KR20020026552A - Heat Treatment and Sand Removal for Castings - Google Patents

Abstract

Systems and methods are provided for heat treating castings 13, 53 and removing core 54. Castings 13, 53 are initially positioned at indexed positions where the x, y, z coordinates are known. The castings 13, 53 each comprise a series of nozzle stations each having a series of nozzles 42, 64, 64 ′ mounted at a given position corresponding to a known indexed position of the casting passing through the nozzle stations 41, 63 ( 41, 63). The nozzles 42, 64, 64 ′ apply a heating fluid to the castings 13, 53 to heat the castings 13, 53 and remove the sand core 54 from the castings 13, 53.

Description

Heat Treatment and Sand Removal for Castings

Conventional casting processes for forming metal castings are cast iron flask-type molds or sand molds, also known as dies, which have external features of the desired casting, such as, for example, a cylinder head formed on the inner face. Adopt. A sand core composed of sand and a suitable binder material and forming the internal features of the casting is located in the die. Sand cores are generally used to make contours and internal features in metal castings, and removal and regeneration of the sand material of the cores from the castings is essential after the casting process is complete. Depending on the application, when binders for sand cores and / or sand molds are used, the binder may comprise a phenolic resin binder, a phenol urethane “cold box” binder, or other suitable organic binder material. The die is then filled with a molten metal alloy. Once the alloy is solidified, the casting is generally removed from the die and then transferred to a treatment furnace for heat treatment, regeneration and aging of sand from the sand core. Heat treatment and aging is a process in which metal alloys are adjusted to provide different physical properties suitable for many different applications.

According to some prior art, once the casting has been formed, significantly different steps generally have to be performed to heat the metal casting and to recover sufficiently clean sand from the sand core. The first step separates a part of the sand core from the casting. The sand core is generally separated from the casting by one means or a combination of means. For example, sand may be removed from the casting or the casting may be physically shaken or vibrated to break the sand core and remove the sand. Once the sand is removed from the casting, the heat treatment and aging of the casting is generally performed in successive steps. If it is desirable to strengthen or cure the casting, it is generally heat treated. An additional step consists in purifying the sand separated from the casting. The purification process is generally carried out by one means or a combination of means. Such processes may include the combustion of the sand-covering binder, the sanding up of sand, and the passage of a portion of the sand through a screen. Thus, some sand may be subjected to regeneration processes again until sufficiently clean sand is regenerated.

Therefore, there is a need in the industry to improve the heat treatment process of castings and the process of reclaiming sand core materials, and more efficient methods and related methods that enable more efficient heat treatment, removal of sand cores and regeneration of sufficiently pure sand from sand cores. Devices continue to be required.

The present invention relates to a metallurgical casting process, and more particularly, to a method and apparatus for removing sand cores from a casting and for heat treatment of the casting.

1 is a schematic diagram of a first embodiment of the present invention.

Figure 2 is a side front view illustrating the injection of molten metal into the die.

3 is a perspective view showing the positioning of the casting in the saddle;

4 is a schematic diagram of another embodiment of the present invention for in-die heat treatment in conjunction with a sand core removal process.

5A and 5B are side elevation views showing the movement of the air nozzle to various application locations around the die for in-die heat treatment.

FIG. 6 is a side front view schematically illustrating an alternative embodiment of a heating chamber for in-die heat treatment of a casting. FIG.

FIG. 7 is a side front view schematically illustrating another alternative embodiment of a heating chamber for in-die heat treatment of a casting. FIG.

8A and 8B are side elevation views schematically illustrating another alternative embodiment of a heating chamber for in-die heat treatment of a casting.

Briefly described, the present invention includes systems and methods for heat treatment castings, such as for use in metallurgical plants, and systems and methods for removing sand cores used during the casting process. The present invention includes several embodiments for the effective removal and regeneration of sand in a sand core using high pressure fluid media and for in-die heat treatment of castings.

In one embodiment of the present invention for removal of sand cores and heat treatment of castings, when a casting is formed in a die, molten metal is poured into a die that is generally preheated to maintain the temperature of the metal close to the heat treatment temperature. Lose. The castings are then removed from the die and placed at predetermined positions on saddles with known x, y and z axes and coordinates, respectively. Each bird is formed to receive the casting at a fixed orientation or location, where the x, y and z coordinates of the casting are generally located at a known or indexed location or orientation, such that the core formed by the sand core The holes are known, oriented and aligned at the indexed position. The birds further comprise a positioning device to assist and guide the casting at the desired, known and indexed position.

