JPH03235048A - Measuring apparatus for residual chlorine - Google Patents

Abstract

PURPOSE:To detect residual chlorine in water to be inspected by the use of a simple apparatus by housing the water to be inspected in a reservoir, making a concentration sensor face a vapor phase part in the reservoir and detecting the residual chlorine which has been vaporized from the water and has filled the vapor phase part. CONSTITUTION:A mark 3 is provided on a part which exhibits approximately 70% of capacity of a solution reservoir 1 provided with an opening 2 on an upper section, and an upper part from the mark 3 is a vapor phase part 4. A concentration sensor 6 comprising an ion sensitive film is attached on a position on the rear of a lid 5 and facing the vapor phase part 4. With the lid 5 removed, water W to be inspected, for example tap water, is put into the solution reservoir 1 up to the mark 3, and the opening 2 is closed by the lid 5. Then with a power switch ON, voltage is applied to a control circuit 7 and a driving circuit 8 to have a resistance value of the concentration sensor 6 varied as an electric signal. Since residual chlorine in the vapor phase part 4 is not stable in an initial state, a delay circuit is prepared in the driving circuit 8 and the driving circuit 8 makes an output to light up a display 9 when the residual chlorine becomes stable.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to a device for measuring residual chlorine contained in household tap water, public facility water, pool water, and the like.

(b) Conventional technology Sodium hypochlorite is added to household tap water and pool water for disinfection. However, this sodium hypochlorite has a strong odor, and when it is used as drinking water, a so-called water purifier that removes residual chlorine using activated carbon has been proposed, for example, as shown in JP-A-59-183883.

Now, for example, there are galvanic, polaro, and colorimetric measuring instruments used by health centers to detect residual chlorine in tap water or pool water for hygiene management reasons. The reliability is low and preparation is troublesome due to the use of reagents. Also, test water at 0.5 to 1 minute per minute.
3. There is a so-called electrode type that measures by turning on the flow, but it not only wastes the water sample but also requires a control device to maintain a constant flow rate, making it large and expensive.

(c) Problems to be Solved by the Invention The present invention detects residual chlorine in sample water using a simple device.

(d) Means for Solving the Problems The present invention provides a liquid storage tank that accommodates test water, a lid that closes an opening of the liquid storage tank, and a lid located at a position facing the gas phase of the liquid storage tank. It consists of an attached concentration sensor, a control circuit that changes an electrical signal based on the temperature detected by the concentration sensor, and a display that displays the output of the control circuit.

(e) The working test water is stored in a liquid storage tank, and a concentration sensor is placed facing the gas phase in the liquid storage tank to detect residual chlorine that has evaporated from the test water and filled the gas phase. Depending on the concentration of this residual chlorine, the indicator lights up or becomes an indicator based on the output of the control circuit.

(f) Example Embodiments of the present invention will be described based on the drawings.

(1) is a liquid storage tank with an opening (2) at the top, a mark (3) is provided at about 70% of the internal capacity, and the area above this mark is a gas phase part (4). (5) is a lid body that removably closes the opening (2) of the liquid storage tank (1);
6) is a concentration sensor made of an ion-sensitive membrane attached to the back side of the lid facing the gas phase part (4), and is used to detect the sample water (
The resistance value changes depending on the concentration of residual chlorine.

(7) is a control circuit that is connected to the concentration sensor (6) and changes an output electrical signal based on the concentration detected by the concentration sensor; (8) is a drive circuit that decodes the output of the control circuit; ) is a 7-segment, 3-digit display that digitally displays the concentration detected by the concentration sensor (6) based on the output of the drive circuit; (10) is the control circuit (7), the drive circuit (8), and the display; This is the power supply for operating the device (9).

Thus, the liquid storage tank (1), the lid body (5) having the concentration sensor (6), the control circuit (7), the drive circuit (8), and the indicator (9
) and the power source (10) are each housed in one case (not shown).

Next, regarding the measurement order, remove the lid (5) and sample tap water (W) at the mark (3) in the liquid storage tank (1).
) and close the opening (2) with the lid (5). Next, when the power switch (not shown) is turned on, a voltage is applied to the control circuit (7) and the drive circuit (8), changing the resistance value of the concentration sensor (6) as an electrical signal. Since the residual chlorine in the part (4) is not stable, a delay circuit (not shown) is installed in the drive circuit (8) in advance so that the residual chlorine in the drive circuit (8) is not stable.
) is output and the display (9) lights up.

Of course, it is also possible to enter a concentration value determined by a public health center or the like into the drive circuit (8) in advance and display it as an increase or decrease value compared to the concentration in the test water (W). The device may be a meter type that indicates by a pointer.

(G) Effects of the Invention As described above, the present invention detects residual chlorine in the gas phase using a concentration sensor, so the accuracy is significantly improved compared to a method in which the sensor is inserted into the sample water for detection. (If the sensor is placed in the test water, other impurities in the test water will adhere to the sensor and cause false detections.)Also, when measuring the test water, simply place the test water in the storage tank. It is easy to handle, and since no reagents are required, continuous use is possible. Furthermore, since the concentration sensor is attached to the back of the lid, the concentration sensor does not get in the way when cleaning the liquid storage tank, and since the concentration sensor is placed opposite the surface of the sample water, residual chlorine can be detected quickly. And it will be accurate.

[Brief explanation of drawings]

The drawing is a schematic explanatory diagram of a residual chlorine measuring device showing an embodiment of the present invention. (1)...Liquid storage tank, (2)...Opening, (4)...
・Gas phase part, (5)... Lid, (6)... Concentration sensor, (7)... Control circuit, (8)... Drive circuit, (9
)...Indicator, (W)...Water test.

Claims (2)

[Claims] (1) A liquid storage tank that accommodates sample water, a lid that closes the opening of the liquid storage tank, a concentration sensor attached to a position facing the gas phase of the liquid storage tank, and detection by the concentration sensor. A residual chlorine measuring device comprising a control circuit that changes an electrical signal based on concentration and a display that displays the output of the control circuit. (2) The residual chlorine measuring device according to claim 1, wherein the concentration sensor is attached to the back surface of the lid body and is opposed to the surface of the sample water.