Stud for a doctor blade holder in a fiber web machine and doctor blade assembly for a fiber web machine

Patent metadata

Field	Value
Publication number	US-12442136-B2
Application number	US-202318370961-A
Country	US
Kind code	B2
Filing date	Sep 21, 2023
Priority date	Sep 23, 2022
Publication date	Oct 14, 2025
Grant date	Oct 14, 2025

Abstract

A plurality of studs mount a doctor blade holder to a doctor back in a fiber web machine for slidable extraction of the doctor blade holder in the cross machine direction. Each stud ( 15 ) has a body ( 16 ) with a cylindrical center segment with a protruding nonround flange ( 17 ) formed as a single piece with the center segment. Opposed flats of the nonround flange of the body ( 16 ) may be engaged by the opposed parallel jaws of a conventional wrench allowing ready attachment of the studs to the doctor blade holder and subsequent installing within the channel of a rail which is mounted to the doctor back. A slide bar may be fixed to the doctor blade holder to extend out of the rail for engagement and extraction of the doctor blade holder.

First claim

We claim:

1. A stud for attachment to a doctor blade holder in a fiber web machine, for mounting the doctor blade holder within a rail fixed to a doctor beam, the rail extending in a cross-machine direction and having a cross-machine direction extending channel; the stud comprising:
a body having an upwardly extending central section with a threaded bore and an integrally formed flange which extends outwardly from the central section, the flange being non-round for engagement by a tool, the threaded bore being configured to receive a fastener extending into a portion of the doctor blade holder to retain the doctor blade holder to the stud, such that the stud retains the doctor blade holder to the rail when inserted within the rail channel; and
a bronze cylindrical rotating piece disposed on the body to rotate about the central section.

2. The stud of claim 1 , wherein the flange of the body comprises two opposite flats.

3. The stud of claim 1 wherein the body has a circumferential shoulder at an end opposite to the flange.

4. A doctor blade assembly for a fiber web machine, the assembly comprising:
a doctor blade holder and a rail structure with a plurality of consecutive studs, wherein the doctor blade holder is arranged movable to the rail structure with a plurality of consecutive studs having a body with a flange, wherein the majority of the studs are the studs of claim 1 .

5. The assembly of claim 4 wherein the rail structure is comprised of solid metal of either bronze or stainless steel.

6. The assembly of claim 4 wherein the rail structure has an entry area with a funnel shape.

7. The assembly of claim 4 wherein the rail structure has counter bored slots which receive therein back bolts which secure the rail structure to a doctor back.

8. The assembly of claim 4 wherein the rail structure comprises two opposed rail parts spaced from one another in a machine direction perpendicular to the cross-machine direction.

9. The assembly according of claim 8 , wherein one or both of the opposed rail parts have protrusions which align with portions of the doctor back during installation to thereby control the desired position of the opposed rail parts.

10. The assembly of claim 4 , wherein the rail structure comprises a plurality of consecutive segments with interlocking structure therebetween.

11. A doctor blade assembly for a fiber web machine, the assembly comprising:
a doctor blade holder and a rail structure with a plurality of consecutive studs, wherein the doctor blade holder is arranged movable to the rail structure with a plurality of consecutive studs having a body with a flange, the rail structure for mounting the doctor blade holder within a rail fixed to a doctor beam, the rail structure extending in a cross-machine direction and having a cross-machine direction extending channel, wherein the majority of the studs comprise:
a body having an upwardly extending central section with a threaded bore and an integrally formed flange which extends outwardly from the central section, the flange being non-round for engagement by a tool, the threaded bore being configured to receive a fastener extending into a portion of the doctor blade holder to retain the doctor blade holder to the stud, such that the stud retains the doctor blade holder to the rail when inserted within the rail channel; and
wherein at one end of the rail structure there is a slide bar equipped with a handle which extends outside the rail structure.

12. The assembly of claim 11 , wherein the slide bar has several consecutive holes spaced from one another in the cross-machine direction and extending vertically and wherein a lock down bolt extends through one of the several consecutive holes to secure the cross-machine position of the doctor blade holder.

13. The assembly of claim 12 , wherein between the rail structure and the slide bar there is a transfer equipment to facilitate initial sliding movement and fine tuning of a cross-machine position of the slide bar to allow the insertion of the lock down bolt.

14. The assembly of claim 13 wherein the transfer equipment comprises:
a fork fixed to the rail structure;
a threaded block fixed to the slide bar; and
an adjustment screw extending between the fork and the threaded block and having a lock nut thereon.

15. An assembly for the removable mounting of a doctor blade to a doctor back within a fiber web machine, the assembly comprising:
a doctor blade holder having structure for retaining a doctor blade which extends in a cross-machine direction, the doctor blade holder having a plate with an underside and portions defining holes therein;
a rail structure for fixed mounting to the doctor back, the rail structure having two opposed rail parts with portions defining a channel which extends in the cross direction, the rail structure rail parts having opposed lips which extend towards one another in the machine direction into the channel, wherein each rail part has an upwardly protruding outer member positioned outwardly of the rail part's lip, each outer member having an upper surface which engages the plate underside, and each lip having a lip upper surface which is spaced below the upper surface of the rail part outer member;
a plurality of studs which connect the doctor blade holder to the rail structure and which extend downwardly into the channel of the rail structure, wherein each stud has a body with an upwardly extending central section with a top portion which extends into one of the plate holes, the central section having a threaded bore, wherein the top portion protrudes above a circumferential shoulder positioned above an integrally formed flange which extends outwardly from the central section, the flange being non-round for engagement by a tool, and a cylindrical rotating piece disposed on the body to rotate about the central section above the flange and between the lips of the rail structure, wherein the circumferential shoulder extends a first distance above the flange;
fasteners extending through the doctor blade holder plate holes into each of the threaded bores of the studs to fasten the doctor blade holder to the studs; and
wherein each rotating piece has a vertical height above the stud flange which is less than the first distance, thus a gap is defined between the rotating piece and the underside of the plate allowing the rotating piece to rotate freely.

16. The assembly of claim 15 , wherein each of the flanges of the studs comprises two opposite and parallel flats.

17. An assembly for the removable mounting of a doctor blade to a doctor back within a fiber web machine, the assembly comprising:
a doctor blade holder having structure for retaining a doctor blade which extends in a cross-machine direction;
a rail structure for fixed mounting to the doctor back, the rail structure having portions defining a channel which extends in the cross direction, the rail structure having two opposed lips which extend towards one another in the machine direction into the channel;
a plurality of studs fixed to the doctor blade holder and extending downwardly into the channel of the rail structure, wherein each stud has a body having an upwardly extending central section with a threaded bore and an integrally formed flange which extends outwardly from the central section, the flange being non-round for engagement by a tool, and a cylindrical rotating piece disposed on the body to rotate about the central section above the flange and between the lips of the rail structure;
fasteners extending through the doctor blade holder into each of the th

Assignees

• Valmet Technologies Inc

Inventors

• Lecuyer Stephane
• Olszak Jonathan

Classifications

• B31F1/14

  by doctor blades arranged crosswise to the web · CPC title

• D21G3/00

  Doctors · CPC title

• B31F1/145

  Blade constructions · CPC title

• D21G3/04

  for drying cylinders · CPC title

• D21G3/02

  for calenders · CPC title