Molded bird feeder assembly

A tubular plastic bird feeder is made from a unitary blow molded enclosure which includes engageable thread patterns on one end cap and the adjacent end of the tubular body which are separated in molding by an integral annular sleeve. The sleeve is cut away circumferentially at both ends from the as-molded enclosure leaving a separated end cap which may be threaded onto the end of the tubular body. Similar integrally molded thread patterns may be formed on the other end of the unitary enclosure to provide either another removable end cap or the facility to thread another tubular body onto the end of the first tubular body to provide an extended length feeder. One embodiment includes a circular barrier disc supported in the tubular body below the lowermost seed holes to prevent seed, and other particles from accumulating in the inaccessible lower end of the feeder. In lieu of conventional seed holes cut, punched or otherwise formed in the tubular body, the body may be formed in the blow molding process to include angled seed ports with protective deflector hoods. Another embodiment includes internal and external thread patterns on one end of the tubular body to accommodate either of two seed tray constructions.

BACKGROUND OF THE INVENTION 
The present invention pertains to a tubular plastic bird feeder and, more 
particularly, to such a feeder of blow molded construction. 
Bird feeders having long hollow tubular bodies are well known in the art. 
The bodies are typically made from transparent cylindrical tubing provided 
with opposite horizontally aligned hole pairs through which bird perches 
may be inserted. A seed port is typically provided for each end of each 
perch and a conventional feeder of, for example, fifteen inches to 
eighteen inches in length may be provided with three or four vertically 
spaced perches. The opposite ends of the tubular body are closed with 
plastic or metal end caps and the upper end cap, which is removable for 
refilling, typically includes a suitable hanger. The hanger may comprise a 
wire bail or hook, piece of cord, or an integrally formed hanging bracket. 
Some tubular plastic bird feeders also include separate hooded seed ports 
which are inserted in large openings in the tube wall to facilitate 
feeding and prevent loss of seed from the downwardly descending seed 
column. 
Prior art tubular bird feeders therefore require a half dozen or more 
separate parts in the manufacture of the feeder, a number of which are 
typically made of metal. Often, the bottom end caps or closures are 
permanently affixed to the tubes and seed particles and dirt typically 
accumulate in the bottom where it is difficult to clean. 
It would be desirable, therefore, to have a plastic tubular bird feeder 
which is of simple construction, having fewer component parts and made of 
less expensive plastic materials. It would also be desirable to provide 
such a feeder in which the accumulation of seeds, seed particles and 
debris in the bottom is inhibited or which is easily accessible for 
cleaning. 
SUMMARY OF THE INVENTION 
In accordance with the present invention, a blow molded bird feeder is 
provided which is of substantially simpler and less expensive construction 
than comparable tubular bird feeders, yet provides a number of significant 
improvements and benefits. 
The molded plastic bird feeder of the present invention includes a unitary 
molded enclosure having a hollow tubular body and integral opposite end 
caps. The molded enclosure is formed with cooperating attachment means 
which are adapted to be separated after the unitary enclosure is molded to 
separate one end cap from the body. The attachment means allow the 
separated end cap to be demountably rejoined to and removed from the body, 
as for filling the feeder. The unitary enclosure is most preferably formed 
by blow molding and the attachment means preferably comprises mating screw 
threads which are formed in one of the end caps and in the tubular body. 
The attachment means may also comprise an annular sleeve which forms part 
of the unitary molded enclosure and joins the mating screw threads prior 
to separation. Alternately, the attachment means may comprise 
interengaging tabs and grooves in the end cap and in the body which are 
adapted to provide a snap fit connection therebetween. 
One of the end caps also preferably includes a through hole which is 
disposed on the longitudinal axis of the tubular body and provides an 
opening for receipt of a hanger device. In the blow molded construction, 
the through hole comprises the supply hole for the gas used in the blow 
molding process. 
In another embodiment, the tubular body includes annular rib means which 
are formed adjacent one end, and a circular disc is inserted in the tube 
and supported by the rib means to, in turn, provide support for a column 
of seed in the tubular body above the disc. The rib means may comprise a 
single rib extending radially into the tubular body and adapted to support 
the disc thereon, or may comprise a pair of ribs extending radially into 
the tubular body, which ribs are spaced to define an annular groove 
therebetween in which the disc is inserted with a snap-fit. 
