(19) |
|
|
(11) |
EP 1 982 633 B1 |
(12) |
EUROPEAN PATENT SPECIFICATION |
(45) |
Mention of the grant of the patent: |
|
01.12.2010 Bulletin 2010/48 |
(22) |
Date of filing: 16.04.2007 |
|
(51) |
International Patent Classification (IPC):
|
|
(54) |
Dishwasher with rack mounted on rails and roller chains associated thereto
Geschirrspülmaschine mit auf Schienen montiertem Gestell und dazugehörigen Rollenketten
Lave-vaisselle à bâti monté sur rails et chaînes à rouleaux correspondantes
|
(84) |
Designated Contracting States: |
|
AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IS IT LI LT LU LV MC MT NL PL PT RO
SE SI SK TR |
(43) |
Date of publication of application: |
|
22.10.2008 Bulletin 2008/43 |
(73) |
Proprietor: WHIRLPOOL CORPORATION |
|
Benton Harbor
Michigan 49022 (US) |
|
(72) |
Inventor: |
|
- Dabal, Michal
21025 Comerio (IT)
|
(74) |
Representative: Guerci, Alessandro |
|
Whirlpool Europe S.r.l.
Patent Department
Viale G. Borghi 27 21025 Comerio (VA) 21025 Comerio (VA) (IT) |
(56) |
References cited: :
EP-A- 1 552 781 DE-U1-202006 000 711 SU-A1- 1 329 767
|
DE-A1- 10 346 861 JP-A- 2001 253 689 US-A1- 2004 244 825
|
|
|
|
|
|
|
|
|
Note: Within nine months from the publication of the mention of the grant of the European
patent, any person may give notice to the European Patent Office of opposition to
the European patent
granted. Notice of opposition shall be filed in a written reasoned statement. It shall
not be deemed to
have been filed until the opposition fee has been paid. (Art. 99(1) European Patent
Convention).
|
[0001] The present invention relates to a dishwasher with a rack mounted on rails and roller
chains associated thereto. More particularly, the invention relates to a dishwasher
with a rack slidably mounted on rails and roller chains that bend on the flanks of
the rack.
[0002] A typical dishwasher comprises a washing chamber provided with an upper and a lower
rack for holding items to be cleaned. The washing chamber is typically accessible
through a door, and the upper rack is typically mounted on a pair of rails to pull
the rack out of the washing chamber and load it with the items to be cleaned, or unload
it after cleaning. Usually, the rails are movably mounted to opposed walls of the
washing chamber, and the racks include wheels that ride on the rails.
[0003] Several rack and rails systems are known in the art and disclosed in the patent literature.
[0004] EP 1 552 781 A2 discloses a dishwasher comprising a pair of rails that support a sliding rack for
holding items to be cleaned. The rails comprise a plurality of U-shaped elements sliding
telescopically into each other, the end elements being fixed to the walls of the washing
chamber and to the rack, respectively. The elements forming the rails are provided
with holes, to allow circulation of water and avoid deposition of solids within the
cavity of the U-shaped elements. However, a structure of rails formed by elements
sliding telescopically into each other does not ensure optimum stability and perfect
alignment during extension, particularly at a full load condition. Also, the U-shape
of the sliding elements is critical with respect to possible deposit of solid particles
released by the items to be cleaned.
[0005] SU 1 329 767 A1 discloses a dishwasher rack of adjustable length, comprising an upper and a lower
spring holding dishes to be washed, and side walls represented by roller chains with
end portions sliding within channels formed in end walls having the function also
of handles. The rack is designed to be removed from the dishwasher to load/unload
the items to be cleaned. The roller chains allow to adjust the length of the rack
but do not function as support of the rack. The structure of the rack is rather complex
and does not ensure that the items to be cleaned are safely held on the rack during
operation. Also, a disadvantage of this dishwasher is that a series of manual actions
are required to load/unload the rack with the items to be cleaned, including hooking/releasing
the upper and lower springs and pulling/pushing the roller chains in and out the channels
of the end walls. In contrast, customers require dishwashers reliable with respect
to holding the items firmly on the rack, and easy to operate.
[0006] It is therefore the overall object of the present invention to disclose a dishwasher
comprising a rack that is easy to operate, ensures smooth sliding on the rails during
continuous operation, and is relatively not expensive.
[0007] The aforesaid and other objects of the invention, as it will appear from the following
description, are achieved by a dishwasher comprising a washing chamber and a rack
slidably mounted on a pair of rails in the washing chamber, characterized by comprising
a pair of roller chains connected to said rails to form substantially rigid longitudinal
extensions that support said rack during sliding in and out said washing chamber;
and further characterized by:
- said rollers of said chains comprising lower portions preventing downward bending
of said chains,
- said rack comprising housings on the flanks thereof to accommodate said roller chains
in the bent state.
