Power transmission device of vehicle

Abstract

The present invention relates to a power transmission device of a vehicle, in which the central axis (C1) of a drive shaft (300) and the wheel axis (C2) of a rear wheel (200) are arranged to be vertically offset and the drive shaft (300) and the rear wheel (200) are connected via a gear box (400). Thus, a sufficient gap (G1) may be secured between a vehicle body (10) and an electric axle (100), and a loading box (20) can be downwardly moved to the ground (30) by as much as the secured gap (G1) so as to enable a low floor configuration of the loading box (20).

Description

vehicle powertrain

[0001] The present invention relates to a power transmission device for a vehicle, and more specifically, to a technology for a power transmission device for a vehicle in which the central axis of a drive shaft extended from an electric axle and the wheel axis of a rear wheel are arranged to be offset vertically, and the drive shaft and the rear wheel are connected by a gearbox.

[0002] Eco-friendly vehicles such as electric vehicles and hydrogen fuel cell vehicles are equipped with electric axles required for rear-wheel drive.

[0003] For example, among commercial vehicles equipped with electric axles, hydrogen fuel cell vehicles include a fuel cell that generates electric energy and a battery that is charged with the electric energy generated by the fuel cell.

[0004] Additionally, hydrogen fuel cell vehicles include an electric axle that powers the rear wheels via a driveshaft.

[0005] The above-mentioned electric axle includes an axle housing, a motor mounted within the axle housing and driven by electric energy from a fuel cell or battery, and the power output from the motor is transmitted to the rear wheels through a drive shaft via a reducer.

[0006] An example of a powertrain with an electric axle is a configuration in which the central axis of the drive shaft extended from the electric axle and the wheel axis of the rear wheel are aligned coaxially.

[0007] In this configuration, where the center axis of the drive shaft and the wheel axis of the rear wheel are aligned coaxially, it is difficult to secure a gap between the electric axle and the vehicle body positioned above the electric axle, and this limits the ability to lower the height of the cargo area at the rear of the vehicle.

[0008] As the height of the loading bed cannot be lowered, the driving stability of the vehicle deteriorates, and there is also a limitation that the cargo cannot be loaded high in the loading bed.

[0009] The matters described as background technology above are only intended to enhance understanding of the background of the present invention, and should not be taken as an admission that they correspond to prior art already known to those skilled in the art.

[0010] The present invention relates to a power transmission device for a vehicle in which the central axis of a drive shaft extended from an electric axle and the wheel axis of a rear wheel are arranged to be offset vertically, and the drive shaft and the rear wheel are connected to transmit power through a gearbox, and the purpose of the present invention is to secure a sufficient gap between the electric axle and a body arranged above the electric axle, thereby enabling a lowering of the loading box, thereby improving driving stability, enabling additional securing of the loading box, and optimizing the ground clearance.

[0011] In order to achieve the above-described purpose, the power transmission device of the vehicle of the present invention comprises: an electric axle arranged so as to secure a gap between the lower portion of the vehicle body and the vehicle body; and a drive shaft extending to the left and right of the electric axle and connected so as to transmit power to the rear wheels; and characterized in that the center axis of the drive shaft and the wheel axis of the rear wheels are arranged to be offset vertically.

[0012] The rear wheel axle is positioned above the center axis of the drive shaft, so that a gap is secured between the body and the electric axle by the amount of offset between the center axis and the wheel axle; and the loading box positioned on the upper part of the body is lowered by moving downward by the amount of the gap secured between the body and the electric axle.

[0013] It is characterized by further including a gearbox that connects the drive shaft and the rear wheel so that power can be transmitted while the drive shaft and the rear wheel are offset.

[0014] The above gearbox is characterized by including a first gear mechanism connected to a drive shaft; and a second gear mechanism connected to the first gear mechanism and connected to a rear wheel.

[0015] The above-mentioned electric axle includes a motor that is driven by receiving electric energy; and a reducer that connects the motor and the drive shaft; and the motor and the reducer are characterized in that the shafts that transmit power are connected in a coaxial type.

[0016] The above-mentioned electric axle includes a motor that is driven by receiving electric energy; and a reducer that connects the motor and the drive shaft; and the motor and the reducer are characterized in that the shaft that transmits power is connected in an offset type.

