JP4132160B2 - Spiral stretch wrapping machine - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a spiral stretch wrapping machine, and more particularly to an improvement of a rotating ring type spiral stretch wrapping machine.
[0002]
[Prior art]
A ring having an inner diameter that is sufficiently larger than the plane dimension of the article to be wrapped is rotatably supported on a lifting frame that moves up and down along the pillar, and a film supply device is attached to the ring, and the ring is driven and rotated by a motor. Rotating ring type spiral stretch wrapping machine that spirally wraps around the side of the object to be packaged does not require rotating heavy load on the rotating table like the conventional rotating table type. As described above, since the heavy inverted L-shaped arm is not suspended from the frame and rotated, there is no need to use a heavy balance weight or a robust and expensive bearing, and thus the entire apparatus can be reduced in weight. There is an advantage that the film supply device can be rotated at a speed twice as high as the above.
[0003]
In addition, it is possible to attach cutting means for the film end portion of the film, means for locking one cut end of the film on the package, and means for clamping the other cut end to the lifting frame. Ascends and descends with the film supply device, and the relationship between the two is always kept the same. Therefore, the film can be cut and the cut end can be locked regardless of the position of the film supply device in the vertical direction. For example, the film can be wound from the upper end to the lower end of the package, and again to the upper end, and vice versa. Alternatively, it can be wound only one way from top to bottom or from bottom to top. Furthermore, there is also an advantage that the film can be wound around the side surface of the package in a headband shape at one place or a plurality of places.
[0004]
However, since it is difficult to externally supply power to the film supply device that is attached to the ring and is rotating, there is a problem that a method for applying tension necessary for stretch packaging to the film is limited.
[0005]
That is, in the case of the brake roller system (see reference numerals 14 to 17 in FIG. 1 of the Japanese Utility Model Publication No. 63-23283), the brake roller system is limited to the one having a magnet brake using a permanent magnet. Electricity generated by a dynamo (15) attached to a film supply device (12) as shown in FIG. 10 of the roller pre-stretch method disclosed in Japanese Patent No. 40682 or as shown in FIG. 10 of Japanese Patent Application No. 9-134538 Thus, it is limited to a powered pre-stretch method in which the motor (12f) is rotated to forcibly drive the stretching rollers 12c and 12d.
[0006]
On the other hand, as shown in FIG. 7 and FIG. 8, when a stretched film that is fed out from a powered pre-stretch film supply device at a constant speed is wound around a quadrangular prism-shaped package, the package and the film Variations in the tension applied to the film occur repeatedly between the supply devices (see Japanese Patent Application No. 6-097363, FIGS. 6 and 7), and cause the film to break or the package to be deformed during the packaging process. It was.
Further, in order to provide a means for avoiding this (for example, the invention described in the specification of the above-mentioned application) on the rotating film supply apparatus, a stable power supply for control is a prerequisite.
[0007]
[Problems to be solved by the invention]
The present invention has been made in view of such circumstances, and the problem is that the pair of stretching rollers are forcibly driven without supplying power to the film supply device mounted on the ring, and the number of rotations is externally applied. It changes each time depending on the signal, and changes the film supply amount from the film supply device (corresponding to the change in the required amount of film feeding from the package to be repeatedly generated when the rectangular column-shaped package is stretch-wrapped). It is an object of the present invention to provide a rotating ring spiral stretch wrapping machine having a structure that can be used.
[0008]
[Means for Solving the Problems]
In order to solve the above-described problems, the spiral stretch wrapping machine of the present invention is provided with one of a pair of rings (first ring) that is rotatably supported by a lifting frame that moves up and down along a pillar. And a film supply device comprising a pair of stretching rollers connected so that the downstream roller rotates faster at a set ratio than the upstream roller. The other ring (second ring) receives the external input signal and changes the speed to drive forward and / or reverse, and the rotation (movement) of the ring is a pair of stretches. Means for transmitting to any one of the rollers is provided.
[0009]
The apparatus of the present invention further includes a conveyor for carrying in and out the object to be packaged, a film cutting means on the elevating frame, a means for locking the end of the cut film near the object to be packaged on the object to be packaged, and It can be set as the automatic spiral stretch packaging machine provided with the means to clamp the edge of the film near the film winding.
