JP2022178606A - Cylinder oil-filling system - Google Patents

Abstract

To provide a cylinder oil-filling system which can efficiently fill a piston reciprocating in a cylinder with a lubricant.SOLUTION: A cylinder oil-filling system being one embodiment of this invention comprises: an oil syringe for filling a piston reciprocating in a cylinder of a marine internal combustion engine with a lubricant through an oil-filling rod arranged at the cylinder; an electromagnetic valve for accumulating the lubricant in the oil syringe in a closed state, and making the oil syringe fill the piston with the lubricant in an open state; and a control device. The control device derives an oil-filling rate of the lubricant according to an engine load, decides an oil-filling frequency and the oil-filling timing of the lubricant to a piston upper side part of the piston and a skirt part at the derived oil-filling rate, and controls the opening/closing drive of the electromagnetic valve so that the oil syringe fills the piston with the lubricant at the decided oil-filling frequency and the oil-filling timing.SELECTED DRAWING: Figure 1

Description

The present invention relates to cylinder lubrication systems.

2. Description of the Related Art Conventionally, an engine mounted on a ship (marine internal combustion engine) is provided with a plurality of cylinders that accommodate pistons so as to be capable of reciprocating motion. , the crankshaft rotates. Generally, in a marine internal combustion engine, each time a piston reciprocates inside a cylinder, combustion gas is compressed and fuel is burned in a combustion chamber. A piston is housed in a cylinder so that its crown (piston crown) faces the combustion chamber, and reciprocates inside the cylinder while receiving pressure in the combustion chamber (hereinafter referred to as cylinder pressure).

A plurality of piston rings arranged in the reciprocating direction of the piston are provided on the outer peripheral portion of such a piston. The plurality of piston rings are in sliding contact with the inner peripheral surface of the cylinder while applying appropriate surface pressure, and slide on the inner peripheral surface of the cylinder as the piston reciprocates. Further, the piston has a skirt portion (piston skirt) below the lowest piston ring among the plurality of piston rings. In general, due to its structure, the piston may tilt while reciprocating inside the cylinder. This tilting of the piston is restricted by the sliding contact between the inner peripheral surface of the cylinder and the skirt portion.

As described above, lubricating oil is supplied (injected) between the piston that reciprocates inside the cylinder and the inner peripheral surface of the cylinder in order to ensure the slidability of the piston with respect to the inner peripheral surface of the cylinder. be. For example, in Patent Document 1, based on the crank angle and engine speed of a two-cycle engine, a first lubricating period for injecting oil into the cylinder while the piston is rising is adjusted, and when the engine speed decreases, the first lubricating period is adjusted. If it is not possible to lubricate the lower part of the piston ring below the lowest piston ring within the lubricating period of , supplementary lubricating method is described in which lubrication is lubricated to the lower part of the piston during the second lubricating period after the first lubricating period. there is

JP-A-2013-83228

By the way, generally speaking, the higher the in-cylinder pressure applied to the crown during the reciprocating motion, the more stable the posture of the piston in the cylinder and the less likely it is to tilt. Easy to lean. Therefore, in order to ensure the slidability of the piston with respect to the inner peripheral surface of the cylinder, lubricating oil must be injected so that an oil film is formed between the inner peripheral surface of the cylinder and the piston ring. When the skirt portion slides on the inner peripheral surface of the cylinder as it tilts, it is necessary to supply lubricating oil so that an oil film is formed between the inner peripheral surface of the cylinder and the skirt portion.

However, in the lubricating method described in Patent Document 1 described above, the period and timing for lubricating oil to the piston in the cylinder are controlled according to the engine speed. Even if it is difficult to do so, there is a possibility that lubricating oil will be wasted on the skirt portion, so it is difficult to efficiently lubricate the piston in the cylinder with lubricating oil.

In other words, regardless of whether the engine speed is high or low, if the load on the marine internal combustion engine (hereinafter referred to as "engine load") increases or decreases due to the influence of sea conditions on the ship underway, the pressure in the cylinders of the marine internal combustion engine will can increase or decrease accordingly. For example, even if the engine speed decreases, if the engine load increases due to the influence of sea conditions, the in-cylinder pressure increases, making it difficult for the piston to tilt within the cylinder. In the lubricating method described in Patent Document 1, even if the piston is difficult to tilt as described above (that is, contact between the inner peripheral surface of the cylinder and the skirt portion is difficult to occur), the engine speed Lubricating oil is wasted to the skirt portion based on the decrease.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a cylinder lubricating system capable of efficiently injecting lubricating oil into a piston that reciprocates inside a cylinder.

In order to solve the above-described problems and achieve the object, a cylinder lubricating system according to the present invention supplies lubricating oil to a piston reciprocating inside a cylinder of a marine internal combustion engine through a lubricating rod provided in the cylinder. a solenoid valve that accumulates the lubricating oil in the lubricator in the closed state and causes the lubricator to inject the lubricating oil into the piston in the open state; Deriving the lubrication rate of the lubricating oil according to the load of the internal combustion engine, determining the frequency and timing of lubrication of the lubricating oil to each of the piston upper part and the skirt part of the piston at the derived lubrication rate, a control device for controlling the opening/closing drive of the electromagnetic valve so that the lubricating oil is lubricated by the lubricating oil at the determined lubricating frequency and lubricating timing.

Further, in the cylinder lubricating system according to the present invention, in the above invention, the control device is configured such that the lubricating oil feeding rate to the skirt portion is constant with respect to the lubricating oil feeding rate to the upper portion of the piston. The frequency and timing of lubricating oil injection into the piston upper portion and the frequency and timing of lubricating oil injection into the skirt portion are determined so as to be proportionate.

Further, in the cylinder lubricating system according to the present invention, in the above invention, the control device sets the lubricating oil feeding rate when the load of the marine internal combustion engine is 100% as a reference lubricating rate. The lubricating oil feeding rate corresponding to the load of the marine internal combustion engine is derived based on the reference lubricating oil feeding rate.

Further, in the cylinder lubricating system according to the present invention, in the above invention, an input unit for inputting a designated value for designating the reference lubricating rate to be changeable to the control device, the control device The reference lubricating rate is set based on the specified value.

Further, in the cylinder lubricating system according to the present invention, in the above invention, an input unit for inputting permission information for permitting lubricating of the lubricating oil to the skirt portion into the control device, the control device comprising: It is characterized in that the supply of the lubricating oil to the skirt portion is permitted based on the input permission information.

Further, in the cylinder lubricating system according to the present invention, in the above invention, the control device lubricates the lubricating oil to the piston for each cycle included in a fixed cycle period in which one reciprocating motion of the piston is one cycle. and whether to lubricate the piston upper portion or the skirt portion when lubricating oil is to be lubricated.

Further, in the cylinder lubrication system according to the present invention, in the above invention, the control device controls the upper portion of the piston that is ascending or the position of the piston that is descending based on the crank angle of the marine internal combustion engine. The opening/closing drive of the solenoid valve is controlled so that the lubricating oil is injected into the skirt portion by the lubricating device.

ADVANTAGE OF THE INVENTION According to this invention, it is effective in being able to lubricate efficiently lubricating oil with respect to the piston which reciprocates the inside of a cylinder.

FIG. 1 is a schematic diagram showing one configuration example of a cylinder lubricating system according to an embodiment of the present invention. FIG. 2 is a schematic diagram showing an example of arrangement of lubricating rods in the embodiment of the present invention. FIG. 3 is a schematic diagram showing an example of a first data table used for lubricating control of the piston upper portion in the embodiment of the present invention. FIG. 4 is a schematic diagram showing an example of a second data table used for lubrication control for the skirt portion according to the embodiment of the present invention. FIG. 5 is a schematic diagram showing an example of lubrication to the piston upper portion 5a according to the embodiment of the present invention. FIG. 6 is a schematic diagram showing an example of lubricating the piston skirt in the embodiment of the present invention. FIG. 7 is a flow chart showing an example of a processing flow of lubricating control by the cylinder lubricating system according to the embodiment of the present invention.

A preferred embodiment of a cylinder lubricating system according to the present invention will be described in detail below with reference to the accompanying drawings. It should be noted that the present invention is not limited by this embodiment. Also, it should be noted that the drawings are schematic, and the dimensional relationship of each element, the ratio of each element, and the like may differ from the actual ones. Even between the drawings, there are cases where portions with different dimensional relationships and ratios are included. Also, in each drawing, the same components are denoted by the same reference numerals.

(Configuration of cylinder lubrication system)
FIG. 1 is a schematic diagram showing one configuration example of a cylinder lubricating system according to an embodiment of the present invention. This cylinder lubricating system 10 injects lubricating oil into a piston 5 reciprocating inside a cylinder 1 of a marine internal combustion engine to ensure slidability of the piston 5 with respect to the inner peripheral surface 2a of the cylinder 1. It is a thing. Although not shown in particular, the marine internal combustion engine is a propulsion engine mounted on a ship and rotationally driving a propulsion propeller of the ship via a propeller shaft. It is a 2-stroke diesel engine. Cylinder 1 is an example of a plurality of cylinders provided in a marine internal combustion engine. Cylinder lubrication system 10 lubricates each of the plurality of cylinders with lubricating oil in the same manner as cylinder 1 shown in FIG.

