Abstract: Non-stick mold, tool or apparatus is used to convert a liquid or semi-solid material to an end product after the application of a predetermined temperature for a predetermined time. The non-stick mold, tool or apparatus includes a planar portion having at least one cavity. The cavity defined by a side wall that extends downwardly from the planar portion to a closed end. The non-stick mold, tool or apparatus is made from a blend of a fluoropolymer component and a food grade silicon rubber component.

Abstract: A method of patterning metallic building elements, and also to a metallic building element, where the measuring accuracy achieved can lie in the sub-micrometer range is disclored. Starting from a silicon master or original that can be etched to sub-micrometer precision and then plated with a metal, such as nickel, on the silicon surface, there can be produced a nickel shim where precision and surface fineness can lie in the sub-micrometer range. Subsequent to removal of the silicon master, a photo-sensitive material can be used in liquid form or in film form to create mould cavities that reach down to the nickel shim. These cavities can then be metal-plated to provide a building element of higher precision in three dimensions.

Abstract: An automatic ice maker of the open-cell type including a box-type housing, a plurality of spaced ice making cell casings arranged on a horizontal plane in an upper portion of the housing and opened downward, a cooling pipe mounted on the cell casings to be supplied with refrigerant from a freezing circuit, and a sprinkler mounted within a bottom portion of the housing and placed under the cell casings to spout ice making water into the respective cell casings, wherein a base plate is mounted within the upper portion of the housing to form an ice making chamber, and wherein the ice making cell casings are secured to a bottom surface of the base plate, while the cooling pipe is mounted on the base plate at positions located above the cell casings and welded to an upper surface of the base plate.

Abstract: An article for holding freezable substances includes an individual disposable package for holding the frozen substance and a container therefore. The package is comprised of a bottom portion and a top portion. The frozen substance is placed in the bottom portion and the top portion is placed over the bottom portion to seal the package and prevent spillage of the freezable substance prior to its freezing. The package has a maximum inner width Wm, with Wm being less than or equal to 0.875 inches (22.23 mm). The width Wm is chosen so that a long, cylindrical ice cube is formed by the package. The ice cube so formed fits easily into original containers of beverages, such as soda cans and bottles, so that the beverages are cooled in their original containers.

Abstract: A freezer tray unit that houses removable inserts with various cavity shapes. This unit can be used to make ice in an unlimited number of shapes, by simply changing the inserts. This unit is made up of several kit contents. The quantities required for one kit are the body (1), slotted rod (1), bottom tray (1), releasers (8), and inserts (8). The unit utilizes two mechanisms for ice removal. One mechanism removes ice from individual inserts. Features responsible for this mechanism are the insert guard, slotted rod, releaser, and bottom tray. Another mechanism removes ice from all the inserts simultaneously. The ice removal features utilized in this mechanism are the insert guard, ice guard, slotted rod, and releaser. The inserts can be utilized independently in refrigerators for effective space management. Also, the inserts may be utilized for making baked products in ovens.

Abstract: An apparatus for preparing a plastic eyeglass lens includes a coating unit and a lens curing unit. The apparatus is preferably configured to allow the operation of both the coating unit and the lens curing unit. The apparatus may also include a post-cure unit and a controller. The controller is configured to control the operation of the coating unit, the lens curing unit and the post-cure unit. The lens forming unit may include an LCD filter disposed between activating light sources and a mold assembly. The mold assembly preferably includes two mold members held together by a gasket. The gasket preferably includes four protrusions spaced at 90 degree intervals about the gasket. A lens forming composition may include a first photochromic compound, a second photochromic compound and a light effector. The light effector may alter the color of a lens when exposed to photochromic activating light, when compared to a lens formed from a lens forming composition which does not include a light effector.

Abstract: A bag useful for forming ice cubes or the like has a pouch-like fill chamber which may extend across the whole of the width of the bag. The fill chamber has an outlet opening connecting to the interior of the bags which comprises at least two passageways in parallel relationship. An internal seal is provided to isolate the fill chamber from the interior of the bag. The seal may comprise a zip type fastener, or a simple flap valve disposed in each of the passageways. The arrangement facilitates the handling of the bags to permit larger bags that may be filled more rapidly and with little or no air trapped within the bag, in comparison to other known bags.

