Issued Patents All Time
Showing 26–41 of 41 patents
| Patent # | Title | Co-Inventors | Date |
|---|---|---|---|
| 5155358 | Double wall camera housing with thermostatic cooler | — | 1992-10-13 |
| 4988987 | Keysafe system with timer/calendar features | Philip D. Barrett, Walter G. Henderson | 1991-01-29 |
| 4947163 | Electronic security system with configurable key | Walter G. Henderson, John Q. Archer, II, Gerald R. Daum, George A. Ellson, John Gray +4 more | 1990-08-07 |
| 4936894 | Pushbutton lock | John J. Risko | 1990-06-26 |
| 4916443 | Method and apparatus for compiling data relating to operation of an electronic lock system | Philip D. Barrett, Gerald R. Daum | 1990-04-10 |
| 4914732 | Electronic key with interactive graphic user interface | Walter G. Henderson, John Q. Archer, II, Gerald R. Daum, George A. Ellson, John Gray +4 more | 1990-04-03 |
| 4896246 | Electronic lock with energy conservation features | Walter G. Henderson, John Q. Archer, II, Gerald R. Daum, George A. Ellson, John Gray +4 more | 1990-01-23 |
| 4895036 | Key | John J. Risko | 1990-01-23 |
| 4887292 | Electronic lock system with improved data dissemination | Philip D. Barrett, Walter G. Henderson | 1989-12-12 |
| 4831851 | Combination/electronic lock system | — | 1989-05-23 |
| 4766746 | Electronic real estate lockbox system | Walter G. Henderson, John Q. Archer, II, Gerald R. Daum, George A. Ellson, John Gray +4 more | 1988-08-30 |
| 4727368 | Electronic real estate lockbox system | Walter G. Henderson | 1988-02-23 |
| 4626007 | Tilt bolt lock | — | 1986-12-02 |
| 4578969 | Tumbler lock having peripheral key | — | 1986-04-01 |
| 4407147 | Peripheral key tumbler lock | — | 1983-10-04 |
| 4325239 | Key safe having improved bar locking system | — | 1982-04-20 |