JP7510658B2 - Packaging Machine - Google Patents

Description

The present invention relates to a packaging machine that performs packaging by wrapping bands around items to be packaged in a fully or semi-automatic manner.

Figure 14 shows an example of the configuration of a conventional packaging machine that performs semi-automatic packaging by wrapping bands around the items to be packaged.

The packaging machine 100 shown in FIG. 14 is equipped with a table 107 on which the packaged item W is placed, a band reel (not shown) on which a band B such as a PP band used for packaging is wound, a roller unit 120 that pulls out the band B from the band reel and sends it out onto the table 107, as well as pulling back and tightening the sent-out band B, and a sealing unit 140 that is positioned below the table 107 and grips, welds and cuts the band B.

The roller unit 120 includes a feed motor (not shown), a feed roller 121 that is rotated by the feed motor in a rotation direction that feeds the band B onto the table 107 (referred to as the "feed rotation direction" in this specification) and a rotation direction that pulls back and tightens the fed band B (referred to as the "tightening rotation direction" in this specification), a touch roller 123 that presses the band B against the outer periphery of the feed roller 121, and a means for moving the touch roller 123 between a contact position with the feed roller 121 and a spaced position spaced from the feed roller 121, such as a solenoid (not shown).

The sealing unit 140 also includes a cam motor 141, a camshaft 142 that is rotated by the cam motor 141, cams 143a to 143c that rotate together with the camshaft 142, and a right presser 144, a left presser 145, and a center presser 146 that are raised and lowered by the cams 143a to 143c.

The packaging machine 100 is further provided with a first limit switch 152 (see FIG. 14A) that detects when the tip of the band B is inserted into a predetermined position in the sealing unit 140, a second limit switch (not shown) that detects the rotational position of the camshaft 142, and a controller (not shown) consisting of an electronic control device that controls the operation of the feed motor and solenoid (neither shown) in the roller unit 120 and the cam motor 141 in the sealing unit 140 based on the detection signals from the first and second limit switches and the tightening force of the band B.

In the packaging machine 100 shown in FIG. 14 and configured as described above, when the second limit switch detects that the rotational position of the camshaft 142 has returned to the original position where the right pressure member 144, the left pressure member 145, and the center pressure member 146 are all in the lowered position, the controller turns on the solenoid to bring the touch roller 123 into contact with the feed roller 121 and rotates the feed motor (feed roller 121) in the supply rotation direction (counterclockwise in the illustrated example) to feed the band B pulled out from the band reel onto the table 107, thereby feeding the band [see FIG. 14 (F)], and when a predetermined length of band B has been fed, the rotation of the feed motor is stopped and the touch roller 123 is separated from the feed roller 121 to enter a standby state.

In this standby state, when the user places the item W to be packed on the table 107 and inserts the tip of the band B sent out onto the table 107 into a predetermined position in the sealing unit 140 located below the table 107 (see FIG. 14(A)), the first limit switch 152 detects the insertion of the tip of the band B and outputs a detection signal. The controller that receives this detection signal rotates the cam motor 141 of the sealing unit 140 and rotates the camshaft 142 until the right presser 144 rises to a position where it grips the band B (see FIG. 14(B)).

When the second limit switch detects that the camshaft 142 has rotated to the raised position of the right presser 144, the controller stops the rotation of the cam motor 141, and at the same time turns on the solenoid of the roller unit 120 to bring the touch roller 123 into contact with the outer periphery of the feed roller 121, and rotates the feed motor (feed roller 121) in the tightening rotation direction (clockwise in the illustrated example) to start tightening the band B (see Figure 14 (C)).

When the band B is tightened to the preset tightening force, the controller restarts the rotation of the cam motor 141 of the sealing unit 140, causing the left presser 145 of the sealing unit 140 to rise and grip the supply side end of the band B, holding the band B wrapped and tightened around the outer periphery of the packaged item W. The controller then stops the rotation of the feed motor (feed roller 121), turns off the solenoid, and separates the touch roller 123 from the feed roller 121, completing the tightening process (Figure 14 (D)).

After that, when the camshaft 142 is further rotated by the cam motor 141, the middle presser 146 provided on the sealing unit 140 rises, the band B is welded and cut, and the packaging of the packaged item W is completed [Fig. 14 (E)]. As the camshaft 142 continues to rotate, the right presser 144, left presser 145, and middle presser 146 all descend, and the camshaft 142 rotates to its original position.

When the second limit switch detects that the camshaft 142 has returned to its original position, the controller stops the rotation of the cam motor 141, turns on the solenoid, and rotates the feed motor (feed roller 121) in the supply rotation direction while the touch roller 123 is in contact with the feed roller 121, feeding the band B onto the table 107 (see Figure 14 (F)). When a predetermined length of band B has been fed, the controller stops the feed motor and turns off the solenoid to separate the touch roller 123 from the feed roller 121, and in this state goes into standby mode until the first limit switch 152 detects the insertion of the tip of band B (operation from Figure 14 (A) onwards).

In the series of operations of the packaging machine 100 described above, the user inserts the tip of band B into a specified position in the sealing unit 140 located below the table 107, and once the first limit switch 152 detects this insertion of the tip of band B and packaging begins [Figure 14 (A)], the packaging machine 100 is configured to automatically perform the series of operations continuously without stopping or interruption until the band feeding operation for the next packaging process [Figure 14 (F)] is completed.

Therefore, once the packing process has begun, even if the strapping position on the packaged item W or the placement of the backing plate is misaligned, the packing process will continue in that misaligned state, and the user will not be able to correct this midway.

In consideration of these problems, Patent Document 1, which will be described later, proposes a packaging machine 100 that, in addition to automatically starting to tighten and weld the band B as described above, when the "manual" mode is selected using the operation mode changeover switch, allows the user to manually input commands to start, stop, and restart tightening, as well as to end tightening and start welding, by operating a switch.

In the packaging machine described in Patent Document 1, the operation when the "manual" mode is selected will be described with reference to FIG. 15. When the first limit switch 152 detects that the end of band B has been inserted into a predetermined position in the sealing unit 140 [FIG. 15(A)], the controller rotates the cam motor 141 to raise the right presser to grip band B, and then the operation up to the point where the cam motor is stopped by a detection signal from the second limit switch is the same as that of the conventional packaging machine described with reference to FIG. 14. However, in the conventional packaging machine described with reference to FIG. 14, the detection signal from the second limit switch Upon receiving the output signal, the controller automatically rotates the feed motor (feed roller 121) in the tightening direction and turns on the solenoid to bring the touch roller 123 into contact with the feed roller 121 to begin tightening the band B. However, in the "manual" mode of the packaging machine described in Patent Document 1, the controller does not operate the feed motor or solenoid even when the right presser 144 has risen and finished gripping the band B, and therefore is configured to stop operation and enter a standby state without starting to pull back or tighten the band (see Figure 15 (B)).

In this standby state, when the user turns on the manual tightening switch (not shown), the controller turns on the solenoid to bring the touch roller 123 into contact with the outer periphery of the feed roller 121, and rotates the feed motor in the tightening direction to begin tightening the band B (see Figure 15 (C)).

The controller tightens band B until the user turns off the manual tightening switch, regardless of whether the tightening force of band B has reached the set value. When the manual tightening switch is turned off, the controller stops the feed motor and turns off the solenoid to separate the touch roller 123 from the feed roller 121 and stop tightening, and waits in this state until the user inputs a command to resume tightening or to end tightening (see Figure 15 (D)). During this waiting time, the band winding position and the arrangement of the backing plate can be adjusted.

The controller remains in this standby state until the user operates the tightening end switch (not shown) to input a tightening end command. When the user turns the manual tightening switch ON again, the controller returns to FIG. 15(C), turns the solenoid ON, and rotates the feed motor in the tightening direction to resume tightening. When the manual tightening switch is turned OFF, the controller stops the feed motor and turns the solenoid OFF to stop tightening and enter the standby state of FIG. 15(D).

