WO1992002160A1

WO1992002160A1 - A catering cart

Info

Publication number: WO1992002160A1
Application number: PCT/DK1991/000226
Authority: WO
Inventors: Johannes Blücher SKILBILD
Original assignee: Johannes Blücher Skibild, Metal A/S
Priority date: 1990-08-10
Filing date: 1991-08-12
Publication date: 1992-02-20
Also published as: AU8392991A; DK191190D0

Abstract

A catering cart (20) with driving wheels (13) comprises at least one storage (12, 12') for trays (1) mounted in a raising/lowering system arranged in opposite side walls (18) of the cart, said system having at either side a plurality of carrier members (2) equipped with carrier brackets (3) for the trays (1), the trays being successively retractable from and insertable into the upper end of the cart. The carrier members are piled in a vertical row or channel (14) communicating with an upper store space (10), in which the carrier members can be laterally introduced and collected. The carrier members (2) are displaced vertically by means of a motor driven (9, 9') worm spindle (8) which engages the lower one (7) of the carrier members.

Description

A catering cart

The present invention relates to a catering cart having a cart body for receiving catering trays in at least one pile, and of the type provided with a raising and lowering mechanism operable to successively raise and lower the pile for elevating the trays to an upper delivery position, respectively lowering the pile step- wise for enabling the cart to be filled by used return trays loaded successively from above.

Conventional catering carts as used e.g. in passen¬ ger airplanes are designed in a simpler manner just with a fixed rack or bracket system for receiving the trays, which are thus taken out from and inserted into the respective different levels in the cart body. It is easy to use the uppermost levels, but for the attendants it causes considerable physical stress to use the lower levels, and this is even psychically stressing because the attendant, in her or his associated bent-down posi¬ tion, is no longer able to keep a steady eye contact or control with the surroundings. These problems have been very well known for a long time and they are considered decidedly serious, but despite previously proposed solu¬ tions no such solution has been provided which has been found usable in practice.

The principal solution of the problem, of course, will be to arrange for the trays to be successively elevated into an upper delivery position as they are successively removed therefrom, and, respectively, to be successively lowered from this upper position when they are supplied thereto as return trays, whereby all de¬ livery and loading can take place at the upper end of the cart body. Thereby the said problems will be effec- tively overcome, but evidently an associated practical solution should have to be suitable also in other re¬ spects, and just at this point the prior art proposals have exhibited substantial drawbacks, which are now overcome by the present invention.

Thus, US-A-3,104,141 discloses a catering cart of the relevant type in which a raising/lowering mechanism is a tackle system that is operable for raising and lowering of a lower carrier plate for the pile of trays. This could be a good solution if the trays are pilable directly on each other, but normally this is not the case, because the tray edges project only slightly up¬ wardly, while some of the objects placed on the trays are still higher. According to the said known proposal, therefore, it is prescribed that the single trays are provided with upstanding spacer or handle portions, such that each tray can be supported by the underlying tray suitably spaced therefrom, but the use of such notice¬ ably upstanding parts on the trays themselves has been found unacceptable in practice, and for this and other reasons the discussed problem has simply not been solved.

It could be an obvious possibility to make use of a system of carrier chains provided with inwardly protrud¬ ing and mutually correctly spaced carrier brackets, but with such an arrangement there are considerable problems in arranging the return run of the chains in a way such that the brackets do not cause troubles during their return run.

According to the present invention it is realized that it is perfectly possible to make use of carrying distance pieces between the trays, when only these pieces belong to a separate moving system arranged in¬ ternally in the cart. Each of these distance pieces may have inwardly protruding bracket means for carrying the trays, and the columns of distance pieces resting on each other may then be displaced upwardly and downwardly by a. raising and lowering of lowermost carrier means corresponding to the said carrier plate of the proposed known device. A problem will remain, viz. that the distance pieces at the top of the cart will be pushed further upwardly when trays are successively elevated to and removed from the said upper delivery position, and already hereby not either such a solution could be us¬ able in practice, because upstanding magazine portions should be used for taking up the distance pieces dis¬ placed upwardly from the cart body.

