Engine crankshaft torque sensor cartridge

An internal combustion engine comprising:

• an engine block;
• a plurality of pistons reciprocally located within the engine block;
• and
• a crankshaft operably coupled to the plurality of pistons, the crankshaft comprising:
• an output end comprising a rear bearing journal, wherein the rear bearing journal defines a substantially cylindrical cavity having a specific depth within the crankshaft extending from the output end into the rear bearing journal, wherein the cavity defines an inner diameter surface, and wherein the specific depth of the cylindrical cavity is selected to prevent weakening the rear bearing journal in the plane of a bending load;
• at least one torque sensor operatively coupled to the inner diameter surface of the cavity defined by the rear bearing journal of the crankshaft, wherein the at least one torque sensor is configured to generate a torque signal corresponding to a torque exerted on the cylindrical cavity within the rear bearing journal, and wherein the torque exerted on the cylindrical cavity is indicative of a torque output of an engine;
• and
• a sensor capsule having a cylindrical body comprising an outer surface and disposed within the substantially cylindrical cavity, wherein the sensor capsule comprises:
• a flange mechanically coupled to the cylindrical body, wherein the flange is further mechanically coupled to the output end;
• and
• a cylindrical body o-ring disposed between the outer surface of the cylindrical body and configured to contact the inner diameter surface of the substantially cylindrical cavity,
• wherein cylindrical body has an outer diameter less than an inner diameter of the substantially cylindrical cavity;
• and
• wherein the at least one torque sensor is covered by a sensor seal that is impermeable to an engine oil.

A method for measuring torque output of an engine, the method comprising:

• installing a torque sensing crankshaft into the engine, wherein the torque sensing crankshaft comprises:
• an output end comprising a rear bearing journal, wherein the rear bearing journal defines a substantially cylindrical cavity having a specific depth within the crankshaft extending from the output end into the rear bearing journal, wherein the cavity defines an inner diameter surface, and wherein the specific depth of the cylindrical cavity is selected to prevent weakening the rear bearing journal in the plane of a bending load;
• at least one torque sensor operatively coupled to the inner diameter surface of the cavity defined by the rear bearing journal of the crankshaft, wherein the at least one torque sensor is configured to generate a torque signal corresponding to a torque exerted on the cylindrical cavity within the rear bearing journal, and wherein the torque exerted on the cylindrical cavity is indicative of a torque output of an engine;
• and
• a sensor capsule having a cylindrical body comprising an outer surface and disposed within the substantially cylindrical cavity, wherein the sensor capsule comprises:
• a flange mechanically coupled to the cylindrical body, wherein the flange is further mechanically coupled to the output end;
• and
• a cylindrical body o-ring disposed between the outer surface of the cylindrical body and configured to contact the inner diameter surface of the substantially cylindrical cavity,
• wherein cylindrical body has an outer diameter less than an inner diameter of the substantially cylindrical cavity;
• and
• wherein the at least one torque sensor is covered by a sensor seal that is impermeable to an engine oil;
• operating the engine to generate torque on the torque sensing crankshaft;
• and
• obtaining the torque signal from the torque sensor.