Method and apparatus for reading a key

• US 4,283,859 A
• Filed: 05/19/1980
• Issued: 08/18/1981
• Est. Priority Date: 05/19/1980
• Status: Expired due to Term

• Current Assignee: ILCO Unican Corp.
• Original Assignee: Maromatic Company Incorporated
• Inventors: Roland, Max G.
• Primary Examiner(s): HAROIAN, HARRY
• Application Number:
  US06/151,458
• Time in Patent Office: 456 Days
• Field of Search: 33/174 F, 33/174 P, 33/174 PA, 33/174 L, 33/175, 33/172 R, 33/172 E, 33/148 L, 33/143 L, 33/149, 29/702, 70/460, 70/394, 250/578, 250/237 R, 250/232, 250/231 R, 356/386, 356/387, 356/376, 356/381
• US Class Current: 33/539
• CPC Class Codes: E05B 19/0011 Key decoders general measuring of contours and curvatures G01B3/14, G01B5/20, G01B7/28
• CPC Class Codes: G01B 11/24 for measuring contours or curvatures
• CPC Class Codes: G01D 5/34 the beams of light being detected by photocells

Abstract

A method and apparatus for reading a key, preferably a key of the type having indentations formed in the flat sides of the key blade. Typical uses for such method and apparatus include incorporating the same in a machine for making a lock to be opened by that key or incorporation in a door lock to identify a given key and by this means a given holder of the key. Movement of reading pins which sense the key indentations are multiplied to cover or uncover groups of juxtaposed light paths to electronically record the depth of the key indentations. Plural indentations on a key can be read either sequentially or simultaneously in parallel.

Claims

1. An apparatus for reading indentations in a key, comprising:

a housing having a key opening, a rectangular key slot extending from said key opening longitudinally into the housing for receiving a key which essentially mates with the cross-section of the key slot, said key slot cross-section having at least one generally flat operative side which faces a side of the key which is generally flat and has indentations therein,

at least one flag slot extending in a plane perpendicular to the said operative side of the key slot and intersecting that side,

a reading pin in the flag slot, said reading pin being movable therein in a direction perpendicular to the said operative side of the key slot and intersecting said side, such that the pin enters the key slot across the said operative side at a point to sense conditions on the facing side of a key inserted into the key slot, limiting means to limit inward movement of the reading pin to an inward limiting position at which its end is in the key slot,

a flag member in the flag slot, said flag member extending longitudinally in a plane which is generally parallel to the said operative side of the key slot, a pivot connection pivotally connecting said flag member in the housing for movement toward and away from the plane of the operative side of the key slot, said flag member engaging the reading pin, and a spring urging the flag member in a direction to urge the pin to its inward limiting position,

a light source and a light detector positioned to provide a light path in the housing,

said flag member having a flag portion thereon located farther from the said pivot connection of the flag member than the reading pin is spaced from said pivot connection, such that movement of the flag portion is multiplied relative to corresponding movement of the reading pin, said flag portion being pivotally movable between at least an inward position corresponding to its pin sensing a certain depth of indentation on the said generally flat side of the key, and an outward position pivoted away from the inward position by the reading pin contacting a portion of the key at which the depth of the indentation is less than said certain depth,

the flag portion being positioned to move across the said light path such that in one of said inward or outward positions it blocks the light path, and in the other position it unblocks the light path,

and a clock line means for distinguishing each reading of the key by the pin from readings at successive positions along the key, as the key is moved into the key slot, past the reading pin,

whereby a plurality of different reading positions along the said generally flat side of a key can be read rapidly as the key is inserted and moved into the key slot.

2. An apparatus according to claim 1, comprising a pair of said flag slots, one on each side of the key slot, a said reading pin, a said flag member having a flag portion and a said light path being provided for each of said flag slots, whereby opposed flat sides of the key can be read simultaneously as the key is inserted into the slot.

3. An apparatus according to claim 1, including means for providing a plurality of parallel light paths associated with said flag portions, the said flag portions blocking all of said light paths in the said inward position of the pin, and said flag portions successively uncovering the light sources as the pin moves towards its outward position.

4. An apparatus according to claim 1, said light detector comprising fiber optic light paths for conveying the unblocked light to a remote reading point.

5. An apparatus according to claim 1, said light detector being a photo transistor.

6. An apparatus according to claim 4 or claim 5, said light source being an LED.

7. A method for reading the code on a key comprising the steps of:

positioning in a key slot within a housing a key which has generally flat sides with indentations on at least one side thereof corresponding to the code to be read,

urging a reading pin, mounted in the housing, into the slot, such that the tip of the reading pin moves into the key slot under a spring force to an inward limiting position,

providing at least one light path, in the housing, between a light source and a light detector,

moving a pivotally mounted elongated flag member between inward and outward limiting positions under the action of the reading pin sensing an indentation of a certain depth on the side of the key or an indentation of less than said certain depth, respectively, and arranging a portion of the flag member to block a light path in one of said positions of the reading pin and unblock it in the other of said reading pin positions,

and distinguishing successive readings of the key from each other as the key is moved into the slot, such that as the key is moved continuously into the key slot successive positions can be read and distinguished from each other.

8. A method according to claim 7, including sensing indentations on both sides of the key as the key is moved into the key slot.

9. A method according to claim 7, including providing a plurality of light paths, and wherein the flag member successively uncovers more light paths as the reading pin senses a lesser depth of indentation on the side of the key.