Sewing machine cloth thickness detection device and sewing machine

Abstract

The application relates to the technical field of sewing equipment, in particular to a sewing machine cloth thickness detection device and a sewing machine. The sewing machine cloth thickness detection device is installed on a presser bar of the sewing machine and abuts against the rear end of a presser foot plate, and is used for detecting the displacement of the front end of the presser foot plate in the height direction of the sewing machine. The sewing machine cloth thickness detection device comprises a shell which is installed on the presser bar and has a mounting cavity; a detection mechanism which comprises a first detection assembly and a second detection assembly, one end of the first detection assembly is installed in the mounting cavity, the other end of the first detection assembly extends out of the mounting cavity and extends in the height direction of the sewing machine so as to abut against the rear end of the presser foot plate, and the second detection assembly is arranged on the side wall of the mounting cavity opposite to the first detection assembly; wherein the first detection assembly rotates with the rear end of the presser foot plate, and the second detection assembly detects and feeds back the rotation angle of the first detection assembly. In this way, the thickness of the cloth can be detected in advance before the cloth completely enters below the presser foot plate.

Description

Technical Field

[0001] This application relates to the field of sewing equipment technology, and in particular to a sewing machine fabric thickness detection device and a sewing machine. Background Technology

[0002] During the sewing process, sewing machines require adjustments to relevant components to adapt to different fabric thicknesses and sewing techniques. Existing sewing machine fabric thickness detection devices typically consist of a Hall effect sensor and a magnet mounted on the presser foot. The sensor and magnet work together to detect the height of the presser foot's rise, thus determining the fabric thickness.

[0003] However, this structural setup requires the fabric to be fully inside the presser foot plate to obtain an accurate fabric thickness. The state of other components of the sewing machine, such as the presser bar, is generally determined when the fabric is fully inside the presser foot plate. This results in insufficient time to adjust other components to adapt to the sewing process of the corresponding fabric. Furthermore, when the sewing machine teeth move up and down, both the presser foot arm and the presser foot plate will move up and down accordingly. If the detection structure is located only in one of the two, there may be errors in the thickness detection. Utility Model Content

[0004] Therefore, it is necessary to provide a sewing machine fabric thickness detection device and sewing machine that can detect the fabric thickness before it is fully under the presser foot and reduce detection errors.

[0005] To solve the above-mentioned technical problems, this application provides the following technical solution:

[0006] A sewing machine fabric thickness detection device is installed on the presser foot arm of the sewing machine and abuts against the rear end of the presser foot plate in the length direction of the sewing machine, for detecting the displacement of the front end of the presser foot plate in the height direction of the sewing machine. The sewing machine fabric thickness detection device includes:

[0007] The housing is mounted on the presser foot arm and has a mounting cavity;

[0008] The testing mechanism includes a first testing component and a second testing component. One end of the first testing component is installed in the mounting cavity, and the other end extends out of the mounting cavity and extends in the height direction of the sewing machine to abut against the rear end of the presser foot plate. The second testing component is disposed on the side wall of the mounting cavity opposite to the first testing component.

[0009] The first detection component rotates with the rear end of the pressure foot plate, and the second detection component detects and provides feedback on the rotation angle of the first detection component.

[0010] Understandably, this application, by setting a detection mechanism on the presser foot arm and having one end of the first detection component abut against the rear end of the presser foot plate, allows the first detection component to move along the height of the sewing machine when the fabric enters from the front end of the presser foot plate. The other end of the presser foot arm rotates accordingly. A second detection component then detects and reports the rotation angle, allowing the determination of the fabric thickness entering the presser foot plate. Thus, the fabric thickness can be detected as soon as it enters the front end of the presser foot plate, before it is fully below it, enabling early detection of the fabric thickness. This allows for the pre-adjustment of other sewing machine components to the appropriate sewing position or parameters for the fabric. Furthermore, since the two ends of the first detection component are connected to the presser foot arm and presser foot plate respectively, the presser foot arm and presser foot plate move simultaneously when the sewing machine teeth move up and down. This allows the influence of the detection mechanism's movement on the presser foot arm and presser foot plate to cancel each other out, thereby reducing the detection error of the fabric thickness and improving the accuracy of the fabric thickness detection.

