Abstract:
A system for distributing articles into an internal compartment of a storage unit has a longitudinally displaceable support or platform above the compartment which is movable longitudinally between a plurality of spaced discharge areas over corresponding storage positions. The support has at least one free edge, and is moved until an article carried on the support is displaced by a pusher moved into the path of the article and pushed over the edge to drop into the selected storage position. In one example, the support has opposite free edges and articles are selectively pushed over the edges into different storage positions. The process is repeated to dispense articles into different storage positions for uniform filling, and to control movement of the support and deployment of the pusher so that articles are dispensed into the storage positions with available space.

Description:
FIELD OF THE INVENTION 
     The present invention concerns a method for distributing articles made by series production in a storage compartment. 
     The invention furthermore concerns an apparatus for performing the method. 
     BACKGROUND OF THE INVENTION 
     The invention has appeared during development of machines for making and delivering bags with loose ice cubes in supermarkets. Such machines are designed with a top part with an ice cube machine and a central packing machine packing the ice cubes loosely in bags, and a lower part with a storage compartment from where the filled ice cube bags are supplied as the customer opens an access door to the storage compartment, providing himself with a desired number of ice cube bags. An example of such a machine is described in the applicant&#39;s patent application WO 2008/089762. 
     In connection with such machines it is a problem that the bags fall down into the storage compartment over the same position. Over time, the stack of bags will form a pyramid. This causes the storage compartment to be badly utilised as it will only be partially filled, resulting in low capacity for a storage compartment of a given size. The storage compartment will rapidly reach a level and thereby a degree of filling where additional bags cannot be produced, before the filling degree is reduced. 
     The lower capacity of the storage compartment entails that the ice cube machine is to be dimensioned with a relatively high capacity in order to cope with peak loads. These occur e.g. in connection with festivals or by sudden rises in the outdoor temperature because of change in weather. 
     The problem has hitherto been solved by the staff in the supermarket performing a manual levelling of the ice cube bags in the storage compartment at short intervals. There is a desire to avoid this manual levelling as there are work safety considerations that limit the time in which the employees are allowed to work with frozen products, and a desire to release the employees&#39; resources for other purposes in the supermarket. 
     The machine will also find application in connection with distribution of other serially produced articles in a storage compartment where distribution of the articles in an even layer is wanted. 
     OBJECT OF THE INVENTION 
     It is the object of the invention to indicate a method and an apparatus that ensure an even distribution of articles, in particular bags with ice cubes made in a large number, in a storage compartment, particularly in an ice cube distribution machine in a supermarket. 
     DESCRIPTION OF THE INVENTION 
     According to the present invention, this is achieved by a method of the kind mentioned in the introduction which includes the following steps:
         A. placing the article on a longitudinally displaceable conveyor above the storage compartment;   B. displacing the article by the conveyor to a discharge area which is selected among at least two discharge areas in the storage compartment;   C. discharging the article by pushing it off over one or the other edge of the conveyor by moving the conveyor over the discharge area;   D. repeating steps A-C with selection of discharge area in a controlled sequence.       

     The apparatus according to the invention is peculiar in that it includes:
         a conveyor with a support surface for an article;   a drive means for longitudinal displacement of the support surface of the conveyor;   at least one pushing off means;   at least one drive means for inserting the at least one pushing off means in the path of the article;   a control means.       

