Actuating element and electronic domestic appliance having at least one actuating element

Abstract

An actuating element for an electronic domestic appliance has an electrically non-conductive carrier which defines at least one preferably substantially cylindrical detection portion. A plurality of electrically conductive measuring electrodes is spaced apart from one another along the detection portion of the carrier. A preferably substantially annular operating element is disposed at a first predefined distance from the measuring electrodes and is movable relative thereto. The operating element additionally has at least one sensor portion which is at least partially electrically conductive and is disposed at a second predefined distance from the measuring electrodes. The second predefined distance is different from the first predefined distance, so that a movement of the sensor portion and therefore of the operating element relative to the configuration of measuring electrodes can be detected.

Claims

1. An actuating element, comprising: an electrically non-conductive carrier defining at least one detection portion; a plurality of electrically conductive measuring electrodes spaced apart from one another along said detection portion of said carrier; and an operating element disposed at a first predefined distance from said measuring electrodes and being movable relative to said measuring electrodes; said operating element having at least one sensor portion being at least partially electrically conductive and disposed at a second predefined distance from said measuring electrodes, said second predefined distance being different from said first predefined distance.

2. The actuating element according to claim 1, wherein the actuating element is an electronic domestic appliance actuating element.

3. The actuating element according to claim 1, wherein: said detection portion of said carrier is formed substantially as a lateral surface of a cylinder; and said operating element is substantially annular and is disposed substantially coaxially with said detection portion of said carrier.

4. The actuating element according to claim 1, wherein said operating element is formed of an electrically conductive material.

5. The actuating element according to claim 1, which further comprises at least one of at least one electrically non-conductive insulation element or an air gap provided between said measuring electrodes and said operating element.

6. The actuating element according to claim 1, wherein said operating element is at least partially resiliently deformable.

7. The actuating element according to claim 6, wherein said operating element is deformable up to a third predefined distance from said measuring electrodes, and said third predefined distance is different from said first predefined distance and from said second predefined distance.

8. The actuating element according to claim 6, wherein said operating element is deformable only in regions in which no sensor portion is provided on said operating element.

9. The actuating element according to claim 6, which further comprises at least one of at least one compressible, electrically non-conductive insulation element or an air gap provided between said measuring electrodes and said operating element.

10. The actuating element according to claim 1, which further comprises a control device disposed in or on the actuating element, said measuring electrodes being connected to said control device.

11. The actuating element according to claim 1, which further comprises an actuating element cover facing toward a user, said cover being at least partially permeable to light and having at least one indicating element.

12. An electronic domestic appliance, comprising: an operator control panel; and at least one actuating element according to claim 1.

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

(1) FIG. 1 is a fragmentary, diagrammatic, partly-sectional side-elevational view of an actuating element in accordance with an exemplary embodiment of the present invention;

(2) FIG. 2 is a cross-sectional view of the actuating element illustrated in FIG. 1, which is taken along a section line A-A in FIG. 1 in a first state of actuation; and

(3) FIG. 3 is a cross-sectional view of the actuating element illustrated in FIG. 1, which is taken along the section line A-A in FIG. 1 in a second state of actuation.

DETAILED DESCRIPTION OF THE INVENTION

(4) The above features and advantages as well as further features and advantages of the invention will be better understood from the following description of a preferred non-limiting exemplary embodiment on the basis of the accompanying partly diagrammatic drawings.

(5) The actuating element according to the invention can be used advantageously in electronic domestic appliances for adjusting and selecting different operating parameters (for example a washing program, a rinsing program, a spin speed, a temperature, a cooking time, a cooking setting, etc.).

(6) Referring now to the figures of the drawings in detail and first, particularly, to FIG. 1 thereof, there is seen an actuating element 12 which is attached, for example, to an operator control panel 10, 10 of a domestic appliance, in which the operator control panel is manufactured from plastic or metal. In a variant, the actuating element 12 is placed on the outer side (at the top in FIG. 1) of the operator control panel 10 facing toward a user, in which case electrical connections are guided through a corresponding aperture in the operator control panel 10 or a wireless connection is provided. In another variant the actuating element 12 is slid through an aperture in the operator control panel 10 from behind (at the bottom in FIG. 1), in such a way that the actuating element protrudes from the operator control panel 10 in the direction of the user. In any case the actuating element 12 is mounted fixedly on the operator control panel 10, 10 (for example by adhesive bonding, latching, pressing, screwing, etc.), but is preferably detachable for repair purposes.

(7) As is indicated in FIG. 1 the actuating element 12 is connected to a control device 14 through at least one (wired or wireless) connection line 16. This control device 14, depending on the embodiment of the actuating element 12, may be integrated in the actuating element, attached directly thereto, or positioned separately therefrom.

(8) The structure and operating principle of a preferred exemplary embodiment of the actuating element 12 according to the invention will now be explained in greater detail with reference to FIGS. 1 to 3.

(9) The actuating element 12 formed in this exemplary embodiment as a rotary knob has a knob-shaped carrier 18 formed from an electrically non-conductive plastics material with a substantially cylindrical detection portion 19 having a substantially circular base area and a lateral surface proceeding from the base area substantially in a straight line. A plurality of electrically conductive measuring electrodes 20 is disposed on the carrier 18 along this lateral surface of the detection portion 19.

(10) As is indicated in FIG. 2 the measuring electrodes 20 are each accommodated in recesses or pockets in the carrier 18 and are thus spaced apart from one another and electrically insulated from one another by partition walls of the carrier. In this exemplary embodiment a total of eight measuring electrodes 20 are disposed around the entire circumference of the lateral surface, i.e. along the entire detection portion 19 and in a row over a circle. In this exemplary embodiment the measuring electrodes each have a rectangular basic shape and are curved parallel to the lateral surface of the cylindrical detection portion.

