EXPANSION ASSEMBLY AND HOT WATER TANK

Abstract

An expansion assembly for use in a hot water device, having a water container for receiving water to be heated, includes an expansion tank with a lower expansion tank half shell and an upper expansion tank half shell. The lower expansion tank half shell has a coupling portion for coupling to the water container of the hot water device. The upper expansion tank half shell is configured to be coupled to a cold water feed line. The upper expansion tank half shell and the lower expansion tank half shell are hermetically connected at circumferential edges forming the expansion tank.

Description

TECHNICAL FIELD

The present invention relates to an expansion assembly and an associated hot water tank.

BACKGROUND

Hot water tanks for domestic use have been generally known.

For example, EP 2 827 077 discloses a water container for receiving water to be heated and an inelastic expansion tank for receiving an amount of water which is provided at the tap stop in a fitting connected to the outlet, and for receiving an amount of water which corresponds to an amount of expansion when the cold water in the water container is being heated. The expansion tank is hermetically closed to an outer environment of the hot water tank and is in fluid communication with a feed line sided water jet pump such that the water jet pump allows for a negative pressure to be created in the expansion tank.

SUMMARY

Hermetic expansion tanks have several disadvantages, e.g., it is difficult to provide for safe and reliable emptying of the expansion tank. Disclosed herein and discussed in detail below are hot water tanks having improved expansion assemblies.

According to one or more embodiments, an expansion assembly for use in a hot water device is disclosed, in particular in a hot water tank for domestic use, wherein the hot water device has a water container for receiving water to be heated, wherein the expansion assembly comprises an expansion tank, the expansion tank comprises a lower expansion tank half shell and an upper expansion tank half shell, the lower expansion tank half shell has a coupling portion for coupling to the water container of the hot water tank, the upper expansion tank half shell is configured to be coupled to a cold water feed line, and the upper expansion tank half shell and the lower expansion tank half shell are connected hermetically at circumferential edges, forming the expansion tank.

The upper expansion tank half shell and the lower expansion tank half shell may each have a circumferential friction welding edge to create a vibration friction welding connection of the upper expansion tank half shell and the lower expansion tank half shell.

The expansion assembly may be embodied by the functional integration of the coupling portion with the lower expansion tank half shell to be directly mounted onto the water container or storage tank. Hence, there is no need for an additional coupling piece, making a reduction of the number of parts possible. In its simplest configuration, the expansion assembly consists of two tank half shells, which may be produced by injection molding.

In an alternative configuration of the connection of the expansion tank half shells, the invention also allows for a further simplification and reduction of the number of parts by the functional integration of the seat emptying component into the expansion tank.

For example, a seat for an emptying component, e.g., a nozzle of a water jet pump, is integrated with the lower and/or the upper expansion tank half shell, wherein the nozzle of the water jet pump is fixed between the connected expansion tank half shells.

The emptying component allows for a negative pressure to be created within the expansion tank by the water jet of the water flowing into the hot water tank, which negative pressure then results in the emptying of the contents of the expansion tank into the hot water tank.

The expansion assembly may further include an emptying component, the emptying component having a nozzle for sucking expansion water off the expansion tank.

The venturi nozzle may have a parabolically tapering cross-sectional shape. This cross-sectional shape results in a linearly narrowing cross-sectional area. Thus, the increase of the flow rate inside the venturi nozzle is achieved with a particularly low loss of pressure.

The nozzle may be comprised of a different material than the material of the expansion tank, e.g., brass and/or bronze.

Brass and bronze may have an increased cavitation resistance.

Alternatively, the nozzle may be formed integrally with, and integrated into, the upper expansion tank half shell or the lower expansion tank half shell. In other words, the nozzle is then appropriately formed onto the tank half shell.

The upper expansion tank half shell and the lower expansion tank half shell may be embodied as easily demoldable plastics parts. Here, easily deformable means that the number of undercuts, and the complexity of the parts, are as low as possible.

In one or more embodiments, an opening between the emptying component and the expansion tank is sealed by a sealing unit which, may include a ball resting on a sealing element when the expansion tank is empty such that a negative pressure within the expansion tank is prevented.

