Automatic presser foot lifting height rapid adjusting structure of sewing machine head

Abstract

The utility model provides an automatic presser foot lifting height rapid adjusting structure of a sewing machine head, and belongs to the technical field of sewing machines. The problem that an existing presser foot lifting height adjusting structure occupies a large space in a machine shell is solved. According to the automatic presser foot lifting height rapid adjusting structure of the sewing machine head, a sewing machine comprises a machine shell and a presser foot lifting shaft which is arranged in the machine shell in a penetrating mode and can rotate, an adjusting block is fixed to the presser foot lifting shaft, the adjusting block is provided with an abutting portion, the presser foot lifting height rapid adjusting structure comprises an adjusting rod arranged on the machine shell in a penetrating mode, and the adjusting rod is in threaded connection with the machine shell. The outer end of the adjusting rod is located outside the machine shell, the inner end of the adjusting rod is located in the machine shell, the adjusting rod is perpendicular to the presser foot lifting shaft, and the abutting portion can abut against the inner end of the adjusting rod. According to the automatic presser foot lifting height rapid adjusting structure of the sewing machine head, the occupied space of the presser foot lifting height adjusting structure in the machine shell is reduced, other parts in the machine shell can be arranged more compactly, the manufacturing cost is reduced, and assembling is convenient.

Description

Technical Field

[0001] The utility model belongs to the technical field of sewing machines, and relates to a rapid adjustment structure for automatically adjusting the height of the presser foot of a sewing machine head. Background Art

[0002] During the sewing process of a sewing machine, feeding and sewing are usually achieved by lifting the presser foot in cooperation with the feed dog or the needle plate. The height of the existing automatic presser foot is fixed and non-adjustable, and the driving source of the presser foot is usually an electromagnet.

[0003] For example, Chinese Patent Application [Authorized Publication No.: CN209082139U] discloses a presser foot height adjustment device, which includes a sleeve. A sliding rod that can move in the vertical direction is arranged inside the sleeve. The lower end of the sliding rod is hinged with a pull rod, and the end of the pull rod away from the sliding rod is used for hinging with the rear lever of the presser foot of the sewing machine. The sleeve is also provided with a limiting part for adjusting the moving range of the sliding rod.

[0004] When the above-mentioned electromagnet drives the presser foot, the movement stroke of the electromagnet core is a fixed value. When the electromagnet acts, the presser foot can only be lifted to the highest point at one time, and cannot be lifted to any height below the highest point, that is, the height of the presser foot is non-adjustable; moreover, due to the movement nature of the electromagnet, there will be a large impulse during the lifting process of the presser foot, and it is also difficult to control the buffer when the presser foot is lowered. Therefore, the impact force during the lifting and lowering of the presser foot is relatively large, generating relatively large noise and vibration. Since there are a large number of components inside the sewing machine housing, and components such as electromagnets occupy a relatively large space inside the sewing machine housing, it is not conducive to the compact arrangement of components and is likely to cause interference to the arrangement of other components. Content of the Utility Model

[0005] The purpose of the present utility model is to address the above problems existing in the prior art and propose a rapid adjustment structure for automatically adjusting the height of the presser foot of a sewing machine head. The technical problem to be solved by the present utility model is: how to solve the problem that the existing presser foot height adjustment structure occupies a large space inside the machine housing.

[0006] The purpose of the present utility model can be achieved by the following technical solutions:

[0007] A rapid adjustment structure for automatically adjusting the height of the presser foot of a sewing machine head. The sewing machine includes a machine housing and a presser foot shaft that is inserted into the machine housing and can rotate. It is characterized in that an adjustment block is fixed on the presser foot shaft, and the adjustment block has an abutting portion. The rapid adjustment structure for the presser foot height includes an adjustment rod inserted through the machine housing. The adjustment rod is threadedly connected to the machine housing. The outer end of the adjustment rod is located outside the machine housing, and the inner end of the adjustment rod is located inside the machine housing. The adjustment rod is perpendicular to the presser foot shaft, and the abutting portion can abut against the inner end of the adjustment rod.

