JPH0825542B2 - Horizontal seal control method and apparatus for vertical bag-making filling and packaging machine - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vertical bag-making filling and packaging machine capable of suitably controlling the opening and closing position and speed of the horizontal sealer and the lateral seal pressure according to the packaging speed. The present invention relates to a control method and its device.

[0002]

2. Description of the Related Art A packaging film fed from an original roll is formed into a tubular shape by a bag making machine, the tubular film is fed vertically downward, and a vertical seal is applied to its superposed edge portion.
2. Description of the Related Art A vertical bag making / filling / packing machine for obtaining a so-called pillow package by horizontally sealing / cutting the upper and lower positions of an article to be packaged which is dropped and supplied to the cylindrical film is widely used in various industrial fields. The present invention relates to the control of the horizontal sealing mechanism used in this vertical bag-making filling and packaging machine. Therefore, in order to contribute to the understanding of the invention, a schematic configuration of the packaging machine will first be described. As shown in FIG. 6, the film 12 from the original roll 10 is intermittently delivered by a pair of delivery rollers 14, 14 and passes through a dancer roller 16 and a guide roller 18 to form the bag making machine 2.
It is fed toward 0. The bag making device 20 is concentrically arranged with the hollow mandrel 22 arranged upright, and the film 12 is formed into a tubular shape when passing through the bag making device 20. The cylindrically formed film 12 is intermittently fed downward along the outer periphery of the mandrel 22 by the feed belts 24, 24 arranged to face the outside of the mandrel 22. The edge portions of the tubular film 12 overlapping in the longitudinal direction are fed downward by the vertical sealers 26, 26 which are driven to open and close at required timing by an appropriate drive source (not shown). A vertical seal is applied during the suspension of the film feeding.

A hopper 30 into which various kinds of articles to be packaged 28 are loaded is arranged immediately above the bag making machine 20, and the mandrel 22 located below and the axis thereof are aligned. Above the hopper 30, a supply device (not shown) for dropping and supplying the article to be packaged 28 at a required timing is provided.
Below the mandrel 22, a pair of horizontal sealers 32, 32 are arranged so as to be horizontally movable so as to sandwich the vertical feeding path of the tubular film 12, and a packaged object 28 supplied to the tubular film 12 is provided. Lateral sealing is performed by pressing the film 12 at upper and lower positions. Since the cutter 34 is provided on one of the lateral sealers 32, the film is cut at the same time when the tubular film 12 is clamped by the sealers 32, 32.

A horizontal seal mechanism for reciprocally driving the horizontal sealers 32, 32 in a vertical bag-making filling and packaging machine is disclosed in, for example, JP-A-60-172606 and JP-A-5-176606.
The technique described in Japanese Patent Publication No. 2-156081 is proposed. Each of the lateral seal mechanisms according to these proposals uses a pneumatic actuator such as a fluid motor or an air cylinder as a drive source, and swings a crank linked to the actuator to move a pair of lateral sealers along a slide shaft. It is configured to move toward and away from each other oppositely.

[0005]

The pneumatic lateral sealing device according to the above-mentioned prior art has the advantages that the structure is relatively simple and the manufacturing cost can be reduced. However, the supply pressure and flow rate of the compressed air that drives the actuator are generally easy to change. If the initial set values for the supply pressure and the flow rate change, the operation timing of the horizontal seal mechanism changes, and there is a lot of fear that the packager will be bitten by the horizontal sealer. Further, it is pointed out that there is a problem in that the time during which the tubular film is pressed by the horizontal sealer changes, resulting in a defective seal such as insufficient sealing or melting of the seal portion. That is, in a horizontal seal mechanism that uses air pressure as a drive source, it is necessary to take stabilization measures so that the pressure and flow rate of the compressed air used for this do not fluctuate. It affected performance.

