Patent Publication Number: US-8978921-B2

Title: Crate

Description:
The present invention relates to a crate for accommodating products such as fruits and vegetables, and in particular, to a banana crate. 
     Crates for storing and transporting products such as fruits and vegetables are widely used in the market. Normally, such crates are light and stable, which makes them suitable for bringing the crops from the field to the customer. Especially for tropical fruits like bananas, it is common to harvest the crop while it is still unripe and pack it into the crates for subsequent shipping and transportation. On their journey, the fruits have time to ripe. Before the transport, the crates are usually stacked on top of each other and arranged side by side onto pallets. Here, often a specific crosstacking technique is used such as in case of a “five-down configuration”. In this five-down configuration, five crates are arranged adjacent to each other into a rectangular array, such that two of them form a row in the length direction and the other three form a row in the width direction. 
     However, one problem is that in such a configuration, a free and uniform air circulation between a short side (end wall) and a long side (side wall) of adjacent crates according to the prior art is not guaranteed. This is disadvantageous in that the fruits may not receive uniform temperature control during their transport and storage as a result of uneven distribution of air. 
     Another disadvantage of known crates is that the inner surfaces of their side walls are straight, very uneven and may comprise sharp and/or hard objects such as corners or edges. Therefore, especially products having rounded surface portions such as bananas, apples or oranges may easily be damaged by such raw surfaces. 
     Moreover, for the purpose of quality control, it may be required that a controller can have quick and easy access to the inside of a specific crate, when this crate (not the uppermost) is arranged in a stack of a plurality of crates. However, known crates do not offer this possibility, meaning that the controller has to partially disassemble and reassemble the stack, when taking a look into the interior of a specific crate is required. This procedure is inefficient and also not convenient, thereby representing a further disadvantage. 
     Finally, a further disadvantage associated with known open-top crates is that in case of stacking two of them on top of each other, products slightly sticking out beyond the upper end of the lower crate (e.g. curved portions of a banana) may be contacted by a load of the upper crate, eventually leading to a damage of the product. 
     It is therefore an object of the present invention to provide a crate allowing for an improved airflow, packaging, access for inspection, and stacking of transportable products. 
     SUMMARY OF THE INVENTION 
     According to an embodiment of the present invention, the crate comprises a bottom and two respective pairwise opposing side walls and end walls, each side wall comprising a plurality of vent holes in a region A extending along a horizontal direction of the side wall, and each end wall comprising a grip hole. Here, the region A is the distance d A  away from a corner of the crate, the distance d A  being equal to the distance d GH  the grip hole is away from the same corner of the crate. Furthermore, a height h A  of the region A is substantially equal to the height h GH  of the grip hole, i.e. the heights are such that same overlap at least partially in the height direction. 
     This insures a venting path for providing an optimum air flow between adjacent crates, which are, for example, arranged in the five-down configuration. Consequently, by this venting path, a fast and especially uniform airflow can be achieved, resulting in consistent temperature control for fruit quality. 
     According to embodiments, the plurality of vent holes may comprise a pair of vent holes having a combined shape similar to the grip hole. The plurality of vent holes may be spaced with a distance being less than a dimension of the grip hole. A vent hole of the plurality of vent holes may comprise a horizontal dimension being less than the dimension of the grip hole. The side walls and the end walls may be configured to be foldable with respect to the bottom, such that, in a folded state, a remaining volume of the crate is minimal. The bottom may comprise two pairs of ventilation openings, wherein each ventilation opening of the first pair has a width equal or larger than 40 mm and a length equal or larger than 126 mm, and wherein each ventilation opening of the second pair has a width equal or larger than 40 mm and a length equal or larger than 25 mm. Each vent hole of the plurality of vent holes may have a width equal or larger than 20 mm and a length equal or larger than 24 mm. Each grip hole may have a width equal or larger than 30 mm and a length equal or larger than 100 mm. 
