US1675058A - Electric control system for fuel-oil burners - Google Patents

Description

June 26, 1928. v 1,675,058

. L. L. SCOTT ELECTRIC CONTROL SYSTEM FOR FUEL OIL BURNERS Y Original Filed Aug. 12,1922

Fm. Z.

i1 v a;

ATTORNEY Patented June 26, 1928.

UNITED STATES 1,675,058 PATENT OFFICE.

LEWIS L. SCOTT, OF ST. LOUIS, MISSOURI, ASSIGNOR TO ELECTROL, INC., OF MISSOURI, OF ST. LOUIS, MISSOURI, A CORPORATION OF MISSOURI.

ELECTRIC CONTROL SYSTEM FOR FUEL-OIL IBURNERS.

Application filed August 12, 1922, Serial No. 581,540. Renewed April 6,1928.

This invention relates to novel automatic control apparatus particularly. suited for use with domestic oil burners.

One of the objects of my invention is to provide a simple control switch for controling the operation of the electric motor and ignition device used in oil burning heating system described in my application No. 465,- 835, filed April 30, 1921. Another object of my invention is to so arrange the control circuits to the ignition device and motor, that said motor switch will not be turned on unless the ignition switch is closed.

The invention is illustrated in the accompanying drawings, in which:

Figure 1 is a front view of my electric control system, showing a diagram of the wiring to the different parts of the system.

Figure 2 is a top view of the control switch shown in Figure 1.

Figure 3 is side view of the top part of the control switch shown-in Figure 1.

Referringnow to the drawings, the nu meral 1 indicates a board of insulating material on which are mounted the electromagnets A and -B in opposed relation. Pivotally mounted at .2 is an armature 3 which extends upwardly above the magnets. The socket 4 is formed at the upper end of armature 3, in which socket is mounted a ball 5 supported on a plunger .6 normally pressed upward'by spring 7. Pivotally mounted at one end 8, above the magnet B, is a contact member 9 having on its under side a contact 10, which normally rests upon the upper end of a set screw 11 forminga part of contact 12. The contact member 9 could assume this position by gravity but for the purpose-of rapidity and security in operation, I provide a spring 13 for securing such movement of the contact member from the upperposition. On the upper side of contact member 9 I provide also a contact I 14 which is adapted to be moved into engagement with the end of the screw 15 forming a part of a contact 16. Pivotally mounted at 17, above the magnet A, is a contact member 18 which is provided onits under side with a contact 19 adapted to rest upon the end of screw 20 forming a part of contact 21. The screw 22 forms a stop for the member 18 and the screw 23 forms a stop for the member 9. Between the free ends of the two contact members 9 and 18, and projecting outwardly a short distance from the switchboard 1 is a bar 24, the lower edge of which is rounded and located in the path of movement of the upper portion of the ball 5. This bar 24 co-operates with the armature 3 and ball 5 to insure a ,rapid upward movement of the respective the spring 4 instantly forces the said ball,

upward into engagement with the contact member 9 to raise same. The same operation occurs when the armature is moved toward the right with respect to contact member 18. p

' The numeral 25 indicates an electric motor which operates the air blower wheel 26 and the fuel pump 27; the suction pipe 28 runs to a fuel tank (not shown) and the discharge pipe 29 runs to the spray nozzle 30. Thefuel spray is mixed with .air from the blower wheel 26 and said fuel is ignited by the spark plug 31. The numeral 32 indicates a transformer for reducing the main line voltage to 15 volts for use with the spark coil'33 which coil furnishes the current for the spark plug 31. As it is only necessary for the plug 31 to spark for a. short period at the time the fuel spray starts, 1 provide the thermostatic switch 34 for breaking the circuit to spark coil 33, the operation of this thermostatic switch will be described later. 35 is a room thermostat. The battery 36 (or transformer if desired) is connected to wire 37 which wire runs to magnets A and B, and to thermostat 35. The main line wires are indicated by numeral-s 38 and 39; The wire 38 runs through contacts 11 and 12, and through the coil 40 on the thermostatic strip 34 and to the motor 25. It will be noted that when the armature 3 is in the position shown in Figure 1 the circuit to motor 25 is closed through contacts 10 and 11. The wire 39 runs to the motor 25 and also to transformer 32.. The wire 38 runs to transformer 32. The low voltage side of transformer 32 is connected to spark coil 33 through wire 41 position shown in Figure 1.

and through wire 42; the wire 42 runs through the switch 34 and then to coil 33 through wire 43. The wire 44 connects to the coil on magnet B and runs to contact 14 through contact 16 to contact 45 of the room thermostat. The wire 46 connects magnet A to contact 21 and runs through contact 19 then through wire 47, through contact 34 and through wire 48 to contact 49 of the room thermostat. It will be noted that the circuit to magnet A cannot be closed unless the contact 34 is closed; this is to prevent the turning on of the motor 25 unless the switch 'to spark coil 33 is closed.

The operation will now be described. Assuming that the room temperature drops below the point at which the thermostat is set, current will be sent to magnet A through the wires and contacts before described and magnet A will move armature 3 to the This operation closes the circuit to motor 25 (whereupon the fuel and air pumps are started) and also closes the circuit to transformer 32 which sends current to coil 33 and plug 31, the spark from the plug 31- ignites the fuel spray from the nozzle 30. The coil which is wound around the thermostatic strip 34 and which is connected in series with the motor 25 will heat the thermostatic strip 34 and within a minutes time the thermostatic stripwill move upward and break the circuit to the spark coil 33. The thermostatic strip 34 will remain in this raised position as long as the motor 25 is in operation. hen the room temperature reaches the point'at which the room thermostat is set, said thermostat will close the circuit to magnet B through contacts and wires before described and the armature 3 will move to the left and break the circuit to motor 25 and transformer 32 and will also break the circuit to magnet 13. As soon as the circuit to motor 25 is broken the thermostatic strip 34 will more downward until it rests on the screw 50. Should the contact 49 be manually closed before the thermostatic strip 34 reaches the screw 50 the magnet A will not be energized until the thermostatic strip 34 rests on the screw 50 so that the motor 25 will not start unless the spark control switch 34 is closed on contact '50.

I claim:

1. In an oil burning heating system, electrically-operated means for projecting air and sprayed liquid fuel into a zone of ignition, electrical means for igniting the fuel, a high voltage circuit including the fuel projecting means, a double magnet switch, the magnets whereof are included in a-low voltage circuit, a second low voltage circuit connected with said ignition means, means for starting and stopping the flow of electrical current to the ignition means, independent means for breaking the circuit to the ignition means, an armature adapted to be moved in opposite directions by energizing the respective magnets of said magnet switch, said switch having a plurality of means, including said starting and stopping means, controlled by the movement of said armature in one direction to close the circuit to the fuel projecting means, to start the flow of current to the ignition means, and to energize said independent means for breaking the circuit to the ignition means, and by its movement in the opposite direction, to open the circuit to said fuel projecting means and to break the low voltage circuit connected to said ignition means, and a room thermostat connected to one wire of said first named low voltage circuit and having a movable member for closing the circuit to one or the other of said magnets according to the rise or fall of temperature in the room above or below a predetermined degree.

2. In an oil burner control system, means including an electric motor for projecting fuel into a zone of ignition, means for lighting said fuel, an automatic switch for controlling the operation of the electric motor, a piece of thermostatic metal adapted to control the action of said automatic switch, an electric coil for heating said piece of in series with the electric motor.

In testimony whereof I have hereunto set thermostatic metal, said coil being connected

Images