KR102279170B1 - Variable Compression Units and Engine Systems - Google Patents

Abstract

The variable compression device A includes a piston rod 6 having a flange 6c formed at the end thereof, a fluid chamber R3 in which the piston rod is moved in a direction to increase the compression ratio by supplying a pressurized working fluid, and a flange. a regulating member (7c) provided on the opposite side to the fluid chamber and regulating movement in a direction to increase the compression ratio of the piston rod, and a regulating member-side fluid chamber formed between the flange and the regulating member with the flange as the bottom surface ( R7), a supply flow path R6 for supplying a cooling fluid to the regulating member-side fluid chamber, and a piston rod having an open end on the bottom surface and guiding the cooling fluid in the regulating-member-side fluid chamber to the inside of the piston rod It has an internal flow path R8.

Description

Variable Compression Units and Engine Systems

The present disclosure relates to a variable compression device and an engine system.

This application claims priority based on Japanese Patent Application No. 2017-228333 for which it applied on November 28, 2017, and uses the content here.

For example, Patent Document 1 discloses a large reciprocating piston combustion engine having a crosshead. The large reciprocating piston combustion engine of Patent Document 1 is a dual fuel engine that can be operated with both liquid fuel such as heavy oil and gaseous fuel such as natural gas. The large reciprocating piston combustion engine of Patent Document 1 includes an adjustment mechanism for changing the compression ratio by moving the piston rod by hydraulic pressure in order to correspond to both a compression ratio suitable for operation by liquid fuel and a compression ratio suitable for operation by gaseous fuel It is provided in the cross head part.

Patent Document 1: Japanese Patent Application Laid-Open No. 2014-20375

In the engine system which has the compression adjustment device which changes a compression ratio as mentioned above, a part of the working fluid supplied to an adjustment mechanism (hydraulic chamber) may be supplied to the inside of a piston as a cooling fluid via a piston rod. In order to supply the cooling fluid to the inside of the piston via the piston rod, it is possible to use a working fluid leaking from the hydraulic chamber side, or to supply the cooling fluid from an opening formed on the side of the piston rod. However, in the case of using the working fluid leaking from the fluid chamber (hydraulic chamber) side, it may be difficult to stably supply the working fluid. In addition, when supplying the cooling fluid from the opening formed on the side of the piston rod to the inside of the piston rod, since the relative position of the piston rod and the fluid chamber differs depending on the compression ratio, it is necessary to provide a large opening in the piston rod. , there is a possibility that the movable area of the piston rod is limited.

The present disclosure has been made in view of the above-described problems, and an object of the present disclosure is to be able to stably supply a cooling fluid to the inside of the piston and to expand the movable area of the piston rod.

In order to solve the above problems, the variable compression device of the first aspect of the present disclosure includes: a piston rod having a flange formed at an end thereof; a fluid chamber in which the piston rod is moved in a direction to increase a compression ratio by supplying a pressurized working fluid; a regulating member provided on the opposite side to the fluid chamber with a flange interposed therebetween to regulate movement in a direction to increase the compression ratio of the piston rod; and a regulating member formed between the flange and the regulating member with the flange as a bottom surface A piston having a side fluid chamber, a supply passage for supplying a cooling fluid to the regulating member-side fluid chamber, and an open end on the bottom surface, and guiding the cooling fluid in the regulating member-side fluid chamber to the inside of the piston rod. The rod has an internal flow path.

In a second aspect of the present disclosure, in the first aspect, an open end of the supply flow path is formed on a surface of the regulating member opposite to the regulating member-side fluid chamber.

In a third aspect of the present disclosure, the variable compression device according to the first aspect further includes a fluid chamber forming member constituting the regulating member-side fluid chamber by inserting the end portion of the piston rod, and a notch is formed on the bottom surface. is formed, an open end of the supply flow passage is formed on a surface of the fluid chamber forming member opposite to the regulating member side fluid chamber, and an open end of the piston rod internal flow passage is formed in the notch.

A fourth aspect of the present disclosure is any one of the first to third aspects, wherein the flange has a groove passage in a region overlapping with an open end of the piston rod inner passage.

