EP1318536A1 - Differential pressure switch - Google Patents

Differential pressure switch Download PDF

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Publication number
EP1318536A1
EP1318536A1 EP02025125A EP02025125A EP1318536A1 EP 1318536 A1 EP1318536 A1 EP 1318536A1 EP 02025125 A EP02025125 A EP 02025125A EP 02025125 A EP02025125 A EP 02025125A EP 1318536 A1 EP1318536 A1 EP 1318536A1
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EP
European Patent Office
Prior art keywords
piston
differential pressure
pressure switch
switch according
tip
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.)
Withdrawn
Application number
EP02025125A
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German (de)
French (fr)
Inventor
Frank Pechhold
Arno Marto
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
BorgWarner Ludwigsburg GmbH
Original Assignee
Beru AG
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Beru AG filed Critical Beru AG
Publication of EP1318536A1 publication Critical patent/EP1318536A1/en
Withdrawn legal-status Critical Current

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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H35/00—Switches operated by change of a physical condition
    • H01H35/24—Switches operated by change of fluid pressure, by fluid pressure waves, or by change of fluid flow
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H35/00—Switches operated by change of a physical condition
    • H01H35/24—Switches operated by change of fluid pressure, by fluid pressure waves, or by change of fluid flow
    • H01H35/38—Switches operated by change of fluid pressure, by fluid pressure waves, or by change of fluid flow actuated by piston and cylinder

Definitions

  • the invention relates to a differential pressure switch according to the preamble of claim 1.
  • a disadvantage of the known differential pressure switches of the generic type is the fact that the switching operation by means of pistons and switching elements in the liquid or gaseous Medium takes place, the pressure of which is measured or whose pressure is to be used for switching.
  • the object of the invention is a differential pressure switch or sensor available, in which the actual switching or display process unaffected by Type, temperature and / or pressure of the medium takes place; nevertheless, it should be simple to build and economical to manufacture his; the penetration of moisture be prevented to the occurrence of fault currents in the Area of the switching element that hinder the switching operations can avoid.
  • the object of the invention is achieved by the differential pressure switch, in the same way as a differential pressure sensor can be formed according to the characteristic feature of Claim 1 solved. Further advantageous embodiments of the The subject of the invention result from the following Claims 2 to 7.
  • a piston 1 in a cylinder bore 2 together with a Spring 9 arranged as a return element.
  • the piston foot 1a is in communication with a medium under a pressure P 1 in space or line 8; this space can be, for example, the inlet side of a medium filter.
  • the area of the bore 2 around the tapered piston shaft 1b is connected via a line 7 to a medium under a pressure P 2 , which may be the connection to the clean side of the medium filter mentioned. If the pressure P 1 of the medium increases in comparison to the pressure P 2 , the piston 1 is set in motion in the axial direction; when the differential pressure drops, the piston 1 is moved back into its starting position by the spring 9.
  • the piston tip 1c which triggers the switching or display process, is sealed off from the medium under the pressure P 2 .
  • a funnel-shaped roller membrane 4 sealing the piston area under the piston tip 1c.
  • the tubular region 4a of the rolling membrane 4 is here preferably circular in a piston region circumferential groove stored and in this way against axial Movement secured.
  • the funnel-shaped wall 4b Roll membrane 4 is made by sealing the cylinder bore led out the end of the hole.
  • it can be in be arranged and formed to the extent that the corresponds to the maximum axial piston movement without this affect.
  • This is made possible by the fact that preferably slightly conical wall 4b Roll membrane 4 can roll in the free space. Also suitable it is when the axial extensibility of the material of the roll membrane area 4b meets these requirements, whereby then the arrangement of the roller membrane areas 4b is not movable have to be.
  • the return spring 9 rests on a shim 13 for restoring force.
  • the switching element has an upper part 11 and a lower part 10 (as a spacer) with internal sensors, contacts or similar known per se Stekergeophuse 12 and switching element 10/11 are via an O-ring 6 connected as a sealing ring; this makes control room of the Environment sealed according to the IP 67 standard.
  • differential pressure switch or Pressure sensor allows the rolling membrane 4 to move axially Piston 1, while simultaneously the switching or display area 5, i.e. the area surrounding the piston tip 1c, opposite the cylinder bore 2 and the one located therein Medium seals.

