JPH0120246Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Field of Industrial Application) The present invention relates to a film feeding and transferring device for a stretch film packaging machine, and more specifically, to a device that feeds and transfers a film by holding both ends of the film at a plurality of points. .

(Prior art and its technical issues) As a film feeding device in a conventional stretch film packaging machine, rubber belts are disposed above and below both sides of the film transport path, and the upper and lower rubber belts cover each side edge of the film. There is a device that feeds out and transfers the film by holding it in place. Since this device has a weak force for clamping the film side edges, there was a problem in that the rubber belt had to be pressed by a pressing device separate from the feeding and transporting device to prevent the film from coming off during packaging.

Furthermore, Japanese Patent Application Laid-Open No. 57-68309 is known as another prior art.

In this conventional device, both ends of the film are held between a pair of upper and lower clip members, and the film is fed out and transferred by moving the clip members together with an endless chain. This makes it possible to firmly hold the film, compared to a device that feeds and transports the film by sandwiching it between rubber belts. For this reason, when the object to be packaged is raised by the elevator of the packaging machine and the center of the stretch film is pushed up to cover the top surface of the object to be packaged, the end of the film can be held only by being held by the clips. , there are the following problems.

That is, since the clip member is composed of an upper part 11 and a lower part 12 each having a clamp 13, 13, a large number of parts are used, the mounting structure is complicated, and the contact surfaces of the clamps 13, 13 are flat. Therefore, it is necessary to attach an elastic pad to the inner surface of each clip, which makes the processing of the clips very troublesome. Requires a certain amount of pressing force.

Therefore, it is suitable for a stretch film packaging machine in which each part is operated by compressed air from an air compressor, but is difficult to adopt in a stretch film packaging machine using an electric motor.

Furthermore, Japanese Utility Model Publication No. 55-50097 is known as a prior art.

This conventional device has a structure in which a rubber plate 11 is provided on the lower member of the clip member, but the need for a base 1 on which the rubber plate is attached was disclosed in the above-mentioned Japanese Patent Application Laid-Open No.
This is similar to 68309, and as a result, the aforementioned problem of complicating the structure cannot be resolved, and no improvements have been made to the joint surfaces of the upper and lower clips to increase the clamping force.

The present invention was devised in view of the above-mentioned conventional circumstances, and its purpose is to provide a strainer that has a relatively simple structure and can provide sufficient film retention force even with a small pressing force, even though a clip is used. An object of the present invention is to provide a film feeding and transporting device for film.

(Technical Means for Solving the Problems) The film feeding and transferring device of the present invention has a pair of endless chains rotatably disposed on both sides of the film transferring path, and each chain has a round cross section on the outer periphery. Each chain is provided with endless elastic belts around each chain, and a plurality of clips having recesses that fit into the elastic belts are swingably provided on the side surfaces of each chain, and between the clips and the belts, The film is fed out and transferred by driving the chain while holding both ends of the film, and a guide member for opening and closing the clip is provided at a predetermined position near the chain.

(Function) According to the present invention, the clip moves in an open state as the chain is driven, and when the clip is closed by the guide member, the side edge of the film is held between the clip and the elastic belt. The film is fed out and transported in that state.

The film is held securely by fitting the concave portion of the clip into the elastic belt having a round cross section, so that the film side end is curved along the shape of the belt.

(effect) According to the present invention, the following effects can be obtained.

The end of the film is clamped by the fit between the recess of the clip and the elastic belt with a round cross section.
The contact area between the clip and the elastic belt is increased, and the end portion of the film is held in a curved shape, so that a sufficient film holding force can be obtained with a small pressing force.

Furthermore, since the pair of one side members has a simple structure in which an elastic belt is provided around the chain, the number of clips can be reduced to about half compared to the case where conventional upper and lower clips are used. This simplifies the configuration, reduces the number of parts, and improves assembly workability.

Since the film side end portion is held on the elastic belt provided around the outer periphery of the chain, the spacing between the chain conveyors can be narrower than in conventional conveyors. Coupled with the above effects, the device can be downsized.

By using an endless belt made of elastic material, there is no need to attach elastic parts to the inner surface of the clip as in the past, which simplifies the processing of the clip, and reduces the film's holding power by preventing the parts from peeling off. This eliminates the risk of a decrease in performance.

