Sewing machine

Abstract

The invention provides a sewing machine, which can restrain the complexity of the structure of the sewing machine. The sewing machine includes a sewing machine motor; adjusting the motor; the wire cutter is provided with a fixed cutter and a movable cutter; feeding teeth for feeding the cloth forward or backward; a vertical feeding mechanism that reciprocates a feeding tooth in the vertical direction on the basis of a rotational force generated by a sewing machine motor; a horizontal feed mechanism that reciprocates feed teeth in the front-back direction on the basis of a rotational force generated by a sewing machine motor; a wire cutting mechanism that moves the movable cutter on the basis of the rotational force generated by the adjustment motor; and a feed amount adjustment mechanism that changes the feed amount and the feed direction of the feed teeth on the basis of the rotational force generated by the adjustment motor.

Description

Technical Field

[0001] The technology disclosed in this specification relates to a sewing machine. Background Art

[0002] In the technical field of sewing machines, there is known a sewing machine disclosed in Patent Document 1.

[0003] Prior art literature

[0004] Patent Literature

[0005] Patent Document 1: Chinese Patent Application Publication No. 111501222 Summary of the Invention

[0006] (1) Technical issues to be resolved

[0007] A technology is desired for sewing machines that have thread trimming, feed adjustment, and reverse stitching functions to minimize structural complexity. For example, if the thread trimming and reverse stitching functions are implemented using two actuators, while the feed adjustment function is manually implemented, the structure of the sewing machine may become complicated.

[0008] An object of the technology disclosed in this specification is to suppress complication of the structure of a sewing machine.

[0009] (2) Technical solution

[0010] This specification discloses a sewing machine. The sewing machine includes: a sewing machine motor; an adjustment motor; a thread cutter having a fixed cutter and a movable cutter; a feed tooth for feeding fabric forward or backward; a vertical feed mechanism for reciprocating the feed tooth in the vertical direction based on the rotational force generated by the sewing machine motor; a horizontal feed mechanism for reciprocating the feed tooth in the front-back direction based on the rotational force generated by the sewing machine motor; a thread trimming mechanism for moving the movable cutter based on the rotational force generated by the adjustment motor; and a feed amount adjustment mechanism for changing the feed amount and feed direction of the feed tooth based on the rotational force generated by the adjustment motor.

[0011] (3) Beneficial effects

[0012] According to the technology disclosed in this specification, it is possible to suppress complication of the structure of the sewing machine. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 This is a diagram of the sewing machine according to the embodiment as viewed from the rear.

[0014] Figure 2 This is a diagram showing the interior of the sewing machine frame according to the embodiment as viewed from the upper left rear.

[0015] Figure 3This is a diagram showing the interior of the base according to the embodiment as viewed from the upper left rear.

[0016] Figure 4 This is a diagram showing the interior of the base according to the embodiment as viewed from the upper right front.

[0017] Figure 5 This is a diagram showing the interior of the chassis according to the embodiment as viewed from the rear.

[0018] Figure 6 This is a diagram showing the interior of the chassis according to the embodiment as viewed from above.

[0019] Figure 7 This is a diagram showing the interior of the chassis according to the embodiment as viewed from below.

[0020] Figure 8 It is a block diagram showing a sewing machine according to the embodiment.

[0021] Figure 9 This is a diagram of the thread cutter according to the embodiment as viewed from the upper left rear.

[0022] Figure 10 This is a diagram showing the wire cutter according to the embodiment as viewed from above.

[0023] Figure 11 This is a diagram of the thread cutting mechanism according to the embodiment as viewed from the upper left rear.

[0024] Figure 12 This is a diagram of the thread cutting mechanism according to the embodiment as viewed from the upper right front.

[0025] Figure 13 This is a diagram showing the thread cutting mechanism according to the embodiment as viewed from above.

[0026] Figure 14 This is a diagram showing the thread cutting mechanism according to the embodiment as viewed from below.

[0027] Figure 15 This is a diagram of the cloth feeding mechanism according to the embodiment as viewed from the upper left rear.

[0028] Figure 16 This is a diagram of the cloth feeding mechanism according to the embodiment as viewed from the upper right front.

[0029] Figure 17 This is a diagram of the cloth feeding mechanism according to the embodiment as viewed from the right.

[0030] Figure 18 This is a diagram of the cloth feeding mechanism according to the embodiment as viewed from the left.

[0031] Figure 19 This is a diagram showing a portion of the thread cutting mechanism and a portion of the feed amount adjustment mechanism according to the embodiment as viewed from the upper right front.

[0032] Figure 20 This is a diagram showing a portion of the thread cutting mechanism and a portion of the feed amount adjustment mechanism according to the embodiment as viewed from the upper right front.

[0033] Figure 21 This is a diagram showing a portion of the thread cutting mechanism and a portion of the feed amount adjustment mechanism according to the embodiment as viewed from the lower right front.

[0034] Figure 22 It is an exploded perspective view showing a part of the thread cutting mechanism and a part of the feed amount adjustment mechanism according to the embodiment.

[0035] Figure 23 It is a timing chart for explaining the respective operations of the thread cutting mechanism and the feed amount adjustment mechanism according to the embodiment.

[0036] Figure 24 It is a timing chart for explaining the respective operations of the thread cutting mechanism and the feed amount adjustment mechanism according to the embodiment.

[0037] Description of Reference Numerals

[0038] 1…Sewing machine, 2…Sewing machine frame, 2A…Arm, 2B…Base, 2C…Base, 2D…Head, 3…Sewing needle, 4…Needle bar, 5…Feed gear, 6…Thread cutter, 7…Support, 7L…Support, 7R…Support, 8…Sewing machine motor, 9…Adjustment motor, 9A…Output shaft, 10…Needle bar drive mechanism, 11…Cloth feed mechanism, 12…Belt mechanism, 13…Thread trimmer mechanism, 14…Controller, 15…Pedal, 16…Operation panel, 17…Fixed cutter, 17L…Fixed cutter, 17R…Fixed cutter, 18…Movable cutter, 18L…Movable cutter, 18R…Movable cutter, 19…Upper shaft, 20…Converter mechanism, 21…Upper and lower feed shafts, 22…Upper and lower feed shafts Feed mechanism, 23...Horizontal feed shaft, 24...Horizontal feed mechanism, 25...Feed amount adjustment mechanism, 26...Horizontal feed connecting rod, 27...Upper pulley, 28...Lower pulley, 29...Timing belt, 30...Hook, 31...Blade, 32...Cam, 32A...Fixing hole, 32B...Insert hole, 33...Cam groove, 34...Thread trimmer arm, 35...Drive link, 35A...First drive link, 35B...Second drive link, 35C...Slot, 35D...Screw, 36...Right rotation link (first rotation link), 37...Timing link, 37A...First timing link, 37B...Second timing link, 37C...Slot, 37D...Screw, 38...Left rotation link (second rotation link), 39...Right lever, 4 0…Left rod, 41…Right sliding link (first sliding link), 42…Left sliding link (second sliding link), 43…Right movable member (first movable member), 43A…Slider, 43B…Fixed portion, 44…Left movable member (second movable member), 44A…Slider, 44B…Fixed portion, 45…Roller, 46…Shoulder screw, 47…Joint, 48…Joint, 49…Pivot, 50…Joint, 51…Joint, 52…Pivot, 53…Right sliding pin (first sliding pin), 54…Left sliding pin (second sliding pin), 55…Guide groove, 56…Slotted hole, 57…Guide groove, 58…Slotted hole, 59…Feed table, 59A…Holding portion, 59B…Connecting portion, 60…Upper and lower feed eccentric cam Wheel, 61…upper and lower feed connecting rod, 62…horizontal feed arm, 63…horizontal feed eccentric cam, 65…first connecting rod, 65A…first hole, 65B…second hole, 66…adjustment arm, 66A…insertion hole, 66B…insertion hole, 67…feed amount adjuster, 67A…rod, 68…second connecting rod, 69…swing arm, 70…shoulder screw, 71…pin, 72…screw, 90…motor base, AX1…rotating axis, AX2…rotating axis, AX3…rotating axis, AX4…rotating axis, AX5…rotating axis, AX6…rotating axis, AX7…rotating axis, RA…feed amount adjustment range (first rotation range), RB…thread tangent action range (second rotation range), RC…unused range DETAILED DESCRIPTION

[0039] The following describes an embodiment with reference to the accompanying drawings. In the embodiment, an XYZ orthogonal coordinate system is set, and the positional relationship of each part is described with reference to this XYZ orthogonal coordinate system. The direction parallel to the X-axis in a specified plane is set as the X-axis direction. The direction parallel to the Y-axis in a specified plane perpendicular to the X-axis is set as the Y-axis direction. The direction parallel to the Z-axis perpendicular to the specified plane is set as the Z-axis direction. The rotation direction or tilt direction centered on the X-axis is set as the θX direction. The rotation direction or tilt direction centered on the Y-axis is set as the θY direction. The rotation direction or tilt direction centered on the Z-axis is set as the θZ direction.

