EP3585537B1 - Apparatus and method for destroying a casting core - Google Patents

Description

The invention relates to a device and a method for destroying a casting core of a cast workpiece, the device having at least one hammer or at least one hammer being used to destroy the casting core. The invention also relates to a device and a method for removing parts of a casting core that adhere to the workpiece.

To destroy a cast core or to remove the core / sand from workpieces that have been manufactured by means of a casting process, the workpieces can be made to vibrate by hitting them with a hammer, whereby the core is shattered and, if necessary, molding sand is removed from the workpiece.

A device and a method of the type mentioned are, for example, from DE10136713 A1 known, which discloses pneumatic knocking devices for the destruction of a cast core.

the GB 2067938 A discloses a device for destroying a casting core or for desanding workpieces, a hydraulic hammer being used as a hammer. The device has a hydraulic hammer arranged on the carrier frame, the hydraulic hammer being fastened to a holding device arranged on the base frame of the carrier frame. Furthermore, the holding device of the hydraulic hammer is mounted displaceably on a guide arranged on the base frame.

the EP 0304683 A2 shows a method and apparatus for removing inner cores from castings. The casting is held on a machine table (knocking table) by means of a holding or clamping device and then a wall part of the casting is knocked with the plunger of a hydraulic hammer. Furthermore, after "knocking" the casting is conveyed onto a vibrating table in order to let the molding sand trickle out of the openings of the casting, the casting being rotated about at least one axis during the trickle or shaking vibration.

Further relevant devices are from the U.S. 4,643,243 A and the WO 2014/056014 A1 known.

The use of pneumatic hammers to destroy a casting core is associated with a number of disadvantages, in particular with the disadvantages listed below:
Depending on the design, a pneumatic hammer must be operated with oiled compressed air, which is blown off into the environment after the blow has been executed. The oil in the exhaust air, which is at least partially blown in the direction of the workpiece or the casting core / the casting mold, contaminates the workpiece and the molding sand. On the one hand, this makes further processing of the workpiece more difficult, since it usually has to be cleaned before further processing steps; on the other hand, further or reuse of the molding sand is restricted or even prevented in the long term due to the contamination with the oil. This is accompanied by environmental problems, since the molding sand has to be disposed of in a laborious manner.

In addition, the finely atomized oil in the exhaust air aerosol also pollutes the ambient air, which results in health problems for those in the vicinity of the coring device. In addition, after a short time, an oil film is deposited on the coring device itself and on the devices and machines arranged in the vicinity of the coring device. This can trigger malfunctions of the affected devices / machines, but at least this results in increased effort for cleaning the soiled surfaces.

Furthermore, a pneumatic hammer can only be pressed against the workpiece with a comparatively low pressing force. When using a pneumatic hammer, additional clamping devices are therefore usually required to prevent the workpiece from "wandering" on the machine table.

In addition, a blow in pneumatic systems takes a relatively long time. In pneumatic systems, the excitation of transverse and longitudinal waves in the workpiece is therefore carried out with a comparatively low energy density.

In addition, pneumatic hammers generally show a tendency towards an undesirable decrease in the impact frequency under load. Due to this decrease in the impact frequency, the desanding / gutting performance that can actually be achieved is reduced compared to the desanding / gutting performance that can be achieved nominally.

In addition, the heat dissipation from a pneumatic hammer is comparatively poor, so that breaks must be scheduled regularly during operation of the pneumatic hammer, which allow the pneumatic hammer to cool down.

Furthermore, pneumatic hammers have a comparatively short service life and often have to be serviced. Due to the frequent maintenance intervals, productivity is comparatively low.

In addition, with the pneumatic hammer, positioning of the chisel and a controlled end position cannot be achieved without special measures. This is particularly problematic in the case of automatic processing sequences.

After all, pneumatic hammers are comparatively large. Machining small workpieces in particular can therefore be problematic.

It is therefore an object of the invention to provide an improved device and an improved method for destroying a casting core. Furthermore, a device and a method for removing parts of a casting core adhering to the workpiece are to be specified. In particular, the above-mentioned disadvantages of the prior art are to be overcome.

This object is achieved according to the invention by a device according to claim 1 of the type mentioned at the outset in that the at least one hammer is a hydraulic hammer.

The object of the invention is also achieved by a method according to claim 9 of the type mentioned at the outset, in which at least one hydraulic hammer is used to destroy a cast core and / or to remove parts of a cast core adhering to the workpiece.

In the context of the invention, “destruction” of a cast core is primarily understood to mean breaking the cast core or causing cracks in the cast core. The broken cast core can then be removed from the workpiece, for example with the aid of a vibrating device, by further destroying the cast core and breaking it up into such small parts that the cast core is ultimately discharged from the workpiece. One then speaks of (complete) "coring or desanding".

This "coring or desanding" is not necessarily done by a vibrating device, but can also be done by the disclosed device for the hydraulic destruction of a casting core. The "destruction" of a casting core then also includes the (complete) "coring or desanding".

A "mold" is a body that is negative in shape to the desired shape of the workpiece.

A "casting core" is a special case of a casting mold which forms a cavity in the workpiece or an inner contour of the workpiece.

"Molding sand" is the material from which a casting mold and, in particular, a casting core is made. Even if mostly sand with a binding agent is actually used for the production of casting molds / casting cores, the term "molding sand" in the context of the invention also includes other substances that are used for the production of casting molds / casting cores . Alternative terms for "molding sand" are "model sand" or "molding material". Alternative molding materials are, for example, salt or ceramics.

Casting molds / casting cores can have different grain sizes of sand. In addition, casting molds / casting cores can be bound with different binder systems, for example with inorganic binders (e.g. water glass) or organic binders (e.g. resins). Cast cores can also have different densities and / or molded material properties. In addition, further substances or bodies can be incorporated into the cast cores, for example core iron. Cast cores that are hollow or partially hollow on the inside can also be produced, for example by providing an opening or a plurality of openings in the cast core or by the casting core consisting of several parts.

Casting cores with different densities and / or different molding material properties can be produced, for example, by printing. When printing molding materials, the properties of the casting core can be determined locally by varying the binder. For example, casting cores with a solid shell and loose sand volume inside can be produced in this way.

Cast cores can, for example, also be produced with a core shooting machine ("shot cast cores"). Here, the molding sand is injected into the core box at high speed, for example with the aid of a sudden expansion of a volume of compressed air. Both moist and dry molding materials can be shot into cold core boxes ("cold box method") or hot core boxes ("hot box method").

Cast cores and their molded parts can, however, also be produced using the molded mask process, for example. The molding sand, which is coated with a dry binding agent, is poured onto a heated model plate. Due to the binding agent softened by the heat, the molding sand bakes together to form a layered casting core. With this core molding process, very strong and also internally hollow cast cores can be produced.

The casting cores produced with molding sand (or their molded parts) can be coated or infiltrated with materials in order to create improved properties compared to the melt, such as improved wetting, higher temperature resistance, as well as improved gas permeability, porosity or gas tightness (see also "Sizing") .

The presented device according to claim 1 and the presented method according to claim 9 are suitable for destroying and in particular also for removing all known types of casting cores, in particular for destroying / removing the types of casting cores listed above.

In the proposed method, the at least one hydraulic hammer is (also) used to remove parts of the cast core adhering to the workpiece.

"Adhering parts" of a casting core to the workpiece are those parts of the casting core which, when the casting core is destroyed, detach themselves from the rest of the same, but not from the workpiece without any further influence. These parts form during the casting process in the boundary layer between the workpiece and the casting core, in particular due to the high temperatures that occur. "Adhering parts" of the casting core are in particular "sizing" and "penetrating molding sand".

In the field of foundry technology, "size" is a coating material that is applied to a casting mold or a casting core in order to smooth the surface of the porous molded part. Finely ground refractory to highly refractory materials are used as the base material. The coating layer insulates the base material of the casting mold or the casting core (i.e. the molding sand) and protects it from excessive thermal stress from the molten metal. During the casting process, the coating can "stick" to the workpiece.

In foundry technology, "sand penetration" refers to the penetration of molding sand into the workpiece or sand deposits on the cast part, which lead to rough cast surfaces. Grains of sand are partially or completely enclosed by the material of the workpiece. Workpieces made of aluminum are mainly affected by this undesirable phenomenon, but it can also occur with other materials. The term "sand penetration" not only describes the process, i.e. the penetration of the molding sand into the workpiece surface, but also the penetrating molding sand itself. "Sand penetration" is therefore also to be understood as molding sand adhering to the workpiece.

