JPH0410520Y2 - - Google Patents

Description

[Detailed description of the invention] (Field of industrial application) The invention automatically opens a relief valve used in, for example, an electric water heater, and removes scale, dirt, etc. attached to the valve structure. This invention relates to an automatic valve opening device for a relief valve.

(Prior art) This type of relief valve is installed in electric water heaters, boilers, etc., and releases expanded water during heating almost evenly during the heating time, thereby keeping the internal pressure constant to prevent excessive pressure. It is used to hold the For this reason, the conventional relief valve structure has been provided with a valve opening mechanism that can be manually operated with respect to a valve body structure that discharges expanded water from a minute gap. The reason for this is that scale, dirt, etc. tend to get caught between the valve body and the valve seat during normal operation to allow expanded water to escape from the microgap. A valve is installed so that scale, dirt, etc. can be washed away. In addition, there is a risk that scale may gradually accumulate on the valve body, causing the valve to lock and become unable to open, so the valve opening mechanism should be manually operated at least once or twice a month to remove any stuck scale. It is necessary.

(Problems to be solved by the invention) However, in the case of forced opening by manual operation as described above, it is easy to forget to operate it, and this type of relief valve is located directly above the can body. Since they are often installed in high places, they are difficult to operate, and this poses a problem in terms of reliable operation.

Therefore, the applicant of the present invention previously proposed a relief valve to improve these drawbacks in Utility Application No. 77649/1983.
This relief valve is equipped with an electromagnetic valve opening device that can operate a solenoid to open the valve in response to an external electrical signal so that it can be operated remotely as well as manually.

However, even in this case, it is insufficient to provide an electric signal by manually operating a switch or the like.

Therefore, in order to improve the above-mentioned problems, the present invention aims to provide an automatic valve opening device that automatically opens an electromagnetic relief valve.

(Means to solve the problem) The gist of this invention is to attach a solenoid that forcibly opens the relief valve, and turn on the heater such as an electric water heater.
- When the OFF switch is activated, the solenoid is energized for a short time to automatically open and close the relief valve.

(Example) An example of the present invention will be described below based on the drawings. Figure 1 shows a block diagram of the entire device. When the power to an electric water heater (not shown) is turned on, relay coil 1 is energized and relay switch 2 closes, and when the power is turned off, relay switch 2 opens. .

When the relay switch 2 opens and closes, the pulse generator 3 generates pulses as shown in FIG. 2A, which are input to the monostable multivibrator 4 and trigger circuit 5, respectively. Monostable multivibrator 4
From there, a pulse B of a predetermined time T is outputted to the gate circuit 6 and the oscillation circuit 7, respectively. Further, the trigger circuit 5 outputs the waveform C triggered by the rise of the waveform A to the oscillation circuit 7, and the oscillation circuit 7 outputs the waveform D to the gate circuit 6 in response to the trigger waveform C. The gate circuit 6 inputs the waveform D of the oscillation circuit 7 to the next stage solid state relay 8 as shown in FIG. 2E until the waveform B falls after a predetermined time T. Upon receiving this, the solid state relay 8 applies 100V AC to the solenoid 9 of the electromagnetic relief valve by repeatedly turning ON and OFF.
The solenoid 9 operates an electromagnetic relief valve to be described later.

The electromagnetic relief valve that is opened and closed by a solenoid is shown in FIG. 3 or 4.

First, in the first embodiment shown in FIG. 3, when the solenoid 9 is energized, a magnetic body 10 directly connected to the valve shaft and the valve body is actuated to forcibly open the valve. First, a movable valve seat 31 is supported by a first biasing means 32 made of a coil spring with respect to a fixed valve seat 30, and is movably attached by a diaphragm 33, and a second biasing means 34 made of a coil spring is supported by a movable valve seat 31. A valve body 36 is attached to a valve shaft 35 that is supported by a valve shaft 35 in close contact with the movable valve seat 31.
Normally, when fluid pressure exceeding a predetermined value flows in from the inlet 37, the movable valve seat 31 moves to the fixed valve seat 30.
This is a relief valve structure in which the valve shaft 35 comes into contact with the stopper 38 and also separates from the valve element 36, thereby opening the valve. When the solenoid 9 is energized, the magnetic body 10 is attracted, and the valve shaft 35 and the valve body 36 directly connected to the magnetic body 10 are
The valve is forcibly pulled away from the fixed valve seat 30 against the biasing means 34 to open the valve.

Next, in the second embodiment shown in FIG. 4, when the solenoid 9 is energized, the magnetic body 10 presses the push pin to forcibly open the valve.

First, a movable valve seat 41 is supported by a first biasing means 44 made of a coil spring with respect to a fixed valve seat 40, and is movably attached by a diaphragm 43. A valve body 46 is attached to a valve shaft 45 that is supported so as to be in close contact with the movable valve seat 41. Normally, when fluid pressure exceeding a predetermined value flows in from the inlet 47, the movable valve seat 41 closes. The relief valve has a structure in which it separates from the fixed valve seat 40 and comes into contact with a push pin 49 supported by a third biasing means 48 made of a coil spring, thereby separating from the valve body 45 and opening the valve. When the solenoid 9 is energized, the magnetic body 10 is attracted and presses the push pin 49, and the push pin 49 contacts the valve shaft 45 and resists the second biasing means 42 to fix the valve body 46 to the valve seat. 40 forcibly to open the valve.

In the above embodiment, the time T during which the pulse B is generated by the monostable multivibrator 4 is
can be set arbitrarily, thereby making it possible to vary the number of times of opening and closing.

Further, the opening/closing operation described above can be performed only when the heater of the electric water heater is switched from OFF to ON or from ON to OFF.

(Effect of the invention) In electric water heaters, the heater power is turned on at least once a day if even a small amount of hot water is used.
Therefore, the relief valve can be automatically forced open once a day without manual operation, and scale and dirt can be cleaned each time, as well as preventing the valve from becoming inoperable due to sticking. It can be prevented.

Since the valve opening can be performed multiple times depending on the settings, it is possible to remove scale that is hard to remove by opening the valve only once, and also prevent secondary complaints such as dirt buildup.

In particular, the forced opening operation when the heater is switched from OFF to ON has the effect of eliminating the sticking of the valve and warming it up before normal operation.

In addition, the forced valve opening operation when the heater is switched from ON to OFF has the effect of immediately removing scale, etc. that has just adhered to the tank, preventing accumulation, and discharging gas generated inside the can.

Therefore, it is most effective to use both in combination, but it is also possible to switch only from OFF to ON or from ON to OFF.

[Brief explanation of the drawing]

The drawings all show embodiments of the present invention; Fig. 1 is a block diagram of the entire device, Fig. 2 is a waveform diagram of each part in Fig. 1, and Figs. 3 and 4 explain the structure of the electromagnetic relief valve. FIG.

Claims (1)

[Scope of utility model registration request] When the heater circuit of an electric water heater, etc. is switched from OFF to ON or from ON to OFF, a control pulse is generated, and the control pulse causes the electric water heater to An automatic valve opening device for a relief valve, characterized in that a relief valve installed in a vehicle, etc. is controlled to automatically open and close temporarily.