WO2003091565A1

WO2003091565A1 - Dme fuel feed device of diesel engine

Info

Publication number: WO2003091565A1
Application number: PCT/JP2003/005452
Authority: WO
Inventors: Shinya Nozaki; Toshifumi Noda; Yukihiro Hayasaka; Daijo Ushiyama
Original assignee: Bosch Automotive Systems Corporation
Priority date: 2002-04-26
Filing date: 2003-04-28
Publication date: 2003-11-06
Also published as: AU2003235959A1

Abstract

A DME fuel feed device of a diesel engine capable of feeding DME fuel from a fuel tank to the oil sump of an injection pump without using a drive means such as feed pump, wherein when an electric compressor (23) is turned on and a gaseous phase part (4b) in the fuel tank (4) is pressurized, the DME fuel in a liquid phase part (4a) is sent to a feed pipe (5), and then filled into the oil sump (11), an injection pipe (3), a nozzle return pipe (7), and a refrigerant feed pipe (51), the DME fuel fed as refrigerant is vaporized by a fuel carburetor (15) and sent to a fuel cooler (6) to cool the DME fuel filled in the oil sump (11) by the heat of the vaporization thereof, and the DME fuel in the fuel tank (4) is fed to the injection pump (1) due to a relative pressure difference between the cooled DME fuel in the oil sump (11) and the DME fuel in the fuel tank (4) caused by a temperature difference therebetween.

Description

Description DM ZELZENJINE's DME fuel supply system Technical field

The present invention relates to a DME fuel supply device for a diesel engine using DME (dimethyl ether) as a fuel, a DME fuel temperature control method in a DME fuel supply device for a diesel engine, and a DME fuel temperature control program. Background art

As a countermeasure against air pollution by diesel engines, attention has been paid to fuels that use DME (dimethyl ether), whose exhaust is clean, instead of light oil. DME fuel is a liquefied gas fuel, unlike light oil, which is the conventional fuel. In other words, DME has a property that it has a lower boiling point temperature than gas oil and, at atmospheric pressure, gas oil is liquid at room temperature while gas oil is liquid at room temperature. For example, in a diesel engine using DME as a fuel disclosed in Japanese Patent Application Publication No. 11-077871, the DME fuel supply device adds DME fuel in a fuel tank with a feed pump or the like. And send it to the injection pump. The injection pump pressure-feeds the DME fuel in the oil reservoir supplied from the fuel tank by a predetermined amount to each fuel injection nozzle of the diesel engine at a predetermined timing. Since DME fuel pressurized by the feed pump is continuously supplied to the oil reservoir of the injection pump, the DME fuel overflows so that the pressure of the DME fuel in the oil reservoir is kept constant. Returned to the feed tank. In other words, the DME fuel supplied from the fuel tank to the oil reservoir of the injection pump by a feed pump or the like is constantly circulating in a route passing from the fuel tank to the oil reservoir and the overflow fuel pipe.

In such a fuel circulation type DME fuel supply device, DME fuel is constantly circulated. Therefore, there is an advantage that the temperature distribution in the oil reservoir can be easily made uniform, thereby stabilizing the injection characteristics of each injection pump. Also, without controlling the pressure of the feed pump, the overflow provided in the overflow fuel pipe can be controlled.

—By controlling the amount of DME fuel that overflows with a valve, etc., the pressure of the DME fuel in the oil reservoir can be kept constant, thereby easily stabilizing the injection characteristics of each injection pump. There is a merit that it can be done. However, as described above, DME fuel has the property of becoming a gas at room temperature, and is vaporized when suctioned by a suction pump. Therefore, the feed pump for DME fuel needs to be pressurized and delivered by a mechanical pump such as a piston type. In addition, because DME fuel has low viscosity, it is inefficient to pressurize and send it out with a mechanical pump such as a piston type. Accordingly, a large-capacity pump is required as compared with a fuel supply system for a diesel engine of a light oil type, and there is a possibility that the cost is increased.

In addition, since the DME fuel is constantly circulating, for example, if a crack or the like occurs in the overflow fuel pipe, the overflowed DME fuel will continue to leak, and a large amount of DME fuel will leak. There is a possibility that it will be.

Furthermore, when the DME fuel remaining in the oil sump and the nozzle re-injection pipe of the fuel injection nozzle when the diesel engine is stopped is collected, the DME fuel remaining in the overflow fuel pipe must also be collected. After stopping the diesel engine, it may take a long time to recover the DME fuel remaining in the DME fuel supply system. Disclosure of the invention

The present invention has been made in view of such a situation, and the problem is to supply DME fuel from a fuel tank to an oil reservoir of an injection pump without using a driving means such as a feed pump. DME fuel supply for diesel engines To provide a location.

Another object is to provide a DME fuel supply device for a diesel engine that can obtain stable fuel injection characteristics of an injection pump.

In order to achieve the above object, a first aspect of the present invention is to provide a DME fuel supplied from a fuel tank via a feed pipe by a predetermined amount to a fuel injection nozzle of a diesel engine at a predetermined timing. An injection pump that sends out the fuel to the injection pipe, a nozzle return pipe that returns the DME fuel that overflows from the fuel injection nozzle to the feed pipe, and the DME in the oil sump of the injection pump. An oil sump fuel cooling device for cooling fuel, an oil sump fuel temperature detecting means for detecting a temperature of the DME fuel in the oil sump, and the oil sump fuel cooling device in the oil sump. The pressure between the oil reservoir and the fuel tank caused by adjusting the temperature of the DME fuel to be lower than the temperature of the DME fuel in the fuel tank. A DME fuel supply device for a diesel engine, wherein the DME fuel in the fuel tank is supplied to the oil reservoir according to a difference.

In the sump: As the DME fuel cools and the temperature of the DME fuel in the sump decreases, the saturated vapor pressure of the DME fuel in the sump decreases. Therefore, a differential pressure is generated between the saturated vapor pressure in the fuel tank and the saturated vapor pressure in the oil reservoir, which were substantially the same pressure at normal temperature, and the pressure difference caused the DME fuel in the fuel tank to reach the oil reservoir. It will be pumped. Further, the temperature of the DME fuel in the oil reservoir is detected by the oil reservoir fuel temperature detecting means, so that the pressure difference between the oil reservoir and the fuel tank is substantially constant. The DME fuel in the fuel tank can be pumped to the oil reservoir at a substantially constant pressure by controlling the temperature of the fuel tank with the oil reservoir fuel cooling device. Therefore, the hydraulic pressure of the DME fuel in the oil reservoir can be controlled to be substantially constant, whereby the injection characteristics of each injection pump can be stabilized.

Thereby, the DME fuel supply of the diesel engine according to the first aspect of the present invention is performed. According to the device, the DME fuel in the fuel tank can be pumped to the oil reservoir with a substantially constant force by the pressure difference between the saturated vapor pressure in the fuel tank and the saturated vapor pressure in the oil reservoir. Therefore, the operation and effect can be obtained in that DME fuel can be supplied from the fuel tank to the oil storage chamber without using a driving means such as a feed pump.

According to a second aspect of the present invention, in the first aspect, the oil reservoir fuel cooling device is configured to cool the DME fuel in the oil reservoir by a cooling cycle using the DME fuel as a refrigerant. A fuel cooler for cooling the DME fuel in the oil reservoir using heat of vaporization caused by the vaporization of the DME fuel. It is a fuel supply device.

As described above, DME fuel has the property of becoming a gas at room temperature, so it constitutes a cooling cycle using DME fuel as a refrigerant, and utilizes the heat of vaporization caused by the dME fuel escaping. To cool the DME fuel in the sump. In other words, since the DME fuel in the oil reservoir is cooled by the fuel cooler that effectively utilizes the excellent characteristics of the DME fuel as a refrigerant, the oil reservoir fuel cooling device can be rationally configured.

Thus, according to the DME fuel supply device for a diesel engine according to the second aspect of the present invention, in addition to the function and effect of the first aspect of the present invention, the excellent characteristics of the DME fuel as a refrigerant are effectively utilized. The fuel cooler described above can rationally configure the oil sump fuel cooling system, so that the effect of reducing the cost of the DME fuel supply system in Dzerjejing can be obtained.

According to a third aspect of the present invention, in the second aspect, the oil reservoir fuel cooling device comprises: a refrigerant supply pipe for supplying the DME fuel from the feed pipe; and a DME flowing through the refrigerant supply pipe. A fuel supply device for vaporizing fuel and sending it to the fuel cooler, and a solenoid valve for opening and closing the coolant supply pipe for opening and closing the coolant supply pipe, for controlling the opening and closing of the coolant supply pipe on / off solenoid valve A DME fuel supply device for a diesel engine, characterized in that it is controlled by the DME fuel supply system. In this way, by controlling the opening and closing of the refrigerant supply pipe opening and closing solenoid valve, the amount of the DME fuel that is sent to the fuel cooler can be controlled. Thereby, since the fuel cooler can be controlled, the temperature of the DME fuel in the oil reservoir by the oil reservoir fuel cooling device can be controlled.

Thereby, according to the DME fuel supply device of the diesel engine according to the third aspect of the present invention, the oil having a configuration capable of controlling the fuel cooler by controlling the opening / closing of the refrigerant supply pipe opening / closing solenoid valve. With the reservoir fuel cooling device, the above-described operation and effect according to the second aspect of the present invention can be obtained.

According to a fourth aspect of the present invention, in the third aspect, the DME fuel mixed in the lubricating oil in the cam chamber of the injection pump, which is a dedicated lubrication system separated from the lubrication system of the diesel engine, is separated. And an electric compressor that pressurizes the DME fuel separated at the oil separator and sends it to the fuel tank. The electric compressor is supplied from the refrigerant supply pipe to the oil reservoir fuel cooling device. The DME fuel supply device for a diesel engine, wherein the DME fuel is sent to the fuel tank by the electric compressor.

As described above, DME fuel has the property of becoming a gas at normal temperature, so in order to supply liquid DME fuel to the injection pump, the supply pressure to the injection pump must be higher than that of light oil fuel. There is a need to. Therefore, due to the high supply pressure to the injection pump, the fuel leaks into the injection pump's force chamber through the gap between the plunger and the plunger barrel of the injection pump that sends DME fuel to the fuel injection nozzle of the diesel engine. A problem arises in that the amount of fuel becomes larger than when light oil fuel is used. In addition, DME has a lower viscosity than light oil, so it easily leaks from gaps, and the amount of DME increases. Then, the DME fuel leaked from the gap between the plunger barrel and the plunger flows into the cam chamber of the injection pump and is deflected. Damaged: DME fuel may enter the crankcase of the diesel engine and ignite.

Therefore, the cam chamber is a dedicated lubrication system separated from the diesel engine lubrication system, the DME fuel mixed into the lubrication oil in the cam chamber is separated at the oil separator, and the separated DME fuel is pressurized by an electric compressor. By sending the fuel to the fuel tank, the risk of such a problem occurring can be reduced. Then, by using this electric compressor, the DME fuel supplied to the oil reservoir fuel cooling device from the refrigerant supply pipe is sent out to the fuel tank, so that the refrigerant can be used as a refrigerant without providing a dedicated refrigerant recovery means. Supplied to sump fuel cooling system: DME fuel can be recovered.

Thus, according to the DME fuel supply device for a diesel engine according to the fourth aspect of the present invention, in addition to the function and effect according to the second or third aspect of the present invention, without providing a dedicated refrigerant recovery means, Since the DME fuel supplied to the oil spill chamber fuel cooling device as a refrigerant can be recovered, the effect of lowering the cost of the oil spill chamber fuel cooling device can be obtained.

According to a fifth aspect of the present invention, there is provided the DME fuel supply device for a diesel engine according to the fourth aspect, further comprising a fuel tank temperature adjusting means for adjusting a temperature in the fuel tank. It is.

According to the DME fuel supply device for a diesel engine according to the fifth aspect of the present invention, in addition to the function and effect of the fourth aspect of the present invention, a fuel tank temperature adjusting means for adjusting the temperature in the fuel tank is provided. As a result, it is possible to control the temperature of the DME fuel in the oil reservoir to an optimum temperature while maintaining the relative temperature difference between the oil reservoir and the fuel tank. The function and effect of obtaining the fuel injection characteristics can be obtained.

According to a sixth aspect of the present invention, in the fifth aspect, in the fifth aspect, the fuel tank temperature adjusting means further comprises: A first return path which is sent to the fuel tank after being cooled and cooled, and the DME fuel sent from the electric compressor is sent to the fuel tank without passing through the air-cooled cooler. A second return path, a return path switching solenoid valve for switching between the first return path and the second return path, and a fuel tank temperature detecting means for detecting a temperature in the fuel tank. A DME fuel supply device for a diesel engine, characterized in that the DME fuel supply device is configured to control the temperature in the fuel tank by controlling the return path switching electromagnetic valve.

According to the DME fuel supply device for a diesel engine according to the sixth aspect of the present invention, the first return path through which the DME fuel sent from the electric compressor is cooled and then sent to the fuel tank, and the delivery from the electric compressor Controlling the temperature in the fuel tank by controlling a return path switching solenoid valve for switching the second return path in which the cooled DME fuel is sent to the fuel tank without being cooled. Thereby, the operation and effect according to the fifth aspect of the present invention described above can be obtained.

According to a seventh aspect of the present invention, in any one of the first to sixth aspects, after stopping the diesel engine, the oil remaining in the oil sump chamber of the injection pump and the nozzle line pipe after stopping the diesel engine. A diesel engine DME fuel supply device, comprising: a residual fuel recovery means capable of recovering DME fuel into the fuel tank.

If DME fuel remains in the injection system after the diesel engine stops, it leaks from the nozzle sheet of the fuel injection nozzle into the cylinder of the diesel engine, causing a danger. Fuel is full. As a result, abnormal combustion such as knocking may occur when starting the diesel engine, and the diesel engine may not start normally, generating large vibrations and noise. Therefore, after the diesel engine was stopped by the residual fuel recovery means, Also, by recovering the DME fuel remaining in the nozzle return pipe to the fuel tank, it is possible to reduce the risk of abnormal combustion such as knocking occurring when starting the diesel engine.

Thus, according to the diesel engine DME fuel supply device of the second aspect of the present invention, in addition to the operation and effect according to any one of the first to sixth aspects of the present invention, when starting the diesel engine, This has the effect of reducing the risk of abnormal combustion such as knocking that occurs in the vehicle.

In an eighth aspect of the present invention based on the seventh aspect, in the seventh aspect, the residual fuel recovery means includes: an inlet side of the oil reservoir communicating with the feed pipe; and a communication path of the nozzle return pipe, Communication path switching means for switching from the feed pipe to a residual fuel recovery pipe communicating with the inlet side of the electric compressor, the communication path switching means being provided in the oil reservoir chamber of the injection pump and in the nozzle return pipe. The DME fuel supply device for a diesel engine, wherein the DME fuel is configured to be recovered to the fuel tank by the electric compressor.

Thus, when the diesel engine is stopped, when the DME fuel remaining in the oil reservoir and the nozzle return pipe is recovered, the communication path between the oil reservoir and the nozzle return pipe communicating with the feed pipe is connected to the electric compressor. DME fuel remaining in the oil sump and the nozzle return pipe can be recovered by switching to the residual fuel recovery pipe communicating with one inlet side and driving the electric compressor.

Thereby, according to the DME fuel supply device of the diesel engine according to the eighth aspect of the present invention, the inlet side of the oil reservoir communicating with the feed pipe, and the communication path of the nozzle return pipe are connected to the feed pipe. The operation and effect according to the above-described seventh aspect of the present invention can be obtained by the communication path switching means for switching to the residual fuel recovery nozzle communicating with the inlet side of the electric compressor 1 from the fuel tank. According to a ninth aspect of the present invention, in the eighth aspect, the communication between the liquid phase portion of the fuel tank and the feed pipe is interrupted, and the gas phase portion of the fuel tank and the feed pipe are communicated. A gaseous phase fuel delivery means for delivering the gaseous DME fuel.

Since the gas phase of the fuel tank is filled with gaseous DME fuel that is higher in pressure than the oil reservoir, the communication between the liquid phase of the fuel tank and the feed pipe is cut off when diesel fuel is stopped. When the gas phase of the fuel tank communicates with the feed pipe, part of the fuel remaining in the feed pipe due to the pressure of the gas phase of the fuel tank is directed to the electric compressor via the refrigerant supply pipe. Can be extruded. Therefore, before recovering the DME fuel remaining in the oil reservoir and the nozzle cleaning pipe by the residual fuel recovery means, the DME fuel remaining in the feed pipe in advance by the gas-phase fuel delivery means is recovered. Since part of the fuel can be recovered to the fuel tank by the electric compressor, the feed pipe is filled with the depleted DME fuel, and the time required to recover the DME fuel by the residual fuel recovery means can be reduced. it can.

