JPH01317582A - Focusing structure of information reader - Google Patents

Abstract

PURPOSE:To improve durability by allowing a light path bending section provided with a pair of mirrors consisting of two reflecting mirrors, the reflection surfaces of which are opposed at a specified angle, to exist in the light path. CONSTITUTION:A display sheet 51 which indicates sorting information such as an address attached to the upper surface of an object 50 transported by a conveyor 10 is read by a camera section 20 and an information processing section through a fixed mirror (b) and a moving mirror section 30. The control section of an automatic sorting device transports, collects and sorts the object for different directions by address and destination, based on the information which is read. The display sheet 51 is attached to the upper surface of the object 50 to be transported by the conveyor 10. Thus the sorting operation is performed efficiently.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application J] The present invention is a sorting device that automatically performs j1-minute work on conveyed packages, mail, etc.! The present invention relates to a focusing structure of an information reading device used for reading information displayed on objects (such as packages and mail).

[Prior art] From a rental vehicle, packages and mail are sent to a circularly driven conovair, etc., and the conveyed items (packages, mail, etc.) are automatically transported according to their destination and destination. There is an automatic sorting device for sorting.゛In such an automatic sorting device, information such as destination and destination displayed on the outside of the conveyed object is read by a reading device installed near the conveyor, and based on this read information, the conveyed object on the conveyor is sorted. The destination and destination are transported and collected in different directions and sorted.

The reading device that reads information displayed on conveyed items consists of a camera section made up of an optical system (lens), a sensor, and an electric circuit, and an information processing section made up of a microcomputer.

In the camera section, the image of the information display section formed on the sensor surface by the lens is converted by the sensor into an electrical signal and output to the information processing section.The information processing section uses pattern recognition etc. to generate information based on the signal from the camera section. It is designed to read.

Note that if the size of the cut object is not constant and the camera section is fixedly installed, the distance from the information display section of the conveyed object to the camera section will change and the image will no longer be formed on the sensor surface, making accurate reading impossible. In such cases, the camera section may be configured to be movable, and the distance from the information display section of the conveyed object to the camera section may be measured using a 114-station device to automatically move the camera section. The operator moves the camera section by visual measurement so that the distance from the information display section to the camera section is constant.

[51111 of Confucian Song technology] However, as mentioned above, the camera part is composed of a highly accurate optical system (lens), sensor, and electric circuit, and the size of the conveyed object is amorphous, so the camera part cannot be seen from the information display surface. If the distance to the camera part changes frequently, the camera part must be moved frequently. As a result, the camera part is prone to failure due to vibrations and shocks caused by moving and stopping, and there are problems with poor durability. be.

In addition, when sorting, it is desirable to increase the conveyance speed of conveyed items as much as possible in order to improve the work efficiency, but it is important to consider the durability mentioned in Iij and the ability of the camera section to withstand relatively large ft loads. Therefore, there is a limit to the moving speed due to inertia, and the moving speed of the camera unit restricts the conveying speed of the conveyed object, which impedes the improvement of work efficiency.

[Objective of the Invention] In view of the above-mentioned circumstances, the present invention provides an information reading system that allows focusing without moving the camera section, has high durability, and increases the conveyance speed of conveyed objects. Its purpose is to provide a focusing structure for positioning.

[! ! Means for Solving the Problem] To achieve the above object, 1. In the focusing structure of the information reading device according to the present invention, a mirror pair is formed by arranging two reflecting mirrors with their reflecting surfaces facing each other at an angle of 90°. At least one set of optical path bending sections are interposed in the optical path from the information display surface to the camera section so as to be movable in a direction parallel to the optical path.

[Embodiment J of the Invention Next, an embodiment of the present invention will be described based on the accompanying drawings.

Figure 1 is mechanical sorting! In Fig. 0, which is a conceptual configuration diagram showing the focusing structure of the information reading section in the e-position, lO is a conveyor, 50 is a sorted object conveyed by the conveyor lO, and 20 is a camera. A portion 30 is a moving portion serving as an optical path bending portion.

