JPH089366B2 - Stretch wrapping machine - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wrapping machine, and more particularly to a stretch wrapping machine for holding a tip of a roll film by a gripper, pulling it out for a predetermined length, and stretch-wrapping an object to be wrapped placed on a wrapping section. .

[0002]

2. Description of the Related Art Conventionally, a roll film is of a type in which a gripper pulls out and cuts a predetermined length in parallel with the conveying direction of the object to be wrapped, and the cut film stretch-wraps the object to be wrapped. In the stretch wrapping machine, the pull-out length of the roll film can be adjusted in order to change the size of the film according to the size of the article to be wrapped.

[0003]

However, in the conventional stretch wrapping machine, even if the size of the cut film can be changed according to the size of the article to be packed, the cut film is cut after the cut film. Since the end is configured to be held at a fixed position on the rear side of the packaging unit, centering between the cut film and the article to be packaged has not been performed. Therefore, in the conventional stretch wrapping machine, the folding margins before and after the cut film do not have the same size, and the difference in the folding margin affects the finish of the packaging, and as a result, the size of the product that can be wrapped is limited. I was sick. Further, in the case of a small packaged object, more than necessary film was wasted for packaging.

According to the present invention, the stretch wrapping machine as described above is provided with a cut film and a means capable of rationally centering the object to be packed in the front-rear direction. The purpose is to increase the film thickness and prevent the film from being wasted.

[0005]

[Means for Solving the Problems] In order to solve the above-mentioned problems, a stretch wrapping machine according to the first aspect holds a roll film at its front end with a gripper and draws it out by a predetermined length.
In a packaging machine that stretch-wraps an object to be packaged that has been brought into the packaging section by folding the front and rear and both sides of the film, a front gripper that holds the leading end of the film extending from the roll film and pulls out a predetermined length, A rear gripper that holds the rear end of the film pulled out by the front gripper, and a cutter that cuts the film held by the rear gripper from the back of the holding part,
A film holder that holds the tip of the cut roll film, and the front gripper and the rear gripper are both moved in the film withdrawing direction, and the center of the film sandwiched by both grippers is the center of the packaging part into which the object to be packaged is carried. And a avoidance mechanism that positions the rear gripper at a position that does not interfere with the movement of the front gripper when the front gripper holds the front end of the roll film held by the film holder. It is a thing.

Further, the invention according to claim 2 is provided with a film folding plate at each of the front and rear of the film transport direction of the packaging unit, and the front and rear folding plates are directed toward the center of the packaging unit on which the article to be packaged is placed. It is characterized in that the film tension-coated on the object to be packaged is folded by being moved respectively and sandwiched at the center of the bottom of the object to be packaged.

[0007]

According to the stretch wrapping machine of claim 1, the front gripper clamps the front end of the roll film held by the film holder, and then moves in parallel with the longitudinal direction of the film so that the front end of the clamped film is held. Pull out a specified length. The rear gripper holds the rear end of the film pulled out by the front gripper. The cutter cuts the film pulled out as described above after the rear gripper. As a result, the roll film is cut into a predetermined length, and the front and rear thereof are held by being sandwiched by the front and rear grippers. Further, the leading end of the roll film cut by the cutter is held by the film holding body and waits for being held by the front gripper as described above in the next packaging process.

Both the front and rear grippers for holding the cut film move together in the drawing-out direction of the film by the operation of the transfer mechanism, and move the cut film to the wrapping portion where the object to be packed is placed, and Align the center with the center of the packaging. After the centering of the cut film as described above, the cut film is tension-covered on the object to be packaged placed in the wrapping section as in the conventional case, and the front and rear sides and both sides of the tensioned film are folded. Stretch packaging is performed.

After the stretch wrapping is completed, the front gripper moves toward the roll film side for the next wrapping, and as described above, the leading end of the roll film held by the film holder is again held and pulled out. . At this time, the rear gripper moves to a position where the movement of the front gripper is not hindered by the avoidance mechanism.

