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DE-102024132815-A1 - drive device

DE102024132815A1DE 102024132815 A1DE102024132815 A1DE 102024132815A1DE-102024132815-A1

Abstract

Drive device comprising at least one drive unit with an output shaft (3) and a drive shaft (5) coupled to it via a vibration damping device (4), wherein the vibration damping device (4) comprises a housing (20) containing an arc spring arrangement comprising several arc springs (18), which is coupled to the drive shaft (5) via a hub flange (22), and a flange disk connected to the arc springs (18) and attached to one end of the output shaft (3), wherein an additional mass in the form of a flywheel (8) is assigned to the other end of the output shaft (3), characterized in that the flywheel (8) is part of a position detection device (9) for detecting the rotational position of the output shaft (3).

Inventors

  • Richard Unterreiner
  • Rainer Hannappel

Assignees

  • Schaeffler Technologies AG & Co. KG

Dates

Publication Date
20260513
Application Date
20241111

Claims (6)

  1. Drive device comprising at least one drive unit with an output shaft (3) and a drive shaft (5) coupled to it via a vibration damping device (4), wherein the vibration damping device (4) comprises a housing (20) containing an arc spring arrangement comprising several arc springs (18), which is coupled to the drive shaft (5) via a hub flange (22), and a flange disk connected to the arc springs (18) and attached to one end of the output shaft (3), wherein an additional mass in the form of a flywheel (8) is assigned to the other end of the output shaft (3), characterized in that the flywheel (8) is part of a position detection device (9) for detecting the rotational position of the output shaft (3).
  2. drive device according to Claim 1 , characterized in that the flywheel (8) has a structure (25) that can be detected by a positionally fixed sensor element (10) of the position detection device (9).
  3. drive device according to Claim 2 , characterized in that the structure (25) is realized in the form of elevations and/or depressions arranged equidistantly around the circumference of the flywheel (8).
  4. drive device according to Claim 3 , characterized in that the structure (25) is realized in the form of a toothing (26) or openings or axially extending fingers.
  5. Drive device according to one of the preceding claims, characterized in that the at least one drive unit is an internal combustion engine (2).
  6. Drive device according to one of the preceding claims, characterized in that it is a hybrid drive comprising a further drive unit in the form of an electric machine (12), wherein a coupling device (15) is provided, via which the internal combustion engine (2) can be reversibly coupled to the drive shaft (5).

Description

The invention relates to a drive device comprising at least one drive unit with an output shaft and a drive shaft coupled to it via a vibration damping device, wherein the vibration damping device has a housing containing an arc spring arrangement comprising several arc springs, which is coupled to the drive shaft via a hub flange, and a flange disk connected to the arc springs, which is attached to one end of the output shaft, wherein an additional mass in the form of a flywheel is assigned to the other end of the output shaft. Such a drive device is, for example, made of DE 10 2017 127 525 A1 This is known, for example, in the form of a hybrid drive. In motor vehicles, such as those with a hybrid drive comprising an internal combustion engine and an electric motor, the requirement is to transmit torque, particularly that generated by the internal combustion engine, to a transmission with minimal vibration. This is achieved using a torque transmission device, which is designed as or includes a vibration damping device, and via which the sometimes oscillating torque supplied by the internal combustion engine is transmitted in a damped manner to a drive shaft leading to a transmission. Such a vibration damping device comprises an input part and an output part, which are rotatable relative to each other to a limited extent, counteracting the action of circumferentially acting energy storage devices designed as arc springs, thereby absorbing kinetic energy and releasing it back into the drivetrain. Such a vibration damping device can either be designed in the form of a conventional dual-mass flywheel, consisting of a primary part with associated arc springs, which is bolted to the output shaft of the drive unit, i.e., for example, the crankshaft of the internal combustion engine. The secondary part is connected to the drive shaft, i.e., the transmission input shaft, via a suitable non-rotatable connection, usually a hub. Alternatively, as shown in DE 10 2017 127 525 A1 As is known, a vibration damping device known as a "reverse damper" can also be used, which is reversed in its construction or arrangement of the primary and secondary parts. In such a design, the housing containing the arc springs is the secondary part, which is coupled to the drive shaft via a hub flange. The primary part, connected to the output shaft, i.e., the crankshaft, is designed as a simple flange disk that is connected to the arc springs via corresponding drivers. To compensate for the relatively low moment of inertia of the vibration damping device designed as a "reverse damper" or of the primary part, and to improve the isolation of vibrations of the output shaft, i.e., the crankshaft, a flywheel is fixed to the other side of the output shaft, as shown in DE 10 2017 127 525 A1 known. Furthermore, it is known to determine the position of the output shaft, i.e., the crankshaft, in order to use the measured values to determine the ignition timing. This value can then be used to control the fuel injection and other parameters that allow for the optimized operation of the internal combustion engine. For this purpose, it is necessary to precisely determine the crankshaft position, which in turn indicates the position of the individual pistons. This allows the control unit to determine when the first cylinder is at top dead center in order to precisely determine the ignition timing and firing order. A position detection device, usually designed as an incremental encoder, is used for this purpose. This typically includes a encoder gear with a sufficiently large diameter, which is coupled to the crankshaft, and a suitable incremental sensor that is fixed in position and scans the rotating encoder gear. This sensor is usually designed as a correspondingly large disc, i.e., with a correspondingly large diameter. However, due to the high inertia of the encoder disc compared to the low inertia of the vibration damper, such a large encoder disc can only be used in a lightweight design or with a very small diameter in conjunction with a vibration damper designed as a "reverse damper". The invention therefore addresses the problem of providing an improved drive device in comparison. To solve the problem, in a drive device of the type mentioned at the outset, it is provided according to the invention that the flywheel is part of a position detection device for detecting the rotational position of the output shaft. According to the invention, the flywheel, which is provided to improve vibration isolation, is also used as a multifunctional component for the position detection device and is therefore also part of it. On the one hand, the flywheel is dimensioned accordingly to the requirements of the vibration damping device, i.e., its mass is dimensioned accordingly. On the other hand, it is rotationally fixed to the output shaft, i.e., for example, the cable. The flywheel is connected to the internal combustion engine's crankshaft, meaning it rotates