EP4100680A1

EP4100680A1 - Gas-air mixer

Info

Publication number: EP4100680A1
Application number: EP21716244.5A
Authority: EP
Inventors: Berrin KARAUZUM; Yalcin OTER; Cevat Erkin TEKIN
Original assignee: Emas Makina Sanayi AS
Current assignee: Emas Makina Sanayi AS
Priority date: 2021-01-21
Filing date: 2021-02-19
Publication date: 2022-12-14
Anticipated expiration: 2041-02-19
Also published as: WO2022159051A1; EP4100680B1; TR202100913A2

Abstract

The present invention relates to a gas-air mixer (venturi) (1) which is used to transfer gas and air into the combustion chamber in gas burning devices such as boilers upon mixing thereof, comprising at least one outer body (2) which has at least one gas inlet (21) for gas transfer to its inner part and has a volume inside, at least one inner body (3) which is placed inside the outer body (2), comprises an inlet for air passage and an outlet for air-gas mixture, and at least one opening (33) for gas passage therein from the outer body (2), at least one turbulator (4) and/or valve system (5) which is positioned on the air inlet of the inner body (3) and used for making the air turbulent and/or adjusting the air passage amount.

Description

GAS-AIR MIXER

Field of the Invention

The present invention relates to a modular gas-air mixer which is used to transfer gas and air to the combustion chamber upon mixing thereof.

Background of the Invention

In gas burning devices such as boilers, the combustion products (gas and air) are mixed by the fan and gas-air mixer and sent to the combustion chamber. Since the gas-air mixture formed in this way is supplied homogeneously, all or almost all of the gas burns. With the pre-mixing fan used in gas burning devices, air and gas are sucked and the gas-air mixture is blown into the burner. Electronically or pneumatically adjustable gas valves are used to adjust the mixing ratio. In systems with pneumatic gas valves, the gas valve provides gas flow with the effect of negative pressure and the gas is directly mixed into the sucked air. In the prior art, gas-air mixers are comprised of a chamber, an air passage channel for the passage of air through the chamber, a gas inlet opening into the chamber and a plurality of holes located on the air passage channel. While the air passes through the air channel, the gas enters the chamber. Gas mixes with air by passing through the holes on the air passage channel. Depending on the flow of the sucked air, the gas mixes at an appropriate rate and the air + gas mixture required for combustion is formed. Here, it is a known method that the negative pressure (the vacuum effect) is obtained by means of a venturi arranged on the suction side of the fan, wherein a locally higher flow velocity and negative pressure are obtained by locally reducing the flow cross-section (Bernoulli-equation). In the state of the art, the air passage channel is comprised of two conical cylindrical parts which are separate from each other and are joined afterwards, and the holes used for gas passage are located at the joints of the said two parts. In the current technique, different gas-air mixer configurations must be used in order to make modulations of boilers with different energy levels. For example, the gas-air mixer that should be used for a 24 kW boiler and the gas-air mixer that should be used for a 45 kW boiler are different from each other. Therefore, it is required to use a different mixer for boilers with different capacities. This situation causes the production of gas-air mixers to be more complex. Since the gas-air mixers used in the current technique do not comprise common parts, they need molds different from each other. This situation creates the need for using different molds for boilers at different energy levels for mass production of gas-air mixers, and creates problems such as continuous mold change and decrease in labor times and thus increase in production costs. It should provide the same ideal mixture at different fan speeds of gas-air mixers.

International patent document no W02018015130A1, an application known in the state of the art, discloses a gas-air mixing device comprising an air inlet channel body including a narrowing section, an air outlet channel body, and which is comprised of extension openings provided on the air outlet channel body. In the said application, for the passage of the gas into the air passage channel, the invention comprises two conical cylindrical parts with different diameters in the part where they are connected to each other and the gas passes through the extension openings at the junction part of the said two parts. The said application cannot be used for gas burners (boilers, etc.) with different energy levels; a separate mixer must be prepared for each energy group (24 kW, 45 kW, etc.). The structure in the said application does not allow the modulation rate to be changed according to the demand of the device.