Abstract: Hybrid molds for molding a multiplicity of solder balls for use in a molten solder screening process and methods for preparing such molds are disclosed. A method for forming the multiplicity of cavities in a pyramidal shape by anisotropically etching a crystalline silicon substrate along a specific crystallographic plane is utilized to form a crystalline silicon face plate used in the present invention hybrid mold. In a preferred embodiment, a silicon face plate is bonded to a borosilicate glass backing plate by adhesive means in a method that ensures coplanarity is achieved between the top surfaces of the silicon face plate and the glass backing plate. In an alternate embodiment, an additional glass frame is used for bonding a silicon face plate to a glass backing plate, again with ensured coplanarity between the top surfaces of the silicon face plate and the glass frame. In a second alternate embodiment, a silicon face plate is encased in an extender material which may be borosilicate glass or a polymer.

Abstract: An apparatus and method for custom blending and fabricating lipstick to the specific demands of individual customers. The present invention provides a kit which enables a user to blend various pigments to arrive at a very specific shade, and then blend the desired shade with a specific base to result in a desired consistency of lipstick, and which also allows the blended bases and pigments to be heated to a liquefied form and poured into a mold for hardening. Upon cooling and hardening, a conventional lipstick case can be attached to the lipstick for removal from the mold and use by the customer. The present invention therefore not only allows a user to quickly attain the specific shade and consistency of lipstick desired, but also eliminates the time consuming and unsatisfactory process of visiting multiple stores having expansive inventories of variously shaded and textured lipsticks.

Abstract: Hybrid molds for molding a multiplicity of solder balls for use in a molten solder screening process and methods for preparing such molds are disclosed. A method for forming the multiplicity of cavities in a pyramidal shape by anisotropically etching a crystalline silicon substrate along a specific crystallographic plane is utilized to form a crystalline silicon face plate used in the present invention hybrid mold. In a preferred embodiment, a silicon face plate is bonded to a borosilicate glass backing plate by adhesive means in a method that ensures coplanarity is achieved between the top surfaces of the silicon face plate and the glass backing plate. In an alternate embodiment, an additional glass frame is used for bonding a silicon face plate to a glass backing plate, again with ensured coplanarity between the top surfaces of the silicon face plate and the glass frame. In a second alternate embodiment, a silicon face plate is encased in an extender material which may be borosilicate glass or a polymer.

Abstract: An article for forming a freezable substance includes a body having at least one cavity. The cavity has an open top, an open bottom and side walls therebetween. The top has a maximum width Wm, with Wm being less than or equal to 0.875 inches (22.23 mm). The width Wm is chosen so that a long, cylindrical ice cube is formed by the cavity. The ice cube so formed fits easily into original containers of beverages, such as soda cans and bottles, so that the beverages are cooled in their original containers.

Abstract: The pulp mold of the invention comprises a plurality of successive pulp mold units. Each unit comprises a plurality of higher and lower surfaces such that the pulp mold has a plurality of corrugated surfaces to provide a plurality of cushions and to simulate the deformation and spring recovery effect for performing positioning and cushioning. The pulp mold of the invention can adjust the number of pulp mold unit according to the weight and size of the article. The molding unit means of the invention can be constructed to be suitable for various articles. When the articles are no longer manufactured, the molding unit means can be re-constructed to be suitably used on other products.

Abstract: An ice tray includes mold cells each having an open top and closed bottom. The bottom is air permeable for venting released air during formation of ice cubes therein. And, external sides of the ice tray may be thermally insulated for enhancing directional solidification of the ice cubes.

Abstract: A mold box is flexibly mounted to a product forming machine having upper and lower vertically displaceable beams. A feed drawer dispenses concrete material into the mold box while a vibration system vertically vibrates the mold box while dampening horizontal vibration. The vibration system is driven by a single drive shaft that actuates first and second vibrator rods while at the same rotating a counter-weight in a counter-rotating direction. A set of alignment brackets lock the mold box into a predetermined aligned relationship while being mounted in the product forming machine. The bottom side of each mold box is mounted to the product forming machine in the same relative position to reduce machine readjustments. A set of telescoping legs hold the feed drawer assembly variable distances above the mold box. A unitized pallet feeder quickly moves pallets one at a time from an “on-deck” position to a “receiving” position underneath the mold box.

