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CROSS-REFERENCE TO RELATED APPLICATION 
     This invention claims the benefit of U.S. Provisional Application No. 60/104,061, filed on Oct. 13, 1998. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates generally to handcuff keys, and more specifically to removable handcuff keys used for training personnel in the art of applying handcuffs. 
     2. Background Art 
     Training for police and other security officers requires extensive familiarity with the use of handcuffs in the process of arresting a subject. Because a person being arrested may be belligerent, combative, drunk and/or uncooperative, a trainee must become prepared to handle many different situations in which handcuffs must be placed on a subject&#39;s wrists. The best type of training is considered by most experienced law enforcement instructors to be actual or simulated demonstrations during which “tactical handcuffing” is actually performed by the trainee. Even when a subject is not combative, a trainee must be able to handcuff a subject&#39;s wrists efficiently without causing pain. Such training necessarily involves repeated locking and unlocking the cuffs. A drawback to using a standard handcuff key for training is the amount of time required to locate the key, fit it into the keyhole of each handcuff, and withdrawing the key to a safe location. 
     Accordingly, what is considered necessary is a mechanism usable with standard return standard handcuffs which does not mechanically alter the handcuffs, which further is removable to return to standard street use mode, and which provides for easy, simple and unobstructed handcuff use training. 
     SUMMARY OF THE INVENTION 
     Accordingly, there is provided herein a training handcuff key comprising a shaft, the shaft having a spline, a spline end and a base portion end, and a mounting base which includes at least one magnetized member and a gripping member permitting turning of the key and shaft within a keyhole of a handcuff. The magnetized member preferably retains the key releasably attached to a magnetizable handcuff wall material surrounding the keyhole for training in the use of handcuffs, providing a quick release, locking mechanism for the handcuffs. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 illustrates a set of standard handcuffs including an aperture for receiving a training key according to the present invention. 
     FIG. 2 is a detail view of the keyhole in one of the handcuffs shown in FIG.  1 . 
     FIG. 3 is an elevational view of a handcuff training key according to the present invention. 
     FIG.  4 . is a view of the handcuff training key shown in FIG.  3 . 
     FIG.  5 . is an exploded view of the handcuff key according to the present invention. 
     FIG.  6 . illustrates the use of an alternative embodiment of the handcuff training key according to the invention in a cross-sectional view of the handcuff walls and keyhole. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Handcuffs are standard police and security industry related tools used for restraining, controlling or restricting the movement of unreasonable persons. FIG. 1 illustrates in an elevational view a pair of standard handcuffs  10 , joined to each other by a chain  11 , welded at either end to a shackle base  44  of each handcuff  10 . Handcuffs  10  may also be joined by a hinge (not shown) or other known mechanism. An arcuate, rotatable shackle bracelet  46 , including ratchet teeth  48 , is attached to the shackle base  44  at a protruding end  45  of shackle base  44 . The shackle bracelet  46  is joined to the protruding shackle end  45  at a pivot  50  which permits the shackle bracelet  46  to rotate about the pivot  50  relative to the shackle base  44 . The shackle base  44  includes a flat keyhole surface  43  in which is disposed a keyhole  20 . 
     The ratchet teeth  48  of shackle bracelet  46  are disposed at a distal end  52  of the shackle bracelet  46  and are spaced from the proximate end which attaches the shackle bracelet  46  at pivot  50 . The shackle bracelet end  52  is shaped and dimensioned to be inserted and to slide into an elongated base opening, also referred to as a bail, (not shown in this view), of the shackle base  44 . Insertion of the shackle bracelet end  52  into the bail in a direction that closes the opening defined by the shackle base  44  and shackle bracelet  46  causes the ratchet teeth  48  to engage a one-way pawl (not shown in this view) located within the shackle base  44 . 
     The pawl operates in a conventional manner to engage ratchet teeth  48  so as to inhibit the opening of the handcuffs  10  once they have been used to shackle an object. If the handcuffs  10  are being placed around an object, for example a wrist, successive ratchet teeth  48  are engaged by the pawl until further insertion of the shackle bracelet  46  into the bail is restricted by the restrained object. For some handcuffs, the bail has a construction that permits the shackle bracelet  46  to slide completely through the base  44  and to complete a revolution about the pivot  50  if no object is present to stop the rotation of the shackle bracelet  46 . 
