Abstract:
In connection with a method for automatically inserting documents to be displayed on a display device and/or copied in a digitizing device, such as microfiches, microfilm jackets or the like, in which process one document at a time is transported from a stack of documents to be processed to a document support and from there to a deposit magazine for the processed documents, provision is made according to the invention that the top document of a stack of documents contained in the holding magazine is pulled up by suction to about the level of the document support and the remaining stack is subsequently retained by suction acting in the opposite direction; the document pulled up by suction is transported sideways to the document support, and deposited on said support by terminating the suction effect, and the document is then picked up by suction again after it has been processed, and is transported to the deposit magazine.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     Applicants claim priority under 35 U.S.C. §119 of German Application Nos. 100 17 989.4, filed on Apr. 11, 2000, and 100 55 159.9, filed on Nov. 7, 2000. Applicants also claim priority under 35 U.S.C. §120 of PCT/DE01/00782, filed on Feb. 28, 2001. The international application under PCT article 21(2) was not published in English. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The invention relates to a method for automatically inserting documents such a microfiches, microfilm jackets or the like to be displayed on a display device and/or copied in a digitizing device. In this method, documents are conveyed one at a time from a holding magazine from a stack of documents to be processed to a document support, and from there to a deposit magazine for the processed documents. The invention, furthermore, relates to a device for carrying out the method. 
     2. The Prior Art 
     In light of the fact that the amount of documents that has to be digitized for more comfortable handling and for space reasons in companies, administrative offices and hospitals has grown in the course of time, the time factor plays an important role in connection with the digitizing and filing of such documents. 
     A commonly employed method for said purpose is to insert the documents individually under the digitizing device by hand and to remove them again manually after they have copied and digitized. 
     Due to the complicated handling of the documents during feeding, for example when processing microfilm jackets, a put-through of only 30 to 60 jackets per hour can be achieved, which means that new jackets would have to be continually inserted by hand at about 1- to 2-minute intervals. This requires the constant presence of a person while the digitizing device is being operated. 
     Patent application 198 46 899.7 describes an automated method and a device adapted to said method. It is possible with the help of said method and device to significantly increase the processing speed. The device described in said patent operates with purely mechanical means, which makes the device susceptible to trouble and maintenance-intensive. 
     SUMMARY OF THE INVENTION 
     Therefore, the invention is based on the problem of controlling or designing a method and a device of the type specified above in such a manner that the expenditure in terms of engineering expenditure remains low; that only a few moving parts are present; and that a reliable mode of operation is achieved nonetheless. 
     The invention solves this problem in that the top document is lifted up by suction from a stack of documents contained in a holding magazine, to about the level of the document support, and the remaining stack is subsequently kept in the holding magazine by suction in the opposite direction; the document pulled up by suction is then transported to the document support sideways and deposited on the document support by cancelling the suction effect. After the document has been processed, it is lifted up again by suction and transported to the deposit magazine. 
     A possible way of controlling the method is represented by the following sequence: 
     The holding magazine is filled. 
     No document is present on the document support. 
     The deposit magazine is emptied. 
     The pump generating the suction effect is shut off. 
     The suction element is positioned above the filled magazine, while the depositing element is positioned above the still-empty deposit magazine. 
     The suction device is started. 
     At least one document is lifted from the stack by suction. 
     This causes the vacuum to rise and a limit pressure valve is opened. 
     Any other document that may adhere to the document is removed and sucked back into the magazine; the remaining stack is retained. 
     The vacuum is controlled down to a lower value. 
     The document lifted by suction is displaced sideways to the document support. 
     The suction device is shut off (so that the vacuum will rapidly break down; either a bypass valve is opened and the outlet side of the suction device is briefly closed, or the drive of the suction device is slowed down electrically or mechanically). 
     The vacuum breaks down; the document drops onto the document support. 
     The document is digitized. 
     Following digitizing, the document is lifted from the document support by suction effect as well and transported to the deposit magazine. 
     Simultaneous with the lifting of the digitized document from the document support, the next document is collected from the holding magazine by suction. 
     According to a preferred way of controlling the method, in connection with which the limit pressure valve and the second conveyor means transporting the processed document from the document support to the deposit magazine are omitted, the operational sequence is as follows: 
     The holding magazine is filled. 
