Flow restrictor

Claim 2

A flow restrictor comprising: a housing defining an enclosed chamber therein; a partition wall, dividing said chamber into first and second separate pressure chambers each of which has a port connected thereto, and having at least one aperture for providing fluidic communication between said first and second chambers; an annular, flexible, umbrella-shaped valve an inner portion of which is secured to said partition wall, said valve closing said at least one aperture for interrupting said fluidic communication between said first and second chambers when the vacuum in said first chamber is greater than that in said second chamber, and opening said aperture for establishing fluidic communication between said first and second chambers when the vacuum in said second chamber is greater than that in said first chamber; an orifice member having an orifice and secured to said partition wall for permitting restricted fluidic communication between said first and second chambers; and filter means positioned between said partition wall and each of said ports, the outer periphery portion of each filter being respectively securely sandwiched between said housing and said partition wall; said partition wall, said valve, and said orifice member being coaxially arranged and wherein said partition wall is provided with a cylindrical projection axially projecting from one side of said partition wall and said orifice member is pressedly inserted into said projection.

Claim 3

A flow restrictor as claimed in claim 1, wherein: said orifice member comprises a cylindrical member, one end of which is closed and is provided with said orifice.

Claim 4

A flow restrictor as claimed in claim 1, wherein: said partition wall is provided with a coaxial cylindrical projection extending from one side thereof, the inner periphery of said valve tightly surrounding the outer periphery of said cylindrical projection.

Claim 5

A flow restrictor as claimed in claim 1, wherein: said cylindrical projection is provided with an annular groove for securely receiving the inner peripheral portion of said valve.

Claim 6

A flow restrictor comprising: a housing defining an enclosed chamber therein; a partition wall, dividing said chamber into first and second separate pressure chambers each of which has a port connected thereto, and having at least one aperture for providing fluidic communication between said first and second chambers; an annular, flexible, umbrella-shaped valve an inner portion of which is secured to said partition wall, said valve closing said at least one aperture for interrupting said fluidic communication between said first and second chambers when the vacuum in said first chamber is greater than that in said second chamber, and opening said aperture for establishing fluidic communication between said first and second chambers when the vacuum in said second chamber is greater than that in said first chamber; an orifice member having an orifice and secured to said partition wall for permitting restricted fluidic communication between said first and second chambers; and filter means positioned between said partition wall and each of said ports, the outer periphery portion of each filter being respectively securely sandwiched between said housing and said partition wall; said partition wall, said valve, and said orifice member being coaxially arranged wherein said partition wall is provided with first and second coaxial cylindrical projections extending oppositely from both sides thereof, the inner periphery of said valve tightly surrounding the outer periphery of said second cylindrical projection; and said orifice member being pressedly inserted into said first cylindrical projection.

Claim 7

A flow restrictor comprising: a housing defining an enclosed chamber therein; a partition wall, dividing said chamber into first and second separate pressure chambers each of which has a port connected thereto, and having at least one aperture for providing fluidic communication between said first and second chambers; an annular, flexible, umbrella-shaped valve an inner portion of which is secured to said partition wall, said valve closing said at least one aperture for interrupting said fluidic communication between said first and second chambers when the vacuum in said first chamber is greater than that in said second chamber, and opening said aperture for establishing fluidic communication between said first and second chambers when the vacuum in said second chamber is greater than that in said first chamber; an orifice member having an orifice and secured to said partition wall for permitting restricted fluidic communication between said first and second chambers; and filter means positioned between said partition wall and each of said ports, the outer periphery portion of each filter being respectively securely sandwiched between said housing and said partition wall; said partition wall, said valve, and said orifice member being coaxially arranged wherein said partition wall is provided with first and second coaxial cylindrical projections extending oppositely from both sides thereof, the inner periphery of said valve tightly surrounding the outer periphery of said second cylindrical projection; and said orifice member being pressedly inserted into said first cylindrical projection.

Claim 8

A flow restrictor as claimed in claim 5, wherein: said port connected to said first chamber is fluidically connected to a port of a carburetor; and said port connected to said second chamber is fluidically connected to a servo motor in a spark advance mechanism of a distributor for a motor vehicle.

Claim 9

A flow restrictor comprising: a housing defining an enclosed chamber therein; a partition wall, dividing said chamber into first and second separate pressure chambers each of which has a port connected thereto, and having at least one aperture for providing fluidic communication between said first and second chambers; an annular, flexible, umbrella-shaped valve an inner portion of which is secured to said partition wall, said valve closing said at least one aperture for interrupting said fluidic communication between said first and second chambers when the vacuum in said first chamber is greater than that in said second chamber, and opening said aperture for establishing fluidic communication between said first and second chambers when the vacuum in said second chamber is greater than that in said first chamber; an orifice member having an orifice and secured to said partition wall for permitting restricted fluidic communication between said first and second chambers; and filter means positioned between said partition wall and each of said ports, the outer periphery portion of each filter being respectively securely sandwiched between said housing and said partition wall; said partition wall, said valve, and said orifice member being coaxially arranged wherein said partition is provided with an axially extending stepped bore; said orifice member comprises a cylindrical portion, having said orifice, and an annular flange portion extending radially outwardly from one end of said cylindrical portion, said cylindrical portion being pressedly inserted into a large diameter portion of said stepped bore and through said valve, and said flange portion presses the inner peripheral portion of said valve onto said partition wall.

Claim 10

A flow restrictor comprising: a housing defining an enclosed chamber therein; a partition wall, dividing said chamber into first and second separate pressure chambers each of which has a port connected thereto, and having at least one aperture for providing fluidic communication between said first and second chambers; an annular, flexible, umbrella-shaped valve an inner portion of which is secured to said partition wall, said valve closing said at least one aperture for interrupting said fluidic communication between said first and second chambers when the vacuum in said first chamber is greater than that in said second chamber, and opening said aperture for establishing fluidic communication between said first and second chambers when the vacuum in said second chamber is greater than that in said first chamber; an orifice member having an orifice and secured to said partition wall for permitting restricted fluidic communication between said first and second chambers; and filter means positioned between said partition wall and each of said ports, the outer periphery portion of each filter being respectively securely sandwiched between said housing and said partition wall; said partition wall, said valve, and said orifice member being coaxially arranged wherein said partition is provided with an axially extending stepped bore; said orifice member comprises a cylindrical portion, having said orifice, and an annular flange portion extending radially outwardly from one end of said cylindrical portion, said cylindrical portion being pressedly inserted into a large diameter portion of said stepped bore and through said valve, and said flange portion presses the inner peripheral portion of said valve onto said partition wall.

Claim 11

A flow restrictor as claimed in claim 7, wherein: said valve is provided with an annular groove at said inner peripheral portion for receiving said flange portion of said orifice member.

Claim 12

A flow restrictor as claimed in claim 7, wherein: said port connected to said first chamber is fluidically connected to a port of an intake manifold; and said port connected to said second chamber is fluidically connected to a port of a change-over valve which controls an atmospheric air supply from an air pump to an exhaust port of an engine for a motor vehicle.