Specifically, as shown in FIG. 1 , the cylinder 1 is a tubular structure (cylinder) composed of a cylinder liner 2 and a cylinder cover 3 . The cylinder 1 accommodates a piston 5 inside a cylindrical cylinder liner 2 so as to be able to reciprocate. A cylinder cover 3 is fixed to the upper portion of the cylinder liner 2 . A combustion chamber 4 of the marine internal combustion engine is formed (divided) inside the cylinder 1 by the cylinder liner 2 , the cylinder cover 3 , and the piston 5 . Further, the cylinder cover 3 is provided with an exhaust valve 9 . The exhaust valve 9 is a valve that opens and closes an exhaust port communicating with the combustion chamber 4 in the cylinder 1 .

The piston 5, as shown in FIG. 1, comprises a piston body 6 and three piston rings 7a, 7b, 7c. Although this embodiment exemplifies the piston 5 having three piston rings 7a, 7b, and 7c, the present invention is not limited to this, and the piston 5 includes a plurality of (two or more) piston rings. A ring may also be provided.

As shown in FIG. 1, the piston body 6 includes a crown portion 6a, a skirt portion 6b, and an intermediate portion 6c, and is formed in a circular shape when viewed from the central axis direction of the cylinder liner 2. As shown in FIG. The piston rings 7 a , 7 b , 7 c are each fitted into an annular groove provided in the outer peripheral portion of the intermediate portion 6 c located between the crown portion 6 a and the skirt portion 6 b of the piston body 6 . It is configured to be in sliding contact with the surface 2a while applying an appropriate surface pressure. The crown portion 6a is a portion of the piston body 6 above the uppermost piston ring 7a (on the side opposite to the skirt portion 6b), and is also called a piston crown. The piston body 6 is housed inside the cylinder liner 2 of the cylinder 1 so that the crown portion 6a faces the combustion chamber 4 so as to be able to reciprocate. The skirt portion 6b is a portion of the piston body 6 below the lowermost piston ring 7c (opposite to the crown portion 6a), and is also called a piston skirt.

As shown in FIG. 1, one end of a piston rod 8 is rotatably connected to the piston body 6 . Although not shown, the other end of the piston rod 8 is rotatably connected to a crosshead, to which one end of a connecting rod is rotatably connected. The other end of this connecting rod is rotatably connected to the crank of the crankshaft.

In a marine internal combustion engine, as shown in FIG. 1, a piston 5 receives cylinder internal pressure of a combustion chamber 4 on a crown portion 6a while piston rings 7a, 7b, and 7c are in sliding contact with an inner peripheral surface 2a of a cylinder 1. reciprocating motion between the top dead center Ct and the bottom dead center Cb in the cylinder 1. Each time the piston 5 reciprocates inside the cylinder 1, the combustion gas is introduced into the combustion chamber 4, the combustion gas is compressed, and the fuel supplied to the combustion chamber 4 is burned. , the exhaust from the combustion chamber 4 is performed sequentially. Such reciprocating motion of the piston 5 is converted into rotary motion of the crank through the piston rod 8 and the like. As a result, the crankshaft rotates, which rotates the ship's propulsion propeller along with the propeller shaft.

Further, when the piston 5 reciprocates inside the cylinder 1 , the piston 5 may tilt with respect to the central axis of the cylinder 1 . In this case, the skirt portion 6b contacts the inner peripheral surface 2a of the cylinder liner 2, thereby suppressing the tilting of the piston 5. As shown in FIG. The piston 5 returns from the tilted posture to the posture before tilting while continuing the reciprocating motion inside the cylinder 1 . Note that the tilting of the piston 5 tends to occur less easily as the in-cylinder pressure applied to the crown portion 6a increases, and tends to occur more easily as the in-cylinder pressure applied to the crown portion 6a decreases.

On the other hand, the cylinder lubricating system 10 includes a lubricating rod 11, a lubricator 12, an electromagnetic valve 13, an oiling unit 14, an operating device 15, and a control device 16, as shown in FIG. In addition, in FIG. 1 , the solid arrows schematically indicate the circulation and piping of the lubricating oil. A dashed-dotted arrow schematically indicates an electric signal line.

The lubricating rod 11 is positioned between the top dead center Ct and the bottom dead center Cb in the reciprocating motion of the piston 5, as shown in FIG. It is provided in the liner 2. Also, the lubricating rod 11 is connected to a lubricator 12 through a pipe so that the inside of the cylinder 1 and the lubricator 12 can communicate with each other. 1 shows one lubricating rod 11 for convenience of explanation, but in the cylinder lubricating system 10, a plurality of lubricating rods 11 are provided in the cylinder liner 2. As shown in FIG.

FIG. 2 is a schematic diagram showing an example of arrangement of lubricating rods in the embodiment of the present invention. FIG. 2 schematically shows a cross section of the cylinder liner 2 shown in FIG. In addition, in FIG. 2, the solid line arrows schematically indicate the circulation and piping of the lubricating oil. As shown in FIG. 2 , a plurality of (eight in this embodiment) lubricating rods 11 are arranged in the cylinder liner 2 at intervals in the circumferential direction of the cylinder liner 2 . These plurality of lubricating rods 11 are each connected to a lubricator 12 through a pipe so that the interior of the cylinder liner 2 and the lubricator 12 can communicate with each other. The arrangement intervals of the plurality of lubricating rods 11 may be any desired intervals, but are preferably equal intervals.

The lubricator 12 injects lubricating oil into the piston 5 reciprocating inside the cylinder 1 of the marine internal combustion engine through the lubricating rod 11 provided in the cylinder 1 . Specifically, as shown in FIG. 1, the lubricator 12 is communicably connected to each of the lubricating rod 11 and the lubricating unit 14 through a plurality of pipes. The lubricator 12 has therein an oil storage chamber (not shown) communicating with these pipes, and stores lubricating oil supplied from the oil supply unit 14 in the oil storage chamber. Also, the lubricator 12 has, for example, a hydraulic plunger (not shown) or the like, and pumps out lubricating oil accumulated in the oil storage chamber. As a result, the lubricator 12 pressure-feeds the lubricating oil to the lubricating rod 11 through the pipe, and injects the lubricating oil from the lubricating rod 11 to the piston 5 in the cylinder 1 . For example, the lubricator 12 discharges a certain amount of lubricating oil from each of the plurality of lubricating rods 11 per lubricating operation.

The solenoid valve 13 is a valve for causing the lubricator 12 to appropriately inject or accumulate lubricating oil. Specifically, as shown in FIG. 1 , the solenoid valve 13 is provided in a pipe leading to the lubricator 12 . This pipe is, for example, a branch pipe branched from the pipe connecting the lubricator 12 and the lubricating unit 14 . The solenoid valve 13 is driven and controlled by a control device 16, and is in an open state in which the lubricator 12 and the lubricating unit 14 are communicated through the branch pipe, and in a closed state in which communication between the lubricator 12 and the lubricating unit 14 is closed through the branch pipe. and either state. For example, the solenoid valve 13 is normally closed, and is opened when receiving a control signal for an operation command from the control device 16 . When the solenoid valve 13 is closed, the lubricating oil supplied from the lubricating unit 14 is accumulated in the lubricator 12 . Further, when the electromagnetic valve 13 is in the open state, the lubricator 12 causes the lubricating oil to be injected into the piston 5 in the cylinder 1 .

The lubricating unit 14 supplies the lubricating oil to the lubricator 12 to lubricate the piston 5 in the cylinder 1 through the lubricating rod 11 . Specifically, the lubricating unit 14 is composed of a pump, a pressure regulating valve, etc., and is communicably connected to the oil storage chamber of the lubricator 12 through a pipe, as shown in FIG. Also, the lubricating unit 14 is communicably connected to an operating chamber (not shown) of the lubricator 12 through a branch pipe branched from this pipe and the solenoid valve 13 . When the electromagnetic valve 13 is closed, the lubricating unit 14 feeds the pressure-regulated lubricating oil to the oil storage chamber of the lubricator 12 through the pipe. This lubricating oil is stored in the reservoir chamber of the lubricator 12 for lubricating the piston 5 in the cylinder 1 . In addition, when the electromagnetic valve 13 is open, the lubricating unit 14 feeds the pressure-regulated lubricating oil to the working chamber of the lubricator 12 through the branch pipe. This lubricating oil is used, for example, as hydraulic oil for causing the lubricating device 12 to perform lubricating operation by operating a hydraulic cylinder or the like.

The operation device 15 includes a display device, an input device, and the like, and displays various types of information on the display screen and transmits the information to the control device in accordance with user's input operations. For example, the operating device 15 has a function as a first input unit for inputting a designated value for designating a changeable reference lubricating oil rate to the control device 16 . The reference lubricating rate is a reference value for the lubricating rate that the control device 16 derives during lubricating control. The specified value of the reference lubricating rate is input so as to be changeable within a permissible range based on the specifications of the marine internal combustion engine. The operation device 15 also functions as a second input section for inputting permission information to the control device 16 for permitting the injection of lubricating oil into the skirt portion 6 b of the piston 5 . This permission information is input when permitting the control device 16 to apply lubricating oil to the skirt portion 6b.

The control device 16 controls the injection of lubricating oil to the piston 5 inside the cylinder 1 . For example, the control device 16 is configured by a CPU, a memory, etc., and has a central control section 17 and a drive control section 19 for executing lubrication control, as shown in FIG. In addition, the central control unit 17 has a first data table 18a showing the correspondence relationship between the lubricating oil injection rate for the piston upper part 5a, the lubricating frequency, and the lubricating timing, and the lubricating oil injection rate for the skirt part 6b of the piston 5. , and a second data table 18b showing the corresponding relationship between the lubricating frequency and the lubricating timing are registered in advance by programming or the like. The piston upper portion 5a is a portion of the piston 5 above the skirt portion 6b, as shown in FIG. For example, the piston upper portion 5a includes the crown portion 6a, the intermediate portion 6c and the piston rings 7a-7c of the piston 5. As shown in FIG.

