Apparatus for filling a film casing with fluid material

A stuffer nozzle of a double pipe type is inserted in a cylindrical member formed by joining opposite ends of a film. Fluid material such as raw egg is supplied from an inner pipe of the stuffer nozzle to fill the cylindrical member with the fluid material. An air valve communicating with an outer pipe of the stuffer nozzle is opened to exhaust air in the cylindrical member and reduce pressure in the cylindrical member in synchronism with a timing that a pair of squeezing rollers squeeze the cylindrical member filled with the fluid material. The squeezed cylindrical member is clamped by a clamping member. The air vent valve is closed to prevent air from entering into the cylindrical member from outside through the outer pipe of the stuffer nozzle in synchronism with a timing that the squeezing rollers are separated from the cylindrical member.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The present invention relates to an apparatus for filling a film casing 
with fluid material such as raw egg separated into white and yolk, and 
more particularly to such a filling apparatus capable of preventing air 
from entering into the film casing. 
2. Prior Art 
Egg used a raw material for sandwiches is separated into white and yolk and 
is filled in a film casing 1 shown in FIG. 8 so that the egg filled in the 
film casing 1 is supplied in a food processing factory. The film casing 1 
is formed into a cylinder by joining the opposite ends of a film made of, 
for example, vinylidene chloride resin at a seal portion of joined portion 
1a. Raw egg is then filled into the cylinder and thereafter both ends of 
the cylinder filled with raw egg are clamped by clamping members 2 such as 
aluminum wires. Raw egg is then heated at it is filled in the film casing 
so that white or yolk of raw egg in the casing is hardened and then 
forwarded to the food processing factory. The film casing is then removed 
from egg in the food processing factory and egg is used as material for 
sandwiches. 
When fluid material such as egg is filled into the film casing 1, there is 
a problem that air enters into the film casing 1 during the filling 
operation. Air entered into the film casing 1 comes to the surface of the 
film casing as an air bubble. Accordingly, when the filled material is 
white or yolk of egg, a portion of the filled egg where the air bubble 
exists is discolored to brown when it is heated. Since the discolored 
portion can be seen through the film casing, the value of the filled egg 
is reduced. Accordingly, when raw egg or the like is filled into the film 
casing, it is necessary to prevent air from entering into the film casing. 
In a conventional filling operation of egg for preventing the entrance of 
air, only one end of a cylinder 40a formed of a film is clamped by a 
clamping member 2 as shown in FIG. 9 and raw egg is filled into the 
cylinder 40a from a filling nozzle. The cylinder 40a filled with egg is 
then set upright in a container 3 shown in FIG. 9 with the other end of 
the cylinder 40a opened and air is exhausted from the cylinder 40a. After 
air has been exhausted from the cylinder, the open end of the cylinder is 
closed tight to prevent the entrance of air and is clamped by a clamping 
member 2 to complete the casing 1. 
However, in the above conventional operation, many processes must be made 
by hand and therefore the operation efficiency is very wrong. 
Accordingly, it is desired to develop an apparatus which automatically 
fills the film casing 1 with fluid material such as egg without entrance 
of air. Heretofore, as an apparatus which automatically fills a 
cylindrical film casing with material, there has been developed an 
automatic filling apparatus which fills a cylindrical film casing with 
processed meat to manufacture sausage as shown in FIG. 10. The automatic 
filling apparatus is continuously fed with film 40 made of vinylidene 
chloride resin to roll it in a cylinder by a forming member 4 and joins 
the opposite ends of the rolled film by high-frequency electrodes 5a and 
5b to form a cylindrical member 40a. Filling material such as processed 
meat is filled into the cylinder member 40a from a stuffer nozzle 6. A 
pair of squeezing rollers 7a and 7b are disposed under the stuffer nozzle 
6 to squeeze ends of the cylindrical member 40a and the squeezed ends are 
clamped by a clamping member 2 formed of for example, aluminum wire. When 
the end of the cylindrical member 40a is squeezed by the rollers 7a and 
7b, the pressure in the cylindrical member 40a is increased. However, the 
increase of the pressure can be adjusted by upward movement of an 
adjustment ring 8 slidably disposed around the stuffer nozzle 6. 
