Vacuum Hold Down for Feeder Tray

Abstract

A vacuum apparatus holds flat printed product in a feeder tray of a document feeding apparatus. The apparatus is particularly useful for feeding sheet material such as newspapers one at a time from the bottom of a stack. The apparatus uses existing vacuum connections in the document feeder and is easily mounted to existing feeder trays as part of a retrofit.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority on U.S. Provisional Application Ser. No. 61/152,485 filed Feb. 13, 2009, which is incorporated herein by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to an apparatus for holding down flat products such as newspaper inserts, sheets, signatures and the like in a feeder tray. More particularly, the invention relates to a vacuum hold down apparatus for a feeder tray.

2. Description of the Related Art

In the graphic arts and newspaper industries, sheet feeding apparatus for feeding sheet material one at a time from the bottom of a stack are often employed to automatically feed flat printed or other products such as newspapers. The bottom conveyance type of document feeding apparatus is conventionally used as it is excellent for paper separating efficiency.

The bottom conveyance type of sheet feeding apparatus typically has two basic sections that operate together in coordinated fashion. First, a feeder tray provides a horizontal support on which a vertical stack of sheet material is loaded. Second, a feeding system located adjacent to the feeder tray feeds the flat printed or other products such as newspapers into other areas of the machine.

Devices for feeding sheet material from the bottom of a stack are typically of two types, friction feeders or gripper feeders. Friction feeders, under normal conditions, are very reliable in feeding sheets individually from the bottom of a stack. However, they are particularly susceptible to misfeeds and/or multi-feeds when subject to the harsh environment of feeding newspaper. Gripper feeders are more reliable for feeding sheets in harsh environmental conditions, but require precise complex control to assure pickup of single sheets (i.e., for prevention of misfeeds or multi-feeds).

Furthermore, vacuum suckers in a gripper feeder have a tendency to adhere to only the outer half of the jacket on voluminous newspapers having loose collections of other sections. In some city newspapers, the outermost jacket is simply used to receive a loose, side-by-side collection of other sections within itself and lacks a cooperating interleaving between the outer jacket and those sections there within. The tremendous weight and friction of those newspapers above the bottom one in the stack may cause the outer jacket to be feed while the contents of the jacket stay behind, thereby failing to feed the entire newspaper and resulting in frustrating, time consuming jam-ups of the equipment.

Conversely, if thin, single sheet articles such as inserts are attempted to be fed at the other extreme, the vacuum can bleed through to the next article above so that proper separation does not occur and more than one article at a time is fed. In addition, other problems such as static charge attraction between sheets, tacky or partially dried ink, and misalignment of the vertical stack of sheet material can also result in multi-feeds.

Thus, a need exists for an apparatus for holding down flat products such as newspaper inserts, sheets, signatures and the like in a feeder tray to insure proper paper separation. For best results, the sheet hold down process should be able to be performed automatically or semi-automatically.

SUMMARY OF THE INVENTION

The invention provides an apparatus for holding flat paper products in a feeder tray of a bottom conveyance type of document feeder to insure that sheet material feeds one at a time from the bottom of the stack. The invention also provides a vacuum hold down apparatus for a feeder tray that utilizes existing vacuum connections to the document feeder. The invention also provides a vacuum hold down apparatus for a feeder tray that is economical to build and easily mounted on to existing feeder trays as part of a machine upgrade or retrofit.

The invention utilizes a vacuum cross bar that is configured to mount on to preexisting feeder trays. Broadly speaking, the vacuum hold down apparatus comprises a base having a flat bottom surface for mounting the base to the feeder tray. The base has a top surface for receiving a flat product which is connected at a forward edge to the bottom surface. A third surface connects the bottom surface to the top surface at a rearward edge. A channel is proximately located on the top surface of the base in contact with the flat product. A hollow bore is proximately located in an interior portion of the base and is connected to the channel through a plurality of vacuum ports proximately located in the channel.

