JPH0342596Y2 - - Google Patents

Description

[Detailed description of the invention] (a) Industrial application field This invention relates to a dew condensation prevention structure for a thermostat attached to the can of a hot water boiler.

(b) Conventional technology This type of thermostat has been developed since 1980.
As disclosed in Japanese Patent No. 2499, it is removably attached to the outer surface of the boiler can using a fixture fixed to the boiler can.

(c) Problems that the invention aims to solve The can body of a hot water boiler is covered with an insulating material such as glass wool, but the mounting part of the thermostat is insulated so that the thermostat can directly detect the temperature of the can body. material has been removed.

For this reason, when water is passed through the can body in high humidity conditions or when combustion is stopped, dew condensation occurs on the surface of the thermostat, resulting in a problem of poor insulation.

This idea was made in view of the above-mentioned facts, and was designed to prevent dew condensation in the thermostat attached to the can of a hot water boiler during high humidity or when water is passed through the can with combustion stopped. purpose.

(d) Means for solving the problem In this invention, in the structure for preventing condensation of a thermostat installed on the outer surface of the can of a hot water boiler, a a second insulating material placed on the insulating material and covering the mounting portion of the thermostat; a case placed on the insulating material and surrounding the thermostat; and the case is attached to the can body. The first heat insulating material and the second heat insulating material are compressed between the case and the can body by attaching the case to the can body using the screws.

(E) Effect Since the thermostat mounting part is kept warm by the second heat insulating material, the air inside the case is difficult to cool even when water is passed through the can body while combustion is stopped. Furthermore, by attaching the case to the can body with screws, the first insulating material and the second insulating material are held in a compressed state between the case and the can body, and are inserted into the case from between the case and the can body. This prevents air (moisture) from entering, which prevents condensation from forming on the surface of the thermostat.

(f) Embodiments Hereinafter, embodiments of this invention will be described in detail based on the drawings.

In Fig. 1, 1 is a hot water boiler can body, 2 is a can body insulation material such as glass wool (first insulation material),
3 is a bimetallic thermostat installed in the part of the can body 1 where there is no heat insulating material 2 (thermostat mounting part) to prevent dry firing; 4 is a fixing fitting for this thermostat 3, which is attached to the outer surface of the can body 1; It is fixed by welding. The fixture 4 has a notch 4a into which the thermostat 3 is fitted. The thermostat 3 also includes a mounting flange 3a and a pair of terminals 3b. The thermostat 3 is mounted in close contact with the can body 1 by sandwiching the mounting flange 3a between the can body 1 and two tassel pin screws 5 screwed into the fixing metal fitting 4. 6 is placed on the can insulating material 2, and the terminal 3b of the thermostat 3 is connected above the thermostat 3.
A heat insulating material (second heat insulating material) such as glass wool that covers the thermostat 3 with a curled open end placed on the heat insulating material 6 and surrounding the thermostat 3. case, and is fixed to the can body 1 with two screws 8. A lead wire 9 is connected to the terminal 3b of the thermostat 3 via a connecting terminal 10, and is led out of the case 7 from between the open end of the case 7 and the heat insulating material 6.

According to this embodiment, since the mounting part of the thermostat 3 is insulated by the heat insulating material 6, the air inside the case 7 is not easily cooled even when water is passed through the can body 1 while combustion is stopped. Become. In addition, by attaching the case 7 to the can body 1 with screws 8, the heat insulating material 6 and the can body insulating material 2 are compressed, so the inside of the case is almost sealed, and even in high humidity, moisture can be kept between the case 7 and the can body. It becomes difficult to flow into the case 7 from between the As a result, dew condensation on the surface of the thermostat 3 is prevented, and there is no fear that the thermostat 3 will generate a false signal due to poor insulation or that electrical leakage will occur.

In the example described above, when water at 10°C is passed through the can body 1 for 3 hours with combustion stopped, the insulation resistance between the terminals 3b of the thermostat 3 is 500MΩ.
That's all.

On the other hand, as shown in Fig. 2, when the thermostat 3 is attached to the can body 1 without using the heat insulating material 6 and the case 7, the insulation resistance will be lower under the same conditions.
It was 150MΩ. Also, as shown in Fig. 3, a rubber cap 11 is attached only to the terminal part of the thermostat 3.
The insulation resistance of the one covered with was 5MΩ. Furthermore, as shown in FIG.
The insulation resistance of the case where the entire mounting part was covered with the heat insulating material 12 was 50 MΩ.

This shows that this example exhibits a high insulation effect by using the case 7 and the heat insulating material 6 together.

Furthermore, in this embodiment, the lead wire 9 is led out from the case 7 between the curled open end of the case 7 and the heat insulating material 6, so the lead wire 9 can be connected without damaging the sheathing of the lead wire 9. It can be taken out of the case in an airtight manner, and separate members such as bushings are not required.

(g) Effects of the invention This invention is structured as described above, so
It provides good heat retention at the thermostat mounting area, prevents moisture from entering, and prevents condensation on the thermostat surface, even in high humidity or when water is flowing through the can body when combustion is stopped. The insulation condition of the terminal section of the thermostat is improved, and reliability and safety can be improved.

[Brief explanation of the drawing]

Fig. 1 is a cross-sectional view of a thermostat dew condensation prevention structure showing an embodiment of this invention, and Figs.
Each figure is a sectional view showing a comparative example of this invention. DESCRIPTION OF SYMBOLS 1... Can body, 2... Can body insulation material (first insulation material), 3... Thermostat, 6... Insulation material (second insulation material), 7... Case, 8... Screw.

Claims (1)

[Scope of utility model registration request] In a structure for preventing condensation of a thermostat installed on the outer surface of a can of a hot water boiler, there is a first insulating material that covers the can leaving the mounting part of the thermostat, and a first insulating material that is placed on this insulating material and that protects the thermostat. A second insulating material that covers the mounting part of the thermostat, a case that is placed on the insulating material and surrounds the thermostat, and a screw that attaches the case to the can body. 1. A dew condensation prevention structure for a thermostat, characterized in that the first heat insulating material and the second heat insulating material are compressed between the case and the can body.