FR2628391A1 - ARTICULATION-REGROUP APPARATUS AND METHODS FOR COMBINING, STACKING, PACKAGING AND STABILIZING ARTICLES - Google Patents

Abstract

The invention relates to palletizing devices. It relates to an apparatus which comprises a device 36 for gripping articles 34 which are moved along a boom 40 movable vertically on a mast 46. In this way, layers of boxes 34 are stacked on a pallet placed on it. a turntable 12 and a plastic film is wound around the boxes when the latter are driven in rotation on the turntable 12. Application to the automatic palletizing of groups of articles.

Description

The present invention relates to apparatus for grouping articles,

and methods of grouping,

  Stacking, packaging and stabilizing articles.

  More specifically, the invention relates to an apparatus for grouping a stack of articles with the aid of a robot, intended to receive articles separated from a feed, to transfer them to a station for stacking articles. to which the articles are stacked on a "pull sheet" which is a base sheet, in a box with low sides,

  on a pallet or directly on the surface of the job post.

  pounding articles and then winding a film around

  stacked keys so that a stable bundled or palletized load is "built". As used herein, the term "palletizer" and derivatives such as "palletizing, palletizing, pallet" and the like

  are used to designate any type of grouping of ar-

  stacked articles, the articles being stacked on a pallet, on a surface formed by a sheet or on the surface of the

  turntable of the aggregating apparatus when

  a bottom sheet or pallet is used.

  In known palletizing systems, a product is normally advanced to a pallet

  on a support base. Each article or group of articles

  The palletized load elements are then placed on the pallet at a location such that the number of elements that can be stacked on a pallet is maximum, with also nesting test of the elements so that they give

  some stability to the load when it was fully

accumulated on the pallet.

  After stacking articles or elements to form a complete pallet, the pallet is then removed from the pedestal and transmitted to a packaging station comprising a web application machine, a packaging machine for retraction, stretch wrapping apparatus or other type of packaging apparatus. At this packing station, the palletized load is wrapped or surrounded by a band so that continuity and stability of the load are ensured. The apparatus or device described herein constitutes an advanced robotic battery stacking apparatus or palletizer which itself constitutes an improved palletizing assembly which includes a programmable material handling element which, for example, removes one or more items from stack on a

  feed conveyor or a feed location

  tation and then positions these items on a pallet or already palletized items. The programmed material handling element stacks the items to

  a previously assigned location on the pallet,

  a certain degree of stabilization of the load by interlocking or overlapping or stacking items placed on the pallet. This nesting is not a true nesting of stacked articles but rather an overlap of boxes stacked on each other so that straight columns are not

  formed by boxes or stacked items. In many

  In many cases, palletized loads do not have significant stability.

  An apparatus allowing the pallet apparatus

  robotization of winding a film of plastic material which facilitates the stabilization of the palletized load around the stacked pallet, is integral with the apparatus

  advanced palletizing robot.

  The robot palletizer comprises sensors or, alternatively, executes a pre-programmed sequence of operations controlling the palletizing apparatus to begin packing the palletizer.

  load at the level of the intermediate layers-the most

  before the pile reaches the final height and that

  the load is packed completely.

  A film feed source is supported by the palletizing apparatus and can move vertically as the film is unrolled, being guided by various rollers so that the accumulated articles on the pallet are wrapped when the pallet is "built" . One of the advantages of the invention is that the stacks or columns of boxes or articles can be made because the palletized load is wrapped at certain intervals during the construction of the palletized load so that the integrity of the stack is increased. The possibility of forming columns in piles and not nested batteries as in known palletizing devices, allows the use of the own mechanical strength of boxes or cartons for the formation of robust batteries consolidated and secured formed by the products. This obviously allows the use of a greater height of the piles, the formation of heavier loads, the denser loading of a pallet so that the use of the pallets is better, and corresponding advantages can be obtained, such as the reduction of shipping costs and especially the reduction of the deterioration of the contents of cartons due to the collapse

lower levels of the stack.

  Other features and advantages of the invention

  will be better understood by reading the description

  which follows, with reference to the accompanying drawings in which: Figure 1 is a simplified perspective of an apparatus according to the invention; Figure 2 is a plan view of the apparatus of Figure 1;

  FIGS. 2A to 2F are plan views of

  assemblies comprising input and output transformers;

  FIG. 3 is a diagrammatic plan view

  sensing the path of passage of a film in the apparatus;

  FIG. 4 is a schematic plan view of the

same in Figure 1;

  FIG. 5 is a schematic plan view of the

  same in Figure 1; Figure 6 is a graph showing different

  synchronization elements during a turn of the turntable

  ing; and Figure 7 is a perspective of a variant of a part of an apparatus according to the invention.

