eyelet sewing machine

Abstract

A hole sewing machine (100), comprising: a needle vertical movement mechanism (20) that moves a sewing needle (1) up and down; a movement mechanism (270) that moves the sewing needle (1) relative to a fabric along a direction perpendicular to a longitudinal direction of a buttonhole (B); a transport mechanism (70) that moves the fabric relative to the sewing needle (1) along the longitudinal direction of the buttonhole (B); a bobbin thread cutting mechanism (50) that is provided below the fabric at the time of sewing and cuts a bobbin thread; and a bobbin thread catching mechanism (80) that is provided below the bobbin thread cutting mechanism (50) and catches the bobbin thread, the bobbin thread catching mechanism (80) comprising: a thread catching member (85) that catches the bobbin thread;andan adjusting unit (89) which adjusts a stop position of the thread catching member (85) in the direction perpendicular to the longitudinal direction of the buttonhole (B) at the time of catching the lower thread;

Description

BACKGROUND OF THE INVENTIONField of the invention

[0001] The invention relates to a hole sewing machine. State of the art

[0002] The eyelet sewing machine comprises a needle oscillation mechanism for performing needle oscillation along a direction perpendicular to a longitudinal direction of a buttonhole, a fabric feeding mechanism for moving a fabric along the longitudinal direction of the buttonhole, a bobbin thread cutting mechanism provided below a throat plate for cutting the bobbin thread at the time of completion of the sewing operation, and a bobbin thread catching mechanism provided below the bobbin thread cutting mechanism for catching the bobbin thread in place.

[0003] At the time of sewing, with the fabric moving along the buttonhole by the fabric feeding mechanism, the sewing needle is moved up and down to perform the sewing operation in a zigzag manner, while the needle oscillation around the buttonhole is performed by the needle oscillation mechanism, and when the stitch of the last needle on the side of one end part of the buttonhole is completed, the bobbin thread catching mechanism holds the bobbin thread in place and the cutting of the bobbin thread is performed by the bobbin thread cutting mechanism.

[0004] In the bobbin thread catching mechanism, a thread catching plate having a recessed notch and a pulling plate for bringing the bobbin thread closer to the thread catching plate side come into sliding contact with each other in a direction of mutual approach, whereby the bobbin thread is held in the deepest part of the recessed notch (see, for example, JP 2000 - 271 371 A).

[0005] DE 10 2012 205 049 A1 discloses a thread-cutting assembly for a buttonhole sewing machine. DE 10 2004 015 813 B3 describes an eyelet buttonhole sewing machine. Devices for cutting a bobbin thread in a sewing machine are known from JP 2000 - 300 885 A and DE 100 13 799 A1. DE 10 2007 056 132 A1 describes a sewing machine. Summary of the invention

[0006] However, in the related eyelet sewing machine, the catching position of the bobbin thread is determined by the bobbin thread catching mechanism on the extension line of the buttonhole.

[0007] In contrast, the position of the last needle of the hole sewing process can be on the left side or on the right side of the buttonhole without being limited to the extension line of the buttonhole.

[0008] In this way, when the position of the last needle is on the left or right side of the buttonhole relative to the extension line, the bobbin thread, which is guided between the fabric and the bobbin thread catching position by the bobbin thread catching mechanism, assumes a tilted state. Accordingly, the remaining end portion of the bobbin thread on the fabric side has a large length after being cut by the bobbin thread cutting mechanism.

[0009] The object of the present invention is to provide a hole sewing machine which is capable of shortening the remaining end portion of the bobbin thread. (1) A hole sewing machine includes a needle vertical movement mechanism, a moving mechanism, a feeding mechanism, a bobbin thread cutting mechanism, and a bobbin thread catching mechanism. The needle vertical movement mechanism moves a sewing needle up and down. The moving mechanism moves the sewing needle relative to a fabric along a direction perpendicular to a longitudinal direction of a buttonhole. The feeding mechanism moves the fabric relative to the sewing needle along the longitudinal direction of the buttonhole. The bobbin thread cutting mechanism is provided below the fabric at the time of sewing and cuts a bobbin thread. The bobbin thread catching mechanism is provided below the bobbin thread cutting mechanism and catches the bobbin thread. The bobbin thread catching mechanism includes a thread catching member and an adjusting unit. The thread catching member catches the bobbin thread.The setting unit sets a stop position of the thread catching link in the direction perpendicular to the longitudinal direction of the buttonhole at the time of catching the lower thread. (2) In the openwork sewing machine according to (1), the adjustment unit is a stopper that determines the stop position of the thread-catching link. The stopper is used to change and adjust the contact position between the stopper and the thread-catching link. (3) In the eyelet sewing machine according to (1), the bobbin thread catching mechanism includes a catching actuator that controls the thread catching member to catch the bobbin thread. The adjusting unit adjusts the stop position of the thread catching member in the direction perpendicular to the longitudinal direction of the buttonhole by controlling the catching actuator. (4) The eyelet sewing machine according to (3) further comprises a control device. The control device controls the needle vertical movement mechanism, the movement mechanism, and the transport mechanism to perform eyelet sewing around the buttonhole or a predetermined buttonhole formation position. The adjustment unit controls the catching actuator to bring the stop position of the thread catching member closer to the same direction as a stitching position of the last needle of the eyelet sewing at the buttonhole or the predetermined buttonhole formation position.

