A presser foot device for a sewing machine

Abstract

The utility model relates to a kind of presser foot device and sewing machine application, presser foot device includes presser foot body, respectively with the guiding mechanism and fixed through slot for adhesive tape sequentially passing and be connected with the presser foot body, wherein, the presser foot body includes with the main support connected with sewing machine, the presser foot plate that recessed through slot is opened, the support arm of connecting the main support and presser foot plate, the guiding mechanism includes extension and meander, the extension is connected with the support arm, the meander is located the oblique upper side of fixed through slot entrance end and is used for the adhesive tape to pass through;The fixed through slot is located at the presser foot plate, and the opening direction is consistent with the opening direction of recessed through slot on the presser foot plate. Compared with prior art, the utility model can realize the stable positioning of adhesive tape, provide more uniform and stable tension for adhesive tape, and also reduce the possibility of wrinkling and fabric deformation during sewing.

Description

Technical Field

[0001] This utility model relates to the field of clothing technology, and in particular to a presser foot device and a sewing machine. Background Technology

[0002] In the manufacturing of clothing, bags, and footwear, the use of seam tape is a common process to enhance the waterproofness, durability, or aesthetics of products. However, in actual production, the seam tape sewing process faces many technical challenges, primarily in the fixation and tension control of the seam tape.

[0003] In traditional adhesive strip sewing processes, the soft, thin, and easily deformable nature of the adhesive strip makes it prone to problems such as misalignment, folding, or twisting during feeding and sewing. Furthermore, the material differences between the fabric and the adhesive strip result in different tensions and shrinkage rates during sewing, leading to quality defects such as wrinkling, deformation, or seam misalignment. These problems not only affect the product's appearance and function but can also reduce production efficiency and increase scrap rates.

[0004] In sewing, the fixing and tension control of the adhesive strip are crucial factors affecting the quality of the finished product. Due to the interaction between the flexibility of the adhesive strip and the fabric characteristics (such as elasticity and thickness differences), the following problems can easily occur during the sewing process:

[0005] (1) Difficulty in positioning the rubber strip: The rubber strip is prone to shifting, folding or twisting due to lack of effective fixation;

[0006] (2) Tension imbalance: The difference in shrinkage rate between the fabric and the adhesive strip leads to uneven local tension, causing wrinkles or seam displacement.

[0007] (3) Limitations of manual operation: Traditional manual force application relies on experience, which has problems such as poor matching between feeding speed and tension, and fluctuation of force application. It is easy to cause material deformation or seam breakage, and it is difficult to adapt to different materials (such as TPU strips requiring low tension and rubber-based strips requiring high tension).

[0008] CN215628628U discloses a template presser foot device for machining webbing and adhesive strips, which has an adhesive strip guide cavity to initially achieve automation, but still fails to solve the aforementioned problems. Utility Model Content

[0009] The purpose of this invention is to overcome the shortcomings of the existing technology, such as difficulty in positioning the rubber strip, tension imbalance, and operational limitations, by providing a presser foot device and a sewing machine.

[0010] The objective of this utility model can be achieved through the following technical solutions:

[0011] One of the technical solutions of this utility model is to provide a presser foot device, including a presser foot body, a guide mechanism connected to the presser foot body for sequential passage of adhesive strips, and a fixing groove.

[0012] The presser foot body includes a main support frame connected to the sewing machine, a presser foot plate with a recessed groove, and a support arm connecting the main support frame and the presser foot plate.

[0013] The guiding mechanism includes an extension and a bend, the extension being connected to the support arm, and the bend being located obliquely above the inlet end of the fixed through slot and used for the rubber strip to pass through;

[0014] The fixed through groove is located at the pressure foot plate, and its opening direction is consistent with the opening direction of the recessed through groove on the pressure foot plate.

[0015] In some specific embodiments, the angle between the bend and the vertical direction is 30° to 50°.

[0016] In some specific embodiments, an angle adjuster is provided between the extension and the bend for adjusting the angle between the bend and the vertical direction.

[0017] In some specific embodiments, the bend is composed of several U-shaped placement grooves connected end to end, which can accommodate the passage of the rubber strip.

