JP2008248839A - Cam driven fuel injection system for large size two cycle diesel engine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an energy saving engine provided with flexible fuel injection system having high redundancy. <P>SOLUTION: A large size two cycle diesel engine provided with an exhaust valve operation system is provided with a camshaft and a hydraulic push rod, and is provided with a piston pump 32 driven by the cam shaft 28 connected to a hydraulic exhaust valve actuator 34 moving the exhaust valve 11 via a conduit 36. The camshaft is provided with a fuel cam 30 for each cylinder, and the fuel cam acts on a same positive displacement pump as an exhaust cam 29 for the cylinder. Hydraulic driven fuel pump 43 associates with each cylinder, and the fuel pump is connected to at least one fuel injection device associated with the cylinder for supplying high pressure fuel to the fuel injection device. The fuel pump is hydraulically driven by a single positive displacement pump associated with the cylinder. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a cam-driven exhaust valve and a fuel injection system for an internal combustion engine, and more particularly to a cam-driven hydraulic exhaust valve operation and a fuel injection system for a large two-cycle diesel engine.

  A crosshead type large two-cycle diesel engine is used as, for example, a propulsion engine of a large ocean-going ship or a main prime mover of a power plant. These two-cycle diesel engines are not only in size, but different in configuration from other internal combustion engines. It is a unique class in the engine field due to the two-cycle principle and the use of heavy oil with a viscosity of 700 cSt or less at 50 ° C. (oil does not flow at room temperature).

  The demand for improved performance and reduced exhaust gas has led to the development of common rail electrohydraulic controlled exhaust valve actuation systems and electronically controlled fuel injection systems for these two-cycle diesel engines. The advantage of these systems is that the timing for opening and closing the exhaust valve and the fuel profile can be freely selected according to the operating conditions of the engine. However, these common rail electro-hydraulic systems are relatively expensive, consume more energy than necessary during the opening process of the exhaust valve, and are not compensated for during the closing process. It consumes more energy than the system. Hydraulic power is provided by an electrically driven starter pump and a set of high pressure pumps with a constant outlet pressure realized by stepless adjustment of capacity. The pump is driven by a single mechanical gear connected to the crankshaft. A hydraulically driven fuel injection pump is connected to a high pressure system having a long pipe and a plurality of extended pipe connections. This system has low redundancy because the engine may become inoperable due to damage to gears, failure of stepless capacity adjustment, or damage to pipes and pipe connections caused by natural pressure oscillations. These two drawbacks negate the many advantages of electronically controlled engines.

  In view of such a background, it is an object of the present invention to provide an energy saving engine of the type described above that includes a flexible fuel injection system with high redundancy.

  The object is a crosshead type large two-cycle diesel engine, each cylinder comprising at least one exhaust valve and at least one fuel injection device, and at least the cylinders associated with each of the plurality of cylinders At least one camshaft having a plurality of exhaust cams for operating each of the exhaust valves, and a hydraulic pushrod corresponding to the range of the cylinder, wherein the hydraulic pushrod is on the camshaft A hydraulic piston pump driven by a corresponding cam is provided for each actuator, a hydraulic actuator for moving the corresponding exhaust valve in the opening direction, and a hydraulic oil pipe for connecting the hydraulic piston pump to the corresponding hydraulic actuator For each exhaust valve, the camshaft, Each cylinder is provided with a fuel cam, wherein the fuel cam acts on the same positive displacement pump as the exhaust cam of the corresponding cylinder, and the camshaft further comprises a hydraulically driven fuel pump associated with each cylinder. Wherein the fuel pump is connected to the injector to supply high pressure fuel to the at least one fuel injector associated with the corresponding cylinder, and the positive displacement type associated with the corresponding cylinder. This is achieved by providing a crosshead type large two-cycle diesel engine characterized in that it is hydraulically driven by a pump.