[0010] The hole-stitching machine according to the invention has the adjusting unit configured to adjust the stop position of the thread catching member for catching the bobbin thread in the direction perpendicular to the longitudinal direction of the buttonhole at the time of catching, even when a stitch of the last needle of the hole-stitching on the buttonhole is performed in one of the directions perpendicular to the longitudinal direction of the buttonhole; therefore, it is possible to catch the bobbin thread in the same direction, reduce the inclination of the bobbin thread guided between the catching position and the fabric to approximate it to a vertical state, and further shorten the end portion remaining after cutting the bobbin thread. Short description of the characters Fig. 1 is a perspective view of a hole sewing machine embodying the invention; Fig. 2 is a schematic diagram of the internal configuration of the hole sewing machine; Fig. 3 is a bottom view of a bobbin thread catching mechanism and a bobbin thread cutting mechanism; Fig. 4 is a cross-sectional view of a thread catching member and a thread pulling member of the lower thread catching mechanism; Fig. 5 is a perspective view of the periphery of a stopper of the lower thread catching mechanism; Fig. 6A is an explanatory view showing a state in which a stop position of the thread catching member is set to the right by the stopper; Fig. 6B is an explanatory view showing a state in which the stop position of the thread catching member is set to the left by the stopper; Fig. 7A is an explanatory view showing a stitch of the last needle; Fig. 7B is an explanatory view showing a catching position of the thread catching member in which the stop position is set to correspond to the stop position of the last needle; Fig. 8A is an explanatory view showing a stitching position of the last needle; Fig. 8B is an explanatory view showing a catching position of the thread catching member in which the stop position is set to correspond to the stitching position of the last needle; Fig. 9A is an explanatory view showing a stitching position of the last needle; Fig. 9B is an explanatory view showing a catching position of the thread catching member in which the stitching position is set to correspond to the stitching position of the last needle; Fig. 10 is a block diagram showing a control system of the eyelet sewing machine; Fig. 11A is a plan view of a collar which is another example of an adjusting unit; Fig. 11B is a front view thereof; Fig. 12 is a partially cross-sectional view of the adjusting body, which is another example of the adjusting unit; and Fig. 13 is a bottom view of another example of the bobbin thread catching mechanism. Detailed description[Summary of the eyelet sewing machine]

[0011] Hereinafter, a hole sewing machine 100 according to the invention will be described with reference to the accompanying drawings. Fig. 1 is a perspective view of the eyelet sewing machine 100 and Fig. 2 is a schematic view of the internal configuration. In the following description, a fabric transport direction is referred to as a horizontal direction and a direction of the hole sewing machine 100 as the Y-axis direction, a direction as a horizontal direction and a direction perpendicular to the Y-axis direction is referred to as the X-axis direction, and a vertical direction is referred to as the Z-axis direction. Further, if necessary, as shown in Fig. 1, which refers to one direction in the Y-axis direction as "front," while the other direction is referred to as "back." Furthermore, one direction in the X-axis direction is referred to as "right," while the other direction is referred to as "left."

[0012] The openwork sewing machine 100 comprises a fabric feed mechanism 70, which is equipped with a feed plate 71 as a support area for placing a fabric and serves as a feed mechanism for feeding the fabric by moving the feed plate 71 along a fixed feed direction (hereinafter referred to as the "fabric feed direction (Y-axis direction)"), a needle vertical movement mechanism 20 for vertically moving a sewing needle 1, a needle oscillation mechanism 270 as a movement mechanism for moving the sewing needle along a direction perpendicular to the feed direction (X-axis direction), a presser foot 41 as a pressing member for holding the fabric from above on the feed plate 71; a presser mechanism 40, which holds the fabric on the feed plate 71 through the presser foot 41; a knife mechanism 60, which forms a buttonhole for performing the openwork sewing process on the fabric, a thread tensioner 11,which imparts tension to the upper thread, a shuttle mechanism which interlaces the lower thread with the upper thread, an upper thread cutting device (not shown) for cutting the upper thread, a lower thread cutting mechanism 50 for cutting the lower thread, a lower thread catching mechanism 80 which catches the lower thread, a control device 90 which carries out the operation control of the respective units, and a sewing machine frame 101 which accommodates and supports each of the above-mentioned configurations. Furthermore, the eyelet sewing is performed on the fabric placed on the feed plate 71 (on a support area) through the cooperation of the fabric feed mechanism 70 (a feed mechanism), the needle vertical movement mechanism 20, and the needle oscillation mechanism 270.

[0013] The thread tensioner 11 and the upper thread cutting device of the openwork sewing machine 100 are structurally identical to conventional, well-known configurations; therefore, they will not be described in detail.

[0014] Furthermore, the eyelet sewing machine 100 is a sewing machine suitable for sewing the fabric formed with a hole for performing eyelet sewing. Furthermore, although the hole may be suitable for any hole requiring eyelet sewing, without being limited to a buttonhole, a buttonhole extending along the Y-axis direction is illustrated here. [Sewing machine frame]

[0015] The sewing machine frame 101 is configured to include a bed portion 102, which is a lower portion of the openwork sewing machine 100 and extends along the Y-axis direction, an upright body portion 103, which is erected from the rear end portion of the bed portion 102, and an arm portion 104, which extends from the upper end portion of the upright body portion 103 along the Y-axis direction.

[0016] The bed area 102 is formed in a shape substantially resembling a rectangular cuboid, and the longer side of the rectangular upper surface area extends along the Y-axis direction. Furthermore, the upper surface of the bed area 102 serves as a work area on which the textile is placed at the time of sewing.

[0017] The upright body portion 103 is arranged closer to the left side, on the side of the rear end portion of the upper surface of the bed portion 102. Thus, almost a right half of the upper surface of the bed portion 102 can serve as a work area on which the textile is placed over the entire length of the Y-axis direction.

[0018] The arm portion 104 extends forward from the upper end portion of the upright body portion 103 to near the front end portion of the bed portion 102. In the following description, the end surface of the front end portion of the arm portion 104 is assumed to be the surface portion 105. [Needle vertical movement mechanism]

[0019] The needle vertical movement mechanism 20 has the function of mediating the vertical movement operation of a needle bar 21 that holds the sewing needle 1. Through a needle oscillation mechanism 270 provided together with the needle vertical movement mechanism 20, the needle bar 21 further performs a swinging motion along the X-axis direction while performing the vertical movement, and the sewing needle 1 performs needle oscillation. As shown in Fig. 2, the needle vertical movement mechanism 20 comprises the needle bar 21 which holds the sewing needle 1 at the lower end portion, a sewing machine motor 22 as a servo motor which serves as a drive source for the vertical movement of the needle bar 21, an upper shaft 23 which is directly connected to the output shaft of the sewing machine motor 22, a counterweight 24 which is fixedly arranged at the front end portion of the upper shaft 23, and a crank rod 25 which is connected at its upper end portion at a position which is eccentric to the rotation center of the counterweight 24.

