A method and an apparatus for determining whether a material web is loosely wound around a supply roll are described herein. In addition, a method and an apparatus for tightening the material web around the supply roll are described herein. The present invention is described below in reference to its application in connection with and operation of an apparatus for providing a material web. The web includes a continuous web of printed or non-printed labels coupled in a serial configuration from a supply roll located upon a spindle supported by a support stand to a label applying mechanism. It will be apparent to those skilled in the art and guided by the teachings herein provided that the invention is likewise applicable to any apparatus and/or method for feeding suitable web materials.
Referring now to the figures,
Supply roll spindle 18 is connected to a servo or stepper motor (not shown) with a position feedback device (not shown). The motor and feedback device are connected to motion controller/processor 36. Controller 36 is a device capable of controlling the movement and position of the motor. Controller 36 is programmable. As controller 36 instructs stepper motor (not shown) to rotate supply roll spindle 18 a fixed amount, angular feedback device and encoder (not shown) provides controller 36 with information on the movement of web guide 12.
Rotating 54 spindle 18 in a direction that pulls material web 14 onto supply roll 16 has the effect of applying a force to web guide 12, causing web guide 12 and arm 24 to move from a lower web guide motion limit 34 toward upper web guide motion limit 32. Calculating a threshold web guide displacement 56 consists of configuring controller 36 to calculate a threshold web guide displacement, corresponding to a tightly wound supply roll, within a range of supply roll diameters, for a given supply roll spindle rotation 54. Measuring an actual web guide displacement 58 includes configuring the angular feedback device (not shown), attached to arm 24, to provide controller 36 with an actual displacement of web guide 12.
Test method 50 includes programming controller 36 to compare 60 actual web guide displacement 58 to calculated threshold web guide displacement 56. If actual web guide displacement 58 is equal to or greater than calculated threshold web guide displacement 56, and web guide 12 has moved past a mid-travel position 62 (see
If actual web guide displacement 58 is equal to or greater than calculated threshold web guide displacement 56, and web guide 12 has not moved past a mid-travel position 62 (see
If actual web guide displacement 58 is less than calculated threshold web guide displacement 56, this constitutes a first iteration of a failed test. Controller 36 counts the number of failed tests 66. Controller 36 is provided with a pre-set upper limit of failed test iterations by a user. If the pre-set upper limit of failed test iterations is not reached 68, controller 36 is configured to re-start test method 50. If the pre-set upper limit of failed test iterations is reached 68, controller 36 initiates a correction method 80.
Rotating 84 spindle 18 in a direction that pulls material web 14 onto supply roll 16 has the effect of applying a force to web guide 12, causing web guide 12 and arm 24 to move from lower web guide motion limit 34 toward upper web guide motion limit 32. The angular feedback device (not shown) attached to arm 24 provides controller 36 with data indicating the displacement of web guide 12. Once web guide 12 reaches a position 86 near upper web guide motion limit 32 (see
If web guide 12 has not reached a position 86 near upper web guide motion limit 32, controller 36 continues to count toward a time limit. This time limit is provided to controller 36 by a user. If this time limit is reached 90, controller 36 indicates that supply roll 16 is unsuitable for use and is rejected 92. Setting time limit 90 prevents the labeling machine from being indefinitely tied up in test method 50 and correction method 80.
In one embodiment, a computer program is provided to controller 36. The program is embodied on a computer readable medium and utilizes a Structured Query Language (SQL) with a client user interface front-end for administration and a web interface for standard user input and reports. In an example embodiment, the system is web enabled and is run on a business-entity intranet. In another embodiment, the system is fully accessed by individuals having an authorized access outside the firewall of the business-entity through the Internet. In a further example embodiment, the system is run in a Windows® NT environment (Windows is a registered trademark of Microsoft Corporation, Redmond, Wash.). The application is flexible and designed to run in various different environments without compromising any major functionality.
The systems and processes are not limited to the specific embodiments described herein. In addition, components of each system and each process can be practiced independent and separate from other components and processes described herein. Each component and process also can be used in combination with other assembly packages and processes.
The computer program embodied on a computer readable medium for testing and correcting supply roll 16 prompts a user to initiate test method 50. The computer program includes computer code that corresponds to the steps of test method 50 including, providing the motor with a direction and amount in which to rotate 54, calculating a threshold web guide movement corresponding to the provided motor rotation 56, comparing the calculated threshold web guide movement to an actual web guide movement 60 provided to the computer program by an encoder 58, monitoring the actual displacement of the web guide 62, counting iterations of fixed supply roll rotations 68, and either beginning a normal label applying machine setup procedure 64, or prompting a start of correction method 80 if material web 14 is determined to be too loosely wound around supply roll 16.
The computer program embodied on a computer readable medium for testing and correcting supply roll 16 also includes computer code that corresponds to the steps of correction method 80. These steps include instructing the motor to continuously rotate the spindle 84, monitoring the web guide movement 86, and maintaining a count 90 of the length of correction method 80. The computer program is provided with an upper time limit for correction by a user. The computer program reverts back to the computer code corresponding to test method 50 when web guide 12 reaches an upper limit of web guide movement. The computer program provides a user with an indication that supply roll 16 is rejected 92 if the upper time limit for correction passes prior to web guide 12 reaching an upper limit of web guide movement 86.
While the invention has been described in terms of various specific embodiments, those skilled in the art will recognize that the invention can be practiced with modification within the spirit and scope of the claims.