A calibration device for an eddy current sensor driven by a vibrator

Abstract

This utility model relates to the field of sensor calibration technology, and in particular to a calibration device for an eddy current sensor driven by a vibrator. The device includes a calibration apparatus fixedly mounted on the vibrator and a measuring target mounted on the vibrator's moving rod. The calibration apparatus includes a base plate fixed on the vibrator, a lifting platform mounted on the base plate, a sensor mounting plate mounted on the lifting platform, a dial indicator mounting bracket mounted on the base plate, and a dial indicator body mounted on the dial indicator mounting bracket. Through the structural design of the sensor mounting plate's adapter window and a third tightening knob, eddy current sensors with various nominal probe diameters (5 mm, 8 mm, and 16 mm) and corresponding mounting thread specifications can be stably fixed. Combined with the longitudinal height adjustment of the lifting platform and the lateral position adjustment of the sensor mounting plate, along with real-time monitoring of the sensor mounting plate's position by the dial indicator, it ensures that sensors of different specifications are accurately aligned with the measuring target.

Description

Technical Field

[0001] This utility model relates to the field of sensor calibration technology, and in particular to a calibration device for an eddy current sensor driven by an exciter. Background Technology

[0002] In the industrial sector, rotating equipment such as steam turbines and generator sets are core production equipment, and their operating status directly affects production safety and costs. When a rotating shaft rotates, it is prone to additional vibrations due to factors such as bearing wear, load imbalance, unstable medium flow, and deteriorated lubrication. Vibrations that are not monitored and controlled in a timely manner can easily lead to equipment damage, unit shutdowns, and economic losses and safety accidents. Therefore, predicting defects and guiding operation and maintenance by monitoring parameters such as shaft vibration has become crucial to ensuring the safe operation of equipment, leading to the continuous emergence of various vibration measurement sensors and methods. Eddy current displacement sensors, due to their advantages of non-contact operation, good linearity, and high resolution, are widely used in the vibration and displacement measurement of rotating equipment. They can realize the measurement of dynamic vibration and static clearance changes and have become an essential configuration for large units in industries such as power and petrochemicals, and are also used in position measurement and control in the field of automation.

[0003] The accuracy of sensor measurements determines the reliability of monitoring, making calibration crucial. Traditional static calibration, which involves measuring the distance between the sensor and the target and fitting the sensitivity based on the output voltage, is complex, time-consuming, and only yields static simulated values, failing to reflect the actual vibration measurement conditions of the sensor. Furthermore, it requires calibration at a professional facility, resulting in high costs and long cycles.

[0004] Existing calibration schemes that use swashplate rotation to simulate vibration still have shortcomings: they can only simulate single gap changes and cannot reproduce complex working conditions; the swashplate must be the same material as the rotating shaft, and the customization cycle is long and the cost is high when the material is changed.

[0005] In summary, existing calibration schemes suffer from problems such as a disconnect between accuracy and operating conditions, poor adaptability, high cost, and long cycle times, which affect the reliability of sensor applications. Therefore, developing calibration technologies that overcome these shortcomings is of great significance for ensuring the safe operation of rotating equipment and is a key research focus in this field. Utility Model Content

[0006] To overcome the shortcomings mentioned above, this utility model aims to provide a technical solution that can solve the above problems.

[0007] A calibration device for an eddy current sensor driven by a vibrator includes a calibration device fixedly mounted on the vibrator and a measurement target mounted on the moving rod of the vibrator. The calibration device includes a base plate fixed on the vibrator, a lifting platform mounted on the base plate, a sensor mounting plate mounted on the lifting platform, a dial indicator mounting bracket mounted on the base plate, and a dial indicator body mounted on the dial indicator mounting bracket. The dial indicator body acts on the sensor mounting plate, which has a sensor mounting structure for fixing the eddy current sensor so that the eddy current sensor is aligned with the measurement target.

[0008] Preferably, feet are provided at the corners of the base plate, and base plate fixing screws are provided at the corresponding positions of the feet on the base plate.

