US3630615A

US3630615A - Method and apparatus for transporting support material

Info

Publication number: US3630615A
Application number: US844530A
Authority: US
Inventors: John M Reynard
Original assignee: Xerox Corp
Current assignee: Xerox Corp
Priority date: 1969-07-24
Filing date: 1969-07-24
Publication date: 1971-12-28
Anticipated expiration: 1988-12-28

Abstract

Method and apparatus for transporting materials into contact with a member with which the material interacts. A cable drive moves a belt on a carriage holding the materials so that the materials have no relative motion with the work member they contact while in contact. The cable drive operates to rapidly index the belt to ready new material for contact with the work member and to more easily remove contacted material. An embodiment is used for transferring photoelectrophoretic images to support material by a transport capable of presenting the support material in rolling contact with the image to be transferred with suitable field conditions.

Description

United States Patent [72] Inventor John M. Reynard 3,464,818 9/1969 Waly 355/3 X A l N m gg Primary Examiner-Samuel S. Matthews [2!] i 1969 Assistant Examiner-Richard L. Moses [22] F Q J ly Attorneys-James J. Ralabate, David G. Petre and Barry J. [45] Patented Dec. 28, 1971 Kesselman [73] Assignee Xerox Corporation Roebeeter,N.Y.

ABSTRACT: Method and apparatus for transporting materials into contact with a member with which the material in- METHOD AND APPAAEATUS FOR TRANSPORTING teracts. A cable drive moves a belt on a carriage holding the SUPPORT MATE" materials so that the materials have no relative motion with the work member they contact while in contact. The cable [52] US. 35513, drive operates to rapidly index the belt to ready new material 355/ 16 for contact with the work member and to more easily remove [51] gfl G03 15/00 contacted material. An embodiment is used for transferring [50] l ieldolsearch 355/3, 16 photoelectrophoretic images to support material by a transport capable of presenting the support material in rolling con- 1 Ram CM tact with the image to be transferred with suitable field condi- UNITED STATES PATENTS tions.

2,990,278 6/1961 Carlson 355/3 X PATENTED m2 8 l97| SHEET 3 BF 3 METHOD AND APPARATUS FOR TRANSPORTING SUPPORT MATERIAL This invention relates in general to transporting and more particularly to transporting flexible materials for contacting work stations.

An illustrative system improved'by this invention is of the type using photosensitive radiant energy-absorbing particles believed to bear a charge when suspended in a nonconductive liquid carrier. The suspension of these particles in the carrier is placed in an electroded system to be exposed to an image radiation configuration. For a detailed description of the operation of this system, see U.s. Pat. Nos. 3,384,565 in the names of V. Tulagin and L. M. Carreira; 3,384,566 to H. E. Clark; and 3,383,993 to S. Yea, all issued on May 2], I968. The particles inthis system migrate in image configuration providing a visual image at one or both of the electrodes between which they are placed. The system employs particles which are photosensitiveand which apparently undergo a net charge alteration upon exposure to activating radiation by interaction with one of the electrodes. Various mixtures of two or more different colored particles can be used to secure various colors of images and imaging mixes having different spectral responses. These colors can be.used independently or even in subtractive color synthesis. In a monochromatic system, the particles will migrate-if energy of any, wavelength within the panchromatic spectrum of the particle response strikes the particle. l g

It has been found that images produced by the system broadly described are of excellent quality in both monochromatic and polychromatic systems. However, it is frequently undesirable to merely produce-an image on an electrode. Thus, for example, when a high-quality optical reusable electrode is employed, the use of a new electrode each time the imaging process is carried out might make the process prohibitively expensive and unsuitable for many applications. Therefore, it has been found better to transfer the image formed on one of the electrodes of the system to a flexible support material such as paper, cellophane, or the like. This transfer or support material may have an adhesive coating thereon to help draw the image off the image bearing member or may merely be bond paper or other materials that, when placed adjacent to the image bearing member under suitable conditions of electric field will draw the image from the member to its surface. A problem, especially in automated machinery, is to automatically bring the support material into contact with the image bearing member for transfer of the image to the support material. The invention herein is a system to bring various support materials into transfer contact with the image bearing member where, by suitable transfer techniques, the image can be stripped from the contacted member onto the support material and the support material easily removed from the apparatus while a second support material sheet is positioned for presentation to the image bearing electrode when a transfer of the image is again required in the machine cycle.

