Device for shooting a foundry core

Abstract

The present invention relates to a device for shooting a foundry core which surrounds a free inner space on its outer boundaries, with the device having a mould cavity representing the foundry core, which circulates around an inner slider extending along a longitudinal axis and is delimited on its outer side by an outer slider circulating around the mould cavity, with the clear width of the mould cavity being determined by the distance of the inner surface of the outer slider, assigned to the mould cavity, to the outer surface of the inner slider. The device according to the invention allows for operationally-safe manufacture of foundry cores that are tubular in their base form, but finely-structured in their walls and also on a large scale. This is achieved by the inner slider segments being displaceable between a removal position, in which they are positioned approximated in relation to one another and to the longitudinal axis of the inner slider and the clear width of the mould cavity present between the inner slider and the outer slider is increased, into a shooting position approximating the outer slider, in which the clear width of the mould cavity corresponds to a target specification for the foundry core to be shot.

Claims

1. A device for shooting a foundry core, which surrounds a free inner space on its outer boundaries, wherein the device has a mould cavity representing the foundry core, which circulates around an inner slider extending along a longitudinal axis and is delimited on its outer side by an outer slider circulating around the mould cavity, wherein a clear width of the mould cavity is determined by a distance of an inner surface, assigned to the mould cavity, of the outer slider to an outer surface of the inner slider, wherein the inner slider is divided into at least three inner slider segments along dividing planes, which extend in a longitudinal direction of the inner slider and wherein the inner slider segments are displaceable between a removal position, in which they are positioned approximated in relation to one another and to the longitudinal axis of the inner slider and the clear width of the mould cavity present between the inner slider and the outer slider is increased, into a shooting position approximating the outer slider, in which the clear with of the mould cavity corresponds to a target specification for the foundry core to be shot, characterised in that one of the inner slider segments is movable in a radial direction on the longitudinal axis of the inner slider into a receiving portion, which is laterally delimited by in each case one further slider segment and expands in the direction of the longitudinal axis of the inner slider in the case of the slider segments being in the shooting position.

2. The device according to claim 1, characterised in that the dividing planes between the inner slider segments intersect in the longitudinal axis of the inner slider.

3. The device according to claim 2, characterised in that the dividing planes between the inner slider segments are arranged at even angular intervals distributed around the longitudinal axis of the inner slider.

4. The device according to claim 1, characterised in that at least one inner slider segment has an offset protruding in the circumferential direction, which engages into a correspondingly formed recess of the in each case adjacent inner slider segment.

5. The device according to claim 1, characterised in that the movements of the inner slider segments are coupled to one another by means of a guide.

6. The device according to claim 1, characterised in that an adjusting device is provided for adjusting the inner slider segments between their removal position and their shooting position.

7. The device according to claim 6, characterised in that the adjusting device comprises a wedge element, adjustable in the longitudinal direction of the inner slider, directed with its tip into an inner space of the inner slider surrounded by the inner slider elements, having a wedge surface, which abuts on a surface, assigned to the wedge element, of at least one of the inner slider segments.

8. The device according to claim 7, characterised in that the wedge element is formed in a mandrel shape and a wedge surface is assigned to the wedge element of each of the inner slider segments, on which wedge surface the respective assigned inner slider segment abuts.

9. The device according to claim 6, characterised in that the adjusting device comprises a control connecting rod with a connecting rod guide, with which at least one of the inner slider segments is articulatedly coupled and in that the control connecting rod is adjustable, entraining the inner slider segment, between a position corresponding to the removal position of the inner slider segment and a position corresponding to the shooting position of the inner slider segment.

10. The device according to claim 9, characterised in that a connecting rod guide is assigned to each inner slider segment in the control connecting rod, with which the inner slider segment, assigned in each case, is articulatedly coupled.

11. The device according to claim 10, characterised in that the connecting rod guides are arranged at regular angular intervals distributed around a rotary axis of the control connecting rod arranged coaxially to the longitudinal axis of the inner slider.

