Vertical bag making, filling and packaging equipment

Abstract

To solve the problems that high-speed passage between an ultrasonic horn and a receiving roll shortens welding time and reduces seal strength and that lower feeding of packaging material sheets is intermittent so that seal strength becomes uneven with increased speed due to the larger speed difference and seal failures may occur at the time of deceleration.SOLUTION: A lower feeding of packaging material sheets S is performed in an intermittent feeding operation cycle of stop-acceleration-uniform speed-deceleration-stop. On the other hand, with an ultrasonic horn 25 and a receiving roll 27 as reference positions, the packaging material sheets S descend while passing through the reference positions at a constant uniform speed, and moreover, the uniform speed is slower than the uniform speed at the time of lower feeding. The relative passing speed is an absolute quantity, and the direction of the speed can be downward or upward. The seal up-and-down operation cycle includes rise and uniform speed - rise and deceleration - descent and acceleration - descent and uniform speed - descent and deceleration - rise and acceleration - rise and uniform speed. A constant relative passing speed is achieved by superimposing the operation cycle of lower feeding. Moreover, this relative passing speed is slower than the lower feeding speed.SELECTED DRAWING: Figure 7

Description

[Technical field]

[0001] The present invention relates to a vertical form-fill-seal packaging apparatus that fills the bags with contents such as tea leaves and seals the openings during a process of forming bags while feeding a continuous sheet of packaging material downward. [Background technology]

[0002] Extraction bags such as tea bags are manufactured by a form-fill-seal packaging apparatus which fills the packaging sheet with tea leaves or other contents and seals the opening during the process of forming a bag from the packaging sheet. When the form-fill-seal packaging apparatus is of the vertical type, it is equipped with a former which deforms the packaging sheet which is continuously fed out into a cylindrical shape, a supply chute which guides the packaging sheet downward along its outer surface, a vertical sealing unit which applies vertical seals to both joined edges to form the bag into a cylindrical shape, and a horizontal sealing unit which clamps the tubular packaging sheet on both sides in the horizontal direction and applies horizontal seals. In addition, the vertical seal is an ultrasonic method in which ultrasonic vibrations are generated in an ultrasonic horn under pressure to create a weld, and the joined edges are sealed by passing between the ultrasonic horn generating ultrasonic vibrations and a receiving roll. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2011-79536 A Summary of the Invention [Problem to be solved by the invention]

[0004] Recently, there has been a demand for increased productivity, but if the speed at which the packaging sheet is fed downward is increased, the joined edges pass between the ultrasonic horn and the backing roll at high speed, shortening the welding time and generally reducing the seal strength. In addition, because horizontal sealing is performed with the packaging sheet stopped, the downward feed is intermittent and the speed changes constantly - accelerating, constant speed, decelerating, stopping, accelerating, etc. - and the speed at which both joined edges pass between the ultrasonic horn and the receiving roll also varies. If the downward feed speed is increased, this difference will become larger, which can have adverse effects such as uneven seal strength and, when decelerating, glue residue can form, causing poor sealing.

[0005] The present invention has been made in response to the above-mentioned problems of the conventional technology, and has as its object to provide a new and useful vertical form-fill-seal packaging apparatus which, while continuing the intermittent downward feed operation, causes the vertical sealing unit, consisting of an ultrasonic horn and a receiving roll, to perform a characteristic up and down reciprocating motion corresponding to the intermittent operation, thereby making it possible to keep the relative passing speed of the joined edges between the ultrasonic horn and the receiving roll constant and slower than the downward feed speed of the seal, even during intermittent operation. [Means for solving the problem]

[0006] The present invention has been made to solve the above problems, and the invention of claim 1 relates to a vertical bag form, fill and pack a bag with contents such as tea leaves during a process of forming bags from a continuous packaging sheet that is intermittently fed downward by vertical and horizontal sealing, the vertical sealing unit that applies vertical seals to both joined widthwise edges of the packaging sheet by passing between an ultrasonically vibrating ultrasonic horn and a backing roll has a vertical reciprocating mechanism that reciprocates up and down while maintaining the opposing relationship between the ultrasonic horn and the backing roll, In an intermittent feed operation cycle of stopping, accelerating, constant speed, decelerating, and stopping the lower feed, the up-and-down reciprocating mechanism lowers the ultrasonic horn and the receiving roll at a constant speed slower than the constant speed during the constant speed stage of the lower feed, and raises them at a constant speed during the stop stage of the lower feed, and reverses the direction of the up-and-down acceleration movement when the speed becomes zero during the deceleration and acceleration stages of the lower feed, thereby performing the following during the intermittent feed operation cycle of the lower feed: The relative passing speed of both edges in the width direction is kept constant and slower than the down feed speed. This is a vertical bag making, filling and packaging device characterized by the above.

