Post-teeming mold removal device and post-teeming mold removal method

Abstract

To provide a post-teeming mold removal device that is capable of solving the problem of maintenance, eliminating a limitation on the installation space, and reducing the running cost.　The present invention comprises: an electric motor; a lifting frame that can support and move up and down the lower surface of a sand mold part located inside the molding flask of a post-teeming mold; an arm member that extends in the lateral direction and swings in a virtual vertical plane with a fulcrum serving as the rotation center, a force point receiving the driving force of the electric motor, and an application point rotating on the basis of the driving force applied to the force point, the application point being located below the lifting frame; a driving force transmission mechanism that is provided between the electric motor and the force point of the arm member; a link member that extends in the vertical direction below the lifting frame and connects the application point of the arm member and the lifting frame; and a lifting restriction device that comes into contact with the outer periphery of the molding flask to restrict lifting of the molding flask when the lifting frame moves upward.

Description

Apparatus and method for removing poured mold

[0001] The present invention relates to a mold removal device and a mold removal method for removing a poured mold from a molding flask.

[0002] A conventional method for removing a poured mold from a flask is to use a cylinder device to pull the mold straight up from below, as shown in Patent Document 1. The main purpose of this method is to slowly cool the product in the mold for a certain period of time after removing it from the outside without destroying the mold as much as possible.

[0003] This method requires a large amount of power to remove the mold from the flask, so a hydraulic cylinder is generally used.

[0004] However, hydraulic cylinders require a hydraulic unit to operate and control the cylinder, and the hydraulic pump motor is often in constant operation during production, which poses a problem of high power consumption.

[0005] For this reason, in recent years, non-hydraulic cylinders have been considered and actuators are being made more electric in order to save energy by reducing power consumption.

[0006] However, when an electric motor is used, the torque generated in the rotary drive shaft when the mold is removed from the inner wall of the flask in the early stages of removal is excessive, which causes problems such as the need to increase the size of the drive system in order to increase its strength.In addition, the rotation speed of the rotary arm is slowed down due to the generation of such a large torque, which results in problems such as the removal operation taking a long time.

[0007] Therefore, the inventors proposed an invention of a poured mold removal device, as shown in Patent Document 2, which is capable of generating a large torque in the initial stage and then performing the removal operation at a high speed.

[0008] Japanese Patent Application No. 2022-132216

[0009] This invention is excellent in that it eliminates wasteful power consumption and improves work efficiency. However, the mechanism, which receives a large load during mold removal, is located directly below the lifting frame. As a result, the mechanism is subject to the casting sand falling from the sand mold being removed during mold removal, potentially causing maintenance problems such as breakdowns and wear. Furthermore, the hopper and conveyor used to collect and transport the falling sand overlap the mechanism, limiting installation space. Furthermore, there is a demand for a more compact drive source to reduce running costs.

[0010] The present invention has been made in view of the above-mentioned problems of the prior art, and its object is to provide an apparatus and a method for removing a poured mold which can solve the problems of maintenance, eliminate the restrictions on installation space, and reduce running costs.

[0011] The first aspect of the poured mold removal device of the present invention comprises an electric motor, a lifting frame that supports the underside of the sand mold portion that is inside the molding flask of the poured mold so that it can be raised and lowered, and an arm member that extends laterally and has a fulcrum that serves as the center of rotation, a force point to which the driving force of the electric motor is applied, and a point of action that rotates based on the driving force applied to the force point, the force point being located below the lifting frame and at least the force point being located at a position away from the position below the lifting frame, and that swings along an imaginary vertical plane.

[0012] The lifting frame is also provided with a drive force transmission mechanism provided between the electric motor and the force point of the arm member, a link member extending vertically below the lifting frame and connecting the force point of the arm member to the lifting frame, and an ascent restriction device that abuts against the outer periphery of the molding flask when the lifting frame is raised to restrict the ascent of the molding flask.

[0013] This allows the point of application to be located below the lifting frame, and the mechanical part, including the force point where the driving force is input, to be located away from below the lifting frame. This prevents the mechanical part from being covered with the casting sand that falls when the mold is removed, and solves maintenance problems such as wear and breakdown of the mechanical part due to sand getting caught.

[0014] In addition, the hopper and conveyor that collect and transport the falling sand can be located away from the mechanism, eliminating the problem of limited installation space. Furthermore, because the arm member is designed to work on the principle of leverage, a low-torque electric motor can be used at the point of force, making it possible to select an inexpensive electric motor, thereby reducing running costs during use.

[0015] According to the second aspect of the poured mold removal apparatus of the present invention, in the first aspect of the poured mold removal apparatus, the drive force transmission mechanism comprises a first mechanism that generates the force required to shift the sand mold portion formed in the molding flask upward from the molding flask, and a second mechanism that further retracts the sand mold portion shifted by the first mechanism upward, wherein the force generated by the first mechanism for shifting is greater than the force generated by the second mechanism for removing the sand mold portion, and the speed at which the second mechanism removes the sand mold portion is faster than the speed at which it is shifted by the first mechanism.

[0016] According to this, when a load is applied to a force point using the principle of leverage, a first mechanism is used to shift the sand mold portion formed in the flask upward from the flask, which requires a large force, and a second mechanism, which is faster, is used to remove the sand mold portion shifted by the first mechanism.

[0017] In this way, the high load region where the load is raised at a slow speed and the low load region where the load is raised at a high speed can be made to function efficiently according to the load required when removing the mold, without changing the output of the electric motor itself, which is the driving source.

[0018] According to the third aspect of the present invention, in the apparatus for removing a poured mold of the second aspect, the first mechanism is a rotating arm whose tip rotates at a predetermined radius when driven by the electric motor, and the second mechanism includes a first link member whose base end is connected to the tip of the rotating arm and whose tip rotates at a radius larger than the radius of rotation of the rotating arm.

[0019] With this, the high load range for slow lifting is achieved by rotating the rotary arm and winding up the first link member, and the low load range for fast lifting is achieved by winding up the point of force of the arm member with the first link member that is wound up on the rotary arm and has a tip end with a larger radius of rotation than the rotary arm.

