Patent Application
20240416746
This application claims priority to European Patent Application No. 23179029.6, filed on Jun. 13, 2023, the disclosure and content of which is incorporated by reference herein in its entirety.
The disclosure relates generally to the field of vehicles. In particular aspects, the disclosure relates to a gearbox assembly and to a powertrain assembly for a vehicle axle, and to a related vehicle.
The present disclosure is particularly suitable for electrically driven vehicle axles or E-axles, and can be applied to heavy-duty or medium-duty vehicles, e.g., trucks, and will be described herein by making more specific reference to such applications, without intending in any way to restrict its possible applications.
As known, E-axles are used to drive the wheels of a vehicle, such as of trucks used for example for heavy-duty or medium-duty applications.
Modern E-axles can be functionally quite effective. However, they are challenging to package within the available space of the vehicle to allow routing of many components needed to support the truck propulsion, such as for instance high voltage cables, brake lines, pneumatics, cooling hoses, harnesses, etc., and actually there is need, desire and room for further improvements in the way they are realized.
According to a first aspect of the disclosure, there is provided a gearbox assembly for a vehicle axle which extends along a rotation axis, the assembly comprising at least:
In some examples, the plurality of countershaft assemblies comprises:
In some examples, said first and second countershafts are positioned around the rotation axis along a virtual circumference having, as its center, the rotation axis, with their respective first and second rotation axes that are located diametrically opposite to each other with respect to the rotation axis itself.
In some examples, the plurality of countershaft assemblies comprises:
In some examples, said first, second and third countershafts are positioned around the rotation axis with their respective rotation axes positioned at the vertices of a substantially equilateral triangle.
In some examples, the clutch is positioned between the planet carrier and the differential and is configured to be operated to shift, along the rotation axis, between said first and second positions.
In some examples, the clutch comprises or is constituted by a dog clutch.
In some examples, the free wheeling gear comprises one or more teeth configured to engage with the clutch in said first position and to be disengaged from the clutch in said second position.
In some examples, the gearbox assembly further comprises a coupling gear which is mounted along the vehicle axle concentrically to the rotation axis and is adapted to be operatively connected to said motor.
In some examples, the coupling gear is mechanically connected to the sun gear via a coupling member.
According to a second aspect of the disclosure, there is provided a powertrain assembly for rotating a vehicle axle around a rotation axis, the powertrain assembly comprising
In some examples, the motor is an electric motor having a stator and a rotor, wherein the motor is mounted with its rotor rotating about an axis substantially parallel to the rotation axis of the vehicle axle.
In some examples, the powertrain assembly further comprises a gear set configured for mechanically coupling an output shaft of the motor with the gearbox assembly.
In some examples, the gear set comprises a first gear suitable to be mounted on the output shaft of the motor and a second gear suitable to be positioned between and to engage with both said first gear and said coupling gear of the gearbox assembly.
In some examples, the gear set comprises only a first gear suitable to be mounted on the output shaft of the motor and to engage with said coupling gear of the gearbox assembly.
In some examples, said motor is an electric motor having a stator and a rotor, wherein the motor is mounted along the vehicle axle with its rotor rotating positioned concentrically to the rotation axis.
In some examples, the rotor of said motor is coupled directly with the sun gear.
According to a further aspect of the disclosure, there is provided a vehicle comprising at least a gearbox assembly or a powertrain assembly as defined above, and in particular as hereinafter described and claimed in the accompanying claims.
In some examples, the vehicle is a heavy-duty or medium-duty vehicle.
In some examples, the vehicle is a heavy-duty or medium-duty truck.
Thanks to one or more of the above aspects, a technical benefit may include the possibility of obtaining a flexible and scalable configuration, according to a design that can be properly selected depending on the specific applications, and that in any case is extremely robust, compact and allows for maximum modularity of applications, such as for heavy duty/medium duty applications.
Another technical benefit may include obtaining a very simple bearing layouts, eliminating or at least reducing the need for bearings supporting the planet carrier, thus leading to simplification and improved float/load share.
Another technical benefit may include obtaining a simplification of the differential bearings due to the radial force elimination that occurs with a multi-countershaft design. This leads to use of simple bearings not requiring shimming or adjustment.
Another technical benefit may include the possibility of obtaining multiple speed ratios in an effective and efficient way.
Another technical benefit may include using simple and already clutch system, with full floating of critical components for example of the planetary system.
Another technical benefit may include the possibility of obtaining an improved ground clearance and lightweight.
The disclosed aspects, examples (including any examples), and/or accompanying claims may be suitably combined with each other as would be apparent to anyone of ordinary skill in the art. Additional features and advantages are disclosed in the following description, claims, and drawings, and in part will be readily apparent therefrom to those skilled in the art or recognized by practicing the disclosure as described herein.
