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[0001]    This is a Continuation-in-Part application of U.S. patent application Ser. No. 10/443,818 filed on May 23, 2003, which is incorporated herein by reference. 
     
    
     
       FIELD OF THE INVENTION  
         [0002]    The invention relates to magnetic cards or keys for operating magnetic locks.  
           [0003]    Such locks are already known and described for example in European Patents EP 0241323, 0024242, 0498465 and U.S. Pat. No. 3,995,460. The present invention relates to coded magnetic cards to operate such locks as described in the applicant&#39;s U.S. Pat. Nos. 3,611,763 and 4,077,242, the latter titled Metal Magnetic Key. Another is U.S. Pat. No. 3,995,460 describing an embodiment with a hole in the card being impaled by a pivoting pin. That pin however impales the card as the card is being inserted and not as the housing is being rotated as is the case in present embodiments to be described in detail herein.  
           [0004]    To operate the prior locks, a coded magnetic card or key is inserted in the lock to unlock the lock and allow a door, gate or other barrier to be opened. Typically, the card must remain in the lock during unlocking but can be removed when the lock is unlocked. An externally exposed slot is provided for the card in a periphery of an exposed rotatable or fixed position body. The body may be, or form part of, a door catch release knob or handle that allows the magnetic card to be slidingly inserted. Without any inserted card, the lock housing with card slot may be free-turning, through 360 degrees. That is, only without an inserted card is the housing free-turning. The card slot may come to rest at a rotational position not convenient for subsequent card insertion. That random position may not be readily adjustable. It is desirable for the slot to be positioned uppermost for most convenient card insertion and easy visibility of the slot. However, when the lock is used externally in a building or in the open, for a gate way, an uppermost slot exposes the inside of the lock to rain, external surface water, debris and dirt so a side or bottom slot position is preferable.  
           [0005]    In certain applications the magnetic card is retained in the lock during unlocking and locking, so it is not necessary to hold the card in place while rotating the lock body; the card being removable by pulling it out of the slot. However, there is sometimes a requirement that the card should not be removed when the locking mechanism is unlocked as it is not to be left in an unlocked mode. Means to adjust the slot position, return it to a selected null position when the card is removed and lock-in the inserted card when the lock is unlocked are disclosed in the parent case to which this application is a Continuation-in-Part.  
           [0006]    If a standard type card containing an aperture to receive a lock-in pin is inserted into the slot of the card lock-in mechanisms described in the parent case and the user slightly releases pressure on it while rotating the housing, the card lock-in pin in the lock will jam against the card in a location other than the location of the pin aperture. This could make an unwanted depression in the card which could prevent the card from being easily withdrawn from the slot and further pressure could damage the card or the mechanism.  
           [0007]    Also when the card is retained in the housing of such a lock, it is desirable to be able to release finger pressure on the inserted card when the housing is first rotated.  
         OBJECT OF THE INVENTION  
         [0008]    It is the object of the present invention to provide a magnetically coded card that overcomes or substantially ameliorates one or more of the above disadvantages.  
         DISCLOSURE OF THE INVENTION  
         [0009]    According to one aspect of the invention there is provided a magnetically coded card for use with the disclosed locks and comprising at least one dimple projecting therefrom and engaging with the slot upon insertion therein and providing resistance against removal from the slot.  
           [0010]    The magnetically coded card typically comprises an aperture through which a card-impaling lock-in pin of the lock can pass when the card is fully inserted within the slot.  
           [0011]    According to another aspect of the invention, there is provided a magnetically coded card for use with a lock having a slot into which the card is inserted to operate the lock, comprising an aperture for impaling by a card lock-in pin of the lock when the lock housing is subsequently rotated.  
           [0012]    The lock would comprise means to hold the card fully inserted prior to rotation of the housing.  
           [0013]    The magnetically coded card might further comprise at least one-dimple projecting therefrom and engaging with the slot upon insertion therein and providing resistance against removal of the card from the slot.  
           [0014]    There is further disclosed herein a magnetically coded card for use with a lock having a slot into which the card is inserted to operate the lock, and an aperture through which a card-impaling lock-in pin or actuator pin of the lock can pass when the card is fully inserted within the slot, the card comprising a magnetic insert between a hard magnetic sheet and a soft non-magnetic sheet, the hard magnetic sheet having a large opening at the card aperture, and the non-magnetic sheet having a smaller opening flared into the card aperture.  
