Multi-functional small cylinder differential computerized lockstitch machine

Abstract

The application discloses a multi-functional small cylinder differential computerized flat sewing machine, which comprises a machine head, a bottom plate component, a feeding tooth, a tooth rack seat, an up-down transmission mechanism, a transverse transmission mechanism, a driving mechanism and a thread shearing mechanism. The up-down transmission mechanism comprises a pair of tooth lifting shafts which are rotatably installed on the bottom plate component and driven; the transverse transmission mechanism comprises a feeding transmission shaft which is rotatably installed on the bottom plate component and reciprocatingly rotates. The up-down transmission mechanism and the transverse transmission mechanism are matched to drive the feeding tooth to continuously generate a feeding action. The length of the small mouth can be adjusted according to the position of the sewing machine needle as a base point and the length of the tooth lifting shaft and the feeding transmission shaft, so that the overall length and volume of the sewing machine can be adapted. The transmission structure of the tooth lifting shaft, the feeding transmission shaft, the feeding shaft and the crank connecting shaft in combination with the connecting rod and the crank, and the thread shearing transmission shaft are no longer limited by the length of the transmission distance. The corresponding length can be set according to the requirement to meet the length requirement of the small mouth.

Description

Technical Field

[0001] This invention relates to a feed dog drive mechanism for a sewing machine. Background Technology

[0002] Existing cylindrical differential computerized flatbed sewing machines require a sleeve. The size of the sleeve's outer diameter depends on the sewing process and the fabric diameter. For example, when sewing cylindrical items such as trouser legs and cuffs, the sleeve needs to be as small as possible to meet usage requirements. Simultaneously, because the sleeve needs to house the feeding mechanism and thread trimming mechanism, space constraints place stringent requirements on the dimensions of these mechanisms. It has been found that existing feeding mechanisms on the market, due to factors such as manufacturing processes, wear, and component strength, cause the lower feed dog to deform under pressure when the presser foot and upper feed dog are lowered, resulting in the lower feed dog being at or slightly above the needle plate's surface. This leads to poor or extremely poor feeding. Summary of the Invention

[0003] To address the problems existing in the use of the prior art, this invention provides a feed tooth drive mechanism that can effectively increase the length of a small-mouth type mouth.

[0004] The technical solution of this invention to solve the existing problems is: a multi-functional small cylindrical differential computer flat sewing machine, including a machine head, a base shell, a base plate component, a feed dog, a feed dog holder, a thread cutting mechanism, an upper and lower transmission mechanism, a lateral transmission mechanism, and a drive mechanism. The upper and lower transmission mechanism is used to drive the feed dog holder to move up and down. The upper and lower transmission mechanism includes a pair of feed dog lifting shafts rotatably mounted on the base plate component, a drive linkage assembly for driving the pair of feed dog lifting shafts to rotate, a second crank, and a feed dog lifting connecting rod for driving the second crank. Each feed dog lifting shaft has a movably eccentrically mounted conversion slider or conversion shaft at its corresponding end to the feed dog holder. A guiding sliding structure is provided between the conversion slider or conversion shaft and the feed dog holder. The drive linkage assembly includes a first crank and a pair of drive connecting rods. One end of each drive connecting rod is movably connected to the other end of the feed dog lifting shaft, and the other end of the pair of drive connecting rods is movably connected to the first crank. A crank connecting shaft is provided between the first crank and the second crank. A lateral transmission mechanism is used to drive the tooth holder seat to move laterally. This mechanism includes a feeding shaft, a feeding transmission crank, a feeding connecting rod movably mounted on the feeding transmission crank to drive the tooth holder seat to move laterally, and a feeding transmission shaft rotatably mounted on the base plate component to drive the feeding transmission crank to reciprocate. A fabric feeding crank is connected to the feeding shaft, and the fabric feeding crank is connected to the feeding connecting rod. A power transmission connecting rod assembly is provided between the feeding shaft and the feeding transmission shaft. The tooth holder seat has a receiving groove for accommodating the feeding transmission crank and the feeding connecting rod, and the feeding connecting rod is rotatably connected to one side wall of the receiving groove. A drive mechanism is used to provide power and drive the upper and lower transmission mechanisms and the lateral transmission mechanism to coordinate the movement of the feeding teeth. This drive mechanism includes a first cam or eccentric wheel and a second cam or eccentric wheel mounted on the same drive shaft. The first cam or eccentric wheel engages with the upper end of the tooth lifting connecting rod, and the second cam or eccentric wheel engages with the upper end of the feeding connecting rod.

