CN1038347A - The interchanger that is used for sound-emission signal recording - Google Patents

Abstract

Translated fromChinese

本变换器包括外壳1、外壳1中装的预放大器7、与预放大器电气连接的圆柱形压电元件5、在压电元件上与其同轴安装的圆盘形保护部件4和阻尼元件6.变换器附加装有与压电元件5同轴地安装在外壳1的底部2上的套筒3，以螺纹方式与2连接，保护部件装在挨着外壳1的底部2的外表面的套筒3的端部，阻尼元件6呈杯状且安装在套筒3中以螺纹方式连接，还包围着用以实现压电元件5与预放大器的电耦合的机构8的布置区域内的压电元件。

The converter includes a housing 1, a pre-amplifier 7 installed in the housing 1, a cylindrical piezoelectric element 5 electrically connected to the pre-amplifier, a disc-shaped protective component 4 coaxially installed on the piezoelectric element and a damping element 6. The converter is additionally equipped with a sleeve 3 coaxially installed on the bottom 2 of the shell 1 with the piezoelectric element 5 and connected with 2 in a threaded manner, and the protective part is mounted on the sleeve adjacent to the outer surface of the bottom 2 of the shell 1 3 , the damping element 6 is cup-shaped and mounted in the sleeve 3 to be screwed together, also enclosing the piezoelectric element in the area of arrangement of the mechanism 8 for the electrical coupling of the piezoelectric element 5 and the preamplifier.

Description

Translated fromChinese

本发明涉及无损检测领域，具体涉及用于声发射信号记录的变换器。The invention relates to the field of non-destructive testing, in particular to a transducer for acoustic emission signal recording.

本发明最适用于声发射装置，这些装置既可用来检验焊缝的质量，又可用来检验机械制造业、建筑业和其它部门使用的主要的结构材料的完整性。The present invention is most applicable to acoustic emission devices which are used both for inspecting the quality of welds and for inspecting the integrity of primary structural materials used in machine building, construction and other sectors.

已知的用于声发射信号记录的变换器包括外壳，在外壳的底部同轴地设置一圆盘形保护部件，在该部件上同轴地紧固一呈圆柱形的压电元件，外壳内还设有阻尼元件和预放大器，该预放大器与压电元件电气连接，阻尼元件呈垫圈形式，被安装在外壳的底部，并与圆盘形保护部件同轴（B.A.

peulHuHol等，“声发射”，1976年，标准出版社，（莫斯科），第75页）。The known transducer for acoustic emission signal recording comprises a housing, a disc-shaped protective part is coaxially arranged at the bottom of the housing, a cylindrical piezoelectric element is fastened coaxially on the part, and inside the housing There is also a damping element, electrically connected to the piezoelectric element, and a pre-amplifier, the damping element being in the form of a washer, mounted on the bottom of the housing and coaxial with the disc-shaped protective part (BA

peulHuHol et al., "Acoustic Emission", 1976, Standard Press, (Moscow), p. 75).

该用于声发射信号记录的变换器与众所周知的这种类型的变换器相比较，该变换器能记录频带更宽的声发射信号。但是在其结构中只采用了尺寸型式单一的压电元件，因此当检测几何尺寸不同且超声波传播特性不同的结构时，它的应用受到了限制。由于压电元件牢固地固定在圆盘形保护部件上，致使运行可靠性相对地不高，并因其焊接成的接点的电接触性易损坏而缺乏抗冲击性，以及当该变换器失落时，会使压电元件的电极脱落。The transducer for the recording of acoustic emission signals is capable of recording acoustic emission signals of a wider frequency band than known transducers of this type. However, only piezoelectric elements with a single size and type are used in its structure, so its application is limited when detecting structures with different geometric dimensions and different ultrasonic propagation characteristics. Due to the fact that the piezoelectric element is firmly fixed on the disc-shaped protective part, the operating reliability is relatively low, and the electrical contact of the soldered joints is easily damaged, lacking shock resistance, and when the transducer is dropped , the electrodes of the piezoelectric element will fall off.

