US20100180851A1 - Piston engine comprising member to cover bottom face of valve head of poppet valve - Google Patents
Piston engine comprising member to cover bottom face of valve head of poppet valve Download PDFInfo
- Publication number
- US20100180851A1 US20100180851A1 US12/688,885 US68888510A US2010180851A1 US 20100180851 A1 US20100180851 A1 US 20100180851A1 US 68888510 A US68888510 A US 68888510A US 2010180851 A1 US2010180851 A1 US 2010180851A1
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- United States
- Prior art keywords
- valve
- poppet valve
- face
- poppet
- piston
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
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Classifications
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01L—CYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES
- F01L1/00—Valve-gear or valve arrangements, e.g. lift-valve gear
- F01L1/46—Component parts, details, or accessories, not provided for in preceding subgroups
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01L—CYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES
- F01L1/00—Valve-gear or valve arrangements, e.g. lift-valve gear
- F01L1/28—Valve-gear or valve arrangements, e.g. lift-valve gear characterised by the provision of coaxial valves; characterised by the provision of valves co-operating with both intake and exhaust ports
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01L—CYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES
- F01L3/00—Lift-valve, i.e. cut-off apparatus with closure members having at least a component of their opening and closing motion perpendicular to the closing faces; Parts or accessories thereof
- F01L3/20—Shapes or constructions of valve members, not provided for in preceding subgroups of this group
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01L—CYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES
- F01L1/00—Valve-gear or valve arrangements, e.g. lift-valve gear
- F01L1/20—Adjusting or compensating clearance
- F01L1/22—Adjusting or compensating clearance automatically, e.g. mechanically
- F01L1/24—Adjusting or compensating clearance automatically, e.g. mechanically by fluid means, e.g. hydraulically
- F01L1/245—Hydraulic tappets
- F01L1/25—Hydraulic tappets between cam and valve stem
- F01L1/252—Hydraulic tappets between cam and valve stem for side-valve engines
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01L—CYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES
- F01L1/00—Valve-gear or valve arrangements, e.g. lift-valve gear
- F01L1/02—Valve drive
- F01L1/04—Valve drive by means of cams, camshafts, cam discs, eccentrics or the like
- F01L1/047—Camshafts
- F01L1/053—Camshafts overhead type
- F01L2001/0535—Single overhead camshafts [SOHC]
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01L—CYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES
- F01L1/00—Valve-gear or valve arrangements, e.g. lift-valve gear
- F01L1/02—Valve drive
- F01L1/04—Valve drive by means of cams, camshafts, cam discs, eccentrics or the like
- F01L1/047—Camshafts
- F01L1/053—Camshafts overhead type
- F01L2001/0537—Double overhead camshafts [DOHC]
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01L—CYCLICALLY OPERATING VALVES FOR MACHINES OR ENGINES
- F01L1/00—Valve-gear or valve arrangements, e.g. lift-valve gear
- F01L1/02—Valve drive
- F01L1/04—Valve drive by means of cams, camshafts, cam discs, eccentrics or the like
- F01L1/047—Camshafts
- F01L2001/054—Camshafts in cylinder block
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F01—MACHINES OR ENGINES IN GENERAL; ENGINE PLANTS IN GENERAL; STEAM ENGINES
- F01M—LUBRICATING OF MACHINES OR ENGINES IN GENERAL; LUBRICATING INTERNAL COMBUSTION ENGINES; CRANKCASE VENTILATING
- F01M11/00—Component parts, details or accessories, not provided for in, or of interest apart from, groups F01M1/00 - F01M9/00
- F01M11/02—Arrangements of lubricant conduits
- F01M2011/022—Arrangements of lubricant conduits for lubricating cylinders
Definitions
- a second object is to lower a temperature of the valve when it is used as an exhaust valve.
- the device to bias the member toward the second valve sheet may be one of a third spring provided with abutting the member, a pneumatic unit provided with abutting the member and a hydraulic unit provided with abutting the member.
- the two half circumferences are referred to as a first half circumference which is close to the central axis of the main cylinder and a second half circumference which is away from the central axis of the main cylinder.
- FIGS. 10 to 13 are views showing embodiments to improve the first to fifth embodiments.
- FIG. 16 is a view of the engine according to the third aspect of Japanese patent application No. 2008-120801.
- the overhead valves 25 A and 25 B are provided in the first part which faces with the upper face of the piston 26 . When the overhead valves 25 A and 25 B are open, gas passes through gaps between the overhead valves 25 A and 25 B and valve sheets of them.
- the overhead valves 25 A and 25 B are provided with springs 29 A and 29 B respectively.
- the overhead valves 25 A and 25 B are respectively provided with cams 28 A and 28 B as a first drive unit to lift the overhead valves 25 A and 25 B.
- the third example will be described with reference to FIG. 3 .
- the valve cover 7 and poppet valve 2 are driven by the cam 30 which lifts the poppet valve 2 .
- the cam 30 functions as a second drive unit.
- the spring 12 is one of means to let the second valve sheet 16 , poppet valve 2 and valve cover 7 contact intimately with one another.
- the third embodiment will be described.
- the compression ring 9 In order that the compression ring 9 seals the combustion gas, the compression ring 9 is wedged between the cylindrical side face of the valve cover 7 and the inner wall of the sub cylinder 4 . A ring groove is not provided on the cylindrical side face of the valve cover 7 . Therefore in this engine, the force of the combustion gas given to the compression ring 9 does not push the valve cover 7 downward. Therefore in the engine shown in FIG. 7 , a weaker spring may be employed than the spring of the engine shown in FIG. 1 .
- the end 10 of the sub cylinder 4 is disposed at a position adjacent to the second valve sheet 16 of the poppet valve 2 .
- the part adjacent to the poppet valve 2 of the sub cylinder 4 may be formed integrally with the part facing with the compression ring 9 of the sub cylinder 4 , or may be formed as a part of the cylinder head.
- the valve head of the poppet valve 2 is located inside the sub cylinder 4 .
- the cylindrical side face of the valve cover 7 adjacent to the poppet valve 2 is sectioned into two half surrounding faces.
- the two half surrounding faces are a first half surrounding face 40 having the first half circumference and a second half surrounding face 35 having the second half circumference.
- the opening 18 faces with the first half surrounding face 40 .
- the second gas path 21 is included in the combustion chamber surrounded by the second part.
- a plurality of the combinations of the valve cover 7 , sub cylinder 4 and the opening 18 may be provided in the second part which extends outside the main cylinder 1 .
- the engines of the first to sixth embodiments are further configured such that the length of the piston stroke is not shorter than the diameter of the piston. That is, the length of the piston stroke is approximately same as or longer than the diameter of the main piston in these engines.
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- General Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Geometry (AREA)
- Combustion Methods Of Internal-Combustion Engines (AREA)
Abstract
To achieve high compression ratio and lower temperature of the exhaust poppet valve in an engine provided with a poppet valve on an extend part of a combustion chamber outside a main cylinder, disclosed is a valve cover having a cylindrical side face and upper face, an compression ring either the cylindrical side face and an inner wall of the sub cylinder, means to contact closely a bottom face of a poppet valve and the upper face of the valve cover, the upper part of the valve cover occupying most part of the combustion chamber facing with the bottom face, the valve cover moves along with the poppet valve when the poppet valve is lifted, a combination of overhead valves and the poppet valve including one intake valve and one exhaust valve, and total number of the overhead valve and poppet valve is not less than 3.
Description
- 1. Field of the Invention
- The present invention relates to a piston engine comprising a member to cover a bottom face of a valve head of a poppet valve. When the combustion chamber extends outside the main cylinder, the member occupies a space facing with the bottom face of the poppet valve provided outside a main cylinder in a combustion chamber.
