High security cylinder lock

A cylinder lock having a normally locked position and an unlocked position, the lock when in a locked position comprising:

• a cylindrical housing including at least two apertures in a first plane defining a first set of apertures, and at least one aperture in a second plane;
• a core rotatably mounted in the housing thereby defining a shear line between the outer surface of the core and the inner surface of the housing, the core including a keyway, at least two apertures in a first plane defining a first set of apertures, and at least one aperture in a second plane which includes the keyway, the first set of apertures of the core aligning with the first set of apertures of the housing and the at least one aperture of the core in the second plane aligning with the at least one aperture of the housing in the second plane;
• each of the tumblers in said first set of tumblers being slidably disposed in a respective one of the first set of apertures of the core and housing, each of the tumblers in the first set of tumblers including two tumbler segments engaging at a first tumbler separation surface, the separation surface of at least two tumblers in the first set of tumblers having the respective separation surface disposed radially outward of the shear line such that a first segment of the first tumbler crosses the shear line, the separation surface of one of the tumblers in the first set of tumblers having its separation surface disposed at a different radial position than the separation surface of the other tumbler in the first set;
• a second tumbler slidably disposed in the apertures in the second plane of the core and housing, the second tumbler including two tumbler segments engaging at a second tumbler separation surface, the second tumbler separation surface disposed radially inward of the shear line such that a first segment of the second tumbler crosses the shear line;
• and
• the surfaces of the tumbler segments of the first set of tumblers and the tumbler segments of the second tumbler being configured such that when the lock is in the locked position, each resists movement in a radial direction upon relative displacement of the core and housing.

A cylinder lock including a keyway for receiving a key, the lock having a normally locked position and an open position when a correct key is inserted into the keyway, the cylindrical lock comprising:

• a cylindrical housing including a first aperture and a second aperture;
• a core rotatably mounted in the housing thereby defining a shear line between the outer surface of the core and the inner surface of the housing, the core including a first aperture and a second aperture;
• a first tumbler slidably disposed in the first apertures of the core and housing;
• means for positioning the first tumbler such that i) when the lock is in the locked position, the first tumbler extends across the shear line into the first apertures of the core and housing, and ii) when the lock is in the open position, the first tumbler is urged completely into the core below the shear line;
• a second tumbler slidably disposed in the second apertures of the core and housing;
• a third tumbler slidably disposed in a third aperture in the core and engaging the first tumbler at an engaging section, the third tumbler normally extending into the keyway when the lock is in the locked position, wherein the first and third tumblers include cooperating surfaces at the engaging section such that i) when the lock is in the locked position, the third tumbler holds the second tumbler across the shear line and into the second apertures of the core and housing ii) when the correct key is inserted into the keyway, the third tumbler is directed out of the keyway, the first tumbler is positioned below the shear line, and the second tumbler is urged completely into the housing above the shear line;
• the first apertures in the core and housing being disposed and the first tumbler being configured such that the first tumbler is disposed in a substantially vertical position in the plane of the keyway, and such that the first tumbler is inaccessible directly from the keyway when the lock is in the locked position;
• the first and second tumblers configured such that when the lock is in the locked position the tumblers resist radial movement upon relative movement between the core and the housing;
• and
• a key for the cylindrical lock having a top edge and sides, the top edge of the key having bits which cooperate with the second tumbler to open the lock, and one of the sides of the key having dimples which cooperate with the third tumblers to open the lock.

A cylinder lock including a keyway for receiving a key, the lock having a normally locked position and an open position when a correct key is inserted into the keyway, the cylindrical lock comprising:

• a cylindrical housing including a first aperture and a second aperture;
• a core rotatably mounted in the housing thereby defining a shear line between the outer surface of the core and the inner surface of the housing, the core including a first aperture and a second aperture;
• a first tumbler slidably disposed in the first apertures of the core and housing;
• means for positioning the first tumbler such that i) when the lock is in the locked position, the first tumbler extends across the shear line into the first apertures of the core and housing, and ii) when the lock is in the open position, the first tumbler is urged completely into the core below the shear line;
• a second tumbler slidably disposed in the second apertures of the core and housing;
• a third tumbler slidably disposed in a third aperture in the core and engaging the first tumbler at an engaging section, the third tumbler normally extending into the keyway when the lock is in the locked position, wherein the first and third tumblers include cooperating surfaces at the engaging section such that i) when the lock is in the locked position, the third tumbler holds the second tumbler across the shear line and into the second apertures of the core and housing ii) when the correct key is inserted into the keyway, the third tumbler is directed out of the keyway, the first tumbler is positioned below the shear line, and the second tumbler is urged completely into the housing above the shear line;
• the first apertures in the core and housing being disposed and the first tumbler being configured such that the first tumbler is disposed in a substantially vertical position in the plane of the keyway, and such that the first tumbler is inaccessible directly from the keyway when the lock is in the locked position;
• the first and second tumblers configured such that when the lock is in the locked position the tumblers resist radial movement upon relative movement between the core and the housing.

A cylinder lock including a keyway for receiving a key, the lock having a normally locked position and an open position when a correct key is inserted into the keyway, the cylindrical lock comprising:

• a cylindrical housing including a first aperture and a second aperture;
• a core rotatably mounted in the housing thereby defining a shear line between the outer surface of the core and the inner surface of the housing, the core including a first aperture and a second aperture;
• a first tumbler slidably disposed in the first apertures of the core and housing;
• means for positioning the first tumbler such that i) when the lock is in the locked position, the first tumbler extends across the shear line into the first apertures of the core and housing, and ii) when the lock is in the open position, the first tumbler is urged completely into the core below the shear line;
• a second tumbler slidably disposed in the second apertures of the core and housing;
• a third tumbler slidably disposed in a third aperture in the core and engaging the first tumbler at an engaging section, the third tumbler normally extending into the keyway when the lock is in the locked position, wherein the first and third tumblers include cooperating surfaces at the engaging section such that i) when the lock is in the locked position, the third tumbler holds the second tumbler across the shear line and into the second apertures of the core and housing ii) when the correct key is inserted into the keyway, the third tumbler is directed out of the keyway, the first tumbler is positioned below the shear line, and the second tumbler is urged completely into the housing above the shear line;
• the first apertures in the core and housing being disposed and the first tumbler being configured such that the first tumbler is disposed in a plane substantially parallel to the plane which includes the longitudinal axis of the second tumbler, and such that the first tumbler is inaccessible directly from the keyway when the lock is in the locked position;
• the first and second tumblers configured such that when the lock is in the locked position the tumblers resist radial movement upon relative movement between the core and the housing;
• and
• a key for the cylindrical lock having a top edge and sides, the top edge of the key having bits which cooperate with the second tumbler to open the lock, and one of the sides of the key having dimples which cooperate with the third tumblers to open the lock.

A cylinder lock including a keyway for receiving a key, the lock having a normally locked position and an open position when a correct key is inserted into the keyway, the cylindrical lock comprising:

• a cylindrical housing including a first aperture and a second aperture;
• a core rotatably mounted in the housing thereby defining a shear line between the outer surface of the core and the inner surface of the housing, the core including a first aperture and a second aperture;
• a first tumbler slidably disposed in the first apertures of the core and housing;
• means for positioning the first tumbler such that i) when the lock is in the locked position, the first tumbler extends across the shear line into the first apertures of the core and housing, and ii) when the lock is in the open position, the first tumbler is urged completely into the core below the shear line;
• a second tumbler slidably disposed in the second apertures of the core and housing;
• a third tumbler slidably disposed in a third aperture in the core and engaging the first tumbler at an engaging section, the third tumbler normally extending into the keyway when the lock is in the locked position, wherein the first and third tumblers include cooperating surfaces at the engaging section such that i) when the lock is in the locked position, the third tumbler holds the second tumbler across the shear line and into the second apertures of the core and housing ii) when the correct key is inserted into the keyway, the third tumbler is directed out of the keyway, the first tumbler is positioned below the shear line, and the second tumbler is urged completely into the housing above the shear line;
• the first apertures in the core and housing being disposed and the first tumbler being configured such that the first tumbler is disposed in a plane substantially parallel to the plane which includes the longitudinal axis of the second tumbler, and such that the first tumbler is inaccessible directly from the keyway when the lock is in the locked position;
• the first and second tumblers configured such that when the lock is in the locked position the tumblers resist radial movement upon relative movement between the core and the housing.