12. The device according to claim 1, characterised in that the outer slider is divided into at least two outer slider segments, which, for a removal of the finished foundry core, are movable from their shooting position, in which they, sitting closely together, delimit the mould cavity b on its outer side, into a removal position.

13. The device according to claim 12, characterised in that an adjusting device is provided for adjusting the outer slider segments between their removal position and their shooting position.

14. The device according to claim 13, characterised in that the adjusting device for the adjustment of the outer slider segments comprises a control connecting rod with a connecting rod guide with which at least one of the outer slider segments is articulatedly coupled and in that the control connecting rod, entraining the outer slider segment, is adjustable between a position corresponding to the removal position of the outer slider segment and a position corresponding to the shooting position of the outer slider segment.

15. The device according to claim 13, characterised in that a connecting rod guide is assigned to each outer slider segment in the control connecting rod, with which the outer slider segment, assigned in each case, is articulatedly coupled.

16. The device according to claim 1, characterised in that it comprises at least one base plate on which the outer slider and the inner slider are mounted.

17. The device according to claim 1, characterised in that it comprises an ejector device for ejecting the finished foundry core.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The invention is explained below in greater detail using a drawing representing exemplary embodiments. Its figures show in each case schematically:

(2) FIG. 1 a prior art first device for shooting a foundry core with perspective view partially cut in the shooting position.

(3) FIG. 2 the device according to FIG. 1 in a view from above;

(4) FIG. 3 the device according to FIG. 1 with inner slider and outer slider in the removal position in a view corresponding to FIG. 1;

(5) FIG. 4 the device according to FIG. 3 in a view from above;

(6) FIG. 5 the device according to FIG. 1 in a removal position in a perspective view;

(7) FIG. 6 a second device according to the invention for shooting a foundry core in the shooting position in a view from above;

(8) FIG. 7 the device according to FIG. 6 in a view from below;

(9) FIG. 8 the device according to FIG. 7 with inner slider in the removal position in the shooting position in a perspective view from above;

(10) FIG. 9 the device according to FIG. 8 in a perspective view from below;

(11) FIG. 10 an inner slider in a perspective view.

DESCRIPTION OF THE INVENTION

(12) The device 1 shown in FIGS. 1 to 4 and the device 100 shown in FIGS. 6 to 9 serve to shoot a foundry core G, as is shown by way of example in FIG. 5. The individual parts of the devices 1, 100 are made from the materials proven in the prior art for such purpose.

(13) The foundry core G to be shot made from a conventional moulding material provided as moulding sand/binder mixture therefore has the base shape of a cylindrical hollow body with a circular cross-section, which extends over a height H in the longitudinal direction LR coaxially to the central longitudinal axis LS of the foundry core G. The foundry core G thus surrounds, with its circumferential wall U, an inner space I open at its ends and represented by the inner slider 2. The circumferential wall U is in this case not formed as a solid, closed wall, but rather is broken down into radially protruding projections V, recesses A, local material accumulations M, connection webs S and the like.

(14) The device 1, 100 comprises in each case an inner slider 2, an outer slider 3 and a base plate 4. A mould cavity 5 indicated only schematic for the sake of clarity is surrounded between the outer slider 3 and the inner slider 2, said mould cavity representing the foundry core G to be shot with the device 1. In this case, the inner slide 2, with its outer circumferential surface 6, and the outer slider 3, with its inner circumferential surface 7, delimit the mould cavity 5. The distance of the inner circumferential surface 7 to the outer circumferential surface 6 determines the clear width W of the mould cavity 5.

(15) The inner slider 2 is in each case divided into five uniformly formed inner slider segments 2a to 2e which are arranged at even angular intervals around the central longitudinal axis LZ of the inner slider 2. The longitudinal axis LZ is located in each of the dividing planes T1 to T5, by way of which the inner slider segments 2a to 2e are separated from one another. The dividing planes T1 to T5 therefore intersect in the longitudinal axis LZ.

(16) The inner slider segments 2a to 2e sit on the base plate 4 and are mounted on the same.

(17) In the case of the device 1 represented in FIGS. 1 to 4, the base plate 4 has a central opening 8 aligned concentrically to the longitudinal axis LZ, proceeding from which five slotted guides 9a, 9d are formed distributed around the centre of the opening 8 at even angular intervals in a star shape.

(18) One of the inner slider segments 2a to 2e is in each case assigned to the guides 9a, 9d. In this case, a sword-like guide member 10a, 10d is fastened on the underside of the inner slider segments 2a to 2e assigned to the base plate 4, by means of which the inner slider segment 2a to 2e in question is displaceably mounted in a positive-locking manner in the guide 9a, 9d assigned in each case.

(19) The inner slider segments 2a to 2e in each case have an oblique surface 11a, 11d on their inner side assigned to the longitudinal axis LZ, which is inclined proceeding from the underside of the inner slider segments 2a to 2e assigned to the base plate 4 in the direction of the upper side 12 of the device 1 such that the distance between the oblique surfaces 11a, 11d of the inner slider segments 2a to 2e continually decreases in the direction of the upper side 12.

(20) A mandrel-shaped wedge element 13 is pushed into the opening 8 on which a wedge surface 13a, 13d is formed at regular angular intervals distributed around the longitudinal axis LZ for each of the inner slider segments 2a to 2e, which increases proceeding from the underside of the wedge element 13 assigned to the base plate 4 in the direction of the upper side 12 such that the wedge surfaces 13a, 13d, with the longitudinal axis LZ, form an acute angle. In this case, the inclination of the wedge surfaces 13a, 13d is the same as the inclination of the oblique surfaces 11a, 11d of the inner slider segments 2a to 2e such that the wedge surfaces 13a, 13d of the wedge element 13 closely abut on the oblique surfaces 11a, 11d of the inner slider segments 2a to 2e. A T-groove guide 14a to 14e, 15a to 15e is formed into the oblique surfaces 11a, 11d and the wedge surfaces 13a, 13d, which extend over the height of the respective oblique surface 11a, 11d and wedge surface 13a, 13d and are thus aligned such that a T-groove guide 15a to 15e of the wedge surfaces 13a, 13d opposes each T-groove guide 14a to 14e of the oblique surfaces 11a, 11d. A double T-shaped slide member, not shown here, is in each case mounted in the T-groove guides 14a to 14e, 15a to 15e assigned to one another in such a manner, via which slide member the respective inner slider segment 2a to 2e is coupled on the wedge element 13 such that the inner slider segments 2a to 2e are connected to the wedge element 13 in a positive-locking manner in a radial direction R, but the wedge element 13 is displaceable in the longitudinal direction LR of the longitudinal axis LZ relative to the inner slider segments 2a to 2e.

(21) The wedge element 13 is coupled with an adjusting device not represented here which pushes the wedge element 13 on corresponding control signals in the longitudinal direction LR along the longitudinal axis LZ into the inner slider 2 and pulls said wedge element 13 out of it. If the wedge element 13 is pushed into the inner slider 2, the inner slider segments 2a to 2e are displaced in the radial direction R away from the longitudinal axis LZ corresponding to the inclination of the wedge surfaces 13a, 13d of the wedge element 13 and the oblique surfaces 11a, 11d of the inner slider segments 2a to 2e abutting thereon until they have reached their shooting position approximated to the outer slider 3 (FIG. 1, 2). The mould cavity 5 is sealed by the outer slider 3 and inner slider 2 tightly from the environment in the shooting position.

(22) In the course of the displacement into the shooting position, gaps 16a to 16e running in the longitudinal direction LR are formed between the inner slider segments 2a to 2e which are also present in the region of the outer circumferential surface 6 of the inner slider 2 delimiting the mould cavity 5 on its inner side facing the inner slider 2. Owing to a suitable design of the inner slider segments 2a to 2e and a corresponding shaping of the foundry core G, these gaps 16a to 16e are, however, not disruptive.

