Title of Invention

MOLD-TRAVELING CONTINUOUS GRAVITATIONAL CASTING LINE ASSEMBLY

Abstract

A mold-travelling continuous gravitational casting line assembly comprises a plurality of conveying apparatus such as powered roller conveyers (2). A plurality of molds (21-26) placed on the conveyors are successively moved. The conveying apparatus are provided with a cast pick-up apparatus (1), an incline casting apparatus (4), a cast solidifying/cooling apparatus (7), and a mold preheating/cooling apparatus (10) disposes independently from each other A mold loading/unloading apparatus (9) independent from the conveyors allows quick replacement of the molds without stopping the casting operations A cover provided in the cast preheating/cooling apparatus (10) improves air flow for more efficient preheating or cooling. The cast pick-up apparatus (1) automatically moves the cast to an unloading table.

Full Text

TECHNICAL FIELD The present invention relates to a mold-traveling continuous gravitational casting line assembly ,and more specifically to a mold-traveling continuous gravitational casting line assembly in which a plurality of molds are moved by a conveying apparatus BACKGROUND OF THE INVENTION A prior art mold-traveling continuous gravitational casting line assembly (hereinafter may be called the facility for simplicity) comprises a casting machine fixed with a mold for performing a complete cycle of casting operations Another prior art facility comprises a circular turntable disposed with a plurality of casting machines fixed with a mold The turntable is turned so as to perform cycles of casting operations Further, for small pieces of cast, molds are moved by cylinder strokes of a mold conveying apparatus so that a single casting machine can cast a certain fixed number of molds Documents related to the facility of this kind includes (1) Japanese Patent Laid-Open No 4-66256 disclosing a method for casting a piece having a bottom, and (2) Japanese Patent Laid-Open No 64-34572 disclosing a full-mode casting apparatus -1A- Inventions described in these technical documents use a line of mold transporting system (a mold conveying apparatus) disposed with a large number of molds and stations for controlling these molds such as mold temperature controlling station, molten metal pouring station, cooling station, and mold unfolding station. However, the prior art facilities have the following problems: Specifically, in the arrangement where the casting machine is fixed with a mold, the casting machine is fixed on the ground. As a result, operation efficiency becomes dependent on the size of cast, core-setting operation, and degrees of automation in molten metal pouring and cast pick-up operations. For these limitations, a casting worker can only operate 2 or 3 machines, and therefore productivity is low. The invention disclosed in the document (1) is a continuous casting facility in which molds are moved by cylinder strokes of the mold conveying apparatus. According to this facility, only one casting machine is needed since the molds are pushed into the casting machine by the mold conveying apparatus equipped with a cylinder. As a result investment in facility and equipment can be reduced. On the other hand it is difficult for the cylinder-stroke of the mold conveying apparatus to control a plurality of molds simultaneously, and therefore the number of molds in the casting line is inevitably limited. Further, a stroke length of the cylinder for example limits the size of the operable cast, making the facility unsuitable to -2- produce a wide range of products from a small piece to a large one. The invention disclosed in the document (2) uses the circular turntable disposed with a plurality of casting machines fixed with a mold. According to this arrangement the turntable is turned for decentralized operations of picking up a cast, setting a core, pouring molten metal and so on. Work efficiency depends on the size of casting machine, cast solidifying/cooling time, and so on. A casting worker can operate 4 to 6 machines, resulting in an improved productivity On the other hand it becomes difficult to change molds flexibly to changing schedule of production, which can even decrease the productivity or rate of operation per casting machine Especially, the casting operation must be stopped when the molds are changed, which directly decreases productivity and the rate of operation. Another problem is an increased investment in facility and equipment because the casting machine is required for each mold DISCLOSURE OF THE INVENTION It is therefore an object of the present invention to provide a mold-traveling continuous gravitational casting facility which can decrease investment in facility and equipment, increase productivity and rate of operation, as well as capable of producing a wide range of products from small through large pieces According to a first aspect of the present invention, there -3- is provided a mold-travelling continuous gravitational casting line assembly comprising a plurality of conveying apparatus arranged in a substantially rectangular shape, the plurality of conveying apparatus moving a plurality of molds for continuous gravitational casting through successive pouring of molten metal into the molds wherein there are provided a cast pick-up apparatus, a casting apparatus, a cast solidifying/cooling apparatus, and a downwardly-opening mold preheating/cooling apparatus having a burner, fan and a ventilating path , characterized in that each of the above apparatus is provided in the conveying apparatus independently from each other for decentralized operation of removing a cast, setting a core, pouring molten metal, casting, cooling for cast solidification, preheating and cooling, in a cycle of casting step ; and in that there is provided a mold loading/unloading apparatus independent from the conveying apparatus for selectively handling different kinds of molds and casts having different cooling/solidifying time due to the shape and size of the cast, thereby allowing quick replacement of the molds without interrupting the casting operations According to a preferred embodiment, the conveying apparatus is a powered roller conveyer unit The present invention also provides a mold-travelling continuous gravitational casting line assembly comprising a loop of casting line and a plurality of molds disposed therein for