US3267917A

US3267917A - Opposed cylinder variable piston stroke internal combustion engine

Info

Publication number: US3267917A
Application number: US383065A
Authority: US
Inventors: Bargero Camillo
Original assignee: Individual
Current assignee: Individual
Priority date: 1964-07-16
Filing date: 1964-07-16
Publication date: 1966-08-23
Anticipated expiration: 1983-08-23

Description

Aug. 23, 1966 c. BARGERO 3,267,917

OPPOSED CYLINDER VARIABLE PISTON STROKE INTERNAL COMBUSTION ENGINE Filed July 16, 1964 2 Sheets-Sheet 1 Aug. 23, 1966 c BARGERO 3,267,917

OPPOSED CYLINDER VA RIABLE PISTON STROKE INTERNAL COMBUSTION ENGINE Filed July 16, 1964 2 Sheets-Sheet 2 Fig.4

United States Patent This invention relates to an opposed cylinder internal combustion engine of the type in which the pistons movable in the opposed cylinders are interconnected by a rack meshing with one toothed wheel at least, from which the rotation of the engine outlet shaft is derived.

Engines of this type are known, in which two oppositely acting one-way clutches are interposed between the outlet shaft and said toothed wheel, a device for reversing rotation being interposed between one of said clutches and the outlet shaft.

With the above described engine arrangement the piston stroke may be made variable. However, this advantage is obtained at the expense of simplicity in construction and useful life of the engine parts, mainly on account of use of the one-way clutches.

This invention provides an opposed cylinder engine of the type specified, wherein the movement of the outlet shaft is derived from the toothed wheel meshing with the rack interconnecting the opposed engine pistons, by the use of a mechanism which is simple in construction and reliable in operation.

To this end the invention provides in an engine of the type specified a second rack meshing with the toothed wheel meshing with the said rack interconnecting the opposed engine pistons at a region which is diametrically opposite said toothed wheel, said second rack being mounted for displacement in the engine crank case and being connected with the pin of a crank carried by the outlet shaft and connected to the latter in a manner allowing some variation of its radius.

Further characteristic features and advantages of this invention will be clearly understood from the appended description referring by way of example to the accompanying drawings which show an embodiment thereof, in which:

FIGURE 1 is a cross sectional view in the longitudinal middle plane of the two opposed cylinders of an engine according to this invention,

FIGURE 2 is a side elevational view on an enlarged scale of certain components of the engine shown in FIG- URE 1,

FIGURE 3 is a sectional view on line IIIIII of FIG- URE 2,

FIGURE 4 is a sectional view on an enlarged scale of a further constructional detail of the engine according to this invention.

The engine as shown on the drawing comprises a pair of opposed cylinders 1, 1' carried by the crank case 2. Pistons 3, 3' are movable within the cylinders 1, 1', respectively, and are interconnected by a rigid rod the middle portion of which is in the form of a double rack. The lower set of teeth 4 in the rack mesh with a toothed wheel 5 fitted on a shaft 6 supported by the engine crank case 2. The toothed wheel 5 meshes in turn with the rack 7 mounted for displacement in supports 8, 9 secured to the crank case.

A connecting rod 10 is articulated to one end of the rack 7 and has its big end fitted on the pin 11 of a crank carried by the outlet shaft 12. The pin 11 extends laterally from a pivot 13 mounted for displacement in a radial guide in the cylindrical bulge 14 at the end of the outlet shaft 12. The top set of teeth 15 in the rack interconnecting the

pistons

2 and 2, meshes with the toothed wheel 16 carried by a shaft 17 extending parallel with the shaft 6 and outlet shaft 12. The toothed wheel 16 meshes with a crank 18 interconnecting two pistons 19, 19' movable in

cylinders

20, 20, respectively, situated above the cylinders 1, 1' of the engine and extending parallel with the latter.

The piston-cylinder unit 19, .1920, 20' acts as a scavenging pump which supplies air, drawn through valves or ports not shown on the drawing, to the cylinders 1, 1 through conduits 21, 21', respectively. The outlet openings of the latter conduits within the cylinders 1, 1 is controlled by

valves

22, 22, respectively, opening to the inside of the cylinders 1, 1' and being normally biased to their closed position by springs 23, 23' the action of

springs

23, 23. A nozzle 24, FIGURE 4, is provided in each valve and connects through a small-diameter axial bore 25 in the valve stem 122 and through a fitting 26 for a small hose 126 with an external fuel supply reservoir (not shown).

The valves 22, 22' together with their stems 122 are each supported by a tubular connecting pipe 121 screwed at its end into an opening in the cylinder top, its other end being screwed to a

conduit

21 or 21. When the valve 22 (or 22') is in its closed position as shown in FIGURE 4, the axial conduit 25 is cut off from the connecting pipe 26 by insertion of the free end of the stem 122 into a blind bore in a tumbler fixed within the connecting pipe 121. Connection is established only after displacement of the valve 22 (or 22') against the action of the spring 23 (or 23) by the air thrust from the cylinder 26 or 20' of the scavenging pump. The valves are moreover each provided in proximity to their respective nozzle 24 with a check valve 124 preventing flow of pressure gases from the cylinder 1 (or 1') into the conduit 25 when the latter is cut off from the connecting pipe 26.