           [0015]    Preferably, the hard magnetic sheet is made of metal.  
           [0016]    There is further disclosed herein a combination comprising, a lock and a magnetically coded card, the lock comprising a slot into which the card is inserted to operate the lock, and a latching button extending into the slot, the card comprising an aperture for impaling by the latching button when the card is fully inserted within the slot, the aperture having openings of different dimension at each side of the card.  
           [0017]    Preferably, the button has a bevelled upper surface to allow the card to pass by the button when force is applied to the card.  
           [0018]    Preferably, the button is made of hardened steel.  
           [0019]    Preferably, the lock further comprises a spring base having a spring leaf extending therefrom and on which the latching button is located.  
           [0020]    Preferably, the lock further comprises a magnetic shield plate, a non-magnetic cover plate, and a spring plate having a hole therethrough and through which the latching button extends, the spring plate biasing the magnetic shield plate into contact with the non-magnetic cover plate to keep the slot closed when there is no card in the slot.  
           [0021]    There is further disclosed herein a combination comprising a lock and a magnetically coded card, the lock comprising a slot into which the card is inserted to operate the lock, and a latching button extending into the slot, the card comprising a magnetic insert between a hard magnetic sheet and a soft non-magnetic sheet, the card having an aperture therethrough, the hard magnetic sheet having a large opening at the aperture, and the non-magnetic sheet having a smaller opening flared into the aperture. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0022]    Preferred locks with which the magnetically coded card can be used, and preferred forms of the card itself will now be described by way of example with reference to the accompanying drawings, wherein:  
         [0023]    [0023]FIG. 1 is a schematic parts-exploded perspective illustration of a magnetic card-operated lock;  
         [0024]    [0024]FIG. 2A is a schematic parts-exploded perspective illustration of parts of the locking mechanism showing the configuration of the weights to position the card slot sideways for a left-handed door;  
         [0025]    [0025]FIG. 2B is a schematic parts-exploded perspective illustration of parts of the locking mechanism showing the configuration of the weights to position the card slot sideways for a right-handed door;  
         [0026]    [0026]FIG. 2C is a schematic parts-exploded perspective illustration of parts of the locking mechanism showing the configuration of the weights to position the card slot upward for a right-handed door;  
         [0027]    [0027]FIG. 2D is a schematic parts-exploded perspective illustration of parts of the locking mechanism showing the configuration of the weights to position the card slot downward for a right-handed door;  
         [0028]    [0028]FIG. 3 is a schematic cross-sectional view of a door handle incorporating a similar magnetic card-operated weighted card slot lock;  
         [0029]    [0029]FIG. 4 is a schematic parts-exploded perspective illustration of one embodiment of a magnetic card-operated lock;  
         [0030]    [0030]FIG. 5 is a schematic end elevational view of the tailpiece engagement parts of the lock of FIG. 4;  
         [0031]    [0031]FIG. 6 is a schematic parts-exploded perspective illustration of means to hold-in the card using the same aperture in the card through which the lock-in pin passes;  
         [0032]    [0032]FIG. 7 is a cross sectional side view of the assembled lock of FIG. 6 as the card is being inserted;  
         [0033]    [0033]FIG. 8 is a similar view to FIG. 7 with the card fully inserted;  
         [0034]    [0034]FIG. 9 is a cross section of a metal-clad card with hole for lock-in pin; and  
         [0035]    [0035]FIG. 10 is a schematic perspective illustration of a spring base from which there extends a spring leaf and latch button forming part of the mechanism depicted in FIGS. 7 and 8. 
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0036]    Referring to the drawings, in FIG. 1 various components of the lock are shown which are not directly relevant to the present invention and so will not be specially mentioned in the description. More relevant, the lock has a cover  10  with a peripheral slot  11  for receiving a magnetic card  51 . The cover  10  and principal components of the lock, including a lock plate  12  and a magnet pin tumbler carrying lock core  13 , are mounted on a friction free bearing  14  to rotate, together with a securing plate  15 , about a common fixed central axis of the lock and a bearing bushing  29 . In order to operate the lock, a correctly magnetically coded card  51  is inserted in the slot  11  and then the cover  10  (and internal mechanism) is rotated through the arc, typically 90° or more, in a manner already well-known. At the same time, a card tailpiece actuator  20  is engaged and is also rotated. It functions in a manner to be described more fully below.  