In principle, the proposed device and the proposed method can be used to destroy only the casting core, which may include (complete) coring / desanding of the workpiece, only removing sizing from the workpiece, only removing sand penetration or performing a combination of the listed types of processing . Combined types of processing can be carried out simultaneously or at the same time or one after the other in separate processing steps. For example, the core / desanding of the workpiece can be carried out in a first step and the coating can be removed in a separate, second processing step.

Destroying the casting core can also include destroying a casting mold (which has a cavity or depicts an outer contour of the workpiece). Likewise, the coring / desanding of the workpiece can also include the removal of a casting mold (having a cavity or depicting an outer contour of the workpiece). In addition, removed sizing or sand penetration can also originate from a casting mold (which has a cavity or depicts an outer contour of the workpiece).

The use of a hydraulic hammer results in a number of advantages, in particular the advantages listed below:
In contrast to a pneumatic system, a hydraulic system has a closed circuit from which the oil does not escape during normal operation. The further processing of the workpiece is therefore made easier, since it does not have to be degreased, and The molding sand can also be reused or reused in the long term, so that it only has to be disposed of after many cycles.

In addition, the environment of the coring device is not polluted with the oil contained in the compressed air. Damage to health as well as malfunctions and increased cleaning effort, as they can be caused by compressed air systems, are not given with the hydraulic system.

As a rule, the hydraulic hammer also has a comparatively high impact weight with a relatively small stroke. Due to the higher prevailing pressures in the hydraulic system, the hammer is nevertheless strongly accelerated and hit against the chisel of the hydraulic hammer with great force. The high pressures and the associated high forces mean that the chisel of the hydraulic hammer can be pressed against the workpiece with a comparatively high contact force. The contact pressure for the hydraulic hammer is advantageously more than 2 kN, whereas the pneumatic hammer can generally only be pressed against the workpiece with less than 1 kN. When using pneumatic hammers, additional clamping devices are therefore usually required in order to prevent the workpiece from "wandering" on the machine table. When using hydraulic hammers, however, no further clamping devices are required. In other words, a clamping force is preferably transmitted to the workpiece exclusively with the at least one hydraulic hammer, which also destroys the cast core or removes adhering cast core parts from the workpiece. In other words, the device preferably has the hydraulic hammer as the only contact element for pressing the workpiece against the machine table of the device, which is also set up to destroy the cast core or to remove parts of the cast core adhering to the workpiece. The clamping force is preferably transmitted to the workpiece by the at least one hydraulic hammer during the entire machining process.

It is also advantageous if only the at least one hydraulic hammer is provided for generating a clamping force acting on the workpiece. This means that the hydraulic hammer does not only act as a single contact element for pressing the workpiece against the machine table, but it also generates the clamping force. A separate hydraulic cylinder for generating the clamping force can then be omitted.

Furthermore, the workpiece is preferably clamped with a force of at least 2 kN per hydraulic hammer in the device for destroying the cast core or removing the cast core parts adhering to the workpiece.

Due to the high clamping forces and the associated compression of the workpiece, the vibration behavior of the workpiece itself and also the vibration behavior of the system, including the workpiece and the processing machine in which the workpiece is clamped, is significantly changed, which results in the destruction of the cast core or the removal of Cast core parts adhering to the workpiece are positively influenced. In general, the hydraulic hammer stimulates the workpiece over a wide range, not least through wave reflections on the machine frame of the processing machine in which the workpiece is clamped.

Research has also shown that using hydraulic hammers requires less energy to achieve the same desanding / ginning performance than using pneumatic hammers. Calculations reveal that the hydraulic system only needs 18% of the energy required for coring that the pneumatic system needs for the same sanding / gutting performance. In another experiment it was found that 2 hydraulic hammers provide the same desanding / gutting performance in 15 seconds as 6 pneumatic hammers in 60 seconds. This means that the time required for desanding / gutting or the energy required for this is significantly reduced by using the hydraulic hammer.

This surprising result is mainly attributed to the fact that the mechanical impulse that is transmitted from the hammer to the chisel is significantly higher when using a hydraulic hammer than with pneumatic systems. In addition, the moving liquid column, which forms in the supply line to the hydraulic hammer when the pressure oil flows into the cylinder of the hydraulic hammer, practically runs into a rigid obstacle and therefore becomes too strong due to the incompressibility of the hydraulic oil Excessive pressure occurs, which intensifies the blow. In other words, the weight of the moving column of liquid can be added to the impact weight. The moving gas column that forms in the supply line to the pneumatic hammer when the compressed air flows into the cylinder of the pneumatic hammer, on the other hand, has practically no weight and the air can also be compressed. There is therefore no additional effect due to the pressure medium in the supply line in pneumatic systems. The flow behavior of the pressure medium into the cylinder should also be better with hydraulic hammers and be associated with less turbulence than is the case with pneumatic hammers.

In addition, the impact in hydraulic systems is very short, which is also due to the incompressibility of the pressure medium. This means that the energy transferred from the hammer to the chisel is concentrated in time. In other words, the energy is transferred to the bit in a very short period of time. This results in high power peaks over time. In contrast, the energy transfer in pneumatic systems is relatively slow, which means that power peaks do not result. The excitation of transverse and longitudinal waves in hydraulic systems therefore takes place with a higher energy density than in pneumatic systems. When using hydraulic hammers, stronger transverse and longitudinal waves are formed in the workpiece than is the case with pneumatic systems. Therefore, the desanding performance or removal performance of adhering cast core parts is significantly greater in hydraulic systems than in pneumatic systems with the same amount of energy used.

As mentioned, the strongly pronounced transverse and longitudinal waves in the workpiece also cause adhering parts of a cast core to break off when the hydraulic hammer hits the workpiece, which simplifies the subsequent machining of the workpiece. In particular, the desanding / core removal of the workpiece and the removal of parts adhering to the workpiece can take place with one machine and in one clamping of the workpiece. This can significantly reduce the time it takes to manufacture a cast product. When using pneumatic hammers, for example, the coating is removed using other methods, for example shot peening (for example with steel balls with a diameter of 1 mm). This means that another machine is required and the workpiece has to be clamped.

For the reasons mentioned, the blow performed by the hydraulic hammer preferably does not take place on the molding sand of the casting core or the casting mold, but on the (usually metallic) workpiece. The impact is therefore particularly hard or particularly short and energy-intensive. In this case, the chisel advantageously does not have a point, but is flattened.

The impact duration must not be confused with the impact frequency. With the same beat frequency, completely different beat durations can exist (of course the beat duration is always shorter than the period duration of the beat frequency). This also means that shorter beats with the same average energy content over a period have a higher energy density than longer beats.

Pneumatic hammers generally also show a tendency towards a decrease in the impact frequency under load, whereas the impact frequency in hydraulic hammers remains essentially constant even under load. A higher impact frequency means, in turn, higher desanding / coring performance or higher rates when removing parts of the casting core adhering to the workpiece. In the pneumatic and hydraulic hammers examined, the impact frequency for pneumatic systems is around 20-25 Hz, whereas the impact frequency for hydraulic systems is around 28-45 Hz.

Another advantage of the hydraulic system is that oil is a much better heat transfer medium than air. The heat capacity of oil is typically around 1.7 kJ / (kg · K) and of air around 1.0 kJ / (kg · K). This means that the resulting heat can be dissipated better by a hydraulic hammer and that it can be kept cooler than a pneumatic hammer. For example, the oil returning from the hammer is fed to an oil cooler for this purpose. Due to the better heat dissipation, a more favorable pulse-pause ratio can be achieved. This means that the hydraulic hammer can be in operation proportionally longer than a pneumatic hammer in a given period of time. The hydraulic hammer can therefore process more workpieces than a pneumatic hammer in the same time for this reason.

In addition, hydraulic systems generally also have a longer service life overall, so that maintenance intervals can be extended compared to pneumatic systems.

Furthermore, due to the higher energy density of the pressure medium in hydraulic systems, a hydraulic hammer is smaller than a pneumatic hammer and is usually also more slender than a pneumatic hammer with the same desanding / coring performance or the same rate of removal of cast core parts adhering to the workpiece. This is particularly advantageous when machining cast engine blocks, since hydraulic hammers can be arranged relatively closely and, in particular, at a distance from the cylinder bores in the engine block to be machined. With the ever smaller cubic capacity, the use of a hydraulic hammer is a particular advantage in this regard.

Finally, because of the incompressible pressure medium, the position of the chisel and in particular its end position in the hydraulic hammer can be very well controlled or adjusted by the volume of the inflowing oil. With the pneumatic hammer, on the other hand, positioning the chisel and a controlled end position cannot be achieved without special measures.

It is generally advantageous if a plastic plate is inserted between the workpiece and a machine table of the device for destroying a casting core / removing parts of the casting core adhering to the workpiece. This plastic plate is used for damping, which prevents the impact energy from being conducted into the machine frame of the device in which the workpiece is clamped. Instead, the energy is dissipated directly in the workpiece and used there for the destruction of a cast core / removal of parts of a cast core adhering to the workpiece. By providing the plastic plate, high vibration amplitudes can advantageously also be generated in the workpiece, which promote the destruction of the cast core / removal of parts of the cast core adhering to the workpiece. An example of such a plastic plate is known under the trade name PU-Tecthan 556 and has a hardness of 95 Shore A.

In principle, however, the base can also be made of steel. This leads to very little damping and is dependent on the casting geometry and the contact surface advantageous if very high-frequency vibrations are to be generated on the component. By providing the steel plate, too high vibration amplitudes in the workpiece can advantageously be avoided, for example in order to prevent the breaking off of widely protruding workpiece parts and / or the undesired breaking off of sprues.

It should be noted at this point that the specified variants and the advantages resulting therefrom each relate to both the destruction of a casting core of a workpiece and the removal of casting core parts adhering to the workpiece, even if this is not always explicitly stated. Therefore, a method and a device for destroying a casting core can also be used to remove the parts of the casting core adhering to the workpiece, and vice versa, unless otherwise specified.

With regard to the destruction of a casting core of a workpiece or the removal of parts of the casting core adhering to the workpiece, it has been found to be particularly advantageous if the hydraulic hammer is operated with an impact frequency between 750 and 2700 impacts per minute (or more preferably between 1700 and 2700 impacts per minute) and / or an operating pressure between 100 and 150 bar and / or a hydraulic oil flow between 12-35 1 / min. In these areas, the destruction of a casting core or the removal of parts adhering to the workpiece works particularly well.

According to an advantageous variant of the invention, it can be provided that the device has at least one support frame on which the hydraulic hammer is arranged. This variant of the invention is characterized in that a defined position of the hydraulic hammer in relation to the workpiece to be machined can be reliably guaranteed.

In an advantageous development of the invention, it can be provided that the hydraulic hammer is attached to a holding device arranged on a base frame of the support frame.

In order to be able to set an optimal distance from the workpiece, it has also been found to be advantageous for the holding device to be displaceably mounted on a guide connected to the base frame, in particular on a guide rail.

It has been found to be particularly favorable here that a longitudinal extension of the guide or guide rail runs vertically to an installation plane of the support frame. In this way, the distance between the hammer and a workpiece arranged underneath can be set very precisely in a simple manner.

In order to change the position of the hydraulic hammer, it can be provided that the holding device is connected to at least one actuator arranged on the base frame. The at least one actuator can be, for example, a hydraulic or pneumatic or hydropneumatic or electromechanical actuator. In order to enable very precise control, it can be provided that the actuators are controlled servohydraulically or digitally hydraulically.

However, it has proven to be particularly advantageous if the at least one actuator is designed as a piston / cylinder unit, in particular as a hydraulic cylinder.

In order to be able to achieve a low overall height and a compact structure, a piston of the piston / cylinder unit can be fastened to the holding device and a cylinder to the base frame, or vice versa. This arrangement of the piston / cylinder units makes it possible to achieve a low overall height for the coring device. Preferably, the piston pushes the hydraulic hammer up (the oil pressure acts on the entire circular cross-sectional area of the piston) and pulls it down (the oil pressure acts on an annular piston surface). As a result, high forces can be generated when lifting the hydraulic hammer and that structure of the coring device to which the hydraulic hammer is attached. Due to the weight of the hydraulic hammer and the structure of the coring device to which the hydraulic hammer is attached, high contact or clamping forces can also be achieved on the workpiece, even if the oil pressure only acts on the annular piston surface.

The transfer of energy to the core can be further improved in that the device has several hydraulic hammers, or several hydraulic hammers are used for the core removal process. The striking movements of these hammers can in particular be synchronized, for example phase-shifted with respect to one another, as a result of which the energy transmission can be further improved. For this purpose a controller be provided, which is set up to control several hydraulic hammers in a synchronized manner.

It is also advantageous if a clamping device for a workpiece is arranged in the active area of the at least one hydraulic hammer or can be moved there. In this way, the workpiece can be fixed during processing. If the clamping device can be moved into the active area of the at least one hydraulic hammer, then the clamping of the workpiece can be decoupled from the machining with the at least one hydraulic hammer, which simplifies the core removal process. In this case, the loaded clamping device for machining is moved into the effective area of the at least one hydraulic hammer and, after machining, is moved out of this again. In general, it should be noted that the use of a clamping device does not exclude additional clamping, in which an additional clamping force is transmitted to the workpiece with the at least one hydraulic hammer. In particular, the clamping force is again more than 2 kN per hydraulic hammer.

It is also part of the invention when the clamping device is arranged on a belt or a chain or a rotary table. In this way, the coring device can be continuously loaded with workpieces.

It is also particularly advantageous if the device for destroying a casting core / removing the parts of the casting core adhering to the workpiece has at least one first position in the effective area of at least one first hydraulic hammer, to which the clamping device can be moved, and at least one second position in the effective area a second hydraulic hammer to which the clamping device can be moved. Accordingly, the clamping device with a workpiece can be moved to a first position, where the workpiece is machined with at least one first hydraulic hammer, and then moved to a second position, where the workpiece is machined with at least one second hydraulic hammer. For example, the device can have several processing stations, each with a hydraulic hammer or several hydraulic hammers, to which the clamping device or the workpiece clamped therein can be moved. With the aid of the belt, the chain or the rotary table, a clamping device can be moved to a first position in the effective area of a first processing station with first hydraulic hammers and processed there. In a further work step, the clamping device is moved to a second position in the effective area of a second processing station with second hydraulic hammers and processed there.

It is also particularly advantageous if the first guide or guide rail is aligned in the direction of movement of the belt / chain or is arranged in the area of movement of the rotary table. As a result, the at least one hydraulic hammer can be moved uniformly with a clamping device, for example with the aid of the actuator. The movement can be translatory and / or rotary. In this embodiment, the belt / chain or the rotary table moves continuously, and the machining stations or their hydraulic hammers move uniformly with the clamping device while the workpiece is being machined (i.e., for example, when executing an impact or also during a clamping movement). After machining, the machining station retracts and the cycle starts again. However, it is also conceivable that the belt / chain or the rotary table moves discontinuously and stops at a position where the workpiece is being machined. In this case, the processing stations or their hydraulic hammers can remain in one (processing) position.

If a rotary table is used, the processing stations can be mounted on two horizontal guide rails and execute a circular path with the help of superimposed movements. However, it is of course also conceivable for the machining stations to be rotatable about the vertical axis about which the rotary table is also rotatably mounted, so that uniform movement of the machining stations and the clamping devices is possible.

It is part of the invention when the clamping device is coupled to a vibrating device or is arranged on this. As a result, the workpiece is not only machined with the aid of the at least one hydraulic hammer, but is also shaken, which improves or accelerates the core removal process.

It is also advantageous if the at least one hydraulic hammer is between a working position in which a workpiece clamped in the clamping device is located in the effective area of the at least one hydraulic hammer, and a rest position in which a workpiece clamped in the clamping device is outside the effective area of the at least one Hydraulic hammer is located, is movable or is moved. In particular, the at least one hydraulic hammer can be shifted or pivoted for this purpose. In this way, the at least one hydraulic hammer can be brought into the working position for machining the workpiece and, after machining has taken place, into the rest position, for example to enable access to the clamping device. It is also conceivable that the at least one hydraulic hammer is moved into the rest position when the workpiece is being processed in some other way, for example shaken and / or rotated.

It is also part of the invention when the clamping device is mounted rotatably about a horizontal axis of rotation. In this way, the clamping device or the workpiece clamped therein can be rotated, as a result of which loosened molding sand can fall out downwards.

It is also particularly advantageous if the at least one hydraulic hammer is additionally mounted so as to be rotatable about this horizontal axis of rotation. In this way, the workpiece can also be machined by the at least one hydraulic hammer during the turning process, as a result of which the coring process is improved or accelerated.

In addition, it is particularly advantageous if the vibrating device is additionally mounted so as to be rotatable about this horizontal axis of rotation. In this way, the workpiece can also be shaken during the turning process, as a result of which the coring process is further improved or accelerated.

As part of the invention, the workpiece is rotated, vibrated and machined with the at least one hydraulic hammer in a single clamping (ie without changing the clamping device or in a single clamping device). The turning, shaking and processing of the at least one hydraulic hammer can be carried out in separate processing steps one after the other. It is part of the invention when the turning, shaking and machining with the at least one hydraulic hammer also takes place at the same time, at least in a partial phase of the machining process. In this way, the machining of the workpiece can be completed particularly quickly.

