Abstract:
A combination battery, light bulb, fuse tester having novel features. In particular, the tester includes a novel probe apparatus comprising an actuator, a pair of opposed probe arms, each of the probe arms having an electrical contact on an end thereof, the probe arms being adapted such that operation of the actuator biases the ends of the probe arms away from each other to an open position allowing the electrical poles of a battery, light bulb, or fuse to be tested to be contacted by the contacts on the probe arms. Additional features include magnetic probe contacts to facilitate the testing of a battery, light bulb, or fuse.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    The present invention relates to a device and method for testing batteries, light bulbs, and fuses. More specifically, the invention relates to a device and method for testing batteries, light bulbs and fuses which provides accurate, easy-to-read results as to the condition of the item being tested, which is relatively simple to use, and which is ergonomic in design and operation.  
           [0002]    In particular, this invention relates to battery testers as commonly used for testing dry cell batteries. The term battery may be used collectively in the present context to include reference to single as well as multiple cells. The widespread use of batteries in consumer appliances, such as portable AM/FM radios, CD players, MP3 players, watches, calculators, hearing aids, PDA&#39;s, toys, games, etc., has given rise to a significant demand for devices for testing them. Furthermore, it is noted that some of the batteries that need to be tested, such as the small “button” cells which are increasingly being used for powering more and more electronic devices, can pose particular problems, given their small size, for the elderly to manipulate. This can be particularly distressing given that these batteries are of the type that are generally used in hearing aids.  
           [0003]    In addition, many bulbs and fuses are likewise used in everyday household and automotive applications. Just as it is not possible to determine the condition of a battery by looking at it, it is likewise impossible (in many cases) to determine the condition of a bulb or fuse merely by looking at it. Small bulbs, such as those used in Christmas light strings, are often colored and use small filaments, so it is not easy to know if the filament is broken or burned out by observation. As another example, it is difficult to determine if a small Halogen “pin” bulb is burned out or not because the filaments inside these bulbs are typically difficult to observe through the relatively thick glass of the bulb. In addition, some small automotive fuses are hard to “read” by observation. These examples underscore the need for a simple bulb and fuse tester.  
           [0004]    With respect to the testing of a bulb or fuse, it is noted that both of these devices are essentially “closed circuit” devices. A bulb has a very thin wire called a filament inside a protective glass shell. The filament gets very hot when current is passed through it. When it gets hot, it glows to produce visible light. When the filament burns out or is broken, then of course current cannot pass through the filament and therefore it will not produce light. A fuse works in a similar manner, but with the difference that the wire inside a fuse is relatively large or thick and is sized to carry a certain amount of high current before it melts and opens the circuit, interrupting the flow of current. A fuse is not intended to glow and produce light. Instead, the material used in a fuse is designed to melt when the current flowing in a circuit surpasses the design limit of the fuse wire, at which time it interrupts the current flow and causes an open circuit. The fuse thus sacrifices itself to protect other more sensitive and expensive components in the circuit, including the circuit wiring.  
           [0005]    To test a bulb or fuse, therefore, a circuit is necessary which is able to test the “continuity” of the device. To do so, the circuit must have a source of current. Therefore, a “continuity” tester is normally designed to use an internal voltage source, usually some sort of battery, that may be used to cause a small current to flow through the bulb or fuse when it is placed in the test circuit. In addition to the battery, a galvanometer movement (a small meter with a pointer that is deflected when current flows through the meter) is also normally used in the test circuit to measure the amount of current passing through the bulb or fuse. If the bulb or fuse is acceptable for use, then the current passing through the bulb or fuse causes the galvanometer to deflect (or light up a light on the meter) to represent this fact. A Light Emitting Diode (LED) can be used as the light in such circumstance to indicate the “good” or “bad” status of the bulb or fuse if desired.  
