JP3473430B2 - 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 stretch wrapping machine for wrapping products such as perishable foods using a stretched film, and more specifically, unwinding the film from a film roll set in a film roll arranging section, The film is transferred to a pair of film feed mechanisms via the film holding unit, and the film feed mechanism feeds the film while sandwiching both side edges in the width direction and supplies the film to the packaging section. The packaging section clamps both side edges. To a stretch wrapping machine that pushes up and wraps products by an elevator toward a flat film.

[0002]

2. Description of the Related Art In a conventional stretch wrapping machine, a plurality of types of film rolls are set in a film roll arranging portion, and an automatic changer is operated to automatically change the film rolls according to the size of the product to be wrapped. There is a method to do. In this packaging machine, the data (type) of the film roll is set in advance by inputting or the like. In other conventional packaging machines, only one film roll is set in the film roll placement section, and the position of the fixed guide, which is different depending on the width of the film roll set in this placement section, is detected and the film feed is detected. There is also a system in which the position of the mechanism is automatically adjusted (JP-A-6-72406).
No.). Therefore, in any of the above conventional packaging machines, the initial position of the film feed mechanism is inevitably changed with the exchange operation of the film rolls, and the changing operation is not forgotten.

As another conventional packaging machine, there is a system in which a plurality of types (for example, two types) of film rolls are set in the film roll arranging section and the film to be used is manually changed according to the product to be packaged. Even in this conventional packaging machine, when the film is replaced,
It is necessary to change the initial position of the film feed mechanism according to the width of the film used, in order is previously set a plurality of films, it is difficult to adopt the method using a fixed guide described above Or, even if it is adopted, the structure becomes complicated because it requires detection means for the number of film rolls. However, manually changing the position of the film feed mechanism is very time-consuming and troublesome, and if the change operation is forgotten or mistaken, the film feeding error, poorly finished packaging error, and poor workability will occur. There is a problem that causes such as.

[0004]

In view of the above conventional circumstances, the present invention is used in a stretch wrapping machine in which a plurality of types of film rolls are set in a film roll arranging section and the films to be used are replaced manually. An object of the present invention is to provide a packaging machine in which the initial position of the film feed mechanism is automatically changed according to the film. It is another object of the present invention to provide a film width detecting means that can detect the width of a film to be used by using a simple structure.

[0005]

According to the present invention, in the above stretch wrapping machine, that is, while setting plural kinds of film rolls in the film roll arranging section,
The film to be used can be replaced by manual operation, and the film holding part holding the film can be fed to the film feed.
In the stretch wrapping machine, the film holding unit transfers the film to a pair of film feeding mechanisms by moving it toward the mechanism, and the film feeding mechanism feeds the film to both sides of the film in the width direction while sandwiching the film feeding mechanism. At the tip of the
And mouth, are arranged corresponding to the opening, and the film width detecting means for detecting the width of the film held by the film holding portion, detection based on a detection result of said detecting means
And a control means for setting the initial position of the film feed mechanism to a position corresponding to the opened opening portion (claim 1). According to the first aspect, the width of the film held by the film holding unit, that is, the type of the film used is directly detected. Therefore, even if a plurality of film rolls are set in the film arrangement unit, there is no problem. The width can be detected, and the initial position of the film feed mechanism is automatically set by the control means according to the detection result.

In view of the relationship between the film holding section and the film transfer means by the film feed mechanism, a specific arrangement of the film width detection means will be described.
Each upstream of the film feed mechanism openably configured for clamping the leading end of the film held by the film holding portion, before Symbol film width detection result is selected based on the opening of the detection means It is characterized in that the opening and closing portion of the film feed mechanism sandwiches the film side end portion. According to this aspect, not only the film passing means from the film holding portion to the film feeding mechanism has a simple structure, but also the opening portion of the film holding portion, that is, the film feeding mechanism is set by the detecting means. The film width corresponding to the position to be surely detected. The arrangement structure and type of the film width detection means are not particularly limited, but in a preferred embodiment, the detection means is arranged on the opposite surface of the film transfer path from the film roll arrangement portion to the film holding portion. A plurality of reflection type optical sensors (claim 3). As a result, the edge portion of the film stretched over the film transfer path is searched by the reflective optical sensor to detect the film width, and the detection means can be made compact and have a simple arrangement structure.

