FEEDER MECHANISM WITH ADJUSTABLE PICKUP HEADS
In a sheet feeder apparatus, a feeder mechanism for picking up sheets from a stack of sheets of a material includes a support bar, at least one pickup head, and an adjuster. The support bar includes cylindrical ends and an intermediate portion between the cylindrical ends. The cylindrical ends are configured to pivotally couple to control arms of the sheet feeder apparatus. The pickup heads are coupled to the intermediate portion of the support bar and an adjuster is coupled to the support bar at one of the cylindrical ends. The adjuster includes a bracket coupled to the intermediate portion of the support bar, a pivot arm selectively pivotable about the cylindrical end of the support bar, and an adjustment mechanism coupled between the bracket and the pivot arm. The adjustment mechanism pivots the support bar relative to the pivot arm to thereby tilt the pickup heads.
The present invention relates generally to a sheet feeder apparatus. More specifically, the present invention relates to a feeder mechanism for a sheet feeder apparatus having adjustable pickup heads.
BACKGROUND OF THE INVENTIONA sheet feeder apparatus is a device that holds a stack of paper, cardstock, and the like, and feeds each sheet into a printer, printing press, or similar device one sheet at a time. In a sheet feeder apparatus, a feeder mechanism is typically implemented to lift a single sheet of material from the top of a stack of sheets of like material. Suction cups are widely utilized in feeder mechanisms for picking up the sheets of material. Typically, the lip of the suction cup is driven into contact with the surface of the sheet. Suction or a partial vacuum inside the suction cup causes ambient air pressure to force the cup against the contact surface and so hold it by friction against the lip.
A more complete understanding of the present invention may be derived by referring to the detailed description and claims when considered in connection with the Figures, wherein like reference numbers refer to similar items throughout the Figures, and:
Sheet feeder apparatuses are used to pick up a variety of materials having different thicknesses, stiffness, sheet sizes, material quality and so forth. In some instances, it may be necessary to adjust positions of the pickup heads of a feeder mechanism for particular working conditions and/or types of material. With particular regard to stiff paper, such as cardstock, a typical stack of sheets may be curved upwardly or downwardly at its leading edge. As such, when the suction cups of vertically oriented pickup heads of a feeder mechanism are lowered to this curved surface, incomplete contact between the suction cups and the stack of curved sheets can occur causing an air leak between the lip of the suction cup and the topmost sheet. Accordingly, sufficient suction may not be formed and the sheet material may not be effectively held by friction against the lip of the suction cup. If the sheet material is not effectively held by the suction cups, feed-failure jams, overlapped feeding, and/or a number of other problems can occur. The term “feed-failure jam” refers to a condition in which a sheet of material is not well fed but stopped on the feeding path, which can lead to further complications. The term “overlapped feeding” refers to the condition in which more than one sheet is fed together, with a part of one sheet overlapped by a part of another sheet.
Embodiments disclosed herein entail a feeder mechanism in a sheet feeder apparatus for picking up sheets of a material from a stack of sheets. The feeder mechanism includes suction pickup heads that can be collectively adjusted, or tilted, in a sheet transport direction to accommodate curvature in the stack of sheets. Additionally, the suction pickup heads can be individually adjusted in a lateral direction perpendicular to the sheet transport direction to accommodate varying widths of the sheet material. The various adjustments can be readily accomplished on the fly in accordance with changing materials and conditions. Moreover, the feeder mechanism may be implemented on a variety of sheet feeder apparatuses without undue modification to the apparatuses.
Referring to
Feeder mechanism 28 is shown and described herein as being coupled with sheet feeder apparatus 20 for illustrative purposes. However, the elements of feeder mechanism 28 such as support bar 30, pickup heads 32, and adjuster 34 may be readily adapted for incorporation into other sheet feeder designs.
