JP3920646B2 - Packaging equipment - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a packaging device, and more particularly to a packaging device that performs a packaging operation for folding a peripheral portion of a film pressed against a packaged object to the bottom side of the packaged object.
[0002]
[Prior art]
A so-called stretch wrapping apparatus is widely known as an apparatus for covering and sealing an object to be packaged such as fruits and vegetables or food on a tray with a film. In this stretch wrapping apparatus, the object to be packaged is wrapped with the film by pushing up the object to be wrapped against the tensioned film, folding the periphery of the film to the bottom side of the object to be packaged, and heat-sealing.
[0003]
An example of such a stretch wrapping apparatus is disclosed in JP-A-11-208611. Here, the package is pushed up with respect to the film by an elevator (lift mechanism), and the film is folded under the package by a folding mechanism. Specifically, during the folding operation of the left and right folding plates, the left and right folding plates enter under the packaged object as the elevator head tilts. Further, when the left and right folding plates enter under the package, the elevator is lowered and the rear folding plate is advanced to the lower side of the package. In this way, the article to be wrapped in which the left and right and rear edges of the film are folded downward is pushed out to the discharge conveyor on the near side by the pusher. Thereby, the front edge part of the film which contacted the front folding plate is folded under the package. Thus, the film whose periphery is folded under the package is heat-sealed by the heat generation function of the discharge conveyor.
[0004]
[Problems to be solved by the invention]
When the film is folded on the bottom side of the package, if the support state of the package by the support unit of the lift mechanism continues, the support unit of the lift mechanism interferes with the members constituting the folding mechanism. Sometimes. In the packaging device disclosed in the above publication, interference between the elevator and the rear folding plate is avoided by lowering the elevator and then moving the rear folding plate to the lower side of the package. In addition, when the left and right are folded, the elevator head is tilted so that the left and right folded plates enter under the package.
[0005]
However, when the rear folding plate is advanced to the lower side of the article to be packaged after the elevator is lowered, even if the article to be packaged is supported by a support member other than the lift mechanism, the support by the lift mechanism is quickly released. Therefore, the packaged material is in a relatively unstable support state thereafter. In addition, it is effective to adopt a structure in which the elevator head is tilted. In this case, it is difficult to lengthen the support surface of the elevator head (supporting member for the package) in the tilting direction. If the elevator head is configured to rotate around the rotation axis located below the center of the support surface while forming the support surface long in the tilting direction, the end of the support surface is greatly increased upward when the elevator head is tilted. This is because the stability of the lifted package is impaired.
[0006]
The problem of the present invention is that when the member of the folding mechanism enters the bottom side of the packaged object when the film is folded, the lifted mechanism can continue to support the packaged object for as long as possible. An object of the present invention is to provide a packaging device that is not easily impaired in stability.
[0007]
[Means for Solving the Problems]
The packaging device according to claim 1 includes a film holding mechanism, a lift mechanism, and a folding mechanism. The film holding mechanism holds the film in tension. The lift mechanism has a plurality of base members capable of relative movement and a support member extending upward from each base member. The upper part of the support member supports the bottom part of the package. Further, the lift mechanism presses the object to be packaged supported by the support member against the film held by the film holding mechanism. The folding mechanism folds the peripheral portion of the film against which the package is pressed by the lift mechanism to the bottom side of the package. When the film is folded on the bottom side of the article to be packaged, the plurality of base members move relative to each other, and the plurality of base members and the support member contract in plan view.
[0008]
Here, the lift mechanism is composed of a plurality of base members and a support member extending upward from each base member. Then, when the film is folded, the plurality of base members are relatively moved so that the base member and the support member contract in plan view. Thereby, even if the folding member and other members of the folding mechanism enter the bottom side of the article to be wrapped at the time of folding, the base member and the supporting member are contracted so that the article to be packaged is supported by the supporting member. It can be maintained as long as possible. In addition, interference between the support member and the folding mechanism member is avoided by relative movement of the plurality of base members, and it is not necessary to tilt the support member, so that the support member can be formed longer in the avoidance direction. It becomes.
[0009]
The relative movement of the plurality of base members may be only horizontal relative movement, or may be a combination of horizontal relative movement and vertical relative movement, for example, relative movement obliquely in side view. However, it is desirable to employ the latter so that the base member and the support member are contracted so that the support members are displaced vertically. When configured in this manner, some of the support members can be further tilted, or the support member can be more stably supported by reducing the arrangement pitch of the support members. It becomes like this.
[0010]
A packaging device according to a second aspect is the packaging device according to the first aspect, wherein the plurality of base members partially overlap in plan view when the plurality of base members and the support member contract in plan view.
Here, since a part of the plurality of base members is configured to overlap in plan view, that is, the plurality of base members are configured to partially overlap vertically, the base member and the support member are contracted. Easy to design the spring structure. Further, the shape of the base member can be simplified as compared with a case where the plurality of base members are contracted only by horizontal relative movement.
[0011]
A packaging device according to a third aspect is the packaging device according to the first or second aspect, wherein the plurality of base members are a first base member and a second base member disposed behind the first base member. Including. The folding mechanism includes a rear folding member that is disposed rearward and is movable back and forth. In addition, the packaging device according to claim 2 further includes a moving mechanism and a control unit. The moving mechanism moves the rear folding member back and forth. The control unit controls the moving mechanism to move the rear folding member forward, and causes the rear folding member to fold the film to the bottom side of the package. The second base member moves forward when the rear folding member moves forward, and partly overlaps the first base member in the front-rear direction in plan view.
