CN217324551U

CN217324551U - Thread trimming mechanism

Info

Publication number: CN217324551U
Application number: CN202221348407.XU
Authority: CN
Inventors: 孙君
Original assignee: SUZHOU RIHE SEWING EQUIPMENT CO Ltd
Current assignee: SUZHOU RIHE SEWING EQUIPMENT CO Ltd
Priority date: 2022-05-31
Filing date: 2022-05-31
Publication date: 2022-08-30
Anticipated expiration: 2032-05-31

Abstract

The utility model provides a thread cutting mechanism for cutting off the suture thread penetrating through the needle hole on the needle plate, which comprises a movable cutter seat, a movable cutter and a fixed cutter, wherein the movable cutter seat is arranged below the needle plate, the fixed cutter is arranged on one side of the needle hole, the movable cutter top wall is provided with a cutting edge surface extending obliquely, the fixed cutter is arranged above the movable cutter, the fixed cutter comprises a cutter handle part far away from the needle hole and a cutting edge part close to the needle hole, the cutter handle part is detachably attached on the bottom wall of the needle plate, the cutting edge part extends obliquely from the bottom wall of the needle plate to the position under the needle hole, the thickness of the cutting edge part is gradually reduced in the extending direction, the end surface of the cutting edge part close to the needle hole is vertical to the horizontal plane, the lower edge of the end surface is the set of the lowest point of the cutting edge part, and the cutting edge parallel to the horizontal plane is formed, the suture thread can be vertically cut off by the contact of the cutting edge and the highest point surface of the cutting edge, the rigidity of the cutting edge part is improved, the elastic yielding is reduced, the thread trimming action is crisp, the thread fracture is smooth, the thread trimming effect is good, the debugging is convenient, the difficulty is small, and the thread trimming device is durable.

Description

Thread trimming mechanism

Technical Field

The utility model belongs to the technical field of the sewing machine, concretely relates to automatic sewing machine's thread trimming mechanism.

Background

Automatic sewing machine is by computer control, can accomplish the sewing machine of sewing process automatically, after the sewing, needs the trimming so that take off the sewing material, and the common trimming mechanism of automatic sewing machine sets up in faller one side mostly, and there is longer distance in the pinhole on trimming position and the faller, remains the thread end length on the sewing material behind the trimming, and the suture is extravagant big, influences the sewing material quality, and follow-up still needs the manual work to prune, and production efficiency is low, and intensity of labour is big.

In order to solve the problem, a thread trimming mechanism with short residual thread ends appears in the market, for example, chinese patent CN108457015A discloses a thread trimming mechanism of an automatic sewing machine of this kind, the fixed knife of the scheme is a 7-shaped sheet, and is vertically turned over, the lower end part of the fixed knife is fixed on the fixed knife seat, the upper end part of the fixed knife is provided with a fixed knife edge and is suspended outside the movable knife, the fixed knife edge cuts off the thread by contacting with the outer wall surface of the movable knife, and the arrangement makes the scheme have at least the following problems when in use:

1. the folding part of the fixed knife substantially forms a rotating shaft of the cutting edge of the fixed knife, the rotating shaft is perpendicular to the rotating plane of the movable knife, when the yarn is cut, the cutting edge of the fixed knife can rotate around the folding part to the direction far away from the outer wall surface of the movable knife under the pushing of the outer wall surface of the movable knife and the action of the elastic force of the fixed knife, so that elastic yielding is formed, the yarn cutting action is not crisp enough, the phenomenon of breakage and non-breakage is easy to occur, and the yarn cutting effect is poor.

2. When the movable and fixed cutters are matched and debugged, the fixed cutter angle and the fixed cutter position are adjusted, so that the difficulty is high; after the angle and/or position of the fixed cutter are/is changed, the elastic yielding degree of the fixed cutter is changed, the matching of the fixed cutter and the movable cutter is influenced, multiple adjustments are needed, and the operation is inconvenient.

3. The contact surface (or line) of the cutting edge of the fixed knife and the outer wall surface of the movable knife is parallel or approximately parallel to the axial direction of the suture, the abrasion to the cutting edge of the fixed knife is large during the thread shearing, and the service life is short.

