Background Art U. S. Patent Number 3,423,900, to Orsinger et al., dated January 28, 1969, and incorporated herein by reference, discloses what is called a continuous motion inserting machine. As described in the patent, a continuous motion inserting machine provides a collating-inserting machine operable without hesitations or dwells, and constructed and arranged to operate in a continuously flowing manner such that inserts and corresponding envelopes are brought together and the inserts filled into the envelopes while both are in continuous movement. This machine is drastically different from the typical incremental inserter machine in which the envelope is stopped during the entire step during which the insert is placed inside it. Since there are no periods of time in which the envelope is stopped in a continuous motion inserting machine, it is inherently faster and more efficient than incremental inserting machines.

To date, the concepts behind the Orsinger continuous motion inserting machine have not been widely implemented. This is because of mechanical and dynamic limitations inherent in its mechanism. The Orsinger inserter, an awkward, chain and gear operated machine, has a relatively high mass and it is difficult to change or adjust the synchronization between the inserter and envelope conveyors to allow for increased flexibility and different modes of operation.

Accordingly, there is room for improvement within the art.

Disclosure of the Invention It is an object of the invention to provide a continuous motion inserting apparatus and method that is an improvement over prior art continuous motion inserting apparatuses and methods.

It is a further object of the invention to provide an improved continuous motion inserting apparatus and method that is of a lower mass than prior art continuous motion inserting apparatuses and methods.

It is yet a further object of the invention to provide an improved continuous motion inserting machine that is easily able to have the synchronization between its insert and envelope conveyors adjusted.

These and other objects of the invention are achieved by a continuous motion inserting apparatus and method, comprising: an envelope conveyorfor feeding an envelope in a feed direction with its open end trailing during an insertion step; an insert conveyorforfeeding an insert in the feed direction from a position upstream of said envelope conveyor during the insertion step;

wherein during the insertion step the insert conveyor moves the insert at a speed greater than the envelope conveyor moves the envelope such that at a predetermined position the insert is entirely within the envelope; and wherein the insert and envelope conveyors are driven by first and second servo motor controlled mechanisms, respectively.

These and other objects of the invention are achieved by a method of inserting an insert into an open envelope, comprising the steps of: providing a servo motor controlled envelope conveyor for feeding an envelope in a feed direction with its open end trailing during an insertion step; providing a servo motor controlled insert conveyor for feeding an insert in the feed direction from a position upstream of the envelope conveyor at a speed greater than the envelope conveyor moves the envelope during the insertion step such that at a predetermined position the insert is entirely within the envelope.

Some of the objects of the invention having been stated hereinabove, other objects will become evident as the description proceeds, when taken in connection with the accompanying drawings as best described hereinbelow.

Brief Description of the Drawings Figure 1 is a plan view of a continuous motion inserting apparatus according to the present invention; Figure 2 is an elevation view of a continuous motion inserting apparatus according to the present invention; and

Figure 3 is an elevation view depicting the envelope presentation, registration, and opening location of a continuous motion inserting apparatus according to the present invention.

Best Mode for Carrying Out the Invention With reference to the above drawings, an improved continuous motion inserting apparatus and method that meets and achieves all the various objects of the invention set forth above will now be described.

Figures 1 and 2 show an exemplary embodiment of an improved continuous motion inserting apparatus 1 according to the present invention.

Continuous motion inserting machine 1 generally comprises insert conveyor subassembly 10 and envelope conveyor subassembly 50, respectively. Both conveyor subassemblies are preferably servo motor controlled mechanisms and operate to continuously feed their respective products, i. e., inserts and envelopes, respectively, in feed direction F without stopping for any substantial amount of time. During this feeding process, as will be described below, the two subassemblies also operate to place the insert within the envelope.

Insert feed conveyor subassembly 10 is most clearly shown in the plan view of Figure 2. Although it is preferred and described herein that subassembly 10 comprises side-by-side chain conveyors, it is possible to employ belt conveyors. Each chain 20 is wrapped around a pair of rotatable sprockets 25,25'. To drive each of the side by side conveyors, it is preferred to fixedly mount an adjacent pair of sprockets 25 on common drive shaft 27

and then connect drive shaft 27 to a servo motor 28 by a mechanical movement 29, such as a conventional belt and pulley combination. It is also possible to mount each sprocket 25 on its own axle and then connect each axle to its own servo motor 27. In either form, however, servo motor (s) 27 will be connected to a common electronic controller C as will be described below.

Tension sprockets 26 take up any slack in chains 20 and therefore control the tension in chains 20. Finally, each chain 20 has a plurality of pusher fingers 30,30', 35,35', 40,40', thereon. These pusherfingers 30,30', 35,35', 40,40' operate to push an insert I downstream in feed direction F and at a continuous and constant speed.

