Thief hatch

Abstract

The disclosure provides systems and methods of manufacturing pertaining to an improved thief hatch. One embodiment provides a base, a cap, and an actuating mechanism disposed between the base and the cap. The base includes an annular lip that defines an opening that is configured to attach above an opening of a storage container such that the openings of the base and the container share a longitudinal center axis. The actuating mechanism is indirectly coupled to a seal such that in the resting position, the biasing mechanism exerts a biasing force on the seal toward the annular lip of the base to create a sealed connection. At least one structural constraint may protrude from the interior surface of the cap in a manner that prevents lateral movement of the actuating mechanism such that it moves exclusively along the longitudinal axis and cannot toggle during operation. Other embodiments are also disclosed.

1 . A thief hatch configured to couple with a storage container having an opening, said thief hatch comprising:
 a base configured to affix to the storage container, said base comprising an annular lip that defines an opening, wherein said opening of said base and the opening of the storage container share a longitudinal center axis;   a cap coupled to said base;   a seal disposed between said base and said cap;   an actuating mechanism disposed on an interior surface of said cap, said actuating mechanism configured to exert a biasing force on said seal to bias said seal against said annular lip of said base; and   at least one structural constraint configured to prevent lateral movement of said actuating mechanism such that said actuating mechanism moves exclusively along said longitudinal center axis.   
     
     
         2 . The thief hatch of  claim 1 , wherein said cap is coupled to said base via a spring configured to enable said cap to rotate about said base between closed and open positions, and wherein said spring is configured to bias said cap toward said open position. 
     
     
         3 . The thief hatch of  claim 2 , wherein a latch releasably secures said cap to said base, and wherein said latch is configured to engage with a latch pin of said base when said cap is in said closed position. 
     
     
         4 . The thief hatch of  claim 1 , wherein said structural constraint comprises a pin protruding from said interior surface of said cap. 
     
     
         5 . The thief hatch of  claim 4 , wherein said actuating mechanism comprises a compression spring configured to generate said biasing force. 
     
     
         6 . The thief hatch of  claim 5 , further comprising:
 a structural insert configured to enclose a first end of said compression spring, said insert having at least one retention tab; and   an insert sleeve protruding from said interior surface of said cap and configured to enclose a second end of said compression spring, said insert sleeve configured to receive and retain said structural insert such that said compression spring is nested therein, wherein said insert sleeve comprises a helical groove configured to guide said retention tab into a longitudinal recess adapted to retain said retention tab and allow said structural insert and said compression spring to move along said longitudinal center axis.   
     
     
         7 . The thief hatch of  claim 6 , wherein an edge of said pin aligns with a vertex of said helical groove and said longitudinal recess, thereby preventing movement of said structural insert and said compression spring in a lateral direction. 
     
     
         8 . The thief hatch of  claim 6 , wherein a height of said longitudinal recess defines a longitudinal travel distance of said compression spring and, therefore, of said seal. 
     
     
         9 . The thief hatch of  claim 6 , wherein said pin is installed on said cap via a threaded coupling, a press fit, or an adhered coupling. 
     
     
         10 . A system for venting pressure from an interior of a storage container, comprising:
 a base having an annular lip defining a central opening about a longitudinal axis, said central opening configured to be in fluid communication with the interior of the storage container;   a cap rotatively coupled to said base; and   a seal assembly disposed between said base and said cap, wherein said seal assembly comprises a seal indirectly coupled to an actuating mechanism that is configured to exert a biasing force on said seal toward said annular lip, and wherein said seal assembly is configured such that said actuating mechanism moves exclusively along said longitudinal axis between a closed position in which said seal blocks said central opening and an open position in which said seal is retracted from said central opening.   
     
     
         11 . The system of  claim 10 , wherein said actuating mechanism moves between said open and said closed positions in response to pressure fluctuations within the interior of the storage container. 
     
     
         12 . The system of  claim 11 , wherein said actuating mechanism comprises a compression spring, and wherein when said seal is in said open position, said compression spring is in a compressed state. 
     
     
         13 . The system of  claim 12 , wherein said seal assembly further comprises a structural constraint configured to limit movement of said compression spring to said longitudinal axis. 
     
     
         14 . The system of  claim 13 , wherein said structural constraint comprises a pin protruding from an interior surface of said cap. 
     
     
         15 . The system of  claim 14 , wherein said pin is installed on said cap via a threaded coupling, a press fit, or an adhered coupling. 
     
     
         16 . The system of  claim 14 , wherein said seal assembly further comprises a shell configured to enclose and manipulate said compression spring, said shell comprising:
 a structural insert having at least one retention tab and configured to enclose a first end of said compression spring; and   a mating sleeve configured to receive a second end of said compression spring, wherein said sleeve includes a helical groove configured to guide said retention tab of said structural insert into a longitudinal recess adapted to retain said retention tab and allow said insert and said compression spring to move along said longitudinal axis.   
     
     
         17 . The system of  claim 16 , wherein an edge of said pin aligns with a vertex of said helical groove and said longitudinal recess, thereby preventing lateral movement of said structural insert and said compression spring. 
     
     
         18 - 20 . (canceled)