1. Field of the Invention
The present invention relates generally to sunshades for vehicles, and in particular, to a mounting bracket assembly that allows the sunshade to be installed in a vehicle without the use of tools or fasteners.
2. Description of the Related Art
Sunshades for vehicles are typically mounted on the vehicle body roof by a bracket assembly that provides both a horizontal axis about which a visor blade pivots between a storage position adjacent the vehicle headliner and a use position adjacent the windshield, and a generally vertical axis about which the visor pivots between a forward windshield position and a side window position. The need to use fasteners and tools, either powered or hand driven, in the installation into vehicles of many existing sunshade mounting bracket assemblies is undesirable for a number of reasons. For example, in addition to diminishing the aesthetics of the finished product, fasteners may be more labor intensive to install and therefore more expensive to employ. In addition to being costly, fasteners may also be potentially damaging to the vehicle.
A variety of sunshade mounting bracket assemblies have been developed, such as those disclosed in U.S. Pat. No. 5,062,608 and U.S. Pat. No. 5,242,204, which substantially dispense with the need for tools and fasteners in installation. However, while perhaps facilitating installation in some respects, these assemblies are not without their shortcomings.
For example, shortcomings with existing designs pertain to the effort or torque required to swing the sunshade between a windshield covering position and a side window covering position. The required rotational effort is typically a function of the frictional resistance between the bracket assembly elbow and the remainder of the mounting bracket assembly. Prior art attempts to control this effort have taken numerous forms. As disclosed in U.S. Pat. No. 5,242,204, springs have previously been used to try and force mating parts together to provide an adequate frictional engagement therebetween. However, the use of springs may increase the expense of the component parts and complicate the assembly of the parts.
Other designs, such as in U.S. Pat. No. 5,031,954, utilize an interference fit between an elbow or bracket arm and a bracket, wherein the elbow is held within the bracket by an engagement of an elbow head by tangs of the bracket.
In response to these shortcomings a visor mounting bracket assembly having a desired rotational effort that does not require springs to produce the effort and which can provide a substantial effort without hindering installation was developed and is disclosed by U.S. Pat. No. 5,499,854, which is expressly incorporated by reference herein. The visor mounting bracket assembly of U.S. Pat. No. 5,499,854 does not require fasteners or tools to install and provides a stable bracket assembly which is not likely to have its rotatability adversely affected by vibrations experienced during use. It is desirable to further improve the characteristics of this design.