JPH0120247Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a packaging machine using a stretch film, and more particularly, to a film feed-out and transfer device in this type of packaging machine.

(Prior art and its technical issues) Many years have passed since stretch film packaging machines have been put into practical use, but recently they have not only been developed with the original function of wrapping with stretch film, but also how to make them look beautiful. Users and manufacturers are also becoming more interested in packaging.

However, conventionally, according to Japanese Utility Model Application Publication No. 50-102762, when the film is fed out from the film supply source along the film transport path, both ends of the film are held by clamps and the film is fed out in an expanded shape to both sides.
A device is disclosed in which a stretch film is pre-stretched in the width direction.

However, in the above-mentioned conventional device, the film is stretched only in the width direction while the side edges are held by clamps, so although the film itself stretches in the width direction, a plurality of streaks extending in the width direction are generated. The streaks remain on the surface of the packaged item even after packaging, causing wrinkles, which is not always satisfactory in terms of a beautiful packaging finish.

In view of these conventional circumstances, the present invention solves the above-mentioned problems by stretching the film in the transport direction and the width direction while the film is being transported, thereby improving the packaging finish and simplifying the stretching mechanism. The purpose of the present invention is to provide a device with a simple structure and fewer failures.

(Technical Means for Solving the Problems) The film feeding device of the present invention includes a first feeding device that draws out and transfers the film from a film supply source along a film transfer path, and a first feeding device that draws out and transfers the film from the film supply source, and a film feeding device that feeds out the film from the device. A second feeding device is provided to feed and transfer the film while holding the side end portions of the film.The second feeding device is composed of a pair of left and right conveyors, and both conveyors are arranged in a wide-spread shape with respect to the direction in which the film travels. It is characterized in that the transfer speed is set faster than the transfer speed of the first feeding device.

(Function) According to the present invention, the first feeding device draws out and transfers the film from the film supply source, and the second feeding device further feeds out the film and transfers it to a predetermined packaging position. During the transfer, the film is stretched in the transfer direction due to the difference in transfer speed between the two devices, and the film is also stretched in the width direction due to the divergent arrangement of both conveyors of the second feeding device.

(Effects) According to the present invention, the film that is fed out and transported is stretched in the transport direction and spread in the width direction, so that the occurrence of streaks due to stretching on the film surface is significantly reduced, and packaging is improved. Gives a good finish.

Furthermore, since a separate extension mechanism from the feeding device is not required for the extension in the transfer direction and the width direction, the device is simple, compact and lightweight, and costs can be reduced. In addition, the number of assembled parts is reduced, which improves assembly work efficiency, reduces the causes of failure, and facilitates maintenance.

Furthermore, since a separate stretching mechanism is not required, there is no need for a stretching process separate from the feeding process, and the throughput can be improved.

(Example) Embodiments of the present invention will be explained with reference to the drawings.

FIG. 3 is a longitudinal sectional side view of the stretch film wrapping machine of the embodiment, and in the figure, numeral 10 indicates the machine frame of the stretch film wrapping machine.

As shown in FIGS. 3 to 5, this machine frame 10 is constructed into a substantially rectangular parallelepiped, and the left side in FIG.
0b, and the right side is the back surface 10c.

There is a loading port 10 approximately in the center of the front surface 10b of the machine frame 10.
a is opened, and the machine frame 1 is opened from before the loading port 10a.
A carry-in conveyor 11 is provided throughout the interior of the vehicle.

The carry-in conveyor 11 is composed of a pusher conveyor 12 and a belt conveyor 14, and conveys the packaged items to a predetermined position on an elevator head 13 disposed at the discharge end side of the pusher conveyor 12.

As shown in FIG. 4, the pusher conveyor 12 is
The chain 12 is connected between a pair of sprockets 12a, 12a provided in front of the loading port 10a and a pair of sprockets 12'a, 12'a provided inside the machine frame 10.
b, 12b, and the chain 12b, 12b
A pusher 12c, 12c is provided at a predetermined position, respectively, and one article to be packaged is carried in each time the chains 12b, 12b rotate half a rotation. The pusher conveyor 12 pushes the packaged items placed on the conveyance surface 12d with pushers 12c and conveys them.
A roller 14a of the belt conveyor 14 is provided nearby so as to freely rotate.

