JPH0138013Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention involves inserting a pair of spatula plates into the opening of a packaging bag, and displacing both of these plates in both directions to create an opening of the bag. Relating to a device for tensioning edges. However, this application is based on the earlier application filed by Jitsugan Sho.
This is an improvement of 59-6042.

(Prior art) For example, when welding the bag opening by compressing the bag opening between a pair of heat bars, if the bag opening is loose, the bag opening will be welded with wrinkles.
As shown in FIGS. 3 and 4, spatula plates 2, 2 inserted into the mouth of the bag 1 are extended in opposite directions to tension the bag mouth before welding (Japanese Patent Application Laid-open No. 57-37528). Also, when a large number of stacked packaging bags are taken out one by one from the top, a pair of spatula plates inserted into the bag opening tensions the bag opening, and the bag is transported while being supported by these spatula plates.

(Problems to be solved by the invention, etc.) However, as shown in Figures 3 and 4, for example, when the bag has a swollen abdomen due to the contents being packed inside the bag, the bag opening tends to twist. Therefore, when the pair of spatula plates 2, 2 are extended symmetrically, the folds 3, 3 on both sides of the bag are twisted and tensioned, and the bag opening is welded by the seal bar in this state. It was hot.

Also, when taking out stacked packaging bags one by one using a spatula plate, if the packaging bags are placed in a state where they have slipped sideways, the spatula plate 2 on one side may Since the bag is stretched in advance of the spatula plate 3 on the other side, the bag becomes twisted, and when the bag is transported in this state to a packaging machine, there is a drawback that the bag is clamped in a twisted state in the packaging machine.

In view of the above points, the present invention provides a device that tensions the bag without twisting it even if there is some misalignment between the spatula plates and the center of the packaging bag.

(Means for Solving the Problem) In order to achieve the above object, the present invention rotatably supports a pair of bag expansion blocks with respect to a frame at a constant interval through pins, and The interlocking mechanisms at opposite ends of both bag expanding blocks are engaged so that both bag expanding blocks interlock in symmetrical movement with the bag expanding block as an axis, and the bag expanding block is connected to one side of the bag expanding block with the pin. A power mechanism is connected to the power mechanism that rotates the bag around the axis, and a leaf spring is provided at the tip of each of the bag expansion blocks, the spring function of which works in the direction of expanding the bag mouth, and a bag mouth tensioning mechanism is provided at the tip of each of these leaf springs. It is equipped with a spatula board.

(Function) When a pair of bag expansion blocks are rotated, a pair of spatula plates provided on both bag expansion blocks are spread in opposite directions, and the bag opening is tensioned with these spatula plates, if one side spatula plate is Even if the spatula on the other side contacts the inner surface of the bag opening earlier than the spatula plate on the other side, due to the cushioning properties of the leaf spring that supports the spatula plate, no force is applied to the bag opening, and the spatula on the other side that contacts the bag opening later Since it works together with the board to tension the bag opening, the bag opening is tensioned without twisting.

(Example) Examples of the present invention will be described below based on the drawings.

As shown in FIGS. 1 and 2, a pair of rectangular bar-shaped bag expansion blocks 11, 11 are attached to the upper surface of an elongated frame 10 which is horizontally arranged.
2 and 12, and an interlocking mechanism 25 is provided on the upper surface of these bag expansion blocks so that the blocks move symmetrically. The interlocking mechanism has screws 3 on the upper surfaces of both blocks 11, 11.
It consists of two links 13 and 14 fixed at 0 and 30, and a slit 15 formed at the end of one link 13 is engaged with a pin 16 provided at the end of the other link 14. On the other hand, an air cylinder 17 fixed to the base of the frame and the bag expansion block 11 on one side are connected via a piston rod 18, and the pair of bag expansion blocks 11, 11 are moved by the power of the air cylinder 17. Even symmetrical movements seem to work together. Further, the spatula plates 20, 20 are attached to the opposing surfaces of the tip ends of both the bag expansion blocks 11, 11 via the plate springs 21, 21, respectively, with the screws 2.
It is fixed at 2,22.

