JPH0529247B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention provides a method for measuring the amount of can lid displacement.
This invention relates to an easy-open canned can leakage detection device for detecting leakage in canned foods.

BACKGROUND ART Conventionally, leakage inspection in a can production line has been carried out by measuring the amount of displacement of a can lid that changes as the internal pressure of the can changes due to leakage. For example, in the case of negative pressure canned goods, a normal can with no leaks has a can lid that is concave inward due to the negative pressure, but a defective can with leaks has a bulged lid. Therefore, by measuring the amount of displacement of the can lid, it is possible to determine whether or not the can is leaking. Conventionally, the amount of displacement of the can lid has been measured by arranging a proximity switch above the line conveyor and measuring the position of the can lid using the proximity switch. Pass/fail is determined based on whether the can is within a predetermined range, and defective cans are discharged to the outside of the line conveyor.

However, in the case of easy-open cans, which have recently become popular, the tab is within the measurement range of the proximity switch, so the measured value is very susceptible to the influence of the tab. Moreover, since the cans are conveyed on the conveyor and sent to the measurement position with the opening tabs oriented unevenly, the measured values vary depending on the position of the tabs at the time of measurement, and the same cans are measured several times. However, the measured values fluctuated each time, making accurate measurement difficult. Therefore, in the case of easy-open cans, it has been difficult to accurately distinguish between normal cans and defective cans using conventional leakage testing devices.

Problems to be Solved by the Invention The present invention was devised in order to eliminate the above-mentioned error in measuring the lid displacement position due to the uneven orientation of the opening tabs, and to realize accurate leakage testing of easy-open cans. Leak detection for easy-open cans, in which the tabs can be aligned in a predetermined direction with a simple device, and it is possible to accurately and easily distinguish between normal cans and defective cans without being affected by the tabs. The purpose is to provide a device.

Means for Solving the Problems In order to solve the above problems, the leak detection device for easy-open cans of the present invention supports the cans horizontally and rotates the cans in a fixed direction with its axis as the rotation axis. A turntable that rotates in a horizontal plane while applying a force, a tab stopper installed on the top of the turntable so as to be movable up and down within the range of the panel surface of the canned food, and a tab stopper that allows the canned food to move upward and downward within the panel surface of the canned food. a tab positioning device comprising a tab stopper vertical movement mechanism that lowers the tab stopper to a position close to the panel surface so that the tab stopper can come into contact with the tab side of the can lid and not contact the panel surface when placed on the can lid; A lid displacement detection sensor is placed above the passage of cans whose tabs are aligned in a certain direction by a positioning device, and detects the height position of the panel surface of the can.The can is positioned below the lid displacement detection sensor. a lid displacement amount detection device comprising an operation timing sensor that detects when the lid displacement amount detects the lid displacement amount and controls the operation of the lid displacement amount detection sensor;
When the tab stopper is lowered to a position close to the panel surface, the turntable is rotated one or more revolutions until it reaches a position below the lid displacement amount detection sensor, and the tab stopper up and down movement mechanism is configured to move the tab stopper downward. The tab stopper is pressed down with a force that does not impede the rotation of the canned food when it comes into contact with the top surface of the tab, and the tab stopper is moved from the tab engagement position at least until the canned food is removed from the turntable after the tabs are oriented. The structure is characterized in that it rises.

Operation The canned food supplied to the turntable 6 rotates together with the turntable. On the other hand, when canned food is supplied to the turntable, the tab stopper is lowered by the tab stopper vertical movement mechanism, and is held at a close enough position that it does not contact the can lid panel surface but engages with the tab t. . Since the tab on the can lid surface is raised above the panel surface, the tab hits the tab stopper as the can rotates, thereby preventing the can from rotating. As a result, the cans are held in that orientation by slipping on the turntable, and the orientation is aligned so that the tabs are always in the same position. As for the cans that are transported with the tab positions aligned in this way, the amount of displacement of the can lid is then measured by the proximity switch. At this time, since the tab directions are all aligned at a constant position, it is possible to eliminate variations in measured values due to differences in the tab directions. The amount of displacement of the lid is calculated based on the measured value, and it is determined whether or not it is within a predetermined range. If it is determined that the can is defective and outside the range, a reject signal is sent.

