FIELD OF THE INVENTION
The present invention concerns stretch wrapping machines, and more particularly relates to a carriage for a stretch wrapping machine.
BACKGROUND OF THE INVENTION
During the past several decades, considerable developments have been made in the field of wrapping a load with a stretched web of film. Most notably, the film web dispenser used in stretch wrapping operations has developed to the extent that it contains a series of rollers which defines a path through which the web passes so that it can be prestretched prior to being dispensed on the load.
Such stretch wrapping apparatus performs admirably in accomplishing its intended goal of wrapping a load with a stretched web of film. However, the procedure of threading the film web through the series of rollers in the film web dispenser prior to operation of the stretch wrapping apparatus has been found to be time consuming and difficult. This is especially true now because of the development of film web dispensers having increased numbers of rollers and also because such rollers are often closely spaced and difficult to turn because of their effective interconnection for prestretching the film web prior to dispensing the film web on the load.
SUMMARY OF THE INVENTION
An aspect of the present invention is to provide a stretch wrap assembly comprising a base, a turntable mounted on the base, a column extending upwardly from the base, and a carriage vertically movable upon the column, with the carriage having a housing configured to have stretch wrap move therethrough for wrapping a product on the turntable. The housing includes a plurality of rollers extending between a bottom of the housing and a top of the housing. The plurality of rollers rotate about roller axes. A wrap surface of the stretch wrap engages exterior surfaces of the rollers as the stretch wrap moves therethrough. The housing has a threading assembly for moving a front end of the stretch wrap through the housing during initiation of installation of the stretch wrap through the housing. The threading assembly includes a manually movable system moving the front end of the stretch wrap. The manually movable system comprises an endless link moving about a plurality of rotating members. The rotating members rotate about thread axes. The endless link is configured to be engaged with the front end of the stretch wrap to move the stretch wrap through the housing. The roller axes and the thread axes are parallel and spaced from each other such that none of the roller axes are collinear with the thread axes.
Another aspect of the present invention is to provide a stretch wrap assembly comprising a base, a turntable mounted on the base, a column extending upwardly from the base, and a carriage vertically movable upon the column, with the carriage having a housing configured to have stretch wrap move therethrough for wrapping a product on the turntable. The housing includes a plurality of rollers extending between a bottom of the housing and a top of the housing. The plurality of rollers rotate about roller axes. A wrap surface of the stretch wrap engages exterior surfaces of the rollers as the stretch wrap moves therethrough. The housing has a threading assembly for moving a front end of the stretch wrap through the housing during initiation of installation of the stretch wrap through the housing. The threading assembly includes a manually movable system moving the front end of the stretch wrap. The manually movable system comprises an endless link moving about a plurality of rotating members. The rotating members rotate about thread axes. The endless link is configured to be engaged with the front end of the stretch wrap to move the stretch wrap through the housing. The endless link is located on a bottom surface of the top of the housing. The threading system includes a handle extending through the top of the housing for manually moving the endless link to move the front end of the stretch wrap through the housing.
Yet another aspect of the present invention is to provide a carriage for a stretch wrap assembly comprising a housing configured to have stretch wrap move therethrough for wrapping a product on the turntable. The housing includes a plurality of rollers extending between a bottom of the housing and a top of the housing. The plurality of rollers rotate about roller axes. A wrap surface of the stretch wrap engages exterior surfaces of the rollers as the stretch wrap moves therethrough. The housing has a threading assembly for moving a front end of the stretch wrap through the housing during initiation of installation of the stretch wrap through the housing. The threading assembly includes a manually movable system moving a front end of the stretch wrap. The manually movable system comprises an endless link moving about a plurality of rotating members. The rotating members rotate about thread axes. The endless link is configured to be engaged with the front end of the stretch wrap to move the stretch wrap through the housing. The endless link is located at a bottom surface of the top of the housing. The threading system includes a handle extending through the top of the housing for manually moving the endless link to move the front end of the stretch wrap through the housing. The roller axes and the thread axes are parallel and spaced from each other such that none of the roller axes are collinear with the thread axes.