[0018] In some specific embodiments, the U-shaped groove includes two parallel crossbars and a connecting arc connecting the crossbars, wherein the length of the crossbars is greater than the width of the adhesive strip.

[0019] In some specific embodiments, the relationship between the length DD' of the crossbar and the distance AC between two adjacent crossbars satisfies: Where BB' is the perpendicular distance between the two farthest points on the two connecting arcs, and R is the radius of the connecting arc.

[0020] In some specific embodiments, the spacing between two adjacent crossbars in the bend is consistent, and the length of each crossbar is also consistent.

[0021] In some specific embodiments, at least two U-shaped placement slots are provided.

[0022] In some specific embodiments, the width of the fixing groove is 0.1 mm to 0.5 mm greater than the thickness of the adhesive strip, and the length of the fixing groove is 0.1 mm to 0.5 mm greater than the width of the adhesive strip.

[0023] The second technical solution of this utility model is to provide a sewing machine, including the presser foot device as described in one of the above technical solutions.

[0024] Compared with the prior art, the present invention has the following beneficial effects:

[0025] (1) The presser foot device of this utility model is directly connected to the presser foot body. On the one hand, it is convenient to position the rubber strip, and on the other hand, it shortens the distance between the rubber strip and the sewing position, making it easier to control the stability of the rubber strip, thereby reducing the possibility of wrinkling and fabric deformation during sewing.

[0026] (2) The presser foot device of this utility model provides tension balance for the rubber strip during feeding and sewing. When the rubber strip passes through the guide mechanism, it is subjected to forces in both the bending direction and the extension direction, which can effectively prevent the rubber strip from curling or folding. Then, when passing through the fixed through groove, the rubber strip can be subjected to appropriate tension before entering the needle plate, ensuring that the rubber strip can pass smoothly while further satisfying the tension balance during sewing, and at the same time, it will not affect the operator's line of sight and operating space.

[0027] (3) Compared with the traditional manual tensioning method, the presser foot device of this utility model can provide more uniform and stable tension, reducing problems such as material deformation, thread breakage or adhesive strip failure caused by improper manual operation. At the same time, the operator can focus more on sewing quality rather than manually controlling the adhesive strip tension, thereby improving work efficiency and product quality.

[0028] (4) The presser foot device of this utility model is not only applicable to various types of adhesive strips, but also applicable to the sewing of other fabrics such as webbing. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the structure of this utility model.

[0030] Figure 2 This is a schematic diagram of the structure of the fixed through groove of this utility model.

[0031] Figure 3 This is a front view schematic diagram of the adhesive strip passing through the guide mechanism of this utility model.

[0032] Figure 4 This is a side view of the guide mechanism of this utility model showing the adhesive strip passing through it.

[0033] Figure 5 This is a schematic diagram of the guiding mechanism of this utility model.

[0034] The diagram is labeled as follows:

[0035] 1 is the main body of the presser foot, 101 is the main support frame, 102 is the support arm, and 103 is the presser foot plate;

[0036] 2 is a fixed through groove;

[0037] 3 is the guiding mechanism, 301 is the extension, 302 is the bend, 3021 is the U-shaped receiving groove, 30211 is the crossbar, and 30212 is the connecting arc.

[0038] 4 represents the rubber strip. Detailed Implementation

[0039] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. This embodiment is based on the technical solution of the present invention and provides detailed implementation methods and specific operating procedures; however, the scope of protection of the present invention is not limited to the following embodiments.

[0040] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0041] The following detailed description of some embodiments of the present invention is provided in conjunction with the accompanying drawings. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0042] In the following embodiments, unless otherwise specified, the functional components or structures are conventional components or structures used in the art to achieve the corresponding functions.

[0043] Example 1:

[0044] like Figures 1-5 As shown, this embodiment provides a presser foot device, including a presser foot body 1, a guide mechanism 3 connected to the presser foot body 1 for allowing the adhesive strip 4 to pass through sequentially, and a fixing groove 2.

[0045] The presser foot body 1 includes a main support 101 connected to a sewing machine, a presser foot plate 103 with a recessed through groove, and a support arm 102 connecting the main support 101 and the presser foot plate 103.

