WO2000057380A1 - Magnetically actuated float switch - Google Patents
Magnetically actuated float switch Download PDFInfo
- Publication number
- WO2000057380A1 WO2000057380A1 PCT/US1999/030440 US9930440W WO0057380A1 WO 2000057380 A1 WO2000057380 A1 WO 2000057380A1 US 9930440 W US9930440 W US 9930440W WO 0057380 A1 WO0057380 A1 WO 0057380A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- float
- float rod
- control apparatus
- magnetic
- switch
- Prior art date
Links
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
- G01F23/00—Indicating or measuring liquid level or level of fluent solid material, e.g. indicating in terms of volume or indicating by means of an alarm
- G01F23/30—Indicating or measuring liquid level or level of fluent solid material, e.g. indicating in terms of volume or indicating by means of an alarm by floats
- G01F23/64—Indicating or measuring liquid level or level of fluent solid material, e.g. indicating in terms of volume or indicating by means of an alarm by floats of the free float type without mechanical transmission elements
- G01F23/72—Indicating or measuring liquid level or level of fluent solid material, e.g. indicating in terms of volume or indicating by means of an alarm by floats of the free float type without mechanical transmission elements using magnetically actuated indicating means
- G01F23/74—Indicating or measuring liquid level or level of fluent solid material, e.g. indicating in terms of volume or indicating by means of an alarm by floats of the free float type without mechanical transmission elements using magnetically actuated indicating means for sensing changes in level only at discrete points
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
- H01H36/00—Switches actuated by change of magnetic field or of electric field, e.g. by change of relative position of magnet and switch, by shielding
- H01H36/02—Switches actuated by change of magnetic field or of electric field, e.g. by change of relative position of magnet and switch, by shielding actuated by movement of a float carrying a magnet
Definitions
- the present invention relates to a magnetically actuated float switch which is actuated in response to a changing fluid level, particularly a magnetically actuated float switch which utilizes a float rod magnet that may be interposed between two repellingly arranged magnetic bodies and the resulting magnetic interaction results in the actuation of a switch.
- the present magnetically actuated float switch is capable of being operably connected to a electric load device such as a pump.
- Liquid level sensing float switches have been in use for some time. These switches have been commonly used in conjunction with pumps or other electrical load devices, such as alarms, solenoid valves, semiconductor devices and the like.
- the switches When used in connection with pumps, the switches are typically used to detect a desired liquid level, and when the desired level is reached or exceeded the switch actuates and subsequently activates the pump, which functions to displace the liquid until the level falls below the desired level.
- the liquid level is typically detected by a float which is freely moveable about and along a support member or rod, with the float controlling the actuation of a switch element as it moves up and down vertically along the float rod in response to the liquid level.
- the switch When liquid level rises above a set point the switch will actuate in a first manner, and when the liquid level falls below a set point the switch will actuate in a second manner.
- US 4943210 to Bailey, Jr. et al entitled "Pump Control System, Level Sensor Switch and Switch Housing” utilizes a fluid pump, a partially hollow cylindrical float buoy which is disposed about a stem, and a reed switch.
- the stem is conductively connected to a pump.
- Within the stem at a predetermined level is a normally open reed switch.
- Within the float buoy is a ring shaped magnet that surrounds the stem.
- the magnetic nature of the ring magnet causes the reeds in the switch to be repelled away from the magnet thus forcing the reeds together.
- the mutual contact of the reeds closes the switch and activates a timer.
- This type of arrangement does not provide a uniform switching action and is not well suited to high vibration pump applications.
- Another example of a float switch using magnets is US 5030803 to
- Yarbrough entitled “Offset Float Switch”.
- Yarbrough provides for a switch that may be actuated by two floats, within the floats are switching magnets which allow the switch to be actuated when fluid level drops to a first level and actuated to a second position when the liquid rises to a second level which is above the first level.
- Yarbrough utilizes a central stem with the floats disposed thereabout, and a reed switch within the stem. This type of arrangement does not provide a uniform switching action and is not well suited to high vibration pump applications.
- the present invention provides for a magnetically actuated float switch for turning on and off an electrical load device which utilizes both an attracting force and a repelling force, which cumulatively provide the force necessary to actuate the switch.
- Purely repelling magnetic arrangements are more prone to fail to activate.
- Purely attracting magnetic arrangements are more prone to fail to deactivate.
- a switch which is more uniform and consistent, so that the system can be tuned or configured to more reliably activate and deactivate as compared to the prior art. This is done with a bracket having magnetic ends which are arranged in a repelling arrangement.
- a float rod magnet is carried by a float rod which is arranged so that it moves vertically upwardly and downwardly, such that when the liquid rises over a predetermined level, the float rod magnet will magnetically interact with the two magnetic ends of the bracket, the float rod magnet being repelled by one end and attracted by the other, so that a more uniform and consistent force is created which causes the switching action.
- the float rod magnet As the float rod magnet is rising, it will initially be repelled downward by the closest magnetic end of the bracket. This creates a translational resistance which provides an equivalent downward force on the float, thereby storing potential energy in the float.
- the float rod magnet When the liquid level is high enough to overcome this downward force, the float rod magnet will be catapulted upwardly in between the two magnetic ends of the bracket, which transfers the potential energy stored in the float into kinetic energy creating a horizontal snap action switching action of the bracket which provides more switching force at the beginning of the switching movement.
- the repelling force decreases and the attracting force increases providing a more uniform cumulative force throughout the travel.
- the greater force at the end of the switching action is desirable since the electrical load device will remain on until the liquid level falls below a certain level.
- the greater switching force provided by using both repelling and attracting forces allows for smaller magnets to be utilized, and also makes the float switch well suited for high vibration applications, such as application in which a pump creates a lot of vibration which can cause premature failure.
- the inventive float switch provides for a control apparatus which is made up of a mounting member, a moveable bracket member attached to the mounting member which is moveable between a first bracket position (FBP) and a second bracket position (SBP) by application of an external force, and a switch.
- the bracket member has two ends, each of which has magnetic characteristics. The bracket ends are oriented in a repelling arrangement.
- the bracket is operatively connected to a switch, such that when the bracket is in the FBP the switch will typically be in it off state and when the bracket is in its SBP the switch will be in its on state.
- the control apparatus through the switch is connected to an electrical load device such as a pump.
- the switch utilized in the control apparatus is of a common design and is typically a microswitch, also known in the art as a precision snap-action switch.
- the microswitch may be configured (wired) so that the normal state of the switch is the off state so that when the bracket is moved to the SBP the switch is turned to its on state.
- This configuration is generally the default setup for most float switches and is useful for pump-down applications as are well known in the art.
- the microswitch may also be wired to provide for the ability to have the normal or first state to be the on state and the second state to be the off state. Such a configuration is useful for pump-up applications, which are equally known of in the art.
- the microswitch will normally have an actuating member which is biased by a biasing member.
- the biasing member acts to force the actuating member against the bracket to hold the bracket in its first position.
- the force applied to move the bracket to its second position must be sufficient to overcome the biasing force to depress the actuating member into its second position in order to turn the switch to its closed or on state.
- the biasing force will cause the actuating member and bracket to return to their first states, thus turning the switch back to its off or open state.
- the force required for moving the bracket from the first position to the second position is supplied by a float rod magnet which is positioned so that it magnetically interacts with the opposingly oriented magnetic bracket ends.
- a repelling force and an attracting force which combine to provide a force in a single direction which is sufficient to overcome the biasing force provided by the biasing member and to move the bracket from its first position to its second position. This force is sufficient to hold the bracket in the second position, thus keeping the switch and electrical load device in their on positions until the float rod magnet is removed.
- the float rod magnet is brought into the necessary proximity of the bracket members as a result of its position atop a vertically mounted float rod.
- the float rod will move into the control apparatus through a float tower as a result of a float forcibly engaging an upper float stop located along the length of the float rod.
- the float will engage the upper float stop when the fluid exceeds a first predetermined level.
- the float will no longer engage the upper float stop but, due to the increased amount of force provided by the combined magnetic interactions described above the bracket will remain in its second position. Only after the liquid drops below a second predetermined level and the float rests upon a lower float stop will the float rod magnet be forced to drop away from the bracket ends. This is due to the weight of the float against the lower float stop overcoming the magnetic forces at play.
- FIG. 1 is a side perspective view of the inventive magnetically actuated float pump in a pump-down sump pump application
- FIG. 2 is a top view of the inventive float switch showing the bracket in its first or open position
- FIG. 3 is a top view of the inventive float switch showing the bracket in its second or closed position
- FIG. 4 is perspective view of the inventive float switch
- FIG. 5 is a perspective view of the switch internal mechanism
- FIG. 6 is a top view of the switch
- FIG. 7 is a side view of the switch;
- FIG. 8 is an electrical schematic of the switch;
- FIG. 9 is a top down view of the microswitch showing the alternative normally open contact arrangement and a normally closed contact arrangement;
- FIG. 10 is a partially exploded side view showing the float rod and float rod pin removed from the float rod tower;
- FIG. 11 is a chart which represents the comparative strengths of the magnetically actuated float switch including the singular and cumulative effects of a repelling magnet force and an attracting magnet force on a third magnetic body
- FIG. 12 is the same view as shown in FIG. 10 showing the float rod supported by the float rod pin within the float rod tower.
- FIG. 1 shows the inventive magnetically actuated float switch, shown generally at 10, which is secured to a discharge pipe 12 for maintaining the level of a liquid in a sump 14 below a predetermined level 16.
- Float switch 10 includes a float rod 18 and a float 20. As the liquid level in sump 14 rises, the float 20 moves vertically along float rod 18 from liquid level 21 to liquid level 16, until it engages the float rod magnet carrier 22, causing it to rise vertically until the float switch is actuated turning the pump 24 on to lower the liquid level.
- the internal switching mechanism is sealed inside enclosure 23, which is ultrasonically welded to base 25.
- the inven-tive float switch could be used to switch on and off any electrical load device, such as an alarm, to actuate a solenoid valve or any other desired application.
- the float 20 may be any standard float, such as a solid member formed of light weight material having a density less than the fluid to be pumped, or an open bottom float, which are both well known in the art.
- the inventive magnetically actuated float switch can be used in connection with any liquid, but is described below in connection with water or sewage.
- FIGS. 2, 3 and 4 show the various exposed components of the inventive magnetically actuated float switch 10.
- the moveable bracket member 26 is shown pivotally mounted to the mounting member 28 at a pivot pin 30.
- the moveable bracket member 26 may either snap fit to pivot pin 30 or may be arranged to lower it onto pivot pin 30.
- mounting member 28, moveable bracket member 26 and pivot pin 30 are made of molded plastic, although they may be made of any desired material.
- the moveable bracket member 26 has a first magnetic end 32, a second magnetic end 34 and a lever arm 36 which rests against an actuating member 38.
- the actuating member 38 is operatively connected to the precision microswitch 40.
- the microswitch 40 may be toggled between its two states by depressing the actuating member 38 from its normally open first position to its depressed second position.
- microswitch 40 is electrically configured so that it has a normally open contact arrangement (discussed further below in connection with FIG. 9).
- FIGS. 5-8 the microswitch 40 is shown in more detail where it can be seen that biasing element 42 maintains actuating member 38 in a normally open position.
- actuating member 38 When actuating member 38 is depressed, its base section 43 applies tension to switch elements 45, 47 and 49. The tension applied to center element 47 is enough to overcome the force of curved elements 53 and 55, which causes the switch contact 57 to move against contact 52.
- biasing element or spring 42 pushes against actuating member 38 causing switch contact 57 to move against contact 54.
- FIG. 8 shows the electrical schematic showing contact 50 switching between contact 52 and 54.
- the microswitch when common contact 50 is electrically connected to contact 52, as indicated by line 100, the microswitch operates with a normally open contact arrangement so that the electrical load device is off unless the microswitch 40 is put into its second state by depressing actuating member 38.
- a normally open contact arrangement is widely used in applications such as pump-down sump pumps.
- the microswitch 40 may also alternatively have contact 50 electrically connected to contact 54, as indicated by line 102, which configures the microswitch to a normally closed contact arrangement, so that the electrical load device is on unless the microswitch 40 is put into its second state by depressing actuating member 38.
- a normally closed contact arrangement is widely used in applications such as pump-up applications.
- the actuating member 38 is normally maintained in the fully extended first position through the application of a biasing force supplied by a biasing element 42.
- a biasing force supplied by a biasing element 42 supplied by the biasing element 42 against the actuating member 38 and transferred to the lever arm 36 is sufficient to push the moveable bracket member 26 counter-clockwise around the pivot point 30.
- the extent of this motion is limited by the presence of the first outside wall 44 of the float rod tower 46 against the first magnetic end 32 of the moveable bracket member 26.
- the moveable bracket member is defined as being in its first or open position.
- the float switch is shown in its second state in FIG. 3, in which bracket 26 has been rotated by an external force, discussed in more detail further below, to its second or closed position, in which second outside wall 48 of the float rod tower 46 abuts inside surface 51 of the magnetic end 34.
- the float rod which carries the float rod magnet 64 will be discussed in greater detail below.
- the float rod magnet 64 as shown in FIG. 2 is far enough below the magnetic ends 32 and 34 so that it does not magnetically interact with them.
- the liquid level has raised the float rod magnet 64 enough to magnetically interact with magnetic ends 32 and 34, causing the bracket 26 to rotate to its closed position.
- lever arm 36 supplies enough force on actuating member 38 to overcome the biasing force of biasing element 42.
- float rod 18 is shown before assembly with float rod tower 46.
- Attached to the top of float rod 18 is float rod magnet carrier 22 which carries float rod magnet 64.
- magnetic end 32 is in an repelling arrangement with magnet 64
- magnetic end 34 is in an attracting arrangement with magnet 64. This also results in magnetic ends 32 and 34 being arranged in a repelling fashion.
- This arrangement which utilizes both an attracting force and a repelling force, acting in the same direction, has been found to have several advantages over the prior art.
- the graph shown in FIG. 11 shows the sum 90 of both the attracting 92 and repelling 94 forces between magnetic ends 32, 34 and float rod magnet 64.
- the greater switching force provided by using both repelling and attracting forces allows smaller magnets to be utilized, and also makes the float switch well suited for high vibration applications, such as application in which a pump creates a lot of vibration which can prematurely deactuate the switch. Also, by combining the attracting and repelling forces a greater force is achieved than by using a single magnetic end on the bracket 26. Furthermore, acceleration as magnetic end 34 and float rod magnet 64 move so that inside surface 51 abuts outside surface 48 of the float rod tower 46 gives the bracket 26 a "snap- action" which has been found to be desirable. Referring again to FIG.
- this magnetic arrangement also conveniently keeps the switch in its closed or on state until the float rod magnet 64 has been lowered by a lower liquid level enough so that the float 20, places enough weight on the lower float rod stop 68 to overcome the attracting force between magnetic end 34 and float rod magnet 64. Once the liquid level is low enough to place enough weight on stop 68, the float rod 18 will lower vertically so that float rod magnet 64 no longer magnetically interacts with magnetic ends 32 or 34.
- Float 20 is arranged around float rod 18 and moves upwardly and downwardly on float rod 18 between an upper float stop 74 and a lower float rod stop 68.
- the float rod magnet carrier 22 has an upper portion sized to fit within float rod tower 46, and a narrower lower portion 70 which extends out of the open bottom of float rod tower 46, as best seen in FIG. 12.
- a removable pin 72 forms a barrier which prevents the wider upper portion of 62, or shoulder 63, from lowering below pin 72.
- the float rod magnet carrier 22 is confined to a range of motion between pin 72 and the closed top of float rod tower 46. The range of motion may altered by changing the height of the float rod tower 46.
- the bottom of lower portion 70 forms an upper float stop 74, which is engaged by the float 20 to raise float rod magnet carrier 22 as the liquid level rises.
- the carrier 22 is inserted into float rod tower 46 and pin 72 is inserted into hole 76. This is shown in FIG. 10 and FIG. 12.
- the upper float stop 74 is seen as a molded extension of the lower portion 70 of carrier 22.
- lower float stop 68 is shown as a cylindrical body or grommet which frictionally fits around float rod 18, and if desirable may be adjustable by sliding to a new position.
- the float stops 68 5 and 74 may be embodied in different forms wherein the stops 68 and 74 may either be fixed or alternatively moveable along the float rod 18 so that the range of motion of the float 20 between the two float stops 68 and 74 may be varied.
- Moveable stops are well known within the art and may include but are not limited to devices such as clips, tabs, grommets, etc.
- the carrier 22 will continue to rise with the float 20 and fluid level 16 until the carrier 22 abuts the closed top portion of the float rod tower 46.
- the float rod magnet 64 is carried by the float rod magnet carrier 22. As a result of the float rod 18 rising to the top of the float rod tower 46, the float rod magnet 64 will magnetically interact with the repellingly arranged magnetic ends 32 and
- the combined repelling and attracting magnetic fields create a combination force sufficient to overcome the biasing force supplied by biasing element 42 against the actuating member 38.
- the bracket member 26 is moved from the normally first or open position shown in FIG. 2 to the second or closed position shown in FIG. 3, thus depressing the actuating member 38 and placing the microswitch 40 into the open or on state, which turns on the pump 24.
- bracket ends 32 and 34 The magnetic interactions between the bracket ends 32 and 34, and the float rod magnet 64 are sufficient to keep the float rod 18 in its raised position despite the initial lowering and disengaging of the float 20 from the upper float stop 74, as the liquid level lowers. Therefore, the pump will remain on until the float rod magnet 64 is magnetically disengaged from bracket ends 32 and 34, as discussed further below.
- the float 20 will eventually encounter the lower float stop 68. With a continued drop in the liquid level the weight of the float 20 pressing on the lower float stop 68 will be sufficient to overcome the magnetic interactions described above and force the carrier 22 to descend inside the float rod tower 46 until the shoulder 63 abuts or rests on pin 72 within the float rod tower 46.
- the force exerted by the biasing member 42 is sufficient to force the actuating member 38 back to its first fully extended or closed position.
- the force supplied by the biasing element 42 to the actuating member 38 is in turn transferred to the lever arm 36.
- the lever arm 36 is pushed away from the microswitch 40 resulting in the bracket moving from the second position back to the original first position with a rapid snap-action.
- the microswitch 40 will be turned back to the normally first or 'off ' state, as will the pump or other electrical load device 24 which is operably connected to the magnetically actuated float switch.
- the described operation could be utilized in a pump-up application simply by electrically connecting 50 and 54 instead of contacts 50 and 52, such that the pump 24 is normally on and is turned off when the microswitch is actuated by float 20.
- the above magnetically actuated float switch has many uses and embodiments, the preferred use is to act as an operating means for a pump or other fluid controlling device.
- Some examples of other uses for the present magnetically actuated float switch include using the float switch to trigger a warning alarm or signaling means, or as a means for operating a regulatory valve, or seal.
- the components of the present magnetically actuated float switch may also vary depending on the use. For instance when used in water the float may be configured with different weight and buoyancy characteristics as opposed to when used in oil or other heavy fluids.
Abstract
Description
Claims
Priority Applications (4)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
AU20577/00A AU2057700A (en) | 1999-03-19 | 1999-12-17 | Magnetically actuated float switch |
EP99964306A EP1203360B1 (en) | 1999-03-19 | 1999-12-17 | Magnetically actuated float switch |
DE69931196T DE69931196T2 (en) | 1999-03-19 | 1999-12-17 | MAGNETICALLY ACTIVATED SWIM SWITCH |
CA2367577A CA2367577C (en) | 1999-03-19 | 1999-12-17 | Magnetically actuated float switch |
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US09/272,438 US6140925A (en) | 1999-03-19 | 1999-03-19 | Magnetically actuated float switch |
US09/272,438 | 1999-03-19 |
Publications (1)
Publication Number | Publication Date |
---|---|
WO2000057380A1 true WO2000057380A1 (en) | 2000-09-28 |
Family
ID=23039794
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
PCT/US1999/030440 WO2000057380A1 (en) | 1999-03-19 | 1999-12-17 | Magnetically actuated float switch |
Country Status (6)
Country | Link |
---|---|
US (1) | US6140925A (en) |
EP (1) | EP1203360B1 (en) |
AU (1) | AU2057700A (en) |
CA (2) | CA2367577C (en) |
DE (1) | DE69931196T2 (en) |
WO (1) | WO2000057380A1 (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2017146929A1 (en) * | 2016-02-26 | 2017-08-31 | S.J. Electro Systems, Inc. | Magnetically actuated switch |
Families Citing this family (21)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6337632B1 (en) | 2001-03-20 | 2002-01-08 | Orsi Homes Limited | Sump pump and moisture alarm |
US20050271517A1 (en) * | 2004-06-07 | 2005-12-08 | Terrell Eric J | Emergency automatic sump valve |
US7710283B1 (en) * | 2008-01-31 | 2010-05-04 | Christopher Ralph Cantolino | Fluid-level sensing device with encapsulated micro switch |
US8149122B2 (en) * | 2008-03-05 | 2012-04-03 | Metropolitan Industries, Inc. | Liquid level detection system with floating RFID tag |
US8235111B2 (en) * | 2008-08-15 | 2012-08-07 | Cnx Gas Company Llc | Down-hole liquid level control for hydrocarbon wells |
US20100129232A1 (en) * | 2008-11-24 | 2010-05-27 | Keener Robert M | Float device for a sewage pump |
US20110052414A1 (en) * | 2009-09-02 | 2011-03-03 | Keener Robert M | Apparatus for Controlling a Pump |
US8430641B2 (en) * | 2010-02-18 | 2013-04-30 | Raymond Ascord Noel | Multiple switch float switch apparatus |
WO2016014055A1 (en) * | 2014-07-23 | 2016-01-28 | GALLAGHER, Timothy Andrew | Fuel storage water detector with trigger density |
US10193546B1 (en) * | 2015-01-23 | 2019-01-29 | S.J. Electro Systems, Inc. | Pump switching device |
US10550845B2 (en) | 2015-07-22 | 2020-02-04 | S. J. Electro Systems, Inc. | Liquid level sensing system |
US10711788B2 (en) | 2015-12-17 | 2020-07-14 | Wayne/Scott Fetzer Company | Integrated sump pump controller with status notifications |
CN108261065A (en) * | 2016-12-31 | 2018-07-10 | 浙江绍兴苏泊尔生活电器有限公司 | food preparation appliance |
USD893552S1 (en) | 2017-06-21 | 2020-08-18 | Wayne/Scott Fetzer Company | Pump components |
USD890211S1 (en) | 2018-01-11 | 2020-07-14 | Wayne/Scott Fetzer Company | Pump components |
US20190234397A1 (en) * | 2018-02-01 | 2019-08-01 | Gp Enterprises Co., Ltd | Vertical-Shaft Sewage Pump with Anti-Collision Switch |
US10794379B2 (en) | 2018-02-05 | 2020-10-06 | Alderon Industries, Inc. | Sump pump control |
CN108899248A (en) * | 2018-08-30 | 2018-11-27 | 江苏环力科技发展股份有限公司 | A kind of float switch for water pump water supply system |
CN110119164A (en) * | 2019-05-15 | 2019-08-13 | 北京科瑞乐航空油料设备有限公司 | A kind of self-check type magnetic controlled liquid level valve |
US11830691B1 (en) * | 2019-06-03 | 2023-11-28 | Diversitech Corporation | Latching magnetic float switch |
US11749478B1 (en) * | 2019-06-03 | 2023-09-05 | Diversitech Corporation | Magnetic latching float switch |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3242474A (en) * | 1963-01-31 | 1966-03-22 | Holley Carburetor Co | Fluid dispenser and level indicator |
US3750124A (en) * | 1971-09-20 | 1973-07-31 | Bendix Corp | Fluid level switch |
US5621393A (en) * | 1994-08-22 | 1997-04-15 | Unimess Messtechnische Ger ate GmbH | Fill-level test and measuring device |
Family Cites Families (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE2062451A1 (en) * | 1970-12-18 | 1972-06-29 | Rieger W | Magnetic float switch |
US5155311A (en) * | 1991-07-03 | 1992-10-13 | S.J. Electro Systems, Inc. | Float switch assembly for submersible pump |
-
1999
- 1999-03-19 US US09/272,438 patent/US6140925A/en not_active Expired - Lifetime
- 1999-12-17 DE DE69931196T patent/DE69931196T2/en not_active Expired - Lifetime
- 1999-12-17 EP EP99964306A patent/EP1203360B1/en not_active Expired - Lifetime
- 1999-12-17 AU AU20577/00A patent/AU2057700A/en not_active Abandoned
- 1999-12-17 CA CA2367577A patent/CA2367577C/en not_active Expired - Lifetime
- 1999-12-17 CA CA2694446A patent/CA2694446C/en not_active Expired - Lifetime
- 1999-12-17 WO PCT/US1999/030440 patent/WO2000057380A1/en active IP Right Grant
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3242474A (en) * | 1963-01-31 | 1966-03-22 | Holley Carburetor Co | Fluid dispenser and level indicator |
US3750124A (en) * | 1971-09-20 | 1973-07-31 | Bendix Corp | Fluid level switch |
US5621393A (en) * | 1994-08-22 | 1997-04-15 | Unimess Messtechnische Ger ate GmbH | Fill-level test and measuring device |
Non-Patent Citations (1)
Title |
---|
See also references of EP1203360A4 * |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2017146929A1 (en) * | 2016-02-26 | 2017-08-31 | S.J. Electro Systems, Inc. | Magnetically actuated switch |
US10141141B2 (en) | 2016-02-26 | 2018-11-27 | S. J. Electro Systems, Inc. | Magnetically actuated switch |
Also Published As
Publication number | Publication date |
---|---|
CA2694446A1 (en) | 2000-09-28 |
EP1203360B1 (en) | 2006-05-03 |
AU2057700A (en) | 2000-10-09 |
EP1203360A1 (en) | 2002-05-08 |
DE69931196T2 (en) | 2007-03-08 |
US6140925A (en) | 2000-10-31 |
DE69931196D1 (en) | 2006-06-08 |
EP1203360A4 (en) | 2003-01-08 |
CA2367577A1 (en) | 2000-09-28 |
CA2694446C (en) | 2011-11-29 |
CA2367577C (en) | 2010-05-18 |
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