Abstract:
A spline rolling rack assembly for cold-forming external surface configurations upon a metal workpiece is provided, having a durable carriage of the type secured upon a reciprocating slide assembly, a perishable rack insert that is removably secured upon the carriage, a locating key disposed between the rack insert and the carriage for properly aligning the rack insert upon the carriage, a locating assembly disposed upon the carriage and engageable with the rack insert for assisting in properly aligning the rack insert and the carriage between load and work positions, and multiple clamping assemblies disposed within said carriage for releasably securing the rack insert upon the carriage. The perishable rack insert is designed for quick and convenient replacement, reducing maintenance cost and idle time for these devices. The single-use nature of the insert relieves the user from the burden of managing an inventory of like tools, in various states of use, in order to ensure that new tools are ordered in a timely manner for replacing tools that have exhausted their useful life.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application is a continuation of U.S. patent application Ser. No. 13/478,663 filed on May 23, 2012. The entire disclosure of the above application is incorporated herein by reference. 
     
    
     FIELD 
       [0002]    The present disclosure relates generally to machines for forming external surface configurations upon metal workpieces by pressure-applied material displacement, and is more specifically directed to spline rolling rack assemblies, components, tooling and devices for securing and manipulating such tooling. The present disclosure also relates to methods for roll-forming splines on the external surfaces of axle, shaft and other power/torque transmission components of the type used in vehicles, machines, commercial and industrial equipment and other devices. 
       BACKGROUND 
       [0003]    This section provides background information related to the present disclosure which is not necessarily prior art. 
         [0004]    The manufacture of axle, shaft and other power/torque transmission components of the type used in vehicles, machines, commercial and industrial equipment and other devices often requires the formation of power/torque transmission features upon the external surfaces of round metal workpieces, in the form of rods, tubes, cylinders and other shapes. One exemplary manufacturing method involves spline rolling, which typically utilizes a pair of opposed, elongated, substantially parallel, reciprocating dies, tools or tool members (called “racks”) having a series of feature-forming surfaces, such as teeth, disposed in precision arrangements on facing surfaces thereof corresponding to, but not necessarily matching, the desired final surface features of the workpiece to be prepared. Accordingly, spline rolling typically involves reciprocating movement of the opposed dies, tools or tool members (called “racks”) over the length of a rotating workpiece, in opposite directions and in overlapping relationship, causing the feature-forming surfaces to displace material upon the surface of the rotating workpiece by applied pressure, in a cold-forming technique. The spline rolling operation thus forms the desired finished external surface features in the workpiece, typically helical or spur ridges, teeth or grooves (or “splines”), through the combination of the rotation of the workpiece with the linear reciprocating movement of the racks. Spline rolling racks are typically constructed in single or double-piece form, with either the single piece or both pieces of a double-piece rack being perishable. They are typically fastened upon suitable opposed, elongated, substantially parallel, reciprocating slide assemblies located within dedicated spline rolling machines of industrial grade. 
         [0005]    The nature of forming the desired power/torque transmission features, such as splines, requires critical tolerances in the size and configuration of the feature-forming surfaces, and well as in the spacing, configuration and movement of the racks so that the desired surface features are accurately formed in the workpiece. Thus, these tooling components require precision-crafted feature-forming surfaces and precision mounting apparatus, supports and fasteners within the larger machines in which they are typically contained. However, these tooling components have a limited lifespan, with their feature-forming surfaces typically becoming worn or no longer within required tolerances after some period of their use. 
         [0006]    Accordingly, at periodic intervals it is typically necessary to remove the surface-forming tooling components for replacement or resurfacing. Such components can typically be resurfaced a number of times before they can no longer be resurfaced, and as such, must then be replaced. Oftentimes, the manufacture and resurfacing of such tooling components is inefficient due to the time required to ship the components back to the manufacturer for resurfacing and back again to the user. Also, oftentimes, removal and replacement of such tooling components is time-consuming, burdensome and otherwise inefficient, due to the configuration and large size of the components, the current way in which the tooling components are secured in a work position, and the positioning and aligning activities that must typically take place for securing the components in a work position. Having such a machine in an idle state during required maintenance activities slows down overall production rates for any such affected facility, so it is advantageous for such maintenance to be made convenient, efficient and quick. 
