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US 9,032,840 B2Granted
Evacuated transmission case
AssigneeGM Global Technology Operations LLC
InventorGregory P. Prior
Life of this patent
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AssigneeGM Global Technology Operations LLC
InventorGregory P. Prior
Estimating the term…
A vehicle transmission includes at least one rotatable component and is disposed in an environment at a first pressure. A transmission housing includes a sump portion disposed near a bottom portion of the transmission housing, where the transmission housing substantially encloses the at least one rotatable component. A hydraulic fluid is disposed at least partially in the sump portion of the transmission housing and a vacuum source is in pneumatic communication with the transmission housing. The vacuum source at least partially evacuates a gas from the transmission housing so that an interior of the transmission housing is at a second pressure. The at least one rotatable component is partially exposed to a gas at the second pressure and partially submerged in the hydraulic fluid when the transmission is under a predetermined dynamic load.
A vehicle transmission including at least one rotatable component and disposed in an environment at a first pressure, the vehicle transmission comprising:
A method of operating a vehicle transmission including a transmission housing that substantially encloses at least one rotatable component, the transmission housing disposed in an environment at a first pressure and including a sump portion disposed near a bottom of the transmission housing and at least partially filled with hydraulic fluid up to a hydraulic fill line, wherein the transmission housing is in pneumatic communication with a vacuum source, the method comprising the steps of:
Dependencies are inferred from the claim text.