Each bird with a casting located therein is moved through a chamber or heat treatment furnace of a heat treatment station for heat treatment and core removal, and potentially for regeneration of the sand core. While passing through a heat treatment station for heat treatment, a series of nozzles in which the x, y and z coordinates are fixed and placed in alignment with the casting's position is used to control the flow of a high pressure heated fluid medium such as air, water or heating oil. Guide over and into the casting. As the sand core breaks down in the heat treatment station, the fluid flow tends to escape and help remove the sand of the sand core from the internal cavity of the casting. In general, the nozzles are arranged in a series of nozzle stations located continuously through the heat treatment chamber, and the nozzles of each nozzle station are oriented in a predetermined alignment corresponding to the known position of the core hole of the casting, and each nozzle assembly Is remotely controlled via a control system or station.

In another embodiment of the invention, the casting is left in the die for heat treatment within the die. The die is generally preheated before the molten metal of the casting is injected into the die to keep it close to the heat treatment temperature for the casting, thereby partially heat treating the casting in the die during solidifying the casting. As such, the die with the casting therein is generally positioned in an indexed orientation or position with known x, y and z coordinates for heat treatment of the internal casting and removal of the sand core.

For heat treatment and removal and reclamation of the sand core of the casting, the die and casting are generally passed through a heat treatment furnace at a heat treatment station. The heat treatment station further includes a plurality of nozzle stations each having a series of nozzles oriented and positioned in a predetermined manner corresponding to the die and casting in a known position for applying a high pressure fluid. The nozzle station moves along a predetermined passageway around the die to various application locations corresponding to the position or orientation of the die entry openings or holes in the die for access to the casting to release the sand core from the casting. It also includes. Optionally, the heat treatment station also includes an optional energy source, such as an electromagnetic induction or radiant energy source, or an oxygen chamber for energizing the die or mold pack to raise the temperature for heat treatment of the casting therebetween. . As a result, the casting is removed from the die, and then passed through a continuous core removal station or process to further remove and potentially reclaim sand cores from the casting.

In another embodiment, the die is preheated to a predetermined temperature. Then, when molten metal is injected into the die, the die is continuously heated to heat-treat the casting as the casting solidifies without removal of the casting from the die. The die is then conveyed to a quench station for quenching the casting and removing sand cores from the die. In this embodiment, the die is generally known at or adjacent to the infusion station and is maintained at a fixed position or orientation. The die is heated by the application of heating fluid from a series of nozzles positioned relative to the die and aligned with the die entry opening. The nozzle is further moved continuously around the dies between a series of nozzle positions set according to the position or orientation of the die to heat the die to heat treat the casting within the die.

Various objects, features and advantages of the present invention will become apparent upon reading and understanding the present specification in conjunction with the accompanying drawings.

Referring now to the drawings in greater detail, the same reference numerals represent the same parts throughout the several views, and FIG. 1 generally illustrates a metallurgical casting process 10. Casting processes are well known to those skilled in the art, and a brief description of conventional casting processes is provided for reference.

As shown in Figs. 1 and 2, in accordance with the present invention, the molten metal or metal alloy M is injected or casting station to form a casting 13 (see Fig. 3) such as a cylinder head or an automobile engine block. It is injected into die 11 of 12. In general, the casting core is received and positioned to create a hollow and / or casting detail or core print in the casting formed in each die. Each die 11 is generally a flask-type mold and has a cast iron or other material having a clam-shell design for easy opening and removal of the casting from the die as is known in the art. It may be formed of the same metal. The die is also a green sand mold formed from a sand material mixed with a binder, such as a phenolic resin or other suitable organic binder material, as is known in the art. Likewise, foundry cores generally comprise sand cores formed of suitable binder and sand materials, such as phenolic resins, phenol urethane “cold box” binders or other suitable organic binder materials, as is known in the art.

As shown in FIG. 3, each die 11 generally has a series of sidewalls 14, top walls 16 and bottom walls, which form an internal cavity 18 in which molten metal M is accommodated. 17). The inner cavity 18 is generally formed in embossed form to form the internal features of the casting 13 formed in the die to form the shape or shape of the finished casting. An injection opening 19 is generally formed in the upper wall 16 of each die, such that the molten metal M is injected or introduced into the die as shown in FIGS. 1 and 2. Communicating with The resulting casting has the features of the inner cavity of the die, and additional core holes or entry openings 21 are also formed inside where the sand core is positioned in the die.

Heating elements such as a heated air blower or other suitable gas or electric flame heater mechanism 22 are also generally provided adjacent to the injection station 12 to preheat the die 11. Optionally, the die is provided with a heating source or heating element for heating the die. For example, the die includes a cavity adjacent to the casting in which a heating medium, such as heating oil, is received to heat the die. Generally, the die is preheated to the desired temperature depending on the metal or alloy used to form the casting. For example, in aluminum, the die is preheated in the range of approximately 400 to 600 ° C. The variable preheat temperatures required to preheat the various metal alloys or other metals to form the casting are well known to those skilled in the art and include a wide range of temperatures of approximately 400 to 600 ° C. The preheating of the die allows the casting metal to be maintained at or near the heat treatment temperature to minimize heat loss when molten metal is injected and solidified in the die, after which the die is transferred to the next process station for heat treatment of the casting. Is moved.

