US2669707A - Filter signal - Google Patents

Filter signal Download PDF

Info

Publication number
US2669707A
US2669707A US159053A US15905350A US2669707A US 2669707 A US2669707 A US 2669707A US 159053 A US159053 A US 159053A US 15905350 A US15905350 A US 15905350A US 2669707 A US2669707 A US 2669707A
Authority
US
United States
Prior art keywords
signal
valve
magnet
filter
armature
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
US159053A
Inventor
Frederick S Ehrman
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.)
Bowser Inc
Original Assignee
Bowser Inc
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 Bowser Inc filed Critical Bowser Inc
Priority to US159053A priority Critical patent/US2669707A/en
Application granted granted Critical
Publication of US2669707A publication Critical patent/US2669707A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • GPHYSICS
    • G08SIGNALLING
    • G08BSIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
    • G08B5/00Visible signalling systems, e.g. personal calling systems, remote indication of seats occupied
    • G08B5/02Visible signalling systems, e.g. personal calling systems, remote indication of seats occupied using only mechanical transmission
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D35/00Filtering devices having features not specifically covered by groups B01D24/00 - B01D33/00, or for applications not specifically covered by groups B01D24/00 - B01D33/00; Auxiliary devices for filtration; Filter housing constructions
    • B01D35/14Safety devices specially adapted for filtration; Devices for indicating clogging
    • B01D35/143Filter condition indicators
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B01PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01DSEPARATION
    • B01D35/00Filtering devices having features not specifically covered by groups B01D24/00 - B01D33/00, or for applications not specifically covered by groups B01D24/00 - B01D33/00; Auxiliary devices for filtration; Filter housing constructions
    • B01D35/14Safety devices specially adapted for filtration; Devices for indicating clogging
    • B01D35/147Bypass or safety valves
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16NLUBRICATING
    • F16N29/00Special means in lubricating arrangements or systems providing for the indication or detection of undesired conditions; Use of devices responsive to conditions in lubricating arrangements or systems
    • F16N29/04Special means in lubricating arrangements or systems providing for the indication or detection of undesired conditions; Use of devices responsive to conditions in lubricating arrangements or systems enabling a warning to be given; enabling moving parts to be stopped
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16NLUBRICATING
    • F16N39/00Arrangements for conditioning of lubricants in the lubricating system
    • F16N39/06Arrangements for conditioning of lubricants in the lubricating system by filtration
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10STECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S116/00Signals and indicators
    • Y10S116/42Oil filter