(11) The measuring electrodes 20 are each connected to the control device 14, in such a way that the capacitance values or the capacitance value changes at all measuring electrodes can be detected and evaluated synchronously or sequentially over time.

(12) The detection portion 19 of the carrier 18 is surrounded by an annular, electrically non-conductive insulation element 22 formed from a plastics material. The insulation element 22 is fixedly connected to the carrier 18, for example it is plugged thereon and adhesively bonded thereto in a foot region.

(13) The insulation element 22 is surrounded completely circumferentially in the region of the detection portion 19 of the carrier 18 by an operating element 26, which likewise is substantially annular. The operating element 26 is manufactured from an electrically conductive material, such as metal, preferably stainless steel. As can be seen, in particular, in FIGS. 2 and 3, the operating element 26 is additionally distanced radially from the insulation element 22 through an air gap 24.

(14) As is illustrated by way of example in FIG. 1, the operating element 26 is additionally shaped in such a way that it can be suspended on the insulation element 22. In this case, the operating element 26 is guided only through the insulation element 22, in such a way that it can be rotated relative thereto and therefore also relative to the carrier 18, in particular also relative to the configuration of measuring electrodes 20 around the carrier 18. The operating element 26 is disposed in this case substantially coaxially with the detection portion 19 of the carrier 18.

(15) In this case, depending on the embodiment of the actuating element, the operating element 26 can be rotated endlessly around the carrier 18 or may be limited in terms of its angle of rotation by one or more stops.

(16) Furthermore, the operating element 26 is provided with a sensor portion 28. In this exemplary embodiment this sensor portion 28 is formed by a material reinforcement or an embossing of the metal ring 26, as is illustrated in FIGS. 2 and 3.

(17) If a user contacts the metal ring 26, for example with their finger 32, this metal ring thus forms a capacitor together with each of the measuring electrodes 20, in which case the insulation element 22 and the air gap 24 form a dielectric. The capacitance values may be tapped at the measuring electrodes 20 and evaluated by the control device 14.

(18) As is illustrated in FIG. 2 the operating element 26 is spaced apart from the configuration of the measuring electrodes 20 in the radial direction by a first predefined distance a. The sensor portion 28 of the operating element 26 is by contrast spaced apart from the configuration of the measuring electrodes 20 in the radial direction m by a second predefined distance b, which is different from the first predefined distance (ab). In the present exemplary embodiment the second predefined distance b is smaller than the first predefined distance a (b<a).

(19) If the operating element 26 is now rotated about the carrier 18 by a user using one or more fingers 32, the sensor portion 28 on the operating element 26 thus also moves relative to the measuring electrodes 20. The capacitance values of the capacitors at the measuring electrodes 20 thus change, since the distance between the electrodes 20, 28 and the thickness of the dielectric 22, 24 therebetween change.

(20) Due to a synchronous or sequential querying of the measured values at the measuring electrodes 20, the control device 14 may therefore determine an angle of rotation and/or a direction of rotation of the operating element 26 about the carrier 18. With the aid of such a rotary movement, a user for example may select a program (for example a washing program such as a boil wash, color wash, gentle program, etc.) and/or a desired parameter (for example temperature, spin speed, cooking time, etc.).

(21) In order to confirm a selection made in this way it is possible to provide an additional (mechanical or touch-sensitive) push switch. In a preferred exemplary embodiment of the invention, however, this function is integrated in the actuating element 12.

(22) As is indicated in FIG. 3 the annular operating element 26 is resiliently deformable in the regions outside the sensor portion 28. In this case the insulation element 22 may also be resiliently deformable, in particular compressible, between the operating element 26 and the measuring electrodes 20.

(23) The distance between the operating element 26 and the configuration of measuring electrodes 20 is changed up to a third predefined distance c by exerting a pressure on the operating element 26, for example by using a finger 32 of the user. This third predefined distance c differs both from the first predefined distance a and the second predefined distance b (abc). The clearer these predefined distances a, b, c differ from one another, the greater is the attainable accuracy and reliability when detecting an actuation of the actuating element. The third predefined distance c may be selected optionally to be greater or smaller than the second predefined distance b (c>b or c<b) depending on whether or not the insulation element 22 is compressible.

(24) A change in distance between the operating element 26 and the measuring electrodes 20 to the third predefined distance c causes a corresponding change in the capacitance value at the respective measuring electrode 20. This change in capacitance may be detected by the control device 14 and classified as a pressure actuation of the operating element 26 by the user, for example to confirm their selection made previously by way of a rotary movement of the operating element 26.

(25) In order to simplify the operation, the deformable portions or regions of the operating element 26 are marked for the user, for example optically and/or haptically.

(26) Furthermore, a cover 30 is placed on the carrier 18 on the end face of the actuating element 12 (at the top in FIG. 1) facing toward the user. This cover 30 is, for example, an injection molded part formed from a plastics material. In addition, the cover 30 is fixedly connected to the carrier 18 (for example by pressing, latching, adhesive bonding, etc.).

(27) In a preferred embodiment of the actuating element 12, the cover 30 is at least partially transparent or permeable to light. At least one indicating element 34 is disposed within the carrier 18, as indicated in FIGS. 2 and 3. Information, for example concerning the current parameter settings and the operating state of the appliance, can be displayed to the user by using the indicating element 34.

(28) The indicating element 34 for example is a display. This display 34 is preferably controlled by the control device 14. Besides this display 34, further indicating elements may be provided, for example in the form of light-emitting diode (groups) or optical waveguides coupled to light-emitting diode (groups).