Automatic presser foot lifting structure of sewing machine head

Abstract

The utility model provides an automatic presser foot lifting structure of a sewing machine head, and belongs to the technical field of sewing machines. The automatic presser foot lifting structure solves the problem that an existing automatic presser foot lifting structure is large in vibration and noise. According to the automatic presser foot lifting structure of the sewing machine head, the sewing machine head comprises a machine shell, a driving piece is fixedly connected to the lower end of the machine shell, the automatic presser foot lifting structure comprises a right lever hinged to the machine shell, one end of the driving piece is hinged to the right end of the right lever, and a presser foot lifting assembly is hinged to the left end of the right lever. The automatic presser foot lifting structure further comprises a torsion spring, the right lever is provided with a supporting portion connected with one end of the driving piece, one end of the torsion spring is fixedly connected with the machine shell, and the other end of the torsion spring is hooked on the supporting portion. The automatic presser foot lifting structure of the sewing machine head can reduce accumulation of gaps among the right lever, the driving piece and the presser foot lifting assembly, and therefore the purpose of reducing vibration and noise of parts is achieved.

Description

Technical Field

[0001] The utility model belongs to the technical field of sewing machines and relates to an automatic presser foot lifting structure of a sewing machine head. Background Art

[0002] During the sewing process, the sewing machine automatically raises and lowers the presser foot, which facilitates the feeding and exit of fabric and the smooth progress of sewing operations, thereby simplifying the sewing efficiency of the sewing machine. An automatic presser foot lifter is arranged in the casing of the sewing machine head. The automatic presser foot lifter is pulled up and down by a combination of multiple pull rods, a left lever and a right lever. Therefore, the movement of multiple parts when lifting up and down will cause a lot of noise.

[0003] For example, Chinese patent application [authorization announcement number: CN113604986B] discloses a sewing machine, including a driving motor, a tooth lifting height adjustment driving member, a presser foot lifting driving member, a thread trimming driving member, a tooth lifting mechanism, a presser foot lifting mechanism, a thread trimming mechanism, a tooth lifting height adjustment transmission unit connected between the tooth lifting height adjustment driving member and the tooth lifting mechanism, a presser foot lifting transmission unit connected between the presser foot lifting driving member and the presser foot lifting mechanism, and a thread trimming transmission unit connected between the thread trimming driving member and the thread trimming mechanism. The presser foot lifting mechanism includes a right lever rotating around a fourth fixed fulcrum, a presser foot lifting rod, a left lever rotating around a fifth fixed fulcrum, a presser foot lifting plate, a pressure rod guide, and a pressure rod for installing the presser foot at the lower end. The presser foot lifting connecting rod is hinged to the right lever, and the two ends of the presser foot lifting rod are hinged to the right lever and the left lever respectively. The left lever is hinged to the presser foot lifting plate. A lifting hook is provided on the presser foot lifting plate, and a connecting protrusion engaged with the lifting hook is provided on the pressure rod guide. The pressure rod guide is fixed to the upper end of the pressure rod.

[0004] The above structure drives the left and right movement of the presser foot lifting rod by the swing of the right lever, and the movement of the presser foot lifting rod drives the swing of the left lever, and the swing of the left lever drives the movement of the presser foot lifting plate, so that the hook of the presser foot lifting plate is engaged with the connecting protrusion of the pressure rod guide frame, thereby lifting the presser foot lifter upward. When resetting, the presser foot lifter is reset downward by applying a downward force through the pressure foot spring at the upper end of the pressure rod. During the adjustment process, the right lever swings, and the right lever is only hinged to the casing through the hinge point. During the rotation process, it will generate greater vibration and noise, affecting the use environment of the automatic presser foot lifting mechanism. Utility Model Content

[0005] The purpose of the utility model is to solve the above problems in the existing technology and propose an automatic presser foot lifting structure for a sewing machine head. The technical problem to be solved by the utility model is: how to solve the problems of high vibration and noise in the existing automatic presser foot lifting structure.

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

[0007] A structure for automatically lifting the presser foot of a sewing machine head, the sewing machine head comprising a casing, the lower end of the casing being fixedly connected to a driving member, the automatic presser foot lifting structure comprising a right lever hinged on the casing, one end of the driving member being hinged to the right end of the right lever, the left end of the right lever being hinged to a presser foot lifting assembly, the driving member driving the rotation of the right lever causing the presser foot in the presser foot lifting assembly to move up and down, and the characteristic of the structure is that the automatic presser foot lifting structure further comprises a torsion spring, the right lever comprising a supporting portion connected to one end of the driving member, one end of the torsion spring being fixedly connected to the casing, the other end of the torsion spring being hooked on the supporting portion, and the torsion spring having a pressure to press the supporting portion downward.

[0008] Since the torsion spring acts on the right lever, it is located in the middle of the entire automatic presser foot lifter structure, which can reduce the accumulation of gaps between the right lever, the driving member and the presser foot lifter assembly, thereby reducing the vibration and noise of parts.

