The Timken Company

Spinadyne, Inc.

William E Harbottle

Tadao Tsuneyoshi

Mark A Joki

Richard A Knepper

Dennis L Otto

Tai Friesem

Manoj Krishna

Steven Brown

Keith M Gordon

Neal C McBain

Thomas A Ballas

Jay M Landry

Russell W Keller

Rahil Hasan

James Eddie Jones

Joseph P Berecek

Larry L Keller

Lawrence L Musselman

The present invention provides a pedicle screw system, which may include a bone fixation element having an elongate body. The elongate body may include a threaded segment having one or more spiral-oriented grooves, a neck segment adjacent to the threaded segment, and a head segment which is able to receive and/or couple to an orthopedic instrument or implant. The pedicle screw system may further include an anchoring element movably positionable about the bone fixation element. The anchoring element may include one or more elongate teeth which may be slidably positionable into a desired tissue region.

Pedicle screw system

A spindle rotates within a housing on at least two antifriction bearings which have raceways that are inclined to the axis of the bearing and are otherwise configured to transfer thrust loading as well as radial loading. The bearings are mounted in opposition. One of the bearings has a race which fits into an actuator sleeve with an interference fit, and the actuator sleeve, in turn, is fitted into the housing, it having end regions that are located beyond the ends of the bearing. Here the sleeve is fitted to the housing with an interference fit and is further sealed to the housing. The actuator sleeve also has an intervening region between its two end regions, and here the actuator sleeve is located around the race. On its opposite face the actuator sleeve forms a chamber with the housing. When the chamber is pressurized, the intervening region of the sleeve flexes inwardly and contracts the race, thus altering the setting of the two bearings. Yet the end regions of the sleeve remain against the housing and the axis of rotation remains rigid. A control system monitors conditions, such as temperature, within the housing, and varies the pressure in the chamber behind the actuator sleeve, so that the setting in the bearings best accommodates the conditions under which the spindle operates.

Bearing with adjustable setting

The preload in a double row production bearing assembly is ascertained by comparing the deflection produced in that bearing assembly by oppositely directed thrust forces with the deflection produced in a master bearing assembly by equivalent thrust forces likewise applied in opposite directions. The master bearing assembly is similar in configuration and substantially equal in stiffness to the production bearing assembly, but exists in a state of end play. Each thrust force is transferred through the rolling elements of one row and should be sufficient in magnitude to unseat the rolling elements of the other row. The preload in the production bearing assembly equals the end play in the master bearing assembly plus the deflection in the production assembly less the deflection in the master assembly. The endplay in the master bearing assembly is ascertained by extrapolating the deflection to zero thrust force.

Method of measuring preload in a multirow bearing assembly

An angular contact ball bearing has races formed from a case-carburized or carbonitrided steel, preferably a stainless steel, that withstands high forces and high temperatures. The bearing has relatively low osculation ratios to reduce the generation of heat, yet can withstand applied radial loads and the centrifugal forces generated in high speed operation.

High speed angular contact ball bearing

A rotary air bearing (A) as shown in the Figure has a journal ( ) provided with a pair of outwardly presented tapered surfaces located opposite the tapered surfaces on the journal, and a low friction liner ( ) bonded to the tapered surfaces on the hub and having tapered surfaces which are separated from the tapered surfaces of the journal by small air gaps (g).

Rotary air bearing and process for manufacturing the same

A high speed antifriction bearing receives minute quantities of high performance grease or oil at selected intervals from an electrically controlled injector having a nozzle that is directed at the rolling elements of the bearing. By minimizing the lubricant in the bearing, the lubricant does not accumulate in quantities that render it susceptible to working. The high performance lubricant produces a boundary layer film between contacting critical surfaces within the bearing. That film is so thin that it has little capacity to churn or work and produce heat. The injector may be the type used for electronic injection of diesel fuel into the cylinders of diesel engines.

Lubrication system for high speed antifriction bearings

A compact locking nut has a body provided with a threaded bore along which the nut engages a thread so that upon rotation it will advance over a thread to a position suitable for securing and positioning a machine component such as a bearing. The nut has a machined back face along which it bears against the secured machine component and a front face at its other end. The body contains two grooves--one external in that it opens outwardly from the exterior surface and the other internal in that it opens into the bore--and these grooves divide the body into a clamping section, a locking section, and an intervening web which is thin enough to flex with relative ease. The external groove lies closest to the back face, whereas the internal groove lies closest to the front face. On its exterior the body has lands which extend out to the front face. Typically, the body derives from a forging having the lands and a bore. The threads, the two grooves, and the back face are all machined while the body is gripped along its lands in a chuck with the front face in the chuck. In other words, essentially all of the machining is performed in a single setup. Machine screws pass through the locking section and web and thread into the clamping section, and when turned down drive the locking section over the clamping section to jam the threads of the nut on the thread engaged by the nut. The nut may as be provided in an inside-out variation.

Locking nut

A hub rotates around a spindle on bearings which have angular raceways so that the bearings are capable of carrying both axial and radial loads and may be adjusted into a condition of preload with an axially directed force applied to one of the races, usually the outboard race on the spindle. That force which represents the preload in the bearings, is transmitted through a force sensor which produces a signal that reflects the magnitude of the force. By monitoring the force sensor, one can adjust the bearings to a desired preload.

Bearing adjustment using compressive force sensor

A machine measures an object of generally circular cross-section by superimposing on the subject a cylindrical coordinate system having five axes, namely a vertical measuring axis Z, three radial axes R0, R120, R240 emanating at a common point along the measuring axis Z, and a rotational axis .theta. having its center at the measuring axis Z. The machine includes an elevating unit which supports the object with its axis generally parallel to the measuring axis Z and is further capable of moving the object parallel to the measuring axis Z as well as rotationally about the measuring axis Z along the rotational axis .theta.. A measuring device monitors the linear position of the object along the axis Z while another measuring device measures the angular position of the object along the rotational axis .theta.. In addition, the machine includes three measuring heads, there being one along each radial axes R0, R120, and R240, and each measuring head includes a base, a slide which is mounted on the base for movement parallel to the radial axis of its head, and a probe carried by the slide. The probe has a displaceable probe tip which bears against a surface on the object. Each measuring head has a measuring device for monitoring the position of its slide relative to the slide base and as well as another monitoring device which may be used to monitor the position of the probe tip relative to the slide along the radial axis R or the position of the probe tip parallel to the measuring axis Z. The machine scans the object by effecting relative movement between the object and probe tips parallel to one of the axes while at least one of the probe tips remains against the object, and by taking measurements at equally spaced intervals along another of the axes. Thus, it is possible to make an axial scan, a radial scan, a rotary scan along a circumferential surface or a rotary scan along an end surface.

Machine for measuring generally circular objects in cylindrical

A shaft is confined within a housing by two indirectly mounted tapered roller bearings, and these bearings are adjusted by applying opposed axial forces to their cups, the spacing between which is dependent on the thickness of a deformable spacer located within the housing. A force of sufficient magnitude is applied to plastically deform the spacer that is between the two cups, and as the force is applied the spacing between the raceways of the two cups is monitored. The force is released when the size of the spacer will cause the cup raceways to be spaced apart a distance which provides the bearings with the correct adjustment. This distance is determined by measuring a master cup and adjusting the dimension so derived for the desired amount of end play or preload and for spring back of the spacer, hub and cups when the load is released. The process may be used where the cones are press-fitted over the shaft and have their front faces abutting. In that case, further adjustments from the raceway spacing of the master may be made to accommodate changes in the positioning of the cone raceways which result from variations in the cone bore diameters and in the locations of the cone front faces. The measurement of the cone bore diameters and front face locations are made in a fixture and compared with measurements derived from master cones which are also measured in the fixture, all for the purpose of determining deviations from the master cones.

Adjusting process for bearings

A single row tapered roller bearing capable of taking radial loading as well as thrust loading in both axial directions has a cone provided with an integral thrust rib at the small diameter end of its raceway, a cup surrounding the cone, tapered rollers between the raceways of the cup and cone, a separate rib ring at the large diameter end of the cup raceway, and a cage for maintaining correct spacing between the rollers in the circumferential direction. The cage at one end has an outwardly directed lip which is too large to fit through the rib ring and at its other end has outwardly directed tabs which are too large to fit through the cup without deflecting. In effect, the cup and rib ring are captured between the lip and tabs on the cage, and since the rib ring and cup cannot separate, the rollers and cone remain in place, providing a bearing which is unitized sufficiently for normal handling.

Unitized single row tapered roller bearing

A shaft is confined within a housing by two indirectly mounted tapered roller bearings, and these bearings are adjusted by applying opposed axial forces to their cups, the spacing between which is dependent on the thickness of a deformable spacer located within the housing. A force of sufficient magnitude is applied to plastically deform the spacer that is between the two cups, and as the force is applied the spacing between the raceways of the two cups is monitored. The force is released when the size of the spacer will cause the cup raceways to be spaced apart a distance which provides the bearings with the correct adjustment. This distance is determined by measuring a master cup and adjusting the dimension so derived for the desired amount of end play or preload and for spring back of the spacer, hub and cups when the load is released. The process may be used where the cones are press-fitted over the shaft and have their front faces abutting. In that case, further adjustments from the raceway spacing of the master may be made to accommodate changes in the positioning of the cone raceways which result from variations in the cone bore diameters and in the locations of the cone front faces. The measurement of the cone bore diameters and front face locations are made in a fixture and compared with measurements derived from master cones which are also measured in the fixture, all for the purpose of determining deviations from the master cones. Where an integral double cup is used (no spacer) the measuring procedure is useful for selective assembly of cups and cones into bearing assemblies, with the three components being selected such that they result in a bearing having the correct adjustment.

A bearing assembly has a shaft extended through a double cup with opposed tapered raceways machined directly into the cup and shaft. A row of tapered rollers is positioned between each pair of raceways, and the rollers of each row are mounted in opposition and substantially on apex. Expulsion of the rollers is prevented by annular rib rings which are press-fitted over the shaft and embrace the shaft at the large diameter ends of the tapered raceways thereon. The shaft has grooves which underlie the rib rings and enhance the holding power of the rings.

Growing community of inventors

Fort Lauderdale, FL, United States of America

William E Harbottle