     Embodiments of the invention concerns an arrangement of two crates according to embodiments of the invention, wherein the crates are arranged such that an end wall of a first crate is adjacent to a side wall of a second crate, wherein the first crate is configured to be aligned along a first longitudinal axis parallel to a side wall of the first crate, and wherein the second crate is configured to be aligned along a second longitudinal axis parallel to a side wall of the second crate, the first longitudinal axis and the second longitudinal axis being perpendicular to each other, wherein a side wall of the first crate and an end wall of the second crate are aligned, such that at least a partial overlap of the grip hole of the first crate and at least one vent hole of the plurality of vent holes of the second crate is provided, such that a venting path between the first crate and the second crate is provided. The plurality of crates may be configured as a five-down configuration, such that a venting path between adjacent crates is provided. 
     According to a further embodiment, each side wall comprises a smooth inner surface being shaped in a convex form towards the outside of the crate, thereby providing an inner surface for accommodating products having rounded surface portions and avoiding damage of the products. The side walls and end walls may comprise stiffening members, which are provided on a respective outer surface of the side walls and end walls only. The side walls and the end walls may be made of plastic to provide the smooth inner surface ( 810 ). The convex-shaped smooth inner surface may have a lateral curvature dimension less than a maximum lateral dimension of the side wall, wherein the inner surface is substantially curved in a region of the side wall only, where non-continuous stiffening member extending along a vertical direction of the side wall are interrupted, and wherein the region is a central region 
     According to a another embodiment, at least one end wall comprises a thinned portion, wherein the thinned portion is adapted to allow the user to cut the end wall for providing an inspection opening. The thinned portion of the end wall may be a groove surrounding a predefined area of the end wall, wherein the groove comprises a thickness more than half of the thickness of the end wall. The end wall ( 130 ) may further comprises a plurality of holes being arranged along the groove, each hole having a diameter larger than a width of the groove. The thinned portion may be configured to provide an openable portion hingedly attached to the end wall, when the thinned portion is cut by the user, wherein the predefined area is substantially rectangular, and wherein the groove is adjacent to at least three sides of the predefined area. The predefined area may be more than one third of an area of the end wall. The end wall ( 130 ) may be made of plastic. An arrangement of a plurality of crates according the according to embodiments of the invention may have the plurality of crates arranged adjacent to each other, such that at least one end wall comprising the thinned portion is accessible by the user. 
     According to a yet another embodiment, the bottom is arch-shaped curving towards the interior of the crate, such that a space S between a lower surface of the bottom and a plane P defined by a lower end of the crate is provided. This, essentially, allows to stack two crates on top of each other without squeezing or damaging products protruding from the lower crate into the space S. The bottom may be arch-shaped along a direction of an end wall or along a direction of a side wall of the crate. The bottom may be wavy-shaped along a direction of the side wall in a border region of the side wall, a first portion of the wavy-shaped bottom may be at a height of the plane, and a second portion of the wavy-shaped portion may be maximally at a height of a lower end of the upper portion. The bottom may comprises an upper portion and a lower portion recessed with respect to the outer point of the walls, and a distance of the recess may be equal to a thickness of the walls, allowing for engagement of the lower portion with a top opening of a further crate. The lower portion may have an area defined by an outer perimeter of the lower portion, and the upper portion may have an area defined by an outer perimeter of the upper portion, the side walls and end walls may comprise inner surfaces and outer surfaces, wherein an inner area may be defined by the inner surfaces at a upper end of the crate, and wherein an outer area may be defined by the outer surfaces at the upper end of the crate, wherein the area may be approximately equal the area and the area may be approximately equals the area. Embodiments define a stack of two crates according to the invention wherein a first crate and a second crate are configured to provide an inner area defined by the inner surfaces at an upper end of the first crate and an area defined by an outer perimeter of the lower portion of the second crate, wherein the area and the area are equal, such that the movement between the first crate and the second crate is prevented, when the second crate is stacked on top of the first crate. The bottom of the second crate may comprise a plurality of vent openings being configured to provide a venting path between the first crate and the second crate. 