[0009] In the above-mentioned automatic presser foot lifting structure of the sewing machine head, the support portion is plate-shaped, the upper end surface of the support portion has a downwardly recessed clamping notch, and the other end of the torsion spring is hooked on the clamping notch.

[0010] By setting the clamping notch, the other end of the torsion spring can be stably hooked on the clamping notch, preventing the other end of the torsion spring from sliding out of the support part during movement, thereby improving the stability of the right lever reset.

[0011] In the above-mentioned automatic presser foot lifting structure of the sewing machine head, one end of the torsion spring is bent to form a limiting hook, and the limiting hook is hung on the supporting part and located in the clamping notch.

[0012] The provision of the limiting hook can further enhance the stability of the connection between the torsion spring and the support portion, and the stability of the connection can be enhanced by merely bending the end of the torsion spring and adopting a relatively simple structure.

[0013] In the above-mentioned automatic presser foot lifting structure of the sewing machine head, the right lever is connected to a hinge pin whose end is fixed to the casing, and the middle part of the torsion spring is sleeved on the hinge pin and pressed on the casing through the right lever.

[0014] The middle part of the torsion spring can also be sleeved on the hinge pin, and the hinge pin is the mounting component of the existing right lever. Therefore, the setting of the torsion spring is more stable, so that when the torsion spring is in action, it can stably control the right lever, thereby achieving the purpose of reducing vibration and noise.

[0015] In the above-mentioned automatic presser foot lifting structure of the sewing machine head, the driving part includes a push rod and a driving motor that drives the push rod to move up and down. The end of the support part is hinged to the push rod through a hinge shaft, and the limit hook is located between the hinge shaft and the hinge pin.

[0016] By locating the limit hook between the hinge shaft and the hinge pin, the setting of the limit hook will not affect the installation between the right lever and the top rod, and the installation between the right lever and the casing, thereby ensuring that the installation is not affected and improving the stability of the automatic presser foot lifting structure.

[0017] In the automatic presser foot lifting structure of the above-mentioned sewing machine head, the presser foot lifting assembly includes a presser foot lifting rod and a left lever hinged to the casing. The two ends of the presser foot lifting rod are hinged to the left lever and the right lever respectively. A waist-shaped hole is provided on the left lever, and a guide pin located in the waist-shaped hole is fixedly connected to the casing. When the left lever swings, the guide pin can slide relatively along the waist-shaped hole.

[0018] The left lever type realizes the stroke limit of the left lever through the cooperation of the waist-shaped hole and the guide pin, so that both the left lever and the right lever can swing stably, thereby improving the stability of the automatic presser foot lifting structure.

[0019] Compared with the existing technology, the automatic presser foot lifting structure of the sewing machine head has the following advantages: a torsion spring is fixedly connected to the machine casing, and the other end of the torsion spring is hooked on the support part of the right lever. At this time, the torsion spring always has the pressure to press the support part downward. When the presser foot needs to be reset, the downward pressure of the torsion spring on the support part can be used to quickly reset the right lever. Since the torsion spring acts on the right lever and is located in the middle of the entire automatic presser foot lifting structure, the accumulation of gaps between the right lever and the driving part and the presser foot lifting assembly can be reduced, thereby achieving the purpose of reducing the vibration and noise of the parts. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a schematic structural diagram of the utility model after assembly.

[0021] Figure 2 It is a partial structural diagram of the utility model.

[0022] In the figure, 1. driving part; 11. push rod; 12. driving motor; 2. right lever; 21. supporting part; 21a. snap-fit ​​notch; 22. hinge pin; 23. hinge shaft; 3. presser foot lifting assembly; 31. presser foot lifting; 32. presser foot lifting rod; 33. left lever; 33a. waist-shaped hole; 4. torsion spring; 41. limit hook; 5. guide pin. DETAILED DESCRIPTION

[0023] The following are specific embodiments of the present invention and the accompanying drawings to further describe the technical solution of the present invention, but the present invention is not limited to these embodiments.

[0024] like Figure 1 As shown, the automatic presser foot lifting structure of the sewing machine head includes a casing, a driving member 1 is fixedly connected to the lower end of the casing, and the automatic presser foot lifting structure includes a right lever 2 hinged on the casing.

[0025] Specifically, if Figure 1 and Figure 2 As shown, one end of the driving member 1 is hinged to the right end of the right lever 2, and the left end of the right lever 2 is hinged to the presser foot lifting assembly 3. The driving member 1 drives the right lever 2 to rotate so that the presser foot lifting 31 in the presser foot lifting assembly 3 moves up and down. This automatic presser foot lifting structure also includes a torsion spring 4. The right lever 2 has a support portion 21 connected to one end of the driving member 1, one end of the torsion spring 4 is fixedly connected to the casing, and the other end of the torsion spring 4 is hooked on the support portion 21, and the torsion spring 4 has a pressure to press the support portion 21 downward.

