Break-resistant electric remote control

Abstract

A remote control for operating an electronic device comprising a plastic housing with a plastic plate segment with a control panel which has at least one control element, preferably button elements and/or at least one directional pad for operating an electronic device,

wherein the plastic plate segment is formed from a plastic material which has an Charpy impact strength of more than 6 kJ/m.sup.2, in particular of 9.0 kJ/m.sup.2+/−0.3 kJ/m.sup.2, wherein the plastic material is an isosorbide-based polymer.

Claims

1. A break-resistant electric remote control (1) for operating an electronic device comprising a plastic housing (2) with a plastic plate segment (15) with a control panel which has at least one control element, preferably button elements (6, 9-12) and/or at least one directional pad (8) for operating an electronic device, wherein the plastic plate segment (15) is formed from a plastic material which has an Charpy impact strength, in particular in the case of a notched specimen, of more than 6 kJ/m.sup.2, in particular of 9.0 kJ/m.sup.2+/−0.3 kJ/m.sup.2, wherein the plastic material is formed as an at least partially isosorbide-based polymer.

2. The remote control according to claim 1, wherein the plastic plate segment (15) has a higher resistance to sweat than ABS (acrylonitrile butadiene styrene).

3. The remote control according to claim 2, wherein the plastic material is executed as an isosorbide-based thermoplastic, in particular as a polycarbonate.

4. The remote control according to claim 3, wherein the plastic material has an elongation at break of more than 65%, in particular between 70-130% and/or a flexural modulus of more than 1700 MPa.

5. The remote control according to claim 4, wherein the plastic housing (2) comprises at least an upper shell (3) and a lower shell (4), and is particularly formed monolithically therefrom, the upper shell (3) and the lower shell (4) being formed from the plastic material.

6. The remote control according to claim 5, wherein individual control elements, preferably all control elements, are part of the plastic plate segment (15) in such a way that the plastic plate segment (15) is monolithic.

7. The remote control according to claim 6, wherein the control panel has at least two different surface roughnesses, with one or preferably all of the control elements having a first surface roughness and the intermediate areas (14) between the control elements having a second surface roughness.

8. The remote control according to claim 7, wherein the plastic material has a colouring for laser-marking of the material.

9. The remote control according to claim 8, wherein the remote control comprises a lower shell (4) of ABS material or a bisphenol-based polycarbonate material or the at least partially isosorbide-based polymer.

10. The remote control according to claim 9, wherein the lower shell (4) has a transparent sensor window, in particular a diode window, for emitting an optical sensor signal, wherein the sensor window is made of ABS material or an bisphenol-based polycarbonate material or the at least partially isosorbide-based polymer.

11. The remote control according to claim 10, wherein the remote control comprises an upper shell (3), which is made from the at least partially isosorbide-based polymer.

12. The remote control according to claim 11, wherein at least the control element(s) or the intermediate areas (14) have a high-gloss appearance.

13. The remote control according to claim 12, wherein the plastic plate segment (15) has plug-in elements (16) on the side opposite the control panel.

14. The remote control according to claim 1, wherein the plastic material is executed as an isosorbide-based thermoplastic, in particular as a polycarbonate.

15. The remote control according to claim 1, wherein the plastic material has an elongation at break of more than 65%, in particular between 70-130% and/or a flexural modulus of more than 1700 MPa.

16. The remote control according to claim 1, wherein the plastic housing (2) comprises at least an upper shell (3) and a lower shell (4), and is particularly preferably formed monolithically therefrom, the upper shell (3) and the lower shell (4) being formed from the plastic material.

17. The remote control according to claim 1, wherein individual control elements, preferably all control elements, are part of the plastic plate segment (15) in such a way that the plastic plate segment (15) is monolithic.

18. The remote control according to claim 1, wherein the plastic material has a colouring for laser-marking of the material.

19. The remote control-according to claim 1, wherein the remote control comprises a lower shell (4) of ABS material or a bisphenol-based polycarbonate material or the at least partially isosorbide-based polymer.

20. The remote control according to claim 10, wherein the remote control comprises an upper shell (3), which is made from the at least partially isosorbide-based polymer.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0033] The above-described properties, features and advantages of this invention, as well as the manner in which they are achieved, will become clearer in connection with the following description of the embodiments, which are explained in more detail in connection with the drawing, in which:

[0034] FIG. 1 is a perspective view of the control panel of the remote control, and

[0035] FIG. 2 is the perspective rear view of the upper shell of the remote control; and

[0036] FIG. 3 is a schematic illustration of a measuring arrangement for determining the long-term effects of sweat on the plastic surfaces of an isosorbide-based material in comparison with ABS.

