Keyboard with elevated keys

#1. Field of the Invention

#The present invention relates to a keyboard with elevated keys, and in particular to a keyboard with keys that can be elevated sequentially.

#2. Description of the Related Art

#The present invention can be more fully understood by reading the subsequent detailed description and examples with references made to the accompanying drawings, wherein:

#FIG. 1A is an exploded view of elevated keys of the conventional keyboard as referenced in the Prior Art;

#FIG. 1B is a schematic back view of a key cap of the elevated key in FIG. 1A;

#FIG. 3 is an exploded view of a keyboard with elevated keys of the invention. In order to simplify the drawing, FIG. 3 only shows a 3×3 array of the keyboard and an elevated key structure of the invention. In FIG. 3, the keyboard of the invention comprises a foundation sheet, a sliding member 30, a plurality of guiding sheets 20a-20c and a plurality of key sets (only one key is shown in FIG. 3).

#The foundation sheet includes a base sheet 15, a circuit membrane assembly 14 and an elastic sheet 13. The structure and assembly method are described in the Prior Art. Furthermore, the cap support 12 includes a first linking bracket 121 and a second linking bracket 122. The first linking bracket 121 of the cap support 12 can be pressed or released by the hooks 21 of the guiding sheet 20a to depress or elevate the key cap 11.

#In this embodiment, a whole guiding sheet in the Prior Art is divided into a plurality of guiding sheets 20a-20c. They are long narrow metal strips parallelly disposed on the foundation sheet to reduce both the friction force when moving. horizontally, and the thickness of the keyboard. Referring to the FIG. 3, the distances between the centerlines of the guiding sheets 20a-20c are equal to a first interval d. Using the guiding sheet 20a as an example, the guiding sheet 20a has three pairs of L-shaped hooks 21, three holes 23 and a Z-shaped track 24a. The holes 23 allow the elastic domes 131 on the elastic sheet 13 and the seats 151 and hooks 152 of the base sheet 15 to pass through. The hooks 21 are formed by punching and contacting. Each of the hooks 21 has a horizontal portion 211 and a vertical portion 212 and forms an inverted L-shaped hook. The hooks 21 contact the first linking bracket 121 to depress the key cap 11. That is the horizontal portions 211 of the hooks 21 start pressing the arms of the first linking bracket 121 when the guiding sheet 20a starts moving from a first position to a second position . The hooks 21 do not contact the cap support 12 when the guiding sheet 20a is in a first position, and the hooks 21 depress the cap support 12 to a depressed position when the guiding sheet 20a is in a second position. The total thickness of the keyboard is reduced because the key cap 11 is received in a depressed position.