     The ratchet teeth  48 , by engagement with the pawl, restrict the counter-rotation of the shackle bracelet  46  in the opening direction, opposite to that of the closing direction. To release an object which has been shackled by the handcuff  10 , a lock release mechanism disengages the one-way pawl from the ratchet teeth  48 , releasing the shackle bracelet  46  to rotate in the opening direction, thereby expanding the opening between the shackle base  44  and the shackle bracelet  46 . When the last ratchet  48  clears the pawl, the shackle extension  46  is free to rotate about pivot  50 , and opening the bracelet permits removal of the restrained object, e.g., wrist, from the handcuffs  10 . 
     The locking mechanism for release of the pawl includes a standard lock and key mechanism, to which keyhole  20  provides access. The keyhole  20 , shown in a detailed view in FIG. 2, normally comprises a rounded portion  21  for receiving a shaft of a key (not shown in this view) and a slot portion  24  for receiving the key spline, such as spline  14  (FIG.  3 ), which extends radially from the shaft. A spline  14  is normally a flattened key spline attached to one end of the shaft  12  of the key  25  (FIG.  3 ). 
     The detail view of keyhole  20  (FIG. 2) further illustrates a standard orientation pin  22  which is centrally disposed in the keyhole rounded portion  21  and is attached to an inner wall  41  within the shackle base  44 . The pin  22  extends within the base  44  from inner wall  41  outwardly toward the outer surface of the shackle base  44 , but ideally does not extend fully to that surface. The orientation pin  22  is used to position the key  25  so that the spline can properly engage a pawl lever  33  (shown in phantom in FIG. 2) which in turn translates releases the pawl  35  (shown in phantom in FIG.  2 ), so as to release the ratchet teeth. 
     As illustrated in FIG. 3, a training handcuff key  25  according to the present invention comprises a key shaft  12 , a magnet washer  26  and a knob assembly  32 . The key shaft  12  preferably is cylindrical in shape, the cylinder having dimensions permitting its insertion within the keyhole rounded portion  21 . The shaft  12  further comprises a pin end  16 , and a longitudinal bore  18  concentric with the centerline CL extending through the shaft  12  from the pin end  16  toward the base portion end  19 . A flat, thin spline  14  extends radially from the shaft  12  adjacent the pin end  16 . 
     The dimensions of the bore  18  allow the guiding pin  22  located in the keyhole  20  to fit into the hollow bore  18  of the key shaft  12  with sufficient clearance so that the key shaft  12  can rotate about the centerline CL while pin  22  is within bore  18 . The shaft  12  further comprises a base portion end  19 , disposed longitudinally opposite the shaft  12  from the pin end  16 , as will be described in greater detail with reference to FIG.  5 . 
     The key shaft  12 , including appropriate dimensions of bore  18  and spline  14 , is designed to fit the standard locking mechanism in most police issue handcuffs. It will be understood that the key shaft  12  can be modified to fit other locking mechanisms, as well, for non-standard issue handcuffs (not shown). In most respects, the key shaft  12  and spline  14  mirrors the identical items in a standard handcuff key. 
     The knob assembly  32  preferably comprises a mounting base  34  and a gripping section  36 . The mounting base  34  preferably comprises a cylindrical magnetizable member, preferably metal, having a predetermined diameter and circumferential shape. The mounting base  34  is concentric to the shaft  12 , and has a diameter which is significantly larger than that of the rounded portion  21  of keyhole  20 . Although shown as two separate members  34 , 36  in FIGS. 3 and 5, the knob assembly  32  may be constructed as a unit in an alternate embodiment. 
     The gripping section  36  of the knob assembly is preferably constructed to provide a gripping surface disposed along the axial and circumferential directions. Preferably, the shape of the gripping section  36  is of a hexagonal cylinder, similar to a nut, that is concentric to the shaft  12 . The flats  38  gripping section  36  should provide a good gripping surface for fingers of an average hand, and may be knurled or otherwise scored to provide a frictional engagement with a user&#39;s fingers. 
     The diameter of the hexagonal gripping section  36 , as measured between opposite flats  38 , preferably is somewhat larger than that of the mounting base  34 . The shape of the gripping section  36  allows the user to easily grip the knob assembly  32  and turn the knob assembly  32  and shaft  12  in either the clockwise or counterclockwise direction. 
