JP4421468B2 - Core removal device for cast iron pipe - Google Patents

Description

  The present invention relates to a method and an apparatus for removing a core for receiving a cast iron pipe immediately after casting.

  Today, cast iron pipes are less prone to defects such as blowholes and shrinkage cavities inside the casting, and the material is dense, making it possible to smoothly obtain good quality castings such as mechanical properties and productivity. From the point of being good, it is usually manufactured by a centrifugal casting method.

For example, as shown in FIG. 4, the cast iron pipe P is manufactured by rotating a cylindrical mold (mold) 11 with a roller 12 from a ladle 13 to a triangular ladle on the inner surface of the mold 11. The molten metal a is fed into the casting trough 15 through 14, and the molten metal a is cast into the mold 11 through the trough 15 (poured) to form a cylindrical molten metal layer (tubular body) b having a required thickness. Generally, it is performed by forming (see Patent Document 1).
JP 2004-58094 A

  In this centrifugal casting method, as shown in the figure, the core 17 for forming the receiving inner surface 1a is mounted in the receiving portion of the mold 11, and the space between the core 17 and the inner surface of the mold 11 (receiving) The molten metal a is fed into the mouth forming part) to cast the receiving port 1. In the figure, 2 is an insertion port for the cast iron pipe P.

The core 17 is usually formed by molding sand into a required shape with a resin binder or the like, and after the cast iron pipe P is extracted from the mold 11, if the binder burns out, it will naturally collapse and cast iron. It can be removed from the tube P receptacle.
However, normally, the core does not receive sufficient heat for the combustion of the binder, so it is not possible to expect its natural decay, and even if it spontaneously collapses, it takes a long time to collapse, so immediately after casting, The core 17 is positively removed.

  Conventionally, the core 17 is removed by hammering by an operator and hitting the outer surface of the receiving port 1 to give a shock to the core 17 to cause collapse. However, this operation is dangerous and severe because it deals with a heavy hammer near the cast iron pipe P where high temperature and high heat remain.

For this reason, a technique has been devised that automates hammering of the hammer and scrapes the collapsed core 17 with a scraping member (see Patent Document 2).
Further, by the axial claw blade of the core 17, a plurality of axial grooves are formed around the inner surface of the core 17 to divide the core 17, and the core 17 is collapsed by pulling out the claw blade or the like. A technique for removing them is also devised (see Patent Documents 3 and 4).
JP 2002-192329 A JP 2003-62649 A JP 2003-33855 A

  The removal of the core by the hammer damages the outer surface of the cast iron pipe P and lowers the commercial value. In the removal of the core by the nail blade, the core is divided by the groove in the axial direction, so that the core is difficult to be made small (fine) and the collapse thereof is difficult to be performed smoothly.

  An object of the present invention is to make it possible to smoothly remove the core.

In order to solve the above problems, the present invention brushes the inner surface of the core after cutting the inner peripheral surface of the core to a required depth.
If the inner peripheral surface of the core is cut (if scraped off), the thickness of the core is reduced, and the strength of the core is weakened due to vibration during the cutting, and the core becomes fragile.
If the thin and weak core is brushed, the core can be easily peeled off from the inner surface of the cast iron pipe, and the inner surface of the cast iron pipe receptacle can also be brushed to shorten work time such as shot blasting in the finishing process. Can do.
The cutting depth is appropriately set in consideration of the degree of removal of the core by brushing and the degree of not damaging the inner surface of the receiving port.

  In the present invention, as described above, after the inner peripheral surface of the core is cut to a required depth and then the inner surface of the core is brushed, the core can be removed smoothly and the finishing process can be performed. Improvements can also be made, improving productivity.

BEST MODE FOR CARRYING OUT THE INVENTION

As an embodiment of the method for removing the core for receiving the cast iron pipe according to the present invention, the inner peripheral surface of the core in the cast iron pipe receiving port immediately after casting is cut to a required depth, and then the inner surface of the core is brushed. Thus, a configuration for removing the core can be employed.
The above cutting includes the case where a circumferential groove is formed on the inner peripheral surface of the core. In this case, if the pitch in the axial direction is reduced, it can be of any length, Since the length of the core is extremely long compared to the groove in the axial direction, the core has a division ratio sufficient for its collapse, and the same effect as the removal of cutting can be obtained.
In brushing, if the brush forming the brush is pulled out from the inner side of the cast iron tube receptacle, the core debris removed by the brushing can be scraped out of the receptacle.

The inner peripheral surface of the core can be cut by various means. For example, the core inner peripheral surface is formed by a cutting tool that rotates relative to the cast iron pipe. At this time, the rotation center of the cutting tool is used as the axis of the cast iron pipe, and the rotation outer peripheral diameter is preferably set slightly smaller than the minimum diameter portion of the cast iron pipe receiving inner surface.
If the receiving end face of the cast iron pipe is also brushed, it is possible to improve the finish work time such as shot blasting of the end face.

  As an embodiment of the cast iron pipe receiving core removal device according to the present invention which constitutes the above-described core removal method for cast iron pipes, means for inserting / removing the cutting tool into / from the cast iron pipe, and the cutting tool and cast iron pipe It is possible to adopt a configuration comprising a means for relatively rotating around the axis of the cast iron pipe and a means for brushing the inner surface of the core by being inserted into and removed from the cast iron pipe.

More specifically, a moving body is provided on a base frame that is movable in a direction orthogonal to the axis of the cast iron pipe set at a predetermined position so as to be able to advance and retreat toward the cast iron pipe. The tool and the brush are rotatably provided by a motor, and the cutting tool or the brush is alternately placed in the cast iron pipe so that the tool can be inserted and removed by moving in the direction perpendicular to the axis of the cast iron pipe of the base frame. Thus, the cutting tool or brush is positioned in the cast iron pipe, the inner peripheral surface of the core is cut with the cutting tool, and the inner surface of the core is brushed with the brush to remove the core.

  At this time, it is a matter of course that a means for brushing the receiving end face of the cast iron pipe can be provided, and the brushing means may be constituted by a brush on the moving body, or other different from the brush. It can also be configured with a brush.

  1 to 3f, and as shown in FIGS. 1 and 2, this embodiment is a cutting device that cuts the inner surface of a molding core 17 in which sand is hardened to a required shape with a resin binder or the like. 30, a brushing device 40 that brushes the inner surface of the core 17, and a brushing device 50 that brushes the end surface of the core 17. The cutting device 30 and the brushing device 40 are provided on a base frame 22 that is movable on the rail 21 on the base 20. The base frame 22 can be moved to a required position in the front-rear direction (vertical direction in FIG. 1) by the rotation of the ball screw 23 by the motor M1.

  The cutting device 30 and the brushing device 40 are installed on a moving body 31 on the base frame 22, and the moving body 31 moves on the base frame 22 via the guide rod 33 by the rotation of the ball screw 32 by the motor M2. It is movable in the left-right direction (left-right direction in FIG. 1).

The cutting device 30 includes a left and right rotating shaft 35 rotatably supported on a moving body 31 via a bearing 34, and a replaceable cutting tool 36 provided at the tip of the rotating shaft 35. The cutting tool 36 has a required number of radial arms 36a extending from the center shaft portion (rotating shaft 35) at equal intervals around the center shaft portion (rotating shaft 35), and is provided at the tip of each arm 36a on a cutting tool 36b.
The attachment angle of the cutting tool 36b is appropriately set in consideration of the machinability and the like. The rotating shaft 35 is rotated by a motor M3 on the moving body 31 via a sprocket 37 and the like. The rotating outer diameter of the cutting tool 36 b is set slightly shorter than the minimum diameter portion of the inner surface of the receiving port 1.

  The brushing device 40 on the moving body 31 is movable to the moving body 31 in the front-rear direction (vertical direction in FIG. 1) via the guide rod 41, and is moved forward and backward by a certain length in the front-rear direction by the air cylinder 45. To do. In this embodiment, the inner diameter of the inner surface of the receiving port 1 of the cast iron pipe P is advanced and retracted. The brushing device 40 is configured by providing a replaceable brush 43 at the tip of a rotating shaft 42 that is rotated by a motor M4, and the brush 43 is rotated for brushing. As the brush 43, a well-known one that can smoothly peel off the core 17 such as a gold brush obtained by collecting steel wires in a radial manner is appropriately used.

  The brushing device 50 on the end face of the core 17 is provided on a ground having a height and a position where the movement of the base frame 22 is not hindered, and a moving body 53a (a base plate 53 described later) is placed on the frame 51 via a slide rod 52. 1 is located to be movable in one direction (left and right in the state of FIG. 1), and the movable body is moved by a motor and a ball screw mechanism or an air cylinder (not shown). The air cylinder and the like have the same configuration as the mechanism of the motor M3 and the ball screw 32 of the cutting device 30 and the air cylinder 45.

  A base plate 53 is provided on the upper surface of the movable body on the frame 51 so as to be rotatable at the center thereof. The base plate 53 is rotated 90 degrees by a rotary actuator (not shown). A rotation shaft 55 in the left-right direction in FIG. 1 supported rotatably on the base plate 53 via a bearing 54 is provided, and a replaceable brush 56 is provided at the tip of the rotation shaft 55. The rotating shaft 55 is rotated by the motor M5, and the brush 56 is rotated by the rotation to brush the object that contacts the rotating shaft 55. The brush 56 is made of the same material and structure as the brush 43.

  The core removing device of this embodiment has the above-described configuration. Next, its operation will be described. When the cast iron pipe P is cast by the centrifugal casting shown in FIG. As shown, the cast iron pipe P immediately after casting is conveyed and positioned at a predetermined position of the core removing device. At this position, the axis (rotation center) of the cutting tool 36 of the cutting device 30 and the axis c of the cast iron pipe P are the same.

  When the cast iron pipe P is positioned, as shown by the arrow in FIG. 3a, the cast iron pipe P is rotated, the cutting tool 36 is rotated, and the rotating cutting tool 36 is advanced through the movable body 31 to move the cast iron pipe. It is inserted into the inner surface of the P receptacle 1 (see FIG. 3b). As the cutting tool 36 is inserted into the receiving port 1, the inner peripheral surface of the core 17 is cut to a required depth (to the vicinity of the minimum diameter portion of the inner surface of the receiving port 1) by the cutting tool 36 (bite 36 b). The core 17 becomes thin and fragile.

On the other hand, as shown in FIG. 3 b, when the cutting tool 36 enters the cast iron pipe P, the brush 56 (rotating shaft 55) of the brushing device 50 is rotated 90 degrees as indicated by the arrow, and the brush 56 is moved to the receiving port 1. Opposite to the end face. Thereafter, in a state where the brush 56 is rotated, the moving body (base plate 53) is moved as shown by a chain line in the drawing, and the brush 56 is brought into contact with the end face of the receiving port 1 to brush the end face. By this brushing, as the cast iron pipe P rotates, the core sand 17 ′ attached to the entire circumference of the end face of the receiving port 1 is peeled off and falls into the bucket 60.
When the removal of the core sand 17 ′ at the end face of the receiving port 1 is completed, the brush 56 (rotary shaft 55) is rotated 90 degrees in the reverse direction before the cutting tool 36 is obstructed, and the standby position (chain line position). Return to.

When the cutting tool 36 reaches the tip of the core 17 (cuts to the tip of the core 17), the movable body 31 is moved backward. At this time, the rotation of the cutting tool 36 can be stopped.
If the movable body 31 moves backward and the cutting tool 36 moves away from the receiving port 1 (the same state as FIG. 3a), the base frame 22 is moved and the rotating shaft 42 of the brushing device 40 is moved as shown in FIG. 3c. It matches with the axis c of the cast iron pipe P. If they match, the moving body 31 is advanced and the brush 43 is inserted into the receptacle 1 as shown by the chain line in FIG.

  When the brush 43 reaches the innermost end of the core 17, as shown in FIG. 3d, the brushing device 40 is advanced by the air cylinder 45 while rotating the brush 43 to bring the brush 43 into contact with the core 17, and thereafter The moving body 31 is gradually retracted while the cast iron pipe P is rotated. By the rotation of the brush 43, the core 17 that is thin and is about to collapse is smoothly peeled off, and the scraped core pieces are scraped out of the receiving port 1 as the brush 43 retreats. The scraped core debris is dropped and stored in a bucket 60 installed below the receiving port 1. Instead of the bucket 60, a belt conveyor or the like can be employed.

  At this time, the degree of progress of the brushing device 40 (the degree of rod protrusion of the air cylinder 45) is appropriately set by experiment and actual operation so that the brush 43 smoothly removes the core 17 without damaging the inner surface of the receiving port 1. . Further, the retraction speed of the moving body 31 is also set appropriately in consideration of the degree of peeling of the core 17.

