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BACKGROUND OF THE INVENTION 
   The present invention relates to restraints for controlling the movements of detainees and, more particularly, to a restraint system and buckle. 
   Handcuffs are commonly used by law enforcement organizations to restrain detainees who have been taken into custody. However, handcuffs are typically made of metal, and they can injure a detainee&#39;s wrists or arms as they are processed through the law enforcement system. Also, simple handcuffs do not prevent the detainee from moving his hands and arms in ways that could harm other personnel or aid in his escape. Accordingly, systems have been used that allow the handcuffs to be secured to a belt, or other apparel, that is worn by the detainee. However, it is desirable to allow a detainee some controlled arm or hand movement for some purposes like signing forms and using the lavatory. 
   SUMMARY OF THE INVENTION 
   Because the preferred embodiment of the present invention conforms to the human bone, it gives added security, and can be used to effectively and more comfortably restrain the limbs of a detainee than metal handcuffs, which cause metal to come into contact with and chafe the detainee&#39;s skin and bear against the bones of the detainee&#39;s limbs. The preferred embodiment can be adjusted easily to fit large and small individuals, and is effective for courtroom appearances by the detainee. Additionally, the wrist restraints of the preferred wrist restraint system provided by the present allow adjustment of the position of the hands to permit the detainee to accomplish various necessary tasks, while the wrists of the detainee remain restrained by the wrist restraints. Adjustment of the wrist restraints includes adjusting the position of the restraints on the waist belt of the preferred embodiment and 360° rotation of the wrist restraints. Additionally, a single standard handcuff key can be used to lock and unlock the preferred embodiment. The straps of the preferred embodiment cannot be moved to tighten or loosen the ankle and wrist restraints when a buckle associated with a strap is locked. Retention of the strap is not dependent on clamping the belt, and, thus, the preferred fastener eliminates the eccentrics, cams and interference mechanisms of known fasteners for holding straps. Additionally, the straps of the preferred embodiment can be adjusted to restrain the area of a detainee&#39;s arm anywhere from the wrist to the upper arm area. The preferred fastener eliminates the double locking procedure that is necessary in most known metallic handcuffs. The preferred restraint system is also more humane in appearance in that it eliminates chains and metallic handcuffs, and it can be more easily concealed than chains and cuffs. The preferred embodiment of the restraint system can be fitted to a restraint board or a bed, and can be used for ambulatory restraints. 
   The lockable fastener provided by the present invention does not require holes to be punched in the straps that are mounted on the fasteners, but rather define a tortuous path that traps the strap and prevents its adjustment. Further, the locking mechanism of the preferred fastener is enclosed in a housing for added security. The use of 4 rivets to attach the locking mechanism to the inside of the housing of the preferred fastener provides additional security. Also, the preferred fastener includes two independent locking bars on each side of the housing to increase security. If one bar is compromised, the other bar remains engaged. These locking bars are protected from tampering when the preferred fastener is closed and locked. 
   The present invention provides a restraint system including an anchor that can be mounted to the torso of a person, a first lockable fastener operatively associated with the anchor adapted to be locked to mount the anchor to and prevent removal of the anchor from a person, and unlocked to remove the anchor from a person, a pair of wrist restraints, and a second lockable fastener operatively associated with each wrist restraint to rotatably mount the wrist constraint to the anchor. Preferably, the anchor is a waist belt, the first lockable fastener is a lockable buckle, and each wrist restraint is a strap. Also preferably, each second lockable fastener includes a buckle unit, each buckle unit including a pair of buckles that are mounted to each other for rotational movement relative to each other, the buckle unit being adapted to be locked to mount the wrist restraint to and prevent removal of the wrist restraint from the wrist of a person, and unlocked to remove the wrist restraint from the wrist of a person. 
