Patent Publication Number: US-2022212323-A1

Title: Systems and methods for preloading a bearing and aligning a lock nut

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application is a continuation of U.S. Ser. No. 16/679,956 filed on Nov. 11, 2019, entitled “Systems and Methods for Preloading a Bearing and Aligning a Lock Nut”, published as U.S. Publication No. 2020/0078913-A1 on Mar. 12, 2020 (Attorney Docket No. 0545.105B), which is a continuation of U.S. Ser. No. 15/885,988 filed on Feb. 1, 2018, entitled “Systems and Methods for Preloading a Bearing and Aligning a Lock Nut”, published as U.S. Publication No. 2018/0161967-A1 on Jun. 14, 2018 (Attorney Docket No. 0545.105A), which is a divisional of U.S. Ser. No. 15/071,570 filed on Mar. 16, 2016, entitled “Systems and Methods for Preloading a Bearing and Aligning a Lock Nut”, published as U.S. Publication No. 2017/0266792 A1 on Sep. 21, 2017 (Attorney Docket No. 0545.105). The entire disclosure of these applications is incorporated herein by reference. 
     This application is related to U.S. Ser. No. 12/492,826 filed on Jun. 26, 2009, entitled “Systems and Methods for Preloading a Bearing and Aligning a Lock Nut”, now U.S. Pat. No. 8,316,530 issued on Nov. 27, 2012 (Attorney Docket No. 0545.057), the entire disclosure of which is incorporated herein by reference. 
     This application also relates to U.S. Ser. No. 13/683,571, filed on Nov. 21, 2012, entitled “Methods for Preloading a Bearing and Aligning a Lock Nut”, now U.S. Pat. No. 8,650,752 issued on Feb. 18, 2014 (Attorney Docket No. 0545.057A), the entire disclosure of which is incorporated herein by reference. 
     This application also relates to U.S. Ser. No. 14/160,045, filed on Jan. 21, 2015, entitled “Systems and Methods for Preloading a Bearing and Aligning a Lock Nut”, now U.S. Pat. No. 8,904,646 issued on Dec. 9, 2014, (Attorney Docket No. 0545.057B), the entire disclosure of which is incorporated herein by reference. 
     This application also relates to U.S. application Ser. No. 11/341,948, filed Jan. 27, 2006, and titled “Method and Apparatus for Preloading a Bearing”, issued as U.S. Pat. No. 7,559,135 on Jul. 14, 2009 (Attorney Docket No. 0545.049), the entire disclosure of which is incorporated herein by reference. 
     This application also relates to U.S. application Ser. No. 11/354,513, filed Feb. 15, 2006, and titled “Method, Apparatus, and Nut for Preloading a Bearing”, issued as U.S. Pat. No. 7,389,579 on Jun. 24, 2008 (Attorney Docket No. 0545.051), the entire disclosure of which is incorporated herein by reference. 
     This application also relates to U.S. Ser. No. 12/033,548, filed on Feb. 19, 2008, entitled “Axle Nut”, now U.S. Pat. No. 8,961,090 issued on Feb. 24, 2015, (Attorney Docket No. 0545.051A), the entire disclosure of which is incorporated herein by reference. 
     This application also relates to U.S. Ser. No. 12/492,926, filed Jun. 26, 2009, entitled “Methods for Preloading a Bearing”, now U.S. Pat. No. 8,359,733 issued on Jan. 29, 2013, (Attorney Docket No. 0545.051B), the entire disclosure of which is incorporated herein by reference. 
     This application also relates to U.S. Ser. No. 14/305,830, filed Jun. 16, 2014, entitled “Lock Nut System”, now U.S. Pat. No. 9,200,673 issued on Dec. 1, 2015, (Attorney Docket No. 0545.051C), the entire disclosure of which is incorporated herein by reference. 
     This application also relates to U.S. Ser. No. 14/305,673, filed Jun. 16, 2014, entitled “Method, Apparatus, and Nut for Preloading A Bearing”, now U.S. Pat. No. 9,200,672 issued on Dec. 1, 2015, (Attorney Docket No. 0545.051D), the entire disclosure of which is incorporated herein by reference. 
     This application also relates to U.S. Ser. No. 14/814,086, filed Jul. 30, 2015, entitled “Apparatus for Preloading A Bearing”, now U.S. Pat. No. 9,618,049 issued on Apr. 11, 2017, (Attorney Docket No. 0545.051E), the entire disclosure of which is incorporated herein by reference. 
     This application also relates to U.S. Ser. No. 14/852,100, filed Sep. 11, 2015, entitled “Method, Apparatus, and Nut for Bearing”, now U.S. Pat. No. 9,651,094 issued on May 16, 2017, (Attorney Docket No. 0545.051F), the entire disclosure of which is incorporated herein by reference. 
     This application also relates to U.S. Ser. No. 14/952,663, filed Nov. 25, 2015, entitled Method, Apparatus, and Nut for Bearing”, now U.S. Pat. No. 9,574,612 issued on Feb. 21, 2017, (Attorney Docket No. 0545.051G), the entire disclosure of which is incorporated herein by reference. 
     This application also relates to U.S. Ser. No. 15/441,520, filed Feb. 24, 2017, entitled “Method for Preloading a Bearing”, now U.S. Pat. No. 9,797,441 issued on Oct. 24, 2017, (Attorney Docket No. 0545.051H), the entire disclosure of which is incorporated herein by reference. 