     By a system according to the present invention, it is possible to achieve an even distribution of articles produced in series in a storage compartment in a simple way. 
     The system is developed for use in ice cube distribution machines for installation in e.g. supermarkets where the ice cubes are made in situ according to need, and are packed immediately before being put in a storage compartment under the ice cube machine. 
     The system for levelling can be applied to other types of machines than ice cube distribution machines, where a large number of articles are produced centrally above a storage compartment in which the articles are to be evenly distributed in order to utilise the capacity of the storage compartment. Examples of such applications could be in connection with a plastic injection moulding machine where a large number of articles are produced centrally, or in connection with packing and supplying other types of foods, e.g. vegetables or confectionery. 
     In the present application, the above mentioned ice cube distribution machine is used as example but this does not exclude other kinds of systems. 
     The conveyor is provided a support surface upon which the article is placed. This support surface has a horizontal orientation such that the article does not slide off the conveyor by itself, both during its start-up, movement and standstill. 
     The article is moved by the longitudinal displacement of the conveyor. This longitudinal displacement of the article is performed from an initial position where the article is delivered to the apparatus from the preceding production step to a desired discharge area above the storage compartment. For example, from an initial position under a dispenser unit for packed ice cube bags in an ice cube distribution machine to a discharge area above a position in the discharge space in the lower part of the machine from where the customers pick up the ice cube bags. 
     The number of discharge areas is determined with regard to the extension of the storage compartment along the displacement direction of the conveyor such that the distribution of articles in the storage compartment becomes even. 
     In practice, during the development of an ice cube distribution machine with a storage compartment having a length of about 2 m, it has appeared that there is achieved a suitable even distribution of ice cube bags in the storage compartment with four discharge areas. 
     The conveyor may be of a type where the support surface is formed on a slide which is suspended on an endless conveyor means. The endless conveyor means may e.g. be a chain with a path formed by a number of sprocket wheels. The slide is formed with free edges along open sides transversely to the direction of movement, and suspended along edges which are parallel with the direction of movement. Pushing off is effected over one or the other edge at one or the other side, respectively, which are transverse to the direction of movement. 
     A pushing off means is introduced in the path of the article. The pushing off means is oriented largely perpendicularly to the direction of movement of the conveyor and stationary during pushing off. Pushing off is effected by longitudinal displacement of the slide and thereby the support surface for the article. The article has no relative movement in relation to the pushing off means, but the article moves relatively to the slide over the edge, finally falling down over the discharge area in the storage compartment under the action of gravity and due to the relative movement between the support surface for the article and the pushing off means. 
     Pushing off occurs over the edge which is rearmost relative to the direction of movement of the slide. 
     Alternatively, the conveyor may be of a type where the support surface is formed by an endless conveyor belt. The conveyor belt has free edges along two sides which are parallel with the direction of movement of the conveyor. Pushing off is effected over one or the other edge at one or the other of the sides, respectively, which are parallel with the direction of movement of the conveyor. 
     A pushing off means is introduced over the conveyor belt in the path of the article. The pushing off means is oblique in relation to the direction of movement of the article and stationary during the pushing off. Pushing off is effected by longitudinal displacing the support surface of the conveyor belt for the article by interaction with the oblique stationary pushing off means, whereby the article is forced over one or the other edge of the conveyor, depending on the direction of the oblique orientation of the pushing off mechanism. 
     The discharge areas thus lie at each side of the conveyor. 
     Besides, the conveyor belt may have free edges at its ends. This provides a further discharge area for each free edge. 
     It applies to both types of conveyors that the conveyor means do not need to be endless. They are just to be arranged such that the direction of movement may be reversed when the support surface of the article reaches an extreme position. 
     The type of conveyor is chosen with regard to the shape of the storage compartment. 
     By storage compartments that are narrow in relation to the width, there is chosen a conveyor with free sides and edges transversely to the direction of movement in order to have discharge areas directly under the conveyor, and thereby to achieve discharge areas in one row. 
     By storage compartments that are wide in relation to the width, there is chosen a conveyor with free sides and edges in parallel with the direction of movement in order to have discharge areas at each side of the conveyor, and thereby to achieve discharge areas in two rows. 
     The pushing off means may be an arm which may freely be introduced in the path of the article and removed according to need. 
     Two discharge areas for each pushing off means may be attained, as the drive means for the conveyor may be selected among types with reversing direction of movement, such as electric, hydraulic or pneumatic motors or linear actuators. 
     An example of such a method according to the invention with one pushing off means and two discharge areas includes the steps:
         A. Placing the article on a longitudinally displaceable conveyor above the storage compartment;   B. Displacing the article by the conveyor to a first discharge area in the storage compartment;   C. Discharging the article by pushing it off over one edge of the conveyor by moving the conveyor over the discharge area in a direction away from an initial position, after which the direction of displacement of the conveyor is reversed and it returns to the initial position for repeating the steps, as follows:
           A′. Placing a new article on the longitudinally displaceable conveyor above the storage compartment;   B′. Displacing the article by the conveyor to a second discharge area in the storage compartment;   C′. Discharging the article by pushing it off over the other edge of the conveyor by moving the conveyor over the discharge area in a direction against the initial position, after which the conveyor continues back to the initial position for repeating steps A-C or A′-C′, depending on the selected sequence.   
               