[0008] According to an aspect of the invention, said rollers of said chains comprise bevelled
upper portions allowing upward bending of said chains into said washing chamber.
[0009] According to another aspect of the invention, said roller chains of said dishwasher
are bent upwards within said housings according to a substantially circular path.
[0010] According to a further aspect of the invention, said substantially circular path
is defined by a substantially circular groove formed in said housings, said groove
having a length sufficient to accomodate said roller chain entirely.
[0011] According to still a further aspect of the invention, said rollers of said roller
chains are hinged through pins with axis perpendicular to the longitudinal axis of
said rails, and comprise a front portion with a bottom wall against which the rear
portion of an adjacent roller abuts, so that rotation is limited and downward bending
of the chain is prevented, thereby ensuring alignment of said chains to said rails
during sliding of said rack in and out said washing chamber.
[0012] Some embodiments of the invention will now be described by way of example with reference
to the attached drawings, wherein:
Fig. 1 is a schematic perspective view of a dishwasher according to the invention
with a rack positioned within the washing chamber;
Fig. 2 is a perspective view of the dishwasher of Fig. 1 with the rack in positioned
out of the washing chamber;
Fig. 3, 4 and 5 are perspective views of a part of the dishwasher of Figure 1 or 2
in different operative positions;
Fig. 6 is an exploded perspective view of a part of the dishwasher of Figure 3-5;
Fig. 7 is an enlarged perspective view of an element of the dishwasher of Figure 3-5;
and
Fig. 8 is a front view of the element of Fig. 7.
[0013] With reference to Fig. 1 and 2, a household dishwasher 10 is schematically represented
without front door and with side walls 14,14' partially removed. Dishwasher 10 comprises
a washing chamber 12 and a rack 16 slidably mounted on rails 18,18'. Rack 16 is designed
to hold dishes and other kitchen items to be cleaned, as known in the field. Rails
18,18' are fixed to side walls 14,14' of washing chamber 12. Fig. 1 shows rack 16
within washing chamber 12, typically corresponding to a state of door closed. Fig.
2 shows rack 16 pulled out from washing chamber 12, typically corresponding to a state
of door open when loading/unloading the rack.
[0014] Rack 16 is slidably mounted on rails 18,18a by means of wheels 19 projecting from
supports 20,20' fixed to the flanks of rack 16, as better shown in Figures 3-6. Typically,
wheels 19 comprise a pair of upper wheels and a pair of lower wheels, to allow a stable
and smooth sliding movement of rack 16 on rails 18,18'.
[0015] According to an aspect of the invention, a pair of roller chains 22, 22' is connected
to rails 18,18', to form substantially rigid longitudinal extensions that support
rack 18,18' during sliding movement in and out washing chamber 12.
[0016] Each roller chain 22, 22' consists of a series of roller 24, better shown in Figures
6-8, hinged to each other through pins 26 with axis X perpendicular to the longitudinal
axis of rails 18, 18'. Each roller is hinged to adjacent rollers by means of two pins,
one located in a front portion 23 and the other located in a rear portion 25. Front
portion 23 is formed with a central recess 28 suitable to receive the rear portion
25 of an adjacent roller, so that a pin 26 is inserted into corresponding holes of
the front portion 23 and of the associated rear portion of an adjacent roller to rotatably
connect the two adjacent rollers. Rotation of two adjacent rollers, however, is limited
to a direction above an horizontal plane in which rails 18, 18' lay. This is achieved
by providing front portion 23 of each roller 24 with a bottom wall 29, against which
the rear portion of an adjacent roller abuts, so that rotation in a direction below
an horizontal plane in which rails 18, 18' lay is prevented. Such structure of roller
24 prevents a downward bending of roller chains 22, 22', thereby ensuring that chains
22, 22' are rigidly aligned to rails 18, 18' during sliding of rack 16 in and out
washing chamber 12.
[0017] The upper portion 30 of front portion 23 of each roller 24 is bevelled, so that upward
bending of roller chains 22, 22' is possible.
[0018] Upward bending of chains 22, 22' is effected when rack 16 is pushed into the washing
chamber. To this purpose the flanks of rack 16 are provided with suitable housing
32, 32' for roller chains 22, 22' in the bent state. As shown in Figure 3-6, housings
32, 32' are rigidly connected to supports 20,20' fixed to the flanks of rack 16. Supports
20, 20' and housing 32, 32' are preferably made of a single piece, as shown in Fig.
