NZ246006A - Method for producing a supermarket trolley using synthetic material - Google Patents

Abstract

A method for producing a trolley made of a synthetic material, particularly a supermarket trolley comprising a leg (43) and a basket (3), wherein at least two trolley portions (1, 3) are first moulded, then assembled. Each side wall (1, 3), which is provided with flanges (12, 13), and a leg segment (2, 3) linked to said side wall (1,3), are integrally moulded. Said side walls (1, 3) are then joined with connecting elements (23) which fit inside said flanges (12, 13).

Description

New Zealand No. international No. 24v5006 j Priority Dats(s): ^ i j ^omP*'"5,9 Specificaiion Fi?Gd; ..4)>|cte . 'aos: ;I ;> ;:> b''C3t»on Dai3:...A.S. '"•■3. -Journal No: .'.HrPlS' ;NEW ZcALAND PATENTS ACT 1953 complete specification ;Title of Invention: ;Method for producing a trolley made of a synthetic material ;Name, address and nationality of applicant(s) as in international application form: -jgo 34_ ;GIAT INDUSTRIES, a French company of 13 Route de ia Miniere, ?8000 Versailles, France; I.C.D. HOLDING, a Dutch company of Teteringsedijk 89 H NL 4817 MB Breda, The Netherlands ;I. fby poi0i£ \.C{ ;246006 ;Method for Manufacturing a Trolley from Synthetic Material ;The present invention relates to a method for manufacturing a trolley from synthetic material, in particular a trolley for use in self-service stores, said trolley having a first flank and a second flank, each of which includes a foot part and a basket part, both moulded as a single piece, said first and second flanks being mutually connected by means of coupling elements. ;Such a manufacturing method is disclosed in US Patent No. 3,614,133. The known trolley is made from two identical flanks. The basket part of each flank consists of an arm which extends upwards from the foot part to where the handle is situated. The foot part is configured like a hair-pin reinforced by a central support. A first mesh is mounted on the upper arm of the hairpin configuration, which mesh is also secured to the basket part. The first meshes mounted on the flanks are mutually connected by means of second meshes forming the front and back of the basket. The different components are assembled by means of threaded bars and nuts. ;A drawback of the trolley obtained through the known method consists in that a large portion of the basket is overhanging, ;said portion being only supported by the upper arm of said hairpin configuration. This same arm has also to support the first mesh. This construction, added to the fact that the first mesh is moreover connected to an upper point on the basket part, does not ensure sufficient stability for the trolley and may cause the trolley to topple over forwards when too much weight is placed on the front portion of the trolley. In order to solve this problem, the known trolley comprises a central support. However, the presence of this central support limits the nesting of the trolleys inside one another, which in its turn requires a larger storage area for the trolley park. ;An object of the invention is to provide a method for manufacturing a trolley having greater stability without limiting the nesting possibilities. . ' ;N.Z. PATENT office ;25 JUL 1996 * ■ received 2 24Q00G To this end, a method according to the invention is characterized in that, when moulding the flanks, at least the lateral perimeter of each basket part as well as a first flange on the first flank and a second flange on the second flank are moulded as a single piece, said first and second flanges being moulded so as to project in opposite directions when the trolley is assembled, said first flank and said second flank being assembled by means of coupling elements which are attached to said flanges. Since at least the lateral perimeter of the basket part and a flange are moulded so as to form a single piece with the flank of the trolley, a more rigid flank structure is obtained. This more rigid structure makes it possible to absorb better the forces exerted by the objects placed in the basket and therefore to make the trolley more stable. In view of the fact that the lateral perimeter of the basket part is an integral part of the flank, a force exerted even on the forward portion of the basket is distributed over the entire trolley. In this way, a better equilibrium of the trolley is obtained, without requiring the use of reinforcement elements which restrict nesting. The presence of the flanges not only makes it possible to stiffen the trolley structure but offers also an appropriate means of quick and reliable assembly.

