JP4395474B2 - Internal combustion engine equipped with scavenging control device - Google Patents

Description

  The present invention is a two-cycle internal combustion engine that is applied to a two-cycle large-sized diesel engine, in which a plurality of scavenging holes for supplying scavenging gas into the cylinder are formed in the lower part of the cylinder liner along the circumferential direction. When the scavenging port and the scavenging hole communicate with each other, scavenging can be supplied into the cylinder, and when the scavenging port and the scavenging hole of the cylinder liner are shut off, the supply of scavenging into the cylinder is stopped. The present invention relates to an internal combustion engine provided with a scavenging air control device configured as described above.

  A two-cycle large diesel engine usually employs a uniflow scavenging system, and before the bottom dead center of the piston, a plurality of scavenging holes are formed in the lower part of the cylinder liner along the circumferential direction. The scavenging air is supplied from the scavenging holes into the cylinder, and the residual combustion gas in the cylinder is pushed out through an exhaust valve provided in the cylinder cover.

  In such a uniflow scavenging two-cycle large diesel engine, the cylinder liner is fitted to either the inside or the outside of the cylinder liner so as to be movable in the circumferential direction, and the scavenging hole of the cylinder liner is opened and closed. Japanese Patent Application Laid-Open No. 2004-340120 proposes an annular scavenging control valve that supplies and shuts off scavenging air.

  In the diesel engine provided with the scavenging control device provided in Patent Document 1, the inside of a cylinder liner in which a plurality of scavenging holes for supplying scavenging gas into the cylinder are formed in the lower part along the circumferential direction. The cylinder liner is movably fitted in the circumferential direction of the cylinder liner and communicated with or cut off from the cylinder liner scavenging holes by relative movement in the circumferential direction with respect to the cylinder liner. A scavenging control valve drive device that has a plurality of scavenging ports that open and close in the circumferential direction, has an annular scavenging control valve that supplies and shuts off scavenging in the cylinder, and the supply and discharge of hydraulic fluid can be switched by an electromagnetic valve By moving the scavenging control valve in the circumferential direction, the scavenging port of the scavenging control valve and the cylinder liner scavenging hole are communicated and blocked.

JP 2004-340120 A

However, the conventional technique disclosed in Patent Document 1 (Japanese Patent Laid-Open No. 2004-340120) has the following problems to be solved.
That is, FIG. 10 is an enlarged sectional view in the vicinity of a scavenging port of a scavenging control valve of a diesel engine equipped with the scavenging control device according to the prior art. In such a diesel engine with a scavenging control valve, 100 is a cylinder liner having a scavenging hole (not shown), 1 is a scavenging control valve having a scavenging port 4, 103 is a piston, and 106 is a plurality of fittings inserted on the outer periphery of the piston 103. It is a piston ring of a stage (4 stages in this example).

In such a diesel engine with a scavenging control valve, the scavenging port 4 of the scavenging control valve 1 and the scavenging holes (not shown) of the cylinder liner are one stage, and the port width in the height direction of the scavenging port 4 in order to increase the scavenging port area. As a result, the height direction port width of the scavenging port 4 is longer than the length between the uppermost piston ring and the lowermost piston ring.
For this reason, in this prior art, when the piston 103 descends and the uppermost piston ring 106 starts to open the scavenging port 4, the combustion in the piston ring upper gap 103a is indicated by the arrow T in FIG. Since the gas blows through the scavenging port 4 and reaches the skirt side of the lower part of the piston, the engine performance is deteriorated and it is easy to induce seizure of the piston ring due to adhesion of the combustion gas residue to the sliding surface 100b.

  Further, in such a conventional diesel engine with a scavenging control valve, the scavenging control valve is moved in the circumferential direction by a scavenging control valve driving device in which the supply and discharge of hydraulic oil is switched by an electromagnetic valve, and the scavenging port of the scavenging control valve And the cylinder liner scavenging holes are communicated and cut off, so that the consumption of hydraulic oil for driving the scavenging control valve drive device increases and energy loss due to the compression work of the hydraulic oil increases. I also have the problem.

