FPC expansion and contraction detection device

Abstract

The present application discloses an FPC expansion and contraction detection device, which relates to the technical field of automotive electronics, including a detection instrument and an auxiliary instrument; the detection instrument includes a workbench and a detection lens; the auxiliary instrument includes a chassis, a cover plate and a boundary structure; the boundary structure forms a plurality of placement areas on the top of the chassis; the cover plate is transparent, and the cover plate is movably connected to the chassis, and when the cover plate moves to the extreme position in the direction close to the chassis, the cover plate can cover a plurality of the placement areas at the same time. The present application can effectively ensure the accuracy of measuring the size of the copper plate after shrinkage on the FPC, and at the same time can make the measurement process more convenient and quick, and improve the measurement effect and efficiency.

Description

Technical Field

[0001] The present application relates to the technical field of automotive electronics, and in particular to an FPC expansion and contraction detection device. Background Art

[0002] FPC, or flexible printed circuit board, is a flexible printed circuit board. It is mainly made of polyester film or polyimide as the base material, and has the characteristics of high wiring density, light weight, thin thickness and good bendability, so it is widely used in various fields.

[0003] At present, with the continuous development of electronic technology, flexible hollow boards have been widely used in the field of automotive electronics, and are often used in vehicle brake control systems, etc., and can control the mechanical structure inside the vehicle.

[0004] During the FPC processing, the copper plate will expand and shrink, and the dimensions of the copper plate in the X-axis direction and the Y-axis direction will be affected by the expansion and contraction. Therefore, after the FPC copper plate is processed, it is generally necessary to measure the size of the copper plate with high precision so that when the protective film is pasted on the copper plate during the subsequent FPC processing, the size of the protective film can be adjusted accordingly to match the size of the copper plate after expansion and contraction.

[0005] Usually, the size of the copper plate after expansion and contraction is measured with high precision using a two-dimensional instrument detection device. After the FPC processed by the copper plate is placed on the two-dimensional instrument detection device, the device can be started for measurement. However, since the copper plate is prone to bending and wrinkling during the FPC processing, the copper plate is not measured in a fully stretched state, which will affect the accuracy of the measurement results and will also affect the subsequent size adjustment of the protective film. Summary of the invention

[0006] The present application provides an FPC expansion and contraction detection device, which can effectively ensure the accuracy of measuring the size of the copper plate after shrinkage on the FPC, and at the same time can make the measurement process more convenient and quick, and improve the measurement effect and efficiency.

[0007] The present application provides an FPC expansion and contraction detection device, which adopts the following technical solution:

[0008] An FPC expansion and contraction detection device, applied to the above-mentioned FPC expansion and contraction detection method, comprises a detection instrument and an auxiliary instrument;

[0009] The detection instrument includes a workbench and a detection lens; a detection space for the FPC placement detection is provided above the workbench, and the detection lens is movably connected to the workbench, is located in the detection space and can move in the detection space, and can shoot and detect the bottom thereof;

[0010] The auxiliary instrument includes a chassis, a cover plate and a boundary structure; the boundary structure is arranged on the top surface of the chassis, and a plurality of placement areas for the FPC are formed on the top of the chassis, and the dimension of the boundary structure along the thickness direction of the chassis is not greater than the thickness dimension of the FPC; the cover plate is transparent, and is movably connected to the chassis. When the cover plate moves to an extreme position in a direction close to the chassis, the cover plate can contact and resist the boundary structure and cover a plurality of the placement areas at the same time.

[0011] By adopting the above technical solution, the user can arrange multiple FPCs on the chassis conveniently, and at the same time, the user can apply pressure to the multiple FPCs through the cover plate to drive them to stretch and flatten before the expansion and contraction detection, so that the subsequent expansion and contraction detection of multiple FPCs can be carried out in a stretched and flat state to improve the accuracy of the detection results.

[0012] Optionally, the boundary structure is elastic.

