Needle bar cloth pricking structure and sewing machine
By employing a reverse rotation design of the main shaft and balance shaft in the sewing equipment, and using staggered and symmetrical balance blocks to counteract the dynamic imbalance of the needle bar assembly, the noise and vibration problems of the sewing equipment are solved, and more stable movement is achieved.
Patent Information
- Application Number
- CN202511995500.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-26
- Publication Date
- 2026-02-10
AI Technical Summary
The needle bar crank design of existing sewing equipment has a dynamic imbalance problem, which leads to increased operating noise and aggravated vibration in the front and back directions.
A first balance block is fixed on the main shaft, and the needle bar crank slider assembly is set 180° with the main shaft. The balance shaft is driven to rotate in the opposite direction through the transmission assembly. Combined with the misaligned and symmetrical second balance block, the movement direction of the needle bar assembly is canceled out in the opposite direction, reducing noise and inertial force.
It effectively reduces the operating noise of sewing equipment, balances the inertial forces in the front and back directions of the needle bar piercing structure, reduces vibration in the front and back directions, and improves the overall stability of the movement.
Smart Images
Figure CN121496673A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of sewing equipment technology, and more particularly to a needle bar needle-punching structure and a sewing machine. Background Technology
[0002] For sewing equipment such as flatbed sewing machines and coverstitch sewing machines, their needle bar structure typically includes a needle bar assembly and a needle bar crank-slider assembly whose output end is connected to the needle bar assembly. The input end of the needle bar crank-slider assembly is connected to the sewing machine spindle to convert the high-speed rotational motion of the sewing machine spindle into the vertical up-and-down motion of the needle bar, thereby realizing the up-and-down motion of the needle.
[0003] Most current flatbed sewing machines employ a needle bar crank reverse balance design in their needle bar structure, the core purpose of which is to counteract the dynamic imbalance caused by the up-and-down movement of the needle bar. However, this design has two major drawbacks: First, due to the limited internal space of the equipment, if the counterweight at the needle bar crank is added to enhance the balance effect, it will directly compress the movement space of the lower needle bar connector slider relative to the guide rail. This causes the needle bar connector slider to easily slip off the guide rail during the up-and-down reciprocating motion. Tests have verified that this slippage problem significantly increases the machine's operating noise. Second, the needle bar crank itself performs circular motion, and this motion characteristic will further aggravate the inertial force in the front-and-back direction of the entire equipment, leading to increased vibration in the front-and-back direction of the sewing machine.
[0004] Therefore, a needle bar piercing structure and a sewing machine are needed to solve the above problems. Summary of the Invention
[0005] The purpose of this invention is to provide a needle bar piercing structure and a sewing machine that can reduce operating noise and balance the inertial forces in the front and rear directions of the needle bar piercing structure, thereby reducing vibration in the front and rear directions.
[0006] To achieve this objective, the present invention adopts the following technical solution:
[0007] The needle bar piercing structure includes:
[0008] A main spindle, on which a first balance block is fixedly mounted;
[0009] A needle bar crank slider assembly, wherein the crank of the needle bar crank slider assembly is connected to one end of the main shaft, and the first balance block is arranged at 180° with the crank about the main shaft;
[0010] A needle bar assembly, wherein the needle bar slider of the needle bar crank slider assembly is connected to the needle bar assembly, and the needle bar slider is rotatably connected to the crank via a needle bar connecting rod;
[0011] A balance shaft is provided, which is parallel to and spaced apart from the main shaft. A second balance block is fixedly provided on the balance shaft, and the second balance block is symmetrically and offset from the first balance block.
[0012] A transmission assembly is disposed between the main shaft and the balance shaft. The main shaft drives the balance shaft to rotate through the transmission assembly, and the balance shaft rotates in the opposite direction to the main shaft.
[0013] In some embodiments, the transmission assembly includes a driving gear and a driven gear, the driving gear being fixedly sleeved on the main shaft, the driven gear being fixedly sleeved on the balance shaft, and the driving gear meshing with the driven gear.