           [0006]    As mentioned above, it is also frequently desired to have a tester which accurately tests the condition of a battery. Such accurate testing can generally not be accomplished using a simple open circuit-type terminal voltage tester, instead requiring a load-based tester. Load-based testers are considered an improvement over less-expensive open circuit testers in that load-based testers are designed to measure the closed circuit battery terminal voltage under a load. In contrast, most inexpensive open circuit battery testers merely measure the open circuit battery terminal voltage with no load. And while such testers do not generally require the use of a complicated electronic circuit, integrated circuit (IC), or a microprocessor, thereby making them relatively inexpensive to design and make, the results obtained using such testers are not nearly as accurate or consistent as the results obtained using a load-based battery tester.  
           [0007]    More specifically, open circuit-type testers are relatively limited in value because they do not test a battery under a realistic “load” condition. Under a load, the terminal voltage of a battery will decrease to a much greater extent than if no load is applied. The state of the battery terminal voltage under load will provide a much more meaningful measure of how much useful life is remaining in a battery. However, as noted above, load testers, because they must apply a given load that is dependent on the properties of the battery being tested, normally require more sophisticated electronic circuits than open circuit testers.  
           [0008]    In practice, a load-based battery tester places a resistive load across the terminals of the battery to be tested and then measures the drop in terminal voltage as a result of the applied load. The remaining life of the battery is then a measure of the relative drop in terminal voltage under the applied load (closed circuit voltage). The results are calculated on the basis that every battery has a milliampere hour (mAh) rating from the manufacturer. A fully charged battery exhibits a maximum terminal voltage and a maximum mAh capacity. As the battery is used and becomes discharged, the terminal voltage begins to drop. At some point, called the cutoff voltage, the battery can no longer provide sufficient electrical energy to power an electronic device. Thus, the remaining useful life of a battery can be determined by measuring the terminal voltage under a given load. This voltage will begin at a maximum voltage (fully charged) and end at the cutoff voltage where the battery is “dead” or fully discharged. At closed circuit voltages in between these extremes, the percent of battery life remaining can be scaled and appropriately indicated by a meter or lights.  
           [0009]    More specifically, the circuit in a load tester may be designed to cause a meter to deflect a given amount or cause small Light Emitting Diodes (LEDs) to illuminate at certain voltage thresholds designed into the circuit. If there is virtually no voltage drop under a test load, the battery should read as “good”. If the battery drops to the cutoff voltage specified by the battery manufacturer, then the tester should indicate that the battery is “bad” and should be changed. Thresholds in between these extremes can be calibrated to show various levels of remaining battery life.  
           [0010]    In addition to testing battery life, as noted above, it is also sometimes desired to have a testing device that is capable of testing the general condition of light bulbs and/or fuses.  
           [0011]    Accordingly, there is a need for compact, economical testers capable of simply and easily testing a range of batteries varying size and/or voltages, light bulbs, and/or fuses and providing and accurate indication of condition of the tested device to a user thereof.  
         SUMMARY OF THE INVENTION  
         [0012]    The present invention provides an improved combination battery, light bulb, and fuse tester. In particular, the present invention provides a novel battery, light bulb, and fuse tester which is easy to use, especially for elderly individuals, which provides accurate results, and which is inexpensive to produce. According to the invention, the battery tester includes a novel battery testing probe mechanism. Preferably, such a probe mechanism may be comprised of two pincer-like probe arms which may be easily manipulated to clamp a battery, fuse or light bulb to be tested between electrical contacts located therein. More preferably, the probe arms may include a resiliently biased gearing mechanism in order to easily move the probe arms towards and away from one another. The probe arms may be controlled by an actuator, the actuator preferably being a resiliently biased trigger operatively connected thereto.  
