Remote registration feedback pressure sensor assembly for improved print quality

Abstract

The can decorator comprises a blanket wheel having a plurality of blankets arranged on its outer circumference, a plate cylinder for an inking station configured to rotate in contact with the blanket wheel, a mandrel configured to hold a can and rotate in contact with the blanket wheel, and a pressure sensor configured to sense the pressure between the plate cylinder and the blanket wheel, or between the mandrel and the blanket wheel.

Description

Technical Field

[0001] <Cross - reference to Related Applications> This application claims priority to U.S. Patent Application No. 18 / 140,674, titled "Remote Registration Feedback Pressure Sensor Assembly For Improved Print Quality", filed on April 28, 2023.

[0002] The concepts of the present disclosure generally relate to can decorators used in the food and beverage packaging industry, and more specifically, to pressure sensors for can decorators.

Background Art

[0003] High - speed continuous - operation machines for decorating cans, generally referred to as "can decorator machines" or simply "can decorators", are well - known. FIG. 1 shows a can decorator 2. As shown in FIG. 1, the can decorator 2 includes an infeed conveyor 15 that receives cans 16 from a can supply device (not shown) and guides them to arcuate cradles or pockets 17 provided along the periphery of spaced - apart parallel rings fixed to a pocket wheel 12. The pocket wheel 12 is fixed to a continuously rotating mandrel carrier wheel 18, and the mandrel carrier wheel 18 is keyed to a continuously rotating horizontal drive shaft 19. Horizontal spindles or mandrels (not shown), each of which is pivotable about its own axis, are attached adjacent to the periphery of the mandrel carrier wheel 18. Downstream of the infeed conveyor 15, each spindle or mandrel is axially aligned in close proximity to an individual pocket 17, and the undecorated cans 16 are sent from the pockets 17 to the mandrels. The suction force applied through the axial passage of the mandrel draws the cans 16 to their final seating positions on the mandrels.

[0004] While mounted on the mandrel, each can 16 is decorated by engaging with a blanket (e.g., a replaceable adhesive rubber piece, but not limited to one) positioned on the blanket wheel of a multicolor printing unit, indicated collectively by reference numeral 22. Then, while still mounted on the mandrel, the outside of each decorated can 16 is coated with a protective film of varnish applied by engaging with the periphery of a varnish application roll (not shown) rotating around the shaft 23 of an over-varnish unit, indicated collectively by reference numeral 24. The decorated and protectively coated cans 16 are then transferred from the mandrel to a suction cup (not shown) mounted adjacent to the periphery of a transfer wheel (not shown) rotating around the shaft 28 of a transfer unit 27. From the transfer unit 27, the cans 16 are placed on a nearly horizontal pin 29, which is carried by a chain-type discharge conveyor 30, which transports the cans 16 through a curing oven (not shown).

[0005] As the blanket wheel moves toward engagement with the undecorated can 16, it engages with multiple plate cylinders 31. Each plate cylinder 31 is associated with an individual inking station 32 (Figure 1 shows eight exemplary inking stations 32). Typically, each inking station 32 provides a different color of ink, and each plate cylinder 31 applies a different ink image segment to the blanket. All of the "ink image" segments are combined to produce a "main image" configured to be applied to the can body. The "main image" is then transferred to the undecorated can 16, becoming what is referred to herein as the "can body applied image".

[0006] Each inking station 32 includes several rollers, or "rolls" as defined herein, which are configured to transfer a certain amount of ink from a reservoir, or "ink fountain" as defined herein, to a blanket. The path through which the ink travels is identified herein as the "ink train." That is, the rollers through which the ink travels define the "ink train." Furthermore, as described herein, the "ink train" is directional, with the ink fountain at the "upstream" end of the ink train and the plate cylinder 31 at the "downstream" end of the ink train.

[0007] The ink train extends across several rolls, each with its own purpose. As illustrated, the ink train begins with an ink reservoir and is first applied as a film to the fountain roll. The ductor roll intermittently engages with the fountain roll. When the ductor roll engages with the fountain roll, a certain amount of ink is transferred to the ductor roll. The ductor roll also intermittently engages with downstream rolls, transferring ink there. The ductor roll has a "duty cycle." In this specification, this means the ratio of the duration the ductor roll is in contact with the fountain roll to the duration of a complete cycle (the ductor roller in contact with the fountain roll, moving to the first downstream roller, in contact with the first steel roller, and returning to the fountain roll).

