JPS6350746A - Apparatus for inspecting coated film on inner surface of can lid - Google Patents

Abstract

PURPOSE:To simultaneously inspect a plurality of can lids and to automate inspection, by sensing the insulating state of the inner surface of the can lid through an inspection liquid to detect the inferiority of a coated film. CONSTITUTION:An inspection liquid 5 is supplied into liquid tanks 3 in such a state that the opening parts of the liquid tanks 3 are turned upwardly. The inspection liquid 5 supplied to one liquid tank is uniformly supplied to all of the liquid tanks through liquid passing holes 6. Next, a can lid 10 is mounted on each of can lid engaging parts 8 and held under vacuum. An inspection tank 1 is reversed from this state to turn the opening parts holding the can lids 10 downwardly and the back surface of each can lid 10 is allowed to continue to each electrode 10 through the inspection liquid 5 and the surface thereof is contacted with each of the other electrodes 21. Voltage is applied between the electrodes 12, 21 in this state. When a coated film has an omission part such as a hole, a current flows between both electrodes 12, 21 through the inspection liquid 5 and the can lid 10 to detect the inferiority of the film. The mounting and discharge of the can lids 10 to the inspection tank 1 are performed by a robot and operation is performed by sequence control to make it possible to automate inspection.

Description

[Detailed description of the invention] Industrial applications The present invention relates to a coating film inspection device for the inner surface of a can lid.

BACKGROUND OF THE INVENTION A coating film of a certain thickness is formed on the inner surface of a can lid in order to prevent corrosion due to contact with the contents.

If there are even minute pores in this coating, the can lid will corrode through the pores over a long period of time, so it is required that two complete coating layers be formed.

Conventionally, as an inspection device for the inner surface coating of can lids, the can lid is set between opposing electric currents, and the outer surface of the can lid is inspected on one side. A known method is to apply a predetermined voltage between the electrode and the opposing electrode to detect a coating defect based on the presence or absence of a discharge current.

Then, the outer surface of the can lid is grounded as one of the electric conductors, and the back of the can lid is brought into contact with the surface of the liquid, which is the current-carrying medium.A voltage is applied between the outer surface of the can lid and the liquid, and the ejecting occurs depending on the presence or absence of current. Devices are also provided.

Problems to be Solved by the Invention However, the discharge i! is installed in a room gap. ! In the conventional method, it is difficult to properly discharge a voltage by applying a voltage smaller than the dielectric strength of the coating between the electric currents, and the reliability of the inspection is also poor. In addition, the method in which the inner surface of the can lid is brought into contact with the surface of the can body and a voltage is applied between the outer surface of the can lid and the liquid is more reliable than the above method, but inspection is performed manually one by one, so inspection is difficult. It is complicated, takes a long time, and has poor work efficiency, so automation is required.

The present invention was devised in view of the above-mentioned circumstances, and is a method for inspecting the inner surface of a can lid, which has high inspection reliability, can inspect multiple items at a time, and can be automated. The purpose is to provide a device.

Means for Solving the Problems The technical means of the present invention adopted to solve all the above problems will be explained based on the drawings of the embodiments.

That is, the apparatus for inspecting a coating film on the inner surface of a can lid according to the present invention uses a spray tank 1 divided into a plurality of liquid tanks 3 by a partition wall 2 in which a test liquid passage hole 6 and an air passage hole 7 are formed. It is pivotably attached to the frame 15 so that it can be turned upside down, a can lid engaging part 8 is provided at the opening of the liquid tank, and one electrode 12' is provided in the internal space near the opening. is provided so as to be able to come into contact with the surface of the can lid 10 held in the opening.

The test liquid is supplied into the liquid tank 3 with the opening of the working liquid tank 3 positioned upward. The test liquid supplied to one liquid tank passes through the liquid groove passage hole 6 and is evenly supplied into all the liquid tanks. Thereafter, the can lid is placed on the can lid engaging portion and held by the bachium. From this state, the test tank 1 is inverted, the can lid is held, the -fc opening is positioned downward, and the back surface of the can lid is electrically connected to the electrode 12 through the test liquid, and the surface of the can lid is connected to the electrode 2 of the pond.
1, a voltage is applied between the electrodes 12 and 21.

If there is a hole or other missing part in the coating film, a current flows between the two electrodes via the test liquid and the can lid, and by detecting the current, a coating defect is detected.

The above-mentioned inspection can be automated by using a robot to displace and discharge the can lid into the above-mentioned inspection tank, and by performing the above operations by sequence control.

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

1 and 2 are side views of an embodiment of the apparatus for inspecting a coating film on the inner surface of a can lid according to the present invention. FIG. 1 shows the state at the can lid set position, and FIG. 2 shows the state at the inspection position. Each state is shown.

In the figure, 1 is the inspection f! The liquid tank 3 is divided into a plurality of liquid tanks 3 by a partition wall 2. Each partition wall 2 is provided with a test liquid passage hole 6 and an air passage hole 7. In the can lid setting position (Fig. 1), the test liquid passage hole 6 is located at the end I
The test liquid 5 of each liquid tank 3 is adjusted so that the test liquid 5 such as water supplied to the water tank 3 flows into each liquid tank 3 and is supplied to each liquid tank at the same water level.
The test liquid 5 in each liquid tank 3 communicates with each other through the conduction hole 6, but in the tested position (FIG. 2), the test liquid 5 in each liquid tank 3 is located above the liquid level.
As shown in FIG.

