Riser with movable gate

Abstract

The invention relates to a riser comprising a riser body having a riser opening for the flow of liquid metal and a movable gate arranged in the riser opening. The gate tapers at an end opposite the riser body and has at least one circumferential flange in the tapering. Furthermore, the invention relates to an assembly comprising a riser, a pattern plate and a centering pin passing through the gate, and to the use of the riser or the assembly for metal casting.

Description

Technical Field

[0001] The invention relates to a riser, comprising a riser body and a movable gate, the riser body having a riser opening for flowing liquid metal, and the gate being arranged in the riser opening. The gate tapers at the end opposite to the riser body and has at least one circumferential flange in the taper, and optionally has a circumferential lip at the end of the taper (i.e. in the outlet), which is turned inwards. In addition, the invention relates to an assembly comprising the riser, a pattern plate and a centering pin passing through the gate, and to a use of the riser or the assembly for metal casting. Background Art

[0002] Riser (also known as feeding structure) is used for casting metal in casting mold. Riser usually has a riser cavity configured to receive molten metal. The molding material used to make the casting mold and form the casting mold surrounds the riser. The casting space inside the casting mold, which is arranged to receive liquid metal, has a passage leading to the riser cavity, and then, during the casting process, a portion of the liquid metal filled into the casting mold enters the riser cavity. Then, the molten metal rising into the riser forms a metal static pressure, and since the casting shrinks when solidifying, it is intended to flow back into the casting mold when the casting solidifies, so as to compensate for the volume loss caused by the shrinkage of the casting during solidification. The casting mold is produced by means of a pattern including a pattern plate, that is, the molding material is obtained by molding the molding material mixture using the pattern and hardening the molding material mixture.

[0003] In order to ensure the metal reflux in the riser, it is necessary to ensure that the metal in the riser remains liquid when the metal inside the casting mold has at least partially solidified to form a casting. For this purpose, at least a portion of the riser (usually the riser body) is usually made of heat insulating and / or exothermic material.

[0004] When the liquid metal enters the riser, the exothermic material is excited due to the high temperature at that time. At this time, an exothermic reaction automatically occurs in the riser material, which allows heat energy to be supplied to the metal in the riser for a certain period of time, and the metal in the riser cavity and the metal in the transition zone to the casting cavity of the casting mold remain in a liquid state. If the riser body is exothermic, the cover (if present) does not necessarily have to be exothermic and may also be, for example, thermally insulating (or neither).

[0005] Insulated risers are designed so that the liquid metal in the riser body cools slower than the liquid metal in the casting cavity because the riser material in the riser provides better insulation. Typically, the riser body is insulated, but the cover (if present) does not necessarily have to be insulated as well. The surrounding hardened molding material also has an insulating effect.

[0006] Risers are often used in conjunction with a break core (also called a necking core). A break core is an intermediate piece with a channel that connects the mold cavity and the riser cavity (such as a gate). The diameter of the channel is sized so that it decreases in size from the riser cavity to the mold cavity, thereby knocking off the break core (neck-down) near the casting surface. The break core can be made of the riser material of the riser body, but can also be made of metal, plastic or cardboard.

[0007] The riser can be mounted on a horizontal pattern plate or a vertical pattern plate. In the case of a vertical pattern plate, the riser is also called a side riser. A side riser is known from DE 3423220 A1, which comprises a riser base, which is attached laterally to the mold pattern and has a riser opening for the liquid metal, and a riser part, which is arranged on the riser base. The riser part arranged on top of the riser base forms a riser cavity, the majority of the volume of which is arranged above the horizontally extending riser axis or gate axis passing through the riser opening in the riser base.

[0008] In order to form a fracture edge, a riser having a tubular body as a gate has been proposed in EP 1 345 716 B1, wherein the gate tapers towards the end facing the casting.

[0009] EP1850987 B1 discloses a riser with a movable gate. Since the gate can be moved into the riser cavity for transportation, the riser can be easily packaged and transported.