[0008] Other rolls include, but are not limited to, distribution rolls, oscillator rolls, and transfer rolls. Generally, these rolls are configured to distribute ink so that the appropriate amount of ink is applied to the plate cylinder 31 in a generally uniform manner. For example, an oscillator roll is configured to reciprocate longitudinally around its axis of rotation to spread the ink when it is applied to the next downstream roll. The final roll is the plate cylinder 31, which applies the ink to the blanket. It is understood that each inking station 32 applies a selected single-color "ink image" to the blanket, and that each inking station 32 must position its ink image appropriately relative to other ink images so that there is no offset of the ink image in the main image.

[0009] Pressure is also related to the proper application of ink images. Too much or too little pressure will affect the quality of the ink image. In current can decorators, the best available information regarding pressure is provided in the form of distance measurements between the relevant printing surfaces. However, clearance distance is not a perfectly accurate or complete indicator of pressure.

[0010] There is still room for improvement in the can decorator. [Overview of the project]

[0011] According to one aspect of the concept of the present disclosure, a can decorator comprises a blanket wheel having a plurality of blankets arranged on its outer circumference; a plate cylinder for an inking station, configured to rotate in contact with the blanket wheel; a mandrel for holding a can and configured to rotate in contact with the blanket wheel; and a pressure sensor configured to sense the pressure between the plate cylinder and the blanket wheel, or between the mandrel and the blanket wheel.

[0012] According to one aspect of the concept of the present disclosure, a method for adjusting pressure in a can decorator having a blanket wheel having a plurality of blankets arranged on its outer circumference, a plate cylinder for an inking station configured to rotate in contact with the blanket wheel, and a mandrel configured to hold a can and to rotate in contact with the blanket wheel, includes providing a pressure sensor configured to sense the pressure between the plate cylinder and the blanket wheel, or between the mandrel and the blanket wheel, sensing a first pressure between the plate cylinder and the blanket wheel, or between the mandrel and the blanket wheel, determining a target pressure, and adjusting the position of at least one of the plate cylinder, the blanket wheel, and the mandrel so that the first pressure is adjusted to the target pressure. [Brief explanation of the drawing]

[0013] A complete understanding of the present invention can be obtained by reading the following description of preferred embodiments in conjunction with the accompanying drawings.

[0014] [Figure 1] This is an elevation view of a can decorator.

[0015] [Figure 2] This figure shows a plate cylinder and blanket wheel of a can decorator including a pressure sensor, according to an exemplary embodiment of the concept of the present disclosure.

[0016] [Figure 3] This figure shows a blanket wheel and mandrel of a can decorator having a pressure sensor, according to an exemplary embodiment of the concept of the present disclosure.

[0017] [Figure 4] This figure shows a blanket wheel and mandrel of a can decorator having a pressure sensor, according to an exemplary embodiment of the concept of the present disclosure.

[0018] [Figure 5]This is a schematic diagram of a printing cylinder including a pressure sensor according to an exemplary embodiment of the concept of the present disclosure.

[0019] [Figure 6] This is a schematic diagram of a printing cylinder including a pressure sensor according to an exemplary embodiment of the concept of the present disclosure. [Modes for carrying out the invention]

[0020] Figure 2 shows a plate cylinder 100 and a blanket wheel 110 according to an exemplary embodiment of the concept of the present disclosure, wherein a pressure sensor 120 is provided to sense the pressure between the plate cylinder 100 and the blanket wheel 110. For the sake of saving disclosure, the pressure sensor 120 is shown on both the plate cylinder 100 and the blanket wheel 110. However, it will be understood that without departing from the scope of the concept of the present disclosure, the pressure sensor 120 may be included on only one of the plate cylinder 100 and the blanket wheel 110.