- 2. Description of the Related Art
- The suction resistance and exhaust resistance of a four cycle engine are high when it rotates at high speed. The suction lifts in this engine are extremely small in the initial stages of the periods when the suction valve is open. The initial stages are shorter when the engine rotates at a higher speed. This restricts the inflow of suction gas. As a result, in the initial stages of the periods when the suction valve is open, the pressure in the cylinder is lower than the pressure at the back of the piston.
- Under this condition, the piston keeps moving downward against the pressure on it. As a result, the negative work increases. This increases the loss caused by the suction resistance, so that the torque lowers.
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FIG. 14 shows the engine performance curves shown on page 90 of No. 434 issued in November, 1995 of a magazine entitled “Internal Combustion Engine” published by Sankaido. With reference toFIG. 14 , the torque of a four cycle engine is lower than the maximum torque points L1 and L2 on torque curves when the engines rotate at speeds higher than those for these points. - The exhaust lifts in a four cycle engine are extremely smaller in the initial stage of the period when the exhaust valve is open until the piston reaches the bottom dead point of each exhaust stroke than in the middle stage of this period. Consequently, when the engine rotates at high speed, the pressure created in the cylinder when the piston is at the bottom dead point is high. As a result, just after the piston leaves the bottom dead point, the exhaust resistance causes a great loss.
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FIG. 15 shows the side valve engine disclosed inPatent document 1. Themain combustion chamber 127 of this engine has an extension outside the cylinder. This makes it possible to fit another suction valve and another exhaust valve that face the top of the piston. - The space between the suction and exhaust valves is narrowed to make the combustion chamber compact in
Patent document 1. - However, the volume of the main combustion chamber is increased by the space between the wall fitted with a side valve and the surface facing the wall. The volume of this space increases with the lift of the side valve. Consequently, the combustion chamber having a suction valve facing the top of the piston and a side valve cannot have a high combustion ratio, so that the engine efficiency is low.
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FIG. 17 shows a side valve engine described inpatent document 3. InFIG. 17 , there is a space of a combustion chamber between an edge of a guide hole facing with the combustion chamber and a valve sheet for the intake valve. According toFIG. 17 , the combustion chamber extends outside thevolume changing member 117 in a view observing from the central axis of the cylinder toward the volume changing member. The volume of the combustion chamber increases by this extended portion. -
Reference numeral 118 denotes the guide hole.Reference numeral 113 denotes the intake valve.Reference numeral 117 denotes the volume changing member.Reference numeral 127 denotes the combustion chamber. - The side valve internal combustion engine of
patent document 3 is provided with a pair of an intake and exhaust valves provided at the lateral periphery of the cylinder. Therefore, the total area of the pair of intake and exhaust valves of the side valve internal combustion engine ofpatent document 3 is smaller than that of an engine provided with four valves at a wall facing with an upper face of a piston in the wall of the combustion chamber. - In the side valve internal combustion engine of
patent document 3, a part protruding into the combustion chamber of the volume changing member is heated to high temperature by the combustion gas while the intake valve is closed. - Combustion occurs intermittently in a piston engine. An inner wall of a combustion chamber is cooled by intake gas in a piston engine. In a spark-ignition engine, mixture gas thus forms a quench zone along with an inner wall of a combustion chamber. This quench zone prevents high heat from flowing to the inner wall of the combustion chamber.
- When the exhaust poppet valve opens, both a bottom face of a valve head of the exhaust poppet valve and an upper face facing with a gas passage of the valve head are exposed to the combustion gas. The temperature of the exhaust poppet valve thus gets high. When the piston is under high load, the quench zone is poorly formed along with the bottom face of the valve head of the exhaust poppet valve. Therefore, the mixture zone along with the bottom face self-ignites. When the amount of self-ignited mixture increases, the quench zone is broken also at a part facing with the inner wall of the combustion chamber other than the bottom face. As a result, knocking occurs.
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FIG. 16 shows the engine ofpatent document 2. - When the sliding valve shown in the third aspect of
patent document 2 is used as an exhaust valve, both upper and lower faces of a first compression ring of the sliding valve are exposed to the combustion gas at the beginning of exhaust strokes.Reference numeral 8 denotes the first compression ring. Thus, the first compression ring is heated to the ignition temperature of the lubricant or more. The first compression ring is then seized up. The engine of Japanese patent application No. 2008-120801 comprises a sub cylinder outside the main cylinder. - If the strokes of the piston are longer than its diameter, the combustion gas conversion efficiency is high, but the suction efficiency is low when the engine rotates at high speed. The low suction efficiency leads to low torque. If the piston strokes are shorter than the piston diameter, the suction efficiency is high when the engine rotates at high speed, but the combustion gas conversion efficiency is low.
- Therefore, long strokes of the pistons of conventional spark ignition engines have been incompatible with torque increases that may be caused when the engines rotate at high speed.
- Patent document 1: Japanese Patent Application Publication No. 2000-282814 (JP2000-282814A)
- Patent Document 2: Japanese Patent Application No. 2008-120801, Japanese Patent No. 4230529
- Patent document 3: Japanese Patent Application Publication No. 2001-355470
- A first object is to raise compression ratio of an engine which comprises a valve on a wall of an extended part of a combustion chamber outside a main cylinder.
- A second object is to lower a temperature of the valve when it is used as an exhaust valve.
- A third object is to improve fuel efficiency of a piston engine.
- Hereinafter described is a structure of a piston engine according to a first aspect of the present invention.
- The piston engine of the present invention comprises a cylinder head, a cylinder block, a main cylinder, a piston, a sub cylinder, an overhead valve and a poppet valve. A member to cover a bottom face of a valve head of the poppet valve is provided.
- The piston reciprocates in the main cylinder. A combustion chamber is defined between the piston and the cylinder head. The combustion chamber further extends outside the main cylinder. An inner wall of the combustion chamber comprises a first part and a second part. The first part represents a part of the inner wall which faces with an upper face of the piston. The second part represents the inner wall of an extended part outside the main cylinder. The sub cylinder is provided outside the main cylinder.
- The poppet valve is provided on the second part of the inner wall. The poppet valve is provided with a second drive unit to drive a stem of the poppet valve. When the poppet valve is open, gas passes through between the poppet valve and a second valve sheet of the poppet valve.
- The member reciprocates in the sub cylinder, and includes a cylindrical side face.
- The valve head positions between the second valve sheet and the member.
- Means to contact the second valve sheet, the member and the valve head intimately with one another is provided. The means may be a combination of the poppet valve integrally formed with the member and a device to shift the member toward the second valve sheet, or may be a device to bias the member toward the second valve sheet.
- The device to shift the member toward the second valve sheet may be one of a third spring provided with abutting the member, a pneumatic unit provided with abutting the member, a hydraulic unit provided with abutting the member and a second spring provided with abutting the stem of the poppet valve.
- The device to bias the member toward the second valve sheet may be one of a third spring provided with abutting the member, a pneumatic unit provided with abutting the member and a hydraulic unit provided with abutting the member.
- The second drive unit and the means drive the poppet valve and the member integrally.
- A compression ring is provided at a position wedged between an inner wall of the sub cylinder and the cylindrical side face of the member.
- The member is located with abutting the bottom face of the poppet valve.
- The overhead valve is provided on the first part of the inner wall. The overhead valve is provided with a spring and a first drive unit. When the overhead valve is open, gas passes through between the overhead valve and a valve sheet of the overhead valve. When the poppet valve is open, gas passes through between the poppet valve and a second valve sheet of the poppet valve. The gas is either intake gas flowing into the combustion chamber or combustion gas flowing out from the combustion chamber.
- A combination of the overhead valve and the poppet valve includes at least one intake valve and one exhaust valve.
- The total number of the overhead valve and poppet valve is not less than 3.
- About a structure of a piston engine according to a second aspect of the present invention, only the difference from the first aspect is described below.
- The sub cylinder is provided at a position where one end thereof is located adjacent to the second valve sheet.