[0014] In some embodiments, the crank includes a thread take-up crank portion and a needle bar crank portion connected to each other, the needle bar crank portion being connected to one end of the main shaft, and the thread take-up crank portion being rotatably connected to the needle bar connecting rod.
[0015] In some embodiments, a slide rail is further included, which is fixedly disposed within the housing, and the needle bar slider is slidably disposed on the slide rail.
[0016] In some embodiments, a first bushing and a second bushing are fitted at both ends of the balance shaft, the balance shaft is rotatable relative to the first bushing and the second bushing, and the first bushing and the second bushing are fixedly connected to the housing.
[0017] In some embodiments, a first spindle sleeve and a second spindle sleeve are spaced apart on the spindle, the spindle is rotatable relative to the first spindle sleeve and the second spindle sleeve, and the first spindle sleeve and the second spindle sleeve are fixedly connected to the housing.
[0018] In some embodiments, the needle bar assembly includes a needle bar body, a first needle bar bushing, and a second needle bar bushing. The needle bar body is arranged vertically, and the first needle bar bushing and the second needle bar bushing are spaced apart and sleeved on the needle bar body. The needle bar body is slidable relative to the first needle bar bushing and the second needle bar bushing. The needle bar body is connected to the needle bar slider, and the first needle bar bushing and the second needle bar bushing are fixedly connected to the housing.
[0019] In some embodiments, a needle bar connector is provided on the needle bar slider, and the needle bar connector is connected to the needle bar body.
[0020] In some embodiments, an organic needle is provided at the lower end of the needle bar body.
[0021] A sewing machine, including the needle bar needle-punching structure described above.
[0022] The beneficial effects of this invention are:
[0023] The present invention provides a needle bar piercing structure, wherein a first balance block is fixedly mounted on a main shaft, and the crank of a needle bar crank-slider assembly is connected to one end of the main shaft, with the first balance block and the crank positioned at 180° about the main shaft. The needle bar slider of the needle bar crank-slider assembly is connected to the needle bar assembly, and the needle bar slider is rotatably connected to the crank via a needle bar connecting rod. A balance shaft is parallel to and spaced apart from the main shaft, and a second balance block is fixedly mounted on the balance shaft, symmetrically arranged with the first balance block. A transmission assembly is provided between the balance shaft and the main shaft, and the main shaft drives the balance shaft to rotate via the transmission assembly. When the main shaft rotates, it drives the balance shaft to rotate in the opposite direction via the transmission assembly, and the crank drives the needle bar assembly to move up and down via the needle bar crank-slider assembly. During this process, since the first balance block and the crank are positioned at 180° about the main shaft, and the second balance block and the first balance block are symmetrically arranged, the needle bar assembly is in a downward movement state as the first and second balance blocks move upward, making the movement directions of the balance block and the needle bar assembly opposite, thereby effectively balancing the dynamic imbalance caused by the movement of the needle bar assembly. Since the first balance block is arranged on the main shaft, it is easy to place and will not encroach on the space of the needle bar slider, thereby reducing operating noise. Because the first and second balance blocks are staggered and symmetrically arranged and rotate in opposite directions, they can balance the inertial forces in the front and back directions of the needle bar needle-punching structure. This allows the imbalance in the movement of the first and second balance blocks to cancel each other out through their opposite movements, reducing vibration in the front and back directions and improving the overall stability of the movement.
[0024] The present invention provides a sewing machine, which includes the needle bar needle-punching structure as described above, which can reduce operating noise and balance the inertial force of the needle bar needle-punching structure in the front and back directions, thereby reducing vibration in the front and back directions. Attached Figure Description
[0025] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments of the present invention will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the content of the embodiments of the present invention and these drawings without creative effort.
[0026] Figure 1 This is a schematic diagram of a needle bar pierced fabric structure according to the present invention;
[0027] Figure 2 This is a front view of a sewing machine according to the present invention;
[0028] Figure 3 This is a simulation data analysis diagram of the original needle bar piercing fabric structure and the current needle bar piercing fabric structure.
