Lead screw document transport

Abstract

An encoded document is transported from an input station past encoding and read stations on a carriage driven by a lead screw. The encoded document enters at the input station and engages a drive roller that positions the document on the supporting carriage held stationary during loading at the input station. After positioning of the document on the carriage a drive motor is energized to rotate a lead screw to drive the carriage past the encoding and read stations for reading encoded data or encoding the document as desired. A document that has been encoded and verified is returned to the input station by energizing the drive motor to reverse the direction of rotation of the lead screw to return the carriage to the input station where a deflector ramp lifts the card from the carriage into contact with the drive roller which now rotates to eject the card through the input station. For selected documents the carriage is moved from the input station to a capture station wherein a ramp also deflects the document from the carriage to engage a drive roller for removing the card into a capture bin. The carriage includes a supporting tray with a spring biased pressure roller aligned to engage an edge of an encoded document to bias the document into a guide track for accurate positioning at the read and encoding stations. The encoded document is also positioned on the tray by an arrangement of spring biased rollers that maintain the card in the plane of the support tray. As the carriage moves past the encoding and read stations, idler rollers engage the document for accurate positioning on the carriage tray for the encoding or reading operations.

Description

This invention relates to a document transport and more particularly to an encoded document transport wherein the document is accurately positioned for a reading or encoding operation on a movable carriage.

Heretofore, an encoded document, e.g., a credit card, was usually transported in a pinch roller or flat belt system during an operational sequence for reading or encloding data onto the document. Pinch roller transport mechanisms consisted of a complicated array of rollers that frictionally engage a document for transport through the system. Although such transport mechanisms provide adequate movement of a document not requiring accurate speed regulation, the uneven wear of the rollers and changes in the coefficient of friction between various rollers cause uneven speed or "jitter" of a document with the result of erroneous reading of encoded data and also ambiguous data encoding.

In addition to the pinch roller array, other document transport mechanisms utilize endless belt drives wherein a document is moved by a frictional engagement between two moving belts. Again, accurate speed regulation for errorless code reading and nonambiguous encoding was difficult to achieve. These systems also relied on frictional contact and further required the synchronized movement of each of the belts of the system.

Both the pinch roller and flat belt transport mechanisms utilize drive motors which tend to accentuate the problem of speed regulation. For example, previous transport mechanisms employed either a stepper motor or a hysteresis synchronous motor as a primary drive. Stepper motors fundamentally provide an interrupting type motion with delayed step changes in motor speed. An idiosyncrasy of the hysteresis synchronous motor is that it hunts for the desired synchronous speed such that the speed time curve presents a series of damp oscillations. The magnitude of the speed regulation problem with a hysteresis synchronous motor varies with load such that the greater the load the greater the speed oscillations.

Another critical requirement of document transport mechanisms is the horizontal positioning of the document with respect to the encoding and read stations. For accurate and repeatable reading and encoding of a document it must be held in a fixed horizontal position with respect to the encoding and read stations.

With regard to the overall operation of a document transport mechanism, heretofore such systems required continuous monitoring and control of internal operations from an external central controller. This resulted in unnecessary loading of the capability of the central controller with monitoring and control functions related to the internal transport operation.

A feature of the present invention is to provide a document transport wherein encoded data can be read and data encoded during the movement of the document. Although the document moves past the reading and encoding stations, it is maintained in a fixed horizontal position on a supporting tray that itself is movable. The speed of movement of the supporting tray is accurately controlled to provide accurate control of all reading and encoding operations. Thus, data may be read from a card with greater precision than heretofore possible and data may be accurately encoded onto a document at predetermined encoding positions.

Another feature of the present invention is to provide a document transport wherein the document is held in a fixed position on a carriage as it is moved past reading and encoding stations. The carriage is positively positioned at the reading and encoding stations by a drive mechanism that utilizes a reluctance synchronous motor that maintains a synchronous speed below the pull-out torque rating of the motor. This enables accurate speed regulation of the carriage and a positive movement thereof. The carriage may be moved forward and in a reverse direction with the same degree of positive movement and accuracy. Throughout this movement an encoded document is maintained stationary with respect to the moving carriage although movable past reading and encoding stations.

