JPH0136265Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to a switch that operates when there is a water flow in a water circuit, a so-called water flow switch, and particularly a type that operates only when the water supply temperature in the water circuit is below a certain temperature. This water flow switch can be used as a water heater control switch in a hot water system that combines a solar water heater and a water heater.

The conventional water flow switch of this type is as shown in Figure 1.
A cylindrical body 2 is provided in a main body 1 inserted into a water circuit, a reed switch 3 is housed in the cylindrical body, and a float 6 biased in the descending direction by a spring 4 is loosely fitted into the cylindrical body so as to be freely raised and lowered. , this float 6 is provided with a permanent magnet 7.

In the conventional device described above, when there is a flow of water from the inlet 11 to the outlet 12 of the main body 1, the float 6 is lifted up against the spring 4 by this water flow, and the permanent magnet 7 is attached to the contact part of the reed switch 3. The reed switch 3 is closed.

Using the water flow switch described above, it becomes possible to control the water heater in a water heating system that has a path from the solar water heater to the water heater to the faucet.

In other words, if the water flow switch is inserted into the hot water supply circuit leading from the solar water heater to the water heater, and the water heater is turned on by turning on the water flow switch, the water heater will automatically turn on when hot water is used. is activated to compensate for the lack of heating from the solar water heater.

However, when the water heater is activated when the solar water heater is sufficiently heated, the hot water coming out of the faucet becomes abnormally high, so a separate high-cut switch and sensor are required.

The present invention provides: from an inlet 11 to an outlet 12 in the main body 1.
A reed switch 3 is arranged in this flow path so that its axis coincides with the flow path axis, and this reed switch 3 is surrounded by a non-magnetic material. Float 6 loosely fitted on the body
is biased toward the upstream side, and the biasing force is set to a value such that the float 6 is moved downstream when a water flow occurs in the main body 1, and a permanent In the water flow switch in which the contact state of the reed switch 3 is changed by the magnet 7, the object to be controlled can also be controlled by the temperature of the water flow within the main body 1, and the control operation is reliable. In order to do this, under conditions where the water flow inside the main body 1 is higher than the set temperature, even if the water flow occurs, the reed switch 3
The task is to prevent this from becoming operational.

The technical means of the present invention for solving the above problem is as follows: A permanent magnet 7 provided in the reed switch 3
The arrangement position of the permanent magnet is set at a position away from the contact part of the reed switch 3 on the upstream side in an operating state in which a water flow is generated in the main body 1 and the float 6 is moved downstream from the initial position. In the operating state in which the float 6 is moved downstream by connecting the temperature-sensitive ferrite 71 closely attached to the permanent magnet 7 and provided on the float 6 in the downstream direction of the flow path with respect to the permanent magnet 7. The temperature-sensitive ferrite 7
1 is located on the outer periphery of the contact portion of the reed switch 3, and the temperature-sensitive ferrite 71 is made of a ferrite having a property that its magnetic permeability rapidly decreases when the temperature of the water stream rises above the set temperature. .

The above configuration of the present invention operates as follows.

When the water temperature in the flow path in the main body 1 is lower than the set temperature of the temperature-sensitive ferrite 71, the temperature-sensitive ferrite 71 has characteristics as a magnetic material with sufficient magnetic permeability. Therefore, the magnetic field lines of the permanent magnet 7 reach this temperature-sensitive ferrite 71, and when the float 6 is moved downstream by the water flow (operating state), the magnetic field through the temperature-sensitive ferrite 71 causes Then the contact state of reed switch 3 changes,
The water flow switch becomes operational. That is, it functions similarly to a conventional water flow switch.

Next, when the water temperature rises and reaches the set temperature of the temperature-sensitive ferrite 71, the magnetic permeability of the temperature-sensitive ferrite 71 rapidly decreases. Therefore, permanent magnet 7
The magnetic field from the reed switch 3 does not reach the temperature-sensitive ferrite 71, and the contact state of the reed switch 3 does not change even if the float 6 is activated as described above.

Since the present invention has the above configuration, it has the following unique effects.