[0040] In the embodiment, the predetermined plane is parallel to the horizontal plane. The X-axis direction is the front-to-back direction. The Y-axis direction is the left-to-right direction. The Z-axis direction is the up-down direction. The +X direction is the front direction, and the -X direction is the rear direction. The +Y direction is the left direction, and the -Y direction is the right direction. The +Z direction is the upward direction, and the -Z direction is the downward direction. The horizontal direction includes the front-to-back direction and the left-to-right direction.

[0041] [Sewing Machine Overview]

[0042] Figure 1 This is a diagram of a sewing machine 1 according to an embodiment as viewed from the rear. In the embodiment, the sewing machine 1 is an industrial sewing machine. The sewing machine 1 is a double-needle lockstitch sewing machine. Figure 1 As shown, the sewing machine 1 has a sewing machine frame 2 .

[0043] The sewing machine frame 2 includes an arm 2A, a base 2B, a pedestal 2C, and a head 2D. The arm 2A is elongated in the horizontal direction. The base 2B is located below the arm 2A. The base 2B is elongated in the horizontal direction. The base 2B faces the arm 2A. The base 2C connects the right end of the arm 2A to the base 2B. The base 2C is elongated in the vertical direction. The head 2D is located at the left end of the arm 2A. The head 2D protrudes downward from the left end of the arm 2A.

[0044] Figure 2 This is a diagram showing the interior of the sewing machine frame 2 according to the embodiment as viewed from the upper left rear. Figure 3 This is a diagram showing the interior of the chassis 2B according to the embodiment as viewed from the upper left rear. Figure 4 This is a diagram showing the interior of the chassis 2B according to the embodiment as viewed from the upper right front. Figure 5 This is a diagram showing the interior of the chassis 2B according to the embodiment as viewed from the rear. Figure 6 This is a diagram showing the interior of chassis 2B according to the embodiment as viewed from above. Figure 7 This is a diagram showing the interior of a chassis 2B according to the embodiment as viewed from below. Figure 8 It is a block diagram showing the sewing machine 1 according to the embodiment.

[0045] like Figures 1 to 8As shown, the sewing machine 1 has a needle bar 4, a feed tooth 5, a thread cutter 6, a supporting component 7, a sewing machine motor 8, an adjustment motor 9, a needle bar driving mechanism 10, a cloth feeding mechanism 11, a belt mechanism 12, a thread cutting mechanism 13, a controller 14, a pedal 15 and an operation panel 16.

[0046] The needle bar 4 holds the sewing machine needle 3. Two needle bars 4 are provided. The two needle bars 4 are spaced apart in the left-right direction. The needle bar 4 holds the sewing machine needle 3 in such a manner that the sewing machine needle 3 is parallel to the Z axis. The needle bar 4 moves back and forth in the up-down direction. The needle bar 4 is supported by the head 2D. The sewing machine needle 3 has a threading hole for the needle thread to pass through. The sewing machine needle 3 holds the needle thread on the inner surface of the threading hole. As the needle bar 4 moves back and forth in the up-down direction, the sewing machine needle 3 moves back and forth in the up-down direction while holding the needle thread. A needle plate (not shown) is arranged directly below the needle bar 4. The needle plate supports the fabric from below.

[0047] The feed teeth 5 operate in such a manner as to feed the cloth supported on the needle plate forward or backward. The feed teeth 5 are arranged on the lower side of the needle bar 4. The feed teeth 5 are opposite to the needle bar 4. The feed teeth 5 have two tooth portions arranged at intervals in the left-right direction. The feed teeth 5 move according to a prescribed feed trajectory, thereby feeding the cloth forward or backward. The feed teeth 5 are arranged below the needle plate. The feed teeth 5 move in and out of the opening provided in the needle plate by moving according to the feed trajectory. When feeding the cloth, at least a portion of the feed teeth 5 protrudes upward from the upper surface of the needle plate through the opening provided in the needle plate. A kettle (not shown) is arranged below the feed teeth 5. The kettle supplies the lower thread to the cloth. The kettle winds the upper thread around the lower thread.

[0048] The thread cutter 6 cuts the upper and lower threads. It is positioned below the feed teeth 5. It includes a fixed cutter 17 and a movable cutter 18. Two thread cutters 6 are provided. The two thread cutters 6 are spaced apart in the left-right direction. With the upper and lower threads hooked on the movable cutter 18, the movable cutter 18 approaches the fixed cutter 17, cutting the upper and lower threads.

[0049] The support member 7 supports the thread cutter 6. Two support members 7 are arranged in the left-right direction so as to correspond to the two thread cutters 6. The fixed cutter 17 is fixed to the support member 7. The movable cutter 18 is movably supported on the support member 7.

[0050] The sewing machine motor 8 generates a rotational force for operating the needle bar 4, the feed dog 5, and the sewing machine. The sewing machine motor 8 includes a servo motor. The sewing machine motor 8 is supported on the right side of the arm 2A.

[0051] The adjustment motor 9 generates a rotational force for changing the feed amount and feed direction of the feed teeth 5. The adjustment motor 9 also generates a rotational force for operating the thread cutter 6. The adjustment motor 9 includes a pulse motor. The adjustment motor 9 is mounted on the base 2B. The adjustment motor 9 is secured to at least a portion of the base 2B via a motor base 90.

[0052] The feed tooth 5 moves along a prescribed feed trajectory. The feed trajectory is annular. The feed trajectory is elliptical, circular, rectangular, or triangular. The feed amount of the feed tooth 5 refers to the amplitude in the front-to-back direction of the feed tooth 5 moving along the feed trajectory. The feed direction of the feed tooth 5 refers to the rotation direction of the feed tooth 5 moving along the feed trajectory. The feed direction of the feed tooth 5 includes forward feeding, which feeds the fabric forward, and backward feeding, which feeds the fabric backward. Straight sewing (normal sewing) is performed by moving the sewing machine needle 3 back and forth in the vertical direction while feeding the fabric forward. Backstitching is performed by moving the sewing machine needle 3 back and forth in the vertical direction while feeding the fabric backward.

[0053] The needle bar driving mechanism 10 reciprocates the needle bar 4 in the vertical direction based on the rotational force generated by the sewing machine motor 8. The needle bar driving mechanism 10 includes an upper shaft 19 and a conversion mechanism 20.

[0054] The upper shaft 19 is connected to the sewing machine motor 8 via a coupling. The upper shaft 19 is long in the left-right direction. The upper shaft 19 rotates by the rotational force generated by the sewing machine motor 8. The upper shaft 19 rotates in the θY direction around the central axis of the upper shaft 19.

[0055] The conversion mechanism 20 converts the rotation of the upper shaft 19 into reciprocating movement in the vertical direction. The conversion mechanism 20 is located at the left end of the upper shaft 19. The upper end of the needle bar 4 is connected to the conversion mechanism 20. The rotational force of the upper shaft 19 is transmitted to the conversion mechanism 20. Based on the rotational force of the upper shaft 19, the conversion mechanism 20 causes the needle bar 4 to reciprocate in the vertical direction.

[0056] Although not shown, the sewing machine 1 includes a kettle drive mechanism that rotates the kettle based on the rotational force generated by the sewing machine motor 8. The kettle rotates in synchronization with the vertical reciprocating movement of the needle bar 4 to supply bobbin thread to the fabric. The sewing machine 1 sews fabric through the cooperation of the sewing needle 3 held by the needle bar 4 and the kettle.

[0057] The fabric feed mechanism 11 operates the feed teeth 5 based on the rotational force generated by the sewing machine motor 8. The fabric feed mechanism 11 moves the feed teeth 5 in the front-to-back and up-to-down directions in synchronization with the vertical reciprocating movement of the needle bar 4, thereby feeding the fabric forward or backward via the feed teeth 5. The fabric feed mechanism 11 moves the feed teeth 5 along a predetermined feed trajectory.

[0058] The fabric feeding mechanism 11 includes: an upper and lower feeding mechanism 22, a horizontal feeding mechanism 24, and a feed amount adjustment mechanism 25. The upper and lower feeding mechanism 22 causes the feed teeth 5 to reciprocate in the upper and lower directions based on the rotational force generated by the sewing machine motor 8. The upper and lower feeding mechanism 22 includes an upper and lower feeding shaft 21. The horizontal feeding mechanism 24 causes the feed teeth 5 to reciprocate in the front-back direction based on the rotational force generated by the sewing machine motor 8. The horizontal feeding mechanism 24 includes a horizontal feeding shaft 23. The feed amount adjustment mechanism 25 changes the feed amount and feed direction of the feed teeth 5 based on the rotational force generated by the adjustment motor 9. The feed amount adjustment mechanism 25 includes a horizontal feed connecting rod 26. When the feed teeth 5 move based on the rotational force generated by the sewing machine motor 8, the feed trajectory of the feed teeth 5 is changed by changing the feed amount of the feed teeth 5.

[0059] The vertical feed shaft 21 is long in the left-right direction. The vertical feed shaft 21 rotates in the θY direction about the center axis of the vertical feed shaft 21. The horizontal feed shaft 23 is long in the left-right direction. The horizontal feed shaft 23 is positioned behind the vertical feed shaft 21. The vertical feed shaft 21 and the horizontal feed shaft 23 are arranged parallel to each other. The horizontal feed shaft 23 rotates in the θY direction about the center axis of the horizontal feed shaft 23.

