GB2502811A - Food processing tool - Google Patents

Abstract

The present invention provides a tool intended as an attachment or accessory for a food processor and configured to automate the delicate operation of folding ingredients together without expelling air. The tool comprises first and second curved blades 20, 30 which depend from a casing part 40 that is rotated within a processing bowl by means of a geared arrangement that picks up rotary drive from a drive shaft 43 coupled to a driven outlet on the base of the food processor. The blades are disposed at different distances from the axis about which the casing rotates, so that the outer blade passes closer to the wall of the bowl than does the inner blade, and the food-contacting surfaces of the blades are each formed to gently lift and turn ingredients, such that the outer blade turns ingredients in towards the axis and the inner blade turns ingredients outwardly therefrom. A gearing arrangement is provided to rotate either or both of the blades relative to the casing part, thereby causing at least one of the blades to execute a planetary mixing action.

Description

FOOD PROCESSING TOOL

This invention relates to food processing, and it relates more especially to a tool attachable to an electrically driven food processor and usable for mixing ingredients in a bowl. The tool has particular application to the kind of processing that involves folding ingredients together without substantial expulsion of air from the mix. Such a tool is described and claimed in our co-pending UK patent application No. GB I 200294.4, and this invention comprises an improvement or modification of that tool.

The folding operation as used in cookery is quite difficult to carry out manually, since the ingredients must be moved in a way that takes practice to perfect and it has typically been the practice hitherto to use a large spoon to gently lift and fold ingredients together. However, over folding or under folding can result in unsatisfactory results, either with the final product not rising frilly and/or with the ingredients not being mixed together properly.

The tool described and claimed in the aforementioned patent application was devised to be used as an attachment to a food processor, wheieby the folding action could be automated and optimised; enabling users to repeatedly produce acceptable results, even if they are not experienced in the requisite manual techniques.

This invention aims to provide a further improved tool for such purposes, and accordingly provides a food processing tool comprising a casing part intended for bodily rotation about a drive axis and housing gear means z adapted to pick up rotary drive from a food processor drive shaft disposed on said axis, the casing supporting first and second dependent blade members disposed at different orientations around said axis, wherein foodcontacting surfaces of the blade members are each formed to gently lift and turn ingredients; one of the blade members being configured to turn ingredients in towards the axis and the other said blade member being configured to turn ingredients outwardly therefrom; wherein further driving means are provided for causing at least one of said blade members to rotate about a second axis offset from that of the food processor shaft.

By this means, the gentle folding action achieved by an experienced cook using spoons is simulated.

In some preferred embodiments of the invention, the second axis is disposed substantially parallel to the axis of the drive shaft.

Preferably, the said gear means comprises a first stationary sun gear, centered on said axis, and a planet gear having a first gear located and configured to pick up rotational drive from said drive shaft and a second gear arranged to mesh with and run around said sun gear.

It is also preferred that the said ftirther driving means comprises a second stationary sun gear disposed coaxially with the first, and a second planet gear centered on said second axis; the second planet gear being arranged to mesh with and run around the second sun gear as the casing part rotates bodily around the first-mentioned axis when driven by said drive shaft.

Preferably the gear means causes the tool to rotate at a speed in the range from 15 to 60 rpm, since this permits ingredients to be folded without significant expulsion of air.

In preferred embodiments, the blade members are removable from the casing part to facilitate cleaning or replacement.

It is preferred that the blade members are each formed with a compound curvature and tilt l:o simulate manual folding of ingredients using a spoon.

Preferably, when in operation, one of the blade members remain fixed relative to said casing part.

To utilise the invention, a user simply attaches the tool to a food processor, sets the operating speed of the food processor to the desired speed and runs the machine for a predetermined length of time, or for as long as required to achieve a preferred consistency.

In order that the invention may be clearly understood and readily carried into effect, one embodiment thereof will now be described, by way of example only, with reference to the accompanying drawings of which: Figure 1 is derived from the aforementioned UK patent application No, GB 1200294.4 and shows a food processor howl, in phantom outline, and a perspective view of a tool in order to convey the general nature and configuration of the tools under consideration; Figure 2 is also derived from the earlier patent application and shows the tool with the upper part of its casing removed to reveal a basic internal gearing in exploded view; and Figures 3 and 4 are overhead and isometric views respectively of a tool in accordance with one example of this invention.

Referring now to the drawings, the tool 10 comprises a pair of paddle-like blades 20 and 30 depending from a casing 40 which contains gearing including wheels 41 and 42 arranged so as to pick up the drive from a drive shaft, disposed centrally of the bowl 60 of an electrically driven food processor. The lower part of the drive shaft is shown at 43 in Figures 1 and 2, and its upper part is shown at 50 in Figure 2. The tool 10 is configured and disposed so as to slowly and bodily rotate around the shaft 43, 50.

As is well known, the drive shaft is driven in rotation from beneath the bowl 60 by means of an electric motor housed in a base casing (not shown) of the food processor, and appropriately geared. In this example, the drive shaft 43, 50 is fined over, and driven by, an in-howl drive system located in the base of the bowl and driven from an outlet of the food processor.

In some alternative embodiments, the drive shaft 43, 50 passes through an aperture in the base of the bowl 60 and runs in a central tube or chimney extending along the central axis of the bowl, It will be appreciated in this respect, however, that the precise maimer in which the drive of the food processor is picked up and conveyed to the tool 10 is of little significance to the operation of the invention.

In this example, the paddle-shaped blades 20 and 30 are formed, as shown in the drawings, with flat, open food-contacting surfaces which are gently curved and tilted towards their lower ends; the overall shape of each blade being designed to emulate the aforementioned manual folding movement when the casing 40 with its two dependent blades 20, 30 is bodily rotated o at a slow speed about the axis of the drive shaft 50 by the interaction of the gears 41 and 42 with the shaft 43, 50. Gear 42 is, in this example, kept stationary, either by location to hard (fixed) points on the lid or by other means.

As can be seen from Figures 1 and 2, the blades 20 and 30 depend from opposite ends of the casing 40 and thus they are angularly offset as regards their relative motion around the bowl. Indeed, in this example, the blades are offset by substantially 180 degrees in angle. Furthermore, the blades are disposed at different locations radially of the bowl 60. Tn this respect, blade 20, is disposed close to the upright wail of the bowl 60 and thus constitutes an outer blade; the tilt on its food-contacting surface being inwards towards the centre of the bowl. Blade 30, on the other hand, rotates closely around the centre of the bowl 60, and the tilt on its food -contacting surface is outwards, towards the side wall of the bowl 60.

The outer blade 20 is thus effective, in use, to lift ingredients in the bowl and roll them over towards the centre of the bowl 60, whereas the inner blade 30 is designed to lift ingredients and roll them over towards the outside wall of the bowl 60.

In this way, the tool 10 as a whole is designed to simulate the folding action required to fold ingredients together without knocking the air out; the profiles of the blade surfaces being designed to simulate the movement that would be achieved manually if using a spoon.

The gears 41 and 42 and their interaction with the main drive shaft 43, 50 constitute an epicychcai gearbox, built into the casing 40 of the tool 10 which, in this example, is effective to reduce the rotational speed of the blades 20 and 30 down to 15 to 60 rpm, which is slow enough to fold the 1 5 ingredients without knocking out the air.

In the configuration shown in the drawings of the aforementioned UK patent application No. GB 1200294.4, the blades 20 and 30 are stationary relative to the casing 40 in operation, although it is envisaged that they could be configured to move. In accordance with the example of the present invention now to be described, the outer blade 20 is arranged to rotate about a vertical axis 70 which is oriented parallel to that of the drive shaft 43, 50. It will be appreciated that, in other examples, the inner blade 30 could be caused to rotate instead of; or as well as, the outer blade 20. /

With particular reference now to Figures 3 and 4, the rotary movement of tool 20 about the axis 70 is conveniently achieved by modit'ing the gearing shown in Figure 2 by providing an upper, stationary gearwheel 44 coaxially with the stationary gearwheel 42, and arranging the gearwheel 44 to mesh with a mobile gearwheel 45 that is capable of turning the outer tool 20 about the axis 70.

By this means, the gearwheel 41 meshes with driving splines an the shaft 43, 50 and causes gearwheel 42 to run around the stationary gearwheel 42, as before. This causes bodily movement of the casing 40 about the axis of the central drive shaft 43, 50; carrying the tools 20 and 30 around with it.

In addition. in the arrangement of Figures 3 and 4, however, the gearwheel 45 runs around the upper stationary gearwheel 44, causing the outer tool 20 to rotate about the axis 70. it will be appreciated that alternative driving techniques could be used without departing from the scope of the invention and moreover, as already mentioned, that the inner tool 30 could be driven instead ot or as well as, the outer tool 20. It will also be appreciated that the gearing ratios will be selected to provide a desired bodily rotation rate for the casing 40 and a desired rotational rate of the tool 20 (and/or of the tool 30).

in any event, it is preferred that the blades 20 and 30 are removable from the casing 40 for cleaning and storage purposes. In this respect, it will be appreciated that the blades 20 and 30 can be coupled to the casing 40 in any convenient way to pennit ready removal, and ready and secure re-attachment. The shape of the tools 20 and 30 will clearly vary with different food processor designs and in some embodiments of the invention, particularly where one or both of the tools are driven in rotation, the tools 20, 30 may he interchangeable to achieve different processing characteristics.

in this example of the invention, the fold tool 10 is configured to rotate bodily in an anti-c1ockwise direcl:ion within the howl 60, and the outer tool 20 also rotates anti-clockwise about the axis 70.

In operation, the ingredients are moved around as the blades 20, 30 rotate within the bowl. The outer blade 20 scoops the ingredients up, rolls them over and deposits them towards the centre of the bowl 60. The inner blade 30, on the other hand, SCOO5 tile ingredients up, rolls them over and deposits them towards the outer part of the bowl 60.

As mentioned above, and as can be seen from the drawings, the fold tool to is, in this example of the invention, rotated around the bowl via an epicychc gearbox 41, 42, 44, 45 built into the casing 40.

if desired, either or both of the blades 20 and 30 and1or their supporting shanks may be made somewhat flexible, or may be made of material that can flex in use.