[0021] The plate cylinder 100 and the blanket wheel 110 roll into contact with each other. Their contact location is sometimes referred to as a nip. The pressure sensor 120 is configured to sense the pressure at the nip where the plate cylinder 100 and the blanket wheel 110 are in contact. In some embodiments, the pressure sensor 120 is configured to continuously sense the pressure at the nip. In some embodiments, the pressure sensor is configured to intermittently sense the pressure at the nip. In an exemplary embodiment where the pressure sensor 120 is disposed on the plate cylinder 100, the pressure sensor 120 may extend over the entire length of the plate cylinder 100 or a part of the entire length of the plate cylinder 100. The pressure sensor 120 may also extend over the entire circumference of the plate cylinder 100 or a part of the entire circumference of the plate cylinder 100. In an exemplary embodiment where the pressure sensor 120 extends over the entire length and the entire circumference of the plate cylinder 100, the pressure sensor 120 may perform continuous pressure sensing along the entire length of the nip. When the pressure sensor 120 extends over a part of the entire circumference of the plate cylinder 100, the pressure sensor 120 performs intermittent pressure sensing of the nip. That is, when the plate cylinder 100 rotates, the pressure sensor 120 senses the pressure of the nip when the pressure sensor 120 is positioned at the nip. As the plate cylinder 100 continues to rotate, the pressure sensor 120 moves away from the nip, causing a slight pause in the pressure sensing of the nip. Then, when the rotation of the plate cylinder 100 positions the pressure sensor 120 at the nip again, the pressure sensing of the nip is performed again. In an embodiment where the pressure sensor 120 extends over a part of the entire length of the plate cylinder 100, the pressure sensor 120 senses the pressure along the part of the nip corresponding to its length.

[0022] In an exemplary embodiment where the pressure sensor 120 is on the blanket wheel 110, the pressure sensor 120 may correspond to all or a part of the area of the blanket of the blanket wheel 110. The pressure sensor 120 may be included in all the blankets of the blanket wheel 110 or one or more selected blankets.

[0023] In some embodiments, the pressure sensor 120 may be disposed within or on the back side of the surface of the plate cylinder 100 or the blanket wheel 110. Appropriate pressure sensing devices for sensing pressure can be used for the pressure sensor 120. It will be understood that the pressure sensor 120 may be composed of a plurality of pressure sensing devices, for example, an array of pressure sensing devices extending over the entire area of the pressure sensor 120. Also, in some exemplary embodiments, it will be understood that the pressure sensor 120 may include only a single pressure sensing device.

[0024] FIG. 2 and FIG. 3 are diagrams of the blanket wheel 110 and the mandrel 130 according to an exemplary embodiment of the concept of the present disclosure, in which the pressure sensor 120 is provided to sense the pressure between the blanket wheel 110 and the mandrel 130. For the sake of disclosure economy, the pressure sensor 120 is shown on both the mandrel 130 and the blanket wheel 110. However, it will be understood that without departing from the scope of the concept of the present disclosure, the pressure sensor 120 may be included in only one of the mandrel 130 and the blanket wheel 110.

[0025] Similar to the plate cylinder 100 and the blanket wheel 110, the mandrel 130 and the blanket wheel 110 roll into contact with each other directly or via the can 16 disposed on the mandrel 130. Their contact location may also be referred to as a nip. The pressure sensor 120 is configured to sense the pressure at the nip where the mandrel 130 and the blanket wheel 110 are in contact. Similar to the case of the plate cylinder 100 and the blanket wheel 110, in some exemplary embodiments, the pressure sensor 120 is configured to continuously sense the pressure at the nip between the mandrel 130 and the blanket wheel 110, and in some embodiments, the pressure sensor is configured to intermittently sense the pressure at the nip between the mandrel 130 and the blanket wheel 110.

[0026] In embodiments where the pressure sensor 120 is located on the blanket wheel 110, the pressure sensor 120 may correspond to all or part of the area of ​​the blanket of the blanket wheel 110. The pressure sensor 120 may be included in all of the blankets of the blanket wheel 110, or in one or more selected blankets.

[0027] In embodiments where the pressure sensor 120 is located on the mandrel 130, the pressure sensor 120 may extend along all or part of the length of the mandrel 130, as well as along all or part of the circumference of the mandrel 130. Similar to the pressure sensor 120 on the plate cylinder 100, the pressure sensor 120 on the mandrel 130 may intermittently or continuously sense the pressure between the mandrel 130 and the blanket wheel 110, depending on the extent of the mandrel 130's circumference covered by the pressure sensor 120.

[0028] It will be understood that the pressure sensor 120 may be placed on all of the plate cylinders 100, blanket wheels 110, and mandrels 130, on one of the plate cylinders 100, blanket wheels 110, and mandrels 130, or on any combination of the plate cylinders 100, blanket wheels 110, and mandrels 130, without departing from the scope of the concepts of this disclosure. It will also be understood that the pressure sensor 120 may be placed on a selected plate cylinder 100, multiple plate cylinders 100, or all plate cylinders 100 in the can decorator, without departing from the scope of the concepts of this disclosure. Furthermore, it will be understood that the pressure sensor 120 may be placed on one blanket, multiple blankets, or all blankets of the blanket wheel 110 of the can decorator, without departing from the scope of the concepts of this disclosure. Furthermore, without departing from the scope of the concepts of this disclosure, it will be understood that the pressure sensor 120 may be placed on a selected mandrel 130, multiple mandrels 130, or all mandrels 130 of the can decorator.

