JP3255951B2 - Method and apparatus for molding a mold - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a molding tank which is accommodated in a filling tank and is moved by the filling tank to a molding station equipped with a mounting table, a model platen, a mold frame and a filling frame, and the molding station is used for the molding station. A method of molding a mold from sand-grained mold material delivered into the frame, particularly casting sand, and first discharge the classified fine-grained mold material onto a model, and then transfer the other mold material to the mold frame. The present invention relates to a molding method to be delivered and an apparatus for performing the method.

[0002]

2. Description of the Related Art When molding a mold from a sandy mold material that is compressed on a model in a mold frame, it is crucially important that the model is sharply transferred to the mold material. is there. Furthermore, the density and hardness of the mold material in the mold area close to the model are also important. The mold material, in particular, must have good sandy flowability and a relatively fine particle size as uniform as possible. It is particularly important to adhere to the above requirements, since the mold material must be reused after it has been cast into the flask for cost and environmental protection reasons and must be prepared for this reuse. The prepared mold material is therefore finely ground into the form of flowable sand. Nevertheless, it is inevitable that the particle size distribution becomes non-uniform, in particular, a relatively large agglomerate of the mold material remains. Also, in any case such agglomerations may be reformed and augmented during the transfer of the mold material, so that the classification step (sieving) incorporated into the process of preparing the mold material is a conditional aid. It just becomes.

[0003] The mold material is conveyed by a conveying device to a molding device, and in some cases is transferred to a filling tank via an intermediate buffer zone such as a bunker. In the present molding machine, the filling tank and the compressor device are arranged so as to be able to run on a mounting table equipped with a mold frame, and can be selectively moved into the molding station. It is brought upwards to discharge the required amount of mold material into the flask and the compressor device is then moved above the flask to compress the mold material in the flask. During this phase of operation, the filling tank reaches the filling position.

[0004] In order to avoid the agglomeration of the mold material (lumps) in the flask, stirring is carried out by a loosening device just before the mold material is transferred to the flask, thus disassembling the mold material mass. No. 7,760,311, German Patent 544,268 and German Patent 606043.

[0005] A relatively loose agglomerate can be decomposed by such a loosening device, but an agglomerate having a relatively large caking force cannot be loosened. In any case, however, the known loosening devices require a corresponding residence time of the mold material in the filling tank or in the bunker preceding the filling tank. Such dwell times can no longer be matched to the high working cycles of today's molding equipment. The duration of the stay can be shortened by a correspondingly powerful loosening exercise, but this shortening requires a high energy consumption and ultimately a completely satisfactory result. I can't.

[0006] In most cases, special requirements are imposed on the quality of the mold material in the area close to the mold model. In order to satisfy this, a so-called "model sand" is first set on the model. The setting of this model sand was previously done by hand. In a mechanized molding machine, a sieving station is already arranged outside the molding station, and the flask is brought to the sieving station together with the model platen before the flask enters the molding station. In the sieving station, the model sand is sieved on the model by vibrating sieve. The sieving residue (sieving residue) is discarded.
Even if the loosening operation is insufficient, the sieving amount is negligible, and the cycle time of the molding apparatus is significantly increased. In addition, the construction costs are high and the space requirements are large.

[0007]

SUMMARY OF THE INVENTION An object of the present invention is to provide a molding method and a molding apparatus which can mold a mold having a satisfactory mold contour and uniform quality in a short cycle time.

[0008]

The method of the present invention for solving the above-mentioned problem is that a part of the mold material sufficient to coat at least the surface of the model is supplied before or before delivery to the flask. During the delivery for molding, the material is sieved and classified in a filling tank, delivered to the flask as a sieved portion, and the remaining amount as the unsieved portion is delivered directly to the flask.

