Louvre window

1. A louvre window having:

a frame, the frame having a head, a sill and at least two jambs;

a drive bar located in one or both of the jambs that is movable by a handle;

a plurality of blades located within the frame and connected to the drive bar by a pivot drive connector, such that movement of the drive bar urges the blades to pivot, each blade having:

a first windowpane attached to the blade; and

a second windowpane attached to the blade,

wherein operation of the handle causes movement of the blades between an open position and a closed position, wherein in the closed position the first windowpanes are aligned to form a barrier against airflow and the second windowpanes are aligned to form a barrier against airflow and in the open position the first windowpanes are pivoted out of alignment to allow airflow and the second windowpanes are pivoted out of alignment to allow airflow;

wherein the drive bar includes a pair of link bars and the pivot drive connector is connected to a respective link bar at opposite sides of the pivot drive connector such that differential translation of the link bars causes pivoting of the pivot drive connector; and

wherein the link bars each have an upper and a lower recess for each pivot drive connector at an interior edge thereof, and the pivot drive connector has a boss that conforms to each recess, such that when the link bars are differentially translated, the boss releasably snaps into the upper recess of one link bar and the lower recess of the other link bar.

2. The louvre window of claim 1 , wherein the first and second windowpane of each blade are offset in a first direction by a first amount, and

wherein the first and second windowpane of each blade are offset in a second direction by a second amount, and

wherein the first direction is perpendicular to the second direction and the first amount is greater than the second amount.

3. The louvre window of claim 1 , wherein each blade further includes a cap member between the first and second windowpane.

4. The louvre window of claim 3 , wherein each blade further includes a sliding member mounted to be movable in a second direction and to which the first windowpane is attached, the sliding member having an upper end extending over the first windowpane, and wherein the cap member has a lower end extending below second windowpane such that, when the blades move from the closed position to the open position, the lower end of the cap member of an upper blade abuts the upper end of the sliding member of a lower blade to urge the first windowpane of the lower blade in the second direction.

5. The louvre window of claim 4 , wherein the sliding member further includes a lower end extending toward the lower end of the cap member such that, when the upper and lower blades move from the open position to the closed position, the upper end of the sliding member of the lower blade abuts the lower end of the sliding member of the upper blade to maintain separation between the second windowpane of the upper blade and the first windowpane of the lower blade.

6. The louvre window of claim 5 , wherein the cap member has an upper end that extends above the second windowpane such that, when the upper and lower blades move from the open position to the closed position, the upper end of the cap member of the lower blade abuts the lower end of the sliding member of the upper blade to urge the first windowpane of the upper blade opposite the second direction.

7. The louvre window of claim 1 , wherein each blade further includes

a slide drive member that pivots together with the pivot drive connector, the slide drive member having a recess that pivots with the slide drive member, and

a sliding member mounted to be movable in a first direction parallel to the first windowpane and having a lower end that extends in a second direction normal to the first windowpane as well as a drive boss received by the recess in the slide drive member,

wherein, when the blades are driven from the closed position to the open position, the slide drive member pivots and thereby urges the sliding member in the first direction to increase a distance between the first windowpane and the second windowpane.

8. The louvre window of claim 7 , wherein the sliding member is attached to the blade by at least two pivotable arm to allow movement of the sliding member in the second direction, such that the upper and lower blades are pivotable by about 90 degrees between the closed position and the open position.

9. The louvre window of claim 7 , wherein the drive boss of the sliding member includes a roller to reduce friction between the drive boss and the recess of the slide drive member.

10. The louvre window of claim 1 , wherein, in the open position, the second windowpane of an upper blade is aligned with the first windowpane of a lower blade to form a channel with substantially uninterrupted walls to promote airflow.

11. A louvre window having:

a frame, the frame having a head, a sill and at least two jambs;

a drive bar located in one or both of the jambs that is movable by a handle;

a plurality of blades located within the frame and connected to the drive bar by a pivot drive connector, such that movement of the drive bar urges the blades to pivot, each blade having:

a first windowpane attached to the blade; and

a second windowpane attached to the blade,

wherein operation of the handle causes movement of the blades between an open position and a closed position, wherein in the closed position the first windowpanes are aligned to form a barrier against airflow and the second windowpanes are aligned to form a barrier against airflow and in the open position the first windowpanes are pivoted out of alignment to allow airflow and the second windowpanes are pivoted out of alignment to allow airflow,

wherein each blade further includes

a slide drive member that pivots together with the pivot drive connector, the slide drive member having a recess that pivots with the slide drive member, and

a sliding member mounted to be movable in a first direction parallel to the first windowpane and having a lower end that extends in a second direction normal to the first windowpane as well as a drive boss received by the recess in the slide drive member,

wherein, when the blades are driven from the closed position to the open position, the slide drive member pivots and thereby urges the sliding member in the first direction to increase a distance between the first windowpane and the second windowpane.

12. The louvre window of claim 11 , wherein the sliding member is attached to the blade by at least two pivotable arm to allow movement of the sliding member in the second direction, such that the blades are pivotable by about 90 degrees between the closed position and the open position.

13. The louvre window of claim 11 , wherein the drive boss of the sliding member includes a roller to reduce friction between the drive boss and the recess of the slide drive member.

14. The louvre window of claim 11 , wherein the drive bar includes a pair of link bars and the pivot drive connector is connected to a respective link bar at opposite sides of the pivot drive connector such that differential translation of the link bars causes pivoting of the pivot drive connector.

15. The louvre window of claim 11 , wherein, in the open position, the second windowpane of an upper blade is aligned with the first windowpane of a lower blade to form a channel with substantially uninterrupted walls to promote airflow.

16. A louvre window having:

a frame, the frame having a head, a sill and at least two jambs;

a drive bar located in one or both of the jambs that is movable by a handle;

a plurality of blades located within the frame and connected to the drive bar by a pivot drive connector, such that movement of the drive bar urges the blades to pivot, each blade having:

a first windowpane attached to the blade; and

a second windowpane attached to the blade,

wherein operation of the handle causes movement of the blades between an open position and a closed position, wherein in the closed position the first windowpanes are aligned to form a barrier against airflow and the second windowpanes are aligned to form a barrier against airflow and in the open position the first windowpanes are pivoted out of alignment to allow airflow and the second windowpanes are pivoted out of alignment to allow airflow,

wherein each blade further includes a cap member between the first and second windowpane, and

wherein each blade further includes a sliding member mounted to be movable in a second direction and to which the first windowpane is attached, the sliding member having an upper end extending over the first windowpane, and wherein the cap member has a lower end extending below second windowpane such that, when the blades move from the closed position to the open position, the lower end of the cap member of an upper blade abuts the upper end of the sliding member of a lower blade to urge the first windowpane of the lower blade in the second direction.

17. The louvre window of claim 16 , wherein the sliding member further includes a lower end extending toward the lower end of the cap member such that, when the blades move from the open position to the closed position, the upper end of the sliding member of the lower blade abuts the lower end of the sliding member of the upper blade to maintain separation between the second windowpane of the upper blade and the first windowpane of the lower blade.

18. The louvre window of claim 17 , wherein the cap member has an upper end that extends above the second windowpane such that, when the blades move from the open position to the closed position, the upper end of the cap member of the lower blade abuts the lower end of the sliding member of the upper blade to urge the first windowpane of the upper blade opposite the second direction.

19. The louvre window of claim 16 , wherein, in the open position, the second windowpane of an upper blade is aligned with the first windowpane of a lower blade to form a channel with substantially uninterrupted walls to promote airflow.