WO2021169182A1

WO2021169182A1 - Sewing machine

Info

Publication number: WO2021169182A1
Application number: PCT/CN2020/107005
Authority: WO
Inventors: 黄林炜; 管建平; 林晓晓
Original assignee: 杰克缝纫机股份有限公司
Priority date: 2020-02-25
Filing date: 2020-08-05
Publication date: 2021-09-02
Also published as: CN111118752B; CN111118752A

Abstract

A sewing machine, comprising a presser foot connecting rod (32, 77) and a swing plate seat (10, 69), and further comprises a cam crank (3, 65) and a crank driving device (1, 61) used for driving the cam crank to rotate around a cam rotating center on the cam crank. The cam crank is connected to an output end of the crank driving device; the cam crank comprises a presser foot adjusting part and a plate seat adjusting part; in a presser foot mode, the cam crank rotates and drives the presser foot connecting rod to move by means of the presser foot adjusting part; in a needle pitch adjusting mode, the cam crank rotates and pushes the swing plate seat to move by means of the plate seat adjusting part. Different parts on the cam crank are adopted to drive the presser foot connecting rod and the swing plate seat respectively, the functions of automatic backstitch, automatic dense seam and automatic presser foot can be achieved only by providing one crank driving device, the needle pitch can be adjusted, a backstitch electromagnet, a dense seam electromagnet and a presser foot electromagnet can be omitted, and the occupied space of the sewing machine can be saved.

Description

Sewing machine

This application claims the priority of a Chinese patent application filed with the Chinese Patent Office with an application number of 202010118064.7 and an invention title of "sewing machine" on February 25, 2020, the entire content of which is incorporated into this application by reference.

Technical field

The invention relates to the field of clothing equipment manufacturing, in particular to a sewing machine.

Background technique

In the existing sewing machines, in order to realize the functions of automatic reverse stitching, automatic dense stitching and automatic presser foot lifting, the reverse stitching electromagnet drives the swinging plate seat, the dense stitching electromagnet drives the swinging plate seat, and the presser foot lifting electromagnet respectively. The presser foot lifting link is realized, and the sewing machine occupies a large space due to the need to set up three sets of driving equipment.

Therefore, how to reduce the space occupied by the sewing machine is a technical problem that needs to be solved by those skilled in the art.

Summary of the invention

In view of this, the object of the present invention is to provide a sewing machine which occupies a relatively small space.

In order to achieve the above objectives, the present invention provides the following technical solutions:

A sewing machine includes a presser foot connecting rod and a swing plate seat; also includes a cam crank and a crank drive device for driving the cam crank to rotate about the upper cam rotation center, the cam crank is connected to the crank drive device The output end of the cam crank includes a presser foot adjusting portion and a plate seat adjusting portion;

In the presser foot lifting mode, the cam crank rotates and drives the presser foot lifting link to move through the presser foot adjusting part;

In the stitch length adjustment mode, the cam crank rotates and pushes the swing plate base to move through the plate base adjusting portion.

Preferably, the plate seat adjusting portion includes a needle distance adjusting surface provided on the outer peripheral surface of the cam crank, the needle distance adjusting surface is supported under the needle distance adjusting pin on the swing plate seat, the The needle length adjusting surface includes a driving surface, the driving surface being a diameter-reducing arc surface relative to the cam rotation center; in the needle length adjusting mode, the driving surface pushes the needle length adjusting pin to move.

Preferably, the driving surface is a gradually increasing distance from the cam rotation center along a circumferential direction.

Preferably, the needle length adjusting surface further includes a holding surface abutting on the circumferential direction of the driving surface, and the holding surface is an equal-diameter arc surface with respect to the cam rotation center; in the presser foot lifting mode , The holding surface slides relative to the needle pitch adjusting pin and the swing plate seat remains stationary.

Preferably, an elastic reset member is connected to the swing plate seat, and the elastic reset member keeps the needle length adjusting pin pressed against the needle length adjusting surface.

Preferably, the presser foot adjusting portion includes a presser foot hole penetrating through the cam crank in an axial direction, and a presser foot pin on the presser foot connecting rod is movably inserted into the presser foot In the presser foot lifting mode, the hole wall of the presser foot lifting hole abuts against the presser foot lifting pin and drives the presser foot lifting pin; in the stitch length adjustment mode, the lifting The presser foot hole moves relative to the presser foot lifting pin and the presser foot lifting pin remains stationary.

Preferably, the presser foot lifting hole is an arc-shaped hole, and the presser foot lifting hole is an equal-diameter arc with respect to the rotation center of the cam.

Preferably, the presser foot lifting adjusting portion includes a presser foot lifting driving surface provided on the outer peripheral surface of the cam crank, the presser foot lifting link is rotatably connected to a presser foot lifting driving plate, and the presser foot lifting driving plate It is rotatably connected to the casing, and the presser foot lifting drive plate is provided with a presser foot lifting drive pin;

In the presser foot lifting mode, the cam crank rotates and drives the presser foot lifting drive plate to rotate through the contact between the presser foot drive pin and the presser foot drive surface.