[0011] In one embodiment, the first detection component includes a rotating member and a probe rod. The rotating member is rotatably mounted in the mounting cavity and has a through hole in its circumferential direction. One end of the probe rod passes through the through hole, and the other end extends out of the mounting cavity and extends in the height direction of the sewing machine to abut against the rear end of the presser foot plate.

[0012] The probe rod moves with the rear end of the pressure foot plate and drives the rotating component to rotate.

[0013] Understandably, with this setup, the thickness of the fabric can be detected in advance by the second detection component, based on the rotation angle of the rotating component, before the fabric fully enters the presser foot plate.

[0014] In one embodiment, the probe has a first section and a second section connected to each other. The first section has a through hole at the end away from the second section, and the second section is bent at the end away from the first section to form a probe part. The probe part is fixed to the rear end of the pressure foot plate.

[0015] The first segment and the second segment are set at an angle.

[0016] Understandably, the first and second sections of the probe are angled to accommodate the installation of the detection mechanism. This allows the first section to rotate within the housing along with the second section, preventing interference between the first section and the housing due to the installation angle limitation when the second section rotates it. It also increases the structural strength of the probe during motion transmission between the rotating component and the pressure foot plate, preventing bending and damage under stress. Simultaneously, the second section is bent to form the detection part, increasing the contact area between the probe and the pressure foot plate, preventing damage due to insufficient contact area when the pressure foot plate moves.

[0017] In one embodiment, the first detection component further includes an elastic element disposed in the mounting cavity, with one end fixed to the cavity wall of the mounting cavity and the other end connected in a compressed manner to one end of the probe rod passing through the through hole.

[0018] Understandably, the elastic element provides a force that tightly abuts the rear end of the presser foot plate to the probe, ensuring that the probe remains in contact with the rear end of the presser foot plate and moves with it. This also improves the stability of the probe's movement and prevents overshooting or shaking of the probe when the rear end of the presser foot plate begins to move or during its movement, which could affect the fabric detection results.

[0019] In one embodiment, the second detection component includes a circuit board and an angle detector. The circuit board is disposed on one side wall of the mounting cavity, and the angle detector is disposed relative to the rotating component and connected to the circuit board.

[0020] The angle detector detects the rotation angle of the rotating component, and the circuit board receives and feeds back the rotation angle.

[0021] In one embodiment, the sewing machine fabric thickness detection device further includes an electrical control unit connected to the circuit board, which is used to obtain the rotation angle fed back by the circuit board and convert the rotation angle into a height change value.

[0022] Understandably, this setup improves the intuitiveness of the fabric thickness detection results and enhances the intelligence and user experience of the sewing machine's fabric thickness detection device.

[0023] In one embodiment, the angle detector is a magnetic sensor, and a magnet is mounted on the rotating component, with the central axis of the magnetic sensor coinciding with the central axis of the magnet.

[0024] The magnet rotates with the rotating component, and the magnetic sensor detects the rotation angle of the magnet.

[0025] In one embodiment, a limiting hole is provided at the central axis of the rotating component, and the magnet is limited within the limiting hole.

[0026] Understandably, the setting of the limiting hole increases the circumferential limitation of the rotating part on the magnet, preventing it from falling out of the rotating part during rotation and affecting its use. This improves the structural stability of the sewing machine fabric thickness detection device and ensures the accuracy of its detection results.

[0027] In one embodiment, the housing includes an upper cover plate and a lower cover plate, the upper cover plate and the lower cover plate being snapped together to form the mounting cavity;

[0028] One side of the upper cover plate has a movable groove, and the end of the probe rod away from the pressure foot plate extends into the mounting cavity from the movable groove.

[0029] Understandably, the movable groove allows the probe rod to have room to move at one end of the housing, thus preventing it from being restricted when rotating with the pressure foot plate and further ensuring the accuracy of the test results.

[0030] This application also provides the following technical solutions:

[0031] A sewing machine includes a presser foot plate, a presser foot arm, and a sewing machine fabric thickness detection device as described in any of the above embodiments. The sewing machine fabric thickness detection device includes a rotating component, a probe rod, and an angle detector. The rotating component is rotatably mounted on the presser foot arm. One end of the probe rod passes through the rotating component and is connected to the presser foot arm, and the other end extends in the height direction of the sewing machine and abuts against the rear end of the presser foot plate. The angle detector is mounted on the presser foot arm and is disposed relative to the rotating component.

