JP3800417B2 - Speed control device for sealing mechanism - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention is a seal mechanism for operating a block motion of a pair of heating seal bars arranged with a tube film moving in the longitudinal direction in the same direction as the film, and a seal bar moving process speed in the same direction as the film. The present invention relates to a control device that makes the maximum constant.
[0002]
[Problems to be solved by the invention]
While the belt-like film is rolled into a tube and transferred into a tube, the package is carried into the tube film at equal intervals, and the tube film is crossed so as to isolate each package by a pair of seal bars. In a bag-fill-fill-seal machine that seals, it is necessary to prolong the heating time for a film with a low melting degree. Therefore, both seal bars holding the tube film are moved in the same direction as the film for a certain period of time, and the same film. You must retreat away from the orbit. In short, both seal bars are operated by block motion.
[0003]
Conventionally, in Japanese Patent Laid-Open No. 7-291234, the revolution movement of the crankshaft causes the seal bar support frame to reciprocate along the tube film transfer path, while the pair of seal bars approach and separate from each other in the frame. Thus, it is disclosed that both seal bars operate in block motion. However, the crankshaft can only use one-half of its revolution track as the advance region of the seal bar support frame, and the top dead center and bottom dead center of the revolution track each have an extreme speed with a stop point between them. Therefore, there is a problem that the movement of the seal bar can be fixed only about 120 degrees.
[0004]
[Solution]
According to the present invention, a tube film is closed between the front and back packages, and at the same time, a pair of seal bars that perform vacuum suction from the cut portion formed in the closed portion into the film are provided in half of the revolution trajectory of the crankshaft. For the purpose of moving the region at a constant speed, the swinging motion of the arm with the support shaft at one end as a fulcrum is transmitted to the seal bar support frame via the connecting rod, and the support frame in the tube film transfer track and reciprocation, the pair of sealing bars disposed on the supporting frame, close to across the said tube film, a synthetic movement of the separating movement, the both sealing bars are operated block motion, the two seal bars the tube film The air in the film is removed by suction from the cuts made on the film by the seal bars while the pressure is being clamped. An apparatus for heat-sealing an eye, wherein a slider that slides a guide formed along the arm and a crank plate that is rotated by a servo motor are engaged via a crankshaft, and the slider that supports the slider, A support frame is connected via the above-mentioned rod, and between the maximum swing range of the arm (point 53 to point 54) and a 180-degree region (point 55 to point 56) on the revolution axis of the crankshaft. region (.theta.1, .theta.2) while forming an inversion region of the support frame such that said speed of said supporting frame in the region of the rotational angle 180 degrees of crankshaft kept constant, the operation signal for the servo motor And a controller for sending.
[0005]
Since the arm that swings by the circular revolving motion of the crankshaft uses the support shaft at one end as a fulcrum and the open end swings in an arc, the arm moves closer to the center of revolution of the crankshaft. It is possible to advance the seal bar support frame in a region more than a half of the revolution circle of the crankshaft, that is, in a region where the revolution angle is 180 degrees or more, and to move the seal bar support frame backward at a high speed in the remaining 180 degrees or less. It is. In short, the shorter the distance from the center point of the revolution circle to the center of the one end support shaft of the arm, the shorter the retreat area of the seal bar support frame, so that the advance area of the support frame can be adjusted to increase accordingly. It is. Therefore, by storing at least calculation data that stabilizes the swing angular velocity of the arm in the region of the revolution angle of 180 degrees in the memory, the controller outputs a calculation signal every time the crankshaft reaches the region of the revolution angle of 180 degrees. Therefore, the rotation speed of the servo motor is controlled so that the swing angular speed of the arm is constant. As a result, it is possible to perform the sealing for a relatively long time in which the vacuum suction in the tube film by the both seal bars and the heat sealing of the cut are performed in a stepwise manner without lowering the efficiency.
[0006]
DETAILED DESCRIPTION OF THE INVENTION
FIG. 2 is an overall view of the bag-filling and packaging machine. A belt-like film 12 drawn out by a roll 11 that rotates integrally with a motor 10 is rolled into a tubular shape 14 by passing through a cylindrical foamer 13. On the other hand, the chain conveyor 16 rotated by the carry-in motor 15. Each package 17 is carried into the tube film 14 at equal intervals. The frame 19 that supports the opposing ends of the first transport conveyor 18 and the second transport conveyor 18 includes a pair of upper and lower seal bars 21 and 22 for welding the film.
