JP2013138700A - Shuttle for sewing machine and sewing machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a shuttle for sewing machine and a sewing machine which can prevent an occurrence of pulling up defectiveness of needle thread with a balance by reducing amount of needle thread passing through the shuttle.SOLUTION: An inner shuttle 4 comprises a first notch 51 in which an edge part 40A is cut at the edge part 40A that is a connection part of a circular bottom surface 40 and a circumference surface 48 of the inner shuttle 4. The first notch 51 comprises a cut part 51A in which an edge part of the circumference surface 48 side is cut and a cut part 51B in which an edge part of the bottom surface 40 side is cut. A position of the first notch 51 is the edge part of the bottom surface 40 corresponding to an end of a lathe 45 which is downstream side with respect to an inner shuttle stopper 41 in a passage direction of the needle thread of the inner shuttle 4 in plane view. The position corresponds to a position to put the needle thread in between the inner shuttle 4 and an outer shuttle. Because the needle thread caught by a point passes this point, a shuttle thread amount that is a length of needle thread to pass through between the outer shuttle and the inner shuttle 4 when the needle thread passes between the inner shuttle stopper 41 and an end abutment of a throat plate can be reduced.

Description

  The present invention relates to a sewing machine hook and a sewing machine, and more particularly to a horizontal hook for a two-needle sewing machine and a sewing machine provided with the horizontal hook.

  Conventionally, there is a sewing machine provided with a pair of left and right horizontal hooks below the needle plate (see, for example, Patent Document 1). In the sewing machine, two sewing needles move up and down in the needle holes of the needle plate to form stitches. Each horizontal hook has an outer hook that rotates clockwise around the axis extending in the vertical direction according to the vertical movement of the sewing needle, and an inner hook that is supported by the outer hook and that can rotate independently of the outer hook. ing. A pair of contact portions project from the lower surface of the needle plate, and the inner hook stop portion of the inner hook comes into contact with the contact portion. The inner hook stopper restrains the inner hook so that the inner hook does not rotate following the outer hook. The sewing machine catches the upper thread that has passed through the cloth with the sewing needle with the sword tip of the outer hook, passes between the outer hook and the inner hook, and entangles the upper thread with the lower thread pulled out from the lower thread hole of the inner hook in the stopped state.

  When the balance of the sewing machine pulls up the upper thread, the upper thread passes through the gap between the inner hook stopper and the contact portion of the throat plate and is released from the horizontal hook, and the entangled lower thread is guided to the cloth to form a stitch. In the horizontal hook, sliding resistance is generated on the upper thread between the inner hook stopper and the contact portion of the needle plate. Due to the sliding resistance, the upper thread does not easily pass through the gap between the inner hook stop portion of the inner hook and the contact portion of the needle plate. The hook device of the sewing machine of Patent Document 1 is provided with tapered inclined surfaces on both side surfaces of the inner hook stopper of the inner hook. The tapered inclined surface reduces the sliding resistance applied to the upper thread between the inner hook stopper and the contact portion of the needle plate.

JP-A-8-299645

  However, even if inclined surfaces are provided on both side surfaces of the inner hook stopper of the inner hook, sliding resistance applied to the upper thread still occurs between the inner hook stopper and the contact portion of the needle plate. The sliding resistance increases the amount of hook thread that is the length of the upper thread that passes between the outer hook and the inner hook when the upper thread passes between the inner hook stopper and the contact portion of the needle plate. End up. As a result, the sewing machine has a problem that a pulling failure occurs when the balance pulls the upper thread.

  An object of the present invention is to provide a sewing machine hook and a sewing machine capable of reducing the amount of the upper thread passing through the hook and preventing the pulling failure of the upper thread by the balance.

  The sewing machine hook according to claim 1 is a sewing machine hook provided with an outer hook supported rotatably and an inner hook supported rotatably relative to the outer hook inside the outer hook. The outer hook is provided with a sword tip for catching an upper thread, and a first notch is provided at a part of the bottom surface of the inner hook through which the upper thread captured by the sword tip passes. The sewing machine hook according to the present invention is provided with the first notch portion on the bottom surface of the inner hook so that the upper hook and the inner hook are moved when the upper thread passes between the inner hook stopper and the contact portion of the needle plate. The amount of the hook thread, which is the length of the upper thread that passes between them, can be reduced, and the upper thread can be prevented from being pulled up poorly when the balance pulls up the upper thread.

  In addition to the structure of the invention of claim 1, the inner hook is provided at the opening side end portion of the outer peripheral surface of the inner hook, and the sewing machine needle plate facing the opening has the sewing hook of the second aspect. An inner hook stopper that prevents the inner hook from rotating together with the outer hook by contacting the contact portion, and an opening-side end portion of the outer peripheral surface of the inner hook, A hook part formed on the downstream side in the passing direction, and a second notch part in which the upper surface of the hook part on the inner hook stopper side is cut out toward the upstream side in the passing direction of the upper thread. Features. The position of the second notch is a position for passing the upper thread captured by the outer hook sword tip between the outer hook and the inner hook. Therefore, the sewing machine hook reduces the amount of hook thread that passes between the outer hook and the inner hook when the upper thread passes between the inner hook stopper and the contact part of the needle plate, and the balance pulls the upper thread up. It is possible to further prevent the pulling failure of the upper thread.