However, since the conventional automatic filling apparatus as shown in 
FIG. 10 is used to fill the cylindrical member 40a with the material such 
as the processed meat which is not fluid and has a tendency that air is 
hard to enter into the cylindrical member together with the material, the 
apparatus is not quite provided with function for exhausting air from the 
cylindrical member 40a. Accordingly, when the apparatus is employed as a 
filling apparatus of fluid material such as egg as it is, much air enters 
into the film casing 1. Further, when the conventional automatic filling 
apparatus is used to fill the film casing with the fluid material, the 
fluid material flows out upwardly from a gap between the adjustment ring 8 
and the inner surface of the film 40. 
SUMMARY OF THE INVENTION 
It is an object of the present invention to provide an apparatus for 
automatically filling a film casing with fluid material such as raw egg 
separated into white and yolk. 
It is another object of the present invention to provide an apparatus for 
filling a film casing with fluid material which can adjust properly 
increase of pressure in the film casing produced when the film casing is 
squeezed by squeezing rollers and can exhaust air in the film casing 
together with the adjustment of the pressure effectively.

DETAILED DESCRIPTION OF THE INVENTION 
A filling apparatus of fluid material shown in figures automatically and 
continuously fills a film casing 1 with fluid material having a certain 
degree of viscosity such as raw egg separated into white and yolk and 
resembling liquid material as compared with processed meat. 
As shown in FIG. 2, stuffer nozzle 10 is formed of a double pipe including 
an inner pipe forming a filling nozzle 11 for feeding fluid material and 
an outer pipe forming an air vent nozzle 12. A top end of the filling 
nozzle 11 is connected to a connection pipe 13 and a top end of the pipe 
13 is connected through a valve 21 to a hopper 22. A supply pipe 23 is 
connected to the hopper 22 and fluid material such as raw egg is fed in 
the hopper 22 from the supply pipe 23. A valve 24 is provided in the way 
of the pipe 23 and is opened and closed in accordance with a quantity of 
the fluid material in the hopper 22 to supplement the fluid material into 
the hopper 22. Further, as shown in FIG. 2, a top end of the air vent 
nozzle 12 forming the outer pipe of the stuffer nozzle 10 is connected 
through an air vent valve 14 to an air vent pipe 25. As shown in FIG. 1, a 
top end of the air vent pipe 25 is opened in an upper portion of the 
hopper 22. 
A forming member 15 is disposed around the upper portion of the stuffer 
nozzle 10. A film 40 made of vinylidene chloride is fed through film 
supply rollers 26 and 27 and is formed into a cylinder by the forming 
member 15. Disposed below the forming member 15 is also a joining device 
16 which is formed of a pair of opposite high-frequency electrodes 16a and 
16b. The opposite ends of the cylindrical film 40 formed by the forming 
member 16 are joined by the high-frequency electrodes 16a and 16b to form 
a cylindrical member 40a made of a film. A lower end of the stuffer nozzle 
10 is inserted in the cylindrical member 40a. 
Upper and lower size rings 17 and 18 are fixedly mounted around the stuffer 
nozzle 10. The outer diameter of the flanges 17a and 17b formed at the 
upper and lower ends of the upper size ring 17 and the outer diameter of 
the lower size ring 18 are formed slightly larger than the inner diameter 
of the cylindrical member 40a of the film formed by forming member 15 and 
the flanges 17a and 17b and the lower size ring 18 are adapted to slidably 
move in the cylindrical member 40a without a gap therebetween. 
Accordingly, when the cylindrical member 40a is filled with the fluid 
material from the stuffer nozzle 10, the outer peripheries of the upper 
and lower size rings 17 and 18 prevent the fluid material from overflowing 
upward. 
An air bubble removing ring 19 is disposed between the upper and lower size 
rings 17 and 18. The air bubble removing ring 19 is provided with a flange 
19a and the diameter of the flange 19a is formed slightly smaller than the 
diameter of the size rings 17 and 18 so that a small gap is formed between 
the outer periphery of the flange 19a and the cylindrical member 40a. As 
shown in FIG. 6, a notch 19b is formed aslant in an outer periphery of the 
flange 19a of the air bubble removing ring 19. As shown in an enlarged 
sectional view of FIG. 7, a narrow outer end piece 40b disposed outside 
the cylindrical member 40a formed by joining the opposite ends of the film 
40 by the joining device 16 and a narrow inner end piece 40c disposed 
inside the cylindrical member 40a are left on both sides of the joined 
portion or seal portion 1a of the cylindrical member 40a. The inner end 
piece 40c is guided in the notch 19b of the ring 19 and the inner end 
piece 40c is forcedly separated from the inner surface of the cylindrical 
member 40a. The filled fluid material is slightly exuded from the lower 
size ring 18 upward, while the exuded fluid material is forced to flow 
between the end piece 40c and the cylindrical member 40a so that air 
bubbles can be prevented from remaining between the end piece 40c and the 
inner surface of the cylindrical member 40a. 