[0020] The upper shaft 23 is rotatably supported inside the arm portion 104 in a state extending along the Y-axis direction. Furthermore, an output shaft of the sewing machine motor 22 is connected to the upper shaft 23.

[0021] At its lower end, the crank rod 25 is rotatably connected to the needle bar 21 via the needle bar holder 31 to rotate about the Y-axis. Therefore, when the counterweight 24 rotates via the upper shaft 23 by the drive of the sewing machine motor 22, the upper end of the crank rod 25 connected at the eccentric position performs the circular motion, but only the vertical reciprocating motion along the needle bar 21 is transmitted to its lower end. [Needle oscillation mechanism]

[0022] The needle oscillation mechanism 270 comprises a swing table 26 which supports the needle bar 21 to allow the reciprocating movement along the longitudinal direction, a needle oscillation motor 27 (see Fig. 10) which serves as a drive source for the needle oscillation, an oscillating shaft 28 which carries out the reciprocating rotation by the needle oscillation motor 27, and an oscillating arm 29 which is fixedly mounted on the front end portion of the oscillating shaft 28 in order to impart the oscillating movement to the oscillating table 26.

[0023] The oscillating table 26 is arranged in the immediate vicinity of the surface region 105 on the inside of the arm region 104, and its upper end portion is swingably supported by a stepped screw 30 extending along the Y-axis direction. The oscillating table 26 vertically slidably supports the needle bar 21 with the side supporting the sewing needle 1 facing downward by means of two metal bearings (not shown) through which the needle bar 21 is inserted.

[0024] The oscillating shaft 28 is rotatably supported in the arm portion 104 in a state extending along the Y-axis direction. The rotational operation is input to the oscillating shaft 28 from its rear end portion side by the needle oscillation motor 27.

[0025] Furthermore, the swing arm 29 is pivotally supported on the front end portion side of the swing shaft 28 with its swing end portion facing downward, and the swing end portion is provided with a square piece 32 in a state rotatable about the Y-axis. The square piece 32 is fitted into the recess of the swing table 26. The recess of the swing table 26 is provided with opposing surfaces that come into sliding contact with the two side surfaces of the square piece 32 extending in the X-axis direction, thereby allowing the positional displacement of the square piece 32 in the Z-axis direction. Thus, when the swing arm 29 swings downward in the X-axis direction, the vibration in the X-axis direction is imparted to the swing table 26, thereby allowing the vertical displacement of the square piece 32.

[0026] Thus, by oscillating the needle bar 21 by a predetermined amount according to the stitch timing of the needle bar 21 by the sewing machine motor 22, it is possible to execute a stitch at any position in the X-axis direction. [Shuttle mechanism]

[0027] The shuttle mechanism includes a lower shaft 33 rotatably supported in the bed portion 102 and extending along the Y-axis direction, a vertical shuttle 34 imparted rotational movement by the lower shaft 33, a main drive gear 35 provided on the upper shaft 23 to transmit torque to the lower shaft 33, a driven gear (not shown) arranged on the lower shaft 33, and a toothed timing belt 36 stretched between the main drive gear 35 and the driven gear.

[0028] The number of teeth of the main drive gear 35 and the driven gear is set such that twice the rotation speed is transmitted from the upper shaft 23 to the lower shaft 33, and at the time of the vertical movement of the sewing needle 1, the vertical shuttle 34 is able to complete two revolutions.

[0029] The vertical shuttle 34 comprises an outer shuttle, which is fixedly mounted on the lower shaft 33 and has a hook, and an inner shuttle, which holds the bobbin case and does not rotate. The vertical shuttle 34 uses a so-called DP shuttle, which is capable of maintaining a perfect stitch pattern on the front and back during any fabric feed. [Knife mechanism]

[0030] The knife mechanism 60 includes a cloth cutting knife 61 which forms a hole (a buttonhole) to perform the hole sewing through a gap along the Y-axis direction, a base member 62 which holds the cloth cutting knife 61, a knife support rod (not shown) which holds the base member 62 at the lower end portion and is supported by the arm portion 104 to be vertically movable, and a solenoid 63 (see Fig. 10) as a drive source which imparts the vertical movement to the material cutting knife 61 via the knife holding rod.

[0031] The fabric cutting knife 61 is arranged rearward of the sewing needle 1, in juxtaposition with the sewing needle, and its cutting surface is supported by the base member 62 to be parallel to the YZ plane. Therefore, by lowering the fabric cutting knife 61, it is possible to form the buttonhole extending in the Y-axis direction in the fabric.

[0032] The fabric cutting knife 61 is attachable to and detachable from the base member 62, whereby the formation of a buttonhole with a different size is possible by replacing the fabric cutting knife 61 with a fabric cutting knife 61 with a different tooth width.

[0033] The knife support rod is always biased upwards by a tension spring (not shown) and the solenoid 63 is designed to lower the fabric cutting knife 61 during cutting against the tension spring. [Material feed mechanism]

[0034] The fabric feed mechanism (feed mechanism) 70 includes a rectangular feed plate 71 disposed on the upper surface of the bed portion 102, a feed base 73 slidably supported in the bed portion 102 along the Y-axis direction by the two guide shafts 72 and 72, a feed motor 74 serving as a drive source of the fabric feed in the Y-axis direction, and a timing belt 76 stretched between the two pulleys 75 and 75.

[0035] The two guide shafts 72 and 72 are fixed and supported in the bed area 102 and extend parallel to the Y-axis direction.

[0036] The transport plate (support portion) 71 is arranged with its long side on the upper surface of the bed portion 102 so as to be parallel to the Y-axis direction, and is penetrated in the vertical direction in a substantially central region in the X-axis direction near its front end portion by an elongated hole 711 extending along the Y-axis direction. The elongated hole 711 is formed to be sufficiently wider than the needle oscillation width, and a needle plate 82 (in Fig. 1 not shown) is formed with a slit-shaped opening portion extending in the Y-axis direction into which the cloth cutting knife is inserted, and below the feed plate 71, a needle hole extending along the X-axis direction is arranged, which allows needle oscillation.