[0060] The feed amount adjustment mechanism 25 is disposed between the vertical feed shaft 21 and the horizontal feed shaft 23. The feed amount adjustment mechanism 25 is connected to each of the vertical feed shaft 21 and the horizontal feed shaft 23. The horizontal feed connecting rod 26 is connected to the vertical feed shaft 21. The vertical feed shaft 21 and the horizontal feed shaft 23 are connected via the feed amount adjustment mechanism 25.

[0061] The belt mechanism 12 transmits the rotational force generated by the sewing machine motor 8 to the fabric feed mechanism 11. The belt mechanism 12 transmits the rotational force generated by the sewing machine motor 8 to the upper and lower feed shafts 21. The upper and lower feed shafts 21 rotate based on the rotational force of the sewing machine motor 8 transmitted via the belt mechanism 12. The belt mechanism 12 includes an upper pulley 27 fixed to the right end of the upper shaft 19; a lower pulley 28 fixed to the right end of the upper and lower feed shafts 21; and a timing belt 29 stretched between the upper pulley 27 and the lower pulley 28.

[0062] When the upper shaft 19 is rotated by the rotational force generated by the sewing machine motor 8, the upper pulley 27 rotates together with the upper shaft 19. The rotational force of the upper shaft 19 is transmitted to the upper and lower feed shafts 21 via the upper pulley 27, the timing belt 29, and the lower pulley 28. The upper and lower feed shafts 21 are rotated by the rotational force of the upper shaft 19. The upper and lower feed shafts 21 rotate a full rotation in the θY direction at the same rotational speed as the upper shaft 19.

[0063] The horizontal feed shaft 23 is connected to the vertical feed shaft 21 via a feed adjustment mechanism 25. The rotational force of the vertical feed shaft 21 is transmitted to the horizontal feed shaft 23 via the feed adjustment mechanism 25. The horizontal feed shaft 23 rotates based on the rotational force of the vertical feed shaft 21. When the vertical feed shaft 21 rotates a full circle in the θY direction, the horizontal feed connecting rod 26 reciprocates in the front-to-back direction. The reciprocating movement of the horizontal feed connecting rod 26 causes the horizontal feed shaft 23 to reciprocate in the θY direction.

[0064] The thread cutting mechanism 13 operates the thread cutter 6 based on the rotational force generated by the adjustment motor 9. Operating the thread cutter 6 includes moving the movable cutter 18. The thread cutting mechanism 13 moves the movable cutter 18 based on the rotational force generated by the adjustment motor 9.

[0065] The controller 14 controls the sewing machine motor 8 and the adjustment motor 9. The controller 14 includes a processor such as a CPU (Central Processing Unit), a memory such as a ROM (Read Only Memory) or a RAM (Random Access Memory), and an input / output interface including an input / output circuit capable of inputting and outputting signals and data.

[0066] The pedal 15 is operated by the operator of the sewing machine 1. The operator operates the pedal 15 with his foot. The operation signal generated by operating the pedal 15 is sent to the controller 14. Based on the operation state of the pedal 15, the sewing machine motor 8 is driven or stopped. If the pedal 15 is operated in such a way that the front part of the pedal 15 moves downward, the controller 14 drives the sewing machine motor 8. If the pedal 15 is operated in such a way that the rear part of the pedal 15 moves downward, the controller 14 starts the stop process of the sewing machine 1. The stop process of the sewing machine 1 includes: controlling the sewing machine motor 8 so that the thread cutter 6 is able to cut the upper and lower threads; and controlling the adjustment motor 9 so that the thread cutter 6 is actuated.

[0067] The operation panel 16 includes a flat-panel display and a touch panel. The operation panel 16 is operated by the operator of the sewing machine 1. The operation panel 16 is provided on at least a portion of the sewing machine frame 2. The operator operates the operation panel 16 with his fingers. The operator can operate the operation panel 16 to select the feed amount and feed direction of the feed tooth 5. The operation signal generated by operating the operation panel 16 is sent to the controller 14. By changing the feed amount of the feed tooth 5, the feed trajectory of the feed tooth 5 is changed. The controller 14 controls the adjustment motor 9 so that the feed tooth 5 moves according to the feed amount and feed direction selected by the operation panel 16.

[0068] [Thread tangent mechanism]

[0069] Figure 9 This is a diagram of the thread cutter 6 according to the embodiment as viewed from the upper left rear. Figure 10 This is a diagram showing the wire cutter 6 according to the embodiment as viewed from above. Figure 11 This is a diagram showing the thread cutting mechanism 13 according to the embodiment as viewed from the upper left rear. Figure 12 This is a diagram of the thread cutting mechanism 13 according to the embodiment as viewed from the upper right front. Figure 13 This is a diagram showing the thread cutting mechanism 13 according to the embodiment as viewed from above. Figure 14 This is a diagram showing the thread cutting mechanism 13 according to the embodiment as viewed from below.

[0070] The thread trimming mechanism 13 moves the movable cutter 18 in the front-to-back direction based on the rotational force generated by the adjustment motor 9. A hook 30 and a blade 31 are provided at the front end of the movable cutter 18. After the movable cutter 18 moves so that its blade 31 separates from the fixed cutter 17, the blade 31 of the movable cutter 18 moves closer to the fixed cutter 17, causing the upper and lower threads to be hooked on the hook 30. With the upper and lower threads hooked on the hook 30, the movable cutter 18 moves so that its blade 31 approaches the fixed cutter 17, whereupon the upper and lower threads are cut by the blade 31 of the movable cutter 18 and the fixed cutter 17.

[0071] Two thread cutters 6 are arranged in the left-right direction. Each thread cutter 6 is supported by a support member 7. Two support members 7 are arranged in the left-right direction. The left thread cutter 6 is supported by the left support member 7. The right thread cutter 6 is supported by the right support member 7. In the following description, the support member 7 supporting the left thread cutter 6 is referred to as the support member 7L, and the support member 7 supporting the right thread cutter 6 is referred to as the support member 7R. The fixed cutter 17 of the left thread cutter 6 is referred to as the fixed cutter 17L, and the fixed cutter 17 of the right thread cutter 6 is referred to as the fixed cutter 17R. The movable cutter 18 of the left thread cutter 6 is referred to as the movable cutter 18L, and the movable cutter 18 of the right thread cutter 6 is referred to as the movable cutter 18R.

[0072] The support member 7L is arranged to the left and below the feed teeth 5. The support member 7R is arranged to the right and below the feed teeth 5. The feed teeth 5 are arranged between the support member 7L and the support member 7R in the left-right direction.

[0073] The fixed cutter 17L is fixed to the support member 7L. The fixed cutter 17R is fixed to the support member 7R. The movable cutter 18L is supported by the support member 7L so as to be movable in the front-rear direction. The movable cutter 18R is supported by the support member 7R so as to be movable in the front-rear direction.

[0074] When the movable knife 18L moves forward, the blade 31 of the movable knife 18L separates from the fixed knife 17L. When the movable knife 18L moves backward, the blade 31 of the movable knife 18L approaches the fixed knife 17L. As the movable knife 18L moves backward after moving forward, the upper and lower threads on the left side are hooked on the hook 30 of the movable knife 18L. With the upper and lower threads on the left side hooked on the hook 30 of the movable knife 18L, the movable knife 18L moves backward, and the upper and lower threads on the left side are cut by the blade 31 of the movable knife 18L and the fixed knife 17L.

[0075] When the movable knife 18R moves rearward, the blade 31 of the movable knife 18R separates from the fixed knife 17R. When the movable knife 18R moves forward, the blade 31 of the movable knife 18R approaches the fixed knife 17R. As the movable knife 18R moves forward after moving rearward, the upper and lower threads on the right side are hooked on the hook 30 of the movable knife 18R. With the upper and lower threads on the right side hooked on the hook 30 of the movable knife 18R, the movable knife 18R moves forward, and the upper and lower threads on the right side are cut by the blade 31 of the movable knife 18R and the fixed knife 17R.

[0076] The cam 32 is fixed to the output shaft 9A of the adjustment motor 9. The cam 32 has a cam groove 33. The cam 32 rotates when the output shaft 9A of the adjustment motor 9 rotates. In the embodiment, the output shaft 9A of the adjustment motor 9 protrudes rightward from the stator of the adjustment motor 9.

[0077] The thread trimming mechanism 13 is connected to the cam 32. The thread trimming mechanism 13 includes a roller 45, a thread trimming arm 34, a drive link 35, a right rotation link 36, a synchronization link 37, a left rotation link 38, a right lever 39, a left lever 40, a right sliding link 41, a left sliding link 42, a right movable member 43, and a left movable member 44.

[0078] The roller 45 is arranged in the cam groove 33. The roller 45 moves along the cam groove 33. The thread cutting arm 34 is rotatably supported by the roller 45. The thread cutting arm 34 is connected to the cam 32 via the roller 45.

