JPS6050643B2 - Film side holding device for packaging machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a film side holding device for a packaging machine that wraps products with stretch film.

Conventionally, in this type of packaging machine, when the film is folded onto the bottom surface of a product by pinching the sides of the film, the top surface is stretched under tension.

Moreover, there are multiple types of film with different widths depending on the size of the product, and the interval between the film holders that clamp the sides of the film must be set each time depending on the width of the film used. It is something that exists. Therefore, it is necessary to adjust the position of the film holder each time the film is changed, and the preparation work is extremely troublesome. Further, it is desirable to pre-stretch the film by pulling it on both sides before wrapping the wrapping device, but in the prior art, this pre-stretching is performed by another mechanism, and the device is complicated. The present invention has been made in view of the above points, and an object of the present invention is to provide a film side holding device for a packaging machine that can simultaneously achieve adaptability to film width and a pre-stretch function. be.

An embodiment of the present invention will be described based on the drawings.

First, the overall structure will be explained with reference to FIG. A protruding part 2 is formed on the front surface of the main body case 1, and a carry-in part 4 is provided from the protruding part 2 to the middle part of the main body case 1, into which a product 3 to be packaged is fed. A lift 5 is provided at the tip of the carry-in section 4 and is connected to a drive section (not shown) to move up and down. A plate-shaped stopper 6 is provided at the rear of the lift 5 in a fixed position, and a slide plate that reciprocates in the horizontal direction between the lower edge of the stopper 6 and the upper surface of the lift 5 at the lowest position. 7 is provided. Next, at the rear of the main body case 1, there is provided a roll body holding section 10 that rotatably holds two roll bodies 9 each having a film 8 wound therein in a vertical position. The film 8 that has been pulled out is guided by a plurality of guide rollers 11 and drawn into the main body case 1, and the leading end of the film 8 is held by a film holding section 12.

One of these two films 8 is selectively used. Further, a support shaft 13 is provided below the film holding section 12, and a receiving plate 14 provided above.
A presser body 15 is rotatably provided on the spindle 13 and presses the film 8 pulled out as described later between the presser body 15 and the film holder 12. A cutter 16 for cutting the film 8 is rotatably provided on the support shaft 13.

Next, a film feeder 17 is provided in substantially the same horizontal plane as the film holder 12 and is movable in a reciprocating manner, gripping the tip of the film 8 and drawing it out toward the front. Film holding body 18 to grip
is provided.

A front folding body 19 and a left and right folding body 20 are provided in an overlapping manner, and the front folding body 19 and the left and right folding bodies 20 move horizontally reciprocally along the bottom surface of the product 3 which is pushed up while stretching the film 8 by the lift 5, and the upper part thereof is provided with a packaging material. A carry-out belt 21 is provided to contact the top surface of the product 3 and move it backward, and a guide belt 22 is provided at the rear and lower part of the carry-out belt 21. A transfer belt 23 is provided connected to the guide belt 22, and a heat seal plate 24 for heat sealing the folded film 8 is provided between the transfer belts 23.
After such a transfer belt 23! A roller 23a is provided at the end to transfer the packaged product 3 to another mechanism.
Next, details of the film holding body 18 portion will be explained.

First, a threaded rod 27 whose left and right threaded portions have a lead angle of 5 in opposite directions is rotatably held in a frame 26 with a support plate 25 provided in the middle, and two ball shafts 28 are parallel to this threaded rod 27. is fixed. Two plates 29 are provided facing each other and are screwed onto the threaded rod 27 and fitted onto the ball shaft 28 so as to be slidable in the axial direction. Film holding body 18
is installed. A pair of clamping claws 30 for clamping and releasing the sides of the film 8 are provided inside the upper ends of these film clamping bodies 18. In addition, the screw rod 27
A gear 31 is fixed to the gear 31, and a gear 32 rotatably attached to the ball shaft 28 is meshed with the gear 31. A sprocket wheel 33, which is integral with the gear 32, is attached to a drive shaft 34. sprocket wheels 35 are connected via a chain 36. Another sprocket wheel 37 is fixed to the drive shaft 34 and connected to a sprocket wheel 40 of a movement amount control mechanism 39 through a chain 38 . The operation amount control mechanism 39 is configured as follows.

