Internal-combustion engines – Charge forming device – Exhaust gas used with the combustible mixture
Reexamination Certificate
1998-11-25
2001-01-09
Wolfe, Willis R. (Department: 3747)
Internal-combustion engines
Charge forming device
Exhaust gas used with the combustible mixture
Reexamination Certificate
active
06170476
ABSTRACT:
FIELD OF THE INVENTION
This invention relates generally to automotive emission control valves, such as exhaust gas recirculation (EGR) valves that are used in exhaust emission control systems of automotive vehicle internal combustion engines. More specifically, the invention relates to the integration of a sensor, a fluid pressure regulator valve, and a fluid-pressure-operated actuator in an EGR valve to create an EGR module, hereinafter sometimes referred to as a “Modular EGR”.
BACKGROUND OF THE INVENTION
U.S. Pat. Nos. 5,241,940 (Gates, Jr.) and 5,613,479 (Gates et al.), which are hereby incorporated by reference, disclose EGR systems of the type in which a module that embodies principles of the present invention is useful.
SUMMARY OF THE INVENTION
The inventive module possesses a novel construction that provides important economic and functional advantages relating to fabrication, assembly, testing, installation, and use.
One generic aspect of the invention relates to an automotive emission control module comprising: an emission control valve body having an internal main flow passage between a first port and a second port, a valve for selectively restricting flow between the ports, an actuator for operating the valve, a pressure sensor having first and second pressure sensing ports, and first and second pressure sensing passages communicating the first and second pressure sensing ports to the main flow passage for sensing pressure differential along a portion of the length of the flow passage, the second pressure sensing passage extending through the actuator and comprising a chamber space that is disposed between the actuator and the pressure sensor.
Within this one generic aspect, some of the more specific aspects relate to the actuator comprising a shaft for operating the valve and an actuator body that contains two chamber spaces separated by a movable actuator wall that operates the shaft; the actuator body mounting on the emission control valve body, and the chamber space being arranged in axial succession along an axis of the module beyond the actuator relative to the valve; a separator wall separating the chamber space from the actuator, wherein the separator wall comprises an annulus having an inner margin sealed to an outside diameter of the shaft and an outer margin sealed to the actuator body; the inner margin of the separator wall annulus moving with the shaft; the actuator comprising a movable actuator wall dividing the actuator into two variable volume chamber spaces, and a spring being disposed within one of the two actuator chamber spaces to urge the valve toward closing the main flow passage; the actuator comprising an actuator body that mounts on the emission control valve body, and the second pressure sensing passage being internal to both the emission control valve body and the actuator body; including an orifice disposed in the main flow path between the first port and the valve for creating pressure differential between the first and second pressure sensing passages, and in which the first pressure sensing passage comprises a hole that extends through a wall of the emission control valve body circumscribing a location in the main flow passage that is between the first port and the orifice, and further including a tube extending from the hole external to the emission control valve body.
Still more of these more specific aspects relate to: the inclusion of a pressure regulating valve that comprises a source pressure port and a regulated pressure port and that, in accordance with a regulation signal, modulates source pressure at the source pressure port to a regulated pressure at the regulated pressure port, and in which the first pressure sensing passage communicates the first port to the source pressure port of the pressure regulating valve, and the regulated pressure port of the pressure regulating valve communicates with the actuator; the actuator comprising a shaft for operating the valve and two chamber spaces separated by a movable actuator wall that operates the shaft, the regulated pressure port of the pressure regulating valve communicating with one of the two chamber spaces of the actuator, and the other chamber space of the actuator communicating with atmosphere; the second pressure sensing passage comprising a chamber space arranged in axial succession with the actuator chamber spaces along an axis of the module, and the chamber space of the second pressure sensing passage being disposed axially beyond the two actuator chamber spaces relative to the valve; a separator wall dividing the chamber space of the second pressure sensing passage from the one chamber space of the actuator and comprising an annulus having an inner margin sealed to an outside diameter of the shaft and an outer margin sealed to a body of the actuator; the inclusion of an orifice disposed in the main flow path between the first port and the valve for creating pressure differential between the first and second pressure sensing passages, and in which the shaft comprises a tube, the valve comprises a stem extending from a head, one end of the tube is telescopically engaged with a free end of the stem, and the chamber space communicates via the tube and the stem with a location in the main flow passage that is between the first port and the orifice; and the chamber space communicating with the location in the main flow passage that is between the first port and the orifice via an opening in a side wall of the tube that is unoccluded by the telescopic engagement of the one tube end with the free end of the stem.
A further generic aspect relates to an automotive emission control module comprising: an emission control valve body having an internal main flow passage, a valve for selectively restricting the flow passage, an actuator comprising an actuator mechanism for operating the valve, a pressure sensor that provides a signal related to pressure communicated to the pressure sensor, and a pressure sensing passage communicating pressure to the pressure sensor from a location in the main flow passage, the pressure sensing passage including a variable volume chamber space which is external to the actuator mechanism, and the volume of which varies with the operation of the valve by the actuator mechanism.
Within this further generic aspect, more specific aspects relate to: the actuator mechanism comprising two chamber spaces separated by a movable actuator wall that operates the valve, and all three chamber spaces being disposed in axial succession along an axis of the module; the variable volume chamber space being disposed axially beyond the two chamber spaces of the actuator mechanism relative to the valve; the actuator mechanism comprising a movable actuator wall that divides the two chamber spaces of the actuator mechanism and that operates the valve via a tube which forms a portion of the pressure sensing passage; a spring being disposed within one of the chamber spaces of the actuator mechanism and acting on the movable actuator wall to urge the valve head toward seating on a valve seat; and a movable separator wall divides the variable volume chamber space from one of the two chamber spaces of the actuator mechanism and comprises an annulus having an inner margin sealed to an outside diameter of the tube and an outer margin sealed to a body of the actuator that contains the actuator mechanism.
Still another generic aspect relates to an automotive emission control module comprising: an emission control valve body having an internal main flow passage between a first port and a second port, a valve for selectively restricting the flow passage, an actuator, comprising an actuator body mounted on the emission control valve body, for operating the valve, an electric pressure sensor mounted on the actuator body and having a pressure sensing port ported to the main flow passage, an electric-operated fluid pressure regulator valve mounted on the actuator body for providing regulated fluid pressure to operate the actuator, one of the pressure sensor and the actuator body comprising
Busato Murray F.
Cook John E.
Siemens Canada Ltd.
Wolfe Willis R.
LandOfFree
Internal sensing passage in an exhaust gas recirculation module does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Internal sensing passage in an exhaust gas recirculation module, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Internal sensing passage in an exhaust gas recirculation module will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2466914