  Thus, the hydraulic push rod positive displacement pump is converted to a multipurpose hydraulic power supply. One positive displacement pump per cylinder can be eliminated by operably connecting the fuel pump to a positive displacement pump that normally only supplies hydraulic oil to the exhaust valve. Accordingly, the complexity of the operation of the exhaust valve and the fuel injection system is reduced, and the exhaust valve can be made inexpensive while maintaining high redundancy.

  The fuel pump is preferably operatively connected to the positive displacement pump via a selection valve that selectively connects the exhaust valve actuator and the fuel pump to the positive displacement pump of the corresponding cylinder. Accordingly, the hydraulic power generated for the exhaust valve actuator can be directed to the exhaust valve actuator, and the hydraulic power generated for the fuel pump can be guided to the fuel pump by changing the position of the selection valve. it can.

  The fuel cam and exhaust cam can be located on the same track on the camshaft, thereby acting on the same roller connected to the corresponding positive displacement pump.

  The fuel pump preferably has a displacement control system for adjusting the amount of fuel injected for engine operating conditions. The fuel pump can also include a variable injection timing system.

  Alternatively, the connection between the positive displacement pump and the fuel pump may include a control valve configured to control the amount of fuel supplied by the fuel pump to the at least one fuel injector.

  The connection between the positive displacement pump and the fuel pump can include an accumulator. Thus, excess energy supplied by the positive displacement pump can be stored and then returned to the camshaft to reduce the energy consumed by the exhaust valve actuator and the fuel injection system.

  The selection valve can be controlled electronically. Alternatively, the selection valve is mechanically controlled by a cam on the camshaft or on another camshaft.

  The connection between the positive displacement pump and the fuel pump includes an accumulator, an electronic control valve for controlling the amount of fuel supplied by the fuel pump to the at least one fuel injector, and the fuel supplied by the fuel pump. And an overflow valve upstream of the electronic control valve for controlling the amount. The accumulator is filled by the pump stroke of the positive displacement pump. Part of the accumulator capacity is used for fuel injection, while the rest is returned to the positive displacement pump on the return stroke.

  The engine may further comprise an electronically controlled release valve for releasing hydraulic oil in a tank between the selection valve and a valve for controlling the amount of fuel supplied by the fuel pump. When the pressure in the system reaches a level corresponding to full charge of the accumulator, the electronically controlled release valve is opened into the tank, allowing further hydraulic fluid supplied by the positive displacement pump to flow into the tank. This is reduced as the resistance experienced by the camshaft, saving energy.

  Alternatively, the engine can include a pressure relief valve that has an opening pressure that corresponds to the pressure in the accumulator that corresponds to maximum fuel injection. Thus, any excess hydraulic fluid supplied by the positive displacement pump is directed to the tank.

  The engine may further comprise a device connected to each of the hydraulic push rods in order to controllably add or remove hydraulic oil to the corresponding push rods. Thus, the hydraulic exhaust valve actuator can open earlier than defined by the cam shape and can remain open longer than defined by the cam shape.

  The apparatus can comprise a controllable pressurized hydraulic fluid source connected to each of the hydraulic push rods and a controllable hydraulic fluid outlet connected to each of the hydraulic fluid tubes.

  The apparatus can be configured to add a predetermined amount of hydraulic fluid to the conduit before or during the operational phase of the cam associated with the corresponding cylinder. Therefore, the opening / closing timing of the exhaust valve can be flexibly adapted to the actual operating conditions of the engine.

  The apparatus can be configured to drain a predetermined amount of hydraulic fluid to the hydraulic push rod during or after the actuation phase of the cam associated with the corresponding cylinder.

  A capacity limiter may be further provided between the electronically controlled hydraulic valve and the hydraulic push rod.

  Further objects, functions, advantages, and characteristics of the large two-cycle diesel engine according to the present invention will become apparent from the following detailed description.

Detailed Description of the Preferred Embodiment

  In the following detailed part of the description, the invention will be described in more detail with reference to exemplary embodiments shown in the drawings.

