Knee leaning presser foot lifting mechanism and sewing machine

Abstract

The utility model belongs to the technical field of sewing machines, and particularly relates to a knee rest presser foot lifting mechanism and a sewing machine. The presser foot assembly comprises a presser foot transmission crank and a presser foot part, and the presser foot transmission crank is rotationally arranged on the base; the output end of the motor driving assembly is movably connected with the front end of the presser foot transmission crank in an abutting mode, and the knee rest driving assembly is characterized by further comprising a knee rest driving assembly, a knee rest driving assembly and a knee rest driving assembly, and the output end of the knee rest driving assembly is movably connected with the rear end of the presser foot transmission crank in an abutting mode; the output end of the motor driving assembly and the output end of the knee rest driving assembly are used for pushing the presser foot transmission crank to rotate, and the presser foot transmission crank rotates to achieve ascending and descending of the presser foot part. The knee rest driving assembly comprises a power input part and a power output part, wherein the power input part comprises a knee rest plate and a knee rest connecting shaft; the power transmission part comprises a knee leaning shaft pin and a knee leaning rotating shaft, and the knee leaning rotating shaft is rotationally arranged on the base; the power output part comprises a knee rest crank and a knee rest ball; and the knee rest reset spring is arranged on the knee rest rotating shaft in a sleeving manner.

Description

Technical Field

[0001] The present technical solution relates to the technical field of sewing machines, and in particular to a knee-rest presser foot lifting mechanism and a sewing machine. Background Art

[0002] A sewing machine is a machine that uses one or more sewing threads to form one or more stitches on the sewing material, so that one or more layers of sewing materials are interwoven or sewn together. Sewing machines can sew fabrics such as cotton, linen, silk, wool, and synthetic fibers, as well as products such as leather, plastic, and paper. The stitches are neat, beautiful, flat, and firm, and the sewing speed is fast and easy to use. The presser foot is an important part of the sewing machine. The sewing machine needs to lift the presser foot during the working process. Currently, there are two operating modes for lifting the presser foot on the sewing machine: manual and automatic. The manual presser foot lifting method is to manually drive the corresponding manual transmission mechanism to lift the presser foot, and the automatic presser foot lifting method uses electric components such as electromagnets, motors, etc. as power sources to drive the corresponding automatic transmission mechanism to lift the presser foot.

[0003] Chinese patent CN116446116A discloses a sewing machine, which drives a thread trimming mechanism, a presser foot lifting mechanism and a stitch length adjusting mechanism by a motor, and the technical solution is relatively compact; in this technical solution, a knee presser foot lifting mechanism is not integrated; at the same time, Chinese patent CN109629127A discloses a knee presser foot lifting device of a sewing machine, and this knee presser foot lifting device has the following disadvantages:

[0004] 1. The knee rest plate controls the lifting of the small presser foot through the jacking long rod and the lifting rod, and the connection between the lifting long rod and the lifting rod is far away from the knee rest plate. Therefore, the limit frame can only drive the lifting rod through the jacking long rod, and the jacking long rod is a very long, vertically arranged rod, and the electromagnet is connected to the rear end of the lifting rod through the presser foot lifting rod, which makes the knee rest plate and the electromagnet far away. The positions of the two in the sewing machine determine the size of the sewing machine. Therefore, this sewing machine is large in size and poor in space utilization.

[0005] 2. The knee-rest presser foot lifting device has many parts and a complex structure, and it is time-consuming and laborious to install it on the sewing machine.

[0006] Therefore, the applicant intends to further develop a sewing machine with a simplified structure and a knee-rest presser foot lifting mechanism based on the technology of the sewing machine in Chinese patent CN116446116A. Summary of the invention

[0007] The purpose of this technical solution is to provide a knee-rest presser foot lifting mechanism, which receives power provided by a motor drive assembly or a knee-rest drive assembly through a presser foot transmission crank to achieve the lifting and lowering of the presser foot, thereby solving the problem of control interference of the existing presser foot lifting mechanism.

