HU209786B - Switching member having contactless indicator - Google Patents

Abstract

An electric switch device having a fixed base body (10) and an actuator key (7) that is arranged movably relative to said base body (10). A non-galvanically coupled indicator display (1) is arranged within the actuator key (7). Within the base body (10) a radiation source (4), preferably a light emitting diode (18) is provided for, which is actuated by coded pulses, and is coupled non-galvanically with a means (3) for converting radiation into electric signals, preferably with a photocell (19) that is arranged within the actuator key (7). Output voltage generated by said photocell (19) is applied both to a rectifier and to a processor unit (2) that are both arranged within the actuator key (7). The indicator display (1), preferably liquid crystal display (LCD) is activated by the processor unit (2) while the rectifier provides supply voltage both for the processor unit (2) and for the indicator display (1). Thus, the actuator key (7) is merely non-galvanically coupled with the fixed base body (10) and a large variety of symbols such as geometric patterns, characters and the like according to coded pulses imposed may be visually displayed by using one and the same indicator display (1).

Description

Scope of the description: 8 pages (including 4 pages)

EN 209,786

Technical area

The present invention relates to a switching element comprising a galvanic disconnected display having a properly fixed base body and a movable actuator relative thereto, the display being arranged in the actuator, a switching element between the actuating member and the base body.

Instruments, computer peripherals, typewriters, and many other similar devices use switches that indicate the purpose of the switch, the state of its operation, or indeed the need for operation on the switch itself, in its visible part, with different markings, figures, or alphanumeric characters. You may need to change these characters or characters for the same switch.

For example, spherical typewriters whose spherical heads are interchangeable are known and are thus suitable for writing different types of font, for example, Latin letters, Cyrillic letters, Greek letters, etc. In these cases, it is desirable to change the keyboard subtitle according to the font of each ball head placed.

It is often the case with computer peripherals that a dedicated keyboard is used, whose function can be changed by operating a separate button or switch. Depending on the different functions, different symbols must be used on the keyboard.

This includes, for example, switches used in electronic equipment, instruments, push buttons whose switching status should be indicated, and for example, a label corresponding to different modes should be displayed on the switch.

Previous Technique

Various modes of display on switches are known. The easiest way to light up is the light source integrated into the switch actuator, which is now practically solved with a light emitting diode (LED). This display mode is only for displaying two states, for example, to indicate the state of the switch or the state of need for operation.

For the above-mentioned spherical typewriters, the font change according to a known solution is to use a mask made of thin elastic material, in particular rubber, containing different fonts on the keyboard, which are placed on the keys of the keyboard. This solution is difficult to handle. Flexible rubber foil is a vulnerable material. Different masks should be stored. During long use, the elastic foil will age, wear and become unusable.

Alternatively, some of the keystrokes on the keyboard may use more than one signal, one of which is only one current. The same applies to multi-function push-button switches on pocket and desktop computers.

There are also several disadvantages. One disadvantage is that the size of the indicated symbol may be less. Another disadvantage is that you should usually note or pay attention to the actual one of the symbols used together. In this way, there is a risk of confusion.

There is no known solution for displaying different symbols on the visible surface of the switching element without the use of mechanical solutions, but with long-lasting, wear-resistant solutions.

Disclosure of the Invention

It is an object of the present invention to provide a switching element comprising a non-galvanic electronic display, displaying several symbols, characters or even short texts on the same display, with a long life and high reliability.

According to the invention, the switching element comprising the galvanic disconnected display described in the introduction to the object is achieved by means of a radial source in the base body and a means for converting radiation into an electric signal, a digital source connected to the source, a rectifier on the output of the radiation converting device and a rectifier on the other. a digital signal processing unit is connected, the signal processing unit output is connected to the display, and the signal processing unit and the display power connection are connected to the output of the rectifier.

According to a preferred embodiment of the coupling element according to the invention, the radiation source is made up of a light emitting diode and a device light element converting the radiation into an electrical signal.

A brief description of the drawings

Figure 1 shows a possible embodiment of a switching element according to the invention, in which the actuator is a sliding switch movable in a direction perpendicular to the plane of the drawing;

Figure 2 is a schematic view of the electrical structure of the slide switch shown in Figure 1, a

Figure 3 shows a more detailed circuit diagram of the electrical structure, while a

Fig. 4 is a diagram illustrating the operation of the switching arrangement of Fig. 3.

Embodiment of the Invention

In Figure 1, a switching element comprising a galvanic non-display display according to the invention is designed as a slide switch. The switch consists of an actuator 7 movable from a basic body 10 and a guide rail 8 formed on the basic body 10 in a direction perpendicular to the plane of the drawing. The base 10 is properly secured to the frame of the device or apparatus. The switch is actuated by the displacement of the actuator 7. Accordingly, several switching positions can be formed.

The base body 10 is provided with a radiation source 4, which may be primarily a light source, but may also be designed as a source of electric power or a magnetic field.

On the one hand, the actuator 7 generates the required switching, on the other hand, displays the characteristic data, signal, and diagram. The coupling is made such that the actuating member 7 on the lower half of the housing 9 has a 5

EN 209 786 Β is used to transmit radiation emitted by the radiation source 4. In the case of light radiation it can be a light guide known per se, a soft magnetic material in the case of magnetic radiation, and in the case of electrical radiation it is simply an electric conductive material. At the base body 10, a radial detector 6 is located further away from the source 4.

The switching is effected by the displacement of the actuating means 7 so that the signal transmitting element 5 is placed near the radiation source 4 and the radiation detector 6, so that a coupling between the radial source 4 and the radial detector 6 is generated and at the output of the beam sensor 6. a signal change occurs with which the circuit to be connected can be operated. The beam sensor 6 may use a photodiode, a phototransistor, a photoconductor or a photo resistor when a beam is applied. Of course, other light electric converters exist and can be used. For example, in the case of magnetic radiation, the beam sensor 6 may be an inductive coil or a Halo generator. When an electric field is used, the beam sensor 6 is an armor of a capacitor.

Of course, the coupling can also be created in a non-contacted manner, which is also known in many other embodiments, which are not described herein, as it is not the subject of the present invention.

The switch 7 actuator also has a galvanic-free display unit. The display 1 is positioned on the visible upper side of the housing 9 of the actuator 7 under a transparent cover plate 11.

The display 1 is preferably a liquid crystal display that is supported by a support plate 12 from below. The support plate 12, the display 1, and the topsheet 11 are attached to the housing 9, for example by gluing at the edge. The support plate 12, the display 1 and the topsheet 11 are held by a flange formed on the inner vertical wall of the housing 9.

There is an opening on the lower side of the housing 9 at the front of the source 4, in which a device 3 for converting radiation into an electrical signal is inserted. In the case of the application of the light beam of the device 3, it is a light element, the output of which emits a voltage when exposed to light. In the embodiment shown in FIG. 1, the converter 3 and the signal transducer 5 are arranged in such a way that the signal transmitting element 5 only covers the radiation to the device 3 on a small surface, so that most of the radiation is provided by the converter 3.

On the inner bottom side of the housing 9 there is a base plate 13 on which the device 3 is mounted on the one hand and on the other hand a signal processing unit 2 is mounted from above. This base plate 13 is preferably provided with printed wiring that connects the signal processing unit 2 with the converter 3, on the one hand, and the signal processing unit 2 via the wires 14 to the display 1 on the other.

Figure 2 shows a schematic view of the electrical structure of the switching element according to the invention. The source 4 is controlled by a source 17. The source 17 preferably generates digital signals which are encoded according to the symbol or character to be displayed. The same encoded pulses may be used to carry out the switching when the encoded pulses are transmitted to the radiation detector 6 via the transmitting element 5 during the operation of the switch. According to the different codes, the decoder (not shown) connected to the output of the radiation detector 6 can be used to create different switching states.

The output of the device 3, which converts the radiation into an electrical signal, is connected to a diode 15 and through that to a capacitor 16. The diode 15 and the capacitor 16 together form a rectifier. On the capacitor 16, the rectified voltage of the voltage pulses transmitted by the device 3 is displayed. In addition, the output of the device 3 is also connected to the input of the signal processing unit 2, which decodes the pulses and operates a display 1 connected to its output by displaying a character corresponding to that code.

