Packaging film piece forming mechanism and packaging apparatus

Abstract

A packaging film piece forming mechanism is a mechanism that allows formation of a plurality of packaging film pieces sequentially using a strip-shaped film including a plurality of regions to become the packaging film pieces and to be connected continuously to each other across a perforated line, in such a manner as to form each of the packaging film pieces from a head region at a head of the strip-shaped film among the regions. The packaging film piece forming mechanism comprises a chuck unit and a stopper unit. The chuck unit is a unit that includes chuck parts in a pair that chuck corresponding opposite ends of the head region in a width direction, and allows the chuck parts in a pair to move back and forth between a start position at which chucking of the head region is started and a release position separated from the start position toward a direction in which the strip-shaped film is drawable. The stopper unit is a unit that allows drawing of the strip-shaped film to be stopped by clamping the strip-shaped film.

Description

TECHNICAL FIELD

[0001] The present invention relates to a technique for forming a packaging film piece from a continuous strip-shaped film, and a packaging technique using the packaging film piece.BACKGROUND ART

[0002] The technique for forming a packaging film piece from a continuous strip-shaped film includes a generally-known technique by which the strip-shaped film is cut at a predetermined position using a cutting blade. As an example, Patent Literature 1 disclosures a technique by which a strip-shaped film is drawn by a predetermined length by grasping opposite sides of the film with an arm and thereafter a cutting blade is moved down, thereby cutting the strip-shaped film at a predetermined position and forming a packaging film piece having the predetermined length.CITATION LISTPatent Literature

[0003] Patent Literature 1: Japanese published unexamined patent No. 2021-116081SUMMARY OF INVENTIONTechnical Problem

[0004] According to the conventional technique using the cutting blade, however, maintenance (such as changing) of the cutting blade is required to be done regularly. Furthermore, in order to cut the strip-shaped film at the predetermined position, the predetermined position and a position to which the cutting blade is to be moved down are required to be aligned with each other correctly. To achieve this, a high-precision mechanism or high-precision control is required.

[0005] Furthermore, for cutting the strip-shaped film with the cutting blade, the strip-shaped film is required to be applied with tension to become free from a slack. In response to this, according to the technique disclosed in Patent Literature 1, tension is applied to the strip-shaped film using a roller that unwinds the strip-shaped film and the arm that draws the strip-shaped film. If the strip-shaped film is cut in this state, however, the strip-shaped film might be curled in a part having become a new head as a result of the cutting when the tension is lost by the cutting. The occurrence of such a curl makes it hard to grasp the strip-shaped film with the arm in preparation for next cutting, and this causes hindrance to continuous operation of a packaging apparatus.

[0006] Thus, in relation to a technique of forming a packaging film piece, the present invention is intended to achieve both improvement of maintenance performance and implementation of continuous operation.Solution to Problem

[0007] A packaging film piece forming mechanism according to the present invention is a mechanism that allows formation of a plurality of packaging film pieces sequentially using a strip-shaped film including a plurality of regions to become the packaging film pieces and to be connected continuously to each other across a perforated line, in such a manner as to form each of the packaging film pieces from a head region at a head of the strip-shaped film among the regions. The packaging film piece forming mechanism comprises a chuck unit and a stopper unit. The chuck unit is a unit that includes chuck parts in a pair that chuck corresponding opposite ends of the head region in a width direction, and allows the chuck parts in a pair to move back and forth between a start position at which chucking of the head region is started and a release position separated from the start position toward a direction in which the strip-shaped film is drawable and at which the head region is released from chucking. The stopper unit is a unit that allows drawing of the strip-shaped film to be stopped by clamping the strip-shaped film.

[0008] According to the above-described packaging film piece forming mechanism, the strip-shaped film can be drawn by moving the chuck parts in a pair to the release position with the head region of the strip-shaped film chucked by the chuck parts in a pair. On the other hand, the drawing of the strip-shaped film can be halted by clamping the strip-shaped film using the stopper unit. By performing both of these, it becomes possible to generate tension on the strip-shaped film. By using the resultant tension, it becomes possible to tear off the head region of the strip-shaped film along the perforated line at a boundary with a next region. In this way, it is possible to form the packaging film piece without using a cutting blade.

[0009] In the above-described packaging film piece forming mechanism, the stopper unit may be configured in such a manner that, when the stopper unit clamps the strip-shaped film, the opposite ends of the head region in the width direction protrude from the stopper unit to become ready to be chucked by the chuck parts in a pair.

[0010] A packaging apparatus according to the present invention comprises: the above-described packaging film piece forming mechanism; and a controller. The controller causes the chuck parts in a pair to chuck the head region of the strip-shaped film at the start position. Next, the controller causes the chuck parts in a pair to continue chucking of the head region and moves the chuck parts in a pair from the start position toward the release position. On the way of moving the chuck parts in a pair toward the release position, the controller causes the stopper unit to clamp a next region connected to the head region across the perforated line.

[0011] According to the above-described packaging apparatus, while drawing of the strip-shaped film is stopped by clamping the next region continuous with the head region, it is possible to pull the head region with the chuck parts in a pair. As a result, using tension generated on the strip-shaped film by the pulling, only the head region can be torn off along the perforated line at the boundary with the next region. The torn-off region becomes one packaging film piece.

[0012] In the above-described packaging apparatus, the controller may perform control as follows. On the way of moving the chuck parts in a pair toward the release position, the controller stops the chuck parts in a pair temporarily when the perforated line at a boundary between the head region chucked by the chuck parts in a pair and the next region entirely goes out of a clamping range where clamping is to be done by the stopper unit and then causes the stopper unit to clamp the next region. The controller thereafter restarts moving of the chuck parts in a pair, thereby tearing off the head region of the strip-shaped film along the perforated line at the boundary with the next region using instantaneous force generated at the time of the restart. According to this configuration, the strip-shaped film is broken easily along the perforated line by using the generated instantaneous force.

[0013] In the above-described packaging apparatus, the controller may perform control as follows. After causing the stopper unit to clamp the next region continuous with the head region chucked by the chuck parts in a pair on the way of moving the chuck parts in a pair toward the release position, the controller causes the stopper unit to continue a state of the clamping until chucking of the next region by the chuck parts in a pair is started. According to this configuration, after the next region becomes a new head region as a result of tearing-off of the head region, the next region is kept clamped by the stopper unit until it is chucked by the chuck parts in a pair. This makes it possible to reliably prevent a curl likely to occur at the head region of the strip-shaped film.

[0014] The packaging apparatus may further comprise a transport mechanism that transports a packaging target, and an affixing mechanism. The affixing mechanism is a mechanism that affixes the packaging film piece formed by the packaging film piece forming mechanism to the packaging target being transported by the transport mechanism.

[0015] More specifically, the transport mechanism may include a loader and an unloader movable closer to and farther from each other in a transport direction, and may be configured to allow formation of space at a position under the release position at which the packaging target is allowed to lie astride the space by moving the loader and the unloader farther from each other. The affixing mechanism may include a first press unit and a second press unit. The first press unit is a unit that allows the packaging film piece to be pressed against an upper surface of the packaging target to put the packaging film piece into a state where opposite ends thereof are suspended downward after the packaging film piece is released from chucking by the chuck parts in a pair at the release position. The second press unit is a unit that allows the opposite ends of the packaging film piece suspended downward to be pressed against a bottom surface of the packaging target.

[0016] According to this configuration, by moving the loader and the unloader farther from each other to form the space at a position under the release position, it becomes possible to expose the bottom surface of the packaging target lying astride the space. Moreover, while a central portion of the packaging film piece is placed on the upper surface of the packaging target by the first press unit, it is possible to guide smoothly the opposite ends of the packaging film piece to the bottom surface of the packaging target by the second press unit. This makes it possible to affix the opposite ends at the bottom surface of the packaging target.Advantageous Effects of Invention

[0017] According to the present invention, in relation to a technique of forming a packaging film piece, it is possible to achieve both improvement of maintenance performance and implementation of continuous operation.BRIEF DESCRIPTION OF DRAWINGS

[0018] FIG. 1A is a front view conceptually showing a packaging apparatus according to an embodiment, and FIG. 1B is a block diagram conceptually showing the packaging apparatus.

[0019] FIG. 2A is a perspective view conceptually showing a strip-shaped film used in a packaging film piece forming mechanism of a packaging apparatus, and FIG. 2B is a perspective view conceptually showing the packaging film piece forming mechanism.

[0020] FIGS. 3A and 3B are perspective views of a chuck unit of the packaging film piece forming mechanism. FIG. 3A shows a case where a chuck part is closed, and FIG. 3B shows a case where the chuck part is opened.

[0021] FIGS. 4A and 4B are perspective views of a stopper unit of the packaging film piece forming mechanism. FIG. 4A shows a case where a plate is separated from a stage, and FIG. 4B shows a case where the plate is adjacent to the stage.

[0022] FIG. 5 is a front view of the packaging apparatus showing a case where a loader and an unloader of a transport mechanism of the packaging apparatus are separated from each other.

[0023] FIG. 6 is a conceptual view showing a first press unit and a second press unit of an affixing mechanism of the packaging apparatus viewed from a transport direction.

