DE2238033C3 - Device for molding thin-walled hollow bodies - Google Patents

Description

is arranged and two cavities (22 and 23) ent-. ,. . ,,. ,

The invention relates to a Vomchtung

opening (34) of the mold or with a side for molding thin-walled hollow bodies,

from the chamber (2) outgoing pipe (25) and It is known to use a hollow cast piece with thin walls

on their lower end with each other and with 25 den by making a metal mold with the

a riser pipe (26) are connected, which in the melt of a metal, an alloy or a

Reaches into the furnace and fills its lower end into the synthetic resin that is in contact with the wall of the

Molten bath (14) is immersed, and on the other hand, a layer located in the form is cooled until it solidifies

Valve stopcock (4) comprising at least four pipes and then the excess of the melt removed

has, of which a first tube (41) to a 30 receives castings with thin walls equal-

Source of pressurized gas, a second tube (42) of moderate or variable thickness, e.g. B. hollow body, without

Gas volume 'es furnace, a third tube (43) using a core.

the side exit tube (25) of the compression The process is carried out in a craft-like manner

chamber (2) and finally ei:, fourth tube (45) applied, with the filling and emptying of the

nn the atmosphere is gas-free, and the 35 shape can be made by hand,

further at least one movable valve part The invention is based on the object of a

organ (rotor 46) contains. Device for molding thin layers

2. Device according spoke 1, characterized give Ge, the accurate control of the Wärmeaustaukennzeichnet that the riser pipe (26) is slanted position ULTRASONIC between a liquid material and the Sets. 40 walls of a shape and. «'. Dl for the automa-

3. Apparatus according to claim 1, thereby gc- tization is suitable.

indicates that the riser pipe (26) is perpendicular starting from a device such as that from the

is posed. British Patent 1,116,218 for casting

4. Apparatus according to claim 1, characterized in that pipes became known, is the subject of the invention that the compression chamber (2) 45 manure, with which this object is achieved, a device for molding vcn thin-walled hollow cores (211) and a device Bottom (212) comprising the pern carrying precise control of the heat build-up riser (26). between a molten material and

5. Apparatus according to claim 1, characterized in that the walls of a mold are allowed and that the compression chamber (2) is suitable for automation, has a heating means (215) open at its lower end, which has a setting and at its upper end End with gas outlet openings of the temperature of the compression chamber on as well as in its walls with at least one cool a temperature above that of the melting device provided form and allow a closed zen material to flow through it. Has low-pressure casting furnace, the crucible of which is a

6. Apparatus according to claim 1, characterized in 35 molten bath, the crucible of which is characterized by the fact that the two cavities (22 and inner volume of a gas under pressure occupied-23) of the compression chamber (2) is about the same men and below the have lower opening of the volumes. Form is arranged with the identification that it

7. Vot device according to claim 1, characterized on the one hand, a compression chamber, which indicates that the opening over which the two cavities of the mold and the oven is arranged and two of the cavities (22 and 23) at their lower cavities which are connected to one another at their upper end, one of the lower opening of the mold or with a laterally approximately the same cross-section as that of the riser pipe (26) extending from the chamber and at its section. lower end with each other and with a riser pipe

8. The device according to claim 1, characterized in that R _{5 is} connected, which extends into the furnace and indicates that the cavity (23) of the grain whose lower end is immersed in the molten bath, pressure chamber (2) at its upper, to the and on the other hand comprises a valve tap which has at least four pipes connected to the laterally occurring pipe (25), of which a first pipe

to a pressurized gas source, a second tube to the gas volume of the furnace, a third pipe to the side exit pipe of the compression chamber and then a fourth pipe is connected to the atmosphere, and the further at least one movable one Includes valve adjuster.

This VuUileinstellorgan is used during a first phase of the shutdown of the device securing the closing of all pipes, then during a second phase of filling the mold with the melt in the furnace of the compound of the first tube with the second tube, then during a third phase of solidification of the layer on the wall of the mold and the discharge of the excess shot of the melt from the mold into the furnace of the Connection of the second pipe to the third pipe and finally during a fourth phase of the Return of the unit consisting of the mold, the compression chamber and the furnace to atmospheric pressure the connection of the second, third and fourth pipe to one another.

The invention is explained in more detail with reference to the exemplary embodiments illustrated in the drawing show in it "

1 and 2 are summary sections d =: r unit consisting of the furnace, the compression chamber and the mold; According to FIG. 1, the melt is introduced at an angle, according to FIG. 2 vertical _right ~ ~

Fi'g.3 a section through the entire _processing Vorrich

F ie. 4 shows a section of the valve tap in its details

F i g. 5 a section of the compression chamber,

Fig. 9 to 9 sections of the device in the individual positions corresponding to the four phases _and

Fig. 10 to 12 show the use of the pouring device for the manufacture of a heater, FIG. 10 being a view of the heater. 11 shows a section along XI-XI of FIG. 10 and FIG. 12 shows a section through the upper half of the mold and the cast radiator in place

In the figures, the same parts are denoted by the same reference numerals.

The device for molding thin-walled

Hollow bodies comprises a furnace 1. a compression chamber 2 and a mold 3, which are arranged one above the other in the order mentioned, as well as a valve tap 4

The low-pressure casting furnace 1 contains a crucible 12, in a hermetically sealed housing is attached, which can be put through a gas supply pipe 13 under pressure. The bar increases that pouring materia, in the form of a water bath

"" The compression chamber 2 comprises a body 21 in which two internal cavities 22 and 23 are provided. The cavity 22 has an upper oil 6 ″, nune24 which is connected to an opening 34 which is located at the lower end of the mold 3. The upper part of the cavity 23 is connected to a tube 25 which emerges laterally from the body 21. In their lower part, the two cavities 22 and 23 are connected to one another and open into a riser pipe 26, the lower end of which is immersed in the molten bath 14 which is in the crucible

is included. The riser pipe 26 can be inclined (FIG. 1) or vertically (Fig. 2). ,

The chamber 2 is preferably made of Uuueisen of usual quality, such as is used for the production of metal molds for casting with gravity. It is dense and insulating coated inside with a ^w3ll ^ ^e "and fire-resistant coating of known type.

According to one shown in FIG. 5, the chamber 2 consists of two parts, namely the actual chamber body 211 and a base 212 which carries the riser pipe 26. The actual upper body 211 ends at its upper leu at its thermally resistant seal 213; this sealing surface as well as the one that connects the two parts of the chamber are completely smooth in order to allow the insertion of a pliable seal made of asbestos of very small thickness and thus more easily to ensure the desired seal and to create a seal that can be used at high temperatures. Heating systems 215, for example ducts or burners or electrical contradictions, are provided either on the outside of the body or in cavities 214 formed for this purpose in order to keep the whole thing slightly above the temperature of the melt used to pour the piece.

The two cavities 22 and 23, which the chamber 1 contains, can auiwei _sen approximately equal volumes. The opening through which they communicate at their lower end can be of the same! Cross-section like that of the riser pipe 26. The cavity 23 is provided at its upper end with a laterally bent evacuation tube 25 which runs through the Ventühahr. 4 can be blocked. The level of the melt must be below the connection point of this KcM-res 25. This point is controlled by an iicner lifting device which prevents further penetration of melt, for example in the event of a leak in the valve tap 4. If the material to be cast is an electrical conductor (e.g. in the fan of aluminum and its alloys), this safety device can be made up of two conductors 27 which, in the event of an excessive rise in its level, bring the molten material into electrical contact, which then about a nid. t.dargcstel tes solenoid valve closes valve tap 4

will. "," -, ··,

The shape of the cavity 23 is before?

conical so that the f ™ *? ™! * ¹ * position of the form is like this. that the £ J ^ surface is about 2 cm below the electrical contact, which in turn is about 2 cm below the tube 25. Die B «™ ¹ " ^ «"^;Vo'umens results from a simple application of the (3csctx.es from Manotte. vo, 1 of the m ** «v kn HUlhöheJer Torrn ^^^^^

men of the cavity 23, which is the highest, with the Device castable casting according to, and blcibl apparently for the smaller dimensions

valid. ■ ",,", "....

