The invention relates to electrostatography and to electrostatographic roller apparatus, and in particular to a fixture and method for use to remove and replace an inner sleeve member of a double-sleeved roller.
Usage of compliant rollers in electrophotographic apparatus is well known, which compliant rollers may incorporate a removable sleeve member mounted concentrically around a mandrel. Single-sleeved and double-sleeved compliant rollers have been disclosed, e.g., sleeved imaging rollers, sleeved intermediate transfer rollers, and sleeved rollers for use in a fusing station. In an electrostatographic machine, a toner image can be formed on a sleeved imaging roller, transferred in a first transfer operation from the imaging roller to a sleeved intermediate transfer roller, and subsequently transferred in a second transfer operation from the intermediate transfer roller to a receiver member (e.g., paper). The toner image on the receiver member is subsequently fixed thereon in a fusing station.
The use of a removable endless belt or tubular type of blanket on an intermediate transfer roller has long been practiced in the offset lithographic printing industry. As disclosed, for example, in the Julian patent (U.S. Pat. No. 4,144,812) an intermediate lithographic roller has a portion having a slightly smaller diameter than the main body of the roller, such that a blanket member may be slid along this narrower portion until it reaches a location where a set of holes located in the roller allow a fluid under pressure, e.g., pressurized air, to pass through the holes, thereby stretching the blanket member and allowing the entire blanket member to be slid onto the main body of the roller. After the blanket is located in a suitable position, the source of pressurized air or fluid under pressure is turned off, thereby allowing the blanket member to relax to a condition of smaller strain, such strain being sufficient to cause the blanket member to snugly embrace the roller. The Gelinas patent (U.S. Pat. No. 5,894,796) discloses that the tubular blanket may be made of materials including rubbers and plastics and may be reinforced by an inner layer of aluminum or other metal.
An intermediate transfer roller having a rigid core and a removable, replaceable intermediate transfer blanket has been disclosed by Landa, et al., in U.S. Pat. No. 5,335,054, and by Gazit, et al., in U.S. Pat. No. 5,745,829, whereby the intermediate transfer blanket is fixedly and replaceably secured and attached to the core. The intermediate transfer blanket includes a substantially rectangular sheet mechanically held to the core by grippers. The core (or drum) has recesses where the grippers are located. It is disadvantageous that the entire circumference of the intermediate transfer drum cannot be utilized for transfer because the blanket does not form a continuous covering of the core surface. Moreover, particulate contamination tends to collect in the unavoidable gap between the ends of the blanket.
An electrostatographic imaging member in the form of a removable replaceable endless imaging belt on a rigid roller is disclosed by the Yu, et al. patent (U.S. Pat. No. 5,415,961). The electrostatographic imaging member is placed on the rigid roller and removed from the rigid roller by stretching the endless imaging belt with a pressurized fluid.
The Mammino, et al. patents (U.S. Pat. Nos. 5,298,956 and 5,409,557) disclose a reinforced seamless intermediate transfer member that may be in the shape of a belt, sleeve, tube or roll and including a reinforcing member in an endless configuration having filler material and electrical property regulating material on, around or embedded in the reinforcing member.
The Chowdry, et al. patent (U.S. Pat. No. 6,605,399) discloses a sleeved compliant primary image-forming roller and a method of making such a roller. The sleeve is a photoconductive member, the sleeve resting on a compliant layer coated on a core member. This has certain advantages over U.S. Pat. No. 5,715,505 and U.S. Pat. No. 5,828,931, in that the coatings on the roller are made more reliably and more cheaply, and also in that the photoconductive sleeve may be readily removed and replaced when at the end of its useful life, thereby lowering cost and reducing downtime. The Chowdry, et al. patent (U.S. Pat. No. 6,605,399) also includes an advantage over U.S. Pat. No. 5,415,961 by providing a core member coated by a thick compliant layer over which the sleeve member is placeable and removable. However, in certain embodiments of this Chowdry, et al. patent, the rigid core member is electrically biased to effect transfer of toner, and because the electrical properties of the compliant layer coated on the core member alter with age, the compliant layer has a finite lifetime requiring expensive periodic replacement of the coated core member. Moreover, the compliant layer is disadvantageously subject to damage when removing or replacing a sleeve member, and such damage may necessitate recoating or replacing the costly core member.
The Shifley, et al. patents (U.S. Pat. Nos. 6,259,873, 6,263,177 and 6,484,002) disclose apparatus including a roller (such as a photoconductive roller or an intermediate transfer roller) which roller has a removable replaceable surface or sleeve, and which roller is supported at one end in cantilevered fashion during sleeve removal or replacement via the other end of the roller. For operation of the roller, the roller is supported at both ends. A disconnectable supportive member is provided that can be disengaged and moved away from the roller so as to provide a free end for purpose of sleeve removal or replacement. This supportive member is moved back so as to engage and support the roller for operation.
The Cormier, et al. patent (U.S. Pat. No. 6,394,943) describes an image transfer drum inclusive of a mandrel having an air bearing to facilitate loading and removal of a resilient sleeve. The air bearing is provided with a pair of cooperating plates one of which is scored with equally spaced and radially extending grooves. When urged together, the plates define a central air chamber and a plurality of radially-extending passages serving to direct pressurized air radially from one end of the mandrel, at which end the sleeve can be removed and replaced. The pressurized air is conveyed to the central chamber via a pipe passing into the mandrel at the other end of the mandrel, at which other end the mandrel is supported in cantilever fashion during removal or replacement of a sleeve.
Advantage over the Chowdry, et al. patent (U.S. Pat. No. 6,605,399) and the Cormier, et al. patent (U.S. Pat. No. 6,394,943) is obtained by providing an electrostatographic double-sleeved roller, as disclosed in the Chowdry, et al. patent (U.S. Pat. No. 6,377,772). Such a type of double-sleeved roller (DSR) can be useful for a number of applications in an electrostatographic machine, for example as a primary image-forming member or as an intermediate transfer member. The DSR includes a cylindrical rigid core member, a replaceable removable multilayer inner sleeve member (ISM) in the shape of an endless tubular belt including at least one compliant layer (e.g., made of a polyurethane) such that the ISM surrounds and nonadhesively intimately contacts the core member, and a replaceable removable multilayer outer sleeve member (OSM) in the shape of an endless tubular belt including at least one synthetic layer such that the OSM surrounds and nonadhesively intimately contacts the ISM. The synthetic layer may include, for example, a plastic, a polymer, a copolymer, an elastomer, a foam, a photoconductive material, a material having filler particles, a material including two or more phases, or a material reinforced with fibers. Because of the double-sleeve construction, an accurately dimensioned core member can have a long life without need of replacement. Moreover, the core member can advantageously remain fixed to the electrostatographic apparatus in which it is mounted when a sleeve member is replaced, and in a preferred embodiment either or both OSM and ISM are removable from the same end of the roller. A DSR as disclosed in the Chowdry, et al. patent (U.S. Pat. No. 6,377,772) has an extra advantage in that a stiffening layer can be included as an exterior outer surface of an ISM or more preferably as an exterior inner surface of an OSM, thereby avoiding certain coating complications and facilitating mounting and demounting of the sleeves. Additionally, overall operating costs are reduced, inasmuch as either sleeve may be replaced without replacing the other, or else the inner and outer sleeves may be replaced with differing frequencies. Thus an inner or outer sleeve member can easily and independently be replaced on account of wear or damage, or replaced when at the end of a predetermined operational life. An expensive, finely toleranced core member can thereby be retained for long operational usage with many generations of sleeve members.
The Aslam, et al. patents (U.S. Pat. Nos. 6,393,249 and 6,567,641) disclose double-sleeved rollers for use in a fusing station of an electrostatographic machine, e.g., as fuser rollers, as pressure rollers, or both.
An inner sleeve member (ISM) employed according to the Chowdry, et al. patent (U.S. Pat. No. 6,377,772) includes a flexible high-modulus tubular band, e.g., as a strengthening band or backing layer concentric with and supporting an adhered compliant layer. With the outer sleeve member (OSM) removed, this backing layer facilitates handling of the ISM during its removal or replacement using a pressurized air technique akin to that disclosed in the Julian patent (U.S. Pat. No. 4,144,812). However, to manufacture such a reinforced ISM generally requires a costly coating process. Thus there is a need to reduce manufacturing expense. One solution is to utilize a relatively cheap, non-reinforced, compliant ISM, i.e., an ISM having no high-modulus band or backing layer, such as is disclosed below for inclusion in the present invention. However, a non-reinforced relatively stretchable ISM (not contemplated in the Chowdry, et al. patent (U.S. Pat. No. 6,377,772)) has a propensity to exhibit edge disturbance when the pressurized air technique is used to expand and axially slide the OSM over the ISM (prior to removing the ISM).
