Flow heater

Abstract

A flow heater (1) comprising - a tube (3); - a heating component (4), in particular of the thick-film type, arranged at least partially around the tube (3); - a plastic shell (2) in which said tube (3) and said heating component (4) are arranged; wherein the plastic shell (2) comprises two half-shells (21, 22) constrained to each other by snap-fit connections (6, 6a, 6b).

Description

[0001] FLOW HEATER

[0002] Field of the invention

[0003] The present invention pertains to the field of electric heating devices for heating a liquid, in particular water.

[0004] In particular, the invention relates to a flow heater, or flow through heater (FTH), i.e. , a heater adapted to heat a liquid while it flows in a conduit, i.e., adapted to heat a flow of liquid in a conduit.

[0005] Background art

[0006] A flow heater, or flow through heater (FTH), is a type of electric heating device. A flow heater can also be referred to as an instantaneous heater, in particular an instantaneous flow heater.

[0007] A flow heater is particularly adapted to heat a flow of liquid, in particular water, i.e., is adapted to heat the liquid while it flows in a conduit, for example while it flows in a tube.

[0008] Flow heaters comprise a conduit for the liquid to be heated and one or more heating elements that generate heat, in particular by the Joule effect.

[0009] To date, the manufacturing of flow heaters requires skilled labor and often also requires specific machinery.

[0010] The manufacturing of a flow heater is also rather time consuming.

[0011] Furthermore, the operations of maintenance for the flow heaters can be complex, in particular in that the conduit and / or the heating element can be difficult to access, or even not accessible to be repaired or replaced.

[0012] Therefore, the need is felt to overcome the limits of the prior art.

[0013] In particular, the need is felt for a flow heater that can be manufactured in a simpler and quicker manner and that allows simplifying the operations of maintenance for the flow heater.

[0014] Summary of the invention

[0015] It is an object of the present invention to provide a flow heater that can be manufactured in a simpler and quicker manner as compared to the prior art.

[0016] It is also a particular object of the present invention to provide a flow heater that allows simplifying the maintenance operations of the flow heater.The present invention achieves at least one of such objects, and other objects that will be apparent in light of the present description, by means of a flow heater, in particular for a household appliance, according to claim 1, comprising

[0017] - a tube;

[0018] - a heating component, in particular of the thick-film type, arranged at least partially around the tube;

[0019] - a plastic shell in which said tube and said heating component are arranged; wherein the plastic shell comprises two half-shells constrained to each other by means of snap-fit connections.

[0020] Advantageously, a flow heater in accordance with the invention can be manufactured in a simpler and quicker manner as compared to the prior art.

[0021] In particular, some of the advantages associated with a flow heater in accordance with the invention are the speed of assembly and the simplicity of construction.

[0022] Furthermore, a flow heater according to the invention allows simplifying the operations of maintenance for the flow heater.

[0023] In particular, the assembly of the two half-shells by means of snap-fit connections allows reducing the fastening operations and avoid the use of dedicated tools or additional fastening means, shortens the closing / reopening times, and improves accessibility to the components housed between the half-shells, with positive effects on assembly and maintenance, without compromising the operation of the heater. Advantageously, the coupling between the two half-shells can be achieved by means of a single movement, in particular along a single axis, in particular by moving the two half-shells toward each other until engagement of the snap-fit connections.

[0024] Furthermore, a flow heater according to the invention can be manufactured so as to be compact and lightweight.

[0025] In particular, a snap-fit connection is obtained by elastic deformation of an element followed by engagement or latching of said element with a corresponding portion, in particular with a corresponding seat. For example, a tooth of a half-shell comprising a protrusion (or retaining element) bends elastically, and the protrusion engages a seat, e.g., a recess or groove, of the other half-shell, thus obtaining a constraint between the two half-shells without further fastening elements. The protrusion and the seat preferably have a complementary or substantiallycomplementary mutual shape.

[0026] The invention also relates to a household appliance according to claim 14.

[0027] The invention also relates to a method, according to claim 15, for manufacturing a flow heater, comprising the steps of:

[0028] a) arranging the tube provided with the heating component in a half-shell;

[0029] b) bringing the two half-shells toward each other and constraining the two half-shells to each other by means of snap-fit connections.

[0030] Further features and advantages of the invention will become more apparent in light of the detailed description of exemplary, but not exclusive, embodiments. The dependent claims describe particular embodiments of the invention.

[0031] Brief description of the figures

[0032] In the description of the invention, reference is made to the accompanying drawings, which are provided by way of non-limiting example, in which:

[0033] Figure 1 shows a perspective view of a device according to the invention;

[0034] Figure 2 shows a perspective view of the device in Figure 1 , with some parts shown in exploded view.

[0035] The same elements or components have the same reference numeral.

[0036] Description of exemplary embodiments of the invention

[0037] With reference to the Figures, exemplary embodiments of a flow heater 1 , or flow through heater, are described. The flow heater 1 is particularly suitable for being used in a household appliance, for example for preparing hot beverages. In particular, the flow heater 1 is adapted to be housed in a housing of the household appliance.

[0038] In all embodiments, the flow heater 1 comprises

[0039] - a tube 3;

[0040] - a heating component 4, preferably of the thick-film type, arranged at least partially around the tube 3, i.e. , arranged so that the heating component 4 extends at least partially around the tube 3, in particular about the longitudinal axis X of the tube 3; - a plastic shell 2 in which said tube 3 and said heating component 4 are arranged; wherein the plastic shell 2 comprises two half-shells 21 , 22, or two parts, constrained to each other by means of snap-fit connections 6, 6a, 6b.For illustrative simplification, only some of the snap-fit connections 6, 6a, 6b are indicated by a reference numeral.

[0041] In particular, the snap-fit connections 6, 6a, 6b are arranged along the periphery of the shell 2, in particular along the periphery of the two half-shells 21 , 22.

[0042] For example, the shell 2 comprises four sides, in particular two longer sides parallel to each other and two shorter sides parallel to each other, and each side is provided with at least one snap-fit connection 6, 6a, 6b, preferably at least two snap-fit connections 6, 6a, 6b.

[0043] Preferably, the snap-fit connections 6, 6a, 6b are cantilevered snap-fit connections. In particular, at least one half-shell 21 is preferably provided with cantilevered teeth 61. In particular, the teeth 61 are suitable for bending, in particular elastically, to initiate the snap-fit.

[0044] Preferably, each snap-fit connection 6, 6a, 6b comprises, in particular consists of, a tooth 61 of one half-shell 21 and a respective seat 62 of the other half-shell 22. In particular, each tooth 61 comprises a protrusion 611 and each seat 62 preferably substantially consists of a recess or groove. When they are constrained to one another, each tooth 61 is engaged with, in particular interlocked in, a respective seat 62. In particular, each protrusion 611 of the tooth 61 is engaged with, in particular interlocked in, a respective seat 62, which in particular is substantially a groove or recess. In particular, the teeth 61 have such a flexibility as to allow a snap-fit connection. In other words, each tooth 61 is adapted to bend (in particular, it elastically deforms), in particular during assembly between the two half-shells 21, 22, to obtain a snap-fit connection. In particular, the teeth 61 are cantilevered, in particular with respect to the respective half-shell. In particular, each protrusion 611 and the respective seat 62 have a complementary or substantially complementary mutual shape.

[0045] Advantageously, in order to release the half-shells 21, 22 from one another, the teeth 61 can bend to disengage them from the respective seat 62.

[0046] By way of example, one of the two half-shells 21 is provided with the teeth 61 and the other half-shell 22 is provided with a seat 62 for each tooth 62.

[0047] The shell 2 is preferably made of polyamide, in particular made of a plastic comprising or consisting of polyamide.In particular, the shell 2 is made of plastic having high heat resistance.

[0048] In particular, the tube 3 is arranged in a seat of the shell 2 for tube 3. Preferably, each half-shell 21 , 22 defines a part of said seat for tube 3.

[0049] In particular, the tube 3 and the shell 2 are integrally constrained to each other. The flow heater 1 preferably comprises two connectors, in particular hydraulic connectors 51 , 52. “Hydraulic connector” means, in particular, a connector designed to be crossed by a liquid. Each of the two hydraulic connectors 51 , 52 serves to connect the tube 3 to a respective conduit (not shown), for example defined by a preferably flexible respective tube.

[0050] Each hydraulic connector 51 , 52 is arranged in a respective seat 20a, 20b defined by the plastic shell 2 at a respective end of tube 3. Preferably, each half-shell 21, 22 forms a part of each of the two seats 20a, 20b.

[0051] In particular, the two hydraulic connectors 51 , 52 are locked in place by the plastic shell 2, in particular they are clamped by the two half-shells 21 , 22.

[0052] This aspect is particularly advantageous, as it further simplifies the assembly of the flow heater 1.

[0053] Advantageously, the shell 2 constrains the tube 3 and the hydraulic connectors 51 , 52 to one another, in particular integrally to one another.

[0054] Preferably, each hydraulic connector 51, 52 is inserted into a respective end of tube 3.

[0055] In particular, each hydraulic connector 51 , 52 comprises a tubular portion 510, 520, in particular having an inlet opening 519 for the introduction of liquid into the hydraulic connector 51 , 52, and an outlet opening 529 for the exit of liquid from the hydraulic connector 51, 52 (only one of the two openings of each hydraulic connector 51, 52 can be seen in the figures). Preferably, an end stretch (defining one of the two openings) of the tubular portion 510, 520 extends outside of the shell 2.

[0056] By way of non-limiting example, each hydraulic connector 51, 52 preferably comprises two flanges 511, 512, 521, 522 extending from the tubular portion 510, 520. The shell 2 is preferably arranged between the two flanges 511 , 512, 521 , 522, in particular so that one of the two flanges 511 , 521 is outside the shell 2, and the other of the two flanges 512, 522 is inside the shell 2.Preferably, each hydraulic connector 51, 52 is arranged between two respective snap-fit connections 6a, 6b. This feature enables improved locking in place of the hydraulic connectors 51 , 52.

[0057] Preferably, the separation plane between the two half-shells 21, 22 is parallel to the longitudinal axis X of tube 3 or contains the longitudinal axis X of tube 3.

[0058] In particular, the longitudinal axis X of tube 3 is the axis about which the wall of the tube 3 extends.

[0059] Preferably, the two half-shells 21 , 22 are constrained together exclusively by said snap-fit connections 6, 6a, 6b. Alternatively, in a variant not shown, the two halfshells 21, 22 can be constrained to each other by said snap-fit connections 6, 6a, 6b and by a screw (not shown), preferably a single screw.

[0060] Preferably, at least one of the two half-shells 21 , 22 has at least one opening 210 at tube 3. Said at least one opening 210 allows positioning a thermostat or a temperature sensor, for example to detect the temperature of tube 3 or heating component 4.

[0061] The tube 3 is preferably rectilinear.

[0062] The tube 3 is preferably made of metal, preferably of steel or aluminum alloy or aluminum, or a ceramic material.

[0063] In particular, tube 3 consists of a cylindrical wall, which extends about said longitudinal axis X of tube 3.

[0064] Preferably, the tube 3 has an inner diameter between 10 and 30 mm.

[0065] Preferably, inside the tube 3 there are no means, e.g., a turbulator, adapted to alter the flow of liquid passing through the tube 3, in particular adapted to increase the turbulence of the liquid.

[0066] In particular, the tube 3 is provided with the heating component 4 or in other words the heating component 4 is fastened to the tube 3.

[0067] The heating component 4, or heating device, is adapted to generate heat and transmit the generated heat to the tube 3, which in turn transmits heat to the liquid passing therethrough.

[0068] In particular, the heating component 4 extends at least partially about said longitudinal axis X of tube 3.

[0069] The heating element 4 is preferably of the thick-film type.The heating component 4 preferably comprises an electrically insulating support 41 , or electrically insulating layer, to which at least one electrically conductive track 42 is constrained, in particular made of metal, adapted to generate heat, in particular by the Joule effect.

[0070] In particular, the heating component 4 is fastened onto the outer surface of the tube 3. The electrically insulating support 41 is preferably in contact with the tube 3.

[0071] In particular, in the preferred instance in which the heating component 4 is of the thick-film type, the heating component 4 can be deposited on the tube 3, for example, in particular so as to extend at least partially around the tube 3.

[0072] The electrically insulating support 41 preferably has a thickness between 0.008 and 0.2 mm, preferably between 0.03 and 0.12 mm (in particular, the thickness is much smaller than the width and length of the electrically insulating support 41 ). The invention also relates to a household appliance comprising a flow heater 1. The household appliance can be, for example, a machine for preparing hot beverages, such as coffee. Preferably, the flow heater 1 is arranged in a housing of the household appliance, said housing of the household appliance being, in particular, distinct from the shell 2 of the flow heater 1.

[0073] The invention also relates to a method for manufacturing a flow heater 1 comprising the steps of:

[0074] a) arranging the tube 3, provided with the heating component 4, in a half-shell 21 ; b) bringing the two half-shells 21, 22 toward each other, and constraining the two half-shells 21 , 22 to each other by means of the snap-fit connections 6, 6a, 6b.

[0075] Preferably, each snap-fit connection 6, 6a, 6b comprises a tooth 61 of one halfshell 21 and a respective seat 62 of the other half-shell 22; and during step b), bringing the two half-shells 21, 22 toward each other causes the teeth 61 to bend and then each tooth 61 to engage a respective seat 62, whereby the half-shells 21 , 22 are constrained to each other.

Claims

1. CLAIMS1. A flow heater (1 ), in particular for a household appliance, comprising- a tube (3);- a heating component (4), in particular of the thick-film type, arranged at least partially around the tube (3);- a plastic shell (2) in which said tube (3) and said heating component (4) are arranged;wherein the plastic shell (2) comprises two half-shells (21, 22) constrained to each other by snap-fit connections (6, 6a, 6b).

2. The flow heater (1 ) according to claim 1 , wherein said snap-fit connections (6, 6a, 6b) are cantilevered snap-fit connections.

3. The flow heater (1) according to claim 1 or 2, wherein each snap-fit connection (6, 6a, 6b) comprises, in particular consists of, a tooth (61) of a half-shell (21) and a respective seat (62) of the other half-shell (22); in particular wherein each tooth (61) is adapted to bend for obtaining the snap-fit connection.

4. The flow heater (1) according to claim 3, wherein each tooth (61) comprises a protrusion (611) engaged with a respective seat (62), in particular interlocked in a respective seat (62); in particular wherein each seat (62) substantially consists of a recess or groove.

5. The flow heater (1) according to any one of the preceding claims, comprising two hydraulic connectors (51 , 52);wherein each hydraulic connector (51 , 52) is arranged in a respective seat (20a, 20b) defined by the plastic shell (2) at a respective end of the tube (3).

6. The flow heater (1) according to claim 5, wherein the two hydraulic connectors (51, 52) are locked in place by the plastic shell (2); in particular, wherein the two hydraulic connectors (51 , 52) are clamped by the two half-shells (21 , 22).

7. The flow heater (1) according to claim 5 or 6, wherein each hydraulic connector (51 , 52) is arranged between two respective snap-fit connections (6a, 6b).

8. The flow heater (1) according to any one of the preceding claims, wherein the separation plane between the two half-shells (21, 22) is parallel to the longitudinal axis (X) of the tube (3) or contains the longitudinal axis (X) of the tube (3).

9. The flow heater (1 ) according to any one of the preceding claims, wherein the two half-shells (21 , 22) are constrained to each other exclusively by said snap-fit connections (6, 6a, 6b); or wherein the two half-shells (21, 22) are constrained to each other by said snap-fit connections (6) and by a screw, preferably a single screw.

10. The flow heater (1) according to any one of the preceding claims, wherein at least one of the two half-shells (21 , 22) has at least one opening (210) at the tube (3).

11. The flow heater (1) according to any one of the preceding claims, wherein said heating component (4) comprises an electrically insulating support (41) to which at least one electrically conductive track (42) adapted to generate heat is constrained.

12. The flow heater (1) according to any one of the preceding claims, wherein said heating component (4) is fastened to the outer surface of the tube (3) and / or wherein said tube (3) is rectilinear.

13. The flow heater (1) according to any one of the preceding claims, wherein the shell (2) comprises four sides, preferably two longer sides parallel to each other and two shorter sides parallel to each other, and each side is provided with at least one snap-fit connection (6, 6a, 6b), preferably at least two snap-fit connections (6, 6a, 6b).

14. A household appliance comprising a flow heater (1) according to any one of the preceding claims.

15. A method for manufacturing a flow heater (1) according to any one of claims 1 to 13, comprising the steps of:a) arranging the tube (3) provided with the heating component (4) in a half-shell (21 ); b) bringing the two half-shells (21 , 22) toward each other and constraining the two half-shells (21 , 22) to each other by means of the snap-fit connections (6, 6a, 6b).

16. The method according to claim 15, wherein each snap-fit connection (6, 6a, 6b) comprises a tooth (61), in particular a cantilevered tooth, of a half-shell (21) and a respective seat (62) of the other half-shell (22); and during step b), bringing the two half-shells (21 , 22) toward each other causes the teeth (61) to bend and then each tooth (61) to engage a respective seat (62), whereby the half-shells (21, 22) are constrained to each other.

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