Articulated, spring-controlled intake poppet valve
United States Patent 11 1 1111 3,875,921  
 Deboy et a1. [45] A 8, 1975 [54] ARTICULATED, SPRING-CONTROLLED 1,542,617 6/1925 Guy et a1 123/81 B INTAKE popp VALVE 2,622,574 12/1952 Butterworth 123/9024 3,299,869 l/l967 Sicklesteel 123/188 S X [75] Inventors 3igj$$ FOREIGN PATENTS OR APPLICATIONS Stoughton, Rochester of 1,105,147 11/1955 FIHIICE 251/298 1,236,581 6/1960 France 251/303 1 Assignee= General Motors po a on, 17,756 12/1900 United Kingdom 251/298 Detroit, Mich. [221 Filed: Oct 23, 1973 Primary Examiner-Charles .1. Myhre Assistant Examiner-W. Rutledge, Jr. 1 1 PP NW 4081844 Attorney, Agent, or Firm-Arthur N. Krein 52 us. c1.. 123/188 AP; 123/188 R; 123/188 sc; 1571 ABSTRACT 251/303 An articulated, spring-controlled intake poppet valve [51] Int. Cl. F011 3/10; F011 3/20 for use in the intake port of a four-stroke cycle, recip- [581 Field of Search 123/188 R, 188 VA, 188 S, rocating internal combustion engine, the poppet valve 123/188 AF, 188 SB, 188 SC, 188 AP, including a valve head and a separate valve actuating 90.28, 90,29, 90,3, 81 13; 251/298, 303 stem pivotally interconnected to each other, the valve head being normally held closed by a coiled spring 10- [56] References Cited cated inside the intake port with one end of the spring UNITED STATES PATENTS secured to the valve head and the other end thereof to 1.397.585 11/1921 James 123/9027 x the cylmder head 1,419,988 6/1922 Rohrer 251/303 X 6 Claims, 2 Drawing Figures ARTICULATED, SPRING-CONTROLLED INTAKE POPPET VALVE This invention relates to valves for reciprocating internal combustion engines and, in particular, to an articulated, spring-controlled intake poppet valve struc ture to be used in the intake port of an internal combustion engine.  
  Intake or induction valves for internal combustion engines are normally of the poppet valve type in which the valve has an annular head adapted to seat against a valve seat in the cylinder head of the engine to control the flow of induction fluid from the intake manifold through an inlet port, defined in part by the valve seat, to the cylinder of the engine during the induction cycle for that cylinder of the engine and, an integral stem extending from the head of the valve concentric therewith, this stem being reciprocally journalled in the cylinder head of the engine with one end of the stem extending from the cylinder head for engagement by suitable means, such as a rocker arm or cam. to effect reciprocating movement of the valve head in a direction in line with the common axis of the stem and head of such a valve. The head of the poppet valve is provided with an annular seating portion adapted to seat against an annular bevelled valve seat provided in the inlet or intake port in the cylinder head.  
  In such a conventional poppet valve, when the head is unseated from the valve seat, a uniform annular flow area is provided between the valve head and the inlet port for the flow of induction fluid into the cylinder or combustion chamber of the engine. With such an arrangement, induction fluid flow is substantially uniform around the head of the valve and, accordingly, depending on the location of the inlet port relative to the longitudinal axis of the cylinder, there is little or no swirling motion of the induction fluid entering the cylinder around the longitudinal axis of the cylinder.  
  Because of this, various means have been used in the prior art to promote swirl of the induction fluid on entry into the combustion chamber, such as by the use of a shrouded valve or a swirl port. For example, by providing the outer surface of the valve guide in the inlet port with suitable shaped ribs or vanes, induction fluid entering the cylinder from this port is given a direction of flow which, in general, is in the desired direction of induction fluid flow rotation around the axis of the cylinder. However, it has been found that whether a shrouded valve or a swirl port is used to introduce swirl, the use of such a swirl inducing device will effect a reduction in the volumetric efficiency of the engine. Furthermore, the use of either a shrouded valve or a swirl port is not readily adaptable for use in a split manifold type engine.  
  Accordingly, the principal object of this invention is to provide a poppet valve structure whereby the head of the poppet valve can be moved axially and pivoted relative to an annular valve seat in a direction to more advantageously direct the flow of induction fluid into the combustion chamber of an internal combustion engine and result in fluid motions advantageous to combustion.  
  Another object of this invention is to provide an intake valve structure for use in the intake port of an internal combustion engine which, upon actuation, can effect strong combustion chamber swirl generation of induction fluid.  
  A still further object of this invention is to provide a poppet valve and intake port structure having an improved intake valve-port flow coefficient.  
 These and other objects of the invention are attained 5 by an articulated, spring-controlled intake poppet valve and intake port structure in which a valve head and valve stem are separate pieces pivotally interconnected together whereby the valve head can pivot relative to the longitudinal axis of the stem. The valve head is held closed relative to an annular valve seat forming a part of the inlet port in the cylinder head of an engine by means of a coiled spring which is located inside the intake port and has one end attached to the cylinder head and the other end attached to the valve head, the spring functioning to maintain contact between the valve head and stem during actuation of the poppet valve and helps to determine the valve head trajectory during stem movement.  