  The representation of Figure 1 indicates the arrangement

  general assembly of the palletizing apparatus and this figure is first described. Identical references of others

  figures designate the same elements.

  The palletizing apparatus 10 comprises three

  major components. These are the turntable which bears the general reference 12 and which can rotate at any desired speed, the robot palletizing apparatus 14 and the film elevator 16. Several secondary constituents

  of a preferred embodiment of palletizing apparatus

  are also represented. A food transporter 18

  Pallet entry or pallet entry is arranged near the turntable and transmits a pallet to the turntable on demand. When a pallet is fully loaded and

  packaged, it is moved to the evacuation transporter 20

  pallet cuation. The product received is directed towards the

  same palletizing by the carrier 22 of products.

  As previously discussed herein, the apparatus is intended to stack and package articles on different surfaces such as "pull sheets", base sheets, low side boxes and the like or even directly to the surface of

  turntable. A preferred embodiment may

  stack on a conventional pallet, although

  as good utility can be obtained during use.

  the device for stacking and packaging with other possibilities, for example on the surface of the turntable.

  In the case where a conventional pallet is not used

  it may be advantageous to eliminate, if necessary, the pallet carrier and possibly the transporter

Release.

  Logically, from the carrier 22 of

  a feed conveyor 24 in quantity

  is the first element which, in the course of

  operation of the palletising apparatus, is

  countered by an article or package such as 25 to be palletized. The box, package, or article such as may be any configuration allowing stacking for shipping or storage on a pallet, pull sheet, or the like on the surface of the turntable. For example, the device 25 may be a cardboard box, a metal box, a carton, a cardboard box whose upper part is open, a tray carrying a material, nested elements such as buckets, or even bags or flexible packaging of material, containers or pouches. The expression "device in a box" is not

  not intended to limit the invention and is used

  a generic term for stackable materials stacked on top of one another. Thus, in this specification, the term "boxed device" refers to

"boxes" or derivatives.

  The flow rate input conveyor 24 may have a rough-surfaced upper belt for separating the boxes as they are transmitted to the conveyor 22. The boxes may be aligned on one side of the input conveyor by an adjustable guide rail (not shown). The product carrier, also constituting a substation conveyor or an entry station, is a roller assembly

  carried out in a preferred embodiment. Two sets.

  At least one photoelectric sensor is used on this carrier. Each set 26a, 26b and 28a, 28b includes a first source element and receiver, carrying the

  suffix a, and a reflector, bearing a suffix b,

  seeing the light from the source to the receiver. This is a classic technology. Various types of sensors that may or may not require reflectors may be used in place of the previously mentioned photoelectric sensor assemblies. In this specification reference is made to photoelectric sensors and reflectors, but it is merely an example of a detector device that can be implemented within the scope of the invention. The first photoelectric sensor assembly 26 is used for counting the boxes reaching the post carrier. The second photoelectric sensor assembly is used to detect when the last of a set of boxes 34 has been placed on the carrier of the

workplace.

  A "set of boxes" 34 is constituted by the

  amount of boxes that must be accumulated before

  removal by the robotic palletizing device

  on a turntable bearing the general reference 12. A set of boxes 34 may comprise, for example, four boxes placed in mutual contact on the conveyor.

workstation.

  A cardboard stop which stops the boxes on the conveyor is marked by the reference 30. Other cardboard stops not shown can be placed under the support of the rolls and controlled if necessary so that spaces are formed between the boxes which

are accumulated.

  When a set of boxes 34 has been accumulated, the robotic palletizing apparatus can transfer them onto a pallet which is waiting for them on the turntable 12. The boxes which arrive upstream and which are not necessary for the formation of a set of boxes are stopped until the complete set of boxes has been picked up by the robot palletizer and has cleared the

carrier of the workstation.

  In a normal cycle, a pallet 32 or the equivalent of a pallet such as a sled, a "pull sheet", a platform forming a base sheet, a

  container or the like, is in position on the turntable

  ing. Obviously, in the case where the bundled load is to be built without pallet or base sheet, no pallet or the like has to be in position. The set of boxes 34 is then lifted by the gripping device 36 which may comprise a "hand" chosen from many existing types. Figure 1 illustrates the use of "palms" 38 two of which are located, one placed inward and the other outward. One of the palms is fixed and the other is movable and can be controlled by a pneumatic cylinder (or other maneuvering or closing device) so that the palms move closer to the set of cans 34 and clamp and grip the cans

  between the palms. The type of "hand" is determined by the

  and a large number of types of hands are known in the industry, including support hands from the lower part to several palms, for example ensuring vacuum clamping or clamping from the top and

  from below, etc. The hand can also be articulated or

  bile on its support around an axis perpendicular to

the axis of the arrow.

