US 3519327 A
Description (OCR text may contain errors)
July 7 1970 ToYoTsucH'l NAKAJIMA 3,519,327
LIGHT-REFLECTING BODY FOR TRAFFIC INDICATION Filed Jan. 17, 1968 2 Sheets-Sheet 1 Sig/(3.
BY w www July 7, 1970 TOYoTsUcHi NAKAJIMA 3,519,327
LIGHT-REFLECTING' BODY FOR TRAFFIC INDICATION Filed Jan. 17, 1968 2 Sheets-Sheet 2 INVENTOR. TOYOTSUGH: NHKHJ/Mn United States Patent Office 1m. cl. Gbzb 5/.12
U.S. Cl. 350--97 1 Claim ABSTRACT F THE DISCLOSURE A light-reflecting body for traflic indication wherein, when light is projected onto said light-reflecting body from the headlight of an automobile in a wide range of lateral and sidelong angles, it can be rellected back to the driver in an accurate and effective manner.
BRIEF SUMMARY OF THE INVENTION This invention relates to a light-reilecting body for traffic indication, consisting of a transparent body formed 'with an inclined, light-refracting plane inclined for a predetermined angle or less against a horizontal surface, a horizontal light-reflecting plane for reflecting said refracted light and a plurality of upright planes interesecting said horizontal light-reflecting plane at right angles and being capable of reflecting said light reflected by said horizontal light-reflecting plane once respectively and a zigzag-shape surface formed by said upright light-rellecting planes while intersecting each other at right angles.
The object of the present invention can be achieved exactly by the mechanism of said light-reflecting body for traffic indication, in that an inclined, light-rellecting plane and a horizontal light-reflecting plane, as mentioned above, can act as a light-refracting plane and a light-reflecting plane respectively common to the upright surfaces of a plurality of said upright light-reflecting planes intersecting each other at right angles and forming said zigzag-shape surface.
BRIEF DESCRIPTION OF THE DRAWINGS Of the accompanying drawings to illustrate the present invention, FIG. l is a plan view showing an embodiment of the light-reflecting body for trafic indication. FIG. 2 is a cross sectional View of the same, taken along the line A-A of FIG. 1. FIG. 3 is a cross sectional view of the same, taken along the line B-B of FIG. l. FIG. 4 is a perspective View to show the characteristics and action of the light-reflecting body, according to the present invention.
DETAILED DESCRIPTION The present invention relates to a light-reflecting body for traffic indication, consisting of a transparent body 7 formed with an inclined light-refracting plane 3 inclined for a predetermined angle or less against a horizontal surface, a horizontal light-reflecting plane 4 and a zigzag- `shape surface consisting of a plurality of upright, light-re' ilecting planes and 6 intersecting said horizontal lightreflecting plane at right angles for reflecting said reflected light once respectively while intersecting themselves at right angles. By the way, reference 1 is a transparent external body and 2 is an internal filler.
In order to work out the substantials of the present invention, as shown in FIG. 4, the geometrical properties of a basic form thereof will be shown as follows.
Referring to FIG. 4, the following formulae will be self-explanatory.
3,519,327 Patented July 7, 1970 (4) ABlClDl, A`B2C2D2AB3C3D3 are understood to form an inclined light-reilecting plane 3.
AAlClDl, AA2C2D2AA3C3D3 are understood t0 form a horizontal light-reflecting plane 4.
(6) A1B1E1F1, ElAzBaEaFz, IAsBsEsFa derstood to form surfaces 5 and 6.
are llIl' Therefore, the characteristics of the light-rellecting body of the present invention consist in providing an inclined light-refracting plane 3 and a horizontal lightreflecting plane 4 against light-rellecting zigzag-shape surfaces 5 and 6.
In the horizontal light-reflecting plane,
(as shown in FIG. 4), the planes C2F2D1, C3F3D2, C4F4D3, C4F4D3, C5F5D4, and C5F6D5 remain in the horizontal light-reflecting plane and are utilized repeatedly as part thereof so that the horizontal light-reflecting plane may serve as a whole light-reflecting plane wider in extension than actually in itself.
The invention will be explained in detail with reference to the accompanying drawings.
When the light-reflecting body is placed, for example, on the center line of surface of the road, light projected from the headlight of an automobile will enter the transparent body 7 from the inclined light-refracting plane 3 by refraction and is subsequently reflected by the horizontal light-reflecting plane 4 and the upright light-rellecting planes 5 or 6, or 6 or 5 once respectively and the reflected light is retracted back by the inclined lightrefracting plane 3 to proceed outwardly through the transparent body 7 so that it can be reflected back in the direction of the headlight of the automobile to reach the eye of the driver.