     This application also relates to U.S. Ser. No. 15/714, filed Sep. 25, 2017, entitled “Apparatus for Preloading a Bearing”, (Attorney Docket No. 0545.0511), the entire disclosure of which is incorporated herein by reference. 
     This application is also related to U.S. Ser. No. 14/533,143, filed on Aug. 8, 2014, entitled “Systems and Methods for Preloading a Bearing and Aligning a Lock Nut”, now U.S. Pat. No. 9,217,461 issued on Dec. 22, 2015, (Attorney Docket No. 0545.092A), the entire disclosure of which is incorporated by reference); 
     This application is also related to U.S. Ser. No. 14/946,168, filed on Nov. 19, 2015, entitled “Systems and Methods for Preloading a Bearing and Aligning a Lock Nut”, now U.S. Pat. No. 9,587,667 issued on Mar. 7, 2017, (Attorney Docket No. 0545.092B), the entire disclosure of which is incorporated by reference); 
     This application is also related to U.S. Ser. No. 15/418,315, filed on Jan. 27, 2017, entitled “Systems and Methods for Preloading a Bearing and Aligning a Lock Nut”, published as U.S. Publication No. US-2017-0152883-A1 on Jun. 1, 2017, (Attorney Docket No. 0545.092C), the entire disclosure of which is incorporated by reference); 
     This application is also related to U.S. Ser. No. 15/880,008, filed on Jan. 25, 2018, entitled “Systems and Methods for Preloading a Bearing and Aligning a Lock Nut”, (Attorney Docket No. 0545.092D), the entire disclosure of which is incorporated by reference); 
     This application also relates to U.S. Ser. No. 15/071,584, filed Mar. 16, 2016, entitled “Systems and Methods for Preloading a Bearing”, now U.S. Pat. No. 9,599,164 issued on Mar. 21, 2017, (Attorney Docket No. 0545.106), the entire disclosure of which is incorporated herein by reference. 
     This application also relates to U.S. Ser. No. 15/416,683, filed Jan. 26, 2017, entitled “Systems and Methods for Preloading a Bearing”, published as U.S. Publication No. US-2017-0268572-A1 on Sep. 21, 2017, (Attorney Docket No. 0545.106B), the entire disclosure of which is incorporated herein by reference. 
     This application also relates to U.S. Ser. No. 15/071,753, filed Mar. 16, 2016 entitled “System and Methods for Preloading a Bearing”, now U.S. Pat. No. 9,764,453 issued on Sep. 19, 2017, (Attorney Docket No. 0545.107), the entire disclosure of which is incorporated herein by reference. 
     This application also relates to U.S. Ser. No. 15/661,808, filed Jul. 27, 2017, entitled “Systems and Methods for Preloading a Bearing”, published as U.S. Publication No. US-2017-0320203-A1 on Nov. 9, 2017, (Attorney Docket No. 0545.107A), the entire disclosure of which is incorporated herein by reference. 
    
    
     TECHNICAL FIELD 
     The present invention relates, generally, to methods and apparatus for preloading antifriction bearings in drive trains, particularly, to preloading and adjusting bearings while monitoring the preload being applied. 
     BACKGROUND OF THE INVENTION 
     Various means have been devised to simplify the adjustment of axle bearings, specifically, truck axle bearings. It is generally accepted that in some bearing installations, for example, axle bearings, the life of the bearing will be optimized if the adjustment is made for a slight axial compressive deflection, for example, about 0.003 inches (where this amount is the compressive deflection of the two bearings combined), which is often referred to as “a three thousandths preload.” Typical prior art methods of creating these preloads are obtained by applying specified torques to the bearing assembly, for example, by tightening the nut that retains the bearings. However, for several reasons, it is typically extremely difficult to achieve such preload settings under actual in-field conditions, such as in a mechanic shop. For example, the assembly of a heavy truck wheel onto a wheel hub assembly is a relatively cumbersome procedure that hinders the mechanic. Moreover, the wheel hub assembly always includes at least one inner seal, usually a lip type of seal, which can impose a resistive drag torque component to the preload torque, particularly when the seal is new. 
     Lock nut systems are often utilized to retain a wheel or hub assembly, including axle bearings, on a shaft. Such lock nut systems may be connected to a shaft and inhibit rotation of a retaining nut relative to such shafts. For example, such systems are often utilized on motor vehicles, such as axles and wheel ends. Typically, a lock nut will be engageable with a locking member or keeper which inhibits movement of the nut relative to the shaft. The locking member may include a protruding portion which extends into a slot or receiving portion of a shaft. The locking member may also engage the nut such that there is little or no movement between the nut and shaft. 
     It is important that teeth of a locking member engage teeth of the lock nut such that the locking member is positioned to allow it to engage a slot of the shaft. The nut must be aligned to allow such engagement by selective rotation of the nut to a particular position such that the teeth of the nut and the teeth of the locking member when engaged allow an engaging portion of the locking member to engage a slot of the shaft. Rotation of the nut may be performed during the preloading of a bearing and the degree of rotation allowed may depend on the amount of compressive force applied to a bearing or hub during the preloading of the bearing and the method of application of such force. 
     Thus, a need exists for providing accurate and repeatable procedures and devices for providing and adjusting bearing preload and for adjusting lock nut systems configured to retain preloaded bearings. 