[0010] The riser is usually mounted on a centering pin, which can also be designed as a spring mandrel, also called a spring pin. In the case of a rigid centering pin, during compaction of the molding material mixture, the centering pin can push through the cover of the riser body. The spring mandrel shortens its length via a spring mechanism and thus accommodates the movement. The centering pin is mounted on a pattern or pattern plate.

[0011] Purpose of the Invention

[0012] The object of the present invention is to provide an improved riser with a movable gate. The gate should stand firmly on the pattern plate of the pattern or on the possibly beveled base of the centering pin and should remain in place during the compaction of the molding material mixture. The centering pin is mounted on the pattern plate and is removed together with the pattern plate. The gate should be able to withstand the forces applied to the riser during the compaction of the molding material mixture, especially when the forces act asymmetrically. During the compaction of the molding material mixture, angular forces may act on the riser, causing the gate to bend around the centering pin at the bottom of the fracture core, resulting in poor fracture edges. In addition, the gate should not fall back into the cavity of the riser body or move away from the pattern plate (or away from the base of the centering pin). Therefore, during the demoulding process, a clean fracture edge should be formed near the surface of the casting. Usually, this cannot be ensured if the gate is bent due to angular forces (especially in the first end section). Summary of the invention

[0013] This object is achieved by the subject matter of the independent claims. Advantageous embodiments are subject matter of the dependent claims or are discussed below.

[0014] The riser shall include at least:

[0015] A riser body having a cavity; and

[0016] a gate for connecting the casting mold to the cavity of the riser body via the riser opening,

[0017] wherein the gate is formed by a tubular body having a first end section with an outlet and a second end section opposite the first end section, the first end section being connected to the mold via the outlet and the second end section being connected to the cavity of the riser body,

[0018] wherein the first end section has a tapered section, and the tapered section tapers toward the outlet,

[0019] wherein the gate is movably arranged in a gate opening of the feeder body and the gate can be at least partially pushed into the feeder body via the second end section, and

[0020] The tapered section has a plurality of regions, which include at least a first groove region having a groove and at least one flange region adjacent to the first groove region and having a flange, so that in the tapered section, a series of surfaces orthogonal to the gate axis are formed in the direction from the cavity of the riser body toward the outlet, wherein the size of the surface in the first groove region decreases, and the size of the surface in the transition zone from the first groove region to the flange region increases to form a flange that bulges outward and the size decreases again when the flange shrinks.

[0021] The tapered section may optionally have an inwardly formed circumferential lip at the outlet. The inwardly formed circumferential lip may be substantially perpendicular to the gate axis.

[0022] According to an optional embodiment of the present invention, the tapered section has a second groove (19) adjacent to the flange in the direction from the riser cavity toward the outlet, and preferably, the first groove has a deeper necking portion in the tapered section than the second groove.

[0023] According to an optional embodiment of the present invention, the gate has an outwardly protruding stopper at the second end section, more specifically at the end of the second end section, and in particular, the stopper is an outwardly bent edge.

[0024] According to an optional embodiment of the present invention, the gate is rotationally symmetric along the gate axis.

[0025] According to an optional embodiment of the present invention, the flange has an (average) flange height, and the flange height is smaller than the (average) length of the first necking portion of the (first) groove, more specifically, it is smaller by more than 10%, and / or in the case where a second necking portion is present, the (average) length of the second necking portion is smaller than the (average) length of the first necking portion of the first groove, more specifically, it is smaller by more than 30%.

[0026] According to another optional embodiment of the present invention, the first volume portion (20) below the envelope surface of the first groove is larger than the second volume portion below the envelope surface of the second groove, more specifically, larger by more than 50%.

[0027] According to another alternative embodiment of the present invention, the first groove and the flange and the second groove (if present) may be formed by knurling.

[0028] According to another alternative embodiment of the invention, the first groove and the flange and the second groove (if present) are joined to each other by a bend rather than by an angle edge.

