US20240017793A1

US20240017793A1 - Electric snowmobile architecture

Info

Publication number: US20240017793A1
Application number: US18/221,492
Authority: US
Inventors: Paul Dowden; Matthew Schroeder; Daniel Bell; Patrick Bernier
Original assignee: Taiga Motors Inc
Current assignee: Taiga Motors Inc
Priority date: 2022-07-18
Filing date: 2023-07-13
Publication date: 2024-01-18
Also published as: US20240017794A1; CA3207077A1; CA3207084A1

Abstract

An electric snowmobile, has: a frame extending along a longitudinal axis between a front end and a rear end, the frame including a tunnel at least partially enclosing a spacing, the tunnel having a top panel; an electric motor mounted to the frame; and a battery pack mounted to the frame and at least partially disposed rearward of the electric motor relative to the longitudinal axis, the battery pack including one or more battery modules operatively connected to the electric motor for supplying electrical energy to the electric motor, and a battery enclosure containing the one or more battery modules, the battery enclosure having a bottom panel supporting the one or more battery modules, the bottom panel of the battery enclosure secured to the top panel of the tunnel at a plurality of securing locations, the bottom panel and the top panel defining a structurally integrated double walled panel.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority from U.S. Provisional Patent Application No. 63/368,679, filed Jul. 18, 2022, and from U.S. Provisional Patent Application No. 63/370,969, filed Aug. 10, 2022, both of which are incorporated by reference in their entirety herein.

TECHNICAL FIELD

The application relates generally to snowmobiles and, more particularly, to electrically-powered snowmobiles.

BACKGROUND

Some snowmobiles combust fuel in an internal-combustion engine. The architecture of such fuel-consuming snowmobiles is designed to accommodate the size, weight and loads generated by the internal-combustion engine during operation of the snowmobile. The architecture of such fuel-consuming snowmobiles is also designed to accommodate the evacuation of hot combustion gases, cooling of components, and the lubrication of still other components.
For snowmobiles having batteries which supply electrical power to one or more electric motors for propulsion, the architecture of the snowmobile may be different than that of fuel-consuming snowmobiles.

SUMMARY

In one aspect, there is provided an electric snowmobile, comprising: a frame extending along a longitudinal axis between a front end and a rear end of the frame, the frame including a tunnel at least partially enclosing a spacing receiving a drive track, the tunnel having a top panel; an electric motor mounted to the frame; and a battery pack mounted to the frame and at least partially disposed rearward of the electric motor relative to the longitudinal axis, the battery pack including one or more battery modules operatively connected to the electric motor for supplying electrical energy to the electric motor, and a battery enclosure containing the one or more battery modules, the battery enclosure having a bottom panel supporting the one or more battery modules, the bottom panel of the battery enclosure secured to the top panel of the tunnel at a plurality of securing locations, the bottom panel and the top panel defining a structurally integrated double walled panel.
The electric snowmobile described above may include any of the following features, in any combinations.
In some embodiments, an effective thickness of the top panel of the tunnel corresponds to a thickness of the top panel plus a thickness of the bottom panel.
In some embodiments, a ratio of a thickness of the top panel of the tunnel to a thickness of the bottom panel of the battery enclosure ranges from 1.0 to 1.5.
In some embodiments, a distance between the bottom panel of the battery enclosure and the top panel of the tunnel ranges from about 1.5 mm to 2 mm.
In some embodiments, the bottom panel of the battery enclosure and the tunnel are made of two different materials.
In some embodiments, the bottom panel is made of aluminum, and the tunnel is made of aluminum.
In some embodiments, the bottom panel is free of contact with the tunnel.
In some embodiments, a damping layer is disposed between the top panel of the tunnel and the bottom panel of the battery enclosure.
In some embodiments, the top panel of the tunnel is parallel to the bottom panel of the battery enclosure.
In some embodiments, the plurality of securing locations are disposed along a perimeter of the bottom panel.
In some embodiments, the plurality of securing locations are distributed in two rows each extending longitudinally relative to the longitudinal axis and disposed adjacent a respective one of two side longitudinal edges of the bottom panel.
In some embodiments, the battery enclosure includes a cover removably securable to the bottom panel.
In some embodiments, the bottom panel is removable from the top panel of the tunnel.
In some embodiments, bolts are at the plurality of securing locations.
In another aspect, there is provided an electric snowmobile, comprising: a frame extending along a longitudinal axis between a front end and a rear end of the frame, the frame including a tunnel at least partially enclosing a spacing receiving a drive track, and a sub-frame disposed forward of the tunnel relative to the longitudinal axis, the sub-frame supporting a front suspension; an electric motor mounted to the frame; and a structure disposed over the sub-frame, the structure including members interconnected to one another, the members made of a first material, a bracket secured to an end of a member of the members via an adhesive, the bracket secured to the tunnel, the bracket made of a second material different than the first material.
The electric snowmobile described above may include any of the following features, in any combinations.
In some embodiments, the first material is steel and the second material is aluminum.
In some embodiments, the adhesive is one or more of an epoxy and an acrylic.
In some embodiments, the structure defines two fore ends and two rear ends, the bracket including two brackets each secured to a respective one of the two rear ends, the two brackets secured to the tunnel.
In some embodiments, the structure defines two fore ends each secured to a respective one of a right suspension and a left suspension of the front suspension.
In some embodiments, the members include a left member extending upwardly from a front left end to a left apex and from the left apex downwardly to a rear left end, a right member extending upwardly from a front right end to a right apex and downwardly from the right apex to a rear right end.
In some embodiments, the right member is secured to the left member proximate the left apex and the right apex.
In some embodiments, the structure includes a bracing member connecting the left member to the right member, the bracing member secured to the left member proximate or at the left apex and secured to the right member proximate or at the right apex.
In some embodiments, the structure includes a transverse member extending substantially transversally to the longitudinal axis from a left end to a right end, the transverse member secured to the left member and to the right member.
In some embodiments, a left foot rest is secured to a left side of the tunnel and a right foot rest secured to a right side of the tunnel, the left foot rest and the right foot rest extending along the longitudinal axis from the sub-frame towards the rear end of the frame, the left end of the transverse member secured to the left foot rest proximate the sub-frame, the right end of the transverse member secured to the right foot rest proximate the sub-frame.
In some embodiments, the transverse member is secured to the left member and to the right member via left and right connecting members made of the second material, the left and right connecting members secured to the transverse member and to the left and right members via the adhesive.
In some embodiments, the left member defines a left elbow and the right member defines a right elbow, the transverse member secured to the left member proximate or at the left elbow and secured to the right member proximate or at the right elbow.
In some embodiments, a left shear plate is connecting the transverse member to the sub-frame and a right shear plate connecting the transverse member to the sub-frame.
In yet another aspect, there is provided an electric snowmobile, comprising: a frame extending along a longitudinal axis between a front end and a rear end of the frame, the frame including a tunnel at least partially enclosing a spacing receiving a drive track, a sub-frame disposed forward of the tunnel relative to the longitudinal axis, the sub-frame supporting a front suspension; an electric motor mounted to the frame; a battery pack mounted over the tunnel and at least partially disposed rearward of the electric motor relative to the longitudinal axis, the battery pack having a front portion and a rear portion, a width of the front portion relative to a transverse direction normal to the longitudinal axis being greater than a width of the rear portion; and a structure disposed over the sub-frame and over the front portion of the battery pack, the structure defining at least four legs ending at four ends, the at least four legs including two front legs secured to the front suspensions and two rear legs secured to the tunnel, each of the two rear legs defining a respective one of two elbows and a respective one of two rear ends of the four ends, the two elbows located above the two rear ends, a distance along the transverse direction between the two elbows being greater than the width of the rear portion of the battery pack to receive the rear portion between the two rear legs.
The electric snowmobile described above may include any of the following features, in any combinations.
In some embodiments, a distance along a vertical direction being normal the transverse direction between the two elbows and a top wall of the tunnel is greater than a height of the battery pack taken along the vertical direction.
In some embodiments, the two elbows are located at an intersection between the front portion and the rear portion of the battery pack.
In some embodiments, the at least four legs are defined by two members each extending upwardly from a front end to an apex and downwardly from the apex to a respective one of the two rear ends.
In some embodiments, the two members are secured to one another proximate the apexes.
In some embodiments, the structure includes a bracing member connecting the two members.
In some embodiments, the structure includes a transverse member extending substantially transversally to the longitudinal axis from a left end to a right end, the transverse member secured to the two rear legs.
In some embodiments, a left foot rest is secured to a left side of the tunnel and a right foot rest secured to a right side of the tunnel, the left foot rest and the right foot rest extending along the longitudinal axis from the sub-frame towards the rear end of the frame, the left end of the transverse member secured to the left foot rest proximate the sub-frame, the right end of the transverse member secured to the right foot rest proximate the sub-frame.
In some embodiments, the transverse member is secured to two rear legs via connecting members.
In some embodiments, a left shear plate is connecting the transverse member to the sub-frame and a right shear plate connecting the transverse member to the sub-frame.
In still another aspect, there is provided an electric snowmobile, comprising: a frame extending along a longitudinal axis between a front end and a rear end of the frame, the frame including a tunnel at least partially enclosing a spacing receiving a drive track, a sub-frame disposed forward of the tunnel relative to the longitudinal axis, the sub-frame supporting a front suspension, and a bulkhead connecting the sub-frame to the tunnel; an electric motor mounted to the frame; a battery pack mounted to the frame and at least partially disposed rearward of the electric motor relative to the longitudinal axis; and a cooling system including a liquid coolant circuit in heat exchange relationship with one or both of the electric motor and the battery pack, and a heat exchanger mounted to the bulkhead, the heat exchanger having two plates secured to the bulkhead, one of the two plates exposed to the spacing, one or more conduits defined between the two plates, the one or more conduits hydraulically connected to the liquid coolant circuit.
The electric snowmobile described above may include any of the following features, in any combinations.
In some embodiments, the two plates include a first plate secured to the bulkhead and a second plate secured to the first plate, the second plate exposed to the spacing, being embossed, and defining one or more channels, the one or more conduits extending within the one or more channels.
In some embodiments, the heat exchanger is secured to the bulkhead at a plurality of securing locations thereby increasing a stiffness of the bulkhead.
In some embodiments, the plurality of securing locations are disposed along perimeters of the two plates.
In some embodiments, the two plates are made of metal.
In some embodiments, the two plates have each a thickness of about 1.6 mm.
In another aspect, there is provided a structure for an electric snowmobile having a battery pack having a front portion and a rear portion, a width of the front portion relative to a transverse direction normal to a longitudinal axis of the electric snowmobile being greater than a width of the rear portion, the structure comprising: two front legs to secure to front suspensions of the electric snowmobile; and two rear legs to secure to a tunnel of the electric snowmobile, each of the two rear legs defining a respective one of two elbows and a respective one of two rear ends, the two elbows located above the two rear ends, a distance along the transverse direction between the two elbows being greater than a width of the rear portion of the battery pack to receive the rear portion between the two rear legs.