A spark plug 27, 27', respectively, is provided on each cylinder head and is fed with high-voltage electric current from any conventional system.

In operation the engine is started by rotating the outlet shaft or either shaft 6 or 17 when the

toothed wheels

5, 16 are keyed to the latter shafts. Supply of electric current to the spark plug on the cylinder, such as cylinder 1 in which compression of the fuel mixture first takes place effects ignition in the cylinder 1 and the first working stroke of the piston 3. Towards the end of this stroke the piston 3 uncovers the exhaust port 28, thereby starting the exhaust and scavenging stroke on cylinder 1 by means of air flowing from the scavenging pump cylinder 20 above the cylinder 1 in which the expansion stroke has just been performed. Flow of pressure air from the scavenging pump cylinder 20 opens the valve 22 against the spring 23 and simultaneously draws into the cylinder 1 a quantity of liquid fuel through the nozzle 24.

The compression stroke is in the meantime performed in cylinder 1 till spontaneous ignition of the mixture therein, or during a shorter period till a lower compression ratio is reached when ignition is eifected by supplying high-voltage current to the spark plug 27 before compression is driven far enough to effect continuous ignition.

Variation in stroke length of the pistons 3 and '3 of the engine, hence in the stroke of the scavenging pump pistons 19, 19' is made possible by the fact that the spacing of the crank pin 11 from the axis of the outlet shaft 12 is variable Within given limits which are determined dependently upon the maximum admissible stroke of the

pistons

3, 3, which depends upon the spacing of the heads of the two opposed cylinders.

It will be understood that details can be widely varied within the principle of this invention without departing from the scope thereof set forth in the appended claims.

This applies more particularly to the number of cylinders which is an even number and may be larger than two provided further auxiliary components required for transmission of power to a common outlet shaft are associated with every added cylinder pair.

What I claim is:

1. Internal combustion engine of the type having a crank case, at least one pair of opposite coaxial cylinders, one piston slidable in each cylinder, at first rack interconnecting said pistons, an engine outlet shaft and a toothed wheel meshing with said first rack, said engine comprising further a second rack meshing with said toothed wheel at a region thereof which is diametrically opposed to the region at which said toothed wheel meshes with the said first rack, means for supporting said second rack in the engine crank case and means for connecting the said second rack with the engine outlet shaft, the last mentioned means comprising a crank carried by the engine outlet shaft and radially freely displa-ceable with respect to the latter, a pin on said crank parallel to said outlet shaft and a connecting rod interposed between one end of the said second rack and the said pin.

2. Internal combustion engine as set forth in claim 1, comprising further a scavenging pump having a pair of opposed coaxial cylinders each arranged adjacent one of the engine cylinders and being parallel to the latter, and having also a pair of pistons each movable in one of the pump cylinders and a third rack connecting said pistons,

d the said third rack meshing With a toothed Wheel drivingly connected with the said first rack connecting the engine pistons.

3. Internal combustion engine as set forth in claim 2, wherein each cylinder of the scavenging pump is arranged above one engine cylinder and wherein the said third rack meshes with a toothed Wheel meshing simultaneously with the said first rack connecting the said engine pistons.

4. Internal combustion engine as set forth in claim 2 comprising further a pair of conduits each connecting one of the pump cylinders with one of the engine cylinders, and a check valve provided at the inlet of each of said conduits in one engine cylinder and elastic means for each valve urging the latter towards its closed position.

5. Internal combustion engine as set forth in claim 4, having a fuel inflow nozzle incorporated in each valve, the said nozzle being connected with a fuel feeding conduit, a valve being provided between said nozzle and said fuel feeding conduit, the said valve opening on opening of the valve incorporating the said nozzle.

No references cited.

MARK NEWMAN, Primary Examiner.

W. E. BURNS, Assistant Examiner.

Claims

1. INTERNAL COMBUSTION ENGINE OF THE TYPE HAVING A CRANK CASE, AT LEAST ONE PAIR OF OPPOSITE COAXIAL CYLINDERS, ONE PISTON SLIDABLE IN EACH CYLINDER, A FIRST RACK INTERCONNECTING SAID PISTONS, AN ENGINE OUTLET SHAFT AND A TOOTHED WHEEL MESHING WITH SAID FIRST RACK, SAID ENGINE COMPRISING FURTHER A SECOND RACK MESHING WITH SAID TOOTHED WHEEL AT A REGION THEREOF WHICH IS DIAMETRICALLY OPPOSED TO THE REGION AT WHICH SAID TOOTHED WHEEL MESHES WITH THE SAID FIRST RACK, MEANS FOR SUPPORTING SAID SECOND RACK IN THE ENGINE CRANK CASE AND MEANS FOR CONNECTING THE SAID SECOND RACK WITH THE ENGINE OUTLET SHAFT, THE LAST MENTIONED MEANS COMPRISING A CRANK CARRIED BY THE ENGINE OUTLET SHAFT AND RADIALLY FREELY DISPLACEABLE WITH RESPECT TO THE LATTER, A PIN ON SAID CRANK PARALLEL TO SAID OUTLET SHAFT AND A CONNECTING ROD INTERPOSED BETWEEN ONE END OF THE SAID SECOND RACK AND THE SAID PIN.