The mold 3 comprises a body 3t inside thereof

wall 32 an ^Innc ™ Y " ¹ " ™ " ³ * ^ J die _m i de rn his un'eren el die . ^önHm $ ™: J ^l i ™ _o ns upper opening 24 of the cavity 22 de, compression chamber 2 connected, st, and in its upper part air outlet ducts 35 ™ - _separated

This form consists of gctr

5 ^U 6

Molded parts together, which according to preferred levels, meiahns 4 are in connection, and the other pipes stcns horizontal and vertical plane aligned remain locked. Pressurized gas penetrates the lower ground and after checking the heat exchange pressure of 1, and the molten material be determined. rises in the riser pipe 26, enters the cavities 22

Some of these elements contain their own cooling circuits 5 and 23 of the compression chamber and reached 36 for the circulation of a fluid. Their assembly finally includes the interior 33 of the mold 3 (FIG. 7). the follows with the interposition of insulating heat - air previously contained in it escapes through the resistant seals or air ducts that form an air outlet ducts 35 which subsequently pass through the alignment the temperature gradient of the molten solidified metal are sealed. In cavity 23, zenen material that fills the mold, at the moment io which is closed by the blocked tube 43, the cooling and the onset of solidification under compressing the liquid material, e.g. B. the Legieder Effect of the respective cooling circuit of each molding melt the gas and the safety device part and so the formation of the desired skin 27 prevents any disturbance by softening it greater or lesser thickness depending on the penetration of the melt in the event of a leak in the Allow strength of cooling. 15 Valve tap 4 breaks off. A manometer shown in FIG. 5

The shape can be shown in foundry technology, can be provided in order to

ten components: Spindles to enable removable monitoring of low leakage losses.

Elements, guide jaws, slideways and In a third phase, the solidification phase

thrower. The outlet opening is in all cases where this is the layer adjacent to the mold wall and the

is possible, provided in a rounded shape, which ao draining the excess melt from the mold in

a slight removal of the excess metal and the furnace, the pressure is still required during the required

a quick closure of the casting by such a time for the formation of the solidified crust

glued or z. B. by frictional turning angc- the walls 32 of the mold 3 maintained. This

welded disc or by any other method the latter can be made by circulating a cooling fluid

ren enables. »5 are cooled, as shown in FIG. 3. after the

The various elements and components of the skin layer 30 on the mold walls 32 form the shape can with drive means such. B. Winding, has reached the desired thickness, the valve tap 4 be given away, which brought their separation during demolding in the position shown in Fig. 8: the and their assembly prior to casting. Pipes 42 and 43 are thus made possible with one another. 30 den, and the other pipes are blocked. It results

The air outlet ducts 35 are provided with a filter for a pressure equalization between the furnace 1 and

Deflating the air from the mold. This at the cavity 23, the gas escapes through this

known filter enables the flow of cavity into the mold and enables a return

Gas, however, prevents flow through the mold of the liquid material contained in the mold

filling melt due to its solidification. That 35 in the oven. At that moment the gas pressure is up

Filter can be made from drained, powderycm. grain in the plant from the surrounding atmospheric pressure

consist of primed aluminum oxide. still different.

The valve tap 4 comprises a hand body 48, in a fourth and final phase, the phase of the at least four tubes; in the illustrated return of the whole to atmospheric pressure. For example, he wears five, which are denoted by 41 to 45, the valve tap 4 is in the in F i g. 9, with the second tube and the fourth tube reversed in position; the pipes 43, 44 and 45 are connected to one another, the same role is played in connection with one another, while the pipes 41 and 42 are blocked, only because of construction convenience. The inside of the separated. The movable member of the valve furnace 1 and the cavity 23 are connected to the reversing valve is a rotor 46, which has a cutout 47 of air in connection, to which the pipe 45 leads, which is the mutual connection of various shapes opened, the casting allows 30 forth-pipes, pulled out as described in detail and the mold closed again,
will. The first pipe 41 is connected to a pressurized gas source. Then another manufacturing cycle can begin, e.g. B. air or nitrogen or any other All the processes described, including the neutral gas, connected, the second tube 42 and 50 opening and the closing of the mold, the moving and the fourth tube 44 are with the pressurized gas inlet pipe of all components, such as spindles, detachable 13 , which leads to the furnace housing 11, connected, the parts, slideways, ejectors, etc., the shape of the third tube 43 is connected to the tube 25 of the cavity can automatically according to a preselected pro-23 of the compression chamber 2, and the gram can be made what the production of the fifth tube 45 is finally available with the environment 55 makes every human intervention independent,
air in connection. It is recommended to use these as casting materials

The aim is now to describe the individual phases that have a low solidification temperature.

that make up a casting cycle. range (such as eutectic or weak

In a first phase, the so-called standstill alloy alloys), if one looks good

phase, all pipes of the valve tap 4 are blocked. 60 desires of the inner surface of the casting.

