RU2015797C1 - Filling frame for pressing the moulds - Google Patents

Abstract

FIELD: foundry. SUBSTANCE: filling frame has walls 1 with slots. Movable members 2 are mounted in the slots. They project inside the frame due to flexible members 3. Movable members 2 are made in form of rotary sectors or variable-thickness plates. Frame is installed on the working table of machine 4 over the press plate 5. Movable members in form of plates interact with press plate due to templates 6. Members 2 are retained by stops 7 in extreme (countersunk) position. EFFECT: enhanced efficiency of casting. 3 cl, 2 dwg

Description

 The invention relates to foundry, in particular to equipment for the manufacture of foundry molds by static and pulse pressing.

 Known filling frame, the design of which is four smooth walls (GOST 17819-84). The frame is mounted on the flask to obtain an additional amount of the mixture and seal it in the flask. In lower pressing, the filling frame is located on the side of the mold.

 The main disadvantage of the molds made by pressing is the unevenness of the compaction of the mixture in height. The design of a conventional filling frame does not eliminate this drawback.

 The proposed design makes it possible to increase the efficiency of compaction by reducing the uneven distribution of the density of the mixture along the height of the mold. The uniformity of the seal is achieved by increasing the coefficient of lateral external friction. For this, the frame is equipped with movable elements protruding into the mixture into the frame. When approaching the press model plate, they are removed inside and do not interfere with pressing.

 Figure 1 and 2 presents the proposed filling frame options.

 The filling frame consists of walls 1, along the entire length of which or in separate zones (depending on the required density distribution over the cross section of the mold), slots are made. Movable elements 2 are strengthened in the slots. They enter the frame due to elastic elements 3, for example, springs. Using the same elements 3, the size of the protruding part of the movable elements 2 is regulated. The elements 2 themselves can be rotary sectors (Fig. 1) or plates of different thicknesses (Fig. 2). The frame is mounted on the work table of the machine 4 above the press plate 5. The movable elements 2 in the form of plates can interact with the press plate due to the copiers 6 (Fig. 2). In the extreme (recessed) position, the elements 2 are held by the latches 7. Elements 23 can also be installed in the flask.

 The filling frame works as follows.

 In the initial position, the elements 2 are in the extreme recessed position (flush with the walls), held by the latches 7.

 A flask is mounted on the frame and filled with molding sand. The latches 7 are retracted and the elements 2 are embedded in the mixture. The penetration depth is regulated by elastic elements 3 and depends on the properties of the mixture and the technologically necessary density distribution along the height of the mold. Elements 3 act on different sizes: the higher the element is located, the deeper it is embedded in the mixture.

 The lower pressing process begins. Thanks to the protruding elements, the external friction of the mixture against the walls increases. It prevents the free flow of the mixture up under the action of pressure. Because of what, the density of the mixture stabilizes along the height of the mold. Technologically necessary density is achieved primarily in the layers of the mixture directly adjacent to the pressing model plate. In the course of pressing the plate rises. When it reaches the front element 2 in the form of a rotary sector (Fig. 1), then it is gradually squeezed out to the side under the pressure of the compacted mixture until it is flush with the wall. In this position, it automatically snaps into place using latches 7. Thus, the element has taken its initial position and is ready for the next cycle of work. At the end of pressing, all elements 2 will be cocked and the filling frame is ready to receive a new portion of the mixture.

Elements 2 in the form of flat plates (figure 2) can not be retracted to their original position, like rotary sectors. Therefore, wedge copiers 6 installed on the pressing model plate 5 are used for their removal. Some complication of the structure compared to the scheme in figure 1 is compensated by the following advantages:
simplicity and low cost of reworking existing frameworks;
simpler design of movable elements 2 (plates instead of rotary sectors), they are easier and faster to manufacture, seal and test;
it is easier and more precise to adjust the depth of penetration into the mixture during pressing.

In general, the proposed framework designs (figures 1 and 2) allow:
to increase the uniformity of compaction of the mixture along the height of the mold, which improves the quality of the molds and the effectiveness of the compaction;
to regulate the density of forms in a wide range without readjustment of the press equipment, but only by changing the depth of introduction of moving elements;
accelerates the process of debugging the process when switching to a new model, because to determine the optimal density of the mold and distribute it along the height of the mold, it is not necessary to overload the entire equipment and the technological cycle, but rather to adjust the depth of introduction of the movable elements 2, which is much simpler.

Claims (3)

 1. FILLING FRAME FOR MANUFACTURE OF FORMS BY PRESSING, comprising a housing, characterized in that, in order to increase the efficiency of the seal, it is equipped with movable spring-loaded elements protruding into the housing and installed with the possibility of recession when exposed to a pressing mechanism.  2. The frame according to claim 1, characterized in that the movable elements are made in the form of rotary sectors.  3. The frame according to claim 1, characterized in that the movable elements are made in the form of plates interacting with the pressing mechanism by means of wedges or other copiers.

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