DE2627685A1 - Electrohydraulic casting core knockout appts. - with accurate positioning of electrode ensuring pulse energy acts directly on destructable body - Google Patents

Abstract

A liquid container is formed as a shell with a movable upper part telescopically jointed with a lower part. When the shell is extended, the space of the upper part supplements that of the lower part and connects with it. A pneumatic seal is provided on the joint between the parts. A casting support is rigidly fixed practically level with the upper face of the shell lower part. Also provided are a mechanism for delivering the casting, an electrode holder which can move the electrode to a preset position relative to the casting core, and a hydraulic cylinder for vertical movement of the shell upper part. Used in knocking-out cores from complex-shape castings, e.g. cores made with sol-glass mixts. and ferrochrome slags. Due to the visual control of the movement of the electrodes the energy of the pulse may be accurately directed.

Description

ARLAGE FOR EIEKPRORYDRAULIC TURNING OF THE APPNE FROM GUBSTUITS The present invention relates to the construction of locks, and more precisely to systems for electro-hydraulic knocking out of the core from castings.

The invention can be used for knocking out the cores from metallic castings Complicated configuration made of solid and difficult to knock out materials, e.g. Water glass mixtures with chemical hardening, graphitized or corundum mixtures with ethyl silicate binders are most effective.

Systems for electro-hydraulic systems are currently widespread Knocking out the cores from castings, consisting of a liquid koizb container and from at least one electrode holder on an electric hoist crane or a gantry crane above this container with the possibility of adjusting the electrodes in the specified Position is mounted with respect to the core of the casting. The facility comes with a Lifting mechanism for immersion of the Gugstück in the filled with water bahalter and for the following listening to take this Gugstücks out of this container fitted.

With the electrohydraulic knocking out of the cores from the Gagetück the property of electrical discharge is used, stoglines in the water, Some pressures in the bone, which is due to the electric charge, bow movements of liquid marshes under the action of the spreading vapor-gas plane in the zone of the discharge and the cavitation surge after the vapor-gas bubbles have disappeared to create.

All the listed phenomena create the conditions for destruction solid body, which is also used to knock the cores out of the cast pieces.

to the Glektrohydrsullachen knocking out the cores from the cast piece Dringt the electrode is placed over the cast piece and immersed in the water. Since the gugstückl covered with a layer of opaque liquid is an accurate one Placing the electrode over the core of the cast piece is difficult, and this works to reduce the quality of the work carried out.

It is also necessary to keep the electrode considerably large The length of the power supply cable should therefore be adjusted Dimensions at which the inductance of the Intladckkreis increases and significant current losses peel off.

Therefore one has tried, the plants in the direction of the honoring of the To improve the possibility of placing the electrodes over the learning in pieces.

For this purpose, attempts were made to use the system with a Equip manipulator and with the help of the Gu piece, above which one Electrode was arranged to be immersed in the water.

But it did not succeed, a completely synchronous immersion of Gugstück and Elsktroden, there was a shift in the Gugstück regarding the electrodes, and the length of the cables to be powered increased even more.

In addition, the mechanism of the manipulator turned out to be bulky, complicated to use and not reliable in operation.

For the purpose of perfecting the knees and eliminating them Wachtails was made by suent, the electrodes with the help of a keystroke with To arrange the fixing of the casting in the predefined position.

This also turns out to be impracticable in practice, since it is difficult is possible, cast pieces that are covered with a non-burnt-on molding mixture are, genan to il @ leron.

In order to separate off the test-fired layer of molding mixture on the casting beforehand and sprues and casting devices that enable precise fixation of the casting on the manipulator base prevent removal, an additional one is required. equipment and A large number of operating staff who needed this dirt and laborious work do not. In addition, you need a large number of harmful ions, which in turn sensor the work of the operator. But even if the above requirements orf2llt zind, the accuracy corresponds to the placement of @electrodes over the the castings do not meet the modern requirements of production technology, especially when it comes to small batch production of the casting with complicated Ronfiguration is changing.

Kalne of the systems that have become tezannied with a movable underframe for casting has been operating with precisely directed input of pulse energy to this day the electrohydric anti-charge on the core of the casting is guaranteed.

Inventors.

The investigations carried out have shown that the Destruction of the core and consequently also the knocking out of the basondurs then effectively are when the entire impulse.

energy in the form of emerging waves that cause destruction, is introduced into the cavity of the casting and onto the body to be destroyed, d. H. the core, acts directly.

The systems that have become known to this day are not capable of kernels to knock out of castings with a complicated configuration if the beads have a have no permanent strength of about 100 to 200 kg / cm².

In this case, the knocking out is repeated several times and the The rest of the core is removed from the cavity of the cast stubs with Help of a chopping hammer.

Ali that is with a significant increase in the cost of external locations Berne from castings, increasing energy consumption and an additional expense to tools and service personnel.

Increased in connection with the further development of mechanical engineering the need for castings with a complicated shape, which is of high quality Require cleaning of cores. <-> At the same time, the scope of Work on associated with cleaning the castings from the cores.

The use of water glass mixtures with rerrochrome slag aggregates in the production of cores brings the danger of a Sickness from silicosis, vibration sickness, and eczemonic cite as the atmosphere at the places where the cores were additionally knocked out of the castings with chopping hammers become heavily contaminated.

The problem of developing a system for electro-hydraulic Knocking out the core from the castings that meet the requirements of modern technology fair has become a current necessity.

The invention was based on the object of providing a system for electro-hydraulic Knocking out the cores from cast pieces with one such structural design of their roles to create, aie it allows the quality of the turning of the Rerne made of casting to improve the performance of the plant by directional Einiünrung the impulse energy in the cavity of the casting una at the same time a easy operation and reliability of the system to Gewäbrloistun.

This task was made possible by the development of a system for the electrohydraulic one Knocking out the cores from cast pieces released, consisting of a housing for the Liquid container, a @echanlsnus for feeding the Gugstück to the Underframes and the removal of this and at least one flektrodenhaitor, the one above this container with the Löglichkoit the idea of the electrode in the predetermined position is montisrt with respect to the core of the casting, in accordance with the Erilndung the container housing is provided with a movable upper part, the with the lower part of the housing is teksskop-like vsorbunden, the at their connection point has a compressed air lock, and that the cavity of the movable upper part of the container housing in the extended position as a supplement to the cavity of the lower part serves and connects to this and the base for the taste in one de upper end face of the lower part of the container housing substantially close to the elevation system is arranged and fixed immovably.

Such a constructive design of the plant that a movable one (lowerable) upper part of the container housing and a compressed air lock whose connection point has, ensures the required accuracy of the Arrangement of the electrodes over the grains of the casting as a result of visual observation the adjustment of the electrodes over the cores of the casting, which were fixed on the oiner Stage is located. This makes it possible to start the process according to the most favorable conditions genes directed introduction of the impulse energy on the core in the cavity of the casting to be carried out, whereby a high quality of the knocking is guaranteed, because the impulse energy acts directly on the body to be destroyed. Simultaneously With the improvement in quality, there is also a highlighting of performance and a reduction in electricity consumption is achieved. is also significantly simplified construction of the plant. It also reduces the length of the current to be fed cable and of the discharger.

The system is reliable and easy to use.

Thanks to a good overview, the visual guidance needs to be meaningful less time to anorun the eletrodes in the specified positions. The attachment is practically signed for knocking out the Aerne from castings with belietigr complicated Form both in small series and in mass production. in the first case the machine operator places the electrodes on himself in the shortest possible time / time often alternating types of castings. in the needs two folls the machine operator, after he has arranged the lead electrodes once, the location of the Electrodes for the entire own type series Gugteile / not to be changed.

To convert to a different series of castings, Maschinenf2rr just as little time as for retooling individual castings.

