JP2011001948A - Piston engine with part for covering bottom surface of cap portion of poppet valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To increase the compression ratio of an engine which has a poppet valve provided to a combustion chamber portion expanded to the outside of a main cylinder, and to reduce the temperature of an exhaust poppet valve.SOLUTION: A valve cover 7 has a tubular side surface and an upper surface 8. A compression ring 9 is provided to either the tubular side surface or the inner wall of a sub cylinder 4. A means is provided that causes the bottom surface 3 of a poppet valve 2 and the upper surface 8 of the valve cover 7 to make close contact with each other. Most of the space within the combustion chamber facing the bottom surface 3 is occupied by the upper part of the valve cover 7 when the poppet valve 2 becomes closed. When the poppet valve 2 becomes lifted, the valve cover 7 moves together with the poppet valve 2. The combination of overhead valves 25A, 25B and the poppet valve 2 includes at least a pair of an intake valve and an exhaust valve, and the total number of the overhead valve 25A, 25B and the poppet valve 2 is three or more.

Description

   The present invention relates to a piston type engine having a part that covers a bottom surface of an umbrella portion of a valve. This component, when the combustion chamber is extended to the outside of the main cylinder, occupy the bottom space of the combustion chamber facing the mushroom valve which is located outside the main cylinder.

During high-speed rotation, the amount of intake resistance and exhaust resistance of the 4-cycle engine increases.
The lift amount of the intake cam of the engine is extremely smaller at the initial stage of opening the intake valve than the lift amount after the middle of the valve opening period. When the engine rotates at high speed, the initial time of the valve opening period is shortened. As a result, the inflow amount of intake air is limited. As a result, in the initial stage when the intake valve is opened, the pressure in the cylinder is lower than the pressure on the back side of the piston.
In this state, the piston continues to descend against the direction in which pressure is applied to the piston. This increases the amount of negative work. For this reason, the amount of loss due to intake resistance increases and torque decreases.
FIG. 14 shows the performance of the engine described in page 90 of the magazine “Internal Combustion Engine”, November 1995 No. 434, published by Sankaidou. Referring to FIG. 14, in the rotational speed range that is faster than the maximum torque values L1 and L2, the torque of the four-cycle engine is lower than that at the peak of the torque curve L1 and L2.
The lift amount of the exhaust cam of the 4-cycle engine is extremely smaller in the initial period of the valve opening period from when the exhaust valve is opened to the bottom dead center of the exhaust stroke than the lift amount after the middle period of the valve opening period. As a result, the cylinder pressure at the bottom dead center increases during high-speed rotation. As a result, the amount of loss due to exhaust resistance increases during the exhaust stroke immediately after the bottom dead center.
FIG. 15 shows a side valve type engine disclosed in Patent Document 1. The main combustion chamber shown by the engine number 54 is extended outside the cylinder. In Patent Document 1, the combustion chamber is compactly formed by narrowing the interval between the intake valve and the exhaust valve.
However, the volume of the main combustion chamber increases only in the space between the wall surface on which the side valve is installed and the facing surface. The volume of this space increases as the lift amount of the side valve increases. For this reason, the side valve type combustion chamber cannot have a high compression ratio. As a result, the side valve type engine described in Patent Document 3 is shown in FIG. A combustion chamber space exists between one end of the guide hole of FIG. 17 facing the combustion chamber and the valve seat for the intake valve. In FIG. 17, the combustion chamber is expanded to the outside of the variable volume member 17 when the direction of the variable volume member is viewed from the cylinder central axis. This expanded portion increases the combustion chamber volume.
The guide hole is indicated by the number 18. The intake valve is indicated by numeral 13. The variable volume member is indicated by numeral 17. The combustion chamber is indicated by the number 9.
In the side valve type internal combustion engine of Patent Document 3, a pair of intake valves and exhaust valves are installed on the side of the outer periphery of the cylinder. Therefore, the sum of the areas of a pair of intake valves and exhaust valves of the side valve type internal combustion engine of Patent Document 3 is smaller than an engine in which four valves are provided on the combustion chamber wall surface facing the upper surface of the piston.
In the side valve type internal combustion engine of Patent Document 3, the portion of the variable volume member that protrudes into the combustion chamber is heated by the combustion gas while the intake valve is closed, and the temperature rises.

Piston engines burn intermittently. For this reason, in the piston engine, the inner wall surface of the combustion chamber is cooled by the intake air. For this reason, in the spark ignition engine, a flame extinguishing layer (quenching zone) of the air-fuel mixture is formed along the inner wall surface of the combustion chamber. This flame extinguishing layer prevents high heat from flowing into the inner wall of the combustion chamber.
When the exhaust soot valve is opened, the bottom surface of the umbrella portion of the exhaust soot valve and the top surface of the umbrella portion facing the gas passage are both in contact with the combustion gas. Then, the temperature of the exhaust soot valve increases. When the piston is heavily loaded, it is difficult to form a flame-extinguishing layer of the air-fuel mixture along the bottom surface of the umbrella portion of the exhaust valve. For this reason, the air-fuel mixture layer along the bottom surface self-ignites. When the amount of the air-fuel mixture that self-ignites increases, the extinguishing layer facing the inner wall surface of the combustion chamber other than the bottom surface is destroyed. That is, knocking occurs.
FIG. 16 shows the engine of Patent Document 2.
When the sliding valve of the third aspect described in Patent Document 2 is used as an exhaust valve, the upper and lower surfaces of the first compression ring of the sliding valve are exposed to combustion gas at the start of the exhaust stroke. The first compression ring is indicated by the number 8. For this reason, said 1st compression ring is heated more than the combustion temperature of lubricating oil with combustion gas. The first compression ring is seized. The engine of Patent Document 2 forms a secondary cylinder outside the main cylinder.

