GB2439088A

GB2439088A - Handcuffs with central locking plate

Info

Publication number: GB2439088A
Application number: GB0700630A
Authority: GB
Inventors: Andrew Rayner
Original assignee: Individual
Current assignee: Individual
Priority date: 2006-06-14
Filing date: 2007-01-12
Publication date: 2007-12-19
Also published as: GB0700630D0; GB0611753D0

Abstract

A pair of handcuffs having a first handcuff 10, a second handcuff and a locking mechanism 2, 4, 5, 6, the pair of handcuffs having two configurations, an unlocked configuration in which a swingarm 14, 15 of each handcuff may be released to open said handcuff, and a locked configuration in which said swingarm cannot be released, the pair of handcuffs comprising: a shackle; first and second swingarms 15 pivotally mounted on said shackle, each of said swingarms having a plurality of teeth 20 for engaging with a ratchet means 21; first and second spring-loaded arms 11 each having a ratchet portion configured to engage with said plurality of teeth 20; and first and second means 26 for manually disengaging each said ratchet portion from said plurality of teeth; and wherein the locking mechanism comprises a plate 4 disposed between said first spring-loaded arm and said second spring-loaded arm, said plate being configured to move between a first position in said locked configuration, in which each said ratchet portion may not be manually disengaged from said plurality of teeth, and a second position in said unlocked configuration, in which each said ratchet portion may be manually disengaged from said plurality of teeth.

Description

Personnel restraining device This invention relates to handcuffs, the

personal restraining devices as used by the police and other security services.

it is well-known among police professionals, and readily supported by documented statistics, that one of the most dangerous and vulnerable tasks performed by law enforcement officers is the procedure of handcuffing a suspect. A successful handcuiling cia suspect by an officer can therefore be defined as the securing of the suspcct's hands in a pair of handcuffs in a manner which minimiscs the officer's personal risk.

Conventional handcuffs feature a shackle with a ratchet mechanism and a arm which may rotate through 360 degrees in one direction due to the operation ci' the ratchet mechanism. A suspect may he handcuffed by putting the handcuff into a preset configuration with the arm rotated through most of the teeth positions in the ratchet mechanism so that it only need rotate through a small number of remaining teeth positions beFore it is Free oF the ratchet mechanism. The handcuFF is then applied to the suspccfs ann quickly so that the suspect's arm comes into contact with the handcuff ann and enough kinetic energy is transferred to the handcuff arm to cause it to rotate through a large angle free ol the ratchet mechanism and catch the first few ratchet teeth positions having rotated through an arc of between 270 degrees and 360 degrees.

This operation relies on the officer being able to apply the handcuffs to the suspect with sufficient rapidity to cause the handcuff arm to rotate through a large enough angle. and also on the oFFicer applying the handcuFf in such a manner that rotation of the handcuff arm is not impeded by the suspect's body or clothing. fliis requires a high degree of Practice and skill on the part of the officer and officers receive training with handcuffs U) order to achieve an appropriate level of skill.

US 5.463,884 describes a handcuff for dual use as a quick-release training device and an actual restraint device. Quick-release buttons arc mounted on opposite sides of the hail of (lie handcuti with the buttons being coupled to the pawl of the locking assembly via a quick-release shall lhr disengaging the pawl from the ratchet and unlocking the handcuff upon movement of the buttons The handculuis primarily ior use in training as it significantly reduces the time required to unlock and remove handculTh during training sessions.

However the handcuff still sutièrs from the problem that the handcuffing operation is difficult to perform and relies upon the handcuff ant being given enough kinetic energy to rotate though almost a complete circle unimpeded. Furthermore, the locking mechanism when the quick release mechanism is disabled still relies on a conventional rotating key. The officer niu.st hold the suspect's ann in place, insert the key in a handcuff with the proper alignment to the keyhole, rotate the key to lift the spring-biased pawl from the ratchet and manipulate the handcuff to open the bail.

Iniprovemenis to the current niainstrernn prior art handcuff designs have been made by addressing the key issues of speed, control, predictability and ease of use, each of which relate to the successful handcuffing of an suspect.

It is the design of the handeulTh that determines the manner in which they can be applied. A successful handcuffing can thus be achieved through the officer's maintenance of control over the suspect throughout the cuffing procedure and by minimising the stress of the suspect via a speedy and error free handcuffing.

l'hc key safety issues relate to each of three main sequential actions (application, adjustment and locking) an officer may perform during the handcuffing procedure. The improvements to the handcuffs relate specifically to design changes which improve the key safety issues lbr each of these three main actions (application, adjustment and loelcing).

We will describe a pair ol'handcuffs joined together by a pair of rigid cheekplates which comprise a central locking mechanism. The said handcuffs having two eon figurations, an unlocked configuration in which swingarms may he released to open each handcuff of said handcuffs mid a locked configuration in which said swingarms cannot be released, each said handcuff comprising a shackle, a swingarm of said swingarms pivotally mounted on said shackle, said swingarni having a plurality of' teeth for engaging with a ratchet means, a spring-loaded ann having a ratchet portion con figured to engage with said plurality of teeth, means for manually disengaging said ratchet portion from said plurality of teeth.

