Long strip shape, welding points generally have six, double-pole double-throw, the middle two welding points are the input end, the outer four welding points are the output end; there are two sets of independent single-pole double-throw switch, two sets of synchronous action. After pushing, the middle input end and the distal solder joint are turned on, and then pushed back to bounce back, and the middle input end and the near end solder joint are turned on. The structural diagram of the key switch is mainly composed of a button assembly, a sliding mechanism and a contact switch group. Each button assembly includes a button, a key lever, a button return spring, and the like. The middle part of the key bar has a convex beam which is pressed against a trapezoidal insulating block, and one end of the key bar is pressed against the inclined surface of the sliding bar, and the lower part of the key bar is sleeved on the return spring. When a certain button is pressed, the key lever drives the trapezoidal insulation block to move downward, and the lateral contact switch spring is pushed by the insulating block to close it.

The skateboard mechanism is composed of a slide plate, a slide return spring, a gear lock block and the like. There is a tenon at each of the key bars, with a bevel on top and a groove on the bottom. The beam of the key bar is pressed against the inclined surface. When the key bar moves down, the beam presses the inclined surface to move the sliding plate sideways. When moving to the beam falling into the tenon groove, the slide is reset by the slide return spring, and the tenon locks the key to maintain the contact closure. At this time, if the second button is pressed, the slide plate is moved by its cross beam, and the first button is bounced (reset) by the button return spring, and the electrical contact is disconnected. The second button is moved down so that the corresponding contact is closed and the slider locks the key. In order to avoid short circuit of the two buttons pressed at the same time, the key switch is also provided with a gear lock block, which has a trapezoidal shape and is disposed in the horizontal slot of the skateboard between the adjacent two key bars. If the two-key lever is pressed at the same time, since the width of the gear lock block is slightly larger than the distance between the centers of the two key bars, the beam of the two-key bar is blocked at the same time and cannot be moved downward. The position of the contact switch group is inside the plastic housing of the key switch. Each contact switch consists of a moving contact and a stationary contact. Three static contacts are connected together, and three movable contacts are respectively riveted on three strip springs. When the key lever is moved down, the movable contact spring is pushed by the trapezoidal plastic insulating raft under the beam beam to close the static contact. When the key lever is raised, the dynamic and static contacts are separated due to the elasticity of the reed, and the switch is disconnected.