The central control unit 17 derives the lubricating oil injection rate for the piston 5 according to the load (engine load) of the marine internal combustion engine, and the piston upper portion 5a and the skirt portion 6b of the piston 5 at the derived lubrication rate. Determine the lubrication frequency and lubrication timing for each.

Specifically, the central control unit 17 sets the lubricating oil injection rate for the piston 5 when the engine load is 100% as the reference oil injection rate. For example, the central control unit 17 sets the maximum lubricating rate (hereinafter referred to as maximum lubricating rate) among the plurality of lubricating rates included in the first data table 18a as the reference lubricating rate. Alternatively, when a designated value of the reference lubricating rate is input to the control device 16 by the operating device 15, the central control unit 17 sets the reference lubricating rate based on the input designated value.

The central control unit 17 derives the lubricating oil filling rate corresponding to the engine load based on the reference oil filling rate set as described above. At this time, the central control unit 17 derives the oil supply rate for each operating mode of the marine internal combustion engine. For example, when the operating mode of the marine internal combustion engine is the mean effective pressure proportional mode, the central control unit 17 detects the engine speed detected by the speed detector 22 and the engine load detected by the load detector 23. Based on this, the average effective pressure of the marine internal combustion engine is calculated. The central control unit 17 obtains the ratio of the calculated average effective pressure to the average effective pressure when the engine load is 100%, and multiplies this ratio by the reference oil supply rate to determine the oil supply rate according to the engine load. derive Alternatively, when the operation mode of the marine internal combustion engine is the output proportional mode, the central control unit 17 multiplies the engine load detected by the load detector 23 by the reference oil supply rate, or the like, to determine the oil supply rate according to the engine load. derive

Further, the central control unit 17 refers to the first data table 18a and the second data table 18b, and determines the frequency and timing of lubricating oil injection to the piston 5 based on the derived lubricating rate. Specifically, the central control unit 17 sets the lubricating frequency and lubricating timing corresponding to the derived lubricating rate among the lubricating frequency and lubricating timing shown in the first data table 18a. Determined as lubricating frequency and lubricating timing. Further, the central control unit 17 selects the lubricating frequency and the lubricating timing corresponding to the constant ratio of the derived lubricating rate from among the lubricating frequency and the lubricating timing shown in the second data table 18b. It is determined as the lubricating frequency and the lubricating timing. That is, the central control unit 17 supplies the lubricating oil to the piston upper part 5a so that the lubricating oil to the skirt part 6b has a constant ratio with respect to the lubricating oil to the piston upper part 5a. The frequency and timing of lubrication, and the frequency and timing of lubricating oil to the skirt portion 6b are determined. The central control unit 17 instructs the drive control unit 19 on the lubrication frequency and lubrication timing determined as described above.

In this embodiment, when one reciprocating motion of the piston 5 inside the cylinder 1 is defined as one cycle, lubrication performed within one cycle of the piston 5 (hereinafter referred to as a piston cycle) is lubrication to the piston upper portion 5a. or lubrication to the skirt portion 6b. Therefore, the frequency of lubricating oil injection into the piston upper portion 5a is the number of piston cycles in which lubricating oil is injected into the piston upper portion 5a within a certain period including a plurality of piston cycles (hereinafter referred to as a certain cycle period). represented by Similarly, the frequency of lubricating oil to the skirt portion 6b is represented by the number of piston cycles during which the skirt portion 6b is lubricated within a certain cycle period.

In addition, the lubricating oil injection timing to the piston upper portion 5a is represented by specific information specifying each of a plurality of piston cycles included in a fixed cycle period and the crank angle corresponding to the piston upper portion 5a. Similarly, the lubrication timing of the lubricating oil to the skirt portion 6b is represented by the specific information of each piston cycle within a fixed cycle period and the crank angle corresponding to the skirt portion 6b. The crank angle corresponding to the piston upper portion 5a is the crank angle of the marine internal combustion engine when the piston upper portion 5a reaches the position facing the oil inlet of the oil rod 11 arranged in the cylinder liner 2. The crank angle corresponding to the skirt portion 6b is the crank angle of the marine internal combustion engine when the skirt portion 6b reaches the position facing the lubricating port of the lubricating rod 11. FIG.

That is, in this embodiment, the central control unit 17 determines whether or not to lubricate the piston 5 with lubricating oil for each piston cycle included in a fixed cycle period in which one reciprocating motion of the piston 5 is one cycle. . In addition, when lubricating oil is injected into the piston 5, the central control unit 17 determines for each piston cycle whether the piston upper portion 5a or the skirt portion 6b is to be lubricated.

In addition, in the present embodiment, the central control unit 17 may permit or prohibit the injection of lubricant to the skirt portion 6b among the injection of the lubricant to the piston 5 based on the user's operation. For example, when permission information for lubricating the skirt portion 6b is input to the control device 16 by the operating device 15, the central control portion 17 lubricates the skirt portion 6b with lubricating oil based on the input permission information. allow In this case, the central control unit 17 permits the drive control unit 19 to apply lubricating oil to the skirt portion 6b by, for example, setting a permission flag.

The drive control unit 19 controls the opening/closing drive of the solenoid valve 13 so that the lubricator 12 injects lubricating oil at the lubrication frequency and lubrication timing determined by the central control unit 17 as described above. Specifically, based on the crank angle of the marine internal combustion engine detected by the angle detector 21, the drive control unit 19 starts the opening drive at the lubrication timing instructed by the central control unit 17 for the piston upper part 5a. Then, the solenoid valve 13 is controlled so that the open state is maintained for a predetermined period and driven to close. In addition, the drive control unit 19 receives an instruction from the central control unit 17 regarding the skirt portion 6b based on the crank angle of the marine internal combustion engine detected by the angle detector 21 in a piston cycle different from that of the piston upper portion 5a. The solenoid valve 13 is controlled so that the open drive is started at the timing of lubrication, the open state is maintained for a predetermined period, and the solenoid valve 13 is closed. Every time the central control unit 17 instructs the lubricating frequency and the lubricating timing, the drive control unit 19 repeatedly controls the opening and closing of the solenoid valve 13 with the instructed lubricating frequency as the upper limit. When the driving control of the electromagnetic valve 13 is repeatedly performed up to the instructed lubricating frequency, the driving control unit 19 again performs the control of the opening/closing driving of the electromagnetic valve 13 again within a fixed cycle period.

For example, during each piston cycle during which lubricating oil is injected into the piston 5 within a certain cycle period, the drive control unit 19 detects the crank angle of the marine internal combustion engine detected by the angle detector 21. The opening/closing drive of the solenoid valve 13 is controlled so that the lubricator 12 injects lubricating oil into either the piston upper portion 5a of the piston 5 in the middle or the skirt portion 6b of the piston 5 during the descent. In this embodiment, whether the piston 5 is ascending or descending inside the cylinder 1 can be specified by the rotation angle (crank angle) of the crank that rotates along with the reciprocating motion of the piston. . For example, when the crank angle when the piston 5 is positioned at the top dead center Ct in the cylinder 1 is taken as a reference (=0 degrees), the crank angle when the piston 5 is positioned at the bottom dead center Cb in the cylinder 1 is 180 degrees. When the piston 5 is moving (that is, descending) from the top dead center Ct side to the bottom dead center Cb side, the crank angle is an angle between 0 degrees and 180 degrees. When the piston 5 is moving (that is, rising) from the bottom dead center Cb side to the top dead center Ct side, the crank angle is an angle between 180 degrees and 360 degrees.

Further, if the central control unit 17 permits the supply of lubricating oil to the skirt portion 6b, the drive control unit 19 controls the opening/closing drive of the electromagnetic valve 13 at the oil injection timing for the skirt portion 6b. On the other hand, if the injection of lubricating oil from the central control unit 17 to the skirt portion 6b is not permitted, the drive control unit 19, even if the lubricating timing for the skirt portion 6b is instructed, controls the electromagnetic The opening/closing driving of the valve 13 is not controlled.

Further, the drive control unit 19 causes the solenoid valve 13 in the open state to close based on the temperature of the lubricating oil detected by the temperature detector 24 and the pressure of the lubricating oil detected by the pressure detector 25. Control timing. As a result, the drive control unit 19 opens the solenoid valve 13 according to the state change such as the viscosity of the lubricating oil so that the lubricating oil injection amount per one lubricating operation by the lubricator 12 is constant. It is possible to correct the time from driving to closing driving. The time from when the solenoid valve 13 is driven to open until it is driven to close is the time during which the solenoid valve 13 remains open, and corresponds to the time during which the lubricating oil is injected into the piston 5 by the lubricator 12 .

The angle detector 21 detects the crank angle of the marine internal combustion engine. Specifically, the angle detector 21 continuously or intermittently detects the crank angle that changes with the reciprocating motion of the piston 5 inside the cylinder 1 along the time series. The angle detector 21 transmits an electric signal indicating the detected crank angle to the control device 16 each time it detects the crank angle. A plurality of such angle detectors 21 are provided in the marine internal combustion engine, for example, corresponding to the plurality of cylinders of the marine internal combustion engine.

The rotation speed detector 22 is provided in the marine internal combustion engine and detects the engine rotation speed of the marine internal combustion engine. For example, the rotation speed detector 22 continuously or intermittently detects the engine rotation speed in time series, and transmits an electric signal indicating the detected engine rotation speed to the control device 16 each time.