A still further feature of the present invention is to provide a document transport wherein the document is positioned with respect to a fixed reference guide on a movable carriage. The reference guide forms a track through which the document is moved on a movable carriage. The document is forceably positioned in the reference guide by a horizontal pressure exerted on one edge of the document. The document is further accurately positioned with respect to the reference guide by a downward directed force on the document during transport past reading and encoding stations. Although constrained by the reference guide, the document has sufficient freedom to be positioned by the encode and read stations during movement through these stations.

In accordance with one embodiment of the invention, apparatus for transporting an encoded document to and from reading and encoding stations includes a carriage for supporting the encoded document. This carriage is coupled to a drive screw to cause movement of the encoded document to and from the reading and encoding stations. A reversible motor is coupled to the drive screw to impart rotary motion thereto. At an input station there is provided a device for loading/unloading a document onto the carriage while it is held in a stationary position at the input station. The document is loaded on the carriage for movement by the drive screw past the reading and encoding stations. When the carriage returns to the input stations, the document engages a deflector to force the document in engagement with the loading/unloading device for discharging of the document from the carriage at the input station.

In accordance with another embodiment of the invention, there is provided apparatus for transporting an encoded document to and from encoding and reading stations wherein a guide is formed as a part of a transport frame. The encoded document is transported to and from the reading and encoding stations in the guide on a document carriage that has mounter thereto a pressure roller to engage a document edge. This pressure roller biases the document into the guide formed as part of the transport frame. A drive screw is coupled to the document carriage to cause movement thereof to and from the reading stations.

A more complete understanding of the invention and its advantages will be apparent from the specification and claims and from the accompanying drawings illustrative of the invention.

REFERRING TO THE DRAWINGS:

FIG. 1 is a left side view of a lead screw card transport for transporting encoded document to and from reading and encoding stations;

FIG. 2 is a top view of the card transport of FIG. 1 showing the relationship between a document carrying carriage and a read station displaced from a write station;

FIG. 3 is a front view of the card transport showing the input stations through which an encoded document is inserted into the transport;

FIG. 4 is a fragmentary view of the left side of the card transport of FIG. 1 highlighting the deflection ramp at an input station;

FIG. 4A is a fragmentary view of the deflection ramp of FIG. 4 highlighting a card throat detector;

FIG. 5 is a right side view of the card transport of FIG. 1 showing the belt drive arrangement for rotating drive rollers to position a document on the carriage and also to remove the document from the carriage;

FIG. 5A is an exploded view of a torsion pulley assembly at the card throat of the transport as shown in FIG. 5;

FIG. 6 is a cross-section of the document carriage of FIG. 1 mounted on a lead screw for movement between the input station and a displaced capture station;

FIG. 7 is a side view of the carriage as shown in FIG. 1;

FIG. 8 is an enlarged partial end view of the document carriage showing one of the pressure rollers for exerting a downward force on a document in the carriage;

FIG. 9 is an enlarged sectional view of the clutch drive mechanism for rotating the lead screw coupled to the document carriage of FIG. 1; and

FIG. 10 is a schematic of the card handler of the present invention illustrating the various document stations.

Referring to the figures, there is shown a card transport wherein the operating structure is supported on a transport frame 10 with a base plate 12 fastened thereto and a mounting base 14 attached to the base plate by means of position leveling springs 16 and 18. At the upper right hand corner of the transport frame 10 there is located an input station 19 including a throat assembly 20 having a passage 22 for guiding a document into the transport.

Before an encoded document can be entered into the transport mechanism through the throat assembly 20, a lock bolt 21 must be rotated to an open position by energizing a bolt solenoid 24 supported on a solenoid bracket 26 mounted to the frame 10. Attached to the armature of the bolt solenoid 24 by means of a roll pin 28 is a bolt lever 30 that is attached to one end of the lock bolt 21. A bolt lever 30 is biased by means of a bolt spring 32 to maintain the bolt into a closed position across the opening 22.

Referrring to FIG. 4A, immediately adjacent the lock bolt 21 is a switch actuator 33 pivotally mounted by means of a pin 35. A document engaging the cam of the switch actuator 33 as it is transported from the system rotates the actuator counterclockwise to activate the snap action switch 37. Actuating the switch 37 generates a switch closure signal to a central controller to indicate the removal of an encoded document by a user of the system.

