WO2021050015A1

WO2021050015A1 - Rotary control element for a domestic appliance

Info

Publication number: WO2021050015A1
Application number: PCT/TR2019/050761
Authority: WO
Inventors: Ali Erkan MAMUR
Original assignee: Ferel Elektronik San. Ve Tic. A.S.
Priority date: 2019-09-14
Filing date: 2019-09-14
Publication date: 2021-03-18
Also published as: EP4111099A1; EP4111099A4

Abstract

The present invention relates to a rotary control element for a domestic appliance, in particular an oven comprising an inner ring (10) and a radially distant outer ring (20) rotatable with regard to each other, and a mechanical switch turned on or off to selectively conduct electric signals when triggered by the rotary motion between the inner ring (10) and outer ring (20) at a preset angle. The control element further comprises an inner chamber (1 ) confined between an empty radial inner wall (12) of the inner ring (10) and an outer periphery (22) of the outer ring (20) facing the inner wall (12) in which a plurality of mechanical switch elements (40) are disposed in a radially adjacent manner.

Description

ROTARY CONTROL ELEMENT FOR A DOMESTIC APPLIANCE

TECHNICAL FIELD

The present invention relates to control elements used for function selection in domestic appliances and particularly to rotary control elements comprising of multiple switches.

BACKGROUND OF THE INVENTION

In domestic appliances, particularly in ovens, a rotary control element is used to allow the user to select the operation mode or set the cooking parameters of the device. Parts located on a shaft (cam) in the middle of parts known as rotary or commutator switches contacts open and close in order to energize oven devices such as resistances and fans as required. Rotary control elements allow appropriate electrical components to be activated in the required order or combination for a preset operation mode, for example energizing only the top resistance for grilling or activating the fan for air circulation. Rotary control elements are run by rotating a knob attached to the end of a shaft. The shaft connects the center of the rotary control element to the knob. The knob is disposed on a control panel.

EP2938928 describes a rotary control element connected to a knob accessed from the control panel of an oven. When the knob is rotated, the shaft also rotates due to the connection in between the two. The control element delivers a signal to the controlled component when the shaft is rotated, and the knob allows this parameter to be set to the value selected by the user. The communication between the control element and components is controlled via the cables connected to the sockets of the control element.

BRIEF DESCRIPTION OF THE INVENTION

The object of the present invention is to provide an ring control element with multiple mechanical switches for domestic appliances, suitable for use with mains voltage.

To achieve the said objective, a rotary control element for a domestic appliance, in particular an oven comprising an inner ring and a radially distant outer ring rotatable with regard to each other, and a mechanical switch turned on or off to selectively conduct electric signals when triggered by the rotary motion between the inner ring and outer ring at a preset angle. The rotary control element further comprises, an inner chamber confined between an empty radial inner wall of the inner ring and an outer periphery of the outer ring facing the inner wall in which a plurality of mechanical switch elements are disposed in a radially adjacent manner.. Mechanical switches are suitable for working with mains voltage. Therefore, it is possible to place multiple switches radially in the inner chamber to create a rotary control element and to mechanically program a domestic appliance based on the open or closed state of each switch. For example, in an oven, when the first mechanical switch is open because of the preset angle between the inner and outer rings and the second switch is closed, mains power can be supplied to a top resistance of the oven. In another example, the rotation of inner or outer rings at a different angle, for example when both the first and second switches conduct electricity, the rotary control element can power both the top and bottom resistances of the oven. It is possible to develop many more control modes by adjacently placing many more mechanical switches to the inner chamber, with their elongated bodies partially together or completely separated. For example in a rotary control element where 5 switches are adjacently placed, 32 different modes may be developed to send mains power to the relevant units of the appliance. Since the inner ring has an inner space, different functional units, e.g.a display, a light source can be disposed at the center of the rotary control element.