If the stroke length of the piston is made longer than the diameter of the piston, the combustion gas conversion efficiency is improved, but the intake efficiency during high-speed rotation is reduced. The reduction in intake efficiency reduces the torque during high-speed rotation. On the other hand, if the stroke length of the piston is made shorter than the diameter of the piston, the intake efficiency at high speed rotation is improved, but the conversion efficiency of the combustion gas is lowered.
For this reason, the conventional spark ignition type engine cannot achieve both a long stroke of the piston and an increase in torque during high-speed rotation.
JP 2000-282814 (P2000-282814A) Japanese Patent Application No. 2008-120801, Patent Registration No. 4230529 JP 2001-355470 A

The first purpose is to increase the compression ratio of a piston-type engine with a valve on the wall of the combustion chamber extended outside the main cylinder.
The second purpose is to cool the exhaust valve.
The third purpose is to improve the fuel efficiency of piston-type engines.
The configuration of the piston engine of the first aspect of the present invention will be described below.
The piston type engine of the present invention has a cylinder head, a cylinder block, a main cylinder, a piston, a sub cylinder, an overhead valve, a soot valve, and a part that covers the bottom surface of the umbrella portion of the soot valve.
The piston reciprocates within the main cylinder. The combustion chamber is formed between the piston and the cylinder head. The combustion chamber is extended outside the main cylinder. The inner wall surface of the combustion chamber includes a first portion and a second portion. The first part is the part of the inner wall facing the upper surface of the piston. The second part is the part of the inner wall that extends outside the main cylinder. The sub-cylinder is installed outside the main cylinder.
A soot valve is installed in the second part of the inner wall surface. The soot valve has a second drive device for driving the shaft portion of the soot valve. When the soot valve opens, gas passes between the soot valve and a second valve seat for the soot valve.
The part reciprocates in the secondary cylinder, and the part has a cylindrical side surface.
The soot valve is located between the second valve seat and the component.
Means are provided for bringing the second valve seat, the soot valve and the component into close contact with each other. One of the means is a combination of an integral formation of the soot valve and the component and a device for moving the component toward the second valve seat, and the component is used as the second valve seat. The installation of a pushing device is one of the above means.
A third spring installed in contact with the component, a pneumatic device installed in contact with the component, a hydraulic device installed in contact with the component, and a second installed in contact with the shaft portion of the valve One of the springs is the device that moves the component toward the second valve seat.
One of a third spring installed in contact with the component, a pneumatic device installed in contact with the component, and a hydraulic device installed in contact with the component includes the component as the second valve seat. It is the device that pushes toward.
By the second driving device and the means, the valve and the parts are driven integrally.
A compression ring is installed at a position sandwiched between the inner wall of the sub-cylinder and the cylindrical side surface of the component.
The component is positioned in contact with the bottom surface of the valve.
The overhead valve is installed on the first portion of the inner wall surface. The overhead valve has a first spring and a drive device. When the overhead valve opens, the gas passes between the overhead valve and a first valve seat for the overhead valve. The gas is one of intake air flowing into the combustion chamber and combustion gas flowing out of the combustion chamber.
The sum of the overhead valve and the soot valve includes at least one pair of an intake valve and an exhaust valve.
The sum of the number of overhead valves and the number of sputum valves is three or more.

The configuration of the second aspect of the present invention will be described below only with respect to the differences from the first aspect.
One end of the sub-cylinder is installed at a position adjacent to the second valve seat.
When the central axis of the sub-cylinder is viewed from a portion of the central axis of the main cylinder located in the combustion chamber, a part of the sub-cylinder is formed so as to face a part of the semicircular surface on the back side that cannot be seen.
The invisible half-side surface is the half-side surface of the cylindrical side surface adjacent to the valve.
No space for the combustion chamber is created outside the part of the sub-cylinder facing a part of the semicircular surface on the back side.
An opening of the secondary cylinder is provided on the secondary cylinder.
A first gas passage is installed between the second valve seat and the external space of the engine. A second gas passage that connects the main cylinder inner space and the first gas passage at a short distance while the soot valve is open is installed, and the opening is formed in the second gas passage. included.
The opening faces the half surface on the front side of the cylindrical side surface that can be seen from the portion where the central axis of the main cylinder is located in the combustion chamber.
Compared with the engine shown in Patent Document 3, the piston-type engine according to the second aspect reduces the area of the portion of the cylindrical side surface of the valve cover 7 where the heat of the combustion gas is applied, and the amount of heat loss of the engine decreases. Therefore, in the second embodiment, the third object is achieved.

The configuration of the third aspect of the present invention will be described below only with respect to the differences from the first aspect.
The length of the stroke of the piston of the engine of the first aspect and the second aspect is not set smaller than the diameter of the piston.
The piston-type engine of the third aspect improves combustion gas conversion efficiency as compared with an engine having a short stroke. It also improves the reduction in intake efficiency of high-speed rotation of long stroke engines. As a result, improvement in conversion efficiency and increase in torque at high speed can be achieved at the same time. Therefore, the third object is achieved in the third embodiment.
The piston engine of the three aspects of the present invention can be a spark ignition engine or a compression ignition engine, and the spark ignition engine can be two-cycle or four-cycle. If the engine of the present invention is a spark ignition type, the spark plug can be installed at any position on the wall surface of the combustion chamber.
In the engine of the three modes, the volume of the combustion chamber is reduced by the volume in which the upper part of the part projects into the combustion chamber space of the soot that is in contact with the soot valve that is closed when the part is not present. Therefore, the combustion chamber of the engine can have a high compression ratio. Therefore, the first purpose can be achieved.
Moreover, the sum area of the intake and exhaust valves of the engine of the three modes is increased as compared with an engine in which an overhead valve is provided only inside the main cylinder. Therefore, the amount of intake / exhaust resistance during high-speed rotation is reduced. Therefore, the output of the engine of the present invention can be increased.

