JPH01295154A - Automatic inspecting device for film defect on internal surface of can - Google Patents

Abstract

PURPOSE:To obtain an automatic inspecting device which saves the labor by mechanizing all of operations for inspecting a film defect on the internal surface of the can such as the stopping of the metallic can on a conveyance path, the filling of the can with electric feeding liquid, and the contacting of an electrode and taking-in/out operation. CONSTITUTION:The device consists of a fixed base 1, an intermediate driving rotary disk 3 which has numbers of can bottom part fall holes arranged at specific intervals, an electric feeding liquid filling nozzle 4 above a 1st can stop position A set on the can conveyance path, an elevation upper electrode rod 5 arranged above a 2nd can stop position B, an elevation lower electrode rod 6 which comes into contact through an opening part 11 provided to the fixed base 1 below the 2nd can stop position B, a can discharge base plate 7 which is provided below a 3rd can stop position C and pushes out the can X by slanting to outside of the rotary disk 3, a power source, and a current detector. Then a current is detected after a voltage is applied for a specific time, and then the film defect of the can is detected automatically.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application This invention relates to an automatic inspection device for coating defects on the inner surface of a can.

Conventional technology Since some contents corrode the can opening, a synthetic resin coating is provided on the inner surface of the can for corrosion protection. However, depending on the state of the coating, there may be defective products with pinholes or the like in the coating film. For this reason, devices have been known that electrically inspect the coating film on the inner surface of a can for defects.

The conventional device includes a platform having a shallow inverted U-shaped cross section with a hole for fitting the bottom of the can, a hollow column erected at one end of the platform, and a vertical metal rod inserted into the hollow column so as to be able to move up and down. A flat metal ice rod is fixed to the upper end of the vertical rod, an upper electrode rod is attached to the tip of the horizontal rod and looks into the hole at the bottom of the can, and a bracket is mounted on the bottom of the stand, which is pivoted at the center. a lower electrode rod attached to one end of the lever below the fitting hole in the bottom of the can, a weight attached to the other end of the lever that biases the lower electrode rod upward, and both electrode rods. Equipped with a power source that applies a voltage and a current detector that detects the value of the current flowing between the image electrodes, the value of the current flowing between both electrodes is compared with a reference value after a predetermined time has passed after applying the voltage. It is something to do. If there is a defect in the paint film, a lot of current will flow, but if it is normal, almost no current will flow.

Problems to be Solved by the Invention In the conventional device, a can is first filled with a current-carrying liquid, then the can is inserted into a can bottom fitting hole in a stand, and after the bottom electrode is brought into contact with the bottom of the can, a vertical rod is temporarily inserted into the hollow. The upper electrode rod had to be inserted into the energizing liquid inside the can after being pulled up from the pillar, which was cumbersome because all of this was done manually.

An object of the present invention is to provide an automatic inspection device for coating defects on the inner surface of a can that eliminates all of the above-mentioned troubles.

Means for Solving the Problems In order to achieve the above object, the automatic inspection device for coating defects on the inner surface of cans according to the present invention includes a fixed table and a number of can bottom fitting holes arranged above the fixed table. An intermittent drive rotary plate provided at intervals, an energized liquid filling nozzle located above a first can stop position set on the can transfer path, and an energized liquid filling nozzle located above the second can stop position. An ascending and descending upper electrode rod that is inserted into the energized liquid in the can for a predetermined period of time, and an ascending and descending section electrode that is placed below the second can stop position and is brought into contact with the bottom of the can for a predetermined period of time through an opening provided in the fixing base. and a can discharge base plate which is disposed below the third can stop position and which pushes up the can bottom through an opening provided in the fixed base and tilts the can bottom to knock the can out of the rotary plate. , a power source that applies a voltage to both electrode bars, and a current detector that detects the current flowing between the picture electrode bars.

Example Embodiments of the invention will be described below with reference to the drawings.