[0008] The purpose of this technical solution is achieved in this way:

[0009] A knee-rest presser foot lifting mechanism comprises: a base; a presser foot assembly, which comprises a presser foot transmission crank and a presser foot part, the presser foot transmission crank is rotatably arranged on the base; and a motor drive assembly, the output end of which movably abuts against the front end of the presser foot transmission crank, characterized in that it also comprises:

[0010] A knee rest driving assembly, whose output end movably abuts against the rear end of the presser foot transmission crank; wherein the output ends of the motor driving assembly and the knee rest driving assembly are respectively used to drive the presser foot transmission crank to rotate, and the presser foot transmission crank realizes the lifting and lowering of the presser foot part by rotating.

[0011] Preferably, the knee rest driving assembly comprises: a power input portion, which comprises a knee rest plate and a knee rest connecting shaft arranged on the knee rest plate; a power transmission portion, which comprises a knee rest axle pin and a knee rest rotating shaft connected to the knee rest axle pin, and the knee rest rotating shaft is rotatably arranged on the base; a power output portion, which comprises a knee rest crank and a knee rest ball arranged on the knee rest crank; and a knee rest reset spring, which is sleeved on the knee rest rotating shaft, and its two ends are respectively fixed on the base and the knee rest crank; wherein, the knee rest connecting shaft and the knee rest axle pin are connected, and the knee rest crank is arranged at the front end of the knee rest rotating shaft, and the knee rest ball can be driven to approach and push the presser foot transmission crank to rotate by pushing the knee rest plate; the spherical surface of the knee rest ball cooperates with the rear end of the presser foot transmission crank.

[0012] Preferably, the knee rest axis pin is connected via a knee rest joint and a knee rest connecting shaft; the knee rest axis pin and the knee rest connecting shaft are plugged into different side walls of the knee rest joint.

[0013] Preferably, a shaft connecting groove is provided at the front end of the knee rest shaft pin, the shaft connecting groove has a locking groove, and a shaft connecting pin is inserted on the knee rest shaft; when the knee rest shaft is connected to the knee rest shaft pin, the shaft connecting pin is clamped in the shaft connecting groove; when the knee rest shaft rotates, the shaft connecting pin enters and is clamped in the locking groove.

[0014] Preferably, a locking piece is provided on the knee rest shaft, and the locking piece movably abuts against the base.

[0015] Preferably, two mounting parts are formed on the base, and both ends of the knee rest shaft are inserted into the mounting holes opened on the mounting parts; the knee rest crank and the knee rest return spring are both located between the two mounting parts; one end of the knee rest return spring is inserted into the mounting part close to the knee rest shaft pin.

[0016] Preferably, an oil box is provided on the lower side of the base, and the two mounting parts are provided on the side wall of the oil box; the knee rest shaft pin and the knee rest shaft are arranged along the cloth feeding direction; the knee rest shaft extends toward the position of the presser foot transmission crank, and the knee rest crank is fixed on the knee rest shaft, and the working plane of the knee rest crank is perpendicular to the axial direction of the knee rest shaft; the knee rest ball is arranged at the swing end of the knee rest crank and is located on the lower side of the rear end of the presser foot transmission crank.

[0017] Preferably, the presser foot transmission crank is rotatably arranged on the base through a presser foot crank rod; the presser foot transmission crank has abutment end one at the rear end and abutment end two at the front end, and the presser foot crank rod is simultaneously inserted into abutment end one and abutment end two; the knee rest ball movably abuts abutment end one; the output end of the motor drive assembly movably abuts abutment end two.

[0018] Preferably, a presser foot reset spring is arranged on the presser foot crank rod; two ends of the presser foot reset spring are respectively fixed on the oil box and the second abutment end.

[0019] A sewing machine comprises a knee-rest presser foot lifting mechanism; further comprising a thread trimming mechanism, an electric-controlled presser foot lifting mechanism and a stitch length adjusting mechanism; the motor drive assembly comprises a first output end and a second output end, the first output end drives the electric-controlled presser foot lifting mechanism and the stitch length adjusting mechanism, and the second output end drives the thread trimming mechanism; the knee-rest presser foot lifting mechanism and the electric-controlled presser foot lifting mechanism share the presser foot transmission crank.