[0024] FIG. 7A is a conceptual view showing the motion of the first press unit, FIG. 7B is a conceptual view showing a first phase of the motion of the second press unit, and FIG. 7C is a conceptual view showing a second phase of the motion of the second press unit.

[0025] FIG. 8 is a flowchart showing control processing performed by a controller of the packaging apparatus.

[0026] FIG. 9A is a perspective view showing the motion of the packaging film piece forming mechanism in order.

[0027] FIG. 9B is a perspective view showing the motion of the packaging film piece forming mechanism in order.

[0028] FIG. 9C is a perspective view showing the motion of the packaging film piece forming mechanism in order.

[0029] FIG. 9D is a perspective view showing the motion of the packaging film piece forming mechanism in order.

[0030] FIG. 9E is a perspective view showing the motion of the packaging film piece forming mechanism in order.

[0031] FIG. 9F is a perspective view showing the motion of the packaging film piece forming mechanism in order.DESCRIPTION OF EMBODIMENTS[1] Configuration of Packaging Apparatus

[0032] FIGS. 1A and 1B are a front view and a block diagram respectively conceptually showing a packaging apparatus according to an embodiment. As shown in these drawings, the packaging apparatus includes a packaging film piece forming mechanism 1, a transport mechanism 2, an affixing mechanism 3, and a controller 4. The configurations of these units will be described below in detail.[1-1] Packaging Film Piece Forming Mechanism

[0033] FIG. 2A is a perspective view conceptually showing a strip-shaped film 10 used in the packaging film piece forming mechanism 1 according to the present embodiment. As shown in this drawing, the strip-shaped film 10 is an elongated film with a plurality of regions Rf connected to each other continuously across perforated lines Pm. Here, each region Rf is a region to become a film piece (packaging film piece Qf) used for packaging of a packaging target 20 (such as a food container, see FIG. 5). The strip-shaped film 10 is coated with an adhesive applied in advance for allowing the packaging film piece Qf to be affixed to the packaging target 20. The adhesive is applied to a predetermined width along each of opposite edges of the packaging target 20, for example.

[0034] FIG. 2B is a perspective view conceptually showing the packaging film piece forming mechanism 1. The packaging film piece forming mechanism 1 is a mechanism for allowing formation of a plurality of the packaging film pieces Qf sequentially using the above-described strip-shaped film 10, in such a manner as to from each of the packaging film pieces Qf from a head region Rft at a head of the strip-shaped film 10 among the regions Rf (see FIG. 2A). The packaging film piece forming mechanism 1 includes a chuck unit 11 and a stopper unit 12.

[0035] The strip-shaped film 10 is in a roll shape by being wound around a core, for example (see FIG. 2A), and is drawn only by drawing force from the chuck unit 11 described below. In other words, the packaging apparatus according to the present embodiment does not always require a motor for unwinding the strip-shaped film 10. At the packaging apparatus according to the present embodiment, the strip-shaped film 10 is arranged in a manner allowing the strip-shaped film 10 to be drawn in the same direction as a transport direction Dx in which the packaging target 20 is transported by the transport mechanism 2 described later. The packaging apparatus is not limited to this but may be changed, as appropriate, to an apparatus with a motor for unwinding the strip-shaped film 10 secondarily in response to drawing of the strip-shaped film 10.Chuck Unit

[0036] FIGS. 3A and 3B are perspective views of the chuck unit 11. The chuck unit 11 includes chuck parts Fp in a pair and a sliding transport part Gp.

[0037] The chuck parts Fp in a pair are configured to allow chucking of corresponding opposite ends Rfa and Rfb (opposite ends in a width direction Dy, see FIG. 2A) of the head region Rft of the strip-shaped film 10 (see FIG. 9A). More specifically, each chuck part Fp includes an upper chuck structure 111 and a lower chuck structure 112, and is configured to be openable and closable by moving the upper chuck structure 111 and the lower chuck structure 112 vertically toward directions opposite to each other. In the drawings, FIG. 3A shows a case where the chuck part FP is closed, and FIG. 3B shows a case where the chuck part Fp is opened.

[0038] Still more specifically, at each chuck part Fp, the upper chuck structure 111 is composed of an L-shape block with a tip projecting downward and the lower chuck structure 112 is composed of an L-shape block with a tip projecting upward. These blocks are configured in such a manner that respective tip surfaces (planes) thereof come into surface-contact with each other when the blocks are closed. The described chuck part Fp can chuck a corresponding one of the opposite ends Rfa and Rfb of the head region Rft by clamping a part of the corresponding opposite end Rfa or Rfb not applied with the adhesive. If the adhesive is applied to a predetermined width along each of the opposite edges of the strip-shaped film 10, for example, a part of each of the opposite ends Rfa and Rfb internal to the predetermined width can be clamped with the L-shape tips.

[0039] Each chuck part Fp is configured in such a manner that, even when the chuck part Fp is intended to pull the strip-shaped film 10 by moving of the chuck part Fp described below after the chuck part Fp clamps the strip-shaped film 10 using the upper chuck structure 111 and the lower chuck structure 112, the chuck part Fp can keep a state of grasping the strip-shaped film 10, in other words, can prevent the strip-shaped film 10 from slipping and coming off. Still more specifically, force of clamping the strip-shaped film 10, frictional force at the tip surface, etc. are adjusted appropriately.

[0040] The sliding transport part Gp is configured to allow the chuck parts Fp in a pair to move back and forth between a start position Ps (see FIGS. 1 and 9A) at which chucking of the head region Rft of the strip-shaped film 10 is started and a release position Pt (see FIGS. 5 and 9F) separated from the start position Ps toward a direction (same as the transport direction Dx in the present embodiment) in which the strip-shaped film 10 is drawable and at which the head region Rft is released from chucking.

[0041] More specifically, the sliding transport part Gp includes a support 113 supporting the chuck parts Fp in a pair, and a guide 114 that moves the chuck parts Fp in a pair back and forth by causing the support 113 to slide. In the present embodiment, the guide 114 defines a direction in which it causes the support 113 to slide to be the same as the transport direction Dx.

[0042] Still more specifically, the support 113 is composed of a beam 113A extending in the width direction Dy and slidably mounted on the guide 114, and support arms 113B in a pair supporting the chuck parts Fp in a pair at predetermined height positions. The predetermined height positions mentioned herein are height positions at which the strip-shaped film 10 is allowed to pass through between the upper chuck structure 111 and the lower chuck structure 112 when the support 113 is caused to slide along the guide 114 with the chuck part Fp in an opened state.

[0043] In the present embodiment, the support 113 is configured to allow adjustment of a distance between the chuck parts Fp in a pair. More specifically, the support 113 is configured to allow the positions of the support arms 113B in a pair in the width direction Dy to be adjusted using a ball screw 113C. Still more specifically, the support 113 is configured to allow the support arms 113B in a pair to move toward directions opposite to each other in the width direction Dy by rotating a handle 113D with a hand to rotate a shaft of the ball screw 113C.

[0044] The guide 114 has a built-in ball screw (not shown in the drawings), and causes the support 113 to slide by rotating a shaft of this ball screw using a motor (not shown in the drawings). With this configuration of the guide 114, controlling a direction of rotation of the motor (forward direction and reverse direction) allows the support 113 to move back and forth in an axis direction of the ball screw. In the present embodiment, the guide 114 is arranged in such a manner that the axis direction of this ball screw becomes the same as the transport direction Dx.

[0045] Furthermore, in the present embodiment, a range of sliding of the support 113 is defined in such a manner as to allow the chuck parts Fp in a pair to move back and forth between the start position Ps and the release position Pt described above. This range of sliding may be defined by controlling the rotation of the motor described above, or may be defined by providing physical objects such as stoppers at respective positions to become the start position Ps and the release position Pt.Stopper Unit

[0046] FIGS. 4A and 4B are perspective views of the stopper unit 12. The stopper unit 12 is configured to allow drawing of the strip-shaped film 10 to be stopped by clamping the strip-shaped film 10. More specifically, the stopper unit 12 includes a pressure part 121 that pressurizes the strip-shaped film 10 from above, and a stage 122 that receives the pressure force from the pressure part 121 under the strip-shaped film 10.

[0047] Still more specifically, the pressure part 121 includes a plate 121A having a lower surface arranged face-to-face with an upper surface of the stage 122, and a drive part 121B (such as an actuator) that moves the plate 121A up and down. The pressure part 121 is configured to selectively allow the lower surface of the plate 121A to move farther from the upper surface of the stage 122 (see FIG. 4A) and allow the lower surface of the plate 121A to move closer to the upper surface of the stage 122 (see FIG. 4B) in response to up and down movements of the plate 121A caused by the drive part 121B. Here, moving of the lower surface of the plate 121A closer to the upper surface of the stage 122 means a state where, in response to moving down the plate 121A with the strip-shaped film 10 placed on the stage 122, the lower surface of the plate 121A comes into surface-contact with the strip-shaped film 10 and pressurizes the strip-shaped film 10 from above. By pressurizing the strip-shaped film 10 from above using the plate 121A in this way, it becomes possible to clamp the strip-shaped film 10 between the plate 121A and the stage 122. This eventually allows drawing of the strip-shaped film 10 to be stopped.