SUMMERY OF THE UTILITY MODEL

The utility model aims at overcoming prior art's shortcoming, provide a trimming action crisp, trimming is effectual, the debugging is convenient and the degree of difficulty is little, durable's trimming mechanism, and the end of a thread that this trimming mechanism cut out is short, and the suture is extravagant little, does not influence the sewing material quality, need not artifical pruning, and production efficiency is high, intensity of labour is little, is particularly suitable for automatic sewing machine to use.

In order to achieve the above object, the present invention provides a thread cutting mechanism for cutting a thread passing through a needle hole in a needle plate, the thread cutting mechanism comprises a movable blade holder, a movable blade and a fixed blade, the movable blade holder is located below the needle plate, the fixed blade is located on one side of the needle hole, the top wall of the movable blade is provided with a cutting edge surface extending obliquely, the fixed blade is located above the movable blade, the fixed blade comprises a blade portion away from the needle hole and a cutting edge portion close to the needle hole, the blade portion is detachably attached to the bottom wall of the needle plate, the cutting edge portion extends obliquely from the bottom wall of the needle plate to the position under the needle hole, the thickness of the cutting edge portion is gradually reduced in the extending direction, the end surface of the cutting edge portion close to the needle hole is perpendicular to the horizontal plane, the lower edge of the end surface is the set of the lowest points of the cutting edge portion, and forms a cutting edge parallel to the horizontal plane, the cutting edge shears the suture line vertically by contact with the highest point of the cutting edge surface.

Preferably, the handle part is embedded in a positioning groove formed in the bottom wall of the needle plate, and a notch of the positioning groove is higher than the lower surface of the handle part.

Further preferably, the needle hole extends downwardly through a top wall of the positioning slot.

Further preferably, the groove depth of the positioning groove is less than or equal to 20% of the thickness of the needle plate.

Further preferably, the positioning groove is an arc-shaped groove, and the center of the arc-shaped groove is located on the extension line of the rotating axis of the rotating shuttle.

Preferably, the cutting edge is spaced from the pinhole by a distance of 3 ± 0.5 mm.

Preferably, the thickness of the thickest part of the cutting edge part is 2.4 to 2.8 times of the thickness of the handle part, and the thickness of the thinnest part of the cutting edge part is 1.1 to 1.3 times of the thickness of the handle part.

Preferably, the stationary knife further includes a connecting portion for connecting the shank portion and the cutting edge portion, and a thickness of the connecting portion gradually increases from the shank portion to the cutting edge portion.

Preferably, the thread trimming mechanism further comprises a limiting boss used for limiting the protruding position of the rotating shuttle, and the limiting boss is formed by the end part, close to the needle hole, of a transverse rib plate connected to the inner wall of the needle plate seat.

Preferably, the thread trimming mechanism further comprises a thread clamping plate which is 7-shaped, the upper end of the thread clamping plate is used for being matched with the upper surface of the limiting boss to clamp threads, and the lower end of the thread clamping plate is located on one side of the movable knife and connected to the longitudinal rib plate protruding outwards from the needle plate seat.

Because of the application of the technical scheme, compared with the prior art, the utility model has the following advantages:

1. the fixed knife is arranged above the movable knife, so that the cutting edge part of the fixed knife obliquely extends from the bottom wall of the needle plate to the position right below the needle hole, the distance between the cutting edge of the fixed knife and the needle hole in the horizontal direction can be shortened as far as possible, and the length of the thread end left on the sewing material is further reduced.

2. The thickness through making the blade portion reduces gradually in its extending direction, makes the blade portion be close to the terminal surface perpendicular to horizontal plane of pinhole, can enough strengthen the rigidity of blade portion, and the degree that reduces blade portion elasticity and give way greatly makes the trimming action dry and fragile fall, and the suture fracture levels, and the trimming is effectual, can form the space again between blade portion and faller, reduces the area of contact with the suture to reduce the wearing and tearing of suture and stationary knife.

3. The inclined edge surface is arranged on the top wall of the movable knife, so that the lower edge of the fixed knife edge part close to the end surface of the needle hole is the set of the lowest points of the edge part, and the cutting edge parallel to the horizontal plane is formed.

