A method for producing a green compact uses a pressing tool including a die, a first punch to be displaced in an axial direction, a second punch to be displaced in a radial direction through a channel in the die and a receptacle having a filling opening. The method includes locating the second punch before or during filling of a powdery material into the receptacle so as to be outwardly offset in the radial direction relative to an inner peripheral surface, filling the powdery material into the receptacle, and moving at least the first punch and the second punch and compressing the material in the receptacle, with the second punch being moved in the radial direction toward the receptacle only so far that it is disposed flush with a region of the inner peripheral surface. A pressing tool, a green compact and a sintered part are also provided.

A method for forming a multi-layer blank of a ceramic material including the steps of: providing a mold that includes at least one side wall surrounding a lower press plunger to form a cavity therebetween, wherein the lower press plunger has a movable pin; filling into the mold a first ceramic material; extending the movable pin from an upper surface of the lower press plunger and into the cavity; pressing a first upper press plunger against the first ceramic material so that a first open cavity is formed while at least a portion of the first upper press plunger is in contact with the movable pin to maintain the through-hole through the first layer; filling into the mold a second ceramic material of a different composition; extending the movable pin from an upper surface of the first layer and into the first open cavity; and pressing a second upper press plunger against the second layer so that a second open cavity is formed in communication with the through-hole that extends through the first and second layers to form the blank.

A method for forming a multi-layer blank of a ceramic material including the steps of: providing a mold that includes at least one side wall surrounding a lower press plunger to form a cavity therebetween, wherein the lower press plunger has a movable pin; filling into the mold a first ceramic material; extending the movable pin from an upper surface of the lower press plunger and into the cavity; pressing a first upper press plunger against the first ceramic material so that a first open cavity is formed while at least a portion of the first upper press plunger is in contact with the movable pin to maintain the through-hole through the first layer; filling into the mold a second ceramic material of a different composition; extending the movable pin from an upper surface of the first layer and into the first open cavity; and pressing a second upper press plunger against the second layer so that a second open cavity is formed in communication with the through-hole that extends through the first and second layers to form the blank.

The invention relates to a press for producing dimensionally stable preforms from material that is substantially in the form of a powder, in particular iron powder and or ceramic powder, with a tool comprising an upper die and a lower die, wherein the upper die and the lower die respectively comprise at least one die, wherein a first die and a second die are arranged together, one sliding in the other, as the upper die or lower die and respectively have a first end and a second end, lying opposite the first end, wherein at least one of the two dies spreads out along one portion to such an extent that the second end thereof has a width that at least approaches an outer diameter of a die holder associated with the second end. This allows presses of a compact form to be made available for producing dimensionally stable preforms of high quality and great complexity.

The invention relates to a method for powder pressing at least two pressed parts, in particular ceramic powder pressed parts and/or metal powder pressed parts, wherein a first powder (17) for pressing a first pressed part is filled into a first cavity (13) of a die (12) with a first filling level and a second powder (18) for pressing a second pressed part is filled into a second cavity (14) of the die (12) with a second filling level, wherein the first and second filling levels are individually adjusted. Preferably, the first powder is filled via a first filling shoe and the second powder is filled via a second filling shoe, wherein the two filling shoes, at least temporarily, are not moved simultaneously. A powder pressing device is also claimed which is suitable for implementing the aforementioned method.

A powder compaction mold includes a die and upper and lower punches configured to fit into the die and is configured to compress a powder between the upper and lower punches to manufacture a powder compact. Of the members forming the powder compaction mold, at least one of two members in sliding contact with each other has therein a vent passage through which gas is vented from a filling space for the powder surrounded by the die and the lower punch to an outside of the powder compaction mold. The vent passage has a gas intake port that is open to a clearance section formed between the two members and connecting to the filling space.

A method for manufacturing a jewel of the polycrystalline type, in particular for a timepiece, the jewel including, for example, poly-ruby of the type al2O3Cr or Zirconia of the type ZrO2, the method including a first step of producing a precursor, and a second step of pressing the precursor in order to form a body, the pressing being carried out using a pressing device provided with an upper die and a lower die defining a pressing space in which the precursor is disposed, the device being provided with a wire passing through at least part of the lower die to open out into the pressing space, the lower die being capable of sliding about the wire, the pressing taking place by bringing the lower die and the upper die closer to one another to form a body comprising a bottom face provided with a hole.

A method for manufacturing a jewel for a timepiece, the jewel including, for example, poly-ruby of the Al2O3Cr type or Zirconia of the ZrO2 type, including first producing a precursor and a then pressing the precursor in order to form a body, the pressing being carried out using a pressing device provided with an upper die and a lower die defining a pressing space wherein the precursor is disposed, the upper die including a concave portion of oblong shape, the device having a wire at least partially traversing the lower die to open into the pressing space, the lower die being able to slide around the wire, the pressing being carried out by bringing the lower die and the upper die closer together to form a body including an upper face provided with a dome and a lower face provided with a hole extending at least partially into the dome.

A compression device, means for controlling the compression device, a drum having an inner chamber, means for rotating the drum, and first and second delivery devices for delivering first and second materials into the inner chamber of the drum while the drum is rotating. The compression device compresses the first and second material in the inner chamber of the drum while the drum is rotating about the center of the drum in response to the means for controlling the compression device. The apparatus may include a stirring device; and a means for controlling the stirring device; wherein the stirring device is configured with respect to the drum so that the stirring device can be moved up and down to a desired depth within the drum and rotates within the inner chamber of the drum to stir the first and second materials in the drum while the drum is rotating.

A compression device, means for controlling the compression device, a drum having an inner chamber, means for rotating the drum, and first and second delivery devices for delivering first and second materials into the inner chamber of the drum while the drum is rotating. The compression device compresses the first and second material in the inner chamber of the drum while the drum is rotating about the center of the drum in response to the means for controlling the compression device. The apparatus may include a stirring device; and a means for controlling the stirring device; wherein the stirring device is configured with respect to the drum so that the stirring device can be moved up and down to a desired depth within the drum and rotates within the inner chamber of the drum to stir the first and second materials in the drum while the drum is rotating.