BRIEF DESCRIPTION OF THE DRAWINGS

Reference is now made to the accompanying figures in which:

FIG. 1 is a schematic representation of an electric snowmobile;

FIG. 2 is an enlarged three dimensional view of a transmission of the electric snowmobile of FIG. 1 ;

FIG. 3 is a three dimensional view of the electric snowmobile of FIG. 1 ;

FIG. 4 is a front three dimensional view of a frame of the electric snowmobile of FIG. 3 ;

FIG. 5 is another front three dimensional view of the frame of the electric snowmobile of FIG. 3 with a battery pack secured thereto;

FIG. 6 is a side vide of the frame and battery pack of the electric snowmobile of FIG. 3 ;

FIG. 7A is a cross-sectional view illustrating a connection arrangement between the battery pack and the frame of the electric snowmobile of FIG. 3 at first securing locations;

FIG. 7B is a cross-sectional view illustrating a connection arrangement between the battery pack and the frame of the electric snowmobile of FIG. 3 at second securing locations;

FIG. 8 is a front three dimensional view of the frame of the electric snowmobile of FIG. 3 ;

FIG. 9 is a three dimensional view of a structure to be secured to the frame of the electric snowmobile of FIG. 3 ;

FIG. 10 is a three dimensional view illustrating a connection arrangement between a member of the structure and a bracket of the structure of FIG. 9 ;

FIG. 11 is another side view of the electric snowmobile of FIG. 3 illustrating the frame and the structure;

FIG. 12 is a three dimensional view of a structure in accordance with another embodiment;

FIG. 13 is a three dimensional view of a structure in accordance with another embodiment;

FIG. 14 is a three dimensional view of a structure in accordance with another embodiment;

FIG. 15 is a bottom three dimensional view illustrating a heat exchanger secured to the frame of the electric snowmobile of FIG. 3 ;

FIG. 16 is a bottom side three dimensional view illustrating the heat exchanger and the frame;

FIG. 17 is a cross-sectional view of the heat exchanger of FIG. 15 ; and

FIG. 18 is a side view of the heat exchanger of FIG. 15 .