[0005] The thread-cutting mechanism includes a fixed blade and a moving blade that cooperate with each other. The moving blade is equipped with a moving blade holder, which is connected to a rotating ring. The base plate component is located on one side of the rotating ring and rotatably mounted with a thread-cutting drive shaft. A first transmission structure is provided between the thread-cutting drive shaft and the rotating ring. A drive motor is provided on the bottom shell of the sewing machine. A second transmission structure is provided between the drive motor and the thread-cutting drive shaft. The feeding drive shaft is located below another lifting tooth shaft. As a further improvement, the drive mechanism includes a first eccentric wheel and / or a second eccentric wheel, and the eccentric wheel has an outer ring connected to a corresponding connecting rod.

[0006] As a further improvement, the first cam or eccentric wheel and the second cam or eccentric wheel are mounted on the same drive shaft; The thread-cutting mechanism includes a fixed blade and a moving blade that cooperate with each other. The moving blade is equipped with a moving blade holder, and the moving blade holder is connected to a rotating ring. The base plate component is located on one side of the rotating ring and is rotatably mounted with a thread-cutting drive shaft. A first transmission structure is provided between the thread-cutting drive shaft and the rotating ring. A drive motor is provided on the bottom shell of the sewing machine, and a second transmission structure is provided between the drive motor and the thread-cutting drive shaft.

[0007] The wire-cutting drive shaft is located below one lifting tooth shaft, and the feeding drive shaft is located below another lifting tooth shaft. The first transmission structure includes a driven gear mounted on a rotating ring and a corresponding driving gear mounted on the wire-cutting drive shaft. The rotating ring is sleeved on the lower shaft, and a bearing or rotating sleeve is provided between the rotating ring and the lower shaft. The wire-cutting drive shaft is mounted on the base plate component via the rotating sleeve or bearing. The moving knife holder includes a connecting handle for mounting the moving knife and a bent arm connecting the connecting handle and the rotating ring. The second transmission structure includes a pulley assembly and / or a transmission gear assembly located between the wire-cutting drive shaft and the drive motor. The drive motor is located inside the bottom shell. A motor bracket is provided inside the bottom shell, and the drive motor is mounted on the motor bracket. The moving knife is configured as an arc-shaped moving knife surrounding the rotary shuttle that cooperates with a fixed knife. The fixed knife is configured as an arc-shaped fixed knife surrounding the rotary shuttle that cooperates with the moving knife.

[0008] As a further improvement, the crank connecting shaft and the feeding shaft are rotatably mounted on the bottom shell; the crank connecting shaft, the feeding shaft, the tooth lifting shaft or the feeding transmission shaft are provided with mounting sleeves or bearings.

[0009] As a further improvement, the pair of tooth-lifting shafts and the pair of drive connecting rods are arranged on both sides of the lower shaft, the pair of drive connecting rods are arc-shaped curved connecting rods, and the lower ends of the pair of drive connecting rods are rotatably connected to the first crank; the lower shaft is arranged between the pair of drive connecting rods.

[0010] As a further improvement, the guiding sliding structure includes sliding guide grooves disposed on both sides of the dental arch support, and the conversion slider or conversion shaft is slidably disposed in the sliding guide grooves.

[0011] As a further improvement, the tooth-lifting shaft is provided with a conversion handle at the corresponding end of the tooth holder seat, and the conversion slider is movably mounted on the conversion handle, or the conversion shaft is mounted on the conversion handle; the transmission linkage assembly includes a third crank movably mounted on the feeding shaft and a small feeding shaft crank movably mounted on one end of the feeding transmission shaft, and a transmission linkage is movably connected between the small feeding shaft crank and the third crank; each driving linkage is also connected to the corresponding tooth-lifting shaft with a small shaft tooth-lifting crank, the small shaft tooth-lifting crank is mounted on the tooth-lifting shaft, and the other end of the small shaft tooth-lifting crank is movably connected to the driving linkage.

[0012] As a further improvement, a feeding swing plate assembly is also included, which is connected to the feeding crank to adjust the feeding tooth stroke position. A long feeding swing plate is rotatably connected between the feeding crank and the feeding connecting rod. The long feeding swing plate is coaxially connected to the first rotating shaft of the feeding connecting rod and is located in the feeding swing plate assembly. The long feeding swing plates can be configured as a pair, with the corresponding end of the feeding connecting rod clamped between the corresponding end of the pair of long feeding swing plates, and the feeding crank clamped between the corresponding other end of the pair of long feeding swing plates.

[0013] As a further improvement, the feeding swing plate assembly includes a short feeding swing plate, a needle adjuster, and a feeding swing seat rotatably mounted on the base plate component. The feeding swing seat has a groove, and one end of the short feeding swing plate is rotatably mounted on the inner wall of the groove of the feeding swing seat, while the other end is rotatably connected to the outer side of the first rotating shaft. A pair of short feeding swing plates are provided, and the pair of short feeding swing plates are sandwiched on the outer side of a pair of long feeding swing plates. The feeding swing plate assembly also includes a manual adjustment structure.

