Abstract:
An electroluminescent illuminated gauge which can be used by technicians in all conditions of weather and situations involving poor visibility due to lighting is disclosed. The electroluminescent illuminated gauge is very useful to illuminate a gauge, in which the dial is non-illuminating. The front side of the portable electroluminescent illuminated gauge is illuminated. The front side of the dial lamp may be fixed on the front side of a gauge using a double sided adhesive, which facilitates the technicians to have free hands to perform any necessary work, without holding a torch with one hand.

Description:
TECHNICAL FIELD  
       [0001]     The present invention pertains generally to methods and devices pertaining to lamps and more particularly to methods and devices pertaining to electroluminescent illuminated gauges to illuminate gauges, more particularly in situations involving poor visibility due to lighting or weather conditions.  
       BACKGROUND  
       [0002]     Technicians working in the maintenance departments of industries have to work in all conditions of weather and situations involving poor visibility due to lighting. They have to record the readings in gauges such as pressure gauges. Most gauges currently come with some type of reflective dial. These are somewhat easily seen during daylight hours or when illuminated with a light at night or during diminished light conditions. However, many of these gauges are located on devices in the field, where a technician would have to find some way to illuminate the gauge during night time or under diminished light conditions in order to check a pressure, like that of a Freon in an automobile, a sprayer attached to a tractor spreading chemicals onto a field, a utility worker checking pressure on a gas line connected to a home, a gauge fixed on a medical device, or a gauge fixed on a piece of farm equipment. 
     
    
     DESCRIPTION OF DRAWINGS  
       [0003]      FIG. 1  shows a plan view of an electroluminescent illuminated gauge according to an example embodiment of the inventive subject matter.  
         [0004]      FIG. 2A  shows a front perspective view of the electroluminescent illuminated gauge shown in  FIG. 1  according to an example embodiment of the inventive subject matter.  
         [0005]      FIG. 2B  shows a partial cross-sectional view taken along the line  2 B of  FIG. 2A .  
         [0006]      FIG. 3A  shows a front view of a gauge lamp;  
         [0007]      FIG. 3B  shows a back view of a gauge lamp including connections to a source of power;  
         [0008]      FIG. 4  illustrates a side view of an embodiment of an EL gauge lamp including an adhesive layer;  
         [0009]      FIG. 5  shows a view of a pair of electroluminescent illuminated gauges.  
         [0010]      FIG. 6  illustrates a two gauge valve according to one example embodiment of the inventive subject matter. 
     