[0017] The motor housing enclosing the above motor, the reducer housing enclosing the reducer, and the axle tube enclosing the drive shaft are characterized in that they are configured individually or as an integral part.

[0018] When the above motor housing, reducer housing, and axle tube are configured individually, adjacent parts are characterized in that they are connected to each other through a mechanical joint structure.

[0019] It is characterized in that a suspension is installed to connect the body and the axle tube to the lower side of the axle tube that surrounds the above drive shaft.

[0020] The above suspension is characterized in that the predetermined portion is connected to the axle tube via a bracket.

[0021] The offset amount between the drive shaft and the rear wheel is characterized by being 15% to 45% of the radius of the rear wheel.

[0022] The power transmission device of a vehicle according to the present invention is configured such that the center axis of a drive shaft extending left and right from an electric axle and the wheel axle of a rear wheel are arranged to be offset vertically, and the drive shaft and the rear wheel are connected to transmit power through a gearbox, so that a sufficient gap can be secured between the vehicle body and the electric axle by considering the amount of bump by the amount by which the center axis and the wheel axle are offset, and the cargo box can be moved downward toward the ground by the amount of the secured gap, thereby enabling the cargo box to be lowered, and through this, the driving stability of the vehicle can be improved, the cargo box can be additionally secured, and the ground clearance can be optimized.

[0023] Figures 1 and 2 are a rear view and an upper view of a vehicle equipped with a power transmission device according to the present invention,

[0024] Figures 3 and 4 are plan views and rear views for explaining a structure in which a motor and a reducer of an electric axle are connected coaxially according to one embodiment of the present invention.

[0025] FIGS. 5 and 6 are plan views and rear views for explaining a structure in which a motor and a reducer of an electric axle are connected in an offset type according to another embodiment of the present invention.

[0026] In describing the embodiments disclosed in this specification, if it is determined that a detailed description of related known technology may obscure the gist of the embodiments disclosed in this specification, the detailed description thereof will be omitted. In addition, the attached drawings are only intended to facilitate easy understanding of the embodiments disclosed in this specification, and the technical ideas disclosed in this specification are not limited by the attached drawings, and it should be understood that they include all modifications, equivalents, and substitutes included in the spirit and technical scope of the present disclosure. The following disclosure is not intended to limit the present disclosure to the described form or a specific field, and it is contemplated that various alternative embodiments and modifications of the present disclosure are possible, whether explicitly described or implied herein. A person of ordinary skill in the art to which the present disclosure pertains will recognize that the form and details of the contents of the present disclosure may be changed.

[0027] The present disclosure has been described with reference to specific embodiments. However, as will be appreciated by those skilled in the art, the various embodiments disclosed herein may be modified or implemented in various other ways without departing from the spirit and scope of the present disclosure. Accordingly, the following description is to be considered illustrative and is intended to teach those skilled in the art how to make and use various embodiments. It is to be understood that the forms of the disclosure shown and described herein are to be taken as representative embodiments. Equivalent elements, materials, processes, or steps may be substituted for those exemplified and described herein. The terms "including," "comprising," "incorporating," "consisting of," "have," "is," and the like, used in describing the present disclosure, are to be construed in a non-exclusive manner, that is, to allow for the identification of items, components, or elements that are not explicitly listed. Additionally, references to the singular should be interpreted as including reference to the plural.

[0028] Furthermore, the various embodiments disclosed herein are to be taken in an illustrative and explanatory sense and should not be construed as limiting the scope of the present disclosure. Any references to joining (e.g., attached, affixed, coupled, connected, etc.) are used solely to aid understanding of the present disclosure and do not limit the location, orientation, or use of any component or method disclosed herein. Accordingly, any references to joining, if any, should be interpreted broadly. Moreover, such references to joining do not imply that two or more elements are directly connected to each other. Additionally, any numeric terms, such as "first," "second," "third," "primary," "secondary," "main," or any other generic or numerical terms, are to be taken only as identifiers to aid in understanding the various components, forms, variations, or modifications of the present disclosure, and do not imply any limitation on any component, form, variation, or modification, or any order or preference therefor. That is, while such expressions may be used to describe various components, the components are not limited by such expressions. Such expressions are used only to distinguish one component from another.

[0029] The suffixes "module" and "part" used for components in the following description are given or used interchangeably only for the convenience of writing specifications, and do not have distinct meanings or roles in themselves.

