CN212152660U - Short thread end thread cutting mechanism and sewing machine - Google Patents

Abstract

The utility model provides a stub thread trimming mechanism and sewing machine, stub thread trimming mechanism move sword and second including the first sword that moves and can the interlock in opposite directions and move the sword and raise the part, and first sword and second move the below that the sword all set up faller in sewing machine, raise the part and act on first sword and second of moving and move the sword, be used for shortening first sword and second and move the interlock position of sword and the distance between the faller upper surface. The part of raising in this application makes the first interlock position that moves sword and second and move the sword on upper and lower direction more be close to in the upper surface of faller, so can shorten the stub length of remaining on the sewing material after the trimming, realize the trimming effect of stub, avoid the manual work to carry out the secondary and prune the stub, improve from this and make up efficiency to can satisfy the needs that the high-end was made up.

Description

Short thread end thread cutting mechanism and sewing machine

Technical Field

The utility model relates to a short thread end thread trimming mechanism.

The utility model discloses still relate to a sewing machine who includes above-mentioned stub thread trimming mechanism.

Background

At present, a thread cutting mechanism is provided in a sewing machine for cutting an upper thread and a lower thread at the end of sewing, thereby achieving automatic thread cutting. The thread cutting mechanism generally has two types of thread cutting mechanisms, namely a rotary thread cutting mechanism and a horizontal thread cutting mechanism, and the rotary thread cutting mechanism has two types of thread cutting mechanisms, namely a double-moving-knife thread cutting mechanism and a single-moving-knife thread cutting mechanism, for example: the application publication number is CN106894175A, which discloses an automatic thread trimming mechanism of a sewing machine, and the automatic thread trimming mechanism is a single-action knife thread trimming mechanism. However, when the existing thread trimming mechanism is used for trimming threads, the meshing positions of two movable cutters in the double-movable cutter thread trimming mechanism or the meshing positions of the movable cutters and the fixed cutters in the single-movable cutter thread trimming mechanism are far away from a needle falling hole on a needle plate, so that the length of thread ends remained on a sewing material after thread trimming is long, the long thread ends still need to be trimmed twice manually after automatic thread trimming, the requirement of high-end sewing cannot be met, and the efficiency is reduced.

SUMMERY OF THE UTILITY MODEL

In view of the above shortcomings of the prior art, the to-be-solved technical problem of the present invention is to provide a short thread end thread cutting mechanism, which can realize the thread cutting effect of the short thread end.

In order to realize the above object, the utility model provides a short thread end thread trimming mechanism, move sword and the second including the first sword that moves and can the interlock in opposite directions and move the sword and raise the part, first sword and the second of moving moves the below that the sword all set up faller in sewing machine, it acts on first sword and the second of moving to raise the part and moves the sword, is used for shortening first sword and the second and moves the interlock position of sword and the distance between the faller upper surface.

Furthermore, the short thread end trimming mechanism also comprises a first knife rest and a second knife rest which are rotatably arranged in the bottom plate of the sewing machine, and a lower shaft sleeve fixed in the bottom plate of the sewing machine, wherein the lower shaft sleeve is used for supporting a lower shaft in the sewing machine, the first movable knife is fixed on the first knife rest, and the second movable knife is fixed on the second knife rest; the lower shaft sleeve comprises a first shaft section and a second shaft section which are eccentrically arranged, the second tool rest and the second tool rest are both rotatably arranged on the periphery of the first shaft section, and the first shaft section of the lower shaft sleeve forms the lifting part; when the first movable cutter and the second movable cutter are meshed, the central axis of the peripheral surface of the first shaft section is higher than that of the peripheral surface of the second shaft section.

Furthermore, the short thread end trimming mechanism also comprises a first knife rest and a second knife rest which are rotatably arranged in the bottom plate of the sewing machine, the first movable knife is fixed on the first knife rest, and the second movable knife is fixed on the second knife rest; the lifting part comprises a first gasket fixedly arranged between the first movable cutter and the first cutter frame and a second gasket fixedly arranged between the second movable cutter and the second cutter frame.