Preferably, the plate seat adjusting portion includes a protruding pin fixed on the cam crank, the swing plate seat is hinged to a needle length adjusting crank through a needle length connecting rod, and the needle distance adjusting crank is rotatably connected to the A casing, a sliding groove is provided on the needle pitch adjusting crank, and the protruding pin is movably inserted into the sliding groove;

In the stitch length adjustment mode, the cam crank rotates and drives the stitch length adjustment crank to rotate through the sliding groove, and the presser foot lifting driving pin is separated from the presser foot lifting driving surface;

In the presser foot lifting mode, the protruding pin moves in the sliding groove and the stitch length adjusting crank remains stationary.

Preferably, a support is fixed on the casing, a limit damping block is provided on the support, and an elastic reset member is connected between the swing plate seat and the support; in the presser foot lifting mode Next, the elastic reset member tightens the needle distance seat against the limit shock-absorbing block.

The sewing machine provided by the present invention includes a presser foot connecting rod and a swing plate seat; it also includes a cam crank and a crank driving device for driving the cam crank to rotate around the upper cam rotation center, and the cam crank is connected to the output end of the crank driving device, The cam crank includes a presser foot adjusting part and a plate seat adjusting part; in the presser foot lifting mode, the cam crank rotates and the presser foot adjusting part drives the presser foot lifting link to move; in the stitch length adjustment mode, the cam crank rotates and The swing plate seat is pushed to move through the plate seat adjustment part.

Different parts of the cam crank are used to drive the presser foot connecting rod and the swinging plate seat respectively. Only one crank drive device can realize the functions of automatic reverse stitching, automatic dense stitching and automatic presser foot lifting, as well as needle alignment. The adjustment of the distance can cancel the setting of the reverse stitching electromagnet, the dense stitching electromagnet, and the presser foot lifting electromagnet, which can save the space of the sewing machine and reduce the cost. In addition, the height of the presser foot, the forward and reverse stitching, the dense stitch and the needle The distance can be adjusted in real time, which is easy to use.

Description of the drawings

In order to explain the embodiments of the present invention or the technical solutions in the prior art more clearly, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only It is an embodiment of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on the provided drawings without creative work.

Figure 1 is a structural diagram of a specific embodiment of a sewing machine provided by the present invention;

Figure 2 is a first partial structural diagram of the first embodiment of the sewing machine provided by the present invention;

Figure 3 is a second partial structural diagram of the first embodiment of the sewing machine provided by the present invention;

4 is a third partial structural diagram of the first embodiment of the sewing machine provided by the present invention;

Figure 5 is a structural diagram of the first cam crank part of the sewing machine provided by the present invention when the needle pitch adjusting pin is located on the driving surface. The dashed line indicates the range of the driving surface and the holding surface, and the arc-shaped solid arrow indicates the forward direction. Hour hand direction

Figure 6 is a structural diagram of the first cam crank part of the sewing machine provided by the present invention when the stitch length adjusting pin just enters the holding surface. The dotted line indicates the center line of the presser foot lifting hole in the radial direction, and the dotted line indicates The range of the driving surface and the holding surface, the arc-shaped solid arrow indicates the clockwise direction;

7 is a structural diagram of the first cam crank part in the presser foot lifting mode of the sewing machine provided by the present invention. The dotted line indicates the range of the driving surface and the holding surface, and the arc-shaped solid arrow indicates the clockwise direction;

Figure 8 is a first structural diagram of the second embodiment of the sewing machine provided by the present invention;

Figure 9 is a second structural diagram of the second embodiment of the sewing machine provided by the present invention;

Figure 10 is a third structural diagram of the second embodiment of the sewing machine provided by the present invention

11 is a structural diagram of the second cam crank in the second embodiment of the sewing machine provided by the present invention;

Figure 12 is a structural diagram of a needle pitch adjusting crank in the second embodiment of the sewing machine provided by the present invention;

Fig. 13 is an assembly view of the needle pitch adjusting crank and the second cam crank in the second embodiment of the sewing machine provided by the present invention, and the dotted line is a perspective part.

Reference signs:

The first crank driving device 1, the first lifting shaft 2, the first cam crank 3, the stitch length adjusting surface 3-1, the driving surface 3-11, the holding surface 3-12, the cam rotation center 3-2, the presser foot lifting Hole 3-3, Thread Lifting Crank 4, Thread Lifting Axis Screw 5, Needle Pitch Adjustment Pin 6, First Plate Base Axis Pin 7, Thread Lifting Link 8, Second Plate Base Axis Pin 9, First Swing Plate base 10, first mounting fixing hole 10-1, first mounting fixing hole 10-2, feeding link 11, first feeding eccentric wheel 12, tooth lifting eccentric wheel 13, presser foot lifting axis screw 14, lifting pressure Rear foot lever 15, rear lever axis screw 16, first presser foot lift lever 17, presser foot front lever 18, presser foot front lever 19, first presser bar guide 20, presser lower bushing 21, thread The frame assembly 22, the first presser foot 23, the teeth 24, the first sliding block 25, the fork crank 26, the needle plate screw 27, the first needle plate 28, the first pressing rod 29, the first feeding shaft 30, the first A main shaft 31, a first presser foot lifting connecting rod 32, a feeding crank 33, a fixed plate 35, a tension spring 36, a spring connecting pin 37, and a presser foot lifting pin 38;

