Positioning device for a miter saw

A positioning device adapted for use in a miter saw, the miter saw including a base seat and a scale disc that is disposed on the base seat, and that is formed with a plurality of notches, said positioning device comprising:

• a working table including a main portion that is adapted to be disposed above and connected rotatably to the base seat, and a mounting portion that extends in an extending direction from a side periphery of said main portion;
• an elastic member having
• a fixing portion that is connected fixedly to said mounting portion of said working table,
• a movable portion that is opposite to said fixing portion and that is adapted to be adjacent to the scale disc, and
• a protruding portion that is connected to said movable portion, and that is adapted to downwardly move to removably engage one of the notches of the scale disc;
• and
• a lever member disposed in said mounting portion of said working table, and having
• a linking portion that is connected to said movable portion of said elastic member, and
• a handle portion that is opposite to said linking portion, said handle portion of said lever member being movable to convert said elastic member from a locking state for engaging said protruding portion of said elastic member with the one of the notches so that said working table is non-rotatable relative to the base seat, to a releasing state for moving said movable portion of said elastic member away from the scale disc so that said protruding portion is disengaged from the one of the notches to permit rotation of said working table relative to the base seat;
• wherein said positioning device further comprises a slide block unit including a slide block, said slide block being disposed slidably on said handle portion of said lever member, and being engageable with said mounting portion of said working table;
• wherein when said elastic member is in the locking state, said slide block is disposed at a non-engaging position that is distal from said elastic member;
• wherein said slide block is operable to move said handle portion of said lever member downwardly, such that said movable portion of said elastic member is moved upwardly to convert said elastic member from the locking state to the releasing state;
• and
• wherein when said elastic member is in the releasing state, said slide block is slidable toward said elastic member to an engaging position to engage said mounting portion of said working table, thereby securing the position of said handle portion of said lever member relative to said mounting portion of said working table and thereby maintaining said elastic member at the releasing state.