JP3817476B2 - Heat treatment and sand removal for castings - Google Patents

Abstract

A system and method for heat treating castings (13, 53) and removal cores (54) therefrom. The castings (13, 53) are initially located in indexed positions with their x, y, and z coordinates known. The castings (13, 53) are passed through a series of nozzle stations (41, 63) each having a series of nozzles (42, 64, 64') mounted in present positions corresponding to the known indexed positions of the castings passing through the nozzle stations (41, 63). The nozzle (42, 64, 64') apply heated fluids to the castings (13, 53) for heat treating the castings (13, 53) and dislodging the sand cores (54) for removal from the castings (13, 53).

Description

[0002]
(Technical field)
The present invention relates generally to a metallurgical casting method, and more specifically to a method and apparatus for removing a sand core from a casting and heat treating the casting.
[0003]
(Background of the Invention)
Traditional casting methods for forming metal castings use, for example, cast iron flask molds or sand molds (also called dies), which on the inner surface have external features of the desired casting (eg, A cylindrical head) is formed. A sand core composed of sand and a suitable binder material and the definition of the internal features of the casting are placed in the die. Sand cores are commonly used in these metal castings to produce contours and internal features, and after the casting process is complete, removing and reclaiming the core sand material from these castings Indispensable. Depending on the application, the sand core and / or sand mold binder, if used, can be comprised of a phenolic resin binder, a phenol urethane “cold box” binder, or other suitable organic binder material. This die is then filled with a molten metal alloy. When the alloy has solidified, the casting is generally removed from the die and then transferred to a processing furnace for heat treatment and for regenerating and aging sand from the sand core. Heat treatment and aging are the steps to adjust the metal alloys so that they have different physical properties suitable for different applications.
[0004]
In accordance with some of the prior art, once this casting is formed, generally there are several distinctly different steps to heat treat the metal casting to regenerate sufficiently pure sand from the sand core. Must be executed. The first step separates a portion of the sand core from the casting. The sand core is typically separated from the casting by one means or a combination of means. For example, the sand can be carved away from the casting, or the casting can be physically shaken or shaken to grind the sand core and remove the sand. Once the sand is removed from the casting, heat treatment and aging of the casting is generally performed in subsequent steps. The casting is typically heat treated if it is desired to strengthen or cure the casting. The additional step consists of refining the sand separated from this casting. This purification step is typically carried out by one means or a combination of means. These may include baking the binder covering the sand, polishing the sand, and passing a portion of the sand through a sieve. Thus, a portion of the sand is again subjected to a regeneration process until sufficiently pure sand is regenerated.
[0005]
Thus, there is a continuing need in the industry for more efficient methods and associated equipment (which allows for more efficient heat treatment, sand core removal, and regeneration of sufficiently pure sand from the sand core). As is desired, it is desirable to enhance the process of heat treating the casting and reclaiming the sand core material therefrom.
[0006]
(Summary of the Invention)
Briefly described, the present invention includes a heat treatment casting system and method for removing sand cores used, for example, in metallurgical plants and used during the casting process. The present invention includes embodiments that use a high pressure fluid medium to efficiently remove and regenerate sand in the sand core for in-die heat treatment of the casting.
[0007]
In one embodiment of the present invention for sand core removal and cast heat treatment, the molten metal is cast into a die, which dips the temperature of the metal as the cast is formed in the die. In order to maintain near the heat treatment temperature, it is typically preheated. The castings are then removed from their dies and each placed in a defined position on the saddle, which has a known x-axis, y-axis and z-axis and orientation. Each saddle generally has the x-, y-, and z-coordinates of the casting at a known position so that the core opening of the casting formed by the sand core is oriented or aligned at a known alignment position. Positioned in the mating position or orientation and configured to receive the casting in a fixed orientation or position. The saddles can further include alignment devices that help guide and maintain the castings in their known alignment positions.
[0008]
Each saddle has a casting located therein and is moved through a heat treatment furnace or chamber of a heat treatment station for heat treatment and removal of the core, and for potential regeneration of the sand core. While passing through the heat treatment station for the heat treatment, a series of nozzles (which have x, y and z coordinates fixed or set aligned with the position of the casting) are heated at high pressure. A fluid medium (eg, air, water, or heat transfer oil) is directed onto and into the casting. The fluid flow tends to remove and assist in removing the sand of the sand core from the internal cavity of the casting as the sand core breaks at the heat treatment station. Typically, the nozzles are arranged in a series of nozzle stations, the nozzle stations being located sequentially through the thermal processing chamber, wherein the nozzles at each nozzle station are the castings. Are oriented in a defined arrangement corresponding to known locations of the core openings, and each nozzle assembly can be remotely operated by a control system or station.
[0009]
In another embodiment of the invention, the castings can remain in their dies for “in-die” heat treatment of the castings. The die typically includes casting the molten metal of the casting therein to partially heat treat the casting in the die while the casting is solidified. Prior to maintaining the metal close to the heat treatment temperature for the casting, it is preheated. The dies are then positioned or placed with their castings therein, typically in aligned orientations or positions, and their x, y and z coordinates are within them. It is known to heat treat the casting and remove the sand core.