[0012]
Here, when the rear folding member is moved forward, the rear second base member is moved forward and overlapped with the front first base member. Therefore, even if the rear folding member moves to the front and rear position where the second base member originally exists, the package is continuously supported by the support member extending upward from the first base member. Thus, since the base member and the support member are contracted in the front-rear direction as the second base member moves forward and overlaps the first base member, the contracted space (originally the second base member and the support extending upward therefrom) The rear folding member can enter the space in which the member exists, and the packaged object is supported by the lift mechanism as long as the base member and the supporting member contract.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
<Overall configuration and general operation>
A schematic side view, front view, and plan view of a stretch wrapping apparatus according to an embodiment of the present invention are shown in FIGS. Moreover, the control block of the stretch wrapping apparatus 10 is shown in FIG. The stretch wrapping device 10 is a small weighing and packaging device, and is designed to wrap fruits and vegetables with note trays or to wrap foods (products) such as fruits and vegetables contained in soft trays. However, even a product placed on a normal foam tray can be packaged.
[0014]
The stretch wrapping apparatus 10 has a weighing function and a function with a value (a label creation function including a measurement value and a price), but here, the description will be made focusing on the wrapping function of the stretch wrapping apparatus 10.
The stretch wrapping device 10 is a device in which each mechanism is attached to the main body frame 15 and mainly includes a product introduction mechanism 20, a lift mechanism 30, a film transport mechanism 40, a film holding mechanism 50, and a film left and right pushing. A mechanism 60, a left / right folding mechanism 66, and a heat seal / film folding mechanism 70 are provided.
[0015]
When the product G (see the product G on the front side in FIG. 1) is placed on the introduction table 21 of the product introduction mechanism 20 by the operator's hand, the product G is lifted after the product G is weighed by the measuring instrument 29. It is sent to the mechanism 30 (see the commodity G on the rear side of FIG. 1). On the other hand, the film F transported above the lift mechanism 30 by the film transport mechanism 40 is pre-stretched in a state where the front and rear, right and left ends are gripped by the film holding mechanism 50 (see FIG. 10B). When the product G supported by the lift head 32 of the lift mechanism 30 is pushed up with respect to the pre-stretched film F, the product G is covered with the film F while the film F is pushed up. (See FIG. 10C).
[0016]
Thus, the peripheral part of the film F covering the upper side and the side of the product G is folded to the bottom side of the product G by the left and right folding plates 64 and 65 and the rear folding plate 71 (see FIG. 10E). During this folding operation, the left and right folding plates 64 and 65 enter the vicinity of the left and right ends of the bottom of the product G and play a role of supporting the bottom of the product G together with the lift head 32 of the lift mechanism 30. The film F folded on the bottom side of the product G receives heat input from the nichrome wire 81 attached to the front fixing member 72 while being sandwiched between the rear folding plate 71 and the front fixing member 72. Then, heat sealing is performed (see FIG. 13C).
[0017]
The product G thus wrapped with the film F including the heat seal is taken out by an operator's hand, and a label discharged from a pricing mechanism (not shown) is attached.
<Composition of product introduction mechanism 20>
As shown in FIGS. 1 and 4, the merchandise introduction mechanism 20 mainly includes an introduction table 21, an introduction table vertical movement motor 22, and an introduction table longitudinal movement motor 23. The introduction table 21 supports the product G by a plurality of support plates 21a arranged in the left-right direction. These support plates 21a and support members 34b, 36, 37, and 39 (described later) of the lift mechanism 30 shown in FIGS. 6 and 7 are arranged so as to be shifted in the left-right direction. A measuring instrument 29 for measuring the weight of the commodity G placed on the introduction table 21 is disposed below the introduction table 21. The introduction table 21 is connected to an introduction table longitudinal movement motor 23 via a belt, a pulley, or the like, and moves back and forth by the operation of the introduction table longitudinal movement motor 23. Further, the entire longitudinal movement unit including the introduction table 21 and the introduction table longitudinal movement motor 23 is configured to move up and down by the introduction table vertical movement motor 22.
[0018]
When each motor 22 and 23 of the product introduction mechanism 20 is actuated by a command from the control unit 90 to be described later, the introduction table 21 performs a rectangular motion, and the product G placed on the introduction table 21 by the walking beam method is moved to the rear side. It is sent onto the support members 34b, 36, 37, 39 of the lift mechanism 30. Instead of using the two motors of the introduction table vertical movement motor 22 and the introduction table longitudinal movement motor 23, it is also possible to have both of these motors function as a single motor.
[0019]
<Configuration of lift mechanism 30>
The lift mechanism 30 is provided to support the bottom of the product G sent from the product introduction mechanism 20 and lift the product G upward. Further, the lift mechanism 30 plays a role of supporting the bottom of the product G even when the peripheral portion of the film F is folded to the bottom side of the product G, as will be described later.
[0020]
As shown in FIGS. 1, 2, and 4, the lift mechanism 30 mainly includes a vertical rail 30 a that is arranged on the left and right, a slide base 31 and a slider 31 a that move up and down along the vertical rail 30 a, and a link mechanism. 30c, a lift motor 30d that moves the slide base 31 up and down via the link mechanism 30c, and a lift head 32 that is mounted on the front and rear slider 31b on the slide base 31.
[0021]
[Slide table 31 etc.]
The slide table 31 and the slider 31a are integrated by a connecting member extending vertically. The link mechanism 30c rotates around the pin support portion 30b by the operation of the lift motor 30d, and moves the slide base 31 and the slider 31a up and down along the vertical rail 30a.
