A sewing machine needle seat with the function of detecting and preventing loose needles

Abstract

The present invention relates to a sewing machine needle seat with the function of detecting and preventing loose needles, which is applied to the field of sewing. By setting a fixed needle plate in contact with the end of the machine needle, when the machine needle is loose, the machine needle transmits the extrusion force exerted by the sewing material to the fixed needle plate. On the one hand, the fixed needle plate transmits the extrusion force to the pull rope in a straightened state, and the pull rope triggers the tension sensor to cause data change, thereby generating a looseness alarm. On the other hand, the straightened pull rope has a limiting effect on the fixed needle plate, which successfully overcomes the extrusion force exerted by the sewing material on the machine needle, thereby allowing the loosened machine needle to smoothly penetrate the sewing material and continue sewing, thereby reducing the problem of poor sewing quality caused by the upward movement of the machine needle. In addition, through the limiting effect of the combination of the bottom frame and the fixed needle plate on the end of the machine needle, the machine needle is not easy to move downward due to the friction of the sewing material, further providing stability for the loosened machine needle, and providing buffer time for personnel to discover the looseness of the machine needle and perform other processing operations such as closing the machine head.

Description

Technical Field

[0001] The invention relates to a sewing machine needle seat, in particular to a sewing machine needle seat which is applied in the sewing field and has the function of detecting and preventing loose needles. Background Art

[0002] A sewing machine is a machine that uses one or more sewing threads to form one or more stitches on the sewing material, so that one or more layers of sewing materials are interwoven or sewn together. Generally, a sewing machine consists of four parts: a machine head, a machine base, a transmission and accessories. The machine head is generally equipped with a needle base to fix the machine needle.

[0003] For example, the specification of Chinese patent CN201810025380.2 discloses a sewing machine cylinder needle seat, which drives the transmission block to move up and down through the flywheel of the sewing machine head, so that the sewing machine cylinder needle seat can move up and down as a whole to achieve sewing. When the pocket is sewn, air is added to the first air inlet and air is discharged from the second air inlet. Since the cylinder piston has been clamped by the pressing pin of the transmission block and cannot move, the cylinder body is linked to the follower needle rod and lifted upward, so that the lifting height of the sewing machine cylinder needle seat meets the processing of specific thickened products. The cylinder needle seat designed in this way is an independent structure and can be modified to the existing sewing machine head equipment.

[0004] The existing needle seat generally fixes the needle with bolts, but during use, since the needle needs to continuously penetrate the sewing material up and down, when the needle moves downward, it is squeezed with the sewing material to achieve penetration, and when the needle moves upward, the penetration hole on the sewing material will produce friction resistance to the needle. Therefore, after long-term use, the needle on the needle seat is prone to loosening, thereby affecting the sewing quality. Summary of the invention

[0005] In view of the above-mentioned prior art, the technical problem to be solved by the present invention is that the needle on the needle seat is prone to loosening due to continuous upward and downward penetration of the sewing material, thereby affecting the sewing quality.

[0006] In order to solve the above problems, the present invention provides a sewing machine needle seat with the function of detecting and preventing loose needles, comprising a needle seat body fixedly mounted at the lower end of a machine head, an inner cavity is formed inside the needle seat body, a bottom groove for inserting a machine needle is formed on the lower inner wall of the inner cavity, a side groove is formed on the side wall of the bottom groove, a fastening plate is slidably connected inside the side groove, a fastener extending into the inside of the side groove and abutting against the fastening plate is threadedly connected to the side end of the needle seat body, and the side end of the fastening plate abuts against the side end of the machine needle;

[0007] The inner cavity is slidably connected to a fixed needle plate, the upper end of the machine needle is inserted into the lower end of the fixed needle plate, a pair of side ends of the fixed needle plate are fixedly connected to slide plates, a pair of side walls of the inner cavity are provided with slideways communicated with the outside world, a pair of slide plates respectively move through a pair of slideways and extend to the outside world, a pair of side ends of the needle seat body are fixedly connected to a pair of side plates, and the slide plate is located between the pair of side plates, and a rope guide column and a pad located on the lower side of the slide plate are also slidably connected between the pair of side plates, and the rope guide column and the pad plate are connected to the side plates by nuts, and a pull rope is fixedly connected to the lower end of the slide plate, the pull rope passes around the outer end of the rope guide column and is fixedly connected to the sensing end of the tension sensor fixedly connected to the lower end of the machine head.