In this way, when the tightening is stopped in the standby state (Fig. 15 (D)), and the user further operates the tightening end switch (not shown) to input a tightening end command for band B, the controller restarts the rotation of the cam motor 141 of the sealing unit 140, which causes the left presser 145 provided on the sealing unit 140 to rise and grip band B (Fig. 15 (E)), after which the middle presser 146 rises to weld and cut band B (Fig. 15 (F)), and then the right presser 144, left presser 145, and middle presser 146 all fall due to the rotation of the cam shaft 142, and the cam shaft 142 When it returns to its original position, the controller turns on the solenoid based on the detection signal of the second limit switch that detects this return to the original position, bringing the touch roller 123 into contact with the feed roller 121, and rotates the feed motor (feed roller 121) in the supply rotation direction to feed out a specified length of band B (Figure 15 (G)). After that, the feed motor is stopped, the solenoid is turned off, and the touch roller 123 is separated from the feed roller 121 and waits. When the first limit switch 152 detects the insertion of the band end, the next process of packaging from Figure 15 (A) onwards begins.

JP 2003-170906 A

In the packaging machine described in the above-mentioned Patent Document 1, when the manual mode is selected, the band B is tightened only while the manual tightening switch is ON. Also, even after tightening has started, tightening can be stopped by turning the manual tightening switch OFF [see FIG. 15 (D)]. While tightening is stopped in this way, the user can adjust the band attachment position relative to the packaged item or the placement of the backing plate.

However, in the packaging machine described in Patent Document 1, when the "manual" mode is selected, the stop of tightening the band and the start of subsequent welding of the band are not automatically linked, but are instead commanded by the user by separately operating two switches (manual tightening switch and tightening end switch) that are provided separately. Therefore, even if the band is tightened in the tightening process, it will slacken before welding of the band starts.

In other words, in the known packaging machine described with reference to Figure 14, after the left presser 145 of the sealing unit 140 rises to grip the band B, the feed motor (feed roller 121) is stopped and the touch roller 123 is separated [Figure 14 (D)], so that the band B can be held in a tight state without loosening until welding is performed.

However, in the packaging machine described in Patent Document 1, the feed motor and solenoid are controlled to be turned on and off in conjunction with the user turning on and off the manual tightening switch. When the manual tightening switch is turned off, the feed motor (feed roller 121) stops and the touch roller 123 moves away (Fig. 15 (D)). By operating the tightening end switch, a tightening end command is input, and the tension on band B is released before the band is gripped by the left clamp of the sealing unit 140 (Fig. 15 (E)).

Releasing the tension on band B in this way is convenient for adjusting the band attachment position and the placement of the backing plate, but it means that band B is welded in a loose state.

Even if the packaging machine described in Patent Document 1 is modified so that the touch roller 123 separates after the left pressure member 145 of the sealing unit 140 rises, the band B is gripped by the left pressure member 145 of the sealing unit 140 after the feed motor (feed roller 121) is stopped by turning off the manual tightening switch.

Therefore, when the power supply to the feed motor is stopped and the rotational torque of the feed roller 121 disappears, the tension of band B causes the feed roller 121 to rotate in the supply rotation direction, which may cause slack in band B.

When the feed motor is connected to the feed roller 121 via a reducer, even if the power supply to the feed motor is stopped, a certain degree of rotational resistance is applied to the feed roller 121. Therefore, even after the feed motor is stopped, if the left presser 145 is configured to be raised before the touch roller 123 is released, it is possible to prevent slackening of the band B to a certain extent.

However, in recent years, this type of packaging machine has come to be used not only for packaging items with a fixed shape, such as products packed in cardboard boxes, but also for packaging items that are deformable and compressible, such as clothing (used clothing), rags, hand towels, waste paper, and rush-like sheets.

When banding items that have a fixed shape, such as the cardboard boxes mentioned above, it is common to tighten the items with a force that does not deform them. However, when packing items that are deformable or compressible, as mentioned above, there is a demand to tighten band B with a strong force, actively deform and compress the items, and pack them in the smallest possible size, in order to reduce storage space during transportation and storage.

As a result, in this type of application, the band B is tightened with a strong tightening force. If the feed motor is stopped before the left presser 145 of the sealing unit 140 rises to grip the band B, the feed roller 121 will rotate in the supply rotation direction, even if there is rotational resistance in the feed roller 121 due to the intervention of a reducer or the like, and the band B that has just been tightened will become loose.

To prevent such slack in band B, the packaging machine in cited document 1 must not only be modified to a configuration in which the touch roller 123 is separated after the left pressure member 145 of the sealing unit 140 rises, but must also be modified to a configuration that includes a brake means, such as an electromagnetic brake, that restricts the rotation of the feed motor (feed roller 121) when power is cut off.

However, in a configuration where an electromagnetic brake is provided, it is necessary to secure space for the electromagnetic brake within the packaging machine 100, which requires significant design changes. In addition, electromagnetic brakes are expensive, and installing an electromagnetic brake increases the price of the packaging machine.

In addition, in the packaging machine described in Patent Document 1, the band contacts the feed roller 121 with a single touch roller 123, so the contact resistance of the band B with the feed roller 121 is low. When tightening with a high tightening force, such as when packing a packaged item that is deformable and compressible as described above, the band may slip on the feed roller 121 and become loose, even if the rotation of the feed roller is restricted by an electromagnetic brake or the like.

The present invention has been made to eliminate the drawbacks of the above-mentioned conventional technology, and aims to provide a packaging machine with a relatively simple configuration that can hold a tightened band in a tight state without loosening until the sealing unit 140 completes the gripping or welding of the band, and therefore can be used suitably for compressing and packaging deformable and compressible items such as the above-mentioned clothing (used clothing), rags (tattered cloth), hand towels, waste paper, and rush-style sheets.

Below, the means for solving the problem are described together with the reference symbols used in the description of the embodiment of the invention. These reference symbols are intended to clarify the correspondence between the description of the claims and the description of the embodiment of the invention, and needless to say, are not used in a restrictive manner in interpreting the technical scope of the present invention.

In order to achieve the above object, the packaging machine 1 of the present invention comprises:
A packaging machine 1 includes a band reel 8, a roller unit 20 that pulls out and delivers a band B from the band reel 8 and tightens the delivered band B, and a sealing unit 40 that grips the band B and welds and cuts the band.
The roller unit 20 is
A feed motor 31,
a feed roller 21 that is selectively rotated by the feed motor 31 in a supply rotation direction in which the band B is fed out and in a tightening rotation direction in which the band B is tightened;
a constant contact roller 22 that is constantly in contact with the outer periphery of the feed roller 21 via the band B ;
a tightening touch roller 23 that comes into contact with the outer periphery of the feed roller 21 via the band B only when the band B is tightened;
a swing arm 26 to which the tightening touch roller 23 is rotatably attached and which swings between a contact position where the tightening touch roller 23 contacts the outer periphery of the feed roller 21 and a separation position where the tightening touch roller 23 is separated from the outer periphery of the feed roller 21;
a swing arm driving means 33 for swinging the swing arm 26 to the contact position when tightening the band B , and swinging the swing arm 26 to the separated position after the band B is gripped by a loosening prevention presser (left presser) 45 of the sealing unit 40 so that the tightened band B does not loosen;
a ratchet gear 27 attached to the feed roller 21 and rotating together with the feed roller 21;
a locking claw 28 that is pivotally supported between an engagement position where it engages with the ratchet gear 27 and a release position where it is released from engagement with the ratchet gear 27, and that engages with the ratchet gear 27 at the engagement position, allowing the ratchet gear 27 to rotate in the tightening rotation direction, but restricting rotation in the supply rotation direction;
The locking claw 28 is connected to the oscillating arm 26 so that when the oscillating arm 26 is in the contact position, the locking claw 28 is swung to the engaged position, and when the oscillating arm 26 is in the separated position, the locking claw 28 is swung to the released position (Claim 1: see Figures 3 to 5).

A controller 60 can be provided that causes the feed motor 31 to perform a disengagement rotation in the tightening rotation direction for a very short time (for example, 100 msec or more, preferably 150 msec or more, so as not to reduce work efficiency) at the same time as the swing arm drive means 33 performs the operation of swinging the swing arm 26 to the separated position, or slightly delayed from the operation (for example, 30 msec or more, preferably 50 msec or more, so as not to reduce work efficiency) (Claim 2).

The connection between the locking claw 28 and the swinging arm 26 is preferably made via a spring such as a leaf spring or coil spring as a biasing means (in this embodiment, a leaf spring 29) that biases the locking claw 28 toward the ratchet gear 27 (Claim 3).