[0046] The guide mechanism 3 includes an extension 301 and a bend 302. The extension 301 is connected to the support arm 102, and the bend 302 is located obliquely above the inlet end of the fixed through groove 2 and is used for the rubber strip 4 to pass through.

[0047] The fixed through groove 2 is provided at the pressure foot plate 103, and its opening direction is consistent with the opening direction of the recessed through groove on the pressure foot plate 103.

[0048] In this technical solution, by directly connecting the guide mechanism 3 and the fixed through groove 2 to the pressure plate body 1, it facilitates the positioning of the adhesive strip 4 and shortens the distance between the adhesive strip 4 and the sewing position, making it easier to control the stability of the adhesive strip 4 and thus reducing the possibility of wrinkling and fabric deformation during sewing. In use, the adhesive strip 4 first passes through the bend 302 of the guide mechanism 3, which applies a uniform and moderate tension to the adhesive strip 4. This ensures that the adhesive strip 4 is subjected to forces in both the bend 302 direction and the extension 301 direction during passage, effectively preventing the adhesive strip 4 from curling or folding. Next, the adhesive strip 4 passes through the fixed through groove 2 before sewing. This allows the adhesive strip 4 to be subjected to appropriate tension before entering the needle plate, further ensuring tension balance during sewing without obstructing the operator's view or operating space. Compared to traditional manual assisted tension methods, this technical solution provides more uniform and stable tension, reducing problems such as material deformation, thread breakage, or adhesive strip 4 failure caused by improper manual operation. Meanwhile, the operator can focus more on sewing quality rather than manually controlling the tension of the adhesive strip 4, thereby improving work efficiency and product quality. This technical solution is not only applicable to the adhesive strip 4, but also to the sewing of other fabrics such as webbing.

[0049] like Figures 3-4 As shown, the guide mechanism 3 can be made of a metal wire with moderate elasticity, such as stainless steel wire, which provides sufficient support while also having a certain degree of elasticity. The extension 301 and the bending part 302 can be integrally formed, or an angle adjuster can be provided between them to ensure that the angle between the bending part 302 and the vertical direction is 30° to 50°. For different materials of the adhesive strip 4, the tension can be adjusted by adjusting the angle α between the bending part 302 and the vertical direction. For example, for materials such as TPU adhesive strips that require low tension, the tilt angle α can be adjusted to close to 30°; while for materials such as rubber-based adhesive strips that require high tension, the tilt angle α can be adjusted to close to 50°.

[0050] like Figures 3-4As shown, the bend 302 can be formed by bending one end of the metal wire back and forth to create multiple U-shaped slots 3021 that are connected end to end and can accommodate the passage of the adhesive strip 4. Each U-shaped slot 3021 has a structure that is closed on one side and open on the other side. This design facilitates the quick passage of the adhesive strip 4 or webbing and improves operating efficiency. The operator can adjust the tension by setting the number of corresponding U-shaped slots 3021 to be inserted using adhesive strips 4 of different thicknesses and elasticities. The number of U-shaped slots 3021 is at least two. For example, for materials such as TPU adhesive strips that require low tensile strength, the number of U-shaped slots 3021 needs to be reduced. Preferably, only two U-shaped slots 3021 can be interlaced. For materials such as rubber-based adhesive strips that require high tensile strength, the number of U-shaped slots 3021 needs to be increased. Preferably, four U-shaped slots 3021 can be interlaced. In actual use, the operator first passes the adhesive strip 4 or webbing through several U-shaped grooves 3021 one by one from the top of the bend 302. Due to the special design of the U-shaped grooves 3021 in this technical solution, the adhesive strip 4 will be naturally subjected to a uniform tension applied by the guide mechanism 3 when passing through.

[0051] like Figures 3-5 As shown, the U-shaped placement groove 3021 includes two parallel crossbars 30211 and a connecting arc 30212 connecting the crossbars 30211. The length of the crossbars 30211, i.e. the width W2 of the U-shaped placement groove 3021, is greater than the width of the adhesive strip 4 or webbing, which can prevent wrinkles from appearing in the adhesive strip 4 or webbing during the sewing process and ensure smooth sewing.