     SUMMARY OF THE INVENTION 
     The present inventor provides, in a first aspect, an apparatus for providing a load on a bearing mounted to a shaft which includes an attaching member releasably connectable to the shaft. A press mechanism is coupled to the attaching member and is configured to provide a compressive load to the bearing. An optical sending unit is configured to output a high intensity light to allow a user to locate a shaft slot of the shaft to align the press mechanism relative to the shaft when the attaching member connects to the shaft. 
     The present invention provides, in a second aspect, a method for use in providing a load on a bearing mounted to a shaft which includes mounting an attaching mechanism to an end of the shaft. A press mechanism is coupled to the attaching member and is configured to provide a compressive load to the bearing. A high intensity light is directed from a sending unit towards the shaft. A shaft slot of the shaft is aligned with the light beam to align the press mechanism relative to the shaft. 
     The present invention provides, in a third aspect, an apparatus for providing a load on a bearing mounted to a shaft which includes an attaching member releasably connectable to the shaft. A press mechanism is coupled to the attaching member and is configured to provide a compressive load to the bearing. The press mechanism includes a wrench engageable with a lock nut on the shaft and is configured to rotate the nut when the attaching member connects to the shaft. 
     The present invention provides, in a fourth aspect, a method for use in providing a load on a bearing mounted to a shaft which includes mounting an attaching mechanism to an end of the shaft. A press mechanism is coupled to the attaching member and is configured to provide a compressive load to the bearing. A wrench of the press mechanism is engaged with the lock nut on the shaft and the wrench rotates the nut. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The subject matter, which is regarded as the invention, is particularly pointed out and distinctly claimed in the claims at the conclusion of the specification. The foregoing and other objects, features, and advantages of the invention will be readily understood from the following detailed description of aspects of the invention taken in conjunction with the accompanying drawings in which: 
         FIG. 1  is a right side elevation view, partially in cross section, of a wheel hub assembly engaging a bearing preload apparatus according to one aspect of the invention; 
         FIG. 2  is a close up view of a portion of  FIG. 1 ; 
         FIG. 3  is a top plan view, partially in cross section of a portion of the assembly shown in  FIG. 1 ; 
         FIG. 4  is an exploded perspective view of the assembly of  FIG. 1  with portions of the wheel hub assembly removed; 
         FIG. 5  is perspective view of the assembly of  FIG. 1  with portions of the wheel hub assembly removed; 
         FIG. 6  is a perspective view of the apparatus of  FIG. 5  with extending arms of the preload apparatus extended relative to the depiction in  FIG. 5 ; 
         FIG. 7  is a perspective view of the apparatus of  FIG. 6  with the extending arms extended further around a lock nut to engage a bearing; 
         FIG. 8  is an elevational view of a lock nut system which includes a lock nut having a keeper and a keeper retaining member engaged with the nut according to an aspect of the present invention; 
         FIG. 9  is an elevational view of the keeper retaining member of  FIG. 8 ; 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     In accordance with the principals of the present invention, system and methods for adjusting bearings mounted on a shaft and aligning lock nuts for retaining such bearings are provided. 
     In an exemplary embodiment depicted in  FIG. 1 , a wheel hub assembly  10  engages a bearing preload apparatus  20 . Some of a section of the hardware has been removed to reveal inner structure to facilitate disclosure of the invention. For the sake of illustration, the wheel assembly that would typically be mounted to wheel hub assembly  10  is omitted in these figures. 
     Wheel hub assembly  10  is an assembly that would typically be found on a front or rear axle of a cab or tractor of a tractor-trailer, or an axle of a trailer. However, aspects of the invention are not limited to use for vehicle bearings. As will generally be understood by those skilled in the art, aspects of the invention may be used to service bearings and bearing assemblies in any machine or device that employs bearings, including, but not limited to: power trains, transmissions, machine components, on and off-road vehicles, aircraft wheels, marine drives, spacecraft, conveyor rolls, and windmills, among others. According to aspects of the present invention, preload apparatus  20  may be used in these and any other assembly for which bearing preload and/or endplay is desired, for example, any assembly that utilizes thrust and radial load carrying bearings that are indirectly mounted. 
     As shown in  FIG. 1-4 , for example, wheel hub assembly  10  includes a wheel hub or, simply, a hub  12 , a threaded shaft, axle, or spindle  14 . As is typical, spindle  14  is mounted on two antifriction bearings and spindle  14  includes an exposed end  13 , which is typically threaded. Spindle  14  typically includes a retaining nut  11  threaded to exposed end  13 . 
     As shown in  FIGS. 1-3 , as is typical of bearings, an outboard bearing  16  includes an inner race (or cone)  15 , an outer race (or cup)  17 , a plurality of rollers  22 , and a roller cage. Similarly, an inboard bearing  18  includes an inner race (or cone)  19 , an outer race (or cup)  21 , a plurality of rollers  26 , and roller cage. As shown in  FIG. 2 , outboard bearing  16  is positioned, for example, by an interference fit, into an annular cavity  29 . The details of an inboard bearing and an outboard bearing are described and depicted in co-owned U.S. Pat. No. 7,303,367, issued Dec. 4, 2007 (application Ser. No. 11/029,531 filed Jan. 5, 2005), entitled “Lock Nut System”; U.S. Pat. No. 7,559,135, issued Jul. 14, 2009 (application Ser. No. 11/341,948 filed Jan. 27, 2006), entitled “Method and Apparatus for Preloading a Bearing”; and U.S. Pat. No. 7,389,579, issued Jun. 24, 2008 (application Ser. No. 11/354,513, filed Feb. 15, 2006), entitled “Method, Apparatus, and Nut for Preloading a Bearing”, the entirety of which are incorporated herein by reference. 
