U.S. patent number 3,589,557 [Application Number 04/813,063] was granted by the patent office on 1971-06-29 for slide dispenser.
This patent grant is currently assigned to Miles Laboratories, Inc.. Invention is credited to Leighton Clifford Johnson.
United States Patent |
3,589,557 |
Johnson |
June 29, 1971 |
SLIDE DISPENSER
Abstract
Apparatus is provided for dispensing rectangular platelike
objects, such as microscope slides, one at a time. This dispenser
also provides means for producing desirable liquid smears on
microscope slides. A supporting track is located along the top of
the dispenser for supporting a slide having a blood drop, for
example, on its lower face. A stored slide protrudes from a storage
magazine and forms an acute angle with the plane of the supporting
track. The leading edge of the protruding slide projects slightly
above the plane of the supporting tract and is capable of being
depressed so as to be in the same plane as the supporting tract.
The slide having the blood drop is moved in one direction along the
track in depressing engagement with the leading edge of the
protruding slide until the blood drop on its under side contacts
said protruding slide and forms a liquid capillary meniscus in the
acute angular space between the two slides. The slide having the
blood drop is then moved along the supporting track in the opposite
direction to spread out the liquid along the lower surface of such
slide and form a desired liquid smear.
Inventors: |
Johnson; Leighton Clifford
(Edwardsburg, MI) |
Assignee: |
Miles Laboratories, Inc.
(Elkhart, IN)
|
Family
ID: |
25211361 |
Appl.
No.: |
04/813,063 |
Filed: |
April 3, 1969 |
Current U.S.
Class: |
221/95; D16/236;
118/100; 221/279 |
Current CPC
Class: |
G02B
21/34 (20130101) |
Current International
Class: |
G02B
21/34 (20060101); A24f 027/14 () |
Field of
Search: |
;221/135,199,1,22,279,285,303,304,307 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Coleman; Samuel F.
Claims
What I claim is:
1. Apparatus for storing and dispensing rectangular platelike
objects, such as slides, having substantially flat upper and lower
surfaces and substantially straight end edges, which apparatus
comprises a magazine having a boxlike cavity capable of storing a
plurality of such objects in stacked relation, means in said cavity
biasing the topmost object stacked therein to a predetermined
position, said magazine also having an opening positioned to permit
said topmost object to be withdrawn from said cavity by endwise
movement, means for preventing more than said topmost object from
being withdrawn from said cavity when said topmost object is
withdrawn through said opening, supporting track means adjacent
said opening adapted to receive and support one of said objects for
longitudinal movement therealong, said track means and cavity being
positioned such that one of said objects when placed flat against
said track means has its lower surface engaged by an end edge
portion of the topmost of any objects stacked in said cavity and
forms an acute angle with the upper surface of said topmost
object.
2. Apparatus according to claim 1 wherein said end edge portion of
said topmost object normally projects slightly above the plane of
said track means and is depressable against said biasing means into
said plane by slight downward pressure on said object on said track
means.
3. Apparatus according to claim 1 wherein the acute angle between
the upper surface of the topmost object in the cavity and the lower
surface of an object placed flat along said supporting track means
is from about 10.degree. to about 20.degree..
4. Apparatus according to claim 3 wherein the acute angle is about
15.degree..
5. Apparatus according to claim 1 wherein the means for preventing
withdrawal of more than the topmost object from said cavity is
adjustable to compensate for variations in object thickness.
6. Apparatus according to claim 1 wherein said cavity is defined by
a bottom plate portion, a top plate portion, and two substantially
parallel end wall portions which have planes which are
substantially normal to the planes of the bottom and top plate
portions, and said biasing means comprises a pressure plate having
a substantially flat upper surface and which is capable of sliding
movement along and between said end wall portions and a compression
spring located between said bottom plate portion of said cavity and
the pressure plate, the objects stored in said cavity being located
between the substantially flat upper surface of the pressure plate
and the top plate portion of the cavity, the pressure of said
compression spring against the pressure plate being operable to
force the topmost stored object against said top plate portion and
position said end edge of said topmost stored object slightly above
the plane of the supporting track means.
