A measuring device and method applicable to a displacement adjustment control system

Abstract

The present invention discloses a measuring device and method applicable to a displacement adjustment control system. The device includes a high-precision digital laser rangefinder, a support cylinder, and a measuring rod. The high-precision digital laser rangefinder is arranged at one end of the support cylinder. The measuring rod is slidably arranged in the support cylinder. The measuring rod is coaxially arranged with the high-precision digital laser rangefinder and the support cylinder. One end of the measuring rod is located inside the support cylinder, and the other end is connected to the sliding end of the component to be measured. The high-precision digital laser rangefinder is connected with a power supply and a signal acquisition box. The measuring device of the present invention is designed with high reliability, long service life, and the characteristics that each part can be separately disassembled, cleaned, repaired, and replaced. The high-precision digital laser measurement has high stability, high linearity, a wide measurement range, can accurately detect and calibrate the movement in a small range, has a good response degree for fast dynamic signal measurement, can resist high temperature, electromagnetic interference, vibration, and has a self-sealing characteristic. In addition, the high-precision digital laser measuring device has low power consumption.

Description

Technical Field

[0001] The present invention belongs to the technical field of technical transformation of LVDT measuring devices, and particularly relates to a measuring device and method applicable to a displacement adjustment control system; it is particularly applicable to the measurement of the opening degree of a steam turbine control valve. Background Art

[0002] LVDT displacement sensors are widely used in regulation (control) systems to measure the displacement state of equipment. The working principle of traditional LVDT displacement sensors applied to regulation (control) systems is the same as that of a slide rheostat, and they are used as voltage dividers to present the actual position of the measured equipment with the output of relative voltage.

[0003] The existing differential transformer structure design of LVDT displacement sensors determines the following problems:

[0004] 1. After the electronic ruler or the seal ages, impurities are likely to enter, causing the iron core to jam.

[0005] 2. The gas-water mixture or oil and grease will enter the LVDT interior along the sealing part, seriously affecting the contact resistance of the electric brush, causing the displayed numbers to keep jumping or even malfunctioning.

[0006] 3. FM interference and electrostatic interference may cause the communication display numbers of the linear displacement sensor to jump.

[0007] 4. The LVDT displacement sensor has poor high-temperature resistance, and the influence brought by temperature change will cause the iron core to jam, malfunction or be damaged.

[0008] 5. The larger the range of the LVDT displacement sensor, the relatively lower the linearity. When the sensor accuracy is reduced to a certain level, the measurement loses its meaning. Therefore, the LVDT displacement sensor is suitable for micro-displacement precision measurement occasions and is rarely used for large-range displacement measurement.

[0009] 6. Due to the large inertia, low frequency response and large loss of the iron core of the LVDT displacement sensor, the response degree for measuring fast dynamic signals is poor. Summary of the Invention

[0010] In order to solve the problems existing in the prior art, the present invention provides a new LVDT measuring device applicable to a regulation (control) system, which solves problems such as high temperature, jamming and display error faced by the existing LVDT measuring device, effectively solves the high failure rate, improves the reliability of the device, extends the service life of the LVDT measuring device, and thus improves the drawback of frequent replacement of the LVDT measuring device.

[0011] To achieve the above object, the technical solution adopted by the present invention is: a measuring device applicable to a displacement adjustment control system, comprising a high-precision digital laser rangefinder, a support cylinder, and a measuring rod. The high-precision digital laser rangefinder is arranged at one end of the support cylinder, and the measuring rod is slidably arranged in the support cylinder. The measuring rod is coaxially arranged with the high-precision digital laser rangefinder and the support cylinder. One end of the measuring rod is located inside the support cylinder, and the other end is connected to the sliding end of the component to be measured; the high-precision digital laser rangefinder is connected with a power supply and a signal acquisition box.

[0012] A laser reflector is arranged at one end of the measuring rod located inside the support cylinder. Guide wheels are arranged at the edge of the laser reflector, and the guide wheels are in rolling contact with the inner wall of the support cylinder; a threaded cover is arranged at the end face of the support cylinder, and a through hole is opened at the center of the threaded cover. A sliding copper sleeve is arranged at the through hole, and the measuring rod passes through the sliding copper sleeve.

[0013] A gap is provided between the sliding copper sleeve and the measuring rod or between the threaded cover and the sliding copper sleeve.

[0014] The sides of two support cylinders are communicated through an air pipe, and the air pipe is connected to a slightly positive pressure air source.

