Pressure and volume recording apparatus

Apparatus for supplying a flow of fluid under pressure to a delivery conduit, and measuring the total volume of fluid passed by the delivery conduit and also the resistance to the discharge of said flow from the delivery conduit, said apparatus comprising:

• pressure-regulated fluid supply means;
• chart recorder means comprising a first axis drive motor, and a second axis drive motor, said motors being actuable by fluid under pressure;
• a first axis conduit and a second axis conduit connecting the respective first and second drive motors to said fluid supply means;
• a first axis restrictor and a second axis restrictor in the respective first and second axis conduits between the respective motor and the fluid supply means, chart support means for supporting a chart for movement along said first axis, said first axis drive motor being adapted to move the chart and said chart support means relative to one another, marker support means for holding a marker against the chart, said second axis drive motor connected to said marker support means to move the marker and the chart relative to one another, said delivery conduit interconnected to said second axis conduit, said first axis drive motor operating unidirectionally in response to fluid delivered to it, and said second axis drive motor operating bi-directionally in response to pressure in said second axis conduit.