JPH0545770Y2 - - Google Patents

Description

[Detailed explanation of the idea] 《Industrial application field》 The present invention relates to an engine exhaust heat recovery device.

<Prior art> As an engine exhaust heat recovery device, a heat radiation passage of an exhaust heat recovery device is interposed in the exhaust heat absorption circuit that absorbs engine exhaust heat, and a heat absorption passage of the exhaust heat recovery device is used for exhaust heat recovery. Generally, a pump is inserted in the exhaust heat recovery circuit in series with the heat absorption passage of the exhaust heat recovery device, and the pump circulates the exhaust heat recovery liquid within the exhaust heat recovery circuit. and
The pump for circulating the waste heat recovery liquid was driven by an electric motor, and its power source was a generator driven by the engine.

《Problem that the invention aims to solve》 However, although the conventional pump drive type has the advantage of being able to easily stop the pump when exhaust heat recovery is suspended, once the engine output is replaced with electric power, the pump cannot be stopped again. The drive efficiency of the pump was low because it was returned to mechanical power using an electric motor.

An object of the present invention is to improve the pump drive mode so that the pump can be operated with high efficiency while still being able to perform stop control in the same way as conventional pumps.

《Means for solving the problems》 The characteristic structure of the present invention to achieve the above purpose is as follows:
The pump is interlocked with the engine, an electric clutch is interposed in the pump transmission device that interlocks the pump with the engine, the electric clutch is configured to be controllable by the heat recovery control device, and the heat recovery stop output signal of the heat recovery control device is connected. Based on this, the circulation of the exhaust heat recovery liquid in the exhaust heat recovery circuit is stopped by interrupting the transmission of the electric clutch and stopping the pump.

<<Operation>> According to the above configuration, during normal exhaust heat recovery operation, the engine output can directly and efficiently drive the pump to circulate the exhaust heat recovery liquid. Furthermore, when exhaust heat recovery is suspended, the pump can be easily stopped by disengaging the electric clutch.

<<Example>> Hereinafter, an example of the present invention will be described based on the drawings.

Figure 1 shows the overall configuration of an engine generator equipped with an exhaust heat recovery device for a water-cooled horizontal engine according to the present invention.
Moreover, FIG. 2 shows a system diagram of each exhaust heat recovery device.

The engine generator shown in Fig. 1 has a soundproof case 1.
A generator G and a water-cooled horizontal engine E that drives the generator G with a belt are installed in parallel, a fuel tank 2 is installed on the ceiling wall of the soundproof case 1, and a transmission motor 3 is connected to one end of the soundproof case 1. The cooling fan 4 is provided with a radiator 5 equipped with a cooling fan 4 driven by the cooling fan 4.

An exhaust heat recovery device A according to the present invention is disposed above the engine E. First, the basic configuration of the exhaust heat recovery device A will be explained based on the system diagram shown in FIG.

After absorbing the combustion heat in the water jacket 6 formed in the engine E, the heat medium liquid (water) drawn out is transferred to the exhaust heat absorption circuit a, which is equipped with an exhaust heat absorber 7 and an exhaust heat recovery device 8 in series. sent to. The exhaust heat absorption circuit a includes a heat absorption passage b that absorbs heat through heat exchange with engine exhaust gas in the exhaust heat absorber 7;
In the exhaust heat recovery device 8, there is a heat radiation passage c that exchanges heat with the exhaust heat recovery liquid and radiates the heat, and the heat medium liquid that has passed through the exhaust heat absorption circuit a is cooled by the radiator 5, and then passes through the return circuit d. The water is forcibly returned to the water jacket 6 via the water pump 9.
A heat absorption passage f of an exhaust heat recovery circuit e for flowing an exhaust heat recovery liquid is interposed in the exhaust heat recovery device 8. It is configured to be forced to circulate through heat load devices such as equipment. Furthermore, the exhaust gas leaving the exhaust heat absorber 7 is discharged to the outside of the machine via a muffler 11.

Next, each part constituting the exhaust heat recovery device A will be explained in detail.

The exhaust heat absorber 7 is connected to the exhaust manifold 1 of the cylinder head 12, as shown in FIGS. 3 and 4.
A multi-plate heat exchanger 15 is connected to the engine E through an exhaust pipe 14, and a water tank 16 is directly connected to the upper surface of the crankcase of the engine E. The heat transfer liquid flows directly into the heat absorption passage b in the water tank 16.