Another aspect of the present invention is to provide a method of feeding stretch wrap through a carriage of a stretch wrap machine comprising providing a housing having a plurality of rollers extending between a bottom of the housing and a top of the housing, with the plurality of rollers rotating about roller axes, providing the housing with a threading assembly for moving a front end of the stretch wrap through the housing during initiation of installation of the stretch wrap through the housing, providing the threading assembly with a manually movable system comprising an endless link and a plurality of rotating members, extending a handle of the threading system through the top of the housing, locating the endless link at a bottom surface of the top of the housing, providing the rollers with roller axes, engaging a front end of the stretch wrap with the endless link, moving the front end of the stretch wrap through the housing by moving the handle, with the rotating members rotating about thread axes during movement of the handle, and moving the front end of the stretch wrap through the housing includes moving the endless link about the rotating members. The roller axes and the thread axes are parallel and spaced from each other such that none of the roller axes are collinear with the thread axes.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a perspective view of a wrap machine of the present invention.
FIG. 2 is a schematic view of a carriage of the wrap machine of the present invention in a loaded (threaded) and ready to wrap position.
FIG. 3 is a schematic view of a sprockets and rollers assembly of the carriage of the wrap machine of the present invention.
FIG. 4A is a schematic view of the carriage of the wrap machine of the present invention in a loading position.
FIG. 4A′ is a partial front view of the carriage of the wrap machine of the present invention in a first threading position.
FIG. 4B is a schematic view of the carriage of the wrap machine of the present invention in a second threading position.
FIG. 4C is a schematic view of the carriage of the wrap machine of the present invention in a third threading position.
FIG. 4D is a schematic view of the carriage of the wrap machine of the present invention in a fourth threading position.
FIG. 4E is a schematic view of the carriage of the wrap machine of the present invention in a fifth threading position.
FIG. 4F is a schematic view of the carriage of the wrap machine of the present invention in a sixth threading position.
FIG. 4G is a schematic view of the carriage of the wrap machine of the present invention in a seventh threading position.
FIG. 4H is a schematic view of the carriage of the wrap machine of the present invention a fully threaded position.
FIG. 5 is a partial side view of the carriage of the wrap machine of the present invention in the loading position.
FIG. 6 is a partial top view of the carriage of the wrap machine of the present invention.
FIG. 7 is a top view of a door assembly of the carriage of the present invention.
FIG. 8 is a partial front view of the carriage of the present invention, illustrating only a portion of the top of the carriage and a portion of an endless link of a manual threading system.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
For purposes of description herein, the terms “upper,” “lower,” “right,” “left,” “rear,” “front,” “vertical,” “horizontal,” and derivatives thereof shall relate to the invention as orientated in FIG. 1. However, it is to be understood that the invention may assume various alternative orientations, except where expressly specified to the contrary. It is also to be understood that the specific devices and processes illustrated in the attached drawings, and described in the following specification are simply exemplary embodiments of the inventive concepts. Hence, specific dimensions and other physical characteristics relating to the embodiments disclosed herein are not to be considered as limiting.
The reference number 10 (FIG. 1) generally designates a wrap machine of the present invention. The wrap machine 10 includes a base 12 having a turntable 14 mounted thereon. The wrap machine 10 further includes a column 16 having a vertically movable carriage 18 (shown schematically) located thereon. Stretch wrap 20 moves with the carriage 18. The stretch wrap 20 wraps a package 24 mounted on the turntable 14 and rotating therewith. Although not shown, the wrap machine 10 may also include a gripping and cutting device for gripping the stretch wrap 20 and cutting the stretch wrap 20 during certain portions of the process of wrapping the stretch wrap 20 about the package 24. Such gripping and cutting devices are well known to those skilled in the art.
In the illustrated example, the carriage 18 is used to prestretch the stretch wrap 20. FIG. 2 illustrates schematically prestretching components of the carriage 18 of the present invention. As illustrated in FIG. 2, the carriage 18 includes a source of the stretch wrap 20 in the form of a roll 22 of stretch wrap 20, a first guide roller 23, a second guide roller 27, a first nip roller 25, a first pre-stretch roller 26, an idler roller 28, a second pre-stretch roller 30, a second nip roller 32 and a dancer roller 34. The stretch wrap 20 travels through the carriage 18 from the roll 22 of stretch wrap 20, around a portion of the circumference of the first guide roller 23, around a portion of the circumference of the second guide roller 27, around a portion of the circumference of the first nip roller 25, around a portion of the circumference of the first pre-stretch roller 26, around a portion of the circumference of the idler roller 28, around a portion of the circumference of the second pre-stretch roller 30, around a portion of the circumference of the second nip roller 32, around a portion of the circumference of the dancer roller 34, and to the package 24. The first pre-stretch roller 26 and the second pre-stretch roller 30 are driven (rotated) at different speeds and/or have a different circumference in order to stretch the stretch wrap 20 as it passes by the first pre-stretch roller 26 and the second pre-stretch roller 30 (as is well known to those skilled in the art). The idler roller 28 rotates freely and is positioned to maintain the stretch wrap 20 against the first pre-stretch roller 26 and the second pre-stretch roller 30. The first nip roller 25 is configured to maintain the stretch wrap 20 against the first pre-stretch roller 26 as the stretch wrap 20 is stretched by the first pre-stretch roller 26. The first nip roller 25 is allowed to move towards and away from the first pre-stretch roller 26 as discussed in more detail below. Likewise, the second nip roller 32 is configured to maintain the stretch wrap 20 against the second pre-stretch roller 30 as the stretch wrap 20 is stretched by the second pre-stretch roller 30.