According to the invention, however, this drawback is overcome by the recognition that the carrying dis¬ tance pieces may be guided in guide portions of the cart in a manner such that once they have been elevated to the upper delivery level for the respective trays they are guided laterally outwardly in response to a further raising of the pile of distance pieces, such that they retreat into a magazine compartment, which will not need to project above the natural top of the cart. The dis¬ tance pieces, moreover, may be coupled together in such a manner that by a lowering of the pile they will be successively pulled in from their laterally stored posi¬ tion to a position on the top of the pile, whereby the these distance pieces may successively receive return trays for lowering the same into the cart body.

Accordingly, the invention is characterized by the features specified in the characterizing clause of claim 1.

Thus, with the invention it is possible to make use of trays of a quite ordinary, low type in connection with a cart of a normal appearance, and the invention does not imply side effects that could disqualify it in practice.

Suitably the said piles of carrier pieces having inwardly protruding carrier brackets may be arranged adjacent the corners of the piled trays. These piles with their associated storage compartments need not taking up space in the more critical width dimension of the cart, as they can very well be located at the re¬ spective front and rear ends of the cart. For other' reasons, e.g. for enabling a collective loading or re¬ moval of the entire pile of trays, it may be desirable that the full front area and optionally the full rear cart body area are accessible, as this or these areas may be covered by openable doors, such that the carrier piles and their associated storage compartments are more suitably arranged at the lateral sides of the cart, even though this might cause. an increase of the critical total width of the cart. Alternatively it may have to be accepted that the trays in use should have a slightly reduced width, but it is worth mentioning that in con¬ nection with the invention it has already been found possible to incorporate the raising/lowering system in catering carts with conventional widths of both the carts and the trays.

In the following the invention is described in more detail with reference to the drawings, in which

Fig. 1 is a perspective view of a catering cart according to the invention, shown partly as an X-ray view,

Fig. 2 is a perspective view of a single carrier member therein,

Figs. 3, 4 and 5 are lateral sectional and partial views of two intercoupled carrier members,

Figs. 6, 7 and 8 are plan views of a series of such carrier members, and

Fig. 9 is a schematic view of a modified raising/- lowering system in the cart.

In fig. l is shown a catering cart 20 built up on a wheel supported lower part, which holds the majority of the technical installation and is provided with carrying side walls 18, in which the raising/lowering system is integrated, and a top portion having two handles 21 making the cart operable from both sides.

Inside the cart there is provided two storage com¬ partments 12,12', each holding a pile of trays 1, each tray being carried on brackets 3 protruding into the compartment from individual, rod shaped carrier members 2, such that each carrier member 2 with its associated bracket 3 serves to carry one tray. At each side of each compartment there is arranged two vertical rows of car¬ rier members, the design and function of which will be described below.

As shown in Fig. 2 each carrier member 2 consists of an elongated body, preferably of a rectangular cross section, having slots 5 located at opposite sides and extending from respective opposite ends at least halfway and preferably somewhat more than halfway along the length of the body. Each of the bodies has a central, throughpassage 6 communicating with the slots 5. Between the rod-like bodies are arranged connector members 4 coupling the bodies together into a flexible column or chain. Each connector member 4 is of an elongated shape and is provided with a head portion 19 at either end, these portions fitting loosely in the passages 6. The ends of the bodies are cut at an oblique angle, prefer¬ ably at some 15°, and at either end there is an internal thickening 11, which prevent the connector members 4 from being retractable. As shown in Figs. 3-5 the con¬ nector members may project from the members 2 both end¬ wise and sidewise through the slots 5.

In each of the side walls 18 of the cart there is provided an integrated guiding track 18' for the carrier members, optionally with an additional guiding rail 14, the track at the top continuing into a storage compart¬ ment 10, in which the carrier members can be stored side by side as shown in Figs. 1 and 8. The side walls 18 are made as sandwich structures that are strong, stiff and fireproof, e.g. based on a glass or carbon fibre rein¬ forced phenol resin.

