| Multi-axis joystick and transducer means therefore HK Obermeyer, FH Obermeyer, LR Obermeyer US Patent 7,474,296, 2009 | 208 | 2009 |
| Multi-axis joystick and transducer means therefore HK Obermeyer, FH Obermeyer, L Obermeyer US Patent 8,094,121, 2012 | 135 | 2012 |
| Multi-axis input apparatus HK Obermeyer, FH Obermeyer US Patent 8,816,962, 2014 | 77 | 2014 |
| Water control gate and actuator therefore HK Obermeyer US Patent 7,114,879, 2006 | 41 | 2006 |
| Liquid level control system and method of operating the same HK Obermeyer US Patent 4,772,157, 1988 | 39 | 1988 |
| Spectrometric synthetic aperture radar HK Obermeyer US Patent 9,019,143, 2015 | 37 | 2015 |
| Hydromotive machine apparatus and method of constructing the same HK Obermeyer US Patent 4,804,855, 1989 | 36 | 1989 |
| Hydroelectric power installation and turbine generator apparatus therefor HK Obermeyer US Patent 4,755,690, 1988 | 32 | 1988 |
| Hydroelectric installation and method of constructing same HK Obermeyer, T Dum, W Sambs US Patent 6,281,597, 2001 | 29 | 2001 |
| Crest gate HK Obermeyer, CE Snow US Patent 4,780,024, 1988 | 25 | 1988 |
| Spillway crest gate system and inflatable bladder therefor HK Obermeyer, RD Eckman US Patent 5,713,699, 1998 | 23 | 1998 |
| Toughness and intergranular fracture of a simulated carburized case in EX-24 type steel HK Obermeyer, G Krauss Journal of Heat Treating 1 (3), 31-39, 1980 | 23 | 1980 |
| Connection system for reinforced composite structures HK Obermeyer US Patent 5,709,502, 1998 | 22 | 1998 |
| Spillway gate system HK Obermeyer US Patent 5,642,963, 1997 | 19 | 1997 |
| Crest gate operating system HK Obermeyer US Patent 5,092,707, 1992 | 18 | 1992 |
| Crest gate operating system HK Obermeyer US Patent 5,538,360, 1996 | 14 | 1996 |
| Hydroelectric generator having retractable runner HK Obermeyer US Patent 4,754,155, 1988 | 12 | 1988 |
| Multi-Axis Input Apparatus HK Obermeyer, FH Obermeyer US Patent App. 14/469,440, 2015 | 11 | 2015 |
| Joystick HK Obermeyer, FH Obermeyer, LR Obermeyer US Patent App. 13/347,557, 2012 | 11 | 2012 |
| Connection system for hoses, expansion joints and actuators HK Obermeyer US Patent 6,196,763, 2001 | 11 | 2001 |