[0026] When the cam 2 is in the upright position, the left end of the cam 2 is rotated by the right lever 2, and the right lever 2 is rotated by the right lever 2. When the cam 2 is in the upright position, the right lever 2 is rotated by the right lever 2, and the left end of the cam 2 is rotated by the right lever 2. When the cam 2 is in the upright position, the right lever 2 is rotated by the right lever 2, and the right lever 2 is rotated by the right lever 2. When the cam 2 is in the upright position, the right lever 2 is rotated by the right lever 2

[0027] like Figure 2As shown, the support portion 21 is plate-shaped, and the upper end surface of the support portion 21 has a downwardly concave snap-fit ​​notch 21a. The other end of the torsion spring 4 is hooked on the snap-fit ​​notch 21a, and one end of the torsion spring 4 is bent to form a limiting hook 41. The limiting hook 41 is hung on the support portion 21 and is located in the snap-fit ​​notch 21a. The right lever 2 is connected to a hinge pin 22 whose end is fixed to the casing. The middle part of the torsion spring 4 is sleeved on the hinge pin 22 and pressed on the casing through the right lever 2.

[0028] like Figure 1 and Figure 2 As shown, the driving member 1 includes a push rod 11 and a driving motor 12 that drives the push rod 11 to move up and down. The end of the support part 21 is hinged to the push rod 11 through a hinge shaft 23. The limit hook 41 is located between the hinge shaft 23 and the hinge pin 22. The presser foot lifting assembly 3 includes a presser foot lifting rod 32 and a left lever 33 hinged to the casing. The two ends of the presser foot lifting rod 32 are hinged to the left lever 33 and the right lever 2 respectively. A waist-shaped hole 33a is provided on the left lever 33. A guide pin 5 located in the waist-shaped hole 33a is fixed to the casing. When the left lever 33 swings, the guide pin 5 can slide relatively along the waist-shaped hole 33a.

[0029] The specific embodiments described herein are merely illustrative of the spirit of the present invention. Persons skilled in the art may make various modifications, additions, or substitutions to the described specific embodiments without departing from the spirit of the present invention or exceeding the scope defined by the appended claims.

Claims

1. An automatic presser foot lifting structure for a sewing machine head, the sewing machine head includes a housing, the lower end of the housing is fixedly connected to a driving member (1), the automatic presser foot lifting structure includes a right lever (2) hinged on the housing, one end of the driving member (1) is hinged to the right end of the right lever (2), the left end of the right lever (2) is hinged to a presser foot lifting assembly (3), the driving member (1) drives the right lever (2) to rotate so that the presser foot lifting (31) in the presser foot lifting assembly (3) moves up and down, and is characterized in that The automatic presser foot lifting structure further comprises a torsion spring (4), the right lever (2) having a support portion (21) connected to one end of the driving member (1), one end of the torsion spring (4) being fixedly connected to the housing, the other end of the torsion spring (4) being hooked on the support portion (21), and the torsion spring (4) having a pressure for pressing the support portion (21) downward.

2. The automatic presser foot lifting structure of the sewing machine head according to claim 1, characterized in that: The support portion (21) is plate-shaped, and the upper end surface of the support portion (21) has a downwardly recessed clamping notch (21a), and the other end of the torsion spring (4) is hooked on the clamping notch (21a).

3. The automatic presser foot lifting structure of the sewing machine head according to claim 2, characterized in that: One end of the torsion spring (4) is bent to form a limiting hook (41), and the limiting hook (41) is hung on the support portion (21) and located in the clamping notch (21a).

4. The automatic presser foot lifting structure of the sewing machine head according to claim 2 or 3, characterized in that: The right lever (2) is connected to a hinge pin (22) whose end is fixed to the housing. The middle part of the torsion spring (4) is sleeved on the hinge pin (22) and pressed on the housing through the right lever (2).

5. The automatic presser foot lifting structure of the sewing machine head according to claim 4, characterized in that: The driving member (1) comprises a push rod (11) and a driving motor (12) for driving the push rod (11) to move up and down; the end of the supporting portion (21) is hinged to the push rod (11) via a hinge shaft (23); and the limiting hook (41) is located between the hinge shaft (23) and the hinge pin (22).

6. The automatic presser foot lifting structure of a sewing machine head according to claim 1, 2 or 3, characterized in that: The presser foot lifting assembly (3) comprises a presser foot lifting rod (32) and a left lever (33) hinged to the housing. The two ends of the presser foot lifting rod (32) are hinged to the left lever (33) and the right lever (2) respectively. A waist-shaped hole (33a) is provided on the left lever (33). A guide pin (5) located in the waist-shaped hole (33a) is fixedly connected to the housing. When the left lever (33) swings, the guide pin (5) can slide relatively along the waist-shaped hole (33a).

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