Cam follower presser foot mechanism

Abstract

The utility model relates to clothing machinery technical field, concretely is a cam type follow-up presser foot mechanism, including the needle bar of flat car, follow-up rod, needle bar is with follow-up rod respectively fixed drive seat, follow-up seat, drive swing board lower end articulates drive seat, upper end articulates the cam extension arm of "b" shape follow-up cam of cam, follow-up cam middle part articulates flat car head, driven piece middle part articulates the head, left end cooperation follow-up cam cam body, right end articulates follow-up seat, follow-up rod lower end fixedly set pattern machine presser foot, and the presser foot mouth is tubular and is set in the needle outside. Compared with prior art, the utility model effectively solved the core problem that traditional presser foot and needle movement disjointed, and the stability of pressing and pressure adaptability are more optimal, and the operation convenience and structural reliability are stronger.

Description

Technical Field

[0001] This utility model relates to the field of garment machinery technology, specifically a cam-type follow-up presser foot mechanism. Background Technology

[0002] In industrialized garment production, the presser foot of a flatbed sewing machine is a core component for pressing fabric and assisting in feeding. Its coordination with the needle's movement directly affects sewing quality and production efficiency. Currently, most mainstream flatbed sewing machine presser feet employ independent lifting control schemes, typically such as pedal-mechanical linkage or spring-preloaded fixed pressure designs. Their movement is completely disconnected from the reciprocating piercing motion of the needle, failing to achieve real-time dynamic coordination. This exposes several technical pain points in practical applications: First, there is a lack of coordinated pressure during the piercing stage. When the needle penetrates the fabric, the traditional presser foot cannot synchronize with the piercing rhythm, causing the fabric to lose effective support the moment it enters the fabric, making it prone to local slippage or elastic rebound. When sewing low-friction fabrics, slippage directly causes stitch wrinkling and needle hole misalignment; when processing thick materials, the piercing force of the needle can easily push up the upper layer of fabric, creating gaps between fabric layers, making it impossible for the stitches to fully engage the layers, ultimately leading to easy seam cracking and insufficient stitch strength, making it difficult to meet the basic usage requirements of clothing.

[0003] Secondly, there is a delay in pressure release during the feeding stage. After the needle completes piercing and lifts, the traditional presser foot needs to be triggered by an independent control mechanism, resulting in a response delay. At this time, the feed teeth have already pushed the fabric forward, while the presser foot remains in a pressed state. The frictional resistance between the two will drag the fabric. When sewing elastic fabrics, the resistance can easily cause the fabric to be overstretched and deformed after sewing. When sewing multiple layers together, the difference in the coefficient of friction of different fabrics will exacerbate the uneven feeding speed, resulting in a "fabric-eating" phenomenon, causing height differences and wrinkles at the seams, requiring subsequent manual finishing, which significantly reduces production efficiency.

[0004] Third, the pressure adjustment lacks adaptability to different scenarios. Traditional presser foot pressure needs to be preset manually and remains fixed after adjustment, making it impossible to dynamically switch according to the needle movement stage. If the presser foot maintains high pressure during the feeding stage, it will increase the frictional resistance between the fabric and the presser foot, hindering the smooth feeding of the fabric and easily causing snags and holes in thin fabrics. If the pressure is insufficient during the piercing and fixing stage, it cannot effectively restrain the fabric displacement, and problems such as skewed stitches and fabric arching are prone to occur frequently during mass production. This results in poor product quality stability, high rework rates, and increased production costs for enterprises.

