Patent Publication Number: US-2004045798-A1

Title: High security switch

Description:
BACKGROUND OF THE INVENTION  
       [0001] This invention relates generally to switches which are activateable to control access to secured areas. More particularly, this invention relates to key operated switches employed in high security systems.  
       [0002] In devices to which the invention relates, a key operated switch is employed to open or close an electrical switch which sends a signal to a security system. The signal may, for example, allow limited access, prevent access or, depending on additional factors, provide selective access to a secured area. The signal may be high or low and accordingly may be termed a “momentary” transmittal or may have a duration for an extended period of time which may be termed a “maintain” mode. For some related switch devices, there may be multiple switch settings at various angular positions of the key upon rotation. In highly sophisticated security systems capable of a wide variety of security functions, numerous switches may be employed. Each of the switches may require a specific configuration for a given function, location or signal component of the integrated security system.  
       SUMMARY OF THE INVENTION  
       [0003] Briefly stated, the invention in a preferred form is a high security switch which incorporates an efficient system for implementing a momentary and/or maintain switch modes. The high security switch comprises a cam operator which is mounted in fixed rotatable relationship with a plug of a lock cylinder. A pendulum-like arm is pivotably mounted relative to a base for the lock cylinder. A magnet is carried by the arm. A second magnet is mounted in a fixed relationship with respect to the base and alignable with the first magnet upon pivotable movement of the arm to define a first mode, i.e., momentary or maintain mode, which is defined by the relative polarities of the opposed magnets. In the maintain mode, the arm is pivotably maintained in a given angular position under the magnetic attraction of the magnets. In the momentary mode, the magnets repel and the arm pivotably moves from a position wherein the first and second magnets align. The switch may employ magnets to provide a momentary and maintain mode at spaced angular positions upon selective directional rotation of the key. In one embodiment, a pair of electrical switches, each having two states, is mounted to a panel. The arm carries a pin which engages one or the other of the electrical switches to close the switch contacts.  
       [0004] In accordance with the invention, a method is also provided for setting the operate characteristics of a multi-positional switch wherein switch positions are defined by a pair of opposing poles of magnets. The method may also comprise providing an extractor having a magnetic field strength which is greater than that of the magnets, magnetically bonding the extractor to the magnet, removing the bonded magnet from the switch assembly and inserting a magnet having a selective polarity orientation into the assembly. The method step may essentially comprise merely reversing the orientation of the magnet.  
       [0005] An object of the invention is to provide a new and improved switch for a high security system.  
       [0006] Another object of the invention is to provide a new and improved high security switch having an efficient and reliable operation.  
       [0007] A further object of the invention is to provide a new and improved high security switch that does not require a mechanical spring return mechanism or a mechanical spring for indexing at a given switch position.  
       [0008] A yet further object of the invention is to provide a new and improved high security switch which may be custom configured in the field for a wide range of signal functions in a highly efficient and reliable installation process.  
       [0009] Other objects and advantages of the invention will become apparent from the specification and the drawings. 
     
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
     [0010]FIG. 1 is a frontal perspective view of a high security switch in accordance with the present invention;  
     [0011]FIG. 2 is a rear perspective view of the high security switch of FIG. 1 with a rear cover being removed to show additional detail;  
     [0012]FIG. 3 is a rear perspective view of the high security switch of FIG. 1 with a switch module portion and the rear cover being removed to show additional detail;  
     [0013]FIG. 4 is a rear perspective view of the high security switch of FIG. 1 with an operator sub assembly, the switch module portion and the rear cover being removed to show additional detail;  
     [0014]FIG. 5 is a frontal perspective view of an operator arm of the high security switch assembly of FIG. 1;  
     [0015]FIG. 6 is a rear perspective view of a second embodiment of a high security switch in accordance with the present invention;  
     [0016]FIG. 7 is a rear perspective view of the high security switch of FIG. 6 with a rear cover being removed to show additional detail;  
     [0017]FIG. 8 is a rear perspective view of the high security switch of FIG. 6 with the switch module portion and the rear cover being removed to show additional detail;  
     [0018]FIG. 9 is a rear perspective view of the high security switch of FIG. 6 with an operator sub assembly, the switch module portion and the rear cover being removed-to show additional detail; and  
     [0019]FIG. 10 is a frontal perspective view of a second embodiment of an operator arm which is employed in the high security switch assembly of FIG. 6. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
     [0020] With reference to the drawings, wherein like numerals represent like parts throughout the several figures, a high security switch in accordance with the present invention is generally designated by the numeral  10 . The high security switch  10  is preferably employed in conjunction with a high security system for controlling access to a secured area. The high security switch  10  is typically mounted to a wall (not illustrated) and activated by means of a key (not illustrated) for transmitting an electrical signal to the system. Several such switches are typically employed in a given security system. The high security switch  10  is a secure multi-positionable switch that may assume a number of possible switch configurations and may be readily configured and/or reconfigured in the field as required for a given function.  