[0008] The driving part inside the machine shell drives the presser foot lifting shaft to rotate, and then drives the presser foot to lift upward. Specifically, when the presser foot lifting shaft rotates, the adjusting block swings synchronously with the presser foot lifting shaft. When the presser foot lifting shaft rotates a certain angle, the adjusting rod is perpendicular to the presser foot lifting shaft, and the abutting part can abut against the inner end of the adjusting rod through the rotation of the presser foot lifting shaft, thereby restricting the rotation of the presser foot lifting shaft. At this time, the presser foot is lifted to a certain height. When it is necessary to adjust the maximum lifting height of the presser foot, rotate the adjusting rod so that the inner end of the adjusting rod approaches or moves away from the abutting part. When the inner end of the adjusting rod approaches the abutting part, the rotation angle of the presser foot lifting shaft is smaller, and thus the maximum lifting height of the presser foot is lower. When the inner end of the adjusting rod moves away from the abutting part, the rotation angle of the presser foot lifting shaft is larger, and thus the maximum lifting height of the presser foot is higher. In this structure, only one adjusting rod is provided on the machine shell, and the maximum lifting height of the presser foot is adjusted by the way that the abutting part abuts against the inner end of the adjusting rod. The inner end of the adjusting rod can serve as a limiting part, and there is no need to set an adjusting cam inside the machine shell, which significantly reduces the occupied space of the presser foot lifting height adjusting structure inside the machine shell, is beneficial to the more compact arrangement of other components inside the machine shell, reduces the manufacturing cost at the same time, and is convenient for assembly.

[0009] In the above-mentioned automatic presser foot height rapid adjustment structure of a sewing machine head, a threaded hole is provided on the machine shell, and a locking nut is threadedly connected to the adjusting rod. The adjusting rod is threadedly connected in the threaded hole, and the locking nut threadedly locks the adjusting rod on the machine shell. An internal hexagonal hole is provided on the outer end face of the adjusting rod.

[0010] A threaded hole is directly provided on the machine shell, the adjusting rod is threadedly connected to the machine shell, and the position of the adjusting rod can be adjusted by rotation. After adjustment, the adjusting rod is pressed on the machine shell by the locking nut to realize the locking and fixing of the adjusting rod, and the threaded connection between the adjusting rod and the machine shell can be realized. The setting of the internal hexagonal hole facilitates the use of a hexagonal wrench to rotate the adjusting rod, thereby realizing the adjustment of the lifting height of the presser foot.

[0011] In the above-mentioned automatic presser foot height rapid adjustment structure of a sewing machine head, the presser foot height rapid adjustment structure includes a rotating shaft provided inside the machine shell and perpendicular to the presser foot lifting shaft. The outer end of the rotating shaft is located outside the machine shell, and the inner end of the rotating shaft is located inside the machine shell. A presser foot handle is fixed to the outer end of the rotating shaft, an adjusting cam is fixed to the inner end of the rotating shaft, the adjusting block has a sliding part that contacts the curved surface of the adjusting cam, and a torsion spring is sleeved on the presser foot lifting shaft. One end of the torsion spring is hooked on the abutting part.

[0012] This structure manually raises the presser foot. By pressing the presser foot lifting handle, the presser foot lifting handle drives the rotating shaft to rotate. After the rotating shaft rotates, it drives the adjusting cam to rotate. The adjusting cam rotates vertically to push the sliding part upward, thereby driving the adjusting block to swing. The adjusting block and the presser foot shaft rotate synchronously, thereby realizing the raising of the presser foot. When the abutting part abuts against the inner end of the adjusting rod, the presser foot reaches the maximum lifting height at this time; after releasing the presser foot lifting handle, under the action of the torsion spring, the presser foot shaft automatically rotates and resets, and the presser foot automatically moves downward.