[0010]
In order to heat treat and to remove and regenerate the sand core of the casting, the dies and casting are generally passed through a heat treatment furnace in a heat treatment station. The heat treatment station further includes a plurality of nozzle stations, each of which is a series of nozzles oriented or positioned in a defined manner corresponding to known locations of the die and casting for applying high pressure fluid thereto. Have The nozzle station also includes a robot actuated nozzle that is positioned or oriented in a die access opening or device in the die for accessing the casting to remove the sand core from the casting. Move along a defined path around the die to various application positions corresponding to. Alternatively, the heat treatment station can also provide an alternative energy source (eg, an inductive or radiant energy source) that provides energy to the die or mold pack to increase their temperature to heat treat the casting therein An oxygen chamber can be included. The castings are then removed from their dies and passed through a subsequent core removal station or process to further remove the sand core from the casting and potentially regenerate.
[0011]
In a further embodiment, the die is preheated to a specified temperature. Thereafter, as the molten metal is cast into the die, the die continues to be heated to heat treat the casting as they solidify without removing the casting from the die. The die can then be moved to a quench station to quench the casting and remove the sand core therefrom. In this embodiment, the dies are generally maintained in a known fixed position or orientation adjacent to or adjacent to the casting station. The die is typically heated by applying heated fluid from a series of nozzles located around the die in alignment with the die access opening. The nozzle further moves around the die between a series of nozzle positions set according to the position or orientation of the die to subsequently heat the die and heat treat the casting within the die. Is done.
[0012]
Various objects, features and advantages of the present invention will become apparent upon reading and understanding this specification in conjunction with the accompanying drawings.
[0013]
(Detailed description of the invention)
Referring now in greater detail to the drawings (where the same numerals refer to the same parts throughout the several views), FIG. 1 generally illustrates the metallurgical casting process. Casting processes are well known to those skilled in the art, and traditional casting processes are described only slightly for reference purposes.
[0014]
As illustrated in FIGS. 1 and 2, according to the present invention, the molten metal or metal alloy M is cast into a casting or casting station 12 (eg, cylinder head or automatic) that forms a casting 13 (FIG. 3). car The engine block is cast into the die 11. Typically, the casting core is housed or installed to create hollow cavities and / or casting details or core prints within the casting formed within each die. Each of the dies 11 is typically a flask mold and has a bivalve shell style design to facilitate the opening and removal of the casting therefrom, as is known in the art. And can be formed from a metal such as cast iron or other material. The die can also be a green sand mold, which is formed from a sand material mixed with a binder (eg, a phenolic resin or other suitable organic binder material known in the art). Similarly, the cast core typically includes a sand core, which includes a sand material and a suitable binder (eg, a phenolic resin, a phenol urethane “cold box” binder, or other suitable organics known in the art). Binder material).
[0015]
As illustrated in FIG. 3, each die 11 generally includes a series of side walls 14, a top wall (top wall) 16 and a bottom wall (bottom wall) 17 that define an internal cavity 18. In which the molten metal M is received. The internal cavity 18 is generally formed with a relief pattern that creates the internal features of the cast 13 formed within this die to define the shape or configuration of the final cast. A casting opening 19 is generally formed at the top wall or top 16 of each die, as shown in FIGS. 1 and 2, so that molten metal M can be cast or introduced into the die, and an internal cavity 18 and I'm in touch. The resulting casting has the features of the internal cavity of this die, in which additional core openings or access openings 21 are also formed, where these sand cores are located within these dies. Is located.
[0016]
Casting station to preheat the die 11 1 Adjacent to 2, a heating element (eg, a hot air blower or other suitable gas or electric fuel heater mechanism 22) is also provided. Alternatively, these dies can include a heating source or heating element that heats the dies. For example, these dies can include cavities adjacent to the casting in which a heating medium (eg, heat transfer oil) is contained to heat the dies. Typically, these dies are preheated to the desired temperature, depending on the metal or alloy used to form the casting. For example, for aluminum, these dies are preheated to a range of about 400-600 ° C. The various preheating temperatures necessary to preheat various metal alloys and other metals to form castings are well known to those skilled in the art and range from 400 ° C to 600 ° C and below and a wide range of temperatures. Can be included. Preheating these dies helps to maintain the metal in these castings at or near the heat treatment temperature to minimize heat loss as the molten metal is cast into the dies and solidifies. The dies are then moved to subsequent processing stations to heat treat these castings.
[0017]
As shown in FIG. 1, once this molten metal or metal alloy is cast into a die and at least partially solidified into a casting, the die and casting are cast by a casting station 12 by a die moving mechanism 25. And is moved to the loading station 26. The die moving mechanism may include a die moving robot (not shown), a winch or other type of conventionally known moving mechanism for moving the die from the casting station to the loading station. In the first embodiment of the present invention, after the molten metal M solidifies in the die to form the casting, the casting 13 (FIG. 3) is, for example, by a robot arm or similar mechanism, At the loading station 26 (FIG. 1), it is removed from the die 11 and placed in a saddle 27 at a defined alignment position along with its known x, y and z coordinates. As a result, the core openings 21 (FIG. 3) of these castings are similarly oriented or aligned at known locations that remove the sand core from these castings.