[0005] The key to the above problems lies in the lack of a motion coordination mechanism between the traditional presser foot and the needle, which makes it unable to adapt to the dynamic needs of different fabrics and sewing processes. This has become a major bottleneck restricting the improvement of sewing accuracy and efficiency of flatbed sewing machines. Utility Model Content

[0006] To overcome the defects or one of the defects of the existing technology, this utility model provides a cam-type follower presser foot mechanism, and the technical solution adopted is as follows: A cam-type follower presser foot mechanism includes a needle bar that is slidably disposed within the head of a flatbed car and can reciprocate up and down. Unlike existing technologies, it also includes... The follower rod is slidably set inside the head of the flatbed car, with its axis parallel to the axis of the needle bar; The drive seat and the follower seat are fixed on the needle bar and the follower rod, respectively; The drive swing plate is hinged at its lower end to the drive base; The follower cam is shaped like a "b" and includes a cam body and a cam extension arm that extends to the right at the upper end. The free end of the cam extension arm is hinged to the upper end of the drive swing plate, and the middle part of the cam body is directly or indirectly hinged to the flatcar head. The driven member is directly or indirectly hinged to the head of the flatcar in the middle, hinged to the follower seat on the right, and engaged with the cam body on the left. The presser foot of the pattern sewing machine includes a presser foot handle and a presser foot nozzle. The presser foot handle is fixed to the lower end of the follower rod, and the presser foot nozzle is tubular and sleeved on the outside of the needle of the flatbed sewing machine.

[0007] Furthermore, a roller is mounted on the left end of the driven member, and the roller rolls in cooperation with the cam body.

[0008] Furthermore, the roller is a ball bearing.

[0009] Furthermore, it also includes a presser foot lifting plate and a presser foot lifting cylinder; the presser foot lifting cylinder is fixed to the flatbed sewing machine body; the middle part of the presser foot lifting plate is hinged to the flatbed sewing machine body, its lower end abuts against the cylinder rod of the presser foot lifting cylinder, and its upper end is fixed to a linkage pin; the linkage pin is a component of the sewing machine with a built-in presser foot lifting device, and rotating the linkage pin can independently realize the lifting and lowering of the pattern machine presser foot; after the linkage pin passes through the flatbed sewing machine body, it is fixed to a linkage plate, and the linkage plate is hinged to the cam extension arm; when the needle stops working, it automatically stops at the upper needle position. At this time, the cylinder of the lifting presser foot extends and presses against the lower end of the lifting presser foot plate, which in turn drives the linkage pin, linkage plate, and cam extension arm to swing in sequence. This drives the follower cam, follower, follower seat, and follower rod to move upward synchronously, so that the presser foot of the pattern making machine is raised and the roller is disengaged from the cam body. When the presser foot of the pattern making machine is lowered, the roller and cam body resume contact. The large-amplitude up-and-down movement of the needle bar is transformed into a small-amplitude up-and-down movement of the follower rod through the cooperation of the follower cam and follower, so that the presser foot of the pattern making machine follows the needle.

[0010] Furthermore, it also includes a blower pipe fixed on the flatbed machine body. One end of the blower pipe is provided with an air source interface, and the other end is a flat blower nozzle. The air source interface is used to connect to an external compressed air source. The distance between the central axis of the blower nozzle and the lower edge of the presser foot nozzle when it descends to the lowest point is 5-15mm, and the air outlet direction of the blower nozzle is directly facing the fabric area below the needle and presser foot nozzle.

[0011] Compared with existing technologies, this utility model uses a linkage structure of a "b"-shaped follower cam, a drive swing plate, and a driven component, combined with the rolling cooperation of rollers and the cam body, to allow the presser foot to accurately follow the dynamic movement of the needle. This effectively solves the problem of the traditional presser foot and needle movement becoming disconnected, reducing defects such as loose stitches, skipped stitches, fabric "biting," and wrinkles, while balancing sewing quality and efficiency. The newly added air tube can accurately blow up the upper thread on the needle, preventing it from being pressed down and pulled out, thus improving stitch neatness. At the same time, the cooperation between the presser foot lifting cylinder and the linkage component enables one-button lifting of the presser foot and automatic needle stop at the upper needle position. Moreover, the linkage pin reuses a component that is already on the sewing machine, eliminating the need for major modifications to the flatbed sewing machine. This makes the operation convenient, the maintenance cost low, the transmission stable, and it is suitable for industrial-grade continuous operation requirements. Attached Figure Description

[0012] Figure 1 This is a schematic diagram of the structure of the present invention and the flatbed cart.

