CLEVER JACKING SYSTEM

Timaru Herald, Volume CXXV, Issue 18552, 26 April 1930, Page 15 (Supplement)

CLEVER JACKING SYSTEM

NEW ZEALAND INVENTION. An exceptionally Interesting device, the auto-electric hydraulic jack, invented by tne well-known New Zealand racing-motorist Mr Howard Nattrays was recently tested by Mr G. R. Robertson, engineer to the Auckland Automobile Association, who has issued a certificate as to the performance of the device. As ifs name suggests, the jack is partly electrical and partly hydraulic, and the system on which it operates is similar in the main to that of the ordinary hydraulic brake, except that the motive power provided by the starter motor instead of by the driver’s foot as is the case with the hydraulic brake. Method of Operation. To provide the necessary power for the jack, the existing starter motor of any car is used, and is connected by a spearate switch with four volts of the six-volt battery. A small pump of i inch bore and 1 inch stroke is connected with one end of the starter motor, while three pints of water is carried in a reservoir under the bonnet. The water is pumped from the reservoir to a distributor valve in a handy position to the driver, who is thus able to operate the system, and lift any wheel or any combination of the four wheels without leaving the driving seat. To jack up the car It is only necessary to close the by-pass, turn the switch on the dash-board to the position required and press the starter. The device ia simple in operation, and costs little more than on ordinary type of hydraulic jack. Moreover it is claimed to cost nothing to operate, and uses little current. Since it will raise any of the wheels at the same time, it would prove a decided convenience when the wheels were being washed and the brakes adjusted, or while tyres were being changed or chains fitted. When the plunger is in the normal position, the lowest part of the jack is level with the bottom of the front axle, and thus does not interfere with the clearance. The whole fitting has been standardised down to the clamp for fitting the device to the axles, and this casting Is made to fit any make of car. The apparatus is not unsightly, and no part projects to interfere with the steering or the shock-absorbers. The casual observer would probably mistake the Jacks for shock-absorbers of some hydraulic type, as they are particularly neat in design. Official A.A.A. Report. The efficiency of the system will be recognised from the following figures quoted in the A.A.A. official report. The A.A-A. engineer tested the jack as fitted to a sedan car weighing 1 ton scwt. lqr. The time taken to lift any one wheel was 9 seconds; both front wheels, 16.55.; both rear wheels, 175.; both near side wheels, 18s.; both offside wheels, 18s.; all four wheels, 21s. With three twelve-stone men in the rear seat, the rear wheels were lifted in 19.55.; and both off-side wheels were lifted in 215., with the same three men standing on the running board. In all lifts the tyres were raised two inches clear of the ground. In all, 22 lifts were made in 19 minutes, and the report states that at the conclusion of the test the starter was operated without there bebig any noticeable decrease In battery efficiency.