| 摘要 |
<p>PURPOSE:To aim at reducing the cost of an air pump and as well reducing the occupying space thereof, and as well to make it possible to facilitate the utilization of even used compressed air, etc., by providing the self-exciting air circuit to repeat the operation of a piston pump. CONSTITUTION:There are provided a self-exciting air-circuit 9 below a piston pump section 8 for feeding lubrication oil L under pressure, which is arranged below an oil tank 2 formed at the top end of a pump body 1. When compressed air is fed from a supply port 38 to an air chamber 14 through passages 35, 30, 32, a piston 10 is moved toward the R-side to close an oil hole 17, resulting in the pressure feed of lubrication oil in an oil chamber 15 to a bearing section M. Further, when the pressure in the air chamber 14 exceeds a predetermined value, compressed air is fed into a pilot chamber 27 through passages 30, 25 to move a spool 21 to L-side. With this arrangement passaged 30, 29, 36 are communicated with each other, and therefore, the piston 10 is returned to the L-side by a spring 11.</p> |
