JPS6342737B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus for visually inspecting an object to be inspected in the form of a rotating body, such as a cylinder or cylinder, such as fuel pellets for a nuclear reactor.

For example, nuclear fuel pellets for light water-cooled nuclear reactors are produced by molding low-enrichment round dioxide powder in a mold to form cylindrical green pellets (also called green compacts), which are then heated to high temperatures. The sintered pellets are sintered to make dense sintered pellets, and the outer diameter of the sintered pellets is polished to improve dimensional accuracy, which is used as nuclear fuel pellets by filling them into fuel cladding tubes. These nuclear fuel pellets have an outer diameter of 9 mm to 13 mm.
It is a cylindrical body with a length of 5 mm to 15 mm.

If these nuclear fuel pellets have defects such as cracks or chips on their outer surface, the gap between the pellet surface and the cladding tube will be larger in the defective area than in other areas, resulting in poorer heat transfer than in other areas, and the temperature at the center of the pellet will decrease. Uncertainty increases. Further, there is a difference in the power distribution between parts with many cracks, chips, etc. and parts without, which may adversely affect the reactor performance, or the reactor power may not be able to reach its maximum level.
For this reason, the quality of nuclear fuel pellets is guaranteed by visually inspecting all nuclear fuel pellets before use. Conventionally, this visual inspection method has been as follows: (1) Nuclear fuel pellets are placed on a tray and transported onto an inspection table, and the nuclear fuel pellets are picked up one by one with tweezers and visually inspected (batch inspection). (2) Nuclear fuel pellets are placed directly or via a tray on a conveyor in an upright or lying position, and while being moved, the nuclear fuel pellets are picked up one by one with tweezers, etc., and visually inspected for the appearance of all the pellets. (3) A number of grooves with arcuate bottoms are provided on the bottom of the tray, nuclear fuel pellets are arranged in a lying position in the grooves, vibration is applied to the tray using a vibrator, and the vibration rotates the nuclear fuel pellets. A method is used in which the outer circumferential surface of the nuclear fuel pellets is visually inspected while the pellets are being moved, and if necessary, the nuclear fuel pellets are picked up one by one with tweezers and the end surfaces are inspected.

However, in this conventional visual inspection method, from the standpoint of protecting the hands from local radiation exposure, one is forced to wear radiation-shielding gloves that significantly impair work efficiency, and in (1) above, the inspection process is time-consuming. It is extremely inefficient, difficult to inspect, and a heavy burden on workers. In the case of (2) above, although the inspection speed is slightly improved, it is not sufficient, and inspection is still difficult, and the burden on the operator is still large. In (3) above, the inspection speed is further improved, but the equipment is insufficient, such as the nuclear fuel pellets on the tray not being rotated evenly with only vibration by the vibrator, and the operator's eyes and hands are fatigued greatly. However, there were drawbacks such as the inability to avoid inspection errors such as uneven inspection.

This invention was made in view of the above circumstances,
By transferring a rotary body-shaped object to be inspected placed on a tray provided on one side of the rollers onto a plurality of rotating rollers rotating in the same direction above the base using a transfer mechanism. A mask mechanism that can reliably rotate a large number of objects to be inspected on the roller simultaneously in a predetermined direction at a predetermined speed, limit a field of view, block a part other than the field of view, and move this field of view. It is possible to reduce eye fatigue and local radiation exposure of the hands of workers, and it is also easier to inspect, increasing inspection speed and increasing work efficiency, thereby reducing the burden on workers. It is an object of the present invention to provide an apparatus for inspecting the appearance of an object to be inspected, which is capable of inspecting objects and is free from inspection errors such as inspection unevenness.

Hereinafter, one embodiment of the present invention will be described based on the drawings. Reference numeral 1 in FIG. 1 is a base, and a food box 2 and a substrate 3 located inside the food box are provided on the top of the base 1, respectively.
A gearbox 4 is located on the left side of the board 3 in FIG.
and a pellet transfer table 6 having a flange portion 5 are attached in a spaced-apart and opposing state. A large number of rollers 7 are arranged in the same direction at predetermined intervals between the gear box 4 and the pellet transfer table 6, and these rollers 7 are mounted on bearings provided on the gear box 4 and the pellet transfer table 6, respectively. (not shown) is rotatably supported. A motor 8 is connected to a board 3 near the gearbox 4.
This motor 8
A group of gears (not shown) in a gear box 4 are connected to the rollers 4, and a large number of rollers 7 are linked to each other through this group of gears so that they rotate simultaneously in the same direction and at the same speed. A stainless steel pan 9 is provided below each roller 7.