[0013] Figure 2 for Figure 1 A magnified view of a portion of point A in the middle.

[0014] Figure 3 for Figure 1 A magnified view of a section at point B in the middle.

[0015] Figure 4 This is a structural schematic diagram of the present invention and the flatbed cart from another perspective.

[0016] Figure 5 for Figure 4 A magnified view of a section at point C. Detailed Implementation

[0017] The present invention will be further described below with reference to the accompanying drawings.

[0018] like Figure 1-5 The cam-type follower presser foot mechanism 200 shown includes A needle bar 101 is slidably set inside the head of the flatbed 100 and can move up and down reciprocally; The follower rod 201 is slidably disposed inside the head of the flatbed 100, and its axis is parallel to the axis of the needle bar 101; The drive seat 202 and the follower seat 203 are fixed on the needle bar 101 and the follower bar 201, respectively; The drive swing plate 204 is hinged at its lower end to the drive base 202; The follower cam 205 is in the shape of "b" and includes a cam body 2051 and a cam extension arm 2052 extending to the right at the upper end. The free end of the cam extension arm 2052 is hinged to the upper end of the drive swing plate 204, and the middle part of the cam body 2051 is directly or indirectly hinged to the head of the flat car 100. The follower 206 is directly or indirectly hinged to the head of the flatcar 100 in the middle, hinged to the follower seat 203 on the right end, and engaged with the cam body 2051 on the left end. The presser foot 207 of the pattern making machine includes a presser foot handle 2071 and a presser foot nozzle 2072. The presser foot handle 2071 is fixed to the lower end of the follower rod 201, and the presser foot nozzle 2072 is tubular and sleeved on the needle 102 of the flatbed 100.

[0019] The working principle of this embodiment is as follows: When the flatbed sewing machine is in operation, the needle bar 101 reciprocates up and down along the head of the flatbed sewing machine 100, and the drive seat 202 fixed on the needle bar 101 moves up and down synchronously with the needle bar 101. Since the lower end of the drive swing plate 204 is hinged on the drive seat 202, the up and down movement of the drive seat 202 will cause the drive swing plate 204 to swing around the hinge point between it and the drive seat 202.

[0020] The upper end of the drive swing plate 204 is hinged to the free end of the cam extension arm 2052 of the follower cam 205. The swing of the drive swing plate 204 will pull or push the cam extension arm 2052, so that the follower cam 205 swings synchronously around the hinge point between its middle part and the head of the flat car 100.

[0021] The follower 206 is hinged at the middle to the head of the flatbed 100, and its left end engages with the cam body 2051 of the follower cam 205. When the follower cam 205 swings, the contour of the cam body 2051 drives the follower 206 to swing around its central hinge point. The right end of the follower 206 is hinged to the follower seat 203, which is fixed on the follower rod 201. The follower rod 201 is slidably disposed inside the head of the flatbed 100, with its axis parallel to the needle bar 101. Therefore, the swing of the follower 206 is converted into the up-and-down movement of the follower seat 203, which in turn drives the follower rod 201 to slide up and down along the head of the flatbed 100.

[0022] The presser foot handle 2071 of the pattern sewing machine presser foot 207 is fixed at the lower end of the follower rod 201. When the follower rod 201 slides up and down, it will drive the presser foot handle 2071 and the presser foot nozzle 2072 integrated with the presser foot handle 2071 to move up and down synchronously. The presser foot nozzle 2072 is sleeved outside the needle 102 of the flatbed 100, so as to realize the follow-up effect of the presser foot nozzle 2072 and the presser foot handle 2071 following the movement of the needle 102.