A specialized mandrel, for securely supporting a non-reinforced compliant ISM during mounting and demounting of an outer sleeve member of a double-sleeved roller, is included in a double-sleeved roller (DSR) which is disclosed in the Cormier, et al. patent application (U.S. patent application Ser. No. 10/______ filed with the U.S. Patent and Trademark Office on even date herewith) incorporated herein by reference. This DSR includes: a mandrel having a disconnectable end connected to three termination plates having specified outer shapes; a replaceable inner sleeve member (ISM) mounted on the mandrel; and, a replaceable outer sleeve member (OSM) with the OSM surrounding the ISM. The mandrel is adapted to support a non-reinforced ISM, the mandrel including the termination plates joined together so as to define two sets of channels for selectively conveying pressurized air to either OSM or ISM for radial expansion thereof. The outer shape of each termination plate includes a cylindrical portion adjoining a tapered portion. A preferred embodiment includes a single source pipe for providing the pressurized air to the two sets of channels. For removal and/or replacement of a sleeve member, a removable support member is moved away from the disconnectable end of the roller while the other end of the roller continues to be supported in cantilever fashion.
In relation to the double-sleeved roller disclosed in the co-filed Cormier et al. patent application cited above, it has been found by the inventors that removal from and/or replacement of an inner sleeve member from such a mandrel is problematical because of the way the inner sleeve member grips a tapered surface included in the mandrel, and also because the ISM is considerably stretched on the mandrel. Thus there remains a need to provide a device for easing the air-pressure-assisted sliding of inner sleeve members off, or on, such a mandrel. A removable fixture for providing such assistance, which fixture is attachable at the disconnectable end of the roller, is disclosed in the present invention.
A sleeve-replacement fixture is disclosed for employment in aiding removal and replacement of an inner sleeve member (ISM) of a double-sleeved roller (DSR). The DSR includes the ISM mounted on a mandrel and a replaceable outer sleeve member (OSM) surrounding the ISM. The mandrel, adapted to support a non-reinforced ISM, has a disconnectable end supported by a removable support member, at which disconnectable end are connected three termination plates having specified outer shapes: an inner termination plate, a middle termination plate, and an outer termination plate. Each of these outer shapes includes a cylindrical portion adjoining a conically tapered portion. The termination plates are joined together and mutually cooperate so as to form two internal chambers and two corresponding pluralities of radial channels for selectively conveying pressurized air from the respective internal chamber to the OSM or ISM for radial expansion thereof, with the internal chambers connectable to a single source of pressurized air. The two internal chambers of a fully-assembled DSR are mutually connectable via a pipe. This pipe is closed by a reversible blockage during operational use of the DSR and also during replacement or removal of the OSM. The blockage is removed and the pipe thereby opened in conjunction with use of the sleeve-replacement fixture of the invention.
The sleeve-replacement fixture (SRF) is a device temporarily attachable to the middle termination plate in lieu of the outer termination plate, with one of the pluralities of radial channels of the mandrel thereby left intact, i.e., those channels which lead to the underside of the inner sleeve member. The SRF is installed after partial disassembly of the DSR, i.e., after the removable support member, the OSM, the outer termination plate, and the blockage to the channels leading to the ISM are removed at the disconnectable end of the roller, with the other end of the roller supported in cantilever fashion.
In a preferred embodiment, the sleeve-replacement fixture (SRF) has a generally cylindrical symmetry, the SRF including two main members, a generally tubular member and a mating member (MM) in the form of a plate attached thereto, with each member having a specified outer shape. The tubular member has an end surface in contact with one side of the MM, with the other side of the MM for attachment to the middle termination plate of the mandrel. Attachment of the sleeve-replacement fixture causes the MM to cooperate with the outward surface of the middle termination plate so as to form an annular chamber and a plurality of radially-extending air passageways connecting this annular chamber and the perimeter of the MM, the annular chamber being connectable to a source of pressurized air, whereby a plurality of radially-directed air streams are created at the perimeter of the MM when pressurized air is introduced into the annular chamber. The MM also cooperates with the end surface of the tubular member so as to form an additional plurality of radially-extending air passageways to the perimeter of the MM. These two pluralities of radially-extending air passageways are mutually connected, in one-to-one fashion, by a plurality of bores passing through the MM. The bores are for transmitting pressurized air (i.e., from the annular chamber) to the plurality of radially-extending air passageways formed by the MM and the tubular member, thereby creating an additional plurality of radially-directed air streams. Installation of the SRF of the invention thus gives rise to a total of three sets of radial channels for conveying, from a single source pipe, pressurized air so as to produce three corresponding pluralities of radially-directed air streams to assist removal and replacement of an inner sleeve member.
A key feature of the invention relates to the specified outer shapes of the tubular member, the mating member (MM) of the SRF assembly, and the outer shape of the middle termination plate (MTP) to which the SRF attaches. Each of these three outer shapes includes an axially thin cylindrical portion and an adjoining conically tapered portion having a respective taper angle, and in the preferred embodiment, the taper angles of tubular member, the MM, and the MTP are all the same such that the surfaces of the three conically tapered portions are mutually defined by a conical envelope. Moreover, the tapered portion of the tubular member tapers into a cylindrical length of the tubular member, which cylindrical length merges into an adjacent continuously narrowing portion.