Further, on the right side of the pellet transfer table 6 in FIG. 2, one bracket 10 and two brackets 11 spaced apart from each other and facing each other are attached to the base plate 3, respectively. A long hole 12 is formed in the bracket 11. Further, a tray vertical moving plate 15 having leg portions 13 and 14 is swingably attached to the bracket 11. That is, a pin 16 provided on the leg portion 14 is rotatably and slidably fitted into the elongated hole 12 of the bracket 11, and a motor 17 is attached to the bracket 10. As shown, the leg portions 13 of the tray vertically moving plate 15 are connected via a crank 18. This results in
When the motor 17 is driven to rotate, the tray vertically moving plate 15 swings about the pin 16 at a position slightly lower than the upper surface of the roller 7 via the crank 18 and moves to the second position.
It is arranged to move left and right in the figure.

Furthermore, tray guides 19 and 20 are attached to predetermined locations on the tray vertically moving plate 15, as shown in FIG. The tray guide 19 is made of a flat plate, and the tray guide 20 is a flat plate with a V-shaped groove 21 formed approximately in the center thereof. In addition, a tray guide 1 is provided at the edge of the upper surface of the tray vertically moving plate 15.
Stoppers 22 are provided corresponding to 9 and 20. A tray 23 is placed on the tray guides 19 and 20. As shown in FIG. 4, this tray 23 has an edge plate 25 and an end plate 26 attached to the end edge of a corrugated plate 24, and legs 27 having a substantially V-shaped cross section are attached to the lower surface of the edge plate 25. 2
It is attached corresponding to 0. Note that the tray 23 has the longitudinal direction of the valley of the corrugated plate 24 aligned with the roller 7.
It is placed facing in the direction of the extension of the axis. Further, the edge plate 25 is attached parallel to the longitudinal direction of the valley of the corrugated plate 24, and the end plate 26 is attached in a direction perpendicular to the longitudinal direction of the valley of the corrugated plate 24.
It is attached only to the opposite edge.

Further, a sixth
As shown in the figure, a pair of front and rear tray holders 28 are attached. That is, this tray holder 28 is rotatably attached to one attachment part 29 provided at the lower part of the tray vertically movable plate 15 and has a rotatable plate 31 having a handle 30, and a rotatable plate 31 that is rotatably attached to the rotary plate 31. a presser plate 33 that is attached to and has a handle 32;
A spring 34 is provided to bias this presser plate 33 in the direction of arrow A in FIG. moving plate 36;
A presser plate 37 rotatably attached to the rotary plate 36, a link 38 connecting the lower part of the presser plate 37 and the mounting portion 35, and two rotary plates 31, 3
6, and is configured so that the tray 23 placed on the tray vertical movement plate 15 can be pressed against the tray vertical movement plate 15 by the holding plates 33 and 37. There is.
Note that the extension line of each valley bottom line of the corrugated plate 24 of the tray 23 set on the tray vertical movement plate 15 with one end in contact with the stopper 22 is positioned in the middle between the rollers 7. It is configured.

Further, on the right side of the tray vertically movable plate 15 in FIG. 2, brackets 41 and 42 are provided upright on the base plate 3, facing each other and separated from each other. A guide bar 43 is provided between these brackets 41 and 42. As shown in FIG. 3, an extruded rod guide plate 44 having a large number of through holes is fitted into the guide bar 43 and attached to the bracket 41, and a large number of extruded rods 45 are inserted into the through holes.
An extrusion rod attachment body 46 having a shape is slidably fitted therein. The extension line of the axis of each extrusion rod 45 is positioned above the bottom line of the corrugated plate 24 of the tray 23. Further, a connecting plate 47 is attached to the bracket 42. A cylinder mechanism 48 is attached to this connecting plate 47, and the piston rod of this cylinder mechanism 48 is attached to the connecting plate 47.
The extrusion rod attachment body 46 is connected to the extrusion rod attachment body 46 through the extrusion rod attachment body 46 .

