A sewing machine rear trailing wheel lifting and placing structure

Abstract

The utility model belongs to sewing machine technical field, especially point to a sewing machine rear tow wheel lift and put structure, driving piece has rotary output part, cam transmission subassembly includes tow wheel lift and put cam, lift and press the block, lift and press the block includes installation main part, one end installation in tow cloth wheel pressure lever shaft, other end is suspended and sets up and has the extension down stretch, follower rotation setting in the lower end of extension, tow wheel lift and put cam has the profile surface, and tow wheel lift and put cam sets up on the rotary output part of driving piece, one end of lift and press the block is connected with tow cloth wheel pressure lever shaft, other end is the suspended end and is provided with follower, follower and the profile surface contact fit, be used for driving the up and down movement of tow cloth wheel pressure lever shaft to realize the lift and put of rear tow wheel, the utility model discloses through lift and put cam directly drive lift and press the block action, further reach the purpose of lift and put rear tow wheel, transmission path is short, and the structure is simplified, and assembly is simple, convenient.

Description

Technical Field

[0001] This utility model belongs to the field of sewing machine technology, and specifically refers to a rear wheel lifting structure for a sewing machine. Background Technology

[0002] The rear roller on a sewing machine assists in feeding materials, thus requiring lifting and lowering during sewing operations. Chinese Utility Model Patent (Authorization Announcement No. CN 218561800U, Announcement Date 2023.03.03) discloses a rear roller lifting and lowering device and a sewing machine. This device includes a drive motor, a lifting rod, and a cam transmission mechanism. One end of the lifting rod is connected to a lifting stop block of the rear roller device; one end of the cam transmission mechanism is connected to a rotating shaft, and the other end is connected to the other end of the lifting rod. This utility model uses a drive motor as the driving source to drive the lifting rod's raising and lowering, ultimately achieving the lifting and lowering of the rear roller. This rear roller lifting and lowering device has a complex mechanical structure, a long transmission chain, and high requirements for the drive motor, requiring significant start-stop torque and power. Summary of the Invention

[0003] The purpose of this invention is to provide a sewing machine rear wheel lifting structure with a short transmission path and reduced requirements on the motor.

[0004] This utility model is implemented as follows: A rear wheel lifting and lowering structure for a sewing machine includes a rear wheel assembly. The rear wheel assembly includes a feed roller pressure rod shaft, a drive component, and a cam transmission assembly. The drive component has a rotary output section. The cam transmission assembly includes a wheel lifting and lowering cam and a lifting and pressing block. The lifting and pressing block includes a mounting body, one end of which is mounted on the feed roller pressure rod shaft, and the other end is suspended and extends downwards. A driven member is rotatably disposed at the lower end of the extension. The wheel lifting and lowering cam has a contour surface and is disposed on the rotary output section of the drive component. One end of the lifting and pressing block is connected to the feed roller pressure rod shaft, and the other end is a suspended end with a driven member. The driven member contacts and engages with the contour surface to drive the feed roller pressure rod shaft to move up and down to achieve the lifting and lowering of the rear wheel.

[0005] In the above-mentioned sewing machine rear wheel lifting structure, the profile surface includes an outer cam surface formed on the outer periphery of the wheel lifting cam or a cam track formed on the side of the wheel lifting cam.

[0006] In the above-mentioned sewing machine rear wheel lifting structure, the driven member is a rolling member, which is a roller or a bearing.

[0007] In the above-mentioned sewing machine rear roller lifting structure, the rear roller assembly further includes a cloth roller pressure rod bearing seat, and a manual lifting crank is rotatably mounted on the cloth roller pressure rod bearing seat. The manual lifting crank includes a rotating shaft part and a crank part. The rotating shaft part is rotatably mounted on the cloth roller pressure rod bearing seat and connected to the presser foot wrench. An abutment pin is provided on the crank part, and the abutment pin is located below the lifting stop block.

[0008] In the above-mentioned sewing machine rear wheel lifting structure, the sewing machine includes a machine housing, a base is provided on the outer side of the machine housing, a rear cover plate is provided on the outer side of the base, the driving component is located below the base, and is mounted on the rear cover plate extending to the bottom of the base via a mounting seat.

