WO1996029139A1 - Self-cleaning filter for pneumatic circuits - Google Patents

Self-cleaning filter for pneumatic circuits Download PDF

Info

Publication number
WO1996029139A1
WO1996029139A1 PCT/IT1996/000048 IT9600048W WO9629139A1 WO 1996029139 A1 WO1996029139 A1 WO 1996029139A1 IT 9600048 W IT9600048 W IT 9600048W WO 9629139 A1 WO9629139 A1 WO 9629139A1
Authority
WO
WIPO (PCT)
Prior art keywords
baffle
mouth
nozzle
self
cleaning filter
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.)
Ceased
Application number
PCT/IT1996/000048
Other languages
French (fr)
Inventor
Eros Nani
Andrea Bonandrini
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.)
Mazzini ICI SpA
Original Assignee
Mazzini ICI SpA
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 Mazzini ICI SpA filed Critical Mazzini ICI SpA
Priority to AU49530/96A priority Critical patent/AU4953096A/en
Priority to US08/913,382 priority patent/US5958093A/en
Priority to JP8528241A priority patent/JPH11502762A/en
Priority to DK96905989T priority patent/DK0814892T3/en
Priority to BR9607684-4A priority patent/BR9607684A/en
Priority to EP96905989A priority patent/EP0814892B1/en
Priority to DE69604573T priority patent/DE69604573T2/en
Publication of WO1996029139A1 publication Critical patent/WO1996029139A1/en
Anticipated expiration legal-status Critical
Priority to GR990402650T priority patent/GR3031556T3/en
Ceased legal-status Critical Current

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D46/00—Filters or filtering processes specially modified for separating dispersed particles from gases or vapours
    • B01D46/24—Particle separators, e.g. dust precipitators, using rigid hollow filter bodies
    • B01D46/2403—Particle separators, e.g. dust precipitators, using rigid hollow filter bodies characterised by the physical shape or structure of the filtering element
    • B01D46/2411—Filter cartridges
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D46/00—Filters or filtering processes specially modified for separating dispersed particles from gases or vapours
    • B01D46/0052—Filters or filtering processes specially modified for separating dispersed particles from gases or vapours with filtering elements moving during filtering operation
    • B01D46/0056—Filters or filtering processes specially modified for separating dispersed particles from gases or vapours with filtering elements moving during filtering operation with rotational movement
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D46/00—Filters or filtering processes specially modified for separating dispersed particles from gases or vapours
    • B01D46/52—Particle separators, e.g. dust precipitators, using filters embodying folded corrugated or wound sheet material
    • B01D46/521—Particle separators, e.g. dust precipitators, using filters embodying folded corrugated or wound sheet material using folded, pleated material
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D46/00—Filters or filtering processes specially modified for separating dispersed particles from gases or vapours
    • B01D46/66—Regeneration of the filtering material or filter elements inside the filter
    • B01D46/70—Regeneration of the filtering material or filter elements inside the filter by acting counter-currently on the filtering surface, e.g. by flushing on the non-cake side of the filter
    • B01D46/71—Regeneration of the filtering material or filter elements inside the filter by acting counter-currently on the filtering surface, e.g. by flushing on the non-cake side of the filter with pressurised gas, e.g. pulsed air
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D2273/00—Operation of filters specially adapted for separating dispersed particles from gases or vapours
    • B01D2273/28—Making use of vacuum or underpressure

