EP3447182A1

EP3447182A1 - Household appliance and method for operating a household appliance

Info

Publication number: EP3447182A1
Application number: EP17188024.8A
Authority: EP
Inventors: Alberto Bas; Rodolfo Marcuz; Stefano Morandini; Andrea De Pellegrin
Original assignee: Electrolux Appliances AB
Current assignee: Electrolux Appliances AB
Priority date: 2017-08-25
Filing date: 2017-08-25
Publication date: 2019-02-27
Anticipated expiration: 2037-08-25
Also published as: PL3447182T3; EP3447182B1; WO2019038056A1

Abstract

Household appliance (2), comprising a control panel (62) on which a user interface element is provided which comprises a knob (44) which is associated with a selector, whereby said knob (44) is partially extractable from said control panel (62) from a first inserted position to a second extracted position in which said knob (44) is in a non-operating position but axially constrained by said panel (62) for a complete disassembly from said appliance (2).

Description

Field of the invention

The present invention generally relates to a household appliance, in particular to a laundry treatment appliance, especially a washing machine, dryer or combined washer and dryer, both for domestic and professional use. More particularly, the present invention relates to a laundry treatment appliance comprising a user interface and a rotary user interface element which comprises a knob as well as a method of operation.

Background of the invention

Household appliances, especially laundry machines such as washing machines, dryers, especially tumble dryers, and combined washers/dryers are known which comprise a user interface which can, for instance, be arranged on a front panel. The user interface typically provides several user interface elements for selecting or inputting a desired laundry treatment program and/or related parameters for this program.
The user interface can also provide symbols, lights, displays or other indicators which allow giving the user a feedback on the selected choices. While switches and push knobs are often used, as a selecting device for a treatment program among a set of available programs, a rotary user interface element such as a rotating or rotary knob, which can also have the functionality of a push button, is often provided. By turning the knob, the user can easily select a desired treatment routine.
The rotary user interface element or knob is one of the most important element for operating the machine and is used very often. It is therefore of great importance to ensure a long lifetime and also an accurate operation of this user element.
The rotary user element as the primary interface of the machine transmits the first impression to the user of the quality and handling of the appliance. If the user encounters a user interface element that is easy and convenient to handle and provides a constant, steady and solid feedback, and if she or he fells a smooth passage between the several rotational steps during the rotation of the user interface element, she or he gains a good quality impression of the appliance. If otherwise the user interface element has a shaky, unpredictable, or varying response, resulting for example in a rough and variable force needed for the rotation of the user interface element, the user projects this impression on the appliance and gets an impression of overall low quality. Therefore, the user interface should be reliable and should not block.
Since the knob is often a primary user interface element, its frequent use can lead to damages which make a replacement necessary. Since the knob is protruding from the control panel, also during handling or transport, this element can be damaged and needs to be replaced.
In common machines, the knob can be assembled from the inside / back of the control panel, whereby the knob passes through a control panel aperture and leaves gap such that there is not visual overlapping between knob and control panel from the machine external side. In other embodiments of machines, the knob is assembled from the outside / front of the control panel which leads to a visual overlapping between the knob and the control panel, leaving a gap under the knob.
In both cases there are mechanical constraints that prevent the removal of the knob by pulling it by hand. In cases when the knob needs to be exchanged, for example due to quality issues (e.g. scratches made during the assembly phase), the operator must disassemble the control panel assembly from the machine, dissemble the electronic subassembly from the control panel and then remove the knob. This sequence of operations takes usually a comparatively long time to perform, increasing the risks of components damages, due to the control panel/electronic board disassembly.

