Abstract The present invention is directed to a means for compensating for pressure changes in sensing devices. It is important that any sensing means immersed in a medium have internal and external pressures which are preferably the same or very close. The invention can be specifically illustrated as it applies to a cell for electrochemical analysis of a constituent in a sample. The cell comprises a body having an electrolyte reservoir, a pair of spaced electrodes positioned in the reservoir and adapted to be joined by an electrolyte in the reservoir. An opening communicates between the reservoir and the exterior of the body with a thin, flexible membrane permeable to the constituent and impermeable to electrolyte, mounted under tension over one of the electrodes, and in a position to close the opening. A passage in the body communicates between the reservoir and the exterior of the body. The improvement comprises the use of an eliptically shaped, flexible, hollow pressure compensating tube connected to the exterior end of the passage. The end of the tube farthest from the passage is closed so as to permit containment of a quantity of an electrolyte.
A CELL FOR ELECTROCHEMICAL ANALYSIS OF A CONSTITUENT IN A SAMPLE COMPRISING A BODY HAVING AN ELECTROLYTE RESERVOIR THEREIN, A PAIR OF SPACED ELECTRODES POSITIONED IN SAID RESERVOIR AND ADAPTED TO BE JOINED BY AN ELECTROLYTE IN SAID RESERVOIR, AND OPENING COMMUNICATING BETWEEN SAID RESERVOIR AND THE EXTERIOR OF SAID BODY, A THIN, FLEXIBLE POLYMERIC MEMBRANE PERMEABLE TO SAID CONSTITUENT AND IMPERMEABLE TO ELECTROLYTE, MEANS MOUNTING SAID MEMBRANE UNDER TENSION OVER ONE OF
Claim 2
Dependent Claim
73 words
A CELL FOR ELECTROCHEMICAL ANALYSIS OF A CONSTITUENT IN A SAMPLE COMPRISING A BODY HAVING AN ELECTROLYTE RESERVOIR THEREIN, A PAIR OF SPACED ELECTRODES POSITIONED IN SAID RESERVOIR AND ADAPTED TO BE JOINED BY AN ELECTROLYTE IN SAID RESERVOIR, AND OPENING COMMUNICATING BETWEEN SAID RESERVOIR AND THE EXTERIOR OF SAID BODY, A THIN, FLEXIBLE POLYMERIC MEMBRANE PERMEABLE TO SAID CONSTITUENT AND IMPERMEABLE TO ELECTROLYTE, MEANS MOUNTING SAID MEMBRANE UNDER TENSION OVER ONE OF
Claim 3
Dependent Claim
26 words
A cell according to claim 1 wherein the exterior end of said passage is fitted with a tubular means to which is connected said hollow tube.
Claim 4
Dependent Claim
23 words
A cell according to claim 2 wherein the length of said hollow tube is approximately the same as the length of said reservoir.
Claim 5
Dependent Claim
20 words
A cell according to claim 1 wherein the length of said tube is approximately the same length as the reservoir.