A needle bar motion noise reduction device and a sewing machine

Abstract

The utility model provides a needle bar motion reduces the device and sewing machine of making an uproar, needle bar motion reduces the device for setting in sewing machine reduces the impact and noise of needle bar motion, including upper repulsion mechanism, lower repulsion mechanism and intermediate force receiving mechanism, the intermediate force receiving mechanism is fixed with needle bar in needle bar axial, upper repulsion mechanism and lower repulsion mechanism are fixed respectively and set in the upper side and lower side of intermediate force receiving mechanism along needle bar axial, when the intermediate force receiving mechanism moves towards upper repulsion mechanism, upper repulsion mechanism can produce the repulsion of downwards to intermediate force receiving mechanism, and when the distance of both reduces, repulsion increases, when the intermediate force receiving mechanism moves towards lower repulsion mechanism, lower repulsion mechanism can produce the repulsion of upwards to intermediate force receiving mechanism, and when the distance of both reduces, repulsion increases.

Description

Technical Field

[0001] This utility model relates to the field of sewing machine technology, specifically to a needle bar noise reduction device and a sewing machine. Background Technology

[0002] In a sewing machine, the needle bar drive mechanism transmits the motion of the drive source (such as the spindle or motor) to the needle bar, causing the needle to move up and down in a reciprocating motion. A commonly used needle bar drive mechanism is the crank-slider mechanism; the main structure of the crank-slider mechanism is shown in the appendix. Figure 1 As shown, it mainly includes a crank, a connecting rod, and a fixed block. The fixed block is fixedly connected to the needle bar. The crank is sleeved and fixed to the main shaft. The two ends of the connecting rod are rotatably connected to the crank and the fixed block, respectively. The rotation of the main shaft drives the crank to rotate, the crank drives the connecting rod to move, and the connecting rod drives the needle bar to reciprocate along the axial direction through the fixed block.

[0003] Because there are clearances at the joints of the components in the needle bar transmission mechanism—for example, between the connecting rod and the crank, and between the connecting rod and the fixed block—these components will collide back and forth within these clearances during the up-and-down movement of the needle bar. The principle of this collision during turning is explained in the appendix. Figure 2 As shown: In the needle bar drive mechanism, before the needle bar turns, the driving member closely follows the driven member (e.g., between a connecting rod and a fixed block, where the connecting rod is the driving member and the fixed block is the driven member), driving the driven member to move at a speed of V1. During the turning process, the driving member decelerates from V1 to 0, and then accelerates from 0 to V3 to complete the turning. During the deceleration and turning process of the driving member, the driven member continues to move towards the driving member at a speed of V2 due to inertia, and then collides with the driving member. After the collision, it is driven by the driving member to complete the turning process and moves together with the driving member at a speed of V3. Therefore, the needle bar drive mechanism generates considerable noise during operation, and also places a significant load on the motor during the acceleration and deceleration of the needle bar, affecting the operation of the sewing machine. Utility Model Content

[0004] In view of the shortcomings of the prior art described above, the technical problem to be solved by this utility model is to provide a needle bar noise reduction device and a sewing machine, which can effectively reduce the collision impact between moving parts during needle bar operation, achieve noise reduction and vibration reduction effect, and reduce the load on the drive source during turning.

[0005] To achieve the above objectives, this utility model provides a needle bar noise reduction device for use in sewing machines to reduce the impact and noise of needle bar movement. It includes an upper repulsion mechanism, a lower repulsion mechanism, and an intermediate force-receiving mechanism. The intermediate force-receiving mechanism is fixed to the needle bar along its axial direction. The upper and lower repulsion mechanisms are respectively fixed to the upper and lower sides of the intermediate force-receiving mechanism along the needle bar's axial direction. When the intermediate force-receiving mechanism moves towards the upper repulsion mechanism, the upper repulsion mechanism generates a downward repulsive force on the intermediate force-receiving mechanism, and the repulsive force increases as the distance between them decreases. When the intermediate force-receiving mechanism moves towards the lower repulsion mechanism, the lower repulsion mechanism generates an upward repulsive force on the intermediate force-receiving mechanism, and the repulsive force increases as the distance between them decreases.