[0030] When a component is referred to as being "connected" or "connected" to another component, it should be understood that it may be directly connected or connected to that other component, but that there may be other components intervening. Conversely, when a component is referred to as being "directly connected" or "connected" to another component, it should be understood that there are no other components intervening.

[0031] Additionally, the terms “Unit” or “Control Unit” included in the name are terms widely used to name a control device (Controller) that controls a specific function of a vehicle, and do not mean a generic function unit.

[0032] The controller may include a communication device that communicates with other controllers or sensors to control the function in charge, a memory that stores operating system or logic commands and input / output information, and one or more processors that perform judgments, calculations, decisions, etc. necessary for controlling the function in charge.

[0033] Any number of components or a variety of components in any of the configurations described herein may be incorporated into the disclosure described herein. The components may include any combination of the features described herein and may be arranged in any of the various configurations described herein. The concepts relating to the structure and arrangement of the components of the present disclosure, as well as their use and operation, may be applied to any number of embodiments in any combination, as well as to the specific embodiments discussed herein. Embodiments that include those having various features in various arrangements are described below with reference to the drawings.

[0034]

[0035] Hereinafter, various embodiments disclosed in the present specification will be described in detail with reference to the attached drawings. Regardless of the drawing numbers, identical or similar components are given the same reference numbers and redundant descriptions thereof will be omitted.

[0036]

[0037] Hereinafter, a power transmission device of a vehicle according to a preferred embodiment of the present invention will be described with reference to the attached drawings.

[0038] The power transmission device of a vehicle according to the present invention includes, as illustrated in FIGS. 1 to 6, an electric axle (100) arranged so as to secure a gap (G1) between the lower portion of the vehicle body (10) and the vehicle body (10); and a drive shaft (300) extending to the left and right of the electric axle (100) and connected so as to transmit power to the rear wheels (200); and a structure in which the center axis (C1) of the drive shaft (300) and the wheel axis (C2) of the rear wheels (200) are arranged to be offset (L1) vertically.

[0039] An embodiment according to the present invention places a loading box (20) on the upper side of a body (10) at the rear of a vehicle, and places an electric axle (100) underneath the body (10).

[0040] A drive shaft (300) is connected to extend to the left and right sides of the electric axle (100), and the drive shaft (300) is connected to the rear wheel (200) so that the power of the electric axle (100) is transmitted to the rear wheel (200).

[0041] According to the present invention, the drive shaft (300) and the rear wheel (200) are arranged with an offset (L1) vertically, and more specifically, the center axis (C1) of the drive shaft (300) is positioned at the bottom and the wheel axis (C2) of the rear wheel (200) is positioned at the top to form an offset structure.

[0042] In an embodiment according to the present invention, when the wheel axle (C2) of the rear wheel (200) is positioned in an offset manner above the center axis (C1) of the drive shaft (300), a sufficient gap (G1) can be secured between the body (10) and the electric axle (100) by considering the amount of bumps equivalent to the amount by which the center axis (C1) and the wheel axle (C2) are offset.

[0043] Of course, while securing a gap (G1) between the body (10) and the electric axle (100), sufficient ground clearance (H1) can also be secured between the ground (30) and the electric axle (100).

[0044] In addition, the embodiment according to the present invention can move the loading box (20) placed on the upper part of the body (10) downward toward the ground (30) by the amount of the gap (G1) secured between the body (10) and the electric axle (100), thereby enabling the loading box (20) to be lowered, thereby improving the driving stability of the vehicle, enabling additional securing of the loading box (20), and optimizing the ground clearance (H1).

[0045] An embodiment according to the present invention further includes a gearbox (400) that connects the drive shaft (300) and the rear wheel (200) so that power transmission is possible while the drive shaft (300) and the rear wheel (200) are offset.

[0046] The gearbox (400) acts as a medium that connects the offset drive shaft (300) and the rear wheel (200) to enable power transmission.

[0047] The gearbox (400) may include a first gear mechanism (410) connected to the drive shaft (300), and a second gear mechanism (420) connected to the first gear mechanism (410) and connected to the rear wheel (200).

[0048] If the first gear mechanism (410) and the second gear mechanism (420) are not directly connected, another gear mechanism connecting the first gear mechanism (410) and the second gear mechanism (420) may be added.

[0049] An electric axle (100) according to the present invention may include a motor (110) that receives electric energy and drives; and a reducer (120) that connects the motor (110) and a drive shaft (300).