[0052] like Figure 5 As shown, line segment BB' represents the maximum width of the U-shaped groove 3021, meaning points B and B' are located on two adjacent connecting arcs 30212. Line segment DD' represents the width W2 of the U-shaped groove 3021 excluding the connecting arcs 30212, which is the width of the crossbar 30211, satisfying BD = B'D'. Therefore, W2 = BB' - 2BD. Points A and C are located at the junction of the crossbar 30211 and the connecting arc 30212. Line segment AC represents the spacing L2 of the U-shaped groove 3021, satisfying that point D is also on line segment AC. Let the radius of the connecting arc ABC be R and the center be O. Therefore, OA = OB = OC = R, and AD = CD = AC / 2. Based on geometric relationships, the following calculations are obtained: Therefore, it can be concluded that Ultimately, U describes the width W2 of slot 3021 and the spacing AC satisfying the following:

[0053] In practical applications, the spacing L2 of each U-shaped groove 3021 can be selected according to the thickness and hardness of the adhesive strip 4. It needs to provide sufficient support without damaging the adhesive strip 4 or hindering the smoothness of the adhesive strip 4's path during sewing.

[0054] like Figure 2 As shown, the width W1 of the fixing groove 2 is slightly larger than the thickness of the adhesive strip 4, such as 0.1mm, 0.11mm, 0.15mm, 0.2mm, 0.22mm, 0.25mm, 0.3mm, 0.33mm, 0.35mm, 0.4mm, 0.44mm, 0.45mm, or 0.5mm, to ensure that the adhesive strip 4 can pass smoothly without lateral displacement. The length L1 of the fixing groove 2 is slightly larger than the width of the adhesive strip 4, such as 0.1mm, 0.11mm, 0.15mm, 0.2mm, 0.22mm, 0.25mm, 0.3mm, 0.33mm, 0.35mm, 0.4mm, 0.44mm, 0.45mm, or 0.5mm, to ensure that the adhesive strip 4 can pass freely without obstruction, while also preventing excessive gaps that could cause the adhesive strip 4 to twist or deform during passage.

[0055] The fixed through groove 2 and / or guide mechanism 3 can be directly fixed to the pressure foot body 1 by welding. After prolonged use, the fixed through groove 2 and / or guide mechanism 3 may wear or deform. To extend the service life of the device, the fixed through groove 2 and / or guide mechanism 3 can also be detachably connected to the pressure foot body 1, such as by screws. This allows for regular inspection of the condition of the fixed through groove 2 and / or guide mechanism 3. If necessary, the old fixed through groove 2 and / or guide mechanism 3 can be replaced, or a suitable fixed through groove 2 and / or guide mechanism 3 can be replaced according to the width of the rubber strip 4, friction, etc., to ensure that the pressure foot device always provides optimal tension control. Replacement is simple: just remove the fixing screws, take out the old fixed through groove 2 and / or guide mechanism 3, and install the new one. The detachable connection also facilitates cleaning of the fixed through groove 2 and / or guide mechanism 3, ensuring the device always maintains good working condition.

[0056] Example 2

[0057] In this embodiment, everything is the same as in embodiment 1, except that the width W2 of each U-shaped placement slot 3021 is equal and the spacing L2 of each U-shaped placement slot 3021 is also equal.

[0058] This embodiment provides a frictional force analysis under these parameter conditions, including the coefficient of kinetic friction, cumulative tension effect, and geometric constraints:

[0059] like Figure 5As shown, each U-shaped groove 3021 includes two parallel crossbars 30211 and a connecting arc 30212 connecting one end of the crossbars 30211. When the rubber strip 4 alternately passes through every two adjacent crossbars 30211, forming an alternating path, and is pulled uniformly, one end of the rubber strip 4 is a free end. Theoretically, the tension at this free end T0→0, but in reality, a very small tension T0>0 is needed to overcome the initial friction. If the movement is uniform when being pulled, the coefficient of kinetic friction applies. The total tension change accumulates with the friction of each crossbar 30211, but the friction at each crossbar 30211 leads to an exponential increase in tension.

