Sand moulding chamber for vertical sand moulding machine, method of producing such chamber and set of wear plates for use in lining the sand moulding chamber

Abstract

The sand moulding chamber (1) includes a chamber top wall (3), a chamber bottom wall (4), and two opposed chamber side walls (5, 6), wherein an internal side of each said chamber wall is provided with a machined contact face (9) for attachment of a wear plate, wherein an external side of the sand moulding chamber forms a number of tie rod bearing extensions (15) having bores (16) for tie rod guide bushings for guiding, in a longitudinal direction of the sand moulding chamber, respective tie rods of a compacting system of a vertical sand moulding machine, and wherein each tie rod bearing extension includes a machined contact face (20) for the respective tie rod guide bushing. The chamber top wall, the chamber bottom wall, and the two opposed chamber side walls together form a main chamber element (21) made from one single metal casting.

Description

[0001] P3624PC00

[0002] 1

[0003] SAND MOULDING CHAMBER FOR VERTICAL SAND MOULDING MACHINE AND METHOD OF PRODUCING SUCH CHAMBER

[0004] The present invention relates to a sand moulding chamber for a vertical sand moulding machine for the production of sand mould parts, wherein the sand moulding chamber includes at least a chamber top wall, a chamber bottom wall, and two opposed chamber side walls, wherein all said chamber walls extend in a longitudinal direction of the sand moulding chamber and all said chamber walls are formed of cast metal, wherein at least one of said chamber walls is provided with at least one sand filling opening, wherein at least part of an internal side of each said chamber wall is provided with at least one machined contact face for attachment of a wear plate, wherein an external side of the sand moulding chamber forms a number of tie rod bearing extensions having bores for insertion of tie rod guide bushings for guiding, in the longitudinal direction of the sand moulding chamber, respective tie rods of a compacting system of the vertical sand moulding machine, and wherein each tie rod bearing extension includes at least one machined contact face for contacting the respective tie rod guide bushing.

[0005] EP 2349611 Bl (Disa Industries A / S) discloses a moulding machine operating by the vertical moulding technique. The moulding machine comprises a moulding chamber delimited by a top wall, two side walls and a bottom wall.

[0006] In prior art vertical sand moulding machines, the sand moulding chamber is assembled from four separate castings forming the top wall, the two side walls and the bottom wall, respectively. Before assembling these separate castings, each casting is installed individually in a machining centre, in which an internal side of the chamber wall is machined to form a contact face for attachment of a wear plate, and in which contact faces for contacting neighbouring chamber walls are machined. Subsequently, the four chamber walls are screwed together, and the assembled chamber unit is installed in a machining centre, wherein the separate parts are further connected by means of pin fasteners to form one unit. This one unit is subsequently machined to form contact faces for contacting respective tie rod guide bushings. However, this procedure is cumbersome and consequently costly. P3624PC00

[0007] 2

[0008] The object of the present invention is to provide a sand moulding chamber which is simpler to manufacture and which may provide even more accurately aligned contact faces for wear plates and tie rod guide bushings.

[0009] In view of this object, at least the chamber top wall, the chamber bottom wall, and the two opposed chamber side walls together form a main chamber element made from one single metal casting.

[0010] In this way, by providing one single metal casting forming at least the chamber top wall, the chamber bottom wall, and the two opposed chamber side walls, the steps of machining each chamber wall separately in order to form contact faces for contacting neighbouring chamber walls, and the step of connecting the separate wall parts by means of pin fasteners to form one unit, may be dispensed with. Furthermore, the main chamber element formed by said one single metal casting may be machined in one operation in order to form both contact faces for wear plates and contact faces for tie rod guide bushings. Thereby, an even better mutual alignment of all these contact faces may be obtained or at least the required accuracy may be obtained with less effort and therefore in a more cost efficient way.

[0011] In an embodiment, the chamber top wall includes as a part of the main chamber element a first funnel part forming a lower part of a sand feeding funnel leading into the at least one sand filling opening, and a second funnel part forming an upper part of the sand feeding funnel is attached to the first funnel part and is made from a separate metal casting. Thereby, said one single metal casting adapted to make up the main chamber element may be produced with an adequate distribution of the molten metal during the casting process. If, on the other hand, an entire sand filling funnel would have to form part of the main chamber element formed by said one single metal casting, the distribution of the molten metal during the casting process could be so uneven that for instance shrinkage defects and related problems could occur. Furthermore, by including the first funnel part in the main chamber element, good strength and precision may be obtained at the bottom of the sand filling funnel. Strength is necessary in particular at P3624PC00

[0012] 3

[0013] the bottom of the sand filling funnel, because large forces are involved during sand filling of the moulding chamber and in particular during compaction of sand in the moulding chamber, and high precision is also necessary at the bottom of the sand filling funnel in order to accurately control the position at which sand is filled into the moulding chamber through the sand filling opening.

[0014] In an embodiment, the sand feeding funnel is lined by means of a funnel insert, and the funnel insert is supported by the first funnel part against displacement in the longitudinal direction of the sand moulding chamber. Thereby, the first funnel part which is an integrated part of the main chamber element formed by said one single metal casting may provide the necessary precise support of a lower part of the funnel insert in the longitudinal direction of the sand moulding chamber. Thereby, the lower part of the funnel insert may accurately control the position at which sand is filled into the moulding chamber through the sand filling opening. An upper part of the funnel insert may be supported by the second funnel part being attached to the first funnel part. At the upper part of the sand filling funnel, precision requirements may be lower than at the lower part of the sand filling funnel.

[0015] In an embodiment, the funnel insert is provided with at least two support elements arranged on opposite outer sides of the funnel insert, respectively, each support element abuts a respective support surface arranged in the first funnel part and extending at least substantially in a longitudinal direction of the sand feeding funnel, and each support element is free to slide along said support surface at least substantially in the longitudinal direction of the sand feeding funnel. Thereby, the funnel insert may by means of the at least two support elements be supported by the first funnel part against displacement in the longitudinal direction of the sand moulding chamber. At the same time, the lower part of the funnel insert may be allowed some flexibility for movement up and down in vertical direction, that is, in the longitudinal direction of the sand feeding funnel. An upper end of the funnel insert may be attached to the upper end of the second funnel part which may thereby support the funnel insert in the longitudinal direction of the sand feeding funnel. P3624PC00

[0016] 4

[0017] The support surfaces arranged in the first funnel part may be machined in one machining operation of the main chamber element in which also the contact faces for wear plates and the contact faces for tie rod guide bushings are machined. Thereby, high accuracy and good production economy may be achieved.

[0018] In an embodiment, the external side of the sand moulding chamber forms at least one machined contact face for attachment and support of at least one compaction cylinder or piston of the compacting system. Thereby, said contact face for attachment and support of at least one compaction cylinder or piston may be machined in one machining operation of the main chamber element together with the contact faces for wear plates and the contact faces for tie rod guide bushings, whereby a high degree of accuracy may be achieved in the alignment between the compaction cylinder or piston and both the contact faces for wear plates and the contact faces for tie rod guide bushings. Consequently, it may be possible to arrange the compaction cylinder or piston on the external side of the sand moulding chamber without even performing adjustments of the position of the compaction cylinder or piston on the external side of the sand moulding chamber. Thereby, high accuracy and good production economy may be achieved. The compaction cylinder is preferably a hydraulic cylinder.

[0019] In an embodiment, each one of the two opposed chamber side walls forms at least one machined contact face for attachment and support of at least one compaction cylinder or piston of the compacting system. Thereby, as explained above, a high degree of accuracy in alignment may be achieved, and in this case also in the alignment between the respective compaction cylinders or pistons arranged on either side of the sand moulding chamber. The two opposed chamber side walls may support a first and a second compaction cylinder or piston for operation of a swing plate system of the sand moulding machine. The compaction cylinder is preferably a hydraulic cylinder.

[0020] In an embodiment, the sand moulding chamber includes a chamber rear wall adapted for attachment and support of at least one compaction cylinder or piston of the com- P3624PC00

[0021] 5

[0022] pacting system. Thereby, the chamber rear wall may support a central compaction cylinder or piston for operation of a pressing plate of the sand moulding machine. The compaction cylinder is preferably a hydraulic cylinder.

[0023] In an embodiment, the chamber rear wall is made from a separate metal casting.

[0024] Thereby, machining of said one single metal casting making up the main chamber element may be facilitated in that access to the internal cavity of said one single metal casting may be easier before mounting the chamber rear wall on the main chamber element.

[0025] In an embodiment, a rear end of the main chamber element formed by at least the chamber top wall, the chamber bottom wall, and the two opposed chamber side walls forms at least one machined contact face in abutment with at least one corresponding machined contact face of the chamber rear wall, and the chamber rear wall is connected to the main chamber element in such a way that the position of the chamber rear wall may be adjusted, during mounting of the chamber rear wall on the main chamber element, in relation to the main chamber element in at least two different directions being at right angles to the longitudinal direction of the sand moulding chamber. Thereby, a compaction cylinder or piston attached and supported on the chamber rear wall may be adjusted in relation to wear plates supported by the contact faces for wear plates on the chamber walls, whereby the adjustment may be performed by adjusting the position of the chamber rear wall in relation to the main chamber element.

[0026] In an embodiment, internal corners formed between the chamber top wall and each of the two opposed chamber side walls and formed between the chamber bottom wall and each of the two opposed chamber side walls have been machined to a rounded form. Thereby, an uneven stress distribution in the material of the internal corners formed between the chamber walls may be avoided. Such uneven stress distribution in the material could otherwise lead to a notch effect in such corners which could reduce the load capacity. P3624PC00

[0027] 6

[0028] In an embodiment, the rounded form of said internal corners has the form of an undercut. Thereby, by providing said internal corners in the form of an undercut, more space may be provided for the corners formed by the wear plates when these are mounted in the sand moulding chamber. Thereby, in turn, corners formed by the wear plates may not need to be chamfered or bevelled to such a high degree as could otherwise be required in order to avoid that the corners formed by the wear plates abut said internal corners. Consequently, as a result, the wear plates may be stronger at the corners formed thereby.