  1 and 2 show a cross-sectional view and a longitudinal cross-sectional view, respectively, of an engine 1 according to a preferred embodiment of the invention. The engine 1 is a crosshead type single-flow low-speed two-cycle crosshead diesel engine, and can be a marine vessel propulsion system or a main prime mover of a power plant. These engines typically have 4 to 14 cylinders in series. The engine 1 is assembled from a base plate 2 having a main bearing for the crankshaft 3.

  The crankshaft 3 is a semi-assembled type. The semi-assembled mold is formed of forged steel or cast steel throw that is connected to the main journal by shrink-fit connection.

  The base plate 2 can be formed of a single part or divided into suitably sized parts according to production equipment. The base plate is composed of a side wall and a welded cross beam including a bearing support. The cross beam is also referred to as “crossing beam” in the prior art. The oil receiver 58 is welded to the bottom of the base plate 2 and collects return oil from the forced lubrication and cooling oil system.

  The connecting rod 8 connects the crankshaft 3 to the crosshead bearing 22. The crosshead bearing 22 is guided between the vertical guide surface 23.

  A welded design A-shaped frame box 4 is mounted on a base plate 2. The frame box 4 is a welding design. The exhaust side of the frame box 4 is provided with a relief valve for each cylinder, and the camshaft side of the frame box 4 is provided with a large hinged door for each cylinder. The crosshead guide surface 23 is integrated into the frame box 4.

  The cylinder frame 5 is placed on top of the frame box 4. The retaining bolt 27 connects the base plate 2, the frame box 4, and the cylinder frame 5, and uniformly maintains the structure. The reserve bolt 27 is tightened with a hydraulic jack.

  The cylinder frame 5 is cast into one or more parts and is ultimately cast with an integral camshaft housing 25 or is a welded design. According to another embodiment (not shown), the camshaft 28 is housed in a separate camshaft housing attached to the cylinder frame.

  The cylinder frame 5 includes an access cover for purifying the scavenging space and inspecting the scavenging port and the piston ring from the cam shaft side. The cylinder frame 5 forms a scavenging space together with the cylinder liner 6. The scavenging receiver 9 is fixed to the cylinder frame 5 with bolts together with the opening side. There is a piston rod stuffing box at the bottom of the cylinder frame, which is equipped with a seal ring for scavenging and an oil scraper ring to prevent exhaust from entering the space of the frame box 4 and the base plate 2. Protect all bearings present in this space.

  The piston 13 includes a piston crown and a piston skirt. The piston crown is made of heat resistant steel and has four annular grooves with hard chrome plated on both the upper and lower surfaces of the groove.

  The piston rod 14 is connected to the crosshead 22 with four screws. The piston rod 14 has two coaxial holes (not shown in the figure) that form a cooling oil inlet / outlet for the piston 13 in conjunction with the cooling oil pipe.

  The cylinder liner 6 is carried by the cylinder frame 5. The cylinder liner 6 is made of alloy cast iron and is suspended in the cylinder frame 5 by a lower flange. The top of the liner is surrounded by a cooling jacket made of cast iron. The cylinder liner 6 has a drill hole (not shown) for cylinder lubrication.

  The cylinder is a single flow type and has a scavenging port 7 located in the air box. The air box is supplied with scavenging air pressurized by the turbocharger 10 (FIG. 1) from the scavenging receiver 9 (FIG. 1). The

  The engine is fitted with one or more turbochargers 10 arranged on the rear end of the engine for 4 to 9 cylinders and on the exhaust side for engines of 10 or more cylinders.

  Intake into the turbocharger 10 is performed directly from the engine room via the intake silencer of the turbocharger. Air is guided from the turbocharger 10 to a scavenging port 7 of the cylinder liner 6 through an air supply pipe (not shown), an air cooler (not shown), and a scavenging receiver 9.

  The engine includes an electric scavenging blower (not shown). The suction side of the blower is connected to the scavenging space behind the air cooler. A check valve (not shown) is installed between the air cooler and the scavenge receiver that automatically closes when the auxiliary blower supplies air. The auxiliary blower assists the turbocharger compressor at low and medium load conditions.

