JPH0367157A - Flank inspection device for circular flat article - Google Patents

Abstract

PURPOSE:To simplify a driving device and to measure a flank without replacing any member even when a body to be inspected becomes small in size by equipping a flank inspection part with a means which conveys the body to be inspected at a vertical attitude, a friction belt which rotates the body to be inspected at a specific speed, and an image pickup device. CONSTITUTION:The inspection device is equipped with an attitude conversion part 10, the flank inspection part 30, and a selection part 50. The flank inspection part 30 drives a timing belt where a block 31 which has slots 32 as many as stripes of the passage of the attitude conversion part 10 for the body to be inspected is fitted with pins 33 by wheels 35 and 36 to convey tablets 3 to be inspected which are held in the slots 32 at the vertical attitude. Further, the friction belt 44 is installed below the block 31 so that its upper flank abuts on the lower parts of the tablets 3, and the belt is driven by pulleys 45 and 46 to rotate the tablets 3 so that their peripheral speed is faster than their conveyance speed. Then the linear image pickup device 41 picks up an image of the entire flank and a computer 60 analyzes the image to decide whether or not each tablet is normal.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention is a side inspection device for an article having a flat or nearly flat outer circumference, such as a tablet, and is particularly suitable for inspecting tablets. This invention relates to a side surface inspection device that processes a large number of processes per unit time.

(Prior Art) Conventionally, the surface inspection of flat or nearly flat articles with circular outer circumferences, such as tablets, has been carried out by inspecting the surface of an object by inspecting the object in a recess bored in two rotating drums installed adjacent to each other vertically or horizontally. The mainstream was to inspect the front and back using an imaging device, and the sides were not often inspected.

The first method of inspecting the side surface is disclosed in, for example, "Appearance Quality Inspection Method" in Japanese Patent Application Laid-Open No. 59-87081 filed by the applicant, and "Optical Sensor Device" in Japanese Patent Application Laid-Open No. 59-87082. A second method is to take an image of the subject on the conveyor belt using left and right television cameras.
There is a method disclosed in ``Appearance Inspection Apparatus'' in Publication No. 45, in which images of the left and right sides of the subject are captured by a single television camera using mirrors installed on the left and right sides of a conveyor belt. As a third method, for example, television cameras are placed at 45 degrees and 135 degrees with respect to the traveling direction of the conveyor belt, and images are taken of a 90 degree range of the opposing subject, with the conveyor belt as the center. There is also a method of arranging a mirror on the opposite side of the television camera to image a 90 degree range on the opposite side of the imaging range. As a fourth method, USA Patent No. 43300 2AND APPARATUS
FOR MEAS[JRING THE 5URFAC
E COI, 0ROF AN Al? By the method disclosed in TICLE J, four television cameras are combined into one
There is one that is arranged on a plane in four directions with one point as the center, and a subject is dropped into a passage in the center to image the side surface of the subject.

As a fifth method of rotating the subject to image it, there is a "Gi cup moving device" disclosed in Japanese Patent Application Laid-open No. 58-20280 filed by the applicant. A cup rotation device is installed, and a one-dimensional camera is used to image the inside of the paper cup from diagonally above. 6th
USA Patent No. 4,493,420) rMETI (
00 AND APPARATUS FOR DETE
CTINGBOIINDED REGIONS OF
IMAGBS, AND METIIOD ANDAP
PARATUs FOR 5ORTING AR
TICLES AND DETECTINGFLA
14S J and Specification No. 4308959 (7) r
ROLL s01? In the method disclosed in ``TING APPARATUS'', a plurality of friction rollers are rotated in a loop, a subject is held between the friction rollers and conveyed, and an imaging section provided in a part of the loop rotates a plurality of friction rollers. The object is rotated by causing it to rotate,
Some images are taken from above using a television camera.

Seventhly, in the method disclosed in Japanese Patent Application No. 63-152373 "Side surface inspection device for circular flat article" filed by the applicant, a plurality of friction rollers are rotated in a loop like the sixth method. First, the imaging section installed in a part of the loop images the subject rotating on the friction roller.Furthermore, in the imaging section, a friction heald is installed below the friction roller to allow the subject to rotate faster. , and image the side of the subject with a -dimensional imaging device,
We are trying to increase the resolution of the subject image.

