JPH0740679Y2 - Exhaust heat recovery device for engine - Google Patents

Description

[Detailed Description of the Invention] << Industrial Application Field >> The present invention is an engine having an exhaust gas purification function for heating a heat medium liquid (mainly water) by using engine exhaust as a heat source for various purposes. The exhaust heat recovery device is used for heat pump devices and co-generation devices.

<Prior art> In recent years, in order to effectively utilize the thermal energy that the exhaust gas discharged from the engine has, a gas-liquid heat exchanger is arranged in the exhaust gas discharge passage, and the gas inside the gas-liquid heat exchanger is arranged. It is proposed that heat is exchanged between the exhaust gas flowing through the passage and the cooling liquid flowing through the liquid chamber of the gas-liquid heat exchanger.

Conventionally, as such a heat recovery device, for example,
-39169 publication. This forms an exhaust block by forming a cooling liquid chamber on the outer periphery of the exhaust outlet pipe connected to the exhaust port of the engine, and a gas-liquid heat exchanger is mounted and fixed on the upper surface of this exhaust block, and the gas of the exhaust outlet pipe is Directly connect the outlet to the gas inlet of the gas-liquid heat exchanger, and
The exhaust gas outlet of the gas-liquid heat exchanger is connected to the muffler, and the liquid chamber of the gas-liquid heat exchanger is connected to the cooling liquid chamber of the exhaust block.

<Problems to be solved> In the conventional heat recovery device, since the exhaust gas outlet of the exhaust block and the exhaust gas inlet of the gas-liquid heat exchanger are directly connected, the exhaust gas is directly heated by the gas-liquid heat. Although it will flow into the core part of the exchanger, since the exhaust gas of the engine contains harmful gas components, this harmful gas component also directly enters the core part of the gas-liquid heat exchanger. It will flow in. Therefore, there is a problem that the core portion of the gas-liquid heat exchanger is likely to be damaged early.

Therefore, an exhaust gas purifier such as a catalyst is inserted into the exhaust gas passage. However, if the exhaust gas purifier is arranged in the exhaust gas passage downstream of the gas-liquid heat exchanger, the above-mentioned problem occurs. Can not be solved, and when the exhaust gas purifier is arranged in the exhaust gas path upstream of the exhaust block, the temperature of the catalyst becomes high due to the high temperature exhaust gas,
Since the catalyst itself generates reaction heat by the reaction with the exhaust gas, there is a problem that the thermal deterioration is severe and the life of the catalyst is short.

The present invention has been made paying attention to such a point, and an object thereof is to effectively arrange an exhaust gas purifying tool.

<Means for Solving the Problems> In order to achieve the above object, the present invention provides a heat recovery device in which a gas-liquid heat exchanger is arranged above an exhaust block in which a cooling liquid chamber is formed. In, the exhaust gas purifying tool housing part is formed between the gas outlet port of the exhaust gas exhausting pipe and the gas inflow port of the gas-liquid heat exchanger, and the exhaust gas exhausting pipe is disposed through the exhaust gas purifying tool disposed in the exhaust gas purifying tool housing part. It is characterized in that the gas outlet of (1) and the gas inlet of the gas-liquid heat exchanger are communicated with each other.

<Operation> In the present invention, in the heat recovery device in which the gas-liquid heat exchanger is arranged above the exhaust block having the cooling liquid chamber formed therein, the gas outlet of the exhaust outlet pipe and the gas-liquid heat exchange. An exhaust gas purifying tool housing is formed between the gas inlet of the reactor and the gas outlet of the exhaust gas outlet pipe and the gas inlet of the gas-liquid heat exchanger via the exhaust gas purifying tool arranged in the exhaust gas purifying tool housing. The exhaust gas that has flowed into the exhaust gas purifier housing portion undergoes primary heat exchange with the cooling liquid in the cooling liquid chamber while flowing through the exhaust gas outlet pipe in the exhaust block, and the temperature drops. It is relatively low temperature. Therefore, the exhaust gas purifying tool such as the catalyst is not exposed to high heat.