[0029] In an embodiment, the internal side of each of the chamber top wall, the chamber bottom wall, and the two opposed chamber side walls is lined with a respective wear plate, and at least one of two neighbouring wear plates meeting at a respective internal corner formed between said chamber walls is provided with a chamfer or bevel at an external edge of said wear plate. Thereby, the internal corners formed between the chamber walls may not need to be undercut to such a high degree that could otherwise be necessary in order to avoid that the corners of the wear plates abut said internal corners.

[0030] The present invention further relates to a vertical sand moulding machine including a sand moulding chamber as described above, wherein a first compaction cylinder for operation of a swing plate system is attached to and supported by the at least one machined contact face formed by a first one of the two opposed chamber side walls, wherein a second compaction cylinder for operation of the swing plate system is attached to and supported by the at least one machined contact face formed by a second one of the two opposed chamber side walls, and wherein a third compaction cylinder for operation of a pressing plate is attached to and supported by at least one machined contact face formed by the chamber rear wall.

[0031] The present invention further relates to a sand moulding chamber for a vertical sand moulding machine for the production of sand mould parts, wherein the sand moulding chamber includes at least a chamber top wall, a chamber bottom wall, and two opposed chamber side walls, wherein all said chamber walls extend in a longitudinal direction of the sand moulding chamber and all said chamber walls are formed of cast metal, P3624PC00

[0032] 7

[0033] wherein at least one of said chamber walls is provided with at least one sand filling opening, wherein the sand moulding chamber includes machined contact faces and nonmachined surfaces, wherein at least part of an internal side of each said chamber wall is provided with at least one machined contact face for attachment of a wear plate, wherein an external side of the sand moulding chamber forms a number of tie rod bearing extensions having bores for insertion of tie rod guide bushings for guiding, in the longitudinal direction of the sand moulding chamber, respective tie rods of a compacting system of the vertical sand moulding machine, and wherein each tie rod bearing extension includes at least one machined contact face for contacting the respective tie rod guide bushing. The sand moulding chamber is characterised in that at least the chamber top wall, the chamber bottom wall, and the two opposed chamber side walls together form a main chamber element made from one single metal casting, in that the chamber top wall includes as a part of the main chamber element a first funnel part forming a lower part of a sand feeding funnel leading into the at least one sand filling opening, in that a second funnel part forming an upper part of the sand feeding funnel is attached to the first funnel part and is made from a separate metal casting, in that the sand feeding funnel is lined by means of a funnel insert, in that the funnel insert is supported by the first funnel part against displacement in the longitudinal direction of the sand moulding chamber, and in that the second funnel part is only connected to the funnel insert at an upper flange of the second funnel part. Thereby, because the second funnel part is only connected to the funnel insert at an upper flange of the second funnel part, and because the funnel insert is supported by the first funnel part against displacement in the longitudinal direction of the sand moulding chamber, the second funnel part does not need to take up large forces necessary for supporting the funnel insert adequately against displacement, at the lower part of the funnel insert, in the longitudinal direction of the sand moulding chamber, and therefore material may be saved in that the second funnel part may be cast with weaker walls than the first funnel part. Therefore, the second funnel part forming an upper part of the sand feeding funnel may be cast with weaker walls than the first funnel part forming a lower part of the sand feeding funnel which may be done without any risk of shrinkage defects or the like, because the first funnel part and the second funnel part are made from separate metal castings. The funnel insert may typically be made of a relatively thinner material than that of the casted P3624PC00

[0034] 8

[0035] funnel parts, and therefore, the funnel insert may flex somewhat between the upper flange of the second funnel part and the second funnel part supporting the funnel insert in the longitudinal direction of the sand moulding chamber. As a result, the second funnel part does not need to take up large forces necessary for supporting the funnel insert adequately against displacement in the longitudinal direction of the sand moulding chamber.

[0036] The present invention further relates to a sand moulding chamber for a vertical sand moulding machine for the production of sand mould parts, wherein the sand moulding chamber includes at least a chamber top wall, a chamber bottom wall, and two opposed chamber side walls, wherein all said chamber walls extend in a longitudinal direction of the sand moulding chamber and all said chamber walls are formed of cast metal, wherein at least one of said chamber walls is provided with at least one sand filling opening, wherein the sand moulding chamber includes machined contact faces and nonmachined surfaces, wherein at least part of an internal side of each said chamber wall is provided with at least one machined contact face for attachment of a wear plate, wherein an external side of the sand moulding chamber forms a number of tie rod bearing extensions having bores for insertion of tie rod guide bushings for guiding, in the longitudinal direction of the sand moulding chamber, respective tie rods of a compacting system of the vertical sand moulding machine, and wherein each tie rod bearing extension includes at least one machined contact face for contacting the respective tie rod guide bushing. The sand moulding chamber is characterised in that at least the chamber top wall, the chamber bottom wall, and the two opposed chamber side walls together form a main chamber element made from one single metal casting, in that internal corners formed between the chamber top wall and each of the two opposed chamber side walls and formed between the chamber bottom wall and each of the two opposed chamber side walls have been machined to a rounded form, and in that, preferably, the rounded form of said internal corners has the form of an undercut. Thereby, an uneven stress concentration in the material of the internal corners formed between the chamber walls may be avoided. Such uneven stress distribution in the material could otherwise lead to a notch effect in such corners which could reduce the load capacity. By pos- P3624PC00

[0037] 9

[0038] sibly providing said internal corners in the form of an undercut, more space may be provided for the corners formed by the wear plates when these are mounted in the sand moulding chamber. Thereby, in turn, corners formed by the wear plates may not need to be chamfered or bevelled to such a high degree as could otherwise be required in order to avoid that the corners formed by the wear plates abut said internal corners. Consequently, as a result, the wear plates may be stronger at the corners formed thereby.

[0039] In an embodiment of the sand moulding chamber described just above, the internal side of each of the chamber top wall, the chamber bottom wall, and the two opposed chamber side walls is lined with a respective wear plate, and at least one of two neighbouring wear plates meeting at a respective internal corner formed between said chamber walls is provided with a chamfer or bevel at an external edge of said wear plate. Thereby, the above-mentioned features may be obtained.

[0040] The present invention further relates to a set of at least four wear plates for use in lining a sand moulding chamber as described just above, wherein at least one of two neighbouring wear plates meeting at a respective internal corner formed between said chamber walls is provided with a chamfer or bevel at an external edge of said wear plate. Thereby, the above-mentioned features may be obtained.

[0041] In some embodiments, one or more of the chamber top wall, the chamber bottom wall, and the two opposed chamber side walls may be lined with more than one wear plate, i.e. the respective chamber wall or walls may be lined by two or more wear plates arranged beside each other.

[0042] The present invention further relates to a set of at least four wear plates for use in lining a sand moulding chamber for a vertical sand moulding machine for the production of sand mould parts, wherein the sand moulding chamber includes at least a chamber top wall, a chamber bottom wall, and two opposed chamber side walls, wherein all said chamber walls extend in a longitudinal direction of the sand moulding chamber and all said chamber walls are formed of cast metal, wherein at least one of said chamber walls is provided with at least one sand filling opening, wherein the sand moulding chamber P3624PC00

[0043] 10

[0044] includes machined contact faces and non-machined surfaces, wherein at least part of an internal side of each said chamber wall is provided with at least one machined contact face for attachment of a wear plate. The set of at least four wear plates is characterised in that at least the chamber top wall, the chamber bottom wall, and the two opposed chamber side walls together form a main chamber element made from one single metal casting, in that internal corners formed between the chamber top wall and each of the two opposed chamber side walls and formed between the chamber bottom wall and each of the two opposed chamber side walls have been machined to a rounded form, and in that, preferably, the rounded form of said internal corners has the form of an undercut, wherein at least one of two neighbouring wear plates meeting at a respective internal corner formed between said chamber walls is provided with a chamfer or bevel at an external edge of said wear plate. Thereby, the above-mentioned features may be obtained.

[0045] The present invention further relates to a method of producing a sand moulding chamber for a vertical sand moulding machine for the production of sand mould parts, the sand moulding chamber including at least a chamber top wall, a chamber bottom wall, and two opposed chamber side walls, all said chamber walls extending in a longitudinal direction of the sand moulding chamber, wherein at least one of said chamber walls is provided with at least one sand filling opening, wherein an external side of the sand moulding chamber forms a number of tie rod bearing extensions having bores for insertion of tie rod guide bushings for guiding, in the longitudinal direction of the sand moulding chamber, tie rods of a compacting system of the vertical sand moulding machine, the method including the steps of forming in a metal casting process the chamber top wall, the chamber bottom wall, and the two opposed chamber side walls, subsequently machining on at least part of an internal side of each said chamber wall at least one contact face for attachment of a wear plate, and machining on each tie rod bearing extension at least one contact face for contacting the respective tie rod guide bushing.

[0046] The method is characterised by casting together at least the chamber top wall, the chamber bottom wall, and the two opposed chamber side walls as one single metal casting. Thereby, the above-mentioned features may be obtained. P3624PC00

[0047] 11

[0048] In an embodiment, the method includes installing said one single metal casting in a machining centre and subsequently machining, before deinstalling said one single metal casting from the machining centre, the at least one contact face for attachment of a wear plate and the at least one contact face for contacting the respective tie rod guide bushing. Thereby, the above-mentioned features may be obtained.

[0049] In an embodiment, the method includes the further step of, after installing said one single metal casting in the machining centre and before deinstalling said one single metal casting from the machining centre, machining on the external side of the sand moulding chamber at least one contact face for attachment of at least one compaction cylinder or piston of the compacting system. Thereby, the above-mentioned features may be obtained.

[0050] In an embodiment, the method includes the further step of machining to a rounded form internal corners formed between the chamber top wall and each of the two opposed chamber side walls and formed between the chamber bottom wall and each of the two opposed chamber side walls. Thereby, the above-mentioned features may be obtained.

[0051] In an embodiment, during the casting of said one single metal casting, the internal corners formed between the chamber top wall and each of the two opposed chamber side walls and formed between the chamber bottom wall and each of the two opposed chamber side walls are formed without an undercut, and, during the step of machining said internal corners to a rounded form, said rounded form is machined to form an undercut. Thereby, during machining, the geometry of the rounded form of the corner may be accurately controlled in relation to tensile stress in the material of the corner. The undercut may be designed to result in a minimum of tensions in the rounded corner. Forming the undercut corner during the process of casting could lead to problems, because a combination of high tolerances and a thin core could lead to breaking of the core. P3624PC00

[0052] 12

[0053] The present invention further relates to a method of producing a sand moulding chamber for a vertical sand moulding machine for the production of sand mould parts, the sand moulding chamber including at least a chamber top wall, a chamber bottom wall, and two opposed chamber side walls, all said chamber walls extending in a longitudinal direction of the sand moulding chamber, wherein at least one of said chamber walls is provided with at least one sand filling opening, wherein the sand moulding chamber includes machined contact faces and non-machined surfaces, wherein an external side of the sand moulding chamber forms a number of tie rod bearing extensions having bores for insertion of tie rod guide bushings for guiding, in the longitudinal direction of the sand moulding chamber, tie rods of a compacting system of the vertical sand moulding machine, the method including the steps of forming in a metal casting process the chamber top wall, the chamber bottom wall, and the two opposed chamber side walls, subsequently machining on at least part of an internal side of each said chamber wall at least one contact face for attachment of a wear plate, and machining on each tie rod bearing extension at least one contact face for contacting the respective tie rod guide bushing. The method is characterised by casting together at least the chamber top wall, the chamber bottom wall, and the two opposed chamber side walls as one single metal casting, installing said one single metal casting in a machining centre and subsequently machining, before deinstalling said one single metal casting from the machining centre, the at least one contact face for attachment of a wear plate and the at least one contact face for contacting the respective tie rod guide bushing, the method including the further step of machining to a rounded form internal corners formed between the chamber top wall and each of the two opposed chamber side walls and formed between the chamber bottom wall and each of the two opposed chamber side walls, and wherein, preferably, during the casting of said one single metal casting, the internal corners formed between the chamber top wall and each of the two opposed chamber side walls and formed between the chamber bottom wall and each of the two opposed chamber side walls are formed without an undercut, and wherein, during the step of machining said internal corners to a rounded form, said rounded form is machined to form an undercut. Thereby, the above-mentioned features may be obtained. P3624PC00

[0054] 13

[0055] In an embodiment, before installing said one single metal casting in the machining centre and subsequently machining the at least one contact face for attachment of a wear plate and the at least one contact face for contacting the respective tie rod guide bushing, as described above, said one single metal casting is installed in a machining centre and the bottom, the front, or the rear side thereof is machined to form a reference face for the machining described above of the at least one contact face for attachment of a wear plate and the at least one contact face for contacting the respective tie rod guide bushing.

[0056] In an embodiment of the method of producing a sand moulding chamber described just above, the method includes the further step of, after installing said one single metal casting in the machining centre and before deinstalling said one single metal casting from the machining centre, machining on the external side of the sand moulding chamber at least one contact face for attachment of at least one compaction cylinder or piston of the compacting system. Thereby, the above-mentioned features may be obtained.

[0057] The invention will now be explained in more detail below by means of examples of embodiments with reference to the very schematic drawing, in which

[0058] Fig. 1 is a perspective view of a prior art sand moulding chamber, before assembly of a chamber top wall, two chamber side wall and a chamber bottom wall;

[0059] Fig. 2 is a perspective view of a sand moulding chamber according to the present invention, in the form of one single metal casting, shown before machining of contact faces on the single metal casting, and a separate second funnel part, before attachment of the separate second funnel part to the single metal casting;

[0060] Fig. 3 is a perspective view of the sand moulding chamber of Fig. 2, shown after machining of contact faces on the single metal casting; P3624PC00

[0061] 14

[0062] Fig. 4 is a perspective view of the sand moulding chamber of Fig. 2, seen from another angle, and with a chamber rear wall before attachment of this on the single metal casting;

[0063] Fig. 5 is a perspective view corresponding to that of Fig. 4, however, whereby the separate second funnel part and the chamber rear wall has been attached to the single metal casting, and whereby a funnel insert has been attached into the funnel of the sand moulding chamber;

[0064] Fig. 6 is a top view of the sand moulding chamber of Fig. 3, however, without the separate second funnel part and with the chamber rear wall attached to the single metal casting;

[0065] Fig. 7 is a perspective view of the sand moulding chamber of Fig. 5, seen from another angle, and before attachment of the funnel insert into the funnel of the sand moulding chamber;

[0066] Fig. 8 is a cross-section in a longitudinal direction of the sand moulding chamber of part of the chamber of Fig. 5, however without the separate second funnel part attached to the single metal casting;

[0067] Fig. 9 is a cross-section corresponding to that of Fig. 8, however whereby the separate second funnel part has been attached to the single metal casting;

[0068] Fig. 10 is a perspective cross-sectional view of the sand moulding chamber of Fig. 5, seen from another angle, and taken along a plane being at right angles to the longitudinal direction of the sand moulding chamber;

[0069] Fig. 11 is a perspective longitudinal cross-sectional view of part of the sand moulding chamber of Fig. 5, seen from another angle;

[0070] Fig. 12 illustrates a detail of Fig. 11 on a larger scale; P3624PC00

[0071] 15

[0072] Fig. 13 illustrates a detail of Fig. 9 on a larger scale;

[0073] Fig. 14 is a perspective view of a sand moulding chamber according to the present invention together with wear plates and funnel insert, before installation of the wear plates and the funnel insert;

[0074] Fig. 15 is a perspective view corresponding to that of Fig. 14, however after installation of the wear plates and the funnel insert;

[0075] Fig. 16 is a cross-section of part of the sand moulding chamber of Fig. 15 taken along a plane at right angles to the longitudinal direction of the sand moulding chamber, and seen on a larger scale, whereby the wear plates have been illustrated as being transparent so that the air vent holes are visible;

[0076] Fig. 17 illustrates a detail of Fig. 16 on a larger scale, however without the wear plates being transparent and therefore without the air vent holes being visible;

[0077] Fig. 18 is an end view of the detail illustrated in Fig. 17, however before machining an internal corner and before attaching wear plates;

[0078] Fig. 19 is a cross-sectional view of a detail corresponding to that illustrated in Fig. 17, however after machining an internal corner and before attaching wear plates;

[0079] Fig. 20 is a perspective view of a procedure of machining an internal undercut rounded corner of a sand moulding chamber according to the present invention;

[0080] Fig. 21 is a perspective view of a sand moulding machine incorporating a sand moulding chamber according to the present invention; P3624PC00

[0081] 16

[0082] Fig. 22 is a perspective view of the sand moulding machine of Fig. 21, seen from a different angle, wherein the chamber rear wall is illustrated as being transparent, and without the side mounted cylinders and tie rods of the compacting system being illustrated;

[0083] Fig. 23 illustrates a detail of Fig. 22 on a larger scale; however, wherein the chamber rear wall is not transparent, and

[0084] Fig. 24 is a perspective view of the rear plate of the sand moulding machine of Fig. 22.

[0085] In the following, generally, similar elements of different embodiments have been designated by the same reference numerals.

[0086] Fig. 1 illustrates parts of a prior art sand moulding chamber 1 for a vertical sand moulding machine 2 before assembly of the parts. The prior art sand moulding chamber 1 is to be assembled from four separate castings forming the top wall 3, the two side walls 5, 6 and the bottom wall 4, respectively. Before assembling these separate castings, each casting has to be installed individually in a machining centre in order to machine an internal side 8 of the chamber wall to form a contact face for attachment of a not shown wear plate and in order to machine contact faces for contacting neighbouring chamber walls after assembly of these. Subsequently, the four chamber walls 3, 4, 5, 6 are screwed together, and the assembled chamber unit is installed in a machining centre, wherein the separate parts are further connected by means of pin fasteners to form one unit. This one unit is subsequently machined to form contact faces for contacting respective tie rod guide bushings. However, this procedure is work intensive and consequently costly.

[0087] Fig. 3 illustrates an embodiment of a sand moulding chamber 1 according to the present invention. The sand moulding chamber 1 is for use in a vertical sand moulding machine 2 as illustrated in Figs. 21 and 22 for the production of not shown sand mould parts. P3624PC00

[0088] 17

[0089] The type of vertical sand moulding machine 2 illustrated in Figs. 21 and 22 operates according to the vertical flaskless sand moulding technique such as the DISAMATIC (Registered Trademark) technique, according to which a first and a second vertical plate in the form of a pressing plate and a swing plate 72, respectively, each provided with a pattern plate, are arranged oppositely at either end of the sand moulding chamber 1, thereby forming movable end walls of the sand moulding chamber. During the moulding of a single mould part the patterns of the pattern plates are extending into each respective end of the sand moulding chamber 1. A slit-formed sand inlet opening, i.e. a sand filling opening 7, extending across a chamber wall is arranged typically at the top of the sand moulding chamber. Sand is blown in through the slit-formed opening and into the sand moulding chamber 1. Thereafter, by displacement of the first and / or the second plate, the plates move relatively in direction towards each other and squeeze the sand therebetween. After compaction of the sand in the sand moulding chamber, the swing plate 72 is retracted from the sand moulding chamber and swung away from the opening of the sand moulding chamber, thereby allowing passage of the sand mould part out from the sand moulding chamber by further displacement of the pressing plate in a well-known manner. The swing plate 72 is journalled on a front yoke which is in turn mounted on tie rods 18 for movement relative to the sand moulding chamber 1. After being removed from the sand moulding chamber, the sand mould part is placed adjacent the previously moulded sand mould part on a conveyer. Thereby, two neighbouring sand mould parts form a complete sand mould. The cavity formed by these two sand mould parts constitutes a cavity for the subsequent casting of the metal product. The pressing plate and the pattern plates are not visible in the figures illustrating the vertical sand moulding machine.