  The fuel valve 40 is placed concentrically within the cylinder cover 12. At the end of the compression stroke, the injection valve 40 injects fine mist fuel at high pressure into the combustion chamber 15 via these injection nozzles. The exhaust valve 11 is placed at the upper center of the cylinder in the cylinder cover 12. At the end of the expansion stroke, the exhaust valve 11 opens before the piston 13 of the engine descends past the scavenging port 7, so that the combustion gas in the combustion chamber 15 above the piston 13 opens to the exhaust receiver 17. It flows out through the flow path 16, and the pressure in the combustion chamber 15 is reduced. The exhaust valve 11 is closed again while the piston 13 moves upward. The exhaust valve 11 is hydraulically operated.

  FIG. 3 shows a first embodiment of an exhaust valve actuation system according to the present invention. The exhaust valve actuation system is for all of the embodiments shown for a single cylinder. In a multi-cylinder engine, the same conditions are applied to each cylinder. An exhaust valve actuation system for a non-reversible engine includes a camshaft 28 that includes an exhaust cam 29 and a fuel cam 30 (only one cylinder is shown because only one cylinder is shown). . The roller 31 is connected to the piston of the positive displacement pump 32 according to the surface of the cams 29, 30. The positive displacement pump 32 is connected to the exhaust valve actuator 34 and the fuel pump 43 via a selection valve 33 that selectively connects the conduit 36 and the positive displacement pump 32 to the exhaust valve actuator 34 and the fuel pump 43. The selector valve 33 connects the conduit 36 to the exhaust valve actuator 34 in one of its two positions, and in the other of its two positions, the selector valve connects the conduit 36 to the fuel pump actuator 45 of the fuel pump 43. Connect via conduit 41. The position of the selection valve 33 is determined by the cam 35 on the cam shaft 28. Alternatively, cam 35 can be located on a separate cam shaft (not shown) that rotates in the same direction and speed as cam 28. Therefore, the selection valve 33 connects the positive displacement pump 32 to the fuel pump 43 when the fuel cam 30 is operating at the position shown in FIG. Since the selection valve 33 is in a different position when the exhaust cam 29 is in operation, hydraulic oil flows from the positive displacement pump 32 to the exhaust valve actuator 34.

  The stroke as caused by the fuel pump 43 and the fuel pump actuator 45 is determined by the amount of hydraulic oil supplied by the fuel cam 30 during its operating period. In this way, the stroke of the fuel pump 43 is determined. In order to control the amount of fuel injected into the cylinder, the fuel pump 34 includes a regulator 48 for controlling the amount of fuel injected in each stroke of the fuel pump 43, and a variable for controlling the injection timing. And an injection timing system 51. The regulator 48 and the variable injection timing system 51 are connected to an engine electronic control system (ECU) (not shown in FIG. 3). When fuel injection is performed, the pressure is released without consuming further energy in the fuel pump 43. During the intake stroke of the positive displacement pump 32, only the amount of hydraulic oil corresponding to the leakage loss is replenished via the check valve 53.

  The exhaust valve actuator 34 acts on the shaft of the exhaust valve 11. The gas spring 38 is also connected to the shaft of the exhaust valve, and the gas pressure in the pressure chamber of the gas spring 38 moves the exhaust valve 11 in the closing direction. When the valve actuator 34 is pressurized, the gas pressure moves the exhaust valve in the opening direction. During operation, the camshaft 28 rotates in the direction of the arrow above the “TDC” indication indicating the top dead center of the piston in line with the crankshaft of the engine. The shape of the cams 29 and 30 determines the operation of the positive displacement pump 32. When the positive displacement pump 32 moves upward, hydraulic oil is pressed into the valve actuator 34 or the fuel pump actuator 45 according to the position of the selection valve 33. The actuator 34 opens the exhaust valve 11 against the pressure in the combustion chamber and the gas spring 38. When the positive displacement pump 32 moves downward, the gas spring 38 moves the exhaust valve and the exhaust valve actuator 34 upward, whereby the hydraulic oil in the exhaust valve actuator 34 flows back into the positive displacement pump 32. Most of the energy transmitted to the exhaust valve actuator 34 during the opening operation of the exhaust valve 11 is returned to the camshaft 28 by the pressure generated during the return stroke of the exhaust valve actuator 34. Therefore, only a small part of the hydraulic energy required to open the exhaust valve 11 is dissipated.