[0048] In the present embodiment, the stopper unit 12 includes a first stopper Hp1 located at the center in the width direction Dy, and second stoppers Hp2 in a pair located on opposite sides of the first stopper Hp1 in the width direction Dy. Each of these three stoppers is composed of the pressure part 121 and the stage 122.

[0049] In the present embodiment, the stopper unit 12 is configured in such a manner that, when the stopper unit 12 clamps the strip-shaped film 10, the opposite ends Rfa and Rfb of the head region Rft protrude from the stopper unit 12 (more specifically, from the second stoppers Hp2 in a pair) to become ready to be chucked by the chuck parts Fp in a pair (see FIG. 9F).

[0050] More specifically, the stopper unit 12 is configured to allow the positions of the second stoppers Hp2 in a pair in the width direction Dy to be adjusted using a ball screw 123 in order to allow the positions of external edges of the second stoppers Hp2 in a pair (more specifically, external edges of the plate 121A and the stage 122) in the width direction Dy to be adjusted. Still more specifically, the stopper unit 12 is configured to allow the second stoppers Hp2 in a pair to move toward directions opposite to each other in the width direction Dy by rotating a handle 124 with a hand to rotate a shaft of the ball screw 123.

[0051] According to the described packaging film piece forming mechanism 1, the strip-shaped film 10 can be drawn by moving the chuck parts Fp in a pair to the release position Pt with the head region Rft of the strip-shaped film 10 chucked by the chuck parts Fp in a pair. On the other hand, the drawing of the strip-shaped film 10 can be stopped by clamping the strip-shaped film 10 using the stopper unit 12. By performing both of these, it becomes possible to generate tension on the strip-shaped film 10. By using the resultant tension, it becomes possible to tear off the head region Rft of the strip-shaped film 10 along the perforated line Pm at a boundary with the next region Rf. In this way, it is possible to form the packaging film piece Of without using a cutting blade. The motion of the packaging film piece forming mechanism 1 during formation of the packaging film piece Qf will be described later in detail.[1-2] Transport Mechanism

[0052] The transport mechanism 2 is a mechanism for transporting the packaging target 20 (such as a food container), and includes a loader 21 and an unloader 22 movable closer to and farther from each other in the transport direction Dx (see FIGS. 1A and 5). Each of the loader 21 and the unloader 22 is configured using a unit such as a conveyor that allows transport of the packaging target 20. The transport mechanism 2 is configured to allow formation of space Sw at a position under the release position Pt at which the packaging target 20 is allowed to lie astride the space Sw by moving the loader 21 and the unloader 22 farther from each other as shown in FIG. 5.

[0053] According to the described transport mechanism 2, by moving the loader 21 and the unloader 22 farther from each other to form the space Sw at a position under the release position Pt, it becomes possible to expose a bottom surface of the packaging target 20 lying astride the space Sw (see FIG. 5).[1-3] Affixing Mechanism

[0054] The affixing mechanism 3 is a mechanism for affixing the packaging film piece Of formed by the packaging film piece forming mechanism 1 to the packaging target 20 being transported by the transport mechanism 2. The affixing mechanism 3 includes a first press unit 31 and a second press unit 32 (see FIGS. 1A and 5).

[0055] FIG. 6 is a conceptual view showing the first press unit 31 and the second press unit 32 viewed from the transport direction Dx. FIG. 7A is a conceptual view showing the motion of the first press unit 31. FIGS. 7B and 7C are conceptual views showing a first phase and a second phase of the motion of the second press unit 32 respectively.

[0056] The first press unit 31 is configured to allow the packaging film piece Qf to be pressed against an upper surface of the packaging target 20 after the packaging film piece Of is released from chucking by the chuck parts Fp in a pair at the release position Pt (see FIG. 7A).

[0057] More specifically, the first press unit 31 includes a press arm 311, and a drive part 312 (such as an actuator) that moves the press arm 311 up and down (see FIGS. 1A, 6, and 7A). The press arm 311 is arranged in such a manner as to allow a central portion of the packaging film piece Of to be pressed against the upper surface of the packaging target 20 when the press arm 311 is moved down by the drive part 312 (see FIG. 7A). By pressing the packaging film piece Of against the upper surface of the packaging target 20 using the first press unit 31, the packaging film piece Of is put into a state where opposite ends Qfa and Qfb thereof are suspended downward (see FIG. 7A).

[0058] The second press unit 32 is configured to allow the opposite ends Qfa and Qfb of the packaging film piece Qf suspended downward to be pressed against the bottom surface of the packaging target 20 (see FIGS. 7B and 7C).

[0059] More specifically, the second press unit 32 includes press rolls 321 in a pair and a drive part 322 (such as an actuator) that moves the press rolls 321 in a pair to a position corresponding to the bottom surface of the packaging target 20 (see FIGS. 1A, 6, 7A, and 7B). In the present embodiment, the second press unit 32 is configured to allow the opposite ends Qfa and Qfb of the packaging film piece Qf to be pressed reliably against the bottom surface of the packaging target 20 while reducing impact on the packaging target 20 by moving the press rolls 321 in a pair along arc-like curves to the bottom surface of the packaging target 20 (see FIGS. 7B and 7C). The second press unit 32 is also configured to allow the press rolls 321 in a pair to move to the bottom surface of the packaging target 20 at timing differing between the press rolls 321. More specifically, the second press unit 32 can make the motion of moving one of the press rolls 321 first to press the end Qfa of the packaging film piece Of against the bottom surface of the packaging target 20 (see FIG. 7B), and then moving the other press roll 321 to press the end Qfb of the packaging film piece Qf against the bottom surface of the packaging target 20 (see FIG. 7C).

[0060] The second press unit 32 is not limited to a unit that moves the press rolls 321 in a pair along the arc-like curves but may be changed, as appropriate, to a unit that moves the press rolls 321 in a pair horizontally to the bottom surface of the packaging target 20. The press roll 321 may have a roll surface made of a cushioning material in order to allow relaxation of impact occurring during pressing of the packaging film piece Of against the bottom surface of the packaging target 20.

[0061] According to the described affixing mechanism 3,

[0062] while the central portion of the packaging film piece Qf is placed on the upper surface of the packaging target 20 by the first press unit 31, it is possible to guide smoothly the opposite ends Qfa and Qfb of the packaging film piece Of to the bottom surface of the packaging target 20 by the second press unit 32. This makes it possible to affix the opposite ends Qfa and Qfb at the bottom surface of the packaging target 20.[1-4] Controller

[0063] The controller 4 includes a storage unit 41 and a control unit 42 (see FIG. 1B). The storage unit 41 is a unit in which information necessary for control over the packaging apparatus (such as parameters necessary for control over the packaging film piece forming mechanism 1, the transport mechanism 2, and the affixing mechanism 3, etc.) is stored, and is configured using a storage device such as a ROM or a RAM. The control unit 42 is a unit that implements the control over the packaging apparatus, and is configured using a processing device such as a CPU. The following describes control processing in detail performed by the controller 4 in the packaging apparatus.

[0064] FIG. 8 is a flowchart showing the control processing performed by the controller 4. FIGS. 9A to 9F are perspective views showing the motion of the packaging film piece forming mechanism 1 in order resulting from the control processing.

[0065] First, the controller 4 controls the chuck unit 11 to move the chuck parts Fp in a pair to the start position Ps, and causes the chuck parts Fp in a pair to chuck the head region Rft of the strip-shaped film 10 (step S101, see FIG. 9A). At this time, the controller 4 controls the stopper unit 12 to cause the stopper unit 12 to keep a state of clamping the head region Rft of the strip-shaped film 10. More specifically, the controller 4 causes the stopper unit 12 to keep a state where the pressure part 121 is at a moved-down position, thereby keeping a state where the head region Rft of the strip-shaped film 10 is pressurized by the pressure part 121. By doing so, it becomes possible to reliably prevent a curl likely to occur at the head region Rft of the strip-shaped film 10.

[0066] After step S101, the controller 4 controls the stopper unit 12 to cause the stopper unit 12 to release the head region Rft of the strip-shaped film 10 from the clamping (step S102, see FIG. 9B). More specifically, the controller 4 moves up the pressure part 121 to release the head region Rft of the strip-shaped film 10 from the pressurizing by the pressure part 121. By doing so, the strip-shaped film 10 is released from the halting by the stopper unit 12. As a result, the strip-shaped film 10 becomes ready to be drawn in the transport direction Dx.

[0067] After step S102, the controller 4 controls the chuck unit 11 to cause the chuck parts Fp in a pair to start moving from the start position Ps toward the release position Pt while causing the chuck parts Fp in a pair to continue chucking of the head region Rft (step S103). By doing so, the strip-shaped film 10 is pulled by the chuck parts Fp in a pair to be drawn in the transport direction Dx (see FIG. 9C).

[0068] After step S103, the controller 4 controls the chuck unit 11 to stop the chuck parts Fp in a pair temporarily on the way of moving chuck parts Fp in a pair toward the release position Pt (step S104, see FIG. 9C). More specifically, the controller 4 stops the chuck parts Fp in a pair temporarily when the perforated line Pm at a boundary between the head region Rft chucked by the chuck parts Fp in a pair and the next region Rf entirely goes out of a clamping range Rx where clamping is to be done by the stopper unit 12.

[0069] After step S104, the controller 4 controls the stopper unit 12 to cause the stopper unit 12 to clamp the next region Rf connected to the head region Rft across the perforated line Pm (step S105, see FIG. 9D). More specifically, the controller 4 moves down the pressure part 121 to pressurize this next region with the pressure part 121. By doing so, drawing of the strip-shaped film 10 in the transport direction Dx is halted by the stopper unit 12.

[0070] After step S105, the controller 4 controls the chuck unit 11 to restart moving of the chuck parts Fp in a pair toward the release position Pt, thereby tearing off the head region Rft of the strip-shaped film 10 along the perforated line Pm at the boundary with the next region Rf using instantaneous force generated at the time of the restart (step S106, see FIG. 9E).

[0071] As a result of steps S105 and S106, while drawing of the strip-shaped film 10 is stopped by clamping the next region Rf continuous with the head region Rft, it is possible to pull the head region Rft with the chuck parts Fp in a pair. As a result, using tension generated on the strip-shaped film 10 by the pulling, only the head region Rft can be torn off along the perforated line Pm at the boundary with the next region Rf. The torn-off head region Rft becomes one packaging film piece Qf. Furthermore, restarting moving of the chuck parts Fp in a pair generates instantaneous force, and the strip-shaped film 10 is broken easily along the perforated line Pm by using the generated instantaneous force.

[0072] After step S106, the controller 4 controls the chuck unit 11 to cause the chuck parts Fp in a pair to release chucking of the packaging film piece Qf when the chuck parts Fp in a pair reach the release position Pt (step S107, see FIG. 9F). By doing so, the packaging film piece Of is released from chucking by the chuck parts Fp in a pair.

[0073] The controller 4 controls the transport mechanism 2 to start loading of the packaging target 20 (step S201), and causes the transport mechanism 2 to transport the packaging target 20 to a position under the release position Pt and then stop the packaging target 20 (step S202), by the time implementation of step S107 is completed. At this time, the controller 4 moves the loader 21 and the unloader 22 farther from each other to form the space Sw, and stops the packaging target 20 while causing the packaging target 20 to lie astride the space Sw (see FIG. 5). By doing so, the packaging target 20 is placed in a state ready to be packaged with the packaging film piece Qf by the affixing mechanism 3 (a state where the bottom surface of the packaging target 20 is exposed).

[0074] After steps S107 and S202, the controller 4 controls the affixing mechanism 3 to cause the first press unit 31 to press the central portion of the packaging film piece Of against the upper surface of the packaging target 20 (step S301, see FIG. 7A). By doing so, the packaging film piece Of is put into a state where the opposite ends Qfa and Qfb thereof are suspended downward.

[0075] After step S301, the controller 4 controls the affixing mechanism 3 to cause the second press unit 32 to press the opposite ends Qfa and Qfb of the packaging film piece Qf against the bottom surface of the packaging target 20 (step S302, see FIGS. 7B and 7C). By doing so, affixation of the opposite ends Qfa and Qfb is done at the bottom surface of the packaging target 20. As a result, affixation of the packaging film piece Qf to the packaging target 20 (packaging of the packaging target 20 with the packaging film piece Qf) is completed.

[0076] After step S302, the controller 4 controls the transport mechanism 2 to move the loader 21 and the unloader 22 closer to each other, thereby placing the packaging target 20 already packaged on the unloader 22 and unloading the packaging target 20 (step S203).

[0077] The controller 4 thereafter returns to step S101 and step S201 and performs the processing from step S101 and the processing from step S201 repeatedly. In this way, in the packaging apparatus, it is possible to form the packaging film piece Qf and affix the packaging film piece Of to the packaging target 20 (package the packaging target 20 with the packaging film piece Qf) repeatedly and continuously.

[0078] As described above, the packaging film piece forming mechanism 1 according to the present embodiment can form the packaging film piece Qf without using a cutting blade. Thus, it is possible to improve maintenance performance in the packaging film piece forming mechanism 1 and the packaging apparatus. In this way, both improvement of maintenance performance and implementation of continuous operation are achieved in the above-described packaging film piece forming mechanism 1 and packaging apparatus.

[0079] Furthermore, in the present embodiment, when the above-described control processing is repeated, the controller 4 causes the stopper unit 12 to clamp the next region Rf continuous with the head region Rft of the strip-shaped film 10 in step S105, and thereafter causes the stopper unit 12 to continue this state until the processing returns to step S101 to start chucking of this next region Rf (in other words, a new head region Rft generated as a result of tearing-off of the head region Rft).

[0080] According to the described control processing, after the next region Rf becomes the new head region Rft as a result of tearing-off of the head region Rft, the next region Rf is kept clamped by the stopper unit 12 until it is chucked by the chuck parts Fp in a pair. This makes it possible to reliably prevent a curl likely to occur at the head region Rft of the strip-shaped film 10.

[0081] According to the above-described packaging apparatus, it is possible to appropriately adjust a degree of drawing of the strip-shaped film10 by the chuck parts Fp in a pair or the size of the space Sw to be formed between the loader 21 and the unloader 22 (a degree of separation between the loader 21 and the unloader 22) in response to the length of the packaging film piece Qf to be formed (a length between the perforated lines Pm next to each other). Thus, the packaging apparatus according to the present embodiment provides a high degree of freedom in terms of the size or shape of the applicable packaging film piece Qf and further in terms of the size or shape of the packaging target 20.

[0082] The above explanations of the embodiments are nothing more than illustrative in any respect, nor should be thought of as restrictive. The scope of the present invention is indicated by claims rather than the above embodiments. Furthermore, it is intended that all changes that are equivalent to a claim in the sense and realm of the doctrine of equivalence be included within the scope of the present invention.REFERENCE SIGNS LIST1 Packaging film piece forming mechanism

[0084] 2 Transport mechanism

[0085] 3 Affixing mechanism

[0086] 4 Controller

[0087] 10 Strip-shaped film

[0088] 11 Chuck unit

[0089] 12 Stopper unit

[0090] 20 Packaging target

[0091] 21 Loader

[0092] 22 Unloader

[0093] 31 First press unit

[0094] 32 Second press unit

[0095] 41 Storage unit

[0096] 42 Control unit

[0097] Dx Transport direction

[0098] Dy Width direction

[0099] Fp Chuck part

[0100] Gp Sliding transport part

[0101] Hp1 First stopper

[0102] Hp2 Second stopper

[0103] Pm Perforated line

[0104] Ps Start position

[0105] Pt Release position

[0106] Qf Packaging film piece

[0107] Qfa, Qfb End

[0108] Rf Region

[0109] Rft Head region

[0110] Rfa, Rfb End

[0111] Rx Clamping range

[0112] Sw Space

[0113] 111 Upper chuck structure

[0114] 112 Lower chuck structure

[0115] 113 Support

[0116] 113A Beam

[0117] 113B Support arm

[0118] 113C Ball screw

[0119] 113D Handle

[0120] 114 Guide

[0121] 121 Pressure part

[0122] 121A Plate

[0123] 121B Drive part

[0124] 122 Stage

[0125] 123 Ball screw

[0126] 124 Handle

[0127] 311 Press arm

[0128] 312 Drive part

[0129] 321 Press roll

[0130] 322 Drive part

Examples

Embodiment Construction

[1] Configuration of Packaging Apparatus

[0032]FIGS. 1A and 1B are a front view and a block diagram respectively conceptually showing a packaging apparatus according to an embodiment. As shown in these drawings, the packaging apparatus includes a packaging film piece forming mechanism 1, a transport mechanism 2, an affixing mechanism 3, and a controller 4. The configurations of these units will be described below in detail.

[1-1] Packaging Film Piece Forming Mechanism

[0033]FIG. 2A is a perspective view conceptually showing a strip-shaped film 10 used in the packaging film piece forming mechanism 1 according to the present embodiment. As shown in this drawing, the strip-shaped film 10 is an elongated film with a plurality of regions Rf connected to each other continuously across perforated lines Pm. Here, each region Rf is a region to become a film piece (packaging film piece Qf) used for packaging of a packaging target 20 (such as a food container, see FIG. 5). The strip-shaped film 1...

TECHNICAL FIELD

[0001] The present invention relates to a technique for forming a packaging film piece from a continuous strip-shaped film, and a packaging technique using the packaging film piece.BACKGROUND ART

[0002] The technique for forming a packaging film piece from a continuous strip-shaped film includes a generally-known technique by which the strip-shaped film is cut at a predetermined position using a cutting blade. As an example, Patent Literature 1 disclosures a technique by which a strip-shaped film is drawn by a predetermined length by grasping opposite sides of the film with an arm and thereafter a cutting blade is moved down, thereby cutting the strip-shaped film at a predetermined position and forming a packaging film piece having the predetermined length.CITATION LISTPatent Literature

[0003] Patent Literature 1: Japanese published unexamined patent No. 2021-116081SUMMARY OF INVENTIONTechnical Problem

[0004] According to the conventional technique using the cutting blade, however, maintenance (such as changing) of the cutting blade is required to be done regularly. Furthermore, in order to cut the strip-shaped film at the predetermined position, the predetermined position and a position to which the cutting blade is to be moved down are required to be aligned with each other correctly. To achieve this, a high-precision mechanism or high-precision control is required.

