JPH08143002A - Operation controller of packaging machine - Google Patents

Abstract

PURPOSE: To stop a driving motor at a position where a rotating sealer is not in contact with a film by correcting an output pulse of a motor for driving the rotating sealer to synchronously control motors for transferring a package and the film. CONSTITUTION: When a print pitch of a film 21 carried by a motor 47 changes, a rotating sealer 29 periodically varies its speed since the sealer 29 needs to maintain speed only when it is in contact with a film 26 at an equal rate. Thus an output pulse of an encoder 34 coupled to a motor 31 for driving the rotating sealer has unequal pitches in proportion to the motor, while a pulse correcting means 36 converts the unequal pitches into equal pitches and synchronously controls a motor 46 for driving a conveyer for supplying objects to be packaged and the motor 47 for carrying the film. Therefore if an original stop position of the motor 31 when operation is stopped by a signal is determined in advance, the motor 31 can be always stopped at a position not in contact with the film 26, so that the film can be prevented from being melted due to retention heat while the sealer stops.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an operation control device for a motor that drives each operating part of a bag making and packaging machine.

[0002]

2. Description of the Related Art As shown in FIG. 4, in a general pillow packaging machine, a belt-shaped film 4 which is continuously fed by the rotation of a motor 3 is made into a tube by a tube-making means 5, while a power of the motor 1 is used. Items to be packaged 7 with a rotating conveyor 6
After being housed in the tube film 8 at equal intervals,
A pair of upper and lower rotary sealers 9 and 1 rotated by the power of the motor 2.
When 0, the tube film is cross-sealed between the objects to be packaged.

In Japanese Patent Laid-Open No. 61-259927 and Japanese Patent Laid-Open No. 62-109721, the operating speed of the first motor 1 is input to the computer 11, and the second processing function of the computer 11 is used. It is disclosed as a known example that the rotation of the third motors 2 and 3 is controlled in proportion to the rotation of the first motor 1.

In the above packaging machine, when the film 4 having a printing pitch corresponding to the length of the article 7 is changed, the origin angles of the rotary sealers 9 and 10 are automatically corrected by the computer. There is.

[0005]

Due to the above-mentioned structure, when the first motor is stopped artificially or by the automatic control of the device, the rotary sealers 9 and 10 are also driven by the first motor. It stops at the same time as the stop of 1. Since the stop position of the article to be packaged 7 on the conveyor 6 and the stop position of the rotary sealer 9 are invariable, the rotary sealers 9 and 10 often stop while being in contact with the tube film 8. There is a drawback in that the tube film 8 is melted by the retained heat of 9.

[0006]

SUMMARY OF THE INVENTION In order to eliminate the above drawbacks, the present invention provides a third motor 47 for longitudinally transporting a film that is tubed through a film, and the tube film from an inlet portion of the film. A second motor 46 for driving a conveyor for carrying the articles to be packaged therein and a first motor 31 for driving a rotary sealer for cross-sealing the tube film between the articles to be packaged are provided, and modulation of an electric signal is provided. Therefore, in the power control device of the packaging machine capable of controlling the periodic shift speed of the first motor 31,
The output pulse of the encoder 34 connected to the first motor 31 is sent to the motion control computer through pulse correction means for correcting the output pulse to an equal pitch pulse, and the second and third motors are processed by the motion control computer. The rotations of 46 and 47 are controlled in synchronization with the uniform speed rotation image of the first motor 31 corrected by the pulse correction means.

[0007]

When the print pitch of the film conveyed by the third motor is changed, the rotary sealer is required to maintain the same speed only when it is in contact with the film, so that the cyclic shift is performed. Therefore, the output pulse of the encoder connected to the first motor for driving the rotary sealer has an unequal pitch in proportion to the motor, but the pulse correcting means converts the unequal pitch into an equal pitch by calculation. The pulse signal synchronously controls the second motor for driving the article-supplying conveyor and the third motor for transporting the film.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A feeding roll 20 shown in FIG. 1 feeds a belt-shaped film 21 through a dancer roll 22 toward a former 23, and a pair of upper and lower pull belts 24, 2
5 pulls the film through the film 23 to form the strip film 21 on the tube film 26. On the other hand, when the articles to be packaged 28 are carried into the tube film 26 at equal intervals by the supply conveyor 27, a pair of upper and lower rotary sealers 29 and 30 at the rear cross-seal and cut the tube film 26 between the articles to be supplemented. To do.