The invention, and its objects and advantages, will become more apparent in the detailed description of the preferred embodiment presented below.
In the detailed description of the preferred embodiments of the invention presented below, reference is made to the accompanying drawings, in some of which the relative relationships of the various components are illustrated, it being understood that orientation of the apparatus may be modified. For clarity of understanding of the drawings, some elements have been removed, and relative proportions depicted or indicated of the various elements of which disclosed members are composed may not be representative of the actual proportions, and some of the dimensions may be selectively exaggerated.
The subject invention discloses a novel sleeve-replacement fixture (SRF) for aiding replacement of an inner sleeve member (ISM) of a double-sleeved roller (DSR). The invention, used in conjunction with a partly disassembled DSR, is briefly described in the next paragraph and then described in detail with accompanying figures.
The DSR for use in conjunction with the invention is inclusive of a mandrel, with the ISM gripping the mandrel and an outer sleeve member (OSM) grippingly surrounding the ISM. The DSR has two ends including a disconnectable end supported by a removable support member. The disconnectable end includes a shaft member and a bearing mounted on the shaft member. The mandrel is inclusive of a sleeve-supporting member rotatably supported at the other end of the two ends of the DSR, with the sleeve-supporting member attached to an inner termination plate (ITP) at the disconnectable end. The ITP is also attached to a middle termination plate (MTP) with the MTP having an outer surface attached to an outer termination plate (OTP), the OTP of the DSR being operationally connected to the removable support member. The MTP cooperates with the ITP to form a plurality of radial channels therebetween which are connectable to a source of pressurized air, the radial channels terminating peripherally at a plurality of channel endings where pressurized air can be used to produce radial expansion of the ISM. In a fully assembled DSR, the plurality of radial channels is blocked from the source of pressurized air by a reversible blockage, which blockage is removed when the sleeve-replacement fixture of the invention is in use. The SRF is attached to a fixture-accepting configuration (FAC) derived from the DSR. The FAC is obtained by partially disassembling the DSR via the steps of (a) removing the removable support member from the disconnectable end, (b) removing the OSM, (c) removing the OTP, and (d) unblocking the blockage. The FAC includes (i) the sleeve-supporting member supported in cantilever fashion at the other end of the two ends, (ii) the ITP, (iii) the MTP which is equivalently called the end plate of the FAC, and (iv) the ISM. The sleeve-replacement fixture (SRF) includes a tubular member (TM) joined to a mating member (MM), with the MM for attachment to the end plate of the FAC. The TM and the MM cooperatively form a first set of radially-directed air passageways. With the sleeve-replacement fixture installed such that the MM is attached to the end plate of the FAC, the MM and the end plate cooperatively create a second set of radially-directed air passageways connectable to the source of pressurized air. The first set of radially-directed air passageways communicate, in one-to-one fashion, with the second set of radially-directed air passageways via a plurality of bores through the MM. With the source of pressurized air connected to the first and second sets of radially-directed air passageways, as well as to the plurality of radial channels formed by the ITP and the end plate (middle termination plate), three sets of radially-directed air jets are formed so that the inner sleeve member is slidably movable over the sleeve-replacement fixture and off the fixture-accepting configuration. Similarly, the three sets of radially-directed air jets are employed when mounting an ISM on a mandrel having a bare sleeve-supporting member, i.e., by slidably moving the ISM over the SRF to an operational position on the sleeve-supporting member. It is an important feature of the invention that the TM and the MM of the SRF are each provided with a taper which, in conjunction with tapers on each of the end plate and ITP of the FAC, promote the sliding of an inner sleeve member on or off the mandrel.
Turning now to
Sleeve-supporting member 120, labeled D, is rotatable about the roller axis and preferably has a predetermined outer diameter.
Inner termination plate (ITP) 115, labeled C, is operationally secured to the sleeve-supporting member 120.
Middle termination plate (MTP) 110, labeled B, is connected to the inner termination plate (ITP) 115. A preferably planar inward surface of the MTP has formed therein a plurality of radially-extending grooves extending from an annular recess to a perimeter of the MTP. This inward surface of the MTP and a preferably flat outward surface of the ITP cooperate to form an annular chamber and a plurality of radially-extending channels connecting the annular chamber and the perimeter of the MTP. The annular chamber is connectable to a source of pressurized air during removal or replacement of an inner sleeve member (ISM), whereby a plurality of radially-directed air streams or jets can be created at the perimeter of the MTP and at the inner surface of the ISM when pressurized air is introduced into the annular chamber. The plurality of radially-extending channels are ended by a corresponding plurality of terminations or openings, e.g., channel ending 111, from which the plurality of radially-directed air streams can be directed as described. Preferably the openings such as opening 111 are equally spaced circumferentially.
