Blade segment for refiner

Patent metadata

Field	Value
Publication number	US-12281439-B2
Application number	US-202118008625-A
Country	US
Kind code	B2
Filing date	Jun 3, 2021
Priority date	Jun 8, 2020
Publication date	Apr 22, 2025
Grant date	Apr 22, 2025

Abstract

A blade segment ( 4, 8 ) for a refiner ( 1 ) for refining fibrous material has a first ( 20 ) and a second ( 21 ) end edge and a first ( 22 ) and a second ( 23 ) side edge opposite to the first side edge ( 22 ) and a refining surface ( 5, 9 ) having blade bars ( 27, 27 a, 27 b ) and grooves ( 28, 28 a, 28 b ) therebetween on a front surface ( 25 ). At least one opening ( 14, 15 ) is on at least at one side edge ( 22, 23 ) which extends through the whole thickness of the blade segment body ( 24 ). There is at least one feed groove ( 29 ) on the refining surface, the feed groove ( 29 ) extending from the opening and crossing the blade bars and the blade grooves for feeding the material to be refined across the refining surface. The blade bars ( 27, 27 a, 27 b ) of the blade segment are interlaced at the feed groove.

First claim

The invention claimed is:

1. A blade segment for a refiner for refining fibrous material, the blade segment comprising:
a blade body having a front surface and a rear surface, defining a blade body thickness therebetween, the blade body bounded by a first end edge, a second end edge, a first side edge, and a second side edge opposite to the first side edge, the first side edge and the second side edge extending between the first end edge and the second end edge, wherein the front surface has blade bars and blade grooves which together form a refining surface of the blade segment;
portions of the blade body forming at least one opening extending through the blade body thickness from the front surface to the rear surface and adjoining at least at one of the first side edge and the second side edge when the segment is mounted within a refiner alongside another segment;
at least one feed groove on the refining surface, the feed groove extending from the at least one opening and crossing the blade bars and the blade grooves for feeding the material to be refined across the refining surface; and
wherein the blade bars of the blade segment are interlaced at the feed groove.

2. The blade segment of claim 1 wherein the at least one opening extending through the blade body thickness is a continuous slit along the first side edge when an adjoining blade segment engages extensions arranged at a first corner of the blade segment where the first end edge joins the first side edge, and at a second corner of the blade segment where the second end edge joins the first side edge.

3. The blade segment of claim 1 wherein the opening is an indent in one of the first and second side edges and extending towards the other of the first side edge and the second side edge.

4. The blade segment of claim 1 wherein the blade bars have end parts which are interlaced at the feed groove, the end parts extending into opposed ones of the blade grooves, such that every other one of the end parts is directed into one of the blade grooves on an opposite side of the feed groove.

5. The blade segment of claim 4 wherein the end parts of the interlaced blade bars comprise downwards descending sloping ends arranged to form the upwardly opening feed groove.

6. The blade segment of claim 5 wherein the end parts of the interlaced blade bars are linearly downwards sloping ends arranged to form the feed groove as an upwards opening V-shaped groove.

7. The blade segment of claim 5 wherein a cross-sectional area of the feed groove decreases from the at least one opening, as the feed groove extends across the blade bars and the blade grooves.

8. The blade segment of claim 7 wherein an angle of the downwards descending sloping ends of the blade bars relative to a normal of the refining surface at the feed groove is arranged to decrease along the feed groove from a first end of the feed groove closest to the at least one opening towards a second end of the feed groove farther away from the at least one opening.

9. The blade segment of claim 7 wherein angles of the downwards descending sloping ends of the blade bars relative to a normal of the refining surface at the feed groove are equal.

10. The blade segment of claim 7 wherein a vertical position of a plane of incidence of the interlaced downwards descending sloping ends of the interlaced blade bars is substantially constant along the feed groove.

11. The blade segment of claim 1 wherein the feed groove is arranged to cross the blade bars and the blade grooves at an angle.

12. The blade segment of claim 11 wherein the feed groove is arranged to cross the blade bars and the blade grooves at an angle of 90±45 degrees.

13. The blade segment of claim 1 wherein the feed groove is curved along its direction of extension.

14. A refiner for refining fibrous material comprising a plurality of blade segments, the plurality of segments comprising:
a first blade segment mounted within the refiner alongside a second blade segment;
wherein the first segment comprises:
a blade body having a front surface and a rear surface defining a blade body thickness therebetween, the blade body bounded by a first end edge, a second end edge, a first side edge, and a second side edge opposite to the first side edge, the first side edge and the second side edge extending between the first end edge and the second end edge, wherein the front surface has blade bars and blade grooves which together form a refining surface of the first blade segment;
portions of the blade body forming a first opening alongside the second blade segment, the first opening extending through the blade body thickness from the front side to the rear side and adjoining the first side edge of the first blade segment;
at least one feed groove on the refining surface, the feed groove extending from the first opening and crossing the blade bars and the blade grooves for feeding the material to be refined across the refining surface;
wherein the blade bars and blade grooves extend from the first end edge toward the second end edge, and the blade bars alternate with blade grooves between the first side edge and the second side edge;
wherein the blade bars on one side of the feed groove transition into blade grooves on a second opposed side of the feed groove as they cross the feed groove, and the blade grooves on the one side of the feed groove transition into blade bars on the second opposed side of the feed groove; and
wherein the blade bars outside the feed groove have a first height, and the blade grooves have a second height below the first height, and the blade bars are partly interlaced at the feed groove such that at a midline of the feed groove all the blade bars have a height between the first height and the second height.

15. The refiner of claim 14 wherein at the feed groove the blade bars comprise downwards descending sloping ends, and the blade grooves comprise upwards ascending sloping ends arranged to form the feed groove opening upwardly.

16. The refiner of claim 15 wherein at the feed groove the blade bars comprise linearly downwards descending sloping ends, and the blade grooves comprise linearly upwards ascending sloping ends arranged to form the feed groove as an upwards opening V-shaped groove.

17. The refiner of claim 14 wherein a cross-sectional area of the feed groove decreases from the opening as the feed groove extends across the blade bars and the blade grooves.

18. The refiner of claim 14 wherein the blade bars have end parts which comprise downwards descending sloping ends which extend across the midline, and wherein the end parts of the blade bars on the one side of the feed groove are joined to opposed end parts of the blade bars on the second opposed side of the feed groove.

19. A blade segment for a refiner for refining fibrous material, the blade segment comprising:
a blade body having a front surface and a rear surface defining a blade body thickness therebetween, wherein the blade body is bounded by a first end edge, a second end edge, a first side edge and a second side edge opposite to the first side edge, the first side edge and the second side edge extending between the first end edge and the second end edge, wherein the front surface has blade bars and blade grooves which together form a refining surface of the blade segment;
portions of the blade body forming, when positioned alongside a second blade segment, a first opening extending through the blade body thickness from the front side to the rear side and adjoining at least one of the first

Assignees

• Valmet Technologies Oy

Inventors

• Loijas Marko
• Iisakkila Tomi

Classifications

• D21D1/24 Primary

  Jordan rolls · CPC title

• D21D1/306 Primary

  Discs · CPC title