JPH03102114A - Heat exchanger for firing type heater - Google Patents

Abstract

PURPOSE:To form at least a fluid passage and reduce the production cost with an increase in heat-exchange efficiency by a method wherein a ber-like heat radiation fin is spirally wound around the outer circumference of a gas introducing duct, and both ends of the fin are fixed on the outer surface of the gas introducing duct. CONSTITUTION:A cylindrical gas introducing duct 20 having openings on both ends and heat-absorbing fins 25 on the inner surface is produced by extrusion- molding method, for example. A round bar-like heat-radiation fin 30 is spirally wound around the outer surface of the gas introducing duct 20, and at least both ends 30a and 30b of the heat-radiation fin 30 are fixed on the outer surface of the gas introducing duct 20 to form the spiral heat-radiation fin 30 around the outer surface 20a of the gas introducing duct 20. Therefore, the spiral heat- radiation fin 30 can be easily formed around the outer surface 20a of the gas introducing duct 20, resulting in a reduction in the production cost. Moreover, two or more fluid passages are formed by the two or more bar-like fins, so that the heat-exchange efficiency is improved, boiling is avoided and the duct is prevented from vibrating.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field in Icheon) The present invention relates to a heat exchanger for a combustion type heater suitable for being mounted on a vehicle that heats engine cooling water.

(Prior Art) A conventional heat exchanger for a combustion type heater includes a gas introduction pipe through which combustion gas passes, an outer case provided on the outside of the gas introduction pipe, and an outer circumferential surface of the gas introduction pipe. a fluid passage formed between the inner circumferential surfaces of the outer case, heat receiving fins and heat dissipating fins are provided on the inner circumferential surface and outer circumference of the gas introduction pipe, respectively; There is a technique in which the outer case is provided with an inlet through which the fluid flows in and an outlet through which the fluid that has received heat while passing through the fluid passage flows out (Japanese Unexamined Patent Publication No. 62-77522).

In this conventional technology, in order to efficiently receive heat from the gas introduction tube that has become hot due to heat exchange with the combustion gas and warm the fluid passing through the fluid passage, the outer circumferential surface of the gas introduction tube is heated. A single spiral heat radiation fin is provided integrally with the gas introduction pipe.

(Problem to be Solved by the Invention) However, in the above-mentioned conventional technology, the gas introduction pipe with the spiral heat dissipation fins integrated into it must be integrally molded by die-casting, resulting in a complicated shape. This increases the manufacturing cost, and since there is only one fluid passage, the heat exchange efficiency is poor and there is a risk of boiling.

The present invention has been made in view of these conventional problems, and aims to provide a heat exchanger for a combustion type heater that reduces manufacturing costs and has good heat exchange efficiency.

(Means for Solving the Problems) In order to achieve this object, the present invention provides a gas introduction pipe through which combustion gas passes, an outer case provided on the outside of the gas introduction pipe, and a gas introduction pipe. and a fluid passage formed between the outer circumference of the gas introduction pipe and the inner circumference of the outer case, heat receiving fins and heat radiation fins are provided on the inner circumference and the outer circumference of the gas introduction pipe, respectively, and In a heat exchanger for a combustion type heater, in which an inlet for allowing a fluid to flow into a passage and an outlet for discharging a fluid that has received heat while passing through the fluid passage are provided in the outer case, the outer periphery of the gas introduction pipe is At least one rod-shaped heat dissipation fin is spirally wound from the inlet side to the outlet side, and at least both ends of the rod-shaped heat dissipation fin are attached to the outer peripheral surface of the gas introduction pipe. It is fixed.

(Function) In the heat exchanger for the combustion type heater, a rod-shaped heat radiation fin is spirally wound around the outer periphery of the gas introduction pipe, and at least both ends of the rod-shaped radiation fin are fixed to the outer peripheral surface of the gas introduction pipe. Accordingly, a spiral heat dissipating fin is formed on the outer peripheral surface of the gas introduction tube, thereby forming at least one fluid passage.

