Anti-cheating visual chart fixing device and vision detection device

Abstract

The utility model relates to the field of ophthalmology examination equipment, and provides an anti-cheating visual chart fixing device and a vision detection device, which comprise a frame body, a first rotary connecting seat, a second rotary connecting seat and a linear driving device. One end of the first rotary connecting seat is rotationally connected with the frame body, and the other end is inserted into the visual chart. One end of the second rotary connecting seat is rotationally connected with the linear driving device and is connected with the frame body through the linear driving device, and the other end of the second rotary connecting seat is inserted into the visual chart. The first rotating connecting base and the second rotating connecting base are oppositely arranged, and the rotating axes of the two rotating connecting bases are collinear. The visual chart can be inserted between the first rotary connecting base and the second rotary connecting base, and the visual chart can be detached when the linear driving device drives the second rotary connecting base to be away from the first rotary connecting base. Therefore, the selectable number of the visual chart is increased, and the problem that the examined person cheats in the mode of recording the form of the pattern on the visual chart in advance can be effectively avoided.

Description

Technical Field

[0001] The utility model relates to the technical field of ophthalmic examination equipment, in particular to an anti-cheating visual acuity chart fixing device and a visual acuity detection device. Background Art

[0002] A visual acuity chart is a chart used to measure visual acuity, including the international standard visual acuity chart, the logarithmic visual acuity chart, the Landolt ring visual acuity chart, etc. The commonly used one at present is the international standard visual acuity chart.

[0003] In some cases, some people who attempt to cheat will memorize the pattern form on the visual acuity chart before the visual acuity examination to achieve cheating. For this reason, a double-sided visual acuity chart is disclosed in the related art. The visual acuity chart can be rotated. Before the visual acuity examination, one of the sides is randomly oriented towards the examinee, thereby achieving the anti-cheating effect.

[0004] However, the above technical solution still has deficiencies in actual use. Cheating people can memorize the pattern forms on both sides of the visual acuity chart in advance for cheating. Therefore, the double-sided visual acuity chart still cannot solve the cheating problem. Summary of the Utility Model

[0005] The utility model aims to solve at least one of the technical problems existing in the prior art. For this purpose, the utility model provides an anti-cheating visual acuity chart fixing device and a visual acuity detection device, aiming to solve the problem that the examinee can memorize the pattern form on the visual acuity chart in advance for cheating in the related art.

[0006] The utility model provides an anti-cheating visual acuity chart fixing device, comprising:

[0007] A frame body;

[0008] A first rotating connection seat, one end of the first rotating connection seat is rotatably connected to the frame body, the other end of the first rotating connection seat is used for plugging and connecting with the visual acuity chart, and the first rotating connection seat is rotationally locked with the visual acuity chart;

[0009] A linear driving device, the linear driving device is connected to the frame body and is located on the side opposite to the first rotating connection seat, and the movement direction of the moving end of the linear driving device is parallel to the rotation axis of the first rotating connection seat;

[0010] A second rotating connection seat, one end of the second rotating connection seat is rotatably connected to the moving end of the linear driving device, the other end of the second rotating connection seat is used for plugging and connecting with the visual acuity chart, and the second rotating connection seat is rotationally locked with the visual acuity chart. The rotation axes of the second rotating connection seat and the first rotating connection seat are collinear, and the second rotating connection seat is used to move in a direction close to or away from the first rotating connection seat along with the linear driving device.

[0011] According to the anti-cheating visual acuity chart fixing device provided by the present utility model, it further includes a limiting component. The limiting component is arranged on the frame body, and the part of the limiting component close to the visual acuity chart is used to contact or separate from the visual acuity chart. When the limiting component contacts the visual acuity chart, the limiting component is used to limit the rotation of the visual acuity chart.

[0012] According to the anti-cheating visual acuity chart fixing device provided by the present utility model, the frame body includes:

[0013] A base;

[0014] An installation frame. The installation frame is arranged on the top of the base, and the first rotating connection seat and the linear driving device are arranged on opposite sides of the installation frame.