     The gripping section  36  further includes an aperture  37  into which a shaft mounting portion  42  (FIG. 5) of shaft base portion end  19  is attached, preferably by insertion. The shaft  12  is thus securely attached to the gripping section  36  by interference fit between the shaft mounting portion  42  and the aperture  37 , or by gluing, welding or other appropriate attachment mechanism. The gripping section  36  also preferably comprises a magnetizable metal, but this is not a requirement. Alternatively, the gripping section  36 , the mounting base  34  and the shaft are integral and manufactured as a unit, the complete gripping section comprising a magnetizable material, and a magnet washer (not shown) being attached to the shaft at an appropriate position. 
     The magnet washer  26  preferably is a circular disk having two flat sides  28 , 30  and a central aperture  31 . Magnet washer  26  is connected to the key shaft  12  by insertion of key shaft  12  into the aperture  31  in a concentric configuration so that both the flat sides  28 , 30  of the magnet washer  26  are at right angles to the shaft centerline CL. The second flat side  30  of the magnet washer  12  is adjacent the base  34 . The diameter of the magnet washer  26  also must be larger than the diameter of the keyhole aperture  20 , to ensure that only the key shaft  12  can enter the keyhole  20 . In an alternative embodiment, the magnet washer may be a similar disk (not shown) to washer  26  that is cracked or broken at appropriate opposite disposed positions. The broken disk can be attached around the shaft of a key by gluing, the two half disks of the magnet washer also having opposite polarity and thus attracting each other magnetically. 
     In the preferred configuration, the surface  28  of magnet washer  26  is retained perpendicular to the shaft centerline CL, and insertion into the keyhole causes the surface  28  to lay flat against the keyhole surface  43  of the shackle base  44 . Flat engagement of the magnet surface  28  against the flat, smooth surface  43  of the handcuff base  44  releasably and securely attaches the training handcuff key  25  within the keyhole  20 . 
     Referring now to FIGS. 3 and 4, a reference dot  40  is disposed adjacent the edge of the upper surface  39  of the gripping section  36  to facilitate easy removal of the key  25 . The radial location of the reference dot  40  on the surface  39  corresponds to the radial position of the spline  14  on the key shaft  12 . This allows the user to know in which direction the spline  14  is pointing when the key shaft  12  and spline  14  are inserted into a keyhole  20  and the visibility of spline  14  is blocked by wall  43 . 
     The reference dot  40  is preferably a spherical indentation in the upper surface  39  of the gripping section  36 . However, the reference dot  40  can also take the form of grooves, stickers or other marking devices, as appropriate. The indentation of reference dot  40  is preferably deep enough to be felt by the fingertips of a user. 
     Proper use of this invention causes the handcuff key  25  to remain in place within the keyhole  20  even through jarring or violent movements of the training subjects, which are sometimes necessary to simulate actual apprehension situations. The magnetic pull of magnet washer  26  is strong enough to ensure that the device will not be dislodged from the keyhole  20  if the handcuffs  44  are moved around violently or dropped. 
     Rotating the gripping portion  36  causes the key shaft  12  and spline  14  to rotate inside the keyhole  20 . The magnet washer  26  retains the key  25  releasably attached to the base surface  43  by magnetic attraction, since most handcuffs are manufactured from stainless steel. As the key shaft  12  rotates, the spline  14  interacts with the pawl  33  located in the locking mechanism, removing the pawl  35  from engagement with the ratchet teeth (not shown in this view), thereby causing the handcuffs  10  to unlock. The gripping portion  36  can be turned in either clockwise or counterclockwise directions allowing the user to lock and unlock a double lock mechanism, a standard feature of most standard handcuffs. 
     The handcuffs  10  can also be used in their normal, non-training operation as the training keys  25  can be easily removed by aligning the reference dot  40  and the spline  14  with the slot  24  of keyhole  20 . The user can then pull the keys  25  out of the keyholes  20 , thereby removing them. Thereafter, standard handcuff keys may then be used to lock and unlock the handcuffs  10 . The inventive training keys  25  can be re-used in training by reattaching the keys  25  to the handcuffs  10  as described above. 
     An inventive key  25  is constructed by inserting the base portion end  19  of key shaft  12 , including an integral spline  14 , through apertures  31 ,  35 ,  37  in the magnet washer  26 , in the mounting base  34  and in the gripping section  36 , respectively. Care must be taken in the insertion of the shaft into aperture  37  of the gripping section  36  so that the spline  14  is in the same radial position relative to the centerline CL as the reference dot  40 . 