A preferred embodiment of the film feed mechanism is that it is applied to a packaging machine that performs a pre-stretching operation, that is, the film feed mechanism is configured so that its interval can be expanded, and the product to be packaged by expanding the interval. Pre-stretching for stretching the film in the width direction according to the size is performed, and the amount of the pre-stretch is determined based on the size of the product and the detection result of the detection means (claim 4). That is, the film width detected by the detecting means is taken in and used as data for determining the amount of pre-stretch. Further, as an example of a specific mode of the film feed mechanism, the film feed mechanism on each side is composed of a conveyor belt consisting of a pair of upper and lower belts and a transfer belt, and is divided into a lower belt of the pair of conveyor belts. -Shaped film clamp is arranged, and a pad plate is arranged on the upper belt.When the film is transferred, the film clamp is attached in the direction of pressing the belt so as to clamp the film end between the upper and lower belts. When being biased, the transfer belt constitutes the opening / closing portion of the film feed mechanism (claim 5).

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of the present invention will be described with reference to the drawings. FIGS. 1 to 3 schematically show a stretch wrapping machine. In the figure, a belt conveyor 1 that conveys a product a to an elevator 2 provided inside the machine frame A is provided on the front side of the machine frame A, a packaging section b is provided above the elevator 2, and the packaging section b is provided. Of the film roll arranging section 3 and a film holding section for holding the leading end of the film 4'unrolled from the film roll 4a or 4b set in the arranging section 3 to the side (direction intersecting at right angles with the conveyor). 5 is disposed, and a film feed mechanism 6 that conveys the film 4 ′ held by the film holding section 5 to the pull-out packaging section b with both ends sandwiched is disposed so as to face the film holding section 5. Above the film feed mechanism 6, the left and right folding plates 7 and 7'for folding the end of the film 4'covering the upper surface of the product a to the bottom side of the product a, the front folding plate 8, and the front folding plate 8 are provided. A discharge pusher 10 for arranging and carrying out a packaged product is disposed, and the rear folding rod 8'abutting the rear end of the film abuts when the pusher 10 discharges the film so that the film can be folded back. Further, a cutting device 11 is arranged between the film holding section 5 and the film feed mechanism 6 to cut the film held by the film feed mechanism 6 and pulled out into a predetermined length.

The belt conveyor 1 is constructed by partially overlapping a first conveyor 101 and a second conveyor 102 in which a plurality of belt-like belts are arranged in parallel at a predetermined interval. The second conveyors 102 are driven by separate motors (not shown). And product a
A second conveyor 102, which is loaded one by one from a centering device (not shown) arranged in the preceding stage, has a transport speed higher than that of the first conveyor 101, and transports the product a onto the elevator 2. A plurality (four in the drawing) of stoppers 103 for receiving the front end portion of the product a conveyed by the second conveyor 102 are fixed on the belt surface of the one conveyor 101 at equal intervals. As a result, the product a
Stopper 10 is used to position the carriage on the elevator head.
It is performed on the basis of the front end with which the front end of the product a is brought into contact with item 3.
In addition, the first conveyor 10 that conveys the product a onto the elevator 2
The terminal side of 1 in the transport direction is inserted and arranged between a plurality of divided elevator heads constituting the elevator 2, and the transport surface of the first conveyor 101 is above the surface of the elevator head before rising and the second conveyor. The transport surface of 102 is located above the transport surface of the first conveyor 101. Further, a first conveyor 101 that constitutes the belt conveyor 1
The product a conveyed by the drive of the belt conveyor 1 is located in the middle of the overlapped area between the second conveyor 102 and the second conveyor 102.
The light projector 12a and the light receiver 12b of the height and depth detection sensor 12 for detecting the height and the length (depth dimension) of the sensor are arranged to face each other across the transport path. The motor for driving the first conveyor 101 and the motor for driving the second conveyor 102 are simultaneously turned on.
It is controlled so that it is turned off / on and operates for the same period.

