GB2102556A - Burner device - Google Patents

Abstract

A burner device for burning a low-volatility liquid fuel such as kerosine, comprising a main burner 40, an auxiliary burner 30 for preheating the main burner, a spark ignition device 20, a heat sensor 50, a fuel supply system and an actuating mechanism 10 provided with a restriction device, the actuating mechanism being operable in association with the heat sensor and the restriction device to activate the spark ignition device and the fuel system, so that the auxiliary burner is first ignited by an electric spark to preheat the main burner, to which the fuel is then supplied and the main burner is ignited by a second electric spark. <IMAGE>

Description

SPECIFICATION Burner device Background of the invention Low volatility liquid fuel is widely used for heating purposes such as in stoves and ovens for home use.

However, conventional burner devices in such applications have a common problem in the start-up, or ignition. They usually require a live flame to ignite.

Burner devices with spark ignition systems are available but the problem remain unsolved because low-volatility liquid fuel is not ignited easily by an electric spark without first being converted into a gaseous state.

In view of the aforesaid problem with conventional burner devices, the present invention offers a novel burner device having a main burner, an auxiliary burner for preheating the main burner, a fuel system supplying fuel to both burners, the fuel supplied to the auxiliary burner being mixed with pressurized air supplied from a source so that the auxiliary burner can be ignited easily by an electric spark, the fuel supplied to the main burner being then preheated to vaporize without mixing with pressurized air so that the main burner can also be ignited easily by an electric spark.The burner device of this invention is provided with a heat sensor, a restricting device, and an actuating mechanism operable with the heat sensor and the restricting device to assure that fuel is supplied to the main burner only after the main burner is properly preheated and before the electric spark is produced so that the main burner is ignited without failure.

Therefore, its is the main object of this invention to provide a novel burner device for low-volatility liquid fuel wherein the burner device can be ignited easily by an electric spark.

It is another object of this invention to provide a novel burner device for low-volatility liquid fuel having a main burner and an auxiliary burner, wherein the main burner is preheated by the auxiliary burner before the main burner is ignited to assure the burner device starts without failure.

Brief description of the drawings Figure 1 is a schematic drawing of an embodiment of the burner device according to this invention, showing the principles and the arrangement.

Figue 2 is a cross sectional view of a sleeve employed in the embodiment shown in Figure 1.

Figure 3 is a side view of the sleeve shown in Figure 2.

Figure 4, is a schematic drawing of the embodiment shown in Figure 1, showing the state in which the auxiliary burner is being ignited the fuel tank being omitted from the drawing.

Figure 5is a schematic, fragmentary drawing of the embodiment shown in Figure 1, showing the state in which the sleeve is rotated to allow the second push rod to move in the cylinder thus pulling up the cover of auxiliary burner for air to be drawn into the burner tube of the auxiliary burner. The fuel tank is omitted from the drawing.

Figure 6 is a schematic drawing of the embodiment shown in Figure 1, showing the state in which the main burner is being ignited. The fuel tank is not shown.

Detailed description of the invention As shown in Figure 1,the burner device of this invention comprises an actuating mechanism 10, an electric spark device 20, an auxiliary burner 30, a main burner 40, a heat, sensor 50 and a fuel supply system.

Actuating mechanism 10 comprises a sleeve 11, a cylinder 12 in which sleeve 11 is slidably inserted, cylinder 12 being fixedly supported by a frame structure F, a slender actuator rod 13 slidably inserted in sleeve 11, sleeve 11 having one end extending out of cylinder 12 (hereafter as outer end) and the other end urged by a spring 14, said outer end of sleeve 11 being provided with a knob 19 fixedly mounted thereon. Sleeve 11 is provided with a keyway 11 F in which a key 18 fixedly mounted on actuator rod 13 is slidably received, so that sleeve 11 is capable of sliding axially over the actuator rod 13 and yet capable of causing actuator rod 13 to rotate with it.

Actuator rod 13 has an outer end extending out of cylinder 12 and an inner end operably connected to a valve rod 47 to be explained later.

Actuating mechanism 10 further comprises at the inner end of cylinder 12 a first push rod 16 and second push rod 17 slidablysupported by frame structure F. First push rod 16, urged by a spring 16S towards sleeve 11, has one end extending to cylinder 12 and the opposite end connected to an actuator lever 191. Second push rod 17, urged by a spring 17S towards sleeve 11, has one end extending into cylinder 12 and the opposite end connected to an extension 61 which is further connected to a bellcrank 62.

Actuator lever 191 is pivotally mounted to frame structure F at pivot point 192, having a lower end provided with a lower extension plate 194 adapted to operate two valves 101 and 102, a mid portion pivotally connected to a restricting device or a dashpot 193, and an upper end provided with an upper extension plate 195 adapted to operate a first switch 201 and a second switch 202 to be described later.

Sleeve 11, as shown in Figures 2 and 3, is provided with sleeve body 11 E having a larger diameter and an outer extension 11 D having a smaller diameter, a cutout 1 1A at the inner end of sleeve 11, a central bore 11K having keyway 11F, an edge 11C and a step 11 H between sleeve body 11 E and outer extension 11 D, and a slot 11 B on the peripheral surface of sleeve body 11E,said slot 11B having an open end flush with edge 11C. Cutout 1 1A and slot 11B are so arranged apart from each other at a suitable angle, perhaps 90 degrees, that when cutout 1 1A is on the lefthand side when viewed from the inner end, slot 11 B is at the lower position.

Referring back to Figure 1, electric ignition device 20 comprises a high tension device 203 having a pair of primary terminals L1 and L2 and a pair of secondary terminals H1 and H2. Said high tension device 203 is adapted to produce a high voltage oscillating output (i.e. pulse) across the pair of secondary terminals H, and H2 when a low voltage, e.g. 3 volts D.C., is applied across the pair of primary terminals L1 and L2. A battery B and a first switch 201 connected in series are connected across the pair of primary terminals L1 and L2. the switch 201 being normally closed and operable by upper extension plate 195 to become open.Electric ignition device 20 further comprises a second switch 202 having a movable contact terminal P1, a first fixed contact terminal P2 connected to a first spark device 35, and a second fixed contact terminal P2 connected to a second spark device 45. One of the secondary terminals, e.g., H1, is connected to the frame structure, or ground, while the other, H2, is connected to the mobable contact terminal P1 with a flexible cord W1, movable contact terminal P, being mounted on one end of upper extension plate 195 which is also adapted at its other end to operate first switch 201.

When first switch 201 is closed, i.e., when upper extension plate 195 is apart from switch 201, high tension device 203 is energized to produce high voltage oscillating output, or pulse, across secon daryterminals H1 and H2, said high voltage pulse is then selectively transmitted either to first spark device 35 to produce a continuous spark at a spark gap 35G by moving movable contact terminal P1 to come into contact with first fixed contact terminal P2, orto second spark device 45 to produce a continuous spark at a spark gap 45G by moving movable contact terminal P, to come into contact with second fixed contact terminal P3.

Auxiliary burner 30 is provided with a burner tube 31 having a row of air inlet holes 34 around the lower end thereof, a cover 32 slidably mounted over burned tube 31 and capable of covering and uncovering air inlet holes 34, a nozzle 33 mounted at the lower end of burner tube 31, nozzle 33 having two inlet ports respectively connected to an air supply tube ( and fuel supply tube , said nozzle 33 adapted to eject a mixture of air and fuel into burner tube 31. First spark device 35 is mounted to burner tube 31, having an electrode 35P so mounted as to form a spark gap 35G with another electrode 31 P at the upper end of burner tube 31.Cover 32 is operatively connected to bellcrank 62 which is connected to extension rod 61 as described above, so as to cover or close air inlet holes 34 when second push rod 17 is pushed to move away from cylinder 12 by sleeve 11, and to uncover or to open air inlet holes 34 when second push rod 17 is urged to move towards cylinder 12 by spring 17S.

Main burner 40 is provided with a fuel supply port connected to a fuel supply tube ((3, a circular first preheating charmber 42 formed around a central tube 43 having mushroom-shaped structure 49, a second preheating chamber 44 formed in betweeen mushroom-shaped structure 49 and casing 48, and a plurality of orifices 45. A bowl-shaped fin 46 is formed around casing 48 for diverting the flame to be formed around casing 48 and also for receiving the heat produced by auxiliary burner 30.

Main burner 40 is further provided with a nozzle 41 having a control valve 41A for allowing or shutting off the supply cf fuel from fuel supply tube ( to nozzle 41 through first preheating chamber 42, control valve 41A having a valve rod 47 operatively connected to actuator rod 13. Second spark device 45, having an electrode 45P to form a spark gap 45G with the edge of bowl-shaped fin 46, is provided in the vicinity of main burner 40.

Second fixed contact terminal P3 is provided with a contact plate elongated along the direction of movement of movable contact terminal P1 so as to prolong the period of contact with the movable contact terminal P1 while movable contact terminal P1 is moving therealong.

Heat sensor 50 consists of a bi-metal strip 51 having one end fixed to main burner 40 and the other end so arranged as to come into contact with one end of latch lever 52. An adjustable screw 55 may be provided on the free end of the bi-metal strip to form a proper contact relation. Latch lever 52 is pivotally mounted on a bracket formed on cylinder 12 with the other end operatively connected to a latch pin 53, which is urged by a spring 54 and extends radially into cylinder 12 through opening 12B. When the burner device is not in use or the main burner is cold, bi-metal strip 51 is generally straight, thus leaving a certain gap between the free end of bi-metal strip 51 and the free end of latch lever 52 so as to enable latch pin 53 to be pushed into the cylinder to latch sleeve 11 when sleeve 11 is moved inwards (as shown in Figure 4).When main burner 40 is hot, bi-metal strip 51 warps from the heat thus pushing down the free end of latch lever 52, so as to pull up latch pin 54 and thus release sleeve 11 from being latched.

The fuel supply system comprises a fuel tank 131, an auxiliary air supply valve 101, an auxiliary fuel supply valve 102, a main fuel supply valve 103 and a pressurized air supply source 121.

Fuel tank 131 is filled with low-valatility liquid fuel, e.g., kerosine or the like through afillertube 132.

Pressurized air is supplied from the source 121, perhaps a hand operated pump, through a check valve 1 12, tube 0 to fuel tank 131. Check valve 112 is adapted to keep the pressure in fuel tank 131 after the source of pressurized air is removed. The pressurized air is also supplied from source 121 to auxiliary air supply valve 101 through tube (2) and to auxiliary burner 30 through tube (g3. The fuel in fuel tank 131, being pressurized by the pressurized air admitted into the tank, is supplied to a main service valve A through tube,and then supplied to auxiliary fuel supply valve 102 through tube 0, and to main fuel supply valve 103 through tube (g) . Fuel is further supplied from auxiliary fuel supply valve 102 to nozzle 33 of auxiliary burner 30 through tube (g), and from main fuel supply valve 103 to main burner through tube respectively. A pressure relief valve, or safety valve 122 is provided to flee the air in the tank when pressure in the tank exceeds a certain level. In addition, a manually operated pressure relief valve 123 operable with a handle 124 is provided to enable a manual relief of pressure in the tank when so required.

Main fuel supply valve 103 is provided with a plunger 1 03V constantly urged by a spring 103S so as to close a passage 103P therein, the plunger being operable with a lever 104 which is pivotally mounted onto the frame structure, and has an upper end extending radially into cylinder 12 through an opening 12A. The upper end of lever 104 is adapted to slidably fit into slot 11 B of sleeve 11 when slot 11 B is aligned therewith. Lever 104 is so arranged with respect to sleeve 11 that when sleeve 11 is at the far right, or the outer position, with slot 11 B aligned with the upper end of lever 104, the upper end of lever 104 is engaged in slot 11 B thus preventing sleeve 11 from rotating as shown in Figure land main fuel supply valve 103 is closed.The main fuel supply valve 103 remains closed when sleeve 11 is moved inwards as shown in Figure 4, however, the upper end of lever 104 is disengaged from slot 11 B, or cleared from edge 11 C thus allowing sleeve 11 to rotate as shown in Figure 4, so that actuator rod 13 can rotate to open the control valve 41A in main burner 40 and in the meantime cutout 1 1A on sleeve 11 can be aligned with second push rod 17 to allow second push rod 17 to be pushed into cutout 11A, resulting in moving cover 32 of the auxiliary burner upwards to open air inlet holes 34 as shown in Figure 5.

Sleeve 11, having been moved inwards and rotated to open the control valve 41A in main burner 40, will be able to push the upper end of lever 104 with edge 1 1C as soon as latch pin 53 is pulled up and sleeve 11 is allowed to move outwards, so as to open main fuel supply valve 103.

This arrangement constitutes an interlock relation between main fuel supply valve 103, control valve 41A in main burner 40, cover 32 of auxiliary burner 30, auxiliary air supply valve 101 and auxiliary fuel supply valve 102 to be described later.

Auxiliary air supply valve 101 and auxiliary fuel supply valve 102 are respectively provided with plungers 101V, 102V constantly urged by spring 101S,102S, respectively, to close passages 101 P, 102Ptherein. Plungers 101V, 102V are operable by lower extension plate 194 provided at the lower end of actuating lever 191,so as to open valves 101, 102 when lower extension plate 194 is moved to push the plungers into the valves.

The function, operation and feature of the burner device of this invention will now be described.

In Figure 1, there is shown schematically the burner device of this invention not in use. Sleeve 11 is urged by spring 14 and is at the far right, or outer position, with slot 11 B aligned with the supper end of lever 104 so as to receive the upper end of lever 104 freely therein, thus allowing main fuel supply valve 103 to be closed. In the meantime latch pin 53 having its lower end abutting on the sleeve body 11 E is in raised position, and both first and second push rods 16 and 17 are urged by respective springs 16S and 17S to extend axially into cylinder 12 to abut on the inner end of sleeve 11.Actuating lever 191 is urged by spring 16S into a position where upper extension plate 195 abuts on first switch 201 to cause first switch 201 to open; in the meantime moveable contactterminal P1 is apart from both first and second fixed contact terminals P2 and Ps while lower extension plate 194 is apart from both plungers 101V and 102V of auxiliary air supply valve 101 and auxiliary fuel supply valve 102 so as to keep both valves closed. Furthermore, the control valve 41A for nozzle 41 of main burner 40 is closed while actuating rod 13 is in such position that slot 11 B is aligned to receive the upper end of lever 104 for operating main fuel supply valve 103.

In this condition sliding cover 32 of auxiliary burner 30 is raised to open the air inlet holes 94.

To use the burner device, first fuel tank 131 is filled with fuel, which is then pressurized by pressurized air from appropriate source 121. Check valve 112 acts to maintain the pressure in the tank even after the source for pressurized air is removed or stopped.

Next, with battery B for the ignition device 20 properly arranged, knob 19 is pushed to move sleeve 11 inwards as shown in Figure 4. Then the following events occur simultaneously in association with the inward movement of sleeve 11: second push rod 17 is pushed to move away from cylinder 12 thus causing cover 32 to move down to close air inlet holes 34 of auxiliary burner 30; first push rod 16 is pushed to move away from cylinder 12 thus causing actuating lever 191 to sway counterclockwise with respect to pivot point 192, resulting in moving upper extension plate 195 away from first switch 201 and lower extension plate 194 towards auxiliary air supply valve 101 and auxiliary fuel supply valve 102.

first switch 201 is closed and high tension device 203 is energized; moveable contact point P1 is brought into contact with first fixed contact terminal P2, causing a contineous spark to take place at spark gap 35P of spark device 35 for auxiliary burner 30; auxiliary air supply valve 101 and auxiliary fuel supply valve 102 are opened to allow a supply of pressurized air and fuel to nozzle 33, where the pressurized air and fuel are mixed while being ejected from nozzle 33 into burner tube 31 and ignited by the spark at the upper end of burner tube 31; dash pot rod 193A is pulled out; edge 11C clears latch pin 53, allowing latch pin 53 to be pushed radially into cylinder 12 to latch sleeve 11, thus preventing sleeve 11 from moving outwards; and the free end of latch lever 52 is moved up to come into contact with the free end of bi-metal strip 51.

Lever 104 is not associated with the above process and thus main fuel supply valve 103 remains closed.

It is to be noted that with sleeve 11 moved inwards and latched by latch pin 53, edge 11C of sleeve 11 clears the upper end of lever 104 to enable sleeve 11 to rotate.

Thirdly, actuating rod 13 is rotated counterclockwise (facing from right to left, or inwardly) by rotating knob 19 approximately 45 degrees, to move cutout 1 1A of sleeve 11 upwards to be aligned with first push rod 17 while moving slot 11 B out of alignment with lever 104. Then the inner end of first push rod 17 being urged by spring 17S, is a allowed to move into cutout 11A, as shown in Figure 5, resulting in sliding cover 32 upwardly to open air inlet holes 34, thus allowing sufficient air to be supplied through air inlet holes 34 into the burner tube 31 to further intensify the flame. In the meantime, the counterclockwise rotation of actuator rod 13 causes control valve 41A to open, thus allowing nozzle 41 of main burner to become operable.It is to be noted that as soon as sleeve 11 is rotated, slot 11 B is moved out of alignment with the upper end of lever 104, and thus the upper end of lever 104 comes into abutment with edge 11 C of sleeve 11, as shown in Figure 5.

As auxiliary burner 30 has been ignited to heat main burner 40, the heat main burner received is conducted to bi-metal strip 51, causing bi-metal strip 51 to warp, and consequently the free end of latch lever 52 is pushed down and latch pin 53 is pulled up to release sleeve 11 from being latched. Sleeve 11, being urged by spring 14, then moves outwardly, thus causing the following events to occur accordingly:: lever 104, having the upper end abutting on edge 1 1C of sleeve 11, is pushed by sleeve 11 to sway outwardly to open main fuel supply valve 103, thus allowing pressurized fuel to be supplied to main burner 40; second push rod 16, being urged by spring 16S, is allowed to move in cylinder 12, causing actuating lever 191 to sway clockwise with respect to pivot point 192, upper extension plate 195 to move toward first switch 201, lower extension plate 194 to move away from auxiliary air supply valve 101 and auxiliarty fuel supply valve 102; auxiliary air supply valve 102 and auxiliary fuel supply valve 102 are closed to shut off the supply of air and fuel to auxiliary burner 30.

moveable contact P1 is brought into contact with second fixed contact terminal P3 from first fixed contact terminal P2 to produce a continuous spark at spark gap 45G of spark device 45 for main burner 40 before the upper extension plate 195 reaches first switch 201; and dash pot rod 193A is pushed into dash pot 193 to restrict the speed of movement of actuating lever 191.

Since sleeve 11 is moved outwardly without restriction while actuating lever 191 is moved in the same direction with restriction by dash pot 193, actuating lever 191 moves slower than sleeve 11.

The slower movement of actuating lever 191 enables: main fuel supply valve 103 to be opened by lever 104 to allow the supply of fuel to main burner 40 before moveable contact terminal P1 is brought into contact with second fixed contact terminal P3 from first fixed contact terminal P2, to assure fuel reaches main burner 40 and is preheated in first preheating chamber 42, then ejected by nozzle 41 to draw air into central tube 43 to be mixed with the fuel, further preheated in second preheating chamber 44 and at last discharged through orifices 60 before the spark is produced; and the duration of continuous spark at spark gap 45G is prolonged by the slow movement of movable contact terminal P1 over second fixed contact terminal P3 having an elongated contact plate, to further assure main burner is ignited without failure.

At the end of the movement of actuating lever 191 upper extension plate 195 pushes first switch 201 to open and thus to turn off high tension device 203, and in the meantime, movable contact terminal P1 is moved apart from second fixed contact terminal P3 to extinguish the spark. Accordingly, main fuel supply valve 103 remains open to maintain the supply of fuel to main burner 40 while the supply of air and fuel to auxiliary burner 30 has been shut off.

To extinguish main burner 40, sleeve 11 is rotated clockwise to close the control valve 41A and in the meantime to move slot 11 B of sleeve into alignment with the upper end of lever 104, which, being urged by spring 103S in main fuel supply valve 103, is then allowed to move freely into slot 11 B, resulting in the closure of main fuel supply valve 103. The supply of fuel to main burner is cut off accordingly.

Accordingly, a preferred embodiment of the present invention has been described above. It is to be understood that the present invention may be embodied otherwise than as herein specifically illustrated or described, and the construction and arrangement of parts may be changed without departing from the principles and scope of this invention as defined in the appended claims.

Claims (7)

1. A burner device, comprising: (a) an auxiliary burner having a first nozzle and a first spark device; (b) a main burner having a second nozzle, a control valve for closing and opening a fuel passage to said second nozzle, said fuel passage being built in said main burner, and a second spark device, (c) an electric spark ignition device having a high tension device capable or producing an electric spark at said first or second spark device, a first switch adapted to energize or de-energize said high tension device and a second switch for selectively allowing said electric spark to be produced at said first spark device or second spark device; (d) a first valve for allowing or stopping a supply of liquid fuel to said main burner; (e) a second valve for allowing or stopping a supply of liquid fuel to said auxiliary burner;; (f) a third valve for allowing or stopping a supply of pressurized air to said auxiliary burner; (g) actuating menas capable of moving in one direction to operate said first switch, second switch, second valve and third valve so as: (i) to open said second and third valves to allow fuel and pressurized air to be supplied to said auxiliary burner while keeping said control valve and said first valve closed; (ii) to close said first switch to energize said high tension device, and (iii) to actuate said second switch to produce an electric spark at said first spark device to ignite said auxiliary burner.

2. The burner device as recited in claim 1, wherein said actuating means is further provided with: (a) urging means for urging said actuating means in an opposite direction; (b) latching means for latching said actuating means at the end of movement in said one direction; (c) releasing means for operating said latching means in response to heat conducted from said main furner to release said actuating means from being latched to allow said actuating means to move in the opposite direction, so as:: (i) to open said first valve to allow the fuel to be supplied to said main burner; (ii) to actuate said second switch to allow said electric spark to be produced at said second spark device of said main burner to ignite the main burner, (iii) to close said first and second valves to cut off the supply of fuel to said auxiliary burner; (d) a restricting means adapted to delay the operation of said second switch, said second and third valves with respect to said first valve when said actuating means is released by said releasing means to move in the opposite direction.

3. The burner device as recited in claim 2, wherein said releasing means comprises a bi-metal strip fixedly mounted to said main burner.

4. The burner device as recited in claim 2 wherein said actuating means comprises: a sleeve slidably mounted on a rod operatively connected to said control valve of said main burner; a first push rod operable with said sleeve in said one direction and urged in the opposite direction by a spring; and an actuating lever operatively connected to said first push rod, said actuating lever having one end adapted to operate said first switch and said second switch, and other end adapted to operate said second and third valves, and having said restricting means operatively connected thereto.

5. The burner devices as recited in claim 4, wherein said restricting means is a dashpot.

6. The burner device as recited in claim 2, wherein said actuting means is capable of moving in a third direction for opening said control valve in said main burner, in a fourth direction opposite to said third direction for closing said control valve in said main burner, and is provided with interlocking means adapted: (a) to prevent said actuating means from moving in said third and fourth directions when said first, second and third valves are closed; (b) to allow said actuating means to move in said third direction when said second and third valves are open; (c) to enable said first valve to open only after said actuating means is first moved in said one direction and then in said third direction to open said control valve in said main burner, and (d) to allow said actuating means to move in said fourth direction when said first valve is open.

7. The burner device as recited in claim 1, wherein said auxiliary burner further comprises: a burner tube having a row of air inlet holes, a coverslidably mounted over said burner tube and operable in association with said actuating means so as to cover said air inlet holes when said actuating means is moved in said one direction, and to uncover said air inlet holes when said actuating means is moved in the opposition or in third direction.