JPH09207904A - Stretch film packaging machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a stretch film packaging machine which can immediately detect it when a wrong transfer of the film is generated. SOLUTION: This packaging machine is constituted in such a manner that a film is let off from a film roll 3, and at the same time, the film being cut by a specified length, is transferred to a packaging position and stretched by a film transfer means D. In this case, in the middle of a transfer path of the film from the film roll 3 to the packaging position, wrong transfer detecting sensors F, F' which detect whether the film is normally transferred by the film transfer means D or not, are provided, and when the generation of an abnormality in the transfer of the film is detected by the sensors, the state is immediately alarmed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention stretches a film of a predetermined length unwound from a film roll on a wrapping portion, pushes up the article to be packaged from below with respect to the film, and the surface of the article to be packaged is described above. The present invention relates to a stretch film packaging machine for packaging with a film.

[0002]

2. Description of the Related Art A conventional stretch film wrapping machine detects that the film of a film roll set in the wrapping machine has run out, that is, a so-called film end is detected, but a predetermined length unrolled from the film roll. Whether the film of No. has been normally transferred to the specified position (packing section),
That is, no error in the transfer of the film was detected.
A film transfer error is an error in which the film is not transferred to a specified packaging part for some reason despite the presence of the film (not the film end). The main cause is the film supply roller (film roll). It is conceivable that the film is wrapped around a roller arranged between the film transfer means and the film transfer means.

As a conventional method of detecting the film end, a micro switch is built in the film supply roller arranged between the film roll and the film transfer means, and the film is attached to the peripheral surface of the film supply roller. When passing (when there is a film), the film tension acts on the microswitch to detect "film present", and when the film tension does not act on the microswitch, "no film" is detected. There are two types: a method in which a tension roller is arranged between the film roll and the film supply roller, and when the film runs out, the tension roller moves downward to detect it. This is done by detecting the decrease in tension due to In can not transfer miss detection of the film.

[0004]

Therefore, conventionally, when the film is not transferred to a predetermined wrapping portion due to the film being wound around the film supply roller, the wrapping naturally fails, but conventionally, such a wrapping is not possible. The failure cannot be detected automatically, and therefore the worker notices that the packaged product (product) delivered from the packaging machine is not packaged and notices that a film transfer error has occurred for the first time. It will be. However, since the work of the worker is to put the article (product) to be packaged on the mounting table, the discovery of the packaging failure tends to be delayed.

That is, normally, the detection of a film transfer error is delayed, and during that time, the packaging machine operates in vain, and when the packaging machine is a weighing and packaging pricing machine, the unwrapped object is labeled. Will be attached, labels will be wasted, and troublesome work such as correction of production performance data will be required. Further, when the cause of the film transfer error is winding around the film supply roller, the degree of winding becomes severe, it takes a very long time to bring the film into a normal state, and the film is wasted. Therefore, if a film transfer error occurs, it is desired that the fact be immediately detected. The present invention has been made in view of the problems of the above-mentioned conventional techniques, and an object of the present invention is to provide a stretch film packaging machine capable of immediately detecting a transfer error of a film. To provide.

[0006]

Means for Solving the Problems The technical means taken by the present invention to achieve the above object is to ensure that the film is normally transferred by the film transfer means during the transfer path of the film from the film roll to the packaging position. A transfer error detection sensor for detecting whether or not the film has been transferred is provided, and when the sensor detects that an error has occurred in the transfer of the film, it is configured to give an alarm immediately. When the above-mentioned transfer error is detected, in addition to the alarm to that effect, at least a part of the operation of the packaging machine, for example, the operation of the film transfer means is stopped. Of course, all the operations of the apparatus may be stopped including the carrying-in means for sending the article to be packaged onto the elevator.

