In an interlock system, locking of a second locking mechanism is enabled only when a first key holding part holds a first key and a control device is in a state in which a residual voltage of the control device is not discharged. Application of a power supply voltage to the control device is enabled by switching of a ground switch only when a second key holding part holds a second key. Removal of the second key from the second key holding part is enabled only when the ground switch is in the grounded position and the control device is in a grounded state. Removal of the first key from the first key holding part is enabled only when the control device is in a state in which residual voltage is discharged.

A handle (100), having: an escutcheon (106) having a recessed area (300); a lever (104) pivotally mounted toward the top end of the escutcheon and at least a portion of the lever is disposed within the recessed area when in a lever closed position (102); a first gear (310) operatively connected to a top side (312) of the lever and a portion of the first gear including gear teeth (320) extending through an opening (360) in the escutcheon; a second gear (324) mounted on a back (130) of the escutcheon and having cam teeth (322) that mesh with the gear teeth of the first gear; a cam latch (140) operatively connected to the second gear to rotate when the second gear rotates; and, a lock assembly (146) mounted to a bottom end (202) of the lever.

Examples described herein include latch mechanisms for covers. In some examples, an electronic device has an enclosure, a cover, and a latch mechanism. The enclosure may include an opening. The latch mechanism may include a rotatable arm, a spring to bias the rotatable arm to secure the cover to the enclosure, and a cam moveable between a rest position and an engaged position. In the engaged position, the cam moves the rotatable arm to release the cover.

Telecommunications enclosures (10, 110) and related methods are disclosed. In one aspect, the enclosure (10) includes a base (20), a cover (40), a lock assembly (70) for securing the base (20) to the cover (40), and a key (60) for operating the lock assembly (70). In one aspect, a lock clip (80) of the lock assembly (70) enables operation of the lock assembly (70) when the cover (40) is in the closed position. In another aspect, the lock clip (80) disables operation of the lock assembly (70) when the cover (40) is in the open position such that the lock assembly (70) is prevented from being operated out of the open position. In yet another aspect, the key (60) is prevented from being removed from the cover (40) when the key (60) operates the lock assembly (70) out of the locked position.

Button comprising a nut (1), a support (3) and a cover (5) fitted on the aforesaid support (3) defining a chamber (6) and having at least one window (51, 52) for an indicator for at least one position chosen from a first position for the button roughly corresponding to a minimum tightening torque for the nut (1) and a second position for the button corresponding to a lower tightening torque than the tightening torque for the first position, with the aforesaid indicator (30) being connected to a plate (13) by a tube element (131) which ensures that a rotation of the plate (13) is translated into a rotation of the indicator (30).

A switched-mode light-emitting diode (LED) display unit satisfying fire-fighting smoke exhaust and ventilation requirements includes an LED display unit, a mounting member, an opening-closing actuator and a pressing member. The LED display unit is mounted on the mounting member and the mounting member is mounted on a display panel by an opening-closing actuator and pressed against the display panel by a pressing member. The switched-mode LED display unit provides the pressing member that works to release the pressed mounting member after obtaining a triggering command and the opening-closing actuator that turns on the LED display unit subsequently, thereby meeting the fire smoke exhaust ventilation requirement of the internal surface or the external surface of a building.

A lockable retainer assembly adapted for retaining or releasing a panel having at least one edge by preventing or allowing movement of an edge of the panel. The lockable retainer assembly includes a rocker rotatably disposed at the edge, the rocker having a slot and is configured to protrude into the panel's path of movement when the rocker is rotatably disposed in a relaxed position. The rocker is configured to clear the panel's path of movement when the rocker is rotatably disposed in a depressed position. A lock is slidingly disposed within the slot and adapted to prevent rotation of the rocker when the lock is disposed in a relaxed position and allow rotation of the rocker when the lock is disposed in a depressed position. In the depressed position, the clears the path of movement of the panel, enabling the panel to be inserted or removed through the path.

A tamper-resistant cover apparatus includes a cover securable to the front face of a peripheral device. Such a cover permits status indicators and power buttons on the front face of the peripheral device to be visible through the cover and wherein the cover is attached to the face of the peripheral device by one or more connecting components to prevent unintended or malicious changes to the peripheral device. One or more portions of the cover can define an open area through which one or more electronic cables connect to one or more ports of the peripheral device. The open area supports the presence of electronic cables while preventing the electronic cable(s) from being removed as well as preventing unused ports from being accessed while the cover is in place.

A panel fasteners (20) is disclosed in the form of a hook and cam assembly (21) having two side walls (24) with a boss (27) through which a cam shaft (28) is journalled. The cam shaft has a socket (29) and a round cam (30). A hook (32) is frictionally mounted in camming engagement with the cam. A leaf clutch spring (33) is mounted within a spring mounting notch (36) and in frictional engagement with a substantially round cam engagement hole (34) of the hook. To position the spring into the spring mounting notch and cam engagement hole the spring is pre-compressed prior to mounting it within the spring mounting notch by forcing it through a narrowing channel positioned adjacent the cam.

A chassis door cover switch structure of an electronic device is disclosed. The electronic device includes a casing and a cover. The casing includes a latch member having a main body and a stop portion, and a plug-in space formed between the two. The cover is covered onto the casing, the locked status of both cover and casing is controlled by a control member that includes a switching button on an outer side of the cover and a switching plate on an inner side of the cover. The switching button is connected to the switching plate with a tongue portion. When the control member is moved and the tongue portion is situated outside the plug-in space, the cover and the casing are unlocked. When the tongue portion is extended into the plug-in space and stopped by the stop portion, the cover and the casing are locked.