- The whole circumference of the cylindrical side face of the member adjacent to the poppet valve is sectioned into two half circumferences by a line which is perpendicular to a line connecting the central axis of the main cylinder to the central axis of the sub cylinder intersecting at the central axis of the sub cylinder.
- The two half circumferences are referred to as a first half circumference which is close to the central axis of the main cylinder and a second half circumference which is away from the central axis of the main cylinder.
- The cylindrical side face of the member adjacent to the poppet valve is sectioned into two half surrounding faces. The two half surrounding faces are a first half surrounding face having the first half circumference and a second half surrounding face having the second half circumference.
- A part adjacent to the second valve sheet of the sub cylinder faces with the second half surrounding face.
- A fixed wall, which is located outside the combustion chamber extended outside the main cylinder, is formed adjacent to the inner wall facing with the second half surrounding face of the sub cylinder.
- An opening of the sub cylinder is provided in the vicinity of the one end of the sub cylinder.
- A first gas path is provided between the second valve sheet and outside of the engine. A second gas path is provided which communicates a space inside the main cylinder and the first gas path in a short distance when the poppet valve is open, and the second gas path includes the opening.
- The opening faces with the first half surrounding face.
- According to the piston engine of the second aspect, the area heated by the combustion gas is reduced in the cylindrical side face of the
valve cover 7 compared to that of the engine ofpatent document 3, and thus the amount of thermal loss is reduced in this engine. As a result, the third object is achieved in the second aspect. - About a structure of a piston engine according to a third aspect of the present invention, only the difference from the first aspect is described below.
- According to the engines of the first and second aspects, a stroke length of the piston is not shorter than a diameter of the piston.
- According to the piston engine of the third aspect conversion efficiency of the combustion gas is improved compared to short stroke engines. Also, decrease of intake efficiency is improved, which occurs in long stroke engines rotating at high speed. As a result, it becomes possible to strike the improvement of conversion efficiency and increase of torque in balance. Thus, the third object is achieved in the third aspect.
- The piston engines according to the three aspects of the present invention may be spark-ignition engines or compression-ignition engines, and the spark-ignition engines may be 2-stroke engines or 4-stroke-engines. When the engine of the invention is a spark-ignition engine, a spark plug may be provided anywhere on the wall of the combustion chamber.
- According to the engines of the three aspects of the present invention, the volume of the combustion chamber reduces by the volume of an upper part of the member which protrudes into the space in the combustion chamber which would face with the closed poppet valve if the member were not provided. Therefore, the engines can achieve high compression ratio of the combustion chamber. Thus, the first object is achieved.
- Further, a total area of the intake and exhaust valves of the engine according to the three aspects of the present invention is larger than engines provided with overhead valves only in a main cylinder. Therefore, intake and exhaust resistance reduces especially when rotating at high speed. Output power of the engine of the invention thus can increase.
-
FIGS. 1 to 3 are views showing the first embodiment, wherein: -
FIG. 2 is a view when the poppet valve is open. -
FIGS. 4 to 7 are views showing modifications of the first embodiment. -
FIGS. 8 and 9 are views showing the second embodiment. -
FIGS. 10 to 13 are views showing embodiments to improve the first to fifth embodiments. -
FIGS. 14 to 17 are views showing prior art, wherein: -
FIG. 14 is a graph showing power output and torque of the 3RZ-FE engine and 22R-E engine; -
FIG. 15 is a view of the combustion chamber of Japanese patent application publication No. 2000-282814; -
FIG. 16 is a view of the engine according to the third aspect of Japanese patent application No. 2008-120801; and -
FIG. 17 is FIG. 2 of Japanese patent application publication No. 2001-355470. - A first embodiment will be described.
- The first embodiment is included in the first aspect.
- A piston engine shown in
FIGS. 1 and 2 comprises acylinder head 5, acylinder block 6, amain cylinder 1, apiston 26, asub cylinder 4,overhead valves poppet valve 2. - The
piston 26 reciprocates in themain cylinder 1. Acombustion chamber 27 is defined between thecylinder head 5 and thepiston 26. Thecombustion chamber 27 further extends outside themain cylinder 1. An inner wall of thecombustion chamber 27 comprises a first part and a second part. The first part represents the inner wall which faces with an upper face of thepiston 26. The second part represents the inner wall of the extended part outside themain cylinder 1. - The
combustion chamber 27 may extend both right and left sides outside themain cylinder 1. - The
sub cylinder 4 is installed in thecylinder block 6 which locates outside themain cylinder 1. - The
overhead valves piston 26. When theoverhead valves overhead valves - The
overhead valves springs overhead valves cams overhead valves - When the
overhead valve 25A is configured as an intake valve and theoverhead valve 25B is configured as an exhaust valve, theoverhead valve 25A opens by thecam 28A during an intake stroke of thepiston 26 and theoverhead valve 25B opens by thecam 28B during an exhaust stroke of thepiston 26. - The
cams overhead valves - The
poppet valve 2 is provided on the second part extended outside themain cylinder 1. A plurality ofpoppet valves 2 may be provided in the second part. Abottom face 3 of thepoppet valve 2 denotes a bottom face of a valve head of thepoppet valve 2. At the periphery of an upper face of the valve head, thepoppet valve 2 has a face which intimately contacts with asecond valve sheet 16 of thepoppet valve 2 when thepoppet valve 2 is closed. An opening is provided inside thesecond valve sheet 16 of thepoppet valve 2, and the opening communicates to outside of the engine. When thepoppet valve 2 is closed, the valve head of thepoppet valve 2 positions at the opening. Thepoppet valve 2 is provided with acam 30 which abuts thepoppet valve 2. - When the
poppet valve 2 is open, intake or exhaust gas passes though a gap between thepoppet valve 2 and thesecond valve sheet 16. That is, thepoppet valve 2 can be used as either an intake valve or an exhaust valve. - When the
poppet valve 2 is used as an intake valve, it opens by thecam 30 during an suction stroke of thepiston 26. - When the
poppet valve 2 is used as an exhaust valve, it opens by thecam 30 during an exhaust stroke of thepiston 26. - The
cam 30 functions as a second drive unit to lift thepoppet valve 2. - The
cam 30 of thepoppet valve 2 may be replaced with an electromagnetic unit or a hydraulic unit. - Three examples of providing the intake and exhaust valves will be described. The three examples relate to the
overhead valves poppet valve 2. - The features shown in the three examples are not disclosed in
patent document 3. - In the three examples, the total number of the overhead valve and the poppet valve is not less than 3.
- In the first example, a plurality of exhaust poppet valves are provided on the second part, and the poppet valves provided on the second part are limited to exhaust poppet valves. This feature is not disclosed in
patent document 3. At least one overhead intake valve is provided on the first part. - Therefore, in the first example, it becomes possible to increase the number and the area of the exhaust poppet valves provided on the second part compared to the engines of
patent documents - When the exhaust poppet valves are open, the bottom faces 3 are covered with the
upper face 8 of thevalve cover 7 described below and the bottom faces 3 do not contact with the combustion gas. The temperature of the exhaust poppet valves thus does not rise high compared to the exhaust valve of thepatent document 1. It is possible to lower the temperature of only the exhaust poppet valves provided on the second part. Therefore, the second object is partly achieved in this engine. - The upper and lower faces of the
compression ring 9 are not exposed to the combustion gas at a time. Therefore, the temperature of thecompression ring 9 does not rise high compared to the third aspect ofpatent document 2 where the sliding valve is used as an exhaust valve. - In the first example, the amount of the combustion gas passing through each poppet valve provided on the second part is reduced compared to the exhaust poppet valve of
patent document 3, and the highest temperature of the plurality of exhaust poppet valves becomes lower. Therefore, resistance to knocking of the first example is improved compared topatent document 3. - The second example will be described.
