Title: Serving tray

The invention relates to a serving tray, comprising a substantially flat bearing surface for bearing products thereon.

Such a serving tray is generally known and is often provided with a barrier extending along the perimeter of the bearing surface. What is disadvantageous about the known serving tray is that the physical load during serving with the serving tray is high.

Research has shown that, in particular, carrying out short cyclic tasks is one of the greatest risk factors with respect to absence through illness in the hotel and catering industry. During serving up with the current serving trays, the wrist joint located under the serving tray is, as it were, fixed and the elbow cannot be stretched without the serving tray losing its horizontal orientation. As a result, the user needs to compensate in the back, the hips or the knees to bring the serving tray to table height.

From the prior art, a number of special hand-held serving trays are known with which gripping with the hand is facilitated.

DE 1 682 747 and G 6 9013038 describe a hand-held serving tray with a substantially flat bearing surface which is provided, at its perimeter, with an inwardly reaching recess which is provided with a thickening for gripping the serving tray with the hand. GB 2 282 746 describes a plate which is provided, at its perimeter, with an inwardly reaching recess which is provided with a thickening for gripping the plate with the hand.

US 3 948 474 and FR 2 532 883 describe a serving tray provided with receiving openings, which is provided with a flat-edged gripping opening for gripping the serving tray with the hand.

The invention contemplates a conventional serving tray of the type stated in the introduction, with which the physical load during serving can be reduced.

To this end, the invention provides a serving tray, comprising a substantially flat bearing surface for bearing products thereon, which bearing surface is provided, at its perimeter, with an inwardly reaching recess, while, at the location of the recess, a supporting surface directed substantially upwards and outwards with respect to the bearing surface is provided for supporting the wrist or upper arm of a user of the serving tray during use.

Due to the combination of recess and supporting surface, the physical load during serving out can be reduced considerably. In particular, the recess provides the user with more freedom of movement in the wrist joint during serving out. Due to this movement possibility, the whole arm gets more freedom of movement, so that fewer or no compensations need to be carried out with the rest of the body to bring the serving tray to table height. The supporting edge at the recess directed obliquely upwards and outwards acts as a support for the wrist during serving out, so that the total supporting surface is enlarged and the stability of the serving tray is better guaranteed. Further, this supporting edge directed upwards and outwards prevents the wrist joint from turning too much. During serving, the wrist joint is thus prevented from being able to get into a less favorable end position for receiving the load.

Further, due to the combination of the recess and the supporting edge directed obliquely upwards and outwards, the upper arm can be received in the recess and be supported by the supporting edge, so that the serving tray can be supported on the forearm. Thus, the center of gravity of the serving tray can be brought considerably closer to the body than normally, so that the physical load can be reduced greatly.

Due to these two ergonomic advantages during serving out and supporting, the physical load can be reduced, and the risk of physical complaints and fatigue can be reduced. Further, the serving out will proceed more efficiently. Also, with the aid of recess and supporting surface, it is achieved that the stability during serving out and supporting the serving tray is enhanced, so that the user loses less energy to correcting and compensating movements, and the risk of spilling and/or damage to crockery can be reduced.

In an advantageous manner, the supporting surface can be part of a barrier extending along the perimeter of the bearing surface.

The invention also relates to a serving tray comprising a substantially flat bearing surface for bearing products, which bearing surface is provided, at its perimeter, with an inwardly reaching recess for accommodating the user's wrist during use when he places his hand under the bearing surface for support.

The invention will be explained in more detail with reference to an exemplary embodiment shown in a drawing, in which:

Fig.l shows a schematic perspective view of a detail of a serving tray according to the invention in which the recess and supporting edge are well visible;

Fig. 2a shows a schematic perspective view of a user during serving out with a conventional serving tray;

Fig. 2b shows a schematic perspective view of a user during serving out with the serving tray of Fig. 1; Fig. 3 shows a schematic side elevational view in detail of the serving tray of Fig. 1 during serving out;

Fig. 4 shows a schematic perspective view of a user during supporting of the serving tray of Fig. 1 on the forearm; and

Fig. 5 shows a schematic side elevational view in detail of the serving tray of Fig. 1 during supporting on the forearm.