[0018]
As shown in FIG. 3, each saddle is generally a basket or carrier, which is typically formed from a metallic material and contains an open casting chamber or receptacle 31 in which the casting 13 is received. With a base 28 and a series of side walls 29, the core opening or access opening of which is exposed. These castings are generally fixed in a known alignment orientation or position when installed in the receptacle 31 of their saddles 27. In addition, as shown in FIG. 3, the saddle 27 can further include a positioning device 32 that guides and maintains these castings in their desired alignment positions within the saddle 27. In order to do so, it is attached to the base and / or walls 28 and 29 of each saddle. These positioning devices can include, for example, guide pins 33, as shown in FIG. 3, or can include, for example, notches or grooves shown in broken lines in FIG. Other similar devices can be included that guide or direct the position or orientation. Typically, the guide pin 33 is formed from a metallic material (e.g., cast iron, or a similar material having high heat resistance) and is attached to the base of this saddle or any side wall. Corresponding locators or guide openings 36 (shown in dashed lines) are generally used, for example, by using guide pins attached to the bottom or side walls of these dies, or degradable sand cores. Through the use of mold material, it is formed into the casting during the casting process. When these castings are installed in their saddles, these guide pins cause the castings to have their desired alignment position (which has a known prescribed x, y and z coordinates). In the corresponding guide openings of the castings, and the position of the core access openings of these castings is likewise oriented or aligned at known positions, so that these castings Allows more efficient and direct application of heat to the sand core within, increasing the removal and removal of reclaimed sand material.
[0019]
In addition, in certain applications, these dies are made of steel or iron “chills” or inserts (including various design features of the casting to improve the grain structure of the casting). Is given). These chills can be removed after casting or can remain with a portion of the casting as the molten metal in the casting solidifies. These chills can be used as positioning devices if left in the casting and also allow the castings to be located in their saddles in their desired arrangement or position. Features or details remaining from removing the chill also act as positioning points in the saddle that engage guide pins or other positioning devices to hold each casting in its desired alignment position. it can.
[0020]
As shown in FIG. 1, after each casting 11 is loaded into its saddle with the x, y and z coordinates of its position or orientation known, each casting is then In this saddle, it is moved to a heat treatment station 40 for heat treatment, core removal and sand reclamation. These saddles are generally transported or moved through the heat treatment station on a conveyor or rail so that these castings are maintained in their known alignment positions as they move through the heat treatment station. . The heat treatment station 40 generally includes a heat treatment furnace (typically a gas fuel furnace), which is a series of treatment zones or chambers for heat treating each casting to remove and regenerate the sand core sand material. Have The number of treatment zones can be divided into as many or as few zones as their individual application may require heat treatment and removal of the sand core therefrom, and each casting typically passes through a heat treatment station. Until the saddle is available to move it, it is kept inside the die. In addition, further aging of the casting in the heat treatment station 40 is possible if it is desired.
[0022]
As shown in FIG. 1, the heat treatment station 40 includes a series of nozzle stations 41, which are the length of this heat treatment station to enhance the heat treatment of these castings and the removal of sand cores from these castings. Are located at intervals. The number of nozzle stations located along the heat treatment station can vary as needed depending on the core print or design of the casting. Each of the nozzle stations or assemblies 41 includes a series of nozzles 42 that are at known positions or alignment positions corresponding to known alignment positions of the castings passing therethrough with their saddles, Attached and oriented. The number of nozzles at each nozzle station can vary depending on the core prints of these castings, and different types of castings with different core prints can have arbitrarily different arrangements or numbers per nozzle station. Nozzle will be available. These nozzles typically rely on the casting design or core print through this heat treatment station to engage or release these various nozzles at different nozzle stations as required. It is controlled via a remote control system.
[0023]
Each nozzle 42 is generally installed in a predetermined position and / or orientation and is formed in the casting according to a known alignment position or orientation within the saddle of the casting, a core opening or access opening Aligned with one of the parts or core print or set of core openings. Each of these nozzles is fed with a high pressure heated fluid, which typically includes air, heat transfer oil, salt, water or other known fluids, which are high pressure ( Therefore, Typically about 1,000 FPM (5.08m / s) ~ About 15,000 FPM (Resulting in a speed of 76.2 m / s) But higher pressure And speed Or low pressure And speed Is also directed to these core openings underneath (which can be used as required for specific casting applications). The flow or blast of pressurized fluid applied to the castings by these nozzles tends to impinge or come into contact with the sand cores in these castings, and at least partially degrade or cause these sand core binder materials to deteriorate. Decompose. As these sand cores are broken down or dispersed in the fluid flow, the sand in the sand cores, along with the passage of the fluid flow through these castings, is collected along with the core or access openings to recover and regenerate the sand. Tends to be removed or cleaned from the casting.