An engine system according to a fifth aspect of the present disclosure includes the variable compression device according to any one of the first to fourth aspects.

According to the present disclosure, the cooling fluid is guided from the flow path opening formed in the flange of the piston rod corresponding to the bottom surface of the regulating member side fluid chamber to the piston rod internal flow path. Thereby, when supplying a cooling fluid to a piston, it is not necessary to form the radial direction flow path connected with the piston rod internal flow path from the side of a flange. Therefore, since there is no restriction on the thickness of the flange of the piston rod, it is possible to sufficiently secure the amount of movement of the flange in the fluid chamber, that is, the amount of movement of the piston rod by the variable compression device while supplying the cooling fluid stably.

BRIEF DESCRIPTION OF THE DRAWINGS It is sectional drawing of the engine system in one Embodiment of this indication.
2 : is a schematic sectional drawing which shows a part of the engine system in one Embodiment of this indication.
It is a schematic sectional drawing which shows the flow of the hydraulic oil of the engine system in one Embodiment of this indication.
It is a schematic sectional drawing which shows the flow of hydraulic oil in the modification of the engine system in one Embodiment of this indication.

EMBODIMENT OF THE INVENTION Hereinafter, one Embodiment of the two-stroke engine in this indication is described with reference to drawings.

[First embodiment]

The engine system 100 of this embodiment is mounted on ships, such as a large tanker, for example, and as shown in FIG. 1, it has the engine 1, the supercharger 200, and the control part 300. In addition, in this embodiment, the supercharger 200 is grasped|ascertained as an auxiliary|assistance, and it demonstrates as a body separate from the engine 1 (main). However, it is also possible to configure the supercharger 200 as a part of the engine 1 . In addition, the supercharger 200 is not an essential component for the engine system 100 of this embodiment, and does not need to be provided in the engine system 100 .

1 is a longitudinal cross-sectional view taken along the central axis of a cylindrical cylinder liner 3a, which will be described later, installed in the engine system 100. As shown in FIG. In FIG. 1, the side to which the exhaust valve unit 5 mentioned later is provided is called upper side, and the side to which the crankshaft 11 mentioned later is provided may be called a lower side. A direction intersecting the central axis of the cylinder liner 3a is sometimes referred to as a radial direction. The view seen from the central axis direction of the cylinder liner 3a is sometimes called a planar view.

The engine 1 becomes a multi-cylinder uniflow scavenging diesel engine, and has a gas operation mode in which gaseous fuel such as natural gas is combusted together with liquid fuel such as heavy oil, and a diesel operation mode in which liquid fuel such as heavy oil is burned. It is a viable dual fuel engine. In addition, in the gas operation mode, you may burn only gaseous fuel. The engine 1 includes a furniture 2 , a cylinder part 3 , a piston 4 , an exhaust valve unit 5 , a piston rod 6 , a crosshead 7 , and , the hydraulic unit 8 (pressure boosting mechanism), the connecting rod 9 , the crank angle sensor 10 , the crankshaft 11 , the scavenging air tank unit 12 , the exhaust tank unit 13 , the air It has a cooler 14 . Moreover, the cylinder is comprised by the cylinder part 3, the piston 4, the exhaust valve unit 5, and the piston rod 6. As shown in FIG.

The furniture 2 is a strength member for supporting the entire engine 1 , and the crosshead 7 , the hydraulic unit 8 , and the connecting rod 9 are accommodated therein. Moreover, in the furniture 2, the crosshead pin 7a mentioned later of the crosshead 7 is reciprocally movable inside.

