Securing and locking assembly for live cell chambers

A securing and locking assembly for live cell chambers includes a ring shaped unit received in a circular shaped chamber base to be secured with an upper circular shaped chamber frame unit. The ring unit is rotatable over a limited arcuate distance, and includes four L-shaped fingers space 90.degree. apart and arranged to be received outside four 90.degree. spaced radially extending peripheral recesses formed in the upper chamber unit. Upon rotation of the ring unit a predetermined arcuate distance the fingers are positioned outside the recesses of the upper chamber frame unit and upon continuing rotation of yet another predetermined arcuate distance the upper portions of the fingers engage upper portions of the chamber frame unit to uniformly secure and lock the chamber base and upper chamber unit together. Rotating the ring unit in the opposite direction will result in the unlocking of the chamber base and the upper chamber unit from each other.

BACKGROUND OF THE INVENTION 
This invention relates to a securing and locking assembly for live cell 
chambers for use with light microscopes. 
Live cell chambers, typical of which is mine described in my U.S. Pat. No. 
4,974,952, issued to me on Dec. 4, 1990, include an upper chamber frame 
unit and a lower chamber base operatively engaging the upper chamber frame 
unit. A chamber or enclosure is defined when the chamber frame unit and 
chamber base are secured. As more fully described and illustrated in my 
said Patent, included within the enclosure are an upper seal unit, a 
fragile cover slip, an infusion/perfusion unit, and a lower gasket or 
gaskets. An infusion/perfusion chamber is formed between the cover slip 
unit, the lower gasket, and the infusion/perfusion unit. With the elements 
of the live cell chamber secured in place it is ready for use, as 
described, with an appropriate light microscope. 
A heretofore manner of securing chamber frame units to mating chamber bases 
was by use of machine screws received in threaded openings. The chamber 
frame units would thereby be secured and locked in place with the chamber 
bases. The machine screw arrangement of locking the elements in place 
demonstrated certain problems. Overtightening the screws resulted in 
breakage of infusion/perfusion units or other microscope slides used in 
the assemblies. Also, overtightening or uneven tightening the machine 
screws resulted in strain in the glass elements because of a resulting 
uneven arrangement of cover slips and slide units. It was also found that 
leakage ziones resulted between chamber frame units and chamber bases due 
to uneven tightening of the machine screws. Uneven arrangements of chamber 
frames and chamber bases also created uneven stress on the internal glass 
elements causing undesirable optical effects. When the surfaces of the 
internal glass elements of the live cell chamber were not parallel 
resulting from the uneven tightening of the external parts, undesirable 
optical cavities were formed between those glass elements. 
The problems resulting in improper securing and joining of the chamber 
frame units and chamber bases generally resulted in ineffective live cell 
chambers given to providing faulty results in their uses. To prevent the 
aforesaid problems careful machine screw tightening procedures were 
encouraged. The tightening procedures did not, however, insure eliminating 
of the problems, mainly because the possibility of human error in 
following the procedures were not eliminated. 
The securing and locking assembly of my present invention overcomes the 
heretofore problems associated with hand tightening of machine screws to 
secure and lock together chamber frame units and chamber bases, by 
providing uniform and positive securing and locking without the 
possibility of over-tightening or non-uniform tightening. By so providing, 
my invention prevents and eliminates leakage between the engaged 
interfaces of the chamber frame units and chamber bases, slide breakage, 
strain in the glass elements, and optical cavities due to uneven 
arrangement therebetween. The new results and advantages of the securing 
and locking assembly of my present invention are achieved with a simple 
combination of elements operable without the need of any tools or other 
aids. 
SUMMARY OF THE INVENTION 
This invention is a securing and locking assembly for live cell chambers. 
Typically, the live cell chambers include a chamber frame unit; a chamber 
base operatively engaging the chamber frame unit and forming an enclosure 
therewith; and cover slip windows and sealing units operatively associated 
with each other to form a live cell chamber. One such live cell chamber 
includes within the enclosure an upper seal unit operatively engaging the 
chamber frame unit, a cover slip unit operatively associated with the 
chamber base, an infusion/perfusion unit operatively associated with the 
cover slip, and lower gasket means operatively disposed intermediate the 
cover slip and the infusion/perfusion unit. The securing and locking 
assembly of this invention preferably comprises: rotatable securing means 
operatively engaging the chamber frame unit and the chamber base for 
uniformly securing and locking the chamber frame unit and the chamber base 
together upon rotation thereof through a predetermined arcuate distance 
and for unlocking the chamber frame unit and the chamber base upon reverse 
rotation the same arcuate distance. The securing means may be a rotatable 
ring unit received and supported by the chamber base, with the ring unit 
including uniformly spaced upwardly extending L-shaped fingers. A circular 
chamber frame unit may be provided with uniformly spaced radially 
extending peripheral recesses or notches shaped and sized such that the 
L-shaped fingers are positioned radially outside of the recesses. The ring 
unit is rotatable by hand and when rotating it the sides of the fingers 
will engage radial portions of openings through the chamber base. At that 
position the fingers will be arranged arcuately from the recesses with the 
upper legs of the fingers over the upper surface portions of the chamber 
frame unit. Continuing rotation of the ring unit results in uniform, 
simultaneous locking engagement by the fingers of upper portions of the 
chamber frame arcuately adjacent the recesses. Reverse rotation of the 
ring engagement will result in simultaneous disengagement of the fingers 
from the upper surface of the chamber frame unit and positioning of the 
fingers outside of the recesses to allow separation of the chamber frame 
unit and chamber base. The positive and uniform clamping and locking 
performance of the securing and locking assembly of the present invention 
eliminates the aforesaid problems inherent in the heretofore methods of 
joining and securing chamber frame units to chamber bases. 
Various other advantages, details, and modifications of the present 
invention will become apparent as the following description of a certain 
present preferred embodiment proceeds.

DESCRIPTION OF A PREFERRED EMBODIMENT 
Referring now to the drawings there is shown a typical live cell chamber 10 
embodying the securing and locking assembly of the present invention. The 
live cell chamber 10 is substantially the same in its primary elements and 
function as the live cell chamber described and claim in my U.S. Pat. No. 
4,974,952 issued on Dec. 4, 1990. It is to be understood, however, that 
the present invention is not limited to application with the live cell 
chamber of the Patent but, rather, is applicable to any live cell chamber. 
The basic and primary elements of the live cell chamber 10 shown in the 
drawings will be briefly described with the understanding that the more 
specific details of the elements and their respective functions may be 
found in U.S. Pat. No. 4,974,952. 
As shown throughout the various drawings, live cell chamber 10 is an 
inverted microscope chamber with it to be understood that the present 
invention is not limited thereto and is applicable to an upright 
microscope chamber as well. The live cell chamber 10 includes an upper 
chamber frame unit 12 shown diagrammatically in FIG. 1 and in more 
specific detail in FIG. 2 and 3, the chamber frame unit being disc- or 
circular-shaped having formed therearound four generally identically 
shaped radially extending uniformly spaced recesses or notches 14 
generally arcuately spaced 90.degree. about the circumference of the 
chamber frame unit. Fluid ports 16 and 18 are provided for allowing 
infusion/perfusion and discharge of any desired culture medium through the 
chamber. The body of the chamber frame unit 12 is adapted to support a 
housing 19 for electrical connectors and the like for heaters and 
temperature sensors arranged within the confines of the assembled live 
cell chamber 10. The chamber frame unit 12 is also provided with an 
enlarged central operature 20, and is generally shaped to mate with a 
disc-shaped, generally circular support base unit or chamber base unit 30 
of greater diameter than that of the chamber frame unit 12, for supporting 
and housing the remaining elements of the live cell chamber 10. 
The chamber base unit 30 mated or coupled with the chamber frame unit 12 
will house an upper seal 32, cover slip window or infusion/profusion unit 
34, a lower gasket 36, and another cover slip window referred to as cover 
slip 38, with these units, as shown in FIG. 1 and diagrammatically in FIG. 
12 being constructed and arranged to form an infusion/perfusion chamber in 
communication with the infusion/perfusion ports 16 and 18. My U.S. Pat. 
No. 4,974,952 earlier referred to clearly describes the function of the 
infusion/perfusion chamber and such description is incorporated herein by 
reference. 
The present invention lies in the securing and locking assembly 40 for 
locking the chamber frame unit 12 with the chamber base 30, and includes a 
ring shaped upper unit 42 formed with machine threads on the outer 
periphery thereof, and four identically shaped equally arcuately spaced, 
upwardly, axially extending L-shaped fingers 44, each pair being spaced 
90.degree. apart. The upper unit 42 is threaded into a ring shaped lower 
base member 50 having complementary internal threads formed on its 
interior periphery. The assembled upper unit 42 and lower base member 50 
are rotatably received on the outer radial portion of the chamber base 
unit 30 as is shown in FIG. 12. When assembled with the chamber base unit 
30, the upwardly extending fingers 40 of the securing and locking assembly 
40 extend through arcuately spaced axially extending openings 54 which are 
axially aligned with the notches 14 formed on the chamber frame unit 12, 
with the fingers 44, in turn, extending through the opening 54 into radial 
alignment outside the notches 14. The fingers 44 and the notches 14 are 
sized and shaped such that the radially extending portions of the fingers 
44 will engage the upper surfaces of the chamber frame unit 12 when the 
upper unit 42 is rotated relative to the lower base member 50. The 
circumferential lengths of the openings 54 are greater than the 
circumferential lengths of the notches 14 for the reason to be understood 
as this description continues. The relative rotation of the upper unit 42 
and lower base member 50 will occur as follows: when desiring to secure 
and lock the chamber frame unit 12 and chamber base 30 together the lower 
base member 50 will be rotated by hand, carrying with it the upper unit 42 
until the upwardly extending portions of the fingers 44 engage the axial 
surfaces of the openings 54 thereby stopping the rotations of the upper 
unit 42 with the lower base member 50 continuing to be rotated on the 
threads between the upper unit 42 and the lower base member 50 whereby the 
entire upper unit 42 will translate axially downwardly and the radial 
portions of the fingers 44 will engage upper portions:of the chamber frame 
unit 12. The result will be that the chamber frame 12 and the chamber base 
30 will be secured and locked to each other. When the fingers 44 engage 
the sides of the openings 54 the fingers 44 will be positioned arcuately 
beyond the notches 14 and in a position to engage upper surface portions! 
of the chamber frame unit 12. To disengage the chamber frame unit 12 and 
chamber base 30, the lower base member 50 is rotated in the opposite 
direction and will translate axially upwardly on the threads between the 
upper unit 42 and the lower base member 50 raising the fingers 44 above 
the chamber frame 12, and thereafter both the lower base member 50 and 
upper unit 42 will rotate as a unit to position the fingers 44 relative to 
the notches 14 such that the chamber frame 12 and chamber base 50 are in 
position to be separated. 
FIGS. 6, 11 and 12 show a base ring 60 shaped and sized to fit into an 
annular channel formed in the lower portion of the chamber base 30. The 
base ring 60 is secured to the chamber base 30 by machine bolts, not 
shown, and secures in place the securing and locking assembly 40 with the 
chamber base 30. 
FIG. 12 is somewhat diagrammatic and is exploded in its representation, 
with the elements of the live cell chamber 10 being separated for 
description purposes only. In actuality when the elements of the live cell 
chamber 10 are assembled the inner elements are snugly operatively engaged 
to form an infusion/profusion chamber with the infusion/profusion fluid 
ports 16 and 18 communicating with the chamber. 
The chamber base 30 is also formed to receive a toroidal shaped heater 
element 70 which may be electrically activated to provide controlled heat 
energy as desired to the assembly. 
The securing and locking assembly 40 is simply hand operated and provides 
positive and uniform clamping and locking of the chamber base 30 to each 
other. The internal elements, and in particular the fragile 
infusion/profusion unit 34 and cover slips 38, are protected against 
damage and misalignment between engaged elements avoided to preserve 
sealing therebetween. 
It should now be clearly recognized how the present invention overcomes the 
drawbacks of the heretofore method and means of securing chamber frame 
units and chamber bases together. Other modifications to the elements 
forming the present invention might also be recognized be those skilled in 
this art. Those skilled in this art should also understand that this 
invention is applicable to any live cell chamber and is not limited to my 
live cell chamber described and claimed in my U.S. Pat. No. 4,974,952. The 
recitation of the elements in the claims hereof are intended to apply to 
any live cell chamber. 
While I have shown and described a present preferred embodiment of this 
invention,: it is to be distinctly understood that the invention is not 
limited thereto, but may be otherwise embodied within the scope of the 
following claims.