[0015] According to the anti-cheating visual acuity chart fixing device provided by the present utility model, the first rotating connection seat is arranged at the inner bottom of the installation frame, the linear driving device is arranged at the top of the installation frame, the second rotating connection seat is arranged at the bottom of the linear driving device. The rotation axes of the first rotating connection seat and the second rotating connection seat are along the vertical direction, and the rotation axes of the two are collinear. The movement direction of the linear driving device is along the vertical direction;

[0016] Or, the first rotating connection seat and the linear driving device are respectively arranged on the left and right sides inside the installation frame, the second rotating connection seat is arranged at one end of the linear driving device close to the first rotating connection seat. The rotation axes of the first rotating connection seat and the second rotating connection seat are along the left and right direction, and the rotation axes of the two are collinear. The movement direction of the linear driving device is along the left and right direction.

[0017] According to the anti-cheating visual acuity chart fixing device provided by the present utility model, the base includes a chassis and a lifting support rod. The lifting support rod is arranged between the chassis and the installation frame.

[0018] According to the anti-cheating visual acuity chart fixing device provided by the present utility model, both the first rotating connection seat and the second rotating connection seat include a connection block. A slot and a rotating shaft are arranged on the connection block. The slot and the rotating shaft are arranged on opposite sides of the connection block. The slot is in non-rotating connection with a plug at a corresponding position on the visual acuity chart. The rotating shaft of the first rotating connection seat is rotatably connected to the installation frame through a bearing, and the rotating shaft of the second rotating connection seat is rotatably connected to the driving end of the linear driving device.

[0019] According to the anti-cheating visual acuity chart fixing device provided by the present utility model, the linear driving device includes:

[0020] A sliding rod that penetrates both the inside and outside of the mounting frame, and the sliding rod is slidably connected to the mounting frame;

[0021] A handle provided at one end of the sliding rod outside the mounting frame;

[0022] A mounting block provided at one end of the sliding rod inside the mounting frame, and a second shaft hole is provided on the side of the mounting block away from the handle. The rotating shaft of the second rotating connection seat is rotatably connected to the second shaft hole through a bearing;

[0023] A reset member provided between the mounting block and the mounting frame;

[0024] When the handle drives the sliding rod to move outward from the mounting frame, the reset member stores energy. When the handle is released, the reset member releases elastic force to drive the mounting block to reset.

[0025] According to the anti-cheating visual acuity chart fixing device provided by the present invention, the limiting assembly includes a first linear telescopic mechanism and a blocking member. The first linear telescopic mechanism is fixedly connected to the frame body. The telescopic end of the first linear telescopic mechanism moves in a direction close to or away from the visual acuity chart. The blocking member is provided at the telescopic end of the first linear telescopic mechanism. When the telescopic end of the first linear telescopic mechanism drives the blocking member to move to a position in contact with the visual acuity chart, the blocking member restricts the rotation of the visual acuity chart.

[0026] According to the anti-cheating visual acuity chart fixing device provided by the present invention, the lifting support rod includes a fixed rod, a moving rod, and a second linear telescopic mechanism. The bottom end of the fixed rod is connected to the chassis. The moving rod is nested and connected to the top of the fixed rod. The second linear telescopic mechanism is provided between the fixed rod and the moving rod.

[0027] The present invention also provides a visual acuity detection device, including a visual acuity chart and the anti-cheating visual acuity chart fixing device as described above. The visual acuity chart is arranged between the first rotating connection seat and the second rotating connection seat of the anti-cheating visual acuity chart fixing device.