[0024]
The nozzles 42 of each nozzle assembly or station 41 can be further adjusted to different nozzle positions depending on the characteristics of these castings, and their fluid flow or blast pressure can also be adjusted. Adjustment of these nozzles can be accomplished remotely, for example, by using nozzles that can be moved or positioned by a robot. The fluid from these nozzles can also be applied at different temperatures, depending on which zone in the thermal treatment station of the nozzle to which they are dispensed, so that these fluid flows can be As the objects move through the heat treatment furnace or station, they do not negatively interfere with the process of heat treating these castings. In addition, the nozzles at each nozzle station can move between various nozzle positions (this includes moving from a stationary position to an application position, or moving between several application positions) Each different in this heat treatment station to dismantle the sand core and remove it from the casting that is supposed to remove the sand core by strategically directing the high pressure flow towards different core openings or access openings. As the casting is moved to the zone or station, it is oriented towards these core openings or access openings. Therefore, the use of a nozzle station within this heat treatment furnace or station enhances and allows for more efficient disintegration and removal of the sand core from each casting during the heat treatment of these castings and For use, it can help regenerate the sand material from this sand core.
[0025]
As shown in FIG. 1, after the heat treatment and core removal for each casting is completed, each casting is removed from the heat treatment station 40 and typically moved to the quenching station 45. The quench station 45 typically includes a quench tank filled with a cooling fluid (eg, water or other known material in which each casting is immersed for cooling and quenching). The capacity and size of the quench tank is generally a function of the castings that are formed, the specific heat of the metal or metal alloy that makes up these castings, and the temperature at which each casting is heated. Alternatively, the quench station can include a series of air nozzles that apply cooled air to the casting for quenching.
[0026]
A further embodiment of the invention illustrating the in-die heat treatment of the casting is illustrated in FIGS. 4-8B. As shown in FIG. 4, in this embodiment 50 of the casting process, molten metal or alloy M is cast into a die 51 at a casting or casting station 52. As shown in FIGS. 4-5B, the die 51 typically includes a flask mold (which is formed from a metal such as cast iron or similar material) or is green in this embodiment. It can be a sand mold (which is formed from sand material mixed with an organic binder, as is known in the art) and generally includes an internal chamber in which a casting 53 (FIGS. 6-8B) is formed. Including. Each of the dies 51 further generally includes a sand core 54, as illustrated in FIG. 7, which generally includes bores and / or core openings in the casting formed in these dies. Formed from sand material mixed with organic binder to form access openings and to create casting details or core prints. The die 51 in this embodiment further typically includes ports or die openings 56 (FIGS. 4-5B) that are formed at selected desired locations around the die and are within the die. To provide access to the casting 53 (FIGS. 6-8B) formed in these dies in order to directly apply heat to the casting in between and to remove and remove the sand core therefrom. And extends through the side wall 57 of the die 51.
[0027]
As the molten material M is introduced, a heating element (eg, a heated air blower or other suitable gas or electric fuel heater mechanism is adjacent to the casting or casting station 52 to preheat these dies. 58 (FIG. 4)) may also be provided. Alternatively, these dies can be formed with cavities adjacent to the castings in the dies, where heated gas is used to preheat the dies and to further heat the castings in the dies. Heat medium oil or other heating medium can be accommodated. Typically, these dies are brought to the desired temperature depending on the heat treatment temperature required for the metal or alloy used to form the casting (ie, 400-600 ° C. for aluminum). Preheated. Preheating of these dies substantially maintains and minimizes the temperature loss of these castings at or near the heat treatment temperature for the castings formed in the dies as the dies are moved from the casting station. And as these castings solidify, they tend to heat treat at least partially, and the castings do not have to be significantly reheated to raise their temperature to the level required for heat treatment. The heat treatment time tends to be improved by reducing the heat treatment time.
[0028]
Thereafter, once each die 51 is filled with molten metal M, the die is typically moved from a casting or casting station 52 to a loading station 61 by a die moving mechanism 59. The die moving station 59 can generally include a die moving robot, winch, conveyor, or other type of conventionally known moving mechanism that moves the die from the casting station to the loading station. The moving mechanism positions each die at a known alignment position at the loading station, and the x, y, and z coordinates of these dies are located in a known orientation or alignment prior to heat treatment.
[0029]
In a preferred embodiment of the present invention, these die moving mechanisms are then generally moved into and through the heat treatment station 62 to at least partially heat these castings and their sand. Disassemble the core for removal. As described above, the heat treatment station 62 generally includes a heat treatment furnace, typically a gas fuel furnace, which is used to at least partially heat these castings “in-die”. It has a series of processing zones or chambers that apply heat to the die. The number of processing zones or chambers can be divided into as many or as few zones as may be required for individual applications, depending on the casting to be processed. Furthermore, following at least partial heat treatment of these castings while in the dies, these castings can be removed from their dies, and subsequent heat treatment, sand core removal and possibly sand regeneration. In order to pass through this heat treatment station.
[0030]
heat The processing furnace further allows sand to be regenerated from the sand core of the cast removed through its die access opening during their heat treatment while these castings remain in their dies. It becomes.
[0031]
As illustrated in FIGS. 4-5B, the heat treatment station 62 further generally includes a series of nozzle stations 63 or assemblies, each with a plurality of nozzles 64. The nozzles of each of these nozzle stations are generally oriented at a known preset position and / or orientation, aligned with a known location of a particular or set of die access openings 56 of the die 51. The The number of nozzle stations and the number of nozzles at each station is used to heat treat the castings in the dies so that the heating of these dies (and hence these castings) is controllable and In order to adjust to different stages of the heat treatment of the casting, these dies can be varied as needed to supply heat in different degrees and / or amounts.
[0032]
Each of these nozzles was generally directed toward these dies (typically a specific die access opening or set of die access openings for each die) as shown in FIGS. 5A and 5B. Supply a fluid flow or blast of heated fluid. The fluid medium applied to these dies is typically water, air, heat transfer oil, salt, or other conventionally known fluid supplied at varying temperatures under high pressure to heat the dies. Of those nozzle The temperature of the fluid stream supplied by is controlled to adapt to different heat treatment stages as the casting passes through different nozzle stations of the heat treatment station. Introducing a heat transfer fluid into the dies through these die access openings generally further generally at least partially decomposes and / or removes and / or removes these sand cores during the heat treatment. In addition, the sand material that tends to cause degradation of the binder for the sand core of the casting passes through the die access opening through which the fluid is discharged. In addition, these dies also potentially cause these nozzle stations to apply the heated fluid more directly to the casting and its core opening for heat treatment and sand core removal. As it passes, it can be at least partially opened.
[0033]
These castings are placed in a series of nozzle stations, which include nozzles aligned or mounted in corresponding fixed positions at known locations of these dies (and hence known locations of these die access openings). In addition to threading, these dies can also be maintained in a fixed casting position to apply heated fluid thereto at a single nozzle station or casting station. In such an embodiment, the nozzle 64 ′ (FIGS. 5A and 5B) is typically located between a series of predetermined fluid application or nozzle positions, as illustrated by arrows 66 and 67 in FIGS. 5A and 5B. It can be operated with a robot just like it can move with. As nozzle 64 'moves around the dies in the directions of arrows 66 and 67, as the molten metal in these castings solidifies, the die 64' is at a temperature sufficient to heat treat the metal casting therein. Apply a heated and pressurized fluid medium F to these dice (which are typically directed into the access opening 56) in order to raise and maintain the temperature of the To do. The various applications or nozzle positions of these movable nozzles are generally determined by the known x-coordinates, y-coordinates of these dies and when they are positioned or positioned at the casting station or at the loading station by a die moving mechanism. determined or set according to the z-coordinate (and hence their die access openings).
[0034]
The die 51 of the present invention typically has the ability to be heated to about 450-650 ° C. or higher, depending on the solution heat treatment temperature required for the required casting alloy or metal. Typically, however, during casting of the molten metal, the casting is preheated to a temperature sufficient to allow at least partial heat treatment of the casting. The heating of these dies further reduces the amount of reheating required to raise the temperature of these castings back to their heat treatment temperature in order to minimize heat loss during transfer to this heat treatment station. Is controlled by temperature control of the fluid medium applied to the die so as to heat and maintain the die at the desired temperature required to heat treat the cast metal formed therein.
[0035]
In an alternative embodiment of the heat treatment station shown in FIGS. 6-8B, these nozzle stations can be refilled or replaced with an additional heat treatment chamber in which the die is heated to the temperature required to heat treat the casting therein. Energy is supplied or directed toward these dies in order to raise the temperature of and maintain at this temperature. In a first embodiment of the heat treatment chamber 70 (which is illustrated in FIG. 6), the dice or sand mold pack 51 is generally a conveyor for moving through the heating chamber as indicated by arrow 72. Alternatively, it is installed in the transport mechanism 71. The heating chamber 70 is typically an elongated furnace chamber, which has an insulated floor, sides and ceiling and includes a radiant energy source 73 as illustrated in the embodiment of FIG. . The radiant energy source 73 is typically attached to the ceiling of the heating chamber 70, but this radiant energy source can also be attached to the side walls, as well as multiple radiant energies can be used, which can be conveyor or transported. Those skilled in the art understand that as they move through the heating chamber 70 on the mechanism, they can be attached to the side walls, above and / or below these dies. Typically, this radiant energy source is an infrared emitter or other known type of radiation energy source.
[0036]
The radiant energy source typically directs radiant energy to a die through the heating chamber at about 400-650 ° C. 6 Directed to the side and / or top of each die, as shown in FIG. These dies (and therefore the castings therein) are exposed to this radiant energy source for a desired time, depending on the metal of the casting being heat treated. This radiant energy is generally absorbed by these dies and correspondingly increases the temperature of the dies, thereby heating the dies (and hence the castings therein) from the inside.
[0037]
FIG. 7 shows yet another alternative 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 generally an elongated furnace having an insulated floor, ceiling, and sides, which passes these dies through their heating chamber 80 along with their castings therein. Conveyor or other transport mechanism 8 to move in the direction of arrow 82 1 including. The heating chamber 80 further includes an inductive energy source 83 for applying inductive energy to these dies or mold packs (and therefore the castings and sand cores 53 and 54 contained therein). This inductive energy source can generally include a conductive coil, a microwave energy source or other known inductive energy source or source, similar to the radiant energy source of FIG. Can be positioned along the sides of the heating chamber, or both. This inductive energy source forms a wave high energy field, as indicated by arrow 84, which is directed towards the top and / or side of the die 51 and these sand cores (and therefore casting) By heating the casting (and hence the die) from the inside by raising the temperature of the object), it is absorbed by the sand core 54 to heat-treat the metal casting in these mold packs accordingly. , Is a specific frequency.