The second housing 41, the second main shaft 42, the second feeding eccentric 43, the feeding connecting rod assembly 44, the crankshaft 45 after feeding, the second feeding shaft 46, the bracket seat 47, the bracket 48, the feeding dog 49, the first The second needle plate 50, the second sliding block 51, the fork 52, the second lifting shaft 53, the second pressing foot 54, the second pressing rod 55, the pressing rod sleeve 56, the second pressing rod guide 57, the lifting plate 58 , Front lever 59, second presser foot lifting rod 60, second crank driving device 61, stitch length adjusting crank 64, sliding groove 64-1, second cam crank 65, presser foot lifting driving surface 65-1, raised pin 65-2, rear lever 66, fulcrum pin 67, stitch length connecting rod 68, second swing plate base 69, third plate base axis pin 69-1, contact surface 69-2, plate base hook 69-3, support The seat 70, the support hook 70-1, the limit shock absorber 70-2, the spring 71, the roller 73, the presser foot driving plate 74, the pin 75, the second presser foot connecting rod 77, and the shaft sleeve 78.

Detailed ways

The technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative work shall fall within the protection scope of the present invention.

The core of the present invention is to provide a sewing machine, which occupies a relatively small space.

It should be noted that when an element is referred to as being "fixed to" another element, it can be directly on the other element or a central element may also be present. When an element is considered to be "connected" to another element, it can be directly connected to the other element or an intermediate element may be present at the same time. In addition, the terms "first" and "second" are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance.

In a specific embodiment of the sewing machine provided by the present invention, the sewing machine includes a first swinging plate base 10, which is connected to the first main shaft 31 and the first feeding shaft 30 through a plate base transmission assembly, so as to adjust the first The relative position of the swing plate base 10 itself realizes the functions of adjusting the stitch length, reverse stitching, and dense stitching. Specifically, the plate seat transmission assembly includes a first feeding eccentric 12, a first plate seat axis pin 7, a second plate seat axis pin 9, a feeding crank 33 and other components. As shown in Figures 1 and 3, a first main shaft 31 is installed on the first housing of the sewing machine. The first main shaft 31 rotates around an axis, and a first feeding eccentric 12 is installed on the first main shaft 31. And lift the eccentric wheel 13. The first feeding eccentric 12 is connected to the first swinging plate base 10 through the feeding connecting rod 11. The first swinging plate base 10 is provided with a first mounting fixing hole 10-1 and a first mounting fixing hole 10-2. The hole 10-1 and the first mounting fixing hole 10-2 are arranged coaxially, and these two holes are respectively connected to the first casing through the first plate base axis pin 7 and the second plate base axis pin 9 respectively. The first swing plate base 10 is connected to the first feeding shaft 30 through a feeding crank 33, and a tooth frame assembly 22 is installed on the other end of the first feeding shaft 30. The tooth-lifting eccentric 13 is connected to the tooth-lifting crank 4 through the tooth-lifting connecting rod 8. There is a tooth-lifting axial screw 5 between the tooth-lifting connecting rod 8 and the tooth-lifting crank 4, which can realize the tooth-lifting connecting rod 8 and the tooth-lifting crank 4 During the mutual swing action, the tooth-lifting crank 4 is fixed on the first tooth-lifting shaft 2, and the other end of the first tooth-lifting shaft 2 is equipped with a tooth-lifting fork-shaped crank 26, the tooth-lifting fork-shaped crank 26 and the tooth frame assembly 22 The first sliding block 25 on the upper part is connected, and the first sliding part 25 on the bracket assembly 22 can slide in the fork-shaped groove 26-1 of the fork-shaped crank 26.

The sewing machine further includes a first presser foot lifting link 32, which is connected to the first presser foot 23 through a presser foot lifting transmission assembly to realize the presser foot lifting operation. Specifically, as shown in Figure 1, the presser foot lifting transmission assembly includes a presser bar lower bushing 21, a first presser bar 29, a first presser bar guide 20, a presser foot front pull rod 19, a presser foot front lever 18, and a first presser foot Presser foot lifting lever 17, presser foot rear lever 15, presser foot shaft position screw 14. The lower bushing 21 of the pressing rod is fixed on the first casing. The first pressing rod 29 passes through the lower bushing 21 of the pressing rod and can move up and down. The lower end of the first pressing rod 29 is equipped with a first pressing foot 23. The presser foot 23 can be in contact with the teeth 24 and the first needle plate 28. A first pressure bar guide 20 is installed on the upper end of the first pressure rod 29. The first pressure rod guide 20 cooperates with the presser foot lifting front rod 19, and the presser foot front rod 19 drives the first pressure rod guide 20 to move up and down. . The presser foot front lever 18 is connected to the presser foot rear lever 15 through the first presser foot lift rod 17, and the presser foot rear lever 15 is fixed to the first housing by the rear lever shaft screw 16. After the presser foot is lifted The lever 15 can be rotated around the rear lever axis screw 16. The first presser foot lifting link 32 and the presser foot rear lever 15 are provided with a presser foot lifting axis screw 14, and the first presser foot lifting link 32 can be wound around The presser foot lifting axis screw 14 rotates and axially shifts. In addition, the sewing machine is provided with a first needle plate 28. The first needle plate 28 is fixed on the first machine casing by a needle plate screw 27. There are several tooth grooves on the first needle plate 28, and the teeth on the tooth frame assembly 22 24 can pass through this tooth socket.

