Illuminant display device and motor license plate using same

• US 4,255,887 A
• Filed: 04/23/1979
• Issued: 03/17/1981
• Est. Priority Date: 07/28/1978
• Status: Expired due to Term

• Current Assignee: Nihon Number Plate Kabushiki Kaisha
• Original Assignee: Nihon Number Plate Kabushiki Kaisha
• Inventors: Murai, Tetsunosuke
• Primary Examiner(s): Pitrelli, John F.
• Application Number:
  US06/032,682
• Time in Patent Office: 694 Days
• Field of Search: 40/204, 40/205, 40/206, 340/99, 315/360
• US Class Current: 40/206
• CPC Class Codes: B60Q 1/56 for illuminating registrations or the like , e.g. for licence plates

Abstract

The disclosed illuminant display device is to be used on a motor vehicle for publicity or other purposes. In the device an opaque plate member contains perforations in the shape of a character or figure to be displayed, and tinted translucent pieces are set in the perforations transmit light which is projected from a light source provided behind the perforated plate. The display device can serve as an illuminant license plate which is arranged to illuminate the identifying characters continuously for a predetermined time period after the headlight or parking light of the motor vehicle has been turned off and thereby foil a driver who tries to conceal the identity of the vehicle by turning off the lights for hit-and-run or other unlawful purposes.

Claims

1. For a vehicle with a power supply circuit, headlamps, parking lamps and a switch for connecting the headlamps and parking lamps to the power supply circuit, an illuminant license plate device comprising:

a license plate of an opaque material having perforations in the shape of identifying characters;

a light source located inward of said license plate for projecting light toward said translucent pieces;

switch means in the power supply circuit for energizing the light source;

a delay circuit in the power supply circuit to maintain the switch means to the light source in a closed state for a predetermined time period after said headlight or parking light has been turned off; and

a light distributor plate interposed between said light source and said license plate and having a transparent masking sheet adhered to a position opposite said light source, said masking sheet having a density increasing in degree from peripheral portions toward the center thereof to distribute the light uniformly from said light source before transmission through said translucent pieces in said license plate;

said delay circuit including a capacitor and a resistor in parallel with each other;

said delay circuit further including a switching element operable in relation to the terminal voltage of said capacitor to control opening and closing of said power supply circuit of said light source;

said translucent pieces being heat pressed to the license plate at the perforations for securing the pieces in the plate.

2. A device as in claims 1, wherein the colors of said translucent pieces in one plate are different from the colors of the pieces in the other plate section.

3. A device as in claims 1, wherein a plurality of said translucent pieces represent alphanumeric characters, each of the characters represented being continuous and complete, said perforations receiving alphanumerically shaped pieces being cut to allow passage of light through the entire extent of the alphanumeric character of the piece.

4. A device as in claims 1, wherein the colors of said translucent piece in one plate are different from the colors of the pieces in the other plate section, and wherein a plurality of said translucent pieces represent alphanumeric characters, each of the characters represented being continuous and complete, said perforations receiving alphanumerically shaped pieces being cut to allow passage of light through the entire extent of the alphanumeric character of the piece.