Since the water flow switch itself is temperature-sensitive, the temperature of the supplied hot water can be changed, such as when trying to supply hot water at a predetermined temperature by reheating the hot water supplied from a solar water heater according to the set temperature of this hot water. In a reheating system where the temperature is not constant, there is no need to prepare a separate temperature sensing device. That is, in a reheating system in which reheating progresses according to the output when water flow is detected by a water flow switch, simply by inserting the temperature-sensitive water flow switch of the present invention into the reheating control circuit, the reheating device can supply hot water to the reheating system. It operates according to the temperature.

Further, in principle, since the conventional water flow switch is simply equipped with a temperature-sensitive ferrite, the water flow switch does not become extremely large.

Incidentally, Japanese Utility Model Application Publication No. 51-9761 also discloses a water level detection type switch consisting of a combination of a reed switch, a permanent magnet, and a temperature-sensitive ferrite, which is almost the same as the water flow switch of the present invention. If this device is used as a sensor similar to the water flow switch of the present invention, it will not function adequately. This is because the water level in the chamber containing the float (a chamber sealed from the atmosphere) does not change sufficiently depending on the presence or absence of water flow, and for this reason, water flow cannot be reliably detected. . The water flow switch of the present invention having the above configuration does not cause such inconvenience. Furthermore, when the prior art described above is associated with a hot water supply circuit, the temperature-sensitive ferrite located in the cavity housing the float does not come into sufficient contact with the supplied hot water, and in this respect, Although the temperature operation becomes uncertain, in the above structure of the present invention, the temperature-sensitive ferrite 71 is reliably surrounded by the supplied hot water, and the response operation is reliable.

Embodiments of the present invention will be described below with reference to FIGS. 2 and 3.

This water flow switch is incorporated, for example, in a solar water hot water supply system that reheats water or hot water from a hot water storage tank 9 as shown in FIG.

In this system, water stored in a hot water storage tank 9 is circulated and heated by a solar heat absorption device 91 installed on the roof, and the hot water in the hot water storage tank 9 is passed through a water heater 8 to a hot water supply circuit 80. It is now being supplied to

The combination of the hot water storage tank 9 and the solar heat absorption device 91 has a known configuration, and the water stored in the hot water storage tank 9 supplied from the water supply circuit 90 via the ball tap 92 is connected between the solar heat absorption device 91 and the hot water storage tank 9. It is configured to naturally circulate, which allows
This is a configuration in which the water stored in the hot water storage tank 9 is heated.

Next, the hot water supply circuit from the hot water storage tank 9 is directly connected to the water heater 8, and the water flow switch of the present invention is inserted downstream of the inlet 81 of this circuit on the upstream side of the heat exchanger 82. . And this entrance 81
is connected to the inlet 11 of the water flow switch shown in FIG. Electrically, the reed switch 3 of this water flow switch is incorporated into the hot water supply control device 83 of the water heater 8, and in this embodiment, the contact 31 of the reed switch 3 is set to be normally open. , the water heater 8 is configured to be in operation when the contact is closed.

On the other hand, the outlet 12 of the water flow switch is connected to a hot water supply circuit 80 via a heat exchanger in the water heater 8, and hot water reheated to a predetermined temperature or higher by the water heater 8 is supplied from the hot water supply circuit 80. It is supplied to kitchens, bathrooms, etc.

Therefore, in the above system in which the water heater 8 equipped with the hot water supply control device 83 incorporating the water flow switch shown in FIG. is controlled, and when the faucet is opened at each hot water supply location and a water flow is generated in the flow path in the main body 1 of the water flow switch,
The contact 31 of the reed switch 3 is closed, and the water heater 8 is put into operation by the output of the hot water supply control device 83. When the hot water supplied from the hot water storage tank 9 is at a temperature higher than the set temperature, the contact 31 of the reed switch 3 is not closed even if the float 6 is activated due to the above-described action, and the water heater 8 is not closed. The hot water storage tank 9 will not be operated, and hot water from the hot water storage tank 9 will be directly supplied to each hot water supply location via the hot water supply circuit 80.

Next, the water flow switch associated with the hot water supply control device 83 of the water heater 8 incorporated in the above system will be described in detail based on FIG. 3.

In this water flow switch, a sealed cylindrical cavity 30 is projected from the top wall of the cavity on the outlet 12 side formed in the main body 1 toward the inlet 11 side, and is fitted onto the top wall of the cavity on the outlet 12 side. A large-diameter body is formed on the proximal end side of the closed float 6, and a spring 14 is interposed between the large-diameter body and the top wall of the cavity to bias the float 6 toward the upstream side. This configuration is basically the same as that of the conventional example described above. A reed switch 3 which is incorporated into the hot water supply control device 83 and has a contact point 31 is installed in the empty chamber 30, and the contact point 31 is located in the middle of the empty chamber 30. There is.