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

FIG. 8 is a longitudinal sectional side view of the stretch film wrapping machine according to the embodiment, and 10 in the figure indicates the frame of the stretch film wrapping machine. This machine frame 10 is shown in Figure 6~
As shown in FIG. 10, it has a substantially rectangular parallelepiped configuration, with the left side in FIG. 8 being the front side 10b and the right side being the back side 10b.
Let it be c.

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. 7, 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. 7 and 8) 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 approximately at 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. It is set to the position where .

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.

Moreover, the reason why the carry-in conveyor 11 is configured by combining both the pusher conveyor 12 or the belt conveyor 14, instead of using only one of the pusher conveyor 12 and the belt conveyor 14, is that when assembling and manufacturing the packaging machine, the packaging machine can be easily packaged by simply rearranging the same parts. This product can be manufactured in a packaging machine in which the direction of conveyance of the finished product is not the backward direction (in the case of the example) but the forward direction. is detailed in.

The elevator head 13 and head mounting base 1
3b is formed into a slit shape as shown in FIGS. 6 and 7, 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. 7, and the small block 13d receives a force from below in FIG.
The small blocks 13e are configured to be tilted by a force from the left side in FIG. 7, so that the stretch film folding operation, which will be described later, can be carried out without any hindrance.

In addition, 15 in FIG. 8 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 transverse folding plates 17, 17', a front folding plate 16 and a rear folding roller 18 are provided, which form an opening through which the package pushed up by the elevator head 13 is passed.

The horizontal folding plates 17, 17' are used for horizontal folding in the left and right direction, and are each provided so as to be slidable in the vertical direction in FIG. 7, and are configured to slide in conjunction with each other in opposite directions.

The front folding plate 16 performs forward folding after the horizontal folding is completed, and is provided so as to be slidable in the left-right direction in FIG. 7, and is driven independently of the horizontal folding plates 17 and 17'. An unloading pusher 31 is disposed above the front folding plate 16.

The carry-out pusher 31 transfers the packaged items that have been prefolded and horizontally folded to the rear folding roller 18.
During this movement process, the post-folding roller 18 performs post-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. 6 shows the 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 then passes through the end detection roller 40 up and down. is inserted between the feeding belts 27, 27', 28, 28'. The belts 27, 27', 28, 28' constitute a film advance device 60, 60' (FIG. 4).

Next, to briefly explain the feeding and transport of the stretch film _A'1 , the belts 27, 27', 2
The film inserted between 8 and 28' is
7, 27', 28, 28' are fed out by the rotational action. The film _A'1 that has been fed out to the front end of the belts 27, 27', 28, and 28' (the left side in FIG.
The film A'1 is held between the rubber belts 6d and 6'd and fed out to a length necessary for packaging, and the cutter device 29 cuts the film _A'1 to the required length. The cut film A" ₁ is transferred to a predetermined position above the elevator head 13, that is, until the center of the film A" ₁ coincides with the center of the elevator head 3, and then stopped and placed in a standby state.

A film feeding device consisting of clip groups 7, 7' and rubber belts 6d, 6'd is shown in FIGS. 6 and 9.
Packaging position 9 and elevator head 1 as shown
7 and 10 at the height between the lower end position of 3.
As shown in the figure, they are disposed 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. 9 and 10.

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.

Also, along the back surface 10c of the machine frame 10, the rotating shaft 3
is arranged on the shaft 3, and the hypoid gear 1 is connected to the shaft 3.
Hypoid gears 3a and 3b meshing with gears c and 2c are fixed, respectively.

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 portions 2a and 2b, respectively, and the threaded portions 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, the packaged item is carried out in the opposite direction to the carrying direction to complete the packaging. This is because drastic changes in the color of the skin cause twitching and wrinkles, which is undesirable. Further, the threaded portions 1a and 1b have a generally coarser pitch than the threaded portions 2a and 2b.

In the figure, D is the distance between the centers of the packaging position 9, and d
is the distance on the adjusting screw 2 side, and C is the stretching rate of the film (hereinafter referred to as the pre-stretch degree), then the pre-stretch degree C at the center of the packaging position 9 is C=D-d/d. It is. In order to keep this pre-stretch 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 pitch of 2b is set to satisfy these requirements.