[0008] Claim 2 The invention is as follows: 1In the vertical form-fill-seal packaging apparatus described above, the up-down reciprocating mechanism is configured with a cam mechanism having a cam follower provided on a oscillating part that oscillates over a required angular range, and a grooved cam that follows the cam follower, and the ultrasonic horn and receiving roll fixed to the grooved cam reciprocate up and down while maintaining an opposing relationship due to the vertical displacement of the grooved cam.

[0009] Claim 3 The invention is as follows: 2 In the vertical form-fill-seal packaging apparatus described in the above, the swinging portion of the cam mechanism is constituted by a rotating surface portion that is rotated by the drive of a servo motor. Effect of the Invention

[0010] In the vertical bag making, filling and packaging apparatus of the present invention, the intermittent downward feed operation is maintained while the vertical sealing unit consisting of an ultrasonic horn and a receiving roll is made to perform a characteristic up and down reciprocating operation corresponding to the intermittent operation, so that even during intermittent operation, the relative passing speed of the joined edges between the ultrasonic horn and the receiving roll can be kept constant and slower than the downward seal feed speed. Therefore, even if the speed of the downward feeding of the packaging sheet is increased, stable sealing can be achieved with a constant sealing strength. [Brief description of the drawings]

[0011] [Figure 1] 1 is a perspective view of a main part of a vertical bag making, filling and packaging apparatus. [Diagram 2] FIG. 2 is a perspective view of the device shown in FIG. 1 as seen from the rear side. [Diagram 3] 3 is a perspective view of a portion relating to the vertical seal unit in FIG. 2. [Figure 4] FIG. 4 is a perspective view of the vertical reciprocating mechanism of FIG. 3. [Diagram 5] FIG. 5 is a design drawing of a cam mechanism included in the up-down reciprocating mechanism of FIG. [Figure 6]2 is a conceptual diagram of a process for making a bag from a packaging sheet using the vertical bag-making, filling and packaging apparatus of FIG. 1. [Figure 7] 6 is a timing diagram of the downward feeding of the packaging material sheet and the vertical reciprocating movement of the vertical sealing unit in the bag making process. [Figure 8] FIG. 8 is an explanatory diagram of how to read the timing diagram of FIG. [Figure 9] 9 is a perspective view showing the positional relationship between an ultrasonic horn and a receiving roll of a vertical sealing unit in the vertical bag form fill pack packaging apparatus of FIG. 1, corresponding to a predetermined lowering position of the lower feed in the timing diagram of FIG. 8. [Figure 10] FIG. 10 is a perspective view showing the positional relationship between the ultrasonic horn and the receiving roll of the vertical sealing unit, following FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] A vertical bag making, filling and packaging apparatus 1 according to an embodiment of the present invention will be described with reference to the drawings. A hopper is provided on the top of the main body of the machine, into which the measured amount of tea leaves is fed. A cylindrical supply chute is connected to the bottom of the hopper, and this supply chute is inserted into the main body of the machine. The packaging sheet that is continuously fed out is deformed into a cylindrical shape along the former, and then is guided along the outer periphery of the supply chute and fed downward in a cylindrical state, during which both widthwise edges of the packaging sheet are joined together and vertically sealed to form a cylindrical body, and then horizontally sealed in the cross direction. Figures 1 and 6 show the inside of the device body. In Figure 6, the packaging material sheet S is cylindrically shaped and fitted along the outer periphery of the supply chute, and both widthwise edges T are joined together and project outward. The position and shape of the supply chute can be indirectly identified, so they are omitted from the illustration for ease of viewing.

[0013] A storage section 3 is disposed on the rear side of the supply chute, and this storage section 3 is fixed to the device body. The storage section 3 is in the shape of a square tube, and a front section 3a is connected to a side section 3b, and 3b is connected to a rear section 3c to form an integrated unit. A lower feed mechanism 5 is attached to this. In this downward feed mechanism 5, two pairs of rollers 7, 7 are arranged vertically with a gap between them. The pair of rollers 7 is composed of a drive feed roller 9 and a driven feed roller 11 arranged next to each other in the horizontal direction. The outer circumferential surfaces of the two feed rollers 9, 11 are closely opposed to each other and rotate in opposite directions so as to downward feed anything sandwiched between them. The feed track is set so that both joined widthwise ends T of the packaging material sheet S are sandwiched therebetween, and the entire sheet is downward fed while the cylindrical portion is rubbed against the supply chute. Between the upper roller pair 7 and the lower roller pair 7, the packaging sheet S is pulled with a predetermined tension and is kept taut.

[0014] As shown in FIG. 2, the support shafts of the drive feed roller 9 and the driven feed roller 11 are rotatably supported by bearings and penetrate the front part 3a into the storage part 3, and a drive gear 13 and a driven gear 15 are attached to the support shafts. The drive gear 13 and the driven gear 15 are fixed while maintaining a meshed state. A drive motor 17 and a reducer 18 are attached to the outer surface of the back part 3c, and the drive shaft of the reducer 18 penetrates the back part 3c into the storage part 3. The rotational drive force of this drive shaft is transmitted to the drive gear 13 through a transmission mechanism including a timing belt 19 and a pulley 21. The rotational drive force from the drive motor 17 is transmitted to the drive gears 13, 13 of the two roller pairs 7, 7 through one timing belt 19, and the lower feed of the two roller pairs 7, 7 is interlocked.

[0015] An ultrasonic horn 25 and a receiving roll 27 of a vertical seal unit 23 are disposed between the upper and lower pairs of rollers 7, 7. The ultrasonic horn 25 is in the shape of a coaxial cylinder, and the rim of the circular tip surface 25a of the ultrasonic horn 25 is composed of an end surface perpendicular to the axial direction. The ultrasonic horn 25 is disposed with the axial direction horizontal, and the tip surface 25a faces the backing roll 27 side. The receiving roll 27 is disk-shaped, and the outer peripheral surface 27a is a perfect circle that is coaxial with the axial direction. The receiving roll 27 is disposed in such a position that the axial direction faces the front-rear direction, and the axis of the receiving roll 27 is located on an extension of the axial direction of the ultrasonic horn 25. The tip surface 25a of the ultrasonic horn 25 faces closely to the outer peripheral surface 27a. In addition, the gap between the tip surface 25a of the ultrasonic horn 25 and the outer circumferential surface 27a of the receiving roll 27 is perpendicular to the feed trajectory of the packaging material sheet S that is sandwiched between the drive feed roller 9 and the driven feed roller 11 of each of the upper roller pair 7 and the lower roller pair 7 and fed downward.

[0016] 2 and 3, reference numeral 29 denotes an attachment portion, which is formed by connecting the edges of a rectangular plate surface portion. The edges of rectangular side portions 29b, 29b are connected at right angles to both left and right edges of the main portion 29a. The plate surfaces are connected while facing horizontally, and when viewed from above and below, both side portions 29b, 29b protrude forward from the main portion 29a. The ultrasonic horn 25 is attached to one of the side portions 29b, 29b, and the backing roll 27 is attached to the other. The side portions 29b, 29b protrude to the front side through openings 3d, 3d (only one of which is shown in Figure 3) formed in the front portion 3a of the support base 3, and the main portion 29a wraps around to the back side of the front portion 3a and enters the inside of the storage section 3. The main portion 29a is disposed between the upper driving gear 13 and the driven gear 15 of the lower feed mechanism 5 and between the lower driving gear 13 and the driven gear 15 of the lower feed mechanism 5, in the vertical direction.

[0017] A guide rail 31 is attached to the rear surface of the front portion 3a. The guide rail 31 is elongated with the up-down direction as the guide direction, and has guide grooves formed on both the left and right sides. On the other hand, a concave sliding block 33 is attached to the front surface of the main portion 29a, and this sliding block 33 is in sliding contact with the guide rail 31 and is guided as it moves up and down. Therefore, the ultrasonic horn 25 and the receiving roll 27 of the vertical sealing unit 23 are capable of moving up and down between the upper roller pair 7 and the lower roller pair 7 while maintaining an opposing relationship.

[0018] A grooved cam 35 is attached to the back surface of the main portion 29a, and this grooved cam 35 is positioned opposite the sliding block 33 with the main portion 29a in between. The grooved cam 35 is positioned laterally offset from the drive gear 13 etc., and does not interfere with the drive gear 13 etc. The groove 35a of the grooved cam 35 extends horizontally and opens toward the rear side. As shown in Fig. 4, a protruding cam follower 37 enters the groove 35a from the rear side and is slidably fitted in the groove 35a.