Further, the short thread end trimming mechanism further comprises a trimming transmission assembly, and the trimming transmission assembly is connected between the lower shaft of the sewing machine and the first knife rest and the second knife rest.

Further, the trimming transmission assembly comprises a crank shaft, a first trimming crank, a second trimming crank, a trimming connecting rod and a transmission pin fixed on the second tool rest, the crank shaft is parallel to the lower shaft and is driven to rotate by the lower shaft, one end of the first trimming crank is fixed on the crank shaft, the other end of the first trimming crank, one end of the second trimming crank and one end of the trimming connecting rod are fixed, the other end of the trimming connecting rod is hinged to the first tool rest, and the other end of the second trimming crank is rotatably installed on the crank shaft and provided with a sliding groove in sliding fit with the transmission pin.

Furthermore, an avoiding groove is formed in the lower surface of the needle plate and is recessed upwards in the direction away from the first movable knife and the second movable knife.

Furthermore, a needle falling hole which is communicated up and down is formed in the needle plate, and the meshing position of the first movable knife and the second movable knife is located right below the needle falling hole.

The utility model also provides a sewing machine, be equipped with as above in the sewing machine the stub bar cut line mechanism.

As above, the utility model relates to a short thread end thread trimming mechanism and sewing machine has following beneficial effect:

in this application, raise the part and make first move the interlock position that moves sword and second and move the sword in the up-and-down direction and be close to more in the upper surface of faller, so can shorten the stub bar length of remaining on the sewing material after the trimming, realize the trimming effect of stub bar, avoid the manual work to carry out the secondary and prune the stub bar, improve from this and make up efficiency to can satisfy the needs that the high-end was made up.

Drawings

Fig. 1 is a schematic structural diagram of a short thread end trimming mechanism in the present application.

Fig. 2 is a partial schematic view of fig. 1 at the needle fall opening of the needle board.

Fig. 3 is a schematic partial structure diagram of the residual thread end after thread trimming of the thread end trimming mechanism in the application.

Fig. 4 is a schematic structural diagram of a trimming transmission assembly according to the present application.

Fig. 5 is a schematic structural view of a lower bushing according to the present application.

Fig. 6 is a schematic view of the connection of the first movable blade and the first blade holder in the present application.

Fig. 7 is a schematic view of the connection of the second moving blade and the second blade holder in the present application.

Fig. 8 is a schematic view of the structure of a needle board in the present application.

FIG. 9 is a flow chart of the operation of the sewing machine of the present application in cutting a thread.

Description of the element reference numerals

1 first moving knife

2 second moving knife

3 needle plate

31 escape groove

32-pin hole

4 bottom plate

5 first knife rest

6 second tool rest

7 lower shaft sleeve

71 first shaft section

72 second shaft section

8 lower shaft

9 first gasket

10 second gasket

11 crankshaft

12 first thread trimming crank

13 second thread trimming crank

131 chute

14 shear line connecting rod

15 drive pin

16 machine needle

17 seam material

18 facial line

19 bottom line

Detailed Description

The following description is provided for illustrative purposes, and other advantages and features of the present invention will become apparent to those skilled in the art from the following detailed description.

It should be understood that the drawings of the present application are only used to match the contents disclosed in the specification, so as to be known and read by those skilled in the art, and not to limit the practical limitations of the present invention, so that the present application does not have any technical significance, and any modification of the structure, change of the ratio relationship, or adjustment of the size should still fall within the scope of the present application without affecting the function and the achievable purpose of the present application. Meanwhile, the terms such as "upper", "lower", "left", "right", "middle", and the like used in the present specification are for convenience of description, and are not intended to limit the scope of the present invention, and changes or adjustments of the relative relationship thereof may be considered as the scope of the present invention without substantial changes in the technical content.