           [0013]    In a preferred embodiment, the combination battery, light bulb, and fuse tester of the present invention would include a switch so that the tester could be used to measure both large (cylindrical type) or small (button or coin) batteries. Such a switch may be used to so that the testing circuit applies the desired resistive load depending on the battery size. Preferably, the testing circuit is an integrated circuit that may be used to apply the proper load to the battery type selected. The load can be applied for the entire time the battery is connected or it can be timed as is known in the art. Of course, to the extent applicable, the present invention is equally applicable for use with both the load-based and open circuit-type battery testers discussed in detail above.  
           [0014]    In a preferred embodiment, a series of transistors may be integrated into the circuit to turn on appropriate LEDs to indicate the condition of the battery. For example, RED, AMBER or GREEN LEDs may be used to indicate “bad”, “low”, “good” battery conditions depending on what the battery terminal voltage is for a given battery type being tested. In order to produce a highly sensitive tester, a set of potentiometers may be built into the integrated circuit for “trimming” each tester circuit to the desired cut off voltage. In such a set-up, a single potentiometer may be used for each LED circuit thereby allowing the load resistance to be set within a range that is closer and more accurate than any range that would be possible without the use of trimmable potentiometers. In this preferred embodiment, the circuits maybe tuned or “trimmed” at the factory using sensitive test equipment to desired threshold voltages, and then locked in place using a dab of paint or adhesive. In this way, a high degree of accuracy and repeatability may be calibrated into a preferred embodiment of a battery tester in accordance with the present invention.  
           [0015]    In a preferred embodiment, the threshold voltages designed into the tester to trigger the various LED&#39;s may be as follows:  
                                                                                 Tested Battery   RED LED   AMBER LED   GREEN LED                                    1.   1.5 V   &lt;1.1 V   1.1 ≦ X &lt; 1.2 V   1.2 ≦ X       2.   3.0 V   &lt;2.2 V   2.2 ≦ X &lt; 2.3 V   2.4 ≦ X       3.   9.0 V   &lt;6.6 V   6.6 ≦ X &lt; 7.2 V   7.2 ≦ X       4.   Bulb/Fuse   BAD   Not Applicable   GOOD                  
 
           [0016]    Also in a preferred embodiment, a tester in accordance with the present invention maybe provided with an internal circuit to test the efficacy of the tester&#39;s internal batteries for use in applying the desired load. Such a circuit may indicate the low condition of the batteries in many ways. For example, the circuit could be designed to light two LEDs at the same time or to flash the LEDs to indicate to the user that the internal batteries need replacing.  
           [0017]    In a further preferred embodiment, the tester of the present invention may include a feature for facilitating the contacting of the battery poles to the electrical contacts on the probe ends. In particular, given that batteries generally have cases made of one type of steel or another, the use of a magnetic electrical contact for one of the probes can facilitate the testing of batteries, especially for those without particularly nimble fingers. This magnetic electrical contact feature makes the invention especially easy to use over prior art battery testers in that the user does not need to carefully place a small battery into a slot, receptacle, or otherwise exhibit excellent eye-hand coordination in order to use the tester. Furthermore, there is little possibility of the battery falling out of the tester once the battery is placed against the magnetic tip.  
           [0018]    It is noted that in an embodiment of the present invention including this magnetic contact feature, it may be preferred that only one electrical contact be selectively made from magnetic material. The other electrical contact should be made from a non-magnetic material, thereby preventing the electrical contacts from being held together by a magnetic force which would needlessly make it more difficult to open the probe arms with the handle trigger in order to place a battery, bulb or fuse between the electrical contacts. Of course the use of either one or two electrical contacts having magnetic properties would still be considered within the scope of the invention.  
           [0019]    While the battery test circuit used in the present invention need not be any particular battery testing circuit, it is preferred that an electronic load-based battery testing circuit be used. An example of types of electronic battery testing circuits that could be operable in the present invention include the battery testing circuits disclosed in U.S. Pat. Nos. 6,456,045, 5,914,605, 5,376,887, the contents of which are herein incorporated by reference, among others well known in the battery testing art.  