     No document is present on the document support. 
     The deposit magazine is emptied. 
     The transport means lifting the document by suction is positioned on top of the filled magazine. 
     The suction device located in the transport means is started. 
     At least one document is lifted from the stack by suction. 
     The suction openings in the transport means are closed, which either actuates a microswitch arranged within the zone of said suction openings, said microswitch generating a signal for cancelling the return suction effect (such a sensor may be located also in another site). 
     The documents lifted by suction is displaced sideways to the document support. 
     The suction device in the transport means is shut down. 
     The vacuum breaks down; the document drops onto the document support. 
     The transport means is driven away from the document support sideways. 
     The document is digitized. 
     Following digitizing, the document is again picked up from the document support by the transport means and transported to the deposit magazine. 
     After the transport means has ejected the processed document into the deposit magazine, it drives back into the original position above the holding magazine and the sequence starts anew. 
     A device according to a preferred embodiment is employed in connection with this second variation of the method. This device is characterized in that the plane board provided with the suction openings is part of a housing that is displaceable on guides and divided in two part areas by means of a partition wall, whereby one of the part areas is arranged located above the suction openings and can be evacuated by means of a suction blower arranged in the second part area, whereby the second part area has an opening that is aligned with an opening in the holding magazine so that the air aspirated from the first part area is received in the double-walled bottom part of the holding magazine. 
     This means that as long as no document adheres to the plane board, covering the suction openings located there, the air moved by the suction blower circulates through the openings in the double-walled bottom area that are aligned with each other, and from there through the openings in the side walls of the magazine and then through the suction openings in the plane board to the suction blower. 
     Now, when a document engaged by suction adheres to said plane board, the suction openings are closed and the flow of air is interrupted. 
     A second suction blower located in the bottom zone of the holding magazine is now activated, causing the inner cavity in the holding magazine to be evacuated, so that the remaining stack present in the container is retained and only one single document actually adheres to the plane board of the transport means. As stated above, provision may be made in the plane board for a microswitch serving as the means for triggering the second suction blower, said microswitch being pressed through the document engaged by suction. 
     Such a microswitch, furthermore, offers the advantage that the document is actively repelled by spring force of said microswitch, which supports the effect of gravity. 
     A second possibility for triggering the second suction blower is to make provision in the flow of air of the first suction blower for a microswitch that is deflectable against the force of a spring. Said microswitch pivots back into its switching position when the flow of air is interrupted as a document is being engaged by suction. 
     The aspirated document is deposited on a document support which, according to a further embodiment, preferably comprises a framework corresponding with the document. A glass panel covering the document is pivot-mounted on this frame. 
     The glass panel needs to be arranged on the frame only when required because it is not absolutely required when microfiches are digitized, but needed for digitizing microfilm jackets. 
     According to a further embodiment, the frame consists of hollow profiles, whereby the profile walls disposed on the inner side have openings at their ends pointing at the document, and the cavities in the hollow profiles can be evacuated. The profile walls of the frame disposed on the inner side have a defined inclination, so that when the document to be digitized drops down, a self-centering effect is achieved. As soon as the document is positioned in the frame, the cavities of the frame are evacuated, so that a vacuum is generated below the document that flatly presses the document against the support. 
     As stated above, the vacuum suffices for completely pressing a microfiche plane against the support without the need of having to place a glass panel on the microfiche. 
     When a microfilm jacket is processed, the application of the vacuum causes the underside of the microfilm jacket to be pressed against the support. However, the pocket-shaped receiving strips for receiving the document do not possess such planeness, so that it is necessary in this case to additionally attach a glass panel. 
     After the digitizing process has been completed, the glass panel is swiveled away upwards. The vacuum below the document is still maintained so that the document cannot remain adhered to the glass panel driving up. 
     As soon as the glass panel has been swiveled away to the rear, the transport means drives on top of the document support and engages the digitized document by suction. On the way to the holding magazine, the transport means ejects the documents above the deposit magazine. According to claim  20 , the deposit magazine is located on the bottom of a housing that is provided with an opening at its upper side corresponding with the dimensions of the document. A guide means is extending from said opening to the deposit magazine. Said guide means is designed in such a way that the document dropping through the opening describes a path turning the document by 180°. 