When the vertical bag-making filling and packaging machine is operated at a high speed or when a high degree of sealing property is required for the tubular film, the pressure applied when the horizontal sealer in the horizontal sealing mechanism clamps the film. Must be large enough. This is because the higher the speed of the packaging machine, the shorter the unit time in which the lateral sealer presses the film. Therefore, in the conventional lateral seal mechanism, it is necessary to change the pneumatic actuator such as a fluid motor or an air cylinder to a large capacity actuator to meet the demand for increased pressing force. Furthermore, by changing the material of the packaging film, or according to changes in various conditions such as the number of rotations of the packaging,
There is also a need to selectively change the type of the actuator. Moreover, the overall energy efficiency when using compressed air is at most about 64 to 72%, which is a relatively low rate.

[0007]

SUMMARY OF THE INVENTION The present invention has been proposed in view of the above-mentioned problems inherent in the vertical bag-making filling and packaging machine according to the prior art, and it is proposed to solve this problem at a high speed. Even if it is operated, there is no change in the operation timing of the horizontal seal device, and when the horizontal sealer is pinched, the applied pressure can always be set to an appropriate pressure according to various sealing conditions, and energy efficiency is further improved. It is another object of the present invention to provide an excellent lateral seal control method and its device.

[0008]

In order to overcome the above-mentioned problems and to achieve the intended purpose, a lateral seal control method according to the present invention is a method in which a film fed from an original roll is formed into a tubular shape by a bag making machine. The vertical edge of the tubular film is vertically sealed by a pair of horizontal sealers that horizontally oppose each other across the film feeding path while vertically stacking the overlapped edge portion of the tubular film. In a vertical bag-making filling and packaging machine configured to perform horizontal sealing, a servo motor is used as a drive source for the pair of horizontal sealers, and the servo motor is kept constant based on the timing at which the horizontal sealer presses the tubular film.
It is characterized in that the film sealing pressure by the lateral sealer is maintained at an appropriate pressure by controlling the rotational torque value to be maintained .

In order to overcome the above-mentioned problems and achieve the intended purpose, a lateral seal control device according to another invention of the present application forms a film fed from an original roll into a tubular shape by a bag making machine, A vertical seal is applied to the stacking edge of the tubular film, and a pair of horizontal sealers that horizontally oppose each other across the film feed path allows the vertical position of the package to be dropped and supplied to the tubular film to be changed horizontally. In a vertical bag-making filling and packaging machine configured to seal, a servomotor provided in a drive source for opening and closing the pair of horizontal sealers and a servomotor connected to the servomotor are connected to control rotation of the motor. A servo control unit to perform, an encoder provided on the servo motor to detect the amount of rotation and output to the servo driver, and various control data required for packaging operation, which are connected to the servo driver. A data processing arithmetic unit for performing input storage and arithmetic operation, an origin sensor for outputting an origin signal serving as a reference for the opening / closing operation of the horizontal sealer to the arithmetic unit through an interface, and a lateral sensor incorporated in the arithmetic unit. A torque limit signal generator that outputs a torque limit signal when the sealer is closed, and a servo limit controller that receives this torque limit signal.
And a torque limit adjusting means for holding the motor at a constant rotational torque value .

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, a horizontal seal control method and device for a vertical bag-making filling and packaging machine according to the present invention will be described below with reference to the accompanying drawings with reference to preferred embodiments. 3 to 5
As shown in FIG. 2, the horizontal seal mechanism 36 that horizontally moves the horizontal sealers 32, 32 arranged opposite to each other horizontally toward and away from each other
Also, a second link 40 is provided, and the first link 38 is driven by the servomotor SM. That is, the two guide rods 42, 42 are horizontally opposed to each other with the vertical feed path of the tubular film 12 interposed therebetween, and the horizontal sealer 32 is attached to each slider 44 slidably inserted on the rods 42, 42. , 32 are fixed respectively. The first timing belt 50 is wound between the small-diameter pulley 46 attached to the servo motor SM and the large-diameter pulley 48 shown in FIG. 4, and the small-diameter pulley 5 coaxially fixed to the large-diameter pulley 48.
A second timing belt 51 is wound between the second timing belt 51 and another large-diameter pulley 54.

