US3649991A - Doctors for paper making machines - Google Patents

Doctors for paper making machines Download PDF

Info

Publication number
US3649991A
US3649991A US861409A US3649991DA US3649991A US 3649991 A US3649991 A US 3649991A US 861409 A US861409 A US 861409A US 3649991D A US3649991D A US 3649991DA US 3649991 A US3649991 A US 3649991A
Authority
US
United States
Prior art keywords
holder
pressure
plate
blade
edge
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US861409A
Other languages
English (en)
Inventor
Roger Anthony Grimston
Albert Henry John Boyland
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Vlckerys Ltd
Original Assignee
Vlckerys Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Vlckerys Ltd filed Critical Vlckerys Ltd
Application granted granted Critical
Publication of US3649991A publication Critical patent/US3649991A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • D—TEXTILES; PAPER
    • D21—PAPER-MAKING; PRODUCTION OF CELLULOSE
    • D21G—CALENDERS; ACCESSORIES FOR PAPER-MAKING MACHINES
    • D21G3/00—Doctors
    • D21G3/005—Doctor knifes

Definitions

  • ABSTRACT Primary Examiner-Leon G. Machlin Attorney-Watson, Cole, Grindle & Watson [5 7] ABSTRACT
  • the invention provides a doctor for a paper making machine in which the holder for the doctor blade carries a series of spaced members which are individually adjustable, without any distortion of the blade holder itself, to vary the doctoring pressure applied by the blade at different zones along its length.
  • PATENTEDMARZI m2 SHEET 2 [IF 2 Q l I DOCTORS FOR PAPER MAKING MACHINES it is essential that the doctor blade should be in even contact with the roll surface over its whole length. Furthermore, it is desirable that the contact pressure should not vary unduly along the roll face.
  • Some rolls are cambered, that is to say the diameter increases from the ends towards the center.
  • Other rolls, and particularly cylinders, are heated with the result that the diameter tends to increase unevenly as the cylinder expands.
  • the roll may deflect under its own weight since it is only supported at the ends.
  • the doctor support has uneven surfaces and/or deflects in the center. All .these factors militate against a consistent doctor blade contact pressure along the whole length of the roll.
  • the invention provides a doctor for a papermaking machine in which the holder for the doctor blade carries a series of spaced members which are individually adjustable, without any distortion of the blade holder itself, to vary the doctoring pressure applied by the blade at different zones along its length.
  • the blade holder may carry a series of spaced adjusting screws which are individually adjustable to effect variation of the level at different points along its length either of the rear end of the doctor blade itself or of the rear end of a pressure plate, mounted in the blade holder, which applies pressure to the doctor blade.
  • FIG. 1 is a perspective view of part of one form of doctor according to the invention
  • FIG. 2 is a cross-sectional view of the doctor shown in FIG. I.
  • FIGS. 3-6 are cross-sectional views similar to that of FIG. 2 showing alternative forms of doctor.
  • the doctor includes a doctor blade 10, a pressure plate 11, and a blade holder made of two parts 12, 13 suitably secured together.
  • Screws 14 are screwed at intervals, for example of 3 inches, into the upper part 12 of the blade holder and have at their lower ends heads 15, accommodated in a recess 16 in the lower part 13, which bear against the undersurface of the rear end of the pressure plate 11.
  • the screws 14 are individually adjustable and when any screw is raised it will cause the adjacent portion of the pressure plate 11 to rock about the nose 17 of the blade holder to increase the local pressure applied by the pressure plate to the doctor blade and therefore the doctoring pressure applied to the roll 18.
  • the screws 14 are provided with any convenient form of thread lock to ensure their retention in adjusted position, e.g., a longitudinal strip of nylon inserted into the threads which will ensure firm engagement with the corresponding threads in the blade holder.
  • FIG. 4 shows a very similar construction, the screws 14 again being fitted into the lower part of the blade holder, but in this case the screws bear against the undersurface of the pressure plate 11.
  • the screws can engage a deforma le bar 20 extending longitudinally of the doctor and interposed between the screws 14 and the pressure plate 13.
  • the deformable bar may be arranged to bear against the doctor blade. Such a deformable bar provides for more even distribution of the distortion of the blade 10 resulting from adjustment of the screws 14.
  • FIG. 6 shows a doctor in which, as described in U.S. application No. 728,727, now U.S. Pat. No. 3,596,305, issued Aug. 3, 1971, the pressure plate 11 applies pressure to the side of the doctor blade 10 facing the roll and the screws 14 bear against the upper surface of the pressure plate.
  • Structure for doctoring a roll of a papermaking machine comprising:
  • an elongated, generally planar doctor blade having a Iongitudinally extending face and a longitudinal doctoring edge disposed generally in line contact with said roll;
  • an elongated, generally planar pressure plate having a longitudinally extending face and a longitudinal pressure edge disposed generally in line contact with the face of the blade;
  • a holder for the blade and the plate said holder having an elongated abutment nose presenting a longitudinally extending fulcrum edge disposed generally in line contact with the face of the plate, said plate having a rear edge spaced from the pressure edge, said fulcrum edge contacting the plate at a location intermediate the rear edge and pressure edge thereof;
  • a doctor for a roll of a papennaking machine comprising a blade holder, a doctor blade accommodated in said holder for pivotal movement about its rear end with respect to the holder and adapted to bear at its front end against said roll, a pressure plate accommodated in the holder for pivotal movement about a nose on the holder which bears against the pressure plate at a location intermediate its front and rear ends, said pressure plate bearing at its front end against the doctor blade to press said doctor blade against the roll, and a plurality of spaced adjusting members on said holder disposed to bear against the rear end of said pressure plate, said adjusting members being individually adjustable to cause pivotal movement of adjacent parts of the pressure plate about said nose and thereby to effect variations in the pressure applied by the pressure plate to the doctor blade at different points along its length and consequent variation in the doctoring pressure applied to the roll.
  • a doctor as claimed in claim 4 which includes a deformable longitudinal bar disposed within the blade holder and interposed between the adjusting members and the rear end of the pressure plate.