[0079] The base end of the thread cutting arm 34 is connected to a predetermined portion of the base 2B via a shoulder screw 46. The shoulder screw 46 rotatably supports the thread cutting arm 34. The shoulder screw 46 allows the base end of the thread cutting arm 34 to rotate about a rotation axis AX1 extending through the shoulder screw 46. The rotation axis AX1 is parallel to the Z axis.

[0080] The drive link 35 is rotatably connected to the front end of the thread cutting arm 34. The base end of the drive link 35 is rotatably connected to the front end of the thread cutting arm 34 via a joint 47. The thread cutting arm 34 and the drive link 35 are relatively rotatable about a rotation axis AX2 passing through the joint 47. The rotation axis AX2 is parallel to the Z axis.

[0081] like Figure 14 As shown, the drive link 35 includes a first drive link 35A connected to the front end of the thread cutting arm 34 and a second drive link 35B connected to the first drive link 35A. The second drive link 35B has an elongated hole 35C formed therein. The first drive link 35A and the second drive link 35B are fixed together by two screws 35D inserted into the elongated hole 35C.

[0082] The right rotating link 36 is rotatably connected to the front end of the driving link 35. The base end of the right rotating link 36 is rotatably connected to the front end of the driving link 35 via a joint 48. The driving link 35 and the right rotating link 36 are relatively rotatable about a rotation axis AX3 passing through the joint 48. The rotation axis AX3 is parallel to the Z axis.

[0083] A pivot 49 is provided at the center of the right rotation link 36. The right rotation link 36 rotates in the θZ direction about a rotation axis AX4 passing through the pivot 49. The rotation axis AX4 is parallel to the Z axis.

[0084] The synchronization link 37 is rotatably connected to the front end of the right rotation link 36. The base end of the synchronization link 37 is rotatably connected to the front end of the right rotation link 36 via a joint 50. The right rotation link 36 and the synchronization link 37 are relatively rotatable about a rotation axis AX5 passing through the joint 50. The rotation axis AX5 is parallel to the Z axis.

[0085] like Figure 14 As shown, the synchronization link 37 includes a first synchronization link 37A connected to the front end of the right rotation link 36 and a second synchronization link 37B connected to the first synchronization link 37A. A long hole 37C is formed in the second synchronization link 37B. The first synchronization link 37A and the second synchronization link 37B are fixed by two screws 37D inserted into the long hole 37C.

[0086] The left rotating link 38 is rotatably connected to the front end of the synchronization link 37. The base end of the left rotating link 38 is rotatably connected to the front end of the synchronization link 37 via a joint 51. The synchronization link 37 and the left rotating link 38 are relatively rotatable about a rotation axis AX6 passing through the joint 51. The rotation axis AX6 is parallel to the Z axis.

[0087] A pivot 52 is provided at the center of the left rotation link 38. The left rotation link 38 rotates in the θZ direction around a rotation axis AX7 passing through the pivot 52. The rotation axis AX7 is parallel to the Z axis.

[0088] The right rod 39 extends upward from the right rotating link 36. The lower end of the right rod 39 is fixed to the right rotating link 36. The central axis of the right rod 39 coincides with the rotation axis AX4 of the right rotating link 36. When the right rotating link 36 rotates, the right rod 39 rotates in the θZ direction.

[0089] The left rod 40 extends upward from the left rotation link 38. The lower end of the left rod 40 is fixed to the left rotation link 38. The central axis of the left rod 40 coincides with the rotation axis AX7 of the left rotation link 38. When the left rotation link 38 rotates, the left rod 40 rotates in the θZ direction.

[0090] The right sliding link 41 is connected to the right rotating link 36 via the right rod 39. The base end of the right sliding link 41 is fixed to the upper end of the right rod 39. As the right rod 39 rotates, the front end of the right sliding link 41 pivots partially around the rotation axis AX4. A right sliding pin 53 is provided at the front end of the right sliding link 41. The right sliding pin 53 protrudes downward from the front end of the lower surface of the right sliding link 41.

[0091] The left sliding link 42 is connected to the left pivot link 38 via the left rod 40. The base end of the left sliding link 42 is fixed to the upper end of the left rod 40. As the left rod 40 rotates, the tip end of the left sliding link 42 pivots partially around the pivot axis AX7. A left sliding pin 54 is provided at the tip end of the left sliding link 42. The left sliding pin 54 protrudes downward from the tip end of the lower surface of the left sliding link 42.

[0092] The right movable member 43 is movably supported by the support member 7R. The right movable member 43 supports the movable cutter 18R. The movable cutter 18R is fixed to the right movable member 43. A slider 43A is provided at the bottom of the right movable member 43. A fixing portion 43B is provided at the top of the right movable member 43, to which the movable cutter 18R is fixed. The base end of the movable cutter 18R is fixed to the fixing portion 43B of the right movable member 43 by a screw. A guide groove 55 is provided in the support member 7R. The slider 43A of the right movable member 43 is positioned in the guide groove 55. The guide groove 55 guides the slider 43A in the front-to-back direction. The right movable member 43 has an elongated hole 56 for inserting the right slide pin 53. The elongated hole 56 is provided in the slider 43A. The elongated hole 56 is elongated in the left-right direction.

[0093] The left movable member 44 is movably supported by the support member 7L. The left movable member 44 supports the movable cutter 18L. The movable cutter 18L is fixed to the left movable member 44. A slider 44A is provided at the bottom of the left movable member 44. A fixing portion 44B is provided at the top of the left movable member 44, to which the movable cutter 18L is fixed. The base end of the movable cutter 18L is fixed to the fixing portion 44B of the left movable member 44 by a screw. A guide groove 57 is provided in the support member 7L. The slider 44A of the left movable member 44 is positioned in the guide groove 57. The guide groove 57 guides the slider 44A in the front-to-back direction. The left movable member 44 has an elongated hole 58 for inserting the left slide pin 54. The elongated hole 58 is provided in the slider 44A. The elongated hole 58 is elongated in the left-to-right direction.

[0094] The front end of the movable knife 18R is positioned rearward of the base end of the movable knife 18R. The front end of the movable knife 18R protrudes rearward from the fixed portion 43B of the right movable member 43. The front end of the movable knife 18R is provided with a hook 30 for hooking the upper and lower threads and a blade 31 for cutting the upper and lower threads.

[0095] The front end of the movable knife 18L is positioned forward of the base end of the movable knife 18L. The front end of the movable knife 18L protrudes forward from the fixed portion 43B of the left movable member 44. The front end of the movable knife 18L is provided with a hook 30 for hooking the upper and lower threads and a blade 31 for cutting the upper and lower threads.

[0096] The thread cutting mechanism 13 moves the movable cutter 18 by rotating the driving link 35. Figure 13 As indicated by the solid arrow in FIG3 , if the output shaft 9A of the adjustment motor 9 rotates in the positive direction, the roller 45 moves along the cam groove 33. As the roller 45 moves, the thread trimmer arm 34 rotates in the θZ direction about the shoulder screw 46, causing the tip of the thread trimmer arm 34 to move rightward. The cam groove 33 is shaped so that when the output shaft 9A of the adjustment motor 9 rotates in the positive direction, the tip of the thread trimmer arm 34 moves rightward.

[0097] When the front end of the thread trimmer arm 34 moves rightward, the right rotating link 36, which is connected to the thread trimmer arm 34 via the drive link 35, rotates. The right rotating link 36 rotates so that its base end moves rightward and its front end moves leftward. When the right rotating link 36 rotates so that its front end moves leftward, the left rotating link 38, which is connected to the right rotating link 36 via the synchronization link 37, rotates. The left rotating link 38 rotates so that its base end moves leftward and its front end moves rightward.

[0098] When the right rotation link 36 rotates, the right sliding link 41, which is connected to the right rotation link 36 via the right rod 39, rotates. The right sliding link 41 rotates so that the front end of the right sliding link 41 moves rearward. The right sliding pin 53 of the right sliding link 41 is inserted into the elongated hole 56 of the right movable member 43. When the front end of the right sliding link 41 moves rearward, the movable cutter 18R, supported by the right movable member 43, moves rearward. After the movable cutter 18R moves rearward, it moves forward, and the upper and lower threads on the right side are hooked on the hook portion 30 of the movable cutter 18R.

[0099] When the left rotation link 38 rotates, the left slide link 42, which is connected to the left rotation link 38 via the left rod 40, rotates. The left slide link 42 rotates so that the front end of the left slide link 42 moves forward. The left slide pin 54 of the left slide link 42 is inserted into the elongated hole 58 of the left movable member 44. When the front end of the left slide link 42 moves forward, the movable cutter 18L supported by the left movable member 44 moves forward. After the movable cutter 18L moves forward, it moves backward, and the upper and lower threads on the left side are hooked on the hook portion 30 of the movable cutter 18L.