The cavity 33 of the mold 3, the cavities 22 and the device described is for manufacture

23 of the compression chamber 2 and the riser pipe 26 of any thin-walled casting are suitable. It

are empty and at atmospheric pressure (Fig. 6). be for example radiator elements, cover

The form can therefore be used for the processes of the upper hood. Housing, scaffolding, mechanical engineering elements,

surface preparation of the casting and demolding 65 such. B. pipes, plugs, z. B. engine blocks

be open. mentioned for heat-stressed engines.

In a second phase, the mold filling phase, the following is the production of an element 6

Form closed, the pipes 41 and 42 of the valve for a household radiator made of aluminum

alloy are described, the walls 66 of which define a central channel 61 and two lateral channels 62 and 63 (FIGS. 10 and 11). At their upper and lower ends the three channels are connected to one another by an upper channel 64 and a lower channel 65 and can be connected to the anal of adjacent heating body elements by means of four tubes, of which the two upper tubes 641, 642 and the two lower tubes 651, 652 lie in the middle area of the corresponding channel 64 and 65. The radiator element is cast with the lower end 653 open, but the tubes 641, 642, 651, 652 closed.

The upper part of the mold is shown in FIG. The parts of the mold which contact the parts of the radiator element whose walls have a very small thickness are not provided with coolants, while the parts of the mold which contact the parts of the radiator element whose walls have a greater thickness are provided with coolants . Accordingly, in the mold, the parts 3111, 3112, 3121, 3122, 3131 and 3132 that contact the thin walls 6611, 6612, 6621, 6622, 6631 and 6632 do not have a cooling system. In contrast, the mold parts 3141, 3142, 3151 and 3152, which contact the relatively thick walls 6641, 6642, 6651 and 6652 , contain cooling systems 3611, 3612, 3621 and 3622. The lower part of the mold is practically identical with the exception of parts 3111 and 3112 that do not exist below, because here the inflow and outflow openings are of circular cross-section for the melt.

Each molded part can be maneuvered separately by means of a pneumatic or hydraulic winch.

After casting with the device described and in accordance with the above explanation, the pipes 641, 642, 651 and 652 must be made according to the methods shown in FIG. Separate the planes 600 shown in FIG. 11 and close the open lower end 653 with a welded-on piece or adapter. In this way one obtains thin walls which

ao other processes impossible to produce, as well a maximum structural fineness without any casting defects, such as e.g. B. Blowholes, bubbles or the like Shrinkage cracks are greatly reduced.

For this purpose 2 sheets of drawings

409 635/22

Claims (1)

X 2 end and below the approach of this pipe Patent claims: with a safety device (Mj is provided, r pdje interrupts the penetration of the melt if 1. Device for molding thin walls- this reaches a certain level. ended hollow bodies, which have a precise control 5 9. Apparatus according to claim 8, characterized gedes Heat exchange between a molten characterizes that the shape of the cavity (23, zenen material and the walls of a mold also connected to the side tube (25) .st, can and is suitable for automation, a conical and its volume is such that be. theirs The lower end (34) is open and at its lower end (3) see the melt level with gas outlet openings (35) and half of that of the safety device (-7) their walls (31) with at least one cooling barrel is located. device (36) provided mold (3) and a 10. Use of the device according to a closed low-pressure casting furnace (1), the claims 1 to 9 for the production of a fcledessen crucible (12) contains a molten bath whose element (z. B. 6 ) of a household radiator.
The internal volume of a 15
Gas is taken under pressure and is arranged below the lower opening (34) of the mold. net is characterized in that
they on the one hand a compression chamber (2), the
between the mold (3) and the oven (1)