In the film arranging portion 3, a plurality of film rolls 4a and 4b of different types (widths) (two are illustrated in the embodiment) are detachably attached to the support shafts 13a and 13b. The operator selects one of the film rolls 4a or 4b and pulls out and mounts it on the film holding portion via the tension roller 14a and the guide rollers 14b and 14c. That is, the film rolls 4a or 4b of the film arranging unit 3 are exchangeably supplied to the film holding unit 5, and the exchange operation is performed manually by an operator.

The film holding section 5 pulls out and holds the film 4'from the film roll 4a or 4b set in the film arranging section 3 and transfers the leading end of the film 4'to the film feed mechanism 6. The film holding unit 5 includes a lower holding plate 502 attached to an endless belt 501 arranged in parallel with a space equal to or larger than the maximum width of the film roll 4a or 4b set in the film roll arrangement unit 3, and a lower holding plate 502. An upper holding plate 503 that holds the film 4'supported on the surface of the holding plate 502 with the lower holding plate 502 with a slight gap, a holding roller 504 attached to the lower holding plate 502, and a film holding unit 5 It is composed of a moving means 505 for moving the film toward the film feed mechanism 6 and a feeding roller 506. The film 4'of the film roll 4a or 4b of the film roll placement unit 3
The front end is supplied to the film holding unit 5 via the feeding roller 506, and the film holding unit 5 is on the transport surface line (moving line) of the film 4 ′ in the film feed mechanism 6 described later, and on the moving means 505. It is installed so as to move horizontally between the feeding roller 506 and the film feed mechanism 6 by driving. Then, the lower holding plate 502 and the upper holding plate 503 are provided with notched openings T0 and T1, T2, and T2 on the front end side facing the film feed mechanism 6, respectively.
T3 and T4 are formed so that the film 4'can be delivered to the film feed mechanism 6 described later (see FIGS. 3 and 4).

A film width detector 15 is fixedly installed between the film roll arranging section 3 and the film holding section 5, more specifically, on the front surface or the back surface facing the film transfer path between the both sections (see FIG. 2). . The film width detector 15 includes a plurality of film width sensors S1, S2, S3, S4 (four in the drawing are illustrated).
The respective sensors are arranged at positions corresponding to the openings T1, T2, T3, T4 formed in the lower holding plate 502 and the upper holding plate 503 of the film holding unit 5 (FIGS. 3, 4). reference). Thereby, the film width is detected by determining whether or not the film 4'is present on the facing surface of each of the sensors S1, S2, S3, S4. Specifically, each sensor S1, S2, S3, S4 shows a case where a reflection type optical sensor is used from the light emitting element 16 and the light receiving element 17 (see FIG. 2), and the irradiation surface of the light emitting element 16 is shown. If there is a film 4 ', turn it on when the light receiving element 17 receives the reflected light,
If there is no film 4 ', it is set to OFF. That is, the film width is determined by setting one end side of the film 4'to a predetermined position and detecting the other end position by the detector 15.

