JP4582959B2 - Method and apparatus for removing fluorescence in fluorescence inspection - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for removing unnecessary fluorescent components adhering to the surface of a workpiece during a fluorescence inspection, and an apparatus for carrying out the method.
[0002]
[Prior art]
The fluorescence inspection is one of the most common methods for detecting defects on the surface of a workpiece. In the fluorescence inspection, (1) the workpiece is immersed in a fluorescent solution in which the fluorescent component is dispersed, so that the fluorescent component penetrates into the defect (penetration treatment), and (2) the unnecessary fluorescent component adhering to the workpiece surface is then removed. Generally, it is performed by a procedure of removing (cleaning / removing process), and (3) irradiating the workpiece with black light and then detecting defects visually.
[0003]
As a method for cleaning / removing the fluorescent component, a method of cleaning by spraying high-pressure water onto the surface of the workpiece (for example, see JP-A-7-270341), a method of placing the workpiece in a predetermined container, and washing or dusting the workpiece. The so-called “rice togi” method is used.
[0004]
[Problems to be solved by the invention]
However, since the above-described conventional method has a poor fluorescence removal efficiency, it takes a long cleaning time and requires a large amount of cleaning water. For this reason, the cost of a cleaning operation becomes very high. In addition, the fluorescent component may not be completely removed even with such costly cleaning. When the black light irradiation inspection is performed after the work in which the fluorescent component remains is dried as it is, a thin fluorescent color is emitted even on the work surface other than the defective portion, so that it becomes very difficult to detect a fine defect. The disadvantages listed above are particularly problematic when it is necessary to inspect a large amount of workpieces in the mass production process.
[0005]
The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a method capable of quickly and surely removing the fluorescent component on the workpiece surface, and an apparatus for executing the method.
[0006]
[Means for Solving the Problems]
In order to achieve the above object, the present invention provides a method for removing unnecessary fluorescent components adhering to the surface of a workpiece that has been subjected to a fluorescent component penetrating treatment in a fluorescent flaw detection test, in a cleaning liquid containing a plurality of workpieces in a container. The workpieces are caused to collide with each other by dipping and stirring the cleaning liquid in the container, thereby removing the fluorescent component adhering to the workpiece surface.
[0007]
The cleaning liquid can be stirred with a screw immersed in the cleaning liquid. In this case, a substantially cylindrical container is used as the container, and a screw having a blade spirally formed around a shaft portion is used as the screw, and the screw is inserted into a substantially central portion of the container. By rotating, from the upper part of the container to the lower part in the vicinity of the screw, then toward the peripheral part of the container, then from the lower part of the container to the upper part at the peripheral part of the container, and then toward the central part of the container, and thereafter In the vicinity of the screw, it is preferable to form a circulation flow of the cleaning liquid from the upper part of the container toward the lower part.
[0008]
The method of the present invention is particularly advantageous when a large amount of a substantially spherical workpiece is handled.
[0009]
In addition, although a washing | cleaning liquid can be changed suitably according to the kind of fluorescent solution, generally water (it does not matter even if it is a tap water) is used.
[0010]
Furthermore, the present invention provides a substantially cylindrical container for containing a cleaning liquid and a work, and a screw that is inserted into the container and forms the flow of the cleaning liquid in the container in order to carry out the above method. A fluorescent component removing apparatus, wherein the workpieces collide with each other by stirring the cleaning liquid in the container with the screw, thereby removing the fluorescent component adhering to the surface of the workpiece. .
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the drawings. 1 to 3 are diagrams for explaining an embodiment of the present invention.
[0012]
First, the fluorescence removing device will be described with reference to FIG.
[0013]
In FIG. 1, the code | symbol 1 is the base of a fluorescence component removal apparatus. The upper surface of the base 1 serves as a placement surface 3 on which the cleaning container 2 is placed. A support column 4 is provided on the back surface of the base 1. A rotary drive device 7 using a built-in electric motor 6 as a power source is attached to the support column 4 via a slider 5 so as to be movable in the vertical direction. A stirring screw 9 is detachably attached to the main shaft 8 of the rotation drive device 7. A rotation speed adjuster 10 for adjusting the rotation speed of the main shaft 8 of the rotation driving device 7 and a timer 11 for setting the operation time of the rotation driving device 7 are attached to the support 4. The rotation speed adjuster 10 may adjust the rotation speed by changing the supply voltage to the electric motor 6 such as a slidac, and the supply frequency to the electric motor 6 such as an inverter power supply may be adjusted. The rotational speed may be adjusted by changing it.
[0014]
Next, a fluorescence removal method using the fluorescence removal apparatus shown in FIG. 1 will be described with reference to FIG. 1 and FIG.
[0015]
First, a plurality of workpieces W that have been subjected to the fluorescence permeation treatment and an appropriate amount of cleaning liquid L are placed in a dedicated container 2. As the container 2, a cylindrical container is preferably used. The cleaning liquid L to be used varies depending on the type of the fluorescent liquid, but when the water-washable fluorescent liquid is used as the fluorescent liquid, the cleaning liquid L may be ordinary water such as tap water. It is preferable that the work W is sufficiently drained of the fluorescent solution before being put into the container 2.
[0016]
Next, the container 2 is set at a predetermined position on the placement surface 3. Next, as shown in FIGS. 2 (a) and 2 (b), the screw 9 is lowered while rotating at a low speed and inserted into the container 2. As shown in FIG. It is assumed that the distance s is slightly separated from the bottom.
[0017]
Next, the screw 9 is rotated at high speed, and the cleaning liquid L in the container 2 is continuously stirred for a predetermined time. As shown in FIG. 2 (c), the workpiece W accommodated in the container 2 along with the agitation moves on the flow of the cleaning liquid formed in the container 2 and moves in the container 2. The workpieces W collide with each other while moving in the container 2, whereby the fluorescent component adhering to the surface of the workpiece W is scraped off. That is, the so-called “friend rubbing” physically removes and removes the fluorescent component adhering to the surface of the workpiece W. It is preferable that the duration of the high speed rotation is set by the timer 11. Moreover, it is preferable to perform high speed rotation at a constant speed.
[0018]
When the predetermined time has elapsed, the screw 9 is again rotated at a low speed, and in this state, the screw 9 is pulled up from the container 2 as shown in FIG. Through the series of operations described above, the fluorescent component adhering to the surface of the workpiece W can be removed easily, in a short time, and reliably.
[0019]
The flow of the liquid formed in the container 2 flows from the upper part of the container 2 toward the lower part in the vicinity of the screw 9, and then toward the peripheral part of the container 2, and then to the peripheral part of the container 2, as shown by arrows in FIG. From the viewpoint of improving the cleaning efficiency, it is preferable that the circulation flow is directed from the lower part of the container 2 to the upper part, and then to the central part of the container 2, and then again from the upper part of the container 2 to the lower part in the vicinity of the screw 9. is there. As shown in FIG. 3, it is preferable to use a screw 9 having a shaft portion 9a and a blade 9b formed in a spiral shape around the shaft portion 9a as the screw 9 for forming such a circulating flow. is there.
[0020]
The cleaning conditions such as the number of rotations of the screw 9 and the cleaning time need to be set as appropriate according to the size and quantity of the workpiece W. Further, the ratio between the number of workpieces W and the amount of the cleaning liquid L needs to be set as appropriate according to the type of workpieces W. In particular, it is necessary to pay attention to the fact that the removal effect due to “rubbing” cannot be sufficiently obtained when there are too few workpieces W put into the container 2 at one time. In addition, when the quantity of the workpiece | work W accommodated in a container is many with respect to an appropriate number, or when the drainage of the workpiece | work W before washing | cleaning is inadequate etc., a fluorescence content to a desired state is carried out. In such a case, the above process may be performed a plurality of times.
[0021]
As an example, when cleaning a ceramic bearing ball having a diameter of about several millimeters (here, a diameter of 2.4 mm) used for a micro ball bearing, the rotational speed of the low-speed rotation is 70 to 100 rpm and the rotational speed of the high-speed rotation. May be set to 1550 to 1650 rpm, and the rotation duration of high-speed rotation may be set to 1 to 2 minutes. According to this processing condition, it has been confirmed that the fluorescent component can be removed to the extent that there is no hindrance to observation with black light.
[0022]
The present invention is not limited to the above embodiment. That is, if the operation based on the present invention of removing the fluorescent component by agitating the cleaning solution and causing the workpieces in the cleaning solution to collide with each other can be achieved, the apparatus for realizing this operation has no configuration. Is not limited.
[0023]
【The invention's effect】
As described above, according to the present invention, the fluorescent component on the workpiece surface can be removed quickly and reliably.
[Brief description of the drawings]
FIG. 1 is a diagram schematically showing a configuration of a fluorescence removing device.
FIG. 2 is a diagram illustrating a cleaning process.
FIG. 3 is a view for explaining a liquid circulation mode in a suitable container and a screw suitable for it.
[Explanation of symbols]
W Work L Cleaning liquid 2 Container 9 Screw