     Referring now to the exploded view of FIG. 5, it can be seen that shaft  12  of key  25  includes a shaft mounting portion  42 , having a shaft diameter that is somewhat smaller than the diameter of shaft  12  adjacent the pin end  16 . The change in diameter provides a shoulder  44  which acts as a stop for the magnet washer  26 . The magnet washer  26  has a central bore  31  into which shaft mounting portion  42  is inserted. The shoulder  44  engages surface  28  of the magnet washer  26  to retain the washer in place. 
     The mounting base  34  also has a central aperture  35  into which shaft mounting portion  42  is also inserted. The gripping section aperture  37  has a diameter exactly at or more preferable slightly smaller than the diameter of shaft mounting portion  42  to provide an interference fit, and to secure the gripping portion  36  onto the shaft mounting portion  42 , thereby retaining the mounting base  34  and magnet washer  26  on the shaft  12 . The axial length of the shaft mounting portion  42  is approximately equal to the combined widths of the magnet washer  26 , the mounting base  34  and the gripping portion  36 , thus ensuring that the shaft mounting portion  42  does not protrude beyond the upper surface  39  of the gripping portion  36 . 
     Referring now to the partial cross-sectional view of FIG. 6, use of an alternative embodiment of the inventive key  25  is illustrated. The pin end  16  of key  25  is inserted into the keyhole  20 , the shaft  12  being aligned with the keyhole rounded portion  21  and the spline  14  clearing the keyhole  20  by means of the slot portion  24 . Perpendicular orientation of the shaft  12  to the surface  43  of the handcuff base  44  causes the shaft bore  18  to fit over the guiding pin  22 . Bore  18  has a dimension which inhibits the spline end  16  of the key shaft  12  from reaching the inner wall surface  41  of the shackle base  44 . The magnet washer  26  has sufficient magnetic attraction to retain the knob assembly  32 , in this embodiment comprising only the gripping portion  36 , adjacent the surface  43  of the shackle base  44 . Thus attached, the key  25  does not fall out of the keyhole  20 , irrespective of the angular position of the key spline  14  within the keyhole or any violent jarring of the handcuffs  10 . 
     Rotation of the gripping section  36  causes angular rotation of the spline  14  around the pin  22 . The dimensions of the spline  14  and the pawl lever  33  are arranged to engage, as shown, when the angular position of the spline  14  is rotated within the walls of the handcuff  10 . Rotating the gripping section  36  in one direction double locks the handcuffs  10 , while rotating in the other direction translates the pawl lever  33  to release the pawl  35  from the ratchet teeth (not shown in FIG.  6 ). 
     Rotation of the training handcuff key  25  provides a similar, if not identical, function to that of a standard handcuff key, and further provides two essential features of the present invention. First, the magnet washer  26  retains the knob assembly  32  against the wall  43  and the key  25  within the keyhole  20  at all times during a training session, including when the handcuffs are dropped or violently jarred. Of course, releasably attaching the key  25  within the keyhole  20  is done without interfering with the function of the spline end of the key  25 , which is free to rotate and lock and unlock the handcuffs at will. 
     A second feature is that the gripping section surface  39  is preferably as close to and as parallel as possible to the surface  43  of the shackle base  44 . Although shown as a flat surface  39 , the outer surface of gripping section  36  may be slightly rounded or otherwise beveled. Thus, the training handcuff key  25  does not interfere with the training of use of the handcuffs  10 , in the manipulation of the handcuffs to restrain a subject or in storage of the handcuffs in a container, e.g., a handcuff holster. 
     However, the handcuff key  25  should be removable from standard issue handcuffs, which permits the same handcuffs to be utilized following their use for training. 
     These and other features which are variants of this invention will become apparent to a person of ordinary skill in the art once a full understanding of the inventive features is achieved. Thus, the preceding description of the preferred embodiments is provided for illustrative purposes only, and not for purposes of limitation, the scope of the invention only being limited by the following claims.

Summary:
A training handcuff key for use during training of security officers in the use of handcuffs used to restrain a subject. The training key includes a magnet washer that holds the key adjacent the surface of the handcuff keyhole, even during violent jerking and/or dropping of the handcuffs during simulated apprehension situations. The training key operates in all respects as does a standard handcuff key, but includes the feature of remaining adjacent the handcuff keyhole, while having a profile which does not interfere with the training use of the handcuffs. The training key is removable after completion of the training exercises, permitting the handcuffs to be used in a standard manner. Use of the training handcuff key dramatically reduces the time required to remove the handcuffs after they have been applied to the subject, therefore allowing the trainer and the trainees more time to develop proper and efficient methods of handcuffing and dramatically improve their skills in proper handcuffing techniques.