     According to a further embodiment, the glass panel flattening the documents is secured with play on two U-shaped cantilevered arms. The cantilevered arms can be pivoted by means of an electric motor, swiveling from the covering position to a release position. The U-shaped cantilevered arms extend beyond the profile of one side of the frame of the document support. A driving means is secured on the shaft of the electric motor. During rotation, the driving means takes along a pin secured on one of the cantilevered arms, thereby causing the glass plate secured on the cantilevered arms to be pivoted upwards. 
     This construction has the advantage that the glass panel can be pivoted upwards by hand as well without actuating the motor. 
     The glass panel must not be supported in any rigid manner so as to assure that it will always rest plane on the document in each case. 
     According to a further embodiment, the glass panel is secured on the cantilevered arms by means of a ribbon that is adhesive on both sides. This adhesive ribbon is elastic and acts like another bearing permitting a smaller angular clearance. The bearings of the cantilevered arms have a certain play as well. 
     In addition, near the adhesive connection, the cantilevered arms may comprise an additional joint permitting a clearance of a few angular degrees. 
     According to a further embodiment, the deposit magazine is arranged located between the holding magazine and the document support. This results in shorter distances for the transport means to travel. 
     However, it is possible also, according to a further embodiment, that the document support is arranged between the holding magazine and the deposit magazine. Especially in connection with such an embodiment, provision is made according to a further embodiment that a second transport means is provided for transporting the document from the document support to the deposit magazine. The second transport means is capable of pivoting by an angle of about 150° anticlockwise, and by about 210° clockwise, in a plane extending perpendicular to the plane of the document support. The advantage of such an embodiment lies in that as the processed document is being picked up by said second transport means, the first transport means is capable of engaging by suction a new document for digitizing. 
     The second transport means pivots the document it has picked up by suction in such a manner that it comes to rest in a slanted plane. When the suction effect is cancelled, the document can then slide from there into the deposit magazine under the influence of gravity, coming to rest in the deposit magazine turned by 180° in relation to its starting position. As also in connection with the first alternative, what is achieved in this way is that the processed documents can be collected again from the deposit magazine in the same sequence, i.e. the documents are deposited in the deposit magazine in the same order as in the holding magazine. 
     According to a further embodiment, in the course of the pivoting movement of the second transport means, slots provided in the pivot guide open and then connect the suction opening or openings in the board with the suction device or separate such opening(s) from the latter. 
     In connection with a transport means of the last-mentioned type, it is possible to primarily establish a connection with the atmosphere by way of closable openings positioned above the suction openings in the transport means. The release of the document from the slanted board of the transport means is supported and facilitated in this way by the effect of gravity. 
     With all variations of the invention, it is absolutely necessary for the “separation” function for separating the documents in the holding magazine that a gap is available between the board provided with the suction openings and the top edges of the side parts of the holding magazine. Without such a gap, it is not possible to remove another document—which may adhere to the first document previously engaged by suction—by suction in the opposite direction. The width of the gap can be set by means of elevations provided on the top edges of the side parts. Such elevations may serve at the same time as guides for displacing the board sideways. 
     However, it is preferred that provision is made that such gap areas are produced, for example by wheels on which the transport means can be driven. The wheels are dimensioned in such a way that the bottom clearance of the transport means is adequate for producing the gap. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The invention is explained in greater detail in the following with the help of drawings, in which: 
     FIG. 1 shows the basic structure of a first variation of the invention. 
     FIG. 2 is a sectional view of the holding magazine with the transport means arranged thereon, in a first embodiment according to variation  1 . 
     FIG. 3 shows the arrangement according to FIG. 2 in a second embodiment according to variation  1 . 
     FIG. 4 shows a second variation of the device. 
     FIG. 5 is a sectional view of the holding magazine with the transport means positioned on top of the magazine. 
     FIG. 6 shows the bottom plate of the transport means with suction openings. 
     FIG. 7 is a partly sectional side view of a document support. 
     FIG. 8 shows the document support according to FIG. 7 with the transport means positioned on top; and 
     FIG. 9 is a sectional view of the document support with the inserted document and the glass panel placed on top. 
