Thread loosening mechanism and sewing machine thereof

Abstract

The utility model relates to sewing machine equipment, and discloses a thread loosening mechanism and a sewing machine thereof, the thread loosening mechanism comprises a presser foot lifting front lever sub-component, a thread loosening shaft and a thread trapper, the lower end of the presser foot lifting front lever sub-component is hinged with a lifting plate, and the thread loosening shaft is connected with the thread trapper and drives two thread clamping pieces of the thread trapper to be separated or closed; and a deflector rod is fixed on the lifting plate, one end of the wire loosening plate is a first poking part, the other end of the wire loosening plate is a second poking part, the deflector rod abuts against the first poking part and drives the first poking part to swing, and when the wire loosening plate swings, the first poking part is connected with the wire loosening shaft and drives the wire loosening shaft to move axially. 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 machine equipment, in particular to a thread loosening mechanism and a sewing machine thereof. Background Art

[0002] The thread loosening mechanism is a common mechanism in sewing machines. The working principle of the thread loosening mechanism is that the presser foot lifting mechanism or the manual toggle assembly drives the presser foot lifting front lever sub-assembly to swing, and the presser foot lifting front lever sub-assembly drives the lifting plate to rise and fall. Since the two thread clamping pieces of the driving thread clamp are separated or closed, the structure is integrally formed on the lifting plate. This results in the inability to disassemble the thread loosening mechanism separately when maintaining it, and the entire lifting plate can only be disassembled for maintenance. For example, a thread loosening device disclosed in announcement number CN210529215U has a relatively simple structure and few parts, but due to the above-mentioned defects, workers need to manually loosen the thread before disassembling it, and the thread loosening mechanism is relatively cumbersome to maintain. Utility Model Content

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

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

[0005] A thread loosening mechanism comprises a presser foot front lever subassembly, a thread loosening shaft and a thread clamp, wherein a lifting plate is hingedly connected at the lower end of the presser foot front lever subassembly, the thread loosening shaft is connected to the thread clamp and drives two thread clamping pieces of the thread clamp to separate or close; a thread loosening plate is hingedly connected to a casing, a lever is fixed on the lifting plate, one end of the thread loosening plate is a first toggle part, and the other end is a second toggle part, the lever abuts against the first toggle part and drives it to swing, and when the thread loosening plate swings, the first toggle part is connected to the thread loosening shaft and drives it to move axially.

[0006] Preferably, the first toggle part comprises an upper toggle rod and a lower toggle rod, a channel is provided between the upper toggle rod and the lower toggle rod, and the toggle rod passes through the channel and is connected to the first toggle part.

[0007] Preferably, the second driving portion includes a first bending portion and a second bending portion, the first bending portion is bent forward on the body of the wire loosening plate, the second bending portion is bent upward on the first bending portion, and the second bending portion is connected to the wire loosening shaft and drives the wire clamp to operate.

[0008] Preferably, the first bending portion includes a connecting portion and an extending portion, the connecting portion is perpendicular to the extending portion, and the second bending portion is provided at an end of the extending portion.

[0009] Preferably, the end surface of the second bending portion facing the wire loosening axis is a guide surface, the guide surface is an inclined surface, and the width of the lower end of the second bending portion is smaller than the width of the upper end thereof.

[0010] Preferably, the guide surface is an arc-shaped inclined surface.

[0011] Preferably, the lifting plate is integrated, comprising a first connecting rod portion and a second connecting rod portion, the first connecting rod portion and the second connecting rod portion intersecting and not on the same straight line, the upper end of the first connecting rod portion being hinged to the presser foot lifting front lever sub-component, and the shifting rod being arranged at the intersection of the first connecting rod portion and the second connecting rod portion.

[0012] Preferably, the inner end of the loosening shaft is provided with a boss surrounding it, and the second shifting part abuts against the boss.

[0013] Preferably, a manual toggle assembly for driving the presser foot front lever sub-assembly to rotate is installed on the side of the presser foot front lever sub-assembly.

[0014] A sewing machine comprises a thread loosening mechanism.

[0015] The utility model has significant technical effects due to the adoption of the above technical solutions:

[0016] 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

[0017] Figure 1 It is a structural schematic diagram of the utility model.

[0018] Figure 2 It is a structural diagram of the loose wire board.

