1. A xerographic printing method, comprising:
uniformly charging a photoreceptor of a tri-level xerographic imaging unit to a predetermined voltage;
creating tri-level electrostatic images including CAD image areas and DAD image areas having different voltage levels, VCAD and VDAD, respectively, on the photoreceptor, where a background discharge level VW is located between VCAD and VDAD in which no image may be developed;
developing one of the CAD image areas and DAD image areas with a first toner of a first color and developing the other of the CAD image areas and DAD image areas with a second toner of a second color that is a hypochromatic light form of the first toner to form a composite separation image of a desired image in which the first and second colors are developed without any overlap; and
transferring the first composite separation image onto a substrate.
2. The xerographic printing method of claim 1, wherein the first and second colors are selected from one of the following sets of colorants: (a) cyan and light cyan; (b) yellow and light yellow; (c) magenta and light magenta; and (d) black and gray.
3. The xerographic printing method of claim 1, further comprising using at least two tri-level xerographic imaging units, the second xerographic imaging unit including a third toner of a color different from the first toner and a corresponding fourth toner that is a hypochromatic light form of the third toner.
4. The xerographic printing method of claim 3, further comprising using three tri-level xerographic imaging units, the first xerographic imaging unit comprising cyan and light cyan toners, the second xerographic imaging unit comprising yellow and light yellow toners, and the third xerographic unit comprising magenta and light magenta toners.
5. The xerographic printing method of claim 1, further comprising using four tri-level xerographic imaging units, the first xerographic imaging unit comprising cyan and light cyan toners, the second xerographic imaging unit comprising yellow and light yellow toners, the third xerographic unit comprising magenta and light magenta toners, and the fourth xerographic unit comprising black and gray toners.
6. The xerographic printing method of claim 1, further comprising image processing the image so that low to mid-tone portions of the tone reproduction curve (TRC) are produced solely by the second hypochromatic color toner and higher portions of the TRC are produced by non-overlapping combinations of the first color toner andor the second hypochromatic color toner.
7. The xerographic printing method of claim 6, further comprising applying a near maximum area coverage of colorant for a given location on the TRC by maximizing the use of the lighter colorant.
8. The xerographic printing method of claim 1, further comprising:
adjusting a blending curve of the first color toner and second hypochromatic color toner to avoid gamut loss or ink-limit violation.
9. The xerographic printing method of claim 1, further comprising forming of white border regions between the first and second color toners.
10. A xerographic machine, comprising:
a photoreceptor; and
a tri-level xerographic imaging unit including
a charging device for charging the photoreceptor to a predetermined voltage;
an imaging system for obtaining tri-level electrostatic images including CAD image areas on the photoreceptor having a first voltage level VCAD, and DAD image areas on the photoreceptor having a second voltage level VDAD lower than the first voltage level, and a background discharge level VW between the first and second voltage levels at which neither the CAD image areas nor the DAD image areas may be developed; and
first and second developer units for developing the CAD image areas and the DAD imaging areas with a first colorant toner of a first color from one of the developer units and a second colorant toner that is a hypochromatic light form of the first colorant toner from the other of the developer units, wherein one of the toners is developed in the CAD image areas and the other toner is developed in the DAD image areas to form a first composite color separation of a desired image in which the first and second toners are developed without any overlap.
11. The xerographic machine according to claim 10, wherein the first and second colors are selected from one of the following sets of colorants: (a) cyan and light cyan; (b) yellow and light yellow; (c) magenta and light magenta; and (d) black and gray.
12. The xerographic machine according to claim 10, further comprising using at least two tri-level xerographic imaging units, the second xerographic imaging unit including a third toner of a color different from the first toner and a corresponding fourth toner that is a hypochromatic light form of the third toner.
13. The xerographic machine according to claim 10, further comprising using three tri-level xerographic imaging units, the first xerographic imaging unit comprising cyan and light cyan toners, the second xerographic imaging unit comprising yellow and light yellow toners, and the third xerographic unit comprising magenta and light magenta toners.
14. The xerographic machine according to claim 10, further comprising using four tri-level xerographic imaging units, the first xerographic imaging unit comprising cyan and light cyan toners, the second xerographic imaging unit comprising yellow and light yellow toners, the third xerographic unit comprising magenta and light magenta toners, and the fourth xerographic unit comprising black and gray toners.