The film feed mechanism 6 is arranged on the line of the opening T0 located on the reference side of the film 4'notched in the lower holding plate 502 and the upper holding plate 503 of the film holding section 5 described above. 6B and a front side feed mechanism 6A arranged on any one of the openings T1, T2, T3, T4 located on the opposite side in the width direction of the film 4 ', and these feed mechanisms are constituted by the packaging portion b. Are arranged in parallel with the film sandwiched therebetween and are supported so as to be movable in the width direction of the film. The front side feed mechanism 6A and the rear side feed mechanism 6B have a pair of upper and lower endless elastic belts 602 and 602 which sandwich the widthwise side end of the film 4 ', and the forward side of the lower elastic belt 602 to the upper side. (5 in the drawing) divided clamp plates 603 that are pressed against the outward path of the elastic belt 601
And a backing plate 604 inserted between the forward side and the backward side of the upper elastic belt 601. These components are supported by attachment frames 605 and 605 'which are movable in the width direction of the film. . The pair of upper and lower endless elastic belts 601 and 602 of the front feed mechanism 6A and the rear feed mechanism 6B are provided.
The upper and lower belts 60 by the film feed motor 6C
The film 4 ′ sandwiched between 1 and 602 is rotated in the direction of pulling out.

The movable mounting frames 605, 605 'are slidably connected to two guide rods 606, 606' arranged at right angles under the mounting frames 605, 605 '.
The belt 60 is supported via 7, 607, 607 ', 607', and the connecting members 607, 607, 607 ', 607' are endlessly rotatable belts 60.
8a, 608b, 608c, 608d are connected and fixed, and their respective belts
608a, 608b, 608c, 608d are independent motors 609a, 609b,
It is configured to be driven by 609c and 609d. That is, the front feed mechanism 6A is driven by the belts 608a and 608b, and the rear feed mechanism 6B is driven by the belts 608c and 608d. The belt 608a of the front feed mechanism 6A is driven by the first motor 609a, the belt 608b is driven by the second motor 609b, and the belt 608c of the rear feed mechanism 6B is driven by the first motor 60.
9c, the belt 608d is driven by the second motor 609d, and the front side feed mechanism 6A and the rear side feed mechanism 6B are configured to be movable in parallel, and the width of the film 4'is set in accordance with the size (depth size) of the product a. It is designed to be pre-stretched. The front end of the film feed mechanism 6A and the rear feed mechanism 6B constituting the film feed mechanism 6 are provided with a leading end of the film 4'held by the film holding portion 5 by the movement of the film holding portion. A transfer belt 6'which is drawn into the feed mechanism 6 is formed continuously so that the front end side can be opened and closed.

Since the front feed mechanism 6A and the rear feed mechanism 6B are driven by independent drive systems, respectively, the drive system (first motor 609a, second motor 609b) of the front feed mechanism 6A and the rear feed mechanism are driven. By separately controlling the drive system of 6B (the first motor 609c, the second motor 609d), the pre-stretch amount in the width direction of the film 4'and the pre-stretch loosening amount at the time of packaging, the film 4'in the width direction The movement speed when pre-stretching and loosening the pre-stretch during packaging, the timing of the movement start when pre-stretching the film 4'in the width direction and when loosening the pre-stretch during packaging, Can be different.

FIG. 5 shows an example of a control section for controlling the operation of the above-mentioned packaging machine by a microcomputer. In the figure, 24 is a CPU (central processing unit) composed of a microcomputer.
The PU 24 is connected to the ROM 26, the RAM 27, the operation unit via the bus 25.
28, the display unit 29, and the I / O port 30 are connected.
The ROM 26 stores a control program executed by the CPU 24 and various tables. The RAM 27 stores various data preset for each product in advance, and data is stored when the CPU 24 executes the program of the ROM 26. It is stored temporarily. The operation unit 28 is for inputting various commands and data, and the display unit 29 is for displaying the commands and data input by the operation unit 28, the data stored in the RAM 27 or the operation status of the packaging machine, and various other items. Operation and error messages are displayed in text and graphics.