     As depicted in  FIGS. 1-8 , for example, retaining nut  11  may be a locking nut as disclosed in co-owned U.S. Pat. No. 7,303,367 (application Ser. No. 11/029,531 filed Jan. 5, 2005), entitled “Lock Nut System”; U.S. Pat. No. 7,559,135, issued Jul. 14, 2009 (application Ser. No. 11/341,948 filed Jan. 27, 2006), entitled “Method and Apparatus for Preloading a Bearing”; and U.S. Pat. No. 7,389,579 (application Ser. No. 11/354,513, filed Feb. 15, 2006), entitled “Method, Apparatus, and Nut for Preloading a Bearing”. In the conventional art, retaining nut  11  typically is used to secure a wheel (not shown) or hub assembly to a non-rotating axle or spindle  14 . However, in aspects of the present invention, retaining nut  11  may be useful in varying the preload and/or endplay of bearing  16 . Though bearing  16  is illustrated as a tapered roller bearing, aspects of the invention may be applied to other types of antifriction bearings for which it is desirable to provide preload and/or endplay, for example, spherical roller bearings, deep groove ball bearings, and the like. 
     As depicted in  FIGS. 8-9 , a keeper  530  is engageable with retaining nut  11  and is connected to a keeper retaining member  540 . A projection  535  of keeper  530  extends through an opening  545  in retaining member  540  when connected. Projection  535  extends substantially perpendicular to a plane of retaining member  540 . Projection  535  may be deformed by pressure applied on a top thereof (i.e. in a direction substantially perpendicular to the plane of retaining member  540 ) to connect retaining member  540  with keeper  530  similar to the way a rivet is utilized, as will be understood by those skilled in the art. Keeper  530  and retaining member  540  engage retaining nut  11 . For example, keeper  530  includes keeper teeth  520  which are configured to engage engaging teeth  511  of retaining nut  11 . Keeper  530  may also include an engaging member  534  which protrudes radially inwardly relative to retaining nut  11  to engage a shaft slot  5  ( FIG. 4 ), keyway, groove or other engaging portion of a shaft (e.g., spindle  14 ). Thus, engaging member  534  may inhibit movement of keeper  530  relative to a shaft (e.g., spindle  14 ) and the engagement of engaging teeth  511  with keeper teeth  520  may inhibit movement of keeper  530  relative to retaining nut  11 . Accordingly, movement of retaining nut  11  relative to the shaft is prevented or reduced. Keeper  530  and/or nut  11  may be molded or formed of powdered metal, for example. 
     Keeper retaining member  540  may engage a slot  561  of retaining nut  11 . For example, a first leg  542  and a second leg  543  may be received in slot  561 . For example, slot  561  may have a radial depth of about 0.050 inches. Further, a nose  544  of retaining member  540  may be received in slot  561 . Retaining member  540  when received in slot  561  may align keeper  530  such that keeper teeth  532  are engaged with engaging teeth  511 . Further, retaining member  540  provides resistance in an axial direction relative to retaining nut  11  thereby inhibiting movement of keeper  530  axially away from a shoulder  524  toward an outer surface  522 . 
     Retaining member  540  may be elastically deformable to allow it to be received in slot  561 . For example, first leg  542  and second leg  543  may be deformed (e.g., in a direction substantially perpendicular to the axis of retaining nut  11 ) toward one another prior to being inserted axially past outer surface  522  of retaining nut  11  to allow retaining member  540 , and keeper  530  to be attached thereto. First leg  542  and second leg  543  may then be elastically returned toward slot  561 . First leg  542  may also include a gripping member  568  and second leg  543  may include a second gripping member  569 . The gripping members are substantially parallel to one another and are aligned at about 90 degrees from a plane of retaining member  540 . A user may move the legs (i.e., first leg  542  and second leg  543 ) toward one another as described above to allow the retaining member to be received in slot  561 . In one example, a user may use a tool (e.g., a tool made for this specific purpose or a type of pliers such as needle nose pliers) which is inserted into openings  611  and  612  ( FIG. 5 ) to allow the tool to grip the legs to move ends  610  toward one another thereby allowing the legs to be inserted into slot  561 . In an example a tool, such as a tool  7  disclosed in co-owned U.S. Pat. No. 9,599,164 issued on Mar. 21, 2017, entitled “Systems and Methods for Preloading a Bearing” (Attorney Docket No. 0545.106), could be utilized to grip the legs. 
     Also, first leg  542  may include a protruding portion  560  which protrudes radially relative to a rounded portion  565  of retaining member  540 . Similarly, second leg  543  may include a protruding portion  562 . Protruding portion  560  and protruding portion  565  may extend into slot  561  to engage retaining member  540  with slot  561 . Further, protruding portion  560  may include a groove  566  and protruding portion  562  may include a groove  567 . For example, retaining member  540  may be formed of stamped sheet metal, and may have a thickness in a range between 0.040-0.050 inches, as will be understood by those skilled in the art. Alternatively, retaining member  540  could be formed of other materials (e.g., powdered metal) and/or formed in other shapes to allow retaining member  540  to be received in slot  561  and to be connected to keeper  540  via projection  535 . Further, keeper  530  may be formed or molded of powdered metal, for example. Alternatively, keeper  530  and retaining member  540  could be formed integral or monolithic relative to one another. 