Definitions

  • This invention relates to a filter signal. More specifically, it relates to a signal which is displayed when the filter requires attention;
  • Another object of the invention is to provide a signal which is simple and inexpensive.
  • a further object is to provide a signal which may be reset when the cartridge has been changed.
  • the single figure is an elevation in section with parts broken away to show the by-pass valve.
  • the numeral i represents a filter case having an inlet 3 and an outlet 5.
  • the case is in two parts 6, l which have mating flanges 9, H held together by suitable fasteners [3.
  • the outlet in part I is provided with a suitable outlet tube i5 on which a head ii is slidably mounted and sealed by a ring it disposed in groove 20.
  • the part 5 is provided with a fitting l9 having a stem 2
  • This stem includes a projection 23 which enters and guides the upper head 25, and a shoulder 21 which bears on a gasket 29 to seal the upper head and stem.
  • a filter cartridge 30 of any suitable type is sealingly held between the heads, preferably by a spring 3
  • the projection 23 has a passage 33 which communicates at its upper end with an inlet passage in the stem and at its lower end with a by-pass chamber 31.
  • a magnet chamber 33 is formed in the stem above passage 33, preferably in axial alignment with 35 and 31, and has its lower end closed by a non-magnetic diaphragm M.
  • the stem is preferably also non-magnetic.
  • a valve 43 is mounted in valve chamber 31 and has a stem 45 which projects through passage 33 to a point closely adjacent the diaphragm where it terminates in an armature 41 disposed 4 Claims. (01. 240439) parallel to and closely adjacent the diaphragm.
  • a spring 49 disposed in the chamber 37, rests on a pin 5
  • 'A magnet 53 is slidably mounted in the chamber 39 and has a rod 55 which extends outwardly through the stem and supports at its upper end the signalbutton 57.
  • a spring 59 which bears on the stem and button normally urges the but-'- ton, rod and magnet upwardly.
  • This housing may be frictionally engaged with a boss 61 on the stem.
  • Liquid entering the inlet 3 normally passes through the filter cartridge and out the outlet tube l5 and outlet 5.
  • the filter becomes substantially impervious due to the accumulation of impurities removed from the liquid, the liquid will by-pass the cartridge by entering conduits 35, 33, will displace the valve 43 against the opposition of spring 49 and pass through chamber 37, tube 15 to outlet 5.
  • valve When the valve is thus displaced, it will draw the armature away from magnet 53 so as to reduce the force holding the magnet in place.
  • the spring 59 overcomes this force and moves the magnet, rod 55 and signal 51 upwardly so that the latter is visible in the windows 63.
  • the operator perceiving the signal knows that the cartridge should be replaced. He then shuts the required valves (not shown), removes the fasteners l3 and cover 6, removes head 25 and the filter cartridge. He will then replace the cartridge with a clean one, replace the parts mentioned above and the filter is again ready for operation. He will next remove the housing 6
  • valves may be opened and the filter restored to service.
  • a filter comprising a filtering medium, the combination of a signal having inefieotive and signalling positions, means for urging said signal toward signalling position, means normally holding said signal in ineffective position, a nor mally closed valve means, disposed so as to be opened by the increase in pressure resulting from substantial clogging of the medium, for by-passing liquid around said medium, an armature connected to be operated by said valve means, a magnet, a si nal m u ed fo movement between in v an s gna in pos tions, means urging i s gn l towa d si nall n p si ons, said armat e in di posed os ly adiaeent the magn t.
  • a normally closed valve means disposed so as to be opened by the increase in pressure resulting from substantial clogging of the medium, for by-pass- .ing liquid around said medium, an armature connected to be operated by said valve means, a magnet, a non-magnetic diaphragm disposed between the armature and magnet, a signal mounted for movement between inefiective and signalling positions, means urging said signal toward signalling position, said armature being disposed closely adjacent the magnet, when the valve is closed, so that the magnetic force will overcome the urging means and being connected to be moved away from said magnet when the valve is opened so that the urging means will overcome the magnetic force.

Landscapes

  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Mechanical Engineering (AREA)
  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Magnetically Actuated Valves (AREA)