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  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Measuring Fluid Pressure (AREA)
  • Switches Operated By Changes In Physical Conditions (AREA)

Abstract

A switch element (3) is triggered by a movement of a piston held within cylindrical bore of a piston housing. A spring (9) applies a return force towards a piston head (1a). The piston tip (1c) positioned on the switching element, is sealed to the cylindrical bore by a rolling diaphragm (4) which is movable within the range of axial movement of the piston.

Description

Die Erfindung betrifft einen Differenzdruckschalter nach dem Oberbegriff des Anspruchs 1.The invention relates to a differential pressure switch according to the preamble of claim 1.

Nachteilig an den gattungsgemäßen vorbekannten Differenzdruckschaltern ist der Umstand, daß der Schaltvorgang mittels Kolben und Schaltelement in dem flüssigen oder gasförmigen Medium stattfindet, dessen Druck gemessen oder dessen Druck zum Schalten verwendet werden soll.A disadvantage of the known differential pressure switches of the generic type is the fact that the switching operation by means of pistons and switching elements in the liquid or gaseous Medium takes place, the pressure of which is measured or whose pressure is to be used for switching.

Aufgabe der Erfindung ist es, einen Differenzdruckschalter bzw.-sensor zur Verfügung zu stellen, bei dem der eigentliche Schalt- oder Anzeigevorgang unbeeinflußt von Art, Temperatur und/oder Druck des Mediums stattfindet; dennoch soll er einfach aufgebaut und wirtschaftlich herstellbar sein; hierbei soll das Eindringen von Feuchtigkeit unterbunden werden, um das Auftreten von Fehlerströmen im Bereich des Schaltelements, die die Schaltvorgänge behindern können, zu vermeiden.The object of the invention is a differential pressure switch or sensor available, in which the actual switching or display process unaffected by Type, temperature and / or pressure of the medium takes place; nevertheless, it should be simple to build and economical to manufacture his; the penetration of moisture be prevented to the occurrence of fault currents in the Area of the switching element that hinder the switching operations can avoid.

Die erfindungsgemäße Aufgabe wird durch den Differenzdruckschalter, der in gleicher Weise als Differenzdrucksensor ausgebildet sein kann, gemäß kennzeichnendem Merkmal des Anspruchs 1 gelöst. Weitere vorteilhafte Ausgestaltungen des erfindungsgemäßen Gegenstandes ergeben sich aus den nachfolgenden Ansprüchen 2 bis 7.The object of the invention is achieved by the differential pressure switch, in the same way as a differential pressure sensor can be formed according to the characteristic feature of Claim 1 solved. Further advantageous embodiments of the The subject of the invention result from the following Claims 2 to 7.

Die Erfindung wird anhand der beiliegenden Figur näher erläutert, die eine bevorzugte Ausführungsform des erfindungsgemäßen Differenzdruckschalters darstellt, wobei die Figur einen solchen Schalter im schematischen Längsschnitt wiedergibt.The invention is illustrated by the attached figure which explains a preferred embodiment of the invention Differential pressure switch represents, the Figure such a switch in a schematic longitudinal section reproduces.

Bei der dargestellten bevorzugten Ausführungsform ist ein Kolben 1 in einer Zylinderbohrung 2 zusammen mit einer Feder 9 als Rückstellelement angeordnet.In the illustrated preferred embodiment a piston 1 in a cylinder bore 2 together with a Spring 9 arranged as a return element.

Der Kolbenfuß 1a steht mit einem Medium unter einem Druck P1 in Raum oder Leitung 8 in Verbindung; bei diesem Raum kann es sich beispielsweise um die Einlasseite eines Mediumfilters handeln.The piston foot 1a is in communication with a medium under a pressure P 1 in space or line 8; this space can be, for example, the inlet side of a medium filter.