The said central locking n'ieehanisni comprising a central lock-plate being positioned centrally between said swingarms of said handcuffs. Preferably said lock-plate being configured to move between a first position in said locked configuration in which said raichet portion ol' each swingann of said handcuffs may not be manually disengaged from said plurality ol'teeth and a second position in said unlocked conf]guration in which said ratchet portion of each swingarm of said handcuffs may he manually disengaged from said plurality of teeth.

PreFerably the lock-plate has a receptacle (such as a socket or keyhole) for receiving a key. and preferably said receptacle contains a catch to retain said key. PreiCrably the lock-plate is spring-loaded and resiliently biased towards a locked configuration with the key in said receptacle (i.e. locked configuration) or without the key in said receptacle (i.e. double-locked configuration). Preferably the lock-plate may he moved to said unlocked configuration by depressing the key while in said receptacle.

Preferably the spring-loaded arm may he disengaged by manually operating a knob coupled to the spring-loaded arm so that the ratchet portion of the spring-loaded arm is moved away from the teeth. Preferably the knob is mounted on tile spring-loaded arm.

In sonic embodiments, there may be one spring-loaded arm and one knob on either side of the handcuff shackle, so that both knobs must be operated in order to release the handcuff.

According to an aspect of the present invention there is provided a pair of handcuffs having a first handcuff, a. second handcuff and a locking mechanjsm, the pair of handcuffs having two configurations, an unlocked configuration in which a swingarm of each handcufiniay he released to open said handcuff, and a locked configuration in which said swingarm cannot be released, the pair of handcuffs comprising: a shackle; first and second swingarms pivotally mounted on said shackle, each of said swingarms havmg a plurality olteeth for engaging with a raicliet means; first and second spring-loaded arms each having a ratchet portion configured to engage with said plurality of teeth; and first arid second means for manually disengaging each said ratchet portion from said plurality of teeth; and wherein the locking mechanism comprises a plate disposed between said first spring-loaded arm and said second spring-loaded arm, said plate being configured to move between a first position ill said locked configuration, in which each said ratchet portion may not he manually disengaged from said plurality of teeth, and a second position in said unlocked configuration. in which each said ratchet portion may be manually disengaged fi'om said l)lurality of teeth.

According to another aspect of the present invention there is provided a method of unlocking a pair of handcuffs, the pair of handcuffs having a first handcuff a second handcuff and a locking mechanism, the locking mechanism having having a plate, said plate having a receptacle, the method allowing unlocking of said first handcuff and said second handcufT substantially simultaneously, the method comprising inserting a key into the receptacle and depressing said key.

According to ftirther aspect of' tile present invention there is provided a handcuff having two con figurations, an unlocked configuration in which a swinganil may he released to open said handcuff, and a locked configuration in which said swingarm cannot be released, the handcuff comprising a shackle, said swingann pivotally mounted on said shackle, said swingarm having a plurality of teeth for engaging with a ratchet means, a spring-loaded ann having a ratchet portion configured to engage with said plurality of' teeth, means for manually disengaging said ratchet portion from said plurality of teeth, and a shaft disposed in said shackle, an end of said shaft being configured to contact a key in said unlocked configuration. said shaft being con figured to move between a first position iii said locked configuration in which said ratchet portion may not he manually disengaged from said plurality of teeth and a second position in said unlocked configuration in which said ratchet portion may he manually disengaged from said plurality of teeth.

Preferably thc shackle has a receptacle (such is a socket or keyhole) for receiving tile key, and the shall is configured to move (e.g. slide or rotate) when the key' is inserted in the receptacle. Preferably the sliafi is spring-loaded and one end of the shall has a canning surface, so that when the key is inserted in the receptacle a cainining action between the key and the end of tile shaft i)rovides the movement. Preferably the receptacle is a cylindrical socket and tile key is a cylindrical plug.

Preferably the spring-loaded ann may be disengaged by manually operating a knob coupled to the spring-loaded arm so that tile ratchet portion of the spring-loaded arm is moved away from the teeth. PreFerably (he knob is mounted on the spring-loaded arm.

In some embodiments, there may he one spring-loaded arm and one knob on either side of the handcuff shackle, so that both knobs must be operated in order to release tile handcuff According to a yet further aspect of tIle present invention there is provided a handcuff comprising a shackle, a horseshoe-shaped swingarm pivotaiiy niounted on said shackle.

and a locking means for locking said handcuff, wherein said swingarm is resiliently biased towards an open position and a rotation of said swingarm closes said handcuff Preferably a post is provided on the shackle or on the swingarni for engaging with the other in order to provide restricted rotation of the swingarm. preferably rotation in an are of less than 180 degrees, less than 135 degrees, less than 90 degrees or more preferably less than 60 degrees.