     Other elements, features, steps, characteristics and advantages of the present invention will become more apparent from the following detailed description of the preferred embodiments with reference to the attached drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In the following, embodiments of the present invention will be explained with reference to the accompanying drawings, in which: 
         FIG. 1  shows a perspective view of an embodiment of a crate; 
         FIG. 2  shows a top view of the embodiment of the crate in accordance with  FIG. 1 ; 
         FIG. 3  shows a side view of a side wall of the embodiment of the crate in accordance with  FIG. 1 ; 
         FIG. 4  shows a side view of an end wall of the embodiment of the crate in accordance with  FIG. 1 ; 
         FIG. 5  shows a side view of the end wall and the side wall of the crate in accordance with  FIG. 1  mentally unfold at a corner of the same; 
         FIG. 6  illustrates dimensions of a plurality of vent holes and a grip hole according to a further embodiment of a crate; 
         FIGS. 7   a ;  7   b  show a perspective view of an arrangement of a plurality of crates of the embodiment of  FIGS. 1 to 5  in the partial five-down configuration; 
         FIG. 7   c  shows a side view of an end wall of a crate of arrangement in accordance with  FIGS. 7   a ;  7   b;    
         FIG. 7   d  shows a side view of a side wall of a crate of the arrangement in accordance with  FIGS. 7   a ;  7   b;    
         FIG. 7   e  shows a top view of a crate of the arrangement in accordance with  FIGS. 7   a ;  7   b;    
         FIGS. 8   a ;  8   b  show a perspective view of an embodiment of a plurality of crates of the embodiment of  FIG. 6  in the partial five-down configuration; 
         FIG. 8   c  shows a side view of an end wall of a crate of the arrangement in accordance with  FIGS. 8   a ;  8   b;    
         FIG. 8   d  shows a side view of a side wall of a crate of the arrangement in accordance with  FIGS. 8   a ;  8   b;    
         FIG. 8   e  shows a top view of a crate of the arrangement in accordance with  FIGS. 8   a ;  8   b;    
         FIG. 9  shows a detailed top view of a side wall of a further embodiment of a crate with a convex-shaped smooth inner surface; 
         FIG. 10  shows a perspective view of a further embodiment of a crate with an openable portion; 
         FIG. 11   a  shows a perspective view of a further embodiment of a crate with an arch-shaped bottom; 
         FIG. 11   b  shows a perspective view of a further embodiment of the crate in accordance with  FIG. 11   a;    
         FIGS. 12   a ,  12   b  illustrates details of the bottom of the embodiment of the crate in accordance with  FIGS. 11   a ;  11   b;    
         FIG. 13   a  shows a partial side view of an embodiment of a stack of two crates stacked on top of each other; and 
         FIG. 13   b  shows a partial side view of a further embodiment of the stack in accordance with  FIG. 13   a  with a space (S) between the two crates. 
     
    
    
     DESCRIPTION OF EMBODIMENTS OF THE INVENTION 
       FIG. 1  shows a perspective view of an embodiment of a crate  100 . The crate  100  comprises a bottom  110  and two respective pairwise opposing side walls  120  and end walls  130 . Referring to  FIG. 1 , the side wall  120  has a larger extent than the end wall  130 . Both the side walls  120  and the end walls  130  are foldable with respect to the bottom  110 . In particular, the side walls  120  and the end walls  130  are attached to the bottom  110  such that they can be folded onto it in the directions of the arrows, as shown in  FIG. 1 . In a folded state, the remaining volume of the crate  100  is minimal. This has the advantage that in the folded state, the crate  100  occupies only a low height. Therefore, a large number of empty crates may be stacked onto a pallet for transport. 
     In embodiments, the crate  100  is made of plastic in order to provide a low weight and a high stability for storage and/or transport applications. 
     As shown in  FIG. 1 , each side wall  120  comprises a plurality  125  of vent holes, while each end wall  130  comprises a grip hole  135 . The plurality  125  of vent holes is essentially located in a region A extending along a horizontal direction  101  of the side wall  120 . Here, the horizontal direction is defined as a direction along a longer side of a respective side wall. Moreover, the region A is essentially defined as a region surrounded by two continuous stiffening members  121 ,  122  in the vicinity of the upper end of the crate  100 , where a plurality  123  of non-continuous stiffening members is not interrupted. It can also be seen in  FIG. 1  that the side walls  120  and the end walls  130  may be fastened to each other by using a fastener  140 , when the crate  100  is in its unfolded state. 
