Patent Publication Number: US-8112938-B2

Title: Gate system with automatic locking and unlocking feature

Description:
TECHNICAL FIELD 
     The present invention relates to a controlled gate system with automatic locking and unlocking feature and particularly, but not exclusively, for use in shopping establishments. 
     BACKGROUND ART 
     A multitude of gate systems are known whereby to restrict passage or control the passage of people in specific areas. Some of these systems are in the form of complicated barriers or turnstile systems or simply a single arm which is pivotally connected at one end by a pivoting mechanism permitting passage in a single direction. An example of such single arm systems is disclosed in U.S. Pat. No. 5,561,520. Many of these systems are complex in design and are therefore subject to wear and breakage and require frequent maintenance. This can be a nuisance particularly if such gates become broken and locked preventing a person from entering into an establishment such as a supermarket. 
     Another disadvantage of known prior art one-way self-closing gates is that many of these gates permit passage in only a single direction and in an emergency situation it is not possible or very difficult to exit an establishment through these barriers. Another disadvantage of some of these entrance gate systems is that they do not provide alarms if they are misused such as person trying to exit therethrough and therefore require periodic surveyance. Still further, some of these entrance gate systems permit easy undetected exit therethrough by a person maintaining the barriers or a pair of barriers in a double-gate system, in an open position for a long period of time permitting exit therethrough of another person and even the passage of shopping carts. 
     SUMMARY OF INVENTION 
     It is therefore a feature of the present invention to provide an entrance gate system which substantially overcomes the above-mentioned disadvantages of the prior art. 
     Another feature of the present invention is to provide a controlled gate system which is simple in construction and which provides for controlled passage therethrough in a single direction or in opposed directions during alarm conditions or during other conditions when necessary to do so by personnel of an establishment where the entrance gate system is provided. 
     Another feature of the present invention is to provide a controlled gate system having an automatic locking and unlocking feature. 
     Another feature of the present invention is to provide a controlled gate system equipped with audible and visual alarms to regulate the passage of people through the entrance gate system and to indicate abnormal conditions. 
     Another feature of the present invention is to provide a controlled gate system having a controller which is interfaced with a general alarm system of an establishment to permit passage in opposed directions during certain alarm conditions. 
     According to the above features, from a broad aspect, the present invention provides a controlled gate system comprising a barrier arm pivotally connected to a first fixed support. Motion detection means is secured to a second fixed support spaced a predetermined distance from the first fixed support and in alignment therewith to create a restricted passageway with the barrier arm normally resting in an obstructing position within the passageway. Arresting means is provided for arresting the barrier arm at the obstructing position. Control means is provided to position the arresting means at an engaged or disengaged position to arrest or release the barrier arm from pivotal movement. Stopper means is provided to restrict the arc of displacement of the barrier arm from the obstructing position to a non-obstructing position to permit passage through the passageway in a single direction when the arresting means is at the disengaged position. 