It is useful that the movable upper part of the container housing is so long that the upper forehead of this partially extended stables a value of about 0.6 m above the uppermost point of the cast piece arranged therein higher.

The specified length of the movable upper part of the container housing is sufficient to reduce the water ejection in the case of clever discharges. Elne Increasing the length is not advised, as it increases the length of the electrodes According to it, it is advantageous to have the lower part of the container housing with a bell-shaped Form section, the volume of the cavity of which is the volume of the cavity of the ejected movable in the upper part of the container housing, with it and connected to it flner pressurized air source, which guarantees the air supply in a kenge that leads to the displacing the liquid from the bell is continuously shaped section, the an air inlet valve and an air outlet valve.

By the presence of a bell-shaped section that is periodic is filled with liquid when the moving part of the Gohäusse is lowered and is located in the lower part of the container housing, and with air is filled when the movable upper part of the container housing is swept out upwards is and the liquid enters this, the filling and draining of the liquid out of the cavity through the movable upper movable part of the container housing in the lower part simplified.

The compressed air inlet valve ensures a quick filling of the Hobl space of the bell-shaped section with compressed air from a high-pressure network (about 5 to 6 atmospheres).

The compressed air release valve ensures a quick lowering of the liquid level in the cavity of the movable upper part of the housing, as the air pressure in this case is a maximum of 0.3 atm. One such constructive implementation of the bell-shaped Section in the plant for electrohydraulic knocking out of the cores does the Simple and reliable construction, as there are additional containers and mechanisms for the Pumping the liquid out of the cavity of the movable upper part of the container housing can be dispensed with prior to its lowering into the lower part of the container housing The bell-shaped section of the container housing can pass through the wall of the lower part of the container gohäuses and a vertical annular partition wall coaxial with this arranged wend and fastened in wesentlihen in the altitude at the upper end face is to be formed.

This is the constructively simplest implementation of the glookenfözmlgen Shutdown, sia does not require any additional space, as Eit is Kozpokt and is in the volume of the lower part of the housing fits well.

In addition, the passage cross-section of the annular opening is the the cavity of the bell-shaped section with the athletic space of the container housing connects, so great that it doesn’t give any @lurid for those to be displaced by the pressure of the air Fluid. This creates the required speed of displacement and overflowing the liquid back into the nchi space of the bell-shaped section guaranteed when the corresponding valves respond.

Next, the invention should be based on an exemplary embodiment of the plant for electrohydraulic knocking out of the cores from castings with reference to the boiling drawing will be explained in more detail. It shows on Fig. 1 the invention Plant in plan view: Fig. 2 the same plant in section with a vertical plane through the L2ngsachse, the Enlage for the electrohydraulic deflection of the Kekrne the housing 1 (Fig. 1) for the liquid container 2 (Fig. 2) with a movable upper part 3, which is connected to the lower part 4 of the housing is connected telescopically, is equipped. At their junction is a Compressed air lock 5 is provided. In the extended position of the Genäus 1 is used the cavity of the one part 3 as a supplement to the piling space of the lower part 4 and stands with him in pre-Uinaung. At a height that is essentially the Hönenlags of the upper end face of the Dntteils 4 of the housing 1 is approached Untergosteil 6 for the casting 7 rigidly attached.

The system is equipped with a mechanism 8 for feeding the casting 7 on the subframe 6 and equipped for taking it from the subframe 6.

Els mechanism 8 for the transport of the castings 7, which are on oinen door set 9 can be followed, a powered door carriage or a handle (not shown).

Eui pillars 10, which are used for the benched shell 3 of the üehässes as Serve guides, a Büane 11 is attached, the at least one electrode holder 12 carries, which is given with the kögilchkeit the adjustment of the electrode 13 in the Staliung with respect to the core 14 of the casting 7 is mounted.

