阅读说明：本技术 一种利用霍尔元件实现自动调零功能的涡流探头及其控制方法 (Eddy current probe for realizing automatic zero adjustment function by utilizing Hall element and control method thereof ) 是由 田中山 王现中 杨昌群 牛道东 李育特 于 2021-09-09 设计创作，主要内容包括：本发明提出一种利用霍尔元件实现自动调零功能的涡流探头及其控制方法：探头包括霍尔元件,激励线圈,数控移相器,相位差测量电路,幅值测量电路,控制器,数控幅值调节器,调零触发电路,参考件和减法器；只需要一个霍尔元件就可实现探头的调零功能,避免了采用两个霍尔元件,要求参数一致的问题,同时也提高了电涡流探头调零的精度及探头输出信号的动态范围,线性测量范围便变大；电涡流探头采用霍尔元件作为检测元件,灵敏度和分辨率都得到了提高,对于低频工作范围也更加适用；在检测调零过程中不再需要参考件,在检测大型的零件、设备以及需要探头尺寸较小的场合也极为方便。(The invention provides an eddy current probe for realizing an automatic zero adjustment function by utilizing a Hall element and a control method thereof, wherein the eddy current probe comprises the following steps: the probe comprises a Hall element, an exciting coil, a numerical control phase shifter, a phase difference measuring circuit, an amplitude measuring circuit, a controller, a numerical control amplitude regulator, a zero setting trigger circuit, a reference piece and a subtracter; the zero setting function of the probe can be realized only by one Hall element, the problem that two Hall elements are adopted and the parameters are required to be consistent is avoided, the zero setting precision of the eddy current probe and the dynamic range of the output signal of the probe are improved, and the linear measurement range is enlarged; the eddy current probe adopts the Hall element as a detection element, so that the sensitivity and the resolution are improved, and the eddy current probe is more suitable for a low-frequency working range; the zero setting detection device does not need a reference part in the zero setting detection process, and is very convenient for detecting large parts and equipment and occasions requiring small probe size.)

1. The utility model provides an utilize hall element to realize eddy current probe of autozero function which characterized in that:

the probe comprises a Hall element, an exciting coil, a numerical control phase shifter, a phase difference measuring circuit, an amplitude measuring circuit, a controller, a numerical control amplitude regulator, a zero setting trigger circuit, a reference piece and a subtracter;

the Hall element is fixed at the bottom end of the exciting coil;

the exciting coil, the numerical control phase shifter, the numerical control amplitude regulator and the subtracter are sequentially connected; the Hall element is respectively connected with the phase difference measuring circuit and the amplitude measuring circuit; the phase difference measuring circuit is connected with the controller; the amplitude measuring circuit is respectively connected with the controller and the subtracter; the controller is respectively connected with the numerical control phase shifter and the numerical control amplitude regulator; the reference piece, the zero setting trigger circuit and the controller are connected in sequence.

2. A control method of an eddy current probe applied to an automatic zero setting function is characterized in that:

s1: placing the probe on a reference piece, and triggering the probe to zero by a zero setting triggering circuit;

s2: the amplitude measuring circuit measures the amplitude of the output signal of the Hall element, and the phase difference measuring circuit measures the phase difference between the output signal of the Hall element and the excitation signal of the probe;

s3: the measurement result is processed by a controller, and parameters of the phase shift circuit and the amplitude adjusting circuit are determined;

s4: enabling the probe excitation signal to sequentially pass through a numerical control phase shifter and a numerical control amplitude regulator, thereby obtaining a signal which is completely consistent with the amplitude and the phase of the output signal of the Hall element, and taking the obtained signal as a reference signal for probe zero setting;

s5: and taking the difference between the output signal of the Hall element and the reference signal as the final output signal of the probe.

3. The method of claim 2, further comprising:

the probe completes zero setting before formal detection, and a reference piece is not needed in the formal detection process.

Technical Field

The invention belongs to the field of eddy current detection, and particularly relates to an eddy current probe for realizing an automatic zero setting function by utilizing a Hall element and a control method thereof.

Background

The eddy current sensor is a traditional non-contact type measuring and sensing device, has excellent characteristics of nondestructive testing, high sensitivity, high response speed, strong anti-interference capability and the like, and is widely applied to displacement measurement, defect detection and device operation state monitoring in various fields such as industrial production and the like. However, the current eddy current sensor is limited by technical bottlenecks such as optimization of coil structural parameters, innovative design of a detection circuit, dynamic compensation of measurement errors and the like, and has the prominent limitations of poor sensitivity, poor linearity, poor temperature interference resistance and the like, so that the current eddy current sensor is directly limited to popularization and application in the high-precision detection field in various extreme environments.

In defect detection, not only the sensitivity of the eddy current probe needs to be improved, but also the dynamic output range of the eddy current probe needs to be improved, that is, the probe needs to be zeroed. In defect detection, the signals generated by the conductive structures of the multiple layers and the edges themselves are mostly large, and the defect signals are buried. At present, most of eddy current probes generally adopt double sensors to realize the zero adjustment function in a differential connection mode, and the method has a simple structure, is quick and effective, and also enables the differential zero adjustment type probe to be widely applied.

However, the method of achieving zero adjustment by adopting a dual-sensor differential mode has certain defects, and firstly, parameters of two sensors need to be ensured to be consistent, so that high requirements are provided for processing and manufacturing the sensors; secondly, a dual-sensor differential connection mode zero setting probe is adopted, a reference piece is needed in the zero setting detection process, and therefore the zero setting detection device is inconvenient in detecting large parts and equipment and occasions needing small probe sizes.

