Note: Descriptions are shown in the official language in which they were submitted.
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BACKGROUND OF T~IE IN~IENTION
This application relates to the freezing of fish into
blocks and in particular to a pan or frame in which fish are
packed and frozen as well as to means for ejecting a frozen
block of fish from the frame.
There are many current methods of freezing fish. Large
and increasing tonnages of fish must be quickly converted to
the frozen state for sale either directly to a consumer market
or to processors who convert the frozen product into various
forms for subsequent, consumer use. One sector of this market
which serves as a primary product to processors is frozen fish
blocks and these are generally made up in sixteen and a half to
eighteen and a half pound rectangular blocks. The blocks are
manufactured to predeter~ined rectangular sizes and thicknesses
and to predetermined weights.
Fish processors gear their process of cutting of
blocks to the specified dimensions and depend upon the
manufactured block being supplied consistently to the specified
dimensions for efficient yields and profitability. If the
frozen blocks coming from the manufacturer vary from the
processor's specifications, it is not uncommon for losses of
up to six percent to occur. Accordingly, the increased value
of the fish blocks has led to greater insistence on adherence
to specifications to avoid such losses.
Conventionally, frozen fish blocks have been
manufactured by filling aluminium pans with fish and then
freezing them in plate type pressure freezers. These
conventional pans, fabricated from aluminium plate, are
subjected to abuse during processing and can only hold their
dimensional stability for a very short period of time. This
results in t~e blocks in the pans being formed outside of the
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specifications mentioned above. Efficiency drops and losses
occur. Furthermore, it is difficult to remove the frozen blocks
of fish from conventional pans.
SUMMARY OF THE INVENTION
The present invention provides a design of a fish
freezing frame which is unique in its method of manufacture
and in its structure and it provides dimensional stability to
retain consistent specified dimensions to the frozen fish
blocks; an economic life due to its structural superiority over
conventional frames; and easy removal of the frozen block from
the frame after freezing.
The freezer frame is manufactured from extruded
aluminium and due to the configuration of the side walls and
floor of the freezer frame and the characteristics of
contracting metal when cooled together with the expansion of
the moisture content of the fish frozen in the frame, a self
ejection tendency is provided when the pressure is released
subsequent to freezing. Apparatus is also disclosed for
ejecting the frozen block from the freezer frame and this
consists of a manually or automatically operated press which
receives an inverted freezer frame with a frozen block of fish
therein and, when actuated, applies an external force to the
bottom of the frame to deflect the bottom without subjecting
the frame to permanent distortion.
According to one broad aspect the invention relates to
a fish freezing frame comprising a bottom and upwardly
extending side and end walls. At least one parallel pair of
the walls are extruded integrally with the bottom and
longitudinally extending, outwardly directed flanges are
?rovided on the top and bottom edges of the side and end wall~.
The side walls are tapered out~ardly from the bottoms to the
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tops thereof.
In accordance with another aspect, the invention
relates to a fish product freezing frame comprising a
bottom and upwardly extending side and end walls; at least
one parallel pair of said walls being extruded integrally
with said bottom; longitudinally extending outwardly
directed flanges on the top and bottom edges of said side
and end walls, said side walls being tapered outwardly
from the bottoms to the tops thereof; and a plurality of
apertures in the bottom of said frame to allow the ingress
Gf air into the bottom of the frame for ejecting a block
of product therefrom.
In accordance with another aspect, the invention
relates to in combination, a fish product freezing frame and
means for ejecting a frozen block of product from said
frame; said product freezing frame comprising a bottom and
upwardly extending side and end walls; at least one parallel
pair of said walls being extruded integrally with said bottom;
longitudinally extending outwardly directed flanges on the
top and bottom edges of said side and end walls, said side
walls being tapered outwardly from the bottoms to the tops
thereof; said ejecting apparatus comprising means for
supporting the freezer frame in an inverted position and
an opening in said supporting means corresponding in
size to that of said product block; and means for applying
pressure to the bottom of said frame to effect ejection of
the block from the frame.
BRIEF DESCRIPTION OF THE DRAWINGS
The invention is illustrated by way of example in the
accompanying drawings in which:
Figure 1 is an isometric view of a freezer frame
according to the invention;
Figure 2 is a fragmentary, cross-sectional view of a
portion of the freezer frame in Figure l;
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Figure 3 is a front elevation of the apparatus for
ejecting fish blocks from freezer frames;
Figure 4 is a cross-sectional view taken along the
line 4-4 of Figure 3;
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Figure 11 is a side view of an upper elevating member
used in the apparatus; and
Figure 12 is a side view of a loT~er elevating member
used in the apparatus.
