JP3267121B2 - Stretch film packaging 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 film wrapping machine, and more particularly to a stretch film covering an object to be wrapped, the widthwise end of which is sandwiched between transport belts, and the transport means is driven to place the film on the wrapping portion. The present invention relates to a packaging machine that stretches and packs.

[0002]

2. Description of the Related Art In a conventional stretch film packaging machine of this type, it is necessary to hold the leading end of a film fed from a film roll between conveying means by some means. Therefore, in a stretch film packaging machine as disclosed in JP-A-6-183417, the left and right ends of the cut film on the film roll side are gripped by a film gripper, and the film gripper is moved to a transporting device by a transport device. By doing so, the film was sandwiched between the conveyor belts. As a result, high speed of film feeding and easiness of film width switching have been obtained.

[0003]

However, in the above-described method, when the film gripper takes the film to the transport belt, it does not shift the gripped film, but it does. After that, it is necessary to slide the gripper and the film to pull out the film with the conveyor belt,
An appropriate gripping force that satisfies both of these is a very delicate value. For this reason, the friction between the film and the gripper changes due to the influence of temperature, humidity, and the like, and there has been a problem that the delivery or unwinding of the film is not performed properly. SUMMARY OF THE INVENTION The present invention has been made to solve this problem, and an object of the present invention is to provide a stretch film packaging machine which has a simple mechanism and can reliably deliver and deliver a film.

[0004]

In order to achieve the above-mentioned object, the present invention provides a technical means in which a film is fed from a film roll, and both side edges in the width direction of the film are sandwiched by a conveying means for packaging. Stretch film packaging that is conveyed to a part and stretched, the object to be packaged is pushed up by an elevator mechanism from the lower side of the film, the upper surface of the object to be packaged is covered with the film, and the end of the film is folded into the bottom of the object to be packaged. And a cutter for cutting the film upstream of the transport means in the film traveling direction, and transporting the film tip upstream of the cutter to the transport means while maintaining a straight state to the transport means. An upper and lower holding plate provided with a notch at a position corresponding to the conveying means, and a film rotatable only in the film feeding direction and A holding roller that has been subjected to a surface treatment capable of holding in close contact, and a moving unit that simultaneously moves the holding plate and the holding roller to transfer the leading end of the film from a position before the cutter to a position of the conveying unit. I do.

Here, the holding plate is composed of two upper and lower flat plates. By holding the film between the two flat plates, the leading end of the film is kept straight. The shape of the holding plate is not limited to a flat plate, but may be a cloth stretched on a frame, a net, or a punching plate.

The holding roller only needs to be supported on both ends of the upper or lower holding plate, and can be rotated only in the film feeding direction by a one-way clutch or the like. The surface of the holding roller is mirror-finished to improve the adhesion of the film, but these surface treatments involve winding some member around the roller surface without directly applying it to the roll. But it is good.

[0007] The moving means comprises an upper and lower holding plate supported by a slide rail, and an endless belt having a drive unit engaged with one of the upper and lower holding plates.

According to a second aspect of the present invention, the holding roller is characterized in that the adhesiveness of the film at the central portion in the axial direction is lower than at both ends. As a means to lower the adhesion,
A method of performing knurling or the like on the surface of the holding roller, or a method of providing a cover member that covers the outer peripheral surface of the holding roller to block contact between the surface of the holding roller and the film may be used.

According to a third aspect of the present invention, the diameter of the holding roller at the central portion in the axial direction is smaller than that at both ends.

According to a fourth aspect of the present invention, the holding roller is divided and arranged only near both ends in the film width direction.

According to a fifth aspect of the present invention, the interval between the left and right transfer means can be changed in a plurality of steps, and the upper and lower holding plates are provided with cutouts at respective set positions of the respective transfer means. Features. The distance between the transport belts may be changed by fixing one of the transport belts at a reference position and moving the other, or by uniformly moving the left and right transport belts based on the center of the film width.

