Granted Patent B1

US 7,373,930 · App. 11/843,992 · Granted May 20, 2008

Abstract

Claims (11)

1. A multi-port check-valve for a fuel vapor emissions system coupled to an intake manifold of an internal combustion engine with forced induction and of the type including a purge canister and a purge valve, comprising:

(a) a first port coupled to the purge valve;

(b) a second port in fluid communication with the first port and having a first check-valve with a fixed orifice arranged to open in response to engine vacuum, and, during a boost mode, bleed intake manifold boost pressure; and

(c) a third port in fluid communication with the first and second ports and having a second check-valve arranged to release said boost pressure to atmosphere.

2. The apparatus of claim 1 wherein the second check-valve bleeds the intake manifold boost pressure to an engine's air box.

3. The apparatus of claim 1 wherein said internal combustion engine is turbocharged.

4. In a purge harness of a fuel vapor emissions system of an internal combustion engine with forced induction and of the type including a purge canister and a purge valve, a method for preventing intake manifold boost pressure from reaching the purge valve, comprising:

providing a first check-valve having a fixed orifice, wherein the first check-valve opens in response to engine vacuum drawn by the intake manifold, and the fixed orifice, during a boost mode, bleeds boost pressure received from the intake manifold; and

providing a second check-valve in fluid communication with said first check-valve to release said boost pressure to atmosphere.

5. The method of claim 4 wherein the second check-valve bleeds the intake manifold boost pressure to an engine's air box.

6. The method of claim 4 wherein said engine is turbocharged.

Assignments (18)