Abstract: An article for forming a freezable substance includes a body having at least one cavity. The cavity has an open top, an open bottom and side walls therebetween. The top has a maximum width Wm, with Wm being less than or equal to 0.875 inches (22.23 mm). The width Wm is chosen so that a long, cylindrical ice cube is formed by the cavity. The ice cube so formed fits easily into original containers of beverages, such as soda cans and bottles, so that the beverages are cooled in their original containers.

Abstract: An ice cube bag comprises two sheet-shaped foil layers (12, 14; 12′, 14′) defining an outer periphery. A peripheral joint (20, 21, 21a, 21b) extends along the major part of the outer periphery of the foil layers, with the exception of a peripheral area constituting an inlet aperture of the bag (10). Their peripheral joint joins the foil layers together defining an inner chamber which is divided into several ice cube compartments defined by separate joints (22, 23, 24, 25, 29) of the foil layers. An inlet channel extends from the inlet aperture to the inner chamber of the bag hereby allowing admission from the surroundings to the inner chamber of the bag through the inlet channel.

Abstract: An article for forming a freezable substance includes a body having at least one cavity. The cavity has an open top, an open bottom and side walls therebetween. The top has a maximum width Wm, with Wm being less than or equal to 0.875 inches (22.23 mm). The width Wm is chosen so that a long, cylindrical ice cube is formed by the cavity. The ice cube so formed fits easily into original containers of beverages, such as soda cans and bottles, so that the beverages are cooled in their original containers.

Abstract: A baking pan for baking wedding cakes has the overall form of a cupcake pan, except that each baking unit has multiple tiers. In one embodiment, the baking pan has six baking units, each of which has three cylindrical tiers with steadily decreasing diameters to define the shape of a three-tier wedding cake. Thus, multi-tier wedding cakes are baked in one piece.

Abstract: A mold for producing a masonry unit with a roughened texture side surface having a plurality of side walls defining a mold cavity open at its top and bottom, adapted to receive masonry fill material by way of its open top, and to discharge molded fill material in the form of a block of predetermined height by way of its open bottom; and a wedge-shaped lower lip located along the lower edge of at least one of the side walls, and extending into the mold cavity, the lower lip having grooves formed therein which are oriented at an oblique angle to the general direction of movement of concrete fill material through the mold cavity.

Abstract: A covered ice cube tray is provided for making, storing, and dispensing ice cubes. The cover is slidably mounted upon the tray and includes at least one leading edge that is shaped so that, as the cover is moved in relation to the tray, ice cubes are uncovered and may be dispensed one-at-a-time.

Abstract: An ice cube storage and dispensing unit having an ice cube tray tray with a plurality of ice cube compartments and a plurality of slits along one of the longitudinal edges. There is a cover is removably secured to the ice cube tray which creates a closed space above the ice cube tray. The cover has an open end. There are a plurality of latches located along the bottom edge of one of the longitudinal side walls of the cover. The latches engage the slits in the ice cube tray to pivotally attach the cover to the ice cube tray. There is a flange located around the bottom edge of the other longitudinal side wall that releasably engages a groove in the other longitudinal edge of the ice cube tray to releasably lock the cover over the ice cube tray. There is a flap in the top surface of the cover near the free end to create a slot and a door at the open end of the cover to seal the space above the ice cube tray. The door is pivotally attached to one of the side walls and has a panel inserted into the slot.

Abstract: A method for forming solder bumps on an electronic structure including the steps of first providing a mold made by a sheet of a mold material having a thickness greater than that of the solder bumps to be formed, the mold material has sufficient optical transparency so as to allow the inspection of a solder material subsequently filled into the mold cavities that are formed in the mold material, and a coefficient of thermal expansion that is substantially similar to the substrate which the mold will be mated to, forming a multiplicity of mold cavities in the sheet of mold material, filling the multiplicity of mold cavities with a solder material, cooling the mold to a temperature that is sufficient to solidify the solder material in the multiplicity of mold cavities, positioning the mold intimately with the electronic structure such that the cavities facing the structure, and heating the mold and the structure together to a temperature sufficiently high such that the solder material transfers onto the electro

Abstract: A voltage is applied to a feeder plate (29) from a power source section (2) including an alternating power source for dielectric heating, whereby an electric field in a direction crossing a direction in which a mold (8) is moved is applied to an incoming plate (28) which is not in contact with the feeder plate (29), so that molded object materials (9) are heated and expanded. By doing so, arc discharge caused by contact of the mold with an electrode is prevented from occurring during the heating and molding of a biodegradable molded object by dielectric heating.