[0022]
In addition, a front / rear slider 31 b that can move back and forth on the slide table 31 is mounted on the upper surface of the slide table 31. The front / rear slider 31b is urged rearward by a spring member (not shown).
[Lift head 32]
The lift head 32 is an assembly mounted on the upper surface of the front / rear slider 31b, and is mainly fixed to the central base 33, the front / rear base 34, and the central base 33, as shown in FIGS. The left and right center support member 36 and the center support member 37, the center front and rear support member 34 b fixed to the front and rear base 34, and the left and right side front and rear support members 39 are configured.
[0023]
The center base 33 is fixed to a fixed plate 33a fixed to the front / rear slider 31b, a vertical plate 33b extending upward from a central portion in the left-right direction of the fixed plate 33a, and an upper portion protruding left and right, and both left and right ends of the vertical plate 33b Link holding plate 33c.
The front and rear bases 34 disposed in front of and behind the central base 33 are divided into two parts in the front and rear directions, and are supported by the link holding plate 33c via parallel link members 34a. Therefore, the front / rear base 34 is movable in the front / rear direction with respect to the central base 33. Normally, the front and rear bases 34 are supported on the link holding plate 33c by a spring member and a stopper (not shown) so as to be in the state shown in FIG. That is, the front / rear base 34 can be moved only from the state shown in FIG. Specifically, the state changes from the state indicated by the dotted line in FIG. 15B to the state indicated by the solid line.
[0024]
As shown in FIGS. 6 and 7, three left and right center support members 36 are arranged on the left and right sides, respectively, and are supported by a support base 35 extending upward from the vertical plate 33b of the center base 33. . The left-right center support member 36 includes a support portion 36b that supports the bottom of the product G, a frame 36a that is fixed to the lower surface of the support portion 36b, and a pin 36c that supports the lower ends of the frame 36a on the support base 35. It consists of and. As shown in FIG. 16, these left and right side central support members 36 receive a force when left and right folding plates 64 and 65 and left and right pushing members 61 and 62, which will be described later, come in, and rotate around the pin 36c. Move and fall inside. However, the frame 36a is normally urged so that the state shown in FIG. 6 is maintained by a spring member (not shown).
[0025]
The center support member 37 is a pair of members provided between the left and right side center support members 36 as shown in FIG. These central support members 37 are composed of a fixed portion 37a fixed to the vertical plate 33b of the central base 33, and a support portion 37b mounted on the upper portion of the fixed portion 37a. The support portion 37b that supports the bottom of the product G and the fixing portion 37a are integrated, and the support portion 37b of the center support member 37 is not tilted.
[0026]
As shown in FIGS. 5 and 15, the center support member 37 and the left and right side center support member 36 form a concave shape in a side view combined with the center front and rear support member 34 b and the left and right side front and rear support members 39. For this reason, the product G is stably supported.
As shown in FIGS. 6 and 7, three left and right front and rear support members 39 are arranged on the left and right with respect to the respective front and rear bases 34. The twelve left and right side front and rear support members 39 each include a fixing member (first member) 38 that extends upward from the upper surface of the front and rear base 34 and a support portion (second member) that is supported by the fixing member 38 and on which the product G is placed. 39b. As shown in FIG. 6, the fixing member 38 is fixed to the upper surface of the front and rear base 34, and a pair of vertical grooves 38 a are formed from the center portion to the lower portion, and a locked portion 38 b is formed at the upper end. A frame 39a including two pin support portions extending downward from the support portion 39b is integrally fixed to the lower surface of the support portion 39b. As shown in FIGS. 5 and 6, the pin support portion of the frame 39a supports two upper and lower pins 39c and 39d. The upper pin (locking portion) 39c is locked to the locked portion 38b of the fixing member 38 from above. The lower pin 39d is arranged so as to move along the longitudinal groove 38a of the fixing member 38 (see FIGS. 6 and 16). Further, the upper surface of the support portion 39b has a slight angle with respect to the horizontal plane, and serves as a support surface that supports the bottom portion of the product G.
[0027]
As shown in FIGS. 15A and 16, the left and right side front and rear support members 39 having such a configuration contract vertically when a force along the horizontal direction acts on the support portion 39 b from the outside. Specifically, when a force acts on the support portion 39b from the outside, the pin 39c locked from above on the locked portion 38b of the fixing member 38 is displaced inward, and the support portion 39b and the frame 39a fall. As a result of the fall, the support portion 39b and the fixing member 38 move mainly in the vertical direction, and the left and right side front and rear support members 39 contract vertically. From another viewpoint, the support surfaces of the left and right side front and rear support members 39 that support the product G are lowered by the fall of the support portion 39b. When the support portion 39b and the frame 39a are dropped, the lower pin 39d moves along the vertical groove 38a. Further, since the pin 39c is urged toward the front and rear base 34 (downward) by the spring 39e, the dropping operation of the support portion 39b and the frame 39a is performed quickly.
[0028]
The state in which the support portion 39b is dropped (the state shown in FIG. 16) automatically returns to the original state when the entire lift head 32 is lowered along the vertical rail 30a. When the lift head 32 is lowered, a return member (not shown) enters the lift head 32 through the gap between the front and rear bases 34 divided into two parts, relatively lifts the frame 39a, and engages the upper pin 39c with the fixed member 38. Return to top of stop 38b. Accordingly, the lift head 32 that is lowered always has the pin 39c as shown in FIG. 6 placed on the locked portion 38b.
