CN217579311U - Thread cutting mechanism of zigzag sewing machine - Google Patents

Abstract

The utility model relates to a zigzag sewing machine thread trimming mechanism, it is installed in zigzag sewing machine body, zigzag sewing machine body includes casing, base, motor, main shaft, thread trimming mechanism includes moving sword, stationary knife and drive mechanism, drive mechanism includes first spiral bevel gear pair, vertical axis, second spiral bevel gear pair, thread trimming camshaft, cam, thread trimming electro-magnet, pendulum rod, track, slider, the vertical axis is connected in the main shaft transmission, the thread trimming camshaft is connected in the vertical axis transmission, thread trimming camshaft fixed connection is along with the line trimming cam who changes, thread trimming camshaft one side is equipped with fixed thread trimming electro-magnet, thread trimming drive shaft one end of thread trimming electro-magnet is connected reset spring, and radially be equipped with the gyro wheel; when the electromagnet is electrified and attracted, the cylindrical surface of the roller keeps contact with the cam surface of the trimming cam, and the trimming driving shaft forms axial reciprocating motion when rotating along with the cam surface of the trimming cam, and the movable knife and the fixed knife form trimming during reciprocating motion. The structure is simple, the size is small, and the installation and the use are easy.

Description

Thread cutting mechanism of zigzag sewing machine

Technical Field

The utility model relates to a sewing machine field is a tortuous sewing machine thread trimming mechanism.

Background

The zigzag sewing machine is a special sewing machine, also called zigzag sewing machine or zigzag sewing, is used for zigzag sewing with certain elastic stitches, and is suitable for common cloth, leather, woolen cloth and the like. Two point machines (304 lock stitch) and three point machines (308 lock stitch) are commonly used. In general, a zigzag sewing machine can set straight lines, two points and other sewing stitches on one sewing machine, so that different requirements of users are met. The existing zigzag sewing machine generally comprises four parts, namely a machine head, a base, a transmission mechanism and accessories, wherein the machine head is the main part of the zigzag sewing machine and comprises four mechanisms of material needling, thread hooking, thread picking and feeding and auxiliary mechanisms of wire winding, material pressing, tooth falling and the like, and the mechanisms are reasonably matched in motion and work circularly to sew up sewing materials. The conventional zigzag sewing machine does not have a thread cutting function generally, and a worker needs to cut off the upper thread and the bottom thread of a sewing product by using scissors after sewing, so that the sewing efficiency is low, and a long thread end is wasted. In order to solve the above problem, some sewing machines with automatic thread trimming function are disclosed in the prior art, such as the publication No. CN212077316U published in chinese patent literature, the publication No. 2020, 12, month, and 4, the utility model is named as "thread trimming device of zigzag sewing machine", which mainly provides a structure for improving thread trimming capability by means of a spring, and although thread trimming operation can be realized, the stability of the spring force of the spring is not good enough, and once the spring fails, reliable thread trimming cannot be realized with long-term use, and use is affected. Therefore, the thread cutting structure of the existing zigzag sewing machine needs to be improved.

Disclosure of Invention

In order to overcome the defects, the utility model aims to provide a zigzag sewing machine thread trimming mechanism to the field, which solves the technical problems of complex thread trimming structure, poor thread trimming reliability and stability of the existing similar sewing machine. The purpose is realized by the following technical scheme.

A thread trimming mechanism of a zigzag sewing machine is arranged on a zigzag sewing machine body, the zigzag sewing machine body comprises a machine shell, a base, a motor and a main shaft, and the thread trimming mechanism comprises a movable cutter, a fixed cutter and a transmission mechanism which are positioned below a needle plate in the base and used for trimming threads; the transmission mechanism comprises a first spiral bevel gear pair, a vertical shaft, a second spiral bevel gear pair, a trimming cam shaft, a trimming cam, a trimming electromagnet, a swing rod, a track and a slide block, wherein one spiral bevel gear of the first spiral bevel gear pair is fixed with the main shaft, the other spiral bevel gear of the first spiral bevel gear pair is fixedly connected with one end of the vertical shaft, the vertical shaft rotates in a positioning manner relative to the shell, the other end of the vertical shaft extends into the base and is fixed with one spiral bevel gear of the second spiral bevel gear pair, the other spiral bevel gear of the second spiral bevel gear pair is fixedly connected with the trimming cam shaft, the trimming cam shaft rotates in a positioning manner relative to the base and is fixedly connected with the rotating trimming cam, the trimming electromagnet fixed relative to the base is arranged on one side of the trimming cam shaft in the base, a roller wheel rotating in a positioning manner is radially arranged on a shaft section at one end of the trimming drive shaft of the trimming electromagnet, the end of the trimming drive shaft is connected with a reset spring, and the reset spring is fixed relative to the base; the trimming electromagnet is not attracted in an initial state, when the electromagnet is electrified and attracted, the cylindrical surface of the roller keeps contact with the cam surface of the trimming cam, and when the roller rotates along with the trimming cam, the trimming driving shaft forms axial reciprocating motion; one end of the swing rod is positioned in the base and rotates, the middle of the swing rod is in linkage connection with the end part of the trimming drive shaft of the trimming electromagnet, and the swing rod forms swing rotation when reciprocating along with the trimming drive shaft; the rail is fixed in the base, the sliding block is matched with the rail, the rail is fixedly connected with the fixed cutter, the sliding block is fixedly connected with the movable cutter, the swinging end of the swinging rod is in linkage connection with the sliding block, namely the sliding block forms reciprocating sliding along the rail when swinging along with the swinging rod, and the movable cutter and the fixed cutter form trimming when reciprocating sliding. Through the structure, the main shaft is used as the power of the thread trimming mechanism, so that the effective thread trimming capacity is met, the thread trimming cam shaft is linked with the electromagnet, the thread trimming electromagnet only provides the movable cutter starting force, and the thread trimming force is not required to be provided, so that the power requirement of the thread trimming electromagnet is not high, and the cost is relatively low; the thread trimming cam shaft is utilized to drive the thread trimming driving shaft to realize the reciprocating motion of the movable cutter, the structure is relatively simple, the whole size is small, the installation and the use are easy, and the trend requirements of miniaturization and lightness of the sewing machine are met.