[0010]
As a driving means for rotating the first ring and the second ring, as shown in the embodiment, a driving endless belt applied to the outer periphery of these rings or an inner surface of the ring is pressed by a plurality of guide rollers. A drive endless belt may be used, but the outer periphery and / or inner periphery of these rings may be covered with a material having a large coefficient of friction, and a drive friction roller may be pressed against these outer periphery or inner periphery.
[0011]
Alternatively, the ring itself may be an external meshing gear or an internal gear and driven by a pinion connected to a driving source. Further, instead of using the ring itself as an external meshing gear or an internal gear, a chain or a timing belt may be attached to the outer periphery or the entire inner periphery of these rings.
[0012]
Further, as a means for transmitting the rotation of the second ring to the rotation shaft of one of the pair of stretching rollers, it is attached to either the second ring or one of the pair of stretching rollers (as in the embodiment). Even if the pulley is connected with an endless belt, or when the pulley is directly pressed against the outer periphery or inner periphery of the second ring, the second ring itself is engaged with the outer gear or the inner gear as described above. In the case of a gear, a pinion may be attached instead of the pulley, and the pinion may be meshed with teeth provided on the outer periphery or inner periphery of the second guide ring.
[0013]
[Action]
In the apparatus of the present invention, the film supply device attached to the ring is rotated around the package by rotating the first ring supported by the elevating frame that moves up and down along the pillar, and the film supply The stretch film is stretched between a pair of stretching rollers that are incorporated in the apparatus and connected so that the downstream roller rotates faster than the upstream roller at a set ratio at all times, and tension is applied to the package. The effect | action of winding around the side wall of a spiral is achieved.
[0014]
Further, at that time, receiving the input signal from the outside, changing the speed of the second ring forward and / or reverse, and transmitting the rotational motion to one of the rotation shafts of the pair of stretching rollers, In addition to increasing and decreasing the film feeding speed by the stretching roller group in accordance with the speed increase immediately after the first ring (that is, the film supply device) starts rotating and the speed immediately before the stop, When stretch wrapping, the effect of changing in response to the change in the required film feeding speed from the side of the package to be repeatedly generated is also achieved.
[0015]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, although one Example of the spiral type stretch packaging machine of this invention is described with reference to drawings, this invention is not limited to this.
FIG. 1 is a perspective view of a spiral stretch wrapping machine according to an embodiment of the present invention, FIG. 2 is a perspective view of essential parts of the apparatus of FIG. 1, and FIG. 3 is a cross-sectional view taken along the line AA ′ of FIG. 4 is an elevational view of the film gripper and the swing arm mounted on the lifting frame as seen from the direction of arrow B in FIG. 2, and FIG. 5 is a diagram for explaining the operation of the film gripper and the swing arm in FIG. In the schematic plan view, the second ring and its accessories are not shown for easy understanding of the drawing. FIG. 6 is a schematic system diagram for explaining a control method of the driving means of the second ring. In order to make the drawing easy to see, the film gripper and the swing arm are not shown.
[0016]
In the figure, reference numeral 1 is a lifting frame, 2 is a portal frame, 2a is a pillar, 3 is a conveyor, 4 is a ring assembly, 5 is a first ring, 6 is a second ring, 7 is a film supply device, and 8 is Film gripper, 9 is a swing arm, 10 is a package, 11 is a support bracket, 12 is a receiving roller, 13 is a guide roller, 21 is a sprocket, 22 is an endless chain, 23 is a shaft, 31 is a sensor, 51 is Endless belt, 52 is a motor, 53 is a roller, 61 is an endless belt, 62 is a driving means for the second ring, 62a is an endless belt, 62b is a guide roller, 62c is a tension roller, 62d is a motor, 71 is Winding support shaft, 72 is an upstream stretching roller, 73 is a downstream stretching roller, 74 is a pulley, 75 is a guide roller, 6 is a bracket, 91 is a film presser, 92 is a hot wire knife, 93 is an air cylinder, F is a stretch film or take-up of stretch film, P is a pulse generator, Q is a frequency converter, R is a servo amplifier, S is a sequencer It is.
[0017]
Referring to FIG. 1, a stretch wrapping machine according to the present embodiment includes a portal frame 2, an elevator frame 1 that moves up and down along a pole 2a of the portal frame, and a ring assembly supported by the elevator frame. 4 and a film gripper 8 and a swing arm 9 which are also attached to the elevating frame 1 and a (chain) conveyor 3 for carrying in and out the article 10 to be packaged.