The cylinder part 3 has a cylindrical cylinder liner 3a, a cylinder head 3b, and a cylinder jacket 3c. The cylinder liner 3a is a cylindrical member, and the sliding surface with the piston 4 is formed inside (inner peripheral surface). A space surrounded by the inner circumferential surface of the cylinder liner 3a and the piston 4 constitutes the combustion chamber R1. Further, a plurality of scavenging ports S are formed under the cylinder liner 3a. The scavenging port S is an opening arranged along the circumferential surface of the cylinder liner 3a, and communicates with the scavenging air chamber R2 inside the cylinder jacket 3c and the inside of the cylinder liner 3a. The cylinder head 3b is a cover member provided on the upper end of the cylinder liner 3a. The cylinder head 3b has an exhaust port H formed in the central portion of the cylinder head 3b in plan view, and is connected to the exhaust tank portion 13 . In addition, a fuel injection valve (not shown) is provided in the cylinder head 3b. In the vicinity of the fuel injection valve of the cylinder head 3b, a cylinder pressure sensor (not shown) is provided. The cylinder pressure sensor detects the pressure in the combustion chamber R1 and transmits it to the control unit 300 . The cylinder jacket 3c is a cylindrical member provided between the furniture 2 and the cylinder liner 3a, and into which the lower end of the cylinder liner 3a is inserted, and the scavenging chamber R2 is formed therein. Further, the scavenging air chamber R2 of the cylinder jacket 3c is connected to the scavenging air tank portion 12 .

The piston 4 has a substantially cylindrical shape, is connected to a piston rod 6 described later, and is disposed inside the cylinder liner 3a. A piston ring (not shown) is provided on the outer peripheral surface of the piston 4, and the gap between the piston 4 and the cylinder liner 3a is sealed by the piston ring. The piston 4 slides in the vertical direction in the cylinder liner 3a along the piston rod 6 by the fluctuation of the pressure in the combustion chamber R1. Moreover, as for the piston 4, the inner side becomes hollow, and the ejection port 4a of the outer side flow path R8 mentioned later is formed in the inner lower surface side.

The exhaust valve unit 5 has an exhaust valve 5a, an exhaust valve casing 5b, and an exhaust valve driving unit 5c. The exhaust valve 5a is provided inside the cylinder head 3b and blocks the exhaust port H in the cylinder part 3 by the exhaust valve driving part 5c. The exhaust valve casing 5b is a cylindrical casing that accommodates the end of the exhaust valve 5a. The exhaust valve driving unit 5c is an actuator that moves the exhaust valve 5a in a direction along the stroke direction (sliding direction, up-down direction) of the piston 4 .

The piston rod 6 is an elongate member having one end (upper end) connected to the piston 4 and the other end (lower end) connected to the crosshead pin 7a. The end (lower end) of the piston rod 6 is inserted into the cross head pin 7a and connected so that the connecting rod 9 is rotatable. Moreover, the piston rod 6 has the flange 6c in which the diameter of a part of the edge part on the side of the crosshead pin 7a was formed large (refer FIG. 2). Further, as shown in Fig. 3 , the piston rod 6 has a double tube structure, and is composed of an outer tube 6a and an inner tube 6b accommodated in the outer tube 6a. The flange 6c is provided so as to protrude outward in the radial direction from the lower end portion (the portion inserted into the crosshead pin 7a) of the outer peripheral surface of the outer tube 6a. The inner tube 6b has a cylindrical body portion accommodated in the outer tube 6a and extending in the vertical direction, and a plate-shaped diameter enlarged portion extending radially outward from the upper end of the body portion inside the piston 4, have. A plurality of tubular protrusions with tops extending upward are provided in this diameter-enlarged portion, and a jet port 4a penetrating in the vertical direction is formed at the top of the protrusions. On the piston rod 6, from the upper surface of the flange 6c (the surface facing the cover member 7c described later) to the downward direction (the direction toward the lower surface of the flange 6c), the inner tube ( An outer flow passage R8 (piston rod inner passage) is formed that is bent toward 6b) and passes between the outer tube 6a and the inner tube 6b. In other words, the outer flow path R8 includes a first flow passage extending downward from the upper surface of the flange 6c, a second flow passage extending radially inward from the lower end of the first flow passage, and the second flow passage. a third flow path connected to the radial inner end of the outer tube 6a and the inner tube 6b and connected to the upper end of the third flow passage, and the diameter enlarged portion of the inner tube 6b; It has a 4th flow path provided between the bottom wall parts (lower wall parts) of the piston 4 . That is, in the flange 6c of the piston rod 6, the flow path opening (opening end) of the outer side flow path R8 is formed in the upper surface. Moreover, the inner pipe|tube 6b is provided with the inner side flow path R9 which communicates with the cavity inside the piston 4, and extends to the lower end of the piston rod 6 (end of the crosshead 7 side). In other words, the inner side of the main body portion of the inner tube 6b constitutes the inner flow path R9.

