Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
155 words
A fail safe valve operator, comprising: a valve body having a valve seat therein; a valve member mounted in the valve body for movement toward and away from the valve seat to closed and open positions, respectively; a valve stem connected with the valve member to move the valve member between its open and closed positions; motor means operatively connected with the valve stem to operate it to one of said positions; clutch means connected between the motor means and valve stem to selectively engage and disengage the motor means from the valve stem; and spring means connected with the valve stem so that when said valve stem is operated to its said one position energy is stored in the spring means, and when said clutch means is disengaged to disengage said motor means from the valve stem, the spring means acts on the valve stem to return the valve member to its other position.
Claim 2
Dependent Claim
155 words
A fail safe valve operator, comprising: a valve body having a valve seat therein; a valve member mounted in the valve body for movement toward and away from the valve seat to closed and open positions, respectively; a valve stem connected with the valve member to move the valve member between its open and closed positions; motor means operatively connected with the valve stem to operate it to one of said positions; clutch means connected between the motor means and valve stem to selectively engage and disengage the motor means from the valve stem; and spring means connected with the valve stem so that when said valve stem is operated to its said one position energy is stored in the spring means, and when said clutch means is disengaged to disengage said motor means from the valve stem, the spring means acts on the valve stem to return the valve member to its other position.
Claim 3
Dependent Claim
98 words
A device as described in claim 1, wherein said motor means includes a rotary drive means connected to move the valve stem, said spring means comprising clock spring means having one end attached to the drive means for exerting a rotary foRce thereon, whereby said clock spring is wound when the motor means is connected through the clutch means to move the drive means to move the valve member to its said one position, and when the clutch means is disengaged, the prewound clock spring rotates the drive means to move the valve stem to its other position.
Claim 4
Dependent Claim
45 words
The valve stem operator as described in claim 2 wherein said motor means is coupled to said clutch through a worm gear drive such that the clock spring cannot rotate the drive means when the clutch is engaged, even when the motor is not actuated.
Claim 5
Dependent Claim
41 words
A device as described in claim 2 and wherein said clutch has a selective clutch shifter mechanism which is powered by a fluid cylinder to engage the clutch and which is biased to disengage the clutch when the cylinder is deactivated.
Claim 6
Dependent Claim
20 words
A device as described in claim 1 and wherein said clock spring means includes a plurality of clock spring elements.
Claim 7
Dependent Claim
25 words
A device as described in claim 1 wherein said rotary drive means is coupled to said valve stem through a low friction ball jack nut.
Claim 8
Dependent Claim
26 words
A device as described in claim 1 and wherein said rotary drive means, clock spring means and clutch means are coaxially aligned around said valve stem.