Baffle for coolant passage

A baffle for partitioning fluid circulating passages that are provided in a structure for heat transfer purposes. The baffles are inserted without the need for extra drilling and tapping of the structure, and include an elongated, substantially flat body which is inserted into a passage to thereby partition the passage into two conduits, which act as supply and return conduits for fluid flow. The baffle further extends into another passage, through which fluid flows, to thereby block the flow of fluid and force the fluid to flow through the partitioned passage via the defined conduits. The baffle is held into position by resilient arms which project outwardly from the baffle and are received fully within the non-partitioned passage.

BACKGROUND OF THE INVENTION 
The present invention pertains to baffles, and in particular to a baffle 
for plastic injection molds and the like to circulate coolant. 
In plastic injection molds and the like a heated material, such as plastic, 
is injected into the mold to thereby form the material into a particular 
shape. Molds are further provided with a network of passages which are 
utilized to effectuate heat transfer purposes. Typically, the fluid is 
used as a coolant means, however, there are certain occasions where the 
fluid may be used to supply heat, such as near the runners of a mold. In 
either case, the configuration of the item needing cooling (or heating) 
often requires that some passages be provided with only one opening. 
Obviously, it is preferred, to drive the passage entirely through the die 
or mold so that an inlet and outlet port may be provided to facilitate 
flow of the fluid therethrough. Yet, when the passage has only one 
opening, fluid will not flow therethrough without some intervention. 
Prior artisans have inserted baffles into these passages to thereby divide 
them into two conduits The two conduits would run the length of the 
passage and be fluidly connected at the end wall of the passage. The 
conduits then would function as fluid supply and return channels for the 
passage. To direct the water through the conduits, the baffle would extend 
into a passage through which the flow of fluid existed and therein provide 
a barrier which would block the flow in that passage. The flow then would 
be directed around the baffle via the conduits before, once again, 
returning to the normally flowing passage. 
In the past, the insertion of these baffles has been a problem. Typically 
an access opening is drilled into the die or mold opposite the passage to 
be partitioned. The opening is subsequently tapped in preparation for 
insertion of the baffle. Once this is accomplished the baffle can then be 
inserted into the passage through the access opening. Prior baffles are 
provided with plugs which are threadedly received into said openings so 
that the circulating fluid is not lost therethrough. 
This system, while being functional, is time consuming and expensive. 
Furthermore, there is the ever present nuisance of fluid leakage through 
the extra openings. Hence, a new baffle and method of insertion has been 
in great need in the industry. 
SUMMARY OF THE INVENTION 
In the present invention, the baffles are inserted into the passages with 
only one opening, without the need for the drilling and tapping of access 
openings. The baffle is provided with means which project into the 
normally fluid flowing passage to thereby hold the baffle in its proper 
position. The means permits the baffle to be inserted through the passage 
to be partitioned, toward the fluid flowing passage, thereby obviating the 
need for an access opening. 
In the preferred embodiment, the means includes at least one resilient arm 
which projects outwardly from the baffle's body near or at the end which 
functions as a barrier in the fluid flowing passage. The at least one arm 
projects outwardly beyond the passage sidewall in its unbiased state, but 
readily flexes inwardly toward the baffle's body to permit insertion of 
the baffle within the passage. 
By using the baffle of the present invention the set up of the mold or die 
may be completed much quicker and more economically than by means 
previously available. Not only is the operation enhanced by the 
elimination of the drilling and tapping steps but also, by the fact that 
the insertion of the present baffles, which insert with a simple pushing 
operation, is quicker than the previous threading of each baffle into its 
respective opening. Also, the proper positioning of the present baffle is 
more easily accomplished than in the past, due to the fact that the baffle 
is merely inserted until the end abuts the far wall (i.e., the end acting 
as a barrier). This arrangement completely eliminates any guess work in 
determining the distance to insert the baffle into the passage. 
Furthermore, since the user can visually see the baffle body (instead of 
only the plug) the proper alignment of the baffle is more easily 
accomplished by the operator. Lastly, without the extra openings created 
by the drilling, the likelihood of fluid leakage is reduced.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
In the preferred embodiment, baffle 30 is inserted into a fluid circulating 
passage 15 provided with only one opening. Baffle 30 includes an elongate, 
substantially flat body 31 that extends along the width of passage 15 to 
partition it into two parallel conduits 20, 21 fluidly coupled at the end 
wall 18 (FIG. 3). Body 31 also extends into a passage 10, through which 
fluid normally flows, and completely blocks the flow of fluid therethrough 
so that the fluid is forced into passage 15. To hold the baffle in its 
proper position a pair of resilient arms 41 project out from body 31 and 
are received within passage 10. Arms 41 are shaped to engage the sidewall 
of passage 10 to preclude baffle 30 from being forced upwardly (as seen in 
FIG. 3) or twisting sideways. 
The mold 1 is generally illustrated as two portions 2, 3 joined together. 
In the preferred embodiment, lower portion 2 represents the manifold or a 
part of the mold and upper portion 3 represents the mold or another part 
of the mold, respectively. In any event, mold 1 includes a first passage 
10 which is provided with an inlet and outlet port 11, 12. Ports 11, 12 
fluidly connect to supply and return lines in a conventional manner and 
thereby establish a flow of fluid through passage 10. Extending upwardly 
(as illustrated in the figures) from passage 10 is a second passage 15 
which is provided with only one opening. Second passage 15 has a first end 
16 which opens into a sidewall of passage 10 and a second end 17 which is 
closed by end wall 18. 
Baffle 30 is generally composed of a plastic material, such as nylon, but 
could be composed of a variety of materials possessing the requisite 
characteristics. As can be seen in FIG. 1, baffle 30 comprises an 
elongated, substantially flat body 31. Body 31 is shaped to have a width 
substantially equal to the width of passages 10 and 15. Body 31 is further 
provided with first and second edges 32, 33 which are adapted to snugly 
engage opposite sidewalls of passage 15 when baffle 30 is inserted 
therein. A first end 36 of body 31 is received through passage 15 and into 
passage 10. First end 36 is configured to engage the entire periphery of 
passage 10 that is opposite passage 15. In the preferred embodiment, first 
end 36 is provided with a semicircular end to correspond to the circular 
shape of passage 10 (FIG. 4). More specifically, first and second edges 
32, 33 are arcuately shaped at first end 36 to so define the semicircular 
configuration. Baffle 30 then completely blocks passage 10 and prohibits 
the fluid from flowing directly through massage 10 from inlet port 11 to 
outlet port 12. 
As stated above, baffle 30 extends across the width of passage 15 and 
thereby partitions it into two parallel conduits 20, 21. When inserted, 
baffle 30 is provided with a second end 37 which extends upwardly from 
passage 10 to a point just short of end wall 18 (FIGS. 3 and 4). The gap 
38 defined by second end 37 and end wall 18 acts to fluidly connect the 
two conduits 20, 21. 
As seen in FIG. 3, baffle 30 effectively directs the fluid to flow through 
second passage 15 and thereby facilitates the needed heat transfer with 
(for example) the molded part. The flow of fluid (as illustrated by arrows 
25) enters passage 10 via inlet port 11 and continues therethrough until 
encountering baffle 30. At this point, the fluid is forced to flow into 
the supply conduit 20 in a direction toward end wall 18. Upon reaching 
second end 37 of baffle 30, the fluid flows through gap 38 and into return 
conduit 21 which directs the flow back to passage 10 where it then goes to 
outlet port 12. 
To keep the flow of fluid from forcing baffle 3 out of passage 10 or from 
twisting sideways therein, which would frustrate the flow pattern 
discussed above, baffle 30 is provided with a means 40 for holding it into 
its proper position. Holding means 40 is fully received within passage 10 
and cooperates therewith to maintain baffle 30 in position. 