Description

Feb. 16, 1954 s, EHRMAN 2,669,707
FILTER SIGNAL Filed April 29, 1950 Raf FREDERICK 5. E HRMHN INVEN TOR.
ATTORNEY Patented Feb. 16,1954 la:
Frederick S. Ehrman, Fort Wayne, Ind., assignor to Bowser, Inc., Fort Wayne, Ind., a corporation of Indiana Application April 29, 1950, Serial No. 159,053
This invention relates to a filter signal. More specifically, it relates to a signal which is displayed when the filter requires attention;
It is a well known fact that filters employing a filter cartridge, such as those used for cleaning plugged to the extent that liquid is being bypassed around the filter. V
Another object of the invention is to provide a signal which is simple and inexpensive.
A further object is to provide a signal which may be reset when the cartridge has been changed.
These and other objects will become apparent from a study of this specification and the drawing which is attachedhereto and made a part hereof, and in which:
The single figure is an elevation in section with parts broken away to show the by-pass valve.
The numeral i represents a filter case having an inlet 3 and an outlet 5. The case is in two parts 6, l which have mating flanges 9, H held together by suitable fasteners [3.
The outlet in part I is provided with a suitable outlet tube i5 on which a head ii is slidably mounted and sealed by a ring it disposed in groove 20.
The part 5 is provided with a fitting l9 having a stem 2| screwed into it. This stem includes a projection 23 which enters and guides the upper head 25, and a shoulder 21 which bears on a gasket 29 to seal the upper head and stem.
A filter cartridge 30 of any suitable type is sealingly held between the heads, preferably by a spring 3|.
The projection 23 has a passage 33 which communicates at its upper end with an inlet passage in the stem and at its lower end with a by-pass chamber 31.
A magnet chamber 33 is formed in the stem above passage 33, preferably in axial alignment with 35 and 31, and has its lower end closed by a non-magnetic diaphragm M. The stem is preferably also non-magnetic.
A valve 43 is mounted in valve chamber 31 and has a stem 45 which projects through passage 33 to a point closely adjacent the diaphragm where it terminates in an armature 41 disposed 4 Claims. (01. 240439) parallel to and closely adjacent the diaphragm. A spring 49, disposed in the chamber 37, rests on a pin 5| and urges the valve 43 closed.
'A magnet 53 is slidably mounted in the chamber 39 and has a rod 55 which extends outwardly through the stem and supports at its upper end the signalbutton 57. A spring 59 which bears on the stem and button normally urges the but-'- ton, rod and magnet upwardly.
A housing 6| having sight openings 53 which may be covered by a transparent insert tube 65, enable the position of the indicator button to be determined. This housing may be frictionally engaged with a boss 61 on the stem.
Operation Liquid entering the inlet 3 normally passes through the filter cartridge and out the outlet tube l5 and outlet 5. When the filter becomes substantially impervious due to the accumulation of impurities removed from the liquid, the liquid will by-pass the cartridge by entering conduits 35, 33, will displace the valve 43 against the opposition of spring 49 and pass through chamber 37, tube 15 to outlet 5.
When the valve is thus displaced, it will draw the armature away from magnet 53 so as to reduce the force holding the magnet in place. The spring 59 overcomes this force and moves the magnet, rod 55 and signal 51 upwardly so that the latter is visible in the windows 63.
The operator perceiving the signal, knows that the cartridge should be replaced. He then shuts the required valves (not shown), removes the fasteners l3 and cover 6, removes head 25 and the filter cartridge. He will then replace the cartridge with a clean one, replace the parts mentioned above and the filter is again ready for operation. He will next remove the housing 6|, push the indicator down until the magnetic force on the armature is great enough to overcome the spring 59 so that the indicator will be held down out of sight.
The valves may be opened and the filter restored to service.