In addition, the air passage hole 7 is arranged as shown in FIG. 4 so that the test liquid 5 in the liquid tank does not come into contact with it at any of the can lid set position, during the reversal of the container 1, and at the test position after the reversal is completed. It is provided at a position slightly shifted from the center 4 of the liquid tank 3 in the width direction in the counter-rotational direction. Thereby, it is possible to prevent the test liquid from being sucked by the pump and the pump during rotation, and to increase the amount of the test liquid 5 in the liquid tank 3. 8 is a can lid pad that is a can lid engaging portion provided at the opening of each liquid tank 3;
It is formed into a donut shape so as to engage with the shoulder portion of the can MIO, and becomes watertight when the can lid 10 is adsorbed as will be described later. In this embodiment, the test tank 1 is made of a plastic material to provide electrical insulation between the test tank and the can lid 10 and an electric rod (to be described later).

The electric barrier rod 11 penetrates the bottom of each liquid tank 3 and is located at the top of each liquid tank 3!
In the test position, the electric wire is submerged in the surface of the test liquid and conducts with the test liquid, and the power supply terminal 12 is connected to the power supply. .

The double-check tank 1 configured as described above is rotatably supported by the machine frame 15, and is driven by a motor or air means 16 via gears 17 and 18 to reverse it. Reference numeral 20 is a support shaft of the test tank 1 and also serves as a liquid supply pipe to the test tank 1. Reference numeral 21 denotes an electric wire 3 installed on the power terminal support stand 22 of the base frame 15, and as shown in FIG. It is located.

24 is a vacuum pipe attached to one side wall of the inspection tank 1 and is connected to a vacuum pump 25.

30 is a test liquid tank, and the liquid level is kept constant by a float valve or the like. 31 is a solenoid valve provided in the middle of the liquid supply pipe 32 to the inspection tank 1, and 34 is a pipe joint that rotatably connects the vibrators 32 and 20.

The paint film inspection apparatus for the inner surface of the can lid configured as described above detects defects in the coating film on the inner surface of the can lid as shown in the arrows.

The can lids 10 conveyed by the sampling conveyor 40 are sucked one by one from the stacking position 41 at the end by a robot 43 and placed one by one on the can lid pads 8 at the openings of each liquid tank 3. (See Figure 3).

On the other hand, the test liquid 5 is supplied from the test liquid tank 30 to the test tank 1 via the pipe 32.20.

In Figure 1, the liquid supplied to the leftmost liquid tank is connected to the partition wall 2.
The water is supplied to each liquid tank 3 through the liquid groove passage hole 6, and each liquid tank is brought to a constant water level. The water level of each liquid tank is determined by the water level of the test liquid tank 30, but the liquid is supplied to about 1/3 of the five liquid tanks 3 so that the liquid does not come into contact with the air passage hole 7 when each test tank 1 rotates. Ru.

When the liquid supply is completed in inspection @1, the solenoid valve 31 closes to cut off communication of the liquid. When the supply of the can lid 10 and the test liquid 5 to the test tank 1 is completed, the vacuum pump 25 is activated to suction and hold the can lid 10 to complete the setting.Then, the motor 16 is driven and the test tank 1 is It is rotated 180 degrees from the state shown in FIG. 1 and set to the inspection position shown in FIG. 2.

During half rotation of the test tank 1, the test liquid in the liquid tank 3 does not reach the air passage hole 7, as shown in Fig. 4 B) to ◇.
The test liquid does not move between the liquid tanks 3 through the air passage hole 7, and the vacuum state is maintained. In addition, at the inspection position after the inversion is completed, the liquid groove passage hole 6 is also located above the liquid level, so that the five test liquids in each liquid tank 3 are completely isolated from the liquid in the pond liquid tank, and electrically insulated. is planned.

If there is a pinhole or the like in the paint film on the back of the can lid, the electrical insulation will be broken, and a current will flow in the circuit of electric wire 11 - test liquid 5 - can lid 10 - θ terminal 21, and a not shown switch will be activated. death,
Paint film failure'Th can erupt.

The data is automatically processed by the data processing device.

When the spacing is completed, the motor 16 is driven again, and the test tank 1 returns to the state shown in FIG. 1 again. In this state, the vacuum is released and the inspected can lid 10 is removed from the inspection tank 1 by the robot 43.As described above, the present invention detects the insulation state of the inner surface of the can lid through the test liquid. Since it detects paint film defects, even small holes in the paint film can be reliably detected, resulting in high reliability. Also,
Since the can lid is simply placed at the opening of the inspection tank, t8
5. Easy to conduct inspection. Moreover, since a plurality of can lids can be inspected at the same time, the inspection can be carried out efficiently in a short period of time.

Furthermore, since robots can be easily used commercially for setting and discharging can lids, inspection can be automated.

[Brief explanation of the drawing]

Drawing e shows an embodiment of a coating film inspection device for the inner surface of a can lid according to the present invention. Fig. 1 is a side view in the can lid set position, and Fig. 2 is a side view in the inspection position. , Fig. 3 is a plan view, and Figs. 4 (a) to (e) are front sectional views showing the rotating structure of the liquid tank. 1: Sink tank 2: Partition wall 3: Liquid tank 5: Thrifty liquid 6:
Liquid groove passage hole 7: Air conduction hole 8: Nozzle 10: Can M 11: Electric rod 12: ■Electric drive 15: Machine frame 16: Motor 21: e-electro 25: Vacuum pump 30: Blue liquid tank 31 : [Magnetic valve patent owner Toyo Seijyo Co., Ltd. Applicant's agent Patent attorney Aya Sato Cf'k
or 2 people)

Claims (1)

[Claims] A test tank divided into a plurality of liquid tanks by a partition wall having a test liquid passage hole and an air passage hole is rotatably supported on the machine frame so as to be able to be turned upside down, and a can lid is engaged with the opening of the liquid tank. an inner space of the can lid, wherein one electrode is provided in the internal space near the opening, and the other electrode is provided so as to be able to come into contact with the surface of the can lid held in the opening. Paint film inspection equipment.