The crosshead 7 has a crosshead pin 7a (fluid chamber forming member), a guide shoe 7b, and a cover member 7c (regulating member). The crosshead pin 7a is a cylindrical member that movably connects the piston rod 6 and the connecting rod 9, and the end (lower end) and the flange 6c of the piston rod 6 are inserted, the piston rod A fluid chamber R3 (fluid chamber, a fluid chamber for changing a compression ratio) is formed between the flange 6c and the flange 6c of (6) to which supply and discharge of hydraulic oil (working fluid) are performed. The central axis of the crosshead pin 7a extends in a direction orthogonal to the vertical direction. An insertion recess is formed in the upper portion of the crosshead pin 7a, which is opened upward and into which the flange 6c is vertically slidably inserted. The above-described fluid chamber R3 is provided between the bottom surface of the insertion recess and the lower surface of the flange 6c. The crosshead pin 7a is provided with a discharge port O penetrating along the axial direction of the crosshead pin 7a below the center. The discharge port O is an opening through which the hydraulic oil (cooling fluid) that has passed through the inner flow path R9 of the piston rod 6 is discharged. Further, to the crosshead pin 7a, a supply flow path R4 connecting the fluid chamber R3 and a plunger pump 8c described later, and a relief connecting the fluid chamber R3 and a relief valve 8f described later are provided. A flow path R5 is provided.

The guide shoe 7b is a member that rotatably supports the crosshead pin 7a, and moves along a stroke direction of the piston 4 along a guide rail (not shown) along the crosshead pin 7a. When the guide shoe 7b moves along the guide rail, the movement of the crosshead pin 7a other than the linear direction along the stroke direction of the piston 4 is restricted. The rotational movement of the crosshead pin 7a around its central axis is also regulated. The cover member 7c is an annular member fixed to the upper part of the crosshead pin 7a and into which the end of the piston rod 6 is inserted. The lid member 7c is provided at the opening periphery of the insertion recess of the crosshead pin 7a. The inner diameter of the cover member 7c is equal to the outer diameter of the outer diameter 6a of the piston rod 6, and is smaller than the outer diameter of the flange 6c. In addition, a sealing ring (not shown) is provided on the cover member 7c on the sliding surface (radial inner surface) with the piston rod 6 . Thereby, the upper oil pressure chamber R7 (regulating member side fluid chamber) surrounded by the crosshead pin 7a, the cover member 7c, and the flange 6c of the piston rod 6 is formed. That is, the upper hydraulic chamber R7 is surrounded by the upper surface of the flange 6c, the inner surface of the insertion recess of the crosshead pin 7a, the lower surface of the cover member 7c, and the outer peripheral surface of the outer surface 6a. it is space Moreover, a part of the cooling oil supply flow path R6 (supply flow path) which guides the hydraulic oil supplied to the upper hydraulic chamber R7 is formed in the cover member 7c. The other part of the cooling oil supply flow path R6 is formed in the crosshead fin 7a. The cooling oil supply flow path R6 guides a part of the hydraulic oil pumped by a supply pump 8a to be described later from the crosshead pin 7a to the upper oil pressure chamber R7 via the cover member 7c. Euros. That is, the cooling oil supply flow path R6 is connected to the supply pump 8a. In each of the two cooling oil supply passages R6, a supply opening (opening end) is formed on a surface (lower surface) of the lid member 7c on the upper hydraulic chamber R7 side. In addition, this crosshead 7 transmits the linear motion of the piston 4 to the connecting rod 9 .

As shown in FIG. 2 , the hydraulic unit 8 includes a supply pump 8a, a swing tube 8b, a plunger pump 8c, and a first check valve connected to the plunger pump 8c ( It has 8d), the 2nd check valve 8e, and the relief valve 8f. In addition, the piston rod 6, the crosshead 7, the hydraulic part 8, and the control part 300 may function as the variable compression device A in this indication. This variable compression device A is configured such that the compression ratio of the engine 1 can be changed.

