U.S. patent number 3,638,285 [Application Number 05/026,577] was granted by the patent office on 1972-02-01 for two-part lock button.
Invention is credited to Jose Humberto Sanchez Giraldez.
United States Patent |
3,638,285 |
Sanchez Giraldez |
February 1, 1972 |
TWO-PART LOCK BUTTON
Abstract
A two-part lock button consists of a male and a female button
half and the male part comprises a locking bolt member which is
provided with one or several locking grooves and can be inserted
into an opening in the female part. The female button half
comprises one pair or several pairs of retaining discs which upon
insertion of the male button half into the female button half will
come into engagement with the one or several locking grooves of the
male part thus firmly locking together these two parts. Release of
the button halves can be effected by means of a mechanical or
magnetic key.
Inventors: |
Sanchez Giraldez; Jose Humberto
(Hamburg, DT) |
Family
ID: |
27182106 |
Appl.
No.: |
05/026,577 |
Filed: |
April 8, 1970 |
Foreign Application Priority Data
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Aug 21, 1969 [DT] |
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P 19 42 535.5 |
Mar 3, 1970 [DT] |
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P 20 09 760.3 |
Jan 24, 1970 [DT] |
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P 20 03 164.5 |
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Current U.S.
Class: |
24/108;
24/673 |
Current CPC
Class: |
F16B
12/26 (20130101); F16B 21/078 (20130101); Y10T
24/45832 (20150115); Y10T 24/366 (20150115) |
Current International
Class: |
A44B
1/00 (20060101); A44B 1/34 (20060101); F16B
12/00 (20060101); F16B 21/07 (20060101); F16B
12/26 (20060101); F16B 21/00 (20060101); A44b
001/38 (); A44b 017/00 () |
Field of
Search: |
;24/108,216,217,23M
;292/251.5 ;70/276,413 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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67,616 |
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Jul 1892 |
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DD |
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8,720 |
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Apr 1897 |
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GB |
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509,649 |
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Jul 1939 |
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GB |
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Primary Examiner: Gilliam; Paul R.
Claims
I claim:
1. A two-part lock button assembly, comprising a first button half,
a second button half releasably engageable with said first button
half, and means for releasing said second button half from
engagement with said first button half, said first button half
comprising an axially extending casing, said casing having a first
surface disposed transversely of its axis with a centrally disposed
opening therein and a second surface disposed transversely of said
casing axis and being spaced from said first surface, a pair of
retaining disks mounted within said casing between the first and
second surfaces and extending transversely of said casing axis,
said disks being arranged in substantially coplanar relationship,
and each said disk having a retaining edge surface located on an
opposite side of said casing axis and in facing and spaced
relationship with the retaining edge surface on the other said
disk, spring means within said casing for biasing the retaining
edge surfaces of said retaining disks toward the first surface of
said casing, support means within said casing for said retaining
disks including abutment means on the first surface side of said
retaining disks against which said disks are biased by said spring
means, and bearing support means on the second surface side of said
retaining disks about which said retaining disks are tiltably
displaceable when the biasing action of said spring means is
overcome, said second button half comprising an elongated bolt and
a support member secured to and extending transversely of one end
of said bolt, said bolt having a circumferentially extending
shoulder formed inwardly into said bolt adjacent its end opposite
the end connected to said support member and the shoulder being
faced toward said support member, and said means for releasing said
second button half from engagement with said first button half
comprises a member positionable adjacent the second surface of said
casing for tiltably displacing the retaining edge surfaces of said
retaining disks toward the second surface of said casing against
the biasing action of said spring means for releasing said second
button half so that it can be withdrawn through the opening in the
first surface on the opposite end of said casing.
2. A two-part lock button assembly, as set forth in claim 1,
characterized in that said retaining disks being formed of magnetic
material and said means for releasing said second button half
comprising a magnetic plate positionable against the second surface
of said casing in register with the retaining edge surfaces of said
retaining disks for attracting said retaining disks toward said
second surface and tiltably displacing them for displacing the
retaining edge surfaces of said retaining disks from engagement
with the shoulder on said bolt.