[0090] The sand moulding chamber 1 illustrated in Fig. 3 includes a chamber top wall 3, a chamber bottom wall 4, and two opposed chamber side walls 5, 6. All said chamber walls 3, 4, 5, 6 extend in a longitudinal direction L of the sand moulding chamber 1 and all said chamber walls 3, 4, 5, 6 are formed of cast metal. The chamber top wall 3 is provided with a sand filling opening 7 as illustrated in Figs. 8 and 9, and a part of an internal side 8 of each said chamber wall 3, 4, 5, 6 is provided with a machined contact face 9 for attachment of a wear plate 10, 11, 12, 13 as illustrated in Figs. 14 and 15. An external side P3624PC00

[0091] 18

[0092] 14 of the sand moulding chamber 1 forms a number of tie rod bearing extensions 15 having bores 16 for insertion of tie rod guide bushings 17 as also seen in Figs. 14 and 15. As seen in Fig. 21, the tie rod guide bushings 17 are adapted for guiding, in the longitudinal direction L of the sand moulding chamber 1, respective tie rods 18 of a compacting system 19 of the vertical sand moulding machine 2. As illustrated in Figs. 3 and 4, each tie rod bearing extension 15 includes a machined contact face 20 for contacting the respective tie rod guide bushing 17.

[0093] According to the present invention, at least the chamber top wall 3, the chamber bottom wall 4, and the two opposed chamber side walls 5, 6 together form one single main chamber element 21 as illustrated in Fig. 3. As understood, the main chamber element 21 is a coherent element formed by at least the chamber top wall 3, the chamber bottom wall 4, and the two opposed chamber side walls 5, 6 meaning that no separate connections are formed between the respective chamber walls 3, 4, 5, 6. The main chamber element 21 is made from one single metal casting 22 as illustrated in Fig. 2. In this way, the steps involved in the manufacture of the prior art sand moulding chamber 1 illustrated in Fig. 1 of machining each chamber wall 3, 4, 5, 6 separately in order to form contact faces for contacting neighbouring chamber walls, and the step of connecting the separate wall parts by means of pin fasteners to form one unit, have been dispensed with. Furthermore, the main chamber element 21 formed by the one single metal casting 22 may be machined in one operation in order to form both contact faces 9 for wear plates 10, 11, 12, 13 and contact faces 20 for tie rod guide bushings 17. Thereby, an even better mutual alignment of all these contact faces 9, 20 may be obtained or at least the required accuracy may be obtained with less effort and therefore in a more cost efficient way. In the same one operation of machining, for instance a lower side 74 of the chamber bottom wall 4 may also be machined in order to contact a not shown table on which the sand moulding chamber 1 is to be mounted by means of bolts.

[0094] In the embodiment illustrated in Figs. 3 to 13, the chamber top wall 3 includes as a part of the main chamber element 21 a first funnel part 25 forming a lower part of a sand feeding funnel 26 leading into the at least one sand filling opening 7. A second funnel P3624PC00

[0095] 19

[0096] part 27 forming an upper part of the sand feeding funnel 26 is attached to the first funnel part 25 and is made from a separate metal casting 28. Thereby, the one single metal casting 22 adapted to make up the main chamber element 21 may be produced with an adequate distribution of the molten metal during the casting process. If, on the other hand, an entire sand filling funnel would have to form part of the main chamber element 21 formed by the one single metal casting 22, the distribution of the molten metal during the casting process could be so uneven that for instance shrinkage defects and related problems could occur. Furthermore, by including the first funnel part 25 in the main chamber element 21, good strength and precision may be obtained at the bottom of the sand filling funnel 26. Strength is necessary in particular at the bottom of the sand filling funnel 26, because large forces are involved during sand filling of the sand moulding chamber 1 and in particular during compaction of sand in the moulding chamber, and high precision is also necessary at the bottom of the sand filling funnel 26 in order to accurately control the position at which sand is filled into the sand moulding chamber through the sand filling opening 7.

[0097] In the embodiment illustrated, the tie rod bearing extensions 15 at a front end of the main chamber element 21 are formed integrated with, i.e. directly connected with, the first funnel part 25 forming part of the main chamber element 21 and forming a lower part of the sand feeding funnel 26. Thereby, good strength of the main chamber element 21 may be obtained for adequate support of the tie rod bearing extensions 15 and the first funnel part 25.

[0098] In the embodiment illustrated, the second funnel part 27 is provided with a lower flange 47 adapted to be bolted onto an upper flange 48 of the first funnel part 25 in order to form the sand feeding funnel 26. However, the first funnel part 25 and the second funnel part 27 may be connected in any suitable way.

[0099] In the embodiment illustrated, as seen for instance in Fig. 4, a top side of the upper flange 48 of the first funnel part 25 is located at a top side of the tie rod bearing extensions 15 which are integrated with the first funnel part 25. P3624PC00

[0100] 20

[0101] In the embodiment illustrated in Figs. 7 to 13, the sand feeding funnel 26 is lined by means of a funnel insert 29, and the funnel insert 29 is supported by the first funnel part 25 against displacement in the longitudinal direction L of the sand moulding chamber 1 as indicated in Fig. 13. Thereby, the first funnel part 25 which is an integrated part of the main chamber element 21 formed by the one single metal casting 22 may provide the necessary precise support of a lower part of the funnel insert 29 in the longitudinal direction L of the sand moulding chamber 1. As particularly well illustrated in Fig. 13, the lower part of the funnel insert 29 should accurately fit the position at which sand is filled into the sand moulding chamber 1 through the sand filling opening 7. The sand filling opening 7 in the chamber top wall 3 is further narrowed by a sand filling opening 66 in the top wear plate 10 which is defined by edges 65 as indicated in Fig. 13. Therefore, the sand filling opening 66 in the top wear plate 10 define the exact position at which sand is filled into the sand moulding chamber 1 through the sand filling opening 7. Noting that the top wear plate 10 is illustrated as being transparent in Fig. 13, and also referring to Fig. 12, it is seen that lower inner edges 67 of the funnel insert 29 match, in the longitudinal direction L of the sand moulding chamber 1, the position of the respective edges 65 of the sand filling opening 66 in the top wear plate 10. In the embodiment illustrated in Fig. 13, the respective edges 65 of the sand filling opening 66 extend in a vertical direction; however, in other embodiments, in particular for larger size sand moulding machines, the respective edges 65 may extend at an oblique angle relative to the vertical. In such case, the lower part of the funnel insert 29 should accurately fit the position of the uppermost part of the sand filling opening 66 in the top wear plate 10.

[0102] An upper part of the funnel insert 29 may be supported by the second funnel part 27 being attached to the first funnel part 25. At the upper part of the sand filling funnel 26, precision requirements may be lower than at the lower part of the sand filling funnel.

[0103] As particularly well illustrated in the embodiment of Fig. 13, the funnel insert 29 is provided with at least two support elements 30 arranged on opposite outer sides 31 of the funnel insert 29, respectively. Each support element 30 abuts a respective support surface 32 arranged in the first funnel part 25 and extending at least substantially in a longitudinal direction I of the sand feeding funnel 26. Each support element 30 is free to slide P3624PC00

[0104] 21

[0105] along said support surface 32 at least substantially in the longitudinal direction I of the sand feeding funnel 26. In order to facilitate insertion of the funnel insert 29 into the first funnel part 25 during assembly of the sand moulding machine 1, a lower edge of each support element 30 is chamfered. As understood, the funnel insert 29 may by means of the at least two support elements 30 be supported by the first funnel part 25 against displacement in the longitudinal direction L of the sand moulding chamber 1. At the same time, the lower part of the funnel insert 29 may be allowed some flexibility for movement up and down in vertical direction, that is, in the longitudinal direction I of the sand feeding funnel 26. An upper end of the funnel insert 29 is attached to the upper end of the second funnel part 27 which thereby prevents the upper end of the funnel insert 29 from moving in the longitudinal direction I of the sand feeding funnel 26. In the embodiment illustrated, the second funnel part 27 is provided with an upper flange 49 onto which an upper flange 50 of the funnel insert 29 is bolted. However, an upper end of the funnel insert may may be connected to an upper end of the second funnel part 27 in any suitable way. As a result of a flexibility of the material of the funnel insert 29, when sand is filled into the sand feeding funnel 26, each support element 30, as explained above, may slide along the respective support surface 32 at least substantially in the longitudinal direction I of the sand feeding funnel 26. The support elements 30 may have the form of metal blocks welded onto the outer sides 31 of the funnel insert 29. As seen, each metal block may be provided with an outer face extending in parallel with the longitudinal direction I of the sand feeding funnel 26 and being in contact with a respective support surface 32 in the first funnel part 25. As seen, the support surface 32 may be formed in a recess in an inner side of the first funnel part 25. In the illustrated embodiment, on either side of the outer side 31 the funnel insert 29, as seen in a longitudinal cross-section of the sand moulding chamber 1 as that of Figs. 8 and 9, the funnel insert 29 is provided with two support elements 30 being mutually spaced in the longitudinal direction I of the sand feeding funnel 26. Correspondingly, either side of an inside of the first funnel part 25 is provided with two recesses being mutually spaced in the longitudinal direction I of the sand feeding funnel 26, in each of which recess a support surface 32 is formed. However, the funnel insert 29 may be provided with any suitable number of support elements 30. As seen in Fig. 7, the support elements 30 may have the P3624PC00

[0106] 22

[0107] form of straight rods arranged on a flat part of the funnel insert 29. The second funnel part 27 is only connected to the funnel insert 29 at its upper flange 49.

[0108] The support surfaces 32 arranged in the first funnel part 25 may be machined in one machining operation of the main chamber element 21 together with the contact faces 9 for wear plates 10, 11, 12, 13 and the contact faces 20 for tie rod guide bushings 17.

[0109] Thereby, high accuracy and good production economy may be achieved.

