The invention is to design a handcuff with an automatic locking mechanism that is easy to engage even when an individual is struggling or being non-compliant with police officer's direction. The current handcuffs in recent use by the police utilize an intricate double lock. The double lock is enabled once the handcuffs are placed on an individual to prevent possible injury from self-tightening when in use. The lock is engaged by flipping a very small lever inside the key hole of the handcuff using the opposite end of the handcuff key, is referred to as a double lock tip or actuator. The locking mechanism is activated by manual and is often difficult or not possible to engage when officer apprehension involves a struggle, leading to difficulties in placing an individual in handcuffs. The invention disclosure is to employ an automatic pressure-activated mechanism to locking the handcuff and prevent the handcuff from further tightening.
An automatic over-tightening prevention mechanism is added on the moving strand of handcuff; the moving strand comprises three parts (instead of a single part in conventional handcuff):
1, two forward ratchets (left and right ratchets) are placed in two sides of the moving strand,
2, and one stop ratchet is placed in between the two forward ratchets,
The overall shape of the moving strand keeps the same as that of conventional handcuff; the forward ratchets work in exact the same way of conventional handcuff.
The stop ratchet is kept within the two forward ratchets and in left-most position when no force is applied on; and the stop ratchet rotates and moves outwards of the two forward ratchets when a force greater than 1.5 lbs is applied on its inner side, and then the stop ratchet is stopped by a stop pawl and further tightening of the handcuff is prevented.
When the handcuff is restraining on a wrist or an ankle, a force (>1.5 lbs or any preferred force) will be applied on the stop ratchet at the inner side of the stop ratchet, then stop ratchet is immediately engaged and locked by the stop pawl, and then the moving strand as a whole is securely locked. Further tightening of the handcuff is prevented.
The invention eliminates the manually operated push-to-locking latch in conventional handcuff without compromising any function.
The handcuff has the same shape/size as conventional handcuff; there are no sharp or rough edges or any additional hazardous parts added.
The handcuff is triple-locked after engaged on wrist or ankle, and cannot be tampered with simple tools. The stop pawl or lock stops any further tightening, and the other two forward ratchets prevent the device from picking or shimming.
The handcuffs can be engaged and locked 50% faster than a conventional one by automatically locking instead of manually push-to-locking, the handcuff can be easily removed by police officer with a special key, and again is 50% faster than conventional one to remove.
One of the embodiments of the invention is provided:
A handcuff with automatic over-tightening-prevention mechanism comprises a double strand and
a moving strand,
the moving strand further comprises:
a left ratchet, which is paired with a left stop pawl,
a right ratchet, which is paired with a right stop pawl,
a stop ratchet, which is paired with a middle stop pawl,
a first rivet,
a second rivet,
a tension spring,
wherein the stop ratchet is positioned in between the left and right ratchets,
wherein when the stop ratchet is pressed from inner side, it rotates and moves outwards of the left and right ratchets,
wherein when the stop ratchet is pressed towards its outmost position, it is engaged with the middle stop pawl and is stopped by the middle stop pawl; wherein further tightening of the handcuff is prevented when the stop ratchet is engaged with the middle stop pawl,
wherein the moving strand rotates around the first rivet,
wherein the stop ratchet rotates around the second rivet,
wherein the rotation of the stop ratchet is constrained by the tension spring, when force applied on the inner side of the stop ratchet is greater than equivalent tension force of the tension spring, the stop ratchet rotates clockwise, or moves outwards of the left and right ratchets; when force applied on the inner side of the stop ratchet is less than the equivalent tension force of the tension spring, the stop ratchet rotates counter clockwise, or moves inwards of the left and right ratchets.
Another embodiment of the invention is provided:
Wherein the above example, the left ratchet and its paired stop pawl are not necessities, the left ratchet can be different in shape and in teeth in comparison to the right ratchet, for example, the left ratchet can be tooth-free, and the left stop pawl can be eliminated, and the forward engagement or restraining functions of the handcuff can be performed by the right ratchet and its paired right stop pawl, and over-tightening-prevention functions can be performed by the middle stop ratchet; this configuration makes handcuff more flexible in manufacturing without compromising most functions.
And another embodiment of the invention is provided:
Wherein the first example, the left ratchet and its paired stop pawl are not necessities, both the left ratchet and its paired stop pawl can eliminated, and the forward engagement or restraining functions of the handcuff can be performed by the right ratchet and its paired stop pawl, and over-tightening-prevention functions can be performed by the stop ratchet and its stop pawl, this configuration makes handcuff very simple in manufacturing without compromising basic functions.
The present application is a continuation of U.S. Provisional Patent Application No. 63/210,043 filed on 13 Jun. 2021.
And the present application claims the benefit of U.S. Provisional Patent Application No. 63/210,043 filed on 13 Jun. 2021.
Provisional Patent 63/210,043 is incorporated herein by reference in its entirety.
It is to be understood that the disclosure is not limited in its application to the details of the embodiments as set forth in the following description. The invention is capable of other embodiments and of being practiced or of being carried out in various ways.
Furthermore, it is to be understood that the terminology used herein is for the purpose of description and should not be regarded as limiting. Contrary to the use of the term “consisting”, the use of the terms “including”, “containing”, “comprising”, or “having” and variations thereof is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. The use of the term “a” or “an” is meant to encompass “one or more”. Any numerical range recited herein is intended to include all values from the lower value to the upper value of that range.
Graphics are used in order to simplify the descriptions. Most of the sizes or the parameters in the graphics are scaled for ease of understanding, or are normalized at given conditions. The graphics show a mutual contrast relationship instead of the actual sizes or values.
The directions and positions used in the description, such as up, down, vertically, horizontally, left, right, inwards, outwards, inner, inmost, outmost, clockwise and counter-clockwise are based on the relative directions and relative positions shown in the Figures, and are not necessarily the directions and positions in actual real-life applications.
The engagement of the handcuff means a wrist or a ankle is handcuffed and removal of handcuff is not available without a special key; the engagement of the stop ratchet means a wrist or a ankle is handcuffed and locked, or the lock mechanism is activated, and further tightening of the handcuff is not available unless the force applied on the wrist or ankle is removed or reduced.
In the present invention, two measures are added on the basic functions of a conventional handcuff:
1, Two ratchets (left and right ratchets) are used to engage the moving strand and prevent the moving strand from rotating backwards (or loosening), two ratchets engage with two independent stop pawls to increase the degree of difficulty of unwanted picking or shimming.
2, A stop ratchet paired with a middle stop pawl (or a third pawl) is added to limit the tightening force applied on wrist or ankle. When the stop ratchet is being pressed, it rotates clockwise. When the stop ratchet engages with the third stop pawl, it is engaged and locked and further tightening is prevented. And a tension spring is used to control or preset a equivalent tension force, when force applied on the ratchet is greater than the equivalent force, the stop ratchet is engaged and the handcuff is locked; when force applied on the ratchet is smaller than the equivalent force, the stop ratchet is not engaged or not locked, and then the handcuff is be engaged but not locked, and the handcuff can be further tightened.
3, The engagement of the handcuff is independent of the engagement of the stop ratchet. The engagement of the handcuff prevents the handcuff from loosening or prevents the moving strand from rotating in clockwise direction; this engagement is independent of the force applied on the inner side of the stop ratchet. The engagement of the stop ratchet prevents the handcuff from further tightening or prevents the moving strand from rotating in counter clockwise direction, this engagement is independent of the forward movement or clockwise movement of the moving strand of the handcuff.
4, The handcuff of the invention can be easily engaged and locked like a conventional handcuff without manually pushing the lock latch. The handcuff can be easily disengaged and unlocked like a conventional handcuff with a special key and without manually reset the lock latch. The handcuff is over-tighten-prevented automatically regardless how fast the handcuffing is being procedure, or how hard the restrained one is fighting in being handcuffed. The handcuff of the invention is much quick and much safer in operation.
Refer to
Refer to
It is to be noticed that the direction of the teeth of the paired stop ratchet is opposed to the direction of the teeth of left ratchet; the direction of the teeth of paired stop ratchet is opposed to the direction of the teeth of right ratchet.
A further detailed explanation of the moving strand 102 is shown in
Another detailed explanation of the moving strand 102 is shown in
An exploded illustration of the moving strand 102 is shown in
Another exploded illustration of the moving strand 102 is shown in
Both left stop pawls 1071 and right stop pawl 107 are constrained by pawl tension springs respectively, the said pawl tension springs push the left and/or right stop pawls to rotate clockwise and engage with the left and right ratchets 103 and/or 105 respectively. Right stop pawl 107 and its pawl tension spring 207 are shown in
The remaining parts of the handcuff (keys, swivels, links and the double strand) are similar to conventional ones which have been used for hundreds years, and are not further detailed in the description.
The swivel-chain links of the handcuff can be hinge links or rigid links.
The teeth 111 and 109 can be arranged with an offset, or the pawl 107 and 1071 can be arranged with an offset in clockwise or counter clockwise direction to increase the degree of difficulty in picking or shimming.
The example in above description can be simplified by eliminating the teeth of left ratchet 103 and eliminating the left stop pawl paired with the left ratchet 103.
The example in above description can be further simplified by eliminating both the left ratchet 103 and the left stop pawl paired with the left ratchet 103.
The invention meets six advantage conditions at same time:
A, automatic over tightening prevention without manual push-to-lock latch,
B, same size can be maintained as conventional handcuff,
C, same shape can be maintained as conventional one,
D, same handcuffing steps or procedures as conventional one,
E, faster or less complicated in restraining and removal,
F, very hard to be picked or shimmed because the handcuff can be removed only when both the right stop pawl 107 and left stop pawl 1071 are released simultaneously.
And there are more preferred outcomes,
1, an automatic over-tightening prevention mechanism is added in the moving strand, the manufacturing of the handcuff is almost the same as conventional one,
2, eliminate manually operated the push-to-lock latch in conventional handcuff without compromising any function,
3, reduce the restraining/removal time by 50% in handcuffing,
The proposed handcuff provides a reliable over-tighten-prevention solution while keeps maximizing the compatibility with conventional handcuff (keep unchanged in size, shape, weight, application SOP and training).
The key innovations:
a), the moving strand comprises three parts (instead of a single part in conventional handcuff): two forward ratchets in two sides (left and right) and one stop ratchet in between, the overall shape of the moving strand is the same as that of conventional handcuff.
b), the forward ratchets work in exact same way of conventional handcuff.
c), the stop ratchet is kept within the two forward ratchets and left limiter when no force is applied on; and the stop ratchet is moved outwards of the two forward ratchets when a force greater than 1.5 lbs is applied on and then is stopped by a stop pawl.
d), When the handcuff is restrained on a wrist or ankle, a force (>1.5 lbs or any preset values) will be applied on the stop ratchet, then stop ratchet is immediately locked, and then the moving strand as a whole is securely locked. Further tightening is prevented.