WO1992012502A1

WO1992012502A1 - A device for heating items

Info

Publication number: WO1992012502A1
Application number: PCT/GB1991/002324
Authority: WO
Inventors: Paul Taylor
Original assignee: Ryebrook Foods Limited
Priority date: 1991-01-03
Filing date: 1991-12-27
Publication date: 1992-07-23
Also published as: AU9114991A; GB9100092D0

Abstract

The invention provides a simple and compact device for heating items. The device comprises an item guide such as a cup for engaging an item in a first position and drive means for moving the item guide through an arc thereby to convey the item to and from a heating source. The heating source is preferably a microwave source. The invention also provides a vending machine including the above device.

Description

A DEVICE FOR HEATING ITEMS

The invention relates to a device for heating items and to a vending machine including the device.

A known example of a device for heating items is disclosed in International Patent Application No. WO86/04707. That document discloses a food storage heating and dispensing apparatus comprising a plurality of stacks of food containers above an oven housing. On operation of the apparatus, a container is released to fall from the stack into the oven housing. Depending upon the position of the stack, a conveyor may be used to position the fallen container. A large closure element is then pivoted to position it between the entrance to the oven housing and the stacks and a microwave source is actuated to heat the container of food. The closure element is then pivoted away and the conveyor is operated to eject the container from the oven housing to a system of dispense flaps.

This system is relatively complex and includes a number of driven parts to manipulate a container and close off the oven, which may be undesirable. According to one aspect of the invention there is provided a device for heating items comprising a item guide for engaging an item in a first position and drive means for moving the item guide through an arc thereby to convey the item to the heating source and thence away from the heating source to a second position.

A device according to the invention is both simple and compact.

The drive means is preferably arranged to move the item guide through a partial or complete arc of a circle.

The guide may be of any suitable type and may conveniently define a cup to receive an item, or may define a bore to receive an item. Preferably, the device is such that when the guide has conveyed the item to the heating source, the guide together with other features of the device forms a protective chamber about the item. The heating source may be of any suitable type, but is suitably a microwave heating source and the protective chamber and is arranged to prevent microwave leakage. The heating source may be arranged to heat the item from one direction, conveniently from below the item. Preferably, the heating source is also arranged to heat an item from another direction and may be arranged to heat an item from above and below. Where a microwave source is used, then, as microwaves only penetrate for a limited depth, by heating the item from two opposite directions, items of greater thickness can be heated. The heating source may thus comprise two heating units. Where the source is a microwave source, the source is conveniently associated with a wave guide which can be switched to direct microwaves in one direction or in an opposite direction onto an item. Thus only one heating unit may be used, or alternatively two units may be used such that both units can heat an item of low thickness from the same side, or an item of greater thickness can be heated from both sides.

An item may move in any suitable manner into the first position, or may be stored in the first position. Conveniently, however, an item moves vertically downwardly into the first position and preferably moves through an opening to the first position. Preferably, blocking means is provided to block the opening once the guide has engaged an item. Thus, once an item has moved into the first position and been engaged by the guide, it cannot be interfered with externally. Preferably, the blocking means is insulating and in that way any heat radiated by the product does not rise through the opening. Also, if items are being taken from a refrigerated store, cold air from the store does not fall through the opening. The blocking means conveniently comprises a surface connected to the guide. The surface may be a continuous annular surface and in a particularly preferred embodiment, that surface is an upper surface of a drum in which the guide is provided. The guide may however be provided in any suitable way and in an alternative embodiment the guide may be provided on an arm.

The item may be arranged to move vertically downwardly in two stages. In this way, the item is more likely to remain in the correct orientation and is less likely for example to fall onto one side. Preferably, an element is provided under the opening and onto which an item moves in the first stage of vertical downwards movement. The element is preferably connected in front of the guide so that as the guide moves into the first position, the element is moved away from the opening and an item on the element is moved by engagement with the wall of the opening off the wall and into the first position. Where the said blocking means comprises a surface connected to the guide, the element may comprise a continuation of the surface and where the surface is an upper surface of a drum, the element conveniently comprises another part of the upper surface of the drum.

The drive means may be of any suitable type and may include an electrical motor. The item guide is preferably arranged to stop at the heating source for a predetermined period of time. The drive means may include a continuously driven motor and in that case the drive means may operate in Geneva-stop motion.

