Stretch wrap machine

Claim 2

A spiral stretch wrap machine comprising means for holding a roll of stretch wrap material in a vertical orientation; a horizontal turntable for supporting a load to be wrapped; means for turning said turntable; means for moving said roll in the vertical direction such that following the securement of the free end of said roll to said load, stretch wrap material is pulled off from said roll and wound in a spiral around said load; and means for automatically applying a continuously increasing brake force to said roll to inhibit the pulling off of stretch wrap material therefrom, said brake force increasing continuously from a minimum value to a maximum value during the initial wrapping of said load and thereafter remaining at said maximum value, said turntable turning through at least one-sixteenth of a turn and at most one complete turn during the time that said brake force is increasing from said minimum value to said maximum value.

Claim 3

A spiral stretch wrap machine in accordance with claim 1 wherein vertical motion of said roll is stopped while said turntable is still turned when the bottom and the top of said load are being wrapped to provide additional wrap reinforcement at the bottom and top of said load, said brake force increasing from said minimum value to said maximum value while vertical motion of said roll is not in progress.

Claim 4

A spiral stretch wrap machine in accordance with claim 1 wherein said maximum brake force is reached before said turntable has made one half of a revolution at the start of a wrapping operation.

Claim 5

A spiral stretch wrap machine in accordance with claim 1 further including manually settable means for indicating whether a support between said turntable and said load is to be wrapped together with the load, and means for controlling the lowest level to which said film roll is moved to selectively wrap said support in accordance with the indication of said manually settable means.

Claim 6

A spiral stretch wrap machine in accordance with claim 1 further including manually settable numerical-value representing means for controlling the vertical level at the bottom of the load below which wrapping does not take place.

Claim 7

A spiral stretch wrap machine in accordance with claim 1 further including manually settable numerical-value representing means for controlling the vertical level at the top of the load above which wrapping does not take place.

Claim 8

A spiral stretch wrap machine in accordance with claim 1 wherein said moving means moves said roll from the bottom of said load to the top, and then back down again.

Claim 9

A spiral stretch wrap machine in accordance with claim 1 further including manually settable means for representing and controlling the bottom and top limits for said moving means.

Claim 10

A spiral stretch wrap machine in accordance with claim 1 further including manually-controlled means for disabling the operation of said moving means while said turntable continues to rotate, thereby allowing selected portions of said load to be wrapped with additional layers of wrap material.

Claim 11

A spiral stretch wrap machine in accordance with claim 1 further including means for manually setting the maximum value of said brake force.

Claim 12

A spiral stretch wrap machine in accordance with claim 1 further including means for adjusting said minimum value of brake force.

Claim 13

A spiral stretch wrap machine in accordance with claim 1 further including means for adjusting the time interval during which said brake force builds up from said minimum value to said maximum value.

Claim 14

A stretch wrap machine comprising means for holding a roll of stretch wrap material in a vertical orientation; a horizontal turntable for supporting a load to be wrapped; means for turning said turntable; and means for automatically applying a continuously increasing brake force to said roll to inhibit the pulling off of stretch wrap material therefrom, said brake force increasing continuously from a minimum value to a maximum value during the initial wrapping of said load and thereafter remaining at said maximum value, said turntable turning through at least one-sixteenth of a turn and at most one complete turn during the time that said brake force is increasing from said minimum value to said maximum value.

Claim 15

A stretch wrap machine comprising means for holding a roll of stretch wrap material in a vertical orientation; a horizontal turntable for supporting a load to be wrapped; means for turning said turntable; and means for automatically applying a continuously increasing brake force to said roll to inhibit the pulling off of stretch wrap material therefrom, said brake force increasing continuously from a minimum value to a maximum value during the initial wrapping of said load and thereafter remaining at said maximum value, said turntable turning through at least one-sixteenth of a turn and at most one complete turn during the time that said brake force is increasing from said minimum value to said maximum value.

Claim 16

A stretch wrap machine in accordance with claim 13 wherein said maximum value brake force is reached after said turntable has made one-sixteenth of a revolution and before it has made one half of a revolution.

Claim 17

A stretch wrap machine in accordance with claim 13 further including means for manually setting the maximum value of said brake force.

Claim 18

A stretch wrap machine in accordance with claim 13 further including means for adjusting said minimum value of brake force.

Claim 19

A stretch wrap machine in accordance with claim 13 further including means for adjusting the time interval during which said brake force builds up from said minimum value to said maximum value.

Claim 20

A stretch wrap machine in accordance with claim 13 wherein said maximum brake force is reached before said turntable has made one half of a revolution at the start of a wrapping operation.

Claim 21

A stretch wrap machine for wrapping a load contained on a skid comprising a turntable for supporting said skid and said load; means for rotating said turntable; a supply of stretch wrap film; means for moving said film in the vertical direction while drawing it from said supply such that after the free end of said film is secured to said load, said film is wrapped around said load in the form of a spiral as said film moves in the vertical direction and said turntable rotates; first manually settable means for representing a numerical value corresponding to the lowest level above said turntable at which wrapping is to take place; second manually settable means for representing a numerical value corresponding to the highest level on said load at which wrapping is to take place; means responsive to said first and second numerical value representing means for limiting movement of said film between said lowest and said highest levels, and means for automatically applying a continuously increasing brake force to said film, said brake force increasing from a minimum value to a maximum value while said turntable turns through at least its first one-sixteenth of a turn and at most its first complete turn.

Claim 22

A stretch wrap machine for wrapping a load contained on a skid comprising a turntable for supporting said skid and said load; means for rotating said turntable; a supply of stretch wrap film; means for moving said film in the vertical direction while drawing it from said supply such that after the free end of said film is secured to said load, said film is wrapped around said load in the form of a spiral as said film moves in the vertical direction and said turntable rotates; first manually settable means for representing a numerical value corresponding to the lowest level above said turntable at which wrapping is to take place; second manually settable means for representing a numerical value corresponding to the highest level on said load at which wrapping is to take place; means responsive to said first and second numerical value representing means for limiting movement of said film between said lowest and said highest levels, and means for automatically applying a continuously increasing brake force to said film, said brake force increasing from a minimum value to a maximum value while said turntable turns through at least its first one-sixteenth of a turn and at most its first complete turn.

Claim 23

A stretch wrap machine in accordance with claim 19 wherein said moving means moves said film in the vertical direction from one of said lowest or highest levels to the other, and then back again.

Claim 24

A stretch wrap machine in accordance with claim 20 further including means for inhibiting the operation of said moving means while said film is at said lowest and said highest levels to provide additional wrap reinforcement at the bottom and top of the load.

Claim 25

A stretch wrap machine in accordance with claim 21 further including third manually settable means for numerically representing and controlling the number of additional wraps formed around said load at the bottom and top thereof.

Claim 26

A stretch wrap machine in accordance with claim 19 wherein said brake force builds up to said maximum value within the first half of a revolution of said turntable and thereafter is maintained at said maximum value.

Claim 27

A stretch wrap machine in accordance with claim 19 further including means for enabling an operator to select the maximum brake force applied to said film.

Claim 28

A stretch wrap machine in accordance with claim 1 wherein said maximum film tension is reached before said turntable has made one complete revolution.