Jet mill

Patent metadata

Field	Value
Publication number	US-12472506-B2
Application number	US-202118037618-A
Country	US
Kind code	B2
Filing date	Nov 18, 2021
Priority date	Nov 20, 2020
Publication date	Nov 18, 2025
Grant date	Nov 18, 2025

Abstract

The invention relates to a jet mill comprising a milling chamber with a longitudinal axis, an inlet at one end of the axis and an outlet at the opposite end of the axis, the milling chamber comprising a multitude of pins arranged in the free flow cross-section of the milling chamber, wherein the pins are arranged in at least two planes perpendicular to the longitudinal axis, the planes being distant to each other in the longitudinal direction, and the pins of one plane being laterally offset to the pins of the subsequent plane, wherein the milling chamber is divided into alternate pin segments and acceleration segments, the pin segments each having at least two planes of pins, and the acceleration segments having no pins.

First claim

The invention claimed is:

1 . A jet mill comprising a milling chamber with a longitudinal axis, an inlet at one end of the axis and an outlet at the opposite end of the axis, the milling chamber comprising a multitude of pins arranged in the free flow cross-section of the milling chamber, wherein the pins are arranged in at least two planes perpendicular to the longitudinal axis, the planes being distant to each other in the longitudinal direction, and the pins of one plane being laterally offset to the pins of the subsequent plane, wherein the milling chamber is divided into alternate pin segments and acceleration segments, the pin segments each having at least two planes of pins, and the acceleration segments having no pins, wherein the length of the acceleration segments is larger than the longitudinal distance between neighboring planes in the pin segments.

2 . The jet mill according to claim 1 , wherein the surface of the pins facing the inlet is convex.

3 . The jet mill according to claim 1 , wherein the pins are removably attached inside the milling chamber.

4 . The jet mill according to claim 1 , wherein at least some of the pins comprise a sensor capable of detecting a measure for abrasion of the respective pin.

5 . The jet mill according to claim 1 , wherein the pin segments each have two to five planes of pins.

6 . The jet mill according to claim 1 , wherein an acceleration chamber with an inlet and an outlet is connected to the milling chamber, the outlet of the acceleration chamber being the inlet of the milling chamber.

7 . The jet mill according to claim 6 , wherein the inlet of the acceleration chamber has a smaller cross-sectional area than its outlet.

8 . The jet mill according to claim 1 , wherein the height of the milling chamber is from 3 mm to 10 mm.

9 . The jet mill according to claim 1 , wherein the pins are made from a material selected from the group of wear resistant steel or wear resistant ceramics.

10 . The jet mill according to claim 1 , wherein the outlet of the milling chamber is coupled to the inlet of a classifier capable of separating fine particles from coarse particles.

11 . The jet mill according to claim 10 , wherein the outlet for the coarse fraction is recycled to the inlet of the milling chamber or to the inlet of the acceleration chamber.

12 . A process for milling solid particles comprising the steps of (a) injecting the particles in a jet, and (b) feeding the jet including the injected particles into a jet mill according to claim 1 .

13 . The process according to claim 12 , wherein the outlet of the milling chamber is coupled to the inlet of a classifier capable of separating fine particles from coarse particles, and separating at least one fine particle fraction from the classifier feed material.

Assignees

• Basf Se

Inventors

• Pikhard Oliver
• Riemann Christian

Classifications

• B02C19/061

  of the cylindrical type (B02C19/068 takes precedence) · CPC title

• B02C19/06 Primary

  Jet mills · CPC title

• B02C2210/01

  Indication of wear on beaters, knives, rollers, anvils, linings and the like · CPC title

• B02C19/0043 Primary

  the materials to be pulverised being projected against a breaking surface or breaking body by a pressurised fluid (jet mills B02C19/06) · CPC title