JP2013252866A - Packaging apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a packaging apparatus capable of suppressing a quantity of heat discharged from seal jaws being in a standby state and reducing power consumption.SOLUTION: In a bag manufacturing/packaging machine 1, when stopping the machine 1 due to trouble or the like, then, correcting the state etc. of a cylindrical film F, work can be performed only when seal jaws 54 and 74 are opened, thus, a first suspension mode is performed in which the seal jaws 54 and 74 are on standby without bringing the sealing surfaces 541 and 741 of the seal jaws into contact with each other. Besides, when stopping the bag manufacturing/packaging machine 1, not because of the own trouble of the machine 1 but because of the upstream machine or the downstream machine, there is no trouble even if the seal jaws 54 and 74 are closed, and thus, a second suspension mode is performed in which the seal jaws are on standby while bringing the sealing surfaces 541 and 741 of the jaws 54 and 74 into contact with each other.

Description

  The present invention relates to a packaging device, and more particularly, to a packaging device that performs a heat sealing operation to sandwich and seal an overlapping portion of packaging materials.

  A vertical bag making and packaging machine is widely used as a packaging device that fills and packs an object to be packaged such as food in the bag while manufacturing the bag.

  For example, in a vertical pillow bag making and packaging machine disclosed in Patent Document 1 (Japanese Patent Application Laid-Open No. 5-65144), a packaging material, which is a sheet-like film, is formed into a cylindrical shape by a former and a tube, and a vertical seal Means seal the stacked vertical edges of the cylindrical wrapping material. Then, after filling the inside of the cylindrical packaging material from the tube and sealing it across the upper part of the bag and the lower part of the succeeding bag by the horizontal sealing mechanism below the tube, the center of the horizontal sealing part is cut with a cutter. Disconnect.

  As the horizontal sealing mechanism, a mechanism is often employed in which a pair of sealing members called seal jaws opposed to each other across the conveyance path of the cylindrical packaging material are pressed against each other to heat and press the cylindrical packaging material. Each sealing jaw follows the cylindrical packaging material that is continuously conveyed while drawing a substantially D-shaped trajectory, thereby ensuring a sealing time.

  However, normally, each of the sealing jaws is energized continuously to the built-in heater so that the temperature is maintained at a predetermined temperature even while waiting without being operated. Therefore, the amount of heat given from the heater to the sealing jaw during this period is released into the atmosphere without contributing to the heat sealing operation, and wastes power.

  An object of the present invention is to provide a packaging device capable of reducing power consumption by suppressing the amount of heat released from a standby sealing jaw.

  A packaging device according to a first aspect of the present invention is a packaging device that performs a heat sealing operation in which a first seal member and a second seal member heated by a heater sandwich and seal an overlapping portion of packaging materials, A control unit for controlling the operations of the first seal member and the second seal member is provided. The controller brings the seal surfaces of the first seal member and the second seal member into contact with each other at a position away from the packaging material during the suspension period of the heat sealing operation.

  In this packaging device, the first sealing member and the second sealing member are in contact with each other, and the first sealing member is compared with the total heat radiation from the conventional sealing jaw that has opened the sealing surface. Further, it is possible to reduce the amount corresponding to the amount of heat released from the seal surface of each of the second seal members. As a result, power consumption is reduced.

  A packaging device according to a second aspect of the present invention is the packaging device according to the first aspect, and further includes a transport unit that transports the packaging material. The control unit controls the transport unit to move the packaging material by a predetermined distance in a direction opposite to the transport direction during the pause period of the heat sealing operation.

  In this packaging apparatus, the conveyance unit moves the packaging material in a direction opposite to the conveyance direction by a predetermined distance to avoid leaving the packaging material sandwiched between the first seal member and the second seal member. And thermal damage to the packaging material is prevented.

  A packaging device according to a third aspect of the present invention is the packaging device according to the first aspect, and further includes a transport unit that transports the packaging material. The first seal member and the second seal member perform a heat sealing operation on the packaging material sent from the transport unit. The controller brings the seal surfaces into contact with each other at a position where the first seal member and the second seal member are not used in the heat seal operation during the pause period of the heat seal operation.

  In this packaging apparatus, the operator can determine whether the operation has stopped due to an abnormal operation or is on standby by looking at the positions of the first seal member and the second seal member. Easy and convenient to use.