Next, the fixed permanent magnet 10, the permanent magnet 7, and the temperature-sensitive ferrite 71 are all formed in an annular or cylindrical shape. are laminated on. Here, the length of the temperature-sensitive ferrite 71 in the axial direction is set to be sufficiently long, and the fixed position of the fixed permanent magnet 10 is set to the reed switch 3.
The temperature-sensitive ferrite 71 is positioned sufficiently away from the contact 31 of the reed switch 3 so that the center portion of the temperature-sensitive ferrite 71 coincides with the contact 31 of the reed switch 3 when the float 6 is in operation. In addition, when the float 6 is in operation, the downstream end surface of the temperature-sensitive ferrite 71 is connected to the fixed permanent magnet 1.
0, the depth of the float 6 having a top closed shape is set to a predetermined dimension, and the current direction of the fixed permanent magnet 10 and the direction of the magnetic pole of the permanent magnet 7 are set so that the float 6 and the empty chamber 30 are in contact with each other. are set in the same direction with respect to the axis of

Therefore, in this embodiment, when a water flow is generated in the main body 1 and the float 6 is in the operating state, as described in the section of the above-mentioned operation, if the temperature of the inflow water from the inlet 11 is low, The contact 31 switches from the open state to the closed state, but if the inflow water temperature is higher than the set temperature, the magnetic permeability of the temperature-sensitive ferrite 71 is extremely reduced, and the magnetic flux of each permanent magnet is does not include the contact 31 of the reed switch 3, and the contact 31 will not be in the closed state.

In this action, when the inflow water temperature is lower than the set temperature, the magnetic field of the permanent magnet 7 reaches the temperature-sensitive ferrite 71, and the combination of the permanent magnet 7 and the temperature-sensitive ferrite 71 becomes an integrated magnet. This will act on the reed switch 3 as a result. Due to this action, the contact 31 is closed when the float 6 is in operation. In this embodiment, when the float 6 is in operation, the temperature-sensitive ferrite 71 is attached to the permanent magnet 7. The structure is such that the magnetic field of the fixed permanent magnet 10 and the magnetic field of the fixed permanent magnet 10 act together. Therefore, compared to a structure having only one permanent magnet 7, even if the permanent magnet 7 on the float 6 side is made smaller, sufficient magnetic flux is generated in the temperature-sensitive ferrite 71. That is, the responsiveness to the water flow of the float 6 is improved.

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram of a conventional example, Fig. 2 is an explanatory diagram of a system using an embodiment of the present invention, and Fig. 3 is a sectional view of an embodiment of the present invention. ...Float, 7...
...Permanent magnet, 10...Fixed permanent magnet, 71...Soft ferrite.

Claims (1)

[Scope of utility model registration request] A flow path from an inlet 11 to an outlet 12 is formed in the main body 1, and a reed switch 3 is disposed within this flow path so that its axis coincides with the flow path axis. Surround yourself with your body;
While urging the float 6, which is loosely fitted into the enclosure and equipped with a permanent magnet 7, toward the upstream side,
The biasing force is set to such a value that the float 6 is moved downstream when a water flow is generated in the main body 1, and the contact point of the reed switch 3 is set by a permanent magnet 7 provided on the float 6. In a water flow switch that can switch states, the permanent magnet 7 provided in the reed switch 3 is arranged in an operating state in which a water flow is generated in the main body 1 and the float 6 is moved downstream from the initial position. The temperature-sensitive ferrite 71 is set at a position away from the contact part of the reed switch 3 on the upstream side, and is in close contact with the permanent magnet 7 and provided on the float 6. A fixed permanent magnet 10 is provided in a position facing the end of the temperature-sensitive ferrite, and the temperature-sensitive ferrite 71 is connected to the reed switch 3 in the operating state in which the float 6 is moved downstream. A permanent magnet 1 is located on the outer periphery of the contact part and its end is fixed.
0, and the temperature-sensitive ferrite 71
A temperature-sensitive water flow switch made of ferrite, which has the property of rapidly decreasing magnetic permeability when the temperature of the water flow rises above the set temperature.