JPS5815361B2 - Strap sealless joining method and device - Google Patents

Description

[Detailed description of the invention] The present invention can be operated fully automatically or semi-automatically,
A strap is then wrapped around a package such as a box, a bundle of goods, or a package and tightened with an appropriate tension, and a locking seam is formed at the overlapping portion of the wrapped strap by so-called stitching. and relates to a seal-less joining method and device for straps used primarily in automatic strapping machines (power strapping machines) which are operable to separate subsequent surplus straps from the ring of straps tied to the package. It is.

In conventional sealless joining devices, the pair of expansion links are never horizontal, even when the punch and jaw are engaged the most, i.e. at the final stage of forming the locking notch. It has a ``H'' shape, and the operation of forming the locking notch is always performed by narrowing and rising the tip of the jaw, and the punch side remains stationary.

Therefore, since the jaws are opened to a large degree when the straps are overlapped, the straps cannot be gripped, and it is therefore necessary to separately provide strap guides at the front and rear of the jaws.

Furthermore, since the upward stroke of the jaw tip is large, it is necessary to lift the strap relatively far when forming the locking notch. Therefore, excessive tension is applied to the strap, damaging the corners of the packaged items, and It had a tendency to become loose.

Regarding the positional relationship between two overlapping straps, in conventional devices, the gap between the jaws is large, so the upper and lower straps often cross each other, and the locking notch does not enter the correct position, reducing the strength of the joint. The problem was that only weak products could be obtained.

Therefore, the present inventor connected the expansion link and a yoke equipped with a punch at the lower end with a cross pin, and made the yoke vertically movable so that a locking notch is formed near the position where the expansion link becomes almost horizontal. The inventors have discovered that the above-mentioned problems can be solved by doing so, and have completed the present invention.

The first object of the present invention is to eliminate strap sealing, in which even if the front and rear strap guides are omitted, the strap overlapping portion is gripped in the proper position by a pair of jaws, and the gripping and cutting process is completed by a single actuation system. An object of the present invention is to provide a joining method and apparatus.

Another object of the present invention is to provide a seal-less joining method and device for straps that does not require lifting the straps high when forming a locking notch in two overlapping straps, thereby reducing the amount of loosening after binding. It is to provide.

Still another object of the present invention is that when tightening the strap and forming the locking notch, by aligning the sides of two overlapping straps in advance, the locking notch can be formed in the correct position. It is an object of the present invention to provide a method and device for joining straps without seals.

According to the present invention, a strap seal includes a pair of jaws that support two overlapping straps, a punch that is arranged on the upper part of the strap and can move linearly in the vertical direction, and a pair of expansion links connected to the jaws. In the welding method using a welding device without bonding, the punch and the expansion link are interlocked, and the pair of expansion links are approximately horizontal, that is, in a state where the movement of the pair of jaws is extremely small relative to the vertical movement of the punch, A method for joining straps without a seal, characterized in that a locking notch is formed in the two overlapping straps with the jaw by lowering the punch, and the two overlapping straps are supported. In a strap-less seal joining device including a pair of jaws, a punch arranged on the upper part of the strap and capable of moving linearly in the vertical direction, and a pair of expansion links connected to the jaws, the punch and the expansion link are pivotally connected. and wherein the jaw and punch are arranged to engage with each other to form a locking notch in the strap when the pair of expansion links are substantially horizontal. A bonding device is provided.

The invention will be explained in detail below by way of examples.

The strapping head 3 is in a closed loop upper position of the strap chute 4 surrounding the package 2.

First, the feed wheel 5 rotates clockwise to feed the strap 1 from the dispenser 6 into the strap chute, and when the tip of the strap goes around the strap chute and passes the jaw link mechanism 11, the rotation of the feed wheel stops and the strap 1 is fed from the dispenser 6 to the strap chute. stop supplying.

During this time, the lower strap guide 7 is closed and guides the strap on the bottom surface of the strapping head.

Next, compressed air is supplied to the rear air supply port 8B of the small cylinder 8, and the super small piston 8A advances the entire stroke of the small cylinder, pushing the large piston 9A of the large cylinder 9 forward by the stroke of the small cylinder. , the motion is orthogonally transformed by the toggle link mechanism 10 connected to the large piston, and the yoke 12 of the jaw link mechanism 11 is pushed down to close the jaw link mechanism.

A pair of jaws 15, 15 strongly grips a part near the tip of the strap to prevent the tension from being released even if the tension builds up, and at the same time holds the back surfaces of the two overlapping straps from below to prevent the strap from coming off downward.

Next, the strap guide 7 interposed between the strapping head 3 and the packaged object 2 is opened by the power of the rotating cylinder 7A and is removed from the bottom surface of the strapping head.

The feedwheel 5 then rotates counterclockwise in FIG. 2, pulling the strap through the strap chute and wrapping the strap tightly around the packaged item 2, while the strapping head 3 descends to wrap the packaged item 2. Stick to the top of something.

Next, compressed air is supplied to the rear air supply port 9B of the large cylinder 9, and the large piston 9A moves forward through the remaining full stroke.
This operation is transmitted to the jaw link mechanism through a toggle link mechanism connected to the large piston, and forms a locking notch in the two overlapping straps.

At this time, at the same time, the movable blade 18 separates subsequent surplus straps from the loop of straps tied to the package.

After completing these tasks, open the air supply port 9C of the large cylinder.
Compressed air is supplied to move the piston 9A backward.

This movement is transmitted through a toggle linkage and the jaw 1
5. Operate 15 to open each other.

The jaws 15.15 then release the binding strap that had been supported from below, and the cutters (punch 16 and movable blade 18) involved in forming the locking notch and cutting off the excess strap return to their original positions.

After this series of operations is completed, the strapping head 3
rises away from the package 2 and returns to the previously mentioned initial position, and the strap guide 7 closes again.

This completes the series of operations, but the operations of the jaw link mechanism will be explained in more detail below.

FIGS. 3 and 4 show the jaw link mechanism when feeding the straps in the initial position described above, before the jaws 15 pick up the straps 1A and 1B, and when the punch 16 is It is clear that he is retreating far above.

Figures 5 and 6 show the jaw link mechanism when tightening the straps described above, in which the upper surface 15B of the tip 15A of the jaw 15 connects the back surfaces of the overlapping straps 1A and 1B from below. Pick up the strap and release it downward.

At the same time, the lower edge 15F of the jaw strongly grips a part of the lower strap 1B between it and the shoulder 17A at the front bottom of the stationary blade 17, so that the tension does not come off even if the tension is applied. ing.

At this time, although the punch 16 has descended somewhat, its lower end cutting edge 16A is above the lower end of the guide piece 19,
It is located so as not to come into contact with the upper surface of the upper strap 1A when the strap is tightened.

FIGS. 7 and 8 illustrate the jaw linkage mechanism used to form the locking notches and cut off excess straps as described above.

That is, in FIG. 7, the lower end cutting edge 16A of the punch 16 cooperates with the tip cutting edge 15D of the tip 15A of the left and right pair of jaws 15 to form two overlapping straps 1A and 1B.
The locking notch is shown in the eighth figure.
The figure shows a state in which the tip end portion 18A of the movable blade 18 cuts the upper strap 1A between the tip end portion 17B of the stationary blade 17.

In FIGS. 3, 9, and 11, a pair of left and right jaws 15 are rotatably supported near their central portions by jaw pins 22, and move by closing and opening with the jaw pins as the center of rotation. It is fixed to the front guide frame 13 and the rear guide frame 14 so that it can be moved.

Further, three tip portions 15A are formed on the inner lower side of the jaw, and these tip portions have an upper surface 15B that supports the strap.
and a wall surface 15C and a tip end portion 15D for aligning the side surfaces of the strap.

Further, on the inner surface of the central portion of the jaw, two curved concave surfaces 15E are formed on the gap between these three tip portions, and a guide piece 19 is formed at the inner depth of each of the curved concave surfaces. is fitted into the jaw pin 22 and supported vertically and immovably.

Further, a lower end edge 15F is formed at the lower rear end of the jaw, and a round hole 15G through which a link pin passes is bored at the upper part of the jaw.

In FIGS. 3 and 10, a pair of left and right expansion links 20 have link pins 21 pivotally attached to their lower ends and are connected to link pin holes 15G of the jaws.

Further, the upper end of the expansion link 20 is connected to the lower end of the yoke 12 by a cross pin 23.

As shown in FIGS. 3 and 10, the yoke 12 is attached so as to be able to slide between a front guide frame 13 and a rear guide frame 14 whose positions are fixed with spacers 24 and bolts 25.