         [0037]    A null rotational position for the free-turning cover  10  is determined by two semi-circular weights  17  that are fixed by screws  18  to the securing plate  15  in holes  18 ′. In the FIGS. 1 and 2C the null position of the cover  10  is arranged so that the slot  11  is uppermost. However, the securing plate  15  is provided with four screw holes  19 ′ (FIG. 2) so as to be secured in any one of four rotational positions. Thus, the slot  11  can be set to come to rest due to the gravitational force on the weights either at the top as shown, or facing to the left (FIG. 2A), to the right (FIG. 2B) or downwards (FIG. 2D) according to the position of the weights relative to the lock housing  36  (FIG. 2). Thus, as pictured, four null positions for the slot  11  can be chosen. In each case the lock is operated in the same manner as before, that is by inserting a correctly coded magnetic card into the slot  11  to “unlock” the lock, and rotating the cover  10  from the null position. When the card is removed the weights return the slot to the null position. It will be appreciated that it is a simple matter to change the position of the weights at any time if a different null position is required.  
         [0038]    The described lock can also include a card lock-in mechanism (FIG. 1), that includes a fixed body  16 , the lock actuator  20  and a tail piece driver  21  that operates a connected lock set (not shown) to extend and retract a latch and/or bolt so that a door can be opened or secured. The actuator  20  and the tailpiece driver  21  are mechanically coupled by a slot  22  in the rear face of the actuator that receives a flat finger  23  extending from the front face of the tailpiece driver  21 . Mechanical coupling between the slot  22  and the finger  23  is maintained effective even when the actuator moves a limited distance axially away from or towards the tailpiece driver. Both components  20  and  21  are contained within 1 through-hole  33  in the body  16 .  
         [0039]    The actuator  20  has a peripheral spiral groove  24  into which a remote end of a fixed pin  25  in body  16  is located. The pin extends into the hole  33  to engage in the groove  24 . As a result, turning the cover  10  with a correctly coded card fully inserted and the tumbler carrying core  13  depressed, a driver pin  31  in the rear surface of core  13  engages a notch  37  in disc  30  which in turn rotates a flat portion  38  of the actuator  20  inserted into the axis slot of the disc  30 . This rotates the actuator  20  to move-axially through the body  16  towards the card slot  11  due to the fixed pin  25  in spiral groove  24 . A pointed finger  26  on the front of the actuator  20  enters and extends through a hole  50  provided in the inserted card  51  and thereafter prevents the card being pulled out of the slot  11  as the lock is unlocked. The card cannot be removed until the lock is again locked when the above action is reversed. That is, the card and slot is rotated in the opposite direction retracting the finger  26  from the centre hole  50  in the inserted card  51 . Then the actuator  20  is moved, by relative rotation of the groove  24  and the fixed pin  25 , towards the tailpiece driver  21 .  
         [0040]    The slot  22  of tailpiece actuator  20  is axially movable over the flat finger  23  of the tailpiece driver  21 . The formed end of the tailpiece  32  is received within a slot  49  in the rear surface of the driver  21 . The tailpiece  32  can be provided with a number of transverse lines of weakness (not shown) enabling the tailpiece to be snapped into the required length by the lock installer to fit doors of various thickness. The tailpiece  32  rotates upon rotation of the driver  20  to thereby operate a lock (not shown) into which it extends.  
         [0041]    There is a spring  34  and plunger  35  fitted within the body  16  that serves to prevent inadvertent rotational movement of the tailpiece  32  by the end of the plunger  35  pressing on a flat area of groove  39  around the circumference of tailpiece driver  21 . This feature prevents inadvertent locking or unlocking of the connected lock mechanism that might occur prematurely should the tailpiece  32  be allowed to rotate freely.  
         [0042]    Should it be desirable to provide means to leave the lock in the unlocked mode, a coded unlocking card  52  is used. Such an unlocking card is formed with an open slot  53 , extending from a bottom edge of the card to and including the area of the central hole  50  in the card, to straddle the extended finger  26 . Such an unlocking card may be used to unlock the lock and then be removed in the unlocked position because the open slot  53  allows the card to be withdrawn from the slot  11  with the finger  26  extended, leaving the lock in the unlocked mode. The unlocking card must also be used for locking the lock if it has been left unlocked, because a normal card cannot be fully inserted in the slot  11  due to the extended finger  26 . In this case the cover  10  must first be rotated to the position of the card slot when the unlocking card was removed, then the unlocking card  52  can be inserted and the mechanism operated and the lock housing  36  rotated back to the locked mode where the finger  26  is retracted out of the slot  53  in the card. Then the unlocking card is removed.  