The sewing machine also includes a first cam crank 3 and a first crank driving device 1 for driving the first cam crank 3 to rotate around the cam rotation center 3-2 on the first cam crank 3. The housing of the first crank drive device 1 may be specifically fixed on the first housing of the sewing machine. Preferably, as shown in FIG. 1, the first crank driving device 1 is a stepping motor. Of course, in other embodiments, the first crank drive device 1 may also be an electromagnet or other motors.

The first cam crank 3 is connected to the output end of the first crank driving device 1, and the first cam crank 3 includes a presser foot adjusting part and a plate seat adjusting part. In the presser foot lifting mode, the first cam crank 3 rotates and drives the first presser foot lifting link 32 to move through the presser foot adjusting part. In the stitch length adjustment mode, the first cam crank 3 rotates and pushes the first swing plate base 10 to move through the plate base adjusting portion.

In this embodiment, different parts on the first cam crank 3 are used to drive the first presser foot lifting link 32 and the first swing plate base 10 respectively, and only one first crank drive device 1 is needed to realize automatic inversion. The functions of sewing, automatic encryption sewing and automatic presser foot lifting can also realize the adjustment of the stitch length. The settings of reverse sewing electromagnet, encryption sewing electromagnet and presser foot lifting electromagnet can be cancelled, which can save the space occupied by the sewing machine. Reduce costs. In addition, the height of the presser foot, front and back stitching, dense stitching and stitch length can be adjusted in real time, which is easy to use.

Further, referring to FIGS. 3 and 5, the plate seat adjusting portion includes a needle length adjusting surface 3-1 provided on the outer peripheral surface of the first cam crank 3. The needle length adjusting surface 3-1 is supported on the first swing plate seat 10 on the stitch length adjustment pin 6 below. As shown in Figure 5, the stitch length adjusting pin 6 contacts and presses on the stitch length adjusting surface 3-1. The needle-pitch adjusting surface 3-1 includes a driving surface 3-11. The driving surface 3-11 is a reduced-diameter arc surface with respect to the cam rotation center 3-2, that is, the points on the driving surface 3-11 and the cam rotation center 3- The spacing between 2 is not exactly the same. Among them, the stitch length adjusting pin 6 can be fixedly arranged on the first swinging plate base 10, or it can be rotatably connected to the pin mounting hole of the first swinging plate base 10. In addition, the stitch length adjusting pin 6 is on the first swinging plate base 10. The position set above is not specifically limited. It only needs to be able to drive the first swing plate base 10 to move. The stitch length adjustment pin 6 is usually different from the first plate base axis pin 7 and the second plate base axis pin 9 String. In the stitch length adjustment mode, the driving surface 3-11 pushes the stitch length adjustment pin 6 to move, and the movement of the stitch length adjustment pin 6 will drive the first swing plate base 10 around the first plate base axis pin 7 and the second plate base axis position The pin 9 swings to realize the adjustment of reverse stitching, dense stitching and the size of the stitch length. The driving surface 3-11 is directly arranged on the outer peripheral surface of the first cam crank 3 to adjust the movement of the first swing plate base 10, which is convenient for processing.

Among them, preferably, the driving surface 3-11 is a gradual arc surface with a gradually increasing distance from the cam rotation center 3-2 along one direction in the circumferential direction. As shown in the embodiment shown in Fig. 5, along the clockwise direction in the circumferential direction, the distance between the points on the driving surface 3-11 and the cam rotation center 3-2 gradually increases. Of course, in other embodiments, the distance between the points on the driving surface 3-11 and the cam rotation center 3-2 may gradually increase in the counterclockwise direction along the circumferential direction. Through the setting of the gradual arc surface, the position adjustment of the driving surface 3-11 to the needle pitch adjusting pin 6 can be more regular.

Further, the needle-pitch adjusting surface 3-1 also includes a holding surface 3-12 abutting on the circumferential side of the driving surface 3-11, and the holding surface 3-12 is an equal-diameter arc surface with respect to the cam rotation center 3-2. In the presser foot lifting mode, the holding surface 3-12 slides relative to the stitch length adjusting pin 6 and the first swing plate base 10 remains stationary. As shown in Figure 7, a holding surface 3-12 is provided on one side of the driving surface 3-11 in the counterclockwise direction. In the presser foot lifting mode, the first crank driving device 1 drives the first cam crank 3 to rotate. , The stitch length adjusting pin 6 is always located on the holding surface 3-12, so as to ensure that the position of the first swinging plate base 10 remains unchanged, and avoiding unnecessary movement of the first swinging plate base 10 and the plate base transmission assembly during the process of lifting the presser foot. Thereby reducing unnecessary energy consumption.

Further, the first swing plate base 10 is connected with an elastic reset member, and the elastic reset member keeps the stitch length adjusting pin 6 pressed against the stitch length adjusting surface 3-1. As shown in Figures 2 and 3, the elastic return member is a tension spring 36, one end of the elastic return member is connected to the spring connecting pin 37 fixedly arranged on the first swing plate base 10, and the other end is connected to the first housing of the sewing machine On the fixed plate 35, the first swinging plate seat 10 is always subjected to the pulling force of the tension spring 36, so that the first swinging plate seat 10 is in a stable position and can always be attached to the needle pitch adjusting surface 3-1. The plate base 10 is completely driven by the needle-pitch adjusting surface 3-1. Compared with the first swing plate base 10 that only relies on gravity to press on the needle-pitch adjusting surface 3-1, the adjustment accuracy is higher. In addition, because the first cam crank 3 and the stitch length adjusting pin 6 can always keep in contact, there will be no repeated separation and re-contact during operation, thus avoiding the noise generated by the impact during the re-contact process, and achieving no reverse seam noise.