       FIG. 2  shows a top view of the embodiment of the crate  100  in accordance with  FIG. 1 . In particular, the bottom  110  may comprise two pairs  210 ,  220  of ventilation openings, which may be symmetrically arranged with respect to an axis  205  parallel to the end wall  130  along a central longitudinal axis  201 . Specifically, each ventilation opening of the first pair  210  may have a width  212  equal or larger than 40 mm and a length  214  equal or larger than 126 mm, while each ventilation opening of the second pair  220  may have a width  222  equal or larger than 40 mm and a length  224  equal or larger than 25 mm. Here, the width is defined as a dimension parallel to the end wall  130 , while the length is defined as the dimension parallel to the side wall  120 . The two pairs  210 ,  220  of ventilation openings should be dimensioned such that they are large enough to provide a proper venting through the bottom  110 . However, they may not be chosen so large that specific products will fall out of the crate  100 . As can already be seen in  FIG. 2 , an inner surface  121  of the side wall  120  is configured to be bent towards the outside of the crate  100 , which will be described in detail later on. 
       FIG. 3  shows a side view of a side wall  120  of the embodiment of the crate  100  in accordance with  FIG. 1 . In the  FIG. 3  view, the plurality  125  of vent holes can be clearly seen. In particular, the plurality  125  of vent holes may comprise a pair  310  of vent holes. Together, these vent holes may have a combined shape similar to that of the grip hole  135  (comp.  FIG. 1 ). This is advantageous because by adapting the combined shape, it is possible to achieve an optimum overlap of the pair  310  of vent holes and the grip hole  135 , when, for example, two crates are arranged in a five-down configuration. With regard to  FIG. 3 , each vent hole of the plurality  125  of vent holes may have a width  312  equal or larger than 20 mm and a length  314  equal or larger than 24 mm. Here, the width is defined as a dimension in a vertical direction  301  of the side wall  120 , while the length is defined as a dimension in the horizontal direction  101  of the side wall  120 . Moreover, the continuous stiffening members  121 ,  122  and the plurality  123  of non-continuous stiffening members extending in the vertical direction  101  of the side wall  120  are clearly seen in  FIG. 3 . 
       FIG. 4  shows a side view of an end wall  130  of the embodiment of the crate  100  in accordance with  FIG. 1 . As can be seen in  FIG. 4 , the grip hole  135  is centered with respect to two edges  131 ,  132 , of the crate  100 . The grip hole  135  is also recessed with respect to an upper end of the crate  100  by a distance  133  of about 30 mm. In particular, by joining the grip hole  135  to a thickened upper frame portion  134  of the end wall  130 , a strong grip may be provided for carrying a loaded crate  100 . Referring to  FIG. 4 , the grip hole  135  may have a width  137  equal or larger than 30 mm and a length  139  equal or larger than 100 mm. Here, the width is defined as the dimension in a vertical direction  402  of the end wall  130 , while the length is defined as the dimension in a horizontal direction  401  of the end wall  130 . It can also be seen that the grip hole  135  tapers from a maximum horizontal extension at an upper point  136  to a minimum horizontal extension at a lower point  138 , thereby providing an ergonomic grip. The fastener  140  is also clearly visible in  FIG. 4 . The fastener  140  may be attached to the end wall  130  in that it can engage with the recess  128  provided in a portion  126  of the side wall  120 . Here, the fastening mechanism may work on the basis that a displacement element  142  of the fastener  140  can be displaced against the force of a spring element. Additionally, as already indicated in  FIG. 4 , the end wall  130  may comprise a thinned portion  410  essentially surrounding a central portion of the end wall  130  including a part of the grip hole  135 . The purpose and more details regarding the thinned portion  410  will be described later. A further characteristic feature of the end wall  130  is that a plurality  420  of stiffening members may be provided close to a border region of the end wall  130 . This provides an increased ability supporting the above-mentioned fastening mechanism. 
     Arrangement of the Vent Holes (1 st  Aspect) 
     A first aspect of the present invention addresses the disadvantage that in a five-down configuration, for example, a uniform air flow is not provided between adjacent crates according to the prior art. 