[0007]
FIG. 3 is a front view of the seal bar support frame 19 described above. A pair of a motor 23 mounted on the same type frame 19 and an operation shaft 25 rotatably supported between a pair of slide blocks 24 on both lower sides of the frame. And a pair of upper and lower frames 29, 30 are movable up and down on guide rods 28 erected from both slide blocks 24. In addition to supporting, the seal bars 21 and 22 are fixed to the upper and lower frames 29 and 30, respectively, and the operating shaft 25 is rotated in the forward and reverse directions by the power of the motor 23, whereby the bell crank 27 and the link 32 at both ends are provided. The upper and lower seal bars 21 and 22 connected via 33 are moved closer to and away from each other, and the tube film 14 is heat-sealed at regular intervals.
[0008]
FIG. 1 is a plan view of the frame 19 supported by a pair of rails 35 and a crank mechanism 36 for reciprocating the frame 19 along the rails 35. As shown in FIG. 4, the details of the crank mechanism 36 are supported by a bearing 38 fixed to a machine base 37 through a frame 37a, and an arm 40 is slidably supported through a support shaft 39 at one end. The center shaft 42 of the circular crank plate 43 is supported by the second bearing 41 that is fixed to the base 37 via the frame 37 b . Further, a groove type slider 45 is engaged with a slide guide 44 formed along the longitudinal direction of the lower surface of the arm 40, and the groove type slider 45 and a crankshaft rotatably supported on the eccentric portion of the crank plate 43. A shaft 49 connected to the servo motor 47 via the belt 48 is supported by the third bearing 50 and a pinion 51 fixed to the upper end of the shaft 49 is formed on the periphery of the crank plate 43. The parallel teeth 52 are engaged with each other.
[0009]
Therefore, in FIG. 5, when the crank plate 43 is rotated by the rotational power of the pinion 51 connected to the servomotor 47, the crankshaft 46 revolves around the central axis 42 along the track 53 indicated by the arrow. The groove-type slider 45 (see FIG. 6) fixed to is displaced along the slide guide 44 of the arm 40. As a result, the arm 40 swings around the support shaft 39 at one end. In this case, the top dead center 53 and the bottom dead center 54 of the arm 40 swinging around the support shaft 39 in FIG. 1 are 180 degrees region connecting the center shaft 42, that is, the range of the points 55 to 56 is θ1, The connecting rod 57 is formed so as to extend by more than θ2, and the frame 19 is advanced along the rail 35 at the upper part between the areas of both dead points 53 and 54 and is retracted at a high speed.
[0010]
7, when the crank shaft 46 revolves at a radius 80.36 mm circular orbit 58, the oscillation angle of length 310 mm arms that the support shaft 39 as a fulcrum, 36 split that is 10 degree angle increments In the divided analysis diagram, an arm swing angle value 59 per 10 degrees of each division and a millimeter value 60 in which the angle value is indicated by a straight line are displayed. When the arm swing angle numerical value 59 divided into 18 points between the points 55 to 56 corresponding to the radius of 180 degrees in the figure is expanded, it corresponds to the range of the arm swing angles 1 to 9 in FIG. The lengths of these angle values correspond to the corresponding dimensions in millimeters in the right column. Therefore, when the average value of the nine values in the right column is calculated to be 11.77 mm, the servo motor 47 controls the speed so that the arm moves 11.77 mm at each swing angle 1-9 . Note that the combined value of 7.76 mm in the lower part of the table is the displacement value of the support frame 19 in each of the areas θ1 and θ2 in FIG. 1, and the pair of seal bars 21 and 22 in FIG. Are moved at a uniform speed and folded back and forth in the front and rear areas 71 and 72 to perform block motion operation. In this case , the folding in the areas 71 and 72 corresponds to θ1 and θ2 in FIG.
