JPH0637303Y2 - Vibration meter - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Industrial Field of the Invention The present invention relates to a vibrometer used for confirming the quality of operation by detecting the vibration associated with the operation of a valve such as a steam trap or the vibration of a rotating shaft.

2. Description of the Related Art Conventionally, as a vibrometer, for example, there is one disclosed in Japanese Utility Model Laid-Open No. 58-187739. This is because the detection needle whose one end is pressed against the object to be detected is fixed to the casing of the probe, and the vibration that propagates through the detection needle is sent to the other end of the detection needle using an ultrasonic microphone that uses a piezoelectric element to make an electrical signal. Is converted to, the electric signal is amplified and the needle of the meter is shaken, and the speaker is sounded.

Problems to be Solved by the Invention In the above, the vibration from the detection needle is detected and the needle of the meter is shaken or the speaker is sounded, so that the vibration level can be detected. However, this method has a problem that a certain pressing force cannot be obtained due to individual differences, and a correct determination cannot be made with the obtained vibration level.

The technical problems of the present invention can be easily handled by anyone,
It is to be able to correctly judge the vibration.

Means for Solving Problems The technical means of the present invention taken to solve the above problems is to mount the detecting needle on the casing of the spreader so as to be slidable in the axial direction, and urge the detecting needle with a spring. And push one end of the detection needle against the object to be detected so that it protrudes from the casing.
The spring is compressed by pressing one end of this detection needle, and in the case where a stopper for restricting the compression amount of the spring is provided, when the spring is compressed to the restriction position by the stopper, the measurement start state is set. It is a switch provided with a switch that is turned off when the compression amount of the spring is less than that.

Action The action of the above technical means is as follows.

When one end of the detection needle is pressed against the object to be detected such as the steam trap valve casing or the bearing part of the rotating shaft, the spring is compressed and one end of the detection needle moves toward the casing, and the switch contacts the stopper. Goes in. The detection needle cannot be pushed further by the stopper. Further, when the pressing force is weakened, the amount of movement of the detection needle in the casing direction also decreases and the switch is turned off. Therefore, it is possible to confirm that the pressing force is not pressed by the stopper with a certain force or more and that the pressing force is reduced by turning off the switch, so that anyone can always detect the accurate vibration level with the constant pressing force. .

Effect of the Invention The present invention has the following unique effects.

Since the vibration is measured only when the detection needle is pressed against the object to be detected with a constant pressing force, the reliability of the measured vibration level is improved.

Example An example showing a specific example of the present invention will be described. (See FIG. 1) The entire vibrometer is composed of a detector 1, an arithmetic unit 50, and a cable 51 connecting them. The detector 1 is formed of a detection needle 2, a detection needle holding member 4, a front cover 6 connecting the detection needle holding member 4 and the main body 5, and a rear cap 7 having a cable outlet 25.

A holding plate for holding the diaphragm mounting member 11 is provided in a substantially cylindrical internal space formed by the front cover 6 and the main body 5.
15, O-ring 17 for holding plate 15 and ultrasonic microphone 16
A spring holder (19), which is connected to a microphone holder (18) that is held via the printed circuit board (20), and a printed circuit board (20) having a circuit for amplifying a detection signal are arranged.

The upper half of the detection needle holding member 4 is conical and the lower half is cylindrical. A vertical hole 9 penetrating therethrough is formed in the central portion, and the detection needle 2 is arranged inside. The detection needle 2 slides in the detection needle holding member 4 until the tip of the detection needle holding member 4 contacts the surface of the object to be detected. The detection needle 2 has a substantially columnar shape, and the temperature sensor 10 is arranged at one end and the other end is press-fitted into the diaphragm mounting member 11. The lead wire from the temperature sensor 10 is provided with a lead wire hole 12 provided halfway in the center of the detection needle 2, a vertical hole 9 of the detection needle holding member 4, a communication hole 14 for connecting the holding plate 15, the spring holder 19, and the microphone holder 18. And the wiring inside the printed circuit board 20.

The diaphragm 21 is screwed onto one end of the diaphragm mounting member 11. An ultrasonic microphone 16 is arranged so as to face the diaphragm 21. The pins of the ultrasonic microphone 16 are connected into the printed circuit board 20. The spring holder 19 has a cylindrical space inside, and has a coil spring 22 for maintaining a constant pressing force of the detection needle 2 against the object to be detected.

A micro switch 31 is attached to the holding plate 15. The lead wire from the micro switch 31 is connected to the printed board 20. The micro switch 31 is switched on when the distance from the diaphragm mounting member 11 is equal to or more than a certain value, and is turned off when the distance is less than a certain value. This distance is the position where the tip of the detection needle 2 is pushed to the tip of the detection needle holding member 4. The holding plate 15, the spring holder 19, and the microphone holder 18 are joined by screws 23.

The arithmetic unit 50 is composed of a functional unit for arithmetically processing each signal sent from the printed circuit board 20 in the detector 1, a display unit and the like.

The entire device operates as follows. When the temperature sensor 10 at the tip of the detector 1 is pressed against the object to be detected, the detection needle 2 is pushed to the tip of the detection needle holding member 4 against the biasing force of the coil spring 22, and the micro switch 31 is pushed at this position. Then, the arithmetic unit 50 enters the measurement start state. In this embodiment, the tip of the detection needle holding member 4 also serves as a stopper. The temperature signal is directly transmitted to the arithmetic unit 50 through the lead wire, and at the same time, mechanical vibration is transmitted to the diaphragm mounting member 11 through the detection needle 2 and vibrates the diaphragm 21. The vibration of the diaphragm 21 propagates through the space inside the microphone holder 18 and is transmitted to the facing ultrasonic microphone 16, and is sent as a vibration signal to the arithmetic unit 50 through the printed circuit board 20.

The arithmetic unit 50 converts the signal from the temperature sensor 10 into a saturated pressure corresponding to the measured temperature. Also, the relationship between the vibration level and the leakage amount according to the pressure of the steam system is stored. The steam leakage amount is calculated and displayed from the pressure and the vibration level.

The detection needle 2 is not pushed further by the detection needle holding member 4, and when the pressing force is weakened, the detection needle 2
Since the amount of pushing in is reduced and the switch is turned off, a decrease in pushing force can be confirmed, so that anyone can always detect an accurate vibration level with a constant pushing force.

[Brief description of drawings]

 FIG. 1 is a block diagram of the present invention and a sectional view of a detector. 1: Detector, 2: Detection needle 4: Detection needle holding member, 10: Temperature sensor 16: Ultrasonic microphone 18: Microphone holder, 20: Printed circuit board 21: Vibration plate, 22: Coil spring 31: Micro switch 50: Calculation Device, 51: cable

Claims (1)

[Scope of utility model registration request] 1. A detection needle is slidably attached to a casing of a loader, and a spring biases the detection needle to press one end of the detection needle against an object to be detected so as to project from the casing. The switch is designed to compress the spring by pressing one end, and in the case where a stopper for restricting the compression amount of the spring is provided, when the spring is compressed to the restriction position by the stopper, it is a switch to start the measurement. A vibrometer with a switch that turns off when the amount of spring compression falls below that level.