DETAILED DESCRIPTION

The following disclosure relates to straddle seat vehicles and associated methods for operating the straddle seat vehicles. The straddle seat vehicles are drivingly engaged to motors for effecting propulsion of the vehicles in both forward and reverse directions. In some embodiments, the straddle seat vehicles and methods described herein may be applicable to electric powersport vehicles that may be operated off-road and/or in relatively rugged environments. Examples of suitable off-road electric and non-electric powersport vehicles include snowmobiles, all-terrain vehicles (ATVs), and utility task vehicles (UTVs). As used herein, the term off-road vehicle refers to vehicles to which at least some regulations, requirements or laws applicable to on-road vehicles do not apply. In some embodiments, the vehicles and methods described herein may, based on one or more positions of an input device operatively connected to a motor, determine the forward direction and reverse direction of propulsion for the vehicle.
The terms “connected”, “connects” and “coupled to” may include both direct connection and coupling (in which two elements contact each other) and indirect connection and coupling (in which at least one additional element is located between the two elements).
With reference to FIG. 1 , an electric snowmobile in accordance with one embodiment is shown at 10. The electric snowmobile 10 may include a frame 12 (also known as a body or a chassis) which may include a tunnel 14, a drive track 15 having the form of an endless belt for engaging the ground (e.g., snow) and disposed under the tunnel 14, and a powertrain 16 mounted to the frame 12 and configured to displace the drive track 15. Skis 18 are disposed in a front portion of the electric snowmobile 10, and a straddle seat 22 is disposed above the tunnel 14 for accommodating an operator of the electric snowmobile 10 and optionally one or more passengers. Skis 18, namely left and right skis, may be movably attached to the frame 12 to permit steering of the electric snowmobile 10 via a steering assembly including a steering column 19 connected to a handle 20. Front suspensions 45 (shown in FIG. 3 ) are connected to the skis 18 and used to dampen movements of the snowmobile 10 when in use.
Referring to FIGS. 1 and 2 , the powertrain 16 of the electric snowmobile 10 includes an electric motor assembly 25. The electric motor assembly 25 is a collection of components and features which function to deliver an electric drive to displace the electric snowmobile 10. The electric motor assembly 25 includes one or more electric motor(s) 26 drivingly coupled to the drive track 15 via a drive shaft 28. In one embodiment, the electric motor 26 has a maximum output power of between 120 and 180 horse power. In other embodiments, the electric motor 26 has a maximum output power of at least 180 horse power. The drive shaft 28 may be drivingly coupled to the drive track 15 via one or more toothed wheels or other means so as to transfer motive power from the electric motor 26 to the drive track 15. The powertrain 16 may also include a battery pack 30 for providing electric energy (i.e. electric current) to the electric motor 26 and driving the electric motor 26. The operation of the electric motor 26 and the delivery of drive current to the electric motor 26 from the battery pack 30 may be controlled by a controller 32 based on an actuation of an input device 34, sometimes referred to as a “throttle” or “accelerator”, by the operator. The controller 32 and the input device 34 are part of a control system CS for controlling operation of the electric snowmobile 10. In some embodiments, the battery pack 30 may be a lithium ion or other type of battery pack 30.
In the embodiment shown, the electric snowmobile 10 has a cooling system 100 including a liquid coolant circuit 101 in heat exchange relationship with one or both of the electric motor 26 and the battery pack 30. The liquid coolant circuit 101 may extend through cooling passages defined within or around the electric motor 26 and/or within cooling passages defined within the battery pack 30. A liquid coolant may flow within the cooling passages of the liquid coolant circuit 101 to pickup heat generated by these components. This heat may then be expelled to an environment via a heat exchanger, which will be described further below.
The electric snowmobile 10 may also include one or more brake(s) 36 (referred hereinafter in the singular) that may be applied or released by an actuation of a brake actuator (e.g., lever) 38 by the operator for example. The brake 36 may be operable as a main brake for the purpose of slowing and stopping the electric snowmobile 10 during motion of the electric snowmobile 10. The brake 36 may comprise a combination of tractive braking and regenerative braking. In some embodiments, the brake 36 may be operable as described in U.S. patent application Ser. No. 17/091,712 entitled “Braking system for an off-road vehicle”, the entirety of which is incorporated herein by reference. Alternatively or in addition, the brake 36 may be operable as a parking brake, sometimes called “e-brake” or “emergency brake”, of the electric snowmobile 10 intended to be used when the electric snowmobile 10 is stationary. In various embodiments, such main and parking brake functions may use separate brakes, or may use a common brake 36. In some embodiments of tractive braking, the brake actuator 38 may be lockable when the brake 36 is applied in order to use the brake 36 as a parking brake. The brake 36 may be electrically or hydraulically operated. For example, the brake 36 may include a master cylinder operatively coupled to a brake caliper that applies brake pads against a brake rotor that is coupled to the powertrain 16. In some embodiments, such brake rotor may be secured to and rotatable with the drive shaft 28. In some embodiments of regenerative braking shown in FIG. 1 , the brake 36 is electrically connected to the battery pack 30. The brake 36 is a regenerative brake 36, or applies regenerative braking, such that the brake 36 or components thereof are able to supply the battery pack 30 with electric energy when the brake 36 is applied to a component of the powertrain 16, and/or when the operator releases the input device 34 (e.g., accelerator).
Still referring to FIGS. 1 and 2 , the electric motor 26 is in torque-transmitting engagement with the drive shaft 28 via a transmission 40. The transmission 40 may be of a belt/pulley type, a chain/sprocket type, or a shaft/gear type for example. Referring to FIG. 2 , the transmission 40 is of a belt/pulley type. The transmission 40 includes a drive belt 42 that is mounted about a motor output 26A of the electric motor 26, and is also mounted about a drive track wheel 28A for driving the drive shaft 28. The drive belt 42 therefore extends between the motor output 26A and the drive track wheel 28A for conveying torque from the electric motor 26 to the drive shaft 28. The drive shaft 28 provides torque to the drive track 15. The drive belt 42 is thus displaced or driven by the motor output 26A in a linear manner between the motor output 26A and the drive track wheel 28A, and in a circumferential manner about the motor output 26A and the drive track wheel 28A.
Referring now to FIGS. 3-4 , the electric snowmobile 10 includes front suspensions 45 connected to the skis 18. Namely, each of the front suspensions 45 is connected to a respective one of the skis 18. The frame 12 of the electric snowmobile 10 extends along a longitudinal axis L between a front end 12A and a rear end 12B. The frame 12 includes a tunnel 60 (which may be similar to tunnel 14), a sub-frame 70, and a structure 80. The sub-frame 70 is disposed forward of the tunnel 60 relative to the longitudinal axis L. The sub-frame 70 may define a cavity or spacing that is sized for receiving the electric motor 26. The electric motor 26 may be secured (e.g., fastened to the sub-frame 70). The tunnel 60 at least partially encloses a spacing receiving the drive track 15 (FIG. 1 ). The sub-frame 70 defines a bulkhead 71 that connects the sub-frame 70 to the tunnel 60. The structure 80 is disposed over the sub-frame 70. The structure 80 may be secured to the tunnel 60, to the sub-frame 70, and to the front suspensions 45. More specifically, and in the embodiment shown, the structure 80 is connected to the front suspension 45 and to the sub-frame 70 at the same one or more locations. For example, one or more brackets may each couple the structure 80 to the front suspension 45 and to the sub-frame 70. Alternatively or additionally, the structure 80, which may include transverse member 87, is connected to the front suspension 45 via left and right front legs 81A, 82A (see FIG. 8 ), and to the sub-frame 70 via transverse member 87. Thus, loads are transferred from the skis 18 to the front suspensions 45 and from the front suspensions 45 to the structure 80, and from the structure 80 to the tunnel 60 and sub-frame 70.
