Printed circuit board detection method

Abstract

The invention discloses a printed circuit board detection method. The printed circuit board detection method comprises an image capturing step, a laser ranging step, an image detection step and a thickness detection step. The processing assembly obtains the number of pixels of a printed circuit board and a measured thickness through an image capturing step and a laser ranging step. When the processing assembly compares the number of pixels of the printed circuit board to be larger than a threshold value and compares the measured thickness to be larger than a preset thickness through the image detection step and the thickness detection step, the processing assembly sends out lamination information.

Description

Technical Field

[0001] The present invention relates to a detection method, and in particular to a detection method for printed circuit boards. Background Art

[0002] In the production and processing process of printed circuit boards, existing detection devices need to use a printed circuit board loading machine to place printed circuit boards on a production line or other workstations. During operation, the printed circuit board loading machine may output two printed circuit boards stacked together due to working errors, which will affect subsequent normal production. Therefore, a stacked board detection device for printed circuit boards is often provided downstream of the printed circuit board loading machine.

[0003] Therefore, the inventor believes that the above defects can be improved. After painstaking research and the application of scientific principles, the inventor finally proposed the present invention with a reasonable design and effective improvement of the above defects. Summary of the Invention

[0004] An embodiment of the present invention provides a detection method for printed circuit boards, which can effectively improve the possible defects of existing printed circuit board detection methods.

[0005] One embodiment of the present invention discloses a detection method for printed circuit boards, and the steps include: an imaging step: when a working board carries at least one printed circuit board, obtaining an image of at least one printed circuit board through an imaging component; a laser ranging step: when the working board carries at least one printed circuit board, emitting an emission light and receiving a reflected light to at least one printed circuit board through a laser ranging sensor; an image detection step: configuring a processing component to obtain a printed circuit board image through the imaging component, and calculating the number of pixels of the printed circuit board based on the contour of the printed circuit board to obtain a printed circuit board pixel number; wherein, the processing component compares whether the printed circuit board pixel number is greater than a threshold; and a thickness detection step: configuring the processing component to calculate the time between the emission of the emission light and the reception of the reflected light by the laser ranging sensor to obtain a measured thickness; wherein, the processing component compares whether the measured thickness is greater than a preset thickness; wherein, when the processing component compares that the printed circuit board pixel number is greater than the threshold and the measured thickness is greater than the preset thickness, the processing component issues a stacked board message to confirm that stacking has occurred.

[0006] Optionally, in the image detection step, the processing component segments the printed circuit board image according to the contour of the printed circuit board to generate a printed circuit board contour image, and the processing component calculates the pixels of the printed circuit board contour image to obtain the printed circuit board pixel number.

[0007] Optionally, in the thickness detection step, the processing component calculates a sensing distance based on the time difference between an emission time of the emitted light and a reception time of the reflected light, and calculates the measured thickness based on the distance between the laser distance sensor and the work plate and the sensing distance.

[0008] Optionally, the printed circuit board detection method further includes a startup step before the imaging step. Startup step: Configure a color mark sensor to sense a trigger point of the work plate to drive the imaging component and the laser distance sensor to operate.

[0009] Optionally, the color mark sensor senses the trigger point of the work plate to drive the imaging component and the laser distance sensor to operate synchronously.

[0010] Optionally, when the number of at least one printed circuit board is multiple, the sizes of each printed circuit board are the same.

[0011] Optionally, in the imaging step and the laser ranging step, configure an adjustment module to adjust the positions of the imaging component and the laser distance sensor; wherein, the adjustment module includes a lateral adjustment component and a longitudinal adjustment component, and the lateral adjustment component is vertically arranged on the longitudinal adjustment component; wherein, the lateral adjustment component can move along a lateral direction perpendicular to a height direction to make the imaging component and the laser distance sensor located above the work plate, and the longitudinal adjustment component can move along the height direction to determine the distance between the laser distance sensor and the work plate.

[0012] Optionally, the imaging component and the laser distance sensor are arranged at the end of the lateral adjustment component, and the lateral adjustment component can drive the imaging component and the laser distance sensor to move back and forth along the lateral direction.

