GB2453382A - Cleaning away build up of biofilm in a glass cleaning apparatus - Google Patents

Abstract

A spray mechanism within a glass cleaning device has a fluid delivery manifold 48 with a nut 40 or sealing ring 42, with a number of slots or apertures, allowing a portion 54 of water or cleaning fluid in the manifold to pass through the apertures, to provide localised cleaning of an area, such as to clean away a local build-up of a biofilm.

Description

I

GLASSWASHING MACHINE

This application relates to a washing machine of the commercial cabinet type used for washing of glasses and other items in locations such as pubs, bars and restaurants.

Machines of this type often take the form of an outer cabinet and an inner wash tank such that the machine has in effect a double skin which makes it quiet and provides for good heat retention. The outer cabinet has a loading door to enable glasses and other vessels to be loaded into the wash tank which has one or more racks for supporting the vessels. A second tank for holding washing liquid is located in the outer cabinet below the level of the loading door. A spray mechanism includes a spray pump for supplying washing liquid to the wash tank and spraying the liquid over the vessels. The spray mechanism also operates to subsequently spray rinsing water from an external supply over the vessels.

Generally a wash cycle only comprises spraying washing liquid over the vessels and then rinsing the washing liquid from the vessels by spraying them with rinse water. The cycle lasts for a short period, for example two minutes, in distinction from domestic dishwashing machines in which the wash cycle lasts for at least 20 minutes and often longer.

The standard form of spray mechanism includes at least one spray arm for spraying washing water and then rinsing water on to vessels or other items held in at least one rack within the machine. The spray arm is mounted on a manifold via a manifold bearing and a seal ring is provided therebetween.

One problem which has been found to occur particularly if the machine is not regularly maintained is that a biofllm grows in the groove which receives the seal ring which results in a reduction in cleaning performance.

The present invention provides a spray mechanism comprising a manifold pipe having a bearing manifold at an end, a spray arm supported on the bearing manifold, an axle extending from the manifold bearing on which the spray arm is rotatably mounted, seal means between the manifold bearing and the spray arm, a spacer provided between the manifold bearing and the spray arm, the seal means being mounted on the spacer, and means for cleaning the seal means with wash water.

The provision of means for cleaning the seal means with wash water provides for removal of any biofllm as well as debris as part of a wash cycle.

In a particularly preferred embodiment, the spacer is formed with at least one opening for passage of wash water to the seal means. This has been found to be a very effective way of providing the cleaning means.

If, as is common, the seal means comprises a seal ring, that may be mounted around a circular portion of the spacer with the at least one opening being provided in the circular portion. Tests have shown that good results are achieved with four openings, particularly four openings in the form of slots spaced radially around the circular portion.

The manifold may be generally U-shaped and have a second manifold bearing at the second end, a second spray arm being mounted on a second manifold bearing.

A washing machine may comprise a wash tank forming a washing compartment, at least one rack supported within a washing compartment and a spray mechanism as described above. In the embodiment where there are two spray arms, these may be mounted above and below the at least one rack for spraying water onto the rack from above and below.

The invention will now be further described by way of example with reference to the accompanying drawings in which: Figure 1 is a side view, partly cut away, of a washing machine; Figure 2 is a perspective view from the bottom and rear of the washing machine of Figure 1 without the outer cabinet; Figure 3 is a perspective view of a spray mechanism of the washing machine of Figure 1; Figure 4 is a perspective view of a spray mechanism in accordance with the invention; Figure 5 is a perspective view of a spacer of the spray mechanism of Figure 4; Figure 6 is a sectional view through part of the spray mechanism of Figure 4, and Figure 7 is a further sectional view through part of the spray mechanism of Figure 4.

The washing machine 2 as shown in Figures 1 and 2 is of the commercial type used for cleaning plural glasses and other vessels.

The washing machine 2 has a steel outer cabinet 6. An opening in the outer cabinet 6 is closed by a door 8. The outer cabinet 6 is omitted from Figure 2 for clarity.

An inner wash tank 10 is mounted within the outer cabinet 6 and has a lower portion 12 forming a wash tank sump, i.e. a reservoir in which washing water is stored. Wash detergent is mixed in the reservoir which is connected via a wash pump 13 to a lower wash arm bearing manifold 14 in the wash tank 10. An upper manifold wash arm bearing manifold 15 is connected via an interconnecting manifold pipe 16.

A nnse water boiler 17 containing water and rinse agent is connected via a rinse pump 18 a rinse manifold pipe 19 and thence to the lower wash arm bearing manifold 14 and the upper wash arm bearing manifold 15.

The machine 2 includes a spray mechanism shown in Figure 3 for spraying vessels with firstly washing liquid and then rinsing water. The spray mechanism comprises lower and upper rotating arms 22, 24 mounted in the bottom and top of the inner wash tank 10 and connected to the lower and upper wash arm bearing manifolds 14, 15.

The spray arms 22, 24 have spray nozzles 26. They are self-propelling under the pressure of liquid supplied thereto which causes them to rotate and liquid to be sprayed from the spray nozzles 26 in a generally circular pattern.

A rack 28 is slidabe into and out of the inner tank 10 along rails 30 formed by side walls of the inner tank 10. The rack 28 serves to tilt the vessels 32. The tilting of the vessels 32 ensures that all the vessels are fully covered by the spray nozzles 26 and therefore properly cleaned. This is illustrated by the arrows 34 in Figure 1 which show the direction of water sprayed from the outermost nozzle 26 of the lower spray arm.

Figure 4 shows a spray mechanism 36 in accordance with the invention. The spray mechanism 36 is suitable for use in the machine 2 illustrated in Figures 1 to 3.

Where appropriate, like reference numerals will be used for like parts.

The spray mechanism 36 comprises manifold pipes 16, 19 which extend to lower and upper bearing manifolds 14, 15. The lower and upper bearing manifolds 14, 15 serve to support lower and upper spray arms 22, 24.

The upper spray arm 24 is mounted on an axle 38. A spacer 40 in the form of a separating nut is positioned between the upper spray arm 24 and the upper bearing manifold 15. A seal ring 42 is mounted on spacer 40.

The separating nut 40 is formed with four openings in the form of slots 44 spaced radially around the spacer 40 in a groove 46 provided for receipt of the seal ring 42.

During the washing cycle, some of the wash water flows through the slots 44 and around the seal ring 42 as shown by the arrows in Figure 6. This is also illustrated in Figure 7 which shows a section through the lower wash arm 22 and part of the lower wash arm bearing manifold 14. Wash water is circulated through the wash manifold 16 to wash arms 22 and 24 by the pump 30. Approximately 60% of the water flows to the lower wash arm 22 and 40% to the upper wash arm 24.

As shown in Figure 7, the wash water flows vertically up the lower wash arm bearing 48. The majority of the wash water flows into wash channels 50 in the wash arm 22 as illustrated by arrows 52. The water then flows through the nozzles 26 in the wash arm 22 resulting in a circular spray pattern. A full quantity of the wash water flows through the slots 44 in the separating nut 40 as illustrated by arrows 54.

Figure 7 also includes arrows 56 illustrating the rinse water flow and part of the tank 10.

The flow of wash water through the slots 44 in the separating nut 40 has been found to be effective to flush debris including biofilm away. When testing with raspberry pips, a notoriously difficult substance, the four slots 44 were found to result in the raspberry pips being washed away from the seal ring 42.

Claims (8)

1. A spray mechanism for use in a washing machine for washing drinking vessels and/or cutlery and/or crockery, the spray mechanism comprising a manifold pipe having a bearing manifold at an end, a spray arm supported on the bearing manifold, an axle extending from the manifold bearing on which the spray arm is rotatably mounted, seal means between the manifold bearing and the spray arm, a spacer provided between the manifold bearing and the spray arm, the seal means being mounted on the spacer, and means for cleaning the seal means with wash water.

2. A spray mechanism as claimed in claim I wherein the spacer is formed with at least one opening for passage of wash water to the seal means.

3. A spray mechanism as claimed in claim 2 wherein the seal means comprises a seal ring mounted around a circular portion of the spacer, the at least one opening being provided in the circular portion.

4. A spray mechanism as claimed in either claim 2 or claim 3 wherein there are four openings.

5. A spray mechanism as claimed in claim 4 as dependent on claim 3 wherein the four openings are slots spaced radially around the circular portion.

6. A spray mechanism as claimed in any preceding claim wherein the manifold pipe is generally U-shaped and has a second manifold bearing at the second end, a second spray arm being mounted on the second manifold bearing.

7. A washing machine comprising a wash tank forming a washing compartment, at least one rack supported within the washing compartment and a spray mechanism as claimed in any preceding claim.

8. A washing machine comprising a wash tank forming a washing compartment, at least one rack supported within the washing compartment and a spray mechanism as claimed in claim 6, the spray arms being mounted above and below the at least one rack for spraying water onto the rack.