[0037] The transport base 73 is slidably supported by the guide shafts 72 and 72 via a sliding bearing (not shown) and holds the transport plate 71 in its upper region.

[0038] One of the two pulleys 75 and 75 is mounted on the output shaft of the transport motor 74, and the other is rotatably supported on the inner wall of the bed portion 102. Both pulleys 75 and 75 are rotatable about the X-axis direction, and the timing belt 76 stretched between them is arranged in a state extending along the Y-axis direction.

[0039] Further, the timing belt 76 is partially connected to the lower portion of the transport base 73 and the transport motor 74 is rotationally driven, the transport base 73 and the transport plate 71 move via the timing belt 76 in the Y-axis direction.

[0040] Therefore, the fabric held by the presser foot 41 on the upper surface of the feed plate 71 can be subjected to arbitrary movement positioning in the Y-axis direction by the operation control of the feed motor 74. Furthermore, since, as described above, the sewing needle 1 can perform the stitch at any position in the X-axis direction by the needle vertical movement mechanism 20, it is possible to perform the stitch at any position in the XY plane on the fabric through the cooperation of the needle vertical movement mechanism 20 and the fabric feed mechanism 70. [Presser mechanism]

[0041] The presser mechanism 40 includes a presser foot 41 (a pressing member) for pressing the fabric against the upper surface of the transport plate 71, a presser arm 43 for supporting the presser foot 41, a sliding roller 44 as a pressing body for pressing down the presser arm 43, and a pressing motor 49 for raising and lowering the presser foot 41 against the sliding roller 44.

[0042] The press arm 43 is elongated along the Y-axis direction, and its rear end portion is mounted on the upper surface of the transfer plate 71 so as to be rotatable about the X-axis direction. Thus, it is possible to vertically move the presser foot 41, which is mounted on the front end portion of the press arm 43.

[0043] The presser foot 41 is a rectangular flat plate extending along the XY plane, and in its central portion, an opening portion is formed in a region where the eyelet stitching can be formed.

[0044] Because the sliding roller 44 rolls along the upper surface of the press arm 43 along the Y-axis direction, even when the press arm 43 moves along the Y-axis direction, it is possible to transmit the downward pressing force without disturbing the movement. [Lower thread catching mechanism]

[0045] Fig. 3 is a bottom view of the bobbin thread cutting mechanism 50 and the bobbin thread catching mechanism 80.

[0046] As shown, the bobbin thread catching mechanism 80 mainly includes a needle plate base 81 fixedly disposed in the bed portion 102 on the underside of the feed plate 71, the needle plate 82 disposed on the upper surface of the needle plate base 81, a thread pulling member 83 and a thread pulling arm 84 provided on the lower surface side of the needle plate base 81, a thread catching member 85 and a thread catching arm 86 provided on the lower surface side of the needle plate base 81, a transmission link 87 that imparts a rotational force of the thread catching operation to the thread pulling arm 84, and an actuator 56 constructed of a motor, a solenoid, or an air cylinder for vertically advancing and retracting the transmission link 87.

[0047] The needle plate base 81 is a substantially rectangular flat plate extending along the XY plane and formed with an opening portion 811 in its central portion. Further, in the opening portion 811 of the needle plate base 81, the needle plate 82 is arranged in a suspended state. The needle plate 82 is an elongated flat plate extending along the Y-axis direction. The slit-shaped insertion hole extending along the Y-axis direction, into which the cloth cutting blade 61 is inserted, and a slit-shaped needle hole extending along the X-axis direction for permitting needle oscillation are formed through the needle plate to be adjacent to each other. That is, the needle plate 82 is arranged at the stitching position of the needle plate base 81 and at the lowered position of the cloth cutting blade 61.

[0048] The opening portion 811 of the needle plate base 81 is formed in a range capable of allowing the downward movement of the stitch and the cloth cutting knife 61, and on the inside thereof, upper and lower knives 51 and 52 of the lower thread cutting mechanism 50, which will be described later, are arranged, and the opening portion is formed to be wider to also allow the cutting operation using the upper and lower knives 51 and 52.

[0049] The thread-pulling arm 84 is a plate-shaped bell crank extending along the XY plane and is mounted on the rear side of the opening portion 811 of the lower surface of the throat plate base 81 by the stepped screw so as to be rotatable about the Z axis. The base end of the thread-pulling link 83 is fixedly arranged by screws in a rotary arm portion extending substantially forward from the stepped screws serving as the rotary shaft. Further, one end portion of the transmission link 87 is connected to the other rotary arm portion extending substantially rearward from the stepped screw serving as the rotary shaft so as to be rotatable about the Z axis. Further, when performing the bobbin thread catching operation, the tension is input to the left from the transmission link 87, and the thread-pulling arm 84 performs the clockwise rotation operation. Fig. 3 out.

[0050] The thread-pulling arm 84 is formed with a protruding portion 841 projecting forward near the rotation center position. The protruding portion 841 is arranged to abut against a convex portion 861 formed on the outer peripheral portion of the thread-catching arm 86 to be described later. When performing the bobbin thread-catching operation, the protruding portion 841 acts to perform the reverse locking rotation with respect to the thread-pulling arm 84, different from that of the thread-pulling arm 84.

[0051] The thread-pulling member 83 has the shape of an elongated plate along the XY plane, its base end is fixedly connected to the rotation end portion of the thread-pulling arm 84, and its tip end extends substantially forward. Furthermore, the thread-pulling member 83 performs the rotation operation integrally with the thread-pulling arm 84 when the bobbin thread catching operation is performed.

[0052] Before starting the bobbin thread catching operation, the thread pulling member 83 waits on the left side of the needle hole and rotates to the right at the start of the bobbin thread catching operation. Thus, the right edge of the thread pulling member 83 comes into contact with the bobbin thread, making it possible to bring the bobbin thread closer to the side of the thread catching member 85 located on the right side of the thread pulling member.

[0053] The thread catching arm 86 is a plate-shaped bell crank extending along the XY plane and is attached to the right side of the opening portion 811 of the lower surface of the throat plate base 81 by a stepped screw so as to be rotatable around the Z axis. Furthermore, the base end of the thread catching member 85 is fixedly disposed by screws in a rotating arm portion extending substantially forward from the stepped screw serving as a rotating shaft. Furthermore, a tension spring 88 is connected to the other rotating arm portion extending substantially rightward from the stepped screw serving as a rotating shaft, and the tension spring 88 imparts counterclockwise rotation to the thread catching arm 86 in Fig. 3. Furthermore, the opposite end portion of the tension spring 88 is screwed to the throat plate base 81.

[0054] Furthermore, the thread catching arm 86 has a convex portion 861 extending to the left with respect to the step screw serving as a rotation shaft, and the outer peripheral portion of the rear side of the convex portion 861 abuts the projecting portion 841 of the thread pulling arm 84. The function of the convex portion 861 will be described later.

[0055] The thread catching member 85 has the shape of a flat plate along the XY plane, its base end extends linearly backward, it is curved by 90° in the intermediate region, and its tip end has a substantially rectangular shape.

[0056] The tip end of the thread catching member 85 is formed with a V-shaped notch 851 that opens to the left at the left edge portion. When catching the bobbin thread, the thread pulling member 83 rotates clockwise, the thread catching member 85 rotates counterclockwise, the bobbin thread is brought closer to the deepest (rightmost) portion of the notch 851, and the bobbin thread is caught when the right edge portion of the thread pulling member 83 passes through the deepest portion of the notch 851.

[0057] As in Fig. As shown in Figure 4, the thread catching member 85 is located above the thread pulling member 83, and the lower surface of the thread catching member 85 and the upper surface of the thread pulling member 83 come into sliding contact with each other. Thus, when catching the bobbin thread, the bobbin thread is pulled and positioned between the thread pulling member 83 and the thread catching member 85. Thus, downward tension is imparted to the bobbin thread, and the fabric is in a slightly downwardly pulled state. Since the bobbin thread cutting mechanism 50, which will be described later, cuts the bobbin thread in this state, it is possible to shorten the remaining end of the bobbin thread of the fabric.

[0058] Here, a function of the convex portion 861 of the thread catching arm 86 described above will be described.

[0059] As described above, a counterclockwise rotational force is imparted to the thread catching arm 86 by the tension spring 88, and thus the rotational force in the operation direction is imparted to the thread catching member 85 at the time of thread catching.

[0060] On the other hand, a counterclockwise rotational force is input from the transmission link 87 to the thread pulling arm 84, so that the thread pulling member 83 is in a standby position (a position to the left of the needle hole) before the thread catching operation begins. At this time, the protruding portion 841 of the thread pulling arm 84 presses against the convex portion 861 of the thread catching arm 86, pushing the thread catching arm 86 back clockwise against the tension spring 88, and holding the thread catching member 85 in the standby position (the right position with respect to the needle hole).

[0061] Because the clockwise rotational force is inputted from the transmission link 87 to the thread pulling arm 84, at the time of thread catching, the thread catching arm 86 rotates counterclockwise according to the tension of the tension spring 88. Thus, the thread pulling member 83 rotates to the right and, associated therewith, the thread catching member 85 rotates to the left.

[0062] That is, in cooperation with the protruding portion 841 of the thread-pulling arm 84, the convex portion 861 of the thread-catching arm 86 rotates the thread-pulling member 83 in conjunction with the thread-catching member 85 in a direction in which they are brought closer to each other from the state in which they are each in the standby position. Thus, as described above, it is possible to guide and hold the lower thread to the deepest portion of the notch 851 of the thread-catching member 85.

[0063] The bobbin thread catching mechanism 80 is provided with a stopper 89 serving as an adjusting unit for adjusting the stop position in the X-axis direction when catching the bobbin thread by the thread catching member 85. By adjusting the stop position of the thread catching member 85 in the X-axis direction when catching, it is possible to adjust the inclination angle at the time of cutting the bobbin thread.

[0064] An outer periphery of a head 891 of the stopper 89, as shown in Fig. 3 and Fig. 5, is formed by an eccentric screw which abuts the left edge portion of the base end of the thread catching member 85. That is, in the stopper 89, the screw shaft 892, which is screwed into the screw hole formed on the lower surface of the throat plate base 81, is provided at a position eccentric to the center of the head 891. Thus, by performing the rotation operation of the stopper 89, the amount of eccentricity of the head 891 is varied in the X-axis direction, and it is possible to adjust the stop position of the thread catching member 85 at the time of the thread catching operation, as shown in Fig. 6A and Fig. 6B shown.

[0065] Reference numeral 893 denotes a nut which serves as a release stopper of the stopper 89 for performing the rotation adjustment.

[0066] As in Fig. 7A and Fig. 7B, when the eccentricity amount of the head 891 is the same on both the left and right sides in the X-axis direction (neutral position), the stopper 89 can align the stop position of the deepest portion of the notch 851 of the thread catching member 85 at the time of catching with the position just below the distal end of the sewing needle 1 in a state of neither swung left nor right (neutral position).

[0067] Furthermore, as in Fig. 8A and Fig. 8B, when the eccentricity amount of the head 891 is the largest on the left side in the X-axis direction, the stopper 89 can align the stop position of the deepest portion of the notch 851 of the thread catching member 85 at the time of catching with the position just below the distal end of the sewing needle 1 in the largely leftward swung state.

[0068] Furthermore, as in Fig. 9A and Fig. 9B, when the eccentricity amount of the head 891 is the largest on the right side in the X-axis direction, the stopper 89 can align the stop position of the deepest portion of the notch 851 of the thread catching member 85 at the time of catching with the position just below the distal end of the sewing needle 1 in the state swung sharply to the right. [Lower thread cutting mechanism]

[0069] As in Fig. 3, the lower thread cutting mechanism 50 includes an upper knife 51 having a base end connected to the lower surface of the throat plate base 81 and a left front side of the opening portion 811 so as to be rotatable about the Z axis, a lower knife 52 connected to the lower surface of the other end portion of the upper knife 51 so as to be rotatable about the Z axis, a leaf spring 53 connected to the lower surface of the lower knife 52 so as to be rotatable about the Z axis coaxially with the lower knife 52, and a coupling link 54 connecting the upper knife 51 and the thread pulling arm 84 of the lower thread catching mechanism 80 to rotate them in conjunction with each other.