Referring to Figures 1 and 2, the fish freezing frame
lO has a bottom wall 12, side walls 14 and end walls 16. The
bottom 12 and the side walls 14 are extruded in one piece in
an aluminium extrusion method, the end walls 14 being
tapered outwardly at their top ends as shown at T in Figure 2.
In like fashion, end walls 16 are tapered outwardly at their
top ends relative to the bottom 12 of the frame but the end
walls are separate units as shown in Figure 1 and are welded
in place and in such a manner that weld metal penetration
provides crevice free ends. It will be apparent from Figure 2
that the "one piece" construction of the side walls and
bottom eliminates crevices which tend to cause cleaning
problems in this art.
Both of the side and end walls 14 and 16 respectively
are provided with longitudinally extending, outwardly
directed flanges 18 on their top ends and similar flanges 20
on their lower ends, these flanges resulting in substantial
improvements in the ability of the freezer frame of the
present invention to endure abuse during processing and
specifically to substantially increase the dimensional
stability of the frame compared with conventional devices.
While not necessary, it is advantageous to extrude
the bottom 12 of the frame in a maximum depth of about four
millimeters. When used with an ejector as illustrated in
Figures 3 through 6 of this application, it has been found
that a ^reezer pan having a bottom of this th~ckness allows
deflection thereof to a maximum of about one quarter of an
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inch without subjecting the frame to any permanent ~istortion.
The preferred amount of taper of the side walls of
the frame is 1 with a manufacturing tolerance of +112 -0
while the end walls also have a taper of 1 but with a
tolerance of +1-0~.
After a frame such as 10 in Figure 1 has been packed
with fish and frozen, the contraction of the metal combined
with the expansion of the frozen block of fish provides a
self ejection tendency along the upwardly and outwardly
tapering side walls 14. The predetermined taper shown in
Figure 2 which is extruded into the side walls, provides this
lifting tendency which substantially reduces the time and
force required to eject the block. from the pan.
Referring to Figures 3 through 6 inclusive, the
apparatus 22 for ejecting a frozen fish block from the freezer
frame such as that shown at 10 in Figure 1, comprises an
open topped table 24 supported by a plurality of legs 26, a
gantry or box frame 28 includes a pair of spaced side members
30 and horizontal members 32 for supporting a pan deflecting
cylinder 34. The frame members 30 include guides 36 which,
together with pan stops 38, Figure 6, serve to locate the
pan 10 in the correct position over the opening ir. the table
surface as shown in Figures 3 and 4. It will be seen from
the sectional view of Figure 4 that in this location the
frozen product in the pan has a free drop through the top of
the table.
The pan deflecting cylinder 34 is shown in full line
in its retracted position where its' deflecting head is in the
inoperative position, the operative position being shown at 42
in phantom line where it presses down on the bot-tom surface
of the pan o deflect it approximately l4 of an inch.
~ 'rame liftirg mechanism is shown in Figures 3-5
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and it includes a pair of rectangular, vertically oriented
members 44 positioned outside the general opening area of the
table top but located in recesses 48, Figure 6, of the table
area so that the members 44 can engage the flanges 46 of the
frame. Members 44 are supported on vertically oriented
actuating rods 50, the lower ends of which are pivotally
~ounted on a shaft 52. A pair of links 54 connect the shaft
52 with an actuating lever 56 of a pneumatic cylinder 58
mounted on one side of the machine as shown in Figure 5.
As shown in Figures 4 and 6, the table 24 is provided
with a pair of spaced knives. One end of the table includes
a fixed knife 60 mounted in a recess 62. The other, opposed
side of the table supports a horizontally movable knife 64
biased to the illustrated, open position by springs 66
mounted on rods 68. The latter members are actuated inwardly
by means of an actuating cylinder 70 mounted on the side of
the frame and being provided with an operating arm 72 the
outer end of which is secured to a rocker shaft 74 which
in turn actuates follower bars 76.