[0100] like Figure 13 As shown by the dotted arrows, after the upper and lower threads are hooked on the hook 30 of the movable cutter 18R and the upper and lower threads are hooked on the hook 30 of the movable cutter 18L, if the output shaft 9A of the adjustment motor 9 is rotated in the opposite direction, the thread trimming arm 34, the drive link 35, the right rotation link 36, the synchronization link 37, and the left rotation link 38 are rotated, respectively, so that the movable cutter 18R moves forward and the movable cutter 18L moves backward. With the upper and lower threads hooked on the hook 30 of the movable cutter 18R, if the movable cutter 18R moves forward so that the blade 31 of the movable cutter 18R approaches the fixed cutter 17R, the upper and lower threads hooked on the hook 30 of the movable cutter 18R are cut by the blade 31 of the movable cutter 18R and the fixed cutter 17R. In addition, when the upper thread and the lower thread are hooked on the hook portion 30 of the movable cutter 18L, if the movable cutter 18L moves rearward so that the blade 31 of the movable cutter 18L approaches the fixed cutter 17L, the upper thread and the lower thread hooked on the hook portion 30 of the movable cutter 18L are cut by the blade 31 of the movable cutter 18L and the fixed cutter 17L.

[0101] [Cloth feeding mechanism]

[0102] Figure 15 This is a diagram of the cloth feeding mechanism 11 according to the embodiment as viewed from the upper left rear. Figure 16 This is a diagram of the cloth feeding mechanism 11 according to the embodiment as viewed from the upper right front. Figure 17 This is a diagram of the cloth feeding mechanism 11 according to the embodiment as viewed from the right. Figure 18 This is a diagram of the cloth feeding mechanism 11 according to the embodiment as viewed from the left.

[0103] The fabric feeding mechanism 11 includes: a feed table 59, which holds the feed teeth 5; an up and down feed mechanism 22, which causes the feed table 59 to reciprocate in the up and down directions based on the rotational force generated by the sewing machine motor 8; a horizontal feed mechanism 24, which causes the feed table 59 to reciprocate in the front and back directions based on the rotational force generated by the sewing machine motor 8; and a feed amount adjustment mechanism 25, which changes the feed amount and feed direction of the feed teeth 5.

[0104] The feed table 59 includes a holding portion 59A that is elongated in the front-to-back direction, and a connecting portion 59B that extends forward and downward from the lower portion of the holding portion 59A. The feed teeth 5 are held by the holding portion 59A. As the feed table 59 reciprocates in the vertical direction, the two feed teeth 5 reciprocate in the vertical direction. As the feed table 59 reciprocates in the front-to-back direction, the feed teeth 5 reciprocate in the front-to-back direction.

[0105] The vertical feed mechanism 22 includes a vertical feed shaft 21 that rotates based on the rotational force generated by the sewing machine motor 8; a vertical feed eccentric cam 60 that is fixed to the left end of the vertical feed shaft 21; and a vertical feed connecting rod 61 that is attached to the vertical feed eccentric cam 60. The vertical feed connecting rod 61 is connected to the feed table 59.

[0106] The upper and lower feed eccentric cam 60 is held at the base end of the upper and lower feed connecting rod 61. The upper and lower feed connecting rod 61 extends downward from the upper and lower feed eccentric cam 60. The front end of the upper and lower feed connecting rod 61 is connected to the lower end of the connecting portion 59B of the feed table 59. The front end of the upper and lower feed connecting rod 61 and the lower end of the connecting portion 59B are able to rotate relative to each other in the θY direction. If the upper and lower feed shaft 21 rotates a full circle in the θY direction, the upper and lower feed eccentric cam 60 reciprocates in the upper and lower directions with a stroke that is twice the eccentricity of the upper and lower feed eccentric cam 60. As the upper and lower feed eccentric cam 60 reciprocates in the upper and lower directions, the upper and lower feed connecting rod 61 reciprocates in the upper and lower directions. As the upper and lower feed connecting rod 61 reciprocates in the upper and lower directions, the feed table 59 connected to the upper and lower feed connecting rod 61 reciprocates in the upper and lower directions. As the feed table 59 reciprocates in the upper and lower directions, the feed teeth 5 reciprocate in the upper and lower directions.

[0107] The horizontal feed mechanism 24 includes a horizontal feed shaft 23 connected to the vertical feed shaft 21 via a feed amount adjustment mechanism 25 and a horizontal feed arm 62 fixed to the left end of the horizontal feed shaft 23. The horizontal feed arm 62 is connected to the feed table 59.

[0108] The horizontal feed arm 62 extends upward from the horizontal feed shaft 23. The front end of the horizontal feed arm 62 is connected to the rear end of the holding portion 59A of the feed table 59. The front end of the horizontal feed arm 62 and the rear end of the holding portion 59A are relatively rotatable in the θY direction.

[0109] The feed amount adjustment mechanism 25 includes a horizontal feed connecting rod 26 connected to the upper and lower feed shafts 21. The horizontal feed connecting rod 26 is long in the front-to-back direction. A horizontal feed eccentric cam 63 is fixed to the upper and lower feed shafts 21. The front end of the horizontal feed connecting rod 26 is connected to the upper and lower feed shafts 21 via the horizontal feed eccentric cam 63. The front end of the horizontal feed connecting rod 26 rotatably holds the horizontal feed eccentric cam 63.

[0110] If the upper and lower feed shafts 21 rotate a full circle in the θY direction, the horizontal feed connecting rod 26 reciprocates in the front-to-back direction. If the upper and lower feed shafts 21 rotate a full circle in the θY direction, the rear end of the horizontal feed connecting rod 26 reciprocates in the front-to-back direction with a stroke that is twice the eccentricity of the horizontal feed eccentric cam 63. The reciprocating movement of the horizontal feed connecting rod 26 is transmitted to the horizontal feed shaft 23. The horizontal feed shaft 23 reciprocates in the θY direction by the reciprocating movement of the horizontal feed connecting rod 26. The horizontal feed shaft 23 reciprocates in the θY direction, whereby the front end of the horizontal feed arm 62 reciprocates in the front-to-back direction. The front end of the horizontal feed arm 62 reciprocates in the front-to-back direction, whereby the feed table 59 connected to the horizontal feed arm 62 reciprocates in the front-to-back direction. The feed table 59 reciprocates in the front-to-back direction, whereby the feed teeth 5 reciprocate in the front-to-back direction.

[0111] The feed amount adjustment mechanism 25 is connected to the cam 32. The feed amount adjustment mechanism 25 includes a first link 65, an adjustment arm 66, a feed amount adjustment body 67, a horizontal feed connecting rod 26, a second link 68, and a swing arm 69.

[0112] The first link 65 is attached to the right end surface of the cam 32. The first link 65 is connected to the right end surface of the cam 32 via a shoulder screw 70. The shoulder screw 70 rotatably supports the first link 65. The shoulder screw 70 is mounted at a position offset from the central axis of the cam 32. Driven by the adjustment motor 9, the cam 32 rotates in the θY direction about its central axis. The rotation of the cam 32 moves the first link 65.

[0113] The adjustment arm 66 is connected to the first link 65. The adjustment arm 66 is rotatably connected to the first link 65 via a pin 71. The adjustment arm 66 rotates when the cam 32 rotates and the first link 65 rotates.

[0114] The feed amount adjuster 67 is connected to the adjustment arm 66. The adjustment arm 66 is fixed to the left end of the feed amount adjuster 67. The feed amount adjuster 67 is connected to the first link 65 via the adjustment arm 66. When the adjustment arm 66 rotates, the feed amount adjuster 67 and the adjustment arm 66 rotate synchronously.

[0115] The horizontal feed connecting rod 26 is connected to the upper and lower feed shafts 21 and the feed amount adjustment body 67. The front end of the horizontal feed connecting rod 26 is connected to the upper and lower feed shafts 21 via the horizontal feed eccentric cam 63. The rear end of the horizontal feed connecting rod 26 is rotatably connected to the feed amount adjustment body 67. The horizontal feed connecting rod 26 reciprocates in the front-to-back direction as the upper and lower feed shafts 21 rotate a full circle.

[0116] The second link 68 is connected to the feed amount adjusting body 67. The front end portion of the second link 68 is connected to the feed amount adjusting body 67 so as to be rotatable.

[0117] The swing arm 69 is connected to the horizontal feed shaft 23 and the second link 68. The rear end of the second link 68 is rotatably connected to the front end of the swing arm 69. The rear end of the swing arm 69 is fixed to the horizontal feed shaft 23.

[0118] When the horizontal feed connecting rod 26 reciprocates in the front-to-back direction through a full rotation of the vertical feed shaft 21, the rod portion 67A of the feed amount adjuster 67 and the second link 68 each reciprocate in the front-to-back direction. When the second link 68 reciprocates in the front-to-back direction, the swing arm 69 swings. When the swing arm 69 swings, the horizontal feed shaft 23 reciprocates in the θY direction.

[0119] The feed adjustment mechanism 25 changes the feed amount and feed direction of the feed tooth 5 by rotating the feed adjustment body 67. When the adjustment motor 9 is driven and the output shaft 9A rotates, the cam 32 rotates. The rotation of the cam 32 rotates the first connecting rod 65 and the adjustment arm 66. The rotation of the adjustment arm 66 rotates the feed adjustment body 67. Rotating the feed adjustment body 67 changes the relative angle between the feed adjustment body 67 and the second connecting rod 68 in the θY direction. Changing the relative angle between the feed adjustment body 67 and the second connecting rod 68 changes the feed amount and feed direction of the feed tooth 5.