[0014] As a further improvement, the movable connection is a rotary connection.

[0015] Compared with existing technologies, this invention provides a drive mechanism for the feed toother, including an up-and-down transmission mechanism, a lateral transmission mechanism, a drive mechanism, and a wire-cutting mechanism. The up-and-down transmission mechanism includes a pair of tooth-lifting shafts rotatably mounted on the base plate. The lateral transmission mechanism includes a reciprocating feed transmission shaft rotatably mounted on the base plate. The tooth-lifting shafts can be driven by corresponding eccentric wheels or cams in the drive mechanism, combined with necessary connecting rods, cranks, and crank-connecting shafts. The feed transmission shaft can also be driven by corresponding eccentric wheels or cams in the drive mechanism, combined with necessary connecting rods, cranks, and feed shafts. Ultimately, the feed toother is driven up and down by a conversion slider or conversion shaft eccentrically mounted at the corresponding ends of the pair of tooth-lifting shafts. The feed crank is driven by the feed transmission shaft, and the feed crank, via a feed connecting rod, drives the feed toother to produce a lateral feeding action from one side wall of the receiving groove on the feed toother. The up-and-down transmission mechanism and the lateral transmission mechanism work together to continuously drive the feed toother to produce a feeding action.

[0016] The thread-cutting mechanism has a thread-cutting drive shaft rotatably mounted on one side of the rotating ring and on the base plate component. A drive motor on the base shell drives the drive shaft through a second transmission structure. The drive shaft drives the rotating ring through a first transmission structure. The moving blade holder located on the rotating ring drives the moving blade to cooperate with the fixed blade to cut the thread. The drive shaft and rotating ring drive the moving blade. The length of the drive shaft can be adjusted as needed to adapt to the transmission distance, and it can fully accommodate the need to increase the length of the small nozzle to meet the requirements of special sewing.

[0017] Its beneficial effect is that, using the sewing machine needle position as a base point, the length of the feed nozzle can be adjusted as needed by changing the lengths of a pair of feed dog shafts and the feed drive shaft. Simultaneously, the lengths of the feed shaft and the crank connecting shaft can be adjusted as needed to adapt to the overall length and volume of the sewing machine. The transmission structure of the pair of feed dog shafts, feed drive shaft, feed shaft, crank connecting shaft, connecting rod, and crank, as well as the thread cutting drive shaft, are no longer limited by the length of the transmission distance. The appropriate lengths can be set as needed to meet the requirements of the feed nozzle length. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the sewing machine nozzle type of the present invention.

[0019] Figure 2 This is a schematic diagram of the feeding tooth drive of the present invention.

[0020] Figure 3 yes Figure 2 Enlarged schematic diagram at point a.

[0021] Figure 4 This is a schematic diagram of the feed tooth drive of the present invention from one perspective.

[0022] Figure 5 yes Figure 4 Enlarged diagram of point b.

[0023] Figure 6 This is a schematic diagram of the feed tooth drive of the present invention from a second perspective.

[0024] Figure 7 yes Figure 6 Enlarged diagram of point c.

[0025] Figure 8 yes Figure 6 Enlarged diagram at point d.

[0026] Figure 9 This is a schematic diagram of the feed tooth drive of the present invention from a third perspective.

[0027] Figure 10 yes Figure 9 Enlarged diagram of point e.

[0028] Figure 11 This is a schematic diagram of the feeding swing plate assembly of the present invention from one perspective.

[0029] Figure 12 This is a schematic diagram of the feed tooth drive of the present invention from a fourth perspective.

[0030] Figure 13 yes Figure 12 Enlarged schematic diagram at point f.

[0031] Figure 14This is a partially enlarged schematic diagram of the present invention.

[0032] Figure 15 yes Figure 14 An enlarged schematic diagram at point g.

[0033] Figure 16 , Figure 17 , Figure 18 These are enlarged schematic diagrams of the wire-cutting mechanism from different perspectives. Detailed Implementation

[0034] See Figure 1-18 This implementation case, a multi-functional small cylindrical differential computer flat sewing machine, includes a machine head, a bottom shell 61, a bottom plate component 6, a feed dog 5, a feed dog holder 4, a thread cutting mechanism, an upper and lower transmission mechanism 2, a horizontal transmission mechanism 2, and a drive mechanism 3.