[0013] In the above-mentioned automatic presser foot height rapid adjustment structure of a sewing machine head, the sliding part has an arc surface, and the arc surface is tangent to the curved surface of the adjusting cam.

[0014] The sliding part and the adjusting cam are in line contact, so that the friction between the sliding part and the adjusting cam is small, and the adjustment of the lifting height of the presser foot is smoother.

[0015] In the above-mentioned automatic presser foot height rapid adjustment structure of a sewing machine head, a swing rod is fixed to the rear end of the presser foot shaft, an adjusting cylinder is arranged in the machine shell, and the outer end of the piston rod of the adjusting cylinder is hinged to the outer end of the swing rod.

[0016] When the adjusting cylinder acts, the adjusting cylinder drives the swing rod to swing. After the swing rod swings, it drives the presser foot shaft to rotate, thereby raising the presser foot. This structure realizes the automatic raising of the presser foot through the adjusting cylinder.

[0017] In the above-mentioned automatic presser foot height rapid adjustment structure of a sewing machine head, a presser foot assembly is arranged on the machine shell, and a lifting crank for lifting the presser foot assembly upward is fixed to the front end of the presser foot shaft.

[0018] When the presser foot shaft rotates, the lifting crank raises the presser foot assembly upward, thereby realizing the raising of the presser foot.

[0019] Compared with the prior art, the automatic presser foot height rapid adjustment structure of the sewing machine head of the present utility model has the following advantages: This structure only sets an adjusting rod on the machine shell, and adopts the method of abutting the abutting part against the inner end of the adjusting rod to adjust the lifting height of the presser foot. The inner end of the adjusting rod can serve as the limiting part, and there is no need to set an adjusting cam in the machine shell, which significantly reduces the occupied space of the presser foot lifting height adjustment structure in the machine shell, is beneficial to the more compact arrangement of other components in the machine shell, and at the same time reduces the manufacturing cost and is convenient for assembly. Brief Description of the Drawings

[0020] Figure 1 is one of the three-dimensional structure schematic diagrams of the present utility model.

[0021] Figure 2 is the second three-dimensional structure schematic diagram of the present utility model.

[0022] Figure 3 It is a three-dimensional structural schematic diagram of the adjusting rod and the locking nut of the present utility model.

[0023] Figure 4 It is a three-dimensional structural schematic diagram of the machine housing of the present utility model.

[0024] Figure 5 It is a partial three-dimensional structural schematic diagram of the present utility model.

[0025] Figure 6 It is a three-dimensional structural schematic diagram of the adjusting block of the present utility model.

[0026] Figure 7 It is the third three-dimensional structural schematic diagram of the present utility model.

[0027] In the figure, 1. Machine housing; 2. Lifting presser foot shaft; 3. Adjusting block; 31. Sliding part; 310. Arc surface; 30. Abutting part; 4. Adjusting rod; 40. Outer end; 41. Inner end; 42. Inner hexagonal hole; 5. Threaded hole; 6. Locking nut; 7. Rotating shaft; 8. Lifting presser foot handle; 9. Adjusting cam; 90. Curved surface; 10. Torsion spring; 11. Swing rod; 12. Adjusting cylinder; 13. Presser foot assembly; 14. Lifting crank. Specific embodiments

[0028] The following are specific embodiments of the present utility model and in conjunction with the accompanying drawings, the technical solutions of the present utility model will be further described, but the present utility model is not limited to these embodiments.

