JP7330569B2 - cutter unit - Google Patents

Description

According to the present invention, in the process of packaging instant noodles or foods, powder or liquid soup, kayaks such as dried vegetables, condiments, seasoning oils, freshness preserving agents, drying materials, etc., are placed in individual pouches on top of the instant noodles or foods. It relates to a cutter unit that cuts a continuous package into small bags.

Conventionally, a sachet loading device cuts a continuous package (also called 'continuous pouch' or 'continuous sachet') in which small sachets (also referred to as 'pouches') are continuous into individual sachets by means of a cutter unit. A sachet is put into an object to be put in such as. There are various types of cutter units such as a guillotine cutter unit and a rotary cutter unit.

[Conventional guillotine cutter unit]
A guillotine type cutter unit is disclosed in Patent Document 1 (see FIGS. 17 to 23 thereof) having the following structure and functions.

In a conventional guillotine type cutter unit, a slider-crank mechanism that stops the relative reciprocating motion of the upper blade and the lower blade every cycle is arranged symmetrically, and two cutter blades (upper blade/lower blade ), the blade edge is moved back and forth against each other while the back surface of the blade is in close contact.

When the cutting edges of the upper and lower blades are in an open state, the nip rolls holding the vertical seal of the continuous package feed the horizontal seal portion of the pouch to be cut and separated to the cutting position by the conveying amount obtained by pitch detection. After that, the transport stops.

When the conveying of the continuous package is stopped, the slider-crank mechanism is actuated, and the two cutter blades move forward from the open state to narrow the gap, cut the laterally sealed portion, and then open again and stop.

The back-and-forth motion of the cutter unit and the continuous pouch feeding motion must be horizontal (opening and closing of the cutter) and vertical (conveyance of the continuous package) at the same height. alternately intermittently so as not to interfere with each other.

[Conventional rotary cutter unit]
A rotary cutter unit is disclosed in Patent Document 2 (see FIGS. 2 and 3 thereof) having the following structure and functions.

In a conventional rotary cutter unit, a continuous package is inserted between a pair of left and right rotary cutters that rotate relative to each other on the conveying path of the continuous package, thereby cutting the cutters provided on the peripheral surfaces of the cutters. The blade and cutter receiving blade are configured to cut the continuous package of packages at the transverse seal.

Conveyance of the continuous package and rotation of the rotary cutter are continuously operated without stopping, and the peripheral speed of the cutter blade and the conveyance speed of the continuous package are substantially synchronized during cutting of the horizontal seal.

The cutter cutting edge and the cutter receiving edge must be in contact over the entire width without gaps, and the contact pressure must be uniform. A mechanism for adjusting to

Conventional cutter units have the following problems.

[a] The horizontal movement of the cutter blade and the vertical conveyance of the continuous package interfere with each other during the cutting of the horizontal seal. Acceleration occurs.

That is, when a guillotine cutter with a horizontally moving cutter blade is used to cut the transverse seals of pouches, the vertical transport of the continuous package interferes with the horizontal movement of the cutter unit. Therefore, after the nip rolls start conveying the continuous package, the horizontal movement of the cutter blade is temporarily stopped until the horizontal seal portion of the small bag is completely conveyed to the cutting position. It moves horizontally to cut the laterally sealed portion of the continuous package. After that, transportation of the continuous packages is started again.

Therefore, an intermittent operation is performed in which the vertical conveyance of the continuous packages and the horizontal movement of the cutter blade are alternately performed.
For example, when operating at a cutting capacity of 250 (pieces/min), if the transport of continuous packages and the horizontal movement of the cutter blade can be performed simultaneously, both can be operated for a driving time of 0.24 (sec), but intermittent operation is performed alternately. When driving, each driving time is 0.12 (sec) (where sec: seconds, min: minutes, mm/sec ² : acceleration, same below).

For this reason, the transport of the continuous packages and the horizontal motion of the cutter blade driven intermittently operate in half of the total drive time, and by speeding up each motion speed, a large Acceleration is generated, and an impact inertial force acts on the continuous package and the motion mechanism.

[b] There is a limit to speeding up the continuous packaging because the impact at the start and stop of intermittent transportation causes fluttering and overrunning of the continuous package.
For example, when operating at a cutting capacity of 250 (pieces/min), the cycle time is 0.24 (sec). The operation time of the back and forth motion of the cutter blade is 0.12 (sec).

When the operation time is 0.12 (sec) and the trapezoidal wave is intermittently driven, the acceleration time and deceleration time are 25% (0.03 (sec)) of the operation time.

In the case of the standard pouch pitch of 70 (mm) applied to the pouch loading device, considering the acceleration/deceleration time of 0.03 (sec), the maximum transfer speed is 778 (mm/sec) (46.7m/min). acceleration is 25926 (mm/sec ² ) (2.65 G) (G: gravitational acceleration: 9800 (mm/sec ² )).

In general, when an object is conveyed, if its acceleration exceeds 1G (9800 (mm/sec ² )), there is a high possibility that the impact during acceleration and deceleration will destabilize the operation.

By the way, the continuous package is folded back by the guide rolls in the upper part of the small bag inserting device and conveyed vertically downward from the top.

When the sachets wrapped around the guide roll separate from the surface of the guide roll due to the inertial force of acceleration 2.65G at the start of intermittent transport, the continuous package that should be transported vertically downward at the exit side of the guide roll moves in the thickness direction. After it swells once, it tries to return to the original vertically downward line, causing fluttering during transport.

In addition, the -2.65G acceleration at stop acts on the mass of the continuous package conveyed downward from the guide roll to the cutting position, and an impact inertial force of "2.65 x mass" is added to the downward tension. . If the torque due to the downward tensile force, which is the sum of the conveying tension and the inertial force, becomes larger than the braking torque of the guide rolls, even if the conveying of the continuous package is stopped, the rotation of the guide roll does not stop, and the continuous package becomes excessive. An overrun phenomenon occurs.

Conveyance flapping caused by a shock of 2.65 G at the time of start-up reduces the accuracy of pitch measurement and causes variations in the conveyed amount of continuous packages based on the results of pitch measurement. As a result, when the continuous package comes to a stop, the lateral seal position is displaced from the normal cutting position, leading to troubles such as not being able to cut at the correct position.

If there is an overrun of the continuous package due to the impact of 2.65 G when the package is stopped, and there is a variation in the amount of transport at the same time, the horizontal seal will pass the cut position and the contents will be cut off. cause serious trouble.

Furthermore, when the continuous package is transported at a high speed with a maximum transport speed exceeding 400 (mm/sec), when the continuous package containing the contents with hard protrusions such as dried vegetables passes over the guide roll, the contents Problems such as the protrusions being pressed against the packaging material causing pinholes and breaking the contents become apparent.

When speeding up the cutting/loading capacity for intermittent transport, the speed of transporting continuous packages increases and the impact caused by the acceleration when stopped increases. High speed cutting is not possible.

[c] Since the continuous package is cut while the transport is stopped, the timing of the falling pouches is delayed as the cutting speed increases.

Since the continuous package is cut after stopping the conveying, the small bag after cutting is free-falling from the downward speed "0". The top small pouch of the continuous package to be cut and separated is generally put in contact with the sliding surface of the chute having a chute angle of 45 to 60°. For this reason, the drop is slow due to the frictional force of the cut instantaneous chute surface.

For example, given the chute angle .theta., the surface friction coefficient .mu., and the slip distance S, the time t and the distance S at which the ball slides down at the initial velocity Vo are expressed by the following relational expressions.

S=Vo×t+g×(sin θ−μ×cos θ)×t ² /2
However, g is gravitational acceleration (9800 (mm/sec ² ))
Calculating the above formula with Vo = 0, θ = 45°, µ = 0 to 0.5, and S = 100 (mm), the slip down time of the pouch is as follows.
However, the value in parentheses is the slide-down time when the continuous package transport and cutter horizontal motion are synchronized and the cutting edge down time during cutting is 189.8 (mm/sec) (initial speed of drop after cutting). represent.

μ = 0 t = 0.170sec (0.139sec)
μ = 0.1 t = 0.179sec (0.151sec)
μ = 0.2 t = 0.190sec (0.159sec)
μ = 0.3 t = 0.203sec (0.168sec)
μ = 0.4 t = 0.219sec (0.178sec)
μ = 0.5 t = 0.240sec (0.192sec)

According to the above calculation, when μ=0.5, the slip-down time of the pouch is 0.24 sec, which is the same as the cycle time for cutting the pouch at 250 (pieces/min).

If μ = 0.5 and the length of the pouch is 100 (mm), when the first pouch to be cut next has been transported to the cutting position, the end (edge on the cutting side) of the pouch that was cut last time is exactly 100 (mm). ) just slipped.

In addition, when used for a long time, the surface of the chute becomes dirty and the coefficient of friction may exceed μ > 0.5, so the tip of the next cut sachet collides with the rear end of the previously cut sachet, causing clogging in the chute. Occur.

When clogging occurs due to such a collision, the horizontal seal of the leading small bag of the continuous package sent into the chute ends before reaching the cutting position, and the contents are cut off, resulting in a "trunk break". .

In addition, in the post-process equipment that receives the small bags dropped from the chute, a phenomenon occurs in which the receiving timing is not in time.

High-speed cutting exceeding 200 to 220 pieces/min is not possible because of the clogging in the chute as described above and the timing delay to the next process equipment.

[d] A rotary cutter suitable for high-speed cutting exceeding 250 (pieces/min) has a complicated mechanism and is expensive, and it is difficult to align the cutting edge with the receiving edge.

A device equipped with a rotary cutter is used for high-speed cutting and feeding exceeding 250 (pieces/min), but the rotary cutter has the following drawbacks.

In order to ensure that the cutting edge of the cutting edge and the outer periphery of the receiving edge are in uniform contact over the entire width, the parallelism of each axis and the geometric and dimensional tolerances of the axis spacing are important. required, and the cutter unit becomes expensive.

The cutting edge and the receiving edge are consumable parts and must be replaced. However, when replacing the cutting edge or the receiving edge, it is necessary to arrange the cutting edges of multiple cutting edges on the same circumference and make adjustments so that they are evenly in contact with the outer circumference of the anvil. and it takes a long time to work.

Insufficient adjustment of the cutting edge and the receiving edge (If the cutting edge of the cutting edge does not contact the receiving edge with uniform pressure over the entire area, the contact pressure will be insufficient or excessive), resulting in poor cutting and cutting edge. Defects and failures such as premature wear occur.

JP-A-2004-223679 JP 2013-82474 A

As described above, in the conventional guillotine-type cutter unit, if the cutter blade is moved horizontally at the cut point and the continuous package is conveyed in the vertical direction, the blade edge and the pouches will interfere with each other. Since the horizontal movement of the blade and the vertical conveyance of the continuous package are alternately carried out (conveyance is carried out when the cutting edge of the cutter is open), the continuous package is conveyed intermittently. , and the acceleration at the time of starting and stopping becomes very large.

For this reason, due to the start/stop of intermittent transport, transport fluttering and impact inertial force not only cause pinholes and cracks and chips in the product quality, but also lead to unstable pitch detection and cut position. There is also a risk of overrun occurring from the beginning of the cut, resulting in a cut error or cut-off. For this reason, the guillotine type cutting has problems such as being unable to convey at a high speed exceeding 250 pieces/min.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a cutter unit capable of high-speed cutting even when using a guillotine-type cutting mechanism having a simple structure and easy blade engagement adjustment.

The present invention provides a cutter unit for cutting a continuous package in which small sachets are continuous, in which an upper blade unit having an upper blade and a lower blade unit having a lower blade are connected so that the upper blade unit and the lower blade unit can move back and forth. A drive consisting of an intermediate member which is a sliding pair and supports the blade edges of the upper blade and the lower blade so that the interval between them can be changed, and an upper blade crank unit and a lower blade crank unit for moving the upper blade unit and the lower blade unit. and a cutter unit.

In the present invention, it is preferable that the engagement of the cutting edges of the upper blade and the lower blade is such that the cutting edge of the upper blade, which swings and rotates by a spring, is pressed against the blade back surface of the fixedly mounted lower blade with a predetermined pressure. is.