In one embodiment of the invention, the top surface has a curvilinear recess proximately located forward of the channel. The purpose of this recess is to provide a cavity for the folded end of the bottom newspaper to lie while the second newspaper in the stack rests against the vacuum channel and is restrained by the vacuum. The top surface has a forward facing angle to provide a slight gravity feed to the newspaper. In this embodiment, the third surface is an arcuate surface to provide additional clearance for the folded end of the stack of newspapers.

A longitudinal channel is centered on the angle portion of the top surface to provide a vacuum plenum. The purpose of this plenum is to hold the second flat paper product in the stack while the bottom product is fed. A series of holes intersect the channel and run the entire length. At the other end, the holes intersect a hollow bore that passes through the center of the base. The thru bore design is preferred from an ease of manufacturing perspective. One end of the bore is supplied with a standard threaded or press-fit fitting for insertions into the bore. The other end of the fitting is a standard threaded or quick-disconnect hose type fitting which is commonly available in the art. Standard flexible hosing is used to connect the vacuum hold down apparatus to the existing vacuum source of the machine. A throttling or metering valve maybe installed in the vacuum line to control the level of vacuum supplied. Automatic regulation of the vacuum is also considered within the scope of the invention. The other end of the bore has a standard threaded or press-fitted plug to seal the end of the cavity.

A counter bored hole is provided through the third surface which allows for the insertion of a bolt or machine screw to attach the vacuum hold down apparatus to the feeder tray. The counter bore allows the bolt or screw head to be recessed away from the flat paper product to preclude interference between the bolt and the flat product. A tee nut is provided to align the apparatus in the existing slots which are commonly part of a feeder tray. Bolt and tee nut size is variable and can easily be matched to any slots size.

In another embodiment, the invention comprises a wedged-shaped structure having a bottom surface for mounting the base to a feeder tray and an angled top surface for receiving a flat product. The top surface has a forward facing angle to provide a slight gravity feed to the newspaper and is connected at a forward edge to the bottom surface. A third generally vertical surface connects the bottom surface to the top surface at a rearward edge. A longitudinal channel proximately located on the top surface of the base is biased towards the rearward end of the top surface to provide vacuum to hold the trailing edge of the flat paper product during feeding. A hollow bore is proximately located in an interior portion of the base and is connected to the channel through a plurality of holes forming a vacuum port. A series of counter bored holes are provided to fasten the base to the feeder tray. The series of holes provides flexibility in mounting the base to the feeder tray and insures that the wedge is compatible with the multiple feeder tray slot arrangements commercially available. A means for attaching the base to a vacuum source is also provided.

The vacuum wedge base has a smaller longitudinally width than the curvilinear base and is preferably used in pairs proximately spaced at a distance equal to the width of a newspaper. A center wedge support is mounted in between the two small wedge bases to support the center of the newspaper pile. The vacuum connection to the two bases is a parallel source connection using standard hose as known in the art.

Those skilled in the art will further appreciate the above-mentioned advantages of the vacuum hold down apparatus, together with other important aspects thereof, upon reading the detailed description which follows in conjunction with the drawing.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other aspects of the present invention may be more fully understood by reference to one or more of the following drawings, in which:

FIG. 1 is a perspective view showing the external appearance of one embodiment of the invention installed on a feeder tray;

FIG. 2 is a perspective, simplified view of the invention of FIG. 1 showing certain internal structures;

FIG. 3 is a perspective view of the invention of FIG. 1 showing the interface with a flat product;

FIG. 4 is a perspective view showing the external appearance of an alternate embodiment of the invention; and

FIG. 5 is a perspective view showing the external appearance of an alternate embodiment of the invention installed on a feeder tray.

DETAILED DESCRIPTION OF THE INVENTION

A preferred embodiment of the invention will be described, but the invention is not limited to this embodiment.

The overall external appearance of one embodiment of a vacuum hold down apparatus 10 installed on feeder tray 12 is shown in FIG. 1. Vacuum hold down apparatus 10 comprises base 14 having flat bottom surface 16, FIG. 2, for mounting base 14 to feeder tray 12. Base 14 has top surface 18 for receiving flat product 20, FIG. 3. Top surface 18 is connected to bottom surface 16 at forward edge 22, FIG. 2. Third surface 24 connects bottom surface 16 to top surface 18 at rearward edge 26. Channel 28, FIGS. 1-3, is proximately located on top surface 18 of base 14 in contact with flat product 20, FIG. 3. Hollow bore 30 is proximately located in an interior portion of base 14. A plurality of vacuum ports 32, FIGS. 1-3, connect channel 28 to hollow bore 30.

