WO2009018430A1

WO2009018430A1 - Water tight sealing device for a door of a front-loading dishwashing machine and dishwashing machine including such a device

Info

Publication number: WO2009018430A1
Application number: PCT/US2008/071737
Authority: WO
Inventors: Michele Bellini
Original assignee: Premark Feg L.L.C.
Priority date: 2007-08-02
Filing date: 2008-07-31
Publication date: 2009-02-05
Also published as: ITTO20070578A1

Abstract

A water-tight sealing device (1) for a door (2) of a dishwashing machine, wherein a frontal opening for loading/unloading an internal compartment (4) of the dishwashing machine is provided with a peripheral seal (10) provided with a frontal sealing surface (12) facing in use an inner panel (14) of the door intended to abut, with door closed, against the peripheral seal, the inner panel of the door is integrally provided in one piece with a pair of peripheral protrusions (20,21) of the inner panel arranged reciprocally side-by-side and parallel, which are plastically deformed so that in use, with the door closed, a first, peripherally outermost protrusion (20) faces the peripheral seal (10) to cooperate by interference with the frontal sealing surface of the seal, so as to both water- tightly and vapor-tightly seal the inner sealed compartment and so that a second, peripherally innermost protrusion protrudes in use towards the inside of the washing compartment, beyond the frontal sealing surface of the peripheral seal, is arranged in a position peripherally within, and immediately adjacent to, the peripheral seal (10) to define a labyrinth seal towards a peripherally innermost side of the seal itself.

Description

Attorney Docket No. 006593-02291

WATER TIGHT SEALING DEVICE FOR A DOOR OF A FRONT-LOADING DISHWASHING MACHINE AND DISHWASHING MACHINE INCLUDING

SUCH A DEVICE

TECHNICAL FIELD

The present invention relates to a water tight sealing device for a door of an electric household appliance, particularly a water tight and vapor tight sealing device for the door of a front-loading dishwashing machine. The invention further relates to an electric household appliance equipped with such a device.

BACKGROUND

It is known that dishwashing machines, particularly those for professional use (for bars, restaurants, communities, etc.) usually present a front-loading washing compartment closed in use by a pivoting door, e.g. provided with a rotation movement with horizontal axis arranged on a lower edge of the door.

The tightness to the water spray and to the vapor which are produced during the washing operations is performed by means of a sealing device arranged between the perimeter of the door and the perimeter of the opening access to the washing compartment which is, in use, while the dishwasher is running, closed by the door. For example, according to US-A-3603035, such a device comprises a profiled seal peripherally arranged about the door and integrally carried by the door itself and a sealing abutment integrally obtained with the carcass of the electric household appliance all around the access opening, to delimit the latter.

Simpler devices usually contemplate only a labyrinth seal between the door and the peripheral edge of the washing compartment access opening, labyrinth seal obtained by means of a specific profiling of the peripheral edge of the door and/or of the resting abutment for the door itself arranged around the access opening.

The aforesaid devices are not entirely satisfactory. The devices based on a labyrinth seal present relatively large dimensions, may result in zones which are difficult to Attorney Docket No. 006593-02291

clean about the door, may appear ugly and, if not provided with an additional rubber sealing blade, at least at the upper edge of the door, when in use may allow leakages of vapor which, in the long run, may adversely affect the control panel of the dishwashing machine, indeed usually arranged in the immediate proximity of the upper edge.

The devices based on the use of peripheral seals are more efficient, because they do not usually allow accidental leakages of vapor in use; they however require the application in use of a relatively high pressure on the seal, generally obtained by means of relatively rigid door closing springs, which thus require the user to apply a relatively high effort for opening the door.

SUMMARY

It is the object of the present invention to provide a perfected sealing device for the door of a dishwashing machine, and more in general, an at least water tight sealing device for an electric household appliance, which is equally effective both to water and to possible vapor, which is reliable, small, simple, and relatively cost-effective, and which does not cause the formation of zones which are difficult to clean on the door edge. It is a further object of the invention to provide a front-loading dishwashing machine provided with such a device.