In the present invention, the upper blade crank unit and the lower blade crank unit in the drive unit each have a drive shaft to which rotational force is input from a drive source, and a crank arm that rotates around the drive shaft. In the blade crank unit, the end of the crank arm spaced from the center of the drive shaft is rotatably connected to the upper blade unit, and in the lower blade crank unit, the end of the crank arm is spaced from the center of the drive shaft. The ends of the crank arms are rotatably connected to the lower blade unit, and it is preferable that the crank arms are continuously rotated at the same speed and in opposite directions.

In the present invention, assuming that the meshing margin between the upper blade and the lower blade is α, the upper blade and the lower blade are arranged when the left and right crank arms having a rotation radius R are horizontally arranged outward. is preferably D=4×R−α.

In the present invention, the drive section rotates the crank arms of the upper blade unit and the lower blade unit to rotate the blade edge of the upper blade in the section where the blade edge of the upper blade and the blade edge of the lower blade overlap. and the cutting edge of the lower blade is preferably rotated from top to bottom.

In the present invention, a conveying unit that conveys a continuous package in which a plurality of sachets are continuous at the lateral sealing portion, and a conveying control that controls the conveying speed of the continuous package in two stages: a first conveying speed and a second conveying speed. The horizontal seal portion is cut by the meshing of the upper blade and the lower blade and divided into the small bags, and the conveying control unit sets the conveying speed of the overlapping section to the second conveying speed and the first conveying speed is the amount obtained by subtracting the conveying amount at the second conveying speed from the pitch length of the small bag so that conveying for one pitch is completed before the crank arm makes one rotation. It is preferable to control the speed so that it can only be conveyed.

In the present invention, a rotation speed control unit for controlling the rotation speed of the crank arm is provided, and the rotation speed control unit keeps the upper blade and the lower blade constant in synchronization with the second conveying speed in the overlapping section. It is preferable to vary the speed of rotation of the crank arm so as to descend at speed.

In the present invention, when shifting between the second conveying speed in the overlapping section and the first conveying speed outside the section, the change in acceleration/deceleration does not exceed 1 G (9800 mm/sec ² ). Setting the speed is preferred.

In the present invention, when the second conveying speed of the continuous package is made to coincide with the lowering speed of the cutting edge when the cutting edge of the upper blade and the cutting edge of the lower blade start meshing, the cutting edge of the upper blade and the cutting edge of the lower blade The continuous package is fed so that the cut position of the horizontal seal of the continuous package is aligned with the meshing start position, and the cutting edge descends while advancing the meshing, and at the same time, the cutting position of the horizontal seal of the continuous package descends at almost the same position as the cutting edge position. It is preferable to do so.

In the present invention, the second conveying speed in the overlapping section and the first conveying speed other than this section are shifted from the vicinity of the rotation angle θ=90° of the crank arm to the start of meshing. It is preferable to set the shift section from the first conveying speed to the second conveying speed and the shift section from the second conveying speed to the first conveying speed from the completion of meshing to the vicinity of the rotation angle θ=270° of the crank arm.

According to the cutter unit of the present invention, (1) by simultaneously moving an object to be cut such as a continuous package in the vertical direction and moving the cutter unit horizontally, the drive time for each is the same as the cycle time. Continuous operation where the change in acceleration does not exceed 1G (9800mm/sec ² ).
(2) By changing the transportation of continuous packages from intermittent operation to continuous operation, fluttering and overrun due to start/stop are eliminated, and damage to continuous packages due to transportation (pinholes and breakage of contents) is eliminated. Stabilize pitch detection and eliminate cut mistakes.
(3) By cutting the sachets while conveying the continuous package downward at a speed, the time delay when the sachets slide down the chute at an initial speed of "0" is reduced, and the next cut sachets in the chute are cut. To eliminate clogging in a chute due to interference of small bags cut last time and cut-off accompanying the clogging, and to eliminate deviation of timing to the next process device.
(4) The guillotine-type cutter has an excellent effect that the blades can be easily matched by attaching the upper blade so that the blade rear surface of the upper blade is in close contact with the blade rear surface of the lower blade as a reference.

FIG. 4 is an explanatory plan view of the cutter unit according to the embodiment of the present invention; It is explanatory drawing by sectional drawing (sectional drawing toward the front plate side from a cutting line) which follows the AA' line of the top view of FIG. FIG. 4 is an explanatory diagram of the arrangement of the cutter unit; FIG. 4 is a motion analysis diagram of cutting edges of an upper blade and a lower blade; FIG. 4 is an explanatory diagram of positions and velocities of cutting edges of an upper blade and a lower blade; FIG. 10 is a diagram illustrating synchronization between the cutting edge descending speed and the pouch speed; FIG. 11 is an explanatory diagram of operation at a cutting edge lowering speed at the start of meshing; It is explanatory drawing of other driving|running. FIG. 4 is an explanatory diagram of a cutting edge and a pouch cutting position; It is explanatory drawing in the case of the slip-down time by the presence or absence of initial velocity.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

[1. Cutter Unit According to Embodiment]
1 and 2 show a cutter unit according to an embodiment. FIG. 1 is a plan view of the cutter unit viewed from above, and the continuous package 40 is indicated by a chain double-dashed line. FIG. 2 is a cross-sectional view (cross-sectional view from the cutting line toward the front plate side) along line AA' in the plan view of FIG.

As shown in FIGS. 1 and 2, the cutter unit 1 is suitable for use in a small bag inserting device (not shown) that cuts the continuous wrapper 40 into small bags and throws the small bags into objects. The continuous package 40 is transported with the vertically sealed portion sandwiched between the facing feed rollers 36 , 36 . A control motor (not shown) is connected to the feed rollers 36, 36 to constitute a conveying section. The control motor has a conveying control section (not shown), which controls the conveying speed of the continuous packages by varying the rotation speed of the feed roller.

[Objectives of the cutter unit]
The cutter unit 1 according to the embodiment aims to achieve the following objects.

[1] By moving the continuous package 40 in the vertical direction and moving the cutter blade in the horizontal direction at the same time, each driving time is the same as the cycle time, and the acceleration change during the motion is 1 G (9800 (mm/sec) ² )) shall be continuously operated.

[2] By changing the transportation of the continuous package 40 from intermittent operation to continuous operation, fluttering and overrun due to start/stop are eliminated, and damage to the continuous package due to transportation (pinholes and cracking and chipping of the contents). to stabilize pitch detection and eliminate cut mistakes.

[3] By cutting the sachets while conveying the continuous package 40 downward at a speed, the time delay when the sachets slide down the chute at an initial speed of "0" is reduced, and the next cut sachet and the previous cut sachet are cut. To eliminate clogging in a chute due to interference of a chute and breakage associated therewith, and to eliminate timing deviation to a next process device.

[4] Conventional rotary cutters for high-speed cutting have a structure that makes it difficult to align the blades, but by using a guillotine type cutter, it is possible to attach the upper blade so that the blade back is in close contact with the blade back of the lower blade as a reference. So you can easily match the blades.

[1.1 Overview of configuration of cutter unit]
As shown in FIGS. 1 and 2, the cutter unit 1 is mainly composed of an upper blade unit 2, a lower blade unit 3, and an upper blade crank unit 27 and a lower blade crank unit 33. As shown in FIG.

The upper blade unit 2 includes an upper blade shaft holder 4 , a connector 5 , a swivel shaft 8 , an upper blade holder 9 , an upper blade 10 , a connector base plate 12 , an upper blade guide mounting plate 13 and a guide ring 14 .

The lower blade unit 3 includes a lower blade shaft holder 15 , a lower blade holder 16 , a lower blade 18 and a lower blade guide bar 20 .

As shown in FIG. 1, the upper blade unit 2 of the cutter unit 1 includes a connector 5 held by an upper blade shaft holder 4, a swivel shaft 8 swingably incorporated in the connector 5, and the swivel shaft 8 having By holding the upper blade holder 9 and fixing the upper blade 10 to the upper blade holder 9, the upper blade 10 can be vertically swung around the pivot shaft 8 as a rotation axis. The lower blade unit 3 has a lower blade holder 16 fixed to a lower blade shaft holder 15, and a lower blade 18 is directly attached to the lower blade holder so that the lower blade unit 3 cannot swing and rotate.

The cutting edge 11 of the upper blade 10, which is pivotally rotatable about the turning shaft 8, is pressed against the blade rear surface of the lower blade 18, which is mounted so as not to be pivotally rotatable. The directional swing angle is restricted by the blade back surface of the lower blade.

Upper blade guide mounting plates 13 are attached to both sides of the upper blade unit 2 (both sides in the width direction of the continuous package 40 or both sides of the cutting edge 11 of the upper blade 10), and a guide ring 14 and a lower blade are assembled therein. By combining the guide bars 20 to form the sliding guide unit 21, the upper blade unit 2 and the lower blade unit 3 are coupled by the sliding guide unit (intermediate member) 21 that serves as a sliding pair.

A crankshaft (upper blade crankshaft) 22 is rotatably inserted into the upper blade shaft holder 4 , and a crank arm 23 is fixed to the crankshaft 22 . A drive shaft (upper blade drive shaft) 24 for rotating the crank arm 23 is incorporated on the side of the crank arm 23 opposite to the position where the crank shaft 22 is fixed, and an upper blade crank unit 27 is configured.
A crankshaft (lower blade crankshaft) 28 is rotatably inserted into the lower blade shaft holder 15 , and a crank arm 29 is fixed to the crankshaft 28 . A lower blade crank unit 33 is constructed by incorporating a drive shaft (lower blade drive shaft) 30 for rotating the crank arm 29 on the opposite side of the crank arm 29 from where the crank shaft 28 is fixed.
The fixed intervals between the crank shafts 22, 28 of the crank arms 23, 29 and the drive shafts 24, 30 are equal to the crank radius. The mounting positions of the crank arms 23 and 29 are symmetrical with respect to the intermediate position between the upper blade unit 2 and the lower blade unit 3 (conveyance line of the continuous package 40) and the respective drive shafts 24 and 30. Configured.

The upper blade unit 2, the lower blade unit 3, and the crank units 27, 33 are connected to each other by the crank shafts 22, 28 rotatably inserted into the upper blade shaft holder 4 and the lower blade shaft holder 15, forming a rotational pair.
The crank units 27 and 33 rotate the crank arms 23 and 29, thereby functioning as a driving section for moving the upper blade unit 2 and the lower blade unit.

[1.2 Configuration of each part]
[Upper blade unit 2]
In the upper blade unit 2, a U-shaped connector 5 in plan view is connected to the mounting surface of the upper blade shaft holder 4 (the surface facing the lower blade unit 3 side). A turning shaft 8 is rotatably inserted into the U-shaped corner portion of the connector 5 , and an upper blade holder 9 is fixed to the turning shaft 8 . An upper blade 10 is fixed to the upper blade holder 9, and the structure is such that the upper blade 10 can swing up and down with the swivel shaft 8 as a rotation axis.

An upper blade rotation pin 6 is inserted into a hole drilled from the mounting surface of the upper blade shaft holder 4 through a hole in the connector 5, and the upper blade shaft holder 4 is fixed to the connector 5 with a fixing bolt 6a.

A plurality of blind holes 5a, 5a, . A compression coil spring 7 is fitted in these blind holes 5a, 5a, .

The compression coil spring 7 contacts the end face of the upper blade holder 9 above the center position of the pivot 8, and the moment due to the repulsive force rotates the cutting edge 11 of the upper blade 10 clockwise in FIG.

By providing a gap between the upper blade holder 9 fixed to the turning shaft 8 and the connector 5, the cutting edge 11 of the upper blade 10 is restricted from rotating more than necessary in the vertical direction.

