1. Field of the Invention
The present invention relates to a fixation method of a hinge point of a tailgate for an automobile, and more particularly to a fixation method of a hinge point of a tailgate for an automobile adapted to improve a difficulty of fixing a hinge point due to a difference between a central roof panel and a hinge point of an outer block when a tailgate is mounted.
2. Description of the Prior Art
Generally, a vehicle is mounted with a plurality of doors openable and closeable for loading and unloading and in case of a one-box car such as a jeep, one-ton a van, etc., a tailgate is arranged at a rear side thereof for loading and unloading of cargoes.
The tailgate is hinged, as illustrated in FIGS. 2 and 3, to a left hinge Hxe2x80x2 and a right hinge Hxe2x80x3 about a central line C of roof panel R for possible rotation.
The roof panel R of the vehicle forms a predetermined shape of curvature, and due to a difference of central mounting position between the left hinge Hxe2x80x2 and the right hinge Hxe2x80x3, a rotating center for the hinges Hxe2x80x2 and Hxe2x80x3 should be fixed and interference from the roof panel R should be precluled when a tailgate T is rotated.
At this point, the left hinge Hxe2x80x2 indicated in a dotted line in FIG. 3 is to fix a hinge positioned in the left elevation, as projected on a central line position for the convenience of illustration.
Now, a fixing method of hinge point for the tailgate T will be described. When a parting line for the roof line R and the tailgate T is determined at a design stage which is an initial development state of a vehicle, a design part seeks a hinge point of the tailgate T. At this time, a worker imaginarily fixes an imaginary hinge point and simulates thereon.
When the simulation is performed, checks are made into whether or not there exists an interference of parting line of the roof panel R and the tailgate T, state of gap set-up, etc., and if the interference occurs, the hinge point is changed to repeat the simulation.
Of course, while a designer of the tailgate T repeats the above-mentioned simulation, a roof panel designer should wait for the completion of the work by the designer of tailgate T, not performing the design of the roof panel R.
However, there is a problem in that, when a hinge point of a tailgate is designed as mentioned above, and if a random point is set up to simulate rotation of the tailgate and the like and to check the interference, state of gap set-up and the like, and above-mentioned processes are repeated until above mentioned respective values reach points within design values, operation rates are decreased dramatically.
Furthermore, a hinge point design efficiency of the tailgate becomes very low, a design operation of roof panel where the above mentioned hinge point is situated is delayed, to thereby decrease the entire design efficiency of a vehicle.
The present invention is provided to solve the aforementioned problems and it is an object of the present invention to provide a fixation method of a hinge point of a tailgate for an automobile adapted to fix a hinge point of a tailgate for an automobile within a fast period of time and to rule out an interference from a tailgate parting line and a roof panel parting line.
In accordance with the objects of the present invention, there is provided a fixation method of a hinge point of a tailgate for an automobile, the method comprising the steps of:
drawing line segments G1 and G2, each detached at a predetermined distance from a central parting line P1 of the roof panel, and fixing a circle C1 having the same curvature as the curvature R of the central parting line P1 so as to define G1 as tangent;
fixing the circle C1 to seek a cross point I1 with the line G2 and fixing a straight line segment L1 connecting the cross point I1 with a parting line P2 of the tailgate;
fixing a circle C2 designating the straight line segment L1 as diameter; and
fixing a straight line segment L2 dividing and orthogonally crossing the circle C2 and the straight line segment L1 to fix a cross point I2 with the circle C2 at the tailgate side and to fix the cross point I2 as a hinge point.