7. Apparatus according to claim 6 wherein the cavity has an open
side for insertion of objects into said cavity and wherein there is
releasable retention means for retaining the pressure plate in a
position in which the compression spring is substantially fully
compressed to thereby facilitate insertion of objects into said
cavity.
Description
BACKGROUND AND PRIOR ART
It is well known in the art that microscope slides should be as
clean as possible, i.e., free of surface dirt and fingerprints,
prior to use in the preparation of liquid smears, for example, for
subsequent microscopic examination. Microscope glass slides are
generally available in clean form in original packages, but they
become dirty, especially with fingerprints, when they are removed
from such packages and handled prior to microscopic examination.
This is especially true when the glass slides are employed to
prepare liquid smears, such as blood smears.
There have been various efforts in the prior art to provide
mechanical dispensers for dispensing clean slides, but these
efforts have not been commercially successful, especially for the
dispensing of slides one at a time.
It is also well known in the art that liquid smears, such as blood
smears, on a microscope slide are generally prepared in the
following manner. A drop of blood is applied to the upper surface
of a first glass slide near one end of the slide. A second glass
slide having a substantially straight leading edge is positioned
over the first slide with the leading edge of its lower surface in
contact with the blood drop and the upper surface of the first
slide and with the plane of the lower surface of the second slide
forming an acute angle with the plane of the upper surface of the
first slide. The blood drop forms a liquid capillary meniscus in
the acute angular space between the two slides. The second slide is
then moved along the first slide with the liquid-containing acute
angular space in a trailing position. This forms a liquid smear
along the upper surface of the first slide. This prior art manual
procedure has the disadvantage that the production of a high
quality liquid smear is dependent upon the maintenance of a proper
liquid capillary meniscus in the acute angular space between the
two slides during the formation of the liquid smear. In this manual
operation the maintenance of the desired acute angle is dependent
primarily on the dexterity of the person handling the slides. The
uniformity of consecutive liquid smears made by the same operator
is often of a low order and between liquid smears made by different
operators can be even worse.
OBJECTS AND SUMMARY OF THE INVENTION
It is an object of the present invention to provide improved
apparatus for dispensing rectangular platelike objects, such as
microscope slides.
It is another object of the present invention to provide apparatus
for the production of consistent acceptable quality liquid smears
on slides.
In accordance with the present invention, apparatus for storing and
dispensing rectangular platelike objects, such as slides, having
substantially flat upper and lower surfaces and substantially
straight end edges is provided which comprises a magazine having a
boxlike cavity capable of storing a plurality of such objects in
stacked relation, means in said cavity biasing the topmost object
stacked therein to a predetermined position, said magazine also
having an opening positioned to permit said topmost object to be
withdrawn from said cavity by endwise movement, means for
preventing more than said topmost object from being withdrawn from
said cavity when said topmost object is withdrawn through said
opening, supporting track means adjacent said opening adapted to
receive and support one of said objects for longitudinal movement
therealong, said track means and cavity being positioned such that
one of said objects when placed flat against said track means has
its lower surface engaged by an end edge portion of the topmost of
any objects stacked in said cavity and forms an acute angle with
the upper surface of said topmost object. The end edge portion of
said topmost object normally projects slightly above the plane of
said track means and is depressable against said biasing means unto
said plane by slight downward pressure on said object on said track
means.
When a slide having a drop of liquid depending from its lower
surface is placed on said supporting track and is moved so that the
liquid contacts the upper surface of the slide projecting from the
magazine, a liquid capillary meniscus is formed in the acute
angular space between the upper surface of the projecting slide and
lower surface of the slide on said tract. Subsequent longitudinal
movement of the slide on said track along and flat against said
supporting track is effective to cause the liquid to be spread out
over the lower surface of the supported slide and form a desired
liquid smear thereon.
DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of the assembled dispenser of the
present invention shown containing slides to be dispensed;
FIG. 2 is a side view with a portion removed of the slide magazine
unit removed from the assembly of FIG. 1;
FIG. 3 is a plan view of the magazine unit of FIG. 2;
FIG. 4 is an end view of the magazine unit taken along line 4-4 of
FIG. 2;
FIG. 5 is an end view of a portion of the magazine unit taken along
line 5-5 of FIG. 2;
FIG. 6 is a partial cross-sectional view taken along line 6-6 of
FIG. 3 showing the relationship between two slides and a drop of
liquid contained therebetween at the start of the preparation of a
liquid smear on one of the slides;
FIG. 7 is a similar view to FIG. 6 showing the partially formed
liquid smear; and
FIG. 8 is a side view similar to FIG. 2 showing a portion of the
magazine unit having a preferred apparatus configuration.
DESCRIPTION OF THE INVENTION
Referring to FIG. 1, the dispenser of the present invention
comprises a rectangular boxlike case 10, an attached base 12, and a
magazine unit 14, shown in more detail in FIG. 2, which is
removably positioned within case 10. Case 10 as shown has vertical
sidewalls 16 and 18 and vertical end walls 20 and 22. A notched
portion 17 is cut out of the upper edge of sidewall 16 as shown in
FIG. 1. A corresponding notched portion 19 is cut out of sidewall
18 directly opposite the notched portion 17. A slanted slot 21 is
also cut through sidewall 16. Base 12 has spaced parallel
upstanding ribs 24 and 26 forming a channel 28 therebetween. Case
10 is positioned within channel 28 and is attached to the base 12
by suitable means. Base 12 also has flange portions 30 and 32
extending laterally outwardly from ribs 24 and 26 respectively.
Flange portions 30 and 32 terminate in longitudinal rib members 34
and 36 respectively of T-shaped cross section.
The removable magazine unit 14 is shown in detail in FIGS. 2, 3 and
4. Magazine unit 14 has parallel rectangular sidewalls 38 and 40.
Sidewall 38 has a rectangular opening 50 formed therein. At
opposite side margins of said opening 50 parallel transverse end
walls 42 and 44 are bent inwardly from wall 38 toward sidewall 40
and are joined by welding, for example, to sidewall 40. Along the
bottom margin of the opening 50 a transverse bottom plate 46 is
bent inward from sidewall 38 toward sidewall 40 and is also
attached by welding, for example, to sidewall 40. Bottom plate 46
is provided with an upstanding pin 52 as shown. An angled top plate
member 48 has one leg thereof attached to the upper edge portion of
end wall 44 and another leg thereof extending parallel to bottom
plate 46 as shown. The planes of bottom plate 46 and top plate 48
are normal to the planes of the end walls 42 and 44. A rectangular
boxlike magazine cavity 51 is thus formed having end walls 42 and
44, bottom plate 46, top plate 48, closed sidewall 40 and an open
side 50 formed in sidewall 38. Apertures 53 and 55, as shown in
FIG. 2, are formed in sidewall 40 near the two lower corners of
cavity 51.
Cavity 51 is tilted with respect to magazine unit 14 so that end
walls 42 and 44 are from about 10.degree. to about 20.degree.,
preferably about 15.degree., from the vertical, and parallel bottom
and top plates 46 and 48 are from about 10.degree. to about
20.degree., preferably about 15.degree., from the horizontal. A
channel-shaped pressure plate 57 having an elongated rectangular
substantially flat upper surface portion 54 and depending end
flanges 56 and 58 is located in the cavity. Upper surface portion
54 is substantially parallel to bottom and top plates 46 and 48 and
end flanges 56 and 58 are substantially parallel to end walls 42
and 44. As shown in FIG. 5, the flange 58 has a hook portion 59
formed therein. Flange 56 has a similar hook portion. The pressure
plate 57 is positioned in the cavity 51 in such manner that the the
hook portions of the end flanges 56 and 58 are adjacent to sidewall
40. The pressure plate 57 is capable of sliding movement within
cavity 51 along and between the end walls 42 and 44 thereof.
Pressure plate portion 54 has a vertically depending pin 60
attached thereto.