The linkage structure of the trimming drive shaft and the oscillating bar is as follows: the end part of the trimming drive shaft is fixedly connected with a joint with a fork opening, and a rod part of the swing rod is provided with a first roller which is in sliding fit with the fork opening. Through the structure, the linkage structure is flexible, the friction resistance is small, and the work is more reliable and stable.

The swing end of the swing rod and the sliding block are in linkage structure: the sliding block is fixedly connected with a bracket connected with the second roller, and the swinging end of the swinging rod is provided with a kidney-shaped groove in sliding fit with the second roller. By the structure, the stability and the reliability of linkage are also improved.

The utility model discloses overall structure is comparatively compact, can realize reliable, stable trimming operation, is fit for as all kinds of sewing machines, and especially tortuous sewing machine's trimming mechanism uses, or like product institutional advancement.

Drawings

FIG. 1 shows a main body structure of a sewing machine of the present invention.

Fig. 2 is a first schematic structural diagram of the present invention.

Fig. 3 is a schematic structural diagram of the present invention.

Fig. 4 is a third schematic structural diagram of the present invention.

Fig. 5 is a schematic diagram of the local explosion structure of the present invention.

The sequence numbers and names in the figure are: 1. the device comprises a machine shell, 2, a base, 3, a motor, 4, a main shaft, 5, a movable cutter, 6, a fixed cutter, 7, a first spiral bevel gear pair, 8, a vertical shaft, 9, a second spiral bevel gear pair, 10, a trimming cam shaft, 11, a trimming cam, 12, a trimming electromagnet, 1201, a trimming driving shaft, 13, a roller, 14, a rail, 15, a sliding block, 16, a fixing plate, 17, a joint, 1701, a fork opening, 18, a swing rod, 1801, a first roller, 1802, a kidney-shaped groove, 19, a bracket, 1901, a second roller, 20, a return spring, 21, a hinge pin, 22 and a support.

Detailed Description

The invention will now be further described with reference to the accompanying drawings.

As shown in fig. 1-5, the thread cutting mechanism is mounted on a zigzag sewing machine body, the zigzag sewing machine body comprises a machine shell 1, a base 2, a motor 3 and a main shaft 4, and the main shaft is driven by the motor and positioned in the machine shell. The thread cutting mechanism comprises a movable cutter 5, a fixed cutter 6 and a transmission mechanism which are positioned below the needle plate in the base and used for cutting threads. The transmission mechanism comprises a first spiral bevel gear pair 7, a vertical shaft 8, a second spiral bevel gear pair 9, a trimming cam shaft 10, a trimming cam 11, a trimming electromagnet 12, a swing rod 18, a track 14 and a slide block 15, wherein one spiral bevel gear of the first spiral bevel gear pair is fixed with the main shaft through a radial screw, the other spiral bevel gear of the first spiral bevel gear pair is fixedly connected with one end of the vertical shaft positioned in the machine shell through the radial screw, the main shaft and the vertical shaft are in right-angle transmission, and the vertical shaft is in positioning rotation relative to the machine shell. The other end of the vertical shaft extends into the base and is fixed with one spiral bevel gear of the second spiral bevel gear pair through a radial screw, the other spiral bevel gear of the second spiral bevel gear pair is fixedly connected with one end of a trimming cam shaft through the radial screw, the trimming cam shaft rotates in a positioning mode relative to the base, and the trimming cam shaft is fixedly connected with a trimming cam rotating along with the trimming cam.

