Method for determining a parameter of a material and pressing tool for the production of a green compact

Patent metadata

Field	Value
Publication number	US-12358048-B2
Application number	US-202217726341-A
Country	US
Kind code	B2
Filing date	Apr 21, 2022
Priority date	Apr 22, 2021
Publication date	Jul 15, 2025
Grant date	Jul 15, 2025

Abstract

At least one parameter of a material is determined with a pressing tool usable for producing a green compact and a pressing tool for producing at least one green compact. The pressing tool has at least one planar surface which is formed at least in part by a die which, starting from the surface, extends along an axial direction and, on the surface, has a cavity which extends from the surface along the axial direction and has an inner circumferential surface; wherein the cavity forms a receptacle for a powdery material which can be pressed in the cavity by at least one punch plunging into the cavity along the axial direction to form the green compact.

First claim

The invention claimed is:

1. A method for determining at least one parameter of a powdery material with a pressing tool which can be used for producing a green compact, the pressing tool having at least one working plane with at least one planar surface, a die which at least partially forms the surface, a punch movable relative to the surface along an axial direction, a filling shoe for providing the powdery material, and a measuring device for determining the parameter of the powdery material used for producing the green part; wherein the die extends from the surface along the axial direction and has at the surface a cavity extending from the surface along the axial direction and having an inner circumferential surface; the cavity forming a receptacle for the powdery material, which can be pressed in the cavity into the green compact by at least the punch plunging into the cavity along the axial direction; the filling shoe being movable along the surface; wherein the measuring device has an opening at the surface, an outlet opening that is closeable, and a constant volume directly adjoining the opening at the surface and the outlet opening; wherein the opening at the surface for the measuring device is spaced from the cavity along a radial direction; wherein the method comprises at least the following steps:
a) filling the filling shoe with the powdery material from a storage container;
b) moving the filling shoe over the surface and across the opening of the measuring device;
c) at least partially filling the constant volume of the measuring device with the powdery material from the filling shoe via the opening of the measuring device;
d) carrying out the determination of the at least one parameter of the powdery material by the measuring device and removing the powdery material from the constant volume of the measuring device via the outlet opening of the measuring device.

2. The method according to claim 1 , wherein the filling shoe is filled in step a) in a starting position, is moved in step b) from the starting position to the opening of the measuring device, and is moved after step c) in a step i) back to the starting position.

3. The method according to claim 2 , the method further comprising a step ii) in which the filling shoe is moved towards the cavity and the receptacle is filled from the filling shoe; wherein the step ii) occurs before step b), immediately after step b), or immediately after step c); wherein the method further comprising a step iii) in which the punch plunges into the cavity for pressing the powdery material and for producing the green compact; wherein step iii) occurs after step ii).

4. The method according to claim 3 , wherein during a production of a plurality of green compacts, step ii) is performed with a greater frequency than step c).

5. The method according to claim 1 , wherein the constant volume of the measuring device is completely filled in step c).

6. The method according to claim 1 , wherein the pressing tool comprises a control device by which a sequence and frequency of at least steps a), b), c) and d) is determined as a function of at least the following boundary conditions:
a value of the at least one determined parameter of the powdery material;
a specification for the determination;
a filling level of the powdery material in the storage container;
a time interval during which the powdery material is stored in the storage container or in the filling shoe.

7. The method according to claim 1 , wherein the at least one parameter is of the powdery material in loose un-compacted powder form.

8. The method according to claim 7 , wherein in step d) removing the powdery material from the constant volume of the measuring device via the outlet opening involves flowing the powdery material out of the outlet opening.

9. A pressing tool for producing at least one green compact, the pressing tool having at least one planar surface which is formed at least partially by a die which, starting from the surface, extends along an axial direction and, on the surface, has a cavity which extends from the surface along the axial direction and has an inner circumferential surface; wherein the cavity forms a receptacle for a powdery material which can be pressed into the green compact in the cavity by at least one punch plunging into the cavity along the axial direction; wherein a measuring device for determining a parameter of the powdery material has an opening at the surface, the opening at the surface being spaced from the cavity along a radial direction, wherein the measuring device has a constant volume directly adjoining the surface and the opening and having an outlet opening that is closeable, so that the powdery material is fillable into the volume via the opening and is dischargeable as powdery material from the volume via the outlet opening.

10. The pressing tool according to claim 9 , wherein the parameter of the powdery material is at least a flow rate or a density of the powdery material.

11. The press tool according to claim 10 , wherein the measuring device has at least a first sensor for detecting the flow rate, which detects the discharge of the powdery material via the outlet opening, or has a second sensor, which detects the weight of the powdery material located in the constant volume, so that the density can be determined therefrom.

12. The pressing tool according to claim 11 , wherein the opening is closeable by a cover.

13. The pressing tool according to claim 9 , additionally comprising a filling shoe for providing the powdery material, wherein the filling shoe is movable along the surface; wherein the filling shoe is movable over the cavity for filling the cavity and over the opening for filling the measuring device.

14. The press tool according to claim 13 , wherein the filling shoe has a starting position in which the filling shoe is fillable from a storage container for the powdery material, wherein the opening of the measuring device is arranged between the starting position and the cavity or the starting position is arranged between the cavity and the opening of the measuring device.

15. The pressing tool according to claim 13 , additionally comprising the punch movable relative to the surface along the axial direction and a control device which is set up to carry out a method including the steps of filling the filling shoe with the powdery material from a storage container; moving the filling shoe over the surface and across the opening of the measuring device; at least partially filling a constant volume of the measuring device with the powdery material from the filling shoe via the opening; and carrying out the determination of the at least one parameter of the powdery material by the measuring device and removing the powdery material from the constant volume via an outlet opening of the measuring device.

16. The pressing tool according to claim 15 , wherein the at least one parameter is of the powdery material in loose un-compacted powder form.

17. The pressing tool according to claim 16 , wherein removing the powdery material from the constant volume of the measuring device via the outlet opening the measuring device involves flowing the powdery material out of the outlet opening.

Assignees

• Gkn Sinter Metals Engineering Gmbh

Inventors

• Villgrattner Thomas
• Oberleiter Roland

Classifications

• G01F13/006

  measuring volume in function of time · CPC title

• G01F13/001

  for fluent solid material · CPC title

• G01F1/86

  Indirect mass flowmeters, e.g. measuring volume flow and density, temperature or pressure · CPC title

• B30B11/005

  Control arrangements · CPC title

• G01F15/02

  Compensating or correcting for variations in pressure, density or temperature · CPC title