• Brechen des Gusskerns,
• Entkernen/Entsanden des Werkstücks,
• Entfernen dem Werkstück anhaftender Teile des Gusskerns und
• Entfernen eines Angusses vom Werkstück

in unterschiedlichen zeitlichen Phasen erfolgen, die einander um maximal 20% überschneiden.It is also advantageous if at least two of the processing types

• Breaking the casting core,
• Coring / desanding of the workpiece,
• Removal of parts of the casting core adhering to the workpiece and
• Removing a sprue from the workpiece

take place in different temporal phases that overlap each other by a maximum of 20%.

By executing the types of processing in essentially separate steps, the processing of the workpiece can take place in a particularly differentiated manner, for example by varying the type of impact or its position. For example, the impact energy for removing cast core parts adhering to the workpiece can be increased compared to breaking the cast core. The sprue can be removed, for example, by the hydraulic hammer striking it in a targeted manner or by causing the sprue to vibrate, and so on. The order specified for the processing types is favorable, but can also be changed. For example, the removal of a sprue from the workpiece can take place before the removal of cast core parts adhering to the workpiece. The different time phases for the different types of processing are essentially separate from one another, but can overlap by up to 20%. In other words, a phase or type of processing is at least 80% complete before the next begins. This means that, for example, at least 80% of the molding sand is removed from the workpiece or that 80% of the time has passed that is necessary for the complete removal of the molding sand before the sprue is removed, and so on.

For the above-mentioned machining of the workpiece in separate steps and in different time phases, it is also beneficial if three of the specified types of machining or all four of the specified types of machining are carried out in separate steps and in different time phases that overlap each other by a maximum of 20%.

• das Werkstück für die einzelnen Bearbeitungsarten zu unterschiedlichen Bearbeitungspositionen und über unterschiedliche Behälter bewegt wird oder
• das Werkstück an einer Bearbeitungsposition verbleibt und für die einzelnen Bearbeitungsarten unterschiedliche Behälter unter dem Werkstück positioniert werden oder
• für die einzelnen Bearbeitungsarten eine Leiteinrichtung (z.B. eine Rutsche oder ein Rohr) verstellt wird und das vom Werkstück entfernte Material in unterschiedliche Behälter eingebracht wird.

For machining the workpiece in separate steps and in different time phases, it is also advantageous if

• the workpiece is moved to different machining positions and over different containers for the individual machining types or
• the workpiece remains in a processing position and different containers are positioned under the workpiece for the individual processing types or
• a guide device (e.g. a chute or a pipe) is adjusted for the individual processing types and the material removed from the workpiece is placed in different containers.

In this way, the different, removed materials can be separated particularly well by placing them in different containers. For example, molding sand from the casting core can be introduced into a first container, sizing or sand penetration into a second container, and sprues can be introduced into a third container. This considerably simplifies the further processing of the materials.

• Brechen des Gusskerns,
• Entkernen/Entsanden des Werkstücks,
• Entfernen dem Werkstück anhaftender Teile des Gusskerns und
• Entfernen eines Angusses vom Werkstück

in einer einzigen Aufspannung des Werkstücks und/oder in einer einzigen Vorrichtung zur Bearbeitung des Werkstücks erfolgen.It is also beneficial for machining the workpiece in separate steps and in different time phases if at least two of the machining types

• Breaking the casting core,
• Coring / desanding of the workpiece,
• Removal of parts of the casting core adhering to the workpiece and
• Removing a sprue from the workpiece

take place in a single clamping of the workpiece and / or in a single device for machining the workpiece.

For example, the coring / desanding of the workpiece and the removal of cast core parts adhering to the workpiece can be carried out in one clamping of the workpiece (i.e. without changing the clamping device or in a single clamping device) and in the same device for machining the workpiece. In this way, processing is particularly fast. In principle, however, it would also be conceivable to carry out the different types of machining in one clamping of the workpiece, but in different devices for machining the workpiece. It would also be conceivable to use the different types of machining in the same device for machining the workpiece to perform, but to re-clamp the workpiece (i.e. to change the clamping device). The machining of the workpiece can then be carried out in a more differentiated manner.

It is also beneficial for machining the workpiece in one clamping of the workpiece and / or in a device for machining the workpiece if three of the specified types of machining or all four of the specified machining types in one clamping of the workpiece and / or in a device for machining the Workpiece.

• Brechen des Gusskerns,
• Entkernen/Entsanden des Werkstücks,
• Entfernen dem Werkstück anhaftender Teile des Gusskerns und
• Entfernen eines Angusses vom Werkstück

in einer einzigen Aufspannung des Werkstücks und in zeitlichen Phasen erfolgen, die einander um mindestens 80% überschneiden.But it is also advantageous if at least two of the processing types

• Breaking the casting core,
• Coring / desanding of the workpiece,
• Removal of parts of the casting core adhering to the workpiece and
• Removing a sprue from the workpiece

take place in a single clamping of the workpiece and in time phases that overlap each other by at least 80%.

Due to the quasi-simultaneous execution of the processing types, the processing of the workpiece is particularly fast. This applies in particular if three of the specified types of processing or all four of the specified types of processing take place in one clamping of the workpiece and in the phases that overlap each other. The different time phases for the different types of processing take place essentially simultaneously, but overlap each other by at least 80%. In other words, a phase or type of processing is at least 20% complete before the next begins. This means that, for example, at least 20% of the molding sand is removed from the workpiece or that 20% of the time has elapsed that is necessary for the complete removal of the molding sand before the sprue is removed, and so on. Because of the required simultaneity, it is also of particular advantage if at least two of the processing types, three of the specified processing types or all four of the specified processing types are carried out in the same device for processing the workpiece.

• Brechen des Gusskerns,
• Entkernen/Entsanden des Werkstücks,
• Entfernen dem Werkstück anhaftender Teile des Gusskerns und
• Entfernen eines Angusses vom Werkstück

nicht nur im Rahmen der Bearbeitung mit einem Hydraulikhammer beliebig kombiniert werden können, sondern dass die genannten Bearbeitungsarten auch in beliebiger Kombination mit dem Rütteln und/oder Drehen des Werkstücks ausgeführt werden können. Auch in diesem Zusammenhang können die Bearbeitungsarten insbesondere in unterschiedlichen zeitlichen Phasen erfolgen, die einander um maximal 20% überschneiden, oder auch in einer einzigen Aufspannung des Werkstücks und in zeitlichen Phasen, die einander um mindestens 80% überschneiden.For the sake of completeness, it should be noted that the types of processing

• Breaking the casting core,
• Coring / desanding of the workpiece,
• Removal of parts of the casting core adhering to the workpiece and
• Removing a sprue from the workpiece

not only can be combined as required within the framework of machining with a hydraulic hammer, but that the mentioned types of machining can also be carried out in any combination with jogging and / or rotating the workpiece. In this context, too, the types of processing can take place in particular in different time phases that overlap each other by a maximum of 20%, or also in a single clamping of the workpiece and in time phases that overlap each other by at least 80%.

For a better understanding of the invention, it is explained in more detail with reference to the following figures.

Fig. 1

eine Vorderansicht einer erfindungsgemäßen Vorrichtung;

Fig. 2

eine Rückansicht der Vorrichtung aus Fig. 1;

Fig. 3

eine perspektivische Ansicht der Vorrichtung aus Fig. 1;

Fig. 4

eine beispielhafte Vorrichtung, bei der die Hydraulikhämmer verschiebbar gelagert sind und gemeinsam nach oben geschwenkt werden können;

Fig. 5

eine Vorrichtung ähnlich der aus Fig. 4, jedoch mit vier Hydraulikhämmern;

Fig. 6

eine Vorrichtung mit großem vertikalen Verstellweg und Schutzhaube mit Absaugung;

Fig. 7

eine Vorrichtung mit mehreren auf einem Band angeordneten Spannvorrichtungen;

Fig. 8

eine Vorrichtung mit mehreren auf einem Rundtisch angeordneten Spannvorrichtungen und mehreren Bearbeitungsstationen;

Fig. 9

eine Vorrichtung mit einer Spannvorrichtung, die mit einer Rüttelvorrichtung gekoppelt oder Teil einer solchen ist;

Fig. 10

eine Vorrichtung ähnlich der aus Fig. 9, jedoch mit horizontal ausgerichteten Hydraulikhämmern;

Fig. 11

eine Vorrichtung mit einer Spannvorrichtung, welche um eine horizontale Drehachse gelagert ist, in Vorderansicht;

Fig. 12

die Vorrichtung aus Fig. 11 in Draufsicht;

Fig. 13

die Vorrichtung aus den Figuren 11 und 12 in Seitenansicht;

Fig. 14

eine schematische Darstellung, nach der das Werkstück für die einzelnen Bearbeitungsarten zu verschiedenen Bearbeitungspositionen und über verschiedenen Behältern positioniert wird;

Fig. 15

eine schematische Darstellung, nach der für die einzelnen Bearbeitungsarten verschiedene Behälter unter dem Werkstück positioniert werden;

Fig. 16

eine schematische Darstellung, bei der für die einzelnen Bearbeitungsarten eine Leiteinrichtung zu verschiedenen Behältern verstellt wird;

Fig. 17

eine erste Variante eines Hydraulikhammers, der zur Erzeugung einer Spannkraft ausgebildet ist und

Fig. 18

eine zweite Variante eines Hydraulikhammers, der zur Erzeugung einer Spannkraft ausgebildet ist.