[0032] The rear end of the presser foot plate drives the probe rod to move in the height direction of the sewing machine, causing the probe rod to drive the rotating component to rotate, and the angle detector detects the rotation angle of the rotating component.

[0033] Understandably, with this setup, the rotation angle of the rotating component detected by the angle detector can be converted into the displacement of the rear end of the presser foot in the height direction of the sewing machine, thereby obtaining the thickness of the fabric entering from the front end of the presser foot, so as to have sufficient time to adjust other components to adapt to the sewing process of the fabric.

[0034] Compared with existing technologies, the sewing machine fabric thickness detection device and sewing machine described herein utilize a detection mechanism mounted on the presser foot arm. One end of the first detection component abuts against the rear end of the presser foot plate. When the fabric enters from the front end of the presser foot plate, the rear end of the presser foot plate drives one end of the first detection component to move in the height direction of the sewing machine, causing the other end of the presser foot arm to rotate accordingly. A second detection component then detects and provides feedback on the rotation angle. The thickness of the fabric entering the presser foot plate can be obtained from the rotation angle. Thus, the fabric thickness can be detected as soon as it enters the front end of the presser foot plate, before it is fully below the presser foot plate. This allows for early detection of the fabric thickness, enabling adjustments to other components of the sewing machine to suit the sewing position or parameters of the fabric. Furthermore, since the two ends of the first detection component are connected to the presser foot arm and the presser foot plate respectively, when the sewing machine teeth move up and down, the presser foot arm and the presser foot plate move simultaneously. This allows the effects of the detection mechanism's movement on the presser foot arm and the presser foot plate to cancel each other out, thereby reducing the detection error of the fabric thickness and improving the accuracy of the fabric thickness detection. Attached Figure Description

[0035] To more clearly illustrate the technical solutions in the embodiments of this application or the conventional technology, the drawings used in the description of the embodiments or the conventional technology will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0036] Figure 1 This is a schematic diagram of the sewing machine fabric thickness detection device provided in this application after installation.

[0037] Figure 2 Provided for this application Figure 1 A schematic diagram of the explosion structure.

[0038] Figure 3 This is a cross-sectional structural diagram of the sewing machine fabric thickness detection device provided in this application.

[0039] Figure 4 This is a structural schematic diagram of the top cover plate and the first detection component provided in this application.

[0040] Figure 5 This is a schematic diagram of the structure of the lower cover plate and the second detection component provided in this application.

[0041] The component labels are as follows:

[0042] 100. Sewing machine fabric thickness detection device; 10. Housing; 11. Mounting cavity; 12. Upper cover plate; 121. Movable groove; 13. Lower cover plate; 20. Detection mechanism; 21. First detection component; 211. Rotating component; 2111. Through hole; 2112. Magnet; 2113. Limiting hole; 212. Detector rod; 2121. First section; 2122. Second section; 2123. Detection part; 213. Elastic component; 22. Second detection component; 221. Circuit board; 222. Angle detector; 223. Connector;

[0043] 201. Presser foot arm; 202. Presser foot plate; 2021. Front end; 2022. Rear end. Detailed Implementation

[0044] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application will be described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0045] It should be noted that when a component is referred to as being "fixed to" or "set on" another component, it can be directly on the other component or there may be an intermediate component. When a component is considered to be "connected to" another component, it can be directly connected to the other component or there may be an intermediate component present. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used in this application's specification are for illustrative purposes only and do not represent the only possible implementation.

[0046] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0047] In this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature and the second feature are in indirect contact through an intermediate medium. Furthermore, "above," "over," and "on top" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0048] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in this application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. The term "and / or" as used in this application includes any and all combinations of one or more of the associated listed items.

[0049] Please see Figures 1 to 5 This application provides a sewing machine fabric thickness detection device 100, mainly used for detecting the thickness of sewing fabric. It is installed on the presser foot arm 201 of the sewing machine and abuts against the rear end 2022 of the presser foot plate 202 in the length direction of the sewing machine. By detecting the displacement of the front end 2021 of the presser foot plate 202 in the height direction of the sewing machine, the thickness of the fabric can be detected before the fabric is completely under the presser foot plate 202 of the sewing machine. This allows the parameters of the presser bar and other components of the sewing machine to be adjusted in advance to a suitable position for the fabric to be sewn, thereby improving the sewing effect and reducing the detection error of the fabric thickness.