[0029] As Figures 1 to 6 shown, the automatic lifting presser foot height rapid adjustment structure of the sewing machine head of the present utility model includes a machine housing 1 and a lifting presser foot shaft 2 that is arranged in the machine housing 1 and can rotate. A presser foot assembly 13 is arranged on the machine housing 1, and a lifting crank 14 for lifting the presser foot assembly 13 upward is fixed at the front end of the lifting presser foot shaft 2. An adjusting block 3 is fixed on the lifting presser foot shaft 2. The adjusting block 3 has an abutting part 30. The present lifting presser foot height rapid adjustment structure further includes an adjusting rod 4 that is arranged on the machine housing 1. The adjusting rod 4 is threadedly connected to the machine housing 1. The outer end 40 of the adjusting rod 4 is located outside the machine housing 1, and the inner end 41 of the adjusting rod 4 is located inside the machine housing 1. The adjusting rod 4 is vertically arranged with the lifting presser foot shaft 2, and the abutting part 30 can abut against the inner end 41 of the adjusting rod 4. In this embodiment, a threaded hole 5 is opened on the machine housing 1, a locking nut 6 is threadedly connected to the adjusting rod 4, the adjusting rod 4 is threadedly connected in the threaded hole 5, and the locking nut 6 threadedly locks the adjusting rod 4 on the machine housing 1. An inner hexagonal hole 42 is opened on the outer end surface of the adjusting rod 4.

[0030] The driving part inside the casing drives the presser foot lifting shaft 2 to rotate, which then drives the presser foot to lift upward. Specifically, when the presser foot lifting shaft 2 rotates, the adjusting block 3 rotates synchronously with the presser foot lifting shaft 2. When the presser foot lifting shaft 2 rotates by a certain angle, the abutting part 30 abuts against the inner end of the adjusting rod 4, thereby restricting the rotation of the presser foot lifting shaft 2. At this time, the presser foot is lifted by a certain height. When it is necessary to adjust the lifting height of the presser foot, rotate the adjusting rod 4 so that the inner end 41 of the adjusting rod 4 approaches or moves away from the abutting part. When the inner end 41 of the adjusting rod 4 approaches the abutting part 30, the rotation angle of the presser foot lifting shaft 2 is smaller, and thus the lifting height of the presser foot is lower. When the inner end 41 of the adjusting rod 4 moves away from the abutting part 30, the rotation angle of the presser foot lifting shaft 2 is larger, and thus the lifting height of the presser foot is higher. In this structure, only one adjusting rod 4 is provided on the casing 1, and the abutting part 30 abuts against the inner end 41 of the adjusting rod 4 to adjust the lifting height of the presser foot. The inner end 41 of the adjusting rod 4 can serve as a limiting part, and there is no need to set an adjusting cam inside the casing 1, which significantly reduces the occupied space of the presser foot lifting height adjusting structure inside the casing 1, is beneficial to the more compact arrangement of other components inside the casing 1, and also reduces the manufacturing cost and facilitates assembly.

[0031] Further, as Figures 1 - 5 shown, this rapid presser foot height adjusting structure further includes a rotating shaft 7 disposed inside the casing 1 and perpendicular to the presser foot lifting shaft 2. The outer end of the rotating shaft 7 is located outside the casing 1, and the inner end of the rotating shaft 7 is located inside the casing 1. A presser foot handle 8 is fixed to the outer end of the rotating shaft 7, and an adjusting cam 9 is fixed to the inner end of the rotating shaft 7. The adjusting block 3 has a sliding part 31 that contacts the curved surface 90 of the adjusting cam 9. In this embodiment, the sliding part 31 has an arc surface 310, and the arc surface 310 is tangent to the curved surface 90 of the adjusting cam 9. A torsion spring 10 is sleeved on the presser foot lifting shaft 2, and one end of the torsion spring 10 is hooked on the abutting part 30. This structure manually lifts the presser foot. By pressing the presser foot handle 8, the presser foot handle 8 drives the rotating shaft 7 to rotate. After the rotating shaft 7 rotates, it drives the adjusting cam 9 to rotate. The adjusting cam 9 rotates vertically to push the sliding part 31 upward, thereby driving the adjusting block 3 to swing. The adjusting block 3 and the presser foot lifting shaft 2 rotate synchronously, thereby realizing the lifting of the presser foot. When the abutting part 30 abuts against the inner end 41 of the adjusting rod 4, the presser foot is at the maximum lifting height at this time; after releasing the presser foot handle 8, under the action of the torsion spring 10, the presser foot lifting shaft 2 automatically rotates and resets, and the presser foot automatically moves downward.