[0009] Preferably, the base plate is a right-angled triangular plate structure, and a clearance opening is provided at the middle position of the hypotenuse of the base plate, with the measuring target corresponding to the position of the clearance opening.

[0010] Preferably, the lifting platform includes a first T-shaped block fixedly installed on the base plate and a second T-shaped block slidably connected to the first T-shaped block in the longitudinal direction. A first tightening knob is connected between the first T-shaped block and the second T-shaped block, and the first T-shaped block and the second T-shaped block are tightened and fixed by the first tightening knob.

[0011] Preferably, both the first T-block and the second T-block have vertical mating surfaces. The mating surfaces of the first T-block and the second T-block are respectively provided with a first sliding groove and a first sliding rail, so that the first T-block and the second T-block can slide together through the first sliding groove and the first sliding rail. The first tightening knob fixes the first T-block and the second T-block by passing through the first sliding groove and abutting against the first sliding rail.

[0012] Preferably, the upper end of the second T-block and the lower end of the sensor fixing plate are respectively provided with a second sliding groove and a second sliding rail. The sensor fixing plate is slidably connected to the second T-block through the sliding cooperation of the second sliding groove and the second sliding rail. A second tightening knob is also connected to the sensor fixing plate. The second tightening knob is used to abut against the second T-block. After the sensor fixing plate is adjusted to a suitable position on the second T-block, the sensor fixing plate and the second T-block are fixed by tightening the second tightening knob.

[0013] Preferably, the sensor fixing structure includes an adapter window formed on the sensor fixing plate and a third tightening knob threaded to one side of the sensor fixing plate. One end of the third tightening knob extends into the adapter window to longitudinally press the eddy current sensor against the adapter window.

[0014] Preferably, the adapter window has two symmetrical surfaces that fit together at an angle on the side away from the third tightening knob, and the eddy current sensor is centered by abutting against the two symmetrical surfaces.

[0015] Preferably, the dial indicator mounting bracket includes a column vertically mounted on a base plate and a crossbar vertically connected to the column. One end of the crossbar extends directly above the sensor mounting plate. The dial indicator body is fixedly mounted at the extended end of the crossbar. The dial indicator body has a side rod assembly that is connected to the sensor mounting plate.

[0016] Preferably, both ends of the crossbar are provided with connecting through holes, and the inner side of the connecting through holes is provided with a pressure slit that passes through the end of the crossbar. A fourth tightening knob is threadedly connected to the crossbar at the position corresponding to the toothed slot. The crossbar is connected to the column and the dial indicator body through the two connecting through holes respectively, and is fixedly engaged with the column and the dial indicator body respectively by tightening the fourth tightening knob.

[0017] Compared with the prior art, the beneficial effects of this utility model are: The sensor mounting plate's adapter window, combined with a third tightening knob, allows for stable mounting of eddy current sensors with various nominal probe diameters (5mm, 8mm, and 16mm) and corresponding mounting thread specifications. Combined with the vertical height adjustment of the lifting platform and the lateral position adjustment of the sensor mounting plate, along with real-time monitoring of the sensor mounting plate's position using a dial indicator, it ensures precise alignment of sensors of different specifications with the measurement target. Furthermore, the measurement target can be manually and quickly installed and removed via a threaded structure. When the actual measurement shaft material changes, only a measurement target of the same material needs to be replaced, eliminating the need for manufacturer customization and significantly shortening the replacement cycle. The entire calibration device has a simple structure; each component is assembled and fixed using screws, sliding rails, and tightening knobs. The dynamic calibration operation process is clear, requiring only simple steps such as target fixing, base plate assembly, sensor fixing, position adjustment, and wiring connection, making assembly and operation easy. In addition, the device's compact structure and portable integrated vibrator enable on-site calibration, eliminating the need to send sensors to professional locations, further shortening the calibration cycle, reducing time and transportation costs, and improving calibration reliability and stability.

[0018] Additional aspects and advantages of this invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a schematic diagram of the structure of this utility model installed on the vibrator; Figure 2 This is a three-view structural schematic diagram of this utility model; Figure 3 This is a structural schematic diagram of the present invention from one perspective; Figure 4 This is a structural schematic diagram from another perspective of the present invention; Figure 5 This is a structural schematic diagram from another perspective of this utility model.

[0021] The reference numerals and names in the figure are as follows: Vibrator 10, measuring target 20, base plate 30, base foot 31, base plate fixing screw 32, clearance opening 33, lifting platform 40, first T-block 41, second T-block 42, first tightening knob 43, first slide groove 44, first slide rail 45, sensor fixing plate 50, second slide groove 51, second slide rail 52, second tightening knob 53, dial indicator fixing bracket 60, column 61, crossbar 62, connecting through hole 63, pressure seam 64, fourth tightening knob 65, dial indicator body 70, sensor fixing structure 80, adapter window 81, third tightening knob 82, symmetry plane 83, eddy current sensor 90. Detailed Implementation

[0022] The technical solutions in the embodiments of this utility model will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0023] Please see Figure 1-5 In this embodiment of the present invention, an eddy current sensor calibration device driven by a vibrator is provided to achieve dynamic and accurate calibration of the eddy current sensor 90. The core of the device uses a lightweight, wide-frequency electromagnetic vibrator 10 as the vibration driving component. The electromagnetic vibrator 10 is a portable integrated vibrator 10 that integrates the four functions of the vibrator 10 body with a moving rod, a power amplifier, a vibration signal source, and a vibration controller, which can meet the requirements of vibration controllability and portability for the calibration of the eddy current sensor 90. The calibration device mainly includes a calibration mechanism fixedly installed on the vibrator 10 and a measurement target 20 installed on the moving rod of the vibrator 10. The calibration mechanism consists of a base plate 30, a lifting platform 40, a sensor fixing plate 50, a dial indicator fixing bracket 60, and a dial indicator body 70.

[0024] The base plate 30 adopts a right-angled triangular plate structure, and mounting holes are opened at all corners. Mounting feet 31 are adapted in the mounting holes, and base plate fixing screws 32 are installed on the base plate 30 at the corresponding positions of the feet 31. By aligning the mounting holes of the base plate 30 with the two mounting holes on the vibrator 10 body and tightening the base plate fixing screws 32, a stable connection between the base plate 30 and the vibrator 10 can be achieved. At the same time, a clearance opening 33 is opened at the middle position of the corresponding hypotenuse of the base plate 30. The measuring target 20 is installed at the clearance opening 33 to ensure that the measuring target 20 is accurately connected to the eddy current sensor 90 installed later. The lifting platform 40 is fixedly installed on the base plate 30. It includes a first T-shaped block 41 and a second T-shaped block 42. The first T-shaped block 41 is fixed on the base plate 30, and the second T-shaped block 42 is slidably connected to the first T-shaped block 41 along the longitudinal direction. Both the first T-shaped block 41 and the second T-shaped block 42 have vertical mating surfaces. A first sliding groove 44 and a first sliding rail 45 are respectively provided on the mating surfaces. The two slide and guide each other through the cooperation of the first sliding groove 44 and the first sliding rail 45. A first tightening knob 43 is connected between the first T-shaped block 41 and the second T-shaped block 42. The first tightening knob 43 passes through the first sliding groove 44 and abuts against the first sliding rail 45. Tightening the first tightening knob 43 will allow the lifting platform to slide smoothly. The first T-block 41 and the second T-block 42 are relatively fixed, thereby realizing the height adjustment of the lifting platform 40. The sensor fixing plate 50 is installed on the second T-block 42 of the lifting platform 40. The upper end of the second T-block 42 is provided with a second slide rail 52, and the lower end of the sensor fixing plate 50 is provided with a corresponding second slide groove 51. The two are laterally slidably connected through the sliding cooperation of the second slide rail 52 and the second slide groove 51. The sensor fixing plate 50 is also threadedly connected with a second tightening knob 53. One end of the second tightening knob 53 abuts against the second T-block 42. By tightening the second tightening knob 53, the sensor fixing plate 50 can be fixed in a suitable position on the second T-block 42. The sensor mounting plate 50 is provided with a sensor mounting structure 80, which includes an adapter window 81 opened on the sensor mounting plate 50 and a third tightening knob 82 threaded to one side of the sensor mounting plate 50. One end of the third tightening knob 82 extends into the adapter window 81 to press the longitudinal eddy current sensor 90 against the adapter window 81. The adapter window 81 can accommodate eddy current sensors 90 of different specifications, including sensors with nominal probe diameters of 5 mm, 8 mm and 16 mm and corresponding mounting thread specifications. The dial indicator mounting bracket 60 is fixedly installed on the base plate 30, the dial indicator body 70 is installed on the dial indicator mounting bracket 60, and the probe of the dial indicator body 70 acts on the sensor mounting plate 50 to accurately monitor the position change of the sensor mounting plate 50, and assist in achieving accurate alignment between the eddy current sensor 90 and the measurement target 20. The measuring target 20 is made of the same metal material as the actual measuring shaft. It has a threaded structure on one side, which can be manually tightened and fixed to the moving rod of the vibrator 10. The other side is a flat measuring plane, which is used to simulate the surface of the actual target being measured.

