JP2014129789A - Fuel injection connection device adaptable for multi-fuel, fuel injection system using connection device and method for connection with connection device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a connection device facilitating modification from the conventional fuel injection system to a fuel injection system adaptable for multi-fuel having a main fuel system and a sub-fuel system.SOLUTION: A fuel injection valve system connection part 17 of a fuel injection connection device 10 comprising a main body 14 having a main fuel flow passage 11, a sub-fuel flow passage 12 and a confluence flow passage 13; a main fuel system connection part 15 connected to a main fuel piping 21; a sub-fuel system connection part 16 connected to a sub-fuel piping 31; and a fuel injection valve system connection part 17 connected to a fuel injection valve 40 is formed in the same connection structure as that of the main fuel system connection part 15 and enables the conventional main fuel piping 21 to be connected. The sub-fuel system connection part 16 is formed in different structure from the fuel injection valve system connection part 17 and the main fuel system connection part 15 so as not to enable an erroneous connection of the sub-fuel piping 31 to a connection part other than the sub-fuel system connection part 16.

Description

  The present invention is connected to a fuel injection system that injects fuel into a cylinder of an internal combustion engine, and is connected to a fuel injection system that can handle various types of fuels with a streamlined connection, a fuel injection system using the connection device, And a connection method using the connection device.

  There is a need for an internal combustion engine that can be operated with various types of fuel and a fuel injection device used in such an internal combustion engine. For example, it has been proposed to use lower quality petroleum-based fuels and biofuels. Fuels have different ignitability depending on the species, and in order to be able to operate with various types of fuel, it is necessary to cope with fuels with poor ignitability.

  In the case of using a fuel with poor ignitability, a technology is known in which a fuel with better ignitability than this fuel is injected first, ignited, and this fuel is used as a fire type to burn fuel with poor ignitability (see below, patents) Reference 1).

  Moreover, the structure which provides the common fuel injection nozzle for controlling the fuel injection of the 1st fuel and the 2nd fuel in a combustion chamber is disclosed (refer the following patent document 2).

  In addition, in a configuration in which a common fuel injection nozzle is provided by the first fuel injection pump and the second fuel injection pump, a T-type pipe joint of an injection pipe connecting the two fuel injection pumps and the fuel injection nozzle is disclosed ( See Patent Document 3 below).

JP-A-6-159182 Japanese Patent Laid-Open No. 5-26127 Japanese Utility Model Publication No. 5-61453

  When the main fuel system and the sub fuel system are connected in a common fuel injection nozzle as in Patent Document 1 and Patent Document 2 described above, there is a drawback that the configuration of the fuel injection system becomes complicated, and the fuel injection nozzle The complicated structure of connecting the fuel injection nozzle to the cylinder of the internal combustion engine also requires special consideration. Furthermore, it is necessary to use a special fuel injection nozzle.

  Further, as in Patent Document 3 described above, when the first fuel injection pump, the second fuel injection pump, and the fuel injection nozzle are connected by an injection pipe using a T-type pipe joint, the T-type pipe joint is a fuel injection. Since it is connected to the pump and not attached to the fuel injection nozzle, the joining portion of the first fuel and the second fuel is long. In addition, since the fuel discharge valve port of the second fuel injection pump and the outlet of the T-type pipe joint are not formed equally in terms of connection structure and dimensions, the existing injection pipe cannot be used. Furthermore, since the fuel discharge valve port of the first fuel injection pump and the outlet of the T-type fitting are substantially equal and are not considered to differ in connection structure or dimensions, there is a possibility of erroneous connection, for example, a screw There is a defect that damages the part and causes loss of connection man-hours.

  An object of the present invention is to provide a connection device that facilitates modification from a conventional fuel injection system to a fuel injection system that can handle various fuels having two main and sub fuel systems.

  A fuel injection connecting device corresponding to various fuels according to claim 1 is a fuel injection connecting device connected to a fuel injection valve for injecting fuel into a cylinder of an internal combustion engine. A main body having a fuel flow path, a sub fuel flow path through which the sub fuel flows, a merge flow path through which the main fuel and the sub fuel flow, and the main body connected to a main fuel pipe for supplying the main fuel A main fuel system connection portion provided at an end of the main fuel flow path, and a sub fuel pipe connected to a sub fuel pipe for supplying the sub fuel via a sub fuel injection valve for injecting the sub fuel. An auxiliary fuel system connection provided at an end of the fuel flow path; and a fuel injection valve system connection provided at an end of the merging flow path of the main body connected to the fuel injection valve. A valve system connection portion is formed in a connection structure equal to the main fuel system connection portion, and the sub fuel system is formed. By forming with different connection part to connect the structural and the fuel injection valve based connections and the main fuel system connection unit may connect the main fuel piping to the main fuel system connection. Further, by forming the auxiliary fuel system connection portion different from the connection structure of the fuel injection valve system connection portion and the main fuel system connection portion, the auxiliary fuel pipe is connected to the fuel injection valve system connection portion, or the auxiliary fuel piping is provided. Cannot be connected to the main fuel system connection. Note that “equal in connection structure” means that, for example, a connection structure having the same outer shape, such as a connection structure between flanges, of course, can be fitted even if the outer shape looks different, such as the relationship between male and female screws. It is possible to include those that can be connected to each other, and those that have different external shapes but can form a flow path through which fuel flows as a function.

  According to a second aspect of the present invention, there is provided a fuel injection connecting device capable of dealing with various fuels, wherein the main fuel flow path is provided with a main fuel flow path check valve for preventing a back flow of the fuel. The main fuel flow path check valve allows the fuel to flow through the fuel injection valve without flowing back through the main fuel flow path when the auxiliary fuel is injected. Here, the fuel flowing through the fuel injection valve may be a fuel in which main fuel and sub fuel are mixed, in the case where the main fuel is the main component, and in some cases, the sub fuel is the main component. Further, when the main fuel and the sub fuel are the same type of fuel, they may be different types of fuel. As a case where the main fuel and the auxiliary fuel are different types of fuel, for example, the auxiliary fuel may be a fuel having a higher cetane number than the main fuel. For example, the main fuel may be heavy oil and the secondary fuel may be light oil.