[0013] By adopting the above technical solution, the FPC may come into contact with the boundary structure during the process of arrangement and stretching and flattening, which can effectively reduce the wear of the FPC caused by the contact between the two, so as to ensure the quality of the FPC after expansion and contraction detection.

[0014] Optionally, the boundary structure includes a plurality of boundary components, and the plurality of boundary components are distributed in a rectangular array on the top of the chassis;

[0015] The demarcation component includes two demarcation pieces, which are connected to the chassis. The length directions of the two demarcation pieces are perpendicular to each other and are located at the corners corresponding to the placement area.

[0016] By adopting the above technical solution, it is convenient for the user to determine the placement position of the PFC in the placement area, and at the same time, the placement area can be adapted to the placement of PFCs of different sizes.

[0017] Optionally, the surface of the dividing piece in contact with the FPC is an arc surface, the dividing piece is rotatably connected to the chassis, and the rotation axis of the dividing piece is parallel to its own length direction.

[0018] By adopting the above technical solution, the wear on the FPC caused by the contact between the FPC and the dividing piece can be further reduced; and when the FPC is placed and stretched flat under pressure, the force exerted by the FPC on the dividing piece can drive the dividing piece to rotate, so as to further reduce the wear on the FPC caused by this process.

[0019] Optionally, a first elastic member is provided between the dividing member and the chassis, and two ends of the first elastic member are respectively connected to the dividing member and the chassis, and can drive the dividing member to rotate in a direction approaching the corresponding placement area.

[0020] By adopting the above technical solution, when the FPC applies force to the dividing piece to drive the dividing piece to rotate, the force applied by the first elastic piece to the dividing piece has the effect of suppressing the rotation of the dividing piece, so that the FPC can automatically displace and adjust its position in the placement space under the reaction force of the dividing piece, ensuring that the FPC is stretched flat while facilitating the arrangement of the FPC.

[0021] Optionally, the position of the rotation axis of the dividing piece is lower than the position of the top surface of the chassis, and when the dividing piece is rotated to the extreme position in the direction close to the corresponding placement area, the distance of the dividing piece above the top surface of the chassis is equal to the thickness of the FPC.

[0022] By adopting the above technical solution, when the cover plate applies pressure to the FPC to stretch it flat, it can also drive the dividing piece to maintain a stable position, thereby reducing the probability that the dividing piece cannot be reset under the force of the first elastic piece due to excessive force exerted by the FPC on the dividing piece, so as to further ensure the arrangement effect of the FPC in the placement area; at the same time, the dividing piece can also effectively prevent the cover plate from applying excessive pressure to the FPC, causing the quality of the FPC to be affected.

[0023] Optionally, the cover plate is slidably connected to the chassis, the cover plate is provided with a plurality of sliding blocks, the chassis is correspondingly provided with a plurality of first sliding grooves, and the first sliding grooves extend along the thickness direction of the chassis;

[0024] The chassis is provided with second elastic members in the first sliding grooves. When the sliding block slides with the first sliding groove, the cover plate is aligned with the chassis along the extension direction of the first sliding groove. The two ends of the second elastic member are respectively connected to the sliding block and the chassis, which has a tendency to drive the cover plate to slide in the direction away from the chassis, and the gravity of the cover plate is greater than the force of the second elastic members.

[0025] By adopting the above technical solution, the user can use the cover plate to apply pressure to the FPC, and at the same time reduce the impact force on the FPC during the downward sliding of the cover plate, thereby further reducing the probability of the FPC being damaged during the process of being stretched and flattened under pressure.

[0026] Optionally, a plurality of second sliding grooves are correspondingly provided on the chassis, and the second sliding grooves are connected to the corresponding first sliding grooves; when the sliding block slides along the second sliding groove in a direction away from the corresponding first sliding groove to an extreme position, the cover plate leaves from the top of the chassis.

