is “0”, the output value of the height detecting potentiometer 12 via the swing of the detecting lever 13 is the reference volume value V0.

  A presser drive mechanism 60 for switching and driving the presser foot 65 that presses and holds the work cloth W on the upper surface of the feed base 16 between the press position and the release position will be described with reference to FIG. However, the presser foot drive mechanism 60 includes a right side presser foot drive mechanism 60A on the right side of the rear end portion of the feed base 16 and a left side presser foot drive mechanism 60B on the left side of the rear end portion of the feed base 16. The right presser driving mechanism 60A will be described.

  On the upper surface on the right side of the rear end portion of the feed base 16, the pivotal support portion of the swing lever 61 is pivotally attached to the left and right pivot support shafts 62 via a pivot support block 63. The rear end portion of the presser foot 64 is fixed to the upper end portion of the swing lever 61 by a bolt, and the center portion in the front-rear direction of the presser foot 65 is pivoted to the front end portion of the presser foot lever 64 by a pivot bolt 66. It is worn.

  A connecting portion 61 a bent in a U shape is formed at the lower end of the swing lever 61. The upper end portion of the clamp lever 72 is fixed to the outer side of the connecting shaft 67 in the left-right direction, the rear end portion of the presser driving lever 68 is fixed to the inner side of the connecting shaft 67, and the front end portion of the presser driving lever 68 is connected. It is connected to the part 61a.

  A presser air cylinder 69 is provided rearward on the lower side of the feed base 16, and the rear end portion of the presser air cylinder 69 is swung up and down by a left and right pivot pin 70 supported by the frame of the feed base 16. It is pivotally possible. A block-like connecting member 71 is fixed to the rear end portion of the piston rod 69 a extending rearward from the presser air cylinder 69, and the lower end portion of the clamp lever 72 is rotated by the pivot pin 73 at the rear end portion of the connecting member 71. It is pivotally supported.

When the piston rod 69a of the presser air cylinder 69 is driven to retract, the upper end portion of the swing lever 61 moves backward via the clamp lever 72 and the presser drive lever 68 as shown by the solid line in FIG. The right presser foot 65 is raised to the upper retracted position.
When the piston rod 69a of the presser air cylinder 69 is driven forward, the upper end of the swing lever 61 moves forward as shown by a two-dot chain line in FIG. It descends and presses the upper surface of the feed base 16.

The outline of the control system of the electronic eyelet over-locking sewing machine 1 will be described with reference to the block diagram of FIG.
The control device 80 of the electronic eyelet hole sewing machine 1 corresponds to control means. The control device 80 is composed of a microcomputer including a CPU 81, a ROM 82, a RAM 83, an input interface 85, an output interface 86, and the like connected to these via a bus 84 such as a data bus.

  Various signals are input to the input interface 85 from the start / stop switch 17, the height detection potentiometer 12, the timing signal generator 87, and the like, and operation instruction signals from an operation panel 88 (not shown) are supplied. Is done. The timing signal generator 87 is provided so as to be linked to the main shaft (not shown) of the electronic eyelet stitching machine 1, detects the rotational phase of the main shaft, and outputs various phase signals.

  From the output interface 86, a drive circuit 90 for the sewing machine motor 89, a drive circuit 92 for the θ-direction drive motor 91 for driving the needle bar turning mechanism, and a hammer drive air cylinder 9 for driving the hammer 8 are provided. A drive circuit 94 for the electromagnetic switching valve 93, a drive circuit 95 for the presser air cylinder 69, a drive circuit 97 for the X-direction drive motor 96 for moving and driving the feed base 16, and a Y-direction drive motor 98. A drive signal is appropriately supplied to the drive circuit 99 for this and the drive circuit 101 for the air pressure regulator 100, and a display drive signal is supplied to the display and lamp of the operation panel 88.

  The air pressure adjuster 100 is for adjusting the pressure of pressurized air supplied to the hammer driving air cylinder 9 and adjusts the air pressure according to the voltage applied from the drive circuit 101. In addition, the air pressure increases as the applied voltage increases.

The ROM 86 has a hammer data in addition to a sewing data for a sewing machine for driving a sewing mechanism based on the sewing data for a plurality of types of seam stitches and various types of the sewing data. The drive air cylinder 9, motors 91, 96, 98 and various drive control programs for driving the air pressure regulator 100 are stored.
The RAM 83 is provided with various work memories, buffers, and the like in addition to the stitch data memory for storing the read sewing data of the hole stitch.
The CPU 81 executes various processes in accordance with the programs stored in the ROM 86.

The above-described control device 80 controls the cutting force to be changed according to the cutting length of the button hole that is scheduled to be cut, and the cutting length is variously fixed as shown in FIG. It is calculated according to the blade 5 (female numbers 1 to 5) and the contact length L. This calculation method will be described. For example, it is assumed that there are fixed blades 5 of female numbers 1, 2, 3, 4, and 5 as fixed blades 5 that can be exchanged with the electronic eyelet stitching machine 1. For example, the radius of the eyelet part 5a of the fixed blade 5 is R, the angle T between the eyelet part 5a and the leg part 5b is, for example, uniformly 30 °, the length of the eyelet part 5a is A, and the outer peripheral length of the eyelet part 5a. Is B and the contact length L of the hammer 8 with the fixed blade 5 is L, the cutting length S [mm] is:
S = LA-B
Here, B = (2/3) × 2πR + 2 × 1.73 × R
Since the fixed blade 5 of the female number 1 has R = 1.0 [mm] and A = 3.0 [mm], the cutting length S is “L + 4.65” [mm].

  Hereinafter, the cutting length S of the fixed blade 5 with the knife number 2 is “L + 5.58” [mm], and the cutting length S of the fixed blade 5 with the knife number 3 is “L + 6.51” [mm], the knife number. The cutting length S of the fixed blade 5 of 4 is “L + 7.44” [mm], and the cutting length S of the fixed blade 5 of the female number 2 is the radius R = 0 (because of the linear form), “L” [mm].

Each knife number and dimension data (the radius R, the angle T, and the length A) of the fixed blade 5 with the knife number are stored in the ROM 82.
In this case, the user may input the cutting length S from the input key of the operation panel 88 every time sewing is performed.

  FIG. 14 shows a preferable relationship among the cutting length S, the air pressure, and the driving voltage Vo. For example, when the cutting length S is “10 mm”, the air pressure is “0.2 MPa”, and the drive voltage Vo for obtaining this air pressure “0.2 MPa” is “2.8 V”. The air pressure is increased as the cutting length S increases. The ROM 82 stores a relational expression (1) with the drive voltage Vo corresponding to the cutting length S, and a preferable driving voltage Vo can be obtained from the cutting length S.

Vo = (1.8 / 50) × (S−10) +2.8 (1)
FIG. 15 is a graph showing this relational expression (1).
Next, the hole stitching control by the point knife executed by the control device 80 of the electronic eyelet hole stitching sewing machine 1 will be described based on the flowchart of FIG. In the control of the hole stitching by the point knife, the button hole is cut and formed by driving the hammer 8 prior to the hole stitching by specifying the point knife.

A hole stitch to be used for sewing is selected on the operation panel 88, and the user inputs the knife number of the fixed blade 5 and the contact length L of the hammer 8 with the fixed blade 5 described above, and the start / stop switch 17 is set. When operated ("YES" in step S1), this control is started. First, the presser air cylinder 69 is driven to advance (step S2). As a result, the cloth presser 65 descends and presses the work cloth W on the feed table 16.
In step S3, the drive voltage Vo is obtained from the input knife number of the fixed blade 5 and the contact length L of the hammer 8 with the fixed blade 5 described above.
In the next step S <b> 4, the drive voltage Vo is applied to the air pressure regulator 100.

In the next step S5, the hammer driving air cylinder 9 is driven back and forth. As a result, the hammer 8 is lowered.
In step S6, it is determined whether the hammer 8 has detected completion of cutting. This detection method of completion of cutting detects the descending position of the hammer 8 based on a change in the volume value from the height detection potentiometer 12, and cuts when the volume value from the height detection potentiometer 12 no longer changes ( Punching) Judged to be complete.

If "YES" is determined in the step S6, the hammer driving air cylinder 9 is driven to advance in a step S7.
In the next step S8, it is detected by the height detecting potentiometer 12 whether or not the hammer 8 has returned to the uppermost position. When the hammer 8 returns to the uppermost position, the process proceeds to step S9 and the feed base 16 is set to the sewing start position. Moving.

  In the next step S10, after the feed base 16 is moved to a predetermined sewing start position, a stitched seam is formed around the button hole by the vertical movement of the sewing needle. When this hole sewing process is completed, in step S11, the presser air cylinder 69 is driven to retreat, and the presser foot 65 is raised to the upper open position, and this control is ended.