[0023] In another preferred embodiment, a roller 208 is mounted on the left end of the follower 206, and the roller 208 rolls with the cam body 2051. By converting the sliding engagement between the follower 206 and the cam body 2051 into a rolling engagement through the roller 208, the frictional resistance and wear during their relative movement can be significantly reduced. This ensures that the follower cam 205 can stably drive the follower 206 during its oscillation, avoiding transmission jamming or premature component wear caused by excessive sliding friction, and ensuring the continuity and stability of the entire presser foot mechanism's follower movement.

[0024] In another preferred embodiment, the roller 208 is a ball bearing. Utilizing the high precision and low rotational resistance of the ball bearing, the rolling transmission effect between the roller 208 and the cam body 2051 can be further optimized, reducing energy loss and vibration during transmission. Even under high-frequency sewing conditions on a flatbed sewing machine, the roller 208 can accurately follow the contour of the cam body 2051, avoiding lag in the movement of the follower 206 due to poor rotation of the roller 208, and further improving the follow-up accuracy of the presser foot mechanism.

[0025] In another preferred embodiment, it further includes a presser foot lifting plate 210 and a presser foot lifting cylinder 211; the presser foot lifting cylinder 211 is fixedly mounted on the body of the flatbed sewing machine 100; the presser foot lifting plate 210 is hinged to the body of the flatbed sewing machine 100 in the middle, its lower end abuts against the cylinder rod of the presser foot lifting cylinder 211, and its upper end is fixedly connected to a linkage pin 209; the linkage pin 209 is a component of the sewing machine with a built-in presser foot lifting device, and rotating the linkage pin 209 can independently realize the lifting and lowering of the pattern machine presser foot 207; the linkage pin 209 passes through the flatbed sewing machine 100 body with a gap and is fixedly connected to a linkage plate, which is hinged to the cam extension arm 2052; when the needle 102 stops working, it automatically stops at the upper needle position, at which time the presser foot is lifted. When the cylinder 211 extends, it presses against the lower end of the presser foot plate 210, which in turn drives the linkage pin 209, linkage plate, and cam extension arm 2052 to swing. This, in turn, drives the follower cam 205, follower 206, follower seat 203, and follower rod 201 to move upward synchronously, causing the pattern machine presser foot 207 to rise and the roller 208 to disengage from the cam body 2051. When the pattern machine presser foot 207 is lowered, the roller 208 resumes contact with the cam body 2051. The large-amplitude reciprocating motion of the needle bar 101 is transformed into a small-amplitude up-and-down motion of the follower rod 201 through the cooperation of the follower cam 205 and follower 206, thus realizing the follow-up action of the pattern machine presser foot 207 with the sewing needle 102. This preferred embodiment reuses the linkage pin that comes with the sewing machine, which can independently control the lifting and lowering of the presser foot of the pattern sewing machine. With the presser foot lifting cylinder and linkage component, the presser foot can be lifted with one button and the needle can be automatically stopped in the upper needle position. When the presser foot is lifted, the roller and the cam body are disengaged to reduce wear. After being lowered, the presser foot can accurately follow the needle. It is easy to operate and does not require major modifications to the flatbed sewing machine.

[0026] In another preferred embodiment, a blower pipe 300 fixed to the body of the flatbed sewing machine 100 is also included. One end of the blower pipe 300 is provided with an air source interface, and the other end is a flat air outlet. The air source interface is used to connect to an external compressed air source. The distance between the central axis of the air outlet and the lower edge of the presser foot nozzle 2072 when it descends to its lowest point is 5-15mm, and the air outlet direction is directly facing the fabric area below the needle 102 and the presser foot nozzle 2072, which is used to blow up the upper thread on the needle 102 to prevent the upper thread from being pressed and pulled out and stretched during processing. In this preferred embodiment, the blower pipe is precisely aligned with the fabric area below the needle and presser foot nozzle through the flat air outlet. After connecting to an external compressed air source, it can blow up the upper thread on the needle, preventing the upper thread from being pressed and pulled out and stretched during processing, effectively improving the neatness of the sewing stitches.