The I / O port 30 conceptually shows the entire packaging mechanism section controlled by the CPU 24. To give a portion directly related to the present invention, a drive circuit 31 for the elevator motor 2A for driving the elevator 2 is given. A drive circuit 32 for the film feed motor 6C, a drive circuit 33 for controlling the first motor 609a and a second motor 609b for moving the front feed mechanism 6A in the film width direction, and a rear feed mechanism 6B for movement in the film width direction. First motor 609c and second motor
A drive circuit 34 that controls the motor 609d is connected. Further, at the I / O port 30, a drive circuit 41 for controlling a left and right folding motor 41 'for operating the left and right folding plates 7, 7', a front folding motor 42 'for operating the front folding plate 8 and a pusher 10 are operated. A drive circuit 43 for controlling the rear folding motor 43 'is connected. Then, the control of the entire packaging machine is performed based on the count value of the timing pulse generated by the rotary encoder 2B in synchronization with the rotation of the elevator motor. The film feed motor 6
C, the first motor 609a, 609c and the second motor 609b, 609d,
The stepping motors are used as the folding motors 41 ', 42', 43 ', etc., and the rotation speed can be controlled by changing the frequency of the drive pulse, and the motor can be moved by counting the number of drive pulses. You can know the distance accurately.

Further, the I / O port 30 has a sensor K1 for detecting the width (W) of the product through the product sensor drive circuit 44,
A sensor K2 for detecting the depth (length L) and a sensor K3 for detecting the height (H) are connected, and the size data of the product is input by the detection operation of these sensors. The sensors K2 and K3 correspond to the above-described sensor 12, and the sensor K1 corresponds to a centering device that is performed during the product loading. Further, the I / O port 30 is connected with a film sensor drive circuit 45 for controlling the sensors S1, S2, S3, S4 for detecting the width of the film 4 ', which is used by the detection operation of these sensors. Film width data is entered.

Next, the working operation of the stretch wrapping machine will be described with reference to FIGS. 6 and 7. FIG. 6 is a flowchart showing an outline of the operation for setting the initial position of the film feed mechanism 6. This operation starts when the power switch of the packaging machine is turned on or when the emergency stop status is released.

In step 51, the film width detector 15 detects the width of the film 4'used in the film roll 4a or 4b. Specifically, the openings S1, S2, S3, S4 of the detector 15 are turned on / off to open the openings T1, T2, T3, T4 of the film holding unit 5.
The film width is determined by detecting the corresponding position with. That is, when only the sensor S1 is ON, the film has a width corresponding to the opening T1. When the sensors S1 and S2 are ON, the film will open at T2.
Is the width corresponding to. When the sensors S1, S2 and S3 are ON, the film has a width corresponding to the opening T3. When the sensors S1, S2, S3 and S4 are on, the film has a width corresponding to the opening T4. In step 52, the film feed mechanism 6 described above is moved to the initial position based on the detection result of step 51. Specifically, the front side feed mechanism 6A of the film feed mechanism 6 is connected to the detected opening (T
Motor 609 to a position facing (T1, T2, T3, or T4)
Move by driving a, 609c. In the drawings of the embodiments, the detection result is the above case, and the case where the front side feed mechanism 6A of the film feed mechanism 6 corresponds to the opening T1 is shown.

Therefore, even when the operator replaces and mounts the film 4'on the film holding unit 5 from another film roll 4b or another film roll which has been replaced, in order to change the film to be used, the detector 15 Thus, the width of the film is detected and the initial position of the film feed mechanism 6 is automatically changed. It should be noted that after the operation of setting the initial position of the film feed mechanism 6 is completed, the film feed mechanism 6 enters a standby state and is ready for packaging.

FIG. 7 is a flow chart showing the outline of the packaging operation after the initial position of the film feed mechanism is determined. In step 53, when the worker puts the product a on the belt conveyor 1, the conveyor 1 is driven and rotated to convey the product a to a predetermined position on the elevator 2 in the machine frame A. In step 54, the product size, that is, the width (W), the depth dimension (L) of the product a, is detected by the detection sensor 12 and the product sensors K1 to K3 such as the centering device during the transportation of the product a in step 52. Measure the height (T). In step 55, the control data necessary for the packaging operation is determined based on various data for each product stored in advance in the RAM 27 and the detected film width data and product size data.