[0120] When the feed amount adjusting body 67 is in a neutral position in the rotational direction of the feed amount adjusting body 67, the swing arm 69 does not swing even if the horizontal feed connecting rod 26 reciprocates in the front-rear direction. Since the swing arm 69 does not swing, the horizontal feed shaft 23 does not reciprocate, and the feed amount of the feed teeth 5 is zero.

[0121] When the feed amount adjusting body 67 is rotated from its neutral position, the swing arm 69 swings in response to the reciprocating movement of the horizontal feed connecting rod 26. The swinging of the swing arm 69 causes the horizontal feed shaft 23 to reciprocate, causing the feed teeth 5 to move in the front-rear direction. The feed amount of the feed teeth 5 is adjusted based on the rotation angle of the feed amount adjusting body 67 from its neutral position. The greater the rotation angle of the feed amount adjusting body 67 from its neutral position, the greater the feed amount of the feed teeth 5.

[0122] When the feed amount adjuster 67 is rotated forward from its neutral position, the feed teeth 5 feed the fabric forward. When the feed amount adjuster 67 is rotated backward from its neutral position, the feed teeth 5 feed the fabric backward. By reciprocating the sewing machine needle 3 in the vertical direction while feeding the fabric forward, straight stitching (normal stitching) is performed. By reciprocating the sewing machine needle 3 in the vertical direction while feeding the fabric backward, reverse stitching is performed.

[0123] When adjusting the feed amount and feed direction of the feed teeth 5 , the controller 14 controls the adjustment motor 9 to rotate the feed amount adjustment body 67 .

[0124] [Relationship between the thread tangent mechanism and the feed adjustment mechanism]

[0125] Figure 19 This is a diagram showing a portion of the thread cutting mechanism 13 and a portion of the feed amount adjusting mechanism 25 according to the embodiment as viewed from the upper right front. Figure 20 This is a diagram showing a portion of the thread cutting mechanism 13 and a portion of the feed amount adjusting mechanism 25 according to the embodiment as viewed from the upper right front. Figure 21 This is a diagram showing a portion of the thread cutting mechanism 13 and a portion of the feed amount adjusting mechanism 25 according to the embodiment as viewed from the lower right front. Figure 22 It is an exploded perspective view showing a part of the thread cutting mechanism 13 and a part of the feed amount adjustment mechanism 25 according to the embodiment. Figure 20 、 Figure 21 as well as Figure 22 Equivalent to Figure 19 Illustrations of the driving link 35 , the horizontal feed connecting rod 26 , the second link 68 , and the swing arm 69 are omitted.

[0126] like Figures 19 to 22 As shown, the thread trimming mechanism 13 and the feed amount adjustment mechanism 25 are connected to the output shaft 9A of the adjustment motor 9. The cam 32 is fixed to the output shaft 9A of the adjustment motor 9. The thread trimming mechanism 13 and the feed amount adjustment mechanism 25 are connected to the output shaft 9A via the cam 32.

[0127] The thread trimming mechanism 13 includes a roller 45 disposed in the cam groove 33 of the cam 32; a thread trimming arm 34 rotatably supported by the roller 45; and a drive link 35 rotatably connected to the front end of the thread trimming arm 34. The feed amount adjustment mechanism 25 includes a first link 65 rotatably connected to the right end surface of the cam 32; an adjustment arm 66 connected to the first link 65; and a feed amount adjustment body 67 connected to the adjustment arm 66. The movable cutter 18 moves by rotating the drive link 35. The feed amount and feed direction of the feed teeth 5 are changed by rotating the feed amount adjustment body 67.

[0128] The horizontal feed connecting rod 26 and the second connecting rod 68 are respectively connected to the rod portion 67A provided on the feed amount adjusting body 67. The rear end of the horizontal feed connecting rod 26 is rotatably connected to the rod portion 67A. The front end of the second connecting rod 68 is rotatably connected to the rod portion 67A.

[0129] The output shaft 9A of the adjustment motor 9 is inserted into a fixing hole 32A provided at the center of the cam 32. The central axis of the output shaft 9A coincides with the rotation axis RX of the adjustment motor 9. The central axis of the cam 32 coincides with the rotation axis RX. The rotation axis RX is parallel to the Y axis.

[0130] The shoulder screw 70 is inserted into the insertion hole 32B of the cam 32 via the first hole 65A provided in the first link 65. The insertion hole 32B is provided at a position offset from the central axis of the cam 32.

[0131] The first link 65 and the adjustment arm 66 are connected via a pin 71. The pin 71 is inserted into the second hole 65B of the first link 65 and the insertion hole 66A of the adjustment arm 66.

[0132] The adjustment arm 66 and the feed amount adjustment body 67 are fixed by two screws 72. The two screws 72 are inserted into two insertion holes 66B provided in the adjustment arm 66 and two threaded holes provided in the left end portion of the feed amount adjustment body 67.

[0133] [Sewing machine movement]

[0134] Figure 23 It is a timing chart for explaining the respective operations of the thread cutting mechanism 13 and the feed amount adjustment mechanism 25 according to the embodiment. Figure 23 The figure shows the relationship between the rotation angle of the output shaft 9A of the adjustment motor 9, the thread cutting mechanism 13, and the feed amount adjustment mechanism 25. The thread cutting mechanism 13 and the feed amount adjustment mechanism 25 are each connected to the output shaft 9A of the adjustment motor 9 via a cam 32. The adjustment motor 9 is used to cut the upper and lower threads, change the feed amount of the feed teeth 5, and change the feed direction of the feed teeth 5.

[0135] exist Figure 23 In the figure, the horizontal axis represents the rotation angle of the output shaft 9A of the adjustment motor 9. The output shaft 9A can rotate between an initial angle of 0° and a maximum angle of 360°. In the following description, the direction of rotation from 0° to 360° is referred to as the forward direction, and the direction of rotation from 360° to 0° is referred to as the reverse direction.

[0136] exist Figure 23 In the figure, the vertical axis represents the feed amount and feed direction of the feed tooth 5. A feed amount of zero means no fabric is being fed, a positive feed amount indicates forward feeding of the fabric, and a negative feed amount indicates backward feeding of the fabric. The feed amount and feed direction of the feed tooth 5 are determined by the rotation angle of the feed amount adjuster 67. The rotation angle of the feed amount adjuster 67 corresponds one-to-one with the feed amount and feed direction of the feed tooth 5. The vertical axis can also be considered the rotation angle of the feed amount adjuster 67. Line Lc represents the relationship between the output shaft 9A and the feed amount and feed direction of the feed tooth 5.

[0137] When the feed amount adjuster 67 is in its neutral position in its rotational direction, the feed amount of the feed teeth 5 is zero. When the feed amount adjuster 67 is rotated forward from its neutral position, the feed teeth 5 move to feed the fabric forward. The feed teeth 5 feed the fabric forward. When the feed amount adjuster 67 is rotated backward from its neutral position, the feed teeth 5 move to feed the fabric backward. The feed teeth 5 feed the fabric backward.

[0138] exist Figure 23 In the figure, the vertical axis represents the position of the movable cutter 18. The position of the movable cutter 18 is determined by the rotation angle of the cam 32. Line Lb represents the relationship between the rotation angle of the output shaft 9A and the position of the movable cutter 18. The initial position of the movable cutter 18 is the position where the blade 31 of the movable cutter 18 is close to the fixed cutter 17. The most advanced position of the movable cutter 18 is the position where the blade 31 of the movable cutter 18 is farthest from the fixed cutter 17. The initial position of the movable cutter 18R is the front end position of the movable cutter 18R's movable range. The most advanced position of the movable cutter 18R is the rear end position of the movable cutter 18R's movable range. The initial position of the movable cutter 18L is the rear end position of the movable cutter 18L's movable range. The most advanced position of the movable cutter 18L is the front end position of the movable cutter 18L's movable range.

[0139] like Figure 23 As shown, when the rotation angle of the output shaft 9A of the adjustment motor 9 is within the feed amount adjustment range RA (first rotation range), which is from 0° to angle α1, the feed amount adjuster 67 rotates to change the feed amount and feed direction of the feed teeth 5. Angle α1 is a value greater than 90° and less than 180°. In the embodiment, angle α1 is approximately 108°.

[0140] When the output shaft 9A rotates at the middle angle αm within the feed adjustment range RA, the feed adjustment body 67 is positioned in a neutral position. When the output shaft 9A rotates at the middle angle αm and the feed adjustment body 67 is positioned in the neutral position, the feed amount of the feed teeth 5 is zero. The middle angle αm is approximately 54°.

[0141] When the output shaft 9A's rotation angle is between 0° and the intermediate angle αm, the feed teeth 5 move to feed the cloth backward. Specifically, when the output shaft 9A's rotation angle is between 0° and the intermediate angle αm, the cloth is fed backward. Rotating the output shaft 9A in the opposite direction from the intermediate angle αm increases the amount of cloth fed backward. When the output shaft 9A's rotation angle reaches 0°, the amount of backward feed reaches its maximum value.

