JPS5971946A - Anti-freezing apparatus for water heater - Google Patents

Abstract

PURPOSE:To enable to keep heat conduction surfaces in tight contact with each other and to increase the durability of the same, by enveloping a heating member having a temperature self-maintaining function by a resilient member made of a stable material. CONSTITUTION:A heating member 8 having a temperature self-controlling function is inserted into a resilient member 7 which is formed to be kept in tight contact with a curved surface of a pipe 6. The pipe 6 and the resilient member 7 are covered with an anti-freezing apparatus retaining means 9 from above the resilient member 7, and the retaining means 9 is fastened by a screw 10. The resilient member 7 is brought into tight contact with the pipe 6 by the relationship between strain and stress and the thermal expansion of the pipe 6 is absorbed by the resilient means 7, so that the coefficient of thermal conductivity is increased. Further, since the heating member 8 incorporates therein a temperature self-controlling mechanism, it is highly durable. An antifreezing apparatus 11 is operated by disposing a temperature-sensitive switch 13 at an upstream portion of a heat exchanger 12 where the temperature is lowest.

Description

[Detailed Description of the Invention] The industrial application field is based on the internal water 2 /
--Relating to an antifreeze device that prevents freezing in one passage.

2. Description of the Related Art Structures of Conventional Examples and Problems There are conventional antifreeze devices that utilize heat generated by electrical resistance, as shown in FIGS. 1 and 2.

FIG. 1 shows a heating element 1 surrounded by cement 2. In FIG. 2, a heating element 1' is wrapped with heat-resistant rubber 3 and aluminum foil 4, and attached with adhesive tape 5.

As an example, the state in which the antifreeze device shown in FIGS. 1 and 2 is attached to a pipe is shown in FIG.

In Fig. 3, the anti-freezing device attached to the vibro wraps the heating element 1 with cement 2, which is a rigid body, and it is difficult to make the cement 2, which is a rigid body, adhere to the vibro. A high degree of processing precision is required. Furthermore, damage to the cement 2 due to shock or the like causes a decrease in adhesion and a decrease in heat conduction, making it impossible to exhibit sufficient performance.

In order to prevent this, a filling material with high thermal conductivity can be used, but this has extremely poor workability and is expensive.

3. In Figure 4, the performance of heat conduction depends on the viscous force of the adhesive tape 5, and the heating element 1' constantly generates high temperature.
However, there were problems with long-term durability.

Purpose of the Invention The present invention solves the above-mentioned conventional drawbacks, and improves the adhesion of the heat conductive surface, which most affects the performance of this type of antifreeze device, further increases its durability, and reduces power consumption. purpose.

Structure of the Invention In order to achieve the above object, the antifreeze device of the present invention has a structure in which a heating element having a self-temperature maintenance function is wrapped in an elastic body made of a stable material.

The present invention focuses on the characteristics of elastic bodies.

In FIG. 6, the horizontal axis represents stress σ, and the vertical axis represents strain δ. In the elastic region, as shown in the figure, there is a linear relationship between stress σ and strain δ.

- For example, if an elastic body is brought into close contact with a pipe and pressed down to the dotted line in Fig. 6, a stress σ corresponding to the displacement δ will be applied from the pipe as a reaction force, and the pipe and the elastic body will be brought into complete contact.

Considering durability, it is a problem that the heating element constantly generates high temperatures, so one that has a self-temperature control function is selected as one of the heating elements. This character always keeps its own temperature constant, and when heat conduction is very good (when the external temperature is low), it produces high output, and in the opposite case, it produces low output. By using this, the durability of the elastic body is extended and the power consumption is reduced compared to one that constantly generates heat. In addition, instead of leaving the antifreeze device on all the time, a temperature sensing switch is installed at the lowest temperature point in the entire water passage so that the antifreeze device is turned on only when necessary. Activate. This has the effect of further saving power.