[0009] In the above-mentioned sewing machine rear wheel lifting structure, the mounting base is provided with a through hole for the rotating output part to pass through, and the rotating output part is rotatably connected to the through hole through a bearing.

[0010] In the above-mentioned sewing machine rear wheel lifting structure, the driving component is a motor or a rotary cylinder, and the rotary output part is an output shaft.

[0011] In the above-mentioned sewing machine rear wheel lifting structure, a position detection component is also included. The position detection component includes a Hall sensor disposed on the mounting base and a magnet disposed on the wheel lifting cam. The Hall sensor is used to detect the rotational position of the wheel lifting cam.

[0012] In the above-described sewing machine rear wheel lifting and lowering structure, the Hall sensor is electrically connected to the drive component, and the position detection component is used to control the drive component to stop at a predetermined position corresponding to the lifting or lowering of the rear wheel based on the rotational position of the wheel lifting and lowering cam.

[0013] The outstanding advantages of this utility model compared to the prior art are: 1. This utility model directly drives the lifting and pressing block to lift and lower the rear trailer by lifting and lowering the cam. The transmission path is short, the structure is simplified, and the assembly is simple and convenient. At the same time, it also reduces the requirements for the driving components and further reduces the production cost.

[0014] 2. The lifting and pressing block of this utility model constitutes a highly efficient lever structure, which not only increases the driving arm, making the lifting and lowering action of the rear trailer wheel more labor-saving and more responsive, but also directly converts the pushing force of the trailer wheel lifting and lowering cam into lifting motion, making the force transmission path more direct and efficient.

[0015] 3. This utility model makes full use of the lower space of the base, making the structure more compact. The rear cover plate and the base form a relatively isolated space, which can protect the drive components and effectively prevent the intrusion of dust and wire ends. At the same time, it can also make the whole machine cleaner and more beautiful. Attached Figure Description

[0016] Figure 1 This is a three-dimensional schematic diagram of the present invention mounted on the casing via a base.

[0017] Figure 2 This is a schematic diagram of the present invention installed on the base and in a vertical position.

[0018] Figure 3 This is a schematic diagram of the present invention installed on the base and in an inclined position.

[0019] Figure 4 This is a schematic diagram of the motor of this utility model connected to the lifting cam and the lifting stop block via a roller.

[0020] Figure 5 This is a schematic diagram of the cam for lifting and lowering a tow wheel according to this utility model.

[0021] Figure 6 This is a schematic diagram of the lifting and pressing stop of this utility model.

[0022] In the diagram: 1. Housing; 2. Rear wheel assembly; 3. Drive unit; 4. Mop wheel pressure rod shaft; 5. Rotary output unit; 6. Mop wheel lifting cam; 7. Lifting stop block; 8. Follower; 9. Rear wheel; 10. Outer cam surface; 11. Mounting body; 12. Extension; 13. Mop wheel pressure rod shaft seat; 14. Manual lifting crank; 15. Presser foot wrench; 16. Abutment pin; 17. Base; 18. Rear cover plate; 19. Mounting seat; 20. Pressure adjusting guide rod; 21. Hall sensor; 22. Magnet. Detailed Implementation

[0023] The present invention will be further described below with reference to specific embodiments. See also: Figure 1 —6: This utility model provides a rear drag wheel lifting and lowering structure for a sewing machine. The rear drag wheel lifting and lowering structure is installed on the machine housing 1 and includes a rear drag wheel assembly 2, a driving component 3, and a cam transmission assembly. The rear drag wheel assembly 2 includes a drag wheel pressure rod shaft 4. The driving component 3 has a rotation output part 5. The cam transmission assembly includes a drag wheel lifting and lowering cam 6 and a lifting and pressing block 7. The drag wheel lifting and lowering cam 6 has a contour surface and is disposed on the rotation output part 5 of the driving component 3. One end of the lifting and pressing block 7 is connected to the drag wheel pressure rod shaft 4, and the other end is a suspended end and is provided with a follower 8. The follower 8 contacts and cooperates with the contour surface to drive the drag wheel pressure rod shaft 4 to move up and down to realize the lifting and lowering of the rear drag wheel 9.

