Identification bracelet and clasp construction therefor

A patient identification bracelet is composed of a flexible strap and a clasp, the clasp being formed of thermoplastic material and having a base member fixed to one end portion of the strap and a hinged cover member projecting laterally from the strap when the clasp is open. Holding elements project from at least one of the opposable surfaces of the cover and base member for engaging and holding the opposite end portion of the strap when the clasp is closed, and a mating post and socket are provided for locking the clasp in its closed condition. The post and socket are constructed so that the clasp, if forced open, cannot be reclosed. A relatively weak portion of the strap, located between the end portion of the strap that is fixed to the clasp and the identification-receiving portion of the strap, and also located between the base and cover members when the clasp is closed, defines a break-away zone for the strap when pulling forces of predetermined magnitude are applied thereto.

SUMMARY OF THE INVENTION 
Patient identification bracelets of a variety of constructions and designs 
are known and in widespread use. Nevertheless, a need continues for a 
disposable identification bracelet that is of relatively low cost 
construction and which at the same time is easily operated, durable and 
reliable in use, and provided with a closure system that is secure and 
tamperproof. The term "tamper-proof" is here used to mean if the closure 
should be forced open after the bracelet has been attached to a patient's 
limb, it cannot be reclosed and the bracelet cannot be reused. Also, the 
circumference of the bracelet when secured cannot be adjusted (i.e., 
enlarged), thus rendering the bracelet non-transferable. 
The non-reclosable identification bracelet of this invention takes the form 
of an elongated strap of tough, flexible and substantially non-stretchable 
sheet material having a clasp for securing the ends of the strap together 
after it has been placed about a patient's wrist (or ankle). The clasp is 
formed of thermoplastic material and has base and cover members joined by 
an integral hinge portion. The base member is fixed to one end portion of 
the strap so that the cover member projects laterally from one side edge 
of the strap when the clasp is open and is foldable into a closed position 
over the base member for clamping the opposite end of the strap after the 
strap has been wrapped about a wearer's limb. Holding or gripping means 
are provided along at least one (preferably both) of the opposable 
surfaces of the base and cover members for securely engaging the opposite 
end portion of the strap when the clasp is closed. Locking means are also 
provided by the clasp for securing the two members in closed condition. 
The locking means takes the form of a post provided by one of the members 
and a socket provided by the other member. The post has head and stem 
portions, with the stem portion including a plurality of 
radially-extending and circumferentially-spaced ribs that connect the head 
to the member from which the post projects. A plurality of 
outwardly-facing recesses are located between the ribs, and such recesses 
receive a plurality of locking blades or fins formed in the wall of the 
socket when the post and socket are mated together. Since the ribs taken 
together are of a total cross section in their areas of connection to the 
(cover) member less than that of the combined cross sectional area of the 
locking blades or fins, a force of magnitude sufficient to pry the base 
and cover members apart after the clasp has been closed will have the 
effect of tearing or detaching the ribs, thereby destroying the post and 
rendering the clasp non-reclosable. 
The holding or gripping means provided by the opposable surfaces of the 
clasp's base and cover members may take the form of a multiplicity of 
teeth projecting from one or both of the members. Preferably such teeth 
are provided along the opposable surfaces of both members and are 
generally pyramidal in shape, with the teeth of the respective members 
being offset from each other. The teeth of one of the members may have 
flat faces that are generally perpendicular to that member and face in one 
direction longitudinally of the strap, whereas the teeth of the other 
member may be provided with flat faces also perpendicular to such other 
member but facing in an opposite direction longitudinally of the strap. 
In another embodiment, the holding or gripping means may take the form of 
ridges projecting from at least one, and preferably both, of the base and 
cover members. Such ridges extend generally transversely with the ridges 
of the respective members being offset with respect to each other. The 
ridges may have beveled edges and may extend perpendicular to the length 
of the strap. In a preferred construction, the transverse ridges are 
chevron-shaped. The chevron-shaped ridges may all point in the same 
direction longitudinally with respect to the strap or, in another 
embodiment of the invention, may be arranged in opposing sets to provide a 
generally diamond-shaped pattern of ridges for each of the hinged members 
of the clasp. 
