JPH02102418A - Water level switch - Google Patents

Abstract

PURPOSE:To perform a sure operation without being blocked by floating dirt on the water surface by controlling an electric current which is supplied to a heat generating device by a fixed temperature controller formed so that it can adjust calorific value. CONSTITUTION:When a water surface A is positioned at a reference water level, air lies between a temperature detecting part 6 and a heat generating part 8. In the temperature detecting part 6, the temperature of the air which is warmed up by the supply of the suitable calorific value from the heat generating part 8 is detected. And when the water surface A rises and reaches the temperature detecting part 6 by being filled with sewage flowing in a tank 1 through an inflow tube 2, the temperature detecting part 6 is surrounded by the water. At this time, as the thermal conductivity of air is different from that of water, the calorific value for maintaining the temperature which surrounds the temperature detecting part 6 in a prescribed one increases and the electric current supplied to a heat generating device 7 by the fixed temperature controller 10 increases. Then, by detecting that the water surface reaches the prescribed water level based on the increase in the electric current, the operating part 9 is closed. Then, the water surface A falls when a pump 4 is operated, so that the operating part 9 opens.

Description

[Detailed description of the invention] Industrial applications The present invention relates to a water level switch.

BACKGROUND OF THE INVENTION Conventionally, various water level switches have been used in pumping stations of sewage treatment facilities. For example, there are electrode-type switches that detect changes in voltage and current between electrodes, float-type switches that operate using a float that moves up and down depending on the water level, ultrasonic switches, and capacitive mercury switches. Ta.

Problems to be Solved by the Invention However, according to the above-mentioned conventional configuration, debris floating on the water surface becomes tf! There was a problem in that the particles adhered to the floats and the switch and interfered with the operation of the switch.

The present invention is intended to solve the above-mentioned problems, and an object of the present invention is to provide a water level switch that can operate reliably without being hindered by debris floating on the water surface.

Means for Solving the Problems In order to solve the above problems, the present invention provides a temperature sensor in which the hot water part is located above the water surface of the reference water level, a heat generating device in which the heat generating part is located in the vicinity of the temperature sensor, and A constant temperature controller interposed in the connection circuit between the heat generating device and the power source and electrically connected to the temperature sensor, and a constant temperature controller located between the constant temperature controller and the temperature sensor in the middle of the connection circuit. the constant temperature controller controls the current supplied to the heat generating device so that the temperature detected by the temperature sensor becomes the set temperature;
The heat generating part is formed to be able to adjust the amount of heat generated, and the operating part is configured to:
The current value supplied to the heat generating device is detected, and the opening/closing operation is started based on this current value.

Effect With the above configuration, when the water surface is at the reference water level, the temperature sensing part is surrounded by air, and when the water level rises and reaches the temperature sensing part, the temperature sensing part is surrounded by water. Furthermore, since the thermal conductivity of air and water increases, and the thermal diffusivity of air is lower than that of water, the amount of heat required to maintain the area around the temperature sensing part at a predetermined temperature is This increases when the temperature-sensing part is located underwater, compared to when the temperature-sensing part is located underwater. For this reason, when the temperature sensing section is submerged from the air into water, the constant temperature controller increases the current supplied to the heat generating device in an attempt to maintain the temperature detected by the temperature sensing section at the set value. Then, the operating section detects that the water level has reached a predetermined water level by detecting the increase in the current, and performs an opening/closing operation. moreover,
When the operating section is opened or closed, the water supply system stops and the drainage system is activated.When the water level drops and the temperature sensing section is repositioned in the air, the amount of heat generated by the heat generating section is suppressed, the current decreases, and the operating section is opened and closed again based on the change in current value, and either the water supply system is activated or the drainage system is stopped.

EXAMPLE Hereinafter, an example of the present invention will be described based on the drawings. In FIG. 1, an inflow pipe 2 and an outflow pipe 3 are open inside a tank 1, and a pump 4 is interposed in the outflow pipe 3. Also, inside the tank 1, a temperature sensor 5 is installed at a temperature sensing section 6.
is disposed above the water surface at the reference water level, and furthermore, a heat generating device 7 is disposed with a heat generating section 8 located near the temperature sensing section 6 of the temperature sensor 5. And the heat generating device 11f7
is connected to the power supply 11 via the operating section 9 and the constant temperature controller 10.
A constant temperature controller 10 and a temperature sensor 5 are electrically connected. This constant temperature controller 10 controls the current supplied to the heat generating device 7 so that the temperature detected by the temperature sensor 5 becomes the set temperature.
The amount of heat generated by the heat generating section 8 is adjusted. Further, the actuating unit 9 detects the current value supplied to the heat generating device 7,
It is configured to close or open only when the current value exceeds a predetermined value. Further, the actuating section 9 is connected to the pump 4
electrically connected to.

Hereinafter, the effects of the above configuration will be explained.

When the water surface A is located at the reference water level, air is present between the temperature sensing section 6 and the heat generating section 8. The temperature sensing section 6 detects the temperature of the air warmed by the heating section 8, and the heating section 8 applies an appropriate amount of heat to the air so that the temperature sensing section 6 can detect a predetermined temperature. supply Then, when the water surface A rises due to the sewage flowing into the tank 1 from the inflow pipe 2 and reaches the temperature sensing section 6, the temperature sensing section 6 is surrounded by water. At this time, the thermal conductivity of air and water is different, and the thermal diffusivity of air is lower than that of water. The temperature increases when the temperature-sensing section 6 is located underwater than when it is located underwater. For this reason, when the temperature sensing section 6 is submerged from the air into water, the constant temperature controller increases the current supplied to the heat generating device in an attempt to maintain the temperature detected by the temperature sensing section at the set value. Then, by detecting the increase in the current, the operating section 9 detects that the water level has reached a predetermined water level and closes. Furthermore, the pump 4 is activated by closing the actuating part 9, and the water inside the tank 1 is transferred to the outside of the tank 1 through the outflow pipe 3. Then, when the temperature sensing part 6 is repositioned in the air due to a drop in the water surface A, the amount of heat generated by the heat generating part 8 is suppressed, the current decreases, and the operating part 9 is opened. In this embodiment, the pump 4 as a drainage device is controlled, but the operating section 9
The operation of the water supply device may be controlled by operating the operation in the opposite manner to that described above.

Effects of the Invention As described above, according to the present invention, by utilizing the difference in thermal conductivity between water and air and detecting changes in the current supplied to the heat generating device, it is possible to eliminate interference from dust, etc. It can operate by reliably detecting the water level without any problems.

[Brief explanation of the drawing]

FIG. 1 is an overall configuration diagram showing an example of a cotton sewage according to the present invention. 5... Temperature sensor, 6... Temperature sensing part, 7... Heat generating device, 8... Heat generating part, 9... Operating part, 10... Constant temperature controller, 11... Power supply. Agent Yoshihiro Morimoto 1st

Claims (1)

[Claims] 1. A temperature sensor whose temperature sensing part is located above the water surface at a reference water level, a heat generating device whose heat generating part is located near the temperature sensor, and a connecting circuit between the heat generating device and a power source, The constant temperature controller includes a constant temperature controller electrically connected to the temperature sensor, and an operating section located between the constant temperature controller and the temperature sensor and interposed in the middle of the connection circuit, and the constant temperature controller is configured to generate heat. The heating unit is configured to be able to adjust the amount of heat generated by the heat generating unit so that the temperature detected by the temperature sensor becomes the set temperature by controlling the current supplied to the device, and the actuating unit detects the value of the current supplied to the heat generating unit. , a water level switch characterized in that the opening/closing operation is activated based on this current value.