JPS624014A - Method and device for drawing band in packaging machine - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] [Industrial application field]

The invention relates to a method and device for tightening bands in a packaging machine.

[Technical background]

In the band tightening process in a packing machine, the band is fed out of the main body by a band supply mechanism inside the main body of the packing machine, and the band is placed around the object to be packed by a band guide arch outside the main body or by hand. grasp,
The band tightening mechanism inside the main unit wraps the band around the item to be packed (primary tightening), and then tightens it (secondary tightening). A configuration is adopted in which the strength of the force can be adjusted depending on the type of items to be packed. For example, flexible items such as futons require a tightening width that is considerably larger than the external dimensions of the items to be packed, while hard items such as cardboard or wooden boxes require tightening to the extent that the band does not sag around the items to be packed. This can be said to be sufficient strength. And of these tensile strength! Ill is performed by means of adjusting or detecting the start or end of the set tightening process.

[Prior art and problems]

As a means of such a tightening process, firstly, as a means of tightening the band with an arm,
As shown in No. 233, a main lever which vibrates in a constant stroke by a cam which rotates in response to a signal surrounded by an object to be packed, has a band guide groove in the upper part, and automatically returns by springing, and an upper part of the main lever. A stopper member is provided which pivotally supports a band clamping pawl that is rotated in one direction by a spring and biased away from the band guide groove surface, and limits the amount of vibration of a lever that operates this band clamping pawl. There are devices that can be moved and adjusted to set the tightening start time, and tightening devices that use a pair of four-wheels. A rotary ring that rotates in synchronization with the shaft is provided on a shaft that tightens and drives the shaft, and one end of a swinging arm is loosely fitted onto the shaft, and an idler roller is rotatably supported on the other end of the swinging arm. With,
The idler roller is brought into sliding contact with the rotary ring in a movable manner, and when the band is wound around the object to be packed and tightened, the inertia of the idler caused when the rotary wheel stops when the band is pulled back and the tightening is completed causes the swinging arm to be moved. A limit switch is configured such that it can be oscillated to freely open and close, and the drive shaft is stopped by a brake using the limit switch, and then the motor is stopped.
As shown in the figure, a pair of rollers that rotate in opposite directions are arranged side by side at appropriate intervals, and a packing band is wound around the pair of rollers in an S-shape, and one of the pair of rollers is tightened. A pinch roller is provided on the band supply end side of the driving roller, and is capable of slidingly contacting the tightening driving roller.
On the other hand, another roller that presses and biases the band feeding side of the packing band in one direction of the pair of rollers is rotatably supported on the shaft of the roller, and a limit that can be freely operated by movement of the other roller is provided. A means characterized in that a switch is provided, and a timer is provided which is activated by a signal from the limit switch, and the rotation of the q-lar for performing the tightening drive is freely controllable according to the time set by the timer. 4, as in JP-A No. 199408 of 1982, a rotation detecting section is provided to detect the rotation speed of a magnet that rotates in synchronization with the drive shaft of the tightening roller, and when the tightening of the band is completed, the rotation speed of the roller is increased. A system has been proposed in which the electromagnetic clutch interposed between the drive source and the drive source is de-energized by detecting a decrease in the set value and/or a stop. These conventional tightening strength control means, which are arm type with a limit of the first constant stroke, have a narrow control range in the final tightening process, cannot make fine adjustments or obtain weak tightening force, and also In addition, the control means for the tightening method using the roller is based on the tension of the spring, so the control range is narrow, and furthermore, the control means in the tightening method using the roller is narrow, and furthermore, in addition to the fourth means, It cannot be tightened with an extremely weak force, and, like the second method, it requires a large number of parts (and has a rather complicated structure, making it difficult to make it compact). When targeting an object, the desired tightening strength cannot be obtained.In other words, each set value does not correspond to the actual tightening state because it assumes unstable spring tension and slippage due to friction of an electromagnetic clutch, etc. However, there is a problem in that so-called variations increase.

[Purpose] The purpose of the present invention is to solve the above-mentioned problems of the prior art, and to easily achieve a tightening strength of 111 m, which is compatible with downsizing of the entire packaging machine, based on the actual tensile force applied to the band in the tightening process. The object of the present invention is to provide a tightening method and device that have less variation in performance. [Structure] In order to achieve the above object, the present invention firstly has the following features:
By tightening the band, a member that swings due to the tensile force applied to the band is held in a predetermined position by an electromagnet, and the swinging of the member is sensed by the tensile force applied to the band to be tightened against the magnetic force of the electromagnet, and the member is tightened. Second, the method is characterized in that the feed unit equipped with the mechanism for tightening the band is provided with a member that can rotate freely by the tensile force applied to the band when tightening the band, together with the feed unit or alone. This device is provided with a switch means for detecting the swinging of the member, and the member is provided so as to be freely held in a predetermined position by an electromagnet, and the tensioning force applied to the band during primary tightening and/or secondary tightening is applied to the device. A swinging member is held in a predetermined position by an electromagnet, and the member is caused to swing against the magnetic force of the electromagnet.