- A plurality of intake poppet valves are provided on the second part, and the poppet valves provided on the second part is limited to intake valves. This feature is not disclosed in
patent document 3. At least one exhaust overhead valve is provided on the first part. Therefore, in the second example, it becomes possible to increase the number and the area of the intake valves compared to the engines ofpatent documents - The third example will be described with reference to
FIG. 3 . - One or more overhead valve is provided on the first part of the inner wall of the
combustion chamber 27, and all overhead valve provided in the first part is theintake poppet valve 33. Theexhaust poppet valve 34 is provided on the second part extended outside themain cylinder 1. It becomes possible to prevent the temperature of theexhaust poppet valve 34 from rising high according to the same ground described in the first example for explaining the temperature of the exhaust poppet valves. Theexhaust valve 34 does not lower filling rate of intake. Therefore, the second object is perfectly achieved in this engine. The temperature of theintake valve 33 does not rise high. - According to this feature, the wall of the combustion chamber does not have in any part a higher temperature than the exhaust valves described in the description of the related art. Therefore, when the piston is under a high load, a quench zone is formed along with the entire wall of the combustion chamber.
- As a result, in the case of a spark-ignition engine, resistance to knocking is improved compared to the engines of
patent documents - Piston engines can operate at least with a combination of one intake valve and one exhaust valve. Therefore, when a combination of the
overhead valves poppet valve 2 includes at least one intake valve and one exhaust valve, the piston engine of the first embodiment can operate whether the other valve than the combination is configured as an intake valve or an exhaust valve. - The total number of the overhead valves and the poppet valve is not less than 3.
- It is described that the embodiment comprises the two
overhead valves - The piston engine of the first embodiment comprises a
valve cover 7. - The
valve cover 7 reciprocates in thesub cylinder 4. Thevalve cover 7 covers thebottom face 3 of thepoppet valve 2. Thevalve cover 7 positions with its upper part being protruded into an inner space of thecombustion chamber 27. - The
valve cover 7 comprises a cylindrical side face, an upper face and a back face. The back face abuts aspring 12. A lower part of the cylindrical side face faces with an inner wall of thesub cylinder 4. - The
valve cover 7 andpoppet valve 2 are driven by thecam 30 which lifts thepoppet valve 2. Thecam 30 functions as a second drive unit. - A central axis of a stem of the
poppet valve 2 is identical to or approximately parallel to a central axis of thesub cylinder 4. Therefore, when thecam 30 lifts thepoppet valve 2, thevalve cover 7 moves along with thepoppet valve 2 and the lower part of thevalve cover 7 accordingly moves inside thesub cylinder 4. Therefore, thecam 30 of thepoppet valve 2 also functions as a drive unit to lift thevalve cover 7. - A space is defined between the
valve sheet 16 of thepoppet valve 2 and anupper end 10 of thesub cylinder 4. Theupper end 10 faces with the space of thecombustion chamber 27. - A ring groove for a
compression ring 9 is provided on the cylindrical side face of thevalve cover 7. Thecompression ring 9 is disposed to this ring groove. This feature is not shown inpatent document 3. - When the
poppet valve 2 is closed, thecompression ring 9 is wedged between the inner wall of thesub cylinder 4 and the ring groove. Since thecompression ring 9 is wedged between the inner wall of thesub cylinder 4 and the cylindrical side face of thevalve cover 7 when thepoppet valve 2 is closed, thecombustion chamber 27 is sealed with thecompression ring 9 so that combustion gas does not leak from thecombustion chamber 27 through the gap between thevalve cover 7 and the inner wall of thesub cylinder 4 into a space where thevalve cover 7 does not occupy in thesub cylinder 4. - A
spring 12 for thevalve cover 7 is provided with abutting the back face of thevalve cover 7, in order that theupper face 8 of thevalve cover 7 intimately contacts with thebottom face 3 of thepoppet valve 2. Thespring 12 biases thevalve cover 7 to let it abut thebottom face 3 of thepoppet valve 2. Thevalve cover 7 andpoppet valve 2 are consequently driven integrally by thecam 30 andspring 12. - The
spring 12 is one of means to let thesecond valve sheet 16,poppet valve 2 andvalve cover 7 contact intimately with one another. - The
spring 12 biases thevalve cover 7 toward thesecond valve sheet 16. - The
spring 12 also functions as a valve spring of thepoppet valve 2 which may be provided with abutting thepoppet valve 2. In the embodiment shown inFIG. 1 , the valve spring in contact with thepoppet valve 2 is not provided. By providing thespring 12 for thevalve cover 7, the valve spring abutting thepoppet valve 2 can be omitted. That is, the valve spring abutting the stem of thepoppet valve 2 is not essential. As a matter of course, the valve spring abutting the stem of thepoppet valve 2 may be further provided. - While the piston is in compression and combustion strokes, combustion gas flows toward the ring groove through the gap between the cylindrical side face of the
valve cover 7 and the inner wall of thesub cylinder 4. The combustion gas flows in one direction. Then, thecompression ring 9 is subjected to a force in the direction to compress thespring 12. Accordingly, the combustion gas blows thevalve cover 7. Therefore, it is necessary that thespring 12 is stronger than the combustion gas pressure applied to thecompression ring 9. - The
valve cover 7 is not driven when thepoppet valve 2 is closed. Thevalve cover 7 thus does not move while the piston is in a combustion stroke. As a result, thevalve cover 7 is hard to seize up. - In
FIG. 1 , theupper face 8 of thevalve cover 7 and thebottom face 3 of thepoppet valve 2 are in intimate contact with each other, and a boundary of thevalve cover 7 andpoppet valve 2 is drawn by a solid line. InFIG. 1 , two lead lines refer the solid line showing the intimate contact. The upper lead line is forreference numeral 8 and the lower one is forreference numeral 3. The solid line represents both the upper face of thevalve cover 7 and thebottom face 3 of thepoppet valve 2. Therefore, the two lead lines are drawn in the opposite direction with each other. - When the
upper face 8 of thevalve cover 7 and thebottom face 3 of thepoppet valve 2 are in intimate contact with each other, combustion gas does not break into the boundary between thevalve cover 7 and thebottom face 3 of thepoppet valve 2. It is preferable that theupper face 8 of thevalve cover 7 and the bottom face of thepoppet valve 2 have the same size. In this case, theupper face 8 of thevalve cover 7 is not subjected to combustion gas pressure. If theupper face 8 of thevalve cover 7 is larger than thebottom face 3 of thepoppet valve 2, theupper face 8 of thevalve cover 7 is subjected to the combustion gas pressure. - The
poppet valve 2 is closed during a compression stroke of thepiston 26. Thevalve cover 7 is located with abutting thebottom face 3 of thepoppet valve 2. The upper part of thevalve cover 7 occupies the most space of the extended part of thecombustion chamber 27 outside themain cylinder 1, which would face with thebottom face 3 of thepoppet valve 2 if thevalve cover 7 were not provided. As a result, the volume of thecombustion chamber 27 reduces by the volume of the upper part of thevalve cover 7 which protrudes into thecombustion chamber 27. Compared to the engine ofpatent document 1, compression ratio of the combustion chamber 17 becomes high. Therefore, the first object is achieved by this engine. - Regarding
FIG. 2 , when thecam 30 lifts thepoppet valve 2, thevalve cover 7 moves along with thepoppet valve 2. When thepoppet valve 2 lifts to the maximum, the most part of thevalve cover 7 positions inside thesub cylinder 4. When thepoppet valve 2 is open, thecombustion chamber 27 facing with the upper face of the piston communicates to outside of the engine. - In the first embodiment, the
poppet valve 2 is provided on the wall of the first part extended outside themain cylinder 1 of thecombustion chamber 27. Further, the total number of the overhead valves and poppet valve is not less than three. Therefore in the engine of first embodiment, the total area of the intake and exhaust valves increases compared to the conventional art which does not have a poppet valve outside a main cylinder. In the first embodiment, theoverhead valves patent document 3. - Therefore, when the engine of the first embodiment rotates at high speed, efficiency of intake and exhaust increases compared to the conventional art. This advantage is not disclosed in
patent documents - It is not disclosed in
patent document 3 to increase the area of intake or exhaust side valves. - It is disclosed in
patent document 2 to provide both overhead valve and sliding valve. However, this feature is different from the first embodiment. - Second to fifth embodiments are modifications of the first embodiment. The first object is achieved in these embodiments.
