Patent ID: 12235147

MODE FOR INVENTION

Hereinafter, a configuration and an operation of a water level detection apparatus according to the present invention will be described with reference to the accompanying drawings, and a water level detection method in the apparatus will be described in detail.

FIG.1is a diagram illustrating a configuration of a water level detection apparatus according to the present invention andFIG.2illustrates a circuit diagram of the water level detection apparatus according to the present invention.

Referring toFIGS.1and2, the water level detection apparatus according to the present invention includes a micom10, a control signal output unit20, a conversion unit30, a water level detection unit40, and a water level signal input unit50.

The micom10outputs a first low water level control signal and a second low water level control signal which are square waves having a frequency when a water level monitoring event occurs, and have opposite phases to the control signal output unit20.

The micom10may also be configured to output the first low water level control signal and the second low water level control signal only for a predetermined time after the water level monitoring event occurs.

Further, the micom10adjusts the frequency of the water level monitoring signal output to the water level sensor (not illustrated), i.e., the water level ball in the water level detection unit40by adjusting the frequencies of the first low water level control signal and the second low water level control signal.

The micom10receives the water level monitoring signals for the first low water level control signal and the second low water level control signal from the water level signal input unit50, and performs a response operation. The response operation will be able to be changed according to a type constituting the water level detection apparatus. In the case of the boiler, for example, the micom10may generate a low water level warning, or generate a warning after forcibly ending the operation if the boiler performs operations such as heating, hot water, etc.

The control signal output unit20receives the first low water level control signal and the second low water level control signal, and outputs plus DC power and minus DC power having opposite phases for each of the first low water level control signal and the second low water level control signal to the primary side of the conversion unit30.

As illustrated inFIG.2, the control signal output unit20includes a first switching unit21, a second switching unit22, and a phase alternate DC voltage supply unit23.

The first switching unit21adopts a transistor inFIG.2, but may adopt other elements such as a relay, a MOS transistor, etc.

In the first switching unit21, an output terminal, i.e., a collector is connected to a primary plus terminal of the conversion unit30, and the first switching unit21receives the first low water level monitoring signal to be turned on or ff.

In the second switching unit22, the output terminal is connected to a primary minus terminal of the conversion unit30, and the second switching unit22receives the second low water level monitoring signal to be turned on or off, and is turned on when the first switching unit21is turned off and turned off when the first switching unit21is turned on.

One side of the phase alternate DC voltage supply unit23is connected to the output terminal of the first switching unit21and the other side is connected to the output terminal of the second switching unit22, and in order to alternately supply the plus DC power and the minus DC power to the primary side of the conversion unit30, the DC voltage is connected between the one side and the other side, and then connected to a primary intermediate point of the transformer30to alternately supply DC powers having different phases by turning on the first switching unit21and the second switching unit22to the intermediate point of the transformer.

The phase alternate DC voltage supply unit23may be configured to include a first diode D1 in which an anode is connected to the output terminal of the first switching unit and a cathode is connected to the intermediate point, a second diode D2 in which the anode is connected to the output terminal of the second switching unit and the cathode is connected to the intermediate point, and a third resistor R3in which the DC power is applied to one terminal and the other terminal is connected to the cathodes of the first diode and the second diode.

In the conversion unit30as a transformer including a primary side and a secondary side, when the output terminal of the first switching unit21is connected to the primary plus terminal (minus terminal) and the output terminal of the second switching unit22is connected to the primary minus terminal (plus terminal), the DC power (VCC) is connected to the primary intermediate point to generate the water level monitoring signal converted into the AC power for the DC voltage applied to the intermediate point and the plus terminal, and the intermediate point and the minus terminal and output the generated water level monitoring signal to the water level detection unit40.

The water level detection unit40supplies the water level monitoring signal to the water level sensor (not illustrated), i.e., the water level ball, and outputs the water level detection signal to the water level signal input unit50when detecting a low water level of a predetermined reference or less.

It will be preferable that the water level detection unit40applies a photo coupler PC1 in order to transfer the water level detection signal to the water level signal input unit50. To this end, a light emitting unit of the photo coupler PC1 should be configured in the water level detection unit40and a light receiving unit should be configured in the water level signal input unit50.

The water level signal input unit50receives the water level detection signal and processes the water level detection signal as a signal which may be recognized by the micom10and outputs the signal to the micom10.

Meanwhile, it will be able to be easily appreciated by those skilled in the art that the present invention is not limited only to the above-described preferred embodiment, but can be implemented by various modifications, changes, substitutions, or additions within the scope without departing from the spirit of the present invention. If the implementation by the modifications, changes, substitutions, or additions belongs to the category of the appended claims, it should be regarded that the technical spirit also pertains to the present invention.

EXPLANATION OF REFERENCE NUMERALS

10: Micom20: Control signal output unit30: Conversion unit40: Water level detection unit50: Water level signal input unit