The sealing unit 40 is
A cam motor 41,
A camshaft 42 rotated by the cam motor 41;
Cams 43a to 43c that rotate together with the camshaft 42;
The band end presser (right presser) 44 operates with the rotation of the cams 43a to 43c and holds the tip of the band B from before tightening begins until welding is completed, the loosening prevention presser (left presser) 45 holds the band B in a tight state until welding is completed after tightening the band B, and the welding presser (middle presser) 46 melts and presses the band B and cuts it.
a rotational position detection means (second limit switch) 53 for detecting a second detection position, which is a rotational position of the camshaft 42 at which the loosening prevention presser (left presser) of the sealing unit 40 starts gripping the band;
The controller 60 may be configured to operate the swing arm drive means 33 to swing the swing arm 26 to the separated position upon detection of the second detection position by the rotational position detection means (second limit switch) 53, and to cause the feed motor 31 to perform the disengagement rotation after a predetermined time has elapsed from the detection of the second detection position (for example, 30 msec or more, preferably 50 msec or more, a short time that does not reduce work efficiency) (Claim 4).

Furthermore, in the packaging machine 1 of the present invention,
A band insertion detection means (first limit switch) 52 is provided to detect the insertion of the band end into a predetermined position of the sealing unit 40,
The rotational position detection means (second limit switch) 53 is capable of detecting an original position, which is a rotational position of the camshaft 42 when the band end holder (right holder) 44, the loosening prevention holder (left holder) 45, and the welding holder (middle holder) 46 of the sealing unit 40 are all in an inoperative state, and a first detection position, which is a rotational position of the camshaft 42 where the band end holder (right holder) 44 starts gripping the band B,
The controller 60
A band end gripping process (FIG. 8B) in which the cam motor 41 starts rotating upon receiving a detection signal from the band insertion detection means (first limit switch) 52, and the band end is gripped by the band end holder (right holder) 44.
A band pull -back process (FIG. 8C) in which the cam motor 41 is stopped when the rotation position detection means (second limit switch) 53 detects the first detection position and the feed motor is rotated in the tightening rotation direction to pull back the band .
After the band B is pulled back by the band pulling back process, the swing arm driving means 33 is operated to swing the swing arm 26 to the contact position to further tighten the band B, that is, a band tightening process (FIG. 8(D)).
When the tightening force of the band B reaches a predetermined tightening force, the feed motor 31 is stopped and the rotation of the cam motor 41 is resumed to grip the band B with the slack prevention presser (left presser) 45 to prevent slack in the band, and the swing arm drive means 33 is operated to swing the swing arm 26 to the separated position upon detection of the second detection position by the rotation position detection means (second limit switch) 53 (FIG. 8(E)).
A disengagement process (FIG. 8(F)) in which the feed motor 31 is caused to perform the disengagement rotation after a predetermined time (for example, 30 msec or more, preferably 50 msec or more, which is a short time that does not reduce work efficiency) has elapsed since the detection of the second detection position by the rotation position detection means (second limit switch) 53.
The rotation of the cam motor 41 is continued, and the band is welded and cut by the welding presser (middle presser), cutting and welding process (FIG. 8(G)).
When the rotational position detection means (second limit switch) 53 detects the original position, the rotation of the cam motor 41 is stopped and the feed motor 31 is rotated in the supply rotation direction to feed the band B, in a band feed process (FIG. 8(H)).
After a predetermined length of the band B is fed, the rotation of the feed motor 31 is stopped and the process waits until a detection signal is received from the band insertion detection means (first limit switch) 52 (FIG. 8A).
The device may be configured to execute automatic packing control (claim 5 ).

In addition, the packaging machine 1 of the present invention is further provided with a manual tightening switch 54 and a welding start switch 55 that are operated by a user,
The controller 60, instead of the automatic packing control,
Upon receiving a detection signal from the band insertion detection means (first limit switch) 52, the cam motor 41 starts rotating and the band end is gripped by the band end holder (right holder) 44 (FIG. 10B).
A band pulling back process (FIG. 10C) in which the cam motor 41 is stopped when the rotation position detection means (second limit switch) 53 detects the first detection position, and the feed motor 31 is rotated in the tightening rotation direction to pull back the band .
After the band B is pulled back by the band pull-back process, the feed motor 31 is stopped to end the pull-back, and the swing arm driving means 33 is operated to swing the swing arm to the contact position, thereby entering a tightening start standby state (FIG. 10(D)).
The manual tightening switch 54 is turned on to rotate the feed motor 31 in the tightening rotation direction, and the manual tightening switch 54 is turned off to stop the rotation of the feed motor 31 and return to the tightening start standby state, in a band tightening and standby process (FIGS. 10(E) and (F)).
When a welding start command is received from the welding start switch 55 in the tightening start standby state, the rotation of the cam motor 41 is resumed to grip the band B with the slack prevention presser (left presser) 45 to prevent slack in the band, and when the second detection position is detected by the rotation position detection means (second limit switch) 53, the swing arm drive means 33 is operated to swing the swing arm 26 to the separated position, a slack prevention process (FIG. 10(G)).
A disengagement process (FIG. 10(H)) in which the feed motor 31 is caused to perform the disengagement rotation after a predetermined time (for example, 30 msec or more, preferably 50 msec or more, which is a short time that does not reduce work efficiency) has elapsed since the detection of the second detection position by the rotation position detection means (second limit switch) 53.
The rotation of the cam motor 41 is continued, and the welding presser (middle presser) 46 welds and cuts the band B. Cutting and welding process (FIG. 10(I)).
When the rotational position detection means (second limit switch) 53 detects the original position, the rotation of the cam motor 41 is stopped and the feed motor 31 is rotated in the supply rotation direction to feed the band B, in a band feed process (FIG. 10(J)).
After a predetermined length of band B has been fed, the feed motor 31 is stopped from rotating and the process waits until a detection signal is received from the band insertion detection means (first limit switch) 52 (FIG. 10A).
The present invention may be configured to execute semi-automatic packing control (claim 6).

Furthermore, the controller 60, instead of the semi-automatic packing control,
Upon receiving a detection signal from the band insertion detection means (first limit switch) 52, the cam motor 41 starts rotating to grip the band end with the band end holder (right holder) 44, and the cam motor 41 is stopped upon detection of the first detection position by the rotation position detection means (second limit switch) 53. In addition, the swing arm drive means 33 is operated to swing the swing arm 26 to the contact position, thereby entering a tightening start standby state; this is a band end gripping and tightening start standby process (FIG. 12(B)).
The manual tightening switch 54 is turned on to rotate the feed motor 31 in the tightening rotation direction, and the manual tightening switch 54 is turned off to stop the rotation of the feed motor 31 and return to the tightening start standby state, in a band tightening and standby process (FIGS. 12(C) and (D)).
When a welding start command is received from the welding start switch 55 in the tightening start standby state, the rotation of the cam motor 41 is resumed to grip the band B with the slack prevention presser (left presser) 45 to prevent slack in the band, and when the second detection position is detected by the rotation position detection means (second limit switch) 53, the swing arm drive means 33 is operated to swing the swing arm 26 to the separated position, a slack prevention process (FIG. 12(E)).
A disengagement process (FIG. 12(F)) in which the feed motor 31 is caused to perform the disengagement rotation after a predetermined time (for example, 30 msec or more, preferably 50 msec or more, which is a short time that does not reduce work efficiency) has elapsed since the detection of the second detection position by the rotation position detection means (second limit switch) 53.
The rotation of the cam motor 41 is continued, and the welding presser (middle presser) 46 welds and cuts the band B. Cutting and welding process (FIG. 12(G)).
When the rotational position detection means (second limit switch) 53 detects the original position, the rotation of the cam motor 41 is stopped and the feed motor 31 is rotated in the supply rotation direction to feed the band B, in a band feed process (FIG. 12(H)).
After a predetermined length of the band B is fed, the rotation of the feed motor 31 is stopped, and in this state, the process waits until a detection signal is received from the band insertion detection means (first limit switch) 52 (FIG. 12A).
The present invention may be configured to execute manual packing control (claim 7).

Furthermore, the packaging machine 1 of the present invention is further provided with an operation mode changeover switch 51 operated by a user,
The controller 60 may be configured to execute any one of the automatic packing control, semi-automatic packing control, or manual packing control in accordance with the user's selection made by operating the operation mode changeover switch 51 (claims 8 , 9, and 10 ).