  For a better understanding of the invention, as well as other objects and further features thereof, reference is had to the following detailed description of the invention to be read in connection with the accompanying drawings, wherein:  
  FIG. 1 is a sectional view of a portion of an internal combustion engine having an articulated, springcontrolled intake poppet valve in accordance with the invention, positioned to control the flow of induction fluid into the combustion chamber of the engine, the valve being shown in its open position; and,  
  FIG. 2 is an enlarged view of a portion of the structure of FIG. 1 showing the subject intake poppet valve in its closed position.  
  Referring now to the drawings, there is illustrated a portion of an internal combustion engine having an engine cylinder block with a cylinder bore 12 therein reciprocally receiving a piston 14 to define a combustion chamber, the cylinder bore being partly closed at one end by a cylinder head 16 suitably secured to the cylinder block. The cylinder head 16 is provided with an induction passage 18 terminating at an intake or inlet port 20. Inlet port 20 presents an annular valve seat 22 which, as is well known, is chamfered or bevelled at a suitable angle to the axis of the inlet port, as desired, on the side of the cylinder head adjacent to cylinder block 10. Induction passage 18, as is well known, is curved in its longitudinal direction at least closely adjacent to the inlet port thereof to change the direction of induction fluid flow therethrough so that fluid flow is directed downward toward the combustion chamber. As shown, the induction passage 18 is thus provided with an outside bend 18a and an inside bend 18b.  
  In the embodiment disclosed, the inlet port 20 adjacent to the valve seat 22 is formed by a stepped bore inclined at an angle to the axis of the valve seat 22 portion of the inlet port, to be, in effect, a continuation of induction passage 18. This stepped bore provides an annular groove 24 in the cylinder head, for a purpose to be described, at the junction of the induction passage 18 with inlet port 20.  
  Flow through the inlet port 20 into the combustion chamber is regulated by an articulated, springcontrolled intake poppet valve, generally designated 30, having a valve head 32 in the form of a disc formed as a body of revolution about an axis 34 with a valve face 36 on one side thereof, which in the embodiment illustrated is flat, and a valve back 38 on its other side.  
 The valve head is provided on its valve back 38 side with a ball receiving socket portion 40, for a purpose to be described. The outer peripheral rim of the valve head 32 is provided with an annular bevelled seating portion 42 adapted to seat against the valve seat 22 in the cylinder head 16, the axis of the valve head 32 when seated. as seen in FIG. 2, being coaxial with the axis of the valve seat 22 portion of the inlet port 20.  
  The valve head 32 is normally biased to its seated position with respect to the valve seat 22, the position shown in FIG. 2, by a coiled tension spring 50, positioned in the intake port and suitably fixed at one end, as by weld 52, to the valve back 38 of the valve head and having its other end suitably fixed at its other end to the cylinder head. In the embodiment shown, this is accomplished by providing the spring 50 with an enlarged spring coil 50a, encircling the main body portion of the spring which is engaged in the annular groove 24 provided for this purpose in the cylinder head. It is to be realized, however, that other suitable means may be used to retain the opposite end of the valve spring 50 from valve head 32 in the intake port in the cylinder head l6.  
  The poppet valve 30 also includes a suitable actuator for the valve head 32 which, in the embodiment illustrated, is a valve stem 60 formed as a separate element from the valve head 32 but pivotally interconnected therewith in a manner to be described. As shown, the stem 60, of cylindrical rod configuration, is provided at one end, its bottom end as seen in the drawing, with suitable means for pivotal interconnection or abutment with the valve head 32, this means for pivotal interconnection with the valve head 32, in the embodiment shown, being in the form of a ball shaped tip 62 formed complementary to the ball receiving socket 40 of the valve head so as to be socketably mated therewith. The cylindrical rod portion of the stem 60 is reciprocally journalled in a suitable stem guide, such as bore 64 in the cylinder head 16, with the opposite end of the stem extending outward from the cylinder head for actuation in one direction axially, by means of, for example, a suitable rocker arm or cam, not shown, engaging the free end of this stem. Axial movement of the stem 60 in the opposite direction is effected in a normal manner by a return spring, not shown, which would conventionally abut at one end against the top of the cylinder head 16 and at its other end against a valve spring retainer cap, not shown, fixed to the valve stem in a conventional manner. A collar 66, which may be formed integral with the stem 60 or as a separate element suitably fixed thereto intermediate the ends thereof, is provided on the valve stem 60 to abut against a shoulder 68 of the cylinder block provided in the induction passage 18 adjacent to and at right angle to the bore 64 to act as a stop for the valve stem 60 to limit its axial movement in one direction, upward as seen in the figures, as moved by the return spring, not shown. Also, as shown, the lower end of the valve stem is loosely encircled by the coiled spring 50.  