Preferably the swingarm comprises a pair of arms forming a horseshoe shape. One of the arms may he spring-loaded against the shackle, and the other free to rotate within a range of rotation constrained by a post on the shackle and an interlocking cutout on the other arm. I'his may provide a maximum angle between the two ants (e.g. a maximum horseshoe open position). Alternatively the first arm may be spring-loaded against the shackle and the second arm may he spnng-loaded against the first ann. When the handcuff is released the arms are biased to a handcuff open position with the horseshoe open, and when the handcuff is closed the second arm may he rotated relative to the first arm to close the horseshoe and hence provide a smaller opening for the suspect's arm.

Preferably one of the ends of the swingan-n bear against part of the shackle when the handcuff is in the closed position. This allows the horseshoe to be closed by rotating the second ann relative to the first.

According to a another aspect oF the present invention there is provided a method of' unlocking a handcuff, thc method comprising inserting a cyhindrica.1 cap key in a cylindrical receptacle in said handcuff.

l'he handcuff may he locked by a corresponding method of removing the cylindrical cap (or plug) key from the cylindrical receptacle in the handcuff Alternatively, insertion may lock the handcuff and removal may unlock the handcul'l'.

According to f'urther aspect of the present invention there is provided a method of applying a handcuff to a person. the method comprising placing a limb or other body part of said person in a horseshoe-shaped swingarnl of' said handcuff and rotating said swingarm through an angle of less than 180 degrees.

Features of the above described aspects of' the invention may be combined in any permutation. Furthermore, it will be understood by one skilled in the art that aspects of the invention may be applied to other forms of personnel restraining device, such as leg cuffs and thumb euf&.

Application involves the trapping of the wrists by enclosure in the handcuffs. this is a very important action as it takes the situation from a high risk unsecured suspect state to a reduced risk secured suspect state. As a result the speed at which the handculTh are applied is important. Increased speed of' application can be attained by using handcutTh which are easy to use. ensure a high probability that their application will result in secured wrists and allow for control of the suspect to he maintained throughout. The improvements that have been made to help achieve this in an embodiment of the invention include a restricted rotation torsion sprung bisected horseshoe shaped swingarm trap which allows for a quick single handed wrist trap manoeuvre freeing up the officer's other hand to maintain fill control over the wrist to be cuffed. The restricted rotation and shape of the swinga.rm trap also improves the predictability of application as unlike prior art handcuffs the swing arm does not have to rotate though a wide -320 degree arc and thus will not be prone to being impeded, for example, by the suspects wrist being too close to their body. Less application positional precision is therefore required due to this improvement. Another improvement relates to a single handed quick release mechanism which allows for an immediate reset of the handcuffs if the swingarm trap shuts alter a failed application. This enables the officer to maintain a grip on the suspect with one hand while quickly and easily resetting the handcuffs with the other hand.

Alter a successful application of th.e handcuffs and the situation is deemed safe enough, the officer is required to ensure that the handcuITh are not too tight around the wrists (impeding blood flow etc.). If the handcuffs are too tight then the adjustment phase is required where, once again, case, predictability, speed and maintaining control are important in continuing to minimise risk to the officer whilst mininlising stress to the suspect. In prior art handcufli a key is required to be inserted and rotated to release the swingarm for loosening. I'hc key must also be held in the rotated position during adjustment as it would spring back if released. This method is clumsy and awkward and removes the ability ol the officer to maintain a firm grip on the handcuffs with one hand thus decreasing the ability to maintain control over the suspect. Also, the need to insert a small key at the correct angle into a keyhole requires the olhcer to take his focus off the suspect further increasing the officer's risk. The single handed quick release mechanism as introduced in the application section is an improvement which helps to solve these problems by allowing the ollicer to adjust the tightness of the handcuffs around the wrists with ease, control, speed and predictability by allowing for the release of the swingarm while the officers hand retains a firm grip of the handcuffs and without the need to insert and control a key thereby allowing the officer to maintain his fbcus on the suspect at all times. In addition, it' the suspeci attempts to pull away during the adjustment the quick release mechanism resets disabling release as is the case with prior art handcuffs, however, if the suspect manages to pull away when using prior art handcuffs it is possible the key may he left caught in the handcuffs or may drop to the floor further complicating the procedure. The iniproveci handcuffs do not require a key process at this stage and are thus not prone to similar complications. the nature and positioning of the quick release mechanism in the improved handcuffs may prevent the suspect from releasing the swinganu themselves. Note: In both prior art and the improved handcuffs, the lightening of the swingarm around the suspects wrists can he achieved without the need for a key, it is inherently possible.

llic final phase in the handcuffing procedure is locking. This involves the setting of the handcuffs so that the swingarm remains fixed in place and cannot be loosened or tightened without explicit use of a key to reverse this state. Again. predicuthility, ease, control and speed are the important factors to consider in terms of the locking phase and its implementation with regard to an improved design of the mechanism. Improvements include the positioning of the key hole ihr vertical access as opposed to prior art handcuffs which have one sided horizontal access whereby the oiiieer must make sure that the handcuffs are fitted in a specific orientation so that the key holes are not lacing the sLtspects body which would impede access. The vertical access positioning in contrast allows for minimal obstruction regardless of the orientatlon that the handcuffs are fitted. A ftirthcr improvement relates to the shape olthe key, it is a straight tube with no protruding teeth that enables insertion at any rotational angle. l'his, in conjLinccion with the vertical access, allows t.he officer to insert the key blind if need he, keeping focus on the suspect.

