JP4291358B2 - Horizontal half turn bit - Google Patents

Description

  The present invention relates to a horizontal half-rotation rotary hook that can be suitably implemented for extrapolating and sewing a tubular article to be sewn such as a finger insertion part of a glove.

  Sewing apparatuses such as industrial sewing machines and household sewing machines have a sewing machine bed and a substantially L-shaped arm that is mounted on the sewing machine bed and is provided with sewing needles that reciprocate up and down. A rotary shaft that rotates while reversing the rotation direction alternately in one direction and the other direction in conjunction with the operation of the sewing needle is provided in the sewing machine bed. .

  The prior art of the half-rotation rotary hook is described in Patent Document 1, for example. This prior art is a vertical semi-rotary rotary hook whose vertical axis of rotation of the driver and the rotary hook is perpendicular to the moving path of the sewing needle, and the sewing machine bed has one direction around the rotational axis perpendicular to the moving path of the sewing needle. In addition, a rotation shaft that alternately reverses the rotation direction is provided in the other direction, and a vertical full rotation hook is provided on the rotation shaft.

  The vertical full rotation hook is supported by a driver connected to the rotation shaft and the driver so as to be rotatable around the rotation axis, and is alternately pressed by the driver in about 180 ° in one direction and in the other direction to make a half rotation. The bobbin is a bobbin winding body in which the bobbin is wound and the bobbin thread is wound, and a bobbin case in which the bobbin is housed and is detachably attached to the inner hook.

  When the sewing operation is started, the vertical half-turn hook is pressed in one direction and the other direction by a driver interlocking with the half-turn operation of the rotary shaft, and the half-turn action is repeated. These rotary shafts, drivers, and half rotary motions of the rotary hook are synchronized with the vertical movement of the sewing needle, and one stitch is formed on the sewing product for each reciprocation in the one direction and the other direction. The

  The inner rotary hook has a sword that is formed in a tapered shape in the one direction and captures a needle thread inserted through a sewing needle. The needle thread caught by the sword tip slides over the outer surface of the inner hook and the bobbin case by rotating the inner hook in one direction, and makes a round of the bobbin thread pulled out from the bobbin. At this time, the rotation direction of the rotary shaft is reversed in the other direction, and the portion of the sewing needle that is inserted through the sewing product is pulled out from the bottom to the top, so that the needle thread and the bobbin A seam is formed on the workpiece by the thread. Such a seam is also called a main seam, and is a seam that is less prone to fraying than a chain stitch.

Japanese Patent Laid-Open No. 11-290569

  In the prior art, the outer diameter of the half-rotation rotary hook is as large as about 25 mm to 40 mm, and the half-rotation rotary hook is provided in the sewing machine bed. Since the sewing object such as the finger insertion part of the glove cannot be attached in an extrapolated state so as to cover the half-rotation rotary hook, the part corresponding to the fingertip part cannot be sewn in the finger insertion part, There is a problem that it is inferior in productivity.

  In order to solve such problems, it is easy to make the half-turn hook smaller in diameter than the sewing product. However, if the half-turn hook is made smaller in diameter, the driver and the middle hook constituting the half-turn hook It is necessary to reduce the diameter of the bobbin and the bobbin case. When the diameter of the driver, the center rotary hook, the bobbin, and the bobbin case, which are the components of the semi-rotating rotary hook, is reduced, the winding amount of the bobbin thread that can be wound around the bobbin is reduced, and sewing can be performed with one bobbin. The amount of sewing is significantly reduced. If the amount of sewing with one bobbin decreases, the number of bobbin replacements increases, and the sewing work must be frequently interrupted for bobbin replacement, resulting in a decrease in the efficiency of the work to be sewn. There is.

  The object of the present invention is to reduce the number of times the bobbin thread wound body is changed and minimize the interruption of the sewing work as much as possible, and is easy even for a longitudinal cylindrical workpiece such as a finger insertion part of a glove. It is possible to provide a horizontal half-turn hook that can improve the productivity.

The present invention relates to an upper end of a rotary shaft that repeats a half-rotation operation that projects vertically from the machine bed and alternately reverses the rotation direction in one direction and the other direction around the rotation axis parallel to the movement path of the sewing needle through which the needle thread is inserted. A horizontal half-turn hook provided in the section,
A driver connected coaxially to the upper end of the rotating shaft;
A central bite having a sword tip supported by the driver so as to be rotatable about the rotation axis, and rotated alternately by being pushed in the one direction and the other direction by the driver, and capturing the needle thread inserted through the sewing needle. ,
A bobbin thread wound body in which the bobbin thread is wound and accommodated in the inner hook;
Look including a cylindrical casing the driver and the middle bite is rotatably accommodated about the axis of rotation,
The driver has a bottom portion fixed to the rotating shaft and a rotating wall portion that rises from the outer peripheral portion of the bottom portion along the rotating axis, and the bottom portion is directed toward a space in which the inner shell is accommodated. In other words, at least three support pieces having protrusions protruding in the horizontal direction are provided at intervals in the circumferential direction with respect to the rotation axis .

  According to the present invention, the horizontal half-turn hook is provided at the upper end portion of the rotary shaft that protrudes vertically from the sewing machine bed, and the driver is provided coaxially on the rotary shaft. The driver supports the inner rotary hook so as to be rotatable about the rotation axis, and the inner rotary hook accommodates a bobbin thread wound body around which the bobbin thread is wound. The rotation shaft alternately repeats a half-rotation motion that reverses the rotation direction in one direction and the other direction around a rotation axis parallel to the movement path of the sewing needle through which the needle thread is inserted. Such a rotary shaft is driven to rotate half a time in synchronization with the vertical movement of the sewing needle by a rotary drive mechanism provided in a sewing machine bed of a sewing machine such as a home sewing machine or an industrial sewing machine.

  A driver is coupled to the rotating shaft, and the driver is driven to rotate in the same direction by the rotating shaft halfway. The intermediate hook is pressed in the same direction around the rotation axis by the driver, and is driven alternately in the one direction and the other direction following the intermediate hook.

