Charge forming device with air bleed control valve

Patent metadata

Field	Value
Publication number	US-10415508-B2
Application number	US-201615763358-A
Country	US
Kind code	B2
Filing date	Oct 7, 2016
Priority date	Oct 9, 2015
Publication date	Sep 17, 2019
Grant date	Sep 17, 2019

Abstract

In at least some implementations, a charge forming device includes a body defining at least part of a first passage, a throttle valve movable relative to the first passage between an idle position and a wide open position, an air bleed passage communicated with the first passage, and a control valve. The control valve may be arranged in the air bleed passage to selectively inhibit or prevent air flow to the first passage from the air bleed passage. And the control valve is moveable between a first position and a second position in response to movement of the throttle valve wherein greater air flow is permitted from the air bleed passage to the first passage in the body when the control valve is in the second position than when the control valve is in the first position.

First claim

The invention claimed is:

1. A charge forming device, comprising:
a body defining at least part of a first passage through which fuel or air or both flows for delivery to an engine;
a throttle valve movable relative to the first passage between an idle position and a wide open position;
an air bleed passage communicated with the first passage to provide a supply of air to the first passage; and
a control valve arranged in the air bleed passage to selectively inhibit or prevent air flow to the first passage from the air bleed passage, the control valve being moveable between a first position and a second position in response to movement of the throttle valve wherein greater air flow is permitted from the air bleed passage to the first passage in the body when the control valve is in the second position than when the control valve is in the first position, and wherein the throttle valve includes or cooperates with a driving surface that, during at least a portion of the movement of the throttle valve between the idle position and the wide open position, causes displacement of the control valve.

2. The device of claim 1 wherein the control valve is driven by the throttle valve between its first and second positions.

3. The device of claim 1 wherein a lost motion coupling is provided between the throttle valve and the control valve, and wherein the control valve is in the first position when the throttle valve is in the idle position and until the throttle valve is moved a threshold amount toward the wide open position.

4. The device of claim 3 wherein the threshold amount is between 30% and 90%.

5. The device of claim 1 wherein the first passage is a fuel and air mixing passage through which a fuel and air mixture is discharged for delivery to an engine, the body defines at least part of a fuel circuit through which fuel is delivered to the first passage and the air bleed passage communicates with the fuel circuit upstream of the first passage to provide air from the air bleed passage into the fuel circuit at least when the control valve is in the second position.

6. The device of claim 1 wherein the body defines a throttle valve bore, the throttle valve is generally cylindrical and received within the throttle valve bore for rotation relative to the body about an axis and the first passage intersects the throttle valve bore, and wherein at least portions of the drive surface are arranged at a varying distance from the axis and the drive surface engages and displaces the control valve during at least a portion of the rotation of the throttle valve.

7. The device of claim 6 which also includes a valve seat engaged by the control valve when the control valve is in the first position, and wherein the control valve includes a projection that extends through the valve seat and is engaged by the drive surface during at least a portion of the rotation of the throttle valve.

8. The device of claim 1 wherein the control valve includes a follower that is engaged by the driving surface.

9. The device of claim 1 wherein the throttle valve includes a cam portion that includes the drive surface.

10. The device of claim 1 wherein the throttle valve rotates about an axis and the drive surface is not circular relative to the axis.

11. The device of claim 1 wherein the throttle valve includes a throttle valve shaft the drive surface is defined by an outer surface of the throttle valve shaft.

12. A charge forming device, comprising:
a body defining at least part of a first passage through which fuel or air or both flows for delivery to an engine;
a throttle valve movable relative to the first passage between an idle position and a wide open position;
an air bleed passage communicated with the first passage to provide a supply of air to the first passage; and
a control valve arranged in the air bleed passage to selectively inhibit or prevent air flow to the first passage from the air bleed passage, the control valve being moveable between a first position and a second position in response to movement of the throttle valve wherein greater air flow is permitted from the air bleed passage to the first passage in the body when the control valve is in the second position than when the control valve is in the first position, wherein the control valve is driven by the throttle valve between its first and second positions, and which also includes a valve seat against which the control valve is engaged in the first position, and wherein the throttle valve includes a cam portion that has a distance from the valve seat that varies as the throttle valve is moved between the idle position and wide open position.

13. A charge forming device, comprising:
a body defining at least part of a first passage through which fuel or air or both flows for delivery to an engine;
a throttle valve movable relative to the first passage between an idle position and a wide open position;
an air bleed passage communicated with the first passage to provide a supply of air to the first passage; and
a control valve arranged in the air bleed passage to selectively inhibit or prevent air flow to the first passage from the air bleed passage, the control valve being moveable between a first position and a second position in response to movement of the throttle valve wherein greater air flow is permitted from the air bleed passage to the first passage in the body when the control valve is in the second position than when the control valve is in the first position, wherein the throttle valve is rotatable about an axis between the idle position and wide open position, and wherein the throttle valve includes a drive surface that is not circular relative to the axis and the drive surface causes movement of the control valve between the first and second positions as the throttle valve is rotated.

14. The device of claim 13 wherein a lost motion coupling is provided between the throttle valve and the control valve so that some rotation of the throttle valve occurs without a corresponding movement of the control valve.

15. The device of claim 13 wherein the first passage is a fuel and air mixing passage through which a fuel and air mixture is discharged for delivery to an engine, the body includes a valve shaft bore that intersects the fuel and air mixing passage and the throttle valve includes a throttle valve shaft received for rotation about the axis within the valve shaft bore and a throttle valve head carried by the throttle valve shaft and wherein the drive surface is carried by or formed on the throttle valve shaft.

16. The device of claim 15 wherein part of the air bleed passage intersects the valve shaft bore and the control valve is received within said part of the air bleed passage.

17. The device of claim 16 wherein the control valve includes a follower and a valve body that are received in said part of the air bleed passage that intersects the valve shaft bore, the follower being engaged by and moved within the air bleed passage by the drive surface during a portion of the rotation of the throttle valve shaft and the follower engaging the valve body during at least a portion of the movement of the follower to move the valve body between open and closed positions.

18. The device of claim 13 which also includes a valve seat defining an opening and wherein the control valve engages the valve seat when the control valve is in the first position, and wherein the control valve includes a portion that extends through the opening and said portion of the control valve that extends through the opening is engage

Assignees

• Walbro Llc

Inventors

• Schmidt Thomas L

Classifications

• F02M17/04

  having fuel inlet valve controlled by diaphragm · CPC title

• F02M7/26 Primary

  dependent on position of optionally operable throttle means · CPC title

• F02M9/08

  having throttling valves rotatably mounted in the passage · CPC title