The belt conveyor 14 is located at the rear of the elevator head 13 (FIGS. 3 and 4) in correspondence with the roller 14a.
A roller 14b is freely rotatable on the right side of the figure, and six belts 14c,
14c... is strung up. The belt conveyor 14 transports the packaged items brought in by the pusher conveyor 12 to the rear end side of the elevator head 13.

The elevator head 13 is installed on a head mounting base 13b supported by a pair of arms 13a, 13a that swing up and down, and is preset in accordance with the rotation of the motor M1 that drives the carry-in conveyor ₁₁ . It moves up and down at the same timing. This timing is set by a timing cam (not shown) provided in a mechanism for transmitting the power of the motor _M1 to the head mount 13b. The elevator head 13 is used to push up the items to be packaged carried in by the carry-in conveyor 11 to a predetermined packaging position 9. Therefore, the lower end position of the elevator head 13 is set at approximately the same height as the conveying surface 12d of the carry-in conveyor 11, and the upper end position is set at approximately the same level as the packaging position 9, that is, the horizontal folding plates 17, 17 and the front folding plate 16, which will be described later. The position will be set to

Incidentally, as in the conventional packaging machine, the object to be packaged is pushed up by a stretch film while being pushed up to the packaging position 9 by the elevator head 13, so that the upper surface is covered by the stretch film, and this will be explained later. This will be explained in detail.

In addition, the carry-in conveyor 11 is replaced by the pusher conveyor 1.
The reason why the conveyors 12 and 14 are combined instead of using only one of the belt conveyors 12 and 14 is that when assembling and manufacturing the packaging machine, just by reassembling the same parts, the direction of conveyance of the product after wrapping can be changed. This packaging machine can be manufactured in a forward direction rather than a backward direction (in the case of the embodiment), and is described in detail in Japanese Utility Model Application Publication No. 188101/1988, which was previously filed by the applicant of the present application.

The elevator head 13 and head mounting base 1
3b is formed into a slit shape as shown in FIGS. 4 and 5, and when the elevator head 13 is moved up and down, the belts 14c and 1 of the belt conveyor 14 are
4c... from coming into contact with the elevator head 13 and the head mounting base 13b.

The elevator head 13 has a plurality of small blocks 1
3c, 13d, 13e..., and each small block 13c, 13d, 13e... is provided to be able to rise and fall freely in response to a force applied from a predetermined direction, and is biased upright by a coil spring (not shown) or the like. has been done. The small block 13c receives a force from above in FIG. 4, and the small block 13d receives a force from below in FIG.
The small blocks 13e are constructed so as to be tilted by a force from the left side in FIG. 4, so that the stretch film folding operation described later can be carried out without any hindrance.

In addition, 15 in FIG. 3 is a positioning plate provided at the rear of the elevator head 13.
The object to be packaged brought in in step 4 is positioned with reference to the rear end.

Around the packaging position 9, as shown in FIG.
A pair of horizontal folding plates 17, 17', a front folding plate 16 and a rear folding roller 18 are provided, and these form an opening through which the packaged items pushed up by the elevator head 13 pass.

The horizontal folding plates 17, 17' are used to perform horizontal folding in the left-right direction, and are provided so as to be slidable in the vertical direction in FIG. 4, and are configured to slide in conjunction with each other in opposite directions.

The front folding plate 16 performs forward folding after the above-mentioned horizontal folding is completed, and is provided so as to be slidable in the left-right direction in FIG. 4, and is driven independently of the horizontal folding plates 17, 17'. An unloading pusher 30 is disposed above the front folding plate 16.

The carry-out pusher 30 transfers the packaged items that have been subjected to the front folding and the horizontal folding to the rear folding roller 18.
During this movement process, the back-folding roller 18 performs back-folding to complete the packaging. The packaged items that have been wrapped are placed on heat belt 1.
While being transferred at step 9, the bottom folded portion is heat welded.

The above is a description of the packaging mechanism mainly for transporting objects to be packaged in the packaging machine of the embodiment, and the stretch film supply section and feeding device will be described below.

The stretch film supply section is located on the right side of the packaging machine, as shown in FIG. 20 in the figure,
20' and 21, 21' are supporting rollers that support the stretch film rolls A ₁ and A ₂ , respectively;
The structure is such that two types of stretch film rolls A ₁ and A ₂ having different widths can be selectively used. FIG. 5 shows a case where a film roll A ₁ is used, and the stretch film A _{' 1} unwound from the roll A 1 is wound around the right support roller 20' and pulled out, and passed through the end detection roller 40. It is inserted between the upper and lower feeding belts 27, 27', 28, 28'. The belts 27, 27', 28, 2
8' constitutes a film advance device 60, 60' (FIG. 6).