In this embodiment of the apparatus 10, top surface 18 has curvilinear recess 34 proximately located forward of channel 28 as shown in FIGS. 1-3. The purpose of recess 34 is to provide a cavity for the folded end of the bottom newspaper 20 to lie while the second newspaper 20 in the stack (not shown) rest against vacuum channel 28 and is restrained by the vacuum. Top surface 18 has forward facing angle 36, FIG. 2, to provide a slight gravity feed to newspaper 20. In this embodiment, third surface 24 is an arcuate surface to provide additional clearance for folded end of the stack (not shown) of newspapers 20.

As shown in FIG. 1, one end of base 14 is supplied with standard threaded or press-fit fitting 40 for insertions into bore 30, FIG. 2. The other end of fitting 40 is a standard threaded or quick-disconnect hose type fitting which is commonly available in the art. Standard flexible hosing 42 is used to connect vacuum hold down base 14 to existing vacuum source 44. A throttling or metering valve (not shown) maybe installed in the vacuum line to control the level of vacuum supplied. The other end of base 14 has standard threaded or press-fitted plug 46 to seal the end of bore 30, FIG. 2. Counter bored hole 50 is provided through third surface 24 for bolt or machine screw 52. Bolt or machine screw 52 with washer 54 and tee nut 56 are used to attach the vacuum hold down apparatus 10 to feeder tray 12.

Base 14 is preferentially made of aluminum or stainless steel and fabricated using conventional machining processes, although molded composite or resin processes may be used to form base 14.

In another embodiment as shown in FIG. 4, the apparatus 10 comprises wedged-shaped structure 60 having bottom surface 62 for mounting structure 60 to feeder tray 12. Angled top surface 64 for receiving flat product (not shown) has forward facing angle 66 to provide a slight gravity feed to newspaper (not shown) and is connected at forward edge 68 to bottom surface 62. Third generally vertical surface 70 connects bottom surface 62 to top surface 64 at rearward edge 72. Longitudinal channel 74 proximately located on top surface 64 of structure 60 is biased towards rearward end 72 of top surface 64 to provide vacuum to hold the trailing edge of the flat paper product (not shown) during feeding. Hollow bore 76 is proximately located in an interior portion of structure 60 and is connected to channel 74 through holes 78 forming a vacuum port. Series of counter bored slots 80 are provided to fasten structure 60 to feeder tray 12 using bolt or machine screw 84, FIG. 5.

As shown in FIG. 5, vacuum wedge base is preferably used in pairs 90, 92. Left wedge-shaped base 90 has inner vertical edge 90a and outer vertical edge 90b. Right wedge-shaped base 92 has inner vertical edge 92a and outer vertical edge 92b. The spacing of left base 90 with respect to right base 92 on feeder tray 12 is such that outer vertical edge 90b of left base 90 is spaced proximately equal to the width of a newspaper (not shown) from outer vertical edge 92b of right base 92. Center wedge support 94 is mounted in between wedge bases 90, 92, proximately spaced equidistance from inner edge 90a of left base 90 and inner edge 92a of right base 92 to support the center of the newspaper pile (not shown). Bolt or machine screw 96 attaches center support 94 to feeder tray 12. Vacuum connection 98 is a parallel source connection using standard hose as known in the art to supply vacuum to bases 90, 92.

Although only a few embodiments of the present invention have been described, the invention is, nonetheless, to be broadly construed, and is not to be limited to these embodiments, and the scope is defined by the claims appended hereto. Those skilled in the art will recognize the above-described features and advantages of the invention and that various substitutions and modifications may be made without departing from the scope and spirit of the appended claims.

