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US8688461B1
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Electronic registry for authenticating transferable records
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US4335733A
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Valve for use in handling abrasive materials and method of wear prevention
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US4281280A
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Thermal electric converter
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US4384659A
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Apparatus and method for pumping powdered material
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US4036564A
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Concrete pumping apparatus
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US3238392A
|
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Moisture-governed automatic control for irrigation system
|
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US3228524A
|
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Backwashing control for multipleseptum filter bed
|
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US3138552A
|
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Means for backwashing a filter bed
|
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US3139628A
|
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Automatic water refill system for swimming pool
|
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US3040469A
|
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Minnow pail water changer
|
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US3039698A
|
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Automatic control for sprinkler system
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US1962524A
|
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Routing machine
|
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US1870466A
|
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Combination saw planer and planer for printers' use
|
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US1723077A
|
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Circular-saw structure
|
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US1006277A
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Rule-cutting machine.
|
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CA606886A
|
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Minnow pail water changer
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CA709217A
|
|
Means and method for backwashing filter bed
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