In an illustrative example, sheet feeder apparatus 20 may include two sets of control arms 36, each of which are located at opposing ends of pivot and forward control shafts 38 and 40, respectively. Each set of control arms 36 can include a first control arm 42 and a second control arm 44. Opposing ends of support bar 30 are constrained by, i.e., held by, first control arm 42. In general, pivot and forward control shafts 38 and 40, along with first and second control arms 42 and 44, function cooperatively to drive feeder mechanism 28 upwardly and downwardly, as well as forward and backward. That is, the opposing ends of support bar 30 reside in a frame cutout 46 (shown in
Support bar 30 is configured to pivotally couple to first control arms 42 of sheet feeder apparatus 20. In an example, the ends of support bar 30 are directed through apertures (not visible) in each of first control arms 42 and connect to drive elements (not shown) of sheet feeder apparatus 20 in a known manner. Accordingly, a longitudinal axis 52 of support bar 30 is arranged substantially perpendicular to sheet transport direction 26 of sheet feeder apparatus 20. As will be discussed in much greater detail below, support bar 30 can pivot about its longitudinal axis 52, where the degree of pivoting is controlled by adjuster 34. The pivot motion is represented by a curved, bi-directional arrow 54 in
The materials to be fed by sheet feeder apparatus 20 can come in various widths. Accordingly, pickup heads 32 may also be suitably adjusted in accordance with a width dimension 56 of sheet 24 in order to accommodate various widths of sheet 24. That is, pickup heads 32 are additionally lengthwise displaceable along support bar 30, where this lengthwise motion is represented by a straight bi-directional arrow 58, as will be discussed in greater detail below.
Referring to
In some embodiments, the cylindrical first and second ends 60 and 62 may be threaded onto or otherwise attached to the rectangular intermediate portion 64. However, in other embodiments, the cylindrical first and second ends 60 and 62 may be formed from a contiguous piece of machined metal. Intermediate portion 64 is illustrated as being discontinuous so that first and second cylindrical ends 60 and 62 and the rectangular cross-section of intermediate portion 64 can be readily visualized. It should be readily apparent, however, that support bar 30 does not include a discontinuous region, as shown in
Referring to
Suction tube 68 is coupled to a vacuum hose 74, which in turn goes to a conventional suction source (not shown). Accordingly, a hollow space 76 (shown in dashed line form in
A passage 80 extends through block element 66. Passage 80 is generally rectangular so as to match the generally rectangular cross-sectional shape of intermediate portion 64 of support bar 30. In addition, passage 80 is slightly larger than the cross-sectional dimensions of intermediate portion 64 so that block element 66 can slide relatively freely lengthwise along intermediate portion 64. However, passage 80 is small enough so that block element 66 cannot rotate about intermediate portion 64.
Pickup head 32 further includes a fastener element 82 having a shank 84 in threaded engagement with block element 66. Shank 84 is configured to extend at least slightly into passage 80. Fastener element 82 further includes a knob 86 coupled to shank 84. In operation, a user can turn fastener element 82 to move shank 84 out of passage 80 so that block element 66 can be slid along intermediate portion 64 of support bar 30 to a desired position. Once pickup head 32 is appropriately located, the user can turn fastener element 82 using knob 86 to move shank 84 into abutment with intermediate portion 64 so that pickup head 32 is secured in place. Accordingly, each of pickup heads 32 can be individually lengthwise displaced along intermediate portion 64 and then secured in non-pivotable engagement with support bar 30.
Referring now to
With particular reference to
With particular reference to
Now with particular reference to
Fastener 92 is engaged with each of bracket 88 and post 106, and is oriented substantially perpendicular to support bar 30. In an embodiment, fastener 92 includes a threaded shank 110 attached to an adjustment knob 112. At least one of bracket 88 and post 106 includes a corresponding threaded opening. For example, post 106 includes a threaded opening 114 (see
In operation, manual rotation of fastener 92 in a first direction, e.g., clockwise, via adjustment knob 112 draws bracket 88 toward post 106. Movement of bracket 88 toward post 106 causes the corresponding rotation of support arm 30 relative to pivot arm 90 due to the fixed engagement of bracket 88 with support arm 30. As support arm 30 pivots, all of pickup heads 32 coupled to support arm 30 will concurrently tilt in a predetermined direction. Similarly, manual rotation of fastener 92 in a direction opposite, e.g., counterclockwise, to the first direction via adjustment knob 112 urges bracket 88 away from post 106. Movement of bracket 88 away from post 106 causes corresponding rotation of support arm 30 relative to pivot arm 90, and the subsequent tilting of pickup heads 32 in the opposite direction. Spring element 118 urges bracket 88 away from post 106. However, spring element 118 compresses as needed when fastener 92 is manually rotated.
