Thread trimming and loosening and presser foot lifting mechanism of flat seaming machine

Abstract

The invention relates to a flat seaming machine thread trimming and loosening and presser foot lifting mechanism which comprises a driving motor and a presser foot lifting transmission shaft, the driving motor is longitudinally arranged, a driving cam is arranged on an output shaft at the upper end of the driving motor, and a driving crank is arranged at the end, corresponding to the driving cam, of the presser foot lifting transmission shaft. A guide transmission mechanism is further arranged at the upper end of the driving motor and comprises a guide seat, a guide block is arranged on the guide seat, a guide structure is arranged between the guide block and the guide seat, a driving plane is arranged on the side, close to the driving crank, of the guide block, and the free end of the driving crank abuts against the driving plane. A roller is further arranged on the guide block and is matched with the outer edge of the driving cam; an existing structure is correspondingly improved, the guide transmission mechanism is additionally arranged in front of the crank and the cam at the output end of the motor, the area of the driving plane of the guide transmission mechanism is increased, the presser foot lifting rod is pushed to rotate through the driving plane, and therefore the requirement for installation accuracy of the presser foot lifting crank is lowered.

Description

Technical Field

[0001] The invention relates to sewing machine technology, in particular to a thread trimming, loosening and presser foot lifting mechanism for a stretch sewing machine. Background Art

[0002] The presser foot lifting mechanism of the existing interlock sewing machine is disclosed in the invention patent CN115522334A, which discloses a presser foot lifting mechanism and an interlock sewing machine. The presser foot lifting mechanism of the interlock sewing machine includes a presser foot lifting assembly and a driving motor (1), characterized in that the upper end output shaft of the driving motor drives the presser foot lifting assembly, the presser foot lifting assembly includes a presser foot lifting shaft, the rear end of the presser foot lifting shaft is equipped with a rear presser foot crank, the front end of the presser foot lifting shaft is equipped with a front presser foot crank, and the front presser foot crank drives the presser foot rod to move up and down; an upper cam is installed on the upper end output shaft, and a spherical sleeve is installed at the end of the rear presser foot crank; the working curved surface of the upper cam abuts against the spherical sleeve.

[0003] In the above structure, the outer edge of the cam abuts against the spherical sleeve. During operation, the cam rotates horizontally and the spherical sleeve rotates up and down. The contact point between the cam and the spherical sleeve is unstable and will rotate according to the rotation of the presser foot lifter rod. Therefore, high requirements are placed on the assembly accuracy of the presser foot lifter crank, and higher requirements are placed on the accuracy of parts and assembly. Summary of the invention

[0004] The purpose of the present invention is to provide a thread trimming, loosening and presser foot lifting mechanism for a flat sewing machine, to make corresponding improvements to the existing structure, and to add a guide transmission mechanism between the crank and the cam at the output end of the motor, and to increase the area of ​​the driving plane of the guide transmission mechanism, so that the presser foot lifting rod is pushed to rotate through the driving plane, thereby reducing the installation accuracy requirements of the presser foot lifting crank.

[0005] To achieve the above purpose, the following technical solutions are adopted: A presser foot lifting mechanism for a stretch sewing machine comprises a driving motor and a presser foot lifting transmission shaft, the driving motor is arranged longitudinally, a driving cam is arranged on the output shaft at the upper end of the driving motor, and a driving crank is arranged at one end of the presser foot lifting transmission shaft corresponding to the driving cam, and the characteristic is that a guide transmission mechanism is also arranged at the upper end of the driving motor, the guide transmission mechanism comprises a guide seat, the guide seat is fixedly connected to the upper end of the driving motor, a guide block is arranged on the guide seat, a guide structure is arranged between the guide block and the guide seat, a driving plane is arranged on the side of the guide block close to the driving crank, the free end of the driving crank abuts on the driving plane, and a roller is also arranged on the guide block, and the roller cooperates with the outer edge of the driving cam.

[0006] The axial direction of the roller is parallel to the axial direction of the output shaft of the driving motor, and the roller is pivotally connected to the bottom of the guide block.

[0007] The driving plane is formed by raising the end surface of the guide block, and the moving direction of the guide structure is perpendicular to the driving plane. The free end of the driving crank is movably sleeved with a driving roller, and the driving roller and the driving plane are in rolling cooperation.

[0008] The driving cam includes an integral cam and a fixed sleeve, the cam is located below the fixed sleeve, and a radial screw hole is provided on the fixed sleeve; the guide block is provided with an avoidance hole at a position corresponding to the fixed sleeve, the fixed sleeve is accommodated in the avoidance hole, the cam is located below the guide block, and the roller is located outside the avoidance hole.