A preferred embodiment of the invention comprises a tracker element that contacts a cam on the inner wall and/or outer periphery on one end and triggers the switch element on the other while allowing the upper contact and a separate and distant lower contact of each switch element to contact through the relative rotational motion of the inner and outer rings and to conduct electric signals. In order to achieve this, it is sufficient to radially push one or both of the upper and/or lower contacts while rotating by the tracker element that follows the cam by making them contact to each other. In a possible embodiment, the cam is disposed on a wall of the inner ring and the tracker element moves towards the outer ring and pushes the lower contact to the fixed upper contact. In alternative embodiments, it is possible for the cam to be disposed on the outer ring and push the upper contact towards the lower contact, or the cam to be disposed on both the inner and outer rings and two tracker elements to push the corresponding upper and lower contacts towards each other while rotating.

A preferred embodiment of the invention, adjacent radial tracker path on the cam path are set to correspond to each tracker element. Radial tracker paths establish a tracker path to each tracker element corresponding to each mechanical switch between the inner and outer rings. Therefore, it is possible to independently program each mechanical switch through the motion between the inner and outer rings. In a preferred embodiment of the invention, the radial tracker path is having at least one radial groove and/or at least one radial protrusion. Grooves and/or protrusions are tracked by the tracker element and when the tracker element reaches a groove it moves radially inwards and when it reaches a protrusion it moves radially outwards in the inner chamber to push or pull the upper and/or lower contact of the corresponding mechanical switch to open or close it.

In a preferred embodiment of the invention, the radial tracker path (163) corresponding to each tracker element is in a ring form adjacent to each other. This enables the tracker elements to stay in the radial tracker path through the rotational motion, and the program skip to the beginning when the ring completes a full circle, preventing it from diverting from the radial tracker path.

A preferred embodiment of the inventions support element is secured at the inner chamber at a distance to the upper contact rest from the movable end of a metal part of a bearing arm of the lower contact at a closed position of the switch element. The support element allows mounting the mechanical switch into the inner chamber. The lower contact lies on the support element and allows mounting the mechanical switch and the upper contact to the inner chamber cavity together.

A preferred embodiment of the invention a housing part receiving the bearing arm is provided opposite the movable end on the tracker element in a manner that elevating the cam and the bearing arm in the radial direction. This allows lifting the bearing arm and tracker element upward in the radial direction and the tracker element to join the lower contact on the bearing arm with the upper contact through the housing part.

A preferred embodiment of the invention comprises a fixing element provided radially outwardly on the outer ring, for being attached to the control panel of a domestic appliance. The fixing part allows fixing the control element on a control panel of the domestic appliance. This allows easy adaptation of the modularly manufactured control element to domestic appliances with the proper electrical connections that correspond to the switches. In this case, the inner ring is rotatable. The outer ring is fixed. In an alternative embodiment, the fixing part can be located on the inner ring to allow vice-versa.

A preferred embodiment of the invention a sleeve extending from at least one the inner wall of the inner ring is equipped with at least one mounting tab. The sleeve allows an additional part, for example a handle to be fixed on the inner ring. This allows the user to to open or close switches and control the domestic appliance by rotating the inner ring with a holding element. In a possible embodiment of the invention, text or graphics may be disposed on such a holding element that indicate the relative positions of the inner and outer rings and to indicate the active control mode.

A preferred embodiment of the invention comprises a plate-shaped side cover in sheet form is mounted to the edges of the inner wall and the outer periphery on the inner ring covering the inner chamber. The side cover protects the inner chamber from dust, dirt and other elements from the environment to block switches to function properly.

A preferred embodiment of the invention comprises a haptic feedback element provided between the inner ring and outer ring, exert a variable force response by relative rotational movement. This element assist rotating the inner and outer rings relative to each other in preset angles in a controlled manner to allow the inner ring to remain fixed in relation to the outer ring inside the full opening or closing regions of the mechanical switches.

BRIEF DESCRIPTION OF THE FIGURES

Figure 1 is a front perspective view of a representative embodiment of the rotary control element according to the invention.