         [0043]    The above described unlocking card as well as a second embodiment of the unlocking card is shown in the applicant&#39;s European Patent EP 0024242. A two-piece card  54  is inserted into the unlocked lock seriatim when the finger  26  is extended across card slot  11  then the two pieces are fitted together in the slot  11 . When both sides are joined around the finger  26 , the lock can be actuated and the housing  36  rotated back to the locked mode where the finger  26  is retracted from slot  11  and the card can be removed in one piece.  
         [0044]    [0044]FIGS. 2A to  2 D illustrate how the cylinder code module  36  (comprising parts  10 ,  11  etc) can be biased into a selected orientation by choice of attachment positions of the weighted securing plate  15 . Arrow A in each of the figures indicates the insertion direction of the magnetically coded card into the cylinder code module. That is, the card-insertion slot  11  can face upwardly, downwardly, left or right, or any angle in between. The two pre-tapped holes  40  in the cylinder code module cover  10  receive screws  19  by which the securing plate  15  is mounted thereto. The weights  17  attached to the securing plate  15  will bias the card-insertion slot  11  into the desired null-orientation by gravity. Four of such positions are depicted.  
         [0045]    In FIG. 3, a lock similar to the lock of FIG. 2A-2D is mounted in a cylindrical lock door operating handle  27  having the rotatable cover  10  and slot  11  as before. The cover is oriented to a chosen position by weights in the manner described above. An important feature of the arrangement of FIG. 3 is a central lock spindle adapter  28  that can be provided to fit different lock spindle dimensions. This enables the same handle  27  to be used with different lock mechanisms or for such handles already installed on locks to be replaced with a magnetic card-operated lock/handle. It is particularly important that the slot  11  can be set to any desired rotational null positioning by selective positioning of the weights  17 . As a result, the lock can be provided with a keyed handle mounted on a left side or a right side of a door, and either inside or outside the door. In all positions the slot  11 , can be automatically positioned as desired due to the selective positioning of the securing plate  15  with weights  17 . If slot  11  is positioned either up or down no change is required for either left or right hand mounting as the slot remains in the desired position due to gravity when the handle points either right or left. For mounting with slot to either side, relocation of the securing plate with its attached weights is required. Such a handle lock can also contain a similar card Lock-in Mechanism as previously described.  
         [0046]    In FIGS. 4 and 5 of the accompanying drawings there is depicted schematically an improved card-lock-in device. In this alternative embodiment, the tip end  56  of the card lock-in pin  45  enters the hole  50  in the inserted card  51  before the lock mechanism begins to unlock the attached lock. This is achieved by moving only the card lock-in pin through the hole in the card at the start of rotation of housing assembly  36 . The other components remain aligned in the body of the lock.  
         [0047]    The card-lock-in pin  45  is L-shaped with its short rear end extending 90° radially. The longer part of the card lock-in pin  45  extends through actuator  47  that in turn is positioned for rotation in sleeve  48 . The tailpiece actuator  47  and sleeve  48  are fitted within the longitudinal hole  33  through body  16 . Rather than milling a spiral groove into the surface of the tailpiece actuator as in the embodiment of FIG. 1, there is a spiral slot cut through the wall of the sleeve  48 . The tailpiece actuator  47  extends through the sleeve  48 . The arc of the spiral slot in sleeve  48  only extends around half its circumference and this provides a more positive card lock-in pin movement. There is a spring  34  and plunger  35  that rides in the groove  39  of the tailpiece driver  43  as is the case with the embodiment of FIG. 1, serving to hold it in place and also to provide a detent flat surface to bias the tailpiece actuator to the “locked” position which is the starting point of rotation. There is a retention screw  42  passing radially through the body  16  to secure the sleeve  48  in place through hole  42 ′.  
