GB2284805A

GB2284805A - Dispensing heated food products

Info

Publication number: GB2284805A
Application number: GB9325650A
Authority: GB
Inventors: Leslie George Hamilton
Original assignee: EXPRESS CHEF Ltd
Current assignee: EXPRESS CHEF Ltd
Priority date: 1993-12-15
Filing date: 1993-12-15
Publication date: 1995-06-21
Anticipated expiration: 2013-12-15
Also published as: GB2284805B; GB9325650D0

Abstract

An apparatus for dispensing heated food products comprises a housing 11, in the upper part of which is a freezer compartment 27 having a trap door 69 and at least one magazine in the form of an wire helix 31 adapted to carry food packages P. Beneath the freezer compartment there is a cylindrical r.f. microwave oven 15 supported for rotation about its longitudinal axis. The wall of the oven has an aperture 49. Control means is operative to control the angular displacement of the oven 15 such that, during a cycle, a package P, released from the helix 31, passes through the aperture 49 into the oven 15. Further rotation of the oven 15 brings the aperture 49 to a position at which it is closed by a radiation opaque plate supported by the housing 11, magnetrons of the oven 15 being then activated to heat-treat the package. Further rotation of the oven brings the aperture 49 to a position whereat the heat-treated package P is discharged to a retrieval chute 17. <IMAGE>

Description

Dispensing Products This invention relates to dispensing apparatus for dispensing packages of food products, singly, after their heating within the apparatus.

According to the invention, an apparatus for dispensing, on demand, packages of food products, singly, after heat treatment thereof within the apparatus, comprises: an apparatus frame: and, supported with respect to said frame: a magazine adapted to hold a multiplicity of the aforementioned packages; an r.f. microwave oven having an oven body within which is the heat treatment space for said packages, being a body having a boundary wall at least a part of which has a cylindrically curved outer surface and an aperture through said wall part, and first and second boundary walls at the ends, respectively, of the first mentioned boundary wall, and which is supported for angular displacement about the axis of symmetry of said cylindrical surface; oven drive means operable to produce angular displacement of said oven about said axis;; radiation opaque closure means supported with respect to said frame, being such and so disposed as, at a certain angular displacement of the oven about said axis, to cooperate with the oven wall around the edge of said aperture such as to provide a shield thereacross serving substantially to confine to the oven interior electromagnetic radiation developed for heat-treatment of packages received within the oven; a package retrieval station; and, operating-cycle control means to control the several operative parts of the apparatus in such manner, at such times, and for such durations, that, during an operatingcycle, the oven is angularly displaced to said certain position at which a demanded package may be discharged through said aperture into the oven, then to the position at which said aperture is shielded by said closure means, and, being so shielded, is caused to be energized by the r.f.

power generator means of the oven at a power level and for a duration such as to effect a predesignated heat treatment of the package, and, after such heat treatment, is caused to be angularly displaced to a position such that said aperture is at the position at which a so-treated package is enabled to pass through said aperture to said package retrieval station.

Advantageously, the apparatus incorporates package dispenser means operable to convey packages, after heat treatment thereof, from said oven aperture, to said package retrieval station.

The apparatus may incorporate a freezer compartment within which said magazine is located.

Said magazine may comprise: an helically extensive part providing, between the convolutions thereof, an helically extensive space for the reception at positions therealong of respective ones of a multiplicity of the packages, and being rotatable with respect to the apparatus frame about the longitudinal axis of the helix; drive means operable to produce, an angular displacement of said body about said axis; and a part fixed with respect to said frame, having a surface adapted to be contacted by packages and which, by the prevention of rotatory movement of said packages about said axis by reason of such contact, is operable to constrain the packages to progress along said helical magazine towards a package discharge end thereof.

The apparatus may comprise: means (hereinafter referred to as "package release means") operable, with the oven angularly displaced about said axis by said oven drive means to a certain position, so as to cause a package discharged, by demand, from said magazine to pass through said aperture into the oven.

The package release means may comprise barrier means displaceable between a position at which it serves to arrest a package to be discharged into the oven and a package release position at which a package so arrested is enabled to pass, under gravity, through said oven aperture, into the oven.

The barrier means may comprise: a wall having an aperture therein; normally closed closure means for said aperture; and, means operable to move said barrier wall aperture closure means between open- and closed- aperture positions thereof.

