Zf Friedrichshafen Ag

Markus Herrmann

Thilo Schmidt

Georg Gierer

Alexander Haberstock

Anton Fritzer

Armin Haugg

Josef Haupt

Christian Popp

Rainer Grundler

Tobias Rolser

Stefan Beck

Peter Ziemer

Christian Sibla

Wolfgang Grosspietsch

Angelika Ebert

Bernd Allgaier

Christoph Margraf

Peter Frey

Andreas Orlamünder

Thomas John

Tobias Miller

Andreas Ratte

Monika Rößner

Hans-Joachim Martin

Stefan Brom

Arthur Schröder

Eberhard Biermann

Gerhard Hermann Martin

Stephan Stroph

Dirk Winkler

Ulrich Doerr

Oliver Angele

Maik Wiesner

Valentine Vincent

Christian Staiger

Horst Roegner

Florian Lanz

Dietmar Gehring

Marcel Gutzeit

Ernst Bartels

Ahmed Mouhcine

Robert Erath

Michael Kneuer

Christian Schupp

Andre Willburger

Stefan Schmidt

Adriano Handrich

Martin Kaufmann

Christian Schneider

Willi Giesenkirchen

Patrick Gutmann

Saturation of a secondary system pressure circuit () of a hydraulic system () of a motor vehicle transmission is earlier, in that an excess amount of oil from a primary system pressure circuit () of the hydraulic system () is not directed to a suction charging (), but rather into the secondary system pressure circuit (). This can take place via a system pressure valve () for the primary system pressure circuit (), which is configured for this function.

System pressure valve for a hydraulic system of a motor vehicle transmission

A drive train unit (HY, G) for a motor vehicle includes a first shaft (TW), a second shaft (PW), and a third shaft (AN). The first shaft (TW) is rotatably mounted at an inner diameter of the second shaft (PW) with a first bearing (L). The second shaft (PW) is rotatably mounted at an inner diameter of the third shaft (AN) with a second bearing (L, L). A lube oil feed to the first bearing (L) and the second bearing (L, L) takes place through a bore hole (B) arranged in the first shaft (TW). An oil baffle chamber (S) is formed at an inner surface of the second shaft (PW) and includes a first outflow (S) and a second outflow (S). A drive train for a motor vehicle may include such a drive train unit (HY, G).

Drive train unit and drive train for a motor vehicle

A hydraulic control unit () for an automatic transmission of a motor vehicle includes a volumetric flow rate control valve (). The hydraulic control unit () is configured for delivering hydraulic fluid to an inlet () of the volumetric flow rate control valve (). An outlet () of the volumetric flow rate control valve () is connected to a torque converter torus of the automatic transmission. In addition, the volumetric flow rate control valve () is configured for directing the hydraulic fluid across an orifice (), so that the pressure of the hydraulic fluid is reduced and a constant flow of hydraulic fluid is feedable to a torque converter torus.

Hydraulic control unit for an automatic transmission of a motor vehicle

A valve system for a hydraulic emergency driving gear function of a hydraulic control unit for a motor vehicle automatic transmission includes a position valve () with a first piston slide () and an electromagnetic pressure regulator () having a decreasing characteristic curve. The first piston slide () is preloaded in a first position. When the first piston slide () is in a second position, the electromagnetic pressure regulator () is configured for connecting a system pressure-carrying line () of the motor vehicle automatic transmission to a first emergency driving gear clutch () of the motor vehicle automatic transmission and to a second emergency driving gear clutch () of the motor vehicle automatic transmission, whereby the first emergency driving gear clutch () and the second emergency driving gear clutch () are actuated, so that an emergency driving gear of the motor vehicle automatic transmission is engaged.

Valve system for a hydraulic emergency travel gear function of an automatic transmission for a motor vehicle

A cooling prioritization valve () for a hydraulic system () of a motor vehicle transmission () includes a valve housing (), a valve slide (), an inlet (), an outlet (), and a further outlet (). A secondary system pressure circuit () of the hydraulic system () can be connected to the inlet (), a cooler () can be connected to the outlet () or to the further outlet (), and a suction loading () can be connected to the outlet () or to the further outlet (). In a starting position, the inlet () is not connected either to the outlet () or to the further outlet (). In a first control position, the inlet () is connected to the outlet (). In a second control position, the inlet () is connected to the outlet () and the further outlet ().

Cooling-prioritization valve for a hydraulic system of a motor vehicle transmission

A hydraulic system for a transmission of a motor vehicle, the system having first and second pumps for conveying hydraulic fluid into primary and/or system-pressure circuits so that an intended pressure prevails in the circuits. The system further including liquid retention means preventing a flow of hydraulic fluid conveyed by the second pump from being conducted through the first pump when the first pump is not conveying and the second pump is conveying, and preventing a flow of hydraulic fluid conveyed by the first pump from being conducted through the second pump when the second pump is not conveying and the first pump is conveying. The system additionally including a sailing-mode lubricating valve for controlling, by an open-loop system, a flow rate of hydraulic fluid conveyed by the second pump into the primary and/or secondary system-pressure circuits such that the intended pressure is set in the system-pressure circuits.