  In addition to the structure of the invention of claim 2, the hook of the sewing machine according to claim 3 is formed by notching the outer side of the opening side end portion of the outer peripheral surface of the inner hook between the inner hook stopper and the flange. A third notch is provided. The position of the third notch is a position around the position where the amount of the upper thread passing between the inner hook and the outer hook becomes the maximum. Therefore, the sewing machine hook reduces the amount of hook thread that passes between the outer hook and the inner hook when the upper thread passes between the inner hook stopper and the contact part of the needle plate, and the balance pulls the upper thread up. It is possible to further prevent the pulling failure of the upper thread.

  In addition to the structure of any one of the first to third aspects, the sewing machine hook according to claim 4 has a race surface between the inner hook and the outer hook formed in the inner hook. Among these, it is provided on the bottom surface of the inner hook corresponding to the position where the upper thread is put between the inner hook and the outer hook. The first notch portion corresponds to the inner hook corresponding to a position where the upper thread is inserted between the inner hook and the outer hook among the race surfaces of the inner hook and the outer hook formed in the inner hook. Since it is provided on the bottom surface, the amount of the upper thread passing between the outer hook and the inner hook can be reduced, and the upper thread pulling failure when the balance pulls the upper thread can be prevented.

  According to a fifth aspect of the sewing machine shuttle, in addition to the structure of any one of the first to fourth aspects of the invention, the inner shuttle is rotated around a shaft portion into which a central hole of the bobbin is inserted and a tip portion of the shaft portion. A L-shaped bobbin presser that is supported in a movable manner and fixes the bobbin to the inner hook; and an outer peripheral surface notch portion that is formed on the outer peripheral surface of the inner hook and into which the tip of the bobbin presser is inserted. And the tip of the bobbin presser is part of the outer peripheral surface of the inner hook. In this case, even in a so-called latch-type inner hook that is directly accommodated in the inner hook and can be pressed by the bobbin presser, the hook thread amount is reduced, and the upper thread pulling failure when the balance pulls the upper thread can be prevented.

  According to a sixth aspect of the sewing machine hook of the present invention, in addition to the structure of the first aspect of the invention, the inner hook is provided with a lid portion that houses a bobbin, and a fourth notch is formed in a part of the lid portion through which the upper thread passes. A feature is provided. In this case, even in a so-called cap-type inner hook in which the bobbin is accommodated in the lid and fitted to the inner hook, the hook thread amount is reduced, and the upper thread pulling failure when the balance pulls the upper thread can be prevented.

  A sewing machine shuttle according to a seventh aspect is characterized in that, in addition to the structure of any one of the first to sixth aspects, a sword tip cutting portion for reducing the thickness of the sword tip is provided on the outer surface of the sword tip. In this case, it is possible to reduce the thickness of the sword tip and reduce the amount of upper thread that the sword tip is hooked by the sword tip cutting portion, and to reduce the amount of upper thread when the upper thread passes between the outer hook and the inner hook. The sewing machine hook can prevent the upper thread from being pulled up poorly when the balance pulls up the upper thread.

  In addition to the structure of any one of claims 1 to 7, the outer hook is provided with a sword that captures the upper thread, and the outer sword from the base to the tip of the sword is provided. The angle with respect to the rotation axis is in the range of 42 degrees to 47 degrees. In this case, by shortening the length of the sword tip, the timing for passing the upper thread hooked by the sword tip between the outer hook and the inner hook can be advanced. Therefore, the hook of the sewing machine can further reduce the pulling failure when the balance pulls up the upper thread after passing between the outer hook and the inner hook.

  The sewing machine according to a ninth aspect may include the sewing machine hook according to any one of the first to eighth aspects. The sewing machine in this case can achieve the effects of the first to eighth aspects.

It is a top view of the horizontal hooks 2 and 12 and the needle plate 1. FIG. 2 is a left side view of a needle plate 1. FIG. 3 is an exploded perspective view of the horizontal hook 2. FIG. It is the perspective view seen from the bottom face side of the inner hook. It is a perspective view of the inner hook. It is another perspective view of the inner hook. It is a top view of the horizontal shuttles 20, 120 and the needle plate 1. FIG. 4 is an exploded perspective view of the horizontal hook 20. It is the perspective view seen from the bottom face side of the inner hook 80. 3 is a perspective view of an inner hook 80. FIG. It is a perspective view of another Example of the inner hook 80. FIG. It is a perspective view of another Example of the inner hook 80. FIG. 3 is a side view of the outer hook 3. FIG. FIG. 14 is a cross-sectional view in the direction of arrows X-X in FIG. 13. It is a figure which shows the length of the sword tip 32. FIG. It is a figure which shows the length of the conventional sword tip 232. FIG. It is the figure equivalent to the conventional FIG.