In operation, a frozen frame 10 and its contents are
placed manuallv into the machine in an inverted position as
shown in Figures 3 and 4 and being located properly by the
guides 36 and frame stops 38. The operator then depresses a
valve to institute a sequence of operations, the various
pneumatic components and circuitry associated therewith
following generally accepted industrial practice. Initially,
the frame deflecting cylinder 34 moves its piston downwardly
so that the nead 42 deflects the frame bottom as shown in
Figure 3 to push out .he frozen product block a distance of
appro~imatQl~ 4l OL- an inch. The return stroke of cylinder 3
initiates the kni~e cylinder 70 which in turn actuates the
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linkage 72, 74, 76 to actuate the movable knife 64 and the
product is securely held between the fixed and movable knives
64 and 60. Complete ejection of the frozen block from the
frame 10 is then accomplished by actuation of the frame lifting
cylinder 58 which causes the lifting members 44 to engage the
flange 46 of the frame 10 and to lift the frame upwardly
completely away from the product. The knives 60 and 64 are
then retracted, allowing the frozen product block to fall into
the angulated chute 80, Figure 4, and into some form of
receiving means.
It will be appreciated that the mechanism such as
cylinders 58 and 70 can be modified to accept hydraulic means
or a manual operation.
Samples of the freezer frame of the present
invention have been subjected to deflections for upwards of
thirty-five thousand cycles, the units being precisely
examined subsequently with no permanent distortion being
found.
Referring to Figure 7, a further embodiment of the
invention is illustrated in which pneumatic pressure is used
to eject the frozen product block from the frame, thereby
eliminating the mechanically assisted extraction of the block
from the frame as in the previously described embodiment.
In the embodiment of Figure 7, the frame containing the
frozen product is substantially the same as the frame 10 in the
previous embodiment but it will be seen from Figure 7 that
frame 90 has a plurality of apertures 92 in its bottom wall 94.
Air is forced into the apertures 92 under high pressure to
force the rrozen produce block from the frame.
Refer-ing to Figure 7, the ejection mechanism 96
includes a frame 98 having a pair of parallel, upper guide
rails 100 which de''ine ~n elongated path of travel (from right
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to left in Figures 7 and 8) for frames 90. Each frame is
fed manually or automatically onto the entry end 102 of the
apparatus and in the same manner is moved under an ejector
mechanism indicated generally at 104 where the frozen block
is forced out of the frame and the frame 90 is then moved
out to the exit end of the apparatus to subsequently drop
off the ends of the rails 100 onto a conveyor, bin or the
like. The frozen product block being lowered downwardly onto
a slide 106 to be conveyed away for processing.
The frames with the frozen block of product therein
can be fed manually beneath the ejection mechanism or an
automatlc feeding device can be used. The latter is illustrated
in Figures 7 and 8 and the feeding device incorporates a
pneumatic cylinder 108, the cylinder end of which is secured
to a cross member 110 bridging the rails 100, the piston end
of the cylinder 108 being connected to a frame pusher
consisting of a transverse blade 112 having side rails 114
wlth angled braces 116. It will be evident from Figure 8
that the side rails 114 serve to maintain the blade 112 in
proper alignment as it is reciprocated along the rails 100
by the cylinder 108. When using the automatic frame feeding
device, the individual frames enter the machine on an inclined
conveyor, not illustrated, onto the entry end 102 to strike
a switch 91 which activates the cylinder 108 so that ~he
blade 112 pushes the frame into the position illustrated in
Figure 7, immediately beneath the ejection mechanism 104.
The side rails 114 of the feeding mechanism blocks the entry
of another frame onto the entry end 102.
The ejection mechanism 104 includes a frame having
side rails 120 and a to? rail 122 and these together slidably
position a _rame co~er 124 to overlie the frame 90 as shown
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in Figure 7 and to mount the cover for vertical movement in
its frame. Such movement is effected by a further pneumatic
cylinder 126 which is connected to the cover 124 ~y palrs of
double link connections 128 at each end of the cylinder. It
will be evident from Figure 9 that actuation of the cylinder
126 will elongate the distance between its cylinder and piston
ends to bring the links 128 lnto alignment with one another
resulting in lowering of the cover 124 onto the frame 90.
Figure 7 shows that the cover 124 includes a soft resilient
gasket 130 around the inner periphery of the cover and, when
the cover 124 is lowered onto the surface of the frame 90,
the thi~kness of the gasket forms a sealed air cavity 132
between the bottom 94 of the frame and the cover 124.
Pressurized air is then fed into the cavity through a conduit
134 to effect movement of the frozen product block from the
frame 90 by entering the apertures 92 therein.
