GB2221456A

GB2221456A - Article dispensing apparatus

Info

Publication number: GB2221456A
Application number: GB8818720A
Authority: GB
Inventors: John Nicholas Reid
Original assignee: CIRCUITWARE Ltd
Current assignee: CIRCUITWARE Ltd
Priority date: 1988-08-06
Filing date: 1988-08-06
Publication date: 1990-02-07
Also published as: ZA895956B; GB8818720D0

Abstract

Apparatus for dispensing articles comprises a plurality of hooks 14 each for supporting a respective article, and means for selectively heating any individual hook, the application of heat to a hook being capable of releasing the article suspended on that hook, whereby the article may fall from the hook under its own weight. Either the hook bends under the effect of heat to release the article, or the article has a part, e.g. of plastics engaging the hook, such that the plastics weakens on heating. The articles may lie on sloping shelves 22 so as not to hit a lower hook when falling. <IMAGE>

Description

ARTICLE DISPENSING APPARATUS The present invention relates to article dispensing apparatus and is particularly suited for use in a cold environment, for example to dispense items of frozen food in an automatic vending machine.

There have been many proposals to combine a freezer compartment with a microwave oven in order to permit automatic vending of hot food, such as hamburgers. A serious problem to be overcome in the construction of such a machine is that the mechanism employed to select an item from the freezer compartment and transfer it to the oven tends itself to freeze and eventually to fail through the accumulation of frost.

The present invention therefore seeks to provide a dispensing mechanism which can work reliably, even in a frozen environment.

According to a first aspect of the present invention, there is provided a method of dispensing articles which comprises suspending the articles from individual hooks and applying heat to a hook in order to release a selected article to be dispensed, the application of heat serving to release the container from the hook.

In the preferred embodiment of the invention, the articles to be dispensed are packaged in containers each having a portion from which the container can be suspended, at least the portion of the container from which it can be suspended being made of a material capable of being softened or melted by the application of heat, and the heat applied to the hooks serves to weaken the container so that it may fall off the hook under its own weight.

As an alternative, the hook may be formed in such a manner that it changes shape on the application of heat to permit the article to fall under its own weight. In this case, each hook may include a bimetallic portion which bends on the application of heat to retract the hook from the container.

According to a second aspect of the invention, there is provided apparatus for dispensing articles which comprises a plurality of hooks each for supporting a respective article, and means for selectively heating any individual hook, the application of heat to a hook being capable of releasing the article suspended on that hook, whereby the article may fall from the hook under its own weight.

Because each article is suspended, the force required for its transportation is its own weight and no transfer mechanism with moving components is needed. Once a container is released, it merely falls into a chute and travels along the chute out of the dispensing apparatus.

The only point at which freezing can possibly create a problem is in the releasing of the article from the hook and, since in the invention the release is effected by applying heat to the hook, this problem is avoided.

Preferably, each article is packaged in a container having a portion from which it can be suspended, at least the latter portion of each container being made of a material capable of being softened or melted by the application of heat.

In this embodiment, the portion of the container from which it is suspended is softened by the application of heat and the dispensing is carried out without the use of any moving parts in the apparatus.

The invention can thus be seen to provide an elegant solution to the dispensing of articles, which even works reliably for items of food stored in a freezer. However, the invention is not restricted in its use to a frozen environment because the inherent reliability and simplicity of manufacture of the apparatus makes it suitable for applications where freezing is not a source of problems.

The extent to which the hook needs to be heated to enable the article to be released may vary but it is possible to verify that an article has been released by monitoring the passage of the article along the dispensing chute. The hook may be heated for as long as necessary for the article to be released or for a length of time which is predetermined to be sufficient to release an article under most operating conditions.

In the latter case, if no article is detected on the chute at the end of the heating of the hook, it is possible either to make a further attempt at heating the same hook, or to retrieve a similar article from another hook.

The hooks are conveniently arranged on vertical trays which may be withdrawn from the dispensing apparatus for refilling. On the trays, the hooks may be disposed in rows and columns so that the heating elements associated with the hooks may be connected in a matrix, thereby reducing the number of connecting wires required and simplifying the selection of the individual heaters.

Advantageously, the vertical trays may be shaped to include a ramp above each hook so that an article released from a hook does not collide with a lower hook in the same column during its fall towards the dispensing chute.

The heating element may be disposed within each hook but it is particularly convenient, in the case of the embodiment employing containers of which the point of suspension can be softened, for the hook itself to constitute the heating element, it being formed of a length of resistance wire which can be connected across a power supply.

The invention will now be described further, by way of example, with reference to the accompanying drawings, in which: Figure 1 is a perspective view of a container for an article of food to be dispensed from a freezer compartment, and Figure 2 is a schematic partial perspective view of a tray for supporting containers as shown in Figure 1.

The container 10 in Figure 1 is a box cardboard box 12 or possibly a paper or polythene bag containing a food article to be dispensed. The construction of this part of the container is not relevant to the invention. The box 12 is designed to be suspended from a hook 14 and, to this end, it is provided with a flap 16 having a hole 18 through the hook 14 passes. At least the flap 16 is made of a material, such as polypropylene, which softens with the application of heat.

The tray 20 shown in Figure 2 is intended to be stacked vertically in a freezer compartment and is made of an electrically insulating plastics material suitable for this purpose. The tray is formed with hooks 14 arranged in several rows and columns, each being intended to support a container 10 of the type shown in Figure 1.

The hooks 14 are formed of resistance wire and its reverse side of the tray 20 carries conductors which lead to the individual hooks to permit any selected hook to be heated separately. The conductors may be row and column conductors applied as a printed circuit to the trays or may comprise individual wires.

The trays are not flat but are shaped with ramps 22.

The ramped surface is designed to prevent a container falling from a higher hook being accidentally impeded from falling by a lower hook 14. Thus the ramps need to project further than the hooks 14.

The individual trays are intended to slide in and out of a rack system disposed in a freezer compartment, in a manner similar to the mounting of the printed circuit boards of a computer. This simplifies loading of the trays and enables efficient utilisation of the space within the freezer compartment.

In use, any given column on a tray should be loaded with goods of the same type. When this article is selected for dispensing the hook of the lowermost occupied position in that column is heated by passing current through it, the hook being itself made of resistance wire. The heat generated melts the plastics material of the flap 16 above the suspension hole 18 and the container falls under its own weight into a compartment from which it can be collected by the user. During its fall it is unimpeded by the hooks 14 beneath it, as it is guided over them by the ramps 22.

The advantages of the dispensing mechanism are its inherent simplicity and also its reliability under cold operating conditions, such as in a freezer compartment of a hot food vending machine. Each container is separately supported and cannot be frozen together with other containers. The main problems caused by freezing occur at the point of release and in the present invention.since heat is applied to effect the release, the effects of temperature are totally circumvented.

The hooks need not constitute the heating elements and it is alternatively possible to provide separate heaters to heat the hooks. Further, the effect of the heat need not be to act on the container but it may act on the hook to make it retract or change shape so as to release the container. The essential feature of the invention is that the release of the container 10 from a hook 14 is effect by the application of heat so as to avoid problems caused by freezing of the release mechanism.

Once the container has been released in a hot food vending machine, it will fall into a microwave oven which will first heat the article and then open a door to allow the heated food article to be retrieved by the user.

It is possible to monitor the falling of a container into the microwave oven in order to ensure that an article has been dispensed. Such monitoring can be effected optically, electrically or mechanically depending on the nature of the container. If an article is not dispensed, the steps may be taken to activate the heat hook a second time and if necessary to attempt to retrieve a similar article from another if all prior attempts fail.

The dispensing of a food article in such a food vending machine can be effect under micro-computer control, the computer serving to select the hook to be heated in dependence upon the selection made by the user and also to synchronise the operation of the door mechanism and the oven. The oven can furthermore be energised for different lengths of time, depending on the article to be heated.

Claims

1. A method of dispensing articles which comprises suspending the articles from individual hooks and applying heat to a hook in order to release a selected article to be dispensed, the application of heat serving to release the container from the hook.

2. A method as claimed in claim 1, wherein the articles to be dispensed are packaged in containers each having a portion from which the container can be suspended, at least the portion of the container from which it can be suspended being made of a material capable of being softened or melted by the application of heat, and the heat applied to the hooks serves to weaken the container so that it may fall off the hook under its own weight.

3. A method as claimed in claim 1, wherein the hook is formed to change shape on the application of heat to permit the article to fall under its own weight.

4. Apparatus for dispensing articles which comprises a plurality of hooks each for supporting a respective article, and means for selectively heating any individual hook, the application of heat to a hook being capable of releasing the article suspended on that hook, whereby the article may fall from the hook under its own weight.

5. Apparatus as claimed in claim 4, wherein each article is packaged in a container having a portion from which it can be suspended, at least the latter portion of each container being made of a material capable of being softened or melted by the application of heat.

6. Apparatus as claimed in claim 4 or 5, further comprising means for monitoring that an article has been released.

7. Apparatus as claimed in any of claims 4 to 6, in which the hooks are arranged on vertical trays which may be withdrawn from the dispensing apparatus for refilling.

8. Apparatus as claimed in claim 7, wherein the hooks on each tray are disposed in rows and columns so that the heating elements associated with the hooks may be connected in a matrix, thereby reducing the number of connecting wires required and simplifying the selection of the individual heaters.

9. Apparatus as claimed in claim 7 or 8, wherein the vertical trays are shaped to include a ramp above each hook so that an article released from a hook does not collide with a lower hook in the same column during its fall from the tray.

10. Apparatus as claimed in any of claim 5 or any claimed appended thereto, wherein each hook is formed or resistance wire and acts a a heating element.

11. Dispensing apparatus constructed, arranged and adapted to operate substantially as herein described with reference to and as illustrated in the accompanying drawings.