US20170014896A1

US20170014896A1 - Feeder Insert For A Vertically Split Casting Mold

Info

Publication number: US20170014896A1
Application number: US14/901,992
Authority: US
Inventors: Thomas Schaefer; Tobias Hesse
Original assignee: GTP Schaefer Giesstechnishe Produkte GmbH
Current assignee: Roche Diagnostics GmbH; GTP Schaefer Giesstechnishe Produkte GmbH
Priority date: 2013-07-02
Filing date: 2014-07-01
Publication date: 2017-01-19
Also published as: DE112014003099A5; WO2015000866A1; CN105531053A

Abstract

A feeder insert (10) for use in a vertically split casting mold that is used for the casting of metals includes a feeder body (11), which has an internal cavity (12) as feeder volume and which is composed of an exothermic and/or insulating material and which, in the base surface (17) thereof, which faces toward a pattern inserted into the casting mold during production of the casting mold, has a feeder opening (18) for connecting the cavity (12) to the mold cavity of the casting mold, wherein the feeder body (11) is oriented with its longitudinal axis (21), which runs through the feeder opening (18), at an angle with respect to the vertically oriented pattern and so as to be horizontal relative to the pattern, and the volume of the internal cavity (12) is of asymmetrical design with respect to an imaginary parting plane (25) running in or parallel to the longitudinal axis (21), characterized in that the feeder body (11) has an uneven mass distribution with respect to the parting plane (25), with a center of mass situated to one side of and spaced apart from the parting plane (25), and that region (28) of the internal cavity (12) of the feeder body (11) which is situated on that side of the parting plane (25) which is situated opposite the center of mass has a larger volume than that region (29) of the internal cavity (12) which is situated on that side of the parting plane (25) which faces toward the center of the mass.