Figure 2 is a perspective view of a rotary control element containing five radially distant mechanical switches, with the front cover open.

Figure 3a is an enlarged view of the rotary control element according to the invention as shown in Figure 2, in a state where the switch is off and not conducting electricity.

Figure 3b is an enlarged view of the rotary control element according to the invention in the embodiment shown in Figure 2, in a state where the switch is on and conducts electricity.

Figure 4 is a perspective view of a representative embodiment of an inner ring alone with an outer sleeve used in the rotary control mechanism according to the invention .

DETAILED DESCRIPTION OF THE INVENTION

In this detailed description, the development of the subject matter of the invention has been described without any limitation and only with references to the examples for a better describe the subject. Figure 1 shows a perspective view of a rotary control element configured to control an oven (not shown). An inner chamber (1 ) is formed between an outer periphery (22) of an outer ring (20) in the form of a hollow cup and the hollow cylindrical inner wall (12) of a concentric inner ring (10). The inner chamber (1 ) has a uniform radial width. A rotatable sleeve (15) is enrobed on the inner ring (10) which extends outwardly . A channel (11) in lengthwise is disposed at the inner side of the inner wall (12). On the other hand, a guide extension (13) in the form of a lateral protrusion and adjacent mounting tabs (14) are disposed on the outer part of the sleeve (15). The channel (11), mounting tabs (14) and guide extension (13) together allow a rotary control element to be attached to an extension protruding from the oven (not shown) through the inner ring (10).

The outer ring (20) is shaped like an hollow cup, and tab like interlocking edge (23) is formed laterally throughout its outer periphery (22). The interlocking edge (23) consists of tabs that are formed by shaping separate and uniform grooves on the outer periphery. A sheet like inner edge (34) is formed in the center of a side cover (30) with a width equal to the width of the inner chamber (1) through circular cut-out. The inner edge (34) is passed through the sleeve (15) of the inner ring (10) and allows the side cover (30) to close the inner chamber (1 ) from the side by radially extending outwards. Grooves (31) provided on a circular outer edge (33) concentric with the inner edge (34) are used to fix the side cover (30) to the interlocking edge (23). Thus, the side cover (30) lies vertically between the sleeve (15) and the outer periphery (22) of the outer ring (20). The side cover (30) is simply pulled out from the sleeve (15) and removed when the inner chamber (1 ) needs to be accessed. Meanwhile, the grooves (31) of the side cover (30) are removed from the interlocking edge (23) to which they are engaged to by applying force. The side cover (30) is axially pushed back into place to reclose the inner chamber (1).