[0019] A shaft 37a of the cam follower 37 is attached to a rotating disk 39, and the cam follower 37 protrudes in the front direction. A rotating shaft 42a is attached to the back surface of this rotating disk 39. The servo motor 41 and the reducer 42, like the drive motor 17 and the reducer 18, are also attached to the outer surface of the back surface portion 3c, and the rotating shaft 42a of the reducer 42 penetrates the back surface portion 3c and enters the inside of the storage portion 3, thereby constituting the above-mentioned cam mechanism. The shaft 37a of the cam follower 37 is offset toward the outer periphery of the rotary disk 39, and when the rotary disk 39 is oscillated by the drive of the servo motor 41, the grooved cam 35 is pushed by the cam follower 37 and changes from the uppermost position to the lowermost position. Therefore, the vertical reciprocating mechanism having the above-mentioned configuration enables vertical reciprocating movement between the upper roller pair 7 and the lower roller pair 7.

[0020] As shown in FIG. 5, this vertical form fill pack packaging apparatus 1 is designed to swing within an angular range of 155.8° to produce 120 bags per minute, with a lowering and raising range of 44 mm at that swing angle. As shown in Fig. 6, in the process of the packaging sheet S being fed downward, it first passes through the vertical sealing unit 23, then passes through the static electricity removing device 43, and then passes through the horizontal sealing and cutting unit below. In the horizontal sealing and cutting unit, the cylindrically formed packaging sheet S is sealed in the horizontal direction, and the vertical middle part of the horizontal seal is cut to form bags filled with tea leaves and the like, which are then separated from the subsequent continuous packaging sheet S. In this horizontal sealing and cutting unit, a pair of pressing pieces press the cylindrical packaging sheet S in a flattened state, and horizontal sealing and cutting is performed with the vertical movement stopped.

[0021] Therefore, the downward feeding of the packaging sheet S is performed in an intermittent operation cycle of stop-acceleration-constant speed-deceleration-stop, and the transverse sealing and cutting is performed during the stoppage. On the other hand, vertical sealing is performed when the joined widthwise edges T of the packaging material sheet S pass between the ultrasonically vibrating ultrasonic horn 25 and the backing roll 27, and the ultrasonic horn 25 and the backing roll 27 move back and forth in the vertical direction. Figures 7 and 8 are timing diagrams of the downward feeding of the packaging material sheet S and the up and down reciprocating movement of the vertical sealing unit 23 in the bag making process when the vertical bag making, filling and packaging apparatus 1 produces 120 bags per minute, and the upper and lower sealing positions are indicated by the ultrasonic horn 25 and the receiving roll 27.

[0022] The downward feeding of the packaging sheet S is performed in an intermittent feeding operation cycle of stop-accelerate-constant speed-deceleration-stop, and the packaging sheet S is consistently displaced in the downward direction with stops along the way. In contrast to this, the ultrasonic horn 25 and the receiving roll 27 are set as reference positions, and the packaging material sheet S passes through this reference position at a constant uniform speed while descending, and this uniform speed is slower than the uniform speed during downward feeding. The constant speed at which the seal passes through this reference position corresponds to the relative passing speed. The relative passing speed is an absolute value, and the speed direction can be either downward or upward. For example, when the top and bottom of the seal are downward, the relative passing speed is the difference between the speed of the bottom feed (absolute value) and the speed of the top and bottom of the seal (absolute value), and when the top and bottom of the seal are upward, the relative passing speed is the sum of the speed of the bottom feed (absolute value) and the speed of the top and bottom of the seal (absolute value).

[0023] The operation cycle of the up and down sealing is as follows: constant upward speed - decelerate upward - accelerate downward - constant downward speed - decelerate downward - accelerate upward - constant upward speed. When this is superimposed on the operation cycle of the downward feeding of the packaging material sheet S, it becomes as shown in the bottom part of Figure 7, and a constant relative passing speed is achieved. During the constant speed stage of the downward feed, the upper and lower seals are lowered at a constant speed that is slower than the constant speed, and during the stopping stage of the downward feed, the upper and lower seals are raised at a constant speed, and during the deceleration and acceleration stages of the downward feed, the direction of the vertical acceleration motion of the upper and lower seals is reversed when the speed reaches zero. The ultrasonic horn 25 and the receiving roll 27 are stationary, and the packaging sheet S passes between them at a constant speed and descends in an artificial manner. Moreover, the passing speed is the relative passing speed described above, and the state in which the packaging sheet S is fed slower than the actual downward feeding speed is artificially reproduced.