[0029] Figure 5 is a schematic diagram of a plate cylinder 100 including a pressure sensor 120, according to an exemplary embodiment of the concept of the present disclosure. The plate cylinder 100 is mounted on a plate cylinder shaft 112. A slip ring 140 is positioned on the plate cylinder shaft 112. The slip ring 140 is connected to the pressure sensor 120 and is operable to receive the sensed pressure output from the pressure sensor 120. The slip ring 140 is also connected to a controller 150 and is configured to provide the controller 150 with the output of the pressure sensor 120 that it has received. The slip ring 140 includes a rotating portion that rotates with the rotation of the plate cylinder 100 and a stationary portion that does not rotate. The rotating portion of the slip ring 140 is configured to receive the output of the pressure sensor 120 and transmit that output to the stationary portion of the slip ring 140. The controller 150 is connected to the stationary portion of the slip ring 140 so that the controller 150 can receive the output of the pressure sensor 120 without having to rotate. In some exemplary embodiments, the controller 150 may be part of a control system for a can decorator.

[0030] It will be understood that the slip ring 140 may also be used in embodiments in which the pressure sensor 120 is located on the blanket wheel 110 or the mandrel 130. For example, if the pressure sensor 120 is located on the blanket wheel 110, the slip ring 140 may be located on the shaft of the blanket wheel 110, and if the pressure sensor is located on the mandrel 130, the slip ring 140 may be located on the shaft of the mandrel 130.

[0031] Figure 6 is a schematic diagram of a plate cylinder 100 including a pressure sensor 120, according to an exemplary embodiment of the concept of the present disclosure. In the exemplary embodiment shown in Figure 6, the pressure sensor 120 is connected to a wireless communication unit 122. The wireless communication unit 122 is configured to receive the output of the pressure sensor 120 and to wirelessly transmit the output of the pressure sensor 120 to a controller 150. It will be understood that in some exemplary embodiments, the wireless communication unit 122 may be integrated with the pressure sensor 120. In some exemplary embodiments, the controller 150 may be part of a control system for the can decorator. It will also be understood that the wireless communication unit 122 may be employed in embodiments in which the pressure sensor 120 is located on a blanket wheel 110 or a mandrel 130.

[0032] In some exemplary embodiments, instead of positioning the pressure sensor 120 within or behind the surface of the plate cylinder 100 or mandrel 130, the pressure sensor 120 may be positioned, for example, on a mounting base of the shaft of the plate cylinder 100 or mandrel 130 relative to the can decorator frame. The force acting on the shaft may be used as a measure of the pressure between the plate cylinder 100 and the blanket wheel 110, or between the mandrel 130 and the blanket wheel 110. In some exemplary embodiments of the concept of this disclosure, the pressure sensor 120 may be positioned directly on the frame of the can decorator to calculate the equivalent force between the plate cylinder 100 and the blanket wheel 110, or between the mandrel 130 and the blanket wheel 110.

[0033] According to various exemplary embodiments of the concept of this disclosure, the pressure sensor 120 senses the pressure between the plate cylinder 100 and the blanket wheel 110, and / or between the mandrel 130 and the blanket wheel 110. Measuring the actual pressure between the plate cylinder 100 and the blanket wheel 110, or between the mandrel 130 and the blanket wheel 110, is more accurate than conventional can decorators where the clearance between these parts was measured. Furthermore, in some exemplary embodiments, the pressure is sensed across the entire contact surface to obtain a more complete pressure sensing. Pressure measured across the entire surface is useful in paralleling and toe-in processes of the plate cylinder and blanket wheel.

[0034] In some exemplary embodiments, the can decorator includes a controller such as the controller 150 shown in Figures 5 and 6. The controller 150 can control various characteristics of the can decorator, including the relative positions between components such as the plate cylinder 100, the blanket wheel 110, and the mandrel 130. The actual pressure between the plate cylinder 100 and the blanket wheel 110, and between the mandrel 130 and the blanket wheel 110, is important for printing high-quality cans. In some exemplary embodiments of the concept of this disclosure, the controller 150 uses the output of a pressure sensor 120 to adjust the relative positions of the plate cylinder 100, the blanket wheel 110, and the mandrel 130 so that a desired pressure between these components can be obtained. For example, the controller 150 may maintain a target pressure between the components and, based on the output of the pressure sensor 120, raise or lower the pressure between the components to the target pressure. In some exemplary embodiments of the concept of this disclosure, automating this process can maintain high print quality and reduce excessive wear on the components of the can decorator.