Further, according to the stretch wrapping machine of claim 2, when the cut film is centered on the wrapping portion and then the cut film is tension-coated on the article to be wrapped placed on the wrapping portion. Then, the folding plates provided at the front and rear of the packaging unit move toward the center of the packaging unit. As a result, the front and back of the film tension-coated on the object to be packaged are folded into the object to be adhered and closely adhered at the center of the object to be packaged.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 shows a stretch wrapping machine embodying the present invention, in which a carry-in section A on which a product 1 to be packaged is placed is a machine frame 3
A wrapping section B is provided on the upper surface of the machine frame 3 and is provided on the front side of the machine frame 3, and the film 2 for wrapping the product 1 is horizontally drawn and stretched. Then, a carrier C for transporting the product 1 received from the carry-in section A to the packaging section B is supported by a drive mechanism D, and is movable in the horizontal and vertical directions in the machine frame 3 so that the carrier C can be moved. After the horizontal movement section D1 of the drive mechanism D horizontally moves to the carry-in section A on which the product 1 is placed, in the carry-in section A, the D2 vertical operation section D of the drive mechanism D is moved.
The product 1 is vertically moved by 2 to receive the product 1 from the carry-in section A. Further, the carrier C with the product 1 placed on the upper surface is horizontally moved by the horizontal movement section D1 toward the lower side of the packaging section B where the film 2 is horizontally drawn and stretched, and then the vertical movement section D2 wraps the product. Vertically move toward the film 2 of the part B. Through these series of operations, the carrier C is moved to the loading section A.
From the carry-in section A to the wrapping section B by moving the product 1 horizontally and vertically from the carry-in section A to the wrapping section B and carried into the carry-in section A by the carrier C.
The product 1 is conveyed to the packaging unit B, and the product 1 is pushed up on the film 2 and packaged.

As shown in FIG. 2, the carrying-in section A is formed by arranging a plurality of mounting rods 4 in parallel at appropriate intervals, and connecting and supporting one end of them to form a substantially comb-like shape. When the receiving portion 34 of the carrier C described later passes between the above-mentioned placing rods 4, the article 1 placed on the placing rods 4 is received. The carry-in section A is attached and supported to the weighing machine 5 with a built-in load cell arranged on the front surface of the machine frame 3 via the supporting rod 6, whereby the weight of the product 1 placed on the placing rod 4 is measured. A label printer (not shown) issues a label on which the weight data and the weight data and the price calculated based on the weight data are printed.

A front gripper F, which holds the leading edge of the film 2 and pulls out a predetermined length from the film supply device E, is arranged in the packaging section B so as to be horizontally movable above the front of the machine frame 3 on the loading section A side. In addition, after holding the rear end of the film 2 pulled out to the upper part in the machine frame 3, the rear gripper G
Is horizontally movably arranged on the rear side of the machine frame 3 in the direction facing the front gripper F. The film pulled out from the roll film held by the film supply device E is inserted between the film holding plates 61 and 62 and horizontally drawn toward the packaging section B. The above-mentioned film holding plates 61 and 62 are formed in a comb shape at the leading edge and are installed in a state of being stacked immediately before the rear gripper G in the standby state, and the film 2 is inserted between both plates 61 and 62. Forming a gap. Further, the drawing length of the film 2 drawn through the film holding plates 61, 62 is set to a predetermined dimension depending on the size of the product 1. The film pulled out by the front gripper F for a predetermined length has the rear end thereof sandwiched by the rear gripper G, and then the film holding plate 6
It is cut by a cutter arranged at the tips of the parts 1, 62.

In the packaging section B, left and right clamp devices H (see FIG. 3) for holding the left and right side edges of the film 2 are arranged on both sides of the machine frame 3 orthogonal to the drawing direction of the film 2.
The four side edges of the film 2 pulled out from the film supply device E are clamped by the devices F, G, H to tension the film 2.

