Patent ID: 12188354

DETAILED DESCRIPTION OF THE INVENTION

The intended purpose of the following detailed description of the invention and the phraseology and terminology employed therein is to describe what is shown in the drawings, which include the depiction of and/or relate to one or more nonlimiting embodiments of the invention, and to describe certain but not all aspects of what is depicted in the drawings, including the embodiment(s) depicted in the drawings. The following detailed description also describes certain investigations relating to the embodiment(s) depicted in the drawings, and identifies certain but not all alternatives of the embodiment(s) depicted in the drawings. As nonlimiting examples, the invention encompasses additional or alternative embodiments in which one or more features or aspects shown and/or described as part of a particular embodiment could be eliminated. Therefore, the appended claims, and not the detailed description, are intended to particularly point out subject matter regarded to be aspects of the invention, including certain but not necessarily all of the aspects and alternatives described in the detailed description.

FIG.1schematically represents a reciprocating assembly10adapted for use in a reciprocating engine, such as but not limited to a steam engine or an internal combustion engine, andFIGS.2through4Dschematically represent one or more reciprocating assemblies10ofFIG.1disposed within an engine mainframe50of a reciprocating engine140. To facilitate the description provided below of the reciprocating assembly10and reciprocating engine140represented in the drawings, relative terms, including but not limited to, “proximal,” “distal,” “vertical,” “horizontal,” “lateral,” “front,” “rear,” “side,” “forward,” “rearward,” “top,” “bottom,” “upper,” “lower,” “above,” “below,” “right,” “left,” etc., may be used in reference to the orientation of the reciprocating assembly10and reciprocating engine140as represented inFIGS.1and2. All such relative terms are intended to indicate the construction and relative orientations of components and features of the reciprocating assembly10and reciprocating engine140, and therefore are relative terms that are useful to describe the illustrated embodiments but should not be otherwise interpreted as limiting the scope of the invention.

The reciprocating assembly10is represented inFIG.1as comprising a pinion gear70, a timing arm74, a timing plate112that defines a timing slot114, and a dual gear rack90in which first and second gear racks104and108are defined. However, as shown inFIG.3, a single reciprocating assembly10may comprise a single pinion gear70and single dual gear rack90that are associated with two timing arms74and two timing plates112each having a timing slot114. InFIG.2, a single reciprocating assembly10ofFIG.1is shown associated with a single bank of cylinders146A-146D and pistons150A-150D within the mainframe50of the engine140, and inFIG.3a pair of reciprocating assemblies10is shown associated with two banks of cylinders within the mainframe50of the engine140. (Due to the orientation of the section shown inFIG.3, only two pistons150A and150B of each bank are depicted and the cylinders are unnumbered.) It should be understood fromFIG.3that the engine140may comprise any number of reciprocating assemblies10associated with any number of banks of cylinders146A-146D and pistons150A-150D.

FIG.2depicts the engine mainframe50as having an upper wall52, a lower wall54, and two sidewalls56and58.FIG.3further depicts the engine mainframe50as having oppositely-disposed first and second endwalls60and62, which in combination with the upper wall52, lower wall54, and sidewalls56and58define and enclose an interior chamber64of the mainframe50. The engine mainframe50serves as an enclosure for internal components of the reciprocating engine140, including the pinion gear70, timing arm(s)74, timing plate(s)112, and dual gear rack90of at least one reciprocating assembly10as described in detail below, as well as a suitable lubricant. Within the interior chamber64of the engine mainframe50, the sidewalls56and58of the mainframe50define a parallel pair of slide racks66for the single reciprocating assembly10visible inFIG.2. Each slide rack66slidably receives one of two oppositely-disposed edges of the dual gear rack90of the reciprocating assembly10. The slide racks66serve as guides for the dual gear rack90, limiting the dual gear rack90to a reciprocating motion within a single plane. An output shaft68partially resides within the interior chamber64of the engine mainframe50, with opposite ends of the output shaft68protruding from the first and second endwalls60and62of the mainframe50(FIG.3). The engine mainframe50and the reciprocating assembly10may be constructed from various materials of types known or otherwise capable of use in reciprocating engines, as nonlimiting examples, iron alloys (including steel alloys), aluminum alloys, etc.