[0050] Specifically, the sewing machine fabric thickness detection device 100 includes a housing 10 and a detection mechanism 20. The housing 10 is mounted on the presser foot arm 201 and has a mounting cavity 11. The detection mechanism 20 includes a first detection component 21 and a second detection component 22. One end of the first detection component 21 is mounted in the mounting cavity 11, and the other end extends out of the mounting cavity 11 and extends in the height direction of the sewing machine to abut against the rear end 2022 of the presser foot plate 202. The second detection component 22 is disposed on a side wall of the mounting cavity 11 opposite to the first detection component 21. The first detection component 21 rotates with the rear end 2022 of the presser foot plate 202, and the second detection component 22 detects and feeds back the rotation angle of the first detection component 21.

[0051] It needs to be explained that the existing sewing machine fabric thickness detection device 100 is generally set on the presser foot 202 as a whole. After the fabric is fully inserted into the presser foot 202, the displacement of the presser foot 202 as a whole in the height direction of the sewing machine is detected to obtain the fabric thickness. However, such a structure and detection method may cause the parameter adjustment of the sewing machine's pressure bar and other components to lag, causing the fabric to become stuck when passing through the thread during the sewing process, affecting the sewing effect. In addition, since the sewing machine fabric thickness detection device 100 is only set on the presser foot 202, the presser foot 202 will also move during the adjustment of the sewing machine's teeth height, which may cause errors in the fabric thickness detection. This application addresses this issue by installing a detection mechanism 20 on the presser foot arm 201, with one end of the first detection component 21 abutting against the rear end 2022 of the presser foot plate 202. When the fabric enters from the front end 2021 of the presser foot plate 202, the rear end 2022 of the presser foot plate 202 drives one end of the first detection component 21 to move in the height direction of the sewing machine, causing the other end of the presser foot arm 201 to rotate accordingly. A second detection component 22 then detects and provides feedback on the rotation angle. The thickness of the fabric entering the presser foot plate 202 can be obtained from the rotation angle. Thus, the thickness of the fabric entering the front end 2021 of the presser foot plate 202 is determined. 1. The thickness of the fabric can be detected even before it is fully inserted under the presser foot plate 202, which means that the fabric thickness can be detected in advance. This allows other parts of the sewing machine to be adjusted in advance to the sewing position or parameters that are suitable for the fabric. At the same time, the two ends of the first detection component 21 are connected to the presser foot arm 201 and the presser foot plate 202, respectively. When the sewing machine teeth move up and down, the presser foot arm 201 and the presser foot plate 202 move simultaneously. In this way, the influence of the detection mechanism 20 moving on the presser foot arm 201 and the presser foot plate 202 can cancel each other out, thereby reducing the detection error of the fabric thickness and improving the accuracy of the fabric thickness detection.

[0052] In one embodiment, the housing 10 includes an upper cover plate 12 and a lower cover plate 13, which are snap-fitted together to form a mounting cavity 11. This makes it convenient to install and remove the upper cover plate 12 and the lower cover plate 13, and also facilitates the subsequent maintenance and replacement of the testing mechanism 20.

[0053] Here, the housing 10 and the presser foot arm 201 can be installed by setting screws or bolts, and the connection between the upper cover plate 12 and the lower cover plate 13 is not limited to the snap-fit ​​connection method, but can also be a sliding connection method, etc. The upper cover plate 12 and the lower cover plate 13 are connected by screws or bolts, and the housing 10 is installed and fixed on the presser foot arm 201.

[0054] like Figures 2 to 4As shown, the first detection component 21 includes a rotating member 211 and a probe rod 212. The rotating member 211 is rotatably mounted in the mounting cavity 11 and has a through hole 2111 in its circumferential direction. One end of the probe rod 212 passes through the through hole 2111, and the other end extends out of the mounting cavity 11 and extends in the height direction of the sewing machine to abut against the rear end 2022 of the presser foot plate 202. The probe rod 212 moves with the rear end 2022 of the presser foot plate 202 and drives the rotating member 211 to rotate. With this configuration, the thickness of the fabric can be detected in advance by the rotation angle of the rotating member 211 before the fabric is fully inserted into the presser foot plate 202.