According to the method of the present invention, at least a partial amount of the mold material contained in the filling tank is first classified. That is, this classification means that the classification is limited to a particle size corresponding to the mesh width of the sieve. The high quality requirements imposed here are met by the relatively fine mold material particle size and the uniform particle size distribution, since this partial quantity first enters the flask and thus first reaches the model surface. Theoretically, it is also possible to sieve and classify the total required amount of mold material required for one mold frame, but this generally leads to an excessively long time. Therefore, a sufficient amount to cover the surface of the model is classified as "model sand" and the remaining amount of the remaining sieve is transferred directly into the flask. In this case, the invention implies that the quality requirements imposed on the mold material outside the area close to the model surface are not so high, so that the mold material with a relatively coarse grain size in the area not close to the model surface Starting from the known fact that particles as well as agglomerates may be present. Since only a relatively small amount is required to coat the model surface, it is possible to easily incorporate the sieving operation into the mechanical cycles normally performed today. The invention also discloses that, in addition to the above, in the case of less demanding quality molds, the total required amount of mold material can be discharged directly into the flask without a classification operation.

[0010] In some cases, it is also possible to loosen the mold material during the sieving operation to cause a crushing operation on one side and to facilitate classification on the sieving side on the other.

It is particularly advantageous when a part of the mold material is classified and collected during the traveling movement of the filling tank from the preparation position to the molding station, and is delivered to the mold frame after reaching the molding station. An operation mode is obtained.

[0012] In this way, the mold material required to cover the outer contour of the model is produced during the waste time that is present anyway (during the running movement of the filling tank) and at the molding station. At the moment the filling tank arrives at the desired amount.

[0013] In order to solve the above-mentioned problems, the present invention provides an apparatus according to the present invention, wherein the filling tank has a sieve for retaining the mold material and a movement device for loosening the mold material, and the sieve comprises:
The point is that it is configured to be movable to a position where the unsieved portion is transferred into the flask.

The proposed sieve according to the invention for producing "model sand" forms at least a part of the filling tank and is designed to contain the mold material. The exerciser for the mold material agitates and loosens the mold material located on the sieve surface, while at the same time promoting the passage of relatively fine mold material particles through the sieve. If the height of the model or the height of the flask is small, it is possible in some cases to classify the total required amount of mold material. In most cases, however, only a partial quantity is classified and the remainder of the sieve is transferred directly into the flask by a corresponding movement of the sieve.

In a preferred embodiment of the device according to the invention, the sieve is configured as a horizontally pivoted cylindrical sieve,
In addition, the peripheral wall has an opening.

By arranging the sieve arranged in the filling tank as a cylindrical sieve, a relatively large amount of mold material, in particular, the total amount required for one mold frame is accommodated in the sieve,
The mold material can be loosened by a motion device that circulates about the bearing axis. Further, the cylindrical sieve is
By turning around the axis, the mold material can be easily opened in the mold frame, so that even when relatively fine model sand is not required, the total amount of the mold material can be extremely short from the filling tank. It is possible to deliver to the flask in time.

The opening of the cylindrical sieve has an included angle in the angular range of at least 90 ° in order to ensure a quick and complete emptying of the mold material from the filling tank. This also facilitates the transfer of the mold material to the cylindrical sieve.

In a preferred embodiment of the invention, the cylindrical sieve consists of two partial cylindrical shells, wherein both partial cylindrical shells have two cylindrical shells.
In the form of a sector shutter, it is selectively pivotable between a closed position forming a sieve and an open position which will be located substantially outside the drop path of the mold material. With this configuration, if necessary, i.e., if it is not necessary to use the sand classified by sieving, it is possible to transfer the casting material directly from the cylindrical sieve into the casting mold, in which case both Are swiveled away from each other from the closed position, so that the mold material falls directly onto the bottom closure of the filling tank and is ready for transfer to the flask. The exercise device remains stationary in this case.

Furthermore, when the model sand is classified first, the remaining portion of the sieve after the sieving operation is performed by rotating the two partial cylindrical shells away from each other, that is, by opening the two-sector type shutter. The working cycle time is further reduced since the mold is released very quickly into the flask.