Further advantageous embodiments are set forth in the subclaims. It is noted that the Figures are only schematic representations of preferred embodiments of the invention, which are given by way of non-limiting exemplary embodiment. In the Figures, same or corresponding parts are designated by the same reference numerals.

Fig. 1 shows a serving tray 1, comprising a substantially flat bearing surface 2 for bearing products thereon, for instance refreshments to be served out. The bearing surface preferably has a substantially closed design. Within the concept of "substantially closed", in this context, the supporting surface may optionally be provided with small openings, for instance for ^* draining off moisture, which do not interfere with the function of bearing refreshments to be served out on the surface.

The bearing surface 2 is provided, at its perimeter 3, with a recess 4 reaching inwards with respect to the center M of the serving tray 1. At the location of the recess 4, a supporting surface 5 directed substantially upwards and outwards with respect to the bearing surface 2 is provided for supporting the wrist or upper arm of a user of the serving tray during use. In the exemplary embodiment, it is shown that the supporting surface 5 is part of a barrier 6 extending along the perimeter 3 of the bearing surface 2. As shown here, the bearing surface merges into the supporting surface, including an angle.

The angle between the supporting surface 5 and the bearing surface 2 is preferably about 130°. As will be explained in more detail hereinbelow, it can thus be achieved that the wrist joint is protected against too far a turning movement.

When the use of a serving tray according to the invention is compared with a conventional serving tray, various differences can be observed. In the following, a number of advantages of the use of a serving tray according to

the invention compared to the use of a conventional serving tray are described.

Serving out During serving out, a serving tray is usually brought to table height.

In the use of a conventional serving tray (Fig. 2a), the elbow cannot be stretched without the serving tray losing its horizontal orientation. Because the conventional serving tray impedes movement of the wrist, compensation needs to take place within the body to provide that the serving tray comes to table height. This compensation can be realized by bending forward in the back and hips and/or by bending the knees. As is shown in Fig. 2b, by use of the recess 4 with the serving tray 1 according to the invention, the elbow can be stretched, due to the fact that the recess 4 gives freedom of movement to the wrist joint. The supporting surface 5 then ensures an adequate support of the serving tray 1 on the edge of the wrist, and protects the wrist from turning too far.

Supporting

During supporting of the serving tray 1 according to the invention, the upper arm can be received in the recess 4, so that the serving tray 1 can be supported on the forearm. This is shown in Fig. 4. The angle which the upper arm then makes with respect to the forearm is approximately 130°, in particular 128°. This can be seen in Fig. 5.

To this end, during supporting, the serving tray 1 according to the invention can not only be positioned firmly on the upper arm, but the distance from the center of gravity of the serving tray to the body can also be kept relatively small. Thus, the moment that the biceps exerts to keep the serving tray 1 horizontal can be considerably less than when a conventional serving tray needs to be kept horizontal. In the use of a full serving tray of 8 kg, the moment which the biceps needs to exert in the use

of a serving tray 1 according to the invention can, for instance, be 800 Nmm, while this would be about 1600 Nmm in the use of a conventional serving tray.

Stability

During use of a serving tray, the stability is very important. With an optimal stability, the person who supports the serving tray needs to correct and to compensate less. This is because the supporting becomes easier. As a result, the supporting is less tiring, so that the serving performance can be better, for instance due to a reduced risk of spilling or falling crockery.

The stability of the serving tray depends on various factors, such as for instance the stiffness of the serving tray and the positioning of the crockery on the serving tray. During serving out, the center of gravity of the serving tray will continuously change position due to the fact that crockery is removed from the serving tray. Even so, the serving tray continuously needs to be balanced. Due to the supporting surface 5 directed obliquely upwards and outwards at the recess 4, during serving out, the serving tray 1 according to the invention can not only be supported on the hand, but also partly on the wrist, so that the supporting surface 5 is enlarged and the stability is better guaranteed. This is shown in Fig. 3.

