A SPM workbench support frame capable of automatically adjusting the levelness

Abstract

The invention relates to an SPM workbench support frame capable of automatically adjusting the horizontality, and belongs to the technical field of leveling workbenches of experimental instrument. The support frame comprises a metal frame, which is a rectangular structure. A set of pneumatic adjustment mechanisms is fixedly arranged on each corner of the metal frame; each set of pneumatic adjustment mechanisms comprises a pneumatic rod device, a height sensor and a linkage control system, and the pneumatic rod device comprises an upper column, a gas rod and a lower column from top to bottom, the upper column is connected to a corner of the metal frame, and the upper column and the lower column are connected through the gas rod; the height sensor is arranged on the edge of the metal frame near the column, and is used for measuring the distance between the height sensor and the ground in real time and outputting it to the linkage control system in the form of a digital signal; the linkage control system generates a controllable torque according to the digital signal to act on the gas rod, driving the upper column to rise or fall to a corresponding height, thereby realizing automatic adjustment of the horizontality of the support frame.

Description

Technical Field

[0001] The invention belongs to the technical field of leveling a workbench of an experimental instrument, and in particular relates to a SPM workbench support frame capable of automatically adjusting the horizontality. Background Art

[0002] Scanning Probe Microscope (SPM), including Scanning Tunneling Microscope (STM) and Atomic Force Microscope (AFM), is an instrument with atomic-level resolution. It can detect the physical and chemical properties of suitable samples at the nanoscale in the atmosphere, gas or liquid environment, or directly perform nanomanipulation. It is now widely used in the semiconductor, biological, chemical, food, and pharmaceutical industries, as well as various nano-related disciplines such as nano-functional materials.

[0003] SPM has high requirements for the measurement environment. External interference signals, such as vibration, levelness, electromagnetic waves, etc., will have a certain impact on its measurement results. Therefore, shielding or reducing external signal interference can greatly improve the quality of the final measurement results. For example, in terms of levelness, if the SPM is placed on a non-horizontal workbench, the distance between the final probe tip and the sample stage will gradually change, resulting in a serious deviation between the measurement image result and the actual situation; when the levelness deviation is large, the probe may scratch the sample, or even the tip may break.

[0004] In order to reduce the impact of levelness on the measurement behavior of SPM, many forms of levelness adjustment equipment have been introduced, such as pneumatic water platform, hydraulic water platform, etc. For pneumatic water platform, although the overall structure is relatively simple and the cost is low, its level can be adjusted in a small range, the pneumatic stability is poor, and it is greatly affected by external pressure; and an additional air pump is required, the air purification process is more complicated during use, and the impurities and water vapor in the air source must be purified; the air pump has a large noise when filling and exhausting, and the vibration will also cause strong interference to SPM when working. For hydraulic water platform, because the oil is used to bear the pressure, the liquid flow resistance is large and the efficiency is low; the oil cylinder needs to have good sealing, the hydraulic components require high manufacturing precision and are expensive; it is not easy to find the cause when the hydraulic components fail, and the use and maintenance require a high level of technology; and because the oil may leak, it cannot reach the cleanliness required for the normal operation of SPM. In addition, the patent "A table with automatic level adjustment" (202021402996.6) involves a table with automatic level adjustment, but the patent is realized through the linkage of a sealing ring, a hydraulic pump, and a hydraulic foot rod, and there are still problems such as high price, difficult maintenance, and failure to meet the cleanliness required by SPM. In addition, the table involved in the patent is mainly used by people of different heights and cannot meet the horizontal accuracy requirements of nano-scale scientific research instruments. The patent "A new table structure with desktop level" (201310379568.4) involves a new table structure with desktop level for ships. It mainly describes a new table structure that can maintain levelness when the ship shakes during driving, that is, the table use environment described in the patent is essentially different from the use environment of this patent. Summary of the invention

[0005] In order to solve the defects of the prior art, the purpose of the present invention is to provide a SPM workbench support frame that can automatically adjust the horizontality, and the use of the support frame can meet the SPM's adjustment requirements for horizontal accuracy.

