Zahnradfabrik Friedrichshafen, Ag.

Zf Friedrichshafen Ag

Bucksch, Manfred

Manfred Bucksch

Gert Bauknecht

Uwe Brendel

Peter Ziemer

Lutz Gärtner

Heribert Scherer

Rainer Pfalz

Karl-Heinz Bordowsky

The invention concerns an automatic gearbox, with a drive input shaft () which is connected to a shiftable reduction planetary gear set (), with a drive output shaft () which is connected to a shiftable main planetary gear set (), and with five shifting elements (A to E) by the selective closing of which six forward speeds can be engaged without range change. An output element of the reduction planetary gear set () can be connected via a first shifting element (A) to a first input element of the main planetary gear set () and via a second shifting element (B) to a second input element of the main planetary gear set (). The drive input shaft () can be connected via a fifth shifting element (E) to a third input element of the main planetary gear set (). A solar gear wheel () of the reduction planetary gear set () is in particular fixed on a cylindrical projection () of a gearbox housing wall (). The reduction planetary gear set () is made as a Plus transmission with inner and outer planetary gear wheels (), whose webs () are connected to one another.

Six-speed automatic gearbox

The multi-step automatic transmission with a number of clutches and brakes which at least partly are designed as wet-running, multi-disk clutches wherein with each clutch is associated a hydraulic piston ( ), is provided with a baffle plate ( ) for the fluid within or outside the clutch for adapting the shifting forces to low torques so that an additional pressure chamber ( ) is formed which does not impair the total stroke of the piston ( ).

Variable gear ratio transmission

Pump drive for a motor vehicle automatic transmission

Transmission for a motor vehicle

Compact construction for transversely mounted transmission

A planetary-gear assembly has a planet gear carrier constituted by a pair of axially spaced carrier plates bridged by a plurality of axially extending pins each carrying a respective planet gear by means of a respective bearing. An adjacent member rotatable independently of the planet carrier forms with the planet carrier an annular chamber centered on the axis. This annular chamber is closed axially by the one carrier plate and the adjacent member and is closed radially outwardly by a seal ring engaging between this one carrier plate and the adjacent member. Each of the pins is formed with a throughgoing passage opening axially into this annular chamber and radially at the respective bearing. Liquid lubricant is fed to the chamber radially inwardly of these passages so as the assembly rotates the lubricant will be forced radially outwardly, filling the radial outward portion of the chamber and forcing the lubricant through the passage to the bearings.

Lubricating arrangement for planet-gear bearing

A clutch or brake cylinder has an annular working space accommodating an annular piston which confronts a stack of interleaved friction plates adapted to couple the cylinder to a coaxial member rotatable relatively thereto, the piston being displaceable by fluid pressure toward the stack against the force of a Belleville spring. This piston occupies only part of the working space so as to leave an annular clearance in which an ancillary sealing ring is independently slidable. When fluid pressure is applied, part of that pressure pushes the sealing ring against the Belleville spring and lifts it off the piston which then can exert its full force upon the stack of friction plates. Extraction of the cylinder from a surrounding housing enables the piston and the sealing ring to be replaced by a larger piston, filling the entire cross-sectional area of the working space, if a greater coupling pressure is to be exerted.

Piston-and-cylinder assembly for hydraulic disk clutch or brake

A pair of hydraulic clutches, serving to connect an input shaft with either of two nested output shafts coaxial therewith, comprise a common die-cast annular carrier in the form of a generally cylindrical sleeve whose inner and outer surfaces are integrally formed with peripherally spaced first and second ribs for the guidance of a first and a second set of annular friction foils, respectively. The carrier has an inner radial flange forming an abutment for one of the friction foils of the first set, the second ribs being axially offset from the first ribs and extending beyond that flange in the form of peripherally separated prongs. The inner sleeve surface diverges outwardly from the region of the flange, with a slight draft as needed for casting; at its wider end the sleeve is fastened to a similarly produced first clutch housing accommodating a first piston normally held spaced apart from the first friction foils by a Belleville spring inserted between the sleeve and that clutch housing. A second clutch housing envelops the part of the sleeve carrying the second friction foils and accommodates a second piston coacting with the latter foils. The flange has gaps open toward the spaces between the second ribs to facilitate the circulation of fluid along the sleeve from a supply channel within the inner output shaft to an outlet port of a surrounding transmission housing.

Clutch assembly for planetary-gear trains

A planetary-gear coupling between a torque converter and a load, such as an automotive engine, comprises a transmission housing with two fluidically actuated clutches serving to couple an input shaft with either of two coaxial output shafts carrying respective sun gears of two planetary-gear trains. The input shaft, driven by the rotor of the torque converter, and a surroundng tube, secured to its stator, define between them an annular clearance bounded by two sealing rings, one of these rings being interposed as a journal bearing between the tube and a first clutch housing positively connected with the input shaft. The annular clearance can be pressurized from the output of a fluid pump and communicates through a bore in the first clutch housing with the interior thereof which contains a first piston displaceable to consolidate that housing with the inner output shaft. The outer output shaft, having an end splined to a surrounding second clutch housing, is journaled in a surrounding annular bearing within a transverse partition of the transmission housing, this partition having a central annular boss defining with a hub of the second clutch housing a ring channel communicating with a radial bore in the partition which can also be pressurized by the pump. The ring channel is open toward a longitudinal inner groove of the hub of the second clutch housing communicating with the interior of that housing through another bore, a second piston in this clutch housing being displaceable to consolidate same with the input shaft.

Speed-changing system with two fluid-actuated clutches

A planetary-gear coupling between a torque converter and a load, such as an automotive engine, comprises a transmission housing with two fluidically actuated clutches serving to couple an input shaft with either of two coaxial output shafts carrying respective sun gears of two planetary-gear trains. The input shaft, driven by the rotor of the torque converter, and a surrounding tube, secured to its stator, define between them an annular clearance bounded by two sealing rings, one of these rings being interposed as a journal bearing between the tube and a first clutch housing positively connected with the input shaft. The annular clearance can be pressurized from the output of a fluid pump and communicates through a bore in the first clutch housing with the interior thereof which contains a first piston displaceable to consolidate that housing with the inner output shaft. The outer output shaft, having an end splined to a surrounding second clutch housing, is journaled in a surrounding annular bearing within a transverse partition of the transmission housing, this partition having a central annular boss defining with a hub of the second clutch housing a ring channel communicating with a radial bore in the partition which can also be pressurized by the pump. The ring channel is open toward a longitudinal inner groove of the hub of the second clutch housing communicating with the interior of that housing through another bore, a second piston in this clutch housing being displaceable to consolidate same with the input shaft.

A centrifugal governor on a rotating shaft has a mounting rigid with that shaft, the latter being journaled in a housing wall from which a stationary hub extends into a central bore through which a hydraulic fluid is admitted to an inlet port of a valve controlled by the governor, the outlet port of that valve communicating with a clearance provided between the hub and the shaft which opens into an outgoing channel in the hub.

Growing community of inventors

Friedrichshafen, Germany

Manfred Bucksch