[0006] Furthermore, the repulsive force between the intermediate force-receiving mechanism and the upper repulsive force-receiving mechanism is inversely proportional to the horizontal distance between them, and the repulsive force between the intermediate force-receiving mechanism and the lower repulsive force-receiving mechanism is inversely proportional to the horizontal distance between them.

[0007] Furthermore, the intermediate force-bearing mechanism includes an intermediate magnetic component, the upper repulsion mechanism includes an upper magnetic component, and the lower repulsion mechanism includes a lower magnetic component. Both the upper and lower magnetic components generate electromagnetic repulsion with the intermediate magnetic component.

[0008] Furthermore, the upper magnetic component, lower magnetic component, and middle magnetic component are all permanent magnets.

[0009] Furthermore, the upper magnetic component, lower magnetic component, and middle magnetic component are all electromagnets.

[0010] Furthermore, the upper magnetic component, lower magnetic component, and middle magnetic component are all located next to the needle bar, and the upper magnetic component, lower magnetic component, and middle magnetic component are located on a straight line parallel to the needle bar.

[0011] Furthermore, the upper magnetic component, lower magnetic component, and middle magnetic component are all annular and are sleeved on the outside of the needle bar.

[0012] This utility model also provides a sewing machine, including a needle bar and a needle bar transmission mechanism. The needle bar transmission mechanism is connected to the needle bar and is used to drive the needle bar to move axially. It also includes the aforementioned needle bar movement noise reduction device.

[0013] Furthermore, the center of mass of the needle bar transmission mechanism is located on a straight line parallel to the needle bar during movement.

[0014] Furthermore, the needle bar transmission mechanism includes a crank, a connecting rod, and a fixed block. The fixed block is fixedly connected to the needle bar. One end of the crank is fixed to the main shaft, and both ends of the connecting rod are rotatably connected to the crank and the fixed block, respectively. The intermediate force-bearing mechanism of the needle bar motion noise reduction device is installed on the fixed block.

[0015] As described above, the needle bar noise reduction device and sewing machine involved in this utility model have the following beneficial effects:

[0016] 1. When the needle bar moves to its upper and lower limit positions and turns, it can provide a corresponding repulsive force to reduce the inertial motion of the driven part in the two connected moving parts of the needle bar and the needle bar transmission mechanism, reduce its speed, thereby reducing the collision intensity between the driven part and the driving part, and further reducing the noise and vibration of the overall transmission mechanism; at the same time, after the needle bar completes the turning, the repulsive force can also provide positive gain to the movement of the needle bar and the needle bar transmission mechanism, which can help the drive source reduce the load.

[0017] 2. Electromagnetic repulsion is used between the upper and lower repulsion mechanisms and the intermediate force-bearing mechanism. This allows for good control of the magnitude of the repulsion force and enables the needle bar to generate a large repulsion force only when it is close to the upper and lower limit positions. At other times, it generates only a weak repulsion force or no repulsion force. This buffers the mechanism during turning without affecting the rest of the mechanism's movement, allowing the needle bar to operate normally near the intermediate position.

[0018] 3. The needle bar noise reduction device uses permanent magnets to generate electromagnetic repulsion, which is simple in structure, low in cost, and has no additional energy consumption or noise.

[0019] 4. By optimizing the counterweight of the needle bar transmission mechanism, its center of mass is positioned on a straight line parallel to the needle bar during movement, thereby amplifying the buffering effect brought by the magnetic repulsion of the needle bar movement noise reduction device. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of an existing needle bar drive mechanism.

[0021] Figure 2 This is a schematic diagram illustrating the collisions and noise generated during the movement of the needle bar in an existing needle bar transmission mechanism.

[0022] Figure 3 This is a schematic diagram of the structure of the needle bar noise reduction device of this utility model.

[0023] Figure 4 This is a schematic diagram illustrating the working principle of the needle bar noise reduction device of this utility model.