Thereby, according to the DME fuel supply device for a diesel engine according to the ninth aspect of the present invention, in addition to the operation and effect of the eighth aspect of the present invention, the time for collecting the DME fuel by the residual fuel recovery means is reduced. C In a tenth aspect of the present invention, in any of the first to ninth aspects, a capacity between the fuel tank and the feed pipe is larger than that of the fuel tank. When the diesel engine is started, communication between the fuel tank and the sub fuel tank is cut off, and a phase portion of the sub fuel tank and the electric compressor are connected to each other. By communicating with the outlet side, the DME fuel is supplied to the oil reservoir from the sub fuel tank whose gas phase is pressurized by the electric compressor. Forms a configuration, it is DM E fuel supply system for diesel engines, wherein. When starting the diesel engine, first, in the oil sump of the injection pump

DME fuel must be supplied, but initially there is no DME fuel in the oil reservoir, so the difference in hydraulic pressure between the oil reservoir and the fuel tank is used to transfer the DME fuel in the fuel tank to the oil reservoir. Cannot be sent to Therefore, the gas phase in the fuel tank is pressurized by driving the electric compressor, and the pressure in the liquid phase in the fuel tank is increased. Then, the DME fuel in the fuel tank pressurized by the electric compressor is sent out to the feed pipe by the pressure, and the DME fuel is charged into the oil reservoir.

However, it takes a certain amount of time to pressurize the large-capacity fuel tank with an electric compressor, so it takes a long time to fill the oil reservoir with DME fuel when starting diesel engines. There is a possibility that it will be done. Therefore, a sub fuel tank with a smaller capacity than the fuel tank is installed between the fuel tank and the feed pipe. When the DME fuel is filled into the oil reservoir when the diesel engine is started, the communication between the fuel tank and the sub fuel tank is cut off, and the gas phase of the sub fuel tank and the electric compressor By communicating with the outlet side, DME fuel is supplied to the oil reservoir from the sub fuel tank whose gas phase is pressurized by the electric compressor. Since the capacity of the sub fuel tank is smaller than that of the fuel tank, the pressurization time by the electric compressor can be shortened, so that the time required to fill the oil reservoir with the DME fuel by the pressure of the electric compressor can be shortened. You.

Thus, according to the DME fuel supply device for a diesel engine according to the tenth aspect of the present invention, in addition to the operation and effect according to any one of the first to ninth aspects of the present invention, at the time of starting the diesel engine, When filling DME fuel into the oil reservoir, the electric compressor pressurizes the inside of the sub fuel tank, which has a smaller capacity than the fuel tank provided between the fuel tank and the feed pipe. Since the DME fuel in the tank is filled into the oil sump, the time for filling the DME fuel into the oil sump can be reduced. The effect of being able to obtain is obtained.

According to a eleventh aspect of the present invention, in any one of the first to tenth aspects, the DME fuel delivered from the injection pump is supplied to a common rail, and is delivered from the common rail to each fuel injection nozzle. This is a diesel engine DME fuel supply device that has the following features.

According to the DME fuel supply device for a diesel engine according to the eleventh aspect of the present invention, in the DME fuel supply device for a common rail diesel engine, any one of the first to tenth aspects of the present invention described above The operation and effect of the present invention can be obtained. In order to achieve the above object, a first aspect of the present invention relates to a fuel injection nozzle for a diesel engine which supplies DME fuel supplied from a fuel tank via a feed pipe by a predetermined amount at a predetermined timing. An injection pump for delivering to an injection pipe communicating with the fuel injection nozzle, a nozzle return pipe for returning the DME fuel overflowing from the fuel injection nozzle to the feed pipe, and a cam for the injection pump An oil sump fuel cooling means for cooling the DME fuel in the oil sump of the injection pump by cooling a room; and an oil sump fuel temperature detecting means for detecting a temperature of the DME fuel in the oil sump. Adjusting the temperature of the DME fuel in the oil reservoir to a temperature lower than the temperature of the DME fuel in the fuel tank by the oil reservoir fuel cooling means. A DME fuel supply device for a diesel engine, characterized in that the DME fuel in the fuel reservoir is supplied to the oil reservoir by a pressure difference between the oil reservoir and the fuel tank. is there. Cooling the cam chamber of the injection pump cools the DME fuel in the oil chamber, and when the temperature of the DME fuel in the oil chamber decreases, the saturated vapor pressure of the DME fuel in the oil chamber decreases. It is going down. Therefore, a differential pressure occurs between the saturated vapor pressure in the fuel tank, which was approximately the same at room temperature, and the saturated vapor pressure in the oil reservoir, and the pressure difference causes the DME fuel in the fuel tank to be pumped to the oil reservoir. Will be done. In addition, the temperature of the DME fuel in the oil chamber is detected by the oil chamber fuel temperature detecting means, and the fuel chamber and the fuel are detected. By controlling the temperature of the DME fuel in the oil sump by the oil sump fuel cooling means so that the pressure difference between the tank and the tank becomes substantially constant, the DME fuel in the fuel tank is held at a substantially constant pressure. It can be pumped to the oil sump. Therefore, the hydraulic pressure of the DME fuel in the oil reservoir can be controlled to be substantially constant, whereby the injection characteristics of each injection pump can be stabilized.

Thus, according to the DME fuel supply device for a diesel engine according to the twelfth aspect of the present invention, the fuel tank is provided by the pressure difference between the saturated vapor pressure in the fuel tank and the saturated vapor pressure in the oil reservoir. Because the DME fuel inside the pump can be pumped to the oil reservoir at a substantially constant pressure, the DME fuel can be supplied from the fuel tank to the oil reservoir without using a driving means such as a feed pump. The effect is obtained.

According to a thirteenth aspect of the present invention, in the twelfth aspect, the oil reservoir fuel cooling means cools the cam chamber using heat of vaporization caused by vaporization of the DME fuel. The DME fuel supply system for diesel engines is characterized in that:

As described above, DME fuel has the property of becoming a gas at normal temperature, so it constitutes a cooling cycle using DME fuel as a refrigerant and utilizes the heat of vaporization caused by the vaporization of DME fuel. The cam chamber can be cooled, and the DME fuel in the oil chamber can be cooled. That is, since the DME fuel in the oil reservoir is cooled by effectively utilizing the excellent characteristics of the DME fuel as a refrigerant, the oil reservoir fuel cooling means can be rationally configured.

Thus, according to the DME fuel supply device for a diesel engine according to the thirteenth aspect of the present invention, in addition to the operational effects according to the first and second aspects of the present invention, excellent characteristics of the DME fuel as a refrigerant are provided. By effectively utilizing the oil reservoir, the oil reservoir fuel cooling means can be configured rationally, and the effect of reducing the cost of the DME fuel supply device for the diesel engine can be obtained.

According to a fifteenth aspect of the present invention, in the thirteenth aspect, the oil reservoir fuel cooling means comprises: A refrigerant supply pipe for supplying the DME fuel from the feed pipe; a fuel supply unit for supplying the DME fuel flowing to the refrigerant supply pipe to discharge the DME fuel into the cam chamber; A DME fuel supply device for a diesel engine, comprising: a refrigerant supply pipe opening / closing solenoid valve for opening / closing the coolant supply pipe, and being controlled by opening / closing the coolant supply pipe opening / closing solenoid valve. It is.

Thus, by controlling the opening and closing of the refrigerant supply pipe opening and closing solenoid valve, the amount of vaporized DME fuel discharged into the cam chamber can be controlled. Thereby, since the fuel vaporizer can be controlled, the temperature of the DME fuel in the oil reservoir by the oil reservoir fuel cooling means can be controlled.

Thus, according to the DME fuel supply device for a diesel engine according to the fourteenth aspect of the present invention, the DME fuel is discharged into the cam chamber by opening and closing the refrigerant supply pipe opening and closing electromagnetic valve. The operation and effect according to the above-described thirteenth aspect of the present invention can be obtained by the oil reservoir fuel cooling means having a configuration capable of controlling the fuel gasifier.

According to a fifteenth aspect of the present invention, in the fourteenth aspect, the DME fuel is mixed with lubricating oil in the power chamber, which is a dedicated lubrication system separated from the lubrication system of the diesel engine. A DME fuel supply device for a diesel engine, comprising: an oil separator that performs an oil separation, and an electric compressor that pressurizes the DME fuel separated by the oil separator and sends the pressurized DME fuel to the fuel tank. . As described above, DME fuel has the property of becoming a gas at normal temperature, so in order to supply liquid DME fuel to the injection pump, the supply pressure to the injection pump must be higher than that of light oil fuel. There is a need to. For this reason, the injection pump pumps the injection pump through the gap between the plunger barrel and the plunger of the injection pump that sends DME fuel to the fuel injection nozzle of the diesel pump due to the high pressure and supply pressure to the injection pump. This causes a problem that the amount of fuel leaking into the cam chamber becomes larger than when gas oil fuel is used. Also, Since DME has a lower viscosity than light oil, it easily leaks from gaps, and the amount of DME increases. Then, the DME fuel leaked from the gap between the plunger barrel and the plunger flows into the power chamber of the injection pump and is deflected, and the deflected DME fuel enters the diesel engine crank chamber and ignites. It may cause

Therefore, the cam chamber is a dedicated lubrication system separated from the lubrication system of the diesel engine, the DME fuel mixed into the lubricating oil in the cam chamber is separated in an oil separator, and the separated DME fuel is pressurized by an electric compressor. By sending the fuel to the fuel tank, the risk of such a problem occurring can be reduced. Then, DME fuel supplied from the refrigerant supply pipe to the oil reservoir fuel cooling means and discharged as a refrigerant into the cam chamber can be recovered to the fuel tank, thereby eliminating the need for a dedicated refrigerant recovery means. However, the DME fuel supplied to the oil reservoir fuel cooling means as a refrigerant can be recovered.

Thus, according to the DME fuel supply device for a diesel engine according to the fifteenth aspect of the present invention, in addition to the function and effect of the fourteenth aspect of the present invention, a dedicated refrigerant recovery means is provided. In addition, since the DME fuel discharged into the cam chamber as the refrigerant can be recovered, the effect of being able to configure the oil reservoir fuel cooling means at lower cost can be obtained.

A sixteenth aspect of the present invention is the DME fuel supply device for a diesel engine according to the fifteenth aspect, further comprising a fuel tank temperature adjusting means for adjusting the temperature in the fuel tank. It is.

According to the DME fuel supply device of the diesel engine according to the sixteenth aspect of the present invention, in addition to the operation and effect according to the fifteenth aspect of the present invention, the temperature in the fuel tank for adjusting the temperature in the fuel tank is increased. The adjusting means can control the temperature of the DME fuel in the oil reservoir to an optimum temperature while maintaining the relative temperature difference between the oil reservoir and the fuel tank. ME fuel injection characteristics can be obtained The operation and effect are obtained.

According to a seventeenth aspect of the present invention, in the sixteenth aspect, the fuel tank temperature adjusting means is configured such that the DME fuel delivered from the electric compressor is cooled via an air-cooled cooler, A second return path for sending out to the fuel tank, and a second return path for sending out the DME fuel sent from the electric compressor to the fuel tank without passing through the air-cooled cooler A return path switching solenoid valve for switching between the first return path and the second return path, and a fuel tank temperature detecting means for detecting a temperature in the fuel tank. A DME fuel supply device for a diesel engine, characterized in that the DME fuel supply device is configured to control the temperature in the fuel tank by controlling the return path switching electromagnetic valve.

According to the DME fuel supply device for a diesel engine according to the seventeenth aspect of the present invention, the DME fuel sent from the electric compressor is cooled and then sent to the fuel tank, the 12th return path, and the electric compressor. Control the temperature inside the fuel tank by controlling the solenoid valve that switches the return path that switches between the DME fuel sent from the fuel tank and the second return path that is sent to the fuel tank without cooling. Accordingly, the operation and effect according to the above-described sixteenth aspect of the present invention can be obtained.

An eighteenth aspect of the present invention is the aspect according to any one of the twelfth to seventeenth aspects, wherein the residual fuel remains in the oil reservoir of the ejection pump and in the nozzle return pipe after stopping the diesel engine. A DME fuel supply device for a diesel engine, comprising: a residual fuel recovery means capable of recovering the DME fuel used in the fuel tank.

If DME fuel remains in the injection system after the diesel engine stops, it leaks from the nozzle seat of the fuel injection nozzle into the cylinder of the diesel engine and vaporizes, and the cylinder is filled with vaporized DME fuel. According to that, When starting the engine, abnormal combustion such as knocking may occur, and the diesel engine may not start normally, causing large vibration and noise. Therefore, by using residual fuel recovery means, after stopping diesel fuel, DME fuel remaining in the oil sump chamber of the injection pump and in the nozzle return pipe is recovered to the fuel tank, so that such a diesel engine can be used. It is possible to reduce the risk of abnormal combustion such as knocking occurring at the time of starting.

Thus, according to the DME fuel supply device for a diesel engine according to the eighteenth aspect of the present invention, in addition to the operation and effect according to any one of the first to seventeenth aspects of the present invention, a diesel engine is provided. The operation and effect of reducing the risk of abnormal combustion such as knocking occurring at the time of starting can be obtained.

According to a nineteenth aspect of the present invention, in the eighteenth aspect, the residual fuel recovery means includes: an inlet side of the oil reservoir that communicates with the feed pipe; and a communication path of the nozzle re-opening pipe. A communication path switching means for switching from the feed pipe to the residual fuel recovery pipe communicating with the inlet side of the electric compressor, the oil reservoir of the induction pump, and the nozzle cleaning pipe. The DME fuel remaining in the DME fuel supply device for a diesel engine, wherein the DME fuel is recovered to the fuel tank by the electric compressor.

As described above, when the diesel engine is stopped, when the DME fuel remaining in the oil reservoir and the nozzle return pipe is recovered, the communication path between the oil reservoir and the nozzle return pipe communicating with the feed pipe is electrically driven. By switching to the residual fuel recovery pipe communicating with the inlet side of the compressor and driving the electric compressor, it is possible to recover the DME fuel remaining in the oil reservoir and the nozzle cleaning pipe.

Thus, according to the DME fuel supply device for a diesel engine according to the nineteenth aspect of the present invention, the inlet side of the oil reservoir communicating with the feed pipe, and the nozzle hole By the communication path switching means for switching the communication path of the turn pipe from the feed pipe to the residual fuel recovery pipe communicating with the inlet side of the electric compressor 1, it is possible to obtain the above-described operation and effect according to the eighteenth aspect of the present invention. it can.

According to a 20th aspect of the present invention, in the 19th aspect, communication between the liquid phase portion of the fuel tank and the feed pipe is interrupted, and communication between the gas phase portion of the fuel tank and the feed pipe is performed. A DME fuel supply device for a diesel engine, further comprising gas-phase fuel delivery means for delivering the gaseous DME fuel. Since the gas phase of the fuel tank is filled with gaseous DME fuel that is higher in pressure than the oil reservoir, the communication between the liquid phase of the fuel tank and the feed pipe is cut off when diesel fuel is stopped. When the gas phase of the fuel tank communicates with the feed pipe, part of the fuel remaining in the feed pipe due to the pressure in the gas phase of the fuel tank is directed to the electric compressor via the refrigerant supply pipe. Can be pushed out. Therefore, before the DME fuel remaining in the oil reservoir and the nozzle return pipe is recovered by the residual fuel recovery means, the DME fuel remaining in the feed pipe in advance by the gas-phase fuel delivery means is recovered. Since a part of the fuel can be recovered to the fuel tank by the electric compressor, the feed pipe is filled with vaporized DME fuel, and the time required to recover the DME fuel by the residual fuel recovery means can be reduced. .

Thereby, according to the DME fuel supply device for a diesel engine according to the twenty-fifth aspect of the present invention, in addition to the operation and effect of the nineteenth aspect of the present invention, the DME fuel recovery by the residual fuel recovery means The effect that the time can be shortened is obtained.

According to a twenty-first aspect of the present invention, in any one of the twenty-second to twenty-second aspects, a sub-fuel tank having a smaller capacity than the fuel tank is provided between the fuel tank and the feed pipe. When the diesel engine is started, the communication between the fuel tank and the sub fuel tank is cut off and the sub fuel tank is disconnected. By communicating the gas phase of the compressor with the outlet side of the electric compressor, the DME fuel is supplied to the oil reservoir from the sub-fuel tank whose gas phase is pressurized by the electric compressor. A DME fuel supply device for a diesel engine, characterized in that it is supplied to a diesel engine.

When starting a diesel engine, DME fuel must first be supplied to the oil sump of the injection pump, but initially there is no DME fuel in the oil sump, so there is a difference in hydraulic pressure between the oil sump and the fuel tank. The DME fuel in the fuel tank cannot be delivered to the oil sump using the fuel tank. Therefore, the gas phase in the fuel tank is pressurized by driving the electric compressor, and the pressure in the liquid phase in the fuel tank is increased. Then, the DME fuel in the fuel tank pressurized by the electric compressor is sent out to the feed pipe by the pressure, and the DME fuel is charged into the oil reservoir.