Further, referring to FIG. 4, the presser foot adjusting portion includes a presser foot hole 3-3 which penetrates through the first cam crank 3 in the axial direction, and a presser foot pin 38 on the first presser foot connecting rod 32 It can be movably inserted into the presser foot hole 3-3. Wherein, the presser foot lifting pin 38 may be rotatably connected to the socket of the first presser foot lifting link 32, and may also be fixedly connected to the first presser foot lifting link 32. In the presser foot lifting mode, the hole wall of the presser foot hole 3-3 abuts against the presser foot pin 38 and drives the presser foot pin 38. In the stitch length adjustment mode, the presser foot lifter hole 3-3 moves relative to the presser foot lifter pin 38 and the presser foot lifter pin 38 remains stationary, that is, the hole wall of the presser foot lifter hole 3-3 has no effect on the presser foot lifter pin 38. Pressing force, the presser foot lifting hole 3-3 has a certain idle stroke relative to the presser foot lifting pin 38, and the presser foot lifting pin 38 is not driven. In the process of stitch length adjustment and reverse stitching, the first presser foot lifting link The position of the presser foot lifting pin 38 on 32 remains unchanged, that is, the presser foot lifting action is not performed.

Wherein, preferably, as shown in FIG. 6, the presser foot lifting hole 3-3 is an arc-shaped hole, and the presser foot lifting hole 3-3 is an equal-diameter arc with respect to the cam rotation center 3-2, specifically, the lifting The distance between each point on the center line S of the presser foot hole 3-3 in the radial direction and the cam rotation center 3-2 is the same. The presser foot lifting hole 3-3 is set as an arc-shaped hole, which is consistent with the shape of the motion path of the presser foot lifting hole 3-3 relative to the presser foot pin 38 when idling. During the assembly process, the presser foot hole 3- The positional relationship between 3 and the presser foot lifting pin 38 can provide a reference, which reduces the difficulty of assembling the first cam crank 3. Of course, in other embodiments, the presser foot lifting hole 3-3 can also be configured as a round hole or a hole structure of other shapes.

Further, referring to FIG. 2, the first presser foot lifting link 32 and the first swing plate seat 10 are respectively located on both sides of the first cam crank 3 in the axial direction, and the first cam crank 3 connects the first presser foot link 32 is separated from the first swing plate base 10 to avoid interference between the movement of the first presser foot lifting link 32 and the first swing plate base 10.

The working principle of the sewing machine provided in this embodiment for reverse stitching, dense stitching and presser foot lifting is as follows:

In the stitch length adjustment mode, the position of the first swing plate base 10 is adjusted by adjusting the angular position of the first cam crank 3, thereby changing the swing amplitude of the first feeding shaft 30 to achieve the purpose of adjusting the stitch length. As shown in Figure 5, the stepping motor rotates clockwise, and the needle pitch adjusting pin 6 is pushed up by the driving surface 3-11 and moves spatially under the drive of the driving surface 3-11. By controlling the rotation angle of the stepping motor, you can Adjust the stitch length. By adjusting the rotation direction of the stepping motor, the functions of sealing and reverse stitching can be realized. For example, clockwise rotation can realize forward stitching, and counterclockwise rotation can realize reverse stitching. In addition, the tension spring 36 always tightens the first swing plate base 10 so that the first swing plate base 10 is in a stable position. At the same time, in the stitch length adjustment mode, the presser foot pin 38 on the first presser foot link 32 moves in the presser foot hole 3-3 of the first cam crank 3, but the presser foot hole 3-3 The hole wall will not squeeze the presser foot pin 38, so the presser foot pin 38 will not be driven by the first cam crank 3. The presser foot hole 3-3 is equivalent to the empty stroke, therefore, during the stitch length adjustment process Although the position of the presser foot lifting hole 3-3 relative to the presser foot lifting pin 38 is changing, the position of the presser foot is not affected.

In the presser foot lifting mode, when the stitch length adjusting pin 6 on the first swinging plate base 10 moves to the holding surface 3-12, the rotation of the stepping motor does not affect the position of the first swinging plate base 10, and it cannot be adjusted at this time The size of the stitch length, the stitch length is at a stable value, and it will not switch between forward and backward stitching and encryption stitching. As shown in Figure 6, when the stitch length adjusting pin 6 moves from the driving surface 3-11 to the holding surface 3-12, the presser foot pin 38 and one end of the presser foot hole 3-3 on the first cam crank 3 Close, the first cam crank 3 continues to rotate clockwise, the first cam crank 3 will drive the first presser foot lifting link 32 to move, and the first presser foot lifting link 32 will drive the presser foot lifter lever 15 around the axis The pin 16 rotates, and the lever 15 drives the front lever 18 to move after the presser foot is lifted, and then adjusts the operating parameters such as the height of the first presser foot 23 to realize the presser foot lifting operation.

Obviously, in other embodiments, the arrangement of the presser foot adjusting portion and the plate seat adjusting portion is not limited to the manner provided in the foregoing embodiment.