[0035] While specific embodiments of the present invention have been described in detail, it will be understood by those skilled in the art that, in light of the overall teachings of this disclosure, various modifications and alternatives to those details can be developed. Accordingly, the specific configurations disclosed are for illustrative purposes only and do not limit the scope of the concepts of this disclosure, which should be given the entire scope of the appended claims and all their equivalents.

Claims

1. A blanket wheel having multiple blankets arranged around its outer circumference, A plate cylinder for an inking station, comprising a plate cylinder configured to rotate in contact with the blanket wheel, A mandrel configured to hold the can and to rotate in contact with the blanket wheel, A pressure sensor configured to sense the pressure between the plate cylinder and the blanket wheel, or between the mandrel and the blanket wheel, A can decorator equipped with [features / features].

2. The can decorator according to claim 1, wherein the pressure sensor is located on the plate cylinder and is configured to sense the pressure between the plate cylinder and the blanket wheel.

3. The can decorator according to claim 2, wherein the plate cylinder has an outer peripheral region, and the pressure sensor is configured to sense pressure over the entire outer peripheral region of the plate cylinder.

4. The can decorator according to claim 2, wherein the plate cylinder has an outer peripheral region, and the pressure sensor is configured to sense pressure over a portion of the outer peripheral region of the plate cylinder.

5. The can decorator according to claim 1, wherein the pressure sensor is located on the mandrel and is configured to sense the pressure between the mandrel and the blanket wheel.

6. The can decorator according to claim 5, wherein the mandrel has an outer peripheral region, and the pressure sensor is configured to sense pressure over the entire outer peripheral region of the mandrel.

7. The can decorator according to claim 5, wherein the mandrel has an outer peripheral region, and the pressure sensor is configured to sense pressure over a portion of the outer peripheral region of the mandrel.

8. The can decorator according to claim 1, wherein the pressure sensor is located on at least one blanket of the blanket wheel and is configured to sense the pressure between the plate cylinder and the blanket wheel, and between the mandrel and the blanket wheel.

9. The can decorator according to claim 8, wherein the at least one blanket of the blanket wheel has a surface area, and the pressure sensor is configured to sense pressure across the entire surface area of ​​the at least one blanket.

10. The can decorator according to claim 8, wherein at least one blanket of the blanket wheel has a surface area, and the pressure sensor is configured to sense pressure over a portion of the surface area of ​​the at least one blanket.

11. The can decorator according to claim 1, further comprising a slip ring disposed on a shaft of one of the plate cylinder, the blanket wheel, and the mandrel, wherein the slip ring has a rotating portion connected to the pressure sensor and configured to receive the output of the pressure sensor, and a stationary portion connected to a controller and configured to provide the output of the pressure sensor to the controller.

12. The can decorator according to claim 1, further comprising a wireless communication unit connected to the pressure sensor and configured to receive the output of the pressure sensor, wherein the wireless communication unit is configured to wirelessly send the output of the pressure sensor to a controller.

13. The can decorator according to claim 1, further comprising a controller configured to receive the output of the pressure sensor.

14. The can decorator according to claim 1, wherein the controller is configured to control the relative position of the plate cylinder and the blanket wheel, or the mandrel and the blanket wheel, based on the output of the pressure sensor.

15. The can decorator according to claim 1, wherein the pressure sensor is located on a mounting base of the shaft of the plate cylinder or the shaft of the mandrel.

16. A method for adjusting pressure in a can decorator having a blanket wheel having a plurality of blankets arranged on its outer circumference, a plate cylinder for an inking station configured to rotate in contact with the blanket wheel, and a mandrel configured to hold a can and to rotate in contact with the blanket wheel, A pressure sensor is provided that is configured to sense the pressure between the plate cylinder and the blanket wheel, or between the mandrel and the blanket wheel. To sense a first pressure between the plate cylinder and the blanket wheel, or between the mandrel and the blanket wheel, Determining the target pressure, Adjusting the position of at least one of the plate cylinder, blanket wheel, and mandrel to adjust the first pressure to the target pressure, Methods that include...

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