- For these embodiments, only the difference from the first embodiment will be described.
- The second embodiment will be described.
- In
FIG. 4 , thesub cylinder 4 is provided in thecylinder head 5. In this case, the gas path contacting with thepoppet valve 2 is provided in the cylinder block. Thepoppet valve 2 provided outside the cylinder is a side valve. - The third embodiment will be described.
- In
FIG. 5 , a pneumatic unit,hydraulic unit 19, electromagnetic unit or electric unit is employed in place of thespring 12. These units bias thevalve cover 7 so that theupper face 8 presses the bottom face of thepoppet valve 2. These units and thethird spring 12 are to bias thevalve cover 7 toward thevalve sheet 16. - In
FIG. 5 , thecompression ring 9 is subject to the pressure of the combustion gas so that the valve cover is pushed downwards. The valve cover and the bottom face of the poppet valve are not separated from each other by the pressing force. - The above-described units including the
hydraulic unit 19 bias the valve cover toward thevalve sheet 16 of thepoppet valve 2 with a force not less than this pressing force. - The fourth embodiment will be described.
- In
FIG. 6 , thepoppet valve 2 andvalve cover 7 are integrally formed. - In
FIG. 6 , a dashed dotted line shows a phantom joint face between thepoppet valve 2 andvalve cover 7. Actually, the joint face shown by the dashed-dotted line does not exist. - In
FIG. 6 , when thethird spring 12 to push thevalve cover 7 is not provided, thesecond spring 31 abutting the stem of thepoppet valve 2 functions as a replacement of thethird spring 12. Thesecond spring 31 pulls thepoppet valve 2. Thespring 12 may be thus omitted. - Conversely, when the
third spring 12 is provided, thesecond spring 31 abutting the stem ofpoppet valve 2 may be omitted. - The fifth embodiment will be described.
- In
FIG. 7 , a ring groove for thecompression ring 9 is provided on an inner wall of thesub cylinder 4. Thecompression ring 9 is disposed onto the ring groove. - In order that the
compression ring 9 seals the combustion gas, thecompression ring 9 is wedged between the cylindrical side face of thevalve cover 7 and the inner wall of thesub cylinder 4. A ring groove is not provided on the cylindrical side face of thevalve cover 7. Therefore in this engine, the force of the combustion gas given to thecompression ring 9 does not push thevalve cover 7 downward. Therefore in the engine shown inFIG. 7 , a weaker spring may be employed than the spring of the engine shown inFIG. 1 . - The following sixth to tenth embodiments show additional features to the first to fifth embodiments. The sixth to tenth embodiments are to further modify the first to fifth embodiments.
- The sixth to tenth embodiments are not disclosed in
patent documents - The sixth and eighth to tenth embodiments are not disclosed in
patent document 2. - The sixth embodiment will be described with reference to
FIGS. 8 and 9 . - The sixth embodiment is included in the second aspect.
- The
end 10 of thesub cylinder 4 is disposed at a position adjacent to thesecond valve sheet 16 of thepoppet valve 2. The part adjacent to thepoppet valve 2 of thesub cylinder 4 may be formed integrally with the part facing with thecompression ring 9 of thesub cylinder 4, or may be formed as a part of the cylinder head. When thepoppet valve 2 is open, the valve head of thepoppet valve 2 is located inside thesub cylinder 4. - The whole circumference of the cylindrical side face of the
valve cover 7 adjacent to thepoppet valve 2 is sectioned into two half circumferences by a dashed-fourdotted line 38 which is perpendicular to a dashed-three dottedline 39 connecting thecentral axis 37 of themain cylinder 1 and the central axis of thesub cylinder 4 intersecting at the central axis of thesub cylinder 4. - The two half circumferences are referred to as a first half circumference which is close to the
central axis 37 of themain cylinder 1 and a second half circumference which is away from thecentral axis 37 of themain cylinder 1. - The cylindrical side face of the
valve cover 7 adjacent to thepoppet valve 2 is sectioned into two half surrounding faces. The two half surrounding faces are a firsthalf surrounding face 40 having the first half circumference and a secondhalf surrounding face 35 having the second half circumference. - A part adjacent to the second valve sheet of the
sub cylinder 4 faces with the secondhalf surrounding face 35. The part is drawn as the sub cylinder referred byreference numeral 4 inFIG. 9 . - A fixed wall, which is located outside the combustion chamber extended outside the
main cylinder 1, is provided adjacent to the inner wall facing with the secondhalf surrounding face 35 of thesub cylinder 4. - When the part adjacent to the
poppet valve 2 of thesub cylinder 4 is formed integrally with a part facing with thecompression ring 9 of thesub cylinder 4, the fixed wall located outside the combustion chamber extended outside themain cylinder 1 is constituted by a fixed wall which is adjacent to theouter face 36 facing with the secondhalf surrounding face 35 of thesub cylinder 4 and thesub cylinder 4 which faces with the secondhalf surrounding face 35. - An
opening 18 of thesub cylinder 4 is provided in the vicinity of the oneend 10 of thesub cylinder 4. - A
first gas path 11 is provided between thesecond valve sheet 16 of thepoppet valve 2 and outside of the engine. - A
second gas path 21 is provided which communicates the space inside themain cylinder 1 and thefirst gas path 11 in a short distance when thepoppet valve 2 is open. Theopening 18 constitutes thesecond gas path 21. InFIG. 9 , theopening 18 is shown by a dashed-two dotted line. - The
opening 18 faces with the firsthalf surrounding face 40. - The
second gas path 21 is included in the combustion chamber surrounded by the second part. - A plurality of the combinations of the
valve cover 7,sub cylinder 4 and theopening 18 may be provided in the second part which extends outside themain cylinder 1. - In the sixth embodiment, the volume of the combustion chamber extended outside the main cylinder is decreased compared to the engines disclosed in
patent documents - The cylindrical side face of the
valve cover 7 is subject to the heat of the combustion gas in a part of its upper part during combustion strokes and expansion strokes. - A part adjacent to the
poppet valve 2 of the cylindrical side face of thevalve cover 7 is subject to the pressure of the combustion gas in a direction from the central axis of themain cylinder 1 to the central axis of thesub cylinder 4 during combustion strokes and expansion strokes. When the part adjacent to thepoppet valve 2 of the cylindrical side face of thevalve cover 7 is divided into two sections, the secondhalf surrounding face 35 is pressed to and contacts closely with the part of thesub cylinder 4 comprising theouter face 36. The part comprising theouter face 36 of thesub cylinder 4 faces with the secondhalf surrounding face 35. The combustion gas does not flow in between the contacted two faces. The heat of the combustion gas does not flow into the contacted two faces. - Consequently in the sixth embodiment, the area which is subjected to the heat of the combustion gas in the cylindrical side face of the
valve cover 7 is reduced compared to the engine disclosed inpatent document 3, and the thermal loss of this engine is thus reduced. The larger the area in close contact is, the lower the temperature of the cylindrical side face becomes. Therefore, the fuel efficiency is improved and the resistance to knocking is also improved compared to the engine disclosed inpatent document 3. - The seventh embodiment will be described.
- The seventh embodiment is included in the third aspect.
- The problems relating to a balance of conversion efficiency improvement and torque enhancement is described in the description of the related art.
- This problem can be solved by the following feature. The engines of the first to sixth embodiments are further configured such that the length of the piston stroke is not shorter than the diameter of the piston. That is, the length of the piston stroke is approximately same as or longer than the diameter of the main piston in these engines.
- By this feature, the conversion efficiency of combustion gas is improved compared to short stroke engines. Also, decrease of intake efficiency which occurs in long stroke engines rotating at high speed is improved. As a result, it becomes possible to strike improvement of conversion efficiency and increase of torque at high speed in balance. The third object is thus achieved.