Examples are described in more detail below with reference to the appended drawings.
The detailed description set forth below provides information and examples of the disclosed technology with sufficient detail to enable those skilled in the art to practice the disclosure.
In general, vehicle axles, and in particular electric or E-axle of vehicles, may be somehow difficult and cumbersome to be installed and their structure and configuration may not be flexible enough to be applied to different vehicles.
To this regard, and as it will become more evident hereinafter, the present disclosure provides a gearbox assembly for a vehicle axle, as well as a powertrain assembly comprising such gearbox assembly, comprising: a planetary gear system suitable to receive power from a motor, in particular an electric motor, associated to and configured for driving the wheels attached at the ends of the vehicle axle, a differential positioned adjacent to the planet carrier of the planetary gear system; a free wheeling gear located concentrically to an output shaft of the planet carrier; a plurality of countershaft assemblies configured for coupling with the free wheeling gear and an output gear of the differential; and a clutch which is configured to be shifted between a first position where it couples the planet carrier with the free wheeling gear, and a second position where it couples the planet carrier with the differential.
The gearbox assembly and the powertrain assembly according to the disclosure may thus result in obtaining a multi-speed output of the differential, may have a robust and compact structure, and may also have a simplified and modular configuration that may be applied to different vehicles.
The gearbox assembly 1 is suitable to be installed along a vehicle axle, in particular an E-axle, an example of which is shown in
The vehicle axle 100 extends along a longitudinal axis, indicated in the figures by the capital letter X, around which the wheels (not illustrated) attached to the opposite ends 101 and 102 (see
The gearbox assembly 1 is shown in the figures coupled to a motor 200 which is suitable to provide the gearbox assembly 1 with the power/torque needed for rotating the wheels.
In particular, the gearbox assembly 1 comprises at least:
The planetary gear system 10 comprises for example a ring gear 12 which is suitable to be connected to a housing, e.g. a housing of the assembly illustrated in
The differential 30 is positioned along the rotation axis X and comprises a shaft member 31 which is positioned along the axle 100, rotating around the rotation axis X, and has a first end which is adjacent to and faces the output member 20 of the planet carrier 18, and an output gear 32 which is positioned, on the shaft member 31, concentrically to the rotation axis X, for instance at a second end of the shaft member 31 opposite to said first end.
In one possible example, the free wheeling gear 40 is located around and concentrically to the output member 20 of the planet carrier 18.
Each of the plurality of countershafts assemblies comprises a respective countershaft which is positioned rotating about an axis substantially parallel to the rotation axis X, and two respective countershaft gears which are mounted on the corresponding countershaft, spaced apart from each other, and are configured to engage one with the free wheeling gear 40 and the other with the output gear 32 of the differential 30, respectively.
The clutch 80 is shown in
In one possible example, the clutch 80 is positioned, along the axis X, between the planet carrier 18, and in particular its output member 20, and the differential 30, in particular the first end portion of the shaft member 31, and is configured to be operated to shift, along the rotation axis X, between said first and second positions.
In this way, when the clutch 80 is operated, for instance shifting in a first direction (see arrow A in
When the clutch 80 is shifted along the axis 100 in the other direction (see arrow B in
Thus, different speeds, to be transmitted to the wheels, can be usefully obtained at the output of the differential 30.
In one possible example, the clutch 80 comprises or is constituted by a dog clutch.
In one possible example, the free wheeling gear 40 comprises one or more teeth configured to engage with the clutch 80 in said first position and to be disengaged from the clutch 80 in said second position.
In one possible example, as illustrated in
In particular, according to one aspect, the first countershaft 52 is positioned on one side of the rotation axis 100 rotating about the first axis X1 parallel to the rotation axis X, and the second countershaft 62 is positioned, with respect to the rotation axis X, on a side of the opposite to the one side where the first countershaft 52 is positioned, and rotates about the second axis X2.
In practice, the first countershaft 52 and the second countershaft 62 are positioned (seen in a transversal view perpendicular to the rotation axis X) along a virtual circumference having, as its center, the rotation axis X, and where the respective axes X2 and X3 are located diametrically opposite to each other with respect to the rotation axis X, i.e., they are located at the ends of a diameter of such virtual circumference.
