JPH0435802Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field The present invention relates to a device for determining the front and back sides of a can, and particularly to a device for determining the front and back sides of a can whose top outer diameter and bottom outer diameter are different.

BACKGROUND ART Conventionally, in the manufacturing process of canned goods, canned goods discharged from a retort device after heat sterilization have uneven front and back sides, and it is necessary to transport them to the next process such as packaging with the front and back sides aligned. Therefore, for example,
As described in Japanese Patent No. 31432, the front and back sides of the cans are determined, and based on the results, the cans are aligned and sent with their fronts and backs aligned. Conventionally, the can front/back discrimination device used in such a can alignment device generally uses a photoelectric sensor to detect the presence or absence of marks, letters, etc. engraved or printed on the lid surface of the can during transportation. This is used to distinguish between the front and back of a can, but the detection accuracy is affected by the quality of the engraving.
In addition, there is a drawback that misidentification is likely to occur due to moisture or scratches on the can lid, or swelling of the can lid immediately after heat sterilization.
Therefore, in order to eliminate these drawbacks and further improve the detection accuracy, it has been proposed that multiple phototubes, for example three phototubes, be arranged diagonally with respect to the lid of the can to be detected. (Japanese Patent Publication No. 60-178118).

Problems that the invention aims to solve The conventional method for detecting the front and back sides of cans has the above drawbacks because it detects the markings on the can cover surface. A device that tilts the optical axis has been proposed, but the adjustment of the tilt angle is delicate and requires skill, and it also requires multiple photoelectric sensors, making it expensive.

The present invention avoids the drawbacks of the conventional can front/back detection devices, and provides a front/back discrimination device that is reliable in detection, has a simple configuration, and is suitable for determining the front/back of a can whose top and bottom outer diameters are different. The purpose is to

Means for Solving the Problems The present invention attempts to distinguish between the front and back sides of a can by utilizing the difference in the outer diameters of a can where the outer diameters of the top and bottom are different. This was done by focusing on the intensity of the reflected light due to the difference in the reflection distance from the light source by projecting light from above during the period of time.

That is, in order to solve the above-mentioned problem, the front/back discriminating device of the present invention installs a light source and its reflected light above the conveyor 3 that conveys cans with different top and bottom outer diameters in an aligned state. A photoelectric sensor 5 having a photodetecting section for detection is located in a range where the optical axis of the photoelectric sensor is parallel to the can axis and is divided by the top outer periphery and the bottom outer periphery of the can 1 conveyed by the conveyor 3. We adopted a method of arranging them so that

Function: By projecting light from directly above onto the range defined by the difference between the top outer diameter and the bottom outer diameter of the can being transported on the conveyor, the diameter-reduced top is placed on top. The light emitted from the photoelectric sensor is projected downward without being blocked by the top of the can, but the amount of light hardly reaches the seam at the bottom of the can, and almost no reflected light is detected. On the other hand, if the bottom, which has a larger diameter, is facing upward, strong reflected light will be detected because it will be blocked by the bottom of the can. By detecting the strength of the reflected light, it is possible to determine whether the can is front or back.

Embodiments Hereinafter, embodiments of the front/back discriminating device of the present invention will be described in detail with reference to the drawings.

In the figure, reference numeral 1 denotes a one-sided neck-in can whose diameter is reduced only on one side (top), which is an example of a can whose top and bottom have different outer diameters and whose front and back sides are to be detected by the device of the present invention. Reference numeral 2 denotes a conveyor such as a belt conveyor for conveying the cans 1. The cans 1 are guided by guides 3 and 3' on the conveyor and conveyed in a line.

5 is a photoelectric sensor, which is composed of a reflective phototube equipped with a light source and a light receiving element. The photoelectric sensor 5 is mounted on a mounting bracket 6, and the mounting bracket 6 is supported on a support rod 7 by mounting screws 9, 9 fitted in long grooves 8, 8' so as to be adjustable in position. Thereby, the photoelectric sensor 5 projects light onto the area outside the outer periphery of the top 1' of the can 1 and inside the outer periphery of the bottom 1'' of the can 1, where the light from the photoelectric sensor is conveyed on the conveyor 3, that is, on the reduced diameter part. As you do,
It is set by adjusting its position in the width direction of the conveyor. Further, the height of the photoelectric sensor 5 can be adjusted by making the support rod 7 freely adjustable in the height direction.
Alternatively, appropriate means can be adopted, such as attaching the photoelectric sensor 5 to the bracket 6 so as to be adjustable in the height direction.

The front and back sides of a can are detected in the following manner by the can front and back side detection device configured as described above.

When the single-sided net-in cans 1, which are aligned and conveyed by the guides 3 and 3' on the conveyor 2, are in the top-up state as shown in the figure, the light from the photoelectric sensor 5 is directed toward the top of the can. The light is projected downward without being blocked by the can, but the amount of light hardly reaches the seam at the bottom of the can, and the reflected light is so weak that it is almost undetectable, allowing it to be detected that the can is in the open position. . On the other hand, if the bottom with the larger outer diameter is in the back position, the light emitted from the photoelectric sensor is immediately reflected by the can lid, so the reflected light becomes stronger and it is determined that the bottom is in the back position. .

The cans determined to be in the face-down state are then reversed by an appropriate reversing means, aligned in the face-up state, and conveyed to the next process.

Effects The device for distinguishing the front and back sides of a can is constructed as described above, and as a result of utilizing the reduced diameter of the can, the strength of the reflected light when the can is in the front state and in the back state is different from that of the conventional case. Since it appears more clearly than other methods that detect markings on the surface of can lids, detection can be performed reliably with a single photoelectric sensor. In addition, unlike conventional methods, it is not affected by the quality of the engraving on the can lid surface, moisture or scratches on the lid, or swelling of the can lid, so there is no chance of misidentification due to these factors. do not have. Furthermore, since it can be detected with just one photoelectric sensor,
It has the advantage of being simple in structure and inexpensive to manufacture.

[Brief explanation of the drawing]

FIG. 1 is a front view of an embodiment of the can front/back detection device according to the present invention. 1... One side net-in can, 2... Conveyor, 3, 3'... Guide, 5... Photoelectric sensor,
6...Bracket, 7...Support rod.

Claims (1)

[Scope of utility model registration request] This is a device for distinguishing the front and back sides of cans having different top and bottom outer diameters, and includes a photoelectric sensor having a light source and a light detection unit that detects the reflected light above a conveyor that conveys the cans in an aligned state. , the photoelectric sensor is arranged so that its optical axis is parallel to the can axis and located in a range defined by the top outer periphery and the bottom outer periphery of the can conveyed by a conveyor. Device.