  According to this embodiment, the cutting force of the button hole cutting mechanism 14 can be changed by controlling the button hole cutting mechanism driving means 18 by the control device 80. The control device 80 drives the button hole cutting mechanism so as to increase the driving voltage Vo to the air pressure regulator 100 and increase the cutting force when the button hole cutting length S is longer than when the button hole cutting length S is shorter. Since the means 18 is controlled, when the cutting length S of the button hole is long, the cutting force can be strengthened so as not to cause insufficient cutting, and when the button hole is short, excess cutting force can be eliminated, The consumption and deterioration of the fixed blade 5 and the hammer 8 of the buttonhole cutting mechanism 14 can be reduced without causing insufficient cutting.

  In the present embodiment, a height detecting potentiometer 12 for detecting completion of cutting by the buttonhole cutting mechanism 14 is provided, and when the control device 80 detects completion of cutting by the height detecting potentiometer 12. Since the cutting operation of the buttonhole cutting mechanism 14 is controlled to be stopped, the cutting operation of the buttonhole cutting mechanism can be stopped immediately upon detecting the completion of cutting, and the cutting operation of the buttonhole cutting mechanism 14 is performed. It is possible to reduce wear and deterioration of the buttonhole cutting mechanism 14 without being prolonged, and to quickly shift to, for example, the next sewing operation.

  According to the present embodiment, the cutting length S is determined according to the type of the fixed blade 5 (for example, knife numbers 1 to 5) and the contact length L of the hammer 8 with respect to the fixed blade 5. From this, if the type of the fixed blade 5 and the contact length L of the hammer 8 with respect to the fixed blade 5 are known, the cutting length S can also be easily determined, and the type of the fixed blade 5 and the fixed blade 5 of the hammer 8 are determined. The cutting force can be easily changed according to the cutting length S in accordance with the contact length L with respect to.

Further, according to the present embodiment, since the detection means for detecting the completion of cutting is constituted by the height detecting potentiometer 12 which is a detector for detecting the height of the hammer, the completion of cutting can be detected with a simple configuration. .
In addition, according to the present embodiment, the cutting length S is configured by the length of the eyelet portion 5a and the leg portion 5b. Therefore, when the button hole is a eyelet hole, the cutting length S is the eyelet length. Appropriate length considering the hole and appropriate cutting force can be set.

The present invention is not limited to the above embodiment, and may be modified as follows.
(1) In the above embodiment, the cutting length S is determined by the type of the fixed blade 5 and the contact length L of the hammer 8 with respect to the fixed blade 5, but the second embodiment of the present invention. As shown in FIG. 16 as an example, in the case of a sewing machine in which the contact length L of the hammer 8 with respect to the fixed blade 5 is always a fixed length, depending on the type of the fixed blade 5 (for example, female numbers 1 to 5) What is necessary is just to set the cutting length S of a button hole. Since the length of the blade portion of the fixed blade 5 is known in its type, when the contact length L is a fixed length, the cutting length S can be easily set according to the type of the fixed blade 5. It can be set and the cutting force can be easily changed.

(2) When the fixed blade 5 is a sewing machine having a constant length, the button hole cutting length S may be set according to the contact length L of the hammer 8 with respect to the fixed blade 5. . As shown in FIG. 17 showing the third embodiment of the present invention, when the fixed blade 5 has a fixed length K, the contact length L (L1, L2) of the hammer 8 with respect to the fixed blade 5 is If it is known, the cutting length S is also known, so that it is easy to change the cutting force when the fixed blade 5 has a fixed length.
(3) When the eyelet sleep hole is cut and formed as the button hole, as shown in FIG. 18 shown as the fourth embodiment of the present invention, the sub hammer 103 in a form of contacting only the leg portion 5b of the fixed blade 5 is provided. In this case, the length HL of the sub hammer 103 becomes the contact length L and the cutting length S.

(4) The cutting length S may be set based on the type of the fixed blade, the contact length of the hammer with respect to the fixed blade, etc., or the cutting length S may be directly input. .
(5) A detector for detecting the height of the hammer includes a plurality of slits 7d formed at predetermined minute intervals in the vertical direction on the cutter shaft member 7A, as shown in FIG. 19 as a fifth embodiment of the present invention. You may comprise from the proximity sensor 11 which can detect this slit 7d. The proximity sensor 11 detects the movement of the plurality of slits 7d according to the vertical movement of the cutter shaft member 7A, and detects the height position of the hammer 8.

