MXPA98008629A - Warning lamp with diode emitters of light, directional of destel - Google Patents

Abstract

A warning lamp with directional flashing light emitting diodes having a housing, a printed circuit board secured within the housing, a plurality of light emitting diodes mounted on the printed circuit board and operatively arranged to produce light, which is directs away from the housing and directed directionally to project a beam over a minimum area from about 20§a right to 20§a left in a horizontal plane and from 10§ upward to 10§ downward in a vertical plane, and a circuit controller operatively arranged to flash the plurality of emitting diodes of the

Description

WARNING LAMP WITH LIGHT EMITTING DIODES, DIRECTIONAL OF DESTELLEO Field of the Invention The present invention relates generally to warning lamps with directional flashing, more particularly to a directional lamp with light emitting diodes (LED = Light Emiting Diodes) and even more particularly to a LED directional lamp that meets the standards of the Society of Automotive Engineers (SAE = Society of Automotive Engineering). BACKGROUND OF THE INVENTION The Society of Automotive Engineers (SAE) publishes many new standards revised and reaffirmed each year, in three categories, including ground vehicle standards (J reports). Information regarding these standards is available on the World Wide Web at HTTP: // www. fae. org. Two of these SAE standards are relevant to this invention. J 595 provides design guidelines, references to test procedures, and performance requirements for flashing incandescent warning lamps. It is intended to apply, but not limited to, land surface vehicles. The purpose of the standard is to establish general requirements for flashing warning lamps for use in authorized emergency, maintenance and service vehicles. This standard applies only to incandescent warning lamps, supposedly because to date only incandescent lamps can comply with this standard. A flashing warning lamp is defined by the standard as a lamp, where a light source is turned on and off by circuit interruption that produces a repetitive flash of light that is directed directionally and projects a beam signal with flash over a minimum area of 20 ° to the right to 20 ° to the left in a horizontal plane and from 10 ° up to 10 ° down in a vertical plane. Next, two photometric requirements of a warning lamp are re-printed, as set out in Tables 1 and 2, respectively, of J 595: NORM SAE J 595 TABLE 1- PHOTOMETRIC DESIGN GUIDES Luminous Intensity Points,, Candelas Tests Degrees White Yellow Roi or 5L 80 40 20 10U-V 200 100 50 5R 80 40 20 20L 80 40 20 10L 200 100 50 NORMA SAE J 595 (Continued) TABLE 1-PHOTOMETRIC DESIGN GUIDES Luminous Intensity Points,, Candelas Testing Grades White Yellow Roio 5L 400 200 100 SU-V 600 300 150 5R 400 200 100 10R 200 100 50 20R 80 40 20 20L 120 60 30 10L 300 150 75 5L 800 400 200 H-V 1200 600 300 5R 800 400 200 10R 300 150 75 20R 120 60 30 20L 80 40 20 10L 200 100 50 5L 400 200 100 5D-V 600 300 150 5R 400 200 100 10R 200 100 50 20R 80 40 20 20L 80 40 20 NORMA SAE J 595 (Cont.) TABLE 1-PHOTOMETRIC DESIGN GUIDES Luminous Intensity Points, Candelas Tests Grades White Yellow Roio 10L 200 100 50 5L 400 200 100 5D-V 600 300 150 5R 400 200 100 10R 200 100 50 20R 80 40 20 5L 80 40 20 10D-V 200 100 50 5R 80 40 20 TABLE 2 • - PHOTOMETRIC REQUIREMENTS Puni: Luminous Intensity, Candelas Prucsbae White Zone Yellow Zone Red Zone Areas Total Total Total Degrees 5U- • 10L 5U- • 20L 1 H-20L 600 300 150 5D- • 20L 5D- 10L 10U-5L 2 10U-V 320 160 80 TABLE 2 - PHOTOMETRIC REQUIREMENTS (Cont.) Luminous Intensity Points, Candelas Tests White Zone Yellow Zone Red Zone Zones Grades Total Total Total 10U-5R 5U-5L H-10L 1000 500 250 5D-5L 5U-V H- • 5L H- • V 3600 1800 900 H- 5R 5D-V 5U-R H-10R 1000 500 250 5D-5R 10D-5L 10D-V 320 160 