At the middle of each storage compartment 10 there is a vertical plate 30, from which there extends to either side a weak compression spring 31 having at each free end a shoe plate abutting the side of the innermost carrier member 2 in the store to thereby stabilize this member in a vertical position.

The lowermost carrier member in each pile is car¬ ried by a support member 7, which is in screw engagement with a vertical spindle 8. By means of a flexible shaft each spindle 8 is in driving connection with an electro¬ motor 9 or 9', viz. one motor for each tray compartment. The motors are energized from a rechargeable battery 16, and the electrical equipment of the cart is controlled by a control unit 17, all mounted, as shown, in the bottom region of the cart.

The connector members 4 are inactive when the car¬ rier members 2 rest on each other. The purpose of the connector members is to ensure that all carrier members will return in a correct manner from their stored con¬ dition by establishing a pulling connection between these members, and to ensure that the carrier members are correctly introduced into the store and arranged side by side therein.

When the support members 7 assume their bottom positions the tray store 12 can hold a maximum of trays. The entire set of trays may well be introduced simul¬ taneously through an open or openable side of the cart. For a full pile height of the carrier members there will be present at the top end an extra number of such mem¬ bers, which fill out most of the illustrated curved transitions between the guiding tracks 18' and the stor¬ age compartments 10, this with the described embodiment being important for securing a safe introduction of the uppermost carrier members of the piles into the compart¬ ments 10.

When the uppermost tray is drawn out through the opening 15 this will be detected by a non-illustrated sensor, which will actuate the motor 9 so as to cause a raising of the pile until the next tray comes up to the opening 15. Hereby, as shown in Fig. 6, the uppermost carrier member 2b in each pile will be pushed upwardly against a curved ceiling portion 10a of the storage compartment 10, whereby the upper end of that carrier member is guided slightly towards the right, so as to cause the preceding members 2 to be pushed slightly into the storage compartment. At the same time the pressure between the interabutting, obliquely cut ends of the carrier members 2a and 2b will show the effect of the lower end of the member 2b being displaced to the right, this being enabled by the associated inwardly directed curving 10b of the guiding track 18' in a floor surface 10c of the storage 10.

When the member 2b is forced upwardly some of the preceding members including the member 2c will be pressed into a slightly oblique position, such that at the lower end of the member 2c there will be provided room sufficient for the lateral displacement of the lower end of the member 2b to take place without any substantial counter pressure, irrespectively of the effect of the spring 31. On the other hand, this spring will serve to generally hold the carrier members in the store oriented vertically, whereby the guiding of the carrier members upwardly and outwardly into the storage compartments can take place in a well stabilized and easy manner.

When the lower end of the member 2b has been almost entirely displaced from the member 2a these members will meet along rounded corner portions, whereby a safe final displacement of the member 2b will be achieved in that the upper end of the member 2a, when forced further upwardly, will press out the lower end of the member 2b with increased force. Thereafter (Fig. 8) the raising procedure can be repeated.

The inclination of the end faces of the carrier members should be kept as small as possible ; of course it should be sufficient to secure the desired sliding off adjacent the storagecompartment, but if it is chosen larger than required an associated wedge function lower down in the guiding track 18' may give rise to consider¬ able clamping problems.

The electrical control system 17 of the raising/- lowering system, as mentioned, may be adapted such that by a removal of trays an upward displacement of the pile of trays will take place automatically in response to the uppermost tray being taken out. In a similar manner the control unit may be laid out so as to cause the system to move a step downwardly as soon as a tray has been inserted in the uppermost position, this being actual when the cart is filled by either used trays, after the serving thereof, or when the cart is filled with new, ready-to-serve trays, if these are not in¬ serted from the front of the cart. By an associated downlet the connector members 4,19 will ensure a succes¬ sive outwardly and downwardly guiding of the carrier members from the upper storage^"compartments.

Optionally the control of both the raising and the lowering can be effected by means of operation buttons 22 mounted e.g. on the handle members 21.

