GB2577329A

GB2577329A - Tank for fluid

Info

Publication number: GB2577329A
Application number: GB1815521.8A
Authority: GB
Inventors: Charles Grant Adam
Original assignee: Jaguar Land Rover Ltd
Current assignee: Jaguar Land Rover Ltd
Priority date: 2018-09-24
Filing date: 2018-09-24
Publication date: 2020-03-25
Anticipated expiration: 2038-09-24
Also published as: GB2577329B; GB201815521D0

Abstract

A tank 1 for fluid, the tank 1 having an inlet, an outlet 5, and a variable volume element 6, e.g. a bellow, disposed in the tank below the outlet. The element has a first configuration in which it is compressed by fluid in the tank (Fig. 6A). In a second configuration, when fluid is withdrawn from the tank 1, the variable volume element 6 expands to occupy a larger volume; this decreases the volume of the tank below the outlet 5 which is occupiable by fluid. Also, a variable volume element 6 for a tank 1, the element being generally planar and for securing in the tank below its outlet. The element 6 is expandable to increase in volume when a fluid is removed from the tank; and is biased to expand. Also, vehicles including such tanks 1 and elements 6. The tank may include a heating element.

Description

TANK FOR FLUID

TECHNICAL FIELD

The present disclosure relates to a tank for fluid, and particularly, but not exclusively, to a tank for a selective catalytic reduction (SCR') reagent. Aspects of the invention relate to a tank including a variable volume element, to a variable volume element suitable for inclusion within a tank for fluid, and to a vehicle including a tank having a variable volume element.

BACKGROUND

Selective catalytic reduction (1SCR) is a process for converting oxides of nitrogen contained in the exhaust gases expelled from an internal combustion engine in to diatomic nitrogen and water. In general, the process includes injecting a reductant, typically urea, into a catalyst through which the exhaust gases flow from the engine to the atmosphere. The urea is stored in liquid form in an SCR tank.

Present SCR tank arrangements include a pump having an inlet located at the bottom of the tank, with the main body of the pump being located generally below the main body of the tank. In general, the pump is gravity fed, so the volume of the tank cannot be increased below the pump inlet even if packaging space within a vehicle in which the SCR tank is installed is available to do so.

Tanks having a variable internal volume are known. Such tanks attempt to address the issue of otherwise unusable storage volume below the level of a pump inlet and utilise a surface which is biased resiliently away from a bottom surface of the tank. These arrangements require a separate biasing arrangement (such as springs) in order to bias the surface away from the base of the tank, along with a sealing arrangement to seal the space between the edges of the surface and the bottom of the tank.

Accordingly, addressing the problem of unusable storage volumes with alternative arrangements to those presently proposed is desired.

SUMMARY OF THE INVENTION

Aspects of the invention provide a tank for fluid including a variable volume element, a variable volume element for a tank, and a vehicle as claimed in the appended claims.

According to an aspect of the invention, there is provided a tank for fluid, the tank having an inlet, an outlet, and a variable volume element disposed inside the tank, below the outlet, wherein the variable volume element has a first configuration in which the variable volume element is compressed by fluid in the tank, and a second configuration in which, when fluid is withdrawn from the tank, the variable volume element expands such that it occupies a larger volume and decreases the volume of the tank below the outlet which is occupiable by the fluid.

This can provide the advantage that the variable volume element may be compressed under the weight of the fluid stored in the tank. This can increase the internal volume and therefore the capacity of the tank. As fluid is removed from the tank, the variable volume element may expand, with an upper surface of the variable volume element moving upwards toward the outlet of the tank, so that substantially all of the liquid stored in the tank may be removed from the tank via the outlet of the tank. This may ensure that substantially all of the fluid stored within the tank may be removed from the tank. In addition, the variable volume element does not require separate biasing and sealing arrangements.

Optionally, the variable volume element is biased into an uncompressed state.

This can provide the advantage that as fluid is removed from the tank, the variable volume element may expand without external influence.

Optionally, the variable volume element is in an uncompressed state when the level of fluid in the tank is at or below the outlet.

This can provide the advantage that when the fluid level in the tank is at or below the outlet, the remaining fluid may be removed from the tank.

Optionally, the variable volume element is disposed adjacent a base of the tank.