The drive is particularly suited for inclusion as part of a vending machine and according to another aspect of the invention there is provided a vending machine including a device according to the first aspect of the invention described and including any or none of the sub-features mentioned in relation thereto and in which items are dispensed from the second position.

Items may be moved into the first position from an item store. The items may be of any suitable type but the items which the device is arranged to heat are preferably food products.

In the food storage, heating and dispensing apparatus disclosed in International Patent Application No. WO86/04707, as discussed, a plurality of stacks of food containers are stored above an oven housing. By actuation of the apparatus, a container is released from a selected stack to fall onto a conveyor and the conveyor may then need to be used to position the fallen container. This system in which a fallen container must be manipulated into position after selection may not be as accurate or compact as might be desirable.

According to a third aspect of the invention, there is provided a device for dispensing a selected item from a store comprising a track along which items are moved and an openable break in the track to enable a selected item to be diverted therefrom to be dispensed.

In this way, an item is always dispensed at the same position and the mechanism for moving the item in the store can be compact. The track may take any suitable form but preferably comprises a pair of rails.

Preferably, a selected item is diverted onto a further track.

The track may be openabie by movement of one part vertical in relation to another part, an item can thus move downwardly from the track under gravity. The track conveniently includes a hinge about which a section of the track is swingable. Preferably, where a further track is provided, it lies beneath the first track. The items are preferably pushed along the track by push means which preferably comprises at least one push member arranged to push each item on the track. The push members are preferably arranged to continue to push a selected item along the further track. In this way the push members serve a dual purpose. Conveniently then the push members are arranged vertically.

The items can conveniently be arranged in stacks on the track.

According to a fourth aspect of the invention there is provided a vending machine including a device according to the third aspect of the invention and including any or none of the sub-features mentioned in relation thereto.

Preferably the vending machine also includes a device according to the first aspect of the invention and including any or none of the sub-features mentioned in relation Lheieto. An embodiment of the invention will now be described by way of example and with reference to the accompanying drawings, in which:

Fig. 1 is a perspective view of the device with certain parts not shown for clarity;

Fig. 2 is a top plan view of the drum of the device;

Fig. 3 is a perspective view of part of the carousel of the machine incorporating the device; and

Fig. 4 is a partial elevation illustrating the heat source of the device.

The device 10 comprises a drum 11 of broad diameter and low height. Upper and lower plates 12, 13 lie closely adjacent the upper and lower surfaces of the drum 11. The drum 11 is arranged to be turned on a vertical central spindle 14. A member 16 is mounted on the spindle below the lower plate 13 and includes three arms 9 extending radially outwardly. Each arm 9 includes a radial slot 15 extending from the outer end of the arm 9. The slots 15 are intersected by a pin 17 which is upstanding on a disc 18. The disc 18 is mounted co-axially on a spindle 19 which has its axis parallel to the spindle 14. The spindle 19 is driven by an electric motor 20. The pin 17 is provided at the edge of the disc 18 such that the spindle 14 is driven by the motor 20 through the disc 18, pin 17 and member 16 in Geneva stop motion.

Above the upper plate 12 is provided a track 21 comprising a pair of parallel rails 22 arranged in concentric circles co-axial with the spindle 14. The track 21 includes an openable section where adjacent portions 23 of the two rails 22 are hinged to be swingable upwardly. Beneath the hinges 24 is the beginning of a second track 25 which also comprises two rails 26. The second track 25 lies directly beneath the first track 21 but is angled downwardly from adjacent the hinges 24 to a position adjacent an aperture 27 in the upper plate 12. Closely above the end of the track 25 is provided a wheel 37 having radial spikes and which is free to rotate about an axis parallel to the radial direction in relation to the track 25.

There is an aperture 28 in the lower plate 13 at an angle of just more than 120° to the aperture 27 about the axis of the spindle 14. A chute (not shown) is provided under the aperture 28 and leads to a dispense flap (not shown) . A through bore 38 is defined in the u ji — u .m_ -i I iI

cross-section to the apertures 27, 28. At a position 120° in the other manner of rotation from the aperture 28 a microwave source 29 is provided beneath the lower plate 13. The lower plate 13 is made from metal except for the region adjacent the microwave source 29 which is made from a microwave inert material such as pyrex. The upper plate 12 is also made of metal except for a region directly above the microwave source 29 which is again made from microwave inert material. The two inert regions are connected by a wave guide 30 and a second microwave source 31 is arranged to emit microwaves to the wave guide 30 at a position mid-way along the wave guide 30. A switch (not shown) is provided to enable microwaves emitted by the second microwave source 31 to be diverted either to the inert region of the upper plate 12 or to the inert region of the lower plate 13. The wave guide 30 and microwave sources 29, 31 were omitted from Fig. 1 for clarity.

A carousel 32 is provided above the track 21. The carousel 32 consists of a plurality of linked cages 33 above the track 21 and each arranged to support a stack of items on the track 21 and extend to just above the upper plate 12. From each cage 33 depend two push members 34 which are positioned between the rails 22 cf the track 21. Each cage 33 carries a projection 35 and the projections 35 are at different heights on each cage 33. The projections 35 actuate microswitches (not shown) to indicate the position of the carousel 32. Movement of the carousel is by an electric motor controlled by electronic circuitry (not shown) actuated by coin freed control means (not shown) which may be of known type.

In operation, the items may be food packs 36 stacked on the track 2 , each stack being supported by a cage 33 of the carousel 32. Each food pack 36 includes oppositely disposed tabs 40 which engage the rails 22. A user inserts coins into the machine to the value of the desired food product and selects in suitable known manner the desired food product which will correspond to one cf the stacks of food packs 36. The carousel 32 will then be rotated by the electric motor until the selected stack is immediately adjacent the openable section 23. The section 23 is then hinged upwardly about the hinges 24 and the lowest food pack 36 of the stack will thus drop through the break in the first track 21 onto the rails 26 of the second track 25. The push members 34 push the food pack 36 around on the first track and now continue to push the food pack along the second track 25. At the end cf the track 25, the lid of the food pack 36 engages the spikes of the wheel 37 as the food pack 36 is pushed under the wheel 37 by the push members 34. The food pack 36 which now has a line of perforations along its lid is pushed by the push members to the aperture 27 in the upper plate 12 and falls therethrough onto the upper surface of the drum 11. The electric motor 20 is then actuated and the drum 1 rotates. The bore 38 in the drum 11 initially lies just in front of the aperture 27 at an angle of 120° to the aperture 2S and the microwave source 29 as shown in Fig. 2. As the bore aligns with the aperture 27, the food pack 36 falls through the bore 38 onto the plate 13. The food pack 36 is thus dropped into the bore 38 in two stages, the first being a drop onto the upper surface cf the drum, which constitutes the aforesaid "element" and the second being a drop into the bore 38 itself. In this way the pack 36 more reliably stays the right way up.

The food pack is then pushed along the lower plate 13 by the wall of the bore 38 which constitutes the aforesaid "item guide". Through the Geneva stop drive between the motor 20 and the spindle 14, rotation of the drum is halted when the bore 38 is directly above the first microwave source 29. If the food pack is of low thickness, the switch 39 will direct microwaves from the second source 31 through the wave guide to the same side of the bore 38 as the first source 29. If the food pack is of greater thickness, the switch will cause microwaves from the second source to take the alternative route through the wave guide so that they impinge on the food pack from above while microwaves from the first source impinge on the pack from below. The gap between the drum 11 and each of the adjacent plates 12, 13 is about 2-3mm which has been found to be sufficient to eliminate microwave leakage. The perforations allow a release of pressure of e.g. steam from the heated contents of the pack. The upper surface of the drum provides the surface which constitutes the aforesaid "blocking means" to block the aperture 27 once the food pack 36 has been collected by the drum 11. Once the food pack has been heated for the required, pre-determined length of time, the drum 11 is rotated through a further 120° so that the bore 38 is aligned with the aperture 28 and the food pack falls through the aperture 28 onto the chute (not shown) and down to the dispense flap (not shown) for collection by the user.

It is thus seen that the machine described operates in a simple and efficient manner, with controlled movement of a food pack and a minimum of drive motors required.

Claims

1. A device for heating items comprising a item guide for engaging an item in a first position and drive means for moving the item guide through an arc thereby to convey the item to the heating source and thence away from the heating source to a second position.

2. A device as claimed in claim 1, wherein the drive means is arranged to move the item guide through a partial or complete arc of a circle.

3. A device as claimed in claim 1 or claim 2, wherein the guide defines a bore to receive an item.

4. A device as claimed in claim 1, 2 or 3, wherein the device is such that when the guide has conveyed the item to the heating source, the guide together with other features of the device forms a protective chamber about the item.

5. A device as claimed in claim 4, wherein the heating source is a microwave heating source and the protective chamber and is arranged to prevent microwave leakage.

6. A device as claimed in any preceding claim, wherein the heating source is arranged to heat the item from one direction.

7. A device as claimed in claim 6, wherein the heating source is arranged to heat the item from below.

8. A device as claimed in claim 6 or claim 7, wherein the heating source is also arranged to heat an item from another direction.

9. A device as claimed in claim 8, wherein the heating source is arranged to heat an item from above and below.

10. A device as claimed in claim 8 or claim 9, wherein the heating source comprises two heating units.

11. A device as claimed in claim 8, 9 or 10 when dependent on claim 5, wherein the source is associated with a wave guide which can be switched to direct microwaves in one direction or in an opposite direction onto an item.

12. A device as claimed in any preceding claim, wherein an item moves vertically downwardly into the first position.

13. A device as claimed in claim 12, wherein an item moves through an opening to the first position.

14. A device as claimed in claim 13, wherein blocking means is provided to block the opening once the guide has engaged an item.

15. A device as claimed in claim 14, wherein the blocking means is insulating.

16. A device as claimed in claim 14 or claim 15, wherein the blocking means comprises a surface connected to the guide.

17. A device as claimed in claim 16, wherein the surface is a continuous annular surface.

18. A device as claimed in claim 17, wherein the continuous annular surface is an upper surface of a drum in which the guide is provided.

19. A device as claimed in any of claims 12 to 18, wherein the item is arranged to move vertically downwardly in two stages.

2C. A device as claimed in claim 19, wherein an element is provided under the opening and onto which an item moves in the first stage of vertical downwards movement.

21. A device as claimed in claim 20, wherein the element is connected in front of the guide so that as the guide moves into the first position, the element is moved away from the opening and an item on the element is moved by engagement with the wall of the opening off the wall and into the first position.

22. A device as claimed in claim 20 or claim 21 when dependent on claim 16, wherein the element comprises a continuation of the surface.

23. A device as claimed in claim 22 when dependent on claim 18, wherein the element comprises another part of the upper surface of the drum.

24. A device as claimed in any preceding claim, wherein the drive means includes an electrical motor.

25. A device as claimed in any preceding claim, wherein the item guide is arranged to stop at the heating source for a predetermined period of time.

26. A device as claimed in any preceding claim, wherein the drive means includes a continuously driven motor.

27. A device as claimed in claim 26, wherein the drive means operates in Geneva-stop motion.

28. A vending machine including a device as claimed in any preceding claim.

29. A vending machine as claimed in claim 28, wherein items are moved into the first position from an item store.

30. A vending machine as claimed in claim 28, wherein the items which the device is arranged to heat are food products.

31. A device for dispensing a selected item from a store comprising a track along which items are moved and an openable break in the track to enable a selected item to be diverted therefrom to be dispensed.

32. A device as claimed in claim 31, wherein the track comprises a pair of rails.

33. A device as claimed in claim 31 or claim 32, wherein a selected item is diverted onto a further track.

34. A device as claimed in any of claims 31 to 33, wherein the track includes a hinge about which a section of the track is swingable.

35. A device as claimed in any of claims 31 to 34, wherein the track is openable by movement of one part vertical in relation to another part.

36. A device as claimed in claim 33 or claim 34 or 35 when dependent thereon, wherein the further track lies beneath the first track.

37. A device as claimed in claim 36, wherein the items are pushed along the track by push means.

38. A device as claimed in claim 37, wherein the push means comprises at least one push member arranged to push each item on the track.

39. A device as claimed in claim 38, wherein the push members are arranged to continue to push a selected item along the further track.

40. A device as claimed in claim 39, wherein the push members are arranged vertically.

41. A device as claimed in any of claims 31 to 40, wherein the items are arranged in stacks on the track.

42. A vending machine including a device as claimed in any of claims 31 to 41.

43. A vending machine as claimed in claim 28, 29 or 30 which includes a device as claimed in any of claims 31 to 41.