3. A two-part lock button assembly, as set forth in claim 1,
characterized in that a first rigid body having an opening therein
with said casing embedded within the opening, a second rigid body
having an opening therein and said support member being embedded
within the opening with said bolt extending from said second rigid
body, said second rigid body having a surface thereon through which
said bolt extends arranged to be positioned in contacting
engagement with a surface on said first rigid body having an
opening therein aligned with the opening in the first surface of
said casing, said first rigid body being open for affording access
to the second surface of said casing embedded therein so that said
means for releasing said second button half can be positioned
adjacent the second surface of said casing for tiltably displacing
the retaining edge surfaces of said retaining disks within said
casing, a spring member being positioned within one of said first
and second rigid bodies for biasing the one of said casing and said
second button half within said rigid body containing said spring
member in the axial direction of said casing in the direction of
the second surface of said casing.
4. A two-part lock button assembly, as set forth in claim 1,
characterized in that said bolt has a plurality of
circumferentially extending axially spaced grooves in its surface
forming a plurality of said shoulders which engage the retaining
edge surfaces on said retaining disks, the shoulder in one of said
grooves being selectively engageable with said retaining disks, the
second surface of said casing having an opening therethrough in
axial alignment with the opening through the first surface thereof,
and said means for releasing said second button half comprising a
magnetic plate member having a centrally disposed opening
therethrough and the opening being arranged to be placed in
register with the opening in the second surface of said casing when
said magnetic plate member is placed against the second surface so
that said retaining disks can be tiltably displaced with said bolt
being positionable through the opening in the second surface of
said casing and in said magnetic plate member in dependence on the
extent to which said bolt is inserted into said casing for
engagement between the retaining edge surfaces of its retaining
disks and one of said grooves on said bolt.
5. A two-part lock button assembly, as set forth in claim 1, and
comprising an axially extending guide sleeve, a plurality of
axially aligned said casings forming said first button halves being
positioned within said guide sleeve in coaxial relationship
therewith, a pair of said retaining disks positioned within each
said casing, a spring positioned within said guide sleeve for
biasing said casings therein against axial movement within said
guide sleeve, said guide sleeve comprising a plate extending
transversely across one end thereof and having a centrally disposed
opening for receiving said bolt and an inwardly directed flange
extending transversely inwardly from the opposite end of said
sleeve for retaining said casings forming said first button halves
therein against the action of said spring.
6. A two-part lock button assembly, as set forth in claim 5,
characterized in that said abutment means comprising annular
sections of foamlike plastic, each positioned within one of said
casings and extending in the axial direction thereof, said annular
sections being positioned for supporting the radially outer
portions of said retaining disks relative to the axes of said
casings, and guide rods extending axially through said casings
positioned within said guide sleeve for interconnecting said
retaining disks therein for displacing each of said disks and
thereby releasing the retaining edge surfaces of said disks from
said bolt when said means for releasing said button half is
positioned against the second surface of said casing adjacent the
end of said guide sleeve having the inwardly directed flange.
7. A two-part lock button assembly, as set forth in claim 2,
characterized in that said magnetic plate for releasing the
retaining edge surfaces of said retaining disks from engagement
with said bolt comprises an electromagnet arranged adjacent the
second surface of said casing for tiltably displacing said
retaining disks upon its energization.
Description
This invention relates to a two-part lock button comprising a pair
of preferably semicircular retaining disks arranged within a first
button half in the shape of a casing whereby these retaining disks
are adapted to engage a locking groove provided on a bolt of
another button half which bolt is adapted to be centrally inserted
into the first button half and the retaining disks are releasable
from engagement with the locking groove by means of a key. Lock
buttons of this type are employed for various purposes for which a
fastening means consisting of two halves such as a press fastener
is required which prevents an inadvertent or unauthorized
disengagement of the two button halves.
In an already known two-part lock button of this type the two
semicircular retaining disks are mounted slidably in opposite
directions and vertically to the button axis in the casing of the
one button half. Each of the retaining disks is exposed to one of
two oppositely directed radial restoring forces provided by rubber
abutments arranged between the circumference of each disk and the
adjacent sidewall of the casing. By inserting a key having two
parallel and rigidly connected bolts through openings in the casing
of the one button half and through openings which are arranged in
each of the two retaining disks behind these first-mentioned
openings, the retaining disks may be wedged apart in opposite
directions, thus disengaging these disks from the locking groove in
the bolt of the other button half, allowing to withdraw the bolt
carrying button half from the casing button half. Since with such
an arrangement the key movement in the button axis must be
translated into two oppositely directed movements of the retaining
disks vertically to the button axis the force required for
disengaging this known type of lock button is relatively large. For
handling the button it is furthermore unfavorable that for
disengaging the lock button a pressure must be exerted on the
button in the direction of the button axis and simultaneously or
immediately thereafter a pulling force must be applied in the same
direction to the bolt carrying button half.
