DE102020209194B4 - push button - Google Patents

Abstract

A push button (10) comprising: a cover (12) having a user side (12a) facing a user and an inner surface (12b) facing away from the user, the cover (10) defining a keypad (14), the cover (12) in the keypad (14) is at least partially elastically deformable, and the cover (12) in the keypad (14) has an IR transmission area (15) in which the cover (12) is designed to be permeable to IR light, and an IR - Reflection area (16) in which the cover (12) is designed to reflect IR light; anda sensor device (18) arranged on the inner side (12b) side of the cover (12) for detecting an actuation state of the keypad (14),wherein the sensor device (18) comprises:a transmitter (19) for emitting IR light (e1 ) towards the IR transmission area (15) of the cover (12) and IR light (e2) towards the IR reflection area (16) of the cover (12);a first receiver (20) for detecting an object (17) IR light (r1) reflected on the user side (12a) of the IR transmission range (15) of the cover (12); anda second receiver (21) for detecting an IR light (r2) reflected from the IR reflection area (16) of the cover (12), and further comprising:at least one light emitter arranged on the side of the inner side (12b) of the cover (12). (26) for emitting visible light (o1) into the cover (12); at least one light deflector (30) arranged in the cover (12) for deflecting (o2) the visible light (o1) of the light emitter (26) in the parallel direction to the plane of the cover (12); andone or more light decoupling elements (28) arranged in the cover (12) for decoupling (o3) the visible light (o2) from the light deflector (30) out of the user side (12a) of the cover (12).

Description

The present invention relates to a push button, in particular a multifunctional push button, for example for use in electronic household appliances.

Various types of operating elements with different functionalities are known for operating devices. In the case of the control elements designed as pushbuttons, a distinction can be made between touch and/or proximity-sensitive pushbuttons (so-called “touch control”) and pushbuttons that can be actuated by the action of force. In practice, mostly optical or capacitive sensor devices are used to detect the actuation state of such pushbuttons.

The WO 2017/174097 A1 discloses a multifunctional pushbutton with an optical sensor device, in which the optical sensor device can differentiate between actuations of the keypad with different pressing forces depending on a detection location of the reflected radiation. With this design, the radiation emitted by the transmitter of the sensor device is reflected by the back of the cover plate and then detected by the receiver of the sensor device, with the location of the detection of the radiation reflected by the cover plate being evaluated in order to draw conclusions about the degree of deformation of the cover plate corresponding to different forces acting on the keypad.

From the DE 10 2019 000 752 A1 a pushbutton with an optical sensor arrangement is known which can differentiate between approaching a cover plate, touching it and pressing or elastically deforming the cover plate.

It is the object of the invention to create an improved multifunctional pushbutton which, in particular, also enables greater variability in the design of the entire operating device.

This object is achieved by a push button having the features of claim 1. Particularly advantageous configurations and developments of the invention are the subject matter of the dependent claims.

The push button according to the invention has a cover with a user side facing a user and an inner side facing away from the user, the cover defining a keypad, the cover in the keypad being at least partially elastically deformable, and the cover in the keypad having an IR transmission area in which the cover is designed to be permeable to IR light, and an IR reflection area in which the cover is designed to be reflective to IR light. The push button according to the invention also has an optical sensor device arranged on the side of the inside of the cover for detecting an actuation state of the keypad, the sensor device having a transmitter for emitting IR light in the direction of the IR transmission area of the cover and IR light in the direction of the IR reflection area of the cover; a first receiver for detecting an IR light reflected from an object on the user side of the IR transmission range of the cover; and a second receiver for detecting an IR light reflected from the IR reflection area of the cover. Furthermore, the pushbutton has at least one light emitter arranged on the side of the inside of the cover for emitting visible light into the cover, at least one light deflector arranged in the cover for deflecting the visible light of the light emitter in a direction parallel to the plane of the cover, and one or more light decoupling elements arranged in the cover for decoupling the visible light from the light deflector out of the user side of the cover.