The invention thus provides a water tight sealing device for an electric household appliance, as defined in claim 1.

The invention further relates to an electric appliance, as defined in claim 11.

In particular, in one aspect the device according to the invention comprises: a seal integrally carried by a housing of the electric household appliance peripherally arranged around the access opening to an internal compartment of the electric appliance, closed in use by the door, the seal being provided with a frontal sealing surface facing in use an inner panel of the door, intended to abut, with door closed, against the seal; and a pair of protrusions arranged reciprocally side-by-side and parallel, peripherally carried by the inner panel of the door, overhangingly protruding, in use, towards the access opening, which are shaped so that, in use, with the door closed, a first, peripherally outermost Attorney Docket No. 006593-02291

protrusion faces the seal to cooperate by interference with the frontal sealing surface of the same, so as to both water-tightly and vapor-tightly seal the inner sealed compartment, and so that a second, peripherally innermost protrusion protrudes towards the inside of the compartment, beyond the frontal sealing surface of the seal, and is arranged in a position peripherally within, and immediately adjacent to, the seal to define a labyrinth seal towards a peripherally innermost side of the seal itself.

According to a further aspect, the first and second protrusion are integrally obtained in one unitary piece with the inner panel of the door and are defined by corresponding peripheral portions of the inner panel, which is defined by a pressed sheet, which have been plastically deformed so as to protrude in use from the inner panel of the door towards the inner compartment of the electric household appliance.

In this manner, is obtained a sealing device having a simple structure, easy and cost-effective to manufacture, which allows users to easily clean the door edge, and which presents excellent tightness not only to water sprays but also to the vapor possibly generated in use inside the dishwater already without requiring the exertion of a high pressure on the seal, because the labyrinth seal performs a first attenuation of the water and/or vapor jets, and therefore the seal only needs to stop a lesser amount of water, or a vapor already essentially without pressure. Less rigid closing springs can thus be used for the door, increasing user comfort without affecting the sealing action efficiency.

BRIEF DESCRIPTION OF THE DRAWING

Further objects and advantages will be apparent from the description that follows of an embodiment thereof, given only by way of non-limitative example, set forth with reference to the accompanying drawing, which diagrammatically shows an elevation and longitudinal section view of an electric household appliance with horizontal rotation axis pivoting door provided with a sealing device for the door made according to the present invention. Attorney Docket No. 006593-02291

DETAILED DESCRIPTION

With reference to the aforesaid figure, numeral 1 indicates a water tight sealing device for a closing door 2 of an opening access 3 to an internal compartment 4 of an electric household appliance 5, in the preferred embodiment a front-loading dishwashing machine for professional use, in which the door 2 is mobile about a horizontal rotation axis A between a first operating position, shown in the figure, in which the door 2 essentially fluid tightly closes the opening 3, and a second operating position, not shown for the sake of simplicity, in which the door 2 lays turned about the axis A in the direction of the arrow facing downwards, so as to leave free the access opening 3 of the compartment 4, in the case in point consisting of a washing compartment of the dishwashing machine 5.

The device 1 essentially consists of a peripheral water tight sealing device for the door 2 of the dishwashing machine 5, household appliance to which reference will be made hereinafter without, because of this, loosing in generality, having the purpose of exerting a water tight sealing action for both water sprays in the compartment 4 during the normal operation of the dishwashing machine 5, and, for the vapor which is likewise produced during the step of washing, due to the high temperature of the water which is used for washing and for rinsing the dishes present in the compartment 4.

The device 1 comprises a seal 10 integrally carried, according to an aspect of the invention, by a carcass or housing 11 of the electric household appliance 5, peripherally arranged around the access opening 3, and provided with a frontal sealing surface 12, facing in use an inner panel 14 of the door 2, which panel is intended to abut, with door 2 closed, against the seal 10.

