Measuring and testing – Fluid pressure gauge – With pressure and/or temperature compensation
Reexamination Certificate
2000-09-21
2003-01-28
Fuller, Benjamin R. (Department: 2855)
Measuring and testing
Fluid pressure gauge
With pressure and/or temperature compensation
Reexamination Certificate
active
06510740
ABSTRACT:
BACKGROUND OF THE INVENTION
The present invention relates to pressure transmitters used to measure fluid pressures in industrial fluid processing plants. In particular, the present invention relates to the thermal performance of such pressure transmitters.
Pressure transmitters are known to have undesired output changes when there are changes in process fluid temperature, ambient air temperature or even changes in temperature resulting from rainfall on the transmitter housings. Warm-up errors due to localized internal power dissipation are especially difficult to correct under both transient and steady state thermal conditions.
In high accuracy pressure transmitters, these output changes are controlled electronically by compensating temperature and mechanically by using two-part transmitter housings with relatively large surface areas that are joined with a threaded neck. The threaded neck separates and thermally isolates the pressure sensor and the fluid isolator from the heat generated in a circuit controlling a current output.
High accuracy circuits, sensors, and isolators are becoming more miniaturized. There is a desire for a correspondingly miniaturized, high accuracy transmitter in a single housing without the need for a threaded neck to separate the heat generated by the circuit from the pressure sensor and fluid isolator.
It is difficult, however, to manage thermal problems in such miniature housings where there is less housing surface area to dissipate heat. Problems also arise because the sensor and isolator are much closer to the heat dissipating output circuit components. A method and apparatus are needed that will provide a high accuracy, temperature compensated pressure transmitter in a single miniaturized housing.
SUMMARY OF THE INVENTION
A pressure transmitter in accordance with the present invention includes a miniature transmitter housing with an outer wall providing thermal resistance. The outer wall separates an isothermal island at a first end of the housing from a heat sink thermal island at a second end of the housing.
The isothermal island includes a fluid inlet, a pressure sensor for detecting fluid pressure from the inlet, and a temperature sensor.
The heat sink thermal island includes an electrical connector with an outer shell and a feedthrough with contacts. The heat sink island also includes a primary heat load device that is heat sunk to the outer shell. The contacts carry a current controlled by the transmitter. A major portion of that current is conducted by the primary heat load device under normal operating conditions.
The pressure transmitter controls the current to provide a temperature-compensated, high accuracy representation of the pressure.
REFERENCES:
patent: 3701280 (1972-10-01), Stroman
patent: 3968694 (1976-07-01), Clark
patent: 4120206 (1978-10-01), Rud, Jr.
patent: 4125027 (1978-11-01), Clark
patent: 4238825 (1980-12-01), Geery
patent: 4250490 (1981-02-01), Dahlke
patent: 4287501 (1981-09-01), Tominaga et al.
patent: 4414634 (1983-11-01), Louis et al.
patent: 4419898 (1983-12-01), Zanker et al.
patent: 4446730 (1984-05-01), Smith
patent: 4455875 (1984-06-01), Guimard et al.
patent: 4485673 (1984-12-01), Stern
patent: 4528855 (1985-07-01), Singh
patent: 4562744 (1986-01-01), Hall et al.
patent: 4598381 (1986-07-01), Cucci
patent: 4602344 (1986-07-01), Ferretti et al.
patent: D287827 (1987-01-01), Broden
patent: 4644797 (1987-02-01), Ichikawa et al.
patent: 4653330 (1987-03-01), Hedtke
patent: 4677841 (1987-07-01), Kennedy
patent: 4745810 (1988-05-01), Pierce et al.
patent: D296995 (1988-08-01), Lee
patent: D297314 (1988-08-01), Hedtke
patent: D297315 (1988-08-01), Pierce et al.
patent: 4783659 (1988-11-01), Frick
patent: 4791352 (1988-12-01), Frick et al.
patent: 4798089 (1989-01-01), Frick et al.
patent: 4818994 (1989-04-01), Orth et al.
patent: 4825704 (1989-05-01), Aoshima et al.
patent: 4833922 (1989-05-01), Frick et al.
patent: 4850227 (1989-07-01), Luettgen et al.
patent: 4866989 (1989-09-01), Lawless
patent: 4881412 (1989-11-01), Northedge
patent: 4930353 (1990-06-01), Kato et al.
patent: 4958938 (1990-09-01), Schwartz et al.
patent: 4970898 (1990-11-01), Walish et al.
patent: 4980675 (1990-12-01), Meisenheimer, Jr.
patent: 5000047 (1991-03-01), Kato et al.
patent: D317266 (1991-06-01), Broden et al.
patent: D317269 (1991-06-01), Selg
patent: D318432 (1991-07-01), Broden et al.
patent: 5028746 (1991-07-01), Petrich
patent: 5035140 (1991-07-01), Daniels et al.
patent: 5058437 (1991-10-01), Chaumont et al.
patent: 5060108 (1991-10-01), Baker et al.
patent: 5070732 (1991-12-01), Duncan et al.
patent: 5083091 (1992-01-01), Frick et al.
