Coupling device

Abstract

Coupling device for coupling and decoupling a drive shaft (12) to an output shaft (14) of a drive train of a motor vehicle, with a sliding sleeve (16) mounted displaceably in the axial direction for the positive transmission of a torque from the drive shaft (12) to the output shaft (14); an actuator (18) for actuating the sliding sleeve (16) in the axial direction into at least a first position and a second position; a driver (20) coupled to the sliding sleeve (16) and mounted so as to be displaceable in the axial direction; a sensor unit (22) for measuring the axial displacement of the driver (20); wherein the axial position of the sliding sleeve (16) can be determined by measuring the axial displacement of the driver (20), characterized in that the actuator (18) has at least one recess extending in the axial direction for receiving and guiding the driver (20) in the axial direction, , wherein the actuating elements (30) of the actuator (18) are arranged in a form-fitting manner on the sliding sleeve (16).

Description

[0001] The following embodiments relate to a coupling device for coupling and decoupling a drive shaft to an output shaft of a motor vehicle drive train, by means of which the coupling position of the coupling device can be precisely determined in a cost-effective and space-saving manner. Furthermore, the following embodiments relate to a drive train for a motor vehicle, comprising a drive shaft, an output shaft, and a coupling device.

[0002] A drivetrain refers to the components of a motor vehicle through which torque is transferred from an engine to the wheels. The drivetrain typically includes components such as transmissions, shafts, differentials, etc. Particularly in motor vehicles, it is advantageous in certain driving situations to deactivate certain components of the drivetrain, i.e., to decouple them from the other components, so that the transmission of rotational movement or torque to the deactivated components can be avoided. This prevents energy losses due to the lack of rotational movement of the deactivated components.

[0003] For such coupling or decoupling, a coupling device is provided, which is connected or connectable to the input shaft on the one hand and to the output shaft on the other. Such a coupling device is often also referred to as a disconnect unit (DCU). The input shaft is understood to be the shaft connected or connectable to the coupling device, which is arranged on the engine side thereof. The output shaft is understood to be the shaft connected or connectable to the coupling device, which is arranged on the wheel side thereof. Torque is transmitted between these shafts when the coupling device is in a coupled state or when the sliding sleeve is in the coupled position.The position of the sliding sleeve, or rather the determination of the axial position of the sliding sleeve within the coupling device, is of crucial importance and makes a significant contribution to the operational reliability of the coupling device. The axial position of the sliding sleeve is sometimes determined by determining the position of the actuator within the coupling device.

[0004] As prior art, reference is made, for example, to DE 10 2012 210 298 A1 and DE 103 33 948 A1, each of which discloses a coupling device according to the preamble of patent claim 1.

[0005] Further prior art is referred to DE 10 2019 132 591 A1.

[0006] There is a constant need to increase the operational reliability of coupling devices while simultaneously reducing manufacturing costs and the space required.

[0007] Based on this situation, the present task is to identify measures that enable a safe, cost-effective and space-saving coupling device.

[0008] The present problem is solved by the features of the independent main claim. Advantageous embodiments are specified in the subclaims. To the extent technically feasible, the teachings of the subclaims can be combined arbitrarily with the teachings of the main and subclaims.

[0009] The problem is therefore solved by a coupling device for coupling and decoupling a drive shaft to an output shaft of a drive train of a motor vehicle, comprising a sliding sleeve mounted so as to be displaceable in the axial direction for the positive transmission of a torque from the drive shaft to the output shaft; an actuator for actuating the sliding sleeve in the axial direction into at least a first position and a second position; a driver coupled to the sliding sleeve and mounted so as to be displaceable in the axial direction; a sensor unit for measuring the axial displacement of the driver; wherein the axial position of the sliding sleeve can be determined by measuring the axial displacement of the driver.

