JPS596768B2 - Packing machine tape feed tension device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device for tightening a fed thermoplastic tape in an automatic packaging machine.

Packing machines that wrap a thermoplastic tape such as polypropylene around the outer circumference of the packaged item, tighten the packaged item with this tape, and weld both ends of the tape that correspond to the top and bottom using heat and pressure are widely used. It is used.

In the above-mentioned packing machine, when packing is completed, the tape is fed out a predetermined length in preparation for the next packing, and during the packing operation, a tightening step is performed to pull back the tape and tension it.

Generally, the tape is fed and tightened by rotating rollers that constantly sandwich the tape from both sides. The synthetic resin tape used for packaging is flexible and relatively weak.

For this reason, if the tape is fed by inserting the tip of the tape between the rollers that are in constant pressure contact, or if the feeding process is performed with the tape being held by the rollers with strong force, the tape may bend. There is a problem in that D wrinkles occur and the tape becomes clogged in the tape feeding and tensioning device, especially between the front and rear rollers, which hinders the packaging work.

This invention was made in order to solve the above-mentioned problems, and during the tape feeding process, the tape moving roller and the tape tightening pressure roller are separated to release the tape grip. It is an object of the present invention to provide a feeding tightening device that does not cause tape trouble during the feeding process.

Embodiments of the present invention will be described below with reference to the accompanying drawings.

Fig. 1 shows the main mechanism of an automatic packing machine, in which a main body 1 is fixed in a case in which a packaged item A is placed, and a guide 2 supports the main body 1 so that it can be moved freely. A guide plate 4 is attached to the lower part of the slide plate 3, which is movable in the same direction as the slide plate 3, with a slight gap provided at the bottom of the slide plate 3.

A camshaft 5 driven by a motor M1 is mounted horizontally on the main body 1 at a lower position supported by a bearing. , a clamp 6 that is movable up and down, a pressurizer 7 that is also movable up and down, a cutter lower blade 8 fixed at a fixed position to cut the tape B in the middle, and the lower blade 8 to cut the tape B. A cutter blade 10 is rotatably attached to cut the tape, and has a slide plate 3 at its tip and a clamp part 9 for clamping the tape B. A freely provided cutter rod 11,
A spring 12 is arranged side by side to give the upper blade 10 rotational elasticity in a direction in which the tip thereof rises.

Although not shown, a welding heater is provided between the slide plate 3 and the pressurizer 7, which appears and disappears after the guide plate 4 leaves work.

The camshaft 5 includes:
A cam 13 that moves the clamp 6 up and down by the rotation of the camshaft 5, a cam 14 that moves the welding heater in and out, a cam 15 that moves the pressurizer 7 up and down, and a cam 16 that moves the slide plate 3. Cams 17 for moving the rod 11 up and down in order to rotate the cutter's upper blade 10 are installed in such a way that they are moved forward and backward at the same timing. A feeding tensioning device (hereinafter referred to as tensioning device 3) 21 for feeding and tightening the tape B is attached to the left side portion of the main body 1 in FIG.

The tightening device 21 includes a tape moving roller 22 rotatably attached to the main body 1, a tape tightening press roller 23 that moves forward and backward with respect to the roller 22, and a tape tightening roller 23 that moves the tape B4q more than the roller 23. It is comprised of a tape pressing roller 24 located at the front in the drawing direction and always in pressure contact with the moving roller 22, and an advancing/retracting mechanism 25 that moves the tape tightening pressing roller 23. The table moving roller 22 is interlocked with the motor M2 via a rotation transmission means, and is rotated in the forward and reverse directions of the motor M2 in the forwarding direction of the tape B (counterclockwise direction in FIG. 1) and in the tightening direction of the tape B. (clockwise in Figure 1) rotation is applied.

The tape tightening press roller 23 is attached to a support fitting 26 disposed on the left side of the tape moving roller 22 in FIG. 1 so as to freely rotate around a shaft 27. Support metal fittings 26
is vertically long, and its upper end is pivotally fixed by a pin 28 at a position above the moving roller 22 of the main body 1, and is attached in a suspended state so as to be able to swing freely around this pin 28.

The tape tightening press roller 23 is attached near the upper end of the support fitting 26 and is arranged to be at approximately the same height as the tape moving roller 22 . I will be joining and retiring from work.