The automatic can inspection device for coating defects on the inner surface of cans shown in Figs. An intermittent drive rotary plate (3) provided at every interval, an energized liquid filling nozzle (4) placed above a first can stop position (A) set on the can transfer path, and a second can stop The lifting upper electrode rod (5) is placed above the position (B) and inserted into the energized liquid in the can for a predetermined period of time, and the fixing base (5) is placed below the second can stop position (B). 1) provided in the opening (11
) through which the electrode rod (6) of the lifting part is brought into contact with the can bottom for a predetermined period of time, and through the opening (11) located below the third can stop position (C) and provided in the fixing base (1). A power source that applies voltage to the can discharge base plate (7) that pushes up the can bottom and tilts it to knock the can (X) out of the rotary plate (3), and both electrode rods (5) (B). (8) and a current detector (9) that detects the current flowing between both electrode rods (5) and (6). The value of the current flowing through the sensor is compared with a reference value.

The fixed base (1) is supported on a circular base casing (12) containing the pump and drive mechanism. base·
The casing (12) is placed on a liquid receiving tray (15) having a liquid drain port (14) via a spacer (13). The rotating plate (3) is formed in an annular shape, and is provided separately at the center of the base casing (12) and at the lower edge of the outer periphery of a circular upper casing (17) having a top wall (16). connected. An internal gear (62) is provided on the lower edge of the inner circumference of the upper casing (17), and a drive gear (63) is meshed with the internal gear (62). The centers of the multiple can bottom fitting holes (2) are arranged so as to be located on the center line of the annular rotary plate (3). Energized liquid filling nozzle (
4) is fixed via an arm (19) to a column (18) that penetrates the top wall (16) of the upper casing (17) and projects upward, and its upper end is attached to the pump. It is connected to the connected hose (20). The upper electrode rod (5) is attached to the top wall (1) of the upper casing (17).
It is fixed via a mounting arm (22) to a lifting rod (21) that penetrates through the lifting rod (21) and protrudes upward through the lifting rod (21).
21) is the piston rod (
(not shown). A lead wire (23) leading to the power source (8) is connected to the upper end of the upper electrode rod (5), and a downward truncated head for liquid level adjustment, which will be described later, is connected near the lower end of the upper electrode rod (5>). A cone (4) is attached.

As is clear from FIG. 3, the lower electrode rod (6) is connected to the column (
It is fitted into a vertical through hole (27) drilled in the inner end of a one-character lever (26) pivotally attached to the upper end of the lever (25) in an upwardly projecting manner, and is fixed by a set screw (28). A lead wire (30
) terminals are clamped.

A block-shaped weight (
31) is fixed by a set screw (32).

A fixed base (33) is provided on the outer surface of the column (25), and an upward hydraulic cylinder (34) is supported on this. A stopper (36) is provided at the tip of the piston rod (35) and extends to the lower surface of the weight side of the lever (26), and when the piston rod (35) is at its protruding limit, the lever (26) can be lifted until it is just right. It is made to be horizontal.

As is clear from Figure 4, the can discharge base plate (7) is connected to the top wall (3).
7), and is swingably attached to the cylinder (38) by a hinge (39) at its outer end. An upward hydraulic cylinder (4o) is arranged below the cylindrical body (38). A movable bottom cover (42) is fitted to the lower end of the inner periphery of the cylindrical body (38) so as to be able to move up and down. 44), it is integrally fixed to the base of the piston rod (45) in the retracted state. A through hole (46) is bored in the center of the top wall (37) of the cylindrical body (38), and the tip of the piston rod (45) is inserted into the hole to connect the bottom can discharge base plate (7). ). A compression coil spring (47) is interposed between the movable bottom cover (42) and the top wall (37), and this is connected to the piston rod (
45) is fitted. A horizontal protrusion (59) projecting outward is provided at the lower end of the peripheral wall of the cylindrical body (38). At the upper end of the peripheral wall of the fluid pressure cylinder (40), legs (
61) is fixed. The can discharge base plate (7) is made of a disc having a diameter slightly smaller than the diameter of the can bottom, and the circular opening (11) of the fixing base (1) through which it passes is located at the edge of the can bottom. It has a diameter (width) that can receive the can and allow the can discharge base plate (7) to pass through. In addition, in this example, the second can stop position (B) and the third can stop position (C)
The openings (11) are both circular and independent, but they may be continuous long holes.