此外，阻尼元件的这种结构形式不可能改变压电元件的阻尼程度，而能够变换压电元件的阻尼程度在选择变换器的最佳工作频带及其灵敏度时是很重要的;还不可能得到圆方向性图。In addition, this structural form of the damping element is impossible to change the damping degree of the piezoelectric element, and it is very important to be able to change the damping degree of the piezoelectric element when selecting the optimum operating frequency band of the converter and its sensitivity; it is not possible to obtain Circular Directional Diagram.

本发明的任务是提供一种具有这样结构形式的用于声发射信号记录的变换器，它能够保证被记录的信号具有较高的质量，使扩展缺陷的坐标测量具有较高的准确度，还提高了变换器的灵敏度，从而提高其运行可靠性及寿命。The task of the present invention is to provide a transducer for acoustic emission signal recording with such a structural form, which can ensure that the recorded signal has a higher quality, so that the coordinate measurement of the extended defect has a higher accuracy, and also The sensitivity of the converter is improved, thereby improving its operational reliability and life.

上述任务是这样解决的：用于声发射信号记录的变换器包括外壳，外壳中设置预放大器，它与呈圆柱形的压电元件电气连接，压电元件同轴地安装在圆盘形保护部件上，还包括阻尼元件，根据本发明，该阻尼元件带有套筒，该套筒与压电元件同轴安装在外壳的底部，并且通过螺纹连接的方式与后者相连接，同时圆盘形保护部件位于套筒的端部，挨着外壳底部的外表面，而阻尼元件呈杯状，安装在套筒中，两者以螺纹连接的方式连接，并且阻尼元件包围着用来实现压电元件同预放大器之间的电耦合的机构的布置区域内的压电元件。The above-mentioned tasks are solved as follows: the transducer for acoustic emission signal recording comprises a housing in which a pre-amplifier is arranged, which is electrically connected to a cylindrical piezoelectric element coaxially mounted on a disc-shaped protective part It also includes a damping element, according to the present invention, the damping element has a sleeve, the sleeve is installed coaxially with the piezoelectric element on the bottom of the housing, and is connected to the latter by screwing, while the disc-shaped The protective part is located at the end of the sleeve, close to the outer surface of the bottom of the housing, and the damping element is cup-shaped and installed in the sleeve. The piezoelectric element is placed within the area of the mechanism for the electrical coupling between the pre-amplifiers.

适宜的是，用以实现压电元件与预放大器的电耦合的机构包括接触盘和心线，该接触盘位于压电元件的自由端，该心线穿过设于阻尼杯底部的孔，其一端牢固地连接在接触盘上，而另一端与预放大器电气连接。Suitably, the mechanism for realizing the electrical coupling between the piezoelectric element and the pre-amplifier includes a contact disk and a core wire, the contact disk is located at the free end of the piezoelectric element, and the core wire passes through a hole provided at the bottom of the damping cup, which One end is firmly connected to the contact pad, while the other end is electrically connected to the preamplifier.

这种结构形式的用以实现电耦合的机构使压电元件与预放大器的电耦合很可靠，因为这可以避免压电元件和预放大器之间电极的刚性接触。The means for realizing the electrical coupling in this form of construction make the electrical coupling of the piezo element to the preamplifier reliable, since this prevents a rigid contact of the electrodes between the piezo element and the preamplifier.

根据本发明，用于声放发射信号记录的变换器可以调节阻尼的大小，因此可以使声发射信号变换器的振幅频率响应特性在给定的频带及在所要求的灵敏度的条件下达到均匀一致，而且具有较高的准确度。此外，所推荐的变换器保证能有效地接收声发射信号，并可提高可靠性和灵敏度，还可以减少所使用的变换器的数量。所推荐的变换器的结构形式可大大地提高维修方便性和缩短装配时间。According to the present invention, the converter used for acoustic emission signal recording can adjust the size of the damping, so the amplitude frequency response characteristics of the acoustic emission signal converter can be made uniform in a given frequency band and under the condition of required sensitivity , and has high accuracy. In addition, the proposed transducer ensures effective reception of acoustic emission signals, improves reliability and sensitivity, and reduces the number of transducers used. The proposed structure of the converter can greatly improve the convenience of maintenance and shorten the assembly time.

下面参照附图详细地说明本发明的具体实施例，附图概括地表示了按照本发明实施的用于声发射信号记录的变换器。Specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings, which generally show a transducer for acoustic emission signal recording implemented according to the present invention.