Next, to briefly explain the feeding and transport of the stretch film _A'1 , the belts 27, 27',
The film inserted between 28 and 28' is fed out by the rotation of belts 27, 27', 28 and 28'. The film is fed out to the front end of the belts 27, 27', 28, 28' (left side in Fig. 5).
Film A' ₁ is then held between clip groups 7, 7' (to be described later) and rubber belts 6d, 6'd on both sides, and is unrolled to a length necessary for packaging. ' ₁ is cut to the required length.
The cut film A″ ₁ is placed in the elevator head 13.
After being transferred until the upper predetermined position, that is, the center of the film _A''1 coincides with the center of the elevator head 13, it stops and enters a standby state.

The film feeding device consisting of clip groups 7, 7' and rubber belts 6d, 6'd is located at a height between the wrapping position 9 and the lower end position of the elevator head 13 as shown in FIG. As shown, they are arranged to face each other so as to sandwich the packaging position 9 when viewed from above.

The film feeding device will be explained below with reference to FIGS. 1 and 2.

A pair of adjuster screws 1 and 2 are rotatably provided on the machine frame 10 from the front side 10b to the back side 10c, and a hypoid gear 1c is attached to the end of each adjuster screw 1 and 2 on the side of the back side 10c. 2c are provided respectively.

Further, a rotating shaft 3 is disposed along the back surface 10c of the machine frame 10, and the hypoid gears 1c,
Hypoid gears 3a and 3b meshing with gear 2c are each fixed.

A handle 3c is provided at the right end of the rotating shaft 3 on the outside of the machine frame 10, and by rotating the handle 3c, the adjusting screws 1 and 2 can be rotated via the rotating shaft 3. .

The adjusting screw 1 has threaded portions 1a, 1b,
The adjusting screw 2 is formed with threaded parts 2a and 2b, respectively, and the threaded parts 1a and 2b shown in the upper part of FIG.
2a has a close pitch, and the lower threaded portions 1b and 2b have reverse threads and a coarse pitch. As a result, as will be described later, when the distance between the chain conveyors 6 and 6' is changed in accordance with the width of the stretch film used, the amount of movement of the chain conveyor 6 is smaller than that of the chain conveyor 6'.

This is because the direction in which the packaged items are carried out is taken into account. That is, in this embodiment, after completing the left and right horizontal folding and front folding of the packaged item, when carrying out the packaged item in the opposite direction to the carry-in direction, the package is folded backward to complete the packaging. This is because drastically changing the amount causes twitching, wrinkles, etc., which is not desirable. Moreover, the threaded portion 1a,
1b has a generally coarser pitch than threaded portions 2a and 2b.

In the figure, D is the distance between the centers of the packaging position 9, d is the distance on the adjusting screw 2 side, and C is the film stretching rate (hereinafter referred to as pre-stretch degree).
Then, the degree of pre-stretching C at the center of the packaging position 9 is C=D-d/d. In order to keep this pre-stretch degree C constant regardless of the film width, it is necessary to change the widening angle of the chain conveyors 6, 6' in accordance with the film width.
The pitches of a and 2b are set to satisfy these.

The apparatus of this embodiment is configured such that the degree of pre-stretching C at the center of the packaging position 9 is approximately 0.05 (5%).

Each screw portion 1 of the adjusting screw 1, 2
A, 1b, 2a, 2b are equipped with adjusting blocks 4a, 4b, 5a, which are fitted with nuts.
5b is arranged. A chain conveyor 6 is disposed across the adjusting blocks 4a, 5a on the back side 10c, and a chain conveyor 6' is disposed across the adjusting blocks 4b, 5b on the front side 10b.

In the figure, assuming that the axis passing through the center of the elevator head 13 from left to right is the X-X' axis, and the axis passing through the vertical direction is the Y-Y' axis, the chain conveyors 6, 6' are arranged in the film transport direction with respect to the X-X' axis. It is arranged in a wide-end shape. Furthermore, the chain conveyors 6 and 6' have substantially symmetrical structures, and the chain conveyor 6 will be explained in detail below.