         [0048]    The tailpiece actuator  47  is slotted on one end with another slot on its side (not shown) to receive a spring  46  and the 90° bent over short end of card lock-in pin  45 . There is an axial hole through the tailpiece actuator into which the longitudinal part of card lock-in pin  45  extends such that its tip  56  may pass through the hole  50  in magnetic card  51 . As the card lock-in pin  45  moves forward such that its tip extends beyond the leading end of tailpiece actuator  38 , the 90° bent over end of card lock-in pin  45  compresses the spring  46 . That is, the spring urges the card lock-in pin  45  back to the starting position when the lock has returned to the locked mode.  
         [0049]    The tailpiece driver  43  has an off-centre finger  44  extending from its front face. As shown in FIG. 5, the back end of the tailpiece actuator  47  has an hourglass shaped slot into which the finger  44  extends. The 90° bent end of the card lock-in pin  45  is also received in this slot. It should be noted that as a result of the configuration of FIG. 5, the tailpiece actuator  47  can rotate before contacting the finger  44  to begin rotation of the tailpiece driver  43  which unlocks the lock, this is termed “lazy cam” action. It allows the tip end  56  of the card lock-in pin  45  to enter hole  50  in card  51  to prevent its removal from card slot  11  as described in detail below.  
         [0050]    The driver pin of the magnet-carrying core is normally positioned in the lower central area of the driver disc  30 . When a correct card is inserted into the code module it moves the magnet-carrying core  13  of the module downwards. The driver pin  31  in the rear of that core moves down into the open slot  37  of the driver disc  30 . Subsequent rotation of the code module  36  and core rotates the driver pin  31  which in turn rotates the driver disc  30 . The square hole in the disc receives the square portion  38  of the tailpiece actuator so it also is rotated. As the tailpiece actuator  47  carries the bent card lock-in pin  45 , the rotation causes the tip  55  of the pin to ride up the spiral slot in the sleeve  48  moving the pin forward into the card slot where it impales the card  51  through hole  50 , preventing its removal. A circlip  58  prevents disc  30  from moving axially into contact with the rear surface of the magnet pin-carrying core  13 , which could jam the mechanism. Reversing the rotation of the code module retracts the card lock-in pin  45  out of the hole  50  in the card and when fully retracted in the “locked” mode of the lock-in device, the card can be removed from the code module slot.  
         [0051]    Although the card  51  is retained in the housing  36  as it is rotated, it is desirable to be able to release pressure on the inserted card when the housing is first rotated. To accomplish this the card  50  has stamped dimples  57  in its surface so that the initial pressure to insert the card will push the dimples fully into the slot  11  of cover  10  and hold the card in the fully inserted position as the housing is rotated. The dimples are pressed past the cover thickness at the card slot so they grip on the inside surface edge of the cover to offer resistance to the removal of the card.  
         [0052]    [0052]FIGS. 6-9 show another method of holding in the inserted card without adding dimples to it.  
         [0053]    In FIGS. 6-9 the card is of the same type as used with the dimples. It consists of an inner insert of a magnetic sheet material between two sheets of metal, the outer side being magnetic stainless steel and the inner side a non-magnetic material such as stainless steel, brass or aluminium. The use of the two different types of materials creates a card that can be encoded only on the non-magnetic side. The opposite side, being magnetic does not pass the magnetic fields of the internal encoded areas. It is a harder material than the opposing side. This non-magnetic side faces the magnetic pin tumblers in the lock. The harder side is usually stamped with an arrow to indicate which side is to be outwards when inserting the card in the slot. Such stamping must be made on the outside metal part before assembly of the card due to the hardness of the material. The non-magnetic side, being softer can be stamped with an individual serial number or other identification after manufacture. These features are important to the operation of the card lock-in mechanism to be described.  
         [0054]    Although the card with dimples is quite practical, it takes more strength of the fingers to push the dimples past the card slot opening and if the same card is used in locks that do not have the card lock-in feature, the same strength is required to insert the card in those locks as well. Therefore an embodiment of a card that can be retained in the slot without the need for dimples is more acceptable in multi-lock systems.  
         [0055]    [0055]FIG. 6 shows such a card and mechanism in partial exploded view. The card  59  has a through-hole  60  with different diameter openings  61  and  62  on either side of card  59  as shown in detail in FIG. 9. The hole  60  accepts the tip end  56  of lock-in pin  45  or pin  26  of actuator  20  when the card is fully inserted into the card slot  11  of lock cover  10 . The non-magnetic side  63  of the card  59  has the entry  61  flared into hole  60  in the card. The opposite side  64  of the card  59  is the harder material and has the larger diameter hole  62  in alignment with the smaller diameter flared hole  61  on the side  63  for a purpose to be described.  