Further, in one embodiment of the invention, only the single action of depressing the key while inserted is required to unlock the handcuffs for application or removal. On releasing the key the spring loaded locking nieelianisni automatically returns the handcuffs to a locked state. I)oublc-locking the handcuffs can he achieved by withdrawal of the key from the handcuffs. Use of a hungi cord or retractable ski pass holdef type mechanism with a catch and attached to the officer's webbing may be used to clip onto and withdraw the key (double-locking). This allows the officer to clip catch onto the key while in the first locked state in preparation for double-lockin.g (withdrawal of the key) the handcuffs. This enhances security during an adj ustment because ii' the suspect attempts to evade the officer the key is automatically pulled from the lock thus doubl c-I ocking tile handcuffs.

Further, in another embodiment of' the invention, only the single action of insertion is required to unlock the handcuffs. Similarly, (lie single action of withdrawing the key locks the handcuffs. While the handcuffs are unlocked the key is retained in the lock and can be separated from a male counterpart of a pull-apart' keyring. The separated key is fully retained by the lock and does not protrude. Withdraw! of the key (locking) can only occur by insertion of the male end o!'the pull-apart' keyring which, by way of a further improvement, is attached by a hungi cord or retractable ski pass holder' type mechanism to the officers webbing. This allows the officer to insert the male end of the pull-apart' keyring into the key while in the unlocked state in preparation for locking the handcuffs. This enhances security during an adjustment because if the suspect attempts to evade the officer the keys are automatically pulled from the locks thus locking the handcuffs.

An additional benefit of these design improvements, in particular as a result of the ease of use in terms of quick adjustment and release, relates to training. In one embodiment, the application and release of the handcuffs can he perionned rapidly as there is no need thr alternate insertion and withdrawal of the key (the key is retained in the lock for all phases until double-locking is required). In another embodiment, the application and release of the handcuffs can be per!brnied without application of a key and thus rapidly.

This encourages regular practice to attain and maintain proficiency and confidence in the handcuffing procedure.

Also, the improvements have been designed in such a way as to minimise extra complexity so as to ensure that the handeuffl are robust mid that their manufacture costs are kept to a minimum. The handcuffs general shape and dimensions have been retained so as to enable their holstering in a similar fashion to existing handcuffs.

F.mbodiments of these arid other aspects of the invention will now he described in detail, with reference to the accompanying drawings, in which: Figure 1 shows a detailed plan view of a pair of the wrist cuffs joined by a central locking mechanism, Figure 2 shows simplified plan views ola pair ol wrist culls showing various states of Operation: 2A. Open and locked (single-locked i.e. key in and not depressed).

2B. Closing and unlocked (i.e. key in and depressed).

2C. Closed and locked (single-locked i.e. key in and not depressed).

2D. Closed and double-locked (i.e. key is withdrawn).

2F. Opening and unlocked (i.e. key in and depressed).

F'igure 3 shows a plan view ala pair of the wrist cuffs with example solid bar join.

Figure 4 shows a detailed plan view of one wrist cuff and key set.

Figure SA shows a plan view of the leading and trailing sections of the swingarni (separated) with A(i), an exploded sectional view olthe swingann-cheekplate shoulder coupling.

Figure SB shows a plan view of one cheekplate.

Figure SC shows a plan view of one wrist euf! in a closed position and locked (key removed) with C(i) a sectional view of the catclunent arid locking mechanism through the nipple lever and C(ii) sectional view of the catchinent arid locking mechanism through the locking tooth.

Figure 6 shows simplified plan views of a wrist cuff showing various states of operation: 6A. Unlocked (key in) and closing.

GB. Unlocked, with depressed catehinent releasing the swingarm to open.

6C. Unlocked, closing and inserting the key-pull into the key Ihr locking.

61). Closed and withdrawing the key to release the locking shaft and lock the cuffs.

In a first embodiment of the invention, the handcuffs comprise a pair of wrist cuffs Fig.l that may he joined together by a pair of cheek plates Fig.1(10) which sandwich together all the other parts of the handcuffs which include the foundation blocks Fig. 1(3,7), swingarn-i Fig. 1(1 4,1 5), catchment Fig. 1 (8,11) and central locking mechanism Fig. I (2,45,6) with key Fig. 1(1). The cheekplates are shaped to provide a shoulder Fig. 1(16) to connect to the swingarm at Fig. 1(17). ajaw Fig. 1(11) to receive the swingarm ends in the c.atch.ment and a torso Fig. 1(19) to connect, to the other wrist cuff Each cuff as depicted in 1:1g. 1 comprises a bisected swinganri (1 4,1 5), pivotally connected Fig.1 (17) at the bisection to the shoulder Fig. 1 (16) ola cheek plate assembly Fig.1 (10). The two arms of the bisected swingarm will be referred to as (lie leading anti Fig.1 (14) and the trailing arm Fig.1 (15). These arms are able to he collapsed together about the pivot connection Fig. 1 (1 7). The end of the trailing arm has a set of ratchet teeth Fig.1 (20) which interact with the ratchet teeth Fig.l (21) of the jaw Fig. 1 (11) of' the catchrnent Fig.! (8,11) during a closing manoeuvre. flie end of the leading anti Fig.1 (22) is smooth and does not interact with the catchment.