  DESCRIPTION OF EMBODIMENTS Hereinafter, an embodiment of a sewing machine and a sewing machine hook according to the present invention will be described with reference to the drawings. Hereinafter, the upper side, the lower side, the left side, the right side, the paper surface side, and the paper rear side of FIG. 1 are defined as the rear, front, left, right, upper, and lower sides of the needle plate 1, respectively. With reference to FIG.1 and FIG.2, the horizontal hooks 2 and 12 arrange | positioned at the left and right of the needle plate 1 and the said needle plate 1 are demonstrated. The sewing machine of this embodiment is a two-needle sewing machine having two sewing needles on the left and right. The sewing machine includes horizontal hooks 2 and 12 at symmetrical positions below the left and right sides of a rectangular needle plate 1 in plan view. The needle plate 1 has a pair of left and right cloth feed holes 10 and 11 at the center thereof. The cloth feed holes 10 and 11 include cloth feeds 8 and 18 inside. The cloth feeds 8 and 18 have needle holes 81 and 181 through which sewing needles can be inserted in the vertical direction at substantially the center in the front-rear direction. The cloth feeds 8 and 18 have serrated irregularities on the upper surface. The cloth feeds 8 and 18 slide in the cloth feed holes 10 and 11 in the front-rear direction. The cloth feeds 8 and 18 sandwich the cloth with a cloth presser (not shown) above the needle plate 1 during sewing, and reciprocate in the front-rear direction to feed the cloth.

  As shown in FIG. 1, the needle plate 1 includes an abutting portion 7 on the lower surface of the left end portion, with which an inner hook stopper 41 of the horizontal hook 2 described later comes into contact. The contact portion 7 projects downward from the lower surface of the needle plate 1. The contact portion 7 includes a first contact portion 71 and a second contact portion 72 provided with a certain distance from the first contact portion 71. As shown in FIG. 2, a gap 73 into which the inner hook stopper 41 enters is provided between the first contact portion 71 and the second contact portion 72. The throat plate 1 also has an abutting portion 17 on the lower surface of the right end portion, with which an inner hook stopper 141 of the horizontal hook 12 described later comes into contact. The contact portion 17 has the same structure as the contact portion 7. The contact portion 17 includes a first contact portion 171 and a second contact portion 172.

  Next, with reference to FIG.1 and FIG.3, the detail of the structure of the horizontal hook 2 is demonstrated. Hereinafter, the vertical direction of FIG. Since the structure of the horizontal hook 12 is the same as that of the horizontal hook 2, detailed description thereof is omitted.

  The horizontal hook 2 is located on the lower left side of the needle plate 1. The horizontal hook 2 is a hook that rotates on a horizontal plane. The horizontal hook 2 includes an outer hook 3, an inner hook 4, a hook shaft 34 that is a rotating shaft, and the like. The outer hook 3 rotates clockwise (in FIG. 1). The inner hook 4 is fitted into the outer hook 3 so as to be freely rotatable, and a bobbin 6 around which a lower thread is wound is mounted. The horizontal shuttle 12 is located on the lower right side of the needle plate 1. The horizontal hook 12 includes an outer hook 13 and an inner hook 14. The outer hook 13 rotates clockwise (in FIG. 1). The inner hook 14 is rotatably fitted in the outer hook 13 and is fitted with a bobbin 16 wound with a lower thread.

  The outer hook 3 is fixed to the upper end portion of the hook shaft 34 that rotates in synchronization with the lifting and lowering movement of a sewing needle (not shown). The outer hook 3 includes an inner hook storage portion 31, a race groove 35, a sword tip 32, a hook presser 33 and the like. The inner hook storage portion 31 is a bottomed cylindrical member that stores the inner hook 4. The inner hook storage portion 31 forms a race groove 35 along the inner circumferential direction. The race groove 35 is in contact with a race 45 of the inner hook 4 to be described later, and supports the inner hook 4 to be rotatable. The sword tip 32 protrudes from the outer peripheral portion of the outer hook 3 toward the rotation direction of the outer hook 3. The sword tip 32 captures the loop of the upper thread and rotates the outer periphery of the inner hook 4 to form a seam with the lower thread. The hook presser 33 is provided at the upper end of the outer hook 3 and presses the inner hook 4 from above.

  Next, the structure of the inner hook 4 will be described with reference to FIGS. The inner hook 4 is a rotating body that fits into the inner hook housing portion 31 of the outer hook 3 so as to be rotatable independently of the outer hook 3. The inner hook 4 includes a bobbin storage part 47, an inner hook stopper 41, a bobbin support shaft 43, a bobbin presser 42, a lower thread hole 44, a race 45, an opener contact part 46, a lower thread groove 49, and a bottom surface 40. The inner hook 4 is a so-called latch-type hook that prevents the bobbin from falling off by pressing the bobbin with the bobbin presser 42 from above with the bobbin stored in the bobbin storage portion 47.

