GB2128276A - An internal combustion engine differential and expanding-pulley gear combination - Google Patents

Abstract

An engine transmission/differential unit has its differential 16 housed in a case 13 fixed to the engine crankcase 11 to form an extension of one of its lubricated conduits. The differential is driven from the propeller shaft via a belt 18 of an expanding- pulley gear arrangement, a primary shaft 22, and a countershaft 33. Shafts 22 and 33 and their associated gearing constitute a drive reversing unit. <IMAGE>

Description

SPECIFICATION An internal combustion engine conjoined with a differential with transmission external to the two assemblies housed in a single casing The present invention relates to an internal combustion power pack combined with a differential, with an external transmission connecting the two assemblies with which it is conjoined.

The object of the present invention is to embody an engine transmission/differential unit that is highly compact, has the transmission in line with the engine and which, though of only moderate weight, also possesses adequate rigidity.

Further objects of the invention are the reduction of the production and maintenance costs of the assembled unit.

To attain said purposes the present invention embodies an engine transmission/differential unit characterized by the fact that the differential is housed in a case flanged to the crankcase of the engine to form an extension of one of its lubricated conduits and the differential crownwheel has drive imparted to it by a primary shaft disposed parallel to the propeller shaft and connected to it by a transmission featuring flexible belt and variable diameter cone pulleys disposed adjacent to and outside the said crankcase and differential case.

The structural and functional characteristics of the present invention will be more clearly comprehended from the following description of an example of embodiment referred to the attached schematic drawings, in which: Figure 1 is a view in elevation of an engine transmission/differential unit according to the invention Figure 2 is a cross-sectional view of the engine transmission/differential unit taken through line Il-Il of Figure 3, and Figure 3 is a lateral view of the unit with schematic illustration of the essential transmission gearings.

With reference to the drawings, an internal combustion engine 10, to the crankcase 11 of which there is directly connected by flanging 12 a case 1 3 housing a final drive 14 consisting essentially of a drive-reverser 1 5 and a differential 16, is illustrated. A flexible belt and cone pulley system connects said engine 10 to the final drive 14.

The flexible belt and cone pulley system 17, perse known, consists of a drive pulley 19 connected to the flywheel 20 of the engine 10 and a driven pulley 21 solid with the primary shaft 22 of the drive-reverser 15.

The pulleys 19 and 21 are variable-diameter split pulleys which at their widest spacing present the smallest effective diameter to the belt, and vice-versa.

Control means not shown in the drawings vary the diameter of the pulley 19, while the diameter of the pulley 21 is self-adjusted by the pressure of a spring 23 positioned on the shaft 22 and reacting between a disc 24 of said pulley 21 and a raised portion 25, so as to maintain the belt 18 at a pre-set tension.

The shaft 22 within the case 13, in which it is suitably supported by bearings 26, has a grooved profile 27 on which is slidingly mounted a bevel gear 29 driven by a lever or fork (not shown in the drawings).

Said bevel gear 29, depending on its position, meshes with a gearwheel 30 solid with a countershaft 31 or, alternatively, with an idler gearwheel 32.

The second-motion shaft 33 also features teeth 34 which simultaneously mesh with the gearwheel 30 and with the crown-wheel 35 of the differential 1 6, per se of conventional type, from which the half-shafts 28 depart.

The simple shaft of the bevel gear 29 on the grooved profile from the position shown by the solid line in Figure 2 to the position shown by the dashed and dotted line, causes reversal of the drive transmitted.

The case 13 flanged at 12 to form a single whole with the crankcase 11 allows lubrication common with that of the power pack, with consequent lube-oil saving and simplification of maintenance.

The said embodiment according to the invention, also makes it possible to eliminate the connection frame between engine and final drive, thus considerably reducing weight and costs.

The engine transmission/differential unit according to the invention is also highly compact, thus affording rigidity to the unit as a whole.

Claims

1. An engine transmission/differential unit characterized by the fact that the differential is housed in a case flanged to the engine crankcase so as to form an extension of one of its lubricated conduits, and the crown-wheel of the differential receives drive from a primary shaft disposed parallel to the propeller shaft and connected to it by a flexible belt and variable diameter split pulley system, disposed adjacent to and outside said crankcase and case.

2. A unit according to Claim 1, characterized by the fact that between said primary shaft and said crown-wheel provision is made for a countershaft having teeth meshing with said crown-wheel and having another gearwheel meshing with an idler gearwheel, a bevel gear mounted slidingly on the primary shaft being capable of being caused to mesh with said gearwheel or, alternatively, with the idler gearwheel.