A discharge can storage device (48) is arranged at the third can stop position (C) (see Figures 1, 2, and 4).
. The discharge can storage device (48) has a wall body (49) with a U-shaped vertical cross section and a U-shaped horizontal cross section, and a can (X) that receives the can (X) that has been knocked over with its mouth facing down outside the rotary plate (3). , a chute (5o) for sliding this down, a bottom plate (51) connected to the lower end of the chute (50) and sloped to one side, and a hinge (52) on the wall (49) on the sloped side of the bottom plate (51). ), and the piston φ rod (54) is attached to the upper end of the door (53), and the piston φ rod (54) is attached downward to the wall (49) above the door (53). The fluid pressure cylinder (55) is located below the door (53) and the can receiving box (56) is provided on the outside of the wall (49).
).

A liquid outlet (57) is provided at the bottom of the wall (49).

Next, the operation for inspecting paint film defects on the inner surface of a can will be explained.

In Figure 1, all the holes (2) in the rotating plate (3) are
It is assumed that the bottom of the can (X) has been fitted and the rotating plate (3) is intermittently driven counterclockwise in the drawing.

All cans (X) up to the first can stop position (A) are empty. Of course, it is not necessary that cans (X) exist in all the holes (2) of the rotary plate (3), and there are always empty cans in at least one hole (2) before the first can stop position (A). All you have to do is make sure that exists.

In the above state, as the rotary plate (3) rotates, when the empty can (X) that has been transferred by sliding on the upper surface of the fixed base (1) stops at the first can stop position (A), the filling nozzle ( 4) The energized liquid is filled into the can (X). At this time, as shown in Figure 7 (a), the liquid level (58A) is lower than the can (X
) The injection of the energizing liquid is stopped when the energizing liquid is located slightly below the upper end.

When the can (X) is filled with energized liquid until it reaches the top of the can (X),
) may spill while being transferred from the first can stop position (A) to the second can stop position (B). If it spills, it will not be possible to detect any defects in the coating film at the upper end where the current-carrying liquid is not present. Note that saline is used as the energizing liquid.

The can (X) filled with energized liquid is at the second can stop position (B
). During the stop, the upper electrode rod (5) is inserted into the energized liquid of the can (X), and the lower electrode rod (6) is brought into contact with the bottom of the can. When the upper electrode rod (5) is inserted into the current-carrying liquid, the downward truncated cone (24) attached thereto also enters the current-carrying liquid. As a result, the volumetric liquid level of the cone (24) rises, and the liquid level (58B) comes to the upper end of the can (X) as shown in FIG. 7(B). The upper electrode rod (5) is lowered by retracting a piston rod of a hydraulic cylinder (not shown). The rise of the lower electrode rod (6) is caused by the piston rod (3) of the hydraulic cylinder (34).
5). That is, when the piston rod (35) is retracted, the - lever (22) loses its support from below, so the gravity of the weight (31) on its outer end causes it to move as shown in Fig. 3. The horizontal state shown by the solid line changes to the inclined state shown by the chain line, and the lower electrode rod (6) on the inner end side rises. Keep the upper and lower electrode rods (5) (6) in this state for a predetermined time, apply voltage to both electrode rods (5) (8), detect the current with the current detector (9), and detect after the predetermined time has passed. Compare the current value with the reference value.

The can (X
) is transferred to the third can stop position (C).

When the can (X) stops here, the hydraulic cylinder (40)
The piston rod (45) is made to protrude.

