Thread loosening mechanism of sewing machine and sewing machine thereof

Abstract

The thread loosening mechanism comprises a presser foot lifting front lever component, a thread loosening plate is hinged to one side of the lower end of the presser foot lifting front lever component, an upper push plate portion is arranged at the upper end of the thread loosening plate, a push head portion is arranged on one side of the presser foot lifting front lever component, and the push head portion abuts against the upper push plate portion. The presser foot lifting front lever sub-component pushes the thread loosening plate to swing through the push head part; a lower push plate part is obliquely arranged at the lower end of the thread loosening plate, a thread loosening shaft penetrating through the thread clamping device is arranged in front of the lower push plate part, the lower push plate part is in contact with the thread loosening shaft, and the lower push plate part pushes the thread loosening shaft to axially move along with swinging of the thread loosening plate so as to drive two thread clamping pieces of the thread clamping device to be separated or closed. According to the thread loosening mechanism, the lifting plate and the thread loosening plate are of a separated structure, the two thread clamping pieces of the thread clamping device are driven to be separated or closed through the thread loosening plate, the thread loosening plate can be detached independently, maintenance personnel can detach the thread loosening plate without manual thread loosening operation, and maintenance of the maintenance personnel is facilitated.

Description

Technical Field

[0001] The utility model relates to sewing equipment, in particular to a thread loosening mechanism of a sewing machine and the sewing machine. Background Art

[0002] The thread loosening mechanism is an important and common mechanism in sewing machines. The working principle of the existing thread loosening mechanism is that the presser foot lifting mechanism or the manual wrench mechanism drives the presser foot lifting front lever sub-assembly to swing, and the lower end of the presser foot lifting front lever sub-assembly is hinged with a lifting plate, and the presser foot lifting front lever sub-assembly swings and drives the lifting plate to rise and fall, and the lifting plate is integrally formed with an inclined surface for driving the two thread clamping pieces of the thread clamp to separate or close. For example, a thread loosening device disclosed in announcement number CN210529215U, although this structure is relatively simple and has fewer components, it also has some defects, namely, the inclined surface structure driving the thread clamp is integrally formed on the lifting plate, which makes it impossible to disassemble the thread loosening mechanism separately when maintaining it, and workers need to manually loosen the thread before disassembling it. Utility Model Content

[0003] The utility model aims at the shortcomings of the prior art and provides a thread loosening mechanism of a sewing machine and the sewing machine.

[0004] In order to solve the above technical problems, the utility model is solved by the following technical solutions:

[0005] The thread loosening mechanism of the sewing machine comprises a presser foot front lever subassembly, a thread loosening plate is hingedly connected to one side of the lower end of the presser foot front lever subassembly, an upper push plate portion is provided at the upper end of the thread loosening plate, a push head portion is provided at one side of the presser foot front lever subassembly, the push head portion abuts against the upper push plate portion, and the presser foot front lever subassembly pushes the thread loosening plate to swing through the push head portion;

[0006] A tilted push plate portion is provided at the lower end of the wire loosening plate, and a wire loosening shaft that passes through the wire clamp is provided in front of the push plate portion. The push plate portion contacts the wire loosening shaft, and the push plate portion pushes the wire loosening shaft to move axially as the wire loosening plate swings, thereby driving the two wire clamping pieces of the wire clamp to separate or close.

[0007] Preferably, the upper end of the loose wire plate is bent forward obliquely to form an upper bending portion, and the side edge of the upper bending portion is bent backward to form an upper push plate portion.

[0008] Preferably, the surface of the lower push plate portion connected to the wire loosening shaft is an inclined push surface, the front end surface of the wire loosening plate is a reference surface, and the inclined push surface extends to intersect with the reference surface.

[0009] Preferably, the lower end side of the loose wire plate is bent forward to form a lower bending portion, the end of the lower bending portion is bent outward to form a connecting portion, and the end of the connecting portion is provided with a lower push plate portion.

[0010] Preferably, a lower connecting shaft is installed at the lower end of the wire loosening plate, a torsion spring is installed on the lower connecting shaft and abuts against the casing, and the other end of the torsion spring abuts against the lower bending portion.

[0011] Preferably, the inner end of the loose wire shaft is provided with an abutment boss surrounding it, and the push-down plate abuts against the abutment boss.

[0012] Preferably, a guide limit hole is provided on the wire loosening plate, the end of the upper connecting shaft on the presser foot lifting front lever sub-component passes through the guide limit hole and is installed with a clamping ring, the wire loosening plate is limited between the clamping ring and the presser foot lifting front lever sub-component, and the wire loosening plate swings around the upper connecting shaft.

[0013] Preferably, the guide limiting hole is an arc-shaped extending guide limiting hole.

[0014] Preferably, a lifting plate is hinged at the lower end of the presser foot lifting front lever sub-component, a side plate of the lifting plate is provided with a notch, and the lower end of the thread loosening plate is fitted in the notch.

[0015] A sewing machine, including a thread releasing mechanism of the sewing machine.

