Absolute method sinusoidal force sensor dynamic calibration device

Abstract

The utility model provides a kind of absolute method sine force sensor dynamic calibration device, including rack, vibration table, rack is provided with mirror frame, several side laser vibration meters, a top laser vibration meter, vibration table is provided with force sensor, mass block is provided on force sensor, vibration table is separated from rack, mirror frame is provided with mirror corresponding to side laser vibration meter one to one, the upper end surface of mass block is provided with center measuring point and several non-center measuring point;Laser round trip light path is formed between side laser vibration meter and non-center measuring point on mass block by mirror;Laser round trip light path is formed between top laser vibration meter and center measuring point on mass block.The utility model changes the path of laser by the reflection of multiple mirrors, so that the laser beams emitted by each side laser vibration meter can be accurately hit on measuring point on the upper end surface of mass block, thereby meeting the test calibration requirement of force sensor.

Description

Technical Field

[0001] This utility model relates to the field of sensor calibration technology, and in particular to a dynamic calibration device for an absolute sinusoidal force sensor. Background Technology

[0002] The absolute sinusoidal force calibration device is used for the dynamic characteristic calibration of force sensors. The calibration system mainly consists of a standard vibration table, sensor, mass block, and laser vibrometer (see attached diagram). Figure 4 (As shown). A standard vibration table provides a sinusoidal force at a specific frequency. The lower end of the force sensor is mounted on the vibration table via a lower connector, and the upper end of the upper force sensor is connected to the mass block via an upper connector, thus linking with the standard vibration table. The lens of the laser vibrometer emits a laser beam, which acts on the center point of the upper surface of the mass block to measure the acceleration value of the center point of the upper end of the mass block during the entire system motion. Then, the dynamic force value borne by the force sensor at a specific frequency is calculated through a corresponding compensation algorithm.

[0003] To improve the accuracy of the test, multiple different measurement points are usually selected on the upper surface of the mass block. Multiple laser vibrometers are used to simultaneously measure the acceleration values ​​at different measurement points to obtain the acceleration distribution at multiple different locations on the upper surface of the mass block.

[0004] Given that current laser vibrometers on the market are relatively large, while the mass block in a standard device for a small range (e.g., a force measurement range of 10N-250N) is relatively small (with a small upper surface area), if two or more laser vibrometers are placed side by side vertically upside down, the large distance between their lenses will prevent the projected laser beams from falling completely on the upper surface of the mass block. Summary of the Invention

[0005] The purpose of this invention is to address the shortcomings of existing technologies and provide a dynamic calibration device for an absolute sinusoidal force sensor.

[0006] The purpose of this utility model is achieved through the following technical solution: a dynamic calibration device for an absolute sinusoidal force sensor, comprising a frame and a vibration table. The frame is equipped with a reflector frame, several lateral laser vibrometers, and a top laser vibrometer. A force sensor is mounted on the vibration table, and a mass block is mounted on the force sensor. The vibration table is separated from the frame. The reflector frame is equipped with reflectors corresponding to the lateral laser vibrometers. The upper surface of the mass block has a central measurement point and several non-central measurement points. The reflectors create a laser back-and-forth optical path between the lateral laser vibrometers and the non-central measurement points on the mass block; a laser back-and-forth optical path is also created between the top laser vibrometer and the central measurement point on the mass block.

[0007] Preferably, the frame is provided with an installation platform, and the reflector frame is installed on the installation platform; a level is provided on the installation platform for detecting the levelness of the installation platform.

[0008] Preferably, a quadrangular pyramid is provided on the reflector frame, and the reflector is provided on the four sides of the quadrangular pyramid; a through hole is provided in the center of the quadrangular pyramid, and the through hole is located directly above the center of the mass block; the through hole is used to allow the laser beam of the top laser vibrometer to pass through.

[0009] Preferably, the frame is provided with a height adjustment seat, which is adjustablely mounted on the upright of the frame. The height adjustment seat is provided with a horizontal angle adjustment mechanism, which includes a rotating base mounted on the height adjustment seat. The rotating base is rotatably mounted on the height adjustment seat, and a side laser vibration meter is mounted on the rotating base. A protrusion is provided on the side of the rotating base. An adjustment seat is provided on the height adjustment seat, and a threaded pusher and an elastic push rod are provided on the adjustment seat. The threaded pusher and the elastic push rod respectively press against the two sides of the protrusion.