  According to a third aspect of the present invention, there is provided a fuel injection connecting device capable of handling various fuels, comprising a sub fuel injection valve for injecting the sub fuel into the sub fuel flow path. By providing this auxiliary fuel injection valve in the fuel injection connecting device, the connecting device for fuel injection and the auxiliary fuel injection valve are configured integrally, so there is no need to separately provide the auxiliary fuel injection valve in the middle of the auxiliary fuel piping. The construction can be completed at once. Moreover, since it was comprised integrally, the sub fuel flow path after a sub fuel injection valve can be shortened.

  Further, in the fuel injection connecting device that can handle various fuels according to claim 4, the connecting portion of the auxiliary fuel injection valve also serves as the auxiliary fuel system connecting portion. Since the connecting portion of the auxiliary fuel injection valve also serves as the auxiliary fuel system connecting portion, it is not necessary to separately provide the auxiliary fuel system connecting portion.

  According to a fifth aspect of the present invention, there is provided a fuel injection connecting apparatus capable of handling various fuels, wherein the sub fuel injection valve is formed at an angle between the main fuel flow path and the flow direction of the main fuel and the sub fuel. Are connected at an angle of less than 90 degrees. That is, by connecting the auxiliary fuel injection valves obliquely, the joining portion can be brought close to the fuel injection valve system connecting portion, and the joining flow path can be shortened. Further, by connecting the auxiliary fuel injection valve obliquely, the auxiliary fuel system connection portion can be moved away from the fuel injection valve system connection portion and the fuel injection valve, and the space around the auxiliary fuel system connection portion can be widened.

  According to a sixth aspect of the present invention, there is provided a fuel injection connecting device capable of handling various fuels, wherein the auxiliary fuel flow path is formed in the main body in parallel with the main fuel flow path. The merging portion is provided in the vicinity of the fuel injection valve system connection portion so that the length of the merging passage is shorter than the length of the main fuel passage or the sub fuel passage. The junction between the sub fuel channel and the main fuel channel can be close to the fuel injection valve, and the junction channel can be shortened.

  According to a seventh aspect of the present invention, there is provided a fuel injection connecting device capable of handling various fuels, wherein the valve body of the main fuel check valve faces the downstream side of the main fuel flow path and biases the valve body. The biasing means is structured to face the upstream side of the valve body. In other words, an urging means for urging the valve body is arranged upstream of the main fuel system check valve so that a space for housing the urging means is unnecessary on the downstream side of the valve body. The volume of the pressed portion can be reduced. As the biasing means, for example, a spring, a magnetic force, an elastomer, or the like can be used.

  In addition, a fuel injection connecting device that can handle various fuels according to claim 8 includes a sub fuel flow path check valve that prevents back flow of the fuel in the sub fuel flow path. That is, when the pressure of the main fuel becomes larger than the pressure of the auxiliary fuel, the auxiliary fuel flow path check valve prevents the fuel from flowing back through the auxiliary fuel flow path, and the fuel flows to the fuel injection valve. It becomes.

  According to a ninth aspect of the present invention, there is provided a fuel injection system using a fuel injection connecting device capable of handling various fuels, comprising: a high-pressure pump that supplies the auxiliary fuel at a high pressure; and a common rail that stores the high-pressure auxiliary fuel. ing. That is, the high-pressure auxiliary fuel pressurized by the high-pressure pump can be stored in the common rail and supplied into the cylinder of the internal combustion engine. For example, sub-injection such as pre-injection and after-injection can control the injection timing, injection period (injection amount), injection pressure, etc. with higher accuracy than the main fuel system by using an auxiliary fuel system including a common rail. It becomes.

  According to a tenth aspect of the present invention, there is provided a fuel injection system using a fuel injection connecting device that can handle various fuels, and prevents back flow of the fuel when the pressure of the auxiliary fuel becomes lower than the pressure of the main fuel. A system check valve is provided in the auxiliary fuel pipe between the common rail and the auxiliary fuel system connection portion. For example, when a high-pressure pump without a check valve is used or when the check valve of the high-pressure pump is damaged, this system check valve prevents back flow of fuel even if the auxiliary fuel injection valve is not completely closed It becomes possible to do.

  A connecting method using a fuel injection connecting device capable of handling various fuels according to claim 11 is the main fuel pipe connected to the fuel injection valve for supplying the main fuel into the cylinder of the internal combustion engine. , Step 2 for attaching the fuel injection valve system connection portion of the fuel injection connection device to the fuel injection valve, and removing the main fuel pipe from the main fuel system connection of the fuel injection connection device. A step 3 for connecting to the part, and a step 4 for connecting the auxiliary fuel pipe to the auxiliary fuel system connecting part of the fuel injection connecting device. By performing Step 1 to Step 4 using this connecting device, it is possible to change the conventional fuel injection system to a fuel injection system that can handle various fuels having a main fuel system and a sub fuel system. Thereby, it is possible to connect the auxiliary fuel system connection part and the main fuel system connection part without making a mistake.

  According to a twelfth aspect of the present invention, there is provided a connecting method using a fuel injection connecting device that can handle various fuels, and includes a step 5 of connecting the common rail to the auxiliary fuel pipe. The fuel injection connecting device and the common rail can be individually connected. For example, the common rail can be connected later on site.

  A main fuel channel, a sub fuel channel, a main body having a merging channel, a main fuel system connection part of the main body connected to the main fuel pipe, and a sub fuel pipe through a sub fuel injection valve for injecting sub fuel And a fuel injection valve system connection portion of the main body connected to the fuel injection valve, and the fuel injection valve system connection portion is equal in structure to the main fuel system connection portion. By forming, a fuel injection valve can be connected to a fuel injection valve system connection part, and a main fuel piping can be connected to a main fuel system connection part. Further, by forming the auxiliary fuel system connection portion different from the connection structure of the fuel injection valve system connection portion and the main fuel system connection portion, the auxiliary fuel pipe is connected to the fuel injection valve system connection portion, or the auxiliary fuel piping is provided. Since it cannot be connected to the main fuel system connection portion, erroneous connection at the time of pipe connection can be prevented, and modification from the conventional fuel injection system can be performed efficiently and easily. Further, for example, since an existing fuel injection valve can be used, it is not necessary to use special fuel injection valves or special considerations regarding the connection of the fuel injection valves to the cylinders. In addition, when a secondary fuel system is retrofitted, it can be easily applied not only to a new main engine and a new ship but also to an existing main engine and an existing ship.