However, it takes a certain amount of time to pressurize the large-capacity fuel tank with the electric compressor.Therefore, it takes a long time to fill the oil reservoir with DME fuel when the diesel engine starts. May be caused. Therefore, a sub-fuel tank with a smaller capacity than the fuel tank is installed between the fuel tank and the feed pipe. When the DME fuel is filled into the oil reservoir when the diesel engine is started, the communication between the fuel tank and the sub fuel tank is cut off, and the gas phase of the sub fuel tank and the outlet of the electric compressor are shut off. The DME fuel is supplied to the oil reservoir from the sub fuel tank whose gas phase is pressurized by the electric compressor by communicating with the oil side. Since the capacity of the sub fuel tank is smaller than that of the fuel tank, the pressurization time by the electric compressor can be shortened, so that the time required to fill the oil reservoir with the DME fuel by the pressure of the electric compressor can be reduced. You.

Thus, according to the DME fuel supply device for a diesel engine according to the twenty-first aspect of the present invention, in addition to the effects of any one of the first to twenty-second aspects of the present invention, When filling the oil reservoir with DME fuel at the start of the diesel engine, the electric compressor pressurizes the inside of the sub fuel tank, which has a smaller capacity than the fuel tank provided between the fuel tank and the feed pipe. Since the DME fuel in the sub fuel tank is filled into the oil reservoir, the operation and effect of shortening the time for filling the DME fuel into the oil reservoir can be obtained.

According to a twenty-second aspect of the present invention, in any one of the twelfth to twenty-first aspects, the DME fuel delivered from the injection pump is supplied to a common rail, and from the common rail to each fuel injection nozzle. This is a DME fuel supply system for diesel engines, characterized in that it is delivered.

According to the DME fuel supply device for a diesel engine according to the twenty-second aspect of the present invention, in the DME fuel supply device for a common rail diesel engine, any one of the above-described first to twenty-second aspects of the present invention is provided. The operation and effect of the present invention can be obtained. The DME fuel temperature control method according to the twenty-third aspect of the present invention is characterized in that the DME fuel supplied from the fuel tank via the feed pipe is supplied to the fuel injection nozzle of the diesel engine by a predetermined amount at a predetermined timing. An injection pump for delivering to the connected injection pipe; an oil sump fuel temperature adjusting means for adjusting the temperature of the DME fuel filled in the oil sump of the injection pump; and the fuel A method for controlling the temperature of DME fuel in a DME fuel supply device for a diesel engine, comprising: a fuel evening temperature control means for adjusting the temperature of the DME fuel in the oil reservoir. as temperature becomes the specified temperature T _G, controls the oil reservoir chamber fuel temperature adjusting means, and the temperature of the D ME fuel in the oil reservoir chamber in front Symbol fuel evening links than the temperature of the D ME fuel relative To as a high temperature at a substantially constant temperature difference, controls the fuel evening links the temperature adjusting means, it is characterized in.

As described above, by controlling the oil reservoir fuel temperature control means so that the temperature of the DME fuel in the oil reservoir becomes the specified temperature T _Q , it is easily affected by the temperature change sent from the injection pump to the fuel injection nozzle. DME fuel temperature is kept almost constant Can be controlled. Therefore, the fuel injection characteristics of each fuel injection nozzle can be stabilized. Also, by controlling the temperature control means in the fuel tank so that the temperature of the DME fuel in the fuel tank becomes relatively higher than the temperature of the DME fuel in the oil reservoir with a relatively constant temperature difference, the temperature difference is controlled. DME fuel in the fuel tank can be pumped by the pressure difference of the saturated vapor pressure generated between the oil reservoir and the fuel tank.

The specified temperature _TG is a temperature at which the DME fuel injection characteristics of each fuel injection nozzle are most stable, and the fuel tank is set so that a pressure difference capable of pumping the DME fuel in the fuel tank occurs. The temperature is set to a temperature sufficiently lower than the upper limit temperature, and the optimum temperature obtained by experiments is set.

Thus, according to the temperature control method for the DME fuel according to the twenty-third aspect of the present invention, the DME fuel is supplied from the fuel tank to the oil reservoir of the injection pump without using a driving means such as a feed pump. It is possible to obtain the effect of obtaining stable fuel injection characteristics of the injection pump.

According to a twenty-fourth aspect of the present invention, in the twenty-third aspect, the oil reservoir fuel temperature adjusting means cools the DME fuel in the oil reservoir using the depleted DME fuel as a cooling medium. An oil sump fuel cooler, cooling medium supply means for supplying the DME fuel in the fuel tank as a cooling medium to the oil sump fuel cooler, and detecting a temperature of the DME fuel in the oil sump. And a temperature of the DME fuel in the oil reservoir based on the temperature of the DME fuel in the oil reservoir detected by the oil reservoir fuel temperature detector. defined as the temperature T _sigma, it said to 〇 New / 0 FF controlling supply operation of said cold却媒body by the cooling medium supply means, that is a temperature control method for a D ME fuel characterized by.

Thus, based on the temperature detected by the oil reservoir fuel temperature detecting means for detecting the temperature of the DME fuel in the oil reservoir, the temperature of the DME fuel in the oil reservoir becomes the specified temperature so that the temperature of the DME fuel in the oil reservoir becomes the specified temperature. Cooling medium to oil sump fuel cooler cooling DME fuel ON ZOFF control of the supply operation. In other words, based on the temperature of the DME fuel in the oil sump detected by the oil sump fuel temperature detection means, the cooling operation of the oil sump fuel cooler is ON / OFF controlled to cool the DME fuel in the oil sump. or, by repeating the or not cooled and controlled so that the temperature of DME fuel in the oil reservoir chamber is defined temperature T _alpha. As a result, the temperature of the DΜ fuel in the oil reservoir that rises due to heat from the diesel engine or the like can be maintained at the specified temperature _TG .

Thus, according to the DΜ fuel temperature control method according to the twenty-fourth aspect of the present invention, based on the temperature of the D の fuel in the oil reservoir detected by the oil reservoir fuel temperature detecting means. By controlling the supply operation of the cooling medium to the oil reservoir fuel cooler that cools the fuel in the oil reservoir, the operation and effect according to the twenty-third aspect of the present invention can be obtained.

According to a twenty-fifth aspect of the present invention, in the twenty-third aspect, the oil reservoir fuel temperature adjusting means includes an oil for cooling the DME fuel in the oil reservoir using the vaporized DME fuel as a cooling medium. A reservoir fuel cooler; a cooling medium supply means for supplying the DME fuel in the fuel tank as a cooling medium to the oil reservoir fuel cooler; and an oil for detecting the temperature of the DME fuel in the oil reservoir. A reservoir temperature detecting means for detecting a temperature of the DME fuel in the oil reservoir based on the temperature of the DME fuel in the reservoir detected by the fuel temperature detector. A method for controlling the temperature of a DME fuel, characterized by adjusting a supply amount of the cooling medium by the cooling medium supply means so that と_σ is obtained. As described above, the temperature of the DΜ fuel in the oil reservoir is adjusted to the specified temperature TG based on the temperature detected by the oil temperature fuel detecting means for detecting the temperature of the D の fuel in the oil reservoir. Adjust the amount of cooling medium supplied to the oil reservoir fuel cooler that cools the fuel in the oil reservoir. In other words, by adjusting the cooling power of the oil sump fuel cooler based on the temperature of the DME fuel in the oil sump detected by the oil sump fuel temperature detection means, the D Μ の fuel in the oil sump is controlled. Control so that the temperature becomes the specified temperature _TG . As a result, the temperature of the DME fuel in the oil sump, which rises due to heat from diesel engines, etc. The temperature can be maintained at the specified temperature _TG .

Thus, according to the DME fuel temperature control method according to the twenty-fifth aspect of the present invention, the DME fuel temperature in the oil reservoir is detected based on the DME fuel temperature in the oil reservoir detected by the oil reservoir fuel temperature detecting means. By controlling the supply amount of the cooling medium to the oil reservoir fuel cooler that cools the ME fuel, the operation and effect according to the twenty-third aspect of the present invention can be obtained.

According to a twenty-sixth aspect of the present invention, in the twenty-fifth aspect, the cooling medium supply unit adjusts a supply amount of the cooling medium to the oil sump fuel cooler according to a rotation speed of a rotary driving force source. and forms a structure to increase or decrease based on the temperature of DME fuel in the oil reservoir chamber detected by the oil reservoir chamber fuel temperature detecting means, and temperature the predetermined temperature T _e of the DME fuel in the oil reservoir chamber Thus, a method for controlling the temperature of the DME fuel, comprising controlling the number of rotations of the rotary driving force source.

According to the DME fuel temperature control method according to the twenty-sixth aspect of the present invention, the DME fuel in the oil reservoir is detected based on the temperature of the DME fuel in the oil reservoir detected by the oil reservoir fuel temperature detecting means. By controlling the number of rotations of the rotational driving force source of the cooling medium supply means so that the temperature of the fuel reaches the specified temperature T _Q , the supply amount of the cooling medium to the oil reservoir fuel cooler can be controlled. Thereby, the operation and effect according to the twenty-fifth aspect of the present invention can be obtained.

According to a twenty-seventh aspect of the present invention, in any one of the twenty-third to the twenty-sixth aspects, the fuel tank internal temperature control means is configured to control the temperature of the DME fuel delivered to the fuel tank via an air-cooled cooler. A first recirculation path that is cooled and then returned to the fuel tank, and a second path where the DME fuel delivered to the fuel tank is returned to the fuel tank without passing through the air-cooled cooler. (2) a return path switching means for switching between the first return path and the second return path; and a fuel tank fuel temperature for detecting a temperature of the DME fuel in the fuel tank. Detecting means for detecting the temperature of DME fuel in the fuel tank detected by the fuel tank fuel temperature detecting means. Controlling the return path switching means such that the temperature of the DME fuel in the fuel tank becomes relatively higher than the temperature of the DME fuel in the oil reservoir with a relatively substantially constant temperature difference. This is a method for controlling the temperature of DME fuel.

The first return path is to return to the fuel tank while the DME fuel sent to the fuel tank is cooled via the air-cooled cooler, while the second return path is to the fuel tank. The delivered DME fuel is returned to the fuel tank without passing through the air-cooled cooler, that is, without being cooled. Therefore, when returning the DME fuel to the diesel engine, the oil reservoir detected by the oil reservoir fuel temperature detecting means determines whether to return via the first return path or the second return path. By switching based on the temperature of the DME fuel in the oil reservoir and the temperature of the DME fuel in the fuel reservoir detected by the fuel reservoir in the fuel reservoir, the fuel tank is switched from the temperature of the DME fuel in the oil reservoir. The temperature of the DME fuel in the fuel tank can be controlled such that the temperature of the DME fuel in the fuel tank becomes high with a relatively constant temperature difference.

Thus, according to the DME fuel temperature control method according to the twenty-seventh aspect of the present invention, the temperature of the DME fuel in the oil reservoir and the fuel tank fuel temperature detected by the oil reservoir fuel temperature detecting means are detected. By controlling the DME fuel in the fuel tank by switching the return path of the DME fuel delivered to the fuel tank based on the temperature of the DME fuel in the fuel tank detected by the means, The operation and effect according to any one of the embodiments 23 to 26 can be obtained. ,

A DME fuel supply device for a diesel engine according to a twenty-eighth aspect of the present invention is configured to supply DME fuel supplied from a fuel tank via a feed pipe by a predetermined amount at a predetermined timing. An injection pump for delivering to an injection pipe communicating with a fuel injection nozzle; an oil reservoir fuel temperature adjusting means for adjusting a temperature of DME fuel filled in an oil reservoir of the injection pump; A fuel tank temperature control means for controlling the temperature of the DME fuel in the fuel tank; and a fuel tank temperature control means and the fuel tank temperature control means. A DME fuel supply device for a diesel engine equipped with a DME fuel temperature control means for control, the D ME fuel temperature control means, as temperature of the D ME fuel in the oil reservoir chamber is defined temperature T _alpha Controlling the oil reservoir fuel temperature adjusting means, and making the temperature of the fuel in the fuel tank relatively lower than the temperature of the fuel in the oil reservoir with a substantially constant temperature difference. The fuel tank temperature control means is controlled so that the temperature becomes high.

According to the D エンジン fuel supply device for a diesel engine according to the twenty-eighth aspect of the present invention, in the DME fuel supply device for a diesel engine, the same operation and effect as those of the above-described twenty-third aspect of the present invention can be obtained. Can be.

According to a twentieth aspect of the present invention, in the twenty-eighth aspect, the oil reservoir fuel temperature adjusting means uses the vaporized DME fuel as a cooling medium to cool the DME fuel in the oil reservoir. A reservoir fuel cooler, cooling medium supply means for supplying the DME fuel in the fuel tank as a cooling medium to the oil reservoir fuel cooler, and an oil for detecting the temperature of the D の fuel in the oil reservoir. Reservoir temperature detection means, wherein the DΜ fuel temperature control means detects the oil reservoir based on the temperature of the DME fuel in the oil reservoir detected by the oil reservoir fuel temperature detection means. as the temperature of the DME fuel in the chamber is the predetermined temperature T _G, the supply operation of the cooling medium by the cooling medium supply means ◦ for NZO FF control, a diesel engine, wherein a: with D ME fuel supply system is there.

According to the DME fuel supply device of the diesel engine according to the twentieth aspect of the present invention, in the DME fuel supply device of a diesel engine, the same operational effects as those of the above-described twenty-fourth aspect of the present invention can be obtained. Can be.

According to a thirtieth aspect of the present invention, in the twenty-eighth aspect, the oil reservoir fuel temperature adjusting means comprises an oil for cooling the DME fuel in the oil reservoir using the vaporized DME fuel as a cooling medium. A reservoir fuel cooler; a cooling medium supply means for supplying the DME fuel in the fuel tank as a cooling medium to the oil reservoir fuel cooler; and an oil for detecting the temperature of the DME fuel in the oil reservoir. Reservoir temperature detection means, wherein the DME fuel temperature control means comprises: The cooling medium supply is performed so that the temperature of the DME fuel in the oil reservoir becomes the specified temperature _Tc based on the temperature of the DME fuel in the oil reservoir detected by the oil reservoir fuel temperature detecting means. A DME fuel supply device for a diesel engine, wherein the supply amount of the cooling medium by means is adjusted.

According to the DME fuel supply device for a diesel engine according to the thirtieth aspect of the present invention, it is possible to obtain the same operational effects as those of the above-described twenty-fifth aspect of the present invention in the DME fuel supply device for a diesel engine. it can.

According to a thirty-first aspect of the present invention, in the thirty-fifth aspect, the cooling medium supply means is configured to control a supply amount of the cooling medium to the oil sump fuel cooler according to a rotation speed of a rotary driving force source. The oil reservoir chamber temperature control means is configured to: increase or decrease the temperature of the DME fuel in the oil reservoir detected by the oil reservoir fuel temperature detection means. is D ME fuel supply system for diesel engines - as the temperature of the DME fuel is the predetermined temperature T _Q, and has a means for controlling the rotational speed of the rotary driving power source, di which was characterized by .

According to the DME fuel supply device for a diesel engine according to the thirty-first aspect of the present invention, in the DME fuel supply device for a diesel engine, the same operational effects as those of the above-described twenty-sixth aspect of the present invention are obtained. be able to.

According to a thirty-second aspect of the present invention, in any one of the thirty-eighth to thirty-first aspects, the fuel tank temperature adjusting means is arranged so that the DME fuel delivered to the fuel tank passes through an air-cooled cooler. A first recirculation path for cooling and then returning to the fuel tank; and a second recirculation path for returning the DME fuel to the fuel tank to the fuel tank without passing through the air-cooled cooler. A return path switching means for switching between the first return path and the second return path; and a fuel tank fuel temperature for detecting a temperature of the DME fuel in the fuel tank. Detecting means for controlling the temperature of the DME fuel in the oil reservoir based on the temperature of the DME fuel in the fuel tank detected by the fuel tank fuel temperature detecting means. Yo Controlling the return path switching means such that the temperature of the DME fuel in the fuel tank becomes relatively high with a relatively constant temperature difference. It is.

According to the DME fuel supply device for a diesel engine according to the thirty-second aspect of the present invention, the same operational effects as those of the above-described twenty-sixth aspect of the present invention can be obtained in the DME fuel supply device for a diesel engine. it can.

According to a thirty-third aspect of the present invention, in any one of the thirty-eighth to thirty-second aspects, the DME fuel delivered from the injection pump is supplied to a common rail, and from the common rail to each fuel injection nozzle. This is a DME fuel supply system for diesel engines, characterized in that it is delivered.

