Patent Application
20070145062
The invention relates to an apparatus for dispensing absorbent material from a roll of absorbent material such as paper towels, toilet paper or other wiping materials.
In conventional sheet dispensing apparatus, a supply roll of absorbent material is incrementally dispensed through a dispensing opening in a housing. Sheets pass from the supply roll, while still connected to the roll, and wind around a tensioning device and a drum. The drum may contain a cutting or perforating device or a cutting device may be at the dispensing opening to separate the sheets from the roll upon dispensing.
A problem with conventional devices is that when the sheets are dispensed from the supply roll, the force required to pull the sheets around the tensioning device and separate the sheets from the supply roll, causes the supply roll to over rotate. This over rotation in turn causes excess sheet material still attached to the supply roll to be unrolled from the supply roll and remain within the housing. The unrolled and as yet undispensed sheet material tends to jam the tensioning device and/or the drum, so that the dispensing device must be serviced to remove the jam.
U.S. Pat. No. 6,196,102 to Granger has attempted to solve the above-noted problem by including a component that is continuously in contact with the supply roll, and relates the motion of the roll to that of the drum or tensioning device. The device of Granger is a roller on the end of a lever. The roller contacts the supply roll and is driven by a drive belt connected to the drum or tensioning device. The roller of Granger is designed to help control the unwinding of the supply roll.
However, the contact between the roller of Granger and the supply roll is essentially a point-to-point contact that thus poorly compensates for irregularities in the supply roll such as “out of roundness”, wrinkles and uneven surfaces.
An object of the invention is to overcome the shortcomings of the prior art, or to alleviate the shortcomings of the prior art at least in part.
Another object of the invention is to have a supply roll contact device that better compensates for irregularities on the supply roll.
Yet another object of the preferred embodiments of the invention is to decrease the contact force required to drive the supply roll.
The above and other objects and advantages of the invention will become apparent from the following detailed description of preferred embodiments thereof, given with reference to the accompanying drawing figures, wherein:
The present invention departs from the device described in U.S. Pat. No. 6,196,102, the entirety of which patent is hereby expressly incorporated by reference.
Within the housing 2 there is a drum 4 around which a roll of absorbent material R is partially wound when the dispenser is in use. The drum 4 may include a cutting device 5 that rotates with the drum 4 and that extends from a slot (see
A preferred embodiment of the cutting device 5 is described in co-pending U.S. patent application Ser. No. 10/812,183, the entirety of which is hereby incorporated by reference.
To provide tension to the roll of absorbent material R, a tensioning device 6 is provided. A web from the roll of material R is first partially wound around the tensioning device 6 and then is partially wound around the drum 4.
The roll of material R may be held upon a roll receiver 9, which in turn may be supported by a pair of roll support arms 20, 22. The roll support arms 20, 22 may be located in an upper part of housing 2 as seen in
In operation, as seen in
The web unwinds from the drum 4 in the direction C and then exits the housing 2 from a dispensing opening (not numbered). The dispensing opening may have a follow-on roller 10 therein as seen in
As shown in
The lever works in opposition to an elastic element, which is shown as spring 13, although other elements that apply tension to the lever are also contemplated. The spring 13 places the lever in tension generally in a direction D as seen in
At an upper end 12c of leg 12d, a pair of pulleys 15, 16 are connected. Pulley 15 is preferably freely rotatable about shaft 14 and pulley 16 is preferably freely rotatable about shaft 24. A supply roll drive belt 18 is wrapped around the pulleys 15, 16 and rotates with the pulleys 15, 16. The supply roll drive belt continuously contacts the roll of absorbent material R with a force F and assists in rotating the roll of absorbent material R. Supply roll drive belt 18 may be a flat belt or may instead be a flexible annular ring in the nature of an 0-ring, that travels around pulleys 15, 16.
In a presently-preferred embodiment as seen in
The roll of material R is urged in rotation not only by tension applied to the web of absorbent material that extends from the dispensing opening, but also by the rotation of the supply roll drive belt 18. This is due to supply roll drive belt 18 being driven in direction E by rotation of the drum 4. Alternatively, the supply roll drive belt 18 may be driven using the tensioning device.
In a first embodiment, as seen in
Conversely, the belt 18 also exerts a braking effect on the roll of absorbent material as the drum decelerates during the end of a dispensing cycle, thereby to inhibit the undesired over rotation phenomenon described above, and this more reliably than with the structure provided in U.S. Pat. No. 6,196,102.
The supply roll drive belt 18 may be flat to maximize the contact patch between the supply roll drive belt 18 and the roll of material R, or may be annular, as noted above. In addition, having the supply roll drive belt 18 extending between two or more pulleys also creates a large contact patch between the supply roll drive belt 18 and the roll of absorbent material R. A large contact patch is advantageous to provide flexibility and to be able to conform to any irregularities that may be present in the roll.
In the embodiment of
As set forth above, the web of material could unroll in a counter-clockwise direction as shown by the dotted lines in
In a presently-preferred embodiment of the present invention, the shaft on which the drum 4 rotates includes a one-way bearing enabling the drum 4 to rotate only in one direction, upon activation of the actuating device. In the embodiment of
The invention has been described in detail with respect to the preferred embodiments. However, it will be apparent to those of skill in the art that changes or modifications may be made without departing from the true spirit of the invention. The invention should not be limited by these embodiments and should be defined by the appended claims.