Description

The invention relates to a feeder insert for use in a vertically split casting mold that is used for the casting of metals includes a feeder body, which has an internal cavity as feeder volume and which is composed of an exothermic and/or insulating material and which, in the base surface thereof, which faces toward a pattern inserted into the casting mold during production of the casting mold, has a feeder opening for connecting the cavity to the mold cavity of the casting mold, wherein the feeder body is oriented with its longitudinal axis, which runs through the feeder opening, at an angle with respect to the vertically oriented pattern and so as to be horizontal relative to the pattern, and the volume of the internal cavity is of asymmetrical design with respect to an imaginary parting plane running in or parallel to the longitudinal axis.
A feeder insert with the above-noted features is known from EP 2 489 450 A1. This feeder insert is already provided and equipped for insertion into a vertically split casting mold. Such a vertically split casting mold is known and provided, for example, in WO 2010/041091 A1. In the frame of manufacturing of these types of casting molds by means of a correspondingly equipped mold assembly, described in WO 2010/041091 A1, the feeder insert upon manufacture of the casting mold is oriented on a vertically extending pattern or a corresponding pattern plate and shaped into a quasi-horizontal orientation in the casting mold, so that its feeder opening likewise is oriented substantially vertically. With this type of orientation of the feeder insert, the problem is that when filling the mold cavity that occurs in the molding process by delivery of the liquid metal from the inner cavity of the feeder body based on the volume contraction during the setting process of the metal in the mold cavity, the liquid level of the liquid metal in the inner cavity of the feeder body can drop to such an extent that the cross section of the vertical feeder opening no longer is covered completely by liquid metal. This can have the result that the region of the already cast-in mold cavity of the casting mold, connected to the feeder body and connected with its feeder opening, empties into the inner cavity of the feeder insert. Furthermore, the feeder module of the feeder insert is reduced, as far as the inner cavity of the feeder body is emptied too much during the feeding process.
In order to counteract this problem, with the feeder insert described in EP 2 489 450 A1, it is provided that the feeder opening of the feeder insert is displaced eccentrically downwards, relative to the longitudinal central axis of the feeder body, whereby the volume of the inner cavity above the feeder opening is greater than the volume present below the feeder opening. In addition, the feeder body can be tilted upwardly with its longitudinal axis also from the horizontal. In this connection, the results should be that the feeder opening is covered during the molding process, respectively, by the liquid metal available in the inner cavity. The known feeder insert, in addition, has a so-called Williams core in the form of a projection formed on a wall region surrounding the inner cavity and projecting with its tip into the inner cavity. This Williams core is arranged in the region of the inner cavity of the feeder insert that is positioned above the feeder opening and which has the greater volume.
The known feeder insert has the disadvantage, however, that the feeder body is fixed to the pattern based on its design, respectively, in the correct orientation or direction. As far as the feeder body being inserted onto a mold pin located on the pattern, it is proposed in EP 2 489 450 A1 to provide positive locking between the mold pin and the feeder body, in order to permit, respectively, the correct orientation of the feeder body to the pattern carrying the mold pin. Nevertheless, during orientation of the feeder insert, errors are not completely eliminated.
A feeder assembly is disclosed in SU 776 740 A1, in which a feeder head is formed with a cavity serving to receive liquid metal and positioned above a feeder insert formed vertically in a casting mold in which mold sand is placed for formation of the casting mold. A likewise vertically oriented Williams core projects from a side wall of the feeder head into the cavity, whose lower surface facing the feeder insert is spaced relative to the feeder insert and runs parallel thereto. This type of configuration is not suitable for a horizontal arrangement and a corresponding design of the feeder assembly in the casting mold.
The present invention is therefore based on the object of providing a feeder insert with the above described types of features, such that an incorrect or inaccurate orientation of the feeder insert, during casting in a vertically split casting mold, is avoided and simultaneously, the advantage of a complete feeding of the mold cavity is maintained.
The solution of this object is provided from the content of the patent claims, which follow this description, and which include the advantageous embodiments and improvements of the invention.
The invention contemplates that the feeder body has an uneven mass distribution with respect to the parting plane with a center of mass situated to one side of and spaced apart from the parting plane and that region of the internal cavity of the feeder body which is situated on that side of the parting plane which is situated opposite the center of mass has a larger volume than that region of the internal cavity which is situated on that side of the parting plane which faces toward the center of mass.
The present invention offers the advantage that the feeder insert, based on the uneven mass distribution, is oriented automatically during casting. If a feeder insert formed according to the present invention is mounted, for example, on a mold pin during assembly of the casting pattern, then the feeder insert rotates automatically, based on the uneven mass distribution, into a position in which the larger volume portion of the internal cavity lies above the longitudinal axis of the feeder body running through the feeder opening. Thus, it must be ensured that the stored volume of liquid metal above the feeder opening is increased and sufficiently dimensioned for the feeding process so that the feeder insert during the feeding process does not run empty. Simultaneously, in this connection, the cross section of the feeder opening is covered, respectively, by liquid metal contained in the internal cavity of the feeder body.
According to one embodiment of the invention, it is provided that the uneven mass distribution is realized by the formation of different wall thicknesses on the feeder body, whereby the region of the wall area positioned beneath the parting plane with a horizontal orientation of the feeder body on the vertical pattern has a greater wall thickness than the region of the wall area of the feeder body positioned above the parting plane.
The invention can be realized with feeder inserts, with which the longitudinal axis of the feeder opening forms the center axis of the feeder body. Alternatively, however, a design of the feeder insert is possible, in which the longitudinal axis of the feeder opening is arranged eccentric to the center axis of the feeder body, which is already known from the disclosure of EP 2 489 450 A1.
Furthermore, it can be provided that the feeder body has, in its cover region that is disposed opposite to the base surface, an opening that is aligned with the feeder opening and disposed in the longitudinal axis running through the feeder opening for receiving a mold pin secured to the pattern inserted in the mold, so that the feeder insert can be shifted already before casting over the mold pin, so that the feeder insert during the casting process cannot be slid out of it. During the casting process, the feeder insert is displaced then still further in the direction of the longitudinal center axis of the feeder insert or of the pin supported in it in the direction of the pattern carrying the mold pin. Thus, in a known manner, the feeder insert can be mounted on a rigid mold pin or also on another so-called spring pin.
For example, based on manufacturing grounds, it can be provided that the feeder body can comprise two halves that are separated along a transverse axis running at a right angle to its longitudinal axis and connected to form the feeder body.
According to one embodiment of the invention, it is provided that a shaped part, preferably made of metal and having a through-opening that is aligned with the feeder opening of the feeder body, is fixed to the base surface of the feeder body, as is known from EP 2 489 450 A1. In this regard, the shaped part fulfills the same object as a feeder insert used in a horizontally split casting mold.

In the figures, exemplary embodiments of the present invention are shown, which are described below. In the drawings:

FIG. 1 shows a feeder insert in a position associated with a vertical mold form half in a lateral sectional view,

FIG. 2 shows the subject matter of FIG. 1 with a mold part forming its feeder foot.

