Electronic lock

• US 4,222,088 A
• Filed: 09/27/1978
• Issued: 09/09/1980
• Est. Priority Date: 09/27/1978
• Status: Expired due to Term

• Current Assignee: Richard H. Burton
• Original Assignee: Richard H. Burton
• Inventors: Burton, Richard H.
• Primary Examiner(s): Moose, Jr., Harry E.
• Application Number:
  US05/946,270
• Time in Patent Office: 713 Days
• Field of Search: 361/172, 340/147 MD, 340/149 R, 340/164 R, 307/10 AT
• US Class Current: 361/172
• CPC Class Codes: G07C 9/00682 actuated repeatedly

Abstract

An electronic lock having two normally open electrical contacts as input means, the closing and reopening of said contacts sequentially resulting in the entry of a binary code into a shift register. When the contents of the shift register match a predetermined but resettable programmed code, an integrating one-shot delay is triggered and a relay activated after the delay to open the lock. Momentary or continuous operation may also be programmed and reset for the lock. A power reset function is included to clear the shift register when initial power is applied or in the event of a power failure. The input means may be activated by a single three position, spring return switch or two push buttons.

Claims

1. An electronic lock comprising:

two normally open electrical contacts serving as input means representing a binary zero and one;

means to close and reopen said input contacts;

an RS flip-flop loaded by the closing of one of said contacts with the binary digit represented by said contact;

a shift register loaded with the bit from said RS flip-flop when said input contact is reopened;

said shift register capable of being loaded with a plurality of bits, all bits being shifted one position as additional bits are entered;

said shift register containing a code to open said lock when said shift register is fully loaded with bits corresponding to a predetermined code;

at least one NAND gate;

said determined code being set by jumper wires from output terminals on said shift register to said NAND gate;

an integrating one-shot delay which receives the output of said NAND gate such that when said shift register contains said predetermined code, said delay is enabled;

a relay to open said lock at the end of said delay;

a power supply to furnish electrical power to said lock.

2. The electronic lock of claim 1 further comprising:

means to enable said lock for momentary operation.

3. The electronic lock of claim 1 further comprising:

a power reset circuit to clear said shift register upon initial application of power and after a power failure.

4. The electronic lock of claim 1 wherein the means to close and reopen said input contacts comprises:

a single pole, double pole, three-position, center-off switch;

a spring to return said switch to the center-off position.

5. The electronic lock of claim 1 wherein the means to close and reopen said input contacts comprises:

two push button switches.

6. The electronic lock of claim 1 wherein said predetermined code is set and reset by changing the contact points on said jumpers on said shift register.

7. The electronic lock of claim 1 further comprising:

means to set said lock for continuous operation.

8. The electronic lock of claim 1 further comprising:

means to set said lock for momentary operation.