Abstract:
A lock device comprises a housing ( 2 ) which includes an opening ( 4 ) and a core ( 10 ) which is rotatably disposed in the opening. A latching element ( 20 ) co-acts between the housing and the core and can be moved between a release position in which the core is rotatable relative to the housing, and a latching position in which rotation of the core relative to the housing is blocked. An electronically controllable actuator ( 30 ) is disposed in the core and is moveable between an opening-registering-position in which the latching element is movable to the release position, and a latching position in which movement of the latching element to said release position is blocked. A returning means ( 50 ) co-acts mechanically with a key in a key way in the core and with the actuator and such as to move the actuator away from the position of the opening to a further latching position in response to the key being drawn out of the keyway. Movement of the latching element to said release position is blocked by the actuator in this further latching position. Because the returning means is rotatable there is obtained a small latching mechanism that is returned mechanically to a latching position upon removal of the key.

Description:
FIELD OF INVENTION 
       [0001]    The present invention relates generally to an electromechanical lock device and then particularly to a lock device in which a latch mechanism is returned mechanically to a latching position by removal of the key. 
       BACKGROUND OF THE INVENTION 
       [0002]    Electromechanical lock devices that include an electrically co-acting or controlled release mechanism for manoeuvring a lock cylinder are known to the art. For example, U.S. Pat. No. 5,839,307 describes an electromechanical cylinder lock that includes outer lock housing and a core which is rotatable in the lock housing and which is controlled by double lock elements, The core includes a plurality of electromechanical lock elements that include slots which receive a side bar in a non-latched position. A magnetic core rotates the electromechanical latching elements to a desired position in relation to the side bar so as to enable the drum to be rotated. 
         [0003]    One drawback with this known lock device is that it does not include mechanical resetting of the latch elements. This means that the latch elements will remain in a non-latching state if the lock is activated during manoeuvring of the lock, thereby detracting from the security of the lock. This can be the result if the key-mounted battery that powers the latching mechanism is removed. 
         [0004]    A cylinder lock of the kind given in the introduction is described in Swedish patent specification SE 9904771-4. This patent specification describes the manner in which a linearly movable finger (see FIG. 1) rotates an actuator under the control of a key-carried code surface. The actuator, in turn, allows, or prevents, movement of a side bar. 
         [0005]    This solution is encumbered with several drawbacks. Firstly, it is relatively space consuming. Secondly, movement of the finger is code-dependent, in other words it is necessary to include a suitable code surface. This solution will not work if the key lacks such a code surface. 
         [0006]    The European patent publication EP 1134335A2 describes a lock device of the type given in the introduction, in which a latching mechanism includes a linearly movable part. Consequently, this solution is also space consuming and code dependent. 
       SUMMARY OF THE PRESENT INVENTION 
       [0007]    An object of the present invention is to provide a lock device of the above kind in which the electrically controlled latch mechanism is automatically returned to a latching or blocking state when they key is removed from the lock cylinder, wherewith the latch mechanism is code-independent and occupies but a small space. 
         [0008]    The invention is based on the insight that rotary movement of a manoeuvring device in the form of a pivotal pin can be converted to actuator movement. 
         [0009]    Accordingly, the invention provides a lock device according to claim  1 . 