[0013] Optionally, the longitudinal adjustment component includes: a fixed block; a guide rod fixedly connected to the fixed block, the guide rod having a thread groove arranged along the height direction; a threaded rod having two ends located on opposite sides, one end of the threaded rod meshing with the thread groove; a sliding sleeve having a through hole; wherein, the other end of the threaded rod rotatably passes through the through hole; a sliding rod in a hollow shape, the inner wall of the sliding rod fixedly connected to the sliding sleeve, and the sliding rod slidably sleeved on the guide rod; a rotating rod having an external thread, the rotating rod rotatably passing through the sliding rod and spaced from the other end of the threaded rod; a driving bevel gear meshing with the external thread of the rotating rod; and a driven bevel gear meshing with the driving bevel gear and the threaded rod; wherein, when the rotating rod rotates to drive the driving bevel gear to rotate, the driven bevel gear drives the threaded rod to rotate synchronously, so that the sliding sleeve and the sliding rod can move up and down along the height direction.

[0014] In summary, the printed circuit board detection method disclosed in the embodiments of the present invention ensures that there is indeed a phenomenon of overlapping printed circuit boards by "when the processing component compares that the number of pixels of the printed circuit board is greater than the threshold and the measured thickness is greater than the preset thickness, the processing component issues an overlapping board message to confirm that there is an overlapping board", thereby increasing the detection accuracy of the printed circuit board.

[0015] To further understand the features and technical content of the present invention, please refer to the following detailed description and drawings of the present invention. However, these descriptions and drawings are only used to illustrate the present invention and do not impose any limitation on the protection scope of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic three-dimensional structure diagram of the printed circuit board detection device according to the embodiment of the present invention.

[0017] Figure 2 It is a schematic flowchart of the printed circuit board detection method according to the embodiment of the present invention.

[0018] Figure 3 It is a schematic cross-sectional view of the longitudinal adjustment component according to the embodiment of the present invention.

[0019] Figure 4 It is a schematic three-dimensional structure diagram of the mounting component according to the embodiment of the present invention.

[0020] Figure 5 It is a circuit block diagram of the printed circuit board detection device according to the embodiment of the present invention.

[0021] Figure 6 It is a schematic diagram of the processing component dividing the printed circuit board image and calculating that the number of pixels of the printed circuit board does not exceed the threshold according to the embodiment of the present invention.

[0022] Figure 7 It is a schematic diagram of the processing component dividing the printed circuit board image and calculating that the number of pixels of the printed circuit board exceeds the threshold according to the embodiment of the present invention.

[0023] Figure 8 It is a schematic diagram of the printed circuit board detection device detecting the thickness of at least one printed circuit board according to the embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0024] The following is an implementation manner of the "printed circuit board detection method" disclosed in the present invention through specific specific embodiments. Those skilled in the art can understand the advantages and effects of the present invention from the content disclosed in this specification. The present invention can be implemented or applied through other different specific embodiments, and various details in this specification can also be modified and changed based on different viewpoints and applications without departing from the concept of the present invention. Additionally, the drawings of the present invention are only simple schematic illustrations and are not drawn according to actual dimensions, and this is stated in advance. The following implementation manners will further detail the related technical content of the present invention, but the disclosed content is not used to limit the protection scope of the present invention.

[0025] It should be understood that although terms such as "first", "second", "third", etc. may be used herein to describe various components or signals, these components or signals should not be limited by these terms. These terms are mainly used to distinguish one component from another component, or one signal from another signal. Additionally, the term "or" used herein should, depending on the actual situation, possibly include any one or a combination of more of the associated listed items.

[0026] Please refer to Figures 1 to 8 shown, which is an embodiment of the present invention. The embodiment of the present invention discloses a printed circuit board detection method S100 and a printed circuit board detection device 100, and preferably, the printed circuit board detection method S100 is implemented by the printed circuit board detection device 100, but the present invention is not limited thereto. Among them, the printed circuit board detection method S100 in this embodiment includes (or is implemented in sequence) a preparation step S101, a startup step S103, an imaging step S105, a laser ranging step S107, an image detection step S109, and a thickness detection step S110.

[0027] To facilitate understanding of this embodiment, the respective contents of the preparation step S101, the startup step S103, the imaging step S105, the laser ranging step S107, the image detection step S109, and the thickness detection step S110 will be described separately below, and the structure of the printed circuit board detection device 100 will be introduced as appropriate, but the present invention is not limited thereto. For example, in other embodiments not shown in the present invention, any step included in the printed circuit board detection method S100, and the respective component structures of the printed circuit board detection device 100 can be adjusted, changed, or omitted according to design requirements (for example: the startup step S103 can be omitted or replaced by other steps); or, the printed circuit board detection method S100 can be implemented by a device different from the printed circuit board detection device 100.

