FR2541434A1 - INSTANTANEOUS GAS WATER HEATER - Google Patents

Abstract

INSTANTANEOUS GAS WATER HEATER INCLUDING A HEAT EXCHANGER HEATED BY A BURNER AND SUPPLIED WITH WATER THROUGH A GAS ADMISSION REGULATOR IN THE BOX WHICH ARE PLACED, IN THE DIRECTION OF WATER FLOW, A FLOW LIMITER AND A VENTURI, THE SPACE BETWEEN THE FLOW LIMITER AND THE VENTURI BEING CONNECTED TO A MEMBRANE CHAMBER, WHICH ACTS ON ONE OF THE MEMBRANE FACES, THE OTHER BEING IN COMMUNICATION WITH THE MEMBRANE VENTURI THROTTLE, TWO VENTURI BYPASS PIPES ARE PROVIDED WITH ONE PART DOWNSTREAM OF THE FLOW LIMITER AND IS CONTROLLED BY A VALVE ACTING ACCORDING TO THE POSITION OF THE DIAPHRAGM, WHILE THE OTHER STARTS UPstream OF THE LIMITER OF ' FLOW AND TERMINATES DOWNSTREAM OF THE HEAT EXCHANGER. FOLLOWING ONE VARIANT, THE OTHER BYPASS MAY ALSO END UPSTREAM OF THE HEAT EXCHANGER. FINALLY, IT IS ALSO POSSIBLE FOR THIS DUCT TO PUNCTURE THE FLOW LIMITER SHUTTER AND END DOWNSTREAM OF THE HEAT EXCHANGER.

Description

1 -

  The present invention relates to a water heater

  tantane gas with a heat exchanger

  by a breeder and supplied with water by the intermediary

  area of a gas inlet regulator in the casing of which are arranged, in the direction of flow of water, a flow limiter and a venturi, the space between the flow limiter and the venturi being connected to a membrane chamber, of which one of the two parts is

  closed by the membrane and the other connected to the choke

  venturi, two venturi bypass lines

  being planned, one of which is downstream of the speed limiter.

  flow and is controlled by a valve acting according to the position of the membrane, and the other comprises a valve

restriction.

  Such an instant gas water heater is known as

  the shape of the apparatus of the MAG-W type of the applicant.

  These devices, however, have the disadvantage

  the connection of the second

  venturi was performed downstream of the venturi, but upstream of the heat exchanger itself.

  all the water flows through the exchanger.

  This is disadvantageous in the sense that it is not possible

  ble to pass an unlimited amount of water to the water intake and the heat exchanger to supply the water intake pipe and thus offer the user the possibility of varying the water temperature even inside the beach

  nominal capacity of the water heater.

  The present invention aims to create this

opportunities.

  This goal is achieved by the fact that the other

  rivation begins upstream of the flow restrictor and

  ends downstream of the heat exchanger It is also

  if possible to vary the temperature of the water withdrawn even when the pressure of the supply water i of the distribution network is low Another goal is

  ensure the rapid start of the heat exchanger

  For this purpose, the first bypass line must be closed at rest, but open when the gas valve is open.

  is intended to achieve this conduct op-

  These goals are achieved by the fact that the limiter of

  flow being designed as a constant flow regulator

  the other bypass line starts downstream of the flow section of the regulator and passes through the regulator of this regulator and at its connection point

  upstream of the heat exchanger.

  An advantageous improvement consists in that the bypass line comprises an adjusting member

additional.

  Another improvement is given by the fact that

  constant flow regulator adjustment

  shape of a socket and touches, by one of its extremes

  the membrane and is housed at its other end in a bore of the gas admission regulator against

the return force of a spring.

  Another improvement is achieved by the fact that the housing of the adjustment member is part of a threaded plug screwed into a bore of the gas admission regulator and where the adjustment member is housed, the interior of this housing being connected by at least one radial bore to a pipe constituting the

bypass line.

  Another improvement is that

  radial wise has a triangular section, the triangle being arranged so that the closed section in the state of rest of the water heater opens with a tip of the triangle to be released successively to its entire extent.

  An exemplary embodiment is described in more detail.

254143-4

  below, using figures one to five of the

sin. From these figures,

  figure one schematically shows the way by

  what water flows in a gas instantaneous water heater, figure two, a diagram;

  Figure 3 presents another flow diagram.

  Water in a gas instantaneous water heater, according to a variant of the invention, Figure 4, an enlarged section of the gas inlet regulator, Figure 5, a detail of the intake regulator.

gas.

  In the five figures, the same figures designate

the same details.

  The gas instantaneous water heater 1, according to the figure

  one, includes as central element a heat exchanger

  their 3 is heated by a gas burner 2 and on which is connected, downstream, a water intake pipe 4 comprising a water intake valve 5 The cold water arrives according to a

  arrow 6, from the distribution network, in a

  7 which, inside a box, is provided

  a supply line 8 having a branch 9.

  From branch 9, a branch line 10 is connected

  roped directly to the water intake pipe 4, downstream of the heat exchanger 3 and upstream of the water intake valve 5 The bypass pipe 10 comprises an element

  11 and a valve 13 provided with a control member

  12 of the branch 9 part of a pipe 14,

  associated with the bypass line 10, which terminates

  to a non-removable flow limiter after

  Removal of a screw 16 Downstream of the flow restrictor there is provided a diaphragm chamber 17, enclosing a diaphragm 19 provided with a piston 18 and secured along its circumference 4 tightly in the housing so that

  this surrounds a vacuum chamber 20 and a chamber

  while the flow limiter

  15 gives access to the overpressure chamber 21, an outlet of this chamber is formed by a venturi 22 whose throttle 23 is the connection point of a

  pipe 24 connected to the vacuum chamber 20.

  The outlet of the venturi 22 is connected to a pipe 5 which puts the regulating device 7 in communication with one another.

  with the inlet of the heat exchanger 3 From the room

  pressure booster is part of a second

  26, via a valve seat 27 which is still part of the overpressure chamber 22 of the adjusting device 7 The bypass line 26

  opens at point 33 in line 25, between the

  and the heat exchanger The valve seat 27 is occupied by a conical shutter 28 which, by a rod

  29 cooperates with the piston 18 With the piston 18 is solid-

  another stem 30 which carries a shutter 31 forming part of a gas valve disposed on a pipe

  gas supply, connected to the burner 2.

  Figure two shows a graph showing

  firing the water flow in dm 3 min 1 according to the pressure

  P respectively of the At temperature increase

in OC.

  The operation of the instantaneous water heater, object of figure one, is now explained in more detail

  using figure two Let's suppose the device to be

  stopping state; that is to say that the adjusting member 11 is half open, the water tap 5, the valve 13,

  the valve 27/28 and the gas valve 31 being closed.

  There is no gas flow or water.

  If, to start up the water heater, the water

  binet 5 is open, it establishes a cou-

  water flow limited by the effect of the flow limiter, through the overpressure chamber 21, the venturi, the pipes 25 and 4 and the heat exchanger 3. As a result, via the pipe 24, the depression born at the venturi is communicated to the membrane chamber 20 which causes the lifting of

  the diaphragm 19 against the thrust of a spring 76

  removal of the diaphragm causes, via the rod 30, the release of the shutter 31 of its

  seat and thereby the opening of the gas valve.

  At the moment, however, when the gas valve is opened, the valve 27/28 is also open, thereby disengaging the bypass line 26.

  progressive so that by the effect of the conduct of

  rivate, an increase in the flow of water results in a lower pressure at the venturi, which has the consequence that the opening of the gas valve is

  proportional to the flow of water, but increases less

  All of the water flowing through the venturi and the bypass line 26 is heated in the heat exchanger 3 and arrives through the pipe 4 to the water intake valve. is

  possible to make available directly to the

  a water quantity regulated by the valve and the adjusting member 13, 11 and

  not having passed through the heat exchanger.

  The graph of FIG. 2 first shows a beam of curves 40, 41, 42 and 43 starting from zero and representing water flow rates as a function of the pressures provided by the distributor network. This is how we obtain the curve 40 for a water pressure of 6 bar if the valve is opened more or less 13 From the curve the flow of water flows through the bypass pipe, for a given maximum water pressure. maximum water of four bars gives the curve 41, a pressure of

a bar, the curve 43.

6 -

  Curve 44 is the characteristic of the limiter of

  For a water pressure of 0 to 1 bar, the curve rises rapidly from zero to a point 45

  to continue then almost horizontally

  after a water pressure greater than one bar has no effect on the flow through lines 14 and 25

and the heat exchanger.

  The curve 47 is born from the addition of the curve 40 with the corresponding curve 44. The other curve 47 results from

  the addition of the curves 42 and 44 The curves 46 and 47

  weave at the level of the maximum temperature increase typical, that is to say 25 OC, or that of the maximum flow of 10 dm 3 min. Curves 46 and 47 show that by variation

  the flow of water in the bypass line 10 to the

  of the valve 13, it is possible to vary both the increase

  temperature and hence the temperature of the water withdrawn as the flow as a function of the pressure of the

distributor network.

  The adjusting member is intended for adjusting a

  average bit during the installation of the device, taking into account the pressure of the network, which is admitted as maximum bypass flow The user can, by means of the valve 13,

  reduce this flow, but never increase it.

  If the intake valve 5 has an inferior section

  at the throttle limit section of the flow limiter

  15, the flow curve varies with

  valve until the moment the limiter

  flow enters into action This curve is the curve 48

  of Figure Two Point 45 of this curve marks the

  in action of the limiter, from which the de-

  bit of water is constant or nearly constant, following curve 44, regardless of the opening of the valve

water intake.

  If then the valve 13 is opened by handling the

  12, there is established in line 10 a throughput of -7-

  the limiter 15 does not influence This flow of water can

  may be enlarged or reduced with the help of the valve 13 If the flow section of the valve 13 is no longer

  smaller than the one to which the adjustment organ is

  stage 11, it is the valve 13 which determines the bypass flow rate. If the section of the valve is larger, the

  total water flow rate is regulated by the adjusting member 11.

  When the flow section of the valve is more

  tite, the result is a curve like curve 49

  At point 50, it is here that the flow limiter comes into action again, which causes the curve 49 to bend, which is prolonged by the curve 46. The whole of the curve 49/46 results from the addition. curves 48 and

  44 with one of the curves 40 to 42, the latter do not

  presenting that the flow of the diversion The inclination

  its different curves 40 to 42 is determined by the smallest section of the valve and the organ

adjustment of the derivation.

  If the user has established a tuning feature that best suits him, the adjusting member 11 is adjusted so that this characteristic is

  obtained by adjusting the valve 13 with the aid of

  manual control 12 This section and the curve

  are thus definitively established for the apparatus L'u-

  The user can reduce the bypassed cold water flow by varying the position of the valve. 13 In this case,

  the flow of water passing through the heat exchanger does not

  The consequence of such a reduction is therefore an increase in the temperature of the water withdrawn

  using the water tap, the total flow rate

so diminished.

  But the same result can also be achieved by

  the positions of the organs 11 and 13-unchanged and in

  the flow through the water tap 5 provided that the flow through the heat exchanger

  of heat 3 is essentially determined by the

  flow 15, the decrease at the tap

  water intake 5 causes only a variation (decrease

  The consequence is also an increase in the temperature of the water

  lift, the flow of the tap decreasing only slightly.

  This solution has the advantage that the user can

  vary the temperature of the water withdrawn (in

  variable) by simply varying the opening

ture of the water tap.

  We would have the curve 47 of figure two if the pres-

  the supply water only amounted to 2 bars, because this value is already established

  the nominal water flow curve 47 is again obtained

  by the addition of curve 44 with curve 42.

  The instantiated gas water heater shown in

  figure three and used for the preparation of sanitary water.

  re, understands as a central element a heat exchanger

  their 3 heated by a gas burner 2 and provided, downstream, a water intake pipe 4 comprising a water tap 5 Cold water flows along an arrow 6 from a distribution network to a gas admission regulator 7 This, in a stacker, includes a pipe

  8 with a connection 9 From this branch-

  part of a diversionary line 10 which, as

  3 shown in broken lines, is connected directly to the water intake pipe 4, downstream of the heat exchanger 3 and

  upstream of the water intake valve 5

  10 comprises an adjusting member 11 and a valve 13 provided with a manual control member 12

  9 parallel conduct to the conduct of debris.

  10, which undergoes the action of a constriction 60 formed by a narrowing in the housing 7 on the one hand and a shutter 61 of a constant flow regulator 62, -9

  On the other hand, on the side of the choke 60, do not

  not keeping the connection 9, the conduit 14 passes through a membrane chamber 17 o is sealed by its edge, a membrane 19 provided with a piston 18 so as to form, in the housing, a vacuum chamber 20 and an overpressure chamber 21 The throttling of the constant flow regulator forming the inlet of the overpressure chamber, an outlet of this chamber is made by a venturi 22 At the throttle 23 of it opens a pipe 24 which leads to the

vacuum chamber 20.

  At the outlet of the venturi 22 is connected a pipe 25 which connects the gas admission regulator 7 to the inlet

  of the heat exchanger 3 From the sur-

  pressure 21 leaves a second bypass pipe 26

  through an orifice 63 and a central bore 64 in the closure

  61, downstream of the throat 60 of the regulator 62,

  to connect the overpressure chamber, avoiding the

  turi, at the pipe 25 by the connection 33 being

  downstream of the venturi, but upstream of the heat exchanger

their.

  The shutter-shaped adjustment member 61 is solidly

  with the piston 18 by its extension containing the o-

  63 and the central bore 64 From the opposite side, the

  61 consists of a socket 65 where is housed a thrust spring 66 seated on a support 67 integral with the housing. With the diaphragm chamber 17 and the regulating member 61, the venturi 22 forms a constant flow regulator

  whose pilot size is given by the opening of the

  water intake tap 5 That is, the water flow determined by the opening of the water tap 5

  is kept constant by the regulator.

  According to another variant of the invention, it is possible to connect the bypass line 10 not, as shown in broken lines, to the intake pipe 4, downstream of the heat exchanger 3, but, as shown in solid lines, to driving

  upstream of the heat exchanger 3.

  The br 2 is fed by a gas pipe 32 which comprises a valve 31 The shutter of this valve 31 is controlled by a rod 30 attached to the piston 18 on its non-facing side. The configuration is shown in FIG. As a result, the lower part of the 68 th pinned and screwed together, the membrane feels a passage 70 o the water, the stem 30 I

the adjusting member 61.

of the gas admission regulator

  who shows the active position

  this regulator consists of a t of an upper part 69,

one over the other and squeezing together

19 The upper part 69 pre-

slide, gas-tight and

  piston 18 is supported, through

  a thrust spring 76, on the lower face of the upper part 69 so that he and thereby the membrane tend to put themselves in the low end position Against the lower face of the membrane applies the t 9 72 of the adjusting member 61 on which the return spring 66 acts The spring return constant 66 is smaller than that of the spring 71 so that the latter overcomes the effect of the other. at rest, the gas valve 31 is closed, but the member 61 disengages the flow section 60 of the constant flow regulator The seat 67 is designed in the form of a screw placed in a bore 73 of the housing 68 A the bore 73 is connected to the pipes 8 and 26. The screw-seat of its head is in the form of a bush and has a hollow 74 which, via a radial hole 75, communicates with the inside of the bore which is the pipe 26 On its outer wall, the seat screw carries an O-ring seal to the inner wall of the bore 73, and the inner wall of the bore 74

11 2541434

  is provided with O-rings to seal against the outer wall of the adjustment member 61 housed therein.

  between the arrival tube 8 and the pipe 25, through

  intermediate of the flow section 60 set by this

  member 61, bores 63 and 64 within the housing

  61, the bore 74 and finally the radial hole and the pipe 26 downstream of the venturi This pipe, which bypass the throat 23 of the venturi 22, is controlled as to its flow section, on the one hand by the flow section 60 set by the member 61, and on the other hand by the hole 75 which can be closed by the sleeve 65 At rest, the hole 75 is closed by the sleeve 65, the flow section In the other extreme position, the flow section 60 is closed by the adjusting member 61, but the hole 75 is open, the sleeve 65 having disengaged it by axial movement. FIG. 4 shows a state of operation of the regulator o the tap 5 is open At rest, a state represented by FIG.

  26 is closed As a result, to start the ap-

  the same, the entire flow of water must pass through

  towards the open flow section At the time when the valve 5 is open, there is therefore in the chamber 21 an overpressure which is reduced in part by the action of the

  venturi 22, partly by the bypass line 10.

  The speed at which this reduction of the overpressure occurs depends on the flow section of the valve 13 If the latter is closed, the overpressure is destroyed by the sole effect of the venturi which results in the formation of a pressure high differential in both diaphragm chambers The consequence is a very fast reaction of the gas inlet regulator and the equally rapid opening of the gas valve, the

- 254143 4

  12 - membrane 19 being moved suddenly against the action of the spring 71 Under the action of the spring 66, the adjusting member 61 follows the movement of the membrane and thus reduces the flow section 60 But, the displacement of the member 61 also has the effect of disengaging the bypass line 26 so that water is diverted in part from the venturi 22 which causes a partial reduction of the differential pressure between the diaphragm chambers. This means that immediately after the movement in order to open the gas valve, the gas flow proportionally follows the flow of water,

  but the proportionality factor is greater than 1.

  In parallel, it is possible to open more or less bypass line 10 by the handling of the member 12 In this case too, the venturi 22 is bypassed which has the consequence that the proportionality factor

can still be reduced.

  FIG. 5 shows the configuration of the seat 67 and the radial hole 75 which it carries. The seat 67 is a stepped cylindrical element which has a first portion 77 in the form of a bushing. This hollow part encloses the wall with its internal wall. Outer ring of the sleeve which is part of the adjusting member 61 An O-ring 78 fixed on the outer wall of the part 77 seals against the inner wall of the bore 73 The hole 75 is arranged between the end 79 of the portion 77 and the first shoulder 80 which is followed by a portion 81 with a larger diameter, provided with a thread

  82 allowing to screw the seat in the tapping that com

  The portion 81 is followed, after another shoulder 83, the final portion 84 of the seat 67, which has the largest diameter and which can have a polygonal shape to allow to screw all in

  the gas admission regulator 7.

  As can be seen from the figure, hole 75 is not

-2541434

  13 - cylindrical but approximately triangular The triangle is arranged so that by a displacement of the lower edge of the sleeve 65, firstly the tip of the triangle is disengaged so that continuing its upward movement, the socket 65 gradually releases the section

of the hole 75.

  It is possible to provide in the seat 67 a single triangular hole 75 or more holes of this kind. The tip angle of the triangle must be adapted to the characteristics of the water heater. It is from this angle that the proportionality factor depends. which determines the flow variation

of gas depending on the flow of water.

  Of course, it is also possible to predict, contrary

  In the example of FIG. 4, the bushing 65 constitutes the inner element and the seat, the outer element, the bushing 65 as the outer element and the seat 67 as the inner element. The same result is obtained from analogous way when the triangular hole is arranged in the socket and covered more or less

forgiveness edge of the seat.

Claims (6)

claims   1 Instant gas water heater with an   Heat of heat heated by a burner and fed   in water through a regulator of   gas in the casing of which are arranged in   the flow direction of the water, a flow limiter   and a venturi, the space between the speed limiter and   flow and the venturi being connected to a chamber   membrane, which acts on one of the faces of the mem-   brane, the other being in communication with   Venturi branch, two venturi bypass pipes are planned, one of which is downstream of the   flow limiter and is controlled by a   poppet acting according to the position of the membrane, and the other comprises a valve, characterized in that the other bypass line (10) starts upstream of the flow limiter (15) and ends   downstream of the heat exchanger (3).   2 gas instantaneous water heater according to the   tion one, characterized by the fact that   branching device (10) comprises an adjusting member (11).   3 Instant gas water heater with an exchange   heat generator heated by a burner and fed   in water through a regulator of   gas in the casing of which are arranged in   the flow direction of the water, a flow limiter   and a venturi, the space between the speed limiter and   flow and the venturi being connected to a diaphragm chamber, which acts on one of the faces of the membrane, the other being in communication with the throat of the venturi, two venturi bypass lines being provided, one of which downstream of the limiter   flow and is controlled by a   depending on the position of the membrane, and the other   carries a valve, characterized by the fact that   flow limiter being designed as a regula-   constant flow rate (62), the other   rivation (10) begins downstream of the flow section.   (60) of the regulator (62), passes through the regulating member (61) of the regulator (62) and at its   connection upstream of the heat exchanger (3).   4 Instant gas water heater with an exchange   heat generator heated by a burner and fed   in water through a regulator of   gas in the housing of which are arranged, in   the flow direction of the water, a flow limiter   and a venturi, the space between the limiter   flow and the ventur being connected to a chamber   membrane, which acts on one of the faces of the mem-   brane, the other being in communication with   venturi, two branch pipes of the Venturi are planned, one of which is downstream of the   flow limiter and is controlled by a   poppet acting according to the position of the membrane, and the other comprises a valve, characterized in that, the flow limiter being designed as a constant flow regulator (62), the other bypass line (10) starts in downstream of the flow section (60) of the regulator (62), passes through the regulator (61) of this regulator and has its   connection point downstream of the heat exchanger their (3).   Gas instantaneous water heater according to claim 3 or 4, characterized in that the regulating member (61) of the constant flow regulator (62) is in the form of a socket and is touched by one its ends (72), the membrane (19) and   is housed at its other end in a bore   ge (74) of the gas admission regulator (7), against   the return force of a spring (66).   6 Instant gas water heater according to one of the   three to five, characterized in that the housing (74) of the adjusting member (61) is part of a threaded plug (67) screwed into a   bore (73) of the gas admission regulator (7).   and where the adjustment member (61) is housed, the   the bore (74) being connected by at least   a radial bore (75) to a pipe constituting   the bypass line (26).   Gas instantaneous water heater according to Claim 6, characterized in that the radial bore   (75) has a triangular section, the triangle being   placed so that the bore (75) closed in the state of rest of the water heater opens with a tip of the triangle to be cleared successively to its full extent.