Patent Application
20060006568
1. Field of the Invention
The invention relates to a method of making an interior vehicle part, such as a grab handle.
2. Background Art
A prior method of making a grab handle involves positioning a metal bracket in a mold and injection molding plastic material around the bracket. Because the plastic material is typically rigid, the grab handle does not have a soft feel.
A prior method of making a vehicle arm rest involves injection molding a plastic substrate in a first mold and roto-casting a cover layer or skin in a second mold. A bracket may also be inserted into the first mold during formation of the substrate, and the substrate may be molded directly onto the bracket. Moreover, the skin may be painted after the roto-casting process to achieve a desired color and gloss. The substrate and skin are then positioned in a third mold such that the substrate and skin are spaced apart from each other. Expandable foam is then introduced between the substrate and skin.
Because multiple molds are involved in the above method, tooling costs are significant. Furthermore, because the components must be transferred from one mold to another, the method may be time consuming to implement.
Under the invention, a method of making an interior vehicle part for use with a motor vehicle is provided. The method includes the steps of spraying material proximate a surface of a mold portion of a mold to form a skin layer, the surface defining a mold cavity of the mold portion; positioning an insert proximate the mold cavity, the insert being configured for attachment to the vehicle; and introducing material into the mold cavity to form a foam layer that contacts the skin layer and the insert.
The substrate 12 may comprise any suitable foam material. For example, the substrate 12 may comprise an elastomer such as expanded polyurethane. Furthermore, the density of the substrate 12 is preferably, but not necessarily, in the range of 0.024 to 0.19 grams per cubic centimeter (g/cm3). Advantageously, the substrate 12 may be configured to provide the grab handle 10 with a soft feel.
The substrate 12 may also be substantially thicker than the skin layer 14 and coating 16 combined. Alternatively, the substrate 12 may have any suitable thickness.
The skin layer 14 is adhered to the substrate 12 and coating 16. Moreover, the skin layer 14 is configured to provide a resilient covering over the substrate 12 and may comprise any sufficiently dense material. For example, the skin layer 14 may be a solid layer that comprises an aromatic or aliphatic compound. As a more specific example, the skin layer 14 may be made of an elastomer such as polyurethane. Furthermore, the skin layer 14 may have any suitable thickness and density. For example, the skin layer 14 may have a thickness in the range of 0.3 to 10 millimeters (mm), and a density in the range of 0.15 to 1.5 g/cm3. In one embodiment of the invention, the skin layer 14 has a thickness in the range of 0.8 to 1.2 mm.
The coating 16 may be used to protect the skin layer 14 and/or to provide a decorative surface for the grab handle 10. For example, the coating 16 may be used to inhibit sunlight or other ultraviolet light from reaching the skin layer 14. As another example, the coating 16 may be used as a paint to provide a desired color or texture to the grab handle 10. While the coating 16 may comprise any suitable material, in one embodiment of the invention the coating 16 is made of an aliphatic polyurethane composition. Furthermore, the coating 16 may have any suitable thickness, such as a thickness in the range of 0.5 to 1.5 mils.
Alternatively, the coating 16 may be omitted if not required for a particular application. For example, the skin layer 14 may be configured to provide a sufficiently durable and attractive surface such that the coating 16 is not needed.
The insert 18 may have any suitable configuration sufficient for attachment to the vehicle 11. For example, the insert 18 may include attachment features, such as clips 20, that are engageable with a panel of the vehicle. Furthermore, the insert 18 may be made of any suitable material such as plastic or metal.
Referring to
The method begins by spraying a mold release agent on each mold surface 28 and 32. Next, referring to
Next, referring to
As mentioned above, the coating 16 may be omitted from the grab handle 10. In such a case, the skin layer forming material may be sprayed directly onto the mold surfaces 28 and 32, or onto a mold release agent that is applied on the mold surfaces 28 and 32, to form skin layers 44 and 46.
The method then includes positioning insert 18 proximate one of the mold portions 23 and 24. For example, each mold portion 23 and 24 may have a positioning feature or locator, such as a groove 51, for receiving the insert 18. In the embodiment shown in
Next, referring to
Furthermore, the foam forming material may be applied on each skin layer 44 and 46 when the mold 22 is in the open position, such that a first foam layer 56 is formed on the first skin layer 44 and a second foam layer 58 is formed on the second skin layer 46. With this approach, the mold 22 may then be moved to the closed position shown in
Alternatively, the foam forming material may be sprayed or otherwise injected into the mold cavities 30 and 34 when the mold 22 is in the closed position, thereby forming the substrate 12. Under this approach, the mold 22 may be provided with one or more suitable injection passages (not shown) for introducing the material into the mold cavities 30 and 34.
When the mold 22 is moved to the closed position, the skin layers 44 and 46 cooperate to form the skin layer 14, and the coatings 36 and 38 cooperate to form the coating 16. Furthermore, the skin layers 44 and 46 may bond to each other, and the coatings 36 and 38 may also bond to each other, when the mold 22 is in the closed position.
Under the invention, a single mold may be used to form the grab handle 10, or other interior vehicle part. Thus, the method of the invention involves less tooling than prior art methods in which components are formed in separate molds.
Examples of other vehicle parts that may be made by the above method include arm rests and rollover bars.
Although separate spray assemblies 40, 48 and 52 are shown in the Figures, the spray assemblies 40, 48 and 52 may be provided as a single spray assembly that is configured to spray all of the above described materials. Furthermore, if the material to be sprayed includes multiple substances, the substances may be mixed at any suitable time. For example, the substances may be mixed upstream of, within, or downstream of associated spray heads.
While embodiments of the invention have been illustrated and described, it is not intended that these embodiments illustrate and describe all possible forms of the invention. Rather, the words used in the specification are words of description rather than limitation, and it is understood that various changes may be made without departing from the spirit and scope of the invention.
