Labella

Abstract

To contactlessly detect gaps between an applicator head and a label holder and automatically adjust distances between the applicator head and the label holder.SOLUTION: A labeler includes a label adhering drum 22 that suction-holds labels on the outer peripheral surface of the drum and conveys the labels, a glue supply device 36 that applies glue to the label being conveyed, a spacing adjustment device that adjusts the distance between the outer peripheral surface of the label adhering drum 22 and the glue supply device 36, a camera 41 that photographs the gap between a label holding part 23 of the label adhering drum 22 and an applicator head 37 provided on the glue supply device 36, and detection means 45 for detecting the distance between the applicator head 37 and the label holding part 23 based on the images taken by the camera 41. The detection means 45 detects the spacing between the label holding part 23 and the applicator head 37 from the images taken by the camera 41 when the label adhering drum 22 is stopped, and based on the spacing, controls the operation of the spacing adjustment device so that the label holding part 23 and the applicator head 37 are spaced as predetermined.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to a labeling machine that applies glue to the back surface of a label to be attached to the outer peripheral surface of an article and attaches the label to a container.

Background Art

[0002] There is known a labeling machine that cuts a fed long label into a predetermined length, applies glue to the back surface, and attaches it to the outer peripheral surface of a container (Patent Document 1). In the labeling machine disclosed in Patent Document 1, the cut label is held backward by a label holding portion disposed on the outer periphery of a transfer drum, and glue is discharged from an application head disposed adjacent to the outer periphery of the transfer drum while the label is conveyed along the outer periphery, and applied to the back surface of each label.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004]

[0005] However, in conventional gap adjustment processes, the application head comes into contact with the label holder during the process of bringing the application head closer to the label holder. As a result, adhesive may adhere to the label holder, requiring cleaning before the labeling process begins. Furthermore, if hot melt adhesive is used, the heat from the application head approaching the label holder may cause the pad on the label holder to expand, potentially causing the gap adjustment to deviate from the correct value. In addition, the accuracy of manual adjustment work is affected by the skill of the operator.

[0006] The present invention aims to detect the gap between the coating head and the label holding unit in a non-contact manner and to automatically adjust the distance between the coating head and the label holding unit. [Means for solving the problem]

[0007] The labeler of the present invention is a labeler for attaching labels to a container comprising: a label-attaching drum capable of suction-holding and transporting labels on the outer circumferential surface of the drum; an adhesive application means capable of applying adhesive to labels being transported by the label-attaching drum at a predetermined application position; and a spacing adjustment device capable of adjusting the distance between the outer circumferential surface of the label-attaching drum and the adhesive application means, wherein the labeler comprises: an imaging device for photographing the gap between the label-holding portion of the label-attaching drum and the application head provided on the adhesive application means; a detection means for detecting the distance based on the image captured by the imaging device; and a control device capable of controlling the operation of the spacing adjustment device, wherein the detection means detects the distance between the label-holding portion and the adhesive application means from the image captured by the imaging device when the label-attaching drum is stopped, and the control device controls the operation of the spacing adjustment device so that the label-holding portion and the adhesive application means are at a predetermined distance based on the detected distance. [Effects of the Invention]

[0008] According to the present invention, the gap between the coating head and the label holding unit can be detected non-contactually, and the distance between the coating head and the label holding unit can be automatically adjusted. [Brief explanation of the drawing]

[0009] [Figure 1] This is a plan view showing the arrangement of a roll labeler using a label adhesive application apparatus, which is one embodiment of the present invention. [Figure 2] This is a longitudinal cross-sectional view of a label adhesive application apparatus along section AA in Figure 1. [Figure 3] This is a schematic plan view of a label adhesive application device around the application head, showing the placement of lighting and cameras. [Figure 4] This is a schematic diagram of the image captured by the camera during the spacing adjustment process of this embodiment. [Modes for carrying out the invention]

[0010] Hereinafter, embodiments of the present invention will be described with reference to the drawings. Figure 1 is a plan view showing the arrangement of a roll labeler using a label adhesive application apparatus which is one embodiment of the present invention.

