Visual fluid read-out device

Claim 1

A VISUAL READ-OUT DEVICE FOR FLUID OPERATED APPARATUS, SUCH AS COMPUTERS AND THE LIKE, COMPRISING: (A) A HOUSING MEMBER HAVING AN ELONGATED TUBULAR PASSAGEWAY FORMED THEREIN; (B) A FLUID RESPONSIVE MEMBER FORMING A FLUID TIGHT FIT WITHIN SAID PASSAGEWAY AND HAVING A TRANSVERSE DIMENSION SLIGHTLY LESS THAN THAT OF THE PASSAGEWAY WITH FREEDOM TO MOVE FROM ONE END THEREOF TO THE OTHER END; AND (C) AT LEAST THREE CROSS-BORES FORMED THROUGH THE WALL OF SAID HOUSING AND INTERSECTING SAID PASSAGEWAY AT SPACED POINTS ALONG ITS LENGTH, MEANS APPLYING A RELATIVELY LOW FLUID PRESSURE TO A SELECTED ONE OF SAID CROSS-BORES AND SIMULTANEOUSLY A RELATIVELY HIGH FLUID PRESSURE TO THE REMAINDER OF SAID CROSS-BORES WHEREBY SAID FLUID RESPONSIVE MEMBER MAY BE MOVED BY PRESSURE DIFFERENCES ACROSS IT TO SAID SELECTED ONE OF SAID CROSS-BORES THEREBY TO PROVIDE A VISUAL READ-OUT BY THE POSITION OF SAID FLUID RESPONSIVE MEMBER IN SAID PASSAGEWAY.