As shown in FIG. 2, a mounting instruction member 50 is rotatably provided on the adjusting block 4a, and its rotation range is regulated by an engagement pin 51. The adjustment block 5a has a mounting instruction member 5.
2 is provided to be rotatable and movable within a small range in the front-rear direction, and its rotation range and movement range are limited to the engagement pin 5.
3. With this configuration, it is possible to change the divergence angle of the chain conveyor 6.

A mounting board 54 is mounted and fixed to the mounting members 50, 52 by a plurality of screws 54a, 54a, . . . . Sprockets 6a and 6b are rotatably disposed at each end of the mounting board 54, and an endless chain 6c is stretched between the sprockets 6a and 6b.

An endless rubber belt 6d with a circular cross section is provided around the outer periphery of the chain 6c. As shown in detail in FIGS. 7 to 10, a plurality of substantially U-shaped mounting plates 7a, 7a, . . . are provided at predetermined intervals on the side surface of the chain 6c on the back surface 10c side.

The mounting plates 7a, 7a... each pass through each connecting bush of the chain 6c, and hexagonal socket bolts 7b, 7b...
A clip 7 is rotatably attached to each mounting plate 7a via a shaft 7c.

The clip 7 has a lever shape that swings around a mounting portion 7e formed in the center. Clip 7
A semicircular recess 7d that fits into the rubber belt 6d is formed on the rubber belt 6d side, and the other end is used as an operating piece 7f for opening and closing the clip 7.
It acts as.

As shown in FIG. 10, a support plate 55 is attached to the upper part of the mounting board 54 over a predetermined area with screws 56, and a protrusion 55a integrally formed on this support plate 55 is connected to a chain. 6c to guide and support the central recess, and the other protrusion 55b engages with the engagement hook 7g integrally formed on the mounting plate 7a to guide and support the mounting plate 7a. There is.

Next, a mechanism for opening and closing the clip 7 will be explained. The state in which the clip 7 and the rubber belt 6d are in contact as shown by the solid line in FIG. 10 is called the closed state, and the state in which the clip 7 and the rubber belt 6d are separated as shown in the dashed line is called the open state.

The opening/closing mechanism of the clip 7 includes a fixed guide member 8a,
8b and movable guide members 21, 22, and 23.

Fixed guide members 8a and 8b are disposed near the outside of the sprocket 6b on the film supply section side, and are configured to sandwich the side end portion of the film _A'1 .

The clip 7 moves under the chain 6c in a substantially closed state by balance and reaches the fixed guide member 8a.

The fixed guide member 8a is used to turn the clip 7 over the chain 6c in an open state, and as shown in FIG. 8, its lower left end portion engages with the operating piece 7f of the clip 7. It is formed into a smooth inclined surface to guide this.

As shown in FIG. 1, three movable guide members 21, 22, and 23 are arranged near the outside of the chain conveyor 6, one on the left side, one in the center, and one on the right side. Each movable guide member 21, 22, 23 has a substantially similar structure, and the movable guide member 22 in the center will be explained.

As shown in FIG. 11, the movable guide member 22 includes an upper pressing plate 22a and a lower pressing plate 22b.
The upper pressing plate 22a is configured to be substantially continuous with the lower pressing plates 21b and 23b of No. 3, and the upper pressing plate 22a is configured to be slightly shorter than the lower pressing plate 22b.

The lower side of the upper pressing plate 22a is fixed to the side of the lower pressing plate 22b by spot welding or the like, and the operating piece 7f of the clip 7 is placed in the space 22c formed by the upper pressing plate 22a and the lower pressing plate 22b. You will be guided.

The lower pressing plate 22b has biasing means 22d, 22'd such as springs disposed below near both ends thereof, and is constantly biased upward.

As shown in FIG. 10, the lower pressing plate 22b is formed into a U-shape in cross section, and this side surface is connected to the pin 22.
It is connected to the tip of the operating rod 22f of the solenoid S by e. The solenoid S is arranged approximately at the center of the lower pressing plate 22b and is screwed to the side plate 58.

When the solenoid S is not energized, the operating rod 22f is in a slidable state, and the lower pressing plate 22b is urged upward by the urging means 22d and 22'd, as shown by the solid line in FIG. Become. Therefore, the operating piece 7f of the clip 7 is pressed upward by the lower pressing plate 22b. Therefore, the recess 7 of the clip 7
d is fitted with the rubber belt 6a to form a film.
Now hold the side edge of A′ ₁ firmly.