  Such a saddle has a tapered sword tip in one direction, and when the sword rotates in one direction, the sewing needle is lowered from the upper limit position above the horizontal half-turn hook. Then, when reaching the movement path of the sword tip, the sword tip captures the needle thread inserted through the sewing needle, and a needle thread loop is formed on the surface of the center hook by rotating in one direction of the center hook.

  The bobbin thread of the bobbin thread winding body accommodated in the intermediate hook is pulled out from the horizontal half-turn hook, and when the sewing needle starts to move up from the lower limit position, the needle thread captured by the sword tip is While the diameter of the loop is reduced, the yarn passes through the lower end portion of the intermediate hook and passes over the yarn, and is wound around the drawn bobbin yarn.

  When the rotation direction of the rotary shaft is reversed from one direction to the other direction from this state, the inner rotary hook is pressed in the other direction by the driver and starts rotating in the other direction. At this time, the sewing needle changes from the lowering operation to the raising operation. Then, a single seam is formed on the workpiece by the bobbin thread and the needle thread, and a continuous seam is formed on the workpiece by repeating such a sewing operation.

  As the sewing object, it is difficult to sew unless it is extrapolated so as to cover a half-rotation rotary hook such as a finger insertion part or a strap of various gloves such as sports gloves and electric work gloves. An elongate cylindrical sewing thing is mentioned. The bobbin thread wound body may be realized by a wound bobbin obtained by winding a bobbin thread in a coil shape, and is made of a metal having a pair of disk-shaped flanges provided at both ends in the axial direction of a cylindrical winding body. Alternatively, the bobbin thread may be wound around a synthetic resin bobbin.

  The driver and the rotary hook are accommodated in a cylindrical casing so as to be rotatable around the rotation axis. As described above, the driver and the inner rotary hook are accommodated in the casing, so that the rotary hook and the driver rotating to the sewing product do not come into direct contact with each other. Even if there is a horizontal half-rotation hook inserted into one sewing product, that is, with the sewing product extrapolated to the horizontal half-rotation hook, the other half of the sewing product is placed on the other end in the longitudinal direction. One end in the longitudinal direction of the sewing product can be sewn and bonded without damaging the respective sewing products, and the sewing products can be bonded efficiently.

  Further, since the inner rotary hook is rotatably accommodated in the driver, and the bobbin winding body is accommodated in the inner rotary hook, there is no need to use the conventional bobbin case, and the space occupied by the bobbin case can be It can be used to accommodate a spool. Therefore, it is possible to increase the bobbin yarn winding amount that can be wound around the bobbin yarn winding body as compared with the conventional bobbin by increasing the diameter of the bobbin yarn winding body. This reduces the number of times the bobbin thread wound body is replaced due to bobbin thread consumption, compared to the case where a conventional bobbin is used, and reduces the frequency of interrupting the sewing work, thus improving the efficiency of the sewing work. can do.

In addition , since at least three support pieces are provided on the bottom portion of the driver at intervals in the circumferential direction with respect to the rotational axis, in the state in which the driver is accommodated in the driver, the inner hook is rotatable and stable by each support piece. Supported. A needle thread loop is formed when the needle thread is captured by the tip of the center rotary hook, and this needle thread loop passes over the thread while moving along the surface of the center rotary hook.

  In such thread passing, since the needle thread is interposed between each support piece and the bottom of the center hook only when the needle thread passes between each support piece and the center hook, the needle thread is stretched. Although the sliding frictional force acts in the direction and the tension changes, the needle thread passes through the gap between each support piece and the inner rotary hook and the bottom of the driver. The sliding frictional force does not act, thereby preventing the tension of the needle thread from changing greatly, preventing the occurrence of thread balls and thread breakage, and improving the quality of sewing.

  Further, the present invention is characterized in that each protrusion of each support piece is formed to be convexly curved toward a space in which the inner rotary hook is accommodated.

  According to the present invention, each projecting portion of each support piece is formed to be convexly curved toward the space in which the inner pot is accommodated, so that the contact area between each support piece and the inner pot can be reduced, By shortening the time for the needle thread to pass between the support piece and the inner rotary hook, the change in the tension of the needle thread can be reduced, and the occurrence of yarn balls and thread breakage can be more reliably prevented.

  Further, the present invention is characterized in that a thread tension spring for adjusting the tension of the bobbin thread pulled out from the bobbin thread winding body is provided on the intermediate hook.

  According to the present invention, since a thread tension spring is provided in the inner hook, an appropriate tension is applied to the bobbin thread drawn from the bobbin thread winding body to prevent the occurrence of yarn balls and improve the sewing quality. Can do.

  Furthermore, the present invention is characterized in that a braking spring for braking the rotation of the bobbin thread winding body relative to the intermediate hook is interposed between the inner hook and the bobbin thread winding body.

  According to the present invention, it is possible to prevent the bobbin thread winding body housed in the center hook from being idled by the brake spring, and to prevent the occurrence of entanglement and yarn ball due to the relaxation of the bobbin thread. In addition, since the rotation of the bobbin thread winding body is braked by the brake spring, it is possible to suppress a large change in the tension of the bobbin thread and to form a uniform seam.

  According to the present invention, the horizontal semi-rotary rotary hook in which the driver, the intermediate rotary hook, and the bobbin winding body are accommodated in the casing is provided at the upper end portion of the rotary shaft that vertically protrudes from the sewing machine bed. Even a longitudinally sewn product such as a part and a strap can be easily sewn in a state where a horizontal half-turn hook is inserted into the sewn product. In addition, the horizontal half-turn hook has a configuration in which a driver, a middle hook, and a bobbin thread wound body are accommodated in a casing, so the space occupied by the conventional bobbin case is used to accommodate the bobbin thread wound body. The bobbin thread winding amount that can be wound around the bobbin thread winding body can be increased, the number of bobbin thread winding body replacements due to the bobbin thread consumption can be reduced, and the sewing work can be performed. Efficiency can be improved.