[0010] The axial displacement of the sliding sleeve allows for direct or indirect coupling and decoupling of the drive shaft and the output shaft. For this purpose, the sliding sleeve can be axially displaced into at least a first and a second position by means of an actuator. This allows the drive shaft and the output shaft of a drive train to be directly or indirectly coupled to one another and torque to be reliably transmitted via the sliding sleeve. The torque transmission can be achieved in particular by a positive-locking connection of the sliding sleeve with a connecting component of the drive shaft and a connecting component of the output shaft. The connecting components can in particular be gears that can be brought into positive engagement with the sliding sleeve in the axial direction.The input shaft and output shaft can be operatively connected to the sliding sleeve either directly or indirectly. Whether the input shaft and output shaft are coupled or decoupled can be determined by the axial position of the sliding sleeve. The driver coupled to the sliding sleeve and the sensor unit allow the axial displacement of the driver to be precisely determined and the position of the sliding sleeve to be determined. The driver and sensor unit thus enable a cost-effective, space-saving, and reliable coupling device.

[0011] Advantageous aspects are explained below, and preferred modified embodiments are described further below. Explanations, particularly regarding advantages and definitions of features, are essentially descriptive and preferred, but not limiting, examples. If an explanation is limiting, this will be expressly stated.

[0012] It is particularly preferred that the sliding sleeve is rotatably mounted by means of a bearing, wherein the sliding sleeve in particular has an internal toothing arranged on an inner circumference, which can be brought into engagement with an external toothing arranged on an outer circumference of the drive shaft and simultaneously with an external toothing arranged on an outer circumference of the output shaft for coupling the drive shaft to the output shaft. The sliding sleeve is in particular annular in design, with the internal toothing provided on its radial inner circumference. By displacing the sliding sleeve along its axial direction, which coincides with the respective axial directions of the drive shaft and output shaft, a positive connection is established between the internal toothing of the sliding sleeve and the external toothings of the drive shaft and output shaft.Due to the positive engagement between the internal gearing of the sliding sleeve and the external gearing of the input and output shafts, the sliding sleeve rotates together with the input and output shafts. Therefore, the sliding sleeve must be rotatably mounted by means of the bearing relative to the stationary components of the clutch device, in particular relative to the housing, the driver, and / or the actuator. The bearing can be designed, in particular, as an axial needle bearing.

[0013] In a preferred embodiment of the above, the sensor unit is designed as a displacement sensor. Consequently, any sensors capable of performing displacement measurement can be used. In particular, the sensor unit is designed as a Hall sensor. Magnetic fields can be detected using a Hall sensor. The Hall sensor typically consists of a semiconductor material through which an electric current flows. When the Hall sensor is exposed to a magnetic field, the current flowing through it undergoes a deflection due to the Hall effect. This deflection generates a voltage referred to as the Hall voltage. The Hall voltage is directly proportional to the strength of the magnetic field and can therefore be used to measure the magnetic field strength.By using Hall sensors, a cost-effective and space-saving position determination of the sliding sleeve in the coupling device can be realized.

[0014] In a preferred embodiment of the above, it is provided that the driver has at least one magnetic element. A magnetic field can be emitted by the driver through the at least one magnetic element. The magnetic field can be measured by the sensor unit and the displacement of the driver can be determined thereby. In particular, it is provided that the driver has a recess for at least positively receiving the at least one magnetic element. By receiving the magnetic element within a recess, the operational reliability of the coupling device can be further increased by preventing unintentional detachment of the magnet from the driver. It is preferably provided that the sensor unit detects the magnetic field generated by the at least one magnetic element.

[0015] In one embodiment of the invention described above, the actuator has at least one recess extending in the axial direction for receiving and guiding the driver in the axial direction. In particular, the driver is arranged at least partially between two actuating elements of the actuator along the circumferential direction of the sliding sleeve, wherein the actuating elements of the actuator are arranged in a form-fitting manner on the sliding sleeve. The actuator can in particular be an electromechanical component such as an electric motor or pneumatic actuating element. The actuator can in particular be designed as a shift crown or shift finger. The displacement generated by the actuator can be transmitted to the sliding sleeve and to a component connected to the sliding sleeve, in particular the driver. The driver can be arranged in the circumferential direction between two actuating elements of the actuator.This allows additional installation space to be saved, especially in the radial direction.