[0029] The invention also relates to an assembly or assembly device comprising the above-mentioned riser and also comprising a template and a pin. The pin end is arranged on the template, wherein the gate is guided by the pin and the pin extends through the riser opening and extends into the cavity of the riser. The pin end abuts against the inner wall of the riser body or against a cover opposite to the riser opening, and the outlet of the gate abuts against the base of the pin or against the template.

[0030] The invention also relates to the use of a feeder as defined in the above assembly device for supplying liquid metal in metal casting.

[0031] The tapered section may have a second groove area adjacent to the flange in a direction from the riser cavity toward the outlet (or from the second end section to the first end section) so that the size of the surface continues to decrease when leaving the flange and then increases when leaving the second groove area having the second groove.

[0032] The surface at the start of the first groove area is greater than the surface at the end of the second groove area; or in the absence of the second groove area, the surface at the start of the first groove area is greater than the surface at the end of the flange area.

[0033] Preferably, the surface at the deepest point of the constriction of the first groove region is larger than the surface at the deepest point of the constriction of the second groove region.

[0034] Preferably, the surface at the deepest point of the constriction of the first groove region is larger than the surface where the flange region ends (in the absence of the second groove region).

[0035] Preferably, the flange area and the one or more groove areas do not have any corner edges or angled edges (where two surfaces meet at an angle along an edge), but only rounded transitions.

[0036] Therein, the stability of the gate is such that the rounded transition (or less preferably the edge) does not deform during compaction and the gate reacts to the compaction pressure only by moving into the riser cavity, wherein the riser body slides over the gate towards the pattern plate.

[0037] In addition, the volume portion (first volume portion) enclosed by the envelope surface applied tangentially to the highest point of the flange on one side and tangentially to the nearest highest point in the direction of the second end portion is larger than the second volume portion below the envelope surface applied tangentially to the highest point of the flange on one side and tangentially to the nearest highest point in the direction of the first end portion.

[0038] The first volume actually acts as a storage volume which presses against the gate during compaction of the molding material mixture. Thus, during compaction, the compaction force exerted on the gate acts in the direction of the pattern plate or mold cavity. In particular, the first volume is 30% larger, preferably 50% larger, than the second volume.

[0039] Specifically, the tapered section has a flange and a groove adjacent to the flange, or has a flange and two grooves located on both sides of the flange.

[0040] The tapered section, and more specifically the entire gate, will not deform during the compaction of the molding material. The gate material is formed to have appropriate rigidity. Another reason why the gate will not deform is the fact that the gate is movable.

[0041] According to one embodiment, the first end section of the gate at the outlet has an inwardly formed circumferential lip. This inwardly formed circumferential lip improves the formation of the fracture edge and strengthens the gate, which is not only reflected in the contact surface, but also prevents the gate from deforming when the gate is subjected to angular forces, that is, forces perpendicular to the gate axis. In order to form the circumferential lip, the gate is bent inwardly at the outlet, more specifically, approximately perpendicular to the gate axis. For example, the width of the lip corresponds to about 1% to 20% of the outlet diameter. In any case, the width of the lip is 0.3 mm to 5 mm, more specifically 0.5 mm to 3 mm.

[0042] According to one embodiment, the gate is rotationally symmetrical, in particular, the gate is rotationally symmetrical along the gate axis. However, the gate may also be oval, more particularly, the first end section of the gate is oval and the second end section is round. The oval gate may better rest on the thin edge of the mold pattern.

[0043] The riser according to the invention comprises at least one riser body and comprises a pouring nozzle, wherein the riser body has a riser opening for liquid metal and the pouring nozzle is movably mounted in the riser opening, more specifically, the pouring nozzle is movably mounted in the riser opening also under the effect of its own weight. The riser body can be made of multiple parts and can, for example, include a cover. The cover is not necessarily made of the same material as the rest of the riser body.

[0044] The riser is intended for use when casting metal in a casting mold that can be separated horizontally and vertically. The riser is mounted on the pattern plate using a pin (centering pin) that is guided through the gate and riser opening and extends, for example, to the upper side of the cover or riser cavity. A recess can be provided at this location to fix the top end of the pin.