According to the present invention, of the upper and lower holding plates, the holding plate closer to the outside of the main body can be opened and closed, and the guide member for guiding the leading end of the film to the outside can be opened and closed. Provided on the support member of the plate, and its installation position,
It is characterized in that the holding plate is on the downstream side in the film advancing direction from the position where the film is cut by the cutter when the holding plate is closed. The guide member has a length at least equal to or greater than the maximum film width, and is a flat plate whose entire surface or a part is mirror-finished, but may be bent into an L-shaped cross section. Further, the whole or a part of the square pipe or the angle iron may be mirror-finished and used.

According to a seventh aspect of the present invention, a cutter receiver is provided which can reciprocate between a position where the leading end of the film is cut and a retracted position where the advance of the holding plate is not hindered.

Further, the invention is characterized in that a holding portion for holding the film is provided below the cutter receiver, and a holding member corresponding to the holding portion is provided on the cutter side.

[0015]

Embodiments of the present invention will be described below with reference to the drawings. The stretch film packaging machine shown in FIGS. 1 and 2 is provided with a product placing portion a on which a packaged product is placed on the side of the machine frame A, and the packaged product placed on the product placing portion a is conveyed by a conveyor B. To the elevator 1 provided inside the machine frame A. A packaging portion b is provided above the elevator 1, and a side portion of the packaging portion b holds a film roll disposition portion 2 and a leading end portion of a film 3 'unwound from a film roll 3 set in the disposition portion 2. The upper and lower holding plates 11 and 9 and the holding roller 12 are provided, and the conveying means for pulling out the leading end of the film held by the upper and lower holding plates 11 and 9 by moving the holding roller 12 in close contact and conveying the film to the packaging part b The conveyor belt D as the upper and lower holding plates 1
1, a cutter E is disposed between the upper and lower holding plates 11, 9 and the conveyor belt D, and cuts the film drawn and held by the conveyor belt D to a predetermined length. Have been. Above the conveyor belt D, left and right folding plates 4 and 4 ', a rear folding plate 5, and a discharge pusher 6 located above the rear folding plate 5 are provided.

The transport belt D is composed of a transport belt D1 fixed to the reference position of the film and a transport belt D2 movable along the width of the film with the packaging portion b interposed therebetween. A pair of upper and lower endless elastic belts 42, 43 sandwiching a side end in the direction, a clamp plate 44 for pressing the lower elastic belt 43 against the upper elastic belt 42, and a starting end of the lower elastic belt 43. And a pressing belt 40 whose front end side can be freely opened and closed by a solenoid (not shown) and a spring (not shown). 45 '. The movable mounting belt 45 of the transport belt D2 is supported by two guide rods 46, 46 'arranged at right angles to the lower side thereof via connecting members 47, 47'. (Not shown) so that the film can be moved in parallel, and the film can be pre-stretched according to the depth dimension of the product.

The pair of upper and lower elastic belts 42 and 43 constituting the above-mentioned transport belt D are driven and rotated so that the film can be sandwiched and transported. The driving method is as follows. The power is transmitted by rotating the drive roller around which the roller 43 is wound, and winding the chain over a chain sprocket fixed to the shaft of the drive roller. The clamp plate 44 for pressing the elastic belt 43 is not limited to the illustrated three-division but may be divided into four or more, and such a clamp plate is left-right symmetrical with respect to substantially the center of the film so that conveyance and expansion are performed evenly. It is arranged to become.

Therefore, the object to be packaged placed on the elevator 1 is pushed up against the film 3 'stretched on the wrapping part b by the elevation of the elevator, and the end of the stretched film is After being folded into the bottom surface of the package by the left and right folding plates 4 and 4 ′ and the rear folding plate 5, the package is horizontally pushed by the discharge pusher 6 toward the discharge section in front of the machine frame A. Film 3 '
The front end of the film is folded to fold the film. In this embodiment, only one type of film roll can be mounted. However, if a plurality of film disposing sections and a transfer mechanism are provided in the frame A, a film width can be automatically switched easily.