The load detector 23 is provided in the marine internal combustion engine and detects the engine load of the marine internal combustion engine. For example, the load detector 23 continuously or intermittently detects the engine load along the time series. Alternatively, the load detector 23 detects a plurality of engine loads for each predetermined period and calculates an average value of the detected engine loads. The load detector 23 acquires the average value of the engine load detected or calculated as described above as the current engine load of the marine internal combustion engine, and controls an electric signal indicating the acquired engine load each time. Send to device 16 .

The temperature detector 24 is provided, for example, in the lubricator 12 or the lubricating unit 14, and continuously or intermittently detects the temperature of lubricating oil lubricated to the piston 5 in chronological order. Each time the temperature detector 24 detects the temperature of the lubricating oil, it sends an electrical signal indicating the detected temperature to the control device 16 . The pressure detector 25 is provided, for example, in the lubricator 12 or the lubricating unit 14, and continuously or intermittently detects the pressure of lubricating oil injected into the piston 5 in time series. The pressure detector 25 transmits an electrical signal indicating the detected pressure to the control device 16 each time it detects the pressure of the lubricating oil.

(data table)
Next, the first data table 18a and the second data table 18b used for lubricating control in the embodiment of the present invention will be described in detail. FIG. 3 is a schematic diagram showing an example of a first data table used for lubricating control of the piston upper portion in the embodiment of the present invention. As shown in FIG. 3, the first data table 18a shows the correspondence between the lubricating rate _QN [g/kWh], the lubricating frequency N [times], and the lubricating timing _TN when lubricating oil is injected into the piston upper portion 5a. It is a data table showing relationships.

Specifically, in the first data table 18a shown in FIG. 3, the lubricating frequency N is the lubricating frequency at each of the plurality of lubricating rates registered as the lubricating rate _QN for the piston upper portion 5a. It is a numerical value that indicates the lubricating frequency). Numerical values of the lubricating frequency N include the maximum lubricating frequency N _a and each numerical value that decreases by one starting from the maximum lubricating frequency N a . The maximum lubricating frequency N _a is the maximum value among a plurality of numerical values registered as the lubricating frequency N in the first data table 18a.

The lubricating rate Q _N consists of a plurality of lubricating rates associated with each numerical value of the lubricating frequency N described above. For example, as shown in FIG. 3, the maximum lubricating frequency N _a is associated with the maximum lubricating rate Q _a , and the lubricating frequency N _a −1 obtained by subtracting 1 from the maximum lubricating frequency N _a corresponds to the lubricating rate Q ₁ . The lubricating frequency N _a -2 obtained by subtracting 1 from this lubricating frequency N _a -1 is associated with the lubricating rate Q ₂ . Such an oil supply rate Q _N is calculated by the following equation (1).

Lubricating rate Q _N = (maximum lubricating rate Q _a /maximum lubricating frequency N _a ) x lubricating frequency N (1)

In the above equation (1), for example, when the lubricating frequency N is the lubricating frequency N _a -1, the lubricating rate Q ₁ is calculated as the lubricating rate Q _N . When the lubricating frequency N is the lubricating frequency N _a -2, the lubricating rate Q ₂ is calculated as the lubricating rate Q _N .

As shown in FIG. 3, such a lubrication rate _QN includes a maximum lubrication rate _Qa , an upper limit lubrication rate _Qb , a lower lubrication rate _Qc, and the like. The maximum lubricating rate _Qa is the maximum lubricating rate among the plurality of lubricating rates registered in the first data table 18a. The upper limit lubricating rate _Qb is the upper limit of the lubricating rate when lubricating oil is injected into each of the piston upper portion 5a and the skirt portion 6b. The lower limit lubricating rate _Qc is the minimum lubricating rate required to ensure the lubricity of the piston 5 with respect to the inner peripheral surface 2a of the cylinder 1 when lubricating oil is injected into the piston upper portion 5a.

Of the lubricating frequencies N in the first data table 18a, the lubricating frequency _Nb is the lubricating frequency corresponding to the upper limit lubricating rate _Qb , and the lubricating frequency _Nc is the lubricating frequency corresponding to the lower lubricating rate _Qc . The lubricating frequency N _a /2 (the lubricating frequency that is 1/2 the maximum lubricating frequency N _a ) is the lubricating frequency that corresponds to the lubricating rate Q _a /2 (the lubricating rate that is 1/2 the maximum lubricating rate Q _a ). be.

Further, in the first data table 18a shown in FIG. 3, the lubricating timing T _N is the lubricating timing of lubricating oil to the piston upper portion 5a. Specifically, as shown in FIG. 3, the lubricating timing T _N is determined by the cycle number Y of the piston cycle, in which one reciprocating motion of the piston 5 inside the cylinder 1 is one cycle, and the crank angle corresponding to the upper part 5a of the piston. It is represented by a combination with A. Cycle number Y is a number specifying each of a plurality of piston cycles included in a fixed cycle period, and indicates the chronological order of these plurality of piston cycles. Cycle numbers Y are registered from 1 to Y _e as shown in FIG. 3 along the time series order of a plurality of piston cycles within a fixed cycle period. Cycle number Y _e is a number specifying the last piston cycle within a fixed cycle period. For example, the cycle number Y _e is the same numerical value as the maximum lubricating frequency N _a described above. The crank angle A corresponds to the lubrication timing for each piston cycle in which the piston upper portion 5a is lubricated. That is, in the first data table 18a, "yes" and "no" indicate whether or not the piston upper portion 5a is lubricated for each piston cycle. In the "present" piston cycle, oil is injected to the piston upper portion 5a at the timing when the crank angle of the marine internal combustion engine becomes "A". In the "none" piston cycle, the piston upper part 5a is not lubricated. The number of "present" piston cycles included in the constant cycle period of the lubricating timing _TN is the frequency of lubricating the piston upper portion 5a within the constant cycle period, and is represented by the lubricating frequency N described above. .

Such lubricating timing T _N is associated with lubricating frequency N and lubricating rate Q _N as shown in FIG. For example, when the lubricating rate Q _N is the maximum lubricating rate Q _a , the lubricating frequency N is the maximum lubricating frequency _Na , and the lubricating timing T _N is the lubricating timing at the maximum lubricating frequency _Na . In this case, lubrication to the piston upper part 5a is "present" in all piston cycles of cycle numbers 1 to Y _e . When the lubricating rate Q _N is the lubricating rate Q ₁ , the lubricating frequency N is the lubricating frequency N _a −1, and the lubricating timing T _N is the lubricating timing at this lubricating frequency N _a −1. In this case, lubrication to the piston upper part 5a is performed in the order of the cycle number Y: "yes" → "yes" → "yes" → "no" → "yes" → "yes" → "yes" → "yes", . . .→“Yes” When the lubricating rate Q _N is the upper limit lubricating rate Q _b , the lubricating frequency N is the lubricating frequency N _b , and the lubricating timing T _N is the lubricating timing at this lubricating frequency N _b . In this case, lubrication to the piston upper part 5a is performed in the order of the cycle number Y: "yes" → "no" → "yes" → "yes" → "no" → "yes" → "yes" → "no", . . .→“Yes” When the lubricating rate Q _N is the lubricating rate Q _a /2, the lubricating frequency N is the lubricating frequency N _a /2, and the lubricating timing T _N is the lubricating timing at this lubricating frequency N _a /2. In this case, lubrication to the piston upper part 5a is performed in the order of the cycle number Y: "yes" → "no" → "yes" → "no" → "yes" → "no" → "yes" → "no", It is performed in a pattern such as . When the lubricating rate Q _N is the lower limit lubricating rate Q _c , the lubricating frequency N is the lubricating frequency N _c and the lubricating timing T _N is the lubricating timing at this lubricating frequency N _c . In this case, the lubrication to the piston upper part 5a is performed in the order of the cycle number Y: "No" → "Yes" → "No" → "No" → "Yes" → "No" → "No" → "Yes", ..., → It is done in a pattern like "nothing".

FIG. 4 is a schematic diagram showing an example of a second data table used for lubrication control for the skirt portion according to the embodiment of the present invention. As shown in FIG. 4, the second data table 18b shows the correspondence relationship between the lubricating rate Q _M [g/kWh], the lubricating frequency M [times], and the lubricating timing T _M when lubricating oil is injected into the skirt portion 6b. is a data table showing

Specifically, in the second data table 18b shown in FIG. 4, the lubricating rate Q _M is registered to be a constant ratio R to the lubricating rate Q _N for the piston upper portion 5a. That is, the oil supply rate Q _M is expressed by multiplying the oil supply rate Q _N and the constant rate R (Q _N ×R). For example, as shown in FIG. 4, when the oil supply rate _QN for the piston upper portion 5a is the maximum oil supply rate _Qa , the oil supply rate _QM is the product of the maximum oil supply rate _Qa and the constant rate R (= Q _a ×R). In the present embodiment, this lubricating rate Q _M (=Q _a ×R) is a lubricating rate corresponding to the maximum lubricating rate Q _a for the piston upper portion 5a. As shown in FIG. 4, the corresponding relationship between these lubricating rates Q _M and Q _N is the same for lubricating rates Q _N other than the maximum lubricating rate Q _a . In addition, it is preferable that the constant ratio R described above is, for example, 10% or more and 15% or less.