[0028] Due to the adoption of the above technical solutions, the present invention has the following advantages:

[0029] The anti-cheating eye chart fixing device provided by the utility model comprises a frame, a first rotating connection seat, a second rotating connection seat and a linear drive device. One end of the first rotating connection seat is rotatably connected to the frame, and the other end is plug-connected with the eye chart, and the first rotating connection seat is connected to the eye chart. The linear drive device is connected to the frame, located on the side opposite to the first rotating connection seat, and the movement direction is parallel to the rotation axis of the first rotating connection seat. One end of the second rotating connection seat is rotatably connected to the moving end of the linear drive device, and the other end is used for plug-connecting with the eye chart, and is connected to the eye chart. The rotation axes of the first rotating connection seat and the second rotating connection seat are collinear. When connected, the second rotating connection seat is first driven by the linear drive device to move in a direction away from the first rotating connection seat, and one of the connection ends of the eye chart is plugged with the first rotating connection seat, and then the other connection end of the eye chart is automatically aligned with the second rotating connection seat, and the linear drive device drives the second rotating connection seat to move in a direction close to the first rotating connection seat, and the connection end of the eye chart is plugged with the second rotating connection seat. At this time, the eye chart can rotate under the constraints of the first rotating connection seat and the second rotating connection seat. In this way, the anti-cheating eye chart fixing device provided by the utility model can realize the double-sided switching of the eye chart. At the same time, the first rotating connecting seat can be driven to move by the linear drive device to realize the replacement of the eye chart. Before checking the vision, one of the double-sided eye charts can be randomly selected to be installed on the anti-cheating eye chart fixing device, and one of the sides can be randomly selected for vision testing, thus increasing the number of eye charts that can be selected, and effectively preventing the problem of cheating by the person being checked by memorizing the shape of the pattern on the eye chart in advance.

[0030] Furthermore, in the vision detection device provided by the present invention, since the anti-cheating vision chart fixing device as described above is provided, it has the same advantages as described above. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0032] Figure 1 It is a front view of an anti-cheating eye chart fixing device provided by an embodiment of the utility model and equipped with an eye chart;

[0033] Figure 2 It is a cross-sectional view of an anti-cheating eye chart fixing device provided by an embodiment of the utility model and equipped with an eye chart;

[0034] Figure 3 yesFigure 2 Enlarged view of part A in

[0035] Figure 4 is Figure 2 the enlarged view of part B in

[0036] Reference numerals:

[0037] 100: First rotating connection base; 200: Second rotating connection base; 300: Visual acuity chart; 310: Plug; 320: Limiting hole; 410: Chassis; 420: Mounting frame; 421: First shaft hole; 431: Fixed rod; 432: Moving rod; 441: Motor; 442: Second lead screw; 443: First limiting groove; 444: First limiting block; 445: Threaded hole; 510: Connecting block; 520: Slot; 530: Rotating shaft; 610: Sliding rod; 620: Pulling handle; 630: Mounting block; 631: Second shaft hole; 640: Spring; 711: Sliding sleeve; 712: First lead screw; 713: Rotating handle; 714: Slide block; 720: Stop rod. Detailed implementation manners

[0038] To make the objectives, technical solutions and advantages of the present utility model clearer, the technical solutions in the present utility model will be clearly and completely described below with reference to the accompanying drawings in the present utility model. Apparently, the described embodiments are some but not all of the embodiments of the present utility model. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present utility model without making creative efforts shall fall within the protection scope of the present utility model.

[0039] In the description of the present utility model, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as a limitation to the present utility model.

[0040] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present utility model, "a plurality" means two or more unless otherwise specifically defined.

[0041] In the present utility model, unless otherwise clearly defined and limited, terms such as "installation", "connection", "linkage", "fixation" and the like shall be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral one; it may be a mechanical connection or an electrical connection; it may be a direct connection or an indirect connection through an intermediate medium, and it may be the internal communication between two components or the interaction relationship between two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.

[0042] In the present utility model, unless otherwise clearly defined and limited, the first feature being "on" or "under" the second feature may be that the first and second features are in direct contact, or the first and second features are in indirect contact through an intermediate medium. Moreover, the first feature being "above", "over" and "on top of" the second feature may be that the first feature is directly above or obliquely above the second feature, or merely indicates that the first feature is at a higher horizontal level than the second feature. The first feature being "under", "beneath" and "underneath" the second feature may be that the first feature is directly below or obliquely below the second feature, or merely indicates that the first feature is at a lower horizontal level than the second feature.