Next, the structure of the film holding portion F will be described with reference to FIGS. The film holding unit F is located below the film 3 ′ (left side in the drawing) and is associated with an endless belt 7 that is arranged in parallel with a gap equal to or greater than the maximum width of the film 3 ′ set on the film roll 3. An upper holding plate 11 for holding the film 3 ′ supported on the surface of the lower holding plate 9 with a slight gap between the lower holding plate 9 and the lower holding plate 9, which are engaged via the attachment portion 8. And the lower holding plate 9
Roller 12 and film holding portion F attached to
And the moving means 13.

The lower holding plate 9 is a substantially rectangular flat plate, having an engaging portion 8 below the lower ends, and above the lower side, the holding roller 12 is supported by bearings 41 provided at both ends. Have been. Both ends of the lower holding plate 9 are slidably inserted into guide grooves (not shown) fixed to the machine frame. The upper end has cutouts 14 at positions corresponding to the fixed-side transport belt D1 and positions corresponding to the set positions (three locations in the present embodiment) of the movable-side transport belt D2.
Is provided so that the film is exposed.

The holding roller 12 is provided with a fixed-side conveying belt D.
The diameter of the range 15 corresponding to 1 and the range 16 corresponding to the set position (three places in the present embodiment) of the movable transfer belt D2 is a so-called stepped roller in which the diameter is large and the other portions are small. , A one-way clutch is built in so that it can rotate only in the film feeding direction. The surface of the large diameter portion is mirror-finished. The lower holding plate 9 corresponding to the large diameter portion has a through hole 18 for exposing the outer peripheral surface 17 of the holding roller. The holding roller 12 may be an independent holding roller which is divided into a range 15 and a range 16.

The endless belt 7 of the above-mentioned moving means extends over a pulley 20 fixed to a rotating shaft of a motor 19, a pulley 23 fixed to a shaft 22 of a feeding roller 21, and an idle pulley 24 provided below the cutter E. It is wound.

The upper holding plate 11 is a flat plate having substantially the same shape as the lower holding plate 9, and a notch 14 corresponding to the conveyor belts D 1 and D 2 is provided at the upper end, and is supported by the lower holding plate 9. At positions corresponding to the large diameter portions 15 and 16 of the holding roller 12, through holes 25 whose outer peripheral surfaces are exposed are formed, and as shown in FIG. 9 and 11 are adapted to move together.
A bearing 37 of a guide shaft 36 provided on the protective cover 26 is attached to the outside of the holding plate. The protective cover 26 is formed of a U-shaped plate on the upper surface and has a fulcrum 2 at the lower end.
7 allows the film to be opened outward (to the right in the drawing) integrally with the upper holding plate 9, and a recess 49 is provided between the frame and the machine frame A even when the film is closed. It is. (FIGS. 3 and 6)

Next, the configuration of the cutter and the cutter receiver will be described with reference to FIG. The cutter receiver 28 is a thin plate formed into a substantially U-shaped cross section. The cutter E enters the inside, and at the same time, the leading and trailing ends of the cut film are pushed. The length is at least longer than the maximum width of the film, and the upper surface 29 is mirror-finished to form a film temporary fixing portion 30. The film temporary fixing portion 30 facilitates the film setting operation and, at that time, presses one side of the film when cutting the film, thereby facilitating the cutting of the film. An elastic member 33 is adhered to the tip 32 of the lower surface 31, and the upper surface also serves as a guide member for guiding the film tip out of the machine frame when setting the film. Then, when the solenoid 34 fixed to the machine frame A is turned on, it advances forward against the spring 35, and when the solenoid is turned off, it returns with the urging force of the spring 35. In addition, the film temporary fixing part 3
0 may be a separate member independent of the cutter receiver 28. Further, the position may be on the cutter side (the left side of the film in the drawing).