  The bobbin storage portion 47 has a bottomed cylindrical shape having an opening that is substantially circular in plan view and opens the bobbin 6 (see FIG. 1) around which a lower thread is wound. The bobbin support shaft 43 is erected at the center of the bobbin storage portion 47 and is inserted into a shaft hole (not shown) of the bobbin 6 to mount the bobbin 6 on the bobbin storage portion 47. The bobbin presser 42 is rotatably provided at the upper end portion of the bobbin support shaft 43. The bobbin presser 42 presses the bobbin from above. A user rotates the bobbin presser 42 horizontally after inserting the bobbin 6 into the bobbin storage portion 47 to prevent the bobbin 6 from falling off. The tip of the bobbin presser 42 enters the outer peripheral surface notch 50 at the upper part of the outer peripheral surface of the inner hook 4 and constitutes a part of the outer peripheral wall.

  The inner hook stopper 41 is a plate-like protrusion that protrudes radially outward from the upper edge of the inner hook 4. The inner hook stopper 41 enters the gap 73 between the first contact portion 71 and the second contact portion 72 of the contact portion 7 (see FIG. 1) of the needle plate 1. Although the inner hook 4 is rotatably fitted to the outer hook 3, a force that rotates in the same direction as the rotation of the outer hook 3 is applied to the inner hook 4 due to the rotation of the outer hook 3. However, the inner hook stopper 41 protruding from the upper end of the outer peripheral surface of the inner hook 4 enters the gap 73 between the first and second contact portions 71 and 72 of the contact portion 7 of the needle plate 1. The inner hook 4 is prevented from rotating by coming into contact with the second contact portion 72.

  The opener contact portion 46 protrudes radially outward from the upper edge of the inner hook 4. The opener contact portion 46 is provided in the counterclockwise direction in plan view of the inner hook stopper 41. The opener contact portion 46 can contact an opener for rotating the inner hook 4 in a direction opposite to the rotation direction of the outer hook 3 to create a gap between the inner hook stopper 41 and the contact portion 7. . In the sewing machine according to the present embodiment, the opener abutting portion 46 is not used because the opener is not provided. The opener contact portion 46 may not be provided.

  The race 45 protrudes along the outer peripheral surface with a constant height and a constant width from the center in the vertical direction of the outer peripheral surface of the inner hook 4 to the lower end side. The inner hook 4 has grooves 481 and 482 formed linearly in the vertical direction at both ends of the opener abutting portion 46 in the radial direction of the inner hook 4. As shown in FIG. 1, the inner hook 14 of the horizontal hook 12 has an inner hook stopper 141, a bobbin support shaft 143, a bobbin presser 142, a lower thread hole (not shown), and a race (not shown). The opener contact portion 146 and the lower thread groove (not shown) are provided to house the bobbin 16 around which the lower thread is wound.

  The lower thread hole 44 is provided at a slightly upper center of the outer peripheral surface 48 of the inner hook 4 in the vertical direction. The lower thread hole 44 penetrates the inner peripheral surface of the inner hook 4. The lower thread hole 44 guides the lower thread pulled out from the bobbin stored in the bobbin storage section 47 to the outside of the inner hook 4. The lower thread groove 49 is a groove formed linearly from the lower thread hole 44 toward the upper edge of the inner hook 4. The lower thread groove 49 guides the lower thread to the lower thread hole 44. The position of the lower thread hole 44 is below the vicinity of the inner hook stopper 41 between the inner hook stopper 41 and the opener contact part 46.

  The user stores the bobbin around which the lower thread is wound in the bobbin storage portion 47 when the bobbin is stored in the inner hook 4. The user pulls out the lower thread from the bobbin and puts it out of the inner hook 4 through the groove 481. The user passes the lower thread taken out of the inner hook 4 between the outer peripheral surface 48 and the leaf spring 56 fixed to the outer peripheral surface 48. The leaf spring 56 applies a predetermined tension to the lower thread. The user passes the lower thread passed between the outer peripheral surface 48 and the leaf spring 56 from the groove 482 to the inside of the inner hook 4. The user passes the lower thread through the lower thread groove 49 and leads out from the lower thread hole 44. The sewing machine can store the bobbin in the inner hook 4.

  As shown in FIG. 4, the bottom surface 40 has a substantially circular shape and is connected to the lower end portion of the outer peripheral surface 48 via the corner portion 40A. The corner portion 40A includes a first cutout portion 51 that is partially cut. The first notch 51 includes a cutting portion 51A obtained by cutting a corner portion on the outer peripheral surface 48 side and a cutting portion 51B obtained by cutting a corner portion on the bottom surface 40 side. The position of the first notch 51 is the bottom surface corresponding to the end of the race 45 on the downstream side of the inner hook stopper 41 in the passing direction of the upper thread of the inner hook 4 (the rotation direction of the outer hook 3) in plan view. 40 corners. This position corresponds to the position (see FIG. 1) where the upper thread is inserted between the inner hook 4 and the outer hook 3. That is, the position of the first notch 51 is a position where the race 45 passes between the outer hook 3 and the inner hook 4 with the upper thread (not shown) captured by the sword tip 32 of the outer hook 3 shown in FIG. . Therefore, the first notch 51 is the length of the upper thread that passes between the outer hook 3 and the inner hook 4 when the upper thread passes between the inner hook stopper 41 and the contact portion 7 of the needle plate. The amount of hook yarn can be reduced. Therefore, the inner hook 4 can prevent the upper thread pulling failure from occurring when the balance pulls the upper thread.

