Supreme Court ENGINEER’S VIEWS ON MOWER

Press, Volume XCVIII, Issue 28958, 28 July 1959, Page 19

Supreme Court ENGINEER’S VIEWS ON MOWER

“Hydraulic Concept Not Unsound”

It was not the concept of a hydraulic mower that was unisound but the application of the principle to an ordinary farm machine, a technical witness said in the Supreme Court yesterday when the hearing of the dispute between Pyramid Machines, Ltd. and W. H. Price and Son, Ltdcontinued before Mr justice Adams. The witness, Robin Shirer Bisley, an agricultural engineer, called by Price and Son, was cross-examined at length by Mr R. W. Edgley, counsel for Pyramid Machines, on his statement that the Pyramid mower was “fundamentally unsound in concept.” “Do you mean by that statement that the use of an hydraulic drive is rendered impossible by some law of physics’” asked Mr Edgley. Witness: No.

Or do you mean the design of the mower did not take into account some or all of the factors you enumerated?—Yes. You regard the design itself as fundamentally bad? —Quite, from an economic and manufacturing point of view. Do you really mean it could be done perfectly well the way the Pyramid mower is made, but not at the price?—No. Not “Basically Unsound” Bisley did not agree that it could be done “at a price." Under those circumstances he would still consider the design unsatisfactory in respect to its operation. Mr Edgley: It’s not the actual concept of an hydraulic mower you consider unsound?—No. Is is the concept of the transmission of rotary power that you regard as unsound?—That is one point. Is that your most important point?—No. There are other considerations.

Bisley said he did not regard the transmission of rotary power as “basically unsound.” What feature in this mower do you regard as fundamentally unsound?—The application of this principle to an ordinary farm machine.

Isn’t the only objection you raise there the question of cost'. —Primarily, and also I considei a better result may be more simply achieved by a free piston reciprocating type of motor, which to a degree would justify the extra expense resulting from the use of an hydraulic transmission instead of a mechanical transmission. The free piston type of motor would obviously be cheaper, said Bisley. Such a motor would also cause less vibration, but only with the addition of a balancing device. It is expected that Bisley will be the last witness for the defendant, but witnesses for the plaintiff will be recalled to give evidence in rebuttal before counsel make their final addresses.