80 10D-5R 5U-10R 5U-20R H-20R 600 300 150 The SAE J 1318 standard also applies to directional warning lamps. The standard defines a directional warning lamp as a lamp that produces a repetitive flash of light that is directed directionally and projects a flashing signal over a minimum area of to the right to 20 to the left, in a horizontal plane and from 10 ° up to 10 ° down in a vertical plane. The photometric requirements of a directional warning lamp are then reprinted as set out in Tables 4 and 8 respectively of J 1318: SAFETY STANDARD J 1318 TABLE 4 PHOTOMETRIC REQUIREMENTS CLASS 1 DIRECTIONAL GASEOUS DISCHARGE WARNING LAMPS Minimum Flashing Energy Requirements Zone Totals (candela-seconds) Zone Energy flash-candela-sec Point White Yellow Red signal blue test degrees 5U-10L 5U-20L # 1 H-20L 108 54 27 * NORMA SAE J 1318 (Continued) TABLE 4 Minimum total flash energy requirements Zone (candela-seconds) Zone Energy flash-candela-sec Point White Yellow Red blue test signal grades 5D-10L 10U-5L # 2 10U-V 56 28 13 * 10U- 5R 5U-5L # 3 H-10L 184 92 46 * 5D-5L 5U-V H-SL # 4 HV 664 332 116 H-5R 5D-V 5U-R # 5 H-10R 184 92 46 5D-5R 10D- 5L # 6 10D-V 56 28 14 SAE J 1318 STANDARD (Cont.) TABLE 4 Minimal Flashing Energy Requirements Zone Totals (candela-seconds) Flashing Energy Zone-candela-sec Spot White Yellow Red signal proof blue degrees 10D-5R 5U-10R SU-20R # 7 H-20R 108 54 27 * 5D-20R 5D-10R TABLE 8 PHOTOMETRIC DESIGN GUIDES GASEOUS, DIRECTIONAL DISCHARGE WARNING LAMPS Minimal Design Flash Energy Guides Warning Lamps Flash Energy-candela-sec White Yellow Point Red Blue Test Signal Grade 10U-5L 12 6 3 * 10U-V 32 16 8 * TABLE 8 (Cont.) PHOTOMETRIC DESIGN GUIDES GASEOUS, DIRECTIONAL DISCHARGE WARNING LAMPS Minimal Design Flash Energy Guides Warning Lamps Flash Energy-Candela-Sec White Yellow Point Red Blue Test Signal Grades 10U-5R 12 6 3 5U-20L 12 6 3 5U-10L 32 16 8 5U-5L 68 34 17 5U-V 100 50 25 5U-5R 68 34 17 5U-10R 32 16 8 5U-20R 12 6 3 H-20L 20 10 5 H-10L 48 24 12 H-5L 132 66 33 HV 200 100 50 H-5R 132 66 33 H-10R 48 24 12 H-20R 20 10 5 5D-20L 12 6 3 TABLE 8 (Cont'd) PHOTOMETRIC DESIGN GUIDES GASEOUS, DIRECTIONAL DISCHARGE WARNING LIGHTS Minimal design flash energy guides Warning lamps Power flashing- candela-sec Point of White Yellow Red signal proof blue degrees 53-10L 32 16 8 * 5D-5L 68 34 17 * 5D-V 100 50 25 * 5D-5R 68 34 17 * 5D-10R 32 16 8 * 5D -20R 12 6 3 * 10D-5L 12 6 3 * 10D-V 32 16 8 * 10D-5R 12 6 3 * Both standards J 595 and J 1318 are incorporated herein by reference. To date, only incandescent lamps have been manufactured to comply with J 595 and only the beam and incandescent discharge lamps have been manufactured to comply with the J 1318 standard. What is required then is a lamp structure comprising LEDs that meet the requirements of SAE J 595 and J 1318. COMPENDIUM OF THE INVENTION The invention broadly comprises a directional flashing warning light with light-emitting diodes, having a housing, a printed circuit board secured within the housing, a plurality of light-emitting diodes mounted on the printed circuit board and operatively arranged to produce light that is directed away from the housing and directionally oriented to project a beam over a minimum area of about 20 ° to the right to 20 ° to the left in a horizontal plane and 10 ° upwards to 10 ° downwards in a vertical plane, and a controller circuit operatively arranged for to flash the plurality of light emitting diodes. The main objective of this invention is to provide a directional flash warning light with light-emitting diodes that complies with the J 595 and J 1318 standards of the Society of Automotive Engineers. Another object of the invention is to provide a directional warning lamp that is more efficient to operate and less susceptible to vibration than conventional beam and incandescent discharge lamps.