Thanks to the configuration of the present invention described above, the packaging machine 1 of the present invention can achieve the following remarkable effects:

The feed roller 21 is fitted with a ratchet gear 27 that rotates together with the feed roller 21, and a locking claw 28 is provided that engages with the ratchet gear 27 to restrict rotation of the ratchet gear 27 in the supply rotation direction. This restricts the rotation of the feed roller 21 in the supply rotation direction even after the feed motor 31 stops rotating after the feed roller 21 tightens the band B, preventing slack in the band B from occurring during the time until the anti-slack presser (left presser) 45 of the sealing unit 40 rises and grips the band B.

As described with reference to Figures 14 and 15, in a configuration in which band B is brought into contact with the feed roller 121 by a single touch roller 123, the touch roller 123 is brought into contact with the feed roller 121 not only when band B is tightened, but also when band B is fed.

Therefore, if a ratchet gear and a locking claw are provided in this packaging machine 100, and if the operation of the locking claw 28 is also controlled by the solenoid that moves the touch roller 123 toward and away from the feed roller 121, the locking claw 28 will be engaged with the ratchet gear 27 even when the band B is being fed, and the band B will not be able to be fed out.

In contrast, in the configuration of the packaging machine 1 of the present invention, a constant contact roller 22 that is in constant contact with the feed roller 21 is provided as a touch roller that contacts the feed roller 21, and the band B is fed out by the contact between this constant contact roller 22 and the feed roller 21. At the same time, a tightening touch roller 23 that can be moved toward and away from the feed roller 21 is separately provided, and this tightening touch roller 23 is brought into contact with the feed roller 21 only when tightening the band B. This allows the operation of the locking claw 28 to be controlled simultaneously by the driving means (solenoid 33) of the swing arm 26 that moves the tightening touch roller 23 between the contact position and the separated position.

In this way, by sharing parts with other members, it was possible to easily add a ratchet mechanism at low cost that restricts the rotation of the feed roller 21 in the supply rotation direction only when the band B is tightened, while minimizing the increase in the number of parts, and that easily releases the restriction when the band B is fed out, with a relatively simple configuration.

In addition, by using the constant contact touch roller 22 and the tightening touch roller 23 to bring band B into contact with the outer periphery of the feed roller 21, even when tightening with high torque, band B is less likely to slip on the outer periphery of the feed roller 21 because of the two touch rollers, the constant contact touch roller 22 and the tightening touch roller 23. This makes it suitable for use in applications where deformable and compressible packed items such as the aforementioned clothing and rags are tightened with high tightening force until the packaged item becomes as small as possible.

Furthermore, by restricting the rotation of the feed roller 21 in the supply rotation direction through the engagement of the ratchet gear 27 and the locking pawl 28 described above, when the tip 28a of the locking pawl 28 passes over the tooth tip of the ratchet gear 27 during tightening of the band B, a clicking sound is generated. This clicking sound allows the user to audibly confirm that the band B is being tightened, and as the band B is tightened, the intervals between clicks become longer, and this change in sound allows the user to audibly confirm the tightening state.

When the feed motor 31 is stopped and the tension of the band B causes the feed roller 21 to rotate in the supply rotation direction, the tip 28a of the locking claw 28 is firmly wedged between the teeth of the ratchet gear 27. In particular, when the left presser 45 of the sealing unit 40 rises to grip the band B, the tension of the band B increases further, causing the tip 28a of the locking claw 28 to be firmly wedged between the teeth of the ratchet gear 27. Even if the solenoid 33, which is the swing arm drive means, is turned OFF, it becomes difficult to remove the tip 28a of the locking claw 28 from between the teeth of the ratchet gear 27.

In contrast, in a configuration in which the feed motor 31 is rotated in the tightening rotation direction for a very short time at the same time as or slightly after the operation of the swing arm drive means 33 to swing the swing arm 26 to the separated position, the disengagement rotation rotates the feed motor 31 in the tightening rotation direction. Even if the tightening of the band B is completed and the left retainer 45 of the sealing unit 40 rises, increasing the tension of the band B and causing the tip 28a of the locking claw 28 to bite between the teeth of the ratchet gear 27, the disengagement rotation rotates the ratchet gear 27 slightly in the tightening rotation direction, and the tip 28a of the locking claw 28 tries to get over the tip of the ratchet gear 27's tooth and falls out of the gap, making it easy to remove the tip of the locking claw from the gap.

In addition, in a configuration in which the locking claw 28 and the swinging arm 26 are connected via a spring such as a leaf spring 29 or a coil spring as a biasing means (leaf spring 29 in the embodiment), even if the tip 28a of the locking claw 28 is stuck in the ratchet gear 27 and cannot be removed, the swinging arm drive means 33 can swing the swinging arm 26 against the biasing force of the leaf spring 29, thereby separating the tightening touch roller 23 from the feed roller 21 and releasing the tension of the band.

In this way, the tension of the band that rotates the feed roller 21, and therefore the ratchet gear 27, in a direction that causes the tip 28a of the locking claw 28 to bite into the teeth of the ratchet gear 27 is released, making it even easier to disengage the locking claw 28 from the ratchet gear 27.

Furthermore, by detecting the second detection position by the rotational position detection means (second limit switch) 53, after a predetermined time has elapsed (for example, 30 msec or more, preferably 50 msec or more, a short time that does not reduce work efficiency), the feed motor 31 is caused to perform the disengagement rotation, so that the tightening touch roller 23 is separated from the feed roller 21, and the disengagement rotation can be performed reliably in a state where the load on the feed roller 21 is reliably removed.

The packaging machine of the present invention equipped with the roller unit 20 described above can be applied to any packaging machine that performs the automatic packaging control, semi-automatic packaging control, or manual packaging control described above, and in a configuration in which an operation mode changeover switch 51 is provided to enable switching between each control, the user can select the appropriate packaging method according to the application.

1 is a perspective view of a packaging machine to which the present invention is applied; FIG. 2 is a perspective view of another packaging machine to which the present invention is applied. FIG. FIG. FIG. 4 is a rear view of the roller unit with the feed motor removed. FIG. 2 is a schematic diagram illustrating a control system in the packaging machine of the present invention. Controller operation flow (operation mode selection) FIG. 4 is an explanatory diagram showing the operation of each part of the packaging machine in chronological order during automatic packaging. 4 is an operation flow diagram of the controller during automatic packing control. FIG. 4 is an explanatory diagram showing the operation of each part of the packaging machine in chronological order during semi-automatic packaging. 4 is an operation flow diagram of the controller during semi-automatic packaging control. FIG. 4 is an explanatory diagram showing the operation of each part of the packing machine in chronological order during manual packing. 4 is an operation flow diagram of the controller during manual packing. FIG. 1 is an explanatory diagram showing the operation of each part of a semi-automatic packaging machine (conventional) in chronological order. FIG. 2 is an explanatory diagram showing the operation of each part of the packaging machine in a manual mode in the packaging machine of Patent Document 1 in chronological order.

The packaging machine 1 of the present invention will be described below with reference to the attached drawings.

In the following explanation, an example of the configuration of the packaging machine 1 of the present invention is described as a semi-automatic packaging machine (a type of packaging machine in which the user places the band B on the outer periphery of the packaged item W and inserts the tip of the band B into a predetermined position in the sealing unit 40). However, the configuration of the packaging machine 1 of the present invention is not limited to the illustrated embodiment, and it can also be applied to a known fully automatic packaging machine equipped with a band guide arch on the table 7 (a type of packaging machine in which the user automatically places the band B on the outer periphery of the packaged item W and inserts the tip of the band B into a predetermined position in the sealing unit 40).

[Overall structure of packaging machine]
In FIG. 1, reference numeral 1 denotes a packaging machine of the present invention. This packaging machine 1 comprises a table 7 on which an item W to be packaged is placed, a band reel 8 on which a band B such as a PP band used for packaging is wound, a roller unit 20 which pulls out a predetermined length of band B from the band reel 8 and sends it out onto the table 7, as well as pulling back and tightening the sent-out band B, and a sealing unit 40 which is disposed below the table 7, grips the band B, and cuts and welds it.

In the embodiment shown in FIG. 1, the packaging machine 1 of the present invention has been described as having the table 7 described above as an example, but the configuration of the present invention is not limited to the packaging machine 1 shown in FIG. 1, and can also be applied to packaging machines that do not have the table 7 described above, such as a packaging machine 1' for pallet packaging that has a band guide 7' that is inserted into the fork insertion opening of the pallet as shown in FIG. 2, or a packaging machine (not shown) used to wrap a band horizontally around the item W to be packaged.