[0020] Compared with the prior art, the technical solution has the following outstanding and beneficial technical effects:

[0021] 1. The presser foot transmission crank designed in the present technical solution can receive power input from the motor drive assembly or the knee rest drive assembly, and the output ends of the motor drive assembly and the knee rest drive assembly are movably abutted against the two ends of the presser foot transmission crank, so when the sewing machine is working, the presser foot can be raised and lowered by manual or motor drive without control interference.

[0022] 2. The knee rest drive assembly designed in this technical solution has a simple structure and fast power transmission. When the knee rest plate is not subjected to force, the locking piece abuts against the base. At this time, the knee rest ball is away from the abutment end, which does not affect the control of the presser foot by the motor drive assembly. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is a schematic diagram of the structure of the technical solution installed on a sewing machine.

[0024] Figure 2 This is a structural diagram of the technical solution.

[0025] Figure 3 This is one of the structural schematic diagrams of the knee rest drive assembly.

[0026] Figure 4 This is the second structural diagram of the knee rest drive assembly.

[0027] Figure 5 This is the third structural diagram of the knee rest drive assembly.

[0028] Figure 6 An exploded view of the knee support drive assembly.

[0029] Figure 7 This is a schematic diagram of the structure of each mechanism in a sewing machine.

[0030] 1. Base; 2. Presser foot assembly; 3. Presser foot transmission crank; 4. Presser foot portion; 5. Motor drive assembly; 6. Knee rest drive assembly; 7. Power input portion; 8. Knee rest plate; 9. Knee rest connecting shaft; 10. Power transmission portion; 11. Knee rest shaft pin; 12. Knee rest rotating shaft; 13. Power output portion; 14. Knee rest crank; 15. Knee rest ball bearing; 16. Knee rest return spring; 17. Knee rest joint; 18. Rotating shaft connecting groove; 19. Locking groove; 20. Rotating shaft connecting pin; 21. Locking piece; 22. Mounting portion; 23. Mounting hole; 24. Presser foot crank rod; 25. Abutment end one; 26. Abutment end two; 27. Presser foot return spring; 28. Oil box; 29. ​​First output end; 30. Second output end; 31. Electric presser foot lifting mechanism; 32. Needle distance adjustment mechanism. DETAILED DESCRIPTION

[0031] The specific implementation of the technical solution is further described in detail below with reference to the accompanying drawings.

[0032] like Figure 1 As shown, the knee-rest presser foot lifting mechanism is a component of the sewing machine, which is arranged in the sewing machine, and includes a base 1, a presser foot assembly 2, a motor drive assembly 5 and a knee-rest drive assembly 6. The presser foot assembly 2 is controlled by the motor drive assembly 5 and the knee-rest drive assembly 6. When the sewing machine needs to trim the thread when working normally, the motor drive assembly 5 electronically controls the presser foot assembly 2 to trim the thread first, and then lifts the presser foot after the thread trimming operation. When rotation or other operations are required, the presser foot assembly 2 can be controlled by manually driving the knee-rest drive assembly 6.

[0033] Specifically, the presser foot assembly 2 has at least a presser foot transmission crank 3 and a presser foot part 4. The presser foot transmission crank 3 is the starting section for the presser foot assembly 2 to receive power, and the presser foot part 4 is the terminal of the presser foot assembly 2. A series of transmission structures are arranged between the presser foot transmission crank 3 and the presser foot part 4. The presser foot transmission crank 3 is rotatably arranged on the base 1. When the presser foot transmission crank 3 rotates, the presser foot part 4 can be raised and lowered.

[0034] like Figure 2-4As shown in the figure, the presser foot drive crank 3 is in a "C" shape, with its two sides being the first abutting end 25 and the second abutting end 26 respectively. The presser foot crank rod 24 passes through both the first abutting end 25 and the second abutting end 26 and is inserted into the base 1. Therefore, pushing either the first abutting end 25 or the second abutting end 26 can make it swing, and the lifting and lowering of the presser foot part 4 are controlled by the swing of the presser foot drive crank 3. Moreover, the knee rest drive assembly 6 abuts against the first abutting end 25 movably, and the output end of the motor drive assembly 5 abuts against the second abutting end 26 movably. Therefore, both the knee rest drive assembly 6 and the motor drive assembly 5 can control the lifting and lowering of the presser foot part 4.