       FIG. 5  depicts the end wall  130  and the side wall  120  of the crate  100  mentally unfold at the same corner  505  of the crate  100 . Alternatively,  FIG. 5  may also illustrate an end wall  512  of a first crate  510  adjacent to a side wall  522  of a second crate  520 , wherein the first crate  510  is aligned with the second crate  520  at the corner  505 . As depicted, the side wall  120  of the crate  100 , or alternatively, the side wall  522  of the second crate  520  comprises the plurality  125  of vent holes in a region A. The region A is indicated in  FIG. 5  by a dashed line  501 . In embodiments, the region A is a distance d A  away from the corner  505  and has a height h A . Furthermore, the end wall  130 , or alternatively, the end wall  512  of the first crate  510  comprises the grip hole  135 . In embodiments, the grip hole  135  is a distance d GH  away from the same corner  505  and has a height h GH . It can be seen in the  FIG. 5  embodiment that the distance d A  is approximately equal to the distance d GH  and the height h A  is approximately equal to the height h GH . Therefore, especially in the five-down configuration (see  FIGS. 7   a ,  7   b ,  8   a ;  8   b ), at least a partial overlap of the grip hole  135  of the first crate  510  and at least one vent hole (e.g. vent hole  515 ) of the second crate  520  may be provided, and consequently, venting paths between the two crates  510 ,  520  will be obtained. 
       FIG. 6  illustrates dimensions of a plurality  615  of vent holes and a grip hole  135  according to a further embodiment of the crate  100 . The plurality  615  of vent holes shown in  FIG. 6  may correspond to the plurality  125  of vent holes shown in  FIG. 3 . In the  FIG. 6  embodiment, the plurality  615  of vent holes is spaced along the horizontal direction  101  of the side wall  120  with a distance s VH . In addition, each vent hole may have the same extent and may be rectangular-shaped. The distance s VH  may be chosen such that it is less than a dimension l GH  of the grip hole  135 , wherein the dimension l GH  may correspond to the maximum horizontal extent  139 , as shown in  FIG. 4 . In addition, the horizontal dimension l VH  of a vent hole may be chosen less than the dimension l GH  of the grip hole  135 . A vertical dimension of the vent hole along the vertical direction  301  may also be less than the vertical extent of the grip hole  135 . Therefore, a characteristic dimension of the plurality  615  of vent holes is generally configured to be smaller than that of the grip hole  135 , such that an overlap of the at least one vent hole  515  with the grip hole  135  may be provided, such as in case of the five-down configuration. 
       FIGS. 7   a ;  7   b  show a perspective view of an arrangement  700  of a plurality of crates of the embodiment described with respect to  FIGS. 1 to 5  in a partial five-down configuration. In this context, ‘partial’ means that only three instead of five crates  100  of the five-down configuration are shown. Referring to  FIGS. 7   a  and  7   b , the two specific crates  510 ,  520  are arranged such that the end wall  512  of the first crate  510  is adjacent to the side wall  522  of the second crate  520 . Here, the first crate  510  is aligned along a first longitudinal axis  701 , while the second crate  520  is aligned along a second longitudinal axis  702 . As can be seen in  FIGS. 7   a ;  7   b , the first longitudinal axis  701  and the second longitudinal axis  702  are perpendicular to each other. Moreover, a side wall  720  of the first crate  510 , which may correspond to the side wall  120  of  FIG. 3 , and an end wall  730  of the second crate  520 , which may correspond to the end wall  130  of  FIG. 4 , are aligned to be flush in this partial five-down configuration. Correspondingly, the at least partial overlap of the grip hole  125  of the first crate  510  and the at least one vent hole of the plurality  125  of vent holes of the second crate  520  may be provided. The thus obtained venting path  710 , which is indicated by a dark arrow, shows a venting path for the air flow, thereby securing a proper ventilation of the respective interior of the crates  510 ,  520 . 
       FIGS. 7   c ,  7   d  and  7   e  show different views of the end wall  512 , the side wall  522  and the crate  510 , respectively. Specifically, in the shown embodiments, further different formations of ventilation regions  705 ;  706 ;  709  in the lower part of the crate  510  may be provided, eventually leading to better ventilation properties. 
