JPH0220687Y2 - - Google Patents

Description

[Detailed Description of the Invention] Technical Field The present invention relates to a measurement head of an ultrasonic flaw detector that performs flaw detection by bringing a probe into close contact with the end face of an axle of a railway vehicle or the like.

Conventional technology A probe is applied to the end face of an object to be inspected to generate an ultrasonic pulse, the probe detects waves corresponding to the ultrasonic pulse, and these are displayed on a cathode ray tube (CRT). Ultrasonic flaw detectors for detecting flaws are already known. By the way, when performing flaw detection, if the probe rises even slightly from the surface of the object to be inspected, energy loss becomes extremely large and measurement becomes difficult. For this reason, conventionally, measurements were taken while pressing the probe against the object to be inspected by hand. However, in hand-held measurements, the pressing force of the probe against the object to be inspected differs each time the measurement is performed, leaving doubts about the reliability of the measurement results. Such a problem occurs particularly in the case of an object to be inspected, such as an axle of a railway vehicle, in which only a small end face is exposed to the outside. That is, in the case of the axle of a railway vehicle, it is difficult to apply the probe to the end face of the axle with a constant pressing force due to spatial constraints, making it difficult to obtain accurate measurement results. Further, when performing flaw detection while moving the probe continuously or intermittently on the end face of the axle, it has been difficult to keep the contact pressure of the probe constant.

Purpose of the invention Therefore, the purpose of the present invention is to provide a measurement head for an ultrasonic flaw detector that can easily bring a probe into contact with an axle and keep the contact pressure substantially constant.

Structure of the Invention To achieve the above object, the present invention will be explained with reference to the reference numerals in the drawings showing the embodiments for ease of understanding. an elastic body 8 disposed so as to press the probe 7 toward the end surface 1a of the axle 1; A holder 9 having a portion 13 that holds the elastic body 8 in a pressing manner and a portion 14 that faces the outer peripheral surface of the axle 1 or the member 2 surrounding the axle; and the opposing portion 14 of the holder 9. an engaging body 10 that is supported by and removably engages with the side surface of the axle 1 or the side surface of the member 2 surrounding the axle 1 with elasticity; a ball 10a that is supported so as to be displaceable and has a portion protruding so as to engage with the side surface of the axle 1 or the side surface of the member 2 surrounding the axle 1; The present invention relates to a measuring head of an ultrasonic flaw detector for an axle, which is characterized by an elastic protrusion comprising a spring 10b that provides a biasing force.

Effects of the Invention According to the present invention, the axial position of the probe 7 is determined by the engagement between the engaging body 10 and the axle 1 or the member 2 surrounding the axle 1. Therefore, it becomes possible to perform ultrasonic flaw detection while keeping the contact pressure of the probe 7 against the axle 1 substantially constant, and it becomes possible to perform highly reliable flaw detection. In addition, the ball 1 of the engaging body 10
0a has elasticity and can be detachably attached to axle 1 or axle 1.
Since it engages with the member 2 surrounding the measuring head, it is easy to attach and detach the measuring head. In addition, since the probe 7 is in elastic contact with the axle 1 and the engaging body 10 is only in elastic engagement with the axle 1 or the member 2 surrounding it, the end face 1a of the axle 1 It is possible to easily change the position of the probe.

Embodiment Next, an ultrasonic flaw detector according to an embodiment of the present invention will be described with reference to FIGS. 1 and 2. In Figure 1, 1 is the axle of a railway vehicle as the object to be inspected, 2
is a bearing member surrounding this axle 1, 3 is a measuring head,
4 is the main body of the flaw detector. To explain these in more detail, the cylindrical bearing member 2 surrounding the axle 1 so that the end surface 1a of the axle 1 is exposed has a ring-shaped engagement groove 5 on its outer peripheral surface, and an inclined surface 6 at the end. has. The engagement groove 5 is a groove for attaching the cap when the vehicle is used.

The measurement head 3 includes a probe 7, an elastic body 8 made of a coil spring that presses the probe 7 in the direction of the axle 1, a cup-shaped or cap-shaped holder 9 that holds the probe 7 and the elastic body 8, and a bearing. and an engaging body 10 that engages with the groove 5 of the member 2. The probe 7 is a type that can transmit and receive waves, so it has a built-in transmitter that applies ultrasonic waves from the axle 1 and a receiver that receives reflected waves from inside the axle 1. 4 is combined.

The flaw detector body 4 includes a transmitting circuit that generates electric pulses, a receiving circuit that amplifies and detects the electrical signal obtained from the probe 7, an oscilloscope that displays the received wave in waveform, and a transmitting circuit that synchronizes and drives the oscilloscope. Contains synchronous circuits etc.

The holding body 9 has a first tip-shaped portion 9a with a small diameter.
and a second pot-shaped portion 9b having a large diameter.
A probe holding portion 12 constituted by a cylindrical portion of
It also has an elastic body holding part 13 formed by the bottom of the first socket-shaped part 9a, and a bearing facing part 14 formed by the cylindrical part of the second socket-shaped part 9b. has. Since the inner diameter of the probe holding portion 12 is approximately equal to the outer diameter of the probe 7,
The probe 7 is kept at a substantially constant position relative to the holder 9. However, since the probe 7 is inserted into the holding portion 12 with some clearance, the axle 1
can be displaced in the axial direction.

The elastic body 8 is made of a coil spring, and is disposed between the back surface of the probe 7 and the elastic body holding portion 13, and applies a biasing force to the probe 7 in the direction of pressing the probe 7 against the axle 1.
is granted to.