In another aspect of the invention, cooperating attachment means are 
provided between both end caps and the tubular body, so that, upon 
separation, one or both of the end caps may be replaced with another 
tubular body to provide an extended length feeder. The tubular body may 
also be molded to include integral seed ports. In one form, each seed port 
comprises a groove which is defined by an upper surface and a lower 
surface joined at their radially inner edges, with the upper surface 
comprising a seed deflector hood and the lower surface defining a 
knock-out portion which provides a seed port opening. 
The present invention also includes a method for making a bird feeder which 
comprises the steps of: molding a unitary plastic enclosure which has a 
hollow tubular body and a pair of end caps, said tubular body and one end 
cap including molded attachment means; separating the end cap from the 
unitary enclosure; and engaging said attachment means to demountably 
attach the separated end cap to the tubular body. The molding step 
preferably comprises blow molding. 
In another embodiment of the invention, a modified molded enclosure 
including a hollow tubular body and single integral end cap is used to 
provide the basis for a feeder assembly which includes greater 
adaptability for the use of add on and/or replaceable parts. In this 
embodiment, the enclosure is formed with the hollow tubular body similar 
to the preceding embodiments and a single integral end cap on one end. 
Cooperating attachment means are formed on that end and are adapted to be 
separated after molding to separate the end cap from the body. The 
separated end cap may be demountably rejoined to and removed from the 
body, as in the prior embodiments, with the use of similar attachment 
means. Preferably, the attachment means comprises mating screw threads 
which are formed in the end cap and in the tubular body. Also as in the 
previously described embodiments, the attachment means includes an annular 
sleeve which forms part of the unitary molded enclosure and joins the 
mating screw threads prior to separation. 
The end of the hollow tubular body opposite the end cap is formed with 
separate attachment means, preferably screw threads, to provide 
demountable connection for an independently formed end cap. 
The upper end cap for the finally assembled bird feeder, whether formed as 
a part of an integral blow molded construction or independently formed by 
injection molding or other processes, may be formed with a small through 
hole on the longitudinal axis of the tubular body for attachment of a 
hanger device. The hanger preferably comprises a solid core flexible wire 
member which extends through the hole in the end cap and is secured within 
the cap by tying a knot or providing a bent end portion. A flexible washer 
is placed over the outer end of the wire support member in sealing 
engagement therewith and pushed down into engagement with the outside of 
the end cap. 
In a further variation, one end of the tubular body is provided with 
separate screw thread patterns formed on the inside and on the outside of 
the end. A demountable seed tray for attachment to the end of the tubular 
body may include either of two screw thread attachment patterns. If two 
seed trays are used, both of the seed trays may include an integral 
central tubular sleeve, one embodiment of which is provided with an outer 
screw thread pattern which is attachable to the inside thread pattern on 
the end of the tubular body. The tubular sleeve of this embodiment 
includes an integral cap portion which closes one end of the tubular 
sleeve and thus one end of the tubular body of the feeder. The tubular 
sleeve portion of the other seed tray embodiment has an inner thread 
pattern that is connectable to the outside thread pattern on the end of 
the tubular body. The tubular sleeve portion has a completely open 
interior which permits independent access to the inside thread pattern on 
the end of the tubular body after the seed tray is mounted thereon. In 
this manner, other elements can be added to the feeder assembly, such as 
another tubular feeder body using for example the closed end feed tray 
described above, to provide an extended length feeder. 
In a further embodiment, a molded plastic bird feeder assembly includes a 
hollow tubular body, an end cap, and a seed tray. Opposite first and 
second ends of the tubular body are provided with integrally molded 
connector means which include first interlocking connector means on the 
first end to provide either mating interlocking connection to the end cap 
or operative interlocking connection to a second end of another similarly 
molded tubular body, and second interlocking connector means on the 
opposite end of the tubular body for connection to either the seed tray or 
the first end of another similarly molded tubular body. The tubular body 
and end cap may be integrally blow molded, and the seed tray molded 
independently of the body and end cap. Alternately, the tubular body may 
be blow molded, and the end cap and seed tray molded independently. The 
interlocking connector means may comprise threaded connections or tab and 
groove connections.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
Referring first to FIGS. 1-4, the preferred embodiment of the bird feeder 
10 of the present invention will be shown in its completed and assembled 
form. The feeder is preferably formed by a blow molding process, which 
will be described later. Any suitable UV stabilized plastic material may 
be used, such as a transparent PVC. 