         [0007]    As examples, the tooling components requiring repair or replacement may be secured within the interior of a larger machine in a way that is inconvenient to manage, such as being secured with fasteners, such as bolts and set screws, that are difficult to reach and manipulate. In addition, the end of a spline rolling rack is typically the primary locating surface for gauging the proper mounting location of the rack within the machine, which can be inconvenient to measure or check for proper alignment. Also, the tooling components may not themselves be manufactured in sufficient tolerances for precision work, or the devices or features provided for facilitating proper positioning may not be sufficient or efficient to use. Proper alignment of the tooling components relative to each other must typically be ensured, which may only be provided in limited scope by relative adjustment of certain surfaces on the machine components when located within the machine that can be difficult to reach and/or examine. The final tolerances required in the feature-forming surfaces may also not be sufficient, or may be manufactured inefficiently, such as by preparing the feature-forming surfaces to required precision tolerances as the final step of the manufacturing process. 
         [0008]    In addition, there is typically a substantial cost associated with the replacement or repair of the tooling components involved in such surface forming operations. The sizes of the components can be substantial, depending upon the sizes of the power/torque transmission components being manufactured, perhaps requiring substantial powered lifting equipment for assisting in this activity. The repair or replacement of the tooling components may require shipment and/or courier delivery of substantially-sized and weighted components, at considerable expense. Users of such tooling components must also manage a float of such tools at various levels of life and, due to the lead time required to manufacture new racks, must anticipate tools ending their life span and order new tools to arrive in conjunction with the retirement of existing tools. 
         [0009]    In consideration of the above, the adoption of an improved configuration of such surface-forming tooling components along with an improved configuration of the associated devices used for retaining such components in required locations while maintaining the required tolerances for same, would provide significant maintenance efficiencies and cost benefits. 
       SUMMARY 
       [0010]    This section provides a general summary of the disclosure, and is not a comprehensive disclosure of its full scope or all of its features. 
         [0011]    The present disclosure provides a spline rolling rack assembly for cold-forming external surface configurations upon a metal workpiece, comprising a durable carriage operable for being fixedly secured upon a reciprocating slide assembly within a machine for forming external surface configurations upon said metal workpiece. The carriage includes a mounting surface and is operable for sliding in reciprocating relation together with rotation of the workpiece. The spline rolling rack assembly further comprises a perishable rack insert that is operable for being removably secured upon said mounting surface of said carriage, the rack insert having a working surface with a series of feature-forming surfaces formed thereupon for cold-forming external surface configurations upon a metal workpiece. The rack insert is operable for being removed from, and secured upon, the carriage within the machine without removing the carriage from within the machine. 
         [0012]    The spline rolling rack assembly further comprises a locating key operable for being disposed between a first locating key recess formed within the rack insert and a second locating key recess formed within the carriage for properly aligning the rack insert upon the carriage in at least one of a load position and a work position. Manufactured configurations of the locating key and the first and second locating key recesses together comprise the primary engaging components and surfaces for properly aligning said rack insert upon said carriage in at least one of a load position and a work position. Also, the locating key may preferably be secured to said carriage by a locating bolt. 
         [0013]    The spline rolling rack assembly further comprises a locating assembly operable for being disposed upon the carriage in movable relation between a first position corresponding to a loading position of the rack insert upon the carriage and a second position corresponding to a work position of the rack insert upon said carriage. The locating assembly is also operable for engaging a recess within the rack insert, wherein movement of the locating assembly from the first position to the second position engages the locating assembly with the recess within the rack insert to assist in properly aligning the rack insert upon the carriage in at least one of a load position and a work position. 
         [0014]    The spline rolling rack assembly further comprises a plurality of clamping assemblies disposed at spaced apart locations longitudinally within the carriage, each clamping assembly operable for releasably contacting the rack insert in a pressurized manner for securing the rack insert in a fixed work position upon the carriage, wherein each clamping assembly is operable for being adjusted between a released unclamped condition and an engaged clamped condition. 