[0070] Furthermore, the upper knife 51, the lower knife 52 and the leaf spring 53 of the lower thread cutting mechanism 50 are arranged on the lower side of the throat plate 82 and on the upper side of the thread pulling member 83 and the thread catching member 85 of the lower thread catching mechanism 80.

[0071] The upper knife 51 has a plate-like shape along the XY plane, and, as described above, its base end is supported by the throat plate base 81 so as to be rotatable around the Z-axis, and the rotation end portion is formed with a cutting edge that cuts the lower thread. The cutting edge of the upper knife 51 is formed to extend substantially along the X-axis direction at the front edge portion of the rotation end portion. Further, before the cutting operation, the cutting edge is in the standby position, which is located to the left rear with respect to the needle hole; at the time of cutting, the upper knife 51 rotates counterclockwise in Fig. 3 and its cutting edge is arranged to approach the left side of the needle hole.

[0072] Further, the rotation operation of the upper knife 51 at the time of cutting is inputted from the thread pulling arm 84 through the coupling link 54.

[0073] The lower cutter 52 has a plate-like shape along the XY plane, and at the rotation end portion extending leftward from the rotation center, the cutting edge for cutting the lower thread is formed in cooperation with the upper cutter 51. The cutting edge of the lower cutter is formed to extend substantially along the X-axis direction at the rear edge portion of the rotation end portion. Further, before the cutting operation, the cutting edge of the lower cutter 52 is in the standby position opposite to the front of the cutting edge of the upper cutter 51, and at the time of cutting, the cutting edge rotates backward with the rotation of the upper cutter 51, and both cutting edges are closed after passing below the lower part of the needle hole to perform the cutting operation.

[0074] The lower cutter 52 is formed with a protruding portion 521 projecting forward at the front edge portion, the protruding portion 521 being engaged with the inner edge portion of the opening portion 811 of the throat plate base 81 by the counterclockwise rotation of the upper cutter 51, and the rotation being carried out in a direction in which the cutting edge is closed with respect to the upper cutter 51.

[0075] The leaf spring 53 has a plate-like shape along the XY plane and a shape in which an extending end portion extending to the left from the rotation center as viewed from the lower part is substantially in line with the rotation end portion of the upper cutter 51. Further, at the time of cutting the lower thread, the rotation end portion of the lower cutter 52 comes between the rotation end portion of the upper cutter 51 and the extending end portion of the leaf spring 53. Thus, cutting of the lower thread is performed between the upper cutter 51 and the lower cutter 52, and the cutting end portion of the lower thread extending from the vertical shuttle 34 is held between the lower cutter 52 and the leaf spring 53.

[0076] The reference number 55 denotes an actuating lever which releases the lower thread by rotating the lower knife 52 in the opening direction of the cutting edge before the start of sewing. [Control system of the eyelet sewing machine]

[0077] Fig. 10 is a block diagram showing a control system of the hole sewing machine 100. The hole sewing machine 100 includes a controller 90 as operation control means for controlling the operation of each of the above-mentioned configurations. Furthermore, the controller 90 includes a ROM 92 for storing various control programs, a CPU 91 for executing the control programs, a RAM 93 serving as a work area of ​​the CPU 91, and an EEPROM 96 that stores the sewing pattern data of the hole sewing and various setting data required for operation control of the sewing machine, and can rewrite the stored contents.

[0078] Furthermore, a sewing machine motor driver 22a, which is connected to the sewing machine motor 22 and an encoder 221 for detecting the rotation angle, a needle oscillation motor driver 27a for driving the needle oscillation motor 27, a feed motor driver 74a for driving the feed motor 74, a press motor driver 49a, which is connected to the press motor 49 and an encoder 46 for detecting the rotation angle, a driver 56a of the actuator 56 for performing the operation for catching the lower thread and the operation for cutting the lower thread, a solenoid driver 63a for driving a solenoid 63 for lifting the cloth cutting knife 61, and a thread tension solenoid driver 111a for driving the thread tension solenoid 111, which serves as a thread tension drive source of the thread tensioner 11, are connected via a (not shown) interface to the CPU 91.

[0079] Further, an operation panel 94 for inputting various setting values ​​related to sewing, for example, for selecting the sewing pattern data of the hole sewing, and a start switch 95 for inputting the sewing start are connected to the CPU 91. [Sewing operation of the eyelet sewing machine]

[0080] The sewing operation of the above-mentioned hole sewing machine 100 will now be described.

[0081] In the sewing pattern data recorded in the EEPROM 96 of the eyelet sewing machine 100, data indicating a stitch position for each needle of the eyelet sewing performed around the buttonhole is recorded.

[0082] Upon reading the predetermined sewing pattern data selected by the operation panel 94 from the EEPROM 96, the CPU 91 of the controller 90 calculates the operation amount of the needle oscillation motor 27 and the feed motor 74 for sequentially performing the needle handling of all the needles from the first needle to the last needle at each stitch position.

[0083] Furthermore, when the start switch 95 is depressed, the CPU 91 starts driving the sewing machine motor 22 to start sewing.

[0084] Further, after starting to drive the sewing machine motor 22, its axial angle is read by the encoder 221, and after reaching the predetermined axial angle, the drive is performed based on the calculated operation amount of the needle oscillation motor 27 and the feed motor 74, the sewing needle 1 is positioned at the target position in the X-axis direction, the textile is positioned at the target position in the Y-axis direction, and the needle handling is performed at the target stitch position for each needle.

[0085] When the needle handling of all stitch positions defined in the sewing pattern data is completed, the CPU 91 stops the sewing machine motor 22.

[0086] For the formation of the buttonhole using the knife mechanism 60, it can be set in advance whether this should be carried out before or after the hole sewing process.