A first embodiment will be described.
The first embodiment corresponds to the first aspect.
The piston type engine shown in FIGS. 1 and 2 has a cylinder head 5, a cylinder block 6, a main cylinder 1, a piston 26, a sub cylinder 4, overhead valves 25 </ b> A and 25 </ b> B, and a soot valve 2.
The piston 26 reciprocates in the main cylinder 1. The combustion chamber 27 is formed between the cylinder head 5 and the piston 26. The combustion chamber 27 is further expanded outside the main cylinder 1. The inner wall surface of the combustion chamber 27 includes a first portion and a second portion. The first part is the part of the inner wall facing the upper surface of the piston 26. The second part is the part of the inner wall that extends outside the main cylinder 1. The combustion chamber 27 can be expanded on both the right side outside the main cylinder 1 and the left side outside the main cylinder 1.
The sub cylinder 4 is installed in a cylinder block 6 outside the main cylinder 1.
Overhead valves 25 </ b> A and 25 </ b> B are installed in the first portion facing the upper surface of the piston 26. When the overhead valve 25 is opened, gas passes between the overhead valves 25A, 25B and the valve seat for the overhead valves 25A, 25B.
The overhead valves 25A and 25B have springs 29A and 29B. The overhead valves 25A and 25B have cams 28A and 28B as a first drive device for lifting the overhead valves 25A and 25B.
If the overhead valve 25A is selected as the intake valve and the overhead valve 25B is selected as the exhaust valve, during the intake stroke of the piston 26, the overhead valve 25A is opened by the cam 28A, and during the exhaust stroke of the piston 26, Valve 25B is opened by cam 28B.
The cam 28A for the overhead valve 25A and the cam 28B for the overhead valve 25B can be replaced by an electromagnetic device or a hydraulic device.
The soot valve 2 is installed in the second part extended outside the main cylinder 1. A plurality of gutter valves 2 may be installed in the second part. The bottom surface 3 of the valve 2 is the bottom surface of the umbrella part of the valve 2. A surface that is in close contact with the second valve seat 16 for the soot valve 2 when the soot valve 2 is closed is provided on the outer periphery of the upper surface of the umbrella portion of the soot valve 2. The soot valve 2 has a cam 30 in contact with the soot valve 2.
When the soot valve 2 is opened, intake or exhaust gas passes between the soot valve 2 and the second valve seat 16. That is, the soot valve 2 can be used as an intake soot valve or an exhaust soot valve.
When the soot valve 2 is used as an intake valve, the soot valve 2 is opened by the cam 30 during the intake stroke of the piston 26.
When the soot valve 2 is used as an exhaust valve, the soot valve 2 is opened by the cam 30 during the exhaust stroke of the piston 26.
The second drive unit that lifts the soot valve 2 includes a cam 30.
The cam 30 for the soot valve 2 can be replaced with an electromagnetic device or a hydraulic device.

Three installation examples of the intake valve and the exhaust valve will be described. Three installation examples relate to the overhead valves 25A and 25B and the sputum valve 2.
What is shown in the three installation examples is not shown in Patent Document 3.
In the three installation examples, the sum of the number of overhead valves and the number of sputum valves is three or more.
In the first example, a plurality of exhaust soot valves are installed in the second part, and the soot valves installed in the second part are limited to exhaust exhaust valves only. This element is not shown in Patent Document 3. At least one intake overhead valve is installed in the first portion.
Therefore, in the first example, the number and area of exhaust soot valves installed in the second portion can be increased as compared with the engines of Patent Document 1 and Patent Document 3.
When the exhaust soot valve is opened, the bottom surface 3 is covered with the upper surface 8 of the valve cover 7 described later, and the bottom surface 3 of the exhaust soot valve does not come into contact with the combustion gas. Then, the temperature of the exhaust soot valve does not become higher than that of the exhaust soot valve of Patent Document 1. Only the exhaust valve installed in the second part can be cooled. For this reason, the engine can achieve part of the second purpose.
The upper and lower surfaces of the compression ring 9 are not exposed to the combustion gas. Therefore, the temperature of the compression ring 9 does not become higher than when the sliding valve of the third aspect described in Patent Document 2 is used as an exhaust valve.
In the first example, the amount of burned gas passing through one exhaust soot valve installed in the second portion is reduced as compared with the exhaust soot valve of Patent Document 3, and the maximum temperature of the plurality of exhaust soot valves is increased. descend. For this reason, the knocking resistance of the first example is improved as compared with Patent Document 3.

A second example will be described.
A plurality of intake soot valves are installed in the second portion, and the soot valves installed in the second portion are limited to intake suction valves only. This element is not shown in Patent Document 3. At least one exhaust overhead valve is installed in the first part. Therefore, in the second example, the number and area of the intake valve can be increased as compared with the engines of Patent Document 1 and Patent Document 3.

A third example will be described with reference to FIG.
One or more arbitrary number of overhead valves are installed in the first part of the inner wall surface of the combustion chamber 27, and all the overhead valves provided in the first part are intake soot valves 33. An exhaust soot valve 34 is provided in a second portion that extends outside the main cylinder 1. For the same reason as the explanation of the temperature of the exhaust soot valve in the first example, the temperature rise of the exhaust soot valve 34 can be limited. The exhaust soot valve 34 does not decrease the filling rate of the intake air. For this reason, this engine can completely achieve the second purpose. The temperature of the intake soot valve 33 does not increase.
According to this setting, there is no portion on the wall surface of the combustion chamber that is hotter than the exhaust soot valve described in the prior art column. Therefore, when the piston is heavily loaded, a flame extinguishing layer of the air-fuel mixture is formed along all the wall surfaces of the combustion chamber.
As a result, the resistance to knocking of the spark ignition engine is improved as compared with the engines of Patent Document 1 and Patent Document 3. Then, the compression ratio of the engine can be increased, and the thermal efficiency of the engine is improved. For this reason, this engine can achieve the third purpose.
A piston engine can be operated if it has a pair of intake and exhaust valves. Therefore, if at least one set of intake valve and exhaust valve is included in the sum of the overhead valve and the soot valve 2, in the first embodiment, the valves other than the set of intake valve and exhaust valve are the intake valve and the exhaust valve. Operation is possible regardless of which of the valves is selected.
The sum of the number of overhead valves and the number of sputum valves shall be three or more.
It has been explained that there are two overhead valves, 25A and 25B. However, if the sum of the number of overhead valves and the number of sputum valves is three or more, the number of overhead valves is any number greater than or equal to one. I can do things. Unlike the above three examples, the intake valve or exhaust valve settings can be changed if the sum of the number of overhead valves and the number of soot valves is three or more.

