US 3760874 A
A heat exchange fluid baffle for assuring that heat exchange fluid travels over a lengthened path through mold apertures that are used for controlling the temperature of the plastic or other material being molded in the mold. The baffle comprises an extruded blade. The blade comprises a main central body section that has spaced apart longitudinal edges with sufficient flexibility to bend and spread as the blade is press fitted into the aperture. A passageway at the inner side of the blade enables the fluid to pass around the blade in going from the fluid intake opening to the fluid exit opening. A separate pipe threaded plug closes the aperture through which the blade is inserted.
Description (OCR text may contain errors)
United States Patent Boskovic Sept. 25, 1973 i 1 HEAT EXCHANGE FLUID BAFFLES Primary Examiner-Manue1 A. Antonakas  Inventor: Borislav Boskovic, 4734 N. Talman, Attorney-71mm Alter et Chicago, 111. 60625 22 Filed: Feb. 28, 1972 1 ABSTRACT 2 1 App]. 229 0 A heat exchange fluid baffle for assuring that heat exchange fluid travels over a lengthened path through mold apertures that are used for controlling the tem-  [1.8. Ci. 165/177, 138/38 perature of the plastic or other material being molded  Int. Cl F28f 1/40 in he mold The baffle Comprises an extruded blade.  Field Of Search 165/1, 174, 177; The blade comprises a main central body Section that 219/302; 138/37 38 has spaced apart longitudinal edges with sufficient flexibility to bend and spread as the blade is press fitted  References Cned into the aperture. A passageway at the inner side of the UNITED STATES PATENTS blade enables the fluid to pass around the blade in 977,927 12/1910 Bugnon 165/177 x g g from the fluid intake Opening to the fluid exit opening. A separate pipe threaded plug closes the aper- FOREIGN PATENTS OR APPLICATIONS ture through which the blade is inserted. 246,211 12/1946 Switzerland 165/177 10 Claims, 6 Drawing Figures HEAT EXCHANGE FLUID BAFFLES This invention is generally concerned with liquid bafflearrangements and, more particularly, although not exclusively, with heat exchange fluid baffles of the type used in plastic, die casting, or other mold apertures to control the temperature of the casting material being molded- It is oftentimes necessary to control the temperature of material being molded to either keep the material from setting or to cause it to set. Examples of where such temperature control is necessary is at the runners of the mold to keep the material from setting in the runners. On the other hand, it is desirable to cause the casting, or molded material, to set as fast as possible in the mold form itself. Thus, at times it is necessary to heat the casting, or molded material, in the runners and at other times it is necessary to cool the material in the mold cavities.
. It has been found that the temperature can be controlled using heat exchange fluid and forcing the heat exchange fluid through apertures in the mold that are in proximity to the actual cavities of the mold.
In the utilization of heat exchange fluid for controlling the temperature of the mold, the heat exchange apertures are drilled into the mold where desired and a flow aperture is drilled serially to the heat exchange aperture to form a heat exchange fluid passageway whereby water or other heat exchange media could be passed through the connected apertures in a continuous stream to enable the maximum transfer of heat.
Before too long, baffle arrangements were used in the heat exchange apertures to assure that the heat exchange medium travelled over the maximum length pathand that the maximum heatexchange efficiency was thereby obtained. Among the prior art baffle arrangements used have been brass baffle blades braised onto brass plugs to cause the heat exchange fluid to follow a tortuous path.
One of the problems of these brass baffle blades was in obtaining proper alignment of the blade in the aperture so that the broad side of the blade facedthe connecting passageways. Eventually, this problem was overcome by making a mark on the outside portion of the threaded plugs to indicate the position of the blade. Even then, it-was found that, on occasions, to properly seat the plug in the threaded portion of the aperture, it was necessary to misalign the baffle blade. In addition, the brass baffle blade was expensive to manufacture and oftentimes did not provide a truly efficient seal. Further difficulties were encountered when the brass blade was too large, which occurred quite often unless the tolerances on the blades and holes were kept within machine tool limits.