     According to a further broad aspect of the present invention the motion detection means is constituted by a second barrier arm having a sensing means associated therewith to sense the displacement of the second barrier arm in the direction of the passageway whereby to disable the arresting means to permit both barrier arms to be pivoted in an open direction for the passage through the passageway and within a predetermined time period after which an alarm condition is sound. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
       A preferred embodiment of the present invention will now be described with reference to the accompanying drawings in which: 
         FIG. 1  is a perspective view illustrating a double-gate system constructed in accordance with the present invention and having two spaced-apart barrier arms secured at a predetermined distance therebetween to create a restricted passageway with other barrier rods; 
         FIG. 2  is a perspective view showing the construction of the fixed supports to which the two barrier arms are pivotally connectable, only one barrier arm herein shown assembled to one of the posts; 
         FIG. 3  is an enlarged perspective view of the bottom support bracket as identified by the circle portion of  FIG. 2 , identified with the designation “FIG.  3 ”, and associated with the inner support column of the entrance gate system; 
         FIG. 4  is an enlarged view of the circle portion of  FIG. 2 , identified by the designation “FIG.  4 ”, and associated with the outer support column of the entrance gate system; 
         FIG. 6  is a further perspective view showing the arresting latch in a disengaged position; 
         FIG. 7  is a perspective view showing the top end of the vertical tubular support member of the barrier arm with a further stopper ring secured thereto and in line with a stopper element to restrict the rotational movement of the vertical tubular support member; 
         FIG. 8  is a perspective view of a bottom portion of the vertical tubular support member of  FIG. 7  showing the relationship of the stopper ring with respect to the stopper element; 
         FIG. 9  is a section view showing the construction of the barrier arm and its vertical tubular support member and having a ramp follower member with a sloped formation secured therein; 
         FIG. 10  is an enlarged view of the circle portion “C” of  FIG. 9  showing the relationship of the sloped formation with respect to a stationary ramp formation secured to a stationary vertical shaft held captive between the brackets of the support columns; 
         FIG. 11A  is a side view of the vertical shaft; 
         FIG. 11B  is a perspective view of the vertical shaft showing the construction features of the stationary ramp formation; 
         FIG. 12A  is a side view of the outer support column showing the position of the actuator housing; 
         FIG. 12B  is a front view of  FIG. 12A  illustrating the shape and location of the displaceable support rod to which the stopper elements are connected and displaceable; 
         FIG. 12C  is a section view along section line D-D of  FIG. 12B  showing the position of the actuator within the outer support column; 
         FIG. 13  is a perspective view of the actuator and its attachment brackets; 
         FIG. 14  is a front view of the displaceable support rod shown in  FIG. 12B ; 
         FIG. 15  is an enlarged perspective view of the bottom end of the displaceable support rod shown in  FIG. 14 ; 
         FIG. 16  is an enlarged section view showing the connection of the actuator in the support column and its connection to the displaceable support rod outside the column; 
         FIG. 17  is a perspective view of the rod retention plate secured to the attachment bracket secured to the end of the displaceable arm of the actuator; 
         FIG. 18  is an enlarged view showing the interconnection of the attachment bracket with the displaceable support rod; 
         FIG. 19  is a perspective rear view of the entrance gate system of the present invention and partly fragmented to show the securement of the actuator and other controller elements within the support columns; 
         FIG. 20  is a block diagram showing the interrelationship between the controller and associated devices of the entrance gate system as well as with local power supplies and general alarm systems provided by an establishment in which the entrance gate system is secured; 
         FIGS. 21 to 25  are time-flow diagrams illustrating the operation of the entrance gate system under different conditions; 
         FIG. 26  is a perspective view showing the entrance gate system of the present invention comprised of a single barrier arm assembly; and 
         FIG. 27  is a perspective view showing a further embodiment wherein each barrier arm assembly is provided with an arresting latch. 
     
    
    
     DESCRIPTION OF PREFERRED EMBODIMENTS 
     Referring now to the drawings and more particularly to  FIG. 1 , there is shown generally at  10  a gate system constructed in accordance with the present invention. The gate system will be referred to herein as an entrance gate system to an establishment, but it may also be used in other applications. As hereinshown there are two entrance gate systems  10  and  10 ′ secured in a side-by-side position. Only one of these systems will be described herein as these are constructed in an identical manner. The entrance gate system  10  is comprised of a first fixed support  11 , herein in the form of a support column  12  to which a barrier arm assembly  13  is pivotally connected. A motion detection means which is hereinshown in the form of a second support column  12 ′ is secured at a predetermined distance from the first support column  12  and it is provided with a motion detection means which is herein illustrated in the form of a second barrier arm assembly  13 ′. It is also envisaged that the second support column  12  may be any other type of support in which a motion detector may be secured to detect the passage of a person entering the entrance gate system  10  of the present invention. The support columns  12  and  12 ′ are secured in side alignment and create a restricted passageway  14  to permit the passage of people in the direction of arrow  15  from the outer support column  12 ′ to the inner support column  12 . 