[0027] By adopting the above technical solution, the user can conveniently control the cover to slide away from the top of the chassis, so that the user can arrange multiple FPCs on the chassis, thereby further making the measurement process more convenient and quick, and improving the measurement effect and efficiency.

[0028] In summary, the present application includes at least one of the following beneficial effects:

[0029] 1. It can arrange multiple FPCs neatly at the same time, and can apply pressure to multiple FPCs at the same time to make them stretch and flat, so as to effectively ensure the accuracy of measuring the size of the copper plate after the FPC rises and shrinks;

[0030] 2. It can make the arrangement of FPC and the stretching and flattening of FPC more convenient and quick, thereby effectively improving the effect and efficiency of FPC expansion and contraction detection;

[0031] 3. It can effectively reduce the probability of damage during the arrangement and compression and stretching of FPC, thereby effectively ensuring the quality of FPC after inspection;

[0032] 4. During the process of being stretched and flattened under pressure, the FPC can adjust its position by itself under the reaction force of the boundary piece, reducing the probability that the edge of the FPC is blocked by the boundary piece and the detection is affected. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 This is a schematic diagram of the structure of an FPC expansion and contraction detection device when the FPC is arranged in an embodiment of the present application;

[0034] Figure 2 This is a structural schematic diagram of an FPC expansion and contraction detection device according to an embodiment of the present application when the FPC is leveled;

[0035] Figure 3 It is a cross-sectional view of an auxiliary instrument when arranging FPC in an FPC expansion and contraction detection device according to an embodiment of the present application;

[0036] Figure 4 It is a cross-sectional view of an auxiliary instrument when leveling FPC in an FPC expansion and contraction detection device according to an embodiment of the present application;

[0037] Figure 5 It is a partial cross-sectional view of an FPC expansion and contraction detection device of an embodiment of the present application when the FPC is arranged;

[0038] Figure 6 It is a partial cross-sectional view of an FPC expansion and contraction detection device according to an embodiment of the present application when the FPC is flattened.

[0039] Explanation of the reference numerals in the accompanying drawings: 1. Detection instrument; 11. Workbench; 12. Detection lens; 13. Mounting seat; 14. Detection space; 2. Auxiliary instrument; 21. Chassis; 211. Groove; 212. Boss; 213. First sliding groove; 214. Second sliding groove; 22. Dividing structure; 221. Dividing assembly; 2211. Dividing piece; 2212. First elastic piece; 23. Cover plate; 231. Sliding block; 24. Placement area; 25. Second elastic piece; 26. Abutment piece; 3. FPC. DETAILED DESCRIPTION

[0040] The following is combined with Figure 1-6 This application is described in further detail.

[0041] Reference Figure 1 and Figure 2 The embodiment of the present application discloses an FPC expansion and contraction detection device, which is applied to the expansion and contraction detection of FPC, including a detection instrument 1 with expansion and contraction detection function and an auxiliary instrument 2 for assisting in arranging and stretching a plurality of FPCs 3 flat.

[0042] The testing instrument 1 comprises a workbench 11 and a testing lens 12. The workbench 11 is mainly used for placing the FPC 3 to be tested for expansion and contraction; and the testing lens 12 is used for performing image measurement of the X-axis and Y-axis dimensions of the FPC 3 placed on the workbench 11.

[0043] The workbench 11 is in a rectangular parallelepiped structure as a whole. The top of the workbench 11 has a horizontal plane and a detection space 14 above it for the FPC 3 to be placed thereon for expansion and contraction detection.

[0044] The top of the workbench 11 is movably connected with a mounting seat 13 for mounting the detection lens 12. The mounting seat 13 is an arched structure as a whole, and its movement direction is parallel to the width direction of the workbench 11; the detection lens 12 is movably connected to the mounting seat 13, and can move along the length direction of the mounting seat 13, that is, the length direction of the workbench 11; the detection lens 12 can perform video measurement of the objects below in the vertical downward direction, and the expansion and contraction detection of the FPC3 placed on the workbench 11 can be performed by controlling the movement of the mounting seat 13 and the movement of the detection lens 12. In this embodiment, the preferred detection instrument 1 is a two-dimensional detection device; since the two-dimensional detection device is a common prior art, it will not be described in detail here, and it is only briefly represented in the attached drawings.

