JPH0912008A - Stretch film packaging machine - Google Patents

Abstract

PURPOSE: To shorten the feeding period of time for a film, and improve the packaging process capability by a method wherein on the upstream side of a film cutter, a film delivering means which transfers and delivers a film leading end to a carrying belt is arranged, and the cutter is controlled in such a manner that it may be operated when a specified quantity of the film is carried. CONSTITUTION: A film 3' is pulled out from a film roll 3, and both side edges of the film 3' in the width direction are gripped by a carrying belt D, and the film 3' is carried to a packaging unit, and at the same time, the film 3' is spanned. Then, an article to be packaged is pushed up by an elevator mechanism 1 from the bottom side of the film 3', and the upper surface of the article to be packaged is covered with the film 3', and the end part of the film 3' is tucked in under the bottom surface of the article to be packaged. In this case, a film cutter E is arranged on the upstream side of the carrying belt D, and a film delivering means C which transfers and delivers the film leading end to the carrying belt D is arranged on the upstream side of the film cutter E. Then, the cutter E is controlled in such a manner that it may be operated when a specified quantity of the film is carried, and by this method, the film 3' can be cut without stopping the carrying belt D.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stretch film wrapping machine, and more specifically, a widthwise end of a stretch film covering an article to be packaged is sandwiched by a conveyor belt. The present invention relates to a packaging machine for pre-stretching in the width direction and packaging.

[0002]

2. Description of the Related Art Generally, when a film drawn from a film roll is cut to a predetermined length in a stretch film wrapping machine of this kind, a predetermined amount of the film is drawn so that the cut edge (cutting edge) is a straight line and the film is conveyed. Was stopped and the cutter was operating. In particular, by changing the amount of pre-stretch in the width direction of the film according to the size of the packaged object, the film cutting is performed by the packaging machine that packages various sizes of the packaged object with one narrow film roll. If the edge is not a straight line, there is a problem that the film will tear during pre-stretching when the amount of pre-stretch is large.Therefore, stop the conveyor belt when cutting the film, and restart the conveyor belt after cutting the film. The length of film was conveyed to the packaging section.

[0003]

For this reason, when the cut film having a predetermined length is conveyed to the packaging unit and is centered at a predetermined position, the film conveying device is restarted to raise the conveying speed. However, it takes an extra time to complete the centering, and as a result, the packaging capacity per unit time is reduced.

Therefore, the applicant of the present application has filed a patent application for a packaging machine which, after pulling out a film for a predetermined length, cuts the film while moving the cutter at the same speed as the film and moves the film to a predetermined position without stopping the film. Flat 6-32821
No. 1 proposes. However, the above packaging machine requires a mechanism for moving the cutter and a mechanism for grasping the trailing end of the cut film, which causes a problem that the structure of the entire apparatus is complicated and the cost is increased.

The present invention has been made in view of the problems of the above-mentioned conventional technique, and the object is to:
It is an object of the present invention to provide a stretch film wrapping machine that can shorten the film supply time and improve the wrapping processing capacity.

[0006]

The technical means taken by the present invention to achieve the above object is to draw out a film from a film roll, and wrap the film by sandwiching both side edges in the width direction with a conveyor belt. It is transported to the department and stretched,
In the stretch film wrapping machine in which the object to be packaged is pushed up from the lower side of the film by the elevator mechanism to cover the upper surface of the object to be packaged with the film and the end portion of the film is folded into the bottom surface of the object to be packaged, the upstream side of the conveyor belt. A cutter for cutting the film, and a film transfer means for transferring and delivering the film front end upstream of the cutter to the conveyor belt at a position upstream of the cutter, and the cutter when the film is conveyed by a predetermined amount. It is characterized by comprising cutter control means to be operated, and conveyor belt control means for continuously operating the conveyor belt after the film is received by the film passing means until the film is conveyed to a predetermined position of the packaging section.

A delivery roller for delivering the film from the film roll may be provided on the upstream side of the film delivery means, and delivery roller control means for stopping the delivery roller at the same time as the operation of the cutter may be provided.