[0110] In the embodiment illustrated, the external side 14 of the sand moulding chamber 1 forms machined contact faces 33, 34, 35, 41 for attachment and support of compaction cylinders 36, 38 in the form of hydraulic cylinders. Alternatively, the external side 14 of the sand moulding chamber 1 could form machined contact faces 33, 34, 35, 41 for attachment and support of pistons or piston rods of the compacting system 19. The contact faces 33, 34, 41 for attachment and support of left and right compaction cylinders 36 may be machined in one machining operation of the main chamber element 21 together with the contact faces 9 for wear plates 10, 11, 12, 13 and the contact faces 20 for tie rod guide bushings 17, whereby a high degree of accuracy may be achieved in the alignment between the compaction cylinders 36 and both the contact faces 9 for wear plates and the contact faces 20 for tie rod guide bushings 17. Consequently, it may be possible to arrange the compaction cylinders on the external side 14 of the sand moulding chamber 1 without even performing adjustments of the position of the compaction cylinder on the external side of the sand moulding chamber. Thereby, high accuracy and good production economy may be achieved.

[0111] In the embodiment illustrated, as seen in Figs. 3 to 6, each one of the two opposed chamber side walls 5, 6 forms two machined contact faces 33, 34 being mutually spaced in the longitudinal direction L of the sand moulding chamber 1. Each pair of mutually spaced machined contact faces 33, 34 is arranged for attachment and support of a respective compaction cylinder 36 of the compacting system 19 as illustrated in Fig. 21. Furthermore, each one of the two opposed chamber side walls 5, 6 forms part of a rear end 40 of the main chamber element 21 which forms a machined contact face 41 which may also serve for attachment and support of the respective left and right compaction P3624PC00

[0112] 23

[0113] cylinders 36 of the compacting system 19. Thereby, as explained above, a high degree of accuracy in alignment may be achieved, and in particular also in the mutual alignment between the respective compaction cylinders 36 arranged on either side of the sand moulding chamber 1 and the alignment between the respective compaction cylinders 36 and the tie rods 18. Accuracy of this alignment is necessary in order for the tie rods 18 and the pistons of the compaction cylinders 36 for the swing plate system 46 to move in parallel. The left and right compaction cylinders 36 form part of a swing plate system 46 of the vertical sand moulding machine 2 as illustrated in Fig. 21. The swing plate system 46 is adapted to operate in a manner known perse in order to open and close a swing plate 72 of the vertical sand moulding machine 2.

[0114] In the embodiment illustrated in Figs. 4 to 6, the sand moulding chamber 1 includes a chamber rear wall 39 adapted for attachment and support of a central compaction cylinder 38 of the compacting system 19. Thereby, the chamber rear wall 39 may support the central compaction cylinder 38 for operation of a not shown pressing plate of the vertical sand moulding machine 2. Preferably, the chamber rear wall 39 is adapted to take up at least substantially the entire compaction pressure from the central compaction cylinder 38. As seen in Fig. 24, an inside of the chamber rear wall 39 is provided with a star-formed arrangement of supporting ribs 53 extending from a bore 54 arranged centrally in the chamber rear wall 39. A not shown piston rod of the central compaction cylinder 38 extends through the bore 54 when the compaction cylinder 38 is mounted on the chamber rear plate 39 as seen in Figs. 21 and 22. The supporting ribs 53 enable the chamber rear wall 39 to take up at least substantially the entire compaction pressure from the central compaction cylinder 38 during operation of the sand moulding machine 2. The star-formed arrangement of supporting ribs 53 could have any other suitable configuration than the illustrated star-form and it could alternatively be provided at an outside of the chamber rear wall 39. Furthermore, the chamber rear wall 39 may be adapted to take up at least substantially the entire compaction pressure from the central compaction cylinder 38 without being provided with the illustrated supporting ribs 53, for instance by having a relatively larger wall thickness, or for instance by being provided with any other suitable kind of support structure. P3624PC00

[0115] 24

[0116] In the embodiment illustrated, the chamber rear wall 39 is made from a separate metal casting. Thereby, machining of the one single metal casting 22 making up the main chamber element 21 may be facilitated in that access to the internal cavity of the one single metal casting 22 may be easier before mounting the chamber rear wall 39 on the main chamber element 21. Alternatively, the chamber rear wall 39 may form part of the main chamber element 21 which is made from one single metal casting 22.

[0117] In the embodiment illustrated in Fig. 4, a rear end 40 of the main chamber element 21 formed by at least the chamber top wall 3, the chamber bottom wall 4, and the two opposed chamber side walls 5, 6 forms a machined contact face 41 in abutment with a corresponding machined contact face 42 of the chamber rear wall 39. The chamber rear wall 39 is connected to the main chamber element 21 in such a way that the position of the chamber rear wall 39 may be adjusted, during mounting of the chamber rear wall 39 on the main chamber element 21, in relation to the main chamber element 21 in at least two different directions being at right angles to the longitudinal direction L of the sand moulding chamber 1. Thereby, the central compaction cylinder 38 attached and supported on the chamber rear wall 39 may be adjusted in relation to the wear plates 10, 11, 12, 13 supported by the contact faces 9 for wear plates on the chamber walls 3, 4, 5, 6, whereby the adjustment may be performed by adjusting the position of the chamber rear wall in relation to the main chamber element.

[0118] In the illustrated embodiment, the chamber rear wall 39 is attached to the rear end 40 of the main chamber element 21 by means of a number of bolts 57 inserted through respective bores 55 of the chamber rear wall 39 and screwed into threaded holes 56 of the rear end 40. The bores 55 are distributed evenly along a periphery of the chamber rear wall 39. The adjustment of the position of the chamber rear wall 39 is possible in that the bores 55 of the chamber rear wall 39 have a slightly larger diameter than the outer diameter of the bolts 57. The adjustment may be performed in relation to a left stop block 58 and a lower left stop block 59 fixed to the main chamber element 21 as seen in Fig. 23. The left stop block 58 is attached to the left chamber side wall 5 and defines an outermost position to the left side of a left edge 61 of the chamber rear wall 39 when P3624PC00

[0119] 25

[0120] the left edge 61 of the chamber rear wall 39 abuts the left stop block 58. In order to adjust a horizontal position of the chamber rear wall 39 in a lateral direction the sand moulding chamber 1, a suitable number of not shown shims may be arranged in abutment between the left stop block 58 and the left edge 61 of the chamber rear wall 39 before final tightening of the bolts 57. A not visible, lower right stop block corresponding to the lower left stop block 59 is also provided. A not shown right stop block similar to the left stop block 58 may be provided, if necessary. Similarly, the lower stop block 59 is attached to the chamber bottom wall 4 and defines an outermost position to the lower side of a lower edge 62 of the chamber rear wall 39 when the lower edge 62 of the chamber rear wall 39 abuts the lower stop block 59. In order to adjust a vertical position of the chamber rear wall 39, a suitable number of not shown shims may be arranged in abutment between the lower stop block 59 and the lower edge 62 of the chamber rear wall 39 before final tightening of the bolts 57.

[0121] In order to further perform an accurate alignment of the central compaction cylinder 38 in relation to the wear plates 10, 11, 12, 13 supported by the contact faces 9 for wear plates on the chamber walls 3, 4, 5, 6, a vertical and / or horizontal adjustment may be performed of a back end 63 of the central compaction cylinder 38 in relation to the not shown table on which the sand moulding chamber 1 is mounted. The back end 63 of the central compaction cylinder 38 is supported on said not shown table by means of a cylinder bench 64 incorporating adjustment possibilities in vertical and horizontal direction as indicated by means of arrows in Fig. 22.

[0122] In the illustrated embodiment, as seen in Figs. 16 to 19, internal corners 43 formed between the chamber top wall 3 and each of the two opposed chamber side walls 5, 6 and formed between the chamber bottom wall 4 and each of the two opposed chamber side walls 5, 6 have been machined to a rounded form. Thereby, an uneven stress distribution in the material of the internal corners 43 formed between the chamber walls may be avoided. Such uneven stress distribution in the material could otherwise lead to a notch effect in such corners which could reduce the load capacity. P3624PC00

[0123] 26

[0124] Furthermore, in the illustrated embodiment, the rounded form of said internal corners 43 has the form of an undercut 44. Thereby, more space is provided for the corners formed by the wear plates 10, 11, 12, 13 when these are mounted in the sand moulding chamber 1. Thereby, in turn, corners formed by the wear plates may not need to be chamfered or bevelled to such a high degree as could otherwise be required in order to avoid that the corners formed by the wear plates abut said internal corners 43. Consequently, as a result, the wear plates may be stronger at the corners formed thereby. It is noted that if the corners formed by the wear plates would abut said internal corners 43, this could lead to a notch effect in the material of the corner.

[0125] Fig. 20 illustrates how the rounded form of said internal corners 43 may be machined to form an undercut 44 by means of a ball end mill 70 arranged on a displaceable arm 71. The ball end mill 70 rotates about a rotation axis R arranged at an angle of for example 45 degrees to both of the chamber walls 3, 6 meeting at the internal corner 43 and at right angles to the longitudinal direction L of the sand moulding chamber 1. During machining with the ball end mill 70, the displaceable arm 71 is displaced along a displacement axis D being parallel with the longitudinal direction L of the sand moulding chamber 1.