[0016] The utility model has significant technical effects due to the adoption of the above technical solutions:

[0017] In the wire loosening mechanism, the lifting plate and the wire loosening plate are separate structures. The wire loosening plate is used to drive the two wire clamping pieces of the wire clamp to separate or close. The wire loosening plate can be disassembled separately, and maintenance personnel do not need to manually perform wire loosening operations to remove it, which is convenient for maintenance personnel to maintain. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a structural schematic diagram of the utility model.

[0019] Figure 2 It is a structural diagram of the loose wire board.

[0020] Figure 3 It is a structural diagram of the lifting plate.

[0021] The parts indicated by the numbers in the above drawings are as follows:

[0022] 1—Lifting the front lever of the presser foot, 11—Pushing the head

[0023] 2-wire loosening plate, 21-upper push plate portion, 22-lower push plate portion, 23-upper bending portion, 24-lower bending portion, 25-connecting portion, 26-, 200-reference surface, 221-inclined push surface

[0024] 3—Wire clamp

[0025] 4-loosening shaft, 41-butting boss

[0026] 5—Lower connecting shaft

[0027] 6—Torsion spring

[0028] 7—Upper connecting shaft

[0029] 8—Snap ring

[0030] 9—lifting plate, 91—notch

[0031] 10—Manual wire release wrench DETAILED DESCRIPTION

[0032] The following is combined with Figure 1-3 The utility model is further described in detail with examples.

[0033] Example 1

[0034] The thread loosening mechanism of the sewing machine comprises a presser foot lifting front lever subassembly 1, a thread loosening plate 2 is hingedly connected to one side of the lower end of the presser foot lifting front lever subassembly 1, an upper push plate portion 21 is provided at the upper end of the thread loosening plate 2, a push head portion 11 is provided at one side of the presser foot lifting front lever subassembly 1, the push head portion 11 is a convex portion, the push head portion 11 abuts against the upper push plate portion 21, and the presser foot lifting front lever subassembly 1 pushes the thread loosening plate 2 to swing through the push head portion 11. The presser foot lifting mechanism drives the presser foot lifting front lever subassembly 1 to swing, and the push head portion 11 of the presser foot lifting front lever subassembly 1 abuts against the upper push plate portion 21, thereby driving the thread loosening plate 2 to swing. The lower end of the loosening plate 2 is provided with an inclined lower push plate portion 22, and a loosening shaft 4 is provided in front of the lower push plate portion 22 and penetrates the wire clamp 3. The lower push plate portion 22 contacts the loosening shaft 4, and the lower push plate portion 22 pushes the loosening shaft 4 to move axially as the loosening plate 2 swings, driving the two clamping pieces of the wire clamp 3 to separate or close. The split loosening plate 2 can be disassembled separately, and maintenance personnel can remove it without manually loosening the wire.

[0035] The thread loosening mechanism also includes a manual thread loosening wrench 10, which is in contact and connected with the front lever subassembly 1 of the presser foot lifter. When the operator operates the manual thread loosening wrench 10, the front lever subassembly 1 of the presser foot lifter can be driven to swing, and the front lever subassembly of the presser foot lifter can synchronously drive the thread loosening plate 2 to swing, thereby realizing the thread loosening function.

[0036] The upper end of the wire loosening plate 2 is bent forward at an angle to form an upper bending portion 23, and the side of the upper bending portion 23 is bent backward to form an upper push plate portion 21. The upper push plate portion 21 is enabled to face the push head portion 11 of the presser foot front lever sub-component 1 through the upper bending portion 23. At the same time, the upper push plate portion 21 is a part of the wire loosening plate 2, and the upper push plate portion 21 has a high connection strength.

[0037] The surface of the lower push plate 22 connected to the loosening shaft 4 is an inclined push surface 221, and the front end surface of the loosening plate 2 is a reference surface 200, and the inclined push surface 221 extends to intersect with the reference surface 200. The inclined push surface 221 can drive the loosening shaft 4 to move forward and backward when driven, thereby realizing the loosening function.

[0038] The side edge of the lower end of the wire loosening plate 2 is bent forward to form a lower bending portion 24, and the lower bending portion 24 is perpendicular to the wire loosening plate 2. The end of the lower bending portion 24 is bent outward to form a connecting portion 25. The connecting portion 25 is arranged horizontally and perpendicular to the lower bending portion 24. A lower push plate portion 22 is provided at the end of the connecting portion 25. The lower push plate portion 22 is integrated with the connecting portion 25. The lower push plate portion 22 is integrally formed on the wire loosening plate 2, and the lower push plate portion 22 has a high connection strength.

[0039] The lower end of the thread loosening plate 2 is provided with a lower connecting shaft 5, and a torsion spring 6 is provided on the lower connecting shaft 5, which is against the housing, and the other end of the torsion spring 6 is against the lower bending portion 24. The torsion spring 6 plays a reset role, which enables the thread loosening plate 2 to be firmly pressed against the front lever subassembly 1 of the presser foot lifting device, and when the front lever subassembly 1 of the presser foot lifting device swings, the thread loosening plate 2 can respond immediately.