         [0010]    One advantage afforded by the inventive lock device is that the latch mechanism is code-independent since the pivotal or rotatable pin can, in principle, be rotated by any part whatsoever of the key inserted into the lock. Another advantage of the inventive lock device is that the latch mechanism only takes up a small amount of space, since the pivotal pin solely undergoes rotational or pivotal movement. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0011]    The invention will now be described by way of example and with reference to the accompanying drawings, in which 
           [0012]      FIG. 1  illustrates a latch mechanism of a lock constructed in accordance with known technology; 
           [0013]      FIG. 2  is a perspective view of a lock device according to the present invention; 
           [0014]      FIGS. 3   a  and  3   b  illustrate in detail a latch mechanism that comprises a side bar, an actuator, a motor and a pivotal pin included in a lock device according to the present invention; 
           [0015]      FIGS. 4   a  and  4   b  illustrate in detail the pivotal pin shown in  FIGS. 3   a  and  3   b;    
           [0016]      FIGS. 5   a  and  5   b  illustrate in detail the actuator shown in  FIGS. 3   a  and  3   b;    
           [0017]      FIGS. 6   a  and  6   b  are views from beneath the core shown in  FIG. 2 , from which manoeuvring of the pivotal pin is evident; 
           [0018]      FIGS. 7   a  and  7   b  are partially cut-away perspective views of the cylinder core shown in  FIG. 2 , the interaction between a key and the pivotal pin being evident from said figures; 
           [0019]      FIG. 8  is a perspective view of the latch mechanism, showing a biasing spring for co-action with the pivotal pin; 
           [0020]      FIGS. 9   a  and  9   b  are sectional views from above that illustrate spring biasing of the pivotal pin; 
           [0021]      FIGS. 10   a - 10   d  are cross-sectional views of the cylinder core in different stages of the electrical release or restoration of the latch mechanism; 
           [0022]      FIGS. 11   a - 11   f  are cross-sectional views corresponding to those shown in  FIGS. 6   a - 6   d , although showing different stages of a mechanical release of the latch mechanism; 
           [0023]      FIG. 12  is a side view of the latch mechanism in the case of an alternative embodiment of the invention; and 
           [0024]      FIGS. 13   a - 13   c  are plan views of the latch mechanism shown in  FIG. 12  in different latching or blocking states. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0025]    There follows a detailed description of preferred embodiments of the invention.  FIG. 1  illustrates known technology which has already been described in the background section of the present specification and will not be discussed further. 
         [0026]      FIG. 2  is an exploded view of a cylinder core, generally referenced  10 , in a lock device constructed in accordance with the invention. The core  10  is structured for placement in a circular-cylindrical opening  4  in a typical cylinder house  2  and the core will therefore have an outer surface which corresponds essentially to the house opening. The core includes a key way  12  which is configured to receive a key  60  (shown in  FIG. 6   a  for instance) in a typical fashion. The core  10  includes a plurality of pin tumbler openings  14  which receive tumbler pins (not shown) in a typical fashion. The manner in which an appropriately profiled key contacts the tumbler pins and places them on a parting line so that the core  10  can be rotated relative to the lock housing is known in the art and will not therefore will be described here in more detail. 
         [0027]    The function or modus operandi of the tumbler pins is ignored throughout the entire description, and it is assumed and an appropriately profiled key has been inserted in the lock. When it is said, for instance, that the core is blocked or latched it is meant that the core is blocked by the electrically controlled latch mechanism. 
         [0028]      FIG. 2  also illustrates a side bar  20  which is spring biased radially outwards by a spring  22  acting on the side bar. The side bar blocks rotation of the core  10  relative to the housing  2  when it makes engagement in a cavity  6  in the opening  4 ; see  FIG. 10   a . The function of the side bar is described in detail in, for instance, Swedish patent application 79067022-4, which is included by reference in the instant application. 
         [0029]    The core also includes a generally cylindrical actuator  30  which can be rotated by means of a motor  40 . The motor is connected to an electronic module  48  by means of two conductors  42   a ,  42   b . These conductors are intended to extend in a groove in the barrel surface of the core. In addition to including a custom-made micro-regulating unit with an associated memory for storing and executing software together with drive circuits for driving the motor  40  etc, the electronic module also includes a key contact  44  in the form of an electrically conductive metal strip which is intended to make mechanical contact with a key inserted in the key channel  12 . This enables the key and the electronic module to exchange electrical energy and data. Thus, a battery powering the motor  40  and the electronic module  48  can be placed either in the lock device or in the key. A damping spring  46  is provided radially inwards of the motor for damping rotation of the motor  40 . 
         [0030]    Rotation of the actuator  30  can also be influenced by a pivotal pin  50  which has a rotational axle that extends generally at right angles to the rotational axis of the actuator. The pivotal pin is disposed in a channel  16  that extends up to the key way  12  (see for instance  FIG. 6   a ) and parallel with the tumbler pin holes  14 . The pivotal pin is spring biased by means of a spring  52  acting on the pin. The function of the pivotal pin spring will be explained below with reference to  FIG. 8  and  FIGS. 9   a  and  9   b.    
         [0031]    The side bar  20 , the actuator  30  and the motor  40  with associated components, such as the damping spring  46 , are disposed in a recess  10   a  in the barrel surface of the core and are held in place by a cover  18 . Correspondingly, the electronic module  48  is disposed in a recess in the barrel surface of the core opposite the recess  10   a.    