As shown in Figure 1, once molten metal or metal alloy has been injected into the die and at least partially solidified in the mold, the die and casting are removed from the injection station 12 by the die transfer mechanism 25 and loaded. ) Is moved to station 26. Die movement mechanisms include die movement robots (not shown), winches or other types of movement mechanisms known in the art for moving a die from an injection station to a loading station. In the first embodiment of the invention, after the molten metal M solidifies in the die to form a casting, the casting 13 (see FIG. 3) is loaded by the robot arm or similar mechanism to the loading station 26 (FIG. 1), and the x, y, z coordinates are located in the saddle 27 at a known, indexed position. As a result, the core hole 21 (see FIG. 3) of the casting is likewise oriented or aligned to a known position for removal of the sand core from the casting.

As shown in Figure 3, each bird is a basket or carrier generally formed of a metallic material, the basket or carrier being a core hole or entry opening in which the casting 13 is received and exposed. It has a base 28 and a series of side walls 29 for defining an open casting chamber or receptacle 31 having a. The casting is generally fixed in a known indexed or mating orientation or position when located within the receptacle 31 of the saddle 27. In addition, as shown in FIG. 3, the birds 27 are mounted to the base and / or the walls of each bird 28, 29 to guide and maintain the casting to the desired indexed position within the birds 27. It further includes a setting device 32. The positioning device comprises a guide pin 33 as shown in FIG. 3 or a notch or groove indicated by dashed line 34 in FIG. 3 or directing and directing the casting to the desired indexed position or orientation. For other similar devices. In general, the guide pin 33 is formed of a metallic material such as cast iron or a similar material having high thermal resistance, and is mounted to any side wall of the base or saddle. Corresponding locators or guide openings (shown in dashed lines) are generally in the casting during the casting process, either by the use of guide pins mounted to the bottom or sidewall of the die, or by the use of degradable sand cored materials. Will be formed. As the casting is placed in the saddle, the guide pin is received in the corresponding guide opening of the casting, thereby placing and holding the casting at the desired, indexed position with known, defined x, y, z coordinates, and likewise The position of the core entry opening is oriented and aligned at a known position, making it possible to apply heat more effectively and directly to the sand core in the casting to improve the removal of sand material for regeneration.

In addition, in some applications, the die may comprise a “chill” or insert of steel or iron having various design features of the casting imposed for the improved grain structure of the casting. This cooling mold may be removed after injection or left with the casting during solidification of the molten metal of the casting and remain as part of the casting. When left in the casting, the cooling mold is used as a positioning device to allow the casting to be positioned in the saddle at the desired alignment or position. The features or details left by the removal of the cooling mold also serve as positioning points for engagement of the guide pin or other positioning device in the saddle to keep each casting in the desired, indexed position.

As shown in Fig. 1, each casting 11 is placed in a saddle with x, y, z coordinates of known position or orientation, and then each casting is saddle for heat treatment, core removal and sand regeneration if desired. Within the heat treatment station. The saddle is generally carried or moved through a heat treatment station on a conveyor or rail so that the casting is kept in a known and indexed position as it is moved through the heat treatment station. The heat treatment station 40 generally includes a heat treatment furnace, generally a gas ignition furnace, having a series of heat treatment zones or chambers for heat treatment of each casting and removal and regeneration of the sand material of the sand core. The number of heat treatment zones is divided into as many zones as needed for the heat treatment and removal of the sand core in the individual application, and each casting will generally be able to move the casting through the heat treatment station. Until it remains in the die. If desired, the casting can be further aged in heat treatment station 40.

Examples of heat treatment furnaces or systems in which the heat treatment of the casting is carried out in conjunction with the removal of the sand core from the casting, and potentially in conjunction with the regeneration of sand from the sand core of the casting, are described in US Pat. No. 5,294,094, 5,565,046 and 5,738,162. Other examples of heat treatment furnaces for heat treatment in metal castings and furnaces, removal of sand cores, and sand reclamation that can be used with the present invention are also filed in the US patent application filed May 17, 1999, which is likewise incorporated herein by reference No. 09 / 313,111.

As shown in FIG. 1, the heat treatment station 40 is a series of nozzle stations 41 positioned at spaced intervals along the length of the heat treatment station to enhance heat treatment and removal of sand cores from the casting. It includes. The number of nozzle stations positioned along the heat treatment station varies as needed depending on the design of the core print or casting. Each nozzle station or assembly 41 includes a series of nozzles 42 mounted and oriented in a known or recorded position that corresponds to a known and indexed position of the casting to be passed in the saddle. The number of nozzles at each nozzle station is variable depending on the core prints of the casting, so that different types of castings having different core prints use different arrangements or different numbers of nozzles selectively per nozzle station. The nozzles are generally controlled by a remotely operated control system to couple or separate the various nozzles at different nozzle stations as needed, depending on the core print of the casting through the design or heat treatment station.

