Product code wheel assembly

A code wheel for imprinting legends on packages traveling along a conveyor line has a U-shaped slot therein through which the code wheel is coaxially positioned on a drive sleeve rotatable with the line and drive pins engage the sleeve to index the code wheel thereon as resiliently held thereagainst by a releasable collar. Print type carried on the outer surface of the code wheel are independently secured by individual spring detents. A roller having an outer resilient cover is pivotally supported on the conveyor line and spring biased toward the code wheel for establishing the printing pressure on the packages.

BACKGROUND OF THE INVENTION 
The present invention relates to coding devices and, in particular, a code 
wheel for imprinting product code information on containers traveling 
along a packaging conveyor line. 
The present invention finds utility with respect to cartons, packages and 
like containers which must bear legendary information with respect to the 
manufacturing process. This is particularly true for the food processing 
industry and the present invention will be described with specific 
reference thereto although it will be appreciated that the product coder 
is widely applicable to situations where the coded information is required 
for each item being packaged. By coding certain categories of 
manufacturing and product information on the container, each item becomes 
a referenced and traceable product. For instance, the code may contain 
data regarding the date and time of manufacture, the product location 
thereof, as well as product content information. In the event of problems 
associated with the product, the code will assist in identifying the 
underlying causes by enabling cross-reference to the process parameters at 
the time and location of manufacture. Should a recall of products be 
required, the consumer or merchant will be able to quickly determine 
whether their goods are involved by examining the product code imprinted 
on the container. The more information the code contains, the easier it 
becomes to obtain accurate referencing of the product and its manufacture. 
Generally, the product code is printed on the carton contemporaneously with 
the final packaging of the product. As the filled carton moves along the 
packaging conveyor line, a suitable portion of the carton, such as the end 
flap, passes under a rotating code wheel. The code wheel contains a 
circumferential series of type having raised characters corresponding to 
the code. As the flap of the carton passes between the code wheel and a 
back-up roller, the product code is impressed or debossed on the flap. It 
is of prime importance that the product code be regularly updated with 
manufacturing time designations. While in some instances a date may be 
sufficient, generally it is preferred to update the product code on an 
hourly basis. For each such update in the product code, the production 
line must be stopped and the code wheel removed or replaced with a code 
wheel bearing the current information. During this changeover, the entire 
production line is stopped thereby halting both upstream processing and 
downstream packaging operations. As production rates oftentimes exceed 200 
units per minute, the changeover can result in significant lost 
production. Inasmuch as these code wheels must provide uniform debossing 
and printing location on the flap, the wheels must be mounted for 
synchronized rotation with the conveyor line. Generally, this is provided 
by a line driven rotating shaft on which the code wheel is rotatably 
supported. The code wheel is coupled to the shaft by suitable fasteners, 
such as set-screws or the like, and indexed thereon by keys or flats. The 
removal and replacment of the code wheels requires operator access to such 
fasteners. When the line is stopped however, the fastener may not be 
accessible thereby requiring momentary starting and stopping of the line 
until the fastener access is obtained. This increases the changeover time 
and requires high level operator dexterity. The dexterity and orientation 
requirements result in substantial time being required for the changeover 
of such devices. The debossing pressure for the product code is provided 
by hardened back-up wheel which is spring biased against the outer surface 
of the code wheel with the carton flap passing therebetween. At the high 
production speeds, the impacting of the code wheel type against the 
back-up wheel causes a peening of the type characters. Over a period of 
time, the type clarity is lost and the type must be replaced. However, the 
new type also presents problems. If significantly higher than the 
remaining characters, the new character may penetrate the flap and result 
in a loss of carton integrity after sealing. At the aforementioned high 
rates of production, the type must be securely retained against 
centrifugal force while being removable for product code changes. This is 
typically been provided by the use of a elastomeric o-ring, which is 
retained in a circumferential groove and engages a groove on the side face 
of the type. However, the o-ring is subject to wear, particularly at the 
location of highest change frequency. Due to excessive wear, the type is 
prone to ejection from the code wheel with the consequent loss of 
production time and loss of improperly coded product. 