Abstract: A unitary concrete product mold formed from a central member having an array of product-shaping molds bounded by side and end portions. Support rails mounted on the bottom surface of the central member limit deflection of the central portion of the central member, improving product quality and reducing mold wear.

Abstract: A molding apparatus has a fixed mold part having a pair of flat side faces and formed on each face with a plurality of laterally open half cavities and respective movable mold parts each having a side face juxtaposed with a respective fixed-part side face and displaceable transversely into and out of a molding position with the movable-part side face flatly engaging the respective fixed-part side face of the stationary mold part. Each movable mold part is formed with a plurality of half cavities forming full mold cavities with the half cavities of the respective fixed-part side face in the molding position. Each movable-part half cavity is formed with at least two inwardly open pockets, one of the pockets of each movable-part half cavity being open at the respective movable-part side face and being transversely closed by the respective fixed-part side face.

Abstract: An ice bar tray for making various lengths of ice bars for use in different types and sizes of water bags. Each ice bar has a round cross section for ease in inserting into circular water fill openings in a water bag. The ice bar tray includes at least one elongated bar cylinder with a tray handle on each end. The bar cylinder has an elongated cylinder opening in a top of the cylinder for receiving water into a water channel. The water channel has a circular cross section. The water channel is disposed along a length of the elongated cylinder. When the water channel is filled with water and the water frozen, a round ice bar is formed therein. By flexing the ice bar tray, which is made of a flexible PVC plastic material and the like, the frozen ice bar is released outwardly from the water channel and through the cylinder opening. The ice bar is then inserted into the water fill opening in the water bag. The ice bar tray also includes a tray slide with at least one cylinder divider.

Abstract: An apparatus and method for custom blending and fabricating lipstick to the specific demands of individual customers. The present invention provides a kit which enables a user to blend various pigments to arrive at a very specific shade, and then blend the desired shade with a specific base to result in a desired consistency of lipstick, and which also allows the blended bases and pigments to be heated to a liquefied form and poured into a mold for hardening. Upon cooling and hardening, a conventional lipstick case can be attached to the lipstick for removal from the mold and use by the customer. The present invention therefore not only allows a user to quickly attain the specific shade and consistency of lipstick desired, but also eliminates the time consuming and unsatisfactory process of visiting multiple stores having expansive inventories of variously shaded and textured lipsticks.

Abstract: A method is described for forming solder mounds for attachment to electronic devices. The solder mounds are preferably in the form of columns and comprise a first solder portion and a second solder portion with the two solder portions having different melting points. The solder columns are preferably formed using an injection molding device. The method is directed to the use of a single column mold to form the multi-solder column. In one embodiment, deformable material is used to partially block a portion of the through opening of the mold during a first solder injection process. The deformable material is then removed and the remainder of the through openings of the mold filled with a second molten solder. The multi-solder column is then electrically connected to a substrate by reflowing.

Abstract: A adjustable mold box assembly for forming molded concrete products includes a pair of opposed substantially parallel end plates joined at both ends by a pair of opposed substantially parallel mounting brackets. A selected plurality of partition plates extend between the end plates to define a plurality of cavities for forming molded products in accordance with the number and dimension of molded products desired. A slot is formed along the inside of each end plate substantially along the length thereof. Tabs which extend from opposing ends of each partition plate include a stud transversely mounted on the end plate using ring nuts. The opposing tabs and studs of each end plate are received in opposing end plate slots. End liners are bolted to the inside surface of each end plate over the studs on each side of each partition plate with the ring nuts bearing against the surface of the end liner.

Abstract: A ice puck mold and storage system is provided including at least one hockey puck mold having a circular bottom face and a cylindrical periphery integrally coupled thereto and extending upwardly therefrom for defining an upper peripheral edge, an interior space, and an open top.

Abstract: A first ice making bag (110) comprises a first envelope (112) which comprises a first envelope top (112T) and a first envelope bottom (112B). The first ice making bag (110) further comprises a first binding (114) which comprises a first peripheral binding (114A). A first left peripheral opening binding (114AL), and a first right peripheral opening binding (114AR). The first left peripheral opening binding (114AL) and the first right peripheral opening binding (114AR) form a gap therebetween. The first binding (114) functions to form a pocket between the first envelope top (112T) and the first envelope bottom (112B). The first ice making bag (110) further comprises at least one first opening binding (114B) forming an air channel between the first left peripheral opening binding (114AL) or the first right peripheral opening binding (114AR) and the at least one first opening binding (114B).