[0055] In one embodiment, one side of the upper cover plate 12 has a movable groove 121, and the end of the probe 212 away from the pressure foot plate 202 extends into the mounting cavity 11 from the movable groove 121. It is understood that the movable groove 121 provides the probe 212 with a movable space at one end of the housing 10, so as to avoid its restriction when rotating with the pressure foot plate 202, and further ensure the accuracy of the detection results.

[0056] Here, the movable slot 121 extends in the height direction of the sewing machine to provide sufficient space for the movement of the probe 212.

[0057] Furthermore, the probe 212 has a first segment 2121 and a second segment 2122 connected to each other. The end of the first segment 2121 away from the second segment 2122 is provided with a through hole 2111. The end of the second segment 2122 away from the first segment 2121 is bent to form a probe part 2123. The probe part 2123 is abutted and fixed to the rear end 2022 of the pressure foot plate 202. The first segment 2121 and the second segment 2122 are set at an angle. It is understandable that the first segment 2121 and the second segment 2122 of the probe 212 are set at an angle to accommodate the installation of the detection mechanism 20. This allows the first segment 2121 to rotate within the housing 10 with the second segment 2122, preventing the first segment 2121 from interfering with the housing 10 due to the installation angle limitation when the second segment 2122 drives the first segment 2121 to rotate. This also increases the structural strength of the probe 212 during the motion transmission between the rotating component 211 and the pressure foot plate 202, preventing it from bending and being damaged under stress. At the same time, the second segment 2122 is bent to form the detection part 2123, which increases the contact area between the probe 212 and the pressure foot plate 202, preventing the probe 212 from being damaged due to insufficient contact area when the pressure foot plate 202 moves.

[0058] In one embodiment, the angle at the connection between the first segment 2121 and the second segment 2122 is set to an obtuse angle to ensure the installation and extension of the first segment 2121 and the second segment 2122.

[0059] Furthermore, the first segment 2121 is bent into two parts at a position relatively close to the middle of its length, so that the part away from the rotating part 211 can extend toward the pressure foot plate 202 and form a transition with the second segment 2122, thereby making the movement of the probe 212 smoother and more unrestricted.

[0060] In one embodiment, the first detection component 21 further includes an elastic element 213. The elastic element 213 is disposed in the mounting cavity 11, with one end fixed to the cavity wall of the mounting cavity 11, and the other end connected in a compressed manner to one end of the probe 212 that passes through the through hole 2111. It is understood that the elastic element 213 provides a force to the probe 212 that tightly abuts against the rear end 2022 of the presser foot plate 202, ensuring that the probe 212 always abuts against the rear end 2022 of the presser foot plate 202 and moves with the presser foot plate 202. This also improves the smoothness of the probe 212's movement, preventing overshooting or vibration of the probe 212 at the start of or during the movement of the rear end 2022 of the presser foot plate 202, which could affect the fabric detection results.

[0061] Here, the elastic element 213 can be a structure with elastic deformation and compression release tendency, such as a tension spring or spring.

[0062] like Figure 2 and Figure 5 As shown, the second detection component 22 includes a circuit board 221 and an angle detector 222. The circuit board 221 is disposed on one side wall of the mounting cavity 11, and the angle detector 222 is disposed relative to the rotating component 211 and connected to the circuit board 221. The angle detector 222 detects the rotation angle of the rotating component 211, and the circuit board 221 receives and feeds back the rotation angle.

[0063] In one embodiment, the angle detector 222 is a magnetic sensor, i.e., a magnetic encoder, and a magnet 2112 is mounted on the rotating part 211. The central axis of the magnetic sensor coincides with the central axis of the magnet 2112. The magnet 2112 rotates with the rotating part 211, and the magnetic sensor detects the rotation angle of the magnet 2112.

[0064] It should be explained that the angle detector 222 can also be a photoelectric sensor, a rotary transformer, or other structures that can detect the rotation angle of the rotating component 211, and a structure such as a grating disk that can cooperate with the angle detector 222 can also be installed on the rotating component 211. No specific limitations are made here.