This can provide the advantage that the movement of the variable volume element is downwards when it is compressed by fluid stored within the tank, and it may increase the simplicity and efficiency of the variable volume element.

Optionally, the variable volume element is removably affixed to the base of the tank.

This can provide the advantage that the variable volume element may be replaced simply if it 35 becomes damaged.

Optionally, the variable volume element includes apertures on a lower face thereof, and the base of the tank includes corresponding projections such that the variable volume element is clipped to the base of the tank.

This can provide the advantage that the variable volume element may be secured within the tank such that it does not move within the tank, but may be removed from the tank and replaced if the variable volume element becomes damaged.

Optionally, the variable volume element includes a conduit arranged to vent the variable volume element.

This can provide the advantage that when the variable volume element is compressed, the air within the variable volume element may be vented therefrom, to enable the element to compress more easily.

Optionally, the conduit is in fluid communication with atmosphere.

This can provide the advantage that the air removed from the variable volume element does not pass into the internal volume of the tank, and therefore reduces the likelihood that fluid stored within the tank becomes drawn into the variable volume element as it expands.

Optionally, the conduit is a breather pipe, which passes through an outer wall of the tank.

This can provide the advantage that the outlet for the air from within the variable volume element is less likely to become blocked. This means that the variable volume element may compress and expand more reliably.

Optionally, the breather pipe includes a filter element at an end distal to the variable volume element.

This can provide the advantage that ingress of foreign matter into the breather pipe and the variable volume element is reduced. This means that the variable volume element may compress and expand more reliably In some examples, the tank includes a heating element for heating the fluid contained within the tank, the heating element being adjacent the base of the tank.

This can provide the advantage that if the fluid contained within the tank becomes more viscous or substantially solid at low temperature, the fluid may be heated such that it becomes liquid or substantially less viscous. This may enable the fluid to be drained from the tank more effectively.

Optionally, the heating element is between the base of the tank and the variable volume element.

This can provide the advantage that the liquid between the base of the tank and the variable volume element is heated and the heat may subsequently conduct through the fluid contained within the tank. This may enable the fluid to be drained from the tank more easily.

Optionally, the heating element is formed in a lower face of the variable volume element.

This can provide the advantage that the variable volume element and the heating element may be formed together. This may reduce the complexity of the tank arrangement, and may reduce the overall manufacturing cost thereof.

Optionally, the base of the tank includes recesses which correspond to the configuration of the heating element in the lower face of the variable volume element such that liquid stored in the tank is in contact with the heating element.

This can provide the advantage that the liquid between the base of the tank and the variable volume element is heated efficiently. This may enable the fluid to be drained from the tank more easily.

Optionally, the heating element is affixed to the lower face of the variable volume element, and the variable volume element is spaced away from the base of the tank such that liquid stored in the tank is in contact with the heating element.

Optionally, the heating element is configured to heat a liquid contained within the variable volume element.

This can provide the advantage that a liquid contained with the variable volume element may be heated so as to increase the temperature thereof. This may enable it to flow from within the variable volume element more easily.

Optionally, if the tank includes a conduit, when the variable volume element is compressed, the liquid passes into the conduit.

This can provide the advantage that as the variable volume element expands, the liquid provides a pressure head to enable the variable volume element to expand more easily.

According to another aspect of the invention, there is provided a variable volume element for a tank, the variable volume element being generally planar and configured to be secured inside the tank, below an outlet of the tank, the variable volume element being expandable so as to increase in volume when a fluid is removed from within the tank, the variable volume element being biased into an expanded state.

This can provide the advantage that the variable volume element may be placed within a tank, and be compressed under the weight of the fluid stored in the tank. This can increase the internal volume and therefore the capacity of the tank. As fluid is removed from the tank, the variable volume element may expand, with an upper surface of the variable volume element moving upwards toward the outlet of the tank, so that substantially all of the liquid stored in the tank may be removed from the tank via the outlet of the tank. This may ensure that substantially all of the fluid stored within the tank may be removed from the tank easily.

Optionally, the variable volume element is formed of two generally planar surfaces joined by a deformable side wall.

This can provide the advantage that the variable volume element may be placed within a tank easily.

Optionally, the two generally planar surfaces are shaped to include a cut-out to accommodate a fluid pumping arrangement.

This can provide the advantage that the variable volume element may be placed within a tank which has a pumping arrangement in a base thereof.

