Jet Level Sensor

Abstract

This disclosure relates to a sensor for operating a flow control valve pilot. The sensor incorporates a jet which is interrupted by rising liquid within a container and includes an aspirator for picking up liquid and deflecting the jet to render same ineffective.

Description

This invention specifically relates to the addition of an aspirator to a jet level sensor to effect deflection of a control jet as opposed to resistance to flow by rising liquid whereby a higher jet pressure may be utilized for more effective control.

Previously jet level sensors have been provided for automatically actuating pilots of filling valves to effect automatic shutoff when liquid reaches a predetermined level. These sensors employ a liquid jet directed across a void to a receiver with the jet being interrupted by liquid rising within the void. Prior sensors were limited to 20 p.s.i. pressures in that higher pressure jets are not sufficiently affected by the presence of intervening liquid.

Jet level sensors may operate at pressures as high as 150 p.s.i. by providing an aspirator at the discharge end of a jet nozzle for drawing rising liquid transversely across a flowing jet to deflect same from its normal path to a receiver. Such sensors do not rely upon the presence of intervening liquid to disrupt jet flow and are not of limited operating pressure.

With the above and other objects in view that will hereinafter appear, the nature of the invention will be more clearly understood by reference to the following detailed description, the appended claims and the several views illustrated in the accompanying drawing:

In the drawing:

FIG. 1 is a schematic sectional view through a tank having level control filling mechanism.

FIG. 2 is an enlarged schematic sectional view showing control valve operated by the sensor.

FIG. 3 is an enlarged sectional view through the sensor.

A typical tank filling system is shown in FIG. 1 as including tank 5 having filler conduit 6 connected to an inlet of shutoff valve 7. Jet level sensor 8, positioned at a desired level in tank 5, is connected to conduit 6 by supply line 9 and to pilot 10 of valve 7 by pilot line 11.

Details of typical shutoff valve 7 are found in FIG. 2. Valve 7 has pressure controlled diaphragm mounted valve member 12 controlling flow from conduit 6 into tank 5. Small passage 13 in valve member 12 permits pressure build up above valve member 12 to close same.

Pilot 10 controls pressure above valve member 12 and includes vent 14, which is larger than passage 13, controlled by pilot valve member 15 constantly urged to closed position by spring 16. Pressure controlled diaphragm mounted piston 17 is connected to valve member 15 for unseating same in response to pressure exerted on piston 17 through pilot line 11.

Details of new sensor 8 are shown in FIG. 3 as including housing 20 having central opening 21. Bore 22 extends through housing 20 with fitting 23 of supply line 9 threaded in one end and end portion 24 at other end opening into opening 21. Central portion of bore 22 is restricted to form jet nozzle 25. Housing 20 has aspirator 26 in form of a bore opening upwardly into end portion 24 for drawing liquid in tank 5 into end portion 24 by flowing liquid jet.

Housing 20 has bore 27 on opposite side of housing 21 from bore 22 aligned with bore 22. Receiver 28 is mounted in bore 27 at opening 21 for receiving liquid jet from jet nozzle 25. The opposite end of bore 27 has threaded therein fitting 29 of pilot line 11 to direct jet pressure into pilot 10.

Tank 5 is filled by coupling to adapter 30 thereof, carried by conduit 6, filling nozzle 31, and initiating flow by turning control handle 32 (FIG. 2). Liquid flows through line 9 to sensor 8 to apply pilot opening pressure to piston 17 through line 11, venting space in valve 7 above valve member 12 through vent 14.

Liquid entering valve 7 from conduit 6 moves valve member 12 to open position and flows through opening 33 in valve 7 into tank 5. Flow into tank 5 continues until liquid reaches sensor 8 at which time jet flow from nozzle 25 to receiver 28 is disrupted and pressure on piston 17 is reduced, permitting spring 16 to move valve member 15 to block flow from passage 13 to vent 14. Pressure in valve 7 above valve member 15 moves valve member 15 to closed position to stop flow into tank 5.

In prior sensors flow of liquid into opening 21 was relied upon to disrupt jet flowing from jet nozzle 25 into receiver 28. This provided an effective control when liquid delivered to sensor had a maximum pressure of 20 p.s.i. Increased pressures permit jet flow through liquid in opening 21 sufficiently to prevent difficulties in obtaining assured accurate control of pilot 10.

Aspirator 26 permits flow of liquid jet through end portion 24 to draw liquid, which has reached sensor level, into end portion 24 normal to axis of jet flow. Aspirated liquid, striking liquid jet at right angles to axis of flow, deflects liquid jet sufficiently to miss small entrance of receiver 28. Thus, liquid at higher pressures may be directed to sensor 8 without effecting efficient operation thereof. Pressure of liquid directed to sensor 8 may be that of liquid in conduit 6 which may be on the order of 150 p.s.i. and higher.

Although only a single embodiment of sensor has been illustrated and described, it is to be understood that minor modifications may be made therein without departing from the spirit of the invention.

Claims

I claim:

1. A jet sensor particularly adapted to detect the pressure of liquid, said sensor comprising a jet nozzle for directing a jet flow of liquid along a predetermined axis, a receiver spaced from said jet nozzle and aligned with the axis of jet flow therefrom the receiving a jet flow from said jet nozzle to maintain a pressurized control, and means for directing detected liquid transversely of the axis of said jet nozzle against jet flow therefrom to deflect such jet flow away from said receiver and thus remove the pressurized control.

2. The jet sensor of claim 1 wherein said means for directing detected liquid are aspirator means.

3. The jet sensor of claim 1 wherein said means for directing detected liquid are aspirator means effected by jet flow from said jet nozzle.

4. The jet sensor of claim 1 wherein said means for directing detected liquid are aspirator means, said aspirator means including an axial bore into which said jet nozzle opens and a transverse bore opening into said axial bore adjacent said jet nozzle.

5. The jet sensor of claim 1 wherein said sensor is a liquid level sensor.

6. The jet sensor of claim 1 wherein said sensor is a liquid level sensor and said sensor is part of a container filling apparatus.

7. The jet sensor of claim 1 wherein said sensor is a liquid level sensor and said sensor is part of a container filling apparatus, said apparatus including a filler conduit, a shutoff valve controlling flow from said filler conduit into the container, said shutoff valve having a pilot control connected to and positioned by said sensor, and said sensor being connected to said filler conduit for effecting the jet flow thereof.