JP4397323B2 - Magnetic powder flaw detector - Google Patents

Description

    The present invention relates to a magnetic material surface by a fluorescent magnetic powder pattern in which a magnetic powder coated with a fluorescent substance or a magnetic powder solution in which such a magnetic powder is mixed is dispersed and magnetized on the surface of the magnetic material, and light is emitted by ultraviolet irradiation. The present invention relates to a magnetic powder type flaw detection apparatus for flaw detection.

The principle of this type of magnetic particle type flaw detection apparatus is well known as disclosed in Patent Document 1, Patent Document 2, and the like, and an apparatus automated by Patent Document 3 is also well known. On the other hand, the inspector moves the magnetizer along the surface of the steel material or the like to which the magnetic powder or magnetic powder solution has been dispersed, and the inspection area is irradiated with ultraviolet light by an ultraviolet light source held in hand, and the fluorescent magnetic powder is generated due to the generation of magnetic poles caused by scratches. A flaw detection by a manual operation of observing a pattern and imaging with a camera as necessary is also performed.
JP-A-11-160283 JP-A-5-322854 Japanese Patent Laid-Open No. 10-282063

  However, in the case of such a manual type, the magnetizer is lifted and moved along the surface of the magnetic material in the inspection region, and the separate ultraviolet light source is also moved by hand, and further magnetically permeable to the magnetic material. It is also necessary to operate the lowering detection switch each time, so that there is a problem that work or power efficiency is poor and a physical burden is large in the case of long-time inspection.

  In view of the above, an object of the present invention is to provide a manually operated magnetic particle type flaw detection apparatus capable of reducing physical burden and improving work efficiency under power saving.

  In order to achieve this object, the present invention provides a magnetic powder type flaw detection method in which the surface of a magnetic material is flawed by a fluorescent magnetic powder pattern in which fluorescent magnetic powder dispersed and magnetized on the surface of the magnetic material is emitted by ultraviolet irradiation. In the apparatus, the tip of the core leg on both sides is formed as a pair of magnetic pole heads on the lift base supported by a base with a wheel running on the surface of the magnetic material so that it can be pushed down via a return spring. In addition, a core around which the exciting coil is wound and an ultraviolet light source that irradiates ultraviolet rays in response to the operation of the ultraviolet irradiation switch are attached to the surface of the magnetic material in the region between the magnetic pole heads. In addition, a magnetizing switch means is provided at a position above the wheel, and at the base of the carriage, detecting that the elevating carriage is lowered and automatically supplying power to the excitation coil. When the push-down operation is performed against the return spring, the magnetization switch means is turned on, and the magnetic head is brought into contact with the surface of the magnetic material, and when the push-down operation is released, the lifting cart is lifted by the bias of the return spring. Thus, the magnetization switch means is turned off, and the magnetic pole head is levitated from the surface of the magnetic material.

  In order to make it unnecessary to carry the camera, the camera for imaging the fluorescent magnetic powder pattern is attached to the lift cart so as to be positioned between the magnetic pole heads. In order to link the magnetization and the ultraviolet irradiation, according to claim 3, the magnetization switch means also functions as an ultraviolet irradiation switch. According to a fourth aspect of the present invention, there is provided a round-pipe-like leg portion that is provided on both sides of the elevating type carriage, two casters are provided on both sides, and each side is provided with a return spring. Is engaged with the peripheral surface of the cylindrical carriage base portion so as to be slidable up and down, and a magnetizing switch means is formed between the inside of the carriage base portion and the lower end portion of the round pipe-like leg portion.

  According to the first aspect of the present invention, since the magnetizer and the ultraviolet light source can be integrated and moved while the magnetic pole head is floated by the wheels, the magnetic head can be moved quickly, the physical burden is greatly reduced, and the inspection can be performed quickly. it can. The magnetizer is automatically activated during the push-down process of the elevating carriage, so that magnetization is performed only at the time of inspection, and the power supply operation of the ultraviolet light source is facilitated, thereby saving power. .

