JPS60219166A - Reinforce structure of synthetic resin lid for car - Google Patents

Abstract

PURPOSE:To provide high torsional rigidity to synthetic resin lid with reduced number of ribs by projecting two diagonally extending ribs and quadrilateral ribs sequentially coupling between the centers of adjoining sides from the inner face of lid. CONSTITUTION:Striker fixing section 3 to be fixed dismountably to the chassis is provided at the front end of bonnet 2 while hinges 6, 6 for hinging the bonnet 2 to the chassis is provided at the rear end. Single or plural ribs 7, 7 extending along two diagonal lines and single or plural quadrilateral ribs 8 coupling sequentially between the centers of adjoining sides are formed integrally together with the bonnet 2 where said ribs 7, 7 and 8 will cooperate to improve the torsional rigidity of bonnet.

Description

Detailed Description of the Invention A0 Object of the Invention (1) Industrial Application Field The present invention relates to synthetic resin lids for automobiles such as bonnets and trunk lids, particularly synthetic resin m for automobiles whose basic shape is quadrilateral. Regarding the reinforcing structure of the lid.

(2) Prior Art It is already known to mold automobile lids from synthetic resin, as described in Japanese Utility Model Publication No. 44-7602 and Japanese Unexamined Patent Publication No. 56-60776.

This type of lid generally has the advantage of being lighter than one made of steel plate, but is inferior in rigidity.

Therefore, as described in the above-mentioned publication, conventional products have a plurality of ribs protruding from the inner surface of the lid to increase the rigidity of the lid. No efficient reinforcement structure has been developed to increase stiffness.

(3) Problems to be Solved by the Invention An object of the present invention is to provide an efficient reinforcing structure capable of imparting a large torsional rigidity to a synthetic resin lid using as few ribs as possible.

B1 Structure of the Invention (1) Means for Solving Problems According to the present invention, the reinforcing structure includes, on the inner surface of the lid, diagonal ribs extending along two diagonal lines of the lid; It is constructed by protruding quadrilateral ribs extending so as to sequentially connect substantially midpoints of adjacent sides of the lid.

(2) Function The diagonal ribs extending along the two diagonal lines of the lid and the quadrilateral ribs extending sequentially to connect substantially midpoints of each adjacent side of the lid are made of synthetic resin. To efficiently impart torsional rigidity to a manufactured lid.

(3) Example One example of the present invention will be explained with reference to drawings.
In the figure, a car 1 has a hood 2 as a lid.
is equipped, and this bonnet 2 is made of synthetic resin, such as SM
'Made from C material.

As shown in Figure 2, the bonnet 2 has a basic rectangular shape with its long sides facing in the left-right direction of the vehicle, with the front side slightly curved outward and the rear side curved largely inward. , the center part of the front side becomes a striker attachment part 3, and both end parts of the rear side become a pair of hinge attachment parts 4, 4. A striker 5 for detachably fixing the front end of the bonnet 2 to the vehicle body is attached to the striker attachment portion 3, and the rear end of the bonnet 2 is hingedly connected to the vehicle body to the hinge attachment portions 4, 4. A hinge 6.6 for each is attached.

On the inner surface of the bonnet 2, there are diagonal ribs 7.7 extending along the two diagonal lines of the bonnet 2, and diagonal ribs 7.7 extending in parallel with each other or in parallel. One or more quadrilateral ribs 8 extending in parallel are provided in a protruding manner, and these ribs 7.8 are integrally molded with the bonnet 2.

Thus, the diagonal ribs 7.7 and the quadrilateral ribs 8 cooperate to efficiently increase the torsional rigidity of the bonnet 2. This was confirmed by the following test.

First, the following first to fifth test products a to C (see FIG. 3) are prepared. - - First test product a: A synthetic resin bonnet 2 with protruding diagonal ribs 7.7 and one quadrilateral rib 8 on the inner surface of the synthetic resin bonnet 2 according to the present invention.

・Second test product h: A peripheral rib 10 with one rib on the front side and two parallel ribs on the remaining three sides protruding from the inner surface of the synthetic resin bonnet 2.

・Third test product C: A synthetic resin bonnet 2 with a negative peripheral rib 10 and two vertical ribs 11 and two horizontal ribs 12 extending orthogonally in a lattice pattern.

- Fourth test product d: A synthetic resin bonnet 2 with one peripheral rib 10 and each diagonal rib 7.7 protruding from the inner surface.

・Fifth test item e: On the inner surface of the synthetic resin bonnet 2, - peripheral ribs 10 and two parallel diagonal ribs 7.7
It has a protruding .

In addition, for each test product, the size of the bonnet 2 is 12 mm in width.
The size of the rib is 15m x 1.8mm in height and 1.8mm in thickness.

Next, as shown in Figure 4, each of the test specimens a to e was fixed to the test stand at three points (black circles in the figure): one end of the front side of the bonnet 2 and both ends of the rear side. A vertical load F was applied to the remaining free end to cause a deflection of 1 mm, and the magnitude of the load F at that time was investigated, and the results shown in the graph of FIG. 3 were obtained.

The graph in Figure 3 has 1 load on the vertical axis and 1 lip factor on the horizontal axis, so a large value on the vertical axis indicates a high torsional rigidity of the bonnet 2, and a large value on the horizontal axis indicates a high torsional rigidity. This shows that the weight increase rate of the bonnet due to the ribs is large. Therefore, if the value on the vertical axis is small and the value on the horizontal axis is small, it means that the torsional rigidity is efficiently reinforced by the ribs.

Incidentally, the "lip factor" is calculated from the following formula.

As a result of the above test, the first test article α according to the present invention was
Compared to the fifth test specimens b to e, it showed a much larger value on the vertical axis and a much smaller value on the horizontal axis. From this, it can be seen that the reinforcing structure according to the present invention contributes to efficiently strengthening the torsional rigidity of the bonnet 2.

Returning to FIG. 2 again, the bonnet 2 further includes one or more peripheral ribs 15 extending along the four sides of the bonnet 20, and a plurality of diagonal lattice lips 16 connected to the peripheral ribs 15. These ribs 15, 16 mainly contribute to increasing the surface rigidity of the bonnet 2.

C0 Effects of the Invention As described above, according to the present invention, by the cooperation of the diagonal ribs extending along two diagonal lines and the quadrilateral ribs extending sequentially to connect substantially midpoints of each adjacent side of the lid, The torsional rigidity of the synthetic resin lid has been efficiently increased.
A small amount of ribs can provide a large amount of torsional rigidity to the lid. Therefore, the torsional rigidity can be sufficiently increased without sacrificing the inherent lightweight advantage of synthetic resin lids. This is to prevent distortion as much as possible in such products and improve its marketability.

[Brief explanation of the drawing]

Fig. 1 is a perspective view of an automobile to which the present invention is applied to the bonnet, Fig. 2 is a bottom view of the bonnet, and Fig. 3 is a graph showing the results of torsional rigidity tests of various test products. The test products h to e are comparative test products, and FIG. 4 is an explanatory diagram of the above test method.

Claims (1)

[Claims] A reinforcing structure for a synthetic resin automobile lid whose basic shape is a quadrilateral, wherein the inner surface of the lid includes diagonal lips extending along two diagonal lines of the lid, and each adjacent side of the lid. A reinforcing structure for synthetic resin ribs for automobiles, which is formed by protruding quadrilateral ribs that extend so as to sequentially connect substantially midpoints of the ribs.