The piston engine of the first embodiment has a valve cover 7.
The valve cover 7 reciprocates in the sub cylinder 4. The valve cover 7 is a part that covers the bottom surface 3 of the valve 2. The valve cover 7 is a component whose upper part protrudes into the internal space of the combustion chamber 27.
The valve cover 7 has a cylindrical side surface, an upper surface, and a back surface. The lower part of the cylindrical side surface faces the inner wall surface of the sub cylinder 4.
The valve cover 7 and the soot valve 2 are driven by a cam 30 that lifts the soot valve 2. The cam 30 is a second drive unit.
The extension of the central axis of the shaft portion of the soot valve 2 and the central axis of the sub cylinder 4 are set to be coincident or approximately parallel. Therefore, when the soot valve 2 is lifted by the cam 30, the valve cover 7 moves together with the soot valve 2, and the lower part of the valve cover 7 moves in the sub-cylinder 4. Therefore, the cam 30 for the soot valve 2 also functions as a drive device for lifting the valve cover 7.
A space is formed between the valve seat 16 of the soot valve 2 and the upper end 10 of the sub cylinder 4. The upper end 10 faces the space in the combustion chamber 27.
A ring groove for the compression ring 9 is provided on the cylindrical side surface of the valve cover 7. The compression ring 9 is installed in this ring groove. This element is not shown in Patent Document 3.

When the soot valve 2 is closed, the compression ring 9 is sandwiched between the inner wall of the sub cylinder 4 and the ring groove. Since the compression ring 9 is sandwiched between the inner wall of the sub-cylinder 4 and the cylindrical side surface of the valve cover 7 when the soot valve 2 is closed, it is located between the valve cover 7 and the inner wall of the sub-cylinder 4. The combustion chamber 27 is sealed by the compression ring 9 so that the combustion gas does not flow through the gap from the space in the combustion chamber 27 to the space where the valve cover 7 in the sub cylinder 4 does not exist.
A spring 12 for the valve cover 7 is installed in contact with the back surface of the valve cover 7 in order to bring the upper surface 8 of the valve cover 7 into close contact with the bottom surface 3 of the valve valve 2. The spring 12 presses the valve cover 7 against the bottom surface of the valve 2. For this reason, the valve cover 7 and the valve 2 are driven integrally by the cam 30 and the spring 12.
The spring 12 is one of the means for bringing the second valve seat, the valve 2 and the valve cover 7 into close contact.
The spring 12 is a device that pushes the valve cover 7 toward the second valve seat 16.
The spring 12 has the same function as a valve spring that can be installed in contact with the valve 2. In the embodiment shown in FIG. 1, the valve spring in contact with the gutter valve 2 is not installed. For this reason, the installation of the spring 12 in contact with the valve 2 can be omitted by the installation of the spring 12 for the valve cover 7. That is, the installation of the spring that is installed in contact with the shaft portion of the valve 2 is not essential. Of course, the spring installed in contact with the shaft portion of the valve 2 can be added.

While the piston is in the combustion stroke, the combustion gas flows into the ring groove through the gap between the cylindrical side surface of the valve cover 7 and the inner wall of the sub cylinder 4. This inflowing combustion gas flows in one direction. Then, a force in the direction of compressing the spring 12 is applied to the compression ring 9. Then, the combustion gas pushes the valve cover 7. Therefore, the strength of the spring 12 needs to exceed the combustion gas pressure applied to the compression ring 9.
The valve cover 7 is not driven when the gutter valve 2 is closed. Therefore, the valve cover 7 does not move when the piston is in the combustion stroke. Therefore, seizure of the valve cover 7 is unlikely to occur.

In FIG. 1, the state in which the upper surface 8 of the valve cover 7 and the bottom surface 3 of the valve 2 are in close contact with each other is displayed as a solid line drawn at the boundary between the valve cover 7 and the valve 2. In FIG. 1, two lead lines are drawn from a solid line indicating a state in which both are in close contact. The two lead lines are the lead line for 8 and the lead line for 3. The solid line represents the upper surface 8 of the valve cover 7 and the bottom surface 3 of the valve 2. For this reason, two lead lines are drawn in opposite directions.
When the upper surface 8 of the valve cover 7 and the bottom surface 3 of the soot valve 2 are in close contact, no combustion gas enters between the valve cover 7 and the bottom surface 3 of the soot valve 2. The size of the upper surface 8 of the valve cover 7 and the size of the bottom surface 3 of the soot valve 2 are preferably equal. In this case, no combustion gas pressure acts on the upper surface 8 of the valve cover 7. When the upper surface 8 of the valve cover 7 is larger than the bottom surface 3 of the soot valve 2, the combustion gas pressure acts on the upper surface 8 of the valve cover 7.
The soot valve 2 is closed during the combustion stroke of the piston 26. A valve cover 7 is located in contact with the bottom surface 3 of the valve 2. As a result, most of the space in the combustion chamber expanded outside the main cylinder 1 of the soot that is in contact with the bottom face 3 of the soot valve 2 that is closed when the valve cover 7 is not present is actually in the valve cover 7. The upper part occupies. As a result, the volume of the combustion chamber 27 is reduced by the volume in which the upper portion of the valve cover 7 protrudes into the combustion chamber. Then, the compression ratio of the combustion chamber 27 becomes higher than that of the engine of Patent Document 1. Therefore, this engine can achieve the first purpose.