The pinion gear70of the reciprocating assembly10is rigidly attached to the output shaft68through any suitable type of connection, such as splines (as shown), a key and keyway, etc. The pinion gear70is generally configured to have a circular or disk shape having an outer circumference and pinion teeth72disposed along less than half of the outer circumference. A timing arm74is also rigidly attached to the output shaft68through any suitable type of connection, such as a splines (as shown), a key and keyway, etc., and/or may optionally be coupled to the pinion gear70. Both the pinion gear70and timing arm74rotate with the output shaft68. The timing arm74radially extends from the output shaft68and terminates at a distal end76that is offset from the output shaft68. A timing pin78is disposed at the distal end76of the timing arm74and extends from the timing arm74in a direction approximately parallel to the axis of the output shaft68. The timing pin78resides within the timing slot114(whose outer perimeter is shown with broken lines inFIGS.1,2, and4A-4B) and cams against an outer perimeter112A of the timing plate112, which is rigidly secured to the dual gear rack90so as to reciprocate therewith. The outer perimeter112A of the timing plate112and the timing slot114defined thereby are elliptical in shape. Due to its elliptical shape, the timing slot114has oppositely-disposed upper and lower vertices116and118and two oppositely-disposed co-vertices120and122(FIG.1). Whereas the timing slot114is physically defined at its interior by the outer perimeter112A of the timing plate112, the outer perimeter of the slot114is physically limited only at its upper and lower vertices116and118by camming surfaces100defined by two ends92and94of the dual gear rack90. (The ends92and94will hereinafter be referred to as end plates92and94, though without the intent or effect of limiting the ends92and94of the dual gear rack90to plates or any other particular structure, other than that the end plates92and94structural elements that may be coupled to or otherwise form parts of the dual gear rack90.) As such, the timing slot114is configured to retain the timing pin78of the timing arm74as the output shaft68rotates, and assists in controlling the rotation of the pinion gear70as more fully described below. The end plates92and94of the dual gear rack90include, respectively, first and second pairs of connecting arm attachments124and126that are adapted to couple the rack90to two or more pistons, such as the pistons150A-D represented inFIGS.2,3, and4A-D. In the arrangement shown inFIG.2, with the pistons150A-150D coupled in pairs to the connecting arm attachments124and126, the pistons150A and150B are parallel and move (reciprocate) in parallel unison within their cylinders146A and146B, and the pistons150C and150D are parallel and move (reciprocate) in parallel unison within their cylinders146C and146D.

In addition to the end plates92and94, the dual gear rack90includes oppositely-disposed first and second side plates96and98. The dual gear rack90and its end plates92and94and first and second side plates96and98define a cavity101in which the pinion gear70and a portion of the output shaft68are disposed. The first gear rack104resides at the first side plate96of the dual gear rack90and the second gear rack108resides at the second side plate98of the dual gear rack90, and both gear racks104and108extend in parallel between the first and second end plates92and94of the dual gear rack90. Each of the first and second gear racks104and108have gear rack teeth106and110, respectively, that span at least a portion of the length of its respective gear rack104and108. The gear rack teeth106and110are configured to engage and mesh with the teeth72of the pinion gear70, though not simultaneously but in alternating sequence, e.g., first the gear rack teeth106, then the gear rack teeth110, then the gear rack teeth106, etc. For this reason, there are no teeth72on the pinion70that are diametrically opposite each other.

As noted above, a reciprocating engine (such as140) may utilize any number of the reciprocating assembly10ofFIG.1. InFIGS.2and4A-4D, the engine140is schematically represented as using a single reciprocating assembly10connected to four pistons150A-150D arranged for reciprocating within four cylinders146A-146D, respectively, of the reciprocating engine140, andFIG.3schematically represents the engine140as using a pair of the reciprocating assembly10each connected to four pistons (of which only two,150A and150B, are visible) arranged for reciprocating within four cylinders (unnumbered). As will become apparent from the following discussion, the pistons150A-150D are interconnected through the pinion gear70and dual gear rack90of the reciprocating assembly10in a manner capable of improving the power and efficiency of the reciprocating engine140by reducing the loss of torque at the top-dead-center (TDC) position of each piston150A-150D.