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     FIG. 1 basically represents a device for digitizing documents such as microfiches, microfilm jackets or the like. The device is generally denoted by reference numeral  1 . 
     Device  1  substantially comprises three components, notably the document feed system  2 , the actual digitizing device  3 , which, however, is only indicated, and the document discharge system  4 . Diqitizing device  3  comprises digitizer  33  and a document support  5 . 
     Document feed system  2  comprises a holding magazine  6  and a transport means  7  arranged above magazine  6 . Transport means  7  picks up the document from holding magazine  6  and drives sideways on top of document support  5 , on which the document is then deposited. 
     Holding magazine  6  is shown in greater detail in FIGS. 2 and 3. Transport means  7  comprises a plane board  8 , in which provision is made for the suction openings  9 . Suction openings  9  feed into a box-shaped chamber  10 , which is arranged on board  8 . A line  11  consisting of a flexible hose is connected with the upper wall of box  10  and leads to a vacuum pump  12 . Another line  13  also consisting of a flexible hose is connected in the bottom of holding magazine  6  and connected to vacuum pump  12  as well. A limit pressure valve  14  is arranged in line  13 . So as to assure that the document is engaged by suction, a connection is provided leading from line  13  to the environment. Such a connection can be established in the form of a permanently open bypass line  30  located above valve  14 . Alternatively, valve  14  can be designed so that when line  13  is not connected with the line  20  (at low or no vacuum), line  13  is connected with the environment via an additional connection. When valve  14  connects lines  13  and  20  (at high vacuum), the connection of line  13  to the environment is closed. A bypass line  15  with a bypass valve  16  leads from limit pressure valve  14  to the line  11 . Discharge device  4  comprises a deposit magazine  17  as well as another transport means  18 , which may consist of a board-like element as well, in which provision is made for at least one suction opening. Board  18  is pivot-mounted, swinging about the axle of rotation  19 . The suction opening provided in board  18  is connected with vacuum pump  12  via openings (not shown) located in the zone of rotary axle  19  and via a line  20  consisting of a flexible hose. When board  18  is in the position shown by dashed lines, the openings in the zone of rotary axle  19  are open, whereas they are closed when the board is in the position indicated by the fully drawn lines. 
     When in the position indicated by the dashed lines, board  18  is displaced sideways over document support  5 . However, board  18  can be arranged also so that the position above document support  5  is assumed by displacing the board from the position shown by the fully drawn lines into the position indicated by the dashed lines solely by means of the swiveling motion. 
     Furthermore, a closable opening is provided in the board  18 . 
     The operational sequence is explained with the help of FIG. 1 as follows: 
     The holding magazine  6  is filled with a stack of documents. The limit pressure valve  14  and the bypass valve  16  are closed. The transport means  7  is positioned above the holding magazine. A gap  21  is present between the board  8  of the transport  7  and the top edge of the holding magazine  6 . The top document in the holding magazine  6  is engaged by suction by the transport means  7  and closes the suction openings  9  as it is being picked up. The limit pressure valve  14  is now opened. The stack of documents remaining in the holding magazine  6  is engaged by suction and any other documents that might possibly adhere to the document being picked up by suction are engaged by suction at the same time. The vacuum is controlled down to a lower value. The transport means with the document adhering to it is displaced sideways over the document support  5 . The vacuum pump is shut off. So that the vacuum is cancelled rapidly and the document can drop onto the document support  5 , the bypass valve  16  is opened. Alternatively, it is possible also to briefly close the blow-off side of the vacuum pump, or the motor of the vacuum pump can be braked electrically or mechanically. 
     After the document has been placed on the document support  5 , the transport means  7  drives back into its starting position. The document is now digitized in the digitizing device  3 . After the digitizing process has been completed, the transport means  18  drives on top of the document support  5 . The openings within the zone of rotation  19  of the board  19  are opened, which establishes the connection with the vacuum pump. By swiveling the board  18  by about 210° clockwise, the board  18  is laterally received on the deposit magazine  17 . The openings within the zone of rotation  19  of the board are closed again by the swiveling movement and the additional opening provided in the board  18  is opened, so that a pressure compensation with the environment occurs. The document automatically slides into the deposit magazine  17 . 
