EP0683263A1 - Pneumatischer Fühler für Sicherheitsgerät zum Sperren von Wasserzufuhrumlauf in Geschirrspülmaschinen, waschmaschinen und dergleichen - Google Patents

Pneumatischer Fühler für Sicherheitsgerät zum Sperren von Wasserzufuhrumlauf in Geschirrspülmaschinen, waschmaschinen und dergleichen Download PDF

Info

Publication number: EP0683263A1
Authority: EP; European Patent Office
Prior art keywords: water; pneumatic sensor; household appliance; electrical household; drum
Prior art date: 1994-05-13
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

Application number

EP95201195A

Other languages

English (en)

French (fr)

Other versions

EP0683263B1 (de

Inventor

Silvano Fumagalli

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.)

Candy SpA

Original Assignee

Candy 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.)

1994-05-13

Filing date

1995-05-09

Publication date

1995-11-22

1995-05-09 Application filed by Candy SpA filed Critical Candy SpA

1995-11-22 Publication of EP0683263A1 publication Critical patent/EP0683263A1/de

1998-09-23 Application granted granted Critical

1998-09-23 Publication of EP0683263B1 publication Critical patent/EP0683263B1/de

2015-05-09 Anticipated expiration legal-status Critical

Status Expired - Lifetime legal-status Critical Current

Images

Classifications

- D—TEXTILES; PAPER
- D06—TREATMENT OF TEXTILES OR THE LIKE; LAUNDERING; FLEXIBLE MATERIALS NOT OTHERWISE PROVIDED FOR
- D06F—LAUNDERING, DRYING, IRONING, PRESSING OR FOLDING TEXTILE ARTICLES
- D06F39/00—Details of washing machines not specific to a single type of machines covered by groups D06F9/00 - D06F27/00
- D06F39/08—Liquid supply or discharge arrangements
- D06F39/081—Safety arrangements for preventing water damage

