Patent ID: 7334501
Filing Date: 2008-02-26
Classification: B63H,F16H,Y10T

Abstract:
1. A gear case assembly with a pressure-compensating function for use as a lower part of a marine propulsion machine, said gear case assembly comprising: a gear case provided with a substantially vertical drive shaft receiving bore formed therein to receive a drive shaft, said gear case also having a gear chamber formed therein which is connected to the lower end of the drive shaft receiving bore, the drive shaft being rotatably supported in said drive shaft receiving bore, a bevel gear mechanism for transmitting power from the drive shaft to a propeller shaft, and a forward/backward selector clutch mechanism disposed in said gear chamber, said gear case further having a shift rod receiving bore formed therein which is substantially parallel to the drive shaft receiving bore, a shift rod supported in said shift rod receiving bore for operating the forward/backward selector clutch mechanism, said shift rod receiving bore having an upper end opening in an upper surface of the gear case, and said gear case having a connecting hole formed therein connecting an upper part of the drive shaft receiving bore and an upper part of the shift rod receiving bore; and a covering member attached to the upper surface of the gear case so as to cover the upper end of the shift rod receiving bore, said covering member being provided with an opening through which the shift rod is passed into the shift rod receiving bore, and said covering member also having a body part, and a pressure-compensating wall bulging upward from the body part, wherein said gear case and said covering member cooperate to define a pressure-compensating chamber.