simultaneous operations in different steps of casting to the molds accompanied by -4- successive travelling of the molds, and for placement or removal of the molds to or from the casting line without interrupting the casting operations wherein the preheating/ cooling apparatus provided in the casting line assembly for preheating or cooling the molds has a cover enclosing an upper surface and two side surfaces of the preheating/cooling apparatus, a ventilating path for discharging air from inside the cover, and a fan for sucking air from the cover into the ventilating path The present invention also provides a mold-travelling continuous gravitational casting line assembly comprising a loop of casting line and a plurality of molds disposed therein for simultaneous operations in different steps of casting to the molds accompanied by successive travelling of the molds, and for placement or removal of the molds to or from the casting line without interrupting the casting operations wherein the cast pick-up apparatus provided in the casting line assembly for removal of casts from the molds has a pick-up table for a worker to remove core-forming sand from the cast , a cast-opening/core-setting apparatus for opening an upper half of the mold, holding the cast, and then turning , a turntable for receiving the cast from the cast-opening/core-setting apparatus and then carrying the cast to a predetermined location , and a sliding guide for carrying the cast from the turntable to the pick-up table -5- According to the present invention, the molds are placed on the conveying apparatus comprising a unit of powered roller conveyer. Using electric control of the conveying apparatus, the plurality of molds are brought to respective stations. In such a way, steps of casting operations can be performed at dispersed locations respectively by specialized apparatuses such as the cast pick-up/core-setting step (performed by the cast pick-up apparatus), the molten metal pouring step (by the casting apparatus), the solidifying/cooling step (by the cast solidifying/cooling apparatus), and the mold preheating/cooling step (by the mold preheating/cooling unit) . With this arrangement, a continuous steps of casting i.e. setting of the core (into the mold) , pouring the molten metal, solidifying/cooling the cast, and picking up the cast can be performed simultaneously and separately, resulting in increased productivity. Further, the mold loading/unloading apparatus is provided between the cast solidifying/cooling station and the mold preheating/cooling station. This allows placement of a new mold after the new mold has been applied with facing and preheated elsewhere . Likewise, an existing mold in the casting line, which is not placed with a core or poured with molten metal, can be removed from the line without interrupting other operations. Thus, it becomes possible to eliminate time for changing the molds, which has long been a challenge. Further, a mold mounting plates is used as a guide for positioning and transporting the molds. The electrically -6- controlled roller conveyer unit is sized to the mold mounting plate, and a plurality of the roller conveyer units are disposed in each of the cast solidifying/cooling unit and the mold preheating/cooling unit. With this arrangement, the molds can be stopped at any of the conveyer units, making possible to flexibly control the number of molds on the line depending on the change in scheduled volume of production, shape and size of the mold or cast. As a result, it becomes possible to improve the rate of operation. Still further, the preheating/cooling apparatus is equipped with the burner. The upper surface and side surfaces of the preheating/cooling unit is enclosed by the cover. The cover is provided with a ventilating path and the ventilating path is provided with a fan. These arrangements make possible to quickly heat during the preheating step as well as to quickly cool by air during the cooling step, leading to increased operation efficiency. Further, since the cover is opened downwardly, air can come in freely, moisture can be removed quickly, and thus the molds are quickly preheated or cooled. Still further, the use of air contributes low cost operation and is nonpolluting to the environment. Still further, the turntable receives the cast from the cast-opening/core-setting unit, and carries the cast to a predetermined location. Then, the sliding guide carries the cast to the pick-up table. This arrangement provides automatic transportation of the cast to the pick-up table for increased operability. -7- Other features and advantages of the present invention will become cclearer from the following description of the embodiment made with reference to the accompanied drawings BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS Fig 1 shows an overall layout of a mold-traveling continuous gravitational casting line facility as an embodiment of the present invention Fig 2A is a plan view of a powered roller conveyer unit provided in the mold-traveling continuous gravitational casting line facility in Fig 1 Fig 2B is a side view of a powered roller conveyer unit provided in the mold-traveling continuous gravitational casting line facility in Fig 1 Fig 3 is an enlarged side view of a mold used in the mold-traveling continuous gravitational casting line facility in Fig 1 Fig 4A is a plan view of a cast pick-up apparatus provided in the mold-traveling continuous gravitational casting line facility in Fig 1 Fig 4B is a side view of the cast pick-up apparatus provided in the mold-traveling continuous gravitational casting line facility in Fig 1 Fig 5A is a plan view of a mold preheating/cooling apparatus provided in the mold-traveling continuous gravitational casting line facility in Fig 1 -8- BEST MODE FOR CARRYING OUT THE INVENTION As shown in Fig 1, a mold-traveling continuous gravitational casting line facility according to the present embodiment comprises a cast pick-up apparatus 1 provided in a powered roller conveyer unit 2, an incline-pouring casting apparatus 4 provided in another powered roller conveyer unit 2, a teeming robot 5, a melting furnace 6, a cast solidifying/cooling apparatus provided with a plurality of powered roller conveyer units 2, a mold conveying apparatus 8 provided in another powered roller conveyer unit 2, a mold loading/unloading apparatus 9 provided in another powered