[0005] Furthermore, for cutting the strip-shaped film with the cutting blade, the strip-shaped film is required to be applied with tension to become free from a slack. In response to this, according to the technique disclosed in Patent Literature 1, tension is applied to the strip-shaped film using a roller that unwinds the strip-shaped film and the arm that draws the strip-shaped film. If the strip-shaped film is cut in this state, however, the strip-shaped film might be curled in a part having become a new head as a result of the cutting when the tension is lost by the cutting. The occurrence of such a curl makes it hard to grasp the strip-shaped film with the arm in preparation for next cutting, and this causes hindrance to continuous operation of a packaging apparatus.

[0006] Thus, in relation to a technique of forming a packaging film piece, the present invention is intended to achieve both improvement of maintenance performance and implementation of continuous operation.Solution to Problem

[0007] A packaging film piece forming mechanism according to the present invention is a mechanism that allows formation of a plurality of packaging film pieces sequentially using a strip-shaped film including a plurality of regions to become the packaging film pieces and to be connected continuously to each other across a perforated line, in such a manner as to form each of the packaging film pieces from a head region at a head of the strip-shaped film among the regions. The packaging film piece forming mechanism comprises a chuck unit and a stopper unit. The chuck unit is a unit that includes chuck parts in a pair that chuck corresponding opposite ends of the head region in a width direction, and allows the chuck parts in a pair to move back and forth between a start position at which chucking of the head region is started and a release position separated from the start position toward a direction in which the strip-shaped film is drawable and at which the head region is released from chucking. The stopper unit is a unit that allows drawing of the strip-shaped film to be stopped by clamping the strip-shaped film.

[0008] According to the above-described packaging film piece forming mechanism, the strip-shaped film can be drawn by moving the chuck parts in a pair to the release position with the head region of the strip-shaped film chucked by the chuck parts in a pair. On the other hand, the drawing of the strip-shaped film can be halted by clamping the strip-shaped film using the stopper unit. By performing both of these, it becomes possible to generate tension on the strip-shaped film. By using the resultant tension, it becomes possible to tear off the head region of the strip-shaped film along the perforated line at a boundary with a next region. In this way, it is possible to form the packaging film piece without using a cutting blade.

[0009] In the above-described packaging film piece forming mechanism, the stopper unit may be configured in such a manner that, when the stopper unit clamps the strip-shaped film, the opposite ends of the head region in the width direction protrude from the stopper unit to become ready to be chucked by the chuck parts in a pair.

[0010] A packaging apparatus according to the present invention comprises: the above-described packaging film piece forming mechanism; and a controller. The controller causes the chuck parts in a pair to chuck the head region of the strip-shaped film at the start position. Next, the controller causes the chuck parts in a pair to continue chucking of the head region and moves the chuck parts in a pair from the start position toward the release position. On the way of moving the chuck parts in a pair toward the release position, the controller causes the stopper unit to clamp a next region connected to the head region across the perforated line.

[0011] According to the above-described packaging apparatus, while drawing of the strip-shaped film is stopped by clamping the next region continuous with the head region, it is possible to pull the head region with the chuck parts in a pair. As a result, using tension generated on the strip-shaped film by the pulling, only the head region can be torn off along the perforated line at the boundary with the next region. The torn-off region becomes one packaging film piece.

[0012] In the above-described packaging apparatus, the controller may perform control as follows. On the way of moving the chuck parts in a pair toward the release position, the controller stops the chuck parts in a pair temporarily when the perforated line at a boundary between the head region chucked by the chuck parts in a pair and the next region entirely goes out of a clamping range where clamping is to be done by the stopper unit and then causes the stopper unit to clamp the next region. The controller thereafter restarts moving of the chuck parts in a pair, thereby tearing off the head region of the strip-shaped film along the perforated line at the boundary with the next region using instantaneous force generated at the time of the restart. According to this configuration, the strip-shaped film is broken easily along the perforated line by using the generated instantaneous force.

[0013] In the above-described packaging apparatus, the controller may perform control as follows. After causing the stopper unit to clamp the next region continuous with the head region chucked by the chuck parts in a pair on the way of moving the chuck parts in a pair toward the release position, the controller causes the stopper unit to continue a state of the clamping until chucking of the next region by the chuck parts in a pair is started. According to this configuration, after the next region becomes a new head region as a result of tearing-off of the head region, the next region is kept clamped by the stopper unit until it is chucked by the chuck parts in a pair. This makes it possible to reliably prevent a curl likely to occur at the head region of the strip-shaped film.

[0014] The packaging apparatus may further comprise a transport mechanism that transports a packaging target, and an affixing mechanism. The affixing mechanism is a mechanism that affixes the packaging film piece formed by the packaging film piece forming mechanism to the packaging target being transported by the transport mechanism.

[0015] More specifically, the transport mechanism may include a loader and an unloader movable closer to and farther from each other in a transport direction, and may be configured to allow formation of space at a position under the release position at which the packaging target is allowed to lie astride the space by moving the loader and the unloader farther from each other. The affixing mechanism may include a first press unit and a second press unit. The first press unit is a unit that allows the packaging film piece to be pressed against an upper surface of the packaging target to put the packaging film piece into a state where opposite ends thereof are suspended downward after the packaging film piece is released from chucking by the chuck parts in a pair at the release position. The second press unit is a unit that allows the opposite ends of the packaging film piece suspended downward to be pressed against a bottom surface of the packaging target.

[0016] According to this configuration, by moving the loader and the unloader farther from each other to form the space at a position under the release position, it becomes possible to expose the bottom surface of the packaging target lying astride the space. Moreover, while a central portion of the packaging film piece is placed on the upper surface of the packaging target by the first press unit, it is possible to guide smoothly the opposite ends of the packaging film piece to the bottom surface of the packaging target by the second press unit. This makes it possible to affix the opposite ends at the bottom surface of the packaging target.Advantageous Effects of Invention

[0017] According to the present invention, in relation to a technique of forming a packaging film piece, it is possible to achieve both improvement of maintenance performance and implementation of continuous operation.BRIEF DESCRIPTION OF DRAWINGS

[0018] FIG. 1A is a front view conceptually showing a packaging apparatus according to an embodiment, and FIG. 1B is a block diagram conceptually showing the packaging apparatus.

[0019] FIG. 2A is a perspective view conceptually showing a strip-shaped film used in a packaging film piece forming mechanism of a packaging apparatus, and FIG. 2B is a perspective view conceptually showing the packaging film piece forming mechanism.

[0020] FIGS. 3A and 3B are perspective views of a chuck unit of the packaging film piece forming mechanism. FIG. 3A shows a case where a chuck part is closed, and FIG. 3B shows a case where the chuck part is opened.

[0021] FIGS. 4A and 4B are perspective views of a stopper unit of the packaging film piece forming mechanism. FIG. 4A shows a case where a plate is separated from a stage, and FIG. 4B shows a case where the plate is adjacent to the stage.

[0022] FIG. 5 is a front view of the packaging apparatus showing a case where a loader and an unloader of a transport mechanism of the packaging apparatus are separated from each other.

[0023] FIG. 6 is a conceptual view showing a first press unit and a second press unit of an affixing mechanism of the packaging apparatus viewed from a transport direction.

[0024] FIG. 7A is a conceptual view showing the motion of the first press unit, FIG. 7B is a conceptual view showing a first phase of the motion of the second press unit, and FIG. 7C is a conceptual view showing a second phase of the motion of the second press unit.

[0025] FIG. 8 is a flowchart showing control processing performed by a controller of the packaging apparatus.

[0026] FIG. 9A is a perspective view showing the motion of the packaging film piece forming mechanism in order.

[0027] FIG. 9B is a perspective view showing the motion of the packaging film piece forming mechanism in order.

[0028] FIG. 9C is a perspective view showing the motion of the packaging film piece forming mechanism in order.

[0029] FIG. 9D is a perspective view showing the motion of the packaging film piece forming mechanism in order.

[0030] FIG. 9E is a perspective view showing the motion of the packaging film piece forming mechanism in order.

[0031] FIG. 9F is a perspective view showing the motion of the packaging film piece forming mechanism in order.DESCRIPTION OF EMBODIMENTS[1] Configuration of Packaging Apparatus

[0032] FIGS. 1A and 1B are a front view and a block diagram respectively conceptually showing a packaging apparatus according to an embodiment. As shown in these drawings, the packaging apparatus includes a packaging film piece forming mechanism 1, a transport mechanism 2, an affixing mechanism 3, and a controller 4. The configurations of these units will be described below in detail.[1-1] Packaging Film Piece Forming Mechanism

[0033] FIG. 2A is a perspective view conceptually showing a strip-shaped film 10 used in the packaging film piece forming mechanism 1 according to the present embodiment. As shown in this drawing, the strip-shaped film 10 is an elongated film with a plurality of regions Rf connected to each other continuously across perforated lines Pm. Here, each region Rf is a region to become a film piece (packaging film piece Qf) used for packaging of a packaging target 20 (such as a food container, see FIG. 5). The strip-shaped film 10 is coated with an adhesive applied in advance for allowing the packaging film piece Qf to be affixed to the packaging target 20. The adhesive is applied to a predetermined width along each of opposite edges of the packaging target 20, for example.