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, the axis passing through the center of the elevator head 13 in the horizontal direction is the X-X' axis, and the axis passing through the vertical direction is the Y-axis.
If the Y' axis is the chain conveyor 6, 6', then the X-
It is disposed in a diverging shape with respect to the film transport direction with respect to the X' axis. 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. 9, a mounting support member 50 is rotatably provided on the adjusting block 4a, and its range of rotation is regulated by an engaging pin 51. As shown in FIG. The adjusting block 5a has a mounting support 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. Chain 6c as shown in detail in FIGS.
A plurality of substantially U-shaped mounting plates 7a, 7a, . . . are provided at predetermined intervals on the side surface of the rear surface 10c.

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 is molded from a molding material such as ABS resin, and has a screw-like configuration that swings around a mounting portion 7e provided at its center. A semicircular recess 7d that fits into the rubber belt 6d is formed on the rubber belt 6d side of the clip 7, and
The other end acts as an operating piece 7f when opening and closing the clip 7.

As shown in FIG. 5, a support plate 55 is attached to the upper part of the mounting board 54 over a predetermined area by screws 56, and a protrusion 55a integrally formed on this support plate 55 is connected to a chain. 6c to guide and support it, 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. Note that the state in which the clip 7 and the rubber belt 6d are in contact with each other as shown by the solid line in FIG.
The state in which d and d are separated is called an 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 by balance in a substantially closed state 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. 2, 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. 10, three movable guide members 21, 22, and 23 on the left side, center, and right side are arranged near the outside of the chain conveyor 6. Each movable guide member 21, 22, 23 has a substantially similar structure,
The central movable guide member 22 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, such as springs, disposed below near both ends thereof, and is constantly biased upward.

As shown in FIG. 5, the lower pressing plate 22b is formed into a U-shape in cross section, and this side surface is formed by the pin 22e.
is connected to the tip of the operating rod 22f of the solenoid S. 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, 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 7d of the clip 7
is fitted with the rubber belt 6a to firmly hold the side edge of the film _A'1 .

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. 5, and the upper pressing plate 22a moves downward.
The operating piece 7f in the space 22c is pushed by the upper pressing plate 22a and moves downward, and the clip 7 is opened.

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

As shown in FIGS. 9 and 10, a gear 24 is coaxially fixed to the sprocket 6a on the opposite side from the film supply section, and an adjusting screw 1
A drive shaft 25 is disposed parallel to the drive shaft 25, and 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 driving force of the motor M ₂ is transmitted to the drive shaft 25 via transmission mechanisms such as a chain 25b, bevel gears 25c and 25d, a chain 25e, and a speed reducer 25f.

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 fittings 59, 59', respectively. Note that the forward feeding devices 60 and 60' have a substantially symmetrical structure, and the forward 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.
is 3 at a predetermined interval, with two adjacent ones as one set.
A group is arranged. A total of three upper feeding belts 27 are arranged so as to contact the central recesses of the respective sets of feeding belts 28, 28.

As shown in FIG. 9, the upper feeding belt 27 is stretched between pulleys 27a and 27b of the same diameter.
The lower delivery belt 28 is stretched between a large diameter roller 28a and a 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 FIG. 0, it is linked to a motor (not shown) via a chain 62.

As shown in FIG. 9, 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 connected to each other 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, there is a risk that 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 pre-feeding speed of the pre-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. 10, 29 and 29' are cutter devices,
The chain conveyors 6 and 6' are respectively provided. 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.
It is held between 7' and 28'. The large-diameter roller 28a is manually rotated to advance the stretch film _A'1 until its leading end is directly above the cutter devices 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 the 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 4 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 the length of the stretch film required for packaging can be set manually using a setting dial (not shown) on the operation panel, or the length of the stretch film required for packaging can be set manually in advance using a setting dial (not shown) on the operation panel, or the length of the stretch film required for packaging can be set manually in advance using a setting dial (not shown) on the operation panel, or the length of the stretch film required for packaging can be set manually in advance using a setting dial (not shown) on the operation panel, or the length of the stretch film required for packaging can be set manually in advance using a setting dial (not shown) on the operation panel. Determined by detection with a sensor. 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,
6d, and is further fed out as the chain conveyors 6, 6' move. At this time, as described above, the belts 28, 2
Since the transfer speed of the chain conveyors 6, 6' is set to be a little faster (approximately 5%) than that of the film A' 1, the length of the film A' ₁ is It is pre-stretched by about 5% in the direction.