The lubricating frequency M is a numerical value indicating the lubricating frequency (the frequency of lubricating the skirt portion 6b) at each of the plurality of lubricating rates registered as the lubricating rate Q _M for the skirt portion 6b. Each numerical value of the lubricating frequency M is equal to or less than the number of piston cycles in which the piston upper portion 5a is not lubricated within a certain cycle period. Specifically, each numerical value of the lubricating frequency M has an upper limit (Y _e −N) obtained by subtracting the lubricating frequency N for the piston upper portion 5a from the number of piston cycles (=Y _e ) included in a certain cycle period. is set as However, when the lubricating rate Q _M for the skirt portion 6b exceeds Q _b ×R, as shown in FIG. 4, the lubricating frequency M is zero (M=0). Of the lubricating frequencies M in the second data table 18b, the lubricating frequency _Ma is the lubricating frequency corresponding to the upper limit lubricating rate _Qb , and the lubricating frequency _Md is the lubricating frequency corresponding to the lubricating rate _Qa /2. , the lubricating frequency M _e is the lubricating frequency corresponding to the lower limit lubricating rate Q _c .

Further, in the second data table 18b shown in FIG. 4, the lubricating timing _TM is the timing of lubricating the skirt portion 6b. Specifically, as shown in FIG. 4, the lubricating timing _TM is represented by a combination of the cycle number Y of the piston cycle described above and the crank angle B corresponding to the skirt portion 6b. The cycle number Y at this lubricating timing T _M is the same cycle number as the lubricating timing T _N for the piston upper portion 5a shown in FIG. That is, the piston cycle at the lubricating timing T _M for the skirt portion 6b is synchronized with the piston cycle at the lubricating timing T _N for the piston upper portion 5a. The crank angle B corresponds to the lubrication timing for each piston cycle in which the skirt portion 6b is lubricated. That is, in the second data table 18b, "yes" and "no" indicate whether or not the skirt portion 6b is lubricated for each piston cycle. In the "yes" piston cycle, the skirt portion 6b is lubricated at the timing when the crank angle of the marine internal combustion engine becomes "B". In the "none" piston cycle, the skirt portion 6b is not lubricated. The number of "present" piston cycles included in the constant cycle period of the lubricating timing _TM is the frequency of lubricating the skirt portion 6b within the constant cycle period, and is represented by the lubricating frequency M described above.

As shown in FIG. 4, such lubricating timing T _M is associated with lubricating frequency M and lubricating rate Q _M (that is, Q _N ×R). It is set so as not to overlap with lubricating the skirt portion 6b. For example, when the lubricating rate Q _N is the maximum lubricating rate Q _a , the lubricating rate Q _M =Q _a ×R and the lubricating frequency M=0. In this case, at the lubricating timing T _M , lubrication to the skirt portion 6b is "absent" in all piston cycles of cycle numbers 1 to Y _e . When the lubricating rate Q _N is the upper limit lubricating rate Q _b , the lubricating rate Q _M =Q _b ×R, the lubricating frequency M is the lubricating frequency M _a , and the lubricating timing T _M is the lubricating frequency M _a . It is time to lubricate. In this case, the skirt portion 6b is lubricated in the order of cycle number Y: "No" → "Yes" → "No" → "No" → "Yes" → "No" → "No" → "Yes". . . , → "None" When the lubricating rate Q _N is the lubricating rate Q _a /2, the lubricating rate Q _M =(Q _a /2)×R, the lubricating frequency M is the lubricating frequency M _d , and the lubricating timing _TM is this lubricating It becomes the lubricating timing at the frequency _Md . In this case, the skirt portion 6b is lubricated in the order of the cycle number Y: "No" → "No" → "No" → "Yes" → "No" → "Yes" → "No" → "No". . . , → "yes". When the lubricating rate Q _N is the lower limit lubricating rate Q _c , the lubricating rate Q _M =Q _c ×R, the lubricating frequency M is the lubricating frequency M _e , and the lubricating timing T _M is the lubricating frequency M _e . It is time to lubricate. In this case, the skirt portion 6b is lubricated in the order of the cycle number Y: "No" → "No" → "No" → "No" → "No" → "No" → "Yes" → "No". . . , → "yes".

The lubricating timings T _N and T _M shown in FIGS. 3 and 4 are examples of lubricating timings for the piston upper portion 5a and the skirt portion 6b, respectively, and do not limit the present invention. The lubricating timings T _N and T _M are lubricating timings other than the patterns shown in FIGS. good too.

(Lubricating the upper part of the piston)
Next, the lubrication to the piston upper portion 5a will be described in detail. FIG. 5 is a schematic diagram showing an example of lubrication to the piston upper portion 5a according to the embodiment of the present invention. In this embodiment, the piston upper portion 5a is lubricated, for example, when the piston 5 is moving upward from the bottom dead center Cb side to the top dead center Ct side in the process of reciprocating inside the cylinder 1 .

Specifically, as shown in FIG. 5, the piston 5 moves up inside the cylinder liner 2 while the piston rings 7a to 7c are in sliding contact with the inner peripheral surface 2a of the cylinder liner 2. As shown in FIG. At this time, the piston 5 is raised toward the position of the lubricating port of the lubricating rod 11 provided in the cylinder liner 2 .

Here, at the timing when the crank angle of the marine internal combustion engine reaches crank angle A (hereinafter referred to as the first timing), the rising piston 5 is positioned at a predetermined portion of the piston upper portion 5a, for example, as shown in FIG. A position is reached in which the lower end of the crown portion 6a faces the lubricating port of the lubricating rod 11. As shown in FIG. As shown in FIG. 5, the lower end portion of the crown portion 6a is a portion adjacent to the upper end portion of the uppermost piston ring 7a. At this first timing, as shown in FIG. 5, the injection of the lubricating oil 30 to the piston upper portion 5a is started. At this time, the lubricating oil 30 is first discharged from the lubricating rod 11 to the lower end portion of the crown portion 6a.

After that, the piston 5 continues to rise inside the cylinder liner 2, and as shown in FIG. Reach the position to face. At the timing when the rising piston 5 reaches the position (hereinafter referred to as the second timing), the lubrication of the lubricating oil 30 to the piston upper portion 5a ends. That is, the lubricating oil 30 is continuously discharged from the lubricating rod 11 to the piston upper portion 5a during the period from the first timing to the second timing described above. This period is the same as the period from when the solenoid valve 13 shown in FIG. The lubricating oil 30 is applied to a region extending from the lower end of the crown portion 6a of the rising piston 5 to the lowest piston ring 7c.

The piston 5 to which the lubricating oil 30 is supplied in this manner continues to reciprocate inside the cylinder liner 2 while spreading the lubricating oil 30 by the piston rings 7a to 7c. As a result, an oil film of the lubricating oil 30 is formed between the inner peripheral surface 2 a of the cylinder liner 2 and the piston 5 .

(Lubricating the piston skirt)
Next, lubrication to the piston skirt (that is, the skirt portion 6b of the piston 5) will be described in detail. FIG. 6 is a schematic diagram showing an example of lubricating the piston skirt in the embodiment of the present invention. In the present embodiment, the skirt portion 6b is lubricated, for example, when the piston 5 moves downward from the top dead center Ct side to the bottom dead center Cb side in the process of reciprocating inside the cylinder 1 .

Specifically, as shown in FIG. 6, the piston 5 descends inside the cylinder liner 2 while the piston rings 7a to 7c are in sliding contact with the inner peripheral surface 2a of the cylinder liner 2. As shown in FIG. At this time, the piston 5 is lowered toward the position of the lubricating port of the lubricating rod 11 provided in the cylinder liner 2 .

Here, at the timing when the crank angle of the marine internal combustion engine reaches the crank angle B (hereinafter referred to as the third timing), the piston 5 that is descending moves to a predetermined portion of the skirt portion 6b, for example, as shown in FIG. A position is reached in which the lower end of the portion 6b faces the lubricating port of the lubricating rod 11. As shown in FIG. At this third timing, as shown in FIG. 6, the supply of lubricating oil 30 to the skirt portion 6b is started. At this time, the lubricating oil 30 is first discharged from the lubricating rod 11 to the lower end portion of the skirt portion 6b.

After that, the piston 5 continues to descend inside the cylinder liner 2, and reaches a position where the upper end of the skirt portion 6b faces the lubricating port of the lubricating rod 11, as shown in FIG. As shown in FIG. 6, the upper end of the skirt portion 6b is adjacent to the lower end of the lowermost piston ring 7c. At the timing when the descending piston 5 reaches the position (hereinafter referred to as the fourth timing), the supply of the lubricating oil 30 to the skirt portion 6b ends. That is, the lubricating oil 30 is continuously discharged from the lubricating rod 11 to the skirt portion 6b during the period from the third timing to the fourth timing described above. This period is the same as the period from when the solenoid valve 13 shown in FIG. 1 is driven to open until it is driven to close. The lubricating oil 30 is applied to a region from the lower end to the upper end of the skirt portion 6b of the piston 5 during the descent.

The piston 5 to which the lubricating oil 30 is supplied in this manner continues to reciprocate inside the cylinder liner 2 while spreading the lubricating oil 30 by the piston rings 7a to 7c. As a result, an oil film of the lubricating oil 30 is formed between the inner peripheral surface 2a of the cylinder liner 2 and the skirt portion 6b.

(Lubrication control)
Next, lubrication control by the cylinder lubrication system 10 according to the embodiment of the present invention will be described in detail. FIG. 7 is a flow chart showing an example of a processing flow of lubricating control by the cylinder lubricating system according to the embodiment of the present invention. The cylinder lubrication system 10 (see FIG. 1) controls the lubrication of lubricating oil to the piston 5 in the cylinder 1 by appropriately performing steps S101 to S116 shown in FIG.

Specifically, as shown in FIG. 7, the cylinder lubrication system 10 sets a reference lubrication rate Q _s in lubrication control (step S101). In step S101, the central control unit 17 sets the oil supply rate when the engine load is 100% as the standard oil supply rate _Qs .