Landscapes

  • Paper (AREA)
US861409A 1968-10-01 1969-09-26 Doctors for paper making machines Expired - Lifetime US3649991A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB4658868 1968-10-01

Publications (1)

Publication Number Publication Date
US3649991A true US3649991A (en) 1972-03-21

Family

ID=10441846

Family Applications (1)

Application Number Title Priority Date Filing Date
US861409A Expired - Lifetime US3649991A (en) 1968-10-01 1969-09-26 Doctors for paper making machines

Country Status (5)

Country Link
US (1) US3649991A (enrdf_load_stackoverflow)
BR (1) BR6912871D0 (enrdf_load_stackoverflow)
DE (1) DE1948112A1 (enrdf_load_stackoverflow)
GB (1) GB1226160A (enrdf_load_stackoverflow)
SE (1) SE359875B (enrdf_load_stackoverflow)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3884145A (en) * 1972-09-19 1975-05-20 Daetwyler & Co M Doctor blade for photogravure printing machine
US4803752A (en) * 1982-08-23 1989-02-14 Canon Kabushiki Kaisha Cleaning device
US5279710A (en) * 1988-11-16 1994-01-18 Aikawa Iron Works, Co., Ltd. Doctor blade supporting structure
CN109675871A (zh) * 2018-12-26 2019-04-26 江苏理文造纸有限公司 一种纸机的烘缸缸面清洁机构
US12226062B1 (en) * 2023-01-11 2025-02-18 Transition Automation, Inc. Squeegee holder with an integrated clamp bar