[0029]
As shown in FIG. 6, the center front / rear support member 34 b is a member that is fixed to the center portion in the left-right direction of each front / rear base 34 and extends upward from the front / rear base 34. These central front and rear support members 34b include a fixed portion 34d fixed to the front and rear base 34, and a support portion 34c attached to the upper portion of the fixed portion 34d. The support part 34c that supports the bottom of the product G and the fixing part 34d are integrated, and the central front and rear support member 34b does not shrink vertically like the left and right side front and rear support members 39.
[0030]
<Configuration of film transport mechanism 40>
The film transport mechanism 40 is a mechanism for transporting the film F cut to a predetermined size above the product G supported by the lift mechanism 30 and holding the film F in tension. The film transport mechanism 40 mainly moves the roll holding part 41 that rotatably supports the film roll R, the front clamp 54 that holds the front end of the film F fed from the film roll R, and the front clamp 54 to move back and forth. And a front clamp moving mechanism. The front clamp moving mechanism includes a front clamp forward / backward movement motor 56a (see FIG. 4), a belt mechanism, a front clamp support member, and the like. Here, the front clamp 54 moves back and forth by operating the front clamp forward / backward movement motor 56a. The front clamp 54 grips or separates the front end portion of the film F by turning on / off the front clamp solenoid switch 56b shown in FIG.
[0031]
When a command to convey the film F is issued from the control unit 90, the front side clamp 54 moves rearward and grasps the leading end of the film F that is fed from the film roll R and reaches the vicinity of the rear side clamp 53. Then, the front clamp 54 moves forward with the front end of the film F being gripped, so that the film F is positioned above the lift mechanism 30.
[0032]
<Configuration of Film Holding Mechanism 50>
The film holding mechanism 50 mainly includes a front clamp 54 and a front clamp moving mechanism, which are also components of the film transport mechanism 40, a rear clamp 53 and a rear clamp moving mechanism, a left clamp 51, a right clamp 52, and a later-described film. It is comprised from the left-right pushing member moving mechanism which is also a component of the film left-right pushing mechanism 60 to perform.
[0033]
The rear clamp 53 grips and separates the rear end of the film F by turning on and off the rear clamp solenoid switch 55b shown in FIG. 4, and moves back and forth by the rear clamp moving mechanism. The rear clamp movement mechanism includes a rear clamp forward / backward movement motor 55a (see FIG. 4), a belt mechanism, a rear clamp support member, and the like.
[0034]
As shown in FIG. 9, the left clamp 51 and the right clamp 52 are provided below left and right pressing members 61 and 62, which will be described later, and the film F is sandwiched between the left and right pressing members 61 and 62. Grip. That is, the left clamp 51 and the right clamp 52 move upward to grip the film F by contacting the left and right pushing members 61, 62, and move downward to leave the film F by moving away from the left and right pushing members 61, 62. Release the grip. Therefore, in order to move the left clamp 51 and the right clamp 52 up and down, as shown in FIG. 4, a left clamp up-and-down motor 51a and a right clamp up-and-down motor 52a are provided. When the left clamp vertical movement motor 51a and the right clamp vertical movement motor 52a operate, the left clamp support base 51b and the right clamp support base 52b that support the left clamp 51 and the right clamp 52 move up and down.
[0035]
The left clamp 51 and the right clamp 52 are supported by a left clamp support base 51b and a right clamp support base 52b so as to be movable left and right by a predetermined distance. Then, the left clamp 51 and the right clamp 52 can slightly move up and down with respect to the left clamp support base 51b and the right clamp support base 52b so that the left clamp 51 and the right clamp 52 do not draw an arcuate locus due to the left-right movement. It is configured as follows. Therefore, when the left and right push members 61 and 62 move to the left and right in a state where the left clamp 51 and the right clamp 52 are pressed against the left and right push members 61 and 62 from below, the left clamp 51 and the right clamp 52 follow the movement. . In other words, the left and right pushing member moving mechanism that moves the left and right pushing members 61 and 62 to the left and right also serves to move the left clamp 51 and the right clamp 52 to the left and right.
[0036]
The film holding mechanism 50 plays a role of gripping the peripheral portion of the film F when the product G is pushed up by the lift mechanism 30 and is in a state where the film F is stretched immediately before the product G is pushed up. Perform a pre-stretch operation. By this pre-stretching operation, the clamps 53, 54, 51, 52 holding the peripheral portion of the film F are horizontally moved outward, and the film F is stretched by a predetermined amount.
[0037]
<Structure of film left / right pushing mechanism 60>
The film left and right pushing mechanism 60 is composed of left and right pushing members 61 and 62 and a left and right pushing member moving mechanism that moves these pushing members 61 and 62 to the left and right. The left and right pushing member moving mechanism includes a film pushing motor 63a shown in FIG. 4, a belt mechanism, a support member that supports the left and right pushing members 61 and 62, and the like. The film pushing motor 63a is operated by a command from the control unit 90, and moves the left and right pushing members 61 and 62 to the left and right.
[0038]
Further, the left and right pushing members 61 and 62 can grip the film F by sandwiching the film F between the left clamp 51 and the right clamp 52, and act as a part of the clamp. The left and right pushing members 61 and 62 are formed with long holes for strengthening the clamping action. Since the same applies to any of the pressing members 61 and 62, here, the elongated hole 61a formed in the left pressing member 61 shown in FIG. 9B will be described. The long hole 61 a is formed long in the front-rear direction, and has a size such that a protruding portion 51 c protruding upward from the upper surface of the left clamp 51 can be inserted. When the left clamp 51 moves upward and comes into close contact with the pushing member 61, the protrusion 51c of the left clamp 51 enters the long hole 61a, and the film F enters between the protrusion 51c and the long hole 61a. The movement of F in the left-right direction is strongly restricted. Thus, the presence of the protrusion 51c and the long hole 61a enhances the degree of gripping the film F by the clamp 51 and the pushing member 61.
