The invention relates to a device (2) for detecting manipulation on an object comprising an actuating switch (22) which has a snap-action disk (220) which can be switched between a first position and a second position, and an actuating element (21) which has a body (210) and an actuating stud (211), projecting from the body of the actuating element (21), for acting on the snap-action disk (220), wherein the actuating stud (211) has a first stiffness. According to the invention a contact element (213), arranged on the actuating stud (211), acts on the snap-action disk (220), wherein the contact element (213) has a second stiffness which is greater than the first stiffness.

A circuit interrupter includes a stationary contact and a moveable contact disposed on a moveable contact arm, the moveable contact being configured to be pivotable into and out of physical contact with the stationary contact by pivoting of the moveable contact arm about an axis. The moveable contact arm defines a pivot angle with respect to the stationary contact as the moveable contact arm pivots about the axis. A biasing member exerts a biasing force on the moveable contact arm which pivotally biases the moveable contact toward the stationary contact when the pivot angle is less than a zero-bias angle and which pivotally biases the moveable contact away from the stationary contact when the pivot angle is greater than a zero-bias angle.

The invention relates to a device (2) for detecting manipulation on an object comprising an actuating switch (22) which has a snap-action disk (220) which can be switched between a first position and a second position, and an actuating element (21) which has a body (210) and an actuating stud (211), projecting from the body of the actuating element (21), for acting on the snap-action disk (220), wherein the actuating stud (211) has a first stiffness. According to the invention a contact element (213), arranged on the actuating stud (211), acts on the snap-action disk (220), wherein the contact element (213) has a second stiffness which is greater than the first stiffness.

The present invention provides an illuminated keyboard, including a plurality of keys, a metal plate, a thin film circuit board, and a backlight module. The metal plate includes a plurality of metal domes, disposed below the keys, and correspondingly located above a plurality of electrical contact parts of the thin film circuit board. When a user presses each of the keys downward, the metal dome properly moves downward to get in contact with the corresponding electrical contact part to conduct the electrical contact part and generate a corresponding key signal. The backlight module is disposed below the thin film circuit board, and a plurality of light beams emitted from the backlight module is projected to the keys.

The present invention provides an illuminated keyboard, including a plurality of keys, a metal plate, a thin film circuit board, and a backlight module. The metal plate includes a plurality of metal domes, disposed below the keys, and correspondingly located above a plurality of electrical contact parts of the thin film circuit board. When a user presses each of the keys downward, the metal dome properly moves downward to get in contact with the corresponding electrical contact part to conduct the electrical contact part and generate a corresponding key signal. The backlight module is disposed below the thin film circuit board, and a plurality of light beams emitted from the backlight module is projected to the keys