Referring more particularly to FIG. 4 , the tunnel 60 may be made of sheet metal having a thickness of about 1 to 3 mm, preferably about 1.6 mm. The tunnel 60 may be made of aluminum, or any other suitable material such as steel, composite (e.g., carbon fiber or fiber glass in epoxy). The tunnel 60 has a top panel 61 defining a substantially planar surface that faces upwardly in a vertical direction V. The expression “substantially” used in the context of the present disclosure is meant to encompass slight variations caused by manufacturing tolerances. The tunnel 60 includes two side panels 62 each extending downwardly from longitudinal edges 61A of the top panel 61. The two side panels 62 are therefore substantially transverse to the top panel 61 to partially enclose the spacing sized for receiving the drive track 15. The tunnel 60 may be a sheet bended to define the longitudinal edges 61A located at intersections between the top panel 61 and the two side panels 62. The tunnel 60 includes foot rests 63 (sometimes referred to as “running boards”), namely left and right foot rests each sized for receiving a foot of a user sitting on the straddle seat 22 (FIG. 1 ) of the electric snowmobile 10. The foot rests 63 may each extend transversally in a transverse direction T from a respective one of the two side panels 62. In the embodiment shown, the foot rests 63 are secured to bottom edges of the two side panels 62. The foot rests 63 extend longitudinally relative to the longitudinal axis L from the sub-frame 70 towards the rear end 12B of the frame 12.
Still referring to FIG. 4 , in the embodiment shown, a peripheral beam 64 is secured to the tunnel 60 and extends from a rear end 63A of one of the foot rests 63, wraps around a rear portion of the tunnel 60 at the rear end 12B of the frame 12 and reaches the rear end 63A of the other of the foot rests 63. The peripheral beam 64 may be secured to the tunnel 50 adjacent the rear ends 63A of the foot rests 63 and at one or more locations along its length. The peripheral beam 64 may increase a stiffness of the tunnel 60. The peripheral beam 64 may provide a bumper at the rear end 12B of the frame 12.
Referring now to FIGS. 5-6 , the battery pack 30 is mounted to the frame 12 and disposed at least partially rearward of the electric motor 26 relative to the longitudinal axis L. The battery pack 30 includes one or more battery modules 51 operatively connected to the electric motor 26 for supplying electrical energy to the electric motor 26. The battery pack 30 further includes a battery enclosure 52 containing the one or more battery modules 51. In the embodiment shown, the battery pack 30 has a front portion 30A and a rear portion 30B located rearward of the front portion 30A relative to the longitudinal axis L. A width W1 of the front portion relative to the transverse direction T normal to the longitudinal axis L is greater than a width W2 of the rear portion 30B. The width W2 of the rear portion 30B may generally correspond to the width of the straddle seat 22 disposed above the rear portion 30B, allowing an operator to straddle the rear portion 30B and access the foot rests 63. The structure 80 is designed to accommodate this battery pack 30. More details about the structure 80 are presented herein below. The rear portion 30B of the battery pack 30 is disposed above the tunnel 60. More specifically, the rear portion 30B of the battery pack 30 is secured (e.g., glued, fastened) to the top panel 61 of the tunnel 60.
The battery enclosure 52 includes a cover 53 and a bottom panel 54. The cover 53 may be removably secured to the bottom panel 54. In other words, the cover 53 may be removed from the bottom panel 54 to access the battery modules 51 and/or other components of the battery pack 30 for maintenance purposes. The battery pack 30 may be secured to the tunnel 60 via the bottom panel 54 of the battery enclosure 52. In a further embodiment, the battery pack 30 may be secured to the tunnel 60 via a combination of the bottom panel 54 and the cover 53 of the battery enclosure 52. The battery modules 51 may be supported by the bottom panel 54 and secured thereto using any suitable techniques.
One of the functions of the tunnel 60 is to support the straddle seat 22 (FIG. 1 ) and the user sitting on the straddle seat 22. Another function of the tunnel 60 is to transmit loads imparted to the electric snowmobile 10 via the drive track 15. These loads may include, for instance, acceleration and deceleration forces and moments about the longitudinal axis L. To resist the moments imparted to the tunnel 60, the tunnel 60 requires a suitable torsional stiffness. The torsional stiffness in the context of the present disclosure corresponds to the resistance of the tunnel 60 against deformation when subjected to a torque defined about the longitudinal axis L.
In the embodiment shown, the torsional stiffness of the tunnel 60 may be increased by the battery pack 30. More specifically, the bottom panel 54 of the battery enclosure 52 is secured to the top panel 61 of the tunnel 60 in a manner such that a torsional stiffness of the tunnel 60 is increased by the bottom panel 54 of the battery enclosure 52. Stated differently, the bottom panel 54 of the battery enclosure 52 is secured to the top panel 61 of the tunnel 60 at a plurality of securing locations 65 (see FIG. 4 ). Therefore, the bottom panel 54 and the top panel 61 of the tunnel 60 define a structurally integrated double walled panel.
Referring to FIGS. 4 and 7A-7B, in the embodiment shown, the securing locations 65 are distributed in two rows each extending longitudinally relative to the longitudinal axis L and disposed adjacent a respective one of the two longitudinal edges 61A of the top panel 61 of the tunnel 60. The securing locations 65 of each rows may be separated from one another by between 130-170 mm, and in some embodiments by about 150 mm. Other separations of the securing locations 65 are also contemplated. These two rows of the securing locations 65 are disposed along opposed longitudinal edges 54A of the bottom panel 54 of the battery enclosure 52. Stated differently, the top panel 61 of the tunnel 60 and the bottom panel 54 of the battery enclosure 52 are secured to one another along respective portions of their perimeters. At each of those securing locations 65, the bottom panel 54 of the battery enclosure 52 is clamped to the top panel 61 of the tunnel 60. Longitudinal edges 61A of the top panel 61 of the tunnel 60 may be substantially aligned or flush with the longitudinal edges 54A of the bottom panel 54 of the battery enclosure 52. Alternatively, the longitudinal edge 54A of the bottom panel 54 may be located laterally inwardly from the longitudinal edges 61A of the top panel 61 of the tunnel 60.
Referring to FIG. 7A, in the present embodiment, the cover 53 is secured to the bottom panel 54 at a plurality of first securing locations 49 that are spaced apart from one another by between 130-170 mm, and in some embodiments by about 150 mm. Referring to FIG. 7B, the bottom panel 54 is secured to the tunnel 60 at a plurality of second securing locations 65 that are spaced apart from one another by between 130-170 mm, and in some embodiments by about 150 mm. The first securing locations 49 of the cover 53 to the bottom panel 54 are interspaced between the second securing locations 65 of the bottom panel 54 to the tunnel 60. Hence, in an embodiment, a first securing location 49 between the cover 53 and the bottom panel 54 is spaced apart from a second securing location 65 between the bottom panel 54 and the tunnel 60 by about mm.
Referring now to FIG. 7A, a cross-sectional view illustrating a securing arrangement between the cover 53 and the bottom panel 54 at a first securing location 49 is shown. In the embodiment shown, a layer 56 of damping material, such as foam, is disposed between the top panel 61 of the tunnel 60 and the bottom panel 54 of the battery enclosure 52 to dampen vibrations. Also, a seal 55, such as a gasket made of elastomeric material, may be disposed between the bottom panel 54 of the battery enclosure 52 and a flange 53A of the cover 53 of the battery enclosure 52. This seal 55 may be used to protect the battery modules 52 contained in the battery enclosure 52 from snow, water, and other debris.
In the present embodiment, the cover 53 is secured to the bottom panel 54 at the first securing locations 49 spaced apart from one another by between 130-170 mm, and in some embodiments by about 150 mm. Threaded inserts (e.g., standoffs/clinch nuts) are secured to the bottom panel 54 at the first securing locations. Thus, threaded holes 54B may be defined by the threaded inserts. Bolts may then be inserted through registering apertures 53B, 55A defined through the flange 53A of the cover 53 and through the seal 55 until it threadingly engages the threaded holes 54B. The bolt has a head abutting the flange 53A to secure the flange 53A to the bottom panel 54. A washer may be used in some configurations.