The feeder 10 includes a hollow tubular body 11, and integral lower end cap 
12 and a removable upper end cap 13. The upper end cap 13 is preferably 
demountably attached to the tubular body 11 by mating screw threads 
comprising an outer screw thread pattern 14 on the upper end of the 
tubular body and an inner screw thread pattern 15 on the lower end of the 
upper end cap 13. The thread patterns 14 and 15 are formed in the molding 
process to be described below. The upper end cap 15 is also provided with 
an axial through hole 16 to accommodate attachment of a hanging device, 
such as a cord or wire 17. 
The tubular body 11 includes a series of horizontally aligned hole pairs 
18, each pair adapted to receive a small diameter tube or rod 20 which is 
long enough to extend outwardly of the tubular body to form a bird perch 
on either side of the body. A pair of seed holes 21 is formed vertically 
above each perch hole pair 18 and may be suitably sized to accommodate 
different types of bird seed. As shown in FIGS. 1-3, vertically adjacent 
perch rods 20 are offset by 90.degree., such that in the particular feeder 
shown, the upper and lower perch rods are parallel to one another and the 
intermediate perch rod is perpendicular thereto. 
Referring also to FIG. 8, the lower end of the tubular body 11, just above 
the lowermost hole pair 18 is provided with a pair of integrally molded 
annular ribs 22 formed to protrude radially inwardly. The ribs 22 are 
vertically spaced to define therebetween an annular groove 23. A small 
circular disc 24 of plastic or other suitable material is inserted into 
the open upper end of the tubular body 11 and allowed to drop and rest 
upon the upper annular rib 22, as best seen in FIGS. 1 and 8. The disc 24 
supports the column of seed which fills the feeder and prevents seed, seed 
particles and dirt from entering the lower end of the tubular body and the 
hollow interior of the lower end cap 12 where it is wasted and accumulates 
and is difficult to clean out. Alternately, the upper annular rib 22 may 
be formed of a somewhat different shape including, for example, downwardly 
inclined surface portions, whereby the disc 24 could be forced downwardly 
past the upper annular rib and to snap into the annular groove 23 above 
the lower rib. In this manner, the disc 24 would be held more securely in 
place. In lieu of the annular ribs 22, integrally molded, 
circumferentially spaced bosses could also be used to support the disc. 
Referring also to FIGS. 5-7, the bird feeder 10 of the preferred embodiment 
is made from a unitary blow molded enclosure 25, the upper portion of 
which is shown in FIG. 5. The lower portion of the unitary enclosure 25 is 
as shown in the preceding drawings and includes the annular ribs 22 molded 
in the lower end of the tubular body and the integrally molded lower end 
cap 12. The as-molded enclosure 25 includes an annular sleeve 26 which 
separates the upper end cap 13 from the tubular body 11. The sleeve 26 is 
secured to the lower edge of the inner thread pattern 15 on the upper end 
cap along an annular seam 27. Similarly, the annular sleeve 26 is secured 
to the upper edge of the outer screw thread pattern 14 on the upper end of 
the tubular body by an integral annular seam 28, as best seen in FIG. 6. 
The body of the sleeve 26, between the upper and lower seams 27 and 28, is 
formed with a pair of large circular ribs 29, but the shape of the sleeve 
is not particularly important. The axial through hole 16 in the upper end 
cap 13 is formed in the blow molding process by the small tube through 
which gas is fed into the parison from which the enclosure is blow molded. 
After the enclosure 25 has been formed, the sleeve 26 is cut away along 
both the upper seam 27 and the lower seam 28, leaving the separated upper 
end cap 13 which may be threaded onto the upper end of the tubular body 11 
to close the bird feeder 10 as shown in FIG. 7. 
In an alternate embodiment, the unitary blow molded enclosure may be formed 
with a second annular sleeve (not shown) similar to the upper annular 
sleeve 26 to initially separate the lower end cap 12 from the lower end of 
the tubular body 11. Thus, as shown in FIGS. 11 and 12, a modified lower 
end cap 30 is formed with an integral outer thread pattern 31 and a 
modified tubular body 32 includes a molded inner thread pattern 33. When 
the annular sleeve is cut away (in the same manner as the upper annular 
sleeve 26 previously described), the modified lower end cap 30 may be 
threaded into the lower end of the modified tubular body 32, as shown in 
FIG. 11. In FIG. 12, the threaded upper end 14 of a previously described 
tubular body 11 or the threaded upper end of a modified tubular body 32 
may also be threaded into the lower end of the modified tubular body 32 to 
provide an extended length bird feeder. If desired, of course, a slightly 
modified bird feeder could be made from the blow molded enclosure 25 of 
the preferred embodiment (FIG. 5) by inverting the same such that the 
removable end cap is the lower end cap 12 and the upper end cap 13 is 
formed to remain integral with the tubular body 11. The modified feeder 
would have to be inverted for filling, but would otherwise be made and 
assembled in the same manner previously described. 