[0006] In order to achieve the above purpose, a technical solution adopted by the present invention is:

[0007] An SPM workbench support frame capable of automatically adjusting the horizontality, comprising a metal frame and a plurality of pneumatic adjustment mechanisms, wherein the metal frame is a rectangular frame structure, and a set of the pneumatic adjustment mechanisms is fixedly arranged at each corner of the metal frame;

[0008] Each set of the pneumatic adjustment mechanism includes a pneumatic rod device, a height sensor and a linkage control system, wherein: the pneumatic rod device includes an upper column, a pneumatic rod and a lower column from top to bottom, the upper column is connected to a corner of the metal frame, and the upper column is connected to the lower column through the pneumatic rod;

[0009] The height sensor is fixedly arranged on the side of the metal frame near the upper column, and is used to measure the distance between the height sensor and the ground in real time and output it to the linkage control system in the form of a digital signal;

[0010] The linkage control system can generate a controllable torque of corresponding magnitude according to the digital signal, acting on the gas rod, and the gas rod drives the upper column to rise or fall to a corresponding height, thereby realizing automatic adjustment of the horizontality of the SPM workbench support frame.

[0011] Furthermore, as described above, the SPM workbench support frame capable of automatically adjusting the horizontality, the linkage control system includes a first signal converter, a first DC motor, a force signal mover, a force detector, a spring, an electromagnetic damper, a second signal converter and a second DC motor.

[0012] Furthermore, in the SPM workbench support frame that can automatically adjust the horizontality as described above, the first signal converter and the first DC motor are fixedly arranged on the edge of the metal frame near the upper column, and the first signal converter is communicatively connected to the height sensor to receive the digital signal input by the height sensor, and compare the real-time height with the set height value to generate a difference, and convert the difference into a first controllable current signal and output it to the first DC motor; the output shaft of the first DC motor is connected to the force signal mover, and the first DC motor converts the first controllable current signal into a controllable torque acting on the force signal mover, and then acts on the electromagnetic damping-spring through the force signal mover.

[0013] Furthermore, in the SPM workbench support frame that can automatically adjust the horizontality as described above, the electromagnetic damper and spring are fixedly arranged on the edge of the metal frame close to the upper column, and the spring is connected to the force signal mover; under the controllable torque output by the first DC motor, the electromagnetic damper and spring can move horizontally toward or away from the upper column at the same time, and during the movement, the electromagnetic damper-spring generates a restraining force that resists the movement.

[0014] Furthermore, as described above, in the SPM workbench support frame that can automatically adjust the horizontality, the force detector can be communicatively connected with the force signal mover and the spring, so as to detect the restraining force generated during the movement of the electromagnetic damping-spring, and output the restraining force in the form of a digital signal to the second signal converter.

[0015] Furthermore, in the SPM workbench support frame that can automatically adjust the horizontality as described above, the second signal converter and the second DC motor are fixedly arranged in the upper column, and the second signal converter is communicatively connected to the force detector for receiving the digital signal input by the force detector and converting it into a second controllable current signal and outputting it to the second DC motor; the second DC motor converts the second controllable current signal into a controllable torque acting on the gas rod, and the gas rod drives the upper column to rise or fall, thereby restoring to the original set height.

[0016] Furthermore, as described above, the SPM workbench support frame capable of automatically adjusting the levelness is also provided with a level gauge in the middle of each side of the metal frame, so as to facilitate intuitive observation of the levelness and adjustment process of the support frame.

[0017] Furthermore, in the SPM workbench support frame capable of automatically adjusting the horizontality as described above, a desktop panel is arranged on the upper surface of the metal frame, and ribs are arranged between the upper column and the metal frame to increase the structural strength of the support frame.

[0018] Furthermore, in the SPM workbench support frame capable of automatically adjusting the horizontality as described above, the lower end of the lower column is connected with a universal wheel.

[0019] Furthermore, as described above, in the SPM workbench support frame capable of automatically adjusting the horizontality, a limit ring is provided on the surface of the lower column to limit the minimum descending height of the upper column.