  The structure of the gripping device 36 is carried by cam rollers on an arrow 40. The rollers of the gripper device move, in the case of the upper rail, on rails 42 and 44 so that the gripping device 36 can move laterally from a location above the conveyor 22 to a particular location on the pallet

found on the turntable 12.

  The boom 40 is mounted on the mast 46 so that it can slide so that the boom can move vertically on the mast. In an example of a sampling and positioning device, the two axes obtained using the mast and the arrow are sufficient for the transfer of boxes or sets of boxes from a conveyor 22 to the pallet 32. the following. The hand 36, placed above the set of boxes 34, is lowered, the clamping members of the hand cause the tightening of all the boxes by the palms, the arrow rises on the mast, the device 36 of capture moves along the arrow 40, the arrow 40 down along the mast 46, the hand opens and deposits the set of boxes 34 on the pallet to a

  predetermined location. When returning to the initial position

  tiale, the palms of the gripping device 36 are open and spaced from each other, the arrow goes up above the pallet, the gripping devices 36 return along the arrow 40, the latter descends along mast 46 and the gripper is ready to grab another set of boxes. The palletizer is programmed in such a way that it starts the movement, that it ensures this displacement, that it modifies the speed and that it finds the position suitable for the palletization of the sets of

  boxes according to the desired predetermined pattern of stacking.

  When a palletized load has been partially constructed and stacked with a predetermined pattern, the partially palletized load may be partially wrapped with a film so that the stability of the partially palletized load is increased. The stacking design has traditionally been carried out in a form that attempts to maximize the number of boxes carried by the high pallet, with nesting boxes so that the stability and integrity of the box. palletized load

  increased. Often, some boxes need to be

  next to one axis of the pallet and that other boxes are aligned along a second axis. In the layer or the following level of boxes, the latter are aligned in

  opposite directions so that a certain nesting is obtained.

  It is rare that the boxes are stacked in vertical columns by the current palletizing devices. Although the strength of the columns is much higher when the boxes are stacked directly on each other and they can be arranged so that the most robust parts of the boxes, that is to say the corners, are stacked on each other from one box to another, the resulting column of great height is very

  unstable and totally unusable in practice. How-

  However, the invention allows efficient stacking in g columns.

  so that the apparatus according to the invention makes it possible

  palletized loads more stable and robust than

  those that have been formed so far.

  When a partial load has been stacked on a pallet or a pallet device, the partial load which can have only two layers of boxes (the package can be made when a single layer of boxes has been stacked on the pallet but this is not a preferred embodiment), the packaging operation begins under the control of the control device of the palletizing apparatus. The wrapping device, usually a plastic film having high hysteresis properties after initial stretching, known as a "shrink wrap" film, constitutes the device

  preferred packaging for the implementation of the apparatus

  lage. This wrapping device can be constituted

  by other types of film, for example a thermoformed film

  retractable, a polymeric film, a perforated film, a net, coated or uncoated paper, a tape, cover protectors such as bubble wrap, and other cover materials or the like. For convenience, the wrapping device is called

"film" in this memo.

  The film represented in the form of a roll 48 of film is carried by an elevating member carrying the reference

  16 (film distribution set or distribution set)

  of the wrapping device) which is mounted

  so that it can slide on a vertical track 50.

  A chain hoist is used for the lifting of the

  vateur. The chain 52 is attached to the elevator at both ends and passes around a motor (not shown) placed within the vertical support 54 for convenience. The film is threaded (see Figure 3) from the roller 48 and passes around a first roller

  main 56 then around a second primary driving roller

  58. These two rollers introduce an important tension

  aunt in the movie (called "pre-stretching"). The film then passes over an oscillating roller 60 which is mounted so that it is movable and adjusts the driving speed of the rollers 56 and 58, so that the speed of the main driving rollers can increase as the consumption of the film increases. and decrease when it decreases. The film 62, when it has left the pre-stretching head with the general reference 16, passes over the guide roller 64,

  on a first roller 66 with a guide arm and a

  cond roll 68 with guide arms which are both mounted on a guide arm 70. The film is then directed to

  the film clamping device or the wrapping device

  72 which is mounted on the turntable bearing the

general reference 12.

  The film guide arm 70 directs the film around the mast 46 and towards the film clamping member 72 mounted on the plate 12. In a preferred embodiment, the film guide arm is held in a fixed position but can being articulated so that it pivots about its point of attachment to the film elevator designated by general reference 16. If the guide arm is mounted in articulated form, a resistance exerted by a spring, a pneumatic cylinder or the like, opposing the pivoting, can be advantageous for the conservation of the tension of the film

to the clamping device 72.

  In a variant, an articulated guide arm, controlled by a motor of any type, under the action of gravity or by springs, can be programmed

  so that it is recalled from a first position to a second

  conde position with maintenance of tension in the film especially when it must be stretched and released. The provision of a pivoting guide arm allows adjustment and minimization of the elongation and then the

  relaxation of the film. We return to the description of the mode of

  preferred embodiment; the height of the guide arm and the length of the rollers of the guide arm are such that the length or height is sufficient for the passage of the film over its entire width when unrolled. For example, the

  The film may be approximately 50 cm wide, but

  Wider or narrower enveloping positives are commonly used. It is not uncommon that the film

  used has a width equal to or greater than 1 m or less

less than or equal to 25 cm.

  The plan views of Figures 2, 3 and 4 make it easier to

  understanding of the operation of the device.

  For example, in Figure 2, the turntable 12 is shown with at least a partial load of boxes already in position. The mat 46, the arrow 40, the gripping device 36, the product conveyor 22, the rollers have been removed from the figures for reasons of simplicity, the film elevator 16 is shown schematically. In

  in addition, the pallet feed conveyor 18 and the conveyor

  Pallet evacuation carrier 20 is shown with an empty pallet 32 and a fully palletized load 33 on the respective inlet and outlet conveyors.

  respectively. The important features that

  easily appear and can be more easily understood in FIG. 2 than in FIG.

  "lines of sight" of the third photo sensor assembly

  74a, 74b, and sensor assembly 98a, 98b

  photoelectric pallet detection. In addition, the posi-

  Brush 92 is shown in full lines for fixing the load, and dotted in its other position, the brush being pivotable away from

charging or approaching it.

  As noted elsewhere in this memo,

  the assembly 98 is a conventional assembly having a transmitter

  beam receiver such as 98a and a reflector such as 98b which returns the beam to the receiver, unless a pallet (or other element) stops the beam

  luminous. When the beam is stopped, the

  The palletizing machine knows that a pallet is in position and it can control the stacking of the boxes on the pallet. When a base or pull sheet is the surface on which the boxes are stacked, the photoelectric sensor assembly 98 may be

  replaced by a photoelectric sensor detection system

  A reflector or a manual or automatic switch or the like can transmit a signal to the controller so that it can start stacking the boxes. It should also be noted that the boxes can be stacked directly on the surface of the turntable so that they can be transported by a device cart.

tightening, if necessary.

  The third set 74a, 74b with photoelectric sensor

  also appears on this figure. This set of

  Tect the upper part of a layer of boxes. The

  The formed signal is used by the controller for setting the vertical limit upwards.

of the elevator 16.

  FIGS. 2 and 3 also represent the path of the film going from the elevator 16 to the seizing member 72 of the

  movie. In FIG. 3, the roll of film 48 from

  which film 62 is unwound is shown schematically

  in plan. Film 62 goes around a first and a second

  main drive roll 56 and 58 which are driven with a speed difference, in a preferred embodiment, which provides prior drawing of the

  film, before passing over a swinging roller 60 and a roller

  The guidewire 64. The film then passes on first and second guide arm rolls 66 and 68 and then reaches the film clamp 72 which is shown in FIG.

  its "rest" position (in the present embodiment)

  fere) in all figures except Figures 4 and 5.

  Figures 4 and 5 show intermediate steps

  example of a stacking and packaging cycle.

  In Figure 4, a packaging cycle has begun and the turntable has rotated 90 in a clockwise direction

  of a watch, for example, in a first cycle of winding

  LEMENT. The film 62 is held tight in the device 72 and it is noted that it is in contact with the corner of the stack of boxes carried by the turntable. When the turntable reaches the rest position, a coil has been formed around the stack of boxes. The cycle continues as described herein.

  Figure 5 shows the loading or position

  of an empty pallet. Like the device 72 of

  film ridge is normally vertically disposed at the end of full winding of a load and is in the "rest" position shown in Figure 2, the film clamp (with film 62) must be is

  spaced from the path of the pallet 32 when loaded.

  A possibility for this purpose includes rotating the turntable counter-clockwise by 90 as shown in this figure. It should be noted that the film 62 is stretched when the film clamp is in the position shown in the figure. The beam of the pallet detection photoelectric sensor 98a was cut when the pallet 32 moved further

  in position on the turntable.

