ELECTRODE HOLDER

摘要

In an electrode holder (1), including: an electrode shaft (3) having one end as a terminal portion (3a) and the other end as a detection, electrode portion (3b) ; and a container mounting portion (6) having a through-hole (4) and formed of metal, for holding the electrode shaft (3) in the through-hole (4) through an intermediation of an insulator (5) formed of a synthetic resin, the electrode shaft (3) passes through a hole portion (7) of a metal container (2) and is mounted to the metal container (2) by the container mounting portion (6) in a state where the electrode shaft (3) is electrically insulated from the metal container (2) by the insulator (5). The container mounting portion (6) is provided with, in the through-hole (4) thereof, a seat portion (8) having a substantially ring shape and protruding from an inner peripheral wall of the container mounting portion (6) formed by the through-hole (4). The electrode shaft (3) is provided with, on an outer periphery thereof, an engagement protruding portion (13, 14) on at least one of an inner side and an outer side in an axial direction of the electrode shaft (3) with respect to the seat portion (8), the engagement protruding portion (13, 14) being spaced apart from the seat portion (8) and having a larger diameter than a hole diameter of the seat portion (8). Therefore, when, for example, the inside of the metal container (2) is in a high-temperature state, the insulator (5) is destroyed, and the electrode shaft (3) held by the container mounting portion (6) is about to burst out of or into the metal container (2) from the container mounting portion (6), the engagement protruding portion (13, 14) provided to the outer periphery of the electrode shaft (3) engages with the seat portion (8) provided in the through-hole (4) of the container mounting portion (6), thereby making it possible to prevent the electrode shaft (3) from bursting out of or into the metal container (2). Further, a gap generated between the electrode shaft (3) and the container mounting portion (6) due to the destruction of the insulator (5) is closed by engagement of the engagement protruding portion (13, 14) provided on the outer periphery of the electrode shaft (3) with respect to the seat portion (8). Thus, it is possible to suppress a leakage of a liquid in the metal container (2) as much as possible even when the insulator (5) is destroyed.