JPH01159097A - Sterilizing device for electric pump - Google Patents

Abstract

PURPOSE:To inject a chemical liquid corresponding to the change of a flow rate in a constant pressure pump, by controlling a chemical liquid injection apparatus so as to reduce the injected amount of the chemical liquid in response to the return of a pressure switch from a closed state to an open state. CONSTITUTION:This sterilizing device is adapted to an electric pump having a pressure switch 1, which shows a closed state when the pressure in a pipe is lowered to start an electromotor and returns to an open state by the rising in the internal pressure of the pipe, and a flow rate detector 2 for stopping the aforementioned electromotor when the flow rate in the pipe becomes lower than a predetermined flow rate. That is, in a chemical liquid injection apparatus 4, a sterilizing chemical liquid is injected into the water pumped up by the above-mentioned pump and a control means consisting of an AND circuit 5, an oscillator 3, an on circuit 9, a gate circuit 8 and a triac 6 controls the apparatus 4 so as to reduce the injected amount of the chemical liquid in response to the return of the pressure switch 1 from the closed state to the open state.

Description

DETAILED DESCRIPTION OF THE INVENTION FIELD OF INDUSTRIAL APPLICATION The present invention relates to a sterilizer for an electric pump that is added to a domestic electric well pump or the like.

Conventional technology Conventionally, the control of the sterilizer attached to an electric well pump was linked to the operation of the pump motor, and while the electric well pump was in operation, the sterilizer was operated continuously to inject chemicals. Subsequently, when the electric well pump stopped, the sterilizer also stopped.

Problems to be Solved by the Invention However, with this configuration, there is no major problem when used in an electric well pump that starts and stops only with a pressure switch, but it starts with a pressure switch and stops with a flow rate switch. Constant pressure type electric well pumps were inconvenient. This is because the amount of chemical solution injected per unit time into the sterilizer is constant, so when the sterilizer is about to stop, that is, the flow rate is very small. On the other hand, if the injection amount is adjusted to reach a drinkable concentration at a low flow rate,
This time, when the flow rate was very high, the concentration of the chemical solution decreased too much, making it impossible to sterilize.

The present invention has been made in view of these conventional problems, and it is an object of the present invention to provide a sterilizer for an electric pump that is capable of injecting a chemical solution in response to changes in flow rate in a constant pressure pump.

Means for Solving the Problems In a constant pressure pump, when the pressure inside the pipe falls below a predetermined value, the pressure switch is turned on and the constant pressure pump starts operating.

Then, the pressure of the pressure switch itself increases due to the operation of the pump (and returns from ON to OFF), so during operation, the pressure switch itself is in both the ON state and OFF state.

The present invention focuses on the fact that the flow rate also decreases when the pressure switch is turned OFF, and is configured to reduce the amount of chemical solution injected in response to the pressure switch returning to the OFF state.

Operation With the above configuration, the pressure switch can be used as a type of flow rate sensor, and when the flow rate is decreasing, the amount of chemical solution to be injected can be reduced.

Embodiment FIG. 1 shows a circuit configuration of a seedling reducer for an electric pump in an embodiment of the present invention. 1 and 2 are a pressure switch and a flow rate switch, respectively; 3 is an oscillator for causing the chemical injector 4 to operate intermittently; 5 is an oscillator 3 which receives an inverted signal of the output signal of the pressure switch 1 and an output signal of the flow rate switch 2; This is an AND circuit that sends an operation signal to the 6 is a triac for controlling the operation of the liquid injector 4; 7 is a power supply; 8 is a gate circuit for controlling the triac 6; 9 is a gate circuit that receives the output signal of the pressure switch 1 and the output signal of the oscillator 3; This is an OR circuit that sends an operation signal to 8.

The operation will be explained below. In Figure 2, pressure switch 1
When is ON, the output of the OR circuit 9 maintains a Hi level state, the gate circuit 8 continuously makes the triac 6 conductive, and the chemical liquid injector continuously operates. Pressure switch 1 is OFF and flow rate switch 2 is OFF.
When it is N, the output of the AND circuit 5 becomes Hi, the oscillator 3 operates accordingly, and the output of the OR circuit 9 becomes Hi and L.
Ow is repeated, and an intermittent signal is input to the gate circuit 8, and the chemical injector 4 performs intermittent operation.

Then, both the pressure switch 1 and the flow rate switch 2 are set to O.
The operation of the chemical liquid injector 4 is completely stopped only when it becomes FF.

In this embodiment, as shown in FIG. 2, while the electric pump is in operation, the chemical liquid injector 4 performs continuous injection until the pressure switch 1 is turned on, and when the pressure switch 1 is turned off. After that, the drug solution injector 4 performs intermittent injection, so that the amount of drug solution injected in the second half of the operating period of the electric pump can be reduced compared to the first half.

In this embodiment, the switch to intermittent injection of the chemical solution is configured as soon as the pressure switch 1 is turned off. However, if it is desirable to delay the start of the intermittent injection of the chemical solution, it is possible to switch from the time when the pressure switch 1 is turned off. A delay means may be provided to delay switching to intermittent injection for a predetermined period of time.

Effects of the Invention As described above, in the case of a constant pressure pump, only the pressure switch returns to the original O during operation as the pressure increases after the start of operation.
Focusing on returning to the FF state, the pressure switch is turned OFF.
By configuring the system to reduce the amount of chemical solution injected in response to the condition being restored, the amount of chemical solution injected will be reduced when the flow rate is extremely low after the pressure switch is turned off. There is no need to install a flow rate sensor just for injecting chemical liquid (with a very simple configuration, it is possible to change the amount of liquid injected according to the flow rate, and it is possible to use a constant pressure type electric pump. Even when added, the concentration of the chemical solution can be kept constant and water with an appropriate concentration can always be obtained.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram of an electric pump sterilizer according to an embodiment of the present invention, and FIG. 2 is a timing chart of each signal during operation of the electric pump sterilizer. l...Pressure switch 2...Flow rate switch 3
...Oscillator 4...Drug injection device 5.
...AND circuit 6...Triac 7...
...Power supply 8...Gate circuit 9...
Name of OR circuit agent: Patent attorney Toshio Nakao and one other person 1-m-pressure switch 6-m-triax Figure 2 N Renten of chemical liquid injector d

Claims (1)

[Claims] A pressure switch that closes the circuit when the pressure in the pipe drops below a predetermined pressure and starts the electric motor, and returns to the open circuit state when the pressure in the pipe increases, and stops the motor when the flow rate in the pipe drops below a predetermined flow rate. It is applied to an electric pump having a flow rate detector, and has a chemical liquid injection device for injecting a sterilizing chemical liquid into the water pumped by the electric pump, and the pressure switch returns from a closed state to an open state. A sterilizer for an electric pump, characterized in that a control means is provided for controlling the chemical liquid injection device so as to reduce the amount of chemical liquid injected in response to the above.