         [0015]    Further areas of applicability will become apparent from the description provided herein. The description and specific examples in this summary are intended for purposes of illustration only and are not intended to limit the scope of the present disclosure. It will be appreciated that the above principles may be applied to devices for forming other types of external surface configurations upon other workpieces as well. 
     
    
     
       DRAWINGS 
         [0016]    The drawings described herein are for illustrative purposes only of selected embodiments and not all possible implementations, and are not intended to limit the scope of the present disclosure. 
           [0017]      FIG. 1  is a front cross-sectional view of the spline rolling carriage and rack insert in an unsecured loading position, according to the present disclosure. 
           [0018]      FIG. 2  is a front cross-sectional view of the spline rolling carriage and rack insert in a secured working position, according to the present disclosure. 
           [0019]      FIG. 3  is a cross-sectional plan view of the spline rolling carriage and rack insert in a secured working position, according to the present disclosure. 
           [0020]      FIG. 4  is a front cross-sectional view of the spline rolling carriage and rack insert in a secured working position, also showing the clamp pins in the secured working position as well as the actuator used to manipulate the insert between the unsecured loading position and secured working position of the associated locating assembly, according to the present disclosure. 
           [0021]      FIG. 5  is an end cross-sectional view of the associated clamping assembly for the spline rolling carriage and rack insert in a secured working position, according to the present disclosure. 
           [0022]      FIG. 6  is an end cross-sectional view of the associated clamping assembly for the spline rolling carriage and rack insert in an unsecured loading or working position, according to the present disclosure. 
           [0023]      FIG. 7  is an end cross-sectional view showing the associated locating assembly for the spline rolling carriage and rack insert, according to the present disclosure. 
           [0024]      FIG. 8  is an end cross-sectional view showing a carriage retention bolt and inner and outer datum rail fasteners for the spline rolling carriage and rack insert, according to the present disclosure. 
           [0025]      FIG. 9A  is an enlarged composite view of the associated locating assembly for the spline rolling carriage and rack insert illustrating its function among multiple positions, according to the present disclosure. 
           [0026]      FIG. 9B  is an enlarged view of the associated locating assembly for the spline rolling carriage and rack insert in a clamped working position, according to the present disclosure. 
           [0027]      FIG. 9C  is an enlarged view of the associated locating assembly for the spline rolling carriage and rack insert in a loading position, according to the present disclosure. 
           [0028]      FIG. 9D  is an enlarged view of the associated locating assembly for the spline rolling carriage and rack insert in an unclamped working position, according to the present disclosure. 
           [0029]      FIG. 10  is an end cross-sectional view of an alternate associated clamping assembly for the spline rolling carriage and rack insert in a secured working position, according to the present disclosure. 
           [0030]      FIG. 11  is an enlarged front cross-sectional view of an alternate associated clamping assembly for the spline rolling carriage and rack insert in a secured working position, according to the present disclosure. 
           [0031]      FIG. 12  is an enlarged view of an alternate associated clamping assembly recess machined directly into the rack insert, according to the present disclosure. 
           [0032]      FIG. 13  is an enlarged view of a locating key for the spline rolling carriage and rack insert in a loading position, as shown in  FIG. 1 , according to the present disclosure. 
           [0033]      FIG. 14  is an enlarged view of a locating key for the spline rolling carriage and rack insert in a secured working position, as shown in  FIG. 2 , according to the present disclosure. 
       
    
    
       [0034]    Corresponding reference numerals indicate corresponding parts throughout the several views of the drawings. 
       DETAILED DESCRIPTION 
       [0035]    Example embodiments will now be described more fully with reference to the accompanying drawings. 