[0010] Preferably, the rotating base is cylindrical, and a positioning element and an elastic pressing column are provided on the height adjustment seat. The positioning element and the elastic pressing column are located on both sides of the rotating base. The positioning element is provided with an arc positioning surface that matches the side of the rotating base, and the side of the rotating base contacts the arc positioning surface. The elastic pressing column applies elastic pressure to the side of the rotating base, and the direction of the elastic pressure is towards the positioning element.

[0011] Preferably, the frame is provided with a counterweight for adjusting the frame's natural frequency, and the bottom of the frame is provided with a shock-absorbing device.

[0012] Preferably, the top of the frame is provided with a guide rail, and a top movable part is adjustablely provided on the guide rail, with the top laser vibration meter mounted on the top movable part.

[0013] The beneficial effects of this utility model are as follows: Based on the fact that the laser vibrometers currently on the market are relatively large in size, if two or more laser vibrometers are placed side by side, the large distance between their lenses will cause the projected laser beams to not fall completely on the upper surface of the mass block. This utility model changes the path of the laser by using the reflection effect of multiple mirrors, so that the laser beams emitted by each side laser vibrometer can accurately hit the measurement points on the upper surface of the mass block, thereby meeting the testing and calibration requirements of the force sensor. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the utility model.

[0015] Figure 2 This is a schematic diagram of the reflector frame.

[0016] Figure 3 This is a partial structural diagram of the laser vibration meter located on the side of the test bench.

[0017] Figure 4 This is a schematic diagram of a calibration system in the prior art, consisting of a standard vibration table, a sensor, a mass block, and a laser vibration meter.

[0018] In the diagram: 1. Frame, 2. Mounting platform, 3. Reflector frame, 4. Vibration table, 5. Force sensor, 6. Mass block, 7. Side laser vibration meter, 8. Top laser vibration meter, 9. Counterweight, 10. Level, 11. Top movable part, 12. Vibration damping device, 13. Four-sided pyramid, 14. Reflector, 15. Through hole, 16. Height adjustment seat, 17. Rotating base, 18. Positioning component, 19. Elastic jacking column, 20. Adjustment seat, 21. Threaded pusher, 22. Elastic push rod, 23. Protrusion. Detailed Implementation

[0019] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present utility model are within the protection scope of the present utility model.

[0020] like Figures 1 to 3 As shown, a dynamic calibration device for an absolute sinusoidal force sensor includes a frame 1 and a vibration table 4. The frame 1 is equipped with a reflector frame 3, several lateral laser vibrometers 7, and a top laser vibrometer 8. The vibration table 4 is equipped with a force sensor 5, and a mass block 6 is mounted on the force sensor 5. The vibration table 4 is separated from the frame 1. The reflector frame 3 is equipped with reflectors 14 corresponding to the lateral laser vibrometers 7. The upper surface of the mass block 6 has a central measurement point and several non-central measurement points. A laser round-trip optical path is formed between the lateral laser vibrometers 7 and the non-central measurement points on the mass block 6 through the reflectors 14; a laser round-trip optical path is also formed between the top laser vibrometer 8 and the central measurement point on the mass block 6.

[0021] The frame 1 is constructed of alloy profiles and includes four columns. The mass block 6 is positioned directly below the reflector frame 3. The reflector 14 on the reflector frame 3 is placed at a 45-degree angle. A laser beam emitted from the side laser vibrometer 7 is reflected by the reflector 14 and then shines on the measurement point on the upper surface of the mass block 6. The laser beam, after being reflected by the mass block 6, returns to the side laser vibrometer 7 along the same path. Meanwhile, a laser beam emitted from the top laser vibrometer 8 directly illuminates the center of the upper surface of the mass block 6 from the top, and after being reflected by the mass block 6, returns to the top laser vibrometer 8 along the same path.