[0043] In the description of this specification, the descriptions with reference to terms such as "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. mean that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present utility model. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in a suitable manner in any one or more embodiments or examples. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0044] The present utility model provides an anti-cheating visual acuity chart fixing device. The visual acuity chart 300 can be inserted between the first rotating connection seat 100 and the second rotating connection seat 200 and rotates under the restraint of the first rotating connection seat 100 and the second rotating connection seat 200. The linear driving device can drive the second rotating connection seat 200 to move towards or away from the first rotating connection seat 100 to realize the connection or separation of the second rotating connection seat 200 and the visual acuity chart 300, facilitating the replacement of the visual acuity chart 300. Thus, the anti-cheating visual acuity chart fixing device provided by the present utility model can not only realize the double-sided rotation of the visual acuity chart 300, but also facilitate the replacement of the visual acuity chart 300, increasing the number of selectable visual acuity charts 300, and effectively preventing the problem of cheating by memorizing the pattern form of the visual acuity chart 300 in advance.

[0045] The following will combine with Figures 1 to 4 describe the anti-cheating visual acuity chart fixing device and visual acuity detection device of the present utility model.

[0046] An embodiment of the present utility model provides an anti-cheating visual acuity chart fixing device, which includes a frame body, a first rotating connection seat 100, a second rotating connection seat 200 and a linear driving device.

[0047] Both the first rotating connection seat 100 and the linear driving device are connected to the frame body. The second rotating connection seat 200 is connected to the frame body through the linear driving device, and can move in the direction of approaching or departing from the first rotating connection seat 100 along with the movement of the linear driving device.

[0048] One end of the first rotating connection seat 100 is rotatably connected to the frame body, and the other end is used for plugging and connecting with the connection end on the visual acuity chart 300, and the two are non-rotatablely connected. One end of the second rotating connection seat 200 is rotatably connected to the moving end of the linear driving device, and the other end is used for plugging and connecting with another connection end on the visual acuity chart 300, and the second rotating connection seat 200 is non-rotatablely connected to the visual acuity chart 300. The rotation axes of the first rotating connection seat 100 and the second rotating connection seat 200 are collinear. Correspondingly, the axes of the two connection ends of the visual acuity chart 300 are both located on the rotation axis.

[0049] The linear driving device is connected to the frame body, and the movement direction of the moving end of the linear driving device is parallel to the rotation axis of the first rotating connection seat 100 or the second rotating connection seat 200. In this way, the second rotating connection seat 200 can be driven to move in the direction of approaching or departing from the first rotating connection seat 100.

[0050] The linear driving device can drive the second rotating connection seat 200 to move between a first position and a second position. When it is necessary to install the visual acuity chart 300, first, the linear driving device drives the second rotating connection seat 200 to move to the second position away from the first rotating connection seat 100, so that the distance between the first rotating connection seat 100 and the second rotating connection seat 200 is greater than the distance between the two connection ends of the visual acuity chart 300. Then, one connection end of the visual acuity chart 300 is plugged and connected to the first rotating connection seat 100. At this time, the other connection end of the visual acuity chart 300 is automatically aligned with the second rotating connection seat 200. Then, the linear driving device drives the second rotating connection seat 200 to move to the first position to complete the plugging and connection of the corresponding connection end of the second rotating connection seat 200 and the visual acuity chart 300.

[0051] When the eye chart 300 needs to be disassembled, first drive the second rotating connection seat 200 to move to the second position through the linear drive device, so that the connection end between the second rotating connection seat 200 and the eye chart 300 is separated. Then, pull out the other connection end of the eye chart 300 from the first rotating connection seat 100, and the disassembly of the eye chart 300 is completed.

[0052] For the anti-cheating eye chart fixing device provided by the present utility model, in addition to being able to rotate the eye chart 300 to switch different detection surfaces facing the person to be detected, the eye chart 300 can also be replaced to prevent the person to be detected from cheating. In this way, the number of selectable eye charts 300 is increased, and the possibility of cheating is greatly reduced.