It is therefore a general object of the present invention to
improve a two-part lock button of the above-mentioned type so that
the force which must be applied to the retaining disks for
disengaging the button may be directed in the direction of the
button axis and opposite to the direction of the pulling force
applied to the bolt carrying button half when pulling this bolt out
of the casing in order to thus facilitate handling of the button,
to reduce the force required and to provide the possibility of
employing keys which operate according to differing principles.
The invention proposes to employ a key in the form of a resilient,
two-legged hooked clamp having two leg portions provided with hooks
which may be inserted through openings in the casing of the one
button half and through retaining disk openings arranged behind
these casing openings so that as a result of the resiliency of the
hooked clamp these hook portions engage these retaining disks from
their opposite sides and tilt these disks against the force of the
return spring upon withdrawal of the hooked clamp.
Additionally or alternatively the key may be provided in the form
of a magnetic plate bearing a handle whereby this magnetic plate is
adapted to exert a force of attraction onto the retaining disks
which are of a magnetic material when the magnetic plate key is
brought into registration with a freely accessible plane surface
provided on the casing of the first button half so as to tilt the
retaining disks against the axially directed force of the return
spring.
The invention furthermore proposes a particularly advantageous
application of a two-part lock button of this type wherein the
button serves as a coupling member between rigid bodies which may
be elements of a collapsible model, a box, furniture or toys.
Toward this purpose the two button halves are mounted in rigid
bodies which may be coupled to each other in such a manner that the
button half forming a casing for the retaining disks is accessible
to the key at a surface located on the one body opposite to a
surface forming the contact surface of this one body with the other
of these two rigid bodies and wherein the bolt provided at the
other button half protrudes from the corresponding contact surface
of the other body. This arrangement allows to simply assemble the
two rigid bodies at their contact surfaces so that the protruding
bolt penetrates into the opening of the other button half resulting
in the engagement of the retaining disks with the locking groove of
the bolt, thereby rigidly connecting the two bodies.
Another improvement provided by the present invention is that one
of the two button halves is mounted in one of the rigid bodies and
is guided therein for axial movement against the force of a spring
arranged within a sleeve-shaped body. If this movably mounted
button half is the casing-shaped button half then this will allow
to not automatically effect the coupling by inserting the two rigid
bodies but only by pushing the casing-shaped button half with a
finger or by means of another determined effort towards the bolt.
If the movable button half consists of the button carrying button
half then it is possible to push the bolt in the decoupled
condition into the rigid body which is provided with the button
half carrying the bolt thus reducing the danger of injuries.
In a preferred embodiment according to a further proposal of the
present invention one of the rigid bodies in which is mounted the
button half forming a casing for the retaining disks comprises a
wall portion of a collapsible hollow body whereas the other rigid
body comprises a supporting or connecting element for two or
several adjacent wall portions of the hollow body arranged on the
interior of the hollow body.
According to a further feature of the invention the locking bolt of
the second button half comprises several spaced locking grooves,
the casing of the first button half is provided with an upper cover
plate having an aperture and the magnetic key is centrally provided
with an aperture, these apertures adapted for passing through the
locking bolt of the second button half. This arrangement allows to
firmly couple the two button halves since the button half with the
retaining disks may be pushed so far into the other button half
until the retaining disks engage one of the locking grooves of the
locking bolt. This arrangement allows moreover connecting the two
button halves if a larger clearance must be maintained between the
two button halves. By selectively depressing the button half with
the retaining disks into one of the several locking grooves on the
locking bolt several different clearances may be accommodated
without reducing the firmness of the lock connection.