(Example) Hereinafter, each example of the present invention will be explained based on the drawings. Fig. 1 is a longitudinal sectional view showing a combustion type heater equipped with a heat exchanger according to a first example of the present invention. This combustion type heater is a type of heater that warms water sent from a pump by heat exchange with combustion gas, and is installed in a vehicle that heats engine cooling water. This combustion type heater is composed of a combustor 1 and a heat exchanger 2.

The combustor 1 is provided with a combustion tube 4 whose interior at one end forms a combustion chamber 3, a disk-shaped wick 5 made of ceramic fiber, a holding member 6, and a case 7.

The combustion tube 4 is fixed to the case 7 via a flange 4b formed on its outer periphery. One end of the combustion tube 4 is closed with a lamp wick 5, and the other end extends to the inside of the heat exchanger 2 to form a gas guide tube portion 4a. An opening forming member 8 having an opening 8a through which flame and combustion gas generated within the combustion chamber 3 pass is fixed to the inner periphery of the combustion tube 4.
The flame and combustion gas generated in the combustion chamber 3 enter the gas guiding portion 4a through the opening 8a. Further, a large number of air inflow holes 9 are bored in the peripheral wall on one end side of the combustion tube 4, and the combustion air introduced into the air passage 10 on the outside of the combustion tube 4 passes through the air inflow holes 9. Combustion chamber 3
It is now being introduced into the

The holding member 6 is fixed to one end side of the case 7,
The lamp wick 5 is fixed to this holding member 6. This holding member 6 is formed with a fuel passage 6a and an opening 6b.

Another case 11 is fixed to one end of the case 7. This case 2 includes a fuel supply bomb 13 for supplying liquid fuel to the lamp wick 5 via a fuel supply pipe 12 and the fuel passage 6a, and a fuel supply bomb 13 for supplying combustion air to an air passage lea in the case 11 and an opening in the holding member 6. 8 through 6b; 1 air passage 1
A swirl blower l4 for supplying combustion air to the air is installed.

Further, a globe lug 15 is detachably attached to the peripheral wall of the case 7, and an ignition portion 15a of the globe lug 15 protrudes into the combustion chamber 3.

The heat exchanger 2 includes a gas guide cylinder portion 4a of the combustion cylinder 4.
a cylindrical gas introduction pipe 20 located outside of the case 7 and having one end fixed to the other end of the case 7;
An outer case 2l is provided, which is located outside of the case 7 and has one end fixed to the other end of the case 7. Gas introduction'1
A fluid passage 22 is formed between the outer peripheral surface 20a of the outer case 20 and the inner peripheral surface 21a of the outer case 2l.

As shown in FIGS. 1 to 13, a bottom swallow 23 is fixed to the other end of the gas introduction pipe 20 by welding or the like, and the gas generated in the combustion chamber 3 and the gas guide pipe 4a of the combustion pipe 4 are Combustion gas passing through the interior is made a U-turn by the bottom cover 23, and the combustion gas passes through the combustion gas passage 24 between the gas guide tube 4a and the gas introduction pipe 20.
It is now being introduced into the A large number of heat absorbing fins 25 are protruded from the inner periphery of the gas introduction pipe 20 at equal intervals of tlH in the circumferential direction. In this way, the cylindrical gas introduction pipe 2 is open at both ends and has a large number of heat-absorbing fins 25 on the inner peripheral surface.
0 can be made, for example, by extrusion.

As shown in FIG. 1, the outer case 2l has an inlet 26 that allows water sent from a bomb (not shown) to flow into the fluid passage 22, and an inlet 26 that allows water that has received heat while passing through the fluid passage 22 to flow out. An outflow port 27 is provided to allow the air to flow through the air.

An exhaust port 28 is provided in the case 7 for discharging the combustion gas that has passed through the combustion gas passage 24.

Furthermore, as shown in FIGS. 1 to 3, round rod-shaped heat dissipation fins 3 are provided on the outer circumferential surface 20a of the gas introduction pipe 20.
0 is spirally wound from the inlet 26 side to the outlet 27 side. This round rod-shaped heat dissipation fin 30 has at least both ends 30a and 30b connected to the gas introduction pipe 20.
It is fixed to the outer circumferential surface 20a of the holder by threading or welding (see Fig. 2).