[0018]
A pair of sprockets 21 and one endless chain 22 are attached to the gantry 2a of the portal frame 2 in order to raise and lower the elevating frame 1, so that the chains 22 of both gantry 2a are interlocked. Both sprockets 21 below the gantry 2a are connected by a shaft 23 and driven by a reversible (rolling) motor (not shown).
[0019]
The ring assembly 4 includes a first ring 5 and a second ring 6, and both the rings are rotatably connected to each other, and a film supply device 7 is attached to the first ring 5 by a bracket 76. As will be described later, the first and second rings 5 and 6 are driven and rotated by different driving means. In addition, a sensor 31 is provided on the side of the (chain) conveyor 3 and stops at a fixed position in order to stretch-wrap the articles to be loaded.
[0020]
With reference to FIG.2 and FIG.3, the raising / lowering frame 1 of the apparatus of a present Example, the ring assembly 4 supported by it, and these components are demonstrated.
A plurality of support brackets 11 for supporting the ring assembly 4 are attached to the elevating frame 1.
Referring to FIG. 3, a state where the lifting frame 1 and the ring assembly 4 and the first ring 5 and the second ring 6 are connected to each other will be described. A receiving roller 12 is provided at the lower end of the support bracket 11 of the lifting frame 1. A guide roller 13 is rotatably mounted just above the guide roller 13. The receiving roller 12 receives the second ring 6 from below, and the guide roller 13 rotates in contact with the side surface of the second ring 6.
Further, an endless belt 61 is hung on the vertical surface of the second ring 6, but the belt is not driven and the second ring 6 is not rotated by the belt.
[0021]
A roller 53 is attached below the vertical surface of the first ring 5, so that the first ring 5 slides on the horizontal plane of the second ring 6. In addition, an endless belt 51 is hung in the recess of the vertical surface above the first ring 5 and is driven by the transmission motor 52, and the first ring 5 rotates in one direction on the horizontal plane of the second ring 6. To do.
[0022]
As shown in FIG. 2, a film supply device 7 is attached to the first ring 5 with a bracket 76. The film supply device 7 includes a winding support shaft 71 that supports the film winding F, and an upstream stretching roller. 72 and a downstream stretching roller 73, and in order to stretch the stretch film and apply tension to the film, the downstream stretching roller 73 rotates at a constant rate faster than the upstream stretching roller 72. A gear having a selected number of teeth is attached and connected by a timing belt.
A pulley 74 is attached to the downstream stretching roller 73. The endless belt 61 wound around the outer periphery of the second ring 6 bypasses the periphery of the pair of guide rollers 75 and is also hung on the outer periphery of the pulley 74.
[0023]
Reference numeral 62 (FIG. 2) is a driving means for the second ring 6, and the endless belt 62a is pressed against the inner surface of the second ring 6 by a plurality of guide rollers 62b. Reference numeral 62c is a tension roller for maintaining the tension of the endless belt 62a, and reference numeral 62d is a drive motor. C. A motor that responds promptly to an external command, such as a servo motor, and can perform forward and reverse rotation and speed change is used.
[0024]
As shown in FIG. 4, the swing arm 9 has already been wrapped around the object to be packaged 10 with the heat ray knife 92 that cuts the film and the end of the cut single-sided adhesive stretch film on the object to be packaged. A film presser 91 is attached on the stretch film to adhere and lock. The swing arm 9 is pivotably mounted on the lifting frame 1 and is swung by an air cylinder (not shown). The hot wire knife 92 moves back and forth with respect to the stretch film by the air cylinder 93.
The lifting frame 1 is provided with a film gripper 8 that is opened and closed by an air cylinder (not shown).
[0025]
The attachment position of the film gripper 8 and the swing arm 9 on the elevating frame 1 is substantially the same as the position where the film supply device 7 attached on the first ring 5 rotates after a set number of times and then stops. Match.
The film gripper 8 may be a “film gripper device” described in Japanese Utility Model Registration No. 2509270. In the case of using a non-adhesive film, the swing arm 9 in the above-described embodiment may be, for example, Japanese Utility Model Publication No. 63. It is preferable to attach a heat sealer described in Japanese Patent No. 23283.
