GB695911A - Improvements in electrode holders for ph apparatus - Google Patents

Abstract

695,911. Apparatus for pH measurement. KENT, Ltd., G. May 15, 1951, No. 11381/51. Class 37. In pH measuring apparatus, the connection between an electrode and the leads to the meter &c. is effected between rare-metal contacts in a chamber in the electrode holder, the chamber being kept dry, e.g. by a desiccating material. A glass electrode 35, Fig. 1, a resistance thermometer 41 and a reference electrode 19 shown only in the modification of Fig. 2, are mounted within a single holder. Contacts 63 on the glass and reference electrodes are located in a sealed chamber containing a desiccator 20, and make contact with spring-loaded contacts 15, so that when the glass and reference electrodes are withdrawn the contacts 15 close the apertures. The leads from the contacts 15 pass through ceramic bushes 21 soldered into an insulator plate 23 which forms part of another desiccated chamber from which the cable 6 emerges. The form shown in Fig. 1 is for dipping into the test solution while that shown in Fig. 2 is adapted for continuous observation of a solution passing through the pipes 32. Specifications 678,648 and 695,909 are referred to.