3. A unit according to Claim 1, characterized by the fact that the variable-diameter drive pulley,

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (4)

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION An internal combustion engine conjoined with a differential with transmission external to the two assemblies housed in a single casing The present invention relates to an internal combustion power pack combined with a differential, with an external transmission connecting the two assemblies with which it is conjoined. The object of the present invention is to embody an engine transmission/differential unit that is highly compact, has the transmission in line with the engine and which, though of only moderate weight, also possesses adequate rigidity. Further objects of the invention are the reduction of the production and maintenance costs of the assembled unit. To attain said purposes the present invention embodies an engine transmission/differential unit characterized by the fact that the differential is housed in a case flanged to the crankcase of the engine to form an extension of one of its lubricated conduits and the differential crownwheel has drive imparted to it by a primary shaft disposed parallel to the propeller shaft and connected to it by a transmission featuring flexible belt and variable diameter cone pulleys disposed adjacent to and outside the said crankcase and differential case. The structural and functional characteristics of the present invention will be more clearly comprehended from the following description of an example of embodiment referred to the attached schematic drawings, in which: Figure 1 is a view in elevation of an engine transmission/differential unit according to the invention Figure 2 is a cross-sectional view of the engine transmission/differential unit taken through line Il-Il of Figure 3, and Figure 3 is a lateral view of the unit with schematic illustration of the essential transmission gearings. With reference to the drawings, an internal combustion engine 10, to the crankcase 11 of which there is directly connected by flanging 12 a case 1 3 housing a final drive 14 consisting essentially of a drive-reverser 1 5 and a differential 16, is illustrated. A flexible belt and cone pulley system connects said engine 10 to the final drive 14. The flexible belt and cone pulley system 17, perse known, consists of a drive pulley 19 connected to the flywheel 20 of the engine 10 and a driven pulley 21 solid with the primary shaft 22 of the drive-reverser 15. The pulleys 19 and 21 are variable-diameter split pulleys which at their widest spacing present the smallest effective diameter to the belt, and vice-versa. Control means not shown in the drawings vary the diameter of the pulley 19, while the diameter of the pulley 21 is self-adjusted by the pressure of a spring 23 positioned on the shaft 22 and reacting between a disc 24 of said pulley 21 and a raised portion 25, so as to maintain the belt 18 at a pre-set tension. The shaft 22 within the case 13, in which it is suitably supported by bearings 26, has a grooved profile 27 on which is slidingly mounted a bevel gear 29 driven by a lever or fork (not shown in the drawings). Said bevel gear 29, depending on its position, meshes with a gearwheel 30 solid with a countershaft 31 or, alternatively, with an idler gearwheel 32. The second-motion shaft 33 also features teeth 34 which simultaneously mesh with the gearwheel 30 and with the crown-wheel 35 of the differential 1 6, per se of conventional type, from which the half-shafts 28 depart. The simple shaft of the bevel gear 29 on the grooved profile from the position shown by the solid line in Figure 2 to the position shown by the dashed and dotted line, causes reversal of the drive transmitted. The case 13 flanged at 12 to form a single whole with the crankcase 11 allows lubrication common with that of the power pack, with consequent lube-oil saving and simplification of maintenance. The said embodiment according to the invention, also makes it possible to eliminate the connection frame between engine and final drive, thus considerably reducing weight and costs. The engine transmission/differential unit according to the invention is also highly compact, thus affording rigidity to the unit as a whole. Claims

1. An engine transmission/differential unit characterized by the fact that the differential is housed in a case flanged to the engine crankcase so as to form an extension of one of its lubricated conduits, and the crown-wheel of the differential receives drive from a primary shaft disposed parallel to the propeller shaft and connected to it by a flexible belt and variable diameter split pulley system, disposed adjacent to and outside said crankcase and case.

2. A unit according to Claim 1, characterized by the fact that between said primary shaft and said crown-wheel provision is made for a countershaft having teeth meshing with said crown-wheel and having another gearwheel meshing with an idler gearwheel, a bevel gear mounted slidingly on the primary shaft being capable of being caused to mesh with said gearwheel or, alternatively, with the idler gearwheel.

3. A unit according to Claim 1, characterized by the fact that the variable-diameter drive pulley, driven by control means, is directly restrained to the flywheel.

4. An engine transmission/differential unit substantially as hereinbefore described with reference to the accompanying drawings.