<< Embodiment >> A drawing shows an embodiment of the present invention, and FIG.
FIG. 2 is a sectional view taken along line II-II in FIG.

In the figure, (1) is a heat recovery device, and this heat recovery device (1) includes an exhaust block (2) and an exhaust block (2).
And a spacer member (4) arranged between the gas / liquid heat exchanger (3) and the exhaust block (2).

The exhaust block (2) is formed so as to surround the exhaust outlet pipe (6), which is an exhaust manifold communicating with the exhaust port (5) of the engine body (E), and the outer peripheral portion of the exhaust outlet pipe (6). And a cooling liquid chamber (7)
Exhaust gas flowing in the exhaust gas outlet pipe (6) and cooling liquid chamber (7)
It acts as an auxiliary heat exchanger for exchanging heat with the cooling liquid flowing through. In addition, an exhaust gas passage (9) communicating with the muffler (8) is transparently provided outside the cooling liquid chamber (7) in the exhaust block (2).

The gas-liquid heat exchanger (3) is composed of a casing (11) forming a liquid chamber (10) for a heat transfer liquid, and a heat dissipation core (13) having an exhaust gas passage (12) inside. This heat dissipation core (13) is formed by stacking a number of flat oblong core units each having a hollow inside with vertical intervals at appropriate intervals, and connecting both end sides of each core unit to each other with a circular communication portion (14). A gas inlet (15) is formed at the lower end of one of the communication parts, and
A gas outlet (16) is formed at the lower end of the other communicating portion.

The spacer member (4) has an exhaust gas purifying tool (17) such as a catalyst.
An exhaust gas purifying tool accommodating portion (18) for housing the exhaust gas purifying tool accommodating portion (18),
And a cooling liquid passage (20) are formed, an exhaust gas purifying tool exchange port (21) is opened on the side surface of the spacer member (4), and the exhaust gas purifying tool exchange port (21) is formed by a cover plate (22). It is closed.

Then, the gas inlet (15) of the gas-liquid heat exchanger (3) is communicated with the exhaust outlet (23) of the exhaust outlet pipe (6) via the exhaust gas purifier housing section (18), and the gas outlet is provided. (16)
Is communicated with the exhaust gas passage (9) of the exhaust block (2) through the exhaust gas passage (19).

On the other hand, the cooling liquid chamber (7) in the exhaust block (2) and the liquid chamber (10) in the gas-liquid heat exchanger (3) are the spacer member (4).
Are communicated with each other via a cooling liquid passage (20), and a cooling liquid outlet (24) is formed on the upper wall of the casing (11) of the gas-liquid heat exchanger (3). A cooling liquid inlet (26) is provided on the side wall (25) of the exhaust block (2) on the side opposite to the engine body. This allows the coolant inlet (2
The cooling liquid that has flowed into the cooling liquid chamber (7) in the exhaust block (2) from 6) exchanges heat with the exhaust gas flowing in the exhaust outlet pipe (6), and then from the cooling liquid passage (20). Liquid chamber (10) in the gas-liquid heat exchanger (3) that flows into the heat exchanger (3)
The heat exchange with the exhaust gas flowing through the heat dissipation core (13) during the flow of the gas through the cooling liquid outlet (24).

With this structure, heat can be recovered by the cooling liquid flowing through the cooling liquid passage (20) via the spacer member (4). Further, the spacer member (4) is a cooling liquid passage (20).
The exhaust gas purifying tool (17) is heated by the heat of the spacer member (4) because it is heated by the heat of the coolant flowing through the exhaust gas purifying tool (17) due to the low engine load range. The temperature does not drop sharply.