Definitions

  • the present invention relates to filters used in pneumatic circuits, and in particular to a self-cleaning filter intended mainly, but not exclusively, for filtering air.
  • a blowing nozzle possibly rotating, which is usually located inside the drum.
  • This nozzle intermittently emits a strong jet of compressed air which causes the dust to fall on the bottom of the filter case thanks to the counter-pressure.
  • Such a cleaning system is based on the instantaneous shaking and on the temporary inversion of direction of the air flow through the baffle, however it has a limited effectiveness too. In fact, first of all it can not be applied in a continuous way since it momentarily blocks the incoming air flow. Moreover, its action is not localized but general, whereby it is not particularly effective at the bottom of the baffle pleats where the suction mouth does not arrive.
  • the object of the present invention is to provide a self- cleaning filter suitable to overcome the drawbacks of prior art filters. This object is achieved by means of a filter having the characteristics cited in claim 1.
  • the main advantage of the filter according to the present invention is its capacity of complete self-regeneration even in the remotest areas at the bottom of the filtering baffle pleats.
  • FiQ.1 is a schematic front view of a filter according to the invention
  • Fi ⁇ .2 is a schematic partially sectional side view of the filter of fig.1
  • Fiq.3 is an enlargement of portion R of f ⁇ g.2.
  • a self-cleaning filter includes a filtering baffle 1 mounted on a drum 2 which is rotated steadily by a motor-reducer 3 through a friction pulley which acts on the inner surface of drum 2.
  • the outer surface of friction 2 also has a rib which engages with corresponding guide rollers 4.
  • a suction mouth 5 is longitudinally positioned in the vertical mid- plane outside the filtering baffle 1 , at the lowest point of the baffle and adjacent thereto.
  • a blowing nozzle 6 is located at an exactly opposite position inside the filtering baffle 1. As better seen in the enlarged view of fig.3, both the suction mouth 5 and the blowing nozzle 6 extend along the whole length of the filtering baffle 1.
  • nozzle 6 has a "flute" structure, i.e. a plurality of bores aligned along the whole length of baffle 1 , suitable to emit a narrow jet of air.
  • mouth 5 is shaped as a trapezoidal hopper with the suction duct at its lowest end.
  • a small adjustable blowing nozzle C is located at the opposite end of mouth 5.
  • the air flow to be filtered passes through baffle 1 from outside to inside, as indicated by arrow A in fig.2.
  • the mouth 5 isolates a small portion of the filtering baffle 1 and sucks up therefrom the material deposited on the outer surface, which is gathered in the hopper and removed by the suction flow B.
  • the small nozzle C intermittently acts with an oriented jet which helps the removal of the material.
  • the complete regeneration of the filtering baffle 1 is achieved through the timed action of the inner blowing nozzle 6 with a flow D of counter-current compressed air.
  • the air blade which comes from nozzle 6 removes the dust from the bottom of the pleats and conveys it to mouth 5.
  • nozzle 6 preferably has an adjustable incidence in order to generate vibrations on baffle 1 which facilitate the dust removal.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Physics & Mathematics (AREA)
  • Geometry (AREA)
  • Filtering Of Dispersed Particles In Gases (AREA)
  • Fluid-Pressure Circuits (AREA)
  • Electrical Discharge Machining, Electrochemical Machining, And Combined Machining (AREA)
  • Spinning Or Twisting Of Yarns (AREA)
  • Preliminary Treatment Of Fibers (AREA)
  • Filtration Of Liquid (AREA)

Abstract

A self-cleaning filter for pneumatic circuits includes a filtering baffle (1) mounted on a drum (2) rotated steadily, the flow (A) of the air to be filtered being from outside to inside the baffle (1), as well as a suction mouth (5) longitudinally positioned in the vertical mid-plane at the lowest point of the baffle (1) and externally adjacent thereto, and a blowing nozzle (6) internally adjacent to the baffle (1) at a position exactly opposite the mouth (5), both the mouth (5) and the nozzle (6) extending along the whole length of the filtering baffle (1). The nozzle (6) has a plurality of aligned bores suitable to emit a narrow jet of counter-current air, with adjustable incidence, and the mouth (5) is shaped as a trapezoidal hopper with a small adjustable blowing nozzle (C) at one end.