Before too long, plastic baffle blades were used to overcome some of the difficulties heretofore encountered by the brass or other metallic baffle blades. The plastic baffle blades which were used were less expensive than the metal blades. However, they also presented problems. Among the problems encountered were the facts that when the plastic blade was sufliciently large to achieve a good seal, then oftentimes in tightening the plugs affixed thereto the plastic blade would get caught on the peripheral of the aperture and break. To complicate matters and compound the damage, the break was not discemable when the plug was integrally connected with the blade.
Another blade with the plastic blades heretofore used was that, because of the integral connection between the baffle blade and the pipe threaded plug, it was relatively costly to manufacture baffle blades of different sizes.
Accordingly, an object of the present invention is to provide a new and unique baffle arrangement for utilization in the apertures used in controlling the temperature of mold parts.
A related object of this invention is to provide an inexpensive baffle blade that is easy and efficient to use.
Yet another object of the present invention is to provide a baffle blade of the above-noted type that assures a near perfect seal.
Still another object of the invention is to provide a baffle blade that is made from extruded material and thus is relatively inexpensive. Further, the extruded baffle blade is not integrally connected to a plug.
Another object of the invention is to provide a baffle blade which can fit a great many different sized apertures and provide the tortuous path necessary for efficient heat exchange.
An object related to the above-mentioned and enumerated objects is to provide baffle blades of extruded plastic or other suitable materials that can be cut to the desired length.
Still another object of the invention is to provide baffle blades which have split edges shaped so as to form a multiplicity of tortuous paths rather than only an inand-out path.
In accordance with a preferred embodiment of this invention, the baffle blade is fabricated from an extruded material, such as plastic aluminum, brass, or the like. The blade comprises a main body section having split longitudinal ends which assume a V-like shape. The inner side of the baffle blade, when it is in the aperture, has a conformed notch therein to assure the passage of the heat exchange medium, such as water, around the baffle blade. The baffle blade, in the preferred arrangement, is positioned in the aperture with its widest side facing the water inlet. The baffle blade is pressfitted into the aperture and as it is pressed in there is sufficient flexibility so that the split longitudinal edges spread to form a practically perfect seal assuring that the intake exchange fluid goes around the baffle blade and through the notch back up towards the outer portion of the baffle blade to the outlet opening of the aperture.
Other objects and features of the invention will become apparent from the following description of the invention made with the aid of the accompanying drawings wherein:
FIG. 1 is a cross-sectional view of the heat exchange fluid pathways in the mold jackets with a baffle blade in place;
FIG. 2 is a pictorial view of the baffle blade and the separate plug used therewith;
FIG. 3 is a view of the bottom of the broad side of the baffle blade;
FIG. 4 is a bottom view of one embodiment of the blade in the aperture;
FIG. 5 is a bottom view of another embodiment of the blade wherein a plurality of the paths along the length of the blade can be connected in series to form an even longer baffle path; and
FIG. 6 is a bottom view of yet another embodiment of the baffle blade.
FIG. 1, in a more or less schematic representation shows a mold block 11 having a baffle arrangement forming a heat exchange coolant pathway 12 therein. The pathway comprises an intake aperture 13 and an outlet apeture 14. Arrows, such as arrow a, trace the path of the heat exchange coolant through the baffle arrangement. An aperture 16 bored from the side of the mold block connects the inlet aperture 13, the heat exchange aperture 17, and the outlet aperture 14 through portion 15 of aperture 16. Note that the connecting aperture 16 is shown as being blocked by pipe threaded plug 18.
Aperture 17 is the aperture that is in proximity to the part of the mold whose temperature is being controlled. As can be seen, a baffle arrangement is provided in aperture 17. The baffle comprises a baffle blade generally shown as 19, comprising a main body section shown in cross-section 21 and having split longitudinal ends 22 spaced apart from split end 23.
