Abstract:
An electromechanical lock comprises a housing, a rectilinear locking lever slidable within the housing, a blocking element positioned adjacent the locking lever that is movable between a first position that engages with the locking lever and a second position that disengages with the locking lever, and an actuating device operable to control movement of the blocking element between the first and second positions.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates to an improved electronic lock for securing goods and areas requiring a high degree of security. More particularly, this invention relates to an electronic lock that can be locked and unlocked electronically. 
     2. Description of the Related Art 
     Safes and other secure containers have traditionally used combination locks for controlling and authorizing entry. Conventional locks were mechanical and relied on a person dialing a correct combination on a rotating dial. The rotation positioned mechanical elements within the lock such that dialing the correct combination allowed a locking bolt to release the container door. Proper dial rotation aligned gates in tumblers. Once the gates were aligned, a fence on a fence lever entered the aligned gates. Continued rotation of the dial and tumblers pulled the fence lever and withdrew the bolt. 
     However, over the years electromechanical locks have gradually replaced the mechanical locks described above. Indeed, electromechanical locks themselves have seen many improvements over the years. The use of sophisticated electronic logic circuitry has enabled the implementation of a series of complex and unique electronic combinations which has made improper entry into secured areas more difficult. When the lock is used to secure entry to a container, the electronic components are typically mounted within a housing inside the container door. The housing contains an actuating device and a circuit board. The electronic key pad transmits a signal to the circuit board, which contains the electronic circuitry that allows the lock to open and close. The keypad is located on the outside of the housing so as to be accessible to the user. A cable typically extends between the keypad and the circuit board for transmitting signals between the two components. 
     In addition to the electronic circuitry, electromechanical locks include a bolt. The bolt is movably constructed and is coupled to a bolt-displacing device enabling a user to selectively move the bolt into one of at least two end positions by means of the actuating device. The lock is blocked and therefore “locked” in a first end position of the bolt and unblocked or “open” and “unlocked” in a second end position of the bolt. When the user enters the correct combination into the electronic keypad, a signal is transmitted to the circuit board. The circuit board in turn actuates the actuating device, which allows the locking bolt to move to the unlocked position within the housing, thus allowing the user to open the safe door. 
     There are two types of bolts, rotary bolts and rectilinear bolts. In particular, rectilinear bolt locking devices mount a bolt within a housing for moving between locked and unlocked positions. Thus, instead of pivoting like rotary bolts, linear bolts slide into and out of the locking device housing. When the user enters the correct combination, the lock mechanism releases thus allowing the locking bolt to slide into the housing. 
     Although known electronic safety locks have proven effective in everyday practical use, there is a need for improvement, particularly with regard to design. In known electronic locks, the interaction of the bolt and the blocking member is mechanically quite complex thus requiring complicated and expensive mounting. In addition, most electronic locks require the consumption of a great deal of energy causing frequent replacement of the power source. When the correct combination is entered, a signal is given to an actuator move the locking mechanism into the open position. The actuator causes the locking mechanism to remain open for a period of time after which the signal to re-lock is automatically triggered. Thus, known electronic locks typically require the consumption of excess energy. 
     BRIEF SUMMARY OF THE INVENTION 
     The present invention addresses the foregoing problems by providing an electronic lock which has a simplified mechanical design regarding the interaction of the bolt and blocking member. In addition, the present design does not require the consumption of a great deal of energy and results in a power source that needs to be replaced infrequently. 
     The present invention provides an electromechanical lock that includes a housing, a rectilinear locking lever slidable within the housing, a blocking element positioned adjacent the locking lever that is movable between a first position that engages with the locking lever and a second position that disengages with the locking lever, and an actuating device operable to control movement of the blocking element between the first and second positions. 
     The present invention also provides a method of opening an electromechanical lock that includes the steps of providing an electromechanical lock comprising a housing, a locking lever slidable within the housing, a blocking element movable between a first position that engages with the locking lever and a second position that disengages with the locking lever, and an actuating device operable to control movement of the blocking element, entering a combination into a key pad, transmitting a signal to a circuit board operably coupled to the electromechanical lock indicating the entered combination, operating the actuating device to move the blocking element from the first position to the second position upon entry of a correct combination, and rotating a lock dial to retract the locking lever. 
     Other objects, advantages and capabilities of the present invention will become apparent from the following detailed description, taken in conjunction with the accompanying drawings illustrating one embodiment of the invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       For a better understanding of the invention, and to show how the same may be carried into effect, reference will now be made, by way of example, to the accompanying drawings, in which: 
         FIG. 1A  is a perspective view of an electromechanical lock mounted to a container wall. 
         FIG. 1B  is a perspective view of the electromechanical lock in accordance with an aspect of the invention depicting the locking bolt in the locked position. 
         FIG. 2A  is a top view of the electromechanical lock in accordance with one aspect of the invention depicting the locking bolt in the unlocked position. 
