Sausage diameter monitoring apparatus and method

A method and apparatus are disclosed for monitoring the diameter of sausages and providing a visual display of the diameters. A sausage contact means is mounted along a conveyor which carries the sausages from the stuffing apparatus. The sausage contact means monitors the diameter of the sausages moving along the conveyor, and any difference between these diameters and a selected standard diameter is displayed on a statistical analyzer visible to the operator of the stuffing apparatus.

This present invention generally relates to sausage-making methods and 
apparatus. More particularly, the present invention relates to a method 
and apparatus for monitoring the diameter of stuffed sausages and 
providing a visual display of these diameters. 
The techniques and apparatus employed for stuffing large sausages are well 
known in the meat industry. Typically, the open end of a casing is fitted 
over a stuffing horn, and the sausage mixture of comminuted or chopped 
meat, together with selected spices and flavorings, is forced through the 
stuffing horn into the casing. The discharge of the mixture into the 
casing fills that portion which is directly in front of the stuffing horn 
and simultaneously acts to move the casing from the stuffing horn. 
Frictional retention of the casing on the stuffing horn (as by clamps, 
hand pressure, internal gripping fingers, etc.) controls the stuffing 
pressure and the amount of sausage mixture in the stuffed casing and, 
accordingly, the diameter of the stuffed casing. 
In many instances, the diameter of the sausage is not critical, and any 
sausage is acceptable if the sausage diameter falls within a relatively 
wide tolerance. However, in certain instances (such as packaging in 
close-fitting cavities in preformed, rigid plastic containers) the sausage 
diameter must be held within relatively close tolerances for the slices to 
fit within the cavities. 
In the past, mechanical devices analoguous to the linkage of a weighing 
scale have occasionally been used to monitor the diameter of sausages 
during stuffing. However, such devices have been of limited success for 
various reasons. 
Accordingly, an object of the present invention is to provide an improved 
method and apparatus for monitoring the diameter of sausages. 
Another object of this invention is to provide a method and apparatus for 
monitoring the diameter of sausages during stuffing so that adjustments 
may be made to correct for diameter variations (based on a standerd 
diameter). 
A further object of the present invention is to provide a method and 
apparatus for recording the differences in the sausage diameters from a 
selected standard diameter to provide a record from which certain sausages 
may be selected for various uses. 
These and other objects of this invention will be apparent from the 
following description and drawings. 
In this application, the term "monitoring" refers to measuring or gauging. 
The present invention provides a precisely adjustable sausage contact means 
which monitors the diameter of each sausage as the sausage moves along a 
conveyor carrying the sausage away from the stuffing apparatus. The 
sausage contact means is operatively connected to a statistical analyzer 
which provides a visual numerical display of the amount by which the 
diameter of the sausage differs from the preferred diameter. The display 
is mounted so as to be visible to the operator of the stuffing apparatus, 
so that immediate corrective measures can be taken to reduce the number of 
sausages which are out of tolerance. To further alert the operator of the 
sausage stuffing equipment that sausages are being stuffed out of the 
preferred diameter range, an alarm condition (such as a light or buzzer) 
may be used to signal the operator to make an immediate adjustment at the 
stuffing horn. 
A printer may be used with the statistical analyzer to record the sausage 
diameters to provide a production record. In the preferred embodiment, 
this is accomplished by providing a switch downstream of the sausage 
contact means. When the end of a sausage engages the switch, the 
statistical analyzer is triggered to print the diameter reading which is 
being displayed at that time. 
In the illustrated embodiment which will be discussed later, the distance 
between the switch and the sausage contact means is about one-half the 
length of a sausage. Thus, the printer records any difference in diameter 
at approximately the middle of the sausage. Also, this diameter may be 
printed for only selected sausages, e.g., every third, fourth or fifth 
sausage. From this production record, those sausages falling within the 
acceptable range of diameters can be selected for various uses. 
Accordingly, production delays and waste associated with excessive 
production of out-of-tolerance sausages can be minimized.