[0029] In the picture:
[0030] 100. Machine housing; 1. Main shaft; 11. First balance block; 12. First main shaft sleeve; 13. Second main shaft sleeve; 2. Needle bar crank slider assembly; 21. Needle bar crank part; 22. Thread take-up crank part; 23. Needle bar connecting rod; 24. Needle bar slider; 241. Needle bar connector; 25. Slide rail; 3. Needle bar assembly; 31. Needle bar body; 32. First needle bar bushing; 33. Second needle bar bushing; 34. Needle; 4. Balance shaft; 41. Second balance block; 42. First bushing; 43. Second bushing; 5. Transmission assembly; 51. Drive gear; 52. Driven gear. Detailed Implementation
[0031] Before explaining any implementation of this application in detail, it should be understood that this application is not limited to its application to the structural details and component arrangements set forth in the following description or shown in the above drawings.
[0032] In this application, the terms "comprising," "including," "having," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.
[0033] In this application, the terms "connection," "combination," "coupling," and "installation" can refer to direct connection, combination, coupling, or installation, or indirect connection, combination, coupling, or installation. For example, a direct connection refers to two parts or components being connected together without the need for an intermediary, while an indirect connection refers to two parts or components each being connected to at least one intermediary, with the connection achieved through the intermediary. Furthermore, "connection" and "coupling" are not limited to physical or mechanical connections or couplings, but can also include electrical connections or couplings.
[0034] In this application, those skilled in the art will understand that the function performed by a component can be performed by one component, multiple components, one part, or multiple parts. Similarly, the function performed by a part can also be performed by one part, one component, or a combination of multiple parts.
[0035] In this application, the directional terms "upper," "lower," "left," "right," "front," and "rear" are used to describe the orientation and positional relationships shown in the accompanying drawings and should not be construed as limiting the embodiments of this application. Furthermore, in the context, it should be understood that when an element is mentioned as being connected "upper" or "lower" to another element, it can be directly connected to the other element "upper" or "lower," or indirectly connected through an intermediate element. It should also be understood that directional terms such as upper side, lower side, left side, right side, front side, and rear side not only represent positive orientation but can also be understood as lateral orientation. For example, "below" can include directly below, lower left, lower right, lower front, and lower rear.
[0036] During the operation of sewing equipment such as flatbed sewing machines and coverstitch sewing machines, in order to reduce operating noise and balance the inertial forces in the front-to-back direction of the needle bar needle bar structure, and reduce vibration in the front-to-back direction, such as... Figures 1-2 As shown, the present invention provides a needle bar piercing structure. The needle bar piercing structure includes a main shaft 1, a needle bar crank slider assembly 2, a needle bar assembly 3, a balance shaft 4, and a transmission assembly 5.
[0037] The main shaft 1 is fixedly mounted with a first balance block 11. The crank of the needle bar crank-slider assembly 2 is connected to one end of the main shaft 1, and the first balance block 11 is positioned at 180° to the crank about the main shaft 1. The needle bar slider 24 of the needle bar crank-slider assembly 2 is connected to the needle bar assembly 3, and the needle bar slider 24 is rotatably connected to the crank via a needle bar connecting rod 23. The balance shaft 4 is parallel to and spaced apart from the main shaft 1, and a second balance block 41 is fixedly mounted on the balance shaft 4. The second balance block 41 is symmetrically offset from the first balance block 11. A transmission assembly 5 is positioned between the main shaft 1 and the balance shaft 4. The main shaft 1 drives the balance shaft 4 to rotate via the transmission assembly 5, and the balance shaft 4 rotates in the opposite direction to the main shaft 1. The symmetrical offset arrangement of the first balance block 11 means that the projections of the first balance block 11 and the second balance block 41 do not overlap in the front-back direction, but when the first balance block 11 moves to a relative position, the first balance block 11 and the second balance block 41 are in a relatively symmetrical state. In this embodiment, the front-back direction is Figure 1 Center Y direction.