It should be noted that, as the blade is pressed into aperture 17, the bottom split ends come into contact with the bottom of the aperture and are spread out even more, such as at 24. This enables utilization of baffle blade 19 in holes of varying depths.
Means, such as notch 26, at the inner side of the baffle blade, is shown providing a path for the heat exchange liquid that follows the tortuous path necessitated by the baffle blade. The-baffle blade 19 is held in place in the heat exchange aperture using a well known pipe threaded plug, such as plug 27. The plug 27 also blocks the aperture 17.
In FIG. 2 the actual split longitudinal edge is better seen as approximating a V shape. Therein is shown the main body 21 and split longitudinal edges 22 and 23. The advantage of this type of an edge is readily discernible in that, for example, it is known that, unless great care is exercised, the tolerances of apertures in the mold block vary quite a bit. Thus the baffle blade will either be too large or too small to properly fit into the aperture. If the blade is without the split ends and is too large, it tends to break. If the blade without the split ends is too small, it does not seal.
There are baffle blades on the market wherein the blade is made of plastic with the center of the blade body being thicker than its edges. In theory these presently available baffle blades, which are integrally connected to a threaded pipe plug, turn or twist as the plug is being tightened. The blade edges flex so as to provide a good seal. However, to be practical, the width of the blade is often less than the diameter of the aperture. Thus, the coolant fluid can leak through the clearance space between the edges of the blade and the inside periphery of the aperture. As the blade becomes longer and the impedance to coolant flow increases, the leakage also increases.
With the split edges shown and explained herein, this problem is overcome because not only is the blade not turned, but it is placed in its proper broadside position relative to the inlet and the outlet aperture and pressfitted into the baffle aperture. The press fit causes the split edges to spread apart forming a good seal and providing a built-in tolerance so that the precision of a machinist in making the aperture or blade is not necessary.
In a preferred embodiment, the blade 19 is preferably extruded in large lengths. To use the extruded blade, it is cut to size and the notch, such as notch 26, is cut in on site. The notch can have any configuration as shown with the V-shaped notch 26 of FIG. 2 and the arcuate notch 26-A of FIG. 3.
A further advantage of the baffle system utilizing the split edged baffle blades is that, if the baffle blade is slightly longer than the baffle aperture, then the edges, such as edge 28 and 29, will bend and collapse because of the flexibility of the material. Thus, a blade slightly longer than the depth of the aperture can be used further diminishing the necessity of maintaining rigid tolerances.
FIGS. 4, 5 and 6 show different embodiments. In the embodiment of FIG. 4, a straight extruded piece is shown. Herein the advantage lies in the use of the extruded material cut to the proper lengths on site because the extruded blade is not an integral part of the plug or integrally connected to the plug. The blade 19 can be properly positioned broadside to the fluid inlet and outlet and can be positioned without any danger of unknown breakages.
FIG. 5 shows an exaggerated extrusion wherein a plurality of baffle paths are serially connected to provide an extra long pathway. For example, the liquid enters quadrant A through inlet aperture 16. At the inner side of the split longitudinal edge 22a is a notch 30 which enables the fluid to flow into quadrant B and then outward towards the outer portion of the baffle blade and through a notch 31 at the outside of the split longitudinal edge 22 to quadrant C through which the fluid once again flows inward through notch 32 in edge 23 into quadrant D and out through outlet 14, as shown by the arrows. Thus, in quadrant A the liquid flows into the mold block. In quadrant B the liquid flows toward the outside of the mold block or towards the viewer. Then, through the notch at the top of side 31 at the outside of side 31 and back towards the inside of a block and in quadrant C and through a notch or opening 32at the bottom of split end 23 and out towards the outside of the block in quadrant D through outlet 14. It should be recognized that this invention incorporates a greater number of baffle paths than shown in FIG. 5.
FIG. 6 is a bottom view of the embodiment of FIG. 2. Therein is shown the longitudinal split edges 22 and 23 spread apart upon being positioned into aperture 17. The split edges such as 22, 23 and 22a and 23a abut the inner periphery of the aperture 17 to form the seals notwithstanding the relatively loose tolerance maintained in drilling the apertures and in extruding the baffle blades.