[0035] The upper and lower transmission mechanism 1 is used to drive the dental arch support 4 to move up and down. The upper and lower transmission mechanism 1 includes a pair of lifting shafts 10 rotatably mounted on the base plate component 6, a drive linkage assembly for driving the pair of lifting shafts 10 to rotate, a second crank 12, and a lifting linkage 13 for driving the second crank 12. Each lifting shaft 10 is eccentrically mounted with a conversion slider 11 or a conversion shaft at the corresponding end of the dental arch support 4, so that the conversion slider 11 or conversion shaft is eccentrically set with the lifting shaft 10. A guiding sliding structure is provided between the conversion slider 11 or conversion shaft and the dental arch support 4. The drive linkage assembly includes a first crank 14 and a pair of drive linkages 15. One end of each drive linkage 15 is movably connected to the other end of the lifting shaft 10, and the other end of the pair of drive linkages 15 is movably connected to the first crank 14. A crank connecting shaft 16 is provided between the first crank 14 and the second crank 12. A transverse transmission mechanism 2 is used to drive the tooth frame seat 4 to move laterally. The transverse transmission mechanism 2 includes a feeding shaft 23, a feeding transmission crank 21, a feeding connecting rod 20 movably mounted on the feeding transmission crank 21 to drive the tooth frame seat 4 to move laterally, and a feeding transmission shaft 22 rotatably mounted on the base plate component 6 to drive the feeding transmission crank 21 to reciprocate. A fabric feeding crank 24 is connected to the feeding shaft 23, and the fabric feeding crank 24 is connected to the feeding connecting rod 25. A power transmission connecting rod assembly is provided between the feeding shaft 23 and the feeding transmission shaft 22. The tooth frame seat 4 is provided with a receiving groove 42 to accommodate the feeding transmission crank 21 and the feeding connecting rod 20. The feeding connecting rod 20 is rotatably connected to one side wall of the receiving groove 42. Specifically, the tooth frame seat 4 can be rotatably connected via a second rotating shaft 201. The tooth frame seat 4 is provided with a first shaft hole 43 at a corresponding position on one side wall of the receiving groove 42. The drive mechanism 3 provides power to drive the upper and lower transmission mechanism 1 and the lateral transmission mechanism 2 in a coordinated manner to drive the feed tooth 5. The drive mechanism 3 includes a first cam or eccentric wheel and a second cam or eccentric wheel mounted on the same drive shaft. The first cam or eccentric wheel engages with the upper end of the tooth-lifting connecting rod 13, and the second cam or eccentric wheel engages with the upper end of the feed connecting rod 25. The first cam or eccentric wheel and the second cam or eccentric wheel are mounted on the same drive shaft, such as the upper shaft of a sewing machine.

[0036] To facilitate manufacturing and control, and improve driving precision, the drive mechanism includes a first eccentric wheel 31 and / or a second eccentric wheel 32, each eccentric wheel having an outer ring connected to a corresponding connecting rod. The eccentric wheels offer higher precision and are easier to manufacture.

[0037] The crank connecting shaft 16 and the feeding shaft 23 are rotatably mounted on the bottom shell 61; the crank connecting shaft 16, the feeding shaft 23, the lifting tooth shaft 10, or the feeding transmission shaft 22 are provided with mounting sleeves 7 or bearings. That is, the crank connecting shaft 16 and the feeding shaft 23 are mounted on the bottom shell 61 via sleeves or bearings, and the lifting tooth shaft 10 and the feeding transmission shaft 22 are mounted on the base plate component 6 via bearings or sleeves.

[0038] Preferably, for ease of layout and to accommodate the existing base plate component 6, the pair of lifting tooth shafts 10 and the pair of driving connecting rods 15 are arranged on both sides of the lower shaft 9. The pair of driving connecting rods 15 are arc-shaped curved connecting rods, and the lower ends of the pair of driving connecting rods 15 are rotatably connected to the first crank 14. The lower shaft 9 is arranged between the pair of driving connecting rods 15.

[0039] The main transmission components of this invention, namely the crank connecting shaft 16, the feeding shaft 23, the tooth lifting shaft 10, and the feeding transmission shaft 22, are all shaft drives. The appropriate length can be set according to actual needs, and the transmission is no longer restricted by distance. Therefore, by changing the length of the tooth lifting shaft 10 and the feeding transmission shaft 22, the length of the small mouth can be increased or decreased to adapt to special sewing.

[0040] The guiding sliding structure preferably includes sliding guide grooves 41 disposed on both sides of the dental arch support 4, and the conversion slider 11 or conversion shaft is slidably disposed within the sliding guide grooves 41. Of course, other existing technical structures can be used to drive the dental arch support 4 to move up and down by rotating with the tooth lifting shaft 10.