[0024] Explanation of icon numbers:

[0025] 1-Main shaft, 2-Crank, 3-Connecting rod, 4-Fixed block, 5-Needle rod, 6-Driving component, 7-Driven component, 8-Intermediate magnetic component, 9-Upper magnetic component, 10-Lower magnetic component, 11-Machining housing. Detailed Implementation

[0026] The following specific embodiments illustrate the implementation of this utility model. Those skilled in the art can easily understand other advantages and effects of this utility model from the content disclosed in this specification.

[0027] 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 to facilitate understanding. They are not intended to limit the scope of this invention and therefore have no substantial technical significance. Any modifications to the structure, changes in proportions, or adjustments to size, provided they do not affect the effectiveness or purpose of this invention, should still fall within the scope of the technical content disclosed herein. Furthermore, terms such as "upper," "lower," "left," "right," and "middle" 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.

[0028] See Figures 1 to 4 This utility model provides a needle bar movement noise reduction device, which is used to reduce the impact and noise of the needle bar 5 movement in a sewing machine. The needle bar movement noise reduction device includes an upper repulsion mechanism, a lower repulsion mechanism, and an intermediate force receiving mechanism. The intermediate force receiving mechanism is fixed to the needle bar 5 along the axial direction of the needle bar 5. The upper repulsion mechanism and the lower repulsion mechanism are respectively fixed on the upper and lower sides of the intermediate force receiving mechanism along the axial direction of the needle bar 5. When the intermediate force receiving mechanism moves toward the upper repulsion mechanism, the upper repulsion mechanism can generate a downward repulsion force on the intermediate force receiving mechanism, and the repulsion force increases when the distance between the two decreases. When the intermediate force receiving mechanism moves toward the lower repulsion mechanism, the lower repulsion mechanism generates an upward repulsion force on the intermediate force receiving mechanism, and the repulsion force increases when the distance between the two decreases.

[0029] This utility model discloses a needle bar movement noise reduction device, used to reduce the impact and noise generated when the needle bar transmission mechanism drives the needle bar 5 to move, especially when the needle bar 5 turns at its upper and lower limit positions. See also Figure 1 and Figure 3 The needle bar drive mechanism connects the needle bar 5 and the drive source. The drive source can be a main shaft 1 or a motor, etc. The needle bar drive mechanism generally includes multiple moving components, such as a crank 2, a connecting rod 3, and a fixed block 4. In the motion chain from the main shaft 1 to the needle bar 5, of the two connected moving parts, one is the driving component 6, and the other is the driven component 7. Taking the connecting rod 3 and the fixed block 4 as an example, the connecting rod 3 is the driving component 6, and the fixed block 4 is the driven component 7. (See also...) Figure 4When the needle bar 5 moves to its upper limit position, it drives the intermediate force-receiving mechanism to move towards the upper repulsive mechanism. The upper repulsive mechanism generates a downward repulsive force F on the intermediate force-receiving mechanism, and F gradually increases. When the needle bar 5 approaches its upper limit position, the repulsive force F reaches a large value, which significantly hinders the inertial motion of the driven member 7, i.e., provides a deceleration, reduces the velocity V2 of the driven member 7, thereby reducing the collision intensity between the driven member 7 and the driving member 6, and further reducing the overall noise and vibration of the mechanism. Subsequently, when the needle bar 5 completes its downward acceleration at the upper limit position, the downward repulsive force F generated by the upper repulsive mechanism on the intermediate force-receiving mechanism is a positive gain for the needle bar 5, which can help the drive source reduce the load. Similarly, when the needle bar 5 moves to its lower limit position, it drives the intermediate force-bearing mechanism to move towards the lower repulsion mechanism. At this time, the upward repulsion force F generated by the lower repulsion mechanism on the intermediate force-bearing mechanism gradually increases, and reaches a large value when approaching the lower limit position. This hinders the inertial motion of the driven member 7 and provides positive gain when completing the upward turning motion. Therefore, the needle bar motion noise reduction device can effectively buffer and reduce noise when the needle bar 5 turns, and reduce the load on the drive source during turning.