With reference to FIG. 2, when the gutter valve 2 is lifted by the cam 30, the valve cover 7 moves together with the gutter valve 2. When the soot valve 2 is lifted to the maximum, most of the valve cover 7 is located in the secondary cylinder 4. When the soot valve 2 opens, the combustion chamber 27 facing the upper surface of the biston communicates with the external space of the engine.
In the first embodiment, the soot valve 2 is installed on the wall surface of the first portion of the combustion chamber 27 extended outside the main cylinder 1. In addition, the sum of the number of overhead valves and the number of sputum valves is set to three or more. Accordingly, the total area of the intake valve and the exhaust valve of the engine of the first embodiment is increased as compared with the conventional example having no soot valve outside the main cylinder. In the first embodiment, the overhead valves 25A and 25B are installed facing the upper surface of the piston. Therefore, the total of the area of the intake valve and the exhaust valve of the engine of the first embodiment is increased as compared with Patent Document 3 of the side valve type.
Therefore, when the engine rotates at a high speed, the efficiency of intake and exhaust of the engine of the first embodiment increases compared to the conventional example. This effect is not shown in Patent Document 1 and Patent Document 3.
Patent Document 3 does not describe the increase in the area of the side valve type intake valve and the exhaust valve.
Patent Document 2 has a description of providing a valve that slides with an overhead valve. However, this description is different from the first embodiment.

The second to fifth embodiments are alternatives to the elements of the first embodiment. In these embodiments, the first object can be achieved.
In these embodiments, only differences from the first embodiment will be described.
A second embodiment will be described.
With reference to FIG. 4, the secondary cylinder 4 is installed in the cylinder head 5. In this case, the gas passage in contact with the valve 2 is installed in the cylinder block. The soot valve 2 installed outside the cylinder is a side valve.
A third embodiment will be described.
5, instead of the spring 12, a pneumatic or hydraulic device 19 or an electromagnetic device or an electric device is used. These devices press the top surface 8 of the valve cover 7 against the bottom surface of the valve 2. These devices and the third spring 12 are devices that push the valve cover 7 toward the valve seat 16.
In Fig. 5, the pressure of combustion gas is applied to the compression ring 9 and the valve cover is pushed down. This depressing force must not isolate the bottom of the valve cover from the valve.
The above-described device including the hydraulic device 19 with a force equal to or greater than the pushing-down force causes the valve cover to face the valve seat 16 of the valve 2.

A fourth embodiment will be described.
Referring to FIG. 6, the valve 2 and the valve cover 7 are formed integrally.
In FIG. 6, a virtual joint surface between the valve 2 and the valve cover 7 is indicated by a one-dot chain line. In reality, there is no joint surface indicated by the alternate long and short dash line.
6, when the third spring 12 that presses the valve cover 7 is not installed, the second spring 31 that contacts the shaft portion of the valve 2 functions as an alternative to the third spring 12. The second spring 31 pulls the valve 2. For this reason, the installation of the spring 12 can be omitted.
If the third spring 12 is installed, the installation of the second spring 31 in contact with the shaft portion of the valve 2 can be omitted.

A fifth embodiment will be described.
With reference to FIG. 7, a ring groove for the compression ring 9 is provided on the inner wall of the sub cylinder 4. And the compression ring 9 is installed in this ring groove.
In order for the compression ring 9 to seal the combustion gas, when the soot valve 2 is closed, the compression ring 9 is positioned between the cylindrical side surface of the valve cover 7 and the cylindrical side surface of the valve cover 7. There must be. No ring groove is formed on the cylindrical side surface of the valve cover 7. Therefore, in this engine, the force of the combustion gas applied to the compression ring 9 does not push the valve cover 7 downward. Therefore, the engine shown in FIG. 7 can use a weaker spring than that of the engine shown in FIG.

The following sixth to tenth embodiments are added to the first to fifth embodiments. Sixth to tenth embodiments improve the first to fifth embodiments.
The sixth to tenth embodiments are not described in Patent Document 1 and Patent Document 3.
The eighth to tenth embodiments and the sixth embodiment are not described in Patent Document 2.
The sixth embodiment will be described with reference to FIGS. 8 and 9.
The sixth embodiment corresponds to the second aspect.
One end 10 of the sub cylinder 4 is installed at a position adjacent to the second valve seat 16 for the valve 2. The part of the secondary cylinder 4 adjacent to the valve 2 can be formed integrally with the part of the secondary cylinder 4 facing the compression ring 9 or as part of the cylinder head. When the soot valve 2 is opened, the umbrella portion of the soot valve 2 is located inside the sub cylinder 4.
When the central axis of the sub cylinder 4 not drawn from the portion of the central axis 37 of the main cylinder 1 that is located in the combustion chamber is seen, a part of the sub cylinder 4 faces a part of the semicircular surface 35 on the back side that cannot be seen. Form. The central axis 37 of the main cylinder 1 is indicated by a one-dot chain line. The non-visible half-circumferential surface 35 is the semi-circular surface of the portion adjacent to the valve 2 on the cylindrical side surface of the valve cover 7. A boundary 38 between the front half surface 40 visible from the portion of the central shaft 37 located in the combustion chamber and the invisible back half surface 35 is indicated by a four-dot chain line. This boundary 38 is orthogonal to a three-dot chain line 39 connecting the portion of the central axis 37 of the main cylinder 1 and the central axis of the sub cylinder 4.
A combustion chamber space in contact with a part of the outer peripheral surface 36 of the sub-cylinder 4 facing a part of the invisible back half peripheral surface 35 is not created.
When a portion of the sub cylinder 4 adjacent to the valve 2 is formed as a part of the cylinder head, the sub cylinder 4 facing a part of the outer peripheral surface 36 of the sub cylinder 4 and a part of the half peripheral surface 35 on the back side that cannot be seen. The inner peripheral surfaces of the same.
An opening 18 of the auxiliary cylinder 4 is provided on the upper side of the auxiliary cylinder 4.
A first gas passage 11 is provided between the second valve seat 16 for the soot valve 2 and the external space of the engine.
A second gas passage 21 that connects the inner space of the main cylinder 1 and the first gas passage 11 at a short distance while the soot valve 2 is open is provided. An opening 18 is included in the second gas passage 21. In FIG. 9, the opening 18 is indicated by a two-dot chain line.
The opening 18 faces the front-side semicircular surface 40 that can be seen from the portion where the central axis 37 of the main cylinder 1 is located in the combustion chamber. The front side semi-circumferential surface 40 that can be seen is the semi-peripheral surface of the part adjacent to the valve 2 on the cylindrical side surface.
The second gas passage 21 is included in the combustion chamber space surrounded by the second portion.
A plurality of pairs of valve covers 7, sub-cylinders 4, and openings 18 can be installed in the second portion that extends outside the main cylinder 1.