Further, the film is pre-stretched and stretched in the width direction according to the size of the object to be packaged, and the object to be packaged is pushed up from the lower side of the film by an elevator mechanism so that the upper surface of the object to be packaged is formed by the film. In a stretch film wrapping machine for covering a narrow film by pre-stretching the film in the width direction according to the size of the wrapping object before covering and pushing up the wrapping object, the upstream side of the conveyor belt A cutter for cutting the film, and a film transfer means for transferring and delivering the film front end upstream of the cutter to the conveyor belt at a position upstream of the cutter, and the cutter when the film is conveyed by a predetermined amount. After the film is received by the cutter control means to be operated and the film passing means, the film is conveyed to a predetermined position of the packaging section. And a conveyor belt control means for operating the conveyor belt, and further provided with a judgment means for judging whether or not the dimension value of the article to be packaged is larger than a predetermined value, and the conveyor belt control means is provided with the output of the judgment means. When controlling and cutting the film conveyed by a predetermined amount, the output of the judging means is YE.
In the case of S, the transport belt is stopped to cut the film, and when the output of the determination means is NO, the film is cut without stopping the transport belt. The detection means for detecting the size of the article to be packaged is arranged in the middle of transporting the article to be packaged on the mounting table a by the conveyor B to the elevator 1.

[0009]

According to the means of claim 1, when the film is pulled out from the film roll and cut into a predetermined length, the film is cut without stopping the driving of the feeding belt for pulling and feeding the film. The film cut into a predetermined length can be conveyed to a predetermined position in the packaging unit. As a result, the film can be stretched around the packaging portion quickly, and the time required for one packaging can be shortened. According to the second aspect, when the film is cut, the feeding roller for feeding the film from the film roll is stopped at the same time as the operation of the cutter. Therefore, the cutting of the film is instantaneously performed under the condition that the feeding is stopped. , Easy to cut and clean,
The leading edge position of the next film is constant. According to the third aspect of the present invention, the driving and stopping of the conveyor belt at the time of cutting the film are switched and controlled depending on the size of the article to be packaged, so that stable prestretching can be performed while enhancing the processing capacity.

[0010]

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.
A product placing part a for placing an article to be packaged is provided on the side of the machine frame A, and the article to be packaged placed on the product placing part a is conveyed by a conveyor B to an elevator 1 provided inside the machine frame A. . Around the conveyor B, sensors for measuring the width, depth and height of the packaged object are provided. A packaging portion b is provided above the elevator 1, and a film roll arranging portion 2 and a leading end portion of the film 3'unrolled from the film roll 3 set in the arranging portion 2 are held on the side of the packaging portion b. The film transfer means C is provided, and the transport belt D for sandwiching and pulling out the front end of the film held by the film transfer means C and transporting it to the packaging section b is arranged close to the front end of the film transport means C. ,
In addition, a cutter E is disposed between the film passing means C and the conveyor belt D to cut the film held by the conveyor belt and pulled out into a predetermined length. Also, the conveyor belt D
Above and above the left and right folding plates 4, 4'and the rear folding plate 5,
A discharge pusher 6 is arranged above the rear folding plate 5.

Therefore, the object to be packaged placed on the elevator 1 is pushed up with respect to the film 3'extended on the packaging part b by the rise of the elevator, and the end of the film in the stretched state is After the left and right folding plates 4 and 4'and the rear folding plate 5 are folded on the bottom surface of the packaged object,
While the article to be packaged is horizontally pushed toward the ejection section on the front side of the machine frame A by the ejection pusher 6, the front end portion of the film 3 ′ is folded to fold the film.