In Fig. 9 is shown a modified embodiment, in which the brackets 3 are mounted on carrier links of a chain 35, which passes over an upper chain wheel 36 between an operative, hanging length B and a upper, horizontal storage length M. The hanging, bracket carrying chain links are stabilized in the guiding track 18', while the links when introduced into the storage compartment are collected on a non-illustrated carrier rail, which sup¬ ports the brackets 3 and permits the remaining chain links to hang down in loops between the bracket links as here closely juxtaposed. The chain wheel is driven through a self blocking drive system 37. It will be appreciated that also in this manner it can be ensured that the upper, unused bracket carriers can be stored such that they will not give rise to problems by any return movement in the vertical direction.

Claims

C L I M S

1. A catering cart having a box-shaped body for receiving catering trays in at least one pile, and ^'of the type provided with a raising and lowering mechanism operable to successively raise and lower the pile for elevating the trays to an upper delivery position, re¬ spectively lowering the pile stepwise for enabling the cart to be filled by used return trays loaded succes¬ sively from above, characterized in that the raising/- lowering mechanism comprises respective piles of indivi¬ dual carrier and distance elements having a height cor¬ responding to a desired mutual distance between the trays in the pile and provided with tray carrier brackets protruding into the space of the cart body, said piles of distance elements being supported by sup¬ porting means connected with means for vertically moving these element up and down through the effective height of the cart, whereas the distance elements at the upper end of the cart body are adapted to cooperate with a storage unit, which, in response to each distance ele¬ ment being moved upwardly into and further beyond the delivery position, affects the relevant upper distance element to be laterally displaced from the pile of these elements, such that the distance elements elevated to said delivery position and therebeyond will be succes¬ sively collected in the storage unit at a level located only shortly above the delivery position of the trays.

2. A catering cart according to claim 1, in which the raising/lowering mechanism comprises a vertical screw spindle, characterized in that the screw spindle is in a direct drive engagement with the said supporting means for each of the piles.

3. A catering cart according to claim 1, charac¬ terized in that the distance elements are coupled to¬ gether such that upon their being raised to the delivery position they are laterally displaceable from each other along a guiding surface of the storage unit, the dis¬ tance elements hereby also being intercoupled such that by a lowering of the pile they are automatically succes¬ sively retracted from the storage for a subsequent down- let in the pile of these elements.

4. A catering cart according to claim 3, charac¬ terized in that the distance elements in each pile are at least at one end cut along a plane, which, seen in a direction laterally towards the storage for the par¬ ticular pile, is sloping downwardly, preferably at an angle of approximately 15° with the horizontal plane.

5. A catering cart according to claim 3, charac¬ terized in that the distance elements are coupled to¬ gether by means of loose coupling pieces, of which oppo¬ site widened head portions are received in axial pas¬ sages in the opposed distance elements, the coupling pieces extending between these elements through inter¬ facing, axially oriented slots in the respective halves of the distance elements, or, respectively, through outermost narrowed end portions of the said axial pas¬ sages when the distance elements stand on each other in the pile configuration.

6. A catering cart according to claim 3, in which the carrier brackets are only shortly projecting from from the said carrier or distance elements, these being arranged pilewise adjacent the respective four corners of the trays, preferably outside respective innermost wall portions, in which there are provided vertical slots for accommodating the inwardly projecting support brackets .

7. A catering cart according to claim 4 and com¬ prising two piles of trays and a central raising/lower¬ ing mechanism arranged in a hollow middle wall portion of the cart, characterized in that the cart is provided with individual raising/lowering mechanisms for the two or more tray piles as arranged side by side or in front of each other.

8. A catering cart according to claim 1, in which the raising/lowering mechanism for interrelated piles of carrier or distance elements are connected to a driving electromotor mounted in the cart together with a re¬ chargeable battery likewise mounted in the cart.

9. In a catering cart according to claim 1 the modification that the raising/lowering mechanism com¬ prises carrier chains hanging down from upper chain wheels and provided with said inwardly protruding car¬ rier brackets, whereas the chains extend from the top sides of the chain wheels into storage means, which, when the carrying chain portion is raised, receives the carrier brackets at a level above the delivery position of the uppermost tray, such that the carrier brackets become closely juxtaposed, with the ajoining chain por¬ tions hanging loopwise between the respective carrier brackets.