[0142] When the output shaft 9A's rotation angle is between the intermediate angle αm and the angle α1, the feed teeth 5 move to feed the cloth forward. Specifically, when the output shaft 9A's rotation angle is between the intermediate angle αm and the angle α1, the cloth is fed forward. As the output shaft 9A rotates in the positive direction from the intermediate angle αm, the amount of cloth fed forward increases. When the output shaft 9A's rotation angle reaches the angle α1, the forward feed amount reaches its maximum value.

[0143] By moving the sewing machine needle 3 back and forth in the vertical direction while feeding the fabric forward, straight stitching (normal stitching) is performed. By moving the sewing machine needle 3 back and forth in the vertical direction while feeding the fabric backward, reverse stitching is performed. By changing the feed rate of the feed teeth 5, the feed trajectory of the feed teeth 5 is changed. The operator can change the feed rate and feed direction of the feed teeth 5 by operating the operation panel 16. Based on the operation signal generated by operating the operation panel 16, the controller 14 controls the adjustment motor 9 to change the rotation angle of the output shaft 9A within the feed rate adjustment range RA.

[0144] like Figure 23 As shown, when the rotation angle of the output shaft 9A of the adjustment motor 9 is within the cutting operation range RB (second rotation range), which is greater than angle α1 and less than angle α2, the movable cutter 18 moves. Angle α2 is a value greater than α1 and less than 270°. In the embodiment, angle α2 is approximately 188°.

[0145] When the output shaft 9A rotates in the positive direction within the thread cutting operation range RB, the movable knife 18 moves so that the blade 31 of the movable knife 18 separates from the fixed knife 17. Specifically, when the output shaft 9A rotates in the positive direction so that the rotation angle of the output shaft 9A changes from angle α1 to angle α2, the movable knife 18 moves so that the blade 31 of the movable knife 18 separates from the fixed knife 17. After the movable knife 18 moves so that the blade 31 of the movable knife 18 separates from the fixed knife 17, the movable knife 18 then moves so that the blade 31 of the movable knife 18 approaches the fixed knife 17, thereby hooking the upper thread and the lower thread onto the hook portion 30.

[0146] When the output shaft 9A rotates in the reverse direction within the thread cutting operation range RB, the movable cutter 18 moves so that the blade 31 of the movable cutter 18 approaches the fixed cutter 17. That is, when the output shaft 9A rotates in the reverse direction so that the rotation angle of the output shaft 9A changes from angle α2 to angle α1, the movable cutter 18 moves so that the blade 31 of the movable cutter 18 approaches the fixed cutter 17. When the movable cutter 18 moves so that the blade 31 of the movable cutter 18 approaches the fixed cutter 17, the upper thread and the lower thread are cut by the blade 31 of the movable cutter 18 and the fixed cutter 17.

[0147] When the output shaft 9A is rotated in the positive direction from a state where the rotation angle of the output shaft 9A is within the feed amount adjustment range RA, the rotation angle of the output shaft 9A shifts from the feed amount adjustment range RA to the thread cutting operation range RB. The controller 14 controls the sewing machine motor 8 so that the thread cutter 6 can cut the upper and lower threads, and controls the adjustment motor 9 so that the rotation angle of the output shaft 9A shifts from the feed amount adjustment range RA to the thread cutting operation range RB.

[0148] When the operator finishes sewing with the sewing machine 1, the operator operates the pedal 15 so that the rear portion of the pedal 15 moves downward. If the pedal 15 is operated so that the rear portion of the pedal 15 moves downward, the controller 14 starts the stop process of the sewing machine 1. When the pedal 15 is operated so that the rear portion of the pedal 15 moves downward, the controller 14 controls the sewing machine motor 8 so that the thread cutter 6 can cut the upper and lower threads, and controls the adjustment motor 9 so that the rotation angle of the output shaft 9A shifts from the feed amount adjustment range RA to the thread cutting operation range RB. After shifting the rotation angle of the output shaft 9A from the feed amount adjustment range RA to the thread cutting operation range RB, the controller 14 rotates the output shaft 9A in the positive direction within the thread cutting operation range RB. As the output shaft 9A rotates in the positive direction, the movable cutter 18 moves so that the blade 31 of the movable cutter 18 separates from the fixed cutter 17. After the movable cutter 18 moves so that its blade 31 separates from the fixed cutter 17, the output shaft 9A rotates in the reverse direction, causing the movable cutter 18 to move so that its blade 31 approaches the fixed cutter 17, and the upper and lower threads are hooked on the hook portion 30 of the movable cutter 18. After the movable cutter 18 moves so that its blade 31 separates from the fixed cutter 17, the controller 14 rotates the output shaft 9A in the reverse direction within the thread cutting range RB. This reverse rotation of the output shaft 9A causes the movable cutter 18 to move so that its blade 31 approaches the fixed cutter 17, and the upper and lower threads are cut by the blade 31 of the movable cutter 18 and the fixed cutter 17.

[0149] The roller 45 of the thread cutting mechanism 13 is arranged in the cam groove 33 of the cam 32. The shape of the cam groove 33 is determined as follows: Figure 23 As shown, when the rotation angle of the output shaft 9A is within the feed amount adjustment range RA, the thread cutter 6 does not operate.

[0150] like Figure 23 As shown, when the rotation angle of the output shaft 9A is within the thread trimming range RB, the feed amount adjusting body 67 also rotates, changing the feed amount of the feed tooth 5. In the embodiment, when the sewing machine motor 8 is controlled so that the thread cutter 6 can cut the upper and lower threads, the rotation angle of the output shaft 9A shifts from the feed amount adjustment range RA to the thread trimming range RB. When the rotation angle of the output shaft 9A is within the thread trimming range RB, the thread cutter 6 can operate smoothly.

[0151] The range of the rotation angle of the output shaft 9A between the angle α2 and 360° is the non-use range RC in which the feed teeth 5 and the thread cutter 6 do not operate.

[0152] Figure 24It is a timing chart for explaining the respective operations of the thread cutting mechanism 13 and the feed amount adjustment mechanism 25 according to the embodiment. Figure 24 The relationship between the rotation angle of the upper shaft 19, the thread cutting mechanism 13, and the feed amount adjustment mechanism 25 is shown.

[0153] exist Figure 24 In FIG, the horizontal axis represents the rotation angle of the upper shaft 19. The vertical axis represents the feed amount and feed direction of the feed tooth 5 and the position of the movable cutter 18. Figure 24 In FIG. 1 , line Ld represents the relationship between the rotation angle of the upper shaft 19 and the feed amount and feed direction of the feed teeth 5 . Line Le represents the relationship between the rotation angle of the upper shaft 19 and the position of the movable knife 18 .

[0154] Figure 24 The example in which the feed teeth 5 feed the cloth forward at a feed amount of 3 mm during sewing using the sewing machine 1 is shown. The shape of the cam groove 33 is determined so that the thread cutter 6 does not operate during sewing using the sewing machine 1.

[0155] When the operator finishes sewing with the sewing machine 1, he or she operates the pedal 15 so that the rear portion of the pedal 15 moves downward. When the pedal 15 is operated so that the rear portion of the pedal 15 moves downward, the controller 14 starts the stop process of the sewing machine 1. The controller 14 controls the sewing machine motor 8 so that the rotation angle of the upper shaft 19 becomes an angle β1.

[0156] Next, the controller 14 controls the adjustment motor 9 to rotate the output shaft 9A so that the feed amount of the feed tooth 5 becomes the maximum. In addition, the controller 14 controls the sewing machine motor 8 to rotate the upper shaft 19 so that the thread cutter 6 can cut the upper and lower threads. The controller 14 controls the sewing machine motor 8 so that the upper shaft 19 rotates synchronously with the rotation of the output shaft 9A. Figure 24 In the example shown, the rotation angle of the upper shaft 19 when the feed amount of the feed teeth 5 reaches the maximum value is angle β2.

[0157] When the upper shaft 19 is rotated at an angle β2, the thread cutter 6 is in a state where the upper and lower threads can be cut. The state where the thread cutter 6 is in a state where the upper and lower threads can be cut includes a state where the sewing machine needle 3 is separated from the fabric, forming a triangular loop of the upper and lower threads into which the movable cutter 18 can enter.

[0158] After the feed amount of the feed tooth 5 reaches its maximum value and the rotation angle of the upper shaft 19 reaches angle β2, the controller 14 further rotates the output shaft 9A in the positive direction to move the movable cutter 18 from the initial position to the most advanced position. The controller 14 also rotates the upper shaft 19 in synchronization with the rotation of the output shaft 9A. The rotation angle of the upper shaft 19 when the movable cutter 18 is arranged in the initial position is angle β2. The rotation angle of the upper shaft 19 when the movable cutter 18 moves to the most advanced position is angle β3. After the movable cutter 18 moves to the most advanced position, the movable cutter 18 moves to the most retracted position, and the upper thread and the lower thread are hooked on the hook portion 30 of the movable cutter 18.

[0159] After the rotation angle of the upper shaft 19 reaches angle β4, the controller 14 rotates the output shaft 9A in the opposite direction, moving the movable cutter 18 from its most advanced position to its initial position. As the movable cutter 18 moves to its initial position, the upper and lower threads are cut by the blade 31 of the movable cutter 18 and the fixed cutter 17. The rotation angle of the upper shaft 19 when the movable cutter 18 moves to its initial position is angle β5.