- The eighth embodiment will be described with reference to
FIG. 10 . - The part adjacent to the
poppet valve 2 of thevalve cover 7 is heated by the combustion gas in combustion strokes. In the case of a spark-ignition engine, knocking is caused by a high temperature part in a combustion chamber. In the case of a piston engine, a filling rate of intake decreases due to a high temperature part in a combustion chamber. - In order to solve these problems, a
spray valve 41 is further provided to the engines of the first to seventh embodiments. Thespray valve 41 sprays oil to the back face of the part adjacent to thepoppet valve 2 of thevalve cover 7. Further, thespring 12 is provided with abutting the back face. Thus, the temperature of the part adjacent to thepoppet valve 2 of thevalve cover 7 becomes low, and knocking occurs less. Then, it becomes possible to configure the compression ratio higher, and the heat efficiency is thus improved. As a result, the third object is achieved. - Further, the filling rate of intake does not decrease.
- The ninth embodiment will be described.
- The following feature of the engine shown in
FIG. 11 may be added to any embodiments except the fourth embodiment. - The face abutting the
poppet valve 2 of thevalve cover 7 is a convex curve, and the face contacting with thevalve cover 7 of thepoppet valve 2 is a concave curve. These two faces have a same curvature. - In the engine shown in
FIG. 1 , if the pressure in the combustion chamber increases sharply, the part adjacent to the poppet valve of thevalve cover 7 is pressed in a direction toward the opposite side of thepiston 26. The part adjacent to thepoppet valve 2 of thevalve cover 7 may be thus deformed. Thebottom 3 of thepoppet valve 2 is not deformed. On the other hand, a gap does not formed between the two curved faces in the engine shown inFIG. 11 . A solid line shows the state that the two faces closely contacted with each other. Even if the pressure in the combustion chamber increases sharply, the two faces shown inFIG. 11 do not separate from each other. - The tenth embodiment will be described.
- In the engine shown in
FIG. 7 , when oil is supplied to the inner wall of thesub cylinder 4, the oil penetrates into the gap between the cylindrical side face of thevalve cover 7 and the inner wall of thesub cylinder 4 by capillarity and movement of thevalve cover 7. The oil penetrated into the gap is sucked into the combustion chamber during intake strokes. As a result, oil consumption increases. - On the other hand, when an
oil ring 22 is provided on the cylindrical side face of thevalve cover 7 as shown inFIG. 12 , the oil consumption can be controlled. However, thecompression ring 9 provided on the inner wall of the sub cylinder does not move. Accordingly, thecompression ring 9 does not transfer the oil. Therefore, in the case shown inFIG. 12 , thecompression ring 9 provided at the closer side to the combustion chamber lacks its lubrication. - This problem is solved by adding the following feature.
- As shown in
FIG. 13 , theupper compression ring 23 is provided on the inner wall of the sub cylinder at the closer side to thecombustion chamber 27, and thelower compression ring 24 is provided on the cylindrical side face of thevalve cover 7. Theupper compression ring 23 is provided between thelower compression ring 24 andcombustion chamber 27. When thepoppet valve 2 is closed, the upper end of thelower compression ring 24 is located adjacent to the lower end of theupper compression ring 23. Thelower compression ring 24 is provided between theoil ring 22 and theupper compression ring 23. Theoil ring 22 is provided on the cylindrical side face of the member. - When the
valve cover 7 moves, thelower compression ring 24 also moves. The movinglower compression ring 24 transfers the residual oil which is not removed by the oil ring to the lower end of theupper compression ring 23. Theupper compression ring 23 is thus lubricated. - A spray hole of oil is provided between the position of the
lower compression ring 24 when the cam shifts thevalve cover 7 at the maximum and the position of theoil ring 22 when thepoppet valve 2 is closed. Thus, the amount of oil which thelower compression ring 24 transfers increases.
Claims (37)
1. A piston engine with a member to cover a bottom face of a valve head of a poppet valve, comprising:
a combustion chamber defined between a piston and a cylinder head, in which the combustion chamber further extends outside a main cylinder;
an inner wall of the combustion chamber, comprising a first part and a second part, the first part being a part facing with an upper face of the piston provided inside the main cylinder, the second part being an extended part outside the main cylinder
a sub cylinder provided outside the main cylinder;
the poppet valve provided on the second part, the poppet valve being provided with a second drive unit to drive a stem of the poppet valve, in which a gas passes through a gap between the poppet valve and a second valve sheet of the poppet valve when the poppet valve is open;
the member to cover the bottom face of the valve head of the poppet valve, in which the member reciprocates in the sub cylinder and comprises a cylindrical side face, in which the valve head is located between the second valve sheet and the member;
a means to make the second valve sheet, the valve head and the member contact closely one another, in which the second drive unit and the means drive the poppet valve and the member integrally, in which the member abuts the bottom face of the poppet valve;
a compression ring provided at a position wedged between an inner wall of the sub cylinder and the cylindrical side face of the member; and
an overhead valve provided on the first part, in which a gas passes through the a gap between the overhead valve and a first valve sheet of the overhead valve when the overhead valve is open, in which the overhead valve is provided with a first spring and a first drive unit,
wherein a combination of the overhead valve and the poppet valve includes at least one intake valve and one exhaust valve, and
the total number of the overhead valve and the poppet valve is not less than 3.
2. A piston engine with a member to cover a bottom face of a valve head of a poppet valve, comprising:
a combustion chamber defined between a piston and a cylinder head, in which the combustion chamber further extends outside a main cylinder;
an inner wall of the combustion chamber, comprising a first part and a second part, the first part being a part facing with an upper face of the piston provided inside the main cylinder, the second part being an extended part outside the main cylinder
a sub cylinder provided outside the main cylinder;
the poppet valve provided on the second part, the poppet valve being provided with a second drive unit to drive a stem of the poppet valve;
the member to cover the bottom face of the valve head of the poppet valve, in which the member reciprocates in the sub cylinder and comprises a cylindrical side face, in which the valve head is located between a second valve sheet of the poppet valve and the member;
a means to make the second valve sheet, the valve head and the member contact closely one another, in which the second drive unit and the means drive the poppet valve and the member integrally, in which the member abuts the bottom face of the poppet valve;
a compression ring provided at a position wedged between an inner wall of the sub cylinder and the cylindrical side face of the member; and
an overhead valve provided on the first part, in which a gas passes through the a gap between the overhead valve and a first valve sheet of the overhead valve when the overhead valve is open, in which the overhead valve is provided with a first spring and a first drive unit,
wherein a combination of the overhead valve and the poppet valve includes at least one intake valve and one exhaust valve,
a plurality of the poppet valve are provided on the second part, all of the plurality of poppet valves provided on the second part being exhaust poppet valves, and
at least one of the overhead valve provided on the first part is an intake valve.
3. The piston engine with the member according to claim 1 ,
wherein a plurality of the poppet valve is provided on the second part, all of the plurality of poppet valves provided on the second part being intake poppet valves, and
at least one of the overhead valve provided on the first part is an exhaust valve.
4. A piston engine with a member to cover a bottom face of a valve head of a poppet valve, comprising:
a combustion chamber defined between a piston and a cylinder head, in which the combustion chamber further extends outside a main cylinder;
an inner wall of the combustion chamber, comprising a first part and a second part, the first part being a part facing with an upper face of the piston provided inside the main cylinder, the second part being an extended part outside the main cylinder;
a sub cylinder provided outside the main cylinder;
the poppet valve provided on the second part, the poppet valve being provided with a second drive unit to drive a stem of the poppet valve, in which a gas passes through a gap between the poppet valve and a second valve sheet of the poppet valve when the poppet valve is open;
the member to cover the bottom face of the valve head of the poppet valve, in which the member reciprocates in the sub cylinder and comprises a cylindrical side face, in which the valve head is located between the second valve sheet of the poppet valve and the member;
a means to make the second valve sheet, the valve head and the member contact closely one another, in which the second drive unit and the means drive the poppet valve and the member integrally, in which the member abuts the bottom face of the poppet valve;
a compression ring provided at a position between an inner wall of the sub cylinder and the cylindrical side face of the member; and
at least one or more overhead valve provided on the first part, all of the overhead valve provided on the first part being an intake overhead valve, in which the overhead valve is provided with a first spring and a first drive unit,
wherein the total number of the overhead valve and the poppet valve is not less than 3, and
an exhaust poppet valve is provided on the second part.