Description

"SELF-CLEANING FILTER FOR PNEUMATIC CIRCUITS"
The present invention relates to filters used in pneumatic circuits, and in particular to a self-cleaning filter intended mainly, but not exclusively, for filtering air.
It is known that various industrial plants use air to drain away processing wastes and/or for different kinds of treatments, and they include devices for filtering the air polluted by particles or substances of various origin. Reference will be made hereafter to filters employed in particular in the textile industries plants, being clear that the following is valid also for other similar applications.
It is known that conventional self-cleaning filters essentially consist of a drum housed in a case and covered with a continuous filtering baffle. This drum is provided with a relative motion with respect to a suction mouth located on the air inlet side and/or with respect to a blowing nozzle located on the opposite side. The relative motion is usually achieved by rotating the drum around mouths which are fixed or longitudinally shifting at most. Obviously, it is also possible to keep the drum still and rotate/shift the mouths. The function of the suction mouth on the air inlet side is to suck up dust, wastes, etc. which deposit on said side of the filtering baffle. However, the effectiveness of said mouth is good only in case the filtering baffle is flat, so that the mouth can be positioned close to the baffle. On the contrary, in the most common case of pleated baffle (which increases the filtering surface with the same bulkiness) the bottom areas of the pleats are not adequately cleaned, thus reducing the advantage coming from the pleating.
In this case, in order to improve the baffle cleaning there is adopted a blowing nozzle, possibly rotating, which is usually located inside the drum. This nozzle intermittently emits a strong jet of compressed air which causes the dust to fall on the bottom of the filter case thanks to the counter-pressure. Such a cleaning system is based on the instantaneous shaking and on the temporary inversion of direction of the air flow through the baffle, however it has a limited effectiveness too. In fact, first of all it can not be applied in a continuous way since it momentarily blocks the incoming air flow. Moreover, its action is not localized but general, whereby it is not particularly effective at the bottom of the baffle pleats where the suction mouth does not arrive.
Therefore the object of the present invention is to provide a self- cleaning filter suitable to overcome the drawbacks of prior art filters. This object is achieved by means of a filter having the characteristics cited in claim 1.
The main advantage of the filter according to the present invention is its capacity of complete self-regeneration even in the remotest areas at the bottom of the filtering baffle pleats. This and other advantages and characteristics of the self-cleaning filter according to the present invention will be clear to those skilled in the art from the following detailed description of an embodiment thereof, with reference to the annexed drawings wherein:
FiQ.1 is a schematic front view of a filter according to the invention; Fiα.2 is a schematic partially sectional side view of the filter of fig.1; and
Fiq.3 is an enlargement of portion R of fιg.2.
Referring to figs.1 and 2, there is seen that a self-cleaning filter according to the present invention includes a filtering baffle 1 mounted on a drum 2 which is rotated steadily by a motor-reducer 3 through a friction pulley which acts on the inner surface of drum 2. The outer surface of friction 2 also has a rib which engages with corresponding guide rollers 4.
A suction mouth 5 is longitudinally positioned in the vertical mid- plane outside the filtering baffle 1 , at the lowest point of the baffle and adjacent thereto. A blowing nozzle 6 is located at an exactly opposite position inside the filtering baffle 1. As better seen in the enlarged view of fig.3, both the suction mouth 5 and the blowing nozzle 6 extend along the whole length of the filtering baffle 1. In particular, nozzle 6 has a "flute" structure, i.e. a plurality of bores aligned along the whole length of baffle 1 , suitable to emit a narrow jet of air. On the other hand, mouth 5 is shaped as a trapezoidal hopper with the suction duct at its lowest end. A small adjustable blowing nozzle C is located at the opposite end of mouth 5.
The air flow to be filtered passes through baffle 1 from outside to inside, as indicated by arrow A in fig.2. The mouth 5 isolates a small portion of the filtering baffle 1 and sucks up therefrom the material deposited on the outer surface, which is gathered in the hopper and removed by the suction flow B. In order to improve the effectiveness of said cleaning, especially in case of damp and/or adhesive dusts, the small nozzle C intermittently acts with an oriented jet which helps the removal of the material.
The complete regeneration of the filtering baffle 1 is achieved through the timed action of the inner blowing nozzle 6 with a flow D of counter-current compressed air. The air blade which comes from nozzle 6 removes the dust from the bottom of the pleats and conveys it to mouth 5. Furthermore, nozzle 6 preferably has an adjustable incidence in order to generate vibrations on baffle 1 which facilitate the dust removal.
Thanks to the localized nature of the jet, and since also nozzle 6 is placed adjacent to the filtering baffle 1 and at the suction mouth 5, said counter-current jet does not interfere with the normal flow A of the incoming air. Therefore, it is possible to regenerate deeply the filtering baffle 1 even when it is of the pleated type, without disturbing the normal operation of the filter.
It is clear that the above-described and illustrated embodiment of the self-cleaning filter according to the invention is just an example susceptible of various modifications. In particular, the exact shape of mouth 5 and nozzle 6 can be freely adapted according to specific needs, as long as their mutual position and with respect to the filtering baffle 1 , as well as their length equal to the baffle length, are maintained.

