Mounting and cooling means for a rotary piston internal combustion engine on a motorcycle

Claim 2

A motor cycle having an engine comprising a housing with a two-lobed epitrochoidal cavity therein, a rotor of generally triangular shape movable within said cavity, a mainshaft on which the rotor is mounted for planetary motion about the axis of the mainshaft such that the apices thereof maintain sliding contact with the peripheral wall of the cavity and thereby form three working chambers which vary in volume as the rotor rotates, an inlet port communicating with the cool lobe of the cavity which bounds the cooler phases of the engine cycle, and an exhaust port which communicates with the hot lobe of the cavity which bounds the hot phases of the engine cycle, the engine being mounted with the axis of the mainshaft substantially normal to a vertical plane containing the longitudinal center line of the motor cycle, with the minor axis of the two-lobed epitrochoidal cavity disposed substantially horizontal or inclined downwardly towards the rear wheel of the motor cycle, with the inlet and exhaust ports for each cavity disposed to the rearward side of the major axis of the two-lobed epitrochoidal cavity, and with the lowermost lobe of the cavity being the hot lobe, the engine housing having a multiplicity of axially spaced circumferential cooling fins formed thereon whereby when the motor cycle is in motion the engine is cooled solely by the natural air flow generated by such motion, the total surface area of the cooling fins on the housing bounding the hot lobe being greater than the total surface area of the cooling fins on the housing bounding the cool lobe.

Claim 3

A motor cycle according to claim 1 wherein the fins on the part of the housing bounding the hot lobe are deeper than the fins on the remainder of the housing.

Claim 4

A motor cycle according to claim 1 wherein the housing comprises a central portion having a two-lobed epitrochoidal bore therethrough and two end plates forming axially spaced end walls of the two-lobed epitrochoidal cavity, the central portion having a multiplicity of axially spaced circumferential cooling fins formed thereon and the end plates having a multiplicity of substantially horizontal cooling fins formed thereon.

Claim 5

A motor cycle according to claim 1 wherein the minor axis of the two-lobed epitrochoidal cavity is inclined to the horizontal at an angle of not more than 45*.

Claim 6

A motor cycle according to claim 4 wherein the minor axis of the two-lobed epitrochoidal cavity is inclined to the horizontal at an angle of 15* to 25*.

Claim 7

A motor cycle according to claim 1 wherein a gearbox is secured to a portion of the housing which lies between said inlet and exhaust ports and a pipe leading to the inlet port passes over the gear-box and a pipe leading to the exhaust port passes under the gear-box, the gear-box containing gearing drive coupled to the mainshaft of the engine.

Claim 8

A motor cycle having an engine comprising a housing having a plurality of two-lobed epitrochoidal cavities therein, an intermediate plate disposed between each adjacent pair of said cavities, a rotor of generally triangular shape mounted within each cavity, a mainshaft on which the rotors are mounted for planetary motion about the axis of the mainshaft such that the apices of each rotor maintain sliding contact with the peripheral wall of its associated cavity and thereby form three working chambers which vary in volume as the rotor rotates, an inlet port communicating with the cool lobe of each cavity which bounds the cooler phases of the engine cycle, and an exhaust port communicating with the hot lobe of each cavity which bounds the hotter phases of the engine cycle, the engine being mounted with the axis of the mainshaft substantially normal to a vertical plane conTaining the longitudinal center line of the motor cycle, with the minor axis of the two-lobed epitrochoidal cavities disposed parallel to each other and disposed substantially horizontal or inclined downwardly towards the rear wheel of the motor cycle, with the inlet and exhaust ports for each cavity disposed to the rearward side of the major axis of the two-lobed epitrochoidal cavity, and with the lowermost lobe of each cavity being the hot lobe, the housing members and the intermediate plates having a multiplicity of axially spaced circumferential cooling fins formed thereon whereby when the motor cycle is in motion the engine is cooled solely by the natural air flow generated by such motion, and the total surface area of the cooling fins formed on the portions of the housing members bounding the hot lobe being greater than the total surface area of the cooling fins formed on the portions of the housing members bounding the cool lobes.

Claim 9

A motor cycle having an engine comprising a housing having a plurality of two-lobed epitrochoidal cavities therein, an intermediate plate disposed between each adjacent pair of said cavities, a rotor of generally triangular shape mounted within each cavity, a mainshaft on which the rotors are mounted for planetary motion about the axis of the mainshaft such that the apices of each rotor maintain sliding contact with the peripheral wall of its associated cavity and thereby form three working chambers which vary in volume as the rotor rotates, an inlet port communicating with the cool lobe of each cavity which bounds the cooler phases of the engine cycle, and an exhaust port communicating with the hot lobe of each cavity which bounds the hotter phases of the engine cycle, the engine being mounted with the axis of the mainshaft substantially normal to a vertical plane conTaining the longitudinal center line of the motor cycle, with the minor axis of the two-lobed epitrochoidal cavities disposed parallel to each other and disposed substantially horizontal or inclined downwardly towards the rear wheel of the motor cycle, with the inlet and exhaust ports for each cavity disposed to the rearward side of the major axis of the two-lobed epitrochoidal cavity, and with the lowermost lobe of each cavity being the hot lobe, the housing members and the intermediate plates having a multiplicity of axially spaced circumferential cooling fins formed thereon whereby when the motor cycle is in motion the engine is cooled solely by the natural air flow generated by such motion, and the total surface area of the cooling fins formed on the portions of the housing members bounding the hot lobe being greater than the total surface area of the cooling fins formed on the portions of the housing members bounding the cool lobes.