     As hereinshown the barrier arm assemblies  13  and  13 ′ normally rest in an obstructing position across the passageway  14 , herein transversely at substantially 90° therein. 
     As also shown in  FIG. 1  and conventional with these passageways, tubular barrier rods  16  are conveniently secured with respect to the support columns to provide a restricted passageway. All of the columns and barrier rods are rigidly anchored to the floor  17  of an establishment to permit one-way restricted passage. 
     With additional reference now to  FIGS. 2 to 11B , there will be described the construction and operation of the barrier arm assemblies  13  and  13 ′ and their securement to their support columns  12  and  12 ′. As shown in  FIG. 2 , the inner support column  12  and outer support column  12 ′ are hollow vertical support tubes each having a securement base  18  to be anchored into the floor  17 . These support columns  12  and  12 ′ are provided with a top support bracket  19  and  19 ′, respectively and bottom support brackets  20  and  20 ′ respectively. The bottom support bracket  20  of the inner support column  12  is of different construction than the bottom support bracket  20 ′ of the outer support column  12 ′ as better illustrated in  FIGS. 3 ,  5  and  6 . 
     As shown in  FIGS. 3 ,  5  and  6 , the bottom support bracket  20  of the inner column  12  is provided with two spaced-apart horizontal support walls, namely a bottom support wall  21  and an upper support guide wall  22 . The upper support guide wall  22  is provided with a U-shaped slot  23  to receive a lower end portion of a vertical tubular support member  24  (see  FIG. 6 ), forming part of the barrier arm assembly  13  and in close guided fit therein. A passage  8  permits passage of a stopper element  45  to a non-engaging position. A hole  25  is provided in the bottom support wall  21  and aligned centrally with the U-shaped slot  23  whereby to secure the lower end of a stationary vertical shaft  35  disposed within the tubular support member  24 , as will be later described. 
     Secured to the bottom support wall  21  is a solenoid  26  which is operated by a signal received from a sensor  27 , as shown in  FIG. 8 , which detects the displacement of a stopper ring  28  secured to the bottom end of the vertical tubular support member  24 , as shown in  FIG. 6 . The solenoid  26  is provided with an energizable coil  29  which actuates a solenoid rod  30  connected to an arresting latch  31  through a pivotal linkage  32  whereby to position the arresting latch  31  at an engaged obstructing position with respect to the stopper ring  28 , as shown in  FIG. 5 , and at a disengaged, non-obstructing position as shown in  FIG. 6 . The solenoid  26  actuated latch  31  constitutes a displaceable arresting means to arrest the barrier arms  9  of the barrier arm assembly  13  at the obstructing position within the passageway  14 . 
     The bottom support bracket  20 ′ of the outer support column  12 ′, as shown in  FIG. 4 , is not equipped with a solenoid and latch and it supports the bottom end of the vertical tubular support member  24 ′ of the second barrier arm assembly  13 ′ for rotation from an obstructing position as shown in  FIG. 1  to an open position inwardly of the passageway in the direction of arrow  15  and displaceable substantially 90° therewithin to permit free access to the passageway  14 . The bracket  20 ′ also has a bottom support wall  21 ′ and an upper support wall  22 ′ provided with a U-shaped slot  23 ′ to receive the vertical tubular support member  24 ′ as shown in  FIG. 4 . The vertical tubular support member  24 ′ is also provided with a stopper ring  28 ′ but constructed differently as will be described further on. 
