DE9000395U1 - Headlights for motor vehicles - Google Patents

Description

· I I

R. 23157 11.1.1990 Gu/Ec

ROBERT BOSCH GMBH, 7000 STUTTGART 10

Headlights for motor vehicles Stand de- Techsi>

The invention relates to a headlight for motor vehicles according to the type of claim 1.

Such a headlight is known from DE-OS 36 02 262. This headlight has a reflector which, together with a lens, forms an optically effective edge of a diaphragm as a light-dark boundary. The lens is divided into several aspherical segments on the side facing away from the reflector. The segments are offset from one another in the direction of the optical axis, with the offset steps between the segments being rounded. However, this headlight cannot meet legal requirements for dipped headlights or fog lights, according to which certain minimum light values must be present in defined areas above the light-dark boundary.

Advantages of the invention

The headlight according to the invention with the characterizing features of claim 1 has the advantage that part of the light is directed through the cylindrical lens into a certain angular range n.-h

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is deflected upwards and the light values above the cut-off line are increased, so that the legal requirements are met, especially for fog lights. Due to the arrangement of the '''linder lens on the lens or the lens, no additional component is required.

Advantageous embodiments of the headlight are characterized in the subclaims. The arrangement of the cylindrical lens according to claim 2 allows it to be manufactured with little effort. The embodiment according to claim 3 or 4 avoids undesirable interference effects.

drawing

Two embodiments of the invention are shown in the drawing and explained in more detail in the following description. Figure 1 shows a headlight in a simplified, perspective view, Figure 2 shows a part of the lens as a first embodiment, Figure 3 shows a part of the lens of the headlight from Figure 1 as a second embodiment in vertical section and Figure 4 shows a coordinate system with a predetermined zone A.

Description of the embodiments

A headlight for motor vehicles, which is in particular a lever headlight, has a reflector 10 and a light source 12 arranged on the optical axis 11 of the reflector 10. The rays generated by the light source 12 form a light beam by reflection on the reflector 10, in which a diaphragm 13, a lens 14 and a lens 16 are arranged. The lens 14 is made of pressed glass and projects the optically effective edge 17 of the diaphragm 11 as the light-thickness boundary of the light beam onto the road. The side of the light source facing away from the reflector 10 is

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To suppress the color saturation at the outer edge 17 of the objective lens 14, it is divided in a horizontal plane IfI into an upper aspherical segment 19 and a lower aspherical segment 70. The inner segment 20 is set back relative to the upper segment 19 in the direction of the optical axis 11 toward the reflector If).

In a first embodiment, shown in Figure 2,

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Part of a horizontally arranged convex cylindrical lens 21, through which the partial light beam striking it is deflected upwards in a fixed angular range, as shown in beam 22.

The transition from the cylindrical lens 21 to the upper segment 19 is continuous, that is, the cylindrical lens and segment have the same tangents T at their point of contact.

The angular range in which the light is deflected upwards is determined by zone A defined in Figure 4. Zone A is defined in ECE Regulation No. 19 in terms of its position with respect to a given coordinate system, according to which it extends from -5.14° to +5.14° on the horizontal axis H and from 0° to +1.72° on the vertical axis V. ECE Regulation No. 19 requires minimum light values in zone A of 0.15 to 1 lux. These minimum light values are achieved by the targeted deflection of a partial light beam by the cylindrical lens 21 into zone A.

In a second embodiment shown in Figure 3, the lens 14 is not segmented. A sector of a horizontally arranged concave cylindrical lens 23 is formed on the side of the lens 16 facing the lens, the part of the cylindrical lens 23 being so wide that the partial light beam striking it, as shown by beam 24, is directed into zone A according to

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is deflected upwards. The sector of the cylindrical lens 23 is designed in such a way that it has an upper horizontal boundary surface 25 and an inner uppermost edge, which is visible in Figure 3 as point Pl, since this runs perpendicular to the plane of the drawing. The boundary surface 25 intersects the light disk 16 in a line, which is also only visible in Figure 3 as point P2. The vertical tangent Tl applied to the edge of Pl runs parallel to the tangent Tl applied to the edge of Pl. Î *t Î ...

Several cylindrical lenses can also be arranged vertically one above the other on the lens.

The partial light beam deflected upwards by the 2" ¹ or 23 cylindrical lens enables the legally required light values for fog lights to be met above the cut-off line.

Claims (4)

R. 231r>7 11.1.1990 Gu/Ec ROBERT BOSCH GMBH, 7000 STUTTGART 10 Claims 1. Headlights for motor vehicles, in particular fog lights, with a reflector (10) which generates a light beam by reflecting the rays of a light source (12), in the beam gong of which a diaphragm (13) with an optically effective edge (17) is arranged, with a lens (14) which images the edge (17) as a light-dark boundary of the light beam on the roadway, with a light disk (16) and with optical means in the form of cylindrical lenses (21, 23) for influencing the light distribution of the light beam, characterized in that at least some of the cylindrical lenses (21, 23) are arranged horizontally on the lens (14) or the light disk (16), by means of which a part (22, 24) of the light beam is deflected upwards into a fixed angular range. 2. Headlight according to claim 1, characterized in that the lens (14) is divided into several segments (19, 20) lying one above the other, with a lower segment (20) being set back relative to an upper segment (19) in the direction of the optical axis (11) towards the reflector (10) and the cylindrical lens (21) being formed at the transition between the lower and upper segments. 3. Headlight according to claim 2, characterized in that the transition between the cylindrical lens (21) and the upper segment (19) is stepless. - 2 - R. Z 3.l'j V 4. Headlight according to claim 1, characterized in that the cylindrical lens (2\) is arranged on the side of the lens (16) facing the objective (14) and is designed as a half-line projecting inwards in a step-like manner, with a horizontal upper boundary surface (25) whose vertical tangent (T1) applied to the uppermost inner edge runs parallel to the vertical tangent (T2) to the lens (16) on a line defined by the intersection of the upper boundary surface (25) with the lens (16).