[Roller unit]
In the packaging machine 1 shown in FIG. 1, the aforementioned roller unit 20, which supplies the band B onto the table 7, pulls back the supplied band B, and tightens the band B around the outer periphery of the packaged item W, includes a feed roller 21, a constant contact roller 22 that is constantly in contact with the outer periphery of the feed roller 21, and a tightening touch roller 23 that contacts the outer periphery of the feed roller 21 when tightening the band B, as shown in FIG. 3, and in the illustrated embodiment, each of these rollers 21 to 23 is attached to a bracket plate 24 that is attached vertically to the bottom side of the table 7.

The rotation shaft of the feed roller 21 passes through the bracket plate 24 mentioned above and is connected to the feed motor 31 on the rear side of the paper in FIG. 3 (see FIG. 4). This feed motor 31 is configured to rotate in the supply rotation direction, which rotates counterclockwise on the paper in FIG. 3, and in the tightening rotation direction, which rotates clockwise on the paper in FIG. 3.

The aforementioned constant contact roller 22 contacts the feed roller 21 at approximately the 2 o'clock position in the illustrated example, and this constant contact roller 22 is rotatably attached to the upper end 25a of a swing arm 25 whose lower end 25b is pivotally supported on the bracket plate 24. The upper end 25a of the swing arm 25 is biased toward the feed roller 21 by a coil spring (not shown), so that the constant contact roller 22 is pressed against the outer periphery of the feed roller 21.

Furthermore, the rotating shaft that rotatably supports the tightening touch roller 23 is attached to a swinging arm 26 that penetrates the rear side of the bracket plate 24 through a long hole (not shown) provided in the bracket plate 24 (see FIG. 4). This swinging arm 26 swings around the support position relative to the bracket plate 24, allowing the tightening touch roller 23 to swing between a spaced position where the tightening touch roller 23 is spaced from the outer periphery of the feed roller 21 and a contact position where the tightening touch roller 23 is in contact with the outer periphery of the feed roller 21.

This swing arm 26 is connected to the plunger of a solenoid 33, which is the driving means for the swing arm 26 (see Figure 4), and is configured so that by turning this solenoid 33 ON and OFF, the swing arm 26 can swing between a contact position where the tightening touch roller 23 is in contact with the feed roller 21 and a separation position where the tightening touch roller 23 is separated from the feed roller 21.

A ratchet gear 27 is attached to the rotation shaft of the feed roller 21 so as to rotate together with the feed roller 21. In this embodiment, the ratchet gear 27 is attached to the rotation shaft of the feed roller 21 on the rear side of the bracket plate 24, between the feed motor 31 and the bracket plate 24 (see Figure 5).

In addition, a locking pawl 28 with a tip 28a that engages with the ratchet gear 27 is provided on the rear side of the bracket plate 24 (see Figure 5). When engaged with this locking pawl 28, the ratchet gear 27, and therefore the feed roller 21, are configured to rotate in the tightening rotation direction but cannot rotate in the supply rotation direction.

The base end 28b side of the locking claw 28 is pivotally supported on the bracket plate 24 described above so that it can swing between an engagement position where the tip 28a is engaged with the ratchet gear 27 and a release position where the tip 28a is separated from the ratchet gear 27 (Figure 5 shows the release position), and is equipped with a spring as a biasing means such as a leaf spring or coil spring (leaf spring 29 in the embodiment) that biases the tip 28a side of the locking claw 28 toward the outer periphery of the ratchet gear 27 in the engagement position.

This locking claw 28 is connected to the aforementioned swing arm 26, which brings the tightening touch roller 23 into contact with or away from the feed roller 21. As a result, when the swing arm 26 moves to the aforementioned contact position, the tip 28a of the locking claw 28 is swung to the aforementioned engagement position where it engages with the ratchet gear 27, and when the swing arm 26 is swung to the aforementioned separation position, the tip 28a of the locking claw 28 can be swung to the aforementioned release position where it is separated from the ratchet gear 27.

The locking claw 28 can be connected to the swing arm 26 by various methods, but in the configuration of this embodiment (see Figure 5), the locking claw 28 is connected to the swing arm 26 via the leaf spring 29 by engaging the end of a biasing means (leaf spring 29 in the embodiment) for biasing the locking claw 28 with a locking fitting 35 provided on the swing arm 26.

[Ceiling unit]
As shown in FIG. 8(A), the sealing unit 40 is equipped with a cam motor 41, a camshaft 42 rotated by the cam motor 41, cams 43a to 43c rotating together with the camshaft 42, and a band end holder (right holder) 44, a loosening prevention holder (left holder) 45, a welding holder (middle holder) 46, and a heater (not shown) operated by the cams 43a to 43c, thereby enabling the band B to be gripped, welded, and cut.

When this sealing unit 40 is in its original position, the right pressure member 44, left pressure member 45, and center pressure member 46 are all in their lowered positions (see Figure 8 (A)).

From this position, the cam motor 41 rotates the camshaft 42, causing the right presser 44 to rise to grip the end of the band [Fig. 8(B)], the left presser 45 to rise to grip the other end of band B [Fig. 8(E)], and the middle presser 46 to rise to weld and cut the band [Fig. 8(G)], after which the right presser 44, left presser 45, and middle presser 46 return to their original lowered positions [Fig. 8(H)].

[Switches]
Furthermore, the packaging machine of the present invention is provided with the following switches (see FIG. 6).

Operation mode selector switch The operation mode selector switch 51 can be operated by a user to select the operation mode to be executed by the packing machine 1 from three patterns: "automatic", "semi-automatic", and "manual". A controller 60 (described later) provided in the packing machine 1 executes each of the controls, "automatic packing control", "semi-automatic packing control", and "manual packing control", which will be described later, in accordance with the selection made by the user by operating the operation mode selector switch 51.

Band insertion detection means (first limit switch)
The band insertion detection means (first limit switch) 52 is arranged at the band end insertion position provided at a predetermined position of the sealing unit 40 described above, and when the tip of the band B is inserted into the predetermined position through a slot hole provided in the table 7 at the start of packaging, it detects this and outputs a detection signal.

In this embodiment, a limit switch is used as the band insertion detection means 52, but it is not limited to a limit switch, and various switches and sensors can be used as the band insertion detection means 52 as long as they can detect the insertion of the band end into the above-mentioned position.

Rotational position detection means (second limit switch)
The rotational position detection means (second limit switch) 53 monitors the rotation of the camshaft 42 and detects the rotational position of the camshaft 42 which is the start timing for each operation. In this embodiment, it detects each of the rotational positions of the "original position" where the right clamp 44, left clamp 45, and middle clamp 46 are all in their lowered positions, the "first detection position" where the right clamp 44 has risen and begun to grip the end of the band, and the "second detection position" where the left clamp 45 has risen and begun to grip the band to prevent it from loosening.

In this embodiment, a limit switch is used as the rotational position detection means 53, but the rotational position detection means 53 is not limited to a limit switch, and various switches and sensors can be used as long as they can detect the rotational position of the camshaft 42 described above.

Manual tightening switch (foot switch 1)
The manual tightening switch 54 is a switch that the user operates when "semi-automatic" or "manual" is selected with the operation mode changeover switch. When the user turns the manual tightening switch 54 ON to tighten the band, the feed motor 31 rotates in the tightening rotation direction, and when the manual tightening switch 54 is turned OFF, the rotation of the feed motor stops.

In this embodiment, the manual tightening switch 54 is a momentary foot switch that is ON only while it is pressed and OFF when released.

Welding start switch (foot switch 2)
The welding start switch 55 is a switch that the user operates when "semi-automatic" or "manual" is selected by the operation mode changeover switch 51. After tightening of the band B is completed, the user operates the welding start switch 55 to command the start of welding, whereby the rotation of the cam motor 41 of the sealing unit 40 resumes, and the left presser foot 45 starts gripping the band, and the middle presser foot 46 starts welding and cutting the band.

In this embodiment, like the manual tightening switch 54 described above, the welding start switch 55 is configured as a momentary foot switch.

Tightening force adjustment switch The tightening force adjustment switch 56 sets the tightening force when tightening the band B. By adjusting the tightening force adjustment switch 56, when "semi-automatic" or "manual" is selected with the operation mode changeover switch 51, the upper limit of the tightening force is adjusted, and when "automatic" is selected, the tightening force value at which tightening ends is adjusted.

Band Feed Length Adjustment Switch The band feed length adjustment switch 57 sets the length of the band to be fed when the band is fed out, regardless of whether the "automatic", "semi-automatic" or "manual" mode is selected.