[0008] As a further supplement to the present application, a pair of vertical holes are opened on the side plate, and the two ends of the rope guide column are respectively slidably connected to the inside of a pair of vertical holes close to the needle seat body, and the two ends of the pad are respectively slidably connected to the inside of a pair of vertical holes far from the needle seat body, and multiple nuts are respectively threadedly connected to the two ends of the rope guide column and the pad and are in close contact with the surface of the side plate.

[0009] As a further supplement to the present application, the connection position between the pull rope and the slide plate is located on the side of the pad away from the needle seat body. After the needle is installed, the pull rope is in a normal straightened state and does not generate tension on the tension sensor. At the same time, the lower end of the slide plate is in contact with the upper end of the pad.

[0010] As another improvement of the present application, the machine needle includes a needle body and an elliptical cylinder head, the elliptical cylinder head is fixedly connected to the non-tip end of the needle body, a cylindrical groove is opened at the lower end of the fixed needle plate, and the elliptical cylinder head is inserted into the inside of the cylindrical groove.

[0011] As another improved supplement of the present application, a bottom frame with a rectangular hole is provided at the lower end of the fixed needle plate, and the rectangular hole is located directly below the cylindrical groove, and a plurality of evenly distributed connecting rods are fixedly connected between the upper end of the bottom frame and the lower end of the fixed needle plate.

[0012] As another improved supplement of the present application, the inner diameter of the cylindrical groove is greater than the long axis length of the elliptical cylinder head, the slot length of the rectangular hole is greater than the long axis length of the elliptical cylinder head, and the slot width of the rectangular hole is less than the long axis length of the elliptical cylinder head and greater than its short axis length.

[0013] As another improvement supplement to the present application, the distance from the upper end of the bottom frame to the inner wall of the cylindrical groove is the same as the vertical length of the elliptical cylinder head. After the needle is installed, the elliptical cylinder head is placed on the upper end of the bottom frame and the end faces of the two are in contact.

[0014] As another improved supplement of the present application, the length of the groove of the bottom groove is greater than the length of the major axis of the elliptical cylinder head, and the width of the groove of the bottom groove is greater than the length of the minor axis of the elliptical cylinder head.

[0015] To summarize, the present application provides a fixed needle plate in contact with the needle end inside the needle seat body. When the needle is loose, the needle transmits the extrusion force applied by the sewing material to the fixed needle plate. On the one hand, the fixed needle plate transmits the extrusion force to the straightened pull rope on the outside of the needle seat body, so that the pull rope triggers the change of tension sensor data, thereby generating a looseness alarm. On the other hand, the straightened pull rope also has a limiting effect on the fixed needle plate, which successfully overcomes the extrusion force applied to the needle by the sewing material, so that the loose needle can smoothly penetrate the sewing material and continue sewing, reducing the problem of poor sewing quality caused by the upward loosening of the needle. In addition, through the limiting effect of the combination of the bottom frame and the fixed needle plate on the elliptical cylindrical head, the needle is not easy to loosen downward due to the friction of the sewing material, further providing stability for the loose needle, and providing buffer time for personnel to discover the looseness of the needle and close the machine head. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a stereogram of the first and second embodiments of the present application;

[0017] Figure 2 It is a partial stereogram of the first and second embodiments of the present application;

[0018] Figure 3 The three-dimensional needle seat body of the first and second embodiments of the present application Figure 1 ;

[0019] Figure 4 The three-dimensional needle seat body of the first and second embodiments of the present application Figure 2 ;

[0020] Figure 5 This is a schematic diagram of the front structure of the needle seat body in the first and second embodiments of the present application. Figure 1 ;

