Electrical household appliance having a vessel for generating pressurised steam

Abstract

The invention relates to an electrical household appliance (2) having a steam generating base (1) and a steam distribution circuit, which appliance comprises an ironing and / or smoothing tool (2) connected to the base (1) by a steam duct (31), the base (1) comprising a tank (10), a vessel (12) for generating pressurised steam, and a supply circuit comprising a pump (14) supplying the vessel with pressurised water from the water contained in the tank (10), the supply circuit having, downstream of the pump (14), a bypass circuit (17), which bypass circuit diverts a portion of the water from the pump (14) to an open space at atmospheric pressure in order to make it easier to prime the pump (12), which appliance is characterised in that the bypass circuit (17) opens directly into the steam distribution circuit.

Description

Title of the invention: Household appliance comprising a tank for the generation of pressurized steam. technical field

[0001] The present invention relates to the field of household appliances comprising a tank for the generation of pressurized steam and a supply circuit configured to supply water to the tank from water contained in a reservoir. State of the art

[0002] Document EP 821 096 describes an ironing appliance comprising a steam-generating base and a steam distribution circuit including an iron connected to the base by a conduit. The base includes a reservoir, a tank for generating pressurized steam, and a supply circuit including a pump configured to supply water to the tank from the reservoir. In this appliance, the supply circuit includes, downstream of the pump, a bypass circuit configured to return some of the water from the pump to the reservoir to facilitate priming the pump when starting the appliance, either during the first use of the appliance or when the reservoir has been completely emptied beforehand, and also to vent any air bubbles present in the pump back to the reservoir.

[0003] Indeed, in the absence of such a bypass circuit opening freely into a space open to atmospheric pressure, air bubbles cannot be easily evacuated from the pump, the tank being an enclosed space into which any air bubbles present in the pump cannot easily escape.

[0004] However, such a bypass circuit has the disadvantage of being costly to implement and often unsightly because it is visible through the transparent wall of the tank.

[0005] Furthermore, such a bypass circuit to the reservoir presents usually has a relatively long length, so that it contains a large volume of water. However, when the ironing machine is switched off, the pressure in the tank decreases (due to the tank cooling down), and causes a suction effect in the bypass circuit so that the water contained in the bypass circuit is drawn into the tank.

[0006] Therefore, it is important to minimize the amount of water drawn into the tank to prevent it from containing too much water when the ironing and / or steaming appliance is next started, which would lengthen the heating time of the tank.

[0007] Furthermore, an untimely overfilling of the tank also disrupts the estimation of the amount of water contained in the tank, and therefore impairs the operation of the ironing and / or steaming appliance. Summary of the invention

[0008] The present invention aims to remedy all or part of these drawbacks.

[0009] The technical problem underlying the invention consists in particular of providing a household appliance, and in particular an ironing and / or steaming appliance, whose manufacturing costs are reduced compared to prior art appliances, while limiting the amount of water drawn into the tank when the appliance is stopped.

[0010] To this end, the invention relates to a household appliance comprising a steam-generating base and a steam distribution circuit including an ironing and / or steaming tool connected to the base by a steam duct. The base comprises a reservoir, a tank for generating pressurized steam, and a supply circuit including a pump supplying pressurized water to the tank from water contained in the reservoir. The supply circuit includes, downstream of the pump, a main supply circuit that fluidly connects the pump to the tank and a bypass circuit diverting a portion of the water from the pump to an open space at atmospheric pressure, characterized in that the bypass circuit opens directly into the steam distribution circuit.

[0011] The device may also have one or more of the following characteristics, taken alone or in combination.

[0012] According to an advantageous feature of the invention, the bypass circuit is configured to send said portion of water from the pump directly into the steam conduit.

[0013] According to an advantageous feature of the invention, the steam conduit comprises a first end connected to the tank and a second end connected to the ironing and / or steaming tool, the bypass circuit opening into the steam conduit in the vicinity of the first end connected to the tank.

[0014] According to an advantageous feature of the invention, the bypass circuit continuously draws said portion of the water from the pump when the pump is running.

[0015] According to an advantageous feature of the invention, the bypass circuit allows the free flow of said portion of the water from the pump to the steam distribution circuit. According to another advantageous feature of the invention, the water flow rate drawn through the bypass circuit when the pump is operating is less than the water flow rate sent through the main supply circuit.

[0016] According to an advantageous feature of the invention, the water flow passing through the bypass circuit when the pump is operating corresponds to at least 5% of the pump flow rate and is preferably on the order of 10% of the pump flow rate.

[0017] According to an advantageous feature of the invention, the bypass circuit allows an air flow rate of between 80 and 420 liters / hour when the pressure differential between the pump outlet and the bypass circuit is equal to 1 bar.

[0018] According to an advantageous feature of the invention, the main supply circuit includes a non-return valve.

