U.S. patent number 3,831,742 [Application Number 05/298,077] was granted by the patent office on 1974-08-27 for dental mixing capsule.
This patent grant is currently assigned to Pennwalt Corporation. Invention is credited to Anthony Ciavattoni, John M. Gardella, Robert Albert Kiefer.
United States Patent |
3,831,742 |
Gardella , et al. |
August 27, 1974 |
**Please see images for:
( Certificate of Correction ) ** |
DENTAL MIXING CAPSULE
Abstract
A capsule has a hollow body defining a first compartment having
an open end which is closed by a retainer, the latter being
telescopically mounted within the hollow body. The retainer defines
a second compartment having an open end, the second compartment
being isolated from the first compartment by a frangible partition,
the latter being an integrally molded portion of the retainer. The
first and second compartments are utilized for storing first and
second ingredients respectively. To seal the second material within
the second chamber, a cap having a plunger is telescopically
mounted over the capsule body, with the end of the plunger
extending into the open end of the second chamber in a sealing
relationship therewith. To use the capsule to mix the ingredients,
it is compressed endwise so as to force the plunger inwardly to
increase the pressure on the second ingredient (preferably liquid),
rupture the partition, and eject the second ingredient into the
first chamber. The capsule is then shaken to mix the ingredients,
and the cap and retainer are pulled from the body as a unit to
provide access to the mixture. The capsule may be compressed by
hand alone or with the assistance of a special tool.
Inventors: |
Gardella; John M. (Matawan,
NJ), Ciavattoni; Anthony (New Drop, NY), Kiefer; Robert
Albert (Toms River, NJ) |
Assignee: |
Pennwalt Corporation
(Philadelphia, PA)
|
Family
ID: |
23148919 |
Appl.
No.: |
05/298,077 |
Filed: |
October 16, 1972 |
Current U.S.
Class: |
206/219 |
Current CPC
Class: |
A61C
5/66 (20170201) |
Current International
Class: |
A61C
5/06 (20060101); A61C 5/00 (20060101); B65d
081/32 () |
Field of
Search: |
;206/47A |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
|
|
|
|
|
|
|
1,180,181 |
|
Feb 1970 |
|
GB |
|
1,445,946 |
|
Jun 1966 |
|
FR |
|
Primary Examiner: Dixson, Jr.; William T.
Attorney, Agent or Firm: Sager; Edward A.
Claims
What is claimed is:
1. A mixing capsule for storing at least two ingredients separately
until said ingredients are subsequently brought together and mixed
within said capsule, said capsule comprising:
a. a body defining a first chamber having an opening at one end
thereof and being adapted to store a predetermined amount of a
first of said ingredients,
b. a retainer telescopically mounted to said body and closing said
opening at said one end of said first chamber, said retainer having
means including a peripheral wall and a frangible partition molded
integrally with said peripheral wall for defining a second chamber,
said second chamber having a first opening at one end thereof and
being adapted to store a predetermined amount of a second of said
ingredients, said partition being disposed at said other end of
said second chamber and having at least one pre-scored line formed
therein defining a weakened zone which is adapted to be ruptured so
as to define a second opening at said other end of said second
chamber, said pre-scored line being formed on the side of said
partition which is adjacent said first chamber, said retainer being
disposed on said body so that said partition isolates said first
chamber from said second chamber prior to said partition being
ruptured,
c. a cap having a plunger, said plunger having an end adapted to be
inserted into said opening in said one end of said second chamber,
said plunger having a protrusion extending around the periphery
thereof adjacent said end thereof, said protrusion being
dimensioned so as to have an interference fit with said peripheral
wall, said plunger extending into said second chamber, so that said
protrusion is in contact with said peripheral wall adjacent said
first opening of said second chamber to seal said second ingredient
therein, the cross-sectional area of said first and second chambers
each being larger than the cross-sectional area of said partition,
the fit between said body and said retainer, and between said
retainer and said protrusion being such that said ingredients are
sealed within said chambers, but which will permit said cap and
said retainer to be pulled as a unit from said body,
d. said capsule having means for stopping the telescopic movement
of said retainer with respect to said body when initially
assembling said capsule so as to locate said retainer at a
predetermined position and prevent further movement of said
retainer when said plunger is pushed into said second chamber,
e. said retainer being disposed at least partly within said body,
said cap including a skirt surrounding said body, said skirt having
a protusion extending around the inner peripheral surface thereof,
said protrusion being in sliding contact with the outer peripheral
surface of said body,
f. whereby when it is desired to use said capsule to mix said first
and second ingredients, said capsule is compressed endwise so as to
move said plunger from its initial position inwardly into said
second chamber to pressurize said second ingredient, rupture said
partition, and eject said second ingredient into said first chamber
where it is brought together with said first ingredient, and after
mixing said ingredients within said capsule, said cap and said
retainer are pulled as a unit from said body to allow the mixture
to be easily removed from said first chamber.