  As shown in FIG. 5, the inner hook 4 includes a flange portion 53 that protrudes outward in the radial direction from the open end of the upper portion of the outer peripheral surface 48. The inner hook 4 has a second notch 54 obtained by cutting the upper surface of the hook 53 on the downstream side of the inner hook stopping portion 41 in the passing direction of the upper thread (the rotation direction of the outer hook 3, the clockwise direction in FIG. 5). Prepare. The second cutout portion 54 is formed by cutting the upper surface of the collar portion 53 obliquely downward toward the upstream side in the upper thread passing direction. The position of the second notch 54 is a position where the race 45 passes between the outer hook 3 and the inner hook 4 with the upper thread captured by the sword tip 32 of the outer hook 3. Therefore, the second cutout portion 54 has a length of the upper thread that passes between the outer hook 3 and the inner hook 4 when the upper thread passes between the inner hook stopper 41 and the contact portion 7 of the needle plate. A certain amount of hook thread can be reduced. Therefore, the inner hook 4 can prevent the upper thread pulling failure from occurring when the balance pulls the upper thread.

  As shown in FIGS. 5 and 6, the inner hook 4 includes a third cutout portion 55 in which the flange portion 53 on the downstream side of the inner hook stopper 41 is cut out radially inward. The third notch 55 is located at the base of the inner hook stopper 41 in the upper thread passage direction (the rotation direction of the outer hook 3, the clockwise direction in FIG. 5). This position is a peripheral position of the position where the amount of the upper thread passing between the inner hook 4 and the outer hook 3 is maximized. The third notch 55 is a hook whose length is the length of the upper thread that passes between the outer hook 3 and the inner hook 4 when the upper thread passes between the inner hook stopper 41 and the contact portion 7 of the needle plate. The amount of yarn can be reduced. Therefore, the inner hook 4 can prevent the upper thread pulling failure from occurring when the balance pulls the upper thread. As shown in FIG. 6, the second cutout portion 54 may not be provided.

  Next, a modified form of the horizontal hooks 2 and 12 will be described. With reference to FIG.7 and FIG.8, the horizontal hooks 20 and 120 arrange | positioned at the right and left of the needle plate 1 and the said needle plate 1 are demonstrated. The sewing machine of the modified form is a two-needle sewing machine as in the above-described embodiment, and the horizontal shuttles 20 and 120 are arranged at symmetrical positions on the left and right of the rectangular needle plate 1 in plan view. The structure of the throat plate 1 and the like other than the horizontal hooks 20 and 120 is the same as that in the above embodiment, and thus description thereof is omitted.

  With reference to FIG.7 and FIG.8, the detail of the structure of the horizontal hook 20 is demonstrated. Hereinafter, the vertical direction of FIG. Since the structure of the horizontal hook 120 is the same as that of the horizontal hook 20, detailed description thereof is omitted.

  The horizontal shuttle 20 is located on the lower left side of the needle plate 1. The horizontal hook 20 is a hook that rotates on a horizontal plane. The horizontal hook 20 includes an outer hook 3, an inner hook 80, a hook shaft 34, and the like. Since the outer hook 3 is the same as that of the said embodiment, detailed description is simplified. The inner hook 80 is fitted into the outer hook 3 so as to be freely rotatable, and a cap 90 fitted with a bobbin (not shown) around which a lower thread is wound is attached. The horizontal shuttle 120 is located on the lower right side of the needle plate 1. The horizontal hook 120 includes an outer hook 13 and an inner hook 180. Since the outer hook 13 is the same as that of the said embodiment, detailed description is abbreviate | omitted. The inner hook 180 is fitted into the outer hook 13 so as to be freely rotatable, and a cap 190 fitted with a bobbin (not shown) around which a lower thread is wound is attached.

  In the outer hook 3, the inner pot accommodating portion 31 is the inside of the bottomed cylindrical shape that accommodates the inner pot 80. The race groove 35 formed in the inner hook storage portion 31 is in contact with the race 88 of the inner hook 80 and supports the inner hook 80 in a rotatable manner. The sword tip 32 of the outer hook 3 captures the loop of the upper thread and forms a seam with the lower thread by turning around the outer periphery of the inner hook 80. A hook presser 33 of the outer hook 3 is provided at the upper end portion of the outer hook 3 and presses the inner hook 80 from above.