A film advancing roller 31 is disposed below the stuffer nozzle 10 (see 
FIG. 1). The cylindrical member 40a of film is advanced downward by the 
film advancing roller 31 at a constant speed. 
A pair of squeezing rollers 32a and 32b are disposed below the film 
advancing roller 31. The pair of squeezing rollers 32a and 32b are 
opposite to each other so that the cylindrical member 40a formed of the 
film is put between the squeezing rollers 32a and 32b and is squeezed by 
the rollers. The squeezing rollers 32a and 32b are moved between a first 
position in which the rollers are brought into contact with each other to 
squeeze the cylindrical member 40a as shown in FIG. 4 and a second 
position in which the rollers 32a and 32b are apart from each other as 
shown in FIG. 3. One squeezing roller 32a is rotated in synchronism with 
the film advancing roller 31 to advance the squeezed film downward. 
A clamping mechanism is further provided below the pair of squeezing 
rollers 32a and 32b. The film squeezed by the squeezing rollers 32a and 
32b is clamped with clamping members 2 of aluminum wire by the clamping 
mechanism. 
Operation is now described. 
The fluid material such as white or yolk of raw egg is fed into the hopper 
22 from the supply pipe 23 shown in FIG. 1. At this time, the quantity of 
the fluid material in the hopper 22 is adjusted by the opening and closing 
of the valve 24. 
The film 40 of vinylidene chloride resin is continuously fed by the film 
supply rollers 26 and 27 and is formed into a cylinder by the forming 
member 15. The opposite ends of the cylinder are joined to each other by 
the electrodes 16a and 16b of the joining device 16 to form the 
cylindrical member 40a. 
When the valve 21 disposed below the hopper 22 is opened, the fluid 
material in the hopper 22 falls into the inner filling nozzle 11 of the 
stuffer nozzle 10 by the weight of the material. The fluid material is 
filed into the cylindrical film member 40a by the pressure corresponding 
to a head of the fluid material in the hopper 22. During the filling 
operation, the pair of squeezing rollers 32a and 32b are apart from each 
other as shown in FIG. 3 and the cylindrical member 40a is continuously 
advanced downward between the rollers 32a and 32b by the film advancing 
roller 31 at the constant speed. When a predetermined quantity of fluid 
material is filled into the cylindrical member 40a including the lower end 
thereof clamped by the clamping member 2, that is, when the position of 
the clamping member 2 attached to the lower end of the cylindrical member 
40a to prevent the fluid material from flowing out of the cylindrical 
member downward is lowered by a predetermined distance, the pair of 
squeezing rollers 32a and 32b approach to each other to squeeze the 
cylindrical member 40a from both sides thereof. The fluid material in the 
cylindrical member 40a is squeezed by the squeezing rollers 32 a and 32b. 
The fluid material is filled into the cylindrical member 40a being lowered 
is interrupted by the squeezing rollers 32a and 32b and the pressure of 
the fluid material in the cylindrical member 40a is accordingly increased 
rapidly in the state of FIG. 4. 
As shown in FIG. 5, the air vent valve 14 shown in FIG. 2 is opened a short 
time t.sub.1 after completion of the squeezing operation by the pair of 
rollers 32a and 32b and the upper end of the air vent nozzle 12 is opened. 
Thus, the fluid material flows into the air vent nozzle 12 to adjust the 
increased pressure in the cylindrical member 40a by the squeezing 
operation of the rollers 32a and 32b. At this time, air entered into the 
cylindrical member 40a together with the fluid material from the hopper 22 
is exhausted through the air vent nozzles 12 and the air vent valve 14 
from the air vent pipe 25. Since the outer diameter of the lower size ring 
18 is formed slightly larger than the inner diameter of the cylindrical 
film member 40a, the size rings 17 and 18 prevent the fluid material from 
going up between the outside of the stuffer nozzle 10 and the cylindrical 
film member 40a to the position of the high-frequency electrode 16a of the 
joining device 16. 