2. A mixing capsule as set forth in claim 1, wherein said retainer
includes means defining a shoulder surrounding said partition and
facing said first opening of said second chamber, said shoulder
being adapted to stop the inward movement of said plunger into said
second chamber, said end of said plunger being inclined from
adjacent the periphery thereof from completely closing, thus
assuring that all of said second ingredient is ejected from said
second chamber.
3. A mixing capsule as set forth in claim 2, wherein said first and
second chambers each has a circular cross-section, said capsule
including means defining a concave surface closing said other end
of said first chamber, and said retainer including a surface
defining a retainer opening extending from said partition toward
said other end of said first chamber, at least a portion of said
retainer opening having an increasing circular cross-sectional area
as it extends toward said other end of said first chamber.
4. A mixing capsule as set forth in claim 1, wherein the other end
of said first chamber has an opening therein, said capsule further
including:
a. a second retainer telescopically mounted to said body and
closing said opening in said other end of said first chamber, said
second retainer having means including a peripheral wall and a
frangible partition molded integrally with said latter peripheral
wall for defining a third chamber, said third chamber having a
first opening at one end thereof and being adapted to store a
predetermined amount of a third of said ingredients, said latter
partition being disposed at said other end of said third chamber
and being adapted to be ruptured so as to define a second opening
at said other end of said third chamber, said second retainer being
disposed on said body so that said latter partition isolates said
first chamber from said third chamber prior to said latter
partition being ruptured,
b. a second cap having a plunger, said latter plunger having an end
adapted to be inserted into said opening in said one end of said
third chamber, said latter plunger having a protrusion extending
around the periphery thereof adjacent said end thereof, said
protrusion being dimensioned so as to have an interference fit with
said latter peripheral wall, said latter plunger extending into
said third chamber so that said protrusion is in contact with said
latter peripheral wall adjacent said first opening of said third
chamber to seal said third ingredient therein, the cross-sectional
area of said first and third chambers each being larger than the
cross-sectional area of said partition,
c. said capsule having means for stopping the telescopic movement
of said second retainer with respect to said body when initially
assembling said capsule so as to locate said second retainer at a
predetermined position and prevent further movement of said second
retainer when said latter plunger is pushed into said third
chamber.
5. A mixing capsule as set forth in claim 4, wherein said third
chamber has a circular cross-section, and wherein said second
retainer includes a surface defining a retainer opening extending
from said latter partition toward said one end of said first
chamber, at least a portion of said latter retainer opening having
an increasing circular cross-sectional area as it extends toward
said one end of said first chamber.
6. A mixing capsule as set forth in claim 5, wherein said second
retainer is disposed within said body, and wherein said second cap
includes a skirt surrounding said body, said latter skirt having a
protrusion extending around the inner peripheral surface thereof,
said latter protrusion being in sliding contact with the outer
peripheral surface of said body.