  By providing a main fuel flow path check valve that prevents back flow of fuel in the main fuel flow path, fuel flows into the fuel injection valve without flowing back through the main fuel flow path when the auxiliary fuel is injected. It becomes. Since the backflow of the fuel to the main fuel flow path is prevented, a decrease in the fuel pressure is suppressed, and the fuel injection pressure can be increased by injecting the auxiliary fuel. In addition, since there is no backflow of fuel, there is no need to control the amount of secondary fuel injected in consideration of the backflow, and the accuracy of the amount of fuel injected during fuel injection control of the secondary fuel can be improved. It is possible to perform fuel injection control so as to sufficiently improve the characteristics.

  By providing the auxiliary fuel injection valve for injecting auxiliary fuel into the auxiliary fuel flow path, the fuel injection connecting device and the auxiliary fuel injection valve can be configured integrally, so that the construction can be completed easily at one time. In addition, since the auxiliary fuel injection valve is eliminated in the middle of the auxiliary fuel pipe, the piping work is facilitated. Further, since the auxiliary fuel injection valve is integrated, the auxiliary fuel flow path after the auxiliary fuel injection valve can be shortened, the volume of the portion controlled by pressurization by injection of the auxiliary fuel is reduced, and a small amount of auxiliary fuel is injected. Therefore, the responsiveness of the fuel injection control and the accuracy of the injection amount control can be improved. For this reason, it is possible to inject auxiliary fuel and control the injection timing, injection period (injection amount), injection pressure, etc. with high accuracy. For example, it is possible to improve engine efficiency and improve exhaust gas characteristics. It is possible to control the fuel injection so that it can be sufficiently increased.

  Since the connecting portion of the auxiliary fuel injection valve also serves as the auxiliary fuel system connecting portion, it is not necessary to separately provide the auxiliary fuel system connecting portion. For this reason, for example, the space around the auxiliary fuel system connection portion can be widened, the number of man-hours for construction can be reduced, and attachment work is facilitated.

  By connecting the auxiliary fuel injection valve to the main fuel flow path at an angle of less than 90 degrees between the flow direction of the main fuel and the auxiliary fuel, the junction can be brought closer to the fuel injection valve system connection. The confluence channel can be shortened. For this reason, the volume of the portion controlled by pressurizing by injection of sub fuel can be reduced, and control can be performed by injection of a small amount of sub fuel, so that the responsiveness of fuel injection control can be improved and fuel injection can be performed with high accuracy. It becomes. As a result, for example, fuel injection can be performed by injecting a small amount of auxiliary fuel, and the amount of auxiliary fuel supplied can be reduced, so that the auxiliary fuel supply system can be made smaller. Further, by connecting the auxiliary fuel injection valve obliquely, the auxiliary fuel system connection portion can be moved away from the fuel injection valve system connection portion and the fuel injection valve, and the space around the auxiliary fuel system connection portion can be widened. Thereby, piping work becomes easy.

  The auxiliary fuel flow path is formed in the main body in parallel with the main fuel flow path, the junction with the main fuel flow path is in the vicinity of the fuel injection valve system connection portion, and the length of the merge flow path is the main fuel flow path or By providing it so as to be shorter than the auxiliary fuel flow path, the merging portion of the auxiliary fuel flow path and the main fuel flow path can be brought closer to the fuel injection valve system connection portion, and by shortening the merging flow path, the auxiliary fuel flow path can be reduced. It is possible to reduce the volume of the pressurized portion by injecting the fuel and to inject the fuel with high accuracy. Further, since the merging flow path is shortened, the main fuel and the auxiliary fuel can be exchanged quickly. For example, when the fuel injected from the fuel injection valve is switched from the main fuel to the auxiliary fuel, the injection amount of the auxiliary fuel decreases as the merge flow path becomes shorter. Thus, for example, it is possible to perform fuel injection by controlling the fuel injected from the fuel injection valve as sub fuel, main fuel, and sub fuel.

  By adopting a structure in which the valve body of the main fuel check valve faces the downstream side of the main fuel flow path and the biasing means for biasing the valve body faces the upstream side of the valve body, the downstream side of the valve body Since the space for storing the biasing means is unnecessary, the volume of the portion pressurized by the injection of the auxiliary fuel is reduced, and the fuel pressure can be increased and the response can be improved to inject the fuel. It becomes possible. As a result, for example, atomization of fuel spray and diversification of the injection pattern can be performed, good combustion can be realized, and exhaust gas can be improved.

  By providing the auxiliary fuel flow path check valve for preventing the reverse flow of the fuel in the auxiliary fuel flow path, it is possible to prevent the fuel from flowing back through the auxiliary fuel flow path when the pressure of the main fuel becomes higher than the pressure of the auxiliary fuel. This can prevent the fuel from flowing into the fuel injection valve. Since the backflow of fuel is prevented, the fuel injection amount can be easily controlled. As a result, for example, engine efficiency and exhaust gas characteristics can be improved efficiently.

  By providing a high-pressure pump that supplies auxiliary fuel at a high pressure and a common rail that stores high-pressure auxiliary fuel, the high-pressure auxiliary fuel pressurized by the high-pressure pump is stored at a high pressure in the common rail and stably stored in the cylinder of the internal combustion engine. For example, it is possible to atomize the fuel spray and diversify the injection pattern, realize good combustion, and improve the exhaust gas.

  By providing a system check valve in the sub fuel pipe between the common rail and the sub fuel system connection portion to prevent the back flow of the fuel when the pressure of the sub fuel becomes lower than the pressure of the main fuel, for example, the check valve This system check valve prevents fuel backflow and worsens fuel injection when a high-pressure pump without air pressure is used or when the check valve of the high-pressure pump is damaged and the auxiliary fuel injection valve is not fully closed. It is possible to keep good without.

