This invention relates to heating components of a combustion engine ventilation system, and more particularly, the invention relates to a heating element for use with a positive crankcase ventilation valve and a heating element for use with a hose from the PCV valve to the intake manifold.
PCV valve assemblies are used to vent unburned combustion gases, which blow by the piston rings and into the engine crankcase into the intake manifold to be burned. Relief of pressure within the crankcase and burning the unburned combustion gases are critical in obtaining desirable engine operation and emissions. Numerous PCV valve actuation devices for opening and closing the valve have been proposed, some of which do not provide valve control to the degree desired. In particular, PCV valve operation may be negatively affected by the temperature. Under some cold conditions, the operation of the PCV valve may be inhibited and the valve may be unusable. That is, the gases in the vicinity PCV valve may freeze thereby preventing the valve from moving. PCV valve assembly heating devices have been used to heat the assembly to better ensure desirable operation. However, they have employed external thermostats to control the flow of current to the heating device to turn the heating device on at the desired temperature. The thermostats add cost to the PCV valve and take up space in the engine compartment. Therefore, what is needed is an improved heating device for a PCV valve assembly.
The PCV valve is typically mounted on a rocker arm cover and connected to the intake manifold by a hose. The hose connection at the intake manifold may be located upstream of the throttle body blade. Cold moist air hitting the throttle body blade may produce ice around the throttle body causing the throttle blade to stick. It is desirable to heat the air entering the intake manifold near the throttle body blade to a temperature sufficiently high to prevent icing of the blade. Therefore, what is needed is a heating device for use with the combustion engine ventilation system to prevent icing of the blade.
The present invention provides a PCV valve assembly including housing having a fluid inlet and outlet. A poppet valve is disposed in the housing between the fluid inlet and outlet and is moveable in an axial direction between a plurality of positions. A heating element having a positive temperature coefficient material is supported in the housing in proximity to at least a portion of the valve for automatically heating the valve in response to a given voltage. The material produces a first heat in response to a first temperature and a the given voltage. The material produces a second heat less than the first heat produced in response to the given voltage and a second temperature greater than the first temperature. That is, the positive temperature coefficient material automatically regulates the flow of current and the temperature produced without the need of a thermostat in response to the same voltage.
The combustion engine ventilation system may also include a positive crankcase ventilation valve housing having a fluid inlet and outlet with a valve assembly arranged in the housing and moveable between a plurality of positions. A hose defining an air passageway and having a length is connected between the fluid outlet and an intake manifold respectively at first and second connections. The hose has a heating element arranged substantially along the length for applying heat to the air passageway. An electrical device is connected to the heating element for providing power to the heating element to generate heat. In this manner, air entering the intake manifold in proximity to the throttle blade is heated to maintain a higher temperature to prevent blade icing.
Accordingly, the above invention provides an improved combustion engine ventilation system including an improved PCV valve.
Other advantages of the present invention can be understood by reference to the following detailed description when considered in connection with the accompanying drawings wherein:
A PCV valve assembly 10 is shown in
The valve 24 may become stuck within the housing in an undesired position during cold conditions. To this end, the assembly 10 includes a heating element 26 that automatically varies the amount of heat generated in response to the surrounding temperature. In this manner, the appropriate amount of heating may be applied to the PCV valve without an additional circuit for turning the valve on and off. A connector 28 extends from a portion of the housing 12 to receive power from a control device 32 that provides the needed current to the heating element 26. The connector 28 has electrical contacts 30 that supplies the current to the heating element 26.
The heating element 26 may include a tubular member 34, preferably constructed from aluminum, that at least partially surrounds the poppet valve 24 for heating the area around the poppet valve to prevent the valve 24 from sticking to the housing 12. A foil 36 constructed from a positive temperature coefficient material is attached to the tubular member 34 and generates heat in response to current applied to the electrical contacts 30. The positive temperature coefficient or PTC material is known in the art and is constructed from a semiconductor material that exhibits characteristics similar to a thermister. The material is sandwiched between two layers of film similar to a strain gauge and is adhered to the surface of the tubular member 34. As shown in
For a given voltage applied to the foil 36, a current is produced in the foil that generates heat. However, the current flowing to the foil 36, and thus the heat generated by the foil, varies based upon the temperature surrounding the foil 36. The lower the temperature on the heating element 26, the more current that goes through the foil 36, thereby providing heat to the PCV valve 10. As the temperature rises about the foil 36, less current passes through the foil 36, thereby providing less heat to the PCV valve in response to the same voltage. In this manner, the heating element 26 is self-regulating and provides a desired amount of heat to the valve assembly 10 through a range of temperature conditions in response to the same voltage. Of course, the voltage to the heating element 26 may be varied.
Another embodiment of the heating element 26 is shown in
The housing portion 40 and valve cover 38 may respectively include seals 50 and 51 that seal about the secondary housing 42. The heating element 26 may be arranged about the secondary housing 42 to heat the poppet valve located within. A hose 52 is secured to an end of the housing portion 40 to carry gases from the valve cover 38 to the intake manifold, as is known in the art.
A combustion engine ventilation system is shown schematically at 54 in
As been shown in
Referring to
Referring to
An additional connector configuration is shown at
The invention has been described in an illustrative manner, and it is to be understood that the terminology that has been used is intended to be in the nature of words of description rather than of limitation. Obviously, many modifications and variations of the present invention are possible in light of the above teachings. It is, therefore, to be understood that within the scope of the appended claims the invention may be practiced otherwise than as specifically described.
This application is the National Stage of PCT Application Number PCT/US02/27697 filed on Aug. 29, 2002, which claims priority to U.S. Provisional Patent No. 60/316,009 filed on Aug. 30, 2001.
Filing Document | Filing Date | Country | Kind | 371c Date |
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PCT/US02/27697 | 8/29/2002 | WO | 00 | 6/22/2004 |
Publishing Document | Publishing Date | Country | Kind |
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WO03/021087 | 3/13/2003 | WO | A |
Number | Name | Date | Kind |
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5758826 | Nines | Jun 1998 | A |
5970962 | Nelson et al. | Oct 1999 | A |
6044829 | Butz et al. | Apr 2000 | A |
6102303 | Bright et al. | Aug 2000 | A |
6478043 | Ishigaki | Nov 2002 | B2 |
6546921 | Callahan | Apr 2003 | B1 |
Number | Date | Country | |
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20040231651 A1 | Nov 2004 | US |
Number | Date | Country | |
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60316009 | Aug 2001 | US |