SU761123A1 - Apparatus for producing casting moulds - Google Patents

Description

The invention relates to foundry, in particular to devices for compacting molding molds by pressing.

Known pneumopress percussion, containing the base, mounted above it to the yoke, on which is mounted a piston drive with a press block; [1].

A disadvantage of the known construction is that the mixture is applied several blows to obtain technologically necessary density, which leads to a decrease in performance, as well as due to the low speed of the impactor of the necessary degree of compaction of the mold.

The purpose of the invention is to improve the performance and uniformity of the density distribution of the mixture at the height of the form.

This goal is achieved by the fact that the proposed device is equipped with a receiver placed on the traverse, inside of which the piston actuator is installed with a gap relative to its cover, the piston cavity of which is communicated with the cavity of the receiver.

FIG. 1 shows a device for the manufacture of molds; in fig. 2 -

pneumatic circuit device.

The device consists of a base 1, 2

movable upper traverse 2, rigidly interconnecting four columns 3. On the upper traverse 2 there is mounted an impactor, made in the form of two

5 interconnected and concentrically arranged cylinders, the outer 4 serves as a receiver, the working cylinder 5 in the upper part is open and freely communicates with the cylinder 4. Inside the cylinder 5 10 there is a piston 6 with a rod 7, and in the lower part a cylinder 5 has a cover with an opening 8 for air intake when lifting up the pressing block 9, the mass of which is 2-3 times the mass of the mixture. In order for the pressing block 9 not to rotate around a vertical axis, the device has guide rods 10. Two hooks 11 are used to hold the pressing block from spontaneous downward movement, at 20 which are pneumatic pushers 12.

When the mass of the pad is less than the specified limits, it is required to create very high speeds when moving downwards, which con25 is not structurally justified, and when the weight exceeds the specified limits

failure to seal the lower layers of the form.

There is a gap x between the upper end of the working cylinder 5 and the lid of the outer cylinder 4;

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the free flow of gas from the plane A of cylinder 4 to the above-piston cavity of the working cylinder 5.

In the static (non-working) position, the air pressure in the receiver and the working cylinder 5 is absent, the pressing block 9 is in the extreme upper position and held by the hooks 11. The distributors ΚΙ, K2, and short-circuit (Fig. 2) are in the "atmosphere" position.

The device works as follows.

Preparing to strike.

Distributor short circuit (Fig. 2) is translated to the "network" position. Compressed air from the line with a pressure of p = 5-6 kgf / cm ² enters through hole 13 into the cavity A of the receiver, where the air pressure also becomes p = 5-6 kgf / cm ² .

The distributor K1 connects the rod cavity of the working cylinder 5 with the atmosphere. On the base 1 of the device in a known manner, the model-mounting tool 14 is installed and the mixture 15 is filled up.

Impact pressing.

For the application of a single blow forging pads 9 on the free surface of the mixture. 15 is included distributor K2. Compressed air from the line through the distributor K2 enters the drive pneumatic actuators 12 and removes the hooks 11 from the press pad 9, the block 9 with the rod 7 and the piston 6 moves down.

Since the working pneumatic cylinder 5 ns has a top cover, the compressed air flows from the cavity of the outer cylinder 4 (receiver) with almost no loss to the working pneumatic cylinder 5, presses on the piston and creates a certain acceleration to the moving masses on the way of its movement.

At the end of the displacement path, the press block hits the free surface of the mixture 15 and compacts it in one blow.

The position of the "platoon" pressing block.

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The air from the receiver and the working cylinder after the impact is removed by connecting the receiver to the atmosphere. Then through the hole 8 in the bottom cover into the rod cavity of the working cylinder 5 is supplied compressed air, which lifts the moving parts of the impactor (piston 6. rod 7, press block 9) until it stops pads 9 into the bottom cover of the working cylinder 5. Then pneumatic pushers 12 transfer the hooks 11 under the pressing block 9 and the hooks 11 again hold the pressing block 9 in the upper position, Compressed air from the rod end of the working cylinder 5 through the hole 8 in the bottom cover and the distributor is released into the atmosphere.

The device is ready for the next cycle. Pulling the model and pushing the molded mold from the table of the machine provides high performance and quality of form compaction, however, it is silent in operation.

Claims (1)

Claim A device for making casting molds, comprising a base, a yoke fixed above it, on which a piston drive with a press block is installed, characterized in that, in order to increase the productivity and uniformity of the density distribution of the mixture over the height of the mold, it is provided with a receiver placed on the yoke inside which, with a gap relative to its cover, the above-mentioned piston actuator is installed, the piston cavity of which is in communication with the cavity of the receiver.