In addition to the negative pressure, the introduction of air from the expansion tank into the storage tank is avoided. The sealing unit may have a ball and a vertical guide for guiding the ball onto the sealing element and away from the same, respectively.

In one or more embodiments, the expansion assembly further comprises a venting component, wherein the venting component is arranged at the upper expansion tank half shell and allows for air to be exchanged between expansion tank and atmosphere.

Thereby, a damaging negative pressure within the expansion tank can be prevented.

The venting component may have a blocking element, e.g., a swelling disk, wherein the blocking element is configured to prevent water from leaking out of the expansion tank via the venting component.

The blocking element may also be a further check valve such as a ball valve.

In case of failure, i.e., when water from the venting component is leaking out of the hot water tank, the blocking element can block the water leakage. This does impede the drip protection function, yet the dripping fitting is also signaling the user that the hot water tank is not working optimally. Thus, the user is able to detect the case of failure quickly.

In another aspect, an expansion assembly for use in a hot water device, in particular in a hot water tank for domestic use, is suggested, wherein the hot water device has a water container for receiving water to be heated, wherein the expansion assembly comprises an expansion tank and a venting component, wherein the venting component allows for air to be exchanged between expansion tank and atmosphere. The venting component has a blocking element, e.g., a swelling disk, wherein the blocking element is configured to prevent water from leaking out of the expansion tank via the venting component.

No matter how the tank is implemented, the venting component offers the advantages explained in the above embodiments in combination with the expansion tank formed by two expansion tank half shells.

In another aspect, a hot water tank, such as for domestic use, may comprise a storage tank, a cold water feed line for connection to a water supply network, a hot water outlet for providing hot water at a fitting connectable thereto, and an expansion assembly according to the invention.

The hot water tank according to the invention may be combined with all of the embodiments of the expansion assembly described above while offering the same advantages.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 schematically shows an exemplary hot water tank,

FIG. 2 schematically shows the exemplary hot water tank without a housing for illustrative purposes,

FIG. 3 schematically shows the exemplary hot water tank of FIG. 2 in cross-sectional view,

FIG. 4 schematically shows an exemplary hot water tank in detailed view,

FIG. 5 schematically shows an exemplary hot water tank in sectional view,

FIG. 6 schematically shows an exemplary hot water tank in sectional view,

FIG. 7 schematically shows an exemplary hot water tank in sectional view,

FIG. 8 schematically shows an exemplary hot water tank in sectional view,

FIG. 9 schematically shows an exemplary hot water tank in exploded view,

FIG. 10 schematically shows an exemplary hot water tank in exploded view,

FIG. 11 schematically shows an exemplary hot water tank in sectional view,

FIG. 12 schematically shows an exemplary hot water tank in sectional view, and

FIG. 13 schematically shows an exemplary hot water tank in sectional view.

DETAILED DESCRIPTION

FIG. 1 shows a hot water tank 1 in perspective view. The storage tank is arranged within a housing composed of two housing half shells 2, 3 and is enclosed by a thermal insulation. In the storage tank, there is drinking water which is usually heated to a desired temperature by an electric heating element to be provided at a tap as hot water.

At the front side, an operating element 4 is arranged which serves to adjust the temperature of the water in the storage tank.

At its top side, the hot water tank 1 has a cold water connection 6 and a hot water connection 8. Cold water is introduced into the storage tank via the cold water connection 6 and, via the hot water connection 8, the heated water flows to the tap.

The hot water tank 1 is usually not pressurized during operation, i.e., the pressure within the storage tank is simply atmospheric pressure and not a line pressure usual for a water line. This means that a tapping process is introduced by opening a valve or the like provided in the pipe section connected to the cold water connection 6. Due to a then positive pressure at the cold water connection 6, the inflowing cold water pushes the heated water out of the hot water connection 8.

Further, a venting assembly 80 is arranged at the top side. The venting assembly 80 is in fluid communication with an expansion assembly 70 which will be described in more detail with reference to the following figures. The venting assembly 80 allows for permanent negative pressure to be prevented inside the storage tank, and, in particular, in an expansion tank connected thereto, which might damage or destroy the hot water tank 1. Moreover, the venting group 80 is adapted to prevent leakage of liquids, i.e., water, from within the storage tank, as will be described in more detail in the following as well.

FIG. 2 shows the exemplary hot water tank 1 without insulation and housing half shells 2, 3 in schematic view (compare FIG. 1). The expansion assembly 70 is shown at a top side of the proper storage tank 10. In particular, it comprises an expansion tank composed of an upper expansion tank half shell 72 and a lower expansion tank half shell 74.

Preferably, the lower half shells of the expansion tank are connected by vibration friction welding. To this end, the upper expansion tank half shell 72 and the lower expansion tank half shell 74 have circumferential friction welding edges 73, 75. The friction welding edges 73, 75 are configured to be accessed via an appropriate machine. Vibration friction welding provides for a particularly cost effective and reliable, permanent connection between the two half shells. It is also possible to connect second half shells differently.

FIG. 3 shows the exemplary hot water tank 1 of FIGS. 1 and 2 in schematic cross-sectional view so that a heating element 12 arranged inside the storage tank 10 as well as a temperature sensor 16 are visible.

The heating element 12 embodied as electric heating element with a plurality of coils is only exemplary, other variants for heating the water within the storage tank 10 are also conceivable. The heating element 12 is electrically connected to a power supply via connections 13 and 14 formed on top of, and outside of, the storage tank.

The temperature sensor 16 exemplarily embodied as integral temperature sensor is likewise connected to a control electronics via a connection 17.

For the sake of simplicity, the control electronics are not shown in any of the figures, with the configuration necessary for controlling and/or regulating a hot water tank 1 being known to the person skilled in the art.

As shown, a cold water pipe 20 in fluid communication with the cold water inlet 6 has its opening 22 in the lower region of the storage tank 10. Thus, when a tap at a fitting (not shown) is being operated, cold water flows into the bottom region of the storage tank 10, is heated by the heating element 12 and exits the storage tank 10 via an opening 32 of the hot water pipe 30 arranged in the upper region of the storage tank.

FIG. 4 shows the exemplary expansion assembly 70 of FIG. 3 in schematic enlarged view. The cold water feed line 6 and the venting assembly are connected to the expansion assembly 70, while the hot water pipe 30 to the hot water connection 8 bypasses the expansion assembly 70 in a recess. Thus, an undesirable heat transfer from the hot water pipe 30 to the inside of the expansion tank can be prevented.

A connection portion 76 of the lower expansion tank half shell 74 can also be seen. This connection portion 76 may be formed integrally with the lower expansion tank half shell 74 and is provided for connection to a corresponding connection portion 18 (compare FIG. 12) of the storage tank 10. The cold water pipe 20 is mounted to the connection portion 18 inside the storage tank.

In the following FIGS. 5 to 7, sections along planes A-A (FIG. 5), B-B (FIG. 6) and C-C (FIG. 7) are shown so that the interior components of the expansion assembly 70 can be seen.

Cover caps 42, 44, 46 are provided at the top side of the housing of the hot water tank for covering purposes. Further, a plurality of clips 48a-48d and gaskets 50a-50i are provided for mounting and sealing purposes. The gaskets may be O-ring gaskets.

Different pipe sections 62, 30 and 82 have flanges 63, 33, 83 and 84 to provide for a safe attachment of the further components of the pipe sections 62, 30 and 82 in longitudinal direction.

A sieve 64 is arranged in the cold water connection 6 to prevent contaminations included in the water such as limestone fragments from entering into the storage tank 10.

The cold water connection 6 is coupled to the pipe section 62 via a coupling 66. Before the cold water enters into the storage tank 10 via the cold water pipe 20, it flows through an emptying component 90 which is configured to suck the contents off the expansion tank if any expansion water is present therein.

To this end, a venturi nozzle 92 is provided which results in a cross-sectional tapering to increase flow rate. The venturi nozzle 92 may be made of a metallic material, e.g., copper, and may be clamped between the upper expansion tank half shell 72 and the lower expansion tank half shell 74 in a seat 76 provided therefor. Thus, the particular ingenious configuration of the expansion tank allows for the functional integration of the emptying component.

While the venturi nozzle 92 is configured as separate metal part in this embodiment, the cross-sectional tapering may also be integrated directly with the expansion tank half shell, such as the upper expansion tank half shell 72, with no undercuts or the like making its demolding difficult.

After having exited the venturi nozzle 92, the cross-section becomes larger again before the water enters into the storage tank 10.

When water is flowing in, the venturi nozzle 92 provides for sucking of water off the expansion tank via an opening 100, which is particularly well shown in FIG. 7.

The opening 100 connects the venturi nozzle 92 to a sealing portion 98 on which a ball 96 rests sealingly when all of the water has been sucked off the expansion tank. The ball 96 has a small density so that it floats when water is flowing in and does not rest on the sealing portion 98 any longer. Thus, the water in the connection can again be sucked off the expansion tank via the venturi nozzle 92. A guiding element 94 which is open towards the expansion tank restricts the movement of the ball 96 to be substantially in vertical direction.

An arrangement similar to the one of the emptying component 90 is provided in the region of the venting assembly 80. Here, also a ball 86 is guided along a guiding element 95 in vertical direction, depending on a water level in the expansion tank. When a certain level has been reached, the ball 86 seals to a sealing portion 88 so that no water can exit the hot water tank 1 from the venting opening.

FIG. 8 shows a further section along plane A-A without the hot water pipe 30 and further pipes. In this section, elements 78 for introducing and fixing the clips are shown at the upper end of the upper expansion tank half shell 72.

FIGS. 9 and 10 show exploded views of the expansion assembly 70, with FIG. 10 additionally showing a cross-section along plane A-A.

In addition to section B-B shown in FIG. 6, a further section is depicted in FIG. 11 lying between section A-A and section B-B. Here, the opening 100 can be provided between the sealing portion 98 and the venturi nozzle 92.

FIG. 12 shows a perspective cross-sectional view similar to the view shown in FIG. 4 but with one section further backwards in the reference plane across the venturi nozzle 92.

Further shown are the connection of the connecting portion 76 of the lower expansion tank half shell 74 to the corresponding connecting portion 18 of the storage tank 10 as well as the connection of the hot water pipe 30 to a corresponding connecting portion 19 at the storage tank 19 which also forms the hot water connection 32.

In addition, a venting cap 81 can be seen in this view which forms one part of the venting assembly 80 and is adapted to ensure the closing of the venting opening when water is leaking. To this end, the venting cap 81 may preferably have at least one swelling disk. When the at least one swelling disk comes into contact with water, it swells such that the venting opening will be closed reliably.

Then, a user will detect the malfunction of the hot water tank 1 given a dripping fitting, e.g., since no expansion water, and also no dripping water in the fitting, can be received in the expansion tank when the swelling disk closes the venting opening.

FIG. 13 shows an exemplary schematic detailed view of the upper storage tank portion as well as the expansion assembly 70 in the cross-sectional view of FIG. 12.

LIST OF REFERENCE SIGNS

• • 1 hot water tank
  • 2, 3 housing half shell
  • 4 operating element
  • 6 cold water connection
  • 8 hot water connection
  • 10 storage tank
  • 12 heating element
  • 13, 14 connections of the heating element
  • 16 temperature sensor
  • 17 connection of the temperature sensor
  • 18, 19 connecting portion
  • 20 cold water pipe
  • 22 opening of the cold water pipe
  • 30 hot water pipe
  • 32 opening of the hot water pipe
  • 33 flange
  • 42, 44, 46 cover cap
  • 48 a,b,c,d clip
  • 50 a,b,c,d,e,f,g,h,i gasket
  • 62 pipe section
  • 63 flange
  • 64 sieve
  • 66 coupling
  • 70 expansion assembly
  • 72 upper expansion tank half shell
  • 73 circumferential friction welding edge
  • 74 lower expansion tank half shell
  • 75 circumferential friction welding edge
  • 76 seat
  • 78 elements
  • 80 venting assembly
  • 81 venting cap
  • 82 pipe section
  • 83 flange
  • 84 flange
  • 85 guiding element
  • 86 ball
  • 88 sealing portion
  • 90 emptying component
  • 92 venturi nozzle
  • 94 guiding element
  • 96 ball
  • 98 sealing portion
  • 100 opening