Also, the tension of the needle thread passing gap between the bottom of the middle bite and driver changes largely is prevented, thereby preventing the occurrence of the yarn ball and thread breakage, the quality of sewing can be improved.

  Furthermore, according to the present invention, since each protrusion of each support piece is formed to be convexly curved toward the space in which the middle kiln is accommodated, the contact area between each support piece and the middle kiln is reduced, The change in the tension of the needle thread can be reduced, and the occurrence of thread balls and thread breakage can be more reliably prevented.

  Furthermore, according to the present invention, since the thread tension spring is provided on the inner hook, it is possible to prevent the generation of thread balls and improve the sewing quality.

Furthermore, according to the present invention, since the braking spring is interposed between the driver and the inner rotary hook, the bobbin thread is prevented from being entangled and thread balls due to the relaxation of the bobbin thread, and a uniform seam is formed. Sewing quality can be improved.

  FIG. 1 is a cross-sectional view of a part of a sewing apparatus 2 including a horizontal half-rotation rotary hook 1 according to an embodiment of the present invention. In the present embodiment, description will be made assuming a finger insertion part of a glove as a longitudinal cylindrical sewing product that is sewn by the horizontal half-rotating rotary hook 1. The horizontal half rotary hook 1 is mounted on the upper end portion of the rotary shaft 4 that vertically protrudes upward (upward in FIG. 1) from the sewing machine bed 3 of the sewing device 2.

  Such a horizontal half-turn hook 1 includes a driver 5 that is detachably fixed to the rotary shaft 4, a middle hook 6 that is housed in the driver 5, and a bobbin that is a bobbin thread winding body that is housed in the middle hook 6. 7 and a right cylindrical casing 8 in which the driver 5 and the rotary hook 6 are accommodated.

  The rotation shaft 4 is rotated halfway in the directions of arrows A1 and A2 by alternately reversing the rotation direction about every 180 ° around the rotation axis L2 parallel to the movement path L1 of the sewing needle 13. The inner rotary hook 6 is pressed by the driver 5 that is coaxially connected to the rotary shaft 6 and rotates in the same direction A1, A2. Such a half-rotation operation of the rotary shaft 4, the driver 5 and the rotary hook 6 is synchronized with the reciprocating movement of the sewing needle 13 up and down.

  A glove having a plurality (5 in the present embodiment) of finger insertion portions is made of cloth, and the fingertip portion opened by each finger insertion portion in a state where the horizontal half-rotation rotary hook 1 of the present embodiment is inserted into each finger insertion portion. Reinforcement sheets made of occlusion and artificial leather or other fabric are sewn.

  When the glove that is the sewing object is an adult golf glove, the outer diameter D1 of the casing 8 is selected to be, for example, 15 mm as an outer diameter that can be easily inserted into each finger insertion portion of the glove. Further, the inner diameter D2 of the casing 8 is selected to be, for example, 13 mm in order to secure an accommodation space capable of accommodating the driver 5, the inner rotary hook 6 and the bobbin 7, and to ensure a required mechanical strength.

  In the present embodiment, the glove is described as an example of a golf glove for adults. However, the glove is not limited thereto, and may be other sports gloves such as a baseball glove. Gloves may be used.

  An upper end portion of a sleeve 10 through which the rotary shaft 4 is inserted is integrally connected to a lower end portion of the casing 8, and a lid 11 is provided at the upper end portion of the casing 8 so as to be freely opened and closed. The lid body 11 is connected to an upper end portion of an arm (not shown) whose lower end portion is fixed to a flange portion 28 of a bracket 26 described later. The arm is made of thin plate-shaped spring steel, and can be angularly displaced over a closed position where the lid 11 covers the opening of the casing 8 and an open position where the opening of the casing 8 is opened. When the lid 11 is in the closed position, the arms are substantially parallel along the outer peripheral surface of the sleeve 10, and when opening the casing 8 for exchanging the bobbin 7 or the like, Grips the lid 11 with fingers and moves it from the closed position to the open position against the spring force of the arm, whereby the upper end is angularly displaced in a direction away from the casing 8. When the operator releases his / her hand from the lid 11 in the open position, the arm is restored by its own elastic recovery force in a direction in which the upper end of the arm approaches the casing 8, and the opening of the casing 8 is blocked by the lid 11. Can be returned to the closed position.

  In the state where the opening of the casing 8 is closed at the closed position, the lid 11 is covered so that the driver 5, the inner hook 6 and the bobbin 7 and the like housed in the casing 8 face upward and are not exposed. The vicinity of the sewing position of the object can be supported on the casing 8. A cover body 12 is constituted by the casing 8, the sleeve 10 and the lid body 11.

  Such a cover body 12 covers the driver 5, the inner hook 6 and the rotating shaft 4 so that rotating members such as the driver 5, the inner hook 6 and the rotating shaft 4 are not directly exposed to the outside. Is prevented from coming into contact with the rotating driver 5 and the inner rotary hook 6 and the like.

  The rotary shaft 4 is inserted into a shaft hole 16 formed in the horizontal upper plate 15 of the sewing machine bed 3, and has a right columnar shaft portion 17 extending above and below the upper plate 15 and an upper end of the shaft portion 17. And a mounting portion 18 fixed coaxially to the portion. The shaft portion 17 and the attachment portion 18 are made of, for example, a structural steel material. The attachment portion 18 is formed with a right cylindrical fitting hole 19 opened upward, and a screw hole 20 penetrating in one radial direction from the outer peripheral surface to the inner peripheral surface facing the fitting hole 19. The base shaft 21 of the driver 5 is inserted into the fitting hole 19, and the outer peripheral surface is pressed by the distal end portion of the lock bolt 22 screwed into the screw hole 20 to be prevented from coming off. When the lock bolt 22 is screwed out, the distal end portion of the lock bolt 22 is separated from the base shaft 21, and the driver 5 can be removed from the mounting portion 18 of the rotating shaft 4. In this state, the driver 5 is detachably attached to the rotating shaft 4.