[0160] After the movable cutter 18 moves to the initial position and the rotation angle of the upper shaft 19 reaches the angle β5, the controller 14 stops the sewing machine motor 8. In addition, the controller 14 controls the adjustment motor 9 to restore the feed amount of the feed teeth 5 to 3 mm and then stops the adjustment motor 9.

[0161] [Effect]

[0162] As described above, the sewing machine 1 of the embodiment includes: a sewing machine motor 8; an adjustment motor 9; a thread cutter 6, which has a fixed cutter 17 and a movable cutter 18; a feed tooth 5, which feeds the fabric forward or backward; an upper and lower feed mechanism 22, which causes the feed tooth 5 to reciprocate in the upper and lower directions based on the rotational force generated by the sewing machine motor 8; a horizontal feed mechanism 24, which causes the feed tooth 5 to reciprocate in the front and rear directions based on the rotational force generated by the sewing machine motor 8; a thread cutting mechanism 13, which moves the movable cutter 18 based on the rotational force generated by the adjustment motor 9; and a feed amount adjustment mechanism 25, which changes the feed amount and feed direction of the feed tooth 5 based on the rotational force generated by the adjustment motor 9.

[0163] According to the embodiment, the thread trimming mechanism 13 and the feed amount adjustment mechanism 25 are operated by the rotational force generated by a single adjustment motor 9. This can suppress the structural complexity of the sewing machine 1. Furthermore, it can suppress the increase in the number of adjustment motors 9 mounted on the sewing machine 1, thereby suppressing the increase in the size of the sewing machine 1. Furthermore, since it can suppress the increase in the number of adjustment motors 9 mounted on the sewing machine 1, it can suppress the generation of noise from the sewing machine 1. Furthermore, since it can suppress the increase in the number of adjustment motors 9 mounted on the sewing machine 1, it can suppress the power consumption of the sewing machine 1.

[0164] The thread trimming mechanism 13 and the feed amount adjustment mechanism 25 are each connected to the output shaft 9A of the adjustment motor 9. When the output shaft 9A rotates within the feed amount adjustment range RA, the feed amount and feed direction of the feed teeth 5 are changed. When the output shaft 9A rotates within the thread trimming range RB, the movable cutter 18 moves. According to this embodiment, the thread trimming mechanism 13 and the feed amount adjustment mechanism 25 each operate smoothly.

[0165] During the stop process of the sewing machine 1, the output shaft 9A is rotated in the positive direction while the sewing machine motor 8 is controlled so that the thread cutter 6 can cut the upper and lower threads. This causes the rotation angle of the output shaft 9A to shift from the feed amount adjustment range RA to the thread cutting operation range RB. According to the embodiment, the thread cutting mechanism 13 and the feed amount adjustment mechanism 25 each operate smoothly.

[0166] By rotating the output shaft 9A in the positive direction from the middle angle αm within the feed amount adjustment range RA, the forward feed rate of the cloth is increased. By rotating the output shaft 9A in the negative direction from the middle angle αm within the feed amount adjustment range RA, the backward feed rate of the cloth is increased. According to the embodiment, the feed rate and feed direction of the feed teeth 5 can be smoothly changed simply by changing the rotation direction and rotation amount of the output shaft 9A.

[0167] By rotating the output shaft 9A in the positive direction within the thread cutting operation range RB, the movable knife 18 is moved so that the blade 31 of the movable knife 18 is separated from the fixed knife 17. By rotating the output shaft 9A in the negative direction within the thread cutting operation range RB, the movable knife 18 is moved so that the blade 31 of the movable knife 18 is brought closer to the fixed knife 17. According to the embodiment, the thread cutter 6 is operated simply by changing the rotation direction and rotation amount of the output shaft 9A.

[0168] The sewing machine 1 includes a cam 32 fixed to the output shaft 9A of the adjustment motor 9. The thread trimming mechanism 13 and the feed amount adjustment mechanism 25 are connected to the cam 32. According to the embodiment, the thread trimming mechanism 13 and the feed amount adjustment mechanism 25 are smoothly operated by the rotation of the cam 32.

[0169] The cam 32 has a cam groove 33. The thread cutting mechanism 13 includes: a roller 45, which is arranged in the cam groove 33; a thread cutting arm 34, which is rotatably supported by the roller 45; and a driving link 35, which is rotatably connected to the front end of the thread cutting arm 34. The feed amount adjustment mechanism 25 includes: a first link 65, which is rotatably connected to the right end surface of the cam 32; an adjustment arm 66, which is connected to the first link 65; and a feed amount adjustment body 67, which is connected to the adjustment arm 66. The movable cutter 18 moves by rotating the driving link 35. The feed amount and feed direction of the feed tooth 5 are changed by rotating the feed amount adjustment body 67. According to the embodiment, the thread cutting mechanism 13 and the feed amount adjustment mechanism 25 each operate smoothly.

Claims

1. A sewing machine comprising: sewing machine motors; Adjust the motor; a thread cutter having a fixed cutter and a movable cutter; Feed teeth, which feed the fabric forward or backward; a vertical feeding mechanism for reciprocating the feed teeth in the vertical direction based on the rotational force generated by the sewing machine motor; a horizontal feed mechanism that reciprocates the feed teeth in a front-to-rear direction based on a rotational force generated by the sewing machine motor; a thread cutting mechanism that moves the movable cutter based on the rotational force generated by the adjustment motor; and A feed amount adjustment mechanism changes the feed amount and feed direction of the feed teeth based on the rotational force generated by the adjustment motor.

2. The sewing machine according to claim 1, wherein The thread cutting mechanism and the feed amount adjustment mechanism are respectively connected to the output shaft of the adjustment motor. When the rotation angle of the output shaft is in the first rotation range, the feed amount and feed direction of the feed tooth are changed. When the rotation angle of the output shaft is within a second rotation range, the movable cutter moves.

3. The sewing machine according to claim 2, wherein: When the output shaft rotates in the positive direction, the rotation angle of the output shaft shifts from the first rotation range to the second rotation range.

4. The sewing machine according to claim 3, wherein By rotating the output shaft in the positive direction from the middle angle of the first rotation range, the feed amount of the cloth forward is increased. By rotating the output shaft in the reverse direction from the middle angle of the first rotation range, the feed amount of the cloth in the rear direction is increased.

5. The sewing machine according to claim 3, wherein By rotating the output shaft in the positive direction within the second rotation range, the movable cutter moves in such a manner that the blade of the movable cutter separates from the fixed cutter. When the output shaft rotates in the reverse direction within the second rotation range, the movable cutter moves so that the blade of the movable cutter approaches the fixed cutter.

6. The sewing machine according to claim 1, wherein A cam fixed to the output shaft of the adjustment motor, The thread cutting mechanism and the feed amount adjustment mechanism are respectively connected to the cam.

7. The sewing machine according to claim 6, wherein: The cam has a cam groove, The tangent mechanism has: a roller, disposed in the cam groove; a tangent arm rotatably supported on the roller; as well as A driving link rotatably connected to the front end of the thread cutting arm. The feed amount adjustment mechanism has: a first connecting rod rotatably connected to an end surface of the cam; an adjusting arm connected to the first link; and A feed amount adjustment body connected to the adjustment arm, The movable cutter moves by the rotation of the driving link. The feed amount and feed direction of the feed teeth are changed by rotating the feed amount adjuster.

8. The sewing machine according to claim 7, wherein The tangent mechanism has: a first rotating link rotatably connected to a front end portion of the driving link; a first sliding link connected to the first rotating link and having a first sliding pin; as well as a first movable member having a long hole for inserting the first sliding pin; The movable cutter is fixed to the first movable member.

9. The sewing machine according to claim 8, wherein The tangent mechanism has: a synchronous link rotatably connected to a front end portion of the first rotating link; a second rotating link rotatably connected to the front end portion of the synchronization link; a second sliding link connected to the second rotating link and having a second sliding pin; as well as a second movable member having a long hole for inserting the second sliding pin; There are two movable cutters. A movable cutter is fixed to the first movable member, Another movable cutter is fixed to the second movable member.

10. The sewing machine according to claim 7, wherein The upper and lower feeding mechanism has: an upper and lower feed shaft that rotates based on a rotational force generated by the sewing machine motor; an up-and-down feed eccentric cam fixed to the left end portion of the up-and-down feed shaft; and The upper and lower feed connecting rods are mounted on the upper and lower feed eccentric cams and connected to the feed table that holds the feed teeth. The horizontal feeding mechanism has: a horizontal feed shaft connected to the upper and lower feed shafts via the feed amount adjustment mechanism; and A horizontal feed arm is fixed to the left end of the horizontal feed shaft and connected to the feed table. The feed amount adjustment mechanism has: a horizontal feed connecting rod, which is connected to the upper and lower feed shafts and the feed amount adjusting body respectively, and reciprocates in the front-back direction through the full rotation of the upper and lower feed shafts; a second connecting rod rotatably connected to the feed amount adjusting body; as well as A swing arm is connected to the horizontal feed shaft and the second connecting rod respectively.

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