[0041] To facilitate installation and smooth operation, and to accommodate the space at the base plate component 6 of the sewing machine, the lifting tooth shaft 10 is provided with a conversion handle 17 at the corresponding end of the tooth holder 4. The conversion handle 17 allows for the eccentric installation of the conversion slider 11 or conversion shaft relative to the lifting tooth shaft 10, providing a larger fitting space between the conversion slider 11 or conversion shaft and the lifting tooth shaft 10. The conversion slider 11 is movably mounted on the conversion handle 17; if it is a conversion shaft, it can be fixedly mounted on the conversion handle 17. Each drive linkage 15 is also connected to the corresponding lifting tooth shaft 10 by a small shaft lifting tooth crank 18. The small shaft lifting tooth crank 18 is mounted on the lifting tooth shaft 10, and its other end is movably connected to the drive linkage 15. The transmission linkage assembly includes a third crank 26 movably mounted on the feed shaft 23 and a feed shaft crank 27 movably mounted on one end of the feed transmission shaft 22. A transmission linkage 28 is movably connected between the feed shaft crank 27 and the third crank 26.

[0042] It also includes a feeding swing plate assembly 8 that connects to the feeding crank 24 to adjust the stroke position of the feeding teeth 5. The feeding crank 24 and the feeding connecting rod 25 are rotatably connected by a feeding long swing plate 29. The feeding long swing plate 29 and the feeding connecting rod 25 are rotatably connected at the first rotating shaft and coaxially connected in the feeding swing plate assembly 8. The feeding long swing plate 29 can be configured as a pair. The corresponding end of the feeding connecting rod 25 is clamped between the corresponding end of the pair of feeding long swing plates 29, and the feeding crank 24 is clamped between the corresponding other end of the pair of feeding long swing plates 29.

[0043] The feeding swing plate assembly 8 includes a short feeding swing plate 80, a needle adjuster 81, and a feeding swing seat 82 rotatably mounted on the base plate component 6. The feeding swing seat 82 has a groove 83. One end of the short feeding swing plate 80 is rotatably mounted on the inner wall of the groove 83 of the feeding swing seat 82, and the other end is rotatably connected to the outer side of the first rotating shaft. A pair of short feeding swing plates 80 are provided, and the pair of short feeding swing plates 80 are sandwiched on the outer side of a pair of long feeding swing plates 29. The needle adjuster 81 may include an adjustment block 85 rotatably mounted in the machine housing, and an adjustment linkage assembly 84 that movably connects the adjustment block 85 and the feeding swing seat 82 to adjust the movement of the feeding swing seat 82. The adjustment block 85 can be manually rotated, driven by a motor, or driven by other power sources on the sewing machine. Specifically, the adjustment block 85 may also cooperate with an adjustment screw and / or be driven by a rotating shaft. The adjustment block 85 is adjusted by the adjustment screw or the rotating shaft. The feeding swing plate assembly 8 also includes a manual adjustment structure.

[0044] The aforementioned movable connection can adopt existing technical structures that enable drive transmission. For a rotating connection, a rotating shaft and a matching shaft hole can be used.

[0045] When using the structure of this invention, the installation and operation positions of each component are pre-adjusted, and the operation position and feeding path of the feed tooth 5 are adjusted by the drive mechanism 3, the lower transmission mechanism 1 and the transverse transmission mechanism 2.

[0046] The drive shaft (upper shaft) drives the first and second eccentric wheels of the drive mechanism 3 to rotate.

[0047] The tooth-lifting connecting rod 13, which cooperates with the first eccentric wheel 31 on the upper and lower transmission mechanism 1, reciprocates around the crank connecting shaft 16 with the rotating first eccentric wheel. The first crank 14, connected to the crank connecting shaft 16, swings back and forth with the connecting shaft 16. The swinging first crank 14 drives a pair of drive connecting rods 15 to reciprocate. The pair of reciprocating drive connecting rods 15 can directly drive a pair of tooth-lifting shafts 10 to reciprocate. In this embodiment, the pair of drive connecting rods 15 can drive a pair of tooth-lifting shafts 10 to rotate through the small shaft tooth-lifting crank 18. Under the action of the conversion slider 11 or conversion shaft that is eccentrically set with the tooth-lifting shaft 10, the reciprocating tooth-lifting shaft 10 cooperates with the corresponding sliding guide groove 41 of the tooth frame seat 4. With the reciprocating rotation of the tooth-lifting shaft 10, the eccentrically set conversion slider 11 or conversion shaft cooperates with the sliding guide groove 41, driving the tooth frame seat 4 to move up and down reciprocally. The conversion slider 11 or conversion shaft is preferably mounted on the conversion handle 17, and under the action of the conversion handle 17 on the tooth lifting shaft 10, it cooperates with the sliding guide groove 41.