These and other characteristic objects and advantages of the invention will be more readily apparent from the following detailed description of the drawings and the claims. BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a perspective view of a service truck having flash directional warning lamps fixed to the rear thereof; Figure 2a is a side view of one of the lamps shown in Figure 1 in a view intended to illustrate one of the photometric requirements of the lamp; Figure 2b is a top view of one of the lamps shown in Figure 1, in a view intended to illustrate another of the photometric requirements of the lamp; Figure 3 is a perspective view of the directional warning lamp of the invention; Figure 4 is a cross-sectional view of the lamp shown in Figure 3, which is generally taken on line 4-4 of Figure 3; Figure 5 is an exploded view of the warning lamp shown in Figure 3; Figure 6 is a perspective view of the light direction element of the invention; and Figure 7 is an electrical schematic diagram of the controller circuit of the invention. DETAILED DESCRIPTION OF THE PREFERRED MODE At the outset, it should be understood that this invention comprises a directional flashing light emitting diode warning lamp that complies with selected SAE standards. Although a particular preferred embodiment of the invention is described herein, it will readily be apparent that various other alternate embodiments can be achieved without departing from the scope or spirit of the invention. Similar reference numerals refer to identical structural elements in the various drawings. Figure 1 is a perspective view of a service truck 10 having 4 directional warning lamps with light emitting diodes that flash 20 fixed at their rear. The lamps can be mounted on any vehicle and are not necessarily limited to trucks. To comply with the SAE standards, the lamp 20 must project a beam of flashing light over a minimum area from 20 ° to the right, 20 ° to the left in a horizontal plane and 10 ° up to 10 ° down in a vertical plane. Figure 2a is a side view of one of the lamps 20 shown in Figure 1, illustrating the requirement of the beam by looking up / looking down. Figure 2b is a top view of one of the lamps 20 illustrated in Figure 1, showing the beam requirement 20 ° to the left / 20 ° to the right. The minimum SAE flash energy requirements of J 1318, as measured at a distance "D" equal to at least 18 meters away from the lamp, and the light intensity requirements of J 595, are measured at a distance "D" "Equal to at least 3 meters. The lamp 20 is illustrated in perspective view in Figure 3. The lamp broadly comprises a housing 21 and fixed lens 22. The components of the lamp are illustrated in cross-sectional bits in Figure 4, which is a view that is generally taken on line 4-4 of Figure 3. The components are also illustrated in exploded view in Figure 5. Now noting Figures 3, 4 and 5, the housing 21 is preferably round and made of plastic, although other shapes and compositions are certainly possible. The circuit board 26 is mounted to the floor of the housing and contains several circuit components of the controller circuit illustrated in Figure 7 (although many of the components of the controller circuit are preferably located on a circuit board that is remote from the housing). The plurality of light-emitting diodes (LEDs) 24 is mounted on the circuit board 23. High-output LEDs should be used for the warning lamp.

In a preferred embodiment, LEDs part number HPWT-DH 00 (red) manufactured by Hewlett Packard were employed. Others Hewlett Packard LEDs are Nos. HPWT-DHOO models (amber), HLMP-DL08 (amber), HLMP-DH08 (red), HLMT-DH08 (red), and HLMT-DL08 (amber); although LEDs from other manufacturers may also be convenient. To comply with the SAE standard, a minimum number of LEDs must be operational on each board. Although the exact number can vary, depending on the model of LED used, the light output of each LED, the color LED and the lenses used and other factors, it has been found that an amount of sixty (60) LEDs HPWT-DLOO complies with the SAE photometric requirements. Since the LEDs generate a certain amount of heat, it is preferable that a collector or heat sink was used to dissipate this heat. The thermal collector 38, preferably made of aluminum, is thermally connected to the printed circuit board, but electrically isolated therefrom by the heat conducting electrical insulator 41. The heat is transported away from the collector by fins 39.