   The present invention also provides a limb restraint system including a strap and a pair of lockable buckles that are used to form the straps into a pair of limb restraints, each of the buckles being adapted to be locked to mount a limb restraint to and prevent removal of a limb restraint from the limb of a person, and unlocked to remove a limb restraint from the limb of a person. 
   The present invention also provides a lockable belt fastener including a housing that can be moved between open and closed positions, the housing being adapted to receive a strap when the housing in the open position and a lock for selectively locking the housing in the closed position and unlocking the housing to permit moving the housing from the closed position to the open position. The housing defines a tortuous path when said housing is closed, and traps a strap within the tortuous path when the housing has received a strap and the housing is closed and locked; the strap being prevented from sliding with respect to the housing when the strap is trapped within the housing. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The following description of the preferred embodiments may be understood better if reference is made to the appended drawing, in which: 
       FIG. 1  is a perspective view of restraint systems provided by the present invention installed on the legs and wrists of a detainee; 
       FIG. 2  is a perspective view of the wrist restraint system shown in  FIG. 1 ; 
       FIG. 3  is a perspective view of the ankle restraint system shown in  FIG. 1 ; 
       FIG. 3A  is a rear view of the system shown in  FIG. 3 ; 
       FIG. 4A  is a top plan view of a buckle provided by the present invention installed on a strap of the type used in the system show in  FIG. 1 ; 
       FIG. 4B  is a side sectional view of the buckle and strap shown in  FIG. 4A  with the buckle in the unlocked and open position; 
       FIG. 4C  is a side sectional view of the buckle and strap shown in  FIG. 4A  with the buckle in the closed and locked position; 
       FIG. 5A  is a top plan view of the buckle shown in  FIG. 4A ; 
       FIG. 5B  is a side view of the buckle shown in  FIG. 5A  installed on a strap; 
       FIG. 6A  is a side view of the locking mechanism of the buckle shown in  FIG. 4A , with the locking elements in the extended, locking position; 
       FIG. 6B  is a top plan view of the locking mechanism shown in  FIG. 6A ; 
       FIG. 7A  is a side view of the locking mechanism shown in  FIG. 6A , with the locking elements in the retracted, unlocked position; 
       FIG. 7B  is a top plan view of the locking mechanism shown in  FIG. 7A ; 
       FIG. 8  is a side sectional view of the locking assembly of the buckle shown in  FIG. 4A ; 
       FIG. 9  is an exploded perspective view of the buckle shown in  FIG. 4A ; 
       FIG. 10  is a top plan view of a section of a strap of the systems shown in  FIGS. 1 and 2 ; and, 
       FIG. 10A  is a sectional view of the strap shown in  FIG. 10  taken along the line  10 A— 10 A. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
   While preferred embodiments of the present invention have been illustrated and described herein, it is to be understood that various changes may be made therein without departing from the spirit of the invention, as defined by the scope of the appended claims. 
     FIG. 1  shows a pair of restraint systems  10  and  12  that are provided by the present invention. Wrist restraint system  10  is used to restrain the arms and hands of a detainee, while ankle restraint system  12  is used to restrain the legs and feet of a detainee. Systems  10  and  12  use locking buckles  14 ,  16  and  18 , which also are provided by the present invention. Buckles  14 ,  16  and  18  can be locked and unlocked using a conventional handcuff key, as is described in more detail below to close and open the buckles and adjust systems  10  and  12  or install them on a detainee. 