An aspect of the present invention provides for a manual threading system 50 for threading the stretch wrap 20 through the carriage 18 and around the rollers. The manual threading system 50 includes a rotating handle 52, an endless link 54 having a hook 56 and a plurality of rotary members 58 supporting the endless link 54 at a plurality of locations. In the illustrated embodiment, the endless link 54 is a chain and the rotary members 58 are sprockets. However, it is contemplated that other endless links and rotary members could be used. As illustrated in FIGS. 1, 5 and 8, the rotating handle 52 extends upward out of a top 60 of the carriage 18 and the endless link 54 and the rotary members 58 extend downward from the top 60 of the carriage 18.
In the illustrated embodiment, the manual threading system 50 uses the rotary members 58 to thread the stretch wrap 20 through the carriage 18. In the illustrated example as shown in FIG. 3, the manual threading system 50 includes a drive sprocket 62, a first driven sprocket 64, a second driven sprocket 66 and a third driven sprocket 68. As discussed in more detail below, the drive sprocket 62 is rotated by manual rotation of the rotating handle 52. As the drive sprocket 62 rotates, the drive sprocket 62 moves the endless link 54 and the hook 56 about the first driven sprocket 64, the second driven sprocket 66 and the third driven sprocket 68. FIG. 3 illustrates the relative location of the drive sprocket 62, the endless link 54, the first driven sprocket 64, the second driven sprocket 66 and the third driven sprocket 68 relative to the first nip roller 25, the first pre-stretch roller 26, the idler roller 28, the second pre-stretch roller 30, and the second nip roller 32. However, the position of the rotatory members 58 can be altered if the locations of the first nip roller 25, the first pre-stretch roller 26, the idler roller 28, the second pre-stretch roller 30, and the second nip roller 32 are altered.
FIGS. 4A-4G illustrate the steps for threading the stretch wrap 20 through the carriage 18 using the manual threading system 50. As illustrated in FIGS. 4A and 4A′, threading of the carriage 18 begins with pulling a front end 70 of the stretch wrap 20 off of the roll 22 of stretch wrap 20 and in front of the first guide roller 23 and the second guide roller 27. The front end 70 of the stretch wrap 20 is then wrapped around the first nip roller 25 and bunched up into a ball 71 at a top edge 72 of the stretch wrap 20. As shown in FIG. 4A and as discussed in more detail below, the first nip roller 25 can be moved away from the first pre-stretch roller 26 along line 74 into a load position to allow the stretch wrap 20 to be easily and manually wrapped around the first nip roller 25.
Once the stretch wrap 20 is pulled about the first nip roller 25 as illustrated in FIG. 4A, the ball 71 at the front end 70 of the stretch wrap 20 is placed within the hook 56 of the manual threading system 50. As illustrated in FIG. 4B, the ball 71 is located adjacent a front edge of the first pre-stretch roller 26 before the rotating handle 52 of the manual threading system 50 is rotated. It is noted that, except for the first nip roller 25, the stretch wrap 20 is wrapped about axles of the rollers, at a location above the rollers. This allows the stretch wrap 20 to be threaded through the carriage 18 without powering the carriage 18 to turn the pre-stretch rollers. However, it is contemplated that the carriage 18 could be powered and the stretch wrap 20 could be threaded about the rollers, with the power to the system moving the pre-stretch rollers during the threading (either with the first nip roller 25 moved back along line 74 to a home position or with the first nip roller 25 moved with a door to an open position). As the rotating handle 52 of the manual threading system 50 is rotated, the drive sprocket 62 begins rotating. As the drive sprocket 62 begins rotating, the endless link 54 starts moving about the drive sprocket 62 and the first driven sprocket 64. Since the first driven sprocket 64 is located outside an axle 200 of the first pre-stretch roller 26, the hook 56 carrying the ball 71 at the front end 70 of the stretch wrap 20 will carry the stretch wrap 20 about axle 200 of the first pre-stretch roller 26, thereby pulling the stretch wrap 20 off of the roll 22, about the first guide roller 23, about the first nip roller 25, and about the axle 200 of the first pre-stretch roller 26 as illustrated in FIG. 4C.