  A packing cycle of a palletizer according to a preferred embodiment shown in Fig. 1 begins under the control of the palletizer controller when a signal is received by this apparatus and indicates that the The desired box height for the first wrapping cycle has been reached. Good machine performance and good integrity of the machine

  the stack are obtained when the first cycle of envelop-

  This is done after two layers of boxes have been

positioned.

  In the first cycle-of development, the film is

  maintained tight in the clamping device 72. The provision

  The seizure machine 36 has moved away from the pallet having the partial pile, during its cycle, and continues to describe its

  cycle so that it takes the following set of boxes

  as the first wrapping cycle is performed. Turntable 12 rotates clockwise from a home position (in top view), this position corresponding to position 0 and 360 in this preferred embodiment, so that the film is drawn from the roll of film 48. At a time close to the beginning of rotation rotating rotation, that is to say a little before, a little after or at the same time, the elevator 16 received a

  signal from the controller of the palletizer

  to move vertically in the vertical direction

  50. This upward movement of the elevator causes the opening of the lower switch 78. The upward movement of the elevator causes the spiral film to move along the pile of boxes placed on the pallet when the turntable continues to turn. The film is then wrapped around the stack while being held by

the clamping device 72.

  The first wrapping cycle continues until the palletizer detects the arrival at the top of the can top layer. In

  In general, the first wrapping cycle is carried out

  360 rotation of the turntable but more

  one turn may be advantageous in some applications.

  tions. The signal indicating that the upper layer of boxes has been reached comes from the photoelectric sensor 74a which transmits a light beam to a reflector 74b mounted on a vertical support or a reflector post. The

  reflector 74b is a continuous reflector of no.

  table mounted on the reflector pole, the length of which

  made it to match boxes of different heights. When the photoelectric sensor 72a detects the upper part of the boxes, it indicates it to the body of

  control of the palletizing apparatus so that the arrangement

  the film elevator drive can stop

  to raise the elevator. At this moment, the turntable

  continued to rotate until it returned to

  rest. The device 72 for clamping the film

holds the film in a tight position.

  Although the film elevator is normally set so that it stops going back to a place where the film does not exceed the top of the boxes placed on the

  pallet, it may be advantageous in some cases

  put the elevator up higher. For example, if the elevator reaches a point where the film is at cm above the top surface of the boxes, the film is stretched and can be pulled inward on the outer edges of the boxes. This may be advantageous for stack stabilization if the next set of boxes

  is then placed on this part of film turned towards the

  TER AL. When the turntable is back in position

  of rest, a stacking assembly starts to pile up from

  very many layers of boxes on the pallet. For example, it stacks two more layers of products and indicates the beginning of the cycle of envelopment. The second wrapping cycle

  and the following are a repetition of the first cycle of

  development, in a preferred embodiment, up to

  the entire height of the palletised load is at-

  color, the total height corresponding to the number of

  boxes that have been previously programmed into the

  control unit of the palletizer.

  When a fully stacked load has been accumulated on the turntable, the upper portion of the top layer boxes is detected by the third photoelectric sensor assembly 74 and the elevator ceases to raise the film roll so that it can not go over the top of the stack. This is a similar operation to the detection of cycles

spiral wound winding.

  As previously stated for the description of

  the interruption of the first wrapping cycle, the film can rise higher than the upper part of the upper layer of boxes so that the complete load of stacked articles can be better grouped. The film elevator can be programmed so that it passes slightly

  higher than the upper part of the boxes, either

  diatement either after several wraps have been

  formed at the top of the pile.

  When the spiral wrap film was applied

  all palletized load, a bundling wrap of the palletized load is desirable so that this load undergoes a better grouping, either

  strengthened and integrated. Although the envelopment

  realized during the first wrapping cycle and subsequent cycles ensures grouping and facilitates

  support of the load during stacking, allowing in particular

  building a load of stacked boxes

  in columns, among other advantages, packing work

  may or may not be sufficient for the integration of

  the palletised load is ensured.

  It may be desirable, in one variant, to complete the entire wrapping of the pallet load when the stack has been formed. In this case, instead of the progressive spiral wrapping, the control member maintains the wrapping head in horizontal position when the turntable performs one or more turns so that the stack is wrapped at this level. This can be done at various heights of the stack when it is under construction. This reduces the winding time after the load has been stacked because part of the winding can be performed

  during the "sampling" carried out by the

* lage. An additional wrap, in a mode of

  preferred embodiment of the invention may be realized

  in the following way. When the film elevator is in the up position on the vertical track 50 and when the photoelectric sensor 72 indicates that it does not

  should not rise higher, the control device of the

  The palletizing machine indicates to the turntable

  at least one complete revolution, three laps

  faction, while the elevator is held in position relative to the upper part of the load. When the

  number of laps has ensured the application of a

  the elevator is controlled so that it can descend along the vertical track 50 with a set speed while the palletized load continues to rotate.The elevator can be controlled to maintain its horizontal or vertical position. it goes down at a low speed so that a larger amount of film is applied to designated heights of the load or it can continue to descend so that a spiral wrap of the

  load is realized during its displacement.

