Patent ID: 6491456
Filing Date: 2002-12-10
Classification: G06F,H01H

Abstract:
A key signal generating device for a keyboard, the keyboard comprising a base and at least one key structure that is moveable in an up and down direction, the key structure being fixed on the base, the key signal generating device set between the base and the key structure and comprising:a thin film circuit board set on the base to generate a key signal, and having a top surface, the thin film circuit board comprising a lower thin film circuit, an upper thin film circuit set above the lower thin film circuit, and a film set above the upper thin film circuit, the top surface of the thin film circuit board is the top surface of the film; at least one trench set on the top surface of the film; and at least one hollow rubber dome set on the thin film circuit board and extending out of the top surface of the thin film circuit board to provide elastic support for the key structure, the rubber dome having a predetermined space filled with air, one end of the trench extending to the predetermined space so that the predetermined space is in communication with the atmosphere; wherein when the key structure is pressed, the rubber dome is squeezed down by the key structure, causing air in the predetermined space to be released to the atmosphere through the trench.