The following first link 38 is connected to the large-diameter pulley 54 in a relational manner. That is, one end of the link rod 58 is pivotally attached to the arm 56 coaxially fixed to the large-diameter pulley 54, and the other end of the link rod 58 is pivotally attached to the open end of the arm 62 fixed to the rotating shaft 60. 1
The link 38 is constituted. And the servo motor S
If M is rotated forward and backward at the required timing, the first link 38 is operated to rotate the rotating shaft 60 forward and backward at the required center angle. A second link 40 is connected to the rotary shaft 60 and the horizontal sealers 32, 32. That is, the illustrated arm 63 is inserted and fixed to the rotary shaft 60 at a portion deviated from the center thereof, and one end of a short link rod 64 is pivotally attached to the short side end of the arm 62, and The other end of the link rod 64 is pivotally attached to the one slider 44. Further, one end of a long link rod 66 is pivotally attached to the longitudinal end of the arm 62, and the other end of the link rod 66 is pivotally attached to the other slider 44, so that the toggle mechanism 41 as a whole. Are configured. When the rotating shaft 60 rotates forward and backward at the required center angle by the operation of the first link 38, the second link 40 also operates and separates the horizontal sealers 32, 32 (fully open) as shown in FIGS. 4 and 5. And the movement to bring them close (fully closed) is reciprocated. The servomotor SM is adapted to control the number of revolutions in response to a command from a control circuit described later.

Next, with reference to FIG. 1, description will be given of a control device that preferably achieves the lateral seal control method according to the embodiment. This control device includes a data processing calculation unit CPU that performs calculation processing of input data. This arithmetic unit CPU
A data input means 68 including, for example, a ten-key pad, various condition setting keys, etc. is connected to the interface 69, which allows various control data necessary for the packaging operation.
(Variety name of the object to be packaged, cut pitch of the film, the heating temperature of the sheet Lumpur body, set values of various timers, etc.) are input set. The calculation unit CPU has a built-in servo control unit 71 that controls the servo motor SM, and the servo motor SM and the control unit 71 are connected via a servo driver 70. A rotary encoder E for detecting the rotational position of the servo motor SM is attached to the servo motor SM, and the output of the encoder E is supplied to the servo driver 70.

As shown in FIGS. 3-5, a lateral seal mechanism 36.
In the large-diameter pulley 54, a slit disk 53 is arranged coaxially with the large-diameter pulley 54, and an origin sensor S for detecting the origin with respect to the maximum open position of the horizontal sealers 32, 32 is arranged with the disk 53 sandwiched therebetween. It is fixed (in FIG. 3, the sensor S is provided at a position different from those in FIGS. 4 and 5 to show the mounting state of the sensor S). And the origin sensor S
The signal from the arithmetic unit C is sent via the interface 73.
Input to PU. In addition, the arithmetic unit CPU is a horizontal sealer 3
It incorporates a torque limit signal generator 75 that generates a torque limit signal at a required timing during the closing time of 2,32. Then, the torque limit signal output from the torque limit signal generating section 75 is input to the relay means 72 such as a solid state relay, and the relay means 72 is turned on so that the torque limit volume 74 has a predetermined electric power. Pressure is supplied. This control voltage to the servo driver 70 via the torque limiting volume 74 is supplied by, the
Servo driver 70 in response to the control voltage, has a current value supplied to the servo motor SM adapted to variably control. The arithmetic unit CPU incorporates a clock pulse generator 76, which transmits a clock pulse based on one packaging cycle in the packaging machine.

The lateral seal control method according to the embodiment is achieved as follows. As mentioned above, the servo motor SM
The normal rotation and the reverse rotation cause the first link 38 and the second link 40 to perform a link motion, and the lateral sealers 32, 32 are opened and closed. As described above, by adopting the amplification mechanism including the rotary motion including the first link 38 and the toggle mechanism 41 including the second link 40, there is a substantial advantage that the servo motor SM having a relatively small output can be used as a drive source. . As a method for controlling the rotation of the servo motor SM in this case, speed and position feedback control is adopted, and the lateral sealers 32, 3 are used.
The rotational torque of the servo motor SM is controlled by changing the supply current when the second motor is closed. Then, as will be described later with reference to the timing chart of FIG.
Immediately before the closing of 2, 32 and immediately after the opening thereof, the servo motor SM can be current-controlled to maintain an appropriate sealing pressure according to the sealing conditions.