The length of the movable upper part 3 of the housing is so chosen that deseon the upper m front side in the extended position the most possible point of the casting 7, which lies on the base 9, which is arranged on the untoz frame 6, at least towered over by 0.6 m. This will cause the liquid to be expelled from the lehäitor bui electrical discharges avoided.

The lower part 4 of the housing 1 woist a bell-shaped section 15 aui, the volume of which is equal to the volume of the hollow space that has been pushed out Upper part 3 of the container housing is nebulized and connected to dissem. The bell-shaped one Absannitt 15 has a Luitelnströmventil 16 and an air release valve 17 for the air that is gölsinet from a compressed air source (not shown). The compressed air source is so Gowänlt that sin the Luit under one pressure and in one Mange Liofurt, which is responsible for pushing the liquid coit out of the cavity of the bell-shaped Section 15 of the container housing 1 and for deron zuunt in the nohlraum doe movable Upper part 3 of the container gene 1 is sufficient.

The bell-shaped section 15 is through the turn of the lower part 4 of the Echaltergehäuses 1 and by a vertical annular partition 18, the Runed coaxially to the diuser wall and attached to the upper end of the wall in the mönenlage is delimited. The drive for pre-clipping the movable upper parts 3 of the container housing contains a hydraulic cylinder 19, which is connected to it by means of a rope pulley 21 suspended meiles 20 is connected.

For the continuous removal of the sludge that occurs in the event of destruction the core 14 of the casting 7 accrues, a centrifugal sludge pump 22 is provided, those on the tapering Boasnteil of the container housing 1 and on a hydraullschen Zyklon 25 is connected.

The electro-hydraulic equipment is in a soundproof room with Zlegelstein- or Eaton walls 24 erected in the breakthrough 25 with flaps 26 are closed.

The machine operator's workstation 27 is outside the electrohydraulic system on a control panel 28 in front of which the window 29 for visual observation of the adjustment of the electrodes 13 and the operation of the system.

The electro-hydraulic system for knocking the cores out of castings is operated as follows.

the casting 7 (Fig. 1) is placed on the base 9 so that the no outlets 14 (Fig. 2) face the electrodes 13. l through a splice Arrangement of the casting 7 is the best possible knocking out of the cores from the casting 7 thereby enables the impulse energy to act on the core body 14 is directed. The base 9 with the casting 7 is with the aid of a bridge crane (not shown) em mechanism 8 fed, which the base 9 with the Casting 7 transported to the system. The machine operator lifts from the control panel 28 (Fig. 1) from the flaps 20 (Fig. 2) and opens the openings 25. At the same time turns on the drive 19 and leaves the movable upper part 3 of the Benältgehäuses with the help of the ropes 20 suspended on pulleys 21 in the lower position. With the aid of the mechanism 8, the base 9 with the casting 7 is then placed on the Underframe 6 transported, after which the mechanism 9 <in the starting position> is returned to the acceptance of the next casting 7 <->.

He arranges the electrodes 13 from his control panel 28 (FIG. 1) (Fig. 2) on the exit points of the cores 14 in the casting 7 and observed the process through the window 29 (Fig. 1) visually.

then he switches drive 19 (ilg. 2) to lift the bed Upper part 3 of the container housing 1 ain and at the same time leaves the flaps 26, the close the openings 25, machine operator down. Then it starts the compressed air flow into the cavity of the compressed air lock 5, which is the location of the tele-part Scope-like connection of the upper 3 and the lower part 4 of the container housing 1 seals. He opens the valve 16 and the compressed air flows from the compressed air source (not shown) in the honlraum of the bell-shaped section 15 by they the liquid from the cavity of the bell-shaped section 15 into the cavity of the movable upper part 3 of the container housing is displaced.

That displaced from the hobl space of the cam-shaped sections 15 Volume of the liquid ensures the transfer of the liquid level above the top point of the casting 7 by a value of about 0.6 m, after which you can Air inlet valve 16 closes.

thus all preparatory work for commissioning the system completed and the machine operator switches the supply of voltage off Generators of the current pulses (not shown) to the electrodes 13 a.