The cylinders146A-146D are represented inFIG.2as being disposed between the sidewalls56and58of the engine mainframe50and closed by the upper and lower walls52and54, which as represented may be cylinder heads of the engine140and will be referred to as such in the following discussion. The pistons150A-150D are individually connected with a connecting rod152A-152D to a respective connecting arm attachment124or126of the dual gear rack90. Each cylinder146A-146D has a “top” and “bottom” corresponding to the nearest and farthest travel of the pistons150A-150D relative to the upper or lower cylinder head52or54that closes their respective cylinder146A-146D. For example, the pistons150A and150B are depicted inFIG.2at or near their TDC positions within the respective cylinders146A and146B (which, as designated inFIG.2, corresponds to exhaust and compression cycles if the engine140is a four-stroke engine), and the pistons150C and150D are depicted inFIG.2at or near their BDC positions (corresponding to power and intake cycles of the engine140). While the operation of a four-stroke combustion engine is indicated inFIG.2, it should be appreciated that other engines, including but not limited to two-stroke and six-stroke combustion engines and steam engines are also encompassed by the teachings of this invention. The cylinders146A-146D and pistons150A-150D may be of any suitable construction and utilize or operate in combination with conventional engine components, including camshafts with conventional timing driven by either gears, chains, or belts, whichever would be applicable depending upon the implementation. Direct overhead cams are also contemplated for servicing each piston150A-150D. Further, a conventional ignition system is also contemplated depending upon the application.

For purposes of further discussion,FIG.2will be described as depicting the pistons150A and150B at TDC, i.e., at the top of their respective cylinder146A and146B and their nearest location relative to the cylinder head52, and depicting the pistons150C and150D at BDC, i.e., at the bottom of their respective cylinder146C and146D and their farthest extent from the cylinder head54. In the configuration depicted inFIG.2, the timing pin78of the timing arm74is at the vertex118(FIG.1) of the timing slot114, and the teeth72of the pinion gear70are briefly not engaged with the teeth106and110of either gear rack104or108. As labeled inFIG.2, this orientation is configured for combustion to be initiated in the cylinder146B to cycle the entire reciprocating assembly10and its dual gear rack90toward the opposite end of the mainframe50, i.e., toward the cylinder head54.

As previously noted,FIG.3schematically represents a cross-sectional view of the engine140ofFIG.2as comprising two cylinder banks, labeled as200and202. Each bank200and202comprises a reciprocating assembly10, four pistons150A-D (of which only pistons150A and150B are visible) within four cylinders146A-D (unnumbered), etc., as depicted and described forFIG.2. As was noted previously, each reciprocating assembly10depicted inFIG.3includes a single pinion gear70and single dual gear rack90that are associated with two timing arms74and two timing plates112each having a timing slot114. The pinion gear70and dual gear rack90of each reciprocating assembly10are between the two timing arms70and timing plates112of the reciprocating assembly10to promote dynamic balancing of the engine140, though it is foreseeable that other arrangements and balancing techniques could be used.

The reciprocating engine ofFIG.3depicts the first and second endwalls60and62and the sidewalls56and58of the engine mainframe50. The output shaft68extends through the engine mainframe50and beyond the first and second endwalls60and62. The endwalls60and62each include a seal210and212for retaining a lubricant within the chamber64of the engine mainframe50, and a bearing214and216located adjacent its respective seal210or212. Directly adjacent the bearing214is an oil pump220. A center bearing218is disposed between the first cylinder bank200and the second cylinder bank202.

FIGS.4A through4Dschematically represent different stages of a combustion cycle of the engine140. The cylinders146A-146D are omitted for purposes of simplicity of the illustrations.FIG.4Arepresents the pistons150A and150B at their TDC positions (i.e., at the tops of their respective cylinders146A and146B) such that (as evident fromFIG.2and the location of the mainframe50inFIGS.4A-4D) the dual gear rack90is positioned adjacent the cylinder head52of the engine mainframe50. The pistons150C and150D are located at their BDC positions (i.e., at the bottoms of their respective cylinders146C and146D) such that (as evident fromFIG.2) the dual gear rack90is positioned remote from the cylinder head54of the engine mainframe50. InFIG.4A, the timing pin78is at the vertex118of the timing slot114. Additionally, the teeth72of the pinion gear70are aligned to mesh with the second gear rack teeth110of the second gear rack108. The engagement of the teeth72of the pinion gear70immediately before and after the pistons150A and150B are at TDC and the pistons150C and150D are at BDC reduce the loss of torque typically associated with pistons at TDC positions of conventional reciprocating engines.

As represented inFIG.4B, combustion from within either cylinder146A or146B associated with the piston150A or150B causes the combusted piston150A or150B and corresponding connecting rod152A or152B to act on the dual gear rack90, causing the dual gear rack90to move in a direction away from the cylinder head52toward the lower cylinder head54of the engine140. As the dual gear rack90is moved by the piston150A or150B, the second gear rack teeth110continue to mesh with the teeth72of the pinion gear70and rotate the pinion gear70and the output shaft68. At the same time, the timing pin78of the timing arm74travels within the timing slot114toward the co-vertex120of the timing slot114. InFIG.4B, the dual gear rack90has traveled approximately halfway toward the lower cylinder head54of the engine140at a point where the timing pin78is located at the co-vertex120.