[0038]
Further, by adding energy to these dies (and hence the casting) to increase their temperature, the heating chamber 90 used in the present invention to heat treat the casting while “in the die” is further Another alternative structure is shown in FIGS. 8A and 8B. In this embodiment, these dies typically include sand-type pack dies, although flask-type molds can also be used. As shown in FIGS. 8A and 8B, the heating chamber 90 is typically an elongated furnace chamber for carrying the dies 51 with their castings 53 contained therein in the direction of arrow 92. Conveyor or transport mechanism 91 is included. As these dies and castings travel 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, which are located opposite each other to help draw oxygen flow through these dies. As these dies pass through the slow oxygen chamber of the heating chamber 90 as indicated by arrows 97 (FIG. 8A) and 97 ′ (FIG. 8B), the heated oxygen gas is directed to the dies or mold packs, where Forced to pass. As this oxygen gas is withdrawn or flows from the high pressure side of the oxygen chamber to the low pressure side and flows through these dies or mold packs, a certain percentage of oxygen is burned out with the sand mold pack and sand core binder material. Thus enhancing the combustion of the binder material in the combustion chamber. As a result, the mold packs and their castings are further supplied with energy from the increased combustion of their binder material and oxygen, thereby reducing the temperature of the castings in these mold packs. In the meantime, these mold packs and sand core binders are disassembled to facilitate removal and regeneration at the same time. As shown in FIGS. 8A and 8B, the slow oxygen chamber is oriented vertically (in FIG. 8A) depending on the size and spatial arrangement of the heating chamber to force hot oxygen gas through these mold packs. Orientation) or a substantially horizontal orientation (shown in FIG. 8B).
[0039]
In addition, the inclusion of an energy source within the die itself allows the die to be heat treated in-die while reducing potential heat loss transfer between the molten material and the die surface and atmosphere. It is also possible to carry out increasing the temperature of the sand mold pack. In such embodiments, these dies are typically formed with a cavity or chamber in close proximity to the internal cavity in which the casting is formed. The die structures contained within these cavities are then supplied with a heated fluid medium (eg, heat transfer oil, water, or similar material or other material that can easily retain heat). The heated fluid tends to increase the temperature of the casting and help maintain it at the desired level required for heat treatment.
[0040]
As a result of applying energy to the die or mold pack itself, the dies are heated to the desired temperature and the cast formed therein is heat treated as the molten metal of the cast solidifies in the die. Can be maintained at a temperature as required. Since these casting metals are generally raised and stabilized at this heat treatment temperature immediately after casting the molten metal material into these dies, such in-die heat treatment of the casting heats the casting. The processing time required to do this is reduced, for example, to about 250 minutes to about 50 minutes, so that the heat treatment of these castings follows the casting of the molten metal material into these dies, This can be done in a relatively short time. Increasing the die temperature to the heat treatment temperature for heat treating these castings further increases the decomposition and combustion of the combustible organic binder of these sand cores and / or sand molds (if used) Further shorten the time required for the heat treatment of the casting process and the removal and regeneration of the sand core and sand mold.
[0041]
Following the heat treatment of the castings in their dies in the heat treatment station 62, these castings are typically removed from the dies and optionally complete the heat treatment of the castings. In order to remove the sand core and regenerate the sand material of that core as much as possible, it can be moved to an additional heat treatment station. These castings are then moved to a quenching station 100 that quenches and cools the casting. Alternatively, as shown in FIG. 4, these castings can be removed from their dies and moved directly to this quenching station. The quench station 100 typically includes a quench tank having a cooling fluid (eg, water, or other known cooling material), which also has a series of nozzles shown at 101 in FIG. These nozzles may include a chamber that applies a cooling fluid (eg, air or water) to these castings. This quenching can also be done in a continuous attached quenching facility, which allows the cycle time and heat fluctuations to solidify and process the cast molten metal material in these dies to be minimized, Close to this casting station.
[0042]
After the heat treatment and sand removal of these castings has been completed, the castings can be removed from these dies and then immersed in the quenching tank of this quenching station to cool the castings before further processing. , And the sand removed from the casting can then be regenerated for later reuse. In addition, it is also possible to move these dies directly from this casting station to the quenching station, as indicated by the dashed lines in FIG. For example, if the dies from this casting station are heated to a heat treatment temperature at or adjacent to the casting station to heat treat these castings, these dies can then be moved directly to this quenching station.
[0043]
Thus, the present invention eliminates or reduces the need for further heat treatment of the castings once removed from these dies, which are heated to provide solution heating time while in the dies, and required quenching. Cooled to effect, the heat treatment time required to form the metal casting is significantly shortened. The present invention further enables the sand cores in the castings to be more effectively or augmented by directing fluid flow to these castings at pre-set locations, allowing heat treatment, decomposition and removal. And these locations correspond to the known orientation or alignment of the casting and / or die and the casting therein as the die and casting pass through the heat treatment station.