The supply pump 8a is a pump which pressurizes the hydraulic oil supplied from the hydraulic oil tank (not shown) based on the instruction|indication from the control part 300, and supplies it to the plunger pump 8c. The feed pump 8a is driven by the power of the ship's battery and it is possible to start before liquid fuel is supplied to the combustion chamber R1. The swing pipe 8b is a pipe connecting the supply pump 8a and the plunger pump 8c of each cylinder, and includes a plunger pump 8c moving along the crosshead pin 7a, and a fixed supply pump 8a. ) can be swung between

The plunger pump 8c is fixed to the crosshead pin 7a, and includes a rod-shaped plunger 8c1, a cylindrical cylinder 8c2 that slidably accommodates the plunger 8c1, and a plunger driving unit. (8c3). The plunger pump 8c slides in the cylinder 8c2 when the plunger 8c1 is connected to a drive unit (not shown), and pressurizes hydraulic oil to supply it to the fluid chamber R3. Moreover, in the cylinder 8c2, the 1st check valve 8d is provided in the opening on the discharge side of the hydraulic oil provided in the edge part, and the 2nd check valve 8e is provided in the opening on the suction side provided in the side circumferential surface. The plunger drive part 8c3 is connected to the plunger 8c1, and based on the instruction|indication from the control part 300, the plunger 8c1 reciprocates.

The first check valve 8d has a structure in which the valve body is biased toward the inside of the cylinder 8c2 by a bias member (not shown) to close, and the hydraulic oil supplied to the fluid chamber R3 flows back into the cylinder 8c2. preventing it from doing Moreover, when the pressure of the hydraulic oil in the cylinder 8c2 becomes more than the biasing force (opening pressure) of the biasing member of the 1st check valve 8d, the 1st check valve 8d will be opened when a valve body is pressed by the hydraulic oil. The second check valve 8e is biased toward the outside of the cylinder 8c2 by a bias member (not shown), and the hydraulic oil supplied to the cylinder 8c2 is prevented from flowing back to the supply pump 8a. Moreover, when the pressure of the hydraulic oil supplied from the supply pump 8a of the 2nd check valve 8e becomes more than the biasing force (opening pressure) of the biasing member of the 2nd check valve 8e, a valve body is pressed by the hydraulic oil. is open In addition, the opening pressure of the first check valve 8d is higher than the opening pressure of the second check valve 8e, and in normal operation operated at a preset compression ratio, the pressure of the hydraulic oil supplied from the supply pump 8a There is no opening by

The relief valve 8f is provided in the crosshead pin 7a, and has a body part 8f1 and a relief valve drive part 8f2. The body portion 8f1 is a valve connected to the fluid chamber R3 and a hydraulic oil tank (not shown). The relief valve drive part 8f2 is connected to the valve body of the main body part 8f1, and opens and closes the main body part 8f1 based on the instruction|indication from the control part 300. As shown in FIG. When the relief valve 8f is opened by the relief valve drive part 8f2, the hydraulic oil stored in the fluid chamber R3 is returned to the hydraulic oil tank.

As shown in FIG. 1 , the connecting rod 9 is an elongate member connected to the crosshead pin 7a and connected to the crankshaft 11 . The connecting rod 9 converts the linear motion of the piston 4 transmitted to the crosshead pin 7a into a rotational motion. The crank angle sensor 10 is a sensor for measuring the crank angle of the crankshaft 11 , and transmits a crank pulse signal for calculating the crank angle to the control unit 300 .

The crankshaft 11 is a long-shaped member connected to the connecting rod 9 provided in the cylinder, and is rotated by rotational motion transmitted by each connecting rod 9, thereby transmitting power to, for example, a screw or the like. . The scavenging air tank part 12 is provided between the cylinder jacket 3c and the supercharger 200, and the air pressurized by the supercharger 200 flows in. Moreover, the air cooler 14 is provided in the scavenging-air tank part 12 inside. The exhaust tank part 13 is a tubular member connected to the exhaust port H of each cylinder and connected to the supercharger 200 . The gas discharged from the exhaust port H is temporarily stored in the exhaust tank part 13 and is supplied to the supercharger 200 in a state in which pulsation is suppressed. The air cooler 14 is a device that cools the air inside the scavenging air tank unit 12 .

