ZF Friedrichshafen

About: ZF Friedrichshafen is a company organization based out in Friedrichshafen, Germany. It is known for research contribution in the topics: Clutch & Drive shaft. The organization has 5684 authors who have published 11141 publications receiving 44651 citations.

Active damping of drive train oscillations for an electrically driven vehicle

Abstract: A problem encountered with electrically driven vehicles are resonances in the drive train caused by elasticity and gear play. Disadvantageous effects caused by this are noticeable vibrations and high mechanical stresses due to torque oscillations. The oscillations can be damped using a control structure consisting of a nonlinear observer to estimate the torque in the gear and a controller, which computes a damping torque signal that is added to the driver's demand. The control algorithm was implemented in the existing motor control unit without any additional hardware cost. The controller was successfully tested in a test vehicle. The resonances can essentially be eliminated. The controller copes satisfactorily with the backlash problem.

Multi-stage transmission

Abstract: The invention relates to a multi-stage transmission provided with an input shaft (3), which is connected to a shiftable front-mounted planet gear set (10), with an output shaft (4), which is connected to a shiftable main planet gear set (20), and with a number of shifting elements (A to F) whose selective closing enables the shifting of at least six forward speeds without range shift. An output element of the front-mounted planet gear set (10) can be connected to a first input element of the main planet gear set (20) via a first shifting element (A) and can be connected to a second input element of the main planet gear set (20) via a second shifting element (B). The input shaft (3) can be connected to a third input element of the main planet gear set (20) via a fifth shifting element (E). Preferably, a sun gear (11) of the front-mounted planet gear set (10) can be fixed via a sixth shifting element (F) mounted on the side of the front-mounted planet gear set (10) facing away from the main planet gear set (20). The front-mounted planet gear set (10) is provided in the form of a Plus gearing having inner and outer planet gears (12, 13) whose webs (15, 16) are interconnected.

Pressure regulating valve

Abstract: Pressure regulating valve comprising a connection for a pressure line (P), a connection for a working line (A), a connection for an outlet line (T) communicating with the ambient pressure and at least two diaphragm stages with defined or definable drag, the two diaphragm stages being connected to each other in a variable manner and subject to mechanical or hydraulic action according to the principle of the hydraulic half bridge. The two variable diaphragm stages are provided as the inlet and outlet diaphragms of a pressure regulating chamber (7) and each has a sealing element, said sealing element (5) of the inlet diaphragm (3) is designed as ball, or calotte, or truncated cone, or cylinder and/or the sealing element of the outlet diaphragm is designed as ball, or calotte, or truncated cone, or cylinder.

Multi-speed transmission

Abstract: The present disclosure provides a multiple speed transmission having an input member, an output member, a plurality of planetary gearsets, a plurality of interconnecting members and a plurality of torque-transmitting mechanisms. Each of the plurality of planetary gearsets includes a sun gear, a ring gear, and a carrier member with pinion gears. The input member is selectively interconnected with at least one member of one of the plurality of planetary gear sets, and the output member is continuously interconnected with another member of one of the plurality of planetary gear sets. At least ten forward speeds and one reverse speed are achieved by the selective engagement of the plurality of torque-transmitting mechanisms.