Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
  • B65H—HANDLING THIN OR FILAMENTARY MATERIAL, e.g. SHEETS, WEBS, CABLES
  • B65H31/00—Pile receivers
  • B65H31/32—Auxiliary devices for receiving articles during removal of a completed pile
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
  • B65H—HANDLING THIN OR FILAMENTARY MATERIAL, e.g. SHEETS, WEBS, CABLES
  • B65H2301/00—Handling processes for sheets or webs
  • B65H2301/40—Type of handling process
  • B65H2301/42—Piling, depiling, handling piles
  • B65H2301/422—Handling piles, sets or stacks of articles
  • B65H2301/4225—Handling piles, sets or stacks of articles in or on special supports
  • B65H2301/42256—Pallets; Skids; Platforms with feet, i.e. handled together with the stack
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
  • B65H—HANDLING THIN OR FILAMENTARY MATERIAL, e.g. SHEETS, WEBS, CABLES
  • B65H2301/00—Handling processes for sheets or webs
  • B65H2301/40—Type of handling process
  • B65H2301/42—Piling, depiling, handling piles
  • B65H2301/426—Forming batches
  • B65H2301/4262—Forming batches by inserting auxiliary support as defined in B65H31/32
  • B65H2301/42622—Forming batches by inserting auxiliary support as defined in B65H31/32 and using auxiliary means for facilitating introduction of the auxiliary support
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
  • B65H—HANDLING THIN OR FILAMENTARY MATERIAL, e.g. SHEETS, WEBS, CABLES
  • B65H2406/00—Means using fluid
  • B65H2406/30—Suction means
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
  • B65H—HANDLING THIN OR FILAMENTARY MATERIAL, e.g. SHEETS, WEBS, CABLES
  • B65H2406/00—Means using fluid
  • B65H2406/30—Suction means
  • B65H2406/35—Other elements with suction surface, e.g. plate or wall

