"FOOD MIXER CLEANING SYSTEM"

FIELD OF THE INVENTION

This invention relates to cleaning systems for industrial food mixers.

BACKGROUND

A typical food mixer, such as a dough mixer for mixing or kneading dough used in food such as bread products, biscuits or pastry, has a mixing bowl, a mixing or kneading tool that is driven to rotate within the mixing bowl, and an electric motor for driving the mixing tool. In use the dry and liquid ingredients are added to the mixing bowl and the mixer operates to mix or knead the ingredients to form dough. On completion the dough is removed from the mixing bowl.

Typically there is residual dough mixture adhered to the interior of the mixing bowl after the dough has been removed. It is necessary to clean the interior of the mixing bowl and the mixing or kneading tool before the next use. Commonly the mixing bowl is cleaned manually to hand scrape excess dough from the interior of the mixing bowl. A quantity of water is then supplied into the mixing bowl from a hose for example, the mixing bowl lid is closed and the mixer is run for up to thirty minutes. The water and dough are then tipped from the mixing bowl. During cleaning the mixer is out of operation, decreasing the production output from the mixer. Alternatively it is known for the mixer operator to scrape and then wash out the mixing bowl by hand with a hose. The water and removed dough are tipped out of the mixing bowl ready for the next batch of dough ingredients.

Both the above require the mixer operator to lean over or climb into the interior of the mixing bowl, which risks personal injury. During both of the above the area around the mixing bowl becomes wet and slippery, also creating a risk of injury to the operator. As increasingly a higher standard of cleaning is required, to minimise the risk of any allergen build-up that would otherwise pose a hazard to consumers, the time required to acceptably clean a mixing bowl is increasing. This further increases production plant downtime.

SUMMARY OF THE INVENTION It is an object of the invention to provide an improved cleaning apparatus for a food mixer or at least provide the public with the useful alternative.

In broad terms in a first aspect the invention comprises food mixer cleaning apparatus for cleaning the interior of a food mixing bowl comprising a support ring for fitting to the food mixing bowl around a rim of the food mixing bowl or within the food mixing bowl near the mouth of the

food mixing bowl, and mounting thereto at least one spray nozzle assembly for delivering cleaning fluid under pressure within the interior of the food mixing bowl.

In a second aspect the invention comprises a method of cleaning the interior of a food mixing bowl using a cleaning unit assembly comprising the steps of: removing a lid covering an opening having a rim in said food mixing bowl, inserting a bowl cleaning assembly mounted to a support ring into said opening such that said support ring abuts said rim of food mixing bowl, engaging said lid to said food mixing bowl to seal said support ring between said lid and said rim, connecting a pump to a fluid supply, initiating a desired bowl wash cycle to be undertaken by said cleaning unit assembly to pump a cleaning fluid into said food mixing bowl under pressure, removing said lid and said support ring with said bowl cleaning assembly from said food mixing bowl on completion of said bowl wash cycle, and draining said cleaning fluid from said food mixing bowl.

The invention also includes a cleaning apparatus for cleaning the interior of a vertically orientated food mixing bowl having a lid comprising: a support ring for attachment to said food mixing bowl, a hollow support frame having a first end attached to the periphery of said support ring for supporting a bowl cleaning assembly, said bowl cleaning assembly including: at least two substantially elongate hollow bodies attached at one end to said support frame each of said at least two substantially elongate hollow bodies including a cleaning head assembly rotatably engaged, a connector mounted on said support ring and interconnected to said hollow support frame, and a conduit having a first end releasably connected to said connector, a pump releasably connected to a second end of said conduit, said pump operable to provide a fluid at a pressure to said at least two substantially elongate hollow bodies via said conduit to deliver a high pressure fluid output from said cleaning head assembly to clean said food mixing bowl interior.

The term "comprising" as used in the specification means "consisting at least in part of, that is to say when interpreting statements in this invention which include that term, the features prefaced by that term in each statement, or need to be present but other features can also be present.

BRIEF DESCRIPTION OF THE DRAWINGS

A preferred form of the invention is described by way of example only and with reference to the accompanying drawings in which:

Figure 1 is a perspective view of a preferred form cleaning apparatus of the invention (herein sometimes referred to as a cleaning ring),

Figure 2 is a side view of the cleaning ring of Figure 1 fitted to the bowl of a vertical axis food mixer bowl and connected to a pump,

Figure 3 is a view of a spray nozzle assembly of the preferred embodiment,

Figure 4 is a cross-section of the support ring, and Figure 5 is a view of a mobile pumping station for connection to the cleaning ring when fitted to a mixer.

DETAILED DESCRIPTION OF PREFERRED FORM

An industrial food mixer includes a large mixing bowl in which ingredients used to form bread, biscuit, or pastry dough are placed and mixed, and having a lid. The mixer has a dough arm carrying a mixing or kneading tool (not shown) that in operation moves within the interior of the mixing bowl to mix ingredients in the mixing bowl.

Referring to Figure 1 , the preferred form cleaning apparatus includes substantially circular frame or support ring 4 which can be fitted to the rim of a mixer bowl. The support ring 4 is of a diameter to match that of the rim of the bowl of the mixer or mixers with which it is to be used.

Also, it may be oval or square or rectangular in shape alternatively to suit different mixer bowl shapes.

Extending to one side of the support ring 4 are cleaning head support brackets 9, each of which mounts a cleaning head or spray nozzle assembly 8, which will be further described. Extending across the support ring 4 is a tube or conduit 7 which supplies cleaning fluid from a coupling 12 at one side of the external periphery cleaning ring and to which a fluid supply hose 11 may be connected, to each of the two cleaning heads 8. Handles 23 may also be provided on the external periphery of the support ring 4.

In one embodiment the support ring 4 may be formed from extruded section or channel 30 as shown in cross-section in Figure 4. The lower surface 31 of the support ring may sit on top of the mixer bowl rim. When the support ring 4 is positioned on the mixing bowl rim and the mixing bowl lid is placed on top of the support ring and clamped, the support ring and spray nozzle assemblies 8 (the cleaning ring) is locked into position on the mixing bowl. The cleaning ring may optionally include quick release couplings 5 around its periphery which can engage in recesses in the external circumference of the mixing bowl below the rim of the bowl to assist in

- A - holding the cleaning ring in position. A cover 32 of a nylon, plastics or rubber material may extend over and around the support ring 4 and may cover the internal 34, external 35 and upper surfaces 33 of the support ring to provide a watertight seal between the support ring when in place and the mixing bowl and lid. Alternatively the diameter of the support ring may be slighdy less than that of the moudi of a bowl having tapered sides so that the cleaning ring is a wedge fit into die top part of the interior of the bowl.

Figure 3 shows an individual spray nozzle assembly, comprising spray nozzles 18. Cleaning water under pressure is delivered through the conduit 7 to each spray head and causes the spray nozzles 18 to rotate, as indicated by arrow E about a transverse first axis and simultaneously as indicated by arrow F about a co-axial (or parallel) axis, so that the high pressure fluid flow from die nozzles 18 generates a substantially spherical high pressure spray from the cleaning head 8 within the interior of the mixer bowl, towards the walls and underside of die lid of die mixer bowl, to dislodge dough remaining sticking to the interior of the bowl and Hd and clean the bowl and lid. Whilst it is preferable to provide four nozzles 18 as shown or more, less preferably may be provided two opposing nozzles 18 or a single nozzle. It is preferable that multiple nozzles 18 are spaced equidistandy.

In die particular form shown a pinion gear 16 is attached to a shaft 19 that is inserted into a hollow body 22. The cleaning head assembly 8 is formed by a plate 20 having a bevel gear pinion 17 arrangement integral with the bottom of the plate 20 for engagement widi the bevel gear 16. The bevelled gear and pinion arrangement 16, 17 enables the cleaning head assembly 8 to rotate in one plane to provide a first axis of rotation. Extending upwardly from the top surface of die plate 20 is a substantially hollow housing 21 having a central axis of rotation concentric witii the plate central axis of rotation. The nozzles 18 are preferably perpendicular to the hollow housing 1 and preferably located around the circumference of the hollow housing 1. Rotation is driven by the pressure of the cleaning fluid flow through the cleaning head assembly 8.

Referring to Figure 2, as stated the cleaning ring 4 is of a diameter that it can be fitted to the rim 6 of a mixing bowl 2 underneath the mixing bowl lid 3, both shown in phantom outline schematically. That is, after ingredients have been mixed within the bowl, the lid of the bowl is removed, die interior of the bowl hand scraped of large pieces of excess dough, following which the cleaning ring is then fitted onto the rim of the bowl and the Hd replaced over the cleaning ring. When the cleaning ring is to be removed from the mixing bowl, after cleaning operations, the bowl Hd is undamped and removed and the cleaning ring Hfted from the bowl. Dirty cleaning fluid may be ^" tipped from or drained from the mixing bowl. A connector on the end of hose 11 which connects to coupling 12 on the cleaning ring may be of a quick release type to enable the cleaning

πng 4 to be detached from the hose and pump making the cleaning ring easier to position on and remove from the mixing bowl.

A high pressure positive displacement cleaning fluid pump 41 may be fixed to or integral with the mixer and may be operated via a mixer control panel integral with the mixing machine. Alternatively the cleaning ring can be connected via hose 11 to a mobile pump trolley 40 shown in

Figure 5 having a pump 41 powered by a 3-phase motor on a moveable platform or pedestal 42.

Extending upwards from the trolley base 42 is a support framework 43 with integral handle 44 used by an operator indicated at 50 to push die pump trolley 40 around the bakery area between mixers. Located below the handle 44 is a control panel 46 used by the operator to set and control the pump 40 and wash cycle. Power is provided to the control panel 46 via a power supply cable that is connected to a power supply oudet integral with a mixer or alternatively connected to a power oudet.

In use, when a mixing bowl is to be cleaned, the operator moves the mobile cleaning station 40 to a position in close proximity to the mixer, removes the cleaning ring from the mobile cleaning station and locates the cleaning ring onto the rim of the mixer bowl, and then replaces the bowl lid and locks it into position and initiates the bowl wash cycle from the control panel 46. The pump 41 supplies cleaning fluid at high pressure via the hose 11 to the cleaning ring and cleaning heads 8 which rotate to deliver high impact sprays of cleaning fluid that clean the interior of the mixing bowl. Once the wash cycle has commenced the operator is free to undertake other work. More specifically, in a preferred embodiment once the dough making process has been completed and the dough has been removed from the mixing bowl the mixer operator undertakes the following steps in order to clean the interior of the mixing bowl.

^■ Unclamp and remove the mixing bowl lid from the bowl.

^■ Manually remove excessive dough pieces from the interior of the mixing bowl. ■ Tilt the mixing bowl to a half-tilt position.

^■ Remove the cleaning apparatus from the mobile cleaning station (or other storage location) and locate the support ring 4 onto the mixing bowl rim.

^■ Couple the high pressure cleaning fluid hose 11 to the connector 12 using the quick release coupling. ■ Tilt the mixing bowl to an upright position before closing and clamping the lid in position on the mixing bowl to seal the mixing bowl.

^■ Open the bowl drain (if fitted to the mixing bowl).

^■ Initiate a wash cycle, ensuring cleaning fluid is being pumped to the cleaning ring.

^■ Unclamp and remove the mixing bowl lid and tilt the mixing bowl to a half-tilt position on completion of the wash cycle.

^■ Release die hose 11 and lift die support ring 4 off the mixing bowl rim and re-store the support ring 4. ■ Tilt the mixing bowl downwards to allow the soiled cleaning fluid to be drained from the interior of the mixing bowl (if the mixing bowl does not comprise a drain).

^■ Tilt the mixing bowl to a closed position (upright position) once all of the cleaning fluid has been drained and replace the lid.

We have found that the time taken to clean a mixing bowl can be reduced from at least 30 minutes when done manually to about 2.5 minutes, for a twin cleaning head system 1 of the invention. The table below shows the results of the tests undertaken to date.

Twin Lance System

3 minutes — standard clean Bowl Clean Cycle Time

6 minutes — allergen clean

100 litres - standard clean Water Usage per Cycle

200 litres — allergen clean

The foregoing describes the invention including a preferred form thereof. Alterations and modifications as would be obvious to those skilled in the art are intended to be incorporated within the scope hereof, as defined in the accompanying claims.