A connector base plate 12 is fixed to the lower surface of the connector 5, and upper blade guide mounting plates 13 are fixed to both end surfaces thereof. The clearance between the outer diameters of the guide wheels 14, 14 arranged in the same manner as the lower blade guide bar 20 matches the thickness thereof. Two pairs of opposing guide wheels 14 are arranged on the upper blade guide member 13 . If three or more pairs of guide wheels 14, 14 are used, it is difficult to adjust them in a straight line, and component tolerances and assembly variations are likely to occur. Therefore, it is preferable to increase the linear spacing as long as the stroke permits, because the bearings can be made larger and the load capacity can be improved. Of course, if the mounting accuracy of the guide wheels 14 permits, it is more preferable that the number of the guide wheels is 3 or more so that the guide can be guided without rattling.

[Lower blade unit 3]
As shown in FIG. 1, the lower blade holder 16 is directly connected to the lower blade shaft holder 15 (the lower blade holder 16 is abutted and fixed to the lower blade shaft holder 15), and has a U-shape with corners at both ends. is directly attached to the lower blade holder 16 .

Unlike the upper blade 10, the lower blade 18 is attached to the lower blade shaft holder 15 by a fixing method that does not swing or rotate.

The lower blade 18, which is U-shaped in plan view, has a blade edge 19 inside a pair of angular portions (horn portions 18a, 18a) extending from both ends of the width toward the upper blade unit. A shear angle oblique to the front-rear direction is provided.

The cutting edge 19 having a shear angle gradually recedes from the side of the front plate 34 that starts cutting the horizontal seal of the continuous package 40, and the distance from the cutting edge 11 of the upper blade widens.

A lower blade guide bar 20 is fixed to both outer end surfaces of the horn portions 18a, 18a, and its flat upper and lower surfaces are parallel to the blade back surface of the lower blade 18. As shown in FIG.

[Shape of upper blade 10 and lower blade 18]
In the embodiment, the upper blade 10 and the lower blade 18 may be flat blades with a flat blade back surface (a sliding surface where the upper blade 10 and the lower blade 18 are in close contact), or a multi-stripe blade as partially shown in FIG. A wavy blade machined so that the V-groove of the upper blade 10 and the lower blade 18 are aligned in the sliding direction can be used. The upper blade 10 and the lower blade 18 have cutting edge shapes in which a large number of V-shapes are connected, similar to the cutting edge shape of so-called pinking scissors. This V-grooving makes it possible to cut the laterally sealed portion of the continuous package without letting it escape, and at the same time, form a wavy cut that facilitates tearing when opening the small pouch. The V-grooves are formed on the blade back surfaces of the upper blade 10 and the lower blade 18 up to both end portions of the blade width.

In the embodiment, the V-groove uses a V-grooving blade (wavy blade) that forms a wave-shaped cut. A blade (flat blade) (without V-grooving) can be used.

As shown in FIG. 1, the lower blade 18 has a U-shape in plan view, and horn portions 18a, 18a at both ends of the U-shape engage the cutting edges 11 and 19 of the upper blade 10 and the lower blade 18. In order to match the blade line position of the V-groove, the horn portions 18a, 18a (blade back surface) are also V-grooved and aligned with the V-groove of the upper blade 10.

[Sliding guide unit 21]
As an intermediate member in the embodiment, the sliding guide unit 21 connects the upper blade unit 2 and the lower blade unit 3 with a sliding joint, and supports the blade edges of the upper blade and the lower blade so that the interval between them can be changed. A connector base plate 12, an upper blade guide mounting plate 13, a guide wheel 14, and a lower blade guide bar 20 are provided as a basic structure.

The upper blade edge 11 of the upper blade unit 2 and the lower blade edge 19 of the lower blade unit 3 are opposed to each other, and the upper and lower surfaces of the lower blade guide bar 20 are inserted between the guide rings 14 attached to the upper blade guide mounting plate 13. Thus, when the upper blade 10 and the lower blade 18 are moved back and forth, the guide wheel 14 rolls on the upper and lower surfaces of the lower blade guide bar 20 .

However, since the sliding guide by the guide ring 14 and the lower blade guide bar 20 alone is not regulated in the width direction, the upper blade shaft holder 4 and the upper blade crankshaft 22, the lower blade shaft holder 15 and the lower blade crankshaft 28 position by mounting the

An upper blade crankshaft 22 and a lower blade crankshaft 28, which are rotatably incorporated in the upper blade shaft holder 4 for driving the upper blade 10 and the lower blade shaft holder 15 for driving the lower blade 18, are stepped shafts. The contact surfaces (with which the upper blade shaft holder 4 and the lower blade shaft holder 15 abut) of the stepped portions 22a and 28a are equidistant from the surface of the front plate 34 on which the cutter unit 1 is mounted. By positioning and fixing the upper blade shaft holder 4 and the lower blade shaft holder 15 on the basis of this contact surface, the center positions of the upper blade 10 and the lower blade 18 in the width direction (positions of the rotation pins 6 and 17) are aligned.

In addition, the guide wheels 14, 14 are arranged (set) so as to vertically face each other on the upper and lower surfaces of the lower blade guide bar 20, and the vertically set guide wheels 14, 14 are arranged in the longitudinal direction of the lower blade guide bar 20. By arranging a plurality of guide rings 14, 14 at intervals, and arranging the outer circumferences of the guide wheels 14, 14 in close contact with the upper and lower surfaces of the lower blade guide bar 20, it is possible to eliminate rattling in the vertical direction, and the upper blade The unit 2 and the lower blade unit 3 are combined horizontally.

Therefore, the connector 5 attached to the connector base plate 12 and the blade edge 11 of the upper blade 10 and the blade back surface of the lower blade 18, which are attached via the swivel shaft 8, are configured to move back and forth while maintaining a horizontal state. It's becoming

With the above configuration, the upper blade 10 and the lower blade 18 are configured such that the upper blade crankshaft 22 and the stepped portions 22a and 28a of the lower blade crankshaft 28 for fixing the upper blade shaft holder 4 and the lower blade shaft holder 15 in the width direction of the blade. The cutting edges 11 and 19 of the upper blade 10 and the lower blade 18 are slidably guided by the upper blade guide mounting plate 13, the guide wheel 14 incorporated therein, and the lower blade guide bar 20. As a result, when the upper blade 10 is moved in opposition to the lower blade 18, the blade edge 11 of the upper blade and the blade edge 19 of the lower blade move back and forth in close contact with each other without being displaced vertically and horizontally. It has a structure in which the sealing part is cut and separated.

[Configuration of guillotine cutting]
The cutter unit 1 according to the embodiment is a sliding joint that connects the upper blade unit 2 and the lower blade unit 3 so as to be movable back and forth, and supports the blade edges 11 and 19 of the upper blade 10 and the lower blade 18 so that the distance between them can be changed. A sliding guide unit (intermediate member) 21, and an upper blade crank unit 27 and a lower blade crank unit 33 that move the upper blade unit 2 and the lower blade unit 3. The guillotine type cuts the horizontal seal of the continuous package by moving the respective cutting edges 11 and 19 against each other back and forth while pressing the cutting edge 11 of 10 against the blade back surface of the lower blade 18 fixedly mounted at a horizontal position. is a cutter.

The connector 5 mounting surface of the connector base plate 12 and the blade back surface of the lower blade 18 are both horizontal due to the slide guide unit 21, and are mounted on the swivel shaft 8 incorporated horizontally with the surface of the connector base plate 12 via the connector 5. The upper blade holder 9 and the blade edge 11 of the upper blade 10 mounted thereon are mounted so as to be vertically swingable while maintaining the state in which the blade edge 11 is parallel to the blade back surface of the lower blade 18 .

A compression coil spring 7 is set in a plurality of blind holes 5a above the central position of the turning shaft 8 of the connector 5, and one end of the spring 7 is in contact with the upper blade holder 9, and the repulsive force of the compression spring 7 makes the blade tip 11 of the upper blade downward. It is pressed against the blade back surface of the blade 18 .

When the blade rear surface of the upper blade 10 is in close contact with the blade rear surface of the lower blade 18 in a horizontal state, the sliding surface of the blade edge is below the center position of the swivel shaft 8 .

When the upper blade 10 and the lower blade 18 move back and forth against each other, the cutting edge 11 of the upper blade 10, which can swing up and down, slides while being pressed against the blade back surface of the lower blade 18 by the repulsive force of the compression coil spring 7. Therefore, at the point where the cutting edge 11 of the upper blade 10 and the cutting edge 19 of the lower blade 18 coincide with each other, the edge of the lateral seal of the continuous package 40 is bitten and cut. After the cutting ends with the advance of the blade edges 11 and 19, after reaching the respective advance ends, they retreat and return to their original positions.

The cutting edge 11 of the upper blade 10 is a straight line perpendicular to the moving direction, and the cutting edge 19 of the lower blade 18 has a shear angle (cutter unit 1, the distance between the lower blade 18 and the upper blade 10 increases toward the near side of the blade 1).

The blade shapes of the upper blade 10 and the lower blade 18 are a flat blade with a flat back surface (the cut end is straight) and a wavy blade with a V-groove processing on the back surface of the blade that matches the direction of sliding movement (the cut end is straight). waveform) can be used. FIG. 1 shows a wavy blade.

[Construction of a rotary cutter unit composed of a crank arm and an intermediate joint having a sliding joint that can move back and forth]
The upper blade unit 2 including the upper blade shaft holder 4 and the lower blade unit 3 including the lower blade shaft holder 15 form an intermediate joint connected by a sliding guide unit 21 which is a sliding pair capable of back and forth movement at the intermediate portion thereof. , an upper blade crank arm 23 and a lower blade crank having the same rotational radius R, respectively, with an upper blade crank shaft 22 and a lower blade crank shaft 28 rotatably incorporated in the upper blade shaft holder 4 and the lower blade shaft holder 15 as a pair of rotation. A rotary cutter unit 50 is configured by connecting with the arm 29 .

The upper blade drive shaft 24 and the lower blade drive shaft 30 are fixed at a position radially separated by a length R from the fixing positions of the upper blade crank shaft 22 and the lower blade crank shaft 28. The drive shafts 24 and 30 are rotatably supported by bearings 25 and 31, respectively.
The distance between the center of the drive shaft 24 and the center of the drive shaft 30 is a fixed joint, the left and right crank arms are a drive joint, and the upper blade unit 2 and the lower blade unit, which are connected by a sliding pair of the sliding guide unit 21, are intermediate joints. For example, the rotary cutter unit 50 is a four-bar link.

An upper blade drive pulley 26 and a lower blade drive pulley 32 are mounted on the opposite side of the upper blade drive shaft 24 and the lower blade drive shaft 30 from the mounting positions of the crank arms 23 and 29, and are controlled via a rotation transmission mechanism (not shown). A motor (an example of a "driving source") is connected, and by rotating the respective drive shafts 24 and 30 in opposite directions, the crank arms 23 and 29 are also rotated in opposite directions. The control motor has a rotation speed control section (not shown), which controls the rotation speed of the crank arm. In addition, the rotation speed of the crank arm is based on rotating at N rpm corresponding to the input speed of N pieces/minute in order to correspond the rotation angle for one rotation to the operating time.

2 and 3 are diagrams showing the layout dimensions of each part of the rotary cutter unit 50. FIG.

As shown in FIG. 2, in the rotary cutter unit 50, the stroke range of the sliding guide unit 21, which is a sliding pair of the intermediate joint, is set to be four times or more the radius R of the crank arm. and the lower blade drive shaft 30 is L (fixed joint). -2 x R". In other words, by setting the amount of expansion and contraction of the intermediate joint to be four times the radius of the crank arm, the upper blade crank arm 23 and the lower blade crank arm 29 can rotate continuously without rotation limitation.

The upper blade drive shaft 24 and the lower blade drive shaft 30 are arranged on a horizontal line at the same height, and the width center lines of the upper blade crank arm 23 and the lower blade crank arm 29 are arranged at the rotation start positions of the crank arms 23 and 29. The horizontal line connecting the center positions of the blade drive shaft 24 and the lower blade drive shaft 30 is aligned, and at the same time, the rotation start position of the upper blade crankshaft 22 is outside the center of the upper blade drive shaft 24 and the rotation start position of the lower blade crankshaft 28. are arranged at symmetrical positions outside the lower blade drive shaft 30 (the upper blade crank arm 23 and the lower blade crank arm 29 are outwardly symmetrical with respect to the intermediate position between the upper blade crankshaft 22 and the lower blade crankshaft 28). position is the rotation start position).