[0050] In the case of a hydrogen fuel cell vehicle, the motor (110) can be driven by being supplied with electric energy from a fuel cell or battery, the reducer (120) amplifies the torque when the motor (110) is in operation and transmits it to the drive shaft (300), and the drive shaft (300) can transmit power to the rear wheel (200) through the first and second gear mechanisms (410, 420) of the gearbox (400).

[0051] Referring to FIGS. 3 and 4, in one embodiment of the present invention, a motor (110) and a reducer (120) constituting an electric axle (100) can be connected to a shaft (130) that transmits power in a coaxial type.

[0052] When the shaft (130) transmitting the power of the motor (110) and the reducer (120) is connected in a coaxial type, the external size of the electric axle (100) can be reduced, which has the advantage of increasing the degree of freedom in installation space.

[0053] Referring to FIGS. 5 and 6, in another embodiment of the present invention, the motor (110) and the reducer (120) constituting the electric axle (100) may be connected to the shaft (140, 150) that transmits power in an offset type.

[0054]

[0055] *If the shafts (140, 150) that transmit the power of the motor (110) and the reducer (120) are connected in an offset type, there is an advantage in that the degree of design freedom can be increased in the arrangement structure of the motor (110) and the reducer (120).

[0056] In an embodiment according to the present invention, a motor housing (111) surrounding a motor (110), a reducer housing (121) surrounding a reducer (120), and an axle tube (310) surrounding a drive shaft (300) may be configured individually or integrally.

[0057] If the motor housing (111), the reducer housing (121), and the axle tube (310) are configured individually, there is an advantage in that it is easy to repair and replace in the event of a breakdown, and if they are configured as an integrated unit, there is an advantage in that it is advantageous in reducing the number of parts and reducing cost.

[0058] When the motor housing (111), the reducer housing (121), and the axle tube (310) are configured individually, adjacent parts can be connected to each other through a mechanical joint structure, and the mechanical joint structure can be any one of a bolt-fastening structure, a welding joint structure, and a press-fit joint structure, or can include one or more of them.

[0059] In an embodiment according to the present invention, a suspension (500) may be installed to connect the body (10) and the axle tube (310) to the lower side of the axle tube (310) that surrounds the drive shaft (300).

[0060] The suspension (500) may include a leaf spring (501) and a shock absorber (502), and the leaf spring (501) may be installed to extend forward and backward, and the shock absorber (502) may be installed to extend upward and downward.

[0061] According to the present invention, a predetermined portion of the suspension (500) can be installed by being connected to an axle tube (310) via a bracket (510).

[0062] In the case of a leaf spring (501), both ends arranged front and rear may be installed by being connected to the body (10) via a bracket (520), and the middle portion may be installed by being connected to the axle tube (310) via a bracket (510).

[0063] In the case of the shock absorber (502), the lower part can be installed by being connected to the axle tube (310) via a bracket (510), and the upper part can be installed by being connected to the body (10).

[0064] In an embodiment according to the present invention, the offset (L1) amount of the drive shaft (300) and the rear wheel (200) can be installed to be offset by 15% to 45% with respect to the radius of the rear wheel (200).

[0065] If the offset (L1) amount is less than 15% of the radius of the rear wheel (200), the center axis (C1) of the drive shaft (300) and the wheel axis (C2) of the rear wheel (200) are structured to be almost coaxial, making it difficult to secure a sufficient gap (G1) between the electric axle (100) and the body (10), which makes it difficult to lower the height of the loading box (20) at the rear of the vehicle.

[0066] In addition, if the amount of offset (L1) exceeds 45% of the radius of the rear wheel (200), sufficient ground clearance (H1) cannot be secured between the ground (30) and the electric axle (100), so there is a concern that the electric axle (100) may come into contact with an obstacle on the ground (30) while driving.

[0067] Therefore, it is preferable that the offset (L1) of the drive shaft (300) and the rear wheel (200) be installed to be offset by 15% to 45% of the radius of the rear wheel (200) so as to secure a sufficient gap (G1) between the electric axle (100) and the body (10) and also to secure a sufficient ground clearance (H1).