When the solenoid S is energized, the operating rod 22f is attracted by the solenoid S and moves downward, as shown by the dashed line in FIG. 10, and the upper pressing plate 22a moves downward.

The actuating piece 7f in the space 22c is the upper pressing plate 22a.
The clip 7 is pushed down and moved downward, and the clip 7 becomes open.

Next, the drive mechanism of the chain conveyor 6 will be explained.

As shown in FIGS. 1 and 2, a gear 24 is coaxially fixed to the sprocket 6a on the opposite side from the film supply section, and a drive shaft 25 is disposed parallel to the adjusting screw 1. A gear 26 that meshes with the gear 24 is provided on the shaft 25.

The gear 26 is a key groove 25a formed on the drive shaft 25.
It is supported by the adjusting block 4a of the chain conveyor 6 so as to be slidable along the chain conveyor 6 in accordance with the width of the film. The drive shaft 25 includes a chain 25b, bevel gears 25c, 25d, and a chain 25.
e, the motor via a transmission mechanism such as a reducer 25f.
The driving force of _M2 is transmitted.

Even when the chain conveyor 6 is moved by the mechanism described above, the driving force of the drive shaft 25 is transmitted to the sprocket 6a via the gears 26 and 24.

By transmitting the driving force of the motor _M1 to the drive shaft 25 via an electromagnetic clutch instead of the motor _M2 , the chain conveyor 6 can be driven independently of the vertical movement of the elevator head 13. I can do it. By doing so, the driving source can be used also.

Front feed devices 60, 60' are provided near the inner sides of the chain conveyors 6, 6' on the supply side via mounting fittings 59, 59', respectively. Note that the front feeding devices 60 and 60' have a substantially symmetrical structure, and the front feeding device 60 will be explained.

The forward feeding device 60 feeds out the film forward to a position where the film is held between the clip 7 of the chain conveyor 6 and the rubber belt 6a, and includes upper and lower feeding belts 27 and 28. As shown in FIG. 10, three sets of lower feed-out belts 28 are arranged at predetermined intervals, with two adjacent belts forming one set. Upper feeding belt 27
A total of three belts are disposed so as to abut on the center recess of each pair of feed belts 28, 28.

As shown in FIG.
are stretched between pulleys 27a and 27b of the same diameter, and the lower feeding belt 28 is connected to a large diameter roller 28.
a and the small diameter roller 28b.

The front large-diameter roller 28a has a drive shaft 6 with a hexagonal cross section.
1, and the drive shaft 61 has a first
As shown in the figure, the driving force of a motor (not shown) is transmitted through a chain 62.

As shown in FIG. 2, the large diameter roller 28a is connected to the film support roller 20' via a belt 30, and rotates the support roller 20'. Further, the support rollers 21' are also linked via a belt (not shown) so that they rotate in synchronization.

The support rollers 20', 21' are made of metal such as aluminum with good conductivity, and at least their surfaces are grounded. Stretch film is highly insulating and thin, and is also highly susceptible to charging due to friction as it is pulled from the film roll. This is because if this charging is not prevented or regulated, the ICs, LSIs, etc. that make up the control circuit may malfunction due to the effects of electrostatic noise. If it is insufficient to ground only one side of the stretch film, a separate grounding roller may be provided to ground both sides.

The forward feeding device 60 holds the film A' ₁ between the upper and lower feeding belts 27 and 28, and drives the lower feeding belt 28 to feed the film A' ₁ forward.

The forward feeding speed of the forward feeding device 60 is set to be slightly slower than the feeding speed of the chain conveyor 6. By doing so, the stretch film _A'1 can be pre-stretched in the Y-Y axis direction.

In FIG. 1, 29 and 29' are cutter devices, which are provided on the chain conveyors 6 and 6', respectively. Each of the cutter devices 29, 29' is provided with a sliding member having a saw blade-shaped top on the opposing side, and this sliding member is configured to be moved up and down by a driving means 29a shown in FIG. be done. When this sliding member slides upward, the film is cut.

Next, the operation of the apparatus of the embodiment will be explained.