Summary of the invention

The aim of the invention is to provide a household appliance allowing a quick, a robust and a reliable removal of the knob.
It is a further aim of the invention to provide a method for operating a household appliance which yields a quick, a robust and a reliable knob removal.
The invention therefor relates to a household appliance, comprising a control panel on which a user interface element is provided which comprises a knob which is associated with a selector, whereby the knob is partially extractable from the control panel from a first inserted position to a second extracted position in which the knob is in a non-operating position but axially constrained by the panel for a complete disassembly from the appliance.
The invention is based on the consideration that it is desirable to allow a quick and convenient removal of the knob without the need of the disassembly of further components. The knob at the same time should still make a qualitatively high and pleasant impression. Current solutions make a rather high demand on time and working steps for the removal of the knob.
Applicant has found that these demands can be met by designing the knob in such a way that it can be removed in a two-step process. The knob can first be put into a non-operating position in which it is axially constrained. There is thus not the danger that it can be too easily removed or pulled out. In this position, the knob is accessible for dissemble from the panel, preferably by a tool.
In the first inserted position, the knob, in its normal operating condition, is operational and functions as a user interface element. In the second extracted position, the knob is configured to be detachable but cannot be ditched by further pulling which would eventually destroy the knob. Its detachment is only possible by actively, especially by using a tool, disengaging the knob.
Preferably, especially only, in the second position, the knob is at least partially removable from the control panel.
In a preferred embodiment, the knob comprises a knob cover element and a knob carrier element or underknob, whereby the knob cover element is removably attached to the knob carrier element, and whereby the knob carrier element is, especially in an axial direction of the knob, slideably arranged at least partially behind the control panel. This design is based on the recognition that damages occur typically on the part of the knob protruding form the control panel. When the knob is built in the described two-part design, the carrier element can remain behind the control panel since only the cover element needs to be replaced. The two-part structure therefore enables a convenient replacement without trade-offs in stability or reliability of the knob.
Advantageously, the knob cover element is fully detachable from the knob carrier element by the user in / only in the second position. It thus can be removed and replaced by a new cover element which can be attached / connected to the carrier element.
Preferably the knob cover element and the knob carrier element are attached to each other by a snap connection / fastening means. This design allows a quick detachment of these two components.
The knob carrier element preferably comprises at least one hook seat into which in the attached configuration at least one snap hook of the knob cover element engages. In another embodiment, the hooks are arranged on the carrier element and engage with hook seats on the cover element.
The knob carrier element preferably comprises an external flange acting as an axial block when the second extracted position of the knob is reached. In this way, when the knob cover is pulled away from the control panel, a natural stop is realized indicating a second position which is suitable for disengagement of cover and carrier elements.
This flange in the second extracted position preferably is blocked by blocking means / an abutting element or portion, preferably a sleeve, of the control panel. These means, especially this sleeve is therefore arranged behind an outer surface of the control panel and in front of / in contact of the flange of the carrier element when fully inserted.
Advantageously the knob carrier element is slideably arranged with respect to / on the selector.
Preferably, in the assembled position of the knob cover element and the knob carrier element, between these two elements a, preferably radial, aperture is provided which is configured to allow the insertion of a tool when the knob is arranged on its second extracted position.
Preferably, said tool is configured to allow the cover element disassembly, i.e. the removal of the cover element from the carrier element. The concrete design of the tool can depend on the concrete attachment of these two components. For example, it can be built as a pen- or bolt-type device for disengaging snap elements, especially hooks.
The knob cover preferably is non-rotatable mounted on the knob carrier element. Knob cover and knob carrier element in this way rotate together in a collinear way with the same angular velocity, i.e. they don't change their relative orientations during rotation. When the knob cover is turned by the user, the knob cover transmits the same rotational movement to the carrier element.
The knob carrier element advantageously comprises means interacting with an encoder. Preferably, the encoder is provided on an electronic board provided on the rear side of the knob, said encoder preferably comprising a base connected to the electronic board and a rotatable pin, the rotation of which result in a different signal used by the machine control unit to select the program / parameter.
Preferably the material of the knob cover and/or the knob carrier element is A.B.S. (Acrylonitrile butadiene styrene).
Advantageously, the household appliance is built as a laundry treatment machine. Most preferably, it is built as a washer, a dryer or combined washer/dryer. It preferably is built as a front-loading washing machine or washer / dryer.
The invention also relates to a method for operating a household appliance previously described, with the steps of

pulling the knob cover element away from the control panel until the knob reaches the second extracted position;
detaching the knob cover element from the knob carrier element.