patent: 5087871 (1992-02-01), Losel
patent: 5094109 (1992-03-01), Dean et al.
patent: D329619 (1992-09-01), Cartwright
patent: 5142914 (1992-09-01), Kusakabe et al.
patent: 5157972 (1992-10-01), Broden et al.
patent: 5162725 (1992-11-01), Hodson et al.
patent: 5187474 (1993-02-01), Kielb et al.
patent: 5212645 (1993-05-01), Wildes et al.
patent: 5227782 (1993-07-01), Nelson
patent: 5236202 (1993-08-01), Krouth et al.
patent: 5245333 (1993-09-01), Anderson et al.
patent: 5248167 (1993-09-01), Petrich et al.
patent: D342456 (1993-12-01), Miller et al.
patent: 5287746 (1994-02-01), Broden
patent: 5353200 (1994-10-01), Bodin et al.
patent: 5369386 (1994-11-01), Alden et al.
patent: 5377547 (1995-01-01), Kusakabe et al.
patent: 5381355 (1995-01-01), Birangi et al.
patent: D358784 (1995-05-01), Templin, Jr. et al.
patent: 5436824 (1995-07-01), Royner et al.
patent: 5448180 (1995-09-01), Kienzler et al.
patent: 5469150 (1995-11-01), Sitte
patent: 5471885 (1995-12-01), Wagner
patent: D366000 (1996-01-01), Karas et al.
patent: D366218 (1996-01-01), Price et al.
patent: 5495768 (1996-03-01), Louwagie et al.
patent: 5498079 (1996-03-01), Price
patent: 5524333 (1996-06-01), Hogue et al.
patent: 5524492 (1996-06-01), Frick et al.
patent: 5546804 (1996-08-01), Johnson et al.
patent: 5600782 (1997-02-01), Thomson
patent: 5606513 (1997-02-01), Louwagie et al.
patent: 5650936 (1997-07-01), Loucks et al.
patent: 5656782 (1997-08-01), Powell, II et al.
patent: 5665899 (1997-09-01), Willcox
patent: 5668322 (1997-09-01), Broden
patent: 5670722 (1997-09-01), Moser et al.
patent: 5710552 (1998-01-01), McCoy et al.
patent: 5754596 (1998-05-01), Bischoff et al.
patent: 5764928 (1998-06-01), Lancott
patent: 5823228 (1998-10-01), Chou
patent: 5870695 (1999-02-01), Brown et al.
patent: 5899962 (1999-05-01), Louwagie et al.
patent: 5920016 (1999-07-01), Broden
patent: 5948988 (1999-09-01), Bodin
patent: 5954526 (1999-09-01), Smith
patent: 5955684 (1999-09-01), Gravel et al.
patent: 5973942 (1999-10-01), Nelson et al.
patent: 5988203 (1999-11-01), Hutton
patent: 6005500 (1999-12-01), Gaboury et al.
patent: 6006338 (1999-12-01), Longsdorf et al.
patent: 6038927 (2000-03-01), Karas
patent: 6050145 (2000-04-01), Olson et al.
patent: 6059254 (2000-05-01), Sundet et al.
patent: 6105437 (2000-08-01), Klug et al.
patent: 6111888 (2000-08-01), Green et al.
patent: 6115831 (2000-09-01), Hanf et al.
patent: 6123585 (2000-09-01), Hussong et al.
patent: 6140952 (2000-10-01), Gaboury
patent: 6216172 (2001-04-01), Kolblin et al.
patent: 6233532 (2001-05-01), Boudreau et al.
patent: 6285964 (2001-09-01), Babel et al.
patent: 0 268 742 (1988-06-01), None
patent: 37 41 648 (1988-07-01), None
patent: 91 09 176.4 (1991-10-01), None
patent: 197 45 244 (1997-10-01), None
patent: 299 03 260 (2000-05-01), None
patent: 0 063 685 (1982-11-01), None
patent: 0 167 941 (1985-06-01), None
patent: 0 214 801 (1987-03-01), None
patent: 0 223 300 (1987-05-01), None
patent: 0 639 039 (1995-02-01), None
patent: 0 903 651 (1999-03-01), None
patent: 2000121470 (1998-10-01), None
patent: WO 88/01417 (1988-02-01), None
patent: WO 89/02578 (1989-03-01), None
patent: WO 89/04089 (1989-05-01), None
patent: WO 90/15975 (1990-12-01), None
patent: WO 91/18266 (1991-11-01), None
patent: WO 96/34264 (1996-10-01), None
patent: WO 98/48489 (1998-10-01), None
patent: WO 00/23776 (2000-04-01), None
U.S. patent application Ser. No. 09/671,495, Behm et al., filed Sep. 27, 20
Behm Steven M.
Brekken Jeffrey C.
Krueger William B.
Orth Kelly M.
Fuller Benjamin R.
Jenkins Jermaine
Rosemount Inc.
Westman Champlin & Kelly P.A.
LandOfFree
Thermal management in a pressure transmitter does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Thermal management in a pressure transmitter, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Thermal management in a pressure transmitter will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3057016