  According to the invention of claim 2, the operability is further improved by integrating the camera for imaging the fluorescent magnetic powder pattern. According to the third aspect of the present invention, since the driving of the ultraviolet light source is linked with the magnetization in combination with the magnetization switch means, further power saving can be achieved and the operability is improved. According to invention of Claim 4, it is comprised by the structure where a raising / lowering cart is not bulky, and it becomes possible to move to arbitrary directions easily.

  A manually operated magnetic powder type flaw detection apparatus according to an embodiment of the present invention will be described with reference to FIGS. This device includes a liftable carriage 10 having legs 11 on both sides, a substantially U-shaped core 20, a plate-like ultraviolet light source 25 in which ultraviolet (UV) LED groups are arranged in a plane on a substrate 25 a, and An imaging camera 27 such as a CCD camera for outputting a video signal is integrated. As shown in FIG. 2, the round pipe-like leg portions 11 on both sides are respectively provided with two casters 13 and cylindrical carriage base portions 12 on both sides in which return springs 16 that are, for example, coil springs are accommodated. It is slidably engaged with the inner peripheral surface of the lens and supported so as to slide up and down.

  The upper side portion of the core 20 is attached in a state where it is engaged with the upper surface and both side portions of the carriage main body 14 and the bottom surface portion 14a that is partially formed on both sides and under which the leg portion 11 is provided. An exciting coil 21 is wound around the core leg portions 20a on both sides, and the tip portions thereof are formed as magnetic pole heads 23 that are inclined in directions approaching each other to constitute a magnetizer. The core 20 is set to be shorter in height than the elevating carriage 10, and the height position of the magnetic pole head 23 is set to a position above the casters 13 in a normal state so as to float from the magnetic material surface 1 which is a running surface. Has been.

  Between the leg portions 11 on both sides and the core leg portions 20a on both sides, the substrate 25a of the ultraviolet light source 25 is attached obliquely so as to irradiate the magnetic material surface 1 in the region between the magnetic pole heads 23 with ultraviolet rays. Is detachable from the substrate 25a. The imaging camera 27 is attached to a support plate 27a protruding from the middle part of the carriage main body 14 so as to image the magnetic material surface 1 between the magnetic pole heads 23 from above.

  As shown in FIG. 2, a contact 17a is attached to the lower end surface of the leg 11 placed on the return spring 16, and a counterpart contact 17c is attached to the inner bottom surface of the carriage base 12 via a spring 17b. In addition, a lowering detection switch 17 for magnetization for supplying the commercial power to the exciting coil 21 by detecting that the leg portion 11, that is, the elevating carriage 10 is lowered from the normal height position to a predetermined position is configured. That is, this switch has a position sensor function and constitutes a magnetization switch means. As a result, when the lifting carriage 10 is pushed against the return spring 16 from above to bring the magnetic pole head 23 into contact with the magnetic material surface 1 to be inspected, the lowering detection switch 17 is turned on halfway. A DC power source for driving the ultraviolet light source 25 is accommodated in the cart body 14, and commercial power is supplied to the ultraviolet light source 25 by turning on the ultraviolet irradiation switch 19. Further, an AC power cable 18 that feeds power to the DC power source of the exciting coil 21 and the ultraviolet light source 25 and a video cable 18 a of the imaging camera 27 are led out from the cart body 14.

  The operation of the magnetic particle type flaw detector thus configured is as follows. During flaw detection, a magnetic powder solution is sprayed on the magnetic material surface 1 to be inspected. In some cases, dry magnetic powder that is not mixed in the solution is sprayed. Next, when the elevating carriage 10 is placed on the magnetic material surface 1, for example, the surface of a steel material, is moved by pushing it manually, and the carriage main body 14 is pushed down against the return spring 16 from above in the spraying region to be inspected. The magnetic pole head 23 descends and comes into contact with the magnetic material surface 1, and the lowering detection switch 17 is turned on during the lowering, and an AC current is supplied to the exciting coil 21. As a result, when a magnetic field is generated on the magnetic material surface 1 between the two magnetic pole heads 23 and a crack such as a crack is present between the magnetic heads, magnetic poles are generated according to the shape of the magnetic material, and the distribution density of the magnetic powder changes, resulting in a pattern. It is formed. When the ultraviolet irradiation switch 19 is turned on, a fluorescent magnetic powder pattern emitted by ultraviolet rays is observed.

