Oil collector insert for the lubrication of a synchronizer of a gear change of a vehicle

Abstract: An oil collector insert (1) for the lubrication of a synchronizer of a gear change of a vehicle is described, the gear change being of the type in which lubrication oil is housed in a box up to a predetermined level, with a primary shaft disposed above the oil level and a secondary shaft disposed parallel to the primary shaft and below the oil level; the primary shaft bears a synchronization device (2) for at least one gear of the gear change, this device cooperating with a gear engagement fork (11) and in turn comprising at least one engaging sleeve (12) adapted to rotate rigidly with the primary shaft, this sleeve (12) having an outer lateral surface (13) disposed at least partly below the oil level; the oil collector insert (1) is secured detachably to the gear engagement fork (11) and is formed by an oil scraper blade (14) cooperating with the outer lateral surface (13) of the sleeve, the blade being shaped so as to cause the scraped oil to drip towards a respective engagement surface (16) of the synchronization device.

Description: The present invention relates to an oil collector insert for the lubrication of a synchronisation device of a gear change device of a vehicle as specified in the preamble of Claim 1. Such devices are current in the state of the art. The gear change devices currently used in vehicles are normally formed by a box which contains lubricating oil up to a predetermined level; there are also two shafts, one of which, called the primary shaft, is disposed above the oil level and the other, called the secondary shaft, is disposed below this level. Both shafts bear gearing and devices for synchronising the various gears; the gearing borne by the secondary shaft is almost totally immersed in the lubricating oil while the gearing borne by the primary shaft is only partially disposed below the oil level and in some cases are completely above it. During the movement of the vehicle, with the gear change device consequently in rotation, the lubrication of the secondary shaft and the gearing borne thereby follows total immersion in the lubricating oil, while the lubrication of the primary shaft, the gearing borne thereby and in particular the synchronisation device is provided by the oil which, moved by the gearing in rotation keyed rigidly on the secondary shaft, is distributed within the entire gear box and thus also to the assembly of gearing and the synchronisation device mounted on the primary shaft. This technical solution has, however, certain drawbacks, in particular when the vehicle engine is idling, with the gears in neutral during the first few minutes of operation of the engine after cold starting. In these particular conditions, the lubrication of the synchronisation device and the gearing borne by the primary shaft is limited and inadequate, both as a result of the high viscosity of the lubricating fluid in the case of cold starting, and the low speed of rotation of the gearing borne by the secondary shaft and the resultant limited movement of the lubricating oil within the gear box in the case of a vehicle with its engine idling. The inadequate lubrication of the synchronisation device leads to annoying noises in the gear change device when the primary shaft starts to rotate and also to premature wear of the synchronisation device as a result of the friction which is generated when a gear is engaged. The object of the invention is to provide an oil collector insert for the lubrication of a synchronisation device of a gear change device of a vehicle which allows efficient lubrication of the synchronisation device borne by the primary shaft even when the vehicle engine is idling or after starting with a cold engine, and which therefore eliminates the noise of the gear change device in these particular operating conditions and also helps to reduce friction and thus the wear of the synchronisation device. This object is achieved by the invention which relates to an oil collector insert for the lubrication of a synchroniser of a gear change device of a vehicle, this gear change device being of the type in which lubrication oil is housed in a box up to a predetermined level, with a primary shaft disposed above the oil level and a secondary shaft disposed parallel to the primary shaft and below the oil level, this primary shaft supporting a synchronisation device for at least one gear of the gear change device, this synchronisation device cooperating with a gear engagement fork and in turn comprising at least one engaging sleeve adapted to rotate rigidly with the primary shaft, this sleeve having an outer lateral surface disposed at least partly below the oil level, characterized in that this insert is secured detachably to the gear engagement fork and comprises an oil scraper blade cooperating with the outer lateral surface of the engaging sleeve, the oil scraper blade being shaped so as to cause the scraped oil to drip from the outer lateral surface of the engaging sleeve towards a respective engagement surface of the synchronisation device. The invention is set out in further detail in the following non-limiting description of an embodiment thereof made with reference to the accompanying drawings, in which: Fig. 1 is a front elevation of an oil collector insert in accordance with the invention mounted on a synchronisation device shown only partially; Fig. 2 is a front three-quarters elevation of a synchronisation device on which the insert of Fig. 1 is mounted; Fig. 3 is a lateral elevation of the synchronisation device of Fig. 2; and - Fig. 4 is a diagrammatic view of a gear change device. In Figs. 1 to 4, an oil collector insert 1 of the invention is mounted on a synchronisation device 2 of a gear change device 3 of a known vehicle, which is not shown for the purposes of simplicity. The gear change device 3 comprises a box 4 which houses lubrication oil 5 up to a predetermined level 6; the gear change device 3 further comprises a primary shaft 7 disposed above the level 5 and a secondary shaft 8 disposed parallel to the primary shaft 7 but, in contrast to the latter, below the level 6 of the oil 5. The primary shaft 7 bears an assembly of gears 9, while the secondary shaft 8 bears a corresponding assembly of gears 10. The primary shaft 7 bears, in addition to the gearing 9, the synchronisation device 2 for at least one gear of the gear change device 3; the synchronisation device 2 cooperates with a gear engagement fork 11 and in turn comprises at least one engaging sleeve 12 adapted to rotate rigidly in use with the primary shaft 7. The sleeve 12 is provided with an outer lateral surface 13 at least partly disposed below the level 6. In accordance with the invention, the insert 1 is secured detachably to the fork 11 and comprises an oil scraper blade 14 cooperating with the outer lateral surface 13 of the sleeve 12; the oil scraper blade 14 is shaped so as to cause the oil 15 scraped from the outer lateral surface 13 of the sleeve 12 to drip towards an engagement surface 16 of the synchronisation device 2. The oil scraper blade 14 has a width which is substantially greater than the width of the outer lateral surface 13 of the sleeve 12 and projects laterally from the surface 13 from the portion where the engagement surface 16 of the synchronisation device 2 is disposed. In a particular constructional embodiment of the invention, shown with particular reference to Figs. 2 and 3, the oil collector insert is U-shaped and is mounted astride the gear engagement fork 11; the insert 1 comprises a pair of opposite oil scraper blades 14 which are C-shaped and provided at respective opposite ends 19 of the insert 1. In use the blades 14 act on respective outer lateral surfaces 13 of a pair of opposite engaging sleeves 12. The fork 11 has, on an outer lateral surface 17, a pair of recesses 18 of semicircular shape which are adapted to cooperate in use with corresponding projections 21 which are also of semicircular shape provided on a lateral member 22 of the insert 1. In accordance with the invention, the lateral member 22 comes in use into contact with the outer lateral surface 17 of the fork 11 while the pair of projections 21 snap locks with the corresponding recesses 18 thereby locking the insert 1 astride the fork 11. The advantages provided by the invention are evident from the above description: the introduction of an oil scraper blade 14 on the engaging sleeve 13 of the synchronisation device 2 of the gear change device 3 allows efficient lubrication of the engagement surface 16 even when the vehicle engine is idling, the gears are in neutral or immediately after cold starting when the lubricating oil is particularly viscous; this lubrication eliminates the noise of the gear change device 3 in these particular operating conditions and also helps to reduce its wear as a result of friction.