roller conveyer unit 2, a mold preheating/cooling apparatus 10 provided with a plurality of powered roller conveyer units 2, and a mold conveying apparatus 11 provided in another powered roller conveyer unit 2 As shown in Figs 2A and 2B, the powered roller conveyer unit 2 (see Fig 1) mainly comprises an electric driving motor 2a, sprockets 2b, roller conveyer sprockets 2c, conveyer rollers 2d, and chains 2e, 2f This powered roller conveyer unit 2 is sized to a standardized upper mounting plate and a standardized lower mounting plate of the mold The upper and lower mounting plates are used as guides for positioning and moving the mold Each of the conveyer rollers are driven by the drive motor 2a via the sprockets 2b, 2c and the chains 2e, 2f As shown in Fig 3, a mold 21 mainly comprises an upper half 21a, an upper mounting plate 21b, an upper pushing plate 21c, a lower half 21d, a lower mounting plate 21 e, and a lower -9- pushing plate 21f. The mold 21 is movable on the powered roller conveyer units 2 for tentative fixation by hydraulic clamping to a relevant apparatus for receiving a specific step of casting operation. For this purpose, an upper surface of the upper mounting plate 21b and the lower surface of the lower mounting plate 21e are flat and parallel to each other. Further, the upper mounting plate 21b and the lower mounting plate 21e are standardized so that the plates of the identical standard are used for a variety of molds. It should be noted that the other molds 22, 23, 24, 25 and 26 have the same arrangement as for the mold 21. As shown in Figs. 4A and 4B, the cast pick-up apparatus 1 is provided with an electric motor la. This motor la causes an arm lb and an arm 3a of a mold-opening/core-setting apparatus 3 to swing in opposite directions to each other. Further, the motor la turns a table 1d attached to the arm lb via a chain lc. The turntable 1d abuts on an unloading table le. The unloading table le is provided above a space where a truck If can move in and out. A sliding guide lg is provided above the turntable 1d and the unloading table le. When a cast is delivered to the turntable 1d, the guide lg moves the cast to the unloading table le. The unloading table le is formed like a drain board for example so that sand as a core forming material falls through the unloading table le for collection by the truck 1f. As shown in Figs. 5a and 5b, the mold preheating/cooling apparatus 10 has two side surfaces and an upper surface each 10 enclosed by a cover 10a. The cover 10a has side surfaces provided with a plurality of burners 10b. The burners 10b heat an inside of the cover 10a during a preheating step. The cover 10a has an upper surface provided with an exhaust pipe 10c. The exhaust pipe 10c provides a ventilating path for the air inside the cover 10a. The upper surface of the cover 10a is also provided with a fan 10d. This fan 10d communicates with the ventilating path provided by the exhaust pipe 10c for sucking the air from inside the cover 10a to the ventilating path. When the mold 21 shown in Fig. 1 comes to the cast pick-up apparatus 1, the upper half 21a of the mold 21 is opened upwardly by the mold-opening/core-setting apparatus 3. Then, the cast pick-up apparatus 10 removes the cast. Specifically, the cast inside the mold 21 is moved from the mold-opening/core-setting apparatus 3 to the turntable 1d by a swivel movement of the arms lb and 3a. The movement of the arm 1b is accompanied by synchronized turning of the turntable 1d so that the turntable 1d keeps an appropriate attitude. When the arm lb finishes the movement, the turntable 1d comes back to the original position, whereupon the sliding guide lg pushes the cast on the turntable 1d to the unloading table le. Once the cast reaches the unloading table le, then a worker removes part of sand used as the core from the cast. During this unloading step, another worker sets a core into the lower half 21d of the mold 21, and then closes and clamps the mold. During the above steps, the mold 22 stays in the incline casting apparatus 4, where a pouring gate of the mold 22 receives -11- molten metal poured by the teeming robot 5. The incline casting apparatus 4 has an incline pouring mechanism (umllustrated) which fills the mold 22 with the molten metal. The mold 23 stays in the cast solidifying/cooling apparatus 7, where the molten metal filled in the mold 23 is cooled by the cast solidifying/cooking apparatus 7 for quick hardening of the cast. The mold 24 stays on the roller conveyer unit 2 in the mold conveying apparatus 8. The mold 24 is moved by transportation of the powered roller conveyer unit 2, specifically from a position facing the cast solidifying/cooling apparatus 7 to a position facing the mold loading/unloading apparatus 9 and mold preheating/cooling apparatus 10. The mold 25 stays on the mold preheating/cooling apparatus 10. The mold 25 is preheated or cooled by the mold preheating/cooling apparatus 10. The mold preheating/cooling apparatus 10 has the upper surface and side surfaces covered by the cover 10a. Therefore, the mold 25 can be efficiently heated by the burners 10b during the preheating step. On the other hand the mold 25 can be efficiently cooled by air during the cooling step since the fan 10d discharges air through the mold preheating/cooling apparatus 10 to the exhaust pipe. The mold 26 stays on the powered roller conveyer unit 2 in the mold conveying apparatus 11. The mold 26 is moved by transportation of the powered roller conveyer unit 2, specifically from a position facing the mold preheating/cooling apparatus 10 to a position facing the cast pick-up apparatus -12- 1. Each of the molds 21 through 26 is successively moved by the powered roller conveyer units 2 in a direction of arrow A in Fig. 1. This makes a cycle of visiting each of the apparatuses, making all of the molds 21 through 2 6 receive different operations simultaneously within respective apparatuses, achieving a successive production of castings. When a new mold 31 is added to the casting line, the mold 31 is applied with facing and preheated elsewhere in advance. Then, the mold 31 is placed onto the powered roller conveyer unit 2 of the mold loading/unloading apparatus 9. The mold 31 is then moved from the powered roller conveyer unit 2 of the mold loading/unloading apparatus 9 to the powered roller conveyer unit 2 of the mold conveying apparatus 8. This