Definitions

• the invention relates to a method and a device for changing pallets for sheet stacks with continuous conveyance of sheets to the stacking point.
• Such methods and devices are known from the prior art. For example, single sheets of paper, foil, plastic or the like are used under sheets. understood that have a flat shape.
• sheet stack is understood to mean collections of sheets lying one above the other.
• stacking point is understood to mean the point at which the sheet stack is formed from the sheets that are conveyed.
• individual sheets which were formed, for example, by a cutting device by cutting off a running web, are continuously, ie continuously, conveyed to a stacking point at stacking stations and are stacked there to form sheet layers or sheet stacks.
• stacks of sheets with a defined number of sheets must be transported away from the stacking location for further processing.
• the sheets are stacked on pallets educated. This means that when the sheet stack is transported away, the sheet stack on the pallet or together with the pallet is removed from the stacking point. Due to the continuous conveyance of the sheets to the stacking point, the filled pallet must be removed and an empty pallet brought to the stacking point without unduly disturbing the stacking of the sheet stack.
• a known method for carrying out such a pallet change with continuous conveyance of sheets to the stacking point is known from DE 36 1 6 470 C2.
• the method disclosed there also shows the closest prior art.
• a number of sheets are first stacked at the stacking point to form a first sheet stack on a first pallet.
• a separating finger is then inserted from the rear side of the sheet stack in the conveying direction of the sheet between the first sheet stack and the sheets subsequently conveyed.
• This separating finger is now lowered more slowly than the first stack of sheets, so that a gap is formed between the sheets conveyed on the separating finger and the first stack of sheets.
• a first jaw is now inserted into this gap.
• the separating finger is then removed from the gap, raised again to the top of the stack of the sheets that have been fed in, and then pushed again from the rear side between the sheets that follow and the sheet stack on the first clamping jaw.
• the separating finger is again lowered more slowly than the first clamping jaw with the stack located thereon, so that a further, second gap is formed between the first clamping jaw and the sheet located on the separating finger.
• a second jaw is inserted into this second gap. Now the stack of sheets located between the first and the second jaw is clamped between the jaws by moving the jaws towards each other.
• the first pallet with the first stack of sheets is then lowered below the sheet stack clamped by the clamping jaws, so that a gap is formed below the stack of sheets clamped by the clamping jaws, into which an auxiliary table can be inserted.
• the pallet is transported away with the first sheet stack.
• a new pallet is placed under the auxiliary table.
• the Auxiliary table pulled back out of the gap below the sheet stack held by the clamping jaws, so that the sheet stack held by the clamping jaws can be lowered onto the pallet arranged below the auxiliary table.
• the clamping of the sheet stack clamped by the clamping jaws is released by increasing the distance between the clamping jaws.
• the upper jaw must be raised slightly since the lower jaw is directly adjacent to the empty pallet. Subsequently, the lower jaw can first be pulled out of the gap between the empty pallet and the previously clamped sheet stack and then the upper jaw from the gap above the previously clamped sheet stack. Then the cycle starts again.
• the object of the present invention is therefore to create a less complex device.
• the advantages of the invention are in particular that, due to the invention, it is no longer necessary to clamp a stack of sheets. Rather, due to the invention, the sheet is sucked onto the separating jaw, so that no force is required on the sheet stack or on the individual sheets in the stacking direction. In addition, thanks to the invention, the clamping jaws become superfluous, which represents a considerable simplification of the method and also of the device operating according to such a method.
• the invention makes use of a special property of a sheet stack which, due to the precision of today's cutting devices, practically forms a closed, almost smooth surface on its side surfaces. This fact enables such a sheet stack to be sucked in from the side.
• a preferred embodiment of the method according to the invention is characterized in that, in the method according to claim 1, the generation of the gap between the first stack of sheets and the subsequent sheets is effected by the separating finger being slower against the stacking direction of the first Sheet stack is lowered than the first sheet stack itself. In this way, the gap is generated in a simple manner.
• a further preferred embodiment of the method according to the invention has the step of taking the separating fingers out of the gap simultaneously with or after introducing the separating jaw into the gap created by the separating finger.
• This embodiment makes it possible, for example, that the separating finger does not have to be guided in a recess in the separating jaw. Alternatively, however, it is possible to guide the separating finger in a recess in the separating jaw so that the separating jaw can be pushed into the gap while the separating finger is still in the gap.
• a particularly preferred embodiment of the invention is characterized in that openings are provided in the separating jaw facing the following bends, through which the subsequent bends are sucked in, by means of which gas, preferably air, is sucked in through these openings.
• the separating jaw can be designed, for example, as a hollow body, in which hollow body a vacuum is generated.
• the hollow body is then also provided with openings through which the hollow body can be connected to the suction side of a blower or another vacuum source.
• the separating jaw sucks the bottom sheet on its underside. This floor is additionally fixed.
• Another particularly preferred embodiment of the invention is characterized in that, when the beginning of a new stack is formed from subsequent sheets in the effective area of the separating jaw, the back of this new stack is sucked in by the separating jaw.