[0016] In a preferred embodiment of the above, the sliding sleeve is ring-shaped and is positively connected to the driver. In particular, the sliding sleeve has internal and / or external teeth extending along the circumferential direction. Preferably, the driver is arranged in a positively locking manner on an outer circumferential surface of the sliding sleeve on a groove and / or a projection. In particular, the driver is arranged in a positively locking manner on an inner circumferential surface of the sliding sleeve on a groove and / or a projection. Due to the positive connection between the sliding sleeve and the driver, the sliding sleeve can also be rotatably mounted.The relative play between the sliding sleeve and the driver in the axial direction is very small, which means that a precise determination of the axial position of the sliding sleeve can be derived from the axial displacement of the driver.

[0017] In a preferred embodiment of the above, it is provided that the sensor unit is fixedly arranged on a housing wall of the coupling device. In particular, it is provided that the sensor unit extends at least partially in the axial direction from the housing wall in the direction of the sliding sleeve and / or driver. It is preferably provided that the sensor unit is arranged upstream or downstream of the driver in the radial direction from the inside to the outside. In particular, it is provided that the sensor unit and the driver are arranged at least partially in the same axial region. Such an arrangement allows the sensor unit and the driver to overlap in the radial direction. Advantageously, the sensor unit can be easily replaced or serviced from the outside via the housing wall. This can further reduce costs.

[0018] In a preferred embodiment of the above, the driver is mounted, at least in sections, on one or more of the housing walls of the coupling device, so that it can be displaced in the axial direction. Mounting the driver on the housing wall prevents the driver from tilting or becoming dislodged during operation. In addition, small forces in the circumferential direction, caused by friction effects at the contact points with the sliding sleeve, can be reliably compensated via the housing wall.

[0019] In a preferred embodiment of the above, the sliding sleeve is operatively connected only to the drive shaft in the first position, and is operatively connected to the drive shaft and the output shaft in the second position. Consequently, in the first position, the drive shaft and the output shaft are decoupled from one another. The gears of the sliding sleeve are operatively connected only to the gears of the drive shaft in the first position. Consequently, the torque transmission is interrupted in the first position. In the second position, the drive shaft and the output shaft are coupled to one another.

[0020] In the second position, the torque can be transferred from the drive shaft to the output shaft via the sliding sleeve.

[0021] In a preferred embodiment of the above-described, it is provided that the driver and / or the actuator is / are arranged in a fixed position in the circumferential direction.

[0022] The object is further achieved by a drive train for a motor vehicle, having a drive shaft, an output shaft and a coupling device according to the above-described embodiments for coupling and decoupling the drive shaft with the output shaft.

[0023] A preferred technical solution is explained in more detail below with reference to the accompanying drawings using preferred embodiments. The term "figure" is abbreviated to "Fig." in the drawings.

[0024] In the drawings Fig. 1 a partially sectioned side view of a coupling device.

[0025] The described embodiment is merely an example which can be modified and / or supplemented in many ways within the scope of the claims.