They each show in a greatly simplified, schematic representation:

Fig. 1

a front view of a device according to the invention;

Fig. 2

a rear view of the device Fig. 1 ;

Fig. 3

a perspective view of the device Fig. 1 ;

Fig. 4

an exemplary device in which the hydraulic hammers are slidably mounted and can be pivoted upwards together;

Fig. 5

a device similar to that from Fig. 4 , but with four hydraulic hammers;

Fig. 6

a device with a large vertical adjustment path and protective hood with suction;

Fig. 7

a device with a plurality of tensioning devices arranged on a belt;

Fig. 8

a device with several clamping devices arranged on a rotary table and several processing stations;

Fig. 9

a device with a clamping device which is coupled to a vibrating device or is part of such;

Fig. 10

a device similar to that from Fig. 9 , but with horizontally aligned hydraulic hammers;

Fig. 11

a device with a clamping device, which is mounted about a horizontal axis of rotation, in a front view;

Fig. 12

the device off Fig. 11 in plan view;

Fig. 13

the device from the Figures 11 and 12th in side view;

Fig. 14

a schematic representation, according to which the workpiece is positioned for the individual processing types at different processing positions and above different containers;

Fig. 15

a schematic representation according to which different containers are positioned under the workpiece for the individual processing types;

Fig. 16

a schematic representation in which a guide device is adjusted to different containers for the individual processing types;

Fig. 17

a first variant of a hydraulic hammer which is designed to generate a clamping force and

Fig. 18

a second variant of a hydraulic hammer, which is designed to generate a clamping force.

As an introduction, it should be noted that in the differently described embodiments, the same parts are provided with the same reference numbers or the same component names (possibly with different indices), the disclosures contained in the entire description being transferred accordingly to the same parts with the same reference numbers or the same component names can. The position details chosen in the description, such as above, below, to the side, etc., also relate to the figure immediately described and shown and should be transferred accordingly to the new position in the event of a change in position.

According to the Figures 1 to 3 has a device 1 a for destroying a casting core or a hydraulic hammer 2 for removing the core from a cast workpiece. The hydraulic hammer 2 has a chisel 3 at its lower end.

On its side facing away from the chisel 3, the hydraulic hammer 2 is connected in a manner known per se with a pressure line (not shown here) and a return line with a hydraulic system also known per se, in order to transfer energy to the chisel 3 by means of hydraulic oil.

With regard to the destruction of a cast core of a workpiece or the removal of parts of the cast core adhering to the workpiece, it has been found to be particularly advantageous that the hydraulic hammer 2 with an impact frequency between 750 and 2700 impacts per minute and / or an operating pressure between 100 and 150 bar and / or a hydraulic oil flow between 12 - 35 1 / min. The machining of a workpiece works particularly well in these areas.

As from the Figures 1 to 3 It can also be seen that the device 1 a can have a support frame 4 on which the hydraulic hammer 2 is arranged. Here, the hydraulic hammer 2 can be fastened to a holding device 6 arranged on a base frame 5 of the support frame 4. As shown by way of example, the holding device 6 can comprise a back plate, a cover plate and side panels.

Furthermore, the holding device 6 can be mounted displaceably along a guide rail 7 connected to the base frame 5. A longitudinal extension of the guide rail 7 can, as shown, run vertically to an installation plane of the support frame 4. To move the holding device 6 or the hydraulic hammer 2 connected to it along the guide rail 7, the holding device 6 can be connected to an actuator 8 arranged on the base frame 5.

As from the Figures 1 to 3 As can be seen, the actuator 8 can be designed as a piston / cylinder unit, in particular as a hydraulic cylinder. A piston 9 of the piston / cylinder unit can be fastened to the holding device 6 and a cylinder 10 to the base frame 5. The reverse case would also be conceivable, namely that the piston 9 of the piston / cylinder unit is fastened to the base frame 5 and the cylinder 10 is fastened to the holding device 6.

In the Figures 1 to 3 Finally, a symbolically represented workpiece 11 is also shown, which rests on a machine table 12 of the device la. An optional pad 13 in the form of a plastic plate is inserted between the workpiece 11 and the machine table 12. The plastic plate 13 is used for damping, which prevents the impact energy from being conducted into the machine table 12 or, as a result, also into the device 1a.

The device 1 a can be used to destroy the casting core of the workpiece 11. Alternatively or additionally, the hydraulic hammer 2 can also be used to remove parts of the cast core adhering to the workpiece 11. This is to be understood in particular as the removal of “sizing” and / or “sand penetration”. That is, both the destruction of the casting core (which may include complete desanding / coring of the workpiece 11) and the removal of casting core parts adhering to the workpiece 11 can be carried out with the device 1 a and in one clamping of the workpiece 11. This can significantly reduce the time it takes to manufacture a cast product.

The destruction of the casting core, possibly complete coring / desanding of the workpiece 11, the removal of sizing from the workpiece 11 or the removal of sand penetration from the workpiece can be carried out in separate and sequential processing steps or, as mentioned above, simultaneously or simultaneously in one processing step. For example, the coring / desanding of the workpiece 11 in a first step and the removal of size, in a separate, second step Processing step. Destroying the casting core can also include destroying a casting mold (which has a cavity). Likewise, the coring / desanding of the workpiece 11 can also include the removal of a casting mold (which has a cavity). In addition, removed sizing or sand penetration can also originate from a casting mold (which has a cavity).

The device 1a can have several hydraulic hammers 2 as well as several carrier frames 4 in order to be able to hit the workpiece 11 to be machined from several directions and possibly out of phase.

The workpiece 11 is preferably clamped into the device 1 a with a force of at least 2 kN per hydraulic hammer 2. Due to the high clamping force and the associated compression of the workpiece 11, the vibration behavior of the workpiece 11 and also the vibration behavior of the system, including the workpiece 11 and the device 1a, are significantly changed, which has a positive effect on the destruction of the casting core or the desanding / coring process will. In general, the hydraulic hammer 2 stimulates the workpiece 11 over a broad band, not least through wave reflections on the machine frame 12 of the device 1 a.

In the in the Figures 1 to 3 In the example shown, the workpiece 11 is clamped in the device 1 a with the aid of the hydraulic cylinder 8. A clamping force is advantageously transmitted to the workpiece 11 exclusively with the hydraulic hammer 2, which also destroys the cast core or removes adhering cast core parts from the workpiece 11. That is, the device 1a in this case has the only contact element for pressing the workpiece 11 against the machine table 12, the hydraulic hammer 2, which is also set up to destroy the cast core or to remove adhering cast core parts. The clamping force is preferably transmitted to the workpiece 11 by the hydraulic hammer 2 during the entire machining process.

But this is not the only conceivable possibility. Rather, it is also conceivable that the device 1a has separate clamping devices. It is also conceivable that the hydraulic cylinder 8 is omitted and the clamping movement itself takes place with the hydraulic hammer 2, which also destroys the cast core or removes adhering cast core parts from the workpiece 11 (see also FIG Figures 17 and 18 ).

In general, it is advantageous if the blow performed by the hydraulic hammer 2 does not take place on the molding sand of the casting core, but on the (usually metallic) workpiece 11. The impact is therefore particularly hard or energy-intensive. In this case, the chisel 3 advantageously has no point, but is flattened.

In an exemplary example, it should now be made clear that the destruction of a cast core or the coring / desanding with the aid of a hydraulic hammer 2 is significantly more efficient than with conventional pneumatic hammers. A coring / desanding process with four pneumatic hammers is used as an example, which cores / desandes workpieces 11 in 10 seconds with a cycle time of 50 seconds. This process requires around 4.8 m ³ / min of air compressed to a pressure of 6 bar. The electrical power required for the compressor in this case is around 29.0 kW.

Only two hydraulic hammers 2 are required for the same core removal / desanding service, which core / desand the workpieces 11 in 5 seconds with a cycle time of 50 seconds. A volume flow of around 20 1 / min hydraulic oil at a pressure of 150 bar is required for this process. The electrical power required for the hydraulic unit in this case is around 5.1 kW. This means that the coring / desanding with a hydraulic system surprisingly only requires around 18% of the average electrical power that is required for the same ginning / desanding with a pneumatic system.