Further, brackets 51 and 52 are erected on the substrate 3 so as to be spaced apart from each other and are located to the right of the roller 7 and to the right of the push rod mounting body 46 in FIG. Two guide bars 53 are provided parallel to each other and spaced apart between the brackets 51 and 52. As shown in FIG. 1, arm guides 54 and 55 are slidably fitted into the guide bar 53. As shown in FIG. Arms 56 and 57 are fixed onto these arm guides 54 and 55, respectively. Arm 56,5
7 are connected by a connecting plate 58. Also,
A mask mechanism 76 is placed on the upper surface between the arms 56 and 57 as shown in FIG. In the mask mechanism 76, a pair of frame supports 79 of a frame 80 are rotatably engaged with a frame support shaft 78 that connects a pair of shaft supports 77 provided on a connecting plate 58, and a plurality of masks are attached to the frame 80. It has a structure in which a plate 81 is placed so as to be movable in parallel. The arm guide 54 is slightly extended downward, and a nut 59 is fixed to this portion as shown in FIG. Further, a feed screw support stand 60 is erected on the substrate 3 and positioned between the two guide bars 53 . This feed screw support base 60
A feed screw 61 is rotatably attached to the bracket 51 and the bracket 51.
This feed screw 61 is placed in the third position from the feed screw support base 60.
In the figure, it protrudes downward and is connected to a motor 65 mounted on the board 3 via pulleys 62, 63 and a belt 64. Connecting plates 66, 67 are attached to the arms 56, 57 in a hanging manner, respectively, as shown in FIG. On the front side in Fig. 1, there is a claw mounting rod 69.
is rotatably attached. A large number of bar-shaped claws 70 are provided on the outer peripheral surfaces of the claw mounting rods 68, 69 at predetermined intervals in the axial direction of the claw mounting rods 68, 69.
are installed in one row. Furthermore, a rotating arm 71 is attached to a predetermined location on the outer peripheral surface of one end of the claw attachment rod 69, as shown in FIG. This rotating arm 71 has a long hole 72 formed therein. Further, a cylinder mechanism 74 is attached to a predetermined location of the arm 57 via a mounting plate 73. A pin 75 is attached to one side of the piston rod of this cylinder mechanism 74.
5 is movably fitted into the elongated hole 72 of the rotating arm 71.

Next, the operation of this invention configured as described above will be explained.

When inspecting the outer surface of the nuclear fuel pellets 82 for cracks, chips, etc., (1) first inspect the tray 23 with a large number of nuclear fuel pellets 82 accommodated in the valleys of the corrugated plate 24 of the tray 23 in the direction of the valley bottom line; are placed on the tray vertical moving plate 15 with the axial direction of the roller 7 and the axial direction of the nuclear fuel pellets 82 aligned. (2) Next, the handles 30 and 32 of the tray presser 28 are operated manually to hold the tray 2 by the tray presser 28.
After one side of the tray 3 is brought into contact with the stopper 22, the tray 23 is pressed against the tray vertical movement side 15 by the presser plates 33 and 37. (3) Next, when the motor 17 is driven, the tray vertically moving plate 15 swings via the crank 18 and the legs 13, and the tray 23 in FIG.
The left end portion rests on the flange portion 5. Here motor 17
to stop. (4) Next, when the cylinder mechanism 48 is operated, the push rod 45 moves in the direction of arrow B in FIG. Push it toward the cm roller 7 side to align the end faces of each nuclear fuel pellet, and then move in the direction of arrow C and return to the original position. (5) Next, the motor 65 is driven, and the feed screw 61 is rotated via the pulleys 63, 62 and belt 64. As a result, arm 5
6 and 57 move, and the claw attachment rod 69 attaches the end plate 26 and the end plate 2 of the nuclear fuel pellet 82.
It stops directly above the end face on the 6th side. (6)
Next, the cylinder mechanism 74 operates and its piston rod moves in the direction of arrow D in FIG.
is rotated in the direction of arrow E in the same figure, and this rotation is stopped when the claw 70 reaches the position shown by the imaginary line in FIG. (7) Next, the motor 65 is driven again to rotate the feed screw 61, which causes the arm 5 to rotate.
6, 57 moves in the direction of arrow B in FIG.
A number of pawls 70 of the pawl mounting rod 69 engage the ends of each row of nuclear fuel pellets 82 arranged on the corrugated plate 24 and push them to place them on the intermediate portion of each roller 7. At this time, pellet transfer platform 6
Since the tray 23 is placed on top of the tray 23, each nuclear fuel pellet 82 can be transferred from the tray 23 onto the roller 7 very easily. (8) Arm 56,5
7 completes its movement in the direction of arrow B, the feed arms 56, 57 are slightly returned in the direction of arrow C. As a result, the 82 groups of nuclear fuel pellets are transferred to the arms 56 and 57.
It is located approximately midway between the (9) Next, the motor 8 is driven to simultaneously rotate each roller 7 in the same direction at the same low speed via the gears in the gear box 4. As a result, each nuclear fuel pellet 82 on the roller 7 simultaneously rotates in the same direction at the same low speed (rotational speed of about 10 rpm). Here, the operator sequentially moves the mask plate 81 of the mask mechanism 76 in parallel to see the nuclear fuel pellets 82 in a limited field of view that is not masked.
Visually inspect the outer circumferential surface of the At this time, the roller 7 can be stopped or rotated by a manual switch (not shown) at hand. In addition, defective nuclear fuel pellets 82 are introduced into the defective pellet inlet 3a using tweezers. (10) Next, drive the motor 17 to drive the second tray 23.
The left end in the figure is set below the flange 5 of the pellet transfer table 6. (11) Next, when the motor 65 is driven, the feed screw 61 rotates, and the arm 56,
57 moves in the direction of arrow C in FIG. As a result, the claws 70 of the claw attachment rod 68 engage with the nuclear fuel pellets 82 and push them, causing the rollers 7
Transfer from above onto tray 23. As a result, the arms 56, 57, the nuclear fuel pellet 82, etc. return to their original positions. At this time, since the end of the tray 23 is located below the flange 5 of the pellet transfer table 6, each nuclear fuel pellet 82 can be transferred from the roller 7 onto the tray 23 very easily. At this time, the cylinder mechanism 74 is activated to rotate the pawl mounting rod 69 in the direction of arrow F in FIG. 7 via the pin 75 and the rotating arm 71, thereby moving the pawl 70 to the position shown by the solid line in the figure. (12) Next, the motor 17 is driven, and the tray vertically moving plate 15 swings via the crank 18 and the legs 13, and stops when it reaches its original position.
(13) Next, the handles 30 and 32 of the tray holder 28 are manually operated to open the tray holder 28 and take out the tray 23.