As the rotating handle 52 continues to be rotated, the endless link 54 will pull the hook 56 with the ball 71 at the front end 70 of the stretch wrap 20 towards the second driven sprocket 66. As illustrated in FIG. 3, the endless link 54 wraps about an inside of the second driven sprocket 66. Therefore, the hook 56 with the ball 71 at the front end 70 of the stretch wrap 20 will pull the stretch wrap 20 about an outside of the axle 200 of the first pre-stretch roller 26 and an inside of an axle 300 of the idler roller 28 as illustrated in FIG. 4D. Continuing rotation of the rotating handle 52 causes the endless link 54 will pull the hook 56 with the ball 71 at the front end 70 of the stretch wrap 20 towards the third driven sprocket 68. As illustrated in FIG. 3, the endless link 54 wraps about an outside of the third driven sprocket 68. Therefore, the hook 56 with the ball 71 at the front end 70 of the stretch wrap 20 will pull the stretch wrap 20 along an inside of the axle 300 of the idler roller 28 and toward and around the axle 400 of the second pre-stretch roller 30 as illustrated in FIG. 4E. Further rotation of the rotating handle 52 causes the endless link 54 to pull the hook 56 with the ball 71 at the front end 70 of the stretch wrap 20 back towards the drive sprocket 62. As illustrated in FIG. 3, the endless link 54 wraps about an outside of the drive sprocket 62. Therefore, the hook 56 with the ball 71 at the front end 70 of the stretch wrap 20 will pull the stretch wrap 20 about the axle 400 of the second pre-stretch roller 30 and along an inside of an axle 500 of the second nip roller 32 as illustrated in FIG. 4F and thereafter toward an axle 600 of the dancer roller 34 as illustrated in FIG. 4G. At this point, the ball 71 at the front end 70 of the stretch wrap 20 is removed from the hook 56 and then pulled around the axle 600 of the dancer roller 34 and towards the package 24 for wrapping about the package 24 as illustrated in FIG. 4H. At this point, the first nip roller 25 can be moved back along line 74 to the position shown in FIG. 2. As discussed in more detail below, the wrap about the axles of the rollers will move downward over the rollers during use of the machine (or before use of the machine one the pre-stretch rollers are powered) to position the stretch wrap 20 about the rollers as illustrated in FIG. 2.
FIGS. 5-8 illustrate various aspects of an embodiment of the carriage 18 of the wrap machine 10 of the present invention. FIG. 5 is a side view of the carriage 18, with the first guide roller 23, the second guide rollers 27, the second nip roller 32, the idler roller 28, the roll 22 of stretch wrap 20 and the dancer roller 34 removed for clarity. In the illustrated example, the carriage 18 includes a bottom 80, a rear wall 82 having a rail 84 extending rearwardly therefrom for insertion into a track in the column 16 for vertically moving the carriage 18 on the column 16 as well known to those skilled in the art, the top 60 and a pivoting front door 86. The first-pre-stretch roller 26 and the second pre-stretch roller 30 include roller axles 88 that extend into the top 60 and the bottom 80 of the carriage 18. The first-pre-stretch roller 26 and the second pre-stretch roller 30 pivot about the roller axles 88. While not shown, the first guide roller 23, the second guide roller 27, the second nip roller 32 and the idler roller 28 also include roller axles 88 that extend into the top 60 and the bottom 80 of the carriage 18. As is well known to those skilled in the art, the dancer roller 34 is connected to top and bottom links (shown schematically as links 92 in FIG. 2) that allow the dancer roller 34 to pivot about a vertical axis 94 located at an end of the links opposite to the dancer roller 34.