[0039]
<Configuration of left / right folding mechanism 66>
The left and right folding mechanism 66 mainly includes left and right folding plates 64 and 65, and a left and right folding motor 68a (see FIG. 4) for moving the left and right folding plates 64 and 65 to the left and right. The left and right folding motor 68a moves the folding plates 64 and 65 to the left and right via a belt mechanism, a support member that supports the folding plates 64 and 65, and the like.
[0040]
The left and right folding plates 64 and 65 are arranged above the left and right pushing members 61 and 62, and the product G is placed during a film folding operation by the rear folding plate 71 described later.
<Configuration of Heat Sealing / Film Front / Rear Folding Mechanism 70>
The heat sealing and film front / rear folding mechanism 70 operates after the right and left ends of the film F covering the product G are folded under the product G, and the rear end of the film F is folded under the product G. This is a mechanism for sandwiching the film F under the product G and heat-sealing.
[0041]
The mechanism 70 mainly includes a rear folding plate 71 and a rear folding plate moving mechanism, a rear clamp 53 and a rear clamp moving mechanism (described above), a front fixing member 72, a front clamp 54 and a front clamp moving mechanism (described above). ) And a nichrome wire 81 and a thermistor 82 attached to the front fixing member 72.
The rear folding plate 71 is disposed between the left and right pressing members 61 and 62 and the left and right folding plates 64 and 65 in the height direction, and folds the film F from the back to the bottom side of the product G and fixes the front side. The film F is sandwiched between the members 72 and a pressing force necessary for heat sealing is applied to the film F. The rear folding plate moving mechanism includes a rear folding plate moving motor 71a (see FIG. 4), a belt mechanism, a support member that supports the rear folding plate, and the like. When the rear folding plate moving motor 71a is actuated by a command from the control unit 90, the rear folding plate 71 moves back and forth.
[0042]
The rear folding plate 71 has a roughened front surface of the main body 71c in the range shown in FIG. 3 and a rough surface. Further, as shown in FIG. 8, a bakelite member 71 c is attached to the tip of the rear folding plate 71. The bakelite member 71c is made of a material having appropriate hardness, heat resistance, wear resistance, insulation, and the like. With such a configuration, the portion of the rear folding plate 71 that comes into contact with the film F when the film F is folded is in a state in which the film F is hardly adhered.
[0043]
The front side fixing member 72 is fixed to the main body frame 15. The front side fixing member 72 includes an aluminum plate 72a, a stainless plate 72b, and a roller 72c. The aluminum plate 72a is disposed at a position sandwiched between the stainless plate 72b and the roller 72c. A nichrome wire 81 is attached to the rear surface of the aluminum plate 72a (the surface facing the rear folding plate 71), and the nichrome wire 81 is more forward than the rear surface of the stainless steel plate 72b and the rear end of the roller 72c. The stainless steel plate 72b and the roller 72c are arranged so as to be retracted. The nichrome wire 81 (height dimension 2 mm) is attached to the rear surface (height dimension 5 mm) of the aluminum plate 72a via an insulating tape.
[0044]
Further, in order to estimate the amount of heat applied to the film F from the nichrome wire 81 by measuring the temperature of the aluminum plate 72a, a thermistor 82 as a temperature sensor is embedded in the aluminum plate 72a.
Furthermore, the aluminum plate 72 a is divided into two parts on the left and right sides, and absorbs the elongation corresponding to the thermal expansion of the nichrome wire 81.
[0045]
<Details of operation of stretch wrapping apparatus 10>
Next, of the operations of the stretch wrapping apparatus 10, the operation of folding the film F from the left and right to the bottom side of the product G and the operation of folding the film F from the rear to the bottom side of the product G and heat-sealing the film F are detailed. Explained.
(Left / right folding and pushing)
As shown in FIG. 10A, when the film F is transported above the lift mechanism 30 by the film transport mechanism 40, the left and right clamps 51, 52 are lifted up and between the left and right pushing members 61, 62. To grip the left and right portions of the film F. At this time, the front and rear portions of the film F are also held by the front and rear clamps 53 and 54.
[0046]
Next, the left and right pushing members 61 and 62 and the left and right clamps 51 and 52 following them are opened outward, and the film F is pre-stretched in the left and right direction (see FIG. 10B). At this time, the film F is also prestretched in the front-rear direction. The lift mechanism 30 raises the product G placed on the support members 34b, 36, 37, and 39 of the lift head 32 with respect to the film F that has been pre-stretched and has no wrinkles, and the film F is pushed up by the product G. (See FIG. 10C). At this time, the product G is in a state where the film F is covered upward by the film F with the film F pushed up.
[0047]
As shown in FIG. 10 (c), when the product G is in a state of pushing up the film F, the left and right folding plates 64 and 65 enter the inside in advance to fold the film, and the left and right pushing members 61 are slightly delayed. 62 and the rear folding plate 71 also enter the inside. The left and right folding plates 64 and 65 stop moving when they enter the inside to a position where the bottom of the product G can be supported. On the other hand, the left and right push-in members 61 and 62 and the left and right clamps 51 and 52 that follow the left and right push-in members 64 and 65 prevent the excessive tension from acting on the film F due to the movement of the left and right folding plates 64 and 65. Then, the left and right clamps 51 and 52 are lowered at an appropriate position to release the right and left portions of the film F (see FIG. 10D).
