EP3697177B1 - Tactile sensor with integrated light guide - Google Patents

Description

The invention is based on a push button sensor with a circuit board carrier for surface mounting, a circuit board mounted on the circuit board carrier on which at least one switching element and at least two light sources are arranged, and with at least one operating rocker for actuating the switching element, the operating rocker having at least one Has light guide, via which light generated by the light sources is guided to a control surface of the rocker switch. Such a push button sensor is from the DE 20 2008 015 052 U1 known. Other devices are known from EP 2 461 238 A2 , EP 1 005 055 A2 , EP 3 407 369 A1 such as US 2006/201796 A1 .

Such touch sensors often have several of the light guides described above, for example to indicate different switching states. White light diodes are sometimes used as light sources, which due to manufacturing tolerances, however, emit a light spectrum that varies from diode to diode, so that with the touch sensors known from the prior art there can be color differences between the spectrum of the light sources of the touch sensor, which is sufficient aesthetic reasons is undesirable. Furthermore, the touch sensors known from the prior art have the disadvantage that the color spectrum emitted by the light sources can only be varied to a limited extent. However, if, for example, an RGB diode is used as the light source instead of a white light diode, it is often impossible to generate satisfactory white light.

It is therefore the object of the invention to further develop a touch sensor of the type described at the outset in such a way that the light guided via the light guide to the control surface has, on the one hand, a precise and, on the other hand, an adjustable color spectrum.

This object is achieved by a touch sensor with the features of claim 1. The dependent claims each relate to advantageous embodiments of the invention.

Accordingly, it is provided that the light guide has a first light entry face and a second light entry face separated from the first light entry face, light generated by a first of the light sources being coupled into the light guide through the first light entry face, and light generated by a second of the light sources through the second light entry surface is coupled into the light guide, with a first reflector of the first light entry surface of the light guide and a second reflector in front of the second light entry surface for light coupling into the light guide, and each of the two reflectors being a reflective boundary wall of a separate light mixing chamber, the a first of the light sources generated light is coupled into a first of the two separate light mixing chambers and the light generated by a second of the light sources is coupled into a second of the two separate light mixing chambers, with between hen the circuit board and the at least one rocker switch, a rocker mount is arranged to which the at least one rocker switch is pivotably attached.

It is thereby achieved that light generated by the first light source via the first reflector and light generated by the second light source via the second reflector is coupled into the light guide.

By using a light guide that is designed for the coupling of at least two light sources, which can be designed as different light sources, it is possible on the one hand to expand the light spectrum that can be generated and, on the other hand, to precisely generate one via the light guide by mutually coordinating the light sources with one another To realize control surface guided spectrum of the mixed light of both light sources. The mixed light from both light sources can emerge on the control surface via a common light exit surface.

If, for example, the light source is an RGB diode, it is expedient for the light spectrum emitted by the RGB diode to be mixed before it enters the light guide in order to homogenize the spectrum. For this purpose, in addition to the reflector described above for coupling the diode light into the light guide via the light entry surface, the light mixing chamber can have further reflectors or light-mixing means, for example materials that scatter the light, such as reflective microparticles.

The light mixing chamber can enclose the light source, the light of which is coupled into the light mixing chamber, with an opening via which the light is coupled into the light mixing chamber, in particular radiated into it.

At least one of the light sources can have a plurality of partial light sources which differ from one another with regard to the spectrum of their respective emitted light. The light source can be an RGB diode, for example.

The two light entry surfaces can each be perpendicular to a light exit surface which is arranged in the operating surface of the rocker switch or at least parallel thereto.

Both the light coupled into the light guide via the first light entry surface and also the light coupled into the light guide via the second light entry surface can be coupled out of the light guide via the same light exit surface.

The light coupled into the light guide via the first light entry surface and the light coupled into the light guide via the second light entry surface can be decoupled from the light guide as mixed light after multiple reflections within the light guide.