  A packaging device according to a fourth aspect of the present invention is the packaging device according to the first aspect, and when the control unit is in the first state when the heat sealing operation is paused, the control unit sets the first pause mode as a normal standby operation. Run. The first pause mode is a mode in which the first sealing member and the second sealing member are put on standby without bringing the respective sealing surfaces into contact with each other. Furthermore, when the pause of the heat sealing operation is the second state different from the first state, the control unit executes the second pause mode as the power saving standby operation. The second pause mode is a mode in which the seal surfaces of the first seal member and the second seal member are brought into contact with each other to stand by.

  In this packaging device, when the heat sealing operation stops and the heat sealing operation must be started immediately, the power saving standby operation conversely delays the disclosure time of the heat sealing operation to improve productivity. In such a case, the decrease in productivity can be suppressed by selecting the first pause mode in which the seal surfaces do not contact each other.

  Further, when the packaging device is stopped due to a trouble or the like of the packaging device to correct the state of the bag or the like, the operation cannot be performed unless the sealing jaws are open, so the first pause mode is executed.

  On the other hand, when the packaging device is stopped due to the influence of the upstream machine and the downstream machine, not the trouble of the packaging device itself, there is no problem even if the sealing jaw is closed, so the second pause mode is executed.

  The packaging apparatus which concerns on the 5th viewpoint of this invention is a packaging apparatus which concerns on a 4th viewpoint, Comprising: The 1st state contains the state which has stopped the driving | operation in order to correct the state of a packaging material.

  The packaging apparatus which concerns on the 6th viewpoint of this invention is a packaging apparatus which concerns on a 4th viewpoint, Comprising: The 2nd state includes the state which has stopped driving | operation by the factor which is not abnormality of a packaging apparatus.

  In the packaging device according to the present invention, in comparison with the total heat radiation from the conventional seal jaws in which the seal surfaces are opened by the contact of the seal surfaces of the first seal member and the second seal member with each other, The amount corresponding to the amount of heat released from the seal surfaces of the first seal member and the second seal member can be reduced. As a result, power consumption is reduced.

The perspective view of the bag making packaging machine concerning one embodiment of the present invention. The front view of the bag making packaging machine shown in FIG. The side view of a horizontal seal mechanism in the state where the arm member inclined 55 degrees with respect to the horizontal direction. The side view of a horizontal seal mechanism in the state where the arm member inclined 50 degrees with respect to the horizontal direction. The side view of a horizontal seal mechanism in the state where the arm member inclined 45 degrees with respect to the horizontal direction. The side view of a horizontal seal mechanism in the state where the arm member inclined 10 degrees with respect to the horizontal direction. The flowchart until selecting and performing either the 1st sleep mode and the 2nd sleep mode. The side view of the sealing jaw at the time of 1st sleep mode execution as normal standby operation. The side view of the seal jaw at the time of 2nd sleep mode execution as power saving standby operation.

  Embodiments of the present invention will be described below with reference to the drawings. The following embodiments are specific examples of the present invention and do not limit the technical scope of the present invention.

(1) Configuration of Bag Making and Packaging Machine 1 FIG. 1 is a perspective view of a bag making and packaging machine 1 according to an embodiment of the present invention. FIG. 2 is a front view of the bag making and packaging machine 1 shown in FIG. 1 and 2, a bag making and packaging machine 1 is a machine for bagging a packaged item such as a confectionery, a bag making and packaging unit 5 which is a main body unit for bagging a packaged item, and bag making and packaging. A film supply unit 6 for supplying a film F serving as a bag to the unit 5 is included. In addition, operation switches 7 are arranged on the front surface of the bag making and packaging unit 5. Further, the liquid crystal display 8 is disposed at a position where the operator of the operation switches 7 can visually recognize, and the liquid crystal display 8 shows the operation state of the bag making and packaging machine 1. A control unit 70 for transmitting and receiving signals to and from the liquid crystal display 8 is built in the back side of the panel on which the operation switches 7 are integrated.

(2) Detailed configuration (2-1) Film supply unit 6
The film supply unit 6 is a unit that supplies the sheet-like film F to the forming mechanism 13 of the bag making and packaging unit 5, and is provided adjacent to the bag making and packaging unit 5. A roll around which the film F is wound is set in the film supply unit 6, and the film F is fed out from this roll.