           [0020]    Other objects and advantages of the invention maybe apparent to one of ordinary skill in the art upon reference to the drawings, specification and appended claims herein and are considered within the scope of the present invention. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0021]    [0021]FIG. 1 illustrates a front perspective view of one embodiment of a combination battery, light bulb, fuse tester in accordance with the present invention;  
         [0022]    [0022]FIG. 2 illustrates a top plan view of the combination tester of FIG. 1;  
         [0023]    [0023]FIG. 3 illustrates a side elevation view of the combination tester of FIG. 1;  
         [0024]    [0024]FIG. 4 illustrates an interior view of some of the electronic components for use in accordance with the combination tester of FIG. 1;  
         [0025]    [0025]FIG. 5 illustrates a detail view of the probe arm mechanism for use in accordance with the combination tester of FIG. 1 in a closed position;  
         [0026]    [0026]FIG. 6 illustrates a detail view of the probe arm mechanism for use in accordance with the combination tester of FIG. 5 in an open position. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0027]    The present invention provides a combination battery, light bulb, fuse tester  10 . In particular, the present invention provides a novel battery, light bulb, and fuse tester  10  which is easy to use, especially for elderly individuals, which provides accurate results, and which is inexpensive to produce. According to the invention, as best seen in FIG. 4, the battery tester  10  includes a case  12  housing a novel battery testing probe mechanism  14  comprised of two pincer-like probe arms  18 , 20  which may be easily manipulated to clamp a battery, fuse or light bulb (not shown) to be tested between electrical contacts  22 ,  24  located thereon.  
         [0028]    Preferably, as best seen in FIGS. 5 and 6, the probe arms  18 ,  20  include a resiliently biased gearing mechanism  26  in order to easily move the probe arms  18 ,  20  towards and away from one another. The probe arms  18 ,  20  are controlled by an actuator  28 , the actuator  28  preferably including a resiliently biased trigger  32  operatively connected thereto.  
         [0029]    More preferably, the resiliently biased gearing mechanism  26  comprises a resiliently biased trigger  32  having a first rack  36  positioned on an upper surface  38  thereof, a pinion gear  40 , a second rack  42 , including a set of lower teeth  44  and oppositely opposed sets of upper gear teeth  46 ,  48 . Additionally, in such embodiment, the probe arms  18 ,  20  each include a set of gear teeth  50 ,  52  molded on the lower portion of each. The probe arms  18 , 20  also preferably include pivot axles  54 ,  56  to hold the probe arms  18 ,  20  in a fixed, pivotable arrangement. Additionally, in this embodiment, it is preferable that the second rack  42  preferably include an anchoring member, which, in particular, may be comprised of a slot  60  positioned between the oppositely opposed sets of upper teeth  46 ,  48  for slidably receiving an anchoring post  62  molded or attached to the tester  10  case  12 .  
         [0030]    In the preferred gearing mechanism  26  disclosed herein, the gearing members are preferably arranged such that the first rack  36  engages the pinion  40 , the pinion  40  engages the lower teeth  44  of the second rack  42 , and the upper teeth  46 ,  48  of the second rack engage the gear teeth  50 ,  52  molded on the lower portion of the probe arms  18 ,  20 . Additionally, it is preferred that the trigger  32  of the actuator  28  include a slot  64  formed in both the upper and undersides of the trigger  32  to slidably receive associated ribs (not shown) formed in the upper and undersides of the case  12 . Finally, in a preferred embodiment, resilient biasing members are used to bias the probe arms  18 , 20  to a normally closed position. Such biasing members may be provided in many ways, one way being the way shown best in FIG. 5. In particular, at least one helical spring  66 , and preferably a second  68 , may be provided and seated in associated cylindrical seats  70 ,  72  formed in the trigger  32 . The helical springs  66 ,  68  are selected so that they bias the trigger  32  to an outward position by pressing against the inside of the case  12  when the trigger  32  is depressed. An additional biasing force may be provided by a helical spring  74  which is provided to attach between the probe arms  18 ,  20 . The helical spring  74  is chosen so that it biases the probe arms  18 ,  20  towards each other.  
