Gerald L Perkins

US Patent:

41451651, Mar 20, 1979

Filed:

Mar 4, 1977

Appl. No.:

5/774229

Inventors:

Gerald S. Perkins - Altadena CA
Nicholas R. Moore - Altadena CA

Assignee:

California Institute of Technology - Pasadena CA

International Classification:

F04B 1704

US Classification:

417418

Abstract:

A very high pressure pump apparatus which minimizes wear on the seals thereof and on valves connected thereto, by utilizing a very long stroke piston rod whose opposite ends are received in long cylinders. An electric motor which drives the rod, includes a rotor with a threaded aperture that receives a long threaded middle portion of the rod, so that as the rotor turns it advances the rod.

US Patent:

41881745, Feb 12, 1980

Filed:

Sep 2, 1977

Appl. No.:

5/830133

Inventors:

Gerald S. Perkins - Altadena CA

Assignee:

California Institute of Technology - Pasadena CA

International Classification:

F04B 2100
F04B 3900

US Classification:

417432

Abstract:

A valve which is resistant to wear caused by particles trapped between the valve seat and the valve member or poppet when the valve closes, including an outlet for directing washing fluid at the valve seat and/or sealing face of the poppet and means for supplying pressured fluid to the outlet at the time when the valve is closing.

US Patent:

42325625, Nov 11, 1980

Filed:

Nov 16, 1978

Appl. No.:

5/961294

Inventors:

Gerald S. Perkins - Altadena CA

Assignee:

California Institute of Technology - Pasadena CA

International Classification:

F16H 120

US Classification:

744248R

Abstract:

A linear actuator which can apply high forces is described, which includes a reciprocating rod having a threaded portion engaged by a nut that is directly coupled to the rotor of an electric motor. The nut is connected to the rotor in a manner that minimizes loading on the rotor, by the use of a coupling that transmits torque to the nut but permits it to shift axially and radially with respect to the rotor. The nut has a threaded hydrostatic bearing for engaging the threaded rod portion, with an oilcarrying groove in the nut being interrupted.

US Patent:

42527686, Feb 24, 1981

Filed:

Feb 17, 1976

Appl. No.:

5/658487

Inventors:

Gerald S. Perkins - Altadena CA
Eugene V. Pawlik - LaCanada CA
Wayne M. Phillips - La Crescenta CA

Assignee:

The United States of America as represented by the Administrator of the
National Aeronautics and Space Administration - Washington DC

International Classification:

C04B 3552

US Classification:

264332

Abstract:

An improved nozzle for use with abrasive and/or corrosive materials is formed of sintered ceramic compositions having high temperature oxidation resistance, high hardness and high abrasion and corrosion resistance. The ceramic may be a binary solid solution of a ceramic oxide and silicon nitride, and preferably a ternary solid solution of a ceramic oxide, silicon nitride and aluminum nitride. The ceramic oxide is selected from a group consisting of Al. sub. 2 O. sub. 3, Y. sub. 2 O. sub. 3 and Cr. sub. 2 O. sub. 3, or mixtures thereof. Titanium carbide particles are dispersed in the ceramic mixture before sintering. The nozzles are encased for protection from external forces while in use by a metal or plastic casing.

US Patent:

41509250, Apr 24, 1979

Filed:

Sep 2, 1977

Appl. No.:

5/830212

Inventors:

Gerald S. Perkins - Altadena CA

Assignee:

California Institute of Technology - Pasadena CA

International Classification:

F04B 1704

US Classification:

417418

Abstract:

A check valve which closes more rapidly to prevent wearing of the valve seat and of the valve member that seals thereagainst, including a solenoid or other actuator that aids the normal spring to quickly close the valve at approximately the time when downpath fluid flow would stop, the actuator then being deenergized. The control circuit that operates the actuator can include a pair of pressure sensors sensing pressure both upstream and downstream from the valve seat. Where the valve is utilized to control flow to or from a piston pump, energization of the actuator can be controlled by sensing when the pump piston reaches its extreme of travel.

US Patent:

41111842, Sep 5, 1978

Filed:

Apr 6, 1977

Appl. No.:

5/785257

Inventors:

James C. Administrator of the National Aeronautics and Space Fletcher
Gerald S. Perkins - Altadena CA

International Classification:

F24J 302

US Classification:

126270

Abstract:

A parabolic reflector is supported so that it can track the sun. The support for this reflector comprises an azimuth frame supported on two wheels and a central pivotal point which are positioned in a substantially triangular configuration. The two wheels rotate on tracks. On top of the azimuth frame, there is provided an elevation frame. The elevation frame includes curved rails which define a portion of an arc and extend vertically. The reflector rides on wheels captured within the curved rails. The wheels of the azimuth frame are driven by an azimuth actuator. The reflector structure is counterbalanced about its elevation axis by a pendulum cable system which is driven by a motor to change elevation. At the focal point of the parabolic reflector, a heat engine or receiver is mounted independently on the reflector. Suitable means are provided for moving the reflector about its two axes in order to track the sun.

US Patent:

42760038, Jun 30, 1981

Filed:

Nov 16, 1978

Appl. No.:

5/961398

Inventors:

Gerald S. Perkins - Altadena CA
Nicholas R. Moore - Altadena CA

Assignee:

California Institute of Technology - Pasadena CA

International Classification:

F04B 1700

US Classification:

417415

Abstract:

A pump system of the reciprocating piston type is described, which facilitates direct motor drive and cylinder sealing. A threaded middle potion of the piston is engaged by a nut connected to rotate with the rotor of an electric motor, in a manner that minimizes loading on the rotor by the use of a coupling that transmits torque to the nut but permits it to shift axially and radially with respect to the rotor. The nut has a threaded hydrostatic bearing for engaging the threaded piston portion, with an oil-carrying groove in the nut being interrupted. A fluid emitting seal located at the entrance to each cylinder, can serve to center the piston within the cylinder, wash the piston, and to aid in sealing. The piston can have a long stroke to diameter ratio to minimize reciprocations and wear on valves at high pressures. The voltage applied to the motor can be reversed prior to the piston reaching the end of its stroke, to permit pressure on the piston to aid in reversing the motor.

US Patent:

45863946, May 6, 1986

Filed:

Jul 30, 1982

Appl. No.:

6/403849

Inventors:

Gerald S. Perkins - Altadena CA

Assignee:

The United States of America as represented by the Administrator of the
National Aeronautics and Space Administration - Washington DC

International Classification:

F16H 118
F16H 120
F16H 2702
F16H 2902

US Classification:

744248R

Abstract:

A lead screw positioner (10) is described, which has extremely low noise, including a nut (12) lying about a lead screw (14) and means for flowing gas under pressure between the nut and screw to keep them slightly spaced. The nut forms a plenum chamber (34) which receives pressured air, and has several holes (32) leading from the chamber to the clearance space (20) between the nut and screw to apply pressured air thereto. The nut and screw are devoid of direct sealing contact, so the pressured gas flows from the holes and axially along the screw to the end of the nut, where the gas flows into the environment.