Dry bulk level sensing system

Claim 2

For use in a dry bulk storage vessel in which the level of dry bulk material contained therein is to be determined, a levelsensing system comprising: an elongated level sensor operative to provide a resistance the magnitude of which varies in direct relation to the level of material surrounding the sensor, said sensor being adapted for free-hanging disposition within said material; means for mounting said level sensor within said material in a position offset from the inlet axis of said storage vessel and displaced from the sidewall of said vessel, said means including a mounting assembly adapted to be secured to said vessel and attached to the upper end of said sensor and operative to support said sensor in said material; means for equalizing pressure variations between the interior of said sensor and the environment while preventing moisture from entering the sensor interior; and a weight rigidly secured to the lower end of said sensor and operative to assist in the free-hanging alignment thereof.

Claim 3

For use in a dry bulk storage vessel in which the level of dry bulk material contained therein is to be determined, a level-sensing system comprising: an elongated level sensor operative to provide a resistance the magnitude of which varies in direct relation to the level of material surrounding the sensor, said sensor being adapted for free hanging disposition within said material; means for mounting said level sensor within said material in a position offset from the inlet axis of said storage vessel and displaced from the sidewall of said vessel, said means including a mounting assembly adapted to be secured to said vessel and attached to the upper end of said sensor and operative to support said sensor in said material; means for equalizing pressure variations between the interior of said sensor and the environment while preventing moisture from entering the sensor interior; and wherein said mounting assembly includes: a housing having a bearing surface formed therein; a collar pivotally mounted on said bearing surface and rigidly connected to the upper end of said level sensor; means for sealingly mounting said assembly to a mounting surface of said vessel; means for coupling the electrical output of said sensor to utilization circuitry; means communicating between the sensor interior and the interior of said housing; and spring means disposed in said housing and operative to lessen transient forces encountered during system operation.

Claim 4

For use in a dry bulk storage vessel in which the level of dry bulk material contained therein is to be determined, a level-sensing system comprising: an elongated level sensor operative to provide a resistance the magnitude of which varies in direct relation to the level of material surrounding the sensor, said sensor being adapted for free hanging disposition within said material; means for mounting said level sensor within said material in a position offset from the inlet axis of said storage vessel and displaced from the sidewall of said vessel, said means including a mounting assembly adapted to be secured to said vessel and attached to the upper end of said sensor and operative to support said sensor in said material; means for equalizing pressure variations between the interior of said sensor and the environment while preventing moisture from entering the sensor interior; and wherein said mounting assembly includes: a housing having a bearing surface formed therein; a collar pivotally mounted on said bearing surface and rigidly connected to the upper end of said level sensor; means for sealingly mounting said assembly to a mounting surface of said vessel; means for coupling the electrical output of said sensor to utilization circuitry; means communicating between the sensor interior and the interior of said housing; and spring means disposed in said housing and operative to lessen transient forces encountered during system operation.

Claim 5

A level-sensing system according to claim 2, wherein said level sensor includes: a high tensile strength electrically conductive base strip; an electrical insulative material partially surrounding said base strip to define an uninsulated opening along the length of one side of said base strip; a precision resistance wire helically wound around the insulated base strip, the portions of the wire bridging the uninsulated opening being adapted to contact respective exposed confronting portions of the base strip in the presence of surrounding pressure; and a flexible multilayer jacket of high tensile strength surrounding the insulated base strip and resistance wire, said jacket being sensitive to surrounding pressure while being substantially impermeable to moisture.

Claim 6

A level-sensing system according to claim 3 wherein said jacket includes a metallized layer and means for electrically connecting the metallized surface of said layer to electrical ground.

Claim 7

A level-sensing system according to claim 3 wherein said mounting assembly includes: a housing having an opening in the bottom face thereof and a bearing surface formed in said opening; a collar having an upper hemispherical portion cooperative with said bearing surface for providing pivotal movement thereon and a generally cylindrical portion surrounding the upper end of said sensor, said collar having an electrically insulated pin for securing said base strip to said collar; first and second wires connected respectively to said resistance wire and to said base strip; and an encapsulant securing said sensor within said collar.

Claim 8

A level sensing system according to claim 5 wherein said collar further includes a tube disposed therein and communicating between the interior of said sensor and the interior of said housing.

Claim 9

A level sensing system according to claim 5 wherein said collar further includes a first tube disposed therein and communicating between the interior of said sensor and the interior of said housing; and a second tube disposed within said collar and communicating between the interior of said housing and the interior of said storage vessel.

Claim 10

For use in a dry bulk storage vessel in which the level of dry bulk material contained therein is to be determined, a level-sensing system comprising: an elongated level sensor disposed along substantially the full height of said storage vessel and operative to provide a resistance the magnitude of which varies in direct relation to the level of material surrounding the sensor, said sensor being adapted for and having sufficient weight to permit free hanging disposition within said material; means for mounting said level sensor within said material in a position offset from the inlet axis of said storage vessel and displaced from the sidewall of said vessel, said means including a mounting assembly adapted to be secured to said vessel and attached to the upper end of said sensor and operative to support said sensor in said material, said mounting assembly including a housing having a bearing surface formed on one face thereof; a collar rigidly secured to the upper end of said level sensor and having an upper portion cooperative with said bearing surface to permit pivotal movement of said collar and sensor; means for sealingly mounting said housing to a mounting surface of said vessel; means for coupling the electrical output of said sensor to utilization circuitry; and means communicating between the sensor interior and the interior of said housing; and means for equalizing pressure variations between the interior of said sensor and the environment while preventing moisture from entering the sensor interior.

Claim 11

For use in a dry bulk storage vessel in which the level of dry bulk material contained therein is to be determined, a level-sensing system comprising: an elongated level sensor disposed along substantially the full height of said storage vessel and operative to provide a resistance the magnitude of which varies in direct relation to the level of material surrounding the sensor, said sensor being adapted for and having sufficient weight to permit free hanging disposition within said material; means for mounting said level sensor within said material in a position offset from the inlet axis of said storage vessel and displaced from the sidewall of said vessel, said means including a mounting assembly adapted to be secured to said vessel and attached to the upper end of said sensor and operative to support said sensor in said material, said mounting assembly including a housing having a bearing surface formed on one face thereof; a collar rigidly secured to the upper end of said level sensor and having an upper portion cooperative with said bearing surface to permit pivotal movement of said collar and sensor; means for sealingly mounting said housing to a mounting surface of said vessel; means for coupling the electrical output of said sensor to utilization circuitry; and means communicating between the sensor interior and the interior of said housing; and means for equalizing pressure variations between the interior of said sensor and the environment while preventing moisture from entering the sensor interior.

Claim 12

A level sensing system according to claim 8 wherein said means for equalizing pressure variations includes a breather coupling the interior of said sensor and the interior of said housing.

Claim 13

A level sensing system according to claim 9 wherein said breather includes: an enclosure having a moisture-absorbing material disposed therein; a capillary breather tube disposed within said enclosure and having one end terminating within said enclosure and an opposite end terminating exteriorly of said enclosure; and a tube coupling the interior of said enclosure with the interior of said sensor.

Claim 14

A level-sensing system according to claim 10 wherein said capillary breather tube has an internal volume approximately equal to the internal volume of said sensor.

Claim 15

A level sensing system according to claim 8 wherein said means for equalizing pressure variations includes a sealed bag containing moisture absorbing material and coupled to the interior of said sensor, said bag being of sufficient volume to accommodate differential pressures experienced by said sensor.

Claim 16

For use in a dry bulk storage vessel in which the level of dry bulk material contained therein is to be determined, a level-sensing system comprising: an elongated level sensor operative to provide a resistance the magnitude of which varies in direct relation to the level of material surrounding the sensor, said sensor being adapted for free-hanging disposition with said material; means for mounting said level sensor within said material in a position offset from the inlet axis of said storage vessel and displaced from the sidewall of said vessel, said means including a mounting assembly adapted to be secured to said vessel and attached to the upper end of said sensor and operative to support said sensor in said material; means for equalizing pressure variations between the interior of said sensor and the environment while preventing moisture from entering the sensor interior; and wherein said mounting assembly includes: a sealed housing having a bearing surface on one face thereof; a collar rigidly secured to the upper end of said level sensor and having an upper portion cooperative with said bearing surface to permit pivotal movement of said collar and sensor; a sealed connector mounting in a wall of said housing for coupling the electrical output of said sensor to utilization means.

Claim 17

For use in a dry bulk storage vessel in which the level of dry bulk material contained therein is to be determined, a level-sensing system comprising: an elongated level sensor operative to provide a resistance the magnitude of which varies in direct relation to the level of material surrounding the sensor, said sensor being adapted for free-hanging disposition with said material; means for mounting said level sensor within said material in a position offset from the inlet axis of said storage vessel and displaced from the sidewall of said vessel, said means including a mounting assembly adapted to be secured to said vessel and attached to the upper end of said sensor and operative to support said sensor in said material; means for equalizing pressure variations between the interior of said sensor and the environment while preventing moisture from entering the sensor interior; and wherein said mounting assembly includes: a sealed housing having a bearing surface on one face thereof; a collar rigidly secured to the upper end of said level sensor and having an upper portion cooperative with said bearing surface to permit pivotal movement of said collar and sensor; a sealed connector mounting in a wall of said housing for coupling the electrical output of said sensor to utilization means.