Figure 2 depicts a perspective view of the inner chamber (1) with the side cover (30) removed. Multiple adjacent mechanical switch elements (40) are mounted in the inner room (40). Each switch element (40) includes an upper contact (42) and an adjacent lower contact (44) configured to conduct mains power when in contact with each other. The upper contact (42) includes a metal part (422) fixed to the free end (421) of a hook-like plate. The metal part (422) is a circular flat metal part that provides contact. On the other hand, the hook-like plate is obtained by bending a flat plate in a manner that forms a fixed end (425) with a bearing arm (423) attached to the free end (421 ) and a support bar (424) attached to one end of the bearing arm, successively. The bearing arm (423) is adjacent to the outer periphery of the outer ring (20). The support bar (424) is radially extending outwards in the inner chamber (1). The fixed end (425) extends laterally beneath the support element (43) shaped like an empty flat protrusion joined to the side wall (24) of the outer sleeve (20). The support element (43) is a pin-like protrusion integrated to the side wall (24). It is shaped by axially extending the side wall (24) when manufacturing the cup-like outer ring (20) through plastic injection. The flat metal part (446) of the lower contact (44) on the support element (43) sits on a moving end (445) of the bearing arm (442) that carries it. The bearing arm (442) of the lower contact (44) is in the form of an extruded U-profile rod. A flat bed is provided on the moving arm (445) and the metal part (446) is placed on it. The metal part (446) of the lower contact (44) is placed in a manner that faces the metal part (442) of the upper contact. In the closed position where the switch element (40) isn’t conducting electricity, the moving arm (445) sitting on the support element (43) and the free end (421 ) bearing the metal part (422) of the upper contact (42) are separated by a distance. The other end of the bearing arm (442) of the lower contact (44) sits on a housing part (411 ) on the upper end of a tracker element (41 ). The tracker element (41 ) includes a thin, flat and extruded teeth-shaped tracker extension (412) under the housing part (41 ) with a U cross-section indicating the switching element (40) number. The tracker extension (412) sits on a cam (16) radially formed on the inner wall (12) of the inner ring (10). A gap extends in the middle of the bearing arm (442) and a strip spring (441 ) is longitudinally mounted in this cavity. The strip spring (441 ) contacts the inner wall (12) at its base. A support arm (443) is formed on the bearing arm’s (442) end fitting the tracker element (41) by bending it backwards in parallel to itself. There is a fixed end (425) on the tip of the support arm (443), which contacts the outer periphery (22) of the outer ring (20). The support arm (443) is flexible towards the radial exterior direction. Thus, when a switch element (40) is placed in the inner chamber (1) it contacts the inner wall (12) through a strip spring (441 ) from below and applies pressure to the outer periphery (22) from its fixed end (425) on top, attaching to the outer ring (20).

Figure 3a shows the switch element (40) in its closed state, in which it doesn’t conduct electricity. A step (17) in the form of a radial height where the guide extension (13) connects is formed on the inner wall (12) to separate the sleeve that extends outwards (15) and the elevated cam (16). The bearing arm (442) is placed on the support element (43) from the moving end (445) in a manner that applies downward pressure with its own weight. With the radial pressure force applied by the support part (444) on the outer periphery (22) from inside to the outside, the strip spring (441 ) transmits a radial pressure force towards inside of the cam (16). To ensure this, a secondary switch element (50) and a third switch element (60), which are identical and in the inner chamber (1) apply radial inwards force from different angles and their strip springs (441) hold the inner ring (19) in balance in the center of the outer ring (20), as shown in Figure 1 . When the inner ring (10) is rotated around its center by torque applied through the sleeve (15), the strip springs (441) apply radial inward pressure and ensures that the inner ring (10) rotates due to the friction between its inner wall (12) and the strip springs (441 ). Strip springs (441 ) are flat-shaped and adjusted to allow a user to rotate with the applied torque on the corresponding part of the inner wall (12). As shown in Figure 3a, the distance between the upper contact (42) and the lower contact (44) is maintained because the tracker extension (412) is radially at the bottom of the cam (16). Figure 3b shows the state in which the lower contact (44) contacts the upper contact (42) and the switch element (40) conducts electricity, when the tracker extension (412) is pushed outwards by the cam (16). In this position, as the tracker element (41 ) is radially pushed outwards on the inner wall (12), it lifts the bearing arm (442) it carries on the housing part (411) in the inner chamber (1 ) and allows the moving end (445) to approach the upper contact (42), and the metal part (422) of the upper contact (42) contacts the opposite metal part (446) of the lower contact (44). In this case, the switch element (40) begins conducting electricity with a cable connection (not shown). Position change of the switch element (40 in Figure 3a and Figure 3b is ensured by rotating the inner sleeve (100) at a preset angle. The angle of sleeve (10) at which the tracker element (41) radially changes position upwards or downwards is set by the cam (16). Figure 4 shows the inner ring’s (10) sleeve (15) in perspective view. It shows the adjacent circular cam (16) on the step (17) part of the sleeve (15) on the inner wall (12). Each ring on the cam (16) defines a tracker path (163). The tracker element (41) of each switch element (40, 50, 60) in the inner chamber (1) is placed on the tracker path (163) corresponding to the tracker element (412). Each tracker path (163) has both flat parts and a radially inwards groove (161) or a radially outwards protrusion (162). Thus, the tracker element’s (41) tracker extension (412) advances on the tracker path (163) when the sleeve (15) is rotated and when it arrives at the protrusion (162), it advances outwards, pushing the lower contact (44) towards the upper contact (42) while when it arrives at the groove (161), it allows the lower contact (44) to sit on the support element (43), in a manner that leaves a distance with the upper contact (42). An undulated structure is formed on one edge of the sleeve (15) to create a haptic feedback element (18). A tooth (19) enters the undulated part from the switch element (40) and allows the user to sense the transitions during rotation through force feedback.

