NZ588949A

NZ588949A - A water heater with a heat exchanger where the compressor axis is inclined to the water tank axis

Info

Publication number: NZ588949A
Application number: NZ58894910A
Authority: NZ
Inventors: Mickael Edet; Christian Merlet
Original assignee: Atlantic Industrie Sas
Priority date: 2009-11-02
Filing date: 2010-11-01
Publication date: 2012-03-30
Also published as: EP2317239A2; FR2952170A1; FR2952170B1; EP2317239A3; AU2010235962A1

Abstract

A thermodynamic water heater (10) made easier to transport is disclosed. The heater has a tank (12) and compressor (18). The axis of the compressor (B) is inclined to the axis of the main water tank (A). In this position the housing of the compressor forms a storage area for oil, to lubricate the motor of the rotary compressor, from which the oil will not escape. This position allows easier transport of the water heater. A shipping container containing such a water heater is also disclosed.

Description

Received at IPONZ 9 February 2012 NEW ZEALAND PATENTS ACT, 1953 No: Date: COMPLETE SPECIFICATION THERMODYNAMIC WATER HEATER We, ATLANTIC INDUSTRIE, a French company of Rue Monge Zone Industrielle Nord, 85000 La Roche-Sur-Yon, France, do hereby declare the invention for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: Received at IPONZ 9 February 2012 2 THERMODYNAMIC WATER HEATER The present invention relates to a water heater. More particularly, the invention relates to a thermodynamic water heater.

A thermodynamic water heater is a heater adapted to heat the water that it contains, at least partially with thermal energy contained in a flow of air. Conventionally, the air flow is a stream of air in an apartment or a flow of air extracted from the apartment. This air flow can also be created by a fan.

A thermodynamic water heater mainly comprises a tank designed to contain water to be heated and a thermodynamic circuit to recover thermal energy from a flow of air with a view to heating the water in the tank.

To do this, the flow of air passes through an evaporator of the thermodynamic circuit. While passing through the evaporator, the airflow loses heat to the benefit of a refrigerant or heat transfer fluid in the thermodynamic circuit.

The refrigerant is made to circulate in the thermodynamic circuit by a compressor. The compressor also increases the pressure and temperature of the refrigerant.

The refrigerant reaches a condenser where the refrigerant transfers its thermal energy to the water in the tank. Simultaneously, the refrigerant condenses.

The condensed refrigerant reaches an expansion valve where its pressure is reduced. The refrigerant then arrives, once again, at the evaporator.

It is known to transport thermodynamic water heaters vertically, to avoid lubricating oil for the compressor entering the thermodynamic circuit in which the refrigerant circulates.

However, this vertical transport of water heaters poses many problems. Firstly, thermodynamic water heaters are generally large in size, notably some two meters high. Consequently they are not able to enter upright into the majority of vehicles used by installers. Additionally, installers have to carry a water heater vertically right up until final installation - vertically - of the water heater. This transport of the water heater in the upright position is also complex especially when going up or down stairs or through a door.

The aim of at least preferred embodiments of the present invention is to provide a water heater that does not have the drawbacks mentioned above. The invention aims in particular to provide a water heater that can be transported in a position different to the sole vertical position.

Received at IPONZ 9 February 2012 3 To this end, a first aspect of the present invention provides a water heater comprising: - a tank adapted to contain water to be heated, the tank extending along a main axis, - a heat exchange circuit between a flow of air and water to be heated, the heat exchange circuit comprising a rotary compressor adapted to circulate a refrigerant in the heat exchange circuit, the axis of the rotary compressor being inclined relative to the main axis of the tank.

According to preferred embodiments, the invention includes one or more of the following characteristics: - the axis of the rotary compressor is inclined at an angle of between 5 and 90°, preferably between 5 and 85 °, relative to the main tank axis; - the rotary compressor has a cylinder shape and has an outlet formed on a top 15 wall thereof; - the outlet is formed as a stub tube, the stub tube extending along an axis substantially parallel to the axis of the rotary compressor; - the rotary compressor has an inlet for refrigerant, arranged on a top surface of the rotary compressor; - the refrigerant inlet is formed on the same top surface of the rotary compressor as the refrigerant outlet; - the compressor is attached to the tank via a base plate, the base plate being attached to the top of the tank; - the base plate has rigidifying ribs; - the base plate comprises mounting holes for the compressor on the base plate, the mounting holes being formed at the rigidifying ribs; - the water heater has a locating mark identifying the position of the outlet of the compressor; - the outlet for refrigerant is arranged at a height of the rotary compressor 30 greater than 50% of the overall height of the compressor and preferably between 75% and 95%.

A second aspect of the present invention provides an assembly comprising a water heater as described above in any of its combinations, and a shipping container for the water heater in which the water heater is secured, the shipping container 35 including members forming a cradle for receiving the water heater.

Preferably, the shipping container includes a locating mark identifying the position for the outlet of the compressor.

Received at IPONZ 9 February 2012 4 Other features and advantages of the invention will appear on reading the following description of a preferred embodiment of the invention given by way of example and with reference to the accompanying drawing.

Figure 1 shows an example of a thermodynamic water heater in a service 5 position.

Figure 2 shows a detail of the thermodynamic water heater of Figure 1.

Figure 3 shows a partial cutaway view of the compressor of the thermodynamic water heater of Figure 1.

Figure 4 shows a water heater of Figure 1 in a transport position. 10 Figure 5 shows a mounting base plate for the compressor on the water heater of Figure 1.

Figure 6 shows a water heater of Figure 1 in a shipping container in its transport position.

As shown in Figures 1 and 2, a thermodynamic water heater 10 principally 15 comprises a tank 12 adapted to contain water to be heated and a thermodynamic circuit 14 for heat exchange between a flow of air and water to be heated.

The tank 12 extends along a main axis A. Conventionally, the main axis is positioned vertically when a water heater is installed to limit the water heater's footprint.

In the present case, the tank is substantially cylindrical. The main axis corresponds to a straight line which is the generating line for the tank surface.

Specifically, the tank has a circular cross-section. The main axis corresponds to the centerline or axis of symmetry of the tank 12.

The thermodynamic circuit 14 is partially shown in Figure 2. This 25 thermodynamic circuit comprises: - an evaporator 16, through which a flow of air passes, in which the flow of air loses its heat to the benefit of a refrigerant or coolant circulating in the thermodynamic circuit; - a compressor 18 for circulating the refrigerant in the thermodynamic circuit, 30 the compressor being also able to increase the pressure and temperature of the refrigerant; - a condenser (not shown in the figures), in which the refrigerant loses heat to the benefit of the water in the tank 12; - an expansion valve 20 where the pressure of the refrigerant is reduced.

To ensure a flow of air through the evaporator, it can be provided with a fan.

In addition, to ensure good heat exchange between refrigerant and water to be heated, the condenser can be made in the form of a metal tube wrapped around the C:\NrPortbl\WellingtonVJLV\2872556_l.DOC Received at IPONZ 9 February 2012 tank 12. To ensure even better heat transfer, the tube has a flattened face which is in contact with the tank 12.

Moreover, the compressor 18 is attached to the tank 12 through a base plate 22, which will be described later. The base plate 22 is adapted to distribute the burden of the weight of the compressor over a larger surface of the top face 12a of tank 12. This avoids concentrating pressure resulting from the weight of the compressor acting on the top of the tank. To do this, the base plate 22 extends substantially over the entire surface of the top face 12a of tank 12.

In the present case, the compressor 18 is a rotary compressor. In other words, the compressor includes a compression piston driven with a rotary movement about the axis B of the compressor. This type of compressor is more efficient than conventional piston compressors, that is to say a compressor where the piston performs a reciprocating motion. By more efficient, we mean that a rotary compressor is more energy efficient than a conventional piston compressor.

This rotary compressor is partially shown in Figure 3.

As can be seen in this figure, the compressor 18 includes a housing 24. In the present case, the housing 24 has a substantially cylindrical shape about an axis B.

Inside the casing 24, an electric motor 26 drives a rotary piston in rotation about the axis B of the compressor. The housing 24 defines a pressure chamber in which there is found the refrigerant at high pressure after compression, and the lubricating oil for the compressor. Because of the density of the compressed refrigerant and lubricating oil, the refrigerant occupies the upper part of the pressure chamber while the oil remains at the bottom of the pressure chamber, as shown in the drawing by the boundary line 28 showing the oil level. This is the reason why, in known thermodynamic water heaters, the compressor is oriented so that the compressor shaft is parallel to the main axis of the tank, the compressor outlet being arranged at the top of the compressor. The pipes forming the outlet conventionally extend substantially parallel to the main axis of the tank.

In the present case, the compressor 18 is mounted on the tank so that the axis B of the compressor 18, about which the rotary piston rotates, is inclined relative to the main axis A of the tank. Preferably, the axis B of the compressor is inclined at an angle of between 5 and 90 °, more preferably between 5 and 85 ° relative to the main axis A of the tank 12.

An angle of 90 ° ensures that when a water heater is tilted so that the main axis of the tank is substantially horizontal, then the axis of the compressor is substantially perpendicular.

C:\NrPortbl\Wellington\JLV\2872556_l.DOC Received at IPONZ 9 February 2012 6 However, a maximum angle of inclination of 85 ° is preferred to ensure that the compressor oil does not drain either, once the water heater is installed.

An angle of 45 ° can also be considered advantageous. Indeed, this angle constitutes the best compromise due to the fact that both in the position of use as well 5 as in the transport position, the inclination of the axis of the compressor is then equal to 45 ° with respect to the vertical.

In all cases, when the compressor shaft is inclined relative to the main axis of the tank, then there does exist a position of the water heater where the main axis of the tank A is substantially horizontal. In this position also, the housing 24 forms a storage 10 area for oil for lubrication of the motor of the rotary compressor from which the oil will not escape. This position allows easier transport of the water heater.

The compressor 18 further includes a refrigerant inlet 30 in direct fluid communication with the compression chamber of the compressor. Admission occurs at a top surface of the compressor, substantially normal to the axis B of the 15 compressor, as opposed to the substantially cylindrical lateral surface of the compressor.

The compressor also includes an outlet 32 for high pressure delivery, for discharging the refrigerant at high pressure, compressed by the rotary piston, to the outside of the pressure chamber defined by the casing. In the present case, the outlet 20 32 is provided in the form of a stub tube. This stub tube extends along an axis C substantially parallel to the axis B of the compressor.

The outlet 32 serves to evacuate the refrigerant from inside the casing 24 and pass it to the condenser.

The refrigerant outlet 32 is located on a top surface of the compressor 18. 25 Preferably, the fluid inlet 30 and outlet 32 are formed on the same top surface of the compressor 18 in order to limit the space occupied of the compressor 18 and water heater 10. This measure also ensures that in the transport position of the water heater, oil is not discharged from inside the water heater through the inlet 30.

In the present case, the refrigerant input and outlet are provided in the form of 30 stub tubes which extend perpendicularly to the surface they are exiting from. These pipes are oriented in a direction C, D, which in the present case is substantially parallel to the axis B of the compressor 18. This direction C, D is consequently inclined relative to the main axis A of the tank by an angle preferably comprised between 5 and 85 °.

In addition, the outlet 32 is advantageously provided in the top half of the compressor 18, and further, preferably, the height of the outlet 32 is between 75% and C:\NrPortbl\Wellington\JLV\2872556_l.DOC Received at IPONZ 9 February 2012 7 95% of the overall height of the compressor 18, this being the height measured parallel to the main axis A of the tank.

Moreover, it was found that the base plate 22 for mounting the compressor 18 on tank 12 is weakened when the compressor 18 is attached to the tank 12 in such a 5 way that its axis B is inclined with respect to the axis of the tank 12.

To remedy this weakening, it is proposed to provide, as shown in Figure 5, rigidifying ribs 34 on the base plate 22. In particular, provision is made, in order to consolidate the base plate in the area where the compressor is secured onto it,- to provide the holes 36 for mounting the compressor on the base plate at the rigidifying 10 ribs 34. Holes 38 are adapted to secure the base plate onto the top surface 12a of tank 12. These holes 38 are also provided on the rigidifying ribs 34.

It was found that a particularly fragile area of the base plate 22 is located in the region of the attachment 39 corresponding to the attachment of the compressor in line with the highest point of the compressor. By highest point, we mean the point of the 15 compressor that is farthest away from the top surface 12a of the water heater. Therefore, there are provided, in the region of this mounting hole, that is to say at a distance from this mounting hole 39 less than 25 cm, preferably less than 15 cm, and more preferably less than 5 cm, rigidifying cross ribs that provide particularly high local strength.

The water heater 10 also has a locating mark to allow the installer to know which way the water heater may be tilted. Indeed, if the water heater is not tilted so that the outlet 32 is facing up during transport, there is a risk of oil escaping from inside the compressor housing and passing into the thermodynamic circuit.