The front gripper F and the rear gripper G described above are fixed clamp plates 7 and 8 on the upper side, and a movable clamp plate on the lower side which is opened and closed with respect to the fixed clamp plates 7 and 8 by a cylinder (not shown). It is composed of 9 and 10. The front gripper F and the rear gripper G are individually fixedly supported to the timing belts 13 and 14 that rotate in the front-rear direction by the unique motors 11 and 12 arranged on both sides of the machine frame 3, respectively. It moves forward and backward by 11 and 12 (see Fig. 2). That is, the above-mentioned motor 11 and timing belt 13 are the front gripper F.
Of the transfer mechanism P1 of the motor 12, the timing belt
Reference numeral 14 constitutes a transfer mechanism P2 for the rear gripper G.
Further, the product 1 is ascended and supplied to the film 2 by the carrier C above the devices F, G and H, and then the front and rear ends and the left and right side edges of the film 2 are attached to the product 1. Folding devices I and J are provided which operate so as to be folded toward the bottom side.

As shown in FIG. 3, the front-rear folding device I divides two front and rear folding plates 15 extending in the width direction of the machine frame 3 into a front gripper F side and a rear gripper G side, respectively, and front and rear horizontal. It is movably arranged. The folding plate 15 is wound around the both sides of the machine frame 3 in the front-rear direction. The both ends of the plate are fixedly connected to the drive chain 17 rotated by the motor 16 via the connecting arms 18 to move in synchronism. The film 2 is made to come close to each other at speed.
Fold the front end and the rear end of the product into the bottom side of the product 1 at the same time. still,
One of the front and rear folding plates 15, the front folding plate in the illustrated example
A heater 19 for heat sealing is embedded in the folded edge of 15 (see FIG. 3).

On the other hand, the left and right folding device J has a strip-shaped folding plate 20 extending between the folding plates 15 before and after standing by in an open state.
The machine frame 3 with the front and rear folding plates 15 positioned.
It is arranged horizontally on both the left and right sides. The left and right folding device J has guide bushes provided at its front and rear ends.
23 is slidably inserted along two rotary shafts 22 which are rotatably supported by the chain 17 and the sprocket 21, and the rear ends of the left and right folding plates 20 are attached to the rear gripper G.
It is fixed to the chain 24 arranged on the side through a connecting arm 25. Then, the left and right edges of the film 2 are simultaneously folded into the bottom side of the product 1 by moving the motors 26 close to each other at a moving speed synchronized with each other.

The left and right clamp device H has an elevating frame 28 connected to the upper ends of rods of an air cylinder 27 installed below the left and right folding plates 20 standing by in an open state, and has a substantially L-shaped cross section with respect to the elevating frame 28. Spring formed movable clamp plate 29
By attaching and supporting 30 via a guide pin 31 that is mounted elastically, the left and right folding plates 20 are movably supported in the opening direction. Then, the movable clamp plate 29 is attached to the cylinder 27.
The left and right side edges of the film 2 are sandwiched by being lifted up and brought into contact with the lower surfaces of the left and right folding plates 20.

The carrier C receives the merchandise 1 placed on the carry-in section A and having been weighed, and at the same time, conveys the merchandise 1 to the lower side of the packaging section B, and the film 2 pulled out from the lower side and stretched to the packaging section B. The head base 33 is formed by forming upright portions 32 at intervals that pass between the comb-blade-shaped mounting rods 4 that form the carry-in portion A.
A receiving portion 34 for receiving the product 1 is fixed on each standing portion 32 of the head base 33. The carrier C is supported by a drive mechanism D via a support member 35 and is moved in the machine frame 3 in the horizontal and vertical directions by the operation of the drive mechanism D.

A drive mechanism D installed in the lower part of the machine casing 3
Is for moving the carrier C from the carry-in section A to the packing section B, and is for horizontally moving the carrier C supported by the support member 35 between the carry-in section A and the packing section B. The operating section D1 and the vertical operating section D2 for vertically moving the carrying table C at the loading section A and the packaging section B respectively.
Consists of The support member 35 includes guide struts 36 on both sides of the machine frame 3 erected with the lower end fixed, and the guide struts 36 on both sides.
A vertically moving frame having a rectangular shape in a plane, which is horizontally arranged in the machine frame 3 by supporting the frame portions on both sides so as to be slidable vertically.
And guide grooves provided on the inner surfaces of both side frames of the vertical movement frame 37.
A front and rear moving plate 39 is supported in the moving frame 37 so as to be slidable in the front and rear direction by fitting and locking both side portions to the 38. Then, the head base 33 of the carrier C is mounted and supported on the front-rear moving plate 39 via the supporting legs 40 formed in an L shape. According to this, even if the length of the support rod 6 is not made so long by the support leg 40, the carriage C can enter under the carry-in section A (FIG. 4).