4. Because the fixed knife cutting edge and the movable knife edge opening face are in a vertical matching mode, the elastic yielding degree of the fixed knife is extremely small and can be almost ignored, when the fixed knife and the movable knife are matched and debugged, the height of the movable knife edge face in the vertical direction only needs to be adjusted, the debugging difficulty is small, and the debugging operation is convenient.

Drawings

Fig. 1, 2 and 3 are schematic perspective views of a preferred embodiment of the present invention.

Fig. 4, 5 and 6 are exploded views of the preferred embodiment of the present invention.

Fig. 7 is a front view of fig. 1.

Fig. 8 is an enlarged cross-sectional view in the direction of a-a in fig. 7.

Wherein: 10. a movable cutter seat; 20. moving a knife; 21. a cutting edge surface; 22. positioning the boss; 23. a hook line part; 24. an avoidance surface; 30. fixing a cutter; 31. a shank portion; 32. a blade portion; 321. an end face; 322. a cutting edge; 33. a connecting portion; 34. a screw; 40. a needle plate; 41. a pinhole; 42. positioning a groove; 50. a needle board seat; 51. a transverse rib plate; 52. a longitudinal rib; 60. a limiting boss; 70. a wire clamping plate; 71. a kidney-shaped hole; 72. and (4) screws.

Detailed Description

The following detailed description of the preferred embodiments of the present invention is provided to enable those skilled in the art to more easily understand the advantages and features of the present invention, and to make clear and definite definitions of the protection scope of the present invention.

The up-down, left-right, front-back directions described in the present invention refer to the up-down, left-right, front-back directions in fig. 1.

As shown in fig. 1 to 8, the thread cutting mechanism provided by the present invention is used for cutting a thread penetrating through a needle hole 41 of a needle plate 40, and comprises a movable knife holder 10, a movable knife 20 and a fixed knife 30 located at one side of the needle hole 41, wherein the end of the movable knife 20 far away from the needle hole 41 is supported at the top of the movable knife holder 10, the end of the movable knife 20 close to the needle hole 41 is provided with a cutting edge surface 21, a positioning boss 22 and a thread hooking portion 23, the cutting edge surface 21 is arranged at the top surface of the movable knife 20 and extends obliquely, the positioning boss 22 is arranged at the bottom wall of the movable knife 20 and protrudes downwards, the thread hooking portion 23 is connected to the outer wall of the movable knife 20 for hooking the thread passing through the needle hole 41, when the movable knife holder 10 rotates, the movable knife 20 can be driven to rotate, the rotation plane of the movable knife 20 is parallel to the horizontal plane, so that the cutting edge surface 21 and the fixed knife 30 cooperate to cut the thread; the fixed knife 30 is positioned above the movable knife 20, the fixed knife 30 comprises a handle part 31 far away from the needle hole 41 and a cutting edge part 32 close to the needle hole 41, the handle part 31 is detachably attached to the bottom wall of the needle plate 40, the cutting edge part 32 extends obliquely from the bottom wall of the needle plate 40 to the position right below the needle hole 41, the thickness of the cutting edge part 32 is gradually reduced in the extending direction, the thickness of the thickest part of the cutting edge part 32 is 2.4-2.8 times of the thickness of the handle part 31, the thickness of the thinnest part of the cutting edge part 32 is 1.1-1.3 times of the thickness of the handle part 31, the inclination degree of the upper surface of the cutting edge part 32 is larger than that of the lower surface of the cutting edge part 32, intuitively, the gradient of the upper surface of the cutting edge part 32 is steeper, the end surface 321 of the cutting edge part 32 close to the needle hole 41 is vertical to the horizontal plane, the lower edge of the end surface 321 is the collection of the lowest points of the cutting edge part 32, the lower edge forms a cutting edge 322 parallel to the horizontal plane, when the knife holder 20 rotates along with the movable knife 10, cutting edge 322 shears the suture vertically by contact with the highest point of the edge face 21.

The advantages of such an arrangement are:

1. the distance between the cutting edge of the fixed knife and the needle hole in the horizontal direction can be shortened as much as possible, so that the length of the thread end remained on the sewing material is further reduced.

