| 968 / | HD | HOROLOGY |
| 103 | DD | MECHANISMS FOR STABILIZING FREQUENCY (magnetic subclass 497; in striking mechanisms subclass 224; stopping and regulating of the running subclass 234; electrical and thermoelectric regulating mechanisms subclass 496) [G04B 17/00] {8} |
| 107 | | .~ Oscillators acting by spring tension [G04B 17/04] {4} |
| 108 | DD | .~.~> With oscillating blade springs (mechanical oscillations maintained by electromagnetic means, e.g., tuning forks, etc. subclass 548) [G04B 17/04B] |
| 109 | DD | .~.~> Oscillators with hairsprings, e.g., balance, etc. (electrically driven balances subclass 466; contacts actuated by a balance subclass 546) [G04B 17/06] {2} |
| 112 | DD | .~.~> Oscillators with coil springs stretched and unstretched axially [G04B 17/08] |
| 113 | DD | .~.~> Oscillators with torsion strips or springs acting in the same manner as torsion strips, e.g., weight oscillating in a horizontal plane, etc. (electrically driven torsion pendulum subclass 464) [G04B 17/10] |