[0053] In some embodiments of the present utility model, a limiting component is further provided on the frame body. The part of the limiting component close to the eye chart 300 can move to a position in contact with or separated from the eye chart 300. When the tester installs the eye chart 300 and selects the detection surface of the eye chart 300, the part of the limiting component close to the eye chart 300 can be brought into contact with the eye chart 300. At this time, the limiting component blocks both sides of the eye chart 300 along the rotation direction, thereby restricting the rotation of the eye chart 300. When the tester needs to replace the detection surface of the eye chart 300, the part of the limiting component close to the eye chart 300 can be separated from the eye chart 300, and the limiting component no longer restricts the rotation of the eye chart 300.

[0054] In some embodiments of the present utility model, the above-mentioned frame body includes a base and a mounting frame 420.

[0055] Since the international standard eye chart is a rectangular structure, the mounting frame 420 can also be set as a rectangular frame. The first rotating connection seat 100 is arranged inside the mounting frame 420 and is rotationally connected to the mounting frame 420. The second rotating connection seat 200 is installed inside the mounting frame 420 through a linear drive device and is rotationally connected to the drive end of the linear drive device. The rotation axes of the first rotating connection seat 100 and the second rotating connection seat 200 are collinear. The linear drive device is slidably connected to the mounting frame 420, and the sliding direction is parallel to the rotation axes of the first rotating connection seat 100 and the second rotating connection seat 200.

[0056] Specifically, the first rotating connection seat 100 is arranged at the inner bottom of the rectangular frame and is located at the middle position of the rectangular frame along the left-right direction. The rotation axis of the first rotating connection seat 100 is along the vertical direction. The linear drive device is arranged at the top of the rectangular frame, and the drive end of the linear drive device is located inside the rectangular frame. The moving end of the linear drive device moves along the vertical direction. The second rotating connection seat 200 is arranged at the moving end of the linear drive device, and the second rotating connection seat 200 is located at the middle position of the rectangular frame along the left-right direction. The rotation axis of the second rotating connection seat 200 is along the vertical direction.

[0057] Of course, the first rotating connection seat 100 and the second rotating connection seat 200 can also be respectively arranged on the left and right sides of the rectangular frame, and the rotation axis is along the left and right direction.

[0058] The base is arranged at the bottom of the installation frame 420 and is used for supporting on the ground to support the installation frame 420 at an appropriate height.

[0059] In some embodiments of the present utility model, the base may include a chassis 410 and a lifting support rod. The chassis 410 is used to increase the support area with the ground to improve stability. The bottom of the lifting support rod is connected to the chassis 410, and the top of the lifting support rod is connected to the bottom of the installation frame 420. The lifting support rod can change the height of the installation frame 420 by telescoping to adapt to the use of subjects with different heights.

[0060] In some embodiments of the present utility model, the structures of the first rotating connection seat 100 and the second rotating connection seat 200 are the same. Both the first rotating connection seat 100 and the second rotating connection seat 200 include a connection block 510. A slot 520 is arranged on one side of the connection block 510, and a rotating shaft 530 is arranged on the other side.

[0061] Taking the first rotating connection seat 100 as an example, the connection block 510 can be a cuboid-shaped block structure. A slot 520 extending downward is arranged at the top of the connection block 510. The slot 520 can be a rectangular slot. A rectangular plug 310 extending downward is arranged at the middle position of the bottom of the visual acuity chart 300, so that the visual acuity chart 300 can be plugged and connected with the connection block 510, and the relative rotation between the two can be restricted.

[0062] A rotating shaft 530 extending downward is arranged at the bottom of the connection block 510. A first shaft hole 421 is arranged at the middle position of the inner bottom of the installation frame 420. The rotating shaft 530 is inserted into the first shaft hole 421, and a bearing is arranged between the rotating shaft 530 and the inner wall of the first shaft hole 421 to realize the rotational connection between the connection block 510 and the installation frame 420, and at the same time, the relative movement of the connection block 510 relative to the installation frame 420 in the vertical direction can also be restricted.

