GB2143108A

GB2143108A - Hot water dispenser

Info

Publication number: GB2143108A
Application number: GB08317848A
Authority: GB
Inventors: Cecil Hayes
Original assignee: Still & Sons Ltd W M
Current assignee: Still & Sons Ltd W M
Priority date: 1983-06-30
Filing date: 1983-06-30
Publication date: 1985-01-30
Also published as: GB2143108B; GB8317848D0; NL8402050A

Abstract

A hot water dispenser of a substantial size with a capacity of at least one litre, having a generally cylindrical water container 9, the base of the container formed as a casting 26, which includes heating elements 42 within the casting. This enables the easy descaling of the container. An inlet (107, Fig. 4) may be formed in the centre of the casting or else the centre of the casting may provide a centre boss 21 for securing an internal division 16 of the container therein. Easy dismantling of the container from the base may be provided by means of an annular seal 324 around the casting and a disconnectable attachment 320, 322 between the casting and container. <IMAGE>

Description

SPECIFICATION Hot Water Dispenser The present invention relates to hot water dispensers for dispensing a quantity of hot water for making a beverage.

In known hot water dispensers such as the well known tea urn or indeed an electric kettle, a container is provided in which an immersion heater element or kettle type heater element is located. During use when the water supply is chalky, that is when the water is "hard", the elements and area around the elements become coated with scale. The removal of scale, necessary if the appliance is to be maintained in the best condition, is best carried out in more sophisticated dispensers by maintenance staff on a regular basis. In any event the removal of scale is troublesome.

A hot water dispenser according to one aspect of the present invention comprises at least a hot water container having a capacity of at least one litre, the hot water container being formed as a generally cylindrical tank having removable lid on top and a base member formed as a casting with an electrical heating element or elements enclosed within the casting.

A hot water dispenser according to another aspect of the present invention comprises at least a hot water container having a capacity of at least one litre, the hot water container having a bottom closed by a detachable heater unit formed as a casting or moulding with an electrical heater element or elements enclosed within the casting or moulding.

Preferably the casting is made of aluminium or an alloy thereof.

An inlet into the container may be through a central portion of the casting. In another embodiment a central portion of the casting may form a boss for securing an internal member to the base of the container.

The provision of the container base with castin element or elements ensures the element or elements is or are fully protected from scale and the container can be easily cleaned without disassembly.

Three embodiments of the invention will now be described by way of example with reference to the accompanying diagrammatic drawings in which: Figure 1 shows a cross-section of a first embodiment of the invention, Figure 2 shows a cross-section of a second embodiment of the invention, Figure 3 is a circuit diagram for the electrical controls of the second embodiment shown in Figure 2, Figure 4 shows a cross-section of a third embodiment of the invention, Figure 5 is a circuit diagram for the electrical controls of the third embodiment shown in Figure 4, Figure 6 is a cross-section of the lower part of the tank of the dispenser of Figure 1, showing the base heater, Figure 7 is a cross-section of the heater of Figure 6 taken at 900 to the cross-section of Figure 6, and Figure 8 is a plan view of the heater element for the heater of Figure 7 prior to moulding into the heater.

The electrical circuit and operation of the three embodiments are fully described in copending British Patent Application No.8317847 filed on the same date as the present application the subject matter of which is incorporated herein.

In the first embodiment the heater 26 is formed as an aluminium casting with the heater element 42 cast into and enclosed by the casting.

A central boss 21 provides a steady and solid support for a threaded rod 23 to which a fly nut 1 8 can be screwed to hold down internal plate 1 6 the purpose and details of which are described in the said co-pending application. The cylindrical wall 9 of tank 8 has its foot secured by any suitable means to an annular protrusion 27 from the casting.

In the second and third embodiments the cylindrical walls of tanks 50 and 100 are similarly attached to heaters 54 and 106 in which elements 66 and 108 are respectively enclosed by the aluminium castings of the heaters. Central ducts 55 and 107 respectively formed in the castings into which are securely fixed ducts 60 and 104 respectively. Thermal safety cut-outs 70 and 11 8 are respectively attached to the heater castings to provide against overheating.

Figures 6, 7 and 8 show details of the base arrangements particularly for the first embodiment but also applicable to the second and third embodiments.

The heater element 42 is formed as shown in Figure 8 with the heater wire 300 separated by a suitable insulator 302 such as magnesium oxide from a steel casting 304. The element 42 is inserted in a mould for the heater 26 and aluminium or aluminium alloy is introduced into the mould so that the element 42 is totally enclosed by the aluminium or such like casting.

The heater connections 306 of course protrude from the moulding and suitable electrical connection tags 308 (see Fig. 7) are fixed to the connections 306. Also moulded into the moulding is a central securing bolt which protrudes from the boss 21. In the case of the second and third embodiments a central aperture for ducts 55 and 107 indicated by broken lines 31 2 is moulded into the heater to enable a water inlet to be formed in the heater base.

The heater 26 is secured to the tank base, which has a downwardly extending rim 314 formed thereon, by means of three clamping bolts 31 6 (one only shown in Fig. 6). The bolts 31 6 pass through lugs 318 formed on the base of the heater into threaded sleeves 320 attached to brackets 322 welded to the tank wall 9. In order to make a water tight seal between the rim 314 extending from wall 9 and the heater 26 a silicon rubber seal 324 is fitted into an annular groove 326 on the upper rim 328 of the heater. On tightening bolts 31 6 the rim 314 is firmly engaged with seal 324. This securing arrangement enables easy assembly and disassembly of the heater to the tank, whilst the cast-in element arrangement enables normal descaling to be carried out by wiping the unobstructed annular area 330.

Also moulded into the heater is an aperture 332 (see Fig. 7) into which is inserted the thermostat phial 22.

In Figure 6 can also be seen in detail the sealing of plate 1 6 to the interior of tank wall 9.

This is by means of a hollow silicon rubber seal ring 334 which seats between plate 1 6 and internal rim member 336 secured to the inside of wall 9.

Claims

1. A hot water dispenser comprising at least a hot water container having a capacity of at least one litre, the hot water container being formed as a generally cylindrical tank having a removabie lid on top and a base member formed as a casting with an electrical heating element or elements enclosed within the casting.

2. A dispenser as claimed in claim 1 wherein the base member is detachable from tank.

3. A dispenser as claimed in claim 1 or 2 wherein a water inlet to the container is formed through a central portion of the casting.

4. A dispenser as claimed in claim 1 or 2 wherein a central portion of the casting forms a boss for securing an interior member to the base of the container.

5. A dispenser as claimed in claim 2 wherein the casting is provided with an annular groove on the upper side of the casting receiving a seal sealing the casting to the container.

6. A dispenser as claimed in claim 5 wherein the casting is secured to the container by means of a central member secured to a central boss of the casting.

7. A dispenser as claimed in any of the preceding claims wherein the container is divided into two by a central dividing plate means having a vent into an upper portion of the container.

8. A dispenser as claimed in claim 7 wherein the dividing plate means has a duct communicating from the upper part of the container to the lower part of the lower portion of the container.

9. A dispenser substantially as described with reference to any one or more of Figures 1, 6, 7 and 8 of the accompanying drawings.

1 0. A dispenser having a base member substantially as described with reference to Figures 2 or 4 of the accompanying drawings.