[0024] Figures 9 and 10 are flip-book style illustrations showing the state of the vertical form-fill-seal packaging apparatus 1 when the ultrasonic horn 25 and receiving roll 27 (=upper and lower seals) are lowered 5 mm at a time from the origin position shown in Figure 6. Due to the positional relationship between the pair of rolls 7, 7, the transition caused by the descent of the ultrasonic horn 25 and the receiving roll 27 can be easily visually confirmed.

[0025] Even if the downward feed of the packaging material sheet S is intermittent, the relative passing speed of the joined edges T between the ultrasonic horn 25 and the backing roll 27 is constant, so the seal strength is always constant. When producing 120 bags per minute, the downward feed speed of the packaging material sheet S also increases, but since the ultrasonic horn 25 and the backing roll 27 descend to follow the downward feed, a slow passing speed can be achieved when producing about 60 bags per minute, based on the ultrasonic horn 25 and the backing roll 27, and the seal strength does not decrease.

[0026] Although the embodiment of the present invention has been described in detail above, the specific configuration is not limited to this embodiment, and the invention also includes design changes within the scope of the present invention without departing from the gist of the present invention. For example, the vertical reciprocating mechanism is equipped with a compact cam mechanism to achieve highly accurate displacement, but is not limited to this and may be anything that can perform vertical reciprocating motion to achieve the above-mentioned operation cycle. [Explanation of symbols]

[0027] 1... Vertical bag making, filling and packaging device 3... Storage section 3a... Front section 3b...Side part 3c...Back part 3d...Opening 5... Lower feed mechanism 7... Roller pair 9... Drive feed roller 11... driven feed roller 13... drive gear 15... driven gear 17... Drive motor 18... Reducer 19... Timing belt 21...pulley 23...vertical seal unit 25: ultrasonic horn 25a: tip surface 27: receiving roll 27a... outer circumferential surface 29... mounting portion 29a... main portion 29b... Side portion 31... Guide rail 33... Sliding block 35... Groove cam 35a... Groove 37... Cam follower 37a...shaft 39...rotating disk 41...servo motor 42...Reduction gear 42a...Rotary shaft 43...Static eliminator S...Packaging material sheet T...Both edges in the width direction

Claims

1. In a process of forming bags by vertical and horizontal sealing of a continuous sheet of packaging material that is intermittently fed downward, a vertical form-fill-seal packaging device fills the bag with contents such as tea leaves, A vertical seal unit that applies vertical seals to both joined widthwise edges of the packaging material sheet by passing between an ultrasonically vibrating ultrasonic horn and a backing roll includes a vertical reciprocating mechanism that reciprocates vertically while maintaining an opposing relationship between the ultrasonic horn and the backing roll, The intermittent feed operation cycle of the bottom feed is: stop, acceleration, constant speed, deceleration, stop. The vertical reciprocating mechanism moves the ultrasonic horn and the receiving roll in an operation cycle of ascending at a constant speed, ascending at a constant speed, descending at a constant speed, descending at a constant speed, descending at a constant speed, ascending at a constant speed, ascending at a constant speed, During the constant speed stage of the downward feed, the material is lowered at a constant speed slower than that. When the bottom feed stops, the material is raised at a constant speed. During the deceleration and acceleration phases of the bottom feed, the direction of the vertical acceleration motion is reversed when the speed becomes zero.

2. A vertical bag making, filling and packaging apparatus comprising: a lower feed speed and a lower opening speed, the lower feed speed being constant and slower than the lower feed speed during the lower feed intermittent feed operation cycle.

2. In the vertical bag making, filling and packaging apparatus according to claim 1, The up and down reciprocating mechanism is The device is configured with a cam mechanism having a cam follower provided on a swinging part that swings over a required angle range and a grooved cam that follows the cam follower, A vertical form-fill-fill-seal packaging device characterized in that, as the grooved cam is displaced in the vertical direction, an ultrasonic horn and a receiving roll fixed to the grooved cam reciprocate up and down while maintaining an opposing relationship.

3. In the vertical bag making, filling and packaging apparatus according to claim 2, A vertical bag making, filling and packaging device, characterized in that the swinging portion of the cam mechanism is composed of a rotating surface portion that is rotated by the drive of a servo motor.

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