GB2390837A

GB2390837A - Snowmobiles

Info

Publication number: GB2390837A
Application number: GB0215259A
Authority: GB
Inventors: Damian Stuart Pinson; Michael John Robertson Coats
Original assignee: SNOWDOME Ltd
Current assignee: SNOWDOME Ltd
Priority date: 2002-07-02
Filing date: 2002-07-02
Publication date: 2004-01-21
Anticipated expiration: 2022-07-02
Also published as: GB0215259D0; GB2390837B

Abstract

A snowmobile comprises a ground contacting track 18, steerable skids 24 at the front, and a drive train 24 arranged to provide drive to the track 18 to drive the snowmobile. A throttle control switch 35 allows a driver to control the drive to the track 18. The drive train comprises a battery 32 arranged to store electric energy, an electric motor 22 arranged to be driven by the battery 32, and a controller 34 arranged to receive signals from the throttle control switch 35 and to control operation of the motor 22 in response thereto.

Description

SNOWMOBILES

The present invention relates to snowmobiles, and in particular to the drive trains of snowmobiles.

Snowmobiles have been known for a long time as a convenient mode of transport over snow where conventional wheeled vehicles cannot be controlled well and suffer from a lack of traction. Snowmobiles generally include one or more tracks which are driven to provide drive for the 10 snowmobile, and one or more skids which are steerable to provide steering. Snowmobiles can be used as recreational vehicles, or for utilitarian purposes. Since they are designed for use in snow and are therefore generally considered to be outdoor vehicles, snowmobiles have generally been designed to travel relatively long distances, and generally 15 have been powered by two- or four-stroke internal combustion engines.

The present invention aims to provide a snowmobile which is suitable for use in indoor snow centres. Such centres are known for use by skiers and snowboarders, and the present invention aims to enable their use by 20 snowmobile users. It will be appreciated that in such an environment it is desirable for the emissions and noise produced by the snowmobile to be reduced as far as possible.

Accordingly the present invention provides a snowmobile comprising a 25 ground contacting track, at least one steerable skid, a drive train arranged to provide drive to the track to drive the snowmobile, and driver input means to allow a driver to control the drive to the track, wherein the drive train comprises a battery arranged to store electric energy and an electric motor arranged to be driven by the battery, and control means

( arranged to receive signals from the driver input means and to control operation of the motor in response thereto.

Preferably the electric motor is operable as a generator to enable 5 regenerative charging of the battery.

Preferably the snowmobile further comprises a body defining a drive train compartment in which the drive train is housed.

10 Preferably the motor is connected to the track through a gearbox.

Preferably the motor is connected to the gearbox by means of a drive shaft. Preferably the motor has an output shaft which is arranged transversely to the snowmobile, and the drive shaft is parallel to the output shaft. Preferably the battery is located to the rear of the motor and 15 the gearbox. Preferably the battery is located to the front of the motor and the gearbox.

Preferably the snowmobile further comprises a further battery, and one of the batteries is located to the rear of the motor and the gearbox and the 20 other of the batteries is located to the front of the motor and the gearbox.

Preferably the snowmobile includes two batteries, and further comprises a steering column arranged to connect a driver steering input member to the steerable skid, wherein the steering column is arranged to extend between 25 two of the batteries. Preferably said two batteries are arranged one on each side of the snowmobile and define a gap therebetween through which the steering column extends.

Preferably the control means comprises a control unit which is located at 30 the front end of the drive train compartment. Preferably the snowmobile

/ further comprises at least one contactor and the contactor is located in the drive train compartment between the control unit and at least one of the batteries. S The motor may drive the track via a gearbox, which preferably includes a brake, such as a disk brake.

Preferred embodiments of the present invention will now be described by way of example only with reference to the accompanying drawings in 10 which: Figure 1 is a schematic representation of a snowmobile according to the invention. IS Referring to Figure 1, a snowmobile comprises a body 10 having a front portion 12 forming a housing for many of the components of the snowmobile, and a rear portion 14 having a seat 16 on it. The body is supported at the rear on a track 18, each of which is connected to the body by a front drive wheel 20 and a rear guide wheel 22. The front of 20 the body is supported on a pair of steerable skids 24.

A drive train 26 is provided to drive the drive wheel 20 of the track 18.

In Figure 1, the drive train is only shown schematically. The actual layout will be described below with reference to Figure 2. The drive train 25 comprises a 50KW D. C. electric motor 22, a gearbox 24 which is connected to the motor 22 by means of a drive chain 26, and a drive shaft 28 which connects the output from the gearbox 24 to the drive wheel 20.

A disk brake 30 is provided in the gearbox 24 to enable braking of the snowmobile. A number of rechargeable batteries 32, only one of which is 30 shown in Figure 1, are provided to store charge for driving the motor 22.