[0048] Simultaneously, the feeding connecting rod 25, which cooperates with the second eccentric wheel 32 on the transverse transmission mechanism 2, drives the feeding shaft 23 to reciprocate as the second eccentric wheel 32 rotates. The reciprocating feeding shaft 23 drives the transmission connecting rod assembly. The transmission connecting rod assembly drives the feeding transmission shaft 22 to reciprocate through the third crank 26, the transmission connecting rod 28, and the feeding small shaft crank 27, which are movably connected in sequence. The reciprocating feeding transmission shaft 22 drives the feeding transmission crank 21 to swing back and forth. The reciprocating feeding transmission crank 21 pulls the movably connected feeding connecting rod 20 to move back and forth. The reciprocating feeding connecting rod 20 cooperates with the first shaft hole 43 of the tooth holder 4 through the second rotating shaft 201, pulling the tooth holder 4 to move back and forth to generate feeding movement, thereby realizing the feeding action. Since the feeding connecting rod 20 is movably mounted on the feeding transmission crank 21 and the feeding connecting rod 20 is engaged with the shaft hole of the tooth holder 4, when the feeding connecting rod 20 is pulled by the feeding transmission crank 21, the feeding connecting rod 20 pulls the tooth holder 4 to move, and the reciprocating motion of the tooth holder 4 with the upper and lower transmission mechanism does not interfere with each other.

[0049] Under the combined action of the upper and lower transmission mechanism 1 and the horizontal transmission mechanism 2, the tooth holder 4 reciprocates up, down, forward, and backward according to the preset feeding path. The feeding tooth 5, driven by the tooth holder 4, feeds the fabric according to the preset path.

[0050] Preferably, the initial feeding position and / or stroke of the feed tooth 5 can be adjusted by adjusting the adjusting block 85 of the feed swing plate assembly 8 and by adjusting the connecting rod assembly 84 to drive the movable feed swing seat 82, so as to adjust the sewing stitch length. Specifically, by manually or mechanically adjusting the adjusting block 85, the adjusting rod assembly 84 drives the movable feed swing seat 82 to rotate. Since the feed short swing plate 80 and the feed long swing plate 29 are coaxially mounted through the first rotating shaft, the rotating feed swing seat 82 can change the movement trajectory of the feed long swing plate 29 through the feed short swing plate 80, thereby changing the trajectory of the feed connecting rod 25 driving the feed long swing plate 29, and ultimately changing the stroke, initial position and / or speed of the feed tooth 5.

[0051] The mechanism of the present invention also includes a fixed blade 1a mounted on the base plate component 6, a movable blade 2a that cooperates with the fixed blade 1a to cut the wire, a movable blade holder 3a, a rotating ring 4a connected to the movable blade holder 3a, and a wire-cutting transmission shaft 5a located on one side of the rotating ring 4a and rotatably mounted on the base plate component 6. A first transmission structure is provided between the rotating ring 4a and the wire-cutting transmission shaft 5a. A drive motor 51a is provided on the bottom shell 61. A second transmission structure is provided between the drive motor 51a and the wire-cutting transmission shaft 5a. The fixed blade 1a and its cooperating movable blade 2a are typically positioned between the lower part of the needle plate and the upper part of the rotary hook. When thread cutting is required or the thread cutting action is completed, the drive motor 51a, in conjunction with the second transmission structure, drives the thread cutting drive shaft 5a. The thread cutting drive shaft 5a drives the rotating ring 4a through the first transmission structure. The rotating ring, through the movable blade holder 4, drives the movable blade 2a to perform the thread cutting action. The movable blade 2a slides relative to the blade edge of the fixed blade 1a, mates with the fixed blade 1a, and completes the thread cutting action. After this, the drive motor 51a drives the movable blade 2a to reset. The thread cutting drive shaft 5a is located below one lifting tooth shaft, and the feeding drive shaft 22 is located below another lifting tooth shaft.

[0052] In this embodiment, the first transmission structure includes a driven gear 11 disposed on the rotating ring 4a and a corresponding driving gear 12a disposed on the wire cutting transmission shaft 5a. The structure is minimized by driving the moving blade through the gears.

[0053] The rotating ring 4a is sleeved on the lower shaft 41a, and a bearing or rotating sleeve is provided between the rotating ring 4a and the lower shaft 41a. The lower shaft 41a is typically used to connect a rotary hook. The rotating ring 4a can be coaxially arranged with the lower shaft 41a. The wire cutting drive shaft 5a can be arranged parallel to the lower shaft 41a.