A single leaf pleated compression spring 62 having an upper
aperture 64 and a lower aperture 66 therein is placed in the cavity
51 between portion 54 of the pressure plate 57 and bottom plate 46
with the pin 60 of pressure plate portion 54 extending through
upper aperture 64 and the pin 52 of bottom plate 46 extending
through lower aperture 66. Compression spring 62 thus biases the
pressure plate 57 upwardly toward the top plate 48. The cooperation
between pins 52 and 60 and apertures 64 and 66 tends to keep the
pressure plate 57 and compression spring 62 within the cavity
51.
A first supporting track member 68 is located along the top of
magazine unit 14 and is attached thereto between sidewalls 38 and
40 in a manner to be described hereinafter. Member 68 has a
generally U-shaped transverse cross section with a flat bottom wall
portion 70 and stepped side portions 72 and 74 shown in FIGS. 1 and
3. The side portions 72 and 74 are formed with elongated spaced
parallel coplanar supporting track surfaces 76 and 78,
respectively, elongated spaced parallel coplanar top surface
portions 80 and 82, respectively, and coplanar inclined top surface
portions 92 and 94, respectively. Member 68 has an outer end
surface 84 and a narrower inner end surface 86. Inclined top
surface portions 92 and 94 intersect the upper surface of bottom
portion 70 at inner end surface 86. Coplanar supporting track
surfaces 76 and 78 intersect inclined surface portions 92 and 94
along edges 96 and 98, respectively. Track member 68 also has
parallel side surface portions 100 and 102 and converging side
surface portions 104 and 106. Side surface portions 100 and 102
extend in a longitudinal direction from outer end surface 84 for a
distance equal to the longitudinal dimension of top surface
portions 80 and 82, and converging side surface portions 104 and
106 extend longitudinally from the inner end surface 86 a distance
equal to the longitudinal dimension of the inclined surface
portions 92 and 94. Elongated longitudinal parallel slots 88 and 90
extend inwardly along the undersurface of side portions 72 and 74
respectively as shown in FIG. 1.
A second supporting track member 108 is also located along the top
of magazine unit 14 between sidewalls 38 and 40 and is spaced from
and aligned with the first supporting track member 68. Member 108
also has a generally U-shaped transverse cross section, as viewed
in FIGS. 1, 3 and 4, with a flat bottom wall portion 110 and
stepped side portions 112 and 114. The side portions 112 and 114
are formed with elongated spaced parallel coplanar supporting track
surfaces 116 and 118, respectively, and elongated spaced parallel
coplanar top surfaces 120 and 122, respectively. Elongated
longitudinal parallel slots 91 and 93 extend inwardly along the
undersurface of side portions 112 and 114 respectively as shown in
FIGS. 1 and 4. Member 108 has an outer end surface 124 and an inner
end surface 126. A lower portion of inner end surface 126 is cut
away to form a flat inclined surface 127 which is disposed at an
angle of from about 10.degree. to about 20.degree., preferably
about 15.degree., from the supporting track surfaces 116 and 118.
This is shown in FIG. 2. Supporting track surfaces 116 and 118 are
slightly widened near the inner end surface 126 by divergent
surfaces 128 and 130 which cut through side portions 112 and 114
between top surfaces 120 and 122 and track surfaces 116 and 118.
Track surfaces 76 and 78 of the first supporting tract member 68
are coplanar respectively with track surfaces 116 and 118 of the
second supporting track member 108.
The second supporting track member 108 is conveniently attached to
magazine unit 14 in the following manner. Indent portions 132 and
134 are partially cut out of sidewalls 38 and 40 respectively and
indented as shown in FIG. 4. Appropriate slots, such as slot 136,
shown in FIG. 2, are formed in the indent portions 132 and 134 to
receive the opposite end portions of a flat transversely extending
bar 138 having a centrally located threaded aperture 141 formed
therein. A screw 140 passing transversely through an appropriate
passage in the bottom wall portion 110 of member 108 may be
threaded into the aperture 141 to secure member 108 in place.
Alternatively, as shown in FIG. 4, screw 140 can be of a size to
pass freely through the aperture 141 and be threaded into a nut 142
positioned below the bar 138. When supporting track member 108 is
attached to magazine unit 14, sidewalls 38 and 40 extend into the
elongated longitudinal slots 93 and 91 respectively as shown in
FIG. 4.