In addition, in the embodiment, the leaf springs 21, 21 and the spatula plate 2
0 and 20 are made of the same material. That is, the tip of the band-shaped leaf spring 21 is twisted and then bent downward. Further, in the figure, reference numeral 28 denotes an arm that supports the frame 10 on a machine stand 29, and the arm 28 moves the frame 10 up and down using power transmitted from a shaft 30 at one end.

When fluid pressure is applied within the air cylinder 17 and the piston rod 18 is reciprocated, the frame 10
A pair of bag expansion blocks 11, 11 supported by and engaged by an interlocking mechanism 25 are each supported by a pin 1.
2 and 12 as axes, and causes the spatula plates 20 and 20 fixed by screws 22 and 22 to approach and separate. For this reason, in FIG. 1, the mouth of bag A is covered with both spatula plates 20, 20,
By separating 20, the mouth of bag A becomes tense. In this case, since the bag swells with the contents and the bag opening is twisted, there is a tendency for the spatula plate on one side to come into contact with bag A first. Assuming that the left spatula plate 20 contacts bag A first,
Due to the cushioning of the leaf spring 21, the left leaf spring 21a moves inward as shown by the imaginary line 21a, and later the right spatula plate 20 comes into contact with the bag A, and the piston 17 causes both spatula plates 20, 20 to move inward. As a result of further widening the gap, the bag opening is tensed in both directions by the reaction force of the leaf springs 21, 21. In this way, both spatula plates 20,
20, there is a delay in contact with the bag, but due to the cushioning of the leaf springs 21, 21, the spatula plate does not force the bag only in one direction, and as a result, the bag is stretched in both directions almost simultaneously. This prevents the bag from twisting.

In the embodiment, the bag expansion blocks 11, 11 are configured to be interlocked by the engagement between the slit 15 and the pin 16, but in general, this type of block is interlocked by the engagement of a pair of gears. Many things are done by Therefore, the power mechanism may be one that directly transmits rotational power to the shaft 12, instead of one that reciprocates like the air cylinder 17.

(Effects) As mentioned above, the bag tensioning device of the present invention does not directly operate a pair of spatula plates in opposite directions using a power mechanism to tension the bag opening, but instead operates each spatula plate on the bag expansion block. In addition to being fixed via a leaf spring, the spatula plates are actuated in opposite directions via a bag expansion block to tension the bag opening. Even if there is contact, the bag is not forced to be pulled in only one direction due to the cushioning of the leaf spring, and the bag opening can be symmetrically extended in both directions and tensioned without twisting.

[Brief explanation of the drawing]

FIG. 1 is a plan view showing an embodiment of the present invention, FIG. 2 is a cross-sectional view taken along the line --, FIG. 3 is an explanatory diagram of a conventional example, and FIG. 4 is a plan view of the previous figure. 10... Frame, 11... Expanding bag block, 1
7... Air cylinder (power mechanism), 20... Spatula plate, 21... Leaf spring, 25... Interlocking mechanism, A...
bag.

Claims (1)

[Scope of utility model registration request] A pair of bag expansion blocks 1 for the frame 10
1 and 11 at a fixed interval and connect them to pin 1, respectively.
The pin 1 is rotatably supported via pins 2 and 12.
The interlocking mechanisms 25 at opposite ends of both bag expansion blocks are engaged so that the bag expansion blocks 11 and 11 interlock with each other in a symmetrical motion with 2 and 12 as axes, and the interlocking mechanism 25 is engaged with the bag expansion block on one side. A power mechanism 17 is connected to rotate the bag expansion block around the pin 12, and leaf springs 21, 21 are provided at the ends of both bag expansion blocks 11, 11, respectively, so that the spring function acts in the direction of expanding the bag opening. In addition, a bag tensioning device is provided with spatula plates 20, 20 for tensioning the bag opening at the tips of each of these leaf springs.