[0021] Figure 6 The side structure of the needle seat body of the first and second embodiments of the present application is shown in FIG. Figure 1 ;

[0022] Figure 7 The side structure of the needle seat body of the first and second embodiments of the present application is shown in FIG. Figure 2 ;

[0023] Figure 8 The side structure of the needle seat body of the first and second embodiments of the present application is shown in FIG. Figure 3 ;

[0024] Fig. 9 The three-dimensional needle plate of the second embodiment of the present application Figure 1 ;

[0025] Fig.10The three-dimensional needle plate of the second embodiment of the present application Figure 2 ;

[0026] Fig.11 This is a three-dimensional diagram of the needle of the second embodiment of the present application during installation;

[0027] Fig.12 This is a schematic diagram of the front structure of the needle seat body of the second embodiment of the present application.

[0028] Description of the numbers in the figure:

[0029] 1 machine base, 2 machine head, 201 tension sensor, 3 needle seat body, 301 inner cavity, 302 bottom groove, 303 side groove, 304 slideway, 4 machine needle, 41 needle body, 42 elliptical column head, 5 fasteners, 6 fastening plate, 7 fixed needle plate, 701 cylindrical groove, 8 slide plate, 9 side plate, 901 vertical hole, 10 rope guide column, 11 pull rope, 12 pad, 13 bottom frame, 1301 rectangular hole, 14 connecting rod. DETAILED DESCRIPTION

[0030] Two implementation modes of the present application are described in detail below with reference to the accompanying drawings.

[0031] The first implementation method:

[0032] The present invention provides a sewing machine needle seat with the function of detecting and preventing loose needles, see Figure 1 , Figure 2 and Figure 3 , including a needle seat body 3 fixedly installed at the lower end of the machine head 2, an inner cavity 301 is opened inside the needle seat body 3, a bottom groove 302 for inserting the machine needle 4 is opened on the lower inner wall of the inner cavity 301, a side groove 303 is opened on the side wall of the bottom groove 302, a fastening plate 6 is slidably connected inside the side groove 303, a fastener 5 extending into the inside of the side groove 303 and abutting against the fastening plate 6 is threadedly connected to the side end of the needle seat body 3, and the side end of the fastening plate 6 abuts against the side end of the machine needle 4. When installing the machine needle 4, the non-tip end of the machine needle 4 is inserted into the bottom groove 302 upwards, and then the fastener 5 is tightened to push the fastening plate 6 to abut against the side end of the machine needle 4 to fix the machine needle 4 on the needle seat body 3. Figure 5 As shown, this is the existing method of fixing the needle 4.

[0033] See also Figure 3 and Figure 4The inner cavity 301 is slidably connected with a fixed needle plate 7, and the upper end of the machine needle 4 is inserted into the lower end of the fixed needle plate 7. A pair of side ends of the fixed needle plate 7 are fixedly connected with a slide plate 8. A pair of side walls of the inner cavity 301 are provided with a slideway 304 communicating with the outside world. A pair of slide plates 8 respectively move through a pair of slideways 304 and extend to the outside world. A pair of side ends of the needle seat body 3 are fixedly connected with a pair of side plates 9, and the slide plate 8 is located between the pair of side plates 9. A guide rope column 10 and a pad 12 located at the lower side of the slide plate 8 are also slidably connected between the pair of side plates 9, and the guide rope column 10 and the pad 12 are both connected to the side plates 9 by nuts. A pull rope 11 is fixedly connected to the lower end of the slide plate 8. The pull rope 11 bypasses the outer end of the guide rope column 10 and is fixedly connected to the sensing end of the tension sensor 201 fixedly connected to the lower end of the machine head 2. A controller electrically connected to the tension sensor 201 is installed on the machine base 1, and the tension sensor 201 transmits the sensed tension data to the controller in real time.

