Stepless unlocking fixing device

A stepless unlocking fixing device, comprising

• a base comprising a bottom plate, two side plates, a receiving cavity surrounded by said bottom plate and said two side plates, a through hole provided in a middle of said bottom plate, and two buckles respectively provided on two opposite ends of said bottom plate;
• two levers of the same structure symmetrically pivotally connected between said two side plates of said base, said two levers being rotatable toward the center to unlock and rotatable toward two opposite sides to lock, each of said two levers comprising a cam portion received in said receiving cavity, an operating portion extended from said cam portion toward one respective said buckle, a contact portion and an arc surface formed on one side of said cam portion opposite to said operating portion, a first abutting portion formed on one side of said arc surface near said contact portion, and a second abutting portion formed on an opposite side of said arc surface away from said contact portion;
• and
• a support comprising a positioning plate, an abutting rod protruding upward from said positioning plate and being capable of extending into said through hole of said base and entering into said receiving cavity, a contact surface formed on a top side of said abutting rod, an interference portion with a relatively larger width formed on the periphery of said abutting rod at an upper side, and a locking portion with a relatively smaller width formed on the periphery of said abutting rod at a bottom of said interference portion;
• and
• wherein when said contact portion and said arc surface are kept away from said abutting rod, a fully unlocked state is formed;
• when said contact portion is in contact with said contact surface and said first abutting portion is in contact with said interference portion, a buffer unlocked state is formed;
• when said contact portion is in contact with said contact surface, said second abutting portion is in contact with said locking portion, and said operating portion and each said buckle are engaged and positioned, a fully locked state is formed.