  In view of the problems of the prior art, the present invention avoids the combustion gas in the piston ring upper gap from being blown through the scavenging port, thereby lowering the engine performance and burning the piston ring due to adhesion of combustion residue to the piston ring sliding surface. In addition to preventing the occurrence of sticking, etc., the accumulation of the combustion residue from the upper clearance of the piston ring when the scavenging hole is closed and the occurrence of seizure of the piston ring due to this are prevented, and the scavenging control valve is driven. An object of the present invention is to provide an internal combustion engine with a scavenging control device that reduces the amount of working fluid consumed to reduce the energy loss due to the compression work of the working fluid.

The present invention achieves such an object. In an internal combustion engine in which a plurality of scavenging holes for supplying scavenging gas into a cylinder are formed in the lower part of the cylinder liner along the circumferential direction of the cylinder liner, An annular shape that is fitted to a fitting surface formed on either the inner side or the outer side so as to be movable in the circumferential direction of the cylinder liner, opens and closes the scavenging hole, and supplies and blocks the scavenging gas into the cylinder. The scavenging control valve has a plurality of scavenging ports in the circumferential direction and a plurality of stages in the axial direction that are communicated with or cut off from the scavenging holes of the cylinder liner by the movement of the scavenging control valve in the circumferential direction. together provided, Inner distance between the top piston ring and bottom piston ring which is fitted the per stage of the scavenging port height direction port widths (L1), the piston (L2 Smaller than (L1 <L2) formed, and the plurality of stages in the height direction port width H1 of the uppermost scavenge out of the scavenging port smaller than the height direction port width H2 of the second stage and subsequent scavenging port (H1 <H2) It is formed .

  Further, the present invention provides an annular ring having a plurality of scavenging ports for opening and closing the scavenging holes in the circumferential direction by communicating with or shutting off the scavenging holes of the cylinder liner to supply and block the scavenging in the cylinder. Preferably, the scavenging control valve and a fluid driving means provided inside the cylinder liner and moving the scavenging control valve in the circumferential direction by the pressure of the working fluid are installed above the scavenging control valve. .

According to the present invention, the fluid drive means includes a drive side actuator and a return side actuator that are supplied and discharged by switching a solenoid valve in a circumferential direction of the scavenging control valve, and the drive side actuator and the return side actuator. It is preferable that the scavenging control valve is operated in the driving direction and the return direction by supplying and discharging the working fluid in the following manner and configured as follows.
(1) The operating area of the driving actuator that operates the scavenging control valve in the driving direction is configured to be larger than the operating area of the return actuator that operates the scavenging control valve in the returning direction.
(2) The pressure of the working fluid of the drive side actuator is made larger than the pressure of the working fluid supplied to the return side actuator.

Furthermore, in this invention, the following configuration is preferable.
(1) When the solenoid valve is not in operation, the scavenging port of the scavenging control valve and the scavenging hole of the cylinder liner are held in communication with a working fluid passage connecting the solenoid valve and the drive side actuator. A scavenging hole opening means for supplying the working fluid is provided.
(2) Provided with a spring that biases the scavenging port of the scavenging control valve and the scavenging hole of the cylinder liner in a communicating state when the solenoid valve is inoperative.

According to the present invention, while the scavenging port of the scavenging control valve is provided in a plurality of stages in the axial direction to keep the scavenging passage area large, the height direction port width L1 per stage of the scavenging port is set to be the same as that of the uppermost piston ring. By forming a distance smaller than the inner distance L2 between the lower piston ring (L1 <L2) (Claim 1), one of the plurality of piston rings is always applied to the scavenging port to perform gas sealing of the scavenging port. Therefore, it is possible to shut off the gas that blows through the piston ring upper gap through the scavenging port to the lower part (skirt part) of the piston when the piston descends.
Therefore, according to such an invention, the scavenging ports are provided in a plurality of stages in the axial direction to increase the scavenging passage area and maintain high scavenging efficiency to maintain good engine performance, while passing through the scavenging port from the piston ring upper gap. The combustion of the combustion gas reaching the piston skirt side and the occurrence of seizure of the piston ring due to the adhesion of the combustion residue to the piston ring sliding surface can be prevented.