[0020] According to a fourth aspect of the present invention, in the apparatus for removing a poured mold of the first aspect of the present invention, the arm member has the fulcrum provided between the force point and the point of action, and the fulcrum comprises two fulcrums, a first fulcrum and a second fulcrum located closer to the force point than the first fulcrum, the first fulcrum being used when the sand mold portion formed in the molding flask is shifted upward from the molding flask, and the second fulcrum being used when the shifted sand mold portion is further removed upward.

[0021] According to this, when the same arm member is used and the first fulcrum is used, the point of application is closer and the point of force is farther away compared to the second fulcrum, so that, according to the principle of leverage, a large force is more likely to be generated at the point of application, even though the travel distance is shorter.When the second fulcrum is used, a large force is less likely to be generated at the point of application, but a larger travel distance can be ensured, allowing for a faster travel speed.

[0022] According to the fifth aspect of the present invention, in the apparatus for removing a poured mold of the fourth aspect of the present invention, the first fulcrum and the second fulcrum are each provided with a roller having a rotation axis extending in a direction perpendicular to the plane in which the arm member swings, and a receiving part having a crescent-shaped recess corresponding to the outer periphery of the roller, for removably supporting the outer periphery of the roller in the vertical direction.

[0023] With this, even when the first fulcrum and the second fulcrum each serve as a fulcrum, the freely rotating roller and the receiving portion corresponding to the shape of the roller prevent the center of rotation of the arm member from becoming misaligned.The first fulcrum and the second fulcrum can be easily and smoothly switched between states where such misalignment does not occur.

[0024] According to the sixth aspect of the poured mold removal apparatus of the present invention, in the poured mold removal apparatus of the fifth aspect of the present invention, a roller guide is provided at the first fulcrum to guide the trajectory of the roller that has come off the receiving portion.

[0025] According to this, when the effective fulcrum switches to the second fulcrum, the roller that was the first fulcrum moves away from the receiving part, but the trajectory of movement is regulated by the roller guide, so that stable and safe movement can be achieved.

[0026] According to a seventh aspect of the poured mold extractor of the present invention, in the apparatus of the third aspect of the present invention, the rotating arm, the arm member, and the link member move on the same plane, which allows the rotating arm, the arm member, and the link member to be arranged compactly, thereby saving space.

[0027] The poured mold removal method of the eighth aspect of the present invention includes a shifting step in which the poured mold removal apparatus of the first aspect of the present invention is used to relatively shift the sand mold portion in the vertical direction to remove it from the molding flask, and a removal step in which the sand mold portion shifted in the shifting step is removed with a force smaller than that used in the shifting step and at a speed greater than that used in the shifting step.

[0028] This allows for a large force to be applied to the force point using the principle of leverage in the process of shifting the sand mold portion formed in the flask upward from the flask. And, in the process of removing the shifted sand mold portion, a high speed can be achieved. In this way, efficient work can be performed in accordance with the work process.

[0029] 1 is a schematic diagram, partially in cross section, seen from the front side of a first embodiment of the apparatus for removing poured molds of the present invention. It is a cross-sectional view taken along the line II-II in FIG. 1. It is a cross-sectional view taken along the line III-III in FIG. 1. It is a cross-sectional view taken along the line IV-IV in FIG. 1. It is a cross-sectional view taken along the line V-V in FIG. 1. It is a cross-sectional view taken along the line VI-VI in FIG. 1. It shows a state in which the rotating arm has been rotated 90 degrees from the initial position. It shows a state in which the rotating arm has been rotated 180 degrees from the initial position. It shows a state in which the rotating arm has been rotated 270 degrees from the initial position. It shows a state in which the rotating arm has been rotated 360 degrees from the initial position. It is a schematic diagram, partially in cross section, seen from the front side of a second embodiment of the apparatus for removing poured molds of the present invention. It is a cross-sectional view taken along the line XII-XII in FIG. 11. It is a cross-sectional view taken along the line XIII-XIII in FIG. 11. It is a cross-sectional view taken along the line XIV-XIV in FIG. 13. It is a cross-sectional view taken along the line XV-XV in FIG. 11. It is a cross-sectional view taken along the line XVI-XVI in FIG. 11. It is a cross-sectional view taken along the line XVII-XVII in FIG. 11. 10 is a view showing the state where the rotary arm is rotated to switch the fulcrum from the first fulcrum to the second fulcrum, and FIG. 11 is a view showing the state where the lifting frame is raised to the lift end and the poured mold is removed.

[0030] (First embodiment) A first embodiment of the poured mold removing apparatus according to the present invention will be described below with reference to Figs.

[0031] 1, the horizontal direction extending from side to side is referred to as the X-axis direction, and the horizontal direction perpendicular to the X-axis direction is referred to as the Y-axis direction. If a virtual center line is considered for a tangible object, the side closer to the center line is referred to as the inside, and the side farther from the center line is referred to as the outside.

[0032] As shown in FIG. 1 , the poured mold removal device 1 in the first embodiment includes an electric motor 2, a drive force transmission mechanism 3, an arm member 4, a link member 5, a lifting frame 6, and a lifting restriction device 7.

[0033] The poured mold removal device 1 is installed so that part of its lower part is housed in a trench TRC dug in the floor FL. Most of the poured mold removal device 1 is installed on a base frame BF that is horizontally installed across the upper end of the trench TRC on the opposite side in the X-axis direction.

[0034] 1, the base frame BF is made of, for example, iron and has a rectangular frame shape with long sides BF1 that face each other in the Y-axis direction and short sides BF2 that face each other in the X-axis direction. Four horizontal crosspieces BF3 are disposed between the facing long sides BF1 so as to extend in the Y-axis direction. The long sides BF1 and the horizontal crosspieces BF3 are formed so that their upper and lower end surfaces are at the same height.

[0035] Two horizontal members BF4 extending in the X-axis direction are provided parallel to each other between the rightmost horizontal member BF3 and the right short side member BF2 in Fig. 2. The horizontal member BF4 is formed so that the long side member BF1 and the horizontal member BF3 are aligned at the same height at the top and bottom. Support legs 61 (see Fig. 1) that guide the lifting frame 6 (described later) are fixed to the top of the rectangular frame formed by the two long sides BF1 and the central horizontal member BF3.

