Patent Application
20190389277
This disclosure relates to an air extractor for a vehicle and a method of manufacturing the air extractor.
Vehicles can include an air extractor. Flow can move through an opening in the air extractor, as required, to balance a pressure inside the vehicle with a pressure outside the vehicle. The air extractor can be located, for example, behind a bumper at a rear of the vehicle.
The air extractor can include flaps moveable between positions that permit flow through the opening and positions that block flow through the opening. The flaps can block contaminants, such as dust and exhaust gases, from moving through the opening when flow is not moving through the air extractor to balance the pressure.
An air extractor manufacturing method according to an exemplary aspect of the present disclosure includes, among other things, molding a flap in a sealed position against a housing of an air extractor. The housing has a first material composition and the flap has a second, different material composition.
Another example of the foregoing method includes molding the flap such that the flap is hingedly coupled to the housing.
Another example of the foregoing method includes molding a seal about a perimeter of the housing.
In another example of the foregoing method, the housing is molded in a first shot, the seal is then molded in a second shot, and the flap is then molded in a third shot.
In another example of the foregoing method, the seal has a material composition that is different than the first and the second material compositions.
In another example of the foregoing method, the flap is configured to passively move back and forth between the sealed position and a pressure releasing position.
In another example of the foregoing method, the flap in the sealed position permits less flow through an aperture of the housing than the flap in the pressure releasing position.
In another example of the foregoing method, the flap in the sealed position permits nominally no flow through the aperture.
In another example of the foregoing method, the flap in the sealed position directly contacts the housing at a hinged connection and directly contacts an edge of the housing. The hinged connection and the edge of the housing are on opposite sides of an opening within the housing.
In another example of the foregoing method, the flap includes an enlarged area on a first side of the housing and a primary portion of the flap on an opposite, second side of the housing.
An air extractor assembly according to another exemplary aspect of the present disclosure includes, among other things, a housing having a first material composition, and a flap having a different, second material composition. The flap is moveable relative to the housing between a sealed position and a pressure releasing position. The flap is molded in the sealed position and coupled to the housing when molded.
In another example of the foregoing assembly, the flap in the sealed position permits less flow through an aperture of the housing than the flap in the pressure releasing position.
In another example of any of the foregoing assemblies, the flap in the sealed position permits nominally no flow through the aperture.
In another example of any of the foregoing assemblies, the flap is biased toward the sealed position due to the flap being molded in the sealed position.
In another example of any of the foregoing assemblies, the flap is hingedly coupled to the housing.
Another example of any of the foregoing assemblies includes a seal about a perimeter of the housing. The seal has a material composition that is different than both the first and the second material compositions.
In another example of any of the foregoing assemblies, the seal is covalent bonded to the housing.
In another example of any of the foregoing assemblies, the flap in the sealed position includes an enlarged area on a first side of the housing and a primary portion on an opposite, second side of the housing.
In another example of any of the foregoing assemblies, the flap in the sealed position directly contacts the housing at a hinged connection and directly contacts an edge of the housing. The hinged connection and the edge of the housing are on opposite sides of an opening within the housing.
The various features and advantages of the disclosed examples will become apparent to those skilled in the art from the detailed description. The figures that accompany the detailed description can be briefly described as follows:
This disclosure details an exemplary method of manufacturing an air extractor, and an air extractor manufactured by that method. Flaps of the air extractor are molded against a housing of the air extractor when the flaps are in a sealed position. Such an approach can, among other things, facilitate a consistent sealing interface between the flaps and the housing when the air extractor is in a sealing position.
With reference to
With reference now to
The pressure differential causes the air extractor 10 to move to a flow permitting position where a flow F of air from the passenger compartment 14 can move through an opening in the air extractor 10 to the exterior of the vehicle. Permitting the flow F through the air extractor 10 can lower the pressure PINT. After the pressure PINT is substantially equal to the pressure PEXT, the air extractor 10 returns to the sealed position of
With reference now to
The exemplary flaps 24 are free floating and passively controlled. A rise in the pressure PINT relative to the pressure PEXT forces the flaps 24 to move from the sealed position of
In this example, the seal 28 is compressed against the body panel 12 of the vehicle to block flow from moving between the body panel 12 and an outer perimeter of the air extractor 10. The perimeter seal 28 blocks such flow when the flaps 24 are in the sealed position and when the flaps 24 are in the flow permitting position.
