JPH01279037A - Apparatus and method for correcting positional shift of label - Google Patents

Abstract

PURPOSE:To bring a label attaching pitch and a container conveying pitch into a synchronous relation, by obtaining with an angle sensor the displacement in the rotating angle of a label attaching drum against the container conveying pitch and computing an out-of-phase between the displacement in this drum rotating angle and a predetermined drum rotating angle. CONSTITUTION:Labels are successively fed from a label magazine 8 onto a label retaining jig and, after application thereto of an adhesive by an adhesive roller 1, the label is attached to a predetermined location of a container 5 on a moving conveyor. On label attachment, in the case of the failure to bring the container 5 and the the head of label retaining jig 15 into synchronous relationship resulting from the improperly gripped container 5 on the conveyor and a backlash caused by the wear of drive means, a phase adjustment differential gear 13 is placed in operation to correct the amount of a shift therebetween on the basis of relative shift amount between the container 5 and the head of the label retaining jig 15 computed at each conveying pitch through a photosensor 10 provided on the conveyor. The container 5 with the label is then pressed at a compression part 4 by a label hold-down compression pad.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a correction device and a correction method for correcting misalignment of a label in the process of pasting a label on a predetermined position of a container such as a bottle.

[Prior Art] Conventionally, in a label pasting device for pasting labels on containers such as bottles, a container positioning mechanism that synchronizes with the rotation of a label pasting drum, such as a mechanically synchronized screw mechanism, is used as a positioning part. By setting the conveyor interval on the conveyor that conveys the containers, the position where the label is attached on the container is determined relative to the pasting drum, and the container is conveyed to the labeling station. There is.

At this labeling station, a label is taken out from a label magazine onto a label pasting drum, pasted with glue on the back side of the label by a pasting roller, and then temporarily pasted onto a transported container. Next, this temporarily attached label is appropriately pressed and finished by a label presser compression pad in a compression section. These series of operations are performed by a drive system mechanically connected to a single power source.

[Problems to be Solved by the Invention] In the conventional mechanism described above, positioning of the container is an important element in a series of labeling processes, and the positioning of the container is The structure is such that normal labeling is performed only when the relative positions of the two are set accurately.

However, in the conventional technology, the position of the container with respect to the label holding jig is not accurately synchronized due to misalignment of the grip state of the container on the conveyor, backlash of the machine, etc. If the labeling is shifted to the right or left, defective products will be produced.

Therefore, the present invention relates to a positioning mechanism in a labeling process for containers, etc., and a positional misalignment correction device and method for correcting relative misalignment of a container with respect to a labeling station for accurate positioning in order to enable appropriate labeling. The purpose is to provide

[Means for Solving the Problems] In order to achieve the above object, the present invention provides a labeling drum for pasting labels on containers conveyed at predetermined intervals, and a container conveying interval between the labeling drums. A phase shift detection means for detecting a relative phase shift between a corresponding predetermined pasting interval and a container transport interval, and a container transport system for pasting a label at a predetermined position on a container based on a phase shift signal from the detection means. A label position deviation correcting device is provided which includes a phase deviation adjustment means for synchronizing the interval and the label attachment interval. Further, it is preferable that the phase shift detection means comprises a conveyance interval measurement sensor that measures the conveyance interval of the containers and an angle sensor that measures the rotation angle of the label application drum.

The phase shift adjustment means uses an angle sensor to obtain the rotational angular displacement of the label pasting drum corresponding to the container conveyance interval based on the sensor signal of the conveyance interval measurement sensor for each container conveyance interval, It is also possible to calculate the amount of phase shift by comparing the rotation angle with a predetermined drum rotation angle, and use a differential gear to synchronize the label pasting interval of the label pasting drum and the container conveyance interval, thereby measuring the container conveyance interval. It is preferable that the sensor is a photo sensor and the angle sensor is a rotary encoder.

Further, according to the present invention, in a method for correcting a relative phase shift between a conveyance interval of containers conveyed at a predetermined interval and a label pasting interval at which labels are pasted according to this conveyance interval, the container conveyance interval is measured. Then, by comparing this conveyance interval and a predetermined label pasting interval, the relative phase shift amount is calculated, and based on this phase shift value, the container conveyance interval and label pasting interval are calculated in order to paste the label at a predetermined position on the container. A method for correcting a label position deviation is provided in which the amount of phase deviation is corrected so that the labeling interval is synchronized.

The comparison between the container transport interval and the label pasting interval is preferably determined by measuring the label pasting interval corresponding to the container transport interval and calculating the difference between this measured interval and a predetermined label pasting interval. .