[0045] Detailed description of the invention

[0046] The gate serves as an extension of the riser opening for attachment to a pattern plate, which may also be a rotational mold pattern.

[0047] When liquid metal is poured into the casting mold, the molten metal enters the cavity via the gate and riser openings. During the casting process, the riser cavity is configured to receive the liquid metal and distribute the liquid metal via the riser openings at a later point in time. As the casting shrinks, the molten metal then flows back from the riser cavity and through the riser openings of the riser body, through the mouth and into the casting until the casting is fully solidified.

[0048] The sprue is molded from metal. When hot metal flows into the sprue, it can melt and then, together with the surrounding molding material, form a bond with the casting.

[0049] The gate rests on the pattern plate or on the base of the centering pin, wherein the base can be chamfered. In this configuration, the gate is slightly spaced from the pattern plate when it rests on the chamfered base of the centering pin. The gate remains in place even during compaction of the molding material mixture, thereby ensuring that a clear fracture edge is provided directly at the casting. The gate acts as a metal fracture core, which can be compressed by pushing the metal fracture core into the riser cavity, which ensures that a minimum of riser residue remains after the riser is knocked off. Grinding and smoothing are minimized and can usually even be omitted.

[0050] When the molding material is compacted, the riser body moves toward the pattern relative to the gate. At this time, the gate and the part of the second end section thereof slide into the riser opening and into the riser cavity.

[0051] At the same time, during compaction, the molding material mixture firmly presses the gate (i.e., the contact surface of the gate) against the base of the pattern plate or the centering pin, because during compaction, the molding material mixture can cling to the flange during the compaction movement and fill in the first volume. The gate moves toward the casting or mold cavity and abuts against the base of the pattern plate or the centering pin. Thus, a connection is formed between the mold cavity and the gate. When the molding material mixture is compacted, the flange and the groove cause the gate to be pressed against its contact surface.

[0052] At the same time, the flange and groove have the effect of stiffening the gate, thereby making it less susceptible to deformation when subjected to angular forces, particularly near the outlet, where deformation would interfere with the formation of a clean fracture edge. Likewise, the optional circumferential lip also stiffens the gate.

[0053] The gate can be preassembled and then transported in a space-saving and safe manner. The riser can be turned upside down and the gate can be stored (at least partially) inside the riser body (i.e., the riser cavity), thereby saving space. According to a preferred embodiment, when the riser is turned back to its use position (wherein the gate faces the template or the casting mold), the gate slides out from the inside of the riser body due to its own weight until the gate moves downward and the upper stop is contacted. In this assembly position, the riser can be arranged on the top of the pin, and the gate may have slid into the cavity of the riser body to a certain extent before. If appropriate molding pressure is applied after filling the molding material mixture, the gate can be pushed back into the riser cavity (the distance the gate is pushed back is a part of the distance it is moved out), so that the riser body can move toward the template in response to the volume reduction caused by the compaction of the molding material.

[0054] For the purposes of the present invention, a gate is understood to mean in particular a tubular body as described in DE 102005008324 A1. In addition to tubular gates, ie gates with a circular cross section, oval cross sections are also possible, which are obtained, for example, by compressing the tubular gate.

[0055] The gate tapers towards its first end section (taper). The second end section forms a shaft that can be moved into the riser cavity. If necessary, a shaft flange can be provided at the location where the taper turns into the shaft or only in the shaft section, which serves as a stop when the gate moves through its shaft section into the riser cavity of the riser body and passes through the riser opening.

[0056] The gate can have different lengths. Common lengths are approximately between 15 mm and 300 mm, more specifically between 35 mm and 100 mm. The length of the gate is selected to be at least the distance between the bridge riser and the mold pattern or casting mold before molding. The inner diameter of the gate, more specifically the inner diameter of the outlet, can generally be selected as required; however, the opening should be large enough to ensure that during the casting and solidification process, the molten metal can flow into or out of the riser, depending on the required volume and the necessary time interval. Since according to one embodiment of the present invention, the gate is inserted into the riser body, the diameter of the gate depends on the diameter of the riser opening for the gate.