Moreover, since the flank and the foot part form a single unit, it is possible due to the geometry of this unit to considerably reduce deflection thanks to the fact that the flank-foot unit is moulded as a single piece; it is also possible to use moulds whose cavity is smalJ. at least as to the depth thereof. The use of coupling elements which are attached to the flanges aUow the use of the same size of flank and therefore the same mould for obtaining different sizes of trolley. Since these coupling elements are simple to manufacture and do not require deep-cavity moulds, their use makes it possible to reduce considerably the investment in moulds and therefore the manufacturing costs. The particular and judicious choice in the manufacture of the different components of the trolley makes it possible therefore not only to make a stronger and sturdier trolley but also to manufacture it at a substantially reduced "I cost. nTz patent ofricej 2 5 JUL 1395 i 3 246006 A first preferred embodiment of the method according to the invention is characterized in that the flanks are moulded to a given size, a set of coupling elements being moulded for each flank size, with the different elements of said set having each a mutually different predetermined width. This allows modular construction of the trolley. Starting from one and the same flank size, trolleys of different capacities can be thus constructed simply by using coupling elements of different widths. The production cost for trolleys of different volumes is therefore reduced in this way.

A second preferred embodiment of the method according to the invention is characterized in that at least one opening is moulded in the basket part of each flank. Thanks to the moulding technique used for the flanks, it is possible to easily make an opening therein, since the pressing is performed perpendicularly to the plane of the flank. Without having to use moulds which are expensive to manufacture, it is possible in this way to make openings in the flanks at reduced cost, without affecting the rigidity of the trolley.

Preferably, a mesh is attached in each of said openings. This gives a well known appearance to the trolley.

Preferably, two essentially triangular openings are provided in each flank, said openings being separated by a brace which extends diagonally in said flank from an upper forward portion of the trolley towards a lower rearward portion thereof. The presence of the diagonal brace provides further stiffening of the trolley.

A third preferred embodiment of the method according to the invention is characterized in that at least one attachment point for a handle is moulded simultaneously with the moulding of said flank. These attachment points thus form a single piece with the flank, which makes the manufacture easier and makes it possible to achieve rigid attachment.

A fourth preferred embodiment of the method according to the invention is characterized in that a flap provided- with a n.z. patent office JUL 1996 Deceived 246006 projection whose length corresponds to the distance between the bosses is mounted against the gate in such a manner that the bosses and the projection form a hinge. This makes it possible to ensure good attachment of the flap to the trolley, which flap can serve then as a child-seat.

A fifth preferred embodiment of the method according to the invention is characterized in that a guide rail is moulded onto each flank, underneath the bottom of the basket, and in that after having assembled the first and second flanks, a sliding panel is mounted between the guide rails. In this way, the panel can slide in the rails and makes it possible to place objects % thereon without having to lift them too high, which is especially an advantage with haavy objects and which makes the use of such a trolley more attractive for persons having some difficulty in lifting such objects.

Preferably, another opening is made in the coupling element for mutually connecting the first and the second flanks at their fronts , an extraction tongue being mounted on a transverse edge of said opening. This makes it possible to introduce easily an advertisement panel in or in front of said other opening.

Preferably, the elements of the trolley are made of SMC (Sheet Moulding Compound). SMC is a light material which has good shock resistance, which makes it perfectly appropriate for manufacturing the trolley.

The invention will now be described in more detail with the help of the drawings, which illustrate examples of a trolley manufactured by the method according to the invention.

In the drawings: Figure 1 is an exploded view of an example of a trolley manufactured by the method according to the invention.

Figure 2 illustrates in detail a flank of a trolley according to the invention.

Figure 3 shows another example, also as an exploded view, of a trolley according to the invention.

N.Z. PATENT"OmCEj 2 5 JUL r:% ! 246006 Figure 4 illustrates a detail of a gate provided with a flap.

Figure 5 illustrates the mounting of a sliding panel on a trolley according to the invention.

Figure 6 shows the application of an advertisement panel to a trolley according to the invention.

Figure 7 illustrates part of the advertisement panel.

In the drawings, the same or similar elements have been given the same reference number.

The synthetic material from which the trolley is made is preferably SMC (Sheet Moulding Compound). This synthetic material is used, among other things, for manufacturing automobile bumpers and has the advantage of being very resistant to shocks, easy to mould and not very expensive. Moreover, this material is practically fully recyclable. The different components of the trolley are preferably compression moulded, but of course other manufacturing techniques are also applicable. Besides the composite SMG, other synthetic materials, such as for example epoxy reinforced wi?.:-« glass fibres, can be used.

Figure 1 shows an exploded view of a first example of a trolley manufactured by the method according to the invention. The trolley comprises a first flank 1 and a second flank 3. Each flank includes a flange 12, 13, which extends over the entire perimeter of the cavity of the basket. The flange 12 on the first flank 1 and the flange 13 of the second flank 2 are moulded in such a manner that they project in opposite directions when the trolley is assembled. The foot of the trolley comprises two parts 2, 4 each of which is integral with its respective flank. As illustrated in detail in Figure 2, the foot part 2 and the flank 1 are moulded as a single piece.