[0009] The output end of the lower end of the driving motor is fixedly connected with a lower cam, and the lower cam is connected with the thread trimming transmission mechanism and the thread loosening transmission mechanism through a transmission lever; the transmission lever is pivotally connected to the lower end of the driving motor, and the transmission lever has a U-shaped input end, and the two ends of the U-shaped input end are distributed on both sides of the lower cam and contact with the outer edge of the lower cam, and the output end of the transmission lever is movably connected with the transmission connecting rod through a pivot, and the two ends of the transmission connecting rod are respectively connected with the thread trimming transmission mechanism and the thread loosening transmission mechanism.

[0010] Rollers are pivotally connected to the two ends of the U-shaped input end, and the two rollers are in rolling cooperation with the outer edge surface of the lower cam.

[0011] The transmission connecting rod is an L-shaped structure, which includes a transverse part and a longitudinal part. The output end of the transmission lever is pivotally connected to the middle part of the transverse part through a pivot, the end of the transverse part is connected to the thread cutting transmission mechanism, and the end of the longitudinal part is connected to the thread loosening transmission mechanism.

[0012] The present invention adds a guide transmission mechanism between the output end of the driving motor and the driving crank of the presser foot transmission shaft. The roller at the bottom of the guide transmission mechanism always maintains a horizontal position, and the rolling fit stability of the roller and the outer edge of the driving cam is good; in addition, the free driving roller of the driving crank and the driving plane also adopt rolling fit. The present invention increases the redundancy between the rolling fits of the components, thereby reducing the installation accuracy requirements of the presser foot lifting crank, and has the characteristics of easy installation and good stability. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a structural schematic diagram of the present invention; Figure 2 It is a structural schematic diagram of another aspect of the present invention; Figure 3 It is a schematic diagram of the decomposition structure of the present invention; Figure 4 It is a structural schematic diagram of the guide transmission mechanism and the presser foot lifting transmission shaft of the present invention; Figure 5 It is a structural schematic diagram of the bottom of the present invention (I); Figure 6 It is a structural schematic diagram of the bottom of the present invention (II); Figure 7 It is a structural schematic diagram of the bottom of the present invention (III); Implementation

[0014] like Figure 1-7 As shown, a presser foot lifting mechanism of a flat sewing machine includes a driving motor 1 and a presser foot lifting transmission shaft 2. The driving motor 1 is arranged longitudinally, and a driving cam 3 is arranged on the output shaft at the upper end of the driving motor 1. A driving crank 4 is arranged at one end of the presser foot lifting transmission shaft 2 corresponding to the driving cam 3. A guide transmission mechanism 5 is also arranged at the upper end of the driving motor 1. The guide transmission mechanism 5 includes a guide seat 51, and the guide seat 51 is fixedly connected to the upper end of the driving motor 1. A guide block 52 is arranged on the guide seat 51. A guide structure is arranged between the guide block 52 and the guide seat 51. A driving plane 53 is arranged on the side of the guide block 52 close to the driving crank. The driving plane 53 is formed by raising the end face of the guide block 52. The movement direction of the guide structure is perpendicular to the driving plane 53. The free end of the driving crank 4 is movably sleeved with a driving roller 41, and the driving roller 41 and the driving plane 53 are rollingly matched.

[0015] A roller 54 is also provided on the guide block 52. The roller 54 is pivotally connected to the bottom of the guide block 52. The roller 54 cooperates with the outer edge of the driving cam 3. The axial direction of the roller 54 is parallel to the axial direction of the output shaft of the driving motor 1. The driving cam 3 includes an integral cam 31 and a fixed sleeve 32. The cam 31 is located below the fixed sleeve 32. The fixed sleeve 32 is provided with a radial screw hole 33. The guide block 52 is provided with an avoidance hole 55 at the position corresponding to the fixed sleeve. The fixed sleeve 32 is accommodated in the avoidance hole 55. The cam 31 is located below the guide block 52, and the roller 54 is located on the periphery of the avoidance hole 55.

[0016] The output end of the lower end of the driving motor 1 is fixedly connected with a lower cam 6, and the lower cam 6 is connected to the thread cutting transmission mechanism and the thread loosening transmission mechanism through a transmission lever 7; the transmission lever 7 is pivoted at the lower end of the driving motor 1, and the transmission lever 7 has a U-shaped input end 71, and rollers 72 are pivoted at both ends of the U-shaped input end 7, and the two rollers 72 are rollingly matched with the outer edge surface of the lower cam 6; the transmission connecting rod 9 is an L-shaped structure, which includes a transverse portion 91 and a longitudinal portion 92 respectively. The output end of the transmission lever 7 is pivoted at the middle part of the transverse portion 91 through a pivot 8, and the end of the transverse portion 91 is connected to the thread cutting transmission mechanism, and the end of the longitudinal portion 92 is connected to the thread loosening transmission mechanism.

[0017] The transmission lever 7 of the present invention adopts a U-shaped input end, and the rollers 72 at both ends of the U-shaped input end 71 always keep in contact with the lower cam 6, so there will be no impact sound during operation, which is more silent.