〔controller〕
The packaging machine 1 is provided with a controller 60 consisting of an electronic control device such as a microcontroller (see FIG. 6). This controller 60 controls the operation of the feed motor 31 and solenoid 33 provided in the roller unit 20 and the cam motor 41 provided in the sealing unit 40 in response to the switching and ON/OFF operation of each of the switches mentioned above.

[Operation description]
The controller 60 of the packaging machine 1 of the present invention described above executes "automatic packing control,""semi-automatic packing control," and "manual packing control," which will be described below, in accordance with the operation mode selected by the operation mode changeover switch 51 described above (see FIG. 7).

[Automatic Packaging Control; see Figures 8 and 9]
(S1-1 to S1-4) Gripping of the Band End When the "automatic" mode is selected by operating the operation mode changeover switch 51 described above, when the tip of the band B is inserted into a predetermined position of the sealing unit 40 through a slot hole provided in the table 7 in the standby state shown in FIG. 8(A), the first limit switch 52, which is the band insertion detection means, is turned ON (FIG. 9; yes in S1-1).

When the first limit switch 52 is turned ON, the controller 60 starts rotating the cam motor 41 of the sealing unit 40 (Figure 9; S1-2), rotating the camshaft 42 and the cams 43a to 43c attached to the camshaft 42, causing the right presser 44 to rise and grip the end of the band B (Figure 8 (B)).

(S1-5 to 6) Pulling Back the Band When the camshaft 42 rotates to a rotational position (first detection position) where the right presser 44 is raised to a position where it grips the end of the band B, the rotational position detection means (second limit switch) 53, which monitors the rotation of the camshaft 42, outputs a detection signal of the first detection position (Fig. 9; yes in S1-3). In response to the detection of this first detection position, the controller 60 stops the rotation of the cam motor 41 of the sealing unit 40 (Fig. 9; S1-4), rotates the feed motor 31 in the tightening rotation direction while keeping the tightening touch roller 23 separated (Fig. 9; S1-5), and pulls back the band until the motor current value rises to a predetermined value and it is detected that the band B has been wrapped around the packaged item W [Fig. 8 (C); (Fig. 9; S1-6)].

Note that this pulling back process does not necessarily have to be performed, and the system may be configured to omit the pulling back process and perform the tightening process described below.

(S1-7 to S1-8) Tightening the band When the band has been pulled back until it is wrapped around the item W to be packaged (FIG. 9; yes in S1-6), the controller 60 actuates the swing arm drive means 33 provided in the roller unit 20 (FIG. 9; S1-7) to bring the tightening touch roller 23 into contact with the outer periphery of the feed roller 21 and begin tightening the band B with the tip 28a of the locking claw 28 engaged with the ratchet gear 27 (FIG. 8 (D)).

The controller 60 monitors the band tightening force (the rotational torque of the feed motor 31) based on the current value of the feed motor 31, etc., and when the tightening force reaches the tightening force preset by the user through operation of the tightening force adjustment switch 56 (Figure 9; yes in S1-8), it stops the rotation of the feed motor 31 (Figure 9; S1-9) and resumes the rotation of the cam motor 41 of the sealing unit 40 (Figure 9; S1-10).

At this time, the rotation of the feed roller 21 in the supply rotation direction is restricted by the engagement of the locking claw 28 with the ratchet gear 27, so even if the feed motor 31 is stopped, the tension of the band B will not rotate the feed roller 21 in the supply rotation direction. Also, since the band B is pressed against the outer periphery of the feed roller 21 by the constant contact touch roller 22 and the tightening touch roller 23, and the contact resistance between the band B and the feed roller 21 is increased, the band is prevented from slipping on the feed roller 21 and becoming loose.

(S1-10) Prevention of loosening of band As described above, when the controller 60 resumes rotation of the cam motor 41, the camshaft 42 and cams 43a to 43c rotate and the left pressure device 45 rises. The supply side end of the band B that has been wound around the outer circumference of the item W to be packaged by the tightening described above is gripped, and the band B is held in a tight state to prevent loosening (Figure 8 (E)).

(S1-11 to 14) Releasing the locking claws As described above, when the camshaft 42 rotates to a rotational position (second detection position) where the left presser foot 45 rises to a position where it begins to grip band B, and the rotational position detection means (second limit switch) 53 detects that the camshaft 42 has rotated to the second detection position (FIG. 9; S1-11: yes), the controller 60 operates the swing arm drive means 33 provided in the roller unit 20 (FIG. 9; S1-12) to swing the swing arm 26 to the separated position, thereby separating the tightening touch roller 23 from the feed roller 21 (FIG. 8 (E)).

Furthermore, when a predetermined time (for example, 50 msec) has elapsed since the detection of the second detection position (Figure 9; yes in S1-13), the feed motor 31 is rotated in the tightening direction for an extremely short period of time (for example, 150 msec) to perform disengagement rotation (Figure 9; S1-14), and even if the locking pawl 28 has not been disengaged from the ratchet gear 27 by the swinging of the swing arm 26 described above, this operation reliably disengages the locking pawl 28 [Figure 8 (F)].

In this way, the left presser 45 is raised to grip the band B so that it does not slacken, and then the swing arm drive means 33 is operated to move the tightening touch roller 23 away from the feed roller 21. Even when the tightening touch roller 23 is moved away, the band B does not slacken and can be maintained in a state of being tightened around the outer periphery of the packaged item W.

When the engagement of the locking pawl 28 with the ratchet gear 27 is released, the feed motor 31, and therefore the ratchet gear 27, is rotated in the tightening rotation direction for a very short time (for example, 150 msec), performing a "disengagement rotation." Even if the feed roller 21 rotates in the supply rotation direction due to the tension of the band B, causing the tip of the locking pawl to be firmly wedged in the tooth groove of the ratchet gear 27, the tip 28a of the locking pawl 28 is naturally pushed out of the tooth groove as the ratchet gear 27 rotates in the tightening rotation direction, and as a result, the engagement of the locking pawl 28 can be easily and reliably released.

(S1-15 to S1-16) Welding of the band. Thereafter, when the cam motor 41 of the sealing unit 40 further rotates, the cam shaft 42 and the cams 43a to 43c rotate, and the middle presser 46 rises, welding and cutting of the band B are performed, and packaging is completed (Figure 8 (G)).

(S1-17 to S1-19) Band feeding. By continuing to rotate the cam motor 41 thereafter, the right pressure member 44, the left pressure member 45, and the middle pressure member 46 all move to the lowered position and return to their original positions, and the rotational position detection means (second limit switch) 53 detects that the camshaft 42 has returned to its original position (FIG. 9; yes in S1-15).

By detecting this original position, the controller 60 stops the rotation of the cam motor 41 (Fig. 9; S1-16) and rotates the feed motor 31 in the supply rotation direction (Fig. 9; S1-17) to feed the band B onto the table 7 (Fig. 8 (H)). After feeding the band for the time corresponding to the length set by the band feed length adjustment switch 57 (Fig. 9; yes in S1-18), it stops the feed motor 31 (Fig. 9; S1-19) and goes into standby mode (Fig. 8 (A)).

In this state, a new packaged item W is placed on the table 7, and the tip of the band B is inserted into a slot hole provided in the table 7. When the band insertion detection means (first limit switch) 52 detects the insertion of the band B (Figure 9; S1-1), the packaging process described above is repeated.

[Semi-automatic packaging control (see Figures 10 and 11)]
Difference from automatic packaging control In the automatic packaging control described above, the end of the band B is inserted and set at a predetermined position in the sealing unit 40, and when the band insertion detection means (first limit switch) 52 detects the insertion of the band B, each of the above-mentioned processes is carried out continuously until packaging is completed.

In contrast, with semi-automatic packaging control, when the retraction of the band is completed, the packaging work stops temporarily and goes into a standby state, and the subsequent tightening and welding of the band is performed in response to the user's operation of the manual tightening switch 54 and manual operation of the welding start switch 55, which is different from the automatic packaging control described above.

(S2-1) Setting the band end Even when the "semi-automatic" mode is selected, when the tip of the band B is inserted into a predetermined position of the sealing unit 40 through a slot hole provided in the table 7, the band insertion detection means (first limit switch) 52 detects the insertion of the band B (Fig. 11; yes in S2-1), and the controller 60 starts rotating the cam motor 41 (Fig. 11; S2-2), raising the right presser 44 to grip the end of the band B, just as when the "automatic" mode is selected [Figs. 10 (A) and (B)].