• This suction form is preferred and can be provided as an alternative to suction from below.
• the suction of the back of the new stack can also be provided cumulatively to the suction of the underside in the area of the back of the new stack.
• the latter embodiment promises an additional and maximum fixation of the new stack on the separating jaw working in this way.
• the separating jaw is preferably designed as an angle.
• the separating jaw has two surfaces, preferably arranged at right angles, each having openings through which a negative pressure is generated in the area of these surfaces.
• One surface is arranged parallel to the plane of the arch, while the other surface is arranged parallel to the jerking of the new stack.
• a further preferred embodiment of the method according to the invention is characterized in that, during the introduction of the auxiliary table, at least one belt arranged on its surface is activated in such a way that the relative speed between the belt and the lowermost sheet of the subsequent sheets is essentially zero in this way.
• a particularly advantageous and particularly preferred embodiment of the invention is characterized in that gas, preferably air, is blown against the underside of the belt while the auxiliary table is being introduced. In this way, the friction between the auxiliary table and the belt is reduced. It is particularly preferred if the belt arranged on the surface of the auxiliary table is designed as a cloth in order to avoid a relative speed of the auxiliary table top and bottom sheet.
• FIG. 1 to 10 show an embodiment of a method according to the invention in the form of ten schematic snapshots of the device according to the invention which carries out the method according to the invention
• Fig. 1 shows schematically a device 1 for changing pallets for sheet stacks with continuous demand from sheets to the stacking point.
• the device 1 has a conveyor belt 2. Sheets 4 are conveyed to a stacking station 6 on the conveyor belt 2.
• the stacking station 6 is in the conveying direction limited by a front converter 8 serving as a stop for the sheets conveyed to the stacking station 6.
• the stacking station 6 is delimited by a schematically illustrated, wall-like rear converter 10.
• the front converter 8 and the rear converter 10 run vertically.
• the feed conveyor 2 runs horizontally.
• the stacking point 6 is delimited at the bottom by a horizontally arranged pallet 12.
• the pallet 1 2 is - as indicated by the arrow 1 4 - lowerable to enable the upper edge 1 6 from sheets 4 already stacked on the pallet 1 2 to always remain at the same height, ie relative to the conveying plane of the conveyor belt 2 remains unchanged.
• the lowering means required to lower the pallet 1 2 are not shown in the drawing.
• the front converter 8 has through holes 1 8.
• the through holes 1 8 connect the front side 20 of the front converter 8 to a rear side 22 of the front converter 8.
• a cavity 24 is provided on the rear side 22 around the area in which the through holes 1 8 open.
• a vacuum can be generated in the cavity 24 by pumping means, not shown.
• the rear straightener 1 0 has recesses which are not visible and through which a separating finger 26 and a separating jaw 28 can reach the area of the sheet stack 30 already stacked on the pallet 1 2.
• the separating finger 26 is moved with the aid of a schematically indicated drive 32.
• the separating finger 26 can be moved both in the downward direction indicated by the arrow 14 and in the opposite direction, and also in the direction of the sheet stack 30.
• the separating finger 26 can be moved independently of all other parts of the device 1.
• the separating finger 26 has a base plate 34 which, in the basic position of the separating finger 26 shown in FIG. 1, runs parallel to the rear converter 10. At the end 36 of the base plate 34 of the separating finger 26 facing the feed conveyor 2, a separating plate 38 forming the actual separating finger 26 is attached perpendicular to the base plate 34.
• the separating jaw 28 like the separating finger 26, is designed as an angle.
• the separating jaw 28 also has a base plate 40 running parallel to the rear converter 10.
• a nose 42 is arranged on the base plate 40 at the end facing away from the conveyor belt 2. The nose 42 initially extends from the base plate 40 perpendicular to the base plate 40, the nose 42 being rounded at its front end. In the section of the nose 42 running perpendicular to the base plate 40, through-holes 46 are provided in the wall 48 of the nose 42.
• holes 46 in the wall 48 of the nose 42 connect the surface 44 of the nose 42 with a cavity 50 within the separating jaw 28.
• a negative pressure can be generated, so that air from the outside in through the openings 46 in the wall 48 the cavity 50 is sucked in.
• an excess pressure can be generated in the cavity 50, so that air is blown out through the bores 46 in the wall 48 of the nose 42.
• the negative pressure or the excess pressure in the cavity 50 is provided by pumping means, not shown.
• a second cavity 52 is provided behind the base plate 40 of the separating jaw 28.
• the second cavity 52 can also be placed under negative pressure. This negative pressure can be brought about by the same pumping means that also provide the negative pressure in the cavity 50. With the help of the negative pressure in the cavity 52, negative pressure can be generated on the surface 54 of the base plate 40 of the separating jaw 28 by sucking air from the outside into the cavity 52 through holes 56 in the base plate 40 of the separating jaw 28.
• auxiliary table 58 also shows a schematically represented auxiliary table 58.
• the auxiliary table 58 runs parallel to the feed belt 2.
• a schematically illustrated cloth 60 is movably mounted on the auxiliary table 58.
• the auxiliary table 58 can be moved in the direction indicated by the arrow 62 parallel to the sheets 4 stacked in the sheet stack 30. Simultaneously with the movement of the auxiliary table 58 in the direction of the arrow 62, the cloth can be moved on the auxiliary table 58 at the opposite, but the same amount in the direction of the arrow 64.