In the arrangement configuration described above, at the rotation start position of the upper blade crank arm 23 and the lower blade crank arm 29, the intermediate joint composed of the slide pair of the sliding guide unit 21, the upper blade unit 2 and the lower blade unit 3 is horizontal. It becomes a state where it is arranged on the left and right.

The left and right crank arms (upper blade crank arm 23, lower blade crank arm 29) rotate horizontally and outwardly symmetrically from the start position, and rotate the upper blade drive shaft 24 and the lower blade drive shaft 30 in opposite directions at the same rotational speed. When driving, the upper blade crank arm 23 is rotated clockwise and the lower blade crank arm 29 is rotated counterclockwise. The cutting edge 11 of the lower cutting edge 18 and the cutting edge 19 of the lower cutting edge 18 repeatedly approach, overlap (meaning advance of meshing, maximum meshing, retreat of meshing), and separation.
As shown in FIG. 3, the rotation angle of the upper blade crank arm 23 is 0° from the rotation start position, and rotates clockwise through 90°, 180°, and 270°. is rotated counterclockwise by 90°, 180°, and 270° from the rotation start position of 0°, and rotates in the opposite directions, but the rotation angle from the start has the same angle value. Therefore, the rotation angle of the crank arm described hereinafter is common to the upper blade crank arm 23 and the lower blade crank arm 29 .

When the upper blade crank arm 23 is driven clockwise and the lower blade crank arm 29 is driven counterclockwise at the same rotational speed, the center of the upper blade crankshaft 22 and the center of the lower blade crankshaft 28 are both located in the circle of radius R. Circular motion in the opposite direction along the trajectory.
Since the upper blade unit 2 and the lower blade unit 3, which constitute the intermediate joint, are connected by the sliding guide unit 21 of the sliding pair, each part of the upper blade unit 2 moves in the same clockwise direction as the center of the upper blade crankshaft 22. , and each part of the lower blade unit 3 rotates counterclockwise with the center of the lower blade crankshaft 28 with a radius R. That is, the cutting edge 11 of the upper blade 10, which is a constituent part of the upper blade unit 2, moves in the same circular motion as the center of the upper blade crankshaft 22, and the cutting edge 19 of the lower blade 18, which is a constituent part of the lower blade unit 3, moves along the lower blade crankshaft. It has the same circular motion as the center of the axis 28 .

The radius of rotation of the upper blade crank arm 23 and the lower blade crank arm 29 is R, the dimension from the upper blade crankshaft 22 to the upper blade tip 11 is CU, and the dimension from the lower blade crankshaft 28 to the lower blade tip 19 is As CD, the distance between the fixed joints (the distance between the centers of the drive shafts 24 and 30) is L, and "CU+CD>L-2×R".

In this way, when the crank arms 23, 29 are horizontal with respect to the drive shafts 24, 30 (when the length of the intermediate joint is at maximum L+2×R), the cutting edges of the upper blade 10 and the lower blade 18 11, 19 is "β=L+2×R−(CU+CD)". On the other hand, when the crank arms 23 and 29 are horizontal with respect to the drive shafts 24 and 30, the interval between the cutting edges is "α=CU+CD-(L-2×R)=4×R-β". , the cutting edges 11 and 19 of the lower cutting edge 18 are overlapped to form a meshing allowance α.

Due to this meshing allowance α, the trajectories of the rotational motion of the cutting edges 11 and 19 of the upper blade 10 and the lower blade 18 form an intersection between the rotation angles of the crank arms 23 and 29 between 90° and 180°. As the rotation of the crank arm progresses, the overlap between the cutting edges 11 and 19 increases, and the overlap reaches its maximum at the 180° position (maximum overlap amount α). After the rotation angle of 180°, the overlap gradually decreases, and at the second intersection between the rotation angles of 180° and 270° of the crank arms 23 and 29, the overlap of the blade edges disappears, and the blade edges 11 and 19 I'm going away.

The engagement margin α is set to be larger than the retraction amount M=B×tan ψ of the lower blade 18 determined by the shear angle ψ of the lower blade 18 and the blade width B.

[Rotational Motion of Upper Blade 10 and Lower Blade 18]
FIG. 4 shows a motion analysis diagram of the cutting edges 11 and 19 of the upper blade 10 and the lower blade 18. As shown in FIG.

As shown in FIG. 3, when the crank arms 23 and 29 rotate in opposite directions at equal speeds from the origin of the rotation angle θ=0°, the upper blade shaft holder 4 and the lower blade shaft connected to the crank shafts 22 and 28 are rotated. The rotary cutter unit 50 constructed between the holders 15 is guided in the longitudinal direction by the slide guide unit 21, and the center of the crankshaft 22 and the center of the crankshaft 28 rotate in opposite directions to form the rotary cutter unit. 50 length stretches from "L+2×R" to "L-2×R".
As shown in FIG. 4, the extension and contraction of the length of the rotary cutter unit 50 rotates the cutting edge 11 of the upper blade 10 and the cutting edge 19 of the lower blade 18 in synchronism with the crankshafts 22 and 28. The interval expands and contracts from “{L+2×R−(CU+CD)}=4×R−α” to “{L−2×R−(CU+CD)}=−α”. However, from the condition "CU+CD>L-2×R", α (overlap margin of cutting edge)=(CU+CD)-(L-2×R).

When the crank arms 23 and 29 of the upper blade 10 and the lower blade 18 rotate once, the upper blade unit 2 and the lower blade unit 3 move along the guide wheel 14 of the sliding guide unit 21 so that the upper and lower surfaces of the lower blade guide bar 20 are aligned. Since they are sandwiched, a horizontal state is maintained, and while the blade back surfaces of the upper blade 10 and the lower blade 18 are kept in close contact, the blade edges 11 and 19 move in circular motion with a radius R while the blade edge spacing approaches and separates. (The cutting edge 11 of the upper blade 10 rotates in a clockwise circular motion, and the cutting edge 19 of the lower blade 18 rotates in a counterclockwise circular motion.)

The center of the circular motion of the cutting edge 11 of the upper blade 10 is the distance from the center of the upper blade crankshaft 22 to the cutting edge 11 ( _A0 point) of the upper blade 10 at the origin of the rotation angle θ of the crank arm 23 = 0°. CU" in the blade edge direction (point O), and the center of the circular motion of the blade edge 19 of the lower blade 18 is the lower blade crankshaft at the origin of the rotation angle θ of the crank arm 29 = 0°. 28 to the cutting edge 19 ( _B0 point) of the lower blade 18, and is at a position (P point) advanced by "R" in the cutting edge direction.

At the origin where the rotation angle of the crank arms 23 and 29 is θ=0°, the distance between the cutting edges 11 and 19 is "D=4×R−α", and the distance between the centers of circular motion of the cutting edges is J=2×R. -α, and the locus circle U of the circular motion of the cutting edge 11 of the upper blade 10 and the locus circle K1 of the circular movement of the cutting edge 19 of the lower blade 18 intersect at two points above and below the center line along which the continuous package 40 is conveyed.

The upper intersection point (S point) is the engagement start position (shear cutting start position), and the lower intersection point (F point) is the engagement end position. (in engagement state), indicating that shear cutting is possible between the engagement start position and the maximum engagement position of the cutting edges.

[Movement of Cutting Edge 11 of Upper Blade 10 and Cutting Edge 19 of Lower Blade 18]
From the origin position where the rotation angle of the crank arms 23 and 29 is θ=0°, the cutting edge 11 of the upper blade 10 and the cutting edge 19 of the lower blade 11 start circular motion clockwise and counterclockwise at the same speed.

When the respective crank arms rotate at equal speeds in opposite directions, the upper blade shaft holder 4 and the lower blade shaft holder 4 connected through the crankshafts 22, 28 fixed to the crank arms 23, 29 of the upper blade 10 and the lower blade 18, respectively. Since the blade shaft holder 15 is always at the same height, the rotary cutter unit 50 maintains a horizontal state and the blade edge distance between the upper blade and the lower blade approaches at 0° to 180°, and at 180° to 360°. estrange.

When the rotation angle is 90°, the cutting edges 11 and 19 are at the top dead center position (maximum height position). The meshing (shear cutting) starts at the intersection point (S point) of the 19 locus circles K1.

Due to the shear angle ψ of the cutting edge 19 of the lower blade 18, the distance between the cutting edge 11 and the cutting edge 19 increases as the distance from the front plate 34 increases. do. If B is the maximum cutting edge width inside the corner portions at both ends of the lower blade 18 and ψ is the shear angle, the position where the cutting edge 11 and the cutting edge 19 first mesh is point S (the meshing position on the side closest to the front plate 34). position). The position where the cutting edge 11 and the cutting edge 19 finally mesh due to the inclination of the cutting edge line due to the shear angle ψ is point E (the meshing position farthest from the front plate 34). , M=B×tan ψ. In order to evaluate the state of engagement between the cutting edge 11 and the cutting edge 19, the cutting edge 19 plots a locus circle K1 of the circular motion of the S point and a locus K2 of the circular motion of the E point. Note that the center point of the circular motion of the locus circle K2 is located at a position shifted rightward by M from the center point of the locus circle K1.

After point S at which meshing starts, shear cutting progresses along the cutting edge line due to the shear angle of the cutting edge 19 while the meshing height position descends. Cutting is completed at point E where the locus circle K2 of the cutting edge 19 intersects.

After cutting, the overlap of the cutting edges 11 and 19 further progresses, and at the position of 180° of rotation angle, the cutting edges 11 and 19 are on the same straight line as the starting position, and the overlap of the cutting edges 11 and 19 is maximized.

When the rotation angle exceeds 180°, the cutting edges 11 and 19 descend below the straight line of the starting position, the meshing margin decreases, and the locus circle U of the cutting edge 11 of the upper blade 10 and the shear of the lower blade 18 The meshing state of the cutting edges 11 and 19 is canceled at point F where the trajectory circle K1 of the cutting edge at the starting point intersects.

When the rotation angle is 270°, the cutting edge is at the bottom dead center position (lowest height position).

After the rotation angle reaches 270°, the distance between the cutting edges 11 and 19 increases while increasing, and returns to the original maximum distance at the 360° position.

While shear cutting is performed in the section where the upper blade 10 and the lower blade 18 engage with the upper blade 10 and the lower blade 18 at a rotation angle of 90° to 180° (from the point S to the point E on the locus circle U), the blade edges 11 and 19 are moved by the crank arms 23 and 29. is descending at a speed based on the circular motion caused by the rotation of That is, if the descending speed of the circular motion and the conveying speed of the continuous package are matched, the continuous package can be cut without stopping.

For the details of the motion of the cutting edges 11 and 19, refer to the following "Non-stop operation without stopping the reciprocating motion of the cutter and the conveying of the continuous package".
[Non-stop operation without stopping the reciprocating motion of the cutter and the transport of the continuous package]

As shown in FIG. 4, while the crank arms 23 and 29 of the upper and lower blades 10 and 18 respectively make one revolution in opposite directions, the cutting edges 11 and 19 of the upper and lower blades follow their locus circles U and K1 respectively. , K2.

Since the cutting edge 11 of the upper blade 10 is a straight line, the movement of the cutting edge is the same at any position in the blade width direction and can be indicated by a locus circle U.

Since the cutting edge 19 of the lower blade 18 has a shear angle, the trajectory of the cutting edge 19 has two trajectories, a trajectory circle K1 at the position where the shear starts and a trajectory circle K2 at the position where the shear ends.

When the center of the trajectory circle U of the cutting edge 11 of the upper blade 10 is O, the center of the trajectory circle K1 of the shear start point of the cutting edge 19 of the lower blade 18 is P, and the center of the trajectory circle K2 of the shear end point is Q, OP If the length between them is "D=4×R−α", the locus circle U of the upper blade and the locus circle K1 of the lower blade have an overlap margin α.