6 with reference to support 20 and housing 32 for chain 22. Such piece includes also
shafts such as 34 on which wheels 19 are mounted.
[0019] According to an aspect of the invention, roller chains 22, 22' bend within housings
32, 32' according to a substantially circular path, so that any entanglement or blocking
of the motion of the chains caused by a too narrow bend of rollers 24 is prevented.
Also, bending of the chains according to a substantially circular path reduces the
space required to store the chain in the bent state.
[0020] A bending according to a substantially circular path is achieved by providing a substantially
circular groove such as 36 in housings 32, 32'. As shown in Fig. 3, groove 36 has
a length sufficient to accomodate roller chains 22, 22' for their entire length, corresponding
to a state of the rack fully pushed into washing chamber 12, for instance during washing
operation.
[0021] Therefore, roller chains 22, 22' are capable to be in a fully extended position,
as shown by Figure 2 and 5, and in a fully bent position, as shown by Figure 1 and
3, and in all intermediate positions in-between, as shown for example in Figure 4.
[0022] In the fully extended position of Figure 2 and 5, roller chains 22, 22' are aligned
with rails 18, 18', to form substantially rigid longitudinal extensions of rails 18,
18' that support rack 16 during sliding in and out washing chamber 12. The height
of rollers 24 is the same as the height of rails 18, 18', so that there is no discontinuity
in the line of ride of wheels 19 on the passage from rails to chains, thereby a smooth
support to wheels 19 is provided. Side skid and downward bending of the chains are
prevented by the structure and mutual connection of rollers 24. Side skid is prevented
by the coupling of rear portions 25 into recess 28 of front part 23, which allow rotation
about X axis only. Bending downwards is prevented by bottom wall 29 of front part
23, as described above.
[0023] When rack 16 is pushed from the fully extended position in the direction of washing
chamber 12, each chain 22, 22' is forced to bend by engaging circular groove 36, as
shown in Fig. 4. Bending upwards is eased by the bevelled upper portion 30 of rollers
24. In the fully bent state of Fig. 3, chain 22 occupies almost entirely groove 36,
in which it is stored typically when the door of the washing chamber is closed.
[0024] The structure of the rack, rails and roller chains assembly according to the invention
is such to ensure a reliable and continuous operation. Roller chains 22, 22' are preferably
made of a synthetic resin, for example by moulding each component with a suitable
plastic material. This allows to combine the desired mechanical properties with optimum
resistance to wet environment and/or chemical corrosion that could be caused by cleaning
agents and additives used during operation of the dishwasher. Also, support 20 and
housing 32 can be produced in one piece of suitable plastic material, preferably by
injection moulding. Each rail 18, 18' can be produced in a single piece of suitable
plastic material, instead of conventional steel rails, and can be fixed directly to
the walls of washing chamber 12, ensuring also a better stability.
1. Dishwasher (10) comprising a washing chamber(12) and a rack (16) slidably mounted
on a pair of rails (18,18') in the washing chamber, characterized by comprising a pair of roller chains (22, 22') connected to said rails (18,18') to
form substantially rigid longitudinal extensions that support said rack (16) during
sliding in and out said washing chamber (12); and
said rollers (24) of said roller chains (22,22') comprising lower portions (29) preventing
downward bending of said chains (22,22') and
said rack (16) comprising housings (32,32') on the flanks thereof to accommodate said
roller chains (22,22') in the bent state.
2. Dishwasher according to claim 1, characterized in that said rollers (24) of said roller chains (22,22') comprise bevelled upper portions
(30) allowing upward bending of said chains into said housings (32,32').
3. Dishwasher according to claim 1, characterized in that said roller chains (22,22') are bent within said housings (32,32') according to a
substantially circular path.
4. Dishwasher according to claim 3, characterized in that said substantially circular path is defined by a substantially circular groove (36)
formed in said housings (32,32'), said groove (36) having a length sufficient to accomodate
said roller chains (22,22') entirely.
5. Dishwasher according to claim 1, characterized in that said rollers (24) of said roller chains (22,22') are hinged through pins (26) with
axis (X) perpendicular to the longitudinal axis of said rails (18,18'), and comprise
lower portions (29) limiting rotation to prevent downward bending of the chains, thereby
ensuring alignment of said chains (22,22') to said rails (18,18') during sliding of
said rack (16) in and out said washing chamber (12).