[0045] The multiple FPCs 3 are placed on the workbench 11 through the auxiliary instrument 2 so that the multiple FPCs 3 are located below the detection lens 12 , which is convenient for the user to perform expansion and contraction detection on the multiple FPCs 3 .

[0046] Reference Figure 1 and Figure 3 The auxiliary instrument 2 includes a chassis 21, a boundary structure 22 and a cover plate 23. The chassis 21 is used to place multiple FPC3; the boundary structure 22 is used to facilitate the user to arrange multiple FPC3 on the chassis 21; and the cover plate 23 is used to apply pressure to multiple FPC3 to make them stretch and flat, thereby improving the accuracy of expansion and contraction detection.

[0047] The chassis 21 is a rectangular plate-shaped structure as a whole, and the boundary structure 22 is distributed on the surface of one side of the chassis 21 in the thickness direction. The boundary structure 22 includes a plurality of boundary components 221, which are distributed in a rectangular array on the surface of the chassis 21, and a plurality of placement areas 24 for placing a single FPC 3 are formed on the surface of the chassis 21. In this embodiment, the placement area 24 is preferably in a rectangular shape; and preferably, there are two rows of boundary components 221 distributed on the chassis 21.

[0048] Reference Figure 3 and Figure 4 The boundary component 221 includes two boundary members 2211 and two first elastic members 2212 .

[0049] The boundary member 2211 is elastic and has a hardness significantly lower than that of the FPC 3. In this embodiment, the boundary member 2211 is preferably a rubber product.

[0050] Reference Figure 1 and Figure 3 The demarcation piece 2211 as a whole is a nearly circular long strip structure with a variable radius in cross section (similar to a cam). The two demarcation pieces 2211 in the same demarcation assembly 221 are installed on the chassis 21 in a position state in which the length directions are perpendicular to each other, and the length directions of the two demarcations are respectively parallel to the length direction and the width direction of the chassis 21. One end of the two demarcation pieces 2211 in the length direction is close to each other and is located at the corner position of the same placement area 24, so that the user can place the FPC3 in the corresponding placement area 24 with the two demarcation pieces 2211 as the boundary, so that the two sides of the same corner of the FPC3 are in contact with the two demarcation pieces 2211. In this embodiment, it is preferred that the placement area 24 can accommodate FPC3 of different sizes, and it is preferred that the length dimension of the demarcation piece 2211 is greater than the size of the smallest FPC3.

[0051] Reference Figure 3 and Figure 4The dividing piece 2211 is rotatably connected to the chassis 21, and its rotation axis is parallel to its own length direction and coincides with the axis of its own cam structure. A groove 211 that can be matched with the dividing piece 2211 is correspondingly opened on the surface of the chassis 21, and the rotation axis of the dividing piece 2211 is located in the corresponding groove 211; when the end with the largest radius on the dividing piece 2211 is rotated to the extreme position close to the corresponding placement area 24, the dividing piece 2211 is just completely matched with the corresponding groove 211, and at this time, the height dimension of the dividing piece 2211 protruding from the surface of the chassis 21 is equal to the thickness dimension of FPC3.

[0052] The first elastic member 2212 is also installed in the corresponding groove 211, and the two ends of the first elastic member 2212 are respectively fixedly connected to the corresponding dividing member 2211 and the chassis 21, and have a tendency to drive the end with the largest radius on the corresponding dividing member 2211 to rotate to the extreme position close to the corresponding placement area 24. In this embodiment, the first elastic member 2212 is preferably a torsion spring; since the torsion spring is a common prior art, it will not be described in detail here, and its structure is omitted in the drawings, and only its installation position is shown.