[0025] The dynamic calibration operation process of this embodiment is as follows: First, the 4140 steel measuring target 20 is manually tightened and fixed to the corresponding position of the moving rod of the vibrator 10 through its threaded end; then, the mounting holes of the base plate 30 are aligned with the two mounting holes on the body of the vibrator 10, and after the base feet 31 are installed in the mounting holes of the base plate 30, the base plate fixing screws 32 at the corresponding positions on the base plate 30 are tightened to complete the stable assembly of the base plate 30 and the vibrator 10; next, the eddy current sensor 90 to be calibrated is placed in the adapter window 81 of the sensor fixing plate 50, and the third tightening knob 82 is tightened so that the end of the third tightening knob 82 extends into the adapter window 81 to longitudinally press and fix the eddy current sensor 90; according to the size specifications of the eddy current sensor 90 to be calibrated, the relative position of the sensor and the measuring target 20 is adjusted, specifically by sliding the second T-block. 42. Slide the first T-block 41 longitudinally to adjust the height of the lifting platform 40. After the height is adjusted to the correct position, tighten the first tightening knob 43 to fix the second T-block 42. Then slide the sensor fixing plate 50 laterally along the second T-block 42 to make the axis of the eddy current sensor 90 basically aligned with the axis of the measuring target 20. After alignment, tighten the second tightening knob 53 to fix the sensor fixing plate 50. At this time, observe the reading of the dial indicator body 70 to further confirm the positional accuracy of the sensor fixing plate 50. Finally, according to the instruction manual of the eddy current sensor 90, connect the preamplifier to the eddy current sensor 90 to be calibrated and connect the output line. Start the portable integrated vibrator 10. The vibrator 10 outputs a controllable vibration signal to drive the measuring target 20 to vibrate, and the dynamic calibration measurement operation of the eddy current sensor 90 can be carried out.

[0026] In this embodiment, the eddy current sensor 90 is fixed by setting an adapter window 81 on the sensor fixing plate 50 and cooperating with the third tightening knob 82. It can be adapted to sensors with various nominal probe diameters such as 5 mm, 8 mm and 16 mm and corresponding mounting thread specifications. At the same time, by adjusting the longitudinal height of the lifting platform 40 and the lateral position of the sensor fixing plate 50, the relative position of the sensor and the measuring target 20 can be flexibly adjusted. Combined with the precise positioning of the dial indicator, it can be ensured that sensors of different specifications can be accurately docked with the measuring target 20.

[0027] In this embodiment, the measurement target 20 is manually tightened and fixed to the moving rod of the vibrator 10 via a threaded structure. When the material of the actual measurement shaft changes, it is only necessary to disassemble the original measurement target 20 and replace it with a measurement target 20 made of the same material as the new measurement shaft, which significantly shortens the replacement cycle and reduces calibration costs. At the same time, the entire calibration device has a compact structure and uses a portable integrated vibrator 10, which eliminates the need to send the sensor to a professional location for calibration, enabling on-site calibration, further shortening the calibration cycle and reducing calibration time and transportation costs.