An encoded document inserted into the transport through the throat assembly 20 next engages an input drive roller 34 mounted immediately behind the throat assembly. The input drive roller 34 is in contact with an idler roller 35 (FIG. 10) mounted immediately below the drive roller to form a pinch roller pair that frictionally engages an inserted encoded document to pull the document into a transport mechanism.

For the document transport to receive an encoded document, a document carriage 36 is positioned at the input station 19 such that a card engaged by the input drive roller 34 will be deposited onto a carriage tray 38 as part of the document carriage.

The document carriage 36 provides a support for an encoded document on the carriage tray 38 fastened to a carriage base 40 by means of buttonhead screws 42. The carriage base 40 includes a transverse passage 44 in which is secured a carriage nut 46 in a driving engagement with a lead screw 48. A carriage bushing 50 is also secured in the transverse passage 44 to stabilize movement of the carriage base 40.

In contact with the lead screw 48 as it moves through the carriage bushing 50 is an oil wick 52 for providing continuous lubrication to the lead screw. The oil wick 52 is biased against the lead screw 48 by means of a spring 54 in contact with a washer 56. The entire oil supply assembly is maintained in place by means of the carriage tray 38.

Opposite the oil wick 52 there is attached to the carriage base 40 a carriage slider 58 by means of a dowel pin 60. The carriage slider 58 moves in a track 62 as part of the transport frame 10 to maintain the carriage in the correct upright orientation as it moves along the lead screw 48.

Attached to the side of the carriage base 40 is a carriage bracket 64 that supports the pressure rollers for maintaining an encoded document in a given position on the carriage tray 38. A transverse force is applied to a document on the carriage tray 38 by means of a pressure roller 66 mounted on a shaft 68 having a longitudinal axis at right angles to the plane of a document on a carriage tray. Thus, the pressure roller 66 engages one edge of a document on the carriage tray 38 to force it against a side wall 71 of the transport frame 10. The pressure roller shaft 68 is mounted to rotate on a shaft 70 supported by the carriage bracket 64. A coil spring 72 is assembled on the shaft 70 and engages the pressure roller shaft 68 to bias the pressure roller 66 into a position against a document on the carriage tray 38.

Also supported by the carriage bracket 64 are pressure rollers 74-77. The pressure rollers 74 and 75 are rotatably mounted to a carriage pressure arm 78 fastened to the carriage bracket 64. Similarly, the pressure rollers 76 and 77 are rotatably mounted on a carriage pressure arm 80 also attached to the carriage bracket 64. Mounting shafts 73 and 79 for the pressure rollers 74 and 77, respectively, extend through the respective carriage pressure arms 78 and 80. These shaft extensions are in contact with a spring 82 that passes below the carriage pressure arms 78 and 80 and above the shaft extensions 73 and 79 for the pressure rollers 74 and 77. With this assembly, the carriage pressure arm 78 is biased to rotate counterclockwise about a supporting shaft 84 and the carriage pressure arm 80 is biased to rotate clockwise about a support shaft 86. The amount of rotation of each of the carriage pressure arms 78 and 80 is determined by a stop plate 88 (FIG. 8) and extending webs 90 and 92 as part of the arms 78 and 80, respectively. These extending webs 90 and 92 engage the stop plate 88 that is fastened to the carriage bracket 64. The amount of rotation allowed the carriage arms 78 and 80 is, however, sufficient to allow the pressure rollers 74 and 76 to maintain a document in position on the carriage tray 38.

To drive the carriage base 40 the lead screw 48 is mounted for rotation with the transport frame 10 by means of bearings 90-93. The bearings 90 and 91 are mounted within the transport frame 10 at the end of the lead screw 48 displaced from the input station 19. These bearings 90 and 91 are maintained in a spaced relationship by means of a spacer washer 94 and a retaining ring 96 on a shaft 98 extending from the lead screw 48. The retaining ring 96 maintains the relative position between the lead screw and the bearings 90 and 91.

