Abstract:
A remotely operated safety valve is provided for terminating flow through the valve. The safety valve includes an electromagnet for holding the safety valve open, and a swing plate for closing the safety valve. A power supply is provided for powering the electromagnet, and an electrical conductor extends between the shutdown switch, the power supply, and the electromagnet. A connector spaced along the conductor is separable during a separation of a towing vehicle from the towed vehicle. The safety valve automatically closes in response to one of activation of the shutdown switch or the termination of power to the electromagnet.

Description:
FIELD OF THE INVENTION 
     The present invention relates to emergency shutoff valves and, more particularly, to remotely actuated manually reset shutoff valves which provide essentially no flow restriction when open. 
     BACKGROUND OF THE INVENTION 
     Various types of shutoff valves have been proposed, including the valve disclosed in U.S. Pat. No. 7,036,441. The valve disclosed in this patent allows an operator to close the valve manually in the event of an emergency by pulling on a cable routed in close proximity of the operator, or automatically shuts the valve if the cable, which is typically attached to a vehicle towing the implement carrying the valve, is pulled by virtue of the towing and towed vehicle becoming disconnected or un-hitched. The &#39;441 patent uses a spring loaded ball valve for closure which, when open, provides very little restriction to flow. The closure system uses a cable attached to a pin that releases the spring loaded ball valve when pulled. The cable, however, is difficult to adapt for both automatic and manual closure of the valve. This is because a cable routed for good automatic operation cannot easily be routed to the towing vehicle cab for operator manual operation. Similarly, a cable routed for good operator manual operation cannot be routed for proper automatic operation in the case of a vehicle un-hitch event. In addition, when the valve is left open for long periods, sticking associated with spring loaded ball valves becomes a problem affecting the reliability of the system. 
     The cable constraints and sticking ball valve issues of the &#39;441 patent are overcome by the electrical release system disclosed in Nimberger U.S. Pat. No. 7,401,562 which discloses a poppet style valve. The poppet style shutoff valve, however, undesirably introduces significant flow restriction when the valve is open. 
     The disadvantages of the prior art are overcome by the present invention, an improved remotely operated shutoff valve is hereinafter disclosed. 
     SUMMARY OF THE INVENTION 
     A disk style shutoff valve eliminates significant flow restrictions when open, and resolves the sticking problems associated with spring loaded ball valves. Several embodiments of electrically operated mechanisms are disclosed that provide both “hold open” and release functionality. 
     The shutoff valve uses a swing style check disk held in the open position by an actuation pin situated close to the pivot point of the disk, such that a relatively small linear movement of the actuation pin will swing the disk from a closed position through approximately 90 degrees to an open position, and will hold the disk in the open position until the linear force on the actuation pin is removed. Several embodiments for sustaining and removing the linear force on the actuation pin are disclosed. 
     One embodiment utilizes a “U” shaped member that allows manual opening of the valve. When open, an electromagnet captures one end of the “U” shaped member, keeping the valve open until power is removed from the electromagnet which allows the spring biased “U” shaped member to release the actuation pin and close the valve. 
     Another embodiment involves a slightly different concept wherein the actuation pin that opens the valve is manually pushed to an open position without being connected to the release mechanism. With the disk in the open position, a constraint pin is inserted in a hole formed in the disk member by activation of an electric solenoid. The constraint pin holds the disk open until the solenoid power is removed. The spring biased constraint pin retracts from the hole in the disk and allows the valve to close. 
     Still another embodiment opens the valve manually by pushing on the actuation pin, as in the above embodiment. Once open, the disk is then held open by an energized electromagnet which comes into contact with the disk in the open position. An integrated proximity sensor provides open/closed status information and the disk can be released by dropping power to the electromagnet. 
     A feature of these embodiments is the combination of electrical hold open and release functionality with a valve that has essentially no flow restriction when open and no closure sticking tendencies when actuated. Another feature is the electrical feedback provided to indicate if the valve is latched open or not. 
     These and further features and advantages of the present invention will become apparent from the following detailed description, wherein reference is made to the figures in the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an isometric view of a preferred embodiment of a shutoff valve with the cover removed. 
         FIG. 2  is a side cross-sectional view of  FIG. 1 . 
         FIG. 3  is a top cross-sectional view of  FIG. 1  through section  2 - 2  of  FIG. 2 . 
         FIG. 4  is an isometric view of another embodiment. 
         FIG. 5  is a cross-sectional view of  FIG. 4  through section  5 - 5  with the valve open. 
         FIG. 6  is a cross-sectional view of  FIG. 4  through section  5 - 5  with the valve closed, and showing the open position in dashed lines. 
         FIG. 7  is a cross-sectional view of  FIG. 4  through section  7 - 7  with the valve closed. 
         FIG. 8  is a cross-sectional view of  FIG. 4  through section  7 - 7  with the valve open. 
         FIG. 9  is an isometric view of another embodiment. 
         FIG. 10  is a cross-sectional view of  FIG. 9  through section  10 - 10  with the valve open. 
         FIG. 11  is a cross-section view of  FIG. 9  through section  10 - 10 , showing the position of the swing disk in both the open and closed positions, and showing the valve open position in dashed lines. 
     
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
       FIG. 1  is an isometric view of an emergency shutoff valve with the actuator compartment cover removed and ancillary system components. The valve includes a valve body  1 , actuator compartment base  2 , pressure bleed fitting  3 , product outlet port  4  and product inlet port  5 . The actuator assembly is composed of “U” shaped member  6  which is connected to actuator hold plate  7  and restrained by guide member  8 , each fixed relative to the valve body  1 . The electrical components consist of electromagnet  9 , latch indicator relay  10 , and electrical harness  11  which contains cover penetration cable restraint  12 , connector  13 , power wire  14  and relay wire  15 . The ancillary electrical components are battery power source  62  and primary manual kill switch  63  both of which are typically located on a towing vehicle  64 . Primary kill switch  63  contains the kill actuator  65  and the latched indicator light  66 . Extending from the towing vehicle, the electrical circuit may contain one or more manual kill actuators  67  in addition to a pull-to-disconnect connector  68 . Flow outlet line  69  generally follows the electrical harness to supply product some device located on the towing vehicle  64 . 
       FIG. 2  is a side cross-sectional view of  FIG. 1 . The valve is opened by applying manual force to the surface  16  of actuator member  6 . End  17  of member  6  moves actuation pin  18  to engage surface  19  of disk assembly  20 , which swings the disk assembly to the open position. Surface  19  of disk assembly  20  and thus pin  18  are located very close to the pivot point  26  of disk assembly  20 , such that a relatively small linear movement of actuation pin  18  will move the disk assembly from full closed to full open. The other end of member  6  is attached to hold plate  7  which is brought into contact with electromagnet  9 , which holds the valve open when the electromagnet is energized. The latching mechanism is protected from the elements by cover  21 . The electromagnet is attached to the base plate  2  by bracket  22 . With the electromagnet energized and the valve in the open position, fluid is free to flow in an unobstructed manner from inlet port  5  to outlet port  4 . 
       FIG. 3  is a top view of  FIG. 1  showing the position of latching indicator relay  10  which is closed electrically when plate  7  is contacting electromagnet  9 . This latching relay is connected via the wiring harness  11  to one or more electrical actuation points  63  and  67  where the closed latching relay is used to light a latching indicator light  66  and where power to the electromagnet can be interrupted, causing the valve to close. 
     The electrical harness can also be arranged between a towing and towed vehicle such that if a towing disconnection occurs between the two vehicles, the electrical harness will pull apart at a connection point  68  which will disconnect the electromagnet from the power source, typically the battery  62  of the towing vehicle. This will de-energize the electromagnet, allowing the valve to swing to a closed position thus achieving “automatic” closure in the un-hitching situation. The closing force is provided by disk biasing spring  23  and pin  18  biasing spring  24  when the electromagnet power is removed. Once the disk assembly  20  is partially closed, the flow of product through the valve will move it to its fully closed position against resilient seat ring  25 . 
       FIG. 4  is an isometric view of another embodiment. The body  1 , inlet port  5  and outlet port  4  are identical to the previous embodiments. The valve is opened by manually pressing on push tab  40  which is fixed to the end of actuation pin  18 . Once the valve is opened manually, solenoid assembly  41  is actuated to hold the valve in the open position. 
       FIG. 5  is a cross-sectional view of  FIG. 4 . With actuation pin  18  in the open position, the solenoid assembly  41  is energized which extends hold pin  42  into cavity  43  on disk assembly  20  such that when force is removed from push tab  40 , the actuator pin biasing spring  24  moves the pin  18  to the spring bias position clear of engagement with disk assembly  20 , and keeping the solenoid assembly  41  energized such that the disk assembly  20  will be held open by hold pin  42 . When the solenoid  41  is de-energized, hold pin  42  will withdraw from cavity  43  on disk assembly  20 , allowing the disk assembly  20  to move to its closed position assisted by product flow and the disk bias spring  23 , as shown in  FIG. 6 . The open position of the disk assembly  20  is shown in dashed lines in  FIG. 6 . 
       FIG. 7  is a cross sectional view of solenoid assembly  41 . When electromagnet  45  is energized, hold pin  42  is moved to its extended position as shown in  FIG. 7  which also compresses return spring  44 . When power is removed from electromagnet  45 , hold pin return spring  44  forces hold pin  42  to its retracted position, allowing disk assembly  20  to close, as shown in  FIG. 8 . Momentary open button  46  located on solenoid assembly  41  is provided to interrupt the power to the solenoid when depressed to retract hold pin  42 , while push tab  40  is used to move the disk assembly  20  to its open position. While disk assembly  20  is held open, momentary open button  46  is released which closes the power circuit in power harness  47 . The energized electromagnet  45  moves hold pin  42  into cavity  43  to hold the disk assembly  20  in the open position. If power is then interrupted in harness  47  by vehicle separation, the valve will automatically close. 
       FIG. 9  is an isometric view of another embodiment. The body  1 , inlet port  5  and outlet port  4  may be identical to the previous embodiments. The valve is opened by manually pressing on push tab  48  which is fixed to the end of actuation pin  18 . Once the valve is opened manually, electromagnet assembly  49 , which penetrates and is mounted to body  1 , is actuated to hold the valve in the open position. Disk assembly  20 , similar the previous embodiments, is modified slightly to include magnetic catch plate  49  attached to disk assembly  20  by screw  50 . The catch plate provides a surface highly permeable to magnetic flux such that when electromagnet  51  is energized, the catch plate  49  is held firmly to the face of electromagnet  51 . Proximity sensor  52  is integral to the electromagnet assembly  59  and allows the close proximity of the latch plate  49  to be detected and used to illuminate a “latched open” light  66  at any point along the power circuit. When power is removed from electromagnet  51 , the magnetic latch plate  49  is released allowing the disk assembly  20  to move to the closed position as shown in  FIG. 11 . 
     The advantages of moving the drive pin linearly to hold the swing plate open are twofold:
         (1) The linear push on the pin does not involve a wear point as is the case with a cam, and   (2) The required movement of the hold-open device for pushing the pin is much less than that required to rotate the cam through at least 45 degrees. In the direct push method, the actuator latch plate moves the same amount as the drive pin. In the cam situation, the latch plate moves considerably farther as it swings and requires more space, and therefore cost, to accommodate the swing motion.       

     Another embodiment for sustaining and removing the linear force on the actuation pin utilizes a cam shaped member affixed to a rotatable shaft. The shaft is manually rotated to apply linear force on the actuation pin and open the valve. A second member affixed to the shaft is captured by an electromagnet in the full open position and holds the valve open until power is removed from the electromagnet, thereby allowing the spring biased shaft to rotate and thereby remove force from the actuation pin and allow the valve to close. A cam shaped member may be rotated about cam shaft to apply linear force on actuator pin to open the disk assembly. The valve may be opened by manually rotating the cam shaft against the biasing spring. The cam shaft is fixed to magnetic latching assembly composed of a holding member attached to arm. When holding member is manually rotated into contact with electromagnet, the valve will remain open until power is removed from electromagnet, allowing the biasing spring to rotate the cam member out of engagement with actuation pin, thereby allowing the disk assembly to swing to the closed position. The position of handle visually indicates the open or closed condition of the valve and an indicator relay may be used to contact the arm in the open position to electrically indicate the relay open or closed condition throughout the system. 
     A feature of the emergency shutoff valve is the fail safe nature of the release mechanism. The valve closes on loss of power. A related feature is the ability of the release circuit to easily be adapted for automatic or multipoint manual activation. The spring biased actuation pin is located such that a small linear movement of the actuation pin may fully open the valve 
     Although specific embodiments of the invention have been described herein in some detail, this has been done solely for the purposes of explaining the various aspects of the invention, and is not intended to limit the scope of the invention as defined in the claims which follow. Those skilled in the art will understand that the embodiment shown and described is exemplary, and various other substitutions, alterations and modifications, including but not limited to those design alternatives specifically discussed herein, may be made in the practice of the invention without departing from its scope.