JPS6243778B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an apparatus for manufacturing castings, particularly foundry cores, using heated tools.

The invention can be used in production plants in automobiles, sanitary engineering, electrical engineering, machine construction and other industries where large batches or mass production are involved.

In recent years, methods for producing foundry cores directly using core molds have been widely applied around the world, but these methods have been divided into so-called "heat-box" and "cold-box" methods. This is the ``cool-box'' method.

To manufacture cores using the “thermal mold” method, sand,
Core sand composed of a binder and a catalyst can be blown into a heated core mold. Under the action of heat and catalysts, the core sand hardens by rapid polymerization of the binder.
The Foundry Machine Building Shop produces a series of multi-station devices that operate on the principle of "thermo-mold". This equipment includes a core blowing machine, a device for disassembling core molds and delivering the completed cores, a device for heating the core molds, and a device for disassembling the core molds from one station to another. The facility is equipped with a means of transport to transport the station to the station.

This device operates as follows.

At the first station, the hot mold is pressed against the sand blowing plate and the hot mold is filled with sand. A second station is designed to inspect and modify the core mold.
The sand then hardens at several stations as the core molds are heated, either by passing them through a heating chamber or by energizing heaters built into them. At the final station, the core mold is opened, the completed core is removed, and then compressed air is blown into the core mold.

To produce cores using the “cold mold” method, sand can be blown into a cold mold followed by blowing with a gaseous catalyst (Ashland cold mold method).
Alternatively, the sand may be hardened by using a highly reactive binder with a large amount of catalyst (Fascold or Gisag cold-type process).

Equipment for producing foundry cores based on the "cold mold" principle is widely known.

Overall, devices that work on the "hot-type" or "cold-type" principle, increasing efficiency, increasing the strength of the sand and improving the working conditions, are especially useful for all Cores such as cores for heating boilers and radiators whose sides are cast with metal and do not come into contact with the mold except for two small core receivers cannot be vented effectively. Since the sand hardens uniformly over its cross-section, creating a core of two halves glued together provides venting of the core and communication with the atmosphere. These additional process operations complicate core manufacturing, increase labor requirements, impair the geometric and dimensional accuracy of the core, and impede the intricate automation of core manufacturing. It will be done.

A method and a device for implementing the method are known (FRG patent no. 2239057
No., CI, B22C9/10).

This method involves forcing the fluidized sand into a heated core mold, sealing the core mold tightly, and then holding it for the specified time necessary to harden the sand before forming the finished core. The purpose is to extract the

According to this method, any core can be made in a single piece, since a natural conduit or hole is formed in the center of the core during curing, through which gas can effectively escape. The device comprises a starting sand component equipment and batcher, a mixer with a gate cutting off the discharge port, a pressurized cylinder with a ram, a batch chamber, a sliding damper with an extendable nozzle, an elevating and lowering. It consists of a table and operates as follows.

The starting components of the sand are fed into the mixer, where they are agitated and during the process are moved to the discharge port to form the finished fluidized sand and transferred to a batch chamber with a damper at the bottom. As soon as the batch chamber is filled with sand, a gate closes the mixer discharge port, a damper slides to align the nozzle with the batch chamber, and a table rises to move the heated core molds into the nozzle. Press. A pressurized cylinder acts on a ram to pack the sand into the core mold.
As soon as this is completed, the core mold is sealed to prevent sand from being released through the inlet opening. After a certain period of time necessary for the air bubbles to reduce and for the sand to lose its mobility, the core mold can be transferred to the next station. The damper closes the bottom of the batch chamber again, the ram returns to its initial position, and the gate opens the mixer discharge port. Then the cycle repeats.

The pressure within the core mold increases under a set of conditions and reaches a value sufficient to overcome the weight of the upper half of the core mold. Therefore, if the core mold, after being packed and sealed with sand, is held in a pressurized position for a certain period of time, its upper half will be pushed up and some flow will flow along its separation plane, which will inevitably lead to defects. I become a certain middle child.

Hardening of sand requires much more time than "hot" or "cold" methods. This is because hardening in this case occurs primarily through evaporation of moisture from the fluidized sand.

If the core is held too long after the sand is pressurized or if the sand hardens too long, the core manufacturing time will be substantially longer, and this will result in a "hot mold" or a "cold mold". The efficiency of the machine is somewhat reduced compared to equipment operating on the principle of ``, and therefore the advantages that the machine offers in large batch production and mass production operations are also somewhat reduced.