【Example】

The details of the present invention will be explained below based on Example #1, which illustrates one example. The feed unit 70 consists of a feed roller 23 connected to a drive source, and a substrate 41 bearing a driven roller 24 that rotates in sliding contact with the feed roller 23. A feed motor 21 is, for example, a reversible geared motor with an operating voltage of 100 V, is integrally equipped with a speed reducer, and is fixed to the substrate 41. The output shaft of the reducer passes through the substrate 41 and is connected to the drive shaft 37 of the feed roller 23. That is, as shown in FIG. 1, the feed roller 23 is rotatably fitted into a circular cutout of a stepped portion 66 made of a straight portion and a curved portion cut into the substrate 41, and is provided so as to be in pressure contact with a driven roller 24, which will be described later. It is being Further, in the substrate 41, a circular notch step portion 67 is formed to avoid the outer peripheral lower surface of the driven roller 24 through a band passing groove 69 formed in a narrow groove shape slightly wider than the band thickness, continuing from the step portion 66.
has been deleted. The widths of the step portions 66 and 67 and the band passage groove 69 are formed to be slightly larger than the width of the band used. 2 to 4, reference numeral 31 denotes a support plate, which is attached to the base plate 41 so as to cover the stepped portion 1h6.67, the band passage groove 69, and the band shooter 35, which will be described later. The band is rotatably held between the rollers to prevent the band from coming off the rollers and each band path when the band is supplied and pulled back. As shown in FIG. 4, the driven roller 24 is made up of a shaft 25 and a bearing 29, and an eccentric shaft 26 integrally protruding from the tip of the shaft 25 passes through the band support plate 31. The crank 27 is rotatably supported by a bearing plate 61 fixed to the support plate 31, and one end of the crank 27 is pivotally attached to the shaft head exposed from the bearing plate 61, and the other end of the crank 27 is attached to the base plate 41. One end of the spring is fixed and connected to the other end of the second spring. The crank 27 is biased by the spring 28 toward the back of the page in the figure around the eccentric shaft 26, and since the eccentric shaft 26 also rotates in the same direction, the shaft 25 of the driven roller 24 moves toward the feed roller 23. The outer periphery of the driven roller 24 is always pressed against the outer periphery of the feed roller 23. As shown in the figure, the feed roller 23 has rack-shaped unevenness 36 formed in an annular manner around the entire circumference.
Band shooter 35 with a tip shape that fits loosely into 6
is provided on the straight part of the stepped part 66 cut into the substrate 41. The feed unit 70, which consists of the pair of rollers 23, 24, a drive mechanism, the substrate 41, and the support plate 31, moves integrally in the band supply direction by the tensile force applied to the band when tightening the band. It constitutes a member that is swingably supported so as to be able to move toward and away from 13. In other words, the band adhesive,
Below one machine frame 13 that supports mechanisms such as cutting, bearings 44, 44 are attached to the surface on the feed motor 21 side, and a shaft 43 is rotatably attached to the bearings 44, 44 at one end of the shaft 43. is applied to the substrate 41, and the other end is applied to the plate piece 42 that supports the end of the feed motor 21 opposite to the substrate 41. Further, the feed unit is attached to the above-mentioned pivot position in consideration of the center of gravity of the entire feed unit 70 so that a slight gap 4B is created between the upper side surface of the board 41 on the side of the machine frame 13 and the upper edge of the machine frame 13. Further, an electromagnet 80 using a dry single-plate electromagnetic brake is installed at a portion of the support plate 31 that is bent parallel to the machine frame 13. That is, the support plate 31 has a planar cross-shaped shape with the edge on the side of the machine frame 13 bent at a substantially right angle, and the electromagnet 80 has a field core 81 containing a built-in coil fixed to the bent surface of the support plate 31. A shaft 82 having a spherical tip is fitted into the collar, and the rear end of the axis 84 of the shaft 82 is connected to the holding member 8.
3 to the side surface of the machine frame 13. Further, an armature 85 is fitted into the shaft core 84, and the armature 85 is provided with a recessed portion in the center insertion hole corresponding to the spherical surface of the tip of the shaft 82.
Further, a spring 86 that urges the armature 85 toward the field core 81 is mounted around the shaft core 84 . 87 is a nut that locks one end of the spring 86 and rotates to reduce the drag of the spring 86. do. Therefore, the shaft 8
2 and the armature 85 provided on this shaft head are fixed in position, and the field core 81 swings together with the substrate 41 and the support plate 31. In addition, a limit switch 45 is fixed to the machine frame 13,
The tip of a touch pin 46 protruding from the limit switch 45 is attached to the upper side of the body of the feed motor 21 with a slight gap therebetween. Therefore, the substrate 41
That is, the vibration of the feed motor 21 pushes the touch pin 46 and the limit switch 45 generates a signal. In FIG. 1, a limit switch 64 is provided at the edge of the band guide 57 below the seal unit 60, and is activated by the pushed-in band tip. In addition, 22 is a guide roller attached to the band insertion opening 34 of the band passage groove 69, 65 is a band tip insertion part,
The guide 68, which is attached to the guide 68, is normally biased by a spring and its tip is locked on the machine frame 13, and a band is allowed to pass between the lower arcuate curved portion and the upper surface of the feed roller 23. A band passage 47 is formed on the feed roller 23 with a gap therebetween, and is rotatably mounted as shown by the two-dot chain line in FIG. 1 as required. The seal unit 50 includes press members, etc., which grip the band tip and supply end, press and cut the overlapping surface of the band by a camshaft rotationally driven by a camshaft motor (not shown), and 64 is a right press. , 58 is left press,
55 is a medium press, 56 is a slide table, and 57 is a band guide. Then, a band passage groove 69 is inserted from the band reel (not shown).
The band is inserted through the band insertion opening 34 of the driven roller 2.
The eccentric shaft 26 of No. 4 is moved upward in the plane of the paper by the crank 27.
When the feed motor 21 is rotated in the normal direction, the feed roller 23 rotates for the time set by the timer, and the band is pushed through by forming a slight gap between the feed roller 23 and the driven roller 24. shooter 35