[0126] Furthermore, in the illustrated embodiment, in which the internal side 8 of each of the chamber top wall 3, the chamber bottom wall 4, and the two opposed chamber side walls 5, 6 is lined with a respective wear plate 10, 11, 12, 13, one of each pair of neighbouring wear plates meeting at the respective internal corners 43 formed between said chamber walls is provided with a chamfer 45 at an external edge of said wear plate at said internal corner 43, as illustrated in Fig. 17. As seen in Fig. 16, in fact the top wear plate 10 is provided with a chamfer 45 at either one of its left and right sides. Of course, alternatively, at those internal corners 43 formed at the top left and right sides, the left and right wear plates 12, 13 could be provided with a chamfer 45, or a chamber 45 could be formed on the left wear plate 12 and on the right side of the top wear plate 10, or a chamber 45 could be formed on the right wear plate 13 and on the left side of the top wear plate 10. Furthermore, wear plates meeting at an internal corner 43 could be P3624PC00

[0127] 1

[0128] joined by a mitre joint in which case a chamfer 45 could be provided to the joint by bevelling edges of both meeting wear plates. However, it is preferred that wear plates are joined at the internal corners 43 by abutting an end of one of the two wear plates to an internal side of the other one of the two wear plates, because this is less work intensive and provides an accurate internal corner 68 of the wear plates. This embodiment is seen in Fig. 17 in which it is also illustrated that the wear plates 10, 11, 12, 13 are attached to the respective chamber walls 3, 4, 5, 6 by means of bolts 69 inserted from an outside of the chamber walls and threaded into an outer side of the wear plates. It is noted that in the illustrated embodiments, the chamfer 45 forms an angle of approximately 45 degrees to each of the wear plates meeting at the respective internal corner 43. However, the chamfer 45 may form any suitable angle to each of the wear plates.

[0129] Figs. 21 and 22 illustrate a vertical sand moulding machine 2 including a sand moulding chamber 1 as described above, wherein a first compaction cylinder 36 for operation of a swing plate system 46 is attached to and supported by the three machined contact faces 33, 41 formed by the first one 5 of the two opposed chamber side walls 5, 6 as seen in Fig. 3. A second not visible compaction cylinder for operation of the swing plate system 46 is attached to and supported by the two machined contact faces 34 formed by the second one 6 of the two opposed chamber side walls 5, 6 as indicated in Fig. 6. Furthermore, a central compaction cylinder 38 for operation of a pressing plate is attached to and supported by the machined contact face 35 formed by the chamber rear wall 39 as seen in Figs. 4 and 5. In the illustrated embodiment, the machined contact face 35 is formed as a recess in a central bore in the chamber rear wall 39. The machined contact face 35 is provided with a number of bores for bolts attaching a front end of the central compaction cylinder 38 to the chamber rear wall 39. The swing plate system 46 and the pressing plate of the vertical sand moulding machine 2 are of a type well known in the art.

[0130] In a typical embodiment of the present invention, functional surfaces, i.e. those surfaces of the casted sand moulding chamber 1 which serve for mechanical contact with, attachment to, or support of other elements, are machined, i.e. subjected to material-removing operations such as milling or grinding, to provide the required dimensional precision P3624PC00

[0131] 28

[0132] and surface finish, and those surfaces are denoted machined contact faces. The remaining surfaces of the casted sand moulding chamber 1 may be left in their non-machined state, i.e. with the geometry defined by the casting mould, optionally cleaned, for example by shot blasting or sand blasting. Of course, some faces of the casted sand moulding chamber 1 may also be machined for other purposes than for being contact faces, as for instance the above discussed internal corners 43 formed between the chamber top wall 3 and each of the two opposed chamber side walls 5, 6 and formed between the chamber bottom wall 4 and each of the two opposed chamber side walls 5, 6 which have been machined to a rounded form. In this case, as explained, machining has been performed to avoid an uneven stress distribution in the material of the internal corners 43 formed between the chamber walls.

[0133] In a method of producing a sand moulding chamber 1 as described above according to the present invention, the method includes the steps of forming in a metal casting process the chamber top wall 3, the chamber bottom wall 4, and the two opposed chamber side walls 5, 6, subsequently machining on at least part of an internal side 8 of each said chamber wall 3, 4, 5, 6 at least one contact face 9 for attachment of a wear plate 10, 11, 12, 13, and machining on each tie rod bearing extension 15 at least one contact face 20 for contacting the respective tie rod guide bushing 17. The method is characterised by casting together at least the chamber top wall 3, the chamber bottom wall 4, and the two opposed chamber side walls 5, 6 as one single metal casting 22.

[0134] In an embodiment, the method includes installing said one single metal casting 22 in a machining centre and subsequently machining, before deinstalling said one single metal casting 22 from the machining centre, the at least one contact face 9 for attachment of a wear plate 10, 11, 12, 13 and the at least one contact face 20 for contacting the respective tie rod guide bushing 17.

[0135] In an embodiment, the method includes the further step of, after installing said one single metal casting 22 in the machining centre and before deinstalling said one single metal casting 22 from the machining centre, machining on the external side 14 of the P3624PC00

[0136] 29

[0137] sand moulding chamber 1 at least one contact face 33, 34, 35, 41 for attachment of at least one compaction cylinder 36, 38 or piston of the compacting system 19.

[0138] In an embodiment, the method includes the further step of machining to a rounded form internal corners 43 formed between the chamber top wall 3 and each of the two opposed chamber side walls 5, 6 and formed between the chamber bottom wall 4 and each of the two opposed chamber side walls 5, 6.

[0139] In an embodiment, during the casting of said one single metal casting 22, the internal corners 43 formed between the chamber top wall 3 and each of the two opposed chamber side walls 5, 6 and formed between the chamber bottom wall 4 and each of the two opposed chamber side walls 5, 6 are formed without an undercut 44, and, during the step of machining said internal corners 43 to a rounded form, said rounded form is machined to form an undercut 44. Thereby, during machining, the geometry of the rounded form of the corner 43 may be accurately controlled in relation to tensions in the material of the corner. The undercut 44 may be designed to result in a minimum of tensions in the rounded corner. Forming the undercut corner during the process of casting could lead to problems, because a combination of high tolerances and a thin core could lead to breaking of the core.

[0140] The following embodiments are disclosed:

[0141] Embodiment 1: A sand moulding chamber 1 for a vertical sand moulding machine 2 for the production of sand mould parts, wherein the sand moulding chamber 1 includes at least a chamber top wall 3, a chamber bottom wall 4, and two opposed chamber side walls 5, 6, wherein all said chamber walls 3, 4, 5, 6 extend in a longitudinal direction L of the sand moulding chamber 1 and all said chamber walls 3, 4, 5, 6 are formed of cast metal, wherein at least one of said chamber walls 3, 4, 5, 6 is provided with at least one sand filling opening 7, wherein the sand moulding chamber 1 includes machined contact faces and non-machined surfaces, wherein at least part of an internal side 8 of each said chamber wall 3, 4, 5, 6 is provided with at least one machined contact face 9 for attachment of a wear plate 10, 11, 12, 13, wherein an external side 14 of the sand moulding P3624PC00

[0142] 30

[0143] chamber 1 forms a number of tie rod bearing extensions 15 having bores 16 for insertion of tie rod guide bushings 17 for guiding, in the longitudinal direction L of the sand moulding chamber 1, respective tie rods 18 of a compacting system 19 of the vertical sand moulding machine 2, and wherein each tie rod bearing extension 15 includes at least one machined contact face 20 for contacting the respective tie rod guide bushing 17, characterised in that at least the chamber top wall 3, the chamber bottom wall 4, and the two opposed chamber side walls 5, 6 together form a main chamber element 21 made from one single metal casting 22.

[0144] Embodiment 2: A sand moulding chamber according to embodiment 1, wherein the chamber top wall 3 includes as a part of the main chamber element 21 a first funnel part 25 forming a lower part of a sand feeding funnel 26 leading into the at least one sand filling opening 7, and wherein a second funnel part 27 forming an upper part of the sand feeding funnel 26 is attached to the first funnel part 25 and is made from a separate metal casting 28.

[0145] Embodiment 3: A sand moulding chamber according to embodiment 2, wherein the sand feeding funnel 26 is lined by means of a funnel insert 29, and wherein the funnel insert 29 is supported by the first funnel part 25 against displacement in the longitudinal direction L of the sand moulding chamber 1.

[0146] Embodiment 4: A sand moulding chamber according to embodiment 3, wherein the funnel insert 29 is provided with at least two support elements 30 arranged on opposite outer sides 31 of the funnel insert 29, respectively, wherein each support element 30 abuts a respective support surface 32 arranged in the first funnel part 25 and extending at least substantially in a longitudinal direction I of the sand feeding funnel 26, and wherein each support element 30 is free to slide along said support surface 32 at least substantially in the longitudinal direction I of the sand feeding funnel 26.

[0147] Embodiment 5: A sand moulding chamber according to any one of the preceding embodiments, wherein the external side 14 of the sand moulding chamber 1 forms at least P3624PC00

[0148] 31

[0149] one machined contact face 33, 34, 35, 41 for attachment and support of at least one compaction cylinder 36, 38 or piston of the compacting system 19.

[0150] Embodiment 6: A sand moulding chamber according to any one of the preceding embodiments, wherein each one of the two opposed chamber side walls 5, 6 forms at least one machined contact face 33, 34, 41 for attachment and support of at least one compaction cylinder 36 or piston of the compacting system 19.

[0151] Embodiment 7: A sand moulding chamber according to any one of the preceding embodiments, wherein the sand moulding chamber 1 includes a chamber rear wall 39 adapted for attachment and support of at least one compaction cylinder 38 or piston of the compacting system 19.

[0152] Embodiment 8: A sand moulding chamber according to embodiment 7, wherein the chamber rear wall 39 is made from a separate metal casting.

[0153] Embodiment 9: A sand moulding chamber according to embodiment 8, wherein a rear end 40 of the main chamber element 21 formed by at least the chamber top wall 3, the chamber bottom wall 4, and the two opposed chamber side walls 5, 6 forms at least one machined contact face 41 in abutment with at least one corresponding machined contact face 42 of the chamber rear wall 39, and wherein the chamber rear wall 39 is connected to the main chamber element 21 in such a way that the position of the chamber rear wall 39 may be adjusted, during mounting of the chamber rear wall 39 on the main chamber element 21, in relation to the main chamber element 21 in at least two different directions being at right angles to the longitudinal direction L of the sand moulding chamber 1.

