Engine induction air flow control

An internal combustion engine air cleaner comprising a snorkel having upper and lower members defining a generally horizontal induction air flow conduit including an end open to air at ambient temperature, said members having lateral projections defining a pair of channels disposed outwardly and on opposite sides of said conduit downstream of said end and opening into said conduit, said lower member further having a lower recess, an intermediate member overlying said recess to define an auxiliary air inlet chamber below said conduit and separated therefrom by said intermediate member, said chamber being adapted for connection to a source of heated air, said intermediate member including a pair of depending flanges separating said chamber from said channels, said flanges having openings permitting generally horizontal air flow from said chamber to said channels, a pivot pin supported by said intermediate member at the bottom of said conduit between said end and said channels, a guide member pivoted on said pin and extending upwardly and downstream therefrom, a coiled bimetal disposed in said conduit downstream of said channels, a control arm connecting said bimetal to said guide member to bias said guide member upwardly about said pivot at induction air flow temperatures below a selected value and permitting lowering of said guide member about said pivot pin at induction air flow temperatures below the selected value and positioning said guide member intermediate its uppermost and lowermost positions to maintain the selected induction air flow temperature, a damper member pivoted on said pin and extending upwardly and downstream therefrom and underlying said guide member, said damper member having a main blade portion disposed in said conduit for controlling flow through said end and a pair of lateral blade portions disposed in said channels for controlling heated air flow through said openings, and spring means biasing said damper member and said guide member for concomitant operation whereby said bimetal positions said damper member to obstruct ambient air flow and to permit heated air flow at induction air flow temperatures below the selected value, to permit ambient air flow and to obstruct heated air flow at induction air flow temperatures above the selected value, and to proportion ambient air flow and heated air flow to maintain the selected induction air flow temperature, and further whereby said damper member may move downwardly about said pivot pin against the bias of said spring means to permit ambient air flow and to obstruct heated air flow at induction air flow rates above a selected value.

An internal combustion engine air cleaner comprising a snorkel having upper and lower members defining a generally horizontal induction air flow conduit including an end open to air at ambient temperature, said members having lateral projections defining a pair of channels disposed outwardly and on opposite sides of said conduit downstream of said end and opening into said conduit, said lower member further having a lower recess, an intermediate member overlying said recess to define an auxiliary air inlet chamber below said conduit and separated therefrom by said intermediate member, said chamber being adapted for connection to a source of heated air, said intermediate member including a pair of depending flanges separating said chamber from said channels, said flanges having openings permitting generally horizontal air flow from said chamber to said channels, a pivot pin supported by said intermediate member at the bottom of said conduit between said end and said channels, a damper member pivoted on said pin and having a main blade portion extending upwardly and downstream therefrom in said conduit for controlling flow through said end and a pair of lateral blade portions disposed in said channels and adapted to traverse said flange openings for controlling heated air flow therethrough independent of the rate of air flow therethrough, and means for positioning said damper member to obstruct ambient air flow and to permit heated air flow at induction air flow temperatures below a selected value, to permit ambient air flow and to obstruct heated air flow at induction air flow temperatures above the selected value, to proportion ambient air flow and heated air flow to maintain the selected induction air flow temperature, and further to permit ambient air flow and to obstruct heated air flow irrespective of induction air flow temperature at induction air flow rates above a selected value.