Abstract: A suspension system with an oscillating, rigid axle, particularly for tractors, is described; the axle is supported on a sub-frame with oscillating arms which in turn can be mounted for oscillating on a load-bearing structure of the tractor by suspension means interposed between the axle and the load-bearing structure, the sub-frame comprising at least two pairs of arms arranged so as to form a so-called pantograph-like kinematic linkage.

Abstract: A phase variator including a piston actuator slidable between two travel limit positions as a result of the supply of a flow of pressurized fluid to at least one chamber of the variator. Valves are provided in the variator for choking the flow associated with the at least one chamber so as to avoid axial end contact of the piston and casing and axial end contact of the piston and hub.

Abstract: In a braking unit of the SAHR type comprising a braking pack with disks and counter-disks, a resilient system for compressing the pack with a braking load sufficient for parking braking, a first hydraulic system for exerting on the resilient system a contrary load sufficient to cancel out its effect, a second hydraulic system acting on the pack to compress it with a braking load sufficient for service braking, both hydraulic systems share a single piston acting on one side on the pack and on the other side on the resilient system.

Abstract: In a steering drive axle, particularly for agricultural tractors, the transverse transmission members (16-20) which bring the drive from a central differential (12) to the wheel hubs (13a) comprise a half-shaft portion (18) having a first end connected to a universal joint (17) at the output from the differential (12), and a second end connected to a constant-velocity joint (19) fixed for rotation with a respective hub (13a). The half-shaft portion (18) is mounted for rotating on a support (22) connected (23) to articulated suspension members (14, 15) in a manner such as to support the outer end of the half-shaft portion (18) and the inner end of the constant-velocity joint (19).

Abstract: A sprung axle is described comprising a central body which is suitable for attachment in a fixed or oscillating manner to a supporting structure of the vehicle and to which are connected two side bodies by means of respective independent-wheel suspensions including suspension arms articulated by one of their ends to the respective side body and by the opposite end to the central body and also shock-absorbing and/or spring-suspension means between the corresponding side body and the central body, the shock-absorbing and/or spring-suspension means and the suspension arms being otherwise substantially detached from the supporting structure of the vehicle.

Abstract: In a mechanical device for changing the phase relationship between the engine shaft and a camshaft of an internal combustion engine, in which the phase change is achieved by a change in the angular position of a body kinematically connected to the engine shaft relative to that of a shaft kinematically connected to the camshaft by the movement of a piston and of an auxiliary annular element which are spaced apart axially and are interposed between the body and the shaft to which they are coupled by intermeshing teeth, a stop is provided for limiting the axial travel of the auxiliary annular element, advantageously stopping the piston owing to engagement in the teeth of the shaft and of the body.

Abstract: The single-acting phase variator includes a piston actuator movable towards an actuate position, as a result of the admission of a pressurized fluid to a supply chamber through a distribution and discharge duct opening in the chamber against the force of a spring. A valve is provided in the variator for connecting the distribution and discharge duct alternatively to a feed duct for the pressurized fluid or to a discharge opening for the rapid discharge of the fluid from the chamber.

Abstract: The friction clutch unit described has two clutches, of which the second is normally disengaged. Each clutch comprises a clutch disc disposed coaxially between a pressure plate and a friction surface, the arrangement being such that the first and second pressure plates are both disposed between the clutch discs and a lever linkage for operating the second clutch acts on the corresponding pressure plate so as to move it away from the other pressure plate during the operative engagement of the respective clutch.

Abstract: A timing variator disposed between a crankshaft and a camshaft of an internal combustion engine includes a body portion connected to the crankshaft and a hub connected to the camshaft. A piston is interposed between the body and the hub and coupled thereto by helical gearing for changing the angular position of the body relative to the hub. A torsion member is connected between the body and the hub for producing a torque therebetween and/or a braking device is disposed between the body and the hub to brake relative movement therebetween.

Abstract: A timing variator which is constructed to provide at least three predetermined different relative angular settings of the camshaft and the timing system of an internal combustion engine; the variator comprises a piston actuator slidable inside a space against a spring as a pressurized fluid is delivered into a supply chamber thereof. When the piston is to be stopped at a position intermediate to two end-of-stroke positions, in order to obtain an intermediate timing setting, pressurized fluid is delivered behind the piston, thereby producing an additional thrust concurrent with the spring thrust and partly balancing out the pressure of the medium being delivered into the supply chamber.