  Next, the structure of the inner hook 80 will be described with reference to FIGS. The inner hook 80 is a rotating body that fits in the inner hook housing portion 31 of the outer hook 3 so as to be rotatable independently of the outer hook 3. The inner hook 80 includes a cap 90 that houses a bobbin (not shown) and an inner hook base 82 on which the cap 90 is mounted. The inner hook 80 is a so-called cap-type hook in which a cap 90 containing a bobbin is attached to the inner hook base 82 and the cap 90 is pushed from above by the cap 90 to prevent the bobbin from falling off.

  The inner hook base 82 includes a bobbin storage part 87, a side wall 83, a bobbin support shaft 85, a cap presser 86, an inner hook stopper 84, a race 88, and the like.

  The bobbin storage portion 87 has a substantially circular bottom surface in plan view that opens upward. The bobbin storage portion 87 has a bobbin support shaft 85 erected at the center of the bottom surface. The bobbin support shaft 85 is inserted into a shaft hole of a bobbin (not shown) and a bobbin and a cap 90 are attached. The cap presser 86 is rotatably provided at the upper end portion of the bobbin support shaft 85. The cap presser 86 presses the cap 90 from above. The side wall 83 is erected on the outer peripheral portion of the inner hook base 82. The user, after inserting the cap 90 containing the bobbin into the bobbin housing 87, rotates the cap presser 86 horizontally to prevent the cap 90 from falling off.

  The inner hook stopper 84 is a plate-like protrusion that protrudes radially outward from the upper edge of the side wall 83 of the inner hook 80. The inner hook stopper 84 enters a gap between the first contact portion 71 and the second contact portion 72 of the contact portion 7 of the needle plate 1 shown in FIG. Although the inner hook 80 is rotatably fitted to the outer hook 3, a force that rotates in the same direction as the rotation of the outer hook 3 acts on the inner hook 80 due to the rotation of the outer hook 3. However, the inner hook stopper 84 protruding from the upper end of the outer peripheral surface of the inner hook 80 enters between the first contact portion 71 and the second contact portion 72 of the contact portion 7 of the needle plate 1, Abutting on the second abutting portion 72 prevents the inner hook 80 from rotating. The race 88 protrudes along the outer peripheral surface with a constant height and a constant width from the center in the vertical direction of the outer peripheral portion of the inner hook base 82 to the lower end side.

  The cap 90 is a dome-shaped cap having an opening below. The cap 90 includes an outer peripheral surface 91, a shaft hole 95, an opener contact portion 94, a notch portion 96, a lower thread hole 92, a lower thread groove 93, and a bottom surface 97. The shaft hole 95 is a shaft hole through which the upper end portion of the bobbin support shaft 85 provided at the upper center of the cap 90 passes.

  The opener contact portion 94 protrudes radially outward from the upper edge of the cap 90. The opener abutment portion 94 is located in the counterclockwise direction in plan view of the inner hook stopper 84 of the inner hook 80. The opener abutting portion 94 can abut on an opener for rotating the inner hook 80 in a direction opposite to the rotation direction of the outer hook 3 to create a gap between the inner hook stopper 84 and the abutting portion 7. . In the modified sewing machine, the opener abutment portion 94 is not used because the opener is not provided. The opener contact portion 94 may not be provided. As shown in FIG. 7, the horizontal hook 120 is provided with an inner hook stopper 184, an inner hook 180, a bobbin support shaft 185, a cap presser 186, an opener abutting portion 194, and the like, similar to the horizontal hook 12.

  The notch 96 is notched radially inward at the upper edge of the cap 90. The notch 96 is provided in the clockwise direction in plan view of the opener abutment 94. The notch 96 can be positioned when the bobbin is inserted into the bobbin housing 87 by fitting the upper end of the side wall 83.

  The lower thread hole 92 (see FIG. 11) is provided at the slightly upper center of the outer peripheral surface 91 of the cap 90 in the vertical direction. The lower thread hole 92 penetrates the inner peripheral surface of the cap 90. The lower thread hole 92 guides the lower thread pulled out from the bobbin stored in the cap 90 to the outside of the inner hook 80. The lower thread groove 93 (see FIG. 11) is a groove formed linearly from the lower thread hole 92 toward the lower edge of the cap 90. The lower thread groove 93 guides the lower thread to the lower thread hole 92. The position of the lower thread hole 92 is below the vicinity of the notch 96 between the notch 96 and the opener abutment 94. The shape of the lower thread groove 93 is not limited to a linear shape, and may be formed by extending horizontally from the lower thread hole 92 in parallel with the lower edge of the cap 90 and bending at a right angle in the lower edge direction.

  The user stores the bobbin in the cap 90 when the bobbin around which the lower thread is wound is stored in the inner hook 80. The user pulls out the lower thread from the bobbin and puts it out of the cap 90 through a groove (not shown). The user passes the lower thread that has come out of the cap 90 between the outer peripheral surface 91 and the leaf spring 911 fixed to the outer peripheral surface 91. The leaf spring 911 applies a predetermined tension to the lower thread. The user passes the lower thread passed between the outer peripheral surface 91 and the leaf spring 911 from the groove (not shown) to the inside of the cap 90. The user passes the lower thread through the lower thread groove 93 and guides it from the lower thread hole 92. The user aligns the notches 96 of the cap 90 with the side walls 83 of the inner hook base 82. The user fits the cap 90 into the bobbin storage portion 87. The sewing machine can store the bobbin stored in the cap 90 in the inner pot 80.