In summary, referring to FIG. 1 the present invention is generally employed 
in combination with a sausage stuffing appatatus 10 which forces a chopped 
or comminuted meat mixture into a casing 12 to form an elongated sausage 
14 of substantially uniform cross-sectional shape and size. After the 
casing has been filled, the sausage is conducted, via horizontal conveyor 
16, away from the sausage stuffing apparatus 10. In the illustrated 
embodiment, the sausage is eventually discharged onto a vertical conveyor 
18 which carries the sausage to the next operation, such as cooking. 
In accordance with the present invention, sausage contact means, generally 
at 20, is mounted at a position along the horizontal conveyor 16, so as to 
contact the surface of the sausage as the sausage is moved along by the 
conveyor, permitting the sausage diameter to be monitored. The sausage 
contact means is operatively connected to a statistical analyzer 22 which 
provides a visual numerical readout 24 of the amount by which the sausage 
diameters differ from a selected standard diameter. The analyzer further 
includes a printer 26 for recording the sausage diameters at a 
predetermined location. 
In the present invention, the distance between the sausage contact means 20 
and printer energizing switch 28 is approximately one-half the length of 
the sausage, so that the recorded diameter is approximately at the sausage 
mid-point. 
Turning now to a more detailed description of the present invention, the 
sausage stuffing apparatus 10 is of the type generally well known in the 
industry. To make a sausage, the operator places the casing 12 over the 
stuffing horn (not shown). The meat mixture which comprises the sausage 
contents is forced through an in-feed pipe 32, through the stuffing horn 
and into the casing. As the mixture flows into the casing, the casing is 
moved away from the horn, As noted earlier, the force required to move the 
casing from the stuffing horn is determined by the friction between the 
casing and the stuffing horn. These sausage stuffing techniques are well 
known in the meat packing industry. 
After the stuffing of the sausage is complete, the open end of the casing 
is closed, and the sausage proceeds along a conveyor 16a leading away from 
the stuffing apparatus. Downstream of the stuffing apparatus, air cylinder 
34 is provided to push the sausage onto an adjacent parallel conveyor 16b. 
The parallel conveyor conducts the sausage through a water spray 36 which 
cleans the outside of the casing and then downstream to an off-loading 
position where the sausage is discharged onto vertical conveyor 18. 
For contacting and monitoring the diameter as the sausage moves along the 
conveyor 16b, the sausage contact means 20 is mounted at a fixed position 
downstream of the water rinse 36. The sausage contact means (referring to 
FIG. 2) is mounted above the horizontal conveyor 16b by a support bracket 
38. The sausage contact means 20 has a fixed element 40 attached to the 
support bracket 38 and an adjustable element 42 which is slidably mounted 
with respect to the fixed element 40, for adjustment toward or away from 
the conveyor. Both elements are preferably made of rigid plastic material 
which is compatible with food processing, although other materials also 
may be suitable. 
FIG. 5, the fixed and adjustable elements are held together by 
spring-tensioned bolts 44 which extend through access slots 46 in the 
fixed element and threadedly engage the adjustable element 42. A 
compressed coil spring 48 extending between washer 50 and the head of each 
bolt 44, biases the bolts to hold the adjustable element 42 in close 
contact with the fixed element 40 while permitting vertical adjustment of 
element 42 within access slots 46. 
To assure proper alignment the two elements 40 and 42, the adjustable 
element 42 has a raised vertical rib 52 on the inside surface which is 
slidably received in a matching shallow groove 54 on the inside surface of 
the fixed element 40. For adjusting the relative vertical position of the 
movable element 42, the movable element has a threaded follower 56 
attached to the raised rib 52. The follower extends into a center slot 58 
in the fixed element 40, through which a lead screw 60 extends. The lead 
screw is held in a fixed axial position in the stationary element 40 by a 
set screw 62 which extends into an annular groove 64 on the lead screw. 
Thus, rotation of the threaded lead screw precisely moves the follower 56 
and the adjustable element 42 up or down relative to the fixed element 40. 