Means are provided for lowering the frozen product
block ejected from the frame onto the out rails 106 shown in
Figure 7. This elevating device consists of upper and lower
wedge-shaped members 136 and 138 respectively. The lower wedge
member 138 is reciproca-ted by an air cylinder 140 and as the
lower surface of wedge member 136 rests on and is supported by
the top surface of member 138, the upper member 136 is moved
to its lowermost position when member 138 is retracted by
cylinder 140 to its position shown at A in Figure 7 and is
raised to its uppermost position -~rthen member 138 is advanced
to its s position shown in Figure 7.
Referring to Figures 3 and 12, wedge member 138 is
provided with flanges 142 along each of its lower side ed~es
and these ensage rails 144 along the frame 98 and positioned
more or less directly below the rails 100 on the upper pa~t of
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369
the frame. The wedge member 138 has a sloping top surface 146
and the forward end of the member has a tongue 148 which is
connected to the rod end of cylinder 140. It will be
appreciated therefore that actuation of cylinder 140
reciprocates member 138 along the rails 144.
The upper elevating member is again formed in the
general shape of a wedge and includes a flat top surface 150
which, when the member 136 is raised to its uppermost position,
is coplanar with the surface 142 of the entrance end of the
apparatus so as to support the inverted frame 90 with the
frozen product therein. The lower surface 152 is sloped at
the same angle as upper surface 146 on member 138 and the
narrow end of member 136 has an elongated pin 154 secured
thereto, the ends of the pin extending out beyond the ends of
the mem~er and are enclosed in slideways 156 vertically mounted
on either side of the frame 98 below the tracks 100. See
Figure 10.
It will be evident from the above description that
with the elevating member 138 in its position B in Figure 7,
the upper member 136 is in position to receive the inverted
tray 90 as shown in Figure 7. As the member 138 is drawn
back, towards the position A, the weight of the upper member
136 together with the pressure applied to it by the cover 124
and the frozen product block from the tray 90, causes it to
be lowered downwardly with the ends of the pin 154 riding in
the slideways 156. When the pins reach their lowermost
position shown at point C in Figure 7, and with the lower member
138 in its fully retracted position at point ~, the forward
end of mem~er 136 will drop downwardly, pivoting around pins
1,4 so that the frozen block of product will slide out the
tracks 106.
When -the cover operating cylinder 126 starts air flow
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36~
into the cavity 132 between the cover 124 and the bottom wall
94 of the frame 90, the air pressure acting over the area of
the bottom of the frame 90 tends to deflect the bottom and
push the product out. ~owever, any such deflection is
prevented at this particular stage by the flat upper surface
150 of member 136. Accordingly, as pressure is maintained
between the ejecting product block and the flat top surface
150 of member 136, the block moves sufficiently under the
air pressure in cavity 132 to uncover the air holes 92 in the
bottom of the frame and the pressurized air then flows through
these holes and acts directly on the frozen block, continuing
to force it out of the frame 90. If there is any deflection
of the frame 90 at this point, the bottom of the frame will
now spring back to its original state as the pressure on the
bottom is equalized. By restricting the exhaust of the air
cylinder 140, the upper part 136 of the elevating device is
constrained to move downwardly in a vertical direction under
the force of the ejecting block and because of the pressure
being maintained between the two wedge-shaped members, block
alignment is maintained.
The cover operating cylinder 126 can be activated
either manually or by the cylinder 108 at the extension of
its stroke. Additionally, a further pressure signal from the
cover operating cylinder 126 starts air to flow into the cavlty
132 and a further air pressure signal is used from the cavity
to start the cylinder 140 moving in its retracting position
to lower the elevating member 136. When the blocX of frozen
product has been ejected from the frame 90 and is clear thereof,
the ejecting air supply is shut off by switch 158 being
contacted by ~he lower wedge-shaped member 138. Af'er the
upper member 136 pivots about point C, and the rrozen product
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369
is slid off through rails 106, switch 160 is contacted by the
frozen block which effects actuation of cylinder 140 to
return the elevating devices 136, 138 to their uppermost
positions; the raising of the cover plate by cylinder 126;
and the return of the air cylinder 108 to its Figure 8
position.
While the invention has been described in connection
with specific embodiments thereof and in specific uses,
various modifications ~hereof will occur to those skilled in
the art without departing from the spirit and scope of the
invention as set forth in the appended claims.
The terms and expressions which have been employed
in this specification are used as terms of description and
not of limitation, and there is no intention in the use of
such terms and expressions to exclude any equivalents of the
features shown and described or portions thereof, but it is
recognized that various modifications are possible within
the scope of the invention claimed.
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