The sealing device 1 further comprises in combination with the seal 10, a pair of protrusions 20,21 arranged reciprocally side-by-side and parallel, peripherally carried by the inner panel 14 of the door 2, overhangingly protruding, in use, towards the access opening 3. The protrusions 20 and 21 are shaped so that, in use, with the door 2 closed, a first, peripherally outermost protrusion 20 faces and aligns with the seal 10 to cooperate by interference with the frontal sealing surface 12 of the same, so as to both water-tightly and Attorney Docket No. 006593-02291

vapor-tightly sealing the inner compartment 4 and so that a second, peripherally innermost protrusion 21 protrudes towards the inside of the compartment 4, beyond the frontal sealing surface 12 of the seal 10, and is arranged in a position peripherally within, and immediately adjacent to, the seal 10 to define a labyrinth seal towards a peripherally innermost side 24 of the seal itself.

The first protrusion 20 and the second protrusion 21 may be integrally obtained in one unitary piece with the inner panel 14 of the door 2 of the electric household appliance 5, and are defined by corresponding peripheral portions of the inner panel 14 which have been plastically deformed so as to protrude in use from the inner panel 14 towards the inner compartment 4 of the dishwashing machine 5.

For this purpose, the inner panel 14 of the door 2 is formed by a pressed metal sheet, and the first and second protrusions 20 and 21 are reciprocally connected by a portion 25 of the panel 14 defined by a U-fold of such metal sheet and arranged, in the direction D, between a peripherally outermost side root portion 26 of the first protrusion 20 and a peripherally innermost side root portion 27 of the second protrusion 21.

In particular, the protrusion 21 presents a height H2, measured in a direction D (indicated by the arrow) perpendicular to the access opening 3, higher than the height Hl of the protrusion 20 measured in the same direction D. Furthermore, in such a direction D, the second protrusion 21 is arranged displaced further towards the inside of the inner compartment 4 of the electric household appliance 5 with respect to the first protrusion 20.

Furthermore, the peripheral protrusion 20 of the panel 14 presents, in a cross section thereof, a V-shape having a vertex facing towards the frontal sealing surface 12 of the seal 10 and defined by a rounded convex surface 28 intended to cooperate in contact with the seal 10, with door 2 closed; the second protrusion 21 presents, on the same section, an essentially truncated V-shape, being delimited by an essentially flat surface 29 towards the inner compartment 4 of the dishwashing machine 5.

The sealing device 1 further includes a peripherally outer end edge 30 of the panel 14, right-angle-L-folded on the side of the seal 10 in a aforesaid direction D Attorney Docket No. 006593-02291

perpendicular to the opening 3 and a free end 31 of which overhangingly protrudes, in such a direction D, beyond the protrusions 20 and 21 so as to partially shield, with the door closed, a peripherally outermost side 34 of the seal 10 towards the outside 34 of the washing compartment 4 of the dishwashing machine 5. The seal 10 is carried mounted and driven into a profile 40 having a U-shaped cross section and concavity facing towards the door 2 and is fixed to the carcass or housing 11 of the electric household appliance 5 peripherally around the access opening 3, or at least part thereof.

The seal 10 may be defined by a profile element made of an elastomeric material comprising: a sealing portion 41 having a tubular shape in cross section and defining with a first side 44 thereof, having slightly convex shape in undeformed condition, the frontal sealing surface 12; and an assembly portion 42, integrally obtained in one piece with a second side 43, opposite to the first 44, of the sealing portion 41, essentially C-shaped in cross section.

The other sides 34 and 24, respectively peripherally outermost side and peripherally innermost, of the seal 10 cooperate with corresponding sides of the profile 40 and are each provided with a plurality of peripheral grooves 50, with the purpose of improving both the blocking of the seal 10 in the profile 40, and allowing a static sealing action of the same on the profile 40 itself.