[0057] Depending on the material used, the wall thickness of the gate is typically between 0.05 mm and 5 mm, more specifically between 0.15 mm and 0.5 mm.

[0058] The length of the gate and the height of the cavity of the riser body are preferably dimensioned so that in the insertion position in which the riser is normally transported, the gate is fully inserted into the riser cavity of the riser body, whereby the gate no longer extends beyond the riser opening, taking into account the wall thickness of the riser opening, where appropriate.

[0059] Specifically, the gate is made of metal, and more specifically, made of a metal similar to the casting scheme, such as an aluminum sheet, an iron sheet, or a steel sheet.

[0060] In one embodiment, the gate has a stop at the end facing the riser cavity. The stop is arranged on the gate at such a position that, when the gate is pulled out to the maximum, the stop is still located inside the riser cavity. When the gate is pulled out of the riser body, the stop abuts, for example, against the bottom of the riser cavity, i.e., against the region of the bottom adjacent to the riser opening.

[0061] In general, the stop can have any design as long as it is ensured that the gate does not fall out of the riser opening. The stop can, for example, be formed as a thickening located on the outer side of the gate and extends around the gate along the periphery of the gate in the form of a flange. A separate extension can also serve as a stop. Typically, the stop is made of the same material as the gate. However, the stop can also be made of a different material. Preferably, both the gate (at least in its second end section) and the stop are circular, wherein the stop extends around the gate at the upper end in a manner similar to a brim.

[0062] For example, the gate can be manufactured by deep drawing and knurling. In the case of deep drawing, the metal sheet is formed into a seamless shape in one or more processes. Whether the starting material is a round plate or a blank, the starting material is inserted between the upper die and the lower die and is pressed into a cup shape during the downward movement of the drawing punch. The bottom of the cup is perforated and the edge is cut. A metal gate with a circumferential lip and a circumferential edge is thus formed, and the metal gate is finally given a final shape by knurling the tapered section. During the pressing-knurling process, the deep drawn gate is pressed against another die (knurling wheel) so that both rotate. The shape of the die is transferred to the gate, in which a flange and one or more grooves are integrated. In this way, one or more groove areas and one or more flange areas are formed with rounded edges.

[0063] The riser body can be made of any heat-insulating and / or exothermic material known in the prior art to ensure that the molten metal in the riser solidifies later than the casting itself. For example, the exothermic material disclosed in DE19925167A1 can be envisioned as a possible riser material. Risers made of insulating materials are also common and feasible. Materials that can be imagined as possible materials are well known to those skilled in the art. Depending on the specific casting, it may be preferred to have an exothermic and / or heat-insulating riser.

[0064] The riser body may have a cover opening with a cover. The cover opening and the riser opening are arranged on two opposite surfaces in the riser body. In particular, the riser body is made of two parts (eg, a riser bowl and a riser cover). BRIEF DESCRIPTION OF THE DRAWINGS

[0065] The present invention will now be further described with reference to the following drawings. In the drawings:

[0066] Figure 1 is a longitudinal section of a riser with a movable gate, wherein the gate is in the form of a tubular body and is in an extended position;

[0067] Figure 2 is a longitudinal section of the riser, wherein the tubular body is partially pushed into the riser cavity; and

[0068] Figure 3 is a longitudinal section of a riser, wherein the tubular body is pushed into the riser cavity;

[0069] Figure 4 is a top view of a gate viewed perpendicular to a gate axis, the gate having a flange, a first groove, and a second groove in a tapered portion;

[0070] Figure 5 It is based on the interception along the gate axis. Figure 3 A cross section of a gate of , wherein the horizontal surface and the envelope surface are shown with auxiliary lines; and

[0071] Figure 6 is based on Figure 3 3D view of the gate in a tilted position. DETAILED DESCRIPTION

[0072] Figures 1 to 3 It is only used to illustrate the movement of the gate and to indicate the position of the gate in the riser body. The gate is only shown schematically, so that the first groove, the second groove and the flange in the tapered section are not visible. The groove and the flange are Figures 4 to 6 More specifically, Figure 5 It is shown in FIG. 1 , which shows only the gate of the riser or only a partial view of the gate.