[0022] Given the large size of current laser vibrometers on the market, if two or more laser vibrometers are placed side by side, the large distance between their lenses will cause the projected laser beams to not fall completely on the upper surface of the mass block 6. This invention uses the reflection effect of multiple reflectors 14 to change the path of the laser, so that the laser beams emitted by each side laser vibrometer 7 can accurately hit the measurement points on the upper surface of the mass block 6, thereby meeting the testing and calibration requirements of the force sensor 5.

[0023] The frame 1 is equipped with a mounting platform 2, and the reflector frame 3 is mounted on the mounting platform 2. A level 10 is installed on the mounting platform 2 to detect the levelness of the mounting platform 2. The level 10 is used to detect the levelness of the mounting platform 2 to ensure that the mounting platform 2 is arranged horizontally and to reduce the impact of the mounting platform 2 tilting on the test.

[0024] like Figure 2 As shown, a quadrangular pyramid 13 is provided on the reflector frame 3, and a reflector 14 is provided on the four sides of the quadrangular pyramid 13; a through hole 15 is provided in the center of the quadrangular pyramid 13, and the through hole 15 is located directly above the center of the mass block 6; the through hole 15 is used to allow the laser beam of the top laser vibration meter 8 to pass through.

[0025] like Figure 3 As shown, a height adjustment seat 16 is provided on the frame 1. The height adjustment seat 16 is adjustablely mounted on the column of the frame 1. A horizontal angle adjustment mechanism is provided on the height adjustment seat 16. The horizontal angle adjustment mechanism includes a rotating base 17 mounted on the height adjustment seat 16. The rotating base 17 is rotatably mounted on the height adjustment seat 16. A side laser vibration meter 7 is mounted on the rotating base 17. A protrusion 23 is provided on the side of the rotating base 17. An adjustment seat 20 is provided on the height adjustment seat 16. A threaded pusher 21 and an elastic push rod 22 are provided on the adjustment seat 20. The threaded pusher 21 and the elastic push rod 22 respectively press against the two sides of the protrusion 23.

[0026] The height adjustment seat 16 is used to adjust the height of the side laser vibration meter 7, and the rotating base 17 is used to adjust the horizontal direction of the side laser vibration meter 7. By precisely adjusting the height and horizontal direction of the side laser vibration meter 7, the laser emitted by the side laser vibration meter 7 can accurately fall on the measurement point on the mass block 6. When the rotating base 17 is stationary, the elastic push rod 22 applies elastic pressure to the protrusion 23 in the direction of the threaded pusher 21, thereby pressing the protrusion 23 between the elastic push rod 22 and the threaded pusher 21. When it is necessary to adjust the horizontal direction of the side laser vibration meter 7, the protrusion 23 is moved by rotating the threaded pusher 21. When the protrusion 23 moves, it drives the rotating base 17 to rotate, thereby adjusting the horizontal direction of the side laser vibration meter 7.

[0027] The rotating base 17 is cylindrical. A positioning element 18 and an elastic pressing column 19 are mounted on the height adjustment seat 16. The positioning element 18 and the elastic pressing column 19 are located on opposite sides of the rotating base 17. The positioning element 18 has an arc-shaped positioning surface that matches the side surface of the rotating base 17, and the side surface of the rotating base 17 contacts the arc-shaped positioning surface. The elastic pressing column 19 applies elastic pressure to the side surface of the rotating base 17, with the direction of this elastic pressure towards the positioning element 18. Under this elastic pressure, the rotating base 17 can stably rest against the arc-shaped positioning surface of the positioning element 18.

[0028] A counterweight 9 is installed on the frame 1 to adjust its natural frequency, and a vibration damping device 12 is installed at the bottom of the frame 1. Although the vibration table 4 is separate from the frame 1, its vibration may be transmitted to the frame 1 through the ground or base during operation, which may adversely affect the accuracy of the measurement. In this invention, by adding a counterweight 9 to the frame 1, the counterweight 9 can increase the overall weight and natural frequency of the frame 1, improve the stability of the frame 1, and reduce the vibration impact of the vibration table 4 on the frame 1. The vibration damping device 12 installed at the bottom of the frame 1 can effectively isolate the frame 1 from vibration, further reducing the influence of external vibrations on the frame 1 and ensuring the reliability of the test results.