Der Bereich der Bohrung 2 um den verjüngten Kolbenschaft 1b steht über eine Leitung 7 mit einem Medium unter einem Druck P2 in Verbindung, wobei es sich hierbei um die Verbindung zur Reinseite des genannten Mediumfilters handeln kann. Steigt der Druck P1 des Mediums im Vergleich zum Druck P2, wird der Kolben 1 in axialer Richtung in Bewegung gesetzt; bei fallendem Differenzdruck wird der Kolben 1 durch die Feder 9 wieder in seine Ausgangsstellung gefahren.The area of the bore 2 around the tapered piston shaft 1b is connected via a line 7 to a medium under a pressure P 2 , which may be the connection to the clean side of the medium filter mentioned. If the pressure P 1 of the medium increases in comparison to the pressure P 2 , the piston 1 is set in motion in the axial direction; when the differential pressure drops, the piston 1 is moved back into its starting position by the spring 9.

Die Kolbenspitze 1c, die den Schalt- bzw. Anzeigevorgang auslöst, wird gegenüber dem Medium unter dem Druck P2 abgedichtet.The piston tip 1c, which triggers the switching or display process, is sealed off from the medium under the pressure P 2 .

Bei der vorliegenden Ausführungsform umschließt hierbei eine trichterförmig ausgebildete Rollmembran 4 abdichtend den Kolbenbereich unter der Kolbenspitze 1c. Hiebei ist der rohrförmige Bereich 4a der Rollmembran 4 bevorzugt in einer diesen Kolbenbereich kreisförmig umlaufenden Nut gelagert und auf diese Weise gegen axiale Verschiebung gesichert. Die trichterförmige Wand 4b der Rollmembran 4 wird unter Abdichtung der Zylinderbohrung aus dem Endbereich der Bohrung herausgeführt. Hier kann sie in dem Maße beweglich angeordnet und ausgebildet sein, das der maximalen axialen Kolbenbewegung entspricht, ohne diese zu beeinträchtigen. Dieses wird dadurch ermöglicht, daß die bevorzugt leicht konisch ausgebildete Wandung 4b der Rollmembran 4 in den Freiraum abrollen kann. Ebenso geeignet ist es, wenn die axiale Dehnbarkeit des Materials des Rollmembranbereichs 4b diesen Anforderungen entpricht, wobei dann die Anordnung der Rollmembranbereiche 4b nicht beweglich sein muß.Encloses in the present embodiment here a funnel-shaped roller membrane 4 sealing the piston area under the piston tip 1c. The tubular region 4a of the rolling membrane 4 is here preferably circular in a piston region circumferential groove stored and in this way against axial Movement secured. The funnel-shaped wall 4b Roll membrane 4 is made by sealing the cylinder bore led out the end of the hole. Here it can be in be arranged and formed to the extent that the corresponds to the maximum axial piston movement without this affect. This is made possible by the fact that preferably slightly conical wall 4b Roll membrane 4 can roll in the free space. Also suitable it is when the axial extensibility of the material of the roll membrane area 4b meets these requirements, whereby then the arrangement of the roller membrane areas 4b is not movable have to be.

Die Rückstellfeder 9 liegt an einer Einstellscheibe 13 für Rückstellkraft an. Das Schaltelement besitzt ein Oberteil 11 und ein Unterteil 10 (als Distanzscheibe) mit innenliegenden, an sich bekannten Sensoren, Kontakten o.ä. Stekergehäuse 12 und Schaltelement 10/11 sind über einen O-Ring 6 als Dichtring verbunden; hierdurch wird Schaltraum von der Umgebung gemäß Norm IP 67 abgedichtet.The return spring 9 rests on a shim 13 for restoring force. The switching element has an upper part 11 and a lower part 10 (as a spacer) with internal sensors, contacts or similar known per se Stekergehäuse 12 and switching element 10/11 are via an O-ring 6 connected as a sealing ring; this makes control room of the Environment sealed according to the IP 67 standard.