(S2-2 to 2-6) Pulling back the band Furthermore, when the rotational position detection means (second limit switch) 53 detects that the camshaft 42 has rotated to a rotational position (first detection position) that raises the right retainer 44 to a position where it grips the end of the band B (Figure 11; yes in S2-3), the controller 60 stops the rotation of the cam motor 41 of the sealing unit 40 (Figure 11; S2-4), and rotates the feed motor 31 in the tightening rotation direction with the tightening touch roller 23 separated, so that the band is pulled back until the motor current value rises to a predetermined current value and wrapping of the band B around the packaged item W is detected (Figure 11; S2-5 to 2-6), which is the same process as that during the automatic packaging control described above [Figure 10 (C)].

(S2-7 to 8) Tightening the band However, in semi-automatic packing control, after completing the retraction of band B, the controller 60 temporarily stops the rotation of the feed motor 31 (FIG. 11; S2-7) and activates the swing arm drive means 33 (FIG. 11; S2-8) to bring the tightening touch roller 23 into contact with the feed roller 21 and engage the tip 28a of the locking claw 28 with the ratchet gear 27. In this state, the operation is temporarily stopped and the system goes into a standby state, which differs from automatic packing control in that tightening of the band automatically begins [FIG. 10 (D)].

(2-9 to 10)
In the semi-automatic packing control, when the user turns on the manual tightening switch 54 in this standby state (Figure 11; yes in S2-9), the controller 60 rotates the feed motor 31 in the tightening rotation direction (Figure 11; S2-10) to tighten the band [Figure 10(E)].

(S2-11 to 12)
The controller 60 rotates the feed motor 31 in the tightening direction while the manual tightening switch 54 is ON (Figure 11; S2-11, no), and stops the feed motor 31 when the manual tightening switch 54 is turned OFF (Figure 11; S2-11, yes) or the tightening force preset by the user through operation of the tightening force adjustment switch 56 is reached (S2-11') [Figures 10 (E) and (F): Figure 11; S2-12].

Even after the manual tightening switch 54 is temporarily turned OFF and the feed motor 31 is stopped, the controller 60 will resume rotation of the feed motor 31 in the tightening direction and start tightening when the manual tightening switch 54 is turned ON again until the user operates the welding start switch 55 (Fig. 11; no in S2-13), and then when the manual tightening switch 54 is turned OFF or the tightening force preset by the user through operation of the tightening force adjustment switch 56 is reached (S2-11'), the feed motor 31 will be stopped and the controller 60 will enter a standby state (Fig. 11; S2-9 to S2-12).

(S2-13) Welding of Bands In the automatic packaging control described above, when tightening of the bands is completed with a predetermined tightening force, the controller 60 automatically starts welding of the bands.

In contrast, semi-automatic packaging control differs in that the user operates the welding start switch 55 to command the start of welding, and the controller 60 starts welding the bands.

When the band has been satisfactorily tightened by operating the manual tightening switch 54 described above, the user operates the welding start switch 55 to command the start of welding (Figure 11; yes in S2-13).

(S2-14 to 17)
The controller 60, which has received this welding start command, resumes rotation of the cam motor 41 (FIG. 11; S2-14), which causes the camshaft 42 and cams 43a to 43c to rotate and the left pressure device 45 to rise. The supply-side end of the band B, which has been wrapped around the outer periphery of the item W by the tightening described above, is gripped and held in a tight state so that the band does not loosen (FIG. 10(G)).

As described above, when the camshaft 42 rotates to a rotational position (second detection position) where the left presser 45 rises to a position where it starts gripping the band B, and the rotational position detection means (second limit switch) 53 detects that the camshaft 42 has rotated to the second detection position (Fig. 11; yes in S2-15), the controller 60 operates the swing arm drive means 33 provided in the roller unit 20 (Fig. 11; S2-16) to swing the swing arm 26 to the separated position, separating the tightening touch roller 23 from the feed roller 21 [Fig. 10(G)].

(S2-18 to 19)
Furthermore, after a predetermined time (for example, 50 msec) has elapsed since the detection of the second detection position (FIG. 11; yes in S2-17), a disengagement rotation is performed in which the feed motor 31 rotates in the tightening rotation direction for an extremely short period of time (for example, 150 msec) (FIG. 11; S2-18), and the engagement of the locking pawl 28 with the ratchet gear 27 is released in the case where the engagement is not achieved even by the swinging of the swing arm 26 (FIG. 10(H)).

Then, the sealing unit's cam motor rotates further to rotate the camshaft, and the band ends are welded and cut to complete packaging (Fig. 10(I)). At the same time, the original position is detected (Fig. 11; yes in S2-19), the cam motor 41 is stopped and the band is sent out (Fig. 10(J)), and the system waits until the start of the next packaging process, which is the same as in the case of automatic packaging control described above (Fig. 11; S2-20 to S2-23).

[Manual Packing Control; Figs. 12 and 13; (S3-1 to 20)]
Differences from semi-automatic packaging control In the semi-automatic packaging control described above, when the band insertion detection means (first limit switch) 52 detects the insertion of the band by setting the band end, the right clamp of the sealing unit 40 rises to grip the band end, and then, with the tightening touch roller 23 spaced apart, the feed motor 31 rotates in the tightening rotation direction, so that the band is automatically pulled back.

In contrast, in manual mode, when the band insertion detection means (first limit switch) 52 detects the insertion of band B (Figure 13; yes in S3-1), the controller 60 rotates the cam motor 41 of the sealing unit 40 (Figure 13; S3-2) to raise the right presser 44 and grip the end of the band, which is the same as the semi-automatic packaging control described above [Figures 12 (A) and (B)].

However, in manual packing control, when the right presser 44 finishes gripping the band and the rotational position detection means (second limit switch) 53 detects that the camshaft 42 has rotated to the first rotational position (Fig. 13; S3-3), the controller 60 stops the cam motor 41 of the sealing unit 40 (Fig. 13; S3-4), and instead of pulling back the band with the tightening touch roller 23 separated, as was done in semi-automatic packing control, operates the swing arm drive means 33 (Fig. 13; S3-5) to bring the tightening touch roller 23 into contact with the feed roller 21 and engage the tip 28a of the locking claw 28 with the ratchet gear 27, stops operation in this state, and enters a standby state for subsequent tightening [Fig. 12 (B)].

In this standby state, the user operates the manual tightening switch 54 to start and stop tightening the band [Fig. 12 (C), (D); Fig. 13; S3-6 to S3-9], and when the welding start switch 55 is operated to issue a command to start welding (Fig. 13; yes in S3-10), the rotation of the cam motor 41 is resumed (Fig. 13; S3-11), the left pressure member 45 is raised to prevent loosening of the band and separate the tightening touch roller 23 [Fig. 12 (E)], the engagement is released and the rotation is performed [Fig. 12 (F)], the band is cut and welded [Fig. 12 (G)], and the band is sent out [Fig. 12 (H)], and the system is in a standby state for the start of the next packing process, which is the same as the semi-automatic packing control described above (Fig. 13; S3-12 to S3-20).

1, 1' Packing machine 7 Table 7' Band guide 8 Band reel 20 Roller unit 21 Feed roller 22 Constant contact touch roller 23 Tightening touch roller 24 Bracket plate 25 Swing arm 25a Upper end (of swing arm)
25b Lower end (of swing arm)
26 Swing arm 27 Ratchet gear 28 Engagement claw 28a Tip portion (of the engagement claw)
28b Base end (of the locking claw)
29 Leaf spring (biasing means; spring)
31 Feed motor 33 Swing arm drive means (e.g., solenoid)
35: Locking metal fitting 40: Sealing unit 41: Cam motor 42: Camshaft 43a to 43c: Cam 44: Band end holder (right holder)
45 Anti-loosening presser (left presser)
46 Welding presser foot (middle presser foot)
51 Operation mode changeover switch 52 Band insertion detection means (first limit switch)
53 Rotational position detection means (second limit switch)
54 Manual tightening switch 55 Welding start switch 56 Tightening force adjustment switch 57 Band feed length adjustment switch 60 Controller 100 Packing machine 107 Table 120 Roller unit 121 Feed roller 123 Touch roller 140 Sealing unit 141 Cam motor 142 Camshaft 143a to 143c Cam 144 Right pressure member 145 Left pressure member 146 Center pressure member 152 First limit switch B Band W Packaged item

