Mechanical/electronic lock and key

A lock and key system with electronic access control, comprising:

• a mechanical lock mounted in an area to be secured, with a lock cylinder, a keyway and mechanical bittings which must be matched by the bittings of a key to permit opening of the lock,
• the lock including a blocking means independent of the mechanical bittings for preventing motion which would open the lock, except when the blocking means is released,
• release means within the lock for releasing said blocking means upon power being conducted to the release means,
• contact means at the exterior of the lock for conducting power into the lock,
• key means separate from the lock, including a key blade with mechanical bittings matched to the bittings of the lock,
• the key means including a key head and lock contact means for making electrical connection with said contact means of the lock,
• the key head including a microprocessor and associated data storage containing data concerning locks to which the key is matched, and including a battery,
• the microprocessor in the key head including means for directing power via the contact means into the lock, when the key blade is inserted into the lock's keyway, means for receiving a lock ID signal from the lock via the contact means, and means for supplying power via the contact means to the release means, only upon a preselected condition being met as determined by the microprocessor means, to allow the lock to be opened, preselected condition being that the lock ID signal is indicated in said data storage as a lock authorized to be opened, and
• the blocking means and release means being contained entirely within the lock cylinder and occupying substantially no additional space within the area to be secured.

A lock with a mechanical lock configuration as well as an electronic security feature, comprising:

• a lock including a metal lock cylinder for releasing the lock, the lock cylinder comprising
• (a) a cylinder shell,
• (b) a cylinder plug rotatable within the cylinder shell and having a keyway,
• (c) a series of mechanical locking elements acting between the cylinder plug and the cylinder shell, and having a specific mechanical bitting pattern,
• (d) a blocking pin, independent of the mechanical locking elements positioned in a bore of the cylinder plug for in and out reciprocal movement in the bore and being contained essentially within the bore of the cylinder plug in a retracted condition and extending partially outwardly from the bore of the cylinder plug in a blocking condition,
• (e) a recess in the interior of the cylinder shell, positioned such that the blocking pin will engage in the recess in said blocking condition to prevent rotation of the cylinder plug,
• (f) electromagnetic release means in the cylinder plug for retracting the blocking pin to the retracted condition upon communication of electrical power to the electromagnetic release means, and means for normally holding the blocking pin in the blocking condition, when electrical power is not communicated to the electromagnetic release means, and
• (g) electrical conductive path means, including an external contact isolated from the metal of the lock cylinder, for communicating electric power from a key fitted to the lock cylinder and inserted therein, to the electromagnetic release means with the body of the cylinder acting as a ground.

A lock and key system with electronic access control, comprising:

• a mechanical lock mounted in an area to be secured, with a lock cylinder, a keyway and mechanical bittings which must be matched by the bittings of a key to permit opening of the lock,
• the lock including a blocking means independent of the mechanical bittings for preventing motion which would open the lock, except when the blocking means is released,
• release means within the lock for releasing said blocking means upon power being conducted to the release means,
• contact means at the exterior of the lock for conducting power into the lock,
• key means separate from the lock, including a key blade with mechanical bittings matched to the bittings of the lock,
• the key means including lock contact means for making electrical connection with said contact means of the lock,
• the key means including a microprocessor and associated data storage containing data concerning locks to which the key is matched, and including a battery,
• the microprocessor in the key means including means for directing power via the contact means into the lock, when the key blade is inserted into the lock's keyway, means for receiving a lock ID signal from the lock via the contact means, and means for supplying power via the contact means to the release means only upon a preselected condition being met as determined by the microprocessor means, to allow the lock to be opened, said preselected condition being that the lock ID signal is indicated in said data storage as a lock authorized to be opened, and
• the blocking means and release means being contained entirely within the lock cylinder and occupying substantially no additional space within the area to be secured.