In the illustrated example, the manual threading system 50 is connected to the top 60 of the carriage 18. As illustrated in FIGS. 5 and 8, the first driven sprocket 64, the second driven sprocket 66 and the third driven sprocket 68 each include sprocket axles 96 connected to a center thereof and extending into the top 60 of the carriage 18 for allowing the first driven sprocket 64, the second driven sprocket 66 and the third driven sprocket 68 to rotate. A drive link 98 extends through the top 60 of the carriage 18 and connects the rotating handle 52 to the drive sprocket 62 such that rotation of the rotating handle 52 rotates the drive sprocket 62.
The illustrated first nip roller 25 is connected to the pivoting front door 86 to allow the first nip roller 25 to move along the line 74. The pivoting front door 86 includes a front plate 100 pivotally attached at a bottom horizontal pivot joint 102 to a front of the bottom 80 of the carriage 18. The front plate 100 includes a handle 104 extending from a front face thereof for easily moving the pivoting front door 86 from a loading position wherein the pivoting front door 86 is fully rotated outward to a threading position wherein the pivoting front door 86 is in a closed and upright position. As discussed above, the stretch wrap 20 is pulled from the roll 22 and pulled about the first nip roller 25 when the pivoting front door 86 is in the loading position. Furthermore, the ball 71 of the stretch wrap 20 is connected to the hook 56 of the manual threading system 50 and the manual threading system 50 is actuated to thread the stretch wrap 20 about the axles of the rollers before the pivoting front door 86 is pivoted to the closed and upright position. The front plate 100 of the pivoting front door 86 can have a locking mechanism 106 for locking the pivoting front door 86 in the closed and upright position. The locking mechanism 106 is configured to engage a mating portion on the top 60 of the carriage 18. The locking mechanism 106 can be a T-shaped knob that extending through an opening and then turned to prevent the T-shaped knob from exiting the opening, a biased turning mechanism including a knob with a pair of plates configured to extend through or into slots, with a biasing member preventing the knob from turning or any other locking mechanism 106.
In the illustrated example, the first nip roller 25 is connected to a C-shaped roller holder 108 extending rearward from a rear face of the front plate 100 of the pivoting front door 86. The C-shaped roller holder 108 includes a top panel 110, a bottom panel 112 and a side panel 114. The axle 90 of the first nip roller 25 extends through slots 91 in the top panel 110 and the bottom panel 112. The slots 91 allow the axle 90 of the first nip roller 25 to move laterally to allow the axle 90 and the first nip roller 25 to move towards and away from the first pre-stretch roller 26 as the pivoting front door 86 is opened and closed. Once the carriage is threaded, the stretch wrap 20 will pull the first nip roller 25 towards the first pre-stretch roller 26. However, it is contemplated that the first nip roller 25 could be spring biased toward the first pre-stretch roller 26 (to the left in FIG. 6). The side panel 114 is opposite the first pre-stretch roller 26 when the pivoting front door 86 is in the closed and upright position as illustrated in FIG. 6. The side panel 114 includes a bent extension lip 116 that extends between the first nip roller 25 and the second nip roller 32 when the pivoting front door 86 is in the closed and upright position as illustrated in FIG. 6. The bent extension lip 116 prevents the stretch wrap 20 surrounding the first nip roller 25 from engaging the stretch wrap 20 leaving the second nip roller 32, thereby preventing jamming of the stretch wrap 20 within the carriage 18.
It is contemplated that axle the first guide roller 23, the axle of the second guide roller 27, the axle of the first nip roller 25, the axle 200 of the first pre-stretch roller 26, the axle 300 of the idler roller 28, the axle 400 of the second pre-stretch roller 30, the axle 500 of the second nip roller 32 and the axle 600 of the dancer roller 34 could have conical tops 200 for allowing the stretch wrap 20 to easily move down the axles of the rollers and the rollers as the stretch wrap 20 is threaded through the carriage 18. FIG. 5 illustrates the first pre-stretch roller 26 and the second pre-stretch roller 30 having the conical tops 200, but it is contemplated that any of the rollers could have the conical tops 200. As illustrated in FIG. 5, the conical tops 200 have a smaller end at a top thereof and the larger end has the same (or similar) circumference as the pre-stretch roller connected thereto. However, it is contemplated that the conical tops 200 could have a smaller end at the bottom thereof, with the smaller end still having the same (or similar) circumference as the pre-stretch roller connected thereto.
The above description is considered that of the one embodiment only. Modification of the invention will occur to those skilled in the art and to those who make or use the invention. Therefore, it is understood that the embodiment shown in the drawings and described above is merely for illustrative purposes and not intended to limit the scope of the invention.
Patent Application
20130227919