     Referring now to  FIGS. 9 to 11B , there is shown the construction of the barrier arm assemblies  13  or  13 ′. The assemblies each comprise a stationary vertical shaft  35  which is of rod shape as shown in  FIG. 11B  and having a threaded bore  36  at a top end thereof for receiving a fastener  36 ′ therein, see  FIGS. 7 and 9 , to secure the top ends of the shafts  35  immovable in their respective top support brackets  19  and  19 ′. The bottom end has a connecting rod  38  which is positioned in the hole  25  in the bottom support walls  21  and  21 ′ of the support bracket  19 , as shown in  FIG. 7  whereby to secure the shafts  35  immovable in a vertical position. The stationary vertical shaft  35  is further provided with an upwardly angulated stationary ramp formation  37  spaced from an upper end  38  of the stationary vertical shaft  35  and secured to the shaft by fasteners  39 . As shown in  FIG. 11B , the stationary ramp formation  37  has opposed angularly shaped engageable guide surfaces  40 . 
     Referring now to  FIGS. 9 and 10 , it can be seen that the vertical tubular support member  24  is provided at an upper end thereof with a ramp follower member  41  and as shown in  FIG. 10 , the vertical tubular support member  24  is adapted to be positioned over the stationary vertical shaft  35  in the direction of arrow  43  and not yet in full position wherein the slope formation  42  rests on the engageable guide surfaces  40  of the stationary ramp formation  37 . Accordingly, when the barrier arm  9  is displaced from its obstructing position, as shown in  FIG. 1 , towards a non-obstructing position by a pushing force, the ramp follower slope formation  42  is caused to be displaced upwardly by its frictional contact with the upwardly angulated stationary ramp formation  37  causing the vertical tubular support member  24  and the barrier arm  9  to move away from its obstructing position and rise as it is displaced from its obstructing position towards an open position. When the pushing force is released on the barrier arm the ramp follower member  41  will cause the vertical tubular support member  24  to descend by gravity over the stationary vertical support shaft  35  with the barrier arm  9  re-establishing its obstructing transverse position. Accordingly, the vertical tubular member  24  is axially rotatably supported over the stationary vertical shaft  35 . 
     With reference now more specifically to  FIGS. 5 to 8 , there is shown the construction of stopper means whereby to arrest the displacement of the barrier arms from their normally obstructing position, as shown in  FIG. 1 , to an open position in the direction of arrow  15 . As previously described, stopper rings  28  and  28 ′ are secured to the bottom end of the vertical tubular support members  24  and  24 ′, respectively, of the barrier arm assemblies  13  and  13 ′. The stopper ring  28  is provided with two spaced-apart abutment surfaces  44  and  44 ′ disposed at  1800  from one another, see  FIG. 5 . A stopper member  45 , see  FIGS. 3 and 5 , is positioned against the support column  12  and disposed for abutting engagement by the abutment surface  44  when the vertical tubular support member with the stopper ring  28  is rotated in the direction of arrow  15 , as shown in  FIG. 1 , to restrict the position of the barrier arm  9  to an open angle of 90° with respect to the vertical support column  12 . Similarly, as shown in  FIG. 7 , a further stopper ring  28 ″ is secured adjacent the upper end of the vertical tubular support member  24  but it has abutment surfaces  47  which are herein disposed at 90° angles from one another. The reason for this is that the abutment surface  40 ′ of the lower stopper ring  28  is disposed for abutment with the arresting latch  31  of the solenoid  26  when in an engaged position to arrest the opening of the barrier arm assembly  13  or more to arrest the rotation of the stopper ring  28  in the direction of arrow  46 . The upper ring  28 ″ will only permit 90° rotation of the vertical tubular support member due to the position of its abutment surfaces  47  engaging either side of an upper stopper member  45 ′. 
     As shown in  FIG. 8 , the bottom stopper ring  28 ′ of the vertical tubular support member  24 ′ of the second or outer barrier arm assembly  13 ′ is constructed identically with the upper stopper ring  28 ″ which is also provided at the upper end of its vertical tubular support member  24 ′. 