LIST OF REFERENCE SIGNS

[0037] 1 Remote control, 2 Plastic housing, 3 Upper shell, 4 Lower shell, 5 Keypads, 6 Button element, 8 Directional pad, 9 Button elements, 10 Button elements, 11 Button elements, 12 Button element, 13 Confirmation key, 14 Intermediate areas, 15 Plastic plate segment, 16 Plug-in elements

DETAILED DESCRIPTION

[0038] The figure is a purely schematic representation. Actual geometric relations may deviate from the figure. Reference is made to FIG. 1, which shows a remote control 1 to control an electronic device (not shown in further detail), such as a multimedia device, in a perspective view.

[0039] The remote control 1 comprises a plastic housing 2 consisting of a first housing part in the form of an upper shell 3 and a second housing part in the form of a lower shell 4, as well as two keypads 5 having a plurality of button elements 6. For the sake of clarity, not all of the button elements 6 in the keypad 5 are provided with reference signs in the drawings. A directional pad 8 is arranged between the two keypads 5, comprising a first button element 9, a second button element 10, a third button key element 11, and a fourth button element 12.

[0040] The four button elements 9 to 12 are arranged circumferentially and at a distance of 90° from one another around a confirmation key 13. The directional pad 8 having the four button elements 9 to 12 is designed as circular disc in this case. The remote control 1 also comprises feedback elements 14 in the form of small lights which can light up when a button is pressed on the remote control 1. The remote control 1 is used as an example to explain the operation of a multimedia device. To this end, a user uses the buttons 5 on the upper shell 3 of the remote control 1 to enter control commands into the remote control 1 in the form of data which is then transmitted to the electronic device to be controlled via a transmitter (not shown in further detail). Such a command can be entered, for example, as a direction command via the button elements 9 to 12, which command then controls the movement of a control element on the exemplary multimedia device in one of the four possible directions of movement.

[0041] The button elements 6 of the respective keypads, individual button elements 9-12 and also the directional pad 8 may protrude with respect to the intermediate areas 14 between the button elements, e.g. the button elements 6, or may alternatively be recessed with respect to the intermediate areas 14. The button elements 6 and the intermediate areas can merge into each other without gaps so that the upper shell forms a continuous, preferably monolithic, control surface. The finger position and thus the assignment on the button elements 6 can be sensed, for example capacitively. The button elements 6, 9-12, the keypads 5, the directional pad 8 and all other components on the control surface are arranged on a plastic plate segment 15, which is also continuous, preferably monolithic, and which is part of the upper shell 3. The average thickness of the plastic plate segment 15 is less than 3 mm, preferably less than 1.5 mm.

[0042] The plastic housing 2 can be manufactured, for example, by injection moulding. Individual or all button elements 6, 9-12 or also the directional pad 6 have a surface which has a different surface roughness compared to the adjacent intermediate areas 14. There is thus a first and a second surface roughness on the control surface of the upper shell 3, the second surface roughness being greater than the first surface roughness. In addition to an improved visual perception of the button elements and a more intuitive and thus faster operation, the differentiation of the surface roughness also enables a better operation in the dark. It is quite common and necessary to switch on a television in the dark and operate it in low light. The differentiated surface roughness enables the correct buttons to be felt, especially when the layout of the keypad is known.

[0043] A special feature of the upper shell 3 is its particularly high Charpy impact strength which, in the case of a notched specimen, is more than 6 kJ/m.sup.2, in particular between 8.8 and 9.2 kJ/m.sup.2 according to ISO 179-1eU in the current version as of September 2021 at 23° C., x mm. In the case of an unnotched specimen, the impact is without breakage due to the pronounced ductility or pliability of the material.

[0044] A further advantage is an elongation at break of the material of the upper shell 3 of more than 65%, in particular between 70-130%, according to ISO 527-1, -2 in the current version as of September 2021 at 50 mm/min.

[0045] This reduces the tendency to breakage in the event of mechanical shock, to an extent that frequently occurs in the household.

[0046] At the same time, the material of the upper shell 3 has a flexural modulus of more than 1700 MPa at 23° C., preferably between 1900-2300 MPa, according to ISO 527 in the current version as of September 2021.

[0047] This means that the material is not brittle, but in addition to its strength also has a corresponding degree of flexibility under the so-called three-point load.

[0048] Remote controls should also be visually appealing and easy to clean, especially with little use of solvents. The present plastic housing is advantageously resistant to ethanol, the most common organic solvent used in cleaning agents. An attractive appearance of the upper shell 3 is achieved by using a material with a light transmittance of more than 90%, according to ISO 13468-1,-2 at 3 mm.