Referring now to FIG. 7B, a cross-sectional view illustrating a securing arrangement between the bottom panel 54 and the tunnel 60 at a second securing location is shown. Registering apertures 53B, 55A, 54B, 56A, 61B may be defined through the flange 53A, the seal the bottom panel 54, the layer 56, and the top panel 61 to receive a fastener for securing the battery enclosure 52 to the top panel 61 of the tunnel 60. This fastener may include a rivet-nut secured to the top panel 61 and defining inner threads. A bolt 66 (FIG. 4 ) may be threadingly engaged to the inner threads of the rivet-nut and received through the registering apertures 53B, 54B, 56A, 61B. A nut may thus be threadingly engaged to the bolt 66 to abut against the bottom panel 54 to clamp the bottom panel 54, the layer 56, and the top panel 61 together. Washers may be used in some configurations.
As shown in FIG. 7B, a diameter of the apertures 53B, 55A defined through the flange 53A of the cover 53 and through the seal 55 may be greater than that of the apertures 54B, 56A defined through the bottom panel 54 of the battery enclosure 52 and through the layer 56. The diameter of these apertures 53B, 55A defined through the flange 53A of the cover 53 and through the seal 55 is selected to be greater than a diameter of a nut used to threadingly engage the bolt 66. Thus, at the second securing locations, only the bottom panel 54 is clamped to the top panel 61 of the tunnel 60 and no clamping force is exerted on the cover 53 at the second securing locations. This may allow for removal of the cover 53 from the bottom panel 54, without detaching the bottom panel 54 from the top panel 61 of the tunnel 60. Alternatively, the cover 53 may be clamped to the top panel 61 of the tunnel 60 at a plurality of securing locations. In other words, in an alternate embodiment, at each of the securing locations 49, 65 the flange 53A, the seal 55, the bottom panel 54, the layer 56, and the top panel 61 may be clamped together.
These fasteners at the second securing locations 65 may allow the removal of the bottom panel 54 from the top panel 61 of the tunnel 60. Stated differently, the whole battery enclosure 52 may be removable from the tunnel 60. The seal 55 and/or the layer 56 of damping material may be avoided in some embodiments.
Still referring to FIGS. 7A-7B, the top panel 61 of the tunnel 60 has a first thickness T1 and the bottom panel 54 of the battery enclosure 52 has a second thickness T2. A ratio of the first thickness T1 to the second thickness (T1/T2) may range from 1 to 1.5. In the present embodiment, an effective thickness of the top panel 61 of the tunnel 60 may correspond to the first thickness T1 of the top panel 61 plus the second thickness T2 of the bottom panel 54 of the battery enclosure 52. Herein, the expression effective thickness means that structural properties of the top panel 61 of the tunnel 60 may be increased by the bottom panel 54 of the battery enclosure 52. In other words, the torsional stiffness of the tunnel 60 may be increased by the bottom panel 54 such that the torsional stiffness of the tunnel 60 combined with the bottom panel 54 is substantially equal to what the torsional stiffness of the tunnel 60 would be if the top panel 61 had a thickness increased by the second thickness T2 of the bottom panel 54. The top panel 61 and the bottom panel 54 are substantially parallel to one another. When connected, the top panel 61 and the bottom panel 54 may compress the layer of damping material 56 such that there is no visible gap between the top panel 61 and the bottom panel 54.
Moreover, having the longitudinal edges 54A of the bottom panel 54 being substantially aligned or flush with the longitudinal edges 61A of the top panel 61 of the tunnel 60 may allow to maximize a distance D1 (FIG. 4 ) in the transverse direction T between the two rows of the securing locations 65. In turn, this may increase an effective width of a combination of the top panel 61 of the tunnel 60 and the bottom panel 54 of the battery enclosure 52. This increase in the effective width may increase the torsional stiffness of the combination of the bottom panel 54 of the battery enclosure 52 and the top panel 61 of the tunnel. Those securing locations 65 may therefore be as close as possible to the longitudinal edges 54A, 61A of the bottom panel 54 and the top panel 61. Moreover, having the top panel 61 and the bottom panel 54 close to one another may allow a reduction of the thickness of the sheet metal of the tunnel 60, which may provide significant weight savings. In one embodiment, the thickness of the top panel may be reduced by approximately 0.4 mm, which may provide about 2 kilograms of weight savings.
The bottom panel 54 and the tunnel 60 may be made of the same material, such as aluminum. Alternatively, they may be made from two different materials (e.g., steel and aluminum). In some embodiments, composite materials may be used.
In the depicted embodiment, the top panel 61 of the tunnel 60 is free of contact with the bottom panel 54 of the battery enclosure 52. A spacing or gap between the tunnel 60 and the bottom panel 54 may be sized to receive the layer 56 of damping material. A third thickness T3 of this layer 56, which substantially corresponds to a dimension of the spacing or distance between the tunnel 60 and the bottom panel 54, may be about from 1.5 mm to 2 mm. The third thickness T3 corresponds to a distance between the tunnel 60 and the bottom panel 54. The layer 56 may be compressed when the bottom panel 54 is fastened to the tunnel 60. The gap between the tunnel 60 and the bottom panel 54 may increase the effective torsional and/or bending stiffness of the tunnel 60. For example, spacing the bottom panel 54 and the top panel 61 apart from one another may improve stiffness similar to an I-beam. This may for allow a reduced thickness of the material of the tunnel 60, thereby saving weight.
In some other embodiments, the layer 56 may be removed and the top panel 61 of the tunnel 60 may be in contact against the bottom panel 54 of the battery enclosure 52. In some cases, the bottom panel 54 may be glued to the top panel 61 of the tunnel 60.
A number of the second securing locations 65 between the bottom panel 54 of the battery enclosure 52 and the top panel 61 of the tunnel 60 is selected to increase a clamping surface area between these two panels. The greater the clamping surface area, the greater the loads transferred between the two panels.
Referring now to FIGS. 8-9 , the structure 80 is described in greater details. The structure 80 may be made with tubular members, which may be made of a first material, such as steel, or other suitable materials. The use of steel may improve the strength of the tubular members as compared to other materials, for example. In the embodiment shown, the structure 80 includes left and right primary members 81, 82 interconnected to one another and defining four legs, namely, left and right front legs 81A, 82A and left and right rear legs 81B, 82B. In the embodiment shown, the left primary member 81 defines the left front leg 81A and the left right leg 81B, the right primary member 82 defines the right front leg 82A and the right rear leg 82B. In an alternative embodiment, the left front leg 81A, left rear leg 81B, right front leg 82A and right rear leg 82B may each be separate components joined together at a bracing member 86. In the embodiment shown, the structure 80 includes transverse member 87 that extends substantially transversally to the longitudinal axis L from a left end 87A to a right end 87B. Each of the four legs 81A, 82A, 81B, 82B define a respective end via which the structure 80 is secured to the tunnel 60 and sub-frame 70. More specifically, the left front leg 81A defines a left front end 81C secured to one of the front suspensions 45 (FIG. 4 ), the left rear leg 81B defines a left rear end 81D secured to the tunnel 60, the right front leg 82A defines a right front end 82C secured to the other of the front suspensions 45, and the right rear leg 82B defines a right rear end 82D secured to the tunnel 60. Moreover, a transverse member 87 is secured to the left and right primary members 81, 82. The transverse member 87 is further secured to the sub-frame 70 and is used to secure the structure 80 to the sub-frame 70.