A further improvement according to the present invention is that
several button halves including retaining disks are arranged on top
of each other in the form of a button half assembly, the button
halves being jointly mounted in a guide sleeve for axial movement
against the force of a spring which engages a bottom plate
connected to the guide sleeve, the guide sleeve partially
overlapping the upper of the button halves, and the bottom plate
being provided with a central aperture for passing through the
locking bolt of the second button half. In this arrangement the
tiltably mounted locking disks are connected by means of guide rods
mounted for axial movement in the casings of the button halves so
that upon application of the key in the from of a magnet to the
freely accessible back side of the casing-shaped button half the
engagement may be released, i.e., the retaining disks of the upper
button half may be moved out of the locking groove of the locking
bolt on the other button half. This movement is transmitted to the
retaining disks of the other button halves by means of the
connecting rods thus allowing to separate the two parts.
In the following the invention will be described by means of
several preferred embodiments which are shown in the accompanying
drawings. Similar reference numerals in the various figures of the
drawings are intended to indicate like or similar parts.
FIG. 1 is a lateral-elevational view of one button half comprising
a plate and a bolt with a locking groove;
FIG. 2 is a vertical cross-sectional view of the corresponding
other button half comprising the retaining disks;
FIG. 3 is a lateral-elevational view of a key in the form of a
two-legged hooked clamp, the condition for inserting the key being
shown in phantom lines;
FIG. 4 is a lateral-elevational view of another key in the form of
a magnetic plate;
FIG. 5 is a cross-sectional view of a casing-shaped button half
comprising the retaining disks whereby the button half is movably
mounted in a sleeve arranged within a rigid body;
FIG. 6 shows a bolt carrying button half which is mounted in a
rigid body;
FIG. 7 shows a key for unlocking the button half, the key having
the form of a permanent magnet which is shaped like an annular disk
or a circular cylinder;
FIG. 8 is an elevational view of the casing-shaped button half
which is mounted in a rigid body;
FIG. 9 shows the bolt carrying button half mounted in a rigid body
and slidable within a sleeve whereby sliding movement is prevented
by a setscrew;
FIG. 10 illustrates an application of the invention to a box-shaped
hollow body comprising a plurality of detachable wall portions into
which are built-in lock buttons according to the invention, these
lock buttons being held by supporting or connecting elements (not
shown) provided with built-in button halves and arranged on the
interior of the box;
FIG. 11 is a cross section through the box of FIG. 10 and shows
schematically the attachment of the wall portions and the
supporting or connecting elements by means of two-part lock buttons
according to the invention;
FIG. 12 illustrates partly in cross section and partly in elevation
a button half, together with a magnetic key arranged on top of the
button half and another second button half arranged below the
first-mentioned button half, as well as a locking bolt having
several locking grooves;
FIG. 13 is a cross-sectional view along the line II--II of FIG. 12;
and
FIG. 14 is a vertical cross-sectional view of several button halves
including retaining disks and arranged on top of each other.
Referring to FIG. 1 the one button half comprises in a conventional
manner a plate such as the circular plate 1 carrying a center
locking bolt 2 having a locking groove 3.
The other button half comprises a two-shell casing 4, 5 and may
likewise have the shape of a circular disk (FIG. 2). Reference
numeral 6 indicates rivets by which the two casing shells are
attached to each other. Alternatively the casing shells may also be
bonded at their parting line. The rivets 6 penetrate with ample
clearance into an opening 7 in the preferably semicircular
retaining disks 8, 9. These retaining disks 8, 9 are tiltably
mounted on stud-shaped bearings 10, 11 and are biased downwardly by
a helical spring 12 acting in the direction of the button axis and
urging the disks against an abutment 13 provided on the lower
casing shell 5. The reference numeral 14 indicates a central
opening for introducing the bolt 2 of the other button half 1. When
inserting the bolt 2 into the central opening 14 the bolt 2 will at
first engage the retaining edges 15, 16 of the retaining disks 8, 9
so that these disks will recede against the force of the spring 12
and then engage the locking groove 3 thus retaining the bolt 2.
As shown in FIG. 3 the key consists in this first embodiment of a
resilient two-legged hooked clamp whereby each of the two legs of
the clamp is provided with a hook 17 at its end portion and adapted
to be inserted through openings 18 in the casing shell 4 of the one
button half as well as through recesses 19 in the two retaining
disks 8, 9 which recesses are aligned with the openings 18 of the
casings 4 and located behind these latter openings so that as a
result of the resiliency of the hooked clamp these hook portions
engage the retaining disks on their opposite sides and tilt the
disks 8, 9 against the force of the return spring 12 when
withdrawing the hooked clamp. As may be readily seen, withdrawing
the hooked clamp towards the one side and immediately thereafter or
simultaneously pulling out the button half with the bolt 2 out of
the opening 14 may be carried out more easily than disengaging the
button halves of the above-described known lock button.