[0026]
Furthermore, in the apparatus of the present invention, as film cutting means, means for locking the end of the cut film close to the object to be packaged, and means for clamping the end of the film near the film take-up An apparatus having a mechanism described in JP-A-6-211200 can also be used.
[0027]
Next, an example of the operation of the apparatus of the present embodiment will be described. The apparatus of the present invention can perform the above-described various winding methods just by changing the control program, similarly to the conventional rotary stretch wrapping machine. When the article to be packaged 10 carried in by the conveyor 3 reaches just below the ring assembly 4, the sensor 31 automatically stops. At this time, the front end of the stretch film F unwound from the take-up of the stretch film attached to the take-up support shaft 71 of the film supply device 7 is sandwiched by the film gripper 8. Next, the elevating frame 1 is lowered, and when the lower end of the film take-up F slightly passes the upper end of the package 10, the motor 52 starts at a low speed and drives the first ring 5 via the endless belt 51. Rotate. The rotation of the first ring 5 rapidly increases and reaches a predetermined rotation speed. The film supply device 7 attached to the first ring 5 also rotates around the package 10 and stretches the stretch film F between the upstream stretching roller 72 and the downstream stretching roller 73, thereby the film. Is tensioned and wound around the package 10 in a spiral shape. (The operation of the second stretching roller and the speed of the film delivered by the pair of stretching rollers will be described later.)
[0028]
The elevating frame 1 descends along the gantry 2a, starts to rise when reaching the lower end of the article 10 to be wrapped, rises again to the height at which the first ring 5 starts to rotate, and the stretch film F becomes the article 10 to be wrapped. Wound in a cross spiral shape on the side of When the film supply device 7 reaches the height at which the rotation starts, the motor 52 decelerates and stops, the first ring also stops rotating, and the film supply device also stops at the original position before the rotation starts.
[0029]
Next, as shown in FIG. 5, the swing arm swings, and the film presser 91 presses the end of winding of the stretch film F against the side surface of the package 10, and the film course is moved to the film gripper 8. Change to pass under. Next, when the film gripper 8 is closed and the film is sandwiched, the hot wire knife 92 of the swing arm 9 is energized, the air cylinder 93 is actuated, the knife is pressed against the film F, and the film gripper 8 close to the package 10. Cut the stretch film F. When the elevating frame 1 further rises and stops at the initial height, the conveyor starts and discharges the package 10. As long as it is described above, these operations are not different from those of the conventional rotating ring spiral stretch wrapping machine.
[0030]
The operation and function of the second ring, which is a feature of the present invention, will be described below.
When the first ring 5 is driven and rotated by the motor 52, the film supply device 7 connected to the first ring 5 is also rotated by the bracket 76. At this time, if the second ring 6 is not driven by the driving means 62 and is stationary, the endless belt 61 is also stationary. In this state, the pulley 74 of the downstream stretching roller 73 which is a part of the rotating film supply device 7 is engaged with the stationary endless belt 61, so that it slides on the belt and is driven. Rotated. And since the upstream extending | stretching roller 72 is connected with the downstream extending | stretching roller 73 so that it may rotate slowly at a fixed ratio, the stretch film F is extended | stretched between both rollers, a tension | tensile_strength is provided and it is drawn.
[0031]
In this embodiment, only the first ring 5 is rotating and the second ring 6 is stationary, and the speed of the film fed from the film supply device 7 is the film feeding speed required by the package. In order to set the maximum value and slow down the film feeding speed, the second ring 6 may be rotated in the same direction as the first ring 5, and the second ring 6 may be rotated in the first ring 5. If the film is rotated at the same angular velocity in the same direction, the stretch film is stopped. In other words, if the speed at which the second ring 6 rotates in the same direction as the first ring 5 is appropriately controlled within the range from 0 to the same angular velocity as the first ring 5, the film supply amount from the film supply device ( It can be changed (in response to changes in the amount of film required to be delivered from the package).
[0032]
Further, as a case different from the above, the film fed out while the film supply device 7 makes one turn around the package in a state where only the first ring is rotating and the second ring is stationary. You may set length so that it may become substantially the same as the surrounding dimension of a to-be-packaged object. That is, if the film feeding speed that the film feeding device 7 feeds in the state where the second ring is stationary is set in accordance with the average film feeding speed required by the package, it is faster than this (average) speed. To feed the film at a high speed, the second ring 6 may be rotated in the direction opposite to that of the first ring 5. To feed at a low speed, the second ring 6 should be rotated in the same direction as the first ring 5. If the second ring is rotated at the same angular velocity in the same direction as the first ring, the feeding of the film can be stopped as in this embodiment. it can.