[0063] In some embodiments of the present utility model, the linear driving device includes a sliding rod 610, a handle 620, a mounting block 630 and a reset member.

[0064] Two sliding rods 610 can be arranged. The two sliding rods 610 are distributed along the left and right direction of the installation frame 420 and extend along the vertical direction. The two sliding rods 610 penetrate the installation frame 420 from top to bottom, and the symmetry line of the axes of the two sliding rods 610 passes through the rotation axes of the first rotating connection seat 100 and the second rotating connection seat 200.

[0065] The handle 620 is arranged on the part of the sliding rod 610 above the mounting frame 420, and the handle 620 is used to drive the sliding rod 610 to slide relative to the mounting frame 420.

[0066] The mounting block 630 is arranged at one end of the sliding rod 610 inside the mounting frame 420, and a second shaft hole 631 extending upward is arranged on the bottom surface of the mounting block 630. The rotating shaft 530 at the top of the connecting block 510 serving as the second rotating connection seat 200 can be inserted into the second shaft hole 631, and a bearing is arranged between the rotating shaft 530 and the second shaft hole 631 to realize the rotating connection between the second rotating connection seat 200 and the mounting block 630. At the same time, when the two are connected by a bearing, the relative movement of the mounting block 630 and the connecting block 510 along the axis can also be restricted. When the handle 620 drives the mounting block 630 to move through the sliding rod 610, the mounting block 630 drives the connecting block 510 to move together through the bearing, so as to realize the effect of moving the connecting block 510 to the first position or the second position.

[0067] The reset member is arranged between the top of the mounting block 630 and the mounting frame 420. For example, the reset member can be a spring 640. The spring 640 is sleeved on the outside of the sliding rod 610, and one end is in contact with the top of the mounting block 630, and the other end is in contact with the inner top end of the mounting frame 420.

[0068] When the handle 620 is pulled upward, and then the connecting block 510 moves to the second position, the spring 640 is compressed and stores energy. When the handle 620 is released, the spring 640 restores deformation and releases elastic force, pushing the connecting block 510 to automatically return to the first position.

[0069] In some embodiments of the present invention, the limiting component includes a first linear telescopic mechanism and a blocking member.

[0070] The first linear telescopic mechanism can be a lead screw nut mechanism, including a sliding sleeve 711, a first lead screw 712, a rotating handle 713 and a slider 714. The sliding sleeve 711 penetrates through the mounting frame 420 and is arranged at a position near the end of the bottom of the mounting block 630. The sliding sleeve 711 can be a rectangular tube structure with a hollow interior. The slider 714 is slidably arranged in the sliding sleeve 711, and the slider 714 is also a rectangular block. The outer side wall of the slider 714 is in contact with the inner wall of the sliding sleeve 711. In this way, the slider 714 can only move in the vertical direction under the constraint of the sliding sleeve 711 without rotating.

[0071] The bottom end of the first lead screw 712 is rotatably connected to the bottom surface of the sliding sleeve 711, the other end of the first lead screw 712 is threadedly connected to the slider 714, and the rotating handle 713 is arranged at the bottom end of the first lead screw 712. When the rotating handle 713 drives the first lead screw 712 to rotate, under the action of the thread between the first lead screw 712 and the slider 714, the slider 714 is determined to move in the vertical direction.

[0072] The blocking member can be a blocking rod 720. The blocking rod 720 penetrates through the top surface of the sliding sleeve 711, and the bottom end of the blocking rod 720 is connected to the slider 714. The other end of the blocking rod 720 extends upward, and the blocking rod 720 moves synchronously with the slider 714.

[0073] A limiting hole 320 is provided at a position corresponding to the blocking rod 720 at the bottom of the eye chart 300. When the blocking rod 720 extends upward, the top end of the blocking rod 720 can penetrate into the limiting hole 320 to limit the rotation of the eye chart 300. When the blocking rod 720 retracts downward, the blocking rod 720 is separated from the limiting hole 320, and the eye chart 300 can rotate freely.