Another use for the system is to transport sheets or the like for transfer or fusing within a xerographic apparatus.

Therefore, it is an object of this invention to improve transfer of electrophoretic imaging systems by providing practical means for automating the transfer of images to support materials. Another object of this invention is to provide means for presenting support material to image bearing members and removing the support material after transfer of an image thereto.

Yet another object is to transport support material into and out of close proximity with a contact member and then automatically present unused support material for transport past the member.

The foregoing objects and others are accomplished in accordance with this invention by introducing a driven transport apparatus having a double movement system providing for traversing a member with a carriage. The carriage maintains a I support material to be brought into close proximity and in nonmoving contact with the member. After completion of the traverse, the carriage of the transport maintaining the support material is indexed to provide a new support material surface for interaction with the member. Further objects of the present invention are accomplished in relation to photoelectrophoretic image transfer and xerographic image transfer by bringing a support material into close proximity with the formed image on the image bearing member of the imaging system and applying an electrical field across the zone of contact between the image bearing member and the support material at such a field direction as to transfer the image to the support material. Because of the broad contact area between the image bearing member and the support material, due to the physical arrangement of the transport system bringing the support material into contact with the image bearing member, a more complete transfer in photoelectrophoretic images can be achieved in a shorter period of time.

Any suitable technique may be employed for applying the electrical field for transfer including forming the support material maintaining structure with a conductive backing strip and an insulating sleeve. Any suitable technique may be employed for applying the electrical field behind the support material maintaining member such as applying a roller plate or other conductive element for connecting to a high potential source to the substrate or applying a high potential corona discharge to the back of the transfer substrate while it is in close proximity with the image. In the preferred form, the polarity of the applied field will be opposite to the polarity applied to the imaging member of the imaging system. Thus, if the imaging member is negatively charged the potential applied behind the transfer substrate will be positive in charge and vice versa.

The transport apparatus is also usable with an image fixing or fusing apparatus being the work station with which the transport operates to bring support material.

The transport system itself may maintain a support material to be used to transfer an image or may be formed of a material suitable for the purpose of transfer or any other purpose to which the transport is put. The transport is formed of a carriage that can be driven across a work station such as an image bearing member or the like while the support material maintained on the carriage is moved to be preferably in rolling contact with the work station as the carriage traverses in close proximity thereto. After passing the work station, the support material on the carriage is indexed by suitable drive. means that further serve to achieve the rolling contact motion during the traversing of the carriage past the work station. In a preferred embodiment, the mechanism is operated by a drive to pull the carriage across a path in close proximity to the work station and a cable or the like held fast during the,

traversing movement causes the necessary relative motion between the support member and the transport to allow rolling contact past the work station. The cable is then used to index the support material to a proper position for a return stroke of the carriage to once again move past the work station for another operation.

The advantages of this improved transport system particularly relative to transfer of image will become further apparent upon consideration of the following detailed disclosure of the invention; especially when taken in conjunction with the accompanying drawings wherein:

HO. 1 is a schematic side view of the transport system in conjunction with a xerographic imaging system;

FIG. 2 is a section taken along-line 2-2 of H6. 1;

FIG. 3 is a schematic isometric view of the transport system in the environment of a photoelectrophoretic imaging system, and

FIG. 4 is a schematic isometric view of the drive cable for the transport of FIG. 3.