15. The xerographic machine according to claim 10, wherein the xerographic imaging unit processes the image so that low to mid-tone portions of the tone reproduction curve (TRC) are produced solely by the second hypochromatic color toner and higher portions of the TRC are produced by non-overlapping combinations of the first color toner andor the second hypochromatic color toner.
16. The xerographic machine according to claim 10, wherein the xerographic imaging unit applies a near maximum area coverage of colorant for a given location on the TRC by maximizing the use of the lighter colorant.
17. The xerographic machine according to claim 10, further comprising:
an adjustment mechanism that adjusts a blending curve of the first color toner and second hypochromatic color toner to avoid gamut loss or ink-limit violation.
18. The xerographic machine according to claim 10, wherein the xerographic imaging unit forms white border regions between the first and second color toners.
19. A xerographic printing method, comprising:
uniformly charging a photoreceptor of a tri-level xerographic imaging unit to a predetermined voltage;
creating tri-level electrostatic images including CAD image areas and DAD image areas having different voltage levels, VCAD and VDAD, respectively, on the photoreceptor, where a background discharge level VW is located between VCAD and VDAD in which a white border region is produced;
developing one of the CAD image areas and DAD image areas with a first toner of a first color and developing the other of the CAD image areas and DAD image areas with a second toner of a second color that is a hypochromatic light form of the first toner to form a composite separation image of a desired image in which the first and second colors are developed without any overlap; and
transferring the first composite separation image onto a substrate.
20. The xerographic method according to claim 19, further comprising image processing the image so that low to mid-tone portions of the tone reproduction curve (TRC) are produced solely by the second hypochromatic color toner and higher portions of the TRC are produced by non-overlapping combinations of the first color toner andor the second hypochromatic color toner.
21. The xerographic method according to claim 20, further comprising applying a near maximum area coverage of colorant for a given location on the TRC by maximizing the use of the lighter colorant.
22. The xerographic method according to claim 19, further comprising:
adjusting a blending curve of the first color toner and second hypochromatic color toner to avoid gamut loss or ink-limit violation.
23. The xerographic method according to claim 19, wherein the first and second colors are selected from one of the following sets of colorants: (a) cyan and light cyan; (b) yellow and light yellow; (c) magenta and light magenta; and (d) black and gray.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A mud motor radial bearing comprising:
a rotatable cylindrical steel support having a generally cylindrical outer surface, at least portions of the outer surface having bonded thereto a bearing material, the bearing material comprising a plurality of tungsten carbide portions surrounded by a hard metal alloy matrix, the hard metal alloy matrix comprising at least one carbide selected from carbides of chrome, carbides of boron, and mixtures thereof, the remainder of the hard metal alloy matrix comprising a binder metal selected from iron, cobalt, nickel, and mixtures thereof; and
a portion of a stationary cylindrical bearing housing having a generally cylindrical inner surface against which an outer surface of the bearing material interfaces as the rotatable cylindrical steel support rotates.
2. The mud motor radial bearing according to claim 1 wherein the at least one carbide is present at a weight percentage of at least 30 weight percent, based on total weight of the at least one carbide and binder.
3. The mud motor radial bearing according to claim 1 wherein the generally cylindrical outer surface of the rotatable cylindrical steel support comprises a reduced diameter portion in which the bearing material is positioned so that the bearing material outer surface is flush with the balance of the generally cylindrical outer surface of the rotatable cylindrical steel support.
4. The mud motor radial bearing according to claim 1 wherein the rotatable cylindrical steel support is a portion of a rotatable member of a mud motor bearing assembly.
5. The mud motor radial bearing according to claim 4 wherein the rotatable member of the mud motor bearing assembly is a flow diverter, and the portion is a box connection of the flow diverter.
6. The mud motor radial bearing according to claim 1 wherein the plurality of tungsten carbide portions are bonded to the generally cylindrical outer surface of the rotatable cylindrical steel support using a heat attachment method.
7. The mud motor radial bearing according to claim 6 wherein the heat attachment method comprises tack welding.
8. The mud motor radial bearing according to claim 1 wherein the plurality of tungsten carbide portions are solid cylinder-shaped having an outer diameter (OD) ranging from about 0.100 inch up to about 0.500 inch (2.54 mm to 12.7 mm).