[0020] The SPM workbench support frame capable of automatically adjusting the levelness provided by the present invention has the following beneficial effects:

[0021] 1. Fast response speed. When the desktop is unbalanced due to external force, the response time of electromagnetic damping is much lower than other means due to the fast propagation speed of electromagnetic waves in the air. For example, the response time of hydraulic pressure is limited by the flow rate of the liquid and the blockage of the liquid caused by unreasonable structural design;

[0022] 2. The parameter settings are flexible and can be adjusted within a wide range. Since the damping force generated by electromagnetic damping is affected by the magnetic field, the magnetic field strength B can be changed to adjust the damping force, and the spring can also change its stiffness coefficient k to adjust the size of the damping force;

[0023] 3. Good stability, the damping stability can be improved by controlling its damping ratio;

[0024] 4. Strong temperature adaptability. For pneumatic and hydraulic media, gases and liquids are greatly affected by temperature, while the electromagnetic force of electromagnetic damping media is much less affected by temperature than gases and liquids. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 A front view of an SPM workbench support frame capable of automatically adjusting the levelness provided in a specific embodiment;

[0026] Figure 2 for Figure 1 A partial cross-sectional view of the support frame;

[0027] Figure 3 for Figure 1 A top view of the support frame;

[0028] Figure 4 for Figure 1 A working flow diagram of the support frame;

[0029] In the figure: 1-desktop panel; 2-rib plate; 3-upper column; 4-gas rod; 5-lower column; 6-universal wheel; 7-level; 8-charging port; 9-height sensor; 10-first signal converter; 11-first DC motor; 12-force signal mover; 13-force detector; 14-spring; 15-electromagnetic damping; 16-second signal converter; 17-second DC motor; 18-limiting ring; 19-power interface; 20-metal frame. DETAILED DESCRIPTION

[0030] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0031] See also Figure 1 to Figure 4 As shown, the SPM workbench support frame capable of automatically adjusting the horizontality provided by the present invention is mainly composed of a metal frame 20 and four sets of pneumatic adjustment mechanisms. The metal frame 20 is a rectangular frame structure, and a set of pneumatic adjustment mechanisms is fixedly arranged on each corner of the metal frame 20.

[0032] Each pneumatic adjustment mechanism is mainly composed of a pneumatic rod device, a height sensor 9 and a linkage control system, wherein:

[0033] Each set of pneumatic rod devices includes an upper column 3, a pneumatic rod 4 and a lower column 5 from top to bottom. The upper column 3 is connected to a corner of the metal frame 20. The upper column 3 and the lower column 5 are connected by the pneumatic rod 4. A limit ring 18 is provided on the column surface of the lower column 5. The lower end of the lower column 5 is connected to a universal wheel 6. The height of the lower column 5 is fixed; the upper column 3 can be driven by the pneumatic rod 4 to adjust the height, and can move to the height of the limit ring 18 at the lowest.

[0034] The height sensor 9 is fixedly arranged on the side of the metal frame 20 near the upper column 3, and is used to measure the distance between the height sensor 9 and the ground in real time and output it to the linkage control system in the form of a digital signal. Specifically, the height sensor 9 can be a laser rangefinder, which emits a laser to the ground, measures the distance between the height sensor 9 and the ground in real time and outputs it in the form of a digital signal.

[0035] The linkage control system includes a first signal converter 10, a first DC motor 11, a force signal mover 12, a force detector 13, a spring 14, an electromagnetic damper 15, a second signal converter 16 and a second DC motor 17, wherein:

[0036] The first signal converter 10 is fixedly arranged on the side of the metal frame 20 near the upper column 3, and is communicatively connected with the height sensor 9, and is used to receive the digital signal input by the height sensor 9, and compare the real-time height with the set height value to generate a difference, and the difference is converted into a first controllable current signal and output to the first DC motor 11. Specifically, the first signal converter 10 converts the digital signal into an electrical signal using a single-chip microcomputer and a current amplifier, and then converts the electrical signal into a controllable current signal using a unidirectional thyristor and outputs it to the first DC motor 11.

[0037] The first DC motor 11 is fixedly arranged on the side of the metal frame 20 near the upper column 3, and is communicatively connected to the first signal converter 10, and the output shaft of the first DC motor 11 is connected to the force signal mover 12. The first DC motor 11 receives the first controllable current signal input by the first signal converter 10, and converts the first controllable current signal into a controllable torque acting on the force signal mover 12, and then acts on the electromagnetic damper 15-spring 14 through the force signal mover 12.

[0038] The electromagnetic damper 15 and the spring 14 are fixedly arranged on the edge of the metal frame 20 near the upper column 3, and the spring 14 is connected to the force signal mover 12. Under the controllable torque output by the first DC motor 11, the electromagnetic damper 15 and the spring 14 can move horizontally toward or away from the upper column 3 at the same time, and during the movement, the electromagnetic damper 15-spring 14 generates a restraining force to resist the movement.