Each nozzle 42 is generally aligned with one of a set of core holes, inlet openings, core prints or core holes formed in the mold according to the known or indexed position or orientation of the saddle, so that the desired position and And / or mounted in orientation. Each nozzle may have a higher or lower pressure, as needed, for use in special casting applications, but generally air, heating oil, salt, water or other known induction at the core opening under high pressure of approximately 1000 FPM to 15000 FPM A high pressure heating fluid is supplied that includes the fluids. The pressurized fluid flow or jet applied to the casting by the nozzle impacts or contacts the sand core in the casting, causing the bonding material of the sand core to be at least partially scraped or broken. As the sand core is broken or dispersed by the fluid flow, the sand of the sand core is removed or washed from the mold through the core hole or entry opening with the passage of the fluid flow through the mold for recovery and regeneration of the sand.

The nozzles 42 of each nozzle assembly or station 41 are adjusted to different nozzle positions according to the properties of the mold, and the pressure of the flow or blowout is also adjusted. Adjustment of the nozzle is performed remotely with the use of a robotically movable or positionable nozzle. The fluid from the nozzle is also applied at a different temperature depending on the location of the zone within the heat treatment station of the nozzle being dispensed so that when the fluid flow moves through the heat treatment furnace or station, it does not negatively interfere with the heat treatment process for the casting. . In addition, the nozzles of each nozzle station may include a seating position to an application position oriented toward the core hole or entry opening during movement of the casting to each other zone or station within the heat treatment station, or a variety of movements between various application positions. Moving between nozzle positions, the high pressure flow of the heating fluid is intentionally flowed to other core holes or entry openings, causing the sand core to break and be removed from the mold for removal of the sand core. Thus, the use of a nozzle station in a heat treatment furnace or station improves and enables more efficient disassembly and removal of sand cores from each casting during heat treatment of the casting, and aids in the regeneration of sand material from the sand core for reuse. .

As shown in FIG. 1, after the heat treatment and core removal for each casting have been completed, each casting is removed from the heat treatment station 40 and generally moved to the quenching station 45. Quench station 45 generally includes a quench tank filled with a cooling fluid, such as water or other known material in which each casting is immersed for cooling and quenching. In general, the capacity and size of the quenching tank is a function of the specific heat of the metal or metal alloy comprising the castings and castings formed and the temperature at which each casting is heated. Optionally, the quench station comprises a series of air nozzles for applying cooling air to the casting for quenching.

Another embodiment of the present invention illustrating heat treatment in a die of a casting is shown in Figures 4-8B. As shown in FIG. 4, in this embodiment of the casting process 50, molten metal or alloy M is injected into the die 51 at the injection or casting station 52. As shown in Figures 4-8B, the die 51 in this embodiment generally comprises a flask-shaped mold formed from a metal, such as cast iron or a similar material, or mixed with an organic binder known in the art. It may be a green sand mold formed from and generally includes an internal chamber in which casting 53 (see FIGS. 6-8B) is formed. Each die 51 is generally associated with an organic binder to form bore and / or entry openings or core holes in the casting formed within the die and to produce casting details or core prints, as shown in FIG. It further comprises a sand core 54, formed from the mixed sand material. In this embodiment, the die 51 generally further includes a port or die entry opening 56 (see FIGS. 4-5B) formed at a desired location selected for the die and extending through the sidewall of the die 51. Thus, while in the die, heat is applied directly to the mold and provides a passage for the mold 53 formed in the die (see Figures 6-8B) for removal and removal of the sand core.

A heating element, such as a heated air blower or other suitable gas or electric ignition heater mechanism 58 (see FIG. 4), is adjacent to the injection or casting station 52 to preheat the die when the molten material M is introduced therein. Is also provided. Optionally, the die is formed with a cavity adjacent to the casting in the die, where the heated air, thermal oil or other heating medium is received to preheat the die and further heat the casting in the die. Generally, the die is preheated to the desired temperature depending on the heat treatment temperature required for the metal or alloy used to form the casting (eg, 400 to 600 ° C. for aluminum). The preheating of the die maintains the temperature of the casting formed in the die at or near the heat treatment temperature for the casting when the die is transported from the injection station, minimizes losses and at least partially heat treats the casting as it solidifies, Since the casting does not need to be significantly reheated to raise the temperature to the extent necessary for the heat treatment, the heat treatment of the casting is improved by reducing the number of heat treatments.