As the control data in the above step 55, for example, the film length (cutting timing), the start timing of the front feed means 6A when prestretching the film, the prestretch amount and speed, and the start of the rear feed means 6B. Timing, pre-stretch amount and speed, start timing of front side feeding means 6A when loosening the pre-stretch amount, pre-stretch amount and speed,
These are the start timing, the pre-stretch amount, the speed, etc. of the rear feeding means 6B. In particular, the table for converting the control data based on the product size data is provided for each film width (corresponding to T1, T2, T3, T4), and the film width detector 15 described above is provided. Sensor S1,
The control data, especially the pre-stretch amount, is determined by using the conversion table of the film width detected in S2, S3 and S4. According to this, there is a case where the product size and the film width are not uniformly determined, that is, even when the product width is narrow and the control data such as the pre-stretch amount must be different even for products of the same size. It is possible to cope with that.

In step 56, the packaging work is executed based on the packaging control data determined in step 55. Specifically, the film holding section 5 is moved forward by the moving means 505 to transfer the film 4 ′ to and from the transfer belt 6 ′ of the film feed mechanism 6, and the film feed mechanism 6 moves the film 4 ′. When the film is pulled out by a predetermined length, the film is cut by the cutting device 11. The film feed mechanism 6 further conveys the cut film 4 ′, supplies the cut film 4 ′ to the wrapping portion b, performs centering, and then pre-stretches the film by a predetermined amount in the width direction. On the other hand, the product a conveyed on the elevator 2 is pushed up by the lift of the elevator 2 with respect to the film 4 ′ stretched around the packaging part b, and the end of the film covering the upper surface of the product a has a left and right folding plate. 7,
7'and the front folding plate 8 are folded on the bottom side of the product, and the discharge pusher 10 pushes the product horizontally toward the discharge part of the machine frame A to move the rear end of the film 4 '. The rear folding rod 8'folds the product a on the bottom surface thereof to complete the packaging operation.

In the above-described embodiment, since the film is used as the one side reference, based on the detection result of the film width detection sensor, only one side of the film feed mechanism 6, that is, the front position of the front feed mechanism 6A is moved. Although the setting is made, when the center reference is set, both sides of the film feed mechanism, that is, the front feed mechanism 6A and the rear feed mechanism 6B are moved. In the embodiment, the case where the pre-stretching operation is performed is disclosed.
Except for claim 4 and the claims dependent on it, the invention does not necessarily include the pre-stretching operation. Further, in the embodiment, the case where the reflection type optical sensor is used as the film width detecting means is disclosed.
Except for claim 3 and the claims subordinate thereto, the number of sensors (number of corresponding openings) is not limited to four, and the number of sensors is not limited to four.

[0026]

According to the present invention, the width of the film roll in the film roll arranging section is not detected by the fixed guide as in the conventional wrapping machine, but the width of the film loaded in the film holding section is directly detected. Therefore, even in the system in which a plurality of film rolls are set in the film arranging portion, it does not cause any trouble, and the width of the selected and used film can be detected by the detecting means. Moreover, although the film is changed manually by the operator, the operator simply attaches the film to be used to the film holding portion and the position of the film feed mechanism is automatically adjusted to correspond to the film. Since it is changed and no other operation is required, the operation at the time of film exchange is simple, and there is no risk of forgetting to change the position of the film feed mechanism or making an erroneous operation to cause an error in feeding the film or an error in packaging. Further, since the film held in the film holding section is directly detected, the film width can be detected reliably, and the structure is simple without the need for detecting means for the number of film rolls set in the film arranging section. The presence of the film in the film holding portion can be detected at the same time, and the film feeding operation can be ensured.

[0027] According to claim 2 of the present invention, it employs a simple structure, the full Irumu holder film with reliably performing film transfer to the feed mechanism a film feed mechanism to ensure the film width corresponding It is possible to provide the detecting means having a specific structure capable of detecting. According to the third aspect, a more compact and simple arrangement structure of the detecting means can be obtained. Further, according to claim 4, in the case where the packaging machine is a system for performing a pre-stretching operation, the film width detected by the detecting means is taken in and used as data for determining the amount of pre-stretching. Even when handling, the amount of pre-stretch is properly determined according to the film width used, and the packaging finish is good.