    
     DETAILED DESCRIPTION  
       [0011]     In the following detailed description of the inventive subject matter, reference is made to the accompanying drawings which form a part hereof, and in which is shown, by way of illustration, specific embodiments in which the inventive subject matter may be practiced. In the drawings, like numerals describe substantially similar components throughout the several views. These embodiments are described in sufficient detail to enable those skilled in the art to practice the inventive subject matter. Other embodiments may be utilized and structural, logical, and electrical changes may be made without departing from the scope of the present invention.  
         [0012]     Referring now to  FIGS. 1, 2A  and B,  3 A,  3 B and  4 , there are illustrated various views of an electroluminescent (EL) illuminated gauge  100 , according to an example embodiment of the inventive subject matter. Gauge  100 , in one example embodiment, is a pressure gauge, and includes a housing  102  and a gauge display assembly  104 . Gauge display assembly  104  includes a gauge face  106  including measurement scale indicia  108 , a gauge indicator  110 , and optionally a transparent gauge lens or cover  112 . Indicator  110  is driven by the measurement mechanism (not shown), which receives an input  105 , such as the pressure of a liquid or gas, and activates or controls the indicator  110  in response thereto to provide a desired gauge function.  
         [0013]     Attached to transparent cover  112  is an EL gauge lamp unit  120 . Gauge lamp unit  120  includes an EL lamp  125  having a surface area  127  (highlighted in  FIG. 3A  with hash marks) that glows with EL light, when activated, on the front side  122  of lamp  125 . Side  122  is attached to transparent cover  112 , for example with a transparent adhesive  123  (see  FIG. 4 ), so that the illumination from the side  122  glows down through the transparent cover  112  onto the gauge face  106 . Accordingly, the face  106  of the gauge is illuminated. According to one example embodiment, where the gauge face  106  is circular in shape, the side  122  is also generally circular or oval in shape, and is sized such that it can be applied to the cover  112  so that its center aligns with the center of the circular gauge face and so that it is of a diameter that does not substantially interfere with the reading of the gauge indicia  108 . According to one example embodiment, gauge lamp unit is substantially flat or planar, and is made of flexible material so that it can flex to conform to any surface it is attached to. Such flexible material may include a flexible printed circuit substrate.  
         [0014]     In one example embodiment, the gauge lamp unit  102  may overlay or cover some portion of the gauge indicia  108  within an area  109  closest to the center of the dial, but not the indicia  108  on the outer area  111  of the face of the gauge. Still further, according to one example embodiment, gauge lamp unit  120  may include a stem  121  that extends from the main body of the unit  120 . Leads  146  (for example but not by way of limitation six to eight inches long) connect to, as shown in  FIG. 3B , electrodes on the EL lamp unit  120 , which in turn may be connected to an electrical pack  130  including electronics and power for activation the EL lamps, such as an inverter and a rechargeable or non-rechargeable battery. Electrical pack  130  further includes a switch control  132  that can be used to switch power on and off to the EL lamp  125 . According to one embodiment, the switch  132  may be a push button switch that includes a timer and such that the switch automatically turns off after a pre-set delay period. According to another embodiment, the switch  132  may be activated by a proximity sensor that detects the proximity of an object, such as a user. According to another example embodiment, switch  132  then automatically activates the gauge for a predetermined delay period, and then shuts off automatically.  
         [0015]     According to another example embodiment, as shown in  FIG. 4 , the front surface  122  of the EL lamp  125  is covered with a double-sided adhesive  123  with a peel-off cover  131 . According to one example method, the lamp unit  120  is applied to a gauge  100  by peeling off cover  131  from the adhesive  123  and pressing the EL lamp  125  onto the transparent cover  112  of the gauge  100 .  
         [0016]     Referring now more specifically to  FIG. 3A  and  FIG. 3B , there is illustrated the construction of an EL gauge lamp unit  120  according to one example embodiment of the inventive subject matter, wherein  FIG. 3A  illustrates the front, glowing side of lamp unit  120 , and  FIG. 3B  illustrates the back of EL gauge lamp unit  120 . According to one example embodiment, the EL lamp uses high bright blue phospher, to provide a blue tinted lighting for the gauge. EL gauge lamp unit  120  has a round end  140  and a narrower rectangular stem  121  end, and, in one embodiment, the lamp surface area  127  extends across substantially the entire area of the lamp unit  120 , including both ends  140  and the stem end  121 , and in-between the ends. In one embodiment, electrical power is supplied to the EL lamp electrodes  144  accessible at the center of the round end  140 . Wire leads  146  run down the stem  121  and, in one example embodiment, are cured to the lamp unit  120  with a UV cured adhesive. Leads  146  are crimped to the respective electrodes  144  to supply power to the lamp unit  120 . As illustrated in  FIG. 5 , one or more lamp units  120  may be connected by leads  146  to a power pack unit  130 , which in one embodiment may include an inverter and a battery, such as a size 2450 battery. A dual lamp unit  500  such as shown in  FIG. 5  may be used to illuminate a two-face gauge  600  such as shown in  FIG. 6 . In one embodiment, a lamp unit  120  end  140  may have a diameter of about 0.75 inches or equivalent metric size, and the stem may be about 1 inch long and 0.375 inches wide or equivalent metric size.  
         [0017]     Although in one example embodiment, the EL light provided by a lamp unit  120  may be blue tinted, any other color light may be used. In one example embodiment, a soft tinted light may be preferred. In another embodiment, the indicia  108  on a gauge may be phosphorescent or another chemical composition that may glow under EL lighting conditions to enhance the visibility of the gauge face even more.  
         [0018]     Although specific embodiments have been illustrated and described herein, it will be appreciated by those of ordinary skill in the art that any arrangement which is calculated to achieve the same purpose may be substituted for the specific embodiment shown. This application is intended to cover any adaptations or variations of the present invention. It is to be understood that the above description is intended to be illustrative, and not restrictive. Combinations of the above embodiments and other embodiments will be apparent to those of skill in the art upon reviewing the above description. The scope of the inventive subject matter includes any other applications in which the above structures and fabrication methods are used. The scope of the inventive subject matter should be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled.