Plug for closing the gullet of a slaughtered animal and device for positioning same

The invention lies in the field of slaughtering animals in a slaughterhouse. One of the operations during the slaughtering process is the removal of the head of the animal, whereby the gullet is severed. The invention has for its object to offer provisions which can ensure an effective and rapid closure of the gullet. For this purpose the invention generally provides a plug for closing the gullet of a slaughtered animal from which the head has been removed, which plug is adapted to be inserted into the gullet and has a larger effective diameter than the gullet for closing.

BACKGROUND OF THE INVENTION 
The invention lies in the field of slaughtering animals in a 
slaughterhouse. One of the operations during the slaughtering process is 
the removal of the head of the animal, whereby the gullet is severed. The 
stomach contents of an animal suspended from the hind legs will hereby 
move downward through the gullet and could there cause bacteriological 
infection of meat parts, work-floor and following locations, such as 
de-boning tables and conveyor belts. 
Hygienic slaughter is mandatory in most countries. The possibilities 
heretofore have however been very limited up to the present. For example 
the gullet can be at least more or less closed off by means of an elastic 
ring. A drawback of this known method is that it is time-consuming and 
does not guarantee a reliable closure of the gullet. 
From CH-A-436 009 a plug is known, which is designed to be introduced into 
the wind pipe of a slaughtered animal. After introducing such prior art 
plug the wind pipe is sufficiently closed to prevent the entrance of 
rinsing water. 
The prior art plug consists of a plurality of parts and has therefore a 
rather complicated structure which makes the plug relatively difficult to 
produce and therefor expensive. 
The invention has for its purpose to provide a plug adapted to ensure an 
effective and rapid closure of the gullet. It is a further purpose of the 
invention to design a plug in a way such that it can be readily 
manufactured at low costs. 
SUMMARY OF THE INVENTION 
For this purpose the invention generally provides a plug as stated in claim 
1. Claims 2-7 give alternatives. 
The use of biodegradable material has the advantage that after the 
slaughtered animal has been processed the plug no longer has to be 
removed. Considered suitable as starch are in principle all normal 
commercial starches, for example grain starches based on maize, wheat, 
rice, barley etc., tuber starches based on potato, tapioca etc., and other 
starches. The starches can have an increased amylose content and/or and 
increased amylopectin content. A starch derivative can be prepared on the 
basis of chemical, physical and/or biotechnological treatments. 
Biodegradable materials, in particular those based on starches or 
derivatives thereof, display a quite strong moisture-absorbing, for 
example hygroscopic character. As a result the plug can be difficult to 
insert into the moist gullet as it adheres rapidly to the inner wall 
thereof. It is therefore advantageous to embody a plug such that the 
moisture-absorbing, for example hygroscopic, properties are limited at 
least on the outer surface, so that in any case insertion can take place 
without difficulty. In this respect a plug of biodegradable material is 
therefore recommended, the outer surface of which is subjected to a 
treatment to reduce the moisture-absorbing, for example hygroscopic, 
properties thereof. 
Such a treatment can be based on arranging a coating layer, consisting for 
example of a powder, an optionally biodegradable lacquer, glycerine or 
other suitable material, or on the action of a gas, such as nitrogen, oil, 
water or another liquid with a suitable temperature. 
Given in claims 9-15 are specifications of devices with which a plug can be 
inserted into the gullet.

In all figures the same components are designated by the same reference 
numerals. 
DESCRIPTION OF THE PREFERRED EMBODIMENTS 
FIG. 1 shows a device 1 which is intended for inserting a cone-shaped plug 
3 into a gullet 2 for closing thereof. The plug 3 displays a generally 
conical shape with a rounded top 4, a conical body 5 and a broad bottom 
edge 6 with protrusions 7. From a magazine (not drawn) successive 
cone-shaped plugs 3 are supplied via a feed conduit 8 and carried into a 
tube 9 on the underside of which is movable a drive rod 10 driven by a 
pneumatic tool (not drawn). 
As FIG. 2 shows, the drive rod 10 can transport upward a plug 3 carried to 
the open end of tube 9. 
The free end of tube 9 bears four resilient segments 11, which carry hooks 
12 on their ends. Due to the tapering form of segments 11 a passing plug 3 
presses these segments outward, whereby the segments 11 inserted into the 
gullet 2 come with hooks 12 into engagement with the inner surface of 
gullet 2, whereby a relative displacement of device 1 and gullet 2 is 
effectively blocked from that moment. This is a requirement in order to 
ensure that drive rod 10 can position the plug 3 in the gullet with some 
force. In order to obtain the desired closing properties the bottom edge 6 
namely has a larger diameter than gullet 2, which can therefore only 
receive plug 3 by stretching. FIG. 2 shows the situation in which plug 3 
is about to leave the segments 11 and can be transported further by drive 
rod 10. 
It will be apparent that after passing the end of segments 11 the plug 3 is 
only supported by rod 10, and the hooks 12, which are designated with 12' 
in FIG. 2 in their expanded position, spring back to the position shown in 
FIG. 1, with the understanding that, due to the shape and the outwardly 
directed force, hooks 12 remain in hooking coaction with gullet 2. The 
cone-shaped plug 3 can thereby be displaced further by the drive rod 10. 
If it is then desired to remove device 1 with segments 11 and hooks 12 from 
the gullet, this can then be done for example by performing a small inward 
directed movement followed by a rearward withdrawal, or by retracting it 
with force, wherein some damage to the gullet can occur. 
FIG. 3 shows a device 13 which comprises a pistol-grip 14 with trigger 15 
with which the pneumatic tool can be controlled which drives the drive rod 
16. 
FIGS. 4a and 4b show the plug 3 in cross-section and top view respectively. 
FIGS. 5a and 5b show an alternative embodiment of plug 3. This generally 
cone-shaped plug 17 has a bottom edge different from the plug 3. The 
protrusions are embodied here as six quite sharp radial ribs 18, while 
protrusions 7 of plug 3 are somewhat more gently tapering serrations of 
the bottom edge 6. 
In cases where the hooks 12 are not sufficiently capable of fixing the 
gullet relative to the insertion tool, in an alternative the gullet can 
for example be fixed relative to the insertion tool by means of clamps or 
a clamping ring. A clamping ring can extend for instance round the gullet 
and secure the gullet wall against the segments situated on the inside. 
The insertion tool can also be embodied such that simultaneously with the 
insertion of the plug the gullet is separated from the windpipe. 
The plugs can be embodied in plastic of a re-usable type. Use can also be 
made of biodegradable materials. Starch can also be employed whereby an 
inserted plug will gradually dissolve. 
FIG. 6 shows a plug 19, which has the general shape of a beaker tapering 
toward the bottom 20. The bottom 20 has a recessed portion 21, the 
function of which will be explained hereinafter. Beaker 19 comprises a 
rotation symmetrical beaker wall 22 consisting of two truncated conical 
parts 23 respectively 24 mutually connecting in stepped manner. 
FIG. 7 shows an insertion tool 25. This insertion tool 25 comprises a 
substantially rigid tube 27 connected via a conduit 26 to a source of 
underpressure. The connection between the flexible conduit 26 and the tube 
27 can be effected by means of a hand-operated button 28. By manually 
pressing button 28 the tube 27 is connected to the source and by releasing 
button 28 the connection is again broken. 
The outer diameter of tube 27, at least on its free end 29, is a little 
smaller than the inner diameter of the recess 21 of plug 19 (see FIG. 6). 
By placing the end 29 in the vicinity of the interior of recess 21 and by 
pressing in button 28 a plug 19 can thus be sucked thereon. The plug 19 
can herewith then be inserted into gullet 2 in the manner shown in FIG. 
8a. It will be apparent that during this insertion the said suction is no 
longer necessary. The plug 19 can thus be pressed into a desired position 
in the gullet by exerting a pushing force. The thereby exerted force is 
however still not sufficient for reliable and hygienic closure of the 
gullet. 
As shown in FIG. 8b, tube 27 is subsequently shifted back over a short 
distance and the button 28 is operated such that an underpressure is 
created in the interior of plug 19 as a result of which the flexible wall 
of the gullet is drawn inward into the interior of the beaker-shaped plug 
19. FIG. 8b shows this situation. 
FIG. 8c shows the situation in which tube 27 is then slid out while the 
underpressure is maintained. The flexible wall of gullet 2 forms in the 
manner shown in FIG. 8c an effective closing of the interior of plug 19. A 
very effective and reliable closure of the gullet is realized due to the 
shown form. 
FIG. 9 shows the manner in which the gullet 2 can be separated from the 
surrounding tissue, for example its connection to the windpipe 30. The 
connection between gullet 2 and windpipe 30 is relatively weak and can 
therefore be broken in simple manner. As shown in FIG. 7, the device 25 
carries for this purpose on its handle 31 a carrier rod 32 which extends 
parallel to tube 27 and which in this embodiment forms a continuation of 
the cylindrical handle 31. The free end of this carrier rod 32 bears a 
separating element 33 which in the manner indicated by the arrow 34, after 
rotation of handle 31 and therewith the separating element 33, can effect 
the intended separation during axial movement thereof. 
At the moment the situation shown in FIG. 8b is reached the tube 27 can be 
retracted by the user. The said rotation, for example through 
approximately a quarter turn, can take place prior thereto whereby the 
separating element 33 penetrates into the tissue connecting gullet 2 to 
windpipe 30. During the downward directed movement 35 of handle 31 and 
therewith of separating element 33 the connection is broken. 
FIG. 10 shows a cross-section of a preferred embodiment. The plug 36 has a 
generally rotation symmetrical form of a beaker, the bottom zone 37 of 
which has a comparatively small diameter wherein the operational end of 
the suction tube 27 fits. A broadened part 38 connects thereto via a 
smooth transitional zone 39. To the broadened part 38 connects a further 
broadened part 40 which has on its underside a thickened peripheral edge 
41 to strengthen the plug 36. The transition of the inner surfaces of the 
parts 38 and 40 takes place via a step 42. On their outer surfaces these 
parts interconnect smoothly via a transitional zone 43. 
It is noted that the tube 27 can have an enlarged breadth and narrowed 
active end. If desired the active end can be provided with one or more 
openings present on the outer surface, which simplifies the creation of 
the desired underpressure in a plug.