SU501830A1 - Press form - Google Patents

Description

The invention relates to foundry and can be used in the manufacture of low-melting models with spherical interior lines, for example, with undercuts, in the production of precision casting.

According to the main author. St. No. 442008 is a well-known mold for making models, comprising a movable zero shape with two-stage rods with elastic cores and tips fixed on it, and a fixed half-form provided with an intermediate plate on which the stop bushings interacting with the cores are fixed. The cores have the shape of an ellipse truncated on both sides.

Before pressing the model mass into the mold cavity, elastic cores are compressed, which take the form of internal cavities of the models. When the shape is opened, the load from the cores is removed and they, straightened, acquire the initial form and are removed from the models.

The disadvantage of such a mold is a decrease in the stability of the cores as a result of the notary of their elastic properties under the repeated action of the load, which leads to the rejection of models.

In order to eliminate this drawback in the proposed mold, the movable half-form is provided with sleeves rigidly attached to it, covering two-stage rods and having limiting shoulders connected to the cores,

the rods are made spring-loaded with the possibility of longitudinal movement, and the tips of the rods are equipped with flanges with restrictive shoulders connected to the cores from the fixed half-form. In addition, the ends of elastic cores are made in the form of cylindrical bridges with annular grooves of a rectangular shape, and the restrictive shoulders of the sleeves and flanges of the tips of the rods are provided

L-shaped protrusions.

FIG. 1 shows the described mold at the time of pressing; in fig. 2 - the same at the time of disclosure; in fig. 3-node I in FIG. 1 (attachment point for flanges of lugs with elastic cores, the mold is closed).

The mold includes two half-molds: movable 1 and fixed 2. There are threaded bolts 3 on the movable semi-mold,

on which are screwed hollow sleeves 4, equipped with restrictive shoulders 5 with Mr. on different projections.

The sleeves 4 are placed with the possibility of relative movement under the action of

the springs 6 are two-stage rods 7 with protruding tips 8, on which elastic cores 9 are located, as well as flanges 10 with protrusions similar to the protrusions of the bounds of the burt.

The cores are made of elastic material (preferably silicone rubber) and in the normal state in the longitudinal section they have the form of an ellipse with cylindrical sections 11 that are attached to it from two sides, on which circular grooves 12 are pipYiMogylnogo shape (fig. 3).

In working condition, the cores are fastened, on the one hand, with sleeves 4 orts of L-shaped protrusions entering grooves 12, and on the other hand, similarly with flanges 10. Such a lock connection of the cores provides ease of installation and reliability in operation.

A pneumatic cylinder 13 is mounted on a baseless half-form, the stem of which carries an intermediate plate 14. On this plate, according to the number of models, are thrust bushings 15, the inner diameter of which is sleeved with a diameter of a smaller step of rods. For the proposed construction, the sleeves 4 and the flanges 10 serve simultaneously as rods for producing holes in the models.

The mold works as follows.

With the flow of air into the cylinder 13, the plate 14 with bushings 15 moves to the left. The sleeves 15, interacting through the flanges 10 with elastic cores, compress them with a force sufficient to give them a given configuration. Under the action of this force, the rods with tips also move to the left and compress the springs 6 in this case. The final amount of movement of the cylinder rod is adjusted by the screw 16.

After the model mass is pressed in and cured, the cylinder rod retracts to the right. In this case, the load from the cores is removed and the latter, under the combined action of the elastic forces of the material and the springs 6, are straightened, take the initial configuration before compression, and partially leave the cavity of the models.

The stiffness of the springs is chosen to be approximately equal to the elasticity of the newly manufactured cores. When the elasticity of the core material decreases to the initial position, they move mainly under the action of springs.

After removing the load from the cores of the half-mold, the divorce is. In this case, the mold 1 is moved to the left. Together with it, the plate is moved with ejectors 17, interrupted. precise sleeves with rods in them, as well as finished models 18.

The plate and the models are moved until the central ejector 19 touches the abutment (not shown in the drawings), after which they stop their movement, and the movable half-form continues to move further. As a result of this movement, the ejector slides along the sleeves 4, push the finished models into the bath with water.

Claims (2)

1.Press form on the author. St. 442008, characterized in that, in order to increase the durability of elastic cores, the movable half-form is provided with sleeves rigidly attached to it, covering two-step rods and having restrictive shoulders connected to the cores, the rods being spring-loaded with the possibility of longitudinal movement, and the rods' tips are flanged with restrictive shoulders connected to the cores from the side of the fixed floor. 2. A press mold according to claim 1, characterized in that the ends of the elastic cores are made in the form of cylindrical bridges with annular grooves of a rectangular shape, and the limiting sleeves of the sleeves and flanpts of the tips of the rods are provided with L-shaped projections. 9 10 16 Puz.f f015 fff / "/ J A / / 12 //