It is obvious that various changes may be made in the form, structure and arrangement of parts without departing from the spirit of the invention. Accordingly, applicant does not desire to be limited to the specific embodiment disclosed herein primarily for purposes of illustration; but instead, he desires protection falling fairly within the scope of the appended claims.
What I claim to be new and desire to protect by Letters Patent of the United States is:
1. In a filter comprising a filtering medium, the
combination of a signal having inefiective and signalling positions, means for urging said signal toward signalling position, means normally holding said signal in ineffective position, a normally closed valve means, disposed so as to be opened by the increase in pressure resulting from substantial clogging of the medium, for by-passs l quid round sa d me m and means onerated bysaid valve means for releasing said holding means.
2. In a filter comprising a filtering medium, the combination of a signal having inefieotive and signalling positions, means for urging said signal toward signalling position, means normally holding said signal in ineffective position, a nor mally closed valve means, disposed so as to be opened by the increase in pressure resulting from substantial clogging of the medium, for by-passing liquid around said medium, an armature connected to be operated by said valve means, a magnet, a si nal m u ed fo movement between in v an s gna in pos tions, means urging i s gn l towa d si nall n p si ons, said armat e in di posed os ly adiaeent the magn t. when the valve is closed, so that t e m n t for will overcome the ur in means and be ng c nnected to be moved away from said mag wh n e valve is open d so that the r s m ns will vercome he ma n tic for e- '1 :3. In a liter comprisin a f te ing medium. th combinat n f a s nal avin in fiectlv and si nalli g p s tions, means for urging said sign l t wa d s nall n position, means normall holding said signal in ineffective position, a normally closed valve means, disposed so as to be opened by the increase in pressure resulting from substantial clogging of the medium, for by-pass- .ing liquid around said medium, an armature connected to be operated by said valve means, a magnet, a non-magnetic diaphragm disposed between the armature and magnet, a signal mounted for movement between inefiective and signalling positions, means urging said signal toward signalling position, said armature being disposed closely adjacent the magnet, when the valve is closed, so that the magnetic force will overcome the urging means and being connected to be moved away from said magnet when the valve is opened so that the urging means will overcome the magnetic force.
i, n a fi t r c pr si g a filterin m d um, the combination of a signal having inefieotive and signalling positions, means for urging said signal toward signalling position, means normally holding said signal in inefiective position, a normally closed valve means, disposed so as to be opened by the increase in pressure resulting from substantial clogging of the medium, for by-passing liquid around said medium, a signal mounted for movement between ineffective and signalling positions, a magnet and an armature mounted closely adjacent each other for movement with said valve and signal, means mounting said valve means for movement, and means operated by the valve to separat said armature and magnet, means ior urging said signal toward signalling position, said urging means exerting less force than s d ma ne and armature When the latter are close proximity and exerting greater force than the magnet and armature when the latter a e s par ted b a p det rmined amount, w r by s d s nal is moved to signallin position wh the a ve. m a s moved a distance sufficient to separate said armature and signal by said m unt.
S. EHRMAN.
References Cited in the file of this patent UIH'I'ED S ATES PATENTS
US159053A 1950-04-29 1950-04-29 Filter signal Expired - Lifetime US2669707A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US159053A US2669707A (en) 1950-04-29 1950-04-29 Filter signal

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US159053A US2669707A (en) 1950-04-29 1950-04-29 Filter signal

Publications (1)

Publication Number Publication Date
US2669707A true US2669707A (en) 1954-02-16

Family

ID=22570883

Family Applications (1)

Application Number Title Priority Date Filing Date
US159053A Expired - Lifetime US2669707A (en) 1950-04-29 1950-04-29 Filter signal

Country Status (1)

Country Link
US (1) US2669707A (en)

Cited By (38)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2757801A (en) * 1953-05-05 1956-08-07 Muggli Meinrad Signal devices for filters
US2878936A (en) * 1957-04-05 1959-03-24 Purolator Products Inc Filter unit
US2921157A (en) * 1955-05-26 1960-01-12 Bacharach Ind Instr Company Filter gauge
US2936731A (en) * 1958-07-21 1960-05-17 Nils O Rosaen Industrial oil filter control unit
US2942572A (en) * 1958-06-17 1960-06-28 Pall Corp Magnetic pressure indicator
US2954751A (en) * 1958-05-09 1960-10-04 Bendix Corp Visible filter clogging indicator
US3011470A (en) * 1960-03-18 1961-12-05 Thompson Ramo Wooldridge Inc Pressure change indicator
US3040894A (en) * 1960-07-12 1962-06-26 Pall Corp Filter
US3042076A (en) * 1959-01-27 1962-07-03 Purolator Products Inc Filter signal device
US3043262A (en) * 1959-03-24 1962-07-10 Purolator Products Inc Magnetic filter signal device
US3045826A (en) * 1958-07-28 1962-07-24 Permanent Filter Corp Filter device
US3070232A (en) * 1959-10-01 1962-12-25 Purolator Products Inc Filter unit with signal device
US3080972A (en) * 1958-07-28 1963-03-12 Permanent Filter Corp Filtering component
US3154049A (en) * 1962-02-19 1964-10-27 Screen Products Inc Magnetic pressure indicator
US3164164A (en) * 1960-02-02 1965-01-05 Pall Corp Pressure-responsive valves
US3204766A (en) * 1961-07-17 1965-09-07 Industrial Filter Pump Mfg Co Filter cake thickness detector
US3220375A (en) * 1963-03-28 1965-11-30 Eaton Mfg Co Lubrication indicator
US3250242A (en) * 1964-03-30 1966-05-10 William L Fisher Clogged filter indicator device
DE1233621B (en) * 1958-06-17 1967-02-02 Lloyd And Hillman Ltd Device for monitoring a pressure or a pressure difference
US3313264A (en) * 1964-09-02 1967-04-11 Ansul Chemical Co Pressure indicator
US3413951A (en) * 1964-06-15 1968-12-03 Holley Carburetor Co Differential pressure indicator
US3420266A (en) * 1963-09-20 1969-01-07 Aero Flow Dynamics Inc Combination magnetic bypass valve and indicator
US3448716A (en) * 1965-10-23 1969-06-10 Commercial Filters Corp Of Cal Magnetic pressure indicator
US3492968A (en) * 1968-07-08 1970-02-03 Gardner Denver Co Fluid actuated visual indicator
US3499415A (en) * 1967-02-17 1970-03-10 Btr Industries Ltd Indicator devices
US3720317A (en) * 1969-06-11 1973-03-13 Metaframe Corp Aquarium filter
US4053409A (en) * 1975-03-26 1977-10-11 Caterpillar Tractor Co. Removable filter assembly with bypass valve
US5237957A (en) * 1992-07-08 1993-08-24 Liucci Charles A Pressure indicator
US5461368A (en) * 1994-01-11 1995-10-24 Comtech Incorporated Air filter monitoring device in a system using multispeed blower
US5536394A (en) * 1994-11-17 1996-07-16 Recovery Engineering, Inc. End of life mechanism for water treatment cartridge
US5873995A (en) * 1997-05-06 1999-02-23 The Clorox Company End-of-life indicator for water treatment device
US5882507A (en) * 1996-04-30 1999-03-16 Recovery Engineering, Inc. Water filter cartridge end-of-life mechanism
EP1068888A1 (en) * 1999-07-13 2001-01-17 Hozelock Limited Filter assembly with bypass valve and indicator means
US6540909B2 (en) * 2001-03-07 2003-04-01 Davco Technology, Llc Fluid filter with pressure relief valve
US20040173511A1 (en) * 2002-03-22 2004-09-09 Mulder David Wayne Fluid filter with pressure relief valve
US6827846B2 (en) * 2001-07-25 2004-12-07 Parker-Hannifin Corporation Filter element change indicator handle
US20110062061A1 (en) * 2009-09-17 2011-03-17 Davco Technology, Llc Filter Assembly with Modular Relief Valve Interface
US20150298034A1 (en) * 2014-04-16 2015-10-22 Hydac Filtertechnik Gmbh Contamination indicator

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US392970A (en) * 1888-11-13 Fostee eitchie
US542664A (en) * 1895-07-16 Electric annunciator
US2328131A (en) * 1938-12-05 1943-08-31 Henry G Eisler Oil filter
US2348651A (en) * 1941-06-28 1944-05-09 Business Collaborators Inc Filter
US2497702A (en) * 1948-11-17 1950-02-14 Gen Electric Pressure responsive indicating device

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US392970A (en) * 1888-11-13 Fostee eitchie
US542664A (en) * 1895-07-16 Electric annunciator
US2328131A (en) * 1938-12-05 1943-08-31 Henry G Eisler Oil filter
US2348651A (en) * 1941-06-28 1944-05-09 Business Collaborators Inc Filter
US2497702A (en) * 1948-11-17 1950-02-14 Gen Electric Pressure responsive indicating device

Cited By (53)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2757801A (en) * 1953-05-05 1956-08-07 Muggli Meinrad Signal devices for filters
US2921157A (en) * 1955-05-26 1960-01-12 Bacharach Ind Instr Company Filter gauge
US2878936A (en) * 1957-04-05 1959-03-24 Purolator Products Inc Filter unit
US2954751A (en) * 1958-05-09 1960-10-04 Bendix Corp Visible filter clogging indicator
US3077854A (en) * 1958-06-17 1963-02-19 Pall Corp Magnetic pressure indicator
DE1233621B (en) * 1958-06-17 1967-02-02 Lloyd And Hillman Ltd Device for monitoring a pressure or a pressure difference
US2942572A (en) * 1958-06-17 1960-06-28 Pall Corp Magnetic pressure indicator
DE1276932B (en) * 1958-06-17 1968-09-05 Lloyd And Hillman Ltd Device for monitoring a pressure or a pressure difference
US2936731A (en) * 1958-07-21 1960-05-17 Nils O Rosaen Industrial oil filter control unit
US3045826A (en) * 1958-07-28 1962-07-24 Permanent Filter Corp Filter device
US3080972A (en) * 1958-07-28 1963-03-12 Permanent Filter Corp Filtering component
US3042076A (en) * 1959-01-27 1962-07-03 Purolator Products Inc Filter signal device
US3043262A (en) * 1959-03-24 1962-07-10 Purolator Products Inc Magnetic filter signal device
US3070232A (en) * 1959-10-01 1962-12-25 Purolator Products Inc Filter unit with signal device
US3164164A (en) * 1960-02-02 1965-01-05 Pall Corp Pressure-responsive valves
US3011470A (en) * 1960-03-18 1961-12-05 Thompson Ramo Wooldridge Inc Pressure change indicator
US3040894A (en) * 1960-07-12 1962-06-26 Pall Corp Filter
US3204766A (en) * 1961-07-17 1965-09-07 Industrial Filter Pump Mfg Co Filter cake thickness detector
US3154049A (en) * 1962-02-19 1964-10-27 Screen Products Inc Magnetic pressure indicator
US3220375A (en) * 1963-03-28 1965-11-30 Eaton Mfg Co Lubrication indicator
US3420266A (en) * 1963-09-20 1969-01-07 Aero Flow Dynamics Inc Combination magnetic bypass valve and indicator
US3250242A (en) * 1964-03-30 1966-05-10 William L Fisher Clogged filter indicator device
US3413951A (en) * 1964-06-15 1968-12-03 Holley Carburetor Co Differential pressure indicator
US3313264A (en) * 1964-09-02 1967-04-11 Ansul Chemical Co Pressure indicator
US3448716A (en) * 1965-10-23 1969-06-10 Commercial Filters Corp Of Cal Magnetic pressure indicator
US3499415A (en) * 1967-02-17 1970-03-10 Btr Industries Ltd Indicator devices
US3492968A (en) * 1968-07-08 1970-02-03 Gardner Denver Co Fluid actuated visual indicator
US3720317A (en) * 1969-06-11 1973-03-13 Metaframe Corp Aquarium filter
US4053409A (en) * 1975-03-26 1977-10-11 Caterpillar Tractor Co. Removable filter assembly with bypass valve
US5237957A (en) * 1992-07-08 1993-08-24 Liucci Charles A Pressure indicator
US5461368A (en) * 1994-01-11 1995-10-24 Comtech Incorporated Air filter monitoring device in a system using multispeed blower
US5536394A (en) * 1994-11-17 1996-07-16 Recovery Engineering, Inc. End of life mechanism for water treatment cartridge
US5785844A (en) * 1994-11-17 1998-07-28 Recovery Engineering, Inc. End of life mechanism for water treatment cartridge
US20040173507A1 (en) * 1996-04-30 2004-09-09 Pur Water Purification Products, Inc. Water treatment device with fill-counting cartridge
US5882507A (en) * 1996-04-30 1999-03-16 Recovery Engineering, Inc. Water filter cartridge end-of-life mechanism
US6881327B2 (en) 1996-04-30 2005-04-19 Pur Water Purification Products Water treatment device with fill-counting cartridge
US6423224B1 (en) 1996-04-30 2002-07-23 The Procter & Gamble Company Filter cartridge assembly for water treatment device
US5873995A (en) * 1997-05-06 1999-02-23 The Clorox Company End-of-life indicator for water treatment device
EP1068888A1 (en) * 1999-07-13 2001-01-17 Hozelock Limited Filter assembly with bypass valve and indicator means
US20110017658A1 (en) * 2000-07-25 2011-01-27 Davco Technology, Llc Filter Cartridge with Pressure Relief Valve
US9079129B2 (en) 2000-07-25 2015-07-14 Davco Technology, Llc Filter cartridge with divider
US20090065411A1 (en) * 2000-07-25 2009-03-12 Davco Technology, Llc Filter Cartridge with Pressure Relief Valve
US7854837B2 (en) 2000-07-25 2010-12-21 Davco Technology, Llc Filter cartridge with pressure relief valve
US6540909B2 (en) * 2001-03-07 2003-04-01 Davco Technology, Llc Fluid filter with pressure relief valve
US20030111396A1 (en) * 2001-03-07 2003-06-19 Smith Paul B. Fluid filter with pressure relief valve
US6841065B2 (en) * 2001-03-07 2005-01-11 Davco Manufacturing, L.L.C. Fluid filter with pressure relief valve
US6827846B2 (en) * 2001-07-25 2004-12-07 Parker-Hannifin Corporation Filter element change indicator handle
US20040173511A1 (en) * 2002-03-22 2004-09-09 Mulder David Wayne Fluid filter with pressure relief valve
US20110062061A1 (en) * 2009-09-17 2011-03-17 Davco Technology, Llc Filter Assembly with Modular Relief Valve Interface
US8574430B2 (en) 2009-09-17 2013-11-05 Davco Technology, Llc Filter assembly with modular relief valve interface
US9586163B2 (en) 2009-09-17 2017-03-07 Davco Technology, Llc Filter assembly with modular relief valve interface
US20150298034A1 (en) * 2014-04-16 2015-10-22 Hydac Filtertechnik Gmbh Contamination indicator
US10307700B2 (en) * 2014-04-16 2019-06-04 Hydac Filtertechnik Gmbh Contamination indicator

Similar Documents

Publication Publication Date Title
US2669707A (en) Filter signal
US3827558A (en) Fluid filter with bypass and condition indicator
US2935040A (en) Visible filter clogging indicator
GB1068574A (en) Magnetic pressure indicator
GB1429393A (en) Fluid filter
GB1047159A (en) Filter clogging indicator
US3128743A (en) Differential pressure responsive device
GB843165A (en) Combined full-flow and part-flow oil filter
GB1066341A (en) Oil filters
GB1015774A (en) Improvements in or relating to a filter device
GB1042372A (en) Improvements in fluid filters
GB1223803A (en) Differential pressure indicator
GB1316038A (en) Fluid filter devices
GB1321662A (en) Fluid filters
GB1075930A (en) Filter device
US3974795A (en) Differential pressure indicating device
US3103952A (en) Visible filter clogging indicator
GB1033206A (en) Improvements in or relating to filter devices
GB1080901A (en) Water-sensitive filter and flow monitor
US3412706A (en) Differential pressure indicator
US3448716A (en) Magnetic pressure indicator
US3420375A (en) Filter with automatic bypass-shutoff
GB1109241A (en) Filter
SU671056A1 (en) Liquid purification filter
GB1037837A (en) Improvements in or relating to strainers for liquids flowing under pressure