         [0032]    The latch mechanism comprising the side bar  20 , the actuator  30 , the motor  40  and the pivotal pin  50  winnow be described in detail with reference to  FIGS. 3   a ,  3   b  and  5   a ,  5   b . The pivotal pin  50  includes a peg  50   a  which is intended to co-act with a key inserted in the keyway  12 , as explained below. The pivotal pin also includes a recess  50   b  which has a surface that is intended for co-action with the bottom surface of a recess  30   b  on the actuator  30 . The pivotal pin also includes a seating  50   c  for the pivotal pin spring  52 . 
         [0033]    The barrel surface of the actuator  30  is generally cylindrical in shape and includes a longitudinally extending recess  30   a  which is intended to accommodate a part of the side bar  20  when the actuator is located in a release position, as will be explained below. The barrel surface of the actuator also includes a recess  30   b  which extends around the midway portion of the actuator through an angle of about 225 degrees, as shown in  FIGS. 5   a  and  5   b . This recess includes a plurality of planar bottom surfaces which are intended for co-action with the bottom surface of the pivotal pin recess  50   b , as will be explained below. The actuator  30  also includes a neck portion  30   c  which is intended for co-action with the damping spring  46  such as to dampen excessive movement of the actuator and to render manipulation of the lock by hammering against the lock difficult to achieve. Finally, the actuator also includes an axially extending hole  30   d  for accommodating a shaft of the motor  40 . 
         [0034]      FIG. 6   a  is a view of the core  10  from beneath with no key  60  inserted, which clearly shows the key way  12 .  FIG. 6   a  also clearly shows that the peg  50   a  of the pivotal pin extends into the key way. As will clearly be seen from  FIG. 6   b , the key inserted in the key way has forced away the peg  50   a  and thereby caused the pivotal pin to rotate or pivot through an angle of about 30 degrees. The interaction between the pivotal pin  50  and the key  60  is clearly evident from the partially cut-away perspective views of  FIGS. 7   a  and  7   b.    
         [0035]    Because the key bit acts on a rotatable or pivotal pin, the mechanical solution is, in principle, independent of the design of the key bit. This means that the solution is not code-dependent but can be used, in principle with any type of key, which is highly beneficial. 
         [0036]    Biasing of the pivotal pin  50  to the position shown in  FIG. 6   a  is achieved with the aid of a pivotal pin spring  52 , as evident from  FIG. 8 . This spring is tensioned between a plug  54  (shown in  FIG. 9   a ) and the spring seating  50   c  on the pivotal pin and strives to move the pin to the position shown in  FIG. 6   a .  FIG. 9   a  is a sectioned view through to the core  10  and shows on a level with the pivotal pin spring an expanded spring  52  which urges the pivotal pin to a starting position.  FIG. 9   b  illustrates the instance when an inserted key has rotated the pivotal pin so as to compress the pivotal pin spring. However, the in-built force of the spring  52  strives to return the pivotal pin to the position shown in  FIG. 9   a , which is allowed when the key is removed from the key way  12 . 
         [0037]    Normal electrical operation of the actuator  30  will be described below with reference to  FIGS. 10   a - d .  FIG. 10   a  shows a starting position in which the actuator has been rotated by the motor  40  through about 90 degrees from the release position, in which the recess  30   a  for accommodating the side bar coincides with the side bar  20  and therewith allows the side bar to be received. The recess  50   b  in the pivotal pin  50  allows this position of the actuator to be achieved when no key is inserted in the key way  12 . The recesses  30   b  and  50   b  in the actuator and the pivotal pin respectively are thus formed so that the pivotal pin will not influence control of the motor. 
         [0038]    As shown in  FIG. 10   a , the side bar is prevented from leaving the cavity  6  in the lock housing and the core is prevented from rotating in the lock housing. 
         [0039]    When a key  60  is inserted into the key way, thereby rotating the pivotal pin so that its recess  50   b  faces towards the actuator (see  FIG. 10   b ), the actuator is able to rotate through 90 degrees to a release position. This rotation has been completed in  FIG. 10   c , from which it will be seen that the recess  30   a  on the actuator  30  is turned directly towards the side bar  20 . 
         [0040]    Finally, it will be seen from  FIG. 10   d  that the side bar  20  has been pressed into the recess  30   a  of the actuator by rotation of the core  10 . This allows rotation of the core  10  in the lock housing  2 . 