[0040] The inner end of the loosening shaft 4 is provided with an abutting boss 41 surrounding it, and the lower push plate portion 22 abuts on the abutting boss 41. The abutting boss 41 extends the contact surface, making it easier for the lower push plate portion 2 to contact it, thereby facilitating pushing the loosening shaft 4.

[0041] The thread loosening plate 2 is provided with a guide limit hole 26, which is an arc-shaped guide limit hole. The end of the upper connecting shaft 7 on the presser foot lifting front lever subassembly 1 passes through the guide limit hole 26 and is installed with a clamp ring 8. The thread loosening plate 2 is limited between the clamp ring 8 and the presser foot lifting front lever subassembly 1, and the thread loosening plate 2 swings around the upper connecting shaft 7. The guide limit hole 26 plays a guiding role on the one hand, and is used to limit the swing amplitude of the thread loosening plate 2 on the other hand.

[0042] Example 2

[0043] The features of Example 2 are basically the same as those of Example 1, except that a lifting plate 9 is hingedly connected to the lower end of the presser foot lifting front lever subassembly 1, and a side plate of the lifting plate 9 is provided with a notch 91. The lower end of the loosening plate 2 fits in the notch 91, and the notch 91 prevents the loosening plate 2 from interfering with the lifting plate 9, and the structures of the two are more compact.

[0044] Example 3

[0045] A sewing machine, comprising the thread loosening mechanism of the sewing machine in embodiment 1 or 2.

Claims

1. A thread loosening mechanism for a sewing machine, comprising a presser foot lifting front lever subassembly (1), characterized in that: A thread loosening plate (2) is hingedly connected to one side of the lower end of the presser foot lifting front lever subassembly (1), an upper push plate portion (21) is provided at the upper end of the thread loosening plate (2), a push head portion (11) is provided on one side of the presser foot lifting front lever subassembly (1), the push head portion (11) abuts against the upper push plate portion (21), and the presser foot lifting front lever subassembly (1) pushes the thread loosening plate (2) to swing through the push head portion (11); The lower end of the wire loosening plate (2) is provided with an inclined lower push plate portion (22), and a wire loosening shaft (4) passing through the wire clamp (3) is provided in front of the lower push plate portion (22). The lower push plate portion (22) contacts the wire loosening shaft (4), and the lower push plate portion (22) pushes the wire loosening shaft (4) to move axially as the wire loosening plate (2) swings, thereby driving the two wire clamping pieces of the wire clamp (3) to separate or close.

2. The thread loosening mechanism of a sewing machine according to claim 1, characterized in that: The upper end of the loosening plate (2) is bent forwardly and tilted to form an upper bending portion (23), and the side of the upper bending portion (23) is bent backward to form an upper pushing plate portion (21).

3. The thread loosening mechanism of a sewing machine according to claim 1, characterized in that: The surface on the lower push plate portion (22) connected to the wire loosening shaft (4) is an inclined push surface (221), the front end surface of the wire loosening plate (2) is a reference surface (200), and the inclined push surface (221) extends to intersect with the reference surface (200).

4. The thread loosening mechanism of a sewing machine according to claim 3, characterized in that: The lower end side of the loose wire plate (2) is bent forward to form a lower bending portion (24), the end of the lower bending portion (24) is bent outward to form a connecting portion (25), and the end of the connecting portion (25) is provided with a lower push plate portion (22).

5. The thread loosening mechanism of a sewing machine according to claim 4, characterized in that: A lower connecting shaft (5) is installed at the lower end of the loosening plate (2), a torsion spring (6) abutting against the casing is installed on the lower connecting shaft (5), and the other end of the torsion spring (6) abuts against the lower bending part (24).

6. The thread loosening mechanism of a sewing machine according to claim 1, characterized in that: The inner end of the loosening shaft (4) is provided with an abutting boss (41) surrounding the inner end, and the lower push plate (22) abuts against the abutting boss (41).

7. The thread loosening mechanism of a sewing machine according to claim 1, characterized in that: A guide limit hole (26) is provided on the thread loosening plate (2); an end of an upper connecting shaft (7) on the presser foot lifting front lever sub-component (1) passes through the guide limit hole (26) and is provided with a clamping ring (8); the thread loosening plate (2) is limited between the clamping ring (8) and the presser foot lifting front lever sub-component (1); and the thread loosening plate (2) swings around the upper connecting shaft (7).

8. The thread loosening mechanism of a sewing machine according to claim 7, characterized in that: The guide limiting hole (26) is an arc-shaped extending guide limiting hole.

9. The thread loosening mechanism of a sewing machine according to any one of claims 1 to 8, characterized in that: A lifting plate (9) is hingedly connected to the lower end of the presser foot lifting front lever sub-component (1), a side plate of the lifting plate (9) is provided with a notch (91), and the lower end of the thread loosening plate (2) is matched at the notch (91).

10. A sewing machine, characterized in that: A thread loosening mechanism for a sewing machine comprising the thread loosening mechanism as described in any one of claims 1 to 9.

Images