Since the cutting edge 19 of the lower blade meshes with the cutting edge 11 of the upper blade 10 from the shear start position 19a to the shear end position 19b, the overlap margin α is M=B×tanψ (B: from the shear start point to the shear end point The condition is that it is larger than the blade width dimension, ψ: shear angle).

The crank arm 23 of the upper blade 10 rotates clockwise, and the crank arm 29 of the lower blade 18 rotates counterclockwise. can be done.

The points of intersection of the locus circle U and the locus circle K1 are point S above the horizontal line and point F below the horizontal line.

After the meshing of the cutting edges starts at the upper intersection point S of the locus circles U and K1, the overlap of the cutting edges of the upper blade 10 and the lower blade 18 ends at the lower intersection point F of the locus circles U and K1.

At this time, after the cutting edges 11 and 19 start to mesh at the upper intersection point S of the locus circles U and K1, the cutting edges of the upper blade 10 and the lower blade 18 shear cut at the upper intersection point E of the locus circles U and K2. will do.

That is, the cutting edges 11 and 19 start overlapping at the S point, shear cut from the S point to the E point, and continue to move downward until the overlap is completed at the F point.

When the cutting edge 11 and the cutting edge 19 move downward from point S to point F, after matching the cutting edge descending speed with the conveying speed of the continuous package 40 at point S, the cutting edge 11 moves up to point F where the overlap is completed. By synchronizing the descending speed of the cutting edge 19 and the conveying speed of the continuous package 40, the reciprocating motion of the cutting edge 11 of the upper blade unit 2 of the rotary cutter unit 50 and the cutting edge 19 of the lower blade unit 3 and the movement of the continuous package 40 The movement in the vertical direction means that the continuous package 40 moves downward while shear-cutting the laterally sealed portion. Therefore, in the conventional guillotine cutter, which has only a simple horizontal reciprocating motion, the conveying of the continuous package 40 had to be stopped during shear cutting, but in the rotary cutter unit 50 of the present invention, the horizontal motion of the cutting edge and the vertical motion of the continuous package 40 can be realized at the same time.

In order to make the installation space of the rotary cutter unit 50 compact, the trajectory circle radius R of the cutting edges 11 and 19 is made as small as possible. By the way, the descending speed of the cutting edges 11 and 19 during the overlapping period of the cutting edges 11 and 19 is rate-determined by the vertical velocity of the circular motion of the cutting edges. Since the trajectory circle radius of the cutting edge is small, when the continuous package is conveyed at high speed, the descending speed of the cutting edge is slower than the conveying speed of the continuous package. For this reason, the conveying speed of the continuous package 40 during the non-overlapping period must be higher than the synchronous speed (the lowering speed of the cutting edge) in the overlapping section of the cutting edge.

The continuous package 40 has a content portion with a maximum thickness of about 15 mm and a horizontal seal portion with a thickness of less than 1 mm. As the spacing between the cutting edges 11, 19 of the blade 10 and the lower blade 18 is enlarged or reduced, contact between the core and the cutting edge must be avoided. Therefore, the conveying speed of the continuous package 40 is controlled according to the concept described below.

While the blade edges 11 and 19 of the upper blade 10 and the lower blade 18 overlap each other, the lowering speed of the blade edges 11 and 19 and the conveying speed of the continuous package 40 are synchronized. The cutting edge position moves together with the thinnest laterally sealed portion of the continuous package 40 .

After the cutting edges 11 and 19 of the upper blade 10 and the lower cutting edge 18 have completely overlapped, the gap between the cutting edges is first widened before passing through the core. (near the θ=270° position), the conveying speed of the continuous package 40 is gradually increased.

When the blade edges 11 and 19 of the upper blade 10 and the lower blade 18 return to the initial position (θ = 0°) and the blade edge spacing narrows again, the gap between the blade edges 11 and 19 interferes with the inner part, so θ = 90°. By gradually slowing down the conveying speed of the continuous package 40 from the vicinity, the advance of the content portion is retarded.

At the S point where the cutting edges 11 and 19 start to mesh, the conveying speed of the continuous package 40 is matched with the descending speed of the cutting edges 11 and 19 at the S point.

[Reason for applying the configuration of the cutter unit with built-in spring to the rotary cutter unit]
The cutter unit employed in the conventional slider-crank mechanism disclosed in Japanese Patent Application Laid-Open No. 2004-223679 has a lower blade that is lifted in the direction of the upper blade by a tension spring, and is attached to the back surface of the fixed upper blade. It is configured to be pushed.

In this configuration, the parts such as the spring hook and the lower blade lifting guide protrude from the top and bottom surfaces of the upper and lower blades. The position of the chute attached to the lower side must be separated from the current situation, and compatibility with the existing small bag injection device will be lost.

In addition, since the lower blade is lifted up against its own weight, the pressing force of the upper blade against the blade back surface is reduced by its own weight. When the upper blade unit 2 and the lower blade unit 3 are rotated, the blade edges overlap and when cutting the horizontal seal portion of the continuous package, downward acceleration acts on the lower blade unit 3. The pressing force generated by the lifting action of the spring is further reduced, and the cutting performance is further reduced (cutting becomes impossible if a gap is formed between the back surfaces of the blades that are in close contact with each other during high-speed rotation).

On the other hand, in the rotary cutter unit 50 according to the embodiment of the present invention, the lower blade 18 is fixed and the upper blade 10 swings and rotates due to the action of the compression coil spring 7 so that the blade back surface of the lower blade 18 is rotated. Therefore, the downward acceleration generated when the cutting edges 11 and 19 overlap acts in the direction of increasing the pressing force of the cutting edge 11 of the upper cutting edge.

In addition, since the compression coil spring 7 is inserted into a hole machined in the connector 5 to be attached to the upper blade shaft holder 4, there are no parts protruding from the upper and lower surfaces of the upper blade 10 and the lower blade 18. It is possible to keep the movable range within the built-in range of the parts of the existing cutter unit, and it is possible to attach it to the cutter unit part of the existing small bag inserter.

[Falling of the cut pouch]
In the rotary cutter unit 50 of the embodiment, the upper blade unit 2 and the lower blade unit 3 connected by the extendable slide guide 21 descend between 90° and 180° (between point S and point F). At this time, the cutting edges 11 and 19 are meshed to perform guillotine cutting.

At the start of engagement, i.e., the start of cutting of the horizontal seal of the continuous package 40 (point S), the conveying speed of the continuous package 40 is matched with the lowering speed of the upper blade 10 and the lower blade 18, and the cutting completion position or the engagement end. The descending speed of the cutting edges 11 and 19 and the conveying speed of the continuous package 40 are synchronized to the position.

At the end of cutting, the sachets separated and cut from the leading end of the continuous package 40 fall freely with the initial velocity being the descending speed of the continuous package at the end of cutting (point E).

[2. action]
The operation of the cutter unit of the embodiment will be described in (1) to (10) below.
(1) The alignment adjustment between the cutting edge 11 of the upper blade 10 and the blade back surface of the lower blade 18 and the adjustment of the sliding guide unit 21 are independent.
The upper blade unit 2 and the lower blade unit 3 are connected by a sliding joint (sliding guide unit 21), and each unit serves as an intermediate joint that can extend and contract while maintaining horizontality.

The upper blade crankshaft 22 and the lower blade crankshaft 28, which are rotatably inserted into the upper blade shaft holder 4 and the lower blade shaft holder 15 at both ends of the intermediate joint, are attached to the upper blade crank arm 23 and the lower blade crank arm 29. Since the crank units 27 and 33 of the fixed upper blade 10 and the lower blade 18 have the property that the middle joint expands and contracts, the respective crank arms can be continuously rotated in opposite directions.

The rotation starting positions of the crankshafts 22 and 28 fixed to the respective crank arms 23 and 29 are arranged at symmetrical positions with respect to the upper blade drive shaft 24 and the lower blade drive shaft 30. , 30 are made equal, when the crank arms 23 and 29 are reversely rotated at the same speed, the middle joint composed of the upper blade unit 2 and the lower blade unit 3 is always kept horizontal, and the overall The vertical movement is repeated, and the upper blade 10 at the tip of the upper blade unit 2 and the lower blade 18 at the tip of the lower blade unit 3 oppose each other and repeat the back-and-forth motion.

The cutting edge 11 of the upper blade and the cutting edge 19 of the lower blade both circularly move in the opposite direction with the same radius, and the rotation angle of the crank arm moves downward from above between 90° and 270°. 19 overlaps, so that if there is a lateral seal of the continuous package 40 between the cutting edges 11 and 19, shear cutting is performed.

In the area where the blade edges 11 and 19 overlap, by synchronizing the conveying speed of the continuous package with the downward movement speed of the blade edges, the movement of the continuous package in the vertical direction and the opposing movement of the blade edges in the horizontal direction can be achieved. We were able to realize continuous motion without interference.

The sliding contact between the back surface of the upper blade 10 and the back surface of the lower blade 18 is performed by the compression coil spring 7 incorporated in the connector 5 against the back surface of the lower blade 18 fixed to the lower blade shaft holder 15 . This is realized by pressing the cutting edge 11 of the upper blade which swings and rotates downward due to the repulsive force. The horizontality of the sliding guide unit 21 of the upper blade unit 2 and the lower blade unit 3 is determined by the guide ring 14 of the upper blade guide mounting plate 13 fixed to both end surfaces of the connector base plate 12 of the upper blade unit 2 and the lower blade 18. This is realized by a combination of lower blade guide bars 20 fixed to both end surfaces of the horn portion 18a. Therefore, the sliding adjustment between the cutting edge 11 of the upper blade 10 and the blade rear surface of the lower blade 18 can be performed separately from the adjustment for rolling the guide wheel 14 on the upper and lower surfaces of the lower blade guide bar 20 without backlash. ing.

(2) The positions and velocities of the cutting edges of the upper and lower blades can be analyzed using circular motion equations. (Also explained in (3))
The acceleration reduction effect of the rotary cutter unit of the present invention will be verified using equations representing the motion of the cutting edges of the upper blade 10 and the lower blade 18 . The circular motion of the cutting edge 11 and the cutting edge 19 is the same as the circular motion of the crankshafts 22 and 28 due to the rotation of the left and right crank arms. The circular motion of the cutting edge starting from a rotation angle of 0° shown in FIG. 19 increases in the counterclockwise direction), the angle θ used in the equations representing the motion (position, velocity) of the cutting edge will be the same.

4A and 4B are diagrams for explaining the motion of the cutting edge 11 of the upper blade and the cutting edge 19 of the lower blade.

The origin of the X-axis and the Y-axis in FIG. 4 is the position of the center of rotation of the upper blade 10, and the rightward direction of the X-axis is "+", and the upward direction of the Y-axis is "+".

The cutting edge 11 of the upper blade circularly moves around the point O, the shear start position 19a of the cutting edge 19 of the lower blade moves around the point P, and the shear end position cutting edge 19b around the point Q, respectively, with a radius R.

The center-to-center distance between OPs is J=2×R−α, where α is the meshing allowance.

Since the cutting edge 19 of the lower blade has a cutting edge inclination of a shear angle ψ, the center point Q of the circular motion at the shear end position is located to the right of the rotation center P point at the shear start position by M=B (cutting width)×tan ψ. .

The rotation start position of the cutting edge 11 of the upper blade 10 is defined as the origin of the cutting edge 11 (point Ao), and the rotation start position of the shear start cutting edge position of the cutting edge 19 of the lower blade 18 is defined as the origin (point Bo). The positions and velocities of points A and B and point C, which is the position of the edge of the cutting edge at the end of shear of the cutting edge of the lower cutting edge 19, when the cutting edge 19 is rotated by an angle θ in the opposite direction can be obtained by the following equations.

In the following, positions are represented by X, Y coordinates (X~, Y~), and velocities are represented by X, Y direction components: (V~X, V~Y). The rotation angle θ (rad) of the crank arm is obtained by θ=ω×t using the angular velocity ω (rad/sec) at the center position of the crankshaft and the time t (sec) from the rotation start position.