First, during the operation of the packaging machine, various control data necessary for the packaging operation are input and stored in the arithmetic unit CPU via the data input means 68. The horizontal sealer 3 output from the origin sensor S during the setting operation of the packaging machine.
The origin positions of 2, 32 are stored in the computing unit CPU, and another drive system of the packaging machine is stored according to the stored origin position.
A reference signal for synchronization with respect to (for example, a film feeding mechanism) is transmitted. By supplying this origin position signal and the drive control signal of the horizontal seal mechanism 36 according to the reference clock pulse signal from the clock pulse generator 76 to the servo driver 70, the servo motor S
A required speed command is given to M. In addition, the servo motor S
The rotary encoder E attached to M feeds back the current rotational position of the motor SM to the arithmetic unit CPU via the servo driver 70 and the servo control unit 71, and thereby the drive of the lateral seal mechanism 36 is controlled appropriately. . Therefore, even if the number of revolutions of the packaging machine increases or decreases, the horizontal sealers 32, 32 are opened and closed at a speed according to the number of revolutions, and the lateral seal mechanism 36 is always driven and controlled at the optimum operation timing. It is what is done.

As described above, the driving of the servo motor SM is controlled by the clock pulse, but the driving is started at a predetermined timing when the film is fed and fed.
That As shown in FIG. 2, to be packaged 28 required sensor from falling (not shown) is actuated to start timer T ₁ and detects the film 12 when the set time of the timer T ₁ is passed
The feeding supply of is started. In the vicinity of the supply end of the film 12, the timing command sealer start is issued, the transverse sealer activation timer T ₂ starts to drive the servo motor SM from the operation delay, thereby transverse sealer 3
2,32 closures are made. Therefore, the drive start timing of the lateral sealers 32, 32 can be arbitrarily changed by changing the setting time limit of the timer T ₂ . The vertical sealer closing timer T ₃ is set for a time based on a sealer start timing command. When the timer T ₃ times out, the vertical sealers 26, 26 are stopped according to the stoppage of the feeding and feeding of the film. Closure is made. Then, by the time-up of the sealer start timing command longitudinal and transverse sealer open timer T _4, which is set as a reference, said series of longitudinal sealer 26 and a transverse sealer 32, 32 begins to open. Note that the timing setting for opening and closing the vertical and horizontal sealers may be performed by setting a timer based on the end point of the feeding of the film 12.

Further, the data necessary for controlling the opening / closing positions of the horizontal sealers 32, 32 are obtained as follows. That is, the drive time of the servo motor SM (the time from the start of closing to the complete closing) is set as a ratio value in one wrapping cycle, and is set by data obtained by converting one wrapping cycle into an angle of 360 ° with respect to the reference clock pulse signal. I do.
Further, from the start of driving of the servo motor SM, the horizontal sealer 32,
The ratio of the horizontal sealers 32, 32 to one packaging cycle is determined by setting the angle conversion value for the time from when the motor 32 is closed to when the motor SM is reversely driven to open. Horizontal sealer 32, 32
Is determined by the encoder E attached to the servo motor SM from the origin position signal from the origin position sensor S and the set ratio of the horizontal sealers 32, 32 in one packaging cycle. Position control is performed.

Next, the horizontal sealers 32, 32 are used to form the film 12
The control in which the pressing force when pinching is can be made constant according to the set value will be described. From the torque limit signal generator 75 in the arithmetic unit CPU, the servo motor SM is output at a required timing according to the closing timing of the horizontal sealers 32, 32.
A torque limit signal is output in order to keep the rotational torque of the constant. As shown in FIG. 2, this signal is set to be output immediately before the lateral sealers 32, 32 clamp the film 12 and immediately after the sealers 32, 32 are released from the clamping force. The torque limit signal is shown in FIG.
Is input to the relay means 72 as described above.
As a result, the relay means 72 is turned on, and the relay means 7 is turned on.
The motor drive voltage supplied to the torque limit volume 74 from 2 is limited to a predetermined adjustment value set in the volume 74, is supplied to the servo motor SM via a servo driver 70. In other words, performs a control of the driving torque of the servo motor SM by restriction of the input voltage to the servo driver 70, the timing at which the voltage limit is performed, immediately before the transverse sealer 32 and 32 as possible closed (motor This is done between the forward rotation) and immediately after the horizontal sealers 32, 32 shift from the closed state to the open side (motor reverse rotation). In this way, since the current value of the drive current supplied to the servomotor SM is kept constant, the rotation torque of the motor SM is also controlled to a constant value, and therefore the lateral sealer 32,
The sealing pressure of the film 32 on the film 12 is also constant.