The supporting surface 5 directed obliquely upwards and outwards then prevents the wrist joint from being bent to a maximum. What can thus be prevented is that the radius needs to pivot about the ulna to keep the hand horizontal, and that force needs to be produced in a position in which the muscle length is not optimal. Also during supporting on the arm, the supporting surface 5 directed obliquely upwards and outwards will enhance the stability by cooperation with the biceps of the upper arm.

Alternatively, the serving tray according to the invention can be designed as a serving tray comprising a substantially flat bearing surface for bearing products thereon without utilizing the supporting edge, which

bearing surface is provided, at its perimeter, with an inwardly reaching recess for accommodating the user's wrist during use when he places his hand under the bearing surface for support.

In the following, a number of preferred embodiments of the serving tray according to the invention will be discussed which are referred to by the name "Ergo-Tray".

Fig. 6 shows a schematic three-dimensional view of the Ergo-Tray, corresponding with Fig. 1.

Fig. 7 shows a schematic two-dimensional view of the top plan view of the Ergo-Tray with important points and measures of a rectangular tray with a circular recess.

Fig. 8 shows a schematic two-dimensional view of the top plan view of the Ergo-Tray with important points and measures of a round tray with a circular recess. For the Ergo-Tray, the shape of the serving tray 1 and of the recess 4 is not of immediate importance so that a great freedom of shape is created, although the sizes of the shapes are related to one another. With regard to the recess 4, some preconditions are made. The recess to create room for the wrist joint can be realized by making a recess in the tray 1, locally removing material or adjusting the shape of the tray 1 such that room to move is created for the wrist. Due to this recess 4, the limitations with regard to the movements of dorsal and palmar flexion are reduced compared with the conventional serving trays. What is preferred for the width of the recess 4 is the situation where the width of the recess 4 is larger than the wrist width, in order to thus realize the greatest freedom of movement of the wrist. This width (b) has a minimum dimension of approximately 40 mm and a maximum dimension of L (Fig. 7). In a preferred situation, this width is between approximately 60-110 mm. In addition, it holds for the Ergo-Tray that the size of the recess 4 in the inward direction depends on the location of the center of gravity Z of the serving tray 1 without load. The center of

gravity Z should at all times fall within the supporting area of the hand palm. The distance (SZ) between the center of gravity (Z) of the unloaded serving tray and the point of the serving tray which corresponds with the bend line of the wrist joint (S) is determined by the length of the hand (Fig. 7). In order to make the Ergo-Tray suitable for the great majority of all adults, the distance from the point of the serving tray 1 which corresponds with the bend line of the wrist joint (S) to the center of gravity of the unloaded serving tray (Z) should be maximally approximately 156 mm. Preferred is the situation in which the center of gravity Z of the serving tray 1 projects in the middle of the hand. In this preferred situation, distance SZ is approximately 50 mm to approximately 100 mm according to the average anthropometric values of adults in 2004. Further, it holds that the center of gravity Z of the serving tray 1 should not fall within the space of the recess 4. For a rectangular Ergo-Tray serving tray 1 (Fig. 7) of a length L and of a width B with a circular recess 4 of radius r, the distance from the end of the recess (point S) to the center of gravity Z can be calculated with the formula: 7 ₃ r ³

For a round Ergo-Tray serving tray (Fig. 8) of radius k with a circular recess 4 of radius r, the distance from the end of the recess (point S) to the center of gravity Z can be calculated with the formula:

πk ³ - πrk ² - ¹ / ₂ πr ³ + ² / ₃ r ^{3 b} ^ - Txk ² - Y ₂ TTi ²

It will be clear that the invention is not limited to the embodiments shown here. Many variants will be clear to a skilled person, and are

understood to be within the scope of the invention as set forth in the following claims.