According to the DME fuel supply device of the diesel engine according to the 33rd aspect of the present invention, in the DME fuel supply device of a common rail diesel engine, any one of the aforementioned 28th to 32nd aspects of the present invention is provided. The operation and effect according to the embodiment can be obtained. The temperature control program for DME fuel according to the thirty-fourth aspect of the present invention includes the steps of: providing DME fuel supplied from a fuel tank via a feed pipe by a predetermined amount at a predetermined timing; An injection pump for delivering to an injection pipe communicating with the injection nozzle; an oil reservoir fuel temperature adjusting means for adjusting the temperature of the DME fuel filled in an oil reservoir of the injection pump; DME fuel temperature control for causing a computer to execute DME fuel temperature control in a DME fuel supply device for a diesel engine, comprising: a fuel tank temperature control means for controlling the temperature of the DME fuel in the fuel tank. a program, as the temperature of the DME fuel in the oil reservoir chamber is defined temperature T _sigma, the oil reservoir chamber fuel temperature system for controlling the oil reservoir chamber fuel temperature regulating means Controlling the temperature control means in the fuel tank such that the temperature of the DME fuel in the fuel tank becomes relatively higher than the temperature of the DΜ fuel in the oil reservoir with a relatively substantially constant temperature difference. And a fuel tank internal temperature control procedure. According to the DME fuel temperature control program according to the thirty-fourth aspect of the present invention, the same operation and effect as those of the above-described twenty-third aspect of the present invention can be obtained. The same operational effects as those of the above-described twenty-third aspect of the present invention can be provided to any diesel engine DME fuel supply device capable of executing the program.

According to a thirty-fifth aspect of the present invention, in the thirty-fourth aspect, the oil reservoir fuel temperature adjusting means comprises an oil for cooling the DME fuel in the oil reservoir using the vaporized DME fuel as a cooling medium. A reservoir fuel cooler; a cooling medium supply means for supplying the DME fuel in the fuel tank as a cooling medium to the oil reservoir fuel cooler; and an oil reservoir for detecting a temperature of the DME fuel in the oil reservoir. A fuel tank temperature detecting means, wherein the oil sump fuel temperature control step comprises: detecting a temperature of the DME fuel in the oil sump detected by the oil sump fuel temperature detecting means. A DME fuel temperature control program, wherein the cooling medium supply means controls the supply of the cooling medium by the NMEFF so that the temperature of the DME fuel becomes the specified temperature. is there.

According to the DME fuel temperature control program of the thirty-fifth aspect of the present invention, the same operation and effect as those of the above-described second aspect of the present invention can be obtained, and the DME fuel temperature control program is executed. The DME fuel supply device of any diesel engine that can perform the same operation and effect as the above-described twenty-fourth aspect of the present invention can be provided.

According to a thirty-sixth aspect of the present invention, in the thirty-fourth aspect, the oil reservoir fuel temperature adjusting means cools the DME fuel in the oil reservoir using the deprived DME fuel as a cooling medium. An oil sump fuel cooler, cooling medium supply means for supplying the DME fuel in the fuel tank as a cooling medium to the oil sump fuel cooler, and detecting a temperature of the DME fuel in the oil sump. Oil reservoir fuel temperature detecting means for detecting oil temperature of the DME fuel in the oil reservoir detected by the oil reservoir fuel temperature detecting means. The temperature of the DME fuel in the reservoir becomes the specified temperature, A temperature control program for DME fuel, characterized by comprising a procedure for adjusting a supply amount of the cooling medium by a cooling medium supply unit.

According to the DME fuel temperature control program according to the thirty-sixth aspect of the present invention, it is possible to obtain the same operation and effect as those of the above-described twenty-fifth aspect of the present invention, The same operational effects as those of the above-described twenty-fifth aspect of the present invention can be provided to any diesel engine DME fuel supply device capable of executing the above.

In a thirty-seventh aspect of the present invention, in the thirty-sixth aspect, the cooling medium supply means is configured to control a supply amount of the cooling medium to the oil reservoir fuel cooler in accordance with a rotation speed of a rotary driving force source. The oil reservoir fuel temperature control procedure includes the step of: controlling the oil reservoir fuel temperature based on the temperature of the DME fuel in the oil reservoir detected by the oil reservoir fuel temperature detecting means. as the temperature of the DME fuel is the predetermined temperature T _e, has a procedure for controlling the rotational speed of the rotary driving power source, a temperature control program of D ME fuel characterized by.

According to the DME fuel temperature control program according to the 37th aspect of the present invention, the same operation and effect as those of the 26th aspect of the present invention can be obtained. The same operational effects as those of the above-described twenty-sixth aspect of the present invention can be provided to any DME fuel supply device capable of executing the above.

According to a thirty-eighth aspect of the present invention, in any one of the thirty-fourth to thirty-seventh aspects, the fuel tank internal temperature control means includes an air-cooled cooler for supplying the DME fuel to the fuel tank. A first return path, which is cooled through the fuel tank and then returns to the fuel tank, and a second return path in which the DME fuel delivered to the fuel tank is returned to the fuel tank without passing through the air-cooled cooler. Return route switching means for switching between the first return and the second return route; and a fuel for detecting the temperature of the DME fuel in the fuel reservoir. And a fuel temperature detecting means. The fuel tank internal temperature control procedure is based on the temperature of the DME fuel in the fuel tank detected by the fuel tank fuel temperature detecting means, and the fuel tank is controlled based on the temperature of the DME fuel in the oil reservoir. Controlling the return path switching means so that the temperature of the DME fuel in the inside becomes high with a relatively constant temperature difference. It is a program.

According to the DME fuel temperature control program according to the thirty-eighth aspect of the present invention, the same operation and effect as those of the above-described twenty-seventh aspect of the present invention can be obtained, and this DME fuel temperature control program can be used. Any DME fuel supply device that can be implemented can have the same operation and effect as the above-described twenty-seventh aspect of the present invention. BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a schematic configuration diagram showing a first embodiment of a DME fuel supply device according to the present invention.

FIG. 2 is a schematic configuration diagram showing a first embodiment of the DME fuel supply device according to the present invention, and shows a state when diesel engines are stopped.

FIG. 3 is a schematic configuration diagram showing a first embodiment of the DME fuel supply device according to the present invention, and shows a state where the DME fuel is charged.

FIG. 4 is a schematic configuration diagram showing a first embodiment of the DME fuel supply device according to the present invention, and shows a state during diesel engine operation.

FIG. 5 is a schematic configuration diagram showing a first embodiment of the DME fuel supply device according to the present invention, and shows a residual fuel recovery operation after stopping diesel fuel. FIG. 6 is a schematic configuration diagram showing a second embodiment of the DME fuel supply device according to the present invention.

FIG. 7 is a schematic configuration diagram showing a second embodiment of the DME fuel supply device according to the present invention, in which a feed pipe is connected to a feed pipe before the residual fuel recovery operation after stopping the diesel engine. It shows a state in which the phase parts are communicated.

FIG. 8 is a schematic configuration diagram showing a third embodiment of the DME fuel supply device according to the present invention.

FIG. 9 is a schematic configuration diagram showing a third embodiment of the DME fuel supply device according to the present invention, and shows a state when diesel engines are stopped.

FIG. 10 is a schematic configuration diagram showing a third embodiment of the DME fuel supply device according to the present invention, and shows a state where DME fuel is charged.

FIG. 11 is a schematic configuration diagram showing a third embodiment of the DME fuel supply device according to the present invention, and shows a state during a diesel engine operation.

FIG. 12 is a schematic configuration diagram showing a third embodiment of the DME fuel supply device according to the present invention, in which the gas phase is communicated to the feed pipe before the residual fuel recovery operation after stopping the diesel engine. It shows the state.

FIG. 13 is a schematic configuration diagram showing a third embodiment of the DME fuel supply device according to the present invention, and shows a residual fuel recovery operation after stopping diesel engines. FIG. 14 is a schematic configuration diagram showing a fourth embodiment of the DME fuel supply device according to the present invention.

FIG. 15 is a schematic configuration diagram showing a fifth embodiment of the DME fuel supply device according to the present invention.

FIG. 16 is a schematic configuration diagram showing a fifth embodiment of the DME fuel supply device according to the present invention, and shows a state when the diesel engine is stopped.

FIG. 17 is a schematic configuration diagram showing a fifth embodiment of the DME fuel supply device according to the present invention, and shows a state where DME fuel is charged.

FIG. 18 is a schematic configuration diagram showing a fifth embodiment of the DME fuel supply device according to the present invention, and shows a state during diesel engine operation.

FIG. 19 is a schematic configuration diagram showing a fifth embodiment of the DME fuel supply device according to the present invention, and shows a residual fuel recovery operation after stopping diesel engines. FIG. 20 is a schematic configuration diagram showing a sixth embodiment of the DME fuel supply device according to the present invention.

FIG. 21 is a schematic configuration diagram showing a sixth embodiment of the DME fuel supply device according to the present invention, in which the gas phase is communicated to the feed pipe before the residual fuel recovery operation after the diesel engine is stopped. FIG.

FIG. 22 is a schematic configuration diagram showing a seventh embodiment of the DME fuel supply device according to the present invention.

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FIG. 23 is a schematic configuration diagram showing a seventh embodiment of the DME fuel supply device according to the present invention, and shows a state when the diesel engine is stopped.

FIG. 24 is a schematic configuration diagram showing a seventh embodiment of the DME fuel supply device according to the present invention, and shows a state where the DME fuel is charged.

FIG. 25 is a schematic configuration diagram showing a seventh embodiment of the DME fuel supply device according to the present invention, and shows a state during a diesel engine operation.

FIG. 26 is a schematic configuration diagram showing a seventh embodiment of the DME fuel supply device according to the present invention, in which the gas phase is communicated to the feed pipe before the residual fuel recovery operation after stopping the diesel engine. FIG.

FIG. 27 is a schematic configuration diagram showing a seventh embodiment of the DME fuel supply device according to the present invention, and shows a residual fuel recovery operation after stopping diesel engines. FIG. 28 is a schematic configuration diagram showing an eighth embodiment of the DME fuel supply device according to the present invention.

FIG. 29 is a schematic configuration diagram showing a ninth embodiment of the DME fuel supply device according to the present invention.

FIG. 30 is a schematic configuration diagram showing a ninth embodiment of the DME fuel supply device according to the present invention, and shows a state when the diesel engine is stopped.

FIG. 31 is a schematic configuration diagram showing a ninth embodiment of the DME fuel supply device according to the present invention, and shows a state where the DME fuel is charged. FIG. 32 is a schematic configuration diagram showing a ninth embodiment of the DME fuel supply device according to the present invention, and shows a state during diesel engine operation.

FIG. 33 is a schematic configuration diagram showing a ninth embodiment of the DME fuel supply device according to the present invention, and shows a residual fuel recovery operation after stopping diesel engines. FIG. 34 is a flowchart showing the “procedure for controlling the temperature in the fuel tank” according to the present invention.

FIG. 35 is a flowchart showing an “oil reservoir fuel temperature control procedure” according to the present invention.

FIG. 36 is a graph schematically showing a temperature waveform of the DME fuel in the fuel tank and a temperature waveform of the DME fuel in the oil reservoir according to the present invention.

FIG. 37 is a schematic configuration diagram showing another embodiment of the DME fuel supply device according to the present invention.

FIG. 38 is a flowchart showing an “oil reservoir fuel temperature control procedure” in the DME fuel supply device for the diesel engine shown in FIG. 37.

FIG. 39 is a graph schematically showing the temperature waveform of the DME fuel in the fuel tank according to the present invention and the temperature waveform of the DME fuel in the oil reservoir, in which the rotation speed of the electric compressor is controlled. This shows the temperature control of the DME fuel in the oil reservoir by the c.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

First, a first embodiment of a DME fuel supply device for a diesel engine according to the present invention will be described. FIG. 1 is a schematic configuration diagram illustrating a DME fuel supply device according to a first embodiment of the present invention.

The DME fuel supply device 100 according to the present invention for supplying DME fuel to a diesel engine includes an injection pump 1. The DME fuel in the liquid part 4 a of the fuel tank 4 is filtered from the liquid fuel outlet 41 through a filter 5 a and then fed. The oil is supplied to the oil reservoir 11 of the injection pump 1 via the pipe 5 and the three-way solenoid valve 21. The three-way solenoid valve 21, which is a component of the “remaining fuel recovery means” described later, is in the ON state during the injection state (during operation of the diesel engine), and the feed pipe 5 communicates with the oil reservoir 11. I have. The injection pump 1 is provided with the same number of injection pump elements 2 as the number of cylinders of the diesel engine. An injection pipe 3 is connected to a fuel outlet of the injection pump element 2, and the injection pipe 3 is connected to a fuel injection nozzle 9, and the DME fuel compressed to a high pressure sent from the injection pump 1 is used for injection. The fuel is fed to the fuel injection nozzle 9 via the injection pipe 3. The DME fuel overflowing from the fuel injection nozzle 9 is returned to the feed pipe 5 via the nozzle return pipe 7 and is supplied again to the oil reservoir 11.

Outside the oil reservoir 11, an “oil reservoir fuel cooling device 60” for cooling the DME fuel in the oil reservoir 11 is provided. DME fuel is supplied as a refrigerant from the fuel tank 4 to the “oil reservoir fuel cooling device 60” via a refrigerant supply pipe 51 branched from the feed pipe 5. The DME fuel supplied as the refrigerant is supplied to the fuel gas dehydrator 15 through the refrigerant supply pipe opening / closing solenoid valve 16. Then, the DME fuel gasified by the fuel vaporizer 15 is supplied to the fuel cooler 6 utilizing the heat of vaporization, and the DME fuel in the oil reservoir 11 is cooled by the heat of vaporization. You. The “oil reservoir fuel cooling device 60” is controlled by opening and closing the refrigerant supply pipe opening and closing solenoid valve 16.

The cam chamber 12 is a dedicated lubrication system separated from the diesel engine lubrication system, and the oil separator 13 leaks from the injection pump element 2 to the cam chamber 12: DME fuel The mixed lubricating oil in the cam chamber 12 is separated into DME fuel and lubricating oil, and the lubricating oil is returned to the cam chamber 12. The DME fuel separated in the oil separator 13 is sent out to the electric compressor 23 via a check valve 14 for preventing the pressure in the cam chamber 12 from becoming lower than the atmospheric pressure. After being pressurized in 2, it is returned to the fuel tank 4. In addition, the “oil reservoir fuel cooling system” The DME fuel supplied as a refrigerant to the fuel cooler 6 is also pressurized by the electric compressor 23 and then returned to the fuel tank 4.

Thus, using the electric compressor 23 for recovering the DME fuel separated at the oil separator 13, the DME fuel was supplied from the refrigerant supply pipe 51 to the “oil reservoir fuel cooling device”: D By sending the ME fuel to the fuel tank 4, the DME fuel supplied as the refrigerant to the “oil reservoir fuel cooling device” can be recovered without providing a dedicated refrigerant recovery unit.

When the three-way solenoid valve 22 is OFF, the DME fuel pressurized by the electric compressor 23 is cooled by the cooler 42 as “air-cooled cooling ^” before the fuel tank Returned to 4 (first return path). When the three-way solenoid valve 22 is ON, the fuel is returned to the fuel tank 4 without passing through the cooler 42, that is, without being cooled (the second restart path). Therefore, the temperature of the DME fuel returned to the fuel tank 4 can be adjusted by ON / OFF control of the three-way solenoid valve 2 2, thereby controlling the temperature of the DME fuel in the fuel tank 4. can do. The check valve 43 prevents the DME fuel from flowing back to the cooler 42 from the second return path.

Next, regarding the operation of the DME fuel supply device 100 shown in the embodiment, the DME fuel supply stop operation, the DME fuel charging operation, the diesel engine operation state, and the residual fuel recovery operation after the diesel engine is stopped are sequentially performed. Will be described later.

FIG. 2 is a schematic configuration diagram showing a first embodiment of the DME fuel supply device 100 according to the present invention, and shows a state when diesel engines are stopped.

When the diesel engine is stopped, the three-way solenoid valve 21 and the three-way solenoid valve 22 and the coolant supply pipe opening / closing solenoid valve 16 are all OFF. The three-way solenoid valve 21 and the three-way solenoid valve 22 communicate with each other in the communication direction shown in the OFF state. The refrigerant supply pipe opening / closing electromagnetic valve 16 is an electromagnetic valve that communicates in an OFF state. FIG. 3 is a schematic configuration diagram showing a first embodiment of the DME fuel supply device 100 according to the present invention, and shows a state in which DME fuel is charged.

To operate the diesel engine from the stopped state, the DME fuel in the fuel tank 4 is supplied to the oil reservoir 11 of the injection pump 1, the injection pipe 3, the nozzle pipe 7 of the nozzle, and the refrigerant supply pipe 51. Fill. First, the three-way solenoid valve 21 and the three-way solenoid valve 22 are in the ON state, and a communication path in the illustrated direction is formed for each. Subsequently, the electric compressor 23 is turned on, the return pipe 8 is sucked in the direction indicated by the symbol A, and the second return path communicated by the three-way solenoid valve 22 in the on state is indicated by the symbol B. The gas phase 4 b in the fuel tank 4 is pressurized in the direction. When the gas phase 4b in the fuel tank 4 is pressurized, the DME fuel in the liquid phase 4a is sent out to the feed pipe 5 (symbol C), and the oil sump chamber 11, the injection pipe 3, and the nozzle The return pipe 7 and the refrigerant supply pipe 51 are filled with DME fuel in the direction indicated by the symbol D. The DME fuel supplied as a refrigerant from the refrigerant supply pipe 51 is degassed by the fuel vaporizer 15 and sent out to the fuel cooler 6 of the “oil reservoir fuel cooling device”, where the heat of vaporization is obtained. As a result, the DME fuel filled in the oil reservoir 11 is cooled.