Definitions

the present invention relates to a pneumatic sensor for a safety device for blocking the water feed circuit of dishwashers, washing machines and the like.
safety block devices are available commercially with the function of interrupting the flow of water inside the internal water circuit of dishwashers or washing machines in the absence of control by valve devices (feed solenoid valve) whereof said machines are provided, or in the event of bursting or perforation of the water feed pipe; otherwise leaks of water occur which lead to damaging floods.
the above devices are characterised in that, following their triggering, they can only be de-actuated by specialist technical staff; thus subsequent start-up of the electrical household appliance is subject to elimination of the fault which has caused triggering of the safety devices themselves.
the latter are also able to detect even small overflows of water inside the machines which, although they do not lead to flooding, cause premature deterioration of the electrical household appliance.
a known safety device consists of a safety valve placed between the pipe coupling for attachment to a tap and the water feed pipe, a spiralled pipe which acts as a sheath for the feed pipe, and a pneumatic sensor, housed in a water collection base placed below the electrical household appliance, fitted with an expander whereto a drum containing air is connected and passed inside the spiralled pipe and, at the opposite end, connected to the safety valve to cause triggering thereof.
the sensitive element of the pneumatic sensor is represented by a highly compressed spongy element which expands when it comes into contact with water, causing the sliding of a piston inside a chamber whereto the drum containing air is connected.
the collection base collects any leaks of water which may result from the overflow (through an anti-overflow drain system normally provided) from the washing drum of the dishwashwer or washing machine following non-intervention by the aforementioned valve devices, or from perforation of the feed pipe, and conveys them to the pneumatic sensor which, in the presence of water, compresses the air inside the drum thus causing triggering of the safety valve, which blocks the water supply of the machine, even with the tap open.
the degree of protection provided by a safety device greatly depends on the triggering time of the pneumatic sensor: the collection base has in fact a limited capacity, due to the fact that the space normally available between the floor and the base of washing machines, and above all dishwashers, is very small. Therefore, before the pneumatic sensor commands closure of the safety valve, the volume of water which has overflowed from the washing drum or leaked from the feed pipe and been conveyed by the spiralled pipe to the collection base may be sufficient for causing an overflow of the latter, and hence flooding.
a second type of safety device which, in place of the pneumatic sensor described, uses a float connected to a microswitch which commands actuation of the drain pump of the electrical household appliance: as soon as the level of water in the collection base raises the float, the microswitch actuates the drain pump which drains all the water contained in the washing drum.
a safety device of this type is however more costly than the previous one, also because a protection device is required for the drain pump to protect it in the event of continuous operation.
a safety device of the second kind is able to prevent the occurrence of flooding for whatsoever type of machine; in fact, again in the specific case of dishwashers, the special anti-overflow system of the washing drum can render the safety device described ineffectual.
dishwashers are sold on the market in whose washing drum a siphon is mounted which triggers when the level of the water in the drum exceeds a predefined safety level in order to transfer the water to the collection base.
This siphon has hysteresis whereby it de-triggers when the level of water in the drum falls below a level lower than this safety level.
the value of said hysteresis is generally such that the volume of water transferred by the siphon to the collection base is greater than the capacity of the latter, which therefore does not hold all the surplus water transferred by the siphon and causes flooding. Actuation of the drain pump also has a limited effect.
a third type of safety device which comprises a pneumatic block device acting directly on the feed solenoid valve when the level of water in the drum exceeds a predetermined value.
the object of the present invention is that of providing a pneumatic sensor for a safety block device of the first kind described above which allows the problems mentioned to be solved simply and economically, and which can be used in electrical household appliances already available on the market.
a pneumatic sensor for a safety device for blocking the water feed circuit of an electrical household appliance comprising a water feed pipe, which can be connected at one end to a respective inlet solenoid valve of a water circuit inside the electrical household appliance, and whereto a respective safety valve, which can be actuated pneumatically, is connected and placed between the opposite end of said feed pipe and a water supply point, a collection base, placed below the electrical household appliance, whereon said pneumatic sensor is placed which comprises expandable water-sensitive means, housed in an expansion chamber, which command actuation of means for compressing a fluid contained in a drum connected to the safety valve, characterised in that said expansion chamber is provided with an inlet which can be connected to a drain conduit of an anti-overflow device of a washing drum of the electrical household appliance, and with gate valve means for closing said inlet following expansion of said water-sensitive means.
the present invention it is possible to produce a safety block with a very short trigger time, since the surplus water in the washing drum of the washing machine or dishwasher is sent directly from the anti-overflow device to the spongy element of the pneumatic sensor, instead of onto the collection base. Since also the drain conduit of the anti-overflow device of the washing drum is closed after the sensor has been actuated, the surplus water in the washing drum is not transferred completely onto the collection base, wherefrom it would overflow, causing a flood, but instead remains in the washing drum, wherefrom it can later be removed following actuation of the drain pump.
the safety device obtained in this way is thus very economical.
the feed pipe 5 is connected to a feed solenoid valve 100 of the dishwasher 1 (Fig.
the pneumatic sensor 7 consists of an external casing 10 in plastic material, hollow inside, whereto are connected the drum 9 and a conduit 11 connected in turn to an anti-overflow drain device whereof a washing drum 12 of the dishwasher 1 is provided.
the anti-overflow device consists of a siphon 13 which extends from the base 14 of the washing drum 12 to inside the latter.
the siphon 13 is made of a vertical pipe 15 having a mouth at a height L1 predefined in relation to the base 14, and a cap 16 which covers the mouth of the vertical pipe 15 and which surrounds for a section I of specific length the vertical pipe 15 itself, so that the lower opening of the cap 16 is at a height L2, lower than L1, in relation to the base 14.
the vertical pipe 15 is connected below to the conduit 11, wherefrom a branch pipe 19 also starts, whereto a breather pipe 20 is connected.
the casing 10 of the pneumatic sensor 7 comprises internally an expansion chamber 21 for a spongy water-sensitive element 17 (Figs. 5 and 6).
the expansion chamber 21 is closed below by a perforated lid 22.
the lid 22 is coupled to the casing 10 in such a way as to leave a gap 102 between it and the collection base 8, so that any layer of water which collects on the base 8 can wet the water-sensitive element 17.
a cursor 23 is housed, sliding vertically, and forced into a lower end-of-stroke position (shown in Figure 5) by a helicoidal spring 24.
the cursor 23 is fitted with a pin 25 which, when the cursor is in the position of Figure 5, is inserted in a respective opening 26 made in a stem 27 of a piston 28 of a cylinder 29 also formed inside the casing 10 (Figs. 2 and 3).
a helicoidal spring 30 elastically forces the piston 28 into the position shown in Figure 3.
the drum 9 is connected to a tubular appendage 31 in one piece with the casing 10 and which leads into the interior of the cylinder 29 (Fig. 3).
a tubular appendage 32 also in one piece with the casing 10, is connected to the interior of the expansion chamber 21 (Figs. 5 and 6); the conduit 11, coming from the siphon 13, is connected to said appendage.
the cursor 23 carries a gate valve 33 which, when the water-sensitive element 17 has expanded and the cursor 23 is in the upper end-of-stroke position shown in Figure 6, closes the tubular appendage 32, from inside the expansion chamber 21, to prevent further flow of water from the siphon through the conduit 11.
the safety device may be triggered by perforations of the feed pipe 5, or by faults in the feed solenoid valve 100 which do not allow adequate control by the programming device, and which lead to feeding of an excessive amount of water into the dishwasher 1.
the spiralled pipe 6 conveys the water leaving the pipe 5 onto the collection base 8.
the level of water on the collection base 8 is such as to wet the water-sensitive element 17 (passing through the holes in the lid 22)
the latter expands in the expansion chamber 21, thus causing the rise of the cursor 23 (compressing the spring 24).
the pin 25 projects from the opening 26 of the stem 27 and, since the elastic force of the spring 30 is no longer balanced, the piston 28 slides inside the cylinder 29, compressing the air inside the drum 9 and causing triggering of the safety valve 2. The flow of water from the tap 4 inside the feed pipe 5 is thus blocked.
the level of water in the washing drum 12 rises until it reaches the level L1 of Figure 4, causing triggering of the siphon 13.
the latter transfers water from the washing drum 12 to the conduit 11, and then directly inside the expansion chamber 21 of the pneumatic sensor 7.
a small quantity of water is sufficient for causing expansion of the water-sensitive element 17 and therefore, wholly similarly to the previous case, blocking of the safety valve 2.
the safety device triggers (i.e. the water-sensitive element 17 expands) very rapidly, greatly limiting the excess quantity of water which is fed into the washing drum 12 of the dishwasher 1.
the gate valve 33 closes the tubular appendage 32, the siphon 13 cannot transfer further water, even if the de-triggering level L2 has not been reached.
the surplus water therefore remains in the washing drum 12 without giving rise to overflows and consequent floods, and wherefrom it can then be eliminated by a drain pump (not shown).
a safety block device comprising a sensor according to the present invention can also be used in washing machines, in addition to dishwashers.