That is, a first cam 42, a second cam 3 and a third cam 44 are fixed to a cam shaft 41 connected to a drive section (not shown),
The drive shaft 34 is rotatably attached to the camshaft 41. The first cam 42 has a film width of, for example, 350T! Corresponding to Rln, the second cam 43 is 40
Corresponding to h, the third cam 44 is 450? shall correspond to Next, a support shaft 45 is provided parallel to the camshaft 41, and a cylindrical shaft 46 is rotatably provided on this support shaft 45.

The sprocket wheel 40 is attached to one end of this cylindrical shaft 46.
is fixed thereto, and a first lever 48 biased by a tension spring 47 so as to be connected to the first cam 42 is fixed to the other end. The following parts are sequentially provided on the outer periphery of the cylindrical shaft 46 and located between the first lever 48 and the sprocket wheel 40. First, the first lever 48
The tension spring 4 is connected to the second cam 43 from the side.
A second lever 50 biased at 9 is rotatably mounted, a solenoid lever 51 and a solenoid lever 52 are fixed, and a tension spring 5 is attached so as to be connected to the third cam 44.
A third lever 53 biased by 3a is rotatably attached. The solenoid lever 51 is driven by a solenoid 54 to open the hole 5 of the second lever 50.
A pin 56 is provided which is fitted into and integrated with 5. The solenoid lever 52 also includes a solenoid 5.
A pin 59 is provided which is driven by the lever 7 and fitted into the hole 58 of the third lever 53 to be integrated with the third lever 53. Next, regarding the electrical connection, a film width setting switch 61 is connected to a timing switch 60 that turns ON and OFF in synchronization with the feeding of the film 8, and a terminal a of this film width setting switch 61 is directly connected to a power supply E. A solenoid 54 is connected to terminal b, and a solenoid 57 is connected to terminal C.

In such a configuration, the general operation from when the product 3 is carried in, wrapped with the film 8, and carried out will be first explained.

Here, the products 3 are food items etc. stored in a tray with an upward opening, and the products 3 are sequentially fed onto the carry-in section 4 by an operator. The product 3 is sent onto the lift 5 by this carry-in section 4. First, as shown in FIG. Slide plate 7 as shown in the figure
When the product 3 is retracted, the product 3 is placed on the lift 5 with its position and direction determined by the stopper 6. At the same time, the film feeder 17 advances rearward at the timing shown in FIG. 2 and grips the film 8 slightly protruding from the film holder 12, and at the timing shown in FIG. 3, the film feeder 17 moves forward. to feed out the film 8, the film holding body 18 grips both sides of the film 8, the presser body 15 rotates and holds the film 8 between it and the receiving plate 14,
The cutter 16 operates to cut the film 8 to a predetermined size. The detailed operation of the film holder 18 at this time will be described later. Next, as shown in FIG. 4, the lift 5 rises and pushes up the stretched film 8 from below to position the top surface of the product 3 directly below the delivery belt 21, and the front folding body 19 moves backward and the left and right folding bodies move backward. 20 is simultaneously moved towards the center so that the front and side parts of the film 8 are folded onto the bottom of the article 3.

At this time, the film 8 is released from being gripped by the film feeder 17 and the left and right pressers 18. When the front folding body 19 and the left and right folding bodies 20 enter the lower part of the product 3 in this way, the product 3 is lifted above the top surface of the lift 5, and the top surface of the product 3 is joined to the carry-out belt 21. be done. Therefore, as shown in FIG.
The rear part of the product 3 is folded into the bottom surface of the product 3 by the guide belt 22 and discharged onto the transfer belt 23 by the carry-out belt 21.
The folded film 8 is welded on the heat seal plate 24 and conveyed to the required position via the rollers 23a. Next, the detailed operation of the film holder 18 will be explained.