(6) In addition to the cutter shaft member 7A, the detectors for detecting the height of the hammer include the piston rod 9a of the hammer driving air cylinder 9, the first link member 40, the second link member 42, etc. You may make it detect the movement amount or rotation amount of the various members relevant to a motion.
(7) The button hole cutting mechanism driving means may be configured to employ a rotating type that rotates the hammer 8 via a pivot shaft.

Sectional drawing of the right side surface which shows the internal structure of the electronic eyelet hole sewing machine which concerns on 1st Example of this invention Top view showing the internal structure of an electronic eyelet overlock sewing machine Partial enlarged right side view of cutter shaft member support structure Partial plan view of support structure of cutter shaft member Partial front view of cutter shaft member support structure Exploded perspective view of holder member and hammer support Figure 1 equivalent when cutting the work cloth Enlarged side view of the presser foot and presser foot drive mechanism Block diagram of the control system of an electronic eyelet overlock sewing machine Plan view showing the cutting edge shape of a fixed blade Flowchart of over-lock stitching control with point knife Diagram showing the relationship between the cutting edge length of the fixed blade type, the contact length of the hammer with the fixed blade, and the cutting length Diagram for explaining the cutting edge dimensions and contact length of the fixed blade The figure which shows the preferable relationship between cutting length S, air pressure, and drive voltage Vo. Graph showing the relationship between cutting length S and air pressure 2A and 2B show a second embodiment of the present invention, in which FIG. 4A is a plan view of a fixed blade and a hammer with a female number 1, FIG. 4B is a plan view of a fixed blade and a hammer with a female number 4, and FIG. Top view of number 5 fixed blade and hammer FIGS. 3A and 3B show a third embodiment of the present invention, in which FIG. 3A is a plan view of a fixed blade and a hammer when the contact length is relatively long, and FIG. Top view of blade and hammer FIG. 10 equivalent view showing the fourth embodiment of the present invention. FIG. 3 equivalent view showing a fifth embodiment of the present invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 is an electronic eyelet sewing machine, 5 is a fixed blade, 8 is a hammer, 9 is a hammer drive air cylinder, 10 is a transmission mechanism, 12 is a height detection potentiometer (detection means, detector), 14 is a button hole A cutting mechanism, 15 is a fixed blade base, 18 is a button hole cutting mechanism driving means, 80 is a control device (control means), and W is a work cloth.

Claims (7)

A button hole cutting mechanism for cutting and forming a button hole in a work cloth, a button hole cutting mechanism driving means for driving the button hole cutting mechanism, and a button hole cutting mechanism driving means for changing the cutting force of the button hole cutting mechanism Control means for controlling
The perforated sewing machine characterized in that the control means controls the button hole cutting mechanism driving means so as to increase the cutting force when the button hole cutting length is longer than when the button hole cutting length is short. Comprising detection means for detecting completion of cutting by the buttonhole cutting mechanism;
The hole stitching sewing machine according to claim 1, wherein the control means controls to stop the cutting operation of the button hole cutting mechanism when the detection means detects the completion of cutting. The buttonhole cutting mechanism is composed of a fixed blade and a movable hammer,
The buttonhole cutting mechanism driving means is constituted by a driving mechanism for driving the hammer,
3. The perforated sewing machine according to claim 1, wherein the cutting length is determined according to a type of the fixed blade and a contact length of the hammer with respect to the fixed blade. The buttonhole cutting mechanism is composed of a fixed blade and a movable hammer,
The buttonhole cutting mechanism driving means is constituted by a driving mechanism for driving the hammer,
3. The perforated sewing machine according to claim 1, wherein when the contact length of the hammer with respect to the fixed blade is a fixed length, the length of the button hole is set according to the type of the fixed blade. The buttonhole cutting mechanism is composed of a fixed blade and a movable hammer,
The buttonhole cutting mechanism driving means is constituted by a driving mechanism for driving the hammer,
3. The hole stitching according to claim 1, wherein when the fixed blade has a certain length, the cutting length of the button hole is determined according to the contact length of the hammer with the fixed blade. sewing machine.   The perforated stitching machine according to any one of claims 1 to 5, wherein the cutting length is constituted by the length of the eyelet portion and the leg portion.   7. The perforated sewing machine according to claim 2, wherein the detecting means comprises a detector for detecting the height of the hammer.

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