[0030] See Figures 1 to 4 The present invention will be further described below with reference to specific embodiments:

[0031] See Figure 3 In this embodiment, as a preferred design, the intermediate force-bearing mechanism includes an intermediate magnetic component 8, the upper repulsion mechanism includes an upper magnetic component 9, and the lower repulsion mechanism includes a lower magnetic component 10. Both the upper magnetic component 9 and the lower magnetic component 10 generate electromagnetic repulsion with the intermediate magnetic component 8, and at this time, both the upper magnetic component 9 and the lower magnetic component 10 have a suitable distance from the intermediate magnetic component 8. This makes the repulsion between the intermediate force-bearing mechanism and the upper repulsion mechanism inversely proportional to the distance between them when they are laid flat, and the repulsion between the intermediate force-bearing mechanism and the lower repulsion mechanism inversely proportional to the distance between them when they are laid flat. With this design, the needle bar 5 can generate a large repulsion force rapidly only when it is close to the upper and lower limit positions, and only a weak repulsion force at other times. This buffers the mechanism when turning without affecting the rest of the mechanism's movement, allowing the needle bar 5 to operate normally near the intermediate position.

[0032] See Figure 3In this embodiment, as a preferred design, the upper magnetic component 9, the lower magnetic component 10, and the middle magnetic component 8 are all permanent magnets. The upper magnetic component 9 and the middle magnetic component 8 have their like poles facing each other, for example, their S poles facing each other, while the lower magnetic component 10 and the middle magnetic component 8 have their N poles facing each other. This design is simple and can stably generate repulsive force. When the needle bar 5 moves to its upper limit position, the distance H1 between the middle magnetic component 8 and the upper magnetic component 9 is preferably 0~1mm. When the needle bar 5 moves to its lower limit position, the distance H2 between the middle magnetic component 8 and the lower magnetic component 10 is selected to be 0~1mm. This design is compact and reduces the impact on the installation of parts on the sewing machine at this point.

[0033] In another embodiment, as a preferred design, the upper magnetic component 9, the lower magnetic component 10, and the middle magnetic component 8 can also be electromagnets, generating magnetic force only when energized. Using electromagnets allows for continuous energization to maintain magnetic force, or it can be de-energized and energized only near the upper and lower limit positions of the needle bar 5, generating electromagnetic repulsion. Within a certain range above and below the middle position of the needle bar 5, it can be de-energized, i.e., without magnetic force, thus not affecting the normal operation of the needle bar 5 at the middle position.

[0034] See Figure 3 In this embodiment, more preferably, the upper magnetic component 9, the lower magnetic component 10, and the middle magnetic component 8 are all disposed next to the needle bar 5, and the upper magnetic component 9, the lower magnetic component 10, and the middle magnetic component 8 are located on a straight line parallel to the needle bar 5, so that the upper magnetic component 9, the middle magnetic component 10, and the lower magnetic component 10 remain vertically opposite each other along the axial direction of the needle bar 5, thereby ensuring that the generated electromagnetic repulsion force is along the axial direction of the needle bar 5 and avoiding the generation of a bias force.

[0035] In another embodiment, the upper magnetic component 9, the lower magnetic component 10, and the middle magnetic component 8 can all be annular, preferably circular, and are all coaxially sleeved on the outside of the needle bar 5. This ensures that the upper magnetic component 9, the middle magnetic component, and the lower magnetic component 10 are kept vertically opposite each other along the axial direction of the needle bar 5, thereby ensuring that the generated electromagnetic repulsion force is along the axial direction of the needle bar 5 and avoiding the generation of a bias force.

[0036] In other embodiments, the upper repulsion mechanism, the lower repulsion mechanism, and the intermediate force receiving mechanism may also adopt other suitable mechanisms. The repulsion force generated may be electromagnetic force, elastic force, or pressure, as long as it can generate a repulsion force in the corresponding direction on the intermediate force receiving mechanism.