The feeder insert 10 shown in FIG. 1 has a feeder body 11, which includes a wall area 13 surrounding an internal cavity 12 as a so-called feeder volume and a cover region 14. The feeder body has an outer surface 16 and an inner surface 15 of the wall area 13 surrounding the inner cavity 12 as well as a base surface 17, in which a feeder opening 18 is formed.
The feeder insert 10 shown in a “horizontal” arrangement should be associated with a vertical casting mold half 20, whereby the feeder insert can be mounted on a mold pin (not illustrated) formed on a pattern inserted in the casting mold. The mold pin engages through the feeder opening 18 into the base surface 17 and extends into the cover region 14 of the feeder insert 10, whereby in this cover region 14, an opening 22 for receiving the tip of the mold pin is formed. During casting, the tip of the mold pin could puncture the remaining cross section of the cover region in the opening 22. This, however, is also known from the state of the art.
It is clearly recognizable that the region 26 of the wall area 13 disposed above an imaginary parting plane 25, which coincides with the longitudinal axis 21 of the feeder opening 18, which in the embodiment shown in the drawing, forms simultaneously the longitudinal center axis of the feeder body 11 and extends into the plane of the drawing, has a clearly thin material thickness and therefore, markedly less mass than the region 27 of the wall area 13 disposed below the parting plane 25, so that the center of mass (which is not specifically defined in the drawing) of the entire wall area 13 of the feeder insert 10 lies, if necessary, below the parting plane 25. This has the result that the feeder insert 10 after mounting onto a mold pin, before compression of the mold material applied into the casting mold, necessarily rotates into such a position, in which the heavier region 27 of the wall area 13, based on the effects of gravity, is lying always below the parting plane 25 of the longitudinal axis of the mold pin.
At the same time, the internal cavity 12 of the feeder insert with reference to the longitudinal axis 21 is asymmetrically formed, whereby the region 28 of the internal cavity 12 positioned on the side of the parting plane 25 opposite to the center of mass has a greater volume that the region 29 of the hollow cavity positioned on the side of the parting plate 25 facing toward the center of mass. Since as described, the feeder insert 10 upon mounting onto a mold pin is oriented such that the heavier region 27 of the wall area 13 is positioned below the longitudinal axis of the mold pin, this necessarily results in the region 28 of the internal cavity 12 with the greater volume lying above the longitudinal axis 21 of the parting plane 25. Thus, it is ensured that based on additional and upwardly displaced volume of the internal cavity 12, compared to typical symmetrical feeder inserts, the volume of liquid metal to be received by the feeder inserts 10 can be increased to the point that the volume for one feed is dimensioned sufficiently without the feeder insert 10 running empty and its feeder opening 18 is kept clear.
From FIG. 1, it can further be seen that based on grounds of a more simple manufacturing, the feeder body 11 comprises two halves 11 a, 11 b separated along a transverse axis 23 running at a right angle to its longitudinal axis 21 and connected to form the feeder body 11, which can be manufactured as individual parts, respectively.
The embodiment shown in FIG. 2 differs from the previously described embodiment merely in that on the base surface 17 of the feeder insert 10, a preferably metallic shaped part 30 is arranged and is connected with the base surface 17, preferably by an adhesive, which has a hat-shaped or also cylindrical design and has a through-opening 31 aligned with the base opening 17 of the feeder insert 10. This type of design including such a shaped part 30, which also can be formed to be deformable, corresponds in this regard with the related state of the art. The features of the subject matter of this specification disclosed in the foregoing description, the patent claims, the abstract and the drawings can be important individually as well as in any combination with one another for realization of the present invention in its various embodiments.

Claims

1-7. (canceled)

8. A feeder insert (10) for use in a vertically split casting mold that is used for the casting of metals, comprising:

a feeder body (11) having an internal cavity (12) as feeder volume, wherein said feeder body (11) is composed of an exothermic and/or insulating material, said feeder body (11) having a base surface (17). wherein said base surface (17) faces toward a vertically oriented pattern inserted into the casting mold during production of the casting mold, said base surface (17) having a feeder opening (18) for connecting the internal cavity (12) to a mold cavity of the casting mold, wherein the feeder body (11) has a longitudinal axis (21) running through the feeder opening (18) and is oriented with said longitudinal axis (21) at an angle with respect to the vertically oriented pattern and so as to be horizontal relative to the pattern,

wherein the volume of the internal cavity (12) is of asymmetrical design with respect to an imaginary parting plane (25) running in or parallel to the longitudinal axis (21),

wherein the feeder body (11) has an uneven mass distribution with respect to the parting plane (25), with a center of mass situated to one side of and spaced apart from the parting plane (25), and wherein a region (28) of the internal cavity (12) of the feeder body (11) that is situated on a side of the parting plane (25) which is situated opposite the center of mass has a larger volume than a further region (29) of the internal cavity (12) which is situated on a side of the parting plane (25) that faces toward the center of mass.

9. The feeder insert according to claim 8, wherein the uneven mass distribution is realized by formation of different wall thicknesses on the feeder body (11), whereby the region (27) of the wall area (13) disposed beneath the parting plane (25) with a horizontal orientation of the feeder body (11) relative to the vertically oriented pattern has a greater wall thickness than the region (26) of the wall area (13) of the feeder body (11) disposed above the parting plane (25).

10. The feeder insert according to claim 8, wherein the longitudinal axis (21) of the feeder opening (18) forms a central axis of the feeder body (11).

11. The feeder insert according to claim 8, wherein the longitudinal axis (21) of the feeder opening (18) is arranged eccentric to a central axis of the feeder body (11).

12. The feeder insert according to claim 8, wherein the feeder body (11) includes a cover region (14), wherein said cover region (14) is disposed opposite to the base surface (17) and includes an opening (22) that is aligned with the feeder opening (18) and disposed in the longitudinal axis (21) running through the feeder opening (18) for receiving a mold pin secured to the vertically oriented pattern inserted in the mold.

13. The feeder insert according to claim 8, wherein the feeder body (11) comprises two halves (11 a, 11 b) divided along a transverse axis (23) running at a right angle to the longitudinal axis (21) of the feeder opening (18), wherein said two halves (11 a, 11 b) are assembled to form the feeder body (11).

14. The feeder insert according to claim 8, further comprising a shaped part (30) having a through opening (31) that is aligned with the feeder opening (18) of the feeder body (11), wherein said shaped part (30) is fixed to the base surface (17) of the feeder body (11).

15. The feeder insert according to claim 14, wherein the shaped part (30) is made of metal.