U.S. patent number 3,871,832 [Application Number 05/448,360] was granted by the patent office on 1975-03-18 for test tube rack.
This patent grant is currently assigned to Institut de Bio-Endrocrinologie, Inc.. Invention is credited to Alcide Leblanc.
United States Patent |
3,871,832 |
Leblanc |
March 18, 1975 |
TEST TUBE RACK
Abstract
A test tube rack expressly constructed for expedient chemistry
analysis in industrial laboratories is provided with means to hold
a plurality of test tubes and to seal them after filling so that
the contents may be mixed adequately. The rack includes a bottom
shelf recessed to receive the lower ends of the test tubes and a
cover with a locking mechanism especially designed to provide a
quick connect and disconnect operation. The cover is lined with a
resilient sheet impervious to chemical compounds so as to provide a
hermetic seal to the test tubes, the resiliency allowing for height
differential between the ends of different size tubes.
Inventors: |
Leblanc; Alcide (Montreal,
Quebec, CA) |
Assignee: |
Institut de Bio-Endrocrinologie,
Inc. (Montreal, CA)
|
Family
ID: |
23779998 |
Appl.
No.: |
05/448,360 |
Filed: |
March 5, 1974 |
Current U.S.
Class: |
422/562;
422/569 |
Current CPC
Class: |
B01L
9/06 (20130101) |
Current International
Class: |
B01L
9/00 (20060101); B01L 9/06 (20060101); G01n
001/10 (); B01l 003/14 () |
Field of
Search: |
;23/259,253R,292 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Serwin; R. E.
Attorney, Agent or Firm: Cushman, Darby & Cushman
Claims
What I claim is:
1. A locking mechanism for locking a removable cover over a
plurality of open ended tubes of a test tube rack, the cover
including a resilient liner on the lower face thereof, comprising,
in combination: vertical securing means having one end mounted to a
bottom wall of said rack and having at the opposite end thereof a
portion protruding said cover; actuator means having an upper
portion disposed above said cover and a lower portion slidably
mounted through said cover; lever means pivotally attached to one
end thereof to the upper portion of said actuator means, the other
end thereof defining engagement means for engaging said protruding
portion of said securing means; pivot means on said lever means in
contacting engagement with the upper face of said cover, and being
slidable thereon whereby, upon downward movement of said actuator
means, said lever means are moved to said protruding portion of
said securing means and said engagement means tightly secure said
protruding portion to provide a sealing engagement between the
liner and the tubes, the resiliency in said liner allowing for
height differential between the ends of the tubes.
2. A locking mechanism as defined in claim 1, said actuator means
being centrally located on said cover and including a pair of said
lever means in securing engagement with a pair of said securing
means symmetrically disposed on each side of said actuator
means.
3. A locking mechanism as defined in claim 1, further comprising
means mounted on said bottom wall of said rack for adjusting the
relative position of said securing means with respect to said
cover.
4. A locking mechanism as defined in claim 3, further comprising
spring means disposed between said bottom wall of said rack and
said securing means for upwardly urging said securing means when
adjusted.
5. A locking mechanism as defined in claim 1, wherein said
protruding portion of said securing means above said cover includes
a mouth-shaped opening sufficiently large to receive said
engagement means and said pivot means therein.
6. A locking mechanism as defined in claim 5, wherein said pivot
means include a pin extending transversely of said lever means and
a roller mounted on said pin.
7. A locking mechanism as defined in claim 5, wherein said actuator
means include at least one slot to receive therein the end of said
lever means which is pivotally attached thereto, said slot
providing easy access of the other end of said lever means to said
mouth-shaped opening of said protruding portion of said securing
means.
8. A locking mechanism as defined in claim 1, wherein the pivot
axis of said pivot means and the pivot axis of said end of said
lever means pivotally attached to said actuator means are in
substantially horizontal plane when said lever means are in a
locking engagement with said protruding portion; said engagement of
said lever means including a pin extending transversely and
horizontally in said lever means, the pivot axis of said pin being
slightly offset with respect to a vertical plane passing through
said pivot axis of said pivot means, the offset being an
inclination toward said actuator means.
9. A test tube rack comprising, in combination: a bottom shelf
having a series of depressions adapted to receive therein the lower
end of test tubes; a horizontal tube support extending above from
said bottom shelf and having a series of openings to receive
therethrough the test tubes; vertical support means attached to
said bottom shelf for supporting said horizontal support; a
removable cover adapted to be in covering arrangement over the open
ends of the test tubes; a resilient liner fixed to the lower face
of said cover and adapted to contact the open ends of the test
tubes; vertical securing means having one end fixed to said bottom
shelf and having at the opposite thereof a portion protruding said
cover; cover actuator means having an upper portion disposed above
said cover and a lower portion slidably mounted through said cover;
lever means pivotally attached at one end thereof to the upper
portion of said actuator means, the other end thereof defining
engagement means for engaging said protruding portion of said
securing means; pivot means on said lever means in contacting
engagement with the upper face of said cover and being slidable
thereon whereby, upon downward movement of said actuator means,
said lever means are moved to said protruding portion of said
securing means and said engagement means tightly secure said
protruding portion to provide a sealing engagement between the
liner and the tubes, the resiliency in said liner allowing for
height differential between the ends of the tubes.