       FIGS. 8   a ;  8   b  show a perspective view of an arrangement  700  of a plurality of crates of the embodiment described with respect to  FIG. 6  in a partial five-down configuration. In this context, ‘partial’ means that only three instead of five crates  100  of the five-down configuration are shown. Referring to  FIGS. 8   a  and  8   b , the two specific crates  510 ,  520  are arranged such that the end wall  512  of the first crate  510  is adjacent to the side wall  522  of the second crate  520 . Here, the first crate  510  is aligned along a first longitudinal axis  751 , while the second crate  520  is aligned along a second longitudinal axis  752 . As can be seen in  FIGS. 8   a ;  8   b , the first longitudinal axis  751  and the second longitudinal axis  752  are perpendicular to each other. Moreover, a side wall  770  of the first crate  510  and an end wall  780  of the second crate  520  are aligned to be flush in this partial five-down configuration. Correspondingly, the at least partial overlap of the grip hole  135  of the first crate  510  and the at least one vent hole  515  of the plurality  615  of vent holes of the second crate  520  may be provided, wherein the overlap region  765  is indicated by a dark mark. The thus obtained venting path  760 , which is indicated by an arrow, shows a venting path for the air flow, thereby securing a proper ventilation of the respective interior of the crates  510 ,  520 . 
       FIGS. 8   c ,  8   d  and  8   e  show different views of the end wall  512 , the side wall  522  and the crate  510 , respectively. Specifically, in the shown embodiments, further different formations of ventilation regions  755 ;  756 ;  759  in the lower part and/or close to a corner (region  757 ) of the crate  510  may be provided, eventually leading to better ventilation properties. 
     Inner Surface of the Crate (2 nd  Aspect) 
     A second aspect of the present invention addresses the further disadvantage that the inner surfaces of the side walls of known crates are straight and not free of sharp and/or hard objects. 
       FIG. 9  shows a top view of the side wall  120  of the crate  100  in more detail. It can be seen in  FIG. 9  that the side wall  120  comprises stiffening members  815  including the stiffening members  121 ,  122 , which were also shown in  FIG. 1 . The side wall  120  may comprise a smooth inner surface  810  being shaped in a convex form towards the outside of the crate  100 . In addition, the stiffening members  815  may be provided on the outer surface of the side wall  120  only. In order to provide the smooth inner surface  810 , the crate  100  or at least the side wall  120  can be made of plastic. It can be seen in  FIG. 9  that the convex-shaped smooth inner surface  810  has a lateral curvature dimension l c  less than a maximum lateral dimension d SW  of the side wall  120 . Here, the lateral dimension is defined as the dimension in a lateral direction  801  perpendicular to the side wall  120 . The inner surface  810  is substantially curved in a region B of the side wall  120  only. With regard to  FIG. 3 , this region B is defined as a region, where the non-continuous stiffening members  123  extending along the vertical direction  301  are interrupted. The region B is therefore a central region, which is not close to a corner  805  of the crate  100 , and which is essentially bordered by the continuous stiffening members  121 ,  122 . The advantage of using the convex-shaped inner surface  810  is that on the one hand, the crate  100  will especially be suitable for accommodating products with rounded surface portions. On the other hand, since the inner surface  810  can be made very smooth, i.e. without sharp edges or corners, the risk of damaging or crushing the transportable products during their transport may be minimized. 
     Quick Access to the Crate Interior (3 rd  Aspect) 
     A third aspect of the present invention addresses the further disadvantage regarding the lack of possibility of quick and easy access to the inside of a specific crate, when the same is, for example, stacked into a column onto a pallet. 