To screen on one side in the closed position, ie to ensure that the two partial cylindrical shells have a sufficiently large capacity, and to ensure on the other side that the two partial cylindrical shells are positioned outside the falling path of the mold material. Each sub-cylindrical shell extends over an arc angle of about 90 °, ie, each has the shape of a quarter-cylindrical shell.

According to an advantageous embodiment, in a cylindrical sieve,
An exercise device is arranged which circulates or oscillates about the bearing axis of the cylindrical sieve, which can have, for example, a plurality of strips rubbing the sieve surface. The strip itself is advantageously arranged on a rotating cross which is driven by the bearing shaft of a cylindrical sieve.

The stirring and loosening action of the mold material is assisted by a plurality of short strips arranged one after the other in the direction of extension of the cylindrical sieve, said short strips being Advantageously, it is set at an angle to the bearing axis of the sieve.

Particularly short sieving times and good loosening of the mold material are obtained when the strip is designed as a brushed strip.

In a further advantageous embodiment, a collecting device is arranged at a distance below the sieve for receiving a classified portion of the mold material, the collecting device being provided in the flask with the said portion. Is configured to be released.

In particular, the above-described embodiment makes it possible to sift and classify the desired or required part of the mold material during the running movement of the filling tank, in which case the latter is used during the running movement of the molding machine. It cannot fall on other parts. The collection device is configured to receive a portion of the mold material and to discharge the portion into the flask at a molding station.

The collecting device can be configured as a multi-blind shutter. In that case, as long as the cylindrical sieve is arranged inside the filling tank, the shutter may be a conventional multi-blind shutter of the filling tank.

Instead of the multi-blind shutter, it is also possible to configure the collecting device in the form of a two-sector shutter that opens and closes like a snout of a fish, and the two-sector shutter is located below the cylindrical sieve. It is arranged concentrically and closes the filling tank from below.

[0028]

Next, an embodiment of the present invention will be described in detail with reference to the drawings.

The molding apparatus shown in FIG. 1 has a compressor device 1 in the form of, for example, an air shock wave generating unit and a filling tank 2. The air shock wave generating unit and the filling tank are both in the plane of the drawing by, for example, a common carriage 3. It is possible to travel. A filling frame 4 is arranged below the compressor device 1. Below the filling frame, a roller table 7 for transferring a mold frame 8 moving through the molding station from the left hand to the right hand in the drawing is arranged. Below the roller table 7 is located a mounting table 6 having a rotating disk 5, which in the exemplary embodiment receives, for example, two model stools for one upper frame and one lower frame, Therefore, the upper frame model and the lower frame model are alternately raised by the molding apparatus.

In the embodiment shown, the filling tank 2 is charged via a belt conveyor 9. As an alternative, it is also possible to provide a storage bunker in which the mold material is delivered via a belt conveyor 9. A sieve 10 is arranged inside the filling tank 2, and the sieve restrains the mold material delivered into the filling tank.

2 to 7, the sieve 10 is designed as a cylindrical sieve and has an opening 11 in its peripheral wall.
have. The opening has a included angle of at least 90 °. In the filling position, the opening 11 is located below the hopper-like inlet 12 of the filling tank 2.

A rotary cross (not shown) is mounted on the drive shaft 13 inside the cylindrical sieve 10, the rotary cross comprising a plurality of strips, which are particularly preferably configured as brushed strips. 14 is provided. The brushed strip scrapes the inner surface of the cylindrical sieve and agitates the mold material contained in the cylindrical sieve 10. By the movement of the strip 14, the fine particles of the mold material are classified by the cylindrical sieve 10 and passed through the sieve 17
2 (see FIG. 2), which is configured as a multi-blind shutter in the filling tank 2 in the embodiment shown in FIGS.