     Referring to  FIGS. 3 ,  4 ,  14  and  15 , it can be seen that the stopper members  45  and  45 ′ are secured at opposed ends of a displaceable support rod  48  which is a flat metal rod having opposed narrower extensions  49 , herein a bottom extension  49  which is longer than an upper extension  49 ′, see  FIG. 14 , and on which the stopper members, herein rectangular metal blocks having opposed parallel vertical arresting surfaces  45 ″ are immovably secured. The reason for the narrow extension  49  being longer is that the bottom support brackets  21  are double-wall brackets needing a longer extension as the displaceable support rod is axially displaceable whereby to position the stopper member  45  at an engaged position, as shown in  FIGS. 3 and 5 , and at a disengaged position wherein the stopper members are disposed through the top wall  22  and top wall  19  of the lower and upper support brackets  20  and  25 , to provide free axial rotation of the vertical tubular support member  24  and  24 ′ in emergency situations or when desired. The stopper rings of the tubular support members  24  and  24 ′ prevent the barrier arms  9  and  9 ′ from being pivotally displaced outwards in a direction opposite arrow  15  shown in  FIG. 1 . 
     With reference now to  FIGS. 12A to 12C , it can be seen that the tubular support columns  12  and  12 ′ are each provided with displaceable vertical support rods  48  and  48 ′, respectively, as previously described, on a face thereof facing the direction of the brackets, herein support brackets  20 ′ and  19 ′ of column  12 ′. Each displaceable support rod  48  and  48 ′ is connected to a respective actuator  50  which is housed within the columns  12  and  12 ′ in the actuator housings  51 , as shown in  FIGS. 12A and 12C . The actuator construction is illustrated in  FIG. 13 . The purpose of the actuators  50  is to displace the stopper members  45  and  45 ′ from their engaging position with the stopper rings  28  and  28 ′ in emergency situations. The actuators  50  have an electric motor  52  coupled to gearing or other type of drive (not shown) housed within the housing  53  to cause a displaceable arm  54  to move in and out of the arm housing  55 . With further reference to  FIGS. 17 and 18 , the displaceable arm  54  has an attachment bracket  56  at a free end thereof for securement to an attaching plate  57  which is secured to the support rod  48  through the hole  48 ′, see  FIG. 14 . Fasteners  57 ′ secure the plate  57  to the bracket  56 . A spacer block  57 ′ extends through openings  56 ′ of the plate  57  to connect thereto. The spacer block  57 ′ moves within a slot  58  provided in the front face  59  of the support column  12 ′, see  FIG. 18 , to cause the displaceable support rod  48  to move up and down in a guided fashion. The slot  58  is sufficiently long whereby to position the stopper members  45  and  45 ′ in a non-engaging position above their respective stopper rings to free the tubular support members  24  and  24 ′. 
       FIG. 19  shows the construction of the support columns  12  and  12 ′ and as hereinshown these columns are substantially of square cross-section but could also be of different cross-section. The back walls  60  and  60 ′ of these columns have removable section(s) whereby to secure the actuators  50 , wiring, etc. As shown in  FIG. 13 , the actuator is provided with an attachment bracket  59  at an upper end thereof to removably secure same in its respective support columns  12  and  12 ′. A control circuit is also provided in the upper ends of the inner support column  12  on a suitable support  61  (see  FIG. 19 ) and the top end of this support is provided with signaling means in the form of flashing LED lights and audible sound generating means to generate an alarm under alarm conditions as will be described later. Of course, both the inner and outer support columns  12  and  12 ′ could be provided with these alarm generating means which are obvious to a person skilled in the art. 
     With reference now to  FIG. 20 , there is shown a block diagram of the control means constituted by two controller modules  65  and  65 ′, one in each column, and their associated devices. The controller assemblies are concealed in the posts and the posts are provided with caps  62  and  62 ′ to prevent tampering. These caps and/or columns are provided with openings to render the visual and audible alarms effective. 