[0015] The high-precision digital laser rangefinder is also connected with a UPS power supply, and the UPS power supply is connected to the plant power supply.

[0016] A limiting block is arranged on the inner wall of one end of the support cylinder close to the high-precision digital laser rangefinder.

[0017] Two groups are arranged in parallel. Two measuring rods are connected to a linkage measuring rod bottom plate, and the linkage measuring rod bottom plate is connected to the sliding end of the component to be measured.

[0018] The support cylinder is arranged on the equipment foundation or a structural component connected to the equipment foundation.

[0019] Based on the measuring method of the device of the present invention, during operation, the high-precision digital laser rangefinder is powered on. The sliding end of the component to be measured drives the measuring rod to slide in the support cylinder, which drives the distance between the laser measuring surface and the high-precision digital laser rangefinder to change. The high-precision digital laser rangefinder measures the distance and feeds back the signal to the signal acquisition box.

[0020] It is used to measure the opening of the steam turbine governing valve, and the end face of the linkage measuring rod is connected to the stroke mechanism of the valve.

[0021] Compared with the prior art, the present invention has at least the following beneficial effects: The measuring device of the present invention has high reliability and long service life, and each part can be separately disassembled, cleaned, repaired and replaced; The high-precision digital laser measurement adopted has high stability, high linearity, wide measurement range, can accurately detect and calibrate the movement in a small range, and has low power consumption and good responsiveness to fast dynamic signal measurement. It has good effects of resisting high temperature, electromagnetic interference and vibration, and has self-sealing characteristics.

[0022] Furthermore, an uninterruptible power supply (UPS) is installed at the same time, and the equipment has high stability during continuous operation, which can meet the continuous power supply after the equipment is powered off. The linkage double-insurance setting can effectively ensure the stability of the output data (measurement value) of the equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 It is a schematic diagram of a new type of LVDT measuring device applicable to an adjustment (control) system.

[0024] In the figure: 1. High-precision digital laser rangefinder; 2. LVDT mounting plate; 3. Threaded cap; 4. Linkage measuring rod bottom plate; 5. Limit block; 6. Uninterruptible power supply (UPS); 7. Laser measurement surface; 8. Sliding copper sleeve; 9. Signal acquisition box; 10. 220V to 24V voltage converter; 11. Micro positive pressure air injection port; 12. Support cylinder. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0025] The present invention will be further described in detail below with reference to the drawings and embodiments. It can be understood that the specific embodiments described herein are only used to explain the relevant content and do not limit the present invention. In addition, it should be noted that only the parts related to the present invention are shown in the drawings for the convenience of description.

[0026] It should be noted that, without conflict, the embodiments in the present invention and the features in the embodiments can be combined with each other. The technical solutions of the present invention will be described in detail below with reference to the drawings and embodiments.

[0027] Unless otherwise specified, the exemplary embodiments / Examples shown will be understood to provide various details of exemplary features of some ways that can implement the technical concept of the present invention in practice. Therefore, unless otherwise specified, the features of various embodiments / Examples can be additionally combined, separated, interchanged and / or rearranged without departing from the technical concept of the present invention.

[0028] In the drawings, the use of cross-hatching and / or shading is generally used to make the boundaries between adjacent components clear. Thus, unless otherwise stated, the presence or absence of cross-hatching or shading does not convey or imply any preference or requirement for the specific material, material properties, dimensions, proportions, commonality between the components shown, and / or any other characteristics, attributes, properties, etc. of the components. In addition, in the drawings, for clarity and / or descriptive purposes, the dimensions and relative dimensions of components may be exaggerated. When exemplary embodiments can be implemented differently, the specific process sequences may be performed in an order different from that described. For example, two consecutively described processes may be performed substantially simultaneously or in an order opposite to that described. In addition, the same reference numerals denote the same components.

[0029] When a component is referred to as being "on" or "above" another component, "connected to" or "coupled to" another component, the component may be directly on the other component, directly connected to or directly coupled to the other component, or there may be intermediate components. However, when a component is referred to as being "directly on" another component, "directly connected to" or "directly coupled to" another component, there are no intermediate components. For this reason, the term "connected" may refer to a physical connection, an electrical connection, etc., and may or may not have intermediate components.