[0048]
Even after releasing the grip of the left and right portions of the film F, the left and right pushing members 61 and 62 continue to move inward, and finally move to the inside of the left and right folding plates 64 and 65 and stop ( (Refer FIG.10 (e)). FIG. 11 shows the positional relationship between the left and right folding plates 64 and 65 and the left and right pushing members 61 and 62, and the rear folding plate 71 and the front side fixing member 72 in plan view.
[0049]
In the left and right folding operation, the support of the product G by the lift mechanism 30 continues to be supported by the support portion 34c of the center front and rear support member 34b and the support portion 37b of the center support member 37, and the left and right side center support member 36 is supported. The support by the support part 36b and the support part 39b of the left and right side front and rear support members 39 is replaced with support by the left and right folding plates 64 and 65 (see FIG. 16). When the left and right folding plates 64 and 65 enter the inner side, the support portion 36b of the left and right side central support member 36 is pushed by the left and right folding plates 64 and 65 in order from the outer side, and rotates around the pin 36c. Move and fall inside. When the left and right folding plates 64 and 65 enter the inside, the support portions 39b of the left and right side front and rear supporting members 39 are pushed by the left and right folding plates 64 and 65 in order from the outside, as described above. Fall.
[0050]
[Post-folding operation and heat sealing operation]
The product G and the film F that are in the state shown in FIG. 10 (e) or FIG. 11 by the above left and right folding operation and pushing operation are in the state shown in FIG. 12 (a) in a side view. That is, the product G includes a support portion 34c of the central front and rear support member 34b, a support portion 37b of the central support member 37 (here, the product G is not supported because the product G is short in the front and rear directions), and the left and right folding plates 64. , 65.
[0051]
In the rear folding operation, the rear folding plate 71 first moves forward, and the rear clamp 53 moves forward with a slight delay. Thereafter, the rear clamp 53 moves forward in accordance with the movement of the rear folding plate 71 so that excessive tension does not act on the film F (see FIG. 12B).
When the rear folding plate 71 hits the support portion 34c of the central front and rear support member 34b on the rear side of the lift head 32, the entire lift head 32 starts to move forward by being pushed by the forward force from the rear folding plate 71 ( (Refer FIG.10 (c)). At this time, the front / rear slider 31 b to which the lift head 32 is fixed moves forward on the slide base 31.
[0052]
Following this, as shown in FIG. 10 (d), the commodity G also starts to move forward. Further, as the lift head 32 and the product G move forward, the front clamp 54 starts moving backward in order to keep the tension of the film F on the front side of the product G properly.
As shown in FIG. 10 (d), when the support portion 34c of the front center front / rear support member 34b hits the front fixing member 72, the lift head 32 receives a compressive force from both the front and rear, and the lift head 32 is moved back and forth. Start shrinking in the direction. Specifically, as shown in FIGS. 15A and 15B, forces from both the front and rear sides act on the front and rear base 34 via the support portion 34c and the fixing portion 34d, and the state of the parallel link member 34a changes. Both the front and rear bases 34 move obliquely downward so as to approach the central base 33. By this movement, as shown in FIG. 15B, the support part 39b in the fall state enters the lower side of the support part 36b in the collapsed state. Further, by this movement, the fixing plate 33a of the central base 33 and the front and rear bases 34 are overlapped vertically (overlapping in plan view).
[0053]
FIG. 13A and FIG. 14 show the product G supported by the lift head 32 and the folding plates 64 and 65 in a state of being contracted back and forth. Here, the product G is supported only by the folding plates 64 and 65 and the support portion 37b of the central support member 37 of the lift head 32. Since the support portion 34c of the center front and rear support member 34b of the lift head 32 moves obliquely downward as the lift head 32 contracts back and forth, the support portion 34c does not support the bottom portion of the product G.
[0054]
As shown in FIG. 13 (a), when the lift head 32 has been contracted back and forth, the entire lift head 32 is lowered along the vertical rail 30a according to a command from the control unit 90. As shown in FIG. 13B, the rear folding plate 71 and the rear clamp 53 that continue to move forward enter the space generated by the lowering of the lift head 32. That is, as the lift head 32 descends, there is no obstacle to the rear folding plate 71 and the rear clamp 53 entering under the product G, and the rear folding plate 71 and the rear clamp 53 move further forward. Also at this time, the product G that receives a forward force from the rear folding plate 71 via the film F slides on the left and right folding plates 64 and 65 and continues to move forward.
[0055]
Finally, the rear folding plate 71 hits the front fixing member 72, specifically, the bakelite member 71c of the rear folding plate 71 hits the nichrome wire 81 of the front fixing member 72, and the front film F and the rear side The film F is heat-sealed under the product G by pressing force and heat input from the nichrome wire 81 (see FIG. 13C). Note that the grip of the film F by the rear clamp 53 and the front clamp 54 is released at the time of heat input from the nichrome wire 81 or just before that. This is to prevent a change in tension of the film F during heat input.
[0056]
Thereafter, the rear folding plate 71 and the rear clamp 53 return to the rear (see FIG. 13 (d)), and the product G covered with the film F and heat-sealed has the left and right folding plates 64, 65. It will be in the state supported by the front part.