Instead of the threaded interconnections 14 and 15 or 31 and 33, the 
removable end cap 13 or 30 and adjacent end of the tubular body could be 
molded to include means for providing a snap fit connection therebetween. 
For example, as shown in FIG. 21 the cylindrical surface of the end cap 13 
could be provided with a number of integral tabs 49 which project radially 
inwardly to cooperate with a mating series of grooves 59 formed in the 
upper end of the tubular body and also projecting radially inwardly. As 
the cap is pushed axially onto the upper end of the tubular body 11, the 
tabs would snap into the grooves 59 as a result of the inherent 
flexibility of the plastic material, which may have a thickness of, for 
example, 0.030 inch (0.76 mm). 
A further embodiment of the invention is shown in FIGS. 9 and 10. The 
tubular body 11 may be formed in the blow molding process with indented 
portions or grooves 34. Each groove 34 is defined by a curved upper 
surface 35 and a flat lower surface 36 which are integrally joined at 
their radially inner edges along a curved edge 39. The lower surface 36 
may be molded with a scored or otherwise weakened knock-out portion which, 
when removed after molding, provides a seed port opening 38. Alternately, 
as shown, the entire flat surface 36 may be cut out, along the curved 
inner edge 39 and a continuous circular edge 37. The downwardly inclined 
curved upper surface 35 provides a deflector hood so that seeds poured 
into the upper end of the tubular body or the descending column of seeds 
consumed by birds will not pass out of the seed port openings 38. 
Although the various embodiments of the subject invention have been 
described to include a cylindrical tubular body 11, it should be 
understood that tubular bodies of any cross sectional shape may be 
utilized, including square, triangular, oblong and other shapes. All such 
shapes may be readily provided in the blow molded construction and using 
the blow molding method described. Similarly, the diameter of the tubular 
body 11, in any of various cross sectional shapes, may be made as large as 
desired. 
The embodiment shown in FIG. 13 is similar to the FIG. 5 embodiment, except 
that the FIG. 13 bird feeder 50 is molded without an integral end cap on 
one end. More particularly, the feeder 50 includes a tubular body 51 which 
is integrally joined to a lower end cap 52 by an annular sleeve 26 which 
may be identical to that shown in FIGS. 5 and 6. Thus, the tubular body 51 
includes an outer screw thread pattern 54 and the lower end cap 52 
includes an inner screw thread pattern 55. After the feeder 50 is blow 
molded, the annular sleeve 26 is separated in two places to form a parting 
seam 27 along the end of the lower end cap and a parting lip 28 at the end 
of the tubular body. The lower end cap 52 may be threaded onto the lower 
end of the tubular body 51, as previously described with the embodiment of 
FIGS. 5-7. If desired, however, the bird feeder 50 may be used as molded 
without cutting away the annular sleeve 26. 
The upper end of the tubular body 51 includes only an integral outer screw 
thread pattern 56 defining the upper opening in the tubular body and the 
point of attachment of a separately molded end cap, such as those to be 
described with respect to FIGS. 14 and 15. The open upper end of the 
tubular body also provides the opening for the gas used in the blow 
molding process. 
Referring now to FIGS. 14 and 15, there are shown two differently shaped 
end caps 57 and 58, either of which may be utilized as the upper end cap 
for the bird feeder 50 of FIG. 13, instead for example of an integrally 
molded separable end cap 52. The smaller end cap 57 includes an inverted 
cup-shaped body 60 having an inner thread pattern 61 for permitting it to 
be screwed onto the outer screw thread pattern 56 on the upper end of the 
tubular body. The cap also includes an integral downwardly extending 
conical hood 62. 
The larger end cap 58 of FIG. 15 also includes a cup-shaped body 63 which 
is somewhat deeper than the body 63 of the FIG. 14 cap. The body 63 
includes an inner thread pattern 64, also adapted to mate with the screw 
thread pattern 56 at the top of the tubular body 51. A somewhat larger 
integral hood 65 is provided on the larger end cap and provides protection 
against rain and snow entering the seed ports. Both end caps 57 and 58 may 
be made of plastic by injection molding or could be made of metal or other 
material, if desired. 