Claims

1. A self-cleaning filter for pneumatic circuits, including a filtering baffle (1 ) mounted on a drum (2) rotated steadily, as well as a suction mouth (5) located outside the baffle (1 ) and a blowing nozzle (6) located inside, the flow (A) of the air to be filtered being from outside to inside the baffle (1 ), characterized in that said suction mouth (5) is longitudinally positioned in the vertical mid-plane at the lowest point of the baffle (1) and adjacent thereto and also the blowing nozzle (6) is adjacent to the baffle (1 ) at a position exactly opposite the mouth (5), both the mouth (5) and the nozzle (6) extending along the whole length of the filtering baffle (1 ).
2. A self-cleaning filter according to claim 1 , characterized in that the nozzle (6) has a plurality of aligned bores along the whole length of the baffle (1 ), the incidence of the nozzle (6) being adjustable.
3. A self-cleaning filter according to claim 1 or 2, characterized in that the mouth (5) is shaped as a trapezoidal hopper, with a suction duct at the lowest end and a small adjustable blowing nozzle (C) located at the opposite end.
PCT/IT1996/000048 1995-03-20 1996-03-15 Self-cleaning filter for pneumatic circuits Ceased WO1996029139A1 (en)

Priority Applications (8)

Application Number Priority Date Filing Date Title
AU49530/96A AU4953096A (en) 1995-03-20 1996-03-15 Self-cleaning filter for pneumatic circuits
US08/913,382 US5958093A (en) 1995-03-20 1996-03-15 Self-cleaning filter for pneumatic circuits
JP8528241A JPH11502762A (en) 1995-03-20 1996-03-15 Air circuit self-cleaning filter
DK96905989T DK0814892T3 (en) 1995-03-20 1996-03-15 Self-cleaning filter for pneumatic circuits
BR9607684-4A BR9607684A (en) 1995-03-20 1996-03-15 Self-cleaning filter for pneumatic circuits
EP96905989A EP0814892B1 (en) 1995-03-20 1996-03-15 Self-cleaning filter for pneumatic circuits
DE69604573T DE69604573T2 (en) 1995-03-20 1996-03-15 SELF-CLEANING FILTER FOR PNEUMATIC CIRCUIT
GR990402650T GR3031556T3 (en) 1995-03-20 1999-10-15 Self-cleaning filter for pneumatic circuits

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
IT95MI000546A IT1277170B1 (en) 1995-03-20 1995-03-20 SELF-CLEANING FILTER FOR PNEUMATIC CIRCUITS
ITMI95A000546 1995-03-20

Publications (1)

Publication Number Publication Date
WO1996029139A1 true WO1996029139A1 (en) 1996-09-26

Family

ID=11370973

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/IT1996/000048 Ceased WO1996029139A1 (en) 1995-03-20 1996-03-15 Self-cleaning filter for pneumatic circuits

Country Status (12)

Country Link
US (1) US5958093A (en)
EP (1) EP0814892B1 (en)
JP (1) JPH11502762A (en)
AT (1) ATE185283T1 (en)
AU (1) AU4953096A (en)
BR (1) BR9607684A (en)
DE (1) DE69604573T2 (en)
DK (1) DK0814892T3 (en)
ES (1) ES2138326T3 (en)
GR (1) GR3031556T3 (en)
IT (1) IT1277170B1 (en)
WO (1) WO1996029139A1 (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2112951A4 (en) * 2006-08-21 2010-05-05 Stuart Cole Apparatus for cleaning cylindrical air filters
EP2320071A3 (en) * 2009-11-05 2014-02-12 General Electric Company Active flow control system for wind turbine

Families Citing this family (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE10347691A1 (en) * 2003-10-14 2005-05-19 Sohler-Neuenhauser Gmbh & Co. Kg Cleaning device for textile machines
US7264422B2 (en) * 2004-03-25 2007-09-04 Owens-Corning Fiberglas Technology Inc. Rotary separator for mineral fibers
GB0513138D0 (en) * 2005-06-29 2005-08-03 Impact Air Systems Ltd Filtration
KR100770181B1 (en) * 2006-07-31 2007-10-25 주식회사 포스코 Multifunctional Baffle Damping Device Adopted Bag Filter Dust Collector
EP2399498A1 (en) 2010-06-22 2011-12-28 Koninklijke Philips Electronics N.V. Device for purifying a fluid
JP6094926B2 (en) * 2013-03-21 2017-03-15 株式会社流機エンジニアリング Dust collector
US10371106B2 (en) 2017-03-24 2019-08-06 Cnh Industrial America Llc Blow-out rotary screen cleaner
US11065941B1 (en) 2018-08-31 2021-07-20 Maradyne Corporation Vehicle air filter