  Step 1 for removing a main fuel pipe connected to a fuel injection valve for supplying main fuel into a cylinder of an internal combustion engine, Step 2 for attaching a fuel injection valve system connection portion of a fuel injection connecting device to the fuel injection valve, and removal Step 3 for connecting the main fuel pipe to the main fuel system connection portion of the connecting device for fuel injection, and Step 4 for connecting the sub fuel pipe to the sub fuel system connecting portion of the fuel injection connecting device. As a result, the conventional fuel injection system can be changed efficiently and easily without erroneous connection from the fuel injection system having the main fuel system and the sub fuel system. Furthermore, since an existing fuel injection valve can be used, it is not necessary to take special considerations regarding connection of a special fuel injection valve or a fuel injection valve to a cylinder. Since the auxiliary fuel system is only installed afterward, it can be easily applied not only to new main engines and new ships but also to existing main engines and existing ships.

  By providing the step 5 of connecting the common rail to the auxiliary fuel pipe, the fuel injection connecting device and the common rail can be individually connected. For example, since the common rail can be retrofitted at the site, the connection work can be easily performed according to the space at the site.

1 is a conceptual diagram of a fuel injection system using a fuel injection connecting device according to a first embodiment of the present invention. It is a conceptual diagram of the fuel-injection system using the connection apparatus for fuel injection in 2nd embodiment of this invention. It is a conceptual diagram of the fuel-injection system using the connection apparatus for fuel injection in 3rd embodiment of this invention. It is a conceptual diagram of the fuel-injection system using the connection apparatus for fuel injection in 4th embodiment of this invention. It is a conceptual diagram of the fuel-injection system using the connection apparatus for fuel injection in 5th embodiment of this invention. It is a conceptual diagram of the fuel-injection system using the connection apparatus for fuel injection in 6th embodiment of this invention.

  Hereinafter, first to sixth embodiments of the present invention will be described with reference to FIGS.

  FIG. 1 is a conceptual diagram of a fuel injection system using a fuel injection connecting device 10 according to a first embodiment of the present invention. This fuel injection system includes a fuel injection connecting device 10, a main fuel supply system 20, a sub fuel supply system 30, and a fuel injection valve 40 that injects fuel into a cylinder 50. The fuel injection connecting device 10 includes a main body 14 having a merging flow path 13 that flows through a main fuel flow path 11 through which main fuel flows and a sub fuel flow path 12 through which sub fuel flows, and a main fuel pipe that supplies the main fuel. The main fuel system connection portion 15 provided at the end of the main fuel flow path 11 of the main body 14 connected to the main body 14, and the end of the sub fuel flow path 12 of the main body 14 connected to the sub fuel pipe 31 for supplying the sub fuel. And a fuel injection valve system connection portion 17 provided at the end of the merging flow path 13 of the main body 14 connected to the fuel injection valve 40. In this embodiment, the main fuel flow path check valve 18 for preventing the back flow of fuel is provided in the main fuel flow path 11 of the main body 14. In the auxiliary fuel supply system 30, a high-pressure pump 33, a common rail 34, and an auxiliary fuel injection valve 19 are provided. The fuel injection valve system connection portion 17 of the fuel injection connection device 10 is formed in the same structure as the main fuel system connection portion 15 to connect the main fuel pipe 21. Note that “equal in connection structure” means that, for example, a connection structure having the same outer shape, such as a connection structure between flanges, of course, can be fitted even if the outer shape looks different, such as the relationship between male and female screws. It is possible to include those that can be connected to each other, and those that have different external shapes but can form a flow path through which fuel flows as a function. When the fuel injection valve system connection portion 17 has a screw structure, the main fuel system connection portion 15 is a screw having the same connection structure paired with the main fuel system connection portion 15 and has the same dimensions such as a screw diameter and a screw pitch. It forms so that it may become. Further, the auxiliary fuel system connection portion 16 is formed to be different from the fuel injection valve system connection portion 17 and the main fuel system connection portion 15 in terms of connection structure, so that the auxiliary fuel pipe 31 is connected to the fuel injection valve system connection portion 17. Alternatively, the auxiliary fuel pipe 31 cannot be connected to the main fuel system connection portion 15 and erroneous connection is prevented. For example, when the fuel injection valve system connection portion 17 has a screw structure, the auxiliary fuel system connection portion 16 is a fastening means that does not have a screw structure, or the screw diameter or the screw pitch is dimensionally different even in the screw structure. So that it cannot be connected.

The operation of the fuel injection system configured as described above will be described.
In the main fuel supply system 20, the main fuel stored in the main fuel tank 22 is pressurized and sent by a mechanical fuel injection pump 23, and fuel is supplied via the main fuel pipe 21 and the fuel injection connecting device 10. It is sent to the injection valve 40. The fuel injection valve 40 has a valve that opens the flow path by the pressure of the fuel, and the fuel is injected when the pressure of the fuel by the mechanical fuel injection pump 23 exceeds a predetermined value (injection start pressure). The injected fuel spreads in the cylinder 50 as fine particles (droplets), and self-ignites and burns when the temperature in the cylinder 50 rises due to compression by the piston. In the main fuel supply system 20, fuel is pressurized every time the plunger is stroked by the cam. That is, for each fuel injection, the fuel required at that time is pressurized by the mechanical fuel injection pump 23. Since the fuel must be pressurized, delivered, and injected in accordance with the fuel injection timing (timing) of each cylinder 50, the mechanical fuel injection pump 23 is provided independently for each cylinder 50.

  In the auxiliary fuel supply system 30, the auxiliary fuel stored in the auxiliary fuel tank 32 is pressurized and sent out by the high-pressure pump 33 and stored in the common rail 34 in a high pressure state. A sub fuel injection valve 19 is provided on the way from the common rail 34 to the fuel injection connecting device 10 via the sub fuel pipe 31. When the auxiliary fuel injection valve 19 is opened, the fuel stored in the common rail 34 is sent to the fuel injection valve 40 via the fuel injection connecting device 10 and is injected into the cylinder 50 from here. The high-pressure pump 33 and the common rail 34 are provided in common for all cylinders 50 or a plurality of cylinders 50, and the auxiliary fuel injection valve 19 and the fuel injection connecting device 10 are provided for each cylinder 50.