As the combustion cycle continues, the dual gear rack90continues to move toward the lower cylinder head54, causing the pinion gear70to rotate the output shaft68until the dual gear rack90is in proximity of the cylinder head54as depicted inFIG.4C. At this point, the engine140is halfway through a single combustion cycle or revolution of the output shaft68. The pistons150A and150B are located at their BDC positions, and the pistons150C and150D are located at their TDC positions. InFIG.4C, the timing pin78is at the vertex116of the timing slot114. Additionally, the teeth72of the pinion gear70are aligned to mesh with the first gear rack teeth106of the first gear rack104. The engagement of the teeth72of the pinion gear70shortly after the pistons150C and150D are at TDC reduce the loss of torque typically associated with pistons at TDC positions of conventional reciprocating engines.

As represented inFIG.4D, combustion from within either cylinder146C or146D associated with the pistons150C and150D causes the combusted piston150C or150D to act on the dual gear rack90, causing the dual gear rack90to move in a direction away from the lower cylinder head54of the engine140toward the upper cylinder head52. As the dual gear rack90is moved by the piston150C or150D, the first gear rack teeth106continue to mesh with the teeth72of the pinion gear70and rotate the pinion gear70and the output shaft68. At the same time, the timing pin78of the timing arm74travels within a timing slot114toward the co-vertex122of the timing slot114. As depicted inFIG.4D, the dual gear rack90has traveled approximately halfway toward the upper cylinder head52of the engine140at a point where the timing pin78is located at the co-vertex122.

As evident from the above, during a full combustion cycle the reciprocating engine140completes a half-cycle during which the timing pin78travels within the timing slot114from the co-vertex120(FIG.4B) to the co-vertex122(FIG.4D), the timing arm74causes the teeth72of the pinion gear70that are meshed with the gear rack teeth110of the second gear rack108to unmesh, rotate, and mesh with the gear rack teeth106of the first gear rack104. Likewise, as the reciprocating engine140completes a half-cycle during which the timing pin78travels within the timing slot114from the co-vertex122(FIG.4D) to the co-vertex120(FIG.4B), the timing arm74causes the pinion gear teeth72meshed with the teeth106of the second gear rack104to unmesh, rotate, and mesh with the teeth110of the first gear rack108. The described cycle would continue with combustion in the cylinders146A and146B alternating and combustion in the cylinders146C and146D also alternating to create a continually operating reciprocating engine140that continually rotates the output shaft68. The output shaft68may then be connected to power a desired application.

It is contemplated that the order of the cylinder firing of four pistons coupled to the pinion gear70and dual gear rack90of the reciprocating assembly10represented in the drawings may be (1) the cylinder146A, (2) the cylinder146D, (3) the cylinder146B, and then (4) the cylinder146C. This series may be considered a single cycle of the reciprocating engine140. The addition of the second bank202ofFIG.3and associated cylinders would follow the same cycle as described above for the cylinders146A through146D. With the cylinders of the second bank202arranged and designated in the same manner as the first bank200, the firing order may be: (1) the cylinder146B, (2) the cylinder146C, (3) the cylinder146A, and (4) the cylinder146D. In a configuration containing eight cylinders, the simultaneous firing of the first bank200and the second bank202may be: (1) cylinder146A of the first bank200and cylinder146B of the second bank202, (2) cylinder146D of the first bank200and cylinder146C of the second bank202, (3) cylinder146B of the first bank200and cylinder146A of the second bank202, and (4) cylinder146C of the first bank200and cylinder146D of the second bank202.

As previously noted above, though the foregoing detailed description describes certain aspects of one or more particular embodiments of the invention, alternatives could be adopted by one skilled in the art. For example, the reciprocating engine and its components could differ in appearance and construction from the embodiments described herein and shown in the drawings, functions of certain components of the reciprocating engine could be performed by components of different construction but capable of a similar (though not necessarily equivalent) function, and various materials could be used in the fabrication of the reciprocating engine and/or its components. Furthermore, it should be appreciated that certain characteristics of an engine incorporating the reciprocating assembly10can be adjusted and tailored by modifying the radii of curvature at the vertices116and118and co-vertices12and122of the timing slot114, for example, by modifying the radii of curvature at the vertices116and118to modify the acceleration and deceleration characteristics of the pistons150A-D as they approach and depart from their TDC positions. As such, and again as was previously noted, it should be understood that the invention is not necessarily limited to any particular embodiment described herein or illustrated in the drawings.