Abstract:
A method and apparatus for locking a security gate operating shaft contained in a security gate operating mechanism having a housing from which extends the operating shaft, which may comprise: a locking collar, having at least one engageable protrusion extending radially, mounted on the operating shaft for rotary motion with it; an operating shaft locking mechanism slide mounting assembly attachable to the housing in one of at least two positions; a locking plate slideably mounted in the slide mounting and having an opening in registration with the operating shaft with at least one locking finger extending into the opening and adapted to engage at least one engageable protrusion; an electrically operated sliding unit adapted, when energized to move the slideable plate to one position against gravity, when deenergized to allow the slideable plate to move with gravity to a second position.

Description:
FIELD OF THE INVENTION  
         [0001]    The present invention relates to the field of automatically controlled security gates and specifically ones which are automatically motor drive in response, e.g., to an approaching vehicle triggering the operation of the gate.  
         BACKGROUND OF THE INVENTION  
         [0002]    Automatically motor driven security gates operated by the approach of, e.g., a vehicle, e.g., with the detection of the presence of the vehicle, or with some coded operating mechanism, e.g., a sound operated or infrared operated coded signaling device are well known in the art. Such gates are very secure and also very convenient, and have the advantage of not having to be personed, i.e., have a gate operator that activates the gate upon the approach of a vehicle authorized to pass through the gage, in ingress or egress. This can also, however, be a disadvantage in the event, e.g., of a power failure. In such cases, especially where the power failure occurs with the gate in an intermediate position between fully open or fully closed, the gate could be desired to be able to be moved from the intermediate position or be desired to be kept in the intermediate position pending the return of power to the gate operating mechanism. A simple and convenient way of accomplishing this goal is needed. The present invention is a way of satisfying that need.  
         SUMMARY OF THE INVENTION  
         [0003]    A method and apparatus for lock a gate operating shaft contained in a security gate operating mechanism having a housing from which extends the operating shaft, is disclosed, which may comprise: a locking collar mounted on the operating shaft for rotary motion along with the operating shaft, and having at least one engageable protrusion extending radially from the locking collar; an operating shaft locking mechanism slide mounting assembly attachable to the housing in one of at least two positions; a locking plate slideably mounted in the slide mounting and having an opening in registration with the operating shaft and having at least one locking finger extending into the opening and adapted to engage the at least one engageable protrusion; an electrically operated sliding unit adapted, when energized, to move the slideable plate to a first position against the force of gravity, and when deenergized to allow the slideable plate to move with the force of gravity to a second position; and, wherein the mounting of the slide mounting assembly in the first position of the slide mounting assembly places the at least one locking finger in a position to engage the at least one engageable protrusion when the electrically operated sliding unit is deenergized and the mounting of the slide mounting assembly in the second position of the slide mounting assembly places the at least one locking finger in a position to engage the at least one engageable protrusion when the electrically operated sliding unit is energized. The at lease one locking finger may comprise a first and a second locking finger, and wherein in the first mounting position of the slide mounting assembly the first locking finger is in the engaging position when the electrically operated sliding unit is deenergized and wherein in the second mounting of the slide mounting assembly the second locking finger is in the engaging position when the electrically operated sliding unit is energized. The locking collar may includes a plurality of engageable protrusions and the electrically operated sliding unit may comprise a solenoid operated arm connected to the locking plate. The locking collar may comprise a sprocket wheel having a plurality of radially extending sprocket teeth. The electrically operated sliding unit may be electrically connected to a power source that is also electrically connected to the source of electrical power for operating the operating shaft and the first mounting position of the slide mounting assembly is a fail-locked position, or the electrically operated sliding unit may be electrically connected to a power source that is also electrically connected to the source of electrical power for operating the operating shaft and the first mounting position of the slide mounting assembly is a fail-locked position. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0004]    [0004]FIG. 1 shows a perspective view of a gate operating mechanism driving member according to an embodiment of the present invention;  
         [0005]    FIGS.  2 ( a ),  2 ( b ),  2 ( c ) and  2 ( d ) show side views of an embodiment of the present invention in several operating positions of the present invention; and,  
         [0006]    [0006]FIG. 3 shows another example of an engaging member according to another embodiment of the present invention. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0007]    Turning now to FIG. 1 there is shown a perspective view of an embodiment of the present invention. This embodiment may include a motorized security gate operating system  10 , in the case of FIG. 1, only a portion of the security gate operating mechanism need be illustrated to exemplify the present invention, e.g., the reduction gear that reduces the speed provided on an input shaft  14  from a drive motor (not shown) to provide on an output shaft  20  a number of RPM of from, e.g., 1 or 2 RPM to 10-20 RPM, depending upon the type of motorized security gate being operated. It will be understood by those in the art that the present invention may be used with, e.g., a chain driven sliding gate system, wherein the gate slides back and forth, e.g., on a track and the drive shaft is, e.g., fitted with a chain drive sprocket. In this event the higher range of RPM may typically be used. Alternatively, e.g., the security gate system may be a swinging gate system, in which event, the output drive shaft may be directly connected to, e.g., one arm of a pivoted arm driving mechanism and the lower range of RPM could be more appropriate.  