9. The mud motor radial bearing according to claim 1 wherein the plurality of tungsten carbide portions are solid cylinder-shaped having height ranging from about 0.03 inch up to about 0.25 inch (0.762 mm to 6.35 mm).
10. A combination flow diverter and integral radial mud motor bearing comprising:
a generally cylindrical flow diverter body defining first and second threaded box ends, a concentric longitudinal bore, a generally cylindrical outer surface, and a longitudinal axis;
the longitudinal bore fluidly connecting first and second threaded box end bores, the first threaded box end bore configured to threadedly connect to a pin of a transmission of a mud motor rotor, the second threaded box end bore configured to threadedly connect to a pin of a mandrel;
one or more flow diverter ports extending from the longitudinal bore to the outer surface of the body, fluidly connecting the longitudinal bore with an annulus between the outer surface and a mud motor housing and configured to route fluid from the annulus into the concentric longitudinal bore; and
the generally cylindrical outer surface of the body in a region of the second threaded box end having bonded thereto a bearing material, the bearing material comprising a plurality of tungsten carbide portions surrounded by a hard metal alloy matrix, the hard metal alloy matrix comprising at least one carbide selected from carbides of chrome, carbides of boron, and mixtures thereof, the remainder of the hard metal alloy matrix comprising a binder metal selected from iron, cobalt, nickel, and mixtures thereof.
11. The combination flow diverter and integral radial mud motor bearing of claim 10 wherein the second threaded box end bore is tapered, being smaller in diameter toward the longitudinal bore, the diameter increasing toward an exit of the second threaded box end bore.
12. The combination flow diverter and integral radial mud motor bearing of claim 10 wherein the at least one carbide is present at a weight percentage of at least 30 weight percent, based on total weight of the at least one carbide and binder.
13. The combination flow diverter and integral radial mud motor bearing of claim 10 wherein the plurality of tungsten carbide portions are bonded to the generally cylindrical outer surface of the second threaded box end using an adhesive system.
14. The combination flow diverter and integral radial mud motor bearing of claim 10 wherein the plurality of tungsten carbide portions are solid cylindrical-shaped having an outer diameter (OD) ranging from about 0.100 inch up to about 0.500 inch (2.54 mm to 12.7 mm), and having height ranging from about 0.03 inch up to about 0.25 inch (0.762 mm to 6.35 mm).
15. The combination flow diverter and integral radial mud motor bearing of claim 10 wherein the flow diverter ports are each positioned at an angle ranging from about 20 to about 70 degrees, the angle measured from a line perpendicular to the longitudinal axis to a line through a longitudinal axis of the port.
16. A mud motor bearing assembly comprising:
a generally cylindrical housing;
the combination flow diverter and integral radial mud motor bearing of claim 10 positioned within the housing;
a generally cylindrical mandrel having a pin end fluidly connected to the second threaded box end of the flow diverter, and a box end configured to fluidly attach to a drill bit;
a lower radial bearing comprising a heat shrink-fitted sleeve heat-shrunk onto a first portion of an outer surface of the mandrel; and
one or more thrust bearings positioned in an annular space generally defined by a first portion of an inner surface of the housing, a second portion of the outer surface of the mandrel, the second box end of the flow diverter, and the lower radial bearing.
17. The mud motor bearing assembly of claim 16 wherein the tungsten carbide portions may be the same or different in size, shape, and position from region to region, and the tungsten carbide portions may have the same or different composition from region to region.
18. The mud motor bearing assembly of claim 16 further comprising a mandrel catch integral with the heat shrink-fitted sleeve.
19. The mud motor bearing assembly of claim 16 wherein the flow diverter has three ports arranged at 120 degree angles between them.
20. A mud motor bearing assembly comprising:
a generally cylindrical housing;
the combination flow diverter and integral radial mud motor bearing of claim 10 positioned within the housing;
a generally cylindrical mandrel having a pin end fluidly connected to the second threaded box end of the flow diverter, and a box end configured to fluidly attach to a drill bit;
a lower radial bearing comprising a sleeve threadedly connected to a first portion of an outer surface of the mandrel;
a mandrel catch comprising a safety nut threadedly connected to the sleeve, the safety nut having a lower portion capable of interfering with an inner shoulder of the generally cylindrical housing; and
one or more thrust bearings positioned in an annular space generally defined by a first portion of an inner surface of the housing, a second portion of the outer surface of the mandrel, the second box end of the flow diverter, and the lower radial bearing.