First, since the width of the film 8 to be used is determined in advance, the film width setting switch 61 is operated accordingly. The film width is now 3507077! If so, the solenoids 54 and 57 are not energized, the second lever 50 and the third lever 53 are in a free state with respect to the cylinder shaft 46, and the second cam 43 and the third cam 44 are not energized. Not involved in the action. Therefore, when the camshaft 41 rotates,
The first lever 48 is rotated by the first cam 42 against the tension spring 47, and the sprocket wheel 4
Rotate 0. Then, the threaded rod 27 rotates via the chain 38, sprocket wheels 37, 35, chain 36, sprocket wheel 33, and gears 32, 31, and as a result, the plate 29 holding the film holder 18 moves toward the center. It stops when the distance between the two reaches 35h. Then, a voltage is applied to a drive source (not shown) that drives the clamping claws 30 to clamp both sides of the film 8.
Next, the first lever 48 is rotated back by the force of the tension spring 47 based on the shape of the first cam 42, and the film holding body 18 is rotated.
A pre-stretching process is performed in which the film 8 is moved outward to generate tension in the film 8. Then, as the packaging process progresses, the clamping claws 30 are released, and the first lever 48 is rotated back by the force of the tension spring 47 to return the film clamping body 18 to its original position. Next, set the film width setting switch 61 to 400w! When the timing switch 60 is turned ON, the solenoid 54 is energized, the pin 56 fits into the hole 55, and the second lever 50 is integrated with the cylinder shaft 46.

As a result, the second lever 50 is operated by the second cam 43, and operates as described above. At this time, the first cam 42
is smaller than the second cam 43, so the first lever 48 does not participate in its operation at all. Therefore, the film holding body 1
8 becomes 40-spacing, and after pre-stretching the film 8
Release and return. Also, the width of film 8 is 45
When it reaches 0w$t, the third lever 56 comes into operation.

As described above, the present invention sets the film holders at the reference position with a large gap between them, narrows the gap between the film holders to the film width set by the film width setting switch, and then pinches the film. The film holder moves to perform pre-stretching and returns to its original position after releasing the film, so by simply pressing the film width setting switch to match the film being used before work, the film holder can be adapted to accommodate multiple film widths. At the same time, the film can be pre-stretched using the film holder, which greatly improves operability and simplifies the structure.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, and FIGS. 1 to 5 are longitudinal sectional side views showing the packaging process, FIG. 6 is a perspective view of the main part, and FIG. 7 is a sectional view of a part thereof. FIG. 8 is a front view showing the shape of the cam, and FIG. 9 is an electric circuit diagram. 3...Product, 8...Film, 18...
...Film holding body, 27...Screw rod, 34...
... Drive shaft, 39 ... Operation amount control mechanism, 42
...First cam, 43...Second cam, 44.
...Third cam, 48...First lever, 5
0...Second lever, 53...Third lever, 61...Film width setting switch.

Claims (1)

[Claims] 1. A film clamping body that clamps the side of the film is connected to a screw rod that moves toward or away from each other by rotating forward and backward, and a drive shaft is connected to this screw rod,
A set of cams corresponding to the number of types of films of different widths to be used and a lever driven by the cam are provided, and the lever is biased in a direction to widen the gap between the film holding bodies to drive the film. The selected cam is connected to the shaft, and the selected cam is rotated to rotate the lever corresponding to the cam, and the rotation angle of this lever sets the proximity position of the film holding body, and also controls the relationship between the cam and the lever. 1. A film side holding device for a packaging machine, characterized in that a motion amount control mechanism is provided for releasing the engagement and expanding the film holding body by the biasing force of the lever.