Then, the cylindrical body (38) and the can discharge base plate (7) also rise together with the piston rod (45), and the upper end of the can discharge base plate (7) aligns with the hole (2) of the rotary plate (3). When it protrudes a little further, the horizontal protrusion (
59) comes into contact with the stopper (60) from below. As a result, the cylindrical body 38) stops at that position, but the piston
The rod (45) still protrudes. At this time, the movable bottom cover (42) rises together with the piston rod (45), so between this and the top wall (37) of the cylindrical body (38),
The coil spring (47) is compressed. Then, the piston
The tip of the rod (45) is connected to the top wall (37) of the cylindrical body (38).
) and push the can discharge base plate (7) upward from the hinge (
39) as a fulcrum, tilt the bottom of the can, knock the can (X) out of the rotary plate (3), and transfer it to the chute (50) of the discharge can storage device (48). Change. When the can (X) falls over, the energized liquid inside flows out of the can. When the can (X) is ejected, the piston rod (4
5) will be removed and everything will be restored to its original state.

When the can (X) passes through the shoe (50) and reaches the bottom plate (5I), the piston rod (54) of the hydraulic cylinder (55) is retracted and the door (53) is opened upward. Then, the can (X) rolls along the slope of the bottom plate (51) and enters the can receiving box (56). The empty cans (X) that have entered the can receiving box (56>) are sequentially moved to a predetermined location.By the time the next can (X) arrives on the bottom plate (51), the piston rod (
54) is made to protrude and the door (53) is closed.

In addition, the first, second and third can stop devices (A) (B)
A can sensor is disposed at (C), and by detecting the arrival of a can, a quantitative filling device, a fluid pressure cylinder, etc. are activated.

Effects of the Invention According to the automatic inspection device for coating defects on the inner surface of a can according to the present invention, filling of the energizing liquid into the can and inserting and removing the upper electrode rod from the energizing liquid in the can are all carried out automatically, which saves time and effort. Ministry is very convenient.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention; FIG. 1 is a plan view, FIG. 2 is a partially cutaway side view, and FIGS. 3 and 4 are taken along lines ■-■ and IV in FIG. 1, respectively. Figure 5 is an electric circuit diagram for current detection, and Figure 6 shows the can, the upper electrode rod with a downward truncated cone, and the lower electrode rod, showing the state before and after adjusting the energized liquid level. FIG. 3 is an enlarged vertical cross-sectional view. (1)...Fixing stand, (2)...Can bottom fitting hole, (
3)...Intermittently driven rotary plate, (4)...Electrifying liquid filling nozzle, (5)...Upper electrode bar, (6)...Lower electrode bar, (7)...Can discharge stand Board, (8)...Power supply, (9
)... Current detector, (11)... Opening, (A).
...First can stop position, (B)...Second can stop position, (
C)...Third can stop position. Patent applicant: Showa Aluminum Can Co., Ltd. (A) No.

Claims (1)

[Claims] A fixed base (1), an intermittent drive rotary plate (3) disposed above the fixed base and having a number of can bottom fitting holes (2) at predetermined intervals, and a first rotary plate set on the can transfer path. Energized liquid filling nozzle (4) located above the can stop position (A)
and an elevating upper electrode (
5), and a lifting part electrode rod (6) which is placed below the second can stop position (B) and is brought into contact with the can bottom for a predetermined period of time through an opening (11) provided in the fixing base (1). ,
The can bottom is pushed up and tilted through an opening (11) located below the third can stop position (C) and provided in the fixed base (1), and the can (X) is moved to the rotating plate ( 3) Can discharge base plate (7) that is pushed out of the box and both electrode rods (5) (6)
A power source (8) that applies voltage to the electrodes (5) and (6)
An automatic inspection device for coating film defects on the inner surface of a can, which is equipped with a current detector (9) that detects the current flowing between the cans.