[Action Co. The means for solving the above-mentioned problem works as follows.

Containers are transported at predetermined intervals, and the transport interval is measured by a transport interval measuring sensor, and the rotational angular displacement of the labeling drum at that time is read by an angle sensor. In this case, if the conveyance interval deviates from the predetermined interval, the pasting phase difference that occurs between the label pasting interval of the label pasting drum that sticks the label on the container in synchronization with the predetermined container conveyance interval. is determined, and preferably the container transport interval and the labeling interval are synchronized via mechanical means.

[Embodiments] Hereinafter, embodiments of the present invention will be described in detail based on the accompanying drawings.

In FIG. 1, a boat-type labeling device is shown.

This pasting device is part of the population screw! , a conveyor 2, a labeling station 3, and a combiner unit 4.

The containers 5 are positioned at regular intervals on the transport conveyor 2 by the inlet screw part l and are transported to the labeling station 3 . At the labeling station 3, the label holding jig 15 is attached to the label pasting drum 1.
2, the containers are placed at, for example, six equal intervals around the circumference of the drum, and the labels are sequentially supplied from the label magazine 8 onto the holding jig, pasted by the glue roller 16, and then conveyed. 5 is labeled at a predetermined position. In this series of operations, the labeling drum and the inlet screw unit 1 are rotated synchronously by the drive motor 6 via the main shaft 14 to determine the conveyance interval of the containers 5 on the conveyor, and the labeling station 3 sequentially and accurately Labeling is performed.

During this labeling, if the container 5 and the head of the label holding jig 15 are not synchronized well due to misalignment of the grip state of the container 5 on the conveyor or backlash caused by wear of the drive system, a Container 5 and label holding jig calculated for each conveyance pitch via the photo sensor IO! Based on the amount of relative positional deviation with respect to the head No. 5, the phase adjustment differential gear 13 is operated to correct the amount of deviation. Next, this labeled container 5 is pressed by a label pressing compression pad in the compression section 4, and a series of label pasting steps is completed.

Hereinafter, the synchronization correction mechanism described above will be further explained in detail with reference to FIG.

In the labeling station 3, the label pasting drum 12 is provided with a rotary encoder II, and the rotary encoder II
, B, 2', and phase pulse signals are sent to the controller 9. Next, a rotary encoder interface circuit (not shown) provided in the controller 9 detects the change edge of the A and B phases of this pulse signal.
The frequency is four times that of the rotary encoder and is counted by a 16-bit subtraction counter. Then, at the first edge of the Z-phase pulse, the CPU is interrupted and the down counter is cleared to 0 via software. Therefore, the encoder value is meaningless until the first Z-phase pulse is input, and nothing is displayed on the control panel during this time.

The subtraction counter counts P every revolution of the label pasting drum.
(for example, 14,400 pulses) are applied to the human body,
It takes a value of 0 to -(P-1) (0 to = 14399). When a container 5 is transported into the detection range of the photosensor 10, a signal from the sensor interrupts the CPU each time the container 5 passes, and the value of the subtraction counter at that time is read.
By taking the two's complement of this value, the rotational phase of the label pasting drum 12 can be set from 0 to (pt) (o to 14399).
can be obtained as an integer value. Now set that value to RF
Then, the phase difference (R) between the pasting position one pitch before when the photosensor 10 detects the container 5 and the position of the head of the label holding jig is determined by the following equation.

R=Mop (RE/P/number of heads) (1) That is, R is the remainder when the number of RFX heads is divided by P.

However, due to the installation error of the encoder, the difference between the photo sensor installation position and the pasting position, and the difference in detection position depending on the type of container, etc., this R
It is necessary to correct it by adding a certain value to it. Therefore, assuming that this constant value is C, the actual deviation E between the heads of the container 5 and the label holding jig 15 is obtained as follows: E=r(-C...(2)).

Once the deviation E is determined, a number of pulses corresponding to the deviation E are outputted to the motor drive system of the servo motor 7. Here, there is a relationship between the human power pulse from the low-return encoder 11 and the output pulse to the motor drive system.

(1 week's worth of input pulses/1 week's worth of output pulses) - (P/
Q) As a result, the number of output pulses to the servo motor drive system for the deviation E is Y-(P/Q) E...(3), and the servo motor 7 is driven by this number of pulses, which is used for phase adjustment. The label sticking drum is rotated by the differential gear 13, and the misalignment between the container 5 and the head of the label holding jig is corrected. This series of phase shift correction control is repeated for each conveyance pitch of containers conveyed at predetermined intervals, so that constant labeling is always performed.