Claims: An oil collector insert (1) for the lubrication of a synchronisation device (2) of a gear change device (3) of a vehicle, this gear change device (3) being of the type in which lubrication oil (5) is housed in a box (4) up to a predetermined level (6), with a primary shaft (7) disposed above the oil level (6) and a secondary shaft (8) disposed parallel to the primary shaft (7) and below the oil level (6), this primary shaft (7) supporting a synchronisation device (2) for at least one gear (9) of the gear change device (3), this synchronisation device (2) cooperating with a gear engagement fork (11) and in turn comprising at least one engaging sleeve (12) adapted to rotate rigidly with the primary shaft (7), this sleeve (12) having an outer lateral surface (13) disposed at least partly below the oil level (6); characterized in that this insert (1) is secured detachably to the gear engagement fork (11) and comprises an oil scraper blade (14) cooperating with the outer lateral surface (13) of the engaging sleeve (12), the oil scraper blade (14) being shaped so as to cause the scraped oil to drip from the outer lateral surface (13) of the engaging sleeve (12) towards a respective engagement surface (16) of the synchronisation device (2). An oil collector insert (1) as claimed in claim 1, characterized in that the oil scraper blade (14) has a width which is substantially greater than the width of the outer lateral surface (13) of the sleeve (12) and in that this blade (14) projects laterally from this surface (13) from the portion where the engagement surface (16) of the synchronisation device (2) is disposed. An oil collector insert (1) as claimed in claim 1 or 2, characterized in that the insert (1) is U-shaped and is mounted astride the gear selection fork (11) and comprises a pair of opposite oil scraper blades (14) provided at the location of respective opposite ends (19) of the insert (1), these blades acting in use on respective outer lateral surfaces (13) of a pair of opposite engaging sleeves (12). An oil collector insert (1) as claimed in claim 3, characterized in that the fork (11) has, on an outer lateral surface (17), at least two recesses (18) of semicircular shape adapted to secure the insert (1) in use. An oil collector insert (1) as claimed in claim 4, characterized in that it is provided with a lateral member (22) adapted to come in use into contact with the outer lateral surface (17) of the fork (11), this lateral member (22) being further provided with at least two projections (21) of substantially semicircular shape adapted to engage with the recesses (18) provided on the outer lateral surface (17) of the fork (11), these projections (21) and recesses (18) cooperating in a snap-locking manner in use. An oil collector insert (1) as claimed in any preceding claim, characterized in that the oil scraper blade (14) is substantially C-shaped, the blade (14) being secured laterally to one end (19) of the insert (1) and extending laterally in a snap-locking manner from one side facing towards the sleeve (12).

Inventors: MALUSARDI MARINO, MALUSARDI, MARINO
Applicants: FIAT AUTO SPA, FIAT AUTO S.P.A.
Application year: 1992
Main classification: F16H63
IPC codes: F16H57, F16H63