As shown in FIG. 4, the key may also be provided in the form of a
magnetic plate 20 having a handle 21 instead of a key in the form
of a hooked clamp. When this magnetic plate 20 is brought into
registration with the plane surface 23 of the casing 4 of the one
button half a force of attraction is exerted onto the retaining
disks 8, 9 which are made of steel or any other suitable magnetic
material. By this attraction force the retaining disks are tilted
against the axially directed force of the return spring 12. The
application of such a type of key is extremely simple and requires
still less manual force for disengaging the lock button.
In FIGS. 5 and 6 are shown rigid solid bodies 21, 22 such as plates
or bars in which a button half is built in respectively. The bodies
21, 22 may be of wood, plastic or any other rigid material into
which other bodies may be embedded by screwing, a press fit or in
any other manner. The reference numeral 23 indicates a
sleeve-shaped body which is firmly embedded in one of the two rigid
bodies and within which is mounted for movement against the force
of a return spring 24 the one button half such as the button half 4
of FIG. 4 or the button half 1 of FIG. 9. This allows, for example,
to join together the rigid bodies 21, 22 shown in FIGS. 5 and 6 so
that the locking bolt 2 enters the opening 25 and the contact
surfaces of the parts 21, 22 come into contact with each other
without the retaining disks 8, 9 engaging the locking groove 3 on
the bolt 2. This engagement will not be effected until a pressure
is applied to the button half 4 by depressing this part with a
finger or the like from the upper surface of the part 21. By the
application of this pressure the button half 4 is depressed and the
retaining disks 8, 9 engage into the locking groove 3. This firmly
connects the rigid parts 21, 22. Disengagement of these two parts
is likewise effected by brining the key 20 into registration with
the upper surface of the button half 4. The key 20 then attracts
the retaining disks 8, 9 of a magnetic material so that these
retaining disks are tilted upwardly against the force of the return
spring 12 and thereby come out of engagement with the locking
groove 3 so that the casing-shaped button half 4 may be urged
upwardly by its return spring 24 and the rigid bodies 21, 22 may be
separated.
In the somewhat modified embodiments shown in FIGS. 8 and 9 the
casing-shaped button half 4 is firmly built into the rigid part 21
whereas the button half 1 carrying the bolt 2 is movably mounted at
the rigid part 22. Toward this purpose, the button half 1 is
mounted for movement against the return spring 24 within the sleeve
23 which is rigidly connected to the part 22 by a screw arrangement
or the like. Since in some cases it may be undesirable if the
locking bolt 2 freely protrudes from the one part when the parts
are separated a setscrew 26 may be provided for retaining the bolt.
As soon as this setscrew 26 is removed the button half 1 is urged
upwardly by the spring 24. The locking bolt 2 then projects from
the surface of the part 22 and may be inserted into the opening 25
of the button half 4 when the contact surfaces of the parts 21 and
22 are brought into engagement. The bolt 2 will then come into
engagement with the retaining disks 8, 9 which in the already
described manner snap into the locking groove 3. Disengagement may
be effected in the already described manner by means of the
magnetic key 20.
It will be understood that there may be provided further
embodiments in which each of the button halves is directly
incorporated into a rigid part 21 or 22 respectively.
FIG. 10 illustrates an application of the invention to a toy box,
for example. This box has the shape of a square block, and the
plane boundary surfaces of the block may be composed of detachable
wall portions bordering each other at the parting lines indicated
in the drawing. The small circles in this drawing indicate the
locations at which lock buttons according to the present invention
may be installed. The one button half of these lock buttons is
installed in the respective wall portion whereas the other
corresponding button half is installed in a supporting or
connecting element (not shown in this drawing) arranged on the
interior of the box.
The actual attachment arrangement is schematically shown in FIG.
11. The reference numerals 30, 31, 32 indicate wall portions of the
outer boundary walls of a hollow body such as the box of FIG. 10.