A rocker mount, to which the at least one control rocker is pivotably attached, can be arranged between the board and the at least one operating rocker. The first and the second reflector and / or a respective light mixing chamber can each extend through the rocker mount up to the respectively assigned light source. It can be provided that at least one of the light sources protrudes into the respectively assigned light mixing chamber. Alternatively, the light source can be directly upstream of the light mixing chamber, in particular the opening of the light mixing chamber. A reflector of the light mixing chamber can be designed as a parabolic mirror, the light source being arranged at the focal point of the parabolic mirror.

The light guide can be arranged on the edge of the rocker switch and have a first light exit surface, which is arranged in the rocker control surface or at least parallel to it, and a second light exit surface, which is arranged perpendicular to the first light exit surface and on the outer circumference of the rocker switch.

The first and the second light exit surface can be formed in one piece and in particular merge without interruption at an edge of the rocker switch, thereby ensuring that the pushbutton sensor can be easily recognized in the dark, even from the side.

Starting from its outer circumference, the rocker switch can have a cutout, preferably a substantially U-shaped cutout, into which the light guide is inserted. A light exit surface of the light guide can in turn be arranged in the operating surface of the operating rocker or at least parallel thereto.

One of the two light sources can be a white light source, preferably a white light-emitting diode, and the other a light source with an adjustable emission spectrum, preferably an RGB light-emitting diode.

The light guide can consist of a plastic or glass with embedded reflective microparticles, at least in the beam path of the coupled light, in order to improve the mixing of the light spectra of the light sources.

Figur 1

eine beispielhafte Ausführungsform eines erfindungsgemäßen Tastsensors in einer Explosionsdarstellung;

Figur 2

eine beispielhafte Ausführungsform einer Bedienwippe eines erfindungsgemäßen Tastsensors in einer Explosionsdarstellung;

Figur 3

die Bedienwippe gemäß Figur 2 in perspektivischer Sicht auf die Unterseite der Bedienwippe;

Figur 4

eine Detailansicht eines Unterteils einer Bedienwippe gemäß einer Ausführungsform der Erfindung in perspektivischer Sicht auf die Unterseite des Unterteils;

Figur 5

die Ausführungsform gemäß Figur 4 in perspektivischer Sicht auf die Oberseite des Unterteils; und

Figur 6

eine teilangeschnittene Ansicht eines Unterteils sowie einer daran anliegenden Platine.

Further details of the invention are explained with reference to the following figures. It shows:

Figure 1

an exemplary embodiment of a touch sensor according to the invention in an exploded view;

Figure 2

an exemplary embodiment of a rocker switch of a touch sensor according to the invention in an exploded view;

Figure 3

the rocker switch according to Figure 2 in a perspective view of the underside of the rocker switch;

Figure 4

a detailed view of a lower part of a rocker switch according to an embodiment of the invention in a perspective view of the underside of the lower part;

Figure 5

the embodiment according to Figure 4 in a perspective view of the top of the lower part; and

Figure 6

a partially cut-away view of a lower part and a board attached to it.

The Figure 1 shows a first embodiment of a touch sensor 1 according to the invention. This has a circuit board carrier 2 for receiving a circuit board 3, the circuit board 3 having four arrangements of a switching element 4 and each associated with a first light source 5.1 and a second light source 5.2 on opposite longitudinal edges at regular intervals. The two light sources 5.1, 5.2 can differ in at least one property, in particular with regard to the light spectrum they emit. For example, the first light source 5.1 can be a white light LED, while the second light source 5.2 is an RGB LED. The arrangements, each comprising a switching element 4 and two light sources 5.1, 5.2, are arranged opposite one another in pairs. In total, eight of the previously described arrangements are provided on the circuit board 3 opposite one another in pairs, with four arrangements each on each of two opposite edges of the circuit board.

A rocker mount 14 covers the board 3, so that the board 3 is arranged between the board carrier 2 and the rocker mount 14. In addition to a pivot axis 24, about which the operating rockers 6 can be pivoted, the rocker carrier 14 has reset elements 23 opposite one another in relation to the pivot axis 24. The switching elements 4 can be operated individually by pivoting the operating rockers 6 about the pivot axis 24 via openings 27 through the rocker mount 14. The light emitted by the light sources 5.1, 5.2 can also are coupled through the openings 27 into the light guides 7 arranged in the rocker switches 6.