The first end portion of the strap that is fixed to the clasp has a 
relatively weak portion defined by an opening in the strap that is located 
between the attachment between the strap and clasp and the 
identification-receiving portion of the strap. The opening is thus located 
between the base and cover members when the clasp is closed and preferably 
allows the teeth or ridges of the base member to contact the opposite end 
portion of the strap when the bracelet is fastened about a wearer's wrist 
or ankle of particular importance is the fact that the opening or cutout 
reduces the cross-sectional area of the strap and thereby defines a 
transverse zone of weakness for preferential tearing of the strap when a 
pulling force exceeding a predetermined maximum is applied to the strap. 
Other features, objects, and advantages of the invention will become 
apparent from the specification and drawings.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
Referring to FIGS. 1-10 of the drawings, the numeral 10 generally 
designates a patient identification bracelet comprising a strap or band 11 
and a clasp 12. The elongate strap has first and second end portions 13 
and 14, respectively, and generally parallel longitudinal side edges 15. 
Preferably, the strap has a relatively wide intermediate portion 11a for 
receiving printed, typed, or handwritten indicia setting forth vital 
information concerning the patient. The strap may be formed of any tough, 
flexible and substantially non-stretchable sheet material providing an 
outer surface capable of receiving indicia. A variety of such materials 
having these characteristics are well known in the art. One such material 
believed to be particularly effective is a trilaminate of synthetic paper 
(Kindura), polyester and textured polyethylene, but other materials having 
similar properties may be used. 
The clasp 12 is formed in one piece from a tough and relatively stiff but 
flexible thermoplastic material such as nylon or a polyolefin (e.g., 
polypropylene). The clasp includes a base member 16 and a cover member 17 
joined together by an integral hinge portion 18. As shown most clearly in 
FIGS. 1 and 6, the base member is staked or otherwise permanently secured 
to the first end portion 13 of the strap. For purposes of such attachment, 
the base portion includes a ledge or projection 19 that extends 
longitudinally with respect to strap 11 and is provided with integral 
stakes or pins 20 that project through openings in the strap to secure the 
strap and base member together. After being inserted into the openings of 
the strap, the stakes may be flattened (by heat and pressure) at their 
free ends to permanently anchor the parts together. 
The clasp 12 is secured to end portion 13 of the strap in a direction that 
extends transversely of the strap, with the hinge portion 18 parallel with 
the edges 15 of the strap and with the cover member 17 normally projecting 
laterally away from the strap, as shown in FIG. 6. (In FIG. 1, the cover 
member is shown in partially raised condition.) In use of the bracelet, 
the strap is wrapped loosely about a patient's wrist and free end portion 
14 is drawn over the end portion 13 affixed to clasp 12. The cover member 
of the clasp is then closed to join the ends of the strap together. 
Locking means for anchoring the cover member in closed condition takes the 
form of post 21 and socket 22. As shown most clearly in FIG. 6, the socket 
is provided by the base member along the opposite side of the strap 11 
from hinge 18. While the base member is shown with only one such socket, 
and the cover member with only one post 21, it is to be understood that 
two such sockets and posts may be provided by the respective members, if 
desired. In any event, the socket(s) and post(s) are arranged to be 
brought into mating relation when the cover member is folded along hinge 
18 into closed condition. 
Post 21 includes a head portion 23 and a stem portion 24. A plurality of 
ribs 25 (four, in the embodiment illustrated) radiate outwardly from the 
stem and join the stem and head to the remainder of the cover member 17. 
As a result, the stem 24 and head 23 are not directly connected to the 
cover member. The ribs 25, which are integral with the post and cover 
member, serve as bridging connections, with arcuate spaces 26 between 
adjacent rib connections (FIGS. 6, 3). The strength of the connection 
between the post 21 and the cover member 17 therefore turns on the 
strength of the ribs and, specifically, the cross section of such ribs and 
their points of connection to the remainder of the cover member of which 
they are an integral part. 
Socket 22 includes a generally cylindrical opening 27 in which is located a 
generally frusto conical arrangement of downwardly and inwardly sloping 
wall segments 28. The number of such segments corresponds to the number of 
recesses 26 provided by the post, and the segments 28 are positioned and 
arranged to be received within such recesses when the post and socket are 
fitted together. The segments 28 function as flexible blades or fins which 
bend outwardly to accommodate the head portion of the post as it is 
inserted into the socket and, once the head portion 22 has cleared them, 
the blades or fins 28 snap into recesses 26 to lock the base and cover 
members together (FIG. 9). 
The cross sectional area of the integral connection between the blades or 
fins 28 and the remainder of base member 16 is substantially greater than 
the cross sectional area of the connection between ribs 25 and cover 
member 17. Therefore, once the cover has been closed as shown in FIG. 9, 
the post is securely retained in the socket and forces tending to pry the 
base and cover members apart only cause the blades or fins to seat more 
securely in the recesses 26 and bear more tightly against head 21. If the 
prying force is of sufficient magnitude to tear the clasp, such tearing 
occurs between the ribs 25 and their connection to cover member 17 (FIG. 
10). Since detachment of the post from the cover member destroys the 
locking means and, more specifically, visually, tactilely, and 
mechanically eliminates one locking element of the pair, it is readily 
apparent when detachment of a bracelet has resulted from the application 
of such forces and equally apparent that reclosing of the band is 
impossible. 
In the embodiment of FIGS. 1-10, holding or gripping means are provided by 
the clasp to prevent longitudinal sliding movement of the strap when the 
clasp is closed. Such gripping means takes the form of a multiplicity of 
teeth 30 and 31 projecting from the opposable surfaces 17a and 16a of the 
cover and base members 17 and 16, respectively. The teeth 30 of the cover 
member frictionally engage the upper surface of end portion 14 of the 
strap, whereas teeth 31 project upwardly through window opening 32 in the 
end portion 13 of the strap to engage the undersurface of end portion 14 
when the strap has been fitted about a wearer's wrist and clasp 12 is 
closed. 
It will be noted from FIGS. 4-6 that each tooth is generally pyramidal in 
shape with three faces, one of which 30a, 31a is normal or perpendicular 
to the plane of the surface from which the tooth projects. It will also be 
noted that perpendicular faces for the teeth of one set face in one 
longitudinal direction relative to the strap while the perpendicular faces 
of the teeth of the other set face in the opposite longitudinal direction. 
Hence, the two sets of teeth, taken together, engage opposite sides of 
strap end portion 14 and secure that end portion against sliding movement 
in either direction. 
The teeth 30 and 31 of each set are offset from each other, causing an 
undulation in the engaged end portion of the strap 14 when the clasp is 
closed. Such deformation of the strap, combined with the frictional 
engagement or biting action of the teeth against the strap, effectively 
lock end portion 14 of the strap in place. 
While two sets of teeth are shown in the drawings, sufficient locking 
action might be achieved with only one set of teeth, such as the 
multiplicity of teeth 30 provided by cover member 17. Two sets of teeth 
are shown in the preferred embodiment so that if a strong pulling force is 
applied in an effort to enlarge and remove a bracelet, the gripping force 
that prevents such sliding action will equal or exceed the tensile 
strength of the strap itself. 
The embodiment of FIGS. 11-13 is the same as the one already described 
except that the holding or gripping means takes the form of a plurality of 
spaced ridges 40 and 41 which project from the opposable surfaces 17a' and 
16a' of cover member 17' and base member 16', respectively. The ridges 
extend transversely with respect to the strap 11' and, if desired, end 
portion 13' of the strap may be provided with a window 32' to expose 
ridges 41 for contact with the underside of the strap's other end portion 
when the bracelet is in place and cover member 17' is ready to be closed. 
It is to be noted from FIG. 12 that ridges 40 and 41 of the two sets are 
arranged in offset parallel relation. Thus, when the clasp is closed, the 
ridges 41 of the base member 16' extend between the parallel ridges 40 of 
cover member 17'. Also, referring to FIGS. 14 and 15, it will be seen that 
teeth 40 and 41 have beveled edges or end surfaces 40a and 41a, 
respectively. The beveled surfaces for one set of teeth 41 provided by 
base member 16' angle in one longitudinal direction relative to strap 11', 
whereas the beveled end surfaces 40a of teeth 40 of cover member 17' are 
angled in the opposite longitudinal direction. 
As with the gripping means of the previously-described embodiment, ridges 
40 and 41 restrain sliding movement of the clamped portion of a strap when 
the clasp is closed. Again, the provision of sets of offsetting ridges on 
both members 16' and 17' provides security against sliding movement of the 
strap and causes the portion of the strap between such ridges to assume a 
zigzag or undulating configuration, thereby reducing the possibility of 
sliding movement of the strap. 
A third embodiment of the bracelet is depicted in FIGS. 16-18 and differs 
from the previous embodiments in features relating to the holding or 
gripping means of the clasp 112 and, in particular, the strap 111 and the 
way it is connected to the clasp. As in previous embodiments, the strap 
includes a first end portion 113, a second end portion 114, an 
intermediate portion (of greater width) for receiving patient information, 
and an opening or cutout 132 located in end portion 113 overlying the base 
member 116 of the clasp. In contrast to the previously-described 
embodiments, however, end portion 113 of the strap is fixed to a 
projection or ledge 119 located on the opposite or far side of the clip's 
base member 116 opening 132 is therefore disposed between the area of 
fixation of the strap's end portion 113 and the clip 112, on one hand, and 
the strap's intermediate indicia-receiving portion 111a, on the other. 
Because of the opening, the cross-sectional area of the strap, and hence 
the strength of the strap, are reduced in that area. The tear strength of 
the strap may therefore be adjusted to a predetermined level by varying 
the size of the opening for the particular strap material selected. When 
the bracelet is worn, the apertured portion of the strap disposed within 
the clasp constitutes a portion of predetermined weakness for preferential 
tearing of the strap when a pulling or tearing force of selected magnitude 
is reached. This allows the band to break or tear apart at a safe force 
level which not only prevents the possibility of the band from slipping 
within the clip but also reduces the chances of injury to a patient. 
Since opening 132 overlies the gripping means provided by base member 117, 
it also allows direct contact between such gripping means and the second 
end portion 114 of the strap when the bracelet is fitted upon a patient. 
In this respect, opening 132 provides an advantage provided by 
previously-described embodiments. 
The gripping means takes the form of a plurality of chevron-shaped ridges 
or ribs 140 and 141 which project from opposable surfaces 117a and 116a of 
the cover member 117 and base member 116, respectively. The chevron-shaped 
or V-shaped ridges all point in the same direction (preferably towards the 
distal second end 114 of the strap when the bracelet is in planar 
condition as shown in FIG. 16) and the spaced ridges of the respective 
members are offset so that one set of ridges 140 fits between the other 
set of ridges 141 when the clasp is closed. It will also be noted that the 
ridges are beveled with the beveled surfaces preferably facing away from 
end portion 114 of the strap when the bracelet is in the flat condition 
illustrated in FIG. 16. 
In other respects, the bracelet of FIGS. 16-18 is similar to previous 
embodiments. In particular, the locking means for anchoring the cover 
member in closed condition takes the form of post 21 and socket 22 as 
previously shown and described. 
The embodiment of FIGS. 19-21 is identical to that of FIGS. 16-18 except 
for the holding or gripping means provided by the base member 216 and 
cover member 217. Each member has its chevron-shaped ridges 240 and 241 
arranged in opposition, forming a generally diamond-shaped pattern. Again, 
the ridges are beveled and those of one member are offset with respect to 
those of the other member so that there is an interfitting relationship 
between the two sets when the clasp is closed. 
While in the foregoing, we have disclosed embodiments of the invention in 
considerable detail for purposes of illustration, it will be understood by 
those skilled in the art that many of these details may be varied without 
departing from the spirit and scope of the invention.