The first supporting tract member 68 can be attached to the
magazine unit 14 in a similar manner. As shown in FIG. 2, with a
portion of sidewall 38 removed, a screw 144 is threaded through a
threaded aperture in bar 146 the ends of which respectively fit
into appropriate slots such as slot 148 of indent portion 150 of
sidewall 40. The opposite end of bar 146 fits into a similar slot
(not shown) in sidewall 38. When supporting track member 68 is
attached to magazine unit 14, sidewalls 38 and 40 extend into the
elongated slots 90 and 88 respectively of member 68.
Supporting track members 68 and 108 are longitudinally spaced from
each other along the top of magazine unit 14 so as to form an
opening 152 therebetween which communicates with cavity 51.
Abutment means consisting of a generally V-shaped member 154 of
flat spring stock has an upturned abutment portion 158 which
extends into opening 152 and terminates adjacent and parallel with
the inner end surface 86 of member 68. Member 154 is located as
shown in FIG. 2 with one leg thereof underlaying the bottom surface
of member 68 and with supporting screw 144 passing through
appropriate apertures in member 154. As shown in FIG. 2, a knurled
nut 156 is threaded onto screw 144 and compressively engages the
V-shaped portion of member 154. Rotational movement of nut 156
adjusts the vertical position of the abutment portion 158, the
upper edge of which is preferably adjacent to and slightly below
the plane of coplanar surfaces 76, 78, 116 and 118 of track members
68 and 108.
The improved dispenser apparatus of the present invention is filled
with microscope slides in the following manner. Magazine unit 14 is
removed vertically from case 10. Pressure plate 57 is depressed
toward bottom plate 46 against the pressure of spring 62 until the
hook portions 59 of the flanges 56 and 58 engage in the apertures
53 and 55 of sidewall 40 near the bottom of cavity 51. Engagement
of the hook portions 59 in said apertures holds the pressure plate
in the loading position. A box of clean microscope slides is opened
and the clean slides, generally about 60--65 slides, are placed
into the cavity by stacking them on top of each other in
face-to-face relation. During this stacking care should be taken to
handle the slides on their edges only, thus minimizing the chances
of placing fingerprints on the faces of the slides. When the cavity
is fully loaded, the hook portions 59 of the pressure plate 57 are
disengaged from apertures 53 and 55 whereupon the compression
spring 62 expands, forcing the pressure plate 57 against the slides
and forcing the slides against the top plate 48 and against the
inclined undersurface 127 of second track member 108. The uppermost
slide 160 in the magazine cavity then protrudes into opening 152
and can abut against the portion 158 of abutment member 154. The
substantially straight end edge 164 of the uppermost slide 160 is
then positioned slightly above the plane of coplanar surfaces 76,
78, 116 and 118. Slide 160 now forms an acute angle of from about
10.degree. to about 20.degree., preferably about 15.degree., with
the plane of the above coplanar surfaces. The magazine unit 14 is
then placed into case 10 as shown in FIG. 1.
To remove a slide from the dispenser the side surfaces 165 and 166
of the uppermost slide 160, as shown in FIG. 1, are grasped between
two fingers and said slide is pulled up and out. Notches 17 and 19
in sidewalls 16 and 18 of case 10 enable the side surfaces of the
uppermost slide to be exposed for ease in removal. The reduced
width of the inner end 86 of track member 68 also facilitates
access to the slides. As long as the upper edge portion 158 of
abutment member 154 is located along the leading end surface 163 of
the slide 160 while it is stored in the magazine, it will abut
against the next below slide 162 and prevent it from being removed
during withdrawal of slide 160 from the dispenser. Abutment member
154 is adjusted by nut 156 to achieve this condition and such
adjustment permits slides of various thicknesses to be used in the
improved dispenser.
In FIG. 2, slide 160 is shown being withdrawn over the top of the
abutment portion 158 of member 154 while the remaining slides are
maintained within the magazine. This apparatus thus provides means
for dispensing slides one at a time. Once slide 160 is completely
removed, spring 62 will force the next slide 162 into the uppermost
position for subsequent removal. This procedure is repeated every
time a slide is withdrawn from the dispenser. The slanted slot 21
in sidewall 16 of case 10 exposes a portion of the interior of
magazine 14 to view and allows one to determine how many slides are
available for use before the magazine needs refilling.