The light directing element 32 contains a plurality of reflective compartments / light directors, with each compartment arranged to direct the light emitted from a particular LED. The element 32 can be constructed of a reflective material, such as aluminum, or it can be made into a non-reflective substrate such as plastic and then coated with a reflective material. The element 32 is illustrated in an enlarged perspective view in Fig. 6. The compartments 34 to 37 are frustoconical in shape, with a smaller opening at one end of each compartment intended to fit firmly on each LED. Each compartment is widened in diameter away from the LED, to reflect and direct LED decade light in a beam of substantially conical shape. Four of these bundles formed by the compartments 34 and 37 are illustrated in Figure 6. The lens 22 is placed on the light reflecting / steering element 32. The lens may be transparent or translucent. It can be clear in red, amber or other color. It can be made of plastic, glass or any other convenient material that goes to light. In a preferred embodiment, the lens is made of plastic. The thermal collector 38, the circuit board 23, light reflecting / steering element 32 and the lens 22 are held together by mounting screws 33a-32d, which pass through holes in the elements 38, 23 and 32 and are receive in the receivers threaded in the lens 22. It is preferable that the lamp structure is resistant to vibration and moisture. For this purpose and noting Figure 4, an epoxy 40 is emptied onto the circuit board 23 and allowed to flow around the LED housings (at a lower height than the LEDs themselves). When the epoxy is set, the LEDs lock firmly in place on the circuit board and are extremely resistant to vibration and moisture. The plurality of LEDs is caused to flash by the controller circuit illustrated in Figure 7. The circuit comprises a regulator circuit that supplies power to an oscillator circuit and a pair of monostable oscillators (oneshot) that displace the LED structure. The output of each raonostable is connected to a gate O (OR) the output of which is connected to a transistor switch that controls the illumination of the LED lamps. In operation, the oscillator produces an "on" pulse of relatively short duration, followed by a relatively long "disconnected" duration. This signal is applied simultaneously to each monostable. However, the first monostable is configured to fire the edge that is positive to the pulse and the second is configured to trigger the edge that goes to the negative pulse. The synchronization of each monostable is set to some duration shorter than that of the on time of the oscillator; in this way, the two monostable produce pulses of short duration in sequence followed by a relatively long period of rest. The output is combined in gate O (OR) and applied to the transistor switch thus producing flashes of light from the LED lamp corresponding to the output of gate O (OR). The result is two flashes of light of short duration followed by a relatively long period of rest, followed by two flashes of short duration and so on. The circuits can be circumscribed within a lamp unit and fed to other lamps in a "master, slave" configuration or they can be located outside the lamp unit in a separate encapsulated module. The circuit consists of integrated circuits Ul (a voltage regulator LM 7812 with three fixed positive terminals), U2 (a synchronizer NE 555) U3 (a dual monostable multivibrator 4098 CMOS); diodes D3 and D4 (which form a diode or gate); and Ul transistor (a Power MOSFET of channel N).

The voltage regulator circuit, consisting of capacitors Cl, C2, and LM 7812, maintains the voltage at 12 volts constant for circuit operation. The NE 555 synchronizer is configured in a typical way as a pulse generator with diodes DI and D2, capacitor C4 and resistors Rl and R2 selected to produce an approximate pulse width of 140 milliseconds, and a recurrent pulse time of approximately 1.3 seconds . The synchronization components of both halves of the monostable 4098 (C5 and R3 and C6 and R4) are chosen to produce an approximate pulse width of 80 milliseconds. The output of terminal 3 of NE 555 (U2) applies to both halves of the 4098 simultaneously, however, the signal applied to the positive trigger supply (terminal 4 of U3A) DI and the negative trigger supply of the other (terminal Ull of U3V). The result is that there is a pulse of 80 msec, produced in terminal 6 of the U3A, when the transition going positive from the output pulse of U2 and another produced in terminal 10 of the U3B when the transition going to negative of the U2 exit. The outputs of terminals 6 and 10 are combined in an "O" diode gate formed by diodes D3 and D4. The result is a pair of pulses of duration 80 msec separated by approximately 60 msec of recurrent disconnection time each .3 second. The output of gate "O" is applied to the transistor that is used to switch the ground to an LED lamp or plurality of LED lamps 15, to produce a double strobe flash that "attracts attention" separated by approximately 1.2 seconds of time Disconnect and then repeat whenever the power is applied. It will be appreciated that the controller circuit shown in FIG. 7 is no more than an example of a convenient LED driver circuit. Programmable circuits, as well as other control circuits are readily known in the art. Although our invention is described by reference to preferred specific embodiments, it is clear that variations may be practiced without departing from the spirit of the invention as claimed.