FIG. 4 is a schematic configuration diagram showing a first embodiment of the DME fuel supply device 100 according to the present invention, and shows a state during a diesel engine operation.

When each part is filled with the DME fuel, the DME fuel in the fuel tank 4 is filled with the DME fuel in the oil reservoir 11 cooled by the “oil reservoir fuel cooling device” and the fuel tank 4. Due to the relative pressure difference between the two due to the temperature difference with the DME fuel, it is pumped to the feed pipe 5 (reference E). That is, the DME fuel supply device 100 according to the present invention does not include a pump for sending the DME fuel from the fuel tank 4 to the injection pump 1, and the DME fuel in the oil reservoir 11 is not provided. Due to the pressure difference between the oil reservoir 11 and the inside of the fuel tank 4 caused by cooling the DME fuel, the DME fuel in the fuel tank 4 is supplied to the injection pump 1. Therefore, the oil reservoir 11 does not have an overflow channel, and the DME pumped from the oil reservoir 11 to the fuel injection nozzle 9 via the injection pipe 3 by the injection pump element 2 (reference F). It will be supplied only for the amount of fuel. Also, the DME fuel did not return to the fuel tank 4 as before, but returned to the feed pipe 5 via the nozzle return pipe 7 and returned to the oil reservoir 1 again. Supplied to 1. In this way, the fuel cooler 6, which effectively utilizes the excellent characteristics of the DME fuel as a refrigerant, makes it possible to rationally configure the "oil reservoir fuel cooling device". This is unnecessary, and the cost of the diesel engine DME fuel supply device 100 can be reduced.

In the oil reservoir 11, a temperature sensor 1 la (oil reservoir fuel temperature detecting means) is provided. The cooling temperature of the oil reservoir 11 is controlled to be a constant cooling temperature by controlling the opening and closing of the refrigerant supply pipe opening and closing solenoid valve 16. That is, when the temperature of the DME fuel in the oil reservoir 11 detected by the temperature sensor disposed in the oil reservoir 11 falls below a predetermined temperature, the refrigerant supply pipe opening / closing solenoid valve 16 is controlled to close. (ON), and when the temperature exceeds a predetermined temperature, the refrigerant supply pipe opening / closing solenoid valve 16 is opened (OFF) to maintain the temperature of the DME fuel in the oil reservoir 11 constant. Thereby, the injection characteristics of the DME fuel of the injection pump 1 can be stabilized. In the fuel tank 4, a temperature sensor 4c (means for detecting the temperature in the fuel tank) is provided. The temperature of the DME fuel in the oil reservoir 11 and the temperature of the DME fuel in the fuel tank 4 are determined. The three-way solenoid valve 2 2 (return path switching solenoid valve) is controlled so that the temperature difference between the three-way solenoid valve 22 and the fuel tank 4 becomes constant, that is, the temperature difference between the oil reservoir 11 and the fuel tank 4 becomes constant. The temperature control means 22 a in the fuel tank is configured so as to control the temperature of the DME fuel in the fuel tank 4 by ONZOFF control of the valve. This makes it possible to keep the delivery pressure of the DME fuel delivered from the fuel tank 4 to the feed pipe 5 constant (fuel tank temperature control means). Therefore, the fuel tank The temperature of the DME fuel in the oil reservoir 11 can be controlled to the optimum temperature while maintaining the relative temperature difference from the inside of the fuel 4, so that the optimal DME fuel injection Properties can be obtained.

FIG. 5 is a schematic configuration diagram showing a first embodiment of the DME fuel supply device 100 according to the present invention, and shows a residual fuel recovery operation after the diesel engine is stopped. After stopping the diesel engine, the cylinder is filled with vaporized DME fuel to prevent abnormal combustion such as noking that occurs when the diesel engine is restarted.The oil reservoir 11, the injection pipe 3, and the nozzle The DME fuel filled in the pump 7 and the refrigerant supply pipe 51 is recovered to the fuel tank 4 by the residual fuel recovery means 2 la. The residual fuel recovery means 21a is composed of a three-way solenoid valve 21 (communication path switching means) and an electric compressor 23. When the three-way solenoid valve 21 is turned off after the diesel engine is stopped, the electric compressor 23 fills the oil reservoir 11, the injection pipe 3, the nozzle pipe 7, and the refrigerant supply pipe 51. The collected DME fuel is collected in the fuel tank 4 through the route indicated by reference symbol J. When the three-way solenoid valve 22 is turned off, the recovered DME fuel is cooled by the cooler 14 2 in the first return route (the route indicated by the symbol H) and then recovered to the fuel tank 4. You.

In this way, the DME fuel can be supplied from the fuel tank to the oil reservoir without using a driving means such as a feed pump.

Further, as a second embodiment, in addition to the above-described first embodiment, a configuration in which the gas phase portion 4b of the fuel tank 4 and the feed pipe 5 can be connected to each other is exemplified. FIG. 6 is a schematic configuration diagram showing a second embodiment of the DME fuel supply device 100 according to the present invention. The gas phase portion 4b of the fuel tank 4 is connected to the feed pipe 5 from the gas phase fuel outlet 44 through the gas phase fuel output pipe 311 and the 3-way solenoid valve 31. When the three-way solenoid valve 31 is in the FF state, the DME fuel supply device 100 communicates with the oil reservoir 11 and the liquid phase portion 4 a of the fuel tank 4, and the three-way solenoid valve 3 If 1 is in the 0 N state, The oil reservoir 11 communicates with the gas phase portion 4b of the fuel tank 4. In this embodiment, after the diesel engine stops, the remaining fuel is filled into the oil sump chamber 11, the injection pipe 3, the nozzle return pipe 7, and the refrigerant supply pipe 51 by the "remaining fuel recovery means". Before the collected DME fuel is collected in the fuel tank 4, the three-way solenoid valve 31 is turned on and the high-pressure gaseous DME fuel in the gas phase section 4b is sent to the feed pipe 5 (gas phase Fuel delivery means).

FIG. 7 is a schematic configuration diagram showing a second embodiment of the DME fuel supply device 100 according to the present invention, in which a gas phase is supplied to the feed pipe 5 before the residual fuel recovery operation after stopping the diesel engine. This shows a state in which the parts 4b are connected to each other.

Since the gas phase 4 b of the fuel tank 4 is filled with high-pressure gaseous DME fuel, the three-way electric valve 31 is turned on when the diesel engine is stopped, and the liquid phase of the fuel tank 4 is turned on. When the communication between 4a and the feed pipe 5 is cut off and the gas phase 4 of the fuel tank 4 is connected to the feed pipe 5, the gaseous DME fuel in the gas phase 4b passes through the path indicated by the symbol K. Sent out. The DME fuel in the feed pipe 5 on the side of the oil reservoir 11 from the three-way solenoid valve 31 and the DME fuel charged in the refrigerant supply pipe 51 are supplied through the fuel cooler 6 to the symbol L. The fuel is collected in the fuel tank 4 by the electric compressor 23 along the route indicated by.

As described above, before the DME fuel remaining in the oil reservoir 11 and the nozzle return pipe 7 is recovered by the “remaining fuel recovery means”, the feed pipe is previously prepared by the “gas phase fuel delivery means”. 5, and a part of the DME fuel remaining in the refrigerant supply pipe 51 can be recovered to the fuel tank 4 by the electric compressor 23, so the D vaporized in the feed pipe 5 and the refrigerant supply pipe 51 The ME fuel is filled, and the time required for DME fuel recovery by the “residual fuel recovery means” can be reduced.

Further, as a third embodiment, in addition to the above-described second embodiment, a sub-fuel tank having a smaller capacity than the fuel tank 4 is provided between the fuel tank 4 and the feed pipe 5. Is included. FIG. 8 is a schematic configuration diagram showing a third embodiment of the DME fuel supply device 100 according to the present invention.

Between the fuel tank 4 and the feed pipe 5, a sub-fuel tank 45 having a smaller capacity than the fuel tank 4 is provided. In this embodiment, the capacity of the sub fuel tank 45 is about 1/1000 of the fuel tank 4. The DME fuel supply device 100 shown in this embodiment fills the oil reservoir 11, the injection pipe 3, the nozzle return pipe 7, and the refrigerant supply pipe 51 with DME fuel when the diesel engine is started. In this case, DME fuel is supplied not from the fuel tank 4 but from the sub fuel tank 45.

Subsequently, the operation of the DME fuel supply device 100 shown in this embodiment is changed from the diesel engine stopped state to the DME fuel filling operation, the diesel engine operation state, and the residual fuel recovery operation after the diesel engine is stopped. It will be described step by step. Note that parts similar to those in the first and second embodiments will be partially omitted from the description. FIG. 9 is a schematic configuration diagram showing a third embodiment of the DME fuel supply device 100 according to the present invention, and shows a state when diesel engines are stopped.

When the diesel engine is stopped, the three-way solenoid valve 21 and the three-way solenoid valve 22 and the refrigerant supply pipe opening / closing solenoid valve 16 are all OFF. Further, the three-way solenoid valve 33 and the solenoid valve 32 for opening and closing the communication between the fuel tank 4 and the sub fuel tank 45 are also OFF. As shown, the three-way solenoid valve 33 communicates with the fuel tank 4 in the OFF state, and the solenoid valve 32 communicates with the fuel tank 4 and the sub fuel tank 45 in the OFF state.

FIG. 10 is a schematic configuration diagram showing a third embodiment of the DME fuel supply device 100 according to the present invention, and shows a state where DME fuel is being charged.

In order to operate the diesel engine from a standstill, the DME fuel in the fuel tank 4 is filled with the oil reservoir 11 of the injection pump 1, the injection pipe 3, the nozzle pipe 7 and the coolant supply pipe 5 1 Fill into. First, a three-way solenoid valve 21 and the three-way solenoid valve 22 are turned ON, and each constitutes a communication path in the direction shown. Also, the three-way solenoid valve 33 and the solenoid valve 32 are in the 〇N state, the communication between the fuel tank 4 and the sub fuel tank 45 is cut off, and the communication path from the three-way solenoid valve 22 is changed to the sub fuel tank. Connect to 4-5. Subsequently, the electric compressor 23 is turned on, the return pipe 8 is sucked in the direction indicated by the symbol A, and the three-way solenoid valve 22 in the ON state and the sub fuel tank 4 communicated with the three-way solenoid valve 33 are turned on. 5 is pressurized in the direction indicated by the symbol M, and the gas phase in the sub fuel tank 45 is pressurized. When the gas phase in the fuel tank 45 is pressurized, the DME fuel in the sub fuel tank 45 is delivered to the feed pipe 5 (reference numeral N), and the oil reservoir 11 and the injection pipe 3 The DME fuel is charged into the nozzle return pipe 7 and the refrigerant supply pipe 51 in the direction indicated by the symbol N.

FIG. 11 is a schematic configuration diagram showing a third embodiment of the DME fuel supply device 100 according to the present invention, and shows a state during diesel engine operation.

When each part is filled with the DME fuel, the three-way solenoid valve 22, the three-way solenoid valve 33, and the solenoid valve 32 change from the ON state to the OFF state. Therefore, the return pipe 8 communicates with the cooler 14 through the electric compressor 23, and the DME fuel in the fuel tank 4 is cooled in the oil reservoir 11 cooled by the “oil reservoir fuel cooling device”. Due to the relative pressure difference between the DME fuel and the DME fuel in the fuel tank 4 caused by the temperature difference between the DME fuel and the DME fuel, the fuel is pumped to the feed pipe 5 via the sub fuel tank 45 (reference numeral N). ;). In the oil reservoir 11, the fuel tank is filled by the amount of the DME fuel that has been pumped (reference F) from the oil reservoir 11 to the fuel injection nozzle 9 via the injection pipe 3 by the injection pump element 2. It will be supplied from 4 via the sub fuel tank 45. The DME fuel that has overflowed from the fuel injection nozzle 9 is returned to the feed pipe 5 via the nozzle return pipe 7 without being returned to the fuel tank 4 as in the conventional case, and is returned to the oil reservoir 11 again. Supplied to

FIG. 12 is a schematic view showing a third embodiment of the DME fuel supply device 100 according to the present invention. FIG. 3 is a configuration diagram showing a state in which a gas phase section 4b is connected to a feed pipe 5 before a residual fuel recovery operation after the diesel engine is stopped.

As in the second embodiment, when the diesel engine is stopped, the three-way valve 31 is set to the 〇N state, the communication between the liquid phase portion 4a of the fuel tank 4 and the feed pipe 5 is cut off, and the fuel When the gas phase portion 4b of the tank 4 is communicated with the feed pipe 5, the gaseous DME fuel in the gas phase portion 4b is sent out through the path indicated by the symbol K. The DME fuel in the feed pipe 5 on the side of the oil reservoir 11 from the three-way solenoid valve 31 and the DME fuel filled in the refrigerant supply pipe 51 are denoted by L through the fuel cooler 6. The fuel is recovered to the fuel tank 4 by the electric compressor 13 through the route indicated by.

FIG. 13 is a schematic configuration diagram showing a third embodiment of the DME fuel supply device 10 ° according to the present invention, and shows a residual fuel recovery operation after stopping diesel engines.

As in the first and second embodiments, after the diesel engine is stopped, abnormal combustion such as knocking that occurs when the diesel engine is restarted due to the filled DME fuel in the cylinder after the diesel engine is stopped. DME fuel filled in the oil sump 11, injection pipe 3, nozzle return pipe 7, and refrigerant supply pipe 51 to the fuel tank 4 by `` residual fuel recovery means '' to recover. “Residual fuel recovery means” is composed of a three-way solenoid valve 21 (communication path switching means) and an electric compressor 23. When the three-way solenoid valve 21 is turned off after the diesel engine stops, the electric compressor 23 fills the oil reservoir 11, the injection pipe 3, the nozzle return pipe 7, and the refrigerant supply pipe 51 with DME. Fuel is recovered to fuel tank 4 along the path indicated by reference symbol J. The DME fuel recovered by turning off the three-way solenoid valve 22 is cooled by the cooler 14 in the first return route (the route indicated by the symbol H) and then recovered to the fuel tank 4. Is done.

In this way, D fuel can be removed from the fuel tank without using a driving means such as a feed pump. ME fuel can be supplied to the oil reservoir. Also, since the capacity of the sub fuel tank 45 is smaller than that of the fuel tank 4, the pressurization time by the electric compressor 23 can be short, and the DME fuel is transferred to the oil reservoir 11 by the pressing force of the electric compressor 23. The filling time can be reduced. In addition, the capacity of the sub fuel tank 45 is smaller than that of the oil reservoir 11, the injection pipe 3, the nozzle return pipe 7, and the refrigerant supply pipe 51 as long as the DME fuel can be charged. It can be said that the faster the DME fuel can be filled, the better.

Further, as a fourth embodiment, a DME fuel supply device 100 in the third embodiment is a common rail type. FIG. 14 is a schematic configuration diagram showing a fourth embodiment of the DME fuel supply device 100 according to the present invention. Thus, the common rail type DME fuel supply device 100 in which the DME fuel pressure-fed from the injection pump 1 is supplied via the common rail 91 to which each fuel injection nozzle 9 is connected. The present invention can also be implemented, and the operation and effect of the present invention can be obtained.

Next, fifth to eighth embodiments of the present invention will be described. FIG. 15 is a schematic configuration diagram showing a fifth embodiment of the DME fuel supply device according to the present invention, and FIG. 16 is a fifth embodiment of the DME fuel supply device 100 according to the present invention. FIG. 2 is a schematic configuration diagram illustrating a state when the diesel engine is stopped. FIG. 17 is a schematic configuration diagram showing a fifth embodiment of the DME fuel supply device 100 according to the present invention, and shows a state where DME fuel is being charged. FIG. 18 is a schematic configuration diagram illustrating a fifth embodiment of the DME fuel supply device 100 according to the present invention, and illustrates a state during operation of the diesel engine. FIG. 19 is a schematic configuration diagram showing a fifth embodiment of the DME fuel supply device 100 according to the present invention, and shows a residual fuel recovery operation after the diesel engine is stopped.

As is apparent from a comparison of FIG. 15 with FIG. 1, the fifth embodiment includes many parts having the same configuration as the first embodiment. During ~ Explain to my heart.

Hereinafter, in describing the fifth to eighth embodiments with reference to the drawings, the same reference numerals as those used in the first to fourth embodiments will be used to refer to the fifth to eighth embodiments. When given to the members or portions shown in the drawings corresponding to the embodiments, unless otherwise specified, the same members or portions as those described in the first to fourth embodiments are used. There is.