Thanks to this, a very rigid connection is obtained between the foot part 2 and the flank 1.

The foot part 2 includes a first portion 19, a second portion , and a third portion 21 whir?h arp mnnlflarl nji a single piece.

[N~z. patent uglce L JUL 1996 "recbvedT 246006 The first portion 19 shows substantially a hair-pin geometry, which allows good absorption of the deflection imposed by the basket when it is filled. The inclination of the second portion 20 as well as the inclination of the bottom of the basket makes it possible to nest the trolleys when they are stored. The third portion 21 forms a flange which serves for assembling the different parts, as explained hereinafter.

As mentioned hereinabove, the foot part and the flank are moulded as a single piece. As can be seen in figures 1 and 2, 10 the thickness of the flank, of its flange, and of the foot part is not great. This makes it possible to use for moulding the components of the part a shallow mould (stamp/die), for example 150 mm. Such moulds are substantially less expensive than deep moulds. During moulding, the compression is exerted in a direction which is perpendicular (flat moulding) to the plane defined by the flank. In this way, the compression does not require a large displacement of the stamp, and will lead to a higher production rate and therefore less expensive production.

As the flanks are flat moulded, it is now possible during 20 moulding to provide openings 8 and 9 in the flank of the basket, making it possible to look from the outside into the inside of the basket. It will be clear that the number of openings shown (two) is only one choice and that other alternatives can also be considered. Preferably, a mesh 10, 11 is mounted in the openings 8, 9. These meshes are preferably manufactured by moulding from the same material as the flank. They can be moulded either simultaneously with the flank or separately and glued thereafter into the openings. The use of meshes gives in this way a well-known appearance to the trolley. But it will be clear that the 30 meshes can also be made from other materials than the one used for the flank, such as for example from injected ABS.

Preferably, the openings 8 and 9 are separated by a brace 47 which runs diagonally in said flank. The brace.47 runs from the bottom of the basket on the rearward side of the trolley to an upper forward portion. The width of the brace preferably increases in the direction of the bottom of the basket. The presence of this brace makes i|6T^^ii?ie-Bot—only to define 'OFFICE! JUL 1996 RECEIVED 246 00 6 partially the perimeter of the openings 8 and 9, but also to stiffen the flank. Of course, the brace 47 is moulded as a single piece with the flank.

Each flank is provided with an attachment point 5, also moulded as a single piece with the flank to which it is adjoined. This attachment point serves to attach thereon a handle 6, for example by means of a bolt 7 or by gluing the handle to the attachment point.

Each foot part is provided with small wheels 14, 15 affixed by 10 means of appropriate attachment members 16, 17 to the lower portion of the foot as illustrated in figure 2.

Each flank preferably also includes a recess 18.

This recess serves for housing therein a projection 14 on a.gate 40 of the trolley.

The gate is preferably also provided with openings wherein meshes 41 are attached. Thanks to the use of the projection 14 and the recess 18, the gate can pivot towards the inside of the basket so as to permit the trolleys to be nested within one another. Preferably, an exchangable piece 42 is slid over each 20 projection 14 when mounting the gate. The use of this exchangable piece makes it possible to reduce the friction of the projection within the recess.

The third portions 21 of foot parts 2 and 4 are mutually connected by means of a skirt 43 which engages in these third portions. The skirt 43 is preferably glued to the first portions 19. This skirt is preferably also manufactured by moulding, like the other components of the trolley.

The flanges 12 and 13 of the flanks are connected by a bottom beam 39, which has preferably a T-shape, making it possible in 30 this way to attach the mesh to the bottom of the basket. The bottom beam 39 is preferably glued to the flanges 12 and 13.

The forward extremities of the second portions 20 of the foot parts are mutually connected by means of another beam 22 which engages in these extremities anch ied therein.

JUL 1996 RECEIVED 8 246006 v The front portion of the basket is composed of a coupling element 23 which is preferably provided with an opening 24 destined for receiving an advertisement panel. The handle 6 is preferably mounted when the other components of the trolley have been assembled.

The technique used for manufacturing and assembling the trolley makes it possible now to manufacture trolleys of different volumes starting from flanks of the same size. Obtaining the desired volume is achieved by the width of the coupling elements 43, 39, 22 and 23. In this way, it is for example possible, starting from flanks of the same size, to manufacture trolleys the volumes of which range between 45 and 80 litres. When starting for example with a set of four different sizes of flanks, the following volumes can be obtained : series 1 : 45 - 60 - 80 litres series 2 : 80 - 100 - 125 litres series 3 : 120 - 150 - 180 litres series 4 : 180 - 200 - 230 litres.

Consequently, it is possible to obtain a large variety of sizes of trolley while having a limited number of moulds. This makes it possible to manufacture cheaply trolleys of different volumetric capacities since the investment in moulds is not high. The described technique makes it possible to use a specific flank-size "Step" per series, the width being determined by the basket section. The coupling elements are then manufactured as a function of this "Step", which gives the advantage of standardization of these moulds. The use of a "Step" is illustrated by means of Table I below which indicates for the trolleys of series 3, the different widths of the coupling elements. As can be seen from this Table I, the width increases each time by 28 mm when the volume increases by 10 1. n.z. patent office Ed JUL 1996 received 246006 TABLE 1 VOLUME EXTERNAL WIDTH ± 5 % in mm 120 I 424 130 I 452 140 I 480 150 / 508 160 I 536 170 I 564 180 / 592 Thanks to the use of the flanges 12 and 13 on the flanks and also on the foot part 44, it is possible for the coupling elements to be fitted into these flanges. By reducing the thickness of the material at the flanges, it is possible to apply the components thereto in such a manner that a flush joint is obtained.

Besides the above-mentioned standard sizes, it is also possible to manufacture intermediate sizes related to the above-described 10 "step", for example by cutting portions from the coupling elements. Of course, a minimum width has to be respected so as to assure the sideways stability of the trolley.

Figure 3 shows another example of a trolley according to the invention. In this example, the flanks are assembled by means of coupling elements 25 and 2 6 which are integral with the flank. As a matter of fact, for these trolleys, such as those of series 1, the width of the basket is too small to justify the use of intermediate elements. Even the moulding of one half of a trolley as a single piece does not require a mould of a great 20 depth.

Figure 4 illustrates a particular embodiment of a gate 40 for a trolley according to the invention, numerous tmi Tayg are JUL 1996 received 246006 equipped with a child seat fitted to the gate of the trolley.

This option is also applicable to a trolley according to the invention. When the gate is provided with the phild-seat option, two bosses 27 and 28 are provided, one on each side of a median line of the gate. The bosses are situated on one edge of the gate, which edge is situated near the bottom of the basket. A flap 29 provided with a projection 30 is mounted on the gate 40 in such a manner that the projection 30 is lying between the bosses. To achieve this, the projection 30 is of a length which corresponds to the distance between the bosses 27 and 28. The projection-boss unit then forms a hinge permitting the flap 29 to be pivoted with respect to the gate and to form in this way a child seat. Preferably, the bosses are each provided, on one of their ends, with a recessed surface and are disposed in such a manner that the recessed surfaces are facing one another. The projection is then provided with bulging ends destined to engage in the recessed surfaces. This makes it possible to achieve good attachment of the projection to the bosses. The use of the bosses makes it possible to increase the safety of the seat by relieving the load on the rotation axis of the flap.

Figure 5 illustrates a detail of another example of a trolley according to the invention. In this example, a guide rail 31 is applied to the flank 1 underneath the bottom of the basket. The guide rail is preferably moulded separately and then glued or screwed to the flank. A sliding panel 32 is mounted between the guide rails of each of the flanks. The forward end of the guide rail is provided with a stop, preventing the panel from sliding towards the front of the trolley and causing too great a deflection of the foot. The panel slides towards the back of the trolley and passes between the two parts of the foot above the skirt 43. The presence of this sliding panel is made possible by the use of two foot parts. Indeed, since the foot comprises two parts mutually connected by a skirt, it is possible to leave an opening between the bottom of the basket and the upper edge of the skirt. The panel 32 then slides through this opening.

The presence of such a panel makes it possible to place thereon large objects which are difficult to lift. As the panel is n.z. patent office B 5 JUL 1996 received " ii 24 6 0 0 6 v situated underneath the basket, the object does not have to be lifted above the basket, which reduces considerably the effort required of the user.