A trimming electromagnet 12 is arranged on one side of the trimming cam shaft 10 in the base 2 and is fixed in the base through a fixing plate 16. The axial section of one end of the trimming drive shaft 1201 of the trimming electromagnet is axially connected with a roller 13 which is positioned and rotated, the end of the trimming drive shaft is fixedly connected with a return spring 20, and the return spring is fixed on the base. When the electromagnet is electrified and attracted, the cylindrical surface of the roller is kept in contact with the cam surface of the trimming cam, and the roller is pushed by the cam surface to drive the trimming driving shaft to axially reciprocate along with the rotation of the trimming cam.

One end of the swing rod 18 is positioned on a support 22 through a hinge pin 21 to rotate, and the support is fixed in the base. The middle part of pendulum rod is connected with the trimming drive shaft 1201 tip linkage of trimming electro-magnet 12, and the linkage structure is: the end part of the thread cutting driving shaft is fixedly connected with a joint 17 connected with a fork mouth 1701, and the rod part of the swing rod is provided with a first roller 1801 in sliding fit with the fork mouth, namely the swing rod forms swing rotation when reciprocating along with the thread cutting driving shaft. Above-mentioned track 14 is straight line track and in being fixed in base 2 through the screw, above-mentioned slider 15 and track sliding fit, and the track tip passes through stationary knife leg joint stationary knife 6, and the slider tip moves sword 5 through moving the sword leg joint, and the swing end and the slider linkage of pendulum rod are connected, and the linkage structure is: the sliding block is fixedly connected with a bracket 19 connected with a second roller 1901, a kidney-shaped groove 1802 in sliding fit with the second roller is arranged at the swinging end of the swinging rod, namely the sliding block forms reciprocating sliding along the track when swinging along with the swinging rod, and the movable knife and the fixed knife form a trimming line when reciprocating sliding.

The above contents are intended to illustrate the technical means of the present invention, and do not limit the technical scope of the present invention. Obvious modifications or substitutions by one skilled in the art can be made in the light of the present disclosure, and are within the scope of the appended claims.

Claims (3)

1. A thread cutting mechanism of a zigzag sewing machine is arranged on a zigzag sewing machine body, the zigzag sewing machine body comprises a machine shell (1), a base (2), a motor (3) and a main shaft (4), and the thread cutting mechanism comprises a movable cutter (5), a fixed cutter (6) and a transmission mechanism, wherein the movable cutter is positioned below a needle plate in the base and used for cutting threads; the transmission mechanism is characterized by comprising a first spiral bevel gear pair (7), a vertical shaft (8), a second spiral bevel gear pair (9), a trimming cam shaft (10), a trimming cam (11), a trimming electromagnet (12), a swing rod (18), a track (14) and a sliding block (15), wherein one spiral bevel gear of the first spiral bevel gear pair is fixed with the main shaft (4), the other spiral bevel gear is fixedly connected with one end of the vertical shaft, the vertical shaft rotates in a positioning manner relative to the machine shell (1), the other end of the vertical shaft extends into the base (2) and is fixed with one spiral bevel gear of the second spiral bevel gear pair, the other spiral bevel gear of the second spiral bevel gear pair is fixedly connected with the trimming cam shaft, the trimming cam shaft rotates in a positioning manner relative to the base and is fixedly connected with the trimming cam (11) rotating along with the direction, the trimming electromagnet fixed relative to the base is arranged on one side of the trimming cam shaft in the base, a shaft section at one end of the trimming drive shaft (1201) of the trimming electromagnet is radially provided with a positioning rotation roller (20), and the reset spring is connected with the reset spring; the trimming electromagnet is not attracted in an initial state, when the electromagnet is electrified and attracted, the cylindrical surface of the roller keeps contact with the cam surface of the trimming cam, and when the roller rotates along with the trimming cam, the trimming driving shaft forms axial reciprocating motion; one end of the swing rod is positioned in the base and rotates, the middle part of the swing rod is in linkage connection with the end part of the trimming driving shaft of the trimming electromagnet, and the swing rod swings and rotates along with the trimming driving shaft when reciprocating; the rail is fixed in the base, the sliding block is matched with the rail, the rail is fixedly connected with the fixed cutter (6), the sliding block is fixedly connected with the movable cutter (5), the swinging end of the swinging rod is in linkage connection with the sliding block, namely the sliding block forms reciprocating sliding along the rail when swinging along with the swinging rod, and the movable cutter and the fixed cutter form a trimming line when the sliding block slides in a reciprocating mode.

2. The zigzag sewing machine thread trimming mechanism according to claim 1, wherein the linkage structure of the thread trimming driving shaft (1201) and the swing link (18) is: the end part of the trimming drive shaft is fixedly connected with a joint (17) connected with a fork opening (1701), and a rod part of the swing rod is provided with a first roller (1801) in sliding fit with the fork opening.

3. The zigzag sewing machine thread trimming mechanism according to claim 1, wherein the oscillating end of the oscillating lever (18) and the slider (15) are linked in a structure that: the sliding block is fixedly connected with a bracket (19) of a second roller (1901), and a kidney-shaped groove (1802) in sliding fit with the second roller is formed in the swinging end of the swinging rod.

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