(23) The moulding material provided for manufacturing the foundry core G is now shot into the mould cavity via shooting nozzles not represented here for the sake of clarity and then hardened in a manner known per se.

(24) To remove the finished foundry core G, the wedge element 13 is removed from the inner slider 2 such that the inner slider segments 2a to 2e coupled thereto are moved on the longitudinal axis LZ. This movement is carried out until the removal position of the inner slider segments 2a to 2e is reached, in which the gaps 16a to 16e are closed and the inner slider segments 2a to 2e abut closely on one another with their lateral surfaces (FIG. 3, 4). In this state, the inner slider segments 2a to 2e are separated from the finished foundry core G to the extent that the foundry core G can be removed in the longitudinal direction LR from the mould cavity 5, since the outer slider 3 has also been moved in the radial direction R away from it.

(25) To this end, the outer slider 3 is divided into seven outer slider segments 3a to 3g essentially shaped the same, with the longitudinal axis LZ also laying here in each of the dividing planes between the outer slider segments 3a to 3g, the dividing planes between the outer slider segments 3a to 3g also intersect in the longitudinal axis LZ. The outer slider segments 3a to 3g are moved on corresponding control signals in a direction aligned radially in relation to the longitudinal axis LZ from their shooting position approximated to the inner slider 2 into a removal position away from the inner slider 2 via an adjusting device not shown here, in which removal position the mould cavity 5 is opened to the extent that the foundry core G can be ejected from the mould cavity 5 in the longitudinal direction LR.

(26) In order to eject, the device 1 comprises a plurality of ejectors coupled in a manner known per se in their movement aligned in the longitudinal direction LR axially-parallel to the longitudinal axis LZ, which are also not visible here. The ejectors are guided in the base plate 4 in a manner known per se and in this case are formed and arranged such that the foundry core G, while the inner slider segments 2a to 2e and the outer slider segments 3a to 3g are moved in their respective removal position away from the foundry core G, is held on the ejectors. If the inner slider segments 2a to 2e and the outer slider segments 3a to 3g are located in their removal positions, the ejectors raise the finished foundry core G in the longitudinal direction LR from the mould cavity 5 such that it can for example be gripped by a gripper, also not shown here, and taken away.

(27) The device 100 shown in FIGS. 6 to 9 matches the device 1 in its basic structure. In the case of the device 100, as with the device 1, the inner slider 2 and the outer slider 3 are thus also divided into inner slider segments 2a to 2e and outer slider segments 3a to 3g in the same manner.

(28) One difference between the device 1 and the device 100 consists of the adjusting device provided for adjusting the inner slider segments 2a to 2e and the outer sliders 3a to 3g between their shooting and removal positions.

(29) The adjusting device thus comprises, in the case of the device 100, a disc-shaped control connecting rod 17, which is mounted rotatably flat on the underside of the base plate 4 abutting on the underside of the base plate 4. In this case, the rotary axis of the control connecting rod 17 coincides with the longitudinal axis LZ. A connecting rod guide 17a to 17e is in each case formed into the control connecting rod 17 for each of the five inner slider segments 2a to 2e.

(30) The connecting rod guides 17a to 17e arranged at even angular intervals distributed around the longitudinal axis LZ are in each case cut into the control connecting rod 17 as an arched slot. In this case, the connecting rod guides 17a to 17e are directed radially outwardly proceeding from their one end arranged closer to the longitudinal axis LZ and at the same time are vaulted convexly in the direction of the outer circumference of the control connecting rod 17 viewed in a top view.

(31) A guide pin 18a to 18e engages into each of the connecting rod guides 17a to 17e, of which one is in each case fastened on the underside of each of the inner slider segments 2a to 2e.