Optionally, the cut-out is at an edge of the variable volume element.

This can provide the advantage that the variable volume element may be manufactured more simply. This may reduce the cost of manufacture of the variable volume element, and it may also reduce the failure rate of the variable volume element.

This can provide the advantage that the air removed from the variable volume element may be directed away from the variable volume element. This may enable the variable volume element to be positioned more efficiently in a tank.

Optionally, the conduit is placed at an edge of the variable volume element.

This can provide the advantage that the variable volume element may be vented more simply out of a tank in which is it placed.

Optionally, the variable volume element includes a heating element.

This can provide the advantage that if a fluid contained within a tank which contains the variable volume element becomes more viscous or substantially solid at low temperature, the fluid may be heated such that it becomes liquid or substantially less viscous. This may enable the fluid to be drained from the tank more effectively.

Optionally, a lower surface of the variable volume element includes a heating element.

This can provide the advantage that the variable volume element and the heating element may be formed together. This may reduce the complexity of the variable volume element, and may reduce the overall manufacturing cost thereof.

Optionally, the heating element is affixed to a lower surface of the variable volume element.

This can provide the advantage that a liquid stored within the tank and held between the base of the tank and the variable volume element may be heated. This may enable the fluid to be drained from the tank more easily.

A further aspect of the invention provides a vehicle including a tank as described above.

This can provide the advantage that fluid stored within the tank may be removed from the tank easily.

A yet further aspect of the invention provides a tank for fluid, the tank including a variable volume element as described above.

This can provide the advantage that the variable volume element may be compressed under the weight of the fluid stored in the tank. This can increase the internal volume and therefore the capacity of the tank. As fluid is removed from the tank, the variable volume element may expand, with an upper surface of the variable volume element moving upwards toward the outlet of the tank, so that substantially all of the liquid stored in the tank may be removed from the tank via the outlet of the tank. This may ensure that substantially all of the fluid stored within the tank may be removed from the tank easily.

Another aspect of the invention provides a vehicle including a tank as described above.

This can provide the advantage that it enables the storage capacity of liquid storage within the vehicle to be increased.

Within the scope of this application it is expressly intended that the various aspects, embodiments, examples and alternatives set out in the preceding paragraphs, in the claims and/or in the following description and drawings, and in particular the individual features thereof, may be taken independently or in any combination. That is, all embodiments and/or features of any embodiment can be combined in any way and/or combination, unless such features are incompatible. The applicant reserves the right to change any originally filed claim or file any new claim accordingly, including the right to amend any originally filed claim to depend from and/or incorporate any feature of any other claim although not originally claimed in that manner.

BRIEF DESCRIPTION OF THE DRAWINGS

One or more embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings, in which: Figure 1 shows an exploded view of an exemplary tank arrangement; Figure 2 shows a top view of an exemplary tank arrangement; Figure 3 shows a side view of an exemplary tank arrangement; Figure 4 shows an end view of an exemplary tank arrangement; Figures 5A and 5B show an exemplary tank arrangement including a variable volume element in an uncompressed state; Figures 6A and 6B show an exemplary tank arrangement including a variable volume element in an uncompressed state; and Figure 7 shows an example vehicle.

DETAILED DESCRIPTION

A tank in accordance with an embodiment of the present invention is described herein with reference to the accompanying Figure 1.

With reference to Figure 1, there is illustrated a tank 1 for fluid, the tank 1 having an upper portion 2 including an inlet 3, and the tank 1 further includes a pump 5 including an inlet 8 which provides an outlet from the tank, and a variable volume element 6 disposed inside the tank 1. The variable volume element 6 of Figure 1 is generally elongate in shape and is a blow-moulded single-piece bellows arrangement. It is to be appreciated that the variable volume element 6 may take an alternative shape and may be formed using any suitable manufacturing technique.

In Figure 1, the variable volume element 6 is positioned adjacent a base 7 of the tank. The variable volume element 6 is located below the outlet of the tank 1, and below the inlet 8 of the pump 5.

The tank of Figure 1 further includes a breather pipe 9 which allows the air contained within the variable volume element 6 to be expelled out of the tank 1, and through a filter cap 10 which is positioned on the upper portion 2 of the tank 1. This breather pipe 9 may take any suitable form, and may also exit the tank 1 through any appropriate face. In some examples, the breather pipe 9 may exit through the base 7 of the tank 1, and this will be discussed in more detail later.

The tank of Figure 1 also includes a heating element 11, positioned generally between the variable volume element 6 and the base 7 of the tank 1. This will be discussed in more detail later.

Turning to Figure 2, the upper portion 2 of the tank 1 is shown. The upper portion 2 of the tank 1, filter cap 10, and the inlet 3 are all visible. The upper portion 2 of the tank 1 of Figures 1 and 2 also includes fixing arrangements 20 to enable the tank 1 to be secured in a vehicle.

Figure 3 shows a side view of the tank 1 of Figures 1 and 2, and shows the lower portion 12 which includes the base 7 of the tank 1. The pump 5 including a fluid outlet 13 can also be seen in the lower portion 12 of the tank 1.

The end of the assembled tank 1 of Figure 3 is shown in Figure 4, with the pump 5 and fluid outlet 13 thereof visible, along with the filter cap 10.

Figures 5A and 5B show a cross-sectional view of the tank 1 of Figures 3 and 4, with the variable volume element 6 in an uncompressed state. As seen in Figure 5A and 5B, the pump is located within the tank such that the inlet 8 of the pump 5 is positioned above the uppermost surface of the variable volume element 6, when the variable volume element 6 is substantially uncompressed. Further, it can be seen in Figures 5A and 5B that the variable volume element 6 is shaped so as to accommodate the pump 5, with the base 7 of the tank 1 including a portion within which the body and fluid outlet 13 of the pump 5 to be accommodated.

Fixing arrangements 14 are shown in Figure 5A, with the fixing arrangements 14 configured to secure the variable volume element 6 to the base 7 of the tank 1. The fixing arrangements 14 may be such that the variable volume element 6 is permanently affixed to the base 7 of the tank 1, or the fixing arrangements 14 may be such that the variable volume element 6 is releasably affixed to the base 7 of the tank 1 to enable convenient replacement of the variable volume element 6. Such a combination of features may facilitate ease of assembly of a tank 1 including a variable volume element 6.

Furthermore, the or each fixing arrangement 14 may provide an outlet for the breather pipe (not shown), such that the breather pipe may expel air from inside the variable volume element 6 to atmosphere.

Figures 6A and 6B show a cross-sectional view of the tank 1 of Figures 3 and 4, with the variable volume element 6 in a compressed state. The compressed variable volume element 6 increases the internal volume of the tank 1 which may be occupied by a fluid. The variable volume element 6 may be compressed by the weight of a liquid stored within the tank 1. The fixing arrangements 14 of Figure 5A are shown in Figure 6k Returning to a more general discussion, the pump 5 may be gravity-fed, with the inlet 8 of the pump 5 positioned in an upper portion of the pump 5, and the pump 5 inlet 8 may be positioned in a top surface of the pump 5. To enable fluid to be drawn into and be pumped by the pump 5, the top surface of the pump 5 must be positioned above, or connected to, the base 7 of a tank 1 for fluid. Therefore, in the case of a tank 1 without a variable volume element 6, then only the volume which is positioned above the inlet 8 of the pump 5 may be used to store any fluid which is to be withdrawn from the tank 1 by the pump 5.

In the present case, where the tank 1 includes a variable volume element 6, the inlet 8 of the pump 5 or, more generally, the outlet 5 of the tank 1, may be positioned such that it is above, or substantially aligned with, the top surface of the variable volume element 6.

If the pump is located outside of the internal volume of the tank, the outlet of the tank 1 could be an aperture in a wall of the tank which communicates the internal volume of the tank with an inlet of the pump. If the pump is located within the internal volume of the tank, the outlet of claim 1 could be an inlet of the pump (with none of the walls of the tank having an aperture providing an outlet of the tank). Particularly, the variable volume element 6, when uncompressed, may provide a top surface which is substantially in line with the outlet 5 of the tank 1. The outlet 5 of the tank 1 may, as discussed above, be the inlet 8 of a pump 5.

In the case that a pump 5 is located outside of the internal volume of the tank 1, the outlet 5 of the tank 1 may take the form of an aperture in a wall of the tank 1 which communicates the internal volume of the tank 1 with an inlet 8 of the pump 5. It is also envisaged that the outlet 5 of the tank 1 may be an inlet 8 of the pump 5.

In use, under the weight of fluid stored in the tank 1, the variable volume element 6 may become compressed. Therefore, when fluid is contained within the tank 1 at a level above the outlet 5 of the tank 1, the variable volume element 6 is compressed such that it occupies a smaller volume and increases the volume of the tank 1 occupiable by the fluid.

It follows that the variable volume element 6 may expand as the tank 1 is emptied, thereby raising the level of the fluid stored within the tank 1 so that it may be fed into the inlet 8 of the pump 5 inlet located in the base 7 of the tank 1. Further, to enable the variable volume element 6 to compress efficiently, as discussed above, the air contained therein may be vented outside the variable volume element 6. This may be achieved by way of a conduit 9 which may be the breather pipe 9 discussed above, and this conduit 9 may be in fluid communication with the interior volume of the variable volume element 6 and may vent to atmosphere.

This may allow air to flow out of the interior volume of the variable volume element 6, when the tank 1 is being filled, thereby allowing the variable volume element 6 to compress, and to allow air to flow in to the interior volume of the variable volume element 6 as the tank 1 empties, thereby allowing the variable volume element 6 to expand.

The breather pipe 9 may, as discussed above, include a filter cap 10 in order to reduce the likelihood of ingress of contaminants into the interior volume of the variable volume element 6, with the filter cap 10 provided at an end of the breather tube which is exposed to the exterior of the tank 1.

As an alternative to the breather pipe 9 discussed above, a bore may be provided through at least one of the fixing arrangements 14 as discussed above. This combination may allow fluid communication between the interior volume of the variable volume element 6 and the exterior of the tank 1, and may be mechanically simpler than the breather pipe 9.

It is envisaged that a conduit 9 such as the breather pipe 9 may pass out of the variable volume element 6 and through a wall of the tank 1 in any suitable location.

As shown in Figure 1, the tank 1 may include at least one heating element 11, such that a fluid stored in the tank 1 may be prevented from freezing, or may be defrosted.

As with Figure 1, the or each heating element 11 may be provided between the base 7 of the tank 1 and the variable volume element 6. Alternatively, the or each heating element 11 may be integrated into the underside of the variable volume element 6, and may be provided in wire or mat form.

The heating elements 11 of either type may be spaced away from the base 7 of the tank 1 (or the base 7 of the tank 1 may be shaped appropriately) such that the heating elements 11 may make contact with the fluid stored in the tank 1, to enable heat to be transferred into the fluid.

Where heating elements 11 are affixed to or formed in the underside of the variable volume element 6, the variable volume element 6 may be affixed to the base 7 of the tank 1 such that it is spaced away from the base 7 thereof, providing a gap into which fluid may enter.

As an example, heating elements 11 may be provided within grooves in the base 7 of the tank 1, and the variable volume element 6 shaped such that fluid would sit within the grooves between the heating elements 11 and the underside of the variable volume element 6.

An alternative heating arrangement may be provided within the tank 1, and such an alternative heating arrangement may provide a volume of liquid, such as water, inside the interior volume of the variable volume element 6. The volume of liquid may conduct heat from a heating element 11 located on the base of the variable volume element 6, through the variable volume element 11 and into the fluid contained within in the tank 1.

As the variable volume element 6 is compressed during filling of the tank 1, the fluid within the variable volume element 6 may be displaced through the breather pipe 9. This combination of features may present additional advantages, in that as the tank 1 empties, the pressure head provided by the liquid in the breather pipe 9 may act to expand the variable volume element 6. This reduces the demand on the variable volume element 6 to be resiliently biased.

These embodiments provide an improved tank 1 for fluid which may increase the capacity available for the storage of fluid within a vehicle. As a variable volume element 6 is provided this may enable the tank 1 to be larger, but to be accommodated around other components within the vehicle to maximize the use of space within the vehicle.

As illustrated in Figure 7, if the vehicle 1 includes a diesel engine then the vehicle 1 may include a tank 1 for storing urea used in selective catalytic reduction ('SCR') as described above. However, the vehicle 100 may include one or more tanks 1 according to embodiments of the invention, and the vehicle 100 may include one or more tanks configured to store several types of fluid.