  By electrically controlling the auxiliary fuel injection valve 19, the introduction of the common rail 34 system for an automobile having this configuration becomes easier. Further, by adopting the electric control type, the fuel injection timing, the fuel injection period (injection amount), the fuel injection pattern, and the like can be controlled by electric signals, and the degree of freedom of control is expanded. Further, in ships, load fluctuations related to the wave period may occur due to the influence of waves, but this can be suitably dealt with by adopting an electric control system with a high degree of freedom of control.

  As described above, in the main fuel supply system 20, fuel pressurization is performed independently for each fuel injection, whereas in the sub fuel supply system 30, the fuel is pre-pressurized and pressurized. The fuel that has been stored in a pressurized state and has been pressurized in advance at the timing of fuel injection is supplied. In the main fuel supply system 20, the pressure is low at the initial stage of fuel injection, and the fuel particles injected are relatively large. On the other hand, in the auxiliary fuel supply system 30, since the fuel is pressurized in advance, it can be injected at a high pressure from the beginning of the injection period, and the fuel particles become finer.

  In this embodiment, the main fuel flow path check valve 18 for preventing the back flow of fuel is provided in the main fuel flow path 11 of the main body 14. The main fuel flow path check valve 18 prevents the fuel from flowing back through the main fuel flow path 11. For this reason, even when the fuel in the main fuel supply system 20 is not pressurized, the fuel flows into the fuel injection valve 40 without backflowing the main fuel flow path 11 when the auxiliary fuel is injected. The injected sub fuel increases the pressure of the fuel in the fuel injection valve 40, and the fuel is injected when the injection start pressure is exceeded. By injecting this auxiliary fuel, it becomes possible to increase the injection pressure and perform various injections, and it is possible to sufficiently improve the engine efficiency and improve the exhaust gas characteristics. Further, by providing the main fuel check valve 18, the engine can be safely operated only by the auxiliary fuel supply system 30 when the main fuel supply system 20 has a problem. In this embodiment, the delivery valve type check valve has a stem with a groove around the periphery, but a ball and a spring 18b may be used in combination.

  In the case of a new engine of a new shipbuilding, when remodeling from a conventional injection system to a fuel injection system that can handle various fuels having main and sub fuel systems, the fuel injection connection device 10 is used to efficiently and easily remodel the engine. It becomes possible. At this time, the conventional fuel injection valve 40 and the conventional main fuel pipe 21 can be used. There is no need to give special consideration to the connection of the fuel injection valve 40 to the special fuel injection valve 40 or the cylinder 50. In the case of an existing ship's existing engine, when remodeling from a conventional injection system to a fuel injection system compatible with various fuels having main and sub fuel systems, the existing fuel injection valve 40 and the existing main fuel are further added. It is possible to use the piping 21. Since the auxiliary fuel supply system 30 is only installed afterward, it can be easily applied to existing ships. Further, even if it is necessary to return to the original state for some reason, it is possible to easily restore the state where the auxiliary fuel supply system 30 is removed using the existing main fuel pipe 21.

  Furthermore, the connection work is facilitated by the following four-step connection method using the fuel injection connection device 10. Step 1 of removing the main fuel pipe 21 connected to the fuel injection valve 40 for supplying the main fuel into the cylinder 50 of the internal combustion engine, the fuel injection valve system connection portion 17 of the fuel injection connection device 10 capable of dealing with various fuels. Step 2 for attaching to the fuel injection valve 40, Step 3 for connecting the removed main fuel pipe 21 to the main fuel system connection portion 15 of the connection device 10 for fuel injection, Sub-system connection to the sub fuel system connection portion 16 of the fuel injection connection device 10 Step 4 is to connect the fuel pipe 31. Thereby, the sub fuel system connection part 16 and the main fuel system connection part 15 can be connected without making a mistake. By performing steps 1 to 4 using the fuel injection connecting device 10, it is possible to efficiently and easily change from a conventional fuel injection system to a fuel injection system having a main fuel system and a sub fuel system. . Since the existing fuel injection valve 40 can be used, it is not necessary to consider special considerations regarding the connection of the fuel injection valve 40 to the special fuel injection valve 40 or the cylinder 50. Note that since the auxiliary fuel supply system 30 is only installed afterward, it can be easily applied not only to a new main engine and a new ship but also to an existing main engine and an existing ship.

  In addition to Step 1 to Step 4 described above, Step 5 for connecting the common rail 34 to the auxiliary fuel pipe 31 is provided, and the fuel injection connecting device 10 and the common rail 34 can be individually connected. Since the common rail 34 can be connected later on site, the connection work can be easily performed according to the space of the site.

  FIG. 2 is a conceptual diagram of a fuel injection system using the fuel injection connecting device 10 according to the second embodiment of the present invention. The same components as those of the first embodiment already described are assigned the same numbers, and detailed descriptions thereof are omitted. In the present embodiment, an auxiliary fuel injection valve 19 for injecting auxiliary fuel into the auxiliary fuel flow path 12 is provided and integrated. Further, in the connection of the auxiliary fuel injection valve 19, a connection structure different from that of the first embodiment is used. The main body 14 has a structure that can be fitted to connect the auxiliary fuel injection valve 19 to the auxiliary fuel flow path 12. The auxiliary fuel injection valve 19 is fitted into the main body 14, a pusher is applied behind the auxiliary fuel injection valve 19, the pusher and the main body 14 are connected with bolts, and the auxiliary fuel injection valve 19 is sandwiched therebetween. The connection structure is fixed.

  In the present embodiment, since the auxiliary fuel injection valve 19 is fixed to the main body 14, it can be handled as a unit. As an effect, by providing the auxiliary fuel injection valve 19 for injecting auxiliary fuel into the auxiliary fuel flow path 12, the connecting device for fuel injection 10 and the auxiliary fuel injection valve 19 can be configured integrally, so that construction can be easily performed at once. Can be completed. Further, by integrally configuring the fuel injection connecting device 10 and the auxiliary fuel injection valve 19, there is a high possibility that the entire device can be reduced in size.