[0036] (Electric Motor) As shown in Figure 2, two electric motors 2 are fixed to the base frame BF with their output shafts 21 facing each other. For example, a servo motor is used as the electric motor 2. When using two electric motors 2 to swing the arm member 4, it is desirable to drive one of the two electric motors as a master and the other as a slave in order to synchronously control these electric motors 2. Note that, in some cases, inverter-controlled motors can also be used as these electric motors 2.

[0037] The output shafts 21 of the two electric motors 2 are connected to a single drive rotation shaft RDS via couplings. The drive rotation shaft RDS is assembled to a pair of rotating arms 30 (described later) arranged side by side in the direction in which the drive rotation shaft RDS extends, so as to be non-rotatable relative to the rotating arms 30.

[0038] (Driving Force Transmission Mechanism) The driving force transmission mechanism 3 transmits the driving force of the electric motor 2 to the arm member 4. The driving force transmission mechanism 3 of the first embodiment includes a rotating arm 30, a first link member 31, and a second link member 32.

[0039] The rotating arm 30 is, for example, made of two oval iron plates arranged opposite each other and non-rotatable around the drive rotation shaft RDS connected to the output shafts 21 of the two electric motors 2. One end of each oval plate of the rotating arm 30 has a sharply pointed top, and the other end has a semi-disk-shaped protrusion that forms part of the first connecting part FCP.

[0040] The drive rotation shaft RDS is rotatably supported by a bearing member 205 fixed to the base frame BF and equipped with a ball bearing (see FIG. 3). The bearing members 205 are provided in pairs, sandwiching the rotation arm 30 therebetween, and one of the bearing members 205 has a protruding support arm 205a with a regulating roller 205b at its tip. The support arm 205a is provided at an angle in the direction of rotation during winding. The regulating roller 205b is provided to contact an arc-shaped portion ASP of a first link member 31 (described later) to guide the rotation of the first link member 31.

[0041] The first connecting portion FCP connects the rotating arm 30 to a first link member 31, which will be described later. As shown in Figure 3, the first connecting portion FCP of the rotating arm 30 has connecting holes FCH formed in two plates, and a pivot pin AP passes through the connecting holes FCH. The pivot pin AP passes through an upper connecting hole UFCH of the first link member 31, which will be described later, and rotatably supports the first link member 31.

[0042] 1, a locking portion LP is formed on one end of the rotating arm 30 where the top is provided, on the side in the direction of rotation when the rotating arm 30 winds up the first link member 31. The locking portion LP has a linear edge formed from the top to the base, and abuts against a locked portion LEP of the first link member 31, which will be described later. By abutting the locked portion LEP against the locking portion LP in this way, the first link member 31 can be wound up neatly onto the rotating arm 30.

[0043] The first link member 31 connects the rotary arm 30 and the second link member 32. The first link member 31 is formed of, for example, a single iron plate.

[0044] As shown in Figure 3, the first link member 31 is arranged so that the end connected to the rotating arm 30 is sandwiched between two plates of the rotating arm 30. An upper connecting hole UFCH is formed in the first connecting part FCP on the rotating arm 30 side of the first link member 31, and a bearing that rotatably supports the pivot pin AP is provided in the upper connecting hole UFCH. The distance L1 from the center of the drive rotation shaft RDS to the center of the upper connecting hole UFCH is the rotation radius of the rotating arm 30 (see Figure 8). The rotating arm 30 corresponds to the first mechanism.

[0045] The end of the first link member 31 that is connected to the rotating arm 30 side is bent along the winding direction, as shown in Figure 1. The inner periphery of the bent end of the first link member 31 is formed with a recess RC that is curved to follow the outer periphery of the drive rotation shaft RDS.

[0046] An arc-shaped portion ASP is formed on the outer peripheral edge of the first link member 31 when it is wound up. This arc-shaped portion ASP constitutes part of the circumference when it rotates around the drive rotation shaft RDS, and a regulating roller 205b formed on the bearing member 205 rolls on this arc-shaped portion ASP. The regulating roller 205b is brought into rolling contact with the arc-shaped portion ASP to guide the first link member 31 so that it rotates smoothly.

[0047] An arm AM extending linearly is formed on the side of the first link member 31 facing the second link member 32, and as shown in Figure 3, a lower connecting hole DFCH is provided at the tip of the arm AM. A connecting hole FCH is provided at the end of the second link member 32, which will be described later, facing the first link member 31. A second connecting part SCP is formed by the connecting hole FCH at the tip of the arm AM, the connecting hole FCH at the end of the second link member 32 facing the first link member 31, and the pivot pin AP that communicates with these connecting holes FCH.

[0048] The arm AM of the first link member 31 has a central portion provided with latching portions LEP protruding along the Y-axis direction on both sides of the plate material. The latching portions LEP are formed in a rectangular column shape. When the rotating arm 30 rotates, for example, 180 degrees from the initial position, it comes into contact with the latching portion LP, and the first link member 31 itself begins to rotate around the drive rotation axis RDS. The radius of rotation of the first link member 31 is the length L3 from the center of the drive rotation axis RDS to the center of the second connecting portion SCP (see FIG. 8). This L3 is the length L1 subtracted from the length L2 from the center of the first connecting portion FCP to the center of the second connecting portion SCP (see FIGS. 1 and 8).

[0049] As shown in FIGS. 1 and 3, the second link member 32 is integrally formed by connecting two plates BM bent into a boomerang shape with a short cylindrical connecting member CM.

[0050] A connecting hole FCH is formed in each lower end of the second link member 32. A third connecting part TCP is formed by the connecting holes FFCH formed at the force point PF of the arm member 4 and the pivot pin AP communicating with these connecting holes FCH. A ball bearing is provided in the connecting hole FFCH formed at the force point PF of the arm member 4, connecting the arm member 4 and the second link member 32 so as to be rotatable relative to each other.

[0051] (Arm member) As shown in Figure 1, the arm member 4 in the first embodiment has a point of action PA between a force point PF connected to the second link member 32 and a fulcrum F provided on the shaft support member BF5 at the lower end of the base frame BF.