Disclosure of Invention

Aiming at the defects of the existing method, the invention provides the eddy current probe which utilizes the Hall element to realize the automatic zero adjustment function, only has high sensitivity, simultaneously has the automatic zero adjustment function, has a large linear measurement range, can realize the distance measurement and the nondestructive detection of deep defects, and can be applied to the fields of aerospace, processing and manufacturing, pipeline transportation and the like. .

The invention is realized by the following method:

an eddy current probe for realizing an automatic zero setting function by utilizing a Hall element comprises:

the probe comprises a Hall element, an exciting coil, a numerical control phase shifter, a phase difference measuring circuit, an amplitude measuring circuit, a controller, a numerical control amplitude regulator, a zero setting trigger circuit, a reference piece and a subtracter;

the Hall element is fixed at the bottom end of the exciting coil;

the exciting coil, the numerical control phase shifter, the numerical control amplitude regulator and the subtracter are sequentially connected; the Hall element is respectively connected with the phase difference measuring circuit and the amplitude measuring circuit; the phase difference measuring circuit is connected with the controller; the amplitude measuring circuit is respectively connected with the controller and the subtracter; the controller is respectively connected with the numerical control phase shifter and the numerical control amplitude regulator; the reference piece, the zero setting trigger circuit and the controller are connected in sequence.

A control method of an eddy current probe applied to an automatic zero setting function comprises the following steps:

s1: placing the probe on a reference piece, and triggering the probe to zero by a zero setting triggering circuit;

s2: the amplitude measuring circuit measures the amplitude of the output signal of the Hall element, and the phase difference measuring circuit measures the phase difference between the output signal of the Hall element and the excitation signal of the probe;

s3: the measurement result is processed by a controller, and parameters of the phase shift circuit and the amplitude adjusting circuit are determined;

s4: enabling the probe excitation signal to sequentially pass through a numerical control phase shifter and a numerical control amplitude regulator, thereby obtaining a signal which is completely consistent with the amplitude and the phase of the output signal of the Hall element, and taking the obtained signal as a reference signal for probe zero setting;

s5: and taking the difference between the output signal of the Hall element and the reference signal as the final output signal of the probe.

Furthermore, the probe is zeroed before formal detection, and a reference piece is not needed in the formal detection process.

The invention has the beneficial effects

(1) The invention can realize the zero setting function of the probe only by one Hall element, thus avoiding the problem that two Hall elements are adopted and the parameters are required to be consistent, simultaneously improving the zero setting precision of the eddy current probe and the dynamic range of the output signal of the probe, and enlarging the linear measurement range;

(2) the eddy current probe adopts the Hall element as a detection element, so that the sensitivity and the resolution are improved, and the eddy current probe is more suitable for a low-frequency working range;

(3) the Hall element magnetic field sensor has the advantages of firm structure, small volume, light weight, long service life, convenient installation, low power consumption, high frequency, vibration resistance, corrosion resistance, excellent sensitivity and other properties;

(4) the zero setting detection device does not need a reference part in the zero setting detection process, and is very convenient for detecting large parts and equipment and occasions requiring small probe size.

Drawings

Fig. 1 is a schematic view of the operation mode of the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments; all other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

An eddy current probe for realizing an automatic zero setting function by utilizing a Hall element comprises the Hall element, an exciting coil, a numerical control phase shifter, a phase difference measuring circuit, an amplitude measuring circuit, a controller, a numerical control amplitude regulator, a zero setting trigger circuit, a reference part and a subtracter;

the Hall element is fixed at the bottom end of the exciting coil;

the exciting coil, the numerical control phase shifter, the numerical control amplitude regulator and the subtracter are sequentially connected; the Hall element is respectively connected with the phase difference measuring circuit and the amplitude measuring circuit; the phase difference measuring circuit is connected with the controller; the amplitude measuring circuit is respectively connected with the controller and the subtracter; the controller is respectively connected with the numerical control phase shifter and the numerical control amplitude regulator; the reference piece, the zero setting trigger circuit and the controller are connected in sequence.

A control method of an eddy current probe applied to an automatic zero setting function comprises the following steps:

s1: placing the probe on a reference piece, and triggering the probe to zero by a zero setting triggering circuit;

s2: the amplitude measuring circuit measures the amplitude of the output signal of the Hall element, and the phase difference measuring circuit measures the phase difference between the output signal of the Hall element and the excitation signal of the probe;

s3: the measurement result is processed by a controller, and parameters of the phase shift circuit and the amplitude adjusting circuit are determined;

s4: enabling the probe excitation signal to sequentially pass through a numerical control phase shifter and a numerical control amplitude regulator, thereby obtaining a signal which is completely consistent with the amplitude and the phase of the output signal of the Hall element, and taking the obtained signal as a reference signal for probe zero setting;

s5: and taking the difference between the output signal of the Hall element and the reference signal as the final output signal of the probe.

The zero setting function of the probe can be realized only by one Hall element, so that the problem that two Hall elements are adopted and parameters are required to be consistent is avoided, the zero setting precision of the eddy current probe and the dynamic range of output signals of the probe are improved, and the linear measurement range is enlarged. The eddy current probe adopts the Hall element as a detection element, so that the sensitivity and the resolution are improved, and the eddy current probe is more suitable for a low-frequency working range. The zero setting detection device does not need a reference part in the zero setting detection process, and is very convenient for detecting large parts and equipment and occasions requiring small probe size.

The eddy current probe for realizing the automatic zero adjustment function by using the hall element, which is proposed by the present invention, is introduced in detail, the principle and the implementation mode of the present invention are explained, and the above description of the embodiment is only used for helping to understand the method and the core idea of the present invention; meanwhile, for a person skilled in the art, according to the idea of the present invention, there may be variations in the specific embodiments and the application scope, and in summary, the content of the present specification should not be construed as a limitation to the present invention.