Bei dem erfindungsgemäßen Differenzdruckschalter bzw. Drucksensor läßt die Rollmembran 4 die axiale Bewegung des Kolbens 1 zu, wobei sie gleichzeitig den Schalt- bzw. Anzeigebereich 5, d.h. den die Kolbenspitze 1c umgebenden Bereich, gegenüber der Zylinderbohrung 2 und dem darin befindlichen Medium abdichtet.In the differential pressure switch or Pressure sensor allows the rolling membrane 4 to move axially Piston 1, while simultaneously the switching or display area 5, i.e. the area surrounding the piston tip 1c, opposite the cylinder bore 2 and the one located therein Medium seals.

Claims (7)

Differenzdruckschalter mit einem Kolben, der in einem Kolbengehäuse in einer Kolbenbohrung gegen die Kraft eines Rückstellelements geführt ist, wobei der Kolbenfuß mit einem Druck P1 beaufschlagt ist, während der Bohrungsraum um den verjüngten Kolbenschaft mit einem Druck P2 beaufschlagt ist, wobei durch Bewegung des Kolbens ein Schaltvorgang ausgelöst wird, dadurch gekennzeichnet, daß die Kolbenspitze (1c) im Zusammenwirken mit einem Schaltelement (3) gegenüber der Zylinderbohrung (2) durch eine im Umfang der axialen Kolbenbewegung bewegliche Rollmembran (4) abgedichtet ist.Differential pressure switch with a piston which is guided in a piston housing in a piston bore against the force of a restoring element, the piston foot being subjected to a pressure P 1 , while the bore space around the tapered piston shaft is subjected to a pressure P 2 , by movement of the Piston a switching process is triggered, characterized in that the piston tip (1c) in cooperation with a switching element (3) is sealed off from the cylinder bore (2) by a rolling diaphragm (4) which is movable in the scope of the axial piston movement. Differenzdruckschalter nach Anspruch 1, dadurch gekennzeichnet, daß die Rollmembran (4) trichterförmig ausgebildet ist, wobei der im wesentlichen rohrförmige Bereich (4a) den Kolbenschaft (1b) unterhalb der Kolbenspitze (1c) radial anliegend umschließt, während die trichterwandähnlichen Bereiche (4b) der Rollmembran (4) in dem Bohrungsbereich, der die Kolbenspitze (1c) umgibt, unter Abdichtung des Kolbenraums (2) gegenüber diesem Bohrungsbereich, geführt bzw. angeordnet sind.Differential pressure switch according to claim 1, characterized in that the rolling membrane (4) is funnel-shaped, the substantially tubular region (4a) enclosing the piston skirt (1b) below the piston tip (1c) in a radially adjacent manner, while the funnel wall-like regions (4b) Rolling membrane (4) in the bore area, which surrounds the piston tip (1c), with the piston chamber (2) sealed against this bore area, are guided or arranged. Differenzdruckschalter nach Anspruch 1 oder 2, dadurch gekennzeichnet, daß die Spitze (1c) des Kolbens (1) mit einem federnden Kontakt (3) zusammenwirkt.Differential pressure switch according to claim 1 or 2, characterized in that the tip (1c) of the piston (1) cooperates with a resilient contact (3). Differenzdruckschalter nach mindestens einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, daß die Rollmembran (4) undurchlässig für Flüssigkeiten und/oder Gase ist. Differential pressure switch according to at least one of the preceding claims, characterized in that the rolling membrane (4) is impermeable to liquids and / or gases. Differenzdruckschalter nach Anspruch 4, dadurch gekennzeichnet, daß die Rollmembran (4) aus üblichen Elastomeren besteht, die gegenüber den zu messenden Medien inert bzw. thermisch beständig sind.Differential pressure switch according to claim 4, characterized in that the rolling membrane (4) consists of conventional elastomers which are inert or thermally resistant to the media to be measured. Differenzdruckschalter nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, daß das Rückstellelement (9) mit einer Einstellscheibe (13) zur Einstellung der Rückstellkraft des Rückstellelements (9) zusammenwirkt.Differential pressure switch according to one of the preceding claims, characterized in that the restoring element (9) interacts with an adjusting disc (13) for adjusting the restoring force of the restoring element (9). Differenzdruckschalter nach einem der vorhergehenden Ansprüche, dadurch gekennzeichnet, daß zwischen Steckergehäuse (12) und Schaltelement (10/11) ein abdichtender O-Ring (6) angeordnet ist.Differential pressure switch according to one of the preceding claims, characterized in that a sealing O-ring (6) is arranged between the plug housing (12) and the switching element (10/11).
EP02025125A 2001-12-05 2002-11-08 Differential pressure switch Withdrawn EP1318536A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE10159536 2001-12-05
DE10159536A DE10159536A1 (en) 2001-12-05 2001-12-05 Differential pressure switch sensor