The conveyed object 50 is conveyed by the conveyor conveyor 10.
A display sheet 51 displaying sorting information such as destinations pasted on the top surface is read by the camera unit 20 and an information processing unit (not shown) via the fixed mirror 6 and the movable mirror M30, and the automatic sorting device is controlled. Based on this read information, the conveyance section collects and sorts the conveyed articles 50 in different directions, depending on the destination and destination.

The conveyor 10 has m-end bells) 11 connected horizontally between rollers 12, and the endless bells) 11 are rotated by driving the rollers 12 by a driving means (not shown).
is designed to rotate. and,
The conveyed object 50 placed on the upper surface of the endless belt 11 is conveyed to water f in the direction indicated by the arrow in the figure.

A display sheet 51 is attached to the upper surface of the conveyed object 50 conveyed by the conveyor 10, on which sorting information such as destination is displayed, as described by Jtj.

The camera section 20 has a sensor 22 arranged at the image forming position of the lens 21, and the distance between the lens 21 and the sensor 22 is constant (ie, a fixed focus).

The sensor 22 has a line sensor composed of a CCD or the like arranged in a direction perpendicular to the moving direction of the image of the conveyed object 50 formed by the lens 21, and displays an information display section (on the display sheet 51) by the conveyance movement of the conveyed object 50. It may be configured to scan the display surface (surface), or it may be configured to read the display surface at once as an area sensor, which can be selected as appropriate depending on the application.

The camera section 20 has a lens 21 above the conveyor 10.
horizontally (i.e., the conveyance direction of the conveyed object 50 and the display sheet) 51
) and 11? It is fixedly arranged at a position corresponding to the upper mirror 32 of the movable mirror section 30 described above, and the display sheet 51 of the conveyed object 50 is displayed on the sensor 22 surface by the lens 21 as well as through the fixed mirror 6 and the movable mirror section 30 described later. It is designed to form an image.

The movable mirror section 30 has two mirrors 31-32 with their mirror surfaces 31A and 32B facing each other so that the angle formed between them is 9.
0°, and are fixedly arranged vertically and vertically on the jj7 moving frame 33 to form a pair of mirrors. Therefore, the light beam reflected by one mirror (31 or 32) and further reflected by the other mirror (32 or 31) exits in a direction parallel to and opposite to the direction of incidence.

The movable frame 33 is fitted into a guide rail horizontally fixed to the frame, chassis, bracket, etc. of the entire device (not shown) with a sliding diameter of 41I, and is fitted in the horizontal direction (El, the transport direction of the transported object 50). It is installed so as to be movable in a direction (direction parallel to the display sheet 51).

The fixed mirror 5-6 is fixedly arranged above a predetermined position of the transport compare 10 with its reflective surface 6A tilted downward by 45 inches from the vertical plane. It corresponds to the mirror 31 on the lower side of the mirror section 30. Therefore, when there is a display sheet) 51 of the transported object 50 below the fixed mirror 6, the image of the display sheet) 51 is displayed on the fixed mirror 6 and the moving mirror. The light is reflected by the lower mirror 31 of >-f130 and the upper mirror 32 of the movable mirror ff&30, and is incident on the camera unit 20.

Therefore, in the focusing structure of the information reading unit configured as described above, when the size (height in this case) of the conveyed object 50 differs and the distance from the display sheet 51 to the camera unit 29 changes. , by moving the movable mirror section 30 in the horizontal direction.
The image of the display screen 51 can be formed on the sensor 22 of the camera section 20 (so-called focusing) by keeping the distance to a constant value.

With this configuration, the optical path reciprocates between the fixed mirror 6 and the camera section 20 and the movable mirror fi30, so that the moving distance of the movable mirror section 30 required for focusing is reduced to the position W1 of the top surface of the conveyed object 50. For example, when the top surface position of the conveyed object 50 changes as shown by H in the figure (i.e., the height of the adjacent conveyed object If the difference is H),
The movement #fiL of the moving mirror section 30 is.

L=H/2 This is the result.

Furthermore, since the mirrors 31 and 32 of the movable mirror unit 30 are arranged opposite to each other with an included angle of 90'',
Even if the movable mirror section 30 as a whole is tilted, the incident optical path and the outgoing optical path are always parallel. Therefore, the movable mirror section 3
The zero movement structure requires high precision and is easy to manufacture.