[0037] See Figure 1 and 2 This utility model provides a sewing machine, including a needle bar 5 and a needle bar transmission mechanism. The needle bar transmission mechanism is connected to the needle bar 5 and is used to drive the needle bar 5 to move axially. It also includes the aforementioned needle bar movement noise reduction device.

[0038] In this embodiment, see Figure 1 and 3 The needle bar transmission mechanism includes a crank 2, a connecting rod 3, and a fixing block 4. The fixing block 4 is fixedly connected to the needle bar 5. One end of the crank 2 is fixed to the main shaft 1. Specifically, the crank 2 is sleeved on a pin on the crank 2 through a shaft hole, achieving a rotatable connection. Both ends of the connecting rod 3 are rotatably connected to the crank 2. Specifically, both ends of the connecting rod 3 are sleeved on pins on the crank 2 and pins on the fixing block 4 through shaft holes. The intermediate magnetic component 8 of the intermediate force-bearing mechanism of the needle bar movement noise reduction device is installed on the fixing block 4, without affecting the movement and replacement of the needle bar 5. Of course, the intermediate magnetic component 8 can also be directly fixed to the needle bar 5. The upper magnetic component 9 and the lower magnetic component 10 can both be fixedly installed in the sewing machine housing 11. The needle bar motion noise reduction device effectively reduces the impact vibration and noise generated when the main shaft 1 and the needle bar transmission mechanism drive the needle bar 5, especially the motion impact vibration and noise caused by the fit clearance between the main shaft 1 and the crank 2, between the crank 2 and the connecting rod 3, and between the connecting rod 3 and the fixed block 4. The needle bar transmission mechanism is not limited to the above structural design. In other embodiments, the needle bar transmission mechanism can also adopt other suitable structural designs, as long as it can effectively drive the needle bar 5. For needle bar transmission mechanisms with other structural designs, the needle bar motion noise reduction device can also reduce impact vibration and noise.

[0039] In this embodiment, see Figure 1 and 3 Preferably, the crank 2, connecting rod 3, and fixed block 4 of the needle bar transmission mechanism are designed so that the overall center of mass of the needle bar transmission mechanism is located on a straight line parallel to the needle bar 5 during movement. Furthermore, the overall center of mass of the needle bar transmission mechanism is located on the central axis of the needle bar 5, so that there is no deviation or only a slight deviation in the horizontal direction. This concentrates the impact of the needle bar transmission mechanism during movement in the axial direction of the needle bar 5, amplifying the buffering, noise reduction, and shock absorption effect of the needle bar movement noise reduction device.

[0040] The needle bar noise reduction device and sewing machine of this utility model have the following beneficial effects:

[0041] 1. When the needle bar 5 moves to the upper and lower limit positions and turns, it can provide a corresponding repulsive force to reduce the inertial motion of the needle bar 5 and the driven part 7 in the two connected moving parts of the needle bar transmission mechanism, reduce its speed, thereby reducing the collision intensity between the driven part 7 and the driving part 6, and further reducing the noise and vibration of the overall transmission mechanism; at the same time, after the needle bar 5 completes the turning, the repulsive force can provide positive gain for the movement of the needle bar 5 and the needle bar transmission mechanism, which can help the drive source reduce the load.

[0042] 2. Electromagnetic repulsion is used between the upper and lower repulsion mechanisms and the intermediate force-bearing mechanism. This can effectively control the magnitude of the repulsion force and allow the needle bar 5 to generate a large repulsion force only when it is close to the upper and lower limit positions. At other times, it generates only a weak repulsion force or no repulsion force. This buffers the mechanism during turning without affecting the rest of the mechanism's movement, allowing the needle bar 5 to operate normally near the intermediate position.

[0043] 3. The needle bar noise reduction device uses permanent magnets to generate electromagnetic repulsion, which is simple in structure, low in cost, and has no additional energy consumption or noise.