Figure 6 illustrates a sectional view of the front panel 23 of the trolley. This front panel comprises an opening 24 for receiving an advertisement panel 34 therein. Thanks to this opening, the advertisement panel can be seen from both sides of the front panel. The panel 34 is housed in a frame 33 situated on at least part of the perimeter of the opening 24. The frame is either directly moulded on the front panel, or mounted afterwards onto this front p^nel, for example by means of small diametrically opposed projections 45. In the latter case, corresponding holes are made in the front panel during moulding. The frame includes preferably a transparent protective sheet 37 and a tongue 36 for hanging the panel 34. An extraction tool 35 makes it possible to remove the advertisement panel housed in the frame. As illustrated in figure 7, the tongue 36 is housed in a recess 46 provided in the frame 33. For replacing the advertisement panel, the tool 35 has only to be applied underneath the tongue and the panel released. The new advertisement panel is then inserted into the frams and fixed in place by the tongue. This is done in a simple and q'lick operation.

Trolleys made from synthetic material have the advantage that they do not disturb the electromagnetic waves used by anti-theft detectors, which is not the case with metal trolleys. Thanks to the method of the invention, which makes it possible to manufacture at favourable cost a trolley made of synthetic material, the replacement of metal trolleys by these synthetic trolleys will become more attractive from an economic point of view and this will therefore also allow the use of anti-theft detectors using electromagnetic waves for verifying whether all the objects in the trolleys have indeed been paid for.

The method according to the invention can be used for manufacturing all types of trolleys for use in self-service stores. The method can be used in this way for manufacturing trolleys having a basket either of a large or a small depth.

N.Z. PATENT OFFICE JUL 1996 RicilVED 12 24 6 0 0 6

Claims (14)

claims

1. A method for manufacturing a trolley from synthetic material, in particular a trolley for use in self-service stores, said trolley having first and second flanks, each including a foot part and a basket part, each flank being moulded as a single piece, said first and second flanks being mutually connected by means of coupling elements, characterized in that, when moulding the flanks, at least the lateral perimeter of the basket part and a flange 10 are moulded as one piece on each flank, the flanges being respectively a first flange on the first and a second flange on the second flank, said first and second flanges being moulded so as to project in opposite directions when the trolley is assembled, and said first and second flanges being assembled by means of coupling elements which are attached to said flanges.

2. A manufacturing method according to claim 1, characterized in that the flanks are moulded in a predetermined size, a set of coupling elements being moulded for each size of flank, the 20 different elements of said set having each a mutually different predetermined width.

3. A manufacturing method according to claim 1 or 2, characterized in that at least one opening is moulded in the basket part of each flank.

4. A nanufacturing method according to claim 3,; characterized in that two substantially triangular openings are provided in each flank, said openings being separated by a brace which extends diagonally in said flank from an upper forward portion of the trolley to a lower rearward portion thereof. 30

5. A manufacturing method according to claim 3 or 4, characterized in that a mesh is attached in each of said openings.

6. A manufacturing method according to any one of claims 1 to

5. characterized in that at least one attachment point for a n.z. patenfofrce 2 5 JUL 1995 received" i3 24 6 0 0 6 •*;handle is moulded simultaneously with the moulding of each flank.;7. A manufacturing method according to any one of claims 1 to 6, characterized in that a gate provided with two bosses,;one on each side of a median -line of the gate and situated at one edge of this gate at the level of the bottom of the basket, is mounted on a rear edgeof the trolley.;

8. A manufacturing method according to claim 7, characterized in that a flap provided with a projection whose length corresponds to the distance between the bosses is mounted against the gate in such a manner that the bosses and the projection together form a hinge.;

9. A manufacturing method according to any one of claims 1 to 8, characterized in that a guide rail (31) is moulded onto each flank underneath the bottom of the basket.;

10. A manufacturing method according to claim 9, characterized in that after haying assembled the first and second flanks, a sliding panel is mounted between and*within the guide rails.

11. A manufacturing method according to any one of claims 1 to 10, characterized in that another opening is made in the coupling element for mutually connecting the first and second flanks at their forward part, an extraction tongue being mounted on a transverse edge of said,other opening.

12. A manufacturing method according to claim 11, characterized in that a frame is applied to at least a portion of the • perimeter of the other opening when moulding the coupling element.

13. A manufacturing method according to any one of claims 1 to 12, characterized in that the elements of the trolley are made of Sheet Moulding Compound.

14. A manufacturing method as claimed in any one of the preceding claims substantially as herein described with reference to the accompanying drawings. n.z. patent officfc ?.5 JUL 1998