7. A mixing capsule as set forth in claim 1, wherein said second
opening at said other of said second chamber is sufficiently
restricted so that said second ingredient is ejected in the form of
a forceful jet stream which will reach said other end of said first
chamber.
Description
BACKGROUND OF THE INVENTION
This invention relates in general to a mixing capsule, but one
particularly to a dental mixing capsule in which two or more
ingredients are stored separately; the ingredients are subsequently
brought together and mixed in the capsule.
In a conventional dental mixing cpasule, two or more ingredients of
a filling material are stored in individual sealed compartments or
chambers within the capsule. Examples of such a capsule are shown
in each of the following patents: U.S. Pat. No. 3,451,540; U.S.
Pat. No. 1,774,258; U.S. Pat. No. 3,595,439; U.K. Pat. No.
1,107,894; Austrian Pat. No. 188,032; German Auslegeschrift No.
2,009,403; and German Offenlegungschrift No. 1,955,996. Within such
a capsule, there is usually a measured dose of one liquid
ingredient and a measured dose of one solid ingredient, the latter
preferably being in dry powdered form. In order to prepare the
filling material, a partition separating the individual
compartments is generally ruptured by endwise compression of the
capsule so that the ingredients are brought together, and the
ingredients are mixed by vigorously shaking the capsule; the
mixture is then removed from the capsule for use.
Numerous problems are encountered in using the conventional
capsules of the prior art. In many instances, a cap having a
plunger is telescopically mounted to an open end of a hollow
capsule body, and when it is desired to bring the ingredients
together, the capsule is compressed endwise, thus pushing the
plunger inwardly into the capsule body to rupture one or more
frangible partitions. Because of a loose fit between the plunger
and the inner peripheral wall of the capsule body, "splashback"
(i.e., leakage of the liquid ingredient around the plunger) often
occurs as the plunger moves inwardly. If an attempt is made to
eliminate the "splashback" problem by dimensioning the diameter of
the plunger so that there is a tighter fit between it and the
peripheral wall of the capsule, a second problem is created; this
latter problem is the considerable additional force now required to
move the plunger inwardly because of the increased frictional
resistance between the plunger and capsule body.
Other factors also contribute to requiring considerable force to
move the plunger inwardly in conventional capsules. One of these
factors is that in many instances, the plunger itself must directly
rupture a first partition which covers the end of the capsule body.
In such an instance, not only is considerable force required to
move the plunger inwardly to rupture the end partition, but it is
also very difficult to guide the plunger as it is moving. Some
plungers have pointed cutters or projections which cut the
partitions as the plungers are moved inwardly into the capsule
body. In some instances, severed pieces of the partition then fall
into and becomes mixed with the ingredients. In other instances the
ruptured partition remains affixed to the capsule body, but becomes
lodged between the plunger and the peripheral wall of the body; in
at least one such capsule, this leaves a space between the plunger
and the capsule body wherein portions of the ingredients become
trapped.
Where the partition is a separate element which must be affixed to
the capsule by an adhesive or other means, it is difficult to
effect an air-tight seal between them; with such an arrangement,
the partition as a whole may become detached, fall into, and become
mixed with the ingredients when the plunger is moved inwardly.
Also, in some conventional capsules, it is very difficult to remove
the ingredients after they are mixed because of the peculiar
construction of the capsules.
Consequently, what is needed, is a single capsule which overcomes
these and other problems of the capsules of the prior art.
SUMMARY OF THE INVENTION
The present invention relates to a dental capsule having a hollow
body which defines a first chamber having an open end, the first
chamber being used to store a first ingredient. Closing and sealing
the open end of the first chamber is a retainer which is
telescopically mounted within the capsule body. The retainer
defines a second chamber having an open end, the second chamber
being isolated from the first chamber by a frangible partition
which is an integrally molded portion of the retainer; the second
chamber is used to store a second ingredient (preferably liqud). To
seal the second ingredient within the second chamber, a cap having
a plunger is telescopically mounted to the capsule body, one end of
the plunger extending into the open end of the second chamber. A
protrusion extends around the periphery of the plunger adjacent the
one end thereof, the protrusion being dimensioned so as to have an
interference fit with the peripheral wall of the second chamber;
this assures that an air-tight seal is formed between the plunger
and the retainer.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of the preferred embodiment of the
assembled capsule ready for use.