[Position of point A (XA, YA) and velocity (VAX, VAY)]
(XA, YA) = (-R cos θ, R sin θ) Equation (1)
(VAX,VAY)=(ωRsinθ,ωRcosθ) Equation (2)

[Position (XB, YB) and velocity (VBX, VBY) of point B]
(XB, YB)=(J+R cos θ, R sin θ) Equation (3)
(VBX, VBY)=(-ωRsinθ,ωRcosθ) Equation (4)

[Position (XC, YC) and speed (VCX, VCY) of the cutting edge retraction end due to the shear angle of the lower blade 18]
(XC, YC)=(J+M+R cos θ, R sin θ) Equation (5)
(VCX, VCY)=(-ωRsinθ,ωRcosθ) Equation (6)

[Note]
From equations (1), (3), and (5), the position of the cutting edge in the Y direction is the same (R sin θ), so the position in the Y direction is represented by the following equation (7).
Y=R sin θ Expression (7)

Further, since the velocities of the cutting edge in the Y direction are all the same according to equations (2), (4), and (6), the Y direction velocity is expressed as the following equation (8).

Vy(θ)=ωRcosθ Equation (8)

From the start positional relationship between the upper blade 10 and the lower blade 18, the rotation angle θs of the drive shafts 24 and 30 at the meshing start position S and the rotation angle θe of the crank arms 23 and 29 at the cutting end position E, then , the height position Ys of the cutting edge and the descending speed Vs, and the height position Ye of the cutting edge at the angle θe and the descending speed Ve.

Further, the angle θf, the descending speed Vf, and the height Yf of the cutting edge at the point F where the upper blade and the lower blade finish meshing are assumed.

However, ω can be obtained by ω=πN/30 (rad/sec), where N (rpm) is the rotational speed of the drive shaft.

(3) Find the positions and speeds at which the cutting edges 11 and 19 of the upper blade 10 and the lower blade 18 start and end meshing, and the time from the start to the end of cutting.
4, the rotational angle .theta.s of the drive shaft at the engagement start position of the cutting edges 11 and 19 of the upper and lower blades can be obtained from XA=XB in equations (1) and (3).

-R cos θ = J + R cos θ ⇒ θs = arccos {-J/(2R)} Equation (9)
(Note) The negative angle "-θs" of "θs" obtained from formula (9) is the angle at point F when meshing is complete. If the direction of the angle is the same, "-θs" is written as "θf = 2π-θs"

The cutting edge position (height) and the descent speed at point S at the start of meshing (cutting) and point F at the meshing end position are Y=R sin θ in equation (7) and Vy(θ)=ωR cos θ in equation (8). can be obtained by substituting θs or θf into .

Point S: Ys=Rsinθs Equation (10)
Vy(.theta.s)=Vs=.omega.Rcos.theta.s Expression (11)
Point F: Yf=Rsin (2π-θs) Equation (12)
Vy(θf)=Vf=ωRcos(2π-θs) Equation (13)

・Obtain the rotation angle θe of the crank arm at the cutting end position E, the cutting edge position (height) Ye, and the descent speed Vy (θe).

From XA=XC, -Rcosθ=J+M+Rcosθ
θe=arccos{−(J+M)/(2R)} Equation (14)

The position of the cutting edge at point E and the descent speed can be obtained by substituting θe for Y=R sin θ in equation (7) and Vy(θ)=ωR cos θ in equation (8).
E point: Ye=R sin θe Equation (15)
Vy(θe)=Ve=ωRcosθe Equation (16)

The descending amounts δse, δsf and the times Tse, Tsf of the cutting edge from the engagement start (cutting start) point S to the cutting end point E or the engagement completion point F are obtained as follows.

δse=Ys-Ye Expression (17)
δsf=Ys-Yf Expression (18)
Note: From FIG. 4, Ys>Ye, Yf.

The rotation angle Δθ during the cutting period or the meshing period is
Δθse=θe−θs Equation (19)
Δθsf=θf−θs Equation (20)

Disconnection time Tse (sec), engagement time Tsf (sec)

Tse=Δθse×Ts/(2π)=(θe−θs)×Ts/(2π) Equation (21)
Tsf=Δθ×Ts/(2π)=(θf−θs)×Ts/(2π) Equation (22)

However, Ts is the cycle time, and if the rotation speed of the drive shaft is N (rpm), Ts = 60/N (sec) Equation (23)

・The time Tp other than the cutting period and the time Tq other than the meshing period are
Tp=Ts-Tse={2π-(θe-θs)}×Ts/(2π) Equation (24)
Tq=Ts-Tsf={2π-(θf-θs)}×Ts/(2π) Equation (25)

(4) How to determine the conditions for continuous operation without stopping the transportation of continuous packages.
a) At point S where the shear cutting is started, the continuous package conveying speed (from top to bottom) is matched with Vy(θs)=Vs=ωRcosθs in Equation (11), which is the downward speed of the cutting edge.

If the cutting edge descending speed and the continuous package conveying speed do not match at the start of cutting, the cutting line at the cutting start position does not form a straight line perpendicular to the vertical seal, resulting in a tearing state.

b) Ideally, the lowering speed Vp2 of the continuous package is synchronized with the lowering speed Vy(θ) of the cutting edge of the equation (8) until point E where the shear cutting ends or point F where meshing is completed.

When synchronized with the lowering speed Vy (θ) of the cutting edge, the change in the lowering speed Vp2 of the continuous package is controlled by the lowering speed of the upper and lower blades when the rotation angle θ of the crank arm is in the range of θs ≤ θ ≤ θe or θf. It can be obtained from Vy(.theta.)=.omega.R cos .theta. using the velocity equation (8).
(The lowering speed of the cutting edge and the conveying speed of the continuous package are synchronized from the start of engagement to the completion of cutting or engagement.)

c) The amount of descent of the cutting edge δse or δsf during the cutting period or meshing period can be obtained by formula (17) or (18).
How to find the required time other than the synchronous period when the conveying speed of the continuous package is synchronized with the descent speed of the cutting edge from the start to the end of meshing. Since it is part of the conveying amount P for one pitch of the continuous package, it is sufficient to convey (P-δsf) during the period other than the meshing period. That is, if the rotation angle difference in the meshing period is <Δθcf (20)>, the driving angle for sending P-δsf is (2π-Δθsf), and if the cycle time is Ts, the required time is tq can be expressed by equation (26).
tq=(2π−Δθsf)×Ts/(2π) Equation (26).

d) The conveying speed Vp1 of the continuous package outside the shear cutting period can be expressed by the following formula (27).
Vp1=(P−δsf)/tq Equation (27)

e) The conveying speed of the continuous package is Vp1 from the rotational angle of the crank arms 23 and 29 to Θs. If Θf ~ 360° from the completion of synchronization and engagement until the end of one cycle is conveyed at Vp1 again, the conveyance of the continuous package can be synchronized with the rotary motion of the cutting edge at a constant rotation without stopping.
However, Θs (deg) = θs x 180/π, Θf (deg) = θf x 180/π

f) The conveying speed Vp1 during the overlapping period of the upper blade and the lower blade (from point S to point F) and the conveying speed Vp2 in other sections are not changed intermittently, but continuously with a transition section provided. change the speed dynamically.

g) From the vicinity of the crank arm rotation angle θ = 90° before point S, decelerate from Vp1 to Vp2, transport to point F at the transport speed Vp2 that matches the descending speed of the cutting edge at point S, and rotate from point F. The conveying speed is increased from Vp2 to Vp1 until the angle θ=270°.

In the cutter unit 1 of the embodiment shown in FIGS. 1 to 4, the crank radius R = 11 mm, the meshing allowance α = 8 mm, the maximum blade edge distance D = 36 mm, the distance between OPs J = 14 mm, the width of the lower blade B = 117 mm, The shear angle ψ = 2°, M = 117 × tan 2° = 4 mm, and the motion of the cutting edge was analyzed when cutting a pouch pitch P = 70 mm at 250 bags/min (crank rotation speed N = 250 rpm). The cycle time Ts=60/250=0.24 (sec). The analysis results are shown in the graph of FIG. 5, and the details will be described later.

For comparison, a cutter unit using a conventional slider-crank mechanism was examined with respect to the conveying speed of the continuous package and the acceleration at the time of starting and stopping.

In the case of the conventional guillotine type cutter that performs horizontal reciprocating motion, the reciprocating motion and the up-and-down motion of the continuous packaging body are alternately intermittently operated, and each motion time is 0.12 sec. When conveying a small bag with a pitch of 70 mm using a trapezoidal wave (acceleration/deceleration time is 25% of the operating time), the maximum speed is Vmax = 777.8 mm/sec and the maximum acceleration Amax = 25926 (mm/sec ² ). Ta. When such a large acceleration occurs, variations occur in the pitch measurement that serves as a reference for the cutting position, and in the transport stop position, which cannot be applied to actual operation.

On the other hand, in the cutter unit of the embodiment, how the conveying speed and acceleration of the continuous package are changed by continuous operation with the rotary cutter unit 50 having an extendable intermediate joint having a sliding pair. verified whether to

(5) Graph the movement of the cutting edges of the upper and lower blades to visually grasp the rotation angle of the crank and the progress of cutting.
Fig. 5 is a graph in which the cutting edge positions and cutting edge speeds of the upper blade 10 and the lower blade 18 are calculated from formulas (1) to (6), and the horizontal axis represents the rotation angle θ (0° to 360°) of the crank arm. It has become.

In FIG. 5, the curve of "upper blade edge position" is a graph obtained by expanding the locus circle U of point A of the blade edge 11 of the upper blade 10 shown in FIG. A locus circle K1 of the cutting edge 19a of the blade 18 and a curve of "lower blade shear end position" are graphs in which a locus circle K2 of the cutting edge 19b of the lower blade is developed.

Although each cutting edge moves back and forth, the horizontal axis is the rotation angle θ of the crank arm, and the X-axis numerical value is applied to the vertical axis of the graph. The circles K1 and K2 form a downwardly convex graph, and the intersection points of the respective graphs are the S point, the E point, and the F point.

The first intersection point S (131.2° to 0.0875 sec) of the graphs of "upper blade edge position" and "lower blade shear start position" is the position where the upper blade edge 11 and the lower blade edge 19a first mesh. , The first intersection point E (147.3° to 0.0982 sec) of the graphs of "upper blade edge position" and "lower blade shear end position" is the shear cutting end position (the position where the upper blade edge 11 intersects the lower blade edge 19b). ), and the second intersection point F (228.8° to 0.1525 sec) of the "upper blade edge position" and the "lower blade shear start position" is the end of the overlap between the upper blade edge 11 and the lower blade edge 19a. position.

The cutting edge descending speed Vs at point S (131.2°) is -189.8 mm/sec. The sign of velocity is "+" for upward and "-" for downward.

(6) A problem in synchronizing the speed Vp2 of the continuous package with the lowering speed Vy(θ) of the blade edge from the start to the end of engagement of the blade edge.
In Fig. 6, Vp2 = -189.8 mm/sec at points S and F during the period from point S (131.2°) to point F (228.8°) where the cutting edges 11 and 19 of the upper and lower blades overlap. , and during other periods, the conveying speed Vp2 of the continuous package is made to coincide with the lowering speed Vy (θ) of the cutting edge, and the conveying speed and the acceleration of conveying when conveying 1 pitch 70 of the small bag between 0° and 360° Show change.

When the acceleration/deceleration time for decelerating from Vp1 to Vp2 immediately before point S and increasing from Vp2 to Vp1 immediately after point F is 0.025 sec, the deceleration start angle from Vp1 to Vp2 is 94° (0.0625 sec). , Vp2 to Vp1 is 226° (0.1775 sec), so Vp1=-324.8 mm/sec.

At this time, the acceleration when decelerating from Vp1 to Vp2 is -5399mm/ ^sec2 , and the acceleration when accelerating from Vp2 to Vp1 is +5399mm/ ^sec2 , both smaller than the target 1G (9800mm/ ^sec2 ). Become.

In addition, if Vp2 is synchronized with the descending speed Vy(θ) of the cutting edge immediately after passing point S, the speed is accelerated to the 180° position and then decelerated toward point F, resulting in an acceleration of +5603mm/sec ² at point S. occurs, and an acceleration of -5603mm/ ^sec2 occurs at F point.