(2-2) Bag making and packaging unit 5
The bag making and packaging unit 5 includes a forming mechanism 13 for forming the film F fed in a sheet shape into a cylindrical shape, and a pull-down belt for conveying the tube-shaped film F (hereinafter referred to as the cylindrical film F) downward. A mechanism 14, a longitudinal sealing mechanism 15 that seals the overlapping portion of the tubular film F in the longitudinal direction, a lateral sealing mechanism 17 that seals the upper and lower ends of the bag by sealing the tubular film F in the lateral direction, And a support frame 12 that supports each of these mechanisms. A casing 9 is attached around the support frame 12.

(2-3) Molding mechanism 13
As shown in FIG. 2, the forming mechanism 13 has a tube 31 and a former 32. The tube 31 is a cylindrical member, and the upper and lower ends are open. In FIG. 2, the tube 31 is disposed at the central opening of the top plate 29 and is integrated with the former 32 via a bracket (not shown). An article to be packaged that is weighed from the computer scale 2 is put into the opening at the upper end of the tube 31. The former 32 is disposed so as to surround the tube 31. The shape of the former 32 is such that the sheet-like film F is formed into a cylindrical shape when passing through the gap between the former 32 and the tube 31.

  The former 32 is also fixed to the support frame 12 via a support member (not shown). Further, the tube 31 and the former 32 of the forming mechanism 13 can be replaced according to the size of the bag to be manufactured. Therefore, the forming mechanism 13 is detachable from the support frame 12.

(2-4) Pull-down belt mechanism 14
The pull-down belt mechanism 14 is a mechanism that conveys the tubular film F wound around the tube 31 while adsorbing it, and includes a belt having a driving roller and a driven roller adsorbing function.

(2-5) Vertical seal mechanism 15
The vertical sealing mechanism 15 is a mechanism that heats and vertically seals the overlapping portion of the cylindrical film F wound around the tube 31 against the tube 31 with a constant applied pressure. The vertical sealing mechanism 15 includes a heater and a heater belt that is heated by the heater and contacts an overlapping portion of the tubular film. A horizontal seal mechanism 17 is disposed below the vertical seal mechanism 15.

(2-6) Horizontal seal mechanism 17
FIG. 3A is a side view of the lateral seal mechanism in a state where the arm member is inclined 55 ° with respect to the horizontal direction. FIG. 3B is a side view of the lateral seal mechanism in a state where the arm member is inclined by 50 ° with respect to the horizontal direction. FIG. 3C is a side view of the lateral seal mechanism in a state where the arm member is inclined 45 ° with respect to the horizontal direction. FIG. 3D is a side view of the lateral seal mechanism in a state where the arm member is inclined by 10 ° with respect to the horizontal direction.

  3A to 3D, the pair of rotating shafts 51 and 71 are located on both sides of the bag of the tubular film F and rotate synchronously in opposite directions. The pair of arm members 52 and 72 are provided at both ends of the rotary shafts 51 and 71 in the longitudinal direction, and are fixed to the rotary shafts 51 and 71 so as not to rotate relative to each other. The arm members 52 and 72 are block-like members that are long in one direction and rotate together with the rotation shafts 51 and 71, and support the swinging members 53 and 73 and the air bleeding mechanisms 56 and 76.

  The pair of seal jaws 54 and 74 have heaters 54a and 74a (see FIG. 5A) inside. The heaters 54a and 74a heat the sealing surfaces of the sealing jaws 54 and 74 (surfaces opposed to each other during lateral sealing, see FIG. 5) 541 and 741, and a portion of the tubular film F sandwiched between the sealing jaws 54 and 74 is heated. It is designed to be heat sealed.

  As shown in FIGS. 3A to 3D, the seal jaws 54 and 74 are supported by outer portions of the swinging members 53 and 73. Therefore, the swinging members 53 and 73 and the seal jaws 54 and 74 rotate around the rotation shafts 51 and 71 in synchronization with the arm members 52 and 72.