[0019] According to an advantageous feature of the invention, the device includes a valve disposed at the outlet of the pump which performs the bifurcation between the main supply circuit and the bypass circuit, the valve having an inlet port connected to the outlet of the pump, a main outlet port constituting the starting point of the main supply circuit and a secondary outlet port constituting the starting point of the bypass circuit.

[0020] According to an advantageous feature of the invention, the bypass circuit includes a valve having a leakage flow rate that allows a continuous flow of air and / or water to pass through the bypass circuit.

[0021] According to an advantageous feature of the invention, the valve is sized so that its leakage rate when the valve is in the closed position allows less than 20% of the pump's water flow to pass through the bypass circuit. Preferably, the valve in the closed position allows 10% of the water flow from the pump to pass through the bypass circuit, with 90% of the pump's flow being sent to the tank.

[0022] According to an advantageous feature of the invention, the valve occupies an open position when the pump is stopped and a closed position when the pump is running, the flow rate of air and / or water that can pass through the valve being greater when the valve is in the open position than when the valve is in the closed position.

[0023] According to an advantageous feature of the invention, the pressure at which the bypass circuit valve closes is lower than the pressure at which the check valve opens.

[0024] According to an advantageous feature of the invention, the bypass circuit includes an expansion vessel.

[0025] According to an advantageous feature of the invention, said ironing / steaming tool is an iron. Brief description of the figures

[0026] The aims, aspects, and advantages of the present invention will be better understood from the following description of a particular embodiment of the invention, presented by way of non-limiting example, with reference to the accompanying drawings in which:

[0027] Figure 1 is a perspective view of an ironing and / or steaming device according to the present invention;

[0028] Figure 2 is a schematic view of the ironing and / or steaming device in Figure 1;

[0029] Figure 3 is a cross-sectional view of the valve located at the outlet of the pump equipping the device in Figure 1;

[0030] Figure 4 is a detailed view of the cross-sectional view of Figure 3;

[0031] Figure 5 is an exploded perspective view of the valve in Figure 3.

[0032] Only the elements necessary for understanding the invention have been shown. To facilitate reading the drawings, the same elements bear the same reference numbers from one figure to another.

[0033] Figures 1 and 2 represent a household appliance comprising a steam-generating base 1 and a steam distribution circuit including an ironing and / or steaming tool 2 which is connected to the base 1 by a cord 3. Advantageously, the ironing and / or steaming tool is an iron 2 having an ironing sole 20 which is provided with at least one steam outlet 21 and which is intended to come into contact with a garment to be ironed and / or steamed.

[0034] As is known, the iron 2 comprises a heating element 23 through which the steam from the base 1 circulates before being emitted through the vents 21. This heating element 23 includes a resistor heating element 24 which allows both the heating element 23 to be brought to a temperature above 150°C and the ironing sole 20 to be heated to around a set temperature of around 145°C.

[0035] The base 1 includes a reservoir 10 with a filling orifice 11 and includes a tank 12 for the generation of pressurized steam, equipped with regulated heating means 12A to heat the tank 12 so as to produce steam under a pressure greater than 4 bars, and for example in the order of 5 to 6 bars.

[0036] The tank 12 includes a steam outlet 30 which is connected to the ironing and / or steaming tool 2 by a steam duct 31 integrated into the cord 3. Preferably, the steam outlet 30 is equipped with a solenoid valve 32, and the ironing and / or steaming tool 2 has a control button 22 configured to open the solenoid valve 3 when the control button 22 is pressed by a user. The control button 22 may, for example, be located under a handle of the ironing and / or steaming tool 2.

[0037] The base 3 further includes a supply circuit configured to supply water to the tank 12 from water contained in the reservoir 10. The supply circuit includes in particular a pump 14 having an inlet port 15, and an inlet conduit 16 which fluidly connects the inlet port 15 of the pump 14 to a suction port 13 which is provided in a lower part of the reservoir 10.

[0038] The supply circuit further includes, at the outlet of the pump 14, a main supply circuit which fluidly connects the pump 14 to the tank 12, and which is therefore configured to supply water to the tank 12 and a bypass circuit 17 configured to continuously return part of the water from the pump 14 to the steam line 31 when the pump 14 is operating.

[0039] Preferably, the bifurcation between the main supply circuit and the bypass circuit 17 occurs at a self-priming valve 19, shown separately in Figure 3, which comprises a body including an inlet port 19A directly connected to the outlet of the pump 14 and a main outlet port 19B connected to a water supply line 18 which fluidly connects the valve 19 to the tank 12.

[0040] This main outlet port 19B is equipped with a non-return valve 190 brought back into a closed position, illustrated in figure 3, by a return spring 190A.

[0041] The return spring 190A is sized so that the non-return valve 190 opens, at the latest, when the pressure differential between the outlet of the pump 14 and the tank 12 reaches 0.9 bar in order to allow the water from the pump 14 to be sent into the tank 12. This non-return valve 190 is also advantageously sized to ensure perfect sealing and prevent the return of water from the tank 12 to the pump 14 when the pressure differential between the tank 12 and the outlet of the pump 14 is greater than 40 mb.

[0042] The valve 19 also has a secondary outlet 19C which constitutes the inlet of the bypass circuit 17 and which opens into the steam conduit 31 downstream of the solenoid valve 32, preferably in the vicinity of the latter, into a part of the steam distribution circuit of the appliance which communicates directly with the outside air through the orifices 21 of the iron 2. Preferably, the bypass circuit 17 opens into the steam conduit less than 5 cm from the solenoid valve 32 and advantageously less than 2 cm from the solenoid valve 32.

[0043] Such a bypass circuit 17 allows both the evacuation of air contained in the pump 14 and the venting of the tank 12 when a vacuum is generated inside it. Preferably, the bypass circuit 17 is arranged in the base 1 so that its length is reduced as much as possible in order to minimize the volume of water that can be stored in it. For example, the bypass circuit is sized so that the volume of water that can be stored inside it is less than 30 ml and preferably less than 20 ml.

[0044] Preferably, the secondary outlet port 19C is equipped of a movable valve 191 in translation in a bore of the valve body 19, the valve 191 being able to occupy an open position, illustrated in figure 3, in which it is brought back by a return spring 193 away from a core 192 having a central opening 192A.

[0045] In this open position, the bore receiving the valve 191 is sized to allow a significant airflow through the valve 191 and the central opening 192A. To this end, the valve 191 has a diameter smaller than the diameter of the bore in which it is inserted and features notches 191A at its end, which bear against the body of the valve 19 (visible in Figures 4 and 5). These notches allow air to circulate along the periphery of the valve 191. For example, this airflow exceeds 500 liters / hour when the pressure differential between the tank 12 and the bypass circuit 17 is equal to 1 bar.

[0046] The valve 191 is in the open position when the pressure upstream of the valve 191 is low, particularly when the pump 14 is not running. This open position of the valve 191 allows communication between the area of ​​the valve 19 located upstream of the check valve and the outside air via the bypass duct 17, the steam duct 31, and the orifices 21 of the ironing sole 20.

[0047] Thus, the opening of the valve 191 allows for an air vent which prevents a significant vacuum from being generated at the outlet of the pump 14 when the vacuum created in the tank 12 during its cooling causes the non-return valve 190 to open. This prevents water from the reservoir 10 from being drawn through the pump 14 and then into the tank 12 during the cooling of the tank 12.

[0048] The return spring 193 is sized so that the valve 191 moves to a closed position when the pressure upstream of the valve 191 reaches a threshold value that is lower than the pressure at which the check valve 190 opens. Thus, the return spring 193 is sized so that the valve 191 closes before the pressure at the outlet of the pump 14 reaches the opening pressure of the check valve 190.

[0049] As an example, the return spring 193 of the valve 191 is sized so that the valve 191 closes when the pressure upstream of the valve 191 is greater than a pressure threshold between 0.5 and 0.8 bars.

[0050] In this closed position, not illustrated in the figures, the end of the valve 191 comes into contact with the core 192 and closes the central opening 192A.

[0051] Preferably, the end of the valve 191 bearing against the core 192 has a groove 191 A, visible in Figure 5, which allows the establishment of a permanent leakage flow through the valve 191 even when the latter occupies the closed position.

[0052] This leakage flow rate is advantageously sized to allow an air flow rate of between 80 and 420 liters / hour to pass through when the pressure differential between the outlet of pump 14 and the pressure in the bypass circuit 17 is equal to 1 bar.

[0053] Such an air leakage rate from the valve 191 makes it possible to facilitate the priming of the pump 14 when starting the ironing and / or steaming appliance 2, either on the first use of the ironing and / or steaming appliance 2 or when the reservoir 10 has been previously completely emptied, by allowing the evacuation of air bubbles through the bypass circuit 17.

[0054] Furthermore, due to the presence of leakage flow through bypass circuit 17, some of the water pumped by pump 14 is sent directly to bypass circuit 17 and then into steam conduit 31. Thus, each time the control button 22 is activated, the pressurized steam exiting tank 12 pushes the water present in steam conduit 31 to send it into the heating element 23.

[0055] With the heating element 23 maintained at a temperature above 150°C by the heating element 24, most of the water droplets carried by the steam are then vaporized before reaching the steam outlet orifices 21.

[0056] Such vaporization of the volume of water injected into the steam conduit 31 during the operation of the pump 14 has the advantage of generating an additional steam flow which adds to the steam flow produced by the tank 12, which makes it possible to increase the steam flow at the outlet of the orifices 21 in the seconds following the pressing of the control button 22 and thus maximize the ironing performance of the device.

[0057] Preferably, the bypass circuit 17 and the valve 191 are sized so that the flow of water passing through the bypass circuit 17 corresponds to approximately 10% of the flow of the pump 14 under normal operating conditions, i.e. without the presence of air bubbles in the latter, with 90% of the flow of the pump 14 remaining sent into the tank 12.

[0058] When the ironing and / or steaming appliance 2 is switched off, the drop in pressure in the tank 12, due to its cooling, creates a suction effect in the bypass circuit 17. As a result, the water in the bypass circuit 17 is drawn into the tank 12 through the valve 191, which is then in the open position. However, because of the short length of the bypass circuit 17, the amount of water drawn into the bypass circuit and sent to the tank 12 is small and does not interfere with the operation of the ironing and / or steaming appliance 2.

[0059] Of course, the present invention is in no way limited to the embodiment described and illustrated, which has been given only by way of example. Modifications remain possible, particularly with regard to the composition of the various elements or by substitution of technical equivalents, without departing from the scope of protection of the invention.

[0060] Thus, in an alternative embodiment not shown, the bypass circuit may be without the check valve located at the secondary outlet of the valve. Indeed, the presence of this check valve has the advantage of allowing a greater airflow through the bypass circuit when the valve is open, i.e., when the pump is stopped, than when the pump is running. However, it may be possible to remove this check valve and size the cross-section of the bypass circuit accordingly. bypass at an average value allowing both rapid venting of the tank during its cooling and an acceptable water flow through the bypass circuit during pump operation.

[0061] Thus, in another embodiment not shown, the bypass circuit may include an expansion vessel to temporarily store the water passing through the bypass circuit. This expansion vessel will advantageously be equipped with a calibrated outlet connected to the steam line, allowing a reduced water flow to be sent through the steam line during operation of the device.

Claims

DEMANDS 1) Household appliance (2) comprising a steam-generating base (1) and a steam distribution circuit comprising an ironing and / or steaming tool (2) connected to the base (1) by a steam conduit (31), the base (1) comprising a reservoir (10), a tank (12) for the generation of pressurized steam, and a supply circuit comprising a pump (14) supplying pressurized water to the tank (12) from water contained in the reservoir (10), the supply circuit comprising, downstream of the pump (14), a main supply circuit which fluidly connects the pump (14) to the tank (12) and a bypass circuit (17) diverting a portion of the water from the pump (14) to a space open at atmospheric pressure, the bypass circuit (17) opening directly into the steam distribution circuit,characterized in that the bypass circuit (17) allows the free circulation of said portion of the water from the pump (14) to the steam distribution circuit and continuously draws said portion of the water from the pump (14) when the pump is operating. 2) Appliance (2) according to claim 1, characterized in that the bypass circuit is configured to send said portion of water from the pump (14) directly into the steam conduit (31). 3) Household appliance (2) according to claim 2, characterized in that the steam conduit (31) has a first end connected to the tank (12) and a second end connected to the ironing and / or steaming tool (2) and in that the bypass circuit (17) opens into the steam conduit (31) in the vicinity of said first end connected to the tank (12). 4) Appliance (2) household appliance according to any one of claims 1 to 3, characterized in that the main supply circuit includes a non-return valve (190). 5) Household appliance (2) according to any one of claims 1 to 4, characterized in that it comprises a valve (19) disposed at the outlet of the pump (14) which performs the bifurcation between the main supply circuit and the bypass circuit (17), said valve (19) comprising a inlet port (19A) connected to the outlet of the pump (14), a main outlet port (19B) forming the starting point of the main supply circuit and a secondary outlet port (19C) forming the starting point of the bypass circuit (17). 6) Household appliance (2) according to any one of claims 1 to 5, characterized in that the bypass circuit (17) includes a valve (191) having a leakage flow rate allowing a continuous flow of air and / or water to pass through the bypass circuit (17). 7) Household appliance (2) according to claim 6, characterized in that the valve (191) is in an open position when the pump (14) is stopped and in a closed position when the pump (14) is in operation and in that the flow rate of air and / or water that can pass through the valve is greater when the valve (191) is in the open position than when the valve (191) is in the closed position. 8) Appliance (2) household appliance according to any one of claims 6 to 7, in which the main supply circuit includes a non-return valve (190), characterized in that the pressure at which the valve (191) of the bypass circuit (17) closes is lower than the pressure at which the non-return valve (190) opens. 9) Household appliance (2) according to any one of claims 1 to 8, characterized in that the bypass circuit (17) includes an expansion vessel. 10) Appliance (2) household appliance according to any one of claims 1 to 9, characterized in that said ironing / steaming tool is an iron.

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