Although reference has been made to a tank being suitable for storage of urea used for selective catalytic reduction ('SCR'), it will be appreciated that a tank according to an aspect of the present invention may also be suitable for storing any one of a number of fluids that require storage within a vehicle, such as fuel, coolant, screen wash or oil. It is advantageous to optimise the capacity of such tanks 1 so as to reduce the frequency at which they need to be refilled, whilst optimising the use of space within the vehicle 100.

Although embodiments of the present invention have been described in the preceding paragraphs with reference to various examples, it should be appreciated that modifications to the examples given can be made without departing from the scope of the invention as claimed.

For instance, in the above described examples the tank 1 for fluid is used in a vehicle. In other examples the tank 1 for fluid could be used in oil tankers, farm vehicles, lawn mowers, boats or any other suitable devices.

Systems utilising sensors to monitor the volume of fluid stored within the tank 1 may be calibrated to take account of the effective volume of the tank 1 varying with the volume of fluid contained within the tank 1, given the compression and expansion of the variable volume element 6.

It will be appreciated that various changes and modifications can be made to the described aspects and/or embodiments without departing from the scope of the present invention.

Claims

CLAIMS1. A tank for fluid, the tank having an inlet, an outlet, and a variable volume element disposed inside the tank, below the outlet, wherein the variable volume element has a first configuration in which the variable volume element is compressed by fluid in the tank, and a second configuration in which, when fluid is withdrawn from the tank, the variable volume element expands such that it occupies a larger volume and decreases the volume of the tank below the outlet which is occupiable by the fluid.
2. A tank according to claim 1, wherein the variable volume element is biased into an uncompressed state.
3. A tank according to claim 1 or claim 2, wherein the variable volume element is in an uncompressed state when the level of fluid in the tank is at or below the outlet.
4. A tank according to any one of claims 1-3, wherein the variable volume element is removably affixed to the base of the tank.
5. A tank according to claim 4 wherein the variable volume element includes apertures on a lower face thereof, and the base of the tank includes corresponding projections 14 such that the variable volume element is clipped to the base of the tank.
6. A tank according to any one of claims 1-5, wherein the variable volume element includes a conduit arranged to vent the variable volume element.
7. A tank according to claim 6, wherein the conduit is in fluid communication with atmosphere.
8. A tank according to any preceding claim including a heating element for heating the fluid contained within the tank, the heating element being adjacent the base of the tank.
9. A tank according to claim 8, wherein the heating element is between the base of the tank and the variable volume element.
10. A tank according to claim 9, wherein the heating element is formed in a lower face of the variable volume element.
11. A tank according to claim 10, wherein the base of the tank includes recesses which correspond to the configuration of the heating element in the lower face of the variable volume element such that liquid stored in the tank is in contact with the heating element.
12. A tank according to claim 8, wherein the heating element is affixed to the lower face of the variable volume element, and the variable volume element is spaced away from the base of the tank such that liquid stored in the tank is in contact with the heating element.
13. A tank according to claim 8, wherein the heating element is configured to heat a liquid contained within the variable volume element.
14. A tank according to claim 13, when dependent upon claim 6, wherein when the variable volume element is compressed, the liquid passes into the conduit.
15. A variable volume element for a tank according to any preceding claim.
16. A variable volume element for a tank, the variable volume element being generally planar and configured to be secured inside the tank, below an outlet of the tank, the variable volume element being expandable so as to increase in volume when a fluid is removed from within the tank, the variable volume element being biased into an expanded state.
17. A variable volume element according to claim 16, wherein the variable volume element is formed of two generally planar surfaces joined by a deformable side wall.
18. A variable volume element according to claim 17, wherein the two generally planar surfaces are shaped to include a cut-out to accommodate a fluid pumping arrangement.
19. A variable volume element according to any one of claims 16-18, wherein the variable volume element includes a conduit arranged to vent the variable volume element.
20. A variable volume element according to claim 19, wherein the conduit is placed at an edge of the variable volume element.
21. A variable volume element according to any one of claims 16-20, wherein the variable volume element includes a heating element.
22. A variable volume element according to claim 21, wherein the heating element is affixed to a lower surface of the variable volume element.
23. A tank for fluid, the tank including the variable volume element according to any one of claims 16-22.
24. A vehicle including a tank according to any one of claims 1-14 or claim 23.