Casting device and casting method

Abstract

A casting device and casting method are provided for producing components, in particular cylinder heads. The device includes a reusable steel upper core, which can be lifted off from the component to be produced and which has a movable displacing element. The displacement element can be pressed into the component to be produced for dense feeding. In a method for producing a cylinder head by casting, wherein the steel upper core is used as a substitution for a sand cover core, for dense feeding the displacing element is pressed into the melt that forms the cylinder head in the solidified state.

Claims

1. A method of manufacturing a cylinder head by a casting method, the method comprising the acts of: providing a reusable upper steel core, rather than a sand cover core, configured to be liftable from the cylinder head to be produced, the reusable upper steel core having a movable displacement element; and pressing the movable displacement element into a melt which, in a solidified state, forms the cylinder head to be produced, such that as a result of the pressing of the movable displacement element into the melt, melt that is displaced by the pressing is distributed across an entirety of the cylinder head to be produced and a manufacturing step is performed where a clearance in the cylinder head to be produced is formed.

2. The method according to claim 1, further comprising the act of: cooling and/or heating the displacement element.

3. A method of manufacturing a cylinder head by a casting method, the method comprising the acts of: providing a reusable upper steel core, rather than a sand cover core, configured to be liftable from the cylinder head to be produced, the reusable upper steel core having a movable displacement element; and pressing the movable displacement element into a melt which, in a solidified state, forms the cylinder head to be produced, such that as a result of the pressing of the movable displacement element into the melt, melt that is displaced by the pressing is distributed across an entirety of the cylinder head to be produced; wherein the displacement element is configured as a steel pin and is pressed into the cylinder head to be produced at a position forming a spark-plug well.

4. A method of manufacturing a cylinder head by a casting method, the method comprising the acts of: providing a reusable upper steel core, rather than a sand cover core, configured to be liftable from the cylinder head to be produced, the reusable upper steel core having a movable displacement element; and pressing the movable displacement element into a melt which, in a solidified state, forms the cylinder head to be produced, wherein the displacement element is configured as a steel pin and is pressed into the cylinder head to be produced at a position forming a spark-plug well.

5. The method according to claim 4, further comprising the act of: cooling and/or heating the displacement element.

6. A method of manufacturing a cylinder head by a casting method, the method comprising the acts of: providing a reusable upper steel core, rather than a sand cover core, configured to be liftable from the cylinder head to be produced, the reusable upper steel core having a movable displacement element; and pressing the movable displacement element into a melt which, in a solidified state, forms the cylinder head to be produced, wherein the displacement element is pressed into the cylinder head to be produced at a position which, in a final state, forms a clearance in the cylinder head.

7. The method according to claim 6, wherein the clearance is a spark-plug well.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is a perspective view of a cylinder head having a feeder system according to the prior art;

(2) FIG. 2 is a sectional view of a casting device according to an embodiment of the invention for casting a cylinder head;

(3) FIG. 3 is a perspective view of the casting device from FIG. 2; and

(4) FIG. 4 is a perspective view of a cylinder head from FIG. 2.

(5) The figures are exemplary and schematic. Same reference signs refer to same parts in all figures.

DETAILED DESCRIPTION OF THE DRAWINGS

(6) A cylinder head 21 having a feeder system 20 disposed thereon is illustrated in a perspective view in FIG. 1. The feeder system 20, presently for a four-cylinder engine, contains the melt which compensates for the shrinkage of the setting component and ensures dense feeding. The feeder system 20 is surrounded by a sand cover core (not illustrated), which forms the upper termination face for the cylinder head 21 and receives the feeder system 20. The sand cover core and the feeder system 20 have a significant volume and weight.

(7) The casting device 10 according to an embodiment of the invention is illustrated in a lateral sectional view in FIG. 2, components which are irrelevant to the invention being omitted. The casting device 10 has a reusable upper steel core 1 which is liftable from the cylinder head 2 and through which a plurality of displacement elements 3, which are configured as steel pins, extend. The displacement elements 3 are movable and, by way of a controller device 7, pressable into the cylinder head 2 at a predetermined time and at a predetermined pressure. A predetermined time here means that the melt of the cylinder head 2 must not yet have set, such that the penetrating displacement element 3 leads to displacement of melt. The excess melt which is obtained by displacement is substantially distributed across the entire cylinder head 2 and serves as dense feeding. The feeder system 20 from FIG. 1 is thus obsolete.

(8) The casting device 10 from FIG. 2 is illustrated in a perspective view in FIG. 3. The upper steel core 1 can be seen from its lower side which faces the cylinder head 2. The position of the displacement elements 3 is selected so as to correlate with positions of the cylinder head 2. The position of the displacement elements 3, in the finished state, in each case form the spark-plug well. The upper steel core 1 on the surface thereof which faces the cylinder head 2 additionally has a plurality of protrusions 4 which, in the finished state of the cylinder head 2, form a cavity. The surface geometry of the upper steel core 1 may thus be selected such that a negative of the component to be produced, presently the cylinder head 2, is formed.

(9) FIG. 4 shows a perspective view of a cylinder head 2, including the positions 5 which correlate with the displacement elements 3 and which form the spark-plug wells in the cylinder head 2. An illustration of the sand core for forming the remaining cavities within the cylinder head 2 has been dispensed with. The illustrated basic mold is cast as usual in order for the cylinder head 2 to be manufactured. However, in order to ensure dense feeding, the feeder system 20 from FIG. 1 is no longer used, but instead the displacement elements 3 which are integrated into the upper steel core 1 are pressed into the partially set melt of the cylinder head 2. The casting device 10, by way of the upper steel core 1, seals tightly the component to be produced, such that the internal pressure rises on account of the displacement elements 3 being pressed in. On account of this, material shrinkage of the melt is equalized. As soon as the melt has sufficiently set such that the displacement elements 3 can be retracted again into the upper steel core 1 without causing deformation in the respective regions, the upper steel core may be lifted and the component, presently the cylinder head 2, may be removed.

(10) According to the invention, the use of an additional feeder system 9 on a component to be produced is not excluded, in particular in regions which are not in direct fluid connection with the positions 5. This means that an additional feeder system 9 may readily be disposed in regions which cannot be reached by the displaced melt material. However, in comparison with the feeder systems according to FIG. 1, the additional feeder system, in terms of the volume and weight thereof, is minimal.

(11) The invention in its embodiment is not limited to the above-stated and preferred embodiment. Rather, numerous variants which utilize embodiments which may differ in principle from the illustrated solution are contemplated. For example, the displacement element need not form a spark-plug well but, by pressing, may vacate any other clearances desired in the component to be produced.

(12) The foregoing disclosure has been set forth merely to illustrate the invention and is not intended to be limiting. Since modifications of the disclosed embodiments incorporating the spirit and substance of the invention may occur to persons skilled in the art, the invention should be construed to include everything within the scope of the appended claims and equivalents thereof.