As shown, stack of sheets 22 underlying suction cup 70 is generally flat, i.e., not curved. As such, pickup head 32 is suitably positioned vertically so that as pickup head 32 is moved in downwardly in accordance with up/down motion 48 of control arms 36 (
Rotation of fastener 92 in clockwise direction 122 draws bracket 88 toward post 106 (
Pickup head 32 is tilted to suitably align with the curvature of stack of sheets 22. Accordingly, as pickup head 32 is moved downwardly in accordance with up/down motion 48 of control arms 36 (
Rotation of fastener 92 in counterclockwise direction 126 urges bracket 88 away from post 106 (
Accordingly, as pickup head 32 is moved downwardly in accordance with up/down motion 48 of control arms 36 (
In summary, embodiments of the invention entail a feeder mechanism in a sheet feeder apparatus for picking up sheets of a material from a stack of sheets. The feeder mechanism includes suction pickup heads that can be collectively adjusted, or tilted, forwardly or backwardly in a plane parallel to a sheet transport direction of the sheet feeder apparatus in order to accommodate curvature in the stack of sheets. Additionally, the suction pickup heads can be individually adjusted in a lateral direction perpendicular to the sheet transport direction to accommodate varying widths of the sheet material. The various adjustments can be manually accomplished by an operator on the fly in accordance with changing materials and conditions. Moreover, the feeder mechanism may be implemented on a variety of sheet feeder apparatuses without undue modification to the apparatuses.
Although the preferred embodiments of the invention have been illustrated and described in detail, it will be readily apparent to those skilled in the art that various modifications may be made therein without departing from the spirit of the invention or from the scope of the appended claims. That is, it should be appreciated that the exemplary embodiments are only examples, and are not intended to limit the scope, applicability, or configuration of the invention.
Claims
1. In a sheet feeder apparatus, a feeder mechanism for picking up sheets from a stack of sheets comprising:
- a support bar configured to pivotally couple to control arms of said sheet feeder apparatus, said support bar including a first end, a second end, and an intermediate portion between said first and second ends, at least one of said first and second ends being a cylindrical end;
- a pickup head coupled to said support bar at said intermediate portion; and
- an adjuster coupled to said support bar at said cylindrical end, said adjuster being configured to pivot said support bar to tilt said pickup head; wherein said adjuster comprises:
- a bracket fixedly coupled to said intermediate portion of said support bar;
- a pivot arm coupled to said cylindrical end of said support bar, said pivot arm being selectively pivotable about said cylindrical end of said support bar; and
- an adjustment mechanism coupled between said bracket and said pivot arm and adapted to pivot said support bar relative to said pivot arm and thereby tilt said pickup head, said adjustment mechanism including a post and a fastener, said post being in fixed engagement with said pivot arm, said post being displaced away from and aligned substantially parallel to said support bar, said fastener being engaged with each of said bracket and said post, and said fastener being oriented substantially perpendicular to said support bar, wherein one of said bracket and said post includes a threaded opening, said fastener is a threaded fastener that extends through said threaded opening, and rotation of said threaded fastener in a first direction draws said bracket toward said post to cause said pickup head to tilt in a sheet transport direction of said sheet feeder apparatus, and rotation of said threaded fastener in a direction opposite to said first direction urges said bracket away from said post to cause said pickup head to tilt in a direction opposite to said sheet transport direction.
2. A feeder mechanism as claimed in claim 1 wherein:
- a longitudinal axis of said support bar is arranged perpendicular to a sheet transport direction of said sheet feeder apparatus;
- said pickup head is suspended below said support bar and configured to be driven into contact with successive ones of said sheets; and
- said adjuster pivots said support bar about said longitudinal axis to selectively tilt said pickup head in a plane extending substantially vertically and in said sheet transport direction.
