Abstract: A linear actuator system has a rotary spool valve configuration having a spool, a piston, and a cylinder. The spool and piston have return apertures so positioned, configured and angled to direct return flow towards the center of a spool central return port and spool pressure ports to direct pressurized flow into upper or lower chambers. Rotation of the spool synchronizes and aligns ports and apertures to reverse flows and effect upward and downward translation of the cylinder to vibrationally drive an implement to perform work. The positioned and angled apertures direct the fluid to a region demarcated by a total length of 1.5 times the interior diameter of the spool central return port centered about a piston shoulder. A base plug member having a bull-nose tip, baffles and cavities is disposed within the spool central return port to reduce or eliminate cavitation.

Abstract: An efficiency-enhanced resonant system is provided with a backing mass connected to a linear vibrator, a parasitic mass connected to the linear vibrator, a positioning spring, a connecting device, and external biasing springs. The linear vibrator provides vibrating force to the parasitic mass which is connected to the connecting device, grasping a working implement. The use of separate positioning spring and external biasing springs accommodates a tuned system that balances the reduction in backing mass movement, avoids backing mass resonance within the working range of frequencies, and maintains a minimized linear vibrator stroke within the optimal range for one-dimensional implements within desired frequency ranges.

Abstract: A linear actuator system has a rotary spool valve configuration having a spool, a piston, and a cylinder. The spool and piston have return apertures so positioned, configured and angled to direct return flow towards the center of a spool central return port and spool pressure ports to direct pressurized flow into upper or lower chambers. Rotation of the spool synchronizes and aligns ports and apertures to reverse flows and effect upward and downward translation of the cylinder to vibrationally drive an implement to perform work. The positioned and angled apertures direct the fluid to a region demarcated by a total length of 1.5 times the interior diameter of the spool central return port centered about a piston shoulder. A base plug member having a bull-nose tip, baffles and cavities is disposed within the spool central return port to reduce or eliminate cavitation.

Abstract: An efficiency-enhanced resonant system is provided with a backing mass connected to a linear vibrator, a parasitic mass connected to the linear vibrator, a positioning spring, a connecting device, and external biasing springs. The linear vibrator provides vibrating force to the parasitic mass which is connected to the connecting device, grasping a working implement. The use of separate positioning spring and external biasing springs accommodates a tuned system that balances the reduction in backing mass movement, avoids backing mass resonance within the working range of frequencies, and maintains a minimized linear vibrator stroke within the optimal range for one-dimensional implements within desired frequency ranges.

Abstract: A method and apparatus for reducing undesirable pressure fluctuations over predetermined pressure and frequency ranges in a working fluid system, facilitating maintenance of appropriate levels of stored energy in the fluid system. Embodiments may be employed within a fluid system to dampen pressure fluctuations over an adequately large pressure range, for example in a resonant vibratory system. In such systems, pressures vary dramatically depending on whether resonance is achieved. An apparatus comprises a pressure vessel having a self equilibrating flexible piston device. The piston separates a gas volume from a fluid volume exposed to the system flow. The piston translates within the pressure vessel to equilibrate the gas and fluid pressures. A flexible portion of the piston deflects at high frequency and adequate volume to reduce undesirable pressure fluctuations. The flexible portion translates force via its outer periphery to a ring portion which translates within the pressure vessel.