US2021655A

US2021655A - Safety device

Info

Publication number: US2021655A
Application number: US759377A
Authority: US
Inventors: James A Jonas
Original assignee: Individual
Current assignee: Individual
Priority date: 1934-12-27
Filing date: 1934-12-27
Publication date: 1935-11-19
Anticipated expiration: 1952-11-19

Description

J. A. JONAS SAFETY DEVICE Nov. 19, 1935.

' Filed Dec.

INVE TOR wfl ATTO 7 rue Patented Nov. 19, 1935 UNITED STATES PATENT OFFICE 3 Claims.

This invention relates to an electrically controlled device for exhausting liquid from a storage tank and, more particularly, to a safety device for opening the electrical circuit when the liquid in the tank has fallen below a critical point.

I have described my invention herein in connection with a tank for storing a volatile, electrically non-conducting liquid such as oil, and have provided electrically controlled means for removing water settling to the bottom of the tank. The control means comprises a circuit including two electrodes positioned adjacent the bottom of the tank, across which a circuit is closed when the water in the tank rises into contact with said electrodes. While there is oil on top of the water in the tank, there is little danger arising from any sparking which may occur at the electrodes when a circuit thereacross is either made or broken. However, as is well known, if a volatile liquid such, for example, as gasoline is exhausted from the tank, leaving fumes therein, the danger of explosion due to such sparking is very great. Such sparking may occur, for example, due to dirt or any foreign matter deposited on the electrodes. In order to avoid this dangerous condition and prevent the explosive fumes from coming in contact with the said electrodes, I have provided a means controlled by the level of the liquid in the tank to break the said electric circuit Whenever the liquid in the tank falls below a predetermined point.

Other objects and advantages of the invention will appear from the following description and the claims appended thereto, and the invention may best be understood if the description is read in connection with the accompanying drawing, in which:

Fig. 1 is a vertical cross-section of a tank equipped with my device; and

Fig. 2 is a detail view on an enlarged scale of a contact switch.

As illustrated herein, the storage tank I is provided with a mainoutlet pipe 2 for withdrawing oil from the tank, the orifice of which is positioned somewhat above the bottom of the tank and the outlet 3, preferably positioned at the bottom of the tank, through which water collecting in the tank may be withdrawn. The outlet passage 3 is controlled by the outlet valve 4 normally maintained in closed position by the spring 5.

Depending through an aperture in the top of the tank I is a shaft 6 adjacent the lower end of which is mounted an adjustable spacing member 1, the position of which on the shaft 6 may be adjusted by means of an adjusting screw 8 to position the end of the shaft 6 at the desired distance from the bottom of the tank I. Depending from the bottom of the shaft 6 are the two electrodes 9a and 9b, the upper ends of which 5 are connected respectively to the wires I0 and I I contained within the shaft 6. The wire I 0 extends through the upper end of the shaft 6 to the source of power I2. The wire II is connected at its upper end to the metal sleeve I3 surrounding 10 the upper end of the shaft I5, sleeve I3 also contacting with the arm I4 of the contact switch I 5, carrying the twov contacts I 5a and I5b.

At its top, tank I has an externally threaded lip portion 20 adapted to receive the internally 15 threaded collar 2I surrounding the shaft 6. Mounted on the collar 2I is an upright 22, having pivotally mounted thereon the arm 23 which, in raised position, is adapted to close a circuit across the contacts I5a and I5b. Extending zo around the shaft 6 is a sleeve 24 having at its lower end a float 25 and at its upper end the finger 26 extending through the hollow boss 21 carried by the collar 2|. The finger 26 normally contacts with the arm 23, maintaining the said 25 arm in raised position and thus closing the circuit across the contacts I5a and IE1).

It will be apparent, that, due to the action of the float 25, the finger 26, carried by the arm 24, will be pressed against the arm 23 until the with- 80 drawal of liquid from the tank causes the float 25, carrying the shaft 24 and the finger 26, to fall, thereby permitting the arm 23 to fall and opening the circuit' across the contacts I511 and I517. 35

The contact I5a is connected to the frame I4, which is, in turn, in contact with the wire II through the contact switch I5. The contact I5!) is connected by the wire 28 with one end of the coil 29, the other end of which is connected ton-0 source of power I2 through the wire III. The valve 4 is mounted upon one end of a core or stem 30, the other end of which is positioned within the coil 29, and when a circuit is passed through said coil, core 30 and the valve 4 are 45 drawn downwardly against the action of spring 5, thereby opening the outlet 3 and permitting water collecting in the bottom of the tank I to be drawn off. As soon as the electrical circuit is broken, the valve 4 is restored by the spring 5 50 to close the exhaust passage 3.

When the water level in the tank rises so that the Water is in contact with the electrodes 9a and 9b, the circuit is closed, permitting current to flow from the source of power I2 through the wire ID to coil 29, wire 28, contact I51) and through the water to electrode 9a and the wire Ill back to the source of power l2. If, however, the liquid in the tank I is lowered below a predetermined point, the float 25 and sleeve 24 will move downwardly, thereby withdrawing finger 26 from the support of the arm 23 and breaking the circuit across the contacts 15a and I5b, thereby removing all danger of sparking of the electrodes, regardless of the presence of water in the bottom of the tank.

In order to test whether the device is functioning properly, separate hand operated means may be provided for closing the circuit, actuating the core stem 30, thereby opening the valve 4.

The making and breaking of the contact both indicate the liquid level, and both canv be made to operate a signal by well understood means, thus giving notice of the level of the liquid in the tank.

What I claim is:

1. Inv combination with a liquid storage tank having an outlet and a valve controlling said outletQelectrically operated means for opening said valve, a shaft extending into said tank, a pair of spaced electrodes carried by said shaft and connections between said electrodes and said electrically operated means, a switch intermediate said means and said electrodes, a float in said tank, control means for said switch, and means interconnecting said float and said control means.

2. In combination with a liquid storage tank having an outlet and a valve controlling said outlet, electrically operated means for opening said valve, a shaft extending into said tank, a pair of spaced electrodes carried by said shaft, extension members adjustably secured to said shaft, and extending below said electrodes, connections between said electrodes and said electrically operated means, a switch intermediate said means and said electrodes having a pivoted contact arm, a float in said tank, and support means for said arm controlled by the position of said float in said tank.

3. In combination with a liquid storage tank having an outlet and a valve controlling said outlet, electrically operated means for opening said valve, a pair of spaced electrodes in said tank, connections between said electrodes and said electrically operated means, a switch inter-'- rnediate said means and. said electrodes, afloat in said tank, and means interconnecting said float and said switch.

JAMES A. JONAS.