Fig. 4 now shows an exemplary device 1b with several hydraulic hammers 2a, 2b. The hydraulic hammers 2a, 2b are mounted displaceably on a plurality of guides (in particular guide rails) 7x, 7y, 7z connected opposite to the support frame 4. Specifically, a longitudinal extension of a first guide rail 7x runs horizontally or parallel to a set-up plane of the support frame 4, a longitudinal extension of a second guide rail 7y runs horizontally or parallel to a set-up plane of the support frame 4 and at right angles to the first guide rail 7x, and a longitudinal extension a third guide 7z runs vertically to an installation plane of the support frame 4. The hydraulic hammers 2a, 2b can thus be adjusted in all spatial directions. In this example, the setting is made manually, but it can also be done using actuators 8.

A clamping device 14 for a workpiece 11 (not shown) is arranged in the active area of the hydraulic hammers 2a, 2b, so that the workpiece 11 is held in place during the core removal process.

The hydraulic hammers 2a, 2b can in this example between a working position in which a workpiece 11 clamped in the clamping device 14 is located in the effective area of the hydraulic hammers 2a, 2b, and a rest position in which a workpiece 11 clamped in the clamping device 14 is outside the Effective range of the hydraulic hammers 2a, 2b is moved. Specifically, the hydraulic hammers 2a, 2b can be pivoted into the rest position or the working position with the aid of the crank drive 15. In the Fig. 4 the working position of the hydraulic hammers 2a, 2b is shown.

Fig. 5 shows a further device 1c for destroying a casting core / removing casting core parts adhering to the workpiece 11, which is the same as in FIG Fig. 4 shown device 1b is very similar in terms of structure and operation. In contrast to the device 1b, the device 1c has four hydraulic hammers 2a..2d.

Fig. 6 shows a further device 1d for destroying a casting core / removing casting core parts adhering to the workpiece 11, which are removed from the in the Figures 4 and 5 shown devices lb, 1c differs. On the one hand, the vertical adjustment takes place via two round columns functioning as linear guides 7z; on the other hand, the device 1d has a protective hood 16 with a suction line 17.

Fig. 7 shows a device 1e in which a plurality of tensioning devices 14 are arranged on a belt 18. It would also be conceivable for a chain to be provided instead of the belt 18. With the aid of the belt 18, a tensioning device 14 can be moved into the active area of the hydraulic hammers 2a, 2b. In this way, particularly efficient machining of workpieces 11 is possible.

It would also be conceivable that several processing stations with different hydraulic hammers 2a, 2b are provided in the course of the belt 18. In this case, the clamping device 14 can be moved to a first position with a workpiece 11, which is machined there with at least one first hydraulic hammer 2a, 2b. Then the clamping device 14 with the workpiece 11 is moved to a second position, which is machined there with at least one second hydraulic hammer.

Fig. 8 shows a device 1f with several such processing stations 19a..19c, and with a rotary table 20 instead of a belt 18. Specifically, the processing station 19a comprises the hydraulic hammers 2a, 2b, the processing station 19b three more hydraulic hammers and the processing station 19c two more hydraulic hammers. With the aid of the rotary table 20, a clamping device 14 can be moved (rotated) into the active area of the processing stations 19a..19c or their hydraulic hammers 2a, 2b. Thus, the clamping device 14 can be moved to a first position P1 in the effective area of the first processing station 19a or the first hydraulic hammers 2a, 2b, where the workpiece 11 (not shown) clamped in the clamping device 14 is processed with the first hydraulic hammers 2a, 2b. In a further work step, the clamping device 14 is moved to a second position P2 in the active area of the second machining stations 19b or the second hydraulic hammers, where the workpiece 11 clamped in the clamping device 14 is machined with the second hydraulic hammers. In yet another work step, the clamping device 14 is moved to a third position P3 in the effective area of the third machining station 19c or the third hydraulic hammers, where the workpiece 11 clamped in the clamping device 14 is machined with the third hydraulic hammers. Finally, the clamping device 14 is rotated to a fourth position P4, at which the finished workpiece 11 can be removed and a new one to be machined can be clamped. For the sake of completeness, it is noted that, of course, not just one workpiece 11 can be located in the device 1f, but all of the clamping devices 14 can be occupied by workpieces 11. Accordingly, the device 1f is then fed quasi continuously.

In a very similar manner, in the course of the band 18 the in Fig. 7 device 1e shown several processing stations 19a..19c can be provided.

In general, the hydraulic hammers 2a..2d shown in the figures can be operated in a synchronized or unsynchronized manner. In the first case, in particular, a control is provided which is set up to control a plurality of hydraulic hammers 2a..2d in a synchronized manner.

It is also conceivable that the belt 18 or the rotary table 20 moves discontinuously and stops at a position P1..P4 where the workpiece 11 is processed. However, it would also be conceivable that the belt 18 or the rotary table 20 moves continuously and the processing stations 19a .. 19c are moved uniformly with the clamping device 14 on the belt 18 or the rotary table 20 while the workpiece 11 is being machined. After machining, the machining station 19a..19c retracts, and the cycle begins again.

For this purpose, one of the guides 7x, 7y, 7z can be aligned in the direction of movement of the belt 18, so that the mentioned movement of the processing station 19a..19c is possible. In the case of the device 1f, the processing stations 19a..19c can be rotatably mounted about the vertical axis z (for example, arranged on a support rotatably mounted about the vertical axis z) so that the uniform movement of the processing stations 19a..19c and the clamping devices 14 is made possible . Of course, it would also be possible to mount the processing stations 19a .. 19c on two (longer) horizontal guide rails 7x, 7y, and to execute a circular path with the aid of superimposed movements.

Fig. 9 shows a further device 1g, which in the Figures 4 and 5 shown devices 1b and 1c is similar in terms of structure and function. In contrast to this, the clamping device 14 in this example is coupled to a vibrating device or is arranged on it. In the Fig. 9 the vibrating motor 21 of the vibrating device is specifically designated. During the shaking process, the hydraulic hammers 2 a.

Fig. 10 shows a device 1h, which is the in Fig. 9 device 1g shown is similar in terms of structure and function. Here, too, the clamping device 14 is coupled to a vibrating device or is arranged on it (see the vibrating motor 21). The hydraulic hammers 2a..2d are aligned horizontally in this example.

the Figures 11 to 13 show a further alternative design of a device 1i. Specifically shows the Fig. 11 the device 1i in front view, the Fig. 12 in plan view and the Fig. 13 in side view. In contrast to the designs shown so far, the device 1i has a clamping device 14 which is mounted rotatably about a horizontal axis of rotation D. In this way, the workpiece 24 can be rotated, as a result of which loosened molding sand can fall out downwards.

Optionally, the hydraulic hammers 2a..2c can also be rotatably mounted about this horizontal axis of rotation D, as is the case with the device 1i. In this way, the core removal process can also be continued while the workpiece 24 is rotating. In addition, it is also conceivable that a vibrating device is coupled to the clamping device 14 or arranged on it. This vibrating device can also be mounted rotatably about this horizontal axis of rotation D, so that the workpiece 24 can also be vibrated during the turning process.

Accordingly, the workpiece 11, 24 can be rotated, jolted and machined with the at least one hydraulic hammer 2, 2a..2d in a single clamping. It is particularly advantageous if the workpiece 11, 24 is rotated, jolted and machined with the at least one hydraulic hammer 2, 2a..2d at the same time. In this way, the machining of the workpiece 11, 24 can be completed particularly quickly.

In the case of the device 1i, the loading takes place via the conveyor track 23, via which the workpieces 24 can be introduced into the protective hood 16 in which the workpiece 24 is machined.

• Brechen des Gusskerns,
• Entkernen/Entsanden des Werkstücks 11, 24,
• Entfernen dem Werkstück 11, 24 anhaftender Teile des Gusskerns und
• Entfernen eines Angusses vom Werkstück 11, 24

in unterschiedlichen zeitlichen Phasen, die einander um maximal 20% überschneiden.In a further, particularly advantageous embodiment, at least two of the processing types take place

• Breaking the casting core,
• Coring / desanding of the workpiece 11, 24,
• Removing the workpiece 11, 24 adhering parts of the casting core and
• Removing a sprue from the workpiece 11, 24

in different time phases that overlap each other by a maximum of 20%.

By executing the types of processing in essentially separate steps, the processing of the workpiece 11, 24 can take place in a particularly differentiated manner, for example by varying the type of impact or its position. For example, the impact energy for removing casting core parts adhering to the workpiece 11, 24 can be increased compared to breaking the casting core. The sprue can be removed, for example, by the hydraulic hammer 2, 2a..2d executing a targeted blow on it or causing the sprue to vibrate, and so on.