[0060] The physical model should be as follows: One end of the rubber strip 4 is subjected to a uniform tension T. Although the other end is not fixed, during the pulling process, the rubber strip 4 is pulled out from the free end. Therefore, a certain tension is required at the free end to initiate the movement. Let the tension at the free end be T0, the number of times it passes through the crossbar 30211 be n, and the coefficient of kinetic friction be μ. k The radius of the bend in each horizontal bar is θ.

[0061] According to Euler's formula, the tension relationship is:

[0062] Total friction (i.e., energy consumed / resistance that the pulling force needs to overcome):

[0063] Minimum starting tension (enabling the pulling action of the rubber strip 4): If a small tension T0 actually exists at the free end (such as air resistance or friction between rope segments), then the uniformly applied tension T must satisfy the following: In practical applications, it is necessary to pre-tighten or restrict the displacement of the free end to ensure that T0 > 0.

[0064] Dynamic characteristic analysis:

[0065] Power transfer: At speed V, the frictional power loss is:

[0066] Example 3:

[0067] This embodiment provides a sewing machine, including a presser foot device as described in Embodiment 1 or 2.

[0068] When the sewing machine starts working, the adhesive strip 4 remains flat and smooth under the action of the presser foot device, effectively preventing problems such as wrinkling, folding, or twisting. The use of this presser foot device also significantly improves the efficiency and quality of sewing the adhesive strip 4.

[0069] The above description of the embodiments is provided to enable those skilled in the art to understand and use the utility model. It will be apparent to those skilled in the art that various modifications can be easily made to these embodiments, and the general principles described herein can be applied to other embodiments without inventive effort. Therefore, the present utility model is not limited to the above embodiments, and any improvements and modifications made by those skilled in the art based on the disclosure of the present utility model without departing from its scope should be within the protection scope of the present utility model.

Claims

1. A presser foot device, characterized in that, It includes a pressure-pressing body (1), a guide mechanism (3) connected to the pressure-pressing body (1) and used for the sequential passage of the adhesive strip (4), and a fixing groove (2). The presser foot body (1) includes a main support (101) connected to the sewing machine, a presser foot plate (103) with a recessed through groove, and a support arm (102) connecting the main support (101) and the presser foot plate (103). The guide mechanism (3) includes an extension (301) and a bend (302). The extension (301) is connected to the support arm (102). The bend (302) is located obliquely above the inlet end of the fixed through groove (2) and is used for the rubber strip (4) to pass through. The fixed through groove (2) is provided at the pressure foot plate (103), and its opening direction is consistent with the opening direction of the recessed through groove on the pressure foot plate (103).

2. The presser foot device according to claim 1, characterized in that, The angle between the bent portion (302) and the vertical direction is 30° to 50°.

3. The presser foot device according to claim 1, characterized in that, An angle adjuster is provided between the extension (301) and the bend (302) for adjusting the angle between the bend (302) and the vertical direction.

4. The presser foot device according to claim 1, characterized in that, The bend (302) consists of several U-shaped placement grooves (3021) connected end to end, which can accommodate the passage of the rubber strip.

5. The presser foot device according to claim 4, characterized in that, The U-shaped placement groove (3021) includes two parallel crossbars (30211) and a connecting arc (30212) connecting the crossbars (30211), wherein the length of the crossbars (30211) is greater than the width of the adhesive strip (4).

6. The presser foot device according to claim 5, characterized in that, The relationship between the length DD' of the crossbar (30211) and the distance AC between two adjacent crossbars (30211) satisfies: Where BB' is the perpendicular distance between the two farthest points on the two connecting arcs (30212), and R is the radius of the connecting arc (30212).

7. The presser foot device according to claim 6, characterized in that, The spacing between two adjacent crossbars (30211) in the bend (302) is consistent, and the length of each crossbar (30211) is also consistent.

8. The presser foot device according to claim 4, characterized in that, The U-shaped placement slot (3021) is provided in at least two.

9. The presser foot device according to claim 1, characterized in that, The width of the fixing groove (2) is 0.1 mm to 0.5 mm greater than the thickness of the adhesive strip (4), and the length of the fixing groove (2) is 0.1 mm to 0.5 mm greater than the width of the adhesive strip (4).

10. A sewing machine, characterized in that, Includes the presser foot device as described in any one of claims 1 to 9.

Images