     When the article is discharged over the first discharge area, the pushing off means may be introduced in the path of the article before performing step B, while it before discharging the article over the second discharge area is introduced after performing step B. 
     In a simple way is hereby achieved that each pushing off means may cover two discharge areas. 
     The drive means for introducing the pushing off means may be electrically, hydraulically or pneumatically driven and based on a linear or rotating movement, or a combination of the two. Several pushing off means may advantageously be connected with the same drive means such that they are introduced in the path of the article at the same time. This provides a more simple design. The coupled pushing off means are introduced in the path of the article immediately before discharge as one hereby avoids the article being discharged over a wrong discharge area. 
     The apparatus is provided with a control means connected with the drive means of the apparatus. The control means can be based on an electronic circuit which may possibly be programmable. Alternatively, the control means can be a pure mechanical control which e.g, may be established by a hydraulic or pneumatic circuit. 
     In a particularly advantageous embodiment of the method according to the invention, this is peculiar in that the sequence for selection of the discharge area of each article is controlled by the steps:
         detecting degree of filling in each discharge area in the storage compartment   comparing degrees of filling;   selecting a discharge area on the basis of the said comparison.       

     The apparatus according to the embodiment of the method is peculiar in that it includes at least one level measuring means which is adapted for detecting the degree of filling in each discharge area in the storage compartment. 
     In connection with systems where one or more users take articles from the storage compartment, the degree of filling in the discharge areas may be different due to the fact that the articles are taken from the discharge areas at different rates. By actively detecting the degree of filling in the individual discharge areas and adapting the sequence of selecting discharge area on the basis of a comparison of the degrees of filling in each discharge area, there is achieved a levelling that takes account of user interaction. 
     An example, where a distribution machine has four discharge areas—1, 2, 3, 4—the sequence for selecting discharge area may be as follows:
         Filling degree for all discharge areas &lt;100%
           Discharge over the discharge areas in a uniform sequence, one by one, e.g. 1, 2, 3, 4, 1, 2, 3, 4, 1, etc.   
           Filling degree of a discharge area (e.g. area  1 )=100%, remaining areas &lt;100%
           Discharge over the discharge areas in a sequence that excludes the filled area, e.g. 2, 3, 4, 2, 3, 4, 2, etc.   
           Filling degree of several discharge areas (e.g. area  1 ,  4 )=100%, remaining areas &lt;100%
           Discharge over the discharge areas in a sequence that excludes the filled areas, e.g. 2, 3, 2, 3, 2, etc.   
           Filling degree of several discharge areas (e.g. area  1 ,  2 ,  4 )=100%, remaining area &lt;100%
           Discharge over the discharge areas in a sequence that excludes the filled areas, e.g. 3, 3, 3, etc.   
           Filling degree of all discharge areas=100%
           The system for levelling is stopped and discharge is suspended until the degree of filling in the discharge areas reach a low value.   
               

     Monitoring the filling degree may furthermore be utilised for controlling the production of articles. 
     For example, the said ice cube distribution machine may be provided with two ice cube dispensers that deliver ice cubes to a common packing unit. When the filling degree in half of the discharge areas reach 100%, it may be decided to close one ice cube dispenser and thereby control the production such that optimal efficiency and minimal idling time is achieved for the units in the production machinery. 
     Hereby is achieved less energy consumption and longer service life for the whole distribution machine including production machinery. 
     In a particularly advantageous embodiment of the method according to the invention, this is peculiar in that the conveyor is elevated to a first height while performing step A, and that the conveyor is lowered to a second height before performing step B. 
     The apparatus according to the embodiment of the invention is peculiar in that it includes
         a drive means for vertical displacement of the support surface of the conveyor.       