Outer termination plate (OTP) 105, labeled A, is operationally connected to the middle termination plate (MTP) 110, and is reversibly removable therefrom. A planar inward surface of the OTP has formed therein a plurality of radially-extending grooves extending from an annular recess to a perimeter of the OTP. This inward surface of the OTP and a flat outward surface of the MTP cooperate to form a second annular chamber and a second plurality of radially-extending channels connecting the second annular chamber and the perimeter of the OTP. The second annular chamber is connectable to the source of pressurized air, whereby a second plurality of radially-directed air streams or jets are created at the perimeter of the OTP and at the inner surface of the OSM when pressurized air is introduced into the second annular chamber. The second plurality of radially-extending channels are ended by a corresponding plurality of terminations or openings, e.g., channel end 106, from which the second plurality of radially-directed air streams can be directed as described. Preferably the openings such as opening 106 are equally spaced circumferentially.
With further reference to
As indicated in
Pressurized air can be introduced (see arrow b) via an entry port 137 leading into an interior volume 136 located inside axle member 135, and from thence into a pipe 138 and ultimately to the annular chambers described above.
In a condition with the mandrel of assembly 100 having mounted thereon both inner and outer sleeve members, pipe 138 leads directly through a hollow interior portion of sleeve-supporting member 120 to the second annular chamber formed by the contact between members A and B and from thence to the second plurality of openings exemplified by opening 106 so as to provide the above-described second plurality of radially-directed air streams for removal and/or replacement of an outer sleeve member. In this condition, shown in
The compliant sleeve member 202 is a non-reinforced member. Specifically, inner sleeve member (ISM 202) has no backing layer. ISM 202 is stretchably deformable and preferably grips surface 221 of sleeve-supporting member 220 with an interference of approximately 10 mm±5 mm. It is noteworthy that such a large interference ensures critical conformance of ISM 202 with the outer shape of the middle termination plate B′. (Interference is defined herein as an increase of inner diameter of the unstretched sleeve member after stretchably mounting the sleeve member so as to grip the underlying member, the underlying member having an outer diameter larger than the inner diameter of the unstretched sleeve member). ISM 202, which may include a thin flexible overcoat, preferably has a thickness in a range of approximately between 0.2 mm and 14 mm, and more preferably, has a thickness of 0.500 mm±0.005 mm.
The portion 204b of plate C′ having a cylindrical outer shape has an axial length which is not critical, typically less than about 2 mm. Axial thickness of ITP 115 as measured between flat outer face 212 and the flat inner face 209 is not critical, typically about 7±3 mm. Similarly, the portion 203b of plate B′ having a cylindrical outer shape has an axial length preferably in a range of approximately between 2 mm-6 mm. Axial thickness of MTP 210 as measured between flat outer face 211 and flat inner face 222 is preferably in a range of approximately between 12 mm-16 mm.
To replace inner sleeve member 202, the following preparatory sequential steps are employed: the disconnectable support member (not shown in
OTP 340 is formed having an annular recess such that with OTP 340 attached to MTP 330 as shown, the OTP 340 and the MTP 330 cooperate so as to form a second annular chamber 345. In addition, the OTP 340 and the MTP 330 cooperate so as to form a plurality of radially-extending channels connecting chamber 345 and the perimeter of OTP 340, the passageways terminating at channel endings such as endings 343 (corresponding to endings 106 in
A pipe 311 is provided for transporting pressurized air into chamber 345 for purpose of removing or replacing the partially-mounted outer sleeve member 360 (indicated by the double ended arrow, x . . . x′). Pipe 311 is connectable to a source for the pressurized air, with pipe 311 housed in a hollow portion of member 310. Pipe 311 is connected to an assembly for supplying the pressurized air to chamber 345 via a nozzle 356. A bore 337 connects chambers 345 and 355. A replaceable preferably deformable plug member 336, made for example of rubber, is preferably seated as illustrated on the inward face of the outer termination plate 340 and urged by the OTP 340 against the outward end of bore 337 so as to seal bore 337 and thus prevent pressurized air from passing from chamber 345 into chamber 355. The plug member 336 preferably has a flat surface in contact with OTP 340 and a rounded surface, such as a spherical section, pressed against the outlet of bore 337 as indicated. Annular grooves 332 and 334, for respectively housing O-ring seals 333 and 335, are formed in the outer and inner faces of the middle termination plate 330.
