Carton with venting arrangement

A venting arrangement in a carton with a top panel and two side panels forms an opening in the carton to facilitate the escape of gas from the interior of the carton. The venting arrangement comprises at least one vent flap defined by two perforated lines and one fold line in a carton panel. The vent flap is separated along the perforated lines and folded about the fold line to move the vent flap out of the plane of carton panel to form the gas relief opening in the carton.

BACKGROUND OF THE INVENTION 
The present invention relates to a carton having a at least one vent. More 
particularly, the invention relates to a carton having at least one vent 
formed by tearing and folding portions of the carton along perforated and 
fold lines to permit the escape of gas. 
In cartons or containers packaging items such as frozen foods, it is highly 
desirable for the same carton to be used for cooking the food as well as 
protecting it during shipment and display. When the carton is used for 
cooking the food contained therein, the carton must be adequately vented 
to permit such gases as steam and water vapor formed from heating the food 
to escape from the interior of the carton. If the gases are not permitted 
to escape, such gases as steam and water vapor may cause the food to 
become soggy and unappetizing. 
For example, if a piece of frozen pizza is contained within the carton and 
placed within a conventional or microwave oven, the steam or water vapor 
created during cooking would make the crust of the pizza soggy. This 
problem is alleviated by providing adequate vents in the carton which may 
be opened just prior to cooking to permit the escape gases during cooking. 
Such vents must remain closed during shipment and display to prevent 
contamination of the food in the carton and must be easily and simply 
opened without undue force. Additionally, the construction and location of 
the vents should not impair the structural integrity of the carton and not 
damage the food upon opening. 
SUMMARY OF THE INVENTION 
Accordingly, it is an object of the present invention to provide a venting 
arrangement for a carton which is simple, quick and inexpensive to operate 
and manufacture. 
Another object of the present invention is to provide a venting arrangement 
for a carton which will remain closed during shipment and display and will 
not accidentally open. 
A further object of the present invention is to provide a venting 
arrangement for a carton which will not damage the contents of the carton 
upon opening and will not impair the structural integrity of the carton. 
The foregoing objects are attained in a carton including a top panel and 
first and second adjacent side panels hingedly coupled along fold lines, 
the improvement comprising venting means formed in the panels for opening 
the carton to facilitate the escape of gas from the interior of the carton 
comprising a first perforated line extending along a portion of a fold 
line hingedly coupling two of the panels, a second perforated line formed 
in one of the two panels and extending at one end from one end of the 
first perforated line, a first fold line joining the other two ends of the 
first and second perforated lines, and a vent flap defined in the one 
panel by the first and second perforated lines and the first fold line, 
which vent flap may be pivoted about the first fold line out of a plane 
containing the one panel after separation of the vent flap from the 
remainder of the one panel upon tearing of the first and second perforated 
lines. 
By forming the venting means for the carton of the present invention in 
this manner, a carton may be adequately vented, when desired, by tearing 
the carton along the perforated lines and folding the vent flap about its 
fold line out of the plane of the panel in which it is formed to provide 
an opening in the carton. Additionally, the vents are so located and 
arranged so as not to impair the structural integrity of the carton either 
in its open or closed position and so as not to damage the food contents 
upon opening of the vents or during shipment and display. 
Other objects, advantages and salient features of the present invention 
will become apparent from the following detailed description, which taken 
in conjunction with the annexed drawings, discloses preferred embodiments 
of the present invention. 
As used in the application, the terms "top", or "side", and "bottom" are 
intended to facilitate the description of the carton. Thus, such terms are 
merely illustrative of the carton and are not intended to limit the carton 
to any specific orientation. 
As used herein, the term "gas" means all gaseous substances including water 
vapor and steam. The term "carton" covers any configuration of the carton 
including the blank and any partially assembled or collapsed form thereof.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS OF THE INVENTION 
Referring initially to FIGS. 1-4, the carton 10 is in the form of a hollow 
parallelopiped having six planar sides with a top panel 12, four side 
panels 14, 16 (only two of which are illustrated), and a bottom panel (not 
illustrated). The panels are rectangular and are hingedly coupled along 
respective fold lines. The carton may be formed of any suitable foldable 
paperboard, depending upon the size, weight and nature of the item or 
items to be contained within the carton 10. 
Fold lines 18, 20, 22 hingedly couple the top panel 12 to the first side 
panel 14, the top panel 12 to the second side panel 16, and the first side 
panel 14 to the second side panel 16, respectively. The carton 10 may be 
formed in any suitable manner and may include folding and/or tear panels 
to facilitate sealing and opening. 
In the embodiment of FIGS. 1-4, the two venting arrangements 24 are formed 
in opposite corners 26 of the top panel 12. The corners 26 form the 
juncture of two side panels and the top panel. 
As shown in detail in FIG. 2, each venting arrangement 24 comprises a first 
perforated line 28, a second perforated line 30 and a first fold line 32. 
Since each of the venting arrangements 24 is identical, only one will be 
described in detail. 
The first perforated line 28 is formed along the fold line 18 between the 
top panel 12 and the first side panel 14. One-half of the first perforated 
line 28 comprises a series 34 of perforations formed in the fold line 18. 
The series 34 extends from the corner 26 approximately half the length of 
the first perforated line 28. The second half of the perforated line 28 
comprises a slit 36 cut into the material of the carton 10 and is defined 
by a bottom edge 38 and two side edges 40. The bottom edge 38 is located 
below the series 34. The slit 36 extends between the end of the series 34 
and the second perforated line 30. 