[0011] The roll labeler 10 of this embodiment attaches labels L to the sides of articles such as containers V. The containers V are transported in a single line on the supply conveyor 12, and after the transport pitch is adjusted by an infeed screw 14 provided downstream of the supply conveyor 12, they are transferred to the rotary table 18 via a supply star wheel 16. The label application drum 22 of the label adhesive application device 20 of this embodiment is positioned adjacent to the outer circumference of the rotary table 18.

[0012] The label-applying drum 22 rotates in sync with the rotary table 18, and applies adhesive-coated single-sheet labels L to the sides of containers V that are being transported along the outer circumference of the rotary table 18. Containers V with labels L attached to their sides are then transferred to the discharge conveyor 26 via the discharge star wheel 24 and discharged downstream. The supply star wheel 16, rotary table 18, and discharge star wheel 24 also rotate in sync.

[0013] The label application drum 22 of the label adhesive application device 20 is equipped with multiple label holding sections 23 along its outer circumference, each holding and transporting a cut sheet of labels L. The labels L are fed out as long sheets from a raw material roll (not shown) and supplied to a backup roller 30 via multiple rollers 28. A rotary cutter 32 is positioned adjacent to the backup roller 30, and the long sheet of labels L is cut to a predetermined length by the rotary cutter 32 to form individual sheets of labels L. The cut labels L are then transferred to the label holding sections 23 of the label application drum 22 via a transfer drum 34.

[0014] The single-sheet labels L, transferred from the transfer drum 34 to the label application drum 22, are held face down by the label holding unit 23 and transported along the outer circumference of the drum. The label application drum 22 has an adhesive supply device (adhesive application means) 36 with an application head (gun head) 37 positioned adjacent to the outer circumference of the drum. In this embodiment, hot melt adhesive is used and supplied to the application head 37 in a heated state. Therefore, the application head 37 is also at a high temperature. As the label holding unit 23 travels in front of the application head 37, adhesive is supplied from the application head 37 to the back surface of the label L held by the label holding unit 23 and applied to a uniform thickness. The adhesive-coated labels L are pressed against the side of the container V, which is transported by the rotary table 18, by the label holding unit 23 and attached.

[0015] The label adhesive application apparatus 20 of this embodiment includes a spacing adjustment device 38 for adjusting the size (spacing) of the gap between the tip of the application head 37 and the label holding surface of the label holding portion 23 of the label application drum 22. The spacing adjustment device 38 is controlled based on signals from a detection means 45 using illumination 40 and a camera (imaging device) 41, which will be described later.

[0016] Figure 2 is a longitudinal cross-sectional view of the label adhesive application device 20 along the AA section of Figure 1, and Figure 3 is a schematic plan view of the label adhesive application device 20 around the application head 37 showing the arrangement of the lighting 40 and camera 41.

[0017] As described above, a plurality of label holding portions 23 are arranged along the outer periphery around the label - attaching drum 22. One label holding portion 23 includes a front pad 23A that sucks and holds the leading edge of the sheet - like label L, and a rear pad 23B that sucks and holds the trailing edge. Suction portions 42 made of rubber pads are provided at the leading edge portion of the front pad 23A and the trailing edge portion of the rear pad 23B, respectively. The suction portion 42 is provided with a plurality of suction ports 42A that are dispersed vertically, horizontally, and diagonally. The suction ports 42A communicate with an intake pipe 44 through an intake passage 42B provided in the front pad 23A and the rear pad 23B. The intake pipe 44 is connected to a vacuum device (not shown), and air is sucked from each suction port 42A of the label holding portion 23. That is, the sheet - like label L supplied from the transfer drum 34 is adsorbed and held at its leading edge and trailing edge by the suction portion 42 in each label holding portion 23.

[0018] Each label holding portion 23 is radially attached around a rotating shaft 43, and the rotating shaft 43 is rotatably supported by a base plate 48. The rotating shaft 43 is rotated in synchronization with the rotary table 18 and the transfer drum 34 by a driving portion (not shown).

[0019] An application head 37 is arranged adjacent to the label - holding surface of the label holding portion 23 on the outer peripheral portion of the label - attaching drum 22. A glue discharge port is provided at the tip of the application head 37 corresponding to the size of the label L, and glue is supplied from a glue storage portion 37B through a glue passage 37A. The glue discharged from the discharge port is applied to the back surface of the label L held and conveyed by the label holding portion 23 with a predetermined thickness.