[0030] The present invention provides a measuring device applicable to an adjustment (control) system to replace the original LVDT measuring device; the specific solution adopted is: including a high-precision digital laser rangefinder 1, a support cylinder, and a measuring rod. The high-precision digital laser rangefinder 1 is arranged at one end of the support cylinder, the measuring rod is slidably arranged in the support cylinder, the measuring rod is coaxially arranged with the high-precision digital laser rangefinder 1 and the support cylinder, one end of the measuring rod is located inside the support cylinder, and the other end is connected to the sliding end of the component to be measured; the high-precision digital laser rangefinder 1 is connected to a power supply and a signal acquisition box 9; a laser reflector is arranged at one end of the measuring rod located inside the support cylinder, guide wheels are arranged at the edge of the laser reflector, and the guide wheels are in rolling contact with the inner wall of the support cylinder; a threaded cover 3 is arranged on the end face of the support cylinder, a through hole is opened in the center of the threaded cover 3, and a sliding copper sleeve 8 is arranged at the through hole, and the measuring rod passes through the sliding copper sleeve 8.

[0031] A limiting block 5 is arranged on the inner wall of one end of the support cylinder 12 close to the high-precision digital laser rangefinder 1, and a plurality of the limiting blocks 5 can be arranged along the inner wall of the support cylinder 12 for one week.

[0032] Two sets of the above devices of the present invention are arranged in parallel, two measuring rods are connected to a linkage measuring rod bottom plate 4, and the linkage measuring rod bottom plate 4 is connected to the sliding end of the component to be measured; the linkage measuring rod bottom plate 4 is a rigid plate. Of course, in applicable cases, the linkage measuring rod bottom plate 4 can also be replaced by a rigid rod.

[0033] Air holes are formed in the barrel walls of the two support barrels. The air holes are connected through an air pipe, and the air pipe is connected to a slightly positive pressure air source. Compressed air enters the support barrel 12 from the slightly positive pressure air injection port 11 and flows out from the gap between the measuring rod and the sliding copper sleeve 8, forming a relatively sealed space, which can cool the device and protect the internal environment from being polluted by fine dust.

[0034] The support barrel is arranged on the equipment foundation or on the structural components connected to the equipment foundation. For measuring the opening of the steam turbine governing valve, the present invention preferably arranges the support barrel 12 on the LVDT mounting plate 2 without removing the original LVDT mounting plate 2.

[0035] Based on the measuring method of the device of the present invention, during operation, the high-precision digital laser rangefinder 1 is powered on. The sliding end of the component to be measured drives the measuring rod to slide in the support barrel, and the distance between the laser measuring surface and the high-precision digital laser rangefinder 1 changes as the measuring rod moves. The high-precision digital laser rangefinder 1 measures the distance and feeds back the signal to the signal acquisition box 9.

[0036] Preferably, the device and method of the present invention are used to measure the opening of the steam turbine governing valve, and the end face of the linkage measuring rod is connected to the stroke mechanism of the valve; it can realize timely and accurate measurement of the opening of the steam turbine governing valve, and the linkage double insurance setting can effectively ensure the stability of the data (measurement value) output by the device.

[0037] Using high-precision digital laser ranging technology, adopting the guiding (sliding) wheel replacement technology structure; improving the disadvantages of the existing LVDT. The present invention aims to solve the problems such as high temperature, jamming and display error faced by the existing LVDT measuring device, effectively solve the high failure rate, improve the reliability of the device, extend the service life of the LVDT measuring device, and thus improve the disadvantage of frequent replacement of the LVDT measuring device; high reliability, long service life, each part can be disassembled, cleaned, repaired and replaced separately; high-precision digital laser measurement has high stability, high linearity, wide measurement range, can accurately detect and calibrate the movement in a small range, and has a good response degree for rapid dynamic signal measurement; has good anti-high temperature, anti-electromagnetic interference and anti-vibration effects, and has a self-sealing characteristic; the high-precision digital laser measuring device has low power consumption. At the same time, a 6-hour power supply UPS is installed, and the continuous operation stability of the equipment is high, which can meet the continuous power supply after the equipment is powered off.

[0038] A laser reflector is arranged at one end of the measuring rod located in the support barrel 12. The measuring rod is connected to the center of the laser reflector, and guide wheels are arranged at the edge of the laser reflector. The guide wheels are in rolling contact with the inner wall of the support barrel; a threaded cover 3 is arranged at the end face of the support barrel, a through hole is formed in the center of the threaded cover 3, and a sliding copper sleeve 8 is arranged at the through hole. The measuring rod passes through the sliding copper sleeve 8.