As described above, the torque control method for controlling the current value supplied to the servo motor SM is adopted as a method for keeping the pressure applied to the lateral sealers 32, 32 constant. For example, it is appropriately selected from the following methods. By the adjustment volume provided on the operation panel of the packaging machine,
A method of controlling the electric current of the servo motor SM to arbitrarily set the sealing pressure. The seal pressing force is numerically set by the ten-key pad provided in the data input means 68, or is selectively set by the condition setting key or the like provided in advance in the data input means 68, and the servo is performed according to the set value. sealing area obtained from the set wrapping film width and seal width depending on the method prepackaged condition for controlling the current of the motor SM, closing time of sheet Lumpur body, further preset sealing temperature, and other data input A method of calculating the seal pressing force to be given by the calculated value according to the material of the used film and automatically setting the control current of the servo motor SM from the calculated result.

The seal pressurizing time (horizontal sealer 32, 32
The closing time) can be arbitrarily changed by controlling the movement of the servo motor SM according to the value set by the data input means 68, the adjusting volume or the like according to the rotation speed of the packaging machine. Further, when the above method is adopted, it is not necessary to provide the relay means 72 and the torque limiting volume 74 described with reference to FIG. 1, and data input is performed by the torque limiting signal from the torque limiting signal generating section 75. the predetermined voltage on setting values input by means 68,
Servo driver 70 via digital / analog converter
Should be supplied to.

As can be seen from FIG. 2, the horizontal sealer 3
In the band in which 2,32 are opened to closed or the closed to open state is shifted, acceleration / deceleration control of the servo motor SM is performed to start / stop the servo motor SM at the closing start time, the opening completion time, and the opening start time. Vibration at the time of stoppage can be prevented, and shock at the time of collision of the horizontal sealers 32, 32 at the time of closing the seal can be buffered. The acceleration / deceleration value can be arbitrarily changed by a set input value in the data input means 68 as needed . The present invention is
Even a packaging machine having a configuration different from that of the vertical bag-making filling and packaging machine described above with reference to FIG. 6 can be suitably implemented. Further, in the illustrated embodiment, the horizontal sealing device is horizontally moved at a fixed position, but the present invention is not limited to this. For example, when the packaging film 12 is fed downward, a driving means for vertically moving the lateral sealing device downward at a speed synchronized with the film feeding speed while the lateral sealers 32, 32 sandwich the film 12 therebetween. With
The so-called box motion driving method can also be suitably implemented.

[0022]

As described above, according to the lateral seal control method and apparatus for the vertical bag-making filling and packaging machine according to the present invention, by using the servo motor as the drive source of the lateral seal mechanism, The opening and closing speed can be controlled accurately according to the number of revolutions of the packaging, and the sealer can be opened and closed by controlling the speed of the servo motor to increase and decrease at the closing and opening points of the sealer. Vibration related to operation can be prevented. Further, when the film is clamped by the pair of lateral sealers, it is possible to set a desired sealing pressure according to the sealing condition, and it is possible to always perform optimum sealing. Furthermore, it has become possible to improve energy efficiency by approximately 20% or more as compared with the case of using a pneumatic actuator.

[Brief description of drawings]

FIG. 1 is an example of a control block diagram that preferably achieves a lateral seal control method according to an embodiment of the present invention.

FIG. 2 is a timing chart showing respective operation timings of feeding a film, opening and closing a horizontal sealer, generating a torque limit signal, and opening and closing a vertical sealer.