In the embodiment shown, a left rear bracket 83 is secured to the left rear end 81D of the left rear leg 81B. Similarly, a right rear bracket 84 is secured to the right rear end 82D of the right rear leg 82B. The left and right rear brackets 83, 84 may be made of a second material, such as aluminum, or other suitable materials. The use of aluminum may reduce the weight of the left and right rear brackets 83, 84 as compared to other materials, for example. The second material of the left and right rear brackets 83, 84 may be different than the first material of the left and right primary members 81, 82. This use of dissimilar materials may provide an improved trade-off between the weight, strength and cost of the structure 80 when compared to a structure made of a uniform material, for example.
The left and right rear brackets 83, 84 define flanges for being secured to the side panels 62 of the tunnel 60. In some embodiments, the aluminum brackets 83, 84 are casted components, allowing for relatively intricate geometries. In some embodiments, the bracing member 86 may be a forged component, providing increased strength to take on greater loads from the steering column than casted components. In other embodiments, all of brackets 83, 84 and bracing member 86 may be either casted or forged.
Referring to FIG. 10 , a cross-sectional view of one of the left and right rear legs 81B, 82B, which are hollow and secured to the left and right rear brackets 83, 84 in the embodiment shown. An adhesive 85 is used to secure the left and right rear brackets 83, 84 to the left and right rear legs 81B, 82B. Put differently, the left and right rear brackets 83, 84 are secured to the left and right rear legs 81B, 82B via the adhesive 85. The adhesive 85 may be epoxy, acrylic, or any suitable adhesive used for adhesive bonding of metallic materials. The adhesive may be a 2-part system where a resin and a hardener or accelerator is mixed with the resin and left to cure at room temperature. The adhesive may be a 1-part system where the adhesive is oven-cured. The epoxy-based adhesives may provide superior bond strength whereas acrylic adhesives may be more tolerant to imperfection in surface finishes of substrates. In the embodiment shown, using two different materials for the members and the brackets may allow for costs and weight savings. Moreover, the adhesive 85 used for securing the brackets may avoid relying on brazing or welding. Typically, welding or brazing components together impart residual stresses within the materials of these components. To alleviate the residual stresses, the components are subjected to a heat treatment. Thus, securing the brackets via the adhesive 85, rather than via brazing or welding, may avoid imparting residual stresses within the materials and may avoid having to subject the structure 80 to a heat treatment. This may further reduce costs. The attachment between the brackets and the members may be free of a braze joint and weld joint.
Referring back to FIGS. 8-9 , in the depicted embodiment, the left primary member 81 extends upwardly in the vertical direction V from the left front end 81C to a left apex 81E, downwardly from the left apex 81E to a left elbow 81F, and downwardly from the left elbow 81F to the left rear end 81D. Similarly, the right primary member 82 extends upwardly in the vertical direction V from the right front end 82C to a right apex 82E, downwardly from the right apex 82E to a right elbow 82F, and downwardly from the right elbow 82F to the right rear end 82D. A distance in the transverse direction T between the left and right primary members 81, 82 increases from the left and right apexes 81E, 82E to the left and right elbows 81F, 82F. A second distance D2 defined between the left and right elbows 81F, 82F is greater than the width W2 (FIG. 5 ) of the rear portion 30B (FIG. 5 ) of the battery pack 30 to receive the rear portion 30B of the battery pack 30 between the left and right rear legs 81B, 82B.
In the present embodiment, the left primary member 81 is secured to the right primary member 82 via bracing member 86. The bracing member 86 may be made of the second material, which may be aluminum, and secured to the left and right primary members 81, 82 via the adhesive 85 as described herein above with reference to FIG. 10 . Herein, the bracing member 86 is located proximate the left and right apexes 81E, 82E, but may alternatively located at the left and right apexes 81E, 82E or at another suitable location.
Referring to FIG. 6 , a third distance D3 along the vertical direction V between the left and right elbows 81F, 82F and the top panel 61 of the tunnel 60 is greater than a height H of the battery pack 30 taken along the vertical direction V. This may allow the structure 80 to fit over the battery pack 30, by accommodating its width W2 and its height H. In the present embodiment, the left and right elbows 81F, 82F are substantially longitudinally aligned with the intersection between the front portion 30A and the rear portion 30B of the battery pack 30.
As shown in FIGS. 8-9 , the structure 80 includes a transverse member 87 that extends substantially transversally to the longitudinal axis L from a left end 87A to a right end 87B. The transverse member 87 is secured to both of the left and right primary members 81, 82 via left and right connecting members 88, 89 made of the second material, which may be aluminum. An adhesive may be used to bond the left and right connecting members 88, 89 to both of the left and right primary members 81, 82, more specifically, the left and right rear legs 81B, 82B, and to the transverse member 87. The connecting members 88, 89 may be casted components.
The left end 87A of the transverse member 87 is secured to one of the foot rests 63 and the right end 87B of the transverse member 87 is secured to the other of the foot rests 63. Thus, the two foot rests 63 may be secured to one another via the transverse member 87. As illustrated in FIG. 8 , the left and right ends 87A, 87B of the transverse member 87 are secured proximate front ends of the foot rests 63 proximate to the sub-frame 70 and to or proximate outer edges of the foot rests 63. Stated differently, securing locations between the first and second ends 87A, 87B of the transverse member 87 and the foot rests 63 are separated from (e.g., disposed as far as possible from) the tunnel 60 thereby increasing a distance between those securing locations. In turn, this may provide an increase stiffness to the foot rests 63. More specifically, the foot rests 63 are substantially cantilevered from the side panels 62 of the tunnel and, thus, may be subjected to flexion about the longitudinal axis L. Securing both foot rests 63 to the transverse member 87 may reduce this flexion, thereby increasing a perceived stiffness of the foot rests 63 to the user. Moreover, the attachment of the foot rests 63 to the transverse member 87 may create a load path that extends from the tunnel 60, along the foot rests 63, to the transverse member 87, to the structure 80, and to the front suspensions 45. The electric snowmobile 10 may thus be better at handling the loads imparted to it during use because of this transverse member 87.
Securing the first and second ends 87A, 87B of the transverse member 87 to the foot rests 63 may provide room for the front portion 30A of the battery pack 30. As noted above, the width W1 of the front portion 30A of the battery back 30 may be greater than the width W2 of the rear portion 30B, and therefore extending the transverse member 87 beyond the width of the tunnel 60 may provide additional room to accommodate the front portion 30A within the structure 80.
As shown in FIG. 9 , a secondary left member 90 and a secondary right member 91 are used to secure a left leg 87C of the transverse member 87 to the left rear leg 81B of the left primary member 81 and to secure a right leg 87D of the transverse member 87 to the right rear leg 82B of the right primary member 82. The secondary left and right members 90, 91 may increase a stiffness of the structure 80 and, more particularly, may increase a stiffness of the transverse member 87. Connecting members made of the second material, such as aluminum, may be used to secure the secondary left and right members 90, 91 to the left and right primary members 81, 82. As depicted in FIG. 8 , the left and right members 90, 91 may be further connected to the sub-frame 70. The connection between the sub-frame 70 and the left and right legs 87C and 87D may assist with countering moment loads exerted on the structure 80 by loads received by the foot rests 63 during riding.
The structure 80, including the left and right primary members 81, 82, the transverse members 87, the brackets 83, 84, the connecting members 88, 89, the bracing member 86, and the left and right secondary members 90, 91, may become a single integral unit. The structure 80 may be secured to the frame 12 at six different locations, each corresponding to a respective one of the ends 81C, 81D, 82C, 82D, 87A, 87B. The structure 80 may be secured to the tunnel 60 and the sub-frame 70 as a whole single unit lowered down over the battery pack 30.