[0038] When the main shaft 1 is driven counterclockwise by the sewing machine motor, the main shaft 1 drives the balance shaft 4 to rotate clockwise in the opposite direction via the transmission assembly 5. The crank drives the needle bar assembly 3 to move up and down via the needle bar crank slider assembly 2. During this process, since the first balance block 11 is set at 180° with the crank about the main shaft 1, and the first balance block and the second balance block 41 are arranged symmetrically, the needle bar assembly 3 is in a downward state when the first balance block 11 and the second balance block 41 move upward. This makes the movement directions of the balance block and the needle bar assembly 3 opposite, thus effectively balancing the dynamic imbalance caused by the movement of the needle bar assembly 3. Since the first balance block 11 is arranged on the main shaft 1, it is easy to arrange and will not occupy the space of the needle bar slider 24, thereby reducing operating noise. Since the first balance block 11 and the second balance block 41 are staggered and symmetrically arranged and rotate in opposite directions, they can balance the inertial forces in the front and back directions of the needle bar piercing structure. This allows the imbalance in the movement of the first balance block 11 and the second balance block 41 to cancel each other out through their opposite movements, reducing vibration in the front and back directions and improving the overall stability of the movement.
[0039] In some embodiments, the transmission assembly 5 includes a driving gear 51 and a driven gear 52. The driving gear 51 is fixedly sleeved on the main shaft 1, and the driven gear 52 is fixedly sleeved on the balance shaft 4, with the driving gear 51 meshing with the driven gear 52. During the rotation of the main shaft 1 driven by the sewing machine's motor, the driving gear 51 rotates synchronously with the main shaft 1, driving the driven gear 52 to rotate. The driven gear 52 then drives the balance shaft 4 to rotate, which in turn drives the second balance block 41 to rotate, thus achieving a balancing effect in the front-to-back direction and ensuring the stability of the movement. In this embodiment, both the driving gear 51 and the driven gear 52 are helical gears. Helical gear transmission offers high transmission smoothness, with progressive meshing of the tooth surfaces (not the instantaneous line contact of spur gears), significantly reducing impact and noise, and meeting the needs of high-speed transmission. Under the same transmission ratio, the diameter of the helical gear can be smaller, or it can transmit higher torque within the same size, contributing to the miniaturization design of the sewing machine. In other embodiments, the driving gear 51 and the driven gear 52 can also be spur gears, without further limitations.
[0040] In some embodiments, the crank includes a thread take-up crank portion 22 and a needle bar crank portion 21 connected to each other. The needle bar crank portion 21 is connected to one end of the main shaft 1, and the thread take-up crank portion 22 is rotatably connected to the needle bar connecting rod 23. By designing the crank as a thread take-up crank portion 22 and a needle bar crank portion 21, the machining accuracy can be determined according to the machining requirements, thereby ensuring economy. Moreover, if one of the thread take-up crank portion 22 or the needle bar crank portion 21 becomes worn, it can be quickly replaced, avoiding the scrapping of the entire crank.
[0041] In some embodiments, the needle bar punching structure further includes a slide rail 25, which is fixedly disposed within the housing 100, and the needle bar slider 24 is slidably disposed on the slide rail 25. By providing the slide rail 25, the movement of the needle bar slider 24 can be constrained and guided, thereby ensuring the stability of the needle bar assembly 3 moving up and down in the vertical direction. In other embodiments, a guide groove can also be directly formed on the housing 100, and the needle bar slider 24 can also ensure the stability of the movement of the needle bar assembly 3 by cooperating with the guide groove.
[0042] In some embodiments, a first bushing 42 and a second bushing 43 are fitted at both ends of the balance shaft 4, allowing the balance shaft 4 to rotate relative to the first bushing 42 and the second bushing 43. The first bushing 42 and the second bushing 43 are fixedly connected to the housing 100. By providing the first bushing 42 and the second bushing 43, the balance shaft 4 is installed inside the housing 100. The first bushing 42 and the second bushing 43 ensure that the balance shaft 4 remains stable relative to the main shaft 1. To reduce friction during the rotation of the balance shaft 4, lubricating oil can be applied to the inside of the first bushing 42 and the second bushing 43, thereby improving the flexibility of the balance shaft 4's rotation.
