MANUFACTURE OF A REFRIGERATED MERCHANDISING UNIT

Abstract: A sliding curved lid refrigerated merchandising unit (1) has a cabinet (3) with a top opening defined by a chest frame (4). The opening is closed by upper and lower lids (5, 6). To manufacture the unit, a lid edging strip (10) is applied around a curved pane and a handle (45) and runners (46) are applied to the lid in a jig (49). The chest frame is assembled from frame members (61, 62, 63, 64) which are then ultrasonically welded. The welded joints are covered with an insulating and sealant foil (56) which is covered by a hot melt adhesive. Runners (70) are inserted into recesses in the front chest frame member (63). An inner liner (75) and an outer cabinet (76) are fitted to the chest frame and the cavity thus formed is filled with an insulating material. The lids (5, 6) are then fitted to the chest frame (4).

Description: "Manufacture of a Refrigerated Merchandising Unit" The invention relates to a method for manufacturing a sliding curved lid refrigerated merchandising unit- According to the invention, there is provided a method for manufacturing a sliding curved lid refrigerated merchandising unit comprising the steps of:~ assembling a chest frame comprising a pair of curved side chest frame members interconnected by front and rear chest frame members, the chest frame having an inner liner receiving recess and an outer cabinet body receiving recess, the front and rear chest frame members also having an upper track for receiving a top lid and a lower track for receiving a lower lid; forming a liner; applying a coil around the liner; inserting the liner with attached coil into the inner liner receiving recess of the chest frame; forming an outer cabinet body; inserting the outer cabinet body into the outer cabinet body receiving recess of the chest frame; injecting liquid foam reactants into the cavity defined between the liner and the outer cabinet body to form an insulating core; cutting notches in a length of lid edging strip; applying a sealant to the lid edging strip; applying the edging strip with sealant to a curved lid pane to form a curved lid; curing the sealant; applying a runner to the edging strip of the pane; inserting a lower lid thus formed in the lower track of the chest frame; and inserting a top lid thus formed in the upper track of the chest frame. In a preferred embodiment of the invention, the runner is inserted into a runner receiving slot of the edging strip. Preferably, the method includes the step of bonding a handle to the edging strip of the curved lid. Advantageously, the handle includes a handle grip part and a mounting part and the method includes the steps of:- inserting the handle grip part in a recess of a jig; applying adhesive to the exposed mounting part of the handle; mounting the edging strip of the curved lid to the adhesive on the handle mounting part; and clamping the lid to the handle. In one embodiment of the invention, the lid is clamped to the handle by a clamping means which is released automatically after a preset time. In this case, preferably the runner is applied to the edging strip when the clamping means is operated. In another embodiment of the invention, the chest frame members are moulded parts having formations which interengage with one another on assembly. Preferably, the method includes the step of ultrasonicaily welding the chest frame members together on assembly. In a particularly preferred arrangement, after assembly, a sealant and an adhesive are applied to the joints between the chest frame members prior to insertion of the liner and the outer cabinet body. Preferably, in this case the sealant includes a foil strip applied over the joints and the adhesive is a hot melt adhesive which melts on moulding of the insulating core. In a particularly preferred embodiment of the invention, the method includes the step of inserting runners in at least the front frame member of the chest frame. Preferably, the runners associated with the lower lid and top lid are inserted in the front frame member of the chest frame. In one embodiment of the invention, the or each runner is of wear resistant plastics material and the or each runner snap fittingly engages with a corresponding recess in the lid edging strip or chest frame member. In one embodiment of the invention, the lid edging strip is cut to a desired length and subsequently four V-notches are cut from the lid edging strip at locations to correspond with the corners of the curved pane. Preferably, the method includes the steps of:- turning the cabinet formed on insertion of the inner liner and outer cabinet body to the chest frame so that an open lid-receiving side of the cabinet is lowermost; lowering the open side of the cabinet onto an inner mould part; closing an outer mould part around the cabinet; and, after injection of the liquid foam reactants, curing the foam; the mould being moved during filling and/or curing so that the insulating foam fills the cavity. In a preferred arrangement, in this case the mould is moved by moving the mould about a longitudinal or transverse axis of rotation with respect to a mounting bed in which the mould is mounted. The invention will be more clearly understood from the following description thereof, given by way of example only, with reference to the accompanying drawings, in which:- Fig. 1 is a perspective view of a typical sliding curved lid refrigerated merchandising unit manufactured by the method of the invention; Fig. 2 is a partial cross sectional view on the line II - II in Fig. 1; Fig. 3 is a plan, partially cross sectional view of an apparatus used in a lid edge notching step of the method of the invention; Fig. 4 is a side partially cross sectional view of the apparatus of Fig. 3 in use; Fig. 5 is a view of a sealant application step used in the method of the invention; Fig. 6 is a perspective view of a sliding curved lid with the lid edge sealing strip applied; Fig. 7 is a cross sectional view on the line VII-VII in Fig. 6; Fig. 8 is a perspective view of a lid edge sealing strip clamping apparatus used in the method of the invention; Fig. 9 is a perspective view of a handle lid applying apparatus used in the method of the invention; Fig. 10 is an elevational view of the apparatus of Fig. 9 in another position of use; Fig. 11 is a cross sectional view on the line XI-XI of Fig. 9; Fig. 12 is a cross sectional view on the lines XII- XII of Figs. 9 and 10; Fig. 13 is a perspective view of a chest frame formed in the method of the invention; Fig. 14 is a perspective view from below of a detail of one joint of the chest frame of Fig. 13; Fig. 15 is a perspective view from above of one side member of the chest frame of Fig. 13; Fig. 16 is a perspective view of a moulding apparatus used in the method of the invention in an open configuration; and Fig. 17 is a side view of the moulding apparatus of Fig. 16, in use; Referring to the drawings, there is illustrated a method for manufacturing a sliding curved lid refrigerated merchandising unit according to the invention. One such sliding curved lid refrigerated merchandising unit is illustrated in Figs. 2 and 3 and indicated generally by the reference numeral 1. The merchandising unit 1 comprises a generally rectilinear refrigerated cabinet 3 having a top opening defined by a chest frame 4. The top opening is closed by an upper lid 5 and a lower lid 6 which are slidably mounted for sliding movement in the direction of the arrows indicated in Fig. 1 to gain access to refrigerated foods held in the merchandising unit 3. The upper lid 5 is of larger dimensions than the lower lid 6, however, the method of manufacturing is substantially identical. A lid edging strip 10 which is extruded from a suitable plastics material is clamped in position in a jig 15 as illustrated in Figs. 3 and 4 including a lower bed 16 having in this case four receiving slots, each for a length of edging strip 10. The jig 15 includes an upper clamping head 18 which is engaged against the edging strips 10 in use to hold the edging strips in position as V-notches 25 are cut in the strips 10 using cutting saws 20 travelling through suitably shaped guideways 19. The jig 15 is used to cut the edging strips 10 to length and to cut four V-notches 25 along the length thereof. An edging strip 10 having V-notches 25 cut therein is then laid flat on a table as illustrated in Fig. 5 and a sealant, typically a silicone sealant, is applied to the edging strip 10 from a gun applicator 30. Rubber seals 31 are also inserted in the edging strip 10 which is then wrapped around a curved glass pane 35 as illustrated in Figs. 6 and 7 to form either an upper or a lower lid 5, 6. The lid 5, 6 thus formed is then mounted in a jig 38 illustrated in Fig. 8 having two adjacent fixed walls 39, 40 against which the lid 5, 6 is clamped by corresponding movable walls 41, 42 respectively, which are operated by toggle handles 43, 44 respectively. This ensures the dimensional stability and uniformity of the lid 5, 6. After clamping, the lid 5, 6 is left for at least six hours to cure the sealant. The handle 45 and runners 46 are applied to the lid 5, 6 in a jig 49 which is illustrated in Figs. 9 to 12. The jig 49 includes a bed 50 having a recess 51 to receive a handle part 45 and lid edge supporting grooves 52 to support the lid in the jig. A movable curved clamping member 53 is operated by rams 54. In more detail, it will be noted that the handle 45 has a projecting handle part 45(a) which is inserted in the recess 51 in the jig 49 and a mounting ledge 45(b) to which a bead of adhesive is applied from a supply nozzle 55. The lid 5 or 6 is then placed on the jig and the rams 54 are operated, driving the clamping member 53 downwardly to engage the sealing edge strip of the lid 5 or 6 against the adhesive to bond the handle 45 to the frame. The rams 54 apply a pre-determined clamping force for a preset time after which the rams are automatically released allowing the lid to be removed from the jig 49. While the rams 54 are extended and the frame is clamped in position in the jig 49, the runners 46 are snap fittingly engaged in receiving recesses in the upper and lower edges in use of the edging strip 10 as will be particularly apparent from Fig. 11. Referring particularly to Figs 13 to 15, a chest frame 60 is assembled from four chest frame members, namely, two chest frame side members 61, 62, a front chest frame member 63 and a rear chest frame member 64. Each of the chest frame members 61 to 64 are injection moulded from a plastics material and each have interengaging projections such as a projection 65 on the side frame member 61 illustrated in Fig. 15 which interengage on assembly with corresponding recesses in adjacent chest frame members for engaging the frame members together. After assembly, the frame members 61, 62, 63, 64 are ultrasonicaily welded together. In addition, the welded joints between the adjacent frame members are covered with an insulating and sealant metal foil material 66 which in turn is covered with a hot melt adhesive 67 extending over the joint and beyond it. It will be noted that the front and rear frame member 63 includes tracks for the upper and lower sliding lids 5, 6. The tracks are partially defined by an inwardly extending front lip 68 under which the lids are fitted. Runners 70 associated with the upper and lower lids 5, 6 respectively are inserted into corresponding recesses in the front chest frame member 63. To reinforce the chest frame, metal insert plates may be inserted at appropriate locations in the frame 60. The chest frame 60 formed and assembled as described above, includes an inner first peripherally extending recess 72 for receiving an inner liner 75 of a refrigerator unit and an outer periphery extending recess 73 for receiving an outer cabinet 76. The liner 75 and cabinet 76 are spaced-apart to define therebetween a cavity which is filled with foam insulating material 78 using the moulding apparatus illustrated in Figs. 16 and 17 and indicated generally by the reference numeral 80. The moulding apparatus 80 includes a support bed defined by individual removable bed forming members 81 which are sized and shaped to conform with the chest frame 60 which is loaded onto the mould. With the chest frame lowermost, the cabinet is lowered onto an inner mould part 82 and an outer mould defined by four hinged and clampingly engageable side walls 83 and a top 84 are closed around the cabinet. The liquid foam reactants are then injected into the cavity defined between the outer cabinet 76 and the inner liner 75 and on injection the foam reacts expanding and on curing, filling the cavity. It will be noted that the mould 80 is movable on a transverse pivot axis for angular rotational movement about the axis as required to position the mould for optimum filling of the cavity with the insulating foam. The mould may be rotated to distribute the foam reactants either on filling and/or during curing. After moulding, the unit is checked and finally the lids 5, 6 are fitted as described above. The invention provides a highly efficient method for manufacturing a refrigerated sliding curved lid merchandising unit. A very high quality merchandising unit is produced with curved sliding lid units which are interengaged for free sliding movement in all conditions of use with a corresponding high quality chest frame. Many variations on the specific embodiments of the invention will be readily apparent and accordingly, the invention is not limited to the embodiments hereinbefore described which may be varied in both construction and detail.

Claims: CLAIMS 1. A method for manufacturing a sliding curved lid refrigerated merchandising unit comprising the steps of:- assembling a chest frame comprising a pair of curved side chest frame members interconnected by front and rear chest frame members, the chest frame having an inner liner receiving recess and an outer cabinet body receiving recess, the front and rear chest frame members also having an upper track for receiving a top lid and a lower track for receiving a lower lid; forming a liner; applying a coil around the liner; inserting the liner with attached coil into the inner liner receiving recess of the chest frame; forming an outer cabinet body; inserting the outer cabinet body into the outer cabinet body receiving recess of the chest frame; injecting liquid foam reactants into the cavity defined between the liner and the outer cabinet body to form an insulating core; cutting notches in a length of lid edging strip; applying a sealant to the lid edging strip; applying the edging strip with sealant to a curved lid pane to form a curved lid; curing the sealant; applying a runner to the edging strip of the pane; inserting a lower lid thus formed in the lower track of the chest frame; and inserting a top lid thus formed in the upper track of the chest frame. 2. A method as claimed in claim 1 wherein the runner is inserted into a runner receiving slot of the edging strip. 3. A method as claimed in claim 1 including the step of bonding a handle to the edging strip of the curved lid. 4. A method as claimed in claim 3 wherein the handle includes a handle grip part and a mounting part and the method includes the steps of:- inserting the handle grip part in a recess of a jig; applying adhesive to the exposed mounting part of the handle; mounting the edging strip of the curved lid to the adhesive on the handle mounting part; and clamping the lid to the handle. 5. A method as claimed in claim 4 wherein the lid is clamped to the handle by a clamping means which is released automatically after a preset time. 6. A method as claimed in claim 5 wherein the runner is applied to the edging strip when the clamping means is operated. 7. A method as claimed in any preceding claim wherein the chest frame members are moulded parts having formations which interengage with one another on assembly. 8. A method as claimed in claim 7 wherein the method includes the step of ultrasonicaily welding the chest frame members together on assembly. 9. A method as claimed in claim 7 or 8 wherein, after assembly, a sealant and an adhesive are applied to the joints between the chest frame members prior to insertion of the liner and the outer cabinet body. 10. A method as claimed in claim 9 wherein the sealant includes a foil strip applied over the joints and the adhesive is a hot melt adhesive which melts on moulding of the insulating core. 11. A method as claimed in any preceding claim including the step of inserting runners in at least the front frame member of the chest frame. 12. A method as claimed in claim 11 wherein runners associated with the lower lid and top lid are inserted in the front frame member of the chest frame. - 14 - 13. A method as claimed in any preceding claim wherein the or each runner is of wear resistant plastics material and the or each runner is snap fittingly engaged with a corresponding recess in the lid edging strip or chest frame member. 14. A method as claimed in any preceding claim wherein the lid edging strip is cut to a desired length and subsequently four V-notches are cut from the lid edging strip at locations to correspond with the corners of the curved pane. 15. A method as claimed in any preceding claim including the steps of:- turning the cabinet formed on insertion of the inner liner and outer cabinet body to the chest frame so that an open lid-receiving side of the cabinet is lowermost; lowering the open side of the cabinet onto an inner mould part; closing an outer mould part around the cabinet; and, after injection of the liquid foam reactants, curing the foam; the mould being moved during filling and/or curing so that the insulating foam fills the cavity. 16. A method as claimed in claim 15 wherein the mould is moved by moving the mould about a longitudinal or transverse axis of rotation with respect to a mounting bed in which the mould is mounted. 17. A method for manufacturing a sliding curved lid refrigerated merchandising unit substantially as hereinbefore described with reference to the accompanying drawings. 18. A sliding curved lid refrigerated merchandising unit whenever manufactured by a method as claimed in any preceding claim.

Inventors: POWER PAUL, POWER, PAUL
Applicants: ORRELL LTD, POWER PAUL, ORRELL LIMITED, POWER, PAUL
Application year: 1996
Main classification: F25D23
IPC codes: A47F3, F25D23