[0053] Reference Figure 2 and Figure 4 The cover plate 23 is a transparent rectangular plate-shaped structure as a whole, and the size of the cover plate 23 matches the size of the chassis 21. Both ends of the chassis 21 in the length direction protrude outward along the thickness direction of the chassis 21 to form a boss 212 for connecting the cover plate 23 and the chassis 21. The cover plate 23 is movably connected to the chassis 21, and a space for the cover plate 23 to move in and out is formed between the two bosses 212 on one side of the chassis 21. In this embodiment, the cover plate 23 is preferably made of optical glass.

[0054] Reference Figure 1 and Figure 5 , both ends of the cover plate 23 in the length direction have sliding blocks, and the two sliding blocks are close to one side of the cover plate 23 in the width direction respectively; the chassis 21 is provided with a first sliding groove 213 and a second sliding groove 214 adapted to the sliding blocks on the side of the boss 212 close to the boundary structure 22. In this embodiment, in order to make the sliding process of the cover plate 23 relative to the chassis 21 smoother, the sliding block is preferably a wheel structure that can rotate relative to the cover plate 23, and the rotation axis is parallel to the length direction of the cover plate 23.

[0055] Reference Figure 2 and Figure 6 The first sliding groove 213 is located at a section in the length direction of the boss 212 and extends along the thickness direction of the chassis 21; when the two sliding blocks on the cover plate 23 are respectively located in the two first sliding grooves 213, the cover plate 23 and the chassis 21 are aligned along the extension direction of the first sliding grooves 213, and the cover plate 23 can cover multiple placement areas 24 at the same time.

[0056] Reference Figure 5 and Figure 6 The chassis 21 is provided with a second elastic member 25 and abutting member 26 in both first sliding grooves 213. The two ends of the second elastic member 25 are respectively fixedly connected with the abutting member 26 and the groove wall of the first sliding groove 213 close to the chassis 21 along its own extension direction, and the second elastic member 25 has a tendency to drive the abutting member 26 to move in the direction away from the chassis 21 along the extension direction of the first sliding groove 213, and the abutting member 26 is kept in the first sliding groove 213 under the action of the second elastic member 25. In this embodiment, the second elastic member 25 is preferably a spring.

[0057] Reference Figure 2 and Figure 6 When the two sliding blocks on the cover plate 23 are respectively slidably matched with the two first sliding grooves 213 and are located at a position where the first sliding grooves 213 are away from the chassis 21 along their own extension direction, the sliding blocks can contact and abut against the adjacent abutment members 26, and a certain distance is maintained between the cover plate 23 and the boundary structure 22; at this time, under the action of the gravity of the cover plate 23 itself, the cover plate 23 can overcome the force of the second elastic member 25 and slide in the direction close to the chassis 21 until the cover plate 23 contacts and abuts against the multiple boundary members 2211 and FPC3 below and applies pressure to the FPC3 to make it stretch and flat; in this process, the speed at which the cover plate 23 slides freely downward will gradually decrease under the resistance of the second elastic member 25, so as to effectively reduce the impact force on the FPC3 after the cover plate 23 slides downward and contacts the FPC3.

[0058] Reference Figure 5 and Figure 6 The second sliding groove 214 extends along the length direction of the boss 212 in an arc track, and one end is connected with the end of the first sliding groove 213 on the same boss 212 along its own extension direction away from the chassis 21. In this embodiment, it is preferred that the opening of the arc track of the second sliding groove 214 faces the chassis 21, the position where the second sliding groove 214 communicates with the first sliding groove 213 is the arc bottom, and the middle position of the second sliding groove 214 along the length direction of the boss 212 is the arc top.

[0059] Reference Figure 1 and Figure 5 The cover 23 is controlled to move by sliding the sliding block along the second sliding groove 214. During the process of the sliding block sliding from one end of the second sliding groove 214 close to the first sliding groove 213 to the second sliding groove 214 away from the first sliding groove 213, the cover 23 will first rise and then fall relative to the chassis 21, and leave from the top of the chassis 21.