[0027] The above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A cam-type follower presser foot mechanism (200), comprising a needle bar (101) slidably disposed within the head of a flatbed car (100) and capable of reciprocating up and down, characterized in that, Also includes The follower rod (201) is slidably set inside the head of the flat car (100), and its axis is parallel to the axis of the needle bar (101); The drive seat (202) and the follower seat (203) are fixed on the needle bar (101) and the follower rod (201), respectively; The drive plate (204) is hinged at its lower end to the drive base (202); The follower cam (205) is in the shape of "b" and includes a cam body (2051) and a cam extension arm (2052) extending to the right at the upper end. The free end of the cam extension arm (2052) is hinged to the upper end of the drive swing plate (204), and the middle part of the cam body (2051) is directly or indirectly hinged to the head of the flatcar (100). The follower (206) is directly or indirectly hinged to the head of the flatcar (100) in the middle, hinged to the follower seat (203) on the right end, and engaged with the cam body (2051) on the left end; The pattern machine presser foot (207) includes a presser foot handle (2071) and a presser foot nozzle (2072). The presser foot handle (2071) is fixed at the lower end of the follower rod (201), and the presser foot nozzle (2072) is tubular and sleeved on the needle (102) of the flatbed (100).

2. The cam-type follower presser foot mechanism according to claim 1, characterized in that, A roller (208) is mounted on the left end of the follower (206), and the roller (208) rolls in cooperation with the cam body (2051).

3. The cam-type follower presser foot mechanism according to claim 2, characterized in that, The roller (208) is a ball bearing.

4. The cam-type follower presser foot mechanism according to claim 1, characterized in that, It also includes a presser foot lifting plate (210) and a presser foot lifting cylinder (211); the presser foot lifting cylinder (211) is fixed on the body of the flatbed (100); the middle part of the presser foot lifting plate (210) is hinged to the body of the flatbed (100), its lower end abuts against the cylinder rod of the presser foot lifting cylinder (211), and its upper end is fixedly connected to the linkage pin (209); the linkage pin (209) is a component of the sewing machine with a built-in presser foot lifting device, and rotating the linkage pin (209) can independently realize the lifting and lowering of the pattern machine presser foot (207); the linkage pin (209) passes through the gap into the body of the flatbed (100) and is fixedly connected to the linkage plate, and the linkage plate is hinged to the cam extension arm (2052); when the needle (102) stops working, it automatically stops at the upper needle position, at which time the presser foot lifting cylinder (211) extends to the upper needle position. The lower end of the presser foot plate (210) is pressed up, which in turn drives the linkage pin (209), linkage plate, and cam extension arm (2052) to swing in sequence, thereby driving the follower cam (205), follower (206), follower seat (203) and follower rod (201) to move up synchronously, so that the pattern machine presser foot (207) is raised and the roller (208) is disengaged from the cam body (2051); when the pattern machine presser foot (207) is lowered, the roller (208) and cam body (2051) resume contact, and the large-amplitude up-and-down movement of the needle bar (101) is transformed into the small-amplitude up-and-down movement of the follower rod (201) through the cooperation of the follower cam (205) and follower (206), so that the pattern machine presser foot (207) follows the needle (102).

5. The cam-type follower presser foot mechanism according to claim 1, characterized in that, It also includes a blower pipe (300) fixed on the body of the flatbed (100). One end of the blower pipe (300) is provided with an air source interface, and the other end is a flat blower. The air source interface is used to connect to an external compressed air source. The distance between the central axis of the blower and the lower edge of the presser foot nozzle (2072) when it descends to the lowest point is 5-15mm, and the air outlet direction of the blower is directly facing the fabric area below the needle (102) and the presser foot nozzle (2072).

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