Roller portion 300 is provided with a shaft member 317 which is rotatable inside a bearing 315 having a housing with a cylindrical surface 318, the bearing being secured on shaft member 317 by a nut 316. For demounting or mounting of the outer sleeve member 360 (in directions x, x′) the illustrated end of roller portion 300 is disconnected (see
Outer termination plate (OTP) 340 is provided with an axially centered round hole defined by circular wall 319, which round hole has a diameter larger than the outer diameter of the cylindrical surface 318. Thus with outer sleeve member 360 completely demounted (slid off the roller in the direction, x) and the bolts 341 removed, the (OTP) 340 is readily removable by translating it in the direction, x, and thereby passing it over the housing of the roller bearing 315. Removal of (OTP) 340 for purpose of replacing the inner sleeve member 350 also permits removal of the plug 336. A guide pin 342 is used to accurately guide positioning of (OTP) 340 and to assist in reinstallation of the bolts 341.
A ring-shaped insulator member 305 made from a ceramic material (and a similar ring-shaped insulator member at the other end of the roller, not shown) provide electrical insulation of the mandrel from the shaft member 319. Thus the mandrel is electrically biasable to any suitable voltage by a power supply, such as indicated in
Another plurality of radial grooves (not visible in
A plurality of bores (not shown in
The MM 520 further includes a central hole 524, which central hole projects into a tubular extension 540 extending axially in a direction away from the inward surface, the tubular extension extending from the central hole.
Sleeve-replacement fixture 500 is assembled via two bolts (not illustrated in
The grooves having groove ends 525 form, in cooperation with flat surface 511, a first set of radially-directed air passageways including at least 8 radially-directed air passageways. With the sleeve-replacement fixture installed on the preferred FAC of
For installation of SRF 500 on FAC portion 400, threaded bolt ends 516, which project through TM 510, pass through holes 523 and are screwed into receptacles 415 of
The circular plate-like portion 535 has a specified outer shape, preferably a tapered shape tapering (towards member 510 as illustrated) from a maximum diameter equal to the diameter of the outer perimeter of surface 521 (see also
The tubular member (TM) 510 is generally cylindrically symmetrical about a central axis (for example axis 551,
The specified outer shape of the preferred tubular member 510 includes an axially thin cylindrical portion 556 terminating at the flat end surface 511, with portion 556 adjoining a conically tapered portion 555 having a maximum outer diameter and a minimum outer diameter, with the maximum diameter equal to the outer diameter of the axially thin cylindrical portion. The conically tapered portion 555 defined by a taper angle preferably in a range of approximately between 5°-30°.
The taper angle of the conically tapered portion 421 of end plate (middle termination plate) 330 of
The conically tapered portion 555 adjoins a cylindrical length 560, the cylindrical length having an outer diameter which is substantially constant and equal to the minimum outer diameter of the conically tapered portion.
The cylindrical length 560 further adjoins a gradually narrowing portion 565 of the tubular member 510, the gradually narrowing portion having a greatest outer diameter equal to the diameter of the cylindrical length, with the gradually narrowing portion monotonically decreasing in diameter from this greatest outer diameter between perimeters 513 and 514. Preferably, there is an axially thin end section 570 of the tubular member 510 located between the perimeter 514 and a terminal face 529 of TM 510, which end section has a rounded shape to aid the mounting of an inner sleeve member on the fixture 550.
The gradually narrowing portion 565 can have any suitable shape. Preferably, the shape of portion 565 has a profile defined by arcs which are portions of circles having centers at points X and Y. Thus an arc centered at point X is tangent to the surface of cylindrical portion 560 at point Y, with the arc continuing to perimeter 514. In an exemplary embodiment, perimeter 513 can have a diameter of 162.57 mm with an arc radius of 575 mm±5 mm.
Preferably tubular member 510 and mating member 520 are made of an aluminum alloy and are preferably externally coated by an anodized hardcoat. Furthermore, at least a portion of SRF 550 includes an outer coating of any suitable low surface energy (LSE) material. Preferably, the low surface energy material is a fluoropolymer having a thickness in a range of approximately between 0.025-0.10 mm. The fluoropolymer is preferably coated on to anodized hardcoated tubular member 510. More preferably, the coating material is a PTFE (polytetrafluorethylene) material obtainable from General Magnaplate Corp. of Linden, N.J., under the tradename “Lectrofluor 615”. This PTFE material is coated via a vacuum deposition process to a preferred thickness of about 0.05 mm.