The tape B pulled out from the reel enters between the tape moving roller 22 and the tape tightening presser roller 23 from below, bends along the outer periphery of the tape moving roller 22, and then passes through the presser roller 24. The tape passes through the tape guide 29 provided between the tape moving roller 22 and the upper cutter blade 10, and is fed out toward the lower part of the slide plate 3.

Only when the tape moving roller 22 rotates in the tape tightening direction, the tape tightening presser roller 23 approaches the tape moving roller 22 by an advancing/retracting mechanism 25 (described later), clamps the tape B, and performs the tightening process. During the tightening process, it is separated from the tape moving roller 22 to form a gap 30 between it and the tape moving roller 22 through which the tape B can freely pass, as shown in FIG. are doing.

The tape pressing roller 24 is attached to the pin 28 of the support fitting 26.
It is attached to the tip of a swinging arm 31 which is pivoted so that it can swing freely. The tape pressing roller 24 is located directly above and in parallel with the tape moving roller 22, and is given elasticity in the direction of constant pressure contact with the moving roller 22 by the pressing force of a spring 32 provided on the swing arm 31. The tape B is constantly pinched by the moving rollers 22.

The advancing/retracting mechanism 25 that swings the tape tightening press roller 23 is pivoted at a position corresponding to the cam 33 by a cam 33 fixed to the end of the camshaft 5 and the lower end of the support fitting 26. It is comprised of a roller 34 and a tightening strength adjusting means 35 that imparts rotational elasticity to the support fitting 26 so that the tape tightening presser roller 23 is always in pressure contact with the tape moving roller 22. The cam 33 pushes the roller 34 with its protrusion 33a, holds the tape tightening pressure roller 23 in a position where the gap 30 is formed, and also presses the roller 34 during the tightening process.
4 falls into the lower part 33b, the tape tightening presser roller 2
3 to approach the moving roller 22.

The adjustment means 35 includes a screw shaft 36 pivotally fixed to the main body 1 so as to pass through the lower part of the support fitting 26, an adjustment screw 37 screwed into the tip of the screw shaft 36, and an adjustment screw 37 fitted onto the screw shaft 36,
It is composed of a spring 38 compressed between the adjustment screw 37 and the support fitting 26, and by changing the screwing position of the adjustment screw 37 and changing the repulsive elasticity of the spring 38, the pressure roller 23 for tightening the lice can be adjusted. The tape clamping force, that is, the tape tightening force can be selected.

Note that the tape guide 29 can swing freely around a pivot 39, and when the tape B is under tension, the rotation of this guide 39 is used to detect the tension of the tape and drive a motor M1 near the guide 27. and a changeover switch S for controlling M2.

The tightening device of the present invention has the above-mentioned structure, and the packing method will be explained next.

The tape tightening presser roller 23 is used in the second
As shown in the figure, in the open position, a gap 30 is formed between the tape moving roller 22 and the tape pressing roller 24.
is constantly pressed against the moving roller 22 by the pressure of the spring 32.

To arrange the tape B taken from the reel along the tape line, insert the tip of the tape B through the gap 30 to the position of the presser roller 24, and rotate the motor M2 in the feeding direction. The tape B is fed onto the slide plate 3 from within the tape guide 29 while being lightly sandwiched between the tape moving roller 22 and the presser roller 24.

A predetermined length of feed is obtained by using a timer or the like. Next, normal packing work will be explained.

As shown in FIG. 1, when the start switch is pressed with the tip of the tape B wrapped around the outer periphery of the package A inserted between the guide plate 3 and the guide plate 4, both motors MlM2 are energized at the same time.

First, when the camshaft 5 is slightly rotated by the motor M1, the cam 17 is lowered by the rod 11, and the tip of the upper cutter blade 10 is rotated upward by the pulldown of the spring 12, and the clamp portion 9 at the tip is lowered. The slide plate 3 clamps the middle of the insertion side of the tape B to prevent it from coming out.

Next, when the motor M2 is activated in the tightening direction, the tape moving roller 22 rotates in the tightening direction clockwise in FIG.

At this time, since the presser rollers 24 are holding the tape B, the tape B starts to be tightened, and the tape B is pulled back toward the reel with a weak force, and the portion wound around the packaged item A becomes tense. The cam 3 is rotated by the rotation of the camshaft 5 by the motor M1.
3 faces the roller 34, and when the roller 34 falls into this low portion, the motor M1 temporarily stops, and as shown in FIG. Press the tape B against the tape moving roller 22.