(32) Additional outer connecting rod guides 19a to 19g are formed into the control connecting rod 17 offset radially outwardly in relation to the connecting rod guides 17a to 17e. The connecting rod guides 19a to 19g are, in this case, formed with corresponding adaptation of their size proportions like the inner connecting rod guides 17a to 17e. A guide pin 20a to 20g is in each case guided into the outer connecting rod guides 19a to 19g. In each case one of the guide pins 20a to 20g is fastened to the underside of one of the outer slider segments 3a to 3g.

(33) If the control connecting rod 17 in the case of the arrangement of the connecting rod guides 17a to 17e, 19a to 19g shown in the FIGS. 7 and 9, is rotated on a corresponding control signal by means of a rotary drive of the adjusting device, not shown here, counter to the clockwise direction around the longitudinal axis LZ, the inner slider segments 2a to 2e coupled with said control connecting rod via the guide pins 18a to 18e engaging into the inner connecting rod guides 17a to 17e are moved towards the outer slider segments 3a to 3g. At the same time, the outer slider segments 3a to 3g coupled via the guide pins 20a to 20g engaging into the outer connecting rod guides 19a to 19g are also moved towards the inner slider segments 2a to 2e.

(34) The rotation of the control connecting rod 17 is stopped when the outer slider segments 3a to 3g and the inner slider segments 2a to 2e are moved into the shooting position approximating one another (FIG. 6, 7).

(35) If the control connecting rod 17 is, in contrast, rotated in the clockwise direction, the inner slider segments 2a to 2e are again moved into their removal position, in which they abut closely on one another with their lateral surfaces. The outer slider segments 3a to 3g are similarly moved into their removal position, in which they are moved maximally far away from the inner slider segments (FIG. 8, 9). The core closed in each case can now be ejected unobstructed from the device 100.

(36) FIGS. 6 to 9 and in particular FIG. 10 schematically show an example of how the inner slider segments 2a to 2e of the inner slider 2 could be configured such that the gaps 16a to 16e resulting between them when being displaced into the shooting position do not disrupt the manufacture of the foundry core G.

(37) The inner slider segments 2a, 2b shown there have, in each case, an upper longitudinal section 2a, 2b and a lower longitudinal section 2a, 2b. The lower longitudinal sections 2a, 2b are, in each case, offset in the circumferential direction UR with respect to the upper longitudinal section 2a, 2b such that the lower longitudinal section 2a, 2b in each case protrudes in the circumferential direction UR over the upper longitudinal section 2a, 2b with a offset 21 on the one side of the inner slider segment 2a, 2b in question and an equally large recess is formed on its opposing side.

(38) A correspondingly shaped and arranged recess 22 is formed into the region of the inner slider segment 2c assigned to the inner slider segment 2b such that the inner slider segment 2b engages with its offset 21 into the recess 22 of the inner slider 2c overlapping the upper longitudinal section 2c of the inner slider 2c. Similarly, the inner slider segment 2e has, on its side assigned to the inner slider segment 2a, an offset formed like the other offsets 21, which engages into the assigned recess 22 of the inner slider segment 2a. In the case of adjacent inner slider segments 2a, 2b; 2b, 2c; 2e, 2a, an offset 21 of the one inner slider segment 2a, 2b, 2e in each case consequently engages into a recess 22 of the in each case adjacent inner slider segment 2a, 2b, 2c.

(39) In this case, the heights of the offset 21 and the recess 22 are in each case adapted to one another such that the upper boundary surface of the respective recess 22 sits closely on the upper side of the offset 21 engaging into this recess 22. In this manner, regions overlapping one another in the region of the outer circumferential surface 6 of the inner slider segments 2a, 2b, 2c, 2e are formed, between which there are no open gaps, but rather only tight joints such that moulding elements to be represented on the foundry core G can be represented uninterrupted in spite of the gaps 16a, 16b, 16c present between the inner slider segments 2a, 2b, 2c and 2e.

(40) The inner slider segment 2d and the inner slider segments 2c and 2e adjoining inner slider segment 2d are configured in a different manner such that only closely closed gaps 16d, 16e are present in the shooting position between the inner slider segments 2c, 2d, 2e.