Each of the end caps 57 and 58 includes a central through hole 66, located 
similarly as the axial through hole 16 in the end cap 13 previously 
described, for the purpose of attaching a feeder hanger. The hanger 
preferably comprises a relatively rigid length of wire 67 which is knotted 
or otherwise bent at its lower end 68 to secure the hanger in place as the 
wire is inserted upwardly through the hole 66 in the end cap. By 
connecting the hanger in this way, the feed tube can be unscrewed from the 
cap without disturbing the attachment of the cap and hanger wire to the 
feeder support structure. On the outside, a flexible washer 70 is slipped 
onto the wire 67 and down into contact with the top of the end cap to 
provide a water tight seal. One preferable form of the wire hanger 67 is 
18 gauge solid copper wire covered with a plastic coating. The washer 70 
is preferably a neoprene washer. Braided or twisted cord materials may 
also be used as a hanger. 
In FIGS. 16 and 17, there is shown another embodiment of a tubular body 71 
which provides a much greater adaptability for the connection of accessory 
pieces to vary the size, capacity and functionality of the bird feeder in 
which it is used. The main portion of the body 71 may include conventional 
seed holes and opposite hole pairs for a perch rod, as previously 
described with respect to other embodiments. The upper end of the tubular 
body 71 is provided with an outer screw thread pattern which may be 
identical to the pattern 14 formed in the tubular body 11 of FIGS. 5-7 or 
the upper thread pattern 56 formed in the tubular body 51 of FIG. 13. 
Correspondingly, any of end caps 13, 57 or 58 may be utilized therewith to 
provide an upper closure for a bird feeder utilizing tubular body 71. 
The lower end of the tubular body 71 is provided with an inside thread 
pattern 75 and an outside thread pattern 76. The outside thread pattern 76 
may be similar to the outer screw thread pattern 54 in the tubular body 51 
of FIG. 13 and formed in a similar manner. Thus, the outside thread 
pattern 76 may be adapted to accommodate an integrally formed and 
subsequently separated lower end cap 52 of the FIG. 13 embodiment or some 
other type of separately molded threaded end cap. 
Referring to FIG. 18, the outside thread pattern 76 may also be utilized to 
accommodate attachment of a seed tray 77. This seed tray is preferably 
made of an injection molded construction and includes a shallow lower tray 
portion 78 which surrounds a central upwardly extending tubular sleeve 
portion 80. The sleeve portion includes an inner thread pattern 81 
allowing the tray 77 to be threaded onto the outside thread pattern 76 on 
the end of the tubular body 71. The interior of the tubular sleeve 81 is 
completely open to allow independent access to the inside thread pattern 
75 after the seed tray 77 has been attached. The inside thread pattern 75 
is designed to accommodate attachment of another tubular body, such as by 
means of the outer screw thread pattern 56 on the upper end of tubular 
body 51 in FIG. 13. In this manner, an extended length bird feeder may be 
provided, similarly to the embodiment described above and shown in FIG. 
12. 
Alternately, the inside thread pattern 75 may 20 be utilized to accommodate 
a seed tray 82 shown in FIG. 19. Seed tray 82 also includes a lower tray 
portion 83 and an integral upstanding tubular sleeve 84. The tubular 
sleeve is provided with an outside thread pattern 85 adapted to cooperate 
with and provide connection to the inside thread pattern 75 in the tubular 
body 71. The top of the tubular sleeve 84 includes an integral closure 
face 86 to enclose the bottom of the tubular body and retain the seeds 
therein. The closure face 86 may include a series of moisture relief holes 
87 to help dispel any moisture which may accumulate in the tubular body. 
The tray portion 83 includes a series of drain holes 88 to drain rain 
water which might otherwise accumulate in the tray. Similar drain holes 
are provided in the seed tray 77 of FIG. 18. 
An integral post sleeve 89 may be located coaxially within the tubular 
sleeve 84 and depend downwardly from its connection with the closure face 
86. The bottom of the post sleeve 89 is open to allow the tray and the 
attached feeder assembly to be mounted on a suitable supporting post. 
Preferably, a series of circumferentially spaced reinforcing ribs 90 
connects the upper end of the post sleeve 89 to the underside of the 
closure face 86.