A particular drawback of this known machine is that it is ingenious in permanently clamping the two halves of the core mold together from the moment the core mold is filled with sand until the moment it is opened. be. Fill the core with as much sand as necessary to sufficiently reduce the sand pressure within the core mold and prevent the top of the core mold from lifting once the core mold is released. The compressed core mold is held between the table and the pressure mechanism for a considerable length of time, which reduces the efficiency of multi-station machines and where the upper half of the core mold becomes vertical due to residual pressure. There is also no absolute guarantee that the device will not move from its fixed position. As a result of such movement, distortions occur in the geometrical dimensions of the core and its quality deteriorates over time.

The aim of the invention is therefore to obviate the above-mentioned drawbacks.

The invention ensures a reliable clamping of both halves of the core mold from the moment prior to filling with sand until the moment of disassembly, prevents the upper half of the core mold from moving in the vertical plane, and ensures maximum The object is to provide an apparatus for producing foundry cores by forcing fluidized sand into a heated core mold, designed to achieve efficiency.

This purpose consists of a supporting frame formed with two floors: a lower floor carrying the transport means and transfer table and an upper floor carrying the sand preparation and pressing mechanism, a pushing member with cross members and a heating In an apparatus for producing foundry cores, which includes a chamber and a mechanism for disassembling a core mold and delivering the completed core,
This is achieved according to the present invention as follows. namely, a device placed before the heating chamber for tightening the two halves of the core mold together, and a device placed after the heating chamber and intended for loosening the two halves of the core mold. A device is provided, and each core mold is equipped with a
providing two horizontal bars with conical elements arranged in the lower half of the core mold and cooperating with the above-mentioned device for tightening and loosening the core mold;
Also provided are two vertical bars fixed to the upper half of the core mold, and the lower ends of these bars are provided with conical holes and slots intended to cooperate with the conical elements of the horizontal bars. be.

The device for tightening the two halves of the core mold is constructed as a horizontal piston actuator pivotally mounted on the cross member of the pushing member, and the device for loosening the two halves of the core mold is constructed as a horizontal piston actuator pivoted on the cross member of the pushing member. It is expedient to construct it as a bracket with adjustable stops attached to the mechanism for disassembling the mold.

According to the invention, a transfer table lifts the core mold from the transport means and delivers it to the pressing mechanism.
The device for tightening the two halves of the core mold acts on the horizontal rod of the core mold in such a way that the conical element of the horizontal rod enters the conical hole of the vertical rod. This creates a wedge effect to ensure that both halves of the core mold are tightly tightened. This action eliminates the need to hold the two halves of the core mold together after pressurization and substantially reduces the operating cycle of the device. A device for tightening the two halves of the core mold is pivotally mounted on the crosspiece of the push member, thereby preventing an accident in which the movable element cannot be returned to its initial position. A pressing mechanism packs the sand prepared by the sand preparation mechanism into the core mold, seals the core mold, and transfers it directly by means of a pusher to a heating chamber containing several other core molds. As soon as the first core mold is pushed into the heating chamber, the last core mold is ejected into the action area of a mechanism for delivering the finished core, which transfers the core mold to the transfer table. Pull. At the end of the stroke, the horizontal bar of the core mold contacts an adjustable stop on a bracket attached to a mechanism for disassembling the core mold, and the core mold is returned to its initial position. This provides a wedging action that loosens the core mold halves. The conical element of the horizontal rod is moved out of the conical hole of the vertical rod, and at the same time the core mold is unsealed. In this way, good advantages are obtained by transferring the core mold to the transfer table, and an adjustable stop provided on the mechanism for opening the core mold and disassembling the core mold makes it necessary This provides two additional functions: the length of travel is determined, and the slot allows the vertical rod to be disengaged from the horizontal rod.

As soon as the core has been removed, the core is reassembled by means of a mechanism for disassembling the core mold and lowered by means of a transfer table onto the transport means, which returns the core mold to the pressing mechanism station.

The multi-station device is built on two levels to keep its width as small as possible and to easily seat in existing floor space. This equipment nearly doubles production capacity and stabilizes core quality.
It must be emphasized that by firmly tightening both halves of the core mold from the moment of filling the core mold with fluidized sand until the moment of disassembling the core mold, contamination of the mechanism is substantially reduced and The core manufacturing process has never been so clean.

Hereinafter, the present invention will be explained with reference to specific embodiments thereof, with reference to the accompanying drawings.

Equipment for producing foundry cores (Figs. 1 to 6)
Figure) comprises a support frame 1 formed with two levels, the lower level carrying the transport means 2 and the transfer tables 3 and 4, and the upper level carrying the sand preparation mechanism 5.
and a pusher member 7 carrying a pressure mechanism 6 and having a crosspiece 8 on which a piston actuator 9 is pivotally mounted.
a heating chamber 10, a mechanism 11 for disassembling the core mold together with a bracket 12 and an adjustable stop 13, and a mechanism 1 for delivering the finished core.
4.

The core mold 15 has an upper half 16 and a lower half 17, and these halves are locked together by pins 18 and bushes 19. The upper half 16 carries, on diagonally opposite sides, a vertical bar 20 with a conical hole 21 and a slot 22, and a built-in gate 23 which serves to seal the core mold 15. The lower half 17 incorporates an ejector 24 and a bush 25 designed as a guide for a horizontal bar 26 with a conical element 27 . Sand is charged into the core mold through the entrance hole 28. This device operates as follows.

A transfer table 4 lifts the core mold from the transport means 2 and delivers it to the pressurizing mechanism 6. The piston actuator 9 moves the horizontal bar 26 of the core mold 15 inside the bush 25, so that the horizontal bar 2
The conical element 27 of 6 is connected to the conical hole 21 of the vertical rod 20.
to engage. This creates a wedge effect that locks the two halves of the core mold 15 together. The pressure mechanism 6 packs the sand supplied by the sand preparation mechanism 5 through the inlet hole 28. The gate 23 is moved to close the hole 28, the core mold is hermetically sealed, and it is directed into the heating chamber 10 by the pushing member 7.
The heating chamber 10 accommodates several other core boxes. When a new core box is loaded into the heating chamber, the last core mold is discharged from there into the active area of the mechanism 14 for delivering the finished cores.
The mechanism 14 pulls the core mold out of the heating chamber 10 onto the transfer table 3, which is then in the top position. At the end of the stroke, the horizontal bar 26 comes into contact with the adjustable stop 13 of the mechanism 11 for disassembling the core mold and is guided into the initial position by the bush 25. This creates a wedge effect that opens the two halves of the core mold. The conical element 27 of the horizontal bar 26 moves out of the conical hole 21 of the vertical bar 20. At the same time, the core mold is unsealed and its gate 23 returns to its initial position.

A mechanism 11 for disassembling the core mold opens the core mold, and the vertical rod 20 can be disengaged from the horizontal rod 26 by virtue of the slot 22. Ejector 2
As soon as the core mold is extruded by 4 and removed from the core mold, the core mold is reassembled and lowered onto the transport means 2 by the transfer table 3, which moves the core mold toward the transport table 4. let Another operating cycle of the device is started when the transfer table 4 is moved upwards together with the core mold.

The apparatus of the present invention maintains cores with high precision both dimensionally and geometrically and is approximately twice as efficient as existing core making machines.

[Brief explanation of the drawing]

Figure 1 is a schematic diagram of an apparatus for producing foundry cores;
Figure 2 is a view taken along the arrow "A" in Figure 1, Figure 3 is a sectional view taken along the line - in Figure 2, and Figure 4 is a cross-sectional view taken along the line - in Figure 3. 5 is a cross-sectional view taken along line - in FIG. 3, and FIG. 6 is a view taken along arrow "B" in FIG. 7... Pushing member, 8... Cross member, 9... Piston actuator, 10... Heating chamber, 11... Mechanism for disassembling the core mold, 12... Bracket, 13... Adjustable stop, 15... Core mold, 16 ...The upper half of the core mold,
17...lower half of core mold, 20...vertical rod, 21...
Conical hole, 22...slot, 26...horizontal bar,
27...Conical element.

Claims (1)

[Scope of Claims] 1. A support frame formed with two floors: a lower floor carrying a transport device and a transfer table, and an upper floor carrying a mechanism for preparing and pressurizing the sand, and a cross member. A foundry core is produced by press-fitting fluidized sand into a heated core mold, comprising a pushing member having a structure, a heating chamber, and a mechanism for disassembling the core mold and delivering the completed core. In an apparatus for manufacturing core molds 15, there is a device arranged before the heating chamber 10 for tightening the core molds 15 together, and a device arranged after the heating chamber 10 and intended for loosening the core molds 15. and in the lower half 17 of each core mold 15 there is a conical element 27 cooperating with said device for tightening and loosening the core mold 15.
There are two horizontal bars 26 with
a conical hole 21 for cooperating with a conical element 27 of
1. A casting core manufacturing device characterized by having a slot and a slot. 2. The device for tightening the core mold 15 is formed with two horizontal piston-type actuators 9 pivoted to the cross member 8 of the pushing member 7, whereas the device for loosening the core mold 15 is The device includes a bracket 12 with an adjustable stop 13 attached to the mechanism 11 for disassembling the core mold 15.
2. The device according to claim 1, wherein: