L-shaped key device

An L-shaped key device comprising:

• a base plate being elongated in a lengthwise direction and including a plurality of first hooks, two second hooks, and two third hooks;
• a thin film circuit board being elongated in the lengthwise direction and disposed on said base plate;
• a resilient member disposed on a top film surface of said thin film circuit board that is opposite to said base plate, and extending upwardly;
• a keycap disposed on a top end of said resilient member, and having
• a keycap body plate that is L-shaped and that has a plate bottom surface facing said thin film circuit board,
• a surrounding wall that extends downwardly from a periphery of said keycap body plate, and that has
• a first end portion and a second end portion spaced apart from each other in the lengthwise direction,
• a stepped side portion interconnecting said first end portion and said second end portion, and having a first segment and a second segment that are respectively adjacent to said first end portion and said second end portion, and
• a straight side portion spaced apart from said stepped side portion and interconnecting said first end portion and said second end portion, a distance between said first segment and said straight side portion in a direction transverse to the lengthwise direction being greater than a distance between said second segment and said straight side portion in the direction transverse to the lengthwise direction,
• a plurality of first pivotal seats that are disposed on said plate bottom surface of said keycap body plate, and that are adjacent to said straight side portion of said surrounding wall,
• two second pivotal seats that are disposed on said plate bottom surface of said keycap body plate, and that are adjacent to said first segment of said surrounding wall, and
• two third pivotal seats that are disposed on said plate bottom surface of said keycap body plate, and that are adjacent to said second segment of said surrounding wall;
• and
• a scissor mechanism disposed between said base plate and said keycap, and including
• a first linkage member that is elongated in the lengthwise direction and that has
• a first linkage body having a main top surface, a main bottom surface that is opposite to said main top surface, a first hook-engaging rod that is connected to said main top surface and said main bottom surface and that is pivotally engaged with said plurality of first hooks, and a first seat-engaging rod that is connected to said main top surface and said main bottom surface and that is pivotally engaged with said plurality of first pivotal seats,
• a central hole extending through said main top surface and said main bottom surface of said first linkage body, said resilient member extending through said central hole,
• a first hole extending through said main top surface and said main bottom surface of said first linkage body and disposed on a side of said central hole,
• a second hole extending through said main top surface and said main bottom surface of said first linkage body and disposed on an opposite side of said central hole,
• two first linkage pivotal notches being in spatial communication with said first hole, and aligned with each other along a first axis that extends in the lengthwise direction, and
• two second linkage pivotal notches being in spatial communication with said second hole, and aligned with each other along a second axis that extends in the lengthwise direction and that is parallel to the first axis,
• a second linkage member that is disposed in said first hole, that is rotatable about the first axis, that is T-shaped, and that has
• a first linkage part having a second seat-engaging rod that is pivotally connected to said two second pivotal seats of said keycap,
• a second linkage part having a second hook-engaging rod that is pivotally connected to said two second hooks of said base plate, a maximum length of said first linkage part in the lengthwise direction being greater than a maximum length of said second linkage part in the lengthwise direction, and
• two first pivotal shafts disposed on said second linkage part and respectively inserted into said first linkage pivotal notches, and
• a third linkage member that is disposed in said second hole, that is rotatable about the second axis, and that has
• a third seat-engaging rod pivotally connected to said two third pivotal seats of said keycap,
• a third hook-engaging rod pivotally connected to said two third hooks of said base plate, and
• two second pivotal shafts respectively inserted into said second linkage pivotal notches.