[0019] Figure 3 It is a schematic diagram of the structure after the lifting plate and the lever are combined.

[0020] The parts indicated by the numbers in the above drawings are as follows:

[0021] 1—Lifting the front lever of the presser foot

[0022] 2—Loose spool

[0023] 3—Wire clamp

[0024] 4 - lifting plate, 41 - first connecting rod, 42 - second connecting rod

[0025] 5—Lever

[0026] 6—loosening plate, 61—first toggle part, 62—second toggle part, 611—upper toggle rod, 612—lower toggle rod, 613—channel, 621—first bending part, 622—second bending part, 6211—connecting part, 6212—extending part, 6221—guide surface

[0027] 7—Boss

[0028] 8—Manual toggle assembly DETAILED DESCRIPTION

[0029] The following is combined with Figure 1-3 The utility model is further described in detail with examples.

[0030] Example 1

[0031] A thread loosening mechanism comprises a presser foot front lever subassembly 1, a thread loosening shaft 2 and a thread clamp 3. The lower end of the presser foot front lever subassembly 1 is hinged with a lifting plate 4. The swing of the presser foot front lever subassembly 1 can drive the lifting plate 4 to rise and fall, thereby realizing presser foot lifting. The thread loosening shaft 2 is connected to the thread clamp 3 and drives two thread clamping pieces of the thread clamp 3 to separate or close. A thread loosening plate 6 is hinged on the casing, and a lever 5 is fixed on the lifting plate 4. One end of the thread loosening plate 6 is a first toggle part 61, and the other end is a second toggle part 62. The lever 5 abuts against the first toggle part 61 and drives it to swing. When the thread loosening plate 6 swings, the first toggle part 61 is connected to the thread loosening shaft 2 and drives it to move axially, thereby driving the two thread clamping pieces of the thread clamp 3 to separate or close, thereby realizing the thread loosening function. The wire loosening plate 6 and the lifting plate 4 of the wire loosening mechanism are not integrated, but are of split design. Although the wire loosening plate 6 is driven by the lifting plate 4, when maintaining the wire loosening mechanism, the maintenance personnel can maintain the wire loosening mechanism without disassembling the lifting plate 4, thereby improving the maintenance efficiency.

[0032] The first toggle part 61 includes an upper toggle rod 611 and a lower toggle rod 612. A channel 613 is provided between the upper toggle rod 611 and the lower toggle rod 612. The channel 613 is a U-shaped groove structure. The toggle rod 5 passes through the channel 613 and is connected to the first toggle part 61. When the lifting plate 4 descends, the toggle rod 5 abuts against the lower toggle rod 612 and drives the drive to swing counterclockwise, and the two clamping pieces of the clamp 3 are separated; when the lifting plate 4 rises, the toggle rod 5 abuts against the upper toggle rod 611 and drives the drive to swing clockwise, and the two clamping pieces of the clamp 3 are closed.

[0033] The second driving portion 62 includes a first bending portion 621 and a second bending portion 622. The first bending portion 621 is bent forward on the body of the wire loosening plate 6, and the second bending portion 622 is bent upward on the first bending portion 621. The second bending portion 622 is connected to the wire loosening shaft 2 and drives the wire clamp 3 to operate.

[0034] The first bending portion 621 includes a connecting portion 6211 and an extending portion 6212, wherein the connecting portion 6211 is perpendicular to the extending portion 6212, and the second bending portion 622 is disposed at the end of the extending portion 6212. The extending portion 6212 extends rightward, so that the second bending portion 622 can be connected to the loosening shaft 2.

[0035] The end surface of the second bending portion 622 facing the loosening shaft 2 is a guide surface 6221, and the guide surface 6221 is an arc-shaped inclined surface, that is, the inclined surface is an inclined arc surface. The width of the lower end of the second bending portion 622 is smaller than the width of its upper end. The guide surface 6221 is used to move the loosening shaft 2 to make axial movement.

[0036] The lifting plate 4 is an integrated type, and includes a first connecting rod portion 41 and a second connecting rod portion 42. The first connecting rod portion 41 and the second connecting rod portion 42 intersect and are not on the same straight line. The upper end of the first connecting rod portion 41 is hinged to the presser foot lifting front lever sub-component 1, and the lever 5 is arranged at the intersection of the first connecting rod portion 41 and the second connecting rod portion 42. The first connecting portion 41 enables the lever 5 to be closer to the thread loosening plate 6, so as to avoid the first toggle portion 61 being too long, wasting materials and having an incompact structure.