         [0056]    A spring base  67  with extended spring leaf  65  is located in the inside bottom of cover  10 . This part is shown separately in FIG. 10. At the tip end of spring leaf  65  is affixed a hardened steel latching button  66 . The button  66  extends through the hole  69  in the spring plate  68 . The spring plate biases the magnetic steel shield plate  70  into contact with the non-magnetic cover plate  71  to keep the slot  11  closed when there is no inserted card. Plate  70  also serves to attract all the locking pin tumblers  78  in the core  13  into their respective locking holes  79  of the locking plate  12  thus keeping the lock locked when there is no card in the card slot.  
         [0057]    The latching button  66  also passes through hole  75  in shield plate  70  into the card slot area and when there is no inserted card in the card slot  11 , it also enters hole  76  in cover plate  71  and into hole  77  in lock plate  12 . However when card  59  is being inserted into the card slot  11  it pushes back the latching button  66  to the surface of shield plate  70  and when fully inserted in the card slot  11  the latching button  66  passes through the hole  60  in card  59  to retain the card in the fully inserted position in the card slot  11 .  
         [0058]    [0058]FIG. 7 is a cross section side view of the assembled code module showing a card  59  partially inserted with its bottom end touching the latching button  66 . Note that the upper surface of the button is bevelled to allow the card to pass by the button when slight added force is applied to the card.  
         [0059]    [0059]FIG. 8 is a similar cross section with the card  59  fully inserted and the internal magnet-carrying core  13  pushed down to its fully depressed position to unlock the lock. In so doing the coil spring  72  in plunger  73 , used to return the core  13  to locked position, has been fully compressed into the hole  74  in the bottom of the core  13 . To retain the card  59  fully inserted in the lock after the inserting force is removed requires a force greater than that of the compressed spring  72  which is biasing the core  13  back to the locked position. This larger force is supplied by the entry of the latching button  66  into the larger diameter hole  62  in the side  64  of the card  59  when the card is fully inserted into the lock. The contour of the bottom surface of the button  66  is formed to bear on the bottom edge of the hole  62  without allowing the hole to slip off the button, yet allow this slipping to occur when the card is withdrawn from the slot. As the repeated insertion of cards would cause unwanted wear on the button  66  and the hole  62 , both are preferably made of sufficiently hard metal to withstand these actions without appreciable wear. Due to the required size of the latching button  66  the hole  62  is larger in diameter than the hole  61  on the opposite side  63  of the card  59 .  
         [0060]    The hole  61  has been flared in after assembly of the card to accept the tip  56  of the locking pin  45  or the pin  26  of the actuator  20 . As those pins are a smaller diameter than the base of the latching button  66 , a smaller hole  61  can be used. However the tip of the button  66  is sized to enter the smaller diameter hole  61  so it can extend completely through the hole  60  in the card  59 .  
         [0061]    The locking pin tips  56  or  26  could push the latching button  66  out of the hole  60  in card  59 . If it does so the card  59  is still retained in the card slot  11 . Ideally the pin tips should not push the button  66  completely out of the card hole  60 . Partial insertion of the pin tips  56  or  26  into the card hole  60  is sufficient to retain the card in the slot. When the pin tips  56  or  26  are retracted from the card hole  60  the latching button  66  follows to continue to hold the card  59  in the fully inserted position until it is withdrawn from the card slot.  
         [0062]    Thus has been described various types of cards with aperture for entry of a locking pin to retain the card in the card slot when the lock mechanism has been unlocked by rotation of the cover  10 . Also an improved mechanism to hold-in a card prior to and after said rotation of the cover has extended and then retracted a locking pin through the card aperture.  
         [0063]    It should be appreciated that modifications and alterations obvious to those skilled in the art are not to be considered as beyond the scope of the present invention.

Summary:
A magnetically coded card for use with a lock having a slot into which the card is inserted to operate the lock has an aperture through which a card-impaling lock-in pin of the lock can pass when the card is fully inserted within the slot, thus retaining the card in the slot when the lock is unlocked and releasing the card when the lock is again locked. The card can include at least one dimple projecting therefrom and engaging with the slot upon insertion therein and providing resistance against removal of the card from the slot.