The utility model provides a sewing machine, be equipped with the stub thread trimming mechanism as above in this sewing machine. For convenience of description, in the following examples, the directions are defined as follows: as shown in fig. 1, the axial direction of the lower shaft 8 in the sewing machine is defined as the left-right direction, the direction of the lower shaft 8 towards the head of the sewing machine is the left direction, and the direction of the lower shaft 8 towards the tail of the sewing machine is the right direction; defining the moving direction of the sewing material 17 as the front direction when the sewing machine is sewing; a direction orthogonal to both the left-right direction and the front-rear direction is defined as an up-down direction.

FIG. 1 is a left side view of a sewing machine of the present application; as shown in fig. 1, the sewing machine according to the present application includes a bottom plate 4, a needle plate 3 fixed on the bottom plate 4, a needle 16 capable of reciprocating up and down, and a short thread end thread cutting mechanism, wherein a needle dropping hole 32 penetrating up and down and allowing the needle 16 to pass through up and down is formed in the needle plate 3, as shown in fig. 8; the short thread end thread trimming mechanism comprises a first movable cutter 1 and a second movable cutter 2 which can move in opposite directions and can be meshed with each other, and a lifting part, wherein the first movable cutter 1 and the second movable cutter 2 are arranged below a needle plate 3 in the sewing machine, and the lifting part acts on the first movable cutter 1 and the second movable cutter 2 and is used for shortening the distance between the meshed position of the first movable cutter 1 and the second movable cutter 2 and the upper surface of the needle plate 3.

When the sewing machine sews, as shown in fig. 1 to fig. 3, the sewing material 17 is pressed against the needle plate 3 by the presser foot in the sewing machine and moves forward under the action of the feed dog in the sewing machine, the needle 16 moves up and down, the needle 16 carries the upper thread 18 to pierce the sewing material 17 and cooperates with the rotating shuttle for providing the lower thread 19 in the sewing machine, and the sewing is completed. When sewing is finished, the first movable knife 1 and the second movable knife 2 in the short thread end thread cutting mechanism move oppositely until the two are occluded, and the upper thread 18 and the bottom thread 19 are cut. Particularly, when trimming, raise the part and make first move the interlock position that moves sword 1 and second and move sword 2 and be close to more in the upper surface of faller 3, so can shorten the end of a thread length of remaining on seam material 17 after the trimming is ended, realize the trimming effect of stub end, avoid the manual work to carry out the secondary trimming end of a thread, improve from this and make up efficiency to can satisfy the needs that the high-end was made up.

Preferably, the meshing position of the first movable knife 1 and the second movable knife 2 is located under the needle falling hole 32, namely the meshing position of the first movable knife 1 and the second movable knife 2 is located on the central axis of the needle falling hole 32, and the first movable knife 1 and the second movable knife 2 are combined with the lifting part to minimize the distance between the meshing position of the first movable knife 1 and the second movable knife 2 and the upper surface of the needle plate 3, so that the length of the thread head after thread trimming is minimized, the thread head on the reverse side of the sewing material 17 after the thread trimming is realized for one time is shorter, and the thread trimming effect of improving the sewing quality and needing no manual thread trimming is achieved.

Further, as shown in fig. 1 and 4, the stub thread trimming mechanism further includes a first blade holder 5 and a second blade holder 6 both rotatably mounted in the sewing machine base plate 4, a lower bushing 7 fixed in the sewing machine base plate 4, and a trimming transmission assembly; the lower shaft sleeve 7 is used for supporting a lower shaft 8 in the sewing machine; the first movable knife 1 is fixed on the first knife rest 5, and the second movable knife 2 is fixed on the second knife rest 6; the thread trimming transmission assembly is connected between a lower shaft 8 of the sewing machine and the first knife rest 5 and the second knife rest 6, and when trimming threads, the lower shaft 8 rotates, the first knife rest 5 and the second knife rest 6 are driven to rotate around the lower shaft sleeve 7 through the thread trimming transmission assembly, and then the first movable knife 1 and the second movable knife 2 are driven to rotate around the lower shaft sleeve 7; therefore, in the present application, the first movable blade 1 and the second movable blade 2 both move around the lower shaft sleeve 7.