Also, when the scavenging port of the scavenging control valve and the scavenging hole of the cylinder liner are shut off, when the piston descends and the uppermost piston ring begins to open the scavenging port, the uppermost scavenging port Although the in-cylinder pressure higher than the scavenging port acts and the combustion gas slightly leaks, in the present invention, the height direction port width H1 of the uppermost scavenging port is larger than the height direction port width H2 of the second and subsequent scavenging ports. Ri by the also be small (H1 <H2) formation, it is possible to reduce the gas leakage from the top scavenging port.

  Further, according to the present invention, the fluid driving means is installed on the upper part of the scavenging control valve (Claim 2), and the scavenging port forming part in the lower part of the scavenging control valve is made a thin free end, so that the piston It is possible to prevent buckling deformation of the scavenging control valve when descending due to internal pressure.

Further, in the scavenging control valve, it is essential to increase the engine performance to increase the valve opening speed for communicating the scavenging port and the scavenging hole of the cylinder liner and to quickly exchange the exhaust gas and fresh air. However, even if the valve closing speed for shutting off the scavenging port and the scavenging hole of the cylinder liner is decreased, there is no influence on the engine performance.
On the other hand, the working fluid for driving the scavenging control valve consumes only the pressure receiving area x stroke of the driving side or return side actuator, and the compression work of the working hydraulic pressure x hydraulic oil consumption is required. The smaller the pressure receiving area, the more the working fluid consumption and the compression work of the working fluid can be reduced, and the lower the working oil pressure, the more the compression work can be reduced.

  However, according to the present invention, the operating area (pressure receiving area) of the driving actuator that operates the scavenging control valve in the driving direction is larger than the operating area (pressure receiving area) of the return actuator that operates the scavenging control valve in the returning direction. Since it is configured (Claim 3), the operating area (pressure receiving area) of the drive side actuator that operates the valve opening side of the scavenging port and the scavenging hole of the cylinder liner is kept large and the engine performance is maintained at the target performance. By reducing the operating area (pressure receiving area) of the return side actuator that operates on the valve closing side, the working fluid consumption and the compression work of the working fluid can be reduced. Thereby, the efficiency of the whole engine can be raised.

  According to the present invention, since the pressure of the working fluid of the drive side actuator is configured to be larger than the pressure of the working fluid supplied to the return side actuator (Claim 4), the operation of the drive side actuator that performs the valve opening side operation is performed. While keeping the hydraulic pressure high to keep the engine performance at the target performance, the compression work of the working fluid can be reduced by reducing the hydraulic pressure of the return side actuator that operates the valve closing side. Thereby, the efficiency of the whole engine can be raised.

According to the present invention, the scavenging port of the scavenging control valve is connected to the working fluid passage that connects the solenoid valve, the drive side actuator, and the return side actuator when the solenoid valve that switches the working fluid to the fluid drive means is inoperative. And a scavenging hole opening means for supplying a working fluid so as to keep the scavenging hole of the cylinder liner in communication with each other (Claim 5 ), or the scavenging port of the scavenging control valve and the scavenging of the cylinder liner when the solenoid valve is not operated. By providing a spring that biases the air holes so as to keep them in communication with each other (Claim 6), even if the solenoid valve becomes inoperable due to a failure or the like, the scavenging port opening means and the cylinder liner are Since the scavenging holes are communicated with each other, normal operation can be continued without being affected by the malfunction of the solenoid valve.

  Hereinafter, the present invention will be described in detail with reference to the embodiments shown in the drawings. However, the dimensions, materials, shapes, relative arrangements, and the like of the components described in this embodiment are not intended to limit the scope of the present invention only to specific examples unless otherwise specified. Only.

Figure 1 is a cross sectional view taken along the cylinder center showing the scavenging ports of the scavenging port and the scavenging control valve in two-stroke large diesel engine according to the Reference Examples and Examples of the present invention, FIG. 2 of Figure 1 in the Reference Examples and Examples It is sectional drawing which follows the BB line.
1 and 2, reference numeral 100 denotes a cylinder liner composed of a liner upper part 100c and a liner outer cylinder part 100d, and 103 denotes a piston that reciprocally slides on the inner surface of the cylinder liner 100 and a scavenging control valve 1 to be described later via a piston ring 106. is there. Reference numeral 105 denotes a scavenging chamber.
101 is a scavenging hole, and a plurality of holes are drilled in the lower part of the cylinder liner 100 at equal intervals in the circumferential direction. In the example of FIG. 2, the scavenging holes 101 are inclined scavenging holes inclined in the circumferential direction, but are not limited to the inclined scavenging holes.
Reference numeral 1 denotes an annular scavenging control valve made of a wear-resistant material, which is fitted to a fitting surface 100a formed on the inner periphery of the cylinder liner 100 so as to be relatively rotatable with the cylinder liner 100, and an inner peripheral surface 100b is formed. It is a sliding surface (piston ring sliding surface) of the piston ring 106.