BRIEF SUMMARY OF THE INVENTION 
The present invention overcomes the above-mentioned problems associated 
with prior art code wheels by providing a product coder for imprinting 
codes on cartons which are removed and installed by easily executed, 
self-aligning movement regardless of wheel orientation and which securely 
holds readily removable print and prints with greater clarity over 
lengthened periods of time. These features are achieved by a cylindrical 
code wheel which has a U-shaped axially extending and radially opening 
slot. The slot has a cylindrical base surface which engages a sleeve 
secured to the conveyor line indexing shaft. When the code wheel is 
inserted through the slot onto the sleeve, it is coaxially aligned with 
the shaft. The code wheel further includes axially projecting drive pins 
which are disposed on one axial end face. The drive pins register with 
complementary formed holes on a flange of the sleeve. By rotating the 
wheel about the base to the indexed position and thereafter axially 
shifting the wheel into abutment with the sleeve, the code wheel is 
circumferentially and axially located in the proper position. These 
positional movements can be accomplished independent of shaft orientation 
and without requiring operator line of sight access. The code wheel is 
retained in the indexed position by means of a spring biased collar which 
is compressed to permit insertion and release of the code wheel and which 
upon release resiliently biases the code wheel against the flange to lock 
the code wheel to the sleeve. 
The code wheel further includes a plurality of radial slots of rectangular 
cross-section. Type having the appropriate code characters are slidably 
received in the slots. Individual spring biased detents carried on the 
code wheel engage detent grooves in the type to securely hold the type in 
place while readily accommodating removal and insertion thereof. The 
detents are also effective to compensate for type wear without loss of 
retention force. The aforementioned peening of the type face is overcome 
by a spring biased resilient roller. The roller establishes a uniform but 
yielding pressure at the type face notwithstanding differential character 
type heights. The code wheel assembly as above described may be removed 
and replaced with a code wheel of a current code with great rapidity in 
comparison with the prior devices requiring set screws and like fasteners 
typically in less than one-half minute. This contrasts with about one to 
two minutes required for skilled operators to replace prior coding 
devices. At the packaging rates as described above, the time saving 
substantially increases production rate and the printing uniformity 
reduces the number of improperly coded containers.

DETAILED DESCRIPTION OF THE INVENTION 
Referring now to the drawings wherein the showings are for the purposes of 
illustrating the preferred embodiment of the invention only and not for 
purposes of limiting same, FIGS. 1 and 2 show a product conveyor line A 
having a conveyor belt 10 for moving product cartons 12 along a horizontal 
conveyor path 14. The conveyor line A including the belt 10 and associated 
conveyor frame 16, partially illustrated, may be of any commercially 
available type and does not constitute a part of the present invention. 
Conventionally operatively associated with the conveyor system A, is a 
transversely projecting shaft 18 which is rotated in synchronization with 
the movement of the conveyor belt 10 by a drive mechanism, not shown. A 
product code assembly 20, as hereinafter described in detail, debosses or 
imprints a product code on an end flap 22 of the carton 12 as the carton 
12 moves past a product coding station. 
The product code assembly 20 comprises a code wheel assembly 30 rotatably 
mounted on the shaft 18 and a back-up wheel assembly 32 mounted on the 
conveyor frame 16. The back-up wheel assembly 32 is located adjacent to 
the side of the conveyor belt 10 such that a back-up roller 34 thereon 
supports the lower surface of an end flap 22 in a substantially horizontal 
printing position. The shaft 18 and the code wheel assembly 30 are 
transversely located with respect to the conveyor path 16 and sized and 
located thereabove such that a type array 36 carried by the code wheel 
assembly 30 engages the upper surface of the end flap 22 with sufficient 
printing pressure to deboss a product code legend thereon. The product 
coding station may be located at various locations along the conveyor 
line, but preferably at a point after the carton 14 has been filled with 
product and before the final sealing of the carton 14. The product code 
imprinted by the type array 36 will thus constitute a product code 
containing data referencing the manufacture of the completed product. 
