Dennis William Gilstad
Engineers at Hunters Sound, San Antonio, TX

8292260, Oct 23, 2012

Aug 16, 2011

13/210407

Dennis W. Gilstad - San Antonio TX, US

F16K 31/44

251 80, 251120, 251332, 251334, 251367

An impulse tolerant valve body is longitudinally deformable, acting through its convex valve seat interface and a concave valve seat to beneficially reduce closing energy impulse amplitude, increase impulse duration, damp induced resonance vibrations, and narrow the characteristic vibration spectrum. Elastic longitudinal valve body deformability results from elasticity in valve body construction materials and, in certain embodiments, from at least one fluid-filled internal elastic space in fluid communication with at least one internal surge chamber via at least one fluid flow restrictor. Fluid flow from elastic space to surge chamber allows substantially central longitudinal valve body compression, followed by elastic valve body rebound with reverse fluid flow. Beneficial effects are achieved through dissipation of impulse energy as heat lost through fluid flow friction and valve body hysteresis. The valve body's tendency to deform centrally causes slight rotation of its convex valve seat interface on the correspondingly-curved concave valve seat.

2014002, Jan 23, 2014

Sep 27, 2013

14/038819

Barbara C. Gilstad - San Antonio TX, US
Dennis W. Gilstad - San Antonio TX, US

F16K 17/04

251334

A tunable valve assembly reduces valve-generated vibration. One embodiment comprises a valve body and valve seat having substantially collinear longitudinal axes. A rebound characteristic frequency is associated with rebound of the elastic valve body base plate from forceful contact with the valve seat. A central cavity in the valve body encloses a spring-mass damper optionally immersed in a dilatant liquid and having a damper resonant frequency approximating a pump housing resonance. A lateral support assembly adjustably secured to the valve seat has a support resonant frequency designed in conjunction with the rebound characteristic frequency and the damper resonant frequency. Combined hysteresis heat loss associated with the above three vibration frequencies is reflected in lower closing energy impulse amplitude and damping of associated vibrations. Compliance of the elastic valve body base plate mating with the valve seat increases closing energy impulse duration and narrows the corresponding induced vibration spectrum.

8267371, Sep 18, 2012

Aug 3, 2011

13/196916

Dennis W. Gilstad - San Antonio TX, US

F16K 31/44

251 80, 251120, 251332, 251334, 251367

An impulse tolerant valve body has at least one internal variable-volume space capable of elastic longitudinal compression and rebound. Each such space is filled with incompressible fluid and has fluid communication with at least one internal surge chamber. A closing energy impulse due to valve closing causes elastic longitudinal compression of at least one variable-volume space, with consequent flow of incompressible fluid to at least one surge chamber via at least one fluid flow restrictor. During subsequent elastic rebound, incompressible fluid flows from at least one surge chamber to at least one variable-volume space, again via at least one fluid flow restrictor. A portion of valve closing impulse energy is thus redistributed as heat generated due to fluid friction losses and valve body hysteresis loss. Valve closing energy impulse amplitude is thereby reduced, impulse duration is increased, vibration spectrum is narrowed and induced resonance vibrations are damped.

8567754, Oct 29, 2013

Jul 9, 2013

13/937289

Dennis W. Gilstad - San Antonio TX, US
Barbara C. Gilstad - San Antonio TX, US

F16K 31/00

251 64, 251334, 251 80, 251318, 251 12, 251367, 13751629, 137902

Tunable valve assemblies attenuate valve-generated vibration at one or more predetermined assembly resonant frequencies which are typically altered to correspond to specific pump housing resonant frequencies. Each tunable valve assembly comprises a valve body having a peripheral groove spaced radially apart from a central reservoir. An adjustable flange may be coupled to the valve body for imposing a predetermined shear preload by partially constraining a viscoelastic element in the reservoir. One or more valve assembly resonant frequencies are thus predictably altered. Further, the associated valve-generated vibration spectrum is narrowed, and its amplitude is reduced through hysteresis loss of closing impulse energy at each predetermined assembly resonant frequency. Assembly resonant frequencies are additionally or alternatively altered through choice of viscoelastic elements and inclusions (e. g. , shear-thickening materials) in the reservoir and/or peripheral groove.

