Patent ID: 6971422

Claim:
A locking device for a plane machine comprising: a) a bottom base having: i) four posts, one of the four posts being connected to one of four corners of the base; and ii) a threaded rod connected to the bottom base at a first end thereof and having a rotating button fixedly connected to a second end thereof; b) a machine base having four rings, one of the four posts being inserted through each of the four rings, a center of the threaded rod being adjustably connected to a lateral side of the machine base; c) first and second rod bases, the first rod base being connected to a first end of the machine base, the second rod base being connected to a second end of the machine base; d) an actuating rod inserted through a shaft hole of each of the first and second rod bases and having an insert rod protruding upwardly from a first end thereof; e) an L-shaped handle pivotally connected at a first end thereof to a first end of the machine base and having a rectangular hole located on the first end, and a second end movable between unlocked and locked positions, the insert rod is inserted into the rectangular hole; and f) first and second side bases, the first side base is slidably connected to the first end of the machine base, the second side base is slidably connected to the second end of the machine base, each of the first and second side bases having two urging blocks located between and selectively engaging two posts of the four posts, wherein, when the second end L-shaped handle is in the unlocked position, the L-shaped handle moves the actuating rod and the first and second side bases toward the second end of the machine base, the two urging blocks of each of the first and second side bases are disengaged from the four posts, the machine base is adjustable upwardly and downwardly to a selected position by turning the threaded rod, and, when the second end L-shaped handle is in the locked position, the L-shaped handle moves the actuating rod and the first and second side bases toward the first end of the machine base, the two urging blocks of each of the first and second side bases are engaged with the four posts, the machine base is locked in the selected position.