[0026] Fig.1 shows a partially sectioned side view of a coupling device 10 for coupling and decoupling a drive shaft 12 to an output shaft 14 of a motor vehicle drive train, comprising a sliding sleeve 16 mounted so as to be displaceable in the axial direction for the positive transmission of torque from the drive shaft 12 to the output shaft 14; an actuator 18 for actuating the sliding sleeve 16 in the axial direction; a driver 20 coupled to the sliding sleeve 16 and mounted so as to be displaceable in the axial direction; and a sensor unit 22 for measuring the axial displacement of the driver 20; wherein the axial position of the sliding sleeve 16 is determined by measuring the axial displacement of the driver 20. The sliding sleeve 16 is arranged on an idler gear 24, which is rotatably mounted on an intermediate shaft 28 via a needle bearing 26.The sliding sleeve 16 is located in a first axial position in which the drive shaft 12 is decoupled from the output shaft 14. The sliding sleeve 16 toothing 40 of the output shaft 14 is not radially overlapped by the sliding sleeve 16. The sliding sleeve 16 has a projection 28 extending along its outer circumference. The driver 20 and the actuating element 30 of the actuator 18 each have grooves 32 for positive engagement with the projection 28, with both the driver 20 and the actuator 18 being arranged stationary in the circumferential direction within the coupling device 10. By the actuator 18 acting on the sliding sleeve 16 in the axial direction, the driver 20 is also moved indirectly in the axial direction via the sliding sleeve 16.By means of two magnetic elements 34, each of which is positively embedded in a recess 36 in the driver, the sensor unit 22 can measure the displacement of the driver 20 and thus indirectly determine the axial position of the sliding sleeve 16. The sensor unit 22 is also arranged in a fixed position on a housing wall 38. List of reference symbols 10 Coupling device 12 Drive shaft 14 Output shaft 16 sliding sleeve 18 Actuator 20 carriers 22 Sensor unit 24 idler gear 26 needle bearings 28 lead 30 Actuating element 32 grooves 34 Magnetic element 36 recess 38 Housing wall 40 gearing

Claims

[1] Coupling device for coupling and decoupling a drive shaft (12) to an output shaft (14) of a drive train of a motor vehicle, with a sliding sleeve (16) mounted so as to be displaceable in the axial direction for the positive transmission of a torque from the drive shaft (12) to the output shaft (14); an actuator (18) for actuating the sliding sleeve (16) in the axial direction into at least a first position and a second position; a driver (20) coupled to the sliding sleeve (16) and mounted so as to be displaceable in the axial direction; a sensor unit (22) for measuring the axial displacement of the driver (20); wherein the axial position of the sliding sleeve (16) can be determined by measuring the axial displacement of the driver (20), characterized bythat the actuator (18) has at least one recess extending in the axial direction for receiving and guiding the driver (20) in the axial direction, , wherein the actuating elements (30) of the actuator (18) are arranged in a form-fitting manner on the sliding sleeve (16). [2] Coupling device according to claim 1, wherein the sensor unit (22) is designed as a displacement sensor. [3] Coupling device according to claim 1 or 2, wherein the driver (20) has at least one magnetic element (34), wherein in particular the driver (20) has a recess (36) for at least positively receiving the at least one magnetic element (34), wherein in particular the sensor unit (22) detects the magnetic field generated by the at least one magnetic element (34). [4] Coupling device according to one of the preceding claims, wherein the driver (20) is arranged along the circumferential direction of the sliding sleeve (16) at least partially between two actuating elements (30) of the actuator (18). [5] Coupling device according to one of the preceding claims, wherein the sliding sleeve (16) is annular and is positively connected to the driver (20). [6] Coupling device according to one of the preceding claims, wherein the sensor unit (22) is arranged in a fixed position on a housing wall (38) of the coupling device (10). [7] Coupling device according to one of the preceding claims, wherein the driver (20) is mounted at least in sections on a / the housing wall (38) of the coupling device (10) so as to be displaceable in the axial direction. [8] Coupling device according to one of the preceding claims, wherein the sliding sleeve (16) in the first position is only operatively connected to the drive shaft (12), and wherein the sliding sleeve (16) is operatively connected to the drive shaft (12) and the output shaft (14) in the second position. [9] Coupling device according to one of the preceding claims, wherein the driver (20) and / or the actuator (18) is / are arranged stationary in the circumferential direction. [10] Drive train for a motor vehicle, comprising a drive shaft (12), an output shaft (14) and a coupling device (10) according to one of the preceding claims for coupling and decoupling the drive shaft (12) with the output shaft (14).

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