In another specific embodiment, as shown in FIGS. 9 to 13, the sewing machine includes a second cam crank 65 and a second crank driving device 61 for driving the second cam crank 65 to rotate about its center of rotation. The second cam crank 65 is connected to the output end of the second crank driving device 61, and the second cam crank 65 includes a presser foot adjusting part and a plate seat adjusting part. In the presser foot lifting mode, the second cam crank 65 rotates and drives the second presser foot lifting link 77 to move through the presser foot lifting adjustment part; in the stitch length adjustment mode, the second cam crank 65 rotates and passes the plate seat adjustment part Push the second swing seat 69 to move.

The presser foot lifting adjusting part includes a presser foot lifting driving surface 65-1 provided on the outer peripheral surface of the second cam crank 65, and the second presser foot lifting link 77 is rotatably connected to the presser foot lifting driving plate 74. The presser foot lifting driving plate 74 is rotatably connected to the second casing 41, and specifically is rotatably connected to the pin 75 of the second casing 41. The presser foot drive plate 74 is provided with a presser foot drive pin. The presser foot drive pin is preferably a roller 73 rotatably connected to the drive plate. The presser foot drive surface 65-1 is preferably an arc surface. The presser foot lifting driving surface 65-1 rolls up, and there is no impact when the second presser foot 54 is raised and lowered, so the noise and crash problems of the current reverse stitching and presser foot lifting can be avoided. In the presser foot lifting mode, the second cam crank 65 rotates and contacts the presser foot lifting driving surface 65-1 through the presser foot lifting drive pin to drive the presser foot lifting driving plate 74 to rotate.

Wherein, the plate seat adjusting portion includes a raised pin 65-2 fixed on the second cam crank 65, the second swing plate seat 69 is hinged to the needle length adjusting crank 64 through the needle length connecting rod 68, and the needle length connecting rod 68 is specifically connected On the third plate seat axis pin 69-1 of the second swing plate seat 69. The second swing plate base 69 is installed on the fulcrum pin 67 on the second casing 41 and can rotate around the fulcrum pin 67. The angular position of the second oscillating plate seat 69 can control the oscillating amplitude of the crank randomizer operation after feeding, so as to control the stitch length of the sewing machine. The stitch length adjusting crank 64 is rotatably connected to the second casing 41. The needle pitch adjusting crank 64 is provided with a sliding groove 64-1, and the sliding groove 64-1 can penetrate the needle pitch adjusting crank 64 in an axial direction. The protruding pin 65-2 is movably inserted into the sliding groove 64-1. Among them, the stitch length adjusting crank 64 is specifically connected to the second casing 41 through a sleeve 78 to ensure smooth rotation.

In the stitch length adjustment mode, the second cam crank 65 rotates and drives the stitch length adjustment crank 64 to rotate through the sliding groove 64-1, and the presser foot lifting driving pin is separated from the presser foot lifting driving surface 65-1. In the presser foot lifting mode, the protruding pin 65-2 moves in the sliding groove 64-1 and the stitch length adjusting crank 64 remains stationary.

In this embodiment, by adding the stitch length adjusting crank 64 and the presser foot lifting drive plate 74 that are rotatably connected to the second casing 41 to realize the separate connection with the swing plate base and the presser foot connecting rod, there is no need to change the swing plate base and The existing structure and installation position of the presser foot connecting rod can be connected with the second cam crank 65 by setting the structure of the stitch length adjusting crank 64 and the presser foot driving plate 74; in addition, the stitch length adjustment mode is lifted. The presser foot connecting rod is not affected, and the swinging plate seat is not affected in the presser foot lifting mode, which can avoid the mutual influence or confusion between the stitch length adjustment process and the presser foot lifting process.

Further, a support 70 is fixed on the second housing 41, and a limit shock absorbing block 70-2 is provided on the support 70. An elastic return piece is connected between the second swing plate seat 69 and the support seat 70, such as a spring 71 as shown in FIG. 10. Among them, the second swinging plate base 69 is provided with a plate base hook 69-3, and the supporting base 70 is provided with a supporting hook 70-1, and both ends of the elastic reset member are respectively hung on the plate base hook 69-3 and the supporting hook. 70-1 on. The second oscillating plate base 69 and the stitch length adjusting crank 64 are respectively connected to the two ends of the stitch length connecting rod 68.

In the presser foot raising mode and the second crank drive device 61 is in the initial state of being de-energized and relaxed, the spring 71 pulls the second swing plate seat 69 against the support seat 70. By the second swinging plate seat 69 and the support 70 abutting, the second swinging plate seat 69 can be reliably limited to the initial position, and the position of the second swinging plate seat 69 remains unchanged during the process of lifting the presser foot. At the same time, since the spring 71 pulls the second swinging plate seat 69 against the limit damping block 70-2, it is possible to prevent the second swinging plate seat 69 from generating large impact noise with the support 70 during the resetting process.