     Further, keeper  530  and/or nut  11  may be fabricated from any one or more of the structural metals, for example, carbon steel or stainless steel. Nut  11  may be fabricated by machining from a billet or plate, by forging or casting and then finished machining, or fabricated by conventional powder metallurgy techniques. In one aspect, when formed by powder metallurgy, the material may be FC  0208 , or its equivalent. Nut  11  may also be surface hardened for example, induction hardened, carburized, or nitrided, among other surface hardening methods; in one aspect, the exposed surfaces on end  241  of nut  220  may be hardened, for example, induction hardened. 
     Returning to  FIGS. 1-5 , preload apparatus  20  includes an attaching mechanism, such as a shaft or rod  40  engageable with spindle  14  by a collar  46 , and a press mechanism  44  for providing a compressive load to bearing  16 . In addition, aspects of the invention provide means for monitoring the preload on the bearings to, for example, ensure that the desired preload is provided, in contrast to the unreliable and often inaccurate assumed preloading of the prior art. 
     Rod  40  may be configured to attach to exposed end  13  of shaft  14 , for example, by collar  46 , though other attachment means may be used. Press mechanism  44  may include an adjustment handle  50  which may be connected to rod  40  to facilitate rotation of rod  40  and/or collar  46  to connect press mechanism  44  to shaft  14 . Such connection may also be performed by a servo motor or other mechanism for rotating rod  40  and/or collar  46  to connect press mechanism  44  to shaft  14 . Press mechanism  44  may provide a compression force via a nut as described in co-owned U.S. Pat. No. 8,316,530 relative to nut  48  depicted therein or via a hydraulic, pneumatic or other means of providing such a force. 
     As shown in  FIGS. 3-7 , press mechanism  44  includes loading arms  210 . A compressive load from press mechanism  44 ) is transmitted to bearing  16 , and to bearing  18 , by loading arms  210 . Further, loading arms  210  work in conjunction with retaining nut  11  to provide a load to outboard bearing  16  (e.g., an inner race  15  thereof). Retaining nut  11  may have a recess that exposes the surface of inner race  15  and permits contact by, for example, loading arms  210 . For example, as depicted in  FIGS. 1-7 , nut  11  may have a bottom curve or recessed portion  111  such that a bottom end of nut  11  has a smaller diameter than the remainder thereof. Loading arms  210  may thus transmit the compressive load from press mechanism  44  (i.e., around nut  11 ) to bearing  16 . In an unillustrated example, bearing  16  could be exposed thereby allowing press mechanism  44  to be used with a conventional axle nut, as shown for example in  FIG. 3  of co-owned application, U.S. Pat. No. 7,389,579 issued Jun. 24, 2008 (application Ser. No. 11/354,513, filed Feb. 15, 2006), and entitled “Method, Apparatus, And Nut For Preloading A Bearing”. However, when bearing  16  would be concealed by such a conventional axle nut, retaining nut  11  may be used instead thereof according to aspects of the invention. 
     As depicted in  FIGS. 3-7 , for example, loading arms  210  extend from a base  400  and include a first arm  212  and a second arm  213 . In this aspect of the invention, arms  210  are adapted to transmit a load from press mechanism  44  to bearing  16 . In one aspect, arms  210  may be moveable or deflectable to facilitate assembly of arms  210  into engagement with bearing  16 . For example, arms  210  may include a modification to arms  212  and  213  that permits arms  212  and  213  to deflect to avoid interference with nut  11 . 
     Arms  210  may be pivotally mounted to base  400  or another portion of press mechanism  44  (to allow lateral movement of the arms such that the arms may engage bearing  16 ). Arms  210  may include projections  225 ,  226 , respectively, for example, arcuate projections adapted to engage the arcuate shape of bearing  16  (e.g., an inner race thereof) as described previously relative to extensions  212 ,  213  of co-owned U.S. Pat. No. 8,650,757 issued on Feb. 18, 2014 (U.S. Ser. No. 13/683,571, filed Nov. 21, 2012 for “Systems and Methods for Preloading a Bearing and Aligning a Lock Nut” (Attorney Docket No. 0545.057A). Arcuate projections  225 ,  226  may be radiused to provide the same curvature of bearing  16 , for example, a radius of between about 1¼ inches and about 3 inches. The shape of arms  210  including projections  225 ,  226  may ensure that the compressive load applied by press mechanism  44  is transmitted to bearing  16  and not borne by nut  11 . Minimizing or preventing contact between extensions  212 ,  213  and nut  11  also permits nut  11  to be freely rotated without contact with extensions  212 ,  213 . 
     Although only two arms  212 ,  213  are illustrated in  FIGS. 3 and 10-11 , according to one aspect of the invention, two or more arms  212 ,  213  may be mounted to, or otherwise extend from, base  400  of press mechanism  44 . For example, three or more extensions arms may be provided, for example, uniformly spaced about base  400  about an axis coaxial to an axis of shaft  14  and/or rod  40 . In one aspect of the invention, arms  212 ,  213  may include spring-loaded mountings to base  400  whereby arms  212 ,  213  are biased into a position of engagement with race  15 . 