[0032] As Figure 5 and Figure 7 shown, a swing rod 11 is fixed to the rear end of the presser foot lifting shaft 2, and an adjusting cylinder 12 is disposed inside the casing 1. The outer end of the piston rod of the adjusting cylinder 12 is hinged to the outer end of the swing rod 11. When the adjusting cylinder 12 acts, the adjusting cylinder 12 drives the swing rod 11 to swing. After the swing rod 11 swings, it drives the presser foot lifting shaft 2 to rotate, thereby lifting the presser foot. This structure realizes the automatic lifting of the presser foot through the adjusting cylinder 12.

[0033] The specific embodiments described herein are merely illustrative of the spirit of the present utility model. Those skilled in the art to which the present utility model pertains can make various modifications or supplements to the described specific embodiments or use similar ways for substitution, but will not deviate from the spirit of the present utility model or exceed the scope defined by the appended claims.

Claims

1. A structure for quickly adjusting the height of an automatic presser foot lifter of a sewing machine head, the sewing machine comprising a housing (1) and a presser foot lifter shaft (2) which is rotatably disposed in the housing (1), characterized in that: The presser foot lifting shaft (2) is fixed with an adjustment block (3), and the adjustment block (3) has a supporting portion (30). The presser foot lifting height quick adjustment structure comprises an adjustment rod (4) inserted into the casing (1), the adjustment rod (4) is threadedly connected to the casing (1), the outer end (40) of the adjustment rod (4) is located outside the casing (1), and the inner end (41) of the adjustment rod (4) is located inside the casing (1). The adjustment rod (4) is vertically arranged with the presser foot lifting shaft (2), and the supporting portion (30) can be supported against the inner end (41) of the adjustment rod (4).

2. The automatic presser foot height quick adjustment structure of a sewing machine head according to claim 1, characterized in that: The housing (1) is provided with a threaded hole (5), the adjusting rod (4) is threadedly connected with a locking nut (6), the adjusting rod (4) is threadedly connected in the threaded hole (5), and the locking nut (6) threadably locks the adjusting rod (4) on the housing (1), and the outer end surface of the adjusting rod (4) is provided with a hexagonal hole (42).

3. The automatic presser foot height quick adjustment structure of a sewing machine head according to claim 1 or 2, characterized in that: The presser foot lifting height quick adjustment structure also includes a rotating shaft (7) arranged in the casing (1) and perpendicular to the presser foot lifting shaft (2), the outer end of the rotating shaft (7) is located outside the casing (1), and the inner end of the rotating shaft (7) is located inside the casing (1), a presser foot lifting handle (8) is fixed to the outer end of the rotating shaft (7), and an adjustment cam (9) is fixed to the inner end of the rotating shaft (7), the adjustment block (3) has a sliding portion (31) in contact with a curved surface (90) of the adjustment cam (9), and the presser foot lifting shaft (2) is sleeved with a torsion spring (10), one end of which is hooked on the abutment portion (30).

4. The automatic presser foot height quick adjustment structure of a sewing machine head according to claim 3, characterized in that: The sliding portion (31) has an arc surface (310), and the arc surface (310) is tangent to the curved surface (90) of the adjusting cam (9).

5. The automatic presser foot height quick adjustment structure of a sewing machine head according to claim 1 or 2, characterized in that: A swing rod (11) is fixed to the rear end of the presser foot lifting shaft (2), an adjusting cylinder (12) is arranged in the housing (1), and the outer end of the piston rod of the adjusting cylinder (12) is hinged to the outer end of the swing rod (11).

6. The automatic presser foot height quick adjustment structure of a sewing machine head according to claim 1 or 2, characterized in that: The housing (1) is provided with a presser foot assembly (13), and a lifting crank (14) for lifting the presser foot assembly (13) upwards is fixed to the front end of the presser foot lifting shaft (2).

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