The fifth embodiment of the present invention does not include the fuel cooler 6 as described in the first to fourth embodiments. In this example, as shown in FIG. 15, a cam chamber 1 is provided outside the cam chamber 12 as an “oil sump fuel cooling device 6 1” for cooling the DME fuel in the oil sump 11. A fuel gas mist device 15 for discharging the vaporized DME fuel as a refrigerant is provided in the fuel cell 2. DME fuel is supplied as a refrigerant to the fuel vaporizer 15 from the fuel tank 4 via a refrigerant supply pipe 51 branched from the feed pipe 5. The DME fuel supplied as the refrigerant is supplied to the fuel vaporizer 15 via the refrigerant supply pipe opening / closing solenoid valve 16. Then, the DME fuel degassed by the fuel carburetor 15 is discharged into the cam chamber 12, and the DME fuel in the oil storage chamber 11 is dissipated into the cam chamber 1 2 The cooling is effected via an injection pump element 2 arranged over the chamber 11. The oil reservoir fuel cooling device 61 is controlled by opening and closing a refrigerant supply pipe opening and closing electromagnetic valve 16.

The cam chamber 12 is a dedicated lubrication system that is separated from the diesel engine lubrication system.The oil separator 13 is a cam with DME fuel mixed into the cam chamber 12 from the injection pump element 2. The lubricating oil in the chamber 12 is separated into DME fuel and lubricating oil, and the lubricating oil is returned to the cam chamber 12. The DME fuel separated in the oil separator 13 is sent to the electric compressor 23 through the check valve 14 that prevents the pressure in the cam chamber 12 from becoming lower than the atmospheric pressure. After being pressurized by the compressor 23, it is returned to the fuel tank 4. Therefore, the DME fuel discharged into the cam chamber 12 as a refrigerant by the fuel carburetor 15 is also used in the oil separator 13 After being separated from the lubricating oil by the compressor and pressurized by the electric compressor 23, it is returned to the fuel tank 4.

Thus, the oil separator 13 and the electric compressor 23 for separating the DME fuel leaked from the injection pump element 2 into the cam chamber 12 and mixed with the lubricating oil and collecting the DME fuel in the fuel tank 4 A dedicated refrigerant recovery means is provided by collecting the DME fuel supplied from the refrigerant supply pipe 51 to the fuel gas deflector 15 and discharged into the cam chamber 12 into the fuel tank 4 using the Thus, the DME fuel supplied to the oil reservoir fuel cooling device 61 as a refrigerant can be recovered.

Referring to Fig. 17, in order to operate the diesel engine from a standstill, the DME fuel in the fuel tank 4 is supplied to the oil reservoir 11 of the injection pump 1, the injection pipe 3, the nozzle return pipe 7, and the refrigerant supply pipe. 5 Fill into 1. First, the three-way solenoid valve 21 and the three-way solenoid valve 22 are in the ON state, and communication paths are formed in the directions shown in the drawings. Subsequently, the electric compressor 23 is turned on, the return pipe 8 is sucked in the direction indicated by the symbol A, and the second return path communicated by the three-way solenoid valve 22 in the ON state is indicated by the symbol B. The gas phase portion 4b in the fuel tank 4 is pressurized in the direction shown by. When the gas phase 4 b in the fuel tank 4 is pressurized, the DME fuel in the liquid phase 4 a is delivered to the feed pipe 5 (reference C), and the oil reservoir 11, the injection pipe 3, The DME fuel is charged into the nozzle return pipe 7 and the refrigerant supply pipe 51 in the direction indicated by the symbol D. Then, in this example, the DME fuel supplied as the refrigerant from the refrigerant supply pipe 51 is vaporized by the fuel vaporizer 15 and discharged into the cam chamber 12, and the heat of vaporization causes the DME fuel to flow into the oil reservoir 11. The DME fuel filled in is cooled.

As shown in FIG. 18, the DME fuel overflowed from the fuel injection nozzle 9 is returned to the feed pipe 5 via the nozzle return pipe 7 without being returned to the fuel nozzle 4 as in the conventional case. However, it is supplied to the oil sump 11 again. In this way, the vaporized DME fuel is discharged into the cam chamber 12 and the excellent characteristics of the DME fuel as a refrigerant are effective. By using this, the "oil reservoir fuel cooling means" can be rationally configured, so that a drive means such as a feed pump is not required, and the cost of the DME fuel supply device 100 for diesel engines is reduced. Can be done.

Regarding this embodiment, FIG. 16 showing the state when the diesel engine is stopped and FIG. 19 showing the residual fuel recovery operation after the diesel engine is stopped are not particularly described, but the parts not described are not described. This is the same as the first embodiment. Parts not described with reference to FIGS. 15, 17, and 18 are also the same as those in the first embodiment.

FIG. 20 is a schematic configuration diagram showing a sixth embodiment of the DME fuel supply device 100 according to the present invention. FIG. 21 is a schematic configuration diagram showing a sixth embodiment of the DME fuel supply device 100 according to the present invention, in which the gas phase section 4 is fed to the feed pipe 5 before the residual fuel recovery operation after stopping the diesel engine. This shows a state where b is communicated.

In the sixth embodiment, in addition to the fifth embodiment, the gas phase portion 4b of the fuel tank 4 and the feed pipe 5 can be connected. The sixth embodiment is basically the same as the first embodiment, except that the gas phase portion 4b of the fuel tank 4 and the feed pipe 5 can be connected to each other. Since the same operation and effect as in the second embodiment can be obtained by the change, the description is omitted here. FIG. 22 is a schematic configuration diagram showing a seventh embodiment of the DME fuel supply device 100 according to the present invention. FIG. 23 is a schematic configuration diagram showing a seventh embodiment of the DME fuel supply device 100 according to the present invention, and shows a state when the diesel engine is stopped. FIG. 24 is a schematic configuration diagram showing a seventh embodiment of the DME fuel supply device 10 ° according to the present invention, and shows a state where DME fuel is charged. FIG. 25 is a schematic configuration diagram showing a seventh embodiment of the DME fuel supply device 100 according to the present invention, and shows a state during operation of the diesel engine. FIG. 26 is a schematic configuration diagram showing a seventh embodiment of the DME fuel supply device 100 according to the present invention, in which the gaseous phase section is supplied to the feed pipe 5 before the residual fuel recovery operation after stopping the diesel engine. This shows the state where 4b is connected. FIG. 27 shows a DME fuel supply device 1 according to the present invention. FIG. 14 is a schematic configuration diagram illustrating a seventh embodiment of the present invention, and illustrates a residual fuel recovery operation after the diesel engine is stopped.

In the seventh embodiment, in addition to the sixth embodiment, a sub fuel tank having a smaller capacity than the fuel tank 4 is provided between the fuel tank 4 and the feed pipe 5. The seventh embodiment is basically the same as the second embodiment, except that a sub-fuel tank having a smaller capacity than the fuel tank 4 is provided between the fuel tank 4 and the feed pipe 5 in addition to the second embodiment. This is a change, and the same operation and effect as in the second embodiment can be obtained by the change, so that the description is omitted here.

FIG. 28 is a schematic configuration diagram showing an eighth embodiment of the DME fuel supply device 100 according to the present invention. The eighth embodiment differs from the seventh embodiment in that the DME fuel supply device 100 is a common rail type. Similarly to the fourth embodiment, the common rail type DME fuel supply device 100 in which the DME fuel pressure-fed from the injection pump 1 is supplied through a common rail 91 to which each fuel injection nozzle 9 is connected. The present invention can be implemented, and the operation and effect of the present invention can be obtained.

According to the above invention, there is provided a diesel engine DME fuel supply device capable of supplying DME fuel from a fuel tank to an oil reservoir of an injection pump without using a driving means such as a feed pump. be able to.

Next, a ninth embodiment of the present invention will be described. FIG. 29 is a schematic configuration diagram showing a ninth embodiment of the DME fuel supply device 100 according to the present invention. FIG. 30 is a schematic configuration diagram showing a ninth embodiment of the DME fuel supply device 100 according to the present invention, showing a state where the diesel engine is stopped. FIG. 31 is a schematic configuration diagram showing a ninth embodiment of the DME fuel supply device 100 according to the present invention, and shows a state where DME fuel is being charged. FIG. 32 is a schematic configuration diagram showing a ninth embodiment of the DME fuel supply device 100 according to the present invention, and shows a state during operation of the diesel engine. FIG. 33 shows a DME fuel supply device 100 according to the present invention. FIG. 9 is a schematic configuration diagram showing a ninth embodiment, illustrating a residual fuel recovery operation after stopping diesel fuel.

As is clear from the comparison of FIG. 29 with FIG. 1, the ninth embodiment includes many parts having the same configuration as the first embodiment. I will explain mainly.

Hereinafter, in describing the ninth embodiment with reference to the drawings, the same reference numerals as those used in the first to fourth embodiments are shown in FIGS. 29 to 33. Unless otherwise specified, it is assumed that the same members or portions are the same as those described in the first to fourth embodiments.

As shown in FIG. 29, in the ninth embodiment, the cam chamber 12 is a dedicated lubrication system separated from the lubrication system of the diesel engine, and the oil separator 13 is an injection pump element. Separate the DME fuel leaked from 2 into the cam chamber 12 from the lubricating oil. The DME fuel separated in the oil separator 13 is sent to the electric compressor 23 via a check valve 14 for preventing the pressure in the cam chamber 12 from becoming lower than the atmospheric pressure. After being pressurized by the electric compressor 23, it is returned to the fuel tank 4.

Outside the oil reservoir 11, “oil reservoir fuel temperature control means” for cooling the DME fuel in the oil reservoir 11 is provided. DME fuel is supplied to the “oil reservoir fuel temperature adjusting means” as a cooling medium from the fuel tank 4 via a cooling medium supply pipe 51 branched from the feed pipe 5. The DME fuel supplied as the cooling medium is supplied to the fuel gas radiator 15 via the cooling medium supply pipe opening / closing solenoid valve 16. Then, the DME fuel gasified by the fuel vaporizer 15 is supplied to the oil reservoir fuel cooler 106 using the heat of vaporization, and the DME fuel in the oil reservoir 11 is heated by the heat of vaporization. Fuel is cooled. The DME fuel supplied as a cooling medium to the oil reservoir fuel cooler 106 is sucked by the electric compressor 23 and returned to the fuel tank 4.

Pressurized by electric compressor 23: D ME fuel, return path switching electromagnetic When the valve 122 is OFF, it is cooled by the cooler 42 as an “air cooling cooler” and then returned to the fuel tank 4 (first return path). When the return path switching electromagnetic valve 122 is ON, the fuel is returned to the fuel tank 4 without passing through the cooler 42, that is, without being cooled (second return path). Therefore, the temperature of the DME fuel returned to the fuel tank 4 can be adjusted by the ONZOFF control of the return path switching solenoid valve 122, whereby the temperature of the DME fuel in the fuel tank 4 can be controlled ( Temperature control means in the fuel tank). The check valve 43 is for preventing the DME fuel from flowing back to the cooler 42 from the second return path.

The “oil reservoir fuel temperature adjusting means” is controlled by the DME fuel temperature control unit 10 as “DME fuel temperature control means”, and specifically, the oil reservoir as “oil reservoir fuel temperature detecting means”. The cooling medium supply pipe opening / closing solenoid valve 16 is controlled to open and close based on the temperature of the DME fuel in the oil sump 11 detected by the chamber temperature sensor 11a. ONZOFF control of cooling medium supply. The “fuel tank temperature control means” is also controlled by the DME fuel temperature control unit 10, and specifically, the fuel detected by the fuel tank temperature sensor 4c as “fuel tank fuel temperature detection means”. The return path switching solenoid valve 122 is ONZOFF controlled based on the temperature of the DME fuel in the tank 4.

Next, regarding the operation of the DME fuel supply device 100 shown in the present embodiment, the DME fuel supply operation, the DME fuel supply operation, the Diesel Engine operation state, and the residual fuel recovery operation after the diesel engine is stopped are sequentially performed. explain.

Referring to FIG. 30, when the diesel engine is stopped, the three-way solenoid valve 21, the re-start path switching solenoid valve 122, and the cooling medium supply pipe opening / closing solenoid valve 16 are all OFF. The three-way solenoid valve 21 and the return path switching solenoid valve 122 communicate with each other in the illustrated communication direction in an OFF state. The cooling medium supply pipe opening / closing electromagnetic valve 16 is an electromagnetic valve that communicates in an OFF state. Referring to Fig. 31, in order to operate the diesel engine from a standstill, the DME fuel in the fuel tank 4 is supplied with the oil reservoir 11 of the injection pump 1, the injection pipe 3, the nozzle return pipe A, and the cooling medium supply pipe. 5 Fill into 1. First, the three-way solenoid valve 21 and the return path switching solenoid valve 122 are turned ON, and a communication path in the illustrated direction is formed. Subsequently, the electric compressor 23 is turned on, the return pipe 8 is sucked in the direction indicated by the symbol A, and the second return path communicated by the on-state restart path switching solenoid valve 122 is turned on. The gas phase 4b in the fuel tank 4 is pressurized by being pressurized in the direction indicated by the symbol B. When the gas phase 4 b in the fuel tank 4 is pressurized, the DME fuel in the liquid phase 4 a is delivered to the feed pipe 5 (reference C), and the oil reservoir 11, the injection pipe 3, and the nozzle The return pipe 7 and the cooling medium supply pipe 51 are filled with the DME fuel in the direction indicated by the symbol D. DME fuel supplied as a cooling medium from the cooling medium supply pipe 51 is vaporized by a fuel vaporizer 15 and sent to an oil reservoir fuel cooler 106, and the heat of vaporization causes the oil reservoir to emit oil. 1 The DME fuel charged in 1 is cooled.

Referring to FIG. 32, when each part is filled with the DME fuel, the DME fuel in the fuel tank 4 is combined with the DME fuel in the oil reservoir 11 cooled by the oil reservoir fuel cooler 106. The fuel is fed to the feed pipe 5 by a relative pressure difference between the fuel tank 4 and the DME fuel due to a temperature difference between the fuel and the DME fuel (reference E). That is, the DME fuel supply device 100 according to the present invention does not include a pump for sending the DME fuel from the fuel tank 4 to the injection pump 1, and the DME fuel in the oil reservoir 11 is not provided. The configuration is such that the DME fuel in the fuel tank 4 is supplied to the injection pump 1 by the pressure difference between the oil reservoir 11 and the fuel tank 4 caused by cooling the fuel tank.

Therefore, no overflow path is provided in the oil sump chamber 1 1, and the injection pipe is moved from the oil sump chamber 1 1 by the injection pump element 2. The amount of the DME fuel that has been pressure-fed (reference F) to the fuel injection nozzle 9 via 3 will be supplied. Also, the DME fuel overflowing from the fuel injection nozzle 9 is returned to the feed pipe 5 via the nozzle return pipe 7 without being returned to the fuel tank 4 as in the conventional case, and is supplied to the oil reservoir 11 again. . In this way, the oil reservoir fuel cooler 106, which effectively utilizes the excellent characteristics of the DME fuel as a cooling medium, rationally constitutes the “oil reservoir fuel temperature control means”, and the feed pump This eliminates the need for driving means such as the above, and can reduce the cost of the DME fuel supply device 100 for diesel engines.

Referring to Fig. 33, after the diesel engine is stopped, the cylinder is filled with the depleted DME fuel to prevent the abnormal combustion such as knocking that occurs when the cylinder is moved. Then, the DME fuel filled in the oil reservoir 11, the injection pipe 3, the nozzle return pipe 7, and the cooling medium supply pipe 51 is recovered to the fuel tank 4 by “residual fuel recovery means”. The “fuel recovery means” is composed of a three-way solenoid valve 21 (communication path switching means) and an electric compressor 23. When the three-way solenoid valve 21 is turned off after the diesel engine is stopped, the motor is activated. DME fuel filled by the compressor 23 into the oil sump 11, the injection pipe 3, the nozzle return pipe 7, and the cooling medium supply pipe 51 flows along the path indicated by the symbol J. The DME fuel that is recovered by turning off the return path switching solenoid valve 122 is turned off in the first return path (the path indicated by symbol H). After being cooled by the cooler 1, it is collected in the fuel tank 4.

Next, the procedure of the DME fuel temperature control according to the present invention, which is executed by the DME fuel temperature control unit 10, will be described.

FIG. 34 is a flowchart showing the “procedure for controlling the temperature in the fuel tank” according to the present invention. Note that the procedure shown in the flowchart is repeatedly executed at regular intervals while the power of the diesel engine vehicle equipped with the DME fuel supply device 100 is ON. This is the procedure to be performed.