  The sleeve 10 has two upper and lower bearing portions 23 and 24 that support the rotating shaft 4, and a connecting portion 25 that extends between the bearing portions 23 and 24. The lower end portion of the casing 8 is connected to the upper end portion of the one bearing portion 23, and the upper end portion of the connecting portion 25 is connected to the lower end portion of the one bearing portion 23. Further, the lower end portion of the connecting portion 25 is connected to the upper end portion of the other bearing portion 24. The casing 8, the one bearing portion 23, the connecting portion 25, and the other bearing portion 24 form the same axis, and are formed by integrally connecting right cylindrical bodies having different inner diameters in the axial direction.

  Such a sleeve 10 is arranged vertically on the upper plate 15 of the sewing machine bed 3 while being positioned coaxially with the shaft hole 16, and the lower surface of the other bearing portion 24 is supported by the upper surface of the upper plate 15. . When the rotary shaft 4 is inserted into the sleeve 10, the inner peripheral surface of the connecting portion 25 is spaced radially outward from the outer peripheral surface of the rotary shaft 4. The inner peripheral surfaces of the bearing portions 23 and 24 are in contact with the outer peripheral surface of the rotary shaft 4 and pivotally supported so that the rotary shaft 4 can be smoothly rotated around the rotation axis L2. Each of the bearing portions 23 and 24 is structurally realized by a sliding bearing and functionally realized by a radial bearing.

  A lower end portion of the sleeve 10 is vertically held on the upper plate 15 by the sewing machine bed 3 by a bracket 26. The lower end portion of the sleeve 10 includes a part of the other bearing portion 24 and the coupling portion 25 and is configured to hold the sleeve 10 with respect to the upper plate 15 with high strength.

  The bracket 26 includes a cylindrical part 27 having a cylindrical shape in which a region on the lower end side including a part of the other bearing part 24 and the connecting part 25 of the sleeve 10 is inserted, and the sewing machine bed 3 of the cylindrical part 27. And a flange portion 28 extending radially outward from a lower end portion disposed on the upper portion. The flange portion 28 is fixed to the upper plate 15 of the sewing machine bed 3 by a plurality of bolts 29, and the upper plate 15 of the sewing machine bed 3 has a high strength so that the sleeve 10 is not undesirably displaced with respect to the shaft hole 16. keeping. Since the sleeve 10 that holds the rotary shaft 4 is attached to the upper plate 15 of the sewing machine bed 3 by the bracket 26 in this way, even if an external force acts on the sleeve 10 due to contact of an object or the like, the upper plate 15 of the sewing machine bed 3. The perpendicularity to the upper surface of the rotating shaft 4 is maintained, and the occurrence of problems such as the rotational axis L2 of the rotating shaft 4 being displaced from the axial line of the shaft hole 16 is prevented.

  In this way, the lower end portion of the rotary shaft 4 standing on the sewing machine bed 3 is inserted through the shaft hole 16 from the upper plate 15 of the sewing machine bed 3 and protrudes downward. 30 and 31 are pivotally supported on the lower surface of the upper plate 15 so as to be rotatable about the rotation axis L2. Each of the bearings 30 and 31 is realized by a radial bearing, prevents the rotation shaft 4 from falling off from the sleeve 10, and allows rotation about the rotation axis L2.

  The protruding length H from the upper surface of the sewing machine bed 3 to the upper surface of the lid body 11 is selected from 150 mm to 200 mm, and the lid body 11 is inserted to the vicinity of the tip of the finger insertion portion of the glove that is the sewing object. In this state, the entire glove is gently attached between the lid 11 and the sewing machine bed 3 and is set to an optimum protruding length that can be sewn while smoothly moving the sewing position near the finger insertion portion. .

  A pulley 32 is coaxially mounted and fixed to a portion of the rotary shaft 4 between the bearings 30 and 31. An endless timing belt 33 is wound around the pulley 32, and the driving force is applied to the timing belt 33 such that the traveling direction is alternately reversed in the directions of arrows B1 and B2.

  The drive means 34 includes an electric motor, a speed reducer, and a rotation direction conversion means, and reduces the rotation of the output shaft of the electric motor in one direction by the speed reducer, and rotates the reduced rotation in one direction. It is converted into a reciprocating rotational motion in which the rotational direction is reversed in the direction of the arrows B1 and B2 by the direction converting means. The rotation direction conversion means transmits the rotation in one direction of the output shaft of the speed reducer to the pinion as a reciprocating rotation motion in which the rotation direction is alternately reversed by a crank mechanism. The reciprocating rotation motion of the pinion is transmitted to the timing belt 33. It is comprised so that it may transmit to the rotating shaft of the other pulley wound. The rotation axis of the other pulley is parallel to the rotation axis L2 of the one pulley 32, and the timing belt 33 is wound around and stretched between the pulleys.

  The reciprocating movement of the timing belt 33 driven by the driving means 34 in the directions of arrows B1 and B2 is transmitted to the rotary shaft 4 through the one pulley 32, and the rotary shaft 4 is rotated around the rotary axis L2. The rotation direction is alternately reversed in the directions of the arrows A1 and A2 every about 180 ° and is rotated halfway. The rotation of the output shaft of the speed reducer of the driving means 34 is also transmitted to a needle bar of a sewing machine arm provided on the sewing machine bed 3 by a rotation transmission mechanism including a plurality of gears and a rotary shaft. The sewing needle 13 attached to the lower end of the bar is reciprocated up and down in synchronization with the rotating shaft 4.