In practice, a baffle blade 19 is pushed into the baffle aperture 17 with the broadside of its body 21 facing the aperture 16, so that the liquid is caused to flow around the baffle blade and either through the pointed portion of the drilled hole 34 or through a notch such as notch 26 on the inner side of the main body 21. The spread longitudinal edges 22 and 23 contact the walls of the aperture and form the required seal.
The positioning of the blade is observable by the user since the plug is not an integral part of the blade. Finally, the plug is put into place forcing the blade down even further to collapse the bottom outer parts of the flexible longitudinal split ends thereby properly positioning and locking the baffle blade into place.
Those who are skilled in the art will perceive other embodiments and modifications which may be made. Therefore, the claims are to be construed to cover all equivalent structures which fall within the true spirit and scope of the invention.
1. In a mold having apertures therein, bafile blade arrangements for use in lengthening heat exchange fluid pathways through said apertures,
said baffle blade arrangements comprising a baffle blade having a main body section,
flexible means integral to said main body section,
said baffle blade arrangements having a cross sectional transverse dimension slightly larger than the diameter of said apertures to place said baffle blade arrangements in compression when in the apertures for assuring that said baffle blade properly seats against the inner periphery of the apertures, and
means independent and separate from said baffle blade used for sealing the apertures with said baffle blade arrangements therein.
2. The baffle blade arrangement of claim 1 wherein said means integral to said main body section comprises longitudinal split edges on said main body sectron,
whereby when said baffle blade is pressed into the aperture the longitudinal split edges spread and there is a double contiguous wall against'said inner periphery of the aperture on each side of said blade.
3. The baffle blade arrangement of claim 2 wherein said longitudinal splitedges have a cross-sectional V- like form on each side of said main body.
4. The baffle blade arrangement of claim 3 wherein said special aperture terminates in internal pipe threads at the outer end thereof, and
wherein said means independent and separate from said baffle blade comprises threaded pipe lugs for threading into the aperture to seal the aperture with a baffle blade therein.
5. The baffle blade arrangement of claim 4 wherein said main body section is notched at the inner end thereof to facilitate the passage of the heat exchange liquid in the path that extends from the inlet to the aperture around the baffle blade to the outlet from the special aperture.
6. The baffle blade arrangement of claim 5 wherein the inner end of the aperture has a point-like shape, and
wherein the length of said baffle blade and said pipe plug combined is slightly longer than said aperture,
whereby when said pipe plug is threaded into the threaded portion of the aperture the baffle blade is forced down to collapse the split edges at the inner end of said blade. I
7. The baffle blade arrangement of claim 1 wherein said baffle blade causes the heat exchange liquid in the aperture to flow inward and outward more than once.
8. The bafile blade arrangement of claim 1 wherein said blade comprises a plurality of sections,
a first section of said blade causing the heat exchange liquid from the inlet to flow inward and around the inner end of said first section of said blade,
a second section of said blade causing said liquid to flow toward and around the outer end of said second section,
a third section of said blade causing said liquid to flow toward and around the inner end of said third section, and
a fourth section of said blade causing the liquid to flow out of said outlet.
9. In a mold having apertures therein, baffle blade arrangements for use in lengthening heat exchange fluid pathways through the apertures,
said baffle blade arrangements comprising a baffle blade having a main body section,
flexible means integral to said main body section for assuring that said baffle blade properly seats against the inner periphery of the apertures,
said baffle blade arrangements produced from extruded material cut to the desired length, and
means independent and separate from said baffle blade arrangements used for sealing the apertures with said baffle blade arrangements therein.
10. The baffle blade arrangement of claim 9 wherein said means integral to said main body section comprises longitudinal split edges on said main body sectron,
whereby when said baffle blade is pressed into said special aperture the longitudinal split edges spread and there is a double contiguous wall against said inner periphery of the aperture on each side of said blade.