[0044]
While the invention has been described above in connection with a preferred embodiment, various additions, improvements and modifications may be made to the invention without departing from the spirit and scope of the invention as set forth in the claims below. Those skilled in the art will understand that this can be done.
[Brief description of the drawings]
FIG. 1 is a schematic view of a first embodiment of the present invention.
FIG. 2 is a side elevational view illustrating the introduction of molten metal into a die.
FIG. 3 is a perspective view illustrating the positioning of a casting within a saddle.
FIG. 4 is a schematic view of still another embodiment of the present invention for heat treatment in a die in a sand core removing process.
FIGS. 5A-B are side elevation views illustrating the movement of the air nozzle to various application positions around the die for in-die heat treatment. FIGS.
FIG. 6 is a side elevation view schematically illustrating an alternative embodiment of a heating chamber for in-die heat treatment of a casting.
FIG. 7 is a side elevation view schematically illustrating another alternative embodiment of a heating chamber for in-die heat treatment of a casting.
8A-B are side elevational views schematically illustrating yet another alternative embodiment of a heating chamber for in-die heat treatment of a casting.

Claims (30)

A method of processing a casting of a known metal, the method comprising the following steps:
Casting metal into a die in a molten state;
Holding the metal in the die for a time sufficient to at least partially solidify the metal to form a casting having a core and core access openings therein;
Placing the casting in an aligned position such that at least a plurality of the core access openings are aligned in a known position aligned with a plurality of nozzles; and fluid flow from the nozzles in the core access openings or Removing the core from the casting towards it;
Aligning at least a plurality of the core access openings and a plurality of second nozzles; and directing fluid from the plurality of second nozzles into or into the core access openings. A method of processing a casting of a known metal, the method comprising the following steps:
Casting metal into a die in a molten state;
Holding the metal in the die for a time sufficient to at least partially solidify the metal to form a casting having a core and core access openings therein;
Installing the casting in an aligned position such that at least a plurality of the core access openings are oriented at a known position aligned with a plurality of nozzles;
Directing fluid flow from the nozzle into or into the core access opening; removing the core from the casting; and placing the casting in an aligned position from the die before the casting. A method comprising the step of removing   Placing the casting in an alignment position includes positioning the casting in a first position with the x-axis, y-axis, and z-axis of the casting in a known first orientation; The method of claim 2, wherein the at least a plurality of core access openings are aligned with the plurality of nozzles. A method of processing a casting of a known metal, the method comprising the following steps:
Casting metal into a die in a molten state;
Holding the metal in the die for a time sufficient to at least partially solidify the metal to form a casting having a core and core access openings therein;
Placing the casting in an aligned position such that at least a plurality of the core access openings are aligned in a known position aligned with a plurality of nozzles; and fluid flow from the nozzles in the core access openings or Removing the core from the casting towards it;
Removing the casting from the die prior to installing the casting in an aligned position;
Placing the casting in a first position with the x-axis, y-axis and z-axis of the casting in a known first orientation so that at least a plurality of core access openings are aligned with a plurality of first nozzles; ;
Directing fluid flow from the plurality of first nozzles to the core access opening;
The casting with the x-axis, y-axis and z-axis of the casting in a known second orientation different from the first orientation so that at least a plurality of core access openings are aligned with a plurality of second nozzles. At a second location; and directing fluid flow from the plurality of second nozzles to the core access opening. A method of processing a casting of a known metal, the method comprising the following steps:
Casting metal into a die in a molten state;
Holding the metal in the die for a time sufficient to at least partially solidify the metal to form a casting having a core and core access openings therein;
Placing the casting in an aligned position such that at least a plurality of the core access openings are aligned in a known position aligned with a plurality of nozzles; and fluid flow from the nozzles in the core access openings or Removing the core from the casting towards it;
Placing the casting in a first casting position with the x, y and z axes of the casting in a known orientation;
Moving the plurality of nozzles to a first nozzle position in alignment with at least a plurality of core access openings; and moving at least a portion of the plurality of nozzles to a second nozzle position, wherein the plurality Aligning the portion of the nozzle with at least a plurality of second core access openings;
Including the method. A method of processing a casting of a known metal, the method comprising the following steps:
Casting metal into a die in a molten state;
Holding the metal in the die for a time sufficient to at least partially solidify the metal to form a casting having a core and core access openings therein;
Placing the casting in an aligned position such that at least a plurality of the core access openings are aligned in a known position aligned with a plurality of nozzles; and fluid flow from the nozzles in the core access openings or Removing the core from the casting towards it;
Moving the casting from the die to a saddle; and positioning the casting on the saddle such that the x, y and z coordinates of the casting are known;
Including the method. A method of treating a metal casting, the method comprising the following steps:
Providing a die with a cast core;
Preheating the die to a temperature sufficient to at least partially heat treat the metal of the casting;
Casting metal into the die in a molten state, forming a casting having a casting core therein, and forming a core access opening;
Heat treating at least partially the casting in the die; and removing the core from the casting;