The back-up wheel assembly 32 comprises the roller 34 which is rotatably 
mounted on a pivoting bracket 37 by means of a bearing assembly 38. One 
end of the bracket 37 is pivotally connected to the frame 16 by a pin 40 
which is welded to the frame 16. The outer end of the bracket 37 is 
horizontally supported by a compression spring 42 which is carried by the 
base leg 44 of an L-shaped mounting bracket 46 which is secured to the 
frame 16 by means of a spacer plate 48 and fasteners 50. The upper end of 
the spring 42 is retained within a downwardly opening counterbore on the 
lower surface of the bracket 36. A nut and bolt assembly 52 extends 
axially through the spring and vertically aligned holes in the brackets 36 
and 46 by adjustment of the length of the assembly 52, the printing 
pressure of the wheel 34 against the type array 36 can be controlled. The 
spring 42 also permits resilient deflection of the back-up roller 34 and 
bracket 36 about the pin 40 to maintain continuous contact between the 
code wheel assembly 30, including the type array 36. 
The code wheel assembly 30 comprises a two-piece product code wheel 60 
drivingly connected to a drive hub 62 carried by the shaft 18 and 
releasably held thereagainst by a spring collar assembly 64. 
Referring to FIGS. 3 and 4, the drive hub 62 comprises a cylindrical sleeve 
66 having an annular axial flange 68 welded at one end thereof. As shown 
in FIG. 2, the shaft 18 and the sleeve 66 are provided with oppositely 
facing axially extending keyways which retain a square key, as shown in 
FIGS. 2 and 5 for locking the drive hub 62 to the shaft 18. The drive hub 
62 may additionally be provided with suitable fasteners such as set screws 
for further increasing the coupling with the shaft 18. 
The spring collar assembly 64 is retained at an inboard end of the sleeve 
66 and comprises a release collar 72, a stop ring 74 and a compression 
spring 76. The stop ring 74, as shown in FIG. 2, is a split circular ring 
having the individual halves threadably connected by means of set screws 
77 for clamping the stop ring 74 to the sleeve 66. 
Referring to FIGS. 3 and 4, the release collar 72 is generally cylindrical 
and has a radially inwardly turned annular flange 78 which is slidably 
received over the outer surface of the sleeve 66. A radially outward 
annular flange 82 is formed at the other end of the collar 72 and may be 
suitably knurled to facilitate manual gripping thereof. The compression 
spring 76 is received over the outer surface of the sleeve 66 and has one 
end which engages the inner surface of the flange 78 of the release collar 
72 and the other end which engages the stop ring 74. The collar 72 may be 
manually axially shifted against the biasing of the spring 76 to shift the 
collar 72 between the released position shown in FIG. 3 and the retracted 
position shown in FIG. 4. The position of the stop ring 74 may be axially 
adjusted on the sleeve 66 to vary the compression of the spring 76 but to 
still provide for the insertion and removal of the code wheel 60 as 
hereinafter described. 
Referring to FIGS. 3 through 5, the code wheel 60 comprises a cap 90 and a 
type holder 92 which are aligned by two drive pins 94 and clamped together 
by two set screws 96. The code wheel 60 is cylindrical and has a U-shaped 
axial slot 100 formed therein as more clearly shown in FIG. 5. The slot 
100 is defined by semi-circular base 102 and parallel side walls 104, 
extending from the base to the periphery of the code wheel 60. The base of 
the code wheel 60 has a close sliding fit with the outer surface of the 
sleeve 66 to coaxially align the code wheel thereon. The width of the 
radial opening defined by the slot 100 is slightly greater than the 
diameter of the sleeve. The U-shaped slot in the cap 90 may be the same 
as, but is preferably slightly wider than the slot in the type holder 92. 
By virtue of the dimensions of the slot 100, the code wheel 60 may be 
positioned on the shaft 18 by radial insertion until the outer surface of 
the sleeve 66 engages the base 102 of the slot 100. At this point, the 
code wheel 60 will be coaxially aligned with the shaft 18. As the code 
wheel 60 is axially translated along the sleeve 60 or rotated thereabout, 
the coaxial alignment is maintained. 