In the second embodiment, the volume of the combustion chamber expanded outside the main cylinder 1 is reduced and the compression ratio is higher than those of the engines shown in Patent Document 1 and Patent Document 3.
During the combustion stroke and the expansion stroke, the heat of the combustion gas is applied to a part of the cylindrical side surface at the top of the valve cover 7.
During the combustion stroke and the expansion stroke, the pressure of the combustion gas is applied to the portion adjacent to the valve 2 on the cylindrical side surface of the valve cover 7 in the direction from the central axis of the main cylinder 1 toward the central axis of the sub cylinder 4. . Then, when the portion adjacent to the valve 2 on the cylindrical side surface of the valve cover 7 is divided into two half-circumferential surface portions, a part of the sub-cylinder 4 having the outer peripheral surface 36 is invisible on the back-side semi-circumferential surface 35. Is pressed and comes into close contact. A part of the sub cylinder 4 having the outer peripheral surface 36 faces the half peripheral surface 35 on the back side that cannot be seen. Combustion gas cannot flow between the two surfaces that are in close contact. The heat of the combustion gas cannot flow into both sides that are in close contact.
Then, in the second embodiment, the area of the portion where the heat of the combustion gas is applied to the cylindrical side surface of the valve cover 7 is reduced as compared with the engine shown in Patent Document 3, and the heat loss amount of this engine is reduced. The larger the contact area, the lower the temperature of the cylindrical side surface. Therefore, the fuel consumption is improved and the knocking resistance is improved as compared with the engine shown in Patent Document 3.

A seventh embodiment will be described.
The seventh embodiment corresponds to the third aspect.
In the column of the prior art, a problem related to the improvement of combustion gas conversion efficiency and the increase in torque at high speed rotation is described.
This problem can be solved by the following settings. The length of the piston stroke of the engine shown in the first to sixth embodiments is not set smaller than the diameter of the piston. That is, the length of the stroke of the piston of the engine is made substantially equal to or larger than the diameter of the main piston.
This improves the combustion gas conversion efficiency compared to a short stroke engine. It also improves the reduction in intake efficiency of high-speed rotation of long stroke engines. As a result, improvement in conversion efficiency and increase in torque at high speed can be achieved at the same time. Therefore, the third purpose can be achieved.

The eighth embodiment will be described with reference to FIG.
A portion of the valve cover 7 adjacent to the soot valve 2 is heated by the combustion gas during the combustion stroke. In a spark ignition type engine, a high heat portion in the combustion chamber causes knocking. In a piston type engine, a high heat part in the combustion chamber reduces the filling rate of intake air.
In order to solve this problem, an injection valve 41 is added to the engine shown in the first to seventh embodiments. The injection valve 41 sprays oil toward the back surface of the portion adjacent to the valve 2 of the valve cover 7. The sbling 12 is installed in contact with the back surface. Then, the temperature of the part adjacent to the valve 2 on the cylindrical side surface of the valve cover 7 is lowered. Then, knocking is less likely to occur. Then, a compression ratio can be set high and thermal efficiency improves. Therefore, the third purpose is achieved.
Further, the filling rate of intake air does not decrease.

A ninth embodiment will be described.
In the engine shown in FIG. 11, the following settings are added to all the embodiments except the fourth embodiment.
The surface of the valve cover 7 that contacts the valve cover 2 is formed as a convex curved surface, and the surface of the valve cover 2 that contacts the valve cover 7 is formed as a concave curved surface. These two curved surfaces have the same curvature.
In the engine shown in FIG. 1, when the pressure in the combustion chamber suddenly increases, the portion of the valve cover 7 adjacent to the soot valve 2 is pressed against the side opposite to the piston 26. And the upper part adjacent to the valve 2 of the valve cover 7 is deformed. The bottom surface 3 of the valve 2 is not deformed. At this time, in the engine shown in FIG. 11, there is no gap between the two curved surfaces. The state where the two curved surfaces are in close contact is displayed as a solid line. When the pressure in the combustion chamber increases rapidly, the two curved surfaces in FIG. 11 are not isolated.

