Internal and external presser foot pressing mechanism

Abstract

The utility model belongs to the technical field of sewing machines, and particularly relates to an inner and outer presser foot pressing mechanism which comprises an inner presser foot and an outer presser foot which are connected with a transmission assembly. A first elastic piece is arranged at the upper end of the pressing rod sleeve, and the lower end of the pressing rod sleeve acts on the inner pressing foot and is used for providing pressing force for the inner pressing foot through the first elastic piece; the lifting rod is arranged in the pressing rod sleeve in a sliding mode, a second elastic piece is arranged at the upper end of the lifting rod, and the lower end of the lifting rod acts on the outer pressing foot; according to the pressing device, when the lifting rod is driven to slide upwards, the first spring still normally acts on the pressing rod sleeve to provide pressing force for the pressing foot fixing frame, and then pressing force is provided for the inner pressing foot, so that the inner pressing foot still has good pressing force when the inner pressing foot and the outer pressing foot operate alternately, and therefore the pressing force of the inner pressing foot is improved. Therefore, the cloth can be better pressed, and the phenomenon that the cloth deviates is prevented.

Description

Technical Field

[0001] This utility model belongs to the field of sewing machine technology, and specifically refers to an inner and outer presser foot clamping mechanism. Background Technology

[0002] Chinese utility model 201922502144 discloses a feeding device and a sewing machine having the same, comprising: inner and outer presser foot assemblies for pressing and conveying materials; a transmission assembly connected to the inner and outer presser foot assemblies to transmit power to the inner and outer presser foot assemblies, the transmission assembly including a swing shaft; and a feeding motor having an output shaft.

[0003] This patent has the following drawbacks:

[0004] In this sewing machine, the inner and outer presser feet share a single pressing rod for clamping. The pressing rod includes two opposing presser sleeves and a lifting rod located between the two presser sleeves. One end of the lifting rod is fitted with a compression spring. Since the inner and outer presser feet operate differentially, when the outer presser foot is lifted, the lifting rod moves upward via the lifting crank, compressing the compression spring. This affects the clamping force on the inner presser foot, resulting in the inner presser foot being unable to clamp the fabric when the sewing machine is moving rapidly, causing the fabric to shift left and right. Summary of the Invention

[0005] The purpose of this invention is to provide an inner and outer pressure foot clamping mechanism that effectively guarantees the pressure of the inner pressure foot.

[0006] The purpose of this utility model is achieved as follows:

[0007] The inner and outer pressure foot clamping mechanism includes:

[0008] The inner and outer pressure feet are connected by a transmission assembly, which is used to press the inner and outer pressure feet together and convey materials.

[0009] The pressure bar sleeve has a first elastic element at its upper end and the lower end of the pressure bar sleeve acts on the inner pressure foot to provide a clamping force to the inner pressure foot through the first elastic element.

[0010] The lifting rod is slidably disposed within the pressure rod sleeve. The upper end of the lifting rod is provided with a second elastic element, and the lower end of the lifting rod acts on the outer pressure foot.

[0011] Furthermore, the transmission assembly includes:

[0012] A presser foot fixing bracket is connected to the lower end of the presser rod sleeve, and the inner presser foot is connected through the presser foot fixing bracket;

[0013] The presser foot drive frame is equipped with a linkage crank that is movably connected to one end of the lifting rod, and the outer presser foot is connected through the presser foot drive frame; the presser foot drive frame is also connected to a first drive group that drives it to swing, and the first drive group cooperates with the lifting rod to drive the outer presser foot to convey materials.

[0014] Furthermore, the first drive group includes a transmission swing shaft, which is connected to a transmission crank. The transmission crank is connected to a transmission swing pin. One end of the transmission swing pin is provided with a swing sleeve. A swing shaft is slidably provided inside the swing sleeve. The pressure foot drive frame is connected through the swing shaft.

[0015] Furthermore, the transmission assembly also includes a second drive group for driving the lifting rod to slide within the pressure rod sleeve. The drive group includes a lifting shaft, a lifting cam connected to the lifting shaft, a lifting crank connected to the lifting cam, a lifting connecting rod connected to the lifting crank, and a drive crank connected to the other end of the lifting connecting rod. The pressure rod sleeve is provided with a swing plate, and one end of the drive crank abuts against one end of the swing plate.

[0016] The lifting rod is provided with a lifting pin, and the pressure rod sleeve is provided with a lifting groove for the lifting pin to extend outward; the lifting pin is located on the other end of the swing plate, and the lifting pin is moved in the lifting groove by swinging the drive crank to rotate the swing plate.

[0017] Furthermore, the first elastic element includes a first spring, one end of which is provided with a first adjusting seat movably disposed in the frame, and the tension of the first spring is changed by adjusting the position of the first adjusting seat.