In another possible example, as illustrated in
According to this example, in one possible aspect the first, second and third countershafts 52, 62, 72 are positioned around the vehicle axle 100 with their respective rotation axes X1, X2, X3 which are positioned, seen in a transversal plan substantially perpendicular to the rotation axis X, at the vertices of a substantially equilateral triangle, represented in
In one possible example, the gearbox assembly 1 further comprises a coupling gear, indicated in the figures by the reference number 3, which is mounted along the vehicle axle 100 concentrically to the rotation axis X, and is adapted to be operatively coupled to a motor, such as the motor 200, providing motion/torque to the gearbox assembly 1.
In one possible example, the coupling gear 3 is connected mechanically to the sun gear 14 via a coupling member 5, such as a spline or any suitable mechanical coupling member.
In practice, the whole gearbox assembly 1 forms a kind of compact module which can be coupled to any desired motor 200 according to the specific applications and needs, thereby forming a powertrain assembly for the vehicle axle 100, as for example illustrated in
To this end, the motor 200, to be associated to the gearbox assembly 1, can be mounted inside a housing, which can be the same housing 2 accommodating the gearbox assembly 1 and suitably shaped to house also the motor 200, or inside an additional housing coupled to the housing 2.
As those skilled in the art would easily appreciate, any housing used for accommodating the components of the gearbox assembly 1 alone, or the whole power train assembly can be realized in any suitable number of pieces.
In a possible example, the motor 200 is an electric motor having a stator and a rotor, according to solutions well known or readily available to those skilled in the art and therefore herein not described in details.
In particular, in a possible example, as illustrated for instance in the attached figures, the motor 200 is mounted with its rotor rotating about an axis X4 substantially parallel to the longitudinal axis X of the vehicle axle 100.
In one possible example, illustrated in
In one possible example, the gear set 220 comprises a first gear 222 suitable to be mounted on the output shaft 210 of the motor 200 and a second gear 224 suitable to be positioned between and to engage with both the first gear 222 and the coupling gear 3 of the gearbox assembly 1.
In this way, a first reduction, which can be suitably pre-selected, can be obtained.
In a possible example (not illustrated in the figures), the second gear 224 can be eliminated the first gear 222 and the coupling gear 3 engaging directly with each other.
In another possible example (also not illustrated in the figures) the motor 200 is an electric motor having a stator and a rotor, wherein the motor 200 is mounted along the vehicle axle 100 with its rotor rotating positioned concentrically to the rotation axis X.
In practice it has been that, according to the various examples disclosed, the presence disclosure provides a gearbox assembly 1, a powertrain assembly, and a vehicle allowing for optimized packaging, and a simplified, robust, reliable and modular structure.
In particular, the disclosure allows full floating of critical components of the planetary and central gears of the multi-countershaft section of the gearbox.
The arrangement also allows for very simple bearing layouts, eliminating the need for bearings supporting the planet carrier, thus leading to simplification and improved float/load share.
In addition to the elimination of the planet carrier support bearings, a simplification of the differential bearings occurs due to the radial force elimination that occurs with a multi-countershaft design. This leads to potentially use simple bearings not requiring shimming or adjustment.
To sum up, the following examples are given in the present disclosure.
Example 1: A gearbox assembly 1 for a vehicle axle 100 which extends along a rotation axis X, the assembly 1 comprising at least:
Example 2: The gearbox assembly 1 of example 1, wherein the plurality of countershaft assemblies comprises:
Example 3: The gearbox assembly of example 2, wherein said first and second countershafts 52, 62 are positioned around the rotation axis X along a virtual circumference having, as its center, the rotation axis X, with their respective first and second rotation axes X2, X3 that are located diametrically opposite to each other with respect to the rotation axis X itself.
Example 4: The gearbox assembly 1 of example 1, wherein the plurality of countershaft assemblies comprises:
Example 5: The gearbox assembly 1 of Example 4, wherein said first, second and third countershafts 52, 62, 72 are positioned around the rotation axis X with their respective rotation axes X1, X2, X3 positioned at the vertices of a substantially equilateral triangle.
Example 6: The gearbox assembly 1 according to any one of the previous Examples 1 to 5, wherein the clutch 80 is positioned between the planet carrier 18 and the differential 30 and is configured to be operated to shift, along the rotation axis X, between said first and second positions.
Example 7: The gearbox assembly 1 according to one or more of the previous Examples 1 to 6, wherein the clutch 80 comprises or is constituted by a dog clutch.
Example 8: The gearbox assembly 1 according to one or more of the previous Examples 1 to 7, wherein the free wheeling gear 40 comprises one or more teeth configured to engage with the clutch 80 in said first position and to be disengaged from the clutch 80 in said second position.
Example 9: The gearbox assembly 1 according to one or more of the previous Examples 1 to 8, wherein it further comprises a coupling gear 3 which is mounted along the vehicle axle 100 concentrically to the rotation axis X and is adapted to be operatively connected to said motor 200.