The horizontal motion section D1 is a cam 44 mounted on the output shaft 43 of the deceleration box 41 driven by the operation of the motor 42.
And a swing arm 46 which is linked to the cam 44 and swings up and down with the rear end shaft support portion 45 as a fulcrum by the rotation of the cam 44. Further, the horizontal operation part D1 forms a substantially L-shaped arm body, and the corner portions thereof are pivotally supported by a rotating shaft 47 installed on the bottom of the machine frame 3 and the swing end of the swing arm 46 and the short side. A starting arm 49, which is connected to the end portion via a connecting arm 48, and a starting arm in a connecting elongated hole 50 which is hung from the lower surface of the front-rear moving plate 39 of the supporting member 35 and formed over substantially the entire length thereof. The vertical arm 51 is provided with a long side end portion of 49, which is fitted and connected slidably along the long hole 50. Then, the horizontal motion part D1 is moved up and down by the swing arm 46 along the cam floor of the cam 44 which is rotated by the main motor 42, and the long side of the starting arm 49 with the swing shaft 47 as a fulcrum. The carrier C is moved from the carry-in section A to the lower side of the packaging section B via the front-back movement plate 39 by causing the front-back movement to the side (FIGS. 5 and 6), and further below the packaging section B. From below to below the loading section A (from the state of FIG. 8 to the state of FIG. 9).

On the other hand, the vertical motion section D2 includes a cam 52 mounted on the cam shaft 43, a swing arm 54 which is connected to the cam 52 and swings up and down with a rear end shaft support 53 as a fulcrum, and this swing. The swinging end of the arm 54 and the vertical moving frame 37 of the support member 34
And a connecting arm 55 whose end portions are connected and attached. Then, a cam rotated by the main motor 42.
Along with the vertical swing motion of the swing end of the swing arm 54 along the cam floor of 52, the carrier C is transferred through the vertical moving frame 37 to the loading section A.
And the packaging section B are configured to move up and down respectively. That is, in the carry-in section A, the state of FIG. 1 rises to the state of FIG. 5, and in the packaging section B, the state of FIG. 6 rises to the state of FIG. 7, and from the state of FIG. 7 to the state of FIG. And will descend.

The stretch wrapping machine constructed as described above is
The packaging of the product 1 proceeds by sequentially operating each device and each mechanical unit at a predetermined timing by sequence and timer control by a control unit (not shown) including a microcomputer. The packaging process will be described below with reference to FIGS. 5 to 9 and 10 to 23. First, an operator puts the product 1 on the carry-in section A and turns on the operation switch of the apparatus. Then, the carrier C initially waiting under the loading section A is lifted by the vertical operation section D2, and the loading section A
Receive product 1 from (Fig. 5). At the same time, the carrier table C moves to the lower part of the packaging unit B by the horizontal operation unit D1 while keeping its height, and conveys the product 1 to a predetermined position below the packaging unit B (FIG. 6). As shown in FIG. 10, the film holding plates 61 and 62 are arranged in parallel with the conveying operation of the product 1.
The front end of the film 2 held between the front gripper F
Grips and starts the pulling operation, and pulls out the film 2 in the direction of the packaging portion B by the length set corresponding to the size of the product 1 (FIG. 11). At this time, the rear gripper G stands by at the rear side of the film holding plates 61 and 62, and is positioned so as not to interfere with the movement of the front gripper F that holds the leading edge of the film 2.