[0034] FIG. 2B is a perspective view conceptually showing the packaging film piece forming mechanism 1. The packaging film piece forming mechanism 1 is a mechanism for allowing formation of a plurality of the packaging film pieces Qf sequentially using the above-described strip-shaped film 10, in such a manner as to from each of the packaging film pieces Qf from a head region Rft at a head of the strip-shaped film 10 among the regions Rf (see FIG. 2A). The packaging film piece forming mechanism 1 includes a chuck unit 11 and a stopper unit 12.

[0035] The strip-shaped film 10 is in a roll shape by being wound around a core, for example (see FIG. 2A), and is drawn only by drawing force from the chuck unit 11 described below. In other words, the packaging apparatus according to the present embodiment does not always require a motor for unwinding the strip-shaped film 10. At the packaging apparatus according to the present embodiment, the strip-shaped film 10 is arranged in a manner allowing the strip-shaped film 10 to be drawn in the same direction as a transport direction Dx in which the packaging target 20 is transported by the transport mechanism 2 described later. The packaging apparatus is not limited to this but may be changed, as appropriate, to an apparatus with a motor for unwinding the strip-shaped film 10 secondarily in response to drawing of the strip-shaped film 10.Chuck Unit

[0036] FIGS. 3A and 3B are perspective views of the chuck unit 11. The chuck unit 11 includes chuck parts Fp in a pair and a sliding transport part Gp.

[0037] The chuck parts Fp in a pair are configured to allow chucking of corresponding opposite ends Rfa and Rfb (opposite ends in a width direction Dy, see FIG. 2A) of the head region Rft of the strip-shaped film 10 (see FIG. 9A). More specifically, each chuck part Fp includes an upper chuck structure 111 and a lower chuck structure 112, and is configured to be openable and closable by moving the upper chuck structure 111 and the lower chuck structure 112 vertically toward directions opposite to each other. In the drawings, FIG. 3A shows a case where the chuck part FP is closed, and FIG. 3B shows a case where the chuck part Fp is opened.

[0038] Still more specifically, at each chuck part Fp, the upper chuck structure 111 is composed of an L-shape block with a tip projecting downward and the lower chuck structure 112 is composed of an L-shape block with a tip projecting upward. These blocks are configured in such a manner that respective tip surfaces (planes) thereof come into surface-contact with each other when the blocks are closed. The described chuck part Fp can chuck a corresponding one of the opposite ends Rfa and Rfb of the head region Rft by clamping a part of the corresponding opposite end Rfa or Rfb not applied with the adhesive. If the adhesive is applied to a predetermined width along each of the opposite edges of the strip-shaped film 10, for example, a part of each of the opposite ends Rfa and Rfb internal to the predetermined width can be clamped with the L-shape tips.

[0039] Each chuck part Fp is configured in such a manner that, even when the chuck part Fp is intended to pull the strip-shaped film 10 by moving of the chuck part Fp described below after the chuck part Fp clamps the strip-shaped film 10 using the upper chuck structure 111 and the lower chuck structure 112, the chuck part Fp can keep a state of grasping the strip-shaped film 10, in other words, can prevent the strip-shaped film 10 from slipping and coming off. Still more specifically, force of clamping the strip-shaped film 10, frictional force at the tip surface, etc. are adjusted appropriately.

[0040] The sliding transport part Gp is configured to allow the chuck parts Fp in a pair to move back and forth between a start position Ps (see FIGS. 1 and 9A) at which chucking of the head region Rft of the strip-shaped film 10 is started and a release position Pt (see FIGS. 5 and 9F) separated from the start position Ps toward a direction (same as the transport direction Dx in the present embodiment) in which the strip-shaped film 10 is drawable and at which the head region Rft is released from chucking.

[0041] More specifically, the sliding transport part Gp includes a support 113 supporting the chuck parts Fp in a pair, and a guide 114 that moves the chuck parts Fp in a pair back and forth by causing the support 113 to slide. In the present embodiment, the guide 114 defines a direction in which it causes the support 113 to slide to be the same as the transport direction Dx.

[0042] Still more specifically, the support 113 is composed of a beam 113A extending in the width direction Dy and slidably mounted on the guide 114, and support arms 113B in a pair supporting the chuck parts Fp in a pair at predetermined height positions. The predetermined height positions mentioned herein are height positions at which the strip-shaped film 10 is allowed to pass through between the upper chuck structure 111 and the lower chuck structure 112 when the support 113 is caused to slide along the guide 114 with the chuck part Fp in an opened state.

[0043] In the present embodiment, the support 113 is configured to allow adjustment of a distance between the chuck parts Fp in a pair. More specifically, the support 113 is configured to allow the positions of the support arms 113B in a pair in the width direction Dy to be adjusted using a ball screw 113C. Still more specifically, the support 113 is configured to allow the support arms 113B in a pair to move toward directions opposite to each other in the width direction Dy by rotating a handle 113D with a hand to rotate a shaft of the ball screw 113C.

[0044] The guide 114 has a built-in ball screw (not shown in the drawings), and causes the support 113 to slide by rotating a shaft of this ball screw using a motor (not shown in the drawings). With this configuration of the guide 114, controlling a direction of rotation of the motor (forward direction and reverse direction) allows the support 113 to move back and forth in an axis direction of the ball screw. In the present embodiment, the guide 114 is arranged in such a manner that the axis direction of this ball screw becomes the same as the transport direction Dx.

[0045] Furthermore, in the present embodiment, a range of sliding of the support 113 is defined in such a manner as to allow the chuck parts Fp in a pair to move back and forth between the start position Ps and the release position Pt described above. This range of sliding may be defined by controlling the rotation of the motor described above, or may be defined by providing physical objects such as stoppers at respective positions to become the start position Ps and the release position Pt.Stopper Unit

[0046] FIGS. 4A and 4B are perspective views of the stopper unit 12. The stopper unit 12 is configured to allow drawing of the strip-shaped film 10 to be stopped by clamping the strip-shaped film 10. More specifically, the stopper unit 12 includes a pressure part 121 that pressurizes the strip-shaped film 10 from above, and a stage 122 that receives the pressure force from the pressure part 121 under the strip-shaped film 10.

[0047] Still more specifically, the pressure part 121 includes a plate 121A having a lower surface arranged face-to-face with an upper surface of the stage 122, and a drive part 121B (such as an actuator) that moves the plate 121A up and down. The pressure part 121 is configured to selectively allow the lower surface of the plate 121A to move farther from the upper surface of the stage 122 (see FIG. 4A) and allow the lower surface of the plate 121A to move closer to the upper surface of the stage 122 (see FIG. 4B) in response to up and down movements of the plate 121A caused by the drive part 121B. Here, moving of the lower surface of the plate 121A closer to the upper surface of the stage 122 means a state where, in response to moving down the plate 121A with the strip-shaped film 10 placed on the stage 122, the lower surface of the plate 121A comes into surface-contact with the strip-shaped film 10 and pressurizes the strip-shaped film 10 from above. By pressurizing the strip-shaped film 10 from above using the plate 121A in this way, it becomes possible to clamp the strip-shaped film 10 between the plate 121A and the stage 122. This eventually allows drawing of the strip-shaped film 10 to be stopped.

[0048] In the present embodiment, the stopper unit 12 includes a first stopper Hp1 located at the center in the width direction Dy, and second stoppers Hp2 in a pair located on opposite sides of the first stopper Hp1 in the width direction Dy. Each of these three stoppers is composed of the pressure part 121 and the stage 122.

[0049] In the present embodiment, the stopper unit 12 is configured in such a manner that, when the stopper unit 12 clamps the strip-shaped film 10, the opposite ends Rfa and Rfb of the head region Rft protrude from the stopper unit 12 (more specifically, from the second stoppers Hp2 in a pair) to become ready to be chucked by the chuck parts Fp in a pair (see FIG. 9F).

[0050] More specifically, the stopper unit 12 is configured to allow the positions of the second stoppers Hp2 in a pair in the width direction Dy to be adjusted using a ball screw 123 in order to allow the positions of external edges of the second stoppers Hp2 in a pair (more specifically, external edges of the plate 121A and the stage 122) in the width direction Dy to be adjusted. Still more specifically, the stopper unit 12 is configured to allow the second stoppers Hp2 in a pair to move toward directions opposite to each other in the width direction Dy by rotating a handle 124 with a hand to rotate a shaft of the ball screw 123.

[0051] According to the described packaging film piece forming mechanism 1, the strip-shaped film 10 can be drawn by moving the chuck parts Fp in a pair to the release position Pt with the head region Rft of the strip-shaped film 10 chucked by the chuck parts Fp in a pair. On the other hand, the drawing of the strip-shaped film 10 can be stopped by clamping the strip-shaped film 10 using the stopper unit 12. By performing both of these, it becomes possible to generate tension on the strip-shaped film 10. By using the resultant tension, it becomes possible to tear off the head region Rft of the strip-shaped film 10 along the perforated line Pm at a boundary with the next region Rf. In this way, it is possible to form the packaging film piece Of without using a cutting blade. The motion of the packaging film piece forming mechanism 1 during formation of the packaging film piece Qf will be described later in detail.[1-2] Transport Mechanism

[0052] The transport mechanism 2 is a mechanism for transporting the packaging target 20 (such as a food container), and includes a loader 21 and an unloader 22 movable closer to and farther from each other in the transport direction Dx (see FIGS. 1A and 5). Each of the loader 21 and the unloader 22 is configured using a unit such as a conveyor that allows transport of the packaging target 20. The transport mechanism 2 is configured to allow formation of space Sw at a position under the release position Pt at which the packaging target 20 is allowed to lie astride the space Sw by moving the loader 21 and the unloader 22 farther from each other as shown in FIG. 5.

