Electric machine output shaft

Abstract

The present invention relates to a linkage system for an output shaft (21) of an electric machine with a transmission system, the linkage system being formed by a linkage element (3) mounted on the output shaft (21), the output shaft (21) having knurling (22). Abstract figure: Figure 1

Description

Title of the invention: Electric machine output shaft

[0001] The present invention relates to the field of mobility equipment, in particular motor vehicles, and more specifically to an output shaft of an electric machine for an electric propulsion system enabling the transmission of power to drive the wheels of such equipment.

[0002] The electric propulsion system enabling the transmission of power in a motor vehicle aims to drive at least one wheel of the vehicle in rotation, by transmitting the torque supplied by a drive shaft, in particular electric or hybrid.

[0003] Such a system comprises an electrical machine consisting of at least one electric motor, an electronic assembly, and a reducer for transmitting torque.

[0004] The motor output shaft is used for the transmission link, for example by belt.

[0005] The belt is thus configured to transmit engine torque to at least one drive wheel of the vehicle, in particular to two drive wheels of the vehicle. A drawback in these systems today stems from the fact that the output shaft interface is not adaptable to all types of belts or other transmission elements.

[0006] The present invention therefore aims to overcome one or more of the drawbacks of prior art systems by proposing a linking element for output shaft allowing the shaft to be adapted to any type of transmission element.

[0007] For this purpose, the present invention proposes a linkage system, for an output shaft of an electric machine, with a transmission system, the linkage system being formed by a linkage element mounted on an output shaft, the output shaft having a knurling.

[0008] According to one embodiment of the invention, the connecting element is formed by a ring having grooves or teeth.

[0009] According to one embodiment of the invention, the ring (31) has an internal face (33) with a hardness lower than that of the grooves (32) or teeth (32).

[0010] According to one embodiment of the invention, the connecting element (3) is held in place on the shaft (21) by a retaining element (34).

[0011] According to one embodiment of the invention, the inner face (33) is treated thermochemically or by quenching.

[0012] According to one embodiment of the invention, the thermochemical treatment is carburizing, carbonitriding or nitriding.

[0013] According to one embodiment of the invention, the hardening is carried out after surface heating by induction, flame, laser, electron bombardment.

[0014] The invention also relates to an electric machine for a mobility device comprising a linking system (10) according to the invention.

[0015] The invention also relates to the use of the electric machine according to the invention in a propulsion system for a mobility device.

[0016] The invention also relates to a mobility device, comprising a coupling system according to the invention.

[0017] Other objects, features and advantages of the invention will be better understood and will become more apparent upon reading the description given below, with reference to the accompanying figures, given by way of example and in which:

[0018] [Fig-1]: [Fig.1] is an elevation view of part of a tree with a system of connection according to an embodiment of the invention,

[0019] [Fig.2]: [Fig.2] is an elevation view of a part of the linking system according to an embodiment of the invention,

[0020] [Fig. 3]: [Fig. 3] is an elevational view of part of a tree with part of the connection system according to an embodiment of the invention.

[0021] The invention relates to a linkage system for an output shaft of an electric machine. The electric machine is a machine in a propulsion system for a mobility device. The present invention is particularly intended for use in a motor vehicle, but also for use in any land, air, or sea vehicle intended for the transport of passengers or goods, whether light, medium, or heavy, as well as construction or agricultural machinery.

[0022] In the context of the invention, a propulsion system is a system which enables propulsion and includes the elements which enable the transmission of power from the engine to the wheel.

[0023] The electric machine includes at least one electric motor, an electronic assembly, and a reducer for transmitting torque.

[0024] According to one embodiment of the invention visible [Fig.1], the motor 2 is an electric motor.

[0025] The electric motor 2, via the gearbox, thus drives at least one rotating wheel. The gearbox allows a reduction ratio to be applied to the motor: it reduces the motor's output speed while increasing the torque to adapt to the operating requirements.

[0026] According to one embodiment of the invention, the coupling, via the motor shaft, between the motor 2 and the reducer is achieved with a belt.

[0027] In the context of the invention, the connection between the output shaft of the electric motor 2 and the belt is achieved by a linkage system 10.

[0028] According to one embodiment of the invention, the linking system 10 is formed by a linking element 3, visible [Fig. 2], mounted on a shaft 21 having a knurling 22, visible [Fig.3]. The connecting element 3 is formed by a ring 31 having splines 32 or teeth 32. These splines or teeth 32 allow the torque to be transmitted via a belt.

[0029] According to one embodiment of the invention, the connecting element is held in place on the shaft 21 by a retaining element of the nut type 34.

[0030] In the context of the invention, the inner face 33 of the ring 31, i.e., the interface area with the shaft 21, has a lower hardness than the splines 32 or teeth so that the material can deform for a better interface. Whereas the splines 32 or teeth must be able to withstand the contact pressures with another gear. For example, the interface area with the shaft has a hardness of 18 HRC and the splines 32 or teeth have a hardness of 59 HRC.

[0031] According to one embodiment of the invention, the interface zone 33 is treated thermochemically or by quenching, that is to say by a surface hardening treatment aimed at hardening the surface of the material.

[0032] According to one embodiment of the invention, the thermochemical treatment which allows the chemical composition of the surface to be modified is, for example, carburizing, carbonitriding, nitriding.

[0033] According to one embodiment of the invention, the hardening is carried out after surface heating by induction, flame, laser, electron bombardment.

[0034] Such a system allows, with the same drive shaft, the adaptation of different types of transmission means, such as different belts, only by changing the connecting part 3.

[0035] An electric machine incorporating such a linkage system can be used in a 2, 3, 4 or more wheeled mobility device. For example, a motor vehicle or a motorcycle, in propulsion, alternator-starter or hybrid mode.

[0036] The scope of the present invention is not limited to the details given above and allows for embodiments in many other specific forms without departing from the field of application of the invention. Therefore, the present embodiments should be considered by way of illustration and may be modified without, however, departing from the scope defined by the claims.

Claims

Demands

1. Linking system (10), for an output shaft (21) of an electric machine, with a transmission system, the linking system being formed by a linking element (3), formed by a ring (31) having splines (32) or teeth (32), mounted on an output shaft (21), the output shaft (21) having a knurling (22), the ring (31) having an internal face (33) with a hardness lower than that of the splines (32) or teeth (32).

2. Linking system (10) according to claim 1, wherein the linking element (3) is held in place on the shaft (21) by a retaining element (34).

3. A bonding system (10) according to any one of claims 1 or 2, wherein the inner face (33) is thermochemically treated or quenched.

4. Bonding system (10) according to claim 3, wherein the thermochemical treatment is carburizing, carbonitriding or nitriding.

5. Bonding system (10) according to claim 3, wherein the hardening is carried out after surface heating by induction, flame, laser, electron bombardment.

6. Electric machine for mobility device comprising a linking system (10) according to any one of claims 1 to 5.

7. Use of the electric machine according to claim 6 in a propulsion system for a mobility device.

8. Mobility device, comprising a coupling system according to any one of claims 1 to 5.

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