The supercharger 200 is a device that pressurizes air sucked in from an intake port (not shown) by a turbine rotated by the gas discharged from the exhaust port H, and supplies it to the combustion chamber R1.

The control unit 300 is a computer that controls, for example, an amount of fuel supplied based on an operation performed by the ship's pilot. Further, the control unit 300 changes the compression ratio in the combustion chamber R1 by controlling the hydraulic pressure unit 8 . Specifically, the control unit 300 controls the plunger pump 8c, the supply pump 8a, and the relief valve 8f to adjust the amount of hydraulic oil in the fluid chamber R3, whereby the piston rod 6 is Change the compression ratio by changing the position of

This engine system 100 causes the piston 4 to slide in the cylinder liner 3a by igniting and exploding the fuel injected into the combustion chamber R1 from a fuel injection valve (not shown) to rotate the crankshaft 11 . It is a device that makes In detail, the fuel supplied to the combustion chamber R1 is mixed with the air introduced from the scavenging port S, and is compressed as the piston 4 moves toward the top dead center, and the temperature rises to spontaneously ignite. In addition, in the case of liquid fuel, it vaporizes and spontaneously ignites by raising the temperature in combustion chamber R1.

And the fuel in the combustion chamber R1 expands rapidly by spontaneous ignition, and the pressure toward the bottom dead center is applied to the piston 4 . Thereby, the piston 4 moves in the bottom dead center direction, the piston rod 6 moves along the piston 4, and the crankshaft 11 is rotated via the connecting rod 9. As shown in FIG. In addition, when the piston 4 moves to the bottom dead center, pressurized air flows into the combustion chamber R1 from the scavenging port S. When the exhaust valve unit 5 is driven, the exhaust port H is opened, and the exhaust gas in the combustion chamber R1 is pushed out to the exhaust tank part 13 by the pressurized air.

When enlarging a compression ratio, the supply pump 8a is driven by the control part 300, and hydraulic oil is supplied to the plunger pump 8c. Then, the control unit 300 drives the plunger pump 8c to pressurize the hydraulic oil until it becomes a pressure capable of lifting the piston rod 6 , and supplies the hydraulic oil to the fluid chamber R3 . The flange 6c of the piston rod 6 is lifted by the pressure of the hydraulic oil in the fluid chamber R3, so that the top dead center position of the piston 4 is moved upward (exhaust port H side). .

When making the compression ratio small, the relief valve 8f is driven by the control part 300, and the fluid chamber R3 and the hydraulic oil tank (not shown) are in communication state. And the load of the piston rod 6 is applied to the hydraulic oil of the fluid chamber R3, and the hydraulic oil in the fluid chamber R3 is pushed out to the hydraulic oil tank via the relief valve 8f. Thereby, the hydraulic oil in the fluid chamber R3 decreases, the piston rod 6 moves downward (crankshaft 11 side), and the top dead center position of the piston 4 moves downwardly by this.

Next, the flow of hydraulic oil on the piston rod 6 side is demonstrated.

A part of the hydraulic oil supplied from the supply pump 8a passes through the cooling oil supply passage R6 and is supplied from the cover member 7c to the upper hydraulic chamber R7 as shown in FIG. 3 . Thereby, upper hydraulic chamber R7 will be in the state filled with hydraulic oil. Then, the hydraulic oil in the upper hydraulic chamber R7 flows into the outer oil passage R8 from the passage opening formed in the upper surface of the flange 6c of the piston rod 6 (the bottom surface of the upper oil pressure chamber R7), and the piston rod It is guided upward (compression direction) along (6), and is discharged to the inside of the piston 4 from the jet port 4a. When the hydraulic oil discharged to the inside of the piston 4 contacts the inner surface of the piston 4 , the piston 4 can be cooled. In addition, the hydraulic oil discharged to the inside of the piston 4 is guided to the inner flow path R9, discharged from the lower end of the piston rod 6, and discharged to the outside from the discharge port O.