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4151797A (en) * 1977-05-04 1979-05-01 Mid America Tag And Label Company, Inc. Doctor blade apparatus
US5230775A (en) * 1990-06-05 1993-07-27 Thermo Electron Web Systems, Inc. Blade edge loading control for doctoring apparatus
DE9214884U1 (de) * 1992-10-28 1994-03-03 Zimmer, Johannes, Klagenfurt Rakeleinrichtung

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US767933A (en) * 1903-11-27 1904-08-16 Joseph Lawrence Galleciez Guard-board.
US1803927A (en) * 1930-09-26 1931-05-05 Rice Barton & Fales Inc Flexible doctor or scraper blade
US2477339A (en) * 1945-02-14 1949-07-26 Lodding Engineering Corp Doctor mechanism for rolls and cylinders
GB656812A (en) * 1947-11-12 1951-09-05 Gen Am Transport Scraper blade
US2664792A (en) * 1949-09-27 1954-01-05 Brown Co Multilength continuous doctor blade

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US767933A (en) * 1903-11-27 1904-08-16 Joseph Lawrence Galleciez Guard-board.
US1803927A (en) * 1930-09-26 1931-05-05 Rice Barton & Fales Inc Flexible doctor or scraper blade
US2477339A (en) * 1945-02-14 1949-07-26 Lodding Engineering Corp Doctor mechanism for rolls and cylinders
GB656812A (en) * 1947-11-12 1951-09-05 Gen Am Transport Scraper blade
US2664792A (en) * 1949-09-27 1954-01-05 Brown Co Multilength continuous doctor blade

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3884145A (en) * 1972-09-19 1975-05-20 Daetwyler & Co M Doctor blade for photogravure printing machine
US4803752A (en) * 1982-08-23 1989-02-14 Canon Kabushiki Kaisha Cleaning device
US5279710A (en) * 1988-11-16 1994-01-18 Aikawa Iron Works, Co., Ltd. Doctor blade supporting structure
CN109675871A (zh) * 2018-12-26 2019-04-26 江苏理文造纸有限公司 一种纸机的烘缸缸面清洁机构
CN109675871B (zh) * 2018-12-26 2021-06-18 江苏理文造纸有限公司 一种纸机的烘缸缸面清洁机构
US12226062B1 (en) * 2023-01-11 2025-02-18 Transition Automation, Inc. Squeegee holder with an integrated clamp bar

Also Published As

Publication number Publication date
SE359875B (enrdf_load_stackoverflow) 1973-09-10
BR6912871D0 (pt) 1973-01-09
DE1948112A1 (de) 1970-04-09
GB1226160A (enrdf_load_stackoverflow) 1971-03-24

Similar Documents

Publication Publication Date Title
US2914788A (en) Doctor knives
US3649991A (en) Doctors for paper making machines
US2477339A (en) Doctor mechanism for rolls and cylinders
US3866266A (en) Self-adjusting doctor blades
US2611150A (en) Apparatus and method for performing sheeting or coating operations on or with plastic material
SE7711781L (sv) Fergbehallare for offset- och hogtrycksmaskiner
US5061347A (en) Adjustable ledge for the sheet forming zone of a papermaking machine
US3163878A (en) Doctor knives
US4076864A (en) Method and apparatus for coating both sides of a moving web
US4192709A (en) Creping doctor
US2718827A (en) Paper calender
ES2110153T3 (es) Disposicion de entintado para prensas de impresion.
US4141112A (en) Doctors for paper-making machines
US1883167A (en) Doctor for paper-making machinery
US2205564A (en) Art of slitting flexible material
US1803927A (en) Flexible doctor or scraper blade
US3180251A (en) Calenders
US2293666A (en) Take-up mechanism for looms
US2487409A (en) Doctor blade and mounting
US2073308A (en) Printing die and retaining means therefor
US2110216A (en) Dual purpose distributing system for rotary offset and lithographic presses
US2900674A (en) Pressure-applying means for drafting roll
GB1596562A (en) Creping doctor
SE9102623D0 (sv) Kalander foer pappers- eller kartongmaskin
US1934495A (en) Loom temple