For example, when the designated value of the reference lubricating rate is not input to the control device 16 from the operation device 15, the central control unit 17 refers to the first data table 18a and determines the plurality of values registered in the first data table 18a. The maximum lubricating rate _Qa of the lubricating rate _QN is set as the standard lubricating rate _Qs . Alternatively, if a specified value for the standard lubricating rate is input from the operating device 15 to the controller 16, the central control unit 17 sets the standard lubricating rate _Qs based on this input specified value. At this time, the central control unit 17 sets the oil supply rate closest to the specified value from among the plurality of oil supply rates _QN registered in the first data table 18a as the reference oil supply rate _Qs . For example, if there is an oil supply rate that is the same as the designated value among these plurality of oil supply rates Q _N , the central control unit 17 sets the oil supply rate that is the same as the designated value as the reference oil supply rate Q _S . If there is no lubricating rate equivalent to the specified value among these plurality of lubricating rates Q _N , the central control unit 17 selects the lubricating rate that has the smallest difference from the specified value among these plurality of lubricating rates Q _N as a reference. It is set as the lubricating rate Q _s .

After executing the process of step S101, the cylinder lubrication system 10 derives the lubrication rate Q of lubricating oil to be lubricated to the piston 5 in the cylinder 1 (step S102). In step S102, the central control unit 17 derives the oil supply rate Q according to the engine load of the marine internal combustion engine.

Specifically, when the operating mode of the marine internal combustion engine is the mean effective pressure proportional mode, the control device 16 detects the current engine speed of the marine internal combustion engine detected by the speed detector 22 and the load detector 23 Acquire the current engine load of the detected marine internal combustion engine. The central control unit 17 calculates the average effective pressure of the cylinder 1 based on the acquired engine speed and engine load. Next, the central control unit 17 obtains the ratio of the calculated average effective pressure to the average effective pressure when the engine load is 100%, and multiplies the obtained ratio by the reference lubricating rate _Qs . , to derive the oil supply rate Q corresponding to the current engine load. Alternatively, when the operating mode of the marine internal combustion engine is the output proportional mode, the control device 16 acquires the current engine load of the marine internal combustion engine detected by the load detector 23 . The central control unit 17 derives the oil filling rate Q according to the current engine load by performing processing such as multiplication of the obtained engine load and the standard oil feeding rate _Qs .

After executing the process of step S102, the cylinder lubrication system 10 determines the level of the derived lubrication rate Q (step S103). In step S103, the central control unit 17 compares the lubrication rate Q derived by the process of step S102 with the upper limit lubrication rate _Qb and the lower limit lubrication rate _Qc registered in the first data table 18a. Through this comparison processing, the central control unit 17 determines whether or not the lubricating rate Q exceeds the upper limit lubricating rate _Qb , and whether or not the lubricating rate Q is within the range of the lower limit lubricating rate Qc _or higher and the upper limit lubricating rate Qb _or lower. or whether or not the lubricating rate Q is lower than the lower limit lubricating rate _Qc .

When the lubricating rate Q exceeds the upper limit lubricating rate Q _b (step S103, Q>Q _b ), the control device 16 determines the lubricating frequency at the lubricating rate Q and the A timing is determined (step S104).

In step S104, the lubricating rate Q is equal to any one of the lubricating rates _QN registered in the first data table 18a that is greater than the upper limit lubricating rate Qb _and less than or equal to the maximum lubricating rate _Qa . The central control unit 17 selects the lubricating frequency and lubricating timing corresponding to the lubricating rate Q from among the lubricating frequency N and the lubricating timing T _N registered in the first data table 18a. Determined as lubricating frequency and lubricating timing. That is, the central control unit 17 determines the frequency of lubricating oil to the piston upper part 5a for each fixed cycle period, the piston cycle in which the lubricating oil is injected among a plurality of piston cycles included in the fixed cycle period, An object to be lubricated (piston upper portion 5a) for each piston cycle is determined. The central control unit 17 instructs the drive control unit 19 on the lubrication frequency and lubrication timing determined as described above.

After executing the processing of step S104, the cylinder lubricating system 10 controls the lubricating oil injection for the piston upper portion 5a (step S105). In step S105, the drive control unit 19 controls the opening/closing drive of the solenoid valve 13 so that the lubricator 12 injects lubricating oil at the lubrication frequency and lubrication timing instructed by the central control unit 17 in the process of step S104. .

Specifically, based on the lubricating frequency instructed by the central control unit 17, the drive control unit 19 grasps the lubricating frequency N for the piston upper part 5a for each fixed cycle period. Based on the lubricating timing instructed by the central control unit 17, the drive control unit 19 also controls the cycle number Y of the piston cycle with lubrication in which the piston upper part 5a is lubricated within a certain cycle period. Crank angle A at the time of lubrication is grasped. Further, the drive control unit 19 sequentially acquires the crank angles of the marine internal combustion engine detected by the angle detector 21 in chronological order. The drive control unit 19 controls the electromagnetic valve 13 to open at the timing when the obtained crank angle becomes the crank angle A in the piston cycle in which the piston upper part 5a is lubricated. After that, the drive control unit 19 controls the solenoid valve 13 so that the open state is maintained for a predetermined period and the solenoid valve 13 is driven to close. Based on the crank angle detected by the angle detector 21, the drive control unit 19 grasps one cycle of the piston cycle, and controls the opening/closing drive of the electromagnetic valve 13 as described above according to the cycle number Y of the piston cycle. Execute sequentially (in chronological order). The lubricating device 12 injects lubricating oil into the piston upper part 5a of the piston 5 rising in the cylinder 1 through the lubricating rod 11 or the like while the electromagnetic valve 13 is in the open state, as shown in FIG. .

After executing the processing of step S105, the cylinder lubricating system 10 determines whether or not the engine load of the marine internal combustion engine is constant (step S106). In step S106, the central control unit 17 determines that the engine load is not constant (has changed) when there is a change of a predetermined value or more between the engine loads sequentially obtained from the load detector 23 . Further, when the difference between the engine loads sequentially obtained from the load detector 23 is less than a predetermined value, the central control unit 17 determines that the engine load is constant.

When the engine load is constant in step S106 (step S106, Yes), the cylinder lubricating system 10 returns to step S105 and repeats the processing after step S105. On the other hand, when the engine load changes in step S106 (step S106, No), the cylinder lubricating system 10 returns to step S102 and repeats the processing after step S102.

On the other hand, in the process of step S103 described above, when the oil filling rate Q is within the range of the lower limit oil filling rate Qc _or more and the upper limit oil feeding rate _{Qb or} less (step S103, _Qc ≤ Q ≤ _Qb ), the control device 16 , the piston upper portion 5a and the skirt portion 6b of the piston 5, the lubricating frequency and the lubricating timing at the lubricating rate Q are determined (step S107).

In step S107, the lubricating rate Q is the same value as one of the lubricating rates _QN registered in the first data table 18a within the range of the lower limit lubricating rate _Qc or higher and the upper limit lubricating rate _{Qb or} lower. The central control unit 17 determines the lubricating frequency and lubricating timing corresponding to this lubricating rate Q as the lubricating frequency and lubricating timing of the lubricating oil to the piston upper portion 5a in the same manner as in step S104 described above.

In step S107, the central control unit 17 multiplies the lubricating rate Q and the fixed rate _R (lubricating rate Q× The lubricating frequency and lubricating timing corresponding to R) are determined as the lubricating oil frequency and lubricating timing for the skirt portion 6b. That is, the central control unit 17 controls each frequency of lubricating oil to be injected into each of the piston upper part 5a and the skirt part 6b for each fixed cycle period, and the lubricating oil injection frequency among a plurality of piston cycles included in the fixed cycle period. and the lubrication target (either the piston upper portion 5a or the skirt portion 6b) for each piston cycle. The central control unit 17 instructs the drive control unit 19 on the lubrication frequency and lubrication timing determined as described above.

After executing the processing of step S107, the cylinder lubricating system 10 determines whether or not to permit the lubricating oil to be injected into the skirt portion 6b (step S108). In the cylinder lubricating system 10, when the user operates the operation device 15 to input permission information to the control device 16, the lubricating oil is permitted to be injected into the skirt portion 6b. In step S108, when permission information is input from the operation device 15 to the control device 16, the central control unit 17 sets a permission flag based on the input permission information, and performs a process such as setting a permission flag so that the skirt portion 6b can be directed to the skirt portion 6b. Permission is given to the drive control unit 19 to supply lubricating oil. On the other hand, when permission information is not input from the operation device 15 to the control device 16, the central control portion 17 prohibits the drive control portion 19 from injecting lubricating oil into the skirt portion 6b.

In step S108, when lubricating oil is permitted to be injected into the skirt portion 6b (step S108, Yes), the cylinder lubricating system 10 controls lubricating oil injection for each of the piston upper portion 5a and the skirt portion 6b. (Step S109). In step S109, the drive control unit 19 controls the opening/closing drive of the electromagnetic valve 13 so that the lubricating oil is injected by the lubricator 12 at the lubricating frequency and the lubricating timing instructed by the central control unit 17 in the process of step S107. .