         [0008]    The security gate driving mechanism  10  may have a housing  12  which may have a side wall  18 . The side wall  18  may also include an output shaft mounting plate  16  mounted to the housing by mounting nuts  28 . The mounting plate  16  may have a generally circular raised surface  24  surrounding an opening in the mounting plate  16  for the drive shaft  20 .  
         [0009]    The drive shaft  20  may also have a key way groove  22 , as is well known. According to the present invention there may be attached to the drive shaft  20  a locking collar  29 , which may also have a key way groove  26 . The locking collar  29  may be attached for rotary movement with the output drive shaft  20  with a threaded key as is well known, e.g., for connecting a rotating pulley to such an output operating shaft  20 . The locking collar may have a plurality of engageable protrusions  30 . The engageable protrusions may rest essentially flush against the raised surface  24 , or, as illustrated in FIG. 1 may bed further supported and held in position during engagement by posts  32 . The posts  32  will be understood to be possibly mounted on the locking collar  29 , extending, e.g., from the protrusions  30  and engaging holes formed in the raised surface  24 , or, alternatively may be extensions mounted on the upraised surface and extending into holes (not shown) formed in the protrusions  30 .  
         [0010]    Also attached to the housing of the security gate drive mechanism  10  on the side wall  18  may be a locking mechanism slide mounting assembly  40 . The slide mounting assembly  40  may include a slideable plate  42  and a slidable mounting frame  43 . The slideable mounting frame  43  may have a back wall  60 , a pair of side walls  64  and a pair of front flanges  66  extending from each of the respective side walls  64  generally parallel to the plane of the rear wall  60 . Contained in the rear wall  60  may be at least one adjustable mounting slot  62 . The adjustable mounting slot  62  may serve to enable the positioning of the slideable mounting assembly  40  with respect to the position of the output drive shaft  20  as more fully described below. It will be under stood that this function may be performed, as illustrated in FIG. 1, with the slot  62  receiving a bolt member extending outwardly from the drive mechanism side wall  18  or for aligning a bolt with a receiving hole in the side wall  18  or the like, such that the slideable mounting assembly may be selectively placed in, e.g., one of a pair of first and second selectable positions relative to the output operating shaft  20 .  
