JPH053580B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a processing liquid management device for determining the level position of various processing liquids in a storage tank and their degree of fatigue, and particularly for processing liquids such as developers in silver halide photography. This is suitable for application to automatic management.

<Conventional technology> In automatic processing equipment that automatically develops silver halide photographs, it goes without saying that the temperature of processing solutions such as developing solution and fixing solution must be controlled, as well as the amount of processing solution in the storage tank. It is also necessary to control the degree of fatigue, and the processing liquid must be replenished or replaced as appropriate.

In general, a known method for controlling the liquid level position is to electrically detect the liquid level position of the processing liquid using electrodes or float switches, and automatically control the amount of processing liquid based on this. Processing solutions such as developing solutions that are susceptible to chemical changes can cause corrosion of electrodes, generation of precipitates, or deterioration of quality, so control is usually performed using optical methods or visual inspection.

On the other hand, the degree of fatigue of the processing solution is determined based on the amount of processed material and the degree of discoloration of the processing solution visually observed by the operator.

<Problems to be Solved by the Invention> Conventionally, the degree of fatigue of a processing liquid due to chemical changes, etc. has only been determined based on intuition and experience, or using other expensive equipment. This is one of the obstacles in attempting to automate the process of replacing processing liquids.

Furthermore, in order to manage the liquid level of the processing liquid and the above-mentioned fatigue level, conventionally, each detection system had to be provided independently, which resulted in an expensive system.

Based on this knowledge, it is an object of the present invention to provide a low-cost processing liquid management device that can determine the level position and fatigue level of the processing liquid with a simple structure.

<Means for Solving the Problems> A processing liquid management device according to the present invention includes: a storage tank in which a processing liquid is stored; a light source that projects a certain amount of signal light obliquely onto a wall surface of the storage tank; a transparent window formed to guide light from the light source into the storage tank; and at least one light receiving element sandwiching the storage tank and facing the light source and for detecting the signal light, formed in the storage tank. a transparent window that guides the signal light passing through the processing liquid to the light receiving element when the liquid level of the processing liquid with respect to the storage tank of the lever is at least at a preset position; The apparatus includes a determining means for determining the level position and fatigue level of the processing liquid from the incidence of the signal light on the light receiving element and the amount of the signal light.

<Function> When the amount of processing liquid in the storage tank is small, the signal light from the light source deviates from the optical path to the light receiving element and hits the inner wall of the storage tank, but when the amount of processing liquid reaches a predetermined amount, the signal light enters the light-receiving element, the determining means determines that the surface position of the processing liquid with respect to the storage tank is at a preset position. At the same time, the degree of fatigue corresponding to the transparency of the processing liquid is determined from the amount of light incident on the light receiving element.

<Example> As shown in FIG. 1 showing the schematic structure of an example in which the processing liquid management device according to the present invention is incorporated into a developing processing system for silver halide photography, and FIG. 2 showing the planar shape of the main part thereof. Above the developer tank (storage tank) 12 that stores the developer 11, a reserve tank 13 is connected via a liquid supply pipe 15 having an on-off valve 14 in the middle, and a drain pipe 17 having an on-off valve 16 in the middle. is connected to the lower end of the developing tank 12.
The operation of these on-off valves 14 and 16 is controlled by a control device 18, and is operated based on a signal from a light receiving element, which will be described later. A light emitting diode (light source) 19 and a phototransistor (light receiving element) 20 face each other with the developing tank 12 in between.
This means that the signal light 21 from the light emitting diode 19 is parallel to the liquid level of the developer 11 and
The signal light 21 is fixed at a certain height relative to the developing tank 12 so that it enters the wall surface obliquely, and when the level of the developer 11 is higher than this, the signal light 21
is refracted at the boundary between the developer tank 12 and the developer 11 and is incident on the phototransistor 20. Therefore, a pair of transparent windows 22 are formed in the developing tank 12 to allow the signal light 21 to pass therethrough.