Further, 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' finish feeding out the film _A'1 of a predetermined length, the driving of the feeding belts 28, 28' is stopped, and
The cutter devices 29, 29' are driven to cut the film _A''1 of the length required for packaging.The cut film _A''1 is then positioned with its center on the Y-Y axis in the middle of the device. After the chain conveyors 6, 6' are transferred, the driving of the chain conveyors 6, 6' 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 clamping is released. Immediately before or immediately after the left and right folding is completed, the front folding is performed by the front folding plate 16.

In this pre-folding process, the central movable guide member 2 of the chain conveyor 6' on the front side 10b
2' is driven, and the film is held by the clip 7' and the rubber belt 6'd which engage with this guide member 22'.
The front central part of A" ₁ is released. After the front folding is completed, the pusher 31 carries out the packaged item onto the heat belt 19, and during this carrying out, the rear folding roller 18 performs the rear folding. Then, in the process of folding, the central guide member 22 of the chain conveyor 6 on the rear side is driven, and the clip 7 and the rubber belt 6 that engage with this guide member 22 are driven.
The rear center portion of the film A″ ₁ is released from being held by d. Upon completion of carrying out onto the heat belt 19, the above-mentioned post-folding is completed and packaging is completed.After packaging is completed, the packaged items are During transport by the heat belt 19, the folded portion at the bottom is thermally welded to complete the packaging.After the above-mentioned pre-folding is completed, the elevator head 13 starts to descend, and the elevator head 1
After returning to the lower position 3 and completing carrying out the packaged object onto the heat belt 19, the apparatus enters a standby state. Note that during the above packaging process, if the next item to be packaged has already been placed on the pusher conveyor 12, the above operations are repeated.

As mentioned above, the film A″ ₁ has both ends attached to the clips 7, 7′ and the rubber belt 6d, respectively.
6'd and fed out and transferred. In this case, in particular, rubber belts 6d and 6'd having a circular cross section are used, and recesses 7d and 7d' are formed on the inner surfaces of the clips 7 and 7', respectively, to fit and accommodate the rubber belts 6d and 6'd. , film
The end of A″ ₁ can be held more strongly.

In the above-described embodiment, the film is held between the fixed guide members 8a and 8b'.
Movable guide member 2 operated by a solenoid
1, 21', 22, 22', 23, and 23' are configured to release the film from being held, but the structure of the guide member is not limited to this.

In short, any structure may be used as long as it has the function of holding or releasing the film at a predetermined position or at a predetermined time.

[Brief explanation of the drawing]

FIG. 1 is a plan view showing the main parts of a film feeding and transferring device embodying the present invention, FIG. 2 is a front view of the same,
Fig. 3 is a right side view of the same, Fig. 4 is a side view of main parts of a stretch film packaging machine using the embodiment device,
Fig. 5 is an enlarged vertical sectional view of the main parts, Fig. 6 is a vertical sectional front view showing an outline of the packaging machine, Fig. 7 is a longitudinal sectional plan view, Fig. 8 is a vertical sectional side view, and Fig. 9 is a main part of the packaging machine. FIG. 10 is a longitudinal sectional side view showing the entire film feeding and transferring device according to the invention, FIG. 10 is a plan view thereof, and FIG. 11 is a plan view showing the structure of a movable guide member. In the figure, 6, 6' are chain conveyors, 6c, 6
c' is a chain, 6d, 6'd are rubber belts, 7,
7' is a clip, 8, 8' are fixed guide members, 2
1, 21', 22, 22', 23, 23' indicate movable guide members.

Claims (1)

[Scope of utility model registration request] A pair of endless chains are rotatably arranged on both sides of the film transfer path, and an endless elastic belt with a round cross section is provided around the outer periphery of each chain. A plurality of clips having recesses that fit into an elastic belt are swingably provided, and the chain is driven with both ends of the film being held between the clips and the belt to feed and transport the film. A film feeding and transferring device for a stretch film packaging machine, characterized in that a guide member for opening and closing the clip is provided at a predetermined position near the chain.