  As described above, the driver 5 is connected to the rotary shaft 4 that is driven to rotate half-way, and the rotary hook 6 is attached to the driver 5. The intermediate hook 6 is alternately pressed by the driver 5 in the direction of the arrow A1 and the direction of the arrow A2, and makes a half-rotation motion in the same direction. The intermediate hook 6 has a sword tip 37 that tapers in one rotational direction A 2, and the needle thread inserted through the sewing needle 13 is captured by the sword tip 37. The needle thread captured by the sword tip 37 forms a needle thread loop along the surface of the intermediate hook 6 by the rotation of the intermediate hook 6 in one direction A2, and slides on the surface while expanding the needle thread loop.

  When the inner rotary hook 6 further rotates in one rotational direction A2, the needle thread loop slides on the surface of the intermediate rotary hook 6 while being caught by the sword 37, passes over the bobbin, and is pulled out from the bobbin 7. At the annular sewing position where the longitudinal one end C1 of one sewing product C mounted on the sleeve 10 and the other longitudinal end E1 of the other sewing product portion E are engaged with the thread and overlapped with each other. A seam is formed. Such a seam is formed over the entire circumference in the sewing position where the longitudinal one end C1 of the one sewing product C and the longitudinal other end E1 of the other sewing product E are overlapped, In this way, the workpieces C and E are connected to each other, and the fingertip portion of the glove finger insertion portion that is open is sewn.

  FIG. 2 is a plan view of the horizontal half-turn hook 1, FIG. 3 is a cross-sectional view of the horizontal half-turn hook 1 as viewed from section line III-III in FIG. 2, and FIG. 4 is a section line IV in FIG. It is an expanded sectional view of the horizontal half rotation hook 1 seen from -IV. In FIG. 2, the lid 11 is omitted for easy illustration. The driver 5 is coaxially connected to the mounting portion 18 of the rotating shaft 4 and is unidirectionally around the rotating axis L2 in synchronization with the reciprocating operation of the sewing needle 13 through which the needle thread is inserted by the rotating shaft 4. The half rotation operation is repeated alternately in A1 and the other direction A2.

  The inner rotary hook 6 is rotatably supported around the rotation axis L2 by the driver 5, and is alternately pressed in the one direction A1 and the other direction A2 by one circumferential end and the other circumferential end of the driver 5. Then, it follows the driver 5 and makes a half-rotation motion. The intermediate hook 6 also has a sword tip 37 that captures the needle thread inserted through the sewing needle 13 as described above. The sword tip 37 is tapered toward the other direction A2 that is one of the rotational directions, and is disposed at a position spaced about 0.1 mm radially inward from the inner peripheral surface of the casing 8, and contacts the casing 8. It is possible to rotate along the inner peripheral surface of the casing 8 without doing so. The bobbin 7 around which the bobbin thread 40 is wound is accommodated in such an inner rotary hook 6.

  A U-shaped notch 41 opened upward is formed at the upper end of the casing 8 so that the lowered sewing needle 13 does not contact the casing 8. The notch 41 has a depth F that can avoid interference with the sewing needle 13 that has reached the lower limit position in parallel with the rotation axis L2 from the end face 42 of the upper end portion of the casing 8, and in the circumferential direction. It has a width G that can allow displacement in the direction intersecting the movement path L1 such as the deflection of the needle tip of the sewing needle 13. The depth F is selected to be 6 mm, for example, and the width G is selected to be 3 mm, for example.

  5 is a plan view of the driver 5, FIG. 6 is a side view of the driver 5 seen from above in FIG. 5, and FIG. 7 is a side view of the driver 5 seen from below in FIG. The driver 5 rises along the rotation axis L2 from the outer periphery of the base shaft 21 connected to the rotation shaft 4, the disc-shaped bottom portion 43 to which the base shaft 21 is fixed, and the rotation axis L2. And a rotary wall portion 44 having a half-moon-like cross section.

  At the bottom 43, at least three support pieces 46a, 46b, and 46c each having protrusions 45a, 45b, and 45c projecting from the upper surface 43a toward the space in which the inner shuttle 6 is accommodated are arranged with respect to the rotation axis L2. Provided at intervals in the direction. Each of the support pieces 46a, 46b, and 46c includes protrusions 45a, 45b, and 45c, and right cylindrical shaft portions 47a, 47b, and 47c on which the protrusions 45a, 45b, and 45c are integrally formed.

  Each of the protrusions 45a, 45b, 45c has an outer surface that is convexly curved toward the space in which the inner hook 6 is accommodated. The convexly curved outer surface may be, for example, a hemispherical surface or a part of a spherical surface, may be conical, or may be a part of a spheroid. As described above, the outer surface of each protrusion 45a, 45b, 45c is represented by various shapes such as a hemisphere, a part of a spherical surface, a conical shape, and a part of a spheroid as described above. The cross section perpendicular to L2 has a reduced shape.

  The arrangement relationship of these support pieces 46a, 46b, 46c will be described. Each of the shaft portions 47a, 47b, 47c has a right cylindrical shape and is press-fitted into shaft holes 48a, 48b, 48c formed in the bottom portion 43, respectively, and only the projections 45a, 45b, 45c are formed from the upper surface of the bottom portion 43. Projects upward. The first support piece 46a is disposed farthest away from the rotary wall 44 with a radius R1 on the opposite side of the rotary wall 44 with respect to the rotation axis L2. The radius R1 is selected to be 4 mm, for example.

  The second support piece 46b is arranged at an angular position of an angle θ1 = 105 ° downstream of one rotation direction A1 with respect to the first support piece 46a with a radius R2 from the rotation axis L2. The radius R2 is selected to be 3 mm, for example. The third support piece 46c is arranged at an angular position of an angle θ2 = 105 ° downstream of the other rotation direction A2 with respect to the first support piece 46a with a radius R3 from the rotation axis L2. The radius R3 is selected to be 3 mm, for example.