[0035] Furthermore, the part of the presser foot crank rod 24 inserted into the base 1 is located between the first abutting end 25 and the second abutting end 26. A presser foot return spring 27 is sleeved on the presser foot crank rod 24. The two ends of the presser foot return spring 27 are fixed on the base 1 and the second abutting end 26 respectively. The presser foot return spring 27 is arranged between the base 1 and the second abutting end 26. Such an arrangement can limit the presser foot return spring 27 through the base 1 and the second abutting end 26 to ensure the stability of its operation. At the same time, fixing parts are arranged at both ends of the presser foot crank rod 24, and the fixing parts are used to fix the presser foot drive crank 3 on the presser foot crank rod 24.

[0036] As Figure 3-6 shown in the figure, the knee rest drive assembly 6 realizes the lifting and lowering of the presser foot part 4 through a series of transmissions by receiving external power (i.e., the thrust of the human leg). Therefore, the knee rest drive assembly 6 must have the properties of fast and stable transmission. The knee rest drive assembly 6 includes a power input part 7, a power transmission part 10, and a power output part 13. The power input part 7 includes a knee rest plate 8 and a knee rest connecting shaft 9. The knee rest plate 8 has a large surface area, which can better adapt to the human leg. The knee rest connecting shaft 9 is inserted into the knee rest plate 8 and is in an "L" shape. The knee rest connecting shaft 9 can transmit power and save effort. The power transmission part 10 includes a knee rest shaft pin 11 and a knee rest rotating shaft 12. The knee rest rotating shaft 12 is connected to the knee rest connecting shaft 9 through the knee rest shaft pin 11. The knee rest rotating shaft 12 and the knee rest shaft pin 11 are connected to form a straight line. Its detachable installation method can make it easier to be assembled. The knee rest rotating shaft 12 is rotatably arranged on the base 1. The power output part 13 includes a knee rest crank 14 and a knee rest ball 15. The knee rest crank 14 is arranged at the front end of the knee rest rotating shaft 12. The knee rest ball 15 is arranged at the front end of the knee rest crank 14 and is close to the first abutting end 25. The knee rest ball 15 has a spherical surface. When the knee rest plate 8 is pushed, the spherical surface of the knee rest ball 15 can be made to approach the first abutting end 25 and always abut against the first abutting end 25.

[0037] Furthermore, a knee rest reset spring 16 is sleeved on the knee rest shaft 12, and its two ends are respectively fixed on the base 1 and the knee rest crank 14, the knee rest reset spring 16 can help the knee rest drive assembly 6 to reset, and a locking member 21 is provided on the knee rest shaft 12, and the locking member 21 movably abuts against the base 1, and the setting of the locking member 21 can ensure that the knee rest drive assembly 6 will not reset excessively; the knee rest axis pin 11 is connected to the knee rest connecting shaft 9 through the knee rest joint 17, and the knee rest axis pin 11 and the knee rest connecting shaft 9 are inserted on different side walls of the knee rest joint 17, and the knee rest joint 17 can both transmit power and change the direction of power. At the same time, it cooperates with the knee rest plate 8 to form a labor-saving lever, which is convenient for people to use.

[0038] like Figure 3-6 As shown, a shaft connecting groove 18 is provided at the front end of the knee rest shaft pin 11, and the shaft connecting groove 18 has a locking groove 19. A shaft connecting pin 20 is inserted on the knee rest shaft 12. When the knee rest shaft 12 is connected to the knee rest shaft pin 11, the shaft connecting pin 20 is clamped in the shaft connecting groove 18. When the knee rest shaft 12 rotates, the shaft connecting pin 20 enters and is clamped in the locking groove 19. The shaft connecting pin 20 can ensure the circumferential fixation of the knee rest shaft pin 11 and the knee rest shaft 12. When the shaft connecting pin 20 is in the locking groove 19, the axial fixation of the knee rest shaft pin 11 and the knee rest shaft 12 can be ensured.

