Stretch wrap monitoring device

1. A stretch wrapping machine for wrapping a stretch wrap film around a load, the machine comprising:

a dispenser mechanism supporting a roll of stretch wrap film and including a pre-stretch roller assembly for receiving the film from the roll and guiding the film to the load to be wrapped around the load supported thereon;

a first sensor associated with the roll and configured to generate a first signal as the film travels from the roll to the pre-stretch roller assembly, wherein the first sensor is a time-of-flight sensor for measuring the distance between the first sensor and the film on the roll;

a second sensor associated with the load and configured to generate a second signal as the film is wrapped around the load; and

a processor configured and operable to;

receive said first signal and calculate a pre-stretch length of the film based on said first signal during a time interval;

receive said second signal and calculate a stretched length of the film as the film is wrapped around the load during the time interval,

calculate a percentage of stretch of the film based on said pre-stretch length and said stretched length; and

generate a sensible output based on the calculated percentage of stretch,

wherein the processor is configured and operable to determine a radius of the film on the roll and to calculate the pre-stretch length of the film based on the radius.

2. The stretch wrapping machine of claim 1 , wherein:

the time-of-flight sensor emits a signal or beam directed toward the film on the roll;

the film on the roll has absorption properties for the signal or beam emitted by the sensor; and

the processor is further configured and operable to determine a corrected distance between the first sensor and the film on the roll to correct for absorption properties of the film on the roll.

3. A stretch wrapping machine for wrapping a stretch wrap film around a load, the machine comprising:

a dispenser mechanism supporting a roll of stretch wrap film and including a pre-stretch roller assembly for receiving the film from the roll and guiding the film to the load to be wrapped around the load supported thereon;

a first sensor associated with the roll and configured to generate a first signal as the film travels from the roll to the pre-stretch roller assembly;

a second sensor associated with the load and configured to generate a second signal as the film is wrapped around the load, wherein the second sensor is a distance sensor and said second signal is indicative of the distance between said second sensor and the load; and

a processor configured and operable to;

receive said first signal and calculate a pre-stretch length of the film based on said first signal during a time interval;

receive said second signal and calculate a stretched length of the film as the film is wrapped around the load during the time interval,

calculate a percentage of stretch of the film based on said pre-stretch length and said stretched length; and

generate a sensible output based on the calculated percentage of stretch,

wherein the processor is configured and operable to calculate a length of the film wrapped around the load in the time interval, wherein the length corresponds to the stretched length.

4. A system associated with a stretch wrapping machine for monitoring the percentage stretch of a stretch wrap film as it is wrapped around a load by the stretch wrapping machine, the stretch wrapping machine including a dispenser mechanism supporting a roll of stretch wrap film and including a pre-stretch roller assembly for receiving the film from the roll and guiding the film to the load to be wrapped around the load, said system comprising:

a first sensor associated with the roll and configured to generate a first signal as the film travels from the roll to the pre-stretch roller assembly, wherein the first sensor is a time-of-flight sensor for measuring the distance between the first sensor and the film on the roll;

a second sensor associated with the load and configured to generate a second signal as the film is wrapped around the load; and

a controller including a processor configured and operable to;

receive said first signal and calculate a pre-stretch length of the film based on said first signal during a time interval;

receive said second signal and calculate a stretched length of the film as the film is wrapped around the load during the time interval,

calculate a percentage of stretch of the film based on said pre-stretch length and said stretched length; and

generate a sensible output based on the calculated percentage of stretch,

wherein the processor is configured and operable to determine a radius of the film on the roll and to calculate the pre-stretch length of the film based on the radius.

5. The system of claim 4 wherein:

the time-of-flight sensor emits a signal or beam directed toward the film on the roll;

the film on the roll has absorption properties for the signal or beam emitted by the sensor; and

the processor is further configured and operable to determine a corrected distance between the first sensor and the film on the roll to correct for absorption properties of the film on the roll.

6. A system associated with a stretch wrapping machine for monitoring the percentage stretch of a stretch wrap film as it is wrapped around a load by the stretch wrapping machine, the stretch wrapping machine including a dispenser mechanism supporting a roll of stretch wrap film and including a pre-stretch roller assembly for receiving the film from the roll and guiding the film to the load to be wrapped around the load, said system comprising:

a first sensor associated with the roll and configured to generate a first signal as the film travels from the roll to the pre-stretch roller assembly;

a second sensor associated with the load and configured to generate a second signal as the film is wrapped around the load, wherein the second sensor is a distance sensor and said second signal is indicative of the distance between said second sensor and the load; and

a controller including a processor configured and operable to;

receive said first signal and calculate a pre-stretch length of the film based on said first signal during a time interval;

receive said second signal and calculate a stretched length of the film as the film is wrapped around the load during the time interval,

calculate a percentage of stretch of the film based on said pre-stretch length and said stretched length; and

generate a sensible output based on the calculated percentage of stretch,

wherein the processor is configured and operable to calculate a length of the film wrapped around the load in the time interval, the length corresponding to said stretched length.