[0039] The force detector 13 is connected to the force signal mover 12 and the spring 14 , and is used to detect the restraining force generated during the movement of the electromagnetic damper 15 - the spring 14 , and output the restraining force to the second signal converter 16 in the form of a digital signal.

[0040] The second signal converter 16 is fixedly disposed in the upper column 3, and is communicatively connected with the force detector 13, and is used for receiving the digital signal input by the force detector 13, and converting the digital signal into a second controllable current signal and outputting it to the second DC motor 17. Specifically, the second signal converter 17 converts the digital signal into an electrical signal using a single-chip microcomputer and a current amplifier, and then converts the electrical signal into a controllable current signal using a one-way thyristor and outputs it to the second DC motor 17.

[0041] The second DC motor 17 is fixedly arranged in the upper column 3 and is communicatively connected to the second signal converter 16. It is used for receiving the second controllable current signal input by the second signal converter 16 and converting the second controllable current signal into a controllable torque acting on the gas rod 4. The gas rod 4 drives the upper column 3 to rise or fall, thereby restoring to the original set height.

[0042] A power interface 19 and a charging port 8 are provided at each corner of the metal frame 20 for providing power to the pneumatic adjustment mechanism.

[0043] A level meter 7 is also provided in the middle of each side of the metal frame 20 to facilitate visual observation of the horizontality and adjustment process of the support frame.

[0044] A desktop panel 1 is arranged on the upper surface of the metal frame 20, and a rib plate 2 is arranged between the upper column 3 and the metal frame 20 to increase the structural strength of the support frame.

[0045] The working principle of the above-mentioned workbench support frame capable of automatically adjusting the horizontality is as follows:

[0046] When the upper column 3 is subjected to force, assuming it descends from the set height, the height sensor 9 detects the real-time height; the digital signal of the real-time height is transmitted to the first signal converter 10, the first signal converter 10 compares the real-time height with the set height value to generate a difference, and the difference is converted into a first current signal output; the first current signal is input to the first DC motor 11 and converted into a controllable torque, and acts on the electromagnetic damping 15-spring 14 through the force signal mover 12; the torque causes the electromagnetic damping 15-spring 14 to move toward the column direction at the same time, and an inhibitory force resisting movement is generated inside the electromagnetic damping 15-spring 14, which is detected by the force sensor 13 and output to the second signal converter 16, and the second signal converter outputs a second current signal and controls the second DC motor to generate a controllable torque, which acts on the gas rod 4, so that the upper column 3 rises and returns to the original set height.

[0047] The following is a specific calculation example to illustrate the adjustment process of the above-mentioned workbench support frame that can automatically adjust the horizontality.

[0048] Assume that the original height of a column of the support frame is set to a meter, and a force of x Newton is applied to the column, causing the column to drop in height. The height sensor at the same height of the column measures the real-time height b meters between the column and the ground in real time, and outputs it to the first signal converter in the form of a digital signal. In the first signal converter, the real-time height b meters is detected and compared with the original height value a meter, and the height difference (ab) meters is calculated. At this time, the height difference (ab) is a function of x.

[0049] The first signal converter converts the height difference signal into a first current signal and outputs it to the first DC motor, and the first DC motor generates a controllable torque y Newton (N) and acts on the electromagnetic damping-spring. At this time, the size of y is related to the height difference (ab), that is, x can be converted into y.

[0050] Under the action of the controllable force y, the electromagnetic damper-spring simultaneously moves toward the column direction and generates a restraining force k Newton (N) inside to resist the movement, where k is related to the electromagnetic damper-spring constant coefficients A and B and the controllable force y. The force sensor detects the magnitude of the restraining force k and inputs it into the second signal converter.

[0051] The second signal converter converts the mechanical digital signal into a second current signal and inputs it into the second DC motor. The DC motor outputs a controllable force z Newton (N) to act on the gas rod, so that the upper column rises b meters and returns to the original set height. At this time, z is related to the restraining force k, the weight of the upper column, etc.

[0052] The present invention provides an SPM workbench support frame that can automatically adjust the horizontality, which has the advantages of real-time, smooth and stable adjustment of the horizontality, that is, automatic adjustment when non-horizontal is detected, smooth movement during adjustment, and stable maintenance after adjustment; the electromagnetic damping involved in the invention has the characteristics of low power consumption, fast response, good fault tolerance and low cost, so that the support frame has the advantages of real-time response, smooth adjustment process, strong temperature adaptability, low energy consumption, wide adjustment range, etc. during use, and can better adapt to the SPM requirements for horizontal accuracy.