  The pair of ironing portions 55 and 75 is a member made of an elastic material having a cross-sectional cross-section. Further, the squeezing portions 55 and 75 are on the front side of the seal jaws 54 and 74 and on the rear side of the air release mechanisms 56 and 76, that is, the seal jaws 54 and 74 and the air release mechanisms 56 and 76 in the orbit. It is arranged between. Further, the squeezing portions 55 and 75 are in contact with the film F before the sealing jaws 54 and 74 immediately before performing the lateral sealing, and from the sealing jaws 54 and 74 with a slight gap between them. Also move in the turning direction at a fast speed. This forcibly drops the packaging material remaining on the top of the bag to the lower side of the bag and avoids the waste of the packaging material from being caught in the portion of the film F that performs lateral sealing. Thus, the occurrence of a sealing failure can be suppressed.

  The pair of air vent mechanisms 56 and 76 mainly have a pair of left and right air vent pads (air vent members) 61 and 81.

(3) Operation of the bag making and packaging machine (3-1) Schematic operation The sheet-like film F sent from the film supply unit 6 to the forming mechanism 13 is wound around the tube 31 from the former 32 and formed into a cylindrical shape, It is conveyed downward by the pull-down belt mechanism 14 as it is. The film F is in a state where both ends are overlapped on the peripheral surface in the state of being wound around the tube 31, and the overlapped portion is vertically sealed by the vertical seal mechanism 15.

  The cylindrical film F that has been sealed vertically and has a cylindrical shape passes through the tube 31 and descends to the horizontal sealing mechanism 17. At this time, simultaneously with the movement of the tubular film F, a lump of the packaged material falls from the computer scale 2 through the tube 31. And in the horizontal sealing mechanism 17, in the state which the to-be packaged object exists in the cylindrical film F, the upper end of the bag and the lower end part of the upper bag of the bag in which the packaged object exists are sealed horizontally. .

  When the pair of sealing jaws 54 and 74 are driven as shown in FIGS. 3A to 3D, the upper end of the preceding bag and the lower end of the following bag are laterally sealed almost simultaneously. Simultaneously with the horizontal sealing, the preceding bag B and the subsequent cylindrical film F are separated from each other by a cutter (not shown) built in one of the sealing jaws.

(3-2) Operation of the lateral seal mechanism 17 In the lateral seal mechanism 17, the rotation shafts 51 and 71 rotate by rotating a turning motor (not shown), and the swing members 53 and 73 together with the arm members 52 and 72 are rotated. The sealing jaws 54 and 74, the ironing portions 55 and 75, and the air venting mechanisms 56 and 76 supported by these perform a turning motion around the rotation shafts 51 and 71.

  As shown in FIG. 3A, before the horizontal seal is performed, when the inclination of the arm members 52 and 57 with respect to the horizontal direction is 55 °, the swinging members 53 and 73 and the seal jaws 54 and 74 are moved relative to the arm members 52 and 72. And turned in the turning direction.

  Further, in the state shown in FIG. 3A, the air vent pads 61 and 81 of the air vent mechanisms 56 and 76 sandwich the article to be packaged already in the tubular film F so that the posture is not disturbed before sealing. It abuts on the surface of the tubular film F little by little from the lower side.

  Next, as shown in FIG. 3B, when the inclination of the arm members 52, 72 with respect to the horizontal direction is 50 ° (when the arm members 52, 72 are turned 5 ° from the state shown in FIG. 3A), the air vent pads 61, 81 are It is in contact with the film F on more surfaces than in the state shown in 3A.

  3C, when the inclination of the arm members 52, 72 with respect to the horizontal direction is 45 °, the air vent pads 61, 81 come into contact with the film F by the substantially lower half surface, and the tubular film F Hold the packaged items inside.

  3D, when the inclination of the arm members 52, 72 with respect to the horizontal direction is 10 °, the contact surface between the air bleeding pads 61, 81 and the tubular film F is the air bleeding pads 61, 81. It moves from the bottom to the top of the surface. A pair of squeezed portions 55 and 75 are cylindrical in order to force the article to be packaged present inside the horizontal seal portion of the cylindrical film F to be forced downward by squeezing the portion of the cylindrical film F to be laterally sealed. The film F begins to be sandwiched with a predetermined gap. And the front-end | tip part of a pair of ironing parts 55 and 75 squeezes the part which carries out the horizontal seal of the cylindrical film F below at a speed faster than the conveyance speed of the cylindrical film F.