As shown in FIG. 2, the scavenging control valve 1 has the same number of scavenging ports 4 as the scavenging holes 101 in the circumferential direction. As shown in FIG. 2, the scavenging port 4 is located between the scavenging holes 101 of the cylinder liner 100 when fully closed, and is located in the same phase as the scavenging holes 101 when fully opened, and is completely in communication with the scavenging holes 101. It is supposed to be.
The present invention relates to an improvement in a scavenging control valve and related members in an internal combustion engine with a scavenging control valve configured as described above.

Reference example

FIG. 3 is a cross-sectional view of an essential part along the center of the cylinder in the vicinity of the scavenging port portion of the scavenging control valve in a reference example (including the configuration of the example, hereinafter referred to as reference example and example) as a premise of the present invention . FIG. 4 is an explanatory view of an operation in a reference example and an embodiment , and is a main part sectional view corresponding to FIG. 3.
In this reference example , in the scavenging control valve 1, a plurality of scavenging ports 4 are provided in the circumferential direction and a plurality of stages in the axial direction (three stages in this example), and the height of the scavenging port 4 per stage is provided. The direction port width L1 is formed to be smaller than the inner distance L2 between the uppermost piston ring 106a and the lowermost piston ring 106d inserted into the piston 103 (L1 <L2). Reference numerals 106b and 106c denote a second stage piston ring and a third stage piston ring.
Therefore, in the reference example and the embodiment , the lower edge of the uppermost piston ring 106a is the first step when the piston 103 indicated by the arrow S is lowered, as shown in FIG. When it reaches the upper edge of the scavenging port 4, the upper edge of the lowermost piston ring 106d is above the lower edge of the first stage scavenging port 4, and the piston ring upper gap 103a and the lower part of the piston 103 (skirt portion) ) And the scavenging chamber 105.
Even in the subsequent positions of the piston 103, the communication between the piston ring upper gap 103a, the lower portion (skirt portion) of the piston 103 and the scavenging chamber 105 is always cut off.

According to the reference example and the embodiment, the scavenging port 4 of the scavenging control valve 1 is provided with a plurality of stages (three stages in this example) in the axial direction to keep the scavenging passage area large, of the height direction port widths L1, by reducing (L1 <L2) than the inner dimensions distance L2 between the top piston ring 106a and bottom piston ring 106d, or a plurality of stages of piston rings 106 Since the gas is sealed at the scavenging port 4 at all times, when the piston 103 is lowered, the piston ring upper gap 103a passes through the scavenging port 4 to the lower part (skirt part) of the piston 103 and the scavenging chamber 105. The combustion gas that blows through can be shut off.
As a result, a plurality of scavenging ports 4 are provided in the axial direction to increase the scavenging passage area, maintain high scavenging efficiency, and maintain good engine performance, while maintaining good engine performance and passing through the scavenging port 4 from the piston ring upper gap 103a. The occurrence of seizure of the piston ring 106 (106a to 106d) due to the blow-through of the combustion gas reaching the side and the accompanying combustion gas residue adhering to the piston ring sliding surface 100b can be prevented.

5A and 5B show a first embodiment of the present invention, in which FIG. 5A is a cross-sectional view taken along line BB in FIG. 1, and FIG. 5B is a cross-sectional view taken along line CC in FIG.
In the first embodiment, among the scavenging ports 4a and 4b provided in a plurality of stages in the axial direction of the scavenging control valve 1, the height direction port width H1 of the uppermost scavenging port 4a is set to the scavenging port 4b in the second and subsequent stages. Is smaller than the port width H2 in the height direction (H1 <H2). In addition, 103 is a piston and 200 is a cylinder center.