  An intermediate sensor or switch 76, for example a microswitch or the like, indicates to the controller of the palletizing apparatus when the lower part of the elevator is just above the upper part of the clamping member 72 which, at this

  moment of the cycle, still squeezes the anterior edge of the film.

  When this intermediate switch 76 is closed, the control member of the palletizing apparatus indicates to the clamp member to move back and release the front edge of the film. When the clamping member has moved back to a position which is for example below the

  lower part of the first layer of boxes, the elevation

  16 can continue its descent and wrap the lower part of the palletized load with several layers

  of film, during several turns of the turntable.

  In a variant of the first cycle of enve-

  spiral or first or second rotational

  complete cycle of wrapping of the upper part of

  In addition, the film wrapping apparatus can position a portion of the film, of the order of a few centimeters, protruding from the film above the upper portion of the upper edge of the upper layer of the box. This gives better integrity for some types of stacked products. It is possible to use this technique for the intermediate levels of the spiral wrapping operation, but this technique is not the mode of

most advantageous realization.

  In some cases, it is desirable that the film be placed over the support pallet, the box

  lower or similar on which the articles are

  Battery. This ensures continuity between the support pallet and the articles so that the latter and the pallet are packaged together to a certain extent. This

  is not always necessary or desirable.

  We consider again the end of the cycle; the front edge of the film was quickly covered, at least partially, by the film wrapping the palletized load when the elevator reaches the lower section of the load. Although the anterior edge of the film is rapidly covered by rapid rotation of the turntable, it has been found that a stream of air directed towards the free anterior edge of the film is advantageous so that this anterior edge is held against the load up to that the film can be covered with subsequent layers. An air jet nozzle 76 which receives air from a supply (not shown) of the turntable, is mounted on this

last so that she plays this role.

  During the final turn of the turntable after the desired number of turns or wraps has been achieved, the

  The film must be placed in the clamping device before

  following palletization ration. This operation is

  in the final part of 180 of the rotation of the

  rotating water. The film clamps are in the retracted position at the beginning of the tightening cycle. After the turntable has rotated 180 during its final rotation, a signal is transmitted to the palletizing controller to extend the rear portion 84 of the film clamp. It should be noted that the device 72 for clamping the film is formed of two main clamping elements. These elements include an element

  82 and a posterior element 84. The previous element

  The invention is a robust member having a surface facilitating attachment, for example a rubber coating on the surface which is in contact with the film. The posterior element 84 is also a robust member having a surface ensuring a

  good hanging. When the film is placed between the

  anterior and posterior, it is firmly held until the clamping member is open (just before the elevator 16 reaches the vicinity of the member 72).

clamping film).

  When the posterior element 84 has been deployed in

  vertical position, the previous element is still in

  receding or horizontal in general, and further rotation of the turntable causes the rear member 84 to come into contact with the film between the palletized load and the film guide arm 70. The turntable continues to rotate and during this further rotation, the front member of the film clamp is deployed in position so that the film is clamped between the prior and

  posterior of the clamping device.

  The film is then clamped into the

  rage but is still fixed, in the form of a continuous sheet, the fully wrapped palletized load. It has been found that, for cutting the film, a heated rod hinged to intersect the path of the film ensures a clean cut of the film. Such a device for cutting or terminating a heated rod film is represented at 86 in

  recessed position on the turntable. The heating rod

  fairy is carried by a support that is mounted in form

  articulated at a first end and which can be

  maneuvered by a pneumatic cylinder (not shown).

  When the film has been cut by the heated rod or other film-terminating device such as a hot wire, knife or the like, the palletized load is

  completed and it can be moved away from the turntable.

  In a preferred embodiment, the turntable has a driven roll platform surface 88 which allows the palletized load to be evacuated to a pallet evacuation conveyor bearing the reference

general 20.