Further, as shown in fig. 1 and 4, the thread cutting drive assembly includes a crank shaft 11, a first thread cutting crank 12, a second thread cutting crank 13, a thread cutting link 14, and a drive pin 15 fixed to the second blade carrier 6, the crank shaft 11 is rotatably installed in the base plate 4, the crank shaft 11 is parallel to the lower shaft 8 and is driven by the lower shaft 8 to rotate, the upper end of the first trimming crank 12 is fixed at the left end of the crank shaft 11, the lower end of the first trimming crank 12, the lower end of the second trimming crank 13 and the front end of the trimming connecting rod 14 are fixed through a fastening screw extending left and right, the rear end of the trimming connecting rod 14 is hinged with the first tool rest 5 through a shaft position screw extending left and right, the upper end of the second trimming crank 13 is rotatably installed at the left end of the middle crank shaft 11, the second trimming crank 13 is positioned at the left side of the first trimming crank 12, and a sliding groove 131 which is in sliding fit with the driving pin 15 is separately arranged at the rear section part of the upper end of the second trimming crank 13. The connecting structure between the lower shaft 8 and the crank shaft 11 is a conventional one, and reference is made to an automatic thread trimming mechanism of a sewing machine disclosed in chinese patent application publication No. CN106894175A, which will not be described herein. When in wire cutting, power is transmitted between the lower shaft 8 and the crank shaft 11, the lower shaft 8 drives the crank shaft 11 to rotate, the crank shaft 11 drives the first wire cutting crank 12 to rotate together, the first wire cutting crank 12 drives the first knife rest 5 to rotate around the lower shaft sleeve 7 through the wire cutting connecting rod 14, meanwhile, the first wire cutting crank 12 also drives the second knife rest 6 to rotate around the lower shaft sleeve 7 through the second wire cutting crank 13 and the transmission pin 15, the rotating directions of the first knife rest 5 and the second knife rest 6 are opposite, and therefore the opposite movement of the first movable knife 1 and the second movable knife 2 is realized.

Further, the raising means has the following two embodiments.

First embodiment of the raising member, as shown in fig. 5, the lower sleeve 7 includes a first shaft section 71 and a second shaft section 72 located on the right side of the first shaft section 71, the first shaft section 71 and the second shaft section 72 both extend in the left-right direction and are eccentrically located, a support hole in the lower sleeve 7, which is engaged with the lower shaft 8, penetrates the first shaft section 71 and the second shaft section 72 in the left-right direction, and the second shaft section 72 is rotatably installed in the sewing machine bed 4. The lifting part is a first shaft section 71 of the lower shaft sleeve 7; when the first movable knife 1 and the second movable knife 2 are engaged and cut lines, the central axis of the peripheral surface of the first shaft section 71 is higher than the central axis of the peripheral surface of the second shaft section 72 in the vertical direction, the second knife rest 6 and the second knife rest 6 are both rotatably installed on the periphery of the first shaft section 71, and the positions of the first knife rest 5 and the second knife rest 6 are raised through the first shaft section 71, namely the positions of the first movable knife 1 and the second movable knife 2 are raised, so that the distance between the engagement position of the first movable knife 1 and the second movable knife 2 and the needle plate 3 is shortened, the first movable knife 1 and the second movable knife 2 can be engaged and cut lines at the position nearest to the upper surface of the needle plate 3 during line cutting, and the shortest residual line head on the sewing material 17 is ensured. In this embodiment, when the lower shaft sleeve 7 is fixed to the bottom plate 3, the eccentric position is installed on the upper surface in the vertical direction, so that when the first moving blade 1 and the second moving blade 2 rotate the tangent line around the lower shaft sleeve 7, the first moving blade 1 and the second moving blade 2 just move to the eccentric highest point of the first shaft section 71 of the lower shaft sleeve 7, and the shortest distance from the upper surface of the needle plate 3 is achieved.