[0039] Furthermore, an oil box 28 is provided under the base 1, and two mounting parts 22 are formed on the oil box 28. Both ends of the knee rest shaft 12 are inserted into the mounting holes 23 opened on the mounting parts 22, so that the knee rest shaft 12 can rotate in the mounting hole 23, and the knee rest crank 14 and the knee rest return spring 16 are both located between the two mounting parts 22. The two mounting parts 22 can clamp and limit the knee rest return spring 16. One end of the knee rest return spring 16 is inserted into the mounting part 22 on the side close to the knee rest shaft pin 11, and the other end abuts against the knee rest crank 14.

[0040] like Figure 1 and Figure 7 As shown, a sewing machine includes a knee-supported presser foot lifting mechanism, a thread trimming mechanism, an electric-controlled presser foot lifting mechanism 31 and a stitch length adjusting mechanism 32; a motor drive assembly 5 has a first output terminal 29 and a second output terminal 30, the first output terminal 29 drives the electric-controlled presser foot lifting mechanism 31 and the stitch length adjusting mechanism 32, and the second output terminal 30 drives the thread trimming mechanism, the principle of which has been described in detail in Chinese patent CN116446116A, and will not be elaborated on here. In particular, in the present application, the knee-supported presser foot lifting mechanism and the electric-controlled presser foot lifting mechanism 31 share a presser foot transmission crank 3.

[0041] It should be noted that the structures, proportions, sizes, etc. drawn in the drawings of this specification are only used to match the contents disclosed in the specification for people familiar with this technology to understand and read, and are not used to limit the limiting conditions for the implementation of the utility model, so they have no substantial technical significance. Any modification of the structure, change of the proportional relationship or adjustment of the size, without affecting the effects and purposes that can be achieved by the utility model, should still fall within the scope of the technical content disclosed by the utility model. At the same time, the terms such as "upper", "lower", "left", "right", "middle" and "one" quoted in this specification are only for the convenience of description, and are not used to limit the scope of the implementation of the utility model. The change or adjustment of their relative relationship should also be regarded as the scope of the implementation of the utility model without substantial change of the technical content.

[0042] It should also be noted that when an element is referred to as being "fixed on" or "disposed on" another element, it may be directly on the other element or there may be an intermediate element at the same time. When an element is referred to as being "connected to" another element, it may be directly connected to the other element or may be indirectly connected to the other element through an intermediate element.

[0043] In addition, the descriptions of "first", "second", etc. in this application are only for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in this field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by this application.

[0044] The above shows and describes the basic principle and main features of the technical solution and the advantages of the technical solution. The technicians in this industry should understand that the technical solution is not limited by the above embodiments. The above embodiments and the description are only to illustrate the principle of the technical solution. Without departing from the spirit and scope of the technical solution, the technical solution will have various changes and improvements, which fall within the scope of the technical solution to be protected. The scope of protection claimed by the technical solution is defined by the attached claims and their equivalents.

Claims

1. A knee-rest presser foot lifting mechanism, comprising: Base (1); A presser foot assembly (2), comprising a presser foot transmission crank (3) and a presser foot portion (4), wherein the presser foot transmission crank (3) is rotatably disposed on the base (1); and The motor drive assembly (5), whose output end movably abuts against the front end of the presser foot transmission crank (3), is characterized in that it also includes: A knee rest driving assembly (6), the output end of which movably abuts against the rear end of the presser foot driving crank (3); The output ends of the motor drive assembly (5) and the knee rest drive assembly (6) are respectively used to drive the presser foot drive crank (3) to rotate, and the presser foot drive crank (3) realizes the lifting and lowering of the presser foot part (4) by rotating.

2. A knee rest presser foot lifting mechanism according to claim 1, characterized in that: The knee support driving assembly (6) comprises: A power input part (7), comprising a knee rest plate (8) and a knee rest connecting shaft (9) arranged on the knee rest plate (8); A power transmission part (10), comprising a knee rest shaft pin (11) and a knee rest rotating shaft (12) connected to the knee rest shaft pin (11), wherein the knee rest rotating shaft (12) is rotatably disposed on the base (1); A power output part (13), comprising a knee crank (14) and a knee ball (15) arranged on the knee crank (14); and A knee rest return spring (16), which is sleeved on the knee rest rotating shaft (12), and has two ends respectively fixed on the base (1) and the knee rest crank (14); The knee rest connecting shaft (9) is connected to the knee rest shaft pin (11), and the knee rest crank (14) is arranged at the front end of the knee rest rotating shaft (12). By pushing the knee rest plate (8), the knee rest ball (15) can be driven to approach and push the presser foot transmission crank (3) to rotate; the spherical surface of the knee rest ball (15) cooperates with the rear end of the presser foot transmission crank (3).