A cross pin 23 is pivotally attached to the lower end of the yoke, and this cross pin has three punches 16 and one movable blade 18.
The punch 16 and the movable blade 18, which are loosely pivoted and moved together with the yoke, are sandwiched between the front guide frame 13, two guide pieces 19, and the rear guide frame 14, and their positions are restricted in the space. moving, especially the guide piece 19
Since the blades guide the movement of the punch 16 in the vertical direction with their side surfaces, the relative positional relationship between the blades will not be disrupted when forming the locking cut and cutting the excess strap.

A stationary blade 17 and an upper strap guide plate 26 are attached to the lower part of the rear guide frame 14.

The technical idea of the sealless joining method and apparatus of the present invention having the above-described configuration will become clearer from the following explanation.

That is, as shown in FIGS. 5 and 6, the yoke 12
moves down a certain fixed stroke, and pushes the pair of left and right expansion links 20 apart to open them at an almost horizontal angle.

Due to the movement of this expansion link, the pair of left and right jaws 15,
15 is rotated so as to close its tip 15A and lower edge 15F, and the upper surface 15B of the tip lifts up and supports the back surfaces of the two overlapping straps from below, allowing the strap guide 7 to escape. Later on, the two straps having the same shape are held so that they do not come off downward, and the wall surface 15C following the upper surface of the tip lightly contacts the side surfaces of the two overlapping straps, so that the upper and lower Align the straps in the correct position, and further align the lower edge 15F of the jaw with the shoulder 1 of the front bottom of the stationary blade 17.
Press the lower strap 1B strongly against the strap 7A, bend it and grasp it so that the tension does not come off even if the strap is tightened.

The yoke 12 then continues down the remaining stroke, as shown in FIGS. 7 and 8.

This operation is transmitted to the jaw 15 via the cross pin 23, the expansion link 20, and the link pin 21, but since the expansion link is already opened at an almost horizontal angle, the movement of the jaw is very small and almost no movement. do not have.

In this state, only the three punches 16 and one movable blade 18 pivotally connected to the cross pin are lowered according to the stroke of the yoke, and the tip blade portions 15D of the three protrusions of the jaw and the stationary blade are lowered according to the stroke of the yoke. 17 to form a locking notch in the two overlapping straps and to cut the upper strap from the subsequent surplus strap.

During the above-mentioned operation, the jaws hardly move for the reasons mentioned above, and therefore do not further lift the strap held by the upper surface 15B of the protrusion, and also do not further lift the strap held by the upper surface 15B of the protrusion, and the wall surface 15C of the protrusion does not move the straps that have been aligned. There is no further pressing of the side surface, and the lower edge 15F of the jaw hardly moves against the shoulder 17A of the front bottom of the stationary blade 17, so that the gripped lower strap is not further damaged or bent.

In order to realize such a movement of the jaw and punch, the opening angle of the expansion link, that is, the angle θ between the line connecting the cross pin 23 and the center of the left and right link pins 21 (the center line of the expansion link) with the horizontal. The setting of the angle is very important, and it must be designed so that it is normally within ±7°, and particularly preferably within ±4°.

That is, from the position where the cross pin 23 and the left and right link pins 21 are lined up on a horizontal straight line, the cross pin moves up and down by about 3 mm each (about 6 mm in total), and the angle θ that the center line of the expansion link makes with the horizontal is usually +7. If you want to restrict the movement of the jaws, the angle should be within 14 degrees from +4 degrees.

Therefore, link lengths such as the length from the cross pin hole of the expansion link 20 to the link pin hole, the length from the jaw pin hole to the link pin hole of the jaw, and the distance between the left and right jaw pins are determined.

In the jaw link mechanism designed in this way, if the cross pin moves up and down by a total of about 6 mm, this stroke will cause the punch 16 and the movable blade 18 to form a locking notch in the two overlapping straps, and The amount of elevation is sufficient to cut the upper strap from the excess strap, and the maximum amount of movement of the tip 15A of the jaw 15 during this movement is 0.05 mm in the vertical direction and 0.05 mm in the horizontal direction.
It is only 0.9mm.

With such a small amount of movement, the desired shearing work can be accomplished without causing any practical problems in the pond.

FIG. 12 is a perspective view of a strap end in which the locking notches of a non-sealed joint of a strap formed in accordance with the embodiment shown in the drawings herein are fully mating and overlapping; the number and shape of the notches; does not necessarily have to be the same as shown in the drawings, and the technical idea of the present invention includes various sealless coupling systems with different numbers and shapes of locking notches.