Example 10: The gearbox assembly 1 according to one or more of the previous Examples 1 to 9, wherein the coupling gear 3 is mechanically connected to the sun gear 14 via a coupling member 5.
Example 11: A powertrain assembly for a vehicle axle 100 which extends along a rotation axis X, the powertrain assembly comprising:
Example 12: The powertrain assembly according to Example 11, wherein the motor 200 is an electric motor having a stator and a rotor, wherein the motor 200 is mounted with its rotor rotating about an axis X4 substantially parallel to the rotation axis X of the vehicle axle 100.
Example 13: The powertrain assembly according to any of Examples 11 and 12, further comprising a gear set 220 configured for mechanically coupling an output shaft 210 of the motor 200 with the gearbox assembly 1.
Example 14: The powertrain assembly according to Example 13, wherein the gearbox assembly 1 is according to Example 9 or 10, and wherein the gear set 220 comprises a first gear 222 suitable to be mounted on the output shaft 210 of the motor 200 and a second gear 224 suitable to be positioned between and to engage with both said first gear 222 and said coupling gear 3 of the gearbox assembly 1.
Example 15: The powertrain assembly according to Example 13, wherein the gearbox assembly is according to Examples 9 or 10, and wherein the gear set 220 comprises only one gear 222 suitable to be mounted on the output shaft 210 of the motor 200 and to engage with said coupling gear 3 of the gearbox assembly 1.
Example 16: The powertrain assembly according to Example 11, wherein said motor 200 is an electric motor having a stator and a rotor, wherein the motor 200 is mounted along the vehicle axle 100 with its rotor rotating positioned concentrically to the rotation axis X.
Example 17: The powertrain assembly according to Example 16, wherein the rotor of the motor 200 is coupled directly with the sun gear 14.
Example 18: A vehicle comprising at least the gearbox assembly 1 according to one or more of Examples 1 to 10, or a powertrain assembly according to one or more of Examples 11 to 17.
Example 19: The powertrain assembly according to Example 18, wherein the vehicle is a heavy-duty or medium-duty truck.
The terminology used herein is for the purpose of describing particular aspects only and is not intended to be limiting of the disclosure. As used herein, the singular forms “a,” “an,” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items. It will be further understood that the terms “comprises,” “comprising,” “includes,” and/or “including” when used herein specify the presence of stated features, integers, actions, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, actions, steps, operations, elements, components, and/or groups thereof.
It will be understood that, although the terms first, second, etc., may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another. For example, a first element could be termed a second element, and, similarly, a second element could be termed a first element without departing from the scope of the present disclosure.
Relative terms such as “below” or “above” or “upper” or “lower” or “horizontal” or “vertical” may be used herein to describe a relationship of one element to another element as illustrated in the Figures. It will be understood that these terms and those discussed above are intended to encompass different orientations of the device in addition to the orientation depicted in the Figures. It will be understood that when an element is referred to as being “connected” or “coupled” to another element, it can be directly connected or coupled to the other element, or intervening elements may be present. In contrast, when an element is referred to as being “directly connected” or “directly coupled” to another element, there are no intervening elements present.
Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. It will be further understood that terms used herein should be interpreted as having a meaning consistent with their meaning in the context of this specification and the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.
In particular, when the term “adapted” or “arranged” or “configured” or “shaped”, or “set” or any equivalent or similar term is used herein while referring to any component as a whole, or to any part of a component, or to a combination of components, it has to be understood that it means and encompasses correspondingly either the structure, and/or configuration and/or form and/or positioning of the related component or part thereof, or combinations, such term refers to.
In addition, when the term “substantial” or “substantially” is used herein, it has to be understood as encompassing an actual variation of plus or minus 5% with respect to an indicated reference value, or axis, or position, and when the terms transversal or transversally are hereby used, they have to be understood as encompassing a direction non-parallel to the reference part(s) or direction(s)/axis they refer to, and perpendicularity has to be considered a specific case of transverse direction.
Further, in the foregoing description and claims, the numeral ordinals first, second, et cetera, have been used only for the sake of clarity of description and in no way they should be understood as limiting for whatsoever reason, nor that the order should be necessarily the one described in the illustrated exemplary example(s).
Finally, it is to be understood that the present disclosure is not limited to the aspects described above and illustrated in the drawings; rather, the skilled person will recognize that many changes and modifications may be made within the scope of the present disclosure and appended claims. In the drawings and specification, there have been disclosed aspects for purposes of illustration only and not for purposes of limitation, the scope of the disclosure being set forth in the following claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 23179029.6 | Jun 2023 | EP | regional |