[0028] The preparation step S101: As Figure 1With Figure 2 As shown in Figure 2 , the printed circuit board detection device 100 is provided. In this embodiment, it includes a detection body 1, an imaging component 2 spaced apart from the detection body 1, a laser distance sensor 3 spaced apart from the imaging component 2, and a processing component 4 electrically coupled to the imaging component 2 and the laser distance sensor 3.

[0029] The detection body 1 includes a working board 11 and an adjustment module 12 spaced apart from the working board 11. The working board 11 is used to carry at least one printed circuit board PCB. It should be noted that, in principle, the working board 11 carries one printed circuit board PCB. However, sometimes due to working errors during the operation of the printed circuit board loading machine, two stacked printed circuit boards PCB may be output onto the working board 11. Therefore, the printed circuit board detection device 100 and the printed circuit board detection method S100 of this embodiment can detect the phenomenon of stacked boards where the number of at least one printed circuit board PCB on the working board 11 exceeds 2.

[0030] The adjustment module 12 has a mounting component 121. The mounting component 121 is spaced apart above the working board 11 along a height direction H. That is, the adjustment module 12 can adjust the position of the mounting component 121 so that the mounting component 121 can be located above the working board 11. Specifically, the adjustment module 12 includes a horizontal adjustment component 122 and a vertical adjustment component 123 connected to the horizontal adjustment component 122. The horizontal adjustment component 122 is vertically disposed on the vertical adjustment component 123. The horizontal adjustment component 122 has two opposite ends. One end of the horizontal adjustment component 122 is provided with the mounting component 121, and the other end of the horizontal adjustment component 122 is connected to the vertical adjustment component 123. The horizontal adjustment component 122 can drive the mounting component 121 to move along a horizontal direction C perpendicular to the height direction H so that the mounting component 121 can be located above the working board 11.

[0031] The vertical adjustment component 123 has two opposite ends. One end of the vertical adjustment component 123 is fixed to the platform of the detection body 1, and the other end of the vertical adjustment component 123 fixes the other end of the horizontal adjustment component 122. The vertical adjustment component 123 can drive the horizontal adjustment component 122 to move along the height direction H to determine the distance between the mounting component 121 (i.e., the imaging component 2 and the laser distance sensor 3) and the working board 11.

[0032] Specifically, as Figure 3As shown, it should be noted that since the internal adjustment structures of the longitudinal adjustment component 123 and the transverse adjustment component 122 are the same as each other. The following content of this embodiment mainly describes the internal adjustment structure of the longitudinal adjustment component 123, and the internal adjustment structure of the transverse adjustment component 122 will not be elaborated herein.

[0033] The longitudinal adjustment component 123 includes a fixed block 1231, a guide rod 1232 fixedly connected to the fixed block 1231, a threaded rod 1233 connected to the guide rod 1232, a sliding sleeve 1234 connected to the threaded rod 1233, a sliding rod 1235 connected to the sliding sleeve, a rotating rod 1236 rotatably passing through the sliding rod 1235, a driving bevel gear 1237 connected to the rotating rod 1236, and a driven bevel gear 1238 connected to the driving bevel gear 1237.

[0034] The guide rod 1232 is fixedly connected to the fixed block 1231, and the guide rod 1232 has a threaded groove (not shown in the figure) arranged along the height direction H. The threaded rod 1233 has two ends located on the opposite sides, and one end of the threaded rod 1233 is engaged with the threaded groove. When the threaded rod 1233 rotates, the threaded rod 1233 can move away from the guide rod 1232 or move closer to the guide rod 1232.

[0035] The sliding sleeve 1234 has a through hole TH. The other end of the threaded rod 1233 rotatably passes through the through hole TH so that the sliding sleeve 1234 does not rotate with the rotation of the threaded rod 1233. The sliding rod 1235 is hollow, the inner wall of the sliding rod 1235 is fixedly connected to the sliding sleeve 1234, and the sliding rod 1235 is slidably sleeved on the guide rod 1232. The rotating rod 1236 has an external thread ET.