An enlargement,
The annular depression 530 connects to the relatively wide radially-directed groove 531 which enters a bore 610 passing through circular plate-like portion 535. Also entering bore 610 is a relatively narrow radial groove 580 terminating at the groove end 525. Groove 580, in cooperation with surface 511 of tubular member 510 (
It is preferred, as illustrated in
Taper angles α′, β′, γ, and θ respectively define the conically tapered portions 419, 421, 575, and 555. As indicated in
More generally, it is preferred that each of the specified number of degrees of angles β′, γ, and θ is equal to an indicated angle in common, φ. As shown in
In structure 750, it is preferred that the length L1, which is equal to the combined axial thicknesses of tapered portion 555 and cylindrical portion 556, be about 6 mm±1 mm. Preferably, the thickness of cylindrical portion 556, l1, is in a range of approximately between 0.5 mm-2.0 mm, and more preferably is about 0.93 mm. Preferably, the length L2, which is equal to the combined axial thicknesses of tapered portion 575 and cylindrical portion 756, is about 14.0 mm, and preferably the thickness of cylindrical portion 756, l2, is in a range of approximately between 0.5 mm-2.0 mm, and more preferably is about 0.93 mm. Preferably, the length L3, which is equal to the combined axial thicknesses of tapered portion 421 and cylindrical portion 420, is about 14.0 mm, and preferably the thickness of cylindrical portion 420, l3, is about 3.8 mm. The length L4, which is equal to the combined axial thicknesses of tapered portion 419 and cylindrical portion 418, is not critical, and is typically about 7 mm. Preferably, the thickness of cylindrical portion 418, l4, is about 1.0 mm or less.
Notwithstanding the above-disclosed preferred values of taper angles and axial thicknesses in structure 750, it is to be understood that any suitable individual values of taper angles and axial thicknesses may be used.
In the preferred embodiment 800 of
As illustrated in
The terminations of the pluralities of radially-directed grooves 525, 585 giving rise to the radially-directed air passageways for producing jets 805, 810 are not rotationally staggered, relative to one another, around central axis 551. Each set of terminations is separated pairwise by a specified angle subtended at central axis 551, which specified angle is preferably 15° as illustrated. However, the channel endings of the plurality of radial channels located peripherally between members 330 and 320 are preferably rotationally staggered, relative to the terminations of the pluralities of radially-directed grooves 525 and 585, by a rotational angle equal to one-half of the specified angle subtended at central axis 551, i.e., by 7.5° in
A method is disclosed for replacing an inner sleeve member (ISM) included in a fixture-accepting configuration (FAC), the FAC derived from a double-sleeved roller by partial disassembly thereof, the method utilizing a sleeve-replacement fixture (SRF) for reversible attachment to the FAC, the FAC including (i) a sleeve-supporting member (SSM) supported in cantilever fashion at one end of two ends of the SSM, (ii) an inner termination plate (ITP) attached to the sleeve-supporting member at the other end of the SSM, (iii) an end plate (EP) attached to the ITP, and (iv) the ISM, the ITP having a cylindrical portion and an adjoining conically tapered portion, the ISM grippingly surrounding the SSM as well as the cylindrical portion of the ITP, the ISM extending over the adjoining conically tapered portion of the ITP with the ISM further grippingly surrounding the cylindrical portion of the EP as well as a part of an adjoining conically tapered portion of the EP, the EP cooperatively forming with the ITP a plurality of radial channels connectable to a source of pressurized air deliverable from the source to the ISM for radial expansion thereof, the SRF including a tubular member having a low-surface-energy coating and a mating member (MM) attached thereto, the tubular member and the MM cooperatively forming a first set of radially-directed air passageways for connection to the source of pressurized air, the MM having two faces connected by a plurality of bores leading into the first set of radially-directed air passageways, each of the tubular member and the MM having an axially thin cylindrical portion adjacent a conically tapered portion with the conically tapered portion tapering away from the axially thin cylindrical portion, wherein in a condition with the SRF attached to the FAC the conically tapered portions of the TM and the MM and the EP are mutually defined by a conical envelope, wherein in the condition with the SRF attached to the FAC the axially thin cylindrical portions of the MM and the tubular member are closer to the other end of the SSM than are the conically tapered portions, such that the conically tapered portions taper in a direction away from the other end of the SSM, the tubular member further including a cylindrical length smoothly adjoining the conically tapered portion where the tapered portion of the tubular member has a minimum outer diameter, the cylindrical length adjoining a gradually narrowing portion of the tubular member, the gradually narrowing portion having a greatest outer diameter equal to the diameter of the cylindrical length, the method for replacing the ISM on the FAC including the steps of (a) connecting the MM of the SRF to the EP such that the MM and the EP cooperatively create a second set of radially-directed air passageways connectable to the source of pressurized air, the bores joining in one-to-one fashion the second set of radially-directed air passageways to the first set of radially-directed air passageways (b) opening the source of pressurized air, thereby supplying pressurized air to the plurality of radial channels, to the first set of radially-directed air passageways, and via the bores to the second set of radially-directed air passageways (c) slidably moving the ISM off the FAC (d) with the source of pressurized air open, slidably moving a replacement ISM to an operational location on the FAC (e) closing the source of pressurized air, and (f) disconnecting the SRF from the EP.