     FIG. 2  shows wrist restraint system  10 , which includes a pair of buckles  14 , a pair of buckles  16 , a buckle  18 , and straps  20 ,  22  and  24 . Straps  20 ,  22  and  24  can be any suitable, known, commonly available straps. The components of buckles  14 ,  16  and  18  can be formed of any suitable stainless steel. Strap  20  can be tightened around the waist of a detainee using a buckle  18  by adjusting the size of the loop that is formed by strap  20  when buckle  18  is open. After tightening strap  20  around the detainee&#39;s waist, buckle  18  can be closed and locked to secure strap  20  tightly around the detainee&#39;s waist. Similarly, a buckle  16  is used to form strap  22  into a loop and tighten the loop around the left wrist of the detainee and a second buckle  16  is used to form strap  24  into a loop and tighten the loop around the right wrist of the detainee. Waist strap  20  is passed through a pair of buckles  14  when they are open. Each top buckle  16  is mounted to a bottom buckle  14 , to form a buckle unit  15 , in such a way that buckle  16  can pivot with respect to buckle  14 . Buckles  14  can be slid along belt  20  to the positions on belt  20  at which it is desired to secure the detainee&#39;s hands, and buckles  14  can then be closed and locked to secure buckle units  15  to belt  20  and secure the detainee&#39;s hands to the detainee&#39;s waist area. Therefore, the hands of the detainee remain restrained to belt  20 , but they can be rotated to facilitate accomplishing various tasks that the detainee typically needs to perform while being processed by a law enforcement organization. 
     FIG. 3  shows ankle restraint system  12 , which includes a pair of buckles  18  and a strap  26 . Buckles  18  are used to form two loops  28  and  30  in strap  26 . Loop  28  can be tightened around the detainee&#39;s right ankle using a buckle  18  by adjusting the size of loop  28  when buckle  18  is open and then closing and locking buckle  18  after loop  28  has been tightened around the detainee&#39;s ankle. Similarly, loop  30  can be tightened around the detainee&#39;s left ankle using a second buckle  18  by adjusting the size of loop  30  when buckle  18  is open and then closing and locking buckle  18  after loop  28  has been tightened around the detainee&#39;s ankle. 
   Straps  20 ,  22 ,  24  and  26  can be constructed of KEVLAR®, nylon, polyester or any other suitable strapping material. As shown in  FIGS. 10 and 10A , a steel cable  159  coated with nylon  161  is embedded in each strap  20 ,  22 ,  24  and  26 . Cable  159  makes it difficult for the wearer of systems  10  and  12  to cut straps  10 ,  22 ,  24  or  26  to remove all or part of systems  10  or  12  from the wearer&#39;s body. 
     FIGS. 4 through 9  show the construction of buckles  14 ,  16  and  18 . Buckle  16  includes an upper base  32  and a lower base  34  that form a housing  36  in which the lock assembly  106  for buckle  16  is mounted. Upper base  32  defines a flat section  38 , which defines a key opening  156 , and a pair of sections  40  and  42  that depend from section  38 . Lower base  34  defines a flat section  44  and a pair of sections  46  and  48  that depend from section  44 . Lower base  34  also includes a belt wall  152  and support bar  153  that are used to fix a strap in place. Support bar  153  is riveted to upper housing  32  using rivets  155  and  157 . Belt wall  152  can be formed from a section of section  44  that is cut and then bent upward, which also forms an opening  158 . A pair of strap guides  160  and  162  are defined by or formed on walls  46  and  48 , respectively. Straps inserted through housing  36  should be passed between guides  160  and  162  and section  44  of base  34 . Base  34  also defines holes  166  and  168 . Base bars  200  are provided, each of which defines holes  202  and  204  (see FIG.  9 ), that are used to rivet straps to the base  34 . A strap is riveted to a buckle in system  10  by installing rivets  204  and  206  (see  FIG. 9 ) through holes  202  and  204  in bar  200 , the end of the strap, and holes  168  (as in  FIG. 9 ) or holes  166 . A hinge rivet  50  connects section  42  of upper base  32  to section  48  of lower base  34  through hole  52  formed in section  42  and hole  54  formed in section  48 . A hinge rivet  56  connects section  40  of upper base  32  to section  46  of lower base  34  through hole  58  formed in section  40  and hole  60  formed in section  46 . Thus, upper base  32  can pivot around rivets  50  and  56  with respect to lower base  34  to move buckle  16  between its open position and its closed and locked position, which is shown in  FIGS. 4C and 5B . Buckles  14 ,  16  and  18  are identical with the exceptions that section  38  of buckle  14  defines a hole  178  and section  44  of buckle  16  defines a hole  180 . A rivet  176  is mounted through holes  178  and  180  in such a manner that bases  32  and  34  can pivot with respect to each other. 