[0154] Embodiment 10: A sand moulding chamber according to any one of the preceding embodiments, wherein internal corners 43 formed between the chamber top wall 3 and each of the two opposed chamber side walls 5, 6 and formed between the chamber bottom wall 4 and each of the two opposed chamber side walls 5, 6 have been machined to a rounded form. P3624PC00

[0155] 32

[0156] Embodiment 11: A sand moulding chamber according to embodiment 10, wherein the rounded form of said internal corners 43 has the form of an undercut 44.

[0157] Embodiment 12: A sand moulding chamber according to embodiment 10 or 11, wherein the internal side 8 of each of the chamber top wall 3, the chamber bottom wall 4, and the two opposed chamber side walls 5, 6 is lined with a respective wear plate 10, 11, 12, 13, and wherein at least one of two neighbouring wear plates meeting at a respective internal corner 43 formed between said chamber walls is provided with a chamfer 45 or bevel at an external edge of said wear plate.

[0158] Embodiment 13: A vertical sand moulding machine 2 including a sand moulding chamber 1 according to embodiment 6 and 7, wherein a first compaction cylinder 36 for operation of a swing plate system 46 is attached to and supported by the at least one machined contact face 33, 41 formed by a first one 5 of the two opposed chamber side walls 5, 6, wherein a second compaction cylinder for operation of the swing plate system 46 is attached to and supported by the at least one machined contact face 34, 41 formed by a second one 6 of the two opposed chamber side walls 5, 6, and wherein a third compaction cylinder 38 for operation of a pressing plate is attached to and supported by at least one machined contact face 35 formed by the chamber rear wall 39.

[0159] Embodiment 14: A method of producing a sand moulding chamber 1 for a vertical sand moulding machine 2 for the production of sand mould parts, the sand moulding chamber 1 including at least a chamber top wall 3, a chamber bottom wall 4, and two opposed chamber side walls 5, 6, all said chamber walls 3, 4, 5, 6 extending in a longitudinal direction L of the sand moulding chamber 1, wherein at least one of said chamber walls 3, 4, 5, 6 is provided with at least one sand filling opening 7, wherein an external side 14 of the sand moulding chamber 1 forms a number of tie rod bearing extensions 15 having bores 16 for insertion of tie rod guide bushings 17 for guiding, in the longitudinal direction L of the sand moulding chamber 1, tie rods 18 of a compacting system 19 of the vertical sand moulding machine 2, the method including the steps of forming in a metal casting process the chamber top wall 3, the chamber bottom wall 4, and the two P3624PC00

[0160] 33

[0161] opposed chamber side walls 5, 6, subsequently machining on at least part of an internal side 8 of each said chamber wall 3, 4, 5, 6 at least one contact face 9 for attachment of a wear plate 10, 11, 12, 13, and machining on each tie rod bearing extension 15 at least one contact face 20 for contacting the respective tie rod guide bushing 17, characterised by casting together at least the chamber top wall 3, the chamber bottom wall 4, and the two opposed chamber side walls 5, 6 as one single metal casting 22.

[0162] Embodiment 15: A method of producing a sand moulding chamber according to embodiment 14, wherein the method includes installing said one single metal casting 22 in a machining centre and subsequently machining, before deinstalling said one single metal casting 22 from the machining centre, the at least one contact face 9 for attachment of a wear plate 10, 11, 12, 13 and the at least one contact face 20 for contacting the respective tie rod guide bushing 17.

[0163] Embodiment 16: A method of producing a sand moulding chamber according to embodiment 15, wherein the method includes the further step of, after installing said one single metal casting 22 in the machining centre and before deinstalling said one single metal casting 22 from the machining centre, machining on the external side 14 of the sand moulding chamber 1 at least one contact face 33, 34, 35, 41 for attachment of at least one compaction cylinder 36, 38 or piston of the compacting system 19.

[0164] Embodiment 17: A method of producing a sand moulding chamber according to embodiment 15 or 16, wherein the method includes the further step of machining to a rounded form internal corners 43 formed between the chamber top wall 3 and each of the two opposed chamber side walls 5, 6 and formed between the chamber bottom wall 4 and each of the two opposed chamber side walls 5, 6.

[0165] Embodiment 18: A method of producing a sand moulding chamber according to embodiment 17, wherein, during the casting of said one single metal casting 22, the internal corners 43 formed between the chamber top wall 3 and each of the two opposed chamber side walls 5, 6 and formed between the chamber bottom wall 4 and each of the two P3624PC00

[0166] 34

[0167] opposed chamber side walls 5, 6 are formed without an undercut 44, and wherein, during the step of machining said internal corners 43 to a rounded form, said rounded form is machined to form an undercut 44. P3624PC00

[0168] 35

[0169] List of reference numbers

[0170] D displacement axis of displaceable arm of machining centre L longitudinal direction of sand moulding chamber I longitudinal direction of sand feeding funnel

[0171] R rotation axis of ball end mill

[0172] 1 sand moulding chamber

[0173] 2 vertical sand moulding machine

[0174] 3 chamber top wall

[0175] 4 chamber bottom wall

[0176] 5 left chamber side wall

[0177] 6 right chamber side wall

[0178] 7 sand filling opening

[0179] 8 internal side of said chamber wall

[0180] 9 machined contact face for attachment of wear plate 10 top wear plate

[0181] 11 bottom wear plate

[0182] 12 left wear plate

[0183] 13 right wear plate

[0184] 14 external side of sand moulding chamber

[0185] 15 tie rod bearing extension

[0186] 16 bore of tie rod bearing extension

[0187] 17 tie rod guide bushing

[0188] 18 tie rod

[0189] 19 compacting system

[0190] 20 machined contact face for tie rod guide bushing

[0191] 21 main chamber element

[0192] 22 one single metal casting

[0193] 23 base plate of sand moulding chamber

[0194] 24 rear yoke connecting tie rods and piston rods

[0195] 25 first funnel part of sand feeding funnel

[0196] 26 sand feeding funnel P3624PC00

[0197] 27 second funnel part of sand feeding funnel

[0198] 28 separate metal casting making up second funnel part 29 funnel insert

[0199] 30 support element of funnel insert

[0200] 31 outer side of funnel insert

[0201] 32 support surface in first funnel part

[0202] 33 machined contact face for left compaction cylinder

[0203] 34 machined contact face for right compaction cylinder 35 machined contact face for central compaction cylinder 36 (first) left compaction cylinder

[0204] 37 left piston rod

[0205] 38 (third) central compaction cylinder

[0206] 39 chamber rear wall

[0207] 40 rear end of main chamber element

[0208] 41 machined contact face of rear end of main chamber element 42 machined contact face of chamber rear wall

[0209] 43 internal corner between chamber walls

[0210] 44 undercut

[0211] 45 chamfer at external edge of wear plate

[0212] 46 swing plate system

[0213] 47 lower flange of second funnel part

[0214] 48 upper flange of first funnel part

[0215] 49 upper flange of second funnel part

[0216] 50 upper flange of funnel insert

[0217] 51 support flange of first funnel part

[0218] 52 support flange of second funnel part

[0219] 53 supporting rib of chamber rear wall

[0220] 54 central bore in chamber rear wall

[0221] 55 bore of chamber rear wall

[0222] 56 threaded hole of rear end of main chamber element 57 bolt

[0223] 58 left stop block for chamber rear wall P3624PC00

[0224] 37

[0225] 59 lower left stop block for chamber rear wall 60 air vent hole of wear plate

[0226] 61 left edge of chamber rear wall

[0227] 62 lower edge of chamber rear wall

[0228] 63 back end of central compaction cylinder

[0229] 64 cylinder bench

[0230] 65 edge of sand filling opening in top wear plate 66 sand filling opening in top wear plate

[0231] 67 lower inner edges of funnel insert

[0232] 68 internal corner of wear plates

[0233] 69 bolt for wear plate

[0234] 70 ball end mill

[0235] 71 displaceable arm

[0236] 72 swing plate

[0237] 73 front yoke

[0238] 74 lower side of chamber bottom wall

[0239] 75 bolt for mounting chamber bottom wall on table 76 swing plate linkage mechanism

Claims

P3624PC0038Claims1. A sand moulding chamber (1) for a vertical sand moulding machine (2) for the production of sand mould parts, wherein the sand moulding chamber (1) includes at least a chamber top wall (3), a chamber bottom wall (4), and two opposed chamber side walls (5, 6), wherein all said chamber walls (3, 4, 5, 6) extend in a longitudinal direction (L) of the sand moulding chamber (1) and all said chamber walls (3, 4, 5, 6) are formed of cast metal, wherein at least one of said chamber walls (3, 4, 5, 6) is provided with at least one sand filling opening (7), wherein the sand moulding chamber (1) includes machined contact faces and non-machined surfaces, wherein at least part of an internal side (8) of each said chamber wall (3, 4, 5, 6) is provided with at least one machined contact face (9) for attachment of a wear plate (10, 11, 12, 13), wherein an external side (14) of the sand moulding chamber (1) forms a number of tie rod bearing extensions (15) having bores (16) for insertion of tie rod guide bushings (17) for guiding, in the longitudinal direction (L) of the sand moulding chamber (1), respective tie rods (18) of a compacting system (19) of the vertical sand moulding machine (2), and wherein each tie rod bearing extension (15) includes at least one machined contact face (20) for contacting the respective tie rod guide bushing (17), characterised in that at least the chamber top wall (3), the chamber bottom wall (4), and the two opposed chamber side walls (5, 6) together form a main chamber element (21) made from one single metal casting (22), in that the chamber top wall (3) includes as a part of the main chamber element (21) a first funnel part (25) forming a lower part of a sand feeding funnel (26) leading into the at least one sand filling opening (7), in that a second funnel part (27) forming an upper part of the sand feeding funnel (26) is attached to the first funnel part (25) and is made from a separate metal casting (28), in that the sand feeding funnel (26) is lined by means of a funnel insert (29), in that the funnel insert (29) is supported by the first funnel part (25) against displacement in the longitudinal direction (L) of the sand moulding chamber (1), and in that the second funnel part (27) is only connected to the funnel insert (29) at an upper flange (49) of the second funnel part (27).