Landscapes

Engineering & Computer Science (AREA)
Textile Engineering (AREA)
Washing And Drying Of Tableware (AREA)
Detail Structures Of Washing Machines And Dryers (AREA)

EP95201195A 1994-05-13 1995-05-09 Pneumatischer Fühler für Sicherheitsgerät zum Sperren von Wasserzufuhrumlauf in Geschirrspülmaschinen, waschmaschinen und dergleichen Expired - Lifetime EP0683263B1 (de)

Applications Claiming Priority (2)

Application Number	Priority Date	Filing Date	Title
ITMI940350U		1994-05-13
IT94MI000350U IT233421Y1 (it)	1994-05-13	1994-05-13	Sensore pneumatico per dispositivo di blocco di sicurezza del circuito di carico idrico di macchine lavastoviglie, lavabiancheria

Publications (2)

Publication Number	Publication Date
EP0683263A1 true EP0683263A1 (de)	1995-11-22
EP0683263B1 EP0683263B1 (de)	1998-09-23

Family

ID=11367995

Family Applications (1)

Application Number	Title	Priority Date	Filing Date
EP95201195A Expired - Lifetime EP0683263B1 (de)	1994-05-13	1995-05-09	Pneumatischer Fühler für Sicherheitsgerät zum Sperren von Wasserzufuhrumlauf in Geschirrspülmaschinen, waschmaschinen und dergleichen

Country Status (4)

Country	Link
EP (1)	EP0683263B1 (de)
DE (1)	DE69504904T2 (de)
ES (1)	ES2123900T3 (de)
IT (1)	IT233421Y1 (de)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number	Priority date	Publication date	Assignee	Title
CN107287843A (zh) *	2017-07-10	2017-10-24	青岛海尔洗衣机有限公司	一种洗衣机贮水槽的防溢出装置及具有该装置的洗衣机
SE2030344A1 (en) *	2019-12-12	2021-06-13	Wet&Lock Oy	Stop valve arrangement

Citations (5)

* Cited by examiner, † Cited by third party
Publication number	Priority date	Publication date	Assignee	Title
DE8420779U1 (de) *	1984-07-11	1986-12-18	Bosch-Siemens Hausgeräte GmbH, 7000 Stuttgart	Niveauregel- und Sicherheitsvorrichtung für wasserführende Haushaltgeräte
DE3718080A1 (de) *	1986-06-20	1987-12-23	Eltek Spa	Ueberlauf- oder ueberschwemm-verhuetungsvorrichtung fuer waschmaschinen
JPS63233343A (ja) *	1987-03-20	1988-09-29	Sanyo Electric Co Ltd	液位検知用圧力センサ−
EP0555679A1 (de) *	1992-01-30	1993-08-18	RE-FLEX S.r.l.	Überschwemmungsschutzvorrichtung für Schläuche an Haushaltsmaschinen
DE4402502A1 (de) *	1993-02-04	1994-08-11	Eltek Spa	Sicherheitsvorrichtung gegen Leckagen, insbesondere für Haushaltswasch- bzw. Spülmaschinen