A predetermined amount of the band is supplied to the outside of the main body via the band passage 47 between the upper surface and the lower surface of the guide 68. Then, via a band guide arch (not shown) or manually, the tip of the band arranged or wound in a loop around the object to be packed is connected to the lower surface of the slide table 56 of the seal unit 50 and the band guide via the band tip insertion part 65. inserted onto 57,
When the limit switch 64 near the slide table 56 is pressed, a voltage is applied to the camshaft motor (not shown), and the camshaft begins to rotate, and when the right press 54 reaches a state where the band tip is gripped between it and the slide table s6, this occurs. is stopped by a signal from a switch means that detects the rotation angle of the camshaft. A rated voltage of 9 gf 30 V has already been applied to the coil of the electromagnet 80 by the main switch, and the field core 81 has attracted the armature 85, and the board 41
A gap 48 is formed between the machine frame 13 and the machine frame 13. When the limit switch 64 is pressed, a set tightening voltage of 10V, for example, is simultaneously applied to the coil of the electromagnet 80. The stop of the camshaft motor serves as a signal to start the reverse drive of the feed motor 21, and the band is moved to the feed roller 2.
3 and the driven roller 24 to wrap around the packaged object (primary tightening) and tighten it (secondary tightening). When the band is tightened around the item to be packed, the tension applied to the band causes the feed roller 23 and the driven roller 24 to
With the band sandwiched between them, a force acts to pull the board 41 back toward the machine frame 13 while rotating, and the field core 81 of the electromagnet 80 attached to the support plate 31 fixed to the board 41 acts.
A force is exerted to pull it back in the same direction.Therefore, it tries to separate from the armature 85, which is locked to the spherical head of the shaft 82 attached to the machine frame 13, but the armature 85 is pulled back to the field core 81 by the tightening setting voltage. The field core 81 is attracted until the tightening torque corresponding to this set voltage is exceeded, and the band tightening process continues. When the tightening torque is exceeded, the field core 81 separates from the armature 85 against the magnetic force of the electromagnet, and the swingable member consisting of the entire board 41 vibrates in the direction of the machine frame 13. This vibration is caused by the feed motor 21
The outer box of the feed motor 21 pushes the touch pin 46 of the limit switch 45 installed nearby, the limit switch 45 generates a signal, the front camshaft motor rotates again, and the band supply end is moved by the left press 58. A limit switch installed on the camshaft detects when the grip is held and the tightened state is maintained, and this signal causes the feed motor 21 to
Stops reverse rotation. Then, by rotating the camshaft,
The middle press 55 rises and the IW of the band overlapping part is heated by the heater.
II. The band supply end side is cut, the band information process is completed, the camshaft motor is stopped, and the feed motor 21 rotates forward for a set time to supply a predetermined amount of the band to the outside of the main body, and the field core 81 of the electromagnet 80 is A rated voltage is applied to the inner coil, and the member consisting of the entire board 41 which is swung by the band tension force returns to its original position due to its own weight and attraction by the magnetic force between the armature 85 and the field core 81. At this time, the abutment surfaces of the armature 85 and the shaft 82 are both formed into spherical surfaces that can be freely abutted, and the entire surfaces of both are tightly attracted. Therefore, by adjusting the voltage applied to the coil of the electromagnet 80, the force that causes the field core 81 to be separated from the armature 85 against the magnetic force due to the applied voltage due to the tensile force of the band applied when the band is tightened, that is, the m It is possible to control the tightening strength obtained by controlling the actuation timing of the limit switch 45. In the trial production experiment according to the present invention, stepless control results were obtained in the range of applied voltage from 24 V to OV, 6 kg of spring 8, and 1 kg of 1 t'. (pulled on a scale). Although not shown in the drawings, by interposing a flat ring made of an extremely thin and uniform thickness on the field core 81 side surface of the armature 85, a gap is formed between both members when the armature is attracted, and the field By reducing the magnetic force of the core, it is possible to control the weaker so-called 1 ultra weak tightening, and it is possible to wrap cake boxes and the like without crushing them (0.6 kg as measured above). In addition, by attaching another electromagnet to the armature side, the parts of the second electromagnet with the same polarity face each other, and by forming a gap between the feed unit 70 and the machine frame 13 due to the repulsive force of both electromagnets, the feed unit 70 is held in a predetermined position. Alternatively, the feed unit 70 may be held in place, and the feed unit 70 may be swung against the magnetic force of the electromagnet by the tension of the band due to tightening. In this case, it is theoretically possible to use a method in which one of the electromagnets is a permanent magnet and its magnetic poles are opposed to each magnetic pole of the other electromagnet. Furthermore, as described in the above-mentioned Utility Model Publication No. 57-27682 (in a tightening device equipped with four rollers that swing due to the tensile force applied to the band when tightening the band, the shaft supporting the roller is held in a predetermined position by an electromagnet). [Effects] As expected, the present invention has an extremely versatile configuration that enables precise control of the tightening strength without variation based on the tension when tightening the band. This makes it possible to provide an extremely effective tightening means that can accommodate not only the feed unit but also the downsizing of the entire packing machine.In the above embodiment, tightening in the secondary tightening is explained. However, the present invention can be similarly applied to the control of band pulling back by the rollers in arm-type tightening, that is, the next tightening, by using a timer that sets a uniform length. In other words, with the primary tightening using a timer, the band of the same length is pulled back regardless of the size of the item to be packed, and tightening is performed at a constant stroke, resulting in insufficient tightening. According to the present invention, in the case of two lemons, it is possible to automatically control the amount of band pulling back, that is, the amount of primary tightening, and it is possible to perform sufficient tightening for objects of any size.