The position in the transfer path of the film from the film roll in which the above-mentioned transfer error detection sensor is arranged to the packaging position is inside the vicinity of the starting end portion where the leading end of the film in the film transfer means is received and clamped, or the packaging portion. , The tip of the film holding means for delivering the tip of the film to the film transfer means, the inside of the film supply roller, the position between the film roll and the film supply roller, and the like. It is only necessary to be able to detect a transfer error that has occurred during the period. The transfer error detection sensor may also serve as a film end detection sensor for detecting the absence of film on the film roll, and of course, a film end detection sensor may be separately provided.

Further, the type of the above-mentioned transfer error detection sensor may be a reflection type sensor or a micro switch, and the number of the sensors installed is not limited to a form in which a pair (two) is provided inside a pair of film transfer means. , 3 along the width direction of the film, or 1 at a position corresponding to the approximate center position of the film width, and 1 or 2 to 3 at each of the plurality of installation positions selected from the above-mentioned plurality of installation positions. It is possible to install such as. According to the above means, when a film transfer error occurs, an alarm to that effect is immediately issued, so that the wasteful operation of the packaging machine can be minimized, and the weighing and packaging pricing machine can be used. In the case of, the label will not be wasted and attached in vain.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. The stretch film wrapping machine shown in FIG. 1 and FIG. 2 is provided with a product placing section (weighing section) a for placing an article to be packaged in front of a machine frame A, and the article to be packaged placed on the article placing section a. Is conveyed by the pusher conveyor B to the elevator 1 provided inside the machine frame A. At the side of the pusher conveyor B, sensors for measuring the width, depth and height of the packaged object are provided. A packaging part b is provided above the elevator 1, and a film 3 fed from a film roll arranging part 2 and a film roll 3 set in the arranging part 2 is provided on the side (right side in FIG. 2) of the wrapping part b. '
Is provided with a film holding means C for holding the leading end of the film holding means C, and the film feeding means D for nipping and pulling out the leading end of the film held by the film holding means C and transferring it to the packaging section b is the leading end of the film holding means C. The film holding means C and the film transporting means D.
A cutter E for cutting the film 3 ′ held by the film transporting means D and pulled out to a predetermined length is disposed between and. Further, right and left folding plates 4 and 4 ′, a rear folding plate 5, and a discharge pusher 6 are disposed above the film transporting means D and above the rear folding plate 5.

Therefore, the object to be packaged placed on the elevator 1 is pushed up by the lift of the elevator 1 with respect to the film 3 ′ stretched in the packaging part b, and the end portion of the film in a stretched state. The left and right folding plates 4, 4 '
After being folded into the bottom surface of the package by the and the rear folding plate 5, the film is pushed by the discharge pusher 6 while horizontally pushing the package to the discharge section (heat seal section) 7 on the front side of the machine frame A. The front end of 3'is folded by the front folding roller 7'to the bottom of the article to be wrapped, and the folding of the film is completed. When the stretch wrapping machine is a weighing and wrapping price machine, a label is attached during the transfer by the discharge pusher 6.

The film holding means C is a film 3'of the film roll 3 set in the film roll arranging section 2.
The film which holds the front end portion of the film and is erected and fixed over the endless belt 8 which is located below the film and is arranged in parallel in the front-rear direction at a predetermined interval in parallel as shown in FIGS. A holding plate 8 ', a holding plate 9 having the same shape for holding the film supported on the surface of the film receiving plate 8'by the film receiving plate 8', and a holding member attached to the film receiving plate 8 ' Holding plate 9 composed of roller 10
Is vertically slidably supported inside a protective cover 11 which is openable and closable with respect to the machine frame A, and is attached together with a film receiving plate 8 ′ which is erected and fixed on an endless belt 8. The tip of the film 3'which slides up and down and is sandwiched and held by the film receiving plate 8'and the holding plate 9 can be delivered to the film transfer means D. Further, the holding roller 10 attached to the film receiving plate 8 ′ has its outer surface fitted into and protruding from the through hole 12 formed in the receiving plate 8 ′ into the through hole 17 formed in the holding plate 9. 'Holds the roller
The film is surely held by making it meander along the peripheral surface of 10 and the holding roller 10 is configured to be rotatable only in the film withdrawing direction.

