JPH0332934Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] This invention relates to a heat exchanger installed in household gas appliances such as water heaters and bathtubs.

[Prior Art] Conventionally, a heat exchanger for a gas appliance has an exchanger body formed by attaching fins to a heating tube placed on top of an inner body of a metal cylinder having a substantially rectangular cross section. It is constructed by wrapping a heating tube around the outer circumferential surface of the inner shell before the exchanger main body. Then, the combustion chamber of the gas burner is formed inside the inner shell, and the inner shell is cooled by the water flow in the heating tube wrapped around the outer circumferential surface of the inner shell, reducing the radiant heat to the housing of the gas appliance. It is configured as follows.

[Problems to be solved by the invention] However, as mentioned above, in a water-cooled heat exchanger in which a heating tube is wrapped around the outer circumferential surface of the inner shell, condensation occurs after heating due to the water flow inside the heating tube. This may cause freezing, rust, corrosion, etc., and there is a risk of damage to the inner shell. Therefore, it cannot necessarily withstand long-term use, and its durability is not satisfactory. Further, the structure is such that the heating tube is connected to the exchanger body after being wrapped around the outer peripheral surface of the inner shell, which is complicated and expensive, and the manufacturing process is complicated, which is not preferable from the viewpoint of manufacturing cost.

This invention aims to solve these problems by providing a heat exchanger for gas appliances with a new configuration in which the inner shell is formed using ceramic fibers, thereby eliminating the dangers of condensation, rust, corrosion, etc. exclude,
It is an object of the present invention to provide a heat exchanger for gas appliances that has excellent durability, has a simple structure, and can be manufactured at low cost.

[Means for solving the problem] In order to solve the above problem, this invention
An inner shell is formed from a ceramic fiber formed into a cylinder with a substantially rectangular cross section, a metal plate is attached to the outer circumferential surface of the inner shell, and the metal plate is attached at a distance within the housing of the gas appliance using a mounting bracket. Hold the inner shell in place, attach a number of fins to the heating tube to form the exchanger body, attach the exchanger body to the metal plate using support fittings, and attach the exchanger above the inner shell. The main body is placed on it to form a heat exchanger for gas appliances.

[Function] In the heat exchanger for gas appliances having such a configuration, the combustion chamber of the gas burner is formed in the internal space of the inner shell formed of ceramic fibers. And, due to the insulation effect of ceramic fiber,
The metal plate attached to the outer circumferential surface of the inner shell is always kept at an appropriate temperature. In addition, the inner shell is reinforced by attaching a metal plate to the outer peripheral surface of the inner shell, and the inner shell is fixed in a predetermined position and the exchanger body is attached to the inner shell using mounting brackets and support metal fittings. will be held.

[Example] The configuration and effects of this invention will be specifically explained below with reference to the embodiment shown in the drawings.

The drawing shows an embodiment of this invention in a gas water heater, in which an inner shell 10 is formed by forming a ceramic fiber into a cylinder with a substantially rectangular cross section, and a metal plate 20 is attached to the outer peripheral surface of the inner shell 10. There is. The metal plate 20 is provided for fixing the inner shell 10 and attaching the exchanger main body 40, as will be described later.
It may be formed so as to cover the entire outer circumferential surface of the inner barrel 10, or may be formed so as to cover a part of the outer circumferential surface. A plurality of studs 21 are provided protruding from the inner surface of the metal plate 20, and support portions 22 bent inward are provided at the upper and lower ends of the metal plate 20. The upper and lower end surfaces of 10 are held by the support part 22,
A metal plate 20 is attached to the outer peripheral surface of the inner shell 10 to reinforce the inner shell 10. The metal plate 20 is held spaced apart within the housing 31 of the gas appliance using a plurality of fittings 31, thereby fixing the inner shell 10 in a predetermined position. An exchanger body 40 is formed by attaching a large number of parallel fins 41 to a heating tube 42 through which a water flow flows, and the exchanger body 40 is attached to a metal plate 20 using a support fitting 43.
The exchanger main body 40 is placed above the inner shell 10.
The internal space of the inner shell 10 forms a combustion chamber 50, and gas burners 60 having a predetermined combustion capacity are arranged in parallel below the combustion chamber 50. Then, the combustion gas supplied to the gas burner 60 is ignited, forms a flame in the combustion chamber 50, and burns, heating the exchanger main body 40, and heating the heating tube 42.
Heats the water flow inside.

[Effects of the invention] The characteristic functions and effects of this invention are as follows.

The inner shell 10 is formed of a ceramic fiber formed into a cylinder having a substantially rectangular cross section, and the combustion chamber 50 of the gas burner 60 is formed in the internal space of the inner shell 10.
Due to the heat insulating effect of the ceramic fibers, the metal plate attached to the outer peripheral surface of the inner shell 10 is kept at an appropriate temperature without being abnormally overheated, and the risk of damage to the instrument due to the radiant heat of the inner shell 10 can be eliminated. The thickness of the inner shell 10 varies depending on the design conditions of the gas appliance, but according to tests conducted by the applicant, when the combustion capacity of the gas burner 60 is 30,000 kcal/h and the thickness of the ceramic fiber is 15 mm, the thickness of the combustion chamber 50 is 700
~800℃, the outer peripheral surface of the inner shell 10 is several tens of degrees Celsius,
We were able to obtain practical and satisfactory values.

In addition, the ceramic fibers forming the inner shell 10 not only have an excellent heat insulating effect, but also have no fear of rust or corrosion. There is no need for wrapping, the risk of condensation is eliminated, and a heat exchanger with excellent durability can be obtained.

In addition, the inner shell 10 is reinforced by attaching a metal plate 20 to the outer peripheral surface of the inner shell 10, and the inner shell 10 is fixed to the metal plate 20 in a predetermined position using a mounting bracket 31. The exchanger main body 40 is attached to the inner shell 10 using the above method, and the entire structure is made rigid. Then, the mounting bracket 31, the support bracket 43, etc.
Since the component parts are arranged rationally, it is easy to assemble and manufacture, and the structure is simpler than conventional products, so it can be manufactured at low cost. It is effective.

[Brief explanation of the drawing]

The drawings show an embodiment of this invention, with FIG. 1 being a front sectional view and FIG. 2 being a perspective view of the main parts. 10... Inner shell, 20... Metal plate, 30... Housing, 31... Mounting bracket, 40... Exchanger body, 4
1...Fin, 42...Heating tube, 43...Supporting metal fittings.

Claims (1)

[Scope of utility model registration request] An inner shell 10 is formed of a ceramic fiber formed into a cylinder with a substantially rectangular cross section, a metal plate 20 is attached to the outer peripheral surface of the inner shell 10, and a mounting bracket 31 is used to attach the metal plate 20 to the casing 30 of the gas appliance. Keep the metal plate 2
0 and fix the inner shell 10 in a predetermined position, attach a number of fins 41 to the heating tube 42 to form the exchanger body 40, and use the support fittings 43 to attach the exchanger body 40 to the metal plate 20. A heat exchanger for a gas appliance configured by mounting an exchanger main body 40 above an inner shell 10.