(41) To this end, vaultings 23, 24 are formed into the circumferential sides 2c and 2e of the inner slider segments 2c and 2e adjoining the assigned circumferential lateral surfaces 2d, 2d of the inner slider segments 2d in the circumferential direction UR, said vaultings extending over the height of the inner slider segment 2. The vaultings 23, 24 delimit a receiving portion 25 extending over the height of the inner slider segment 2 for the slider segment 2d in the inner slider segment 2.

(42) Vaultings 23, 24 are delimited in the radially outer-lying direction R by in each case a narrow edge section 2c and 2e of the inner slider segments 2c, 2e protruding in the circumferential direction UR in the direction of the inner slider segment 2d. The edge sections 2c and 2e, in the case of inner slider segments 2c to 2e being in the shooting direction, abut closely on the respectively assigned circumferential lateral surface 2d and 2d of the inner slider segment 2d.

(43) The vaultings 23, 24 and therefore the receiving portion 25 are, in this case, dimensioned and adapted in their shape to the shape of the circumferential lateral surfaces 2d, 2d and the dimensions of the inner slider segment 2d such that the inner slider segment 2d, in the case of inner slider segments 2c, 2e remaining in their shooting positions, can be freely moved into the receiving portion 25 in the direction of the central longitudinal axis LS of the inner slider 2 until it has reached its removal position. In this position, there is a gap between the circumferential lateral surfaces 2c and 2e of the inner slider segments 2c, 2e, on the one hand, and the circumferential sides 2d and 2d of the inner slider segment 2d, on the other hand, whose clear width is so great that the inner slider segments 2c, 2e can also then be pushed with the inner slider segments 2a, 2b in the direction of the central longitudinal axis LZ into their removal position. If the inner slider segments 2a, 2b, 2c, 2e have reached the removal position, all inner slider segments 2a to 2e abut with their circumferential lateral surfaces closely on the assigned circumferential surfaces of their adjacent inner slider segments 2a to 2e (FIG. 8).

(44) The movement into the shooting position then takes place in the reverse sequence.

LIST OF REFERENCE NUMERALS

(45) 1, 100 device for shooting foundry cores G 2 inner slider 2a to 2e inner slider segments 2a to 2e upper longitudinal section of the inner slider segments 2a to 2e 2a to 2e lower longitudinal section of the inner slider segments 2a to 2e 2d to 2d circumferential lateral surfaces of the inner slider segment 2d 2c, 2e circumferential sides of the inner slider segments 2c and 2e 2c, 2e edge sections of the inner slider segments 2c, 2e 3 outer slider 3a to 3d outer slider segments 4 base plate 5 mould cavity 6 outer circumferential surface of the inner slider 2 7 inner circumferential surface of the outer slider 3 8 central opening of the base plate 4 9a, 9d slotted guides 10a, 10d guide members 11a, 11d oblique surfaces of the inner slider segments 2a to 2e 12 upper side of the device 1 13 mandrel-like wedge element 13a, 13d wedge surfaces of the wedge element 13 14a to 14e T-groove guide of the inner slider segments 2a to 2e 15a to 15e T-groove guide of the wedge element 13 16a to 16e gaps 17 disc-shaped control connecting rod 17a to 17e inner connecting rod guides 18a to 18e guide pins 19a to 19g outer connecting rod guides 20a to 20g guide pins 21 offset 22 recess 23, 24 vaultings 25 receiving portion A recesses of the circumferential wall U G foundry core H height of the foundry core G I inner space of the foundry core G LR longitudinal direction LS central longitudinal axis of the foundry core G LZ central longitudinal axis of the inner slider 2 M local material accumulations of the circumferential wall U R radial direction S connection webs of the circumferential wall U T1 T5 dividing planes between the inner slider segments 2a to 2e U circumferential wall of the foundry core G UR circumferential direction projections of the circumferential wall U W clear width of the mould cavity 5