Thus, once each die 51 is filled with molten material M, the die is generally moved from the casting or injection station 52 to the loading station 61 by the die moving mechanism 59. Die movement mechanism 59 generally includes a die movement robot, winch, conveyor or other type of movement mechanism known in the art for moving a die from an injection station to a loading station. The moving mechanism is known at the loading station and positions each die at the indexed position, and the x, y, z coordinates of the die are located in a known orientation or arrangement for thermal processing.

In this embodiment of the invention, the die is then generally moved to and through the heat treatment station 62 to at least partially heat treat the casting and break the sand core for removal. As noted above, the heat treatment station 62 has a heat treatment furnace, generally a gas ignition furnace, at least partially having a series of treatment zones or chambers for applying heat to the die for “in-die” heat treatment of the casting. Mostly included. The number of treatment zones or chambers is divided into as many zones as required for the individual application, depending on the treatment of the casting. In addition, after at least partial heat treatment of the casting while in the die, the casting is removed from the die and passed through a heat treatment station for continued heat treatment, sand core removal and possible sand reclamation.

Examples of heat treatment furnaces for heat treatment and at least partial breakage and / or removal of sand cores, or subsequent heat treatment from the castings after removal from the die, sand core removal and possible regeneration of core sand while the casting is in the die are described. US Pat. Nos. 5,294,994, 5,565,046 and 5,738,162, which are incorporated herein by reference. Another example of a heat treatment furnace for use with the present invention is described in US patent application Ser. No. 09 / 313,111, filed May 17, 1999, which is likewise incorporated herein by reference. This heat treatment furnace also enables regeneration of sand from the sand core of the casting that is removed through the die entry opening during the heat treatment of the casting while the casting is in the die.

As shown in FIGS. 4-5B, the heat treatment station 62 generally further comprises a series of nozzle stations 63 or assemblies each equipped with a plurality of nozzles 64. The nozzle of each nozzle station is generally aligned with a known position of any die entry openings 56 or sets of a constant nozzle or die 51 and is oriented in a known position and / or orientation. The number of nozzle stations and the number of nozzles in each station heat-treat the casting to allow control of the heating of the die and the casting, and vary the degree of heat to the die for adjustment of heating to different stages of the heat treatment of the casting. And / or vary as needed to provide in amounts.

Each nozzle generally has a jet of fluid flow or heating fluid directed towards the die and generally toward a set of die inlet openings or dies of each die, as shown in FIGS. 5A and 5B. Supply. The fluid medium applied to the die generally includes water, air, thermal oil, salt or other conventionally known fluids supplied under high pressure and at variable temperatures for heating the die, and the fluid flow of the fluid flow supplied by the needles The temperature is controlled to fit different heat treatment steps as the casting passes through another nozzle station of the heat treatment station. The introduction of heating fluid into the die through the die entry openings causes breakage of the binder for the sand core of the casting, such that the sand core is at least partially scraped and removed from the casting and / or removed from the casting, Pass through the die entry opening with the discharge of fluid. In addition, when the die passes through the nozzle station to more directly apply the heating fluid to the casting and core openings for heat treatment and sand core removal, the die is also potentially at least partially open.

In addition to passing the casting through a series of nozzle stations including a nozzle mounted at a fixed position at the mating position or at a known position of the die, and therefore at a fixed position corresponding to the known position of the die entry opening, It is also possible to maintain the die in a fixed casting position of a single nozzle station or injection station for this purpose. In this embodiment, the nozzle 64 '(see FIGS. 5A and 5B) is generally between a series of predetermined fluid applications or nozzle positions as shown by arrows 66 and 67 in FIGS. 5A and 5B. Robotically actuated to be movable. When the nozzle 64 'is moved relative to the die in the direction of arrows 66 and 67, the nozzle is directed to a heating, pressurized fluid medium (die), which is typically directed towards and into the entry opening 56. F) is applied to raise and maintain the temperature of the die at a temperature sufficient to heat treat the metal casting as the molten metal of the casting solidifies. Various applications or nozzle positions of the movable nozzles are generally determined or set according to known x, y, z coordinates of the die and the die entry opening during positioning of the die at the injection station or at the loading station by the die movement mechanism.

The die 51 of the present invention typically has the ability to be heated to approximately 450 to 650 ° C. or higher, depending on the melting heat treatment temperature required for the alloy or metal of the casting required, and is typically preheated to a sufficient temperature. It allows at least partial heat treatment of the casting during the injection of molten metal. The heating of the die is controlled through the control of the temperature of the fluid medium applied to the die to heat the die at the desired temperature for the heat treatment of the metal of the casting formed to minimize heat loss during delivery to the heat treatment station. Maintenance and also minimizes the amount of reheat required to raise the casting to the heat treatment temperature.