FIG. 2a is a longitudinal sectional view taken along line 2a--2a of
FIG. 1.
FIGS. 2b, 2c, and 2d are longitudinal sectional views similar to
FIG. 2a, but showing the component parts of the capsule in various
positions during the use of the capsule.
FIG. 3 is a sectional view taken along line 3--3 of FIG. 2a and
showing prescored lines on the partition.
FIG. 4 is a sectional view taken along line 4--4 of FIG. 3.
FIG. 5 is a longitudinal sectional view of a modified capsule which
is used for storing three ingredients separately.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring to FIGS. 1 and 2, the capsule 10 is comprised of three
main component parts, a cap 12 and a capsule body 14, each of which
has a plurality of longitudinally extending ridges 16 formed
thereon, and a retainer 18. The ridges 16 aid in grasping and
manipulating the capsule during use. Although other materials may
be used, high density polyethylene is a suitable material to use in
molding the cap 12 and the body 14, and low density polyethylene is
a suitable material to use in molding the retainer 18.
As can be seen, the body 14 defines a chamber 20, the latter having
a circular cross-section and being symmetrically disposed about an
axis 22. Chamber 20 is utilized to store a predetermined amount of
a first ingredient 24 (e.g., a powdered silver alloy or other
flowable substance). The opening 26 at one end of the chamber 20 is
closed by the retainer 18 which is telescopically mounted within
the body 14. The body 14 defines a concave surface 28 for closing
the other end of the chamber 20.
The retainer 18 defines a second chamber 30 which is also
symmetrically disposed about axis 22 when the retainer is
telescopically mounted within body 14, the bottom of chamber 30
being defined by an annular shoulder 32 which surrounds a frangible
partition 34; the partition 34 is an intergrally molded portion of
the retainer 18. Chamber 30 is utilized to store a predetermined
amount of a second ingredient 36 (e.g., mercury or other flowable
substance) which is to be subsequently mixed with ingredient 24. To
stop the retainer 18 at a predetermined location when initially
mounting it within the body 14, an annular flange 38 is provided;
the latter also prevents the retainer from being pushed further
into the body 14 when the cap 12 is pushed into the retainer 18. It
is noted that a pair of prescored lines or depressions 40 and 42
(FIGS. 3 and 4) are formed in partition 34 to define a weakened
zone along which the parititon may be more easily ruptured when it
is desired to use the capsule to mix ingredients; these lines
intersect in the center of the partition 34. An opening which is
defined by concave surface 41 extends from the partition 34 toward
the other end (i.e., toward surface 28) of the body 14. As will be
apparent from the description which follows, surface 28 and 41
promote movement of the ingredients throughout chamber 20 during
the mixing operation.
To seal the ingredient 36 within the chamber 30, the cap 12 is
telescopically mounted to the body 14 so that one end of plunger 44
enters the opening 46 at one end of the chamber 30. An annular
protrusion 48 extends around the periphery of the plunger 44
adjacent the one end thereof, the protrusion being dimensioned so
as to have an interference fit with the annular wall defining
chamber 30. In its initial position (that shown in FIG. 2a), the
end of plunger 44 extends into the retainer 18 so that the
protrusion 48 is in contact with the annular wall defining chamber
30. As the plunger 44 is pushed inwardly into the retainer 18, the
material from which the retainer is made of "flows" around the
protrusion 48. With this arrangement, an air-tight seal is formed
between the retainer 18 and the plunger 44. As stated above, the
annular flange 38 prevents the retainer 18 from being pushed
further into the body 14 when the plunger 44 is pushed into the
retainer 18.