The output of the rectifier, which is substantially connected to the two terminals of the capacitor 16, the signal processing unit 2, and the power supply terminals of the display 1. In this way, the power supply of the display 1 and the signal processing unit 2 can be covered by the radiated energy and it is not necessary to provide the voltage supply on a separate line.

Figure 3 shows a schematic diagram of the circuit arrangement shown in Figure 2, while the operation of the circuit can be tracked based on the signal patterns of Figure 4. In this embodiment, the source of radiation is a light emitting diode (LED) 18. Accordingly, the device for converting radiation into an electrical signal is realized with a light element 19. The output of the light element 19 is connected to the diode 15 and capacitor 16 on the one hand and the Schmitt trigger 20 on the input of the signal processing unit on the other hand. The signal processing unit 2 further includes a monofilament 21, a shift register 22, a display driver 23, and an oscillator 24. The Schmitt trigger output 20 connects to the monoflop input 21 on the one hand and the serial data input on the shift register 22 on the other. The inverter output of the monofilament 21 is connected to the clock input of the shift register 22.

The parallel outputs of the shift register 22 are connected to the data inputs of a display driver 23, known per se, in the present case a liquid crystal display drive. The display driver 23 also includes an oscillator 24, the output of which is connected to the input of the display driver oscillator 23. The outputs of the display driver 23 are connected to the inputs of the liquid crystal 1 in a known manner.

Operation of the switching arrangement of Figure 3 a

Figure 4 illustrates the shape of the signal. The light emitting diode 18 is provided with a coded impulse from a source not shown in FIG. 3, which emits X pulses accordingly. The light pulses X are distorted due to the limited transmission rate of the light emitting diode 18. The light pulses X, when reaching the light element 19, generate voltage pulses B thereof. The light element 19 further distorts the signal shape. The DC voltage applied to the capacitor 16 is displayed, which is the Schmitt trigger 20, monofilament 21, shift register 22, display driver 23, and oscillator 24

EN 209 786 B supply power. The voltage pulses B on the Schmitt trigger 20 are refreshed and outputs are substantially identical to the encoded impulses A, but with slightly delayed D pulses. The impulse edge of the pulses D starts the monofilament 21, the Q inverter output of which displays constant-time pulses E, which are placed on the clock input of the shift register 22.

From the comparison of the pulses E and D, it can be seen that the data present in the serial data input is entered into the shift register 22 on the rising edge of the pulses E. Thus, according to Fig. 4, the pulse D at the same time as the rising edge of the first pulse E is logically high, while the impulse D of the second pulse E is at a logical low level. Thus, the pulse width modulated encoded pulses A are already decoded into the shift register 22, which is decoded at the parallel outputs of the shift register 22 after the complete input of the serial code.

The circuit arrangement shown in Fig. 3 can, of course, be implemented in several embodiments. The switching itself can be constructed differently depending on the coding system. It is advisable to combine each circuit unit into a single integrated circuit. It does not affect the essence of the invention either when two or more light emitting diodes 18 are used, or, if the light element 19 is made up of a plurality of interlocked cells to achieve higher voltage. The diode 15 is preferably a low-voltage diode.

The switching element according to the invention is highly reliable since it does not contain a moving friction contact. At the same time, it is extremely versatile for multipurpose keyboards on pocket or desktop computers.

Claims (2)

PATENT CLAIMS A switching element comprising a galvanic offline display having a properly fixed base body and a movable actuator relative thereto, the display being disposed in the actuator, and a switching element between the actuator and the base body, characterized in that: ) a radiation source (4) and means (7) for converting the radiation into an electrical signal (3), a digital signal source (17) connected to the radiation source (4) and a digital signal processing unit for output of the radiation conversion device (3) (2) is connected, the display (1) is connected to the output of the signal processing unit (2) and the power connection of the signal processing unit (2) and the display (1) is connected to the output of the rectifier. An embodiment of a switching element according to claim 1, characterized in that the radiation source (4) consists of a light emitting diode (18) and the means (3) for converting the radiation into an electrical signal (19).