[0087] When the formation before the hole sewing operation is set, the formation of the buttonhole is performed using the knife mechanism 60 before the start of the drive of the sewing machine motor 22 and then a hole sewing seam is formed around the buttonhole.

[0088] When the formation after the hole sewing operation is set, the drive of the sewing machine motor 22 is started earlier, the hole sewing seam is formed around the predetermined buttonhole formation position, and then the buttonhole formation is performed using the knife mechanism 60.

[0089] The CPU 91 performs the cutting of the upper thread and the lower thread.

[0090] Before starting the lower thread cutting operation, the thread pulling member 83 of the lower thread catching mechanism 80 is in the left standby position of the needle hole, and the thread catching member 85 is in the right standby position of the needle hole. Furthermore, based on these conditions, by operating the actuator 56, the thread pulling arm 84 is moved clockwise into Fig. 3 rotates and the thread pulling member 83 is rotated towards the needle hole. Furthermore, the thread catching arm 86 rotates counterclockwise in Fig. 3 in conjunction with the thread pulling arm 84 and the thread catching member 85 rotates in the direction of the needle hole.

[0091] Then, the thread catching member 85 stops rotating at a predetermined position in contact with the stopper 89; however, the thread pulling member 83 continues rotating until it reaches below the needle hole. Accordingly, the bobbin thread is caught in the deepest portion of the notch 851 of the previously stopped thread catching member 85.

[0092] Furthermore, with the clockwise rotation of the thread pulling arm 84, the upper knife 51 of the lower thread cutting mechanism 50 performs counterclockwise rotation from the standby position in Fig. 3 and moves forward toward the needle hole. When the bobbin thread is caught by the bobbin thread catching mechanism 80, the cutting edge of the upper blade 51 and the cutting edge of the lower blade 52 are closed in the bobbin thread cutting mechanism 50, and the bobbin thread stretched between the fabric and the bobbin thread catching mechanism 80 is cut.

[0093] Then, the CPU 91 lifts the presser foot 41 through the presser motor 49 to release the fabric, and the sewing process is completed.

[0094] Here, the stitch position L of the last needle is set as sewing pattern data value as follows: on the extension line of the buttonhole B, as shown in Fig. 7A, on the left side with reference to the extension line of the buttonhole B, as shown in Fig. 8A, and on the right side with reference to the extension line of the buttonhole B, as shown in Fig. 9A shown.

[0095] When the stitch position L of the last needle is set in advance on the extension line of the buttonhole B, the rotation of the stopper 89 is set to the position at which the eccentricity amount of the head 891 of the stopper 89 is the same on the left and right sides. As shown in Fig. 7B, the lower thread caught using the lower thread catching mechanism 80 enters a state in which it extends from the textile substantially along a Z-axis direction toward the thread catching member 85, and in this state, by performing cutting using the lower thread cutting mechanism 50, it is possible to further shorten the remaining end portion of the lower thread on the textile side.

[0096] When the stitch position L of the last needle is set in advance on the left side of an extension line of the buttonhole B, the rotation of the stopper 89 is set to a position at which the eccentricity amount increases to the left of the head 891 of the stopper 89. As shown in Fig. 8B, the lower thread caught using the lower thread catching mechanism 80 enters a state in which it extends from the textile substantially along a Z-axis direction toward the thread catching member 85, and in this state, by performing cutting using the lower thread cutting mechanism 50, it is possible to further shorten the remaining end portion of the lower thread on the textile side.

[0097] Further, it is more desirable to adjust the eccentricity amount of the stopper 89 so that the stitching position L of the last needle is in agreement with the position of the deepest portion of the notch 851 of the thread catching member 85 in the X-axis direction at the time of thread catching.

[0098] When the stitch position L of the last needle is set in advance on the right side of the extension line of the buttonhole B, the rotation of the stopper 89 is set to a position at which the eccentricity amount increases to the right side of the head 891 of the stopper 89. As shown in Fig. 9B, the lower thread caught using the lower thread catching mechanism 80 enters a state in which it extends from the textile substantially along a Z-axis direction toward the thread catching member 85, and in this state, by performing cutting using the lower thread cutting mechanism 50, it is possible to further shorten the remaining end portion of the lower thread on the textile side.

[0099] In this case too, it is more desirable to adjust the eccentricity amount of the stopper 89 so that the stitching position L of the last needle is in agreement with the position of the deepest portion of the notch 851 of the thread catching member 85 in the X-axis direction at the time of thread catching. [Technical effect of embodiments of the invention]

[0100] Since the bobbin thread catching mechanism 80 of the hole sewing machine 100 includes the stopper 89 for adjusting the stop position of the thread catching member 85 in the direction perpendicular to the longitudinal direction of the buttonhole (X-axis direction) at the time of catching the bobbin thread, even when the stitch of the last needle of the hole sewing operation is performed on either side, which are the left and right sides, in the X-axis direction at the buttonhole B, it is possible to catch the bobbin thread in the same direction, the inclination of the bobbin thread passed between the fabric and the catching position is reduced and can be brought closer to an orthogonal angle, and it is possible to shorten the end portion remaining after cutting the bobbin thread.

[0101] In particular, since the adjusting unit for adjusting the stop position of the thread catching member 85 in the X-axis direction at the time of catching the lower thread is constituted by the stopper 89, it is possible to perform the adjustment of the lower thread catching position by a simple operation with a simple configuration.

[0102] By constructing the adjusting unit using the stopper 89, even in an existing openwork sewing machine, an adjusting unit can be provided by a simple modification, and it is possible to easily achieve the effect of shortening the end portion remaining after cutting the lower thread. [Another example of a stopper]

[0103] Although the stopper 89 serving as an adjustment unit is described as an eccentric screw, other elements capable of adjusting the stop position of the thread catching member 85 in the X-axis direction can of course also be used.