More specifically, the drive control unit 19 controls the piston upper part 5a, similarly to step S105 described above, with the lubrication frequency N for each fixed cycle period, the cycle number Y of the piston cycle with lubrication within the fixed cycle period, Crank angle A at the time of executing the lubrication is grasped. Further, based on the lubrication frequency instructed by the central control unit 17 for the skirt portion 6b, the drive control portion 19 grasps the lubrication frequency M to the skirt portion 6b for each fixed cycle period. Further, based on the lubricating timing instructed by the central control unit 17 for the skirt portion 6b, the drive control unit 19 controls the cycle number Y of the piston cycle with lubrication in which the skirt portion 6b is lubricated within a certain cycle period. and the crank angle B at the time of executing the lubrication. The drive control unit 19 synchronizes the piston cycle of the piston upper portion 5a within a fixed cycle period and the piston cycle of the skirt portion 6b within a fixed cycle period. That is, the cycle number Y of the piston cycle within the fixed cycle period is common to the piston upper portion 5a and the skirt portion 6b.

Further, the drive control unit 19 sequentially acquires the crank angles of the marine internal combustion engine detected by the angle detector 21 in chronological order. The drive control unit 19 controls the opening/closing drive of the electromagnetic valve 13 in the same manner as in step S105 described above, regarding the injection of lubricating oil into the piston upper portion 5a. In parallel with this, the drive control unit 19 controls the electromagnetic valve 13 so that it is driven to open at the timing when the acquired crank angle becomes the crank angle B in the piston cycle in which the skirt portion 6b is lubricated. After that, the drive control unit 19 controls the solenoid valve 13 so that the open state is maintained for a predetermined period and the solenoid valve 13 is driven to close. Based on the crank angle detected by the angle detector 21, the drive control unit 19 grasps one cycle of the piston cycle, and controls the opening/closing drive of the electromagnetic valve 13 as described above according to the cycle number Y of the piston cycle. Execute sequentially (in chronological order).

The lubricator 12, for example, as shown in FIG. Lubricating oil is applied to the piston upper portion 5a of the piston 5 which is rising in the cylinder 1. As shown in FIG. In addition, the lubricator 12 operates during a period in which the solenoid valve 13 is continuously open from the above-described third timing (timing of the crank angle B) to the fourth timing in a piston cycle different from the lubricating timing of the piston upper portion 5a. For example, as shown in FIG. 6, the lubricating oil is supplied to the skirt portion 6b of the piston 5 which is descending in the cylinder 1 through the lubricating rod 11 or the like.

On the other hand, in step S108 described above, if the lubricating oil is not permitted to be injected into the skirt portion 6b (step S108, No), the cylinder lubricating system 10 does not inject the lubricating oil into the skirt portion 6b, and the piston Lubrication of lubricating oil is controlled for the upper portion 5a (step S110). In step S110, the drive control unit 19 causes the lubricator 12 to supply lubricating oil at the lubrication frequency and lubrication timing for the piston upper portion 5a among the lubrication frequency and lubrication timing instructed by the central control unit 17 in the process of step S107. The opening/closing drive of the electromagnetic valve 13 is controlled so as to lubricate.

Specifically, the drive control unit 19 controls the opening/closing drive of the electromagnetic valve 13 so that the lubricating oil is supplied to the piston upper portion 5a, as in step S105 described above. Further, the drive control unit 19 does not control the opening/closing drive of the electromagnetic valve 13 even at the timing when the crank angle acquired from the angle detector 21 becomes the crank angle B. of lubricating oil is prohibited to the lubricator 12. During the period in which the solenoid valve 13 is continuously open from the above-mentioned first timing to the second timing, the lubricator 12 is ascending in the cylinder 1 through the lubricating rod 11 and the like as shown in FIG. A lubricating oil is applied to the piston upper portion 5a of the piston 5. As shown in FIG. On the other hand, the lubricator 12 does not inject lubricating oil into the skirt portion 6b.

After executing the process of step S109 or step S110, the cylinder lubrication system 10 determines whether or not the engine load of the marine internal combustion engine is constant (step S111). In step S111, the central control unit 17 determines whether or not the engine load is constant, as in step S106 described above.

When the engine load is constant in step S111 (step S111, Yes), the cylinder lubricating system 10 returns to step S108 and repeats the processing after step S108. On the other hand, when the engine load changes in step S111 (step S111, No), the cylinder lubricating system 10 returns to step S102 and repeats the processing after step S102.

Here, when the cylinder lubricating system 10 repeatedly executes each process of steps S108 to S111, there is a possibility that the lubricating oil injection to the skirt portion 6b is once prohibited and then permitted. In this case, lubricating oil may be added to the skirt portion 6b from the middle of the piston cycle within the constant cycle period in which the lubricating oil to the piston upper portion 5a is started. In this embodiment, as described above, the piston cycle within the fixed cycle period for the piston upper portion 5a and the piston cycle within the fixed cycle period for the skirt portion 6b are synchronized. Therefore, even if lubricating oil is added to the skirt portion 6b from an intermediate piston cycle as described above, lubricating oil is injected to the piston upper portion 5a and to the skirt portion 6b within one piston cycle. It is possible to avoid a situation that overlaps with lubrication of oil.

On the other hand, in the process of step S103 described above, when the oil filling rate Q is lower than the lower limit oil filling rate Q _c (step S103, Q<Q _c ), the control device 16 controls the piston upper portion 5a and the skirt portion 6b of the piston 5 to: The lubricating frequency and the lubricating timing are determined not for the lubricating rate Q but for the lower limit lubricating rate _Qc (step S112).

In step S112, the lower limit lubricating rate _Qc is the minimum lubricating rate among the lubricating rates _QN registered in the first data table 18a. The central control unit 17 determines the lubricating frequency and lubricating timing corresponding to the lower limit lubricating rate _Qc as the lubricating frequency and lubricating timing of the lubricating oil to the upper piston portion 5a in the same manner as in step S107 described above.

In step S112, the central control unit 17 multiplies the lower limit lubricating rate _Qc and the constant rate _R (lubricating rate Q _c ×R) is determined as the lubricating frequency and lubricating timing of the lubricating oil to the skirt portion 6b in the same manner as in step S107 described above. The central control unit 17 instructs the drive control unit 19 on the lubrication frequency and lubrication timing determined as described above.

After executing the processing of step S112, the cylinder lubricating system 10 determines whether or not to permit the lubricating oil to be injected into the skirt portion 6b (step S113). In step S113, similar to step S108 described above, the central control unit 17 permits the lubricating oil to be injected into the skirt portion 6b based on the permission information input from the operation device 15 to the control device 16. If the information is not entered, the supply of lubricating oil to the skirt portion 6b is prohibited.

In step S113, when lubricating oil is permitted to be injected into the skirt portion 6b (step S113, Yes), the cylinder lubricating system 10 controls lubricating oil injection for each of the piston upper portion 5a and the skirt portion 6b. (Step S114). In step S114, the drive control unit 19 controls the solenoid valve 13 for each of the piston upper portion 5a and the skirt portion 6b in the same manner as in step S109 described above, except that the lubricating rate Q is replaced with the lower limit lubricating rate _Qc . Controls open/close drive.

On the other hand, in step S113 described above, if the lubricating oil is not permitted to be injected into the skirt portion 6b (step S113, No), the cylinder lubricating system 10 does not inject the lubricating oil into the skirt portion 6b, and the piston Lubrication of lubricating oil is controlled for the upper portion 5a (step S115). In step S115, the drive control unit 19 controls the opening/closing drive of the solenoid valve 13 for the piston upper portion 5a in the same manner as in step S110 described above, except that the lubricating rate Q is replaced with the lower limit lubricating rate _Qc .

After executing the process of step S114 or step S115, the cylinder lubricating system 10 determines whether or not the engine load of the marine internal combustion engine is constant (step S116). In step S116, the central control unit 17 determines whether or not the engine load is constant, as in step S106 described above.

When the engine load is constant in step S116 (step S116, Yes), the cylinder lubricating system 10 returns to step S113 and repeats the processing after step S113. On the other hand, when the engine load changes in step S116 (step S116, No), the cylinder lubricating system 10 returns to step S102 and repeats the processing after step S102.

It should be noted that even when the processes of steps S113 to S116 described above are repeatedly executed, the piston cycle within the fixed cycle period for the piston upper portion 5a and the piston cycle for the skirt portion 6b within the fixed cycle period are synchronized. Therefore, it is possible to avoid a situation in which lubricating oil is applied to the piston upper portion 5a and lubricating oil is applied to the skirt portion 6b in one piston cycle.

Further, when the engine load has changed, in step S102 described above, the oil filling rate Q is derived according to the engine load after the change. After that, in each of steps S104, S107, and S112 described above, the lubricating frequency and lubricating timing for piston 5 are switched to the lubricating frequency and lubricating timing at lubricating rate Q after the engine load has changed. In each of steps S105, S109, S110, S114, and S115 described above, lubrication of lubricating oil to piston 5 is controlled with the lubrication frequency and lubrication timing switched according to the change in engine load as described above. At this time, even if the lubricating control had progressed to the piston cycle in the middle of the constant cycle period before the engine load changed, the lubricating oil is injected into the piston 5 at the lubricating frequency and lubricating timing after the switching. Control is re-started from the first (cycle number Y=1) piston cycle in the period.

In the cylinder lubricating system 10, each time a specified value of the reference lubricating rate is newly input from the operating device 15, the control device 16 performs the processing of step S101 described above, and then the processing of step S102 and thereafter. may be repeated as appropriate.

As described above, in the cylinder lubrication system 10 according to the embodiment of the present invention, the control device 16 derives the lubricating oil injection rate Q for the piston 5 according to the engine load of the marine internal combustion engine, and the derived lubrication The lubricating oil frequency and lubricating timing for the upper half portion (piston upper portion 5a) and the skirt portion 6b of the piston 5 at the rate Q are determined. The opening/closing drive of the solenoid valve 13 is controlled so as to lubricate the lubricating oil to the . Based on the drive control by the controller 16, the lubricating oil is accumulated in the lubricator 12 when the electromagnetic valve 13 is closed. When the solenoid valve 13 is open, the lubricating device 12 lubricates the piston 5 reciprocating inside the cylinder 1 of the marine internal combustion engine with lubricating oil through the lubricating rod 11 provided in the cylinder 1 .