International patent document no DE202018106411U1, an application known in the state of the art, discloses a gas-air mixing device comprising an air inlet channel body including a narrowing section, an air outlet channel body, and which is comprised of extension openings provided on the air outlet channel body. In the said application, for the passage of the gas into the air passage channel, the invention comprises two conical cylindrical parts with different diameters in the part where they are connected to each other and the gas passes through the extension openings at the junction part of the said two parts. The said application cannot be used for gas burners (boilers, etc.) with different energy levels; a separate mixer must be prepared for each energy group (24 kW, 45 kW, etc.). The structure in the said application does not allow the modulation rate to be changed according to the demand of the device.

In National Patent application no 2019/18395, an application known in the state of the art, there is an air mixer comprising a narrowing section. The said application cannot be used for gas burners (boilers, etc.) with different energy levels; a separate mixer must be prepared for each energy group (24 kW, 45 kW, etc.). The said application cannot be used for different gas families; it is required to prepare a different mixer for each gas family (G20, G31 etc.).

In International Patent Application no EP2653215B1, known in the state of the art, there is an air mixer comprising two narrowing sections and a structure which can change the air and gas inlet according to the load in one of the channels. Different from the said application, adjustment of the gas intake amount of a single venturi nozzle can be provided. In the aforementioned application, springs are used to provide modulation and this shortens the life of the product due to the problems that may arise due to the change of the spring properties over time. The said invention also cannot be used for different gas families; it is required to prepare a different mixer for each gas family (G20, G31 etc.).

Summary of the Invention The objective of the present invention is to provide a gas-air mixer which is modular for gas burning devices with different energy levels in which they are to be used and whose capacity can be changed without changing its interior part.

The objective of the present invention is to provide a gas-air mixer, which enables to increase the modulation rate of the product by keeping the minimum fan speed of the device at a range in which the fan of the device can operate safely, and in which the amount of the incoming air can be changed.

The objective of the present invention is to provide a gas-air mixer which allows the air passage to be more turbulent and therefore to increase the amount of gas in the mixture without increasing the pressure loss of the product.

The objective of the present invention is to provide a gas-air mixer which has low pressure loss.

The objective of the invention is to increase the modulation level with a modular structure while keeping the minimum fan speed within the safe range in which the fan can operate without increasing the maximum fan speed, and thereby preventing the high noise level caused by the high maximum fan speed.

Detailed Description of the Invention

The gas-air mixer developed in order to achieve the objectives of the present invention is illustrated in the accompanying figures, in which:

Figure 1 is the front perspective view of the gas-air mixer of the present invention with turbulator.

Figure 2 is the front cross-section view of the gas-air mixer of the present invention without valve system or turbulator.

Figure 3 is the front cross-section view of the gas-air mixer of the present invention with turbulator. Figure 4 is the side cross-section view of the gas-air mixer of the present invention.

Figure 5 is the front perspective view of the valve system in the gas-air mixer of the present invention.

Figure 6 is the rear perspective view of the valve system in the gas-air mixer of the present invention.

Figure 7 is the front perspective view of the turbulator in the gas-air mixer of the present invention.

Figure 8 is the rear perspective view of the turbulator in the gas-air mixer of the present invention.

The components shown in the figures are each given reference numbers as follows:

1. Mixer

2. Outer body

21. Gas inlet

22. Lock channel

3. Inner body

31. Inlet channel

311. Mounting surface

32. Outlet channel

33. Opening

35. Slot

4. Turbulator

41. First ring

42. Center part

43. Blade

45. First lug

5. Valve system

51. Second ring 52. Pin

53. Flap

54. Second mounting elevation

55. Second lug

6. Sealing member

A mixer (1), which is used to transfer gas and air into the combustion chamber in gas burning devices such as boilers upon mixing thereof, comprises at least one outer body (2) which has at least one gas inlet (21) for gas transfer to its inner part and has a volume inside, at least one inner body (3) which is placed inside the outer body (2), comprises an inlet for air passage and an outlet for air-gas mixture, and at least one opening (33) for gas passage therein from the outer body (2), at least one turbulator (4) and/or valve system (5); which is used for allowing to increase the modulation rate of the device and to increase the minimum fan speed of the device by increasing the maximum fan speed, at which the device can operate, by a minimum amount; and which is placed on the air inlet of the inner body (3) and used for making the air more turbulent or adjusting the air passage amount.