  The vertices of the protrusions 45a to 45c exist on a virtual plane perpendicular to the rotation axis L2, and the bottom surface of the inner rotary hook 6 is stabilized, and the sliding resistance due to friction is reduced as much as possible to freely rotate. Can be supported. Further, the protrusions 45a to 45c of the support pieces 46a to 46c are formed so as to be convexly convex toward the accommodation space of the inner rotary hook 6, that is, on the front side perpendicular to the paper surface of FIG. Furthermore, when the needle thread loop passes over the outer surface of the inner rotary hook 6, the contact area between the bottom surface of the intermediate hook 6 and each of the protrusions 45 a to 45 c is small. The time required to pass between the bottom surface of the rotary hook 6 and each of the protrusions 45a to 45c can be remarkably shortened, thereby reducing the change in the tension of the needle thread when passing over the yarn, thereby reducing the occurrence of thread breakage and yarn balls. Therefore, it is possible to continuously form seams with appropriate thread tightening, and the sewing quality is improved.

  Further, since each of the protrusions 45a, 45b, and 45c has a curved shape that protrudes upward, the needle thread is guided smoothly between the bottom surface of the inner rotary hook 6 and the top of each of the protrusions 45a, 45b, and 45c. It is possible to pass through the yarn, to prevent the occurrence of slack in the needle yarn loop, the yarn ball and the yarn breakage, and to improve the stability of the yarn passing operation.

  FIG. 8 is a plan view of the intermediate hook 6, FIG. 9 is a side view of the intermediate hook 6 viewed from the arrow IX of FIG. 8, and FIG. 10 is a side view of the intermediate hook 6 viewed from the arrow X of FIG. FIG. FIG. 11 is a cross-sectional view of the intermediate hook 6 as viewed from the cutting plane line XI-XI in FIG. 8, and FIG. 12 is a cross-sectional view of the central rotary 6 as viewed from the cutting plane line XII-XII in FIG. For convenience of explanation, a central axis L3 parallel to the rotation axis L2, an X plane including the central axis L3, and a Y plane including the central axis L3 and orthogonal to the X plane are assumed, and FIG. The configuration of the rotary hook 6 will be described.

  The intermediate hook 6 is connected to a straight cylindrical peripheral wall 50 having a central axis L3, a bottom plate 51 that is connected to one end of the peripheral wall 50 in the axial direction, and a cylindrical stud 52 that is erected on the bottom plate 51. And a bobbin holding means 53 attached to the stud 52.

  The peripheral wall 50 includes a thin semi-cylindrical portion 54, a first contact portion 55, a sword tip portion 56, a fitting portion 57, a thread take-out portion 58, and a second contact portion 59. The semi-cylindrical portion 54 forms a part of a small-diameter cylindrical body whose radius r1 to the outer peripheral surface is about 4.5 mm, for example, and is formed over an angular range of about 180 ° with respect to the central axis L3. A first abutting portion 55 is formed at one end in the circumferential direction of the semi-cylindrical portion 54, and a second abutting portion 59 is formed at the other end in the circumferential direction of the semi-cylindrical portion 54. Is done.

  The first contact portion 55 has a concave contact surface 60 that opens toward the downstream side in the other rotational direction A2, and the sword tip portion is radially outward from the region where the contact surface 60 is formed. 56 is integrally formed. The fitting portion 57 is continuously formed on the upstream side of the first contact portion 55 in the rotational direction A2, and the yarn take-out portion 58 is continuous on the upstream side of the fitting portion 57 in the rotational direction A2. Further, the second contact portion 59 is formed continuously on the upstream side in the rotational direction A2 of the yarn take-out portion 58.

  The second contact portion 59 has a contact surface 62 inclined from the X plane toward the downstream side in the rotational direction A2 toward the outer side in the radial direction with respect to the central axis L3. An angle θ3 formed by the contact surface 62 and the X plane is selected from 2 ° to 10 °, for example. The fitting portion 57 is formed on the downstream side in the rotational direction A1 from the X plane in a state where the tip portion of the sword tip portion 56, that is, the sword tip 37 is in contact with the X plane. As shown in FIG. 12, the fitting portion 57 includes a fitting recess 71 into which a free end portion of an operation lever 70 to be described later is fitted, and between the fitting recess 71 and the outer peripheral surface of the fitting portion 57. A thread guide hole 72 that communicates is formed.

  FIG. 13 is a cross-sectional view of the vicinity of the yarn take-out portion 58 of the inner rotary hook 6 and shows a cross section as viewed from the cutting plane line XIII-XIII in FIG. A thread guide groove 73 for guiding the bobbin thread 40 wound around the bobbin 7 to the thread guide hole 72 of the fitting part 57 is formed in the thread take-out part 58 of the intermediate hook 6. A communication groove 74 is formed in the outer peripheral portion of the intermediate hook 6 over the fitting portion 57 and the yarn take-out portion 58, and the yarn guide groove 73 and the yarn guide hole 72 are communicated with each other by the communication groove 74. The bobbin yarn 40 wound around is guided from the yarn guide groove 73 of the yarn take-out portion 58 through the communication groove 74 to the fitting recess 71 from the yarn guide hole 72 of the fitting portion 57.

  The yarn guide groove 73 is formed on the peripheral wall 50 of the inner rotary hook 6 from a portion downstream of the second contact portion 59 in the rotational direction A2 to a portion upstream of the sword tip 56 in the rotational direction A2. 6 is opened outward in the radial direction. A thread tension spring 95 is provided in such a thread guide groove 73. The end of the thread tension spring 95 on the upstream side in the rotational direction A2 is fixed to the peripheral wall 50 by a countersunk screw bolt 96. The end of the thread tension spring 95 on the downstream side in the rotational direction A2 reaches the thread guide hole 72, and the bobbin thread 40 is threaded between the thread guide hole 72 and the thread take-out part 58 by the thread tension spring 95. 73 is pressed on the bottom surface. A shaft portion of the countersunk screw bolt 96 is inserted into the thread tension spring 73 and a long hole 97 extending in the longitudinal direction of the thread tension spring 73 is formed. A tightening position by the countersunk screw bolt 96 along the long hole 97 is formed. By adjusting the tension, the pressing force applied to the bobbin thread 40 pressed by the thread tension spring 73 on the bottom surface of the thread guide surface 73 is changed, the tension of the bobbin thread 40 is optimally adjusted, and the quality of the sewing is improved. Can be improved.

