GB2208133A - Heating water for drink-making apparatus - Google Patents

Abstract

A filter coffee machine includes a water tank (7) from which water is pumped over ground coffee in a filter holder (5). The pumped water from the tank (7) flows along a tube (14) leading from a heatable chamber (11) to the junction of two arms (16,18). A partition (20) at the junction divides the flow into two parts each of which flows along one of the two arms (16,18). One arm discharges water over the coffee while the other discharges water back into the tank (7). In this way, the temperature of the water used for infusion gradually increases and this reduces the extraction from the ground coffee with a resultant improvement in the taste of the coffee. <IMAGE>

Description

Improvements in or relating to Apparatus for Making Drinks This invention relates to apparatus for making drinks and has particular reference to apparatus for making coffee by the filter process in which hot water is passed through a bed of ground coffee beans supported upon a filter.

In many filter coffee makers intended for domestic use, water is heated in a tank and lifted by a bubble pump to a level from which it flows over the ground beans. It is found, however, that the coffee can be of a somewhat bitter taste and of a low temperature. The taste and the temperature are both considerably improved if the water is heated to a higher temperature before infusion takes place. Heating the entire volume of water in the tank to the higher temperature greatly increases the time that elapses before the coffee is ready and this is usually not acceptable in domestic filter coffee makers.

It is, therefore, an object of the present invention to provide a filter coffee maker which is able to produce coffee of a better taste and at a higher temperature without substantially increasing the time before the coffee is available.

According to the present invention, apparatus for making hot drinks comprises a water tank, a heater for heating water during passage from the tank to a water outlet and an arrangement for returning directly to the tank a proportion of the heater water.

Alternatively, the invention comprises coffee filter apparatus comprising a water tank, a holder for ground coffee beans, a heater heating water during passage from the water tank to an outlet located above the holder, and an arrangement for returning directly to the tank a proportion of the heated water.

Means may be provided for varying the proportion.

The interior of the water tank may be connected to the outlet via a riser tube and a water distribution arm.

The arrangement may comprise an additional arm for receiving water from the riser tube and means for dividing water flow from the riser tube between the distribution and additional arms. Means may be provided for varying the division of the water flow.

The distribution and additional arms may share a common connection to the riser tube.

The arrangement may include a partition located at the common connection for dividing the water flow.

The position and/or size of the partition may be variable in a manner such as to vary the division of the water flow.

The outlet may be located in the distribution arm which may also have a second outlet positioned to return a proportion of the water flowing along the arm directly to the water tank.

The size of one or both of the outlets may be variable.

The riser tube may have a hole through which water from the riser tube is returnable directly to the water tank.

The size of the hole may be variable.

By way of example only, embodiments of the invention will now be described in greater detail with reference to the accompanying drawings of which: Fig. 1 is a diagrammatic front view of one embodiment, Fig. 2 is a side view of the embodiment, Fig. 3 is a plan view of the embodiment with a top cover removed, and, Figs. 4 and 5 are respectively an underneath view and a side view on a larger scale of a component of the embodiment.

The embodiment shown in the drawings is a filter coffee machine intended for domestic use.

The machine has a base 1 with a surface 2 heatable by an electric heating element (not shown) and on which rests a jug 3 with a handle 4. The jug 3 has a lid 3A with a central opening located beneath an exit (not shown) of a holder 5 which, in use, holds a filter and ground coffee beans.

At the rear of the base 1 is an upstanding support 6 on which is mounted a water tank 7. The upper end of the tank 6 extends forwardly as at 8 over the surface 2.

The forward extension 7 accommodates the holder 5 as can be seen from Fig. 3.

In the base of the tank 5 above the support 6 is a water exit orifice 8 which communicates with a tube 9 containing a one-way valve shown as block 10 that permits water flow only in the direction from the tank 7 to small chamber 11 in the base 1 below the surface 2. The chamber 11 is heatable by an electric heater indicated at 12 and has an outlet joined to an outlet pipe 13 that is connected to the lower end of a riser tube 14 in the tank 7.

On the upper end of the tube 13 is mounted a bifurcated arm 15. One limb 16 of the arm 14 extends over the holder 5. That limb 16 has, adjacent its free end and in the undersurface thereof, an outlet 17 positioned centrally above the holder 5.

The other limb 16 of the arm 15 is so angled with respect to limb 16 that an outlet 19 in the lower surface is located above the water tank 7.

At the junction between the limbs 16 and 18 the arm has internal partition 20 (Fig. 4) which divides water flowing up the riser tube into two separate streams. One of the streams enters the limb 16 and exits via outlet 17 on to the ground coffee beans. The other stream enters limb 18 and is discharged via outlet 19 back into the water tank 7. The partition is sized and orientated to divide the water flow from the riser tube in about equal proportions between the reservoir and the ground coffee but other proportions may be used instead.

In operation, the water tank 7 is filled to an indicated level with cold water and a described amount of ground coffee beans is placed in the holder 5 over the filter. The tank 7 is then closed by a cover 21.

Heater 12 is then energised and after a short time interval hot water is pumped up the riser tube 14 into arm 15 and the limbs 16, 18. Water entering limb 16 is discharged over the ground coffee beans and after infusion enters the jug 3.

Water entering limb 18 is returned to the water tank via outlet 19 and is reheated during passage through chamber 11. In this way, the temperature of water entering limb 16 and used for infusion gradually increases and this reduces the extraction from the ground coffee and with a resultant improvement in the taste of the coffee.

At the same time, the final temperature of coffee in the jug 3 is higher than would otherwise be the case.

The time taken to fill the jug 3 is slightly increased but not materially so.

In an alternative embodiment, the position and/or size of the partition 20 is adjustable b a user, a suitable position control knob being located on the arm 15. Variation of the position of the partition will vary the proportion of water flowing on to the ground coffee beans and this will change the coffee taste, the final coffee temperature and the time taken.

lt is not essential to use a bifurcated arm. A single arm may be used having, at its free end, an outlet corresponding with outlet 17 and a second outlet at a position closer to the point of attachment of the arm to the riser tube and over the tank 7.

The size of one or both of the outlets may be adjustable by a user by means of a slide plate or other suitable control.

Yet again, the riser tube may have, at a suitable point along its length, a small hole giving direct access to the tank. Such a hole will allow a proportion of the water flow up the riser tube to be diverted back into the tank and its size may be adjustable.

Claims (14)

Claims:

1. Apparatus for making hot drinks comprising a water tank, a heater for heating water during passage from the tank to a water outlet and an arrangement for returning directly to the tank a proportion of the heater water.

2. Coffee filter apparatus comprising a water tank, a holder for ground coffee beans, a heater heating water during passage from the water tank to an outlet located above the holder, and an arrangement for returning directly to the tank a proportion of the heated water.

3. Apparatus as claimed in claim 2 in which means are provided for varying the proportion.

4. Apparatus as claimed in claim 1, 2 or 3 in which the interior of the water tank is connected to the outlet via a riser tube and a water distribution arm.

5. Apparatus as claimed in claim 4 in which the arrangement comprises an additional arm for receiving water from the riser tube and means for dividing water flow from the riser tube between the distribution and additional arms.

6. Apparatus as claimed in claim 5 in which the distribution and additional arms share a common connection to the riser tube.

7. Apparatus as claimed in claim 6 in which the arrangement includes a partition located at the common connection for dividing the water flow.

8. Apparatus as claimed in claim 6 in which the position and/or size of the partition is variable in a manner such as to vary the division of the water flow.

9. Apparatus as claimed in claim 5 in which further means are provided for varying the division of the water flow.

10. Apparatus as claimed in claim 4 in which the outlet is located in the distribution arm and in which the latter has a second outlet positioned to return a proportion of the water flowing along the arm directly to the water tank.

11. Apparatus as claimed in claim 10 in which means are provided for varying the size of one or both of the outlets.

12. Apparatus as claimed in claim 4 in which the riser tube has a hole through which water from the riser tube is returnable directly to the water tank.

13. Apparatus as claimed in claim 12 in which the size of the hole is variable.

14. Coffee filter apparatus substantially as herein described with reference to and as illustrated by the accompanying drawings.