3. A knee rest presser foot lifting mechanism according to claim 2, characterized in that: The knee rest shaft pin (11) is connected to the knee rest connecting shaft (9) via a knee rest joint (17); The knee rest shaft pin (11) and the knee rest connecting shaft (9) are plugged into different side walls of the knee rest joint (17).

4. A knee rest presser foot lifting mechanism according to claim 3, characterized in that: The front end of the knee rest shaft pin (11) is provided with a shaft connection groove (18), the shaft connection groove (18) has a locking groove (19), and the knee rest shaft (12) is provided with a shaft connection pin (20); When the knee rest rotating shaft (12) is connected to the knee rest shaft pin (11), the rotating shaft connecting pin (20) is clamped in the rotating shaft connecting groove (18); When the knee rest shaft (12) rotates, the shaft connecting pin (20) enters and is locked in the locking groove (19).

5. A knee rest presser foot lifting mechanism according to claim 4, characterized in that: A locking member (21) is provided on the kneerest rotating shaft (12), and the locking member (21) movably abuts against the base (1).

6. A knee rest presser foot lifting mechanism according to claim 5, characterized in that: Two mounting parts (22) are formed on the base (1), and both ends of the knee support shaft (12) are inserted into mounting holes (23) provided on the mounting parts (22); The knee rest crank (14) and the knee rest return spring (16) are both located between the two mounting parts (22); One end of the knee rest return spring (16) is plugged into a mounting portion (22) close to one side of the knee rest shaft pin (11).

7. A knee rest presser foot lifting mechanism according to claim 6, characterized in that: An oil box (28) is provided on the lower side of the base (1), and the two mounting portions (22) are provided on the side wall of the oil box (28); The knee support shaft pin (11) and the knee support rotating shaft (12) are arranged along the cloth feeding direction; The knee rest rotating shaft (12) extends toward the position of the presser foot transmission crank (3), the knee rest crank (14) is fixed on the knee rest rotating shaft (12), and the working plane of the knee rest crank (14) is perpendicular to the axial direction of the knee rest rotating shaft (12); The knee rest ball (15) is arranged at the swing end of the knee rest crank (14) and is located at the lower side of the rear end of the presser foot transmission crank (3).

8. A knee rest presser foot lifting mechanism according to claim 7, characterized in that: The presser foot transmission crank (3) is rotatably arranged on the base (1) via a presser foot crank rod (24); The presser foot transmission crank (3) has a first abutment end (25) at the rear end and a second abutment end (26) at the front end, and the presser foot crank rod (24) is simultaneously plugged into the first abutment end (25) and the second abutment end (26); The knee support ball (15) movably abuts against abutment end 1 (25); The output end of the motor drive assembly (5) movably abuts against the abutment end 2 (26).

9. A knee rest presser foot lifting mechanism according to claim 8, characterized in that: The presser foot crank rod (24) is provided with a presser foot return spring (27); The two ends of the presser foot return spring (27) are respectively fixed on the oil box (28) and the second abutment end (26).

10. A sewing machine, characterized in that: It comprises the knee-rest presser foot lifting mechanism as claimed in any one of claims 1 to 9; it also comprises a thread trimming mechanism, an electric-controlled presser foot lifting mechanism (31) and a stitch length adjusting mechanism (32); The motor drive assembly (5) has a first output end (29) and a second output end (30), the first output end (29) drives the electric-controlled presser foot lifting mechanism (31) and the needle distance adjusting mechanism (32), and the second output end (30) drives the thread trimming mechanism; The knee-rest presser foot lifting mechanism and the electric-controlled presser foot lifting mechanism (31) share the presser foot transmission crank (3).

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