A method is disclosed for replacing an inner sleeve member (ISM) grippingly mounted on a mandrel included in a double-sleeved roller (DSR), the DSR having two ends, the two ends including a disconnectable end operationally supported by a removable support member, the DSR including an outer sleeve member (OSM) surrounding the ISM, the mandrel inclusive of a rigid sleeve-supporting member having joined thereto at the disconnectable end three termination plates having specified outer shapes, each of which outer shapes including a cylindrical portion adjacent a conically tapered portion, the termination plates including an inner termination plate (ITP), a middle termination plate (MTP), and an outer termination plate (OTP), wherein the ISM extends so as to cover the cylindrical portion of the ITP and a part of the adjacent conically tapered portion of the MTP, the OSM extending over the ITP and beyond the MTP so as to substantially cover only the cylindrical portion of the OTP, the MTP cooperatively forming with the ITP a first plurality of radial channels connectable to a source of pressurized air selectably deliverable from the source to said ISM for radial expansion thereof, the first plurality of radial channels being blocked from the source by a reversible blockage, the OTP cooperatively forming with the MTP a second plurality of radial channels, the second plurality of radial channels not blocked by a blockage and thus directly connectable to the source, the pressurized air deliverable from the source to the OSM for radial expansion thereof, the method utilizing a disconnectably attachable sleeve-replacement fixture comprising a tubular member and a mating member (MM) joined thereto, the tubular member and the MM cooperatively forming a first set of radially-directed air passageways for connection to the source of pressurized air, the MM having two faces connected by a plurality of bores leading into the first set of radially-directed air passageways, each of the tubular member and the MM having an axially thin cylindrical portion adjacent a conically tapered portion, with the conically tapered portion tapering away from the axially thin cylindrical portion, wherein in a condition with the SRF attached to the FAC, the axially thin cylindrical portions of the MM and the tubular member are closer to the other end of the SSM than are the conically tapered portions, such that the conically tapered portions taper in a direction away from the other end of the SSM, the tubular member further including a cylindrical length smoothly adjoining the conically tapered portion where the tapered portion of the tubular member has a minimum outer diameter, the cylindrical length adjoining a gradually narrowing portion of the tubular member, the gradually narrowing portion having a greatest outer diameter equal to the diameter of the cylindrical length, the method for replacing the ISM on the DSR including the steps of (a) moving the removable support member away from the disconnectable end with the mandrel supported in cantilever fashion at the other end of the two ends (b) opening the source of pressurized air to the second plurality of radial channels (c) slidably moving the OSM off the mandrel (d) closing the source of pressurized air (e) removing the outer termination plate from the MTP (f) unblocking the reversible blockage (g) connecting the MM of the sleeve-replacement fixture to the MTP such that the MM and the MTP cooperatively create a second set of radially-directed air passageways connectable to the source of pressurized air, the bores joining in one-to-one fashion the second set of radially-directed air passageways to the first set of radially-directed air passageways (h) opening the source of pressurized air, thereby supplying pressurized air to the first plurality of radial channels, to the first set of radially-directed air passageways, and via the bores to the second set of radially-directed air passageways (i) slidably moving the ISM off the mandrel (j) with the source of pressurized air open, slidably moving a replacement ISM to an operational location on the mandrel (k) closing the source of pressurized air (l) disconnecting the sleeve-replacement fixture from the MTP (m) blocking, with a reversible blockage, the source of pressurized air from reaching the first plurality of radial channels (n) replacing the outer termination plate thereby reforming the first plurality of radial channels (O) reopening the source of pressurized air (p) slidably moving an OSM over the replacement ISM to an operational location on the mandrel; and (q) closing the source of pressurized air.
The invention has been described in detail with particular reference to certain preferred embodiments thereof, but it will be understood that variations and modifications can be effected within the spirit and scope of the invention.
Reference is made to the following commonly assigned application, the disclosure of which is incorporated herein by reference: U.S. patent application Ser. No. ______, filed on even filing date herewith, by Steven O. Cormier, et al., entitled, “DOUBLE-SLEEVED ELECTROSTATOGRAPHIC ROLLER”;
Number | Date | Country | |
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60523619 | Nov 2003 | US |