According to the first embodiment , in addition to the configurations of the reference example and the embodiment , the height direction port width H1 of the uppermost scavenging port 4a is made larger than the height direction port width H2 of the second and subsequent scavenging ports 4b. By forming it small (H1 <H2), when the piston 103 descends and the uppermost piston ring 106a starts to open the scavenging port 4a, the inner cylinder pressure applied to the uppermost scavenging port 4a and the liner outer cylinder portion 100d The amount of combustion gas leaking from the scavenging valve 1 can be reduced.

6 is a cross-sectional view taken along line AA of FIG. 1 showing a second embodiment of the present invention, and FIG. 7 is an enlarged cross-sectional view of the main part of FIG. 6 in the second embodiment.
6-7, 3a is a drive side actuator, 100e is a drive side hydraulic oil inlet / outlet, 3b is a return side actuator, and 100f is a return side hydraulic oil inlet / outlet. The drive side hydraulic oil inlet / outlet 100e and the return side hydraulic oil inlet / outlet 100f are shown. Is connected to a solenoid valve (not shown), and hydraulic oil is supplied and discharged by switching the solenoid valve.

That is, as shown in FIGS. 6 and 7, the hydraulic oil from the solenoid valve is supplied to the drive side actuator 3a through the drive side hydraulic oil inlet / outlet 100e, and the hydraulic oil in the return side actuator 3b is returned to the return side hydraulic oil. When the oil is extracted from the inlet / outlet 100f to the oil discharge side, the scavenging control valve 1 is rotated in the direction of the arrow M in the figure by the driving side actuator 3a, and the scavenging hole 101 (see FIG. 1) of the scavenging port 4 and the liner outer cylinder portion 100d. And the scavenging control valve 1 is opened.
Further, the hydraulic oil from the solenoid valve is supplied to the return side actuator 3b through the return side hydraulic oil inlet / outlet 100f, and the hydraulic oil in the driving side actuator 3a is drawn from the driving side hydraulic oil inlet / outlet 100e to the oil discharge side. Then, the scavenging control valve 1 is rotated in the direction opposite to the arrow M in the figure by the return side actuator 3b, and the communication between the scavenging port 4 and the scavenging hole 101 (see FIG. 1) of the liner outer cylinder portion 100d is cut off. Thus, the scavenging control valve 1 is closed.

In the second embodiment, the drive-side actuator 3a and the return-side actuator 3b configured as described above are used, the operation area (pressure receiving area) A1 of the drive-side actuator 3a is set, and the operation area of the previous return-side actuator 3b is set. (Pressure receiving area) It is configured to be larger than A2 (A1> A2).
Here, in the scavenging control valve 1, the scavenging port 4 and the scavenging hole 101 of the cylinder liner 100 (liner outer cylinder portion 100d) communicate with each other at a high valve opening speed so that the exhaust gas and fresh air can be exchanged quickly. Although it is essential to improve the engine performance, there is no influence on the engine performance even if the valve closing speed for shutting off the scavenging port 4 and the scavenging hole 101 of the cylinder liner is reduced.
On the other hand, since the hydraulic oil for driving the scavenging control valve 1 is consumed by the pressure receiving area (operating area) × stroke of the driving side actuator 3a or the return side actuator 3b, the smaller the pressure receiving area of the actuator operates. Oil consumption and hydraulic oil compression work can be reduced.
In the second embodiment, the pressure of the working fluid supplied to the return side actuator 3b is smaller than the pressure of the working fluid of the drive side actuator 3a (the pressure of the working fluid of the drive side actuator 3a is set to the return side). The pressure of the working fluid of the actuator 3b is larger).