Therefore, the frequency and timing of lubricating oil injection into each of the piston upper portion 5a and the skirt portion 6b can be controlled according to the in-cylinder pressure applied to the crown portion 6a of the piston 5 . As a result, the lubricating oil required to ensure the slidability of the piston 5 with respect to the inner peripheral surface 2a of the cylinder 1 can be injected between the inner peripheral surface 2a of the cylinder 1 and the piston 5, and the pressure in the cylinder increases. When the piston 5 is difficult to tilt inside the cylinder 1, lubricating oil is excessively supplied to the skirt portion 6b, and when the pressure in the cylinder decreases and the piston 5 tends to tilt inside the cylinder 1. It is possible to avoid a situation in which lubricating oil is insufficiently supplied to the skirt portion 6b. As a result, the amount of lubricating oil supplied to each of the piston upper portion 5a and the skirt portion 6b can be suppressed, so that the lubricating oil can be efficiently supplied to the piston 5 reciprocating inside the cylinder 1. .

Further, in the cylinder lubricating system 10 according to the embodiment of the present invention, the control device 16 makes the lubricating oil injection rate to the skirt portion 6b a constant ratio with respect to the lubricating oil injection rate to the piston upper portion 5a. Thus, the frequency and timing of lubricating oil injection to the piston upper portion 5a and the frequency and timing of lubricating oil injection to the skirt portion 6b are determined. Therefore, the lubricating oil can be supplied to the piston upper portion 5a and the skirt portion 6b in a well-balanced manner.

Further, in the cylinder lubricating system 10 according to the embodiment of the present invention, the control device 16 sets the reference lubricating rate when the engine load is 100% based on the specified value that is changeably input by the operating device 15. Based on the set reference lubricating rate, the lubricating oil feeding rate Q corresponding to the engine load is derived. Therefore, it is possible to easily change the reference lubricating rate by changing the specified value that is input according to the user's input operation. As a result, the reference lubrication rate can be reduced according to the operating time (operating time) of the marine internal combustion engine, the state of the piston ring provided on the piston 5, the inner peripheral surface 2a of the cylinder 1, and the like. As a result, it is possible to promote a reduction in the cost required for ship operation.

Further, in the cylinder lubricating system 10 according to the embodiment of the present invention, the control device 16 permits lubricating oil to be injected into the skirt portion 6b of the piston 5 based on the permission information input by the operating device 15. . Therefore, the user can select whether or not to permit the injection of the lubricating oil to the skirt portion 6b. can be done.

In addition, in the cylinder lubricating system 10 according to the embodiment of the present invention, the lubricator 12 is injected into the piston upper portion 5a of the piston 5 that is ascending or the skirt portion 6b of the piston 5 that is descending based on the crank angle of the marine internal combustion engine. The opening/closing drive of the solenoid valve 13 is controlled so that the lubricating oil is injected. Therefore, the lubricating oil injected into the piston upper part 5a can spread between the inner peripheral surface 2a of the cylinder 1 and at least the piston upper part 5a as the piston 5 reciprocates to form an oil film. Further, the lubricating oil applied to the skirt portion 6b can be spread between the inner peripheral surface 2a of the cylinder 1 and at least the skirt portion 6b as the piston 5 reciprocates to form an oil film. As a result, an oil film of lubricating oil can be efficiently formed between the inner peripheral surface 2a of the cylinder 1 and the piston 5 to ensure the slidability of the piston 5 with respect to the inner peripheral surface 2a.

In addition, although the case where the eight lubricating rods 11 were provided in one cylinder 1 was illustrated in embodiment mentioned above, this invention is not limited to this. In the present invention, the number of lubricating rods 11 provided in one cylinder 1 is not particularly limited, and may be two or more (plurality), for example.

In the above-described embodiment, lubricating oil is injected into the piston upper portion 5a when the piston 5 is ascending, and lubricating oil is injected into the skirt portion 6b while the piston 5 is descending. The invention is not limited to this. For example, lubricating oil may be applied to the piston upper portion 5a while the piston 5 is descending. At this time, the injection of the lubricating oil may be started from the position of the lowest piston ring 7c in the piston upper portion 5a. Alternatively, the lubricating oil may be applied to the skirt portion 6b while the piston 5 is ascending. At this time, the lubricating oil may start to be injected from the upper end portion of the skirt portion 6b (the portion adjacent to the lowermost piston ring 7c).

In addition, in the above-described embodiment, when permission information is input to the control device 16, lubrication of the skirt portion 6b is permitted, but the present invention is not limited to this. For example, the operation device 15 inputs prohibition information for prohibiting lubricating oil to the skirt portion 6b to the control device 16 according to the user's input operation, and the control device 16 controls the input prohibition information. , the lubricating oil supply to the skirt portion 6b may be prohibited.

In the above-described embodiment, the single operating device 15 functions as a first input unit for inputting the specified value of the reference lubricating rate and as a second input unit for inputting permission information for lubricating the skirt portion 6b. However, the present invention is not limited to this. For example, the cylinder lubricating system 10 may include the first input section and the second input section described above as separate input sections (operating devices).

Further, in the above-described embodiment, three piston rings are illustrated as an example of the plurality of piston rings provided on the outer peripheral portion of the piston body, but the present invention is not limited to this. For example, two or more piston rings may be provided on the outer peripheral portion of the piston body so as to line up in the reciprocating direction of the piston body.

Further, in the above-described embodiment, the case where the angle detector 21, the rotation speed detector 22 and the load detector 23 are provided in the marine internal combustion engine was illustrated, but the present invention is not limited to this. . For example, the angle detector 21, the rotation speed detector 22, and the load detector 23 may each be one configuration example of the cylinder lubricating system 10 according to the embodiment of the present invention. Similarly, the temperature detector 24 and the pressure detector 25 may also be one configuration example of the cylinder lubrication system 10 .

Moreover, the present invention is not limited by the above-described embodiments. The present invention also includes those configured by appropriately combining the respective constituent elements described above. In addition, other embodiments, examples, operation techniques, etc. made by those skilled in the art based on the above-described embodiments are all included in the scope of the present invention.

1 Cylinder 2 Cylinder Liner 2a Inner Peripheral Surface 3 Cylinder Cover 4 Combustion Chamber 5 Piston 5a Piston Upper Part 6 Piston Body 6a Crown 6b Skirt 6c Intermediate Part 7a, 7b, 7c Piston Ring 8 Piston Rod 9 Exhaust Valve 10 Cylinder Lubrication System REFERENCE SIGNS LIST 11 lubrication rod 12 lubrication device 13 solenoid valve 14 lubrication unit 15 operating device 16 control device 17 central control unit 18a first data table 18b second data table 19 drive control unit 21 angle detector 22 rotation speed detector 23 load detector 24 Temperature detector 25 Pressure detector 30 Lubricating oil Ct Top dead center Cb Bottom dead center

Claims (7)

a lubricator for lubricating a piston reciprocating inside a cylinder of a marine internal combustion engine with lubricating oil through a lubricating rod provided in the cylinder;
a solenoid valve that accumulates the lubricating oil in the lubricator in the closed state and causes the lubricator to inject the lubricating oil into the piston in the open state;
Deriving the lubrication rate of the lubricating oil according to the load of the marine internal combustion engine, and determining the lubrication frequency and lubrication timing of the lubricating oil to each of the piston upper portion and the skirt portion of the piston at the derived lubrication rate. a control device for controlling the opening/closing drive of the solenoid valve so that the lubricator injects the lubricating oil at the determined lubricating frequency and lubricating timing;
A cylinder lubrication system, comprising: The control device supplies the lubricating oil to the upper portion of the piston so that the rate of lubricating oil to the skirt portion is constant with respect to the rate of lubricating oil to the upper portion of the piston. Determining the lubrication frequency and lubrication timing, and the lubrication frequency and lubrication timing of the lubricating oil to the skirt;
The cylinder lubricating system according to claim 1, characterized in that: The control device sets the lubricating oil injection rate when the load of the marine internal combustion engine is 100% as a reference oil injection rate, and uses the set reference oil injection rate as a reference, depending on the load of the marine internal combustion engine. Deriving the lubrication rate of the lubricating oil,
3. The cylinder lubricating system according to claim 1 or 2, characterized in that: an input unit for inputting a specified value for specifying the reference lubricating rate to be changeable to the control device;
The control device sets the reference lubricating rate based on the input specified value.
4. The cylinder lubricating system according to claim 3, characterized in that: an input unit for inputting permission information for permitting injection of the lubricating oil into the skirt portion to the control device;
The control device permits injection of the lubricating oil into the skirt portion based on the input permission information.
The cylinder lubricating system according to any one of claims 1 to 4, characterized in that: The control device determines whether or not to inject the lubricating oil into the piston for each cycle included in a fixed cycle period in which one reciprocating motion of the piston constitutes one cycle, and determines whether or not to inject the lubricating oil into the piston. determining whether to lubricate the portion or the skirt portion;
The cylinder lubricating system according to any one of claims 1 to 5, characterized in that: Based on the crank angle of the marine internal combustion engine, the control device causes the lubricator to inject the lubricating oil into the piston upper portion of the piston that is ascending or the skirt portion of the piston that is descending. , controlling the opening and closing drive of the solenoid valve;
The cylinder lubricating system according to any one of claims 1 to 6, characterized in that:

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