In the second embodiment of the raising component, as shown in fig. 6 and 7, the raising component includes a first spacer 9 fixedly arranged between the first movable blade 1 and the first blade holder 5, and a second spacer 10 fixedly arranged between the second movable blade 2 and the second blade holder 6, the first spacer 9 raises the position of the first movable blade 1, and the second spacer 10 raises the position of the second movable blade 2, so as to shorten the distance between the engagement position of the first movable blade 1 and the second movable blade 2 and the needle plate 3, and when thread trimming is performed, the first movable blade 1 and the second movable blade 2 can engage and trim the thread at the position closest to the upper surface of the needle plate 3, and the shortest residual thread end on the sewing material 17 is ensured. In the views shown in fig. 6 and 7, the first shim 9 is of a separate structure from the first holder 5, and the second shim 10 and the second holder 6 are also of a separate structure, while in other embodiments the first shim 9 may be of a unitary structure with the first holder 5, and the second shim 10 and the second holder 6 are also of a unitary structure, i.e.: the first spacer 9 may be an integrally extended raised portion of the first holder 5, and the second spacer 10 may be an integrally extended raised portion of the second holder 6.

Preferably, as shown in fig. 8, under the condition that the overall strength and thickness of the pin plate 3 are not changed, the avoidance groove 31 is partially formed in the lower surface of the pin plate 3 facing the first movable blade 1 and the second movable blade 2, and the avoidance groove 31 is recessed upwards in the direction away from the first movable blade 1 and the second movable blade 2, so as to avoid interference, for example, interference with screws for fixing the first movable blade 1, the first gasket 9 and the first knife rest 5, and interference with screws for fixing the second movable blade 2, the second gasket 10 and the second knife rest 6.

The sewing machine with the structure works in the following mode during thread cutting: as shown in fig. 9, a trimming command is input by pedaling or other means. After receiving the thread trimming command, the controller of the sewing machine controls the stitch length to be reduced to a small stitch length value of 0.3-1 mm or-0.3-1 mm from the current stitch length value, and after the sewing set stitch number, the controller sends a command to the thread trimming driving source, and the set stitch number is prestored in the controller. The thread cutting driving source acts to transmit power between the lower shaft 8 and the crank shaft 11 and control the feeding mechanism of the sewing machine to feed in the direction opposite to the original feeding direction, namely: if the sewing with small stitch length is a positive seam when the sewing stitch number is set, then a reverse seam is formed when the thread is cut; if the small stitch length sewing is reverse sewing when the sewing stitch number is set, then the thread is cut by positive sewing. The lower shaft 8 drives the crank shaft 11 to rotate, and the first movable knife 1 and the second movable knife 2 are driven to rotate around the lower shaft sleeve 7 oppositely through the first thread trimming crank 12, the thread trimming connecting rod 14, the first knife rest 5, the second thread trimming crank 13, the transmission pin 15 and the second knife rest 6, so that the upper thread 18 and the bottom thread 19 are trimmed. Through this working method, can cut off facial suture 18 and bottom thread 19 at facial suture 18 and bottom thread 19 in the twinkling of an eye facial suture 18 and bottom thread 19 and be in symmetrical state for tangent line position, realize that the end of a thread of facial suture 18 and bottom thread 19 is as short, guarantee neat pleasing to the eye of end of a thread after the trimming, need not artifical pruning, improve work efficiency, reduce the cost of labor, satisfy high-end requirement of making up.

To sum up, the utility model discloses various shortcomings in the prior art have effectively been overcome and high industry value has.

