Necklace retaining clasp

A safety clasp for necklaces, bracelets and the like is provided with a leaf spring member having its ends canted outwardly so as to enter and engage receiving apertures formed in an outer member. Retaining rings are provided at each end of the separable clasp with the outer member having an outer tubular sleeve with an open and a closed end and with apertures formed intermediate its length. An inner member is slidable and rotatable within the outer member and carries the leaf spring by a spine member with said spring secured at its midlength at the inner end of the spine. Receiving means for the leaf spring is provided in and along the spine and a bias such as a coil spring is secured at the closed end and internal of the outer member to urge the inner member outwardly. A quarter-turn of this inner member is made to bring the ends of the leaf spring from in way of the apertures formed in the outer member.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
With reference to the field of art as established in and by the U.S. Patent 
Office this invention is believed to be found in the general class 
entitled, "Separable Fasteners" (Class 24) and in the subclass therein 
entitled, "Pivoted lock mounted on head" (Subclass 211P) and the subclass 
entitled, "Rigid socket" (Subclass 214). 
2. Description of the Prior Art 
Safety catches and clasps for necklaces have been the subject of many 
inventions. Most of these pertain to clasps that are designed to secure a 
hook-like end in a guard or a pin retaining sheath and/or cover. 
Quarter-turn lock and release apparatus are also well known. In 
Applicant's device there is provided a wing-type spring carried by and in 
an inner member of a safety spring catch. The other and outer sleeve 
portion has apertures for receiving and retaining the ends of the 
wing-type spring. A coil spring carried by and secured in this outer 
sleeve portion urges the other companion portion outwardly with the 
wing-type spring ends engaging the apertures. 
Quarter-turn and releasing fasteners are well known and the following show 
releasable fastening devices: 
U.S. Pat. No. 1,012,222 to Phinney on Dec. 19, 1911; 
U.S. Pat. No. 1,082,455 to Tilton on Dec. 23, 1913; 
U.S. Pat. No. 1,603,159 to Snyder on Oct. 12, 1926, and 
U.S. Pat. No. 2,271,500 to Rickenbach on Jan. 27, 1942. 
U.S. Pat. No. 1,056,452 to Remhilt as issued on Mar. 18, 1913 shows a 
slotted receiver and a spring actuated pronged companion member that is 
released by a quarter-turn action. This reference is quite satisfactory as 
a post binder but this patent does not teach or suggest Applicant's 
securing together with a constant spring pressure to retain the portions 
together until a deliberate compressing motion is made to close the 
wing-type members and then a quarter-turn is made to release the 
spring-type safety catch. 
SUMMARY OF THE INVENTION 
This invention may be summarized, at least in part, with reference to its 
object. It is an object of this invention to provide, and it does provide, 
a necklace retaining clasp. The terminal members of this clasp are easily 
placed within each other to close said clasp and in this secured condition 
are retained by a spring carried in an outer sheath member. The inner 
member is easily removed when this said inner member is moved against this 
spring which causes a wing-type spring carried by this second member to be 
inwardly moved and with a quarter-turn is caused to be released for 
separation of the clasp. 
In brief, this spring-type clasp for necklaces, bracelets and/or the like 
includes an outer member which is tubular in configuration and with this 
member having a closed end and an open end. The closed end also has 
secured thereto a connecting ring to which one end of the chain or string 
of the necklace is secured. This tubular member has opposed apertures 
provided near its open end. A coil spring is carried and secured within 
this member and at its closed end. A mating member is also generally 
tubular with a closed end to which there is also secured a connecting ring 
which may be secured to the other end of the chain or string. A collar may 
be secured to this second member to limit the inward movement of the 
second member within the first. A wing-type lock spring is secured within 
shaped recesses in this second member and the free ends are adapted to 
enter the apertures in the outer member and retain the clasp together. A 
pushing of the second member further within the outer member causes said 
wing-type spring to be withdrawn from the apertures in the outer member 
and with a quarter-turn allows the catch to be easily separated.

In the following description and in the claims various details are 
identified by specific names for convenience. These names are intended to 
be generic in their application. Corresponding reference characters refer 
to like members throughout the several figures of the drawing. 
DESCRIPTION OF THE PREFERRED EMBODIMENT 
Referring next to the drawing in which the spring-type safety catch is 
shown, both as components and in an assembled condition, it is to be noted 
that an outer tubular member 10 includes an open and a closed end. At the 
closed end there is secured, as by soldering or the like, a connecting 
ring 12. This ring is provided to enable the necklace chain or string to 
be secured to the clasp. Near the open end of the outer tubular member 10 
are formed opposed apertures 14 and 16. Within this member 10 and at its 
closed end there is secured and provided a coil spring 18. This spring is 
secured at its lower end as by solder, cement or the like so that the 
spring is not dislodged during and by use. This does not preclude using a 
resilient plug member such as rubber to provide the desired bias. 
The other and mating member includes a tubular portion 20 that is shown as 
having a notch 22 formed in its distal end. The other end is closed and 
another connecting ring 24 is secured to the outer end of this member. 