  Further, the state shown in FIG. 3D is a state in which the sealing jaws 54 and 74 sandwich the tubular film F and start horizontal sealing. Immediately before the state shown in FIG. 3D is reached, the pair of rotating shafts 51 and 71 and the cams 57 and 77 slightly move so as to approach each other by a rotating shaft horizontal moving mechanism (not shown). As a result, the sealing jaws 54 and 74 are surely brought into contact with the tubular film F, and a desired temperature and pressure are applied from the sealing jaws 54 and 74 to the tubular film F, whereby the lateral sealing is performed.

(3-3) Operation of Sealing Jaws 54 and 74 when Operation is Stopped The built-in heaters 54a and 74a (the sealing jaws 54 and 74 are maintained at a predetermined temperature while waiting without being operated. The energization is performed continuously (see FIG. 5A). Therefore, the amount of heat given to the sealing jaws 54, 74 from the heaters 54a, 74a during this time is released to the atmosphere without contributing to the heat sealing operation, and power is wasted.

  Therefore, in this embodiment, the control unit 70 waits by bringing the seal surfaces 541 and 741 of the seal jaws 54 and 74 into contact with each other only when the stop state of the bag making and packaging machine 1 is stopped due to a predetermined factor. The second sleep mode is executed. The specific operation will be described below with reference to the flowchart.

  FIG. 4 is a flowchart until selecting and executing either the first pause mode or the second pause mode. In FIG. 4, the control unit 70 determines whether or not the sealing jaws 54 and 74 are stopped in step S <b> 1. When it is determined that the sealing jaws 54 and 74 are stopped, the process proceeds to step S <b> 2. Continues to determine whether or not the sealing jaws 54 and 74 are stopped.

  In step S2, the control unit 70 determines whether or not the stop state is the first state. The control unit 70 stores a condition for determining whether the stop state corresponds to the first state or the second state.

  For example, when the operator forcibly stops the operation of the tubular film F through the operation switches 7 to correct the state of the tubular film F, the control unit 70 receives an input from the operation switches 7. It determines with it being the 1st state by the trouble of the packaging machine 1. FIG.

  On the other hand, when the article to be packaged is not loaded from the computer scale 2, the notification signal is input to the control unit 70, so that the control unit 70 stops the sealing jaws 54 and 74, and this stop is made by bag making. Since it is not the trouble of the packaging machine 1, it determines with it being a 2nd state.

  The control unit 70 proceeds to step S3 when it is determined in step S2 that the stop is in the first state, and proceeds to step S4 when it is determined that the stop is not in the first state (is in the second state).

  In step S3, the control unit 70 executes the first sleep mode as the normal standby operation. The first pause mode is a mode in which the sealing surfaces 541 and 741 of the sealing jaws 54 and 74 are placed on standby without being brought into contact with each other. This is adopted when the work or the like of the cylindrical film F cannot be performed unless the sealing jaws 54 and 74 are open.

  On the other hand, in step S4, the control unit 70 executes the second sleep mode as the power saving standby operation. The second pause mode is a mode in which the sealing surfaces 541 and 741 of the sealing jaws 54 and 74 are brought into contact with each other to stand by. When the control unit 70 executes the second pause mode, the sealing surfaces 541 and 741 of the sealing jaws 54 and 74 are positioned away from the cylindrical film F in order to prevent thermal damage to the cylindrical film F. In contact with each other.

  For example, the control unit 70 reverses the pull-down belt mechanism 14 to move the tubular film F by a predetermined distance in the direction opposite to the transport direction, so that the tubular film F is separated from the seal surfaces 541 and 741. Of course, the present invention is not limited to this, and the control unit 70 may temporarily bring the sealing jaws 54 and 74 into a position where they are not used in the lateral sealing operation, and then contact the sealing surfaces 541 and 741.

  FIG. 5A is a side view of the seal jaws 54 and 74 when the first pause mode is executed as the normal standby operation. FIG. 5B is a side view of the seal jaws 54 and 74 when the second pause mode is executed as the power saving standby operation.

  In FIG. 5A, since the sealing surfaces 541 and 741 of the sealing jaws 54 and 74 are not in contact with each other, heat is released to the atmosphere via the sealing surfaces 541 and 741. Therefore, the first pause mode is used when the operation is stopped such that the work cannot be performed unless the seal jaws 54 and 74 are opened.