The above embodiments are merely illustrative of the principles and effects of the present invention, and are not to be construed as limiting the invention. Modifications and variations can be made to the above-described embodiments by those skilled in the art without departing from the spirit and scope of the present invention. Accordingly, it is intended that all equivalent modifications or changes which may be made by those skilled in the art without departing from the spirit and technical spirit of the present invention be covered by the claims of the present invention.

Claims (8)

1. The utility model provides a short thread end thread trimmer constructs, moves sword (2) including first moving sword (1) and the second that can move in opposite directions and can the interlock, first moving sword (1) and second move sword (2) and all set up the below of faller (3) in sewing machine, its characterized in that: the needle bar mechanism is characterized by further comprising a lifting part, wherein the lifting part acts on the first movable knife (1) and the second movable knife (2) and is used for shortening the distance between the meshing position of the first movable knife (1) and the second movable knife (2) and the upper surface of the needle plate (3).

2. The stub wire trimming mechanism of claim 1, wherein: the sewing machine further comprises a first knife rest (5) and a second knife rest (6) which are rotatably arranged in the bottom plate (4) of the sewing machine, and a lower shaft sleeve (7) fixed in the bottom plate (4) of the sewing machine, wherein the lower shaft sleeve (7) is used for supporting a lower shaft (8) in the sewing machine, the first movable knife (1) is fixed on the first knife rest (5), and the second movable knife (2) is fixed on the second knife rest (6); the lower shaft sleeve (7) comprises a first shaft section (71) and a second shaft section (72) which are eccentrically arranged, the second tool rest (6) and the second tool rest (6) are both rotatably arranged on the periphery of the first shaft section (71), and the first shaft section (71) of the lower shaft sleeve (7) forms the lifting part; when the first movable knife (1) and the second movable knife (2) are meshed, the central axis of the peripheral surface of the first shaft section (71) is higher than that of the peripheral surface of the second shaft section (72).

3. The stub wire trimming mechanism of claim 1, wherein: the sewing machine is characterized by further comprising a first knife rest (5) and a second knife rest (6) which are rotatably arranged in the bottom plate (4) of the sewing machine, wherein the first movable knife (1) is fixed on the first knife rest (5), and the second movable knife (2) is fixed on the second knife rest (6); the lifting component comprises a first gasket (9) fixedly arranged between the first movable cutter (1) and the first cutter rest (5) and a second gasket (10) fixedly arranged between the second movable cutter (2) and the second cutter rest (6).

4. The stub wire cutting mechanism according to claim 2 or 3, wherein: the thread cutting device further comprises a thread cutting transmission assembly, and the thread cutting transmission assembly is connected between a lower shaft (8) of the sewing machine and the first knife rest (5) and the second knife rest (6).

5. The stub wire trimming mechanism of claim 4, wherein: the trimming transmission assembly comprises a crank shaft (11), a first trimming crank (12), a second trimming crank (13), a trimming connecting rod (14) and a transmission pin (15) fixed on a second tool rest (6), wherein the crank shaft (11) is parallel to a lower shaft (8) and is driven to rotate by the lower shaft (8), one end of the first trimming crank (12) is fixed on the crank shaft (11), the other end of the first trimming crank (12), one end of the second trimming crank (13) and one end of the trimming connecting rod (14) are fixed, the other end of the trimming connecting rod (14) is hinged to the first tool rest (5), and the other end of the second trimming crank (13) is rotatably installed on the crank shaft (11) and is provided with a sliding groove (131) in sliding fit with the transmission pin (15).

6. The stub wire trimming mechanism of claim 1, wherein: offer on the lower surface of faller (3) and dodge groove (31), dodge groove (31) and upwards cave in to the direction of keeping away from first moving knife (1) and second moving knife (2).

7. The stub wire trimming mechanism of claim 1, wherein: a needle falling hole (32) which is communicated up and down is formed in the needle plate (3), and the meshing position of the first movable knife (1) and the second movable knife (2) is located right below the needle falling hole (32).

8. A sewing machine characterized by: the sewing machine is provided with the short thread cutting mechanism according to any one of claims 1 to 7.

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