  As shown in FIG. 9, the bottom surface 97 has a substantially circular shape, and is connected to the lower end portion of the side wall 83 via the corner portion 97A. The corner portion 97A includes a fourth cutout 89 obtained by cutting a part thereof. The fourth notch portion 89 includes a cutting portion 89A obtained by cutting a corner portion on the side wall 83 side, and a cutting portion 89B obtained by cutting a corner portion on the bottom surface 97 side. The position of the fourth notch 89 is a bottom surface 97 corresponding to the end of the race 88 on the downstream side of the inner hook stopper 84 in the planer view in the upper thread passing direction (rotating direction of the outer hook 3). It is the corner part. This position corresponds to a position (see FIG. 7) where the upper thread is inserted between the inner hook 80 and the outer hook 3. That is, the position of the fourth notch 89 is a position through which the upper thread (not shown) captured by the sword tip 32 of the outer hook 3 shown in FIG. 8 passes. Therefore, the fourth notch 89 has a length of the upper thread that passes between the outer hook 3 and the inner hook 80 when the upper thread passes between the inner hook stopper 84 and the contact portion 7 of the needle plate. A certain amount of hook thread can be reduced. Therefore, the inner hook 80 can prevent the upper thread pulling failure from occurring when the balance pulls the upper thread.

  As shown in FIG. 10, the inner hook 80 has an outer periphery of the upper surface 98 of the cap 90 downstream of the inner hook stopper 84 in the direction in which the upper thread passes (the rotation direction of the outer hook 3, the clockwise direction in FIG. 10). A fifth cutout portion 98A having a side cut is provided. The fifth cutout portion 98A is formed by cutting the upper surface 98 of the cap 90 obliquely downward toward the upstream side in the upper thread passing direction. The fifth notch 98A is a hook whose length is the length of the upper thread that passes between the outer hook 3 and the inner hook 80 when the upper thread passes between the inner hook stopper 84 and the contact portion 7 of the needle plate. The amount of yarn can be reduced. Therefore, the inner hook 80 can prevent the upper thread pulling failure from occurring when the balance pulls the upper thread.

  As shown in FIGS. 10 to 12, the inner hook 80 includes a sixth notch 99 that is obtained by notching the cap 90 on the downstream side of the inner hook stopper 84. The sixth notch 99 is located at the base of the inner hook stopper 84 in the upper thread passage direction (the rotation direction of the outer hook 3, the clockwise direction in FIG. 11). This position is a peripheral position of the position where the amount of the upper thread passing between the inner hook 80 and the outer hook 3 is maximum. The sixth notch 99 is a hook whose length is the length of the upper thread that passes between the outer hook 3 and the inner hook 80 when the upper thread passes between the inner hook stopper 84 and the contact portion 7 of the needle plate. The amount of yarn can be reduced. Therefore, the inner hook 80 can prevent the upper thread pulling failure from occurring when the balance pulls the upper thread. As shown in FIG. 11, the cap 90 may have a hook shape in which a radially outer end portion of the upper surface 98 protrudes. As shown in FIG. 12, the fifth notch 98A on the upper surface 98 of the cap 90 may not be provided.

  Next, the shape of the sword tip 32 will be described with reference to FIGS. As shown in FIGS. 13 and 14, the sword tip 32 is provided with a sword tip cutting part 32 </ b> A and a sword tip cutting part 32 </ b> B that are cut on the outer surface. The sword tip 32 has a shape in which the thickness of the yarn handling portion, which is a portion where the upper thread of the sword tip 232 shown in FIG. In this case, the sword tip 232 can reduce the amount of the upper thread when the upper thread passes between the outer hook 3 and the inner hook 4 after the thread separating portion hooks the upper thread. Therefore, the horizontal hook 2 can prevent the upper thread pulling failure from occurring when the balance pulls the upper thread.

  As shown in FIG. 15, the sword tip 32 of the outer hook 3 is shorter than the conventional sword tip 232 shown in FIG. That is, the sword tip 32 has a small sword radius, which is an angle with respect to the rotation axis of the outer hook 3 from the base portion to the tip portion, which is the root. When the sword radius is small, it is possible to perform the thread division for passing the upper thread hooked by the sword between the outer hook 3 and the inner hook 4 at an early timing. Accordingly, the horizontal hook 2 can reduce the hook thread amount and eliminate the upper thread pulling failure. Specifically, as shown in FIG. 16, the conventional sword tip 232 has a sword tip radius θ1 of about 52 degrees. As shown in FIG. 15, the sword tip 32 is formed with a sword radius θ2 in a range of 42 degrees to 47 degrees. That is, the sword radius θ3, which is the difference between the sword radius θ1 and the sword radius θ2, is 5 to 10 degrees. The sword tip radius θ2 is shorter than the sword tip radius θ1 by the sword tip radius θ3. Therefore, the horizontal hook can perform the thread division for passing the upper thread hooked by the sword tip 32 between the outer hook 3 and the inner hook 4 at an early timing. If the timing of thread separation is advanced, the timing at which the upper thread finishes passing between the outer hook 3 and the inner hook 4 is advanced. Therefore, the horizontal hook can reduce the pulling failure when the balance pulls the upper thread after the thread separation. In this case, when the sword radius θ3 is less than 5 degrees, the timing of thread separation is not much earlier than in the prior art. When the sword radius θ3 is larger than 10 degrees, the trapping of the upper thread of the sword 32 is hindered. Therefore, the sword radius θ3 is preferably 5 degrees to 10 degrees.