  Further, it is not necessary to separately provide the auxiliary fuel injection valve 19 in the middle of the auxiliary fuel pipe 31, so that the space can be increased accordingly, and the number of piping steps can be reduced and the piping work can be facilitated.

  Further, since the auxiliary fuel injection valve 19 is integrally formed, the auxiliary fuel flow path 12 after the auxiliary fuel injection valve 19 can be shortened, the volume of the portion controlled by pressurization by injection of the auxiliary fuel is reduced, and a small amount of the auxiliary fuel injection valve 19 is formed. Since it can be controlled by fuel injection, the responsiveness of the fuel injection control and the accuracy of the injection amount control can be improved. By injecting auxiliary fuel, it becomes possible to control the injection timing, injection period (injection amount), injection pressure, etc. with high accuracy. For example, the efficiency of the engine is improved and the effect of improving exhaust gas characteristics is sufficiently improved. Thus, fuel injection control can be performed. Furthermore, if the inlet of the auxiliary fuel injection valve 19 is attached in contact with the main fuel flow path 11 and the merge flow path 13, the auxiliary fuel flow path 12 can be made extremely short, and further, the portion controlled by pressurization by the injection of auxiliary fuel. Since the volume is reduced, the above-described effects are increased.

  In the present embodiment, the connecting portion of the auxiliary fuel injection valve 19 also serves as the auxiliary fuel system connecting portion 16. For this reason, it is not necessary to provide the auxiliary fuel system connection part 16 separately, the number of man-hours for construction can be reduced, and attachment work becomes easy. In the present embodiment, high-pressure fuel is used for the operation of the auxiliary fuel injection valve 19, and this fuel returns to the auxiliary fuel tank 32 through the return pipe 36.

  FIG. 3 is a conceptual diagram of a fuel injection system using the fuel injection connecting device 10 according to the third embodiment of the present invention. The same components as those of the first and second embodiments already described are given the same numbers, and detailed descriptions thereof are omitted. In the present embodiment, the auxiliary fuel injection valve 19 is connected to the main fuel flow path 11 at an angle of less than 90 degrees formed by the flow direction of the main fuel and the auxiliary fuel.

  By connecting the auxiliary fuel injection valve 19 obliquely to the main fuel flow path 11 in this way, the merging portion can be brought closer to the fuel injection valve system connection portion 17 and the merging flow path 13 can be shortened. For this reason, the volume of the portion controlled by pressurizing by injection of sub fuel can be reduced, and control can be performed by injection of a small amount of sub fuel, so that the responsiveness of fuel injection control can be improved and fuel injection can be performed with high accuracy. It becomes. Thereby, it becomes possible to control thermal efficiency and exhaust gas characteristics, and it is possible to improve efficiency and improve exhaust gas characteristics.

  Further, by connecting the auxiliary fuel injection valve 19 at an angle, the auxiliary fuel system connection portion 16 can be moved away from the fuel injection valve system connection portion 17 and the fuel injection valve 40, and the space around the auxiliary fuel system connection portion 16 is widened. can do. Thereby, piping work becomes easy.

  Further, by connecting the auxiliary fuel injection valve 19 to the main fuel flow path 11 so that the angle formed by the flow directions of the main fuel and the auxiliary fuel is less than 90 degrees, the flow resistance is reduced and energy loss is reduced. Less. Further, since the fuel flow is not disturbed, the accuracy of the fuel injection amount is increased, and the fuel injection can be easily controlled.

  Furthermore, since the injection amount of the auxiliary fuel can be suppressed to the minimum necessary, the components of the auxiliary fuel supply system 30 such as the high pressure pump 33 and the common rail 34 can be suppressed to be small, and the cost can be reduced.

  FIG. 4 is a conceptual diagram of a fuel injection system using the fuel injection connecting device 10 according to the fourth embodiment of the present invention. The same components as those of the first to third embodiments already described are assigned the same numbers, and detailed descriptions thereof are omitted. In the present embodiment, the auxiliary fuel flow path 12 is formed in the main body 14 in parallel with the main fuel flow path 11, and the junction with the main fuel flow path 11 is set in the vicinity of the fuel injection valve system connection portion 17. Yes.

  By bringing the merging portion closer to the fuel injection valve system connecting portion 17, shortening the merging flow path 13, and reducing the volume of the portion pressurized by the injection of the auxiliary fuel, the fuel pressure is increased and its responsiveness (acceleration is increased). (Pressure speed) can be expected to improve.

  Further, when the joining portion of the auxiliary fuel and the main fuel is close to the fuel injection valve 40, the fuel is exchanged quickly, and the control of the fuel injection by changing the fuel type becomes easy. For example, by controlling the fuel injected from the fuel injection valve 40 as sub fuel, main fuel, and sub fuel so that the sub fuel is more ignitable and combustible than the main fuel, fuel injection is performed. Efficiency and exhaust gas characteristics can be improved. For this reason, it is important to shorten the merging channel 13, and it is preferable to make the length of the merging channel 13 shorter than the length of the main fuel channel 11 or the auxiliary fuel channel 12.

  Also, when the main fuel and the auxiliary fuel are high in viscosity, and the temperature of each fuel is adjusted to be merged and injected into the fuel, there is a portion where the main fuel and the auxiliary fuel flow in close proximity, The temperature difference between the main fuel and the sub fuel is reduced, the temperature unevenness after joining is reduced, and the temperature adjustment of the fuel becomes easy.

  FIG. 5 is a conceptual diagram of a fuel injection system using the fuel injection connecting device 10 in the fifth embodiment of the present invention. The same components as those of the first to fourth embodiments already described are assigned the same numbers, and detailed descriptions thereof are omitted. In the present embodiment, the valve body 18a of the main fuel flow path check valve 18 is installed on the downstream side of the main fuel flow path 11, and the spring 18b that biases the valve body 18a is installed on the upstream side of the valve body 18a. It has a structure to do. The stem of the valve body 18a is fixed through a valve guide 18 which is a hole provided in the center of the valve receiver 18c, through a spring 18b which is a biasing means, and an end of the stem is fixed by a spring receiver 18d. The end of the stem and the spring receiver 18d are fixed by a set screw or a cotter. The stem portion of the valve body 18a has a structure with a groove through which fuel passes.