Further, the endless belt 8 is wound around a pulley fixed to the rotation shaft of the motor 13, a pulley 15 coaxial with the feeding roller (film supply roller) 14, and a driven pulley 16. The endless belt 8 is configured to be vertically moved (forward / reverse rotation) along the moving direction of the film by driving the motor 13. Further, the drive of the feeding roller 14 for pulling out and supplying the film of the film roll 3 to the above-mentioned film holding means C is connected to the drive system of the film transfer means D described later through a pulley, and a transmission pulley (not shown) in the middle thereof. ) Is equipped with a brake and a clutch, and the driving and stopping of the feeding roller are controlled separately from the film holding means C, and are controlled so as to stop simultaneously with the operation of the cutter for cutting the film. Furthermore, the film receiving plate 8 ′ constituting the film holding means C
A plurality of notches 42 are formed on the upper end of the holding plate 9 so as to correspond to the film rolls having different film widths, and one end in the width direction is used as a reference. The film is configured to be handed over. The film holding means C is divided into two in the width direction so that one or both of the holding means can be moved in the width direction according to the film width so as to correspond to the film roll set in the film roll arranging section 2. The configuration is also optional.

The film transfer means D comprises a pair of upper and lower endless elastic belts 18 for sandwiching the side ends of the film in the width direction.
18 ', a clamp plate 19 for pressing the lower elastic belt 18' to the upper elastic belt 18 side, and the starting end side of the lower elastic belt 18 'is inclined downward toward the film holding means C side. The pressing belt 20 is arranged so as to overlap with the upper surface of the downwardly inclined starting end side, and the distal end side of the pressing belt 20 is openable and closable, and they sandwich the wrapping portion b as shown in FIG. It is arranged in a position to sandwich the side end portions of the film 3 ′ pulled out from the film roll 3 in the front and rear. The pair of front and rear components is supported by the mounting frames 21 and 21 ', and the mounting frames 21 and 21' are arranged at right angles to the lower side of the mounting frames 21 and 21 '.
The frame is supported by the guide rods 22 and 22 'of the book via the connecting members 23 and 23', and the mounting frame 21 to which one film transfer means D1 is mounted is fixed, and the other mounting frame to which the film transfer means D2 is mounted. 21 'is configured to be movable along the guide rods 22 and 22', and the film transfer means D2 on the movable side thereof.
A space expanding means (not shown) is connected to the device so that the space between the fixed film transfer means D1 and the film transfer means D1 can be adjusted to be wide or narrow.

The pair of upper and lower endless elastic belts 18 and 18 'constituting the above-mentioned film transfer means are driven and rotated in the same direction so that the film can be nipped and conveyed. The driving system is a motor 24 with a speed reducer. The lower elastic belt 18 'rotates the drive roller 18'a that is wound, and the chain sprocket (not shown) fixed to the shaft of the drive roller and the upper elastic belt 18 are wound. The chain is wound around a chain sprocket (not shown) fixed to the shaft of the drive roller 18a to transmit power, and the upper elastic belt
The 18 is also configured to rotate. Further, the clamp plate 19 for pressing the lower elastic belt 18 'to the upper elastic belt 18 is not limited to the three divisions shown in the figure, but may be four or more divisions. As shown in the drawing, they are arranged symmetrically with respect to the center of the packaging part b.

The cutter E, which cuts the film drawn out by the operation of the film transfer means D and the feeding roller 14 to a predetermined length, is made substantially perpendicular to the film 3'by the control means constituted by the electromagnetic solenoid 25. It is configured to project and retract, and the film 3'is cut by controlling the energization of the electromagnetic solenoid 25.

