Single-cylinder internal combustion engine

Claim 2

A single-cylinder internal combustion engine comprising a crankcase with a bearing bore extending through opposite frontwalls of the crankcase, tapered-roller bearings, each of them located in the bearing bore of one of the two crankcase front walls, a crankshaft supported by said tapered-roller bearings and having a crankpin, a connecting rod carried on said crankpin by means of an antifriction bearings, a lubricating system for the lubrication of said antifriction bearing of the connecting rod, comprising a vane-type oil pump driven by means of said crankshaft and consisting of a pump shaft, a ring entrained by the pump shaft, an abutment for said ring, rigidly mounted on the said crankcase, spring means provided on said pump shaft and engaging with said ring for the purpose of pressing same against said abutment, an annular groove on the side of said ring facing the abutment, said annular groove extending in concentric relation to the axis of said pump shaft, the depth of the annular groove decreasing from a point of maximum depth to a point diametrically opposite where the depth of the annular groove is substantially zero, a receiving bore in said abutment which is open in the direction of said annular groove, a pin slidably guided in said receiving bore and engaging with said annular groove, a compression spring provided in said receiving bore for the purpose of pressing said pin against the annular groove, said pin dividing the annular groove in a circumferential direction into a suction chamber and a delivery chamber of the pump, a suction bore impinged upon by the lubricating oil and arranged in said abutment beside the receiving bore including said pin and terminating in said suction chamber of the pump, an oil discharge bore provided in said abutment beside said receiving bore on the side opposite the suction bore, and terminating in said delivery chamber of the pump, said oil discharge bore communicating with a transverse bore of said crankpin terminating in said antifriction bearing of the connecting rod.

Claim 3

A single-cylinder internal combustion engine comprising a crankcase with a bearing bore extending through opposite front-walls of the crankcase, tapered-roller bearings, each of them located in the bearing bore of one of the two crankcase front walls, a crankshaft supported by said tapered-roller bearings and having a crankpin, a connecting rod carried on said crankpin by means of an antifriction bearings, a lubricating system for the lubrication of said antifriction bearing of the connecting rod, comprising a vane-type oil pump driven by means of said crankshaft and consisting of a pump shaft, a ring entrained by the pump shaft, an abutment for said ring, rigidly mounted on the said crankcase, spring means provided on said pump shaft and engaging with said ring for the purpose of pressing same against said abutment, an annular groove on the side of said ring facing the abutment, said annular groove extending in concentric relation to the axis of said pump shaft, the depth of the annular groove decreasing from a point of maximum depth to a point diametrically opposite where the depth of the annular groove is substantially zero, a receiving bore in said abutment which is open in the direction of said annular groove, a pin slidably guided in said receiving bore and engaging with said annular groove, a compression spring provided in said receiving bore for the purpose of pressing said pin against the annular groove, said pin dividing the annular groove in a circumferential direction into a suction chamber and a delivery chamber of the pump, a suction bore impinged upon by the lubricating oil and arranged in said abutment beside the receiving bore including said pin and terminating in said suction chamber of the pump, an oil discharge bore provided in said abutment beside said receiving bore on the side opposite the suction bore, and terminating in said delivery chamber of the pump, said oil discharge bore communicating with a transverse bore of said crankpin terminating in said antifriction bearing of the connecting rod.

Claim 4

A single-cylinder internal combustion engine comprising a crankcase with a bearing bore extending through opposite front-walls of the crankcase, tapered-roller bearings, each of them located in the bearing bore of one of the two crankcase front walls, a crankshaft supported by said tapered-roller bearings and having a crankpin, a connecting rod carried on said crankpin by means of an antifriction bearings, a lubricating system for the lubrication of said antifriction bearing of the connecting rod, comprising a vane-type oil pump driven by means of said crankshaft and consisting of a pump shaft, a ring entrained by the pump shaft, an abutment for said ring, rigidly mounted on the said crankcase, spring means provided on said pump shaft and engaging with said ring for the purpose of pressing same against said abutment, an annular groove on the side of said ring facing the abutment, said annular groove extending in concentric relation to the axis of said pump shaft, the depth of the annular groove decreasing from a point of maximum depth to a point diametrically opposite where the depth of the annular groove is substantially zero, a receiving bore in said abutment which is open in the direction of said annular groove, a pin slidably guided in said receiving bore and engaging with said annular groove, a compression spring provided in said receiving bore for the purpose of pressing said pin against the annular groove, said pin dividing the annular groove in a circumferential direction into a suction chamber and a delivery chamber of the pump, a suction bore impinged upon by the lubricating oil and arranged in said abutment beside the receiving bore including said pin and terminating in said suction chamber of the pump, an oil discharge bore provided in said abutment beside said receiving bore on the side opposite the suction bore, and terminating in said delivery chamber of the pump, said oil discharge bore communicating with a transverse bore of said crankpin terminating in said antifriction bearing of the connecting rod.

Claim 5

A single-cylinder internal combustion engine according to claim 1, comprising an oil cage mounted on a crank web of said crankshaft facing said vane-type oil pump and having a perforated front end facing the vane-type oil pump, a longitudinal bore in said crankpin of the crankshaft originating at said oil cage and communicating with said transverse bore of the crankpin, an annular collar projecting inwardly from the tapered-roller bearing adjacent to the oil cage and protruding into said perforation of the oil cage, said collar defining in conjunction with the crankshAft and annular chamber communicating with said oil discharge bore of the vane-type oil pump.

Claim 6

A single-cylinder internal combustion engine according to claim 2, wherein said oil cage is arranged in eccentric relation to the axis of said crankshaft, said longitudinal bore of the crankpin being located at the point of said oil cage closest to said crankshaft axis.

Claim 7

A single-cylinder internal combustion engine according to claim 1, wherein said ring of the vane-type oil pump has a number of recesses on its circumference, said spring means of the pump consisting of an entrainer disk non-rotatably mounted on said pump shaft and elastically adjoining the inner surface of said ring, said entrainer disk comprising a number of arms engaging with said recesses of said ring.

Claim 8

A single-cylinder internal combustion engine according to claim 1, comprising a cover shutting said bearing bore of the front-end wall of the crankcase off against the outside and defining said abutment of the pump, said suction bore and said discharge bore being provided in said cover, said ring being mounted on the crankshaft between said cover and the adjacent tapered-roller bearing of the crankshaft.