Claims (10)

A packaging machine having a band reel, a roller unit that pulls out and delivers a band from the band reel and tightens the delivered band, and a sealing unit that grips the band and welds and cuts the band,
The roller unit comprises:
A feed motor;
a feed roller that is selectively rotated by the feed motor in a feed rotation direction in which the band is fed out and a tightening rotation direction in which the band is tightened;
a constant contact roller that is constantly in contact with the outer periphery of the feed roller via the band;
a tightening touch roller that comes into contact with the outer periphery of the feed roller via the band only when the band is tightened;
a swing arm to which the tightening touch roller is rotatably attached and which swings between a contact position where the tightening touch roller contacts the outer periphery of the feed roller and a separation position where the tightening touch roller is separated from the outer periphery of the feed roller;
a swing arm driving means for swinging the swing arm to the contact position when tightening the band, and swinging the swing arm to the separated position after the band is gripped by the sealing unit so that the tightened band does not loosen;
a ratchet gear attached to the feed roller and rotating with the feed roller;
a locking pawl that is pivotally supported between an engagement position where it engages with the ratchet gear and a release position where it is released from engagement with the ratchet gear, and at the engagement position, a tip portion of the locking pawl engages with the ratchet gear to allow rotation of the ratchet gear in the tightening rotation direction, but is provided with a locking pawl that restricts rotation in the supply rotation direction;
A packaging machine characterized in that the locking claw and the swinging arm are connected so that the locking claw is swung to the engagement position when the swinging arm is in the contact position, and the locking claw is swung to the release position when the swinging arm is in the separated position. The packaging machine according to claim 1, further comprising a controller that causes the swing arm drive means to swing the swing arm to the separated position and, simultaneously with or slightly delayed from said operation, causes the feed motor to perform a disengagement rotation in the tightening rotation direction for a very short period of time. The packaging machine according to claim 2, characterized in that the connection between the locking claw and the swinging arm is made via a biasing means. The sealing unit comprises:
A cam motor;
a camshaft rotated by the cam motor;
a cam rotating with the camshaft;
The band end presser operates with the rotation of the cam and holds the tip of the band from before tightening begins until welding is completed, a loosening prevention presser holds the band in a tightened state until welding is completed after tightening the band, and a welding presser performs melting and crimping of the band and cutting it.
a rotational position detection means for detecting a second detection position, which is a rotational position of the camshaft at which the loosening prevention presser of the sealing unit starts to grip the band;
4. A packaging machine according to claim 2 or 3, characterized in that, upon detection of the second detection position by the rotational position detection means, the controller activates the swing arm drive means to swing the swing arm to the separated position, and causes the feed motor to perform the disengagement rotation after a predetermined time has elapsed since the detection of the second detection position. A band insertion detection means is provided for detecting the insertion of the band end into a predetermined position of the sealing unit,
The rotational position detection means is capable of detecting an original position, which is a rotational position of the camshaft where the band end holder, the loosening prevention holder, and the welding holder of the sealing unit are all in an inoperative state, and a first detection position, which is a rotational position of the camshaft where the band end holder starts to grip the band,
The controller,
a band end gripping process in which, upon receiving a detection signal from the band insertion detection means, the rotation of the cam motor is started to cause the band end holder to grip the band end;
a band pulling back process in which the cam motor is stopped when the rotation position detection means detects the first detection position, and the feed motor is rotated in a tightening rotation direction to pull back the band;
a band tightening process in which, after the band is pulled back by the band pulling back process, the swing arm driving means is actuated to swing the swing arm to the contact position and further tighten the band;
a slack prevention process in which, when the tightening force of the band reaches a predetermined tightening force, the feed motor is stopped and the rotation of the cam motor is resumed to grip the band with the slack prevention presser to prevent slack in the band, and, upon detection of the second detection position by the rotation position detection means, the swing arm drive means is operated to swing the swing arm to the separated position;
a disengagement process for causing the feed motor to perform the disengagement rotation after a predetermined time has elapsed since the detection of the second detection position by the rotation position detection means;
The rotation of the cam motor is continued, and the band is welded and cut by the welding presser. Cutting and welding process;
a band delivery process in which, when the rotation position detection means detects the original position, the rotation of the cam motor is stopped and the feed motor is rotated in a supply rotation direction to deliver the band;
a band insertion waiting process in which, after a predetermined length of the band is fed, the rotation of the feed motor is stopped and the process waits until a detection signal is received from the band insertion detection means;
5. The packaging machine according to claim 4, further comprising: Further provided with a manual tightening switch and a welding start switch operated by a user,
The controller, instead of the automatic packing control,
a band end gripping process in which the rotation of the cam motor is started upon receiving a detection signal from the band insertion detection means, and the band end is gripped by the band end holder;
a band pulling back process in which the cam motor is stopped when the rotation position detection means detects the first detection position, and the feed motor is rotated in a tightening rotation direction to pull back the band;
a tightening start standby process, in which after the band is pulled back by the band pull-back process, the feed motor is stopped to end the pull-back and the swing arm drive means is actuated to swing the swing arm to the contact position, thereby entering a tightening start standby state;
A band tightening and standby process in which the feed motor is rotated in a tightening rotation direction by turning on the manual tightening switch, and the rotation of the feed motor is stopped by turning off the manual tightening switch, and the band tightening and standby state is returned to.
a slack prevention process in which, when a welding start command is received from the welding start switch in the tightening start standby state, the rotation of the cam motor is resumed to grip the band with the slack prevention presser to prevent slack in the band, and, upon detection of the second detection position by the rotation position detection means, the swing arm drive means is operated to swing the swing arm to the separated position;
a disengagement process for causing the feed motor to perform the disengagement rotation after a predetermined time has elapsed since the detection of the second detection position by the rotation position detection means;
The rotation of the cam motor is continued, and the band is welded and cut by the welding presser. Cutting and welding process;
a band sending process in which, when the rotation position detection means detects the original position, the rotation of the cam motor is stopped and the feed motor is rotated in a supply rotation direction to send out the band;
a band insertion waiting process in which, after a predetermined length of the band has been fed, the rotation of the feed motor is stopped and the process waits until a detection signal is received from the band insertion detection means;
6. The packaging machine according to claim 5, further comprising: The controller, instead of the semi-automatic packing control,
a band end gripping and tightening start standby process, which starts rotation of the cam motor upon receiving a detection signal from the band insertion detection means, grips the band end with the band end holder, stops the cam motor upon detection of the first detection position by the rotation position detection means, and activates the swing arm drive means to swing the swing arm to the contact position, thereby entering a tightening start standby state;
a band tightening and standby process in which the feed motor is rotated in a tightening rotation direction by turning on the manual tightening switch, and the rotation of the feed motor is stopped by turning off the manual tightening switch, and the band tightening and standby process is resumed.
a slack prevention process in which, when a welding start command is received from the welding start switch in the tightening start standby state, rotation of the cam motor is resumed to grip the band with the slack prevention presser to prevent slack in the band, and, upon detection of the second detection position by the rotation position detection means, the swing arm drive means is operated to swing the swing arm to the separated position;
a disengagement process for causing the feed motor to perform the disengagement rotation after a predetermined time has elapsed since the detection of the second detection position by the rotation position detection means;
The rotation of the cam motor is continued, and the band is welded and cut by the welding presser. Cutting and welding process;
a band sending process in which, when the rotation position detection means detects the original position, the rotation of the cam motor is stopped and the feed motor is rotated in a supply rotation direction to send out the band;
a band insertion waiting process in which, after a predetermined length of the band is fed, the rotation of the feed motor is stopped and the process waits in this state until a detection signal is received from the band insertion detection means;
7. The packaging machine according to claim 6, further comprising: Further provided with a manual tightening switch, a welding start switch, and an operation mode changeover switch operated by a user,
6. The packaging machine according to claim 5 , wherein the controller executes the automatic packaging control in accordance with a selection made by a user by operating the operation mode changeover switch. Further provided with a manual tightening switch, a welding start switch, and an operation mode changeover switch operated by a user,
7. The packaging machine according to claim 6, wherein the controller executes the semi-automatic packaging control in accordance with a selection made by a user by operating the operation mode changeover switch. Further provided with a manual tightening switch, a welding start switch, and an operation mode changeover switch operated by a user,
8. The packaging machine according to claim 7, wherein the controller executes the manual packaging control in accordance with a selection made by a user by operating the operation mode changeover switch.

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