[0060] When the two sliding blocks on the cover plate 23 are respectively slidably matched with the two second sliding grooves 214 and are located at a position where the second sliding grooves 214 are away from the first sliding grooves 213, the side of the cover plate 23 away from the sliding blocks will contact the plane where the chassis 21 is located under the action of its own gravity, and at this time, it is convenient for the user to place multiple FPCs 3 in the corresponding placement area 24. In practical applications, in order to reduce the wear of the cover plate 23 during use, it is preferred that the portion of the cover plate 23 that can contact the plane where the chassis 21 is located has an anti-collision design, such as a protective pad, rounded corners, etc.

[0061] The implementation principle of an FPC expansion and contraction detection device in the embodiment of the present application is:

[0062] After placing the auxiliary instrument 2 on the workbench 11 and arranging the chassis 21 neatly, apply force to the cover plate 23 to control the cover plate 23 to slide relative to the chassis 21 in a direction away from the chassis 21, so that a plurality of placement areas 24 for placing FPC3 are exposed; then place a plurality of FPC3 in different placement areas 24, so that the two sides of the same corner of the FPC3 are respectively in contact with and against the two boundary pieces 2211 in the same boundary component 221;

[0063] After the placement of the multiple FPC3s is completed, force is applied to the cover plate 23 to control the cover plate 23 to slide relative to the chassis 21 toward the chassis 21. After the cover plate 23 and the chassis 21 are aligned along the thickness direction of the chassis 21, the cover plate 23 is released to slide along the thickness direction of the chassis 21 toward the chassis 21 under the action of its own gravity until the cover plate 23 simultaneously contacts and abuts against the multiple boundary pieces 2211 and the multiple FPC3s and applies pressure to the multiple FPC3s, so that the FPC3s can be fully stretched and flattened in the corresponding placement area 24, so as to ensure the accuracy of the test results when the expansion and contraction tests of the multiple FPC3s are performed later;

[0064] When the cover plate 23 slides relative to the chassis 21 under the action of its own gravity, the second elastic member 25 has resistance to it, which can effectively reduce the sliding speed of the cover plate 23, so as to effectively reduce the impact force on the FPC3 when the cover plate 23 contacts the FPC3, thereby reducing the probability of the FPC3 being damaged by the impact force of the cover plate 23;

[0065] During the process of the cover plate 23 applying pressure to the FPC3, the FPC3 will stretch in the corresponding placement area 24 first. During the stretching process of the FPC3, the force exerted on the two boundary pieces 2211 in contact with it will drive the boundary pieces 2211 to rotate to overcome the force of the corresponding first elastic piece 2212. At this time, the height of the boundary piece 2211 protruding from the surface of the chassis 21 will be greater than the thickness of the FPC3, so that the boundary piece 2211 can actively contact the cover plate 23 that is applying pressure to the FPC3, thereby slowing down the speed at which the cover plate 23 applies pressure to the FPC3, and further reducing the probability of the FPC3 being damaged during the pressure process; then, The dividing piece 2211 that actively contacts the cover plate 23 will rotate and reset under the force applied by the cover plate 23. During the rotation and reset process of the dividing piece 2211, the FPC3 that contacts with it can be driven to move within the corresponding placement area 24, so that when the dividing piece 2211 rotates and resets, the corresponding FPC3 is in a position where the stretching and flattening is completed and the two side plates at the same corner are just in contact with and abut against the two dividing pieces 2211 of the same dividing component 221, thereby reducing the probability that the edge position of the FPC3 is blocked by the dividing piece 2211 after stretching and flattening, thereby further improving the accuracy of the detection results of subsequent expansion and contraction detection of multiple FPC3s.

