Fail-safe valve assembly for power chuck motors and the like

Claim 2

A fail-safe rotatable valve assembly for reversible power chuck motors and the like comprising a valve housing defining first and second passages; means mounting said valve housIng for rotation; means for exposing said passages to a source pressure and to an exhaust pressure, respectively; means for reversing the exposure so that the passages are exposed to exhaust and source pressure, respectively; free floating check valve means in said passages; check valve seats in said passages for said check valve means positioned relative the valve means such that centrifugal force resulting from rotation of the valve housing biases the valve means against the valve seats; an actuating means for engaging and holding each said check valve means spaced from its associated valve seat; and means for energizing each actuating means when the passage and check valve means associated therewith are exposed to exhaust reference pressure for thereby opening said passage.

Claim 3

The valve assembly of claim 1 wherein each actuating means is a member movable to engage the check valve means and to dislodge the valve means from its associated valve seat, each actuating means being movable radially in said valve housing and positioned relative to the check valve means such that centrifugal force resulting from rotation of the valve housing biases the actuating means away from and out of engagement with the check valve means.

Claim 4

The valve assembly of claim 2 wherein each actuating means is a piston actuator including a stem means aligned with movement of the check valve means arranged to engage the latter, said valve housing including means for communicating each piston actuator with source pressure when the check valve means associated therewith is exposed to reference exhaust pressure, said source pressure energizing the actuating means.

Claim 5

The valve assembly of claim 3 wherein said check valve means are ball valves.

Claim 6

The valve assembly of claim 4 including valve chambers in which said check valve means are movable, said valve chambers being radially bored openings in said valve housing extending from the outer periphery of the housing into communication with the passages in said housing, each chamber comprising an insert therein forming said valve seats, the inserts having radially extending openings through which the piston actuator stem means extend, said piston actuators being movable in said radially bored openings outboard of said inserts.

Claim 7

The valve assembly of claim 3 including means in said valve housing communicating the reference exhaust pressure with that piston actuator associated with the check valve means exposed to source pressure whereby the piston actuator is freely movable out of engagement with the check valve means.

Claim 8

A rotatable fail-safe motor valve assembly including a motor housing and reciprocable piston means therein; a valve housing including first and second passages communicating with opposite sides of said piston means; means mounting said motor housing and said valve housing for rotation; means for exposing said passages to a source pressure and an exhaust pressure respectively; means for reversing the exposure so that the passages are exposed to exhaust and source pressure, respectively; separate valve chambers for each of said passages, the improvement comprising free floating check valve means movable in said chamber; valve seats for said check valve means to close said chambers; said valve seats being positioned relative the check valve means whereby centrifugal force on the valve means biases the latter against the valve seats; an operator means for engaging said valve means to dislodge each said valve means from the respective valve seat, each said operator means also being biased radially outward away from the valve means by centrifugal force acting thereon; and means for exposing either of said operator means to said source pressure when the valve means associated therewith is exposed to exhaust pressure thereby energizing the operator means into engagement with said check valve means.

Claim 9

A rotatable fail-safe motor valve assembly including a motor housing and reciprocable piston means therein; a valve housing including first and second passages communicating with opposite sides of said piston means; means mounting said motor housing and said valve housing for rotation; means for exposing said passages to a source pressure and an exhaust pressure respectively; means for reversing the exposure so that the passages are exposed to exhaust and source pressure, respectively; separate valve chambers for each of said passages, the improvement comprising free floating check valve means movable in said chamber; valve seats for said check valve means to close said chambers; said valve seats being positioned relative the check valve means whereby centrifugal force on the valve means biases the latter against the valve seats; an operator means for engaging said valve means to dislodge each said valve means from the respective valve seat, each said operator means also being biased radially outward away from the valve means by centrifugal force acting thereon; and means for exposing either of said operator means to said source pressure when the valve means associated therewith is exposed to exhaust pressure thereby energizing the operator means into engagement with said check valve means.

Claim 10

An assembly according to claim 7 further Including means for exposing the exhaust reference pressure to the operator means associated with the valve means exposed to source pressure to thereby permit such operator means to move radially outward away from the valve means when centrifugal force acts thereon.

Claim 11

A rotatable fail-safe valve assembly for reversible power chuck motors and the like comprising a valve housing defining first and second passages; means mounting said valve housing for rotation; means for exposing said passages to a source pressure and an exhaust reference pressure, respectively; means for reversing said exposures; free floating check valve means in said passages; check valve seats in said passages for said check valve means positioned relative the valve means such that centrifugal force resulting from the rotation of the valve assembly biases the valve means against the valve seats; an actuating means for engaging and holding each said check valve means spaced from the respective valve seat; and means for exposing either of said actuating means to said source pressure when the valve means associated therewith is exposed to exhaust reference pressure, thereby spacing the associated valve means from its valve seat, and means for disassociating the other of said actuating means from said source pressure whereby the valve means associated therewith is free to move against its valve seat from said centrifugal force. 10 A fail-safe rotatable valve assembly for reversible power chuck motors and the like comprising a valve housing defining first and second passages; means mounting said valve housing for rotation; means for exposing said passage to a source pressure and to an exhaust pressure, respectively; means for reversing said exposure; free floating check valve means in said passages; check valve seats in said passages for said check valve means positioned relative the valve means such that centrifugal force resulting from the rotation of the valve housing biases the valve means against the valve seats; an actuating means for engaging and holding each said check valve means spaced from the associated valve seat; and means for exposing either of the actuating means to said source pressure when the valve means associated therewith is exposed to exhaust reference pressure, and for exposing the other of said actuating means to exhaust reference pressure when the valve means associated therewith is exposed to source pressure.

Claim 12

A rotatable fail-safe valve assembly for reversible power chuck motors and the like comprising a valve housing defining first and second passages; means mounting said valve housing for rotation; means for exposing said passages to a source pressure and an exhaust reference pressure, respectively; means for reversing said exposures; free floating check valve means in said passages; check valve seats in said passages for said check valve means positioned relative the valve means such that centrifugal force resulting from the rotation of the valve assembly biases the valve means against the valve seats; an actuating means for engaging and holding each said check valve means spaced from the respective valve seat; and means for exposing either of said actuating means to said source pressure when the valve means associated therewith is exposed to exhaust reference pressure, thereby spacing the associated valve means from its valve seat, and means for disassociating the other of said actuating means from said source pressure whereby the valve means associated therewith is free to move against its valve seat from said centrifugal force. 10 A fail-safe rotatable valve assembly for reversible power chuck motors and the like comprising a valve housing defining first and second passages; means mounting said valve housing for rotation; means for exposing said passage to a source pressure and to an exhaust pressure, respectively; means for reversing said exposure; free floating check valve means in said passages; check valve seats in said passages for said check valve means positioned relative the valve means such that centrifugal force resulting from the rotation of the valve housing biases the valve means against the valve seats; an actuating means for engaging and holding each said check valve means spaced from the associated valve seat; and means for exposing either of the actuating means to said source pressure when the valve means associated therewith is exposed to exhaust reference pressure, and for exposing the other of said actuating means to exhaust reference pressure when the valve means associated therewith is exposed to source pressure.