实施本发明的最佳实施例的用于声发射信号记录的变换器包括外壳1，在外壳的底部2上装有套筒3。套筒3与外壳1以螺纹连接方式连接。在挨着外壳1的底部2的外表面的套筒3的端部装有圆盘形保护部件4，在该保护部件上通过接触液层同轴安装着圆柱形的压电元件5，而且该压电元件相对于套筒3是同轴的。A transducer for recording acoustic emission signals embodying a preferred embodiment of the invention comprises a housing 1 on the bottom 2 of which is fitted a sleeve 3 . The sleeve 3 is connected with the shell 1 in a threaded manner. At the end of the sleeve 3 next to the outer surface of the bottom 2 of the housing 1 is fitted a disc-shaped protective part 4 on which a cylindrical piezoelectric element 5 is mounted coaxially through a contact liquid layer, and the The piezoelectric element is coaxial with respect to the sleeve 3 .

借助于阻尼元件6来实现压电元件5的阻尼。阻尼元件6呈杯状（以下简称阻尼杯6），它被安装在套筒3中，以螺纹连接方式与套筒连接，并且包围着压电元件5。Damping of piezoelectric element 5 is achieved by means of damping element 6 . The damping element 6 is in the shape of a cup (hereinafter referred to as the damping cup 6 ), which is installed in the sleeve 3 , is connected with the sleeve in a threaded manner, and surrounds the piezoelectric element 5 .

在外壳1内装有预放大器7，该预放大器通过机构8与压电元件5电气连接。用来实现压电元件5与预放大器7的电耦合的机构8包括位于压电元件5的自由端的接触盘9和心线10。心线10穿过阻尼杯6的底部上的孔11，其一端牢固地连接在接触盘9上，而另一端与预放大器7电气连接。Apreamplifier 7 is installed in the housing 1 and is electrically connected to the piezoelectric element 5 via a mechanism 8 . The means 8 for the electrical coupling of the piezoelectric element 5 to thepreamplifier 7 comprise a contact disc 9 and a core 10 at the free end of the piezoelectric element 5 . The core wire 10 passes through the hole 11 on the bottom of the damping cup 6 , one end of which is firmly connected to the contact plate 9 , and the other end is electrically connected to the pre-amplifier 7 .

外壳1有盖子12和接头13。The housing 1 has acover 12 and aconnector 13 .

接收声发射信号的变换器的工作情况如下：The working condition of the converter receiving the acoustic emission signal is as follows:

当有缺陷时，所引起的声发射信号在被检测的对象（图中未示出）中传播。这些信号经过圆盘形的保护部件4到达压电元件5，并被转变成电信号。然后电信号由压电元件5经过接触盘9和牢固地固定在接触盘上的心线10到达预放大器7，并被接收器（图中未示出）记录下来。When there is a defect, the resulting acoustic emission signal propagates in the object being inspected (not shown in the figure). These signals pass through the disk-shaped protective member 4 to the piezoelectric element 5 and are converted into electrical signals. Then the electric signal reaches the pre-amplifier 7 from the piezoelectric element 5 through the contact plate 9 and the core wire 10 firmly fixed on the contact plate, and is recorded by the receiver (not shown in the figure).

在变换器中传播的声干扰被阻尼杯6吸收，阻尼杯是由诸如硬橡胶或有机玻璃等材料制成的。利用阻尼杯6在套筒3中的移动来实现压电元件5与位于压电元件5的自由端的接触盘9的合轴调整，且压紧在圆盘形保护部件4上。通过改变压电元件5对圆盘形保护部件4的压力的方法来调节阻尼的大小，这样就在外壳1的内部降低了信号的混响和信号波形的失真的程度，从而提高了检测的准确度。Acoustic disturbances propagating in the transducer are absorbed by the damping cup 6, which is made of a material such as hard rubber or plexiglass. The movement of the damping cup 6 in the sleeve 3 is used to adjust the axis of the piezoelectric element 5 and the contact plate 9 located at the free end of the piezoelectric element 5 , and press it against the disc-shaped protective member 4 . The damping is adjusted by changing the pressure of the piezoelectric element 5 on the disc-shaped protective part 4, which reduces the reverberation of the signal and the distortion of the signal waveform inside the shell 1, thereby improving the accuracy of detection Spend.