For this reason, the acceleration of the continuous packaging body generated a constant negative acceleration of -5399 mm/sec ² from 94° to 131.2° (point S), and after reversing to a positive acceleration of 5603 mm/sec ² at point S, the acceleration was After gradually decreasing to a negative acceleration of -5603 mm/sec ² at point F, a constant positive acceleration of 5399 mm/sec ² acts from 228.8° (point F) to 226°.

Therefore, the acceleration is reversed from "-" to "+" and from "+" to "-" at points S and F, the absolute value of the difference is 11002mm/ ^sec2 , and the acceleration change is 1G Exceed.

The maximum speed of intermittent transfer of the conventional guillotine type cutter is Vmax = 777.8mm/sec, maximum acceleration Amax = 25926mm/ ^sec. In this case, the inertial force is also reversed, which is not good for stable transportation of continuous packages. Therefore, another synchronization method is considered.

(7) Merit of conveying continuous packages from the start to the end of meshing with the cutting edge descending speed at the meshing start position.
In order to suppress changes in acceleration when conveying continuous packages, the cutting edge descending speed Vy (131.2°) at point S where the cutting edges of the upper and lower blades start to engage = -189.8 mm/sec at point F Consider transporting continuous packages at a constant speed to

Fig. 7 shows that during the period from point S (131.2°) to point F (228.8°) where the blade edges 11 and 19 of the upper and lower blades overlap, the conveying speed Vp2 of the continuous package is Descending speed Vy (θs) = Vy (θf) = Conveying at a constant speed of -189.8 mm/sec, when conveying a small bag at a pitch of 70 mm between 0° and 360°, changes in conveyance speed and acceleration of conveyance indicates

If the acceleration/deceleration time for decelerating from Vp1 to Vp2 immediately before point S and increasing from Vp2 to Vp1 immediately after point F is 0.025 sec, the angle at which deceleration starts from Vp1 to Vp2 is 94° (0.0625 sec). , Vp2 to Vp1 is 226° (0.1775 sec), so Vp1=-352.8 mm/sec.

A constant negative acceleration of -6520mm/sec ² occurs from 94° to 131.2°, and a constant positive acceleration of 6520mm/sec ² occurs from 228.8° to 226°, both of which are 1G or less (9800mm/sec ² or less). become.

Compared to intermittent transfer with an operation time of 0.12 sec, the acceleration is reduced to "about 1/4" of intermittent transfer Amax = 25926 mm/sec ² , and the maximum transfer speed is reduced to "intermittent transfer Vmax = 777.8 mm/sec". 1/2.2". Also, in the period from point S (131.2°) to point F (228.8°) where the blade edges of the upper and lower blades overlap, the conveying speed Vp2 of the continuous package is synchronized with the lowering speed Vy (θ) of the blade edge. Since there is no such reversal of acceleration, continuous packages can be conveyed stably.

Since the descending speed of the continuous package from point S to point F is constant (Vp2=-189.8mm/sec), it does not match the descending speed of the cutting edge Vy (θ) (θ=131.2° to 228.8°). not

However, even if there is a difference in speed, the speed Vp2 = -189.8mm/sec continues to descend since the time from point S where the blade edge starts to engage to point E where shear cutting is completed is very short. The cutting position of the horizontal seal part of the package and the position of the cutting edge descending at the speed Vy (θ) (θ = 131.2° to 228.8°) are very slight (the cutting edge is 0.3 mm ahead of the center position of the horizontal sealing part). , and there is no problem with cutting the horizontal seal while the continuous package is descending (details will be described in (8) of operation).

250 pcs/min, small bag pitch 70mm was studied, but it was verified that the transportation speed of continuous packages, which was the biggest problem in speeding up, was greatly reduced, and at the same time, the acceleration was also reduced. It can be seen that the effect of continuous operation with the reversing crank mechanism having an extendable intermediate joint is very large.

[Modification]
FIG. 8 shows a modified example in which the conveying speed between SFs is constant, the pitch of the pouches is 70 mm, and the operation is performed at 300 pouches/min.

In the modified example, the speed Vp1 is -430.1 mm/sec, the acceleration is -8094 mm/sec ² from 86° to 131.2°, and 8094 mm/sec ² from 228.8° to 274°, both of which are 1 G or less (9800 mm/sec ² below).

On the other hand, the intermittently driven continuous package transport drive time was 0.1 sec, the maximum speed was 933.3 mm/sec, and the maximum acceleration was 37333 mm/ ^sec . I was able to transport it well.

(8) When the descending speed of the continuous package is constant from point S to point F, verify the deviation between the horizontal seal cutting position and the lowering position of the cutting edge of the continuous package from the start of cutting to the completion of overlap.
In FIG. 7, the conveying speed Vp2=-189.8 mm/sec of the continuous package from the point S to the point F is constant, while the lowering speed Vy (θ) of the cutting edges of the upper and lower blades is - The speed increases from 189.8mm/sec to -288mm/sec at the 180° position (the position where the crank arm is half-rotated), then decelerates again to -189.8mm/sec toward F point.

Therefore, the horizontal seal cutting position of the continuous package from point S to point F gradually lags behind the position of the cutting edge.

However, in the graph of FIG. 7, from the cutting start point S to the cutting end point E, the lowering position of the cutting edge (upper-lower position curve of the cutting edge) and the lowering position of the continuous package (horizontal seal cutting position curve) almost coincide. , E, the cutting edge leads the transverse seal shear position by only 0.3 mm.

Although the 0.3 mm advance of the cutting edge from the cutting start point S to the cutting end point E causes the inclination of the cut line of the continuous package, the horizontal seal width is 7 to 10 mm, so the inclination does not pose a problem for the product.

In the graph of FIG. 7, after passing point E, the horizontal seal cutting position curve is located above the cutting edge vertical position curve, and the interval between them gradually widens. The positions of the cutting edges of the upper and lower blades are -8.27 mm with respect to mm, and the cutting edges are leading (the leading position of the cutting edge of the continuous package is behind the cutting edge position).

After passing point E, the blade edge overlaps up to point F, and when the cut edge of the horizontal seal of the continuous package is transported below the blade edge position, the cut edge of the horizontal seal collides with the back surface of the lower blade and jams. occurs. For this reason, delaying the cutting edge of the continuous package is rather convenient for avoiding interference with the cutting edge.

After passing point F, the conveying speed of the continuous package gradually increases and reaches Vp1 = -352.8 mm/sec at the position of 266°, but the descending speed of the cutting edge decreases rapidly, so the continuous package It coincides with the cutting edge position again around 267° where the acceleration of is completed.

However, at this position, the gap between the cutting edges 11 and 19 of the upper and lower blades is wide enough for the horizontal seal portion to pass through (the gap between the cutting edge position curve of the upper blade and the shear starting point position curve of the lower blade in FIG. 5). From this, it can be seen that there is a gap of 12 mm between the edges of the upper and lower blades), and there is no contact between the edges and the continuous package.
The speed control method for continuous operation without stopping both the conveyance (vertical movement) of the continuous packages and the horizontal movement of the cutter has been described in the embodiments. However, if the condition that the lowering speed of the cutting edge and the conveying speed of the continuous package are the same at the point S where the cutting edge starts to mesh, other than the embodiment, "Conveying the continuous package is operated at a constant speed without changing speed." , a control method for changing the rotation speed of the drive shaft of the crank unit,” and a control method for changing the rotation speed of the drive shaft of the crank unit at the same time as controlling the conveying speed to two speeds as in the embodiment. Various modifications can be made within the scope.

(9) Confirmation of interference between the cutting edge and the contents of the continuous package.
FIG. 9 shows the relationship between the blade edge and the lateral seal cutting position of the continuous package. In order to visualize the relationship between the horizontal seal position and the cutter position of the continuous package, the lower end position of the inner part (white ▽ mark) and the upper end position of the inner part (black ▲ mark) at various crank rotation angles are shown. . The horizontal seal extends from the upper end of the inner part to the lower end of the inner part. In this figure, the minimum dimension of a general horizontal seal is 14 mm.

When the rotation angle of the crank is from 0° to 73°, the cutting edge line (straight line connecting the cutting edge of the upper blade and the cutting edge of the lower blade) is below the upper edge of the contents, so the contents of the continuous package can be crossing. However, at 73° where the upper edge of the inner part exactly coincides with the cutting edge line position, the gap between the cutting edge of the upper blade and the cutting edge of the lower blade is shown in the graphs "Lower blade edge shear start position curve" and "Upper blade edge position curve". As shown in the interval of 17mm, the inner part (the maximum thickness of the inner part is about 15mm, and the thickness increases in a tapered shape at the upper end of the inner part) does not come into contact. At angles smaller than 73°, this gap widens further, so that between 0° and 73° the cutting edges of the upper and lower blades do not touch the core.

When the crank rotation angle is in the range from 73° to 267°, the cutting edge line (straight line connecting the cutting edge of the upper blade and the cutting edge of the lower blade) crosses the thinnest horizontal sealing part of the continuous package. I'm here. The gap between the cutting edge of the upper blade and the cutting edge of the lower blade on the cutting edge line at each rotation angle is indicated by the interval between the "lower blade edge shear start position curve" and the "upper blade edge position curve" in the graph. The interval between both curves gradually narrows from 73° to 131.2°, but since the continuous package descends at a speed exceeding this, the cutting edge line rapidly approaches the middle position (cutting position) of the horizontal sealing length. The cutting edges of the upper and lower blades do not come into contact with the contents.

Between 131.2° and 228.8° where the cutting edge of the upper blade and the cutting edge of the lower blade overlap, the conveying speed of the continuous package is a constant low speed section, so the cutting position is at the middle position (cutting position) of the horizontal sealing length. The existing cutting edge line gradually approaches the upper edge of the inner part, but it does not exceed the upper edge of the inner part, and the cutting edges of the upper and lower blades do not touch the inner part in this section.

From the position where the rotation angle of the crank arm exceeds 228.8°, the slope of the downward displacement of the curve indicating the cutting edge line position becomes gentle and reaches an inflection point at the 270° position. On the other hand, the conveying speed of the continuous package increases from the 228.8° position and switches to high-speed conveying speed at 274°. As a result, the cutting edge line that was close to the upper edge of the inner part moves toward the lower edge of the inner part. In addition, the gap between the upper blade edge and the lower blade edge on the edge line (the interval between the "lower blade edge shear start position curve" and the "upper blade edge position curve" in the graph) gradually widens from 228.8°. The cutting edges of the upper and lower blades never come into contact with the contents.

When the crank arm rotates at 293°, the bottom edge of the core and the cutting edge line (a straight line connecting the cutting edge of the upper blade and the cutting edge of the lower blade) match. It passes through the content part above the lower end position. However, at the 293° position, there is a 22mm gap between the cutting edge of the upper blade and the cutting edge of the lower blade, and after 293°, the gap between the cutting edges exceeds 22mm, so the contents of the pouch can pass through without interfering with the cutting edge. .

(10) It is possible to shorten the drop time of the pouch by cutting the pouch while the cutting edge is descending.
When the tip of a small bag to be cut is in contact with the chute surface with a chute angle of 45°, the small bag slides down at an initial speed of Vo = 0 (mm/sec) when cut by intermittent horizontal reciprocating motion. , When sachets with a pitch of 70 mm are continuously rotated and cut at 250 sachets/min, the sachets slide down at an initial speed of Vo = -189.8 mm/sec. In each case, the sliding distance on the upper surface of the chute is 100 mm, and when the sliding down time is calculated by changing the friction coefficient μ = 0 to 0.5 between the chute and the pouch, the horizontal axis is the friction coefficient, and the vertical axis is the sliding down time. Graphed (see FIG. 10).

Calculation formula for sliding down distance
S=Vo×t+g×(sin θ−μ×cos θ)×t ² /2

However, g is gravitational acceleration (9800mm/sec ² )

Calculating the above formula with Vo = -189.8mm/sec, θ = 45°, μ = 0 to 0.5, and S = 100mm, the slipping time of the pouch is as follows.
The values in ( ) are calculated when the initial speed is 0mm/sec.