         [0011]    Mounted within the slideable mounting assembly  40  can be a slideable locking plate  42 . The slideable locking plate  42  may have an opening  44  in general registration with the operating shaft  20 . Extending into the opening  44  in generally the axis of slideable movement of the slideable locking plate  42  within the slideable mounting assembly  40  may be a pair of locking fingers  72 . Attached to the slideable locking plate  42  by means of, e.g., a slotted operating arm  50  and an attachment pin  52  can be an electrically operated sliding mechanism, which as illustrated can be a solenoid  48 . The solenoid  48  may be attached to the back plate  60  of the slideable mounting assembly  40  by a solenoid housing  49 . As shown in FIG. 1, the slideable locking plate may have side walls of its own (not shown in FIG. 1) extending toward the back wall  60  of the slideable mounting assembly  40 , such that the slideable locking plate is in sliding contact with the front flanges  66  of the slideable mounting assembly  40 . In this event, the locking fingers  70 ,  72 , respectively, and as explained in more detail below, may engage the protrusions  30  of the locking collar  29 . Alternatively, as shown in FIGS.  2 ( a )-( d ) the side walls  41  may extend in the opposite direction, such that the slideable locking plate is essentially in sliding contact with the raised surface  24 . In this embodiment, the fingers  70 ,  72 , when in engagement may engage, e.g., the posts  32  as shown in FIG. 1.  
         [0012]    Turning now to FIGS.  2 ( a )- 2 ( d ), there is shown an embodiment of the present invention illustrating the operation of the slideable locking plate  42  according to the present invention. In this embodiment of the present invention the locking collar has been replaces with a locking pulley  80  into the pulley slot of which can be mounted, e.g., as by welding, engaging pins  82 , which can act as the engaging protrusions or the engaging posts as explained above in regard to FIG. 1.  
         [0013]    In operation, the present invention can be utilized in the following manner. The back plate  60  of the slideable mounting assembly  40  frame  43  can be position such that as shown in FIG. 2( a ), with the solenoid  48  deenergized, i.e., disengaged, the slideable locking plate, e.g., under the influence of gravity has moved to a position where the locking finger  72  is positioned to engage the locking pins  82 , shown in FIGS.  2 ( a ) and  2 ( b ), or the engaging protrusions  30  or posts  32 , as explained above in regard to FIG. 1. Alternatively, with the solenoid  48  energized, i.e., engaged, as shown in FIG. 2( b ) for the first selected position of the slideable mounting mechanism  40  frame  43 , neither of the fingers  70 ,  72  is in a position for engaging the locking collar protrusions  30  or posts  32  of FIG. 1, or the engaging pins  82  of FIG. 2( a ) or ( b ). In this first selectable position of the slideable mounting assembly  40 , therefore, the security gate is in a fail locked position. In such an embodiment of the present invention the solenoid  48  and the motor (not shown) for the security gate operating mechanism  10  may be connected to the same electrical power source, such that failure of power to the motor (not shown) results in the security gate locking mechanism  10  being locked in a position by the locking finger  72  preventing further rotation of the operating shaft  20 .  
         [0014]    In a second selected position of the slideable mounting assembly  40  back plate  60  attachment to the housing side wall  18  of the security gate operating mechanism  10  housing  12 , with the solenoid  48  in the deenergized, i.e., disengaged position, the locking fingers may be in essentially the same position as shown in FIG. 2( b ), i.e., neither being in engagement with the locking collar  29  of locking pulley  80 . However, with the solenoid  48  engaged, as illustrated in FIG. 2( d ), the locking finger  70  can be in position to engage the engaging pins  82 , as shown in FIG. 2( d ) or the engaging protrusions  30  or posts  32  as shown in FIG. 1. In this embodiment, the present invention forms a fail unlocked mode. It will also be understood that the motor (not shown) and the solenoid  48  in this embodiment must be on a separate power supply and the solenoid may be activated or energized independently of whether there exists power to the motor, when it may be desired to prevent movement of the security gate by placing the locking finger  70  in the position of FIG. 20 to engage the engaging pins  82  of FIG. 2 or the engaging protrusions  30  or posts  32  of FIG. 1.  
         [0015]    The present invention has been described through an illustrative presently preferred embodiment and should not be limited to the preferred embodiment. Other embodiments of the present invention can be appreciated by those skilled in the art, e.g., the sliding plate can be spring loaded to the deenergized position, and gravity, thus need not be the returning force, leaving, e.g., the sliding plate to have other axes of sliding movement other than vertical. These and other modifications could be made without departing from the scope of the present invention, as reflected in the appended claims.