FR2555297A1 - ORDERING THE AIR COMPARTMENT OF A TWO-STAGE BURNER, WITH FIELD OR GAS - Google Patents

Abstract

CONTROL OF THE AIR SHUTTER OF A TWO-STAGE ATMOSPHERIC BURNER, USING A HEATING AUTOMATE WITHOUT MOTORIZED PROGRAMMER. A LACK OF VOLTAGE 19 ALREADY EXISTING IN THE AIR SHUTTER ACTUATOR, A SINGLE-WIRE CONTROL RELAY 24 AND THE SWITCHES 21, 26, 27, 28, 29 ACTUATED BY THE DRIVE MOTOR 22 OF A SHUTTER D 'AIR CONSTITUTE AN ASSEMBLY WHICH GUARANTEES THE FOLLOWING PROGRAMMED SEQUENCE: PREVENTILATION BEFORE EACH BURNER START-UP AND AFTER A FAILURE OF THE VOLTAGE IN SERVICE, THE AIR SHUTTER BEING AT LEAST PARTIALLY OPEN; POSITION OF THE AIR SHUTTER ALWAYS IDENTICAL, BOTH WHEN STARTING THE FIRST STAGE OF THE BURNER AND AFTER THE SECOND STAGE IS TURNED OFF.

Description

The present invention relates to a control of the air shutter of a burner

  atmospheric with a first and second stage of operation

  in oil or gas heating systems, with a

  heating mat without programmer; a motorized air shutter actuator which, before putting the atmospheric burner into operation, opens a

  air flap at least partially for pre-ventilation; com

  mutators which determine the position of the air shutter for a first stage of the burner and signal the heating automat to the minimum open position of the air shutter required for commissioning by short-circuiting a terminal input and output terminal; a delay element, mounted in the heating automaton and acting by a regulator of the second stage of the burner on a single-wire control relay which, under tension, controls by its reversing contact a direction of rotation of the drive motor and, without voltage, controls the other direction of rotation; and an undervoltage relay which, when the voltage is restored after a failure, passes

  the air shutter in its closed position.

  The rise of two-stage burners, even in the field of low heating power, requires smaller and less expensive heating automats, not including a motorized programmer

  and nevertheless delivering the necessary signals for the temporal sequence

  commissioning porch for the two stages of the burner. For the use

  tion of burners with one or two stages of spraying, there are such heating automats generally comprising a

  thermal delay and, subject to certain limitations, are

  sands also with air shutter actuators for such burners

  their two-stage oil or gas windwinds, and for which pre-ventilation is imperatively specified before each

  service. Two relays, known as single control relays

  wired and undervoltage relays are incor-

  pores to the air shutter actuator. In such an application, the

  air shutter must, for pre-purifi-

  low load, which is determined by a first cam-controlled auxiliary switch in the actuator. When the start-low load position is reached, the commissioning of the first stage of the burner is carried out by the start of a pre-purge and, when the thermal demand requires it, the commissioning of the second stage of the burner follows immediately, as soon as the air shutter has reached

its fully open position.

  The first stage of the burner remains in operation when the second stage is switched off, first with excess air, until the air damper has reached its low load operating position. The latter is reached in the operating direction opposite to that of the start, and determined by a second switch

  auxiliary controlled by cam. For technical reasons of

  the switching points of the two auxiliary switches

  determining the positions of low starting load and operating

  should not overlap, but should have a gauge that can not be reduced at will to ensure trouble-free operation. The switching interval therefore imposes for the two operating directions two low-load positions of the first stage of the burner, different from the

  position of the shutter. This solution is troublesome for technical reasons.

  combustion and the setting of the auxiliary switches

  neighboring switching points is difficult.

  The invention relates to an air shutter control which, although controlled only by a simple heating controller without a motorized programmer, always guarantees the same low position.

load of the air shutter.

  According to an essential characteristic, in addition to the switches short-circuiting the input and output terminals, means are

  provided for the further rotation of the engine

  during the short-circuiting by the switch, so that the position of the air shutter corresponding to the first stage of the burner is determined solely by an auxiliary switch of the drive motor, which acts in the closing direction of the

air shutter.

  Other features and advantages of the invention will be

  better understood using the detailed description below of

  three exemplary embodiments and the appended drawings in which:

  Figures 1 and 2 show the diagram and a diagram of a

known command;

  Figures 3 and 4 show the diagram and the corresponding diagram.

  a first embodiment of the invention; Figures 5 and 6 show the diagram and the corresponding diagram of a second embodiment of the invention; and

  Figures 7 and 8 show the diagram and the diagram of a third

  second embodiment of the invention.

  The same parts are designated by the same references on

all the figures.

  A known heating automat 1 (for example of the LOA type of the Applicant) is shown in FIGS. 1, 3, 5 and 7. It is used with air shutter actuators 2, 3, 4, 5 in all embodiments of the air shutter control described below, and its operation is first briefly described with the help of

  the known air shutter actuator 2.

  A phase wire L feeds the air shutter actuator 2 via a terminal 6, as well as the heating automat 1 via a regulator 7. When the safety contact 8 of a thermal trip device 9 is closed, the voltage of the phase wire L is also applied to an input terminal 10 and a terminal 11 of the air shutter actuator 2, 3, 4, 5. At each commissioning, the thermal trip unit 9 actuates a timer 12, which then connects an output terminal 13 on the one hand to a terminal 15, via

  another regulator 14, and on the other hand to a terminal 16.

  flante 17 is connected to the output terminal 13 and the terminal 16 is connected to a first fuel valve 18. A flame controller, part of the heating automat 1 and verifying the presence of a flame, is not represented. In the absence of

  flame, the thermal release 9 then opens the safety contact

  8 in a known manner. A relay with no voltage 19 comprises an inverter 20 whose resting contact, when the relay 19 is

  not energized, closes a circuit which, by means of an interrup-

  limit switch 21, operates the drive motor

  22 of an air shutter not shown in the closing direction, jus-

  that the limit switch 21 interrupts the circuit in the closed position of the air shutter. The drive motor 22 is connected directly to a neutral. The undervoltage relay 19 is connected to the input terminal 10 and has a second working contact 23. A single-wire control relay 24 is connected between the neutral N and the terminal 15, and actuates an inverter 25 which preselects the "closing" circuit of the drive motor 22, on its position

  of rest, and the circuit "opening" on its working position.

  In addition to limit switches 21 (closing) and 26 (opening), the drive motor actuates three auxiliary switches 27, 28, 29 via control cams

adjustable.

  Figures 2, 4, 6 and 8 show diagrams of functions

  the position of the air shutter, the position being

  on the ordinate and the time t on the abscissa. The shutter is closed in Z and opened fully at A. When commissioning the installation according to Figures 1 and 2, the regulator 7 closes and feeds the relay with no voltage 19. The working contact 23 of the latter operates the drive motor 22 in the opening direction, until

  its auxiliary inverter 28 disengages the drive motor.

  22 in the position of low starting load M of the air shutter, at point 30 (Figure 2), activates the timer 12 by the

  output terminal 13, and branches the fan 17 and a device

  ignition not shown. At the end of the pre-ventilation time

  determined by the timer 12, the contacts of the latter

  the fuel valve 18 then, after a certain time (interval), turn on the regulator 14. The flame controller detects the flame then produced, stops the trigger

  9 and maintains its timer 12 closed. This state

  responds to the first stage of the burner with the low position

  starting load of the air shutter.

  When the regulator 14 is closed, because it also requires heat, the single-wire control relay 24 is energized and the driving motor 22 receives, at point 31 of FIG.

  opening signal through 10, 11, 25, 23, 26.

  auxiliary switch 29 closes at the following point 32, first without action, then at point 33, the auxiliary switch 27 puts a second fuel valve 35 under tension via

  of a terminal 34. The second stage of the burner is thus reached.

  The limit switch 26 interrupts the drive motor at

point 36.

  When switching off the regulator 14 at point 37 of FIG. 2, the single-wire control relay 24 trips and its inverter 25

  operates the drive motor 22 in the direction of closing

  29, 20, 21. The auxiliary switch 27 interrupts the voltage of the second fuel valve 35 at point 38. The auxiliary switch 29 opens at point 39, and stops

  drive motor 22 to a low load position of operation

  air shutter, which has a value as high as

  low starting load, as previously indicated.

  The diagram in FIG. 2 also represents the break in

two floors.

  Before describing the exemplary embodiments of the invention according to FIGS. 3, 5 and 7, it is necessary to specify the details common to the three embodiments, using the references

  used for the description of the known arrangement (Figure 1).

  A rest contact 40 of the single-wire control relay 24 is inserted into the connection of the phase wire L, between the terminal 6 and the

  reset contact of the inverter 20 of the undervoltage relay 19.

  A connection is then established with the end switch of

  closing stroke 21 of the drive motor 22.

  The voltage of the phase wire L is further applied to the terminals

  and 11 by the first regulator 7 and the safety contact 8.

  A link is established between the terminal 11 and the inverter 25 of the single-wire control relay 24 and, in the rest position of the latter, the auxiliary switch 29, which is connected to the rest contact of the inverter 20. The working contact of the inverter 25

  is connected by a wire 45 to the opening limit switch

  26 of the drive motor 22. The latter is connected directly

  Neutral N, as well as relays 24 and 19.

  Another inverter 41 of the undervoltage relay 19 connects, in its rest position, the single-wire control relay 24 to the input terminal 10, while its working contact is connected to the terminal 15 and consequently to the regulator 14, so that it is powered up by the timer 12 of the heating controller 1 and

  the second regulator 14 only at the end of the interval time.

  The switch 26 (FIGS. 3, 4; 5, 6) or 28 (FIGS. 7, 8), determining the maximum opening of the air shutter during the pre-purge time, simultaneously feeds the undervoltage relay 19, whose connection 42 was previously voltage free. The connection 42 is further connected by a self-maintaining contact 43 to one of the

  terminals 10 and 13, as described later.

  As in the known arrangement according to FIG. 1, a connection is also established in FIGS. 3, 5 and 7 between the terminal 16,

  connected to the first fuel valve 18, the terminal 34

  via an auxiliary switch 27, and the second fuel valve 35. In the air shutter control according to FIGS. 3 and 7, the auxiliary switch 28 is connected between the input and output terminals 10 and 13 In the example according to FIG. 3, the limit switch 26 reacting to the full opening

  the air shutter is realized as an inverter. Invert contact

  26a of the limit switch 26, switched to the limit position "open", is connected to the connection 42 of the undervoltage relay 19. When the latter is powered, its contact

  latch 43 connects the connection 42 to the output terminal 13.

  In the embodiment according to FIG. 5, the contact of

  holding 43 bypasses the input and output terminals 10 and

  13 when the undervoltage relay 19 is energized, and the

  limit switch 26 reacting to the full opening of the

  Air shutter is also realized as an inverter. His

  inverter tact 26a is connected to the connection 42 and the terminal of

exit 13.

  In the embodiment according to FIG. 7, the auxiliary switch 28 connects, as previously indicated, the input and output terminals 10 and 13. Its control cam is adjusted in such a way that

2555 297

  that it reacts in point 47 of Figure 8, on a position of the air shutter intermediate between those corresponding to the first and the

  second stage of the burner. The connection 42 of the relay with no voltage

  sion 19 is further connected to the output terminal 13.

  The operation of the air shutter controls according to FIGS. 3, 5 and 7 is described below with reference to FIGS. 4, 6 and 8. In the three embodiments, the air shutter control is set energized at time tl, by closing the contacts of the regulator 7 for example. A single-wire control relay 24 is powered by L, 7, 8, 10, 41, 24, N and its inverter 25 establishes as follows an open circuit by the drive motor 22:

  L, 7, 8, 10, 11, 25, 45, 26, 22, N. The air shutter begins to open.

  In the air shutter control according to FIG. 3, the auxiliary switch

  liaire 28 bypasses the terminals 10 and 13 before the total opening of the air shutter, at time t2 (Figure 4) and at point 46, so

  that the timer 12 and the fan 17 are energized.

  The pre-ventilation starts, the duration of which is determined by the timer 12. According to the diagram of FIG. 4, the point 46 is located below the position M of the air shutter corresponding to the first stage of the burner. It could also be above. The

  air shutter continues to open, until its open position

  A is reached at point 47. The auxiliary switch

  29 closed during the opening race and at point 47 the

  limit switch 26 interrupts the drive motor 22 and, by its inverter 26a and the connection 42, supplies the relay with no voltage 19. As a result of the closing of its safety contact 43, the relay misses voltage 19 is now supplied by the input terminal 10 and the auxiliary contact 28.

  relay with no voltage 19 simultaneously activates its

  pourers 41 and 20, which triggers the single-wire control relay 24, since the terminal 15 is not yet energized. A circuit is established as follows between the input terminal 10 and the closing side of the drive motor 22: 10, 11, 25, 29, 20, 21, 22, N. The drive motor 22 therefore continues to operate but now in the closing direction, until the position of the

255529 7

  air flap corresponding to the first stage of the burner is reached by the auxiliary switch 29 acting only in the direction of closing, and that it closes the drive motor 22 at point 48. The air shutter is immobilized in its position M. The first fuel valve 18 is energized at the end of the pre-purge time set by the timer 12. A flame is produced and detected by the not shown flame controller which, by acting on the timer 12, interrupts the pursuit of

  heating of the thermal release 9 and, after cooling

  also puts the regulator 14 under tension. Commissioning

  the first stage of the burner is thus completed.

  Provided that the switch of the second regulator 14 is closed, the single-wire control relay 24 is powered by the terminal 15 and the inverter 41. Its inverter 25 establishes from the input terminal 10 a circuit 10, 11, 25, 45, 26, 22, N which makes of

  again operate the drive motor 22 in the direction of

  (point 49, figure 4), until the auxiliary switch

  27 reacts, closes a circuit between the timer 12 and the second fuel valve 35 through 16, 27,

  34, and thus releases the second stage of the burner (point 50, Figure 4).

  The drive motor 22 continues to operate until it reaches

  pure by the limit switch 26 in the position of o-

  maximum vertex A (point 51, figure 4). All the power of

burner is thus available.

  The single-wire control relay 24 triggers when the regulation

  14 opens. Circuit 10, 11, 25, 29, 20, 21, 22, N is restored

  from the input terminal 10 and operates the motor of

  22 in the closing direction, as was the case from point 47. The auxiliary switch 27 then opens and cuts the second fuel valve 35. The position of the air flap corresponding to the first stage of the burner is again reached in the closing direction; it is identical to that determined by the opening of the auxiliary switch 29 during commissioning

  (point 48). This phenomenon can be repeated several times,

  that the first stage of the burner is also cut off by a response from the regulator 7 (point 52). The relay with no voltage 19 then triggers, as well as the single-wire control relay 24, and the air shutter is closed by the circuit L, 6, 40, 20, 21, 22, N, until the limit switch 21 opens in the open position. Only differences in operation of the shutter control

  5 and that according to FIG. 3 are described below.

  below. During commissioning, and contrary to the case of the command according to Figure 3, the air shutter first opens completely

  until the limit switch 26 responds to the

  both t2, stops the drive motor 22 and simultaneously feeds the undervoltage relay 19 (point 47, Figure 6). The PM contact 43 bypasses the input and output terminals and 13, and starts the pre-purge at time t2. At the same time, the inverter 20 changes its position and the circuit 10, 11, 25, 29, 20, 21, 22, N starting from the input terminal 10 causes the shutter to move

  in the direction of closing, until the auxiliary switch

  29, actuated in the closing direction, switches off the motor

  22 at point 48. For the rest of the sequence, refer to

  to the comments relating to Figures 3 and 4.

  The assembly according to FIG. 5 which has just been described makes it possible to

  remove the auxiliary switch 28 (Figure 3) and its cam com

  mande. The air shutter opens fully every time it is put into service.

  This achievement is therefore better suited to short-term

  of the drive motor 22, such as those of the oil burners. The air shutter control according to FIGS. 7 and 8, on the other hand, is better for long operating times, such as those used with the gas, the air shutter not having to move.

  to its fully open position during commissioning.

  The auxiliary switch 28 reacts previously, and also bypasses the input terminals 10 and 13 at time t2, at point 47

  (Figure 8), which triggers pre-ventilation and simultaneously feeds

  The latter causes its inverter 20 to restart the drive motor 22 in the closing direction, until the auxiliary switch 29 again cuts the drive motor in the right direction. 48 (Figure 8), as previously described. The rest of the sequence is again

  the same as that described for Figures 3 and 5.

  All the examples of realization guarantee that each extinction

  of the flame or each voltage failure in operation

  result in a complete restart. The position of the air shutter

  when commissioning the first stage of the burner is rigorously

  the same as that obtained after a second stage on-off cycle, which should also be noted that it can also be continuously adjustable. The same position of the air shutter is always reached, although a simple heating controller without a motorized programmer is used, and without a difficult alternating balancing of the switching points of two switches actuated by the motor.

  drive 22 is necessary.

  Of course, various modifications can be made by those skilled in the art to the principle and to the devices which have just been described as non-limiting examples, without departing from the

framework of the invention.

Claims (6)

claims   1. Control of the air shutter of an atmospheric burner with a prener and a second stage of operation in heating installations with oil or gas, with a heating automat without programmer; a motorized air shutter actuator which, prior to putting the atmospheric burner into operation, opens an air gap at least partially for pre-ventilation; switches that determine the position   of the air shutter for a first stage of the burner and signal to the   heats up the minimum open position of the air shutter required for commissioning by short-circuiting an input terminal and an output terminal; a delay element, mounted in the heating automat and acting by a regulator of the second stage of the burner on a single-wire control relay which, under voltage, controls by its reversing contact a direction of rotation of the drive motor, and, without tension, controls the other direction of rotation; and an undervoltage relay which, upon restoration of the voltage after a failure, moves the air shutter to its closed position, said control being characterized in that in addition to the short-circuited switches (28, 43) circuiting the input and output terminals (10 and 13), means (40, 41, 43, 45) are   provided for the further rotation of the engine   during the short-circuiting by the switch (28, 43), so that the position of the air shutter corresponding to the first stage of the burner is determined solely by an auxiliary switch (29) of the drive motor ( 22), which acts in the closing direction of the air shutter.   2. Air shutter control according to claim 1, characterized in that a rest contact (40) of the single-wire control relay (24) is inserted into a connection (6) of a phase wire (L), in the actuator of the air shutter (3, 4, 5), and an inverter (41) of the undervoltage relay (19) connects, in its rest position, the single-wire control relay (24) to the input terminal (10) that   the phase wire (L) feeds via a first regulator   (7) and a safety contact (8) in the heating automaton (1), while a working contact of the inverter (41)   is connected to the regulator (14) of the second stage of the burner.   3. Air shutter control according to claim 2, characterized in that a switch (26, 28) determining the maximum open position of the air shutter during the pre-purge time simultaneously energizes the undervoltage relay (19). ) whose connection   (42) is not energized until the end of the preven-   tion; and the undervoltage relay (19) can only be maintained powered by the same connection (42), a self-sustaining contact (43) and the input terminal (10).   An air shutter control according to claim 3, characterized in that the switch bypassing the input and output terminals (10 and 13) is an auxiliary switch (28) of the drive motor (22), reacting before the shutter is fully open   air; and the limit switch (26) responsive to the   the entire air shutter is embodied as an inverter whose inverter contact (26a) is connected to the connection (42) of the undervoltage relay (19), whose self-contact contact (43) connects the connection (42) to the output terminal (43) when said relay (19) is powered.   5. Air shutter control according to claim 3, characterized in that the switch bypassing the input and output terminals (10 and 13) is the self-holding contact (43) of the undervoltage relay ( 19) powered; and the limit switch (26) responsive to the total opening of the air shutter is embodied as an inverter, whose changeover contact (26a) is connected to the relay connection (42). voltage (19) and the output terminal (13).   An air shutter control according to claim 3, characterized in that the switch bypassing the input and output terminals (10 and 13) is an auxiliary switch (28) of the drive motor (22), responsive in a position of the air shutter intermediate between those corresponding to the first and second stage of the burner; the relay contact (43) of the relay to   lack of voltage (19) is in parallel with the auxiliary switch   liaire (28); and a connection is established between the connection (42)   the undervoltage relay (19) and the output terminal (13).