  The present invention is not limited to the above embodiment, and various modifications can be made. For example, the inner hook 4 may be provided with all the first notches 51, the second notches 54, and the third notches 55, or may be appropriately combined. Similarly, the inner pot 80 may be provided with all of the fourth cutout portion 89, the fifth cutout portion 98A, and the sixth cutout portion 99, or may be appropriately combined. The outer hook 3 provided with the sword tip 32 whose shape has been changed may be combined with the inner hooks 4 and 80 provided with the respective notches. The outer peripheral surface of the sword tip may be ground into a circular arc shape to reduce the wall thickness.

  In the above embodiment, the sewing machine has an opener for rotating the inner hooks 4, 80 in the direction opposite to the rotation direction of the outer hook 3 to create a gap between the inner hook stoppers 41, 84 and the contact portion 7. Not provided, but may be provided.

DESCRIPTION OF SYMBOLS 1 Needle plate 2 Horizontal hook 3 Outer hook 4 Inner hook 6 Bobbin 7 Contact part 12 Horizontal hook 13 Outer hook 14 Inner hook 16 Bobbin 17 Contact part 20 Horizontal hook 32 Blade tip 32A Blade tip cutting part 32B Blade tip cutting part 34 Lock shaft 40 Bottom 41 Inner hook stopper 42 Bobbin presser 48 Outer peripheral surface 50 Outer peripheral face cutout 51 First cutout 51A Cutting part 51B Cutting part 53 Hook 54 Second cutout 55 Third cutout 80 Inner hook 84 Inner hook stopper 89 Fourth cutout 90 Cap 91 Outer peripheral surface 98A Fifth cutout 99 Sixth cutout 120 Horizontal hook

Claims (9)

In a sewing machine hook comprising an outer hook supported rotatably, and an inner hook supported rotatably relative to the outer hook inside the outer hook,
The outer hook is provided with a sword tip for capturing the upper thread,
A sewing machine hook, wherein a first notch is provided at a part of the bottom surface of the inner hook through which the upper thread captured by the sword tip passes. The inner hook is provided at an opening side end portion of the outer peripheral surface of the inner hook, and comes into contact with a contact portion of a needle plate of a sewing machine facing the opening to prevent the inner hook from rotating together with the outer hook. An inner hook stopper,
At the opening side end of the outer peripheral surface of the inner hook, a collar portion formed on the downstream side in the passing direction of the upper thread from the inner hook stopper,
The sewing machine hook according to claim 1, further comprising: a second cutout portion in which an upper surface of the hook portion on the inner hook stop portion side is cut out toward an upstream side in a passing direction of the upper thread.   3. The sewing machine according to claim 2, further comprising a third cutout portion formed by cutting out an outside of an opening side end portion of an outer peripheral surface of the inner hook between the inner hook stopper and the collar portion. Kettle.   The first notch portion corresponds to the inner hook corresponding to a position where the upper thread is inserted between the inner hook and the outer hook among the race surfaces of the inner hook and the outer hook formed in the inner hook. The sewing machine hook according to any one of claims 1 to 3, wherein the sewing machine hook is provided on a bottom surface of the sewing machine. The inner hook has a shaft portion for inserting a hole in the center of the bobbin;
A bobbin presser having an L-shape in a side view, which is rotatably supported at the tip of the shaft portion and fixes the bobbin to the inner hook;
An outer peripheral surface notch portion that is formed on the outer peripheral surface of the inner hook and into which a tip of the bobbin presser is inserted,
The sewing machine hook according to any one of claims 1 to 4, wherein a tip end portion of the bobbin presser constitutes a part of an outer peripheral surface of the inner hook. The inner hook includes a lid portion for storing a bobbin,
The sewing machine hook according to claim 1, wherein a fourth cutout portion is provided in a part of the lid portion through which the upper thread passes.   The sewing machine hook according to any one of claims 1 to 6, wherein a sword tip cutting portion for reducing a thickness of the sword tip is provided on an outer surface of the sword tip. The outer hook is provided with a sword tip for capturing the upper thread,
The sewing machine hook according to any one of claims 1 to 7, wherein an angle with respect to a rotation axis of the outer hook from a base portion to a tip end portion of the sword tip is in a range of 42 degrees to 47 degrees.   A sewing machine comprising the sewing machine hook according to claim 1.

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