         [0031]    In the embodiment disclosed above, the actuation of the probe arms  18 ,  20  may be accomplished as follows. The user of the tester  10  depresses the trigger  32  inwardly. The movement of the trigger  32  causes the first rack  36  to move laterally, thereby causing the pinion  40  to rotate accordingly. The movement of the pinion  40  forces the second rack  42  to move vertically upward about the anchoring post  62 . This movement then causes the upper gear teeth  46 ,  48  to mesh with the probe arms  18 ,  20  respective gear teeth  50 ,  52 , thereby causing the upper portions of the probe arms  18 ,  20  to rotate away from each other about their respective pivot axles  54 ,  56 . Releasing of the trigger  32  causes the probe arms  18 ,  20  to return to the normally-closed position due to the biasing forces provided by helical springs  66 ,  68 , and helical spring  74 . Of course, it should be noted that there are many additional mechanisms that may be used to rotate, or even translate, the probe arms of the present invention away from each other such that may clamp a battery, light bulb, or fuse therebetween to test. While these methods and mechanisms are not specifically disclosed herein, there use and incorporation in accordance with the invention would be considered within the scope of one of ordinary skill in the mechanical arts, and, as such, would be considered within the scope of the invention.  
         [0032]    In a preferred embodiment, the tester  10  of the present invention includes several user-friendly features. For example, as discussed above, the probe arms  18 ,  20  preferably include at least one electrical contact  22  that may be made of a magnetic material to help hold a battery, fuse or light bulb (not shown) being tested between the electrical contacts  22 , 24 . The magnetic electrical contact may be made of any suitable magnetic material, but is preferably made from a “permanent” magnetic material, and more preferably may be made of neodium. Neodium is a material known for exhibiting relatively high Gauss magnetic properties and is thus well suited to this application. A relatively small size magnetic electrical contact  22  can be made that is capable to holding a small button or coin battery in place against the electrical contact  22  of the tester.  
         [0033]    Also in a preferred embodiment, electrical contact  24  may be preferably made from a non-magnetic material, such as copper. Copper is preferable because not only is it considered a “non-magnetic”, but is naturally of a different color than, neodium, as used in a preferred embodiment in the magnetic electrical contact  22 . This is preferred in that it can be used to aid in differentiating the “+” and “−” electrical contacts. As a further aid to differentiation, the magnetic neodium electrical contact maybe zinc plated to help distinguish it from the copper “−” electrical contact.  
         [0034]    In another preferred embodiment of the present invention, the tester  10  preferably includes LED indicator lights  80 ,  82 ,  84  to indicate the status of the battery, light bulb or fuse being tested. In a preferred embodiment, there are three LED&#39;s employed in the first embodiment of the invention to show that a battery is “Good”, “Low”, or “Bad” and these LED&#39;s may be green, amber and red, respectively. Of course, it would be feasible within the scope of the invention to provide more LED&#39;s that could show a range of, for example, “Bad”, “10%-20%”, “ 20 %-50%”, “ 50 %-80%”, “80%-100%” . . . or some other set of ranges. Additionally, it would be within the scope of the invention to provide a meter to reflect the level of battery condition.  
         [0035]    Also, as discussed above, it is preferred that an electronic load-based battery testing circuit  86  be used in accordance with the invention. Also as discussed above, a conductivity circuit should be added for the embodiments of the invention which have a light bulb or fuse testing feature.  
         [0036]    In operation, the electrical contacts  22 ,  24  are designed to allow a variety of batteries, bulbs and fuses to be trapped between the “+” and “−” tester tips in a user-friendly manner. The contacts  22 ,  24  preferably are formed in a rounded shape to allow contact to be made with the corresponding terminals or contacts of batteries, bulbs and fuses no matter how close or far apart the probe arms  18 , 20 , and thus the