This improved dispenser apparatus can be used to prepare uniformly
desirable liquid smears on slides, and in such use, the coplanar
surfaces 76, 78, 116 and 118 of supporting track members 68 and 108
provide a supporting track which engages longitudinal edge portions
only of the lower surface of a slide placed therein. As shown in
FIG. 6, a slide 168 having a liquid drop, such as a blood drop,
applied to one surface thereof generally along the longitudinal
centerline is placed on the above-described supporting track with
the liquid-bearing surface thereof facing downwardly and with the
liquid drop on the right hand side of the leading edge 164 of
uppermost slide 160 stored in the magazine, as viewed in said FIG.
The leading edge 164 of uppermost slide 160 is then in contact with
lower surface 170 of slide 168. Slide 168 is then moved to the
left, as viewed in FIG. 6, until the depending liquid drop contacts
slide 160 and forms a liquid capillary meniscus 172 in the acute
angular space formed between the protruding slide 160 and the lower
surface 170 of the supported slide 168. Slide 168 is then moved to
the right, as shown in FIG. 7, with the simultaneous application of
a light downward pressure sufficient to depress the leading edge
164 of the uppermost slide 160 into substantially the same plane as
the supporting surfaces 76, 78, 116 and 118. Such longitudinal
movement of the slide 168 spreads out the liquid along lower
surface 170 thereof and forms a desirable liquid smear 174. The
slanted surfaces 128 and 130 of member 108 guide the slide 168 onto
the supporting track surfaces 116 and 118 during such slide
movement. This apparatus is capable of producing uniformly
acceptable liquid smears, because it provides a substantially
constant angle between the lower surface of the supported slide and
the upper surface of the coacting protruding slide. This
substantially constant angle, which is predetermined to be from
about 10.degree. to about 20.degree., preferably about 15.degree.,
has been found to be most satisfactory for the production of
acceptable liquid smears.
Slide 168 is generally moved to the right, as viewed in FIG. 7, for
a sufficient distance to enable all of the liquid contained in the
acute angular space between slides 168 and 160 to be spread along
undersurface 170 of slide 168. In the event that all the liquid is
not spread along slide 168, any liquid residue remaining on the
upper surface of slide 160 will not interfere with subsequent use
of slide 160 so long as it is withdrawn from the dispenser and its
leading edge portion is not subsequently employed for the
production of another liquid smear.
Once the liquid smear is applied to slide 168, it is then removed
from the supporting track and dried. The configuration of the
apparatus of the present invention also aids in drying of applied
smears. To this end the slide 168 bearing the liquid smear can be
leaned against a sidewall of the case 10 with its lower end portion
rested against a longitudinal rib 34 of the base 12. This is shown
in phantom in FIG. 1.
A preferred form of the abutment means is shown in FIG. 8. A
threaded shaft 49 is fixed to and projects generally normal to
cavity end wall 42'. A bowed spring member 47 having substantially
flat opposite end portions 41 and 45 and a generally centrally
located aperture 39 is positioned with said end portions in contact
with the end wall 42' and the threaded shaft 49 extending through
aperture 39. Lower end portion 45 of spring member 47 is attached
to the end wall 42' near the lower end thereof by welding, for
example. Upper end portion 41 of spring member 47 has an outer edge
35 positioned subjacent the plane of supporting track 78' of track
member 68'. A knurled nut 33 is threaded onto shaft 49 and
compressively engages spring member 47 as shown. As nut 33 is
rotated inwardly along the shaft 49, it depresses spring member 47
and causes edge 35 to move upward as shown in FIG. 8. If nut 33 is
rotated so that it moves outwardly along the shaft 49, it relaxes
member 47 and allows edge 35 to move downward. This movement of
outer edge 35 achieves the same function as similar movement of
outer edge portion 158 of abutment member 154 described above.
* * * * *