Earthquake-responsive fuel shut-off device

Claim 2

An earthquake-responsive fuel shut-off device adapted for insertion in a fuel line connected to a fuel source under pressure comprising: a main valve and a fluid-pressure-responsive actuator therefor maintaining said valve in fluid flow open position in response to a fuel-line-imposed pressure differential and including means biasing said valve to flow shut-off position in the absence of said differential; means providing a fluid-line-connected passage to said actuator for placing said line pressure in opposition to and equalizing said pressure differential to effect closing of said valve by said biasing means; a second valve in said passage movable between open and closed positions therein; a spring urging said valve to open position; a member having a position engaged with and supporting said valve in closed position against the urge of said spring; and an earth-movement-responsive actuator connected to and displacing said member from its said position in response to a predetermined minimum severity earthquake, thus permitting opening of said valve.

Claim 3

An earthquake-responsive fuel shut-off device adapted for insertion in a fuel line connected to a fuel source under pressure comprising: a main valve and a fluid-pressure-responsive actuator therefor maintaining said valve in fluid flow open position in response to a fuel-line-imposed pressure differential and including means biasing said valve to flow shut-off position in the absence of said differential; means providing a fluid-line-connected passage to said actuator for placing said line pressure in opposition to and equalizing said pressure differential to effect closing of said valve by said biasing means; a second valve in said passage movable between open and closed positions and biased for movement to open position; a pendulum mounted to swing in response to a predetermined severity earthquake; and means connecting said pendulum and second valve and holding the latter in closed position against its bias in an undisturbed pendant position of said pendulum and releasing said second valve upon predetermined displacement of said pendulum to permit movement of said second valve to open position under its bias and consequent closing of said main valve.

Claim 4

An earthquake-responsive fuel shut-off device adapted for insertion in a fuel line connected to a fuel source under pressure comprising: a main valve and a fluid-pressure-responsive actuator therefor maintaining said valve in fluid flow open position in response to a fuel-line-imposed pressure differential and including means biasing said valve to flow shut-off position in the absence of said differential; means providing a fluid-line-connected passage to said actuator for placing said line pressure in opposition to and equalizing said pressure differential to effect closing of said valve by said biasing means; a second valve in said passage movable between open and closed positions and biased for movement to open position; a pendulum mounted to swing in response to a predetermined severity earthquake; and means connecting said pendulum and second valve and holding the latter in closed position against its bias in an undisturbed pendant position of said pendulum and releasing said second valve upon predetermined displacement of said pendulum to permit movement of said second valve to open position under its bias and consequent closing of said main valve.

Claim 5

A device as defined in claim 1, said pendulum having an arm pivotally mounted in spaced relation to an upper end of said arm; and said second valve having a reciprocating part mounted in abutment with and supported on said arm upper end in said undisturbed pendant position of said pendulum to hold said second valve in closed position, said arm end moving in response to a predetermined minimum severity earthquake to release said part.

Claim 6

A device as defined in claim 3, said valve part being movable on a vertical axis coincident with the undisturbed vertical axis of said arm and between a relatively elevated closed position of said valve and a lower open position of said valve, said part being normally supported in its elevated position on the upper end face of said arm but in sliding contact therewith, thus permitting arcuate sliding displacement of said face out of supporting contact with said part.

Claim 7

A device as defined in claim 4, said end face having a convex form facilitating said sliding engagement.

Claim 8

A device as defined in claim 5, and a plurality of members formed for interchangeably mounting on said arm end and providing end faces of different sizes functioning to release said part in response to earth movements of different severities.