This mating member is a slide or slip fit within the tubular member 10. 
Preferably there is provided an outer collar member 26 attached to the 
member at the closed end thereof. This collar 26 provides a stop to limit 
the inward movement of the inner member within the outer member. This 
collar member may also be lightly knurled or decoratively roughened to 
assist in manipulation and turning. 
The tubular portion 20 below the collar 26 is preferably made or drawn from 
thin walled tubing and into the sidewall portion is formed two retaining 
grooves 28 and 30. Each groove terminates at the notch 22. A shaped leaf 
spring 32 is of a channel shape with the side portions of extended length 
and with the free ends slightly outwardly canted. This spring 32 is made 
with the side portions extending outwardly. The ends of the spring may be 
square cut or notched. A square cut is shown in FIG. 4A and a notch 
alternate construction is shown in FIG. 4B. Another spring configuration 
is shown in FIG. 4C. 
Alternate Outer Tubular Configuration of FIG. 2B 
Referring now to the drawing and FIG. 2B, it is to be noted that the outer 
member may have a tubular member 110 which may be a tubular portion cut to 
length and at the closed end there may be provided a drawn or shaped cap 
50 to which a ring 52 is secured. This cap may also provide the securing 
means for an end of spring 18. This cap 50 may also be used with a 
shouldered tube (FIG. 8A) having at least one stop shoulder 54 
longitudinally provided. The shoulder 54 is adapted to provide a guide for 
an end of a spring 18 as it is brought to an aperture 14 or 16. If the 
tube is an extrusion there may be two stop shoulders 54 provided. 
Leaf Spring of FIGS. 4A, B and C and 5A and B 
The simplest formed spring is shown in FIG. 4A and has square cut and 
outwardly canted ends as in FIGS. 4A, 5A and 7A. This spring is usually of 
a tempered steel ribbon which is bent to the configuration shown and 
identified as 32. The leaf spring may also be bent to provide a notch 56 
(FIGS. 4B. 5B and 7B) at the distal ends of the spring. This spring is 
identified as 132 (FIGS. 4B and 5C) and may also be used in the embodiment 
shown. In FIGS. 4C and 5C there is shown an alternate leaf spring 
configuration 232 in which the upper ends are retained in slots provided 
in a modified central portion of an inner member 120. As shown in FIG. 9 
it is to be noted this this spring may be secured at its midportion by a 
retaining collar or sleeve 60 which is slid onto the tubular portion 120 
and retained thereon by solder or cement. 
Leaf Spring as in FIGS. 7A and 7B 
The leaf spring as depicted may have a square cut end as in FIG. 7A or may 
have a V-shaped end as in FIG. 7B. No matter the configuration selected it 
is anticipated that the ends of the spring will enter and be retained by 
the apertures or cups formed in an outer member. 
Tubing Configuration as in FIGS. 8A and 8B 
The outer tubular member may be formed with internal shoulders that are 
engaged by spring 32 as it is turned to determine the desired alignment 
with the apertures 14 and 16. This is depicted in FIG. 8A in the drawing. 
It is also contemplated that apertures may not be used but cup shaped 
recesses 80 be formed in tubing 210 with shoulder stops that prevent 
uncoupling until pushing inward and a quarter turn made. Cups 80 are shown 
in FIG. 8B. This is not the preferred construction since an outer member 
210 is usually made of thin tubing and with abuse an outwardly extending 
cup portion may be deformed to the extent that the securing of the clasp 
may be less than positive. 
Alternate Construction of Inner Member as seen in FIG. 9 
Referring next and finally to FIG. 9, there is depicted a center spine 
portion of an inner member which includes an extrusion identified as 70 
and having flats 72 and 74. As depicted, this spine is a solid extrusion 
and the flats thereon accommodate the leaf spring as it is cammed inwardly 
during insertion. This extrusion may be hollow and may have shallow 
grooves longitudinally disposed in an extrusion such as seen in FIG. 6 
rather than flats. The manufacturer of the clasp can and may select the 
desired configuration and size. An end member 76, much like that shown in 
FIG. 2B provides the end closure and retainer for the ring member. The 
spine is shown with flats but a spine having the desired clearance for a 
leaf spring may be provided with only a smaller diameter as long as the 
leaf spring is secured at its mid-point. 
Use and Operation 
The spring-type safety clasp is quite fool proof and easy to manipulate. 
The chain or string of the necklace and the like is secured at each end to 
connecting rings 12 and 24, usually by auxiliary links that may be opened 
and closed by the jeweler attaching this clasp to the necklace. The wearer 
of the necklace inserts the tubular portion 20 into the outer member 10 
and continues insertion until resistance by coil spring 18 is encountered. 
The members are rotated one with the other until the outer ends of the 
leaf spring 32 enters and is retained by apertures 14 and 16. Spring 18 
urges the inner member 20 outwardly to provide bias for retaining the 
clasp in a secured position. A disconnect of the clasp is easily achieved 
by the user with a simple inward displacement of member 20 in outer member 
10 until collar 26 provides a stop. The user then makes a quarter-turn 
which moves the ends of spring 32 from alignment with apertures 14 and 16 
and the clasp is then readily disengaged. 