• the combination of auxiliary table 58 and cloth 60 can thus be moved such that a point x on the cloth 60 remains spatially fixed during the movement of the auxiliary table 58.
• FIG. 1 shows the basic state of the device 1 or of the method according to the invention.
• a predetermined number of sheets 4 are first stacked in a controlled manner by a control device (not shown) to form a sheet stack 30 on the pallet 1 2. This is done by requesting an interrupted flow of sheets 4 with the aid of the conveyor belt 2 to the stacking station 6 against the front converter 8.
• the pallet 1 2 is lowered by lowering means (not shown) in order to leave the leading edge 1 6 unchanged relative to the conveyor belt 2 conveyor plane
• the separating finger 26, the separating jaw 28 and the auxiliary table 58 are in the positions shown in FIG. 1. Neither a vacuum nor an excess pressure is present in the cavity 50 or in the cavity 52. In the embodiment shown in FIG. 1, no negative pressure is likewise generated in the cavity 24 of the front converter 8
• the separating finger 26 is moved from the rear side in the direction of the feed belt 2 into the stream the requested sheet 4 pushed. 2 separates the finished first sheet stack 30 upwards and separates the subsequent sheets 4 from the finished first sheet stack 30. Immediately after the separation finger 26 is inserted between the finished first sheet stack 30 and the subsequent sheet 4, the separating finger becomes 26 parallel to the lowering of the pallet 1 2 (arrow 1 4), as indicated by the arrow 66, lowered.
• the lowering of the separating finger 26 is slower than the lowering of the pallet 1 2. All other components of the device 1 are unchanged from their state shown in FIG. 1.
• a gap 68 shown in FIG. 3 is formed between the first sheet stack 30 and the sheets 4 which are further requested by the feed conveyor 2 and which reach the stacking point 6 in the gap thus formed 68 between the sheet stack 30 and the subsequent sheet 4, the separating jaw 28 is inserted.
• the separating jaw 28 with its base plate 40 comes into contact with the back 70 of the new stack of sheets 4, which has now been stacked up, and which has been retained by the separating finger 26 relative to the sheet stack 30.
• the top 44 of the nose 42 comes into contact with the bottom 72 of the bottom of the sheet 4 above the Trennfi ⁇ gers 26.
• the separating finger 26 is pulled out of the gap 68, so that the state shown in FIG. 4 results.
• the separating jaw 28 is also lowered parallel to the lowering of the separating finger 26 according to arrow 66 (see arrow 74). All other components of the device 1 are still in an unchanged state.
• a negative pressure is generated both in the cavity 50 and in the cavity 52 of the separating jaw 28.
• air is sucked into the cavity 52 through the openings 56 in the base plate 40 of the separating jaw 28.
• a negative pressure is generated on the surface 54 of the base plate 40, which sucks any air still between the sheets and fixes the back 70 of the new stack 76 of sheets 4 conveyed on the base plate 40.
• a negative pressure is also generated in the cavity 24 of the front converter 8. Air is thus sucked through the through holes 1 8 in the front device 8 into the cavity 24. This also creates a vacuum on the front side 20 of the front converter 8 in the area of the through bores 1 8. With the help of this negative pressure, air is sucked out between the sheets and the ends of the sheets 4 lying at the front in the conveying direction of the feed belt 2 are drawn against the front converter 8, thus preventing the front ends 78 from sinking onto the first sheet stack 30.
• the separating finger 26 is moved downward along the first sheet stack 30 on the pallet 1 2 according to the arrow 14.
• the separating finger 26 thus first reaches the position shown in FIG. 5 and then the position shown in FIG. 6 below the plane of the auxiliary table 58.
• a further method step is shown in FIG. 6.
• the auxiliary table 58 is moved into the gap 68, which is now further enlarged, while the negative pressures in the cavities 50, 52 and 24 are maintained unchanged, according to arrow 80.
• the negative pressure in the cavity 24 ensures that the underside 72 of the bottom sheet 4 of the new stack 76 does not fall onto the auxiliary table 58 or onto the cloth 60 running backwards on the auxiliary table counter to the direction of movement 80.
• the movement of the cloth 60 (see arrow 64 in FIG. 1) which is directed backwards in terms of amount with the same speed component as the auxiliary table 58 (arrow 80) will result in a relative movement between the underside 72 and the cloth 60 avoided.
• a light and jerk-free sliding of the cloth 60 on the auxiliary table 58 is ensured by an air film which is generated by compressed air emerging from openings in the auxiliary table 58.
• the blowing out of the air from the auxiliary table 58 is indicated by the arrows 82.
• the auxiliary table 58 reaches the position shown in FIG. 7. Simultaneously with the retraction of the auxiliary table 58 into the enlarged gap 68, the auxiliary table 58 is lowered in parallel with the separating jaw 28 according to arrow 84, so that it is further ensured that the upper edge 16 of the stacked sheets remains unchanged relative to the feed belt 2.
• the complete first sheet stack 30 is transported away together with the pallet 1 2.
• a new pallet 86 is brought up to the auxiliary table 58 from below.
• the negative pressure in the cavity 24 of the front converter 8 had already been released in order not to hinder a further lowering of the new stack 76.
• the blowing out of air from the auxiliary table 58 is stopped at this time, as shown in FIG. 8.
• the blowing out of air from the auxiliary table 58 can be continued until the auxiliary table 58 has been retracted from the position shown in FIG.
• FIG. 9 shows the next step in which the new pallet 36 is brought to the position left by the auxiliary table 58 according to FIG. 8. This means that the distance between the underside 72 of the lowermost sheet 4 from the new stack 76 and the new pallet 86 is reduced to a minimum. Simultaneously with the approach of the new pallet 86 to the new stack 76, the separating jaw 28 is pulled out of the gap 68 between the new stack 76 and the new pallet 86 according to the arrow 88 in FIG. 9 and the stack 76 is placed thereon, as it is shown in Fig. 1 0.