[0039] A plurality of guide wheels are arranged around the laser reflector. The guide wheels adopt bearings. A plurality of openings are arranged along the circumference at the edge of the laser reflector, and the guide wheels are arranged at the openings.

[0040] As an optional embodiment, two sets of the above-mentioned guide wheels and the laser reflector are arranged along the axial direction of the measuring rod, so that the measuring rod can better maintain axial movement.

[0041] Optionally, the laser reflector has a certain thickness. A plurality of ball socket structures are arranged around the laser reflector, and balls are arranged in the ball socket structures. The balls are in rolling contact with the inner wall of the support cylinder.

[0042] As Figure 1 shown, a new type of measuring device applicable to an adjustment (control) system according to the present invention: install the LVDT mounting plate 2 at a fixed position, and install the linkage measuring rod bottom plate 4 on the stroke mechanism of the valve; during operation, connect the 220V power supply, pass through the 220V to 24V voltage converter 10, and enter the high-precision digital laser rangefinder 1 through the 6-hour UPS power supply; determine the 0%-100% stroke of the measurement through the laser measurement surface + the upper dead point limit block 5 of the guide wheel 7 or the pulley and the lower dead point sliding copper sleeve 8; the upper dead point and the lower dead point are respectively at the limit block 5 and the sliding copper sleeve 8, and the feedback signal enters the signal acquisition box 9 and is combined with remote transmission; inject slightly positive pressure compressed air through the slightly positive pressure air injection port 11 to play a role in sealing and cooling, and ensure the normal use of the measuring device at high temperatures.

Claims

1. A measuring device applicable to a displacement adjustment control system, characterized in that, It includes a high-precision digital laser rangefinder (1), a support cylinder (12), and a measuring rod. The high-precision digital laser rangefinder (1) is arranged at one end of the support cylinder (12). The measuring rod is slidably arranged in the support cylinder (12). The measuring rod is coaxially arranged with the high-precision digital laser rangefinder (1) and the support cylinder (12). One end of the measuring rod is located inside the support cylinder (12), and the other end is connected to the sliding end of the component to be measured. The high-precision digital laser rangefinder (1) is connected with a power supply and a signal acquisition box (9). A laser reflector is arranged at one end of the measuring rod located inside the support cylinder (12). Guide wheels are arranged at the edge of the laser reflector, and the guide wheels are in rolling contact with the inner wall of the support cylinder (12). A threaded cover (3) is arranged at the end face of the support cylinder (12). A through hole is opened at the center of the threaded cover (3), and a sliding copper sleeve (8) is arranged at the through hole. The measuring rod passes through the sliding copper sleeve (8). There is a gap between the sliding copper sleeve (8) and the measuring rod or between the threaded cover (3) and the sliding copper sleeve (8). The sides of two support cylinders (12) are connected through an air pipe, and the air pipe is connected to a slightly positive pressure air source. Two sets of the above structures are arranged in parallel. Two measuring rods are connected to a linkage measuring rod bottom plate (4), and the linkage measuring rod bottom plate (4) is connected to the sliding end of the component to be measured.

2. The measuring device applicable to the displacement adjustment control system according to claim 1, characterized in that, The high-precision digital laser rangefinder (1) is also connected with a UPS power supply, and the UPS power supply is connected to the plant power supply.

3. The measuring device applicable to the displacement adjustment control system according to claim 1, characterized in that A limit block (5) is arranged on the inner wall of the support cylinder (12) near the high-precision digital laser rangefinder (1).

4. The measuring device applicable to the displacement adjustment control system according to claim 1, characterized in that, The support cylinder (12) is arranged on the equipment foundation or a structural component connected to the equipment foundation.

5. A measurement method based on the device according to any one of claims 1 to 4, characterized in that During operation, power is supplied to the high-precision digital laser rangefinder (1). The sliding end of the component to be measured drives the measuring rod to slide in the support cylinder (12). The measuring rod drives the distance between the laser measuring surface and the high-precision digital laser rangefinder (1) to change. The high-precision digital laser rangefinder (1) measures the distance and feeds back the signal to the signal acquisition box (9).

6. Use of the device according to any one of claims 1 to 4, characterized in that, It is used to measure the opening of the steam turbine governing valve, and the end face of the linkage measuring rod is connected to the stroke mechanism of the valve.

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