A key assembly configured to an electronic device is provided. The key assembly includes a switch component and a flexible button. The switch component is disposed in a case of the electronic device. The flexible button has a pressing portion, a shaft portion, at least one water-resistant portion and an actuating portion. The pressing portion is exposed from the case. The shaft portion connects the pressing portion and the actuating portion, and passes through a through hole of the case. The water-resistant portion is connected to the shaft portion and covers the through hole. The actuating portion is located in the case and aligned to the switch component. When a force is applied to the pressing portion, the pressing portion produces compressive deformation and makes the actuating portion produce expensive deformation to actuate the switch component.

A pressure switch configured to be disposed on a path, through which dust passes, to control a dust sensor according to whether a suction pressure is formed in the path, is provided. The pressure switch includes: a body part having a connection tube connected to the path, and an upper surface; first and second terminals configured to be electrically connected to the dust sensor, and at least a portion of which protrudes from the upper surface of the body part; and a flexible cap configured to engage the body part to define a space along with the upper surface of the body part. The flexible cap is deformed in response to a negative pressure being formed in the space, thereby electrically connecting the first and second terminals.

A key assembly configured to an electronic device is provided. The key assembly includes a switch component and a flexible button. The switch component is disposed in a case of the electronic device. The flexible button has a pressing portion, a shaft portion, at least one water-resistant portion and an actuating portion. The pressing portion is exposed from the case. The shaft portion connects the pressing portion and the actuating portion, and passes through a through hole of the case. The water-resistant portion is connected to the shaft portion and covers the through hole. The actuating portion is located in the case and aligned to the switch component. When a force is applied to the pressing portion, the pressing portion produces compressive deformation and makes the actuating portion produce expensive deformation to actuate the switch component.

A detector that detects an alarm and/or fault condition with respect to a pressure of a medium is provided. The detector comprises a housing comprising an access tube configured to receive a medium and a bellows fixed to the housing comprising a cavity and a first contact surface. The detector also comprises an adjustment screw positioned within the cavity of the bellows, coupled to the housing via an insulation member, and comprising a second contact surface. The detector is further configured to detect a change in pressure of the medium based on whether the first contact surface and the first contact surface are in electrical communication.

A pressure switch includes a pressure-resistant container, a contact mechanism, at least one airtight terminal, a diaphragm that is operated at first operating pressure and is restorable at restoring pressure lower than first operating pressure, a first pressing member that presses the contact mechanism due to the operation of the diaphragm and switches the contact mechanism to an open state, a pressure-receiving deformation member that is deformed and operated at second operating pressure higher than the first operating pressure, and is not restored even when the pressure decreases to atmospheric pressure after the operation at the second operating pressure, and a second pressing member that presses the contact mechanism due to the operation of the pressure-receiving deformation member and switches the contact mechanism to the open state. The first pressing member and the second pressing member are composed of an inorganic material without containing any organic material.