The film passing means C is a film 3'of the film roll 3 set in the film roll arranging section 2.
As shown in FIG. 3, it holds both sides of the endless belt 7, which is located below the film and is arranged in parallel in the front-rear direction at a distance corresponding to the film width of the film roll 3. Film receiving plate 8 fixed by erection
The holding plate 9 holds a film supported on the surface of the film receiving plate 8 by sandwiching the film with the film receiving plate 8 and a holding roller 10 attached to the holding plate 9, and the holding plate 9 is a machine frame. Protective cover that can be opened and closed with respect to A
11 is slidably supported in the inside of 11 and is also engaged with a film receiving plate 8 that is erected and fixed to the endless belt 7 and slides up and down together, and is sandwiched between the film receiving plate 8 and the holding plate 9. The leading end of the film 3'which is held and held is configured to be able to be transferred to the conveyor belt D. Further, the holding roller 10 attached to the holding plate 9 has its outer surface fitted and projected from the through hole 12 formed in the holding plate 9 into the through hole 17 formed in the film receiving plate 8 to hold the film. 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 7 is wound around a pulley fixed to the rotation shaft of the motor 13, a pulley 15 coaxial with the feeding roller 14, and a driven pulley 16, and is driven by the motor 13. The endless belt 7 is configured to move up and down (rotate) along the moving direction of the film.
Further, the driving of the feeding roller 14 for pulling out and feeding the film of the film roll 3 to the above-mentioned film passing means C is connected to a driving system of a conveyor belt D described later through a pulley, and a transmission pulley 18 in the middle thereof is a brake and a clutch. By means of an attachment, the driving and stopping of the feeding roller are controlled separately from the film passing means C, and are controlled so as to stop at the same time as the operation of the cutter for cutting the film. The film passing means C is the film roll arranging section 2
It is also optional that one or both of the transfer means can be moved in the width direction according to the film width so as to correspond to the film roll to be set in.

The conveyor belt D is a pair of upper and lower endless elastic belts 18 and 18 'that sandwich the side edges of the film in the width direction.
And a clamp plate 19 that presses the lower elastic belt 18 'to the upper elastic belt 18 side, and the lower elastic belt 18' is superposed on the upper surface of the starting end side of the lower elastic belt 18 ', and its tip side is opened and closed. The holding belt 20 is freely movable, and they are arranged in the front and back with the packaging portion b interposed therebetween, and the distance between them is the same as that of the pair of front and rear holding means forming the film passing means C. The pair of front and rear constituent members are supported by the mounting frames 21, 21 ', and the two mounting frames 21, 21' are arranged below the mounting frames 21, 21 'so as to intersect at right angles. It is supported by the rods 22 and 22 'through the connecting members 23 and 23', the mounting frame 21 'to which one of the conveyor belts D1 is attached is fixed, and the attachment frame 21 to which the other conveyor belt D2 is attached is a guide rod. The movable belt 22 is movable along the movable belt 22 and 22 ', and the movable belt D2 is connected with a space expanding means (not shown) so that the distance between the movable belt D1 and the fixed belt D1 can be adjusted. Has been done.

The pair of upper and lower endless elastic belts 18 and 18 'constituting the above-mentioned conveyor belt are driven and rotated in the same direction so that the film can be sandwiched and conveyed, and the driving system is a motor 24 with a speed reducer. Side sprocket that rotates the drive roller around which the elastic belt 18 'is wound and that is fixed to the shaft of the drive roller, and chain sprocket that is fixed to the shaft of the drive roller around which the upper elastic belt 18 is wound. Power is transmitted by winding the chain over and the upper elastic belt 18 is also rotated. 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, the film is arranged symmetrically with respect to the center of the film.

The cutter E, which cuts the film drawn out by the operation of the above-mentioned conveying belt D and the feeding roller 14 to a predetermined length, appears and emerges at a substantially right angle to the film 3'by the control means constituted by the electromagnetic solenoid 25. The film 3'is cut by controlling the energization of the electromagnetic solenoid 25.

Next, regarding the operation of cutting and conveying the film in the above-mentioned packaging machine, (A) the operation of stopping the conveying belt to cut the film and (B) the operation of rotating the conveying belt while the film is being rotated. Operation to disconnect, Figure 5
And it demonstrates based on the time chart of FIG. still,
Switching between (A) and (B) is performed by the film roll placement unit 2
Is determined by the width of the film roll set in and the depth dimension (vertical width) of the packaged object to be wrapped. For example, if the film roll width is 250 mm, and the depth dimension of the packaged object is 150 mm or more, (A) If the depth dimension of the package is less than 150 mm, switch to (B).
Further, the control of driving / stopping the feeding roller for feeding out the film, actuating / stopping the cutter, moving the film passing means C up / down, and driving / stopping the conveyor belt D is performed based on the rotation angle of the cam 26 for driving the elevator. When the cam makes one revolution, one cycle of packaging is performed. The rotation angle of the cam is detected by counting output pulses from the rotary encoder 27 attached to the cam shaft and detecting the count value.

