Abstract: The present invention concerns an air exhausting device, intended primarily for catering industry kitchens or equivalent. The air exhausting device comprises an outer housing, an exhaust chamber with at least one air aperture or grease filter unit, a collecting chamber for gaseous impurities and a blow chamber. The blow apertures of the blow chamber of the air exhausting device are disposed to produce a blow jet which induces a secondary air jet, which has on all sides of the blow apertures been arranged to act on its entirety in the proximity effect area. Above the blow apertures of the blow chamber has been disposed a guide baffle, arranged to direct the blow jet towards the grease filters to that the maximally efficient starting impulse of the blow jet is achieved, this impulse being arranged to substantially die out before arriving at the grease filter.

Abstract: The control/fire damper (10) comprises a tubular shell (11) constituting a flow duct (12), a shaft (13) disposed within the flow duct (12) and carried by the shell (11), and a closing plate (14) mounted on the shaft (13), and which in the case of fire damper use continuously tends to close under the action of a spring (17). The control/fire damper (10) is provided with a clamping counterpart (15) attached to the closing plate (14) and with a clamping device (16) passing through the shell (11), which fixes the counterpart (15) steplessly in the position which is desired in each instance. The clamping device (16) consists of a clamping screw and, in fire damper use, of a member attached by fuse material to the end of the clamping screw.

Abstract: For controlling and measuring the flow of a gas in a duct, apparatus including a collar member adapted to be sealingly connected to the duct and a plurality of overlapping throttling blades pivotally carried by mounting means situated within the collar member. These blades define the side surface of a truncated cone and have upstream end regions defining the base of the cone and downstream end regions defining the of the truncated cone as well as a throttling aperture through which the gas is adapted to flow. The blades are appropriately shaped and positioned so that one side edge region of each throttling blade overlaps and resiliently engages an adjacent side edge region of an adjacent throttling blade with a positive bearing force which results in a fluidly sealed engagement between each pair of adjacent blades so that the truncated cone defined thereby is rendered gas sealed.