2. The rigidity of the edge part can be enhanced, the elastic yielding degree of the edge part is greatly reduced, the thread cutting action is enabled to be dry and crisp, the thread fracture is smooth, the thread cutting effect is good, a gap can be formed between the edge part and the needle plate, the contact area with the thread is reduced, and therefore the abrasion of the thread and the fixed knife is reduced.

3. The cutting blade parallel to the horizontal plane can be formed, when the movable blade rotates, the suture line can be vertically cut through the contact between the cutting blade and the highest point of the cutting edge surface, the abrasion to the cutting blade of the fixed blade during thread cutting is small, the service life is long, and the fixed blade is durable.

4. Because the cutting edge of the fixed knife and the opening surface of the movable knife are in a vertical matching mode, and the handle part of the fixed knife is attached to the bottom wall of the needle plate, the degree of elastic yielding generated by the cutting edge part of the fixed knife in the vertical direction is extremely low and can be almost ignored.

Seted up constant head tank 42 on the faller 40 diapire, handle of a knife portion 31 inlays to be established in constant head tank 42, and fixed through screw 34, the groove depth of constant head tank 42 can not be too big, too big intensity that can reduce faller 40, also can not the undersize, the undersize can not play the positioning action, preferably, the groove depth of constant head tank 42 is 10% -20% of faller 40 thickness, in this embodiment, the thickness of faller 40 is 1.7mm, the thickness of constant head tank 42 is 0.3mm, the notch of constant head tank 42 is higher than the lower surface of handle of a knife portion 31, the benefit that sets up like this lies in, can make the thickness of handle of a knife portion 31 not receive the influence of constant head tank 42 groove depth, thereby ensure the intensity of stationary knife 30.

In this embodiment, the positioning groove 42 is an arc-shaped groove, the center of the arc-shaped groove is located on the extension line of the rotating axis of the rotating shuttle, the advantages of the arrangement are that when the cutting edge part 32 is impacted by the cutting edge surface 21, the impact force can be uniformly dispersed on the inner wall of the positioning groove 42 which is contacted with the cutter handle part 31, the abrasion of the positioning groove 42 is reduced, even if the screw 34 is loosened due to frequent impact, the cutter handle part 31 can be clamped by the inner wall of the positioning groove 42, and the position of the cutter handle part in the horizontal direction is not easy to change.

In this embodiment, the needle hole 41 vertically penetrates the top wall of the positioning slot 42 downwards, the needle hole 41 is a kidney-shaped hole extending along the left-right direction, and the cutting edge 322 horizontally extends along the front-back direction, so that the thread hooking portion 23 rotates along with the movable knife 20 to drive the suture to advance, and the cutting edge 322 can be enabled to be horizontally arranged on the advancing path of the suture, thereby further optimizing the cutting effect of the suture.

In this embodiment, the distance from the cutting edge 322 to the needle hole 41 is 3 ± 0.5mm, which is much smaller than the distance from the needle hole 41 to the end face of the needle plate 40 (in the prior art, the distance is usually greater than 10 mm), and the technical effect of controlling the length of the residual thread end to be about 3mm can be achieved.

In the present embodiment, the stationary blade 30 further includes the connecting portion 33 for connecting the shank portion 31 and the cutting edge portion 32, and the thickness of the connecting portion 33 gradually increases from the shank portion 31 to the cutting edge portion 32, which is advantageous in that the stationary blade 30 can be made smoother as a whole.

In this embodiment, the needle plate 40 is fixed on the top of the needle plate seat 50, a transverse rib 51 and a longitudinal rib 52 are provided in the needle plate seat 50 to increase the strength thereof, the transverse rib 51 is inserted between the movable knife 20 and the rotary hook, the end portion thereof near the needle hole 41 forms a limit boss 60 for limiting the protruding position of the rotary hook, and the longitudinal rib 52 extends outward and protrudes out of the end face of the needle plate seat 50.