2. A sand moulding chamber according to claim 1, wherein the funnel insert (29) is provided with at least two support elements (30) arranged on opposite outer sides (31) ofP3624PC0039the funnel insert (29), respectively, wherein each support element (30) abuts a respective support surface (32) arranged in the first funnel part (25) and extending at least substantially in a longitudinal direction (I) of the sand feeding funnel (26), and wherein each support element (30) is free to slide along said support surface (32) at least substantially in the longitudinal direction (I) of the sand feeding funnel (26).

3. A sand moulding chamber according to any one of the preceding claims, wherein the external side (14) of the sand moulding chamber (1) forms at least one machined contact face (33, 34, 35, 41) for attachment and support of at least one compaction cylinder (36, 38) or piston of the compacting system (19).

4. A sand moulding chamber according to any one of the preceding claims, wherein each one of the two opposed chamber side walls (5, 6) forms at least one machined contact face (33, 34, 41) for attachment and support of at least one compaction cylinder (36) or piston of the compacting system (19).

5. A sand moulding chamber according to any one of the preceding claims, wherein the sand moulding chamber (1) includes a chamber rear wall (39) adapted for attachment and support of at least one compaction cylinder (38) or piston of the compacting system (19).

6. A sand moulding chamber according to claim 5, wherein the chamber rear wall (39) is made from a separate metal casting.

7. A sand moulding chamber according to claim 6, wherein a rear end (40) of the main chamber element (21) formed by at least the chamber top wall (3), the chamber bottom wall (4), and the two opposed chamber side walls (5, 6) forms at least one machined contact face (41) in abutment with at least one corresponding machined contact face (42) of the chamber rear wall (39), and wherein the chamber rear wall (39) is connected to the main chamber element (21) in such a way that the position of the chamber rear wall (39) may be adjusted, during mounting of the chamber rear wall (39) on the mainP3624PC0040chamber element (21), in relation to the main chamber element (21) in at least two different directions being at right angles to the longitudinal direction (L) of the sand moulding chamber (1).

8. A sand moulding chamber according to any one of the preceding claims, wherein internal corners (43) formed between the chamber top wall (3) and each of the two opposed chamber side walls (5, 6) and formed between the chamber bottom wall (4) and each of the two opposed chamber side walls (5, 6) have been machined to a rounded form.

9. A sand moulding chamber according to claim 8, wherein the rounded form of said internal corners (43) has the form of an undercut (44).

10. A sand moulding chamber according to claim 8 or 9, wherein the internal side (8) of each of the chamber top wall (3), the chamber bottom wall (4), and the two opposed chamber side walls (5, 6) is lined with a respective wear plate (10, 11, 12, 13), and wherein at least one of two neighbouring wear plates meeting at a respective internal corner (43) formed between said chamber walls is provided with a chamfer (45) or bevel at an external edge of said wear plate.

11. A vertical sand moulding machine (2) including a sand moulding chamber (1) according to claim 4 and 5, wherein a first compaction cylinder (36) for operation of a swing plate system (46) is attached to and supported by the at least one machined contact face (33, 41) formed by a first one (5) of the two opposed chamber side walls (5, 6), wherein a second compaction cylinder for operation of the swing plate system (46) is attached to and supported by the at least one machined contact face (34, 41) formed by a second one (6) of the two opposed chamber side walls (5, 6), and wherein a third compaction cylinder (38) for operation of a pressing plate is attached to and supported by at least one machined contact face (35) formed by the chamber rear wall (39).

12. A sand moulding chamber (1) for a vertical sand moulding machine (2) for the production of sand mould parts, wherein the sand moulding chamber (1) includes at least aP3624PC0041chamber top wall (3), a chamber bottom wall (4), and two opposed chamber side walls (5, 6), wherein all said chamber walls (3, 4, 5, 6) extend in a longitudinal direction (L) of the sand moulding chamber (1) and all said chamber walls (3, 4, 5, 6) are formed of cast metal, wherein at least one of said chamber walls (3, 4, 5, 6) is provided with at least one sand filling opening (7), wherein the sand moulding chamber (1) includes machined contact faces and non-machined surfaces, wherein at least part of an internal side (8) of each said chamber wall (3, 4, 5, 6) is provided with at least one machined contact face (9) for attachment of a wear plate (10, 11, 12, 13), wherein an external side (14) of the sand moulding chamber (1) forms a number of tie rod bearing extensions (15) having bores (16) for insertion of tie rod guide bushings (17) for guiding, in the longitudinal direction (L) of the sand moulding chamber (1), respective tie rods (18) of a compacting system (19) of the vertical sand moulding machine (2), and wherein each tie rod bearing extension (15) includes at least one machined contact face (20) for contacting the respective tie rod guide bushing (17), characterised in that at least the chamber top wall (3), the chamber bottom wall (4), and the two opposed chamber side walls (5, 6) together form a main chamber element (21) made from one single metal casting (22), in that internal corners (43) formed between the chamber top wall (3) and each of the two opposed chamber side walls (5, 6) and formed between the chamber bottom wall (4) and each of the two opposed chamber side walls (5, 6) have been machined to a rounded form, and in that, preferably, the rounded form of said internal corners (43) has the form of an undercut (44).

13. A sand moulding chamber according to claim 12, wherein the internal side (8) of each of the chamber top wall (3), the chamber bottom wall (4), and the two opposed chamber side walls (5, 6) is lined with a respective wear plate (10, 11, 12, 13), and wherein at least one of two neighbouring wear plates meeting at a respective internal corner (43) formed between said chamber walls is provided with a chamfer (45) or bevel at an external edge of said wear plate.

14. A set of at least four wear plates (10, 11, 12, 13) for use in lining a sand moulding chamber according to claim 12 or 13, wherein at least one of two neighbouring wearP3624PC0042plates meeting at a respective internal corner (43) formed between said chamber walls is provided with a chamfer (45) or bevel at an external edge of said wear plate.

15. A set of at least four wear plates (10, 11, 12, 13) for use in lining a sand moulding chamber for a vertical sand moulding machine (2) for the production of sand mould parts, wherein the sand moulding chamber (1) includes at least a chamber top wall (3), a chamber bottom wall (4), and two opposed chamber side walls (5, 6), wherein all said chamber walls (3, 4, 5, 6) extend in a longitudinal direction (L) of the sand moulding chamber (1) and all said chamber walls (3, 4, 5, 6) are formed of cast metal, wherein at least one of said chamber walls (3, 4, 5, 6) is provided with at least one sand filling opening (7), wherein the sand moulding chamber (1) includes machined contact faces and non-machined surfaces, wherein at least part of an internal side (8) of each said chamber wall (3, 4, 5, 6) is provided with at least one machined contact face (9) for attachment of a wear plate (10, 11, 12, 13), characterised in that at least the chamber top wall (3), the chamber bottom wall (4), and the two opposed chamber side walls (5, 6) together form a main chamber element (21) made from one single metal casting (22), in that internal corners (43) formed between the chamber top wall (3) and each of the two opposed chamber side walls (5, 6) and formed between the chamber bottom wall (4) and each of the two opposed chamber side walls (5, 6) have been machined to a rounded form, and in that, preferably, the rounded form of said internal corners (43) has the form of an undercut (44), wherein at least one of two neighbouring wear plates meeting at a respective internal corner (43) formed between said chamber walls is provided with a chamfer (45) or bevel at an external edge of said wear plate.

16. A method of producing a sand moulding chamber (1) for a vertical sand moulding machine (2) for the production of sand mould parts, the sand moulding chamber (1) including at least a chamber top wall (3), a chamber bottom wall (4), and two opposed chamber side walls (5, 6), all said chamber walls (3, 4, 5, 6) extending in a longitudinal direction (L) of the sand moulding chamber (1), wherein at least one of said chamber walls (3, 4, 5, 6) is provided with at least one sand filling opening (7), wherein the sand moulding chamber (1) includes machined contact faces and non-machined surfaces, wherein an external side (14) of the sand moulding chamber (1) forms a number of tieP3624PC0043rod bearing extensions (15) having bores (16) for insertion of tie rod guide bushings (17) for guiding, in the longitudinal direction (L) of the sand moulding chamber (1), tie rods (18) of a compacting system (19) of the vertical sand moulding machine (2), the method including the steps of forming in a metal casting process the chamber top wall (3), the chamber bottom wall (4), and the two opposed chamber side walls (5, 6), subsequently machining on at least part of an internal side (8) of each said chamber wall (3, 4, 5, 6) at least one contact face (9) for attachment of a wear plate (10, 11, 12, 13), and machining on each tie rod bearing extension (15) at least one contact face (20) for contacting the respective tie rod guide bushing (17), characterised by casting together at least the chamber top wall (3), the chamber bottom wall (4), and the two opposed chamber side walls (5, 6) as one single metal casting (22), installing said one single metal casting (22) in a machining centre and subsequently machining, before deinstalling said one single metal casting (22) from the machining centre, the at least one contact face (9) for attachment of a wear plate (10, 11, 12, 13) and the at least one contact face (20) for contacting the respective tie rod guide bushing (17), the method including the further step of machining to a rounded form internal corners (43) formed between the chamber top wall (3) and each of the two opposed chamber side walls (5, 6) and formed between the chamber bottom wall (4) and each of the two opposed chamber side walls (5, 6), and wherein, preferably, during the casting of said one single metal casting (22), the internal corners (43) formed between the chamber top wall (3) and each of the two opposed chamber side walls (5, 6) and formed between the chamber bottom wall (4) and each of the two opposed chamber side walls (5, 6) are formed without an undercut (44), and wherein, during the step of machining said internal corners (43) to a rounded form, said rounded form is machined to form an undercut (44).

17. A method of producing a sand moulding chamber according to claim 16, wherein the method includes the further step of, after installing said one single metal casting (22) in the machining centre and before deinstalling said one single metal casting (22) from the machining centre, machining on the external side (14) of the sand moulding chamber (1) at least one contact face (33, 34, 35, 41) for attachment of at least one compaction cylinder (36, 38) or piston of the compacting system (19).

Images