  In this way, the valve body 18a of the main fuel check valve 18 faces the downstream side of the main fuel flow path 11, and the spring 18b that biases the valve body 18a faces the upstream side of the valve body 18a. This eliminates the need for a space for housing the spring 18b on the downstream side of the valve body 18a, so that the volume pressurized by the injection of the auxiliary fuel is reduced, and the fuel pressure is increased and its response (pressurization speed) is reduced. Improvement can be expected. Although it is important to reduce the volume of the pipe from the valve body 18a of the main fuel flow path check valve 18 to the hole of the fuel injection valve 40 as much as possible, the main fuel flow path check valve 18 in FIGS. In comparison, it can be expected that the fuel pressure is increased and the responsiveness (pressurization speed) is improved because the volume of the spring 18b is reduced. By increasing the pressure of fuel injection and quickly performing fuel injection such as pre-injection by injecting secondary fuel, the effect of improving efficiency and improving exhaust gas characteristics is increased. In the present embodiment, the spring 18b is used as the urging means. However, a magnetic force or an elastomer other than the spring 18b may be used as the urging means.

  FIG. 6 is a conceptual diagram of a fuel injection system using the fuel injection connecting device 10 in the sixth embodiment of the present invention. The same components as those of the first to fifth embodiments already described are assigned the same numbers, and detailed descriptions thereof are omitted. This fuel injection system includes an auxiliary fuel flow path check valve 12b for preventing a reverse flow of fuel in the auxiliary fuel flow path 12. Further, a pressure adjusting valve 37 for adjusting the pressure of the common rail 34 and a system check valve 38 for preventing a back flow of the fuel when the pressure of the auxiliary fuel becomes lower than the pressure of the main fuel are provided.

  The present embodiment is a fuel injection system including a fuel injection connecting device 10, a high-pressure pump 33 that supplies auxiliary fuel at a high pressure, and a common rail 34 that stores high-pressure auxiliary fuel. The high-pressure auxiliary fuel pressurized by the high-pressure pump 33 is stored in the common rail 34 at a high pressure, is stably supplied into the cylinder 50 of the internal combustion engine, and sub-injection such as pre-injection and after-injection is supplied to the common rail 34. Using the system 30, it is possible to control the injection timing, injection time (injection amount), injection pressure and the like with higher accuracy than the main fuel supply system 20. Further, the pressure of the common rail 34 can be changed. In the present embodiment, a pressure adjusting valve 37 is provided on the return path for returning the auxiliary fuel from the common rail 34 to the auxiliary fuel tank 32, and the pressure that the pressure adjusting valve 37 opens is changed to adjust the pressure in the common rail 34. Yes. That is, the pressure regulating valve 37 has a structure in which the electromagnetic valve is opened / closed by turning on / off the energization in order to adjust the pressure in the common rail 34 to a set pressure. For safety, when the energization is off, the solenoid valve is open and the pressure is not increased. That is, when the pressure in the common rail 34 is higher than the set pressure, the solenoid valve of the pressure adjustment valve 37 is turned off, the solenoid valve is opened, and the fuel in the common rail 34 is released to reduce the pressure for adjustment. It has become. If the pressure in the common rail 34 is lower than the set pressure, the solenoid valve of the pressure regulating valve 37 is turned on and the solenoid valve is closed to increase the pressure by collecting high-pressure fuel from the high-pressure pump 33. To adjust. When an electric pump is used as the high-pressure pump 33, the pressure of the common rail 34 can be adjusted by changing the rotational speed of the motor that drives the pump. Further, the pressure may be adjusted on the pump side by changing the oil feed amount of the high-pressure pump 33 or the like.

  In the present embodiment, the auxiliary fuel flow path 12 is provided with a secondary fuel flow path check valve 12b that prevents back flow of fuel. The sub fuel flow check valve 12b prevents the fuel from flowing back through the sub fuel flow channel 12 when the pressure of the main fuel becomes larger than the pressure of the sub fuel. When the pre-injection is performed by setting the pressure of the auxiliary fuel in the common rail 34 lower than the maximum injection pressure of the main injection, the pressure of the main fuel may be larger than the pressure of the auxiliary fuel. In this case, by preventing the backflow, the main injection by the main fuel can be performed quickly and at a high pressure, and the engine efficiency can be improved and the exhaust gas can be improved.

  In addition, when a malfunction occurs in the auxiliary fuel supply system 30 for some reason, the pressure of the main fuel becomes larger than the pressure of the auxiliary fuel, and the main fuel flows back not only to the fuel injection valve 40 but also to the auxiliary fuel supply system 30. End up. Even in such a case, by providing the auxiliary fuel flow path check valve 12b, the backflow of fuel to the auxiliary fuel supply system 30 and the like can be prevented, and the engine operation by the normal mechanical fuel injection pump 23 becomes possible. .

  Further, in the present embodiment, the system check valve 38 that prevents the back flow of the fuel when the pressure of the auxiliary fuel becomes lower than the pressure of the main fuel is provided with the auxiliary fuel between the common rail 34 and the auxiliary fuel system connection portion 16. The pipe 31 is provided. Since the role of the system check valve 38 is substantially the same as that of the auxiliary fuel flow path check valve 12b, only one of them may be provided. Both may be provided in consideration of the occurrence of problems in either. The auxiliary fuel flow path check valve 12b needs to be installed inside the fuel injection connecting device 10, and when it is difficult to install spatially, the auxiliary fuel flow path check valve 12b is installed by installing the system check valve 38. The same effect as the stop valve 12b can be obtained.

  Without these check valves, when the pressure of the main fuel becomes larger than the pressure of the auxiliary fuel, the fuel flows back through the auxiliary fuel flow path 12 and flows back through the auxiliary fuel pipe 31. Since the high pressure pump 33 is provided with a normal check valve, it does not flow back, but the pressure adjustment valve 37 functions as a check valve when energized, so when the pressure adjustment valve 37 is not energized, The fuel will flow backward. Even in such a case, by providing the check valve, the backflow of fuel to the auxiliary fuel supply system 30 and the like can be prevented, and the engine operation by the normal mechanical fuel injection pump 23 becomes possible. Further, it is possible to prevent the main fuel from flowing into the auxiliary fuel tank 32 and mixing. In the present embodiment, the return pipe 36 in the auxiliary fuel injection valve 19 is a pipe for returning the high pressure auxiliary fuel used for operating the auxiliary fuel injection valve 19 to the auxiliary fuel tank 32. If 19 is not operated, the fuel does not flow backward and does not flow to the auxiliary fuel tank 32.