Then, as shown in FIGS. 2 and 3, the front and rear film transfer means D1 in the film transfer means D are used.
Transfer error detection sensors F and F ', which are reflection type sensors, are installed and fixed to the inside of the vicinity of the start end side of D and D2 via mounting brackets on the mounting frames 21 and 21' on which the film transfer means D1 and D2 are supported. Has been done. Further, the shaft of the pulley around which the lower elastic belt 18 'of the film transfer means D is supported is provided with receiving rods 41, 41' for preventing the film from hanging down toward the inside, whereby the film transfer means. The center portion of the film sandwiched by D in the width direction is configured to prevent the film from hanging down and touching other portions.

FIG. 4 shows the electrical construction of the above-mentioned apparatus, which comprises a weighing label printer control unit G and a packaging mechanism control unit H, and the weighing label printer control unit G mainly controls the weighing label printer. Since it is carried out and is not directly related to the present invention, illustration and description thereof will be omitted, and the packaging mechanism control unit H related to the present invention will be described. The packaging mechanism controller H mainly controls the mechanism of the packaging machine C
It is controlled by the PU 26.

The CPU 26 is provided with a communication interface circuit (INF) 27, a ROM 28, a RAM 29, a bus 26a,
The operation unit 30, the display unit 31, and the mechanism drive unit 32 are connected. The communication interface circuit (INF) 27 is a circuit for communicating various data and commands with the measurement label printer control unit G. The ROM 28 stores a control program executed by the CPU 26. RAM29 is the CPU
In addition to the areas of various registers and flags used when 26 executes the control program of ROM 28, various tables for determining control data based on the shape data (length, width, height) of the product are stored. There is. The operation unit 30 includes various switches for starting and stopping the device and a keyboard for inputting data. The display unit 31 is composed of a dot-type liquid crystal display device, and displays input data, preset data, based on a command from the CPU 26.
It displays various messages such as "film transfer error" and "film end", and is also known as the console section.

The mechanism drive unit 32 is a circuit for driving each mechanism unit of the packaging machine when executing packaging, and specifically, the motor 33 for driving the elevator 1 and the drive motor for the conveyor B for carrying in products. 34, drive motor for film transfer means D
24, a drive motor 36 for actuating the left and right folding plates 4, 4'for folding the left and right ends of the film into the bottom of the product, a drive motor 37 for operating the rear folding plate 5 for folding the rear end of the film into the bottom of the product, discharge There are a drive motor 38 for operating the pusher 6, a film transfer error detection sensor F, F ', and a rotary encoder 40 for detecting the rotation angle of a cam 39 for driving the elevator 1. The film transfer error detection sensors F and F ′ indicate whether or not the leading edge of the film 3 ′ held by the film holding means C has been transferred to the film transfer means D and has been normally transferred to a predetermined position (packing section b). The presence or absence of the film is supplied to the CPU 26. The configuration of the packaging machine has been briefly described above, but the details of the control of other motors not directly related to the present invention will be omitted. The rotary encoder 40 is attached to the shaft of a cam 39 that drives an elevator, counts output pulses from the rotary encoder 40, and detects the rotation angle of the cam by the counted value. Then, based on the rotation angle of the cam, control of [loading process], [pushing up process], [folding process], [unloading process], and [film transfer process] is performed. When the cam 39 makes one revolution, the operation of one cycle of the packaging machine is completed. Then, the status signal (normal, error, etc.) of each control unit is exchanged between the packaging mechanism control unit H and the weighing label printer control unit G (not shown).

Next, the mechanical time chart of the above-mentioned packaging machine will be described with reference to FIG. 5 regarding the operation in the case of cutting the film by stopping the film transfer means.
The switching between cutting the film with the film transfer means stopped and with the film transfer means being driven and rotated is performed for the film roll width set in the film roll placement unit 2 and for the packaging. Determined according to the depth dimension (vertical width) of the packaged item. In addition, drive / stop of the feeding roller 14 for feeding the film, operation of the cutter E,
A cam that drives the elevator 1 is controlled by stopping, moving the film holding means C up and down, and driving and stopping the film transfer means D.
Based on the rotation angle of 39, when the cam makes one rotation, one cycle of operation of the packaging is performed. The rotation angle of the cam is detected by counting the output pulses from the rotary encoder 40 attached to the cam shaft as described above and detecting the count value.