[0033]
Next, an example of a control method for shifting the drive motor 62d of the drive means 62 of the second ring 6 in accordance with the requested film feed amount from the package 10 will be described with reference to FIG.
The pulse generator P is driven and rotated by a motor 52 that drives the first ring 5, and transmits a predetermined number of pulse signals per one rotation of the first ring 5. This pulse signal is sent to both the frequency converter Q and the sequencer S. The pulse signal sent to the sequencer S is counted in the sequencer, and thereby the relative position between the film supply device 7 and the packaging object 10 is specified. When the position reaches a preset position, a signal for identifying the position is transmitted to the frequency converter Q.
[0034]
On the other hand, the frequency converter Q is preliminarily input with a ratio for converting a pulse signal directly input from the pulse generator P when a certain position identification signal is received from the sequencer S. The pulse signal directly input from the generator P is converted and output to the servo amplifier R, thereby shifting the drive motor 62d (servo motor).
[0035]
【The invention's effect】
As described above in detail, according to the present invention, the pair of stretching rollers is forcibly driven without supplying power to the film supply device attached to the ring, and the number of rotations is changed by an external signal each time, Rotation of a structure capable of changing the film supply amount from the film supply device (corresponding to the change in the required amount of film feeding from the package to be repeatedly generated when the rectangular column-shaped package is stretch-wrapped) A ring-type spiral stretch wrapping machine can be provided.
[Brief description of the drawings]
FIG. 1 is a perspective view of a spiral stretch wrapping machine according to an embodiment of the present invention.
FIG. 2 is a perspective view of a main part of the apparatus shown in FIG.
FIG. 3 is a cross-sectional view taken along the line AA ′ of FIG.
4 is an elevational view of a film gripper and a swing frame mounted on a lifting frame as seen from the direction of arrow B in FIG.
5 is a schematic plan view for explaining the operation of the film gripper and the swing arm of FIG. 4; FIG.
FIG. 6 is a schematic system diagram for explaining a control method of the driving means of the second ring.
FIG. 7 is a schematic plan view for explaining a process in which fluctuations in the required amount of film supply occur in each stage of the relative rotation in a stretch wrapping machine of a type in which the film supply device is rotated relative to the package. is there.
8 is a graph plotting fluctuations in the required film supply amount generated in each process of FIG. 7;
[Explanation of symbols]
1: Lifting frame, 2: Gate frame, 2a: Pillar, 3: Conveyor, 4: Ring assembly, 5: First ring, 6: Second ring, 7: Film feeder, 8: Film gripper, 9 : Swing arm, 10: packaged object, 11: support bracket, 12: receiving roller, 13: guide roller, 21: sprocket, 22: endless chain, 23: shaft, 31: sensor, 51: endless belt, 52: motor, 53: roller, 61: endless belt, 62: second ring driving means, 62a: endless belt, 62b: guide roller, 62c: tension roller, 62d: motor, 71: winding support shaft 72: upstream stretching roller, 73: downstream stretching roller, 74: pulley, 75: guide roller, 76: bra Tsu DOO, 91: film retainer, 92: hot wire knife, 93: air cylinder, F: winding a stretch film or stretch film, P: pulse generator, Q: the frequency converter, R: servo amplifier, S: sequencer.

Claims (2)

A driving means for rotating the ring is provided on one ring of a pair of rings that are rotatably supported by an elevating frame that moves up and down along the frame, and a film winding support mechanism and a downstream roller are provided. A film supply device comprising a pair of stretching rollers connected so as to rotate faster at a set ratio than the upstream roller is attached, and the ring is input to the other ring of the pair of rings. Drive means for receiving a signal and changing the speed to rotate forward and / or reverse, and means for transmitting the rotational movement of the ring to one of the rotation shafts of the pair of stretching rollers are provided. Spiral stretch wrapping machine. A conveyor for carrying in and out the article to be packaged, and means for cutting the film on the lifting frame, means for locking the end of the cut film near the article to be packaged, and film winding of the film 2. The spiral stretch wrapping machine according to claim 1, further comprising means for clamping the end portion closer to the end.

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