Therefore, the moving roller 22 rotating in the tightening direction and the tape tightening press roller 23 pinch the tape B with a strong force, so that the tape B is fully tightened. When tape B reaches a predetermined tension, switch S detects this and motor M2
The motor M1 is then energized again to rotate the camshaft 5.

When the camshaft 5 rotates, each cam attached to the camshaft moves the guide plate 4 first, then the clamp 6 rises, and the overlapping portion of the tape B is simultaneously moved with the slide plate 3. The tape B is held in a tensioned state by being pinched, and the upper cutter blade 10 then rotates downward to cut the tape B in the middle with the lower cutter blade 8.

At the same time, a heater is inserted between the upper and lower tapes,
The pressurizer 7 rises and pushes up the cut surface of the tape B, and the heater is sandwiched between the upper and lower tapes to melt the upper and lower corresponding surfaces of the tape.

After melting the tape, the heater is pulled out and the pressurizer 7 continues to press, so that the upper and lower tapes are welded under pressure.

When welding is completed, the pressurizer 7 is lowered, and then the clamp 6
Since the slide plate 3 is pulled out from between the tape and the packaged item A, the packaged item A can be removed.

When it becomes possible to remove the packaged item A, the slide plate 3 returns to its original position (b), the roller 34 is pushed by the protrusion 33a of the cam 33, and the tightening presser roller 23 moves to the open position shown in FIG. , when the camshaft 5 reaches just before one rotation, the tape feeding process begins. In the feeding process, the motor M2 is energized and the b1 tape moving roller 22 is rotated in the tape feeding direction, so the tape B is fed by the tape moving roller 22 and the presser roller 24, and with one rotation of the camshaft 5, Motor M
1 and M2 are stopped and prepared for the next packing.

As described above, according to the present invention, the tape tensioning pressure roller, which tightens the tape by pinching the tape with the tape movement roller, is operated using a cam attached to a camshaft and a pressure spring, and the tape is moved. The tape tensioning presser roller can move forward and backward relative to the roller, and the tape tensioning presser roller can be separated from the tape moving roller except during the tensioning process. When sending out the tape, the pressure rollers for tightening the tape do not act on the tape at all, so there is no problem of the tape getting stuck between the rollers, causing creases, and the packing operation can be carried out smoothly. It has the effect of becoming like this.

In addition, since the pressure roller for tape tightening is operated by a cam,
A strong elastic spring can be used to press the presser roller against the moving roller, and the tape can be tightened firmly.

[Brief explanation of drawings]

Fig. 1 is a front view showing the state in which the tensioning device according to the present invention is used, Fig. 2 is an enlarged sectional view showing the main part of the same during the tape feeding process, and Fig. 3 also shows the state during the tape tensioning process. FIG. 21...Tightening device, 22...Tape moving roller,
23... Tape tightening press roller, 24... Tape press roller, 25... Advance/retreat mechanism, 26... Support metal fittings, 30... Gap, 31... Swinging arm, 32, 38
...Spring, 33...Cam, 34...Roller, 35
...Adjustment means.

Claims (1)

[Claims] 1. A tape moving roller that rotates in both the feeding direction and the tape tightening direction, and a tape that is provided at a position where the tape is narrowed by the outer periphery of the moving roller and is provided with elasticity so as to be in constant pressure contact with the moving roller. A tape tightening press roller, which is provided so as to narrow the tape between a press roller and the outer periphery of a tape moving roller at a position in the tape tightening direction relative to the tape press roller, and is attached to the tape moving roller and can freely move forward and backward. In the tape tensioning device, the tape tensioning presser roller is attached to a support fitting that can swing freely around a pin located above the presser roller, so that it can freely rotate. A swinging cam of a support fitting is attached to a camshaft arranged to rotate at a position lower than the tape tensioning pressure roller on one side of the swinging direction, and a roller is attached to the support fitting at a position corresponding to the cam; A spring is provided on the support fitting to apply elasticity toward the cam so that this roller is always in pressure contact with the cam, and the cam pushes the support fitting during the tape feeding process to separate the tape tensioning presser roller from the moving roller. 1. A tape feeding and tightening device for a packaging machine, comprising a protrusion and a lower portion that releases pressure from a support fitting during a tape tightening process and presses a tape tightening presser roller against a moving roller.