Claims

Attorney Docket No. 006593-02291CLAIMS

1. A water-tight sealing device (1) for a closing door (2) of an access opening (3) to an inner compartment (4) of an electric household appliance (5), in particular to the washing compartment of a dishwashing machine, comprising a seal (10) integrally carried by a carcass (11) of the electric household appliance peripherally arranged around said access opening (3), and provided with a frontal sealing surface (12) facing in use an inner panel (14) of the door intended to abut, with door closed, against said seal; characterized in that it further comprises, in combination, a pair of protrusions (20,21) arranged reciprocally side-by-side and parallel, peripherally carried by the inner panel of the door overhangingly protruding in use towards the access opening, which are shaped so that in use, with the door (2) closed, a first, peripherally outermost protrusion (20) faces said seal to cooperate by interference with the frontal sealing surface (12) of the same, so as to both water-tightly and vapor-tightly sealing said inner compartment (4); and so that a second, peripherally innermost protrusion (21) protrudes towards the inside of said compartment, beyond the frontal sealing surface (12) of the seal, and is arranged in a position peripherally within, and immediately adjacent to, said seal (10) to define a labyrinth seal towards a peripherally innermost side of the seal itself.

2. A device according to claim 1, characterized in that said first and second protrusion (20,21) are integrally obtained in one piece with said inner panel (14) of the door of the electric household appliance (5), and are defined by corresponding peripheral portions of the inner panel (14) which have been plastically deformed so as to protrude in use from said inner panel of the door towards said inner compartment (4) of the electric household appliance.

3. A device according to claim 2, characterized in that said second protrusion (21) presents a height (H2), measured in a direction (D) perpendicular to said access Attorney Docket No. 006593-02291

opening of the electric household appliance, higher than the height (Hl) of said first protrusion (20) measured in the same direction.

4. A device according to claim 2 or 3, characterized in that in said direction (D) perpendicular to the access opening, said second protrusion (21) is arranged displaced further towards the inside of said inner compartment (4) of the electric household appliance with respect to the first protrusion (20).

5. A device according to one of claims from 2 to 4, characterized in that said inner panel (14) of the door consists of a pressed metal sheet, said first and second protrusions (20,21) are reciprocally connected by a portion (25) of said inner panel of the door defined by a U-fold of said metal sheet and arranged, in said direction (D) perpendicular to the access opening, between a peripherally outermost side root portion (26) of the first protrusion and a peripherally innermost side root portion (27) of the second protrusion.

6. A device according to any of the preceding claims, characterized in that said first peripheral protrusion (20) of the inner panel of the door presents, in a cross section thereof, a V-shape having a vertex facing towards the frontal sealing surface of the seal and defined by a rounded convex surface (28) intended to cooperate in contact with the seal, with door closed; said second protrusion (21) presenting, on the same section, an essentially truncated V-shape, being delimited by an essentially flat surface (29) towards said inner compartment of the electric household appliance.

7. A device according to any of the preceding claims, characterized in that it further comprises a peripherally outer end edge (30) of said inner panel of the door, right- angle-L-folded towards of said seal in a direction (D) perpendicular to the access opening and a free end (31) of which protrudes, in such a direction, beyond said first and second Attorney Docket No. 006593-02291

protrusion (20,21) so as to partially shield, with the door closed, a peripherally outermost side (34) of the seal towards the outside of said inner compartment of the electric household appliance.

8. A device according to any of the preceding claims, characterized in that said seal (10) is carried mounted and driven into a profile (40) having a U-shaped cross section and concavity facing towards said door and fixed to said carcass of the electric household appliance peripherally around said access opening or at least part thereof.

9. A device according to claim 8, characterized in that said seal (10) is defined by a profile element made of an elastomeric material comprising: a sealing portion (41) having a tubular shape in cross section and defining with a first side (44) thereof, having slightly convex shape in undeformed condition, said frontal sealing surface; and an assembly portion (42), integrally obtained in one piece with a second side (43), opposite to the first, of the sealing portion, essentially C-shaped in cross section.

10. A device according to claim 9, characterized in that said seal (10) presents a third and a fourth respectively peripherally outermost side (34) and peripherally innermost side (24) cooperating with corresponding sides of said profile (40) and each provided with a plurality of peripheral grooves (50).

11. An electric household appliance (5), in particular a front-loading dishwashing machine, provided with a door (2) mobile about a horizontal rotation axis (A) between a closing position and an opening position, and vice versa, characterized in that it comprises a peripheral hydraulic sealing device (1) of said door according to any of claims from 1 to 10.