Multiple tap aspirator

Patent metadata

Field	Value
Publication number	US-2015114348-A1
Application number	US-201314062323-A
Country	US
Kind code	A1
Filing date	Oct 24, 2013
Priority date	Oct 24, 2013
Publication date	Apr 30, 2015
Grant date	—

Abstract

Systems and methods are provided for engine systems including a vacuum-powered multiple tap aspirator coupled between atmospheric, an engine crankcase, or another source and a vacuum source such as a compressor inlet or engine intake manifold. The multiple tap aspirator includes a suction tap arranged in a throat of the aspirator, a suction tap arranged in a diverging cone of the aspirator, and a suction tap arranged in a straight exit tube downstream of the diverging cone of the aspirator. The aspirator provides vacuum generation and suction flow over a range of vacuum levels at the suction taps, and suction flow only passes through a single check valve before entering the aspirator.

First claim

1 . An engine system, comprising:
an aspirator with a suction tap in a throat of the aspirator, a suction tap in a diverging cone of the aspirator, and a suction tap in a straight tube downstream of the diverging cone, a motive inlet of the aspirator coupled with atmosphere and a mixed flow outlet of the aspirator coupled with a vacuum source.

2 . The engine system of claim 1 , wherein the suction taps are coupled with a vacuum reservoir via respective parallel suction passages, wherein the passages merge into a single passage downstream of the vacuum source, and wherein a check valve is arranged in each passage.

3 . The engine system of claim 2 , wherein the mixed flow outlet of the aspirator is coupled with an intake manifold of the engine.

4 . The engine system of claim 2 , wherein the mixed flow outlet of the aspirator is coupled with an intake passage of the engine upstream of a boost device and downstream of an air induction system throttle.

5 . The engine system of claim 2 , wherein suction flow from the vacuum reservoir into each tap of the aspirator passes through only one check valve before entering the tap.

6 . The engine system of claim 1 , wherein the suction tap in the throat and the suction tap in the straight tube are coupled with a vacuum reservoir via respective parallel suction passages merging into a single passage downstream of the vacuum source, wherein the suction tap in the diverging cone is coupled with a fuel vapor canister, and wherein a check valve is arranged in each passage.

7 . The engine system of claim 6 , wherein the mixed flow outlet of the aspirator is coupled with an intake manifold of the engine.

8 . The engine system of claim 7 , wherein suction flow into each tap of the aspirator passes through only one check valve before entering the tap.

9 . A method for an engine, comprising:
directing atmospheric air through an aspirator comprising a suction tap in a throat of the aspirator, a suction tap in a diverging cone of the aspirator, and a suction tap in a straight tube downstream of the diverging cone into an intake manifold of the engine based on pressure at a mixed flow outlet of the aspirator.

10 . The method of claim 9 , wherein the directing is further based on pressure in an intake manifold of the engine coupled with the mixed flow outlet of the aspirator.

11 . The method of claim 9 , further comprising compensating engine air-fuel ratio based on the flow entering the intake manifold from the aspirator if the suction tap in the diverging cone of the aspirator is coupled with a fuel vapor canister.

12 . The method of claim 11 , wherein the directing is further based on a pressure in the fuel vapor canister.

13 . The method of claim 9 , wherein the directing is further based on a vacuum level in a vacuum reservoir coupled to one or more of the suction taps.

14 . The method of claim 9 , wherein directing atmospheric air through the aspirator comprises increasing opening of an aspirator shut off valve arranged in series with a motive inlet of the aspirator.

15 . The method of claim 14 , further comprising closing the aspirator shut off valve when intake manifold pressure exceeds atmospheric pressure.

16 . The method of claim 11 , wherein compensating engine air-fuel ratio based on the flow entering the intake manifold from the aspirator comprises determining a composition and amount of fluid exiting a mixed flow outlet of the aspirator and adjusting fuel injection based on a desired engine air-fuel ratio and the composition and amount of fluid exiting the mixed flow outlet of the aspirator.

17 . A method for an engine, comprising:
directing crankcase gases through an aspirator comprising a suction tap in a throat of the aspirator, a suction tap in a diverging cone of the aspirator, and a suction tap in a straight tube downstream of the diverging cone into an engine intake system when crankcase pressure exceeds a threshold.

18 . The method of claim 17 , wherein the crankcase gases are directed into an intake manifold of the engine.

19 . The method of claim 18 , wherein directing crankcase gases through the aspirator comprises increasing opening of an aspirator shut off valve arranged in series with a motive inlet of the aspirator, the method further comprising closing the aspirator shut off valve when intake manifold pressure exceeds crankcase pressure.

20 . The method of claim 17 , wherein the crankcase gases are directed into an intake passage of the engine upstream of boost device and downstream of an air induction system throttle, the method further comprising adjusting the air induction system throttle based on a desired level of flow through the aspirator.

Assignees

• Ford Global Tech Llc

Inventors

• Pursifull Ross Dykstra
• Vanderwege Brad Alan

Classifications

• F04F5/14

  the inducing fluid being elastic fluid · CPC title

• F04F5/52

  of evacuating pumps · CPC title

• F02M35/10229 Primary

  the intake system acting as a vacuum or overpressure source for auxiliary devices, e.g. brake systems; Vacuum chambers (air storage chamber F02B21/00) · CPC title

• F02M35/1272

  using absorbing, damping, insulating or reflecting materials, e.g. porous foams, fibres, rubbers, fabrics, coatings or membranes · CPC title

• F02M35/10

  Air intakes; Induction systems · CPC title