  However, it was found that before extraction of the

  palletised load of the turntable, it was desirable

  table, in some applications, that the posterior end

  the film is "smoothed" so that the trapped air is driven out and allows a better adhesion of the posterior part to the load. This posterior end of the film is normally bonded to the film placed on the palletized load because it has a tendency to "elastically recover" to a certain extent after being cut by the heating knife 86. Nevertheless, a possible step of the palletising process according to the invention. invention includes the "smoothing" of

  the end of the film, for example using a

  90 positive fixation. The latter shown in Figure 1 is in the form of a brush 92 carried by a post 94 and having a drive device 96 for rotating the brush 92 as the pallet exits the turntable to the conveyor 20. evacuation. The brush may be elastically biased against the palletized load near the posterior end of the film so that it smooths the posterior end of the film placed on the pallet. The fixing device can be of a

  one of several known types, for example a roller with

  smooth or hard surface side, an air jet directed towards the posterior end of the film, a fixed ramp which exerts pressure on the posterior portion of the film when it is transmitted to the pallet evacuation conveyor, or the like.

  In situations as indicated on the

  5, when the film 62 "relaxes" during the rotation of the turntable in the counterclockwise direction and is stretched again when the device 72

  tightening takes the position represented at 90, we have

  state that it was advantageous to adjust the preliminary stretching

  introduced into the film by the pre-stretching rollers

  alable, that is, the first and second primary rolls

  training center 56 and 58 so that the film

not excessively unwound.

  Fig. 6 is a graph showing how the rollers 56 and 58 are operated and stopped so that the film does not feed in excessive amounts. It should be noted that the driving rollers 56 and 58 are

  operation so that they remove the film from the

  water 48 under the control of the oscillating roller 60 which can move inward as indicated by the arrow of Figure 3 when a larger amount of film is needed. This is the current film unwinding process. However, when using a pre-stretch film, the film, after having undergone prior stretching

  between rollers 56 and 58, is "re-established" and

  it causes a pull of the oscillating roller 60 inwards and the initiation of the advance ensured by the rollers 56 and 58. This occurs of a set degree each time the film is not wound on the boxes, for example when

  the turntable is in the rest position.

  The graph in Figure 6 shows how

  pretensioning seems to stop working or is put

  in operation during the final rotation of the cycle of

  developing and inverting the turntable so that the pallet can be loaded. The controller receives limit switch signals which are arranged

  way they detect the position of the turntable.

  From point A to point B (the arrows indicate the direction of movement of the turntable),

  the pre-stretching assembly of the film is in operation

  This, in other words, ensures the film advance during this final rotation of the load and the turntable. At point B which corresponds to a rotation of about 330, the pre-stretching assembly ceases to function and eliminates the possibility of advance of the film (B to C). From C to D, the turntable rotates in a clockwise direction up to about 270 as indicated

  in FIG. 5, and the preliminary stretching assembly does not function

  not work. When the pallet is loaded, the turntable rotates in a clockwise direction and at an angle of about 330 (D to E) the pre-stretching assembly is stopped. The pre-stretching assembly is put back into operation for the duration of the end of the lap (E

at F).

  Figures 2A to 2F show diagrams of

  various installations associated with the pallet apparatus

  tisation. The operating principles of these variants are the same as those of the embodiment of FIG.

1, for the most part.

  FIG. 2A simply represents the inverse of the structure of FIGS. 1 and 2, the products being transmitted

  on the left side of the turntable (with reference to

rotation of the mast towards the arrow).

  Fig. 2B shows an installation having a pallet entry conveyor 104 which arrives on the turntable from the right thereof. In this embodiment, the carrier 22 of the products may be lifted to allow the pallets to be transmitted below. In this embodiment, the turntable

  may need to be rotated in the direction

  milking clockwise so that the film gripping member 72 does not come into contact with the pallet when

  is discharged from the tray to the evacuation conveyor 20.

palette.

  Figure 2C simply represents the inverse of the

provision of Figure 2B.

  Figure 2D is similar to Figure 2 but the positions of the pallet supply conveyor 18 and the pallet evacuation conveyor 20 simply

been reversed.

  Figure 2E simply represents the inverse of

diagram of Figure 2D.

  Figure.2F shows a palletizer with no pallet feed conveyor or

  pallet evacuation. The turntable 12 of the

  The palletizing device is served by a transport device such as a forklift or a pallet truck.

traction sheet handling.

  FIG. 7 shows a variant of the invention concerning the use of a short film clamping member 100. The other aspects of this embodiment are the same as in FIG. 1, except for the short film clamping member 100, additional film tightening roller 102 and the different position of lower switch 78 which is placed on its support at a position lower than that of the mode switch.

embodiment of Figure 1.

  In this embodiment, the clamping member 100

  of film has a length less than the width of the film 62.

  The latter is thus tightened as shown so that it

  passes through the jaws of the film clamp.

  The 16 film elevator descended so low on the way

  vertical 50, because of the low position of the

  78, that the film can rub against the upper face of the turntable. The tightening roller 102 guides the film over the surface of the turntable and therefore has

  tendency to tighten the film down.