In some cases, the speed of the tube film 26 may match the constant speed rotation of the rotary sealer 29, but the bag 3
When the cut pitch of 3 is changed, the weekly speed of the rotating sealer 29 and the speed of the tube film 26 are naturally different from each other.
Make sure the speeds of the two match only while they are in contact with
The servo motor 31 is adapted to rotate the sealers 29 and 30 in a cyclic shift. In this case, the encoder 34 performs velocity feedback via the controller 35, and
The cyclic shift speed of the motor 31 is stabilized as set. However, the encoder 34
Since the output pulses from are at unequal pitches, a means 36 for equalizing this pulse is used.

In FIG. 2, the time T between the a-axis and the b-axis corresponds to the time required for one rotation of the rotary sealer 29, and the time T is set to be invariable. On the other hand, the O-axis represents a state in which both speeds of the rotary sealer 29 and the tube film 26 are equal, and when the length of the packaged object changes, the rotary sealer 29 shows a curve drawn with the O-axis as a base point in the high-speed direction H or Control is performed such that a cyclic shift is performed in the low speed direction L. Therefore, most of the pulses 37 generated from the encoder 34 cannot have the same pitch. Therefore, as shown in FIG. 1, means 3 for changing the pulse generated from the encoder to a uniform pitch
6 is used. That is, since the printing pitch of the film is generally in units of centimeters rather than in units of millimeters, the cut pitch of the bag is not an innumerable unit but a countable unit. Therefore, by storing a speed program of the rotary sealer corresponding to each cut pitch in the computer, several programs 43 are stored in the storage device 38 of the computer as shown in FIG.

When the print pitch of the film used for the keyboard 40 is entered during operation, the input interface 41 matches the film speed by the selection means 42 on one side and the stored program at the other program selection means 44 from the stored program. Program 4
3 is automatically selected, and the first motor 31 cyclically shifts and rotates the rotary sealer 29 according to the selected program. On the other hand, calculation is performed so that the pulse transmitted from the encoder 34 is corrected to an equal pulse by the correction means 36, and the motion control computer 45 receives the signal from the correction means 36.
Respectively synchronizes the second motor 46, which operates the supply conveyor 24, and the third motor 47, which operates the film feeding roll 20, with the rotation of the first motor 31 by voltage modulation. In this case, in particular, the third motor 47 rotates the feeding roller 20 at a preselected film speed in synchronization with the first motor 31.

[0012]

According to the present invention, the first motor for driving the rotary sealer does not move depending on other motors, but the other motors depend on this first motor as a reference. Therefore, when the operation is stopped by the signal, if the origin stop position of the first motor is determined in advance, the first motor can be stopped at a position where it does not always come into contact with the film, and the heat held by the sealer can be used during the stop. It is possible to prevent the film from melting.

[Brief description of drawings]

[Figure 1] Side view

FIG. 2 is an explanatory diagram of a cyclic shift value of a sealer.

FIG. 3 is a block diagram of control means.

FIG. 4 is an explanatory diagram of a conventional example.

[Explanation of symbols]

31 ... 1st motor 34 ... Encoder 36 ... Equal pitch pulse generating means 38 ... Storage device 45 ... Exercise computer 46 ... Second motor 47 ... Third motor.

Claims (1)

[Claims] 1. A third motor 47 for longitudinally transporting a film that is tubed through a film, and a second motor 46 for driving a conveyor that carries an article to be packaged into the tube film from an inlet portion of the filmer. , A first motor 31 for driving a rotary sealer that cross-seals the tube film between each of the objects to be packaged, and the periodic shift speed of the first motor 31 can be controlled by modulating an electric signal. In a power control device for a packaging machine, the output pulse of the encoder 34 connected to the first motor 31 is sent to a motion control computer through pulse correction means for correcting the output pulse to an equal pitch pulse by a processing signal from the motion control computer. The first motor in which the rotations of the second and third motors 46 and 47 are corrected by the pulse correction means. An operation control device that is controlled in synchronism with the image of the uniform speed rotation of 31.