[0043] In some embodiments, a first spindle sleeve 12 and a second spindle sleeve 13 are spaced apart on the spindle 1, allowing the spindle 1 to rotate relative to the first spindle sleeve 12 and the second spindle sleeve 13. The first spindle sleeve 12 and the second spindle sleeve 13 are fixedly connected to the housing 100. By providing the first spindle sleeve 12 and the second spindle sleeve 13, the spindle 1 is installed inside the housing 100. The first spindle sleeve 12 and the second spindle sleeve 13 ensure the stability of the spindle 1's position relative to the balance shaft 4. To reduce friction during spindle 1 rotation, lubricating oil can be applied to the inside of the first spindle sleeve 12 and the second spindle sleeve 13, thereby improving the flexibility and smoothness of spindle 1 rotation.
[0044] In some embodiments, the needle bar assembly 3 includes a needle bar body 31, a first needle bar bushing 32, and a second needle bar bushing 33. The needle bar body 31 is vertically arranged, and the first needle bar bushing 32 and the second needle bar bushing 33 are spaced apart and sleeved on the needle bar body 31. The needle bar body 31 is slidable relative to the first needle bar bushing 32 and the second needle bar bushing 33. The needle bar body 31 is connected to a needle bar slider 24, and the first needle bar bushing 32 and the second needle bar bushing 33 are fixedly connected to the housing 100. By providing the first needle bar bushing 32 and the second needle bar bushing 33, the movement of the needle bar body 31 can be constrained, and the vertical movement of the needle bar body 31 can be guided, ensuring the stability of the movement of the needle bar body 31. In this embodiment, the vertical direction is... Figure 1 The Z-direction in the middle.
[0045] In some embodiments, a needle bar connector 241 is provided on the needle bar slider 24, and the needle bar connector 241 is connected to the needle bar body 31. In this embodiment, the needle bar connector 241 is a clamp, and the needle bar connector 241 is fixedly sleeved on the needle bar body 31. During the process of the crank driving the needle bar slider 24 to move up and down relative to the slide rail 25, the needle bar slider 24 drives the needle bar body 31 to move up and down through the needle bar connector 241.
[0046] In some embodiments, a needle 34 is provided at the lower end of the needle bar body 31. During the up-and-down movement of the needle bar body 31, the needle 34 can be driven to move up and down, thereby completing the sewing action.
[0047] The working process of this needle bar piercing structure is as follows:
[0048] When the main shaft 1 rotates counterclockwise, it synchronously drives the drive gear 51, the first balance block 11, and the crank to rotate counterclockwise. The drive gear 51, through meshing, drives the driven gear 52 to rotate clockwise, which in turn drives the balance shaft 4 and the second balance block 41 to rotate clockwise synchronously. Simultaneously, the counterclockwise rotation of the crank causes the needle bar slider 24 to reciprocate up and down within the slide rail 25. The up-and-down movement of the needle bar slider 24 is further transmitted to the needle bar connector 241, causing the needle bar body 31, which is fixedly connected to the needle bar connector 241, to synchronously reciprocate up and down under the guidance of the first needle bar bushing 32 and the second needle bar bushing 33. The needle 34 then moves up and down synchronously, completing the sewing action.
[0049] To verify the dynamic balance optimization effect of the needle bar piercing structure, the improved structure and the original structure were simulated and analyzed using Recurdyn dynamic simulation software. The vibration amplitude of the new structure was significantly reduced compared with the original structure, with the Y-axis vibration decreasing by 32.03% and the Z-axis vibration decreasing by 12.36%. This fully verifies that the structure of this application can effectively improve the dynamic imbalance problem of the system, significantly reduce the vibration amplitude, and improve the operational stability.