[0054] The wire-cutting drive shaft 5a is mounted on the base plate component 6 via a rotating sleeve or bearing.

[0055] To simplify and reduce the size of the moving tool holder 3a and the rotating ring 4a, the moving tool holder 3a includes a connecting handle 21a for mounting the moving tool 2a and a bent arm portion 22a connecting the connecting handle 21a and the rotating ring 4a. The connecting handle 21a and the bent arm portion 22a are provided to meet the transmission requirements, making the rotating ring 4a and the moving tool holder 3a lighter and more compact.

[0056] The second transmission structure includes a pulley assembly 52a and / or a transmission gear assembly disposed between the wire-cutting transmission shaft 5a and the drive motor 51a. The pulley assembly 52a includes a driven pulley disposed on the wire-cutting transmission shaft 5a, a drive pulley disposed on the motor shaft of the drive motor 51a, and a synchronous belt connecting the driven pulley and the drive pulley.

[0057] The drive motor 51a is disposed inside the bottom shell 61; the bottom shell 61 is provided with a motor bracket 62, and the drive motor 51a is mounted on the motor bracket 62.

[0058] See Figure 17 , 18 As a further preferred embodiment, the moving blade 2a is configured as an arc-shaped moving blade that rotates around the rotary shuttle and cooperates with the fixed blade 1a. The fixed blade 1a is configured as an arc-shaped fixed blade that rotates around the rotary shuttle and cooperates with the moving blade 2a. The arc-shaped fixed blade 1a and moving blade 2a can better adapt to the rotary shuttle, keep the overall structure compact, and can be easily installed in the base plate component 6.

[0059] The drive structure of the aforementioned thread-cutting blade 2a is simple and compact. The blade 2a is driven by the thread-cutting drive shaft 5a and the rotating ring 3a. The length of the thread-cutting drive shaft 5a can be adjusted as needed to adapt to the transmission distance. It can fully adapt to the need to increase the length of the small nozzle and meet the needs of special sewing.

Claims

1. A multi-functional small cylindrical differential computer flat sewing machine, comprising a machine head, a base shell, a base plate component, a feed dog, a feed dog holder, and a thread cutting mechanism, characterized in that: It also includes an up-and-down transmission mechanism for driving the dental arch support to move up and down. The up-and-down transmission mechanism includes a pair of lifting shafts rotatably mounted on the base plate component, a drive linkage assembly for driving the pair of lifting shafts to rotate, a second crank, and a lifting linkage for driving the second crank. Each lifting shaft has a movable conversion slider or conversion shaft eccentrically mounted at the corresponding end of the dental arch support. A guide sliding structure is provided between the conversion slider or conversion shaft and the dental arch support. The drive linkage assembly includes a first crank and a pair of drive linkages. One end of each drive linkage is movably connected to the other end of the lifting shaft, and the other end of the pair of drive linkages is movably connected to the first crank. A crank connecting shaft is provided between the first crank and the second crank. A lateral transmission mechanism is used to drive the tooth holder seat to move laterally. The lateral transmission mechanism includes a feeding shaft, a feeding transmission crank, a feeding connecting rod movably mounted on the feeding transmission crank to drive the tooth holder seat to move laterally, and a feeding transmission shaft rotatably mounted on the base plate component to drive the feeding transmission crank to reciprocate. A fabric feeding crank is connected to the feeding shaft, and the fabric feeding crank is connected to the feeding connecting rod. A transmission connecting rod assembly for transmitting power is provided between the feeding shaft and the feeding transmission shaft. The tooth holder seat has a receiving groove for accommodating the feeding transmission crank and the feeding connecting rod, and the feeding connecting rod is rotatably connected to one side wall of the receiving groove. A drive mechanism is used to provide power and drive the upper and lower transmission mechanisms and the lateral transmission mechanism to coordinate the driving of the feeding tooth action. The drive mechanism includes a first cam or eccentric wheel and a second cam or eccentric wheel mounted on the same drive shaft. The first cam or eccentric wheel cooperates with the upper end of the tooth lifting connecting rod, and the second cam or eccentric wheel cooperates with the upper end of the feeding connecting rod. The thread-cutting mechanism includes a fixed blade and a moving blade that cooperate with each other. The moving blade is equipped with a moving blade holder, and the moving blade holder is connected to a rotating ring. The base plate component is located on one side of the rotating ring and is rotatably mounted with a thread-cutting drive shaft. A first transmission structure is provided between the thread-cutting drive shaft and the rotating ring. A drive motor is provided on the bottom shell of the sewing machine, and a second transmission structure is provided between the drive motor and the thread-cutting drive shaft.