[0052] The arm member 4 is a single, elongated plate member whose width gradually increases from both ends toward a portion in the middle corresponding to the point of application PA. By extending laterally, the arm member 4 laterally shifts the point of application PF and the fulcrum F from the link member 5 located directly below the point of application PA. Therefore, "extending laterally" in this application document means that the arm member 4 is provided so that the point of application PF and the fulcrum F provided on the arm member 4 are positioned away from directly above the link member 5.

[0053] A coupling hole FFCH is provided in a portion of the arm member 4 corresponding to the force point PF, and a coupling hole AFCH is provided in a portion of the arm member 4 corresponding to the action point PA. These coupling holes FFCH and AFCH are provided with, for example, ball bearings.

[0054] At the portion corresponding to the fulcrum F, a rotation shaft 4d integral with the arm member 4 is provided protruding on both sides in the Y-axis direction. The rotation shaft 4d is composed of a thick shaft portion at the base end and a thin shaft portion at the tip end, and the thin shaft portion is supported in a support hole BF5h provided in the shaft support member BF5 of the base frame BF. A ball bearing is provided in the support hole BF5h.

[0055] (Link Member) The link member 5 connects the application point PA of the arm member 4 with the lower part of the lifting frame 6, and transmits force so that the swinging motion of the arm member 4 becomes the upward motion of the lifting frame 6. As shown in Figure 4, the link member 5 is made up of two opposing elongated rectangular plate-like bodies 5a, which are connected with a gap between them by short cylindrical connecting members 5b provided at three locations, and the two plate-like bodies 5a form an integrated link member 5.

[0056] At the lower end of the link member 5, a lower through-hole 5c is formed through each of the two plate-like bodies 5a, and a pivot pin member SPM passes through the lower through-hole 5c. At the lower end of the link member 5, the end of the arm member 4 on the application point PA side is sandwiched between the two plate-like bodies 5a, and the link member 5 is connected so that it is held between them. At the upper end of the link member 5, an upper through-hole 5d is formed through each of the two plate-like bodies 5a, and a pivot pin member SPM passes through the upper through-hole 5d. At the upper end of the link member 5, the link member 5 is connected so that a connecting portion 63c of the lifting frame 6, which will be described later, is sandwiched between the two plate-like bodies 5a.

[0057] 4, the lifting frame 6 includes a support leg 61, a guide 62, and a lifting unit 63. The support leg 61 is fixed to the upper surface of a rectangular portion of the base frame BF formed by two long side portions BF1 and two horizontal beam portions BF3, for example, with bolts and nuts (not shown) (see FIGS. 4 and 6).

[0058] 4 and 6, the support leg 61 is made of, for example, iron, and is formed in a square cylindrical shape, with a top plate 61a having a rectangular through-hole 61b at the upper end. The through-hole 61b is formed so that the link member 5 can be loosely inserted therein. On both sides of the through-hole 61b aligned in the Y-axis direction, cylindrical portions 62a of the guide portion 62, which will be described later, are passed through and fixed in pair.

[0059] The support leg 61 has four sides surrounded by a cover member 63d of the lifting unit 63, which will be described later.

[0060] (Guide Portion) The guide portion 62 guides the vertical movement of the lifting portion 63. As shown in Fig. 4, the guide portion 62 includes a cylindrical portion 62a and a guide rod 62b.

[0061] The tubular portions 62a are made of, for example, iron and formed into a cylindrical shape, and are arranged side by side along the Y-axis direction on both sides of the through-hole 61b as described above. The lower portion of each tubular portion 62a is inserted into the top plate 61a, and a flange portion 62a1 is provided around the upper outer periphery of the inserted portion. A guide rod 62b is slidably inserted into the tubular portion 62a. The guide rod 62b is made of, for example, iron and formed into a rod shape with a circular cross section, and its tip is embedded and fixed in the support plate 63b of the lifting unit 63.

[0062] 4, the lifting unit 63 includes a lifting plate 63a, a support plate 63b, a connecting portion 63c, and a cover member 63d. The lifting plate 63a is, for example, a rectangular iron plate, and supports the underside of the sand mold portion SM formed inside the molding flask CF. The underside of the lifting plate 63a is supported by the support plate 63b.

[0063] The support plate 63b is made of, for example, iron and formed into a rectangular, thick plate. The support plate 63b prevents the removal plate 63a from being deformed by the force applied to it when the mold (sand mold portion SM) is shifted and removed from the molding flask CF, enabling smooth shifting and removal operations. A connecting portion 63c is provided at the center of the underside of the support plate 63b so as to protrude downward. The connecting portion 63c connects the upper end of the link member 5 to the support plate 63b of the lifting portion 63.

[0064] The connecting portion 63c is made of iron and is formed, for example, in a rectangular parallelepiped shape. A connecting hole 4e extending along the Y-axis direction is formed through the connecting portion 63c. The connecting hole 4e of the connecting portion 63c and the upper through-hole 5d of the link member 5 are connected by a shaft pin member SPM that communicates between the two holes. A ball bearing is provided in the connecting hole 4e.

[0065] The lifting plate 63a is provided with a cover member 63d. The cover member 63d is formed in a rectangular cylindrical shape, and is continuous at its upper end with the lower surface of the lifting plate 63a and is provided so as to surround the four side surfaces of the support plate 63b.

[0066] The cover member 63d extends at the bottom to near the lower end of the support leg 61, thereby covering the guide portion 62, link member 5 and support leg 61 and preventing spilled sand from entering the connection between the connection portion 63c of the lifting frame 6 and the link member 5 when the sand mold portion SM is removed.

[0067] A carry-in / carry-out conveyor LC is provided at the height of the lifting plate 63a of the lifting section 63 at the lower end (see Figure 1). The carry-in / carry-out conveyor LC includes a roller support member LCa extending in the Y-axis direction and a plurality of rollers LCb supported by the roller support member LCa. The poured mold PM (CF / SM) to be removed is transported by the carry-in / carry-out conveyor LC to a position where the sand mold portion SM is removed from the flask CF. The removed flask CF is transported to the next process for reuse. A lift-out control device 7 is provided above the carry-in / carry-out conveyor LC.

[0068] (Lift Restriction Device) The lift restriction device 7 holds down only the molding flask CF from above during mold removal, and is used when the sand mold portion SM is removed upward from the molding flask CF by the lift frame 6.

[0069] As shown in FIG. 1, the rise restricting device 7 includes a hydraulic cylinder device 71, a hydraulic switching valve, an oil tank, an air pressure switching valve, and an air pressure pump, all of which are not shown.

[0070] The hydraulic cylinder device 71 includes a cylinder portion 71a and a piston rod 71b.

[0071] 4 and 5, the lift-restricting devices 7 are fixed to the underside of the support frame HF so as to face the four corners of the flask CF being extracted and the centers of the two sides of the flask CF extending in the Y-axis direction. The support frame HF is part of the structure and is formed into a square frame shape with an open center and made of a member with a rectangular cross section.

[0072] The cylinder 71a has an opening that opens downward, through which a piston rod 71b advances and retreats. The piston rod 71b is made of, for example, iron and has a rod-like shape. The lower end of the piston rod 71b abuts against a corner of the upper end surface of the molding flask CF from which the sand mold section SM is extracted and against the centers of two sides of the molding flask CF extending in the Y-axis direction.

[0073] (Control Device) The control device controls the rotation of the electric motor 2 based on a signal of the rotation angle position of the arm member 4 detected by the rotation angle sensor. The control device switches the air pressure switching valve and the hydraulic switching valve to control the operation of the rise restriction device.

[0074] (Operation) Next, the operation of the poured mold removal device 1 configured as described above will be described below with reference to Figures 1 and 7 to 10. In the initial position, as shown in Figure 1, the rotating arm 30 is positioned so that the first connecting part FCP is directly below the drive rotation shaft RDS. The first link member 31 and the second link member 32 connected to the drive rotation shaft RDS hang down from the drive rotation shaft RDS. The arm member 4 is positioned at the clockwise rotation end, and the force point PF is at the lowest end. The application point PA of the arm member 4 and the lifting frame 6 are positioned at the lower end.

[0075] The poured mold PM (SM / CF) is carried by the carry-in / out conveyor LC to the position where the removal work will be performed. The removal plate 63a of the lifting frame 6 faces the underside of the sand mold portion SM with a gap therebetween.

[0076] Next, the control device rotates the rotating arm 30 counterclockwise as shown in Figure 7 (shifting process). A force moment based on the radius of rotation of the rotating arm 30 (the distance L1 between the drive rotation axis RDS and the center of the first connecting part FCP) acts on the force point PF of the arm member 4. Because the radius of rotation L1 is small, a large force acts on the force point PF despite the short movement distance. Furthermore, an even larger force acts on the action point PA due to the "leverage principle."

[0077] As described above, the poured mold removal apparatus 1 of the first embodiment is adapted to the situation where a large force is required for the lifting frame 6 to displace the sand mold section SM adhered to the flask CF upward from the flask CF in the early stage of removal. At this time, the lifting of the flask CF is restricted by the lift restricting device 7, causing a displacement between the flask CF and the sand mold section SM.

[0078] This force moment based on the radius of rotation (distance L1) acts until the rotating arm 30 rotates 180 degrees from the initial position, as shown in Figure 8. When the rotating arm 30 rotates 180 degrees from the initial position, the locking portion LP provided on the rotating arm 30 abuts against the locked portion LEP of the first link member 31 in the rotational direction. This causes the rotating arm 30 to take up the first link member 31.

[0079] Next, the control device further rotates the rotating arm 30 as shown in Figures 8 and 9. A moment of force based on the rotation radius L3 (the distance L1 minus the distance L2 from the center of the first connecting part FCP to the center of the second connecting part SCP) acts on the application point PA and the lifting frame 6. This moment of force acts when the rotating arm 30 rotates from 180 degrees to 360 degrees (the pulling-up process).

[0080] 9 shows the progress of the rotation arm 30 as it rotates through a rotation radius L3. When the rotation arm 30 reaches 270 degrees from the initial position, the arc-shaped portion ASP of the first link member 31 comes into contact with the regulating roller 205b, guiding the first link member 31 to rotate smoothly.

[0081] L3 is longer than L1, and the center of the second connecting part SCP moves with a larger radius of rotation. Therefore, the force applied to the force point PF is smaller, but the distance that the action point PA moves is longer and the movement speed is faster. In the latter half of the sand mold part SM removal operation, no large force is required, and moving the lifting frame 6 quickly is suitable for improving the takt time.

[0082] Next, as shown in Fig. 10, the control device rotates the rotary arm 30 from its initial position to 360 degrees. The lifting frame 6 then rises further, and the sand mold portion SM (including the casting) is removed from the flask CF. The removed sand mold portion SM (including the poured casting) is transported by a not-shown carrying-out device and further cooled.

[0083] The molding flask CF from which the sand mold portion SM has been removed is transported by the carry-in / carry-out conveyor LC to a process for reuse.

[0084] As is clear from the above description, the poured mold removal device 1 of the first embodiment comprises an electric motor 2, a lifting frame 6 that supports the underside of the sand mold portion SM that is inside the molding flask CF of the poured mold PM and allows it to be raised and lowered, and an arm member 4 that extends laterally and has a fulcrum F that serves as the center of rotation, a force point PF to which the driving force of the electric motor 2 is applied, and an action point PA that rotates based on the driving force applied to the force point PF.

[0085] The arm member 4 swings within an imaginary vertical plane, with its point of application PA located below the lifting frame 6 and at least its force point PF located away from the bottom of the lifting frame 6. The system also includes a drive force transmission mechanism 3 provided between the electric motor 2 and the force point PF of the arm member 4, a link member 5 extending vertically below the lifting frame 6 and connecting the point of application PA of the arm member 4 to the lifting frame 6, and a rise restriction device 7 that abuts against the outer periphery of the molding flask CF when the lifting frame 6 rises, restricting the rise of the flask CF.

[0086] This allows the point of application PA to be located below the lifting frame 6, and the mechanical parts (e.g., electric motors, gears requiring precise movement, complex link mechanisms incorporating ball bearings, etc.) including the force point PF to which the driving force is input can be located at a position away from below the lifting frame 6. This prevents the mechanical parts from being covered with casting sand that falls when the mold (sand mold portion SM) is removed, and solves maintenance problems such as wear and breakdown of the mechanical parts due to sand getting caught.