(A) will be described. (See FIG. 5) (I) When the object to be packaged is placed on the product placing portion a and the weighing is completed, the main motor starts rotating. The main motor rotates the cam, and one rotation of the cam causes the elevator to move up and down at the timing shown in the figure. Then, when it is determined that the depth dimension of the package to be waited for is equal to or larger than the predetermined value, the transport belt is stopped to set the mode for cutting the film, and the main motor is set to the low speed mode. At this time, the time chart is 0
Start from ゜. (II) Immediately, the conveyor B is driven, and the object to be packaged that was previously placed and is waiting in front of the elevator 1 is placed on the elevator 1. (III) At almost the same time as the driving of the conveyor B, the film receiving plate 8 and the holding plate 9 which constitute the film passing means C are integrally lowered. (IV) Next, the transport belt D is driven, and the delivery roller 14 is also driven and rotated with a little delay, and the film having the optimum length for the previous packaging of the object to be packaged is pulled out from the film roll 3 and simultaneously stopped. To detect the length of the film pulled out, an optical counter is provided on the rotary shaft of the conveyor belt to measure the amount of movement of the belt. (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 and the cutter E is returned to its original position, and the motor of the conveyor belt D is restarted to position the cut film at the center of the packaging section b. As described above, the conveyor belt D is moved by a predetermined amount and stopped. (VII) The expansion of the film is started at the same time when the conveyor belt D is stopped, and the expansion is completed before the elevator 1 moves up. During this time, the rear folding plate and the left and right folding plates are in the most open state. Then, the carry-in of the packaged goods is completed, the width of the packaged goods weighed this time is detected in the initial stage of the carry-in, and the "depth dimension" is detected in the latter period. It stands by in front of the elevator 1. (VIII) A direction in which the movable conveyor belt D2 of the conveyor belt D, which has expanded the film, is closed while the rear folding plate and the left and right folding plates are started to be closed when the elevator 1 starts to rise and reaches the top. Start to move. By moving the movable conveyor belt D2 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 pressing belt provided on the upper end side of the conveying belt D.
The starting end side of 20 rotates upward, and then the film passing means C is raised to the side of the conveyor belt D. At this time, the feeding roller 14
Is in a state of free rotation, and since the holding roller provided in the film passing means C holds the film, the film 3'is pulled out by the rising of the film passing means C,
The leading edge of the film is the lower elastic belt of the conveyor belt D.
Position it between 18 'and the presser belt 20. Then, the film can be pulled out by the next conveyor belt D, and one packaging cycle is completed.

As for (B), the depth dimension of the article to be packaged that has been previously loaded and is on standby is 150 during the above process.
The operation when it is detected to be less than mm can be considered as the operation following (IX). (See Fig. 6) (X) When the next item to be packaged is weighed, determine if the depth dimension of the item to be packaged on standby is less than 150 mm,
Since the determination result is “YES”, the film is cut while the transport belt D is being driven and rotated, and the main motor is set to the high speed mode to start. (XI) Same as (II) of (A). (XII) Same as (III) of (A).

(XIII) The conveyor belt D is rotated first, and then the feeding roller 14 is driven and rotated to operate the cutter E immediately before pulling out the film of the optimum length from the film roll 3 for the object to be packaged waiting on the film roll 3. Let the film cut to the correct length. When the feeding roller 14 is pulled out for a predetermined length, the feeding roller 14 turns off the clutch of the transmission pulley 18 and turns on the brake so that the feeding roller 14 does not interlock with the conveyor belt D.
14 is stopped suddenly. (XIV) After cutting the film, the electromagnetic solenoid is turned off and the cutter E is returned to the original position. (XV) The conveyor belt D is continuously operated from the above (XIII) until the cut film reaches the centering position. After that, it is the same as (VII) of (A).