       FIG. 20  is a simplified schematic diagram of the wiring system and devices associated with the controller modules  65  and  65 ′. Controller module  65  is positioned within the inner support column  12  and controller module  65 ′ within the outer support column  12 ′. These controllers are provided with a power supply from a 120 volt outlet  63  of an establishment  64  where the entrance gate system  10  is installed. A DC voltage is supplied through an AC to DC converter  71  to provide a 12-volt DC supply to the controllers  65  and  65 ′. A battery back-up  70  is also provided in case of power failure. These establishments also have fire alarm systems  65  and an output connection  66  therefrom is also fed to the controllers  65  and  65 ′ whereby the controllers actuate the actuators  50  and  50 ′ when a specific alarm condition is detected to release the barrier arms from engagement. A programmable timer circuit, not shown, is also associated with the controller  65 ′ to set the time delay for normal passage in the passageway. Optical sensor  27 , as shown in  FIG. 8 , provides signals to the controller  65 . Another sensor  27 ′, associated with the inner support column  12 , also provides a signal to the controller  65 ′ to indicate the position of the inner barrier arm  9 . As hereinshown the solenoid  26  is also controlled by the controller  65 ′. 
     As shown in  FIG. 20 , a key switch connection  72  is provided to cause the controllers to actuate the actuators  50  and  50 ′ whereby to position the stopper elements to a non-engageable position whereby to free the barrier arms of both the inner and outer support columns whereby they can pivot in either direction from their normal obstructing position. As also herein illustrated both inner and outer support columns  12  and  12 ′ are provided with audible and/or visual alarms  73  and  73 ′. Sensor switches  74  and  74 ′ are conveniently located in their respective support columns whereby to sense the position of the stopper elements  45 , and namely the displaceable support rod  48  and provide signals to their respective controllers  65  and  65 ′. As previously mentioned, a timer circuit, not shown, is a programmable timer circuit and is adjustable whereby to adjust the time delay for the passage of persons within the passageway  14  in the direction  15  as shown in  FIG. 1 . 
     The entire system can be de-activated by the use of a key operated switch  72  or remotely through the alarm system of the establishment thereby permitting people to exit through the entrance gate system in case of fire or other such major emergencies. If the system is disengaged by use of a key it needs to be re-engaged by the key. Key slots, not shown, are provided on both of the support columns. If the system is disengaged by an alarm condition, there is provided a reset button on a supply panel to re-activate the system. 
     As shown in  FIG. 21 , if the barrier arm  9 ′ is pushed in the direction of arrow  15 , this automatically disengages the alarm systems  73  and  73 ′ and disengages the solenoid arresting latch  31  of the barrier arm  9 . When the barrier arm  9 ′ returns to its arresting position, as shown in  FIG. 1 , with a person now having entered the passageway  14 , the timer starts counting a programmed time lapse  92  while the person exits through the second barrier arm  9 . The system re-arms itself once the time delay  92  has expired. The time delay  92  is adjustable in the program. The barrier arm assembly  13  also cannot activate the alarms  73  and  73 ′ if the barrier arm  9  is opened and closed during the time delay. The alarms  73  and  73 ′ are automatically re-armed after the time delay. The diagram of  FIG. 21  illustrates this normal sequence of operation. 
     Referring now to  FIGS. 22 and 23 , there are illustrated alarm conditions. As shown in  FIG. 22 , if the barrier arm  9  of the inner barrier arm assembly  13  remains open when the system is armed, this being shown by the block extension  80 , the alarm circuits are armed and this triggers a visual and/or audible alarm, as shown by block  95 , provided in the support columns. This alarm  95  will stay on as long as the barrier arm  9  remains open, that is to say until it returns to its obstructing position. Such is illustrated in  FIG. 23 . 
       FIG. 24  depicts normal repetitive passage of people through the entrance gate system  10  of the present invention. As hereinshown when many people pass through the gate system one behind the other, the passage delay is too short to trigger the alarm system and such cannot be activated until the barrier arm  9  returns to its normal obstructing position. An alarm is triggered only if the barrier arm  9  is maintained open when the alarm is re-armed, as shown at  81 , after the time delay  92 . The blocks  82  illustrate the opening times of the barrier arm  9 ′ of the outer assembly  13 ′ whereas the blocks  83  show the conditions of the barrier arm  9  of the inner barrier arm assembly  13 . As hereinshown the barrier arm  9  has re-closed, as illustrated by block  83 ′ prior to the alarm system having been armed as illustrated by block  81  and no alarm is sound. 