[0049] Another preferred property is the resistance of the upper shell 3 to fatty acids. It is known that the human body has a fatty layer. In the frequent handling of remote controls, fatty acids have an influence on the material of the plastic housing. Fatty acids can be found in hand creams, but also in snacks such as crisps or the like.

[0050] In many common remote controls, a common polycarbonate is used as the hard plastic component, which becomes cloudy and loses its gloss under the influence of fatty acids. This is not the case with the material within the scope of the present invention. Conversely, matt surfaces can increasingly acquire a greasy sheen under the influence of fatty acids.

[0051] At least the button elements and/or the intermediate areas preferably have a high-gloss appearance. This can be realised, for example, by a highly polished surface within the injection mould or by a post-processing, e.g. by the step of precision glass moulding. A high-gloss appearance in the context of the present invention enables a light source, e.g. an LED light strip with distinguishable individual light sources, to be reflected on the surface in such a way that the light sources can also be distinguished in the mirror image of the remote control surface. This high-gloss appearance corresponds to the surface with the aforementioned first surface roughness. In contrast, the second surface roughness is designed in such a way that no reflection and possibly only a slight reflection of light emanates from the surfaces with this second surface roughness.

[0052] All these boundary conditions, which are of particular advantage for a remote control, can be achieved by using an isosorbide-based polymer.

[0053] Particularly preferably, an isosorbide-based thermoplastic, in particular polycarbonate, is used to manufacture the control panel of the upper shell 3. A further advantage is that a sensory detection of the finger position is also possible without the material of the control panel interfering too strongly with the sensor signal.

[0054] Particularly preferably, the entire upper shell 3 or the entire remote control is made of the aforementioned material.

[0055] The material can have a dye and thus be coloured in a colour, e.g. black, white or similar. It is advantageous if the remote control 1 has a transparent signal window in addition to the coloured area for transmitting an optical signal. This signal window can also be made of the aforementioned material. Due to its excellent transmission values and with a preferred refractive index between 1.49-1.53, a good transmission of an optical signal from or to a terminal device can take place.

[0056] A particular further advantage is the reduction of the ecological footprint, since isosorbides of sufficient quality for further processing into the plastic material of the plastic housing 2 can be obtained from biological, in particular vegetable, starting materials such as D-sorbitol. The D-sorbitol can be converted into isosorbide by dehydration and ultimately into polycarbonate by polymerisation (melt polymerisation).

[0057] Individual components, in particular the upper shell and the lower shell, can have plug-in elements, pins and/or plug-in sockets, for connection to each other and/or to electronic components, in particular to a printed circuit board. The pins preferably have a diameter of less than 2 mm. The same applies to the wall thickness of the sockets. Despite their small contact surface with the plastic plate 15, which is located on the side of the plastic plate segment 15 opposite the operating surface, these filigree plug-in elements 16 have an excellent resistance to buckling in the event of oblique forces acting on them.

[0058] The plug-in elements 16 are shown as pins and/or sockets in FIG. 2.

[0059] FIG. 3 discloses a measuring sequence for simulating hand abrasion. For this purpose, the Tribotouch 101 abrasion tester is used to simulate hand abrasion. The test is carried out in accordance with the European standard DIN EN 60068-2-70/IEC 68-2-70.

[0060] The aim is to expose the surface to be tested to a hand operation that is as realistic as possible. In addition to the mechanical load, the chemical environment is also simulated with artificial sweat 102.

[0061] A test stamp 103 defined in the standard will strike the surface of the test specimen 104 at an angle of 45° and travel a straight friction path of 1 . . . 4 mm. There must be a special friction fabric between the test stamp and the test specimen. In addition, the friction fabric is wetted with a test substance.

[0062] Friction path: 4 mm, test frequency: 2 Hz, test substance: artificial sweat, fabric feed every 10,000 cycles 10 mm, fluid feed every 1000 cycles 1 ml, severity 1 N, 5 N, and 10 N.

[0063] The load with 1 N takes a very long time, so it was decided to use 5 N and 10 N to make the comparison.

[0064] ABS material (acrylonitrile butadiene styrene) and polycarbonate made from isosorbide or polyisosorbide carbonate were tested.

[0065] The test was carried out by visually comparing the surfaces.

[0066] The polycarbonate material shows a significantly higher degree of stress-and thus a higher resilience-during simulated button presses with artificial sweat than the ABS used as standard.

[0067] Thus, it could be proven that the sweat resistance of the new material as an important factor for the housing material of a remote control is significantly higher than that of ABS. Artificial sweat in particular can be used for this purpose. The temperature is room temperature at 25° C. A lack of resistance is to be understood as a dissolving of the plastic and the associated loss of gloss of the plastic surface after removal of the sweat. ABS as the reference substance is dissolved to a greater extent and earlier than the isosorbide-based plastic.