The moving mirror fl130 is driven to move by controlling the optical path bending part 30 by a pulse motor or the like, and at the same time measuring the upper surface position of the conveyed object 30 above the conveyor lO! t, and automatically move and drive based on the measured value by the sound measuring device.Furthermore, since the lens 21 of the camera section 20 has a predetermined depth of focus, the operator can easily carry it. Even if the size (height) of the conveyed object 50 is visually measured and the object is moved manually, if the accuracy is within that depth, the distance is u.

In addition, in order to perform highly accurate and stable reading, a certain level of illuminance is required on the information display surface (display sheet) 21), but the absolute position of the information display surface (display sheet) 21) In the case shown in letter L where the lighting device goes up and down, if the lighting device is fixedly installed, the illuminance will not be constant because the distance between the lighting device 0 display sheet 21 will change.Therefore, the lighting section indicated by 40 in Fig. , display sheet) 21 and is interposed in the optical path from the camera section 20.

As described above, the illumination section 40 is located in the optical path from the display sheet 21 to the camera section 20 (mirror 32 on the upper side of the movable mirror section 30).
and camera unit 20), a half mirror 41 is interposed at an angle of 45'' with respect to the optical path, and a lamp 42 is fixedly arranged in front of the optical path bent by the half mirror 41. As a result, lap 42
The illumination light from the half mirror 41 - movable mirror section 30
The light reaches the display sheet 21 through the fixed mirror 6 and illuminates the display sheet 21h surface. With this configuration, the illumination optical path and the reading optical path coincide, and the above-mentioned moving mirror section 30
The distance from the lamp 42 to the display sheet 21 is always maintained constant by the focusing operation caused by the movement of the display sheet 21, and the illuminance on the surface of the display sheet 21 is always constant, allowing stable and highly accurate reading. .

FIG. 2 shows a second embodiment of the present invention. In FIG. 2, components having the same functions as those of the first embodiment are given the same reference numerals.

The difference between the second embodiment and the first embodiment is that the movable mirror section 30' has four mirrors 31'-32', 33' and 3'.
4' (two pairs of mirrors). #The movable mirror fi30 of the first embodiment is stacked in two stages, and the two central mirrors 3
An included angle of 90@ to connect the optical path facing 2'033'
It is constructed by fixedly arranging a pair of fixed mirrors 7 (mirrors 7A and 7B). With this configuration,
Moving mirror section 30', fixed mirror 6, and fixed mirror pair 7
The optical path makes two round trips between the two.

Therefore, the moving distance of the movable mirror section 30 is equal to 1/4 of the amount of change in the conveyed object 50's position a (display sheet 51).
(L=H/4) is a good thing.

In the above embodiment, the optical path is made horizontal by passing through the fixed mirror 6, and the movable mirror section 30 is configured to be movable horizontally, but the movable mirror f! 130 can be changed vertically.

Effects of the Invention As described above, according to the focusing structure of the information reading section according to the present invention, focusing can be performed without moving the camera section, which is sensitive to vibrations and shocks.

This makes it possible to increase the durability of the information reading section. In addition, it is possible to move at high speed, and the amount of movement of the optical path bending part for focusing is small, making it possible to increase the conveyance speed of conveyed items, making sorting work more efficient. .

[Brief explanation of the drawing]

FIG. 1 is a conceptual diagram of a first embodiment of the focusing structure of an information reading section according to the present invention in an automatic sorting device, and FIG. 2 is a conceptual diagram of a second embodiment thereof. lO... Conveyor (conveying means) ' 20... Camera section 30... Moving mirror section (light path bending section) 31, 32...
・Mirror (reflector) 50... Conveyed object (object) 31-32... Mirror (reflector) 50... Conveyed object (object) 51... Display sheet (information display surface) 1st figure

Claims (1)

[Claims] In an image reading device that uses a camera section to read the information display surface of an object that is moved by a conveying means, and where the distance between the camera section and the information display surface changes depending on the individual object, two An optical path bending section including at least one pair of mirrors configured by arranging reflecting mirrors with reflective surfaces facing each other at an angle of 90° is provided in the optical path from the information display surface to the camera section in a direction parallel to the optical path. A focusing structure for an information reading device, characterized in that it is configured to be movably interposed.