  FIG. 4 shows a second embodiment of the exhaust valve actuation and fuel injection system according to the present invention, which is essentially the same as the embodiment described with reference to FIG. 3 except for the following differences. The accumulator 47 is connected to the conduit 41. Further, the control valve 49 controls the flow to / from the fuel pump actuator 45. The position of the fuel pump actuator 45 is determined by a sensor and sent to an electronic control system “ECU” of the engine. The position of the control valve 49 is electronically controlled by the ECU. The change in the position of the selection 33 is the same as in the first embodiment described above. The complete pump stroke of the positive displacement pump 32 as produced by the fuel injection cam 30 is stored in the accumulator 47. A part of the capacity of the accumulator 47 is used for fuel injection. This operation is performed under the control of the ECU and the control valve 49. Thus, the ECU connects the fuel pump actuator 45 and the conduit 41 during the time period necessary to inject the desired amount of fuel. The remaining hydraulic energy in the accumulator 47 is returned to the positive displacement pump 32 during the return stroke. The accumulator 47 is therefore loosened until its stop, which corresponds to the pretension pressure of the system. In this way, during the outdoor stroke of the fuel cam 30, most of the excess energy supplied by the positive displacement pump 32 is returned to the camshaft 28, minimizing energy loss.

  FIG. 5 shows a third embodiment of the exhaust valve actuation and fuel injection system according to the present invention, but with the implementation described with reference to FIG. 4 except that the selection valve 33 is electronically controlled by the ECU. Essentially the same as the embodiment.

  FIG. 6 shows a fourth embodiment of an exhaust valve actuation and fuel injection system according to the present invention, which is essentially the same as the embodiment described with reference to FIG. 3, except for the following differences. In this embodiment, the selection valve 33 is removed, and its function is replaced with a check valve 52 in combination with the pressure relief valve 50. The check valve 52 is preferably 1 bar or less as a relatively low opening pressure. The opening pressure of the pressure relief valve 50 corresponds to the pressure in the accumulator 47 when the full capacity is filled. In this embodiment, the pretension pressure in the accumulator 47 must be higher than the maximum hydraulic pressure in the opening of the exhaust valve 11, and the opening pressure of the relief valve 50 is increased during the compression stroke of the engine. The hydraulic pressure that can be opened must be less than. The exhaust valve 11 operates in a conventional manner without flowing hydraulic oil to the fuel injection system. During the compression stroke of the engine, the accumulator 47 is filled to full capacity. With a further increase in pressure, the pressure relief valve 50 opens and excess capacity of the positive displacement pump 32 is led to the tank.

  FIG. 7 shows a fifth embodiment of an exhaust valve actuation and fuel injection system according to the invention for a non-reversible engine, but essentially the embodiment described with reference to FIG. 6 with the following differences. Are the same. In the present embodiment, the fuel cam 30 is disposed on the exhaust cam 29. Further lift by the fuel cam 30 after the exhaust valve 11 is opened provides further stroke to the positive displacement pump 32 that initially moved the exhaust valve 11 to a lower position. This further stroke causes the hydraulic oil to open the check valve 52 and fill the accumulator 47 to its maximum level. Any excess hydraulic fluid is directed to the tank by pressure relief valve 50. Thereafter, the exhaust valve 11 closes in the conventional manner and refills the positive displacement pump 32 in the subsequent suction stroke. In this embodiment, the pressure in the accumulator during full filling can be higher than the pressure at which the exhaust valve 11 is opened during the compression stroke of the engine. FIG. 7 corresponds to the bottom dead center “BDC” of the piston in the cylinder 6.