According to the fifth aspect of the present invention, there is provided a stretch packaging machine having a specific structure of the film feed mechanism and having the above-mentioned effects, which is highly effective.

[Brief description of drawings]

FIG. 1 is a vertical sectional side view showing an outline of a stretch wrapping machine according to the present invention.

FIG. 2 is a vertical sectional front view of FIG.

3 is a partially cutaway cross-sectional plan view of FIG. 1. FIG.

FIG. 4 is a perspective view of an essential part of the present invention.

FIG. 5 is an electrical configuration diagram of the present packaging machine.

FIG. 6 is a flowchart showing an outline of an operation for setting an initial position of the film feed mechanism 6.

FIG. 7 is a flowchart showing an outline of a packaging operation.

[Explanation of symbols]

a …… Product b …… Packing section 3 …… Film roll placement section 4a, 4b …… Film roll 4 ′ ……
Film 5 ...... Film holding part T1 to T4 ...... Opening part 6 ...... Film feed mechanism 6A ...... Front side feed mechanism 6B ...... Rear side feed mechanism 6 '...... Transfer belt 15 ............ Film width detector S1 ~ S4 …… Film width detection sensor 16 …… Light emitting element 17 …… Light receiving element 601 …… Upper elastic belt 602 …… Lower elastic belt 603 …… Clamp plate 604 …… Pad plate

─────────────────────────────────────────────────── --Continued from the front page (56) References JP-A-8-34415 (JP, A) JP-A-9-12008 (JP, A) JP-A-9-254933 (JP, A) JP-A-5- 333634 (JP, A) JP 56-123206 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) B65B 11/00-11/58 B65B 49/00-49/16

Claims (5)

(57) [Claims] 1. A plurality of types of film rolls are set in a film roll arranging section, a film to be used can be manually exchanged, and a film holding section holding the film is directed toward a film feed mechanism. Moved
Passing to the pair of film feed mechanism whereby, in the film by the feed mechanism to transport while pinching the both side ends in the width direction of the film stretch wrapping machine supplied to the packaging unit, the distal end portion of the film holding portion Exposing the film
A plurality of openings, a film width detection unit arranged corresponding to the openings , for detecting the width of the film held by the film holding unit, and detected based on the detection result of the detection unit . In the opening
A stretch wrapping machine comprising: a control unit that sets the initial position of the film feed mechanism to a corresponding position . Wherein each upstream of the film feed mechanism openably configured for clamping the leading end of the film held by the film holding portion, on the basis of the detection result of said film width detecting means selection The stretch wrapping machine according to claim 1, wherein the opening / closing portion of the film feed mechanism holds the film side end portion through the opened opening. 3. The stretch packaging according to claim 2, wherein the film width detecting means is a plurality of reflection type optical sensors arranged on opposite surfaces of a film transfer path from the film roll arranging portion to the film holding portion. Machine. 4. The film feed mechanism is configured such that its interval can be expanded, and by expanding the interval, pre-stretching is performed to stretch the film in the width direction according to the size of the product to be packaged, and the pre-stretching is performed. The stretch wrapping machine according to claim 1 , wherein the amount of stretch is determined based on the size of the product and the detection result of the detection means. 5. The stretch wrapping machine according to claim 1, wherein the film feed mechanism on each side is composed of a conveyor belt and a succession belt consisting of a pair of upper and lower belts, and the pair thereof. A split film clamp is provided on the lower belt of the transport belt of the above, and a patch plate is provided on the upper belt, so that the film end is clamped between the upper and lower belts in cooperation with the patch plate during film transfer. A stretch wrapping machine in which a clamp is urged in a direction of pressing a belt, and the transfer belt constitutes the opening / closing portion of a film feed mechanism.