Referring now to the Figures, FIG. 1 is a schematic representation of this invention in relation to a xerographic copying apparatus. The xerographic apparatus is schematically shown with a xerographic member or photoreceptor belt 10 mounted over three rollers 12, l4'and l6 at least one of which drives the belt with the others functioning as idler rollers. All are journaled for rotation to permit movement of the belt in the direction indicated by the arrow to cause the surface of the belt to sequentially pass a plurality of xerographic processing stations. For the purpose of the present disclosure, the several xerographic processing stations in the path of movement of the xerographic member may be described functionally as follows:

a charging station A at which a uniform electrostatic charge is deposited on the photoconductive layer of the xerographic member an exposure station located preferably as shown by reference character B at which a light or radiation pattern of copy is exposed onto the photoreceptive member to dissipate the charge on the exposed portions thereof forming a latent electrostatic image of the pattern of the object 18 illuminated by lamps 20 through a lens 22;

a developing station C whereat the latent electrostatic image is developed by cascading an electrostatic developer over the belt 10 forming a toner image corresponding to the latent electrostatic image on the belt;

an image transfer station D where the toner image is electrostatically transferred from the belt surface to a transfer material with the use of a corona discharge device 23; and

a cleaning station E where the belt is cleansed of residual toner and is discharged in order to prepare the belt surface for the next cycle.

At the transfer station is the carriage generally referred to as 24 which presents a sheet of support material, such as sheet 26, to the surface of the belt 10 for contact therewith to remove the toner image from the belt to the support material. The carriage 24 is moved laterally across the lower surface of the belt by any drive means such as a first drive means motor M-l, connected to a pulley 28 which moves the transport in the direction shown by the arrow through a cable or tape or the like designated 29 and clamped to the transport by clamps 3]. Friction reducing movement is provided by passing cable 29 through pulley rollers 33 and idler roller 35. The transport traverses the xerographic belt 10 with a transfer material 26 maintained between the two. The speed of the transport surface, being a belt or a sleeve 30, is exactly matched to the speed of the xerographic belt 10 so that the support material 26 will not smear the toner image on the belt 10 during the contact therewith. I

In order to accomplish this result and yet have the transport move back and forth across the belt presenting a different sheet to the xerographic belt 10 each time, it is necessary to provide the belt 30 with a velocity different from the transport member. Not only must this speed be different from the speed of the transport but it must be related to it and to the speed of the xerographic belt. Variable speeds can be built in to cause the belt 30 to move at different speeds on the movement of the transport from one side of the belt to the other. It is also required that the belt 30 be indexed to present a clean sheet of support material for transfer at the xerographic belt while permitting removal of a previously used sheet. lndexing" here means the moving of the belt 30 when out of contact with the work station (xerographic belt 10) while the carriage 24 is moving or stationary in order to bring the belt 30 around the carriage for easy removal of the used sheet and for setting a new sheet in position on the belt 30 to contact the work station as the carriage traverses it and the belt rotates.

Programmer means are incorporated into the structure of the transport system in order to achieve the results that follow. The belt member 30 is held on two

support rollers

32 and 34 maintained a predetermined distance apart by a rod 36 which through bearings connect with each of the support rollers. The rod 36 also fon'ns a runner which moves over the guide rail 38 giving support to the transport system and determining the path which will be traveled by the transport as it oscillates such as clamp 40 maintain the support material 26 at fixed positions on the belt 30 of the carriage 24. The rail 38 is suitably mounted to the frame of the machine. The motion given to the belt 30 around the

support rollers

32 and 34 of carriage 24 is provided by a chain drive although any drive connector means are usable. The motion of the rollers is determined by a chain 42 wrapped around an idler pulley 44 and a power pulley 46. The chain is wrapped completely around, and rests in suitable grooves 48, within, the transport belt 30. Alternatively, separate pulleys on the

support rollers

34 and 32 could be provided to engage the sprockets of the chain 42 to transmit the required motion to the belt 30. Although the chain is shown exaggeratedly below the transport, it is actually preferable to have the

pulleys

44 and 46 mounted so that the chain is parallel with the carriage 24. lf this were not the situation, a distance compensating mechanism must be established. An elastic member can be added to the drive chain 42 or an elastic cable can be used. This would require a motor speed control and feedback system to compensate speed variations with stretch. Obviously, this is a more complex system but the schematic illustrations used here point out the structure used and should not be regarded as to scale or as preferring a chain being nonparallel to the transport.