[0050] This application also provides a sewing machine including the needle bar needle-punching structure as described above, which can reduce operating noise and balance the inertial forces in the front-to-back direction of the needle bar needle-punching structure, thereby reducing vibration in the front-to-back direction.
[0051] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. Those skilled in the art can make other variations or modifications based on the above description. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.
Claims
1. A needle bar pierced fabric structure, characterized in that, include: Main shaft (1), on which a first balance block (11) is fixedly mounted; Needle bar crank slider assembly (2), wherein the crank of the needle bar crank slider assembly (2) is connected to one end of the main shaft (1), and the first balance block (11) is set at 180° with the crank about the main shaft (1); Needle bar assembly (3), the needle bar slider (24) of the needle bar crank slider assembly (2) is connected to the needle bar assembly (3), and the needle bar slider (24) is rotatably connected to the crank through the needle bar connecting rod (23); A balance shaft (4) is arranged parallel to and spaced apart from the main shaft (1). A second balance block (41) is fixedly arranged on the balance shaft (4). The second balance block (41) is arranged symmetrically and offset from the first balance block (11). A transmission assembly (5) is disposed between the main shaft (1) and the balance shaft (4). The main shaft (1) drives the balance shaft (4) to rotate through the transmission assembly (5), and the balance shaft (4) rotates in the opposite direction to the main shaft (1).
2. The needle bar piercing structure according to claim 1, characterized in that, The transmission assembly (5) includes a drive gear (51) and a driven gear (52). The drive gear (51) is fixedly sleeved on the main shaft (1), and the driven gear (52) is fixedly sleeved on the balance shaft (4). The drive gear (51) meshes with the driven gear (52).
3. The needle bar piercing structure according to claim 1, characterized in that, The crank includes a thread take-up crank (22) and a needle bar crank (21) connected to each other. The needle bar crank (21) is connected to one end of the main shaft (1), and the thread take-up crank (22) is rotatably connected to the needle bar connecting rod (23).
4. The needle bar punched fabric structure according to any one of claims 1-3, characterized in that, It also includes a slide rail (25), which is fixedly installed inside the housing (100), and the needle bar slider (24) is slidably installed on the slide rail (25).
5. The needle bar punched fabric structure according to any one of claims 1-3, characterized in that, The balance shaft (4) is fitted with a first bushing (42) and a second bushing (43) at both ends. The balance shaft (4) can rotate relative to the first bushing (42) and the second bushing (43). The first bushing (42) and the second bushing (43) are fixedly connected to the housing (100).
6. The needle bar punched fabric structure according to any one of claims 1-3, characterized in that, The main shaft (1) is provided with a first main shaft sleeve (12) and a second main shaft sleeve (13) at intervals. The main shaft (1) can rotate relative to the first main shaft sleeve (12) and the second main shaft sleeve (13). The first main shaft sleeve (12) and the second main shaft sleeve (13) are fixedly connected to the housing (100).
7. The needle bar punched fabric structure according to any one of claims 1-3, characterized in that, The needle bar assembly (3) includes a needle bar body (31), a first needle bar bushing (32), and a second needle bar bushing (33). The needle bar body (31) is arranged vertically. The first needle bar bushing (32) and the second needle bar bushing (33) are spaced and sleeved on the needle bar body (31). The needle bar body (31) can slide relative to the first needle bar bushing (32) and the second needle bar bushing (33). The needle bar body (31) is connected to the needle bar slider (24). The first needle bar bushing (32) and the second needle bar bushing (33) are fixedly connected to the housing (100).
8. The needle bar piercing structure according to claim 7, characterized in that, The needle bar slider (24) is provided with a needle bar connector (241), which is connected to the needle bar body (31).
9. The needle bar piercing structure according to claim 7, characterized in that, The lower end of the needle bar body (31) is provided with an organic needle (34).
10. A sewing machine, characterized in that, Includes the needle bar piercing structure as described in any one of claims 1-9.