[0034] See also Figure 4 The connection position between the pull rope 11 and the slide plate 8 is located on the side of the pad 12 away from the needle seat body 3, so that the up and down movement of the pad 12 is not easy to interfere with the pull rope 11. After the needle 4 is installed, the pull rope 11 is in a normal straightened state and does not generate tension on the tension sensor 201. At the same time, the lower end of the slide plate 8 contacts the upper end of the pad 12. A pair of vertical holes 901 are opened on the side plate 9. The two ends of the rope guide column 10 are respectively slidably connected to the inside of a pair of vertical holes 901 close to the needle seat body 3, and the two ends of the pad 12 are respectively slidably connected to the inside of a pair of vertical holes 901 far from the needle seat body 3. A plurality of nuts are respectively threadedly connected to the two ends of the rope guide column 10 and the pad 12 and are in close contact with the surface of the side plate 9. The rope guide column 10 and the pad 12 are fixed to appropriate positions on a pair of side plates 9 by nuts, so that the pad 12 supports the slide plate 8, and the rope guide column 10 straightens the pull rope 11.

[0035] Loose needle 4 detection method: please refer to Figure 5 and Figure 6When in use, the needle 4 penetrates downward through the sewing material and will be subjected to the reverse squeezing force of the sewing material on the needle 4. When the needle 4 is not loose, the fixing of the needle 4 by the fastening plate 6 allows the needle 4 to overcome the squeezing force and perform sewing. When the needle 4 is loose to a certain extent, the reverse squeezing force of the sewing material will cause the loose needle 4 to tend to move upward. At this time, the needle 4 applies an upward thrust to the fixed needle plate 7, which in turn causes the slide plate 8 to generate an upward pulling force on the pull rope 11, and the pull rope 11 generates a pulling force on the tension sensor 201. The data sensed by the sensor 201 changes significantly, and the controller issues a looseness warning after receiving the data change. In addition, since the pull rope 11 is in a straightened state, although it transmits the tension of the slide plate 8 to the tension sensor 201, it also limits the slide plate 8, making it difficult for the fixed needle plate 7 and the slide plate 8 to move upward, successfully overcoming the thrust of the needle 4, and then allowing the loose needle 4 to smoothly penetrate the sewing material and continue sewing, reducing the problem of poor sewing quality caused by the loose needle 4.

[0036] Adjustable installation process of needle 4: please refer to Figure 7 1. Insert the non-tip end of the needle 4 upward into the bottom groove 302 and abut against the fixed needle plate 7. Then, according to the sewing needs, adjust the insertion depth of the needle 4 to keep a suitable distance between the tip of the needle 4 and the machine base 1, so as to facilitate sewing the sewing material. During the process of adjusting the position of the needle 4 up and down, the fixed needle plate 7 will move up and down in the inner cavity 301 with the needle 4, and keep in contact with the upper end of the needle 4 under the action of its own weight;

[0037] 2. After the position of the needle 4 is confirmed, first tighten the fastener 5 to fix the position of the needle 4, and then Figure 4 and Figure 8 As shown, the pad 12 is moved along the vertical hole 901 to the lower side of the slide plate 8 and contacts the slide plate 8. The position of the pad 12 is fixed by a nut, and the pad 12 is moved downward along the vertical hole 901 until it contacts the pull rope 11 and straightens it. In this way, when the loose needle 4 generates a thrust on the fixed needle plate 7, the pull rope 11 can transmit the force to the tension sensor 201 in a timely and effective manner.

[0038] Second implementation method:

[0039] This embodiment is based on the embodiment 1, and a bottom frame 13 and its related structures are added, and the structure of the needle 4 is specifically set: please refer to Fig. 9 , Fig.10 and Fig.11The machine needle 4 includes a needle body 41 and an elliptical cylindrical head 42, the elliptical cylindrical head 42 is fixedly connected to the non-tip end of the needle body 41, a cylindrical groove 701 is opened at the lower end of the fixed needle plate 7, the elliptical cylindrical head 42 is inserted into the inside of the cylindrical groove 701, and a bottom frame 13 with a rectangular hole 1301 is provided at the lower end of the fixed needle plate 7, and the rectangular hole 1301 is located directly below the cylindrical groove 701, and a plurality of evenly distributed connecting rods 14 are fixedly connected between the upper end of the bottom frame 13 and the lower end of the fixed needle plate 7.

[0040] The inner diameter of the cylindrical groove 701 is larger than the long axis length of the elliptical cylinder head 42, so that the elliptical cylinder head 42 can rotate smoothly in the cylindrical groove 701, the slot length of the rectangular hole 1301 is larger than the long axis length of the elliptical cylinder head 42, and the slot width of the rectangular hole 1301 is smaller than the long axis length of the elliptical cylinder head 42 and larger than its short axis length. Fig.11 As shown, when the length direction of the elliptical cylinder head 42 is consistent with the length direction of the slot of the rectangular hole 1301, the elliptical cylinder head 42 can smoothly pass through the rectangular hole 1301 and enter the cylindrical groove 701, and then the machine needle 4 is rotated 90° to make the length direction of the elliptical cylinder head 42 consistent with the width direction of 1031. In this way, the elliptical cylinder head 42 can be restricted at the upper end of the bottom frame 13, making it difficult to pull downward, thereby realizing a stable connection between the machine needle 4 and the fixed needle plate 7 and the bottom frame 13.

[0041] Combination Fig.12 As shown, the distance from the upper end of the bottom frame 13 to the upper inner wall of the cylindrical groove 701 is the same as the vertical length of the elliptical column head 42. In this way, after the needle 4 is installed, the elliptical column head 42 is placed on the upper end of the bottom frame 13, and the upper and lower end surfaces of the elliptical column head 42 are in contact with the upper inner wall of the cylindrical groove 701 and the upper end surface of the bottom frame 13 respectively.

[0042] The length of the slot of the bottom groove 302 is greater than the long axis length of the elliptical cylinder head 42, and the width of the slot of the bottom groove 302 is greater than the short axis length of the elliptical cylinder head 42. This makes it convenient to insert the elliptical cylinder head 42 into the bottom groove 302 and smoothly pass through the rectangular hole 1301 into the cylindrical groove 701. At this time, the machine needle 4 is rotated 90° to achieve the connection and positioning of the machine needle 4 and the fixed needle plate 7.

[0043] Through the above arrangement, this embodiment not only satisfies the looseness detection of the needle 4 and the restriction of the upward movement of the needle 4 in the embodiment 1, but also has the function of restricting the downward movement of the needle 4, further reducing the problem of poor sewing quality caused by the looseness of the needle 4, as follows:

[0044] See also Fig.12When the loose needle 4 moves out of the sewing material, it will be affected by the downward friction force exerted by the sewing material, so that the loose needle 4 has a tendency to move downward. At this time, due to the supporting effect of the bottom frame 13 on the elliptical cylinder head 42, the pad 12 has a supporting effect on the slide plate 8, so that the fixed needle plate 7 can remain stable and overcome the friction force exerted on the needle 4. In addition, the upward direction of the slide plate 8 is restricted by the pull rope 11, so that the positions of the fixed needle plate 7 and the slide plate 8 remain stable, thereby making the loose needle 4 temporarily continue to remain stable, which is not easy to affect the sewing quality, and provides buffer time for personnel to discover the looseness of the needle 4 and close the machine head 2.

[0045] In view of current practical needs, the above-mentioned implementation mode adopted in this application is not limited to the scope of protection. Various changes made within the knowledge scope of technical personnel in this field without departing from the concept of this application still fall within the scope of protection of the present invention.

