FISHERIES RESEARCH BOARD OF CANADA
t
A MACHINE TO SLICE COD
FILLETS
BY
H.E.POWER
a
H.FOUGERE
NIW 81RI18
CIRCULAR
NO••
TECHNOLOG'ICAL STATION
HALIFAX
NOVA
8COTIA
OCTOBER 1960
A MACHINE TO SLICE COD Fn.LETS
. Experiments have shown ~~at a substantial increase in the efficiency of candl:tng cod fillets for parasites can be expected if the
fillets are first sliced longitudinally into slices 1/2 inch thick
before candling, as shown in Fig. 1. A machine to perfonn this task
of slicing the cod fillets into suitably sized slices has been designed and developed at this Stationo
The first machine designed hera is shown in Fig 20 It was a
large machine measuring approx:i.ma-tiely 7 ft long by 10 ft wi.de» and
was constrtlcted of aluminum and st(;l61.
0
'l'he cutting mechanism of th1.s ~jlicing machine lras a multipleband lmife, in which four Imivge wore crossed ·to form a figure It8lt.
Each knife made two cuts, on.e from left to right, and one from right
to left. Thus the tendency for the fillets to be pulled to either
side of the conveyor belt was eliminated.
The fillets were fed to the cutting mechanism by a 24-inch wide
white rubber conveyor belt. As the belt approached the kilives, it
turned downward at an angle of 45° in order that gravity could assist
the friction of the fillet on the conveyor belt in pushing the fillet
through the band knives. Water sprays were used both to lubricate the
band knives and to keep the conveyor belt free of parlicles of fish.
Hardened steel guides kept the lmives at the proper spacing. The
bearings used were standard ball bearings for the knife pulleys and
babbi t bearings for the conv'eyor system a
Tests on this machine were carried out in various fish plants in
Prince Edward Island and Nova Scotia. On the basis of the tests, it
was decided that this machine ws la!"g'sr than desirable and that a
smaller machine requiring leas maintenance to the cutting mechanism
would be advantageous in adapting the slicing machine to existing
cutting lines. Accordingly work was started on the design and construction of a more compact machine employing circular knives in place
of the previously used mult.iple-band l:.nives. This machine was the
prototype for the present fillet slicing m~chine. The following paragraphs contain a brief description of this machine, shown in Fig. 4
a.nd 5.
Frame
The frame of' the fillet slj.cing machine is
1
con~tr-Ilcted
ot two
STAINLESS STEEL BLADES
DRAWING SHOWING BLADE ARRANGEMENT ON
FILLET SLICING MACHINE
Fig. 2
(
Original fillet splitting machine
.
Fig. 3
-
Front view of fillet splitting machine showing
multiple crossed band knives.
4
sides cut from 1/4-inch-thick aluminum 6SSr alloy plate, mounted side
by side with front£) bottom, and rear panels bolted together with 2-inch
by 2-inch aluminum angle gussets.. This forms a box-like structure upon
which bearings, conveyor belt and knivesS! etc. are mounted. All jOints
are sealed with an aluminum~sphal t t.ype of cement and a drain pipe is
provided in the bottom to lead off water used for lubrication of knives
and clearing the conveyor belt •
.§t1IDd
l'he frame is Suppol'.'t ed on a single leg of 9-inch diameter aluminum
tubing which ,i s, in turn, "raIded to a base of aluminum plate. The height
of this stand is such tha.t the working surface of the feed conveyor belt
is 36 inches above floor level. The stand is bolted to the frame with
four aluminum bolts so that it can be removed for shipment.
Conveyor svst.ru:n
Two 8-inch wide white rubber conveyor belts are arranged as shown
in Fig. 50 The first, or feed, belt feeds the fillets tail first, skin
side down, into the rotating knives at a speed of 48 ft/min. The second
belt serves to remove the sliced fillets from the machine ~d convey
them either to another beltl} water troughS! or other containers. The
elevation angle of the discharge conveyor may be adjusted from horizontal
to a maximum of :3QO.
Both belts are driven from the same 1/4-hp totally enclosed gear
motor by two 1/2-inch pitch chain drives, one going to the drive pulley
of each conveyor. All shafts used in the conveyor system are of 18.8
alloy stainless steel.
The bearings used for the conveyor system are of stainless steel
construction, with an easily replaced, inexpensive liner of nylon forming the bearing surface. These bearings will operate satisfactorily with
oU, grease, or water as the lubricant or if necessary without lubrication, with no danger of damage to shaft or bearing. Nylon bearings seem
to be well suited for operation under wet or corrosive conditions such
as are often found in fish cutting plants.
Kniv~
On the sides of the frame p the shafts and bearings for the rotar,y
kni vea are bolted vertically. These consist of two cast aluminum housings
supporting stainless' steel shafts with two ball bearings each. Three
l5-inch-diameter No. 420 stainless steel circular knives are attached
to the top of each shaft with spacers fitted between the blades
to keep them 1/2 inch apart.
The two sets of knives overlap by
:3 1/2 inches as shown in Fig. 5. '1\11 the knives have single bevelled
Fig. 4
- General view of MK III fillet splitting machine.
Fig. 5 -
Plan view of MK III splitting machine.
6
cutting edges and are so arranged that the unbevelled sides ot opposing
blades rub ligh~ly g!vipg a cutting action similar to a pair ot scissors,
thus reducing the tendency of the blades to throw the fillet in the
direction of rotation of the bladeso The blades are lubricated with
water to further reduce this tendency. The lOloler ends of the shafts are
joined by a pair of spur gears to ensure that both blades turn at the
same speed of 220 rpm and in the correot direction relative to each
other. One shaft is extended to accept a l2-inch-diameter V-belt pulley
driven from a I-hp ll50-rpm totally enclosed electric motor mounted vertically on -the side of the maohine.
Finisb
Before assembly all aluminum components were de-greased with
trichlorethylene and given a phosphoric acid etch as recommended by the
Aluminum Company of Canada. This was f.olloved by a thin coat ot zinc
chromate primer sprayed over the metal. The machine was then assembled
and received one coat of aluminum paint and a finish coat of white
enamel.
Tests have shown that approximately 80% of the large fillets split
with this machine would be suitable for sale as fresh or frozen fillets.
The remaining 2~, being for the most part small pieces cut from the top
of the fillet, would be suitable only for use in fish blocks for use in
the manufacture of fish sticks. The assessment is arbi~rar.r and would
depend upon the size of paokage, market, and to some extent on the polia"
of the producar.
Further
informa~ion
JDay be obtained from the authors •
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