[0028] The calibration device in this embodiment has a simple overall structure. Each component is assembled and fixed by screws, slide rails, and tightening knobs, making assembly easy. The dynamic calibration operation process is clear, requiring only simple steps such as target fixing, base plate 30 assembly, sensor fixing, position adjustment, and wiring connection to carry out calibration work, without complicated operation procedures. At the same time, the position of the sensor fixing plate 50 is monitored in real time by a dial indicator. Combined with the precise adjustment structure of the lifting platform 40 and the sensor fixing plate 50, the precise alignment of the eddy current sensor 90 and the measurement target 20 can be ensured, improving the reliability and stability of calibration.

[0029] Please see Figure 2 and Figure 5 Based on the above embodiments, it is further proposed that the adapter window 81 is provided with two symmetrical surfaces 83 that are angled together on the side away from the third tightening knob 82. The eddy current sensor is centered by abutting against the two symmetrical surfaces 83. This structural design can quickly and accurately position the eddy current sensor 90 of different specifications to the center position of the adapter window 81 without the need for additional complex positioning fixtures, effectively avoiding the offset error that may be caused by manual adjustment of positioning.

[0030] Please see Figure 2-3Based on the above embodiments, a dial indicator mounting bracket 60 is further proposed, comprising a column 61 vertically mounted on a base plate 30 and a crossbar 62 vertically connected to the column 61. One end of the crossbar 62 extends directly above the sensor mounting plate 50. The dial indicator body is fixedly mounted at the extended end of the crossbar 62. The dial indicator body has a side rod assembly, which is connected to the sensor mounting plate 50. Both ends of the crossbar 62 are provided with connecting through holes 63, and the inner side of the connecting through holes 63 is provided with a pressure slit 64 penetrating the end of the crossbar 62. A fourth tightening knob 65 is threadedly connected to the crossbar 62 at the position corresponding to the toothed slot. The crossbar 62 is connected to the column 61 and the dial indicator body respectively through the two connecting through holes 63, and is fixedly engaged with the column 61 and the dial indicator body by tightening the fourth tightening knob 65. By connecting one end of the crossbar 62 to the through hole 63 and the column 61, and locking it with the fourth tightening knob 65, the height position of the crossbar 62 along the column 61 can be easily adjusted and it can be firmly fixed. By connecting the other end of the crossbar 62 to the through hole 63 and the dial indicator body, and locking it with the fourth tightening knob 65, the installation angle and horizontal position of the dial indicator body can be flexibly adjusted to ensure that the dial indicator side rod assembly can accurately align with the preset monitoring position of the sensor mounting plate 50. This structure is not only easy to assemble and disassemble, but also has high adjustment accuracy. It can adapt to the monitoring needs of different specifications of sensor mounting plates 50, effectively avoiding position monitoring errors caused by dial indicator installation misalignment, and further improving the accuracy of sensor positioning adjustment. At the same time, the cooperation between the pressure seam 64 and the fourth tightening knob 65 can achieve tight locking of the connection parts, preventing the dial indicator position from loosening due to the vibration of the vibrator 10 during calibration, ensuring the stability and continuity of position monitoring, and providing reliable monitoring guarantee for improving calibration accuracy.

[0031] It will be apparent to those skilled in the art that this invention is not limited to the details of the exemplary embodiments described above, and that it can be implemented in other specific forms without departing from the spirit or essential characteristics of this invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of this invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within this invention.

Claims

1. An eddy current sensor calibration device driven by an exciter, characterized by, Includes a calibration device fixedly mounted on the vibrator (10) and a measurement target (20) mounted on the moving rod of the vibrator (10). The calibration device includes a base plate (30) fixed on the vibrator (10), a lifting platform (40) mounted on the base plate (30), a sensor fixing plate (50) mounted on the lifting platform (40), a dial indicator fixing bracket (60) mounted on the base plate (30), and a dial indicator body (70) mounted on the dial indicator fixing bracket (60). The dial indicator body (70) acts on the sensor fixing plate (50). A sensor fixing structure (80) is provided on the sensor fixing plate (50). The sensor fixing structure (80) is used to fix the eddy current sensor (90) so that the eddy current sensor (90) is connected to the measurement target (20).