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB191102736A (en) * 1911-02-02 1911-08-10 Hubert Winkler Improvements in Air-filters.
FR687742A (en) * 1929-02-01 1930-08-12 Filtering method and device for removing dust from gases, air, etc.
FR1169435A (en) * 1956-12-03 1958-12-29 Fram Corp Apparatus for cleaning annular filter elements
US4253855A (en) * 1979-02-26 1981-03-03 Horn And Gladden Lint Cleaner Air filter
US4826512A (en) * 1988-10-19 1989-05-02 Fuller Carmel U Self-cleaning air filter
US4830642A (en) * 1988-02-19 1989-05-16 Cv International, Inc. Filter system with in situ cleaning of an operating filter unit
EP0389045A2 (en) * 1989-03-22 1990-09-26 Airtec Di Grieco Annamaria Filtering device for separating dust from aeriform fluid and in particular for separating textile dust

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US2500747A (en) * 1946-01-05 1950-03-14 Robert P Ellis Dust separating and collecting machine
US3345805A (en) * 1966-09-01 1967-10-10 Microtron Corp Apparatus for cleaning filters
US3483675A (en) * 1967-01-12 1969-12-16 Bahnson Co Automatic cleaning filtering apparatus
US3472002A (en) * 1967-02-09 1969-10-14 North American Rockwell Self-cleaning drum type filter assembly
US3499267A (en) * 1968-08-20 1970-03-10 Bahnson Co Cleaning apparatus for rotary drum filters
US3606735A (en) * 1969-07-01 1971-09-21 Aeronca Inc Air filter assembly providing increased filtering surface area for a given volumetric size
US3667195A (en) * 1970-03-16 1972-06-06 Grinnell Corp Rotary air filter cleaning apparatus
US4222754A (en) * 1978-11-24 1980-09-16 Horvat Ivan J High efficiency filter for textile waste
US4481021A (en) * 1983-01-20 1984-11-06 United Air Filter Company Rotary drum air filter
US4842624A (en) * 1988-05-19 1989-06-27 Barton Ronald R Apparatus for cleaning air filters

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB191102736A (en) * 1911-02-02 1911-08-10 Hubert Winkler Improvements in Air-filters.
FR687742A (en) * 1929-02-01 1930-08-12 Filtering method and device for removing dust from gases, air, etc.
FR1169435A (en) * 1956-12-03 1958-12-29 Fram Corp Apparatus for cleaning annular filter elements
US4253855A (en) * 1979-02-26 1981-03-03 Horn And Gladden Lint Cleaner Air filter
US4830642A (en) * 1988-02-19 1989-05-16 Cv International, Inc. Filter system with in situ cleaning of an operating filter unit
US4826512A (en) * 1988-10-19 1989-05-02 Fuller Carmel U Self-cleaning air filter
EP0389045A2 (en) * 1989-03-22 1990-09-26 Airtec Di Grieco Annamaria Filtering device for separating dust from aeriform fluid and in particular for separating textile dust

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2112951A4 (en) * 2006-08-21 2010-05-05 Stuart Cole Apparatus for cleaning cylindrical air filters
AU2007288104B2 (en) * 2006-08-21 2011-06-30 Stuart Cole Apparatus for cleaning cylindrical air filters
EP2320071A3 (en) * 2009-11-05 2014-02-12 General Electric Company Active flow control system for wind turbine

Also Published As

Publication number Publication date
ES2138326T3 (en) 2000-01-01
DE69604573T2 (en) 2000-01-20
US5958093A (en) 1999-09-28
AU4953096A (en) 1996-10-08
ITMI950546A0 (en) 1995-03-20
MX9707164A (en) 1998-07-31
ITMI950546A1 (en) 1996-09-20
EP0814892A1 (en) 1998-01-07
BR9607684A (en) 1999-11-30
EP0814892B1 (en) 1999-10-06
JPH11502762A (en) 1999-03-09
DE69604573D1 (en) 1999-11-11
DK0814892T3 (en) 2000-03-20
GR3031556T3 (en) 2000-01-31
IT1277170B1 (en) 1997-11-05
ATE185283T1 (en) 1999-10-15

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