  14 is a side view of the operation lever 70, FIG. 15 is a plan view of the operation lever 70, and FIG. 16 is a side view of the operation lever 70 as viewed from the left in FIG. Referring also to FIG. 4, the bobbin holding means 53 includes an operation lever 70, a pin 80 that connects the operation lever 70 to the free end portion of the stud 52 so as to be angularly displaceable in the directions of arrows K 1 and K 2, and the stud 52. It has a compression coil spring 81 accommodated therein and a spring receiving piece 82 attached to one end of the compression coil spring 81.

  The operation lever 70 is connected to the base portion 84 in which the pin hole 83 through which the pin 80 is inserted, and the base portion 84, and changes in a direction in which the distance r2 from the axis of the pin 80 decreases as the operation direction K2 becomes downstream. A cam portion 86 having a cam surface 85 formed thereon, and an operation portion 87 which is connected to the base portion 84 and extends on the opposite side of the cam portion 86 with respect to a virtual plane including the axis of the pin 80.

  The operation portion 87 is formed with a guide groove 88 for guiding the bobbin thread 40 pulled out from the bobbin 7 accommodated in the inner shuttle 6 to the outside, and a guide hole 89 penetrating the operation portion 87 in the thickness direction. Is done. The guide groove 88 is opened on one surface side facing the accommodation space of the inner hook 6 of the operation portion 87 in a state where the operation portion 87 is tilted and the free end portion is fitted in the fitting recess 71. The yarn guide hole 72 communicates with the vicinity of the end. The yarn guide hole 72 is opened on the other surface of the operation portion 87 from a region near the base end portion of the guide groove 88.

  Since the guide groove 88 and the guide hole 72 are formed in the operation portion 87 as described above, the bobbin thread 40 wound around the bobbin 7 attached to the inner rotary hook 6 is pulled out from the outermost periphery, and the intermediate rotary hook 6 It can be taken out from the vicinity of the center where there is little change in tension due to the rotation of.

  According to the present embodiment, the inner hook 6 is accommodated in the driver 5 provided coaxially with the rotating shaft 4, and the bobbin 7 around which the bobbin thread 40 is wound is accommodated in the inner hook 6. The rotation shaft 4 is a rotation operation that alternately repeats a half-rotation motion of about 180 ° in one direction A1 and the other direction A2 around a rotation axis L2 parallel to the movement path L1 of the sewing needle 13 through which the needle thread is inserted. To do.

  When the rotary shaft 4 is alternately rotated around the rotational axis L2 in one direction A1 and the other direction A2, the driver 5 connected to the rotary shaft 4 is rotationally driven in the same direction, and the middle hook 6 is driven in the same direction by the driver 5. It is pressed and rotates alternately in the one direction A1 and the other direction A2. The intermediate hook 6 has a sword tip 37, and the needle thread inserted through the sewing needle 13 is captured by the sword tip 37 when the intermediate hook 6 rotates in one direction A <b> 1.

  The bobbin thread 40 of the bobbin 7 accommodated in the intermediate hook 6 is pulled out and stretched to a needle drop hole of the sewing machine bed 3, for example, and the sewing needle 13 moves in a direction away from the intermediate hook 6, thereby The needle thread loop of the needle thread expanded in a loop shape along the surface of the thread 6 passes over the thread and is wound around the bobbin thread 40 stretched from the bobbin 7 to the needle drop hole. The needle thread is pulled up by raising a balance (not shown) provided in the sewing machine, for example, by the bobbin thread 40 and the needle thread. A seam is formed.

  The bobbin 7 may be realized by a wound bobbin obtained by winding the bobbin thread 40 in a coil shape. As shown in the cross-sectional view of FIG. It may be made of metal or synthetic resin on which the disc-shaped flanges 92 and 93 are provided.

  18 is a plan view showing the braking spring 100, and FIG. 19 is a side view of the braking spring 100 as seen from below in FIG. Referring also to FIG. 4, a braking spring 100 that brakes the rotation of the bobbin 7 relative to the intermediate hook 6 is interposed between the intermediate hook 6 and the bobbin 7. The brake spring 100 is a substantially C-shaped plate spring in which the end faces 101a and 101b of the circumferential end portions 100a and 100b are spaced apart from each other with a distance ΔL in the circumferential direction, and a hardened steel having a thickness t of 0.1 mm. And inclined at a distance ΔH in the axial direction from one circumferential end 100a to the other circumferential end 100b. The distance ΔH is selected to be 0.5 mm, for example, and the axial spring force can be changed according to the distance ΔL.

  When the bobbin 7 tries to rotate by tension when the bobbin thread 40 is unwound by such a brake spring 100, the bobbin 7 accommodated in the inner hook is prevented from slipping and tangled due to the relaxation of the bobbin thread 40. Generation and yarn ball generation can be prevented. Further, since the idling of the bobbin 7 is prevented by the brake spring 100, a large change in the tension of the bobbin thread 40 is suppressed, and a uniform seam can be formed.

  Since the driver 5 and the rotary hook 6 are accommodated in the cylindrical casing 8 so as to be rotatable around the rotation axis L2, there are joints at intermediate portions between both longitudinal ends of the longitudinal cylindrical sewing product. Even if it exists, the rotary hook 6 and the driver 5 that rotate to the sewing product are not in direct contact, and the half-rotating rotary hook 1 can be sewn while being inserted into the sewing product.

  In addition, since the internal shuttle 6 is rotatably accommodated in the driver 5 and the bobbin 7 is accommodated in the internal shuttle 6, the space occupied by the conventional bobbin case inside the internal shuttle 6 can be used as a bobbin. 7 can be used to accommodate.