  FIG. 8 shows a sixth embodiment of an exhaust valve actuation and fuel injection system according to the present invention, which is essentially the same as the embodiment described with reference to FIG. 5, except for the following differences. In this embodiment, a further control valve 54 is arranged between the selection valve 33 and the accumulator 47. The further control valve 54 is controlled by the ECU, and a pressure sensor 59 that measures the pressure in the conduit 41 (equal to the pressure in the accumulator 47) is also connected to the ECU. When the accumulator 47 is completely filled (detected via the pressure sensor 59), the ECU passes the additional control valve 54 to direct additional hydraulic fluid from the positive displacement pump 32 to the tank without consuming energy. Send a signal.

  FIG. 9 shows a sixth embodiment of the exhaust valve actuation and fuel injection system according to the present invention, which is essentially the same as the embodiment described with reference to FIG. 5 except for the following differences. The exhaust valve system comprises in this embodiment a 3/2 valve 46 having one port connected to the exhaust valve actuator 34 via a capacity limiter 44. The inlet of the 3/2 valve 46 is connected to the pressurized hydraulic oil source 61, and the outlet of the 3/2 valve 46 is connected to the drain or tank.

  The 3/2 valve 46 is electronically controlled by the ECU. During operation, the 3/2 valve 46 can add and remove hydraulic fluid to the exhaust valve actuator 34 at a desired time during the operating cycle.

  Graph 42 illustrates the potential for the addition and / or removal of hydraulic fluid from the exhaust valve actuator 34. The upper curve of the graph 42 represents the position of the exhaust valve 11 when a certain amount of hydraulic oil is added to the exhaust valve actuator 34. The exhaust valve 11 can be opened earlier than defined by the shape of the cam 29 by adding an additional amount of hydraulic fluid to the exhaust valve actuator 34 with a 3/2 valve 46 before the cam 29 begins to operate. .

  Additional amounts of hydraulic fluid can be withdrawn before or after closing the exhaust valve as defined by the cam 29 by changing the position of the 3/2 valve 46. The volume limiter 44 prevents too much from being added to or removed from the exhaust valve actuator 34.

  When a further amount of hydraulic oil is removed before the closing time of the exhaust valve 11 defined by the shape of the cam 29, the exhaust valve closes as defined by the cam 29. If an additional amount of hydraulic oil is removed after the closing time of the exhaust valve 11 defined by the shape of the cam 29, the exhaust valve will remain open for a longer time. The exhaust valve actuation system according to this embodiment provides the possibility of profiling, that is, changing the timing of opening the exhaust valve 11 and changing the timing of closing the exhaust valve 11. By controlling the 3/2 stage-valve 46, the exhaust valve actuation system according to this embodiment can change between the upper and lower curves of the graph 42 at a desired point in the engine cycle. .

  The blowback and compression pressure from the cylinder can be adjusted by changing the timing for opening and closing the exhaust valve 11. Algorithms and data for optimal timing / profiling for opening and closing the exhaust valve 11 are stored in the electronic control system ECU and applied based on operating conditions and engine characteristics.

  FIG. 10 shows a seventh embodiment of an exhaust valve actuation and fuel injection system according to the present invention, but with the same system for adding and removing hydraulic fluid to the exhaust valve actuator 34 described with reference to FIG. It is essentially the same as the embodiment described with reference to FIG.

  The term “comprising”, used in the claims, does not exclude other elements. Of the terms used in the claims, those not described as “plurality” do not exclude a plurality.

  Although the present invention has been described in detail for purposes of illustration, it is to be understood that such details are merely for that purpose and that one skilled in the art can make changes without departing from the scope of the invention.

1 is a cross-sectional view of an engine according to the present invention. FIG. 2 is a longitudinal sectional view of one cylinder section of the engine shown in FIG. 1. 1 is a symbolic view of a first embodiment of an exhaust valve actuation and fuel injection system according to the present invention. FIG. FIG. 3 is a symbolic view of a second embodiment of the exhaust valve actuation and fuel injection system according to the present invention. FIG. 7 is a symbolic view of a third embodiment of the exhaust valve actuation and fuel injection system according to the present invention. FIG. 7 is a symbolic view of a fourth embodiment of an exhaust valve actuation and fuel injection system according to the present invention. FIG. 7 is a symbolic view of a fifth embodiment of the exhaust valve actuation and fuel injection system according to the present invention. FIG. 7 is a symbolic view of a sixth embodiment of the exhaust valve actuation and fuel injection system according to the present invention. FIG. 9 is a symbolic illustration of a seventh embodiment of an exhaust valve actuation and fuel injection system according to the present invention. FIG. 10 is a symbolic view of an eighth embodiment of the exhaust valve actuation and fuel injection system according to the present invention.