[0087] In addition, the hopper and conveyor that collect and transport the falling sand can be located away from the mechanism, eliminating the problem of limited installation space. Furthermore, because the arm member 4 is configured to operate on the principle of leverage, a small torque electric motor 2 can be used at the force point PF, making it possible to select an inexpensive electric motor 2 and reducing running costs during use.

[0088] In addition, in the poured mold removal device 1 of the first embodiment, the drive force transmission mechanism 3 includes a first mechanism (rotating arm 30) that generates the force required to shift the sand mold portion SM formed within the molding flask CF upward from the molding flask CF, and a second mechanism (first link member 31) that pulls the sand mold portion SM shifted by the rotating arm 30 further upward, and the force generated by the rotating arm 30 to shift the sand mold portion SM is greater than the force generated by the first link member 31 to pull it up, and the speed at which the sand mold portion SM is pulled up by the first link member 31 is greater than the speed at which it is shifted by the rotating arm 30.

[0089] According to this method, a rotating arm 30 is used to shift the sand mold section SM formed in the molding flask CF upward from the molding flask CF, which requires a large force to apply a load to the force point PF using the principle of leverage. The sand mold section SM shifted by the rotating arm 30 is then removed by the first link member 31, which has a high speed.

[0090] In this way, the electric motor 2, which is a single driving source, can efficiently operate the high load area where the load is raised at a slow speed and the low load area where the load is raised at a high speed according to the load required when removing the mold.

[0091] The first mechanism is a rotating arm 30 whose tip rotates at a predetermined radius when driven by the electric motor 2, and the second mechanism is a first link member 31 whose base end is connected to the tip of the rotating arm 30, is wound around the rotating arm 30, and whose tip rotates at a radius larger than the radius of rotation of the rotating arm 30.

[0092] According to this, the high load range where the lift is performed at a low speed is achieved by rotating the rotary arm 30 and winding up the first link member 31. Then, the low load range where the lift is performed at a high speed can be achieved by winding up the force point PF of the arm member 4 with the first link member 31, which is wound up on the rotary arm 30 and has a tip end with a larger radius of rotation than the rotary arm 30.

[0093] Furthermore, in the poured mold extractor 1, the rotating arm 30, arm member 4, and link member 5 move on the same plane (vertical plane), which allows the rotating arm 30, arm member 4, and link member 5 to be arranged compactly, thereby saving space.

[0094] Second Embodiment Next, a poured mold removal device according to a second embodiment will be described below with reference to Figures 11 to 19. As shown in Figure 11, a poured mold removal device 201 according to the second embodiment has an arm member 204 with two fulcrums F provided between a force point PF and a point of application PA.

[0095] Of the two supports F, the first support FF is used when shifting the sand mold portion SM (molten metal filled mold PM) formed in close contact within the flask CF upward from the flask CF, and the second support SF is used in place of the first support FF when the shifted sand mold portion SM is pulled further upward.

[0096] The electric motor 2 is provided at a position higher than the height of the base frame TBF. A rotating arm 2030 rotates by a drive rotation shaft RDS that is linked to the output shaft 21 of the electric motor 2, and the rotating arm 2030 and arm member 204 are connected by a single connecting link member 2031. The rotating arm 2030 and connecting link member 2031 form a driving force transmission mechanism 203. These points are different from the poured mold removal device of the first embodiment. The rest of the configuration is the same, so a description will be omitted. Below, the differences will be mainly explained.

[0097] (Base Frame) As shown in Figures 16 and 17, the base frame TBF is formed in a rectangular frame shape in a plan view. As shown in Figure 11, the base frame TBF has side portions SP that extend in the X-axis direction and have a shape with a downwardly bulging central lower portion when viewed from the Y-axis direction. Horizontal rail members TBF3 are provided at the bulging lower portions, supporting receiving portions RP that receive rollers RL (described later), and the horizontal rail members TBF3 connect opposing lower portions of the side portions SP (see Figure 13). The horizontal rail members TBF3 are arranged in pairs horizontally in the X-axis direction and extend along the Y-axis direction at positions below the receiving portions RP.

[0098] A pair of horizontal bars TBF4 is further provided at the center of each pair of horizontal bar members TBF3, extending perpendicularly between the horizontal bar members TBF3, as shown in Fig. 13. Each horizontal bar TBF4 is provided with a receiving portion RP for receiving a roller RL, which will be described later, as shown in Fig. 13.

[0099] 11, the receiving portion RP is formed of a pair of rectangular plates, each of which has a semicircular notch cut out at the top to form a half-moon-shaped recess RPa when the plates are upright. A roller RL (described later) is detachably supported in these half-moon-shaped recesses RPa. A roller guide RG (described later) is provided at a position corresponding to the first roller RL1.

[0100] The electric motor 2 is fixed via a pedestal to a mount TR, which is stacked and fixed on a base frame TBF. As shown in Figures 11 and 15, the mount TR includes a pedestal base PB, which is assembled to the base frame TBF in the shape of a rectangular parallelepiped with the same dimensions in the Y-axis direction, and a pedestal body PS, which protrudes beyond the base frame TBF in the Y-axis direction and has a flat frame shape. Diagonal support members TRa are provided between the lower ends of the pedestal body PS in the Y-axis direction and the outer side surfaces of the base frame TBF.

[0101] (Electric Motor) As shown in Figure 16, two electric motors 2 are fixed to the base frame TBF with their output shafts 21 facing each other. For example, a servo motor is used as the electric motor 2. When using two electric motors 2 to swing the arm member 204, it is desirable to drive one of the two electric motors 2 as a master and the other as a slave in order to synchronously control these electric motors 2. Note that, in some cases, inverter-controlled motors can also be used as these electric motors 2.

[0102] The output shafts 21 of the two electric motors 2 are connected to a single rotary drive shaft RDS via couplings. A rotary arm 2030 (described later) is attached to the rotary drive shaft RDS so as to be unable to rotate relative to the shaft.

