Pressure rate measuring apparatus

Claim 1

APPARATUS FOR MEASURING THE TIME RATE OF CHANGE OF PRESSURE COMPRISING: A FIRST PRESSURE RESISTANT CHAMBER; MEANS FOR CONNECTING THE INSIDE OF THE SAID FIRST CHAMBER TO AN EXTERNAL VARIABLE PRESSURE SOURCE; A FIRST SEALED RESILIENT BELLOWS MOUNTED WITHIN THE SAID FIRST CHAMBER, THE SAID FIRST BELLOWS BEING COMPRESSIBLE IN RESPONSE TO INCREASED PRESSURE AND EXPANDABLE IN RESPONSE TO DECREASED PRESSURE; A SECOND PRESSURE RESISTANT CHAMBER; MEANS FOR CONNECTING THE INSIDE OF THE SAID SECOND CHAMBER TO AN EXTERNAL VARIABLE PRESSURE SOURCE; A SECOND SEALED RESILIENT BELLOWS MOUNTED WITHIN THE SAID SECOND CHAMBER, THE SAID SECOND BELLOWS HAVING CHARACTERISTICS SIMILAR TO THE SAID FIRST BELLOWS; A LIQUID CONTAINED WITHIN THE SAID FIRST AND SECOND BELLOWS; AN ELONGATED CAPILLARY TUBE INTERCONNECTING THE CONTAINED LIQUID WITHIN THE SAID FIRST AND SECOND BELLOWS, THE SAID LIQUID BEING READILY TRANSFERRED BETWEEN THE TWO BELLOWS THROUGH THE SAID CAPILLARY TUBE IN RESPONSE TO DIFFERENTIAL PRESSURES WITHIN THE SAID FIRST AND SECOND PRESSURE CHAMBERS; MEANS FOR HEATING AN INTERMEDIATE PORTION OF THE SAID CAPILLARY TUBE BETWEEN THE SAID FIRST AND SECOND BELLOWS; A FIRST TEMPERATURE RESPONSIVE MEANS INTERPOSED IN THE SAID CAPILLARY TUBE BETWEEN THE SAID HEATING MEANS AND THE SAID FIRST BELLOWS; A SECOND TEMPERATURE RESPONSIVE MEANS INTERPOSED IN THE SAID CAPILLARY TUBE BETWEEN THE SAID HEATING MEANS AND THE SAID SECOND BELLOWS; MEANS FOR MEASURING THE TEMPERATURE DIFFERENTIAL BETWEEN THE SAID FIRST AND SECOND TEMPERATURE RESPONSIVE MEANS; AND MEANS FOR INDICATING THE RATE OF CHANGE OF DIFFERENTIAL PRESSURE BETWEEN THE SAID FIRST AND SECOND PRESSURE CHAMBERS AS A FUNCTION OF THE AFOREMENTIONED MEASURED DIFFERENTIAL TEMPERATURE.