Next, the operation of the combustion type heater having the above configuration will be explained.

When heating is started by turning on an operation section (not shown), combustion air is supplied to the air passage 11a in the case Jl and the opening 6b of the holding member 6 by the swirl blower 14 for supplying combustion air.
, is introduced into the combustion chamber 3 via the air passage 10 and the air inlet 9 of the combustion tube 4. On the other hand, fuel supply pump 1
3, the liquid fuel t1 is supplied to the lamp wick 5 through the fuel supply pipe 12 and the fuel passage 6a, and is temporarily impregnated into the lamp wick 5.

When a voltage is applied to the globe lug l5 and its ignition part]5a becomes high temperature, the liquid fuel impregnated in the lamp wick 5 is vaporized, and a mixture of the vaporized liquid fuel and combustion air is generated in the combustion chamber 3. It ignites inside and creates a flame.

The flame generated in the combustion chamber 3 and its high temperature combustion gas are
The gas passes through the opening 8a and the gas guiding portion 4a, is introduced into the combustion gas passage 24 through the bottom cover 23, passes through the combustion gas passage 24, and is discharged from the discharge port 28.

While the combustion gas passes through the combustion gas passage 24, heat is transferred from the combustion gas to the endothermic fins 25, and the gas introduction pipe 20 becomes hot.

On the other hand, water flowing in from the inlet 26 flows toward the outlet 27 while swirling within the fluid passage 22 while being guided by the round rod-shaped radiation fins 30 . While the water flows in the fluid passage 22 in this manner, the water absorbs heat from the heat radiation fins 30 and the gas introduction pipe 20, becomes warm, flows out from the outlet 27, and heats the engine cooling water, thereby heating the engine cooling water. The air is heated by a heater core (not shown) installed inside the vehicle.
ltThe room is heated.

According to the first embodiment, the cylindrical gas introduction tube 20, which is open at both ends and has a large number of heat absorption fins 25 on the inner peripheral surface, is made by extrusion molding, for example, and the outer peripheral surface 20a of the gas introduction tube 20 is rounded. The spiral heat dissipation fin 30 is formed on the outer circumferential surface 20a of the gas introduction pipe 20 by simply winding the rod-shaped heat dissipation fin 30 in a spiral shape and fixing at least both ends 30a, 30b of the heat dissipation fin 30 to the outer circumference 20a. . Therefore, the spiral heat radiation fins 30 are attached to the outer periphery 20a of the gas introduction pipe 20.
It can be easily installed on the device, and manufacturing costs can be reduced.

Next, a second embodiment of the present invention will be described based on FIG.

In this second embodiment, a plurality of round bar-shaped heat dissipating fins (
In this embodiment, two wooden round bar-shaped radiation fins 30, 3]
) are spirally wound and fixed on the outer circumferential surface 20a of the gas introduction pipe 20 at approximately equal intervals. Other configurations are
This is the same as the first embodiment described above.

According to this second embodiment, the radiation fins 3 are shaped like two wooden round rods.
0.31 is spirally wound around the outer periphery 20a of the gas introduction pipe 20 at approximately equal intervals, so that the radiation fins 30, 3
] increases, and the heat transfer m (heat flow rate) per area of the heat radiation fins 30, 31 and the outer periphery 20a of the gas introduction pipe 2o decreases. As a result, the water passing through the fluid passage 22 becomes difficult to boil on the outer circumferential surface 20a of the gas introduction pipe 20, and as a result, the boiling of water causes the outflow port 22 to boil.
This prevents the piping connected to 7 from vibrating, and
This prevents the gas introduction pipe 2o and the outer case 21 from melting due to boiling of water. By avoiding boiling of water in this way, a stable and highly efficient heat exchanger 2 can be obtained.

In each of the above embodiments, the combustion gas from the combustor 1 is used as the combustion gas as a heat source, and water is used as the fluid heated by heat exchange with the combustion gas. Even if exhaust gas is used instead, or air is used instead of water, the same effects as in each of the above embodiments can be obtained.