In the preferred embodiment, holding means 40 includes a pair of resilient 
arms 41 which are attached to first and second sidewalls 34, 35 of baffle 
30, and project outwardly therefrom. Arms 41 are arcuate in shape and 
include a first attached end 42 and a second free end 43. Further, arms 41 
are curved, with a gradually sloping surface 44, so that their free ends 
43 project in the direction toward second end 37. 
Resilient arms 41 are constructed so that they project outwardly a combined 
distance which is greater than the width of passage 15. Hence, when baffle 
30 is inserted into passage 15, arms 41 engage the sidewalls thereof and 
due to the gradually sloped surface 44 are easily biased inwardly toward 
body 31 (FIG. 5). At the point where first end 36 abuts the sidewall of 
passage 10, arms 41 are fully received within passage 10 and expand 
outwardly to their unbiased position. Arms 41, when properly positioned, 
extend directly upward (as seen in FIG. 5) and engage the sidewall of 
passage 10 adjacent to first end 16 of passage 15. In this position arms 
41 lie in a plane that contains the longitudinal axis of both passages 10 
and 15. Free ends 43 of arms 41 therefore engage the most upward point of 
the sidewall of passage 10 (as seen in FIG. 5). This positioning of arms 
41 precludes baffle 30 from being forced out of its proper position. The 
square engagement of free ends 43 with the sidewall of passage 10 keeps 
baffle 30 from being forced out of passage 10 toward end wall 18. Also, 
because free ends 43 engage the most upward portion of the sidewall of 
passage 10 (as illustrated in FIGS. 3 and 5), the arms hold baffle 30 from 
twisting sideways. The twisting motion is resisted by arms 41, because to 
so twist baffle 30 would require arms 41 to be bent downward along the 
sidewalls of passage 10. Therefore, arms 41 simply and securely hold 
baffle 30 in place. 
Body 31 is shaped so as to be thicker along its longitudinal axis than 
along its edges 32, 33 (FIG. 1). Each of the sidewalls 34, 35, then, 
include first and second inclined surfaces 48, 49 that meet at the body's 
longitudinal axis and form thereat a ridge 50. This configuration of body 
31 adds extra strength and rigidity thereto, to ensure that it is not 
deformed out of shape or position by the fluid flow or during insertion of 
the baffle 30. 
The assembly of baffle 30 is accomplished in an easy and quick manner. As 
best seen in FIG. 1, mold 1 is composed of upper and lower portions 2, 3. 
Second passage 15 is included in both portions in such a way that its 
first end 16 is contained in lower portion 2. Before upper portion 3 is 
mounted on lower portion 2, baffle 30 is inserted into passage 15 
downwardly toward passage 10. As first end 36 of baffle 30 is pushed into 
passage 15, sloping surfaces 44 of resilient arms 41 are engaged by rim 19 
of passage 15. This engagement biases resilient arms 41 inwardly as baffle 
30 is pushed through passage 15 until first end 16 abuts the far sidewall 
of passage 10. At this point, arms 41 spring back into the unbiased 
position to thereby hold the baffle in its proper position. Since ends 43 
of arms 41 are designed to engage the uppermost surface of passage 10 (as 
illustrated in the Figures), arms 41 will only spring back when baffle 30 
has been properly positioned. If the baffle is not positioned squarely so 
as to completely block passage 10, the operator need only twist baffle 30 
until arms 41 spring back and baffle 30 can no longer be removed. Once all 
of the baffles have been thusly inserted, upper portion 3 may be attached 
to lower portion 2 by any well known means. It is noted, that since 
passage 15 extends through both portions, that the two portions are sealed 
by any conventional means, such as by O-ring 6 (FIG. 1). As can be seen, 
therefore, baffle 30 may be inserted into mold 1 in a quick and easy 
manner. 
Of course, it is understood that the above is merely a preferred embodiment 
of the invention, and that various other embodiments as well as many 
changes and alterations may be made without departing from the spirit and 
broader aspects of the invention.