1. Technical Field
The present disclosure relates to coupling a throttle body with an intake manifold.
2. Background Art
Automotive throttle bodies have a flange for coupling with a flange located on an inlet side of an intake manifold. Typically the throttle body is metallic, possibly of aluminum, with a metallic throttle plate pivoting inside. Modern intake manifolds are injection molded of a polymeric material. The coupling between the two are shown in
To allow for coupling of the two parts in spite of manufacturing tolerances and to allow the bolts to be easily inserted, through holes 18 are slightly oversized. The inside diameters of throttle body 10 and intake manifold 12 may be offset slightly due to the slight oversize of the inside diameters of throttle body 10 and other manufacturing tolerances. The mismatch is shown in
According to an embodiment of the disclosure at least two sets of locator pins are provided on the flange of the intake manifold which couple with orifices provided on the flange of the throttle body. In addition, through holes are provided on the throttle body flange and threaded inserts are provided on the flange of the intake manifold. The locator pins are coupled with the orifices prior to inserting a bolt through the through holes to engage with the threads of the threaded insert. By providing the locator pins, the two flanges are held in a desired orientation so that the ducts of the two flanges are properly aligned to substantially eliminate a step at the interface.
In one embodiment, a throttle body-to-manifold coupling system has a first flange coupled to the throttle body, a second flange coupled to the manifold, a set of locator pins extending outwardly from the second flange, and an orifice provided on the first flange for the set of locator pins. The set of locator pins and the associated orifice are arranged to couple when the manifold is assembled to the throttle body. An inside diameter of the first flange is substantially equal to an inside diameter of the second flange. The second flange further comprises at least three threaded inserts arranged on the periphery of the second flange. The first flange has a through hole associated with each of the at least three threaded inserts. A bolt associated with each of the at least three threaded inserts is inserted through the through hole and engaged with threads on the threaded insert. The locator pins extend outwardly from the second flange approximately perpendicular to a face of the second flange. A cross section of each set of locator pins in a plane parallel to a face of the flange is contained within a cylinder having a diameter substantially equal to a diameter of the orifice. The intake manifold, the flange of the intake manifold, and the locator pins are comprised of a polymeric, elastic material. In one embodiment, the set of locator pins is arranged on the flange along an axis roughly perpendicular to the axis of the pin associated with the throttle valve. This location locates the intake manifold with respect to the throttle body in the area in which a mismatch or step is more problematic. In other embodiments, two or more sets of locator pins with associated orifices are provided. In such an embodiment, the sets of locator pins may be place around the flange asymmetrically to prevent misassembly.
The first flange defines a central opening and the sets of locator pins are asymmetrically arranged on a periphery of the second flange with respect to the opening. The first flange has a roughly centrally-located first opening of a particular diameter; the second flange has a roughly centrally-located second opening of the particular diameter; and the first and second openings are substantially aligned when the locator pins and the associated orifices are coupled. Each set of locator pins comprises at least two locator pins. In one embodiment, the cross-sectional area of the locator pins is roughly constant along their length except at a distal end of the locator pins that has a slight chamfer with the chamfer located away from the other pins of a set of locator pins. In an alternative embodiment, the pins are tapered with the cross-sectional area of the pins being larger proximate the flange.
By using a set of locator pins of an elastic material, the pins can flex to facilitate the alignment and coupling of the pins with the orifices. Also, the chamfers assist in the alignment. As the locator pins are fully engaged with the orifices, however, the pins provide little or no flexibility in alignment and force the throttle body into proper alignment with the intake manifold. Such a system provides an advantage over coupling systems relying solely on the through holes in the throttle body for alignment.
Also disclosed is a method to couple a throttle body to an intake manifold, including aligning a set or sets of locator pins that extend outwardly from a flange on the intake manifold with orifices defined in a flange on the throttle body; engaging the locator pins with the orifice(s); inserting bolts into through holes in flanges associated with the throttle body; engaging threads on the outside surface of the bolts with the threads on the inside surface of the threaded inserts; and tightening the bolts to provide a desired clamping force between the throttle body and the intake manifold. The sets of locator pins are arranged around the periphery of the flange on the intake manifold possibly asymmetrically arranged. The locator pins extend outwardly from the flange associated with the intake manifold from a face of the flange adapted to couple with the flange on the throttle body with an axis of the locator pins being roughly perpendicular to a surface of the flange on the intake manifold. The cross-sectional area of the locator pins is roughly constant along the length except at a distal end of the locator pins that has a slight chamfer.
Not only do the locator pins align the central openings in the two flanges, but they also aid in the assembly of the intake manifold with the throttle body by holding the two together while the bolts are inserted and tightened.
As those of ordinary skill in the art will understand, various features of the embodiments illustrated and described with reference to any one of the Figures may be combined with features illustrated in one or more other Figures to produce alternative embodiments that are not explicitly illustrated or described. The combinations of features illustrated provide representative embodiments for typical applications. However, various combinations and modifications of the features consistent with the teachings of the present disclosure may be desired for particular applications or implementations. Those of ordinary skill in the art may recognize similar applications or implementations consistent with the present disclosure, e.g., ones in which components are arranged in a slightly different order than shown in the embodiments in the Figures. Those of ordinary skill in the art will recognize that the teachings of the present disclosure may be applied to other applications or implementations.
An end view of flange 50 associated with an intake manifold is shown in
In one embodiment, the face of tabs 56 is roughly coincident with the face of flange 50. Alternatively, the face of tabs 56 is recessed with respect to the face of flange 50 and will be discussed further in reference to
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In one embodiment locator pins are provided on the flange of the intake manifold. In another embodiment, the locator pins are provided on tabs extending outwardly from the normal boundaries of the intake manifold flange. In yet another embodiment, the tabs that extend outwardly from the intake manifold flange are recessed. An example of such a configuration is shown in
While the best mode has been described in detail, those familiar with the art will recognize various alternative designs and embodiments within the scope of the following claims. Where one or more embodiments have been described as providing advantages or being preferred over other embodiments and/or over prior art in regard to one or more desired characteristics, one of ordinary skill in the art will recognize that compromises may be made among various features to achieve desired system attributes, which may depend on the specific application or implementation. These attributes include, but are not limited to: cost, strength, durability, life cycle cost, marketability, appearance, packaging, size, serviceability, weight, manufacturability, ease of assembly, etc. The embodiments described as being less desirable relative to other embodiments with respect to one or more characteristics are not outside the scope of the disclosure as claimed.