[0044] 4. By optimizing the counterweight of the needle bar transmission mechanism, its center of mass is positioned on a straight line parallel to the needle bar 5 during movement, thereby amplifying the buffering effect brought by the magnetic repulsion of the needle bar movement noise reduction device.

[0045] In summary, this utility model effectively overcomes the various shortcomings of the prior art and has high industrial application value.

[0046] The above embodiments are merely illustrative of the principles and effects of this utility model and are not intended to limit the scope of this utility model. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of this utility model. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in this utility model should still be covered by the claims of this utility model.

Claims

1. A needle bar noise reduction device, used in a sewing machine to reduce the impact and noise of the needle bar (5) movement, characterized in that: It includes an upper repulsion mechanism, a lower repulsion mechanism, and an intermediate force receiving mechanism. The intermediate force receiving mechanism is fixed to the needle bar (5) along the axial direction of the needle bar (5). The upper repulsion mechanism and the lower repulsion mechanism are respectively fixedly arranged on the upper and lower sides of the intermediate force receiving mechanism along the axial direction of the needle bar (5). When the intermediate force receiving mechanism moves toward the upper repulsion mechanism, the upper repulsion mechanism can generate a downward repulsion force on the intermediate force receiving mechanism, and the repulsion force increases when the distance between the two decreases. When the intermediate force receiving mechanism moves toward the lower repulsion mechanism, the lower repulsion mechanism can generate an upward repulsion force on the intermediate force receiving mechanism, and the repulsion force increases when the distance between the two decreases.

2. The needle bar movement noise reduction device according to claim 1, characterized in that: The repulsive force between the intermediate force-receiving mechanism and the upper repulsive force-receiving mechanism is inversely proportional to the horizontal distance between them, and the repulsive force between the intermediate force-receiving mechanism and the lower repulsive force-receiving mechanism is inversely proportional to the horizontal distance between them.

3. The needle bar movement noise reduction device according to claim 1 or 2, characterized in that: The intermediate force-bearing mechanism includes an intermediate magnetic component (8), the upper repulsion mechanism includes an upper magnetic component (9), and the lower repulsion mechanism includes a lower magnetic component (10). The upper magnetic component (9) and the lower magnetic component (10) both generate electromagnetic repulsion with the intermediate magnetic component (8).

4. The needle bar movement noise reduction device according to claim 3, characterized in that: The upper magnetic component (9), lower magnetic component (10) and middle magnetic component (8) are all permanent magnets.

5. The needle bar movement noise reduction device according to claim 3, characterized in that: The upper magnetic component (9), lower magnetic component (10) and middle magnetic component (8) are all electromagnets.

6. The needle bar movement noise reduction device according to claim 3, characterized in that: The upper magnetic component (9), lower magnetic component (10) and middle magnetic component (8) are all located next to the needle bar (5), and the upper magnetic component (9), lower magnetic component (10) and middle magnetic component (8) are located on a straight line parallel to the needle bar (5).

7. The needle bar movement noise reduction device according to claim 3, characterized in that: The upper magnetic component (9), lower magnetic component (10) and middle magnetic component (8) are all annular and are sleeved outside the needle bar (5).

8. A sewing machine, comprising a needle bar (5) and a needle bar transmission mechanism, wherein the needle bar transmission mechanism is connected to the needle bar (5) and is used to drive the needle bar (5) to move axially, characterized in that: It also includes the needle bar noise reduction device as described in any one of claims 1 to 7.

9. The sewing machine according to claim 8, characterized in that: When the needle bar transmission mechanism is in motion, its overall center of mass moves along a straight line parallel to the needle bar (5).

10. The sewing machine according to claim 8 or 9, characterized in that: The needle bar transmission mechanism includes a crank (2), a connecting rod (3) and a fixed block (4). The fixed block (4) is fixedly connected to the needle bar (5). One end of the crank (2) is fixed to the main shaft (1). Both ends of the connecting rod (3) are rotatably connected to the crank (2) and the fixed block (4) respectively. The intermediate force-bearing mechanism of the needle bar motion noise reduction device is installed on the fixed block (4).

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