EP1363305A1 - Druckschalter - Google Patents

Druckschalter Download PDF

Info

Publication number
EP1363305A1
EP1363305A1 EP02425297A EP02425297A EP1363305A1 EP 1363305 A1 EP1363305 A1 EP 1363305A1 EP 02425297 A EP02425297 A EP 02425297A EP 02425297 A EP02425297 A EP 02425297A EP 1363305 A1 EP1363305 A1 EP 1363305A1
Authority
EP
European Patent Office
Prior art keywords
pressure switch
cover
membrane
magnets
ballast
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Withdrawn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
EP02425297A
Other languages
English (en)
French (fr)
Inventor
Andrea Ambrosi
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.)
Bonferraro SpA
Original Assignee
Bonferraro SpA
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 Bonferraro SpA filed Critical Bonferraro SpA
Priority to EP02425297A priority Critical patent/EP1363305A1/de
Publication of EP1363305A1 publication Critical patent/EP1363305A1/de
Withdrawn legal-status Critical Current

Links

Images

Classifications

    • 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
    • H01H35/26—Details
    • H01H35/2607—Means for adjustment of "ON" or "OFF" operating pressure
    • H01H35/2614—Means for adjustment of "ON" or "OFF" operating pressure by varying the bias on the pressure sensitive element
    • H01H35/2621—Means for adjustment of "ON" or "OFF" operating pressure by varying the bias on the pressure sensitive element the bias being magnetic
    • 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
    • H01H35/34—Switches operated by change of fluid pressure, by fluid pressure waves, or by change of fluid flow actuated by diaphragm

Definitions

  • the present invention relates to pressure switches, and in particular to an improved pressure switch to be used in domestic appliances.
  • the controlling and restoring of the water level in the tank are carried out by means of a pressure switch which opens and closes the water inflow electric valve.
  • the electric valve is opened when the level decreases below the minimum sustenance value, and is closed just before the water reaches again the normal operating level.
  • the anticipated closure takes into account a certain "inertia" of the system whereby the water continues to enter for some moments after the pressure switch has issued the command for closing the electric valve.
  • a similar drawback occurs in case of failure of the primary pressure switch when the safety pressure switch must intervene.
  • the machine is usually provided with a second pressure switch to avoid that a failure of the primary pressure switch, e.g. the choking of the tube which allows the detection of the pressure in the air trap, causes a flooding due to the lack of intervention thereof.
  • the safety pressure switch when the safety pressure switch detects an excessive water level in the tank it activates the drain pump but also in this case, similarly to the above-described activation of the wash pump, this causes a sudden drop in the pressure especially due to the fine-mesh filter on the tank bottom which hinders the passage of water. As a consequence, the initial pressure drop may reach 40-50 mm of water column, causing the stop of the drain pump and triggering therefore a series of activations and deactivations which jeopardize the operation of the safety pressure switch.
  • these known pressure switches include a plurality of small resisting and biasing springs, strips, contacts and inlets for the passage of current since they make part of the electric circuit they control.
  • Such a structure is quite delicate, in that an erroneous adjustment may cause the blocking of the pressure switch which in fact is usually sold with a factory setting that the user can not change.
  • the object of the present invention is to provide a pressure switch free from said drawbacks. This object is achieved by means of a pressure switch provided with magnetic means, preferably adjustable, to set the restore value. Other advantageous features of the present pressure switch are specified in the subsequent claims.
  • the main advantage of this pressure switch is exactly that of retaining the functionality of conventional pressure switches yet with a structure extremely simple to manufacture, which results in low manufacturing cost and high reliability.
  • Another advantage of the present pressure switch is that of making simpler to adjust the intervention value and to set the restore value, allowing for an adjustment range of the latter which can even extend to zero.
  • the pressure switch according to the invention conventionally includes a container 1, which receives the water, inside which there is arranged a membrane 2 water-tightly secured by means of a cover 4.
  • the novel aspect of this pressure switch is the presence on cover 4 of one or more magnets 7 and a microswitch 5, which is activated by a rod 6 moved by membrane 2 passing through a corresponding hole in cover 4, as well as the presence of a ballast 3 of ferromagnetic material arranged between membrane 2 and rod 6.
  • magnets 7 attract ballast 3 and therefore oppose the action of its weight more and more as it gets close to cover 4.
  • the weight of ballast 3 will operate as a conventional pressure switch during the circuit closure phase (closure of the inflow valve or activation of the drain pump), but then a greater pressure drop will be necessary in order for the weight of ballast 3 to overcome the action of magnets 7 and cause the lowering of rod 6 and therefore the re-opening of the circuit.