The apparatus may comprise: bracket means secured with respect to said apertured wall and having an aperture therethrough in alignment with the aperture in said wall; and in which: the oven is supported by and is angularly displaceable within bearing means provided in said bracket.

Said radiation-opaque oven-aperture closure means may comprises a part dependant from said bracket and having, confronting said cylindrically curved oven outer surface, a surface of complementary cylindrical curvature.

Said oven-aperture closure part may be hingedly connected to said bracket; and there may be spring means biassing said closure part towards said oven outer surface.

The means operable to move said barrier wall aperture closure means may comprise an arrangement mechanically coupled to the oven and operative when, in response to a demand, the oven is angularly displaced to the position at which said oven aperture is at a predetermined position said wall aperture closure means is at the aperture-open position.

The aforesaid wall aperture closure means may comprise a trap door.

The aforesaid apertured wall may have first and second guide portions which extend along opposite sides, respectively, of said aperture; and said trap door is movable in its own plane in said guide portions.

The r.f.electromagnetic power generator means of the oven may comprise at least one magnetron, the radiation propogation element of which project into the oven interior through an aperture in an end boundary wall part of the oven; and a deflector part may be mounted on the interior surface of said boundary wall bridging said radiation propogation element deflection plate members, said deflector part being dimensioned and are positioned, such as, to give rise to a substantially optimum r.f. power distibution within the oven interior.

The foregoing and other features of an apparatus in accordance with the invention are hereinafter described with reference to the accompanying drawings in which: Fig.l shows, diagrammatically, a front elevation of a fast-food, package-dispensing, apparatus with the shell of the lower part thereof removed and the shell of the upper part shown broken away to reveal interior features; Fig.2 shows, diagrammatically, a side elevation of the apparatus with the shell of the lower part removed and the shell of the upper part broken away; Fig.3 is an exploded diagrammatic representation of the oven of the apparatus; and, Figs.4 to 9 show, diagramatically, a fast-food package dispensing apparatus at various stages during the course of a cycle of operation thereof.

An apparatus for dispensing, on demand, packages P of food products, singly, after the heating thereof within the apparatus, comprises: a cuboidal shell part 11 formed of fibreglass mat in several panels secured together by adhesive bonding material except where access to the apparatus interior must be sought, the panels being there attached to the remainder of the shell by means permitting the displacement thereof to expose the apparatus interior; and, supported with respect to said shell part 11: a magazine 13 adapted to hold a multiplicity of said packages P; an r.f.microwave oven 15; a package retrieval hopper 17; package dispenser means, being a chute 19, for conveying packages P from the oven 15 to the package retrieval hopper 17; oven drive means 21; radiation-opaque oven-aperture closure means 23; and operating-cycle control means of a composite and distributed character, to be discussed further hereinafter.

The shell 11 is given a structural rigidity by providing in the upper part 25 thereof, a freezer compartment 27, the floor of which has a central aperture 29.

The magazine 13 is constituted by four wire helices, as 31, having end portions 31a brazed or welded to axially extensive wire parts, as 33, the wire helices 31 being supported with said wire parts 33 respectively held vertically between four cantilevered upper brackets, as 35, respectively, and four corresponding cantilevered bottom locating rods, as 37, respectively, the four helices 31 being situate at the four corners of a notional rectangle.

A plate 39 is attached to the four locating rods 37 at the ends thereof remote from their positions of attachment to the apparatus shell 11; and attached to the plate 39 at the central point thereof, there is a mercury switch 41.

The r.f. microwave oven 15 has an oven body 43, being a body having a boundary wall 45 at least the central part 45a of which has a cylindrically curved outer surface 47 and an aperture 49 through said wall part 45a, and first and second boundary walls 51a,51b, respectively, at the ends 53a,53b, respectively, of the boundary wall 45.

Secured to the underside of the freezer compartment floor, within the lower part 55 of the apparatus, there is a bracket 57 having a step-down recessed portion 59, the bottom of which forms a platform 61 pierced with an aperture 63 in alignment with the freezer compartment floor aperture 29; and the oven body 43 is supported by and is angularly displaceable about the longitudinal axis X---X within bearing means 65a,65b, provided in the bracket 57.

The radiation-opaque, oven-aperture closure means 23 comprises a part dependant from the bracket 57 and having, confronting said cylindrically curved oven outer surface 47, a surface 67 of complementary cylindrical curvature.

The oven-aperture closure part 23 is connected to the bracket 57 at a hinge joint (not shown); and a prestressed spring (not shown), incorporated with the hinge of the closure part 23, biasses the closure part 23 towards the oven outer surface 47 such that a good radiation seal is effected around the aperture 49 of the oven body 43. A trap door 69, slideable in said recess portion 65, is coupled to the oven body 43 by a fine chain 71 which passes around idler pulleys 72.

The wire helices 31, provide, between the convolutions thereof a helically extensive space 73 for the reception at positions therealong of respective ones of the multiplicity of the packages P. The wire helices 31 are rotatable about their wire support parts 33, that is to say, about their longitudinal axes Y---Y under rotary drive to be imparted to the wire parts 31 by separately selectively energizable electric motors, as 75.A part 77, being insulating material lining the side wall of the freezer compartment 25 has a surface adapted to be contacted by the packages P and, by the prevention of rotatory movement of said packages about said axis Y---Y, as a result of such contact, operable, with rotation of the wire helices 31 about their axes Y---Y, to constrain the packages P held thereby to progress along said helical space 73 towards a package discharge end 79 thereof.

Considering the oven 15 in greater detail, the wall 45 of the oven body 43 which is of an e.m. radiation opaque material, in the example, stainless steel, is substantially cylindrical throughout its length; and the end boundary walls 51a,51b, are constituted as first and second stainless steel end-closure caps. The end-caps 51a,51b, support first and second magnetrons 81a,81b, respectively, the r.f propogation electrodes, as 83, of which project into the oven interior from the end-caps 51a,51b. Two microwave deflection top hat-section plate members 85a,85b, respectively, are mounted on the interior surfaces, as 87, respectively to bridge the electrodes 83.

The deflection plate members 85a,85b, are dimensioned and are positioned with respect to their respective magnetrons 81a,81b, as the case may be, such as, in operation of the apparatus, to provide the optimum r.f.

energy distibution within the oven interior.

Magnetron cooling fans 87a,87b, respectively, and fan deflection elements 89a,89b, respectively, are carried, also, by the end-caps 51a,51b, the fans 87a,87b, on brackets 91a,91b, respectively.

The oven drive means 21, whereby the oven may be angularly displaced about the axis X---X is constituted as a d.c. electric motor having its casing 93 fixed to one 95b of two dependant end arms 95a,95b, respectively, of the bracket 23 with the output shaft 95 of the motor projecting through an aperture 97 in said arm 95b.The output shaft 95 and the rotor of the motor 21 are coupled by way of a suitable step-down gearing, such for example, as a worm and helical gear wheel arrangement (not shown) housed within the motor casing 53; and the output shaft 95 and the oven body 43 are connected by a coupling comprising a first yoke member 97 and a bush 99 securing the bridge portion lOlb of the yoke member 97, at the centre point of said bridge portion, the free ends, 103a,103b, of the arms of the yoke member 97 being rigidly secured to the oven body 43 at the end cap 51b thereof.

At the opposite end of the oven 15 there is a second yoke-shaped coupling part 97b the free ends, 105a,105b, of which are, as before, rigidly secured to the oven body 43 at the position of the other end cap 51a. The arm 95a of the bracket 57 carries three contact sets, of which two 107a,107b, only, are shown, at positions determined by the operating cycle of the apparatus; and a cam part 109 mounted at the end of a spindle projecting axially from the yoke part 97b has a form such as, during each operating cycle, to cause said contact sets to be opened and closed at predetermined times during the cycle as dictated by the actions to be performed.

The oven 15 has an inner member 111 of an r.f. radiation transmissive material, such, for example, as polypropylene, providing a box-shaped compartment 113 for the reception of a package P to be dispensed from the apparatus after heat treatment in said compartment 113. Within the box compartment 113 there is a turntable 115.

The package dispenser chute 19 for conveying packages from oven to the package retrieval hopper 17 extends from a position adjacent the apertured cylindrical oven surface 31 to the package receiving end 17a of the hopper 17.

In addition to the apparatus parts as previously described or referred to, the apparatus also incorporates power distribution unit 117, a freezer compressor unit 119; and a hinged door 121 in the front wall of the upper freezer gives access to the interior thereof for the purpose of loading.

At the commencement of each operating cycle, the oven body 43 occupies the position represented in Fig.9, that is to say, the position adopted at end of the next preceding cycle of operation in the delivery of a package P, heat treated in the box-shaped compartment 113 of the inner member 111 of the oven 15, to the retrieval hopper 17.

The apparatus operating-cycle control means, which serves to control the several operative parts of the apparatus in the progress of a package P to be heat treated, from a lowest package position of a wire helix 31 to the point in time at which it is delivered, heat treated to the retrieval hopper 17, comprises, in addition to circuitry including various switch elements (not shown), whose functions will be apparent from the description given hereinafter as to the operation of various apparatus parts during an operating cycle, a digital ROM, suitably programmed in accordance with the requirements of the programme of operation.

An operating cycle is initiated by the insertion of coinage of appropriate value in a slot (not shown) provided in the apparatus, followed by the depression of a selected one of four buttons respectively associated with the four wire helices 31.

Depending upon the button selected, the appropriate magazine drive motor 75 is energized, the wire helix 31 associated therewith turning about its axis Y---Y and the packages P held thereby progressing in unison downwardly until, the lowest package P being released, after a certain rotation, from the confines of the helix, the so-released package P is arrested in its fall by the closed trap door 69. In falling, the released package P makes brushing contact with the mercury switch 41, the ensuing operation of the switch 41 interrupting the circuit to the motor 75, thereby bringing to rest the helix 31 being rotated thereby.

In addition to terminating action of the motor 75, operation of the switch 41 closes a circuit to the oven body d.c.

drive motor 93, the latter motor turning the oven body 43, in a clockwise sense, through (Figs.4 to 7) an angle somewhat in excess of 180, to the position shown in Fig.7, as determined by the cam operated closure of the contact set lû7a. In the course of execution of the displacement of the oven body 43 through such angle, the oven body, acting through the agency of the chain 71, causes the trap-door 69 to move along the recess 59 in the bracket 57, the movement of the trap-door to the fully open position coinciding with the arrival of the oven body aperture 49 at the position shown in Fig.7., the package P, formerly arrested by the then closed trap door, falling through the aperture 63 of the bracket 57 and the upwards-facing oven body aperture 49 into the box compartment 113 within the oven body 43. A signal developed by the ROM after a predetermined interval causes the d.c. motor 21 to be energized for angular displacement about the axis X---X, but in the reverse sense, the oven body 43 being rotated to the position shown in Fig. 9., a position determined by the cam operated closure of contact set 107b. In the latter position, the aperture 49 of the oven body 43 is, of course, closed against the escape of e.m. radiation by the part 23 dependant from the bracket 57. Accordingly, closure of the contact set 107b serves, also, firstly to energize the motor drive (not shown) to the turntable 115 and, secondly, to initiate powering of the magnetrons 81a,81b.Powering of the magnetrons continues for a preset period, calculated to effect the desired heat treatment of the package P being rotated by the turntable 115. At the end of the prescribed heat treatment period for the package P, power is removed from the magnetrons and the turn-table and the oven body drive motor 21 again energized, the oven body being driven counter-clockwise further until cam operation of the contact set 107c causes the oven body to come to rest at the apparatus rest position (Fig.9). At that position, the heat treated package P is able to slide from the box-shaped compartment 113 through the oven body aperture 49, to be conveyed by the chute 19 to the retrieval hopper 17. The operating cycle is complete.

Claims 1. An apparatus for dispensing, on demand, packages of food products, singly, after heat treatment thereof within the apparatus, which comprises: an apparatus frame: and, supported with respect to said frame: a magazine adapted to hold a multiplicity of the aforementioned packages; an r.f. microwave oven having an oven body within which is the heat treatment space for said packages, being a body having a boundary wall at least a part of which has a cylindrically curved outer surface and an aperture through said wall part, and first and second boundary walls at the ends, respectively, of the first mentioned boundary wall, and which is supported for angular displacement about the axis of symmetry of said cylindrical surface; oven drive means operable to produce angular displacement of said oven about said axis;; radiation opaque closure means supported with respect to said frame, being such and so disposed as, at a certain angular displacement of the oven about said axis, to cooperate with the oven wall around the edge of said aperture such as to provide a shield thereacross serving substantially to confine to the oven interior electromagnetic radiation developed, by the r.f. power generator means of the microwave oven, for heat-treatment of packages received within the oven; a package presentation station; package dispenser means operable to convey packages, after heat treatment thereof, from said oven aperture, to said package presentation station; and, operating-cycle control means to control the several operative parts of the apparatus in such manner, at such times, and for such durations, that, during an operatingcycle, the oven is angularly displaced to said certain position at which a demanded package may be discharged through said aperture into the oven, then to the position at which said aperture is shielded by said closure means, and, being so shielded, is caused to be energized by the r.f.

2. n apparatus as claimed in claim 1 and which incorporates package dispenser means operable to convey packages, after heat treatment thereof, from said oven aperture, to said package retrieval station.

3. An apparatus as claimed in claim 1 or 2 and which comprises a freezer compartment; and said magazine is within said freezer compartment.

4. An apparatus as claimed in claim 1,2 or 3 in which said magazine comprises: an helically extensive part providing, between the convolutions thereof, a helically extensive space for the reception at positions therealong of respective ones of a multiplicity of the packages, and being rotatable with respect to the apparatus frame about the longitudinal axis of the helix; drive means operable to produce, an angular displacement of said body about said axis; and a part fixed with respect to said frame, having a surface adapted, when, in use, said helically extensive space is occupied by a multiplicity of packages, to be contacted by said packages and which, by the prevention of rotatory movement of said packages about said axis as a result of such contact, is operable to constrain the packages to progress along said helically extensive magazine towards a package discharge end thereof.

5. An apparatus as claimed in claim 1,2,3 or 4 and which comprises: means (hereinafter referred to as "package release means") operable, with the oven angularly displaced about said axis by said oven drive means to a certain position, so as to cause a package discharged, by demand, from said magazine to pass through said aperture into the oven.

6. An apparatus as claimed in claim 5 in which the package release means comprises barrier means displaceable between a position at which it serves to arrest a package discharged from said magazine and a package release position at which a package so arrested by the barrier means is enabled to pass, under gravity, through said oven aperture, into the oven.

7. An apparatus as claimed in claims 6 in which said barrier means comprises: a wall having an aperture therein; normally closed closure means for said aperture; and, means operable to move said barrier wall aperture closure means between open- and closed- aperture positions thereof.

8. An apparatus as claimed in claim 7 and which comprises: bracket means secured with respect to said apertured wall and having an aperture therethrough in alignment with the aperture in said wall; and in which: the oven is supported by and is angularly displaceable within bearing means provided in said bracket.

9. An apparatus as claimed in claim 8 in which: said radiation-opaque oven-aperture closure means comprises a part dependant from said bracket and having, confronting said cylindrically curved oven outer surface, a surface of complementary cylindrical curvature.

10. An apparatus as claimed in claim 9 in which said ovenaperture closure part is hingedly connected to said bracket and spring means biasses said closure part towards said oven outer surface.

11. An apparatus as claimed in any of claims 7 to 10 in which said means operable to move said barrier wall aperture closure means comprises an arrangement mechanically coupled to the oven and operative when, in response to a demand, the oven is angularly displaced to the position at which said oven aperture is at a predetermined position said wall aperture closure means is at the aperture-open position.

12. An apparatus as claimed in claim any of claims 7 to 11 in which said wall aperture closure means comprises a trap door.

13. An apparatus as claimed in claim 12 in which said apertured wall has first and second guide portions which extend along opposite sides, respectively, of the aperture thereof; and said trap door is movable in its own plane in said guide portions.

14. An apparatus as claimed in any preceding claim in which the r.f.electromagnetic power generator means of the oven comprises at least one magnetron the radiation propogation element of which projects into the oven interior through an aperture in an end-cap part of the oven; and a deflector part is mounted on the interior surface of said end-cap part bridging said radiation propogation element deflection plate members said deflector part being dimensioned and are positioned, such as, to give rise to a substantially optimum r.f. power distibution within the oven interior.

15. An apparatus substantially as hereinbefore described with reference to the accompanying drawings.