[Brief explanation of the drawing]

The figure shows an embodiment of the invention. Figure 1 is a front view with the electromagnet and support plate omitted, Figures 2 and 3 are partially sectional plan views and side views of the main parts, and Figure 4 is a cross-sectional view of the feed roller and driven roller. FIG. 13...Machine frame 23...Feed roller 24
...Followed roller 31...Support plate 34...Pan F
tl inlet 35... Band shooter 37... Drive shaft 41... Board 43... Axis 45...
・Limit switch 46...Touch pin 47...
・Band passage 48...Gap 69...Band passage groove 70...Feed unit 80...94
611 stone g 1...Fieldco 185...Armature

Claims (2)

[Claims] (1) Packing in which the tip of the band supplied outside the main body is grasped, the band is tightened to tighten it to the object to be packed, and then the supplied end of the tightened band is grasped and the overlapping part of the band is glued in the tightened state. In the machine, when the band is tightened, a member that swings due to the tensile force applied to the band is held in a predetermined position by an electromagnet, and the swing of the member is sensed by the tensile force applied to the tightened band against the magnetic force of the electromagnet. A band tightening method characterized in that the band tightening is completed by (2) In a packing machine that is equipped with a mechanism for supplying and tightening the packing band in the main body, a gripping mechanism for the tip and supply end of the band, and various mechanisms necessary for packing such as gluing the overlapping part of the band, the above-mentioned band tightening is performed. A feed unit equipped with a mechanism for performing this operation is provided with a member that is swingable together with the feed unit or alone by the tensile force applied to the band when the band is tightened. A band tightening device characterized by being provided with a switch means for sensing rocking.