As explained above, according to the present invention, on a plurality of rotating rollers rotating in the same direction above the base,
The end face of a rotating object to be inspected placed on a tray provided on one side of the roller is connected to an arm provided reciprocally between the tray and the roller and an object to be inspected attached to this arm. The arm of the transfer mechanism is equipped with a claw that presses the end face of the arm in the moving direction of the arm, and is transferred onto the roller by pressing the arm toward the roller. A mask mechanism that allows the object to be inspected to simultaneously rotate reliably in a predetermined direction at a predetermined speed, limits the field of view, blocks areas other than the field of view, and can move this field of view reduces eye fatigue for workers. In addition, the local exposure of the hands can be further reduced to approximately one-tenth of that of conventional methods.Furthermore, the field of view can be limited by the mask mechanism, making inspection easier, improving inspection speed, and shortening inspection time. Therefore, work efficiency is increased, thereby reducing the burden on the operator, and since there is no uneven rotation of the object to be inspected, inspection errors such as uneven inspection can be eliminated. Further, since the objects to be inspected on the tray are once transferred onto the rollers, even if there are fragments of the objects to be inspected remaining between the objects to be inspected or on the tray, these can be reliably separated and removed. Furthermore, since the object to be inspected can be rotated without applying an impact to the object, there is an effect that the object to be inspected is not damaged.

[Brief explanation of drawings]

Fig. 1 is a partially omitted front view showing one embodiment of the present invention, Fig. 2 is a view taken along the - line in Fig. 1, Fig. 3 is a view taken in the direction of Fig. 1, and Fig. 4 is a tray thereof. FIG. 5 is a view taken along the - line in FIG. 4, FIG. 6 is a schematic explanatory diagram of the tray holder, and FIG. 7 is a sectional view taken along the - line in FIG. 1. ,
FIG. 8 is a plan view showing the relationship between the mask mechanism and the arm, and FIG. 9 is a sectional view taken along the line - in FIG. 8. 1...Base, 4...Gearbox, 6...Pellet transfer stand, 7...Roller, 8, 17, 65
...Motor, 15...Tray vertical movement plate, 18...
Crank, 19, 20...Tray guide, 23...
...Tray, 28...Tray holder, 45...Pushing rod, 48, 74...Cylinder mechanism, 56, 57...
...Arm, 59...Nut, 61...Feed screw,
68, 69...Claw mounting rod, 70...Claw, 71...
Rotating arm, 76... mask mechanism, 81... mask plate.

Claims (1)

[Claims] 1. A base, at least a pair of rollers rotatably disposed above the base in the same direction, a rotational drive mechanism that rotates the pair of rollers in the same direction at the same speed, and a corrugated plate shape. The longitudinal direction of the valley on which the object to be inspected is placed is oriented in the direction of the extension of the axis of the roller, and the one side of the opened roller side is positioned at approximately the same height as the upper surface of the roller. a tray, an arm provided reciprocally between the tray and the roller, and a claw attached to the arm to press the end surface of the object to be inspected in the moving direction of the arm, a transfer mechanism for transferring a rotary object to be inspected placed on the tray from one of the tray and the base to the other; a transfer mechanism provided on the object to be inspected side of the arm to transfer the object to be inspected An apparatus for inspecting the appearance of an object to be inspected, characterized by comprising a mask mechanism that divides and limits the visual field of the object.