[0073] Figure 1 is a longitudinal section of a riser according to the invention, which extends parallel to the gate axis 12. The riser consists of a riser body 1 and a gate 2. The riser body consists of two parts: an upper riser part 3 (also called a cap) and a lower riser part 4.

[0074] The upper riser part 3 and the lower riser part 4 together form a riser cavity 5 of the riser body 1. In addition, a recess 6 is provided in the upper riser part 3, which receives the top end of a pin 13 for positioning the riser on the pattern plate. The upper riser part 3 and the lower riser part 4 are connected to each other by a joint 7. A riser opening 8 is provided in the lower riser part 4, which allows inflow and outflow of the riser cavity 5. The gate 2 is movably inserted into the riser opening 8.

[0075] The gate 2 has a circular cross section. A stopper 9 is provided at the end of the gate facing the riser cavity 5, which surrounds the outer periphery of the gate 2. The diameter of the gate 2 at the end facing the riser cavity 5 matches the diameter of the riser opening 8, so that the gate 2 can be pushed into or pulled out of the riser cavity 5. The gate 2 tapers to a taper 10 at its end opposite to the cavity, which helps to form a breaking edge after the casting mold is made. Figure 1The riser is shown in a state in which the gate 2 has been completely moved out of the riser body 1. In this case, the stop 9 is in contact with the bottom 11 of the riser cavity 5, thereby preventing the gate 2 from falling out. This state occurs, for example, when the riser is taken out of its packaging and slid over the pin and then just rests on the end of the pin, so that the gate 2 is moved out to the maximum extent. When this pin end of the pin 13 is then rested in the recess 6 on the top surface of the upper riser part 3, the gate 2 is pushed back a short distance into the riser cavity. The gate 2 is inserted in the riser opening of the riser body 1 so that the gate 2 only generates a small resistance when moving.

[0076] Figure 2 The state in which the gate 2 is partially inserted into the riser body 1 is shown, and the compaction of the molding material 16 around the riser has been completed. Figure 2 This corresponds to the state of the molding material 16 after it is compacted during the production of the casting mold. When the molding material mixture is compacted, the riser body 1 moves toward the gate 2. Since the tapered end of the gate 2 abuts against the pattern plate 14 of the mold pattern, the riser body 1 and the gate 2 move relative to each other, wherein the gate 2 itself does not move. Figure 1 In contrast, the double arrow 15 shows the Figure 1 to Figure 2 , how the distance between the lower edge of the riser body and the template plate 14 is reduced.

[0077] Figure 3 The figure shows a state which is adopted, for example, for transporting a feeder according to the invention. In this state, the feeder is arranged relative to Figure 1 The position shown in FIG. 1 is inverted so that the gate 2 moves into the cavity 5 of the riser body 1 under the influence of gravity.

[0078] In this state, the gate 2 abuts against the top surface of the upper riser part 1 on the side of the cavity 5 opposite to the riser opening 8. In this state, the length of the gate 2 is preferably selected so that the gate is completely received by the riser body 1, thereby making the taper 10 of the gate 2 not protrude beyond the end of the riser opening 8. Therefore, the gate will not be damaged during transportation.

[0079] Figure 4 A side view of a gate 2 with a tapered section 10 is shown. In this enlarged view, the flange 17 and the first and second grooves 18, 19 are visible. The flange 17 and the two grooves 18, 19 are knurled and integrated into the tapered section 10. All transitions in the tapered section 10 are rounded transitions, not corner edges or corner butt edges with essentially straight surfaces. The tubular body of the gate 2 above the tapered section 10 has a uniform diameter. At the end of the tubular body of the gate 2, the tube is bent upwards in the form of a circumferential edge. This edge is the stop 9.