6. Dishwasher according to claim 5, characterized in that said lower portions (29) of said rollers (24) limiting rotation comprise a bottom
wall formed in the front portion (23) of each of said roller (24) against which the
rear portion (25) of an adjacent roller abuts, so that downward bending of the chain
is prevented, thereby ensuring alignment of said chains (22,22') to said rails (18,18')
during sliding of said rack (16) in and out said washing chamber (12).
7. Dishwasher according to claim 1, characterized in that said housings (32, 32') for said roller chains (22, 22') are rigidly connected to
supports (20,20') fixed to the flanks of said rack (16).
8. Dishwasher according to claim 7, characterized in that said supports (20, 20') and said housings (32, 32') are made of a single piece.
9. Dishwasher according to claim 1, characterized in that said supports (20, 20') and said housings (32, 32') are made of a single piece of
plastic material.
10. Dishwasher according to claim 9, characterized in that such single piece of plastic material includes also shafts (34) on which wheels (19)
are mounted for sliding movement of said rack (16) on said pair of rails (18,18').
1. Geschirrspüler (10), umfassend eine Spülkammer (12) und ein in der Spülkammer an einem
Schienenpaar (18, 18') gleitbar befestigtes Gestell (16), dadurch gekennzeichnet, dass er ein Rollenkettenpaar (22, 22') umfasst, das mit den Schienen (18, 18') verbunden
ist, damit sie im Wesentlichen steife Längsverlängerungen ausbilden, die während eines
Gleitens in die Spülkammer (12) und aus dieser heraus das Gestell (16) stützen, und
die Rollen (24) der Rollenketten (22, 22') untere Abschnitte (29) umfassen, die ein
Hinunterbiegen der Ketten (22, 22') verhindern, und
das Gestell (16) Gehäuse (32, 32') an den Flanken hiervon umfasst, um die Rollenketten
(22, 22') im gebogenen Zustand aufzunehmen.
2. Geschirrspüler gemäß Anspruch 1, dadurch gekennzeichnet, dass die Rollen (24) der Rollenketten (22, 22') abgeschrägte obere Abschnitte (30) umfassen,
die ein Hochwärtsbiegen der Ketten in die Gehäuse (32, 32') gestatten.
3. Geschirrspüler gemäß Anspruch 1, dadurch gekennzeichnet, dass die Rollenketten (22, 22') gemäß einem im Wesentlichen kreisförmigen Pfad in den
Gehäusen (32, 32') gebogen werden.
4. Geschirrspüler gemäß Anspruch 3, dadurch gekennzeichnet, dass der im Wesentlichen kreisförmige Pfad durch eine in den Gehäusen (32, 32') ausgebildete,
im Wesentlichen kreisförmige Nut (36) definiert ist, wobei die Nut (36) eine Länge
aufweist, die ausreichend ist, damit sie die Rollenketten (22, 22') vollständig aufnimmt.
5. Geschirrspüler gemäß Anspruch 1, dadurch gekennzeichnet, dass die Rollen (24) der Rollenketten (22, 22') durch Stifte (26) mit zur Längsachse der
Schienen (18, 18') senkrechten Achsen (X) eingehängt sind, und untere Abschnitte (29)
umfassen, die eine Drehung begrenzen, um ein Hinunterbiegen der Ketten zu verhindern,
wodurch während eines Gleitens des Gestells (16) in die Spülkammer (12) und aus dieser
heraus eine Ausrichtung der Ketten (22, 22') zu den Schienen (18, 18') sichergestellt
wird.
6. Geschirrspüler gemäß Anspruch 5, dadurch gekennzeichnet, dass die eine Drehung begrenzenden, unteren Abschnitte (29) der Rollen (24) eine Unterteilwand
umfassen, die im Vorderabschnitt (23) der Rollen (24) ausgebildet ist, gegen welche
der Rückabschnitt (25) der benachbarten Rollen anliegt, so dass ein Hinunterbiegen
der Kette verhindert wird, wodurch während eines Gleitens des Gestells (16) in die
Spülkammer (12) und aus dieser heraus eine Ausrichtung der Ketten (22, 22') zu den
Schienen (18, 18') sichergestellt wird.
7. Geschirrspüler gemäß Anspruch 1, dadurch gekennzeichnet, dass die Gehäuse (32, 32') für die Rollenketten (22, 22') steif mit an den Flanken des
Gestells (16) fixierten Stützen (20, 20') verbunden sind.
8. Geschirrspüler gemäß Anspruch 7, dadurch gekennzeichnet, dass die Stützen (20, 20') und die Gehäuse (32, 32') aus einem einzigen Stück hergestellt
sind.