According to this embodiment, hydraulic oil is supplied from above the upper oil pressure chamber R7, and an outer flow passage from a passage opening formed in the flange 6c of the piston rod 6 corresponding to the bottom surface of the upper oil pressure chamber R7. (R8). Thereby, when supplying hydraulic oil (cooling oil) to the piston 4, it is not necessary to form an opening in the outer peripheral surface (sliding surface with the crosshead pin 7a) of the flange 6c. Therefore, since there is no restriction on the thickness of the flange 6c, the amount of movement of the flange 6c within the crosshead pin 7a, that is, the amount of movement of the piston rod 6 by the variable compression mechanism can be sufficiently secured. .

Moreover, according to this embodiment, the hydraulic oil is supplied toward the upper hydraulic chamber R7 below from the opening of the cooling oil supply flow path R6 formed in the cover member 7c. Thereby, the hydraulic oil can be supplied irrespective of the position with respect to the crosshead pin 7a of the piston rod 6 by the change of a compression ratio.

[Second embodiment]

A modification of the first embodiment will be described with reference to FIG. 4 as a second embodiment. In addition, in this 2nd Embodiment, the structure common to 1st Embodiment makes a common code|symbol, and abbreviate|omits description. In addition, in FIG. 4, illustration of the structure of the hydraulic part 8 is abbreviate|omitted.

In this embodiment, in the flange 6c of the piston rod 6, a step-shaped notch is made on the surface (the upper surface of the flange 6c, the bottom surface of the upper hydraulic chamber R7) facing the cover member 7c. is formed. That is, the radial direction outer end part is cut out among the upper surfaces of the flange 6c. The opening of the outer flow path R8 is formed in the notch formed in the flange 6c of the piston rod 6 . Moreover, in this embodiment, although the opening of the outer side flow path R8 is formed in the bottom surface (surface facing upward) of the said notch, it may be formed in the side surface (surface facing radially outward) in the said notch. The cooling oil supply flow path R6 becomes a linear flow path from the radially outer side to the inside side of the piston rod 6 in the crosshead pin 7a, and is a side peripheral surface (crosshead pin) of the upper hydraulic chamber R7. A supply opening (opening end) is formed in the inner side of 7a), the inner surface of the said insertion recessed part. Moreover, the supply opening is formed in the upper side (near of the cover member 7c of the crosshead pin 7a) among the inner surfaces of the said insertion recessed part in an up-down direction. Accordingly, even when the piston rod 6 is moved in the high compression ratio direction (upward) and the flange 6c is in contact with (or close to) the cover member 7c, the cooling oil supply passage R6 is supplied. The opening faces the notch of the flange 6c, so that it can communicate with the outer oil passage R8 via the upper hydraulic chamber R7. In this case, it is not necessary to form the cooling oil supply flow path R6 in the cover member 7c, and it is easy to form the cooling oil supply flow path R6.

The variable compression device (A) of the above embodiment includes a piston rod (6) having a flange (6c) formed at an end thereof, and a fluid chamber (6) in which the piston rod (6) is moved in a direction to increase the compression ratio by supplying a pressurized working fluid ( R3), a cover member 7c provided on the opposite side to the fluid chamber R3 with the flange 6c interposed therebetween, and regulating the movement in the direction of increasing the compression ratio of the piston rod 6, and the flange 6c. An upper oil pressure chamber R7 formed between the flange 6c and the cover member 7c as the bottom surface, and a cooling oil supply passage R6 for supplying a cooling fluid (cooling oil) to the upper oil pressure chamber R7. and an outer flow path R8 having an open end on the bottom surface and guiding the cooling fluid in the upper hydraulic chamber R7 to the inside of the piston rod 6 .

The open end of the cooling oil supply flow path R6 may be formed on the surface of the cover member 7c opposite to the upper hydraulic chamber R7.

The variable compression device (A) of the above embodiment further includes a crosshead pin (7a) constituting the upper hydraulic chamber (R7) by inserting the end of the piston rod (6), a notch is formed in the bottom surface, , an open end of a cooling oil supply passage R6 is formed on a surface of the crosshead pin 7a opposite to the upper hydraulic chamber R7 (the inner surface of the insertion recess), and an outer passage R8 is formed in the notch ) may be formed.

