US3838518A — Material level indicator

Claim 1

Independent Claim 236 words

In a material level indicator of the drop-weight type, the combination comprising a housing having a central portion, a first cover associated with one side of said central portion and defining therewith upper and lower vertically aligned front chambers in which mechanical components are positioned, a second cover associated with the opposite side of said central portion to define a rear chamber in which electrical components are positioned, said central portion serving as a sealed barrier between said rear and front chambers, said mechanical components disposed in said upper chamber comprising a drum rotatably mounted on said central portion and having one end of a drop line attached thereto a counter pulley journalled on said central portion, and a level sensing lever pivoted on said central portion and rotatably supporting a level sensing pulley thereon, said drop line being trained over said pulleys and having a bob weight attached to it''s other end, said upper and lower front chambers having openings through which said drop line extends downwardly therefrom, a shut off switch operating lever pivoted to said central portion in said lower chamber and actuator means adapted to be engaged by said bob weight on said drop line to actuate said operating lever, said electric components comprising an electrical motor for driving said drum, a level sensing switch operatively connected with the level sensing lever and a shut-off switch operatively connected with said shut-off lever.

Claim 2

Dependent Claim 236 words

In a material level indicator of the drop-weight type, the combination comprising a housing having a central portion, a first cover associated with one side of said central portion and defining therewith upper and lower vertically aligned front chambers in which mechanical components are positioned, a second cover associated with the opposite side of said central portion to define a rear chamber in which electrical components are positioned, said central portion serving as a sealed barrier between said rear and front chambers, said mechanical components disposed in said upper chamber comprising a drum rotatably mounted on said central portion and having one end of a drop line attached thereto a counter pulley journalled on said central portion, and a level sensing lever pivoted on said central portion and rotatably supporting a level sensing pulley thereon, said drop line being trained over said pulleys and having a bob weight attached to it''s other end, said upper and lower front chambers having openings through which said drop line extends downwardly therefrom, a shut off switch operating lever pivoted to said central portion in said lower chamber and actuator means adapted to be engaged by said bob weight on said drop line to actuate said operating lever, said electric components comprising an electrical motor for driving said drum, a level sensing switch operatively connected with the level sensing lever and a shut-off switch operatively connected with said shut-off lever.

Claim 3

Dependent Claim 31 words

The combination set forth in claim 1 wherein said housing includes a wiping device positioned such that the drop line passes therethrough in traveling between said upper and lower front chambers.

Claim 4

Dependent Claim 31 words

The combination set forth in claim 2 including means operatively connecting said switchEs to the corresponding mechanical components comprises shafts extending through said central portion, and seals provided around said shafts.

Claim 5

Dependent Claim 41 words

The combination set forth in claim 3 wherein said seals comprise pressure responsive lip seals oriented to increase their sealing engagement with the associated shafts in response to an increase in pressure in said front chambers relative to said rear chamber.

Claim 6

Dependent Claim 67 words

The combination set forth in claim 4 wherein said actuator means comprises a tube with said drop line passing therethrough, and diaphragm means supporting said tube in the lower end of said housing such that the upper end of said tube projects into said lower chamber, said tube being lifted upon engagement by the bob weight during upward movement thereof to actuate said shut-off switch sensing lever.

Claim 7

Dependent Claim 68 words

The combination set forth in claim 5 wherein said diaphragm means comprises a tubular longitudinally corrugated resilient bellows having the upper end thereof fixed to said housing and the other end thereof extending downwardly and surrounding said tube and being secured thereto whereby upon said tube being lifted by said bob weight said bellows is yieldably collapsed to cause the tube to actuate said shut-off switch sensing lever.

Claim 8

Dependent Claim 56 words

The combination set forth in claim 5 wherein said diaphragm means comprises a generally horizontally extending member having a center aperture with said drop line passing therethrough and annular serrations thereon which are adapted to be engaged by the upper end of said weight and to stretch thereagainst during lifting of said tube by said weight.

Claim 9

Dependent Claim 111 words

The combination set forth in claim 4 wherein said actuator means comprises a means interconnecting said weight with said drop line and having an enlargement member fixed thereon spaced above said weight, a diaphragm mounted on said housing and having an aperture through which said drop line extends whereby when the upper end of said weight engages said diaphragm said weight causes said diaphragm to flex, said member having means thereon for engaging said shut-off switch actuating lever and said interconnecting means having a predetermined length such that said member moves said lever from an on to an off position during yielding movement of said diaphragm while engaged by said weight.

Claim 10

Dependent Claim 91 words

The combination set forth in claim 1 including a rotary magnet carrier in said rear chamber, said magnet carrier being operatively connected to said first pulley, a plurality of magnets mounted on said carrier, said magnets extending longitudinally generally tangentially to a circle concentric with and spaced radially outwardly of the center of rotation of said carrier, and a reed switch mounted on said housing in fixed position such that as said carrier rotates each magnet is brought into generally parallel relation to the reed switch to produce a counting signal.

Claim 11

Dependent Claim 41 words

The combination set forth in claim 9 wherein said magnets each comprise longitudinally polarized bar magnets and said reed switch is oriented with its longitudinal axis parallel to the polar axis of each magnet when it sweeps by said reed switch.

Claim 12

Dependent Claim 30 words

The combination set forth in claim 10 including means for mounting said rotary switch comprising a plate mounted on said central portion, said plate having said reed switch adhered thereto.

Claim 13

Dependent Claim 43 words

The combination set forth in claim 1 including means for yieldingly urging said level sensing lever in one direction comprising a torsion spring, means for adjusting the tension of said torsion spring on said lever comprising a plurality of serrations on said housing.

Claim 14

Dependent Claim 51 words

The combination set forth in claim 12 wherein said torsion spring comprises at least one winding with arms extending from the opposite ends of said winding, one of said arms of said torsion spring engaging said level sensing lever, the other of said arms of said torsion spring engaging said serrations.

Claim 15

Dependent Claim 42 words

The combination set forth in claim 13 wherein said serrations extend in a curved row having a radius Of curvature concentric with said spring winding, and wherein said other arm is curved to conform with the curvature of said row of serrations.

Claim 16

Dependent Claim 48 words

The combination set forth in claim 1 including a spool having a helical groove therein and connecting said drop line to said weight, said drop line being wound around said helical groove, said weight having a recess into which said spool extends with the drop line wound thereabout.

Claim 17

Dependent Claim 56 words

The combination set forth in claim 15 wherein said spool includes an axial groove in the outer periphery thereof into which said drop line extends prior to being wound about said spool whereby the turns of said drop line wound in said helical groove overlie the portion of said drop line extending in said axial groove.

Claim 18

Dependent Claim 72 words

The combination set forth in claim 1 wherein said first cover has a pocket therein juxtaposed with said lower front chamber of said housing and defining a portion thereof, said lower chamber having a bottom wall sloping downwardly toward said pocket, the lowermost portion of said pocket being disposed below said wall whereby dirt or other foreign material collecting in said lower chamber tends to migrate to and deposit in said pocket.

Claim 19

Dependent Claim 26 words

The combination set forth in claim 8 wherein upper end of said weight engages said diaphragm to seal said aperture during yielding movement of said diaphragm.

Annuity Stage	Window Opens	Payment Deadline	Surcharge Period Until	Estimated Fee	Status
3.5 Years (Year 4)	1977-09-30	1978-04-01	1978-10-01	$2000.00	Window Closed / Lapsed
7.5 Years (Year 8)	1981-09-30	1982-04-01	1982-10-01	$3760.00	Window Closed / Lapsed
11.5 Years (Year 12)	1985-09-30	1986-04-01	1986-10-01	$7700.00	Window Closed / Lapsed

Material level indicator

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