Patent Grant
7040616
The present invention relates to a module for printing postage value, or other information, on an envelope in a high speed mass mail processing and inserting system. Within the printing module, the printing device may operate at a lower velocity than other parts of the system. To allow the documents to be slowed for printing without causing jams, the present invention overlaps documents as they are transported and printed at the reduced speed.
Inserter systems, such as those applicable for use with the present invention, are typically used by organizations such as banks, insurance companies and utility companies for producing a large volume of specific mailings where the contents of each mail item are directed to a particular addressee. Also, other organizations, such as direct mailers, use inserts for producing a large volume of generic mailings where the contents of each mail item are substantially identical for each addressee. Examples of such inserter systems are the 8 series, 9 series, and Advanced Productivity System (APS™) inserter systems available from Pitney Bowes Inc. of Stamford Conn.
In many respects, the typical inserter system resembles a manufacturing assembly line. Sheets and other raw materials (other sheets, enclosures, and envelopes) enter the inserter system as inputs. Then, a plurality of different modules or workstations in the inserter system work cooperatively to process the sheets until a finished mail piece is produced. The exact configuration of each inserter system depends upon the needs of each particular customer or installation.
Typically, inserter systems prepare mail pieces by gathering collations of documents on a conveyor. The collations are then transported on the conveyor to an insertion station where they are automatically stuffed into envelopes. After being stuffed with the collations, the envelopes are removed from the insertion station for further processing. Such further processing may include automated closing and sealing the envelope flap, weighing the envelope, applying postage to the envelope, and finally sorting and stacking the envelopes.
Current mail processing machines are often required to process up to 18,000 pieces of mail an hour. Such a high processing speed may require envelopes in an output subsystem to have a velocity in a range of 80-85 inches per second (ips) for processing. Leading edges of consecutive envelopes will nominally be separated by a 200 ms time interval for proper processing while traveling through the inserter output subsystem. At such a high rate of speed, system modules, such as those for sealing envelopes and putting postage on envelopes, have very little time in which to perform their functions. If adequate control of spacing between envelopes is not maintained, the modules may not have time to perform their functions, and jams and other errors may occur. In particular, postage meters are time sensitive components of a mail processing system. Meters must print a clear postal indicia on the appropriate part of the envelope to meet postal regulations. The meter must also have the time necessary to perform bookkeeping and calculations to ensure the appropriate funds are being stored and printed.
A typical postage meter currently used with high speed mail processing systems has a mechanical print head that imprints postage indicia on envelopes being processed. Such conventional postage metering technology is available on Pitney Bowes R150 and R156 mailing machines using model 6500 meters. The mechanical print head is typically comprised of a rotary drum that impresses an ink image on envelopes traveling underneath. Using mechanical print head technology, throughput speed for meters is limited by considerations such as the meter's ability to calculate postage and update postage meter registers, and the speed at which ink can be applied to the envelopes. In most cases, solutions using mechanical print head technology have been found adequate for providing the desired throughput of approximately five envelopes per second to achieve 18,000 mail pieces per hour.
However, use of existing mechanical print technology with high speed mail processing machines presents some challenges. First, some older mailing machines were not designed to operate at such high speeds for prolonged periods of time. Accordingly, solutions that allow printing to occur at lower speeds may be desirable in terms of enhancing long term mailing machine reliability.
Another problem is that many existing mechanical print head machines are configured such that once an envelope is in the mailing machine, it is committed to be printed and translated to a downstream module, regardless of downstream conditions. As a result, if there is a paper jam downstream, the existing mailing machine component could cause even more collateral damage to envelopes within the mailing machine. At such high rates, jams and resultant damage may be more severe than at lower speeds. Such damage often includes the result of moving envelopes crashing into the edges of stationary downstream envelopes. Accordingly, improved control and lowered printing speed, while maintaining high throughput rate in a mechanical print head mailing machine could provide additional advantages.
Controlling throughput through the metering portion of a mail producing system is also a significant concern when using non-mechanical print heads. Many current mailing machines use digital printing technology to print postal indicia on envelopes. One form of digital printing that is commonly used for postage metering is thermal inkjet technology. Thermal inkjet technology has been found to be a cost effective method for generating images at 300 dpi on material translating up to 50 inches per second. Thus, while thermal inkjet technology is recognized as inexpensive, it is difficult to apply to high speed mail production systems that operate on mail pieces that are typically traveling in the range of up to 80 to 85 ips in such systems.
