| Class / Patent application number | Description | Number of patent applications / Date published |
|---|
| 175371000 | With bearing or seal details | 48 |
| 20080257610 | Elastomer Material for High Temperature Roller Cone Bits - An earth boring bit has a bit body with at least one bearing pin. A cone is rotatably mounted on the bearing pin. A seal assembly is located between the cone and the bearing pin, the seal assembly having at least one flexible seal member. A flexible pressure compensating diaphragm is mounted in the body. The diaphragm has one side adapted to be exposed to borehole fluids and another side in contact with lubricant contained in bearing spaces between the cone and the bearing pin. The flexible seal member and the diaphragm are formed of a fluorinated elastomer. The elastomer is either a perfluoroelastomer (FFKM) or a fluoroelastomer (FKM). | 10-23-2008 |
| 20090014217 | Roller Cone Bit Bearing, and Bearing Materials - A journal bearing element for use in forming a roller cone bit coupled to a bearing shaft to prevent circumferential sliding. Also included are material compositions of the journal bearing element. A journal bearing element is fixed in place relative to a head section and comprised of dense high purity powdered metal alloys with uniform micro-structure. A preferred material is comprised of a metal made of a carbon content of about 2.3% by weight, chromium of about 14% by weight, vanadium of about 9% by weight, and molybdenum at about 1% by weight. | 01-15-2009 |
| 20090038858 | USE OF NANOSIZED PARTICULATES AND FIBERS IN ELASTOMER SEALS FOR IMPROVED PERFORMANCE METRICS FOR ROLLER CONE BITS - A bit for drilling subterranean formations that includes a bit body including a bearing surface; a cutting structure mounted on the bit body, and including a bearing surface, and an annular seal for retaining a grease between the bearing surfaces, the annular seal comprising a flexible and resilient seal body formed from an elastomer composition, wherein the elastomer composition comprises an elastomer material, a curing agent, and 10% or less by volume of a nanomaterial additive selected from one of nanotubes and clustered nanodiamonds is disclosed. | 02-12-2009 |
| 20090114452 | ROCK BIT WITH A THERMAL INSULATING SEAL RING POSITIONED IN THE SEAL GLAND - A rock bit includes a shaft and a cone mounted for rotation about the shaft at a journal bearing. A seal gland for the rock bit is defined at least by the shaft and the cone. A compressible seal ring is positioned within the seal gland. A thermal insulating ring is installed within the seal gland and positioned between the compressible seal ring itself and the journal bearing to insulate the compressible seal ring from heat radiating from the journal bearing. | 05-07-2009 |
| 20090194339 | EARTH BORING BIT WITH WEAR RESISTANT BEARING AND SEAL - A roller cone bit is provided that includes a wear resistant coating applied to a bearing shaft, which is attached to a roller cone. The wear resistant coating can be a tungsten/tungsten carbide composite applied by chemical vapor deposition. | 08-06-2009 |
| 20090205873 | DOWNHOLE TOOL BEARING SYSTEM CONTAINING DIAMOND ENHANCED MATERIALS - Downhole tool bearings are provided with diamond enhanced materials. The diamond enhanced materials comprise diamond grains in a matrix of tungsten or silicon carbide. A brazed diamond grit or diamond particles coated with a reactive braze may be utilized for bearing applications. Bearing rings formed at least in part with diamond enhanced material are installed on at least one of the bearing pin journal, the nose and the cone cavity. The bearing rings may be continuous rings or partial rings and attached to the journal pin or cone cavity. These may include thrust bearings, rollers, roller race, balls and ball races made of diamond enhanced material. These bearing surfaces also are formed at least in part with diamond enhanced material and attached to portions of the journal or cone bearing surfaces. | 08-20-2009 |
| 20090321146 | Earth Boring Bit with DLC Coated Bearing and Seal - A roller cone bit is provided that includes a wear resistant diamond-like carbon coating applied to a bearing shaft, where it is in sliding contact with the bearing seal. The wear resistant diamond-like carbon coating reduces wear and corrosion of the head bearing shaft sealing surface and provides extended life to the bearing seal. | 12-31-2009 |
| 20100018778 | SEAL COMPRISING ELASTOMERIC COMPOSITION WITH NANOPARTICLES - Seals and sealing members are formed from a composition generally comprising a first elastomeric material and a second elastomeric material, wherein the second elastomeric material comprises a dispersion of nanosized particles disposed within a polymer matrix of the second elastomeric material. Preferred first and second elastomeric materials are fluoroelastomers, and preferred nanosized particles are fluoropolymers. The nanosized particles are sized less than about 100 nm. The composition comprises about 0.2 to 65 percent by weight of first elastomeric material, about 20 to 95 percent by weight of second elastomeric material, and about 10 to 90 percent by weight particles based on the total weight of the particles and the second elastomeric material. The composition can be used to form annular O-ring seals placed within rotary cone bits used for drilling subterranean formations, and can be used to form a selected portion of the seal or the entire seal. | 01-28-2010 |
| 20100038144 | ROLLER BEARING SEAL COMPANION RING HAVING TEXTURED SURFACE FOR HOLDING LUBRICANT AND SMALL PARTICLES - A roller cone bit is provided that includes a companion ring positioned exterior to a seal, wherein the companion ring includes a textured surface where the inner diameter of the companion ring contacts the bearing pin. | 02-18-2010 |
| 20100071960 | System, Method and Apparatus for Composite Seal Gland Insert in Roller Cone Rock Bit - A composite seal gland insert for a roller cone rock bit is a polymer composite sleeve containing one or more constituents that function to significantly lower the wear of the elastomeric seal ring. A fluid lubricant film also may be used between the elastomer seal and the gland. The outer surface of the insert is profiled to provide a sealing surface against which the elastomer seal runs. The insert is installed over the bearing pin and has a surface that engages the last machined surface of the leg. A static seal, which may comprise an additional elastomeric seal, may be used beneath the gland insert to provide a pressure seal between the insert and the pin. An adhesive also may be used as the pressure seal and also to retain the gland insert in the desired position. In addition, a mechanical anti-rotation device may be used to prevent rotation of the gland insert. | 03-25-2010 |
| 20100089657 | SPACER RING FOR ELASTOMERIC SEAL - A roller cone bit is provided that includes a companion ring positioned adjacent to the seal, wherein the companion ring is formed of a porous material that is compatible with the fluid lubricating the interface between the roller cone and the bearing pin. | 04-15-2010 |
| 20100147595 | BEARING SEAL WITH IMPROVED CONTACT WIDTH - A high aspect ratio seal is provided for large roller cone drill bit having a diameter of greater than about 12¼ inches wherein the contact width is narrowed, relative to the width of the seal, to provide a desired contact width. | 06-17-2010 |
| 20100163313 | Engineered Bearing Surface For Rock Drilling Bit - A drill bit bearing having a treated surface and method for preparing the same is provided. The method includes the steps of polishing at least one contacting surface of the bearing with an abrasive paste to a finish of less than about 10 μin Ra. The surface of the polishing instrument has a coating that includes a mixture of an epoxy cement and a polymer. | 07-01-2010 |
| 20100193251 | ROCK BIT HAVING A SEAL GLAND WITH A CONICAL SEALING SURFACE - A sealing system is provided for a drill bit including a bit head and a rotating bit cone. The sealing system includes a seal gland and a seal retained within the seal gland. The seal gland is defined by a radial cone surface and is further defined by a head sealing surface and an opposed cone sealing surface. At least one of the head sealing surface and opposed cone sealing surface is not cylindrical (i.e., the surface is conical and not parallel to an axis of rotation for the cone). Additionally, the radial cone surface may be conical (i.e., the surface does not extend perpendicular to the axis of rotation of the cone). The seal is radially compressed between the head sealing surface and the opposed cone sealing surface. The use of one or more conical surfaces in the gland is provided to bias the compressed seal into a preferred dynamic sealing zone. | 08-05-2010 |
| 20100230172 | SEAL ASSEMBLY FOR A ROTARY EARTH BIT - An earth bit includes a cutting cone carried by a lug, and an interstice seal assembly which forms a dynamic seal with a radial interstice lug surface of the lug. The interstice seal assembly includes a rigid sealing ring having lengthened and shortened arm portions. The lengthened arm portion extends outwardly from the shortened arm portion, and engages the radial interstice lug surface. | 09-16-2010 |
| 20100320002 | ROCK BIT WITH A THERMAL INSULATING SEAL RING POSITIONED IN THE SEAL GLAND - A rock bit includes a shaft and a cone mounted for rotation about the shaft at a journal bearing. A seal gland for the rock bit is defined at least by the shaft and the cone. A compressible seal ring is positioned within the seal gland. A thermal insulating ring is installed within the seal gland and positioned between the compressible seal ring itself and the journal bearing to insulate the compressible seal ring from heat radiating from the journal bearing. | 12-23-2010 |
| 20110024198 | BEARING SYSTEMS CONTAINING DIAMOND ENHANCED MATERIALS AND DOWNHOLE APPLICATIONS FOR SAME - Downhole tool bearings are provided with diamond enhanced materials. The diamond enhanced materials comprise diamond grains in a matrix of tungsten or silicon carbide or a silicon bonded diamond material. A brazed diamond grit or diamond particles coated with a reactive braze may be utilized for bearing applications. Bearing rings for use in downhole tools may be formed at least in part with the diamond enhanced material. In one embodiment, the bearing rings may be used in a positive displacement motor. In additional embodiments, the bearing rings may be used in a submersible pump. | 02-03-2011 |
| 20110048810 | SYNERGIC SURFACE MODIFICATION FOR BEARING SEAL - The present invention relates to a method and apparatus for forming a dynamic seal between two surfaces. More specifically, the invention relates to creating a textured surface with a thin, hard coating on a metallic annular sealing ring such as the sealing ring used in an earth boring drill bit. | 03-03-2011 |
| 20110061940 | CONFORMAL BEARING FOR ROCK DRILL BIT - A rock drilling bit having PDC radial bearings has journal and cone bearing surfaces with increased contact area to increase load support. The radius of curvature of the bearing pin journal and cone bearing surfaces are matched or conformed on the bearing pressure side. The conformal journal surfaces may be formed on the main journal bearing, the pilot pin radial bearing, or both surfaces. In addition, diamond inlays may be located on the bearing surfaces of the cone, the bearing pin, or both components. | 03-17-2011 |
| 20110079444 | External, Divorced PDC Bearing Assemblies for Hybrid Drill Bits - A hybrid-type earth boring drill bit is described having fixed cutting blades and rolling cones with cutting elements, wherein the rolling cones are associated with a spindle assembly that may be optionally divorced from the head pin assembly, and which includes bearing members that further include a plurality of polycrystalline diamond elements. | 04-07-2011 |
| 20110168450 | DRILL BIT BEARING CONTACT PRESSURE REDUCTION - A method of reducing contact pressure between bearing surfaces of a drill bit can include constructing a structure which supports one bearing surface in contact with the other bearing surface, and reducing contact pressure between the bearing surfaces by relieving strain energy in the structure. A drill bit can include one bearing surface which contacts another bearing surface. There is a transition between contact and lack of contact between the bearing surfaces. A structure supporting one of the bearing surfaces has a reduced stiffness, whereby a contact pressure between the bearing surfaces is reduced at the transition. | 07-14-2011 |
| 20110174547 | BEARING ASSEMBLIES, AND BEARING APPARATUSES AND MOTOR ASSEMBLIES USING SAME - Various embodiments of the present invention relate to bearing assemblies configured to accommodate non-uniform loading and misalignment with an adjacent bearing assembly. In one embodiment of the present invention, a bearing assembly for use in a subterranean drilling system is disclosed. The bearing assembly includes a support ring and a retention ring attached to the support ring, with the retention ring including a plurality of through holes. The bearing assembly includes a plurality of bearing elements each of which includes a superhard bearing surface. Each of the bearing elements is positioned in and extends from a corresponding through hole of the plurality of through holes. At least a number of the bearing elements are configured to restrict displacement through the corresponding through hole and away from the support ring. Further embodiments of the present invention are directed to a thrust-bearing apparatus, a radial bearing apparatus, and a downhole motor that incorporates disclosed thrust-bearing and radial bearing assemblies. | 07-21-2011 |
| 20110220422 | EARTH - BORING CUTTER MOUNT AND ASSEMBLY - A rotary cutter mount for an earth-boring cutter is provided which includes a ball bearing journal [ | 09-15-2011 |
| 20110220423 | TRI-CONE BIT FOR HIGH RPM DRILLING APPLICATIONS - This invention relates to a tri-cone bit for high RPM drilling applications, which comprises three head sections and three cones. Cutting elements are arranged on each cone. Upper parts of the three head sections are joined together to form a bit body, on which nozzle sockets are provided, and nozzles are installed in bores of the nozzle sockets. A bearing between the cones and the head sections is a composite roller-journal bearing which is formed by rollers and arc-shaped slides arranged in an alternating way, and a seal means for the bearing is of metal face type. The composite roller-journal bearing of the invention can withstand high RPM and high load, and also has a higher resistance to impact, thereby ensuring longer working life of the bearing under high RPM and medium-high WOB. The six-point gage protection structure enhances stability of the bit and reduces cutting element breakage caused by bit vibration. The above tri-cone bit is suitable for high RPM and medium-high WOB drilling applications and features high drilling efficiency and long service life. | 09-15-2011 |
| 20110297448 | ROCK BIT HAVING A MECHANICAL SEAL WITH SUPERIOR THERMAL PERFORMANCE - A drill tool includes a bit body, at least one bearing shaft extending from the bit body and a cone mounted for rotation on the bearing shaft. A mechanical seal is disposed between the bearing shaft and the cone in a seal gland. The mechanical seal includes a rigid seal ring having a dynamic sealing surface with the cone and another non-sealing surface exposed to an aperture in the seal gland. The mechanical seal further includes at least one cooling channel formed in the another non-sealing surface of the rigid seal ring, the cooling channel having an open end in fluid communication with the aperture in the seal gland. | 12-08-2011 |
| 20110315453 | SEAL ASSEMBLY FOR DRILL BIT - A drill bit includes a floating journal bushing, a seal, a cutter having a seal gland for the seal and a cutter bearing surface proximate to the journal bearing, wherein the cutter bearing surface has a first inner diameter, and a journal, wherein the cutter is rotatably coupled about the journal, wherein the journal bearing is rotatably coupled about the journal, wherein the journal has a seal boss having a first diameter, and a journal bearing surface having a second diameter, and wherein the first diameter is less than the first inner diameter. | 12-29-2011 |
| 20120024608 | PATTERNED TEXTURING OF THE SEAL SURFACE FOR A ROLLER CONE ROCK BIT - Surface texturing is employed to modify the topography of one or more surfaces (radial or cylindrical) of the sealing system for a roller cone rock bit. The surface texturing produces a regular or repeated patterned dimpled surface which retains additional lubricant helpful in reducing friction in the boundary and mixed lubrication regimes. | 02-02-2012 |
| 20120111639 | DRILL BIT WITH EXTENDED LIFE SEAL - Systems and methods are provided for swellable material activation and monitoring in a subterranean well. A sensor system for use in a subterranean well includes a swellable material, and at least one sensor which is displaced to a wellbore surface in response to swelling of the swellable material. Another sensor system includes a sensor which detects swelling of a swellable material. A swellable well tool system includes a base pipe, a swellable material on an exterior of the base pipe, and eccentric weighting for inducing rotation of the swellable material about a longitudinal axis of the base pipe. | 05-10-2012 |
| 20120160572 | Vibration-Resistant Seal for Downhole Tool - A seal ring assembly for a well drilling tool that takes the place of conventional O-rings that are prone to costly downhole failures. In a first embodiment the seal ring assembly is configured with a convex adapter seal ring at one end, a concave adapter seal ring at the other end, and a number of V-shaped component seal rings packed in between the convex and concave adapter seal rings and positioned in the space between a drill collar mandrel and a pressure cylinder of the well drilling tool. In a second embodiment the seal ring assembly is configured with a number of X-shaped component seal rings, each of which is fitted with two O-rings. The seal ring assemblies are able to flex when operating in a bent drill hole so as to maintain seal integrity and prevent fluids from passing through to the electronics region of the well drilling tool. | 06-28-2012 |
| 20120228035 | DRILLING APPARATUS - A drilling apparatus including a housing, a drill bit having a head end, a connection end, and a bearing mandrel between the head end and the connection end, a bearing pack associated with the bearing mandrel and the housing for transmitting forces between the drill bit and the housing, the bearing pack including at least one bearing interposed between the bearing mandrel and the housing, and a drive mechanism connected with the connection end of the drill bit, for driving the drill bit. | 09-13-2012 |
| 20120285748 | Bearing Assembly - A bearing assembly for use in an apparatus having a housing and a shaft which is rotatably connected with the housing. A shaft extension extends from the interior of the housing at a first housing end. The shaft extension defines a first bearing shaft surface. The bearing assembly includes a first thrust bearing for transferring a first axial load between the shaft and the housing. The first thrust bearing is located axially between the first housing end and the first bearing shaft surface. | 11-15-2012 |
| 20120312602 | HIGHLY WEAR RESISTANT COMPOSITE ROTARY SEALS WITH WEAR LAYER AT INNER DIAMETER AND/OR OUTER DIAMETER EMBEDDED INSIDE OR BETWEEN RUBBER LAYERS - A composite journal seal for use in a roller cone drill bit may include a substantially ring shaped elastomeric body having at least two axial, radial, or canted sealing surfaces, at least one of the at least two axial, radial, or canted sealing surface being a dynamic sealing surface, and at least one reinforcement layer embedded at least 0.005 inches from the at least one dynamic sealing surface. | 12-13-2012 |
| 20130020135 | ROCK BIT HAVING A LABYRINTH SEAL/BEARING PROTECTION STRUCTURE - A drill tool includes a cone mounted for rotation on a bearing shaft that extends from a bit head. The cone has a first planar base surface opposed to a second planar base surface of the bit head. A first annular groove is formed in the first planar base surface, and a second annular groove is formed in the second planar base surface. The first and second annular grooves are at least partially aligned with each other. The combination of the first and second annular grooves form a first annular gland. A protector ring is inserted into the first annular gland, and functions to divide a fluid path between the bearing shaft of the drill tool and an external environment into a plurality of parallel fluid paths that pass around the protector ring. Each parallel fluid path includes a convolution defined by a plurality of fluid direction changing corners. | 01-24-2013 |
| 20130133955 | DRILL BIT WITH SEAL HAVING SPHERES IN A MATRIX SEAL MATERIAL - A drill bit can include a seal which seals against a drill bit surface, the seal including a matrix seal material and a plurality of hollow spheres in the matrix seal material. Another drill bit can include a seal with a matrix seal material, spheres being more dense in a portion of the matrix seal material as compared to in the matrix seal material outside of the portion, and the portion of the matrix seal material being in dynamic sealing contact with a drill bit surface during operation. A drill bit can include a seal between a cone and a journal, the seal comprising a matrix seal material and a plurality of spheres in the matrix seal material, the matrix seal material comprising nitrile. | 05-30-2013 |
| 20140196956 | HIGH SHEAR ROLLER CONE DRILL BITS - A drill bit may include a bit body, comprising: at its upper end, a connection adapted to connect to a drill string; at its lower end, a plurality of journals extending downwardly and radially outward from a longitudinal axis of the bit; a plurality of roller cones rotatable mounted on the plurality of journals; and at least three rows of cutting elements disposed on each of the plurality of roller cones, wherein an outermost row has an extension height to diameter ratio greater than a mid row, and the mid has an extension height to diameter ratio greater than an innermost row. | 07-17-2014 |
| 20140216824 | TOOL HOLDER, AND CHISEL SUPPORT AND DRILLING BIT FOR A DRILL HEAD - A drill head including a tool holder, chisel supports mounted thereon and drill bits. According to this invention, the chisel supports can be separated from the tool holder. | 08-07-2014 |
| 20150144406 | Composite Metallic Elastomeric Sealing Components for Roller Cone Drill Bits - An earth boring bit has a bit body with a depending bearing pin, a eons rotatably mounted on the hearing pin, a seal gland between the cone and the bearing pin, and a seal assembly located in the seal gland. The seal assembly includes an annular metallic spring encircling the bearing pin. The spring has a geometric center line that extends in a circle around the bearing pin. The spring is elastically deform able in radial directions relative to the center line. An elastomeric layer is located on an exterior side of the spring and is biased by the spring against a surface of the seal gland. | 05-28-2015 |
| 20150322724 | ROTARY DRILL BIT - An air-cooled earth-boring drill bit including a plurality of lugs. Each lug includes a pin flange. A first roller race is distal to the pin flange. A thrust flange is distal to the first roller race. At least one pin flange vent slot is arranged in a surface of the pin flange opposite the first roller race. The at least one pin flange vent slot opens in a direction of a load side of a bearing. At least one thrust flange vent slot is arranged in a surface of the thrust flange facing the first rollers. The at least one thrust flange vent slot opens in the direction of the load side of the bearing. A plurality of flow passages are arranged within the lug to supply fluid to the at least one pin flange vent slot and the at least one thrust flange vent slot. | 11-12-2015 |
| 20150330152 | Enhanced Backup Ring Edge Features for Metal Face Seal in Roller Cone Drill Bits - A backup ring for a face seal in a roller cone bit is configured to resist wear from drilling fluids present adjacent exposed faces of the backup ring. Portions are removed from an exposed end face in a variety of shapes while the hardness of the material is increased. The removal of material offsets an increase in force that would be transmitted through the backup ring on face seal assembly due to flexing. A spring can optionally be included in the removed material location. Another way is to increase the edge density of all or part of the exposed edges while leaving the interior portions unaffected by using electron beam radiation to increase the crosslink density or by other techniques that allow a unitary structure with a more durable edge region. | 11-19-2015 |
| 20150345226 | SYMMETRICAL HAR SEAL - A downhole seal system for roller cone drill bits includes a seal gland having a width larger than it depth. In one implementation, the seal gland includes a protrusion along its base on which a seal element seats. The seal element is a single, annular seal element with a recess formed therein so as to define two lobes. The seal element seats in the gland so that the recess engages the protrusion. The lobes function as separate seal elements, although they are a single unitary seal element disposed in a single gland. | 12-03-2015 |
| 20160040482 | ROLLER CUTTER WITH IMPROVED SEALING - A roller cutter intended to be used at a drill head for rotary boring of the front of earth and rock formations, the roller cutter having a centre line and being provided with a hub having rows of crushing members. At least one crushing member has its longitudinal axis at an angle relative to a normal to the centre line. The hub is rotatable in relation to a shaft having shaft spigots. The roller cutter is provided with at least one seal retainer arranged at an axial end of the hub in order to hold a sealing means in position. The hub includes at least one circumferential recess positioned axially inward relative to a radially inward projecting flange in the hub. | 02-11-2016 |
| 20160194918 | SACRIFICIAL SPACER FOR WELL TOOL INNER SEAL | 07-07-2016 |
| 20160201397 | ELASTOMER-THERMALLY CONDUCTIVE CARBON FIBER COMPOSITIONS FOR ROLLER-CONE DRILL BIT SEALS | 07-14-2016 |
| 20160251903 | SEAL ASSEMBLIES FOR EARTH-BORING TOOLS, EARTH-BORING TOOLS SO EQUIPPED, AND RELATED METHODS | 09-01-2016 |
| 175372000 | Antifriction type | 4 |
| 20090107731 | DRILLBIT SEAL - A drillbit seal ( | 04-30-2009 |
| 20090229886 | Non-Grease Type Bearing Lubricant - The present disclosure includes a lubricant for use in a roller cone rock bit, where the lubricant comprises a non-grease formulation. The lubricant can comprise synthetic lubricating fluids and combinations thereof as well as combinations of synthetic fluid or fluids with mineral oil or oils. The lubricant can contain one or more additional ingredients and have a minimum viscosity of 100 centistokes at 212° F. The additional ingredients include fluid soluble or dispersed extreme pressure and antiwear additives, and solid lubricants. | 09-17-2009 |
| 20110168451 | Boron Aluminum Magnesium Coating for Earth-Boring Bit - A rotatable cone earth boring bit has a bearing system with at least on the surfaces being AlMgB14 alloy material. The alloy material also contains an alloying agent, which may be titanium boride (TiB2); titanium carbide (TiC) plus iron, nickel and carbon; silicon nitride (Si3N4) powder; whiskered silicon nitride (Si3N4); boron carbide (B4C); titanium boride (TiB2); or tungsten boride (W2B4). The surface containing the AlMgB14 alloy material may be a journal surface or thrust face on the bearing pin. The surface containing the AlMgB14 alloy material may also be a seal surface, either on a metal face seal or a gland on the bearing pin engaged by an elastomeric ring. The AlMgB14 alloy material may a coating or it may be a free-standing structural member within the bearing system. | 07-14-2011 |
| 20130092448 | Bearing Assembly for Rotary Drills - A bearing assembly is for a rotary drill, the drill including a base with a shaft and a bit. The bearing assembly includes a bearing having a central axis and including an inner member disposeable on the shaft and an outer member disposed about the inner member. The outer member is angularly displaceable about the axis with respect to the inner member and having an outer circumferential surface and a recess extending generally radially inwardly from the outer surface. At least one and preferably a plurality of retainer members are each disposed at least partially within the bearing outer member recess and is configured to engage with the bit so as to rotatably couple the bit with the shaft. Preferably, each retainer member includes a generally spherical ball rollable through a passage and into the bearing recess during installation into the recess. | 04-18-2013 |