         FIG. 2B  is a top view of the electromechanical lock in accordance with one aspect of the invention with the locking lever removed to show detail and depicting the locking bolt in the unlocked position. 
         FIG. 3A  is a perspective view of one aspect of the locking mechanism of the invention depicted in the locked position. 
         FIG. 3B  is a perspective view of one aspect of the locking mechanism of the invention showing the underside of the locking lever. 
         FIG. 4  is a perspective view of the locking mechanism of the invention providing detail of the locking mechanism in the unlocked position. 
         FIG. 5  is a perspective view of the locking mechanism of the invention showing detail of the blocking element in the locked position. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring now to  FIGS. 1A and 1B , an exemplary embodiment of an electromechanical lock is depicted with  FIG. 1B  depicting the lock in the lock position. Electromechanical lock  10  broadly includes housing  12 , cam  14 , actuating device  16 , locking lever  18 , and blocking element  20 . Locking lever  18  and blocking element  20  together comprise the locking mechanism  19  of the invention. Actuating device  16  may be a rotary motor or like alternatives known to those of ordinary skill in the art. Housing  12  is mounted to wall  22 . Wall  22  is representative of the door of a safe, container or secure room. Shaft  24  operably engages cam  14  and extends through wall  22  where it mates with electronic dial  26 . When a combination is input into electronic dial  26  a signal is transmitted to a circuit board located within the housing which recognizes the combination as correct or incorrect. If the combination is the correct combination, a signal is sent to actuating device  16  via contact points  17 , which in turn causes blocking element  20  to move into the unlocked position or in other words into a position in which the locking lever is no longer “blocked.” This allows the operator to turn dial  26  which in turn causes cam  14  to rotate thereby allowing rectilinear bolt  28  to retract as will be hereinafter be explained in detail. 
       FIG. 2A  is a top view of electromechanical lock  10  in accordance with an embodiment of the invention depicting electromechanical lock  10  in the open position. Referring to  FIGS. 2A and 2B , cam  14  includes first blocking side  30 , second blocking side  32  and projection  33 . Locking lever  18  broadly includes a first cam end  34 , second lock end  36  and intermediate blocking portion  38 . First cam end  34  includes angled side  40 . In the locked position, angled side  40  of first cam end  34  matingly abuts first blocking side  30  of cam  14 . After the correct combination is entered by the operator or user and blocking element  20  moves axially forward (as will be explained in detail below), the operator manually rotates dial  26 . Manual rotation of dial  26  causes shaft  24  to rotate cam  14 . The rotation of cam  14  causes first blocking side  30  to disengage from the angled side  40  of first cam end  34 . As locking lever  18  retracts, second blocking side  32  rotates to matingly abut side facing  42  of locking lever  18  thus allowing locking lever  18  to freely retract into housing  12  as will be explained in additional detail below. 
     First cam end  34  includes tab  44  which is positioned in slot  50  formed by housing  12 . Slot  50  includes first and second blocking side walls  49 ,  51 , respectively. In the locked position ( FIG. 1B ), tab  44  is blocked from further movement by first wall  49  thus preventing locking lever  18  from moving further. In the unlocked position ( FIGS. 2A-2B ), tab  44  abuts second wall  51  and blocks locking lever  18  from retracting further into housing  12 . 
     As best seen in  FIG. 3A , locking lever  18  includes post  46  operably coupled at first cam end  34 . Post  46  extends vertically downward from first cam end  34  and defines post face  47 . As best seen in  FIG. 2B  (with locking lever  18  removed), housing  12  defines a recess  48  into which post  46  is slidingly received. Recess  48  permits post  46  of locking lever  18  to freely slide in housing and retract into the “unlocked” or “open” position as cam  14  is rotated to open electromechanical lock  10 . Cam projection  33  (as best seen in  FIG. 1B ) slidingly abuts generally flat underside  45  of locking lever  18  and engages post  46  at post face  47 . After the correct combination is entered by the operator or user and blocking element  20  moves axially forward into the unblocked position, the operator manually rotates dial  26 . Manual rotation of dial  26  causes shaft  24  to rotate cam  14 . The rotation of cam  14  causes cam projection  33  to engage post  46  at post face  47 . First blocking side  30  disengages from angled side  40  of first cam end  34  to allow retraction of locking lever  18  into housing  12  as cam projection  33  continues to “pull” locking lever  18  into the open position. As locking lever  18  retracts into housing  12 , second blocking side  32  rotates to matingly abut side facing  42  while rounded cam hub  35  of cam  14  matingly engages notched portion  43  of locking lever  18 . Tab  44  engagingly abuts second wall  51  and stops locking lever  18  from retracting further into housing  12 . Locking lever  18  in now retracted into housing  12  and rectilinear lock  28  is now in the open or unlocked position. 