Therefore, according to the second embodiment, the operating area (pressure receiving area) A1 of the drive side actuator 3a for operating the scavenging control valve 1 in the valve opening direction (driving direction) is set to the closing direction (return direction) of the scavenging control valve 1. ) Is larger than the operating area (pressure receiving area) A2 of the return side actuator 3b (A1> A2), so that the driving side actuator that operates the valve opening side of the scavenging port 1 and the scavenging hole 101 of the cylinder liner is provided. The operation area (pressure receiving area) A1 of 3a is kept large to keep the engine performance at the target performance, while the operation area (pressure receiving area) A2 of the return side actuator 3b that operates on the valve closing side is reduced to operate Oil consumption and hydraulic oil compression work can be reduced. Thereby, the efficiency of the whole engine can be raised.
Further, since the hydraulic pressure requires compression work equal to the hydraulic pressure × hydraulic oil consumption, the compression work can be reduced when the hydraulic pressure is lower.
However in the second embodiment that written back side the pressure of the hydraulic fluid supplied to the actuator 3b, since it is configured smaller than the pressure of the working fluid of the drive side actuator 3a, the drive side actuator for the actuation of the valve-opening While maintaining the engine hydraulic pressure at a high level to maintain the engine performance at the target performance, the hydraulic pressure of the return side actuator that operates on the valve closing side is reduced to reduce the compression work of the working fluid. Thereby, the efficiency of the whole engine can be raised.

FIG. 8 is a cross-sectional view corresponding to the line AA of FIG. 1 showing a third embodiment of the present invention.
In the third embodiment, an electromagnetic valve that performs switching control of the drive side actuator 3a and the return side actuator 3b of the scavenging control valve 1 is used as the scavenging port 4 except when the electromagnetic valve is operated. The scavenging hole 101 of the cylinder liner 100 is provided so as to be kept in communication. 100e is a drive side hydraulic oil inlet / outlet, and 100f is a return side hydraulic oil inlet / outlet.
According to the third embodiment, the scavenging port 4 of the scavenging control valve 1 and the scavenging hole 101 of the cylinder liner 100 are kept in communication even when the electromagnetic valve 5 becomes inoperative due to a failure or the like. Thus, normal operation can be continued without being affected by the malfunction of the solenoid valve.

FIG. 9 is a cross-sectional view corresponding to the line AA of FIG. 1 showing a fourth embodiment of the present invention.
In the fourth embodiment, an electromagnetic valve 51 for supplying hydraulic oil to the drive side actuator 3a when the solenoid valve is not operated is provided, and a spring 11 is provided instead of the return side actuator 3b, and the drive side actuator 3a is set as a spring. The position is set in balance with 11 elasticity.
According to the fourth embodiment, even when the solenoid valve becomes inoperative due to a failure or the like, the scavenging port 4 of the scavenging control valve 1 and the scavenging hole 101 of the cylinder liner 100 are communicated by the spring 11. Can be held.

In the fifth embodiment of the present invention, the upper part of the scavenging control valve 1 is configured as a drive unit 100f in FIGS. 1 and 6 to 7, and the drive unit 100f includes the drive side actuator 3a and the return side actuator 3b. Fluid drive means is installed.
According to the fifth embodiment, the fluid driving means is installed in the driving part 100f formed on the upper part of the scavenging control valve 1, preferably thicker than the part where the scavenging port 4 is formed. While increasing the rigidity of the drive unit 100f to be installed, the scavenging port 4 forming part at the lower part of the scavenging control valve 1 is made a thin free end, so that the scavenging control valve when the piston 103 is lowered by receiving the in-cylinder pressure. 1 buckling deformation can be prevented.

  According to the present invention, the engine gas is prevented from being blown into the scavenging port of the combustion gas in the upper clearance of the piston ring, the engine performance is deteriorated, and the piston ring is seized due to the adhesion of the combustion gas residue to the piston ring sliding surface. To prevent accumulation of combustion residue from the upper clearance of the piston ring when the scavenging hole is closed, and seizure of the sliding surface of the piston ring due to this, and to drive the scavenging control valve It is possible to provide an internal combustion engine with a scavenging control device that reduces the consumption of the working fluid and reduces energy loss due to the compression work of the working fluid.

It is sectional drawing in alignment with the cylinder center which shows the scavenging hole and scavenging port of the scavenging control valve in the 2-cycle large sized diesel engine which concerns on the reference example and Example of this invention. It is sectional drawing which follows the BB line of FIG. 1 in the said reference example and an Example. It is principal part sectional drawing along the cylinder center of the scavenging port part vicinity of the scavenging control valve in the reference example and Example of this invention. FIG. 4 is an explanatory diagram of operations in the reference example and the embodiment, and is a cross-sectional view of a main part corresponding to FIG. 3. 1A and 1B show a first embodiment of the present invention, in which FIG. 1A is a cross-sectional view taken along line BB in FIG. 1, and FIG. 2B is a cross-sectional view taken along line CC in FIG. It is sectional drawing which follows the AA line of FIG. 1 which shows 2nd Example of this invention. FIG. 7 is an enlarged cross-sectional view of a main part of FIG. 6 in the second embodiment. FIG. 6 is a cross-sectional view corresponding to the line AA in FIG. 1 showing a third embodiment of the present invention. FIG. 6 is a cross-sectional view corresponding to the line AA in FIG. 1 showing a fourth embodiment of the present invention. It is an expanded sectional view of the scavenging port vicinity of the scavenging control valve of the diesel engine provided with the scavenging control valve device concerning a prior art.