In this embodiment, the light emitting diode 19 was used as the light source, but the signal light 21 is characterized by always having a constant amount of light, a parallel light beam with a small cross-section with low diffusivity, especially in the infrared region that does not sensitize photosensitive materials. desirable. Also, instead of forming the window 22, the developing tank 1
It is also possible to make the entire wall 2 out of transparent material and have the entire wall function as a window.

When the amount of developer 11 in developer tank 12 is small, signal light 21 from light emitting diode 19 does not reach phototransistor 20 because it is not refracted enough to pass through the air. When there is no electrical signal from the phototransistor 20, the control device 18 opens the on-off valve 14 to supply the developer 1.
1 is supplied into the developing tank 12. developer 11
When the liquid level reaches the height of the light emitting diode 19, the signal light 21 is refracted by the developer 11 and enters the phototransistor 20. When the phototransistor 20 detects the signal light 21, the control device 1
8 immediately closes the on-off valve 14 to stop the supply of developer 11 from the preliminary tank 13 into the developing tank 12, and when the electric signal from the phototransistor 20 is no longer transmitted, opens the on-off valve 14 again. A control cycle in which the developer 11 is sent to the developer tank 12 is repeated. As a result, the level of the developer 11 in the developer tank 12 is always kept constant.

On the other hand, a control device 18 functioning as a determining means
is the magnitude of the electrical signal (for example, the amount of current) from the amount of light incident on the phototransistor 20 of the signal light 21.
is below a preset value, developer 1
1, the on-off valve 16 is kept open for a certain period of time, and the developer 11 in the developer tank 12 is discharged to the outside from the drain pipe 17. At this time, on-off valve 1
4 is closed and opened at the same time as the on-off valve 16 is closed, and new developer 11 is supplied from the reserve tank 13. Note that it is not necessary to constantly perform this determination of the fatigue level, but when performing this determination operation, the on-off valve 14
It is necessary to set the opening time to be long enough to ensure that the signal light 21 passes through the developer 11.

In this embodiment, the developer 11 has been described, but the present invention can be applied to any processing liquid that has a property that its transparency changes in response to fatigue signals. Further, in this embodiment, the signal light 21 is connected to the developer 1.
Light emitting diode 19 parallel to the liquid level of 1
However, as shown in FIG. 3 representing the concept of another embodiment of the present invention, the direction from the light source 3 to the surface of the processing liquid 2 stored in the storage tank 1 whose wall surface is entirely transparent is set. It is also possible to make the signal light 4 enter obliquely. In this embodiment, a pair of light receiving elements 5 and 6 are attached to the storage tank 1, and the liquid level of the processing liquid 2 is controlled so as to be always located between the highest liquid level H and the lowest liquid level L.

<Effects of the Invention> According to the present invention, by using at least one light-receiving element, the position of the processing liquid level and the degree of fatigue can be determined at the same time, and a highly reliable device can be provided despite its low cost. can get.

[Brief explanation of drawings]

FIG. 1 is a conceptual diagram of an embodiment in which a processing liquid management device according to the present invention is applied to a developing processing system for silver halide photography, FIG. 2 is a plan view of the developing tank, and FIG. 3 is a conceptual diagram of another embodiment of the present invention. It is a principle diagram of an example. Also, in the figure, 1 is a storage tank, 2 is a processing liquid, 3 is a light source, 4 and 21 are signal lights, 5 and 6 are light receiving elements, 1
1 is a developer, 12 is a developer tank, 14 and 16 are on-off valves, 18 is a control device, 19 is a light emitting diode,
20 is a phototransistor, and 22 is a window.

Claims (1)

[Claims] 1. A storage tank in which a processing liquid is stored, a light source that projects a certain amount of signal light obliquely onto the wall surface of this storage tank, and a transparent window formed in the storage tank that guides the light from the light source into the storage tank. , at least one light receiving element that faces the light source across the storage tank and detects the signal light, and is formed in the storage tank so that the level of the processing liquid with respect to the storage tank is at least at a preset position. In some cases, a transparent window is provided that guides the signal light that has passed through the processing liquid to the light receiving element, and is connected to the light receiving element so that the signal light is incident on the light receiving element and the amount of light is detected. A processing liquid management device comprising determination means for determining a liquid level position and a degree of fatigue.