[0053] According to the described transport mechanism 2, by moving the loader 21 and the unloader 22 farther from each other to form the space Sw at a position under the release position Pt, it becomes possible to expose a bottom surface of the packaging target 20 lying astride the space Sw (see FIG. 5).[1-3] Affixing Mechanism

[0054] The affixing mechanism 3 is a mechanism for affixing the packaging film piece Of formed by the packaging film piece forming mechanism 1 to the packaging target 20 being transported by the transport mechanism 2. The affixing mechanism 3 includes a first press unit 31 and a second press unit 32 (see FIGS. 1A and 5).

[0055] FIG. 6 is a conceptual view showing the first press unit 31 and the second press unit 32 viewed from the transport direction Dx. FIG. 7A is a conceptual view showing the motion of the first press unit 31. FIGS. 7B and 7C are conceptual views showing a first phase and a second phase of the motion of the second press unit 32 respectively.

[0056] The first press unit 31 is configured to allow the packaging film piece Qf to be pressed against an upper surface of the packaging target 20 after the packaging film piece Of is released from chucking by the chuck parts Fp in a pair at the release position Pt (see FIG. 7A).

[0057] More specifically, the first press unit 31 includes a press arm 311, and a drive part 312 (such as an actuator) that moves the press arm 311 up and down (see FIGS. 1A, 6, and 7A). The press arm 311 is arranged in such a manner as to allow a central portion of the packaging film piece Of to be pressed against the upper surface of the packaging target 20 when the press arm 311 is moved down by the drive part 312 (see FIG. 7A). By pressing the packaging film piece Of against the upper surface of the packaging target 20 using the first press unit 31, the packaging film piece Of is put into a state where opposite ends Qfa and Qfb thereof are suspended downward (see FIG. 7A).

[0058] The second press unit 32 is configured to allow the opposite ends Qfa and Qfb of the packaging film piece Qf suspended downward to be pressed against the bottom surface of the packaging target 20 (see FIGS. 7B and 7C).

[0059] More specifically, the second press unit 32 includes press rolls 321 in a pair and a drive part 322 (such as an actuator) that moves the press rolls 321 in a pair to a position corresponding to the bottom surface of the packaging target 20 (see FIGS. 1A, 6, 7A, and 7B). In the present embodiment, the second press unit 32 is configured to allow the opposite ends Qfa and Qfb of the packaging film piece Qf to be pressed reliably against the bottom surface of the packaging target 20 while reducing impact on the packaging target 20 by moving the press rolls 321 in a pair along arc-like curves to the bottom surface of the packaging target 20 (see FIGS. 7B and 7C). The second press unit 32 is also configured to allow the press rolls 321 in a pair to move to the bottom surface of the packaging target 20 at timing differing between the press rolls 321. More specifically, the second press unit 32 can make the motion of moving one of the press rolls 321 first to press the end Qfa of the packaging film piece Of against the bottom surface of the packaging target 20 (see FIG. 7B), and then moving the other press roll 321 to press the end Qfb of the packaging film piece Qf against the bottom surface of the packaging target 20 (see FIG. 7C).

[0060] The second press unit 32 is not limited to a unit that moves the press rolls 321 in a pair along the arc-like curves but may be changed, as appropriate, to a unit that moves the press rolls 321 in a pair horizontally to the bottom surface of the packaging target 20. The press roll 321 may have a roll surface made of a cushioning material in order to allow relaxation of impact occurring during pressing of the packaging film piece Of against the bottom surface of the packaging target 20.

[0061] According to the described affixing mechanism 3,

[0062] while the central portion of the packaging film piece Qf is placed on the upper surface of the packaging target 20 by the first press unit 31, it is possible to guide smoothly the opposite ends Qfa and Qfb of the packaging film piece Of to the bottom surface of the packaging target 20 by the second press unit 32. This makes it possible to affix the opposite ends Qfa and Qfb at the bottom surface of the packaging target 20.[1-4] Controller

[0063] The controller 4 includes a storage unit 41 and a control unit 42 (see FIG. 1B). The storage unit 41 is a unit in which information necessary for control over the packaging apparatus (such as parameters necessary for control over the packaging film piece forming mechanism 1, the transport mechanism 2, and the affixing mechanism 3, etc.) is stored, and is configured using a storage device such as a ROM or a RAM. The control unit 42 is a unit that implements the control over the packaging apparatus, and is configured using a processing device such as a CPU. The following describes control processing in detail performed by the controller 4 in the packaging apparatus.

[0064] FIG. 8 is a flowchart showing the control processing performed by the controller 4. FIGS. 9A to 9F are perspective views showing the motion of the packaging film piece forming mechanism 1 in order resulting from the control processing.

[0065] First, the controller 4 controls the chuck unit 11 to move the chuck parts Fp in a pair to the start position Ps, and causes the chuck parts Fp in a pair to chuck the head region Rft of the strip-shaped film 10 (step S101, see FIG. 9A). At this time, the controller 4 controls the stopper unit 12 to cause the stopper unit 12 to keep a state of clamping the head region Rft of the strip-shaped film 10. More specifically, the controller 4 causes the stopper unit 12 to keep a state where the pressure part 121 is at a moved-down position, thereby keeping a state where the head region Rft of the strip-shaped film 10 is pressurized by the pressure part 121. By doing so, it becomes possible to reliably prevent a curl likely to occur at the head region Rft of the strip-shaped film 10.

[0066] After step S101, the controller 4 controls the stopper unit 12 to cause the stopper unit 12 to release the head region Rft of the strip-shaped film 10 from the clamping (step S102, see FIG. 9B). More specifically, the controller 4 moves up the pressure part 121 to release the head region Rft of the strip-shaped film 10 from the pressurizing by the pressure part 121. By doing so, the strip-shaped film 10 is released from the halting by the stopper unit 12. As a result, the strip-shaped film 10 becomes ready to be drawn in the transport direction Dx.

[0067] After step S102, the controller 4 controls the chuck unit 11 to cause the chuck parts Fp in a pair to start moving from the start position Ps toward the release position Pt while causing the chuck parts Fp in a pair to continue chucking of the head region Rft (step S103). By doing so, the strip-shaped film 10 is pulled by the chuck parts Fp in a pair to be drawn in the transport direction Dx (see FIG. 9C).

[0068] After step S103, the controller 4 controls the chuck unit 11 to stop the chuck parts Fp in a pair temporarily on the way of moving chuck parts Fp in a pair toward the release position Pt (step S104, see FIG. 9C). More specifically, the controller 4 stops the chuck parts Fp in a pair temporarily when the perforated line Pm at a boundary between the head region Rft chucked by the chuck parts Fp in a pair and the next region Rf entirely goes out of a clamping range Rx where clamping is to be done by the stopper unit 12.

[0069] After step S104, the controller 4 controls the stopper unit 12 to cause the stopper unit 12 to clamp the next region Rf connected to the head region Rft across the perforated line Pm (step S105, see FIG. 9D). More specifically, the controller 4 moves down the pressure part 121 to pressurize this next region with the pressure part 121. By doing so, drawing of the strip-shaped film 10 in the transport direction Dx is halted by the stopper unit 12.

[0070] After step S105, the controller 4 controls the chuck unit 11 to restart moving of the chuck parts Fp in a pair toward the release position Pt, thereby tearing off the head region Rft of the strip-shaped film 10 along the perforated line Pm at the boundary with the next region Rf using instantaneous force generated at the time of the restart (step S106, see FIG. 9E).

[0071] As a result of steps S105 and S106, while drawing of the strip-shaped film 10 is stopped by clamping the next region Rf continuous with the head region Rft, it is possible to pull the head region Rft with the chuck parts Fp in a pair. As a result, using tension generated on the strip-shaped film 10 by the pulling, only the head region Rft can be torn off along the perforated line Pm at the boundary with the next region Rf. The torn-off head region Rft becomes one packaging film piece Qf. Furthermore, restarting moving of the chuck parts Fp in a pair generates instantaneous force, and the strip-shaped film 10 is broken easily along the perforated line Pm by using the generated instantaneous force.

[0072] After step S106, the controller 4 controls the chuck unit 11 to cause the chuck parts Fp in a pair to release chucking of the packaging film piece Qf when the chuck parts Fp in a pair reach the release position Pt (step S107, see FIG. 9F). By doing so, the packaging film piece Of is released from chucking by the chuck parts Fp in a pair.

[0073] The controller 4 controls the transport mechanism 2 to start loading of the packaging target 20 (step S201), and causes the transport mechanism 2 to transport the packaging target 20 to a position under the release position Pt and then stop the packaging target 20 (step S202), by the time implementation of step S107 is completed. At this time, the controller 4 moves the loader 21 and the unloader 22 farther from each other to form the space Sw, and stops the packaging target 20 while causing the packaging target 20 to lie astride the space Sw (see FIG. 5). By doing so, the packaging target 20 is placed in a state ready to be packaged with the packaging film piece Qf by the affixing mechanism 3 (a state where the bottom surface of the packaging target 20 is exposed).