Abstract: The two sides of a multiple cavity mold having electroformed mold cavities for molding intraocular lenses with integral haptics are made by a preferred electroforming procedure involving the use of either a single primary master having a single cavity corresponding to the portion of the lens at either side of its median plane transverse to its optic axis if the lens to be molded is symetrical about both this transverse median plane and its longitudinal median plane containing the optic axis, or a pair of primary masters having single cavities, respectively, corresponding to the portions of each lens at opposite sides of its transverse median plane if the lens is unsymmetrical about either plane.

Abstract: A method for forming thin green ceramic igniter shapes having a thickness characterized by a tolerance of no more than about +/-0.001 inch includes providing an apparatus having a porous mold having a well which defines a pair of opposing porous walls, and a plurality of vertical dividers positioned in the well in substantially parallel, substantially spaced relation where each divider contacting each opposing wall to define a plurality of compartments. A ceramic slip formed from a ceramic powder and a liquid carrier is poured into the compartments of the apparatus, dewatered through the opposing porous walls to form a plurality of green ceramic igniter shapes. The plurality of green ceramic igniter shapes are removed from the plurality of compartments.

Abstract: The invention is an improvement to mold frames having replaceable half-molds for forming golf balls. The invention is directed to dividing the flow path through the mold for the thermal medium into a plurality (2 to the number of cavity rows) of parallel flow paths, i.e., water entering the mold flows through only one row of half-molds.

Abstract: A process for forming a steel shuttering frame for a building with a reinforced concrete structure. The process includes the following steps: (1) setting up a supporting stand for the shuttering frame, (2) mounting shutter plates for forming a floor portion of the building on a top of the supporting stand, (3) mounting inside shutter plates for forming inner surfaces of side walls of the building on sides of the supporting stand, (4) mounting outside shutter plates for forming outer surfaces of the side walls of the building around the inside shutter plates, and (5) fixedly connecting the inside and outside shutter plates together while keeping them separated from each other a predetermined distance equal to the thickness of the side walls of the building.

Abstract: A baking utensil so shaped as to mold within bread dough baked upon it one or more buns, each with a recess to retain a weiner, bratwurst, frankfurter, processed meat link, hamburger or other cooked meat product.

Abstract: A mold for producing molded concrete items is disclosed. The mold includes a mold frame; a plurality of spaced apart mold cavities contained within the mold frame for receiving concrete and forming of individual concrete items upon curing of the concrete received therein; and an elastic casting material positioning the plurality of spaced apart mold cavities within the mold frame while permitting movement of the mold cavities within the mold space with the elastic casting material contacting side walls of the mold and filling spaces between the spaced apart mold cavities and contacting outer walls of the spaced apart mold cavities.

Abstract: A muffin tray made from modified crystalline polyethylene terephthalate has a plurality of baking wells with heat-transfer inhibiting bottoms, and protruding circumferential ridges to accommodate differential thermal expansion while limiting related distortion. The muffin tray is used in a baking process having a baking step using a spiral oven with a water bath therein. Hot air is directed into close surface contact with the water pool and then into cross-flow relationship with the muffin trays to effect baking of muffin batter.

Abstract: A molded proofer tray (10) for use in commercial bakeries, includes threaded inserts (28) molded directly into the outer end (14) walls for removably receiving mounting pins (30) to facilitate repair if damaged. A female embodiment (40) is also provided.

Abstract: A mold box assembly for forming molded concrete products includes a pair of opposed substantially parallel end plates joined at both ends by a pair of opposed substantially parallel mounting brackets. A plurality of partition plates extend between the end plates to define a plurality of substantially identical cavities for forming molded products. A slot is formed along the inside of each end plate substantially along the length thereof. Tabs which extend from opposing ends of each partition plate include a stud transversely mounted on the end plate using ring nuts. The opposing tabs and studs of each end plate are received in opposing end plate slots. End liners are bolted to the inside surface of each end plate over the studs on each side of each partition plate with the ring nuts bearing against the surface of the end liner.