The exhaust heat recovery device 8 is a water tank 18 that is bent and extended in an L shape from the water tank 16 of the exhaust heat absorber 7 and installed on the side of the cell starter 17.
A multi-tubular heat exchanger 19 that forms a heat absorption passage f for the exhaust heat recovery liquid is installed inside the tank, and an exhaust heat absorber 7 is installed at the corner formed by both water tanks 16 and 18. A muffler 11 is installed which is connected in communication with a heat exchanger 15.

Further, a heat medium liquid outlet 20 is provided on the upper surface of the water tank 18 that forms the heat radiation passage c of the exhaust heat recovery device 8, and this outlet 20 and the upper part of the radiator 5 are connected to each other by a hose 21.

The water pump 9 for forced circulation of the heat medium liquid is driven by the engine output provided in the cylinder head 12, and is connected to the intake port 22 and the radiator 5.
is connected to the lower part of the water jacket 6 by a hose 23, and a discharge port (not shown) is connected to the water jacket 6.
is connected directly to the bottom of the

A more detailed configuration of the exhaust heat recovery device 8 is shown in FIG. An inlet case 25 equipped with an inlet 24 for waste heat recovery liquid is attached to the rear end of the water tank 18 that forms a heat radiation passage c for the heat transfer liquid, and an inlet case 25 equipped with an inlet 24 for waste heat recovery liquid is attached to the front end of the water tank 18. pump 10 and the discharge port 26 of the pump 10
An outlet case 28 having an outlet 27 communicating with the outlet case 28 is attached, and the jackets of both the cases 25 and 28 are connected to each other by a shell-and-tube heat exchanger 19 forming a heat absorption passage f.

An input pulley 29 is connected to the pump 10 for receiving engine output through belt transmission, and an electric (electromagnetic) clutch 31 is interposed between the pulley 29 and a pump shaft 30.

The exhaust heat recovery device A according to the present invention is constructed as described above, and during normal exhaust heat recovery operation, the electric clutch 31 is engaged, the pump 10 is driven by the engine output, and the exhaust heat recovery liquid is discharged. It is circulated to the heat recovery circuit e.

Furthermore, when waste heat recovery becomes unnecessary due to a decrease in the load on the heat load device L, etc., a heat recovery stop output signal is issued from the heat recovery control device 32, and based on this, the electric clutch 31 automatically shuts off the transmission. The operation of the pump 10 is stopped.

<<Effects of the invention>> As explained above, in the engine exhaust heat recovery device according to the present invention, the pump that circulates the exhaust heat recovery liquid is directly driven by the engine output.
Compared to a configuration in which the pump is driven by an electric motor after it is converted into electric power, the pump drive efficiency is increased and running costs can be reduced.

Moreover, since the pump can be stopped and operated by an electric clutch, the operation of the pump can be electrically controlled in the same manner as in the past, and high performance can be maintained.

[Brief explanation of the drawing]

FIG. 1 is a rear view of an engine generator equipped with an exhaust heat recovery device according to the present invention, FIG. 2 is a schematic system diagram of the exhaust heat recovery device, FIG. 3 is a partially cutaway plan view of the engine section, and FIG. Figure 4 is a partially cutaway side view of the engine section.
FIG. 5 is a longitudinal sectional side view of the exhaust heat recovery device. 8... Exhaust heat recovery device, 10... Exhaust heat recovery liquid circulation pump, 31... Electric clutch, 32... Heat recovery control device, a... Exhaust heat absorption circuit, c... Heat radiation passage, e ...exhaust heat recovery circuit, f...heat absorption passage,
E...Engine.

Claims (1)

[Claims for Utility Model Registration] The heat radiation passage c of the exhaust heat recovery device 8 is interposed in the waste heat absorption circuit a that absorbs the waste heat of the engine E, and the heat absorption passage f of the waste heat recovery device 8 is used to exhaust heat. A pump 10 is interposed in the exhaust heat recovery circuit e in series with the heat absorption passage f of the exhaust heat recovery device 8,
In the engine exhaust heat recovery device configured to circulate the exhaust heat recovery liquid in the exhaust heat recovery circuit e using the pump 10, the pump 10 is interlocked with the engine E, and the pump 10 is interlocked with the engine E. An electric clutch 31 is interposed in the device, and the electric clutch 3
1 is configured to be controllable by a heat recovery control device 32, and the electric clutch 31 is disengaged based on the heat recovery stop output signal of the heat recovery control device 32 to stop the pump 10, thereby controlling the exhaust heat recovery circuit e. An exhaust heat recovery device for an engine, characterized in that it is configured to stop circulation of an exhaust heat recovery liquid inside the engine.