1994
- 1994-05-13 IT IT94MI000350U patent/IT233421Y1/it active IP Right Grant
1995
- 1995-05-09 ES ES95201195T patent/ES2123900T3/es not_active Expired - Lifetime
- 1995-05-09 EP EP95201195A patent/EP0683263B1/de not_active Expired - Lifetime
- 1995-05-09 DE DE69504904T patent/DE69504904T2/de not_active Expired - Fee Related

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number	Priority date	Publication date	Assignee	Title
DE8420779U1 (de) *	1984-07-11	1986-12-18	Bosch-Siemens Hausgeräte GmbH, 7000 Stuttgart	Niveauregel- und Sicherheitsvorrichtung für wasserführende Haushaltgeräte
DE3718080A1 (de) *	1986-06-20	1987-12-23	Eltek Spa	Ueberlauf- oder ueberschwemm-verhuetungsvorrichtung fuer waschmaschinen
JPS63233343A (ja) *	1987-03-20	1988-09-29	Sanyo Electric Co Ltd	液位検知用圧力センサ−
EP0555679A1 (de) *	1992-01-30	1993-08-18	RE-FLEX S.r.l.	Überschwemmungsschutzvorrichtung für Schläuche an Haushaltsmaschinen
DE4402502A1 (de) *	1993-02-04	1994-08-11	Eltek Spa	Sicherheitsvorrichtung gegen Leckagen, insbesondere für Haushaltswasch- bzw. Spülmaschinen

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
PATENT ABSTRACTS OF JAPAN vol. 13, no. 35 (P - 818) 26 January 1989 (1989-01-26) *

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number	Priority date	Publication date	Assignee	Title
CN107287843A (zh) *	2017-07-10	2017-10-24	青岛海尔洗衣机有限公司	一种洗衣机贮水槽的防溢出装置及具有该装置的洗衣机
SE2030344A1 (en) *	2019-12-12	2021-06-13	Wet&Lock Oy	Stop valve arrangement
SE544088C2 (en) *	2019-12-12	2021-12-21	Wet&Lock Oy	Stop valve arrangement

Also Published As

Publication number	Publication date
ITMI940350V0 (it)	1994-05-13
ES2123900T3 (es)	1999-01-16
ITMI940350U1 (it)	1995-11-13
DE69504904D1 (de)	1998-10-29
EP0683263B1 (de)	1998-09-23
IT233421Y1 (it)	2000-01-28
DE69504904T2 (de)	1999-04-08

Publication	Publication Date	Title
US5028910A (en)	1991-07-02	Drain overflow alarm
US4069837A (en)	1978-01-24	Washing machine overflow control means
GB1586342A (en)	1981-03-18	Washing machine
US4418712A (en)	1983-12-06	Overflow control system
US4522229A (en)	1985-06-11	Safety device for water-pipes
EP0028067A1 (de)	1981-05-06	Waschmaschine mit Verstopfungsanzeige für den Abfluss
US6276894B1 (en)	2001-08-21	Method and device for drawing condensate off from compressed-gas systems
EP0683263B1 (de)	1998-09-23	Pneumatischer Fühler für Sicherheitsgerät zum Sperren von Wasserzufuhrumlauf in Geschirrspülmaschinen, waschmaschinen und dergleichen
US4334143A (en)	1982-06-08	Heater protection arrangement for a washing appliance
GB2166645A (en)	1986-05-14	Water inflow control in an appliance operable with water
AU2016204988B2 (en)	2021-02-18	Drying Method for Washer Dryer with Siphon Filling
US4256136A (en)	1981-03-17	Mechanically operated level control for dishwashers
US4495960A (en)	1985-01-29	Suds return valve for automatic washers
GB2156389A (en)	1985-10-09	Water supply control in a household appliance
US5964001A (en)	1999-10-12	Air dome hose
US2502326A (en)	1950-03-28	Pressure operated switch
GB2161367A (en)	1986-01-15	Dishwashing/laundry washing machine water supply control system
EP0118167A2 (de)	1984-09-12	Waschmaschinen
US3918457A (en)	1975-11-11	Water level control for washing machines
EP0555679A1 (de)	1993-08-18	Überschwemmungsschutzvorrichtung für Schläuche an Haushaltsmaschinen
GB2058148A (en)	1981-04-08	Washing machine having drain blockage indicator
GB2067891A (en)	1981-08-05	Dishwashing machine
US20050051213A1 (en)	2005-03-10	Water- and vibration-sensing protection apparatus
US4930552A (en)	1990-06-05	Drain standpipe
EP1028190A2 (de)	2000-08-16	Detektor für Flüssigkeiten und Überschwemmungsschutzvorrichtung, die einen solchen Detektor verwendet

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