Claims (16)

A crosshead large two-cycle diesel engine,
A plurality of cylinders, each cylinder comprising at least one exhaust valve and at least one fuel injector;
At least one camshaft comprising a plurality of exhaust cams for respectively operating the at least one exhaust valve associated with each of the plurality of cylinders;
A hydraulic push rod corresponding to the range of the cylinder, wherein the hydraulic push rod includes a hydraulic piston pump driven by a corresponding cam on the cam shaft for each actuator, and the corresponding exhaust valve. A hydraulic actuator for moving in the opening direction and a hydraulic oil pipe for connecting the hydraulic piston pump to the corresponding hydraulic actuator for each exhaust valve;
The camshaft is provided with a fuel cam in each cylinder, where the fuel cam acts on the same positive displacement pump as the exhaust cam of the corresponding cylinder;
The camshaft further comprises a hydraulically driven fuel pump associated with each cylinder, wherein the fuel pump is adapted to supply high pressure fuel to the at least one fuel injector associated with the corresponding cylinder. A cross-head type large two-cycle diesel engine connected to a device and hydraulically driven by the positive displacement pump associated with the corresponding cylinder.   The engine of claim 1, wherein the fuel pump is operatively connected to the positive displacement pump associated with the corresponding cylinder.   The fuel pump is operably connected to the positive displacement pump via a selection valve that selectively connects the exhaust valve actuator and the fuel pump to a corresponding positive displacement pump of the cylinder. The listed engine.   The engine according to claim 1, wherein the fuel cam and the exhaust cam are disposed on the same track on the camshaft.   The engine of claim 1, wherein the fuel pump has a displacement control system.   The connection between the positive displacement pump and the fuel pump includes a control valve configured to control the amount of fuel supplied by the fuel pump to the at least one fuel injector. The listed engine.   The engine of claim 6, wherein the connection between the positive displacement pump and the fuel pump includes an accumulator.   The engine according to claim 3, wherein the valve that selectively connects the exhaust valve actuator and the fuel pump is electronically controlled.   The engine according to claim 3, wherein the selection valve is mechanically controlled by a cam on the camshaft or on another camshaft.   The connection between the positive displacement pump and the fuel pump is achieved by an accumulator, an electronic control valve for controlling the amount of fuel supplied by the fuel pump to the at least one fuel injector, and the fuel pump. An engine according to claim 1, including an overflow valve upstream of the electronic control valve for controlling the amount of fuel supplied.   The engine of claim 10, further comprising an electronic control valve for releasing hydraulic oil in a tank between the selection valve and the valve for controlling the amount of fuel supplied by the fuel pump.   The engine of claim 1, further comprising a device connected to each of the corresponding hydraulic push rods for controllably adding or removing hydraulic oil to the hydraulic push rods.   13. The device of claim 12, comprising a controllable pressurized hydraulic fluid source connected to each of the hydraulic push rods and a controllable hydraulic fluid outlet connected to each of the hydraulic push rods. Engine.   3. The device according to claim 1 or 2, wherein the device is configured to add a predetermined amount of hydraulic oil to the hydraulic push rod before or during the operation phase of the cam associated with the corresponding cylinder. engine.   The engine of claim 14, wherein the device is configured to withdraw a predetermined amount of hydraulic fluid from the hydraulic push rod during or after the actuation phase of the cam associated with the corresponding cylinder.   The engine of claim 15, further comprising a capacity limiter between the electronically controlled hydraulic valve and the hydraulic push rod.

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