Patent ID: 7240979

Claim:
An improving structure of adjustable sliding device that can be stretched and shortened in its length, comprising: a base, having a flat horizontal unit and two side plates which are formed perpendicularly to the flat horizontal unit, the flat horizontal unit is utilized for assembling to a pre-set horizontal surface, one of side plates is a vertical plate formed perpendicularly on one side of the flat horizontal unit and another side plate is a L-shaped plate formed perpendicularly on another side of the flat horizontal unit, wherein the L-shaped side plate comprises a horizontal plate and a perpendicular plate; a plurality of sliding devices, having two sliding units, an upper unit and a bottom unit, a slot is formed at a middle part of the upper unit and the bottom unit, a plurality of horizontal rotating units are located on the upper unit and the bottom unit, wherein the horizontal rotating units are located within the slot and are surrounded by protruding portions of the upper unit; an upper frame, having a horizontal unit and two side plates formed perpendicularly to both sides of the horizontal unit respectively, wherein one of the side plates is a perpendicular plate and another is a L-shaped plate, the L-shaped side plate comprises at least one horizontal side plate, a gap is formed in between one of the side plates and the horizontal plate of the L-shaped side plate for locating one sliding device; and at least one middle frame, having a horizontal unit and two side plates formed perpendicularly to both sides of the horizontal unit respectively, wherein one of the side plates comprises a perpendicular side plate and a horizontal side plate, a gap is formed in between one of the side plates and the horizontal side plate to locate one of sliding devices, the gap is utilized to engage the L-shaped side plate of the base into the middle frame, the horizontal plate of the L-shaped side plate of the base is assembled into the gap of the sliding device locating inside the middle frame, the sliding devices locating between the base and the middle frame to form corresponding assembled sliding structures that can slide smoothly against each other, the horizontal unit of the middle frame further comprising a L-shaped side plate having a perpendicular portion and horizontal portion, the L-shaped side plate is engaged into the gap of the upper frame, wherein the horizontal portion of the L-shaped side plate is engaged into the gap of the sliding device locating inside the upper frame, wherein the sliding devices locating inside the upper frame, the middle frame and the base are utilized to assembled between the upper frame, the base and the middle frame to form sliding assemblies.