     As the document is being attached by suction to the board  18  from the document support  5 , the next document is picked up by suction by the transport means  7  at the same time while the limit pressure valve  14  and the bypass valve  16  are being closed, and the operational sequence of the process is repeated as described above. 
     Owing to the fact that the board  18  is pivoted after the suction process by approximately 210° clockwise, the documents are received in the deposit magazine in the correct sequence, but turned by 180°. 
     FIGS. 2 and 3 show two exemplified embodiments of holding magazine  6  with associated transport means  7 . Holding magazine  6  comprises a container with a double-walled bottom part  22  and the side parts  23 , which are double-walled as well. Provision is made for the openings  24 ,  25  both in the inner wall of bottom part  22  and in the inner wall of side parts  23 , whereby openings  25  in the side parts can be closed. 
     The elevations  26  are attached to the top edges of side parts  23 . Elevation  26  serve for creating the gap  21  between holding magazine  6  and board  8  of transport means  7 . 
     The closable openings  25  in the area of the inner walls of the side parts  23  serve for optimizing the flow conditions when the top document is picked up by suction from the document stack  27  (openings  25 =closed), as well as when sucking back documents adhering to the documents lifted by suction (openings  25 =opened). 
     The representations in FIGS. 2 and 3 are different only on account of the dimensions of the elements described above and are therefore denoted by the same reference numerals. 
     FIG. 4 shows a preferred embodiment of the device as defined by the invention. 
     This device comprises a holding magazine  40 , which is shown in FIG. 5 on a larger scale; a deposit magazine  41 ; and a document support  42 , which is shown in FIGS. 7 to  9  in greater detail. As shown in FIGS. 4 and 5, a transport means for the documents to be processed is positioned above holding magazine  40  and generally denoted by the reference numeral  43 . 
     Holding magazine  40  is located in the upper zone of a housing  44  so that the side parts of holding magazine  40  are double-walled and that the bottom of the magazine is double-walled as well. The slot-shaped openings  46  are located in the inner side walls  45 , whereas the inner bottom of holding magazine  40  forms a closed surface. An opening  47  is located laterally next to holding magazine  40  in the top side of housing  44 . Opening  47  is separated from holding magazine  40  by means of a partition wall  48  not extending all the way down to the bottom of housing  44 . 
     As shown in FIGS. 4 and 5, a transport means  43  that can be displaced sideways is positioned above holding magazine  40 . Transport means  43  has a housing  49 , which is divided in the two part areas  51  and  52  by means of a partition wall  50 . Larger part area  52  is located directly above holding magazine  40  and has the suction openings  54 , which are arranged in the form of a matrix in the bottom area  53 . An opening  55  is provided in bottom part  53  of the part area  51 . When in the position shown, opening  55  is aligned with opening  47 . A suction blower  56  is arranged in the partition wall  50 . Blower  56  exhausts air from part area  52  and thus through suction openings  54  from the holding magazine, and blows the exhausted air into housing  44  via opening  55  and opening  47 . 
     The transport means  43  or housing  49  can be displaced sideways on the rails  57  by means of the wheels  75 . The wheels  75  and the rails  57  are arranged in this connection in such a way that an air gap remains available between the top side of the housing  44  and the bottom area  53  of the transport means  43 . 
     Another suction blower  59  is arranged in housing  44 , namely in the side wall  58 . Additional suction blower  59  evacuates the interior of housing  44 . In the present exemplified embodiment, the aspirated air is blown through an opening in the housing  60  of the deposit magazine  41  and into deposit magazine  41 . Deposit magazine  41  is located in the lower area of housing  60 , notably at the end of a curved guide means  61 , which starts at the top side of housing  60 . Provision is made there for an opening  62 . The dimensions of opening  62  approximately correspond with the dimensions of a document to be processed. 
     The curved guide means  61  is designed in such a way that a document ejected from the transport means  43  and dropped into the opening  62  is turned on its way by 180° as it is being transported up to the deposit magazine  41 . 