First, it is determined whether or not the diesel engine is operating (Step s: if the Do diesel engine is not operating (No in Step S1), the return path switching solenoid valve 122 is turned off and the procedure is terminated. (Step S5) On the other hand, if the diesel engine is operating (Yes in Step S1), then the “temperature control means in the fuel tank” is controlled to reduce the amount of DME fuel in the fuel tank 4. Execute the procedure to adjust the temperature, where Tg is the temperature of the DME fuel in the oil reservoir 11 detected by the oil reservoir temperature sensor 1 la and Tg is the fuel tank detected by the fuel tank temperature sensor 4 c. The temperature of the DME fuel in 4 is Tt, and the lower limit of the temperature difference between the DME fuel in 1 and the DME fuel in the fuel tank 4 where the required pressure difference is obtained is Tt≤T g In other words, the temperature of the DME fuel in the fuel tank 4 is determined. Gallery you determine temperature below whether or not the lower limit value a obtained by adding the temperature difference required temperature of the DME fuel in 1 1 (step S 2).

If the temperature of the DME fuel in the fuel tank 4 is lower than the temperature of the DME fuel in the oil reservoir 11 plus the lower limit of the required temperature difference (Y es in step S2), If the temperature difference between the DME fuel in the chamber 11 and the DME fuel in the fuel tank 4 is less than the lower limit of the required temperature difference, the return path switching solenoid valve 122 is turned on to control the fuel tank. The DME fuel sent to 4 is returned to the fuel tank 4 via the second return path, that is, without passing through the cooler 42 (step S3). Since the DME fuel delivered to the fuel tank 4 is returned to the fuel tank 4 without cooling, the temperature of the DME fuel in the fuel tank 4 increases. As a result, the temperature difference between the DME fuel in the oil reservoir 11 and the DME fuel in the fuel tank 4 increases, so that the DME fuel in the oil reservoir 11 and the DME fuel in the fuel tank 4 increase. The temperature difference between the temperature difference and the required temperature difference can be higher than the lower limit of the required temperature difference.

After the return path switching solenoid valve 122 is 電磁 N controlled, or the temperature of the DME fuel in the fuel tank 4 adds the required temperature difference to the temperature of the DME fuel in the oil reservoir 11 If the temperature is equal to or higher than the specified temperature (No in step S2), Determine whether or not. ? Is the upper limit of the temperature difference between the DME fuel in the oil reservoir 11 and the DME fuel in the fuel tank 4 where the required pressure difference is obtained. That is, it is determined whether the temperature of the DME fuel in the fuel tank 4 is equal to or higher than the temperature obtained by adding the upper limit value ^ of the required temperature difference to the temperature of the DME fuel in the oil reservoir 11 (step S4). .

If the temperature of the DME fuel in the fuel tank 4 is lower than the temperature obtained by adding the upper limit of the required temperature difference /? To the temperature of the DME fuel in the oil reservoir 11 (No in step S4), return as it is. The procedure is terminated while maintaining the control state of the path switching solenoid valve 122. On the other hand, if the temperature of the DME fuel in the fuel tank 4 is equal to or higher than the temperature obtained by adding the upper limit value /? Of the required temperature difference to the temperature of the DME fuel in the oil reservoir 11 (Yes in step S4), If the temperature difference between the DME fuel in the oil reservoir 11 and the DME fuel in the fuel tank 4 is equal to or more than the upper limit value of the required temperature difference ζβ, the return path switching solenoid valve 122 is turned off. The DME fuel sent to the fuel tank 4 by the F control is returned to the fuel tank 4 via the first return path, that is, via the cooler 42, and the procedure is terminated (step S5). Since the DME fuel sent to the fuel tank 4 is cooled and returned to the fuel tank 4, the temperature of the DME fuel in the fuel tank 4 decreases. As a result, the temperature difference between the DME fuel in the oil reservoir 11 and the DME fuel in the fuel tank 4 becomes smaller, so that the difference between the DME fuel in the oil reservoir 11 and the DME fuel in the fuel tank 4: The temperature difference can be less than the required upper limit of the temperature difference of 3. In this manner, the temperature difference between the DME fuel in the oil reservoir 11 and the DME fuel in the fuel tank 4 can be controlled to be equal to or more than the required lower limit and less than the upper limit / ?.

FIG. 35 is a flowchart showing an “oil reservoir fuel temperature control procedure” according to the present invention. Note that the procedure shown in the flowchart is a procedure that is repeatedly executed at regular intervals while the power of the diesel engine vehicle equipped with the DME fuel supply device 100 is ON.

First, it is determined whether or not the diesel engine is operating (step S11). Day If the diesel engine is not operating (No in Step S11), the cooling medium supply pipe opening / closing solenoid valve 16 is turned off (control), and the procedure is terminated (Step S16). On the other hand, if the diesel engine is operating (Yes in step S11), the “oil sump fuel temperature adjusting means” is controlled, and the temperature of the DME fuel in the oil sump 11 reaches the specified temperature. The temperature of the DME fuel in the oil sump 11 is adjusted so that First, Tg≤T _G - whether §, i.e., DME fuel temperature limit width of the gallery 11 to the temperature specified temperature TG of DM E fuel oil reservoir 11 - or below the temperature obtained by adding a § It is determined whether or not it is (step S12).

If the temperature of the DME fuel in the oil chamber 11 is lower than the specified temperature _Tc plus the lower limit width of the DME fuel temperature in the oil chamber 11 (Yes in step S12), If the temperature of the DME fuel in the chamber 11 is lower than the lower limit temperature of the DME fuel in the oil chamber 11, there is no need to cool the DME fuel in the oil chamber 11, so the cooling medium supply pipe opening and closing electromagnetic Turn ON (close control) the valve 16 (step S13). As a result, the DME fuel as the cooling medium is not supplied to the oil reservoir fuel cooler 106, so that the DME fuel in the oil reservoir 11 is not cooled. Therefore, the temperature of the DME fuel in the oil reservoir 11 rises and becomes equal to or higher than the lower limit temperature of the DME fuel in the oil reservoir 11. After the cooling medium supply pipe opening / closing solenoid valve 16 is subjected to 〇N control, or if the temperature of the DME fuel in the oil reservoir 11 is equal to or higher than the lower limit temperature of the DME fuel in the oil reservoir 11 (step S12). No), the followed,. Tg≥T _G + 7 whether, that is, the upper width + § of DME fuel temperature of the DME fuel in the oil reservoir 11 in the fuel gallery 11 to the specified temperature T _G It is determined whether or not the temperature is equal to or higher than the value obtained by adding (Step S14).

If the temperature of the DME fuel in the oil reservoir 11 is defined temperature T ₀ in the oil reservoir chamber temperature less than that obtained by adding the upper limit width + § of DME fuel temperature within 11 (vo at step S 14), the oil reservoir 1 1 Since there is no need to cool the DME fuel inside, the cooling medium supply pipe is closed and the ON control state of the solenoid valve 16 is maintained, and the procedure is terminated. On the other hand, the temperature of the DME fuel in the oil sump 11 rises to the specified temperature _{π π} ; If the temperature of the DME fuel in the oil reservoir 11 is equal to or higher than the upper limit temperature of the DME fuel in the oil reservoir 11 if the temperature is equal to or higher than the temperature obtained by adding the Since it is necessary to cool the DME fuel inside, the cooling medium supply pipe opening / closing solenoid valve 16 is turned off (closed control) and the procedure is terminated (step S15). As a result, the DME fuel as a cooling medium is supplied to the oil reservoir fuel cooler 106, so that the DME fuel in the oil reservoir 11 is cooled, and the temperature of the DME fuel in the oil reservoir 11 decreases. However, the temperature becomes lower than the upper limit temperature of the DME fuel in the oil reservoir 11. Therefore, the temperature of the DME fuel in the oil reservoir 11 can be controlled within the specified temperature T _G ± a. FIG. 36 is a graph schematically showing a temperature waveform of the DME fuel in the fuel tank 4 and a temperature waveform of the DME fuel in the oil reservoir 11 according to the present invention.

As described above, the temperature (Tt) of the DME fuel in the fuel tank 4 controlled by the “temperature control procedure in the fuel tank” is within the range of Tg + H ≦ Tt and Tg +? The temperature (Tg) of the DME fuel in the oil reservoir 11 controlled by the “oil reservoir fuel temperature control procedure” is in the range of T _G — 7≤Tg and T _G + a.

In this way, the temperature of the DME fuel in the fuel tank 4 is controlled so that the temperature difference between the DME fuel in the oil reservoir 11 and the DME fuel in the fuel tank 4 becomes relatively constant. Accordingly, the DME fuel can be supplied from the fuel tank 4 to the oil reservoir 11 at a substantially constant delivery pressure without using a driving means such as a feed pump. In addition, since the temperature of the DME fuel in the oil reservoir 11 can be controlled to a substantially constant temperature, the DME fuel injection characteristics of the injection pump 1 can be stabilized.

Further, as another embodiment, in the DME fuel supply device 100 shown in the above embodiment, the supply amount of the cooling medium to the oil reservoir One that regulates the temperature of the DME fuel. FIG. 37 is a schematic configuration diagram showing another embodiment of the DME fuel supply device 100 according to the present invention. The electric compressor 23 is driven by a rotary driving power source such as a DC motor, The suction force is increased or decreased by increasing or decreasing the number of rotations of the rotational driving force source. The DME fuel supply device 100 is configured so that the rotation speed of the electric compressor 13 can be controlled by the DME fuel temperature control unit 10. Note that other configurations are the same as those of the DME fuel supply device 100 shown in FIG. 29, and thus description thereof is omitted.

FIG. 38 is a flowchart showing the “oil reservoir fuel temperature control procedure” in the DME fuel supply device 100 for a diesel engine shown in FIG. 37. The procedure shown in the flowchart is a procedure that is repeatedly executed at regular intervals while the power of the diesel engine vehicle equipped with the DME fuel supply device 100 is ON. First, it is determined whether or not the diesel engine is operating (step S 2 l). If the diesel engine is not operating (No in step S 21), the electric compressor 23 is controlled to OFF to perform the procedure. Is completed (step S24). On the other hand, if the diesel engine is operating (Yes in step S21), the “oil sump fuel temperature control means” is controlled, and the temperature of the DME fuel in the oil sump 11 reaches the specified temperature. The temperature of the DME fuel in the oil reservoir 11 is adjusted so as to reach _TG . First, it is determined whether or not Tg> T _Q , that is, whether or not the temperature of the DME fuel in the oil reservoir 11 exceeds the specified temperature _TG (step S22).

The temperature of the DME fuel in the oil sump 11 is the specified temperature. If it does not exceed (in step S22), it is not necessary to cool the DME fuel in the oil reservoir 11 so that the electric compressor 23 is controlled to OFF and the procedure is terminated (step S24). . On the other hand, if the temperature of the DME fuel in the sump 11 exceeds the specified temperature _TG (Yes in step S22), the DME fuel in the sump 11 needs to be cooled. The electric compressor 23 is turned ON at a rotation speed corresponding to the temperature difference between the temperature of the DME fuel in the chamber 11 and the specified temperature _TG (step S23). As a result, the DME fuel as a cooling medium is supplied to the oil reservoir fuel cooler 106 at a supply amount corresponding to the temperature difference between the temperature of the DME fuel in the oil reservoir 11 and the specified temperature Τ _Γτ. So in the oil sump 11 DME fuel temperature can be adjusted with high precision.

The procedure for adjusting the temperature of the DME fuel in the fuel tank 4 by the “control procedure for the temperature in the fuel tank” is the same as that in the flowchart shown in FIG. FIG. 39 is a graph schematically showing the temperature waveform of the DME fuel in the fuel tank 4 and the temperature waveform of the DME fuel in the oil reservoir 11 according to the present invention, wherein the rotation speed of the electric compressor 23 is shown. FIG. 3 shows the temperature control of the DME fuel in the oil reservoir 11 by controlling the temperature.

As described above, the temperature (Tt) of the DME fuel in the fuel tank 4 controlled by the “temperature control procedure in the fuel tank” becomes a temperature within the range of Tg + «≤Tt and Tg +? temperature of DME fuel in the "gallery fuel temperature control procedure" oil reservoir 11 which is controlled by a (Tg) of, T _G - the temperature in the 7≤Tg rather a range of T _G + §. Also, as compared with the above-described embodiment in which the temperature of the DME fuel in the oil reservoir 11 is controlled by the ONZOFF control of the cooling medium supply pipe opening / closing solenoid valve 16, the cooling medium supplied to the oil reservoir fuel cooler 106 is By adjusting the supply amount of the DME fuel, the temperature of the DME fuel in the oil reservoir 11 can be adjusted with higher precision as shown in the figure.

Further, as another embodiment, the DME fuel supply device 100 in the above embodiment is a common rail type. In the common rail type DME fuel supply device 100 in which the DME fuel pressure-fed from the injection pump 1 is supplied via a common rail to which each fuel injection nozzle 9 is connected, the DME fuel is supplied from the oil reservoir 11 to the common rail. Since the temperature of the DME fuel can be controlled to be substantially constant, the temperature of the DME fuel in the common rail can be controlled to be substantially constant. Therefore, the present invention is also applicable to the common rail type DME fuel supply device 100, and the operation and effect of the present invention can be obtained.

It should be noted that the present invention is not limited to the above embodiments, and various modifications are possible within the scope of the invention described in the claims, and these are also included in the scope of the present invention. Needless to say. According to the ninth embodiment of the present invention, DME fuel can be supplied from the fuel tank to the oil reservoir of the injection pump without using a driving means such as a feed pump. It is possible to provide a diesel engine DME fuel supply device capable of obtaining a stable fuel injection characteristic of a pump. Industrial applicability

According to the present invention, in a DME fuel supply device for a diesel engine, DME fuel can be supplied from a fuel tank to an oil reservoir of an injection pump without using a drive means such as a feed pump. Also, stable fuel injection characteristics of the injection pump can be obtained.

Claims

The scope of the claims

1. DME fuel supplied from the fuel tank via the feed pipe is sent out to the injection pipe connected to the fuel injection nozzle of the diesel engine by a predetermined amount at a predetermined evening. Chillon pump,

A nozzle return pipe for returning the DME fuel overflowing from the fuel injection nozzle to the feed pipe;

An oil sump fuel cooling system for cooling the DME fuel in the oil sump of the injection pump;

An oil sump fuel temperature detecting means for detecting a temperature of the DME fuel in the oil sump; and a temperature of the DME fuel in the oil sump in the fuel sump by the oil sump fuel cooling device. A configuration in which the DME fuel in the fuel tank is supplied to the oil reservoir by a pressure difference between the inside of the oil reservoir and the inside of the fuel tank caused by adjusting the temperature to a temperature lower than the temperature of the fuel. Diesel Djinn fuel supply system.

2. The oil reservoir fuel cooling device according to claim 1, wherein the DME fuel in the oil reservoir is cooled by a cooling cycle using the DME fuel as a refrigerant. A DME fuel supply device for a diesel engine, comprising: a fuel cooler that cools the DME fuel in the oil reservoir using heat of vaporization caused by gasification.

3. The fuel cooling device according to claim 2, wherein the oil reservoir fuel cooling device includes: a refrigerant supply pipe that supplies the DME fuel from the feed pipe; and the DME fuel that flows through the refrigerant supply pipe. A refrigerant supply pipe opening / closing solenoid valve for opening / closing the refrigerant supply pipe. The diesel fuel supply system of Diesel-Zhengjing, wherein the DME fuel supply system is configured to be controlled by controlling opening and closing of a valve.

4. The DME fuel according to claim 3, which is mixed with lubricating oil in a power chamber of the engine pump, which is a dedicated lubrication system separated from the lubrication system of the diesel engine. An oil separator, and an electric compressor that pressurizes the DME fuel separated at the oil separator and sends the pressurized DME fuel to the fuel tank. The electric compressor is supplied from the refrigerant supply pipe to the oil reservoir fuel cooling device. The DME fuel supply device for a diesel engine, wherein the DME fuel is sent to the fuel tank by the electric compressor.

5. The DME fuel supply for a diesel engine according to claim 4, further comprising a fuel tank temperature adjusting means for adjusting the temperature inside the fuel tank.

6. The fuel tank according to claim 5, wherein the temperature control means in the fuel tank sends the DME fuel sent from the electric compressor to the fuel tank after being cooled via an air-cooled cooler. A first return path, wherein the DME fuel sent from the electric compressor is sent to the fuel tank without passing through the air-cooled cooler, and a first return path; A return path switching solenoid valve for switching between a return path and the second return path; and a fuel tank temperature detecting means for detecting a temperature inside the fuel tank, wherein the return path includes: A DME fuel supply device for diesel engines, characterized in that the switching solenoid valve is controlled to adjust the temperature in the fuel tank.

7. The method according to any one of claims 1 to 6, wherein after stopping the diesel engine, The diesel engine according to claim 1, further comprising: a residual fuel recovery unit configured to recover the DME fuel remaining in the oil reservoir of the injection pump and the nozzle return pipe to the fuel tank. D ME fuel supply.

8. In claim 7, the residual fuel recovery means is configured to connect an inlet side of the oil reservoir chamber communicating with the feed pipe and a communication path of the nozzle return pipe with the feed pipe from the feed pipe to the electric compressor. Communication path switching means for switching to a residual fuel recovery pipe communicating with the inlet side, wherein the DME fuel remaining in the oil reservoir of the injection pump and in the nozzle return pipe is supplied by the electric compressor. A DME fuel supply device for a diesel engine, wherein the DME fuel supply device is configured to be collected in the fuel tank.