     This embodiment of the method and the apparatus is particularly advantageous in connection with systems of a type known from the applicant&#39;s patent application WO 2008/089762 where the ice cubes are packed in film bags that are closed by welding while using welding jaws. 
     During filling of a film bag, this typically hangs freely in the machine such that it is possible to fill the film bag to a given weight which is measured by a weighing cell. Then the conveyor is lifted to a first height, whereby support of the film bag, which is the article, is gradually taken over by the conveyor until the former is fully supported on the support face of the conveyor. The film web is now fully relieved and not influenced by tensile forces induced by the weight of the filled film bag. Hereby is achieved a better welding as severing the film web by melting before establishing the necessary weld seams is avoided. A loaded film web will rapidly be deformed in direction of the tensile forces when melting under the action of the welding jaws such that the film bag is inadvertently released from the film web. 
     The conveyor has drive means for the vertical displacement. This drive means may include a linear actuator in the form of a hydraulic or pneumatic cylinder connected with the suspension points of the conveyor, a parallelogram or a guide for guiding the conveyor during the vertical displacement. 
     In an embodiment of the invention, wherein the conveyor includes a slide connected with an endless conveyor means in the form of a chain provided with a path formed by a number of sprocket wheels, the path is arranged such that by means of sprocket wheels at different levels and distances it provides the slide with a path where it may be displaced in height by passing the initial position for placing the articles, and be displaced in longitudinal direction towards the discharge positions. 
     In a particularly simple way there is hereby achieved the ability of combining longitudinal displaceability with vertical displaceability of the conveyor by means of the same construction element in the apparatus. The same drive means is used for longitudinal displacement and vertical displacement. 
    
    
     
       DESCRIPTION OF THE DRAWING 
       The invention will be explained in more detail below with reference to the accompanying drawing, where: 
         FIG. 1  shows an isometric view of an ice cube distribution machine; 
         FIG. 2  shows a side view of an ice cube distribution machine; 
         FIG. 3  shows a first isometric view of an apparatus for distributing articles; 
         FIG. 4  shows a second isometric view of an apparatus for distributing articles; 
         FIG. 5  shows a view of an apparatus for distributing articles, as seen from above and with the conveyor at an initial position with an article on the support surface; 
         FIG. 6  shows a view of the apparatus, as seen from above and with the conveyor at a position on its way to discharge the article in a first discharge area; 
         FIG. 7  shows a view of the apparatus, as seen from above and with the conveyor at a position during discharge of the article in a first discharge area; 
         FIG. 8  shows a view of the apparatus, as seen from above and with the conveyor at a position on its way to the initial position; 
         FIG. 9  shows a view of the apparatus, as seen from above and with the conveyor at an initial position with an article on the support surface on its way to a second discharge area; 
         FIG. 10  shows a view of the apparatus, as seen from above and with the conveyor at a position on its way to discharge the article in the second discharge area; 
         FIG. 11  shows a view of the apparatus, as seen from above and with the conveyor at a position on its way to the initial position and after discharging the article in the second discharge area; 
         FIG. 12  shows a side view of the apparatus with the conveyor at a first height; 
         FIG. 13  shows a side view of the apparatus with the conveyor at a second height; 
         FIG. 14  shows a second side view of the apparatus with the pushing off means at a position outside the path of the article; and 
         FIG. 15  shows a second side view of the apparatus with the pushing off means at a position within the path of the article. 
         FIG. 16  illustrates a top plan view of a second embodiment of a dispensing conveyor apparatus in which articles are dispensed from opposite sides of a conveyor. 
     
    
    