REFERENCE CHARACTERS

10 Vacuum Hold Down Apparatus

12 Feeder Tray

14 Base

16 Bottom Surface

18 Top Surface

20 Flat product

22 Forward Edge

24 Third Surface

26 Rearward Edge

28 Channel

30 Hollow Bore

32 Holes

34 Curvilinear Recess

36 Forward Facing Angle

40 Fitting

42 Hose

44 Vacuum Source

46 Plug

50 Hole

52 Bolt or Machine Screw

54 Washer

55 Tee Nut

60 Wedge Shaped Base

62 Bottom Surface

64 Angled Top Surface

66 Forward Facing Angle

68 Forward Edge

70 Third Vertical Surface

72 Rearward Edge

74 Channel

76 Hollow Bore

78 Holes

80 Slots

84 Bolt or Machine Screw

90 Left Base

90a Inner Vertical Edge

90b Outer Vertical Edge

92 Right Base

92a Inner Vertical Edge

92b Outer Vertical Edge

94 Center Support

96 Bolt or Machine Screw

98 Vacuum Supply Hose

Claims

1. A vacuum hold down apparatus for a feeder tray, comprising:

a base having a bottom surface for mounting the base to the feeder tray, a top surface for receiving a flat product and connected at a forward edge to the bottom surface, and a third surface for connecting the bottom surface to the top surface at a rearward edge;

a channel proximately located on the top surface of the base;

a hollow bore proximately located in an interior portion of the base; and

a plurality of vacuum ports proximately located in the channel and connecting the channel to the hollow bore.

2. The vacuum hold down apparatus of claim 1, wherein the top surface has a curvilinear recess proximately located forward of the channel.

3. The vacuum hold down apparatus of claim 1, wherein the third surface is an arcuate surface.

4. The vacuum hold down apparatus of claim 1, wherein the base is a wedged shaped structure.

5. The vacuum hold down apparatus of claim 1 further comprising:

a means for fastening the base to the feeder tray.

6. The vacuum hold down apparatus of claim 5, wherein the means for fastening the base to the feeder tray is a nut and a bolt or a nut and a machine screw.

7. The vacuum hold down apparatus of claim 1 further comprising:

a means for attaching the base to a vacuum source.

8. The vacuum hold down apparatus of claim 7, wherein the means for attaching the base to a vacuum source is a hose.

9. An apparatus for holding flat paper products in a feeder tray, comprising

at least one base having a bottom surface for mounting the base to a feeder tray, a top surface for receiving a flat product and connected at a forward edge to the bottom surface, and a third surface for connecting the bottom surface to the top surface at a rearward edge, a channel proximately located on the top surface of the base, a hollow bore proximately located in an interior portion of the base, and a plurality of vacuum ports proximately located in the channel and connecting the channel to the hollow bore;

a first fastener for fastening the base to the feeder tray; and

a second fastener for attaching the base to a vacuum source.

10. The apparatus for holding flat paper products of claim 9, wherein the first fastener the base is a nut and a bolt or a nut and a machine screw.

11. The apparatus for holding flat paper products of claim 9, wherein the second fastener is a hose.

12. The apparatus for holding flat paper products of claim 9 further comprising:

at least one left wedge shaped base having an inner vertical edge and an outer vertical edge; and

at least one right wedge shaped base having an inner vertical edge and an outer vertical edge, proximately spaced from the left base on the feeder tray whereby the distance between the outer vertical edge of the left base and the outer vertical edge of the right base is proximately equal to the width of a newspaper.

13. The apparatus for holding flat paper products of claim 12 further comprising:

at least one wedge shaped support positioned between the left base and the right base on the feeder tray, proximately spaced equidistance from the inner edge of the left base and the inner edge of the right base; and

a third fastener for attaching the support to the feeder tray.

14. A method for holding flat paper products in a feeder tray, comprising the steps of:

providing at least one base having a bottom surface for mounting the base to a feeder tray, a top surface for receiving a flat product and connected at a forward edge to the bottom surface, and a third surface for connecting the bottom surface to the top surface at a rearward edge, a channel proximately located on the top surface of the base, a hollow bore proximately located in an interior portion of the base, and a plurality of vacuum ports proximately located in the channel and connecting the channel to the hollow bore;

fastening the base to the feeder tray;

attaching the base to a vacuum source; and

applying vacuum.