At the input station end of the lead screw 48 the bearings 92 and 93 are mounted within the support frame 10 and maintained in a spaced relationship by means of a bearing spacer 100. These bearings 92 and 93 support a shaft 102 extending from the lead screw 48. A retaining ring 104 locates the bearing 92 within the transport frame 10. This locates the shaft 102 in the frame 10 through the bearing spacer 100, the bearing 93, a lead screw pulley 108 and a jam nut 112. The shaft 102 is biased into this location by a pressure applied by finger springs 95 and 97 against the bearing 93 and also in engagement with the retaining ring 106.

Coupled to the shaft 102 by means of a woodruff key 110 and a jam nut 112 is the lead screw pulley 108. The lead screw pulley 108 has a crowned surface to be engaged by a flat belt 114. Power for driving the flat belt 114 is provided by a reversible reluctance synchronous motor 116 mounted to the transport frame 10 and coupled to a clutch mechanism 118.

As shown in FIG. 9, the motor 116 is coupled to the clutch mechanism 118 by means of a coupling 120 pinned or otherwise secured to the output shaft 122 of the motor and a clutch shaft 124. The clutch shaft 124 is supported in a clutch housing 126 by means of bearings, such as the bearing 128. Also supporting the clutch shaft 124 is a stationary clutch member 130 including an energizing coil (not shown).

Rotatably mounted on the clutch shaft 124 by means of bearings 132 and 134 is a drive pulley 136 also having a crowned surface for engaging the flat belt 114. Secured to the drive pulley 136 is a clutch disc 138 for engaging the clutch plate 131.

Rotary motion provided by the drive motor 116 is coupled to the drive pulley 136 by actuating the clutch member 130. This causes the clutch disc 138 to engage an energizing coil in the clutch plate 131 to drivingly connect the clutch shaft 124 to the output shaft 122 of the motor 116 to the flat belt 114. Rotary motion of the clutch shaft 124 is transferred through the lead screw pulley 108 to the lead screw 48. Since the carriage base 40 is restrained from rotating by means of the carriage slider 58, rotation of the lead screw 48 causes the document carriage to be moved from the input station 19 at the throat assembly 20 to a capture station 160 including a card capture tray 140.

To stop the document carriage 36 at a specific location along the lead screw 48, a lead screw brake 142 is coupled to the shaft 98 and attached to the transport frame 10. This brake is actuated to lock the lead screw 48 in a given position upon deactuation of the clutch member 130.

As a document is positioned on the carriage tray 38 by the drive roller 34, it is guided into place by means of card guides 144 and 146 fastened to the side wall 70. Additional card guides 148-151 are also provided on the side wall 70 to form a guide track for an encoded document on the carriage tray 38. An encoded document is biased into the guide track formed by the card guides 144, 146 and 148-151 by the pressure roller 66 exerting a force on the edge of the encoded document.

Spaced along the guide track provided by the card guides 144, 146, and 148-151 is an encoding station for encoding data onto a passing document and a read station for reading encoded data from a passing document. The encoding station includes a write head 152 positioned below the guide track and the read station includes a read head 154 (partially shown) also positioned below the guide track. Rotatably mounted above the write head 152 is a pressure roller 156 mounted to the side wall 70 of the transport frame 10. Similarly, immediately above the read head 154 is a pressure roller 158 also mounted to the wall 70.

For a few selected operations of the card transport, an encoded document on the carriage tray 38 is delivered to the card capture tray 140. The document carriage 36 is driven to the capture station 160 and stopped. As the carriage tray 38 approaches the capture station 160, an encoded document is deflected upward by a capture ramp 162 to be gripped between a pinch roller pair including a drive roller 164 and an idler roller 204 (FIG. 10) mounted immediately below the drive roller 164. The drive roller is driven to engage an encoded document deflected from the tray 38 and by frictional engagement removes the document from the tray for delivery into the card capture tray 140.

Referring specifically to FIGS. 2, 3 and 5, there is shown a belt and pulley arrangement for powering the drive rollers 34 and 164. An input/output motor assembly 166 is mounted to the transport frame 10 and includes a drive pulley 168 mounted to an output shaft 169. Encircling the pulley 168 is a timing belt 170 for providing power to the drive rollers 34 and 164. Mounted to the transport frame 10 immediately above the motor assembly 166 is a belt idler 172 to establish a path for the timing belt 170. The timing belt 170 also engages a timing belt torsion pulley assembly 174 mounted to a shaft 176 that extends through the wall 70 to the drive roller 34.