As shown in the time chart of FIG. 5, after the squeezing operation by the 
squeezing rollers 32a and 32b, the clamping member 2 such a aluminum wire 
is wound on the squeezed film. Consequently, one film casing 1 is formed 
below the squeezing rollers 32a and 32b as shown in FIG. 1. 
After the completion of the clamping operation, the pair of squeezing 
rollers 32a and 32b are separated from each other. As shown in the time 
chart of FIG. 5, the air vent valve 14 is closed a short time t.sub.2 
before the starting time of the separation of the squeezing rollers 32a 
and 32b. When the squeezing rollers 32a and 32b are separated, the 
pressure of the fluid material in the lowering cylindrical member 40a is 
rapidly reduced. However, the air vent valve 14 is closed before the 
separation as described above to prevent air from entering into the 
cylindrical member 40a from the air vent pipe 25 and the air vent nozzle 
12. 
The above operation is repeated so that the film casings 1 of which both 
ends are clamped by the clamping members 2 are continuously manufactured. 
Each of the film casings 1 is separated at the portion where the clamping 
member 2 is clamped as shown in FIG. 8. In the case where the filled fluid 
material is raw egg, it is hardened in a heating process. 
In the filling operation, while the flanges 17a and 17b of the upper size 
ring 17 and the lower size ring 18 prevent the fluid material from going 
up along the outer periphery of the stuffer nozzle 10, the upper surface 
of the fluid material goes up just under the upper size ring 17 and the 
air bubble removing ring 19 is immersed in the fluid material as shown in 
FIG. 4. As shown in FIG. 7, the inner end piece 40c at the joined portion 
1a of the cylindrical film member 40a is guided into the notch 19b formed 
in the flange 19a of the air bubble removing ring 19 and the end piece 40c 
is forcedly separated from the inner surface of the cylindrical member 
40a. Accordingly, the opposite surfaces between the end piece 40c and the 
inner surface of the cylindrical member 40a forming a gap therebetween are 
wetted by the fluid material. Subsequently, the end piece 40c is pressed 
to the inner surfaces of the cylindrical member 40a by the outer periphery 
of the lower size ring 18. However, since the opposite surfaces between 
the end piece 40c and the inner surface of the cylindrical member 40a is 
once wetted by the fluid material, an air bubble is prevented from 
remaining in the gap formed by the opposite surfaces and the air bubble is 
also prevented from gathering under the lower size ring 18. 
The fluid material is not limited to raw egg and the filling apparatus of 
the present invention can attain the same operation and effect as 
described above even if the fluid material is other fluid material which 
has a tendency that air enters into the cylindrical member together with 
the material. 
A time difference in the opening and closing operation between the 
squeezing rollers 32a and 32b and the air vent valve 14 shown by the times 
t.sub.1 and t.sub.2 of FIG. 5 may be set in accordance with various 
conditions such as the viscosity of the fluid material and a sectional 
area of the air vent nozzle 12 forming the outer pipe of the stuffer 
nozzle 10. In certain cases, both or none of the times t.sub.1 and t.sub.2 
may be reduced to zero, or the air vent valve 14 may be opened just before 
the squeezing operation by the rollers 32a and 32b and be closed just 
after separation of the rollers 32a and 32b. 
As described above, according to the present invention, since the stuffer 
nozzle is formed of a double pipe including the inner filling nozzle and 
the other air vent nozzle, air entering into the cylindrical member 
together with the fluid material is exhausted by the other air vent nozzle 
effectively. Further, since the air vent valve coupling to the air vent 
nozzle is opened and closed in synchronism with the operation of the 
squeezing rollers, the increased pressure in the cylindrical film member 
can be adjusted by the squeezing operation of the squeezing rollers and 
air contained in the cylindrical member can be exhausted exactly in the 
squeezing operation. In addition, since air can be prevented from entering 
into the film casing in the case where the fluid material is raw egg, it 
can be prevented that egg hardened by the heating is discolored to brown 
due to