Abstract: A change-speed gearing assembly including upper and lower bearings carried on a partition wall of a casing for the assembly respectively for supporting thereon input and counter shafts, and a bearing retainer secured in a fluid-tight manner to the outside face of the partition wall to retain both the bearings in place. The input shaft extends outwardly through an annular seal member carried on the upper portion of the bearing retainer coaxially with the upper bearing. The bearing retainer is formed with upper and lower cavities and is formed at one side thereof with a vertical groove which opens at its upper end into a side portion of the upper cavity located above the lower edge of the seal member and at its lower end into the upper portion of the lower cavity to maintain the level of lubricating oil in the upper cavity above the lower edge of the seal member.

Abstract: A gear transmission including a casing containing lubrication oil therein, an input gear rotatably mounted in the casing, an output power shaft being supported at one end thereof in the input gear through an output pilot bearing and being rotatable with respect to the input gear, and a gear piece rigidly secured to and arranged concentrically with the input gear. A bearing lubrication mechanism consisting of a cavity formed in the gear piece and an oil aperture formed in the input gear.

Abstract: A gear transmission including a casing containing lubrication oil therein, a counter shaft rotatably mounted in the casing and constantly transmitting rotational movement from a power input shaft by gear trains, a counter shift gear rotatably mounted on the counter shaft through a bearing, a shift gear rigidly mounted on a power output shaft and being in constant meshing engagement with the counter shift gear, and a clutch for interrupting the relative rotational movement between the counter shaft and the counter shift gear. The counter shaft is provided therein with an oil port, one end of which is opened at one edge surface of the counter shaft and the other end of which is opened at the abutting surface between the counter shaft and the bearings. Lubrication oil is supplied to the bearings through the oil port.