17,969. Goodwin, A. Dec. 23. Direct air-pressure apparatus, automatic utilizing air repeatedly; valves for pressure fluid, actuation and arrangement of.-In air-pressure apparatus for raising &c. liquids, the liquid raised by the air supplied by an air-compressor is forced into a distributing pipe system, and the action of the compressor is controlled by the pressure of the air supply so that the water-raising will continue so long as water is being drawn off from the pipe system, but will cease automatically when water is no longer drawn off. The apparatus may comprise one or two displacement chambers, and when two chambers a, a' are used, they may be superposed in the ,bore-hole &c. from which the liquid is to be removed. The air supply may be taken from one or two reservoirs c fed by one or two compressors d, and the admission and exhaust of the air to and from the chambers a, a<1> are controlled by a differential valve h connected by pipes p, to the receiver c, and by pipes t, t<1> to the chambers a, a'. The differential pistons j, j<1> operate a slide valve k to connect each chamber alternately to supply and exhaust. The exhaust air may return by a pipe u to the inlet side of the compressor d. The supply of air to the pipe s for actuating the pistons j, j<1> is controlled by a pilot valve 1, which is connected at one side to the receiver c, and at the other side to the pipes. The pilot valve may comprise two pistons 9, 10 operating a slide valve 7, which connects the pipe s alternately to admission and exhaust. The air for actuating the pistons 9, 10 is controlled by a timing-device comprising a cylinder 13 and two pistons 21, 21<a> on a rod 22 working loosely through a fixed block 23. The ports 4, 5 of the pilot valve are connected to opposite ends of the timing- device by channels 11, 12, 11<a>, 12<a>, so that when the port 4 is open to supply, compressed air enters the cylinder 13 through the port 24 and forces the piston 21 to the right. The piston 21 withdraws a small piston 21<b> from a cylinder 21<d> and allows the compressed air to pass through a channel 21<f> to the annular space 20 and force the valve 7 to the left. The spaces between the block 23 and the pistons 21, 21<a> are filled with oil and are connected by an adjustable valve for the purpose of regulating the movement of the pistons. Air is drawn into the compressor d through a valve 31 and passes through an automatic valve 32 controlled by a piston 42, which is exposed on the underside to the pressure in the receiver c. When water is no longer drawn off from the pipe system, the pressure in the receiver c rises, and the piston 42 closes the valve 32, thus taking the load off the compressor motor. A weighted lever 33 opens the valve when the pressure in the receiver falls.