The drive pins 94 are press fitted through holes 95 in the type holder 92 
with free ends axially projecting outwardly on either side thereof. One 
free end is slidably received within a through hole in the cap. The other 
free end is slidably received within a through hole in the flange 62. The 
sliding fits of the drive pins circumferentially and radially orient the 
cap 90 with the type holder 92 and circumferentially indexes the code 
wheel 60 with respect to the shaft 18. It also provides the driving 
connection between the rotating shaft 18 and the code wheel 60 through the 
drive hub 30. 
For assembly, the collar 72 is retracted as shown in FIG. 4, and the code 
wheel 60 is axially inserted onto the shaft 18 until the base 102 of the 
slot 100 engages the outer surface of the sleeve 66 thereby providing the 
radial alignment. While maintaining the drive alignment, the code wheel 60 
is rotated until the drive pins 94 are aligned with the holes in the 
flange 68. The code wheel 60 is then axially shifted toward the flange 68 
until the facing surfaces of the type holder 92 and the flange 68 abut. 
The spring collar 72 is released and the spring 76 compressively biases 
the code wheel 60 against the flange 68 to maintain the indexed 
relationship with the shaft 18. For removal of the code wheel 60, the 
aforementioned procedures are reversed. As shown in FIG. 4. the collar 72 
is retracted and the code wheel 60 axially shifted until the pins 94 exit 
the flange holes. The code wheel 60 is rotated about the base 102 until 
the slot is aligned with the permissible withdrawal path and radially 
withdrawn from the shaft without interference from surrounding conveyor 
structure. The aforementioned insertion and removal may be provided by 
operator feel alone in view of the self guided alignment surfaces provided 
by the assembly. 
The type array 36 is comprised of a circumferential series of individual 
type 110 retained in radial slots 112 formed in the type head 92. 
Referring particularly to FIGS. 5 through 7, the type 110 have rectangular 
cross-sections and are formed with alpha-numerical raised characters 114 
on the outer face thereof. Transverse recesses 116 are formed in opposed 
lateral faces thereof. The type may include a single character or may 
comprise a series of characters. The single character type are preferably 
rectangular solids while the multi-character type may be sector shaped 
with radially converging side walls. The type head 92 has a 
circumferential channel 120 formed in the axial face abutting the cap 90. 
The inner diameter of the channel forms the abuttment surface for the type 
110 and has a diameter in relation to the height of the type that 
establishes a predetermined projection of the type beyond the outer 
circumferential surface of the code wheel. A plurality of constant width 
radial slots are formed outwardly of the channel and in assembly provide 
for a sliding fit of the single character type into seated relationship. 
The sector type may have parallel side walls or depending on the extent of 
the sector, may have inwardly converging walls with the slots being 
similarly formed. A plurality of threaded holes 122 are formed in the head 
92 and the cap 90 and alternatingly register with the type slots 110. 
Threaded fasteners 124, having captive spring-biased tips 126 are 
threadably inserted in the holes 122 with the tips compressively engaging 
the surface of the recesses 116 to thereby releasably retain the type 110. 
Two such fasteners may be provided for the sector type. By alternating the 
location of the holes 122 between the cap 90 and the head 92, even narrow 
width type can be individually retained. The type may be removed and 
installed by using a suitable tool such as pliers to grasp projecting 
portions of the type and sliding that type past the detenting of the 
fasteners 124. 
Referring specifically to FIG. 7, the type array 36, for illustration 
purposes, comprises a series of seven individual character type and one 
sector multi-character type. The type characters are mirror images such 
that the debossing on the carton flap will bear conventional orientation. 
Depending on the rotation of the code wheel, the circumferential series 
will be appropriately arranged. For illustration purposes, the code array 
reads as "1 3 1 4 7 H 1 P695." The debossment of this character array 
establishes the product code or legend designating certain aspects 
relative to the manufacturing operation and the product. Rather than 
straight numerical, alphabetical characters may be used as required to 
increase the information content for a given number of type characters. 