operation interrupts none of the other operations being performed to the other molds 21 through 26, making possible to place the mold 31 in the mold preheating/cooling apparatus 10. When removing the mold 21 for example from the casting line, the core placement is not performed to the mold 21, and the teeming robot 5 and the incline casting apparatus 4 is run idle for the mold 21. In the mean time the mold 21 is moved from the cast pick-up apparatus 1 to the mold conveying apparatus 8. The mold 21 is then moved from the powered roller conveyer unit 2 of the mold conveying apparatus 8 to the powered roller conveyer unit 2 of the mold loading/unloading apparatus 9. Through these operations the mold 21 can be removed from the casting line without disturbing the casting operations to the 13 other molds 22 through 26. Any of the other molds 22 through 26 can of course be removed according to the same procedure. Specifically, the casting operation can be performed continuously regardless of the number of molds present in the casting line. Further, presence of molds which are not used for the casting operation in the line will not interrupt the continuous casting operation. As has been described above, a plurality of molds 21 through 26 are disposed in the casting line. These molds 21 through 2 6 are moved in the direction shown by the arrow in Fig. 1. With this arrangement, different steps of casting operation can be performed simultaneously in succession at dispersed stations of operation. Thus, a grater productivity as compared to that of the prior art casting lines can be achieved. Further, the mold loading/unloading apparatus 9 allows placement and removal of any mold without interrupting the casting operations. Thus, it becomes possible to realize a facility having a high rate of operation without requiring time for changing molds. Further, each of the cast solidifying/cooling apparatus 7 and the mold preheating/cooling apparatus 10 is provided with a plurality of powered roller conveyer units 2. Thus, each of these powered roller conveyer units 2 can haul a mold, making possible to change the number of molds in the casting line for economy according to the volume of production. Still further, idle molds placed in the line but not used for the casting operation does not affect the continuous casting -14- operation. Thus, it becomes possible to perform the casting operation flexibly according to given situations. Still further, only a single unit of expensive incline casting apparatus 4 and the teeming robot 5 may be installed, making possible to reduce investment in facility and equipment. Still further, the powered roller conveyer unit 2 is sized fairly large, and standardization was made to the upper mounting plate 21b as well as to the lower mounting plate 21e which serve as guides for transporting and positioning. Thus, a variety of casts from a small piece to a large one can be produced in the same casting line. Still further, the mold preheating/cooling apparatus 10 is provided with the cover 10a opening downwardly. This helps unrestricted airflow for quick heating during the preheating step, and quick cooling by air during the cooling step. The use of air makes the system low cost and environmentally nonpolluting. -15- WE CLAIM : 1 A mold-travelling continuous gravitational casting line assembly comprising a plurality of conveying apparatus arranged in a substantially rectangular shape, the plurality of conveying apparatus moving a plurality of molds for continuous gravitational casting through successive pouring of molten metal into the molds wherein there are provided a cast pick-up apparatus, a casting apparatus, a cast solidifying/cooling apparatus, and a downwardly-opening mold preheating/cooling apparatus having a burner, fan and a ventilating path , characterized in that each of the above apparatus is provided in the conveying apparatus independently from each other for decentralized operation of removing a cast, setting a core, pouring molten metal, casting, cooling for cast solidification, preheating and cooling, in a cycle of casting step, and in that there is provided a mold loading/unloading apparatus independent from the conveying apparatus for selectively handling different kinds of molds and casts having different cooling/solidifying time due to the shape and size of the cast, thereby allowing quick replacement of the molds without interrupting the casting operations. -16- 2 The mold-travelling continuous gravitational casting line assembly as claimed in claim 1, wherein the conveying apparatus is a powered roller conveyer 3 A mold-travelling continuous gravitational casting line assembly comprising a loop of casting line and a plurality of molds disposed therein for simultaneous operations in different steps of casting to the molds accompanied by successive travelling of the molds, and for placement or removal of the molds to or from the casting line without interrupting the casting operations • wherein the preheating/cooling apparatus provided in the casting line assembly for preheating or cooling the molds has a cover enclosing an upper surface and two side surfaces of the preheating/cooling apparatus, a ventilating path for discharging air from inside the cover, and a fan for sucking air from the cover into the ventilating path 4 A mold-travelling continuous gravitational casting line assembly comprising a loop of casting line and a plurality of molds disposed therein for simultaneous operations in different steps of casting to the molds accompanied by successive travelling of the molds, and for placement or removal of the molds to or from the casting line without interrupting the casting operations wherein the cast pick-up apparatus provided in the casting line assembly for removal of casts from the molds has a pick-up table for a worker to remove -17- core-forming sand from the cast , a cast-opening/core-setting apparatus for opening an upper half of the mold, holding the cast, and then turning a turntable for receiving the cast from the cast-opening/core-setting apparatus and then carrying the cast to a predetermined location , and a sliding guide for carrying the cast from the turntable to the pick-up table 5 A mold-travelling continuous gravitational casting line assembly substantially as herein described, particularly with reference to and as illustrated in the accompanying drawings -18-

Documents:

00563-cal-1999-abstract.pdf

00563-cal-1999-assignment.pdf

00563-cal-1999-claims.pdf

00563-cal-1999-correspondence-1.pdf

00563-cal-1999-correspondence-2.pdf

00563-cal-1999-correspondence-3.pdf

00563-cal-1999-description(complete).pdf

00563-cal-1999-drawings.pdf

00563-cal-1999-form-1.pdf

00563-cal-1999-form-19.pdf

00563-cal-1999-form-2.pdf

00563-cal-1999-form-3.pdf

00563-cal-1999-gpa.pdf

00563-cal-1999-letters patent.pdf

00563-cal-1999-other document.pdf

563-cal-1999-granted-abstract.pdf

563-cal-1999-granted-acceptance publication.pdf

563-cal-1999-granted-assignment.pdf

563-cal-1999-granted-claims.pdf

563-cal-1999-granted-correspondence.pdf

563-cal-1999-granted-description (complete).pdf

563-cal-1999-granted-drawings.pdf

563-cal-1999-granted-form 1.pdf

563-cal-1999-granted-form 19.pdf

563-cal-1999-granted-form 2.pdf

563-cal-1999-granted-form 3.pdf

563-cal-1999-granted-gpa.pdf

563-cal-1999-granted-letter patent.pdf

563-cal-1999-granted-reply to examination report.pdf

563-cal-1999-granted-specification.pdf