The cutter E is a flat plate having a sawtooth-shaped tooth at its tip, and is advanced by a solenoid 38 on against a spring (not shown). Pressing and receiving members 39, 39 'for preventing the film 3' from coming into contact with the teeth when the cutter is at a fixed position are arranged above and below the cutter E. The lower press receiving member 39 comes into contact with the elastic member 33 when the cutter receiver 28 advances. (FIG. 9)

Next, the operation for setting the film 3 'in the film holding section F will be described. (1) When the film roll 3 is set in the film roll disposition section 2, the protective cover 26 is opened outward. (2) The leading end of the film 3 ′ is pulled out from the film roll 3 and is pulled up to the film temporary fixing portion 30 through the space between the upper and lower holding plates 9 and 11. (3) The leading end of the film is further pulled out, and the film 3 ′ is brought into close contact with the surface of the film temporary fixing portion 30. At this time, the leading end of the film 3 ′ is made to go out of the machine frame from the concave portion 49 in order to ensure the close contact of the film 3 ′. (4) Close the protection cover 26 and press the cutter operation switch (not shown). (5) Then, the cutter receiver 28 advances by the solenoid 34, the film 3 'is sandwiched by the elastic member 33 and the pressing receiver 39, and then the cutter E advances by the solenoid 34 to cut the film 3'. This pinching is to prevent the film 3 'from returning to the back of the holding plate due to the reaction force at the moment when the leading end of the stretched film 3' is cut. (6) When the cutting is completed, the cutter receiver 28 and the cutter E are automatically returned to their original positions by the spring, and the leading end of the excess film held by the film temporary fixing portion 30 comes out from the concave portion 49. Therefore, the film can be easily removed, thereby completing the film setting.

Next, the operation of film transfer will be described with reference to FIGS. (1) The pressing belt 40 at the tip of the transport belt is opened by the solenoid. (2) Activate the motor 19 to rotate the endless belt 7 in the counterclockwise direction, and the lower holding plate 9 engaged and the upper holding plate 11 interlocked with the lower holding plate 9 are integrally raised. .
At this time, since the film 3 'is in close contact with the holding roller 12, and the holding roller 12 can be rotated only in the film feeding direction by the one-way clutch, the film 3' is pulled out from the film roll 3 as the upper and lower holding plates 11, 9 rise. It is. Further, since the leading end of the film 3 'is held in a narrow space between the upper and lower holding plates, there is no occurrence of bending or wrinkling. (3) The motor 19 rotates by a predetermined amount, and the upper and lower holding plates 11,
When the motor 9 reaches the receiving portions of the conveyor belts D1 and D2, the motor 19 stops. (4) The solenoid is turned off, and the pressing belt 40 at the tip of the transport belts D1 and D2 returns by the force of the spring. As a result, the left and right transport belts D1, D2 sandwich the film 3 'exposed at the notch 14 opened at the corresponding position. If the conveyor belt is normally rotated forward, the leading end of the film exposed in the cutouts of the upper and lower holding plates can be cut into between the upper elastic belt 42 and the lower elastic belt 43. The need to open the tip is eliminated. (5) The transport belts D1 and D2 start rotating, and at the same time, the upper and lower holding plates 11 and 9 return to their home positions. Conveyor belt D1,
D2 is stopped when the required amount of film 3 'is paid out, and the film is cut by the operation of the cutter receiver 28 and the cutter E described above. (6) When the cutting is completed, the transport belts D1 and D2 rotate again, transport the film to the upper part of the elevator 1, and perform packaging.

[0028]

According to the stretch film packaging machine of the present invention, the following effects can be obtained by the structure described in claim 1. Since it is not necessary to hold the film when transferring the film to the conveying means, the film can be reliably fed.

According to the second aspect of the present invention, when the holding roller is started, the central portion of the film is more likely to sag than the both ends held between the left and right transport belts.
Although the slack may be wrapped around the holding roller, there is no wrapping since the film adhesion at the center of the holding roller is lower than at both ends.

According to the third and fourth aspects of the present invention, even if the central portion of the film is slack, the diameter of the central portion of the holding roller is smaller than the diameter of both ends, so that the adhesion is low. There is no involvement. Also, because of the small diameter,
The moment of inertia is reduced, and the load on the film when the film is fed or stopped can be reduced.