FIG. 3 is a perspective view showing a schematic configuration of a horizontal seal mechanism including a first link and a second link.

FIG. 4 is a side view of the horizontal seal mechanism shown in FIG. 3 in an open state.

FIG. 5 is a side view of the horizontal seal mechanism shown in FIG. 3 in a closed state.

FIG. 6 is a perspective view showing a schematic configuration of a typical vertical bag making and filling machine.

[Explanation of symbols]

 10 original roll 12 film 14 feeding roller 16 dancer roller 18 guide roller 18 20 bag making machine 22 hollow mandrel 24 feed belt 26 vertical sealer 28 packaged item 32 horizontal sealer 36 horizontal sealing mechanism 38 first link 40 second link 41 toggle Mechanism 68 Data input means 70 Servo driver 72 Relay means 74 Torque limit volume 75 Torque limit signal generator

Claims (6)

[Claims] 1. A film rolled out from an original roll is formed into a tubular shape by a bag-making device, a longitudinal seal is applied to a superposed edge portion of the tubular film, and the film is horizontally opposed across a film feeding path. In a vertical bag-making filling and packaging machine in which a pair of horizontal sealers horizontally seals the upper and lower positions of an object to be packaged supplied to the tubular film, a servomotor is used as a driving source of the pair of horizontal sealers. Then, the servo motor is kept at a constant rotational torque value based on the timing at which the lateral sealer presses the tubular film .
By so that control, transverse sealing method for controlling a vertical bag filling and packaging machine being characterized in that so as to hold the film sealing pressure by the lateral sealer to appropriate pressure. 2. A film rolled out from an original roll is formed into a tubular shape by a bag-making device, a longitudinal seal is applied to a superposed edge portion of the tubular film, and the film is horizontally opposed across a film feeding path. In a vertical bag-making filling and packaging machine configured to laterally seal the vertical position of a packaged object dropped and supplied to the tubular film by a pair of horizontal sealers, provided in a drive source for driving the pair of horizontal sealers to open and close. Servo motor and connected to this servo motor via a servo driver,
A servo control unit that controls the rotation of the motor, an encoder that is provided in the servo motor and that detects the amount of rotation of the servo motor and outputs the rotation amount to the servo driver, and various control data that is connected to the servo driver and is necessary for packaging operation. A data processing calculation unit for performing input storage and calculation of the horizontal sealer, an origin sensor for outputting an origin signal serving as a reference for the opening / closing operation of the horizontal sealer to the calculation unit via an interface, A torque limit signal generator that outputs a torque limit signal when the sealer is closed, and receives the torque limit signal to keep the servo motor constant.
The horizontal seal control device for the vertical bag-making filling and packaging machine, comprising: Wherein the torque limit adjustment means includes relay means for supplying a control <br/> voltage receives a timing signal which is input from the torque limit signal generator, provided on an operation panel of the packaging machine, desired electric predetermined control voltage to the servo driver
Transverse sealing control of the vertical bag filling and packaging machine according to claim 2, wherein composed of an adjustment volume to be set to the pressure value. 4. The servo motor is controlled by the torque limit adjusting means.
The limit value for maintaining the constant torque value is
3. The control according to the set value by the data input means and the torque limit signal from the torque limit signal generator.
Horizontal seal control device for the described vertical bag-making filling and packaging machine. 5. The servo motor has a constant rotation torque value.
Limits for holding comprises a seal area which is calculated from a preset width of the film and the seal width according to packaging conditions, sealer closing time, and seal temperature data input values for other use films 3. The horizontal seal control device for a vertical bag-making filling and packaging machine according to claim 2, wherein the value is automatically selected as a value corresponding to the seal pressing force calculated from. 6. A horizontal seal mechanism having a pair of horizontal sealers is fixed to a first link that is connected to a servomotor and is rotated forward and backward at a required central angle, and a rotary shaft that is connected to the first link. 3. A toggle mechanism comprising: a second link that horizontally moves the pair of horizontal sealers to face each other.
The horizontal seal control device for the vertical bag-making filling and packaging machine according to any one of 5 to 5.