Referring to FIG. 5A, there is shown an exploded view of the timing belt torsion pulley assembly 174 including a timing pulley 174a freely rotating on the shaft 176. Formed as an integral part of the pulley 174a and extending from a surface thereof is a stop lock 174b. This stop lock 174b engages a stop pin 174c extending from an end plate 174d. The end plate 174d is affixed to the shaft 176 by means of set screws 174e. A roller spring 174f has one end engaging the pulley 174a and a second end engaging the end plate 174d. This spring biases the stop pin 174c against the stop lock 174b for normal operation, as shown in FIG. 5.

Functionally, the torsion pulley assembly 174 minimizes damage to a document transported through the drive rollers 34 and 35 onto the carriage tray 38. As the document is transported into the system through the drive rollers 34 and 35 the leading edge actuates a sensor 194 thereby causing the clutch member 130 to engage and cause rotation of the lead screw 48 and consequent movement of the carriage tray 38. Due to inherent delays within the mechanical and electrical operation of the system, the carriage tray 38 does not begin to move immediately upon sensing of the leading edge of a document. Thus, the document may be forced against the tray tab 41 on the carriage tray 38 before the carriage has started its movement and while the card is still engaged by the drive rollers 34 and 35. This presents a potential problem of damaging the inserted document or other malfunctions.

The torsion pulley assembly 174 permits the drive pulley 174a to rotate up to approximately 300.degree. after the document has been fully delivered to the carriage tray 38. As a document is delivered to the carriage tray 38 and hits the tray tab 41 the drive rollers 34 and 35 will stop rotating and the roller spring 174f begins to wind up by continued movement of the drive pulley 174a. The torque generated by the roller spring 174f is sufficient to deliver a document into the carriage tray 38 and the roller spring 174f will not begin to wind up until a card hits the tray tab 41.

The power train from the input/output motor assembly 166 next includes a timing belt pulley 178 mounted to a shaft 180 that extends through the wall 70 to support the drive roller 164. The input/output motor assembly 166 is reversible to provide selective directional rotation to the drive rollers 34 and 164.

Also attached to the transport frame 10 is an electronic cage 182 that includes electronic circuitry for controlling operation of the document transport. Input connectors 184 and 186 are provided for the circuitry within the electronic cage 182. Also connected to the electronic circuitry is an array of position sensors 188-191 displaced along the bed 192 of the transport frame 10. Another input signal to the circuitry in the electronic cage 182 is provided by a position sensor 194 mounted to the wall 71.

Operationally, the document transport of the present invention may be understood with reference to the schematic illustration of FIG. 10. To begin the transport operation the carriage 36 is at the front limit position 208 and an encoded document is inserted into the system through the throat assembly 20. As the inserted document passes a throat detector head 196 a signal is provided to external control circuitry that generates a command to the electronic cage 182 to actuate the input/output motor assembly 166, the drive rollers 34 and 164, and the lead screw motor 116. The card is gripped between the drive roller 34 and the idler roller 35 and delivered to the carriage tray 38 to be positioned in the plane of the tray by means of the pressure rollers 74-77, and further positioned in the guide track by the pressure roller 66. When the card has been positioned on the carriage tray 38, the sensor 194 provides a signal to circuitry of the electronic cage 182 to energize the clutch member 130 after releasing the lead screw brake 142. The clutch member 130 is not energized, however, until after the lead screw motor 116 has had time to achieve synchronous operation. This causes the lead screw 48 to be rotated to drive the document carriage 36 from the input station 19 first to the write head 152.

As an example of the sequence of operation in response to a read command from external circuitry, a document deposited on the carriage tray 38 is first transported past the inactive encode station, then to the read station including the read head 154 to enable the reading of encoded data on the document. As the document carriage 36 approaches the read head 154, the read sensor 189 responds to the sensor tab 200 to enable external circuitry, thereby initiating the reading of encoded data from the document. Also at the read head 154 a document on the carriage tray 38 engages the pressure roller 158 to accurately position the document on the tray by forcing the trailing edge thereof against a tray tab 39. Data is read from the document as it moves with respect to the read head 154, thereby providing a continuous flow of data to control circuitry not forming a part of the present invention.