       FIG. 10  shows a perspective view of a further embodiment of a crate  100  with an openable portion. In the  FIG. 10  embodiment, the end wall  130  comprises a thinned portion  910 , which may correspond to the thinned portion  410  shown in  FIG. 4 , wherein the thinned portion  910  may be configured as a groove. This groove  910  is made in the end wall  130  and surrounds at least three sides of a predefined area  905 . As can be seen in the  FIG. 10  embodiment, the predefined area  905  is substantially rectangular. The zoom view shows that the groove  910  comprises a thickness l GR  in a direction perpendicular to the end wall  130 , which is more than half of the thickness l EW  of the end wall  130 . This characteristic of the groove  910  allows for an easy cutting thereof. Furthermore, along the groove  910 , a plurality  915  of holes may be arranged, wherein each hole may have a diameter  917  larger than a width  912  of the groove  910 . The width  912  may typically be equal or larger than 6 mm (see also  FIG. 4 ). The dimensioning of the holes  915  is therefore such that a knife, which is commonly used by a controller, can be easily introduced into them and then cut along the groove  910 . By cutting the groove  910 , an openable portion  920  may be provided, which is essentially attached to the end wall  130 . The openable portion  920  can be unfolded as indicated by the arrow. The purpose of providing such an openable portion is that the user can take a look inside the interior of the crate  100  for inspecting the accommodated products. For example, it can be checked whether carried fruits such as bananas have already reached a certain degree of ripeness. Again, the end wall  130  may be made of plastic, such that a normal knife can be used by the controller. The  FIG. 10  embodiment shows also that the predefined area  905  may be more than one third of an area of the end wall  130  so as to provide a large enough inspection opening. In embodiments, where two or more crates  100  are stacked adjacent to each other, such as in the five-down configuration partially shown in FIGS.  7   a ;  7   b ,  8   a ,  8   b , they should be arranged such that the groove  910  of at least one end wall  130  may be accessible by a user. 
     Arch-Shaped Crate Bottom (4 th  Aspect) 
     A fourth aspect of the present invention addresses the further disadvantage that products protruding from a lower crate may be damaged by a load of an upper crate, when the upper crate is stacked on top of the lower crate. 
       FIGS. 11   a ,  11   b  show perspective views of further embodiments of a crate  100 , wherein the bottom  110  is particularly arch-shaped curving towards the interior of the crate  100 . The bottom  110  may either be curved along a direction  1001  of the end wall  130  (see  FIG. 11   a ) or along a direction  1002  of the side wall  120  (see  FIG. 11   b ). As can be clearly seen in the  FIGS. 11   a ,  11   b , both designs provide an additional space S between a lower surface of a bottom  110  and a plane P. Here, the plane P is defined by a lower end of the crate  100 , respectively. 
       FIGS. 12   a ,  12   b  show more details of the bottom  110  of further embodiments of the crate  100  in accordance with  FIGS. 11   a ,  11   b . In particular,  FIG. 12   a  is a partial section view along a line L 1 -L 1  of  FIG. 11   a , while  FIG. 12   b  is a partial section view along a line L 2 -L 2  of  FIG. 11   a . In both  FIG. 12   a  and  FIG. 12   b , the bottom  110  comprises an upper portion  1110  and a lower portion  1120 , wherein the lower portion  1120  may be recessed with respect to an outer point  1101  of the walls of the crate  100 . As can be clearly seen in the section view of  FIG. 12   a , the lower portion  1120  of the bottom  110  may be curved upwards along the direction  1001 , such that a bulge  1125  will be obtained. The additional space S that is created is depicted in  FIG. 12   a  as a gradual increase of a cross-sectional area to the right. 
     The partial section view of  FIG. 12   b  shows that the bottom  110  may have a wave like shape along the direction  1002  in the vicinity of the side wall  120 . Note that L 2 -L 2  is taken at a border region of the crate  100 , as shown in  FIG. 11   a . In particular, the wave like shape of the bottom  110  causes bulges  1125  to be located along the direction  1002 , i.e. along the end wall  120 , which makes the bottom  110  very rigid. 
     In further embodiments, starting from a central longitudinal axis of a crate  100 , the curvature of the bulges  1125  may also become gradually more pronounced in the direction  1001  (i.e. in a direction closer to the side wall  120 ). 
     In further embodiments, a first portion of the wavy-shaped bottom  110  is at a height of the plane P, while a second portion of the wavy-shaped bottom  110  is maximally at a height of a lower end of the upper portion  1110  corresponding to a maximum extent of the wave like shape. 
