Double cylinder lock side plate - uses hard steel with holes around keyhole opening and clearance holes in corners

摘要

A double cylinder lock for fitting inside a recess in a wooden door with its sliding bolt at the top of an upright rectangular housing, above the keyhole, as in the main patent, has an additional safety plate (13) under an escutcheon plate (6) on one side of the housing (3). This plate is of hardened steel and is between 1.5 and 2 mm thick. It is the width (b) of the housing and covers the key hole (14) region and its height (h) covers the sliding claw (T) which fits in teeth along the lower latch arm (20). It has a tapped hole (15) above and below the keyhole opening for securing the escutcheon, and has a clearance hole (16) each side of the keyhole (14) for locating pins. It also has attachment holes (17) near the corners, located in softer zones (19).