For actually contacting the surface of a sausage (referring to FIGS. 3 and 
4), a circular contact member 66 is mounted at the lower end of a push rod 
68 which extends vertically through the adjustable element 42. The upper 
end of the push rod terminates immediately below a contact arm 70 of 
electronic gauge head 72. The circular contact member directly contacts 
the surface of the sausage, so that changes in diameter result in 
corresponding movement of the push rod which is sensed by the gauge head. 
As best seen in FIGS. 4 and 5, with cover plate 73 removed, an oval center 
portion of the adjustable element 42 is hollowed out to permit assembly of 
the push rod as shown. The push rod is downwardly biased by a compressed 
coil spring 74 extending between the inside surface 76 of the hollowed-out 
area and sleeve 78 axially fixed on the push rod. Push rod sleeves 80 and 
82 spaced on either side of the lower edge of the adjustable element 42 
limit the upward and downward movement of the push rod to a distance D, 
which must be greater than the difference between the minimum and maximum 
preferred sausage diameters. The spring 74 biases the push rod to the 
bottom position, so that when no sausage is present, the display 24 on the 
statistical analyzer 22 is similar to that for a sausage which has a 
diameter smaller than the preferred range. 
At one end of the push rod 68, the contact member 66 which contacts the 
sausage is a generally circular rigid plastic disc with curved lower edges 
to prevent snagging on the casing and to slide easily over the rounded 
butt ends of the sausages. At the other end of the push rod, the gauge 
head 72 is provided to detect minute movement of the push rod resulting 
from a change in sausage diameter. The gauge head may be of various 
commercially available devices which are designed to detect very small 
dimensional differences from a selected standard. One type of gauge head 
which is suitable for the present invention in Model No. EHE-1056 marketed 
by Federal Products Corporation of Chicago, Ill. 
The preferred gauge head 72 is mounted on the side of movable element 42 by 
bolted attachment to bracket 75 and generates an electric signal 
responsive to very small changes in the push rod position, i.e., by 
changes in the sausage diameter, which is fed by electric lead 84 to the 
statistical analyzer 22. The statistical analyzer 22 is preferably also of 
a type which is commercially available, such as Model No. 711 from Federal 
Products Corporation of Chicago, Ill. The analyzer is preferably turned 
90.degree. from the position shown in FIG. 1, so that the analyzer faces 
the operator of the stuffing apparatus 10. On the face of the analyzer is 
the lighted numerical display 24 which provides the operator with a visual 
indication of the difference between the selected standard diameter and 
the sausage diameter being monitored at that instant. This display may be 
continuous, and may even vary throughout the length of a single sausage, 
if the diameter is not uniform. 
An alarm condition may be provided in the form of a light 86 on the 
analyzer panel or a buzzer (not shown) to indicate that the sausage being 
monitored at that instant is out of tolerance, thereby signalling the 
operator to take corrective action. 
In FIG. 6, to provide a production record, the analyzer 22 is used with a 
printer 26 for recording the diameter of sausages being stuffed. In 
accordance with the preferred embodiment, only the diameter in the middle 
of every fifth sausage is actually recorded. Of course, this may be varied 
to record the diameter more or less often than every fifth sausage, or at 
more than one location on each sausage, without departing from the present 
invention. 
In the present invention, the printer is energized by switch 28 to print 
the difference in diameter being monitored at the particular instant when 
switch 28 closes. As described briefly above, switch 28 is located 
adjacent to the conveyor 16b so as to engage the end of a sausage 
approximately when the middle of the sausage is passing beneath the 
sausage contact means 20. Accordingly, the recorded difference from the 
standard, if any, is for the midpoint on the sausage, which is believed to 
be a fair representation of the diameter throughout the sausage. As with 
the alarm condition, the printer 26 also operates to specially identify on 
the printed tape, as by an asterisk, those sausages having diameters not 
falling within the preferred diameter range. 
Although decribed in terms of a preferred embodiment, this invention can be 
embodied in various forms and, therefore, is to be construed and limited 
only by the scope of the appended claims.