After the document carriage 36 transports the encoded document past the read head 154, the carriage position is sensed by the rear sensor 188. In the usual mode of operation, the leading (rear) edge of the sensor tab 200 generates a signal from this sensor to the electronic circuitry of the cage 182 thereby deactivating the clutch member 130, applying the brake 142, and reversing the direction of rotation of the motors 116 and 166. Under automatic control of the system, the clutch member 130 is again energized, the brake 142 is released, and the lead screw 48 is driven in the reverse direction to drive the document carriage 36 to the front stop position 207, sensed by the leading (front) edge of the sensor tab 201 thereby activating the front sensor. The carriage 36 is again stopped and the motor reversed.

In response to a write-verify command from external circuitry, the carriage 36 is started forward as before by energizing the clutch member 130. When the start write sensor 190 detects the sensor tab 200, the encoded document on the carriage tray 38 is in the correct position for re-encoding data thereon. A signal from the write sensor 190 then enables external circuitry which supplies write data to begin the encoding sequence. As the document carriage 36 approaches the write head 152, the pressure roller 156 engages the leading edge of the encoded document and causes it to be positioned against the tray tab 39. Again, the document is accurately positioned on the carriage tray before beginning the encoding sequence.

As the sensor tab 200 passes the read sensor 189 a signal is provided to the circuitry for de-energizing the write head 152 to initiate the reading of the newly encoded data. The document carriage 36 continues to the rear stop position 206 and automatically reverse direction.

After verifying correct encoded data, external circuitry generates a return command, and the document carriage 36 continues toward the input station where an encoded document on the carriage tray 38 is deflected upward by a return ramp 202 to be gripped by the drive roller 34 and the idler roller 198. A signal generated by the front edge of the sensor tab 200 activating the front sensor 191 stops the carriage at the front limit position 208; meanwhile the input/output motor 166 rotates in a direction to drive the roller 34 to grip the encoded document deflected from the carriage tray 38. The document is delivered through the throat assembly 20 and out of the transport mechanism. As the card is removed from the throat assembly 20 the detector head 196 provides a signal to the electronic circuitry for shutting down the card transport.

For those conditions when an encoded document on the carriage tray 38 is to be delivered into the capture tray 140, external circuitry generates a capture command and the carriage is moved by the lead screw 48 past the read head 154 to the rear limit position 205. The rear sensor 188 allows the carriage to be driven to its extreme end position until detected by the sensor tab 201. As the carriage 36 approaches the card capture tray 140, the encoded document is deflected upward by the capture ramp 162. Previously, the input/output motor 166 was energized to cause rotation of the drive roller 164. A document deflected by the capture ramp 162 is gripped between the drive roller 164 and the idler roller 204 to be delivered into the card capture tray 140.

After a predetermined time interval, the motors 116 and 166 are reversed and the clutch member 130 actuated to impart rotation to the lead screw 48 in a direction to drive the document carriage 36 back to the input station 19. Again, When the document carriage 36 reaches the front limit position 208 the front sensor 191 provides a signal to de-energize the motors 116 and 166, activate the brake 142, and deactivate the clutch member 130. The document transport is again shut down and ready for a subsequent operational sequence.

While only one embodiment of the invention, together with modifications thereof, has been described in detail herein and shown in the accompanying drawings, it will be evident that various further modifications are possible without departing from the scope of the invention.

Claims

What is claimed is:

1. Apparatus for transporting an encoded document to and from reading and encoding stations, comprising in combination:

a document carriage for carrying the encoded document to and from the reading and encoding stations;

pressure rollers rotatably mounted to said carriage to position the encoded document in an established plane relative to the reading stations and encoding stations;

a drive screw coupled to said document carriage to cause movement thereof to and from the stations;

a reversible drive coupled to said drive screw to impart rotary motion thereto;

means at an input station for loading/unloading a document on said carriage;

means for positioning the document on said carriage during movement thereof; and

means for deflecting the document from said carriage to engage said means for loading/unloading to discharge the document from the carriage at the input station.