  On the other hand, in FIG. 5B, since the seal surfaces 541 and 741 of the seal jaws 54 and 74 are in contact with each other, the amount of heat released from the seal jaws 54 and 74 is the amount of heat released from the seal surfaces 541 and 741 in FIG. The corresponding amount is reduced.

(4) Features (4-1)
In the comparison with the total heat radiation from the conventional sealing jaws in which the sealing surfaces 541 and 741 are opened when the sealing surfaces 541 and 741 of the sealing jaws 54 and 74 are in contact with each other, The amount corresponding to the amount of heat released from the seal surfaces 541 and 741 can be reduced. As a result, power consumption is reduced.

(4-2)
In the bag making and packaging machine 1, when the second pause mode is executed, the pull-down belt mechanism 14 moves the tubular film F by a predetermined distance in the direction opposite to the conveying direction, so that the tubular film F moves to the seal jaws 54 and 74. The tubular film F is prevented from being thermally damaged without being left in a sandwiched state.

(4-3)
In the bag making and packaging machine 1, the control unit 70 can bring the sealing surfaces 541 and 741 of the sealing jaws 54 and 74 into contact with each other at positions not used in the lateral sealing operation when the second pause mode is executed. In this case, the operator can determine whether the operation has stopped due to an abnormal operation or is on standby by looking at the positions of the seal jaws 54 and 74, so that it is easy to start the next procedure and it is easy to use.

(4-4)
In the bag making and packaging machine 1, the power saving standby operation conversely delays the disclosure time of the heat sealing operation for a short pause when the horizontal sealing operation must be started immediately after the horizontal sealing operation stops. Since there is a possibility of reducing productivity, in such a case, the first pause mode in which the seal surfaces 541 and 741 are not brought into contact with each other is selected.

  Furthermore, even when the bag making and packaging machine 1 is stopped due to a trouble or the like and the state of the tubular film F is corrected, the operation cannot be performed unless the sealing jaws 54 and 74 are open, so the first pause mode is executed.

  On the other hand, when the bag making and packaging machine 1 is stopped due to the upstream machine and the downstream machine, not the trouble of the bag making and packaging machine 1 itself, there is no problem even if the sealing jaws 54 and 74 are closed. The second sleep mode is executed.

  As described above, according to the present invention, since heat dissipation can be obtained by suppressing heat radiation from the sealing surface of the sealing jaw, it is useful not only for a bag making and packaging machine but also for an apparatus for sealing with a film interposed therebetween. is there.

1 Bag making and packaging machine (packaging equipment)
14 Pull-down belt mechanism (conveyance unit)
54 Seal jaw (first seal member)
54a Heater 70 Controller 74 Seal jaw (second seal member)
74a Heater 541,741 Seal surface

JP-A-5-65144

Claims (6)

A packaging device that performs a heat sealing operation in which a first sealing member and a second sealing member heated by a heater sandwich and seal an overlapping portion of packaging materials,
A control unit for controlling operations of at least the first seal member and the second seal member;
The control unit makes the seal surfaces of the first seal member and the second seal member contact each other at a position away from the packaging material during a pause period of the heat sealing operation.
Packaging equipment. A transport unit for transporting the packaging material;
The control unit controls the transport unit to move the packaging material by a predetermined distance in a direction opposite to the transport direction during a pause period of the heat sealing operation.
The packaging device according to claim 1. A transport unit for transporting the packaging material;
The first seal member and the second seal member perform the heat sealing operation on the packaging material sent from the transport unit,
The control unit makes the seal surfaces come into contact with each other at a position where the first seal member and the second seal member are not used in the heat seal operation during a pause period of the heat seal operation.
The packaging device according to claim 1. The controller is
When the pause of the heat sealing operation is in the first state, as a normal standby operation, a first pause mode is performed in which the seal surfaces of the first seal member and the second seal member are waited without contacting each other,
When the rest of the heat sealing operation is in a second state different from the first state, a second power saving standby operation is performed in which the sealing surfaces of the first seal member and the second seal member are in contact with each other to wait. Run hibernate mode,
The packaging device according to claim 1. The first state includes a state where operation is stopped to correct the state of the packaging material.
The packaging device according to claim 4. The second state includes a state in which operation is stopped due to a factor that is not an abnormality of the packaging device,
The packaging device according to claim 4.

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