A tenth embodiment will be described.
7, if oil is supplied to the inner wall of the sub-cylinder 4, the gap between the cylindrical side surface of the valve cover 7 and the inner wall of the sub-cylinder 4 is caused by capillary action and movement of the valve cover 7. Oil penetrates into. During the intake stroke, oil that has entered the gap is sucked into the combustion chamber. Then, the oil consumption increases.
On the other hand, if the oil ring 22 is installed on the cylindrical side surface of the valve cover 7 as shown in FIG. 12, the oil consumption can be limited. However, the compression ring 9 installed on the inner wall of the sub cylinder 4 does not move. Therefore, the compression ring 9 cannot move the oil. Accordingly, in the case shown in FIG. 12, the compression ring 9 installed near the combustion chamber is insufficiently lubricated.
This problem is solved by adding the following settings.
As shown in FIG. 13, the upper compression ring 23 installed near the combustion chamber 27 is installed on the inner wall of the sub-cylinder 4, and the lower compression ring 24 is installed on the cylindrical side surface of the valve cover 7. The upper compression ring 23 is installed between the lower compression ring 24 and the combustion chamber 27. The upper end of the lower compression ring 24 when the soot valve 2 is closed is located adjacent to the lower end of the upper compression ring 23. A lower compression ring 24 is installed between the oil ring 22 and the upper compression ring 23. The oil ring 22 is installed on the cylindrical side of the part.
When the valve cover 7 moves, the lower compression ring 24 also moves. The moving lower compression ring 24 moves the remaining oil removed by the oil ring 22 to the lower end of the upper compression ring 23. Then, the upper compression ring 23 is lubricated.
An oil outlet is provided between the position of the lower compression ring 24 when the cam drives the valve cover 7 to the maximum and the position of the oil ring 22 when the valve 2 is closed. Then, the amount of oil that the lower compression ring 24 moves increases.

The figure explaining 1st embodiment. The figure explaining 1st embodiment. The figure when the sputum valve is opened. The figure explaining 1st embodiment. The alternative figure of the element of a first embodiment. The alternative figure of the element of a first embodiment. The alternative figure of the element of a first embodiment. The alternative figure of the element of a first embodiment. The figure explaining 2nd embodiment. The figure explaining 2nd embodiment. Illustration of examples improving the first to fifth embodiments Illustration of examples improving the first to fifth embodiments Illustration of examples improving the first to fifth embodiments Illustration of examples improving the first to fifth embodiments The figure of the output and torque of 3RZ-FE engine and 22R-E engine. The combustion chamber of Japanese Patent Publication No. 2000-282814. The figure of the engine of the 3rd mode of Japanese patent application No. 2008-120801. The second figure of Japanese Patent Publication No. 2001-355470.

DESCRIPTION OF SYMBOLS 1 ... Main cylinder 2 ... Saddle valve 3 provided outside main cylinder 3 ... Bottom face of soot valve 4 ... Sub cylinder 5 ... Cylinder head 6 ... Cylinder block 7 ... Valve Cover 8 ... Upper surface 9 facing the space in the combustion chamber of the valve cover ... Compression ring 10 ... Upper end 11 of the sub cylinder ... Gas passage 12 ... Spring 13 ... Valve cover Part 14 not contacting the bottom face of the soot valve on the upper surface ... Side valve 15 ... Combustion chamber space 16 obtained by subtracting the part where the valve cover protrudes from the combustion chamber space expanded outside the main cylinder The valve seat 17 of the soot valve ... the exhaust soot valve 18 ... the opening 19 of the sub cylinder ... the hydraulic device 20 ... the intake soot valve 21 ... the inner periphery of the main cylinder and the opening of the sub cylinder Connecting passage 22 .... Oil ring 23 ... Upper compression ring 24 ... Lower compression ring 25 ... Overhead valve 26 ... Piston 27 ... Combustion chamber 28 ... Cam 29 ... Overhead valve spring 30 ... Cam 31 in contact with soot valve ... Second spring 32 in contact with upper part of fourth valve ... Electromagnetic drive device 33 ... Overhead valve 34 used as intake soot valve ..Exhaust soot valve 35 provided on the outside of the main cylinder: A part of the upper cylindrical side surface and the back half-circumferential surface 36 that cannot be seen from the portion located in the combustion chamber of the central axis of the main cylinder The outer peripheral surface 37 of a part of the sub-cylinder facing a part of the semicircular surface on the back side that cannot be seen from the portion located in the combustion chamber of the central axis ... the central axis 38 of the main cylinder ... the combustion chamber of the central axis of the main cylinder Seen from the part located at Boundary 39 between the front half-surface and the invisible back half-circumference surface ... A three-dot chain line 40 connecting the central axis of the main cylinder and the central axis of the sub-cylinder ... a part of the upper cylindrical side surface and the main cylinder Front side semi-peripheral surface 41 seen from the part of the central axis of the combustion chamber located in the combustion chamber 41...

Claims (11)