3-5. (canceled)
6. A feeder mechanism as claimed in claim 1 wherein said threaded fastener includes an adjustment knob for manual rotation of said threaded fastener.
7. In a sheet feeder apparatus, a feeder mechanism for picking up sheets from a stack of sheets comprising:
- a support bar configured to pivotally couple to control arms of said sheet feeder apparatus, said support bar including a first end, a second end, and an intermediate portion between said first and second ends, at least one of said first and second ends being a cylindrical end;
- a pickup head coupled to said support bar at said intermediate portion; and
- an adjuster coupled to said support bar at said cylindrical end, said adjuster being configured to pivot said support bar to tilt said pickup head wherein said adjuster comprises: a bracket fixedly coupled to said intermediate portion of said support bar; a pivot arm coupled to said cylindrical end of said support bar, said pivot arm being selectively pivotable about said cylindrical end of said support bar; and an adjustment mechanism coupled between said bracket and said pivot arm and adapted to pivot said support bar relative to said pivot arm and thereby tilt said pickup head, wherein said adjustment mechanism includes a post, a fastener, and a spring element, said post being in fixed engagement with said pivot arm, said post being displaced away from and aligned substantially parallel to said support bar, said fastener being engaged with each of said bracket and said post, said fastener being oriented substantially perpendicular to said support bar, and said spring element residing on said fastener and interposed between said bracket and said post.
8. A feeder mechanism as claimed in claim 1 further comprising multiple pickup heads coupled to said support bar at said intermediate portion, said pickup head being one of said multiple pickup heads, wherein pivoting said support bar concurrently tilts each of said pickup heads.
9. A feeder mechanism as claimed in claim 1 wherein said pickup head is in non-pivotable engagement with said support bar.
10. A feeder mechanism as claimed in claim 1 wherein said intermediate portion of said support bar has a generally rectangular cross section.
11. A feeder mechanism as claimed in claim 1 wherein said pickup head is lengthwise displaceable along said support bar.
12. A feeder mechanism as claimed in claim 1 further comprising multiple pickup heads coupled to said support bar at said intermediate portion, said pickup head being one of said multiple pickup heads, and each of said multiple pickup heads being individually lengthwise displaceable along said support bar.
13-18. (canceled)
19. In a sheet feeder apparatus, a feeder mechanism for picking up sheets from a stack of sheets comprising:
- a support bar configured to pivotally couple to control arms of said sheet feeder apparatus, said support bar including a first end, a second end, and an intermediate portion between said first and second ends, at least one of said first and second ends being a cylindrical end;
- multiple pickup heads coupled to said support bar at said intermediate portion; and
- an adjuster coupled to said support bar at said cylindrical end, said adjuster being configured to pivot said support bar to concurrently tilt each of said pickup heads, said adjuster including: a bracket fixedly coupled to said intermediate portion of said support bar; a pivot arm coupled to said cylindrical end of said support bar, said pivot arm being selectively pivotable about said cylindrical end of said support bar; and an adjustment mechanism coupled between said bracket and said pivot arm and adapted to pivot said support bar relative to said pivot arm and thereby tilt said each of said pickup heads, said adjustment mechanism including a post and a fastener, said post being in fixed engagement with said pivot arm, said post being displaced away from and aligned substantially parallel to said support bar, said fastener being engaged with each of said bracket and said post, and said fastener being oriented substantially perpendicular said support bar; wherein one of said bracket and said post includes a threaded opening, said fastener is a threaded fastener that extends through said threaded opening, and rotation of said threaded fastener in a first direction draws said bracket toward said post to cause said each of said pickup heads to tilt in a sheet transport direction of said sheet feeder apparatus, and rotation of said threaded fastener in a direction opposite to said first direction urges said bracket away from said post to cause said pickup head to tilt in a direction opposite to said sheet transport direction.
20. (canceled)
Type: Application
Filed: Nov 8, 2011
Publication Date: May 9, 2013
Inventor: James J. Keller (Tempe, AZ)
Application Number: 13/291,353