1. Field of the Invention
The present invention relates to a vehicle sunshade device constructed such that an opening formed in a roof of a vehicle is opened and/or closed by a sunshade for shielding a passenger compartment of the vehicle from sunlight, and more particularly to a construction for guide rails for guiding the sunshade.
The present application is based on Japanese Patent Application No. Hei. 10-167378 and No. Hei. 10-167379, which are incorporated herein by reference.
2. Description of the Related Art
A conventional sunshade device such as fitted on a roof of, for example, a van comprises a sunshade disposed under a light-transmissive sunroof lid for opening and/or closing a opening formed in a roof of the van for shielding a passenger compartment of the van from sunlight, and guide rails for longitudinally slidably supporting the sunshade.
The sunshade can move between a fully closed position where it closes the opening under the sunroof lid and a fully opened position where it is stored in a storing portion formed between the ceiling of the passenger compartment and the roof of the van. The guide rails each have a guide groove for guiding the sunshade along a desired locus and in which sliding members are slidably fitted which can elastically be deformed in vertical directions and are provided on both sides of the sunshade at front and rear ends thereof. The guide grooves each have a front straight portion, a rear straight portion positioned vertically higher than the front straight portion and a inclined portion disposed between the front and rear straight portions and inclined moderately upwardly toward the rear. The sunshade is stored in the storing portion while being displaced upwardly when the sliding members are moved from the front straight portions to the rear straight portions via the inclined portions (refer, for instance, Japanese Utility Model Publication No. Hei. 3-70515).
With the conventional sunshade described above, for instance, when the sunshade is moved from the fully closed position to the fully opened position, with the rear sliding members entering the inclined portions, the sunshade is displaced upwardly at a rear end thereof, when the front sliding members are guided by the front straight portions so as to move horizontally therealong. This causes a difference in locus along which the front and rear sliding members move, and the deflection amount of the rear sliding members is changed at the inclined portions, the sliding operation force for the sunshade thereby becoming unstable. Thus, there is caused a problem that no smooth sliding operation of the sunshade can be obtained.
Further, a certain type of sunroof device is provided with two front and rear sunshades for shielding a passenger compartment of the vehicle from sunlight.
In a sunshade device of this type, when the opening is closed, the front and rear sunshades are disposed substantially on the same horizontal plane with a rear end of the front sunshade and a front end of the rear sunshade abutting with each other, and when the front sunshade is slid rearward from the above state, the rear sunshade is pushed rearward, and after the rear sunshade is stored in a storing portion formed in a lower portion of the roof, the abutment relationship between the front and rear sunshades is released. Thereafter only the front sunshade is moved alone further rearward, and in a fully opened state, the front sunshade and rear sunshade are stored in the storing portion with the former being stacked above the latter in a one-on-the-other fashion (refer, for instance, Japanese Utility Model Publication No. Hei.5-60919).
With a conventional sunshade device as described above, however, in the fully opened state, the front and rear sunshades are disposed vertically with a certain gap being maintained therebetween, and this may cause a risk of producing a looseness of the two sunshades so disposed.
In order to eliminate such a risk, there is proposed a design in which a leaf spring is provided in a storing portion for two sunshades so as to bias a rear sunshade upwardly (refer, for example, to Japanese Patent Publication No. Hei.5-24437). However, in this sunshade device, both of front and rear sunshades are biased upwardly by the leaf spring, it should be necessary to prepare a large and strong leaf spring, and there is a risk that front and rear sunshades are rubbed with each other, so skin materials thereof are damaged.