The elastic engagement bodies 10 are provided at four locations inside the cylindrical bearing facing portion 14, and each is configured in the shape of an elastic protrusion or an elastic claw consisting of a ball 10a and a coil spring 10b that presses the ball 10a. The ball 10a and the coil spring 10b are installed in the groove 15 so as not to come off, and a portion of the ball 10a protrudes from the groove 15 and engages with the groove 5 of the bearing member 2.

When the measuring head 3 configured as described above is attached to the axle 1 and the bearing member 2, the probe 7 is applied to the axle end face 1a, and the holder 9 is moved against the bias of the elastic body 8 as shown in FIG. Press to the left with . Since the axle 1 and the bearing member 2 have a large weight, they are considered fixed against the pressure of the measuring head 3 and the biasing force of the elastic body 8, and will not be displaced by the mounting of the measuring head 3. When the holder 9 is pressed leftward in FIG. 1, the balls 10a, which act as elastic protrusions or claws, are pressed by the inclined surface 6 of the bearing member 2 and are displaced in a direction away from the bearing member 2. However, when the ball 10a reaches the engagement groove 5, it is pushed out by the force of the coil spring 10b, and a part of the ball 10a is inserted into the groove 5 to be in an engaged state and positioned there. As a result,
The distance between the back surface 7a of the probe 7 and the elastic body holding portion 13 is kept constant, the force with which the probe 7 is pressed against the axle 1 by the elastic body 8 is also kept constant, and the contact pressure between the two is constant. is maintained. Therefore, highly reliable flaw detection can be performed.

In this embodiment, the bearing member 2 is provided with a ring-shaped engagement groove 5, and the ball 10a and the probe 7 are in elastic contact with each other, so that the measuring head 3 is moved as shown by the arrow in FIG. It can rotate. Therefore, it is extremely easy to perform flaw detection while rotating the probe 7 continuously or intermittently on the axle end face 1a, and the contact pressure can be kept almost constant at various angular positions of the probe 7. It can be kept constant. Therefore, highly accurate flaw detection can be performed.

When removing the measuring head 3, the holder 9 is pulled to the right in FIG. As a result, the ball 10a is displaced in a direction away from the bearing member 2 and comes out of the engagement groove 5.

As is clear from the above, the measuring head 3 of this embodiment has the following advantages.

(a) Since the contact pressure of the probe 7 can be kept constant, highly reliable flaw detection can be performed.

(b) Since the engaging body 10 is an elastic protrusion consisting of a ball 10a and a coil spring 10b, the measuring head 3 can be easily attached and detached.

(c) Since the engagement groove 5 is formed in a ring shape and the ball 10a is elastically engaged therein, it is possible to rotate the measurement head 3 and perform the search at each rotation position. The contact pressure of the feeler 7 can be kept almost constant.

Modifications The present invention is not limited to the above-described embodiments, but includes the following modifications, for example.

(1) Instead of forming the holder 9 in a cup or cap shape, the holders 12, 13 and the opposing portion 14 may be connected to each other by a linear connecting member, and the entire structure may be frame-shaped.

(2) When the axle 1 protrudes beyond the bearing member 2, the engaging body 10 may be directly engaged therewith.

(3) It is also applicable to probes 7 that include only a transmitter or only a receiver.

(4) A spacer may be placed between the probe 7 and the axle 1.

(5) In order to stabilize the engagement of the ball 10a with the groove 5, the groove 5 may have a semicircular cross-sectional shape.

(6) The engagement groove 5 of the bearing member 2 may be omitted and the ball 10a may be strongly engaged with the cylindrical surface by the spring 10b.

In this case, it is desirable to provide the axle 1 or the bearing member 2 with a step that limits the axial position of the measuring head 3. Further, the force of the spring 10b must be set so as to maintain engagement of the ball 10a against the biasing force of the elastic body 8.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a measuring head for an axle according to an embodiment of the present invention, and FIG. 2 is a right side view of the measuring head of FIG. 1. DESCRIPTION OF SYMBOLS 1...Axle, 1a...End face, 2...Bearing member surrounding the axle, 3...Measuring head, 5...Engagement groove, 7
...Probe, 8...Elastic body, 9...Holding body, 10
...Engaging body, 10a...Ball, 10b...Coil spring, 12...Probe holding part, 13...Elastic body holding part, 14...Bearing opposing part, 15...Groove.

Claims (1)

[Claims for Utility Model Registration] A probe 7 that is brought into close contact with the end surface 1a of the axle 1 as an object to be inspected; and an elastic member that is arranged to press the probe 7 toward the end surface 1a of the axle 1. a body 8, a portion 13 that holds the elastic body 8 so that the elastic body 8 presses the probe 7 in the direction of the axle 1, and an outer peripheral side surface of the axle 1 or a member 2 surrounding the axle. a holder 9 having a portion 14 facing the holder 9; a holder 9 supported by the opposing portion 14 of the holder 9 and elastically attachable to and detachable from the side surface of the axle 1 or the side surface of a member 2 surrounding the axle 1; an engaging body 10 that engages with the holding body 9;
a ball 10a which is supported so as to be displaceable and has a portion protruding so as to engage with the side surface of the axle 1 or the side surface of the member 2 surrounding the axle 1; and the ball 10a.
a spring 1 which applies a biasing force in the radial direction of the axle 1 to
1. A measurement head for an ultrasonic flaw detector, characterized in that it is an elastically displaceable protrusion consisting of: