DE1957920A1 - Device for triggering the start-up of a burner and the ignition of the fuel, which simultaneously performs a series of automatic controls - Google Patents

Description

Applicant: D. Olivetti & C. SpA Aprilia, Italy

Device for triggering the start-up of a burner igniting the fuel, which is one at the same time Series of automatic controls.

The present invention relates to a device which triggers the start-up of a burner and ignites the fuel (for example for heating systems or other uses), as well as a number of automatic controls, such as. B. the monitoring of the ignition within a predetermined safety period, the fire in the case the absence of the flame, as well as the switching off of the burner by the control effect of a separate thermostat. The establishment in question is as can be seen from the the following description shows, with self-locking

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ORIGINAL INSPECTED

■ - - 2 -

. see, in the sense that a disturbance in any of the various organs interrupts their functioning without that heating oil is lost, i.e. the means for interrupting operations take effect within a safety period.

Devices are already known which work with electromagnetic relays and thermal timing elements. The present A r ichtung however, does not use electromagnetic relays, but semiconductors. The absence of any normal working contacts ensures that the device has a high level of security during continuous operation, so that the need for maintenance is also reduced. The only remaining contact is that of the main switch, which due to its intended use is only activated in special cases and is therefore not prone to failure or is exposed to minor damage.

The device according to the invention is connected to an oil burner and can, if necessary, by closing the contact a thermostat to start the burner and ignite the fuel, with an electric motor for the supply this burner is provided. The engine in question causes the inflow of the atomized oil and the combustion air.

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In addition, a Traneformer is provided, which by means of an electrical discharge ignites the fuel flow generated by the burner.

The device according to the invention is characterized by that two switches made of semiconductors are provided, each of which is the transformer in question and the motor control, wherein an element is provided by means of which the closure of the switch is effected, which the Functioning of the transformer in question allows, and an arrangement with a resistor for a thermal Organ which acts on a main contact, the opening of which separates the device from the Hetz, the Hetz voltage present at the terminals of the transformer in question causes a current to flow through the resistance of the thermal element in question, while a second element is provided with which, when current flows through the resistance of the thermal element in question, the Closing of the switch is effected, which triggers the infeed, i.e. the running of the motor, whereby «! further a photoelectric organ is provided, which if his Resistance under the action of the light coming from the flame below a certain limit through which the current supplied by the element in question will flow through it,

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so that the closing of the switch for feeding the transformer "is effected, so that the current flow in the photoelectric element triggers the opening of the switch dee transformer, so that the spark is extinguished and In addition, the flow of current in this resistance of the thermal element is interrupted, this second element for Closing the switch of the motor has means which are actuated by closing the motor switch and, if the current flow stops in the resistance of the thermal element, the closing of the motor switch can be maintained, so that the duration of the flame is guaranteed, whereby the resistance of the thermal element is still suitable, case * if the ignition does not take place within the specified time, the main contact is switched off and thus the device rom Network.

To better illustrate these and other features of the device according to the invention, examples of the same are described in more detail below, with reference on the accompanying drawings in which to represent!

FIG. 1 shows an overall circuit diagram of the device!

FIG. 2 shows a special embodiment example of the device;

FIG. 3 shows a training modification compared to the figure

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T957920

In the drawings, 4 denotes the drive motor for the burner, which feeds in the fuel oil and the combustion air which it atomizes. With a transformer 3 is referred to, which brings the flow of fuel to ignition by triggering an electrical spark. 2 with a thermostat is referred to, which opens or closes a contact depending on the set temperature. With 1 a photoelectric element is indicated, i.e. an accessory, the resistance of which changes its value considerably when it is illuminated. The transformer 3 and the Motor 4- are each controlled by two switches 5 and 6, which mainly consist of semiconductors type thyristors. 7 with an element is referred to, which, as discussed later, is used to trigger the closure of the switch 5 and with 10 denotes a second element which, as will also be described in more detail later, causes the switch 6 to close. With 8 is the resistance of a thermal element denotes which, under certain conditions, as described in more detail later, causes a main contact 9 to open. 11 with a control member is referred to, which will also be described in more detail later.

Assuming that the contact 9 and the contact of the thermostat 2 are in the closed position, it flows Current through the element 7 · After initially the flame is still

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not "burns, the photo element 1 is still unlit and therefore shows a considerable resistance at its end contacts; in this case the current flowing in the element 7 causes the switch 5 to close (by means of a special current). If, on the other hand, the element 1 were illuminated it would have a low resistance at its end contacts, so that the power delivered to the element 7 harmonic currents, the element 1 has to flow and thus would not Ψ closing of the switch 5 occur. the question photoelectric element 1 can be optionally reinforced, without thereby the work described above would be significantly impaired.

Referring again to the closure of switch 5 (with unlit element 1) it is obvious that the transformer 3 is supplied so that the point is triggered. In addition, the mains voltage at the end contacts of the transformer 3 causes a current to flow through the resistor

stood 8 of the thermal element in question β and actuation of switch 6 via element 10 (which, like element 7, will be described in detail later). This runs the Motor 4- on so that the burner delivers atomized fuel, which is ignited by the spark released in transformer 3. This ignition must take place within a specified time, for example less than 10 seconds

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the one called the safety margin. If there is no ignition within this period , the current flowing through the resistor 8 in the meantime causes the thermal element in question to open the main contact 9 »so that the control device" locks ", ie disconnection from the mains .

Assuming that the ignition has taken place so that the photoelectric element 1 is illuminated, the current coming from the element 7 then flows through the element 1 and the switch 5 therefore does not remain closed. This extinguishes the spark (after the transformer 3 has remained de-energized) and, in addition, the flow of current through the thermal element 8 is interrupted. The element 10 causes the switch 6 to close when a voltage is present at its terminals 12 and IJ , ie when current is applied to the terminals 14 and 15. The voltage at terminals 12 and 13 therefore causes the switch 6, which is "latching" to close, after it itself causes the voltage at terminals 14 and 15. The device, with regard to the functioning or malfunction of certain parts, has the following characteristics:

- normal ignition condition. Within a safety period, controlled by an external thermostat.

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automatic re-ignition, if the flame fails, within a safety period. In this regard, it should be noted that the switch 5 is opened when the flame goes out at a certain moment; after element 1 is no longer illuminated, the current flows through element 7 and closes switch 5 »βο that the transformer is actuated and the flame is re-lit by means of its spark.

Failure of operation with illuminated element 1, at the moment of closing the contact of thermostat 2. It is possible determine that when this contact closes after element 1 is illuminated, the current through element 1 flows and therefore the switch 5 does not close, so that the burner does not work.

Does not work in the event that the photo element does not sense the flame or its connection to the power circuit fails. It is noted that the condition of this element comes in the same short-circuit the case above, the non-working, in the absence of illumination of the element 1 and therefore, the control behavior as in the previous case.

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- Intervention of the locking device if the photo element 1 or whose connections are switched off. It can be seen that if the photographic element 1 is open, it is the opening of the switch 5 can not trigger when the Flame is lit and it is illuminated, and therefore current continues to flow through the resistor 8 and the Contact 9 opens.

- Intervention of the locking device in the event of failure of the transformer 3 or the motor 4-, if the transformer fails, the flame is not lit and therefore the element 1 is not illuminated, so that the switch 5 also remains closed. This keeps flowing Current through resistor 8 and Eontakt 9 opens. If, on the other hand, the motor 4 does not work, the same occurs after the element 1 does not work in the absence of the flame is illuminated and therefore the switch 5 remains closed, so that current continues to flow through the resistor 8 and thereby the contact 9-

The device is complete in terms of self-monitoring protected. Every single component can be short-circuited or interrupted without being dangerous Circumstances can occur. The consequences are either

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the intervention of the locking device or failure. The only exception is the resistor 8 of the thermal element, it is assumed here that the interruption is the only type of shutdown. The circuit element 11 provides during the work breaks of the burner (contact 2 open) to ensure that there is no specific current flow, for example off a short circuit of the switch 5 and the switch 6; possibly it comes when the main switch 9 is applied ^ to the effect.

For the sake of greater completeness and also by way of example (and therefore not restrictive), two exemplary embodiments of the basic circuit are described below, and possible values of the circuit components are also given. The scheme according to FIG. 2 should be considered. In this case the components 7 and 10 are opto-electronic devices, which mainly consist of lamps and photoresistors. Closing the contact 2 causes the supply of the lamp L ,, which _{lowers the resistance of the photo resistor FE 2} and enables the tyrister 5 to close (via the circuit components O ₁ , G ^ and D ,, the latter is a bidirectional -Tyrister Diode), provided that the control photoresistor for the flame is not illuminated. The purpose of the optical-electrical component FH ₂ - L * is not to allow the switch 5 to close when the authorization 2 is open. This could be done by arranging 11