[0037] The inner end of the loosening shaft 2 is provided with a boss 7 surrounding it, and the second driving part 62 abuts against the boss 7. The boss 7 extends the contact surface to facilitate the second driving part 62 to contact it, thereby facilitating the axial movement of the loosening shaft 2.

[0038] A manual toggle assembly 8 for driving the presser foot lifting front lever subassembly 1 to rotate is installed on the side of the presser foot lifting front lever subassembly 1. The manual toggle assembly 8 drives the presser foot lifting front lever subassembly 1 to swing under manual operation.

[0039] Example 2

[0040] The features of Example 2 are basically the same as those of Example 1, except that the guide surface 6621 can also be a linear inclined surface, that is, the inclined surface is an inclined plane.

[0041] Example 3

[0042] A sewing machine, comprising a thread loosening mechanism in embodiment 1 or 2.

Claims

1. A thread loosening mechanism, comprising a presser foot front lever subassembly (1), a thread loosening shaft (2) and a thread clamp (3), wherein the lower end of the presser foot front lever subassembly (1) is hingedly connected with a lifting plate (4), the thread loosening shaft (2) is connected to the thread clamp (3) and drives two thread clamping pieces of the thread clamp (3) to separate or close; characterized in that: A thread loosening plate (6) is hinged on the casing, and a lever (5) is fixed on the lifting plate (4). One end of the thread loosening plate (6) is a first lever part (61), and the other end is a second lever part (62). The lever (5) abuts against the first lever part (61) and drives it to swing. When the thread loosening plate (6) swings, the first lever part (61) is connected to the thread loosening shaft (2) and drives it to move axially.

2. A wire loosening mechanism according to claim 1, characterized in that: The first toggle part (61) comprises an upper toggle rod (611) and a lower toggle rod (612), a channel (613) is provided between the upper toggle rod (611) and the lower toggle rod (612), and the toggle rod (5) passes through the channel (613) and is connected to the first toggle part (61).

3. A wire loosening mechanism according to claim 1, characterized in that: The second driving portion (62) comprises a first bending portion (621) and a second bending portion (622), wherein the first bending portion (621) is bent forward on the main body of the wire loosening plate (6), and the second bending portion (622) is bent upward on the first bending portion (621), and the second bending portion (622) is connected to the wire loosening shaft (2) and drives the wire clamp (3) to move.

4. A wire loosening mechanism according to claim 3, characterized in that: The first bending portion (621) comprises a connecting portion (6211) and an extending portion (6212), the connecting portion (6211) is perpendicular to the extending portion (6212), and the second bending portion (622) is arranged at the end of the extending portion (6212).

5. A wire loosening mechanism according to claim 3, characterized in that: The end surface of the second bent portion (622) facing the wire loosening shaft (2) is a guide surface (6221), the guide surface (6221) is an inclined surface, and the width of the lower end of the second bent portion (622) is smaller than the width of the upper end.

6. A wire loosening mechanism according to claim 5, characterized in that: The guide surface (6221) is an arc-shaped inclined surface.

7. A wire loosening mechanism according to any one of claims 1 to 6, characterized in that: The lifting plate (4) is an integrated type, comprising a first connecting rod portion (41) and a second connecting rod portion (42), wherein the first connecting rod portion (41) and the second connecting rod portion (42) intersect and are not on the same straight line, the upper end of the first connecting rod portion (41) is hinged to the presser foot lifting front lever sub-component (1), and the shifting rod (5) is arranged at the intersection of the first connecting rod portion (41) and the second connecting rod portion (42).

8. The wire loosening mechanism according to claim 1, characterized in that: The inner end of the loosening shaft (2) is provided with a boss (7) surrounding the inner end, and the second shifting portion (62) abuts against the boss (7).

9. A wire loosening mechanism according to claim 1, characterized in that: A manual toggle assembly (8) for driving the presser foot front lever subassembly (1) is installed on the side of the presser foot front lever subassembly (1) to rotate.

10. A sewing machine, characterized in that: A wire loosening mechanism comprising any one of claims 1-9.

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