First, select the film roll A ₁ that matches the material to be packaged from among the film rolls A 1 and A ₂ , and rotate _the handle 3c to widen the ends of the chain conveyors 6 and 6' according to the width of the film roll A _1. Adjust corners and spacing. That is, by rotating the handle 3c clockwise, the hypoid gears 1c,
Adjusting screws 1, 2 are rotated via 2c, 3a, 3b, and the distance between chain conveyors 6, 6' is widened, and by rotating counterclockwise, the distance is narrowed.

After the adjustment is completed, as shown in FIG. 2, it is fed out via a support roller 20' and an end detection roller 40, and its leading end is held between feeding belts 27, 28 and 27', 28'. Large diameter roller 28
Rotate the stretch film A′ ₁ manually.
The blade is fed forward until the tip of the blade is directly above the cutter device 29, 29'.

In the above state, the preparation is completed and the packaging machine is ready for use. The packaging process will be explained below. In the packaging machine of the embodiment, the elevator head 13
If the vertical movement of the roller is one cycle, one article is wrapped in two cycles. However, for convenience of explanation, it will be explained here that packaging of one article is completed in one cycle, but the present invention is not limited in any way in this regard.

First, an operator places an object to be packaged on the pusher conveyor 12. Whether or not an object has been placed on the pusher conveyor 12 is determined by the weighing stability signal if the pusher conveyor 12 has a built-in measuring device, or by a micro switch, etc. if a measuring device is not built into the pusher conveyor 12. The device is informed by the sensor. As a result, the pusher conveyor 12 and the belt conveyor 14 are driven, and the conveyance of the packaged items is started.

The stretch film _A'1 is then fed out and transferred in parallel with the conveyance of the article to be packaged.

The length of the stretch film required for packaging, that is, the amount of film feeding out, can be set manually in advance using a setting dial (not shown) on the operation panel, or it can be set manually using a setting dial (not shown) on the operation panel, or it can be set manually using a sensor that measures the size of the item during transport. It is determined by detecting the The film is fed out by driving feed belts 28, 28' and support rollers 20' below the chain conveyors 6, 6'.
Support roller 20' and feeding belt 27,2
Film fed out by 7', 28, 28'
A' ₁ is the end of the belt 27, 27', 28, 28' on the end of feeding, and the both ends thereof are connected to the clips 7, 7' of the chain conveyor 6, 6' and the rubber belt 6d,
6'd, and is further fed out as the chain conveyors 6, 6' move. At this time, as described above, the belts 28, 2
Since the conveyance speed of the chain conveyors 6, 6' is set to be a little faster (approximately 5%) than that of the chain conveyor 8', the film A' ₁ is fed out by the chain conveyors 6, 6', and the film A' 1 is moved in its length direction. It is pre-stretched by about 5%.

Furthermore, since the chain conveyors 6, 6' are disposed in a widening manner as described above, the material is finally pre-stretched by about 5% at its central portion as it is fed out and transferred by the chain conveyors 6, 6'. When the chain conveyors 6, 6' have finished feeding out the film _A'1 of a predetermined length, the feeding belts 28, 28' are stopped, and the cutter devices 29, 29' are driven to remove the film A'1 necessary for packaging. The cut film A″ ₁ is then transported until its center is located on the Y-Y axis of the central part of the apparatus, and then transferred to the chain conveyor 6, 6' _. drive is stopped. In this state, the film A″ ₁ is placed at the packaging position 9.
It is held in an extended position with a wrinkle-free peen in a position above the elevator head 13 on the underside of the elevator head.

After the transfer of the film _A''1 and the loading of the object to be packaged onto the elevator head 13 are completed, the elevator head 13 starts to rise.As a result, the object to be packaged pushes up the film _A''1 on the way. The upper surface is covered with the film _A''1 and reaches the packaging position 9.

At this packaging position 9, the horizontal folding plates 17,1
7' performs left and right horizontal folding. In addition,
In the process of horizontal folding, the left and right movable guide members 2
1, 21', 23, 23' are driven, and the right and left sides of the film _A''1 are moved by the clips 7, 7' and rubber belts 6d, 6'd that engage with these guide members 21, 21', 23, 23'. The clamp is released.