Hydraulic system for a transmission of a motor vehicle

A parking lock having a locking pawl engageable into a parking interlock gear, a connecting rod with an interlocking element to prevent the parking lock from disengaging when in the locked condition, a spring for engaging the parking lock, a hydraulically actuatable actuator for disengaging the parking lock, and an emergency release device for emergency disengagement of the parking lock. The piston is articulatedly connected to a first disk rotatably mounted on a selector shaft, a second disk connected to the selector shaft in a torsion-proof manner is articulatedly connected to the connecting rod, the spring is tensioned between the transmission housing and the second disk, and the emergency release device is connected to the selector shaft in a torsion-proof manner. The first disk is operatively connected to the second disk such that rotation of the second disk by the emergency release device does not rotate the first disk.

Parking lock of an automatic transmission for a vehicle

A greaser for a transmission includes a shaft () having an axial bore () and a plurality of axially spaced radial bores (). Each of at least one tube () is inserted into a respective one of the axially spaced radial bores () and extends radially inwardly into the axial bore () beyond a circumferential surface () of the axial bore () that is adjacent the respective one of the axially spaced radial bores (). Each of the at least one tube () includes a slot () at a tube end () facing a central axis () of the shaft (). The slot () of each of the at least one tube () extends along a central axis () of the respective tube () into an interior space of the axial bore ().

Lubricating device for a transmission, and transmission comprising said lubricating device

A system for locking and releasing a shifting position of a shifting element that is hydraulically actuatable by an actuating pressure is provided. The shifting element is arranged coaxially with a transmission shaft. The system includes a stop valve. The stop valve is subjectable to a control pressure that is separate from the actuating pressure of the shifting element. The stop valve is arranged radially inside the shifting element in the transmission housing.

Assembly for blocking and enabling a shifting position of a shifting element

An electrohydraulic transmission control system () includes a parking lock valve (). The electrohydraulic transmission control system () is configured such that, during normal operation of the electrohydraulic transmission control system () in which at least one electrohydraulic pressure adjuster (EDSSYS) is actuatable with current, the parking lock valve () can be held in a defined operating state in which an actuation pressure (p_sys) acts on a parking lock cylinder () above a normal pressure level. The electrohydraulic transmission control system () is configured such that, during emergency operation of the electrohydraulic transmission control system () in which the at least one electrohydraulic pressure adjuster (EDSSYS) is not fed with current and the actuation pressure (p_sys) is at least temporarily set to an emergency pressure level higher than the normal pressure level by the at least one pressure source (), a pressure level of the actuation pressure (p_sys) that holds the parking lock valve () in the defined operating state corresponds at least approximately to the emergency pressure level.

Hydraulic valve system of a parking lock device

An electrohydraulic transmission control system having a parking lock valve by which a parking lock cylinder of a parking lock device can be charged with an actuation pressure adjustable in an operating-state-dependent manner by at least one pilot pressure adjustable in the region of an electrohydraulic pressure adjuster and/or one pressure source. Above a defined actuation pressure level, the parking lock valve is held in a defined operating state in which the actuation pressure can be applied to the parking lock cylinder. The actuation and pilot pressures can be applied to a valve device such that when the actuation and pilot pressure levels approximately correspond to one another, the region of the control system which conducts the actuation pressure is operatively connected, upstream of the parking lock valve, to a pressure region in the region of the valve device with a pressure lower than the defined actuation pressure level.

Hydraulic valve system for actuating a parking lock device

A hydraulic system for an automatic transmission a valve slide longitudinally adjustable in a valve housing between a first axial position and a second axial position such that a plurality of valve seat pockets are selectively brought into operative connection with each other. A control surface of the valve slide, first and second additional control surface of the valve slide and a spring of a parking brake valve are matched to one another such that the total actuating force applied to the slide valve displaces the slide valve to the first axial position when an actuating pressure of the parking brake unit, a pressure signal at the control surface of the valve slide and an additional pressure signal at the second additional control surface of the valve slide are applied.

Hydraulic system of an automatic transmission with multiple valve devices

A drag torque reduction device for an automatic transmission includes a hydraulic controller with a radiator. In one embodiment, the drag torque reduction device also includes a parallel connection of a pressure relief valve, a constant aperture and a temperature-dependent, switchable aperture positioned upstream of the radiator. In another embodiment, the drag torque reduction device includes an overflow cooling oil diversion with a temperature-dependent, switchable aperture and a pressure relief valve that is positioned upstream of the radiator.

Device reducing drag loss in an automatic transmission

When the stop valve is in a first shifting position, a torque-transferring shift element is sealed tight against the rest of a hydraulic system by a stop valve, such that the actuating pressure enclosed in the shift element remains essentially constant or does not decrease. The stop valve is formed and arranged in the hydraulic system such that the stop valve is held in the first shifting position by the force of a barrier pressure generated by the pump, and, upon a standstill of the pump or falling below a certain value of the pressure generated by the pump, the stop valve is automatically displaceable at least through the action of the trapped shift element pressure into a second shifting position, in which the respective shift element is connected to the rest of the hydraulic system and the shift element is open.

Hydraulic control device for an automatic transmission

A hydraulic control device for an automatic transmission includes a shut-off valve arranged between a first pressure adjusting device and a respective shifting element cylinder of a plurality of shifting elements. In the first shifting position of the shut-off valve, the first pressure adjusting device is hydraulically connected to the respective shifting element cylinder through the shut-off valve. In the second shifting position of the shut-off valve, the shifting element cylinder is sealed by the shut-off valve relative to the first pressure adjusting device. The shut-off valve is an releasable check valve. The releasable check valve includes a check valve and an unblocking device. The unblocking device is actuatable by a control pressure from a second pressure adjusting device.

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Scheidegg, Germany

Markus Herrmann