  In operation, the valve head 32 is held closed, in the position shown in FIG. 2, by the coiled spring 50 which has one end attached to the valve head 32 and its other end attached to the cylinder head within the intake port 20, the conventional return spring, not shown, merely moving the valve stem to the position shown in FIG. 2, to permit the spring 50 to close the valve head.  
  When the valve stem isactuated, that is, moved axially to the position shown in FIG. 1, engagement of the ball 62 in the socket 40 of the valve head will move the valve head downward against the biasing action of the spring 50 to effect unseating of this valve head relative to the valve seat 22 of the inlet port, the valve head moving to the position shown in FIG. 1. Because of the tension force of spring 50, the valve head, fixed to one end of this spring, will move downward relative to the valve seat and will pivot relative to the ball 62 of the valve stem in a counterclockwise direction, with reference to the figures, to the position shown in FIG. 1, so that when the head 32 is in its open position relative to the valve seat of the inlet port 20, an increased sized flow area will be provided on one side of the valve-port, on the left-hand side as seen in FIG. 1, while a reduced flow area will be provided on the opposite side of the valve-port, the right-hand side as seen in this figure.  
  The valve spring 50, during opening movement of the valve head 32, functions to maintain contact between the valve head 32 and the stem and, depending on the characteristics of the spring used, helps to determine the valve head trajectory during stem movement in a valve opening direction. It is to be realized that in addition to the spring design characteristics, the valve stem angle, the location of the pivotal contact area between the valve head 32 relative to the axis of the valve head and the stem 60 and the shape of the pivotal connection between valve head and valve stem will also effect the valve head trajectory in an opening direction. Thus, by appropriate selection of the location of opening force application relative to spring retaining force application, it is possible to magnify the motion of the valve head to provide an increased flow area for a prescribed valve stem lift.  
  With the valve head 32 opened to the position shown in FIG. 1, to provide more flow area on one side of the valve head relative to the inlet port than on the other side, substantially more induction fluid will flow through the larger flow area, with its relatively low flow coefficient, than through the reduced flow area into the combustion chamber. These unbalanced flow paths on opposite sides of the valve head will cause the induction fluid entering the combustion chamber through these flow areas to mix together within the combustion chamber to effect whirling flow of induction fluid throughout the combustion chamber.  
  It is apparent from the above description of the subject articulated, spring-controlled intake poppet valve that when this valve is used in the intake port of a reciprocating internal combustion engine, it will permit the generation of strong combustion chamber swirling motion of induction fluid, it will reduce extraneous and undesired superimposed fluid motion in the combustion chamber, it will provide an improved intake valveport flow coefficient and, it will provide for increased valve motion without increasing valve-train loading.  
  Although the subject valve structure has been illustrated and described as an intake valve, it is to be realized that this valve structure could be used, if desired, as a discharge valve.  
 What is claimed is:  
  1. A valve controlled induction system for an internal combustion engine including a cylinder head having an induction passage therein terminating at an annular bevelled valve seat defining an inlet port to a combustion chamber on the combustion side of the cylinder head, a through stem guide bore in said cylinder head said induction passage, a valve stem reciprocally ;ournalled in said stem guide bore with one end of said valve stem extending from said cylinder head and its other end positioned, when said valve stem is in its fully :xtended position, closely adjacent to said valve seat, an induction valve head pivotally abutting said other end of said valve stem. a coiled tension spring encircling said valve stem with one end of said coiled spring secured to said cylinder head within said inlet port and its opposite end secured to said valve head. said valve spring normally biasing said valve head into seating engagement with said valve seat and functioning to maintain contact between the valve head and said valve stem.  
  2. A valve controlled induction system for an internal combustion engine according to claim I wherein said valve head is in the form of a body of revolution about an axis with a valve face on one side and a valve back on the opposite side, said valve back including a ball receiving socket portion, the outer periphery of said valve head being provided with a bevelled seating portion complementary to said valve seat and, wherein said valve stem includes at said other end thereof a ballshaped portion socketably received in said ball receiving socket.  
  3. A valve controlled induction system for an internal combustion engine according to claim 2 wherein said valve stem further includes a collar intermediate the ends thereof adapted to abut against said cylinder head to limit axial movement of said valve stem in one direction.  
  4. An articulated, spring-controlled poppet valve for use in the intake port in the cylinder head of an engine, said poppet valve including a valve head and a separate valve stem adapted to pivotably abut one side of said valve head, and a coiled spring secured at one end to said one side of said valve head and adapted to be positioned in the intake port encircling said valve stem and to have its other end fixed to the cylinder head within the intake port.  
  5. an articulated, spring-controlled poppet valve according to claim 4 wherein said valve head is in the form of a body of revolution about an axis to provide an outer peripheral surface with a bevelled seating portion thereon and having a valve face on one side and a valve back on the opposite side, said valve back including a ball receiving socket portion and, wherein said valve stem includes at one end thereof a ball-shaped portion socketably receivable in said ball receiving socket portion.  
  6. An articulated, spring-controlled poppet valve according to claim 5, wherein said valve stem further includes a fixed annular collar extending radially outward from the main body portion of said valve stem interme diate the ends thereof.