The sieve 1 placed on the collecting device 16
7 (this sieving occurs, for example, during the running movement of the filling tank 2 from the position shown in FIG. 1 to the molding station)
When the multi-blind shutter is opened at the molding station, the shutter is discharged into the flask 8 or the filling frame 4 placed on the flask (FIG. 3). Thus, the model surface is first covered with the mold material. Then, the cylindrical sieve 10 is rotated by 180 °, so that the unclassified mold material 15 still contained in the cylindrical sieve reaches the flask 8 (FIG. 4).

The embodiment shown in FIGS. 5 to 7 is different from the embodiment shown in FIGS. 2 to 4 only in that the configuration of the collecting device 16 is different. Collection device 16 of the present embodiment
Is configured as a two-sector shutter that opens and closes in a snout-like shape of a fish having two opening / closing jaws 18. Both opening / closing jaws are arranged concentrically on the drive shaft 13, and
Can be swung from the position for retaining the sieve portion 17 shown in FIG. 6 to the open position shown in FIG. Then, the cylindrical sieve 10 is rotated to the position shown in FIG. 7 and the remaining sieve is discharged to fill the flask 8. Incidentally, also in this case, the collecting device 16 forms a lower closed portion of the filling tank 2.

The embodiment shown in FIGS. 8 and 9 shows a variation of the cylindrical sieve according to the embodiment shown in FIGS. In this case, the cylindrical sieve 10 consists of two partial cylindrical shells 10a, which form a semi-cylindrical body in the closed position shown in FIG. The two partial cylindrical shells 10a are rotatably mounted concentrically with respect to the drive shaft 13 and are pivotable to the open position shown in FIG. Are released both up and down and are substantially outside the drop path of the mold material.

The partial cylindrical shell 10a has, on one side,
In order to allow the mold material charged from above into the filling tank 2 to reach the collecting device 16 and thus the model without being subjected to a sieving operation, it may occupy the open position shown in FIG. it can. On the other side, the cylindrical sieve 10 is shown in FIG.
After completion of the sieving operation shown in FIG.
It can be opened by turning Oa upward. Also, in the case of the embodiment shown in FIGS. 5 to 7, it is also possible to use a cylindrical sieve 10 composed of two partial cylindrical shells 10a as shown in FIGS. In this case, both the cylindrical sieve 10 and the collecting device 16 are configured as a two-sector type shutter having an opening / closing jaw 18 that can pivot upward. Moreover, the opening and closing jaws 18 are arranged concentrically and driven by a common driving device.

[Brief description of the drawings]

FIG. 1 is a schematic side view of a molding apparatus.

FIG. 2 is a view showing a first operation position of a filling tank according to one embodiment.

FIG. 3 is a view showing a second operation position of the filling tank shown in FIG. 2;

FIG. 4 is a view showing a third operation position of the filling tank shown in FIG. 2;

FIG. 5 shows a first operating position of the filling tank according to an embodiment different from that of FIG. 2;

FIG. 6 is a view showing a second operation position of the filling tank shown in FIG.

FIG. 7 is a view showing a third operation position of the filling tank shown in FIG.

FIG. 8 is a view showing a closed position of a variation of the filling tank shown in FIGS. 2 to 4;

FIG. 9 is a view showing an open position of the filling tank shown in FIG.

FIG. 10 is a view showing a closed position of a variation of the filling tank shown in FIGS. 5 to 7;

FIG. 11 is a view showing an open position of the filling tank shown in FIG.