The mixer (1) of the present invention is comprised of an outer body (2) into which gas is transferred through a gas inlet (21), an inner body (3) in the form of a cylinder which is placed inside the outer body (2) and comprises air inlet-outlet, openings (33) which are provided on the inner body (3), and the turbulator (4) or valve system (5) which is located on the air inlet of the inner body (3). The outer body (2) located in the mixer (1) is preferably in the form of a cylinder that is open at both ends and there is a gas inlet (21) in the form of a hole, preferably on the middle part of the outer body (2). The inner body (3) located in the mixer (1) comprises parts, the section of which narrows and expands, and it has an opening (33) in the form of a hole preferably where the section is narrow. There is a turbulator (4) and/or valve system (5) at the air inlet part of the inner body. Both the turbulator (4) and the valve system (5) have the same purpose and allow to increase the modulation rate of the device and to increase the minimum fan speed of the device by increasing the maximum fan speed, at which the device can operate, by a minimum amount. The turbulator (4) and/or the valve system (5) makes the air which will enter into the inner body (3) more turbulent without changing the fan (which transfers the air to the inner body (3)) or by increasing its speed at a minimum level, and in this way, it enables to increase the amount of gas in the mixture without increasing the pressure loss of the product. Therefore, for gas burning devices having different energy levels (24 kW, 45 kW boiler, etc.), a single mixer (1) can be used without changing the inner body (3) and outer body (2), only by changing the valve system (5) and/or the turbulator (4). Thus, it is possible to provide the air-gas mixture of the boilers with different energy needs by changing only the turbulator (4) and/or the valve system (5) during production. In addition, this minimizes labor and mold costs, and also reduces mass production costs. Since different modulation rates can be provided easily with the modular structure, it also reduces inventory costs.

In the mixer (1) of the present invention, only the turbulator (4) and/or the valve system (5) are changed according to the boiler energy level after mounting of the outer body (2) and the inner body (3) in the production. The air first comes onto the turbulator (4) and/or the valve system (5) on the inner body (3), and the air moves in the inner body (3) upon becoming turbulent in the turbulator (4) and/or the valve system (5) and/or in a desired amount of passage. The gas is filled into the outer body (2) through the gas inlet (21) on the outer body (2) and the gas flows into the inner body (3) through the opening (33) according to the Bemoulli- equation (negative pressure state with high flow velocity due to narrowing section in the inner body (3)), and mixes with the air.

In one embodiment of the present invention, the inner body (3) is comprised of air inlet channel (31) and outlet channel (32), which are a single piece, and openings (33) located at the junction of the air inlet channel (31) and the air outlet channel (32). The air inlet channel (31) is comprised of the flat mounting surface and the narrowing section, and the outlet channel (32) section has a conical structure with an expanding section. The turbulator (4) and/or the valve system (5) are placed on the flat mounting surface on the air inlet channel (31). In this way, before the air reaches the narrowing section structure, it is regulated by the turbulator (4) and/or the valve system (5), it becomes a turbulent flow and/or the amount of air passage is determined and the noise and poor quality combustion that may occur in different gases is prevented. The regulated flow prevents poor quality combustion caused by the gas quality.

In one embodiment of the present invention, the air inlet channel (31) has a mounting surface (311) extending outward from the outer body (2) and when the inner body (3) is placed inside the outer body (2), the mounting surface (311) remains outside the outer body length. In this way, the turbulator (4) and/or the valve system (5) is fixed on the inner body (3) mounting surface (311) outside the outer body (2). In this way, the turbulator (4) and/or the valve system (5) can be easily detached from and attached to the inner body (3) and outer body (2).

The minimum load and maximum load ratio which the mixer (Venturi) (1) can provide in gas burning devices is called the modulation ratio. Since the mixer (venturi) (1) provides the gas mixture, it enables the maximum possible gas ratio to be determined. The device has a modular venturi structure so that it can operate in different modulation ranges in different models. The said modulation range is adjusted with the turbulator (4) and/or the valve system (5).

In one embodiment of the invention, the turbulator (4) comprises: at least one first ring member (41) in order to be fixed to the air inlet part of the inner body (3), a center part (42) which is provided preferably on the middle part of the first ring member (41) and a plurality of fixed blades (43) which are positioned between the center part (42) and the first ring member (41).

A turbulator (4), which is used by being fixed to a mixer (1) wherein gas and air are mixed in the combustion chamber in gas burning devices such as boilers and the like, and which is used to transfer the air with turbulence, is comprised of at least one first ring member (41) in order to be fixed to the air inlet part of a mixer (1), a center part (42) which is provided preferably on the middle part of the first ring member (41) and a plurality of fixed blades (43) which are positioned between the center part (42) and the first ring member (41).

The said fixed blades (43) of the turbulator (4) are fixed at an angle according to the air intake direction. The turbulator (4) is fixed/positioned on the air inlet side of the inner body (3) via the first ring element (41), and the blades (43) are positioned in the air intake direction so that the air passage becomes more turbulent and thus the gas ratio in the mixture is enabled to be at the desired ideal amount without increasing the pressure loss of the product.

In one embodiment of the present invention, the turbulator (4) comprises a first mounting elevation which is in the form of a circular protrusion for attaching the first ring member (41) to the mounting surface (311). The said first mounting elevation is positioned on the outer wall of the inner body (3) and thus enables the turbulator (4) to be fixed.

In one embodiment of the present invention, there is at least one first lug (45) or second lug (55) part which is in the form of a protrusion or ridge on the first mounting elevation or the second mounting elevation (54), and which comprises a hole thereon matching a connection protrusion (movable/push-on) located on the outer wall of the inner body (3). During mounting, the push-on protrusion on the outer wall of the inner body (3) is inserted into the hole and when the hole and the push-on connection protrusion match, the protrusion fits into the hole.

In another embodiment of the present invention, the turbulator enables the air intake amount to be determined by narrowing the air inlet in cross-section. The turbulator makes the intake air more turbulent.

In one embodiment of the invention, the valve system (5) comprises a second ring member (51) in order to be fixed to the air inlet part of the inner body (3), at least one rotary pin (52) which is fixed on the second ring member (51), at least one flap (53) which is fixed to the rotary pin (52) and is movable with the rotary pin (52).

A valve system (5), which is used by being fixed to a mixer (1) wherein gas and air are mixed in the combustion chamber in gas burning devices such as boilers and the like, and which is used in order to increase the modulation rate (decreasing the minimum capacity) and to transfer the air with turbulence, comprises a second ring member (51) in order to be fixed to the air inlet part of a mixer (1), at least one rotary pin (52) which is fixed on the second ring member (51), at least one flap (53) which is fixed to the rotary pin (52) and is movable with the rotary pin (52).

A valve structure is formed with the pin (52) and the flap (53) provided in the valve system (5) and the opening ratio of the flap (53) enables the modulation rate (capacity) of the mixer (1) to be determined. In one embodiment of the present invention, there is at least one head which is used for rotating the pin (52) and is located in the part of the pin (52) outside the inner body (3). In one embodiment of the present invention, the pin (52) is fixed in a rotatable manner by fitting into the opposite holes on the inner body (3).

In the mixer (1) of the present invention, by means of the turbulator (4) and/or valve system (5), the amount of turbulence in the air inlet is increased and it is enabled to increase the minimum fan speed of the device by increasing the maximum fan speed, at which the device can operate, by a minimum level. The turbulator (4) and/or the valve system (5) (the turbulator part) allows the modulation rate of the device which is 1:4 to be 1:6 or 1:8.

In one embodiment of the present invention, there is at least one sealing member (6) which prevents the gas entering the inner part of the outer body (2) from leaking (exiting) between the inner wall of the outer body (2) and the upper surface of the inner body (3). In one embodiment of the invention, the sealing member (6) is a gasket or an O-ring.

In one embodiment of the present invention, there is at least one slot (35) which is formed with protruding surfaces on the outer surface of the inner body (3) and in which the sealing member (6) fits.

In one embodiment of the invention, a fixing assembly used in fixing the inner body (3) on the outer body (2) comprises at least one lock pin in the form of a protrusion which is provided on the outer surface of the inner body (3), at least one lock channel (22) which is provided at the end part of the outer body (2) in the form of an inclined channel recess on the outer body (2) and is adapted for the lock pin to be inserted therein.

The fixing assembly is used to fix the inner body (3) on the outer body (2) and comprises a pin-channel structure (bayonet). By rotating the inner body (3) clockwise together with the fixing assembly, the sealing members (6) provide sealing between the bodies. With the lock mechanism, the inner body (3) is prevented from reverse rotation and the integrity of the equipment is protected against vibrations that occur when the device is carried and the fan operates.

A mixer (1), which is used to transfer gas and air into the combustion chamber in gas burning devices such as boilers upon mixing thereof, comprises at least one outer body (2) which has at least one gas inlet (21) for gas transfer to its inner part and has a volume inside, at least one inner body (3) which is placed inside the outer body (2), comprises an inlet for air passage and an outlet for air-gas mixture, and at least one opening (33) for gas passage therein from the outer body (2), at least one turbulator (4) which is used for making the air more turbulent and which is comprised of

• a first ring member (41), a center part (42) preferably located on the middle part of the first ring member (41), and a plurality of fixed blades (43) positioned between the center part (42) and the first ring member (41), at least one valve system (5) which enables to determine the modulation rate (capacity) and to decrease the minimum fan speed at which the product can operate, and which is comprised of

• a second ring member (51) in order to be fixed to the air inlet part of the inner body (3),

• a rotary pin (52) on the inner body (3) air inlet and at least one flap (53) which is fixed to the rotary pin (52) and is movable with the rotary pin (52).

Claims

CLAIMS . A mixer (1), which is used to transfer gas and air into the combustion chamber in gas burning devices such as boilers upon mixing thereof, characterized by

- at least one outer body (2) which has at least one gas inlet (21) for gas transfer to its inner part and has a volume inside,

- at least one inner body (3) which is placed inside the outer body (2), comprises an inlet for air passage and an outlet for air-gas mixture, and at least one opening (33) for gas passage therein from the outer body (2),

- at least one turbulator (4) which is used for increasing the amount of turbulence in the air inlet, increasing the modulation rate of the device and increasing the minimum fan speed of the device by increasing the maximum fan speed at which the device can operate in a minimum amount, and which is comprised of

• at least one first ring member (41) in order to be fixed to the air inlet part of the inner body (3),

• a center part (42) which is provided preferably on the middle part of the first ring member (41) and

• a plurality of fixed blades (43) positioned between the center part (42) and the first ring member (41). . A mixer (1), which is used to transfer gas and air into the combustion chamber in gas burning devices such as boilers upon mixing thereof, characterized by

- at least one inner body (3) which is placed inside the outer body (2), comprises an inlet for air passage and an outlet for air-gas mixture, and at least one opening (33) for gas passage therein from the outer body (2), at least one valve system (5) which enables to keep the minimum fan speed of the device at a safe range in which the fan can operate by increasing the maximum fan speed at which the product can operate at minimum level to determine modulation rate (minimum capacity of the device), and which is comprised of

• at least one rotary pin (52) which is fixed on the second ring member (51),

• at least one flap (53) which is fixed to the rotary pin (52) and is movable with the rotary pin (52). A turbulator (4), which is used by being fixed to a venturi mixer (1) wherein gas and air are mixed in the combustion chamber in gas burning devices such as boilers and the like and which is used to transfer the air with turbulence, characterized by at least one first ring member (41) in order to be fixed to the air inlet part of a mixer (1), a center part (42) which is provided preferably on the middle part of the first ring member (41) and a plurality of fixed blades (43) which are positioned between the center part (42) and the first ring member (41). A valve system (5), which is used by being fixed to a mixer (1) wherein gas and air are mixed in the combustion chamber in gas burning devices such as boilers and the like and which enables to determine modulation rate (minimum capacity) and to decrease the minimum capacity at which the product can operate, characterized by a second ring member (51) in order to be fixed to the air inlet part of a mixer (1), at least one rotary pin (52) which is fixed on the second ring member (51), at least one flap (53) which is fixed to the rotary pin (52) and is movable with the rotary pin (52). A mixer (1) according to claim 1 or 2, comprising inner body (3) which is comprised of an air inlet channel (31) and an outlet channel (32) that are single piece, and openings (33) located at the junction of the air inlet channel (31) and the air outlet channel (32). A mixer (1) according to claim 1 or 2, comprising a mounting surface (311) of the air inlet channel (31) which extends outward from the outer body (2) and remains outside the outer body length when the inner body (3) is placed inside the outer body (2). A mixer (1) according to claim 1 or 3, comprising blade (43) which is fixed to the center part (42) at an angle according to the air intake direction. A mixer (1) or a turbulator (4) or a valve system (5) according to any one of the preceding claims, comprising a mounting elevation which is in the form of a circular protrusion for attaching the first ring member (41) and/or the second ring member (51) on the mounting surface (311). A mixer (1) or a turbulator (4) or a valve system (5) according to any one of the preceding claims, comprising at least one first lug (45) and/or second lug (55) part which is in the form of a protrusion or ridge on the first mounting elevation and/or the second mounting elevation (54), and comprises a hole thereon matching a connection protrusion (movable/push-on) located on the outer wall of the inner body (3). A mixer (1) according to claim 1 or 2, comprising at least one sealing member (6) which prevents the gas entering the inner part of the outer

15 body (2) from leaking (exiting) between the inner wall of the outer body (2) and the upper surface of the inner body (3). A mixer (1) according to claim 10, comprising sealing member (6) which is a gasket or O-ring. A mixer (1) according to claim 1 or 2 or 10, comprising at least one slot (35) which is formed with protruding surfaces on the outer surface of the inner body (3) and in which the sealing member (6) fits. A mixer (1) according to claim 1 or 2, comprising fixing assembly which is used in fixing the inner body on the outer body (2) and which comprises: at least one lock pin in the form of a protrusion which is provided on the outer surface of the inner body (3), at least one lock channel (22) which is provided at the end part of the outer body (2) in the form of an inclined channel recess on the outer body (2) and is adapted for the lock pin to be inserted therein. . A mixer (1), which is used to transfer gas and air into the combustion chamber in gas burning devices such as boilers upon mixing thereof, characterized by at least one outer body (2) which has at least one gas inlet (21) for gas transfer to its inner part and has a volume inside, at least one inner body (3) which is placed inside the outer body (2), comprises an inlet for air passage and an outlet for air-gas mixture, and at least one opening (33) for gas passage therein from the outer body (2), at least one turbulator (4) which is used for making the air more turbulent and which is comprised of

• a first ring member (41), a center part (42) preferably located on the middle part of the first ring member (41), and a plurality of fixed blades

16 (43) positioned between the center part (42) and the first ring member (41), at least one valve system (5) which enables to determine modulation rate (capacity) and to increase the minimum fan speed of the device by increasing the maximum fan speed at which the product can operate in minimum amount, and which is comprised of

• a second ring member (51) in order to be fixed to the air inlet part of the inner body (3), at least one rotary pin (52) which is fixed on the second ring member (51), at least one flap (53) which is fixed to the rotary pin (52) and is movable with the rotary pin (52).

17