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KEYBOARD TYPES The main types of flat keyboards more usually manufactured by IngTec, are classified accordingly to two main criteria, the first one is referered to the mechanical structure of the keyboard , and the second to the type of pushbutton used. It´s also possible the combination of any kind of stucture with any type of pushbutton.
A flat keyboard is classified as a sandwich keyboard, because the profile is uniform and the thickness is to be found between 0,6 and 1,4 mm. Everyone of the components in the keyboard are bond together forming a sandwich with minimun thickness and weigh.
The materials used in these type o keyboards are:
The low profile keyboards are one of the most complete entry data systems , because due to its structure, in the same system can be integrated short travel switches, piezoelectric switches, leds, displays or any electronic component needed for the interconexion to the data adquisition system. The final product is a complete and compact system, that has all of the advantages of a membrane switch, in terms of design and versatility. However the whole keyboard can be unmounted, to replace failing components.
The components utilized in these short of keyboard are:
Accordingly to the type of pushbutton INGTEC classifieds low profile keyboards in three groups: membrane siwtches, sensitive keyboards and short travel switches keybaord.
In this short of keyboard, the switches are metallic membranes. When these membranes are pressed a tactile response is produced to confirm he key actuation The main advantage of metallic membranes is the minimal thicknees of the keyhboard. The main characteristics of metallic membranes are:
In this type of keyborads En estos teclados no existen mecanismos pulsadores sobre los que ejercer una presión. Las teclas pasan a la posición de cierre simplemente al apoyar el dedo sobre ellas, ejerciendo una presión mínima. Este tipo de teclado reúne las siguientes ventajas indiscutibles:
Las principales aplicaciones de este tipo de teclado se encuentran en los equipos de electromedicina, puntos de venta, prototipos, y en general en sistemas donde el espesor ha de ser mínimo.
Short-travel keyswitches have major application in those systems in which are required very good mechanic and electrical characteristics, and the use of the keyboard is really intense. MAjor advantages of this keyboads are:
Los teclados antivandálicos tienen su principal aplicación en aquellos sistemas que están expuestos a la intemperie o simplemente en sistemas de uso publico, como pueden ser cajeros automáticos, cabinas telefónicas, o terminales de información o de acceso a Internet. Construidos con componentes metálicos en su mayoría, están protegidos contra descargas eléctricas, contra el polvo, y contra las salpicaduras de agua.
PIEZOELECTRICS
KEYBOARD These keyboards are based on the piezolectric effect. When a mechanic pressure is applied on a piezoelectric material, electrical charges are generated on the surface, because of the dielectric displacement, herein a electrical filed is generated. If both electrodes are applied to the piezoelectrical material, this electrical field can be transformed in an electrical voltage. In keyswitches based on dielectric effect, the electrical voltage can be amplified and conditioned to produce a short electrical impulse, which is high enough used to produce the actuation of a momentary switch. Keyboards based on this short os switches are usually installed in security systems, and industrial environments.
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