Example Examples of the present invention will be described in detail below.

FIG. 1 is a plan view of a leak detection device for easy-open cans according to an embodiment of the present invention.

In the figure, reference numeral 1 indicates an easy-open can, which is conveyed by a conveyor 2 from a pre-process of a can manufacturing line. Reference numeral 3 designates a main body turret, and a main body rotary disk 5 is provided below the main body turret and rotates in synchronization with the main body turret. As shown in FIGS. 2 and 3, a turntable 6 is provided around the periphery of the main body rotary disk, penetrating through the rotary disk and in the same phase as the can engaging recess 4 of the main body turret.
The turntable 6 carries canned goods and rotates around its axis to transport the canned goods. A tab stopper 8 of a tab alignment device is arranged above each turntable so as to be movable up and down. Further, as shown in FIGS. 4 and 5, a proximity switch of the can lid displacement detection device is arranged so as to be located above the rotation locus of the turntable at approximately 3/4 rotation position of the main body turret 3. There is. In the figure, 10 is a timing spiral, 11 is a supply turret that receives canned food from the timing spiral and supplies the canned food to the turntable 6, and 12 is a discharge turret that returns the canned food from the turntable 6 to the conveyor 2. A defective can discharging device 13 composed of an air cylinder or the like is provided along the conveyor 2 on the downstream side of the discharging turret. 1
Reference numeral 4 denotes a phototube for detecting cans provided immediately before the defective can discharging device.

As shown in FIGS. 2 and 3, the tab alignment device includes a turntable 6 on which the canned food 1 is placed.
The turntable 6 is composed of a tab stopper 8 and a tab stopper vertical movement mechanism.
It is fixed to and rotates as a unit. Tab stopper 8
is attached to a bracket 17 via a spring 16. The bracket 17 is fixed to a rod 18 attached to the main rotary disk 5 so as to be vertically movable. A cam roller 20, which is a cam follower of the cam 19, is provided at the lower end of the rod 18, and as the main body rotary disk 5 rotates,
The rod 18 is moved up and down by the cam 19. Accordingly, the tab stopper 8 is moved up and down. The spring 16, bracket 17, rod 18, cam 19, and cam roller 20 constitute the tab stopper vertical movement mechanism of this embodiment.

The lid displacement detection device is also best shown in FIGS. 4 and 5. In the figure, 22 is a proximity switch constituting a lid displacement detection sensor that detects the height position of the panel surface of a can, and is attached to the main body frame 26 via a bracket 23, a rod 24, and a holder 25 above the can passing position. ing. 27
are detection docks made of magnetic material attached at equal pitches to the outer periphery of the main body rotary disk 5, and 28
is a timing sensor that detects the detection dock and sends out an activation signal for the proximity switch. The timing sensor is composed of a proximity switch, and is fixed to the main body frame in such a position that the canned food is located just below the proximity switch 22 when the timing sensor detects the detection dog. In this embodiment, a proximity switch is used as the timing sensor 28, and a magnetic detection dog is provided accordingly, but a phototube may be used as the timing sensor and a detection mark may be used as the detection dog. Further, 29 is a can detection sensor that detects the presence or absence of cans on the turntable.

The easy-open canned leak detection device of this embodiment is constructed as described above and operates as follows.

Canned cans 1 with tabs, which are continuously conveyed by a conveyor 2, are made into a constant pitch by a timing spiral 10, and are fed onto a turntable 6 by a supply turret 11. The canned food supplied to the turntable 6 revolves around the outer periphery of the main turret while being rotated by the turntable.