When the moving body 31 moves backward and the brush 43 moves away from the receiving port 1, the removal of the core 17 of the cast iron pipe P is completed, and the base frame 22 is moved to the initial state shown in FIGS. 1 and 3a. Return.
The cast iron pipe P from which the core 17 has been removed is moved to a required place, and a new cast iron pipe P with the core 17 is fed into the devices 30, 40, 50, and the cast iron pipe of the base frame 22 described above. The cutting tool 36 or the brush 43 is alternately placed in the cast iron pipe P so that the cutting tool 36 or the brush 43 can be inserted into and removed from the cast iron pipe P by the movement in the direction orthogonal to the axis of the P. Then, the inner peripheral surface of the core 17 is cut by the cutting tool 36 and the inner surface of the core is brushed by the brush 43 to remove the core . The above operation is repeated, and the cores 17 of the cast iron pipe P immediately after casting are sequentially removed.

In this embodiment, when removing the core sand 17 ′ of the end surface of the receiving port 1 by the brush 56, if there is a problem such as interference of the brush 56 with the movement of the cutting tool 36, the core on the inner surface of the receiving port 1 After the removal of 17, as shown in FIG. 3 f, the base frame 22 is moved and the brushing device 40 is pulled into the moving body 31, and the cutting device 30 and the brushing device 40 are moved away from the brushing device 50. .
Simultaneously with this action or after completion of the action, as shown in the figure, the brushing device 50 is rotated in the same manner as described above, and the end face of the receptacle 1 is brushed by the brush 56, and the receptacle 1 The core sand 17 ′ adhering to the end face can be peeled off.
Thus, when brushing the end face of the receiving port 1 after cutting, it is not necessary to rotate the cast iron pipe P during the cutting.

  In this embodiment, since the mold of the end face of the receiving port 1 is also carried by the core 17, the end face of the receiving end is brushed. However, when a sand mold is not used for the receiving end face forming portion of the mold, Since the core 17 remains, no brushing is required. In this case, a mold release material is applied to the mold so as not to be welded to the product.

Schematic plan view of one embodiment Outline front view of the same embodiment Operational diagram of this embodiment Operational diagram of this embodiment Operational diagram of this embodiment Operational diagram of this embodiment Operational diagram of this embodiment Operational diagram of this embodiment Schematic diagram of centrifugal casting method

Explanation of symbols

P Cast iron pipe a Molten metal 1 Cast iron pipe receiving port 17 Core 17 'Core sand 21 Rail 22 Base frame 30 Cutting device 31 Cutting device moving body 36 Cutting tool 36b Tool 40 Brushing device 43 Brush 50 Brushing device 56 Brush

Claims (2)

A cast iron pipe core removing device that removes the core (17) by brushing the inner surface of the core (17) after the inner peripheral surface of the cast iron pipe receiving core (17) immediately after casting is cut to a required depth. And means for inserting / removing a cutting tool (36) for cutting the inner peripheral surface of the core (17) to a required depth into the cast iron pipe (P), the cutting tool (36) and the cast iron pipe (P). And a means for relatively rotating the cast iron pipe (P) around the axis thereof and a means for brushing the inner surface of the core (17) by being inserted into and removed from the cast iron pipe (P).
A movable body (31) is provided on a base frame (22) movable in a direction orthogonal to the axis of the cast iron pipe (P) set at a predetermined position so as to be able to advance and retract toward the cast iron pipe (P). A means for inserting and removing is provided, and the moving body (31) is provided with the cutting tool (36) and the brush (43) serving as the means for brushing by means of motors (M3, M4), respectively, and rotating the means. The cutting tool (36) or the brush (43) can be inserted into and removed from the cast iron pipe (P) by moving the base frame (22) in a direction perpendicular to the axis of the cast iron pipe (P). in conjunction to position the cutting tool with the progress of the moving body (31) to (36) or brush (43) by positioning the cast iron pipe (P), the core (1 by its cutting tool (36) After cutting) inner peripheral surface, said brush (43) cut by the core (17) by brushing an inner core (17) cast iron pipe core for removing apparatus characterized by removing the.   The core removing device for cast iron pipe according to claim 1, further comprising means for brushing the end face of the receiving port (1) of the cast iron pipe (P).

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