9. In claim 8, the communication between the liquid phase portion of the fuel tank and the feed pipe is cut off, and the gas phase portion of the fuel tank is communicated with the feed pipe to remove the gaseous DME fuel. The DME fuel supply device according to claim 1, wherein the DME fuel supply device is provided with a gas-phase fuel delivery means for delivering.

10. The diesel engine according to any one of claims 1 to 9, wherein a sub-fuel tank having a smaller capacity than the fuel tank is provided between the fuel tank and the feed pipe. In some cases, the communication between the fuel tank and the sub fuel tank is cut off, and the gas phase of the sub fuel tank is connected to the outlet side of the electric compressor so that the electric compressor allows the air to be compressed by the electric compressor. The DME fuel supply device for a diesel engine, wherein the DME fuel is supplied to the oil reservoir from the sub fuel tank whose phase is pressurized.

11. The structure according to any one of claims 1 to 10, wherein the DME fuel sent from the injection pump is supplied to a common rail, and is sent from the common rail to each fuel injection nozzle. DME fuel supply system for diesel engines.

1 2. Injection pump that sends out DME fuel supplied from the fuel tank via the feed pipe to the injection pipe communicating with the fuel injection nozzle of the diesel engine by a predetermined amount at a predetermined timing. When,

An oil reservoir fuel cooling means for cooling the DME fuel in the oil reservoir of the injection pump by cooling a cam chamber of the injection pump; and detecting a temperature of the DME fuel in the oil reservoir. An oil sump fuel temperature detecting means, and the oil sump generated by adjusting the temperature of the DME fuel in the oil sump chamber to a temperature lower than the temperature of the DME fuel in the fuel tank by the oil sump fuel cooling means. A DME fuel supply device for a diesel engine, wherein the DME fuel in the fuel tank is supplied to the oil reservoir by a pressure difference between the chamber and the fuel tank. .

13. The fuel reservoir according to claim 12, wherein the oil reservoir fuel cooling means cools the cam chamber using heat of vaporization caused by vaporization of the DME fuel. DME fuel supply system for diesel engines.

14. In Claim 13, the oil reservoir fuel cooling means comprises: a refrigerant supply pipe for supplying the DME fuel from the feed pipe; and a DME fuel flowing to the refrigerant supply pipe. A fuel supply device that discharges the fuel into the cam chamber; And a refrigerant supply pipe opening / closing solenoid valve for opening and closing the coolant supply pipe. The diesel engine has a structure controlled by opening and closing the refrigerant supply pipe opening / closing electromagnetic valve. ME fuel supply device.

15. The oil separator according to claim 14, wherein the oil separator separates the DME fuel mixed in the lubricating oil in the cam chamber, which is a dedicated lubrication system separated from the lubrication system of the diesel engine. An electric compressor that pressurizes the DME fuel separated at night and sends it to the fuel tank.

16. The DME fuel for a diesel engine according to claim 15, further comprising a temperature adjusting means in the fuel tank for adjusting the temperature in the fuel tank.

17. The fuel tank according to claim 16, wherein the temperature control means in the fuel tank is supplied to the fuel tank after the DME fuel sent from the electric compressor is cooled via an air-cooled cooler. A first return path, wherein the DME fuel sent from the electric compressor is sent to the fuel tank without passing through the air-cooled cooler; a first return path; A return path switching electromagnetic valve for switching between a second return path and a fuel tank internal temperature detecting means for detecting a temperature in the fuel tank, for controlling the return path switching electromagnetic valve; A DME fuel supply device for a diesel engine, wherein the DME fuel supply device is configured to adjust the temperature in the fuel tank.

18. The fuel pump according to any one of claims 12 to 17, wherein after stopping the diesel engine, the oil reservoir of the injection pump and the nozzle pipe are connected. A DME fuel supply device for a diesel engine, comprising: a residual fuel recovery means capable of recovering the DME fuel remaining in the fuel tank to the fuel tank.

19. The method according to claim 18, wherein the residual fuel recovery means is configured to connect an inlet side of the oil reservoir chamber communicating with the feed pipe and a communication path of the nozzle return pipe from the feed pipe to the electric compressor. Communication path switching means for switching to a residual fuel recovery pipe communicating with the inlet side of the fuel pump, wherein the DME fuel remaining in the oil sump chamber of the injection pump and the nozzle return pipe is A DME fuel supply device for a diesel engine, wherein the DME fuel supply device is configured to be recovered to the fuel tank by the electric compressor.

20. The gaseous DME fuel according to claim 19, wherein communication between a liquid phase portion of the fuel tank and the feed pipe is interrupted, and a gas phase portion of the fuel tank is communicated with the feed pipe. A DME fuel supply device according to claim 1, wherein the DME fuel supply device includes gas-phase fuel delivery means for delivering fuel.

21. The diesel engine according to any one of claims 12 to 20, wherein a sub-fuel tank having a smaller capacity than the fuel tank is provided between the fuel tank and the feed pipe. At the time of start-up, the communication between the fuel tank and the sub-fuel tank is cut off, and the gas compressor of the sub-fuel tank and the outlet side of the electric compressor are connected to each other, so that the electric compressor is The DME fuel supply device for a diesel engine, wherein the DME fuel is supplied to the oil reservoir from the sub fuel tank whose gas phase is pressurized by one.

22. The injection bone according to any one of claims 12 to 21. Wherein the DME fuel delivered from the pump is supplied to a common rail, and is delivered to each fuel injection nozzle from the common rail.

2 3. DME fuel supplied from the fuel tank via the feed pipe is sent out to the injection pipe communicating with the fuel injection nozzle of the diesel engine by a predetermined amount at a predetermined evening. An injection pump; an oil reservoir for adjusting the temperature of the DME fuel filled in the oil reservoir of the injection pump; a fuel temperature adjusting means; and a fuel tank for adjusting the temperature of the DME fuel in the fuel tank. A method for controlling the temperature of DME fuel in a diesel fuel supply system in Diesel-Zenjing comprising:

As the temperature of the DME fuel in the oil reservoir chamber is defined temperature T _e, and controls the oil reservoir chamber fuel temperature adjusting means, and, DME fuel in the fuel evening the tank than the temperature of the DME fuel in the oil reservoir chamber Controlling the temperature control means in the fuel tank so that the temperature of the fuel becomes high with a relatively constant temperature difference.

24.In Claim 23, the oil sump fuel temperature adjusting means comprises: an oil sump fuel cooler that cools the DME fuel in the oil sump using the degassed DME fuel as a cooling medium; A cooling medium supply means for supplying the DME fuel in the fuel tank as a cooling medium to the oil reservoir fuel cooler; and an oil reservoir fuel temperature detecting means for detecting a temperature of the DME fuel in the oil reservoir. ,

The cooling medium described above, based on the temperature of the DME fuel in the oil chamber detected by the oil chamber fuel temperature detecting means, such that the temperature of the DME fuel in the oil chamber becomes the specified temperature _TG. A method for controlling the temperature of the DME fuel, wherein the supply operation of the cooling medium by the supply means is controlled by 0 N / 0 FF.

25. The fuel tank according to claim 23, wherein the oil chamber fuel temperature adjusting means cools the DME fuel in the oil chamber using the vaporized DME fuel as a cooling medium, and the fuel tank. Cooling medium supply means for supplying the DME fuel in the oil reservoir as a cooling medium to the oil reservoir fuel cooler, and oil reservoir fuel temperature detecting means for detecting the temperature of the DME fuel in the oil reservoir.

Based on the temperature of the DME fuel in the oil chamber detected by the oil chamber fuel temperature detecting means, the temperature of the DME fuel in the oil chamber is the specified temperature T. Adjusting the supply amount of the cooling medium by the cooling medium supply means so as to obtain a temperature of the DME fuel.

26. The cooling medium supply means according to claim 25, wherein a supply amount of the cooling medium to the oil reservoir fuel cooler is increased or decreased according to a rotation speed of a rotary driving force source. The rotational driving force so that the temperature of the DME fuel in the oil reservoir becomes the specified temperature T cj based on the temperature of the DME fuel in the oil reservoir detected by the oil reservoir fuel temperature detecting means. A method for controlling the temperature of DME fuel, comprising controlling the number of revolutions of a source.

27. The fuel tank according to any one of claims 23 to 26, wherein the temperature control means in the fuel tank is provided after the DME fuel delivered to the fuel tank is cooled via an air-cooled cooler. A first return path for returning to the fuel tank; a second return path for returning the DME fuel to the fuel tank to the fuel tank without passing through the air-cooled cooler; Return path switching means for switching between a first return path and the second return path, and fuel tank fuel temperature detecting means for detecting the temperature of the DME fuel in the fuel tank,

DME fuel in the fuel tank detected by the fuel tank fuel temperature detecting means Controlling the return path switching means such that the temperature of the DME fuel in the fuel tank becomes relatively higher than the temperature of the DME fuel in the oil reservoir with a relatively constant temperature difference based on the temperature of the oil reservoir. DME fuel temperature control method.

2 8. Injection that sends DME fuel supplied from the fuel tank via the feed pipe to the injection pipe communicating with the fuel injection nozzle of the diesel engine by a predetermined amount at a predetermined evening. A pump, an oil reservoir for adjusting the temperature of the DME fuel filled in the oil reservoir of the injection pump, a fuel temperature adjusting means, and a fuel reservoir for adjusting the temperature of the DME fuel in the fuel reservoir. A DME fuel supply device for a diesel engine, comprising: an internal temperature control unit; and a DME fuel temperature control unit that controls the oil reservoir fuel temperature control unit and the fuel tank internal temperature control unit,

Wherein D ME fuel temperature control means, as the temperature of the D ME fuel in the oil reservoir chamber is defined temperature T _Q, and controls the oil reservoir chamber fuel temperature adjusting means, and the DME fuel in the oil reservoir chamber Controlling the temperature control means in the fuel tank such that the temperature of the DME fuel in the fuel tank becomes relatively higher than the temperature with a relatively constant temperature difference. apparatus.

29. The fuel tank according to claim 28, wherein the oil reservoir fuel temperature adjusting means cools the DME fuel in the oil reservoir using the vaporized DME fuel as a cooling medium, and the fuel tank. Cooling medium supply means for supplying the DME fuel in the oil reservoir as a cooling medium to the oil reservoir fuel cooler, and oil reservoir fuel temperature detecting means for detecting the temperature of the DME fuel in the oil reservoir.

The DME fuel temperature control means adjusts the temperature of the DME fuel in the oil reservoir to the specified temperature based on the temperature of the DME fuel in the oil reservoir detected by the oil chamber fuel temperature detection means. supply of the cooling medium by the cooling medium supply means so as to be _α DME fuel supply system for diesel engines, characterized in that the operation is controlled by ONZOFF.

30. The oil reservoir fuel temperature controller according to claim 28, wherein the oil reservoir fuel temperature adjusting means cools the DME fuel in the oil reservoir using the vaporized DME fuel as a cooling medium, and the fuel tank. A cooling medium supply means for supplying the DME fuel in the oil reservoir as a cooling medium to the oil reservoir fuel cooler; and an oil reservoir fuel temperature detecting means for detecting a temperature of the DME fuel in the oil reservoir.

The DME fuel temperature control means, based on the temperature of the DME fuel in the oil sump detected by the oil sump fuel temperature detection means, adjusts the temperature of the DME fuel in the oil sump to the specified temperature T. A DME fuel supply device for a diesel engine, wherein the supply amount of the cooling medium by the cooling medium supply means is adjusted so as to be e.

31. In Claim 30, the cooling medium supply means is configured to increase or decrease the supply amount of the cooling medium to the oil reservoir fuel cooler according to the number of rotations of a rotary driving force source. The oil reservoir fuel temperature control means determines the temperature of the DME fuel in the oil reservoir based on the temperature of the DME fuel in the oil reservoir detected by the oil reservoir fuel temperature detection means. as the temperature T _Q, wherein a means for controlling the rotational speed of the rotary driving power source and, D ME fuel supply device for a diesel engine characterized in that.

32. The fuel tank according to any one of claims 28 to 31, wherein the temperature control means in the fuel tank is provided after the DME fuel delivered to the fuel tank is cooled via an air-cooled cooler. A first return path for returning to the fuel tank; a second return path for returning the DME fuel to the fuel tank to the fuel tank without passing through the air-cooled cooler; Return path switching means for switching between a first return path and the second return path; and the DME fuel in the fuel tank. Fuel temperature detection means for detecting the temperature of the fuel tank,

The DME fuel temperature control means, based on the temperature of the DME fuel in the fuel tank detected by the fuel tank fuel temperature detection means, calculates the temperature of the DME fuel in the oil storage chamber from the fuel tank. Controlling the return path switching means so that the temperature of the DME fuel in the inside becomes high with a relatively constant temperature difference.

33. The structure according to any one of claims 28 to 32, wherein the DME fuel delivered from the injection pump is supplied to a common rail, and is delivered from the common rail to each fuel injection nozzle. A DME fuel supply system for diesel engines.

3 4. An injector that sends out a predetermined amount of DME fuel supplied from the fuel tank via the feed pipe to the injection pipe connected to the fuel injection nozzle of the diesel engine at a predetermined timing. A fuel pump for adjusting the temperature of the DME fuel filled in the oil reservoir of the injection pump; a fuel temperature adjusting means for adjusting the temperature of the DME fuel; and a fuel tank for adjusting the temperature of the DME fuel in the fuel tank. A DME fuel temperature control program for causing a computer to execute the DME fuel temperature control in the DME fuel supply device having a temperature control means.

An oil reservoir fuel temperature control procedure for controlling the oil reservoir fuel temperature adjusting means so that the temperature of the DME fuel in the oil reservoir becomes a specified temperature T; And a fuel tank temperature control procedure for controlling the fuel tank temperature control means so that the temperature of the DME fuel in the tank becomes relatively high with a substantially constant temperature difference. DME fuel temperature control program.

35. The oil reservoir fuel cooler according to claim 34, wherein the oil reservoir fuel temperature adjusting means is configured to cool the DME fuel in the oil reservoir using the degassed DME fuel as a cooling medium, Cooling medium supply means for supplying DME fuel in the fuel tank as a cooling medium to the oil reservoir fuel cooler; and oil reservoir fuel temperature detection means for detecting the temperature of the DME fuel in the oil reservoir. Prepared,

The oil reservoir fuel temperature control procedure includes: determining a temperature of the DME fuel in the oil reservoir based on the temperature of the DME fuel in the oil reservoir detected by the oil reservoir fuel temperature detecting means; A temperature control program for DME fuel, characterized by comprising a procedure of ONZOFF control of a supply operation of the cooling medium by the cooling medium supply means so as to be Te.

36. The oil reservoir fuel cooler according to claim 34, wherein the oil reservoir fuel temperature adjusting means cools the DME fuel in the oil reservoir using the degassed DME fuel as a cooling medium. A cooling medium supply means for supplying the DME fuel in the fuel tank as a cooling medium to the oil reservoir fuel cooler; and an oil reservoir fuel temperature detecting means for detecting a temperature of the DME fuel in the oil reservoir. ,

The oil reservoir fuel temperature control procedure includes: determining a temperature of the DME fuel in the oil reservoir based on the temperature of the DME fuel in the oil reservoir detected by the oil reservoir fuel temperature detecting means; T. A temperature control program for the DME fuel, comprising a step of adjusting a supply amount of the cooling medium by the cooling medium supply means so that

37. In Claim 36, the cooling medium supply means is configured to increase or decrease the supply amount of the cooling medium to the oil reservoir fuel cooler according to the number of rotations of a rotary driving force source. The oil reservoir fuel temperature control procedure includes: determining a temperature of the DME fuel in the oil reservoir based on a temperature of the DME fuel in the oil reservoir detected by the oil reservoir fuel temperature detecting means. As the temperature is the predetermined temperature T _Q, the temperature control program of the a procedure for controlling the rotational speed of the rotary driving power source and, D ME fuel characterized by.

38. The fuel tank according to any one of claims 34 to 37, wherein the temperature control means in the fuel tank is provided after the DME fuel delivered to the fuel tank is cooled via an air-cooled cooler. A first return path to return to the fuel tank; and a second return path to return the DME fuel to the fuel tank to the fuel tank without passing through the air-cooled cooler. Return path switching means for switching between the first return path and the second return path, and fuel tank fuel temperature detecting means for detecting the temperature of the DME fuel in the fuel tank. ,

The temperature control process in the fuel tank is based on the temperature of the DME fuel in the fuel tank detected by the fuel tank fuel temperature detecting means, based on the temperature of the DME fuel in the oil reservoir. A program for controlling the temperature of the DME fuel, characterized by comprising a procedure for controlling the return path switching means so that the temperature of the DME fuel in the fuel tank becomes relatively high with a relatively constant temperature difference.