[0020] As shown in FIG. 2, the glue supply device 36 including the application head 37 is movable forward and backward along the radial direction of the label - attaching drum 22 by a gap adjustment device 38. The gap adjustment device 38 includes, for example, a slider 38A along the radial direction of the label - attaching drum 22, and the glue supply device 36 mounted on the slider 38A is moved forward and backward along the slider 38A by a servo - motor 38B. The servo - motor 38B is controlled by a control device 46 based on the output from the inspection means 45.

[0021] The illuminator 40 and the camera 41 are arranged so as to sandwich the coating head 37 along the substantially outer peripheral tangent direction of the labeling drum 22. The lens of the camera 41 is arranged facing the illuminator 40, and the camera 41 can photograph the tip of the coating head 37 and the outer peripheral portion of the labeling drum 22.

[0022] FIG. 4 is a schematic diagram of an image photographed by the camera 41 in the interval adjustment operation of the present embodiment. The interval adjustment operation in the present embodiment will be described with reference to FIG. 4.

[0023] The interval adjustment operation between the labeling drum 22 and the coating head 37 using the interval adjustment device 38 of the present embodiment is performed before the start of production with the suction portion 42 of the label holding portion 23 made to face the coating head 37 and the labeling drum 22 stopped. With the position of the labeling drum 22 fixed, the coating head 37 is moved by the interval adjustment device 38 to a predetermined initial position at least a certain distance away from the suction portion 42. Thereafter, with the illuminator 40 irradiating, the gap between the suction portion 42 of the labeling drum 22 and the coating head 37 is photographed by the camera, and the image shown in FIG. 4 is obtained. The photographed image is sent to the detection means 45.

[0024] In the photographed image, as shown in FIG. 4, the coating head 37 and the suction portion 42 facing each other across the gap are photographed. In the detection means 45, image processing (such as binarization etc.) is performed so that the boundary between the coating head 37 and the suction portion 42 constituting the gap becomes clear, and the number of pixels between the coating head 37 and the suction portion 42 is detected based on the image. Based on the detected number of pixels, the size of the gap is calculated from the relationship between one pixel and the distance specified in advance. The calculated size (interval) of the gap is sent to the control device 46, and the control device 46 drives the interval adjustment device 38 based on the calculated size of the gap, and moves the tip of the coating head 37 to a position a predetermined distance (for example, 50 μm) away from the suction portion 42 set in advance. Thereby, the gap between the coating head 37 and the label holding portion 23 is set to an appropriate interval and the interval adjustment operation ends.

[0025] T As described above, the label adhesive application apparatus of this embodiment can use camera images to detect the gap between the application head and the label holding unit non-contact, and automatically adjust the distance between the application head and the label holding unit. This allows the distance adjustment work to be performed without being affected by the heat generated by the application head on the label holding unit or by the skill of the operator.

[0026] In this embodiment, a roll labeler was used as an example, but the labeler is not limited to this; for example, a sheet-fed labeler may also be used. [Explanation of Symbols]

[0027] 10 Labella 20 Label adhesive application device 22 Label-applied drums 23 Label holding section 36 Glue supply device (glue application means) 40 Lighting 41. Camera (imaging device) 45 Detection means 46 Control device L Label V Container (article)

Claims

[Claim 1] A label-applying drum capable of suction-holding and transporting labels on the outer surface of the drum, An adhesive application means capable of applying adhesive to labels being transported by the label application drum at a predetermined application position, A labeling tool for applying labels to a container, which is equipped with a spacing adjustment device that can adjust the distance between the outer surface of the labeling drum and the adhesive application means, An imaging device for photographing the gap between the label holding portion of the label application drum and the application head provided on the adhesive application means, A detection means for detecting the interval based on an image captured by the imaging device, The device comprises a control device capable of controlling the operation of the interval adjustment device, The detection means detects the distance between the label holding unit and the adhesive application means from the image captured by the imaging device when the label application drum is stopped. The control device controls the operation of the spacing adjustment device so that the label holding unit and the adhesive application means are at a predetermined distance from each other, based on the detected interval. A labella characterized by the following features.

Images