Motion to the chain is provided by a second drive means designated M-Z through a suitable gear box 50 through a shaft 51 to one of the chain pulleys 44 having means to engage the sprockets of the chain for nonslip movement of the chain thereover. The chain material can be standard metal chain, plastic chain, nylon or alternatively timing belts, friction belts or any other flexible means suitable for the required transmission of motion to the belt 30. i

The motor M-2 and the gear box 50 are capable of delivering at least two speeds to the chain 42 for moving the support surface 26 past the xerographic belt 10. Further, the gear box 50 or motor M-2 is capable of reversing the direction of movement of the chain 42. The surface velocities given to the belt 30 maintaining the transfer material 26 in the embodiments shown in FIGS. 1 and 2 are related to the constant velocity of the xerographic member 10 in the following relationship.

Assume that the surface velocity of the xerographic belt 10 is X inches per second in the direction indicated by the vertical arrow in FIG. 1 and assume that the velocity of the carriage 24 (consider the velocity of the connecting rod 36) is Y in the direction indicated by the two-headed arrow.

The velocity of the sheet 26 as well as the belt 30 is given a velocity 2Y (with respect to ground or a stationary observer standing at point 40 on the lower side of the belt 30 along a portion of the belt 30 under the sheet 26 as shown in FIG. 1 if the cable 42 were held fast). The motor M-2 and gear box 50 must subtract from 2Y enough to yield X with respect to ground.

Let the drive motor and gear box combination subtract a velocity equal to 2 from the system. Therefore:

In other words, the drive motor adds. 2Y-X in the opposite direction to the movement of the belt 30. Therefore the motor-gear box combination drives the sheet 26 X+2Y (X--( 2Y)) units in the opposite direction from the movement when both the belt 10 and the carriage move in the same direction. This relationship holds for either direction movement of the carriage and any velocity of the carriage and the contacting member such as belt 10 in FIG. 1 or the stationary member 60 in FIG. 3.

Depending on the absolute numerical values of X and Y it is possible that the surface velocity of the belt 30 will have to be in different directions as well as at different magnitudes when the movement of the carriage 24 is reversed across the belt 10. lf that is the situation, the gear ratio must permit the necessary change in magnitude of the velocities and provide a reversal in the direction of movement of the chain drive. Any suitable gearing apparatus known in the art is acceptable for the accomplishment of the required velocities for this invention. An alternative to separate gearing connections for achieving the velocities required is to provide a multispeed and/or reversable motor M-2 preset to achieve the desired velocity characteristics necessary to permit the support material 26 to pass across the surface of the xerographic belt in nonslip contact for the transfer of the toner image from the belt to the support material without the smudging thereof.

The carriage with the belt 30 wrapped therearound moves past the work station so that the belt 30 no longer contacts the xerographic belt 10, thereby preventing interference between the support material 26 on the belt 30 and the xerographie belt 10 at the work station. The chain is made to index so that the support material 26, which by this time is at the bottom side of the transport belt 30, is brought to the top for removal from the belt 30. This may be done while the carriage 24 is still moving or after it has come to rest.

To provide for continuous operation of the transport on the return stroke past the xerographic belt 10, just prior to the indexing motion by the chain 42 a separate sheet of support material 26 can be added to the top portion of the belt 30. Now when the belt 30 is indexed, not only is the sheet with the image on it brought to the top portion of the belt 30 but the clean sheet just placed on the belt 30 is moved into position for contacting the xerographic belt 10 when the transport moves along its return stroke past the belt 10. To index the belt 30 it is necessary for the chain 42 to pull the belt 30 around the

rollers

32 and 34 supporting the carriage. The carriage may be moving or stationary since the operation of indexing is superposed on the movement of the carriage 24 across the rail 38. An actuator means can be used for engaging motor M-2 the chain 42 moves along its path causing the belt 30 to turn. By energizing the motor M-2 for the proper period of time such as by rotation at a higher speed, the belt 30 rotates through a sufficient amount of travel to bring the image sheet 26 to a position for easy removal from the carriage as well as to bring a clean sheet, placed on the belt 30, to a predetermined position for later contact with the xerographic belt 10 upon the return stroke of the transport sleeve or belt 30 past the xerographic belt 10.

The embodiment shown in FIG. 3 relates to the use of a transport system in conjunction with a photoelectrophoretic imaging system. The photoelectrophoretic imaging system member 60 is an injecting electrode composed of a transparent glass substrate 62 and an overcoated electrical coating layer 64. The injecting electrode may have a layer of tin oxide coating on the glass which forms a composite that is commercially available under the name of NESA from Pittsburgh Plate Glass Co. Any other suitable structure usable with the electrophoretic imaging system as described in U.S. Pat. Nos. 3,383,993; 3,384,565 and 3,384,566 (the disclosures ofwhich are incorporated herein) is acceptable with this invention. Deposited on the electrical conducting layer 64 of the injecting electrode 60 is a thin layer of finely divided photosensitive particles dispersed in an insulating liquid carrier. This is the imaging suspension 66 from which a final image is formed.

The injecting electrode is schematically shown in two positions. The first (and dotted) is for inking and imaging and the second is for transferring. When the injecting electrode is in the first position, the suspension is deposited on the NESA surface from a suspension supply tank 67. After the suspension is applied to the electrode, a blocking electrode 68 contacts the injecting electrode 60. The blocking electrode has a layer of blocking material, that is, material which once contacted by photosensitive particles will not inject a charge into a sufficient number of them to cause a migration from the blocking electrode.

The term photosensitive" for the purposes of this invention refers to the properties of a particle which, once attracted to the injecting electrode, will migrate away from it under the influence of an applied electric field when exposed to sufficient activating electromagnetic radiation. The term suspension" may be defined as a system having solid particles dispersed in a solid, liquid or gas. Nevertheless, the suspension described in the embodiment herein is of the general type ineluding that having a solid suspended in a liquid carrier. The term "injecting electrode" refers to the electrode the properties of which apparently inject charges into photosensitive particles activated by electromagnetic radiation while under the influence of an electric filed. i

The photosensitive suspension 66 is subjected to electromagnetic radiation in image configuration by, for example, shining a light source 70through an object such as a transparency 71 which is imaged through a lens 72 to the photosensitive suspension 66 on the surface of the injecting electrode 60. More or less simultaneously with the projection of the object to the suspension, an electric field is applied between the electrodes 60 and 68. This is done by any suitable electrical energy source such as source 73 providing potential for a field between the blocking electrode and the grounded'NESA surface. The field can be in either direction although, as shown, the blocking electrode is negative relative to the NESA surface.

The mechanism functions such that when the activated blocking electrode 68 traverses the surface of the injecting electrode 60, an electric field is formed at the interface of the two electrodes. The particles within the suspension are nonconductive unless they are struck with activating radiation. Under the influence of the applied electric field the negative particles come into contact with or are closely adjacent to the injecting electrode 60 and remain there. When activating radiation strikes the photosensitive particles they, through the process described in the above-cited patents, migrate selectively from the injecting electrode leaving an image formed thereon for transfer to a suitable support member. The carriage 74 functions in a manner similar to that described in relation to the carriage 24 of FIG. 1. A differencehere is that the motor mechanisms are simplified since the transport traverses a stationary member rather than a moving xerographic belt. I Q