[0066] The above are all preferred embodiments of the present application, and the protection scope of the present application is not limited thereto. Therefore, any equivalent changes made according to the structure, shape, and principle of the present application should be included in the protection scope of the present application.

Claims

1. An FPC expansion and contraction detection device, characterized in that: It comprises a detection instrument (1) and an auxiliary instrument (2); The detection instrument (1) comprises a workbench (11) and a detection lens (12); a detection space (14) is provided above the workbench (11) for placing the FPC (3) for detection; the detection lens (12) is movably connected to the workbench (11), is located in the detection space (14) and is movable in the detection space (14), and is capable of photographing and detecting the area below the workbench; The auxiliary instrument (2) comprises a chassis (21), a cover plate (23) and a boundary structure (22); the boundary structure (22) is arranged on the top surface of the chassis (21), and a plurality of placement areas (24) for placing the FPC (3) are formed on the top of the chassis (21), and the dimension of the boundary structure (22) along the thickness direction of the chassis (21) is not greater than the thickness dimension of the FPC (3); the cover plate (23) is transparent, and the cover plate (23) is movably connected to the chassis (21). When the cover plate (23) moves in a direction close to the chassis (21) to an extreme position, the cover plate (23) can contact and abut against the boundary structure (22) and simultaneously cover the plurality of placement areas (24); The cover plate (23) is slidably connected to the base plate (21); the cover plate (23) is provided with a plurality of sliding blocks (231); the base plate (21) is correspondingly provided with a plurality of first sliding grooves (213); and the first sliding grooves (213) extend along the thickness direction of the base plate (21); The chassis (21) is provided with a second elastic member (25) in each of the first sliding grooves (213); when the sliding block (231) slides with the first sliding groove (213), the cover plate (23) is aligned with the chassis (21) along the extension direction of the first sliding groove (213); two ends of the second elastic member (25) are respectively connected to the sliding block (231) and the chassis (21), and have a tendency to drive the cover plate (23) to slide in a direction away from the chassis (21); and the gravity of the cover plate (23) is greater than the action force of the second elastic members (25); A plurality of second sliding grooves (214) are correspondingly formed on the chassis (21), and the second sliding grooves (214) are in communication with the corresponding first sliding grooves (213); when the sliding block (231) slides along the second sliding grooves (214) in a direction away from the corresponding first sliding grooves (213) to an extreme position, the cover plate (23) leaves from above the chassis (21).

2. The FPC expansion and contraction detection device according to claim 1, characterized in that: The boundary structure (22) is elastic.

3. The FPC expansion and contraction detection device according to claim 2, characterized in that: The boundary structure (22) comprises a plurality of boundary components (221), and the plurality of boundary components (221) are distributed in a rectangular array on the top of the bottom plate (21); The boundary component (221) comprises two boundary pieces (2211), the boundary pieces (2211) being connected to the chassis (21), the length directions of the two boundary pieces (2211) being perpendicular to each other and being located at corner positions corresponding to the placement area (24).

4. The FPC expansion and contraction detection device according to claim 3, characterized in that: The surface of the dividing piece (2211) in contact with the FPC (3) is an arc surface, the dividing piece (2211) is rotatably connected to the chassis (21), and the rotation axis of the dividing piece (2211) is parallel to its own length direction.

5. The FPC expansion and contraction detection device according to claim 4, characterized in that: A first elastic member (2212) is provided between the dividing member (2211) and the chassis (21); two ends of the first elastic member (2212) are respectively connected to the dividing member (2211) and the chassis (21), and can drive the dividing member (2211) to rotate in a direction approaching the corresponding placement area (24).

6. The FPC expansion and contraction detection device according to claim 5, characterized in that: The position of the rotation axis of the dividing piece (2211) is lower than the position of the top surface of the chassis (21); when the dividing piece (2211) is rotated to an extreme position in a direction close to the corresponding placement area (24), the distance that the dividing piece (2211) is higher than the top surface of the chassis (21) is equal to the thickness of the FPC (3).

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