Claims (5)

In the method of removing unnecessary fluorescent component adhering to the workpiece surface that has been subjected to the fluorescent component penetration treatment in the fluorescent flaw detection,
A plurality of workpieces are immersed in a cleaning liquid contained in a container, and the cleaning liquid in the container is stirred to cause the workpieces to collide with each other, thereby removing a fluorescent component attached to the surface of the workpiece. , How to remove fluorescence. The method for removing a fluorescent content according to claim 1, wherein the cleaning liquid is stirred by a screw immersed in the cleaning liquid. A substantially cylindrical container is used as the container, and a screw having a blade spirally formed around a shaft portion is used as the screw, and the screw is inserted in a substantially central portion of the container,
By rotating the screw, it goes from the upper part of the container to the lower part in the vicinity of the screw, then goes to the peripheral part of the container, then goes from the lower part of the container to the upper part at the peripheral part of the container, and then to the central part of the container. 3. The method for removing a fluorescent content according to claim 2, wherein a circulation flow of the cleaning liquid is formed in a direction from the top to the bottom in the vicinity of the screw. The method for removing a fluorescent content according to any one of claims 1 to 3, wherein the workpiece is substantially spherical. A substantially cylindrical container for containing the cleaning liquid and the workpiece;
A screw inserted into the container and forming a flow of the cleaning liquid in the container,
The fluorescent component removing apparatus, wherein the workpieces collide with each other by stirring the cleaning liquid in the container with the screw, thereby removing the fluorescent component adhering to the surface of the workpiece.

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