[0065] Furthermore, taking the magnetic sensor and magnet 2112 as an example, the central axis of the rotating component 211 coincides with the central axis of the magnetic sensor, and a limiting hole 2113 is provided at the central axis of the rotating component 211, confining the magnet 2112 within the limiting hole 2113. It can be understood that the limiting hole 2113 increases the circumferential confinement of the magnet 2112 by the rotating component 211, preventing it from dislodging from the rotating component 211 during rotation, thus affecting its use. This improves the structural stability of the sewing machine fabric thickness detection device 100 and ensures the accuracy of its detection results.

[0066] In one embodiment, the sewing machine fabric thickness detection device 100 further includes an electrical control unit (not shown), which is connected to the circuit board 221 to obtain the rotation angle fed back by the circuit board 221 and convert the rotation angle into a corresponding height change value. Thus, by directly obtaining and generating the height change value through the electrical control unit, the intuitiveness of the fabric thickness detection results can be improved, enhancing the intelligence level and user experience of the sewing machine fabric thickness detection device 100.

[0067] It should be explained that the height change value here is the displacement of the rear end 2022 of the presser foot 202 in the height direction of the sewing machine, which is the thickness of the fabric.

[0068] In one embodiment, a connector 223 is also provided on the circuit board 221, and the angle detector 222 is connected to the control device through the connector 223 so that the control device can obtain relevant information about the rotation angle from the angle detector 222.

[0069] This application also provides the following technical solutions:

[0070] A sewing machine includes a presser foot plate 202, a presser foot arm 201, and a sewing machine fabric thickness detection device 100 as described in any of the above embodiments. The sewing machine fabric thickness detection device 100 includes a rotating component 211, a probe rod 212, and an angle detector 222. The rotating component 211 is rotatably mounted on the presser foot arm 201. One end of the probe rod 212 passes through the rotating component 211 and is connected to the presser foot arm 201, while the other end extends in the height direction of the sewing machine and abuts against the rear end 2022 of the presser foot plate 202. The angle detector 222 is mounted on the presser foot arm 201 and is positioned relative to the rotating component 211. The rear end 2022 of the presser foot plate 202 drives the probe rod 212 to move in the height direction of the sewing machine, causing the probe rod 212 to drive the rotating component 211 to rotate. The angle detector 222 detects the rotation angle of the rotating component 211.

[0071] With this setup, the rotation angle of the rotating component 211 detected by the angle detector 222 can be converted into the displacement of the rear end 2022 of the presser foot 202 in the height direction of the sewing machine, thereby obtaining the thickness of the fabric entering from the front end 2021 of the presser foot 202, so as to have sufficient time to adjust other components to adapt to the sewing process of the fabric.

[0072] The working principle of the sewing machine fabric thickness detection device 100 in this application for detecting fabric thickness is as follows:

[0073] When changing to a thicker fabric, the front end 2021 of the presser foot 202 will tilt upwards in the height direction of the sewing machine when it contacts the fabric. Correspondingly, the rear end 2022 of the presser foot 202 will move downwards and generate a height displacement. The detection part 2123 of the probe 212 is subjected to the force of the elastic element 213, and abuts against the rear end 2022 of the presser foot 202 and moves accordingly. At this time, the first section 2121 of the probe 212 drives the rotating part 211 to rotate. The angle detector 222 detects the signal of the rotation angle of the rotating part 211 and transmits it to the control circuit through the circuit board 221. The control circuit generates the fabric thickness change value according to the rotation angle change value of the rotating part 211.

[0074] When changing to a thinner fabric, the front end 2021 of the presser foot 202 contacts the fabric and moves downward in the height direction of the sewing machine. Correspondingly, the rear end 2022 of the presser foot 202 tilts upward and generates a height displacement. The detection part 2123 of the probe 212 is subjected to the force of the elastic element 213 and abuts against the rear end 2022 of the presser foot 202 and moves accordingly. At this time, the first section 2121 of the probe 212 drives the rotating element 211 to rotate. The angle detector 222 detects the signal of the rotation angle of the rotating element 211 and transmits it to the control circuit through the circuit board 221. The control circuit generates the fabric thickness change value according to the rotation angle change value of the rotating element 211.

[0075] Here, replacing with a thicker or thinner fabric involves comparing it with the previous fabric being sewn. After obtaining the change in fabric thickness, a simple calculation is performed using the thickness of the previous fabric to determine the thickness of the new fabric.