This locating mark may for example take the form of a marking on the tank 25 oriented in a direction opposite to the direction of orientation of the outlet 32.

Moreover, to transport the water heater, the heater is secured inside a shipping container 40. The shipping container includes in the present case two pallets 42, 44 connected by cross members 46. One face of the shipping container can include members 48 for receiving the water heater, secured to the cross members 46. These 30 strengthening members 48 may be slightly curved to form a cradle adapted to receive the water heater 10 and to stop it moving when the complete thermodynamic water heater assembly, received inside the shipping container, is positioned so that the main axis A of tank 12 is substantially horizontal.

The shipping container 40 may also include a locating mark 50 to allow handlers 35 to determine which way the water heater must be tilted to prevent lubricating oil from escaping from the compressor into the hydraulic system via outlet 32. In other words, C:\NrPortbl\Wellington\JLV\2872556_I.DOC Received at IPONZ 9 February 2012 8 the locating mark allows it to be determined which way the assembly can be tilted to prevent the escape of lubricating oil from the compressor into the refrigerant circuit.

Clearly, the present invention is not limited to the examples and embodiment described and illustrated, but may be the object of numerous variations accessible to those skilled in the art.

The term 'comprising' as used in this specification and claims means 'consisting at least in part of. When interpreting statements in this specification and claims which include the term 'comprising', other features besides the features prefaced by this term in each statement can also be present. Related terms such as 'comprise' and 'comprised' are to be interpreted in similar manner.

Received at IPONZ 9 February 2012 9

Claims

1. A water heater comprising: 5 - a tank adapted to contain water to be heated, the tank extending along a main axis, - a heat exchange circuit between a flow of air and water to be heated, the heat exchange circuit comprising a rotary compressor adapted to circulate a refrigerant in the heat exchange circuit, 10 the axis of the rotary compressor being inclined relative to the main axis of the tank.

2. The water heater according to claim 1, wherein the axis of the rotary compressor is inclined at an angle of between 5 and 90 0 relative to the main tank axis. 15

3. The water heater according to claim 2, wherein the axis of the rotary compressor is inclined at an angle of between 5 and 85 0 relative to the main tank axis.

4. The water heater according to any one of claims 1 to 3, wherein the rotary compressor has a cylinder shape and has an outlet formed on a top wall thereof. 20

5. The water heater according to claim 4, wherein the outlet is formed as a stub tube, the stub tube extending along an axis substantially parallel to the axis of the rotary compressor. 25

6. The water heater according to claim 5, wherein the rotary compressor has an inlet for refrigerant, arranged on a top surface of the rotary compressor.

7. The water heater according to claim 6, wherein the refrigerant inlet is formed on the same top surface of the rotary compressor as the refrigerant outlet. 30

8. The water heater according to any one of claims 4 to 7, having a locating mark identifying the position of the outlet of the compressor.

9. The water heater according to any one of claims 4 to 8, wherein the 35 outlet for refrigerant is arranged at a height of the rotary compressor greater than 50% of the overall height of the compressor. Received at IPONZ 9 February 2012 10

10. The water heater according to claim 9, wherein the outlet for refrigerant is arranged at a height of the rotary compressor between 75% and 95% of the overall height of the compressor. 5

11. The water heater according to any one of the preceding claims, wherein the compressor is attached to the tank via a base plate, the base plate being attached to the top of the tank.

12. The water heater according to claim 11, wherein the base plate has 10 rigidifying ribs.

13. The water heater according to claim 12, wherein the base plate comprises mounting holes for the compressor on the base plate, the mounting holes being formed at the rigidifying ribs.

14. An assembly comprising a water heater according to any preceding claim and a shipping container for the water heater in which the water heater is secured, the shipping container including members forming a cradle for receiving the water heater.

15. The assembly according to claim 14 wherein the shipping container includes a locating mark identifying the position for the outlet of the compressor.

16. The water heater according to claim 1, substantially as herein described 25 with reference to any embodiment disclosed.

17. A water heater substantially as herein described with reference to any embodiment shown in the accompanying drawings. 30

18. The assembly according to claim 14, substantially as herein described with reference to any embodiment disclosed. 15 20 35

19. An assembly comprising a water heater, the assembly substantially as herein described with reference to any embodiment shown in the accompanying drawings.