   Buckles  14  and  16  are secured to each other for full pivotal movement using a hinge rivet  176 , which is inserted and installed through hole  178  in upper base  32  and hole  180  in lower base  34 . 
   Wrist restraint system  10  is formed from a buckle  18  and a pair of buckle units  15 . Generally, one end of belt  20  is riveted to the lower base  34  of a buckle  18  through holes  168 , and the remaining end, or free end, of belt  20  is looped back through buckle  18 . Similarly, one end of strap  22  is riveted to the lower base  34  of a buckle  16  and the remaining, or free end, of strap  22  is looped back through buckle  16 . One end of strap  24  is riveted to the lower base  34  of a second buckle  16  and the remaining, or free end, of strap  24  is looped back through that buckle  16 . 
     FIGS. 6 and 7  show the locking mechanism  62  of buckles  14 ,  16  and  18 , which is mounted to the undersurface  70  of upper base  32 .  FIG. 6  shows locking mechanism  62  in the locking position, and  FIG. 7  shows locking mechanism  62  in the unlock position. Locking mechanism  62  includes a pair of lock elements  64  and  66 . When buckle  16  is in the closed and locked position, elements  64  and  66  are in their extended positions shown in  FIG. 6 , in which position they extend into openings  68  formed in sides  46  and  48  of lower base  34 . When elements  64  extend into openings  68 , upper base  32  cannot be rotated with respect to lower base  34 , and buckle  16  is locked. When elements  64  and  66  are retracted from within openings  68 , upper base  32  is free to rotate with respect to lower base  34 . Each of elements  64  and  66  defines a pin  74 , which extend from each of the inboard ends  76  and  78  of elements  64  and  66 , respectively. A compression spring  72  is friction fit onto pins  76  and  78 , and biases elements  64  and  66  toward their extended positions. Downwardly extending studs  80  and  82  are friction fit into holes  84  and  86 , respectively, formed in elements  64  and  66 , respectively. Ends  88  and  90  of elements  64  and  66 , respectively, are formed at an angle of approximately 50° to the longitudinal axes of elements  64  and  66  to facilitate entry of ends  88  and  90  into openings  68 . 
   A lock pivot  92  is provided to move elements  64  and  66  between their extended and retracted positions. Pivot  92  defines a pair of cam slots  94  and  96 , and is mounted for pivotal movement in lock mechanism  62 . Lock pivot  92  also defines a key opening  98 , into which the end of a handcuff key fits. With the end of the handcuff key  63  inserted in into key opening  98 , cam pivot  92  can be rotated between the locked position shown in FIG.  6  and the unlock position shown in FIG.  7 . As lock pivot  92  is rotated from the locking position toward the unlock position, the interior surfaces of cam slots  94  and  96  begin to pull pins  80  and  82  toward each other to move elements  64  and  66  toward the unlocking position. A key return spring  104 , which is located on lock pivot  92 , biases lock pivot toward its locking position. 
