Sheet feeding or delivering – Feeding – With means to align sheet
Reexamination Certificate
2001-04-23
2004-01-13
Walsh, Donald P. (Department: 3653)
Sheet feeding or delivering
Feeding
With means to align sheet
C271S234000, C271S245000, C271S250000
Reexamination Certificate
active
06676124
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention is directed to a device for aligning sheets, having a sheet acceptance region that is limited by two detents arranged at a right angle relative to one another, and having a sheet positioning mechanism that is arranged within the sheet acceptance region lying opposite the corner limited by the two detents, whereby the sheet positioning mechanism comprises at least one paddlewheel that can be rotationally driven around a drive axis that is approximately parallel to the plane of the sheet acceptance region, so that a sheet supplied to the sheet acceptance region is brought into a seated condition with both detents.
2. Description of the Related Art
European Patent Document EP 0 045 657 A1 discloses a copier device having a mechanism for aligning sheets on a masters' plate, whereby the sheets are aligned at two detent edges arranged at a right angle. This mechanism comprises two paddlewheels that are arranged in the corner region of the detent walls. The European reference EP 0 045 657 A1 teaches that each paddlewheel is arranged with an angle of 10° to 25° relative to the neighboring detent edge. As a result thereof, the sheets—in the region of the paddlewheels—are moved at high speed by the respective paddlewheels along the neighboring detent edge to the other detent edge.
The axes of the paddlewheels are connected via a flexible shaft that is driven by a motor. Since both paddlewheels are driven by the common flexible shaft, they are synchronized with one another. The paddles of the two paddlewheels are arranged in anti-phase to one another, so that respectively only one paddlewheel has one of its paddles in contact with a sheet. Having two forces directed in different directions act simultaneously on one sheet is thereby avoided.
Sheets are supposed to be aligned faster at the copier device with this known alignment mechanism than would be manually possible.
The above-cited European Patent Document EP 0 045 657 A1 already discloses an alignment device wherein the paddlewheels are arranged with different conveying directions respectively directed to a detent, whereby this document teaches that the conveying direction of each and every paddlewheel should be arranged with an angle of inclination of 10° through 25° relative to the neighboring detent edge. This means that one of the two paddlewheels has its conveying direction arranged at an angle of 65° through 80° with respect to the sheet delivery direction. Given high delivery speeds, a supplied sheet is therefore placed into a uncontrolled rotational motion that makes a clean alignment of the sheet at the detents impossible.
U.S. Pat. No. 4,589,654 discloses a deposit compartment for the acceptance and stacking of sheets. This deposit compartment is provided with a mechanism for aligning sheets at two detent walls arranged at a right angle using two paddlewheels. One of the two paddlewheels is arranged in the corner region of the detent walls and is aligned obliquely relative to the two detent walls in order to convey the paper sheets against both detent walls. The other paddle wheel is arranged at the detent wall that is arranged at that side lying opposite the principal conveying direction. This paddlewheel is intended to charge the sheets essentially in the principal conveying direction and with a lower force than the first paddlewheel.
Deposit compartments having such a mechanism for aligning sheets can stack sheets with a rate of up to approximately 8 sheets/minute. This stacking rate can be fundamentally influenced by the following parameters:
Sheet delivery speed with which the sheets are supplied to the deposit compartment; the sheet delivery speed especially influences the flight behavior of the sheets after leaving the last conveyor drums. The sheet delivery speed is usually not varied in a specific device; the sheet delivery speeds of different machines, however, can differ.
Spacing with which the sheets are supplied to the deposit compartment, whereby the sheet rate given a constant sheet delivery speed is all the higher the shorter the spacing between two successive sheets is.
Paper type; the paper type is particularly defined by the format, by the basis weight and the surface.
It has been shown that not all paper types can be as neatly stacked given high stacking rates, as a result whereof the stacking quality can be significantly deteriorated. The main reason for this is comprised in the short time available for stacking.
When the stacking rate is to be increased even further beyond the values of 80 sheets/min, then the known mechanisms for aligning sheets are not in the position of neatly stacking different paper types given the desired stacking rate.
U.S. Pat. No. 5,601,283 discloses a device wherein a angle of a sheet positioning mechanism can be modified relative to a conveying direction, being modified with an adjustment mechanism of the sheets to be positioned.
SUMMARY OF THE INVENTION
The present invention is based on an object of providing a device for aligning sheets that can align sheets of different paper types supplied with a high rate (for example, ≧80 sheets/minute) uniformly at two detents, or abutments, arranged at a right angle.
This and other objects are achieved by a device having a device for aligning sheets having a sheet acceptance region that is limited by two detents, or abutments, arranged at a right angle relative to one another, and a sheet positioning mechanism that is arranged within the sheet acceptance region lying opposite the corner limited by the two detents, whereby the sheet positioning mechanism comprises at least one paddlewheel that can be rotationally driven around a drive axis that is approximately parallel to the plane of the sheet acceptance region, so that a sheet supplied to the sheet acceptance region is brought into a seated condition with both detents, whereby the paddlewheel is a double paddlewheel having two individual paddlewheels arranged side-by-side on the drive shaft, and whereby the individual paddlewheels respectively comprise a base member with paddles applied thereto, and the two individual paddlewheels are seated on the drive shaft with play, so that the paddlewheels can turn by an angle relative to one another on the drive shaft.
In a preferred development, the angle lies in the range from ±2° through ±10° and/or in that the two individual paddlewheels are respectively provided with a hole at their base members that is penetrated by a dog pin with play in rotational direction. The sheet positioning mechanism may be adjustable around an axis residing perpendicular to the plane of the acceptance region, so that the conveying direction of the paddlewheel is variable. The axis for the adjustment of the sheet positioning mechanism is a rotational axis proceeding through the center of the paddlewheel, and the drive shaft is seated at an end region of a vertical leg of an L-shaped suspension, whereby the other horizontal leg is arranged above the paddlewheel parallel to the drive shaft. The horizontal leg of the L-shaped suspension is seated at the end region of a paddle lever, being seated rotatable around the rotational axis, whereby the paddle lever has its other end region secured to a mount. Specifically, a driven gear rotatably seated around the rotational axis is provided at the horizontal leg, the rotatory motion thereof being transmitted onto the paddlewheel with a mitre gearing. The driven gear arranged at the suspension is driven by a belt wrapping therearound and around a drive wheel arranged at the mount.
Preferrably, an adjustment mechanism is provided for the adjustment of the conveying direction of the paddlewheel, whereby the adjustment mechanism comprises an adjustment lever that is secured in articulated fashion to an end region of the horizontal leg of the suspension and that is secured to the mount with an adjustment device. The adjustment device is a rotatory lever driven by a stepping motor.
In one embodiment, the axis for the adjustment o
Oce Printing Systems GmbH
Schiff & Hardin & Waite
Shapiro Jeffrey A.
Walsh Donald P.
LandOfFree
Device for aligning sheets does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Device for aligning sheets, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Device for aligning sheets will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-3192911