Abstract:
Methods and apparatus are disclosed for helping to prevent vehicular barrier gate arms from lowering in certain situations (such as if an obstruction such as a person is present), while not impacting the primary operation and function of the barrier arm (which is to lower the arm to prevent unauthorized vehicles from entering/exiting an area).

Description:
[0001]    This invention relates broadly to devices for helping to prevent vehicular barrier gate arms from lowering in certain situations (such as if an obstruction such as a person is present), while not impacting the primary operation and function of the barrier arm (which is to lower the arm to prevent unauthorized vehicles from entering/exiting an area). 
         [0002]    As indicated herein, the inventions disclosed herein can be used in a broad range of applications and provide many benefits. 
         [0003]    These and other embodiments will become readily apparent to those skilled in the art from the following detailed description of embodiments having reference to the attached figures, the invention not being limited to any particular preferred embodiment(s) disclosed. 
       BACKGROUND OF THE INVENTION 
       [0004]    Vehicular barrier gate operators are designed as traffic control mechanisms to restrict vehicular entry or exit from a designated area (such as a parking area). The “default” position of the barrier arm or arms typically is in the lowered (or down) position, at least during hours in which the access is being controlled. In order to provide the desired control over which vehicles enter and/or leave the controlled area, typically the arm(s) raise only when a vehicle has been granted entry or exit permission. Commonly, this permission is automated (via proximity cards or other technology). Following such authorization, once the barrier arm has raised and the vehicle passes through, typically the arm rotates or otherwise moves back to the “default” down position (again, to maintain the desired control of the designated area). 
         [0005]    In prior art systems, these “descending” barrier arms can injure individuals who may be passing beneath the arm as the arm moves downwardly (those persons may not be paying sufficient attention to the arm movement, may be trying to “beat” the arm&#39;s drop, or otherwise). Prior art efforts to prevent such injuries (i.e., to stop the arm from descending if a person is beneath the arm) is to install a photo-electric cell or similar sensor which, if the photo-beam is interrupted (blocked by the person&#39;s body) or the sensor is triggered, prevents the arm from further rotating down (or even reverses the downward movement). 
         [0006]    That prior art approach to the risk is less than ideal. Among other things, it can provide an opportunity for drivers of unauthorized vehicles to “beat” the gate by closely following behind an authorized vehicle—as the arm begins to descend after the authorized vehicle has entered the controlled area, the unauthorized vehicle interrupts the photo-beam and/or sets off the sensor just as a person/pedestrian does, which (like the pedestrian&#39;s interruption/triggering of the sensor) then prevents the arm from rotating down (or even reverses the downward movement). With the control arm stopped and/or raised again, the unauthorized vehicle can then enter/exit the controlled area, thus defeating the primary purpose of the gate/arm control system—to stop unauthorized vehicular traffic through the gate. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0007]      FIG. 1  is a perspective view of an exemplary controlled gate/arm installation, in which an arm  1  allows an authorized vehicle  2  to enter (or exit, depending on the installation/embodiment), but also (undesirably) allows a tailgating unauthorized vehicle  3  to enter (or exit) by closely following the authorized vehicle  2 . The arm motion is indicated by arrow  4 . 
           [0008]      FIG. 2A  is one of the many embodiments of a controlled access gate constructed in accordance with the current invention. The view and most elements are similar to those in  FIG. 1 , but among other things,  FIG. 2A  illustrates how an unauthorized vehicle  3  will NOT stop or reverse the downward motion of arm  1 —instead the arm motion  5  continues downward despite the exit attempt by the unauthorized vehicle  3 . 
           [0009]      FIG. 2B  is virtually the same as  FIG. 2A , but illustrates how a pedestrian will cause the arm motion  6  to occur (very similarly to the arm motion  4  of  FIG. 1 ). 
           [0010]      FIG. 3  is a prior art drawing illustrating one of the types of vehicle sensors (an induction loop) that may be utilized as part of the present invention. 
       
    
    