[0036] The rotating rod 1236 is rotatably disposed in the sliding rod 1235, and the rotating rod 1236 is spaced from the other end of the threaded rod 1233. In this embodiment, the rotating rod 1236 has two ends located on the opposite sides, one end of the rotating rod 1236 passes through one side of the sliding rod 1235, and the other end of the rotating rod 1236 is connected to a nut 1239. The rotation of the nut 1239 can drive the rotation of the rotating rod 1236.

[0037] The active bevel gear 1237 meshes with the external thread ET of the rotating rod 1236. The driven bevel gear 1238 meshes with the active bevel gear 1237 and the threaded rod 1233. In this embodiment, the driven bevel gear 1238 is vertically arranged with respect to the active bevel gear 1237, and the driven bevel gear 1238 is vertically arranged with respect to the threaded rod 1233, while the threaded rod 1233 is horizontally arranged with respect to the active bevel gear 1237.

[0038] As described above, when the rotating rod 1236 is rotated to drive the active bevel gear 1237 to rotate, the driven bevel gear 1238 is driven to rotate, driving the threaded rod 1233 to rotate, so that the sliding sleeve 1234 and the sliding rod 1235 can move up and down along the height direction H, thereby achieving the purpose of longitudinal adjustment.

[0039] As Figure 1 , Figure 4 and Figure 5 shown, the imaging component 2 is arranged on the mounting component 121. Among them, the imaging component 2 can face at least one printed circuit board PCB to obtain an image of the printed circuit board PCB. The laser distance sensor 3 is arranged on the mounting component 121, and the laser distance sensor 3 and the imaging component 2 are spaced apart from each other. The laser distance sensor 3 faces at least one printed circuit board PCB to emit an emission light beam and receive a reflected light beam.

[0040] The processing component 4 is arranged in the detection body 1, and the processing component 4 is electrically coupled to the imaging component 2 and the laser distance sensor 3. The processing component 4 can control the operation of the imaging component 2 and the laser distance sensor 3. That is to say, the processing component 4 can control the imaging component 2 to acquire an image. The processing component 4 can control the laser distance sensor 3 to emit the emission light beam and receive the reflected light beam.

[0041] In addition, as Figure 4 shown, the printed circuit board detection device 100 further includes a color mark sensor 5. The color mark sensor 5 is arranged on the mounting component 121, and the color mark sensor 5 is spaced apart from the imaging component 2 and the laser distance sensor 3. The color mark sensor 5 senses a trigger point (not shown in the figure) of the work plate 11 to drive the imaging component 2 and the laser distance sensor 3 to operate.

[0042] The above is the description of the preparation step S101 (or the printed circuit board detection device 100) in this embodiment, and the printed circuit board detection method S100 will be implemented in combination with the printed circuit board detection device 100 to achieve the startup step S103, the imaging step S105, the laser ranging step S107, the image detection step S109, and the thickness detection step S110 hereinafter; however, in other embodiments not shown in the present invention, the startup step S103, the imaging step S105, the laser ranging step S107, the image detection step S109, and the thickness detection step S110 can also be implemented by devices different from the printed circuit board detection device 100, and the present invention is not limited thereto.

[0043] The startup step S103: The color sensor 5 reaches the trigger point of the work board 11 to drive the imaging component 2 and the laser ranging sensor 3 to operate.

[0044] The imaging step S105: When the work board 11 carrying at least one printed circuit board PCB is located below the mounting component 121, the imaging component 2 acquires an image of the printed circuit board PCB. In practice, the work board 11 is located on the production line. When the work board 11 carrying at least one printed circuit board PCB is moved by the production line to below the imaging component 2, the imaging component 2 acquires an image of the printed circuit board PCB and generates a printed circuit board image.

[0045] The laser ranging step S107: When the work board 11 carrying at least one printed circuit board PCB is located below the mounting component 121, the laser ranging sensor 3 emits the emission light to and receives the reflected light from at least one printed circuit board PCB.

[0046] The image detection step S109: The processing component 4 obtains the printed circuit board image through the imaging component 2, and the processing component 4 calculates the number of pixels of the printed circuit board image based on the contour of the printed circuit board to obtain a printed circuit board pixel number. Among them, the processing component 4 compares whether the printed circuit board pixel number is greater than a threshold value to preliminarily detect whether there is a phenomenon of overlapping printed circuit boards PCB on the work board 11.

[0047] In this embodiment, the processing component 4 segments the printed circuit board image according to the contour of the printed circuit board PCB to generate a printed circuit board contour image, and the processing component 4 calculates the pixels of the printed circuit board contour image to obtain the printed circuit board pixel number, as Figure 6As shown, the processing component 4 compares that the number of pixels of the printed circuit board is approximately equal to the threshold. That is, when the number of pixels of the printed circuit board is approximately equal to the area size of a printed circuit board, it is preliminarily detected that there is no phenomenon of overlapping printed circuit boards (PCBs) on the working board 11.

[0048] On the contrary, as Figure 7 shown, the processing component 4 compares that the number of pixels of the printed circuit board is greater than the threshold. That is, when the number of pixels of the printed circuit board is greater than the area size of a printed circuit board, it is preliminarily detected that there is an overlapping phenomenon of the printed circuit board (PCB) on the working board 11.

[0049] The thickness detection step S110: The processing component 4 calculates the time between the emission of the emission light ray and the reception of the reflected light ray by the laser distance sensor 3 to obtain a measured thickness. The processing component 4 compares whether the measured thickness is greater than a preset thickness to determine whether there is an overlapping phenomenon of at least one printed circuit board (PCB) on the working board 11.

[0050] It should be noted that the processing component 4 calculates a sensing distance d based on the time difference between the emission time of the emission light ray and the reception time of the reflected light ray (as Figure 8 shown), and the processing component 4 calculates the measured thickness based on the distance between the laser distance sensor 3 and the working board 11 and the sensing distance.

[0051] Specifically, as Figure 8 shown, the distance between the laser distance sensor 3 and the working board 11 is a working height h, the preset thickness Δh is the thickness of a single printed circuit board (PCB), and the sensing distance d is the distance between the laser distance sensor 3 and the printed circuit board (PCB) calculated by the processing component 4 through the laser distance sensor 3. When the processing component 4 determines that the working height h minus the sensing distance d is greater than the preset thickness Δh, it is determined that there is an overlapping phenomenon of at least one printed circuit board (PCB) on the working board 11. The judgment formula is as follows:

[0052] ---------------- (1)

[0053] It should be noted that the principle of the processing component 4 calculating the sensing distance through the laser distance sensor 3 is as follows. The laser distance sensor 3 emits the emission light ray, and the frequency of the emission light ray changes linearly with time t. Its frequency modulation law is shown in the following formula (2):

[0054] ----------(2)

[0055] Wherein, is the initial frequency; k is the frequency modulation rate (i.e., the frequency change rate).

[0056] After the emitted light ray encounters the printed circuit board PCB, part of the light is reflected to generate the reflected light ray, which is received by the laser distance sensor 3. Since the laser propagation requires time (i.e., the round-trip delay), the frequency of the reflected light ray is different from the frequency of the current emitted light ray. Inside the laser distance sensor 3, the reflected light ray and the reference light are mixed (i.e., superimposed). After mixing, a low-frequency signal is generated, and its frequency is ∆𝑓:

[0057] ---------------(3)

[0058] Wherein, is the light propagation time, The formula of is as follows:

[0059] -------------------(4)

[0060] Wherein, d is the distance between the printed circuit board PCB and the laser distance sensor 3; c is the speed of light.

[0061] As described above, through formula (3) and formula (4), the distance between the printed circuit board PCB and the laser distance sensor 3 can be obtained, as shown in the following formula:

[0062] -----------------(5)

[0063] When the processing component 4 compares that the number of pixels of the printed circuit board is greater than the threshold and compares that the measured thickness is greater than the preset thickness △h, the processing component 4 issues a stacking information to confirm that stacking has occurred.

[0064] It should be noted that the present invention is not limited to the printed circuit board detection method S100 performing the image detection step S109 first and then performing the thickness detection step S110. For example, the image detection step S109 and the thickness detection step S110 can be performed synchronously, or the processing component thickness detection step S110 performs the thickness detection step S110 first and then performs the image detection step.

[0065] [Technical effects of the embodiments of the present invention]

[0066] In summary, a printed circuit board detection device disclosed in an embodiment of the present invention ensures that a printed circuit board actually has a stacking phenomenon and thereby improves the detection accuracy of the printed circuit board by "when the processing component compares that the number of pixels of the printed circuit board is greater than a threshold value and the measured thickness is greater than a preset thickness, the processing component issues stacking information to confirm that stacking has occurred".