μ = 0 t = 0.145sec (0.170sec)
μ = 0.1 t = 0.151sec (0.179sec)
μ = 0.2 t = 0.159sec (0.190sec)
μ = 0.3 t = 0.168sec (0.203sec)
μ = 0.4 t = 0.178sec (0.219sec)
μ = 0.5 t = 0.192 sec (0.240 sec)

When a continuous package with a pitch of 70 mm is cut and placed on a conveyor with an attachment at a fixed position, the attachment passes through the standard placement position every 0.24 seconds.

For example, even if the passage position of the attachment is set with the standard coefficient of friction μ=0.3, it is not possible in actual operation to exceed the coefficient of friction μ≧0.5 due to the drop in slipperiness due to dirt on the chute surface. sell. At this time, if the initial velocity Vo = 0, the time to slide down 100mm would exceed 0.24sec, and the injection would not be in time. The slip-down time is 0.192 sec, which satisfies the cycle time of 0.24 sec.

Even if there are time delay factors such as friction coefficient and catching, sliding down with initial speed creates a time margin that can be applied within the cycle time.

[3. effect]
The cutter unit of the embodiment has the following effects.
(1) Although the rotary cutter unit 50 is a guillotine cutting cutter, the vertical transport of the continuous package and the horizontal movement of the cutting edge can be continuously operated without stopping.

The upper blade unit 2 and the lower blade unit 3 are connected by a sliding joint (sliding guide unit 21) to form an extendable intermediate joint, and crank units 27 and 33 having equal crank arm radii are attached to both ends of this intermediate joint. In the rotary cutter unit 50 provided, when the respective crank arms 23 and 29 are reversely rotated at the same speed, the intermediate joint composed of the upper blade unit 2 and the lower blade unit 3 is always kept horizontal and moves vertically as a whole. The upper blade 10 at the tip of the upper blade unit 2 and the lower blade 18 at the tip of the lower blade unit 3 can repeatedly move back and forth against each other.

The rotary cutter unit 50 moves the cutting edge 11 of the upper blade and the cutting edge 19 of the lower blade while an intermediate joint composed of the upper blade unit 2 and the lower blade unit 3 connected by a sliding guide unit moves downward from above. From the open state, they advance in the horizontal direction to narrow the gap, and by advancing engagement (overlapping), the horizontal seal of the small bag is sandwiched and guillotine-type shear cutting proceeds. In addition, since the downward movement from the top of the intermediate joint is the same as the conveying direction of the continuous package 40, the conveying speed of the continuous package is synchronized with the descending speed of the intermediate joint, so that the continuous package can be conveyed. Shear cutting is possible without stopping. In addition, the continuous operation of the rotary motion of the crank arm that drives the rotary cutter unit 50 and the continuous driving of the transport of the continuous package eliminates the shock associated with the start and stop of the conventional intermittent drive of the cutter unit, and the change in acceleration is 1G. It has the effect of realizing the following smooth movement.

(2) By using the rotary cutter unit 50 to continuously operate the guillotine cutting and the transport of the continuous packages, high-speed cutting exceeding 250 pieces/minute was made possible.
With a conventional intermittent drive guillotine cutter, when high-speed cutting and loading of more than 250 pieces/minute is performed, the driving time for driving the continuous package and the reciprocating motion of the cutter is only 50% of the cycle time, resulting in continuous packaging. The transport speed of the body became high-speed transport exceeding 400mm/sec, and transport damage, variation in pitch measurement, and overrun of the stop position occurred due to the shock caused by the large acceleration that occurred when starting and stopping.

However, in the embodiment, by realizing the rotary cutter unit 50, the horizontal drive of the upper blade and the lower blade during the guillotine cut and the vertical drive of the continuous package can be continuously operated without stopping to cut the continuous package. By reducing the transport speed to 400 mm/sec or less and the acceleration to 1 G or less to eliminate transport impact, we were able to realize a high-speed cutting and loading machine that exceeds 250 pieces/minute, which was previously impossible.

In addition, the large acceleration that occurred during the start/stop of intermittent transport can be suppressed to 1G or less, and the transport speed has been reduced to less than half, reducing pinholes and cracks in the contents that occur due to transport fluttering and the shock of starting and stopping. It eliminates product quality deterioration due to chipping, stabilizes pitch detection, and eliminates overrun from the cutting position, which greatly eliminates cutting errors.

(3) Since the rotary cutter unit 50 employs a guillotine cutting method, the configuration is simple and the blade can be easily adjusted.
Conventionally, a rotary cutter was required to achieve a high-speed cutting input of more than 250 pieces/minute, but the rotary cutter requires precision and rigidity of the mechanism that supports the counter-rotating cutting blade and receiving blade. Therefore, not only is the structure complicated and expensive, but the contact adjustment between the cutting edge and the receiving edge affects the life and sharpness of the cutting edge. needed.

However, in the rotary guillotine cutter unit 50, since it is only necessary to align the blade back surfaces of the upper blade and the lower blade, the blades can be easily adjusted, the structure is simple, and the unit can be provided at a low price.

(4) Since the rotary cutter unit 50 cuts the sachet at an initial speed, the time delay during dropping through the chute is reduced.
In the embodiment, since the leading end pouch of the continuous package body is cut while having a descending speed, it can freely fall or slide down in the chute at a speed after cutting, and can be fed into the next process device. You can eliminate delays in delivery to

Conventionally, the continuous package was transported intermittently when cutting the sachets, so the sachets after cutting fell at an initial speed of "0 (mm/sec)". For this reason, if there are delay factors such as a decrease in the slipperiness of the chute (increase in the coefficient of friction) or catching, there are cases where the input to the next process cannot be done in time for the high-speed cutting input exceeding 250 pieces/minute, which is a bottleneck for speeding up. had become one.

In an embodiment, by using a rotary guillotine cutting mechanism, the continuous package is cut while descending at a speed that matches the descending speed of the cutting edge. Therefore, since the material falls at a certain initial speed, the time required to reach the next process is shortened, and even if there are delay factors such as a certain degree of deterioration in slipperiness and catching, the effect is that the material can be introduced within the cycle time.

Although the preferred embodiment has been described above, the pitch of the conveying pouches and the conveying speed are examples, and various modifications can be made within the scope of the present invention.
In the embodiment, the "rotational speed control unit" of the control motor changes the rotational speed of the drive shaft of the crank unit (rotational speed of the crank arm) to Nrpm corresponding to the cutting speed (N pieces/minute). However, the present invention is not limited to this, and the rotation speed control unit causes the upper blade and the lower blade to descend at a constant speed in synchronization with the second conveying speed in the overlapping section. (second modification).
In the rotation speed control unit of the embodiment, even if the drive shaft rotates at a constant speed, the cutting edge moves in a circular motion, so the vertical speed changes along a cosine curve (see FIG. 5). The example results in different control than the embodiment, but is within the scope of the present invention.
The uniform descending speed of the cutting edge in the second modification makes a part of the cosine curve constant, which complicates the control. , Since it is difficult to interfere with the sachet that has been cut off during the descent, it becomes easier to drop the sachet at the target position.

INDUSTRIAL APPLICABILITY The cutter unit of the present invention can be used in a small bag inserting device that cuts continuous packages.

1 cutter unit 2 upper blade unit 3 lower blade unit 4 upper blade shaft holder 5 connector 5a hole 6 upper blade rotation pin 7 compression coil spring 8 turning shaft 9 upper blade holder 10 upper blade 11 blade edge 12 connector base plate 13 upper blade guide mounting plate 14 Guide wheel 15 Lower blade shaft holder 16 Lower blade holder 18 Lower blade 18a Horn portion 19 Cutting edge 20 Lower blade guide bar 21 Sliding guide unit (intermediate member)
22 crankshaft (upper blade crankshaft)
22a stepped portion 23 crank arm (upper blade crank arm)
24 drive shaft (upper blade drive shaft)
25 bearing 26 upper blade driving pulley 27 upper blade crank unit 28 crankshaft (lower blade crankshaft)
29 crank arm (lower blade crank arm)
30 drive shaft (lower blade drive shaft)
32 Lower blade drive pulley 33 Lower blade crank unit 34 Front plate 36 Feed roller 40 Continuous package 50 Rotary cutter unit

Claims (5)

In a cutter unit that cuts a continuous package in which sachets are continuous,
An upper blade comprising an upper blade, an upper blade guide mounting plate attached to both sides of the cutting edge of the upper blade, and a guide ring disposed vertically facing the upper blade guide mounting plate with a gap between the outer diameters thereof. a unit;
a lower blade unit comprising a U-shaped lower blade with horns on both ends and lower blade guide bars attached to both ends;
A guide wheel of the upper blade unit and a lower blade guide bar of the lower blade unit are combined and connected to an intermediate portion between the upper blade unit and the lower blade unit by a sliding joint that is movably connected back and forth, and the upper blade is and a sliding guide unit that supports the blade edge of the lower blade so that the interval can be changed;
a drive unit comprising an upper blade crank unit and a lower blade crank unit for moving the upper blade unit and the lower blade unit;
A cutter unit comprising: In a cutter unit that cuts a continuous package in which sachets are continuous,
An upper blade unit comprising an upper blade, an upper blade guide mounting plate attached to both sides of the cutting edge of the upper blade, and a guide ring incorporated into the upper blade guide mounting plate with a gap provided between the outer diameters of the upper blade guide mounting plate so as to vertically face each other. and,
Equipped with a U-shaped lower blade with horns on both ends, and lower blade guide bars fixed to both outer end faces of the horns of the lower blade extending from both ends of the lower blade toward the upper blade unit. a lower blade unit;
By inserting the lower blade guide bar of the lower blade unit into the gap provided between the outer diameters of the guide wheels of the upper blade unit, the upper blade unit and the lower blade unit are connected so as to be movable back and forth at an intermediate portion. a sliding guide unit that is connected by a sliding joint and supports the blade edges of the upper blade and the lower blade so that the interval between them can be changed;
a drive unit comprising an upper blade crank unit and a lower blade crank unit for moving the upper blade unit and the lower blade unit;
A cutter unit comprising: In a cutter unit that cuts a continuous package in which sachets are continuous,
An upper blade, an upper blade guide mounting plate attached to both sides of the cutting edge of the upper blade, and a plurality of guide rings arranged on the upper blade guide mounting plate so as to vertically face the upper and lower surfaces of the lower blade guide bar. and an upper blade unit that can adjust the gap between the outer diameters of the guide wheels to the thickness of the lower blade guide bar,
Equipped with a U-shaped lower blade with horns on both ends, and lower blade guide bars fixed to both outer end faces of the horns of the lower blade extending from both ends of the lower blade toward the upper blade unit. a lower blade unit;
The outer circumference of the guide wheel of the upper blade unit is in close contact with the upper and lower surfaces of the lower blade guide bar of the lower blade guide unit so that the upper blade unit and the lower blade unit can roll horizontally. a sliding guide unit that is combined with and connected by a sliding pair that is connected so as to move back and forth so that the interval between the cutting edges of the upper blade and the lower blade can be changed;
a drive unit comprising an upper blade crank unit and a lower blade crank unit for moving the upper blade unit and the lower blade unit;
A cutter unit comprising: 2. The engagement between the cutting edge of said upper blade and said lower blade is such that the cutting edge of said upper blade which is oscillatingly rotated by a spring is pressed against the rear surface of said fixedly mounted lower blade with a predetermined pressure. 4. The cutter unit according to any one of items 1 to 3. The upper blade crank unit and the lower blade crank unit in the drive unit each have a drive shaft to which rotational force is input from a drive source, and a crank arm that rotates around the drive shaft,
In the upper blade crank unit, an end of a crank arm having a rotation radius from the center of the drive shaft is rotatably connected to the upper blade unit,
In the lower blade crank unit, the end of the crank arm spaced apart from the center of the drive shaft by a radius of rotation is rotatably connected to the lower blade unit,
4. A cutter unit according to claim 1, characterized in that each crank arm rotates continuously at equal speeds and in opposite directions.

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