[0024] Furthermore, the lifting and pressing block 7 includes a mounting body 11, one end of which is mounted on the mop wheel pressure rod shaft 4, and the other end is suspended and extends downward with an extension 12. The driven member 8 is located at the lower end of the extension 12. The structure of the lifting and pressing block 7 of this utility model constitutes a highly efficient lever structure, which not only increases the driving arm, making the lifting and lowering action of the rear mop wheel more effortless and more responsive, but also directly converts the pushing force of the mop wheel lifting and lowering cam 6 into lifting motion, making the force transmission path more direct and efficient.

[0025] This utility model directly drives the lifting and pressing block 7 to lift and release the rear trailer by lifting and releasing the lifting cam 6. The transmission path is short, the structure is simplified, and the assembly is simple and convenient. At the same time, it also reduces the requirements for the driving component 3 and further reduces the production cost.

[0026] Furthermore, the profile surface includes an outer cam surface 10 formed on the outer periphery of the tow wheel lifting cam 6 or a cam track formed on the side of the tow wheel lifting cam 6. In this embodiment, the structure of the outer cam surface 10 is preferred.

[0027] Furthermore, the driven member 8 of this invention is a rolling element, which can be a roller or a bearing. In this embodiment, a bearing is preferred, and the bearing is mounted on the lifting stop 7 by a shaft screw, resulting in smoother transmission. Of course, the driven member can also be a non-rolling element.

[0028] This utility model also features a structure for manually raising and lowering the rear trailer wheel. Specifically, the rear trailer wheel assembly 2 further includes a mop wheel pressure rod axle seat 13. A manual lifting crank 14 is rotatably mounted on the mop wheel pressure rod axle seat 13. The manual lifting crank 14 includes a pivot portion and a crank portion. The pivot portion is rotatably mounted on the mop wheel pressure rod axle seat 13 and connected to a pressure foot wrench 15. A stop pin 16 is provided on the crank portion, and the stop pin 16 is located below the lifting stop block 7. When manual lifting is required, simply rotate the pressure foot wrench 15, which drives the stop pin 16 to act on the lifting stop block 7 and move it upward through the manual lifting crank 14; conversely, the rear trailer wheel 9 is lowered. In this utility model, a pressure spring is fitted on the pressure adjusting guide rod 20 between the lifting stop block 7 and the mop wheel pressure rod axle seat 13 to drive the lifting stop block 7 to move downward.

[0029] In this invention, a base 17 is also provided on the outer side of the housing 1, and a rear cover plate 18 is provided on the outer side of the base 17. The drive component 3 is located below the base 17 and is mounted on the rear cover plate 18 extending below the base 17 via a mounting base 19. As can be seen from the above, this invention makes full use of the lower space of the base 17, resulting in a more compact structure. The rear cover plate 18 and the base 17 form a relatively isolated space, which can protect the drive component 3 and effectively prevent the intrusion of dust and wire ends, while also making the whole machine cleaner and more aesthetically pleasing.

[0030] Furthermore, the present invention provides a through hole on the mounting base 19 for the rotary output part 5 to pass through, and the rotary output part 5 is rotatably connected to the through hole via a bearing. The fit between the through hole and the bearing provides rotational support for the rotary output part 5, ensuring the smooth operation of the rotary output part 5 and the lifting cam of the towing wheel.

[0031] It should be noted that the driving component 3 is a motor or a rotary cylinder, and the rotary output part 5 is an output shaft. In this embodiment, the driving component 3 is preferably a motor.

[0032] This invention also includes a position detection component, which comprises a Hall sensor 21 disposed on the mounting base 19 and a magnet 22 disposed on the tow wheel lifting cam 6. The Hall sensor 21 is used to detect the rotational position of the tow wheel lifting cam 6. Specifically, the Hall sensor 21 is electrically connected to the drive member 3, and the position detection component is used to control the drive member 3 to stop at a predetermined position corresponding to the lifting or lowering of the rear tow wheel 9 based on the rotational position of the tow wheel lifting cam 6.