In an alternative embodiment of the heat treatment station shown in FIGS. 6-8B, the nozzle station is additional heat, in which energy is supplied or directed to the die to raise and maintain the temperature of the die at the temperature required for the heat treatment of the casting. It is supplemented or replaced with processing chambers. In a first embodiment of the heat treatment chamber 70 shown in FIG. 6, a die or sand mold pack 51 is conveyed or transported for movement through the heating chamber 70 as shown by arrow 72. It is normally located on the instrument 71. As shown in the embodiment of Figure 6, the heating chamber 70 is a long furnace chamber with a thermal insulation floor, side and ceiling, and includes a radiant energy source 73. The radiant energy source 73 is generally mounted to the ceiling of the heating chamber 70, but the radiant energy source can also be mounted to the sidewalls and when the die is moved through the heating chamber 70 on a conveyor or transfer mechanism, It will be appreciated by those skilled in the art that multiple radiant energy sources may be mounted on the sidewalls, above and / or below the die. In general, the radiant energy source may be an infrared emitter or other known form of radiant energy source.

The radiant energy source is generally direct radiation from approximately 400 to 650 ° C. with a die passing through the heating chamber, and is generally direct to the side and / or top of each die, as shown by arrow 74. The die and the internal casting are irradiated with radiant energy sources for a desired time, depending on the casting metal being heat treated. Radiant energy sources are generally absorbed by the die, causing the temperature of the die to increase significantly to heat the die and the castings therein.

Figure 7 illustrates another optional heating chamber 80 for use in the in-die heat treatment of the present invention. As shown in FIG. 7, the heating chamber 80 is a long furnace generally having a bottom, ceiling and sides insulated, and a conveyor for moving the die and the casting therein through the heating chamber 80 in the direction of arrow 82. Or other transportation mechanism 84. The heating chamber 80 also includes an induction energy source 83 for applying induction energy to a die or mold pack and to the casting and sand cores 53 and 54 contained therein. Induction energy sources generally include conducting coils, microwave energy sources or other known induction energy sources or generators and, like the radiant energy source of FIG. 6, along the ceiling of the heating chamber 80, on the die, along the sides of the heating chamber, Or both. The induction energy source generates a wave of high energy field, indicated by arrow 84, directed toward the top and / or side of the die 51 and counteracts the metal casting in the mold pack by heating the casting and the die from inside to outside. Specific frequencies or frequencies that are absorbed by the sand core 54 such that the temperature of the sand core and the casting is increased for thermal treatment.

Another optional configuration of a heating chamber 90 for use in the present invention for heat treatment of a casting while in the die by applying energy to the die and the casting to increase the temperature is shown in FIGS. 8A and 8B. The die may generally be a flask type, but in this embodiment includes a sand mold pack. As shown in Figures 8A and 8B, the heating chamber 90 is an elongated furnace chamber that includes a conveyor or conveying mechanism for conveying the die in the direction of arrow 92 with the casting contained therein. As the die and casting are moved through the heating chamber 90, they pass through the slow oxygen chamber 93. The oxygen chamber generally includes a high pressure upstream side 94 and a low pressure downstream side 96 positioned opposite one another to assist in the induction of oxygen flow through the die. As indicated by arrows 97 and 97 '(see FIGS. 8A and 8B), as the die passes through the low speed oxygen chamber of the heating chamber 90, the heated oxygen gas is induced and pressurized through the die or mold pack. . As oxygen gas flows through the die or mold pack and flows from the high atmospheric side to the low atmospheric side of the oxygen chamber, a portion of the oxygen burns with the binder material of the sand mold pack and the sand core, thereby improving combustion of the binder material in the heating chamber. Let's do it. As a result, the mold packs and castings are further energized from improved combustion and oxygen of the binder material, increasing the temperature of the castings in the mold packs, while at the same time allowing the mold packs and sand cores to be easily removed and regenerated in the same form. Break the binder. As shown in Figs. 8A and 8B, the low speed oxygen chamber has a vertical direction (see Fig. 8A) or a substantially horizontal direction to pressurize the hot oxygen gas through the mold pack, depending on the size and space configuration for the heating chamber. (See Fig. 8B).

It is also possible to reduce the potential heat transfer loss between the molten material and the die surface and loss to outside air by including an energy source in the die while increasing the temperature of the die or mold pack for in-die heat treatment of the casting. do. In this embodiment, the die is generally formed with a cavity or chamber adjacent to the internal cavity in which the casting is formed. Then, a heating fluid medium, such as thermal oil, water or similar or other material that can easily retain heat, is fed to the die structure in which the cavity is received. This heating fluid helps to increase and maintain the temperature of the casting at the desired level needed for heat treatment.