On the other hand, the tab stopper 8 is connected to the turntable 6.
is in the raised position until no canned goods are supplied to it,
Canned food is supplied, and as the main rotary disk rotates, it is lowered by a cam mechanism and revolves while being held at a position close enough to engage the tab t without contacting the can lid panel surface. Since the tab t on the can lid surface is raised above the panel surface, the tab t hits the tab stopper 8 as the can rotates, thereby preventing the can from rotating. As a result, the cans are held in that orientation by slipping on the turntable, and the orientation is aligned so that the tabs are always in the same position. Note that since the tab stopper 8 is only slightly biased by the spring 16, if the tab stopper 8 rides on the tab t when descending, the rotation of the turntable will cause the tab stopper 8 and the tab t to
And slip. The turntable 6 is configured to rotate once while the main rotary disk 5 rotates 1/6, and the canned food transferred to the turntable 6 rotates more than once while being transported to the position A in FIG. 1. However, since the tab hits the tab stopper 8, rotation of the can is prevented, and the position of the tab is always constant at position A. Therefore, if the amount of displacement of the can lid is detected in the subsequent section, it can be measured at a position that is not affected by the tab, and measurement errors due to the tab can be eliminated.

For cans that are conveyed with their tabs aligned by the tab alignment device, the amount of displacement of the can lid is measured at the next position B. When the actuation timing sensor 28 detects the detection dog arranged at the same pitch as the turntable on the outer periphery of the main rotary disk 5, the can has just reached the position directly below the proximity switch, which is the detection position of the can lid displacement amount. timing sensor signal,
Measure the distance to the can lid at that time based on the can presence signal from the can detection sensor, calculate the amount of displacement of the lid based on the measured value, and determine whether it is within a predetermined range; If it is determined that the can is defective and out of range, a reject signal is sent.

The cans are then transferred onto the conveyor 2 by the discharge turret 12. If the cans transferred to the conveyor 2 are normal cans, they are conveyed as they are to the next process. However, cans that are determined to be defective by the can lid displacement device are discharged out of the line by a can discharging device 13 that is operated at a predetermined timing by a can detection sensor 14 based on a reject signal.

Effects The present invention is configured as described above, and since the orientation of the tabs of an easy-open can can be reliably aligned with a simple device, it is possible to completely eliminate measurement errors in the amount of displacement of the can lid due to the tabs. This has the remarkable effect that it is possible to accurately and easily distinguish between cans with normal can internal pressure and cans with defective cans.

[Brief explanation of the drawing]

The drawings show an embodiment of the leak testing device for easy-open cans according to the present invention, in which FIG. 1 is a plan view thereof, FIG. 2 is a side view of the tab aligning device, and FIG.
2 is a plan view of FIG. 2, FIG. 4 is a side view of the can lid displacement detection device section, and FIG. 5 is a plan view of FIG. 4. 1...Canned food, 2...Conveyor, 3...Main turret, 5...Main rotary disk, 6...Turntable, 8...Tab stopper, 10...Timing spiral, 11...Supply turret, 12...
Discharge turret, 13... Defective can discharge device, 14
... Phototube for can detection, 18 ... Rod, 19 ...
Cam, 22... Proximity switch, 26... Body frame, 27... Detection dog, 28... Timing sensor, 29... Can detection sensor.

[Claims]

1. A body that is fitted and fixed into the opening of the cover member, a disc-shaped code plate that is fixed to a rotary shaft that is rotatably attached to the axial center of this body, and the body that is opposite to this code plate. a detection element fixed to the code plate and detecting rotational displacement of the code plate;
A rotation sensor comprising a circuit board incorporating an output circuit that receives a rotational displacement signal of the code plate output from the detection element and outputs a signal corresponding to the rotational displacement, rotational speed, etc. of the rotation shaft. A guide portion having a cylindrical surface parallel to the rotation axis and a housing recess for the circuit board are formed in the body, and the circuit board is accommodated in the housing recess and is fitted and fixed to the body. A rotation sensor characterized in that a holding member for the detection element having a curved surface along a cylindrical surface of the guide part is fixed to the guide part so as to be adjustable in position in the axial direction of the guide part.

Claims (1)

Features a leak detection device for easy-open canned foods.