Abstract: A steering axle is disclosed which comprises a girder having a respective wheel hub spindle hinged to its opposed ends by means of two hinges. An elastic element, such as a Belleville washer, is fitted between the elements of one of the hinges for adjusting the backlash between the girder and the spindle.

Abstract: An axle is disclosed which comprises a beam designed for conventional installation on the load-bearing structure of a vehicle, and has, journalled on its opposite ends, road wheel hubs subject to be steered through a steering actuator and being interlinked by a bevel-gear steering drive, such that their relative angular movements can be synchronized to suit pre-determined transmission parameters; the steering actuator is fully supported on the beam and has a stationary part which is rigid with the beam and independent of the load-bearing structure of the vehicle and a moveable part which is connected to the wheel hubs through the steering drive.

Abstract: The transmission includes a hydraulically operated actuator for selectively controlling a locking mechanism for a differential mechanism interconnecting a motion input shaft and at least two motion output shafts. The lubricant for the differential mechanism is supplied by a pump to an actuator for the lock device with the pump being driven from the motion input shaft. In one embodiment, the pump and the actuator are disposed in a support for the differential mechanism. In a second embodiment, the pump is mounted on the housing and is provided with a reciprocating piston driven by a rotatable cam mounted for rotation with the differential casing. The plunger is biased in one direction by a spring in such a manner that the plunger is driven for a suction stroke by the cam and for a delivery stroke by the spring.

Abstract: A steering axle includes a beam pivotally mounted on a load-bearing structure of a vehicle. A steering actuator is mounted on the beam and includes a casing which provides a journal formation for pivotally mounting the beam on the load-bearing structure.

Abstract: A multiple disk brake is disclosed which includes a pusher movable toward and away from a friction surface, spring means urging the pusher away from the friction surface, at least one bush slidable to an interference fit within a corresponding seat of the pusher to limit a return stroke of the latter, at least one corresponding link for limiting to a predetermined length the movement of the bush relatively to a brake abutment surface, which comprises a spacer between a head of the link and the abutment surface. Thus, the effect of the machining tolerances of the link components on restoration of an optimum clearance between the pusher and the friction surface is attenuated.

Abstract: The solution described enables the provision of a timing variator with internal circulation of the working servo-medium, while ensuring firm retention and centering ability relatively to the driving shaft (A).

Abstract: An adjustable gauge steering axle is disclosed which comprises an adjustable length beam and a steering control including a double-acting, dual piston rod hydraulic cylinder. Each piston rod of the hydraulic cylinder is connected to a corresponding steering arm through a respective strut which is adjustable telescopingly in length; a swivel joint intervenes between the rod and the strut.

Abstract: A self-locking differential gear includes a gear carrier on which two crown wheels are journalled and a clutch disposed between each crown wheel and the gear carrier to selectively render a corresponding axle shaft rotatable with the gear carrier. Each crown wheel is comprised of a ring wheel rotatable with an axle shaft and a ring gear in meshing engagement with the plant gears. A clutch operating device includes first and second engagement members shiftable angularly relative to each other and being respectively rotatable with the ring gear and the corresponding axle shaft. The engagement members are operative to engage a corresponding clutch when shifted angularly with respect to each other in at least one of the two directions of rotation of the corresponding axle shaft, thereby providing for an effective locking of the differential gear even on the occurrence of a significant difference in the torque being transferred from each axle shaft.

Abstract: A differential gear mechanism for motor vehicles, which is effective as well as quite simple construction-wise and low in production cost, comprises a differential gear case made rotatively rigid with a ring gear, a tubular body mounted within the case with a predetermined amount of angular backlash and being rotated thereby, two coaxially aligned sleeves attached to the ends of respective axle shafts and fitting rotatably within the tubular body, and for each sleeve, two freewheel devices arranged to alternately act between the tubular body and the sleeve and a change-over mechanism for activating either of the freewheel devices according to the running direction, in forward or reverse gear.