As a result of applying energy to the die or mold pack, the die is heated to the desired temperature and maintained at the temperature necessary to heat treat the casting formed therein as the molten metal of the casting solidifies in the die. Immediately after the injection of the molten metal material into the die, when the metal of the casting generally rises in temperature and stabilizes at the heat treatment temperature, this in-die heat treatment of the casting may result in, for example, heat treatment casting from about 250 minutes to about 50 minutes. By significantly reducing the processing time required for this, the heat treatment of the casting takes place within a relatively short time after injection of the molten metal material into the die. The rise of the temperature of the die to the heat treatment temperature for the heat treatment of the casting further enhances the combustion and decomposition of the flammable organic binder of the sand core and / or sand mold, thereby demolishing the sand core and sand mold of the heat treatment and casting process. And further reduces the time required for regeneration.

After heat treatment of the casting in the die in the heat treatment station 62, the casting is generally removed from the die and, if necessary, an additional heat treatment station for completion of the heat treatment of the casting and removal of the sand core and possible regeneration of the sand material of the core. Is moved to. The casting is then moved to the quenching station 100 for quenching and cooling the casting. Optionally, as shown in Figure 4, the casting is removed from the die and conveyed directly to the quenching station. Quenching station 100 generally includes a quenching tank that includes a cooling fluid, such as water or other known cooling material, but the quenching station also includes reference numeral 101 in FIG. 4 which applies a cooling fluid, such as air or water, to the casting. It includes a chamber having a series of nozzles. Quenching is also done in an adjoining quenching apparatus close to the injection station so that cycle time and temperature variations are minimized for the setting and processing of the molten metal material of the die in the die.

After the heat treatment and sand removal of the casting have been completed, the casting is removed from the die and immersed in the quenching tank of the quench station to cool the casting before the next process, after which the sand removed from the casting is recycled for later reuse. It is also possible to move the die directly from the infusion station to the quench station, as shown by the dashed line in FIG. For example, after a die from an injection station is heated to a heat treatment temperature at or near the injection station for heat treatment of the casting, the die is transferred directly to the quenching station.

Thus, the present invention makes it possible to reduce or eliminate the requirement for further heat treatment of a casting once removed from the die, while in the die, heated to provide solution heating time and cooled to provide the necessary quenching effect, Significantly reduces the amount of heat treatment / process time required to form metal castings. The present invention is also improved or better by inducing fluid flow in a casting at a predetermined location, which corresponds to a known orientation or alignment of the casting and / or die having the casting therein as it passes through the heat treatment station. It enables effective heat treatment and the decomposition and removal of the sand core in the casting.

Although the invention has been described above with respect to preferred embodiments, it is understood by those skilled in the art that various additions, modifications and variations can be made without departing from the spirit and scope of the invention as set forth in the appended claims. Can be.

Claims (31)