A stop rod Fig.l (1 8) is connected between the cheek plates alongside the rotation track oithe leading arm Fig.l (14). I'he rotational distance of the leading arm in both the opening and closing directions is governed by the stop rod Fig.l (18). A pull-push linkage Fig. 1 (23) exists between the leading and trailing arms which allows the leading arm to pull the trailing arm into a closed position Fig.2(A) when closing and allows the trailing arm to push the leading arm back to a reset position Fig.2(A) on release Fig.2(F).

The trailing arm Fig. 1 (15) is torsion spring loaded around the pivot Fig. 1 (1 7)111 relation to its adjacent cheekplate shoulder Fig. 1 (16). The direction of' torque is towards an open position (resel.) Fig.2(A) ensuring a primed state until forced to a closed state Fig.2(B,C,D) by a force acting on the leading arm in a closing direction Fig.2(A28) thus pulling tile trailing arm or by a three acting on the trailing anti in a closing direction Fig.2(B3 0).

The ability for a force acting on the leading arm in a closing direction to trap a suspects wrist (the normal operation) relies on the pulled trailing ant's teeth Fig.] (2)) to reach the catchn-ient jaws teeth Fig. 1(21) before the leading arm Fig. 1 (14) disappears between the cheek plates of the shoulder section disabling the force being applied. l'hcrelbre the shape of the cheekplates shoulder section in relation to the shape of the swingami (leading and trailing arms) is such that it allows 11w enough travel of the leading arm pno] to disappearing between the cheekplates shoulder section to ensure the trailing arms' teeth have engaged sufficiently with the catclirnent teeth to have trapped the wrist.

The ability for the leading and trailing an-us to collapse together as a result of their bisection about the pivot Fig. 1(17) allows for the leading ann to remain in a flush position in relation to the cheek plates shoulder section so that Ihe leading arm will not protrude liom the other side of the cheek plate shoulder section no matter how thr the trailing arm travels in the closing position Fig2.(B30). if the leading arm were able to protrude then it would act as an unwanted pointed snare.

The eatehrneni and locking mechanism may each be paired about a central fixed plate.

The shape and function of each part of the pair is identical while their positions are symmetrical about the vertical and sandwich the lixed plate. Each pail of the pair operate independently. But worked together produce the same functional outcome.

the catchment is a sprung curved arm (jaw Fig.l(1 1)) with a set of ratchet teeth Fig. I (21) and is used to receive the trailing aim by interlocking their teeth. The catchment is pivoted Fig.l (9) at the shoulder side of the cheek plates. its spring Fig.1 (8) is positioned close to the pivot lying between the underside of the catehment and topside of the main section of the Iuiundation block Fig.! (7) so that its force is directed towards the swing arrn's teeth. The catchrnent is restrained froni being Pushed by its spring out of the jaw part of the cheek plates by a stop-rod Fig.] (13) which passes through a larger hole in the catchnient jaw Fig.1 (11).

A dorsally protruding knob Fig.l (26) at the end of the eatchnient provides a lever which is used by the operator of the handcuffs to disengage the interlocked teeth of the catcbment and trailing arm teeth by pushing down on the lever thus rotating the catchment around its pivot away from the trailing arm teeth thus releasing the trailing ann.

Locking tooth receptacles (24) are positioned on the underside of the catchment away from its pivot. Ihe receptacle is used in conjunction with the locking mechanisms' lock-plate locking teeth Fig. 1(25) to allow for a locked or unlocked state depending on their relative positions.

The locking mechanism comprises a sprung lock-plate(4) and key (1). The lock-plate lies between and adjacent to the base of each of the hand cuff catchrnents away from the calchments pivot. It. has locking teeth (25) positioned adjacent to the catchments locking tooth receptacles (24). Springs (6) are positioned at the opposite side to the key acting against the lock-plate so that the lock-plate is biased to a locked position Fig.2(A,C,D).

A sprung catch Fig. 1(2.5) is used to keep the key (I) in position until!hrcihly removed. In a second embodiment of the invention, the handcuffs are similar to

the prior art in a few respects. They comprise a pair of wrist cuffs Fig.3(l) that may be joined together by various prior art means (solid bar Fig.3(2), chain, swivel link etc.). Each wrist cuff Fig.4 comprises a pair of check plates Fig.4(3a h) & Fig.6(33) which sandwich together all the oilier parts which include the foundation block Fig.4(6), swingann Fig.4(4+5), catchinent Fig.4 (7-19111) and locking mechanism Fig.4(8+l0) with key Iig.4(l3 14). The cheekplates am shaped to provide a shoulder Fig.4(20) to connect to the swingarm at Fig.4(21), ajaw Fig.4(7) to receive the swingarni ends in the catchmein and a torso Fig.4(22) to connect to the other Wrist cuff Illustrated in lig.3 is a set of handculTh which comprise two wrist cuffs (1) linked together by a solid flat bar 2 (as an example of linkage type).