10. A test tube rack as defined in claim 9, further comprising
resilient means in said depressions in said bottom shelf to provide
resiliency at the opposite end of the tubes when engaged between
the liner and the bottom shelf.
11. A test tube rack as defined in claim 9, wherein said
depressions include orifices therein for discharging waste contents
collected in said depressions.
12. A test tube rack as defined in claim 9, wherein means are
provided on the bottom shelf for adjusting the vertical height of
said securing means relative to said cover; means being provided
beneath said bottom shelf for indicating the adjustment made on
said securing means.
Description
FIELD OF THE INVENTION
The present invention relates to a rack for retaining multiple
spaced test tubes. More particularly, the invention pertains to an
improved locking device for placing the cover of the rack in
sealing position over the open ends of the test tubes and for
providing quick connect and disconnect operation.
BACKGROUND OF THE INVENTION
In industrial laboratories, test tubes may be used, for example, to
receive different samples of blood. These tubes are closed with
glass or rubber stoppers to allow a mixing of the contents therein.
Obviously, the opening and closing procedures involved with these
tubes are laborious and time-consuming and most stoppers carry
plenty of practical difficulties. The price of these tubes is
especially high if all the components of a tube are made of glass.
In the cases where cork or rubber caps are used, the price may be
reduced but there are plenty of leaks and often rubber is attacked
by some of the chemical solvents. There is also a danger of
contamination with any kind of stoppering because of a possible
mix-up with the respective stoppers of a series of tubes.
Another disadvantage of present known methods is a lack of
uniformity of results. Since all mixing operations are individually
carried out and it is practically impossible to have a series of
identical operations.
STATEMENT OF THE INVENTION
It is an object of the present invention to provide a test tube
rack which is constructed for expedient chemistry analysis in
industrial laboratories and which overcomes the above mentioned
disadvantages by saving valuable time and labor and ensuring
non-contamination of the contents in the test tubes.
The test tube rack made in accordance with the present invention
consists of a bottom shelf and a spaced parallel support arranged
to receive a series of test tubes disposed in longitudinal and
lateral rows. A removable cover is provided for simultaneously cap
the test tubes. The lower face of the cover includes a liner made
of a resilient resistant sheet impervious to chemical compounds so
as to provide a hermetic seal for the test tubes. The rack also
includes an improved locking mechanism which enables a quick
connect and disconnect operation for capping and decapping the test
tubes.
With a rack made in accordance with the present invention, the
height of the tubes positioned therein is no longer critical since
any difference in their height is taken up by the resiliency in the
liner. For additional resiliency, small rubber cushions may be
placed in concave depressions provided in the bottom shelf and
serving as seats for the lower part of the test tubes.
Also, all mixing and agitating operations are now carried out
simultaneously; this confers homogeneity of results. It is well
known that all batches include blanks and any known or unknown
values are the same for the testing of all tubes of one rack.
The novel locking mechanism of the present invention consists of
securing means which are mounted to the bottom shelf of the rack
and have a portion protruding the cover; actuator means are
disposed above the cover have a lower portion slidably extending
through the cover; lever means are pivotally attached at one end
thereof to the upper portion of the actuator means. The other end
of the lever means is provided with engagement means for engaging
the protruding portion of the securing means. Pivot means are
provided on the lever means and are in contact engagement with the
upper face of the cover. On downward movement of the actuator
means, the lever means move outwardly to the protruding portion of
the securing means where the engagement means engage the said
protruding portion to provide a tight sealing engagement between
the liner and the tubes.
BRIEF DESCRIPTION OF THE DRAWINGS
Other objects, purposes and characteristic features of the present
invention will be in part obvious from the accompanying drawings
and in part pointed out as the description of the invention
progresses. In describing the invention in detail, reference will
be made to the accompanying drawings, in which like reference
characters designate corresponding parts throughout the several
views, and in which:
FIG. 1 is an elevational view of a test tube rack made in
accordance with the present invention;
FIG. 2 is a cross-sectional view taken along lines 2--2 of FIG. 1;
and
FIG. 3 is an elevational view showing part of the rack of the
present invention and illustrating the locking mechanism in the
opened position.
DESCRIPTION OF PREFERRED EMBODIMENT
Referring to FIG. 1, there is illustrated a rack 10 having a bottom
shelf 12 of rectangular flat shape and having extending vertically
at each corner thereof a series of vertical supports 14 (two of
which are shown). Spaced parallel and above the bottom shelf 12 is
an intermediate support 16 which is fixedly attached at its corners
to the supports 14 by appropriate securing means, such as pairs of
nuts 18 and 19 threadedly mounted on the supports 14.
The bottom shelf 12 is provided with a series of circular concave
depressions 20 which are adapted to receive the lower part of a
series of open end test tubes 22 arranged in longitudinal and
lateral rows. The intermediate support 16 is provided with a series
of openings 26 which are in vertical registry with the lower
depressions of the bottom shelf 12; support 16 ensures the vertical
support of the test tubes 22 in the rack.