The sequencing of events for forming and transferring an image is as follows. When the apparatus is activated, the suspension is applied to the injecting electrode in its first position by suspension supply tank 67.Next to traverse the injecting electrode is the blocking electrode 68 which forms an image on the injecting electrode 60 suitable for transfer. Next, the injecting electrode with the optical system moves to the transfer position and the carriage 74 traverses the injecting electrode with the chain -76 held stationary during the movement of the carriage 74. This permits the lateral translation of the carriage 74 along the rails while providing for the turning of the sleeve 77 around the support rollers 78 and 79 and brace 80 maintaining the rollers. The surface movement of the sleeve 77 is such that it is directly opposite and equal in magnitude to the translation of the carriage 74 across the injecting electrode 60. Therefore, the support material maintained on the sleeve 77 contacts and is stripped away from the injecting electrode in a nonskid manner as the transport traverses the injecting electrode. During transfer the injecting electrode is illuminated in imagewise radiation and a field is maintained between the injecting electrode and the transfer transport. To aid in transfer of the image, a plate 81 is positioned behind the sleeve 77 of the transport and is biased positively by suitable electrical source 82.

The carriage 74 is moved out of contact with the injecting electrode and is indexed by the chain 76 moving a predetermined distance to bring the support material with the image thereon to the upper portion of the transport as viewed while moving a clean sheet placed on the transport to a predetermined ready position for contact with the injecting electrode on the return stroke of the transport. The indexing movement is achieved by a motor M-3 connected through a gear box 83 to one of the pulley sets 84 of the transport system by a shaft 85. The chain 76 is held in slots 86 within the sleeve 77. However, pulleys could be extended -from rollers 78 and 79 to maintain the chain for its function.

Before the return stroke, the injecting electrode is moved to the position to be inked with the imaging suspension by supply on the sleeve 77. This permits better use of the electrical field supplied by the connected plate 81.

The broad area of contact between the transfer sheet and the injecting electrode permit better transfer of the images than would be the case with a circular cylindrical roller traversing the electrode for the same period of time. Since the sleeve 77 of the carriage 74 is made up of a composite material having a conductive backing sheet and an insulating cover the electrical contact made by plate 8! permits a field to exist across the entire area of contact between the carriage 74 and the illuminated injecting electrode 60. This provides for the transfer of the image for the entire time of contact between any portions of the injecting electrode and the support material maintained on the carriage 74.

FIG. 4 shows the looping of the chain around the sleeve 77 of the transport system. The chain" may be composed of chain links, tape, cable, timing strips or the like and may be made of any material usually employed for such a device.

As for the sequencing of events on the transport itself, there is a movement of the entire transport along the rail supporting it at a constant velocity until the transport is past the work station with which it is to be engaged. After passing the work station and either while still moving or after coming to rest a second sheet of unused support material is positioned at a predetermined portion of the surface of the transport and the transport surface is indexed by movement of the chain drive in order to move the unused sheet to a predetermined position for later use at the work station on or during the return stroke of the transport. Simultaneously, the previously used support material that has already passed through the work station is moved to a position for removal from the transport. The chain drive will either remain stationary causing the surface of the transport to move at a predetermined velocity while the support material on it is at the work station in order to achieve relative nonmotion of the support material with the member working on it at the work station or the chain will be moved at a predetermined velocity in order to achieve relative nonmotion with the member contacted at the work station. Generally then, the system functions to permit nonslip movement of a support material at the workstation of the apparatus with which it is combined while providing means to remove used support material and supply unused support material at such positions along the surface of the transport to continually, if required, present clean support material at the work station while continually removing used support material from the transport.

While this invention has been described with reference to the structures disclosed herein and while certain theories have been expressed, it is not confined to the details set forth; and this application is intended to cover such modifications or changes as may come within the purposes of the improvement or the scope of the following claims.