The workpiece 11, 24 can be moved to different machining positions P1..P4 for the individual machining types. For example, the workpiece 11, 24 at the first machining position P1 of the Fig. 8 The device 11 shown are cored / desanded, are freed from adhering cast core parts at the second processing position P2 and are separated from a sprue at the third processing position P3. At the processing stations 19a..19c, strokes of different types can be carried out, as indicated in the previous paragraph.

Equivalently, the workpiece 11, 24 could also remain at a machining position P1..P3 when the machining stations 19a..19c are moved to the machining positions P1..P3.

Of course, the principle presented is not tied to a rotary movement, but can also be based on a translational movement. In particular, the principle presented can be applied to the Fig. 7 Device shown le can be applied.

The order specified for the processing types is favorable, but can also be changed. For example, a sprue can be removed from the workpiece 11, 24 before parts of the casting core adhering to the workpiece 11, 24 are removed.

The different time phases for the different types of processing are essentially separate from one another, but can overlap by up to 20%. In other words, a phase or type of processing is at least 80% complete before the next begins. This means that, for example, at least 80% of the molding sand is removed from the workpiece 11, 24 or that 80% of the time has elapsed that is necessary for the complete removal of the molding sand before the sprue is removed, and so on.

For the above-mentioned machining of the workpiece 11, 24 in separate steps and in different time phases, it is also favorable if three of the specified machining types or all four of the specified machining types take place in separate steps and in different temporal phases, which are mutually exclusive by a maximum of 20%. overlap.

Due to the temporal separation of the types of processing, the different, removed materials can be separated particularly well, for example by placing them in different containers. For example, molding sand from the casting core can be introduced into a first container, sizing or sand penetration into a second container, and sprues can be introduced into a third container. This considerably simplifies the further processing of the materials.

It is advantageous if the workpiece 11, 24 is moved to different machining positions P1..P3 and over different containers 25a..25c for the individual machining types, as is the case in FIG Fig. 14 is shown schematically and indicated with arrows. If the workpiece 11, 24 is moved to the first machining position P1, then it is machined there by the first hydraulic hammer 2a, and the material removed from the workpiece 11, 24 falls into the first container 25a. If the workpiece 11, 24 is moved to the second machining position P2, then it is machined there by the second hydraulic hammer 2b, and the material removed from the workpiece 11, 24 falls into the second container 25b. If the workpiece 11, 24 is finally moved to the third machining position P3, then it is machined there by the third hydraulic hammer 2c, and the material removed from the workpiece 11, 24 falls into the third container 25c. In the Fig. 14 individual hydraulic hammers 2a..2c are shown, of course the principle presented can also be applied to several processing stations 19a..19c. More or less than three processing positions P1..P3, more or less than three hydraulic hammers 2a..2c and more or less than three containers 25a..25c can also be provided.

A specific device 1f for implementing this variant embodiment is, for example, in FIG Fig. 8 shown. Separate containers 25a..25c can be arranged there at the processing positions P1..P3. As mentioned, the workpiece 11, 24 can be cored / desanded at the first machining position P1, freed from adhering parts of the casting core at the second machining position P2 and separated from a sprue at the third machining position P3. The different materials removed from the workpiece 11, 24 then fall into different containers 25a..25c and can easily be further processed.

That in the Fig. 14 The method shown is not tied to a rotary movement, but can also be based on a translational movement. In particular, the principle presented can therefore be applied to the Fig. 7 Device shown le can be applied.

Equivalent to the in Fig. 14 visualized procedure, it is conceivable that the workpiece 11, 24 remains at a processing position P1..P3 and different containers 25a..25c are positioned under the workpiece 11, 24 for the individual types of processing, as in FIG Fig. 15 is shown schematically and indicated with arrows. In this way, too, the mentioned separation of the materials removed from the workpiece 11, 24 can take place, and this principle is also based on the in Fig. 8 shown device 1f transferable.

Finally, it is equally conceivable that a guide device 26 (eg a chute) is adjusted for the individual processing types and the material removed from the workpiece 11, 24 is introduced into different containers 25a..25c, as in FIG Fig. 16 is shown schematically. In the Fig. 16 the guide device 26 is specifically set to the third container 25c, but it can of course also be set to the containers 25a, 25b. Of course, this is not the only thing in Fig. 14 visualized procedures on the in Fig. 7 device shown le and in Fig. 8 shown device 1f applicable, but also in the Figures 15 and 16 shown design variants

• Brechen des Gusskerns,
• Entkernen/Entsanden des Werkstücks 11, 24,
• Entfernen dem Werkstück 11, 24 anhaftender Teile des Gusskerns und
• Entfernen eines Angusses vom Werkstück 11, 24

in einer einzigen Aufspannung des Werkstücks 11, 24 und/oder in einer einzigen Vorrichtung 1a..1i zur Bearbeitung des Werkstücks 11, 24 erfolgen.It is still favorable if at least two of the processing types

• Breaking the casting core,
• Coring / desanding of the workpiece 11, 24,
• Removing the workpiece 11, 24 adhering parts of the casting core and
• Removing a sprue from the workpiece 11, 24

take place in a single clamping of the workpiece 11, 24 and / or in a single device 1a..1i for machining the workpiece 11, 24.

Accordingly, the workpiece 11, 24 remains in one and the same clamping device 14 for at least two processing types, and / or the workpiece 11, 24 is processed in at least two processing types in one and the same device 1a..1i. In this way, processing is particularly fast. For those in the Fig. 7 device shown le and the Fig. 8 The device 1f shown means that the workpiece 11, 24 remains clamped in the clamping device 14 and is only moved to a different machining position P1..P4. Alternatively, the processing stations 19a..19c can again be moved to the processing positions P1..P3.

In principle, however, it would also be conceivable to carry out the different types of machining in one clamping of the workpiece 11, 24, but in different devices 1a... 1i for machining the workpiece 11, 24. For example, several devices 1a..1i can be connected via a conveyor belt. The limit to that in the Fig. 7 illustrated device le is fluid.

It would also be conceivable to carry out the different types of machining in the same device 1 a. For example, the one in the Fig. 8 The device 1f shown may be designed so that the rotary table 20 cannot be rotated. In this case, a workpiece 11, 24 would be clamped in different clamping devices 14 of the device 1f for the different types of machining. Here, too, the boundary between different devices 1a..1i is fluid.

It is favorable for the machining of the workpiece 11, 24 in one clamping of the workpiece 11, 24 and / or in a device 1a..1i for machining the workpiece 11, 24 if three of the specified machining types or all four of the specified machining types in clamping of the workpiece 11, 24 and / or in a device 1a..1i for machining the workpiece 11, 24.

• Brechen des Gusskerns,
• Entkernen/Entsanden des Werkstücks 11, 24,
• Entfernen dem Werkstück 11, 24 anhaftender Teile des Gusskerns und
• Entfernen eines Angusses vom Werkstück 11, 24

in einer einzigen Aufspannung des Werkstücks 11, 24 und in zeitlichen Phasen erfolgen, die einander um mindestens 80% überschneiden.It is also advantageous if at least two of the processing types

• Breaking the casting core,
• Coring / desanding of the workpiece 11, 24,
• Removing the workpiece 11, 24 adhering parts of the casting core and
• Removing a sprue from the workpiece 11, 24

take place in a single clamping of the workpiece 11, 24 and in time phases that overlap each other by at least 80%.

Due to the quasi-simultaneous execution of the types of machining, the machining of the workpiece 11, 24 takes place particularly quickly. This applies in particular if three of the specified types of processing or all four of the specified types of processing take place in one clamping of the workpiece 11, 24 and in the phases that overlap each other.

For example, editing in the in Fig. 4 shown device 1b take place. The provision of several processing stations 19a .. 19c is not necessary. Rather, the blows are advantageously carried out in a manner which produce the or all of the desired effects. The control of the hydraulic hammers 2, 2a..2d is then particularly simple.

The different time phases for the different types of processing take place essentially simultaneously, but overlap each other by at least 80%. In other words, a phase or type of processing is at least 20% complete before the next begins. This means that, for example, at least 20% of the molding sand is removed from the workpiece 11, 24 or that 20% of the time has elapsed that is necessary for the complete removal of the molding sand before the sprue is removed, and so on. Because of the simultaneity required, it is also special Advantage if at least two of the processing types, three of the specified processing types or all four of the specified processing types are carried out in the same device 1a..1i for processing the workpiece 11, 24.