- 11 -

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- li -

Can be effected in parallel to the approval. You diodes ^D l ' ^D 2 ^{veitlin <ie: ri1 the} lighting of the lamp L, with the opening 2. The operation of 11 will be described in more detail later. In any case, the components D ,, ET, Dg »L *», as will be explained in more detail later, can be omitted in a simplified design of the control system. When the switch 5 is closed, the transformer 3 begins to trigger sparks or its electrical discharge. At the same time, an electric current flows into the thermal element 8, which lights the lamp L-, which is connected in series. This lamp L- illuminates the photo-resistor FR, which, connected in series with R-, causes the lyristor 6 to close, as a result of which the motor 4 is fed. The lamp Lp, which in turn _{illuminates the photo resistor FR 1} , is connected in parallel with the motor 4; as a result, the moment the lamp L is extinguished, the thyristor 6 is self-retaining. Once the fuel has ignited, the photo resistor opens the switch consisting of the thyristor 5; the current in the resistor 8 thus ceases. If the current is not switched off within the specified time, the heating of the resistor 8 causes the opening of the main contact 9 (which is kept open by the action of a mechanical self-holding device, which requires resetting by hand).

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Opening the thermostat 2 switches off the engine 4- . Working under other conditions is clear. Extinguishing the flame with the thermostat 2 closed: the photo resistor 1, which is no longer exposed to lighting, allows the switch 5 to be closed, which triggers the electrical discharge; If the re-ignition does not occur within the safety period, the thermal element 8 is used, which opens the contact 9. lighting

^ of the photo resistor at the moment of closing of 2: the photo resistor 1 does not allow the closing of the contact 5 when illuminated. As a result, the lamp L ₁ does not light up and the thyristor 6 is not closed. As far as self- control is concerned, a detailed explanation of the effects of groups 7 and 11 is given below. The case of the thyristor should be short-circuited 6, in certain cases it could be dangerous that no burning fuel is jetted, for example, when the photo-illuminated Wideretand 1 was at the moment of closure dee 2

ψ (light in the boiler) the motor is operated independently of the action of element 10. For this purpose the resistor RT is provided which, like 8, heats the thermal element that controls the contact 9. If the thyristor should be short-circuited 6, in open authorization 2, a current in ST would actuate the thermal contact. 9 Obviously, the current in RT is noticeably lower than that used by motor 4.

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However, in this state, the thyristor 5 would be supplied via RT. In order to remedy this shortcoming, the opto-electronic Device 7 is provided, which prevents the switch 5 from being supplied when 2 is open. The diodes D-, and Dp, which are opposite when 2 is open, prevent the ignition of the lamp L- in this state. The table summarizes the different states that can arise and the behavior of the corresponding devices. the Groups 11 and 7 provide a self-check for unlikely conditions (switch 6 short-circuited and lighting of the photo resistor 1 at the moment of closing 2) and in certain cases can be omitted: D ^, RT, D ^, L ,, FR "(C-, would be coupled directly to the anode of 5) .

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- 14 TABLE

Short circuit open

1. does not work is blocked

2. It's about that
Control body

3. It is always blocked, so it does not work 4-, there is always a blocking

5. No work is blocked

6. Blocking occurs. Blocking occurs

7. Any incident that causes 5 "not to be closed, leads to night work. Every process which the permanent closure caused by 5 triggers the blocking.

8. no working

9. The contact of the thermal element is only damaged by the absence of the contact.
10. Makes sense only for going into lockdown

FH Is
goes into lockdown

The description of the circuit according to FIG. 3 now follows. In this case, the component 10 has a transformer T ₁ and a directional diode D 1 (or a bridge), a capacitor C. The control of the transistor 6 is thus carried out by direct current . The current flow through the resistor 8 and

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the primary 12-13 of T ₁ triggers a voltage on the secondary , which is corrected and the thyristor 6 closes. The presence of the voltage at the end terminals of the motor becomes self-sustaining for the switch 6, which remains fed. In the following, the operation of the circuit is similar to that described with reference to the circuit shown in FIG . A malfunction of any kind on component 10 inevitably leads either to non-work or to blocking. The following information is given by way of example and not in a restrictive manner: C ₁ 0.047 _{/ U} F; C ₂ 0.047 / UF; C ₅ 100 / U? J H ₃ IK ohms; R ₅ 500 ohms; R ₁₅₀₀ 0hm; (8) 1.5 K ohms; D1-D2-M -1 N 1697; D _5-1 N 54-11; (5) TR ₁ - SC 40 D General Electric; (6) TR ₂ »SC 40 D General Electric; FR ₁ and FH ₂ - RPT 20 Philips.

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Claims (6)

Claims 1. Device in connection with an oil burner, which · on The response to the closing of a contact of a thermostat causes the burner to start up and the fuel to be ignited, the burner by means of an electric motor is voroorgt, which the feeding of the atomized oil and the combustion air, wherein a transformer (J) is provided, which by means of an electrical discharge ignites the fuel jet, characterized in that ) two switches (5, 6) consisting of semiconductors are provided, which respectively permit the operation of the transformer (3) and the motor (4) in question, with one element (7) is provided, via which the closing of the switch (5) which causes the transformer (3) in question to operate and an arrangement is provided which consists of a resistor (8) of a thermal element that can actuate a main contact (9), the opening of which disconnects the device from the network, the existence of the voltage of the network at the end terminals of the transformer (3) in question being suitable for a current flow through the resistance (8) of the thermal element in question, and a second element (10) is also provided, by means of which, when current flows through the thermal element in question Resistance (8) of the thermal element flitest, the SeSilieesen the switch (6) is effected, which the operation of the 009825/1324 Motor (4-) allows, whereby a photo-electric element (1) is also provided, which, when its resistance is under the influence of lighting, falls below a certain limit, through which the current supplied by the element in question (?) Flows that closes the switch (5), which in turn operates the transformer (3) in question, so that the flow of current in this photo element (1) triggers the opening of the switch (5) of this transformer (3), so d & es the dip is canceled and the current flow in this resistor (8) of the thermal element is also interrupted, the element (10) in question being suitable for closing the switch (6) of the motor (4), means (L ^, PR ^, T ₁ , D ^, C,) are provided, which are operated by the Schliesson the switch (6) of the motor (4) and when the current ^ flow in the resistor (8) of the thermal element stops, the closing of the Switch of the motor (4) can maintain, · Ο that the flame burns continuously, whereby the resistor (8) of the thermal element is suitable, if the ignition does not take place within the specified time, to trigger the opening of the main contact (9) and to disconnect the unit from the mains. 009825/1324 2. Device according to claim 1, characterized in that the switches (5, 6) in question, which are assigned to the transformer (3) and motor (4-) in question, consist of thyristors 3. Device according to claim I _1, characterized in that a unit (11) is provided parallel to the contact in question of the thermostat (2), by means of which, if the contact of the thermostat (2) is open during the break in work of the burner, a current flow arises, for example due to a short circuit of the switch (5) of the transformer (3) and the switch (6) of the motor, the opening of the main contact (9) is triggered. 4. The device according to claim 2, characterized in that the element in question (7) by means of which the closure of the switch (5) is effected, allows the operation of the transformer (3) in question, consists of a lamp (L 1) and one Photo resistor (FR ₂ ) which is illuminated by the lamp (L,) in question, so that the current flow in this lamp (L.) causes the resistance of the photo resistor (TRp) in question to be reduced and the switch in question (5) to close of the transformer lullest, by means of further circuit parts (O ₁ , Og , D ·). 001825/1324 5. The device according to claim 4, characterized in that the element in question (1O) ₁ by means of which the closure of the switch (6) is triggered , the operation of the motor (4 ·) allows, a lamp (L ₁ ), which in Is connected in series with the resistor (8) of the thermal element in question and a photo resistor (PR,) which is connected in series with a resistor (RO, this photo resistor, when it is powered by the lamp in question (L ,) is illuminated , the closing of the switch (6) of the motor triggers, whereby a second lamp (L2) is provided connected in parallel with the motor, which is also suitable to illuminate the photoresistor (PR,) in question, see above that when the first lamp (L ^) is switched off , the switch (6) of the motor in question is in the closed position. 009825/1324 6. Device according to claim 4, characterized in that that the element in question (10) by means of which the closure of the switch (6) is triggered, the operation of the Motor (4) has a transformer (T,) whose primary contact is in series with the resistor in question (8) of the thermal element, and that in cooperation with an alignment diode (D ^) or a bridge and a capacitor (C,) triggers the closure of the switch (6) of the motor in question, and also a circuit is provided, connected in parallel with the motor (4) and which is suitable for self-holding the switch (6) in question design in such a way that the power supply of the motor (4) is secured when the Stroafluss in the primary circuit of the question Transformer (T) stops. 008825/1324 Blank page