The thread trimming mechanism further comprises a thread clamping plate 70, the thread clamping plate 70 is 7-shaped, the upper end portion of the thread clamping plate is used for being matched with the upper surface of the limiting boss 60 to clamp threads, the lower end portion of the thread clamping plate is located on one side of the movable knife 20 and can be connected to the end face of the longitudinal rib plate 52 protruding outwards of the needle plate seat 50 in a vertically moving mode, specifically, a waist-shaped hole 71 extending in the vertical direction is formed in the lower end portion of the thread clamping plate 70, a screw 72 used for fixing the thread clamping plate 70 on the longitudinal rib plate penetrates through the waist-shaped hole 71, and the thread clamping plate 70 can be conveniently fixed and adjusted in height through the lateral fixing space vacated by the position change of the fixed knife 30.

In order to further prolong the service life of the cutting edge part 32 of the fixed knife 30, in the embodiment, the upper surface of the movable knife 20 is further provided with the relief surface 24 lower than the lowest point of the cutting edge surface 21, and the relief surfaces 24 are arranged on two sides of the cutting edge surface 21.

The utility model provides a thread trimming mechanism only needs to change faller, faller seat, stationary knife and clamp and can realize the transformation to current thread trimming mechanism, and is little to the change of current mechanism, and the part easy dismounting of changing, easy operation, the transformation is with low costs.

The above embodiments are only for illustrating the technical concept and features of the present invention, and the purpose of the embodiments is to enable people skilled in the art to understand the contents of the present invention and to implement the present invention, which cannot limit the protection scope of the present invention. All equivalent changes and modifications made according to the spirit of the present invention should be covered in the protection scope of the present invention.

Claims

1. The utility model provides a thread trimming mechanism for cut and wear to establish the downthehole suture of faller upper needle, thread trimming mechanism is including being located the movable cutter seat of faller below, move the sword, and be located the stationary knife of pinhole one side, the roof that moves the sword is equipped with the cutting edge face that the slope extends, its characterized in that:

the stationary knife is located move the sword top, the stationary knife is including keeping away from the handle of a knife portion of pinhole with be close to the blade portion of pinhole, handle of a knife portion detachably laminates on the diapire of faller, the blade portion certainly the diapire of faller to extend to the slope under the pinhole, the thickness of blade portion reduces gradually on its extending direction, the blade portion is close to the terminal surface perpendicular to horizontal plane of pinhole, the lower edge of this terminal surface do the set of blade portion minimum to form the cutting edge that is on a parallel with the horizontal plane, the cutting edge through with the contact of blade surface peak is cut perpendicularly the suture.

2. The thread trimming mechanism of claim 1, wherein: the handle part is embedded in a positioning groove formed in the bottom wall of the needle plate, and the notch of the positioning groove is higher than the lower surface of the handle part.

3. The thread trimming mechanism of claim 2, wherein: the needle hole penetrates through the top wall of the positioning groove downwards.

4. The thread trimming mechanism of claim 2, wherein: the depth of the positioning groove is less than or equal to 20% of the thickness of the needle plate.

5. The thread trimming mechanism of claim 2, wherein: the positioning groove is an arc-shaped groove, and the circle center of the arc-shaped groove is positioned on the extension line of the rotating axis of the rotating shuttle.

6. The thread trimming mechanism of claim 1, wherein: the distance between the cutting edge and the needle hole is 3 +/-0.5 mm.

7. The thread trimming mechanism according to claim 1, wherein: the thickness of the thickest part of the cutting edge part is 2.4 to 2.8 times of the thickness of the cutter handle part, and the thickness of the thinnest part of the cutting edge part is 1.1 to 1.3 times of the thickness of the cutter handle part.

8. The thread trimming mechanism of claim 1, wherein: the fixed knife further comprises a connecting part used for connecting the knife handle part and the cutting edge part, and the thickness of the connecting part is gradually increased from the knife handle part to the cutting edge part.

9. The thread trimming mechanism of claim 1, wherein: the thread trimming mechanism further comprises a limiting boss used for limiting the protruding position of the rotating shuttle, and the limiting boss is formed by the end portion, close to the needle hole, of a transverse rib plate connected to the inner wall of the needle plate seat.

10. The thread trimming mechanism of claim 9, wherein: the thread trimming mechanism further comprises a thread clamping plate which is 7-shaped, the upper end of the thread clamping plate is used for being matched with the upper surface of the limiting boss to clamp threads, and the lower end of the thread clamping plate is located on one side of the movable knife and connected to the longitudinal rib plate protruding outwards of the needle plate seat.