(I) When the object to be packaged is placed on the product placing portion (weighing portion) a and the weighing is completed, the drive motor 33 starts to rotate. This drive motor 33 rotates the cam 39,
The rotation causes the elevator to move up and down at the timing shown.
Then, when the previously measured depth dimension of the packaged object waiting in the middle of the conveyor (before the elevator 1) is equal to or larger than the predetermined value, the film transfer means D is stopped to set the mode for cutting the film, and The drive motor 33 is set to the low speed mode. When the drive motor 33 starts rotating, the time chart starts from 0 °. (II) Immediately after the conveyor B is driven, the object to be packaged that was previously placed and is waiting in the middle of the conveyor B is placed on the elevator 1 (at the same time, the products on the product placing part a are conveyed to the middle of the conveyor B. Yes.). (III) The pressing belt 20 of the film transfer means D is closed almost at the same time as the driving of the conveyor B, and after the closing movement of the pressing belt 20 is completed, the film receiving plate 8 constituting the film holding means C.
And the holding plate 9 are integrally lowered (in the initial position, the holding belt 20 is located at the open position and the film holding means C is located at the upper position). (IV) Next, the film transfer means D is driven, and the feeding roller 14 is also driven and rotated with a little delay to pull out the film of the optimum length for packaging the object to be packaged from the film roll 3, and then simultaneously stopped. In order to detect the length of the drawn film, an optical counter is provided on the rotating shaft of the film transfer means D to measure the amount of movement of the belt. Then, the presence or absence of the film is detected by the transfer error detection sensors F and F ′ during the film pulling operation of the film transfer means D (see the detection timing in FIG. 5). That is, the operation of detecting a film transfer error shown in FIG. 6 described later is executed. (V) Next, the electromagnetic solenoid 25 for moving the cutter E to the film side is turned on and the cutter is operated to cut the stopped film 3'to form a clean straight cutting edge.

(VI) After cutting the film, the electromagnetic solenoid is turned off to return the cutter E to its original position, and the drive motor 24 of the film transfer means D is restarted to cut the cut film in the packaging section b. The film transfer means D is moved by a predetermined amount so as to be positioned at the center and stopped. (VII) At the same time when the film transfer means D is stopped, one film transfer means D2 is moved in a direction away from the other film transfer means D1 to start the expansion of the film, and the expansion is completed before the elevator 1 moves up. To do. During this time, the rear folding plate 5 and the left and right folding plates 4 and 4'are in the most opened state. Then, the operation of the conveyor B is also completed, the "width" of the object weighed this time is detected in the initial stage of the carry-in, and the "depth dimension" is detected in the latter stage of the package B.
Before (). (VIII) At the time when the elevator 1 starts rising and reaches the apex, the rear folding plate 5 and the left and right folding plates 4 and 4'begin to be closed, and at the same time, the movable side of the film transfer means D, which is expanding the film, is moved. The film transfer means D2 starts to move in the closing direction. This movable film transport means D
By moving 2 in the closing direction to weaken the film expansion, the tension of the film is relaxed.

(IX) When the folding of the end portion of the film is completed, the start end side of the holding belt 20 provided above the start end side of the film transfer means D is rotated upward, and then the film holding means C is moved by the film transfer means D. Be raised to the side. At this time, the feeding roller 14 is in a freely rotating state, and the holding roller provided in the film holding means C holds the film.
Is pulled out, and the leading end of the film is positioned between the lower elastic belt 18 'and the holding belt 20 in the film transfer means D. With this, the film can be pulled out by the next film transfer means D, and one packaging cycle is completed.