[0074] Of course, the first linear expansion mechanism can also be an electric push rod or a structure the same as the above-mentioned linear driving device.

[0075] In some embodiments of the present utility model, the lifting support rod includes a fixed rod 431, a moving rod 432, and a second linear expansion mechanism.

[0076] The bottom end of the fixed rod 431 is connected to the chassis 410. The fixed rod 431 is hollow inside, and a first limiting groove 443 extending in the vertical direction is provided inside the fixed rod 431. The moving rod 432 is nested inside the fixed rod 431, and a first limiting block 444 cooperating with the first limiting groove 443 is provided on the outer side of the moving rod 432. When the moving rod 432 slides relative to the fixed rod 431, the first limiting block 444 and the first limiting groove 443 are used to limit the moving rod 432 to move only in the vertical direction without rotation.

[0077] The second linear expansion mechanism is a lead screw nut mechanism. A motor 441 is provided at the inner bottom of the fixed rod 431. The driving shaft of the motor 441 extends upward, and a second lead screw 442 is connected to the top end of the driving shaft. The second lead screw 442 extends in the vertical direction. A threaded hole 445 extending along the axis of the moving rod 432 is provided inside the moving rod 432, and the second lead screw 442 is screwed into the threaded hole 445.

[0078] When the motor 441 drives the second lead screw 442 to rotate, the second lead screw 442 interacts with the threaded hole 445, thereby driving the moving rod 432 to move up and down to change the height of the mounting frame 420.

[0079] An embodiment of the present utility model further provides a vision detection device, including an eye chart 300 and the anti-cheating eye chart fixing device as described above. The eye chart 300 is arranged between the first rotating connection seat 100 and the second rotating connection seat 200 of the anti-cheating eye chart fixing device, and thus has the same advantages as described above.

[0080] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than limiting them; although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application, and they should all be covered within the scope of the claims and the description of the present application. In particular, as long as there is no structural conflict, the technical features mentioned in each embodiment can be combined in any way. The present application is not limited to the specific embodiments disclosed in the text, but includes all technical solutions that fall within the scope of the claims.

Claims

1. An anti-cheating eye chart fixing device, characterized in that: include: Frame; A first rotating connection seat (100), one end of the first rotating connection seat (100) is rotatably connected to the frame, the other end of the first rotating connection seat (100) is used for plugging and connecting with the eye chart (300), and the first rotating connection seat (100) is non-rotatably connected to the eye chart (300); A linear drive device, the linear drive device is connected to the frame and is located on a side opposite to the first rotating connection seat (100), and the movement direction of the moving end of the linear drive device is parallel to the rotation axis of the first rotating connection seat (100); A second rotating connection seat (200), one end of the second rotating connection seat (200) is rotatably connected to the movable end of the linear drive device, the other end of the second rotating connection seat (200) is used for plugging and connecting with the eye chart (300), and the second rotating connection seat (200) is non-rotatably connected to the eye chart (300), the rotation axes of the second rotating connection seat (200) and the first rotating connection seat (100) are colinear, and the second rotating connection seat (200) is used to move with the linear drive device in a direction close to or away from the first rotating connection seat (100).

2. The anti-cheating eye chart fixing device according to claim 1, characterized in that: It also includes a limiting component, which is arranged on the frame, and a portion of the limiting component close to the eye chart (300) is used to contact or separate from the eye chart (300). When the limiting component contacts the eye chart (300), the limiting component is used to limit the rotation of the eye chart (300).

3. The anti-cheating eye chart fixing device according to claim 1, characterized in that: The frame comprises: Base; The mounting frame (420) is arranged on the top of the base, and the first rotating connection seat (100) and the linear driving device are arranged on two opposite sides of the mounting frame (420).