This construction of the pushbutton with two different IR reflection paths via the IR transmission range or the IR reflection range of the cover in its keypad enables the detection of several different actuation states of the keypad of the pushbutton, namely on the one hand touching or approaching the keypad and on the other hand pressing on the keypad, with a relatively simply constructed optical sensor device. The construction of the pushbutton according to the invention also allows the use of translucent covers or cover plates, which in turn enables simple and variable symbol illumination of the pushbutton, the IR light from the sensor device and the visible light from the symbol illumination not interfering with one another, even if they cross one another. The optical sensor device or its components can also be arranged relatively flexibly, so that the push button can be adapted very flexibly to various desired designs of the entire operating device. That is, the construction according to the invention provides a multifunctional push button with several different actuation states that can be detected, which also allows a variable configuration of a symbol illumination and a flexible adaptation to desired designs.

The transmitter of the sensor device can have one or more transmitter elements for emitting Have IR light. The first and second receivers of the sensor device are preferably equipped for spatially resolved detection of IR light, ie for detecting a detection location within the respective receiver at which the IR light arrives. For this purpose, the first and the second receiver can optionally each contain a plurality of receiving elements.

With this configuration, the positioning of the light guide and light decoupling for possible symbol illumination of the pushbutton is possible independently of the placement of the components of the sensor device and in a different plane than the components of the sensor device, as well as the great variability of the symbol illumination through the light decoupling elements within the cover. In principle, the one or more light decoupling elements can be arranged anywhere in the cover outside of the IR transmission area in the keypad, i.e. in particular outside of the keypad and also in the area of the IR reflection area of the keypad.

Preferably, the sensor device also has a control device which is designed to determine a distance or a change in distance from the object (e.g. the user's finger) to the first receiver from the IR light detected by the first receiver and to determine a distance or a change in distance from the cover to the second receiver from the IR light detected by the second receiver.

This control device can preferably be designed to recognize, depending on the determined distance or the determined change in distance from the object to the first receiver, when an object has touched the keypad and/or an object has approached the keypad as possible actuation states of the keypad or the pushbutton. The control device can preferably also be designed to recognize, depending on the determined distance or the determined change in distance from the cover to the second receiver, a deformation or a degree of deformation of the keypad due to pressure being applied by an object to the keypad as one or more possible operating states of the keypad or the pushbutton. Within the scope of the invention, the multifunctional pushbutton can, depending on the design of the sensor device and its control device, recognize several different actuation states, which are selected, for example, from (i) touch or pressure force, (ii) approach or touch or pressure force, (iii) touch or low pressure force or strong pressure force, (iv) approach or touch or low pressure force or strong pressure force. The sensor device is preferably designed with its control device in such a way that it can detect at least three different actuation states of the push button.

With this embodiment variant, the positioning of the light guide and light decoupling for possible symbol lighting of the pushbutton is possible independently of the placement of the components of the sensor device and in a different plane than the components of the sensor device, as well as the great variability of the symbol lighting through the light decoupling elements within the cover. In principle, the one or more light decoupling elements can be arranged anywhere in the cover outside of the IR transmission area in the keypad, i.e. in particular outside of the keypad and also in the area of the IR reflection area of the keypad.

In one embodiment of the invention, the cover has a cover plate on its user side, which is at least partially (i.e. in its entirety or at least in the areas relevant to the sensor device or the symbol illumination) transparent to IR light and/or visible light, and on the side of this cover plate facing away from the user side a layer that is transparent to IR light and visible light.

In this configuration of the cover, the translucent layer of the cover can preferably be designed in the form of a light guide, which is provided with a reflector for reflecting IR light and visible light in the area outside the IR transmission range of the cover on the inside of the cover. In addition, the one or more light decoupling elements can preferably be placed in the light-transmitting layer or the light guide of the cover. In addition, one or more symbol elements can preferably be provided in or on the cover plate of the cover in the area or areas of the one or more light decoupling elements, which are then backlit by the visible light emitted by the light emitter and guided through the transparent layer or the light guide and decoupled by the light decoupling elements.

• 1 eine Draufsicht einer Drucktaste gemäß einem Ausführungsbeispiel der vorliegenden Erfindung;
• 2 eine Schnittansicht der Drucktaste von 1 gemäß einer nicht zur Erfindung gehörenden Ausführungsvariante; und
• 3 eine Schnittansicht der Drucktaste von 1 gemäß einer Ausführungsvariante der Erfindung.

The above and other features and advantages of the invention will be better understood from the following description of a preferred, non-limiting exemplary embodiment with reference to the accompanying drawings. In it show, mostly schematically:

• 1 12 is a top view of a push button according to an embodiment of the present invention;
• 2 a sectional view of the pushbutton of FIG 1 according to an alternative embodiment not belonging to the invention; and
• 3 a sectional view of the pushbutton of FIG 1 according to an embodiment variant of the invention.

1 until 3 show the structure and operation of a multifunctional push button according to an embodiment of the invention in different variants. Identical or corresponding components are identified by the same reference numbers. The sectional views of 2 and 3 each essentially correspond to a section line AA in 1 .

The multifunction push button 10 has a cover 12 that defines in portion a keypad 14 that can be operated by a user. The cover 12 is designed to be elastically deformable in the area of the keypad 14 so that the user can touch the keypad 14 to operate the pushbutton 10 and can press the keypad 14 in slightly with pressure.

As in 1 shown schematically, the cover 12 in the area of the keypad 14 has an IR transmission area 15 in which the cover 12 is transparent to IR light, and next to it an IR reflection area 16 in which the cover 12 reflects IR light.

The cover 12 has which, as in 2 and 3 shown, a user side facing away from a user 12a and a user facing away from the inside 12b and is composed of a cover plate 122 and a light-transmissive layer 124 and reflectors 126 . The cover plate 122 is arranged on the user side 12a and is permeable to IR light and visible light everywhere or at least at the respective relevant points. The cover plate 122 is made of glass, glass ceramic or plastic, for example. The transparent layer 124 is arranged on the side of the cover plate 122 facing away from the user side 12a and is in contact with the cover plate 122 . The transparent layer 124 is transparent to IR light and visible light. The reflectors 126 are attached to the light-transmitting layer 124 on the inside 12b, except in the region of the IR transmission region 15. The reflectors 126 reflect both IR light and visible light. The light-transmitting layer 124 together with the reflectors 126 forms a light guide for visible light in the cover 12. In the IR transmission area 15, the cover plate 122 of the cover 12 is IR-transmissive and only the cover plate 122 and the light-transmitting layer 124 are present. In the IR reflection area 16, the cover 12 has, in addition to its cover plate 122, the transparent layer 124 and a reflector 126.

A sensor device 18 is arranged on the inside 12b of the cover 12 . As in 1 until 3 As illustrated, the sensor device 18 has a transmitter 19 for emitting IR light. The transmitter 19 is positioned at a distance behind the cover 16 in the transition area between the IR transmission area 15 and the IR reflection area 16 and emits both IR light e1 in the direction of the IR transmission area 15 and IR light e2 in the direction of the IR reflection area 16, in which a reflector 126 is present on the inside 12b of the cover 12. The sensor device 18 also has a first receiver 20 in an area behind the cover 12 assigned to the IR transmission area 15 and a second receiver 21 in an area behind the cover 12 assigned to the IR reflection area 16 . A first IR barrier 23 is arranged between the transmitter 19 and the first receiver 20 in order to block a direct feed of the IR light e1 emitted by the transmitter 19 to the first receiver 20 . A second IR barrier 24 is arranged between the transmitter 19 and the second receiver 21 in order to block the IR light e2 emitted by the transmitter 19 from being fed directly to the second receiver 21 . The sensor device 18 also has a control device 25 which is coupled to the transmitter 19 and the first and second receivers 20, 21. The components of the sensor device 18 are mounted, for example, on a support plate (not shown) which is spaced behind the cover.

As in 2 and 3 As illustrated, the IR light e1 emitted by the transmitter 19 in the direction of the IR transmission range 15 passes through the cover 12 and can be reflected on an object 17 such as a finger of a user outside the cover 12 . The IR light r1 reflected by the object 17 again passes through the IR transmission range 15 of the cover 12 and hits the first receiver 20, with the detection location and/or the light intensity of the reflected IR light r1 on the first receiver 20 depending on the distance of the object 17 from the cover 12 and the first receiver 20. Based on the measurement signal from the first receiver 20, the control device 25 can then determine the distance and optionally also the change in distance between the object 17 and the first receiver 20, in order then, based on this determination result, to determine that the keypad 14 has been touched by the object 17 as an actuation state of the keypad 14. Optionally, the control device 25 in addition to determining that the keypad 14 has been touched, an approach of an object 17 to the keypad 14 can also be determined as another actuation state of the keypad 14 .

As also in 2 and 3 illustrated, the IR light e2 emitted by the transmitter 19 in the direction of the IR reflection area 16 strikes the reflector 126 on the inside 12b of the cover 12 and is reflected by the reflector 126 . The IR light r2 reflected by the reflector 126 then impinges on the second receiver 21 , the detection location of the reflected IR light r2 on the second receiver 21 depending on the distance between the cover 12 or its reflector 126 and the second receiver 21 . When a user presses the keypad 14, the cover 12 is slightly deformed in the area of the keypad 14 and is depressed toward the inner side 12b. This also changes the distance from the reflector 126 to the transmitter 19 and the second receiver 21 and, as a result, the detection location and/or the light intensity of the reflected IR light r2 on the second receiver 21. The control device 25 can then, based on the measurement signal from the second receiver 21, determine the distance and optionally also the change in distance between the cover 12 and the second receiver 21, in order then, based on this determination result, to determine whether the object 1 7 as an operation state of the keypad 14 to be determined. Optionally, the control device 25 can also determine different degrees of depression of the keypad 14 as different actuation states of the keypad 14 .

In addition to the sensor device 18 described, this multifunctional push button 10 also includes an icon lighting system to display icons for informational purposes to the user on the user side 12a of the cover with visible light. For example, the position and the function of the keypad 14 can be made clear to the user by such a symbol illumination.

As already mentioned, the cover 12 contains a light guide which is formed from the light-transmitting layer 124 and the reflectors 126 . This light guide is thus located within the cover 12 and can guide visible light in the direction of the cover 12 plane. In the embodiment of 2 a light emitter 26 for emitting visible light is also arranged in the cover 12 . The light emitter 26 is also placed within the light-transmissive layer 124 and emits the visible light o1 into the cover 12 in one or more directions toward the light guide 124, 126. In the light-transmissive layer 124, one or more light extraction elements 28 are also arranged. When the visible light o1 emitted by the light emitter 26 and guided through the light guide reaches a light extraction element 28, the visible light from the light guide is coupled out of the light-transmitting layer 124 towards the user side 12b of the cover 12 and is emitted out of the cover 12 through the cover plate 122 towards the user. The light decoupling elements 28 can optionally be positioned in all areas of the cover, except in the area of the IR transmission area 15 in the keypad 14 . Depending on the application and depending on the desired design of the symbol lighting, a symbol element 29 can be provided in/on the cover plate 122 of the cover 12 in the area of the light output elements 28, which is backlit by the output visible light o3.

The special advantages of this symbol illumination system are that the light guide 124, 126 and the light decoupling elements 28 are arranged in a different plane than the components of the sensor device 18 and the IR light e1 and the visible light o1, o2 can cross, which leads to a high degree of variability in the symbol illumination. The symbol lighting can be used, for example, in the representation of 1 be placed in the entire area of the cover 12 outside the keypad 14 or outside the IR transmission area 15 of the keypad 14.

In the second embodiment of 3 the symbol lighting differs from that of the first variant of embodiment 2 by the arrangement of the light emitter 26. The light emitter 26 is in the variant of 3 on the side of the inside 12b behind the cover 12 and emits the visible light o1 in the direction of the cover 12. So that the visible light o1 can penetrate into the light guide or the light-transmissive layer 124 of the cover 12, a recess 31 is provided in the reflector 126 in this area. So that the visible light o1 that has penetrated the translucent layer 124 can then be guided through the cover 12, a light deflector 30 is also placed in the penetration area, which deflects the penetrating visible light o1 in one or more directions into the light guide / reflects it to the side. The visible light o2 deflected in this way then flows through as in the variant of 2 the light guide of the cover 12 and reaches the one or more light decoupling elements 28. Otherwise, the variant of 3 that of 2 .

Reference List

10

push button

12

cover

12a

user page

12b

inside

122

cover plate

124

translucent layer

126

reflector

14

keypad

15

IR passband

16

IR reflection range

17

object

18

sensor device

19

Channel

20

first recipient

21

second recipient

23

first IR barrier

24

second IR barrier

25

control device

26

light emitter

28

light extraction element

29

symbol element

30

light deflector

31

recess

e1

emitted IR light in the direction of the IR transmission range

e2

emitted IR light in the direction of the IR reflection area

r1

IR light reflected from object

r2

IR light reflected by reflector

o1

emitted visible light

o2

redirected visible light

o3

extracted visible light

Claims (8)

Push button (10) comprising: a cover (12) with a user side (12a) facing a user and an inner side (12b) facing away from the user, the cover (10) defining a keypad (14), wherein the cover (12) is at least partially elastically deformable in the keypad (14), and wherein the cover (12) in the keypad (14) has an IR transmission area (15), in which the cover (12) is designed to be permeable to IR light, and an IR reflection area (16), in which the cover (12) is designed to be reflective to IR light; and a sensor device (18) arranged on the side of the inside (12b) of the cover (12) for detecting an actuation state of the keypad (14), wherein the sensor device (18) comprises: a transmitter (19) for emitting IR light (e1) in the direction of the IR transmission area (15) of the cover (12) and IR light (e2) in the direction of the IR reflection area (16) of the cover (12); a first receiver (20) for detecting an IR light (r1) reflected from an object (17) on the user side (12a) of the IR transmission range (15) of the cover (12); and a second receiver (21) for detecting an IR light (r2) reflected by the IR reflection area (16) of the cover (12), and further comprising: at least one light emitter (26) arranged on the inside (12b) side of the cover (12) for emitting visible light (o1) into the cover (12); at least one light deflector (30) arranged in the cover (12) for deflecting (o2) the visible light (o1) of the light emitter (26) in a direction parallel to the plane of the cover (12); and one or more light decoupling elements (28) arranged in the cover (12) for decoupling (o3) the visible light (o2) from the light deflector (30) from the user side (12a) of the cover (12). push button after claim 1 , in which the sensor device (18) also has a control device (25) which is designed to determine a distance or a change in distance from the object (17) to the first receiver (20) from the IR light (r1) detected by the first receiver (20) and to determine a distance or a change in distance from the cover (12) to the second receiver (21) from the IR light (r2) detected by the second receiver (21). push button after claim 2 , in which the control device (25) is further configured to detect a touch of the keypad (14) by an object (17) and/or an approach of an object (17) to the keypad (14) depending on the determined distance (change) from the object (17) to the first receiver (20). push button after claim 2 or 3 , in which the control device (25) is further configured to detect a deformation or a degree of deformation of the keypad (14) as a result of an object (17) applying pressure to the keypad (14), depending on the determined distance (change) from the cover (12) to the second receiver (21). A pushbutton according to any one of the preceding claims, wherein the cover (12) on its user side (12a) has a cover plate (122) which is at least partially permeable to IR light and/or visible light, and the cover (12) has a layer (124) which is permeable to IR light and visible light on the side of the cover plate (122) facing away from the user side (12a). push button after claim 5 , in which the light-permeable layer (124) of the cover (12) is designed in the form of a light guide, which is provided with a reflector (126) for reflecting IR light (e2) and visible light (o1, o2) in the area outside the IR transmission range (15) of the cover (12) on the inside (12b) of the cover (12). push button after claim 5 or 6 , wherein the one or more light extraction elements (28) are placed in the light-transmitting layer (124) of the cover (12). Push button after one of the Claims 5 until 7 , in which one or more symbol elements (29) are provided in or on the cover plate (122) of the cover (12) in the area or in the areas of the one or more light decoupling elements (28).

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