5. The piston engine with the member according to claim 1 ,
wherein one end of the sub cylinder is located adjacent to the second valve sheet,
a whole circumference of the cylindrical side face of the member adjacent to the poppet valve is sectioned into two half circumferences by a line which is perpendicular to a line connecting a central axis of the main cylinder and a central axis of the sub cylinder intersecting at the central axis of the sub cylinder,
the two half circumferences are referred to as a first half circumference which is close to the central axis of the main cylinder and a second half circumference which is away from the central axis of the main cylinder,
the cylindrical side face of the member adjacent to the poppet valve is sectioned into two half surrounding faces,
the two half surrounding faces are a first half surrounding face having the first half circumference and a second half surrounding face having the second half circumference,
a part adjacent to the second valve sheet of the sub cylinder faces with the second half surrounding face,
a fixed wall, which is located outside the combustion chamber extended outside the main cylinder, is formed adjacent to an inner wall facing with the second half surrounding face of the sub cylinder,
the sub cylinder comprises a opening in a vicinity of the one end of the sub cylinder,
the piston engine further comprises:
a first gas path provided between the second valve sheet and outside of the engine; and
a second gas path which communicates an inner space of the main cylinder and the first gas path in a short distance when the poppet valve is open, the second gas path including the opening, and
the opening faces with the first half surrounding face.
6. The piston engine with the member according to claim 2 ,
wherein one end of the sub cylinder is located adjacent to the second valve sheet,
a whole circumference of the cylindrical side face of the member adjacent to the poppet valve is sectioned into two half circumferences by a line which is perpendicular to a line connecting a central axis of the main cylinder and a central axis of the sub cylinder intersecting at the central axis of the sub cylinder,
the two half circumferences are referred to as a first half circumference which is close to the central axis of the main cylinder and a second half circumference which is away from the central axis of the main cylinder,
the cylindrical side face of the member adjacent to the poppet valve is sectioned into two half surrounding faces,
the two half surrounding faces are a first half surrounding face having the first half circumference and a second half surrounding face having the second half circumference,
a part adjacent to the second valve sheet of the sub cylinder faces with the second half surrounding face,
a fixed wall, which is located outside the combustion chamber extended outside the main cylinder, is formed adjacent to an inner wall facing with the second half surrounding face of the sub cylinder,
the sub cylinder comprises a opening in a vicinity of the one end of the sub cylinder,
the piston engine further comprises:
a first gas path provided between the second valve sheet and outside of the engine; and
a second gas path which communicates an inner space of the main cylinder and the first gas path in a short distance when the poppet valve is open, the second gas path including the opening, and
the opening faces with the first half surrounding face.
7. The piston engine with the member according to claim 3 ,
wherein one end of the sub cylinder is located adjacent to the second valve sheet,
a whole circumference of the cylindrical side face of the member adjacent to the poppet valve is sectioned into two half circumferences by a line which is perpendicular to a line connecting a central axis of the main cylinder and a central axis of the sub cylinder intersecting at the central axis of the sub cylinder,
the two half circumferences are referred to as a first half circumference which is close to the central axis of the main cylinder and a second half circumference which is away from the central axis of the main cylinder,
the cylindrical side face of the member adjacent to the poppet valve is sectioned into two half surrounding faces,
the two half surrounding faces are a first half surrounding face having the first half circumference and a second half surrounding face having the second half circumference,
a part adjacent to the second valve sheet of the sub cylinder faces with the second half surrounding face,
a fixed wall, which is located outside the combustion chamber extended outside the main cylinder, is formed adjacent to an inner wall facing with the second half surrounding face of the sub cylinder,
the sub cylinder comprises a opening in a vicinity of the one end of the sub cylinder,
the piston engine further comprises:
a first gas path provided between the second valve sheet and outside of the engine; and
a second gas path which communicates an inner space of the main cylinder and the first gas path in a short distance when the poppet valve is open, the second gas path including the opening, and
the opening faces with the first half surrounding face.
8. The piston engine with the member according to claim 4 ,
wherein one end of the sub cylinder is located adjacent to the second valve sheet,
a whole circumference of the cylindrical side face of the member adjacent to the poppet valve is sectioned into two half circumferences by a line which is perpendicular to a line connecting a central axis of the main cylinder and a central axis of the sub cylinder intersecting at the central axis of the sub cylinder,
the two half circumferences are referred to as a first half circumference which is close to the central axis of the main cylinder and a second half circumference which is away from the central axis of the main cylinder,
the cylindrical side face of the member adjacent to the poppet valve is sectioned into two half surrounding faces,
the two half surrounding faces are a first half surrounding face having the first half circumference and a second half surrounding face having the second half circumference,
a part adjacent to the second valve sheet of the sub cylinder faces with the second half surrounding face,
a fixed wall, which is located outside the combustion chamber extended outside the main cylinder, is formed adjacent to an inner wall facing with the second half surrounding face of the sub cylinder,
the sub cylinder comprises a opening in a vicinity of the one end of the sub cylinder,
the piston engine further comprises:
a first gas path provided between the second valve sheet and outside of the engine; and
a second gas path which communicates an inner space of the main cylinder and the first gas path in a short distance when the poppet valve is open, the second gas path including the opening, and
the opening faces with the first half surrounding face.
9. The piston engine with the member according to claim 1 , wherein a stroke length of the piston is not shorter than a diameter of the piston.
10. The piston engine with the member according to claim 2 , wherein a stroke length of the piston is not shorter than a diameter of the piston.
11. The piston engine with the member according to claim 3 , wherein a stroke length of the piston is not shorter than a diameter of the piston.
12. The piston engine with the member according to claim 4 , wherein a stroke length of the piston is not shorter than a diameter of the piston.
13. The piston engine with the member according to claim 5 , wherein a stroke length of the piston is not shorter than a diameter of the piston.
14. The piston engine with the member according to claim 6 , wherein a stroke length of the piston is not shorter than a diameter of the piston.
15. The piston engine with the member according to claim 7 , wherein a stroke length of the piston is not shorter than a diameter of the piston.
16. The piston engine with the member according to claim 8 , wherein a stroke length of the piston is not shorter than a diameter of the piston.
17. The piston engine with the member according to claim 1 , further comprising:
a spray valve to spray oil toward a back face of a part adjacent to the poppet valve of the member; and
a third spring abutting the back face.
18. The piston engine with the member according to claim 2 , further comprising:
a spray valve to spray oil toward a back face of a part adjacent to the poppet valve of the member; and
a third spring abutting the back face.
19. The piston engine with the member according to claim 3 , further comprising:
a spray valve to spray oil toward a back face of a part adjacent to the poppet valve of the member; and
a third spring abutting the back face.
20. The piston engine with the member according to claim 4 , further comprising:
a spray valve to spray oil toward a back face of a part adjacent to the poppet valve of the member; and
a third spring abutting the back face.
21. The piston engine with the member according to claim 5 , further comprising:
a spray valve to spray oil toward a back face of a part adjacent to the poppet valve of the member; and
a third spring abutting the back face.
22. The piston engine with the member according to claim 6 , further comprising:
a spray valve to spray oil toward a back face of a part adjacent to the poppet valve of the member; and
a third spring abutting the back face.