Claims (18)

1. CLAIMS 1.- A directional warning lamp with flashing light-emitting diodes, characterized in that it comprises: a housing; a lens attached to the housing; a printed circuit board attached inside the housing; a plurality of light emitting diodes mounted on the printed circuit board and operatively arranged to produce light that is directed away from the housing and directionally oriented to project a beam through the lens over a minimum area of about 20 ° to the right to 20 ° to the left in a horizontal plane and 10 ° up and 10 ° down in a vertical plane; and a driver circuit operatively arranged to flash the plurality of light emitting diodes; where the warning lamp meets the minimum photometric requirements of the J 595 and J 1318 standards of the Society of Automotive Engineers.
2. 2. A warning lamp according to claim 1, characterized in that the lens is transparent.
3. 3. - A warning lamp according to claim 1, characterized in that the lens is translucent.
4. 4. - A warning lamp according to claim 1, characterized in that the lens is light colored.
5. 5. - A warning lamp according to claim 1, characterized in that the lens is red.
6. 6. - A warning lamp according to claim 1, characterized in that the lens is amber.
7. 7. A warning lamp according to claim 1, characterized in that the lens is colored blue signal.
8. 8. - A directional warning lamp with flashing light-emitting diodes, according to claim 1, characterized in that the lamp produces white light having a minimum luminous intensity of 80 candelas measured at a distance of at least 3 meters away from the lamp. lamp.
9. 9.- A directional warning lamp with light emitting diodes flashing, according to claim 1, characterized in that the lamp produces yellow light having a minimum luminous intensity of 40 candles measured at a distance of at least 3 meters away from the lamp. lamp.
10. 10. - A directional warning lamp with light emitting diodes flashing, according to claim 1, characterized in that the lamp produces red light having a minimum luminous intensity of 20 candelas measured at a distance of at least 3 meters away from the lamp.
11. 11. A directional warning lamp with flashing light emitting diodes, according to claim 1, characterized in that the lamp produces blue signal light.
12. 12. - A directional warning lamp with flashes of light-emitting diodes, according to claim 1, characterized in that it has a minimum flashing energy in the range of 2 to 48 candelas-seconds measured a distance of at least 18 meters away of the lamp .
13. 13. - A directional warning lamp with flashing light-emitting diodes, according to claim 1, characterized in that the lamp produces yellow light that has a minimum flash energy in the range of 1 to 22.5 candela-seconds measured at a distance of at least 18 meters away from the lamp.
14. 14. A directional warning lamp with flashing light emitting diodes, according to claim 1, characterized in that the lamp produces red light having a minimum flash energy in the range of .5 to 11 candela-seconds measured to a distance of at least 18 meters away from the lamp.
15. 15. A directional warning lamp with flashes of light-emitting diodes, according to claim 1, characterized in that the lamp produces light blue signal having a minimum flash energy in the range of .25 to 11 candela-seconds measure a distance of at least 18 meters away from the lamp.
16. 16.- A directional warning lamp with flashing light-emitting diodes, according to claim 1, characterized in that it also comprises a light reflecting / steering element attached to the printed circuit board and operatively arranged to project a light beam through the lens of each light emitting diode.
17. 17. A directional warning lamp with flashes of light-emitting diodes, according to claim 1, characterized in that the light-emitting diodes are attached to the printed circuit board by both soldered and epoxy terminals.
18. 18. - A directional warning lamp with flashing light-emitting diodes, according to claim 1, characterized in that the driver circuit causes the plurality of light-emitting diodes to flash at a speed of 0.8 to 2.2 Hz.