4. The anti-cheating eye chart fixing device according to claim 3 is characterized in that: The first rotating connection seat (100) is arranged at the inner bottom of the installation frame (420), the linear drive device is arranged at the top of the installation frame (420), the second rotating connection seat (200) is arranged at the bottom of the linear drive device, the rotation axes of the first rotating connection seat (100) and the second rotating connection seat (200) are along the vertical direction, and the rotation axes of the two are collinear, and the movement direction of the linear drive device is along the vertical direction; Alternatively, the first rotating connection seat (100) and the linear drive device are respectively arranged on the left and right sides of the inner side of the installation frame (420), and the second rotating connection seat (200) is arranged at one end of the linear drive device close to the first rotating connection seat (100). The rotation axes of the first rotating connection seat (100) and the second rotating connection seat (200) are along the left-right direction, and the rotation axes of the two are collinear, and the movement direction of the linear drive device is along the left-right direction.

5. The anti-cheating eye chart fixing device according to claim 3, characterized in that: The base comprises a chassis (410) and a lifting support rod, wherein the lifting support rod is arranged between the chassis (410) and the installation frame (420).

6. The anti-cheating eye chart fixing device according to claim 3, characterized in that: The first rotating connection seat (100) and the second rotating connection seat (200) both comprise a connection block (510), on which a slot (520) and a rotating shaft (530) are provided, wherein the slot (520) and the rotating shaft (530) are provided on opposite sides of the connection block (510), wherein the slot (520) and the rotating shaft (530) are provided on opposite sides of the connection block (510), wherein the slot (520) is non-rotatably connected to a plug (310) at a corresponding position on the eye chart (300), wherein the rotating shaft (530) of the first rotating connection seat (100) is rotationally connected to the mounting frame (420) via a bearing, and wherein the rotating shaft (530) of the second rotating connection seat (200) is rotationally connected to a driving end of the linear drive device.

7. The anti-cheating eye chart fixing device according to claim 6, characterized in that: The linear drive device comprises: A sliding rod (610), the sliding rod (610) passing through both inner and outer sides of the installation frame (420), and the sliding rod (610) is slidably connected to the installation frame (420); A handle (620), the handle (620) being arranged at one end of the sliding rod (610) located outside the installation frame (420); A mounting block (630), wherein the mounting block (630) is arranged at one end of the sliding rod (610) located on the inner side of the mounting frame (420), and a second shaft hole (631) is arranged on a side of the mounting block (630) away from the handle (620), and the rotating shaft (530) of the second rotating connecting seat (200) is rotatably connected to the second shaft hole (631) via a bearing; a reset member, the reset member being arranged between the mounting block (630) and the mounting frame (420); When the handle (620) drives the sliding rod (610) to move toward the outside of the installation frame (420), the reset member accumulates force, and when the handle (620) is released, the reset member releases the elastic force to drive the installation block (630) to reset.

8. The anti-cheating eye chart fixing device according to claim 2, characterized in that: The limiting assembly comprises a first linear telescopic mechanism and a blocking member, wherein the first linear telescopic mechanism is fixedly connected to the frame, the telescopic end of the first linear telescopic mechanism moves in a direction approaching or away from the eye chart (300), and the blocking member is arranged at the telescopic end of the first linear telescopic mechanism, and when the telescopic end of the first linear telescopic mechanism drives the blocking member to move to a position in contact with the eye chart (300), the blocking member limits the rotation of the eye chart (300).

9. The anti-cheating eye chart fixing device according to claim 5, characterized in that: The lifting support rod comprises a fixed rod (431), a moving rod (432) and a second linear telescopic mechanism, wherein the bottom end of the fixed rod (431) is connected to the chassis (410), the moving rod (432) is nested and connected to the top of the fixed rod (431), and the second linear telescopic mechanism is arranged between the fixed rod (431) and the moving rod (432).

10. A vision detection device, characterized in that: It comprises an eye chart (300) and an anti-cheating eye chart fixing device as claimed in any one of claims 1 to 9, wherein the eye chart (300) is arranged between a first rotating connection seat (100) and a second rotating connection seat (200) of the anti-cheating eye chart fixing device.

Images