Claims

1. A sewing machine needle holder with the function of detecting and preventing loose needles, comprising a needle holder body (3) fixedly mounted at the lower end of a machine head (2), characterized in that: The needle seat body (3) has an inner cavity (301) formed therein, the lower inner wall of the inner cavity (301) has a bottom groove (302) for inserting the machine needle (4), the side wall of the bottom groove (302) has a side groove (303), the inside of the side groove (303) is slidably connected with a fastening plate (6), the side end of the needle seat body (3) is threadedly connected with a fastener (5) extending into the inside of the side groove (303) and abutting against the fastening plate (6), and the side end of the fastening plate (6) abuts against the side end of the machine needle (4); The inner cavity (301) is slidably connected to a fixed needle plate (7), the upper end of the needle (4) is plugged into the lower end of the fixed needle plate (7), a pair of side ends of the fixed needle plate (7) are fixedly connected to a slide plate (8), a pair of side walls of the inner cavity (301) are provided with a slideway (304) communicating with the outside, a pair of slide plates (8) are respectively movable through a pair of slideways (304) and extend to the outside, a pair of side ends of the needle seat body (3) are fixedly connected to a pair of side plates (9), and the slide plates (8) are slidably connected to the inner cavity (301) and the upper end of the needle seat body (3) is fixedly connected to a pair of side plates (9). The plate (8) is located between a pair of side plates (9), and a guide rope column (10) and a pad (12) located at the lower side of the slide plate (8) are also slidably connected between the pair of side plates (9), and the guide rope column (10) and the pad (12) are both connected to the side plates (9) via nuts, and a pull rope (11) is fixedly connected to the lower end of the slide plate (8), and the pull rope (11) passes around the outer end of the guide rope column (10) and is fixedly connected to the sensing end of a tension sensor (201) fixedly connected to the lower end of the machine head (2); A pair of vertical holes (901) are formed on the side plate (9), and the two ends of the rope guide column (10) are respectively slidably connected to the inside of the pair of vertical holes (901) close to the needle seat body (3), and the two ends of the pad (12) are respectively slidably connected to the inside of the pair of vertical holes (901) far from the needle seat body (3), and the plurality of nuts are respectively threadedly connected to the two ends of the rope guide column (10) and the pad (12) and are in close contact with the surface of the side plate (9); The connection position between the pull rope (11) and the slide plate (8) is located on the side of the pad (12) away from the needle seat body (3). After the needle (4) is installed, the pull rope (11) is in a normal straightened state and does not generate tension on the tension sensor (201). At the same time, the lower end of the slide plate (8) is in contact with the upper end of the pad (12).

2. A sewing machine needle holder with the function of detecting and preventing loose needles according to claim 1, characterized in that: The machine needle (4) comprises a needle body (41) and an elliptical cylindrical head (42), wherein the elliptical cylindrical head (42) is fixedly connected to the non-tip end of the needle body (41), and a cylindrical groove (701) is formed at the lower end of the needle fixing plate (7), and the elliptical cylindrical head (42) is inserted into the cylindrical groove (701).

3. The sewing machine needle holder with the function of detecting and preventing loose needles according to claim 2, characterized in that: A bottom frame (13) with a rectangular hole (1301) is provided at the lower end of the needle fixing plate (7), and the rectangular hole (1301) is located directly below the columnar groove (701). A plurality of evenly distributed connecting rods (14) are fixedly connected between the upper end of the bottom frame (13) and the lower end of the needle fixing plate (7).

4. The sewing machine needle holder with the function of detecting and preventing loose needles according to claim 3, characterized in that: The inner diameter of the columnar groove (701) is greater than the length of the major axis of the elliptical column head (42), the notch length of the rectangular hole (1301) is greater than the length of the major axis of the elliptical column head (42), and the notch width of the rectangular hole (1301) is less than the length of the major axis of the elliptical column head (42) and greater than the length of its minor axis.

5. The sewing machine needle holder with the function of detecting and preventing loose needles according to claim 3, characterized in that: The distance from the upper end of the bottom frame (13) to the upper inner wall of the cylindrical groove (701) is the same as the vertical length of the elliptical column head (42). After the needle (4) is installed, the elliptical column head (42) is placed on the upper end of the bottom frame (13) and the end surfaces of the two are in contact.

6. The sewing machine needle holder with the function of detecting and preventing loose needles according to claim 2, characterized in that: The notch length of the bottom groove (302) is greater than the major axis length of the elliptical column head (42), and the notch width of the bottom groove (302) is greater than the minor axis length of the elliptical column head (42).

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