The flange 6c may have a groove flow path in a region overlapping with the open end of the outer flow path R8.

The engine system 100 is equipped with the variable compression device A of the said embodiment.

As mentioned above, although preferred embodiment of this indication was described referring drawings, this indication is not limited to the said embodiment. The various shapes, combinations, etc. of each structural member shown in the above-mentioned embodiment are examples, and various changes are possible based on design request etc. in the range which does not deviate from the meaning of this indication.

In the above embodiment, in the flange 6c (the upper surface of the flange 6c) of the piston rod 6, a groove flow passage passing through a position overlapping with the flow passage opening of the outer flow passage R8 in plan view may be formed. . In this case, the hydraulic oil flowing into the upper hydraulic chamber R7 can be efficiently guided to the flow passage opening by the groove passage.

In addition, in the said 2nd Embodiment, although the notch formed in the flange 6c was said to be step-shaped, this indication is not limited to this. For example, the edge (radial outer edge) of the surface facing the cover member 7c of the flange 6c is cut out in a tapered shape, and the flow path opening of the outer flow path R8 may be formed on the tapered surface. . Also in this case, it is possible to acquire the effect similar to the said 2nd Embodiment.

In addition, in the said embodiment, although hydraulic oil is supplied to upper hydraulic chamber R7 as cooling oil from the supply pump 8a, this indication is not limited to this. For example, a cooling oil pump may be provided as a body separate from the supply pump 8a, and cooling oil may be supplied as a system separate from the hydraulic oil.

1 engine
2 furniture
3 cylinder part
3a cylinder liner
3b cylinder head
3c cylinder jacket
4 piston
4a vent
5 exhaust valve unit
5a exhaust valve
5b exhaust valve casing
5c exhaust valve actuator
6 piston rod
6a Appearance
6b interior
6c flange
7 cross head
7a Cross head pin (fluid chamber forming member)
7b guide shoe
7c cover member (regulatory member)
8 Hydraulics
8a feed pump
8b swing tube
8c plunger pump
8c1 plunger
8c2 cylinder
8c3 plunger drive
8d first check valve
8e 2nd check valve
8f relief valve
8f1 body
8f2 relief valve actuator
9 connecting rod
10 crank angle sensor
11 crankshaft
12 Scavenging tank part
13 exhaust tank
14 air cooler
100 engine system
200 supercharger
300 control
A variable compression device
H exhaust port
O outlet
R1 combustion chamber
R2 scavenging chamber
R3 fluid chamber
R4 Supply Euro
R5 relief euro
R6 Cooling oil supply flow path (supply flow path)
R7 Upper hydraulic chamber (regulator side fluid chamber)
R8 Outer channel (piston rod inner channel)
R9 inner flow path
S scavenging port

Claims (5)

A piston rod having a flange formed at the end, and
A fluid chamber in which the piston rod is moved in a direction to increase the compression ratio by supplying the pressurized working fluid;
a regulating member provided on the opposite side to the fluid chamber with the flange interposed therebetween to regulate movement in a direction to increase the compression ratio of the piston rod;
a regulating member-side fluid chamber formed between the flange and the regulating member with an upper surface of the flange as a bottom;
a supply passage for supplying a cooling fluid to the regulating member-side fluid chamber;
A variable compression device having an open end on an upper surface of the flange, which is a bottom surface of the regulating member-side fluid chamber, and a piston rod internal flow path for guiding the cooling fluid in the regulating member-side fluid chamber to the inside of the piston rod . The method according to claim 1,
An open end of the supply passage is formed on a surface of the regulating member opposite to the regulating member-side fluid chamber. The method according to claim 1,
a fluid chamber forming member constituting the regulating member side fluid chamber by inserting the end of the piston rod;
A notch is formed in the bottom surface,
An open end of the supply passage is formed on a surface of the fluid chamber forming member opposite to the regulating member-side fluid chamber;
In the notch, an open end of the piston rod internal flow path is formed. 4. The method according to any one of claims 1 to 3,
The flange has a variable compression device having a groove passage in a region overlapping an open end of the piston rod inner passage. An engine system comprising the variable compression device according to any one of claims 1 to 3.

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