<Configuration of Control Unit 90 and Characteristic Control by Control Unit 90>
The control unit 90 controls the operation of each mechanism 20, 30, 40, 50, 60, 66, 70 of the stretch wrapping apparatus 10. The control unit 90 includes a storage unit 91 such as a RAM.
[0057]
The storage unit 91 stores information about the product G and information about the film F collected by external input, manual input, or input from the measuring instrument 29 or the like.
[Control on left and right folding and pushing operations]
The control unit 90 controls the film pushing motor 63a and the left and right folding motor 68a based on the control data including the property information of the product G and the film F in the storage unit 91, and the left and right pushing members 61 and 62 The movement amount and the movement timing of the left and right folding plates 64 and 65 are optimal for the product G and the film F. Control data includes data relating to whether or not the product G includes a tray, data relating to the shape of the product G or tray, data relating to the dimensions of the product G or tray, data relating to the rigidity of the product G or tray, and data relating to the size of the film F. Data, and data on the type of film F, etc., but here, film size, film type, tray depth / width / height, tray softness, product G shape (round, etc.), product Control data including information on the height of G, whether the product G is placed on a hard tray or a soft tray, or whether the product G is packaged without a tray is used.
[0058]
Further, the timing for releasing the right and left portions of the film F in the left and right pushing operation, that is, the timing for lowering the left and right clamps 51 and 52 is also controlled based on the above control data.
[Control for back folding operation]
The control unit 90 controls the rear folding plate moving motor 71a, the rear clamp forward / backward movement motor 55a, and the front clamp forward / backward movement motor 56a based on the property information of the product G and the film F in the storage unit 91. Specifically, the rear clamp forward / backward movement motor 55a that moves the rear clamp 53 in accordance with the movement of the rear folding plate 71 by the rear folding plate moving motor 71a is controlled so that excessive tension does not act on the film F. In order to keep the tension of the front film F that changes due to the forward movement of the product G in an appropriate range, the front clamp forward / backward movement motor 56a that moves the front clamp 54 is controlled. Thereby, it is suppressed that excessive tension acts on the film F and a hole is opened in the film F or an excessive force acts on the product G.
[0059]
[Control for heat sealing operation]
When the front film F and the rear film F are sandwiched between the rear folding plate 71 and the front fixing member 72 below the product G, the control unit 90 has a large voltage or current (impulse) that lasts for a very short time. ) Is passed through the nichrome wire 81 to heat the film F. That is, here, an impulse seal that can change the amount of heat input to the heat seal portion with good responsiveness is employed.
[0060]
Then, the control unit 90 determines at least one of the current value, voltage value, number of times, and energization time of the impulse flowing through the nichrome wire 81 based on the temperature measured by the thermistor 82 embedded in the aluminum plate 72a of the front fixing member 72. To change. For this reason, the heat sealing of the film F can be performed with a heat input amount that is not excessive or insufficient.
For example, when the temperature of the front fixing member 72 rises or falls due to a change in the surrounding environment, the temperature change is measured by the thermistor 82, so the nichrome wire 81 is controlled so that the heat seal is properly performed. be able to. Specifically, when the ambient temperature is low in winter, the temperature of the aluminum plate 72a is lowered, and the amount of heat necessary for heat sealing may be insufficient. Therefore, the impulse seal is controlled to compensate for this.
[0061]
<Characteristics of stretch wrapping device 10>
(1)
In the stretch wrapping apparatus 10, the lift head 32 of the lift mechanism 30 includes a central base 33 and front and rear bases 34, and support members 34 b, 36, 37, and 39 that extend upward from the bases 33 and 34. Then, during the rear folding operation, the central base 33 and the front and rear bases 34 are moved relative to each other so that the bases 33 and 34 and the support members 34b and 37 contract in plan view.
[0062]
Thus, even if the rear folding plate 71 and the rear clamp 53 enter the bottom side of the product G during the rear folding operation, the bases 33 and 34 and the support members 34b and 37 are contracted, so that the support portion of the central support member 37 is supported. The state which supports the goods G by 37b can be maintained as long as possible. Further, the relative movement of the center base 33 and the front and rear bases 34 avoids interference between the support members 34b and 37 and the rear folding plate 71 and the rear clamp 53, and the support part 34c of the center front and rear support member 34b is moved back and forth. Therefore, the support part 34c of the center front / rear support member 34b can be formed long in the front / rear direction. In the case of adopting a configuration in which the support portion 34c is tilted, if the support portion 34c is lengthened back and forth, the end portion of the support portion 34c is lifted when the support portion 34c is tilted and the stability of the support state of the product G is lost.
[0063]
(2)
In the stretch wrapping device 10, the left and right folding plates 64 and 65 enter the inside in the left and right folding operation, and the horizontal force is applied from the folding plates 64 and 65 to the support portion 36 b and the left and right side front and rear support. When acting on the support part 39b of the member 39, the support part 36b falls inward and comes out of the moving path of the folding plates 64 and 65, and the supporting part 39b falls and comes off the moving path of the folding plates 64 and 65. In other words, the support portion 39b having a height higher than that of the support portion 36b is not a structure that falls down, but has a structure in which the support member 39b falls laterally with respect to the fixing member 38 and falls. For this reason, the arrangement | positioning pitch of the left-right direction of the support part 39b can be set small. In this way, since the bottom of the product G is stably supported, even if the product G is a naked product without a tray or a product placed on a soft tray, the product G is hardly deformed or damaged. The packaging is made without it.