2. The eddy current sensor calibration device driven by a vibration exciter according to claim 1, wherein, A foot (31) is provided at each corner of the base plate (30), and a base plate fixing screw (32) is provided at each position of the foot (31) on the base plate (30).

3. The eddy current sensor calibration device driven by a vibration exciter according to claim 1, wherein The base plate (30) is a right-angled triangle structure, and a clearance opening (33) is provided at the middle position of the hypotenuse of the base plate (30). The measuring target (20) is located at the clearance opening (33).

4. The eddy current sensor calibration device driven by a vibration exciter according to claim 1, wherein The lifting platform (40) includes a first T-block (41) fixedly installed on the base plate (30) and a second T-block (42) slidably connected to the first T-block (41) in the longitudinal direction. A first tightening knob (43) is connected between the first T-block (41) and the second T-block (42). The first T-block (41) and the second T-block (42) are tightened and fixed by the first tightening knob (43).

5. The eddy current sensor calibration device driven by a vibration exciter according to claim 4, characterized in that, The first T-block (41) and the second T-block (42) both have vertical mating surfaces. The first T-block (41) and the second T-block (42) are respectively provided with a first sliding groove (44) and a first sliding rail (45) so that the first T-block (41) and the second T-block (42) slide together through the first sliding groove (44) and the first sliding rail (45). The first tightening knob (43) fixes the first T-block (41) and the second T-block (42) by passing through the first sliding groove (44) and abutting against the first sliding rail (45).

6. An eddy current sensor calibration device driven by a vibration exciter according to any one of claims 4-5, characterized in that, The upper end of the second T-block (42) and the lower end of the sensor fixing plate (50) are respectively provided with a second slide groove (51) and a second slide rail (52). The sensor fixing plate (50) is slidably connected to the second T-block (42) through the sliding cooperation of the second slide groove (51) and the second slide rail (52). A second tightening knob (53) is also connected to the sensor fixing plate (50). The second tightening knob (53) is used to abut against the second T-block (42). After the sensor fixing plate (50) is adjusted to a suitable position on the second T-block (42), the sensor fixing plate (50) and the second T-block (42) are fixed by tightening the second tightening knob (53).

7. The eddy current sensor calibration device driven by an exciter according to claim 1, characterized in that, The sensor fixing structure (80) includes an adapter window (81) opened on the sensor fixing plate (50) and a third tightening knob (82) threaded to one side of the sensor fixing plate (50). One end of the third tightening knob (82) extends into the adapter window (81) to longitudinally press the eddy current sensor (90) against the adapter window (81).

8. The eddy current sensor calibration device driven by an exciter according to claim 7, characterized in that, The adapter window (81) has two symmetrical surfaces (83) that fit together at an angle on the side away from the third tightening knob (82). The eddy current sensor is centered by abutting the two symmetrical surfaces (83).

9. The eddy current sensor calibration device driven by an exciter according to claim 1, characterized in that, The dial indicator mounting bracket (60) includes a column (61) mounted vertically on a base plate (30) and a crossbar (62) vertically connected to the column (61). One end of the crossbar (62) extends directly above the sensor mounting plate (50). The dial indicator body is fixedly mounted at the extended end of the crossbar (62). The dial indicator body has a side rod assembly, which is connected to the sensor mounting plate (50).

10. A calibration device for an eddy current sensor driven by an exciter according to claim 9, characterized in that, Both ends of the crossbar (62) are provided with connecting through holes (63), and the inner side of the connecting through holes (63) is provided with a pressure slit (64) that passes through the end of the crossbar (62). The crossbar (62) is threaded with a fourth tightening knob (65) at the position corresponding to the toothed slot. The crossbar (62) is connected to the column (61) and the dial indicator body through the two connecting through holes (63) respectively, and is fixedly engaged with the column (61) and the dial indicator body by tightening the fourth tightening knob (65).

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