2. The multifunctional small cylindrical differential computer flat sewing machine as described in claim 1, characterized in that: The drive mechanism includes a first eccentric wheel and / or a second eccentric wheel, wherein the eccentric wheel has an outer ring connected to a corresponding connecting rod.

3. The multifunctional small cylindrical differential computer flat sewing machine as described in claim 1, characterized in that: The first cam or eccentric wheel and the second cam or eccentric wheel are mounted on the same drive shaft; the wire cutting drive shaft is located below one tooth lifting shaft, and the feeding drive shaft is located below another tooth lifting shaft; the first transmission structure includes a driven gear mounted on a rotating ring and a corresponding drive gear mounted on the wire cutting drive shaft; the rotating ring is sleeved on the lower shaft, and a bearing or rotating sleeve is provided between the rotating ring and the lower shaft; the wire cutting drive shaft is mounted on the base plate component via the rotating sleeve or bearing; the moving blade holder includes a connecting handle for mounting the moving blade and a bent arm connecting the connecting handle and the rotating ring; the second transmission structure includes a pulley assembly and / or a transmission gear assembly located between the wire cutting drive shaft and the drive motor; the drive motor is located inside the bottom shell; The bottom shell is equipped with a motor bracket, and the drive motor is mounted on the motor bracket; the moving blade is configured as an arc-shaped moving blade that rotates around the rotary shuttle and cooperates with the fixed blade; the fixed blade is configured as an arc-shaped fixed blade that rotates around the rotary shuttle and cooperates with the moving blade.

4. The multifunctional small cylindrical differential computer flat sewing machine as described in claim 1, characterized in that: The crank connecting shaft and the feeding shaft are rotatably mounted on the bottom shell; the crank connecting shaft, the feeding shaft, the lifting shaft or the feeding transmission shaft are provided with mounting sleeves or bearings.

5. The multifunctional small cylindrical differential computer flat sewing machine as described in claim 1, characterized in that: The pair of tooth-lifting shafts and the pair of drive connecting rods are arranged on both sides of the lower shaft. The pair of drive connecting rods are arc-shaped curved connecting rods, and the lower ends of the pair of drive connecting rods are rotatably connected to the first crank. The lower shaft is arranged between the pair of drive connecting rods.

6. The multifunctional small cylindrical differential computer flat sewing machine as described in claim 1, characterized in that: The guiding sliding structure includes sliding guide grooves disposed on both sides of the dental arch support, and the conversion slider or conversion shaft is slidably disposed in the sliding guide grooves.

7. The multifunctional small cylindrical differential computer flat sewing machine as described in claim 1, characterized in that: The tooth-lifting shaft is provided with a conversion handle at the corresponding end of the tooth holder seat. The conversion slider is movably mounted on the conversion handle, or the conversion shaft is mounted on the conversion handle. The transmission linkage assembly includes a third crank movably mounted on the feeding shaft and a small feeding shaft crank movably mounted on one end of the feeding transmission shaft. A transmission linkage is movably connected between the small feeding shaft crank and the third crank. Each driving linkage is also connected to the corresponding tooth-lifting shaft with a small shaft tooth-lifting crank. The small shaft tooth-lifting crank is mounted on the tooth-lifting shaft, and the other end of the small shaft tooth-lifting crank is movably connected to the driving linkage.

8. The multifunctional small cylindrical differential computer flat sewing machine as described in claim 1, characterized in that: It also includes a feeding swing plate assembly that connects to the feeding crank to adjust the feeding tooth stroke position. The feeding crank and the feeding connecting rod are rotatably connected by a long feeding swing plate. The long feeding swing plate and the feeding connecting rod are rotatably connected at the first rotating shaft and coaxially disposed in the feeding swing plate assembly. The long feeding swing plates can be configured as a pair. The corresponding end of the feeding connecting rod is clamped between the corresponding end of the pair of long feeding swing plates, and the feeding crank is clamped between the corresponding other end of the pair of long feeding swing plates.

9. The multifunctional small cylindrical differential computer flat sewing machine as described in claim 8, characterized in that: The feeding swing plate assembly includes a short feeding swing plate, a needle adjuster, and a feeding swing seat rotatably mounted on a base plate component. The feeding swing seat has a groove. One end of the short feeding swing plate is rotatably mounted on the inner wall of the groove of the feeding swing seat, and the other end is rotatably connected to the outer side of the first rotating shaft. A pair of short feeding swing plates are provided, and the pair of short feeding swing plates are sandwiched on the outer side of a pair of long feeding swing plates. The feeding swing plate assembly also includes a manual adjustment structure.

10. The multifunctional small cylindrical differential computer flat sewing machine as described in claim 1, 7, or 8, characterized in that: The movable connection is a rotary connection.

Images