Envelope transport conveyor subassemblies 50,50'are mirror images of each other and together form the envelope transport conveyor that is used to transport envelopes E downstream in feed direction F and also at a constant speed with only momentary stopping during a registration step. From a remote source, envelopes E are fed to envelope transport conveyor subassemblies 50, 50', via a conventional envelope conveyor (Figure 3) feeding in the direction of arrow G.

Figure 3 is an elevation view depicting the envelope presentation, registration, and opening location 100. Location 100 includes a conventional rotating envelope drum 110, typically and preferably in the form of a rotating vacuum envelope drum 110 having an envelope gripping member 115 thereon and positioned below table surface T. Table surface T has a slot therein so that envelopes may be fed by envelope drum 110 from a position below table

surface T to a position above table T so that the envelope can be registered, opened, and filled.

To register envelope E in area 100, a registration mechanism 200, is used. Registration mechanism 200, preferably in the form of a front edge registration system, includes retractable lower portion 210 and stationary upper portion 220. Stationary upper portion 220 comprises a plurality of spaced apart vertical plates 220a. Retractable lower portion 210 comprises a moveable front stop 215 attached to a motor 217 through a suitable mechanical linkage 216.

The mechanical linkage converts the rotary motion of motor 217 in to the reciprocating motion of stop 215. However, any type of motor and any type of linkage may be used so long as stop 215 can be moved above or below table T.

When in its raised position, stop 215 interacts with vertical plates 220a to form a gate preventing envelopes from passing by. This gate also forms a front registration element. Therefore, as envelope E is fed into area 200 by envelope gripping member 115 of envelope drum 110, its leading edge will be brought into contact with the registration element 210,220, thereby registering and squaring the envelope E. The envelope E is momentarily stopped at this time.

Because, as described above, the envelope is momentarily stopped in the inserting apparatus according to the invention, it is not a true continuous inserting apparatus. However, this stop time (dwell) is both short in an absolute sense as well as in relation to the overall apparatus cycling time. Furthermore,

in the inserter apparatus according to the present invention, both the envelope and insert are in motion during the entire inserting step. In a conventional incremental inserter, not only is the stop time (dwell) much longer both in absolute and relative terms, the envelope is stationary during the entire inserting step. Accordingly, despite the small stop (dwell) time in the inserter according to the invention, the invention still better approximates the operation of a true continuous motion inserting apparatus and therefore can be labeled as such.

Afterthe envelope E is stopped, squared and registered, it is opened by envelope opening mechanism O. The form of envelope opening mechanism O plays no part in the invention and may take any form so long as cycling speeds of the continuous motion inserting apparatus in general are met.

However, typically envelope opening mechanism O will comprise some type of vertically movable vacuum element that is able to pull apart the walls of the envelope E.

Finally, after the envelope E is stopped, squared, registered, and opened, stop 215 is lowered to its position below table T and envelope transport conveyor subassemblies 50,50'take over the feeding of the envelope.

Envelope transport conveyor subassemblies 50,50'are most clearly shown in the plan view of Figure 1. Each envelope transport conveyor subassembly is also preferably a chain mechanism, like those that make up insert feed conveyor sub-assembly 10. Chains 55,55'are wrapped around

rotatable sprockets 56,57 and 56', 57', respectively. One of the two sprockets of each of envelope transport conveyors subassemblies 50,50'is connected to a servo motor 59,59'through a mechanical movement 60,60', such as a conventional belt and pulley system. It is also possible to commonly drive envelope transport conveyor subassemblies 50,50'by a common motor and drive (not shown). However, due to spacing and location concerns, it is simpler and easier to independently drive each envelope conveyor subassembly 50, 50'. Like servo motors 27, servo motors 59,59'are electronically connected to controller C.

For actually moving the envelopes again, each envelope transport conveyor chain 55,55'is provided with a plurality of opening fingers 65,66,67, 65', 66', 67'that work together in opposing pairs. Each opening finger may be similarly constructed from suitably formed sheet metal or plastic in an elongated channel-shaped cross-section having its forward end shaped and constructed, i. e., tapered, to facilitate entry into the mouth of an envelope.

Finally, opening fingers 65,66,67,65', 66', 67'continuously travel along the paths defined by chains 55,55'in the direction of arrows H and at a constant speed.

After the envelope is presented for insertion and momentarily stopped after registration, a pair of opposing opening fingers will swing around sprockets 56,56', and begin to enter the gap of the mouth of the presented and opened envelope along the envelope's opposite edges. As the opening fingers continue to be moved in feed direction F, they will continue entering the

envelope until fully inside. By that point, the opening fingers will have complete control of the envelope, feeding it downstream again as the opening fingers 65, 65', 66,66', 67,67'move downstream. Though the envelope was momentarily stopped from being fed, as described above, this time period is small in absolute terms as well as in relation to the inserter cycle speed that it results in a minimal delay, unlike the substantial delays incurred in prior art non- continuous (incremental) motion inserting apparatuses.

Within the engaged envelope, opening fingers provide, in effect, an insert receiving funnel opening rearward. To facilitate reception of inserts into the funnel thus provided, the fingers are desirably provided on their lower rear portions with flanges which may extend into close proximity of each other over the envelope flap (to hold the flap open).

As each envelope E is thus readied in the filling zone, inserts I are thrust by insert feed conveyor subassembly 10 through the opening fingers and into the envelopes E. The speed of insert feed conveyor subassembly 10 is set to a speed faster than that by which envelopes E are fed downstream in direction F by the envelope transport conveyor subassemblies 50,50'. Thus, inserts I will completely be inserted into envelopes E. As can be seen by this description, in the continuous motion inserter apparatus according to the invention the envelope is moved in a downstream direction as the envelope is being filled, i. e., during the insertion step. Other than during the short moment during the registration step, the envelope is continuously moving downstream and is not stationary.

The fact that the continuous motion inserter according to the invention provides for the use of servo motors to drive each the insert and envelope conveyors represents a large step forward in this technology.

In prior art continuous feeding apparatuses, such as described above and in U. S. Patent No. 3,423,900, to Orsinger et al., since all of the drive components are mechanically linked to each other, such as by chains and gears, the apparatus will not be able to have the synchronization between the envelope and insert conveyors easily changed. Being able to easily change this synchronization is important to a more efficient use of the continuous motion inserting apparatus. In particular, for different sized (e. g. length) forms, the location at which the insert is placed into the envelope will be different.

Similarly, for different thickness inserts, different operating speeds will be required so as to prevent jams. In prior art continuous motion inserting apparatuses such as described in Orsinger, changing the synchronization between insert and envelope conveyors requires difficult and time consuming processes. For example, gear ratios need to be changed and that can only be done by the replacement of one sized gear with another sized gear. This may require taking apart large portions of the continuous motion inserting apparatus to gain access to these components. Such taking apart is time consuming.

Other issues such as belt slippage and gear teeth mis-meshing can result in a mechanical system that easily goes out of synchronization. It is probably for these reasons that the Orsinger continuous motion inserter has not been implemented in working embodiments despite its advance in the art.

The continuous motion inserter according to the invention overcomes all these deficiencies to prior art continuous motion inserter and therefore allows for the practical implementation and use of continuous inserting theory. What allows for the implementation of the continuous motion inserting theory, i. e., keeping both the insert and envelope in motion for as long as possible and with as little stop (dwell) time as possible, in practical applications in the apparatus according to the invention and not in Orsinger is the use of independently controllable drive sources to drive each of the mechanical conveyors in the invention. As described above, the preferred type of independent drive sources comprises independently controllable servo motors. Because continuous motion inserting apparatus 1 uses independently driven servo motors, the apparatus will be of lower mass and inertia. Accordingly, lower power servo motors can be used and less power consumed during apparatus operation. Also, the low mass/inertia allows for some stopping motion to be introduced in the registration step, without any degradation in apparatus throughput or reliability.

Each of the independently controllable servo motors will be electronically connected to a common controller, such as in the form of a conventional microprocessor controlled computer. Data provided to this controller, whether in the form of look-up tables or directly entered data, will be used to control the synchronization of the various servo motors within the continuous motion inserter according to the invention. This synchronization allows for the start and stop times of each servo motor to be controlled as well as their speeds. By

adjusting these speeds, not only can the continuous motion inserter insert different sized inserts into different sized envelopes, it can also control apparatus throughput speed. Control of apparatus throughput speed is especially important with larger inserts that require more positive control in order to prevent jamming.

Through a user interface 300 of some type, the inserter operator (or the inserter itself) will be able to vary the synchronization by merely making selections either from a keyboard or other conventional input device or sensor.

The controller will then do the rest and no mechanical adjustments or changes will have to be made to the continuous motion inserter. This allows for instantaneous changes in apparatus configuration, a highly beneficial result.

Finally, while as described above the instant invention is not a true continuous motion inserting apparatus in as much as the envelope does momentarily stop during the registration step, but not during the insertion step, this time period in which the apparatus stops is small in absolute terms and in relation to the overall cycle speed that is has no practical effect on the inserting process and renders the inserting apparatus according to the invention a better approximation to a true continuous motion inserting apparatus than would be a conventional incremental inserter. Further, as described above, the low mass/inertia of the apparatus allows the small periods of stop time to be introduced without any degradation of apparatus throughput speed or reliability, thus still achieving the objects of the invention set forth above.

The above description is given with reference to a continuous motion inserting apparatus and method. However, it will be understood that various details of the invention may be changed without departing from the scope of the invention. Furthermore, the foregoing description is for purpose of illustration only, and not for purpose of limitation, as the invention is defined by the following, appended claims.

It will be understood that various details of the invention may be changed without departing from the scope of the invention. Furthermore, the foregoing description is for the purpose of illustration only, and not for the purpose of limitation, as the invention is defined by the following, appended claims.