JPH025295Y2 - - Google Patents

Description

[Detailed description of the invention] [Field of application and overview of the invention] The present invention relates to an installation structure for an overheat detection switch in a device for preventing dry heating of a gas bath kettle. This aims to improve the responsiveness of the overheat detection switch by placing it facing the upper opening of the pipe, and at the same time, it simplifies the installation of a heat receiver that promotes heat transfer to the overheat detection switch. .

[Prior art and its problems] As a device for preventing dry heating of the heat exchanger, an overheat detection switch 1 is attached to the water jacket 20 of the heat exchanger 2 to detect the overheating state of the heated part in the heat exchanger. A configuration is known in which the overheat detection switch 1 is inserted into a thermocouple circuit of a thermocouple safety valve.

Moreover, in order to improve the responsiveness of this overheat detection switch 1, as disclosed in Utility Model Publication No. 53-27160,
An overheat detection switch mounting structure is adopted.

This conventional type has a structure in which a rod 10 is provided so as to pass through a connecting pipe 21 that connects water jackets 20, 20 provided in a heat exchanger 2, and an overheat detection switch 1 is connected to this rod 10. be. In this case, the rod 10 contacts the hot water on the high temperature side in correspondence with the connecting pipe 21 that connects the upper parts of the water jackets 20, 20, and the protruding portion of the rod 10 from the connecting pipe 21 is water jacket 20,2
Since the overheat detection switch 1 is exposed to high-temperature exhaust gas during zero heating, the overheat detection switch 1 quickly responds when the engine is idle.

However, this conventional switch has problems in that its responsiveness is not sufficient and, moreover, it is troublesome to install the overheat sensing switch 1.

This is because the overheat detection switch 1 is operated by heat transfer from the rod 10, so even if the water temperature in the connecting pipe 21 rises, the temperature of the sensing part of the overheat detection switch 1 immediately increases accordingly. This is because it does not rise. In addition, when installing the rod 10, a through hole for penetrating the rod is formed in the connecting pipe 21,
This is because after passing the rod 10 through this, the penetrating portion must be welded or sealed in an airtight state.

[Technical Problem] The present invention is designed to solve the following problem: When an overheat detection switch 1 is attached to a heat exchanger and the inside of the heat exchanger becomes overheated, the output from the overheat detection switch 1 is used to prevent the heat exchanger from overheating. In order to make the overheat sensing switch 1 respond sensitively when the heat exchanger becomes abnormally overheated, the overheat sensing switch 1
In order to simplify the installation of the overheat detection switch 1, the sensing part of the overheat detection switch 1 is simply installed in the heat exchanger 20, and the sensing part of the overheat detection switch 1 is located inside the heat absorption pipe in the heat exchanger. This is the technical issue.

[Technical Means] The technical means of the present invention taken to solve the above-mentioned technical problem is that the heat exchanger is constructed by installing a plurality of heat absorption pipes 22, 22 in an inclined state between the water jackets 20, 20 facing each other. The overheat sensing switch 1 is attached to the outer wall 23 of the water jacket 20 facing the upper opening of the heat absorption pipe, and the sensing part 11 of the overheat sensing switch 1 is connected to the water jacket 20.
On the other hand, the heat receiving body 12 is housed in the upper opening of the heat absorption pipe 22 and has a plate-shaped portion 15 that is in contact with or in close proximity to the sensing portion 11.
The holding frame 13 is fitted and held within the heat absorption tube 22.

[Operation] The above technical means of the present invention operates as follows.

In the heat exchanger 2 of the above type, the water jacket 20
The heat absorption pipes 22, 22 each having a large number of fins are welded and integrated between the opposing inner walls of the heat absorption pipes 2.
The water jacket 20 is constructed by opening both ends of the water jackets 2 and 22 into the water jacket, and then integrally covering the outer wall 23 with the inner wall. Prior to attaching this outer wall 23, the heat receiving body 12 is inserted into the upper opening of one of the heat absorption pipes 22, and the overheat sensing switch 1 is placed on the outer wall 23 at a position facing the plate-shaped portion 15 of this heat receiving body. If this is installed, the sensing portion 11 of the overheat sensing switch 1 and the plate-like portion 15 will come into contact with or be close to each other.

Next, when the heat exchanger 2 becomes abnormally heated, the temperature inside the heat absorption tube 22 rises, and the temperature at the upper opening of the heat absorption tube 22 becomes the highest temperature. However,
This high temperature part has the sensing part 1 of the overheat detection switch 1.
1 is facing, and this sensing part 11 is
The holding frame 13 is inserted into the upper end of the holding frame 13 and the plate-shaped part 15 is integral with the holding frame 13. Therefore, since this sensing part 11 is in a state where heat is transferred from the high-temperature hot water and from the heat receiving body 12 that matches the temperature of this hot water or the wall surface temperature of the heat absorption tube 22, the temperature of the heat absorption tube 22 is abnormally heated. When it reaches a certain temperature, it senses this temperature immediately. In other words, there is almost no difference between the temperature of the upper part of the heat absorption tube 22 and the temperature of the sensing part 11.