The cap 12 also includes an annular skirt 50, the latter
surrounding the body 14. Extending around the inner annular
peripheral surface of the skirt 50, is an annular protrusion 52,
the latter being in sliding contact with the outer peripheral
surface of the body 14. The protrusion 52 serves to guide the cap
12 as the plunger 44 is pushed inwardly into the retainer 18. As
shown in FIG. 2a, the end of plunger 44 has an incline or bevel 53
formed thereon, the incline extending from adjacent the periphery
of the plunger toward the center thereof, and toward the partition
34.
When it is desired to use the capsule 10 to mix the ingredients 24
and 36, the capsule is compressed endwise so as to push the plunger
44 inwardly from is initial position into chamber 30 against
ingredient 36. Because the latter is a liquid (i.e., mercury) in
the present example, this increases the hydrostatic pressure
sufficiently to rupture partition 34 along the lines 40 and 42, the
four ruptured segments of the partition forming an opening 54
through which the mercury is ejected into chamber 20 (FIG. 2b). As
stated above, the protrusion 48 prevents mercury from excaping
around the plunger 44 ("splashback") as the plunger is pushed
inwardly into chamber 30. It is apparent that with the present
embodiment, there are no severed pieces of the partition to fall
into the chamber 20. As compared to some of the conventional
capsules of the prior art which were discussed above, considerably
less force is required to push the plunger 44 inwardly into the
retainer 18, because the frictional resistance between the
protrusion 48 and the annular wall defining chamber 30 is
relatively small as compared to a conventional plunger which has a
uniform diameter along its entire length, but which diameter is
likewise dimensioned so as to have an interference fit with the
retainer; also, as compared to the latter instance, the protrusion
48 forms a superior seal between it and the retainer 18, because
the material from which the retainer is molded "flows" around the
protrusion as the plunger 44 is pushed inwardly into the
retainer.
The plunger 44 is pushed inwardly until the end thereof abuts the
annular shoulder 34 (FIG. 2c). At this point, the incline 53
prevents the ruptured partition 34 from closing completely and
assures that all of the mercury has been ejected from chamber
30.
After all the mercury from chamber 30 has entered chamber 20, the
capsule 10 may then be placed in an amalgamator for the mixing
operation. A suitable amalgamator for this purpose is the CAPMASTER
amalgamator sold by the S.S. White Division of Pennwalt
Corporation. Concave surfaces 28 and 41 serve to assure that the
ingredients are thoroughly mixed by promoting movement of the
ingredients throughout chamber 20 as indicated by the arrows 56. To
assure that the retainer 18 is pulled from the body 14 along with
the cap 12, the fit between the protrusion 48 and the retainer 18,
and the fit between the latter and the body 14 are closely
controlled. Except for the fange 38, the outer diameter of the
retainer 18 is uniform along its length. The inner diameter of the
body 14 (that defining chamber 20), however, varies along its
length, the inner diameter being the largest at the open end of
chamber 20. The outer diameter of retainer 18 and the inner
diameter of body 14 are dimensioned so that when the retainer is
mounted in its initial position (that shown in FIG. 2a), there is
an interference fit between the body 14 and the inner end of the
retainer 18 which will prevent leakage from chamber 20, but will
allow the retainer 18 to be pulled from the body 14 as a unit with
the cap 12 (FIG. 2d) when the mixing is completed.
Referring to FIG. 5, a modification is illustrated which is
utilized for storing 3 ingredients. The body 14' has been modified
so that each end of chamber 20' now has an opening 26'.
Each opening 26' is closed by the identical cap and retainer
arrangement illustrated in FIGS. 1 through 4, the lower retainer
(as viewed in FIG. 5) now serving to store the extra third
ingredient 36' (preferably a liquid) in its chamber 30.
* * * * *