REFERENCE NUMBERS

I Inner chamber 40 Switch element 10 Inner ring 41 Tracker element

I I Channel 411 Housing part

12 Inner Wall 412 T racker extension

13 Guide extension 42 Upper contact Mounting tab 421 Free end Sleeve 422 Metal part Cam 423 Bearing arm Groove 424 Support bar Protrusion 425 Fixed end Tracker path 43 Support element Step 44 Lower contact Haptic feedback element 441 Strip spring Tooth 442 Bearing arm Outer ring 443 Support arm Fixing part 444 Support part Outer periphery 445 Moving end interlocking edge 446 Metal part Side wall 50 Second switch element Side cover 60 Third switch element Groove Front wall Outer edge Inner edge

Claims

1- A rotary control element for a domestic appliance, in particular an oven comprising an inner ring (10) and a radially distant outer ring (20) rotatable with regard to each other, and a mechanical switch turned on or off to selectively conduct electric signals when triggered by the rotary motion between the inner ring (10) and outer ring (20) at a preset angle characterized in that an inner chamber (1) is confined between an empty radial inner wall (12) of the inner ring (10) and an outer periphery (22) of the outer ring (20) facing the inner wall (12) in which a plurality of mechanical switch elements (40) are disposed in a radially adjacent manner.

2- A rotary control element according to Claim 1 , wherein a tracker element (41) that contacts a cam (16) on the inner wall (12) and/or outer periphery (22) on one end and triggers the switch element (40) on the other in a manner that allows the upper contact (42) and a separate and distant lower contact (44) of each switch element (40) to contact through the relative rotational motion of the inner (10) and outer (20) rings and to conduct electric signals.

3- A rotary control element according to Claims 2-3, wherein adjacent radial tracker paths (163) on the cam path (16) are set to each corresponding tracker element (41).

4- A rotary control element according to Claim 4, wherein the radial tracker path (163) is having at least one radial groove (161) and/or at least one radial protrusion (163).

5- A rotary control element according to Claims 3-4, wherein the radial tracker path (163) corresponding to each tracker element (41) is in a ring form adjacent to each other.

6- A rotary control element according to Claims 2-5, wherein a support element (43) is secured at the inner chamber (1) at a distance to the upper contact (42) rest from the movable end (445) of a metal part (422) of a bearing arm (442) of the lower contact (44) at a closed position of the switch element (40).

7- A rotary control element according to Claim 6, wherein a housing part (411) receiving the bearing arm (442), provided opposite the movable end (445) on the tracker element (41) in a manner that elevating the cam (16) and the bearing arm (442) in the radial direction. 8- A rotary control element according to any preceding claim, wherein a fixing element (21 ) is provided radially outwardly on the outer ring (20) for being attached to the control panel of a domestic appliance. 9- A rotary control element according to Claim 8, wherein a sleeve (15) extending from the inner wall of the inner ring (10) is equipped with at least one mounting tab (14).

10- A rotary control element according to any preceding claim, wherein a side cover (30) in sheet form is mounted to the edges of the inner wall (12) and the outer periphery (22) on the inner ring (19) to cover the inner chamber (1 ).

11- A rotary control element according to any preceding claim, wherein a haptic feedback element (18) provided between the inner ring (10) and outer ring (20)exert a variable force response by relative rotational movement.