DESCRIPTION OF SYMBOLS 100 Cylinder liner 100a Fitting surface 100b Piston ring sliding surface 100d Liner outer cylinder part 100f Drive part 101 Scavenging hole 103 Piston 103a Piston ring upper clearance 106a, 106b, 106c, 106d Piston ring 1 Scavenge control valve 3a Drive side actuator 3b Return Side actuator 4 Scavenging port 11 Spring

Claims (6)

In an internal combustion engine in which a plurality of scavenging holes for supplying scavenging gas into the cylinder are formed in the lower part of the cylinder liner along the circumferential direction of the cylinder liner, the scavenging hole is formed on either the inside or the outside of the cylinder liner. The scavenging control valve has an annular scavenging control valve that is fitted to a fitting surface so as to be movable in the circumferential direction of the cylinder liner, opens and closes the scavenging hole, and supplies and shuts off scavenging in the cylinder. Are provided with a plurality of scavenging ports in the circumferential direction and in a plurality of stages in the axial direction, each of which is connected to or cut off from the scavenging holes of the cylinder liner by movement in the circumferential direction. a height direction port widths (L1), Inner distance between the top piston ring and bottom piston ring which is fitted to the piston (L2) smaller than (L1 <L2) is formed, One the plurality of stages smaller than the height direction port the width H2 in the height direction port the width H1 of the two-stage and subsequent scavenging port of the uppermost scavenge out of the scavenging port (H1 <H2) scavenging, characterized in that formed was An internal combustion engine equipped with a control valve device.   An annular scavenging control valve that has a plurality of scavenging ports in the circumferential direction to open and close the scavenging holes by communicating with or shutting off the scavenging holes of the cylinder liner; A fluid drive means provided inside the cylinder liner and above the scavenging control valve for moving the scavenging control valve in the circumferential direction by the pressure of a working fluid. An internal combustion engine comprising the scavenging control valve device according to 1.   The fluid drive means is provided with a drive side actuator and a return side actuator that are supplied and discharged by switching of an electromagnetic valve in a circumferential direction of the scavenging control valve, and the working fluid is supplied to the drive side actuator and the return side actuator. By supplying and discharging, the scavenging control valve is operated in the driving direction and the return direction, and the operating area of the driving side actuator that operates the scavenging control valve in the driving direction is operated in the return direction. The internal combustion engine provided with the scavenging control device according to claim 2, wherein the operating area of the return side actuator is larger.   The fluid drive means is provided with a drive side actuator and a return side actuator that are supplied and discharged by switching of an electromagnetic valve in a circumferential direction of the scavenging control valve, and the working fluid is supplied to the drive side actuator and the return side actuator. By supplying and discharging, the scavenging control valve is operated in the driving direction and the return direction, and the pressure of the working fluid of the driving actuator that operates the scavenging control valve in the driving direction is set in the return direction of the scavenging control valve. The internal combustion engine provided with the scavenging control valve device according to claim 2, wherein the pressure of the working fluid of the return side actuator to be operated is larger than the pressure of the working fluid.   When the solenoid valve is not in operation, the working fluid is configured to keep the scavenging port of the scavenging control valve and the scavenging hole of the cylinder liner in communication with the working fluid passage connecting the solenoid valve and the driving actuator. An internal combustion engine equipped with a scavenging control valve device according to claim 3, further comprising scavenging hole opening means for supplying gas.   4. A scavenging control system according to claim 3, further comprising a spring that urges the scavenging port of the scavenging control valve and the scavenging hole of the cylinder liner to be in communication with each other when the solenoid valve is not operating. An internal combustion engine provided with a valve device.

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