John V Howarth

US Patent:

42771773, Jul 7, 1981

Filed:

Dec 5, 1979

Appl. No.:

6/100416

Inventors:

Tor G. Larsen - Saratoga CA
John J. Howarth - Monte Sereno CA

Assignee:

Measurex Corporation - Cupertino CA

International Classification:

G01N 2147

US Classification:

356431

Abstract:

An apparatus to measure select properties such as color, brightness or gloss, of a moving sheet, is insensitive to flutter in the sheet. The apparatus comprises a housing to one side of said sheet. A source is located in the housing; the source is capable of emitting a beam of electromagnetic radiation which is aligned to impinge the sheet. The radiation is selected such that it is capable of being absorbed and being reflected by the select properties of the sheet. A collector is also located in the housing; the collector is capable of receiving a portion of the beam reflected from the sheet. A detector capable of measuring the select properties of the sheet based upon the radiation received by the collector is also provided. The housing is held at a constant distance from the sheet by a stream of fluid from the housing directed to impinge the sheet in a direction substantially perpendicular to the sheet. A standardization member is to the other side of the sheet.

US Patent:

40121976, Mar 15, 1977

Filed:

Nov 7, 1975

Appl. No.:

5/629859

Inventors:

John J. Howarth - Monte Sereno CA

Assignee:

Measurex Corporation - Cupertino CA

International Classification:

G01N 3116
D21C 324

US Classification:

23230A

Abstract:

A titration apparatus and method therefor for determining the available alkali in a Kamyr or batch digester includes a sample vessel and a reference vessel suspended within the system itself in either the digester or associated pipelines. Carbon dioxide is used as a titrant and the end point is determined by a computer monitoring conductivity.

US Patent:

53383613, Aug 16, 1994

Filed:

Nov 4, 1991

Appl. No.:

7/787071

Inventors:

Leonard M. Anderson - San Jose CA
John J. Howarth - Scotts Valley CA

Assignee:

Measurex Corporation - Cupertino CA

International Classification:

B05C 1100

US Classification:

118689

Abstract:

The present invention relates to apparatuses and methods for measuring and controlling the amount of multiple coating materials applied to a substrate, and in particular to an apparatus and method for monitoring and regulating the amount of multiple coating materials containing different compositions applied to a substrate, such as paperboard. The coating measurement is insensitive to changes in both the amount of substrate as well as in the amount of an interfering component associated with the substrate.

US Patent:

39946029, Nov 30, 1976

Filed:

May 12, 1975

Appl. No.:

5/576543

Inventors:

John J. Howarth - San Jose CA

Assignee:

Measurex Corporation - Cupertino CA

International Classification:

G01N 2126

US Classification:

356208

Abstract:

An optical reflectance gauge which serves as a chlorination sensor for paper pulp in which a spectrum of the bulk of the material is obtained by use of displaced windows in the pulp pipe. One window has a radiation source associated with it and the other a radiation detector. The distance between such windows is determined to provide for insensitivity to small changes in consistency for measurement of chlorination. A mechanical arrangement is also provided for easier coupling of the gauge to a pulp pipe.

US Patent:

39653560, Jun 22, 1976

Filed:

May 29, 1975

Appl. No.:

5/581836

Inventors:

John J. Howarth - San Jose CA

Assignee:

Measurex Corporation - Cupertino CA

International Classification:

G01N 2126
G01J 334

US Classification:

250343

Abstract:

Measuring apparatus is used as a control element to maintain the correct ratio of chlorine to pulp in a bleach plant. Two diffusing windows are used; one to randomly radiate electromagnetic energy into the pulp and the other to receive radiation from the bulk of the pulp and reradiate it. Two bands of radiation are examined; one in the visible and the other in the infrared. Rather than using a conventional beam splitter, two detection systems, differing only in their spectral pass band, are used. Their optical axes converge in the center of the receiving window so that identical images of the receiving window can be projected on each of the detectors. The detector system allows the use of interference type filters which require sensibly parallel radiation. In addition to sensing the brightness of pulp, which is affected by the amount of chlorine, the above apparatus is useful for concurrently measuring opacity, moisture content, and basis weight of a moving sheet. A single sided moisture gauge is also provided which eliminates the effects of flutter.

US Patent:

47157151, Dec 29, 1987

Filed:

Mar 20, 1987

Appl. No.:

7/029350

Inventors:

John Howarth - Monte Sereno CA
Mark Alguard - Palo Alto CA

Assignee:

Measurex Corporation - Cupertino CA

International Classification:

G01N 2186
G01J 346

US Classification:

356402

Abstract:

A system is provided for measuring the color of a sample material, and the system includes means for illuminating the sample and a sensor to measure light from the sample. The system also includes sample backing means to receive light transmitted by the sample and reflect the light back to the sample.

US Patent:

40063585, Feb 1, 1977

Filed:

Jun 12, 1975

Appl. No.:

5/586347

Inventors:

John J. Howarth - Monte Sereno CA

Assignee:

Measurex Corporation - Cupertino CA

International Classification:

G01J 334
G01N 2134

US Classification:

250339

Abstract:

An improved method and apparatus for measuring the moisture contained by a moving sheet of web material includes a water simulating filter in a typical dual wavelength moisture gauge which provides transmission ratios. The relationship between the change of ratios of various samples of the material with different moisture content with the change of the filter ratios when various layers of moist dirt are placed in the gauge transmission path is used to provide a corrected transmission ratio from which water weight can easily be determined. The method is also applicable to polymer coatings or similar substances.

US Patent:

43198473, Mar 16, 1982

Filed:

Dec 5, 1979

Appl. No.:

6/100417

Inventors:

John J. Howarth - Monte Sereno CA

Assignee:

Measurex Corporation - Cupertino CA

International Classification:

G01N 2147

US Classification:

356431

Abstract:

An apparatus to measure select properties such as color, brightness or gloss, of a moving sheet, is insensitive to flutter in the sheet. The apparatus comprises a housing to one side of said sheet. A source is located in the housing; the source is capable of emitting a beam of electromagnetic radiation which is aligned to impinge the sheet. The radiation is selected such that it is capable of being absorbed and being reflected by the select properties of the sheet. A collector is also located in the housing; the collector is capable of receiving a portion of the beam reflected from the sheet. A detector capable of measuring the select properties of the sheet based upon the radiation received by the collector is also provided. The housing is held at a constant distance from the sheet by a stream of fluid from the housing directed to impinge the sheet in a direction substantially perpendicular to the sheet. A standardization member is to the other side of the sheet.