[0029] The top of the frame 1 is equipped with a guide rail, on which a top movable part 11 is adjustable. The top laser vibration meter 8 is mounted on the top movable part 11. The top movable part 11 can slide along the guide rail to adjust the position of the top laser vibration meter 8, ensuring that the top laser vibration meter 8 can be accurately aligned with the measurement point.

[0030] This invention relates to a laser vibration meter that utilizes the laser Doppler principle. When a laser beam illuminates the surface of a moving object, the frequency of the reflected light changes due to the object's motion, and this frequency change is proportional to the object's velocity. By measuring the frequency difference between the reflected and incident light, the vibration velocity of the object can be calculated, and thus parameters such as the vibration amplitude and acceleration can be obtained.

[0031] This utility model is not limited to the above-described preferred embodiments. Anyone can derive other forms of products under the guidance of this utility model. However, regardless of any changes made in their shape or structure, any technical solution that is the same as or similar to this application falls within the protection scope of this utility model.

Claims

1. A dynamic calibration device for an absolute sinusoidal force sensor, characterized in that, The system includes a frame and a vibration table. The frame is equipped with a reflector frame, several lateral laser vibrometers, and a top laser vibrometer. A force sensor is mounted on the vibration table, and a mass block is mounted on the force sensor. The vibration table is separate from the frame. The reflector frame is equipped with reflectors corresponding to the lateral laser vibrometers. The upper surface of the mass block has a central measurement point and several non-central measurement points. The reflectors form a laser round-trip optical path between the lateral laser vibrometers and the non-central measurement points on the mass block, and a laser round-trip optical path between the top laser vibrometer and the central measurement point on the mass block.

2. The dynamic calibration device for an absolute sinusoidal force sensor according to claim 1, characterized in that, The frame is equipped with an installation platform, and the reflector frame is installed on the installation platform; a level is installed on the installation platform to detect the levelness of the installation platform.

3. The dynamic calibration device for an absolute sinusoidal force sensor according to claim 1, characterized in that, A quadrangular pyramid is provided on the reflector frame, and the reflector is provided on the four sides of the quadrangular pyramid; a through hole is provided in the center of the quadrangular pyramid, and the through hole is located directly above the center of the mass block; the through hole is used to allow the laser beam of the top laser vibration meter to pass through.

4. The dynamic calibration device for an absolute sinusoidal force sensor according to claim 1, characterized in that, The frame is equipped with a height adjustment seat, which is adjustablely mounted on the frame's uprights. The height adjustment seat is equipped with a horizontal angle adjustment mechanism, which includes a rotating base mounted on the height adjustment seat. The rotating base is rotatably mounted on the height adjustment seat, and a side laser vibration meter is mounted on the rotating base. The side of the rotating base is provided with a protrusion. The height adjustment seat is equipped with an adjustment seat, which is equipped with a threaded pusher and an elastic push rod. The threaded pusher and the elastic push rod respectively abut against both sides of the protrusion.

5. The dynamic calibration device for an absolute sinusoidal force sensor according to claim 4, characterized in that, The rotating base is cylindrical, and a positioning element and an elastic pressing column are provided on the height adjustment seat. The positioning element and the elastic pressing column are located on the two sides of the rotating base respectively. The positioning element is provided with an arc positioning surface that matches the side of the rotating base, and the side of the rotating base contacts the arc positioning surface. The elastic pressing column applies elastic pressure to the side of the rotating base, and the direction of the elastic pressure is towards the positioning element.

6. The dynamic calibration device for an absolute sinusoidal force sensor according to claim 1, characterized in that, The frame is equipped with a counterweight for adjusting the frame's natural frequency, and the bottom of the frame is equipped with a shock-absorbing device.

7. The dynamic calibration device for an absolute sinusoidal force sensor according to claim 1, characterized in that, The top of the frame is equipped with a guide rail, and a top movable component is adjustablely mounted on the guide rail. The top laser vibration meter is mounted on the top movable component.

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