The knob cover element is preferably attached to knob carrier element by snap elements or hooks which in the mounted position engage in respective seats.
Preferably the tool is inserted into a, preferably radial, aperture between these two elements which is designed to allow the insertion of a tool when the knob is arranged on its extracted position.
Preferably the tool is inserted for disengaging connection elements located on cover and/or carrier elements such that the cover element is not attached anymore to the carrier element and can be disengaged and removed. For initial assembly or replacement, the respective cover element is attached the carrier element. The cover element is then pushed towards the control panel until cover and carrier elements reach the first position in which the knob is operational as a user interface element.
The advantages of the invention are essentially as follows. Due to the design of the knob which can assume two positions of which the second allows a disassembly of the knob, it can be replaced very quickly, assuring at the same time a easier way of knob disengagement. For its replacement, the control panel and electronic subassemblies do not need to be removed or disassembled. Moreover, the removal of the electronic subassembly from the control panel is made easier since the encoder's pin is not fixed inside the knob.

Brief description of the drawings

Further features and advantages of the present invention shall become clearer from the following detailed description of some of its preferred embodiments, made with reference to the attached schematic drawings and given as an indication and not for limiting purposes.
In particular, the attached drawings are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification. The drawings together with the description explain the principles of the invention. In the drawings, corresponding characteristics and/or components are identified by the same reference numbers. In these drawings:

FIG. 1: shows a household appliance with a knob in a preferred embodiment in a perspective view;
FIG. 2: shows the household appliance according to FIG. 1 in a frontal view;
FIG. 3: shows a knob cover element;
FIG. 4: shows a knob carrier element;
FIG. 5: shows knob cover element and knob carrier element mounted on the control panel of the household appliance in a first position;
FIG. 6: shows knob cover element and knob carrier element mounted on the control panel of the household appliance in a second position;