     The document support  42 , which is described in greater detail with the help of FIGS. 7 to  9 , is located on the side of deposit magazine  41  that is facing away from holding magazine  40 . Document support  42  substantially comprises a rectangular framework  63 , which is arranged on a transparent substrate  64  below which an illuminating device is arranged. The framework consists of hollow profiles, whereby the inner profile sides pointing at one another are slanted, so that a funnel-like structure is obtained which serves the purpose of self-centering of the documents ejected by transport means  43 . The cavities  65  of the hollow profiles are communicatively connected with the atmosphere via the slot-like openings  76  located between the lower edge of the inner profile sides and substrate  64 . Cavities  65  can be evacuated by means of a suction device not shown. 
     On the rear side of the framework  63 , a glass panel  68  is arranged on a rotary bearing  66  by means of the U-shaped cantilevered arms  67  and secured on the front end of the cantilevered arms. 
     On one of the cantilevered arms, provision is made for a lug  69  against which a pin  71  secured on the shaft of an electric motor  70  can be driven, so that the glass panel  68  can be pivoted from a covering position (the glass panel is positioned within the framework on the document positioned underneath it—see FIG. 9) up into the position shown in FIG.  8 . 
     FIG. 8 shows the situation in which the transport means  43  with a document clinging to it by suction has been driven into the position above the document holder  42 . FIG. 8 also shows that the hollow profiles serve at the same time as guide rails for the wheels of the transport means  43 . 
     The glass panel  68  is preferably secured on the cantilevered arm  67  by means of ribbons which are adhesive on both sides. The adhesive ribbon is elastic and acts as an additional bearing permitting a lesser amount of angular play. In this way, and also due to adequate tolerance in the bearings (bearing and shaft of the geared motor), the glass panel is provided with adequate clearance for flatly resting on the document in any case. 
     FIG. 9 shows that the cantilevered arms  67  are connected with each other by means of one or also two crossties. 
     The operational sequence of this device is described as follows: 
     A stack (not shown) of documents to be processed, for example digitized such as microfiches or microfilm jackets is contained in the holding magazine  40 . The transport means  43  is driven on top of the holding magazine  40  as shown in FIGS. 4 and 5. The glass panel  68  is located in the position shown in FIG.  8 . 
     Suction blower  56  is now started. This causes a document to be removed by suction from holding magazine  40  and to be attached to bottom plate  53  of housing  49 , whereby such document closes suction openings  54 . This actuates a microswitch  73  located in bottom plate  53 , which triggers a signal by which suction blower  59  is started. Suction blower  59  evacuates housing  44 , whereby the remaining stack is retained in holding magazine  40  due to slot-like openings  46  in the side walls of the holding magazine, and due to the gap present between transport means  43  and holding magazine  40 . This assures that only one document will adhere to transport means  43 . 
     However, it is possible also to dispense with microswitch  73  and to make provision instead for a microswitch  74  located in the flow path of the air blown by suction blower  56  through the openings  55  and  47 . Microswitch  74  is deflected by the flow of air against the force of a spring. Once a document has been picked up by suction, i.e. once suction openings  54  have been closed, the flow of air is interrupted and switch  74  pivots back into the starting position. This generates a signal that actuates suction blower  59  as well. 
     A third possibility is to make provision for a defined time factor defining a time span after which the transport means  43  starts to drive in the direction of the document holder  42  after the suction activity of the suction blower  56  has started. 
     The transport means  43 , with the document adhering to its underside, is driven across the housing  60  of the deposit magazine  41  until it is positioned directly above the document support  42  (see FIG.  8 ). The suction blower  56  is then shut off and the document drops into the document support  42 . 
     In the embodiment of the variation comprising the microswitch  73 , the spring force of the microswitch  73  serves for supporting said ejection movement. 
     Transport means  43  drives in the direction of housing  60  of deposit magazine  41 . The glass panel  68  is placed on the document. Now, the digitizing process takes place after the document has been optionally attached by suction to substrate  64  due to the evacuation of cavities  65  of framework  63 . After the digitizing process has been completed, glass panel  68  pivots again upwards, whereby the document remains attached to substrate  64  due to the still-prevailing vacuum. The vacuum is subsequently cancelled; transport means  43  drives on top of document support  42 , picks up the digitized document by suction, and drives back and on top of housing  60  of deposit magazine  41 , and, after blower  56  has been shut off, drops the document through opening  52  and via guide  61  into deposit magazine  41 . Thereafter, transport means  43  drives again on top of holding magazine  40  and the operational sequence described above is repeated again.