In some embodiments, fasteners such as bolts may be used to connect the structure to the tunnel 60 and the sub-frame 70. For example, each of the ends 81C, 82C may include a threaded hole to receive a bolt extending through a respective one of the front suspensions 45 to connect to the front suspensions 45. The threaded holes may extend axially into the left and right primary members 81, 82 at the ends 81C, 82C, respectively. Similarly, each of the ends 87A, 87B may include an threaded hole extending axially into the transverse member 87 at a respective one of the ends 87A, 87B. These threaded holes may receive bolts extending through the foot rests 63. The left and right rear brackets 83, 84 may also be coupled to the tunnel 60 using fasteners.
Referring now to FIG. 11 , in the present embodiment, the structure 80 includes shear plates 92 each disposed on a respective side of the structure 80. The shear plates 92 connect the transverse member 87 to the sub-frame 70. The shear plates 92 are secured to the left and right legs 87C, 87D proximate the left and right ends 87A, 87B of the transverse member 87. The shear plates 92 may limit a deflection of the left and right legs 87C, 87D of the transverse member 87 along the longitudinal axis L. Each of the shear plates 92 may be secured to a respective one of the left and right legs 87C, 87D of the transverse member 87 at three securing locations distributed vertically along a length of the left and right legs 87C, 87D. Any suitable number of securing locations is contemplated. Each of the shear plates 92 may be secured to the sub-frame along perimeters of the shear plates 92.
In the present embodiment, the structure 80 may be removed from the sub-frame 70 and the tunnel 60 to access the battery pack 30. This may be useful if a replacement or repair of the battery pack 30 is required. To assemble the electric snowmobile 10, the battery pack 30 may be disposed over the tunnel 60 and the sub-frame 70. Then, the structure 80 may be lowered vertically over the battery pack 30 and be secured to the tunnel 60 and sub-frame 70. As explained above, the two elbows of the structure 80 are sufficiently spaced apart and elevated to accommodate the battery pack 30.
Still referring to FIG. 11 , in the embodiment shown, the steering column 19 defines a bend or elbow 19A to accommodate the front portion 30A of the battery pack 30. This may allow to increase a size of the battery pack 30 without interference with the steering column 19.
Referring now to FIG. 12 , an alternate embodiment of the structure is shown at 180. For the sake of conciseness, only features differing from the structure 80 described above are described below.
The structure 180 includes the left and right primary members 81, 82 defining the four legs 81A, 81B, 82A, 82B. The left and right primary members 81, 82 are secured together via two secondary transverse members 181, 182 extending generally transversally to the longitudinal axis L.
Referring now to FIG. 13 , an alternate embodiment of the structure is shown at 280. For the sake of conciseness, only features differing from the structure 80 described above are described below.
The structure 280 includes the left and right primary members 281, 282 defining the four legs 81A, 81B, 82A, 82B. In the embodiment shown, the left and right primary members 281, 282 are secured together at an apex 281A of the structure 280. In other words, the left and right primary members 281, 282 cross one another at the apex 281A. The left and right primary members 281, 282 are secured together via two secondary transverse members 283, 284 extending generally transversally to the longitudinal axis L. The two secondary transverse members 283, 284 are located above one another and may be parallel to one another.
Referring now to FIG. 14 , an alternate embodiment of the structure is shown at 380. For the sake of conciseness, only features differing from the structure 80 described above are described below.
The structure 380 includes the two primary members 381, 382 defining the four legs 81A, 81B, 82A, 82B. In the embodiment shown, the two primary members 381, 382 are offset from one another relative to the longitudinal axis L and define U-shapes and apexes 381A, 382A. The two primary members 381, 382 are secured together at their apexes 381A, 382A via a plate 383. The two primary members 381, 382 are secured together via a secondary transverse members 384 extending generally transversally to the longitudinal axis L.
In some embodiments, two or more members of the structures 180, 280, 380 may be secured together using fasteners, welds and/or adhesives. Optionally, brackets may be used to help secure the members.
Referring now to FIGS. 15-18 , an embodiment of a heat exchanger is shown at 102. The heat exchanger 102 is herein mounted to the bulkhead 71 of the sub-frame 70. The heat exchanger 102 may be removable from the bulkhead 71. The heat exchanger 102 faces the spacing that is defined by the tunnel 60 and that receives the drive track 15 (FIG. 1 ). The heat exchanger 102 may thus be exposed to snow and cold air circulating around the drive track 15. The heat exchanger 102 covers a major portion of a surface of the bulkhead 71 exposed to the spacing. In the embodiment shown, the heat exchanger 102 covers more than 50%, and optionally as much as 90% of the surface of the bulkhead 71 exposed to the spacing.
Referring more particularly to FIGS. 17-18 , the heat exchanger 102 includes two plates namely a first plate 103 and a second plate 104 mounted to the first plate 103. The first plate 103 is mounted to the bulkhead 71. The first plate 103 may contact the bulkhead 71. The bulkhead 71 may include a cut-out portion at a location where the heat exchanger 102 is positioned. As such, the first plate 103 is mounted to the bulkhead 71 along its periphery such that the first plate 103 forms the surface of the bulkhead 71 that faces the motor 26. The second plate 104 is secured to the first plate 103 and may be sealingly engaged to the first plate 103. The second plate 104 is exposed to the spacing receiving the drive track 15. The second plate 104 is embossed to define one or more channels 105 for flowing the liquid coolant of the cooling system 100 (FIG. 1 ). The one or more channels 105 is thus defined between the first plate 103 and the second plate 104. The one or more channels 105 is in fluid flow communication with an inlet 1021 of the exchanger 102 and with an outlet 1020 of the heat exchanger 102. The inlet 1021 and the outlet 1020 of the heat exchanger 102 are in fluid flow communication with the liquid coolant circuit 101 (FIG. 1 ) of the electric snowmobile 10.
In use, the liquid coolant flows through the different components (e.g., electric motor 26, battery pack 30) to pick up heat from said components. The liquid coolant then flows through the one or more channels 105 of the heat exchanger 102 via the inlet 1021 and outlet 1020. Heat of the liquid coolant may be transferred to ambient air via the one or more channels 105, via internal convection within the one or more channels 105, conduction through the second plate 104, and external convection with the ambient air.
As better illustrated in FIG. 15 , the first and second plates 103, 104 of the heat exchanger 102 are secured to the bulkhead 71 at a plurality of locations 106 distributed around perimeters of the first and second plates 103, 104. The heat exchanger 102 may therefore increase a stiffness of the bulkhead 71. The first and second plates 103, 104 may be made of a metallic material, such as stainless steel or aluminum, and may each have a thickness of about 1.6 mm.
The disclosed frame 12 and structure 80 of the electric snowmobile 10 may provide the necessary stiffness and may be lighter than existing snowmobile configurations. It may be more cost efficient and easier to manufacture. The stiffness in torsion of the tunnel 60 may be improved by the battery pack 30, and more particularly by the bottom panel 54 of said battery pack 30. The structure 80 may be adequately sized to accommodate the battery pack 30 while providing the required stiffness.
In the context of the present disclosure, the expression “about” includes variations of plus or minus 10%.
The embodiments described in this document provide non-limiting examples of possible implementations of the present technology. Upon review of the present disclosure, a person of ordinary skill in the art will recognize that changes may be made to the embodiments described herein without departing from the scope of the present technology. Yet further modifications could be implemented by a person of ordinary skill in the art in view of the present disclosure, which modifications would be within the scope of the present technology.