What is claimed is:

l. A method of transporting support material past a work station including the steps of a. placing the support material on a portion of member of a moveable carriage,

b. indexing the support material relative to the carriage to a first predetermined position,

c. moving the carriage to traverse the work station,

d. simultaneously moving the support material relative to the carriage,

e. positioning the carriage to prevent interference between the support material and the work station. 2. The method of claim 1 wherein the steps of moving the carriage to traverse the work station and the simultaneous moving of the support material relative to the carriage occur such that the support material is moved in rolling contact with the work station.

3. The method of claim 1 further including the step of indexing the support material relative to the carriage after the completion ofsteps (a) through (e).

4. The method of claim 3 including removing the support material from the portion of the member of the carriage.

5. The method of claim 1 further including the step of placing more support material on another portion of the member of the carriage after the completion of steps (a) through (e).

6. The method of claim 5 further including the step of indexing the support material relative to the carriage after the step of placing more support material on the member of the carriage.

7. In an apparatus for forming transferable images having an image bearing member adapted to support the image formed, the improvement comprising means for transferring the image to a support material including a belt adapted to maintain the support material,

a carriage to support the belt,

first drive means to move said carriage relative to the image bearing member,

second drive means to rotate said belt relative to said carriage,

said second drive means being connected for rotating said belt relative to said image bearing member such that said belt and said image bearing member pass in rolling contact,

actuator means to activate said second drive means to index said belt a predetermined amount of revolutions.

8. Transport apparatus for moving flexible material relative to a work station including a carriage movable past the work station,

mounting means joumaled in said carriage and capable of rotational movement within said carriage,

a sleeve wrapped on said mounting means in nonslip contact, carriage drive means operatively connected to said carriage for moving said carriage relative to the work station,

second drive means operatively connected to said mounting means to rotate said mounting means and said sleeve within said carriage at a first rate and a second rate,

program means to activate said carriage drive means and said second drive means such that said second drive means rotates said sleeve at a first rate during movement of said carriage and at a second rate when said carriage is past the work station.

9. The apparatus of claim 8 wherein said first rate of rotation of said sleeve is related to the movement of said carriage such that there is a rolling contact presentation of the flexible material at the work station.

a: a: a: r n:

Claims

1. A method of transporting support material past a work station including the steps of a. placing the support material on a portion of member of a moveable carriage, b. indexing the support material relative to the carriage to a first predetermined position, c. moving the carriage to traverse the work station, d. simultaneously moving the support material relative to the carriage, e. positioning the carriage to prevent interference between the support material and the work station.

2. The method of claim 1 wherein the steps of moving the carriage to traverse the work station and the simultaneous moving of the support material relative to the carriage occur such that the support material is moved in rolling contact with the work station.

3. The method of claim 1 further including the step of indexing the support material relative to the carriage after the completion of steps (a) through (e).

7. In an apparatus for forming transferable images having an image bearing member adapted to support the image formed, the improvement comprising means for transferring the image to a supPort material including a belt adapted to maintain the support material, a carriage to support the belt, first drive means to move said carriage relative to the image bearing member, second drive means to rotate said belt relative to said carriage, said second drive means being connected for rotating said belt relative to said image bearing member such that said belt and said image bearing member pass in rolling contact, actuator means to activate said second drive means to index said belt a predetermined amount of revolutions.

8. Transport apparatus for moving flexible material relative to a work station including a carriage movable past the work station, mounting means journaled in said carriage and capable of rotational movement within said carriage, a sleeve wrapped on said mounting means in nonslip contact, carriage drive means operatively connected to said carriage for moving said carriage relative to the work station, second drive means operatively connected to said mounting means to rotate said mounting means and said sleeve within said carriage at a first rate and a second rate, program means to activate said carriage drive means and said second drive means such that said second drive means rotates said sleeve at a first rate during movement of said carriage and at a second rate when said carriage is past the work station.