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

Since there is almost no difference between the temperature of the upper part of the heat absorption pipe 22 and the temperature of the sensing part 11, the heat absorption pipe 22
The time difference that occurs between the time when the internal temperature reaches an abnormal overheating temperature state and the time when the overheating detection switch 1 responds is significantly reduced, and the responsiveness of the overheating detection switch 1 is improved compared to conventional ones. The amount of scale that adheres to the heat exchanger 2 decreases when the temperature decreases. Therefore, the life of the heat exchanger 2 becomes longer.

In addition, in order to improve the responsiveness of the overheat detection switch 1, the heat receiving body 12 is simply inserted into the upper part of the heat absorption tube 22, so it is easier to assemble it than the conventional method in which a rod is fixed through the connecting tube. It's easy.

[Embodiment] In an embodiment of the present invention, the holding frame 13 is
It was inserted so that it was in contact with the inner wall of the

According to this embodiment, the plate-shaped portion 15 is
Since the temperature approximates the temperature of the tube wall of the heat absorption tube 22, which has a higher temperature than the hot water in the hot water, the response is further improved.

[Example] Hereinafter, an example of the present invention will be described based on FIGS. 1 to 4.

In this embodiment, the heat exchanger 2 is formed into a rectangular parallelepiped, and the water jackets 20 are formed into a rectangular cylinder shape, and the inner walls 2 of the bodies of the planar water jackets 20 facing each other are
4 and 24 are communicated with each other by a plurality of heat absorption pipes 22 and 22 that are inclined from one side to the other,
A pair of communication water pipes 3, 3 are attached to the outer wall 23 of the water jacket 20, with the upper ends of the heat absorption pipes 22 facing each other. The interior of the water jacket 20 and the bathtub (not shown) are connected to each other by these communication water pipes 3, 3, thereby forming a circulation circuit between the heat exchanger 2 and the bathtub.

Next, the heat receiving body 12 consisting of the holding frame 13, the sensing section 11, and the stopper 14 is assembled as shown in FIGS.
The structure is as shown in the figure, and the holding frame 13 inserted into the heat absorption tube 22 is an annular body having a cross-sectional shape that substantially matches the cross section of the inner wall of the heat absorption tube 22, and is manufactured by bending a metal plate. In order to facilitate this manufacturing, the holding frame 13 is constructed by welding a pair of symmetrical halves together at both upper and lower ends, and the welded portions are connected to the upper and lower pipe walls of the heat absorbing tube 22. It is made to be at right angles to. Furthermore, the sensing section 11 is constructed integrally between the ends of connecting pieces 16, 16 that are connected to the halves of the holding frame 13, and the relationship between the sensing section 11 and the holding frame 13 is defined by a heat absorption tube. 22 and the outer wall 23 and the mounting position of the overheat detection switch 1. Further, in this embodiment, the stopper 14 is a tongue piece that projects outward from the side edge of the holding frame 13 and the lower edge of the connecting piece 16, and these tongue pieces are integrated with the holding frame 13 and the connecting piece 16. It is formed.

In addition, the overheat detection switch 1 is set as shown in Fig. 2.
It is fitted into a through hole 25 formed in the outer wall 23, and its periphery is fixed and integrated with the outer periphery in an airtight state by welding. As for the mounting structure of the overheat detection switch 1, in addition to the structure described above, a combination of a packing seal and a screw fixing can also be adopted.

[Brief explanation of the drawing]

Fig. 1 is an external perspective view of an overheat detection switch 1 according to an embodiment of the present invention, Fig. 2 is a sectional view of its main parts, Fig. 3 is a side view thereof, Fig. 4 is a front view thereof, and Fig. 5 is a conventional It is an explanatory diagram of an example, and in the figure, 1... overheat sensing switch, 10... rod, 11... sensing section, 12...
Heat receiving body, 13... Holding frame, 15... Plate portion, 20
...Water jacket, 21 ... Connecting pipe, 22 ... Endothermic pipe.

Claims (1)

[Scope of claim for utility model registration] An overheat detection switch 1 is attached to the heat exchanger,
When the inside of the heat exchanger becomes overheated, the output from the overheat detection switch 1 is used to stop the heating of the heat exchanger.
A plurality of heat absorption pipes 22, 22 are connected to each other in an inclined state between 0 and 0, and an overheat detection switch 1 is attached to the outer wall 23 of the water jacket 20, where the upper openings of the heat absorption pipes face each other. The sensing part 11 of the sensing switch 1 is made to protrude into the water jacket 20, and on the other hand, the heat receiving body 12 having a plate-like part 15 facing or close to the sensing part 11 is housed in the upper opening of the heat absorption pipe 22. , this heat receiving body 12
The holding frame 13 is fitted and held in the heat absorption pipe 22.
Mounting structure for overheat detection switch of dry-heating prevention device. A mounting structure for an overheat detection switch of a dry heating prevention device according to claim 1, wherein the holding frame 13 is inserted so as to be in contact with the inner wall of the heat absorption pipe 22.