The rocker switch 6 is designed in four parts, therefore four rocker switches 6 that can be operated separately are provided; each of the four rocker switches 6 can be pivoted around the pivot axis 24 independently of the other rocker switches 6 in order to activate one of the switching elements 4 opposite in pairs.

The four-part rocker switch 6 has a light guide 7 on each of its four subsegments on opposite edges of the respective subsegment, via which light from respectively assigned light sources 5.1, 5.2 is guided to the control surface 8 of the rocker switch 6 and to the side edge of the rocker switch 6. The operating rockers 6 can therefore be clearly identified both in the front view and in the side view in the dark. Likewise, status information can be displayed about a light color or intensity of the light emitted via the light guide 7, for example about a switching status of an actuator of a building automation system.

In the Figure 2 an exemplary embodiment of a rocker switch 6 is shown. For example, it can be one of the four subsegments of the rocker switch 6 according to FIG Figure 1 act.

The rocker switch 6 consists essentially of a decorative part 25 which is fixed on a lower part 19 via an adhesion promoter 18, for example an adhesive film. The lower part 19 has a locking receptacle 21 in the center in the longitudinal direction for receiving a pivot axis, around which the operating rocker 6 for actuating the switching elements 4 (see Fig. Figure 1 ) is pivotable. At its opposite ends in the longitudinal direction, the lower part 19 has a receptacle 20 for receiving a light guide 7. The receptacles 20 are open towards the decorative part 25, so that when the decorative part 25 is fixed on the lower part 19, the light guides 7 are fixed in the receptacles 20.

The light guides 7 each have 2 light entry surfaces 9, one of which is used for coupling the light from one of the two light sources 5.1, 5.2 (see FIG. Figure 1 ) is provided. The light guide 7 also has a mounting web 22 over which the light guide 7 is locked in the receptacle 20. The light guide 7 also has a first light exit surface 13, which is aligned with the control surface 8 of the decorative part 25, and a second light exit surface 15, which is perpendicular to the first light exit surface 13 and is aligned with an outer circumference of the rocker switch 6. The two light exit surfaces 13, 15 merge into one another in one piece.

In the Figure 3 is the in Figure 2 Control rocker 6 shown from the rear. In this illustration, it can be seen in particular that a light mixing chamber 11 is located in front of each light guide 7 of each of the two light entry surfaces 9. The light mixing chamber 11 is provided to mix the light emitted by the light source 5, for example an RGB LED, which is respectively assigned to the light mixing chamber 11, before it is coupled into the light guide 7 via the light entry surface 9. This is particularly useful when the light source 5 is composed of several partial light sources, as is the case with an RGB LED, for example, due to the design. The light mixing chamber 11 thus serves to further homogenize the spectrum of the light coupled into the light guide. For example, a first of the two light mixing chambers 11 can be assigned an RGB LED, while the second light mixing chamber 11 is assigned a white light LED.

The rocker switch 6 has, at its opposite ends, a light guide 7, the respective light entry surfaces 9 of which are assigned to separate light mixing chambers 11. A separate light source is assigned to each of the light mixing chambers 11, wherein at least one of the light sources, as already mentioned, can in turn be a light source composed of several partial light sources, for example an RGB LED.

At its opposite ends, the lower part 19 has two locking pieces 26 associated with the light guides 7, by means of which the operating rocker 6 can be locked in the longitudinal direction of the operating rocker 6, with corresponding receptacles for the locking pieces 26 on the rocker mount 14 (see Fig. Figure 1 ) are designed in the manner of a slot in order to enable the rocker 6 to pivot about the pivot axis received in the latching receptacle 21.

In Figure 3 it can also be seen that when the light guide 7 is inserted into the decorative part 25, the first and second light exit surfaces 13, 15 are aligned with two outer sides of the decorative part 25 that are perpendicular to one another.