In addition, in this embodiment, other structures are included in addition to the above structure. Wherein, a second main shaft 42 is installed on the second housing 41, a second feeding eccentric 43 is installed on the second main shaft 42, a feeding connecting rod assembly 44 is installed on the second feeding eccentric 43, and the feeding connecting rod assembly 44 is connected to the feeding On the rear crank, the crank after feeding is installed on the second feeding shaft 46, the second feeding shaft 46 is installed on the second housing 41, the front end of the second feeding shaft 46 is installed with a tooth frame seat 47, which is installed on the tooth frame seat 47 The tooth frame 48 is equipped with a feeding dog 49. The feeding dog 49 is located below the second needle plate 50 and can expose the upper plane of the second needle plate 50. The second needle plate 50 is installed on the second machine On the shell 41, a second sliding block 51 is installed at the other end of the bracket 48, and the second sliding block 51 is on the fork 52 to keep relative sliding between the two. The fork 52 is installed on the second lifting shaft 53, and the second lifting shaft 53 is installed on the second housing 41. The upper end of the feeding connecting rod is installed on the second feeding eccentric wheel 43.

In addition, one end of the second presser foot lifting link 77 is connected to the presser foot drive plate 74, and the other end is connected to the rear lever 66. The rear lever 66 is mounted on the second housing 41 and can rotate, and the other end of the rear lever 66 is connected to The second presser foot lifter rod 60, the other end of the second presser foot lifter rod 60 is connected to a front lever 59, the front lever 59 is mounted on the second housing 41 and can rotate, the front lever 59 is connected to the lifting plate 58, the lifting plate 58 Connected to the second pressure rod guide 57, the second pressure rod guide 57 is installed on the second pressure rod 55, the second pressure rod 55 is installed in the pressure rod sleeve 56, and the pressure rod sleeve 56 is installed on the second housing 41 On the upper side, a second pressing foot 54 is installed at the lower end of the second pressing rod 55, and the second pressing foot 54 is located above the second needle plate 50.

In the sewing machine provided by this embodiment, in the initial state, the protruding pin 65-2 abuts against the groove surface of the sliding groove 64-1 and the presser foot lifting driving surface 65-1 is in contact with the presser foot lifting driving pin. When the second cam crank 65 rotates in the first direction from the initial state position, it enters the presser foot lifting mode; when the second cam crank 65 rotates from the initial state position in the opposite direction of the first direction, it enters the stitch length adjustment mode.

For ease of understanding, the present invention regards the position of the stitch length of +5 as the initial position. The second crank drive device 61 and the second cam crank 65 installed on the second crank drive device 61 rotate clockwise. When the raised pin 65-2 on the cam crank 65 touches the lowest position of the sliding groove 64-1 on the stitch length adjusting crank 64, the second cam crank 65 drives the stitch length adjusting crank 64 and the stitch length connecting rod 68 to pull the second The swing plate seat 69 rotates upwards against the pulling force of the spring 71 and stops at a certain angular position to control the stitch length of the sewing machine. The second cam crank 65 rotates 27° clockwise from the initial position to the second crank driving device 61. Adjust the working range of the stitch length, the initial position of the stitch length is +5, when the second crank driving device 61 rotates 27° clockwise, the stitch length is adjusted from +5 to -5. According to the actual needs of the sewing machine working conditions, the second crank drive device 61 can be used to adjust the required stitch length in this interval, including the stitch length of normal sewing, the stitch length of reverse stitching, and the stitch length of close stitching (close to 0).

When the second crank driving device 61 is in the initial position, the roller 73 is in contact with the lowest position of the presser foot lifting driving surface 65-1 on the second cam crank 65. At this time, the second presser foot 54 is in a fully lowered state. When the stitch length needs to be adjusted, the roller 73 and the presser foot lifting driving surface 65-1 are in a disengaged state within the range of 0°-27° clockwise rotation of the second cam crank 65, so the adjustment of the stitch length will not affect To lift the presser foot.

When the sewing machine needs to lift the presser foot, the second crank driving device 61 and the second cam crank 65 rotate counterclockwise, and under the action of the spring 71, the second swinging plate seat 69 swings down until the contact surface 69 on the second swinging plate seat 69 -2 is in contact with the limit damping block 70-2. At this time, the sewing machine returns to the initial position. At the lowest position, when entering the idle stroke section of the chute 64-1, the roller 73 just touches the lowest position of the presser foot lifting driving surface 65-1 of the second cam crank 65. At this time, the second presser foot 54 is in a fully lowered state. The second crank driving device 61 and the second cam crank 65 continue to rotate, and the presser foot lifting driving surface 65-1 on the second cam crank 65 continues to raise the roller 73, pushing the presser foot lifting driving plate 74 to swing, and through the second cam crank 65 A series of transmissions from the presser foot lifting link 77 to the second presser rod 55 push the second presser foot 54 to be lifted, and the range of the second cam crank 65 rotating counterclockwise by 150° from the initial position is the working range of the presser foot. When the second cam crank 65 rotates counterclockwise by 150°, the roller 73 contacts the highest position of the presser foot lifting driving surface 65-1 of the second cam crank 65 to realize the presser foot lifting function.

In the range where the second cam crank 65 rotates 150° counterclockwise from the initial position, the raised pin 65-2 of the second cam crank 65 always moves in the sliding groove 64-1 of the needle pitch adjusting crank 64, which is an idle stroke , And will not drive the needle pitch adjustment crank 64 to rotate together.

In addition, when the sewing machine completes the presser foot lifting action and the second presser foot 54 is lowered, in order to ensure that the stitch length before and after the presser foot lifting action is consistent, the second crank driving device 61 will automatically rotate the raised pin 65-2 to the presser foot lifter The position set before the action.