FIG. 6 is a flow chart showing the control of the transfer error detection which is carried out during the above-mentioned film drawing operation, which is executed by the CPU 26. (Start) ... This process starts at the start of the film transfer operation. Specifically, when the film transfer means D clamps the leading end of the film 3'by closing the pressing belt 20. (SP1) ... It is judged whether the transfer error detection sensor F or F'detects "no film". (YES) → To SP2 (NO) → To SP4 (SP2) ... The driving of the film transfer means is stopped. (SP3) ... It warns that a film transfer error has occurred. The content of the alarm is displayed, for example, in characters on the display unit 31 of the packaging machine. The fact is displayed in characters on the display unit of the printer. Turn on the lamp that indicates that an error has occurred. Sounds a buzzer indicating that an error has occurred. It gives a voice warning that an error has occurred. Therefore, any one of or is selected, or a plurality of or is used in combination. (SP4) ... It is determined whether or not the drawing of the film of the predetermined length is completed. (NO) → SP1 and subsequent steps are repeated. (YES) → Return (end of processing) Since the transfer error detection sensors F and F ′ are installed inside the starting end side of the film transfer means D as shown in the figure, after cutting the film of a predetermined length, the film is wrapped. Since no film is used when the sheet is conveyed to the portion b, the check is not performed during this period (after the operation of the cutter E).

Arrangement positions of the above-mentioned transfer error detection sensors F and F'for detecting the transfer error of the film are not limited to those in the illustrated embodiment. That is, it suffices that a transfer error of the film can be detected as a result. A possible modification of the arrangement position of the transfer error detection sensors F and F'is provided in (a) the packaging part b (downstream side of the illustrated embodiment).
If there is no film at the specified position when the process of transferring the film to the specified position is completed, it is determined that the film has been transferred incorrectly. (b) Provided in front of the film transfer means. For example, it is provided at the leading end of the film holding means C, and if there is no film, it is determined that the transfer is wrong. (c) If the film supply roller (feeding roller 14) is normal, the film supply roller is provided on the periphery facing the outer peripheral surface where no film exists. Detects whether the film is wrapped around the supply roller. If the film is detected, it means that the film is wrapped around the supply roller, and a transfer error is detected. (d) Provided between the supply roller and the film roll. If the film is wound around the supply roller or if the film transfer means fails when the film is nipped, the tension applied to the film changes (decreases) as compared with the normal state because the film is not fed out during the film transfer. This change in tension is detected by the position of the tension roller or the output change of the tension detecting means. And the like. Therefore, it may be installed at a plurality of locations in combination with (a) to (d) and the embodiment.

Further, the above-mentioned transfer error detection sensor F,
The type of F ′ is not limited to the embodiment, and a micro switch or the like may be used. Further, the number of transfer error detection sensors is not limited to that in the embodiment (two), and for example, a total of three may be arranged between a pair of front and rear transfer means forming the film transfer means D, or one in the center. Alternatively, a plurality of them may be provided in the packaging portion b, and one at the tip of the film holding means C in addition to the embodiment.

In the above-described embodiment, when a film transfer error is detected, the film transfer means D is immediately stopped, but the conveyor B for transporting the article to be packaged to the elevator 1 is not stopped. This is because, if the conveyor B is stopped halfway, it must be returned to the initial position when the device is used again (if the conveyor B is not stopped, the packaged product conveyed to the predetermined position is transported). All you have to do is collect the items). However, it is of course possible to stop all the operations of the apparatus including the conveyor B.

The film transfer error detection sensor in the embodiment also serves as the film end detection sensor. This is because the operator needs to take measures when reusing (restarting) both in the case of a transfer error and the film end, so that the operator can make a judgment. However, it is of course possible to separately provide a film end detection sensor as in the conventional case and display the film transfer error and the film end separately. Further, the specific configuration of the stretch film wrapping machine is not limited to the embodiment, and if the stretch film wrapping machine of the type that unwinds the film from the film roll and stretches it on the wrapping section, the purpose is to carry out The effect is obtained. However,
It is necessary to adopt a method suitable for each configuration for the location of the sensor, the number of sensors, and the detection timing. The point is that when the film is transferred, it may be possible to eventually detect by some means that there is no film in the portion where the film should exist.

