JPS6243776B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a molding device for a centrifugal casting core.

When performing centrifugal casting of tubes, an annular core is placed at the end of the mold to form the tube socket. Traditionally, core molding methods include placing sand with a thermosetting resin as a binder in the core mold and accelerating hardening with a burner or hot air, or sealing the core mold and using CO2 after adding self-hardening sand. Methods of curing by filling with a reactive gas such as ₂ gas or triethylamine gas and causing a passage reaction have been used. However, with such conventional products, in order to mold cores for tubes with different diameters, core molds corresponding to the types are required. In addition, uneven thickness tends to occur when molding the core, which causes wobbling in the mold during centrifugal casting due to rotation of the mold.
will not be obtained.

An object of the present invention is to provide a centrifugal casting core manufacturing apparatus that can be used for most of the molding of multiple types of cores, and that can also provide a molded core with a uniform wall thickness in the circumferential direction. The point is to provide the following.

In order to achieve the above object, the centrifugal casting core molding device of the present invention is provided with a table rotatable around the vertical axis, and a rotary drive device interlocked with this table. One of the plurality of types of molds forming the core molding surface is configured to be able to be placed on the table, and a centering device is provided for aligning the mold with respect to the vertical axis. A locking device is provided to fix the formed mold on the table side, and a sand projecting nozzle and a sand scraping plate are provided opposite to the core forming surface.

According to this configuration, a mold corresponding to the diameter of the core to be molded is taken out and placed on the table, and after this mold is aligned with the centering device, it is fixed on the table side with the locking device. A core of the desired diameter can be molded. Therefore, by simply preparing molds of various diameters, most of the equipment can be used in common, and equipment costs can be reduced. Furthermore, when molding a core by supplying sand toward the core molding surface, the inner surface of the core can be shaped with a sand scraping plate, so uneven thickness does not occur, that is, the circumference A core with uniform wall thickness can always be obtained in all directions. This can prevent rattling from occurring during centrifugal molding, and it is possible to always obtain good quality cast products (tubes).

An embodiment of the present invention will be described below based on the drawings. Reference numeral 1 denotes a base plate disposed on a machine frame 2, which rotatably supports an outer cylinder shaft 4 in the vertical direction via a bearing device 3. A table 5 is fixed to the upper end of the outer cylinder shaft 4, and the table 5 is rotatable around a vertical axis 6. Reference numeral 7 denotes a rotary drive device linked to the table 5, which includes a lower cylinder shaft 8 integrated with the lower end of the outer cylinder shaft 4, a passive wheel body 9 attached to the lower end of the lower cylinder shaft 8, and the base plate 1. Motor 1 installed in
0, a driving wheel body 12 attached to the output shaft 11 of this motor 10, and an endless body 13 wound between the two wheel bodies 9 and 12. Reference numeral 14 denotes a mold that can be placed on the table 5, and is composed of a ring 15 and a mold 16 disposed above the ring 15. This formwork 16 is divided into three parts (multiple divisions) in the circumferential direction, and the outer peripheral surface thereof is formed into a tapered surface 17 whose diameter becomes larger toward the lower part. Also, a mold 14 composed of a ring 15 and a mold 16
The inner circumferential surface of is formed as a core molding surface 18. A plurality of types of molds 14 are prepared, one of which is for the purpose.
is placed on the table 5. 19 is a centering device for aligning the mold 14 with respect to the vertical axis 6;
and an intermediate transmission bevel gear 21 attached to the upper end of this vertical shaft 20 and a passive bevel gear 22 attached to the lower end.
a horizontal shaft 24 rotatably disposed on the lower surface side of the table 5 via a bearing 23; and an intermediate passive bevel gear attached to the inner end of the horizontal shaft 24 and constantly meshing with the intermediate transmission bevel gear 22. 25 and the horizontal axis 2
Nut body 2 screwed into threaded portion 26 formed in 4
7, which is erected from this nut body 27 and forms part of the formwork 1.
A protrusion 29 that fits into a recess 28 formed on the bottom surface of 6
, a drive bevel gear 30 that can engage and disengage from the passive bevel gear 22, and an operation rotating shaft 31 that can be pushed and pulled to which the drive bevel gear 30 is attached. Formwork 16
Three sets are provided so as to correspond to each other, and a handle is provided at the end of the operating rotation shaft 31. 32
is a locking device that fixes the centered mold 14 on the table 5 side, and includes an inner cylinder shaft 33 that is arranged to be relatively rotatable between the outer cylinder shaft 4 and the vertical shaft 20, and a locking device that fixes the centered mold 14 on the table 5 side. An elevating cylinder body 35 is externally fitted via a threaded portion 34 and guided to the inner surface of the outer cylinder shaft 4 so that it can only be raised and lowered via a spline or a key, and a connecting tool 36 is connected to the elevating cylinder body 35 at a free end. a vertically swingable lever 38 whose base end is connected to the table 5 side via a horizontal pin 37, and a lifting rod 39 connected to the middle of this lever 38 so as to be relatively swingable; A ring-shaped lifting frame 40 connected to this lifting rod 39 and arranged on the table 5
A taper ring 43 is replaceably attached to the inside of the lifting frame 40 via a lock ring 41 and has an inner surface formed into a tapered surface 42 that can match the tapered surface 17, and the inner cylinder shaft 33. A passive bevel gear 44 attached to the lower end, a driving bevel gear 45 that can engage and disengage from the passive bevel gear 44, an operating rotating shaft 46 that can be pushed and pulled to which the driving bevel gear 45 is attached, and this operating rotating shaft 46. It consists of a handle 47 attached to the end of the drive bevel gear 45, and a spring 48 that urges the drive bevel gear 45 to move in the disengagement direction. A bearing device 3 to a table 5 are mounted on the base plate 1.
A safety cover 49 is provided that surrounds the outside. Reference numeral 50 denotes a sand scraping plate that can face the core molding surface 18, and is provided with a sand projection nozzle 51 that can similarly face the core molding surface 18. This sand projection nozzle 51 is connected to a sand supply device (not shown) via a hose 52. The sand scraping plate 50 is movable between a position facing the core molding surface 18 and a position away from the core molding surface 18, and is configured to be able to approach and move away from the core molding surface 18 while facing the core molding surface 18. That is, a horizontal plate 53 is attached to the upper end of the safety cover 49, and a horizontal screw shaft 55 is rotatably provided on the horizontal plate 53 via a bearing 54. A drive gear 57 that meshes with a passive gear 56 attached to a screw shaft 55 is supported on the horizontal plate 53 side, and a handle 58 that interlocks with the drive gear 57 is provided.
Furthermore, a nut body 5 is externally fitted onto the screw shaft 55.
9 is provided, and the sand scraping plate 50 is attached to the tip of a lever 61 which is attached to the nut body 59 via a horizontal shaft 60 so as to be able to swing up and down. A slide plate 62 integrated with the nut body 59 and the lever 6
1, a cylinder device 63 for swinging this lever 61 is provided. Reference numeral 64 indicates the core, and 64a indicates the inner surface of the core.

The action will be explained below. First, the installation work of the mold 14 will be explained. Before the installation work is carried out, the sand scraping plate 50 is in the retracted position, and the tapered ring 43 has been removed together with the mold 14. Further, the lifting frame 40 is at the upper limit position, and the protrusion 29
is located on the outside. The drive bevel gear 45 is separated by the force of the spring 48, and the drive bevel gear 30 is also separated in the same way. In this state, the ring 15 corresponding to the core to be molded next is placed on the table 5, and the formwork 16 divided into three parts is placed on the outside of the ring 15, and the recess 28 is It is fitted into the protrusion 29. Next, push the operating rotation shaft 31 to move the driving bevel gear 30 to the passive bevel gear 2.
The operation rotation shaft 31 is rotated in a state in which the operation rotation shaft 31 is engaged with 2. This rotational force is transmitted to the vertical shaft 20 and further rotates the horizontal shaft 24 via the bevel gears 21 and 25.
As a result, the nut body 2 screwed into the threaded portion 26
7 advances, each formwork 16 is advanced through the protrusion 29, and the ring 15 is aligned with the vertical axis 6.
At the same time, each formwork 16 is integrated with the ring 15 in a self-aligned state. Next, a desired taper ring 43 is arranged on the inner surface of the elevator frame 40 in the raised position and is integrated with the lock ring 41. In this state, the operation rotation shaft 46 is pushed to cause the driving bevel gear 45 to engage with the passive bevel gear 44, and then the operation rotation shaft 46 is rotated. This rotational force is transmitted to the inner cylinder shaft 33 and lowers the elevating cylinder body 35 via the threaded portion 34. This allows the horizontal pin 37
The lever 38 moves downward around the lever 38, lowering the lifting rod 39 and lowering the tapered ring 43 together with the lifting frame 40. Therefore, the tapered surfaces 17 and 42 are pressed together, and the mold 14, which has been aligned, can be locked. The mold 14 is installed in this manner, and can be removed by performing the reverse operation. Next, the molding work will be explained. First, handle 58
is operated to advance the nut body 59, extend the cylinder device 63, and move the lever 61 downward.
A sand scraping plate 50 is placed opposite to the core molding surface 18. Next, the nut body 59 is moved back to bring the sand scraping plate 50 closer to the core molding surface 18, and the sand scraping plate 50 is positioned. In this state, the rotary drive device 7 is operated, and while the mold 14 and the table 5 are rotated around the vertical axis 6, sand is projected from the sand projection nozzle 51 onto the core molding surface 18. As a result, the core 64 is gradually centrifugally molded on the core molding surface 18. The inner circumferential surface of the molded core 64 is shaped by the sand scraping plate 50, thereby making it possible to mold the core 64 with a uniform thickness in the circumferential direction.

[Brief explanation of the drawing]

The drawing is a longitudinal sectional view showing an embodiment of the present invention. 1...Base plate, 3...Bearing device, 4...Outer cylinder shaft, 5
...Table, 6...Vertical axis, 7...Rotation drive device, 1
4... Mold, 15... Ring, 16... Formwork, 17... Tapered surface, 18... Core molding surface, 19... Centering device, 2
0...Vertical axis, 28...Recess, 29...Protrusion, 32...Lock device, 33...Inner cylinder shaft, 34...Threaded part, 35...Elevating cylinder body, 38...Lever, 39...Elevating rod, 40
... Lifting frame, 41... Lock ring, 42... Tapered surface, 43... Taper ring, 50... Sand scraping board, 51
...Sand projection nozzle, 64...core, 64a...core inner surface.

Claims (1)

[Claims] 1. A table rotatable around the vertical axis is provided, and a rotary drive device is provided that is linked to this table, and one of the plurality of types of molds whose inner circumferential surface forms a core molding surface is placed on the table. A centering device is provided for aligning the mold with respect to the vertical axis, and a lock device is provided for fixing the centered mold to the table side, and a locking device is provided for fixing the centered mold to the table side. A molding device for a core for centrifugal casting, characterized in that it is provided with opposing sand projecting nozzles and a sand scraping plate.