Fig. 17 now shows a special type of hydraulic hammer 2e. The hydraulic hammer 2e comprises an inner cylinder 27 in which a hammer 28 is movably mounted. A front bearing piece 29, in which a first bush 30 is mounted, is attached to the inner cylinder 27. A second bush 31 is located in the inner cylinder 27. The flat chisel 3 is slidably mounted in the two bushes 30 and 31. Furthermore, the hydraulic hammer 2e comprises an outer cylinder 32 in which the inner cylinder 27 is slidably mounted. A pressure tube 33, which is guided through a third bushing 34 through the outer cylinder 32, is fastened to the inner cylinder 27. Finally, a pressure connection 35 is arranged in the outer cylinder 32.

The function of the hydraulic hammer 2e is now as follows:
If hydraulic oil is fed into the outer cylinder 32 via the pressure connection 35, the inner cylinder 27 is pushed out of the outer cylinder 32 and into the Fig. 17 moved to the right. If hydraulic oil is diverted from the outer cylinder 32 via the pressure connection 35, the inner cylinder 27 is moved into the outer cylinder 32 and into the Fig. 17 shifted to the left. In the example shown, the inner cylinder 27 is moved into the outer cylinder 32 when the outer cylinder 32 is evacuated. It is of course also conceivable that the inner cylinder 27 is moved into the outer cylinder 32 by a spring force and the hydraulic oil accordingly flows off automatically.

If hydraulic oil is fed into the inner cylinder 27 via the pressure pipe 33, the hammer 28 is directed towards the chisel 3 and in the Fig. 17 accelerated to the right and ultimately struck against the chisel 3. If hydraulic oil is diverted from the inner cylinder 27, the hammer 28 is away from the chisel 3 and in the Fig. 17 moved to the left. In the space between the hammer 28 and the chisel 3 there can be air which is compressed or is passed to the outside through a bore (not shown). If the air is compressed in the space mentioned, the hammer 28 is by the as Air spring acting, compressed air reset. However, it is also conceivable that the return of the striking piece 28 is brought about or at least supported by a mechanical spring. It is also conceivable that there is hydraulic oil in the space between the hammer 28 and the chisel 3. This can be fed back into an oil container via a bore (not shown). Furthermore, the striking piece 28 can also be reset in this case in that the space between the striking piece 28 and the chisel 3 is acted upon with pressurized oil.

The chisel 3 can advantageously be pressed against a workpiece 11, 24 by applying pressure to the outer cylinder 32. By applying pressure to the inner cylinder 27, an impact can be superimposed on this clamping force, which is introduced into the workpiece 11, 24 and there triggers the effects already described. In other words, only the hydraulic hammer 2e is required to generate a clamping force acting on the workpiece 11, 24. That is, the hydraulic hammer 2e not only functions as the only contact element for pressing the workpiece 11, 24 against the machine table 12, but it also generates the clamping force. A separate hydraulic cylinder 8 for generating the clamping force can then be omitted.

In Fig. 18 an alternative variant of a hydraulic hammer 2f is shown, which is similar to that shown in FIG Fig. 17 hydraulic hammer 2f shown is very similar. In contrast to this, the pressure pipe 33 is omitted and a first controllable valve 36 is arranged on the rear side of the inner cylinder 27, with which the inner cylinder 27 can be connected to the outer cylinder 32 or separated from it. In this way, when pressurized oil, the hammer 28 can be accelerated towards the chisel 3 and struck against it. In addition to the first valve 36, the space behind the hammer 28 is also connected to a return line 37, in the course of which a second controllable valve 38 is arranged. For a return movement of the hammer 28, the hydraulic oil can be diverted via this return line 37 from the space behind the hammer 28. The valves 36 and 38 are accordingly activated alternately.

At this point it should be noted that the designs shown in the figures are not restricted to the use of a hydraulic hammer 2a..2f. Rather, in the shown Figures 1a..1i In principle, pneumatic hammers or electric hammers can also be used.

For the sake of clarity, it should finally be pointed out that, for a better understanding of the structure, some elements can be shown not to scale and / or enlarged and / or reduced. <b> List of reference symbols </b> 1a..1i (Coring) device 26th Guide device (slide) 2, 2a..2f Hydraulic hammer 27 inner cylinder 3 chisel 28 Impact piece 4th Support frame 29 front bearing piece 5 Base frame 30th first socket 6th Holding device 31 second socket 7, 7x..7z Guide / guide rail 32 outer cylinder 8th Actuator 33 Pressure pipe 9 Pistons 34 third socket 10 cylinder 35 Pressure connection 11 workpiece 36 first valve 12th Machine table 37 Return line 13th (Plastic) pad 38 second valve 14th Jig 15th Crank drive / swivel drive P1..P4 Machining position z vertical axis 16 Protective hood 17th Suction 18th Ribbon / chain 19a..19c Processing station 20th Round table 21 Vibrating motor 22nd Rotary motor 23 Conveyor track 24 workpiece 25a..25c container

Claims (14)

1. A device (1a..1i) for destroying a casting core of a cast workpiece (11, 24) and/or for removing parts of a casting core adhering to the workpiece (11, 24), wherein the device (1a..1i) comprises at least one hammer, wherein the at least one hammer is a hydraulic hammer (2, 2a..2f), wherein a clamping device (14) for a workpiece (11, 24) is formed, said clamping device (14) being arranged in the effective region of the at least one hydraulic hammer (2, 2a..2f) or being movable there, characterized in that the clamping device (14) is coupled to a vibrator device (21) or is arranged thereon, and that the clamping device (14) is mounted so as to be rotatable about a horizontal axis of rotation (D), wherein the device (1a..1i) is designed such that the workpiece (11, 24) can be simultaneously rotated, caused to vibrate and processed using the at least one hydraulic hammer (2, 2a..2f).
2. The device (1a..1i) according to claim 1, characterized in that it comprises at least one carrier frame (4) on which the hydraulic hammer (2, 2a..2f) is arranged.
3. The device (1a..1i) according to claim 2, characterized in that the hydraulic hammer (2, 2a..2f) is mounted on a holding device (6) arranged on a base frame (5) of the carrier frame (4).
4. The device (1a..1i) according to claim 3, characterized in that the holding device (6) is mounted so as to be displaceable at least on a guide (7, 7x..7z) connected to the base frame (5).
5. The device (1a..1i) according to claim 4, characterized in that a longitudinal extension of a first guide (7x) runs horizontally and/or parallel to an installation plane of the carrier frame (4) and/or that a longitudinal extension of a second guide (7y) runs horizontally and/or parallel to an installation plane of the carrier frame (4) as well as at right angles to the first guide (7x) and/or a longitudinal extension of a third guide (7z) runs vertically to an installation plane of the carrier frame (4).
6. The device (1a..1i) according to claim 5, characterized in that the holding device (6) connected to at least one actuator (8) arranged on the base frame (5).
7. The device (1a..1i) according to claim 6, characterized in that the at least one actuator (8) is designed as a piston/cylinder unit, in particular as a hydraulic cylinder.
8. The device (1a..1i) according to claim 7, characterized in that a piston (9) of the piston/cylinder unit is mounted on the holding device (6) and a cylinder (10) is mounted on the base frame (5).
9. A method for destroying a casting core of a cast workpiece (11, 24), wherein at least one hydraulic hammer (2, 2a..2f) is used for destroying the casting core, wherein a clamping device (14) for a workpiece (11, 24) is formed, said clamping device (14) being arranged in the effective region of the at least one hydraulic hammer (2, 2a..2f) or being movable there, characterized in that the clamping device (14) is coupled to a vibrator device (21) or is arranged thereon, and that the clamping device (14) is mounted so as to be rotatable about a horizontal axis of rotation (D), wherein the workpiece (11, 24) can be simultaneously rotated, caused to vibrate and processed using the at least one hydraulic hammer (2, 2a..2f).
10. The method according to claim 9, characterized in that the clamping device (14) for the workpiece (11, 24) is caused to vibrate.
11. The method according to one of claims 9 to 10, characterized in that the clamping device (14) for the workpiece (11, 24) is rotated about a horizontal axis of rotation (D).
12. The method according to claims 9 to 11, characterized in that the workpiece (11, 24) is rotated, caused to vibrate and processed using the at least one hydraulic hammer (2, 2a..2f) in a single clamping.
13. The method according to one of claims 9 to 12, characterized in that the clamping device (14) with a workpiece (11, 24) is moved to a first position (PI), there the workpiece (11, 24) is processed using at least one first hydraulic hammer (2, 2a..2f), then the clamping device (14) with the workpiece (11, 24) is moved to a second position (P2) and there the workpiece (11, 24) is processed using at least one second hydraulic hammer (2, 2a..2f).
14. The method according to one of claims 9 to 13, characterized in that multiple hydraulic hammers (2, 2a..2f) are controlled in a synchronized manner.

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