JPS6349705Y2 - - Google Patents

Description

[Detailed description of the invention] This invention is a water leak detection system equipped with a circuit to prevent malfunctions that does not immediately issue an alarm even if two electrodes are accidentally bridged by a conductor. Concerning vessels.

With conventional water leakage detectors, even if a human hand, metal, or mouse accidentally touches the space between the two detection electrodes, a water leakage alarm is immediately issued, and a supervisor is alerted each time. was bothering me.

Therefore, the present invention provides a water leakage detector that eliminates the above problems. Hereinafter, one embodiment of the present invention will be described based on the drawings.

In general, water leak detectors do not cause any problems even if the alarm is delayed by several seconds. This proposal was devised with attention to this actual situation,
FIG. 1 shows the circuit, and FIG. 2 shows a time chart of the output signal b with respect to the input signal a.

As shown in FIG. 1, the water leakage detector of the present invention has two detection electrodes 1 and 2 arranged in parallel and spaced apart on the water leakage detection surface, and both electrodes 1 and 2 are connected to each other via the excitation coil of the first relay R. Apply voltage between 2. Then, a timing relay T circuit is created via r, which is the a contact of the first relay R, thereby forming a constant time continuous input signal confirmation circuit 3. The timing relay T
has a delay time on the order of seconds, and uses a bellows type pneumatic relay or a thermal type relay having a bimetal. Note that a motor timer using a synchronous motor may be used instead of the timing relay T. Then, the delay time τ of the timing relay T is set to about several seconds. Next, t, which is the a contact of timing relay T.
A circuit of a second relay Q is formed through a self-holding contact q ₁ parallel to the self-holding contact q 1 , and an output circuit of the present detector is formed by q ₂ which is the a contact of the relay Q.

Next, the operation of the water leakage detector of the present invention will be explained.

First, if a mouse or a human hand accidentally touches the space between the detection electrodes 1 and 2, the input signal a
As a result, the first relay R is turned on, and the timing relay T is energized. However, since the delay time τ of the timing relay T is set to several seconds,
A water leak signal is not output immediately. During this time, a mouse may pass between the electrodes 1 and 2, or the hand that touched the electrode may be removed from the electrode, so that the input of signal a disappears, and the first relay R is turned OFF and the timing relay T is energized. The current is also turned off. Therefore, if the duration x of the input signal a is shorter than τ, the water leakage signal b is not output.
Next, when there is a bridge between both electrodes 1 and 2 due to water leakage,
The input signal a continues until the leakage stops and the bridge is dry. Generally, it takes at least minutes for the bridge to dry.
Therefore, the first relay R, timing relay T,
The second relays Q operate in sequence, the water leakage signal b is output, and an accurate water leakage alarm is issued.

As is clear from the above embodiments, the configuration of the detector of the present invention is such that when the two detection electrodes 1 and 2 are bridged due to water leakage, the water leakage detector outputs the water leakage signal b. When the electrodes 1 and 2 are bridged by a conductor, the input signal a continues for more than the time τ, which is sufficient to remove the bridge.
The system is equipped with a fixed-time continuous input signal confirmation circuit 3 which outputs a water leakage signal b only when the water leakage signal b is detected.

Since the present invention has the above-mentioned configuration, even if one's body etc. accidentally touches the detection electrode for a short time, the water leakage signal b will not be output and it will not bother the monitoring staff. It can be activated and output a water leakage signal.

[Brief explanation of the drawing]

Fig. 1 shows an electric circuit showing an embodiment of the water leakage detector of the present invention, and Fig. 2 shows its time chart. 1, 2...Detection electrode, 3...Continuous time input signal confirmation circuit, a...Input signal, b...Water leakage (output) signal, R, Q...Relay, T...Timing relay, r, t, q ₁ , q ₂ ...A contact, c...manual operation return contact, τ, x...time.

Claims (1)

[Scope of utility model registration request] In a water leakage detector that outputs a water leakage signal b when two detection electrodes 1 and 2 are bridged by water leakage, the bridge is detected when both electrodes 1 and 2 are mistakenly bridged by a conductor. For a time τ sufficient for removal,
A water leak detector comprising a fixed time continuous input signal confirmation circuit 3 which outputs a water leak signal b only in response to an input signal a that has been continued for a period of time τ or more.