DRIVE UNIT, PARTICULARLY FOR BOATS

Abstract

A drive unit comprising a transmission with two coaxial bevel gears (11, 12) fitted opposite one another on the same engine shaft (10), which engage a bevel gear (13) fitted to a shaft (14) perpendicular to the preceding one, means designed to mesh said engine shaft with one or other of said bevel gears, constituted by clutches (20, 21) housed in the body of said bevel gears (12, 11) and controlled by a pressurised fluid, wherein pipes (24, 25), designed to convey said pressurised fluid, are formed in said engine shaft (10), wherein, in order to supply pressurised oil to said pipes (24, 25), an axial inlet pipe (34) is formed in the head of said engine shaft (10), which said axial pipe (34) feeds a distributor (35) constituted by a valve that slides on said engine shaft, which said slide valve (35) can move between two positions in which it places said input pipe (34) in communication with one of said pipes (24, 25).

Description

FIG. 1 schematically illustrates the general structure of a drive unit to which the teachings according to the invention are applied;

FIG. 2 shows a cross-section of a drive unit according to the invention with one clutch engaged;

FIG. 3 shows a cross-section of the same drive unit with the second clutch engaged;

FIG. 4 shows a cross-section of the engine shaft according to planes perpendicular to the axis,

FIGS. 5 and 6 illustrate, again in cross-section, the system of distribution of pressurised oil in the engagement positions of the two clutches.

Claims

1) Drive unit of the type comprising a transmission with two coaxial bevel gears (11, 12) fitted opposite one another on the same engine shaft (10), which engage a bevel gear (13) fitted to a shaft (14) perpendicular to the preceding one, and means designed to mesh said engine shaft with one or other of said bevel gears, constituted by clutches (20, 21) housed in the body of said bevel gears (12, 11) and controlled by a pressurised fluid, wherein pipes (24, 25), designed to convey said pressurised fluid, are formed in said engine shaft (10), wherein, in order to supply pressurised oil to said pipes (24, 25), an axial inlet pipe (34) is formed in the head of said engine shaft (10), which said axial pipe (34) feeds a distributor (35) constituted by a valve that slides on said engine shaft, which said slide valve (35) can move between two positions in which it places said input pipe (34) in communication with one of said pipes (24, 25).

2) Drive unit as claimed in claim 1, wherein said distributor (35) is mounted via bearings (32) inside a piston (37) which slides in the axial direction of said engine shaft.

3) Drive unit as claimed in claim 2, wherein said clutches (21, 22) are multi-disc clutches.

4) Drive unit as claimed in claim 3, wherein said clutches (21, 22) are the oil-bath type, with forced lubrication.

5) Drive unit as claimed in claim 2, further including a pipe formed inside said engine shaft (10), fed via a radial connector (33), for the lubrication of said clutches (21, 22).