- If the photosensor 10 malfunctions or the container position is in an abnormal state exceeding the control range, the output Y will be terminated at the number of pulses when it exceeds the number of pulses corresponding to ±Itlxl to protect the mechanical system. is desirable. In addition, if the deviation E is a small amount, because frequent correction operations will significantly shorten the life of the drive system due to causes such as wear,
If the absolute value of the deviation E is within a certain value M, the output value Y
It is preferable that the correction mechanism is not operated by not calculating and outputting pulses.

Furthermore, in consideration of the backlash of the phase adjustment differential gear 13, it is also possible to add the following functions in order to perform more accurate correction.

That is, the following equation is used in place of the above equation (3).

In the case of Yb>O and E>O, Y= (P/Q)・
In the case of E yb>o and E<O, Y= (P/Q
)・(E-B) In case of Yb<O and E>O, Y= (P/Q)
・ (E+B) If yb<o and Eku0, then Y= (P/
Q)・E Here, Yb is the number of output pulses when the previous correction operation was performed, and B is the rotary correction of the gear backlash that causes an error when the phase adjustment differential gear 13 reverses. This is a value converted to the number of input pulses from the encoder 11, and is a unique value determined by the type of differential gear 13.

As described above, this device calculates the amount of deviation by measuring the pitch interval of containers on the conveyor, and adjusts the rotation angle of the labeling drum via a differential gear. However, the present invention is not limited to the above-described configuration particularly regarding the container transport mechanism,
For example, in a rotary type label pasting device as shown in Fig. 3, a differential gear is provided on the container conveyance table +7, and the table angle is 1i1JalL to adjust the phase shift between the head of the label holding jig and the container. It is also possible.

[Effects of the Invention] A unique effect of the present invention is that due to backlash and other vibrations caused by wear of the drive system of the labeling device, it is difficult to print labels according to the conveyance interval of containers and the intervals. Even if there is a discrepancy in the label pasting timing, constant and accurate labeling is possible by accurately detecting the entire discrepancy and making corrections for each container transport interval.

Therefore, the number of defective products due to label misalignment is significantly reduced, and productivity is improved.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing an embodiment of a label pasting device according to the present invention. FIG. 2 is an explanatory diagram showing the phase shift between the container conveyance interval and the label pasting drum. FIG. 3 is a schematic diagram showing another embodiment of the labeling device.

Claims (7)

[Claims] (1) Detecting the relative phase difference between the labeling drum that pastes labels on containers transported at predetermined intervals, and the predetermined pasting interval corresponding to the container transporting interval of the labeling drum and the container transporting interval. a phase shift detection means for
Label position deviation correction characterized by comprising a phase deviation adjustment means for synchronizing a container conveyance interval and a label application interval in order to apply a label to a predetermined position of a container based on a phase deviation signal from the detection means. Device. (2) The label according to claim 1, wherein the phase shift detection means comprises a conveyance interval measurement sensor that measures the conveyance interval of the containers and an angle sensor that measures the rotation angle of the label pasting drum. Misalignment correction device. (3) The phase shift adjustment means obtains, with the angle sensor, a rotational angular displacement of the labeling drum corresponding to the container transport interval based on a sensor signal of the transport interval measurement sensor for each container transport interval, A phase shift amount is calculated by comparing the drum rotation angle displacement with a predetermined drum rotation angle, and the label pasting interval of the label pasting drum and the container conveyance interval are synchronized via a differential gear. A label misalignment correcting device according to claim 2. (4) The label misalignment correcting device according to claim 3, wherein the sensor for measuring the container conveyance interval is a photo sensor. (5) The label misalignment correcting device according to claim 3, wherein the angle sensor is a rotary encoder. (6) In a method for correcting a relative phase shift between the conveyance interval of containers conveyed at predetermined intervals and the label pasting interval at which labels are pasted according to the conveyance interval, the container conveyance interval is measured, and the conveyance interval is and a predetermined label pasting interval to calculate the relative phase shift amount, and based on the phase shift amount, the container transport interval and the label pasting interval are synchronized in order to paste the label at a predetermined position on the container. A label position deviation correction method for correcting the amount of phase deviation. (7) The comparison between the container conveyance interval and the label pasting interval is characterized in that the label pasting interval corresponding to the container conveying interval is measured, and the difference between the measured interval and a predetermined label pasting interval is calculated. 7. The method for correcting label misalignment according to claim 6.