2. Apparatus for transporting an encoded document as set forth in claim 1 including a capture station displaced from the input station and further including means at the capture station for unloading an encoded document from said carriage.

3. Apparatus for transporting an encoded document as set forth in claim 2 wherein said means at the capture station includes:

means for deflecting the document from the carriage; and

means for engaging the deflected document to be discharged from said carriage at the capture station.

4. Apparatus for transporting an encoded document as set forth in claim 3 wherein said means for engaging includes a rotating drive roller frictionally gripping the deflected document.

5. Apparatus for transporting an encoded document as set forth in claim 1 including means in proximity to said reading and encoding station to position the encoded document on said carriage during movement thereof to and from said stations.

6. Apparatus for transporting an encoded document as set forth in claim 1 wherein said means for deflecting the document at the input station includes a ramp for forcing the document from said carriage into said means at the input station for loading/unloading.

7. Apparatus for transporting an encoded document as set forth in claim 6 wherein said means at the input station for loading/unloading includes a rotating drive roller frictionally gripping the deflected document.

8. Apparatus for transporting an encoded document to and from reading and encoding stations, comprising in combination:

a transport frame;

a guide as a part of said transport frame;

a document carriage for carrying the encoded documents to and from the reading and encoding stations in said guide;

pressure rollers rotatably mounted to said carriage to position the encoded document in an established plane relative to the reading stations and encoding stations;

pressure means mounted on said document carriage to engage an edge of an encoded document to bias the document into said guide; and

drive means coupled to said document carriage to cause movement thereof to and from the reading stations.

9. Apparatus for transporting an encoded document as set forth in claim 8 wherein said document carriage includes a tray for supporting the encoded document in the plane of said tray and in said guide.

10. Apparatus for transporting an encoded document as set forth in claim 9 including means as a part of said frame and spaced along said guide to position the encoded document in said tray as said carriage moves to and from the reading and encoding stations.

11. Apparatus for transporting an encoded document as set forth in claim 8 including an input station at one end of said guide and further including means at the input station for loading/unloading a document onto said carriage.

12. Apparatus for transporting an encoded document as set forth in claim 11 including a capture station displaced from the input station at the opposite end of said guide and further including means for unloading an encoded document from said carriage at the capture station.

13. Apparatus for transporting an encoded document to and from reading and encoding stations, comprising in combination:

a transport frame;

a guide as a part of said transport frame;

a document carriage for carrying the encoded document to and from the reading and encoding stations in said guide;

a pressure roller mounted on said document carriage to engage an edge of an encoded document to bias the document into said guide;

a drive screw coupled to said document carriage to cause movement thereof to and from the reading stations;

a reversible drive coupled to said drive screw to impart rotary motion thereto;

means at an input station for loading/unloading a document on said carriage; and

means for deflecting the document from said carriage to engage said means for loading/unloading to discharge the document from the carriage at the input station.

14. Apparatus for transporting an encoded document as set forth in claim 13 including a capture station displaced from the input station and further including means for unloading an encoded document from said carriage at the capture station.

15. Apparatus for transporting an encoded document as set forth in claim 13 including means spaced along said guide to position the encoded document in said tray as said carriage moves to and from the reading and encoding stations.

16. Apparatus for transporting an encoded document as set forth in claim 13 wherein said document carriage includes a tray for supporting the encoded document in the plane of said tray and in said guide.

17. Apparatus for transporting an encoded document as set forth in claim 16 including means mounted on said carriage to position the encoded document in the plane of said tray.

18. Apparatus for transporting an encoded document as set forth in claim 17 wherein said means mounted on said carriage includes a plurality of pressure rollers biased to hold the encoded document in said tray.

19. Apparatus for transporting an encoded document as set forth in claim 16 including a capture station displaced from the input station at one end of said guide and further including:

means for deflecting the document from said tray; and

means for engaging the deflected document to be discharged from said tray at the capture station.

20. Apparatus for transporting an encoded document as set forth in claim 19 wherein said means at the input station for loading/unloading and said means for engaging at the capture station each comprise a rotating drive roller frictionally gripping the deflected document.