In the Figure 4 a detailed view of a lower part 19 with light guides 7 received therein is shown from the underside, that is to say with a view of the side which faces the rocker mount 14 when the rocker switch 6 is mounted on the rocker mount 14. It can again be seen that the light entry surfaces 9 of the light guide 7 are each enclosed by a light mixing chamber 11. The light mixing chamber 11 has a delimiting surface which is designed as a reflector 10. The light radiated into the light mixing chamber 11 is deflected by about 90 ° by the reflector and is coupled into the light guide 7 essentially perpendicular to the light entry surface 9.

At an end facing away from the light entry surfaces 9, the light guide 7 has the two light exit surfaces 13, 15, which are aligned perpendicular to one another and which, as has already been described by way of example with reference to the previous figures, each with an outer side of a decorative part 25 (see Figure 3 ) the rocker switch 6 can be aligned. The light mixing chamber 11 is accessible on one side via an opening 12, via which light can be radiated into the light mixing chamber 11 from a respective light source 5. The light mixing chamber 11 and in particular its reflector 10 can be designed to effectively couple directional light, such as is generated, for example, by a light-emitting diode, via the light entry surfaces 9 into the light guide 7, i.e. to deflect the light in the light mixing chamber 11 in such a way that it preferably strikes the light entry surfaces 9 essentially perpendicularly.

The Figure 5 shows the in Figure 4 The illustrated embodiment of a lower part 19 from the opposite side, that is to say from the side facing the decorative part 25. The receptacle 20, in which the light guide 7 is received in the lower part 19, is open on this side. Viewed from the end face of the lower part 19, the receptacle 20 is designed with an undercut, so that when the lower part 19 is glued to the decorative part 25, the light guide 7 is captively received in the receptacle 20. Latching pieces 26 are provided on the front side in order to lock the operating rocker 6 on the rocker receptacle 14 in the longitudinal direction of the operating rocker 6.

In the partially cropped illustration according to Figure 6 In particular, the geometry of the light mixing chamber 11 in relation to the light inlet surface 9 of the light guide 7 and the positioning of the illuminant 5.1 in relation to the light mixing chamber 11 are shown using an exemplary embodiment. If the lighting means 5.1 is a light-emitting diode, it radiates essentially perpendicularly into the light mixing chamber 11. A boundary wall 10 of the light mixing chamber 11 forms a reflector, via which the light radiated from the LED into the light mixing chamber 11 is coupled into the light guide 7 essentially perpendicular to the light entry surface 9. The reflector 10 can, for example, have the geometry of a parabolic mirror.

For each light guide 7, different light colors can be generated via the two light mixing chambers 11 assigned to the light guide 7, for example by assigning a white LED to a first of the two light mixing chambers 11, while the second light mixing chamber 11 is assigned an RGB LED. The LEDs radiate vertically upwards, each into the separate light mixing chamber 11 assigned to it. The light mixing chamber 11 mixes and homogenizes, in particular, the light from the RGB LED and reflects it into the light guide 7. The light guide 7 can for example consist of light-scattering material, whereby the color mixing is further improved. The light can be deflected to the light exit surface 13 by internal reflections. List of reference symbols 1 Touch sensor 25th Decor part 2 PCB carrier 26th Locking piece 3 circuit board 27 breakthrough 4th Switching element 5 Light source 5.1 first light source 5.2 second light source 6th Control rocker 7th Light guide 8th Control surface 9 Light entry surface 10 reflector 11 Light mixing chamber 12 opening 13 Light exit surface 14th Seesaw recording 15th Light exit surface 16 Edge 17th Cutout 18th Adhesion promoter 19th Lower part 20th admission 21st Snap recording 22nd Assembly bridge 23 Reset element 24 Swivel axis

Claims (12)