Abstract: A freezing mould bag for ices is formed from two plastic foils, and has a segmented inlet channel, two closure valve flaps extending within the interior of the bag, and a constriction which provides a venturi effect closing the bag at the constriction.

Abstract: An apparatus and method for connected forming and controlled stacking of material having a form (12). The form (12) includes at least two molds (14) connected to each other by a web (16). The introduction of material into the form (12) results in the material generally assuming the shape of the molds (14) and the web (16). As a result, when the material is pressed out of the molds (14), the material is held together in the preselected position by the resultant web (16). This enables the stacking of material on top of each other in a controlled and certain manner since the forms pressed from the molds (14) will retain their chosen spaced apart distance and fall consistently and uniformally on top of each other until such time as the desired height of stacked material is achieved.

Abstract: A round , prestressed concrete pile having front and back flat portions and a method and apparatus for manufacturing the piles. The apparatus comprises essentially a plurality of horizontally placed piling molds and a concrete feeder and spreader. The concrete feeder and spreader are pulled across the pile molds by a spreader driver attached to a first end of the pile molds and the piles are removed from the pile molds by a cable tensioner and piling extractor attached to a second end of the pile molds. The piles are prestressed with flexible cable, wrapped with concertina wire, and embedded in concrete poured into the pile molds. The piles may be cast in different lengths by utilizing a bucket mold on the lower end.

Abstract: Waste products which are to be disposed of by burial, are mixed with a hardening substance in bags which are wrapped around circular or approximately circular frames. The circular shape enables efficient mixing. The bagged frames are placed in a rectangular mould and the bags then filled and the contents mixed by stirring; the wrappings are released and the mixes settle into the shape of the rectangular interior of the mold and fill it, thus adopting the most efficient storage shape.

Abstract: A device for forming cakes and the like into three-dimensional structures, including a geometric grid of cutter blades arranged with a particular desired contour along their outer edges, wherein the cutter blades are formed into two identical half sections. The half sections may then be embedded into a pre-cooked cake to form the cake into slices confined within the half sections, and the half sections may then be affixed together and frosting applied to the exterior surface of the cake.

Abstract: The closure lid is designed as mold on the container body. The volume enclosed by the closure lid and the container body equals at least approximately the volume of the product filled into the container. The edible good is placed in a flowable state into the container body. Thereafter the closure lid which is recessed relative to the upper edge of the container is placed onto the container body and molds the surface of the filled in edible good to attain a predetermined structure. Upon a cooling the edible good attains a solid state in such a manner, that its surface keeps permanently the shape produced by the closure lid.

Abstract: An indented, invertable food pan may be used to produce combinable halves of a sturdy composite food product. The food pan has an open end, a closed end and an end wall. At the closed end, the end wall has at least one indentation partially or completely surrounding a raised center. The indented end wall divides the pan into two complementary shaped hollow volumes, with each of the volumes adapted to be filled with one of the two food compositions. Removing the food compositions from the hollow volumes produces two complementary food shapes which are then combined to produce a first composite half of the final composite food product. A second identical half formed in the same manner is inverted and stacked onto the first half to produce the final composite food product. In one embodiment, the end wall has a plurality of indentations to define a plurality of hollow volumes at the closed end. Each hollow volume is used to produce a separately concealed filling, with one filling for each serving portion.

Abstract: An ice cube tray consisting of an inner tray divided lengthwise and breadthwise into a plurality of pockets with open tops, and an outer tray divided into a configuration that fits the shape of the inner tray forming a space between the outer bottom of the inner tray and the inner bottom of the outer tray, with openings provided on the bottom of the inner tray so as to make transparent ice in the pockets, and additionally providing slightly curved protruding points on the bottom of the outer tray to allow for expansion.

Abstract: A pan used to contain baked goods during a commercial baking process having a circumferential edge flange which is along a same horizontal plane as molds which make up the bottom of the pan, thereby providing added support to the pan when in use during the baking process and while it is stacked on top of other pans for storage purposes. The pan also having a circumferential corrugation feature which increases the ability of the edge flange to withstand shearing and bending stress.

Abstract: The mold is comprised of a bottom (4) wherein there are provided grooves (8) extending transversely between containment sidewalls (6); said sidewalls (6) have windows (14) which are aligned with the grooves (8) which preferably are delimited by the faces (10) of fillets (12) arranged in parallel, facing each other and fixed to the bottom (4) of the mold.