[0076] It should be explained that when the sewing machine is sewing the initial fabric, the thickness change of the fabric generated is the thickness of the initial fabric.

[0077] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0078] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the scope of protection of this application. Therefore, the patent protection scope of this application should be determined by the appended claims.

Claims

1. A fabric thickness detection device for a sewing machine, installed on the presser foot arm of the sewing machine and abutting against the presser foot plate at the rear end of the sewing machine along its length, for detecting the displacement of the front end of the presser foot plate in the height direction of the sewing machine, characterized in that, The sewing machine fabric thickness detection device includes: The housing is mounted on the presser foot arm and has a mounting cavity; The testing mechanism includes a first testing component and a second testing component. One end of the first testing component is installed in the mounting cavity, and the other end extends out of the mounting cavity and extends in the height direction of the sewing machine to abut against the rear end of the presser foot plate. The second testing component is disposed on the side wall of the mounting cavity opposite to the first testing component. The first detection component rotates with the rear end of the pressure foot plate, and the second detection component detects and provides feedback on the rotation angle of the first detection component.

2. The sewing machine fabric thickness detection device according to claim 1, characterized in that, The first detection component includes a rotating component and a probe rod. The rotating component is rotatably mounted in the mounting cavity and has a through hole in its circumferential direction. One end of the probe rod passes through the through hole, and the other end extends out of the mounting cavity and extends in the height direction of the sewing machine to abut against the rear end of the presser foot plate. The probe rod moves with the rear end of the pressure foot plate and drives the rotating component to rotate.

3. The sewing machine fabric thickness detection device according to claim 2, characterized in that, The probe rod has a first section and a second section connected to each other. The first section has a through hole at the end away from the second section, and the second section is bent at the end away from the first section to form a probe part. The probe part is fixed to the rear end of the pressure foot plate. The first segment and the second segment are set at an angle.

4. The sewing machine fabric thickness detection device according to claim 2, characterized in that, The first detection component further includes an elastic element, which is disposed in the mounting cavity, with one end fixed to the cavity wall of the mounting cavity and the other end connected to the end of the probe rod that passes through the through hole in a compressed manner.

5. The sewing machine fabric thickness detection device according to claim 2, characterized in that, The second detection component includes a circuit board and an angle detector. The circuit board is disposed on one side wall of the mounting cavity, and the angle detector is disposed relative to the rotating component and connected to the circuit board. The angle detector detects the rotation angle of the rotating component, and the circuit board receives and feeds back the rotation angle.

6. The sewing machine fabric thickness detection device according to claim 5, characterized in that, The sewing machine fabric thickness detection device also includes an electrical control unit connected to the circuit board, which is used to obtain the rotation angle fed back by the circuit board and convert the rotation angle into a height change value.

7. The sewing machine fabric thickness detection device according to claim 5, characterized in that, The angle detector uses a magnetic sensor, and a magnet is mounted on the rotating part, with the central axis of the magnetic sensor coinciding with the central axis of the magnet. The magnet rotates with the rotating component, and the magnetic sensor detects the rotation angle of the magnet.

8. The sewing machine fabric thickness detection device according to claim 7, characterized in that, A limiting hole is provided at the central axis of the rotating component, and the magnet is limited within the limiting hole.

9. The sewing machine fabric thickness detection device according to claim 2, characterized in that, The housing includes an upper cover plate and a lower cover plate, the upper cover plate and the lower cover plate being snapped together to form the mounting cavity; One side of the upper cover plate has a movable groove, and the end of the probe rod away from the pressure foot plate extends into the mounting cavity from the movable groove.

10. A sewing machine, characterized in that, The sewing machine includes a presser foot plate, a presser foot arm, and a sewing machine fabric thickness detection device as described in any one of claims 1-9. The sewing machine fabric thickness detection device includes a rotating component, a probe rod, and an angle detector. The rotating component is rotatably mounted on the presser foot arm. One end of the probe rod passes through the rotating component and is connected to the presser foot arm. The other end extends in the height direction of the sewing machine and abuts against the rear end of the presser foot plate. The angle detector is mounted on the presser foot arm and is positioned relative to the rotating component. The rear end of the presser foot plate drives the probe rod to move in the height direction of the sewing machine, causing the probe rod to drive the rotating component to rotate, and the angle detector detects the rotation angle of the rotating component.

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