[0018] Furthermore, the second elastic element includes a second spring located inside the first spring, and the other end of the second spring is provided with a second adjusting seat movably disposed in the frame, so that the tension of the second spring can be changed by adjusting the position of the second adjusting seat.

[0019] Furthermore, the first spring is fitted onto the upper end of the pressure rod sleeve, and a fixing structure is provided between the second spring and the upper end of the pressure rod sleeve.

[0020] The outstanding and beneficial technical effects of this utility model compared to the prior art are:

[0021] In this patent, when the lifting rod is driven to slide upward, the first spring still acts normally on the pressure rod sleeve to provide pressure foot force to the pressure foot fixing frame, and then to provide clamping force to the inner pressure foot. This ensures that when the inner and outer pressure feet are running alternately, the inner pressure foot still has good clamping force, so as to better clamp the fabric and prevent the fabric from shifting.

[0022] In this patent, both the first elastic element and the second elastic element are independently provided with a first adjustment seat and a second adjustment seat to adjust their pressure. Using these, the pressure can be adjusted according to one's own needs so that the sewing machine can work better. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the front structure of the inner and outer pressure foot clamping mechanism.

[0024] Figure 2 This is a schematic diagram of the rear structure of the inner and outer pressure foot clamping mechanism.

[0025] Figure 3 This is a cross-sectional diagram of the compression sleeve and lifting rod.

[0026] Figure 4 This is a schematic diagram of the split of the second drive group.

[0027] The meaning of the labels in the diagram:

[0028] 1. Inner pressure foot;

[0029] 2. External pressure foot;

[0030] 31. Presser foot drive frame; 32. First drive group; 321. Transmission swing shaft; 322. Transmission crank; 323. Transmission swing pin; 324. Swing sleeve; 325. Swing shaft;

[0031] 33. Presser foot fixing bracket; 34. Linkage crank; 35. Second drive group; 351. Lifting shaft; 352. Lifting cam; 353. Lifting crank; 354. Lifting connecting rod; 355. Drive crank; 3551. Roller assembly; 356. Swing plate; 357. Swing mounting base;

[0032] 4. Pressure rod sleeve; 41. Lifting slide; 42. First elastic element; 43. First adjusting seat;

[0033] 5. Lifting rod; 51. Lifting pin; 52. Second elastic element; 53. Second adjusting seat; 54. Lifting roller; Detailed Implementation

[0034] The present invention will be further described below with reference to specific embodiments:

[0035] The inner and outer pressure foot clamping mechanism includes an inner pressure foot 1 and an outer pressure foot 2, which are connected by a transmission assembly. The transmission assembly is used to clamp the inner pressure foot 1 and the outer pressure foot 2 and convey materials. The mechanism also includes a pressure rod sleeve 4 and a lifting rod 5. The upper end of the pressure rod sleeve 4 is provided with a first elastic element 42, and the lower end of the pressure rod sleeve 4 acts on the inner pressure foot 1 to provide clamping force to the inner pressure foot 1 through the first elastic element 42. The lifting rod 5 is slidably disposed in the pressure rod sleeve 4, and the upper end of the lifting rod 5 is provided with a second elastic element 52. The lower end of the lifting rod 5 acts on the outer pressure foot 2.

[0036] like Figure 1 , 2 As shown, the transmission assembly in this patent includes a presser foot fixing frame 33 and a presser foot drive frame 31. The presser foot fixing frame 33 is generally U-shaped and is fixed to the lower end of the presser rod sleeve 4, with its opening facing rearward and the inner presser foot 1 fixed to its front end. The presser foot drive frame 31 is located below the presser foot fixing frame 33 and is equipped with a linkage crank 34. A lifting roller 54 is provided at the lower end of the lifting rod 5, and the lifting rod 5 passes through the presser rod sleeve 4 and is located in the linkage crank 34. The presser foot drive frame 31 is also connected to a first drive group 32 that drives its swing. The first drive group 32 works with the lifting rod 5 to drive the outer presser foot 2 to convey materials.

[0037] Specifically, such as Figure 2 As shown, the first drive group 32 includes a transmission swing shaft 321. The transmission swing shaft 321 is driven to swing by a motor fixed in the sewing machine housing. The transmission swing shaft 321 is connected to a transmission crank 322, and the transmission crank 322 is connected to a transmission swing pin 323. One end of the transmission swing pin 323 is provided with a swing sleeve 324. The swing sleeve 324 passes through the open end of the presser foot fixing frame 33, and a swing shaft 325 is slidably provided in the swing sleeve 324. The lower end of the swing shaft 325 is hinged to the rear side of the presser foot drive frame 31. By driving the transmission swing shaft 321 to swing, the transmission crank 322, the transmission swing pin 323, and the swing shaft 325 are driven to move in sequence, so that the presser foot drive frame 31 moves back and forth as a whole, thereby driving the outer presser foot 2 fixed at the front end of the presser foot drive frame 31 to move back and forth.