   Lock assembly  106  is shown in  FIG. 8 , and includes locking mechanism  62 . Assembly  106  includes a stud plate  108 , which defines a hole  110 . Stud  112  defines a post  114  that is mounted within hole  110  of plate  108  in any suitable manner to mount stud  112  to plate  108 . The hollow end of the handcuff key receives stud  112  when the key is inserted into opening  98  of lock pivot  92  during the process of locking and unlocking buckle  16 . Lock pivot  92  defines a hole  100 , which receives a pin  102  defined by key return spring  104 , and stud plate  108  defines a hole  120 , which receives a second pin  118 . Thus, key return spring  104  is mounted between stud plate  108  and lock pivot  92 . Therefore, when lock pivot  92  is rotated by the handcuff key  63  to the unlock position, pins  102  and  118  move closer together, which causes spring  104  to develop a force that rotates lock pivot  92  back to its locking position when the force exerted by the key on lock pivot  92  is released during removal of the key  63  from buckle  16 . A spring plate  116  is located on the upper surface of stud plate  108 . Plate  116  defines a hole  122  through which spring  104  can rest on plate  108 . A cam plate  124  is located on spring plate  116 , and defines an opening  126 , through which lock pivot  92  rests on spring plate  116 . Plate  124  maintains the position of lock pivot  92 . A right slide plate  128  and a left slide plate  130  are located on cam plate  124  and lock pivot  92 . Plates  128  and  130  maintain the positions of elements  64  and  66 . Left slide plate  130  defines a détente  142  that allows passage of the handcuff key  63  as it enters locking assembly  106 . A spacer plate  132  is located on slide plates  128  and  130  and elements  64  and  66 . Spacer plate  132  is provided to ensure proper clearance for elements  64  and  66  and for compression spring  78 . A top plate  138  provides the upper enclosure for lock assembly  106 . Plate  138  is located on spacer  132 . Spacer  132  defines an opening  136  and top plate  138  defines a similar opening  140  that permits the handcuff key  63  to be inserted into locking assembly  106 . Thus, the hollow end of the handcuff key  63  is inserted into locking assembly  106  through opening  140  of top plate  138 , opening  136  of spacer  132 , détente  142  of left slide plate  130 , and opening  98  of lock pivot  92  until it is fully seated on key base  144  of stud  112 . 
   The elements of lock assembly  106  are held together and mounted to the undersurface  70  of upper base  32  by four rivets  146  which pass through openings formed in various of the elements of lock assembly  106 . Specifically, each of top plate  138 , spacer  132 , left slide plate  130 , right slide plate  128 , cam plate  124 , spring plate  116 , and stud plate  108  define identical rivet holes  148  which are aligned with each other when elements  138 ,  132 ,  130 ,  128   124 ,  116  and  108  are aligned properly. Therefore, lock assembly  106  is mounted to surface  70  of upper base  32  by installing rivets into upper base  32  through holes  148 . 
     FIG. 9  illustrates the manner in which straps  20 ,  22  and  24  are mounted to buckles  16  and  18 . Buckle  18  is unlocked and opened, and one end  150  of the strap is riveted to section  44  of base  34  using rivets  206  and  208  and bar  200 . Strap  26  is riveted to section  44  of each buckle  18  of ankle restraint system  12  through all four holes  166  and  168  formed in section  44 . Care must be taken to ensure that the strap lays flat against section  44  and belt wall  152  and support bar  153 , as is shown in FIG.  4 C. 
   The manner of securing the free (un-riveted) end of a strap using a buckle and adjusting the strap around the waist, wrist or ankle of a detainee will be described with reference to waist belt  20  and a buckle  18 . The procedure is the same with respect to all the straps and buckles of systems  10  and  12 . Buckle  18  is unlocked, and upper base  32  is rotated with respect to lower base  34  until buckle  18  is open far enough that end  150  of belt  20  can be inserted into buckle  18  through the space between lower base  34  and the bottom stud plate  108  of lock assembly  106 . Belt  20  is pulled through buckle  18  until it is secured tightly around the waist of the detainee. Upper base  32  is then rotated toward lower base  34  until elements  64  and  66  are forced against sides  46  and  48  of lower base  34 . As movement of upper base  32  toward lower base  34  continues, the beveled construction of ends  88  and  90  of elements  64  and  66 , respectively, cause elements  64  and  66  to move toward each other against the force of spring  78  until ends  88  and  90  reach openings  68  in walls  46  and  48  of lower base  34 , at which point spring  78  moves elements  64  and  66  away from each other until ends  88  and  90  enter openings  68 , and locking mechanism  62  reaches its locking position, and buckle  18  is locked. Belt wall  152 , support bar  153  and edge  154  of lock assembly  106  trap belt  20  in place by creating a tortuous path for belt  20 . In this position, belt  20  is trapped, and cannot be slid with respect to buckle  18  in either direction. To unlock buckle  18 , the handcuff key is inserted through key opening  156 , the hollow end of the key is fit over stud  112 , and, with the key fully inserted into locking mechanism  106 , the key is rotated to cause elements  64  and  66  to be withdrawn from openings  68 . Upper base  32  is moved away from lower base  34  at least until belt wall  152  and support bar  153  clear edge  154  of lock assembly  106  and the tortuous path is eliminated. Belt  20  can then be slid with respect to buckle  18  either to tighten or loosen belt  20  around the detainee, or to remove end  150  of belt  20  from within buckle  18  altogether. 