[0103] The rotating arm 2030 in the second embodiment is made of, for example, iron and is formed of two long plate-like members whose width gradually narrows toward the tip. A connecting hole FCH that forms part of the first connecting part TFCP is formed at the tip, and the rotating arm 2030 is connected to the connecting link member 2031 at the first connecting part TFCP.

[0104] (Connecting Link Member) The connecting link member 2031 is formed from a single plate material in a boomerang shape with a bent middle portion. As shown in Fig. 15, an upper connecting hole UFCH is formed at the end of the connecting link member 2031 on the rotating arm side, and this hole is connected to the connecting hole FCH of the rotating arm 2030 by a pivot pin AP to form a first connecting portion TFCP. The middle portion of the connecting link member 2031 is bent so that the middle portion of the connecting link member 2031 does not come into contact with the drive rotation shaft RDS when the rotating arm 30 is positioned at the upper vertical position.

[0105] The rotating arm 2030 and the connecting link member 2031 are connected to each other so as to be rotatable within a virtual vertical plane in which the rotating arm 2030 rotates. A lower connecting hole DFCH is provided at the end of the connecting link member 2031 on the arm member 204 side, and constitutes a part of the second connecting part TSCP (see FIG. 15 ).

[0106] (Arm Member) In the second embodiment, the arm member 204 is made of, for example, iron, and the main body portion on the link member 5 side is formed from a single long plate. The end on the force point PF side is made of two short plates bonded together by, for example, welding so that the base end is sandwiched between the main body portion (overlapped portion 204a). A connecting hole FFCH is formed at the tip of the arm member 204 on the connecting link member 2031 side, and a pivot pin AP is inserted into the lower connecting hole DFCH of the connecting link member 2031, which is a single plate material, to connect the arm member 204. The lower connecting hole DFCH, the connecting hole FFCH, and the pivot pin AP form a second connecting portion TSCP (see FIG. 15 ). The arm member 204 is provided with a first roller RL1 (first fulcrum) located closer to the application point PA and a second roller RL2 (second fulcrum) located closer to the force point PF.

[0107] (Roller) As shown in Fig. 13, each roller RL is provided with a rotation support shaft (rotation shaft) RLd that is fixed so as to extend horizontally and penetrate the arm member 204 at a right angle. The rotation support shaft RLd is provided so as to be perpendicular to the vertical plane in which the arm member 204 swings. The roller RL includes a roller body RLa and a ball bearing RLb.

[0108] The pair of roller bodies RLa are formed, for example, in the shape of disks, and are arranged to sandwich the arm member 204 from both sides. A flange portion RLc is provided around the inside of the outer periphery of each disk (on the arm member 204 side). The flange portion RLc restricts lateral movement of the roller RL by the inside of the contact point of the receiving portion RP coming into contact with the flange portion RLc.

[0109] The roller body RLa has a through-hole at the center thereof, through which the rotation support shaft RLd passes, and the ball bearing RLb is fitted in the through-hole. The first roller RL1 is fitted into a roller guide RG provided on the side surface SP of the base frame TBF via a support plate HP.

[0110] (Roller Guide) As shown in Figures 13 and 14, the roller guide RG is formed of two rectangular plates, for example made of iron, and each plate has an opening OH through which the outer periphery of the first roller RL1 is inserted to move along an arc-shaped track. The roller guide RG supports the second roller RL2 on the receiving portion RP, and guides the first roller RL1 to move upward along the track when the effective fulcrum F switches from the first roller RL1 to the second roller RL2. Each roller guide RG is supported by two support plates HP that protrude inward from the side surface portion SP.

[0111] (Sand Cover) As shown in Fig. 12, the sand cover SC is formed in a gable roof shape from, for example, thin steel plates. The sand cover SC is disposed above the roller RL and the receiving portion RP to prevent the roller RL and the receiving portion RP from being covered with sand during mold removal. In relation to this, as shown in Fig. 12, the cover member 263d of the lifting frame 6 is formed with a triangular recessed avoidance portion AR to avoid contact with the roof-shaped tip of the sand cover SC.

[0112] The operation of the poured mold removing apparatus 1 of the second embodiment configured as above will be described below with reference to FIGS. 11, 18 and 19.

[0113] In its initial position, the rotating arm 2030 is positioned vertically upward, as shown in Figure 11. The connecting link member 2031 hangs down from the tip of the rotating arm 2030, raising the force point PF of the arm member 204. This position is the counterclockwise rotation end of the arm member 204. The first fulcrum FF of the arm member 204 is received by the receiving part RP, forming an effective fulcrum F. The point of application PA and the lifting frame 6 are at their lowest positions.

[0114] The poured mold PM (SM / CF) is carried by the carry-in / out conveyor LC to the position where the removal work will be performed. The removal plate 63a of the lifting frame 6 faces the underside of the sand mold portion SM with a gap therebetween.

[0115] Next, the control device rotates the rotating arm 2030 counterclockwise, moving the force point PF downward, as shown in Figures 11 and 18. As shown in Figure 11, the action point PA initially rotates with the first fulcrum FF (first roller RL1) as the effective fulcrum F, and although the radius of rotation is small, a large leverage force is exerted, causing the lifting frame 6 to rise. Then, as shown in Figure 18, the control device rotates the rotating arm 2030, bringing both the first fulcrum FF and the second fulcrum SF into a state where they are received by the receiving portion RP.

[0116] Next, the control device further rotates the rotating arm 30 and positions it vertically downward, as shown in Figure 19. The force point PF further descends, and the arm member 204 rotates the point of application PA with the effective fulcrum F as the second fulcrum SF. Because the radius of rotation is longer when the second fulcrum SF is used as the effective fulcrum than when the first fulcrum FF is used as the effective fulcrum, the point of application PA and the lifting frame 6 move by a larger distance and faster.

[0117] In this way, in the early stage of the extraction work, a strong force is exerted over a short distance, and in the later stage of the extraction work, a state in which the force is small but the movement distance is long and fast can be realized.

[0118] As is clear from the above description, in the device 1 for removing a poured mold in the second embodiment, the arm member 204 has a fulcrum F that is located between the force point PF and the action point PA, and the fulcrum F has two fulcrums: a first fulcrum FF and a second fulcrum SF that is located closer to the force point PF than the first fulcrum FF. The first fulcrum FF is used when the sand mold portion SM formed within the molding flask CF is shifted upward from the molding flask CF, and the second fulcrum SF is used in place of the first fulcrum FF when the shifted sand mold portion SM is pulled further upward.