In a method for treating a known metal casting, Injecting molten metal into the die; Retaining the metal in the die for a time sufficient to at least partially solidify the metal to form a core and a casting having core openings therein; Positioning the casting at the indexed position such that at least the plurality of core openings are oriented at a known position aligned with the plurality of nozzles; Directing fluid flow from the nozzle into the core openings towards the core openings to remove the core from the casting. The method of claim 1, further comprising aligning at least the plurality of core openings with the second plurality of nozzles, and directing fluid from the second plurality of nozzles into the core inlet openings toward the core inlet openings. Method comprising a. 2. The method of claim 1, further comprising removing the casting from the die prior to positioning the casting at the indexed position. 4. The method of claim 3, wherein positioning the casting at an indexed position includes positioning the casting at a first position in which the x, y, z axes of the casting are oriented in a known first orientation, and at least a plurality of And wherein the core openings are aligned with the first plurality of nozzles. The method of claim 1, further comprising: removing the casting from the die prior to positioning the casting at the indexed position; Positioning the casting at a first position in which the x, y, z axes of the casting are oriented in a known first orientation such that at least the plurality of core openings are aligned with the first plurality of nozzles; Directing fluid flow from the first plurality of nozzles to the core opening; Positioning the casting at a second position in which the x, y, z axis of the casting is oriented in a second orientation different from the known first orientation such that at least the plurality of core openings are aligned with the second plurality of nozzles; Directing fluid flow from the second plurality of nozzles of the core aperture. The method of claim 1, further comprising: positioning the casting at a first casting position where the x, y, z axes of the casting are oriented in a known orientation; Moving the plurality of nozzles to the first nozzle position in alignment with at least the plurality of core entry openings; Moving at least some of the plurality of nozzles to a second nozzle position, Wherein some of the plurality of nozzles are aligned with at least the second plurality of core openings. The method of claim 1, further comprising: moving the casting from the die to the saddle; Positioning the casting on the saddle such that the casting's x, y, z coordinates are known. In the method of processing a metal casting, Providing a die with a casting core, Preheating the die to a temperature sufficient to at least partially heat treat the metal of the casting; Injecting molten metal into the die; At least partially heat treating the metal in the die to form a casting having a core casting forming a core opening in the metal casting; Removing the core from the casting. The method of claim 8, further comprising: aligning the plurality of core openings with the first plurality of nozzles; Directing the fluid flow from the first plurality of nozzles towards the core opening. 10. The method of claim 9, further comprising: aligning the plurality of core openings with the second plurality of nozzles; Directing fluid flow from the second plurality of nozzles towards the core opening. 10. The method of claim 9, wherein aligning the core entry opening with the first plurality of nozzles comprises positioning the casting at a first location having x, y, z coordinates of the casting of known first orientation. At least the plurality of core openings are aligned with the first plurality of nozzles. 10. The method of claim 9, further comprising: removing the casting from the die; Positioning the casting in a first position such that the x, y, z axes of the casting are oriented in a known first orientation in which at least the plurality of core openings are aligned with the first plurality of nozzles; Applying a fluid to a casting having a first plurality of nozzles to at least partially remove the core from the casting; Positioning the casting at a second position, wherein the x, y, z axis of the casting is oriented in a known second orientation different from the first orientation and at least the plurality of core openings are aligned with the second plurality of nozzles; , Applying the fluid to a casting having a second plurality of nozzles. The method of claim 8, wherein at least partially heat treating the casting comprises: Maintaining the die and casting in a known position; Moving the plurality of nozzles to the first nozzle position relative to the die; Applying heat to a die having a nozzle to at least partially remove the core from the casting, Moving at least some of the plurality of nozzles to a second nozzle position; Further applying heat to a die having a nozzle at a second nozzle position to further heat treat the casting within the die. The method of claim 8, wherein the metal comprises aluminum and the preheating step comprises preheating the die to a temperature in the range of 400-600 ° C. 10. The method of claim 8 further comprising maintaining the temperature of the die in a range sufficient to at least partially heat treat the metal of the casting for a time sufficient to complete the heat treatment of the metal of the casting. 9. The method of claim 8, further comprising moving the casting through the plurality of nozzle stations, each station being equipped with a plurality of nozzles. 9. The method of claim 8, wherein the casting core is formed of sand and further comprising regenerating core sand with removal of the core from the casting. 10. The method of claim 8, further comprising quenching the casting. An apparatus for producing a casting from molten metal, A series of dies in which molten metal is received to define and mold the casting, A series of birds configured to receive the casting in a desired orientation with known, indexed position coordinates, Birds with castings located within the indexed position, known therein, include a heat treatment station housed for heat treatment and core removal of the casting, The heat treatment station includes a plurality of nozzle stations, each installed with a plurality of nozzles arranged in alignment with known position coordinates of the casting to apply fluid flow to the casting to substantially remove the core from the casting. Device. 21. The robot of claim 20, wherein each of the nozzle stations is robotically configured to move relative to the casting between at least first and second nozzle positions to direct fluid flow from the other direction to the casting to substantially remove the core from the casting. And a series of nozzles actuated. 21. A series as recited in claim 20, wherein each of the birds defines a casting receptacle and a plurality of positioning devices located within the casting receptacle to engage and guide the casting to a known, indexed location having a known positional coordinate within the saddle. Apparatus comprising the walls of the. 23. The die of claim 22 wherein the positioning device comprises a guide pin and the casting includes the dies having a corresponding positioning opening through which the guide pin is received to position the casting at a known, indexed position within the saddle. Apparatus characterized in that it is molded in. 21. The apparatus of claim 20, wherein the dies include a flask-type mold having a heating source for preheating the dies and at least partially heat treating the casting. 21. The apparatus of claim 20 further comprising a quench station for quenching the casting. An apparatus for producing a metal casting, A die in which a metal material is received to form a casting, A heat treatment station comprising a heat treatment chamber in which the dies are subjected to heat to at least partially heat treat the casting in the dies, And the heat treatment station comprises means for heating the dies to a temperature sufficient to at least partially heat treat the interior casting. 27. The system of claim 25, wherein the heating means is positioned within the die for positioning fluid along the heat treatment station and for applying a fluid medium to the die to heat the die and remove core material of the core in the casting. At least one nozzle station having at least one nozzle aligned with the die entry opening and initially mounted. 27. The apparatus of claim 25, wherein said heating means comprises a radiant energy source mounted within said heating chamber to direct radiant energy to said die. 26. The apparatus of claim 25, wherein said heating means comprises an induction energy source mounted in said heating chamber for delivering induction energy to said die. 26. The apparatus of claim 25, wherein the heating means is positioned along the heat treatment station to direct the flow of oxygen through the die to react and burn with the binder material to increase the temperature of the casting in the die. And an oxygen chamber. 27. The apparatus of claim 26, wherein the heating means further comprises an energy source positioned within the heating chamber for applying energy to the die to heat the die from the inside to the outside. 26. The apparatus of claim 25, further comprising a quench station for quenching the heat treated casting.