[0018] At the same time, when the present invention is working, the driving motor 1 drives the driving cam 3 to rotate, and the driving cam 3 pushes the guide block to move along the guide mechanism toward the driving crank side through the roller 54, and the guide block pushes the driving roller through the driving plane, and then drives the presser foot lifting transmission shaft 2 to rotate through the driving crank to realize the presser foot lifting work; after the driving cam 3 is reset, the presser foot device spring is used to automatically reset the guide transmission mechanism 5 through the presser foot lifting transmission shaft 2, so that the roller 54 always keeps in contact with the driving cam.

[0019] The present invention adds a guide transmission mechanism between the output end of the driving motor and the driving crank of the presser foot transmission shaft. The driving cam roller at the bottom of the guide transmission mechanism always maintains a horizontal position, and the rolling fit stability between the roller and the outer edge of the driving cam is good; in addition, the free driving roller of the driving crank and the driving plane also adopt rolling fit. The present invention increases the redundancy between the rolling fits of the components, thereby reducing the installation accuracy requirements of the presser foot lifting crank, and has the characteristics of easy installation and good stability.

Claims

1. A thread trimming, loosening and presser foot lifting mechanism for a flat sewing machine, comprising a drive motor (1) and a presser foot lifting transmission shaft (2), wherein the drive motor (1) is arranged longitudinally, a drive cam (3) is arranged on the output shaft at the upper end of the drive motor (1), and a drive crank (4) is arranged at one end of the presser foot lifting transmission shaft (2) corresponding to the drive cam (3), characterized in that: A guide transmission mechanism (5) is also provided at the upper end of the drive motor (1), the guide transmission mechanism (5) comprising a guide seat (51), the guide seat (51) being fixedly connected to the upper end of the drive motor (1), a guide block (52) being provided on the guide seat (51), a guide structure being provided between the guide block (52) and the guide seat (51), a drive plane (53) being provided on the side of the guide block (52) close to the drive crank, the free end of the drive crank (4) being in contact with the drive plane (53), a roller (54) being provided on the guide block (52), the roller (54) being engaged with the outer edge of the drive cam (3).

2. A thread trimming, loosening and presser foot lifting mechanism for a flat sewing machine as claimed in claim 1, characterized in that: The axial direction of the roller (54) is parallel to the axial direction of the output shaft of the drive motor (1), and the roller (54) is pivotally connected to the bottom of the guide block (52).

3. A thread trimming, loosening and presser foot lifting mechanism for a flat sewing machine as claimed in claim 1, characterized in that: The driving plane (53) is formed by raising the end surface of the guide block (52); the movement direction of the guide structure is perpendicular to the driving plane (53); the free end of the driving crank (4) is movably sleeved with a driving roller (41); the driving roller (41) and the driving plane (53) are in rolling engagement.

4. A thread trimming, loosening and presser foot lifting mechanism for a flat sewing machine as claimed in claim 2, characterized in that: The driving cam (3) comprises an integrally structured cam (31) and a fixing sleeve (32), the cam (31) being located below the fixing sleeve (32), and the fixing sleeve (32) being provided with a radial screw hole (33); the guide block (52) being provided with an avoidance hole (55) at a position corresponding to the fixing sleeve, the fixing sleeve (32) being accommodated in the avoidance hole (55), the cam (31) being located below the guide block (52), and the roller (54) being located at the periphery of the avoidance hole (55).

5. A thread trimming, loosening and presser foot lifting mechanism for a flat sewing machine as claimed in claim 1, characterized in that: The output end of the lower end of the driving motor (1) is fixedly connected to a lower cam (6), and the lower cam (6) is connected to a thread trimming transmission mechanism and a thread loosening transmission mechanism via a transmission lever (7); the transmission lever (7) is pivotally connected to the lower end of the driving motor (1), and the transmission lever (7) has a U-shaped input end (71), and two ends of the U-shaped input end (71) are distributed on both sides of the lower cam (6) and contact the outer edge of the lower cam; the output end of the transmission lever (7) is movably connected to a transmission connecting rod (9) via a pivot (8), and two ends of the transmission connecting rod (9) are respectively connected to the thread trimming transmission mechanism and the thread loosening transmission mechanism.

6. A thread trimming, loosening and presser foot lifting mechanism for a flat sewing machine as claimed in claim 5, characterized in that: Rollers (72) are pivotally connected to both ends of the U-shaped input end (7), and the two rollers (72) are in rolling engagement with the outer edge surface of the lower cam (6).

7. A thread trimming, loosening and presser foot lifting mechanism for a flat sewing machine as claimed in claim 5, characterized in that: The transmission connecting rod (9) is an L-shaped structure, comprising a transverse portion (91) and a longitudinal portion (92). The output end of the transmission lever (7) is pivotally connected to the middle of the transverse portion (91) via a pivot (8). The end of the transverse portion (91) is connected to a thread cutting transmission mechanism, and the end of the longitudinal portion (92) is connected to a thread loosening transmission mechanism.

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