9. Geschirrspüler gemäß Anspruch 1, dadurch gekennzeichnet, dass die Stützen (20, 20') und die Gehäuse (32, 32') aus einem einzigen Stück aus Plastikmaterial
hergestellt sind.
10. Geschirrspüler gemäß Anspruch 9, dadurch gekennzeichnet, dass ein solches einziges Stück aus Plastikmaterial ebenso Wellen (34) aufweist, an denen
Räder (19) für eine Gleitbewegung des Gestells (16) am Schienenpaar (18, 18') befestigt
sind.
1. Lave-vaisselle (10) comprenant une chambre de lavage (12) et un panier (16) monté
de manière coulissante sur une paire de rails (18, 18') dans la chambre de lavage,
caractérisé en ce qu'il comprend une paire de chaînes à rouleaux (22, 22') reliées auxdits rails (18, 18')
pour former des extensions longitudinales sensiblement rigides qui supportent ledit
panier (16) pendant le coulissement dans et hors de ladite chambre de lavage (12)
; et
lesdits rouleaux (24) desdites chaînes à rouleaux (22, 22') comprenant des parties
inférieures (29) empêchant la courbure vers le bas desdites chaînes (22, 22') ; et
ledit panier (16) comprenant des logements (32, 32') sur les flancs de celui-ci pour
accueillir lesdites chaînes à rouleaux (22, 22') dans l'état courbé.
2. Lave-vaisselle selon la revendication 1, caractérisé en ce que lesdits rouleaux (24) desdites chaînes à rouleaux (22, 22') comprennent des parties
supérieures chanfreinées (30) permettant la courbure vers le haut desdites chaînes
dans lesdits logements (32, 32').
3. Lave-vaisselle selon la revendication 1, caractérisé en ce que lesdites chaînes à rouleaux (22, 22') sont courbées dans lesdits logements (32, 32')
selon un chemin sensiblement circulaire.
4. Lave-vaisselle selon la revendication 3, caractérisé en ce que ledit chemin sensiblement circulaire est défini par une rainure (36) sensiblement
circulaire formée dans lesdits logements (32, 32'), ladite rainure (36) ayant une
longueur suffisante pour accueillir lesdites chaînes à rouleaux (22, 22') entièrement.
5. Lave-vaisselle selon la revendication 1, caractérisé en ce que lesdits rouleaux (24) desdites chaînes à rouleaux (22, 22') sont articulés autour
d'axes (26) avec l'axe (X) perpendiculaire à l'axe longitudinal desdits rails (18,
18'), et comprennent des parties inférieures (29) limitant la rotation pour empêcher
la courbure vers le bas des chaînes, assurant ainsi l'alignement desdites chaînes
(22, 22') sur lesdits rails (18, 18') pendant le coulissement dudit panier (16) dans
et hors de ladite chambre de lavage (12).
6. Lave-vaisselle selon la revendication 5, caractérisé en ce que lesdites parties inférieures (29) desdits rouleaux (24) limitant la rotation comprennent
une paroi inférieure formée dans la partie avant (23) de chaque dit rouleau (24) contre
laquelle la partie arrière (25) d'un rouleau adjacent vient buter, de telle manière
que la courbure vers le bas de la chaîne est empêchée, assurant ainsi l'alignement
desdites chaînes (22, 22') sur lesdits rails (18, 18') pendant le coulissement dudit
panier (16) dans et hors de ladite chambre de lavage (12).
7. Lave-vaisselle selon la revendication 1, caractérisé en ce que lesdits logements (32, 32') pour lesdites chaînes à rouleaux (22, 22') sont reliés
de manière rigide à des supports (20, 20') fixés sur les flancs dudit panier (16).
8. Lave-vaisselle selon la revendication 7, caractérisé en ce que lesdits supports (20, 20') et lesdits logements (32, 32') sont faits d'une seul pièce.
9. Lave-vaisselle selon la revendication 1, caractérisé en ce que lesdits supports (20, 20') et lesdits logements (32, 32') sont faits d'une seul pièce
en matière plastique.
10. Lave-vaisselle selon la revendication 9, caractérisé en ce qu'une telle seule pièce de matière plastique inclut aussi des axes (34) sur lesquelles
des roues (19) sont montées pour un mouvement de coulissement dudit panier (16) sur
ladite paire de rails (18, 18').
REFERENCES CITED IN THE DESCRIPTION
This list of references cited by the applicant is for the reader's convenience only.
It does not form part of the European patent document. Even though great care has
been taken in compiling the references, errors or omissions cannot be excluded and
the EPO disclaims all liability in this regard.
Patent documents cited in the description