4852579, Aug 1, 1989

Apr 20, 1987

7/040597

Dennis W. Gilstad - San Antonio TX
Ronald L. Branstetter - San Antonio TX
Ralph H. Hill - San Antonio TX

Karl Storz Endoscopy GmbH and Company

A61B 502

128665

A method and apparatus for optical diagnosis and treatment of abnormal cells through the use of hormone-specific chemical markers which are preferential to genital tissues. Abnormal cells can be differentiated from normal cells by the amount of fluorescent or thermal radiation produced by the chemical marker retained in the respective cells when irradiated with electromagnetic radiation at a predetermined wavelength. Once the abnormal cells have been detected, they can be treated through the use of an optical technique based on photochemical or thermal reactions which can be controlled to destroy the abnormal cells, while leaving normal cells unharmed.

2014003, Feb 6, 2014

Oct 7, 2013

14/047046

Dennis W. Gilstad - San Antonio TX, US
Barbara C. Gilstad - San Antonio TX, US

F16K 25/00

251332

Tunable fluid end embodiments comprise a family, each family member comprising a pump housing with at least one installed tunable component chosen from: tunable valve assemblies, tunable valve seats, tunable radial arrays and/or tunable plunger seals. For example, a tunable valve assembly or tunable radial array selectively attenuates valve-generated vibration at its source, thus reducing the likelihood of fluid end failures associated with fatigue cracking and/or corrosion fatigue. Adding tunable valve seats and/or tunable plunger seals to a fluid end facilitates optimal damping and/or selective attenuation of vibration at one or more predetermined (and frequently localized) fluid end resonant frequencies. Thus, the likelihood of exciting destructive resonances in a pump's fluid end housing is further reduced. Optimized vibration attenuation and optimized fluid end damping are provided by altering resonant frequencies in each tunable component in relation to one or more fluid end resonant frequencies and/or tunable component resonant frequencies.

8276918, Oct 2, 2012

Apr 26, 2012

13/456235

Barbara C. Gilstad - San Antonio TX, US
Dennis W. Gilstad - San Antonio TX, US

F16J 15/00, F16J 15/26

277530, 277553, 277567, 277605, 277645, 277647

One or more multifunction elastomeric plunger seal rings augment a plunger packing assembly within a plunger pump packing box. Each such ring comprises a totally-enclosed circumferential tubular cavity. The cavity is filled with a dilatant liquid which transmits hydraulic pressure throughout the tubular cavity and simultaneously damps pump vibration transmitted via the packing box. Pump pressure strokes increase tubular cavity hydraulic pressure, resulting in radial ring expansion forces both inwardly toward a plunger and outwardly toward its packing box. Inward ring expansion tends to close the extrusion gap, while outward expansion force improves heat transfer from plunger to packing box. Outward expansion force also increases coupling of packing box vibration to hysteresis loss in the dilatant liquid. During reductions in both pumped fluid pressure and associated pump vibration between pressure strokes, sealing and vibration damping functions of the rings are attenuated, reducing heat generation and frictional ring wear.

8210542, Jul 3, 2012

Jul 18, 2011

13/184965

Dennis W. Gilstad - San Antonio TX, US

F16J 15/00, F16J 15/26

277530, 277553, 277567, 277605, 277645, 277647

One or more elastomeric multifunction rings augment a plunger packing assembly within a plunger pump packing box. Each such ring comprises a totally-enclosed circumferential tubular cavity filled with a fluid medium which transmits hydraulic pressure throughout the tubular cavity. Longitudinal ring compression secondary to pumped fluid pressure acts through the compliance of each ring to increase tubular cavity hydraulic pressure, resulting in radial ring expansion. Ring expansion is both inward toward a plunger and, simultaneously, outward toward its packing box. Inward expansion tends to seal the extrusion gap, while outward expansion improves heat transfer via the ring from plunger to packing box. Periodic reduction of pumped fluid pressure tends to reverse radial ring expansion. Thus, relatively more effective sealing and heat transfer functions occur as a pump's pressure stroke increases pumped fluid pressure.