PROBLEM TO BE SOLVED: To prevent the erroneous operation of a switch due to external pressure, by a simple constitution.SOLUTION: A substrate 11 is provided inside the casing 10 of an endoscope control unit. A switch hole 21 is provided in the casing 10 and is covered with a switch pressurizing part 22. At the position of the substrate 11 facing the switch pressurizing part 22, a switch body 20 is provided. On the substrate 11, pressurizing members 32 and 32 are further provided. With the elastic membranes 33 and 33 of the pressurizing members 32, and 32 the vent holes 31 and 31 of the casing 10 are covered. The elastic membranes 33 and 33 are deformed inward by being pressurized from outside. When pressure outside the casing 10 becomes larger than pressure inside the casing 10, the elastic membranes 33 and 33 are deformed to move the substrate 11. Consequently, the switch body 20 moves away from the switch pressurizing part 22, so that the switch body 20 is no longer pressed by pressurizing the switch pressurizing part 22 by external pressure.