     [0021] A support frame  20  which is preferably a unitary construction provides the principal support and assembly base for the switch. The frame has a central cavity  21  that receives a lock cylinder  22 . The lock cylinder includes a rotatable plug  24 . The cylinder  22  may be a conventional high security mechanical lock cylinder, which includes pin tumbler stacks (not illustrated).  
     [0022] The plug  24  has a keyway  26  which receives a key (not illustrated). A proper key defines a parting line between the pins and allows the plug to rotate to various angular positions. In accordance with one aspect of the present invention, the lock cylinder and the switch operator do not require a conventional spring return and/or index mechanism for returning the key plug and/or maintaining the plug in any given angular position. The high security switch  10  includes a faceplate  30  which provides a front cover and surrounds the front face of the lock cylinder. A pair of openings  32  and  34  receive fasteners (not illustrated) for securing the faceplate to the wall, doorframe or other structures (none illustrated). The faceplate is also configured to accommodate LED&#39;s  36  and  38  which may be activated to visually indicate the status and/or other operational characteristics of the switch.  
     [0023] With reference to FIG. 4, a cam operator  40  is mounted at the rear of the plug  22  or an extension of the plug and secured by fasteners  42  so that it is disposed in rotatably fixed relationship with the plug. The operator has a rearwardly projecting pin  41 . The support frame  20  includes a bore  44  which receives a projecting shaft  46  of a pendulum-like operator arm  50  (best illustrated in FIG. 5). The operator arm  50  is mounted for pivotal rotation about the shaft  46 . In one embodiment, the operator arm has an opening, the sides of which form shoulders that function as a cam surface  52 . The cam surface  52  is engageable by pin  41  of the cam operator  40  for pivoting the operator arm  50  to perform the switch functions upon rotation of the plug  24 .  
     [0024] The lower end of the operator arm  50  includes a cylindrical boss  56  which extends forwardly and forms an opening  58  for receiving a cylindrical or disk-like magnet  60 . At the opposite location of the operator arm is a rearward projecting pin or finger  62 .  
     [0025] With reference to FIG. 4, the frame  20  also includes cylindrical bores  64 ,  65  and  66  which are positioned along an arcuate path alignable with the arcuate path of the magnet  60  as the arm  50  pivots. Cylindrical or disk-like magnets  70 ,  72  and  74  are respectively inserted into the bores. The magnets  70 ,  72  and  74  have opposite magnetic polaries at the opposite ends thereof and preferably are similar or identical to magnet  60 . A pair of integral stops  67  and  69  of the frame  20  project rearward to limit the pivot angle of the operator arm  50 .  
     [0026] With reference to FIG. 2, a switch panel  80  is mounted at the rear behind the operator arm  50 . The switch panel  80  integrally mounts an inverted V-shaped boss  82  which defines a cross slot  83  that also extends through the panel  80 . A pair of switches  84  and  86  are mounted above each side of the boss  82 . The switches  84  and  86  include respective actuators or electrical contacts  85  and  87 , which upon engagement from the underside by the operator arm pin or finger  62 , activate the switch by engaging the contacts  85  and  87  and provide for the transmission of an electrical signal. It will thus be seen that upon rotation of the key, the cam operator  40  pivots the operator arm  50  Which carries the pin  62  to engage and close the electrical contacts of switch  84  or  86  depending upon the direction of rotation of the key plug.  