[0053] The above-described embodiments are merely illustrative of the present invention, rather than all embodiments. The present invention may also be implemented in other specific ways or other specific forms without departing from the gist or essential features of the present invention. Therefore, the described embodiments should be considered illustrative rather than restrictive in any respect. The scope of the present invention should be described by the attached claims, and any changes equivalent to the intent and scope of the claims should also be included within the scope of the present invention.

Claims

1. A SPM workbench support frame capable of automatically adjusting the levelness, characterized in that: It includes a metal frame and multiple sets of pneumatic adjustment mechanisms, wherein the metal frame is a rectangular frame structure, and each corner of the metal frame is fixedly provided with a set of the pneumatic adjustment mechanisms; Each set of the pneumatic adjustment mechanism includes a pneumatic rod device, a height sensor and a linkage control system, wherein: the pneumatic rod device includes an upper column, a pneumatic rod and a lower column from top to bottom, the upper column is connected to a corner of the metal frame, and the upper column is connected to the lower column through the pneumatic rod; The height sensor is fixedly arranged on the side of the metal frame near the upper column, and is used to measure the distance between the height sensor and the ground in real time and output it to the linkage control system in the form of a digital signal; The linkage control system can generate a controllable torque of corresponding magnitude according to the digital signal, acting on the gas rod, and the gas rod drives the upper column to rise or fall to a corresponding height, thereby realizing automatic adjustment of the horizontality of the SPM workbench support frame; the linkage control system includes a first signal converter, a first DC motor, a force signal mover, a force detector, a spring, an electromagnetic damper, a second signal converter and a second DC motor; the first signal converter and the first DC motor are fixedly arranged on the edge of the metal frame near the upper column, and the first signal converter is communicatively connected to the height sensor for receiving the height sensor The input digital signal is compared with the real-time height and the set height value to generate a difference, and the difference is converted into a first controllable current signal and output to the first DC motor; the output shaft of the first DC motor is connected to the force signal mover, and the first DC motor converts the first controllable current signal into a controllable torque to act on the force signal mover, and then acts on the electromagnetic damping-spring through the force signal mover; the force detector is communicatively connected with the force signal mover and the spring, and is used to detect the restraining force generated during the movement of the electromagnetic damping-spring, and output the restraining force in the form of a digital signal to the second signal converter.

2. The SPM workbench support frame capable of automatically adjusting the levelness as claimed in claim 1, characterized in that: The electromagnetic damper and spring are fixedly arranged on the edge of the metal frame near the upper column, and the spring is connected to the force signal mover; under the controllable torque output by the first DC motor, the electromagnetic damper and spring can move horizontally toward or away from the upper column at the same time, and during the movement, the electromagnetic damper-spring generates a restraining force that resists movement.

3. The SPM workbench support frame capable of automatically adjusting the levelness as claimed in claim 2, characterized in that: The second signal converter and the second DC motor are fixedly arranged in the upper column. The second signal converter is communicatively connected to the force detector, and is used to receive the digital signal input by the force detector and convert it into a second controllable current signal and output it to the second DC motor; the second DC motor converts the second controllable current signal into a controllable torque acting on the gas rod, and the gas rod drives the upper column to rise or fall, thereby restoring to the original set height.

4. The SPM workbench support frame capable of automatically adjusting the levelness according to any one of claims 1 to 3, characterized in that: A level is also provided in the middle of each side of the metal frame to facilitate visual observation of the horizontality and adjustment process of the support frame.

5. The SPM workbench support frame capable of automatically adjusting the levelness as claimed in claim 1, characterized in that: A desktop panel is arranged on the upper surface of the metal frame, and a rib is arranged between the upper column and the metal frame to increase the structural strength of the support frame.

6. The SPM workbench support frame capable of automatically adjusting the levelness according to claim 1, characterized in that: The lower end of the lower column is connected with a universal wheel.

7. The SPM workbench support frame capable of automatically adjusting the levelness according to claim 5 or 6, characterized in that: A limiting ring is arranged on the surface of the lower column to limit the lowest descending height of the upper column.

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