Claims

1. An electric snowmobile, comprising:

a frame extending along a longitudinal axis between a front end and a rear end of the frame, the frame including a tunnel at least partially enclosing a spacing receiving a drive track, a sub-frame disposed forward of the tunnel relative to the longitudinal axis, the sub-frame supporting a front suspension;

an electric motor mounted to the frame;

a battery pack mounted over the tunnel and at least partially disposed rearward of the electric motor relative to the longitudinal axis, the battery pack having a front portion and a rear portion, a width of the front portion relative to a transverse direction normal to the longitudinal axis being greater than a width of the rear portion; and

a structure disposed over the sub-frame and over the front portion of the battery pack, the structure defining at least four legs ending at four ends, the at least four legs including two front legs secured to the front suspensions and two rear legs secured to the tunnel, each of the two rear legs defining a respective one of two elbows and a respective one of two rear ends of the four ends, the two elbows located above the two rear ends, a distance along the transverse direction between the two elbows being greater than the width of the rear portion of the battery pack to receive the rear portion between the two rear legs.

2. The electric snowmobile of claim 1, wherein a distance along a vertical direction being normal the transverse direction between the two elbows and a top wall of the tunnel is greater than a height of the battery pack taken along the vertical direction.

3. The electric snowmobile of claim 1, wherein the two elbows are located at an intersection between the front portion and the rear portion of the battery pack.

4. The electric snowmobile of claim 1, wherein the at least four legs are defined by two members each extending upwardly from a front end to an apex and downwardly from the apex to a respective one of the two rear ends.

5. The electric snowmobile of claim 4, wherein the two members are secured to one another proximate the apexes.

6. The electric snowmobile of claim 5, wherein the structure includes a bracing member connecting the two members.

7. The electric snowmobile of claim 1, wherein the structure includes a transverse member extending substantially transversally to the longitudinal axis from a left end to a right end, the transverse member secured to the two rear legs.

8. The electric snowmobile of claim 7, comprising a left foot rest secured to a left side of the tunnel and a right foot rest secured to a right side of the tunnel, the left foot rest and the right foot rest extending along the longitudinal axis from the sub-frame towards the rear end of the frame, the left end of the transverse member secured to the left foot rest proximate the sub-frame, the right end of the transverse member secured to the right foot rest proximate the sub-frame.

9. The electric snowmobile of claim 7, wherein the transverse member is secured to two rear legs via connecting members.

10. The electric snowmobile of claim 7, comprising a left shear plate connecting the transverse member to the sub-frame and a right shear plate connecting the transverse member to the sub-frame.

11. An electric snowmobile, comprising:

a frame extending along a longitudinal axis between a front end and a rear end of the frame, the frame including a tunnel at least partially enclosing a spacing receiving a drive track, and a sub-frame disposed forward of the tunnel relative to the longitudinal axis, the sub-frame supporting a front suspension;

an electric motor mounted to the frame; and

a structure disposed over the sub-frame, the structure including members interconnected to one another, the members made of a first material, a bracket secured to an end of a member of the members via an adhesive, the bracket secured to the tunnel, the bracket made of a second material different than the first material.

12. The electric snowmobile of claim 11, wherein the first material is steel and the second material is aluminum.

13. The electric snowmobile of claim 11, wherein the adhesive is one or more of an epoxy and an acrylic.

14. The electric snowmobile of claim 11, wherein the structure defines two fore ends and two rear ends, the bracket including two brackets each secured to a respective one of the two rear ends, the two brackets secured to the tunnel.

15. The electric snowmobile of claim 11, wherein the structure defines two fore ends each secured to a respective one of a right suspension and a left suspension of the front suspension.

16. The electric snowmobile of claim 11, wherein the members include a left member extending upwardly from a front left end to a left apex and from the left apex downwardly to a rear left end, a right member extending upwardly from a front right end to a right apex and downwardly from the right apex to a rear right end.

17. The electric snowmobile of claim 16, wherein the right member is secured to the left member proximate the left apex and the right apex.

18. The electric snowmobile of claim 16, wherein the structure includes a bracing member connecting the left member to the right member, the bracing member secured to the left member proximate or at the left apex and secured to the right member proximate or at the right apex.

19. The electric snowmobile of claim 16, wherein the structure includes a transverse member extending substantially transversally to the longitudinal axis from a left end to a right end, the transverse member secured to the left member and to the right member.

20. The electric snowmobile of claim 19, comprising a left foot rest secured to a left side of the tunnel and a right foot rest secured to a right side of the tunnel, the left foot rest and the right foot rest extending along the longitudinal axis from the sub-frame towards the rear end of the frame, the left end of the transverse member secured to the left foot rest proximate the sub-frame, the right end of the transverse member secured to the right foot rest proximate the sub-frame.

21. The electric snowmobile of claim 19, wherein the transverse member is secured to the left member and to the right member via left and right connecting members made of the second material, the left and right connecting members secured to the transverse member and to the left and right members via the adhesive.

22. The electric snowmobile of claim 19, wherein the left member defines a left elbow and the right member defines a right elbow, the transverse member secured to the left member proximate or at the left elbow and secured to the right member proximate or at the right elbow.

23. The electric snowmobile of claim 19, comprising a left shear plate connecting the transverse member to the sub-frame and a right shear plate connecting the transverse member to the sub-frame.

24. A structure for an electric snowmobile having a battery pack having a front portion and a rear portion, a width of the front portion relative to a transverse direction normal to a longitudinal axis of the electric snowmobile being greater than a width of the rear portion, the structure comprising:

two front legs to secure to front suspensions of the electric snowmobile; and

two rear legs to secure to a tunnel of the electric snowmobile, each of the two rear legs defining a respective one of two elbows and a respective one of two rear ends, the two elbows located above the two rear ends, a distance along the transverse direction between the two elbows being greater than a width of the rear portion of the battery pack to receive the rear portion between the two rear legs.