  When the magnetization is stopped, when the push-down operation of the lift cart 10 is released, the leg 11 is raised and returned to the original position by the urging of the return spring 16, and the magnetic pole head 23 is levitated and interlocked. When the lowering detection switch 17 is turned off, the magnetization is stopped. In the push-down operation of the lift cart 10 or its release state, if necessary, an image can be taken from above by the imaging camera 27 and the image can be monitored or stored on the screen of the image display device at another location.

  In the above-described embodiment, the power supply of the ultraviolet power source is performed independently of the magnetization. However, the drop detection switch 17 also functions as an ultraviolet irradiation switch, and the power supply of the direct current power source of the ultraviolet light source is linked. By turning on and off, the ultraviolet irradiation switch 19 can be eliminated. The ultraviolet light source may be an ultraviolet lamp instead of a UV LED. The excitation coil 21 can be driven not by a commercial power supply but by a DC power supply for the excitation coil 21 housed in the cart body 14 via the lowering detection switch 17. As the wheel, a caster is used so as to be able to travel in an arbitrary direction, but in some cases, a normal unidirectional wheel may be used. In addition, the wheels can be two-wheeled on both sides instead of four-wheeled, and the storage posture can be supported by the magnetic pole head so that the core can be moved while being inspected. In addition, various modifications can be made within the scope of the present invention as the structure of the lift cart.

  The magnetizing switch means is not limited to the two-contact type that contacts and separates in the opposed state, but is configured by using a sliding contact, or a photoelectric sensor that detects the lowering to a predetermined position and a switch that responds to the position sensor. Can also be used. Furthermore, instead of detecting the lowering position on the way, it detects the descent start or descent end from the normal height position of the elevating carriage, or detects the downward pressing force against the elevating carriage to react the switch It is also possible to configure it.

1 is a perspective view of a magnetic particle flaw detector according to an embodiment of the present invention. It is sectional drawing of the leg part lower end part of the same apparatus. It is sectional drawing of the intermediate part of the apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Magnetic material surface 10 Lifting cart 11 Leg 12 Cart base 13 Caster 16 Return spring 17 Lowering detection switch 19 UV irradiation switch 20 Core 20a Core leg 21 Excitation coil 23 Magnetic pole head 25 Ultraviolet light source 27 Imaging camera

Claims (4)

In a magnetic particle type flaw detection apparatus that flaws the surface of a magnetic material with a fluorescent magnetic powder pattern in which the fluorescent magnetic powder dispersed and magnetized on the surface of the magnetic material is emitted by ultraviolet irradiation,
The tip of the core leg on both sides is formed as a pair of magnetic pole heads on an elevating carriage supported by a carriage base with wheels running on the surface of a magnetic material so as to be able to be pushed down via a return spring, and an exciting coil And an ultraviolet light source that irradiates ultraviolet light in response to an operation of an ultraviolet irradiation switch on the surface of the magnetic material in the region between the magnetic pole heads and a height position of the magnetic pole head, Magnetizing switch means is provided that is set at a position above the wheel and that detects that the elevating carriage is lowered and automatically drives the excitation coil at the carriage base,
When the elevating carriage is pushed down against the return spring, the magnetization switch means is turned on, and the magnetic pole head comes into contact with the magnetic material surface,
When the push-down operation is released, the lifting cart is raised by the biasing of the return spring to turn off the magnetization switch means, and the magnetic pole head floats from the surface of the magnetic material. Magnetic powder type flaw detector.   2. The magnetic particle type flaw detection apparatus according to claim 1, wherein a camera for imaging the fluorescent magnetic powder pattern is attached to the lift carriage so as to be positioned above the magnetic pole head.   3. A magnetic particle type flaw detection apparatus according to claim 1, wherein the magnetization switch means also functions as an ultraviolet irradiation switch. The round pipe-shaped legs, which are installed on both sides of the elevating carriage, are slidable on the peripheral surfaces of the cylindrical carriage bases on both sides where two casters are installed and each return spring is stored. Together
The magnetic powder type flaw detection apparatus according to any one of claims 1 to 3, wherein a magnetizing switch means is formed between the inside of the carriage base and the lower end of the round pipe-like leg.

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