     In the explanation of the Figures, identical or corresponding elements will be provided with the same designations in different Figures. Therefore, no explanation of all details will be given in connection with each single FIGURE/embodiment. 
     DETAILED DESCRIPTION OF THE INVENTION 
       FIG. 1  shows an isometric view of an ice cube distribution machine  16 . The machine  16  is shown as example of an application of the method and the apparatus  1  (see  FIG. 2 ) which are objects of the present application. 
     The machine  16  includes a top part with two ice cube machines  17  and a centrally disposed packing machine  18  and a bottom part with a storage compartment  3 . 
     The ice cube machines  17  supply ice cubes down into film bags which are closed in the packing machine  18 . A filled and closed film bag is termed an article  2  (see  FIG. 2 ) in the present application. The apparatus  1  (see  FIG. 2 ) for distributing articles  2  (see  FIG. 2 ) is disposed under the packing machine  18 . 
       FIG. 2  shows a side view of the machine  16  where the front side of the packing machine  18  and the storage compartment  3  are open so that one may see into the machine  16 . 
     The apparatus  1  is suspended under the packing machine  18  which is a dispenser of the articles  2  (see  FIG. 2 ). 
     The storage compartment  3  in the shown embodiment of the apparatus has four discharge areas  15 ,  15 ′,  15 ″,  15 ′″. When the articles are discharged over the discharge areas  15 ,  15 ′,  15 ″,  15 ′″ in a uniform sequence, a satisfactory levelling of the articles  2  (see  FIG. 2 ) in the storage compartment  3  is achieved. 
     The degree of filling of the individual discharge areas  15 ,  15 ′,  15 ″,  15 ′″ is detected by a level measuring means  14 ,  14 ′,  14 ″,  14 ′″ for each discharge area  15 ,  15 ′,  15 ″,  15 ′″. In the shown embodiment, the level measuring means  14 ,  14 ′,  14 ″,  14 ′″ are disposed higher than the uppermost level of the articles  2  in the storage compartment  3 . The risk of damage to the level measuring means  14 ,  14 ′,  14 ″,  14 ′″ due to contact with the articles  2  is thereby minimised. 
     On  FIG. 2 , the articles  2  in the storage compartment  3  are shown at a low filling degree. There are a different number of articles  2  on the different discharge areas  15 ,  15 ′,  15 ″,  15 ′″. The reason for this may be that the customers primarily have taken articles  2  out from the discharge areas  15 ′ and 15″. By comparing the filling degrees in the discharge areas  15 ,  15 ′,  15 ″,  15 ′″ based on measurements performed by the level measuring means  14 ,  14 ′,  14 ″,  14 ′″, the control means (not shown) of the machine will prioritise filling discharge area  15 ′ until it has the same degree of filling as discharge area  15 ″. The two discharge areas  15 ′ and 15″ are then filled until they have the same filling degree as discharge area  15 . After which the three discharge areas  15 ,  15 ′ and 15″ are prioritised until all discharge areas  15 ,  15 ′,  15 ″,  15 ′″ are provided the same degree of filling. The apparatus  1  will then distribute the articles  2  over the discharge areas  15 ,  15 ′,  15 ″,  15 ′″ in a uniform sequence until the filling degree is 100% for all discharge areas  15 ,  15 ′,  15 ″,  15 ′″ in the storage compartment  3 . 
       FIGS. 3 and 4  show isometric views of the apparatus  1  from two different angles. 
     The apparatus  1  has a conveyor  4  with a support surface  5  for an article  2  (see  FIG. 5 ). The conveyor  4  is longitudinally displaceable so that it may distribute articles  2  (see  FIG. 2 ) over the discharge areas  15 ,  15 ′,  15 ″,  15 ′″ (see  FIG. 2 ). 
     A drive means for longitudinal displacement  6  of the support surface  5  of the conveyor is connected with a set of driving sprocket wheels  19 . In the shown embodiment, the support surface  5  of the conveyor is disposed on a slide  11 . The slide has two open sides transversely to the direction of movement with free edges  12 ,  13  (see  FIG. 5 ). An article  2  will leave the slide  11  over these free edges  12 ,  13 . The slide  11  has a U-shaped cross-section, but other cross-sections may also be used. The advantage of the U-shaped cross-section is that the articles  2  only can leave the slide over the edges at each end. 
     The conveyor  4  includes an endless conveyor means  10  in the form of a chain  20  at each side of the slide  11  which runs around a number of other sprocket wheels  21 . The slide  11  is fastened at each side to a chain link by an adapter  22 . The two chain links are disposed diagonally opposite each other. The endless conveyor means  10  both indicates a guide for the slide  11  and a connection between the drive means for longitudinal displacement  6  and the support surface  5 , and thereby the slide  11 . 
     The conveyor  4  is vertically displaceable as the chain  20  runs around three middle sprocket wheels  23  at each side. The slide  11  is elevated from a second height to a first height during passage of the three middle sprocket wheels  23 . This function is used in connection with welding film bags where the support surface  5  is elevated such that an article  2  is fully supported and the film web relieved thereby, such that cutting off a film bag is avoided during welding. In the shown embodiment, the drive means for longitudinal displacement  6  coincides with the drive means for vertical displacement  9  of the support surface  5  of the conveyor. 