Next, the rear gripper G waiting on the rear side of the film holding plates 61 and 62 advances to the front of the cutter K and holds the stretched film 2 (FIG. 12, FIG. 12).
(Fig. 13). Further, before or during the centering operation of the cut film 2, the cut film 2 is stretched in the longitudinal direction by a predetermined amount by the gripper F and the rear gripper G to perform pre-stretching. After that, the film 2 is cut by the cutter K after the rear gripper G (FIG. 14). The film 2 thus cut is in a state in which the front and rear edges are sandwiched by the front and rear grippers G and F. After the film 2 is separated, the front gripper F and the rear rear gripper G move at a synchronized speed at a predetermined timing, and the center of the film 2 sandwiched between the grippers and the center of the packaging part B are separated. It stops when they match (FIG. 15). Thereby, the cut film 2 and the packaging portion B are centered. After that, as shown in FIG. 16, the left and right edges of the film 2 are clamped by the left and right clamp devices H and the left and right folding plates J, and at the same time, as shown in FIG.
By stretching the film 2 to the right and left by a predetermined amount as shown by 7, the film 2 drawn out to the wrapping portion B is pre-stretched and expanded, and the four side edges of the front end, the rear end, and the left and right side edges are held.

On the other hand, the carrier C moved to the lower side of the wrapping section B rises toward the film 2 expanded in the wrapping section B by the operation of the vertical operation section D2 as shown in FIG.
The product 1 is supplied to the packaging section B. While the product 1 is rising, the upper part of the product 1 placed on the carrier C passes through the photoelectric sensors 65a and 65b installed at a predetermined height below the packaging section B. At this time, the photoelectric sensors 65a and 65b output detection signals, and based on this, the left and right folding plates 20 move slightly inward and give the film 2 an appropriate slack (FIG. 18). Immediately after that, the film 2 is pushed up from below by the product 2 (FIG. 19), and the left and right folding plates 20 of the left and right folding device J are further pushed.
Moves in the folding direction (Fig. 20) and the air cylinder 27
The movable clamp plate 29 supported by the above is separated from the left and right folding plates 20 to release the left and right side edges of the film 2 (FIGS. 8 and 2).
0). Then, the left and right folding plates 20 move toward the center,
Stop at a slight gap in the center of the bottom of the product 1 (Fig. 21). At about the same time as this, the front and rear folding plates 15 start moving in the folding direction, and in the form of following this, both front and rear grips F, G move in the direction in which they approach each other.
The folded edges of the front and rear folding plates 15 collide with each other to perform heat sealing (FIGS. 9 and 22), and the packaging of the product 1 is completed. As a result, the film 2 tension-coated on the product 1 is folded back equally to the bottom surface side of the product 1, and is closely attached at the center of the bottom portion of the product 1 through the folding margins having the same front and rear dimensions. The product 1 that has been heat-sealed and packaged is taken out from the front and back folding plate 15 which is kept in a closed state by the operator and a label or the like is attached (FIG. 23).

When the series of packaging operations described above is completed, the carrier C, the front gripper F and the rear rear gripper G are returned to the initial standby position, and the same operation is repeated thereafter to package the product 1. . In the case of the above embodiment,
When the front gripper F holds the leading edge of the film 2 held between the film holding plates 61 and 62 and pulls it out,
The rear gripper G is configured so as not to interfere with the movement of the front gripper F by standing by behind the film holding plates 61 and 62, but the invention is not limited to this. For example, the clamp plates 8 and 10 above and below the rear gripper G may be configured to stand by in the vertical direction, respectively.

[0027]

As described above, according to the present invention, the cut film sandwiched between the front and rear grippers is moved toward the packaging portion on which the object to be packaged is placed to center the packaging film and the cut film. Therefore, even if the size of the film is changed according to the size of the object to be packaged, the folding margins before and after the film that encloses the object to be packaged can always be the same size to improve the packaging finish. The size of the packaged object can also be increased.
Further, even in the case of a small-sized packaged object, it is possible to package the film with an optimal film length for the size of the packaged object, so that it is possible to prevent the film from being wasted.

