Motor Vehicle

Abstract

A motor vehicle 5 is disclosed having an engine 10 used to drive a number of ancillary devices 12, 14, 16 and 18 via an ancillary drive 11. An electronically controlled disengageable connection 21 is provided to selectively disengage the drive from the engine 10 to the ancillary drive 11 when a high power output is required from the engine 10 to drive the motor vehicle 5. When the ancillary drive 11 is disengaged a source of motive power 12 is used to power the ancillary devices 14, 16 and 18 so as to maintain their operation.

Description

BRIEF DESCRIPTION OF THE DRAWING

The invention will now be described by way of example with reference to the accompanying drawing of which:

FIG. 1 is a side view of a motor vehicle according to the invention;

FIG. 2 is a schematic front view of an engine forming part of a motor vehicle according to the invention; and

FIG. 3 is a plan view of the engine shown in FIG. 2.

Claims

1. A motor vehicle having an internal combustion engine, an ancillary drive to driveably connect one or more ancillary devices to an output from the engine, a disengageable connection interposed between the output from the engine and the ancillary drive to permit the ancillary drive to be disengagaged from the engine, and a controller to control the disengageable connection, wherein when at least one vehicle operating condition indicating that a high power output is required from the engine is present, the disengageable connection is disengaged and a source of motive power driveably connected to the ancillary drive is energised to drive the one or more ancillary devices.

2. A motor vehicle as claimed in claim 1 wherein the disengageable connection is a clutch controlled by the controller.

3. A motor vehicle as claimed in claim 1 wherein the source of motive power is one of an electric machine, a hydraulic motor and a steam powered motor.

4. A motor vehicle as claimed in claim 1 wherein the source of motive power is an electric machine forming one of the one or more ancillary devices driveably connected to the engine by the ancillary drive.

5. A motor vehicle as claimed in claim 4 wherein the electric machine is a motor/generator used to start the engine.

6. A motor vehicle as claimed in claim 1 wherein the one or more ancillary devices comprises at least one of a power assisted steering pump, an air-conditioning compressor, an engine coolant pump and an electrical generator.

7. A motor vehicle as claimed in claim 1 wherein the vehicle operating condition is one of an input from an accelerator pedal indicating that a high power output is demanded, a signal from a driver operated switch used to request a high power output from the engine and an indication that the motor vehicle is unable to maintain the current forward speed even though an accelerator pedal is fully depressed.

8. A motor vehicle as claimed in claim 1 wherein the output from the engine is a crankshaft of the engine.

9. A motor vehicle as claimed in claims 1 wherein the controller is part of a control system used to control operation of the engine and to energise the source of motive power.