James Michael Stuart

US Patent:

50447661, Sep 3, 1991

Filed:

Aug 3, 1990

Appl. No.:

7/562174

Inventors:

James G. Stuart - Mont Clare PA

Assignee:

Calspan Corporation - Buffalo NY

International Classification:

G01N 2520

US Classification:

374 43

Abstract:

The thermal time constant of fine metal wire segments, such as those used to initiate explosive reactions, is measured by passing a variable frequency source of current through the wire. The magnitudes of the sine and cosine components of the third harmonic of the voltage developed across the wire are detected and compared to each other to provide a control signal which is applied to the frequency source to change the its frequency in a direction which tends to make those components equal in magnitude. The magnitude of the control signal, when the third harmonic sine and cosine components are equal, is displayed as a function of the thermal time constant of the wire segment.

US Patent:

45194645, May 28, 1985

Filed:

Sep 23, 1983

Appl. No.:

6/535450

Inventors:

James M. Stuart - Malvern PA

Assignee:

Malvern Scale Company - Malvern PA

International Classification:

G01G 2112
G01G 2128

US Classification:

177244

Abstract:

A scale used for weighing an object or material. The scale includes a platform arranged to move upon receipt of a material thereon, frame means, a variable capacitor having a movable plate and a stationary plate, springs means which is coupled both to the frame means and to the platform, suspension means for coupling the platform to the frame means and leg support means for supporting the scale on a supporting surface. The suspension means includes an assembly having a horizontally disposed bar which is flexible in the up/down direction so as to permit ready adjustment of that assembly. The movable plate support means includes a bracket member having a thin flexible finger portion which is joined to the frame means so as to preclude distortion of the frame assembly from being transmitted to the upper capacitor plate. The lower capacitor plate is coupled to the spring means by a bracket which includes a thick portion and a thin portion. The thin portion is connected to the capacitor plate and is rigid in the up/down direction but flexible in other directions so as to permit the movable plate to expand or contract due to thermal or other effects.

US Patent:

46468595, Mar 3, 1987

Filed:

May 17, 1985

Appl. No.:

6/735503

Inventors:

James M. Stuart - Malvern PA

Assignee:

Malvern Scale Company - Malvern PA

International Classification:

G01G 2110
G01G 314
G01G 2124

US Classification:

177187

Abstract:

A scale comprising a stationary frame assembly, platform means arranged to move vertically upon receipt of some material thereon and at least one movable beam assembly, each movable beam assembly being coupled to the stationary frame assembly by a force sensing means which resists downward movement of the platform. The platform is coupled to the beam assemblies that are movable, and each movable beam assembly has a section for supporting a displacement sensing means thereon. Most preferably the displacement sensing means is an electronic sensing means adapted to move substantially horizontally for detecting movement of the movable beam assemblies that is transmitted through the platform means when the material is placed on said platform means, and said electronic sensing means produces a signal indicative of the weight of said material.

US Patent:

43724051, Feb 8, 1983

Filed:

Feb 11, 1981

Appl. No.:

6/233525

Inventors:

James M. Stuart - Malvern PA

International Classification:

G01G 1904
G01G 502
G01G 314
G01N 900

US Classification:

177 25

Abstract:

Apparatus for determining the weight, density or volume of a solid body and the weight and density of a liquid. The apparatus comprises a capacitive transducer means and compensating means therefor, as well as electronic circuitry comprising computing means including memory means, calculating means, control means and digital display means. Methods of determining the weight, density or volume of solids and the weight and density of liquids are also disclosed.

US Patent:

45248400, Jun 25, 1985

Filed:

Aug 24, 1983

Appl. No.:

6/526178

Inventors:

James M. Stuart - Malvern PA

Assignee:

Malvern Scale Company - Malvern PA

International Classification:

G01G 314

US Classification:

177210C

Abstract:

An electronic scale device used for weighing an object or material. The device includes a platform arranged to move upon receipt of a material thereon. The device further includes variable capacitance means arranged to move upon receipt of a material thereon and comprising a first plate and a second plate with one of the plates being movable. Movement of the platform means upon receipt of the material thereon causes a displacement of the movable plate relative to the other plate to produce a signal indicative of the weight of the material being weighed. The displacement of the movable plate is achieved by having the movable plate rotate about a fixed axis of rotation. Moreover, the plates are disposed so as to be non-parallel to each other over the entire operational range of movement of the movable plate, whenever the plates are not abutting each other. In one embodiment of the invention, the distances between all points on one plate and their respective corresponding points on the other plate is proportional to the respective distances each of those points is from the axis of rotation, throughout the entire operational range of movement of the movable plate.

US Patent:

45615110, Dec 31, 1985

Filed:

Nov 9, 1984

Appl. No.:

6/670659

Inventors:

James M. Stuart - Malvern PA

Assignee:

Malvern Scale Company - Malvern PA

International Classification:

G01G 300
G01G 124
G01G 314

US Classification:

177225

Abstract:

An electronic scale used for weighing an object or material. The scale includes a platform arranged to move upon receipt of a material thereon. The device further includes frame means, a variable capacitor having a first and a second plate, torsional spring means which is coupled both to the frame means and to the platform means such that movement of the platform means upon receipt of the material thereon causes the torsional means to twist about an axis without incurring non-torsional deformation. This results in one of the plates being displaced relative to the other of the plates to produce an electrical signal indicative of the weight of the material.

US Patent:

45440433, Oct 1, 1985

Filed:

Feb 28, 1984

Appl. No.:

6/584412

Inventors:

James M. Stuart - Malvern PA

Assignee:

Malvern Scale Company - Malvern PA

International Classification:

G01G 100
G01G 314
G01G 128

US Classification:

177194

Abstract:

An electronic scale used for weighing an object or material. The scale includes a weighing platform arranged to move upon receipt of a material thereon. The device further includes support means, a variable capacitor having a first and a second plate, spring means which is coupled both to the frame means and to the platform means such that movement of the platform means upon receipt of the material thereon causes the spring means to twist about an axis. The scale further includes counterbalancing means and energy absorbing connecting means to prevent error from being introduced into the weighing process, should vibrational moments be transmitted to the scale from its external environment. An alternative embodiment of the invention entails a flexure base scale, adapted to be used with counterbalancing means.