Publications (1)

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EP1318536A1 true EP1318536A1 (en) 2003-06-11

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EP02025125A Withdrawn EP1318536A1 (en) 2001-12-05 2002-11-08 Differential pressure switch

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US (1) US6621021B2 (en)
EP (1) EP1318536A1 (en)
DE (1) DE10159536A1 (en)

Families Citing this family (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CA2507720C (en) * 2005-05-18 2011-07-12 Kenneth Brad Hillman Rotation-proof enclosure for pressure switch housing
US7297885B2 (en) * 2005-08-29 2007-11-20 Paul Chia Lee Pressure switch
US7112753B1 (en) * 2005-08-29 2006-09-26 Paul-Chia Lee Pressure switch
US7966804B2 (en) * 2006-07-12 2011-06-28 General Electric Company Method and apparatus for testing gas turbine engines
US7891607B2 (en) * 2006-10-18 2011-02-22 The Boeing Company Pressure sensor device
CN101430987B (en) * 2007-11-06 2012-05-30 上海立新液压有限公司 Pressure relay
CA2813871C (en) 2013-04-19 2016-05-31 Canadian Heating Products Inc. Cooling system for gas fireplace

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Publication number Priority date Publication date Assignee Title
US2468768A (en) * 1949-05-03 Means to indicate the presence of
US4339955A (en) * 1980-08-29 1982-07-20 Aisin Seiki Company, Ltd. Pressure sensor
US4460812A (en) * 1981-03-11 1984-07-17 Aisin Seiki Kabushiki Kaisha Pneumatically operated switch assembly
US4654643A (en) * 1985-07-22 1987-03-31 Meisenheimer Jr Daniel T Pressure sensor-monitor and excessive pressure level indicator
EP0676785A2 (en) * 1994-04-06 1995-10-11 FILTERWERK MANN & HUMMEL GMBH Differential pressure switch

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US3486247A (en) * 1967-05-23 1969-12-30 Francis L Franet Ski boot construction
US4503301A (en) * 1983-03-24 1985-03-05 American Standard Inc. Differential fluid pressure switch
JPS612221A (en) * 1984-06-14 1986-01-08 本田技研工業株式会社 Pressure switch
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Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2468768A (en) * 1949-05-03 Means to indicate the presence of
US4339955A (en) * 1980-08-29 1982-07-20 Aisin Seiki Company, Ltd. Pressure sensor
US4460812A (en) * 1981-03-11 1984-07-17 Aisin Seiki Kabushiki Kaisha Pneumatically operated switch assembly
US4654643A (en) * 1985-07-22 1987-03-31 Meisenheimer Jr Daniel T Pressure sensor-monitor and excessive pressure level indicator
EP0676785A2 (en) * 1994-04-06 1995-10-11 FILTERWERK MANN & HUMMEL GMBH Differential pressure switch

Also Published As

Publication number Publication date
US6621021B2 (en) 2003-09-16
US20030102203A1 (en) 2003-06-05
DE10159536A1 (en) 2003-06-26

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