As postage meters using digital print technology become more prevalent in the marketplace, it is important to find suitable substitutes for the mechanical print technology meters that have traditionally been used in high speed mail production systems. This need for substitution is particularly important as it is expected that postal regulations will require phasing out of older mechanical print technology meters, and replacement with more sophisticated digital based meters. Although digital print technology exists that is capable of printing the requisite 300 dpi resolution on paper traveling at 80 to 85 ips, such devices are so expensive as to be considered cost prohibitive. Accordingly, it would be beneficial to have a solution that would allow lower velocity digital print technology, like thermal inkjet technology, to be utilized with the high speed mail production systems.
Some systems that have been available from Pitney Bowes for a number of years address some related issues. These systems utilize R150 and R156 mailing machines using 6500 model postage meters installed on an inserter system. The postage meters operate at a slower velocity than that of upstream and downstream modules in the system. When an envelope reaches the postage meter module, a routine is initiated within the postage meter. Once the envelope is committed within the postage meter unit, this routine is carried out without regard to conditions outside the postage meter. The routine decelerates the envelope to a printing velocity. Then, the mechanical print head of the postage meters imprints an indicia on the envelope. After the indicia is printed, the envelope is accelerated back to close to the system velocity, and the envelope is transported out of the meter.
One problem with this current solution is that the conventional postage meters are inflexible in adjusting to conditions present in upstream or downstream meters. For example, if the downstream module is halted as a result of a jam, the postage meter will continue to operate on whatever envelope is within its control. This often results in an additional jam, and collateral damage, as the postage meter attempts to output the envelope to a stopped downstream module.
Another problem with the current solution is that it is very sensitive to gaps between consecutive envelopes. In the process of slowing down the documents, the gap between documents is reduced, and an error in the spacing between documents becomes more significant. The inserter may not be able to maintain controlled spacing between documents accurately enough to prevent collisions between consecutive envelopes during the slow down process. This problem is further exacerbated because the R150 and R156 mailing machines are a bit too long to have time to carry out the routine on the envelopes, and to still have some margin for error in the arrival of a subsequent envelope. As such, a module with better space utilization and less sensitivity to gap variations is desirable.
The present invention provides a transporting system and method for use in a high velocity document processing system using lower velocity print technology. A transport path through the system is made up of an upstream transport conveying spaced apart documents at a first transport velocity. This first transport velocity represents the high processing speeds available in current high speed inserter machines. Downstream of the upstream transport, a deceleration transport decelerates documents from the high speed to a lower print velocity before passing the documents to a print transport. Both the upstream transport and the lower speed print transport normally operate at their respective constant velocities. The deceleration transport adjusts to match the speeds of the respective upstream or downstream modules when receiving and passing documents from them.
Preferably, a sensor located at the deceleration transport, detects the presence of documents at the deceleration transport, and triggers the deceleration profile to be performed on the document. After it is sensed that a document has passed out from the deceleration transport, the deceleration transport must accelerate back to the higher transport velocity in order to receive the next document.
The deceleration transport is further controlled such that a leading portion of a document being decelerated overtakes a trailing portion of a downstream document that is already traveling at the lower print velocity in the control of the print transport. Unlike conventional systems, there is no need or attempt to rigorously maintain and control a gap between subsequent documents.
The invention further includes an overlapping arrangement whereby the lead portion of the upstream document is urged to overlap on top of the trailing portion of the downstream document when the upstream document overtakes the downstream document. Such overlapping arrangement may cause a rear portion of the lead document to be positioned downward relative to the overtaking upstream document. Alternatively, the upstream document may be upwardly biased, or some combination of upward and downward biasing may be used. In any case, the lead portion of the trailing document should be positioned overlapping on a trailing portion of a leading document.
The overlapped documents are transported to a print head contiguous with the print transport. The print head prints the desired marks on the overlapped documents as they pass beneath at the print transport velocity.
Further details of the present invention are provided in the accompanying drawings, detailed description and claims.
As seen in
Postage printing module 10, upstream module 20, and downstream module 30, all include transport mechanisms for moving an envelope 1 along the processing flow path. In the depicted embodiment, the upstream module 20 includes nip rollers 21 driven by motor 22. Similarly, the downstream module 30 includes a transport comprised of nip rollers 31 driven by motor 32. In the preferred embodiment, rollers 21 and 31 are hard-nip rollers to minimize variation. As an alternative to nip rollers, the transport mechanism and transport path may comprise sets of conveyor belts (like belts 14) between which envelopes are transported.