In FIGs 1 and 2, a household appliance 2 is shown which is built as a front-loading washing machine and comprises a housing or casing 6 with a preferable parallelepiped shape, the casing 6 comprising a front wall 10, two side walls 14, a cover plate 20 and a rear wall (not shown). Front wall 10 and side walls 14 are preferably part of a cabinet. A front door 24 is provided which can be opened for loading or unloading laundry through an opening 28 into a washing drum. Front door 24 comprises a handle 32 for convenient opening and closing.
Advantageously a washing tub is contained within casing 6, whereby a rotatable and perforated drum is contained by said washing tub. Both washing tub and drum have a substantially cylindrical shape. Advantageously the tub is suspended in a floating manner inside casing 6 by means of a number of coil springs and shock absorbers. The drum is rotated by an electric motor (not shown), which transmits the rotating motion of a motor shaft to the drum by a belt/pulley system. In a different embodiment of the invention, the motor can be directly associated with the shaft of the drum. The tub is preferable connected to casing 6 by means of an elastic bellows or gasket. Alternatively, the laundry appliance can be a dryer (in which case the tub is not provided) or a combined washer and dryer.
The preferred washing machine shown in FIGs 1 and 2 on a front panel 48 comprises a drawer 30 with a front plate 34 and a handle 38 for pulling out and pushing back the drawer 30. Drawer 30 preferably comprises at least one compartment for detergent or washing additives. Preferably, adjacent to drawer 30, a rotatable or rotary knob 44 is arranged for selecting a laundry treatment program and/or at least one parameter of a laundry treatment program. Knob 44 is preferably provided on a control panel 62 or user interface which can provide further indicating and/or control elements. Knob 44 is preferably arranged on front panel 48 adjacent to drawer 30, whereby preferably no user interface elements such as controls (buttons, dials) or indicating elements (displays, lights) are arranged between drawer 30 and knob 44. On a panel 64 which is part of control panel 62, user interface elements such as at least one display and/or buttons and/or indicators can be provided. A service hatch 70 is preferably provided on front wall 70 which preferably yields access to a filter unit.
The knob 44 shown in FIGs. 1 and 2 comprises a knob cover element 70 shown in FIG. 3 and a knob carrier element 72 shown in FIG. 4. Knob cover element 70 preferably has a circular shape and preferably comprises at least one region 74, 76 of corrugated surface which allow the user to conveniently operate the knob 44 by preventing that the users fingers slide on the perimeter of the knob 44 when turning it. Cover element 70 preferably comprises a further corrugated region 78, whereby centrally in this region 78, an indicating element 82 is arranged which protrudes from an outer perimeter 86 of cover element 70. Indicating element 82 is arranged in cover element 70 preferably in such a way that indicating element points vertically upwards when knob 44 does not correspond to a specific setting of an appliance parameter / program. Cover element 70 comprises a circular front surface 88 which is preferably concavely shaped (see Figs 5 and 6).
As can be seen in FIG. 4, carrier element 72 has a circular base portion or flange 90 from which a first part 94 protrudes. From first part 94 a central part 98 and two pins 100, 102 protrude which are arranged on opposite sides of central part 100. Part 94 preferably comprises, preferably on opposing sides, hook seats 110, 112 into which hooks 120, 122 of cover element 70 engage (see Figs 5 and 6).
Pins 100, 102 have two functions: to assist the positioning of cover element 70 on carrier element and to reduce clearances. Regarding the positioning function, pins 100, 102 have different diameter and engage with / are received in two holes provided on a backside of cover element 70 which in the mounted position faces the control panel 62. The two holes have corresponding diameters, resulting in the fact that the cover element 70 can only in one prescribed orientation be mounted on carrier element 72, avoiding mistakes regarding the assembly of these two components.
The pins 100, 102 additionally serve to reduce clearances between cover element 70 and carrier element 72. Since hooks 120, 122 do not eliminate all possible displacements between elements 70 and 72, the pins 100, 102 together with the respective holes in cover element 70 eliminate possible remaining clearances / play between these two components. They determine the distance between these two components 70, 72 when the pins are fully inserted in the respective holes and prevent also lateral respective movements as well as rotational play.
In FIG. 5, knob 44 with cover element 70 and carrier element 72 is shown in a mounted position on control panel 62. Carrier element 72 is preferably rotatable mounted on a carrier seat element 130. The carrier seat element 130 provides an axial stop in direction opposite to axial direction 160. In this position, the knob 44 is fully functional. A rotatable pin 142 being part of a selector which is connected to an electronic board of the appliance 2 is received by central opening preferably provided on central part 98 of the carrier element 72 on its side facing control panel 62. Snap hooks 120, 122 of cover element 70 are engaged in hook seats 110, 112 of carrier element 72.
The encoder of appliance 2 preferably comprises a base connected to the electronic board and a rotatable pin 142, the rotation of which result in a different signal used by the machine control unit to select the program / parameter.
The hole in central part 98 has in the preferred embodiment shown an asymmetric cross section throughout its depth, corresponding to the cross section of pin 142. When in the mounted configuration pin 142 is received by opening on the central part 98, when cover element 70 and carrier element 72 co-rotate, pin 142 is rotated. In the second extracted position of knob 44 below described, the pin 142 is still at least partially located in opening 98. Thus, when cover element 70 is rotated, still the pin 142 is rotated.
In an alternative embodiment, the opening on the central part 98 can have a circular cross section in a region facing the control board and a asymmetric cross section in a region opposite to control board in such a way that in the first or fully inserted position, pin 142 engages with the asymmetric part and is turned when cover element 70 is turned. In the second extracted position below described, however, pin 142 is located in the circular region of opening 98 in such a way that a rotation of cover element 70 and carrier element 72 does not lead to a rotation of pin 142.
In the configuration displayed, the cover element 70 and carrier element 72 are fixed with each other both in an axial direction 160 as well as radial direction, i.e. both elements 70, 72 rotate collinearly with each other with the same angular velocity when the cover element 70 is turned by the user. The configuration shown in FIG. 5 is a first, fully inserted configuration of knob 44 in which the household appliance 2 is operated.
In FIG. 6, a second configuration of knob 44 is shown. Both cover element 70 as well as carrier element 72 are translated in axial direction 160 compared to the configuration shown in FIG. 5. The maximal stroke by which carrier element 72 can be moved in axial direction 160 is limited by a, preferably circular, sleeve 166 of control panel 62. At this maximal stroke a second positon of knob 44 is defined in which flange 90 touches sleeve 166 by which further movement in axial direction 166 is blocked. In this position, knob 44 is not functional but prepared for full detachment of the knob cover element 70. Between cover element 70 and the carrier element 72 a radial aperture 170 is formed which is in this second position accessible by a tool. In the present configuration shown in FIG. 6, a tool can be inserted into aperture 170 in order to disengage cover element 70 from carrier element 72. This is achieved by disengaging snap hooks 120, 122 from seats 110, 112. Snap hooks 120, 122 and/or seats 110, 112 are built elastically and can be preferably disengaged one after the other or simultaneously. When both hooks 120, 122 are disengaged, cover element 70 is disengaged from carrier element 72 and can be fully removed.
The knob replacement is therefore performed as follows. In a first step, starting from the configuration shown in FIG. 5, knob cover element 70 is pulled in axial direction 160 until a mechanical resistance is detected when movement of flange 90 is stopped by sleeve 166. Until this position has reached, cover element 70, which is engaged with carrier element 72, and carrier element 72 move together in axial direction 160.
When this second position is reached, the aperture 170 between cover element 70 and carrier element 72 is accessible. A tool, preferably a screwdriver, is inserted into aperture for disengaging hooks 120, 122 from respective hook seats 110, 112. Cover element 70 can now be removed, leaving behind carrier element 72. The tool is suitable for this disengagement and is preferably provided with the appliance 2 to the user.
For initial assembly and/or replacement, another cover element 70 is connected to carrier element 72 by engaging hooks 120, 122 of cover element 70 with hook seats 110, 112 of carrier element 72. Pins 100, 102 described above engage with corresponding holes in cover element 70 and assure a correct rotational orientation of cover element 70 and carrier element 72 with respect to each other. Also they center elements 70, 72 and reduce clearances and play. Both elements 70, 72 can be pushed towards the control board 62 in a direction opposite to axial direction 160 until the first and fully inserted position is reached in which carrier element 72 is seated on carrier seat element 130.
The invention thus conceived can be subjected to numerous modifications and variants all falling within the scope of the inventive concept.
In addition, all details can be replaced by other technically equivalent elements. In practice, all the materials used, as well as the shapes and contingent dimensions, may vary depending on the requirements without departing from the scope of protection of the following claims.