[0064]
(3)
In the stretch wrapping apparatus 10, when the left and right folding plates 64 and 65 enter the inside in the left and right folding operation, and a horizontal force acts on the support portion 39 b of the left and right side front and rear support members 39 from the folding plates 64 and 65. The pin 39c that has been locked to the locked portion 38b of the fixing member 38 is displaced inward, and the support portion 39b and the frame 39a are dropped. That is, the upper surface of the support portion 39b of the left and right side front and rear support members 39 has a structure that avoids interference with the folding plates 64 and 65 by falling horizontally and dropping. For this reason, the upper surface of the support part 39b that supports the product G hardly moves upward, and the risk of the product G being deformed or damaged is reduced.
[0065]
[Other Embodiments]
(A)
In the above embodiment, the lift head 32 of the lift mechanism 30 is moved forward by pushing the rear folding plate 71. However, the lift head 32 can be moved back and forth by a dedicated drive device. It is.
[0066]
(B)
In the above embodiment, the front and rear bases 34 are moved obliquely downward with respect to the central base 33 and the lift head 32 is contracted back and forth. It is also possible to adopt a configuration that contracts back and forth.
[0067]
(C)
In the above-described embodiment, the entire lift head 32 moves forward on the slide base 31, but the lift head 32 is directly fixed to the slide base 31, and the lift head 32 does not move back and forth as a whole (planar surface). It is also possible to adopt a configuration that does not move. Also in this case, the rear front and rear bases 34 move obliquely downward with respect to the central base 33, so that the rear folding plate 71 and the rear clamp 53 enter the bottom side of the product G during the rear folding operation. The state where the product G is supported by the support portion 37b of the central support member 37 can be maintained as long as possible.
[0068]
【The invention's effect】
In the present invention, the lift mechanism is composed of a plurality of base members and support members extending upward from the respective base members, and the base members and the support members are viewed in plan view by relatively moving the plurality of base members when the film is folded. To shrink. Thereby, even if the folding member and other members of the folding mechanism enter the bottom side of the article to be wrapped at the time of folding, the base member and the supporting member are contracted so that the article to be packaged is supported by the supporting member. It can be maintained as long as possible. In addition, interference between the support member and the folding mechanism member is avoided by relative movement of the plurality of base members, and it is not necessary to tilt the support member, so that the support member can be formed longer in the avoidance direction. It becomes.
[Brief description of the drawings]
FIG. 1 is a schematic side view of a stretch wrapping apparatus.
FIG. 2 is a schematic front view of the stretch wrapping apparatus (a view taken in the direction of arrows II-II in FIG. 1).
FIG. 3 is a schematic plan view of a stretch wrapping apparatus.
FIG. 4 is a control block diagram of the stretch wrapping apparatus.
FIG. 5 is a side view of a lift head of the lift mechanism.
FIG. 6 is a front view of a lift head of the lift mechanism.
FIG. 7 is a top view of a lift head of the lift mechanism.
8 is a view taken along arrow VIII-VIII in FIG. 3;
FIG. 9A is a diagram showing parameters in the initial position adjustment of the left and right clamps.
(B) The figure which shows the junction part of a left clamp and a left pushing member.
FIG. 10 is a diagram showing a left and right folding operation and a pushing operation.
FIG. 11 is a schematic plan view when the left and right folding is completed.
FIG. 12 is a diagram showing a post-folding operation.
FIG. 13 is a diagram showing a post-folding operation and a heat sealing operation.
FIG. 14 is a schematic plan view of one plane during a rear folding operation.
FIG. 15A is a side view showing a state change of the lift head of the lift mechanism during the left and right folding and pushing operations.
(B) The side view showing the state change of the lift head of the lift mechanism at the time of back folding.
FIG. 16 is a front view illustrating a state change of the lift head of the lift mechanism during the left and right folding and pushing operations.
[Explanation of symbols]
10 Stretch packaging equipment
30 Lift mechanism
32 Lift head
33 Central base (base member; first base member)
34 Front and rear bases (base member; second base member)
34b Center front / rear support member (support member)
36 Left-right center support member (support member)
37 Center support member (support member)
39 Left / Right Front / Rear Support Member (Support Member)
50 Film holding mechanism
70 Heat sealing and film front / rear folding mechanism (folding mechanism)
71 Rear folding plate (rear folding member)
71a Rear folding plate moving motor (moving mechanism)
90 Control unit
F film
G Product (packaged item)

Claims (3)

A film holding mechanism for holding the film in tension;
A plurality of base members capable of relative movement and a support member that extends upward from each of the base members and supports a bottom portion of the package object, and holds the package object supported by the support member on the film A lift mechanism that presses against the film held by the mechanism;
A folding mechanism that folds the periphery of the film against which the object to be packaged is pressed by the lift mechanism to the bottom side of the object to be packaged;
With
When the film is folded on the bottom side of the article to be packaged, the plurality of base members move relative to each other, and the plurality of base members and the support member shrink in plan view.
Packaging equipment. When the plurality of base members and the support member contract in plan view, the plurality of base members partially overlap in plan view.
The packaging device according to claim 1. The plurality of base members include a first base member and a second base member disposed behind the first base member,
The folding mechanism has a rear folding member that is arranged rearward and movable back and forth,
A moving mechanism for moving the rear folding member back and forth;
A control unit for controlling the moving mechanism, moving the rear folding member forward, and folding the film to the bottom side of the package by the rear folding member;
Further comprising
The second base member moves forward when the rear folding member moves forward, and partially overlaps the first base member in the front-rear direction in plan view.
The packaging device according to claim 1 or 2.

Images