[0011]
The reference cycle transmitter 74 in FIG. 10 is the same as the pulse transmitter 74 attached to the carry-in motor 15 in FIG. 2, and the pulse transmitter 74 has the same pitch as the carry-in pitch of the package 17 to the tube film 14. A signal is transmitted to the controller to control the servo motor 47 in the same cycle. The data shown in FIG. 8 and the formula for calculating the average value thereof are input to the memory 76 in FIG. 10, and the position angle from the rotation feedback signal 78 from the servo motor 47 in FIG. In addition to the calculation, the output speed of the servo motor 47 is controlled based on the correspondence data stored in the memory 76.
[0012]
When the length of the package 17 to be carried into the tube film is shortened by the carry-in conveyor 16 in FIG. 2, the speed of the film motor 10 is reduced to adjust the interval between the packages 17 to be kept constant. However, in this case, in FIG. 4, the screw rod 81 is rotated by the micromotor 80, and the pin 82 supporting the end of the connecting rod 57 is displaced along the guide 83, so that the reciprocating momentum of the seal bar support frame 19 in FIG. adjust.
[0013]
FIG. 11 shows a seal mechanism installed on the seal bar support frame. The mechanism sandwiches the tube film 14 between upper and lower blocks 85 and 86, and applies a vacuum pressure to the first vacuum lines 86 and 87 to thereby form the tube. The air in the tube film 14 adsorbed so as to form a gap between the films 14 and opened by the cutting action of the cutting blade 88 is removed from the second vacuum line 87 as indicated by a dotted arrow, and then the up and down In this configuration, the bag mouth is heated and sealed by the relative approach of both the seal bars 21 and 22. In this way, the mechanism performs the heat sealing process for the tube film and the vacuum suction process in two stages, and the traveling time on the straight track is relatively long. Therefore, the arm 40 shown in FIG. This is to make the best use of the constant speed movement.
[Brief description of the drawings]
[Fig. 1] Plan view of crank mechanism and seal bar support frame [Fig. 2] Side view of bag making filling and packaging machine [Fig. 3] Front view of seal bar support frame [Fig. 4] Side view of crank mechanism [Fig. Plan view of the previous figure [Fig. 6] Cross-sectional view of the connecting part of the crankshaft and the arm [Fig. 7] Explanatory diagram of the swing angle value of the arm [Fig. 9] Illustration of block motion trajectory of seal bar [Fig. 10] Illustration of control device [Fig. 11] Cross section of seal bar [Explanation of symbols]
14 ... Tube film 17 ... Packed object 19 ... Seal bar support frames 21, 22 ...- Ru bar 40 ... Arm 45 ... Slider 46 ... Crank shaft 47 ... Servo motor 57 ... Cont 74 74 ... Reference cycle transmitter 75 ... Controller 76 ... Memory 78 ... Feedback signal 79 ... Calculating device 80 ... Micro motor 81 ... Screw rod 82 ... Pin 83 ... Slide guide 88 ... Cutting cutter

Claims (3)

The arm swinging motion with the supporting shaft at one end as a fulcrum is transmitted to the seal bar support frame via the connecting rod, the reciprocating motion of the support frame in the tube film transfer track , and a pair of seals arranged on the support frame bar, close to across the said tube film, a synthetic movement of the separating movement, the both sealing bars are operated block motion during said both seal bars are nipped said tube film, a film with the two seal bars Is a device that heats and seals the cut after removing the air in the film from the cut formed in the device, and includes a slider that slides a guide formed along the arm and a crank plate that is rotated by a servo motor. The slider is engaged through a shaft, and the supporting slider and the supporting frame are connected to the stove. Linked via a de, a maximum Yuradoiki (point 53- point 54) of the arm, the region between the 180 ° in the orbit of the crank shaft area (point 55-point 56) (.theta.1, while forming an inversion region of the support frame to .theta.2), wherein as the speed of the support frame in the region of the rotational angle 180 degrees of crankshaft kept constant, and a controller for sending an operation signal to said servo motor Device with. The controller matches the rotation cycle of the servo motor with the cycle signal from the reference cycle transmitter, and the controller calculates the position angle from the rotation feedback signal from the servo motor by the arithmetic unit and stores it in the memory. The apparatus according to claim 1, wherein the output speed of the servo motor is controlled based on the correspondence data. A pin is engaged with a screw rod arranged along the arm, while an end of a conrod connected to a seal bar support frame is engaged with the pin, and the screw rod is rotated by rotation of the screw rod by a micro motor. 2. The device according to claim 1, wherein the device is displaced along the axis.