[0067] The content disclosed above is only a preferred and feasible embodiment of the present invention, and does not limit the patent scope of the present invention. Therefore, all equivalent technical changes made by using the content of the specification and drawings of the present invention are included in the patent scope of the present invention.

Claims

1. A printed circuit board detection method, characterized in that, The steps of the printed circuit board detection method include: An imaging step: When a work board carries at least one printed circuit board, an image of at least one of the printed circuit boards is obtained through an imaging component; A laser ranging step: When the work board carries at least one of the printed circuit boards, a laser ranging sensor emits an emission light ray and receives a reflected light ray for at least one of the printed circuit boards; An image detection step: A processing component is configured to obtain an image of a printed circuit board through the imaging component, and calculate the number of pixels of the printed circuit board based on the contour of the printed circuit board to obtain the number of pixels of a printed circuit board; wherein, the processing component compares whether the number of pixels of the printed circuit board is greater than a threshold value; and A thickness detection step: The processing component is configured to calculate the time between the emission of the emission light ray and the reception of the reflected light ray by the laser ranging sensor to obtain a measured thickness; wherein, the processing component compares whether the measured thickness is greater than a preset thickness; Wherein, when the processing component compares that the number of pixels of the printed circuit board is greater than the threshold value and compares that the measured thickness is greater than the preset thickness, the processing component issues a board stacking information to confirm that board stacking has occurred.

2. The printed circuit board detection method according to claim 1, wherein In the image detection step, the processing component segments the printed circuit board image based on the contour of the printed circuit board to generate a printed circuit board contour image, and the processing component calculates the pixels of the printed circuit board contour image to obtain the number of pixels of the printed circuit board.

3. The printed circuit board detection method according to claim 1, wherein In the thickness detection step, the processing component calculates a sensed distance based on the time difference between the emission time of the emission light ray and the reception time of the reflected light ray, and calculates the measured thickness based on the distance between the laser ranging sensor and the work board and the sensed distance.

4. The printed circuit board detection method according to claim 1, wherein Before the imaging step, the printed circuit board detection method further includes a startup step, and the startup step: A color mark sensor is configured to sense a trigger point of the work board to drive the imaging component and the laser ranging sensor to operate.

5. The printed circuit board detection method according to claim 4, wherein, The color mark sensor senses the trigger point of the work board to drive the imaging component and the laser ranging sensor to operate synchronously.

6. The printed circuit board detection method according to claim 1, characterized in that, When the number of at least one of the printed circuit boards is multiple, the sizes of each of the printed circuit boards are the same.

7. The printed circuit board detection method according to claim 1, characterized in that In the imaging step and the laser ranging step, an adjustment module is configured to adjust the positions of the imaging component and the laser ranging sensor; wherein, the adjustment module includes a horizontal adjustment component and a vertical adjustment component, and the horizontal adjustment component is vertically disposed on the vertical adjustment component; wherein, the horizontal adjustment component can move along a horizontal direction perpendicular to a height direction to enable the imaging component and the laser ranging sensor to be located above the work board, and the vertical adjustment component can move along the height direction to determine the distance between the laser ranging sensor and the work board.

8. The printed circuit board detection method according to claim 7, wherein The imaging component and the laser distance sensor are arranged at the end of the lateral adjustment component, and the lateral adjustment component can drive the imaging component and the laser distance sensor to move back and forth along the lateral direction.

9. The printed circuit board detection method according to claim 7, characterized in that, The longitudinal adjustment component includes: A fixed block; A guide rod fixedly connected to the fixed block, and the guide rod has a thread groove arranged along the height direction; A threaded rod having two ends located on opposite sides, and one end of the threaded rod meshes with the thread groove; A sliding sleeve having a through hole; wherein, the other end of the threaded rod rotatably passes through the through hole; A sliding rod which is hollow, the inner wall of the sliding rod is fixedly connected to the sliding sleeve, and the sliding rod slidably sleeved on the guide rod; A rotating rod having an external thread, the rotating rod rotatably passes through the sliding rod and is spaced from the other end of the threaded rod; A driving bevel gear meshing with the external thread of the rotating rod; and A driven bevel gear meshing with the driving bevel gear and the threaded rod; Wherein, when the rotating rod rotates to drive the driving bevel gear to rotate, the driven bevel gear is linked to drive the threaded rod to rotate, so that the sliding sleeve and the sliding rod can move up and down along the height direction.

Images