Comparing (A) and (B) above, the centering end time of the film is about 1.
0 seconds, about 0.7 seconds in the case of (B), and 0.
You can see that it is about 3 seconds earlier. Therefore, the subsequent operation can be started earlier correspondingly, and as a result, the packaging processing capacity can be improved. It should be noted that it is more preferable from the standpoint of packaging finish that the switching between the modes (A) and (B) described above is performed not only by determining the depth dimension of the packaged object but also by determining the height dimension. In the type in which the film is drawn out from the rear of the packaging machine to the front, the width dimension of the packaged object should be judged. The dimension data may not be obtained by being detected, but may be set and called for each product in advance.
Further, the driving of the feeding roller 14 is not limited to the structure linked to the drive system of the conveyor belt D shown in the embodiment, and it is operated by an independent drive system different from the drive system of the conveyor belt D. May be. Furthermore, the film passing means is not limited to the form of the above-mentioned embodiment, but may be a type of gripping and passing the leading end of the film. Further, although the present embodiment was carried out for the type in which one film roll is mounted, a packaging machine of the type in which a plurality of film rolls having different film widths are mounted is also applicable to claims 1 and 2. Not only the above, but also the type in which the pre-stretch amount is changed according to the size of the packaged object can be applied to claim 3.

[0024]

The stretch film packaging machine according to the present invention has the structure of claim 1 and can cut the film without rotating the conveyor belt, so that the conveyor belt is stopped and restarted. In this case, there is no rise time, and the cut film can be stretched quickly at a predetermined position in the packaging portion, and the packaging processing speed can be increased. In the case of the configuration described in claim 2, since the film can be instantaneously stopped from being fed by the feeding roller when the film is cut,
Cutting is stable, and the position of the leading edge of the next film can be made constant. Further, in the case of the configuration described in claim 3, the operation is not uniform for all the objects to be packaged, and the film is cut while the conveyor belt is rotated for the objects to be packaged with a small film expansion amount. Therefore, the packaging capacity can be increased without any problem.

[Brief description of the 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 view showing a film transfer section from the film transfer means to the conveyor belt.

FIG. 4 is an enlarged view showing a state in which a film passing means is raised to pass a film to a conveyor belt.

FIG. 5 is a time chart when the transport belt is stopped and the film is cut.

FIG. 6 is a time chart when the film is cut while the transport belt is rotated.

[Explanation of Codes] C ... Film passing means D ... Conveying belt E ... Cutter 1 ... Elevator 3 ... Film roll 14 ... Delivery roller

Claims (3)

[Claims] 1. A film is pulled out from a film roll, and both side edges of the film in the width direction are sandwiched by a conveyor belt to be conveyed and stretched to a wrapping section, and an object to be packaged is mounted from below the film by an elevator mechanism. In a stretch film wrapping machine that pushes up and covers the upper surface of the packaged object with a film, and folds the end of the film to the bottom surface of the packaged object, a cutter that cuts the film upstream of the conveyor belt and a position upstream of the cutter. Is provided with a film transfer means for transferring and delivering the film front end upstream from the cutter to the conveyor belt, and a cutter control means for activating the cutter when the film is conveyed by a predetermined amount, and the film transfer means. The conveyor belt that continuously operates the conveyor belt after receiving the film until the film is conveyed to a predetermined position in the packaging unit. A stretch film wrapping machine comprising: 2. A feeding roller for feeding a film from a film roll is provided on the upstream side of the film passing means, and a feeding roller control means for stopping the feeding roller at the same time as the operation of the cutter is provided. The stretch film packaging machine according to claim 1. 3. A film is pulled out from a film roll, and both side edges of the film in the width direction are sandwiched by a conveyor belt to be conveyed and stretched to a wrapping section. While pushing up to cover the upper surface of the packaged object with a film, pre-stretching the film in the width direction according to the dimensions of the packaged object before pushing up the packaged object performs packaging using a narrow film. In a stretch film wrapping machine, a cutter for cutting a film on the upstream side of the conveyor belt, and a film passing means for transferring and delivering a film tip on the upstream side of the cutter to the conveyor belt at a position upstream of the cutter, In addition, the film is moved by the cutter control means for activating the cutter when the film is conveyed by a predetermined amount and the film passing means. And a conveyor belt control means for operating the conveyor belt until the film is conveyed to a predetermined position of the wrapping section, and further provided with a judgment means for judging whether or not the dimensional value of the object to be packaged is larger than a predetermined value. When the output of the determination means controls the conveyor belt control means to cut the film conveyed by a predetermined amount, when the output of the determination means is YES, the conveyor belt is stopped to cut the film, and the determination means When the output is NO, the stretch film wrapping machine is characterized by cutting the film without stopping the conveyor belt.