Spark discharges occur between the electrode 13 and the casting 7, which the destruction of the core 14 by the formation of high pressure zones and shock waves cause.

The core 14 is knocked out by serial pulse discharges. after the end of the deflection process one switches to the signal of a program pulse counter On em Stener desk 28 (Fig. 1) the high voltage opens, the valve 17 (Fig. 2) opens and the compressed air is released from the bell-shaped section 15 under the action of the hydrostatic liquid column in the bonl space of the daily upper part 3 dos Bonaltergahätseß pushed out.

The pebble of liquid winds in the cavity of the sized upper part 3 of the container housing up to the output level below the level of the subframe @ derabgenstit.

Then you can release the lait from the compressed air lock 5, switches on the drive 19 and leaves the movable upper part 3 of the container housing down. At the same time men lifts the flaps 26 and opens the openings 25. The machined casting 7 is with the base 9 from the plant by means of de Lochanism 8 removed, after which the system for knocking out the grains from the next Cast 7 is over, and the game repeats itself.

Ju me to the fouling of the liquid coit by the particles of the destroyed Cores are closed by the device for the continuous removal of the sludge by means of the pump 22 (FIG. 2) and the hyaraulic cyclone 23. The repatriation of sewage water in the tank is provided, thereby reducing water consumption and the plant become more economical operations.

All enumerated operations can be performed in both automatic as can also be carried out in manual mode, with the assumption that the Electrodes at the specified casting points, what the machine operator with visual Observation.

In control circuits, blockages are provided which ensure a complete The control system is safe for both automatic and manual operation guarantee.

The electro-hydraulic system for knocking out cores from castings can be designed as a through or as a one-sided reversing system.

The system was tested and confirmed under production conditions file cine good deflection quality, the possibility of convenient set-up and Operation as well as reliable and trouble-free operation of all mechanisms.

L e r s e i t e

Claims (4)

P A T E N T A N S P R Ü C H E 1. Attachment to the electro-hydraulic Knocking out the core from castings, test hand from a housing for the liquid container, a mechanism for feeding the casting onto the subframe and removing it from this and from at least one electrode holder, which is above this container with the possibility of varpositioning the electrodes in the predetermined position with respect to of the core of the casting is mounted, so a u r e a g e k e n fl z e L c h n 6 t that the container housing (I) is provided with a movable upper part (3), which is telescopically connected to the lower part (4) of the housing, the Connection point has a compressed air seal (5), and that the iiohlraum des movable upper part (3) of the container housing in extended position as a supplement to the cavity dos our part (4) serves and connects to this, and the underframe (6) for the Gugstück (7) in one of the upper end faces of the lower part (4) of the container housing (1) is arranged substantially close to altitude and is fixed immovably. 2. Plant according to claim 1, d a d u r c h g e k e n n -z e i c h n e t that the length of the movable upper part (3) it container housing (1) is chosen is that its upper face in the extended position the highest point of the Casting (7), which is housed in the intestine, protrudes by a value, represent is very close to 0.6 m. 3. Plant according to claim 1, d a d u r c h h e k e n n -z e 1 c h n e t that the lower part (4) of the container housing (1) has a bell-shaped section (15), the cavity volume of which corresponds to the cavity volume of the pushed out movable upper part (3) of the container housing (1) approaches, with this and with a compressed air source connects the Luitzuyuhr in one length, to displace the liquid (2) from the bell-shaped section (15), the an air inflow valve (16) and an air release valve (17) are required is. 4. system according to @ claim 3, d a d u r c h g e k e n n -z e i c h n e t that the bell-shaped portion (15) of the container housing (1) through the Wall of the lower part (4) of the container housing (1) and a vertical annular Partition wall (18) which is arranged coaxially to this wall and essentially at in the height of which the upper face is attached, is formed,