[0119] According to this, when the same arm member 204 is used with the first fulcrum FF, the point of application PA is closer and the point of force PF is farther away than the second fulcrum SF, so that, according to the principle of leverage, a large force is likely to be generated at the point of application PA, even though the travel distance is short. When the second fulcrum SF is used, a large force is unlikely to be generated at the point of application PA, but a large travel distance can be ensured.

[0120] In addition, the first fulcrum FF and the second fulcrum SF are provided with a roller RL having a rotation support axis (rotation axis) RLd extending along a direction perpendicular to the vertical plane in which the arm member 204 swings, and a receiving portion RP having a crescent-shaped recess RPa corresponding to the outer peripheral shape of the roller RL, which removably supports the outer periphery of the roller RL in the vertical direction.

[0121] With this, the freely rotating roller RL and the receiving portion RP corresponding to the shape of the roller RL prevent the center of rotation of the arm member 204 from becoming misaligned even when the first fulcrum FF and the second fulcrum SF each become the fulcrum F. It is possible to easily and smoothly switch between the first fulcrum FF and the second fulcrum SF, which are in such a state where no misalignment occurs.

[0122] Further, a roller guide RG is provided at the first support point FF to guide the path of movement of the first roller RL1 that has come off the receiving portion RP.

[0123] According to this, when the effective fulcrum F switches to the second fulcrum SF, the first roller RL1, which was the first fulcrum FF, moves away from the receiving part RP, but the trajectory of movement is regulated by the roller guide RG, so that stable and safe movement can be achieved.

[0124] In the above embodiment, the rollers RL1 and RL2 are provided on the arm member 204 at the first fulcrum FF and the second fulcrum SF, and the receiving portions RP are fixed to the side surface portions SP of the base frame TBF, but this is not limiting. For example, the receiving portions may be provided on the arm member, and the rollers may be fixed to the side surface portions of the base frame.

[0125] Furthermore, regarding the electric motor, although one electric motor 2 is used as the drive source in the first embodiment, this is not limited thereto, and two electric motors may be used. Furthermore, although two electric motors 2 are used in the first embodiment, this is not limited thereto. For example, one electric motor may be used. Furthermore, although the receiving portion RP is a crescent-shaped recess RPa, this is not limited thereto. For example, both ends of the opening may be formed by vertical walls, and a pair of inclined walls may be provided that are continuous with the vertical walls and approach each other downward.

[0126] The present invention is not limited to the above-described embodiments shown in the drawings, but can be modified appropriately within the scope of the present invention.

[0127] 1: Poured mold removal device, 2: Electric motor, 3: Driving force transmission mechanism, 30: Rotating arm, 31: First link member, 4: Arm member, 5: Link member, 6: Lifting frame, 7: Lifting restriction device, 201: Poured mold removal device, 203: Driving force transmission mechanism, 2030: Rotating arm, 2031: Connecting link member, 204: Arm member, CF: Molding flask, PM: Poured mold, RG: Roller guide, RL: Roller, RLd: Rotating support shaft (rotating shaft), RP: Receiving part, SM: Sand mold part.

Claims

1. A poured mold removal device comprising: an electric motor; a lifting frame that supports the underside of the sand mold portion that is inside the flask of the poured mold, allowing it to be raised and lowered; an arm member that extends laterally and has a fulcrum that serves as the center of rotation, a force point to which the driving force of the electric motor is applied, and a point of action that rotates based on the driving force applied to the force point, the point of action being located below the lifting frame and at least the force point being located at a position outside the lower part of the lifting frame, allowing the arm member to swing within an imaginary vertical plane; a drive force transmission mechanism provided between the electric motor and the force point of the arm member; a link member that extends vertically below the lifting frame and connects the force point of the arm member to the lifting frame; and a rise restriction device that abuts against the outer periphery of the flask when the lifting frame is raised, restricting the rise of the flask.

2. The device according to claim 1, wherein the drive force transmission mechanism comprises a first mechanism that generates the force necessary to shift the sand mold portion formed within the molding flask upward from the molding flask, and a second mechanism that further pulls the sand mold portion shifted by the first mechanism upward, the force generated by the first mechanism for shifting the sand mold portion being greater than the force generated by the second mechanism for pulling the sand mold portion upward, and the speed at which the second mechanism pulls the sand mold portion out is faster than the speed at which the sand mold portion is shifted by the first mechanism.

3. The device described in claim 2, wherein the first mechanism comprises a rotating arm whose tip rotates at a predetermined radius when driven by the electric motor, and the second mechanism comprises a first link member whose base end is connected to the tip of the rotating arm and which is wound around the rotating arm so that its tip rotates at a radius larger than the radius of rotation of the rotating arm.

4. The device described in claim 1, wherein the arm member has a fulcrum provided between the force point and the point of action, the fulcrum comprising two fulcrums: a first fulcrum and a second fulcrum located closer to the force point than the first fulcrum, the first fulcrum being used when shifting the sand mold portion formed within the molding flask upward from the molding flask, and the second fulcrum being used in place of the first fulcrum when the shifted sand mold portion is pulled further upward.

5. The device according to claim 4, wherein the first and second fulcrums comprise: a roller having a rotation axis extending in a direction perpendicular to the vertical plane in which the arm member swings; and a receiving part having a crescent-shaped recess corresponding to the outer periphery of the roller, which removably supports the outer periphery of the roller in the vertical direction.

6. The device according to claim 5, wherein a roller guide is provided at the first fulcrum to guide the trajectory of the roller that has come off the receiving portion.

7. The device of claim 3, wherein said rotating arm, said arm member and said link member move in the same plane.

7. A method for removing a poured mold using the poured mold removal device of claim 1, comprising: a shifting step of relatively shifting the sand mold portion in the vertical direction to remove it from the molding flask; and a pull-out step of pulling out the sand mold portion shifted in the shifting step with a force smaller than that used in the shifting step and at a speed greater than that used in the shifting step.

Images