         [0041]    When the key  60  is removed from the core, the motor  40  is controlled electrically such as to rotate the actuator  30  to the latching position shown in  FIG. 10   a . However, should the power supply to the motor be cut-off for some reason or other, or should rotation of the actuator be blocked when the key is withdrawn, the actuator will remain in the release position shown in  FIG. 10   d  and thereby lower the security of the lock device. This may be the result of someone removing from the key the battery that powers the electronic module  48  and the motor  40 , or as the result of a mains failure in respect of a conductor-powered lock. In such cases the latch mechanism of the inventive lock device functions to return the actuator mechanically to a latching position, as will now be described with reference to  FIGS. 11   a - f.    
         [0042]      FIG. 11   a  shows a starting position for removal of the key  60  corresponding to the position shown in  FIG. 10   c . As will be evident from  FIG. 11   b , as the key is removed the pivotal pin  50  begins to rotate to its starting position, see for instance  FIG. 6   a . The bottom surface of the pivotal pin recess  50   b  is therewith brought into contact with the bottom surface of the actuator recess  30   b . In turn, this applies a force F to the actuator below its axis of rotation, as shown in  FIG. 11   c . The actuator is therewith caused to rotate such as to turn the actuator from the release position shown in  FIG. 11   a.    
         [0043]    Rotation of the pivotal pin  50  and therewith rotation of the actuator  30 , continues until the pivotal pin has reached its starting position, see  FIGS. 11   d  and  11   e . In this position, the actuator has rotated from its release position through an angle of about 50 degrees; see  FIG. 11   f.    
         [0044]    The combination of a rotatable or pivotal pin and a rotatable actuator for mechanical return of the latch mechanism that is controlled electrically in normal operation provides a code-independent solution that takes up only a small amount of space in the core. 
         [0045]    In the case of an alternative embodiment shown in  FIG. 12  and in  FIGS. 13   a - c  the motor  40  with its rotatable shaft has been replaced with a linearly active motor or solenoid  140 . This linear motor or solenoid is connected to an actuator  130  which is movable in a longitudinal direction. The actuator includes a hole  130   a  which is intended to receive a peg  120   a  on a side bar  120 . In the position shown in  FIG. 13   a  the side bar can be moved towards the actuator, since the peg is in alignment with the hole  130   a.    
         [0046]    A damping spring  146  corresponding to the earlier described spring  46  lies against the shaft that connects motor and actuator. 
         [0047]    A pivotal pin  150  corresponding to the pivotal pin of the first embodiment is adapted to be moved mechanically by the actuator when removing the key from the lock device. The pin  150  thus includes a peg  150   a  or some other element that can be actuated by means of a key inserted into the lock device. The pin  150  is also spring biased with the aid of a spring (not shown). As will be evident from  FIG. 13   b , as the pivotal pin is rotated a surface on the pin presses against the end surface of the actuator, therewith causing the actuator to move linearly in a direction towards the motor; see  FIG. 13   c . The hole  130   a  is therewith moved out of alignment with the peg  120   a  on the side bar and the side bar is therewith prevented from moving inwardly towards the actuator. The actuator  130  thereby has the same function as the rotatable actuator  30  in the embodiment first described. 
         [0048]    Although a lock device according to the present invention has been described with reference to preferred embodiments thereof, a person of average skill in this art will be aware that modifications and variations can be made within the scope of the accompanying claims. For example, although there has been described a motor which is powered by a battery situated in the key, it will be understood that the motor may be powered by a battery situated in the lock or by an external power source that is connected to the lock by means of electrical conductors. 
         [0049]    The actuator has been described and illustrated in a specific form. It will be understood, however, that the actuator may have any desired form provided that it can be moved from a released position ( FIGS. 11   a ,  13   a ) to a latching position ( FIGS. 11   f ,  13   c ) through the agency of a mechanical control as the key is withdrawn from the lock. 
         [0050]    Although only one pivotal pin has been shown in the figures, it will be understood that the lock device may include more than one pin that co-operate with an inserted key and the actuator. 
         [0051]    The electrical manoeuvring of the actuator  30  to its latching position has been described as rotational movement through 90 degrees. It will be understood that this rotation may involve other degrees of movement provided that the recess  30   a  for accommodating the side bar is not located centrally opposite to the side bar. It will also be understood that the same latching position can be utilized with both electrically and mechanically manoeuvred latch mechanisms. 
         [0052]    Although a combination of an electrically controlled latch mechanism and conventional pin tumblers has been illustrated it will be understood that the concept of the invention can also be applied to lock devices that lack other latching means than the electronically controlled latch mechanism described above.