The outer tubular portion may be formed with an internal longitudinal 
shoulder guide. As depicted in FIG. 8A an outer tubular member 110 is 
formed with at least one longitudinal shoulder guide 54. This shoulder 
guide is aligned with an aperture so that the shaped spring 32 is easily 
guided into a receiving aperture. Preferably the spring 32 has a square 
cut at the free ends thereof so that these ends are disposed to enter and 
engage the apertures formed in the outer tubular member. Alternately, the 
shaped leaf spring may have its ends formed with notches or V-shapes 56 so 
that the projecting portion of said ends will enter and engage an aperture 
formed in the outer member. The V-shaped ends are shown in FIGS. 4B, 5B 
and 7B and are provided in an alternate leaf spring 132. 
It is to be further noted that a cap portion 50 (FIG. 2B) may be used to 
close the end of the outer tube to provide a decorative and manipulative 
assist. The connecting rings are shown as generally circular but may be 
made in any desired configuration and need not be fixed but may be pivoted 
or swivel mounted. The ends of the leaf spring 32 or 132 are configured to 
enter and engage the apertures 14 and 16 and are maintained in this 
position by spring 18 which may be a compression coil spring or may be a 
resilient member. Gold or similar plating to prevent tarnish is provided 
to this clasp. Plating is suggested since the cost of precious metals is 
very high but this is not to preclude their use. The midportion of spring 
32, 132 or 232 are shown as flattened to be retained in the notch 22 by a 
crimp action but solder or other adhesive means is contemplated. The use 
of a sleeve and the possible elimination of the notch 22 is not overlooked 
in this application since the production configuration of the components 
of the clasp will be selected to conform with the available materials 
and/or production levels. Dies, assembly tools, etc. are cost 
considerations to be evaluated and balanced in the production of the 
clasp. 
It is to be noted that the above described clasp may have an outer tubular 
member 10 that is not completely closed at its retaining end but is 
sufficiently closed to provide retention means for the spring 18 and 
provide a retaining means for the connecting ring 12. In this regard the 
tubular member may be made of sheet metal with the formed apertures and 
shoulders then rolled into a tube and then with the closed end having an 
attached end cap with the ring attached thereto as in FIG. 2B. The tension 
lock spring 32 may be of generally channel shape with a short more-or-less 
straight portion or a curved midportion may be provided. The configuration 
is merely a matter of choice as long as the spring is secured to the inner 
member in a preestablished orientation. In a mounted condition the two 
extending ends are disposed or canted outwardly so as to extend and engage 
the apertures or cups formed in the outer member. The apertures 14 and 16 
are shown as rectangular but may be of any configuration as long as the 
ends of spring 32 enter and engage said apertures during retentive 
positioning. The formed apertures or cups are disengaged by the ends of 
spring 32 when the clasp is closed against spring 18 and a quarter turn is 
achieved when and as the ends of the spring are within the outer tubular 
member. It is to be noted that the outward flare or disposition of the 
distal or free ends of spring 32, 132 or 232 are guided inwardly to a 
position within the wall of the outer tube when the member 20 is pushed 
inwardly to the collar stop. This inward motion is readily ascertained in 
FIG. 2A to cause the ends of said springs to be cammed inwardly of the 
apertures. 
It is, of course, realized that the clasp may be made substantially of 
plastic and use only metal for the spring 32. The inner member may have 
grooves 28 and 30 formed as flats or grooves in an extrusion as in FIG. 9. 
The spring 32 may be held in place by an attached collar, said collar held 
in place by solder or cement. The grooves or flats are used to provide a 
guideway for the spring. The spring 32, 132 or 232 may be made from flat 
stock or may have thicker ends. Whatever the configuration, the springs 
32, 132 or 232 lay within the outer member when inserted and the outward 
flare or cant of said spring ends is guided with and by the tubular 
confines. When tubular portion 20 is inserted to engage spring 18 the 
resistance is felt and the turning to bring the ends of the spring in way 
of the apertures 14 and 16 or cups 80 for securing the clasp is easily 
achieved. The placement of the opposed apertures 14 and 16 in the outer 
member 10 is merely a matter of choice as any intermediate position may be 
selected. Preferably the apertures are equidistant from an end but this is 
only a matter of convenience of use and unequal spacing is also 
contemplated. It is only important that about a quarter turn of the 
members to each other be achievable when moved to substantially an inward 
condition whereat the spring 32 is cammed inwardly from the apertures 14 
and 16 to allow said rotation. 
Terms such as "left", "right", "up", "down", "bottom", "top", "front", 
"back", "in", "out" and the like are applicable to the embodiments shown 
and described in conjunction with the drawing. These terms are merely for 
the purposes of description and do not necessarily apply to the position 
in which the necklace retaining clasp may be constructed or used. 
While a particular embodiment of the clasp and alternate embodiments have 
been shown and described it is to be understood the invention is not 
limited thereto and protection is sought to the broadest extent the prior 
art allows.