Each cuff as depicted in Fig.4 coniprises a bisected swingarm (4 5). pivotally connected (21) at the bisection to the shoulder (20) of a cheek plate assembly (3a+b).

The two arms of the bisected swingarin will he referred to as the leading arm (5) and the trailing ann (4). These arms are able to be collapsed together about the pivot connection (21). The end of the trailing anti has a set oFratehet teeth (30) which interact with the ratchet teeth (11) of the jaw (7) of the eatehnieni (7+9+11) during a closing manoeuvre.

The end of the leading arm (23) is smooth and does not interact with the catchment.

A stop rod (24) is connected between the cheek plates alongside the rotation track (25) of the leading arm (5). The rotational distance of the leading arm in both the opening and closing directions is governed by the stop rod in relation to a leading arm rear stop (26) and a leading arm fore stop (27). The rotational distance olihe trailing arm is governed by the stop rod in relation to a trailing arm rear stop (29) for the opening direction, in the closing direction the trailing arm is governed by the position of the leading arm. I'hese stops (26) and (29) also form the pull-push linkage which allows the leading arm to pull the trailing ann into a closed position Fig.6(C,D) when closing and allows the trailing arm to push the leading arm back to a reset position Fig.6(A) on release Fig.6(R).

The trailing ann (4) is torsion spring loaded Fig.5( 18) around the pivot (24) in relation to its adjacent cheekplate shoulder (20). lEe direction of torque is towards an open position (reset) Fig.6(A) ensuring a primed state until forced to a closed state Fig.6(C.D) by a force acting on the leading arm in a closing direction Fig.6(Aa) thus pulling the trailing arm or by a force acting on the trailing arm in a closing direction Fig.6(Ah). Fig.5(A) shows the stepped configuration of the leading and trailing aims in relation to one another and the cheek plates which enable their limited rotation about the pivot join. [he position of the torsion spring Fig.5(i 8) in relation to the trailing arm and its adjacent cheekplate is also shown sunk in its own circular groove about the pivot partially in the trailing arm and partially in the cheekplate.

The ability for a force acting on the leading arm in a closing direction to trap a suspects wrist (the normal operation) relies on the pulled trailing ant's teeth Fig.4(30) to reach the catch.ment jaws teeth Fig.4(ll) before the leading arm disappears between the cheek plates of the shoulder section disabling the force being applied. Therefore the shape of the chcekplates shoulder section in relation to the shape of the swingarm (leading and trailing arms) is such that it allows for enough travel of the leading an-n prior to disappearing between the cheekplates shoulder section to ensure the trailing arms' teeth have engaged sufficiently vith the catehnient teeth to have trapped the wrist.

the ability for the leading and trailing arms to collapse together as a result of'their slops Fig.4(26.27,29) configuration allows (or the leading arm to remain in a flush position in relation to the cheek plates shoulder section so that the leading arm will not protrude from the other side of the cheek Plate shoulder section no matter how far the trailing ant travels in the closing position Fig4.(D). If the leading ann where able protrude then it would act as an unwanted pointed snare.

The catchment and locking mechanism arc each paired about a central fixed plate, sec the cross sectional view in Fig.6(C). I'he shape and function of each part of the pair is identical while their positions are symmetrical about the vertical (with respect to Fig.6(C12)) and sandwich the lixed plate Fig.6(C12). Each part of the pair operate independently. But worked together produce the same functional outcome. I.e. when the eatchrnent pair are depressed the swingarm is released and when the locking mechanism pair is engaged by the key the caicliment becomes unlocked (or locked if disengaged).

The catchment is a sprung curved arm (Jaw (7)) with a set of ratchet teeth 11 and is used to receive the trailing arm by interlocking their teeth. The catchment is pivoted (31) at the shoulder side of the cheek plates. Its spring (9) is positioned close to the pivot lying between the underside 1' the catchment and topside of the main section of the foundation block 6 so that its force is directed towards the swing arm's teeth. The eatehment is restrained from being pushed by its spring out of the jaw part of the cheek plates by an overlapping piece (32) of the minor section of the foundation block (6).

A widened section towards the middle of the catchmenl. provides the position of its nipple lever (33) which protrudes laterally through an opening (34) in its adjacent cheek plate. The nipple lever is used by the operator of the handcuffs to disengage the interlocked teeth of the catchment and trailing arm teeth by pushing down on the lever nipple thus rotating the catchinent around its pivot away from the trailing arm teeth thus releasing the trailing arm.

A locking tooth receptacle (19) is positioned on the underside and towards the end of the catchmcnt away from its pivot. The receptacle is used in conjunction with the locking mechanism to allow for an unlocked state.