     As shown in  FIGS. 24A and 24B , when the barrier arm  9 ′ of the outer barrier arm assembly  13 ′ is opened the solenoid is actuated and the barrier arm  9  is free to pivot. When the barrier arm  9 ′ re-closes as shown by block  84 , it actuates the timer  66  as shown by block  85 . This timer has no effect on the system if the barrier arms are open during the timer sequence as shown in  FIGS. 24A and 24B . When the barrier arm  9  returns to its obstructing position, as shown by block  86 , the controller engages the solenoid to lock the barrier arm  9  in its obstructing position at the time period  87 . The system is then re-armed as illustrated by the block  88 . If the barrier arm  9 , block  86 , remains open past the program delay, block  85 , then an alarm condition will be established until the barrier arm  9  returns to its closed position as shown at time period  89 . The system then becomes re-armed at this time period  89  as shown by block  90 . 
     As shown in  FIG. 25  it is possible that a person may start entering the passageway  14  and then decide not to enter as the barrier arm  9 ′ is pushed inwardly in the direction of the passageway. This situation is illustrated by block  91  wherein the barrier arm  91  has been pushed towards an open position. This automatically disengages the latch of the solenoid permitting the barrier arm assembly  13  to pivot inwardly of the establishment in the direction of arrow  25 ,  FIG. 1 . However, the arm  9  is not moved. After the programmed time delay, as illustrated by block  92 , the barrier arm  9 , which has not been displaced, is simply re-engaged by the latch  31  of the solenoid  26  and the alarm circuits  73  and  73 ′, illustrated by block  93  are re-armed. 
     When using optical light beams instead of the barrier arm  13 ′, two light beams are used one near the bottom and one near the top of column  12 ′. Both beams have to be interfered within a set time delay to disconnect the latch of the barrier arm  13 . The alarm system can be de-activated as previously described. 
     It is within the ambit of the present invention to provide any obvious modifications of the embodiment described herein provided such modifications fall within the scope of the appended claims. As previously described it is envisaged that the entrance gate system of the present invention may be comprised of a single barrier arm assembly  13 , as shown in  FIG. 26 , and that suitable sensing means may be provided at an entrance end of the passageway  14  to detect a person or a shopping cart or any object entering into the passageway and wherein such sensor would then automatically disengage the solenoid permitting the barrier arm assembly  13  to pivot. 
       FIG. 27  shows a further modification wherein the barrier arm assembly  13 ′ is also provided with a solenoid assembly  126  identical in construction and operation as the solenoid  26  associated with the barrier arm assembly  13 . The purpose of the solenoid assembly  126  is to latch the barrier arm assembly  13 ′ after a set time delay after engaging the barrier arm assembly  13  preventing the exiting through the entrance gate system by holding the barrier arm assembly  13  in an open position. 
     Although  FIG. 1  illustrates two entrance gate systems installed side-by-side, there could be more than two such entrance gate systems. It is also envisaged that such entrance gate systems could also be installed as an exit gate system wherein the outer support column  12 ′, which would then be positioned inwardly of an establishment, may be provided with a detector  100  which detects active security protective devices placed on articles to prevent theft. The support column may also be equipped with an electronic motion detector  101 . In the event that a person passes through the motion detector  101  with the security device disarmed, then the solenoid would be automatically disengaged permitting the person to freely exit the establishment. In the event that the sensing device detects an active security device then this would cause the solenoid  26  to remain engaged preventing the barrier arm assembly  13  to pivot and the alarm would be activated. A by-pass switch can be provided locally or remotely to retract the solenoid latch in the event of false alarms which occur when security devices are not properly deactivated at the cash registry.