  The advantage of this short clamping member 100 is that, during the initial windings on the lower layers of boxes, the elevator does not have to be raised so much as not to come into contact with the short film clamping member. only in the case of using a larger clamping member (Figure 1). This allows a greater winding at the bottom of the stacked boxes, and

  this may be advantageous in the case of certain loads.

  Of course, various modifications can be made by those skilled in the art stacking apparatus and grouping of a set of articles in the form of a bundled package, and processes that have just been described only to as non-limiting examples without

depart from the scope of the invention.

Claims (13)

  Apparatus for forming a stack of grouped articles, characterized in that it comprises: a turntable (12) for supporting the stack of articles, a palletizing apparatus (14) for stacking articles on the turntable, a device (16) for presenting a wrapping device to the turntable and a cutter device (86) for   cut the wrapping device.   2. Apparatus according to claim 1, characterized in that it further comprises:   a control member for causing rotation   rotating plate (12), the control member triggering the stacking of articles on the turntable, the control member triggering the presentation of the   wrapping device by the display device tion (16), and   the control device triggering the cutting of the disc   positive wrapping by the cutter device (86). 3. Apparatus according to claim 2, characterized in that the control member performs one of its functions   triggering at the same time as another of its func- triggers.   4. Apparatus according to claim 2, characterized in that the palletiser (14) comprises a vertical mast (46), a transverse boom (40) mounted so that it can move vertically on the mast, a grasping (36) supported by the arrow so that it   moves transversely, the input device can   to be positioned above the turntable and   above an area that is not occupied by the turntable. 5. Apparatus according to claim 4, characterized in that the device (16) for presenting the wrapping device comprises a unwinding device, a first and a second main driving roller (56, 58) for unwinding the device. wrapping device of the presentation device, and a film guiding arm (70) for facilitating the presentation of the device   wrapping on the turntable.   Apparatus for constructing a load of bundled individual articles, characterized by comprising: a turntable (12) for rotating and having   a support surface comprising a transmission device   port to support the load of individual bundled items,   an entry station (22) for accumulating articles   individual keys near the turntable, a mat (46) supported vertically near the turntable,   an arrow (40) carried on the mast and movable vertically   wedge along it, an input device (36) carried by the arrow and intended to grip the articles, this input device   may be placed above the entrance station and above the turntable,   a set of unwinding of a wrapping device   on the mast, this assembly being vertically movable calmly along the mat,   a device (72) for clamping a device for   an arrangement for retaining the wrapping device and mounted on the turntable, and   an envelope device guiding arm (70)   placed between the unwinding assembly and the device   for guiding the wrapping device   from the feed assembly to the turntable.   7. Apparatus according to claim 1, characterized in that the guide arm (70) is mounted on the assembly of   unwinding of the wrapping device.   8. Apparatus according to claim 1, characterized in that the turntable (12) supports a device (86) with cutting elements.   9. Apparatus according to claim 1, characterized in that it further comprises a device (90) for controlling the rear edge, placed near the turntable. 10. A method of grouping a stack of articles, characterized in that it comprises the following steps: the advance of an empty pallet on a turntable (12), the removal of a number of items stacking on a fixed conveyor (22), transporting the articles on the pallet,   repetition of the sampling and trans-   during a certain number of sampling and transport operations, driving the turntable (12) in rotation,   film advance from a roll of film to the   rotating drum when it rotates, and cutting the film after at least one turn of the board turning.   11. A method of stacking and wrapping a   seems of items on a pallet with a device of   development from a set of unwinding   wrapping so that the stability and integrity of the set of items carried by the pallet are   increased, characterized in that it comprises the following steps:   : the arrangement of the pallet on a turntable (12), the stacking of articles on the pallet, the rotational drive of the turntable (12)   so that the wrapping device is unwound from the seems to unwind,   positioning the film around the set of ar-   tics, and the interruption of the transmission of the device   wrapping the whole reeling.   12. A method of stabilizing a palletized set of boxes on a pallet, characterized in that it comprises the following steps: the collection of at least one box on a carrier (22)   tightening the box by a clamping device (36), lifting the clamping device and the box,   moving the clamping device to a location   above the pallet, the deposition of the box on the pallet, the repetition of the preceding steps until a predetermined number of boxes have been deposited on the pallet with formation of a palletized load , rotating the pallet by pulling a wrapping device from a wrapping-wrapping reel assembly, interrupting transmission from the wrapping device, and attaching the wrapping device to the palletised load.   Method according to claim 12, characterized   in that the pallet is rotated by a   rotating plate (12), and the turntable has a wrapping device clamping device (72) which holds the wrapping device close to the palette.