FIG. 3 shows another embodiment of the present invention, in which an exhaust gas purifying tool accommodating portion (18) is integrally formed on a support base (27) of a heat dissipation core (13) in a gas-liquid heat exchanger (3). It was done.

<Effect> According to the present invention, in the heat recovery device in which the gas-liquid heat exchanger is arranged above the exhaust block having the cooling liquid chamber formed therein, the gas outlet of the exhaust outlet pipe and the gas-liquid heat exchange. An exhaust gas purifying tool housing is formed between the gas inlet of the reactor and the gas outlet of the exhaust gas outlet pipe and the gas inlet of the gas-liquid heat exchanger via the exhaust gas purifying tool arranged in the exhaust gas purifying tool housing. The exhaust gas that has flowed into the exhaust gas purifier housing portion undergoes primary heat exchange with the cooling liquid in the cooling liquid chamber while flowing through the exhaust gas outlet pipe in the exhaust block, and the temperature drops. It is relatively low temperature. Therefore, the exhaust gas purifying tool such as a catalyst is not exposed to high heat, and the reaction heat of the reaction of the exhaust gas purifying tool itself is recovered by the cooling liquid flowing from the cooling liquid chamber of the exhaust block to the liquid chamber of the gas-liquid heat exchanger. Therefore, the life of the exhaust gas purifying tool can be extended.

Further, since the exhaust gas purifying tool is arranged in the portion that connects the cooling liquid chamber of the exhaust block and the liquid chamber of the gas-liquid heat exchanger, the temperature of the exhaust gas purifying tool may suddenly change due to the engine load. It is possible to perform stable exhaust gas purification.

Furthermore, since the exhaust gas flowing into the gas-liquid heat exchanger becomes the gas after being purified by the exhaust gas purifier, the core part of the gas-liquid heat exchanger is not damaged by the harmful components in the exhaust gas. .

As a result, the exhaust gas purifying tool having a stable purifying ability can be arranged compactly and efficiently.

[Brief description of drawings]

The drawings show an embodiment of the present invention, and FIG. 1 is a longitudinal sectional view of an essential part,
2 is a sectional view taken along the line II-II in FIG. 1, and FIG. 3 is a view corresponding to FIG. 1 of another embodiment. E ... Engine body, 2 ... Exhaust block, 3 ... Gas-liquid heat exchanger, 5 ... (E) exhaust port, 6 ... Exhaust outlet pipe, 7 ... (2) Coolant chamber, 8 ...... Exhaust muffler, 10 ...
… (3) Liquid chamber, 15 …… (3) Gas inlet, 16 ……
(3) Gas outlet, 17 ... Exhaust gas purifier, 18 ... Exhaust gas purifier housing, 23 ... (6) Gas outlet.

Claims (1)

[Scope of utility model registration request] 1. An exhaust block (2) is formed by forming a cooling liquid chamber (7) on the outer circumference of an exhaust outlet pipe (6) connected to an exhaust port (5) of an engine body (E). A gas-liquid heat exchanger (3) is arranged above (2), and the gas outlet (23) of the exhaust outlet pipe (6) communicates with the gas inlet (15) of the gas-liquid heat exchanger (3). While connected, the gas outlet (16) of the gas-liquid heat exchanger (3) is communicated with the exhaust muffler (8), and the liquid chamber (10) of the gas-liquid heat exchanger (3) is connected to the exhaust block (2). In an exhaust heat recovery system for an engine, which communicates with a cooling liquid chamber (7), a gas outlet (23) of an exhaust outlet pipe (6) and a gas inlet (15) of a gas-liquid heat exchanger (3) are connected. An exhaust gas purifying tool accommodating portion (18) is formed between the exhaust gas purifying tool accommodating portion (18), and the gas is discharged from the exhaust gas exhausting pipe (6) through the exhaust gas purifying tool (17). Mouth (23) and gas inlet (1) of gas-liquid heat exchanger (3)
5) Exhaust heat recovery device for engine characterized by communicating with