[0074] After steps S107 and S202, the controller 4 controls the affixing mechanism 3 to cause the first press unit 31 to press the central portion of the packaging film piece Of against the upper surface of the packaging target 20 (step S301, see FIG. 7A). By doing so, the packaging film piece Of is put into a state where the opposite ends Qfa and Qfb thereof are suspended downward.

[0075] After step S301, the controller 4 controls the affixing mechanism 3 to cause the second press unit 32 to press the opposite ends Qfa and Qfb of the packaging film piece Qf against the bottom surface of the packaging target 20 (step S302, see FIGS. 7B and 7C). By doing so, affixation of the opposite ends Qfa and Qfb is done at the bottom surface of the packaging target 20. As a result, affixation of the packaging film piece Qf to the packaging target 20 (packaging of the packaging target 20 with the packaging film piece Qf) is completed.

[0076] After step S302, the controller 4 controls the transport mechanism 2 to move the loader 21 and the unloader 22 closer to each other, thereby placing the packaging target 20 already packaged on the unloader 22 and unloading the packaging target 20 (step S203).

[0077] The controller 4 thereafter returns to step S101 and step S201 and performs the processing from step S101 and the processing from step S201 repeatedly. In this way, in the packaging apparatus, it is possible to form the packaging film piece Qf and affix the packaging film piece Of to the packaging target 20 (package the packaging target 20 with the packaging film piece Qf) repeatedly and continuously.

[0078] As described above, the packaging film piece forming mechanism 1 according to the present embodiment can form the packaging film piece Qf without using a cutting blade. Thus, it is possible to improve maintenance performance in the packaging film piece forming mechanism 1 and the packaging apparatus. In this way, both improvement of maintenance performance and implementation of continuous operation are achieved in the above-described packaging film piece forming mechanism 1 and packaging apparatus.

[0079] Furthermore, in the present embodiment, when the above-described control processing is repeated, the controller 4 causes the stopper unit 12 to clamp the next region Rf continuous with the head region Rft of the strip-shaped film 10 in step S105, and thereafter causes the stopper unit 12 to continue this state until the processing returns to step S101 to start chucking of this next region Rf (in other words, a new head region Rft generated as a result of tearing-off of the head region Rft).

[0080] According to the described control processing, after the next region Rf becomes the new head region Rft as a result of tearing-off of the head region Rft, the next region Rf is kept clamped by the stopper unit 12 until it is chucked by the chuck parts Fp in a pair. This makes it possible to reliably prevent a curl likely to occur at the head region Rft of the strip-shaped film 10.

[0081] According to the above-described packaging apparatus, it is possible to appropriately adjust a degree of drawing of the strip-shaped film10 by the chuck parts Fp in a pair or the size of the space Sw to be formed between the loader 21 and the unloader 22 (a degree of separation between the loader 21 and the unloader 22) in response to the length of the packaging film piece Qf to be formed (a length between the perforated lines Pm next to each other). Thus, the packaging apparatus according to the present embodiment provides a high degree of freedom in terms of the size or shape of the applicable packaging film piece Qf and further in terms of the size or shape of the packaging target 20.

[0082] The above explanations of the embodiments are nothing more than illustrative in any respect, nor should be thought of as restrictive. The scope of the present invention is indicated by claims rather than the above embodiments. Furthermore, it is intended that all changes that are equivalent to a claim in the sense and realm of the doctrine of equivalence be included within the scope of the present invention.REFERENCE SIGNS LIST1 Packaging film piece forming mechanism

[0084] 2 Transport mechanism

[0085] 3 Affixing mechanism

[0086] 4 Controller

[0087] 10 Strip-shaped film

[0088] 11 Chuck unit

[0089] 12 Stopper unit

[0090] 20 Packaging target

[0091] 21 Loader

[0092] 22 Unloader

[0093] 31 First press unit

[0094] 32 Second press unit

[0095] 41 Storage unit

[0096] 42 Control unit

[0097] Dx Transport direction

[0098] Dy Width direction

[0099] Fp Chuck part

[0100] Gp Sliding transport part

[0101] Hp1 First stopper

[0102] Hp2 Second stopper

[0103] Pm Perforated line

[0104] Ps Start position

[0105] Pt Release position

[0106] Qf Packaging film piece

[0107] Qfa, Qfb End

[0108] Rf Region

[0109] Rft Head region

[0110] Rfa, Rfb End

[0111] Rx Clamping range

[0112] Sw Space

[0113] 111 Upper chuck structure

[0114] 112 Lower chuck structure

[0115] 113 Support

[0116] 113A Beam

[0117] 113B Support arm

[0118] 113C Ball screw

[0119] 113D Handle

[0120] 114 Guide

[0121] 121 Pressure part

[0122] 121A Plate

[0123] 121B Drive part

[0124] 122 Stage

[0125] 123 Ball screw

[0126] 124 Handle

[0127] 311 Press arm

[0128] 312 Drive part

[0129] 321 Press roll

[0130] 322 Drive part

Examples

Embodiment Construction

[1] Configuration of Packaging Apparatus

[0032]FIGS. 1A and 1B are a front view and a block diagram respectively conceptually showing a packaging apparatus according to an embodiment. As shown in these drawings, the packaging apparatus includes a packaging film piece forming mechanism 1, a transport mechanism 2, an affixing mechanism 3, and a controller 4. The configurations of these units will be described below in detail.

[1-1] Packaging Film Piece Forming Mechanism

[0033]FIG. 2A is a perspective view conceptually showing a strip-shaped film 10 used in the packaging film piece forming mechanism 1 according to the present embodiment. As shown in this drawing, the strip-shaped film 10 is an elongated film with a plurality of regions Rf connected to each other continuously across perforated lines Pm. Here, each region Rf is a region to become a film piece (packaging film piece Qf) used for packaging of a packaging target 20 (such as a food container, see FIG. 5). The strip-shaped film 1...

Claims

1. A packaging film piece forming mechanism that allows formation of a plurality of packaging film pieces sequentially using a strip-shaped film including a plurality of regions to become the packaging film pieces and to be connected continuously to each other across a perforated line, in such a manner as to form each of the packaging film pieces from a head region at a head of the strip-shaped film among the regions, the packaging film piece forming mechanism comprising:a chuck unit that includes chuck parts in a pair that chuck corresponding opposite ends of the head region in a width direction, and allows the chuck parts in a pair to move back and forth between a start position at which chucking of the head region is started and a release position separated from the start position toward a direction in which the strip-shaped film is drawable and at which the head region is released from chucking; anda stopper unit that allows drawing of the strip-shaped film to be stopped by clamping the strip-shaped film.

2. The packaging film piece forming mechanism according to claim 1, whereinthe stopper unit is configured in such a manner that, when the stopper unit clamps the strip-shaped film, the opposite ends of the head region in the width direction protrude from the stopper unit to become ready to be chucked by the chuck parts in a pair.

3. A packaging apparatus comprising:the packaging film piece forming mechanism according to claim 1; anda controller, whereinthe controller causes the chuck parts in a pair to chuck the head region of the strip-shaped film at the start position, the controller causes the chuck parts in a pair to continue chucking of the head region and moves the chuck parts in a pair from the start position toward the release position, andon the way of moving the chuck parts in a pair toward the release position, the controller causes the stopper unit to clamp a next region connected to the head region across the perforated line.

4. The packaging apparatus according to claim 3, whereinon the way of moving the chuck parts in a pair toward the release position, the controller stops the chuck parts in a pair temporarily when the perforated line at a boundary between the head region chucked by the chuck parts in a pair and the next region entirely goes out of a clamping range where clamping is to be done by the stopper unit and then causes the stopper unit to clamp the next region, andthe controller thereafter restarts moving of the chuck parts in a pair, thereby tearing off the head region of the strip-shaped film along the perforated line at the boundary with the next region using instantaneous force generated at the time of the restart.

5. The packaging apparatus according to claim 3, whereinafter causing the stopper unit to clamp the next region continuous with the head region chucked by the chuck parts in a pair on the way of moving the chuck parts in a pair toward the release position, the controller causes the stopper unit to continue a state of the clamping until chucking of the next region by the chuck parts in a pair is started.

6. The packaging apparatus according to claim 3, further comprising:a transport mechanism that transports a packaging target; andan affixing mechanism that affixes the packaging film piece formed by the packaging film piece forming mechanism to the packaging target being transported by the transport mechanism.

7. The packaging apparatus according to claim 6, whereinthe transport mechanism includes a loader and an unloader movable closer to and farther from each other in a transport direction, and allows formation of space at a position under the release position at which the packaging target is allowed to lie astride the space by moving the loader and the unloader farther from each other, andthe affixing mechanism includes:a first press unit that allows the packaging film piece to be pressed against an upper surface of the packaging target to put the packaging film piece into a state where opposite ends thereof are suspended downward after the packaging film piece is released from chucking by the chuck parts in a pair at the release position; anda second press unit that allows the opposite ends of the packaging film piece suspended downward to be pressed against a bottom surface of the packaging target.

Images