Furthermore, in each of the above embodiments, the combustion gas passing through the gas guide cylinder part 4a of the combustion cylinder 4 is made a U-turn by the bottom cover 23, and the combustion gas between the gas guide cylinder part 4a and the gas introduction pipe 20 is The gas is introduced into the gas passage 24, and round rod-shaped heat dissipating fins 30 and 31 are provided on the outer periphery 20a of the gas introduction pipe 2o.
Although the gas introduction pipe provided with heat dissipating fins in the present invention is not limited to the gas introduction pipe 20 described above, the gas introduction pipe in which the combustion gas passes inside and has heat receiving fins on the inner circumference is described. If it is a pipe, the same effects as in each of the above embodiments can be obtained.

(Effects of the Invention) As detailed above, the heat exchanger for a combustion type heater according to the present invention includes a gas introduction pipe through which combustion gas passes, and an outer case provided on the outside of the gas introduction pipe. and a fluid passage formed between the outer peripheral surface of the gas introduction pipe and the inner peripheral surface of the outer case, and heat receiving fins and heat radiation fins are provided on the inner and outer peripheries of the gas introduction pipe, respectively. and an inlet for allowing fluid to flow into the fluid passage, and an outflow for letting out the fluid that has received heat while passing through the fluid passage.
In the heat exchanger for the combustion type heater, in which a heat exchanger for a combustion type heater is provided in the outer case, at least one rod-shaped radiation fin is spirally arranged on the outer peripheral surface of the gas introduction pipe from the inlet side to the outlet side. At least one rod-shaped heat dissipation fin is wound around the outer circumferential surface of the gas introduction tube, and at least both ends of the rod-shaped heat dissipation fin are fixed to the outer circumferential surface of the gas introduction tube. By simply winding the rod-shaped heat dissipating fins into the outer circumference of the gas introduction tube and fixing at least both ends of the rod-shaped heat dissipation fins to the outer circumference of the gas introduction tube, a spiral heat dissipation fin is formed on the outer circumference of the gas introduction tube. Therefore, the spiral heat radiation fins can be easily provided on the outer circumferential surface of the gas introduction pipe, and manufacturing costs can be reduced. In addition, by providing multiple fluid passages with multiple rod-shaped fins, heat exchange efficiency is improved.
Boiling is avoided and piping does not vibrate.

[Brief explanation of drawings]

1 to 3 show a first embodiment of the present invention, FIG. 1 is a longitudinal sectional view showing a combustion type heater equipped with a heat exchanger according to the first embodiment, and FIG. FIG. 3 is a plan view showing a gas introduction pipe wrapped with heat dissipation fins, FIG. 3 is a sectional view taken along line IJ-11 in FIG. 2, and FIG. It is a top view showing a tube. 2... Heat exchanger, 20... Gas introduction pipe, 20a...
・Outer periphery, 21... Outer case, 21a... Inner circumferential surface, 22... Fluid passage, 25... Heat receiving fin, 26...
- Inlet, 27... Outlet, 30.31... Radiation fins, 30a, 30b... Both ends. 2nd map 3rd map area 4th district

Claims (1)

[Claims] 1. A gas introduction pipe through which combustion gas passes, an outer case provided on the outside of the gas introduction pipe, and a fluid passage formed between the outer peripheral surface of the gas introduction pipe and the inner peripheral surface of the outer case. heat receiving fins and heat radiating fins are provided on the inner peripheral surface and outer peripheral surface of the gas introduction pipe, respectively, and an inlet for introducing the fluid into the fluid passage and an inlet for receiving heat while passing through the fluid passage. In a heat exchanger for a combustion type heater, in which an outlet through which fluid flows out is provided in the outer case, at least one rod-shaped heat dissipating fin is provided on the outer peripheral surface of the gas introduction pipe from the inlet side to the outlet. A heat exchanger for a combustion type heater, characterized in that the rod-shaped radiation fins are spirally wound toward the side, and at least both ends of the rod-shaped radiation fins are fixed to the outer peripheral surface of the gas introduction pipe.