In the light-reflecting body of the present invention, said inclined light-refracting plane 3 and horizontal lightreflecting plane 4 are provided in such a manner that they are placed respectively common to a plurality of said upright light-reflecting planes 5 and 6 and therefore in the case of light coming from an extremely small inclined angle, a in the longitudinal direction of the road, namely, from the headlight of an automobile very far, it can be reflected lback to the driver accurately. Moreover, in the case of light coming from a large angle of sidelong inclination, 58, for example, less than 45 to the right and left in the lateral direction of said light against the light-reflecting body, it can also be reflected back to the driver satisfactorily. Thus all light onto said inclined light-reflecting plane 3 can be reflected back efficiently so far as it remains within the limits of said angles of inclination, a and 13.
Now referring to FIG. 4, the optical properties of the light-reflecting body of the present invention will be explained in detail.
When the light l1 is projected onto the light-reflecting lbody, the following processes will be made.
(l) The light is retracted at the point a on the plane of ABsCsD, i.e. the light-refracting plane 3.
(2) Then it is reflected at the point b on the plane of AACD, i.e. the horizontal light-reflecting plane 4.
(3) Then it is further reflected at the point of c on the plane of [jABEql-Tq.
(4) Then it is still further reflected at the point of d on the plane 6 of EA6B6E6F6.
(5) Finally, it is retracted at the point of e on the plane of AB6C6D6, i.e. the inclined light-refracting plane 3 so that it can come out as the reflected light l2 in parallel with said light l1 for return to the light source.
Thus, in case the light l2 is a projected light, l1 as a reflected light will be reflected back to the light source While advancing in the opposite direction'on the same processes. In this manner, the strong point of the present light-reflecting body consists in the fact that when the projected light l1 or l2 assumes a small angle o with the horizontal plane, the horizontal angle of said light against the plane defined by the central line ASG and the line ASB., passing through the point of A6 on AAGCGDG is found to be less than 45, and said light remains projecting said inclined plane 3, it can be reflected `back always efliciently in the direction of the light source.
In other words, in the case of the light projected from the headlight of an automobile very far from the lightreflecting body, namely, assuming a small inclined angle 1 of sidelong inclination against the horizontal plane, it can be reflected back to the light source also satisfactorily.
Moreover, in the case of the light-reflecting body is placed on the center line of the road, all light projected from the headlight of an automobile travelling at a pretty large angle 13 against the center line, will be reflected back provided that such angle remains less than 45.
What is claimed is:
1. A roadway marker arranged to be supported on a roadway surface for reflecting light back to a motor vehicle, comprising a transparent external member having a downwardly directed interior recess formed in its lower surface, an internal filler member fitted into the interior recess of said external member for reflected light passing through said external member and being in surface contact with said external member within the recess, said filler member having a bottom surface arranged to be supported on the roadway surface, a lightrefracting surface on the exterior upper surface of said external member for refracting light inwardly through said external member to said filler member, said light-refracting surface forming an acute angle with the plane of the bottom surface of said filler member, said filler member composed on a base section including the bottom surface of said filler member and a rectangularly shaped upper section extending upwardly from the said base section, said base section extending laterally outwardly from said upper section at least along one side thereof, the upwardly facing surface of said base section extending laterally outwardly from said upper section forming a single continuous planar first light reflecting surface disposed in spaced and generally parallel relationship with the bottom surface of said filler member, said first light refleeting surface being arranged in opposed spaced relationship with said light refracting surface, a zig-zag refleeting surface formed on the side of said upper section of said filler member extending upwardly from said first light reflecting surface at a location spaced inwardly from the outer peripheral edge of said first reflecting surface and being contact with said external member within the recesss therein, said zig-zag surface being composed of a multiplicity of continuous upwardly extending surfaces arranged in side by side relationship, each of surfaces being disposed normally to the adjacent surfaces and being arranged in pairs of facing surfaces forming a continuous line of V-shaped recesses in said zig- References Cited UNITED STATES PATENTS 2,153,634 4/1939 Magarian 350-103 X 3,409,344 11/1968 Balint et al. 350-103 2,328,407 8/1943 Becker 350--97 X 1,791,936 2/1931 Rolph 350-103 2,818,500 12/1957 Franck 350--103 X 3,057,256 10/ 1962 Erban 350-103 3,332,327 7/1967 Heenan 350-103 X PAUL R. GILLIAM, Primary Examiner U.S. Cl. X.R. 94-l.5; 350--103