     Referring now to  FIGS. 1 through 4 , second lock end  36  of locking lever  18  includes key element  52  that matingly couples with a key receiving recess  54  defined in rectilinear locking bolt  28 . Those of ordinary skill in the art will appreciate that key element  52  may fixedly couple or detachably couple with key receiving recess  54  of rectilinear locking bolt  28 . For ease of servicing and/or repairing electronic lock  10 , however, those of ordinary skill in the art will appreciate that it is convenient to detachably couple key element  52  with key receiving recess  54 . 
       FIG. 3A  is a perspective view of the locking mechanism  19  of the invention coupled to actuation device  16  showing the locking mechanism  19  in the locked position. Locking mechanism  19  broadly includes locking lever  18  and blocking element  20 . Blocking element  20  includes multiple angled sides and may be hexagonal in shape. Those of ordinary skill in the art will appreciate, however, that blocking mechanism  20  may include any number of angled sides so long as it includes at least one angled side capable of matingly engaging with angled portion  56  of locking lever  18  in the locked position. Top side  60  of blocking element  20  lays matingly adjacent underside  62  of locking lever  18  in the locked position. 
     As best seen in  FIG. 3B , second lock end  36  of locking lever  18  includes angled portion  56  on an underside thereof. Angled portion  56  engagingly abuts a side of blocking element  20  in the locked position. Second lock end  36  may include a generally flat underside portion  58  that allows locking lever  18  to move past blocking element  20  in the unlocked position as will be explained in detail hereinafter. Although portion  56  is illustrated and described as an angled surface, one of ordinary skill in the art will appreciate that any surface configuration that is structured to abut the blocking element and prevent linear sliding movement of the blocking element may be used without departing from the intended scope of the present invention. 
     Blocking element  20  includes first and second internal chambers  64 ,  66  and threaded internal annular ring  68  thereinbetween. Blocking element  20  is coupled to and received on blocking element shaft  70 . Blocking element shaft  70  includes annular threaded projection  72  positioned in between first and second ends  74 ,  76 . First end  74  is operably, rotatably coupled to actuating device  16 . Second end  76  is operably coupled to housing  12  such that actuation by actuating device  16  permits shaft  70  to freely rotate. In the locked position (as best seen in  FIG. 5 ) annular threaded projection  72  is received in first chamber  64  of blocking element  20 . In the unlocked position (as best seen in  FIG. 4 ) annular threaded projection  72  is received in second chamber  66 . Shaft  70  receives first and second springs  78 ,  80 , respectively. 
     Referring now to  FIGS. 1 through 5 , in the unlocked position, second spring  80  biases blocking element  20  toward annular threaded projection  72  such that annular threaded projection  72  contacts but does not engage the threads of internal annular ring  68 . Upon actuation, shaft  70  rotates the threaded annular projection  72  such that it engages the threads of internal annular ring  68  which drives blocking element  20  in a linear manner into first chamber  64  or, as those of ordinary skill in the art will appreciate, into the locked position. In the locked position, first spring  78  is in the “loaded” position while second spring  80  is released. First spring  78  thus biases blocking element  20  toward annular threaded projection  72  such that annular threaded projection  72  contacts but does not engage the threads of internal annular ring  68 . Upon actuation, shaft  70  once again rotates the threaded annular projection  72  such that it engages the threads of internal annular ring  68 , which drives blocking element  20  in a linear manner back into second chamber  66  or, as those of ordinary skill in the art will appreciate, into the unlocked position. Importantly, when the correct combination is entered, a signal is transmitted to the blocking element  20  which causes blocking element  20  to move to the unblocked position. Blocking element  20  remains in the unblocked position until the user rotates dial  26  to move the lock into the locked position. Actuator  16  does not hold blocking element  20  in the unblocked position so that power consumption is reduced. 
     In operation and to open the locked safe door, a user enters a combination into the key pad on dial  26 . A signal is transmitted to a circuit board (not shown) located within housing  12 . If the combination entered is recognized as the correct combination, a signal is sent to actuating device  16  which in turn causes blocking element  20  to move from the locked position to the unlocked position, by the mechanism previously described. The user then turns dial  26  which causes shaft  24  to rotate cam  14  from a first position in which first blocking side  30  blocks angled portion  40  of locking lever  18  to a second position in which second blocking side  32  abuts side facing  42  of locking lever  18 . The user continues to turn dial  26  and locking lever  18  retracts into the open or unlocked position as post  46  slidingly retracts in housing recess  48 . Rectilinear bolt  28  is now in the open position. 
     When a user wants to again lock the safe, the user manually rotates dial  26  which in turn causes shaft  24  to commence rotating cam  14  from the second position to the first position. First blocking side  30  of cam  14  engages angled portion  40  of locking lever and propels it axially forward. The locking lever  18  passes a magnet which activates a switch (not shown) on the circuit board which in turn sends a signal to actuator  16  to move blocking element  20  into the blocked position. Tab  44  slides within slot  50  until tab  44  abuts and engages first side wall  49 . Electronic lock  10  is now in the locked position 
     Although the present invention has been described with reference to exemplary embodiments, workers skilled in the art will recognize that changes may be made in form and detail without departing from the spirit and scope of the invention.