JPS6090975A - Adiabatic engine - Google Patents

Abstract

PURPOSE:To contrive to increase the output of the engine by arranging an oxygen enriching device on the way of an air suction pipe to increase the rate of isochoric change in a combustion stroke and to contrive the smooth operation of the engine by opening a solenoid bypass valve when the air passing resistance of the oxygen enriching device became large. CONSTITUTION:The inner tube 38 and the outlet pipe 31a of the oxygen amplifier 30 are connected to the half way of the suction air pipe 11 connected to the suction port 10 of a cylinder head 2. Air, introduced into the inner tube 38 through the air suction pipe 11 from an air cleaner 12 in accordance with the operation of the engine, is introduced into the inner chamber through a through hole 36, then, is introduced into the outer chamber from here through a filter 32. The molecule of oxygen is passed through the filter 32 preferentially to increase the oxygen concentration, thereafter, the air is supplied into the combustion chamber 15 from an outlet pipe 31a through the suction air pipe 11. On the other hand, in case the air sucking resistance of the suction air pipe 11 is increased, the pressure drop of the outlet pipe 31a is detected by a pressure sensor 35, the solenoid bypass valve 34 is opened based on the signal and the amount of suction air may be increased.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an engine having a heat insulating structure using ceramics.

Ceramic materials are used on the walls that define 1g of the combustion chamber, such as the cylinder pipe, piston, and cylinder head, and the heat energy, which would normally be released to the outside by cooling water, is concentrated in the exhaust gas and sent to the exhaust turbine. An engine with an insulated Ti structure that returns the heat to the crankshaft has been proposed.

However, using an insulated WIJ structure for the 12i firing chamber raises the temperature of the wall of the combustion chamber, causing early ignition of the fuel injected from the injection nozzle, resulting in a decrease in the rate of pressure rise and a decrease in thermal efficiency. There is a risk that it will decline. In addition, there is a possibility that the intake efficiency decreases due to the increase in wall draft, and the average effective pressure decreases.

Therefore, in the case of an adiabatic engine, the output and fuel efficiency may be reduced.

To elaborate on this point, theoretically, the thermal cycle of a conventional cooling engine is shown in the tT-8 diagram (temperature -
In the entropy diagram), /MB-C=D' is expressed, whereas the thermal cycle of an adiabatic engine is expressed as ABCD. Here, Δ'B- represents a combustion stroke, B-C= an expansion stroke, CD' represents an intake/exhaust stroke, and D'A- represents a compression stroke. In an adiabatic engine represented by ABCD, point 8 is much higher than point B' due to the adiabatic effect during the combustion stroke, that is, the heat generation period, and it is thought that the amount of work will increase in an adiabatic engine than in a cooled engine. It will be done.

However, in actual control engines, things don't work out as expected in theory. In other words, the combustion stroke of the cooled engine is shown in Figure 2 as △-E.
As shown by 'B', equalize the volume with A-E-, and then E'-
8- causes an isobaric change, and the isovolume change A'E- is an isobaric change E-
The slope is steeper than B-. When the tendency of fuel ignition delay is large as in a cooled engine, the proportion of equal volume change Δ''E- increases and the proportion of equal pressure change BE- decreases.

On the other hand, in the thermal cycle of an adiabatic engine, as shown by the solid line AEBCD in Figure 2, the temperature of the combustion chamber is high, so
The ignition delay after fuel injection is shortened, and the proportion of volume equalization AE is reduced. As a result, the rate of isobaric change EB increases significantly, and the maximum moisture content is not much different from that of a conventional cooled engine. In this way, the heat generated by the engine 1iAEBCD increases the power of the adiabatic engine, but the output BC may actually become larger in the cold N1 engine.

As a result of the above, the thermal efficiency of an adiabatic engine may not change much or may even decrease compared to a cooled engine simply by making the combustion chamber adiabatic steel. In order to rapidly increase the heat release rate of an adiabatic engine, it is necessary to increase the proportion of volumetric AE in combustion, but this cannot be achieved by normal methods due to the characteristics of the fuel.

Therefore, an object of the present invention is to provide an adiabatic engine that can increase the rate of equalization of combustion in the adiabatic engine with a simple configuration.

For this reason, the configuration of the present invention is such that an oxygen enricher equipped with a filter such as a polyolefin membrane and a bypass valve is inserted and connected in the middle of the intake pipe, and a negative pressure sensor is installed downstream of the oxygen enricher in the intake pipe. The bypass valve is provided with a control device that opens the bypass valve when the negative pressure detected by the negative pressure sensor 9 falls below a predetermined value.

To explain the present invention based on an embodiment, as shown in FIG. 3, an engine includes a piston 4 fitted into a cylinder formed in a cylinder block 1, and a piston pin
A connecting rod 6 connected at 4 is connected to an arm of a crankshaft 7. The upper end of the cylinder block 1 is closed by a cylinder head 2, and a combustion chamber 15 is defined. An intake port 10 and an exhaust port 13 connected to the combustion chamber 15 are provided in the cylinder head 2, and are opened and closed by an intake valve 8 and a similar exhaust valve (not shown).

In the adiabatic engine, a cylinder liner 3 made of ceramics is fitted onto the inner wall surface of a cylinder block 1, and a headliner 9 made of ceramics is coupled to the inner wall surface of the cylinder head 2. Further, a piston liner 5 made of ceramics is coupled to the top end surface of the piston 4. Preferably, the intake valve 8 and the exhaust valve are also integrally constructed of ceramics.

In this way, the walls surrounding the combustion chamber 15 are all made of ceramics that have heat resistance and heat insulation properties, and are configured to minimize the heat of the combustion gas in the combustion chamber 15 from dissipating to the outside. be done.