A cover 28 of rectangular shape is adapted to be laid over the open
ends of the test tubes 22. The cover includes a top plate 29 and a
liner 30 secured to the lower face of the plate 29; the liner is
made of a resilient resistant sheet of material impervious to
chemical compounds and its function will be described
hereinbelow.
An important characteristic of the present invention is a novel
locking mechanism for locking the cover 28 in a sealing engagement
over the open ends of the test tubes. This locking mechanism
consists of a pair of securing means in the form of a vertical
plate member 32 which has its lower end fixed to the bottom shelf
12 and which has, as its opposite upper end, a portion 34 that
protrudes the top plate 29 and the liner 30. Plate 32 may be
adjusted vertically relative to the bottom shelf by means of a
screw 46 threadedly engaged thereto, the head 48 of the screw being
accessible beneath the bottom shelf. When the plate is adjusted to
raise it relative to shelf 16, a spring 50 disposed between the
plate and the shelf upwardly urges the plate. The novel locking
mechanism further includes an actuator means 36 slidably mounted to
the cover 28 and a pair of lever means 38, each having one end 40
pivotally mounted to an upper part of actuator means 36 and the
other end 42 equipped with engagement means 44 for engaging the
protruding portion 34 of the securing plate 32.
The actuator means 36 consists of a flat handle 52 and of an
elongated plate 54 extending through the plate 29 and the liner 30.
A pin 56 extends transversely of the plate 54 at its lower edge to
engage liner 30 and to subsequently lift the cover plate 28 when
the actuator means are pulled upward. Two curved slots 58 on the
upper part of plate 54 receive the cross pins 60 which extend
transversely through the fork-shaped upper ends 40 of the levers
38.
The opposite end 42 of the lever means is also fork-shaped and
receives transversely thereof a pin 44. A similar transverse pin 62
extends lower on the lever means and supports a roller 64 which is
adapted to slide on the upper face of the top plate 29 of the
cover.
The protruding portion 34 of the securing plate 32 has a
mouth-shaped opening sufficiently large to receive the engagement
means 44 and the roller 64 of end 42 of the lever means.
Appropriate slots are provided in the intermediate support 16,
plate 29 and liner 30 to allow the passage of plates 32 and 54
therethrough; as seen in FIG. 2, slots 66 are provided to allow
passage of plates 32 while slot 68 allows passage of the actuator
plate 54. Similar slots are found on cover 28. Slot 68 further
includes two opposite recesses 70 and 72 to allow passage of the
cross-pin 56 of plate 54; however, similar recesses are not found
on cover 28 since this pin 56 serves to engage the cover as the
latter is raised.
OPERATION OF THE EMBODIMENT
Referring first to FIG. 3, the locking mechanism is shown in a free
position, that is when the cover is raised or as the actuator means
begins its downward actuation. In this position, the liner 30 lays
over the open ends of the test tubes. As the actuator begins its
downward travel, ends 42 of the lever means move outwardly toward
the mouth-shaped openings 44 of the upper portions 34 of the
securing means 32. Pins 60 are at their lowest point in their
respective slots 68; the slots allow easy passage of the lever
means 38 between the actuator plate 54 and the protruding portion
34 of the securing means. In a horizontal position, the levers
would not clear the uppermost and inmost extremity of portions 34.
As the engagement means 44 contact the inside edge of opening 45,
pins 60 roll up the slots 58 at their uppermost point. There, the
actuator is held suspended.
To lock the cover plate in sealing engagement with the upper ends
of the test tubes, actuator 52 is further pushed downward in
forcing manner since pins 44 are already in contact with portion
34. There results a pivot movement of the lever 38 about pin 62
which continues to further move outwardly and enter in opening 45.
There, the locking mechanism is as that shown in FIG. 1 where the
ends 42 are entirely received in the mouth-shaped opening 45 and
where the pins 60 and 62 are substantially in a horizontal plane.
Although not illustrated in the drawings, the plane that includes
pins 62 and 44 is slightly offset toward the actuator means with
respect to a vertical plane that includes pin 62. With this
arrangement, a force must be exerted on the actuator 52 to allow
pin 44 to rotate back in this vertical plane before being retracted
from the mouth-shaped opening 45.
With this arrangement, a satisfactory sealing engagement is
obtained between the liner 30 and the upper ends of the test tubes.
When forcing the cover plate on the test tubes, the resiliency in
liner 30 takes up any height differential in the various test tubes
of the rack. To enhance this resiliency action, rubber rings (not
shown) may be positioned in the circular depressions 20 of the
bottom shelf 12.
Although the invention has been described with respect to one
specific form, it is evident that it may be modified and refined in
various ways. For example, an indicator could be provided to the
under surface of the bottom shelf 12 to indicate the degree of
variation given to the screw 46. It is therefore wished to have it
understood that the present invention is not limited in
interpretation except by the terms of the following claims.
* * * * *