     The conveyor  4  furthermore includes a pushing off means  7  which in the shown embodiment is an arm  24  which by rotating about a shaft  25  connected with a drive means for inserting  8  the pushing off means  7  can be inserted in the path of the article. The pushing off means  7  is oriented perpendicularly to the direction of movement of the conveyor and thereby that of the slide. 
     In the shown embodiment, the conveyor  4  has two pushing off means  7 —one at each side of the centre of the apparatus. Both arms  24  are connected to the same shaft  25  such that they both pivot down by activating the drive means for inserting  8  the pushing off means  7 . 
     The conveyor  4  is surrounded by a frame  26  on which the above components are attached. 
     Outside the frame  26  are provided level measuring means  14  in a number corresponding to the number of discharge areas. In a preferred embodiment of the invention, there are four level measuring means  14 ,  14 ′,  14 ″,  14 ′″. 
       FIGS. 5-13  show different sequences as seen from above during performance of the method according to the invention. Sequences for discharge on discharge areas  15 ″ and  15 ′″ are shown (see  FIG. 2 ). From that the skilled in the art may derive discharging over the remaining discharge areas. 
     On  FIG. 5 , an article  2  is disposed on the support surface  5  of the conveyor on the slide  11 . This is an initial position for the method. The slide  11  is at its first height. This is step A of the method. 
       FIG. 6  shows the slide  11  with the article over the discharge area  15 ″. The pushing off means  7 , which is an arm  24 , is inserted in the path of the article. The article  2  has just contact with the arm  24 . This is step B of the method. 
     On  FIG. 7 , the displacement of the slide  11  is continued. The article  2  which is retained by the arm  24  is discharged over one edge  12  of the slide in the discharge area  15 ″. This is step C of the method. 
     On  FIG. 8 , the empty slide  11  is on its way back to the initial position for collecting a further article  2 . This is preparation to step D of the method which is a repetition of steps A-C with selection of discharge area  15 ,  15 ′,  15 ″,  15 ′″ among the accessible discharge areas in a controlled sequence. 
       FIG. 9  shows the slide  11  with an article  2  where the slide is on its way to discharge area  15 ′″. This is during performance of step B of the method. The pushing off means  7 , which is the arm  24 , is in a position where it is outside the path of the article. 
       FIG. 10  shows the slide  11  with the article  2  over the discharge area  15 ′″. The arm  24  is introduced in the path of the article. The article  2  has just contact with the arm  24 . The conveyor  4  changes direction of displacement. This is the end of step B of the method. 
     On  FIG. 11 , the displacement with the changed direction is continued. The article  2 , which is retained by the arm  24 , though on another side of the latter in relation to discharge over the discharge area  15 ″ as on  FIG. 7 , is discharged over the other edge  13  of the slide in the discharge area  15 ′″. This is step C of the method. 
     The slide  11  then continues longitudinal displacement towards the initial position for repeating the method. 
       FIG. 12  shows the apparatus  1  with the conveyor  4  lifted to a first height where a film bag is supported for welding. 
       FIG. 13  shows the apparatus  1  with the conveyor  4  lowered to a second height after cutting off the article  2 . 
       FIGS. 14-15  show the apparatus  1  with the conveyor  4  which here comprises a slide  11  and the pushing off means  7 , which here is an arm  24  which by rotation about a shaft  25  can be inserted in the path of the article. 
     On  FIG. 14 , the arm is at a position outside the path of the article, while on  FIG. 15  it is at a position within the path of the article where pushing off occurs by the continued displacing of the slide past the arm  24  in one and the other longitudinal direction, respectively, depending on which side out of the plane relative to  FIG. 15  discharge is desired. 
       FIG. 16  shows an alternative embodiment of the apparatus  1  where the conveyor  4  includes an endless conveyor means  10  in the form of a conveyor belt  26  having free edges  12 ,  13  in parallel with the direction of movement of the conveyor. The pushing off means  7  is oblique relative to the direction of movement of the conveyor. In the shown embodiment, the apparatus  1  has two discharge areas  15 ,  15 ′. These may be served by means of one pushing off means  7 . 
     The article  2  will be pushed over one  12  and the other  13 , respectively, free edge of the conveyor belt, depending on its direction of movement, as the article  2  is acted on by an oblique resulting force due to the oblique orientation of the pushing off means  7 . 
     This embodiment of the invention enables use of only one apparatus in even relatively wide storage compartments as the discharge areas are laid out in two rows, one at each side of the conveyor  4 .