[0068] As described above, the power transmission device of the vehicle according to the present invention is configured such that the central axis (C1) of the drive shaft (300) extending left and right from the electric axle (100) and the wheel axis (C2) of the rear wheel (200) are arranged to be offset vertically, and the drive shaft (300) and the rear wheel (200) are connected to transmit power through a gearbox (400), so that a sufficient gap (G1) can be secured between the body (10) and the electric axle (100) by considering the amount of bump by the amount by which the central axis (C1) and the wheel axis (C2) are offset, and the loading box (20) can be moved downward toward the ground (30) by the secured gap (G1), thereby enabling the loading box (20) to be lowered, and through this, there are advantages in that the driving stability of the vehicle can be improved, the loading box (20) can be additionally secured, and the ground clearance (H1) can be optimized.

[0069] Although the present invention has been illustrated and described with respect to specific embodiments, it will be apparent to those skilled in the art that the present invention may be variously improved and modified without departing from the technical spirit of the invention as defined by the following claims.

[0070] [Explanation of symbols]

[0071] 10 - Body

[0072] 20 - Loading bay

[0073] 30 - Ground

[0074] 100 - Electric axle

[0075] 110 - Motor

[0076] 111 - Motor Housing

[0077] 120 - Reducer

[0078] 121 - Reducer Housing

[0079] 130,140,150 - Shaft that transmits power to the motor and reducer

[0080] 200 - Rear wheel

[0081] 300 - Driveshaft

[0082] 310 - Axle Tube

[0083] 400 - Gearbox

[0084] 410 - First gear mechanism

[0085] 420 - Second gear mechanism

[0086] 500 - Suspension

[0087] 501 - Leaf Spring

[0088] 502 - Shock Absorber

[0089] 510,520 - Bracket

[0090] C1 - Center axis of drive shaft

[0091] C2 - Rear wheel axle

[0092] G1 - Gap between body and electric axle

[0093] H1 - Ground clearance

[0094] L1 - Offset

Claims

1. An electric axle positioned so as to secure a gap between the lower part of the vehicle body and the vehicle body; and It includes a drive shaft that extends to the left and right of the above-mentioned electric axle and is connected so as to transmit power to the rear wheels; A power transmission device for a vehicle, characterized in that the center axis of the drive shaft and the wheel axle of the rear wheel are arranged to be offset vertically.

2. In claim 1, The rear wheel axle is positioned above the center axis of the drive shaft, so that a gap is secured between the body and the electric axle equal to the offset amount of the center axis and the wheel axle; A power transmission device for a vehicle characterized in that the loading box positioned on the upper part of the body can be lowered by moving downward by the amount of gap secured between the body and the electric axle.

3. In claim 1, A power transmission device for a vehicle, characterized in that it further includes a gearbox that connects the drive shaft and the rear wheel so that power can be transmitted while the drive shaft and the rear wheel are offset.

4. In claim 3, The above gearbox comprises a first gear mechanism connected to a drive shaft; and A power transmission device for a vehicle, characterized by including a second gear mechanism connected to the rear wheel while being connected to the first gear mechanism.

5. In claim 1, The above electric axle is a motor that is driven by receiving electric energy; and It comprises a reducer connecting the above motor and the drive shaft; A power transmission device for a vehicle, characterized in that the above motor and reducer are connected in a coaxial type with a shaft that transmits power.

6. In claim 1, The above electric axle is a motor that is driven by receiving electric energy; and It comprises a reducer connecting the above motor and the drive shaft; A power transmission device for a vehicle, characterized in that the above motor and reducer have shafts that transmit power connected in an offset type.

7. In claim 5, A power transmission device for a vehicle, characterized in that the motor housing enclosing the motor, the reducer housing enclosing the reducer, and the axle tube enclosing the drive shaft are configured individually or as an integral part.

8. In claim 7, A power transmission device for a vehicle, characterized in that when the above motor housing, reduction gear housing, and axle tube are configured individually, adjacent parts are connected to each other through a mechanical joint structure.

9. In claim 1, A power transmission device for a vehicle, characterized in that a suspension is installed to connect the body and the axle tube to the lower side of the axle tube that surrounds the drive shaft.

10. In claim 9, A power transmission device of a vehicle, characterized in that a predetermined portion of the above suspension is connected to an axle tube via a bracket.

11. In claim 1, A power transmission device of a vehicle, characterized in that the offset amount between the drive shaft and the rear wheel is 15% to 45% of the radius of the rear wheel.

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