[0038] The transmission assembly also includes a second drive group 35 for driving the lifting rod 5 to slide within the pressure rod sleeve 4. Figure 1 , 4As shown, the second drive group 35 includes a lifting shaft 351, which is also driven by a motor fixed inside the sewing machine housing. The lifting shaft 351 is connected to a lifting cam 352, and a downwardly positioned lifting crank 353 is connected to the lifting cam 352. The lifting crank 353 is connected to a horizontally positioned lifting connecting rod 354, and the other end of the lifting connecting rod 354 is connected to a drive crank 355. A roller 3551 for abutting is provided at the end of the drive crank 355. The pressure rod sleeve 4 is provided with a swing plate 356, and one end of the drive crank 355 abuts against one end of the swing plate 356. In fact, a swing mounting seat 357 is fixed on the pressure rod sleeve 4, and the swing plate 356 is L-shaped and connected to the swing mounting seat 357, with the swing plate 356 positioned on one side of the pressure rod sleeve 4. The lifting rod 5 is provided with a lifting pin 51, and the pressure rod sleeve 4 is provided with a lifting groove 41 for the lifting pin 51 to extend outward. The lifting pin 51 extends toward both sides of the lifting rod 5 and extends outward from the strip-shaped lifting groove 41. The end of the lifting pin 51 is located on the lower end of the swing plate 356. The roller 3551 of the drive crank 355 abuts against the upper end of the swing plate 356. The motor in the sewing machine housing drives the lifting shaft 351 to rotate, thereby sequentially driving the lifting cam 352, the lifting crank 353, and the lifting connecting rod 354 to move, thereby driving the drive crank 355 to swing, so that the roller 3551 abuts against the swing plate 356 and drives the lifting pin 51 to lift upward, so that the lifting rod 5 slides upward in the pressure rod sleeve 4.

[0039] like Figure 3 As shown, since the lifting rod 5 has a lifting roller 54 located in the linkage crank 34, when the lifting rod 5 is lifted upward, it will drive the entire presser foot drive frame 31 to swing upward through the lifting roller 54, thereby driving the outer presser foot 2 on the presser foot drive frame 31 to move up and down, so as to cooperate with the first drive group 32 to make the outer presser foot 2 move in an elliptical trajectory for material conveying.

[0040] The second elastic element 52 is a second spring. The lower end of the second spring is located inside the pressure rod sleeve 4 and abuts against the upper end of the lifting rod 5. A second adjusting seat 53 is provided at the upper end of the second spring. The second adjusting seat 53 is slidably disposed in the frame of the sewing machine. Specifically, it is a screw sliding element. The tension of the second spring can be changed by adjusting the position of the second adjusting seat 53.

[0041] The first elastic element 42 includes a first spring. The lower end of the first spring is connected to the upper end of the pressure rod sleeve 4, and the upper end of the spring is connected to a first adjusting seat 43 that is movably disposed in the sewing machine frame. The first adjusting seat 43 can also be a screw sliding element, and the tension of the first spring can be changed by adjusting the position of the first adjusting seat 43.

[0042] In practice, the first spring is fitted outside the second spring to ensure that they operate independently without interference. The first spring is fitted onto the upper end of the pressure rod sleeve 4, and a fixing structure is provided between the second spring and the upper end of the pressure rod sleeve 4. The fixing structure can be welded or positioned by a shaft hole, which facilitates a better connection between the second spring and the pressure rod sleeve 4. When the lifting rod 5 is driven to slide upward, the first spring still acts normally on the pressure rod sleeve 4 to provide pressure foot force to the pressure foot fixing bracket 33, and thus provide clamping force to the inner pressure foot 1. This ensures that when the inner pressure foot 1 and the outer pressure foot 2 operate alternately, the inner pressure foot 1 still has good clamping force, thereby better pressing the fabric and preventing fabric shifting. The first spring can also act directly on the swing mounting base 357. The first spring applies pressure to the pressure rod sleeve 4 by acting downward on the swing mounting base 357.

[0043] In addition, in this patent, the first elastic element 42 and the second elastic element 52 are each independently provided with a first adjustment seat 43 and a second adjustment seat 53 to adjust their pressure. Using this, the pressure can be adjusted according to one's own needs so that the sewing machine can work better.

[0044] The above embodiments are merely preferred embodiments of the present utility model and are not intended to limit the scope of protection of the present utility model. Therefore, all equivalent changes made to the structure, shape, and principle of the present utility model should be covered within the scope of protection of the present utility model.