1. A Tactile sensor (1) with a circuit board support (2) for surface mounting, a circuit board (3) mounted on the circuit board support (2), on which at least one switching element (4) and at least two light sources (5.1, 5. 2) are arranged, and with at least one operating rocker (6) for actuating the switching element (4) at wherein the at least one operating rocker (6) has at least one light guide (7), via which light generated by the light sources (5.1, 5.2) is guided to an operating surface (8) of the operating rocker (6), characterized in that the light guide (7) has a first light entry surface (9) and a second light entry surface (9) separated from the first light entry surface (9), wherein light generated by a first of the light sources (5.1, 5.2) is coupled into the light guide (7) through the first light entrance surface (9), and wherein light generated by a second of the light sources (5.1, 5.2) is coupled into the light guide (7) through the second light entry surface (9), a first reflector (10) being mounted in front of the first light entry surface (9) of the light guide (7) and a second reflector (10) being mounted in front of the second light entry surface (9) for the light coupling into the light guide (7), and wherein each of the two reflectors (10) is a reflecting boundary wall of a separate light mixing chamber (11), wherein the light generated by a first of the light sources (5.1, 5.2) is coupled into a first of the two separate light mixing chambers (11) and the light generated by a second of the light sources (5.1, 5.2) is coupled into a second of the two separate light mixing chambers (11), wherein a rocker receiver (14) is arranged between the board (3) and the at least one operating rocker (6), to which receiver the at least one operating rocker (6) is pivotably attached.
2. The tactile sensor (1) according to claim 1, in which the light mixing chamber (11) encloses the light source whose light is coupled into the light mixing chamber (11) with an opening (12) via which the light is coupled into the light mixing chamber (11).
3. The tactile sensor (1) according to one of the preceding claims, in which at least one of the light sources (5.1, 5.2) has several partial light sources (5.1, 5.2) which differ from each other with respect to the spectrum of their respective emitted light.
4. The tactile sensor (1) according to claim 4, in which the two light entry surfaces (9) are each perpendicular to a first light exit surface (13) of the light guide (7), which is arranged in the operating surface (8) of the operating rocker (6) or at least parallel thereto.
5. The tactile sensor (1) according to one of the preceding claims, in which both the light coupled into the light guide (7) via the first light entry surface (9) and the light coupled into the light guide (7) via the second light entry surface (9) is coupled out of the light guide (7) via the same light exit surface (13).
6. The tactile sensor (1) according to claim 5, in which the light coupled into the light guide (7) via the first light entry surface (9) and the light coupled into the light guide (7) via the second light entry surface (9) is coupled out of the light guide (7) as mixed light after multiple reflection within the light guide (7).
7. The tactile sensor (1) according to one of the preceding claims, wherein the first and second reflectors (10) and/or a respective light mixing chamber (11) each extend through the rocker receptacle (14) to the respectively associated light source (5.1, 5.2).
8. The tactile sensor (1) according to claim 4, in which the light guide (7) is arranged at the edge of the operating rocker (6) and has the first light emission surface (13), which is arranged in the operating surface (8) of the operating rocker (6) or at least parallel thereto, and a second light emission surface (15), which is arranged perpendicular to the first light emission surface (13) and on the outer circumference of the operating rocker (6).
9. The tactile sensor (1) according to claim 8, in which the first and the second light-emitting surface (13, 15) are constructed in one piece and, in particular, merge into one another without interruption at an edge (16) of the operating rocker (6).
10. The tactile sensor (1) according to claim 1, in which the operating rocker (6), starting from its outer circumference, has a cutout (17), preferably a substantially U-shaped cutout, into which the light guide (7) is inserted, a light exit surface (13) of the light guide (7) being arranged in the operating surface (8) of the operating rocker (6) or at least parallel thereto.
11. The tactile sensor (1) according to one of the preceding claims, in which one of the two light sources (5.1, 5.2) is a white light source, preferably a white light emitting diode, and the other is a light source with an adjustable emission spectrum, preferably an RGB light emitting diode.
12. The tactile sensor (1) according to one of the preceding claims, in which the light guide (7) consists of a plastic or glass with embedded reflecting microparticles at least in the beam path.

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