A combustion chamber is formed between the piston and the cylinder head, the combustion chamber is extended to the outside of the main cylinder, and an inner wall surface of the combustion chamber includes a first portion and a second portion, and the first portion is in the main cylinder. A portion of the inner wall surface facing the upper surface of the piston installed in the second portion, the second portion is a portion of the inner wall surface extended to the outside of the main cylinder, the sub-cylinder is installed outside the main cylinder, A soot valve is installed in the second part, and the soot valve has a second driving device for driving a shaft portion of the soot valve, and when the soot valve is opened, gas is used for the soot valve and the soot valve. A part that passes between the second valve seat and covers a bottom surface of the umbrella portion of the valve valve is provided, the part reciprocates in the sub cylinder, the part has a cylindrical side surface, The umbrella part between the second valve seat and the part Located, means for contacting the second valve seat, the umbrella part and the parts are provided, the valve and the parts are integrally driven by the second driving device and the means, A piston type engine in which a compression ring is installed at a position sandwiched between the inner wall of the sub-cylinder and the cylindrical side surface of the component, and the component is positioned in contact with the bottom surface of the valve. In
An overhead valve is installed in the first portion, and when the overhead valve is opened, the gas passes between the overhead valve and a first valve seat for the overhead valve, the overhead valve being a first spring and With a first drive,
The sum of the overhead valve and the soot valve includes at least one pair of an intake valve and an exhaust valve,
A piston type engine having the above-mentioned parts, wherein the sum of the number of overhead valves and the number of soot valves is three or more. A combustion chamber is formed between the piston and the cylinder head, the combustion chamber is extended to the outside of the main cylinder, and an inner wall surface of the combustion chamber includes a first portion and a second portion, and the first portion is in the main cylinder. A portion of the inner wall surface facing the upper surface of the piston installed in the second portion, the second portion is a portion of the inner wall surface extended to the outside of the main cylinder, the sub-cylinder is installed outside the main cylinder, A soot valve is installed in the second part, the soot valve has a second driving device for driving the shaft portion of the soot valve, and a part covering the bottom surface of the umbrella part of the soot valve is provided. Reciprocating in the sub-cylinder, the component has a cylindrical side surface, the umbrella portion is located between the second valve seat for the valve and the component, the second valve seat and the Means for tightly attaching the umbrella part to the component The compression ring is installed at a position where the second valve and the part are integrally driven by the second driving device and the means, and are sandwiched between the inner wall of the sub cylinder and the cylindrical side surface of the part. In the piston type engine having the above-mentioned elements, the component is located in contact with the bottom surface of the valve.
An overhead valve is installed in the first portion, and when the overhead valve is opened, the gas passes between the overhead valve and a first valve seat for the overhead valve, the overhead valve being a first spring and With a first drive,
The sum of the overhead valve and the soot valve includes at least one pair of an intake valve and an exhaust valve,
A plurality of exhaust soot valves are installed in the second part, and all the soot valves installed in the second part are limited to exhaust soot valves,
A piston-type engine having the above-mentioned parts, wherein at least one intake overhead valve is installed in the first part. A plurality of intake soot valves are installed in the second part, and the soot valves installed in the second part are limited to intake soot valves,
The piston-type engine having the component according to claim 1, wherein at least one exhaust overhead valve is installed in the first portion. A combustion chamber is formed between the piston and the cylinder head, the combustion chamber is extended to the outside of the main cylinder, and an inner wall surface of the combustion chamber includes a first portion and a second portion, and the first portion is in the main cylinder. A portion of the inner wall surface facing the upper surface of the piston installed in the second portion, the second portion is a portion of the inner wall surface extended to the outside of the main cylinder, the sub-cylinder is installed outside the main cylinder, A soot valve is installed in the second part, and the soot valve has a second driving device for driving a shaft portion of the soot valve, and when the soot valve is opened, gas is used for the soot valve and the soot valve. A part passing between the second valve seat and covering the bottom surface of the umbrella portion of the soot valve is provided, the part reciprocates in the sub cylinder, the part has a cylindrical side surface, and the soot Said second valve seat and said part for valve The umbrella portion is located between the second valve seat, the umbrella portion, and the component, and a means for closely contacting the component is provided. Are integrally driven, a compression ring is installed at a position sandwiched between the inner wall of the sub-cylinder and the cylindrical side surface of the component, the component is positioned in contact with the bottom surface of the valve, In a piston-type engine with elements,
One or more arbitrary number of overhead valves are installed in the first part, and all the overhead valves provided in the first part are intake overhead valves,
The overhead valve has a first spring and a first drive;
The sum of the number of overhead valves and the number of sputum valves is three or more,
A piston type engine having the above-mentioned parts, wherein an exhaust soot valve is provided in the second part. One end of the sub cylinder is installed at a position adjacent to the second valve seat,
When the central axis of the sub-cylinder is viewed from the portion of the central axis of the main cylinder located in the combustion chamber, a part of the sub-cylinder is formed facing a part of the rear half surface that is not visible,
The invisible back side semi-peripheral surface is a semi-peripheral surface of a portion adjacent to the valve on the cylindrical side surface,
No space for the combustion chamber is created outside the part of the sub-cylinder facing a part of the semicircular surface on the back side,
An opening of the secondary cylinder is provided on the secondary cylinder,
A first gas passage is installed between the second valve seat and the external space of the engine;
A second gas passage that connects the main cylinder inner space and the first gas passage at a short distance while the soot valve is open is installed, and the opening is formed in the second gas passage. Included,
The said opening part faces the semicircular surface of the front side of the said cylindrical side surface which can be seen from the part in which the center axis | shaft of the said main cylinder is located in a combustion chamber, The said Claim 1 to the said Claim 4 characterized by the above-mentioned. Piston engine with the above parts. 6. The piston-type engine having the component according to claim 1, wherein a length of a stroke of the piston of the engine is not set smaller than a diameter of the piston. The above-mentioned claim 1 to the above-mentioned claim, wherein an injection valve that sprays oil toward the back surface of the part adjacent to the soot valve of the part is added, and a third sbling is installed in contact with the back surface. A piston-type engine having the above-described parts described in Item 5. In the secondary cylinder, a groove for the compression ring is installed,
5. The piston-type engine having the parts according to claim 1, wherein the compression ring is installed in the groove. A surface of the valve cover that contacts the valve cover is formed as a convex curved surface, a surface of the valve valve that contacts the valve cover is formed as a concave curved surface, and the curvatures of the two curved surfaces coincide with each other.
Do not integrate the valve cover and the valve
The piston-type engine having the component according to claim 1 or 5, wherein the valve cover and the umbrella portion of the soot valve are located in contact with each other. An upper compression ring is installed on the inner wall of the secondary cylinder, the upper compression ring is installed near the combustion chamber;
The lower compression ring is installed on the cylindrical side of the part,
The upper compression ring is installed between the lower compression ring and the combustion chamber;
The upper end of the lower compression ring when the soot valve is closed is located adjacent to the lower end of the upper compression ring,
The oil ring is installed on the cylindrical side of the part,
6. The piston-type engine having the parts according to claim 1 and 5, wherein the lower compression ring is installed between the oil ring and the upper compression ring. A device for pushing the component toward the second valve seat is the means,
A third spring installed in contact with the part is used as the device for pushing the part toward the second valve seat;
6. The piston-type engine having the component according to claim 1 or 5, wherein the third spring does not face a space in the combustion chamber.

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