Including the method. Further comprising aligning a plurality of the core access openings in the casting with a plurality of first nozzles; and directing a fluid flow from the plurality of first nozzles toward the core access openings. The method of claim 7. And aligning a plurality of the core access openings in the casting with a plurality of second nozzles; and directing a fluid flow from the plurality of second nozzles toward the core access openings. The method according to claim 8.   Aligning the core access opening with a plurality of first nozzles includes positioning the casting in a first position with the x, y and z coordinates of the casting being in a known first orientation. 10. The method of claim 9, wherein at least a plurality of core access openings are aligned with a plurality of first nozzles. Further removing the casting from the die;
Aligning the casting in a first position so that the x-axis, y-axis and z-axis of the casting are oriented in a known first orientation with at least a plurality of core access openings aligned with a plurality of first nozzles Positioning step;
Applying fluid to the casting using the plurality of first nozzles to at least partially remove the core from the casting;
Orienting the x-axis, y-axis and z-axis of the casting with a known second orientation different from the first orientation, and aligning at least a plurality of core access openings with a plurality of second nozzles; 9. The method of claim 8, comprising positioning a casting in a second position; and applying fluid to the casting using the plurality of second nozzles. The step of at least partially heat treating the casting includes the following:
Maintaining the die and casting in a known position;
Moving the plurality of nozzles to a first nozzle position about the die;
Applying heat to the die using the nozzle to at least partially remove the core from the casting;
Moving at least a portion of the plurality of nozzles to a second nozzle position; and using the nozzle, further heat is applied to the die at the second nozzle position to place the casting in the die. A further heat treatment step,
The method of claim 7 comprising:   The method of claim 7, wherein the metal comprises aluminum and the preheating step comprises heating the die to a temperature in the range of 400-600C.   8. The step of at least partially heat treating the casting comprises maintaining the temperature of the die at a temperature sufficient to at least partially heat the metal of the casting. the method of.   8. The method of claim 7, further comprising moving the casting through a plurality of nozzle stations, wherein each station comprises a plurality of nozzles.   The method of claim 7, wherein the core is formed from sand and further includes regenerating the sand of the core when removing the core from the casting.   8. The method of claim 7, further comprising quenching the casting. A system for producing a casting from molten metal, the system comprising:
A series of dies in which molten metal is received to define and form the casting;
A series of saddles, wherein the saddles are adapted to receive the casting in a desired orientation having a known alignment position orientation; and a heat treatment station, the heat treatment station comprising: The saddle is housed for heat treatment and core removal of the casting, with the castings in their known alignment positions, wherein the heat treatment station is:
A plurality of nozzle stations, each nozzle station comprising a plurality of nozzles for applying a fluid flow to the casting to substantially remove the core from the casting; A nozzle station arranged in alignment with the known position orientation of the casting,
A heat treatment station,
A system comprising:   The nozzle stations each comprise a series of robot-operated nozzles that direct fluid flow from different locations toward the casting to substantially remove and remove the core from the casting. The system of claim 18, adapted to move around the casting between at least a first nozzle position and a second nozzle position.   A series of walls defining a casting receptacle for the saddle to guide and guide the casting to their known alignment positions having a known position orientation within the saddle, and within the casting receptacle The system of claim 19, comprising a plurality of positioning devices positioned on the surface.   The positioning device includes a guide pin, wherein the casting is formed in the die with a corresponding positioning opening, in which the guide pin causes the casting to move into the saddle. 21. The system of claim 20, wherein the system is housed to be positioned at their known alignment position.   20. The system of claim 19, wherein the die comprises a mold frame mold, the mold having a heating source for preheating the die and at least partially heat treating the casting.   The system of claim 19, further comprising a quenching station that quenches the casting. A system for producing a metal casting, the system comprising:
A die, in which a metal material is received to form the casting;
A heat treatment station, the heat treatment station comprising a heat treatment chamber, wherein the die is subjected to application of heat to at least partially heat treat the casting in the die. ,
And wherein the heat treatment station comprises means for heating the die to a temperature sufficient to at least partially heat treat the casting therein. The heating means comprises at least one nozzle station, the nozzle station being located along the heat treatment station, and at least one first mounted aligned with a series of die access openings. Having a nozzle and the die access opening formed in the die to apply a fluid medium to the die to heat the die and remove the core material of the core in the casting are the system of claim 2 4.   25. The system of claim 24, wherein the heating means comprises a radiant energy source, the radiant energy source being attached to the heating chamber to direct radiant energy to the die.   25. A system according to claim 24, wherein the heating means comprises an inductive energy source, the inductive energy source being mounted in the heating chamber for transferring inductive energy to the die.   The heating means comprises an oxygen chamber, and the oxygen chamber directs an oxygen flow through the die so as to react and burn with a binder material to increase the temperature of the casting in the die. 25. The system of claim 24, located along a heat treatment station.   26. The system of claim 25, wherein the heating means further comprises an energy source, the energy source being located in the heating chamber for applying energy to the die to heat the die from the inside. .   25. The system of claim 24, further comprising a quench station for quenching the heat treated casting.

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