Note that the punch 16 does not necessarily have to be integrated to form a cutting edge as shown in FIG.
- As described in detail in the specification of No. 162049, the punch body and the blade member are made separately, connected with a fixing pin, and the lower half of the blade part is slotted into a long thin slot to form a locking notch. Sometimes, the blade member can be made to be able to flex to increase the clearance to some extent due to shearing force, or the cutter member can be completely divided into two parts and separated, and a compression coil spring can be inserted in the middle so that the blade member can be flexed. .

All of these embodiments shown in FIG. 13 are included in the present invention.

It goes without saying that in addition to various iron bands, the strap can also be made of metal bands such as stainless steel, aluminum or aluminum alloy, brass, or plastic bands such as polypropylene, depending on the type of objects to be tied. .

The present invention is configured as described above, and has the following effects.

(1) The tip of the jaw, which also serves as a cutting edge, has the function of holding two overlapping straps when tightening the straps, so there is no need to provide a special strap holding mechanism.

(2) The wall surface of the tip end of the jaw matches the shape 2
It has the function of aligning the two straps, and the locking notches are formed in the correct position, thereby preventing variations in joint strength.

(3) When forming a locking notch in two overlapping straps, the punch side descends to form the locking notch, so the jaws do not further lift the straps, and the straps are tied together. It has the effect of reducing looseness.

(4) the jaws have the holding function, alignment function, incision forming function, and gripping function of the lower strap;
A single part serves multiple purposes.

In addition, since gripping and cutting can be performed using a single actuating system, the number of parts can be reduced, which has the effect of lowering manufacturing costs.

(5) The punch has a sturdy structure in which the three tip blades of the jaw are integrated, and the punch is designed as shown in Figure 13.

The blade has an extremely long lifespan and is effective in keeping maintenance costs low.

(6) As with the positional relationship between the guide piece 19 and the punch 16 mentioned above, the mutual positional relationship between each component is tightly regulated, so that the positional relationship between the guide piece 19 and the punch 16 is tightly regulated.

It can be operated in any position, such as horizontally or horizontally.
This has the effect of widening the scope of application to packages and equipment.

[Brief explanation of drawings]

Fig. 1 is a side view of a power strapping machine employing the device of the present invention, Fig. 2 is a cross-sectional view of the strapping head, Figs. 3 and 4 are cross-sectional views showing the state before the jaws hold the strap; 5 and 6 are cross-sectional views showing the jaws holding and aligning the two overlapping straps and gripping the lower strap;
8 and 8 are cross-sectional views showing the formation of locking notches and cutting of surplus straps, FIG. 9 is a sectional view taken along ■-■ in FIG. 3, and FIG. 10 is a cross-sectional view taken along ■-■ in FIG. 3. 11 is a perspective view of the jaw guide piece and the punch, FIG. 12 is a perspective view of the strap after joining according to the present invention, and FIG. 13 is a perspective view of another embodiment of the punch. 1... Strap, 2... Packing item, 3... Strapping head, 4... Strap chute, 5...
・Feed wheel, 6... Dispenser, 7...
Strap guide, 8... Kojigata 10... Toggle link mechanism, 11... Jaw link mechanism, 12... Yoke, 13... Front guide frame, 14...
... Rear guide frame, 15... Jaw, 16... Punch,
17... Stationary blade, 18... Movable blade, 19... Guide piece, 20... Expansion link, 21... Link pin, 2
2... Jaw pin, 23... Cross pin, 24...
・Spacer, 25... Bolt, 26... Upper strap guide.

Claims (1)

[Claims] 1. Includes a pair of jaws that support two overlapping straps, a punch that is placed above the strap and can move linearly in the vertical direction, and a pair of expansion links that are connected to the jaws. In the joining method using a strapless seal joining device, the punch and expansion link work together,
And in the vicinity where the pair of expansion links are almost horizontal, that is, in a state where the movement of the pair of jaws is extremely small with respect to the vertical movement of the punch, the punch is lowered to prevent the overlap between the pair of jaws and the jaws. A method for joining straps without a seal, characterized by forming a locking notch in two straps. 2. A strap-less joining device including a pair of jaws that support two overlapping straps, a punch that is arranged on the top of the strap and can move linearly in the vertical direction, and a pair of expansion links connected to the jaws. wherein the punch and the expansion link are pivotally connected, and the jaw and punch engage each other to form a locking notch in the strap at a position where the two pairs of expansion links are substantially horizontal. A non-seal joining device characterized in that a fixed amount is provided.