( A programmable control unit 34 is connected to the battery 32, the motor 22 and the gearbox 24, and controls the operation of the motor. The ECU monitors the state of charge of the battery 32 and the speed of the motor 22, and also receives drive torque demand input from a throttle switch 35, 5 which is mounted on a set of handlebars 36 arranged to provide a steering input for steering the skids 24. A brake lever 38 is also provided on the handlebars 36 and is connected to the disk brake 30 to enable driver to brake the snowmobile. Contactors 41 are provided to control the motor so that it can be operated forwards or in reverse, or as a generator. The 10 contactors 41 are controlled by the control unit 34.

In operation the control unit 34 controls the motor 22 so as to provide a driving torque corresponding to the drive demand of the driver, as determined by the position of the throttle switch 35. If the driver is 15 demanding no driving torque the control unit 34 switches the motor 22 to a regenerative braking mode in which, if the snowmobile is moving, the motor will be driven to rotate by the drive chain 26 which will be driven via the gearbox 24 from the track l 8. Under these circumstances the control unit 34 is arranged to control the motor 22 so that it acts as a 20 generator and produces electrical power which is stored in the battery 32.

Referring to Figure 2, the handlebars 36 are attached to the top of a steering column 37 which is inclined to the vertical and slopes upwards to the rear so that its upper end 37a is located slightly forward of the front 25 of the seat 16 and its lower end 37b is further forward, closer to the steering input to the skids 24. The region of the body 10 to the front of the seat forms a drive train compartment 42 having its rear end approximately level with the front of the seat 16 and its front end at the front of the snowmobile.

As shown in Figure 2, there are four 12V batteries 32 which are connected up so as to provide a 48V supply. Two of these 32a, 32b are located at the rear of the drive train compartment 42 just to the front of the seat 16. The motor 22 is located to one side of the drive train 5 compartment 42 just in front of one of these batteries 32a and is arranged transversely, i.e. with its output shaft 22a extending transversely of the snowmobile. A gearbox drive shaft 44 is arranged transversely just to the front of the motor, having one end connected to the motor output shaft 22a by the drive chain 26 and the other end connected to the gearbox 24 10 which is located adjacent to the motor 22 and slightly forward of it. The motor 22 and motor are behind the steering column 37, and the gearbox drive shaft 44 is also just behind the steering column 37. Two further batteries 32c, 32d are located side by side in front of the motor 22 and gearbox 24, with a gap between them through which the front lower end 15 of the steering column passes. The contactors 41 are located to the front of the forwardmost batteries 32c, 32d, and the control unit 34 is at the very front end of the drive train compartment 42 to the front of the contactors 41.

20 This layout of the various components is beneficial in that it provides a good weight distribution, in particular by providing an even distribution of the batteries 32 which are relatively heavy components. It is also very compact, taking up no more space than a conventional petrol engine drive train. It also allows easy access to the various components for 25 maintenance and replacement.

Claims

1. A snowmobile comprising a ground contacting track, at least one steerable skid, a drive train arranged to provide drive to the track to drive the snowmobile, and driver input means to allow a driver to control the 5 drive to the track, wherein the drive train comprises a battery arranged to store electric energy, an electric motor arranged to be driven by the battery, and control means arranged to receive signals from the driver input means and to control operation of the motor in response thereto.

10

2. A snowmobile according to claim I wherein the electric motor is operable as a generator to enable regenerative charging of the battery.

3. A snowmobile according to claim 1 or claim 2 further comprising a body defining a drive train compartment in which the drive train is 15 housed.

4. A snowmobile according to claim 3 wherein the motor is connected to the track through a gearbox.

20

5. A snowmobile according to claim 3 wherein the motor is connected to the gearbox by means of a drive shaft.

6. A snowmobile according to claim 5 wherein the motor has an output shaft which is arranged transversely to the snowmobile, and the 25 drive shaft is parallel to the output shaft.

7. A snowmobile according to any of claims 4 to 6 wherein the battery is located to the rear of the motor and the gearbox.

- (

8. A snowmobile according to any of claims 4 to 6 wherein the battery is located to the front of the motor and the gearbox.

9. A snowmobile according to any of claims 4 to 6 further comprising 5 a further battery, wherein one of the batteries is located to the rear of the motor and the gearbox and the other of the batteries is located to the front of the motor and the gearbox.

10. A snowmobile according to any foregoing claim including two 10 batteries, and further comprising a steering column arranged to connect a driver steering input member to the steerable skid, wherein the steering column is arranged to extend between two of the batteries.

11. A snowmobile according to claim 10 wherein said two batteries are IS arranged one on each side of the snowmobile and define a gap therebetween through which the steering column extends.

12. A snowmobile according to claim 3 or any claim dependent thereon wherein the control means comprises a control unit which is located at the 20 front end of the drive train compartment.

13. A snowmobile according to claim 12 further comprising at least one contactor arranged to control operation of the motor, wherein the contactor is located in the drive train compartment between the control 25 unit and at least one of the batteries.

14. A snowmobile substantially as hereinbefore described with reference to the accompanying drawings.