For instance, the first number may designate plant site and the second 
number the production line at that site. The third through fifth 
characters may designate the day of manufacture, the sixth character an 
alphabetical designation for hour of manufacture and the seventh character 
a designation of the year of manufacture. The sector legend may contain 
code information relative to the product itself or other manufacturer 
information which is separate from the product code itself. 
Referring to FIGS. 1-2, in operation, the shaft 18 will rotate in 
synchronization with the speed of the conveyor belt 10. The outer diameter 
at the type 110 is selected to match the peripheral speed of the belt 10 
such that the carton flap 22 will be imprinted by the type array 36 with a 
rolling, non-slipping, printing action. More particularly, the carton 12 
will be shuttled along the conveyor belt and spaced from adjacent 
containers by means of projecting lugs or the like, not shown. The lugs 
will be synchronized with respect to the rotation of the shaft such that 
the printing on the flap 22 will commence in a select longitudinal area 
thereof. As the carton approaches the printing station, the lead edge of 
the flap will roll over the outer surface of the back-up wheel 34. 
Preferably the back-up wheel will be spaced from the outer surface of the 
head by means of the fastener assembly 52. As the lead character of the 
type array engages the top surface of the flap 22, the back-up roller 34 
will establish sufficient pressure to emboss the character in the surface 
thereof. The other characters will be sequentially debossed thereon. The 
debossing will sequentially take place as each container flap is presented 
at the coding station. The resilient material in the back-up roller 
provides a resilient printing surface for the type characters and 
accommodates variations in the projecting type height. Accordingly, the 
uniform pressure will be exerted at the printing interface notwithstanding 
the height variations as may be caused by the difference in the wear rate 
of the individual characters. This also avoids any peening action which is 
likely to occur without a deflectable and resilient roller. 
At time of code revision, which typically will take place on an hourly 
basis, the conveyor line A is stopped. The code wheel 60 may come to rest 
at any random circumferential orientation. Inasmuch as no fasteners are 
involved in the subject assembly, the rest position is not critical to the 
removal and replacement of the code wheel 60. For removal as described 
above, the operator merely retracts the collar 72, grasps the cap and 
axially slides the code wheel 60 from engagement with the flange 66. This 
releases the drive pins from the holes and permits the code wheel to be 
rotated about the sleeve 66 until the slot 100 is aligned with the 
conveyor access opening. Thereafter, the code wheel 60 is withdrawn 
through the slot 100 and out the access opening in the conveyor. At this 
time, the hourly character may be replaced with the current hourly 
character or any other required changes may also be effected by removal of 
old type and insertion of the appropriate current type. Preferably, 
however, at least two code wheels will be provided. During the preceeding 
production period, the replacement code wheel will be established with the 
current code for the next production sequence. Thus, after removal of one 
code wheel, the second code wheel is assembled to the sleeve in such a way 
that production down time is further minimized. The installation of the 
code wheel takes place in reverse order of the aforementioned removal. 
Therein, the U-shaped slot is roughly visually aligned with the sleeve, 
the collar 72 retracted and the code wheel 60 moved toward the sleeve 66 
with the walls 104 of the slot 100 guiding the radial motion of the code 
wheel 60 until the base 102 of the slot engages the surface of the sleeve. 
At this time, the code wheel 60 is coaxially positioned with the shaft. 
The operator then rotates the code wheel until the operator feels that the 
tips of the drive pins 94 are aligned with the flange holes 95 The code 
wheel 60 is then shifted axially to fully insert the drive pins and the 
collar 72 is released to fully lock the code wheel 30. Thus, mounting and 
removal proceeds by guided self alignment, without requiring removal of 
fasteners, and with limited dexterous movements by the operator. 
While the product coding assembly has been described with reference to 
debossing the end flap of a food carton, it should be apparent solid 
article or containers may be printed or embossed by the present assembly 
with product code as they travel along a conveyor path. Similarly, plural 
type arrays or rows of type may be incorporated for greater information 
and productivity. These and other modifications are contemplated by the 
present invention as set forth in the appended claims.