[0033] When the drive unit 3 rotates the trailer wheel lifting cam 6, the magnet 22 on the cam rotates to a specific angle and gradually approaches the Hall sensor 21. The Hall sensor 21 is triggered by the magnetic field of the magnet 22, and its output voltage signal changes significantly. The voltage signal of the Hall sensor 21 is transmitted in real time to the controller of this trailer wheel lifting structure. The controller has a preset threshold voltage. The controller compares the received changed voltage signal with the preset threshold voltage. When the signal reaches the threshold, it means that the trailer wheel lifting cam 6 has rotated to the target position that allows the trailer wheel 9 to complete the lifting or lowering action. The controller then sends a stop command to the drive unit 3. Correspondingly, the trailer wheel lifting cam 6 also stops at the current position. Through the linkage of the lifting stop block 7, the trailer wheel 9 remains in the current lifted or lowered state.

[0034] In addition, the drive unit 3 can also use the program in the controller to control its rotation angle, thereby limiting the position of the towing wheel lifting cam 6 and ensuring the lifting or lowering of the rear towing wheel 9.

[0035] The above embodiments are only one of the preferred embodiments of this utility model and are not intended to limit the scope of implementation of this utility model. Therefore, all equivalent changes made in accordance with the shape, structure and principle of this utility model should be covered within the protection scope of this utility model.

Claims

1. A rear drag wheel lifting structure for a sewing machine, comprising a rear drag wheel assembly (2), wherein the rear drag wheel assembly (2) includes a drag wheel pressure rod shaft (4), characterized in that: It also includes a drive unit (3) and a cam transmission assembly. The drive unit (3) has a rotation output part (5). The cam transmission assembly includes a wheel lifting cam (6) and a lifting stop block (7). The lifting stop block (7) includes a mounting body (11). One end of the mounting body (11) is mounted on the mop wheel pressure rod shaft (4), and the other end is suspended and extends downward with an extension part (12). A follower (8) is rotatably disposed at the lower end of the extension part. The wheel lifting cam (6) has a contour surface and is disposed on the rotation output part (5) of the drive unit (3). One end of the lifting stop block (7) is connected to the mop wheel pressure rod shaft (4), and the other end is a suspended end with a follower (8). The follower (8) contacts and cooperates with the contour surface to drive the mop wheel pressure rod shaft (4) to move up and down to realize the lifting and lowering of the rear wheel (9).

2. The sewing machine rear wheel lifting structure according to claim 1, characterized in that: The profile surface includes an outer cam surface (10) formed on the outer periphery of the trolley lifting cam (6) or a cam track formed on the side of the trolley lifting cam (6).

3. A sewing machine rear wheel lifting structure according to claim 1 or 2, characterized in that: The driven member (8) is a rolling element, which is a roller or a bearing.

4. A sewing machine rear wheel lifting structure according to claim 1 or 2, characterized in that: The rear tow wheel assembly (2) also includes a tow wheel pressure rod seat (13), on which a manual lifting crank (14) is rotatably mounted. The manual lifting crank (14) includes a shaft part and a crank part. The shaft part is rotatably mounted on the tow wheel pressure rod seat (13) and connected to the press foot wrench (15). The crank part is provided with an abutment pin (16), which is located below the lifting stop block (7).

5. The sewing machine rear wheel lifting structure according to claim 1, characterized in that: The sewing machine includes a housing (1), a base (17) is provided on the outer side of the housing (1), a rear cover plate (18) is provided on the outer side of the base (17), and the drive member (3) is located below the base (17) and is mounted on the rear cover plate (18) extending below the base (17) via a mounting seat (19).

6. The sewing machine rear wheel lifting structure according to claim 5, characterized in that: The mounting base (19) is provided with a through hole for the rotary output part (5) to pass through, and the rotary output part (5) is rotatably connected to the through hole by a bearing.

7. A sewing machine rear wheel lifting structure according to claim 1, 5, or 6, characterized in that: The driving component (3) is a motor or a rotary cylinder, and the rotary output part (5) is an output shaft.

8. A sewing machine rear wheel lifting structure according to claim 5 or 6, characterized in that: It also includes a position detection component, which includes a Hall sensor (21) disposed on the mounting base (19) and a magnet (22) disposed on the trolley lifting cam (6). The Hall sensor (21) is used to detect the rotational position of the trolley lifting cam (6).

9. The sewing machine rear wheel lifting structure according to claim 8, characterized in that: The Hall sensor (21) is electrically connected to the drive unit (3), and the position detection component is used to control the drive unit (3) to stop at a predetermined position corresponding to the lifting or lowering of the rear trailer wheel (9) according to the rotational position of the trailer wheel lifting cam (6).

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