[Explanation of symbols]

1 compressor unit, 2 filling tank, 3 common carriage, 4 filling frame, 5 rotating disk,
6 mounting table, 7 roller table,
8 mold flask, 9 belt conveyor, 10 cylindrical sieve, 10a partial cylindrical shell, 11 opening,
12 hopper-shaped inlet, 13 drive shaft, 14
Strip, 15 mold material, 16 collector,
17 for sieving, 18 opening and closing jaws

──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Norbert Dam Germany Germany Karlsdorf Neuthard Büchenauer Strasse 22 (72) Inventor Thomas Pal Germany Karlsruhe 41 Marstalstrasse 12 B (58) Investigated Field (Int. Cl. ⁷ , DB name) B22C 11/00-25/00 B22C 9/02 101 B22C 5/12 B22C 5/06 EPAT (QUESTEL)

Claims (18)

(57) [Claims] 1. A molding tank which is housed in a filling tank and is moved by the filling tank to a molding station equipped with a mounting table, a model platen, a mold frame and a filling frame, and is delivered into the mold frame at the molding station. Sand-granular casting such as foundry sand
In a method of molding a mold from a mold material, the classified fine-grained mold material is first released onto a model, and then the other mold material is delivered to a mold frame. At least a portion of the mold material sufficient to be coated is sieved and classified in a filling tank before delivery to the flask or during delivery for the preceding molding, delivered to the flask as a sieve pass, and sieved. A molding method of a mold, characterized in that a remaining amount as a residue is directly transferred into a mold frame. 2. The molding method according to claim 1, wherein the mold material is loosened during the sieving operation. 3. The method according to claim 1, wherein a portion of the mold material is sieved to classify and collect during the traveling movement of the filling tank from the preparation position to the molding station, and after reaching the molding station, is transferred to the mold frame. 2. The molding method according to 2. 4. A mold filling station having a movable filling tank for mold material, a mounting table, a model platen, a mold frame, a filling frame and a compressor device for mold material, and delivering a fine-grained mold material onto the model. and a sieve for, cast
In an apparatus for molding a mold from a sandy mold material such as material sand , a filling tank (2) includes a sieve (1) for retaining the mold material.
0) and exercise equipment for loosening the mold material (13, 14)
And the sieve (10) is configured to be movable to a position for delivering the unsieved portion (15) into the flask (8). 5. The molding apparatus according to claim 4, wherein the sieve (10) is arranged in the filling tank (2). 6. The sieve is a cylindrical sieve (1) supported horizontally.
0) and an opening (11) in the peripheral wall
The molding apparatus according to claim 4, further comprising: 7. The molding apparatus according to claim 6, wherein the opening has a bevel angle in an angle range of at least 90 °. 8. A cylindrical sieve (10) comprising two partial cylindrical shells (10a), both partial cylindrical shells in the form of a two-sector shutter, a closed position forming a sieve, and substantially a drop of mold material. The molding apparatus according to claim 6 or 7, wherein the molding apparatus is configured to be selectively pivotable to an open position that is located outside the path. 9. The molding apparatus according to claim 8, wherein each partial cylindrical shell extends over an arc angle of about 90 °. 10. A motion device (1) circulating or oscillating around a bearing axis of a cylindrical sieve (10) in a cylindrical sieve (10).
The molding apparatus according to any one of claims 6 to 9, wherein (3, 14) is arranged. 11. The molding device according to claim 4, wherein the exercise device has a plurality of strips rubbing the sieve surface. 12. The molding device according to claim 11, wherein the strips (14) are arranged on a rotating cross. 13. The molding device according to claim 6 , wherein a plurality of short strips are arranged alternately one after the other in the axial direction of the cylindrical sieve. 14. The short strip (14) has a cylindrical sieve (10).
The molding apparatus according to any one of claims 6 to 13, wherein the molding apparatus is set at an angle with respect to the support axis. 15. strip (14) is configured as a brushed strips, one of claims 11 to 14 1
The molding apparatus according to the above item. 16. A collecting device (16) for receiving a classified portion (17) of mold material is arranged at a distance below the sieve (10), the collecting device comprising a mold frame. The molding apparatus according to any one of claims 4 to 15, wherein the apparatus is configured to discharge the partial amount to (8). 17. The molding device according to claim 16 , wherein the collecting device is configured as a multi-blind shutter. 18. The molding device according to claim 16 , wherein the collecting device is configured as a two-sector shutter.