       FIGS. 13   a ,  13   b  show side views of further embodiments, wherein, for example, two crates  1210 ,  1220  are stacked on top of each other. Both in the  FIG. 12  and  FIG. 13  embodiments, a distance d R  of the recess may be chosen such that it will be equal to a thickness l W  of the walls. In this way, an engagement of the lower portion  1120  of the second crate  1220  and a top opening of the first crate  1210  may be achieved, therefore preventing a lateral movement in a direction  1201  shown in  FIG. 13   a.    
     In further embodiments, the lower portion  1120  has an area A LP  defined by an outer perimeter of the lower portion  1120 , while the upper portion  1110  has an area A UP  defined by an outer perimeter of the upper portion  1110 . Moreover, an inner area A IS  may be defined by the inner surfaces of the walls at an upper end of the crate  100 , while an outer area A OS  may be defined by the outer surfaces of the walls at the upper end of the crate  100 . In particular, the area A LP  approximately equals the area A IS , while the area A UP  approximately equals the area A OS . 
     In further embodiments, an inner area A IS, 1  defined by the inner surfaces at an upper end of the first crate  1210  and an area A LP, 2  defined by an outer perimeter of the lower portion  1120  of the second crate  1220  may be equal, such that the first crate  1210  and the second crate  1220  fit accurately together, when the second crate  1220  is stacked on top of the first crate  1210 . 
     In further embodiments, the bottom  110  of the second crate  1220  may also comprise a plurality of vent openings so as to provide a venting path between the first crate  1210  and the second crate  1220 . 
     Referring to  FIG. 13   b , the advantage of providing the additional space S is that in practice, when two or more crates are stacked on top of each other into a column onto a pallet, products  1205  extending beyond an upper end of the lower crate  1210  of the column, such as the curved portions of a banana protruding the plane P, may be efficiently protected from being squeezed by heavy load of the upper crate  1220  of the column. 
     In summary, embodiments of the present invention provide a crate such as a banana crate, wherein the design of the vent holes of the crate allows for proper venting of the interior of the crate even in case same is stacked such that two crates are arranged such the end wall of one crate is adjacent to a side wall of another crate (e.g. a five-down configuration). Specifically, by providing a venting path, a uniform air distribution and therefore a consistent temperature control for fruit quality may be achieved with such a design. 
     Here, the arrangement of the vent holes in the side walls is to be such that at least one vent hole is to be provided in the side wall at a distance from each corner, the distance being equal to the distance the grip hole in the end wall is away from the same corner, thereby ensuring at least a partial overlap of the grip hole and at least one vent hole in case of stacking the plurality of crates as mentioned above. In accordance with further embodiments pairs of vent holes may be provided that together may have a shape similar to the grip hole. Also, a plurality of vent holes being equally spaced may be provided with a spacing being less than the dimension of the grip hole. 
     A further aspect of embodiments is the smooth inside surface thereof being shaped in convex form towards the outside and therefore products with rounded surfaces, like bananas, are more easily accommodated at the side portions of the crate by providing the convex or curved inner surface. This may apply for both the side walls and for the end walls. In accordance with further embodiments, stiffening members like ribs and the likes are provided only on the outside of the crate. 
     Yet another feature of embodiments is the provision of a thinned portion in the end walls allowing a cutting thereof to provide for an opening, allowing a user of the crate to take a look into the interior of the crate, which is important for determining for a complete batch of crates whether the product inside the crate, for example bananas, already reached a desired degree of ripeness. 
     The fourth feature concerns the bottom which is arch-shaped. This does not have any direct impact on the products inside the crate, but upon stacking a plurality of crates on top of each other. This allows for provided additional space in a crate below, thereby avoiding damaging product which slightly stick out beyond the upper end of the lower crate. The arch- and wavy-shaped bottom allows accommodating such products slightly sticking out in the crate below. 
     The above described embodiments are merely illustrative for the principles of the present invention. It is understood that modifications and variations of the arrangements and the details described herein will be apparent to others skilled in the art. It is the intent, therefore, to be limited only by the scope of the impending patent claims and not by the specific details presented by way of description and explanation of the embodiments herein.