  In the first to sixth embodiments, the positions of the main fuel system connection portion 15 and the sub fuel system connection portion 16 can be changed due to the restriction of the mounting location. Also in this case, by forming the auxiliary fuel system connection portion 16 different from the fuel injection valve system connection portion 17 and the main fuel system connection portion 15 in terms of connection structure or dimensions, erroneous connection can be prevented. Remodeling from the fuel injection system can be performed efficiently and easily. Further, depending on the restriction of the mounting location, the merged shape of the main fuel flow path 11 and the auxiliary fuel flow path 12 of the fuel injection connecting device 10 may be merged into, for example, T type or Y type. .

  Further, when it is difficult to attach the fuel injection connecting device 10 due to space, a connection pipe may be provided between the fuel injection connecting device 10 and the fuel injection valve 40.

  In the above embodiment, although it demonstrated in relation to the diesel engine for ships, this invention is applicable also to other moving bodies, for example, internal combustion engines, such as a rail vehicle and a motor vehicle. The present invention can also be applied to an engine (such as a direct injection type Otto engine) that performs intermittent combustion other than a diesel engine.

DESCRIPTION OF SYMBOLS 10 Fuel injection connection apparatus 11 Main fuel flow path 12 Sub fuel flow path 12b Sub fuel flow path check valve 13 Merge flow path 14 Main body 15 Main fuel system connection part 16 Sub fuel system connection part 17 Fuel injection valve system connection part 18 Main fuel flow path check valve 18a Valve body 18b Spring 18c Valve receiver 18d Spring receiver 19 Sub fuel injection valve 20 Main fuel supply system 21 Main fuel pipe 30 Sub fuel supply system 31 Sub fuel pipe 33 High pressure pump 34 Common rail 37 Pressure adjustment valve 38 System Check Valve 40 Fuel Injection Valve 50 Cylinder

Claims (12)

A fuel injection connecting device connected to a fuel injection valve for injecting fuel into a cylinder of an internal combustion engine,
A main fuel passage through which main fuel flows, a sub fuel passage through which sub fuel flows, a main body having a confluence passage through which the main fuel and the sub fuel are joined, and a main fuel pipe that supplies the main fuel A main fuel system connection portion provided at an end of the main fuel flow path of the main body to be connected, and a sub fuel pipe for supplying the sub fuel via a sub fuel injection valve for injecting the sub fuel. A sub fuel system connection provided at an end of the sub fuel flow path of the main body, and a fuel injection valve system connection provided at an end of the merge flow path of the main body connected to the fuel injection valve. Prepared,
The fuel injection valve system connection portion is formed to be equal in connection structure with the main fuel system connection portion, and the sub fuel system connection portion is different from the fuel injection valve system connection portion and the main fuel system connection portion in connection structure. A fuel injection connecting device capable of dealing with various types of fuels.   2. The fuel injection connecting device according to claim 1, wherein the main fuel flow path is provided with a main fuel flow path check valve for preventing a back flow of the fuel.   The fuel injection connecting device according to claim 1 or 2, further comprising a sub fuel injection valve for injecting the sub fuel into the sub fuel flow path.   4. The fuel injection connecting device according to claim 3, wherein the connecting portion of the auxiliary fuel injection valve also serves as the auxiliary fuel system connecting portion.   5. The sub fuel injection valve is connected to the main fuel flow path at an angle of less than 90 degrees with respect to the flow direction of the main fuel and the sub fuel. A fuel injection connecting device capable of handling the various fuels described in 1.   The auxiliary fuel flow path is formed in the main body in parallel with the main fuel flow path, and the junction with the main fuel flow path is located in the vicinity of the fuel injection valve system connection portion, and the length of the merge flow path. 6. The fuel injection unit capable of handling multiple fuels according to claim 1, wherein the length is shorter than a length of the main fuel flow path or the sub fuel flow path. Connected device.   The valve body of the main fuel check valve faces the downstream side of the main fuel flow path, and the biasing means for biasing the valve body faces the upstream side of the valve body. A connecting device for fuel injection capable of handling various fuels according to any one of claims 2 to 6.   The fuel capable of handling various fuels according to any one of claims 1 to 7, further comprising: a sub fuel flow path check valve for preventing a back flow of the fuel in the sub fuel flow path. Connecting device for injection. A fuel injection system using a fuel injection connecting device capable of handling various fuels according to one of claims 1 to 8,
A fuel injection system using a fuel injection connecting device capable of dealing with various fuels, comprising a high-pressure pump for supplying the auxiliary fuel at a high pressure, and a common rail for storing the high-pressure auxiliary fuel.   A system check valve for preventing back flow of the fuel when the pressure of the sub fuel becomes lower than the pressure of the main fuel is provided in the sub fuel pipe between the common rail and the sub fuel system connection portion. The fuel-injection system using the connecting apparatus for fuel-injection corresponding to the various fuel of Claim 9 characterized by these. A connection method using a fuel injection connecting device capable of handling multiple fuels according to one of claims 1 to 8,
Removing the main fuel pipe connected to the fuel injection valve for supplying the main fuel into the cylinder of the internal combustion engine; and connecting the fuel injection valve system connection portion of the fuel injection connecting device to the fuel injection Step 2 for attaching to the valve, Step 3 for connecting the removed main fuel pipe to the main fuel system connection portion of the fuel injection connection device, and the sub fuel system connection portion of the fuel injection connection device to the sub fuel system connection portion. A connection method using a fuel injection connecting device capable of dealing with various fuels, comprising: connecting a fuel pipe to step 4;   12. The connection method using the fuel injection connecting device according to claim 11, further comprising a step 5 of connecting a common rail to the auxiliary fuel pipe.