WO1995012775B1

WO1995012775B1 - Check valve for a discharge air duct

Info

Publication number: WO1995012775B1
Application number: PCT/CA1994/000458
Authority: WO
Filing date: 1994-08-05
Publication date: 1995-06-15

Abstract

Valve (10) comprising a housing (20) with an air inlet (23) mounted at the end of a discharge air duct of a domestic appliance, and with an air outlet (24) communicating with the outside. The valve (10) includes a shoulder (41) sealed to the air inlet (23). A ball (42) is received in the housing (20) and is movable on a guide (43) between first and second positions. When there is no airflow from the duct (60), the ball sealingly engages the shoulder (41) under gravity so as to prevent air from being introduced into the duct from outside through gusts of wind. The shoulder (41) and the ball (42) can be made from an insulating material in order to reduce conductive heat loss in cold weather. When the domestic appliance is operating, the ball (42) moves towards the second position under the discharge airflow in order to evacuate said airflow. As soon as the appliance is stopped, the ball (42) resumes automatically its initial position. The valve (10) may be advantageously mounted on any forced air outlet that can be found on various devices, such as air outlets for driers, for toilet ventilating devices, for air exchangers or kitchen hoods, to replace conventional pivoting valves.

Claims

AMENDED CLAIMS [received by the International Bureau on 16 May 1995 (16.05.95); claims 1-5 replaced by new claims 1-3 (2 pages)]

Domestic air vent valve (60), the valve (10) comprising: a housing (20) having an air inlet (23), an air outlet (24) and a means (25) for connecting the air inlet (23) to one end of the duct

(60); a shoulder (41) located inside the housing and in front of the air inlet (23); a bale (42) movable between a first position where the bale (42) rests substantially hermetically and by gravity against one shoulder (41), and a second position where the bale (42) is moved away from the shoulder (41) and above the level of the first position; a guide (43) in the housing (20) for guiding the bale (42) between the first and second positions; and a seat (51) on which bears the ball (42) in the second position; the valve (10) being characterized in that the bale (42) and the shoulder (41) are made of an insulating material, the bale (42) being moved to the second position under the effect of a flow of stale air and is kept stable at the second position under the effect of a pressure differential created by a passage (30) connecting the top of the seat (51) to the vicinity of the air outlet (24).

2. Valve according to claim 1, characterized in that the passage (30) is constituted by a double wall in the housing (20), the double wall comprising an outer wall (27) and an inner wall (28).

Valve according to claim 1 or 2, characterized in that the air outlet (24) faces downwards and is provided with a protective grid (26).

DECLARATIONSELONL'ARTICLE19

Claim 1 has been modified to take into account documents located during the course of the international search. The part describing the previous achievements and the characterizing part have been reformulated accordingly.

In short, the claims now relate to a valve for domestic stale air duct. as opposed to a valve serving in particular for a liquid fluid and intended in particular for industry.

The characterizing part of claim 1 now states that the bale (42) and the shoulder (41) are made of insulating material, which is not shown in US-A-4,624,176. It has also been specified that the ball

(42) is moved to the second position under the effect of a stale airflow and is kept stable at the second position under the effect of a pressure differential created by a passage (30) connecting the top of the seat (51) in the vicinity of the air outlet (24 ..

The new claim 2 is substantially identical to the old claim 3.

The new claim 3 incorporates what was stated in the former claim 4 and further specifies that the air outlet (24) is downwardly oriented.