   Wrist restraint system  10  is formed by riveting one end of belt  20  to end  170  of lower base  34  at openings  168  using bar  200 . The remaining, free, end of belt  20  is then inserted through end  172  of an unlocked buckle  14  and through buckle  14 . The free end is then inserted through end  174  of a second unlocked buckle  14  and through end  174  of buckle  18 . Buckles  14  are slid on belt  20  until they reach the desired location, and then they can be locked in place. To reposition a buckle  14 , buckle  14  is unlocked and slid on belt  20  until the new desired position is reached, at which point buckle  14  is again locked. Each wrist restraint is formed by inserting the free end of a wrist strap  22  and  24  into and through an unlocked buckle  16 , and pulling the free end until strap  22  or  24  is secured around the detainee&#39;s wrist. Buckle  16  is then locked. Restraints  22  and  24  can be tightened, loosened or completely unbuckled in the same manner as belt  20  is loosened, tightened or unlocked. 
   Leg restraint system  12  is formed by riveting strap  26  to the rear surface  167  of base  34  of each of a pair of buckles  18  with rivets  206  and  208  through holes  166  and  168  in base  34  and holes  202  and  204  of a pair of bars  200  intermediate the ends of strap  26 , as is shown in FIG.  3 A. In so doing, strap  26  has two free ends. Each free end of strap  26  is formed into a loop  28  or  30 , and each free end is inserted into end  174  of the unlocked buckles  18 . Loops  28  and  30  can then be tightened around the detainee&#39;s ankles. Loops  28  and  30  can be tightened, loosened or completely unbuckled in the same manner as belt  20  is loosened, tightened or unlocked. 
   Leg restraint system  12  can also be used as “handcuffs.” That is, leg restraint system  12  can be used to restrain the hands of a detainee where it is not necessary to secure the detainee&#39;s hands to the detainee&#39;s waist area. For example, system  12  can be used to restrain a detainee&#39;s hands around a fixed bar or similar element. In this instance, loops  28  and  30  are secured around the detainee&#39;s wrists in the same manner as loops  28  and  30  are secured around the detainee&#39;s ankles. The only difference is that strap  26  is typically much shorter when system  12  is used as a pair of handcuffs than it is when it is used as a leg restraint, since only 2 or 3 inches typically separate handcuffed hands. System  12  also can be used as shoulder restraints. 
   Additional changes may be made to the design of the invention. These variations should not be considered as a departure from the subject invention.

Summary:
A restraint system includes a wrist restraint system and an ankle restraint system that allow the limbs of a detainee to be restrained. The lockable wrist restraint system includes a waist belt and wrist restraints that are rotatably mounted to the waist belt. The wrist restraints can be positioned anywhere around the waist belt. The lockable ankle restraint system includes a strap and two buckles that form the strap into two loops. Each loop is used to restrain a leg of the detainee. A lockable buckle includes a housing that creates a tortuous path that traps a strap to which the buckle is mounted and prevents the strap from being adjusted or removed from the detainee.