“20. The pump and control system with which I am concerned in this action operates in what was referred to as “manual mode”
“Control Means a) coupled to the drive means b) for adjusting the stroke length of the pistons between their top dead centre and their bottom dead centre respectively c) in response to the desired flow rate of the liquid delivered at the outlet of the pumping apparatus, d) with the stroke volume (i.e., the amount of liquid displaced during a pump cycle) being decreased when the flow rate is decreased and vice versa, e) such that pulsations in the flow of the liquid delivered to the output of the pumping apparatus are reduced.”
“24. In such an arrangement [i.e. that described in the last sentence of the col.10 passage] it seems to me clear that the machine is required to fix the pumping frequency having regard to the flow rate and stroke volume specified by the user. Accordingly, the response called for by feature (c) of the claim is not present. Such a mode of operation, if the only mode of operation of the machine would not infringe the claim. I read the words ‘free selection’ as being deliberately chosen in antithesis to the adjustment called for by the claim.”