Landscapes

  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Control Of Non-Positive-Displacement Pumps (AREA)
EP02425297A 2002-05-15 2002-05-15 Druckschalter Withdrawn EP1363305A1 (de)

Priority Applications (1)

Application Number Priority Date Filing Date Title
EP02425297A EP1363305A1 (de) 2002-05-15 2002-05-15 Druckschalter

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
EP02425297A EP1363305A1 (de) 2002-05-15 2002-05-15 Druckschalter

Publications (1)

Publication Number Publication Date
EP1363305A1 true EP1363305A1 (de) 2003-11-19

Family

ID=29266044

Family Applications (1)

Application Number Title Priority Date Filing Date
EP02425297A Withdrawn EP1363305A1 (de) 2002-05-15 2002-05-15 Druckschalter

Country Status (1)

Country Link
EP (1) EP1363305A1 (de)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN108520841A (zh) * 2018-06-15 2018-09-11 深圳市晶泰电子有限公司 一种磁吸式微动开关

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1275832B (de) * 1959-11-14 1968-08-22 Bosch Gmbh Robert Vorrichtung zum Verhueten des unzeitgemaessen Einschaltens von elektrischen Andrehmotoren fuer Brennkraftmaschinen
GB1203413A (en) * 1966-09-28 1970-08-26 Inertia Switch Ltd Fluid pressure operated electric switches with magnetic restoring means
DE3336469A1 (de) * 1982-10-12 1984-04-12 Mitsubishi Denki K.K., Tokyo Membranvorrichtung mit magneterzeugter hysterese-charakteristik

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1275832B (de) * 1959-11-14 1968-08-22 Bosch Gmbh Robert Vorrichtung zum Verhueten des unzeitgemaessen Einschaltens von elektrischen Andrehmotoren fuer Brennkraftmaschinen
GB1203413A (en) * 1966-09-28 1970-08-26 Inertia Switch Ltd Fluid pressure operated electric switches with magnetic restoring means
DE3336469A1 (de) * 1982-10-12 1984-04-12 Mitsubishi Denki K.K., Tokyo Membranvorrichtung mit magneterzeugter hysterese-charakteristik

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN108520841A (zh) * 2018-06-15 2018-09-11 深圳市晶泰电子有限公司 一种磁吸式微动开关

Similar Documents

Publication Publication Date Title
EP0457137B1 (de) Spender für gelagertes Material und Produkte
US5309939A (en) Safety device for water-conducting household appliances
WO2005115216A1 (en) A washing machine with a flood-preventing mechanism
GB1586342A (en) Washing machine
EP0685671B1 (de) Fluidventil
US3809116A (en) Fluid flow control systems
US20060213561A1 (en) Water flow controller
US4271861A (en) Dishwasher fill level control arrangement
EP1363305A1 (de) Druckschalter
US4178957A (en) Dishwasher fill system
WO2007085931A2 (en) Steam iron
GB2166645A (en) Water inflow control in an appliance operable with water
JP2005065746A (ja) 洗濯機
US4505427A (en) Condensate drain valves
US3209094A (en) Pressure switch with high and low pressure spring adjustments
US4334955A (en) Device for controlling evaporation of a liquid
US5409023A (en) Dishwashing machine with water fill control
US3955791A (en) Pilot operated fluid control valve
US3064094A (en) Pressure switch for washing machine tub level control
US4180085A (en) Dishwasher fill float
GB2156389A (en) Water supply control in a household appliance
US3331374A (en) Water level control
JP2910169B2 (ja) 食器洗い機
GB2090874A (en) Automatic washing machine with improved water supply circuit
US2211440A (en) Float operated switching device

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE TR

AX Request for extension of the european patent

Extension state: AL LT LV MK RO SI

AKX Designation fees paid
REG Reference to a national code

Ref country code: DE

Ref legal event code: 8566

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN

18D Application deemed to be withdrawn

Effective date: 20040520