According to the fifth aspect of the present invention, the notch is provided in advance at each set position of the conveyor belt, so that the holding plate is changed every time the position of the conveyor belt is changed according to the change of the film width. There is no need to change the position.
Also, an adjustment mechanism for the holding plate is not required.

According to the structure described in claim 6, the film setting when a new film roll is mounted is facilitated, and anyone can work easily and quickly. Also, since the set film tip can be cut neatly, there is no need to feed it or cut it by hand in advance.

Further, according to the configuration of the seventh aspect, the cutter receiver can be retracted even if there is an object other than the film at the film cutting position, so that the cutter receiver can be used effectively.

Further, according to the configuration described in claim 8,
When cutting the film, the film is held at a position below the cutter, so that the cut end of the film can be prevented from being pulled into the back of the holding plate by a reaction force against the pulled-out force.

[Brief description of the drawings]

FIG. 1 is a vertical sectional side view schematically showing a stretch film packaging machine according to the present invention.

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

FIG. 3 is an enlarged view of a film transfer section.

FIG. 4 is a sectional view taken along line AA ′ of FIG. 3;

FIG. 5 is an enlarged view of a portion of a cutter and a cutter receiver.

FIG. 6 is an enlarged view showing a state where a protective cover is opened.

FIG. 7 is an enlarged view showing a state in which a holding plate is raised and a film is delivered to a transport belt.

FIG. 8 is an enlarged view showing a state where the cutter receiver has advanced.

FIG. 9 is an enlarged view showing a state where the cutter advances and cuts the film.

FIG. 10 is a view showing a connecting portion of an upper and lower holding plate.

[Explanation of symbols]

 D: conveyor belt E: cutter F: holding unit 9: lower holding plate 11, upper holding plate 12, holding roller 28, cutter receiver

Claims (8)

(57) [Claims] 1. A film is fed from a film roll,
The film is sandwiched between both side edges in the width direction, transported to the packaging unit and stretched, and the object to be packaged is lifted up from the lower side of the film by an elevator mechanism, and the upper surface of the object to be packaged is covered with the film. A stretch film packaging machine that folds an end of a film into the bottom surface of an article to be packaged, in a film cutting direction, a cutter that cuts a film upstream of the conveying means, and at a position upstream of the cutter, upstream of the cutter. The leading edge of the film is transported while maintaining a straight state to the transporting means, and upper and lower holding plates provided with notches at positions corresponding to the transporting means, and rotatable only in the film feeding direction and holding the film in close contact The holding roller having a possible surface treatment, and the holding plate and the holding roller are simultaneously moved so that the leading end of the film is positioned in front of the cutter. Stretch film packaging machine, characterized by comprising moving means for transferring to a position of the transfer means from. 2. The stretch film packaging machine according to claim 1, wherein the holding roller has lower adhesiveness of the film at a central portion in the axial direction than at both ends. 3. The holding roller according to claim 1, wherein a diameter at a central portion in the axial direction is smaller than both ends.
Or the stretch film packaging machine according to claim 2. 4. The stretch film packaging machine according to claim 1, wherein the holding roller is divided and disposed only near both ends in the film width direction. 5. The apparatus according to claim 1, wherein an interval between said left and right transfer means can be changed in a plurality of stages, and said upper and lower holding plates are provided with cutouts for each set position of each transfer means. The stretch film packaging machine according to any one of claims 1 to 4. 6. A supporting member for the openable and closable holding plate, wherein the upper and lower holding plates, which are closer to the outside of the main body, are openable and closable, and a guide member for guiding the leading end of the film to the outside of the main body is provided. The stretch according to any one of claims 1 to 5, wherein the installation position is on the downstream side in the film advancing direction from the position where the film is cut by the cutter when the holding plate is closed. Film wrapping machine. 7. A cutter receiver which can reciprocate between a position where the leading end of the film is cut and a retreat position where the advance of the holding plate is not hindered is provided.
The stretch film packaging machine according to any of the above. 8. The apparatus according to claim 7, further comprising a holding portion for holding the film below the cutter receiver, and a holding member corresponding to the holding portion on the cutter side.
The stretch film packaging machine as described.