Landscapes

• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Sheets, Magazines, And Separation Thereof (AREA)
• Stacking Of Articles And Auxiliary Devices (AREA)
• Pile Receivers (AREA)
• Pallets (AREA)

Applications Claiming Priority (3)

Publications (2)

Family

ID=7912016

Family Applications (1)

Country Status (11)

Families Citing this family (25)

Family Cites Families (13)

• 1999
  • 1999-06-21 DE DE19928367A patent/DE19928367A1/de not_active Withdrawn
• 2000
  • 2000-05-23 DE DE50011914T patent/DE50011914D1/de not_active Expired - Lifetime
  • 2000-05-23 PT PT00940263T patent/PT1196344E/pt unknown
  • 2000-05-23 WO PCT/EP2000/004689 patent/WO2000078657A1/fr active IP Right Grant
  • 2000-05-23 EP EP00940263A patent/EP1196344B1/fr not_active Expired - Lifetime
  • 2000-05-23 CN CNB008092893A patent/CN1218863C/zh not_active Expired - Fee Related
  • 2000-05-23 AT AT00940263T patent/ATE313509T1/de not_active IP Right Cessation
  • 2000-05-23 AU AU55252/00A patent/AU773902B2/en not_active Ceased
  • 2000-05-23 ES ES00940263T patent/ES2252015T3/es not_active Expired - Lifetime
  • 2000-05-23 CA CA002375238A patent/CA2375238C/fr not_active Expired - Fee Related
• 2001
  • 2001-12-20 US US10/022,840 patent/US6481952B2/en not_active Expired - Fee Related
  • 2001-12-20 ZA ZA200110492A patent/ZA200110492B/xx unknown

Non-Patent Citations (1)

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