[0029]

According to the stretch film wrapping machine of the present invention, when a film transfer error occurs, an alarm is immediately (in real time) issued to the operator, so that the operator can immediately Since the device can be stopped, useless operation of the packaging machine can be minimized. Therefore, when the film is wound around the film supply roller, it can be found before the degree of the winding becomes serious, and it is possible to prevent the film from being wasted without reusing it. Then, when the packaging machine is a weighing and packaging pricing machine, it is possible to prevent the label from being wasted and attached unnecessarily.
Further, in the case of the configuration of claim 2, since a part of the operation of the packaging machine is automatically stopped at the same time when the film transfer error occurs, the operator does not perform any operation and the useless operation of the packaging machine is performed. Can be minimized.

Further, in the case of the constitutions of claims 3 and 4,
Since the transfer error detection sensor directly determines the presence or absence of the film, the transfer error can be detected accurately and reliably. In the case of the configuration of claim 5, the cost of the apparatus can be reduced because it is not necessary to separately provide a conventional sensor for detecting the film end. Further, according to the seventh and eighth aspects, when either one of the pair of transfer means does not hold the film at the time of transferring the film, the fact can be detected immediately, and the detection of the transfer error of the film can be promptly and reliably performed. It can be carried out.

[Brief description of drawings]

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

2 is a vertical front view of FIG. 1. FIG.

FIG. 3 is an enlarged cross-sectional view taken along the line (X)-(X) of FIG.

FIG. 4 is an explanatory diagram showing an electrical configuration of control means of the apparatus.

FIG. 5 is a mechanical time chart of the device.

FIG. 6 is a flowchart showing detection control of a film transfer error.

[Explanation of symbols]

C ... Film holding means D ... Film transfer means E ... Cutter F, F '... Transfer error detection sensor 1 ... Elevator 3 ... Film roll

Claims (8)

[Claims] 1. A stretch film wrapping machine for feeding a film from a film roll and transferring a film of a predetermined length to a wrapping position by a film transfer means to stretch the film, the transfer path of the film from the film roll to the wrapping position. A transfer error detection sensor for detecting whether or not the film is normally transferred by the film transfer means is provided therein, and when the sensor detects that an error has occurred in the transfer of the film, an alarm to that effect is immediately issued. A stretch film packaging machine characterized by being configured as follows. 2. The stretch film packaging machine according to claim 1, wherein at least a part of the operation of the packaging machine is immediately stopped when an abnormality occurs in the transfer of the film. 3. The stretch film packaging machine according to claim 1, wherein the transfer error detection sensor directly detects the presence or absence of a film to be transferred. 4. The stretch film packaging machine according to claim 3, wherein the transfer error detection sensor is a reflective sensor. 5. The stretch film packaging machine according to claim 1, wherein the transfer error detection sensor also detects the end of the film roll. 6. The transfer error detection sensor is arranged downstream of a film supply roller arranged in a film transfer path from the film roll to the film transfer means. Stretch film wrapping machine. 7. The film transporting means comprises a pair of film transporting mechanisms for sandwiching and transporting both side edges of the film in the width direction, and the transport error detection sensor is located inside the pair of film transporting mechanisms in the vicinity of the starting ends. The stretch film wrapping machine according to claim 1, wherein the stretch film wrapping machine is arranged respectively. 8. A film holding means for holding the leading end side of the film fed from the film roll is arranged on the upstream side of the film transfer means, and a cutter is arranged between the film holding means and the film transfer means. The film holding means is vertically movable toward the starting end side of the film transporting means, and by the upward movement of the film holding means, the leading end portion of the film can be handed over to the starting end side of the film feeding means, and inside the starting end side of the film feeding means. The stretch film packaging machine according to claim 7, further comprising a pair of transfer error detection sensors.