23. The piston engine with the member according to claim 7 , further comprising:
a spray valve to spray oil toward a back face of a part adjacent to the poppet valve of the member; and
a third spring abutting the back face.
24. The piston engine with the member according to claim 8 , further comprising:
a spray valve to spray oil toward a back face of a part adjacent to the poppet valve of the member; and
a third spring abutting the back face.
25. The piston engine with the member according to claim 1 ,
wherein the sub cylinder comprises a groove for the compression ring, and the compression ring is disposed on the groove.
26. The piston engine with the member according to claim 2 ,
wherein the sub cylinder comprises a groove for the compression ring, and the compression ring is disposed on the groove.
27. The piston engine according to claim 4 ,
wherein the sub cylinder comprises a groove for the compression ring, and the compression ring is disposed on the groove.
28. The piston engine with the member according to claim 1 ,
wherein a face contacting with the poppet valve of the member is a convex curve, a face contacting with the member of the poppet valve is a concave curve, and the two faces have a same curvature,
the member and the poppet valve are not integrally formed, and
the member and the valve head of the poppet valve contact with each other.
29. The piston engine with the member according to claim 5 ,
wherein a face contacting with the poppet valve of the member is a convex curve, a face contacting with the member of the poppet valve is a concave curve, and the two faces have a same curvature,
the member and the poppet valve are not integrally formed, and
the member and the valve head of the poppet valve contact with each other.
30. The piston engine with the member according to claim 6 wherein the compression ring comprises:
an upper compression ring provided on an inner wall of the sub cylinder near the combustion chamber; and
a lower compression ring provided on the cylindrical side wall of the member,
wherein the upper compression ring is provided between the lower compression ring and the combustion chamber,
an upper end of the lower compression ring is located adjacent to a lower end of the upper compression ring when the poppet valve is closed,
the piston engine further comprises a oil ring provided on the cylindrical side face of the member, and
the lower compression ring is provided between the oil ring and the upper compression ring.
31. The piston engine with the member according to claim 7 wherein the compression ring comprises:
an upper compression ring provided on an inner wall of the sub cylinder near the combustion chamber; and
a lower compression ring provided on the cylindrical side wall of the member,
wherein the upper compression ring is provided between the lower compression ring and the combustion chamber,
an upper end of the lower compression ring is located adjacent to a lower end of the upper compression ring when the poppet valve is closed,
the piston engine further comprises a oil ring provided on the cylindrical side face of the member, and
the lower compression ring is provided between the oil ring and the upper compression ring.
32. The piston engine with the member according to claim 8 wherein the compression ring comprises:
an upper compression ring provided on an inner wall of the sub cylinder near the combustion chamber; and
a lower compression ring provided on the cylindrical side wall of the member,
wherein the upper compression ring is provided between the lower compression ring and the combustion chamber,
an upper end of the lower compression ring is located adjacent to a lower end of the upper compression ring when the poppet valve is closed,
the piston engine further comprises a oil ring provided on the cylindrical side face of the member, and
the lower compression ring is provided between the oil ring and the upper compression ring.
33. The piston engine with the member according to claims 1 ,
wherein the means is a device to bias the member toward the second valve sheet,
the device to bias the member toward the second valve sheet is a third spring abutting the member, and
the third spring does not face with a space of the combustion chamber.
34. The piston engine with the member according to claims 5 ,
wherein the means is a device to bias the member toward the second valve sheet,
the device to bias the member toward the second valve sheet is a third spring abutting the member, and
the third spring does not face with a space of the combustion chamber.
35. The piston engine with the member according to claims 6 ,
wherein the means is a device to bias the member toward the second valve sheet,
the device to bias the member toward the second valve sheet is a third spring abutting the member, and
the third spring does not face with a space of the combustion chamber.
36. The piston engine with the member according to claims 7 ,
wherein the means is a device to bias the member toward the second valve sheet,
the device to bias the member toward the second valve sheet is a third spring abutting the member, and
the third spring does not face with a space of the combustion chamber.
37. The piston engine with the member according to claims 8 ,
wherein the means is a device to bias the member toward the second valve sheet,
the device to bias the member toward the second valve sheet is a third spring abutting the member, and
the third spring does not face with a space of the combustion chamber.
Applications Claiming Priority (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2009010427 | 2009-01-20 | ||
JPA2009-010427 | 2009-01-20 | ||
JPA2009-241923 | 2009-10-21 | ||
JP2009241923A JP4558090B1 (en) | 2009-01-20 | 2009-10-21 | Piston engine with parts that cover the bottom of the umbrella part of the valve |
Publications (1)
Publication Number | Publication Date |
---|---|
US20100180851A1 true US20100180851A1 (en) | 2010-07-22 |
Family
ID=42335948
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US12/688,885 Abandoned US20100180851A1 (en) | 2009-01-20 | 2010-01-17 | Piston engine comprising member to cover bottom face of valve head of poppet valve |
Country Status (1)
Country | Link |
---|---|
US (1) | US20100180851A1 (en) |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR2980517A1 (en) * | 2011-09-23 | 2013-03-29 | Peugeot Citroen Automobiles Sa | Internal combustion engine for car, has valve head allowing sealing between additional chamber and combustion chamber by valve body that seals opening of additional chamber for allowing fluid connection with combustion chamber |
FR2980821A1 (en) * | 2011-09-30 | 2013-04-05 | Peugeot Citroen Automobiles Sa | Internal combustion engine e.g. direct injection diesel engine, for car, has combustion chamber that is in fluid connection with each conduit via passages connecting chamber to each conduit either directly or via auxiliary chambers |
CN111946483A (en) * | 2020-07-15 | 2020-11-17 | 东风汽车集团有限公司 | Cylinder cover combustion chamber structure and automobile engine |
Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US1510651A (en) * | 1924-10-07 | Supercharging internal-combustion-engine valve mechanism | ||
US2260982A (en) * | 1939-03-21 | 1941-10-28 | Walker Brooks | Internal combustion engine |
US4321904A (en) * | 1978-10-11 | 1982-03-30 | Bristol Robert D | Internal combustion engine with auxiliary combustion chamber |
US20030226537A1 (en) * | 2002-06-07 | 2003-12-11 | Josef Schaich | Ring valve for 4-stroke piston engine |
US20070204814A1 (en) * | 2006-03-01 | 2007-09-06 | The Scuderi Group, Llc | Split-cycle engine with disc valve |
-
2010
- 2010-01-17 US US12/688,885 patent/US20100180851A1/en not_active Abandoned
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US1510651A (en) * | 1924-10-07 | Supercharging internal-combustion-engine valve mechanism | ||
US2260982A (en) * | 1939-03-21 | 1941-10-28 | Walker Brooks | Internal combustion engine |
US4321904A (en) * | 1978-10-11 | 1982-03-30 | Bristol Robert D | Internal combustion engine with auxiliary combustion chamber |
US20030226537A1 (en) * | 2002-06-07 | 2003-12-11 | Josef Schaich | Ring valve for 4-stroke piston engine |
US20070204814A1 (en) * | 2006-03-01 | 2007-09-06 | The Scuderi Group, Llc | Split-cycle engine with disc valve |
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
FR2980517A1 (en) * | 2011-09-23 | 2013-03-29 | Peugeot Citroen Automobiles Sa | Internal combustion engine for car, has valve head allowing sealing between additional chamber and combustion chamber by valve body that seals opening of additional chamber for allowing fluid connection with combustion chamber |
FR2980821A1 (en) * | 2011-09-30 | 2013-04-05 | Peugeot Citroen Automobiles Sa | Internal combustion engine e.g. direct injection diesel engine, for car, has combustion chamber that is in fluid connection with each conduit via passages connecting chamber to each conduit either directly or via auxiliary chambers |
CN111946483A (en) * | 2020-07-15 | 2020-11-17 | 东风汽车集团有限公司 | Cylinder cover combustion chamber structure and automobile engine |
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Legal Events
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STCB | Information on status: application discontinuation |
Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION |