US20030150274A1 - Insert-molded pressure sensor with high pressure stainless steel sensing element - Google Patents
Insert-molded pressure sensor with high pressure stainless steel sensing element Download PDFInfo
- Publication number
- US20030150274A1 US20030150274A1 US10/072,231 US7223102A US2003150274A1 US 20030150274 A1 US20030150274 A1 US 20030150274A1 US 7223102 A US7223102 A US 7223102A US 2003150274 A1 US2003150274 A1 US 2003150274A1
- Authority
- US
- United States
- Prior art keywords
- pressure
- pressure vessel
- pressure port
- stainless steel
- port
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 229910001220 stainless steel Inorganic materials 0.000 title claims abstract description 22
- 239000010935 stainless steel Substances 0.000 title claims abstract description 22
- 239000002991 molded plastic Substances 0.000 abstract description 6
- 239000004033 plastic Substances 0.000 abstract description 6
- 239000000463 material Substances 0.000 abstract description 5
- 238000000465 moulding Methods 0.000 abstract description 5
- 238000007789 sealing Methods 0.000 abstract description 4
- 239000000565 sealant Substances 0.000 abstract description 2
- 230000000712 assembly Effects 0.000 description 2
- 238000000429 assembly Methods 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 230000005540 biological transmission Effects 0.000 description 1
- 239000012530 fluid Substances 0.000 description 1
- 239000000446 fuel Substances 0.000 description 1
- 238000002347 injection Methods 0.000 description 1
- 239000007924 injection Substances 0.000 description 1
- 230000010354 integration Effects 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 238000003754 machining Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 239000010705 motor oil Substances 0.000 description 1
- 239000003566 sealing material Substances 0.000 description 1
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
- G01L19/00—Details of, or accessories for, apparatus for measuring steady or quasi-steady pressure of a fluent medium insofar as such details or accessories are not special to particular types of pressure gauges
- G01L19/14—Housings
- G01L19/147—Details about the mounting of the sensor to support or covering means
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01L—MEASURING FORCE, STRESS, TORQUE, WORK, MECHANICAL POWER, MECHANICAL EFFICIENCY, OR FLUID PRESSURE
- G01L19/00—Details of, or accessories for, apparatus for measuring steady or quasi-steady pressure of a fluent medium insofar as such details or accessories are not special to particular types of pressure gauges
- G01L19/0007—Fluidic connecting means
- G01L19/0038—Fluidic connecting means being part of the housing
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F02—COMBUSTION ENGINES; HOT-GAS OR COMBUSTION-PRODUCT ENGINE PLANTS
- F02M—SUPPLYING COMBUSTION ENGINES IN GENERAL WITH COMBUSTIBLE MIXTURES OR CONSTITUENTS THEREOF
- F02M2200/00—Details of fuel-injection apparatus, not otherwise provided for
- F02M2200/24—Fuel-injection apparatus with sensors
- F02M2200/247—Pressure sensors
Definitions
- This invention relates to a high pressure sensor, and more particularly to a low cost stainless steel pressure sensor assembly that is integrated into a molded plastic component.
- the present invention provides an improved pressure sensor assembly incorporating a stainless steel pressure sensing element, wherein the pressure sensing element is welded to a stainless steel pressure port that is insert-molded into a molded plastic pressure vessel. Sealing between the pressure port and the pressure vessel is enhanced by a O-ring seated in a groove on the outer periphery of the pressure port, or by a sealant applied to the periphery of the pressure port prior to the insert molding operation.
- the pressure port is insert-molded with the pressure vessel so as to expose an axial end of the pressure port having a stepped annular surface, and the pressure sensor element is welded to the exposed end of the pressure port.
- the plastic material of the pressure vessel extends into a central axial bore of the pressure port to minimize leakage by maximizing a potential leakage path for the medium contained by the pressure vessel, and over a shoulder of the pressure port to secure the pressure port in the body of the pressure vessel.
- the single drawing figure is a cross-sectional view of a stainless steel pressure sensor integrated with a molded plastic pressure vessel according to this invention.
- the reference numeral 10 designates the wall of a plastic pressure vessel containing a high pressure liquid or gaseous medium
- the reference numeral 12 generally designates a pressure sensor assembly integrated into the pressure vessel wall 10 by an insert molding operation.
- the pressure sensor assembly 12 includes a stainless steel pressure sensing element 14 , a stainless steel pressure port 16 , a sealing device such as an O-ring 18 , and a terminal cover 20 which is only partially illustrated in the drawing figure.
- the stainless steel pressure sensing element 14 includes a cylindrical diaphragm 14 a with a central mass 14 b , and an annular side-wall 14 c depending from the rim of diaphragm 14 a .
- Stress sensitive elements are formed on the exposed surface of diaphragm 14 a between the central mass 14 b and the side-wall 14 c , and connected in a bridge arrangement to detect stress due to a pressure difference across the diaphragm 14 a .
- these elements are coupled (by wire bonding, for example) to an integrated circuit chip (not shown) which may be mounted on the outer surface of diaphragm 14 a opposite central mass 14 b .
- the integrated circuit detects and amplifies resistance variations due to the sensed pressure, and provides an electrical signal output which is coupled to metallic terminals (not shown) which may be integrated into the cover 20 .
- the stainless steel pressure port 16 is cylindrical cross-section, with a central axial bore 16 a .
- the outer periphery of the pressure port 16 is stepped as shown to define upper and lower portions 16 b , 16 c , the lower portion 16 b having a larger outside diameter than the upper portion 16 c .
- a circumferential groove 16 d formed on the outer periphery of the lower portion 16 b receives the O-ring 18
- a step 16 e formed on the outer periphery of the upper portion 16 c accommodates the annular side-wall 14 c of the sensor element 14 .
- the stainless steel pressure port 16 is secured in the mold used to form the pressure vessel wall 10 such that plastic material injected into the mold surrounds and encases the pressure port 16 , leaving part of the exterior periphery of upper portion 16 c exposed, as shown.
- the plastic material extends into the axial bore 16 a as indicated by the reference numeral 10 a , around the O-ring 18 and the exterior periphery of the lower portion 16 b as indicated by the reference numeral 10 b , and around part of the exterior periphery of the upper portion 16 c as indicated by the reference numeral 10 c .
- the injection pressure compresses the O-ring 18 into the circumferential groove 16 d to maximize its sealing capability.
- the O-ring may be replaced (or supplemented) by a sealing material applied to the periphery of pressure port 16 prior to the molding operation, if so desired.
- the insert-molded pressure sensor assembly of the present invention contributes to reduced cost by minimizing the usage of stainless steel and integrating the pressure port with a plastic pressure vessel containing the medium to be measured. While the invention has been described in reference to the illustrated embodiment, it is expected that various modifications in addition to those mentioned above will occur to those skilled in the art. Accordingly, it will be understood that sensor assemblies incorporating such modifications may fall within the scope of this invention, which is defined by the appended claims.
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- Measuring Fluid Pressure (AREA)
Abstract
An improved pressure sensor assembly incorporates a stainless steel pressure sensing element that is welded to a stainless steel pressure port insert-molded into a molded plastic pressure vessel. Sealing between the pressure port and the pressure vessel is enhanced by a O-ring seated in a groove on the outer periphery of the pressure port, or by a sealant applied to the periphery of the pressure port prior to the insert molding operation. The pressure port is insert-molded with the pressure vessel so as to expose an axial end of the pressure port having a stepped annular surface, and the pressure sensor element is welded to the exposed end of the pressure port. The plastic material of the pressure vessel extends into a central axial bore of the pressure port to minimize leakage by maximizing a potential leakage path for the medium contained by the pressure vessel, and over a shoulder of the pressure port to secure the pressure port in the body of the pressure vessel.
Description
- This invention relates to a high pressure sensor, and more particularly to a low cost stainless steel pressure sensor assembly that is integrated into a molded plastic component.
- Motor vehicle controls frequently require measurement of certain pressure parameters such as engine oil pressure, fuel pressure, transmission fluid pressure or brake pressure. For reliability and durability, such applications usually require the use of a stainless steel pressure sensor element. In a typical application, the sensor element is welded to stainless steel a pressure port that is attached to the pressure vessel by a threaded fitting, for example. Due to the high cost of stainless steel relative to other materials, and the difficulty of machining stainless steel, various pressure port configurations have been developed for minimizing the required amount of stainless steel. See, for example, the U.S. Pat. Nos. 5,939,637 and 6,050,147, both of which are assigned to the assignee of the present invention. However, there is a growing interest in integrating a pressure sensor with the pressure vessel instead of attaching the pressure sensor to the pressure vessel by a threaded fitting, particularly in the case of molded plastic pressure vessels. Accordingly, what is needed is a pressure sensor assembly that minimizes the usage of stainless steel while being amenable to integration with molded plastic assemblies.
- The present invention provides an improved pressure sensor assembly incorporating a stainless steel pressure sensing element, wherein the pressure sensing element is welded to a stainless steel pressure port that is insert-molded into a molded plastic pressure vessel. Sealing between the pressure port and the pressure vessel is enhanced by a O-ring seated in a groove on the outer periphery of the pressure port, or by a sealant applied to the periphery of the pressure port prior to the insert molding operation. According to the invention, the pressure port is insert-molded with the pressure vessel so as to expose an axial end of the pressure port having a stepped annular surface, and the pressure sensor element is welded to the exposed end of the pressure port. In a preferred embodiment, the plastic material of the pressure vessel extends into a central axial bore of the pressure port to minimize leakage by maximizing a potential leakage path for the medium contained by the pressure vessel, and over a shoulder of the pressure port to secure the pressure port in the body of the pressure vessel.
- The single drawing figure is a cross-sectional view of a stainless steel pressure sensor integrated with a molded plastic pressure vessel according to this invention.
- Referring to the single drawing figure, the
reference numeral 10 designates the wall of a plastic pressure vessel containing a high pressure liquid or gaseous medium, and thereference numeral 12 generally designates a pressure sensor assembly integrated into thepressure vessel wall 10 by an insert molding operation. In addition to thepressure vessel wall 10, thepressure sensor assembly 12 includes a stainless steelpressure sensing element 14, a stainlesssteel pressure port 16, a sealing device such as an O-ring 18, and aterminal cover 20 which is only partially illustrated in the drawing figure. - The stainless steel
pressure sensing element 14 includes acylindrical diaphragm 14 a with acentral mass 14 b, and an annular side-wall 14 c depending from the rim ofdiaphragm 14 a. Stress sensitive elements are formed on the exposed surface ofdiaphragm 14 a between thecentral mass 14 b and the side-wall 14 c, and connected in a bridge arrangement to detect stress due to a pressure difference across thediaphragm 14 a. Typically, these elements are coupled (by wire bonding, for example) to an integrated circuit chip (not shown) which may be mounted on the outer surface ofdiaphragm 14 a oppositecentral mass 14 b. The integrated circuit detects and amplifies resistance variations due to the sensed pressure, and provides an electrical signal output which is coupled to metallic terminals (not shown) which may be integrated into thecover 20. - The stainless
steel pressure port 16 is cylindrical cross-section, with a centralaxial bore 16 a. The outer periphery of thepressure port 16 is stepped as shown to define upper andlower portions lower portion 16 b having a larger outside diameter than theupper portion 16 c. Acircumferential groove 16 d formed on the outer periphery of thelower portion 16 b receives the O-ring 18, and astep 16 e formed on the outer periphery of theupper portion 16 c accommodates the annular side-wall 14 c of thesensor element 14. - During manufacture of the pressure vessel, the stainless
steel pressure port 16 is secured in the mold used to form thepressure vessel wall 10 such that plastic material injected into the mold surrounds and encases thepressure port 16, leaving part of the exterior periphery ofupper portion 16 c exposed, as shown. In particular, the plastic material extends into theaxial bore 16 a as indicated by thereference numeral 10 a, around the O-ring 18 and the exterior periphery of thelower portion 16 b as indicated by thereference numeral 10 b, and around part of the exterior periphery of theupper portion 16 c as indicated by thereference numeral 10 c. This minimizes leakage by maximizing a potential leakage path for the medium contained by the pressure vessel, and secures thepressure port 16 in thepressure vessel wall 10. Additionally, the injection pressure compresses the O-ring 18 into thecircumferential groove 16 d to maximize its sealing capability. As indicated above, the O-ring may be replaced (or supplemented) by a sealing material applied to the periphery ofpressure port 16 prior to the molding operation, if so desired. When the molding operation is completed, the pressure vessel and integratedpressure port 16 are removed from the mold, and thepressure sensing element 14 is seated on thestep 16 e and welded in place as shown. In usage, the medium contained by the pressure vessel is applied directly to the inboard surface of thesensor diaphragm 14 a via thepressure wall portion 10 a. - In summary, the insert-molded pressure sensor assembly of the present invention contributes to reduced cost by minimizing the usage of stainless steel and integrating the pressure port with a plastic pressure vessel containing the medium to be measured. While the invention has been described in reference to the illustrated embodiment, it is expected that various modifications in addition to those mentioned above will occur to those skilled in the art. Accordingly, it will be understood that sensor assemblies incorporating such modifications may fall within the scope of this invention, which is defined by the appended claims.
Claims (5)
1. An integrated pressure vessel and pressure sensor assembly comprising:
a pressure vessel including a molded pressure vessel wall having an opening formed therein;
a stainless steel pressure port partially encased in said pressure vessel wall, and having a central axial bore that is aligned with the opening in said pressure vessel wall;
a compressible seal element disposed between the encased part of said pressure port and the pressure vessel wall; and
a stainless steel pressure sensor element welded to an axial end of said stainless steel pressure port that protrudes from said pressure vessel wall outside said pressure vessel, placing an inboard surface of said pressure sensor element in direct contact with a medium contained by said pressure vessel.
2. The integrated pressure vessel and pressure sensor assembly of claim 1 , wherein said the encased part of said pressure port includes a circumferential groove, and said compressible seal element is an O-ring disposed in said circumferential groove.
3. The integrated pressure vessel and pressure sensor assembly of claim 1 , wherein an inner periphery of said central axial bore is encased by said pressure vessel wall.
4. The integrated pressure vessel and pressure sensor assembly of claim 1 , wherein said pressure port is insert-molded in said pressure vessel wall.
5. The integrated pressure vessel and pressure sensor assembly of claim 1 , wherein said pressure port includes a first portion that is completely encased by said pressure vessel wall and a second portion that is only partially encased by said pressure vessel wall, said second portion having a width dimension that is smaller than a width dimension of said first portion.
Priority Applications (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US10/072,231 US6604429B1 (en) | 2002-02-11 | 2002-02-11 | Insert-molded pressure sensor with high pressure stainless steel sensing element |
EP03075190A EP1335195B1 (en) | 2002-02-11 | 2003-01-21 | Insert-molded assembly of a pressure sensor with a pressure vessel |
DE60301073T DE60301073T2 (en) | 2002-02-11 | 2003-01-21 | Insert sprayed unit of a pressure transducer with a pressure vessel |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US10/072,231 US6604429B1 (en) | 2002-02-11 | 2002-02-11 | Insert-molded pressure sensor with high pressure stainless steel sensing element |
Publications (2)
Publication Number | Publication Date |
---|---|
US6604429B1 US6604429B1 (en) | 2003-08-12 |
US20030150274A1 true US20030150274A1 (en) | 2003-08-14 |
Family
ID=27610556
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US10/072,231 Expired - Fee Related US6604429B1 (en) | 2002-02-11 | 2002-02-11 | Insert-molded pressure sensor with high pressure stainless steel sensing element |
Country Status (3)
Country | Link |
---|---|
US (1) | US6604429B1 (en) |
EP (1) | EP1335195B1 (en) |
DE (1) | DE60301073T2 (en) |
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2015068726A (en) * | 2013-09-30 | 2015-04-13 | 株式会社デンソー | Pressure sensor |
US20150276787A1 (en) * | 2014-03-28 | 2015-10-01 | Honeywell International Inc. | Co-location of high-maintenance air data system components into one lru |
JP2017102011A (en) * | 2015-12-01 | 2017-06-08 | 長野計器株式会社 | Physical quantity measurement device |
JP2017120219A (en) * | 2015-12-28 | 2017-07-06 | 日立オートモティブシステムズ株式会社 | Pressure detector |
Families Citing this family (15)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US7212096B2 (en) * | 2003-01-09 | 2007-05-01 | Kulite Semiconductor Products, Inc. | Pressure sensor header having an integrated isolation diaphragm |
US7369032B2 (en) * | 2003-01-09 | 2008-05-06 | Kulite Semiconductor Products, Inc. | Method of joining a pressure sensor header with an associated transducer element |
US20040135666A1 (en) * | 2003-01-09 | 2004-07-15 | Kurtz Anthony D. | Pressure sensor header having an integrated isolation diaphragm |
US6817226B2 (en) * | 2003-03-18 | 2004-11-16 | Delphi Technologies, Inc. | Sensing assembly and method of making same |
US6805016B1 (en) | 2003-03-24 | 2004-10-19 | Delphi Technologies, Inc. | Sensing assembly removably securable to a bearing mechanism |
JP2006226756A (en) * | 2005-02-16 | 2006-08-31 | Denso Corp | Pressure sensor |
US7373830B2 (en) * | 2006-04-25 | 2008-05-20 | Honeywell International Inc. | Metal/thermo plastic port design for media isolated pressure transducers |
US7911315B2 (en) * | 2006-07-28 | 2011-03-22 | Honeywell International Inc. | Miniature pressure sensor assembly for catheter |
DE102011102768B4 (en) | 2011-05-28 | 2019-10-17 | Audi Ag | Pressure storage device for a fuel supply device |
US9804002B2 (en) * | 2013-09-04 | 2017-10-31 | Cameron International Corporation | Integral sensor |
DE102014222806A1 (en) * | 2014-11-07 | 2016-05-12 | Robert Bosch Gmbh | fuel injector |
DE102014223659A1 (en) * | 2014-11-20 | 2016-05-25 | Robert Bosch Gmbh | fuel injector |
JP6163148B2 (en) * | 2014-11-20 | 2017-07-12 | 長野計器株式会社 | Pressure sensor |
US10209154B2 (en) * | 2015-03-30 | 2019-02-19 | Rosemount Inc. | In-line process fluid pressure transmitter for high pressure applications |
JP2018163074A (en) * | 2017-03-27 | 2018-10-18 | 日本電産トーソク株式会社 | Hydraulic sensor mounting structure |
Family Cites Families (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5703296A (en) * | 1995-06-27 | 1997-12-30 | Delco Electronics Corp. | Pressure sensor having reduced hysteresis and enhanced electrical performance at low pressures |
US5802912A (en) * | 1996-01-25 | 1998-09-08 | Delco Electronics Corporation | Electrical terminal apparatus |
WO1999028718A1 (en) * | 1997-12-02 | 1999-06-10 | Fluoroware, Inc. | Fluid monitoring device |
US5939637A (en) * | 1997-12-05 | 1999-08-17 | Delco Electronics Corp. | Three-piece pressure sensor with high pressure stainless steel sensor element |
US6050147A (en) * | 1997-12-05 | 2000-04-18 | Delco Electronics Corp. | Pressure sensor assembly |
US6176138B1 (en) * | 1998-07-15 | 2001-01-23 | Saba Instruments, Inc. | Electronic pressure sensor |
EP0984258B1 (en) * | 1998-09-05 | 2002-01-02 | Mannesmann VDO Aktiengesellschaft | Pressure sensor mounting means |
-
2002
- 2002-02-11 US US10/072,231 patent/US6604429B1/en not_active Expired - Fee Related
-
2003
- 2003-01-21 DE DE60301073T patent/DE60301073T2/en not_active Expired - Lifetime
- 2003-01-21 EP EP03075190A patent/EP1335195B1/en not_active Expired - Lifetime
Cited By (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2015068726A (en) * | 2013-09-30 | 2015-04-13 | 株式会社デンソー | Pressure sensor |
US20150276787A1 (en) * | 2014-03-28 | 2015-10-01 | Honeywell International Inc. | Co-location of high-maintenance air data system components into one lru |
US10401376B2 (en) * | 2014-03-28 | 2019-09-03 | Honeywell International Inc. | Co-location of high-maintenance air data system components into one LRU |
JP2017102011A (en) * | 2015-12-01 | 2017-06-08 | 長野計器株式会社 | Physical quantity measurement device |
US10145749B2 (en) | 2015-12-01 | 2018-12-04 | Nagano Keiki Co., Ltd. | Physical quantity measuring device including a sensor module and a joint for locking the sensor module |
JP2017120219A (en) * | 2015-12-28 | 2017-07-06 | 日立オートモティブシステムズ株式会社 | Pressure detector |
Also Published As
Publication number | Publication date |
---|---|
DE60301073T2 (en) | 2006-04-13 |
EP1335195A1 (en) | 2003-08-13 |
EP1335195B1 (en) | 2005-07-27 |
US6604429B1 (en) | 2003-08-12 |
DE60301073D1 (en) | 2005-09-01 |
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Legal Events
Date | Code | Title | Description |
---|---|---|---|
AS | Assignment |
Owner name: DELPHI TECHNOLOGIES, INC., MICHIGAN Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNOR:PITZER, PAUL J.;REEL/FRAME:012599/0185 Effective date: 20011207 |
|
FPAY | Fee payment |
Year of fee payment: 4 |
|
REMI | Maintenance fee reminder mailed | ||
LAPS | Lapse for failure to pay maintenance fees | ||
STCH | Information on status: patent discontinuation |
Free format text: PATENT EXPIRED DUE TO NONPAYMENT OF MAINTENANCE FEES UNDER 37 CFR 1.362 |
|
FP | Lapsed due to failure to pay maintenance fee |
Effective date: 20110812 |