(Problems to be Solved by the Invention) A side surface inspection device must be able to inspect the entire side surface, do not cause shading or halation over the entire inspection surface, and obtain a high-resolution, high-quality screen. be. Furthermore, increasing the throughput per unit time (hereinafter referred to as "high throughput capacity"), for example, in the tablet inspection apparatus described in the embodiments of the present invention,
It requires processing of 120,000 pieces per hour (approximately 33.4 pieces per second).For this reason, the structure is such that the required number of processing units of the same mechanism can be operated in parallel depending on the number of pieces processed per unit time. (hereinafter referred to as "multi-filament structure"), and the processing unit itself is capable of high-speed processing (hereinafter referred to as "high-speed processing capability").
That's what it means. )Is required.

Examining the prior art from these viewpoints, the first method has an imaging range that covers 180 degrees of the side of the object, so it is not possible to image the entire area, shading increases around the screen, and it is not suitable for multi-striped structures. There is a problem. Although the second method has the advantage of requiring only one callan, it cannot avoid the same drawbacks as the first method. In the third method, the imaging range is narrowed to 90 degrees, so the image quality is improved, but it requires two cameras and is not suitable for a multi-line inspection device. The fourth method is unique and can obtain good images over the entire side surface, but it requires four cameras, which complicates the device, and is not suitable for multi-strip inspection devices.

The fifth method, in which the object is placed on a rotary table and imaged, allows a complete side inspection, but is not suitable for multi-striped methods and lacks high-speed processing capability.

The sixth method, in which the specimen is rotated by being held between rotating friction rollers, has a large throughput capacity and is suitable for a multi-strip structure, and is also an excellent transport method. The shape is not limited, and the structure is such that the object to be inspected is held between friction rollers and conveyed, and the object is imaged as is with a television camera, so it is suitable for inspecting the sides of circular flat articles such as tablets. cannot be used.

The rotation speed and rotation method of the friction roller are disclosed in U and S Patent No. 4.
Although not explicitly stated in the specification of No. 493420,
No. 4,308,959 discloses a method in which a friction roller is brought into contact with an upper portion of a fixed friction member within an imaging range. Therefore, the peripheral speed of the subject is approximately the same as the running speed of the friction roller loop,
When the radius of the object is r, the friction roller loop is 2πr.
When running, the subject rotates once. This is fine if the imaging device is a television camera that can perform two-dimensional imaging, but to increase the resolution, for example, a multi-element COD
A one-dimensional imaging device having a line sensor has a problem in that it is unable to image all sides of the subject.

Claims (1)

[Scope of Claims] 1. A posture changing unit that converts a subject, which is a circular flat article, from a flat posture to a vertical posture; and a posture converting unit that rotates the subject whose posture has been changed vertically and captures the side surface of the subject using an imaging device. In a side surface inspection device for circular flat articles, which includes a side surface inspection device that performs imaging and inspection, and a sorting section that separates non-defective products and defective products based on the inspection results, the side surface inspection section maintains the subject in a vertical posture. means for transporting the subject; a friction belt that directly contacts the subject transported to a position on the transport means that includes the imaging range and rotates the subject at a predetermined speed; 1. A side surface inspection device for a circular flat article, comprising: an imaging device that captures an image of a certain object. 2. The conveyance means includes a plurality of blocks having a thickness slightly thicker than the radius of the subject, and a timing belt for attaching the blocks in a loop, and each block has a width slightly larger than the thickness of the subject. A plurality of rows of notches that are slightly wider and have a depth larger than the radius of the object to be examined are provided, and the distance between the depth surface of the notch and the wall surface of the next block is slightly wider than the diameter of the object to be examined, and the interval between blocks is provided. 2. The side surface inspection device for a circular flat article according to claim 1, wherein the thickness of the circular flat article is smaller than the thickness of the object to be inspected. 3. The conveyance means has a belt having a thickness greater than the radius of the subject, and the belt has a plurality of through holes having a length slightly longer than the diameter of the subject and a width slightly wider than the thickness of the subject. 2. The side surface inspection device for a circular flat article according to claim 1, wherein the device is arranged in a matrix. 4. The traveling speeds of the conveyance means and the friction belt are V_1 and V_2, respectively, the power transmission coefficient between the friction belt and the subject is k, and the imaging direction is the straight line connecting the imaging point of the subject and the center of the subject. When the angle formed by θ is θ and the radius of the object is r, if the conveyance direction of the conveyor belt and the running direction of the friction belt are reversed, the running speed is V_2/V_1
= (π-θ)/ksinθ, and if they are the same, V_2/V_1=(π+θ)/ksinθ.
The side surface inspection device for a circular flat article according to any one of claims 1 to 3, wherein an image is captured in a range indicated by rsinθ.