Claims

Household appliance (2), comprising a control panel (62) on which a user interface element is provided which comprises a knob (44) which is associated with a selector,
characterized in that
said knob (44) is partially extractable from said control panel (62) from a first inserted position to a second extracted position in which said knob (44) is in a non-operating position but axially constrained by said panel (62) for a complete disassembly from said appliance (2).
Household appliance (2) according to claim 1, whereby in said second position, said knob (44) is at least partially removable from said control panel (62).
Household appliance (2) according to claim 2, whereby said knob (44) comprises a knob cover element (70) and a knob carrier element (72), whereby said knob cover element (70) is removably attached to said knob carrier element (72), and whereby said knob carrier element (72) is slideably arranged at least partially behind said control panel (62).
Household appliance (2) according to claim 3, whereby said knob cover element (70) is fully detachable from said knob carrier element (72) by the user in / only in said second position.
Household appliance (2) according to claim 3 or 4, whereby said knob cover element (70) and said knob carrier element (72) are attached to each other by a snap connection/fastening means.
Household appliance (2) according to claim 5, whereby said knob carrier element (74) comprises at least one hook seat (110, 112) into which in the attached configuration at least one snap hook (120, 122) of said knob cover element (70) engages.
Household appliance (2) according to one of the claims 3 to 6, whereby said knob carrier element (72) comprises an external flange (90) acting as an axial block when said second extracted position of said knob (44) is reached.
Household appliance (2) according to claim 7, whereby said flange (70) in said second extracted position is blocked by a blocking means (166) of said control panel (62).
Household appliance (2) according to one of the claims 3 to 8, whereby said knob carrier element (72) is slideably arranged with respect to / on said selector.
Household appliance (2) according to one of the claims 3 to 9, whereby in the assembled position of said knob cover element (70) and said knob carrier element (72), between said two elements (70, 72) an aperture (170) is provided which is configured to allow the insertion of a tool when said knob (44) is arranged on said second extracted position.
Household appliance (2) according to one of the claims 3 to 10, whereby said knob cover element (70) is non-rotatable mounted on said knob carrier element (72).
Household appliance (2) according to one of the claims 3 to 11, whereby said knob carrier element (72) comprises means interacting with an encoder.
Household appliance (2) according to one of the claims 3 to 12, whereby the material of the knob cover and/or the knob carrier element is A.B.S. (Acrylonitrile butadiene styrene).
Household appliance (2) according to one of the claims 3 to 13, which is built as a laundry treatment machine.
Method for operating a household appliance (2) according to one the claims 3 to 14, with the steps of
• pulling said knob cover element (70) away from said control panel (62) until said knob (44) reaches said second extracted position;

• detaching said knob cover element (70) from said knob carrier element (72).