Patent ID: 6840009

Claim:
A sliding window structure suitable for fitting in a window opening, the window structure comprising: two moveable casements moveable in vertical guiding grooves of a window opening section of the window structure, the two moveable casements each being capable of being located entirely in either of a first or a second vertical section in the window opening section; a breast section arranged under the window opening section and having a cavity therein, a horizontal branching section having a groove arranged parallel to the first vertical section and communicating with one of the vertical guiding grooves at a branching point; arched crossing grooves located in a lower portion of the window opening section; direction changing turn-outs arranged at crossing points of the arched crossing grooves and at the branching point of the horizontal branching section, wherein inner walls of the cavity include casement guiding grooves which may receive the two moveable casements, wherein the first vertical section extends along an entire interior vertical extent of both of the window opening section and the breast section, and wherein the second vertical section extends along an entire exterior vertical extent of only the window opening section along an exterior side of the window structure; and a horizontal connecting section connecting the first and second vertical sections.