Piston engine comprising member to cover bottom face of valve head of poppet valve

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.

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.