Abstract: An elastomeric seal ring is located between each bearing pin and each cone of an earth-boring bit. An excluder ring or band is imbedded within the inner diameter of the seal ring. A portion of the inner diameter of the seal ring as well as the excluder ring are in dynamic sealing contact with the bearing pin. The excluder ring may be harder and more wear resistant than the seal ring. The excluder ring may have lubricating properties. An outer excluder ring may be located on the outer diameter of the seal ring for engaging the cone to resist rotation.

Abstract: An earth bit includes a cutting cone rotatably mounted to a lug, and a seal assembly positioned to provide a seal between the cutting cone and lug. The seal assembly includes first and second rigid rings, and a first elastomeric sealing ring which carries the first rigid ring. The second rigid ring rotates in response to the rotation of the first elastomeric sealing ring, so that the second rigid ring is less likely to lock.

Abstract: A mechanical device is used to estimate a service life of an air filter exposed to a certain chemical at various concentrations, flow rates, and relative humidity conditions. The device includes two members, one of which has at least one window, connected so that their surfaces are movable relative to one another. One member has numerical values for chemical concentrations and service life estimates printed on it. The member having windows has at least one mark printed on it by which it can be oriented relative to the chemical concentration scale on the other member. When the two members are aligned relative to a chemical concentration of interest, the corresponding service life estimate is displayed in an appropriate window.

Abstract: An earth bit seal includes a magnetic ring that determines how strongly the earth bit seal engages a lug and/or cone of an earth bit. The earth bit seal also includes a flexible ring positioned away from any dynamic sealing surfaces that engage the lug or cone. The flexible ring is positioned away from the dynamic sealing surfaces so that, if it becomes impregnated with debris, it will not act as an abrasive ring that undesirably removes material from them, or from the lug and cone.

Abstract: An earth bit includes an earth bit body which carries a lug. The lug is repeatably attachable to and detachable from the earth bit body. A retaining ring retains the lug to the earth bit body and restricts the movement of the lug in response to a force applied to it. The retaining ring has a height less than its diameter.

Abstract: An earth bit includes an earth bit body having a bore with a bearing passageway in fluid communication therewith. A screen extends through the bore and is repeatably moveable between rolled and unrolled conditions. The screen is in the rolled condition when extending through the bore. The screen screens a material flowing between the bore and bearing passageway.

Abstract: An earth bit includes a cutting cone mounted to a lug to form a bearing cavity. A valve is in fluid communication with the bearing cavity and a bit chamber, wherein the valve includes a diaphragm with an aperture. The aperture is repeatably moveable between open and closed conditions in response to a pressure difference between the material in the bearing cavity and bit chamber.

Abstract: An earth bit includes a cutting cone rotatably mounted to a lug with a hub unit. A sealing member is positioned to provide a seal between the cutting cone and lug. The sealing member includes an O-ring core enclosed by a sleeve having a seam extending annularly around it. The seam restricts the rotation of the sleeve around the O-ring core.

Abstract: An earth bit includes a cutting cone rotatably mounted to a lug with a journal. A sealing member is sealingly engaged with the cutting cone and a wear ring carried by the lug. The wear ring is dynamically engaged with the first sealing member and statically engaged with the lug.

Abstract: An elastomeric seal ring is located between each bearing pin and each cone of an earth-boring bit. An excluder ring or band is imbedded within the inner diameter of the seal ring. A portion of the inner diameter of the seal ring as well as the excluder ring are in dynamic sealing contact with the bearing pin. The excluder ring may be harder and more wear resistant than the seal ring. The excluder ring may have lubricating properties. An outer excluder ring may be located on the outer diameter of the seal ring for engaging the cone to resist rotation.

Abstract: A drill bit has a plurality of air tubes extending into the bowl for separating entrained debris and liquids from air flow used to clean and cool bearings in the cutters of the bit. The air tube is assembled from a tube and a cap. The tube has open ends and a plurality of openings through the sidewall of the tube for allowing air to flow through the openings while preventing large debris from entering the tube. The lower end of the tube is inserted into an inner portion of a fluid passage, and the cap is secured to the upper end of the tube. The cap is removable for providing access to the interior of the tube when necessary to dislodge debris from within the tube.

Abstract: A bit is provided having at least one leg extending downwardly and inwardly from the bit body. A cutter cone is rotatably mounted on a shaft extending inwardly from the lower portion of each leg. The annular space defined by the base of the shaft and the inner surface at the base of the cone forms a seal gland. An elastomeric o-ring sealingly engages an inner surface of the cone and a first rigid ring which rotates with the o-ring and cone. The o-ring energizes the first rigid ring for sealingly engaging a second rigid ring mounted to the leg of the bit near the base of the shaft. The second rigid ring is secured to and seals against a surface at the base of the shaft and is held stationary relative to the surface. A lubricant passage for lubricating the seal is pressurized by the drilling fluid pressure in the center of the bit body.

Abstract: A bit is provided having at least one leg extending downwardly and inwardly from the bit body. A cutter cone is rotatably mounted on a shaft extending inwardly from the lower portion of each leg. The annular space defined by the base of the shaft and the inner surface at the base of the cone forms a seal gland. An elastomeric o-ring sealingly engages an inner surface of the cone and a first rigid ring which rotates with the o-ring and cone. The o-ring energizes the first rigid ring for sealingly engaging a second rigid ring mounted to the leg of the bit near the base of the shaft. The second rigid ring is secured to and seals against a surface at the base of the shaft and is held stationary relative to the surface. A lubricant passage for lubricating the seal is pressurized by the drilling fluid pressure in the center of the bit body.

Abstract: A method is described for logically isolating a cache memory bank from the other cache memory banks, as well as from the associated disk drive system and the computer system, while allowing effective use of the remaining cache banks. Linked lists of pointers to free space in a given cache bank are located entirely within the bank; therefore, failure of, or removal of, a cache bank does not prevent the computer and disk drive system from utilizing the free space in the remaining banks. The implementation of the method is such that initialization of all cache memory banks may also be efficiently performed.

Abstract: A method is described for managing data records stored in non-volatile memory in a disk drive system with cache memory. A variable-length directory containing descriptors of disk records is used to locate a selected record non-volatile memory. A table, ordered sequentially by record number, is used to quickly locate a record in non-volatile memory without having to perform a time-consuming search. In order to efficiently utilize space in non-volatile memory, a list is kept of free space for storing record descriptors. After an initial nominal allocation, additional free space is allocated only when required, thus further increasing the efficiency of use of non-volatile memory.