The second perforated line 30 is arcuate and comprises a series of 
perforations arranged along a 90.degree. arc having corner 26 as the 
center of curvature. The second perforated line 30 is formed in the top 
panel 12 and extends from the end of the first perforated line 28 remote 
from the corner 26. 
The first fold line 32 constitutes the end portion of the fold line 20 
located adjacent the corner 26. The first fold line 32 joins the first 
perforated line 28 at the corner 26 and the second perforated line 30 at 
the end thereof remote from the first perforated line 28. 
The portion of the top panel 12 enclosed by first perforated line 28, the 
second perforated line 30 and the first fold line 32 defines a vent flap 
44. The vent flap 44 is in the shape of a sector having a 90.degree. 
inclined angle. The vent flap 44 has a gripping tab 46 which extends over 
the slit 36 and forms the top edge thereof. The gripping tab 46 is formed 
by the portion of the carton which is cut out by the edges 38, 40 to form 
the slit 36. As will be explained in more detail later, the gripping tab 
46 facilitates the opening of the vent arrangement 24. 
During shipment and display of the carton 10, the venting arrangement 24 is 
in the closed position illustrated in FIG. 2. The venting arrangement 24 
is opened just before placing the carton 10 within a conventional or 
microwave oven. 
The carton 10 may be opened by placing a fingernail within the slit 36 and 
gripping the opposite surfaces of the gripping tab 46. Once the tab 46 has 
been securely gripped, the vent flap 44 is lifted by tearing the vent flap 
44 from the remainder of the top panel 12 along the perforated lines 34, 
30 as illustrated in FIG. 3. The vent tab 44 is then pivoted about the 
first fold line 32 upwardly and out of the plane of the top panel 12 to 
provide an opening 48 in the top panel 12 as illustrated in FIG. 4. The 
opening 48 permits gas to escape from the interior of the carton during 
cooking. 
Referring now to FIGS. 5-8, a second embodiment of the present invention is 
illustrated. In this embodiment, the venting arrangements 52 are formed at 
opposed side edges of the top panel 12 between the corners thereof. The 
features of the carton 50 which are identical to those of carton 10 of 
FIGS. 1-4 are denoted with like reference numerals. Accordingly, those 
portions will not be discussed further. Since each of the venting 
arrangements 52 are identical, only one will be described in detail. 
The venting arrangement 52 comprises four perforated lines 54, 56, 58, 60 
and four fold lines 62, 64, 66, 68. These perforated lines and fold lines 
define four triangularly shaped vent flaps 70, 72, 74, 76. The first and 
third perforated lines 54,58 are colinear and are formed in the fold line 
18 between the top panel 12 and the first side panel 14. The second and 
fourth perforated lines 56, 60 are perpendicular to the first and third 
perforated lines 54 and extend in the panels 12, 14, respectively. The 
perforated lines 54, 56, 58, 60 meet at and radiate from a common juncture 
78 on the fold line 18 and are each equal in length. 
Similarly, each of the fold lines 62, 64, 66, 68 are equal in length. The 
first fold line 62 joins the free ends of the first perforated line 54 and 
the second perforated line 56. The second fold line 64 joins the free ends 
of the second perforated line 56 and the third perforated line 58. The 
third fold line 66 joins the free ends of the third perforated line 58 and 
the fourth perforated line 60. The fourth fold line 68 joins the free ends 
of the fourth perforated line 60 and the first perforated line 54. 
The venting arrangement 52 spans the juncture of the panel 12, 14 in that 
the first and second vent flaps 70, 72, the fold lines 62, 64 and the 
perforated line 56 are located in the top panel 12 while the third and 
fourth vent flaps 74, 76, the fold lines 66, 68 and the perforated line 60 
are formed in the side panel 14. As noted above, the perforated lines 54, 
58 are located along the juncture line of the top panel 12 and the side 
panel 14. 
As illustrated in FIG. 7, when the venting arrangement 52 is formed in the 
carton blank, the fold lines 62, 64, 66, 68 form a square or diamond shape 
with equal sides and 90.degree. included angles. The first and third 
perforated lines 54, 58 form a first diagonal and the second and fourth 
perforated lines 56, 60 form a second diagonal across the square formed by 
the fold lines 62, 64, 66, 68. 
In the closed position of the venting arrangement 52 illustrated in FIG. 6, 
the vent flaps 70, 72 are coplanar with the top panel 12 and the vent 
flaps 74, 76 are coplanar with the side panel 14. In this position, the 
perforated lines 54, 56, 58, 60 are intact. To open the vent 52, downward 
and inward pressure is exerted on the juncture 78 of the perforated lines 
54, 56, 58, 60. This pressure forces the perforated lines 54, 56, 58, 60 
to tear, thereby separating the vent flaps 70, 72, 74, 76 from each other. 
The vent flaps 70, 72, 74, 76 then pivot downwardly and inwardly about the 
fold lines 62, 64, 66, 68, respectively to form an opening 80 in the 
carton 50. The opening 80 is formed just prior to placement of the carton 
50 within a conventional or microwave oven in order to cook the contents 
of the carton 50. 
While particular embodiments have been chosen to illustrate the invention, 
it will be understood by those skilled in this art that various changes 
and modifications can be made therein without departing from the scope of 
the invention as defined in the appended claims.