Claims

1. An expansion assembly for use in a hot water device having a water container for receiving water to be heated, the expansion assembly comprising: an expansion tank including a lower expansion tank half shell and an upper expansion tank half shell; whereinthe lower expansion tank half shell has a coupling portion configured to couple to the water container of the hot water device,upper expansion tank half shell is configured to be coupled to a cold water feed line, andthe upper expansion tank half shell and the lower expansion tank half shell are connected hermetically at circumferential edges, forming the expansion tank.

2. The expansion assembly according to claim 1, wherein the upper expansion tank half shell and the lower expansion tank half shell each have a circumferential friction welding edge to create a vibration friction welding connection of the upper expansion tank half shell and the lower expansion tank half shell.

3. The expansion assembly according to claim 1, wherein the lower and/or the upper expansion tank half shell include a seat for a nozzle of a water jet pump, wherein the water jet pump is formed between the connected expansion tank half shells.

4. The expansion assembly according to claim 1, further comprising an emptying component having a venturi nozzle configured to drain expansion water from the expansion tank.

5. The expansion assembly according to claim 4, wherein the nozzle has a parabolically tapering cross-sectional shape.

6. The expansion assembly according to claim 4, wherein the nozzle is comprised of a different material than the material of the expansion tank.

7. The expansion assembly according to claim 4, wherein the nozzle is formed integrally with, and integrated into, the upper expansion tank half shell, or the lower expansion tank half shell.

8. The expansion assembly according to claim 1, wherein the upper expansion tank half shell and the lower expansion tank half shell are embodied as easily demoldable plastics parts.

9. The expansion assembly according to claim 4, wherein an opening between the emptying component and the expansion tank is sealed by a sealing unit that includes a ball resting on a sealing element when the expansion tank is empty such that a negative pressure within the expansion tank is prevented.

10. The expansion assembly according to claim 9, wherein the sealing unit has a second ball and a vertical guide for guiding the second ball onto the sealing element and away from the same, respectively.

11. The expansion assembly according to claim 1 further comprising a venting component arranged at the upper expansion tank half shell and configured to allow air to be exchanged between the expansion tank and the atmosphere.

12. The expansion assembly according to claim 11, wherein the venting component has a blocking element configured to prevent water from leaking out of the expansion tank via the venting component.

13. (canceled)

14. The expansion assembly according to claim 12, wherein the blocking element is a swelling disk.

15. The expansion assembly according to claim 1 further comprising an emptying component.

16. The expansion assembly according to claim 15, wherein the lower and/or the upper expansion tank half shell include a seat for the emptying component, wherein the seat is formed between the expansion tank half shells.

17. A hot water tank comprising: a storage tank;a cold water feed line coupled to the storage tank and configured to connect to a water supply network;a hot water outlet coupled to the storage tank and configured to provide hot water at a fitting connectable thereto; andan expansion assembly including an expansion tank having a lower expansion tank half shell and an upper expansion tank half shell, wherein the lower expansion tank half shell has a coupling portion configured to couple to the water container of the hot water device, wherein the upper expansion tank half shell is configured to be coupled to a cold water feed line, and wherein the upper expansion tank half shell and the lower expansion tank half shell are connected hermetically at circumferential edges, forming the expansion tank.

18. The hot water tank according to claim 17, wherein the upper expansion tank half shell and the lower expansion tank half shell each have a circumferential friction welding edge to create a vibration friction welding connection of the upper expansion tank half shell and the lower expansion tank half shell.

19. The hot water tank according to claim 17, wherein the lower and/or the upper expansion tank half shell include a seat for a nozzle of a water jet pump, wherein the water jet pump is formed between the connected expansion tank half shells.

20. The hot water tank according to claim 17, wherein the expansion assembly further includes a venting component arranged at the upper expansion tank half shell and configured to allow air to be exchanged between the expansion tank and the atmosphere.