     DETAILED DESCRIPTION OF EMBODIMENTS 
       [0011]    The inventions disclosed herein can be used in a broad range of applications and provide many benefits. Embodiments of the present invention will now be described with references to the accompanying figures, wherein like reference numerals refer to like elements throughout. 
         [0012]    Persons of ordinary skill in the art will understand that the apparatus of the invention and variations of its many methods can be practiced using any of a wide variety of suitable processes and materials. 
         [0013]    As illustrated in  FIGS. 2A and 2B , in one embodiment of the invention, a photo-beam system or other sensor is used to detect non-vehicular obstructions (such as persons) beneath the barrier arm, and absent some other signal (such as described below), that sensor will function in much the same manner as in the prior art systems discussed herein (interruption of the photo-beam will cause the arm  1  to reverse its downward motion, as shown by arrow  6  in  FIG. 2B . In this embodiment of the invention, however, an additional sensing means is provided (such as a vehicular inductance loop system such as shown in  FIG. 3 , which is preferably located operably generally under the unauthorized vehicle  3 ′s position in  FIG. 2A ) to detect the presence of a vehicle beneath the barrier arm. Persons of ordinary skill in the art will understand that this additional sensing means can take any of a range of forms and technologies, but preferably functions to distinguish whether the interruption of the photo-beam has been caused by (a) a vehicle or (b) a person or persons (or even more broadly, something OTHER than a vehicle). If the latter (a person, something OTHER than a vehicle, etc.), the embodiment preferably does stop or reverse the motion of the arm  1 , as described above, helping to ensure that the person is not struck by the descending arm  1 . If the former, however, the embodiment preferably does NOT stop or reverse the motion of the arm  1  (see illustrative arrow  5  showing this continuing downward arm motion), and instead the arm  1  continues its downward motion into the default closed position, so that the integrity of the “controlled area” is maintained. 
         [0014]    Persons of ordinary skill in the art will understand that, for embodiments using an inductive loop vehicle detector system, any of a wide range of inductive loop vehicle detector systems can be utilized. One example is illustrated at http://www.marshproducts.com/pdf/Inductive%20Loop%20Write%20up.pdf, and includes a loop that is: 
         [0015]    “ . . . a continuous run of wire that enters and exits from the same point. The two ends of the loop wire are connected to the loop extension cable, which in turn connects to the vehicle detector. The detector powers the loop causing a magnetic field in the loop area. The loop resonates at a constant frequency that the detector monitors. A base frequency is established when there is no vehicle over the loop. When a large metal object, such as a vehicle, moves over the loop, the resonate frequency increases. This increase in frequency is sensed and, depending on the design of the detector, forces a normally open relay to close. The relay will remain closed until the vehicle leaves the loop and the frequency returns to the base level. The relay can trigger any number of devices such as an audio intercom system, a gate, a traffic light, etc.” 
         [0016]    Other details of such inductive loop technology are discussed that cited article/posting on the Internet. 
         [0017]    In certain embodiments, preferably some automated signal processing and logic such as a computer program/logic (code) is provided to receive the sensor input(s) and make the determination as to whether the photo-beam interruption is being caused by a vehicular or non-vehicular obstruction, and to thereafter (relatively immediately) cause the barrier arm system (and specifically arm  1 ) to move (and/or stop) in an appropriate manner. As indicated above, preferably the system prevents the arm  1  from rotating down if a non-vehicular obstruction is present, but allows the barrier arm  1  to rotate down if a vehicle is present. In short, the system differentiates between (a) a non-vehicle interrupting the photo-beam (and thereafter prevents the arm  1  from further rotating down) and (b) a vehicle interrupting the photo-beam (in which case the system preferably allows the arm  1  to continue to rotate or otherwise move down to a default closed position). 
         [0018]    The system of the invention thus provides a means to help prevent accidents to pedestrians who inadvertently (or intentionally) find themselves in a controlled access traffic lane. As a further safety feature in certain embodiments, the computer logic (code) also can monitor for the presence of, and correct operation of, the photo-beam system/inductive loop system, on each cycle of the barrier arm  1  (each time the arm  1  operates to “open” and allow an authorized entrance or exit). If such monitoring indicates that the photo-beam system and/or the inductive loop system are not connected to the barrier arm operator and/or are not otherwise operating correctly, the system can be set to “deactivate” any motion by the barrier arm  1 , or to operate in some other “safe” manner. For example, the system can be programmed so that, if an electric fault exists in the photo-beam system and/or the inductive loop system, the barrier arm operator will not be allowed to rotate the barrier arm  1  to the down position. 
         [0019]    The present invention is described herein with reference to the accompanying Figures, which serve as illustrations of some of the many embodiments in which the invention may be practiced. Subject to the context and other factors (including for example the understanding of persons of ordinary skill in the arts relevant to the inventions), generally in those Figures and references similar reference numerals refer to similar or identical elements throughout this description. 
         [0020]    Those Figures and references, and the other terminology used in these descriptions, are not intended to be interpreted in any limited or restrictive manner, simply because it is being utilized in conjunction with a detailed description of certain embodiments of the invention. Furthermore, various embodiments of the invention (whether or not specifically described herein) may include one or more of the novel features disclosed herein, no single one of which (a) is necessarily solely responsible for any particular desirable attribute(s) of the inventions or (b) is essential to practicing the inventions described. 
         [0021]    For the purpose of summarizing the invention, certain objects and advantages have been described herein. It is to be understood that not necessarily all such objects or advantages may be achieved in accordance with any particular embodiment of the invention. Thus, for example, those skilled in the art will recognize that the invention may be embodied or carried out in a manner that achieves or optimizes one advantage or group of advantages as taught herein without necessarily achieving other objects or advantages as may be taught or suggested herein. 
         [0022]    The apparatus and methods of the invention have been described with some particularity, but the specific designs, constructions, and steps disclosed are not to be taken as delimiting of the invention. A wide range of modifications and alternative structures and steps for practicing the invention will make themselves apparent to those of ordinary skill in the art, all of which will not depart from the essence of the invention, and all such changes and modifications are intended to be encompassed within the appended claims. 
         [0023]    Although the examples of the many various methods of the invention are described herein with steps occurring in a certain order, the specific order of the steps, or any continuation or interruption between steps, is not necessarily intended to be required for any given method of practicing the invention.