The reference numerals 33, 34 indicate supporting or connecting
elements such as bars arranged on the interior of the box. The
two-part lock buttons for effecting the described detachable
connection are schematically indicated by symbols 35 in the shape
of a "H" or a small circle respectively and are arranged with their
one half in a wall portion and with their corresponding other half
in a supporting or connecting element. The one half of each lock
button, i.e., the casing-shaped half containing the retaining disks
is accessible from the outside of the hollow body thus allowing to
apply the magnetic key 20 for disengaging the button halves.
In the embodiment of the lock button illustrated in FIGS. 12 and 13
the reference numeral 1 indicates a button half carrying a lock
bolt 2 having four locking grooves 3, 3a, 3b, 3c. The retaining
disks 8, 9 are supported at their outer bottom portions on an
annular padding 40 of foamed plastic material or the like. The
number of locking grooves 3, 3a, 3b, 3c may be freely chosen, as
well as the mutual spacings of the locking grooves which may be
equal or different.
In order to be able to insert the locking bolt 2 of the button half
1 up to a desired depth into the button half 4 the upper cover
plate 4a of the casing of the button half 4 is provided with a
center aperture 41 so that the locking bolt 2 which is longer than
the depth of the casing of the button half 4 may protrude by its
upper end beyond the button half if the bolt 2 has been fully
inserted into the button half 4 and the retaining disks 8, 9 engage
into the lowermost locking groove 3c of the locking bolt 2. The
disengagement of the two parts 4 and 1 is effected by bringing the
magnetic key 20 into registration with the surface of the button
half 4. Toward this purpose, the key 20 is likewise provided with
an aperture 42 thus allowing to bring the key 20 into registration
with the upper surface of the casing of the button half 4 if the
free end of the locking bolt 2 projects beyond this upper surface.
In this case, separation of the two parts 1, 4 is likewise effected
by applying the magnetic key 20.
In the embodiment shown in FIG. 14 three button halves 4 are
assembled on top of each other and are mounted for joint axial
movement in a guide sleeve 23 provided with a bottom plate 23a,
this movement being effected against the force of a spring 24 which
is in engagement with the bottom plate 23a. For introducing the
locking bolt 2 having several locking grooves 3, 3a, 3b, 3c of the
button half 1 the bottom plate 23a of the guide sleeve 23 is
provided with a center aperture 43. The uppermost button half 4 is
restricted in its movement by abutments 23b of the guide sleeve 23.
The casings of the three button halves 4 may also be arranged in
one piece. The spacings of the locking grooves 3, 3a, 3b, 3c of the
locking bolt 2 are arranged such that the retaining disks 8, 9 of
the button halves 4 may engage three locking grooves when inserting
the locking bolt 2 into these button halves 4. By the engagement of
the retaining disks 8, 9 of two or three or even several button
halves 4 arranged on top of each other a secure attachment of the
button halves unit on the button half 1 is assured.
The disengagement of the guide sleeve 23 with the three button
halves 4 from the button half 1 is likewise effected by bringing
the magnetic key 20 into registration with the upper button half 4.
In order to swivel all of the retaining disks 8, 9 of all button
halves 4 simultaneously out of the locking grooves of the locking
bolt 2 these retaining disks 8, 9 of all button halves 4 are
connected by means of guide rods 44, 45 which are guided in their
movements by bores 46, 47 in the upper and lower wall portions of
the casings of the several button halves 4. The points of
attachment of the guide rods 44, 45 with all of the retaining disks
8, 9 respectively are indicated at 48, 49. Bores which correspond
to the bores 46, 47 are likewise provided in the retaining disks 8,
9.
An example of an application of a two-part lock button according to
the invention may be the closure member of bandages or holding
devices for restless sick persons. The invention however readily
offers itself to many other applications and is not restricted to
the described and illustrated details. Thus it is possible, for
example, to provide a mechanical key for detaching the button
halves, instead of a magnetic key. Furthermore the range of
application is not restricted to collapsible hollow bodies but also
includes all kinds of objects capable of being dismounted. Various
objects of practical usage as well as toys, assemblies with
replaceable components and assemblies of separable components not
intended to be replaced may be fitted with button halves according
to the present invention. For unlocking the retaining disks also
the magnetic force provided by a remote controlled electromagnet
may be employed instead of a key in the form of a permanent
magnet.
* * * * *