[Brief description of drawings]

FIG. 1 is a side view showing a stretch wrapping machine embodying the present invention.

FIG. 2 is a perspective view showing front and rear grippers in a packaging unit.

FIG. 3 is a perspective view showing a main part of the front, rear, left, and right folding devices in the packaging unit.

FIG. 4 is a perspective view of a main part showing a carrier and a drive mechanism thereof.

FIG. 5 is a schematic view showing a state in which a carrier receives an object to be transported from a carry-in section.

FIG. 6 is a schematic view showing a state in which a carrier table on which an object to be packaged is placed is moved to a position below a packaging unit.

FIG. 7 is a schematic view showing a state in which a carrier is raised toward a film and an article to be packaged is supplied to a packaging section.

FIG. 8 is a schematic view showing a packaging process of a packaged object by the left and right folding devices.

FIG. 9 is a schematic view showing a packaging form of an article to be packaged by the front and rear folding device.

FIG. 10 is a schematic view showing a front end of a film held by a film holding plate portion.

FIG. 11 is a schematic view showing a state in which the film is drawn out.

FIG. 12 is a schematic view showing a state in which the rear gripper is moved to the front of the cutter.

FIG. 13 is a schematic view showing a state where a film is sandwiched by a rear gripper.

FIG. 14 is a schematic view showing a state in which a film is cut by a cutter.

FIG. 15 is a schematic view showing a state in which a film sandwiched by front and rear grippers is centered with respect to a packaging unit.

16A and 16B are schematic views showing the left and right folding device in which the left and right side edges of the film are held, FIG. 16A being a plan view and FIG.
Is a vertical front view.

FIG. 17 is a schematic view showing a left and right folding device showing a state where the film is tensioned left and right, (a) is a plan view,
(B) is a vertical sectional front view.

FIG. 18 is a schematic view of the packaging unit showing the process of raising the transfer table.

FIG. 19 is a schematic view of a packaging unit showing a state where a film is pushed up by a product.

FIG. 20 is a schematic view of a wrapping unit showing a state in which the left and right sides of the film are released.

FIG. 21 is a schematic view of a packaging unit showing a state in which the left and right folding devices are closed.

22A and 22B are schematic views of the packaging unit showing a state in which the front and rear folding plates are closed, where FIG. 22A is a plan view and FIG.

FIG. 23 is a schematic view of a packaging unit showing a state where a product is picked up.

[Explanation of symbols]

1 ... Merchandise (Item to be packaged) 2 ... Film 5 ... Measuring instrument 15 ... Front / rear folding plate 61, 62 ... Film holding plate A ... Carry-in section B ... Packaging section C ... Conveyor stand D・ ・ ・ Drive mechanism E ・ ・ ・ Film supply device F ・ ・ ・ Front gripper G ・ ・ ・ Rear gripper K ・ ・ ・ Cutters P1, P
2 ... Transfer mechanism

Claims (2)

[Claims] 1. A wrapping machine for stretch-wrapping an object to be wrapped that has been carried into a wrapping section by gripping the front end of a roll film with a gripper, pulling it out for a predetermined length, and folding the front and rear and both sides of the film. A front gripper that holds the leading end of the film extending from and pulls out a predetermined length, a rear gripper that holds the rear end of the film pulled out by the front gripper, and a film that is held by the rear gripper. A cutter that cuts after the nipping portion, a film holding body that holds the leading end of the cut roll film, the front gripper and the rear gripper are both moved in the film drawing direction, and the center of the film nipped by both grippers is covered. A transfer mechanism that aligns the package with the center of the package where the package is loaded, and A stretch wrapping machine, comprising: an avoiding mechanism that positions the rear gripper at a position that does not interfere with the movement of the front gripper when the front gripper holds the front end of the roll film held by the rum holder. 2. A film folding plate is provided at each of the front and rear of the packaging section in the film transfer direction, and both front and rear folding plates are moved toward the center of the packaging section on which the article to be packaged is placed, respectively. The stretch-wrapping machine according to claim 1, wherein a tension-coated film is folded over the package and sandwiched at the center of the bottom of the package.