[0104] For example, as in Fig. 11A and Fig. 11B, a round collar 89A having a through hole formed at an eccentric position may be provided at the same position as the stopper 89 by a screw 891A. In this case, the eccentricity amount of the thread catching member 85 is changed by loosening the screw 891A to rotate the collar 89A and tightening the screw 891A again. Thus, it is possible to adjust the stop position of the thread catching member 85 in the X-axis direction.

[0105] Furthermore, as in Fig. 12, an adjusting body 89B for performing position adjustment by sliding movement in the X-axis direction may be provided at the same position as the stopper 89.

[0106] This adjusting body 89B is composed of a lower plate portion 891B which comes into close contact with the lower surface of the throat plate base 81, and an upright wall portion 892B which is erected at a right angle from the right end portion of the lower plate portion 891B and extends along the YZ plane, and the right wall surface of the upright wall portion 892B comes into contact with the thread catching member 85 and is stopped at a predetermined position in the X-axis direction.

[0107] In the center of the lower plate portion 891B, an elongated hole 893B extending along the X-axis direction is formed continuously, and the screw 894B is inserted into the elongated hole 893B and fixed to the lower surface of the throat plate base 81.

[0108] In this case, the screw 894B is loosened to adjust the mounting position of the adjusting body 89B in the X-axis direction, and the screw 894B is tightened again. Thus, it is possible to adjust the stop position of the thread catching member 85 in the X-axis direction.

[0109] Furthermore, the adjusting body 89B may be formed, for example, by bending or machining a metal plate by a metalworking method. [Another example of the bobbin thread catching mechanism]

[0110] In the above embodiment, the adjusting unit of the lower thread catching mechanism 80 is illustrated as a stopper 89, which requires adjustment work by a manual operation; however, it may also be configured to include an adjusting unit for adjusting the stop position of the thread catching member 85 by the catching actuator, without being limited thereto.

[0111] For example, as in the case of the Fig.13, the lower thread catching mechanism 80C may be configured as an actuator to include a motor 88C (e.g., a stepping motor, etc.) whose operation amount can be controlled by the CPU 91 of the controller 90, a rotary arm 881C provided on an output shaft of the motor 88C, and a link 882C connecting the rotation end portion of the rotary arm 881C and the right rotary arm portion of the thread catching arm 86. Further, in the case of the lower thread catching mechanism 80C, the projecting portion 841 of the thread pulling arm 84 and the tension spring 88 connected to the thread catching arm 86 are omitted, so that the locking of the thread pulling arm 84 and the thread catching arm 86 by the link structure is not performed; other configurations are identical to those of the lower thread catching mechanism 80.

[0112] Thus, the CPU 91 functions as an adjustment unit, and the deepest portion of the notch 851 of the thread catching member 85 can be arbitrarily positioned in the X-axis direction. Accordingly, it is possible to further shorten the end portion of the bobbin thread remaining after sewing is completed.

[0113] The deepest portion of the notch 851 of the thread catching member 85 at the time of catching the lower thread may be set at the stop position in the X-axis direction, for example, by numerical input via the operation panel 94.

[0114] Further, the CPU 91 of the controller 90 reads the selected sewing pattern data to execute the sewing operation, calculates the stitch position of the last needle in the X-axis direction, determines the stop position of the deepest portion of the notch 851 of the thread catching member 85 in the X-axis direction according to this value, and can control the motor 88C to be at a calculated stop position when the lower thread is caught.

[0115] In this case, the stop position of the deepest portion of the notch 851 of the thread catching member 85 in the X-axis direction is desirably determined to be consistent with the stitching position of the last needle in the X-axis direction; however, the stitching position and the stop position in the left-right direction may be brought closer to each other in the same direction without being completely consistent.

[0116] In these cases, when determining the sewing pattern, the correct cutting of the bobbin thread is performed automatically, and it is possible to drastically reduce the workload of the operator on the sewing machine. [Miscellaneous]

[0117] Here, the fabric feed mechanism 70 for moving the fabric along the Y-axis direction is described as a feed mechanism; however, the invention is not limited to this, and a mechanism for moving the sewing needle 1 in the Y-axis direction may also be provided.

[0118] Furthermore, instead of the needle oscillation mechanism 270, a moving mechanism for moving the textile in the X-axis direction may be provided.

Claims

[1] Eyelet sewing machine (100), comprising: a needle vertical movement mechanism (20) which moves a sewing needle (1) up and down; a moving mechanism (270) which moves the sewing needle (1) relative to a textile along a direction perpendicular to a longitudinal direction of a buttonhole (B); a transport mechanism (70) which moves the textile relative to the sewing needle (1) along the longitudinal direction of the buttonhole (B); a bobbin thread cutting mechanism (50) which is provided below the fabric at the time of sewing and cuts a bobbin thread; and a bobbin thread catching mechanism (80) which is provided below the bobbin thread cutting mechanism (50) and catches the bobbin thread, wherein the bobbin thread catching mechanism (80) comprises: a thread catching member (85) which catches the bobbin thread; and an adjusting unit (89) which adjusts a stop position of the thread catching member (85) in the direction perpendicular to the longitudinal direction of the buttonhole (B) at the time of catching the lower thread. [2] Hole sewing machine (100) according to claim 1, wherein the adjusting unit (89) is a stopper (89) which determines the stop position of the thread catching member (85), and wherein the stopper (89) changes and adjusts a contact position between the stopper (89) and the thread catching member (85). [3] Hole sewing machine (100) according to claim 1, wherein the lower thread catching mechanism (80) comprises a catching actuator which controls the thread catching member (85) to catch the lower thread, and wherein the adjusting unit (89) adjusts the stop position of the thread catching member (85) in the direction perpendicular to the longitudinal direction of the buttonhole (B) by controlling the catching actuator. [4] The hole sewing machine (100) according to claim 3, further comprising: a control device (90) which controls the needle vertical movement mechanism (20), the movement mechanism (270) and the transport mechanism (70) to perform hole sewing around the buttonhole (B) or a predetermined formation position of the buttonhole (B), wherein the setting unit (89) controls the catching actuator to bring the stop position of the thread catching member (85) closer to the same direction as a stitching position of the last needle of the hole sewing at the buttonhole (B) or the predetermined forming position of the buttonhole (B).

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