DESCRIPTION OF EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

In FIG. 7, a heating element 8 having a self-temperature control mechanism is inserted into an elastic body 7 which is molded so as to closely fit the curved surface of the pipe. Using the antifreeze device presser 9 to wrap around the entire vibro from above the elastic body 7, screw 1 is used.
Stop with o. The elastic body held down by the anti-freeze device presser 9 is brought into close contact with the vibro due to the strain-stress relationship as described above, and still sufficiently absorbs the thermal expansion of the vibro, improving thermal conductivity. Furthermore, the heating element 8 having an internal self-temperature control mechanism has better durability than a case where a general heating element is embedded due to its function.

FIG. 8 is a configuration diagram of a water heater in which the antifreeze device 11 is turned on and off using a temperature sensing switch.

A temperature sensing switch 13 is provided at the lowest temperature point upstream of the heat exchanger 12, and the antifreeze device 11 is activated. The reason why the temperature sensing switch 13 is attached to the upstream part of the heat exchanger 12 is that if it is downstream, the water temperature is higher than that upstream, and if it is set downstream, there is a possibility that the upstream part will freeze before the temperature sensing switch 13 is turned on. It is for this purpose.

By configuring as described above, the power is consumed more than if it is turned on all the time, and the durability of the antifreeze device 11 is also improved.

As described above, according to this embodiment, the antifreeze device is completely attached with a single screw, improving heat conduction, and furthermore, the self-temperature control mechanism and temperature sensing switch 13 have the effect of saving power and improving durability. can demonstrate.

Effects of the Invention As described above, according to the present invention, the following effects can be obtained.

0) Utilizing the strain-stress characteristics of the elastic body, it is possible to more completely adhere to the conductive body with a simple configuration.

B)) No matter what shape the conductive object has, it can be molded to suit that shape, and high thermal conductivity can be obtained.

(3) By using a heating element with a self-temperature control mechanism and turning it on and off with a temperature sensing switch, the durability of the antifreeze device can be improved and power consumption can be further reduced.

[Brief explanation of the drawing]

7/- Figure 1 is a cross-sectional view of a conventional antifreeze device in which the heating element is wrapped in cement, Figure 2 is a perspective view of a conventional antifreeze device that is attached with adhesive tape, and Figure 3 (A).
(B) is a sectional view showing the state in which the conventional product shown in Fig. 1 is installed, Fig. 4 is an external perspective view showing the state in which the conventional product shown in Fig. 2 is installed, and Fig. 5 is a sectional view of the antifreeze device of the present invention. FIG. 6 is an explanatory diagram of the operation of the elastic body; FIG. 7 is a sectional view showing the installation state of the antifreeze device according to an embodiment of the present invention; FIG. The figure is a configuration diagram showing a case where the same device is implemented in a water heater. 6... Pipe (thermal conductor), 7... Elastic body. 8゛°°゛°Heating element with self-temperature control self-tank, 9...
...Anti-freeze device holder, 11-"...Anti-freeze device. 12...Temperature sensing switch. Name of agent: Patent attorney Toshio Nakao and one other person No. 1
Figure 2 Figure 3 (p,) (B) Figure 4 Figure 5 ^ Figure 6 Figure 7 Figure 8

Claims (3)

[Claims] (1) Freezing prevention device for a water heater, comprising a heating element that generates heat through electric resistance and controls its own temperature, and a heat-resistant elastic body, the heating element being surrounded by the elastic body. (2) The antifreeze device for a water heater according to claim 1, wherein the heat conductive side of the elastic body is formed into the shape of a heat conductor that comes into contact with the elastic body. (3) A plurality of antifreeze devices each consisting of a self-temperature-controlled heating element and a heat-resistant elastic body are electrically connected in parallel, and a temperature switch is provided at the lowest temperature upstream of the heat exchanger. A freezing prevention device for a hot water heater, wherein the freezing prevention device is turned on and off by a temperature switch.