Print head 15 is preferably located near the output end of the print transport portion of the postage printing module 10. To comply with postal regulations the print head 15 should be capable of printing an indicia at a resolution of 300 dots per inch (dpi). In the preferred embodiment, the print head 15 is an ink jet print head capable of printing 300 dpi on media traveling at 50 ips. Alternatively, the print head 15 can be any type of print head, including those using other digital or mechanical technology, which may benefit from printing at a rate less than the system velocity.
In the preferred embodiment, the transport within print module 10 may be identified in several segments. At the upstream end of the postage printing module 10, a first segment is comprised of a set of deceleration roller nips 41 that are driven at a variable speed by servo motor 43. Downstream of the deceleration roller nips 41, the transport mechanism is a dual belt transport arrangement comprised of inlet rollers 11 and further downstream rollers 12 around all of which belts 14 are driven. In the preferred embodiment depicted in
In
As an envelope 1 travels through the system depicted in a preferred embodiment shown in
As an alternative to relying solely on sensors for sensing positions of documents, the controller 17 may receive encoder pulses from motors 22, 43, or 18. These pulses can be interpreted by controller 17 as displacements, and such displacement information may supplement the sensor information for greater accuracy. Known techniques for predicting positions of documents based on known past locations and subsequent velocities may also be used to determine when events should be triggered, as opposed to relying on sensors for immediate tripping of a routine.
A process for creating an overlap of consecutive envelopes using the embodiment of
The relative positions of lead and tail edges of documents during the overlapping process are further depicted over time in the graph in FIG. 6. On the vertical axis, positions within the system, including locations A, B, C, D, and E, are represented. The locations of documents within the system are therefore represented with respect to time by the lines on the graph. The locations on the vertical axis correspond to the locations shown in
As seen in
Shortly afterwards, as seen in
In
Once again referring to
As depicted in
Yet another alternative overlapping arrangement is depicted in
In a further alternative overlapping arrangement shown in
In
Preferably, displacements of the member 51 are measured by an encoder-like arrangement in which movement of holes 53 on the outer perimeter of the disc 52 are sensed by an optical sensor 54. The sensor 54 generates pulses corresponding to the movement of the holes 53 by the sensor 54. The pulses are communicated to controller 17 that interprets the pulses to identify lead edges of envelopes when a sufficient displacement has occurred over short enough of a time. Based on the detection of the lead edge, the print head 15 may print on a leading portion of the surface of an overlapped envelope.
A further feature to assist in proper printing on overlapped envelopes is depicted in FIG. 5. In preferred embodiments, print head 15 uses ink jet technology. Ink jet technology preferably prints onto surfaces of documents within a uniform range of distances below the print head 15. Accordingly, varying thicknesses resulting from overlapping, or from different thicknesses of mail pieces can result in potential difficulties. To address the problem of presenting surfaces a uniform distance below the print head 15, the embodiment in
Accordingly, rollers 13 with a belt 14 are fixedly positioned above the transport path. The top surfaces of the overlapped documents will consistently be controlled by the position of the rollers 13 and plane formed by belt 14. Meanwhile, below the transport path, rollers 61 are individually mounted and are vertically movable. Preferably, the rollers 61 are mounted on moving mounting arms 62, which are rotatably mounted at the end distal to the rollers 61. The moving mounting arms 62 are upwardly biased by springs 63. Thus, the position of the rollers 61 may vary relative to the upper plane formed by rollers 13 and belt 14 above, depending on the varying thickness of the overlaps, and of the mail pieces.
A further benefit of overlapping mail pieces is that upon the occurrence of a downstream jam, fewer mail pieces may be damaged. In
In contrast, in
Although the invention has been described with respect to preferred embodiments thereof, it will be understood by those skilled in the art that the foregoing and various other changes, omissions and deviations in the form and detail thereof may be made without departing from the spirit and scope of this invention.
| Number | Name | Date | Kind |
|---|---|---|---|
| 3994221 | Littleton | Nov 1976 | A |
| 4320894 | Reist et al. | Mar 1982 | A |
| 4364552 | Besemann | Dec 1982 | A |
| 4436302 | Frye et al. | Mar 1984 | A |
| 4538161 | Reist | Aug 1985 | A |
| Number | Date | Country |
|---|---|---|
| 3544359 | May 1987 | DE |
| 0244650 | Apr 1987 | EP |
| Number | Date | Country | |
|---|---|---|---|
| 20040113356 A1 | Jun 2004 | US |