In the position of
Due to the pressure differential, the flow F moves against the flaps 24, which causes the flaps 24 to move from the flow blocking position to the flow permitting position. When the pressure PINT is substantially equal to the pressure PEXT, the flaps 24 fall back to the sealed position of
As can be appreciated, dimensional inconsistencies in the housing 20 and the flaps 24 near the interfaces 44 could result in gaps between the housing 20 and the flaps 24 at the interfaces. Inconsistencies could include waviness in the flaps 24, flash, etc. The gaps can provide undesirable passageways for contaminants.
To address inconsistencies, the flaps 24 are molded against the housing 20 in the sealed position of
When molding the flaps 24 in the sealed position each of the flaps 24 is molded such that the flaps 24 directly contacts the housing 20 at the hinged connections 30 and directly contacts an edge of the housing 20 at the interface 44. The hinged connections 30 and the edges of the housing 20 providing the interface 44 are on opposite sides of the opening 36.
To avoid the flaps 24 bonding to the housing 20 during molding, the flaps 24 have a material composition that differs from a material composition of the housing 20. The flaps 24 can thus be molded against the housing 20 in the sealing position without the flaps 24 covalent to bonding to the housing 20.
With reference now to
The material composition M1 is, in one example, a polymer-based material such as a thermoplastic polymer, like polypropylene, or an Olefinic Thermoplastic Elastomer (TEO). The material composition M1 could include a talc fill, such as a 40% talc fill.
The method then moves to the step shown in
The seal 28 has a material composition M2 that can differ from the material composition M1. For example, the seal 28 could be a thermoplastic elastomer (TPE) having olefins. However, unlike the flaps 24, the material composition M2 of the seal 28 can be compatible with the material composition M1 of the housing 20 such that the seal 28 bonds to the housing 20 as the seal 28 cures within the mold 60. In some examples, the seal 28 is covalent bonded to the housing 20 during the molding. Dipole-dipole bonds, dispersion bonds, or both could be used to secure the seal 28 to the housing 20 during molding.
Next, as shown in
If, for example, a transfer molding method is used, the housing 20 can be molded outside the mold 60, and then placed within the mold 60. If, for example, a rotary molding method is used, the housing 20 can be molded in a portion of the mold 60, say, half of the mold. Next, the portion of the mold 60 and the housing 20 are rotated to a position interfacing with the remaining portions of the mold 60. The material M3 is then injected to form the flaps 24.
In this example, the air extractor 10 includes two flaps 24. Other examples could include more flaps 24, or a single flap 24.
The flaps 24 are each hingedly connected to the housing 20 in this example. The hinged connection results from the flaps 24 including a portion 66 that circumferentially surrounds a pin 70 of the housing 20. When the flaps 24 move between the sealing position and the flow permitting position, the flaps 24 pivot about the pin 70 of the housing 20.
With reference to
The flap 24a can move relative to the housing 20 between the sealing position and the flow permitting position without the enlarged area 74 withdrawing through an opening 82 in the housing 20 while still permitting the flap 24a to move back and forth between a flow permitting position and a sealing position.
Features of the disclosed examples include molding a flap of an air extractor in a sealing position relative to a housing to, among other things, address waviness, flash, and other features that could introduce gaps or complicate movement of the flaps relative to the housing. The flaps are also hingedly connected to the housing during the molding, which can simplify assembly. The air extractor molded according to the disclosed examples can help to meet climate control low flow requirements for window fogging.
The preceding description is exemplary rather than limiting in nature. Variations and modifications to the disclosed examples may become apparent to those skilled in the art that do not necessarily depart from the essence of this disclosure. Thus, the scope of legal protection given to this disclosure can only be determined by studying the following claims.