[0045] It should be understood that the structures, proportions, sizes, etc., depicted in the accompanying drawings are merely for illustrative purposes to aid those skilled in the art and are not intended to limit the scope of this invention. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in proportions, or adjustments to size, without affecting the effectiveness and purpose of this invention, should still fall within the scope of the disclosed technical content. Furthermore, the terms "upper," "lower," "left," "right," "middle," and "one" used in this specification are merely for clarity and not intended to limit the scope of this invention. Changes or adjustments to their relative relationships, without substantially altering the technical content, should also be considered within the scope of this invention.

[0046] It should also be noted that when a component is referred to as being "fixed to" or "set on" another component, it can be directly on the other component or may be connected to an intermediary component. When a component is referred to as being "connected to" another component, it can be directly connected to the other component or indirectly connected to the other component through an intermediary component.

[0047] Furthermore, the use of terms such as "first" and "second" in this application is for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. Additionally, the technical solutions of the various embodiments can be combined with each other, but only on the basis of being achievable by those skilled in the art. When the combination of technical solutions is contradictory or impossible to implement, such a combination of technical solutions should be considered non-existent and not within the scope of protection claimed in this application.

Claims

1. An inner and outer pressure foot clamping mechanism, characterized in that, include: The inner pressure foot (1) and the outer pressure foot (2) are connected by a transmission assembly. The transmission assembly is used to press the inner pressure foot (1) and the outer pressure foot (2) together and convey the material. A pressure rod sleeve (4) is provided at the upper end of the pressure rod sleeve (4) with a first elastic element (42) and the lower end of the pressure rod sleeve (4) acts on the inner pressure foot (1) to provide a clamping force to the inner pressure foot (1) through the first elastic element (42); The lifting rod (5) is slidably disposed inside the pressure rod sleeve (4). The upper end of the lifting rod (5) is provided with a second elastic element (52), and the lower end of the lifting rod (5) acts on the outer pressure foot (2).

2. The inner and outer pressure foot clamping mechanism according to claim 1, characterized in that, The transmission assembly includes: A presser foot fixing bracket (33) is connected to the lower end of the presser rod sleeve (4), and the inner presser foot (1) is connected through the presser foot fixing bracket (33); The presser foot drive frame (31) is provided with a linkage crank (34) that is movably connected to one end of the lifting rod (5), and the outer presser foot (2) is connected through the presser foot drive frame (31); the presser foot drive frame (31) is also connected to a first drive group (32) that drives it to swing, and the first drive group (32) cooperates with the lifting rod (5) to drive the outer presser foot (2) to convey materials.

3. The inner and outer pressure foot clamping mechanism according to claim 2, characterized in that: The first drive group (32) includes a transmission swing shaft (321), which is connected to a transmission crank (322). The transmission crank (322) is connected to a transmission swing pin (323). One end of the transmission swing pin (323) is provided with a swing sleeve (324). A swing shaft (325) is slidably provided inside the swing sleeve (324). The pressure foot drive frame (31) is connected through the swing shaft (325).

4. The inner and outer pressure foot clamping mechanism according to claim 2, characterized in that: The transmission assembly also includes a second drive group (35) for driving the lifting rod (5) to slide within the pressure rod sleeve (4). The drive group includes a lifting shaft (351), which is connected to a lifting cam (352). The lifting cam (352) is connected to a lifting crank (353), which is connected to a lifting connecting rod (354). The other end of the lifting connecting rod (354) is connected to a drive crank (355). The pressure rod sleeve (4) is provided with a swing plate (356), and one end of the drive crank (355) abuts against one end of the swing plate (356). The lifting rod (5) is provided with a lifting pin (51), and the pressure rod sleeve (4) is provided with a lifting groove (41) for the lifting pin (51) to extend outward; the lifting pin (51) is located on the other end of the swing plate (356), and the lifting pin (51) slides in the lifting groove (41) by swinging the drive crank (355) to drive the swing plate (356) to rotate.

5. The inner and outer pressure foot clamping mechanism according to claim 1, characterized in that: The first elastic element (42) includes a first spring, one end of which is provided with a first adjusting seat (43) movably disposed in the frame. The tension of the first spring can be changed by adjusting the position of the first adjusting seat (43).

6. The inner and outer pressure foot clamping mechanism according to claim 5, characterized in that: The second elastic element (52) includes a second spring located inside the first spring. The other end of the second spring is provided with a second adjustment seat (53) movably disposed in the frame. The tension of the second spring can be changed by adjusting the position of the second adjustment seat (53).

7. The inner and outer pressure foot clamping mechanism according to claim 6, characterized in that: The first spring is fitted onto the upper end of the pressure rod sleeve (4), and a fixing structure is provided between the second spring and the upper end of the pressure rod sleeve (4).

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