The locking mechanism comprises a pair of sprung locking shafts (1 0) and key (13).

l'hc locking shall is a straight bar which lies along the base of the catchrnent away from the catchmcnts pivot. It has a locking tooth (37) positioned at the end ftirthest from tile catchment pivot (31) while thc other end of the locking shaft is wedge shaped (36). A spring (8) is positioned at the locking tooth cnd of the locking shalt between the locking shall and the Ibundation block so that its force is parallel to the length of the locking shaft.

A cylindrical lock barrel (35) used to house the key lies perpendicular to both locking shafts and intersects the locking shafts at their wedge shaped side (36). The key (13) is also cylindrical and is sized to fit flush into the lock barrel. An angled leading edge alows the key to push the locking shafts towards their spring end increasing tension.

When the key is pushed ftilly home in the lock barrel, a small v-shaped groove (38) running around the width of the key is exposed to the locking shafts wedges which fall into the valley trapping the key in the lock balTel (35).

When the key is ftilly inserted into the lock balTel the locking tooth (37) on each locking shaft will have been pushed to a position adjacent to the locking tooth receptacle (19) on the catchment. This is the unlocked state and allows free movement of' the catcliment.

When the key is removed from the lock barrel the locking shafts move toward the lock barrel by the force of the locking shafts spring acting on them. As a result the locking tooth of' the locking shaft becomes displaced from its alignment with the catchment locking tooth receptacle. This is the locked state whereby movement of'the catchment is impeded by-the locking shafts locking tooth.

The key (13) is hollowed at its rear and is designed as the female part of a pull-apart' keyring (13+14+15). Detaching the keyring allows the key to he left in the lock barrel flush with the surface olthe handculTh and unable to be removed by hand (unlocked handcuff state). To remove the key (locking the handcuff) the male pail of the keyring is clipped into the key and pulled, ibis releases the key from the locking shafts wedge grip on the key's groove (38) allowing the key to slide out of the lock barrel thus releasing the locking shafts and unlocking the handcuff as previously described.

The kcyring is connected to the officer by means ola cord (16) and catch (17). The cord could be in the form of a coiled bungi (16) or ski-pass holder type mechanism (not shown).

Further aspects of the invention are described in the following clauses: 1. A pair of handcuffs joined together by a central locking mechanism and having two prin-iary configurations, an unlocked configuration iii which a swingarm may be released to open each handcuff, and a locked configuration in which said swingarm of each handcuff cannot he released, each handcuff con-ipri sing: a shackle; said swingarm pivotally mounted on said shackle, said swingarin having a plurality of teeth I br engaging with a ratchet means; a spring-loaded ann having a ratchet portion configured to engage with said plurality of teeth; and means for manually disengaging said ratchet portion from said plurality of teeth.

l'he central locking niechani sm compri sing: A lock-plate centrally positioned between said spring-loaded anns of each said handcuff, and said lock-plate being configured to move between a Iirst position in said locked configuration in which said ratchet portion may not be manually disengaged from said plurality of teeth and a second position in said unlocked configuration in which said ratchet portion may he manually disengaged from said plurality of teeth.

2. Each pair of handcuffs according to clause 1, wherein said lock-plate further comprises a receptacle I br receiving a key, said lock-plate being configured to be able to be moved when said key is inserted in said receptacle.

3. Each pair of handcuffs according to clause 2, wherein said lock-plate is spring- loaded, and said key once inserted in said receptacle can be depressed so that said lock-plate moves from said locked configuration to said unlocked configuration.

4. Each pair of handcuffs according to clause 2 or 3, wherein said receptacle comprises a cylindrical socket, and said key comprises a cylindrical plug.

5. Each said handcuff according to any one of clauses ito 4, wherein said means for manually disengaging comprises a knob coupled to said spring-loaded arm.

6. Each said handcuff according to clause 5, wherein said spring-loaded ann comprises said knob.

7. Each said handcuff comprising: a shackle; and a horseshoe-shaped swingann pivotally mounted on said shackle; and a locking means for locking said handcuff, wherein said swingarm is resiliently biased towards an open position and a rotation of said swingarni closes said handcuiL 8. Each handcuff according to clause 7, wherein said shackle has a post for engaging with a cam oii said swingarm for providing restricted rotation.

9. Each handcuff according to clause 7 or 8 wherein said swingarm comprises a pair of anns forming a horseshoe shape.

10. Each handcuff according to clause 9, wherein said pair of arms comprises a first arm spring-loaded against said shackle and a second arm having rotation constrained by a post on said shackle and by said first arm.

II. Each handcuff according to clause 9, wherein said lair of'arrns comprises a first arm spring-loaded against said shackle and a second arm spring-loaded against said first arni so that an angle subtended by said first arm and said second ann may be manually varied.

12. Each handcufT according to any one of clauses 7 to Ii, wherein one or more ends of said swingarm bear against part of said shackle when said handcuff is in a closed position.

13. A method of' unlocking both handcufk simultaneously, the method comprising depressing said key while inserted in said receptacle in said lock-plate in said central locking mechanism of said handcuffs.

No doubt many other effective alternatives will occur to the skilled peison. It will he understood that the invention is not limited to the described embodiments and encompasses modifications apparent to those skilled in the art lying within the spirit and scope of the claims appended hereto.

Claims

CLAIMS: 1. A pair of handcuffs having a first handcuff, a second

handcuff and a locking mechanism, the pair of handcuffs having two configurations, an unlocked configuration in which a swingarm of each handcuff may be released to open said handcufl and a locked conFiguration in which said swingarm cannot be released, the pair of handculTh comprising: a shackle; first and second swingarms pivotally mounted on said shackle, each of said swingarnis having a plurality of teeth for engaging with a ratchet means; first and second spring-loaded arms each having a ratchet portion configured to engage with said plurality oF teeth; and first and second means for manually disengaging each said ratchet portion from said plurality of teeth; and wherein the locking mechanism comprises a plate disposed between said first spring-loaded ann and said second spring-loaded arm, said plate being configured to move between a first position in said locked configuration, in which each said ratchet portion may not be manually disengaged from said plurality of teeth, and a second position in said unlocked configuration, in which each said ratchet portion may be manual I y di seiigaged from said plurality of teeth.

2. A pair of handeulTh according to claim I, wherein said plate ftLrther comprises a receptacle ibr receiving a key, said plate being configured to be movable when a said key is inserted in said receptacle.

3. A pair of handcuffs according to claim 2, wherein said plate is spring-loaded, the pair of handcuffs being configured so that when a said key is inserted in said receptacle, said lock-plate moves From said locked configuration to said unlocked configuration when the said key is depressed.

4. A pair of handcuffs according to claim 2 or 3, wherein said receptacle comprises a cylindrical socket, and the said key comprises a cylindrical plug.

5. A pair of handcuffs according to any one of claims ito 4, wherein one of said means for manually disengaging comprises a knob coupled to said spring-loaded arm.

6. A pair of handcuffs according to claim 5. wherein said spring-loaded anii comprises said knob.

7. A method of unlocking a pair of handcuffs, the pair of'handcuffs having a first handcuff, a second handcuff and a locking mechanism, the locking mechanism having a plate, said plate having a receptacle, the method allowing unlocking of said first handcuff and said second handcuff substantially simultaneously, the method comprising inserting a key into the receptacle and depressing said key.

8. A handcuff having two configurations, an unlocked configuration in which a swingarm may be released to open said handcuff, and a locked configuration in which said swingan'n cannot be released, the handcuff comprising: a shackle; said swingarm pivotally mounted on said shackle, said swingarni having a plurality of teeth for engaging with a ratchet means; a spring-loaded arm having a ratchet portion configured to engage with said plurality of' teeth; means for manually disengaging said ratchet portion from said plurality of teeth; and a shaft disposed in said shackle, an end of said shaft being configured to contact a key in said unlocked configuration, said shalt being configured to move between a first position in said locked configuration in which said ratchet portion may not be manually disengaged from said plurality of teeth arid a second position in said unlocked configuration in which said ratchet portion may be manually disengaged from said plurality of teeth.

9. A handcuff according to claim 8, wherein said shackle further comprises a receptacle for receiving said key, said shaft being configured to move when said key is inseTted in said receptacle.

10. A handcuff according to claim 9. wherein said shaft is spring-loaded, said end of said shaft compriscs a camming surface, and wherein said shaft is configured to provide a caniming action between said cnd of said shalt and said key when said key is inserted in said receptacle.

Ii. A handculI according to claim 8 or 9. wherein said receptacle comprises a cylindrical socket, and said key comprises a cylindrical plug.

12. A handcuff according to any one of claims 8 to ii, wherein said means for manually disengaging comprises a knob coupled to said spring-loaded arm.

13. A handcuff according to claim 12, wherein said spring-loaded arm comprises said knob.

14. A handculfconiprising: a shackle; a horseshoe-shaped swingarm pivotally mounted on said shackle; and a locking means for locking said handcuff, vhcrein said swingarm is resiliently biased towards an open position and a rotation of said swingarm closes said handcuff.

1 5. A handcuff according to claim 14, wherein said shackle has a post for engaging with a earn on said swingarrn lbr providing restricted rotation.

16. A handcuff according to claim l4or 15 wherein said swingarm comprises a pair of anus forming a horseshoe shape.

17. A handcuff according to claim 16, wherein said pair of arms comprises a first arm spring-loaded against said shackle and a second arm having rotation constrained by a post on said shackle and by said first arm.

18. A handcuff according to claim 1 6, wherein said pair o:l' wins comprises a first arm spring-loaded against said shackle and a second ann spring-loaded against said first ann so that an angle subtended by said first arm and said second ann may he manually varied.

19. A handcuff according to any one of'claims 14 to 18. wherein one or more ends of said swingarm bear against part of said shackle when said handcuiTis in a closed position.

20. A method of unlocking a handcuff, the method comprising inserting a cylindrical cap key in a cylindrical receptacle in said handcuff'.

21. A method of'applying a handcuff to a person, the method comprising placing a limb or other body part of' said person iii a horseshoe-shapcd swingarni of said handcuff' and rotating said swingarin through an angle of' less than 1 80 degrees.

22. A pair of handcuffs, handcuff or method substantially as described herein with reference to the accompanying drawings.