  Therefore, the winding amount of the bobbin yarn 40 that can be wound around the bobbin 7 is increased compared to the winding amount of the conventional bobbin yarn, and the number of replacements of the bobbin 7 due to the consumption of the bobbin yarn is reduced. The efficiency of the sewing work can be improved.

  Further, according to the present embodiment, at least three support pieces 45a to 45c are provided on the bottom portion 43 of the driver 5 at intervals in the circumferential direction with respect to the rotation axis L2, so that the intermediate hook 6 is accommodated in the driver 5 Then, the intermediate hook 6 is rotatably and stably supported by the support pieces 45a to 45c. At the time of passing over the thread, only when the needle thread passes between the protrusions 46 of the support pieces 45a to 45c and the inner hook 6, the support pieces 45a to 45c and the bottom of the intermediate hook 6 are in contact with each other. Because the sliding frictional force acts on the needle thread in the tension direction and the tension changes, the needle thread is not interposed between the support pieces 45a to 45c and the intermediate hook 6 because the needle thread is interposed between them. Since it passes through the gap between the inner rotary hook 6 and the bottom of the driver 5, a large sliding frictional force does not act on the needle thread, thereby preventing the tension of the needle thread from changing greatly. The occurrence of thread breakage is prevented and the quality of sewing is improved.

  Further, according to the present embodiment, each protrusion of each of the support pieces 45a to 45c is formed to be convexly curved toward the space in which the intermediate hook 6 is accommodated. The contact area with the rotary hook 6 is small, the time for the needle thread to pass between the support pieces 45a to 45c and the intermediate rotary hook 6 is shortened, the change in the tension of the needle thread is reduced, and the thread ball and thread breakage. Can be more reliably prevented.

  In another embodiment of the present invention, the article to be sewn may be a longitudinal cylindrical object such as a strap, in addition to the above-described finger insertion part of the glove.

It is sectional drawing which shows the horizontal half rotation rotary hook 1 of one Embodiment of this invention. FIG. 2 is a plan view of a horizontal half-turn hook 1. FIG. 3 is a cross-sectional view of the horizontal semi-rotary rotary hook 1 as viewed from the section line III-III in FIG. 2. FIG. 4 is an enlarged cross-sectional view of a horizontal semi-rotary rotary hook 1 as viewed from a cutting plane line IV-IV in FIG. 2. 4 is a plan view of a driver 5. FIG. FIG. 6 is a side view of the driver 5 as viewed from above in FIG. 5. It is the side view seen from the lower part of FIG. FIG. 6 is a plan view of the intermediate hook 6. FIG. 9 is a side view of the intermediate hook 6 as viewed from above in FIG. 8. FIG. 9 is a side view of the intermediate hook 6 as viewed from below in FIG. 8. FIG. 9 is a cross-sectional view of the intermediate hook 6 as viewed from a cutting plane line XI-XI in FIG. 8. FIG. 9 is a cross-sectional view of the intermediate hook 6 as viewed from a cutting plane line XII-XII in FIG. 8. FIG. 9 is a cross-sectional view of the intermediate hook 6 as viewed from a cutting plane line XIII-XIII in FIG. 8. 3 is a side view of an operation lever 70. FIG. 3 is a plan view of an operation lever 70. FIG. It is a side view of the operation lever 70 seen from the left side of FIG. It is sectional drawing of the bobbin 7. FIG. 2 is a plan view showing a braking spring 100. FIG. FIG. 19 is a side view of the braking spring 100 as viewed from below in FIG. 18.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Horizontal half rotation hook 2 Sewing apparatus 3 Sewing machine bed 4 Rotating shaft 5 Driver 6 Medium hook 7 Bobbin 8 Casing 10 Sleeve 11 Lid body 12 Cover body 13 Sewing needle 15 Upper plate 16 Shaft hole 17 Shaft part 18 Mounting part 19 Fitting hole 20 Screw hole 21 Base shaft of driver 5 22 Fixing bolt 23, 24 Bearing portion 25 Connection portion 26 Bracket 27 Tube portion 28 Flange 29 Bolt 30, 31 Thrust bearing 32 Pulley 33 Timing belt 34 Drive means 37 Blade tip 40 Bobbin thread 41 Notch A1 , A2 Rotation direction B1, B2 Timing belt 33 travel direction D1 Cover body 12 outer diameter D2 Casing 8 inner diameter L1 Movement path L2 Rotation axis

Claims (4)

It is provided at the upper end of the rotating shaft that projects vertically from the sewing machine bed and repeats a half-rotation operation that alternately reverses the rotation direction in one direction and the other direction around the rotation axis parallel to the movement path of the sewing needle through which the needle thread is inserted. A horizontal half turn
A driver connected coaxially to the upper end of the rotating shaft;
A central bite having a sword tip supported by the driver so as to be rotatable about the rotation axis, and rotated alternately by being pushed in the one direction and the other direction by the driver, and capturing the needle thread inserted through the sewing needle. ,
A bobbin thread wound body in which the bobbin thread is wound and accommodated in the inner hook;
Look including a cylindrical casing the driver and the middle bite is rotatably accommodated about the axis of rotation,
The driver has a bottom portion fixed to the rotating shaft and a rotating wall portion that rises from the outer peripheral portion of the bottom portion along the rotating axis, and the bottom portion is directed toward a space in which the inner shell is accommodated. A horizontal half-rotation rotary hook characterized in that at least three support pieces having protruding protrusions are provided at intervals in the circumferential direction with respect to the rotation axis . Wherein the projections of each support piece, the horizontal half rotary kiln according to claim 1, characterized in that it is curved in a convex toward the space in which the in kettle is accommodated. The horizontal half-turn hook according to claim 1 or 2 , wherein a thread tension spring for adjusting the tension of the bobbin thread drawn out from the bobbin thread winding body is provided in the intermediate hook. Between the in bite and the bobbin thread winding body according to any one of claims 1 to 3 for damping spring for braking the rotation of the bobbin thread winding body is characterized in that it is interposed with respect to the middle bitten Horizontal half-turn bitten.

Images