GB2298148A

GB2298148A - Coffee mill hopper

Info

Publication number: GB2298148A
Application number: GB9503433A
Authority: GB
Inventors: Kwai-Keung Siu
Original assignee: Chiaphua Industries Ltd
Current assignee: Chiaphua Industries Ltd
Priority date: 1995-02-21
Filing date: 1995-02-21
Publication date: 1996-08-28
Anticipated expiration: 2015-02-21
Also published as: AT404667B; HK1007045A1; GB2298148B; BE1010545A3; DE19606076A1; GB9503433D0; ATA32296A

Description

COFFEE MILL -I- The invention relates to coffee mills.

2298148 Conventional coffee mills have a top mounted hopper for coffee beans and beans of the coffee fall from a base of the hopper between a grinding wheel and a grinding cone, and ground coffee is delivered to a bottom removable container for use in a coffee percolator. It is not uncommon to have manually controllable adjustments for changing the separation between the grinding wheel and the cone to provide coarse or more finely ground coffee as required, and a timer which determines how many of the beans pass through the mill or how much ground coffee is produced.

Readily available coffee mills have only a single hopper which means that different types of coffee cannot be loaded at the same time separately in the hopper to allow for grinding separately ordinary coffee and decoffinated coffee or allow two types to be mixed in proportions to provide a blended coffee. Further, the coffee beans can often mass together or strick to the base of the hopper and therefore flow poorly or not at all out of the base of the hopper during use of the coffee mill.

It-is an object of the invention to overcome or at least reduce either or both of these problems.

According to the invention there is provided a cof fee mill having a hopper with two separate compartments and a common bottom outlet, a central control valve comprising a rotatable inverted cuP-shaped closure member f or the outlet having part of its side removed to allow cof fee beans f rom the compartments to selectively pass through the outlet according to the rotational position of the closure.

The outlet is preferably formed with a cap which fits snugly over the closure member and has side apertures through which coffee beans can pass to the outlet.

The closure member may be arranged to selectively allow coffee beans to pass from either each compartment or both compartments at the same time to the outlet. The closure member may be arranged to allow the beans to pass to the outlet in selectable relative proportions from each compartment.

A central lower region of the hopper is preferably slanted to direct beans downwards and away from a central axis of the closure member.

The base of the hopper may be sloped towards its centre to bias a flow of coffee beans towards the outlet.

The base may be formed with a plurality of upstanding ribs in its upper surface.

The base is preferably formed of thin resilient material so that the base inherently and significantly vibrates during operative use of the mill.

The hopper may be integrally formed of plastics material.

The coffee mill may have a container which fits to a lower side of the mill, and a short upstanding lug on the mill provided to restrain an outer bottom edge of the container from moving away from the mill unless the container is lifted over the lug.

The coffee mills may be formed with a single compartment hopper and the base of the hopper formed of thin material, and/or have a base which is sloped and ribbed.

Coffee mills according to the invention will now be described by way of example with reference to the accompanying drawings in which:- Figure 1 is a side elevation of the mill; Figure 2 is a sectional side view of a hopper control valve for the mill; Figure 3 is a sectional side view of a hopper for the mill; - 4 Figure 4 is top plan view of the hopper; and Figure 5 is a sectional side view of the mill with the hopper removed.

Referring to the drawings, in Figure 1 a bench standing housing 10 is provided with a control wheel 11 to adjust the grinding performance for the coffee and a control knob 12 to set a time of operation of the mill. A hopper 13 for coffee beans fits to the top of the housing 10 and a container 14 fits to a lower side of the mill to collect ground coffee. A closure control knob 15 fits on the top of the hopper 13.

In Figure 2, a rotatable closure comprises a shaft 16 which extends down to an inverted cup shaped closure 17.

Part, in fact about 1800, of the side of the closure 17 is removed or absent and it will be noted that the top of the closure 17 is slanted downwards. This allows the closure member to fit snugly in the hopper and form part of a bearing as will become apparent below. The knob 15 being manually accessible at the top of the hopper 13 (see Figure 1) can be turned to rotate the closure 17 to prbsent its open or removed side in any chosen direction about the axis of the shaft 16.

In Figures 3 and 4, the hopper is integrally formed of plastics material and provides two separate compartments 18 and 19 for coffee beans. A central tube 20 formed in the hopper is provided to allow the shaft 16 (Figure 2) to enter from below, after which the knob 15 is fitted during assembly and thereafter holds the closure member 17 in position. The lower end of the tube 20 is f ormed to provide a cap 21 that snugly f its over and bear against the closure 17 but allows relative rotation as required.

Part of the side of the cap 21, about 1800, is removed or absent. This enables the closure 17 to cooperate with the cap 21 so that coffee beans can flow out of the compartments 18 and/or 19 to the central common outlet 22 of the hopper 13. Thus, in one rotational position for example, beans flow only out of the compartment 18. In another position, beans flow only out of the compartment 19. In yet another rotational position of the closure member 17, beans can flow out of both compartments 18 and 19 in equal or, if preferred according to the actual position of the closure member 17, in a ratio of, say, 25% from one compartment and 75% from the other compartment. In other words, by selecting the rotational positions of the knob 15, the user may choose to grind only one kind of beans at a time or a selected blend (by volume ratio) of beans from both compartments 18 and 19.

It will be noted that the top of the cap 21 is sloped or slanted downwards to direct beans away from the central axis of the tube 20. This eliminates any horizontal ledges on which coffee beans might normal otherwise rest. It will also be noted that a base 23 of the hopper 13 is also sloped towards the centre of the hopper to bias the beans towards the outlet 22.

The base 23 is deliberately formed of relatively thin material so that the base in particular vibrates during operative use of the mill. The grinding of the beans causes unavoidable or inherent vibrations in the mill and this is transferred to the base 23. By making the base thin, the base 23 inherently takes up these vibrations more readily and serves to pass the vibrations onto the coffee beans in the compartments 18 and 19.

Resilient side clips 24 and 25 are provided to releasably attach the hopper 13 to the housing 10.

The base 23 is also formed with a plurality of upstanding ribs in an array, best seen in Figure 4. There is a tendency especially with some coffee beans for their natural oils to cause the beans to stick to the base. For this reason or in any event, the ribs significantly reduce any effects of stiction between the beans and the base 23 so that the beans flow more easily out of the compartments.

Figure 5 shows an internal layout of the mill. An electric motor 26 is geared to drive a grinding wheel 27 inside a grinding core 28, which in use is positioned below the outlet 22 (see Figure 3). An impeller 29 is provided to push ground coffee down a chute 29 into the container 14. It will be noted that a short lug 30 is inserted in the base of the mill. The lug restrains an outer bottom edge of the container 14 to prevent the container moving away from its position against a lower side of the housing 10 during use of the mill. The container 14 can be removed when required by lifting the container over the lug 30. Without the lug being present the container 14 may be caused to move away from the housing 10, usually due to the vibrations in the mill, during operation of the grinding wheel 27.

The described mill enables two different kinds of coffee to be ground separately or alternatively in a selected blend. It is also possible of course to simple use the two compartments for the same kind of coffee beans and thereby regard the two compartments as a large common container. Such a large container may be used to grind a larger quantity of coffee beans all at once or to grind the beans at short but perhaps relatively closely separated timed intervals. In such a situation the closure 17 can be simply used as an ONIOFF control and used for loading or controlling the operation of the mill.

It will be noted that in the described arrangement the base of the compartment is made relatively thin, sloped and also ribbed. Such features can be applied to coffee mill hoppers which have only a single compartment and provide individually or collectively novel features to enhance the operating performances of the mills. Thus, it is envisaged that embodiments of the invention may be provided having single compartment hoppers in which the base of the compartment is made relatively thin (to allow or encourage the base to vibrate), or in which the base is sloped and ribbed, or in which the base contains all three features and is thus this relatively thin, sloped and ribbed.

9 -

Claims

1. A coffee mill having a hopper with two separate compartments and a common bottom outlet, a central control valve comprising a rotatable inverted cup-shaped closure member for the outlet having part of its side removed to allow coffee beans from the compartments to selectively pass through the outlet according to the rotational position of the closure.

2. A coffee mill according to claim 1, in which the outlet is formed with a cap which fits snugly over the closure member and has side apertures through which coffee beans can pass to the outlet.

3. A coffee mill according to claim 1 or 2, in which the closure member is arranged to selectively allow coffee beans to pass from either each compartment or both compartments at the same time to the outlet.

4. A coffee mill according to claim 3, in which the closure member is arranged to allow the beans to pass to the outlet in selectable relative proportions from each compartment.

5._ A coffee mill according to any one of claims 1 to 4, in which a central lower region of the hopper is slanted to direct beans downwards and away from a central axis of the closure member.

6. A coffee mill according to any one of claims 1 to 5, in which a base of the hopper is sloped towards its centre to bias a flow of coffee beans towards the outlet.

7. A cof fee mill according to claim 6, in which the base is formed with a plurality of upstanding ribs in its upper surface.

8. A coffee mill according to any one of claims 1 to 7, in which the base is formed of thin resilient material so that the base inherently and significantly vibrates during operative use of the mill.

9. A coffee mill according to any one of claims 1 to 8, in which the hopper is integrally formed of plastics material.

10. A coffee mill according to any one of claims 1 to 9, having a container which f its to a lower side of the mill, including a short upstanding lug on the mill which restrains an outer bottom edge of the container moving away from the mill unless the container is lifted over the lug.

11. Coffee mills substantially as herein described with reference to the accompanying drawings.