因为套筒3和与其一起安装在其中的圆盘形保护部件4、压电元件5和阻尼杯6都是可拆卸的，所以在其全部装配完毕之前，可以保证对给定的变换器进行调整和校准，也就是说，可以测定振幅频率响应特性和平面内的方向图，以及评价所接收信号的波形。Because the sleeve 3 and the disc-shaped protective part 4, piezoelectric element 5 and damping cup 6 installed therein are all detachable, it is guaranteed that a given transducer can be adjusted before it is fully assembled. And calibration, that is, the amplitude-frequency response characteristics and in-plane pattern can be determined, as well as the waveform of the received signal can be evaluated.

当对产品进行气动试验时，考虑到其结构的工艺特性和几何特性，以及在必须有选择地接收一种类型的波的情况下，应从现有的一系列装配起来的和已校准好的套筒3中选择所需要的套筒，并进行一个一个地调换，将其有效地固定在声发射信号记录用的变换器的外壳1中。When performing pneumatic tests on a product, taking into account the technological and geometrical characteristics of its structure, and in the case where it is necessary to selectively receive one type of wave, it should be selected from an existing series of assembled and calibrated sets. Select the required sleeves from the sleeves 3 and exchange them one by one to effectively fix them in the shell 1 of the transducer for acoustic emission signal recording.

将套筒3作成可拆卸的形式，还能保证提高产品的检测准确度，因为可以避免声发射信号记录用的变换器的附加调谐和校准或中间调谐和校准，以及能保证安装系列很宽的压电元件5。Making the sleeve 3 detachable can also ensure that the detection accuracy of the product is improved, because additional tuning and calibration or intermediate tuning and calibration of the transducer used for acoustic emission signal recording can be avoided, and a wide range of installations can be guaranteed. Piezoelectric element 5.

Claims (2)

Translated fromChinese

1、一种用于声发射信号记录的变换器包括外壳(1)，在该外壳(1)中装有预放大器(7)，该预放大器与圆柱形的压电元件(5)电气连接，该压电元件同轴安装在圆盘形保护部件(4)上，它还包括阻尼元件(6)，其特征是：它附加安装了套筒(3)，该套筒与压电元件(5)同轴安装在外壳(1)的底部(2)上，并且以螺纹连接方式与后者连接，圆盘形保护部件(4)位于套筒(3)的端部，挨着外壳(1)的底部(2)的外表面，而阻尼元件(6)呈杯状，安装在套筒(3)中，以螺纹连接方式与其连接，并且包围着用以实现压电元件(5)与预放大器(7)的电耦合的机构(8)的布置区域内的压电元件。1. A transducer for acoustic emission signal recording comprises a housing (1), in which a pre-amplifier (7) is housed, and the pre-amplifier is electrically connected to a cylindrical piezoelectric element (5), The piezoelectric element is coaxially installed on the disc-shaped protective part (4), and it also includes a damping element (6), which is characterized in that it is additionally equipped with a sleeve (3), which is connected to the piezoelectric element (5 ) is installed coaxially on the bottom (2) of the shell (1) and is connected with the latter in a threaded connection, the disc-shaped protective part (4) is located at the end of the sleeve (3), next to the shell (1) The outer surface of the bottom (2), and the damping element (6) is cup-shaped, installed in the sleeve (3), connected with it by screw connection, and surrounds the piezoelectric element (5) and the pre-amplifier ( 7) The piezoelectric element within the arrangement area of the electrically coupled mechanism (8).2、根据权利要求1所述的变换器，其特征为：用来实现压电元件（5）与预放大器（7）的电耦合的机构（8）包括接触盘（9）和心线（10），该接触盘安装在压电元件（5）的自由端，该心线穿过设于阻尼杯（6）的底部上的孔（11），其一端牢固地连接在接触盘（9）上，而另一端与预放大器（7）电气连接。2. The converter according to claim 1, characterized in that: the mechanism (8) used to realize the electrical coupling of the piezoelectric element (5) and the pre-amplifier (7) includes a contact plate (9) and a core wire (10 ), the contact plate is installed on the free end of the piezoelectric element (5), the core wire passes through the hole (11) on the bottom of the damping cup (6), and one end is firmly connected to the contact plate (9) , while the other end is electrically connected to the pre-amplifier (7).

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