FREE=WHEELING

Hawera Star, Volume LI, 20 February 1932, Page 12

FREE=WHEELING

NEAY AUSTRALIAN DEVICE. ADAPTABLE TO ANY CAR. An interesting accessory which can be adapted to almost every make <.i car has just appeared in this market. The fitting in question is operactu . . the suction in the engine induction pipe, the force of which is used to operate a piston, which, in turn, through tiie medium of a connecting rod and a flexible connection running over a pulley causes the clutch to disengage whenever the driver’s foot is removed from the accelerator pedal. The effect of this is that unless the engine is actually driving the car. the transmission between the engine and the rear wheels is broken at the clutch, so that the vehicle ‘‘coasts” with the force of its momentum without the ordinary retarding effect produced when the wheels are, so to speak, driving the engine. It is claimed by the distributors that, apart from other advantages, an average saving of fuel or 25 per cent, is obtained. It is, of course, well-known that free-wheeling attachments enable a much greater petrol mileage to be attained, and the saving claimed in respect of the accessory under review is not excessive in view of the results which have been verified in regard to the type of freewheel fitting which is incorporated in the gearing. The question which at once arises is: “To what extent may the clutch suffer?” For it an old axiom of motoring that slipping of the clutch and coasting with the clutch belli out are both harmful practices. In regard to this the distributors of this novel equipment, known as the “Simplicitv Freewheel,” point out that the question of clutch-slipping does not arise, in that the dutch, when actuated by this mechanism, is held in a fully disengaged position until the driver again presses down on the accelerator pedal. For that reason there can be no wear

and tear of the frictional surfaces of the clutch.

The only controversial matter is the possible effect on the withdrawal mechanism of the clutch. In regard to this, it is stated that experiment has shown that with modern types of cars which generally have a ball-bearing in the throw-out mechanism, the amount of wear due to coasting with the clutch disengaged is negligible. The •distributors state that the manufacturers, whose headquarters are in Meibourne, have tested the fitting on a heavy ear for almost a year and that subsequent dismantling and close examination of the clutch revealed no appreciable wear. The device lias the merit of great simplicity. It comprises a vacuum cylinder.’ in which fits an aluminium piston, whose connecting rod is attached to the clutch pedal by means of a flexible steel cable passing over a pulley appropriately placed. From this cylinder a small pipe runs to the induction pipe, and there is also another flexible pipe connection t<o a control valve, winch is fixed conveniently on the steering pillar or the instrument board. When in the “oft” position air is free to flow through this pipe, and so there is no vacuum effect in the cylinder, but when this valve is closed there is strong suction, because of the vacuum effect in the induction pipe, which is at it.s highest when the throttle is shut in the idling position. At the point where the pipe from the free-wheel cylinder joins the induction line there is fixed another control valve in the form of a closefitting plunger, the latter being connected by a short flexible cable to the operating rod of the throttle. The effect is' that when the throttle is in the closed position the suction in the induction pipe is transmitted to the evlinder. with the result that the piston is drawn up. thus completely disengaging the clutch. But when the accelerator pedal is depressed the plunger of the valve is sucked iorwaid and thus closes the suction line, whereupon the clutch spring reasserts itself and the clutch engages smoothly. An important point- is that hue operation of the attachment may.be discontinued at will simply by mnnipu-i

lution of the control valve. The cost of the attachment, together with fitting charges, is under £/. At the invitation of the joint local distributors, the writer drove a car equipped with the fitting. It was found that the car handled easily, and that after a little practice there was no difficulty in operating the accelerator.