According to the present invention, the oxygen enricher 30 is connected in the middle of the intake pipe 11 connected to the intake air 1'10. This oxygen enricher 30
As shown in Fig. 4.5, the inner 1ri 138 and the outer cylinder 31
A filter 32 made of a polyolefin film bent into a petal shape is arranged between the inner chamber 25 and the outer chamber 26.
and are divided. The outer cylinder 31 has both ends connected to end plates 39 and 4.
Closed by 1. The inner chamber 25 communicates with the inside of the inner cylinder 38 via a through hole 36 provided in the inner part 83B. On the other hand, the outer chamber 26 communicates with a hole 28 formed between the partition plate 40 and the end plate 41 through a through hole 37 provided in the partition plate 40 of the outer cylinder 31. Chamber 28 is connected to outlet ll31a. A pressure sensor 35 is provided on this outlet pipe 31a.

An electromagnetic piston valve 3 is installed at the end of the inner cylinder 38 which also serves as an inlet pipe.
4 is disposed and is normally pressed against the valve seat 34a by a spring 29 to close the inner end of the inward direction 38. The signal number of the pressure sensor 35 is added to the control device 20,
When the negative pressure in the intake pipe becomes lower than a predetermined value, the control device 2
The electromagnetic coil of the electromagnetic bypass valve 34 is excited by the output signal from 0, and the valve element is separated from the valve seat 34a. The filter 32 is overlapped and bonded to a metal reinforcing plate 33 having a large number of through holes.

In the oxygen enricher 30 configured as described above, the inner cylinder 38 and the outlet pipe 31a are connected to the middle of the intake air 1!11. As the engine operates, air is guided from the air cleaner 12 through the intake pipe 11 to the inner chamber 25 through the through hole 36, and from there passes through the filter 32 to the outer chamber 26.
Enter. Oxygen molecules pass through the filter 32 preferentially, increasing the oxygen concentration. Then, from the outer chamber 26, the through hole 37 enters the -C chamber 28, and then from the outlet pipe 31a to the intake pipe 1.
1 to the combustion chamber 15 of the cylinder.

Since the oxygen concentration of the intake air supplied to the combustion chamber 15 via the oxygen enricher 30 is greatly increased, the combustion rate increases and the rate of isovolume change in the combustion chamber increases. This means that the temperatures at points E and B shown in the ff12 diagram become higher, and the output BC increases significantly.

Further, in the combustion chamber 15, the heat of the combustion gas is minimized from being transferred from the wall of the combustion chamber to the outside, so that the heat is supplied from the exhaust port 13 to the exhaust turbine in a high temperature state. The power of the exhaust turbine is transmitted to the crankshaft 7 through a suitable means such as a gear Ia1fI. In this way, the kinetic energy of the piston 4 due to combustion and expansion of fuel in the combustion chamber 15 of the adiabatic engine is increased, and
Since exhaust gas is discharged in a high temperature state, if this thermal energy is recovered using an exhaust turbine or the like, a high recovery efficiency can be obtained.

When the intake resistance of the intake pipe 11 increases due to engine load fluctuations, the pressure sensor +135
A pressure drop is detected, and based on this signal, the electromagnetic bypass valve 34 is pulled away from the valve seat 34a against the spring 29, and the inner cylinder 38 is communicated with the outlet pipe 31a via the chamber 28. Therefore, in this case, the ventilation resistance of the filter 32 is eliminated, and the amount of intake air can be increased.

Note that even if the exhaust gas is supplied to an exhaust turbo supercharger to increase the 1τ intake efficiency, it is possible to increase the output and improve the thermal efficiency.

As described above, in the present invention, by disposing the oxygen enricher 30 in the middle of the intake pipe 11, the oxygen concentration of the intake air supplied to the combustion chamber 15 can be significantly increased. The speed is increased, the rate of isovolumic change in the combustion culms can be increased, and the power of the engine can be significantly increased.

In a normal cooled engine, lowering the oxygen concentration will increase the combustion rate, but it will also increase the heat load, which will exceed the heat resistance limits of pistons, cylinder liners, etc., resulting in seizures.

However, in the present invention, the combustion chamber is made of a heat-insulating VA structure and has sufficient durability, especially against high temperatures, which is useful for increasing output and, by extension, improving fuel efficiency. Furthermore, since the combustion chamber is maintained at a high temperature, combustion conditions are improved during low-speed, high-load operation, and smoke generation can be reduced. When the ventilation resistance of the oxygen enricher increases due to sudden acceleration or high-load operation of the engine, the electromagnetic bypass valve operates and reduces the resistance of the intake pipe, increasing the amount of intake air and ensuring smooth operating performance. You can get it.

[Brief explanation of the drawing]

Figure 1 is a theoretical l-s diagram comparing a general cooling engine and an adiabatic engine, and Figure 2 is the actual T-s diagram.
Figure 3 is a front cross-sectional view showing the schematic structure of the heat insulation engine according to the present invention, and Figure 4G is a side cross-sectional view of the oxygen enricher attached to the heat insulation engine. , and Fig. 5 is a front sectional view of the same. 3 Nijiliner liner 4: Piston 5: Piston liner 9: Herad liner 11: Intake pipe 12: Air cleaner 15: Combustion chamber 30: Oxygen enricher 32: Filter 34: Electromagnetic Pi!<Suben 35: Pressure sensor patent applicant IPzu Jidosha Co., Ltd. Patent attorney Toshio Yamamoto

Claims (1)

[Claims] An oxygen enricher equipped with a filter such as a polyolefin membrane and a bypass valve is inserted and connected in the middle of the intake pipe, and a negative pressure sensor is disposed downstream of the oxygen enricher in the intake pipe. An adiabatic engine comprising: a control device that opens the bypass valve when the negative pressure detected by the pressure sensor falls below a predetermined value.