Browse Prior Art Database

Publication Date: 2017-May-16
Document File: 5 page(s) / 133K

Publishing Venue

The Prior Art Database


The invention discloses systems and devices for a MV (medium voltage) switchgear door with quick opening and closing mechanism. This system includes a narrow strong and easy open/close door hinge and lock mechanism. The use of special hinges reduces the space occupied and is suitable even for narrow doors. The system provides improved holding strength by utilizing multiple lock points on all four sides of the door. The system provides special features in a low voltage power distribution panel door such as door limiter, stopper, closed door operation interlock, emergency opening mechanism, vibration/inclination resistance, anti-arcing and IP protection for medium voltage switchgear. The system is compact and can be easily installed and is suitable for marine applications.

This text was extracted from a PDF file.
This is the abbreviated version, containing approximately 52% of the total text.



The invention relates to electrical panel enclosures and in particular to door for electrical panels. A normal hinge and lock needs a minimum border width of 40~50 mm on the panel to fix the hinge, which maybe be a problem in a very narrow panel door design. Other design considerations are IP44 protection and arc resistance. Another available switchgear door lock design meets these criteria but uses screw type locks, and 5 such screw locks are normally required on a circuit breaker compartment door for arc-proofing. However, such doors take a lot of time to unlock and open.

Traditional locks have less locks points and require thick door panel and wide frame border to place are also difficult to lock on upper and lower side. To obtain thin border panel, small size hinges have to prepared, but it reduces the lock strength. To withstand explosion of arc test, more screw type lock maybe needed, it’s neither good for appearance nor the operation.


The invention discloses systems and devices for quick open-close MV switchgear door in which:

FIG. 1 illustrates system for hinge bracket mechanism and door lock support.

FIG. 2A shows device to control door lock mechanism and pin locking mechanism.

FIG. 2B shows device with door limiter and door stopper.

FIG. 3A, 3B show device with emergency opening mechanism.

FIG. 4A, 4B illustrate device providing arc resistance.

FIG. 5 shows device providing interlocking operation.


The invention discloses systems and devices for a MV (medium voltage) switchgear door with quick opening and closing mechanism. The system includes hinge and lock mechanism with elements to position the door. The door panel is installed upon the hinges with a locking mechanism. The door may be locked by a set of pins and slots. Pins are aligned in a linear manner on both sides of the door panel, 7-shaped slots are aligned on the covers of both sides as shown in FIG. 1A. The locking mechanism acts on all four sides of the door providing IP (ingress protection) and anti-arc protection as shown in FIG. 1C.

A pair of hinge brackets is attached to the switchgear box to support rotation of the door at the top and bottom for opening or closing. The door lock support rotates with the door and the door lifts along the bushing on the door providing arc resistance as shown in FIG. 1B.

FIG. 1A-1C: Device for hinge bracket mechanism and door lock support

A standard handle lock is utilized to rotate the crank as shown in FIG. 2A. The rotation drives the linkage bars to lift the door from the lock support. The slots direct the pins to move vertically, consequently moving the door. A door limiter on the hinge bracket may allow opening the door to a pre-defined maximum angle. A door stopper on the hinge bracket may keep the door at an open position as shown in FIG. 2B.

A circular...