     Press mechanism  44  may include a wrench  230  having teeth  235  engageable with teeth  511  of nut  11  to allow a rotation of nut  11  via a controller (not shown) controlling a rotation of nut  230 . Wrench  230  may surround collar  46  and may be extendable away from base  400  toward nut  11  and retractable in an opposite direction. Teeth  235  may engage teeth  511  when wrench  230  is extended to contact nut  11 . For example, wrench  230  may be driven by a servo motor coupled to the controller to control rotation of wrench  230  and thus nut  11  while wrench  230  may also be extendable to engage nut  11  via a servo motor coupled to, and controlled by, the controller. The rotation and extension of wrench  230  could also be driven by a hydraulic or pneumatic system including a pump controller by the controller utilizing a rack-and-pinion system, for example. 
     Press mechanism  44  may also include a housing  430  having slot optical sending units  410  and configured to help a user align shaft slot  5  ( FIG. 3 ) of spindle  14  with press mechanism  44 , for example, as depicted in  FIGS. 1-4 . Optical sending units  410  may provide a high intensity light source, such as a laser beam. 
     High intensity light beams, such as laser beams, emitted from the sending units may be aligned with opposite circumferential sides of shaft slot  5 , for example, by rotating housing  430  relative to base  400 . A locking mechanism  412  may be engaged by a user when beams of light produced by the sending units are aligned as described to maintain housing  430 , and thus the beams of light, in a particular position. 
     Press mechanism  44  may also include locating optical sending units  420  located on circumferential opposite sides of housing  430  of press mechanism  44  relative to optical sending units  410 . Locating light or laser beams produced by locating optical sending units  420  may be utilized by a user as a reference point relative to retaining nut  11 . In particular, retaining nut  11  may include one or more markings  510  corresponding to one or more roots  512  (i.e., low points equidistant between each pair of engaging teeth) of engaging teeth  511  thereof as depicted in  FIG. 8 . For example, the markings may be circular indentations in the nut. The location of such markings on outside surface  522  of nut  11  allows a user to selectively rotate the nut relative to the locating laser light or beams produced by locating optical sending units  420  (e.g., when pressure is applied to bearing  16  by press mechanism  44  to allow rotation of nut  11 ) to an engaging position where the locating laser beams are at desired positions relative to one or more of markings  510 . In such position, engaging teeth  511  may be properly engaged with keeper teeth  520  such that radially inner side  534  engages shaft slot  5  of spindle  14 , i.e., after preload apparatus is removed and keeper  530  and keeper retaining member  540  engage nut  11 . Further, keeper retaining member  540  may include a notch  541  in a nose  544  thereof with the notch being located at about a geometrical central point of keeper retaining member  540  (e.g., on an axis of symmetry thereof) such that an equal amount of retaining member  540 , such as first leg  542 , is one side thereof while the remainder of retaining member  540 , such as second leg  543 , is on another side thereof. Further, keeper  530  may be centered on keeper retaining member  540  such that a central engaging tooth (e.g., a central engaging tooth  570  as disclosed in co-owned U.S. Pat. No. 8,650,757) is aligned with notch  541 . Also, retaining member  540  may be placed in slot  561  such that the central engaging tooth engages a tooth root aligned with a marking of markings  510  to which notch  541  is aligned. Alternatively, markings  510  could correspond to a different feature of nut  11  (i.e., besides the roots between teeth  511 ) to facilitate the engagement of nut  11  with keeper  530  and/or keeper  530  with shaft slot  5  of spindle  14 . 
     In another example, an optical receiver may receive a reflection of light produced by optical sending units  410  and/or  420  to determine a point that the laser beams produced thereby contact nut  11  and the locations of the markings on nut  11 . Press mechanism  44  may include, or be connected to, a controller coupled to optical sending units  410  and/or  420  and the receiver, along with wrench  230  and/or a separate wrench (not shown) usable to rotate nut  11 . The controller may cause the rotation of nut  11  to a desired preload and based on the locations of the light or laser beam(s) to allow the proper engagement of engaging teeth  511  with keeper teeth  520  as described above, and such that radially inner side  534  of keeper  530  engages shaft slot  5  when retaining member  540  is placed in slot  561  as described above. 
     Press mechanism  44  may be any apparatus that is configured to provide a compressive load (e.g., utilizing nut  48  as disclosed in patent &#39;530) to outboard bearing  16  (e.g., an inner race thereof). Further, press mechanism  44  may include a load sensor or any means for monitoring the compressive load transferred to bearing  16 . For example, an indication of the compressive load transferred by press mechanism  44  may be provided mechanically, for example, by compression springs having a known spring constant, for example, coil springs or disc springs, and a deflection indicator, for example, a dial indicator, as is known in the art. In this aspect, a dial indicator may be mounted to detect and indicate the compression of one or more springs positioned in press mechanism  44  due to the advancement of nut  48 , and the compression load calculated from the deflection indicated and the known spring constant of the springs used. This aspect of the invention may provide a reliable and repeatable means for monitoring the preload provided to inner race  15  of outboard bearing  16 . The load sensor may be wired to an appropriate controller or processor and display to, for example, provide a digital readout of the compressive load to the mechanic operating preload device  20 . The transmission of signals from the sensor may also be practiced wirelessly, for example, by means of an RF signal. This aspect of the invention may also provide a reliable and repeatable means for monitoring the preload provided to bearing  16 . 
     In another aspect of the invention, press mechanism  44  may include at least one fluid, for example, a gas, such as air; or a liquid, such as, water, oil, or hydraulic fluid, the pressure of which can be detected and monitored, for example, by means of a pressure gage, pressure sensor, or a mechanical indicator. In one aspect not illustrated, the fluid pressure may comprise the source of compressive load on bearing  16 . In such an embodiment, the fluid may be retained in a cavity for example, a deformable cavity, such as a bladder or hose, for example, an air spring; or a cavity having rigid walls and at least one moveable wall, for example, as in a cylinder and piston. In one aspect, the deformable cavity or air spring may be made of molded rubber, somewhat like an inner tube. 
     When air is used as the fluid, the air may be provided by conventional “shop air” at a pressure of about 100 psig. The pressure of the fluid in the deformable cavity may be monitored by means of sensor or pressure gage, for example, a pressure gauge mounted to a nozzle inserted the wall of the deformable or non-deformable cavity. In one aspect, a mechanical indicator may be activated, for example, a lever deflected when the desired fluid pressure in press mechanism  44  is reached advising the mechanic. 
     As discussed previously, press mechanism  44  and rod  40  thereof may be adapted to attach to exposed end  13  of spindle  14 . Though this may be effected by many conventional means, including welding and mechanical fasteners, in the aspect of the invention shown in  FIGS. 1-4 , rod  40  is attached to end  13  of spindle  14  by collar  46 . In the aspect shown, collar  46  is mounted to rod  40  by means of internal threads  47  in collar  46  that thread onto external threads  49  on rod  40 . Collar  46  also includes a second set of internal threads  45  that engage external threads  51  on spindle  14 . In one aspect, only 2 or 3 external threads  51  need be engaged by collar  46 . According to one aspect, multiple collars  46  having varying diameters may be provided to accommodate varying diameters of spindle  14 . Each of these collars  46  may be adapted to engage external threads  49  on rod  40 . 
     Rod  40 , housing  42 , collar  46 , nut  48 , arms  50 , housing  52 , piston  54 , and housing  42  may be fabricated from any conventional structural metal, for example, iron, steel, stainless steel, aluminum, titanium, nickel, magnesium, brass, or bronze, among others. 
     In one aspect of the invention, preload apparatus  20  may be used to apply and monitor a preload to outboard bearing  16 . In a typical procedure, a wheel (not shown) may be dismounted from hub assembly  10 , for example, which was mounted to studs on hub  12 , as exemplified by stud  100  in  FIGS. 1-3 . Nut  11  may be loosened or hand tightened prior to mounting apparatus  20 , though any light load on nut  11  will typically be relieved with application of tension to spindle  14  by means of rod  40 . 
     For example, a torque wrench and socket may be utilized to torque nut  11  and seat the bearings. The nut may then be tightened to a “hand tight” position followed by loosening of the nut by backing it off about ¼ turn. Alternatively, such tightening and loosening may be done using servo controlled wrench tools (e.g., wrench  230 ) which perform such tasks in response to a command by a user or which may be automatically performed in response to a set of instructions programmed and stored in the controller or a second controller or computer storage coupled to the controller. 
     Apparatus  20  may then be mounted to hub assembly  10  by attaching rod  40  to spindle  14  by means of collar  46 . Arms  210  may then be automatically advanced by press mechanism  44  such that the arms are brought into contact with bearing  16  (e.g., an inner race thereof) as depicted in  FIGS. 5-7  which a movement of arms  210  toward bearing  16  and around nut  11 .  FIG. 7  shows a same position of arms  210  as  FIG. 3 . In one example, press mechanism may then apply 4000 lbs force to the bearings. 
     Such force may be generated and transmitted by press mechanism  44  by any of various mechanisms including those described in co-owned U.S. Pat. No. 8,316,530 relative to press mechanism  44 . In one example, disclosed in this patent the loading of bearing  16  may be initiated by advancing, that, is tightening, a nut (such as nut  48  described in this patent), against housing  52  via bearing  62 , for example, by means of arms  50 . The build up of pressure in cavity  56  (as indicated by pressure indicator  60 ) may be monitored by a mechanic, e.g., using a pressure indicator as described in the patent. 
     Pressure may be applied by press mechanism  44  until a target pressure is achieved. The hub assembly may be rotated at least once to provide proper seating of the rollers in bearing  16 . Alternatively, the bearings could be automatically rolled utilizing a separate bearing rolling mechanism not described herein. For example, rod  40  and handle  50  may be rotated three revolutions and such handle may then be counter-rotated slightly to arrive at a desired pressure as indicated on a pressure sensor (not shown). 
     A desired preload may then be provided (e.g., automatically controlled by the controller) by press mechanism  44  to the bearings. The controller may cause a servo motor to actuate wrench tools (e.g., wrench  230 ) and torque the nut (e.g., nut  11 ) to “finger tight” or wrench  230  could be controlled by a controller to provide such a preload. If endplay is desired, a servo motor (e.g., coupled to wrench  230  or a separate servo wrench) may back the nut off to a desired endplay setting. Upon completion of the preloading, apparatus  20  may be removed from wheel hub assembly  10 , and keeper  530  and retaining member  540  may be engaged with retaining nut  11  and spindle  14 , such that keeper teeth  520  engage teeth  511  of nut  11  and engaging member  534  of keeper  530  engage shaft slot  5  of spindle  14 . 
     The preloading of the bearings as described above is advantageous relative to endplay adjustment but was rarely recommended prior to the present invention due to the difficulty of creating and verifying a correct preload site. A load sensor such as a pressure indicator or gauge (not shown) may be used along with the selective positioning of retaining nut  11  on spindle  14  (e.g., using locating laser or light beams produced by locating optical sending units  420  and markings  510 ; or wrench  220  controlled by a controller) provide for a repeatable correct and accurate preload setting. 
     In another example, press mechanism  44  may apply pressure by fluid pressure to provide the compressive load to bearing  16 . In this aspect of the invention, the compressive force provided by the nut described relative to patent &#39;530 may be replaced by fluid pressure provided to press mechanism  44 . For example, as depicted in  FIGS. 1-4 , press mechanism  44  includes a housing  52  and a movable piston  54  mounted for axial movement in housing  52 . In this aspect of the invention, an internal cavity  56  is provided in housing  52 . Internal cavity  56  is at least partially filled, for example, substantially completely filled, with a fluid, for example, a gas, air, oil, water, and the like, that produces a hydrostatic pressure when fluid pressure is provided to internal cavity  56  receiving piston  54  via a pump (not shown), pressurized shop gas, or otherwise. Such pressure may cause movement of piston  54  which may be mechanically coupled to arms  210  to provide the load to bearing  16 . A reduction in such pressure may cause a retraction of piston  54  and/or a reduction in the load. 
     Piston  54  may be provided with one or more seals (not shown), for example, one or more wiper seals, to minimize or prevent the leakage of fluid from housing  52 . Also, cavity  56  bounded by housing  52  may provide clearance for the displacement of piston  54  therein. 
     In one aspect, the fluid pressure (e.g., to cavity  56  of housing  52  of press mechanism  44 ) may be provided by a conduit or hose. The hose may supply fluid, for example, hydraulic fluid, from a pressurized supply, for example, a pump controlled by a controller. The fluid supplied to the hose may vary from 500 to 3000 psig. 
     Such a press mechanism applying pressure by fluid pressure may be used to automatically regulate the compressive load on bearing  16 , for example, by regulating the pressure introduced to press mechanism  44  through the hose. In one aspect, the invention may include an automatic controller, for example, a PID controller, personal computer, or PLC controller adapted to regulate the pressure in the hose. For example, the predetermined preload and the parameters of the bearing being loaded may be entered into the controller and, after mounting a rod similar to rod  40 , housing  42  and a press mechanism to bearing  16  (e.g., an inner race thereof), the controller may automatically ramp up the fluid pressure to provide the desired preload or to verify an existing preload. This aspect of the invention may be suitable for production line applications, among others. 
     In one aspect, the fluid provided by the hose may be provided by a pressure increasing device, for example, a pressure intensifier, that is, a device that converts one pressure to a higher pressure. For example, the pressure-increasing device may be provided with a pressure supply of, for example, 100 psig (for instance, shop air) and increased to, for example, 2000 psig hydraulic fluid, which is then supplied to the hose. Other sources of high-pressure fluid may be provided according to aspects of the invention. 
     In an example, press mechanism  44  may include a switch  300  for use in controlling the load on bearing  16  as described for example in co-owned U.S. Pat. No. 9,764,453 issued on Sep. 19, 2017, entitled “System and Methods for Preloading a Bearing” (Attorney Docket No. 0545.107). Such a switch may be in fluid communication with cavity  56  and thereby a source of fluid (e.g., via the hose described above) utilized to provide fluid pressure to apply the load to the bearing. The switch may be coupled to a controller or may include a controller therein to regulate the compressive load on bearing  16 , for example, by regulating the pressure (e.g., hydraulic or air) introduced into cavity  56  to drive piston  54  as described above. 
     Aspects of the invention may also be used to evaluate the preload or endplay on an existing bearing or bearing assembly. For example, an existing truck hub assembly may be evaluated for its existing preload and compared to the desired preload, and, if necessary, adjusted accordingly. First, the truck may be jacked up, if needed. (The hub may be allowed to cool, if necessary). Apparatus  20  may then be mounted to bearing  16  and spindle  14  (with reference to  FIGS. 1-3 ) and the press mechanism  44  actuated to introduce tension to spindle  14  and compression to bearing  16 . (The wheel may be removed.) Press mechanism  44  may be regulated to, for example, vary the fluid pressure, to gradually increase the preload on bearing  16 . While the load is increased, a mechanic can repeatedly check the load on or the “tightness” of nut  11 . When nut  11  begins to loosen, the existing preload on bearing  16  has been met or exceeded. A comparison of the actual preload indicated by press mechanism  44 , for example, the fluid pressure, with the desired preload can then be made. Any adjustments to the preload, either higher or lower, can be made according to the procedures described above and in U.S. Pat. No. 7,389,579. 
     Although aspects of the present invention were described above with respect to their application to wheel hub assemblies, for example, truck wheel hub assemblies, it is understood that aspects of the present invention may be applied to any vehicle, machine, or component having at least one bearing. Further, although press mechanism  44  is described above as applying a compressive load to an inner race of a bearing, such load could be applied elsewhere to the bearing or wheel assembly  10  such that a frictional or other load on a retaining nut is reduced to allow rotation of a retaining nut. Such rotation may allow teeth of the nut and teeth of a keeper to be aligned with each other to allow engagement of a shaft engaging portion of the keeper with a shaft, (e.g., a shaft slot thereof) to inhibit rotation of the nut relative to the shaft. 
     While several aspects of the present invention have been described and depicted herein, alternative aspects may be effected by those skilled in the art to accomplish the same objectives. Accordingly, it is intended by the appended claims to cover all such alternative aspects as fall within the true spirit and scope of the invention.