[0080] The second end section forms the axis of the gate 2 , which can fully or partially enter the riser cavity 5 . Figure 5 An optional circumferential shaft flange 33 is shown at the transition from the tapered section to the shaft portion, which may act as a stop for inserting the gate 2 with its shaft portion through the riser opening 8 into the riser cavity 5 of the riser body 1 .

[0081] Figure 5 A cross section of the gate 2 is shown taken along the gate axis 12. The horizontal lines are surfaces extending perpendicular to the plane of the paper and the gate axis is the surface normal to these surfaces. In the tapered section 10, the size of these surfaces decreases towards the outlet 30, and the tapered section 10 has a plurality of regions, which include at least a first groove region 28 and a flange region 27 adjacent to the first groove region, so that a series of surfaces orthogonal to the gate axis are formed in the tapered portion, wherein the size of the surface in the first groove region 28 decreases, and the size of the surface in the transition zone from the first groove region 28 to the flange region 27 first increases to form the outwardly curved flange 17 and decreases again when the flange 17 subsides (begins to decrease).

[0082] The flange 17 is adjacent to the second groove 19, and the first groove 18 forms a deeper necking 24 (also orthogonal to the gate axis) in the tapered section than the second necking 25 (orthogonal to the gate axis) about the second groove 19. In the same way, the average flange height 31 can be determined by a tangent 32 to the flange height.

[0083] When the tangent 22' is applied to the highest point of the flange and brought to the gate in the direction of the arrow so that the other end portion is applied to the nearest highest point in the direction of the second end portion, the multiple tangents 22 thus applied form an envelope surface in the plane of the gate axis and form the first volume 20 below the envelope surface. The constriction 24 then represents the average depth of the first groove 18.

[0084] In the case where the second groove 19 is provided, Figure 5 As shown, a tangent line 23 can be applied again, first to the highest point of the flange 17 and then to the gate in the direction of the outlet.

[0085] The plurality of second tangent lines 23 thus applied form a second envelope surface in the plane of the gate axis and form a second volume portion 21 below the second envelope surface. The constriction 25 then represents the (average) depth of the second groove 18.

[0086] Figure 6 Shown according to Figure 3 The figure shows the stopper 9, when the gate is as Figure 1 When fully extended as shown, the stop rests on the bottom 11 of the riser cavity around the riser opening 8. The stop 9 is shaped like a hat brim and is bent approximately at a right angle (perpendicular to the gate axis) at the end of the second end portion. At the end of the tapered section 10 or the first end section, a gate 30 can be seen, into which a circumferential lip 26 extends, which is bent approximately at a right angle relative to the gate axis 12, forming a circumferential narrow reinforcing rib. The lip 26 is arranged on the base of the pin 13 or on the template plate 14. The pin then extends through the outlet 30 (neither of which is shown). The second groove 19 and the flange 17 are also visible.

[0087] Reference Symbols List:

[0088] Riser body 1

[0089] Gate 2

[0090] Upper riser part / cover 3

[0091] Lower riser part 4

[0092] Riser cavity / Riser body cavity 5

[0093] Recess 6 in the cap / upper riser section

[0094] Joint 7

[0095] Riser opening 8

[0096] Stopper 9

[0097] Tapered portion 10

[0098] Bottom of the riser cavity 11

[0099] Gate axis 12

[0100] Pin / Centering Pin 13

[0101] Template 14

[0102] Double arrow: distance from the lower edge of the riser body to the template 15

[0103] Molding material 16

[0104] Flange 17

[0105] First groove 18

[0106] Second groove 19

[0107] The first volume portion 20

[0108] The second volume portion 21

[0109] A first tangent line 22 defining the envelope surface

[0110] First cut (both sides not yet applied) 22'

