Exploded View: Mortise Locks

Oct. 15, 2003

The mortise lock, a longtime industry standard, continues to be installed into commercial, institutional and residential applications. Lock manufacturers are developing mortise locks with additional functionality and improved security to meet the needs of our ever-changing world. There are mortise locks for just about every application. In fact, there are mortise locks with modified internal components and combined with extra heavy-duty trim designed to resist forced entry.

Servicing mortise locks requires removal of the mortise cylinder, the levers (or knobs), the spindles, and the escutcheons. Once the external components have been removed, the mortise lock body is removed from the edge of the door. Here life gets interesting. Just about every lock manufacturer has its own design for every mortise lock function. Putting together a mortise lock can sometimes feel like try to re-assemble a puzzle box.

For this reason, we have included a number of mortise lock exploded views from different manufacturers. These exploded view drawing and parts charts can be helpful during re-assembly. However, when servicing a mortise lock, it is advisable to take a digital photograph of the lock, mark the locations of the components with colored markers, and/or put scratch marks on parts to identify position.

To start, we chose the Entrance Lock. The Entrance Lock is a very common mortise lock that would over time, require service. The Entrance Lock is equipped with a latch bolt and a deadbolt. From the exterior, this lock has a mortise cylinder and lever/knob. On the interior, a thumb turn and lever/knob.

The generalized function of the Entrance Lock is as follows:

When unlocked, the latch bolt can be retracted by lever/knob from either side.

When the outside is locked by rotation of thumb turn, the deadbolt is thrown. Throwing the deadbolt automatically locks outside lever/knob.

The outside lever/knob will not unlock and unlatch the mortise lock. However, the deadbolt can be retracted by rotation of thumb turn.

When locked, the key operating the mortise cylinder retracts the deadbolt and latch bolt simultaneously. Also, the interior lever/knob retracts deadbolt and latch bolt simultaneously.

We requested Entrance Lock exploded view drawings from a number of mortise lock manufacturers. Each exploded view includes a legend listing of the parts that comprise each manufacturer's mortise lock.

The exploded view drawings are: Corbin Russwin ML2051, Sargent 8291, Schlage K6452, Schlage L9453 and Yale 8747.

For more information, contact your local locksmith wholesaler or:

• Corbin Russwin, 1902 Airport Road, Monroe, NC 28110. Telephone: 800-438-1951. Fax: 800-338-0965. Website: www.corbin-russwin.com.

• Sargent Manufacturing Company, 100 Sargent Drive, P.O. Box 9725, New Haven, CT 06536. Telephone: 800-727-5477. Fax: 888-863-5054. Website: www.sargentlock.com.

• Schlage Lock Company, 111 Congressional Blvd., Suite 200, Carmel, IN 46032. Telephone: 866-422-5547. Fax: 800-366-5625. Website: www.schlagelock.com.

• Yale Commercial Locks and Hardware, 1902 Airport Road, Monroe, NC 28110. Telephone 800-438-1951. Fax 800-338-0965. Website: www.yalesecurity.com.