Immediately before or after the end of the left and right folding, front folding is performed by the front folding plate 16. In this pre-folding process, the central movable guide member 22' of the chain conveyor 6' on the front side 10b is driven,
The clip 7' that engages with the guide member 22' and the rubber belt 6'd release the front central part of the film A" ₁ . After the front folding is completed, the pusher 3
1, the article to be packaged is carried out onto the heat belt 19, and during this carrying out, the rear folding roller 1
Post-folding is performed by 8. Then, during this post-folding process, the central guide member 22 of the rear chain conveyor 6 is driven, and this guide member 22
The rear central part of the film _A''1 is released from being held by the clip 7 that engages with the rubber belt 6d. When the transfer onto the heat belt 19 is completed, the above-mentioned post-folding is completed and the packaging is completed. After the packaging is completed, the folded portion at the bottom of the packaged item is thermally welded while being transferred by the heat belt 19, and the packaging is completed.
After the above-mentioned front folding is completed, the elevator head 13 starts to descend, and the elevator head 13 returns to the lower position and the heat belt 1 of the packaged object
9, the device enters a standby state. Incidentally, if the next item to be packaged has already been placed on the pusher conveyor 12 during the above packaging process, the above operation can be repeated.

As described above, in the embodiment, the front feeding device 6
0,60' feeding belt 27, 28, 27', 2
8' constitutes the first feeding device of the present invention to feed the film A' ₁ from the film roll A ₁ ;
The chain conveyors 6 and 6' constitute the second feeding device of the present invention, and stretch the film A' ₁ in the transfer direction and the width direction during feeding, and when the feeding and transfer direction is completed, the stretching in both directions is completed. state.

Incidentally, in place of the above embodiment, the roller 40 is used in the present invention.
The roll is turned into a film roll by applying rotational power to
The first feeding device pulls out the film from A ₁ , and feeding belts 27, 28, 27', 2
8' and chain conveyors 6, 6' constitute a second feeding device, and the transfer speed is adjusted between the feeding belts 27, 28, 27', 28' of the second feeding device and the rollers 40 of the first feeding device. It is also possible to provide a difference so that the film is stretched in the transport direction.

Further, the second feeding device is not limited to a structure in which the film is held and transferred by a clip, but may be a structure in which, for example, a rubber belt or the like is used to hold and transfer the film.

Further, in the above embodiment, when the interval between the film feeding and transferring devices 6, 6' is adjusted according to the width of the film to be used, by changing the divergence angle corresponding to the interval, films of different widths can be processed. We have devised a way to ensure that the degree of expansion is approximately the same even when using This is because the width of the film used differs significantly (for example, the film above
A ₁ width is 200mm, film roll A ₂ width is 400mm)
Although this is because the above points are taken into consideration, the configuration is not limited to this configuration due to the above-mentioned reasons. For example, if the divergence angle can be kept constant even when the distance is changed, the distance adjustment mechanism of the film feeding and transferring device can have a relatively simple structure.

The structure of the film feed-out and transfer device is not limited to the above-described embodiment, but may be of any type as long as it feeds out and transfers the film by holding the ends of the film.

[Brief explanation of the drawing]

Figure 1 is a plan view showing the structure of the main parts of a stretch film packaging machine embodying the present invention, Figure 2 is a vertical cross-sectional side view of the same, and Figures 3 to 5 are stretch film packaging machines embodying the present invention. A drawing showing the outline of the machine.
3 is a vertical side view, FIG. 4 is a sectional view of the same, FIG. 5 is a front view of the same, FIG. 6 is a plan view showing the structure of the film front feeding device, and FIGS. 7 to 10 are FIG. 7 is a top view of the main parts, FIG. 8 is a top view, FIG. 9 is a side view, and FIG. 10 is a front view.
FIG. 11 is a side view of essential parts showing the structure of the movable guide member. In the figure, 1 and 2 are adjast screws, 6 and 6'
is a chain conveyor, 6d and 6'd are rubber belts,
7, 7' are clips, 21, 21', 22, 22',
23 and 23' are movable guide members, and A ₁ and A ₂ are stretch film rolls.

Claims (1)

[Scope of utility model registration request] A first feeding device that draws out and transfers the film from a film supply source and a second feeding device that feeds out and transfers the film while holding the side edges of the film fed out from the device are disposed along the film transfer path. The second feeding device is composed of a pair of left and right conveyors, and both conveyors are arranged in a divergent shape with respect to the direction in which the film travels, and the transfer speed is set higher than that of the first feeding device. A film feeding device in a film packaging machine.