     [0027] With reference to FIG. 6, fasteners  88  extend through the back cover plate  90  which thread through spaced threaded bores  76  of the frame to secure the various components in the proper position.  
     [0028] The position of the operator arm  50  and the resultant signal mode of the switches  84  and  86  is determined by the magnet  60  and the interaction with magnets  70 ,  72  and  74 . Each of the magnets functions as a bar magnet with opposite magnetic poles at opposite ends. Orientation of the magnetic poles determines the specific signal configuration for the switch. In one embodiment of the invention, magnet  60  has a North Pole adjacent the path of the operator arm  50 . Magnet  70  has a South Pole adjacent the interface with the operator arm. Accordingly, magnet  72  has a North Pole and magnet  74  has a South Pole adjacent the path of the operator arm. It should be appreciated that the foregoing magnet relationships provide a switch wherein in the stable non-activated key mode neither switch  84  or  86  is activated. In the key cylinder position without insertion of the key or rotation of the key, the operator arm has the essentially null position illustrated in the drawings, and magnet  60  and magnet  70  attract each other to define a stable null position.  
     [0029] When the key plug and the operator arm are rotated so that magnets  60  and  72  essentially align, because of the different adjacent polarities, the magnets essentially function to attract each other so that the switch  84  is only momentarily tripped and a “momentary” signal is transmitted. The repelling force of the magnets urges the operator arm and the switch to return to the stable null position. When the operator arm is pivoted in the opposite direction because the poles are configured with opposite adjacent polarities between magnet  62  and magnet  74 , there is an attraction between the operator arm at that position and the closed position of the switch is “maintained” until the switch is physically returned by rotation of the key to the null position. Accordingly, it should be appreciated that a “momentary” or “maintain” switch configuration can relatively easily be implemented by the custom pole configuration of the various magnets.  
     [0030] With reference to FIGS. 6 through 10, a second embodiment of a key switch is generally designated by the numeral  110 . As best illustrated in FIG. 7, the switches  84  and  86  are mounted to a switch panel  180  so that they are configured in an opposing oblique configuration. A switch pin  162  extends transversely through an arcuate slot  181  (partially illustrated) of the switch panel  180  and is engageable upon angular movement through the slot against contacts  85  or  87  switches  84  or  86  to open or close the switches. Operator arm  150  (FIGS. 8 and 10) has a slightly different configuration than operator arm  50 . The switch pin  162  is fixedly mounted to extend transversely from the rear side of the operator arm. The cam operator  140 , which may be conventional, is rotatably fixed to the plug  24  or an extension of a plug. In this embodiment, the cam operator  140  engages the cylindrical boss  156  of the operator arm to pivot the operator arm  150  and thereby selectively move the switch pin  162 . Otherwise, the operator arm  150  and high security switch  110  function in substantially the same manner previously described for the operation of operator arm  50  and high security switch  10 .  
     [0031] The switch modes can be selectively determined by the proper setting and/or orientation of the poles of the magnets. The magnets can be removed by means of a strong magnet. For instance, if it is desired to change the polarity of magnet  72 , a strong magnet is placed so that its opposite pole is adjacent to the end of the magnet. The strong magnet functions as an extractor and is pulled to remove the magnet from the bore. A new magnet having an opposite end polarity can be inserted into the bore. For example, the switch position can be changed from a “momentary” to a “maintain” switch position. Alternatively, the magnet may be reversed from end-to-end and reinserted thereby reversing the signal mode. It should be appreciated that each of the magnets may be accordingly custom selected according to a given required signal mode configuration for a given application. Of course, it will likewise be appreciated that the switches  84  or  86  may be oppositely configured so that activation of the electrical switch can transform to on (high) or off (low) as desired.  
     [0032] While preferred embodiments of the foregoing invention have been set for purposes of illustration, the foregoing description should not be deemed a limitation of the invention herein. Accordingly, various modifications, adaptations and alternatives may occur to one skilled in the art without departing from the spirit and the scope of the present invention.