The sewing machine in this embodiment, under the control of the motor and the controller program, can adjust the stitch length, dense stitch, reverse stitch, and lift the presser foot without impact, and can control the stitch length value and the height of the presser foot at random. The transmission efficiency, the precision of the mechanism and parts can also be realized.

The various embodiments in this specification are described in a progressive manner. Each embodiment focuses on the differences from other embodiments, and the same or similar parts between the various embodiments can be referred to each other.

The sewing machine provided by the present invention has been described in detail above. Specific examples are used in this article to illustrate the principle and implementation of the present invention. The description of the above examples is only used to help understand the method and core idea of the present invention. It should be pointed out that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and modifications can be made to the present invention, and these improvements and modifications also fall within the protection scope of the claims of the present invention.

Claims

A sewing machine includes a presser foot connecting rod and a swinging plate seat; it is characterized in that it also includes a cam crank and a crank drive device for driving the cam crank to rotate around the upper cam rotation center (3-2). The cam crank is connected to the output end of the crank drive device, and the cam crank includes a presser foot adjusting part and a plate seat adjusting part;

In the presser foot lifting mode, the cam crank rotates and drives the presser foot lifting link to move through the presser foot adjusting part;

In the stitch length adjustment mode, the cam crank rotates and pushes the swing plate base to move through the plate base adjusting portion.
The sewing machine according to claim 1, characterized in that the plate seat adjusting part includes a needle length adjusting surface (3-1) provided on the outer peripheral surface of the cam crank, and the needle length adjusting surface (3- 1) Supported under the needle pitch adjusting pin (6) on the swing plate seat, the needle pitch adjusting surface (3-1) includes a driving surface (3-11), and the driving surface (3-11) Relative to the cam rotation center (3-2), it is a diameter-changing arc surface; in the stitch length adjustment mode, the driving surface (3-11) pushes the stitch length adjustment pin (6) to move.
The sewing machine according to claim 2, characterized in that, the driving surface (3-11) is a gradually increasing distance from the cam rotation center (3-2) along one direction in the circumferential direction.形面。 Shape surface.
The sewing machine according to claim 2, characterized in that, the needle length adjusting surface (3-1) further comprises a holding surface (3-12) butted on one side of the driving surface (3-11) in the circumferential direction, The holding surface (3-12) is an equal-diameter arc surface with respect to the cam rotation center (3-2); in the presser foot lifting mode, the holding surface (3-12) is opposite to the The stitch length adjusting pin (6) slides and the swing plate seat remains stationary.
The sewing machine according to claim 2, characterized in that, the swing plate seat is connected with an elastic reset member, and the elastic reset member keeps the needle pitch adjusting pin (6) pressed against the needle pitch adjusting surface ( 3-1) Status on the top.
The sewing machine according to any one of claims 1 to 5, wherein the presser foot adjusting portion includes a presser foot hole (3-3) penetrating through the cam crank in the axial direction, and the presser foot The presser foot lifting pin (38) on the foot link can be movably inserted into the presser foot lifting hole (3-3); in the presser foot lifting mode, the presser foot lifting hole (3-3) ) The hole wall abuts the presser foot pin (38) and drives the presser foot pin (38); in the stitch length adjustment mode, the presser foot hole (3-3) is relative to the The presser foot lifting pin (38) moves and the presser foot lifting pin (38) remains stationary.
The sewing machine according to claim 6, wherein the presser foot lifting hole (3-3) is an arc-shaped hole, and the presser foot lifting hole (3-3) is relative to the cam rotation center ( 3-2) is equal-diameter arc.
The sewing machine according to claim 1, wherein the presser foot adjusting part includes a presser foot driving surface (65-1) provided on the outer peripheral surface of the cam crank, and the presser foot connecting rod rotates Connected to the presser foot lifting drive plate (74), the presser foot lifting drive plate (74) is rotatably connected to the casing, and the presser foot lifting drive plate (74) is provided with a presser foot lifting drive pin;

In the presser foot lifting mode, the cam crank rotates and drives the presser foot lifting driving plate (74) to rotate through the contact between the presser foot driving pin and the presser foot driving surface (65-1).
The sewing machine according to claim 8, characterized in that the plate seat adjusting part comprises a raised pin (65-2) fixed on the cam crank, and the swing plate seat passes through a stitch length connecting rod (68). Hingedly connected to the stitch length adjusting crank (64), the stitch length adjusting crank (64) is rotatably connected to the casing, the stitch length adjusting crank (64) is provided with a sliding groove (64-1), the convex The lifting pin (65-2) is movably inserted into the chute (64-1);

In the stitch length adjustment mode, the cam crank rotates and drives the stitch length adjustment crank (64) to rotate through the sliding groove (64-1), and the presser foot drive pin and the presser foot The foot drive surface (65-1) is separated;

In the presser foot raising mode, the protruding pin (65-2) moves in the sliding groove (64-1) and the stitch length adjusting crank (64) remains stationary.
The sewing machine according to claim 9, characterized in that a support (70) is fixed on the casing, a limit shock absorbing block (70-2) is provided on the support (70), and the swing plate An elastic reset member is connected between the seat and the support (70); in the presser foot lifting mode, the elastic reset member pulls the needle distance seat against the limit shock-absorbing block (70-2 ).