[0111] The second tangent line 23 defining the envelope surface

[0112] The first necking portion 24

[0113] Second constriction 25

[0114] Lip 26

[0115] Flange area 27

[0116] First groove area 28

[0117] Second groove area 29

[0118] Exit 30

[0119] Flange height 31

[0120] Tangent line for flange height 32

[0121] Shaft flange 33

Claims

1. A riser for use in metal casting, the riser at least comprises: a riser body (1) having a riser cavity (5); and a sprue (2) for connecting a casting mold to the riser cavity (5) of the riser body (1) via a riser opening (8); wherein the sprue (2) is formed by a tubular body, and the tubular body has a first end section with an outlet (30) and a second end section opposite to the first end section, the first end section is connected to the casting mold via the outlet (30), and the second end section is connected to the riser cavity (5) of the riser body (1); wherein the first end section has a tapered section (10), and the tapered section (10) tapers towards the outlet (30); wherein the sprue (2) is movably arranged in the riser opening (8) of the riser body (1), and the sprue can be at least partially pushed into the riser body through the second end section; and wherein the tapered section (10) has a plurality of regions, these regions at least include a first groove region (28) having a groove (18) and at least one flange region (27) adjacent to the first groove region and having a flange (17), so that in the tapered section (10), a series of surfaces orthogonal to the sprue axis (12) are formed in the direction from the cavity (5) of the riser body (1) towards the outlet (30), wherein the size of the surfaces in the first groove region (28) decreases, and the size of the surfaces in the transition region from the first groove region (18) to the flange region (27) first increases to form an outwardly bulging flange (17) and then decreases again when the flange (17) contracts.

2. The riser according to claim 1, wherein, the tapered section (10) has a second groove (19) immediately adjacent to the flange in the direction from the riser cavity (5) towards the outlet (30), and preferably, the first groove (18) has a deeper necking (24) than the second groove (19) in the tapered section.

3. The riser according to at least one of the foregoing claims, wherein, the sprue (2) is made of metal.

4. The riser according to at least one of the foregoing claims, wherein, the sprue (2) has an outwardly projecting stop (9) at the second end section, more specifically at the end of the second end section, and in particular, the stop (9) is an outwardly bent edge.

5. The riser according to at least one of the foregoing claims, wherein, the sprue (2) is rotationally symmetric about the sprue axis.

6. The riser according to at least one of the foregoing claims, wherein, The flange (17) has an (average) flange height (31), and the flange height (31) is less than the (average) length of the first necking (24) of the (first) groove (18), more specifically, by more than 10%, and / or in the presence of a second necking (25), the (average) length of the second necking is less than the (average) length of the first necking (24) of the first groove (18), more specifically, by more than 30%.

7. The riser according to at least one of claims 2 to 7, wherein, a first volume portion (20) below the envelope surface of the first groove (18) is larger than a second volume portion (21) below the envelope surface of the second groove (19), more specifically, by more than 50%.

8. The riser according to at least one of the preceding claims, wherein, in the presence of the second groove (19), the first groove (18), the flange (19), and the second groove can be formed by knurling.

9. The riser according to at least one of the preceding claims, wherein, in the presence of the second groove (19), the first groove (18), the flange (19), and the second groove are joined to each other by a bent portion rather than by an angular edge.

10. The riser according to at least one of the preceding claims, wherein, the tapered section (10) further has a circumferential lip (26) formed inwardly at the outlet (30).

11. The riser according to claim 10, wherein, the circumferential lip (26) formed inwardly is formed substantially perpendicular to the gate axis (12).

12. An assembly comprising a riser according to at least one of the preceding claims and further comprising a pattern plate (14) and a pin (13), the pin end of the pin being arranged on the pattern plate (14), wherein, the gate (2) is guided by the pin (13), and the pin (13) extends through the riser opening (8) and into the cavity (5) of the riser, and the pin end abuts against the inner wall of the riser body (1) or against a cover opposite the riser opening (8), and the outlet (30) of the gate abuts against the base of the pin (13) or against the pattern plate (14).

13. Use of a riser according to at least one of claims 1 to 11 or a device according to claim 11 for supplying liquid metal in metal casting.

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