         [0036]      FIG. 1  illustrates a spline rolling rack assembly, generally at  10 , in a loading position, prior to being shifted to the working position illustrated in  FIG. 2 . The spline rolling rack assembly  10  is a component of a larger, dedicated, machine of industrial grade (not shown) for forming external surface configurations, such as helical or spur ridges, teeth or grooves (or “splines”) upon round metal workpieces in the form of rods, tubes, cylinders and other shapes. The spline rolling rack assembly  10  includes a carriage  12  of the type capable of being fixedly secured upon a reciprocating slide assembly (also not shown) within the machine, for sliding in reciprocating relation together with rotation of a workpiece. The carriage  12  is shown to include a carriage mounting surface  14 , as well as a plurality of carriage retention apertures  13 , through which the carriage  12  is secured to the reciprocating slide assembly by a plurality of carriage retention bolts  15 . 
         [0037]    The spline rolling rack assembly  10  also includes a rack insert  16  having a working surface  18  that includes a plurality of feature-forming surfaces, shown in the form of teeth  20 , formed upon the working surface  18 . It will be appreciated that any other suitable feature-forming surfaces may also be formed upon the working surface  18 , depending on the surface configurations desired upon the workpiece. The rack insert  16  is designed to be removably secured upon the carriage mounting surface  14  in a quick and convenient way, without requiring the use of extensive bolts or other individual fasteners. Accordingly, the rack insert  16  is intended to be quickly and conveniently removed from its position upon the carriage  12 , and replaced into its position and secured upon the carriage  12 , whenever repair or replacement of the rack insert  16  is required. The present invention thus provides a dual-component assembly wherein the carriage  12  remains within the larger machine, while only the rack insert  16  is removed and replaced. The configurations and dimensions of the feature-forming surfaces, the carriage  12  and the remainder of the rack insert  16  are manufactured to precision tolerances in configurations and dimensions as may be necessary for creating the required tolerances of configurations and dimensions in the surface configurations being formed upon the workpiece. 
         [0038]    The present arrangement therefore contemplates eliminating use of prior perishable single-piece racks or a double-piece racks wherein both pieces are perishable in favor of a two-piece tooling assembly having a durable carriage supporting a perishable rack insert. Such an arrangement is believed to greatly enhance the convenience and speed for removing and replacing the rack inserts  16 , which in turn will reduce the time that the spline rolling machine is idle for maintenance. In addition, the rack inserts  16  are preferably designed for a single use, although they may also be refinished and reused as many times as permitted by the required specifications and tolerances of the tooling equipment being used and the workpieces being treated. Because the rack inserts  16  can be of significantly smaller dimensions than a single-piece rack of the type common in previous devices, the new rack inserts  16  of the present invention can be handled and shipped much more quickly, more conveniently and at lower cost. 
         [0039]    As shown in  FIGS. 1, 2, 13 and 14 , the spline rolling rack assembly  10  further includes a locating key  22  that is disposed between a first locating key recess  24  formed within the rack insert  16  and a second locating key recess  26  formed within the carriage  12 . The locating key  22  is secured to the carriage  12  by a locating bolt  28 . The locating key recess  24  also includes a primary stop surface  33 , which represents the primary location on the rack insert  16  that bears against the locating key  22 . In the manufacture of a cooperating pair of rack inserts  16 , the working surface  18  of each rack insert  16  is ground to specified tolerances while utilizing each primary stop surface  33  as the primary locating datum for each rack insert  16 , thus ensuring that the rack inserts  16  are synchronized. The locating key  22 , in connection with the first locating key recess  24  and the second locating key recess  26 , together comprise the primary engaging components and surfaces for properly aligning the rack insert  16  upon the carriage mounting surface  14  of the carriage  12  in a load position, as illustrated in  FIGS. 1 and 13 , as well as in a work position, as set forth below in connection with  FIGS. 2 and 14  (wherein the spline rolling rack assembly is referenced at  10  and the rack insert is designated at  16 ′). Accordingly, the manufactured configurations and dimensions of the locating key  22 , the first locating key recess  24  and the second locating key recess  26  are prepared to sufficiently precise tolerances for providing sufficiently precise tolerances in the position of the feature-forming surfaces of the working surface  18  of the rack insert  16 . Use of the locating key  22  is believed to provide a quicker and more easily accessed method for aligning the rack insert  16  upon the carriage  12  than would be possible through other, manual, alignment methods that might rely on visual or tactile inspection of the various component surfaces. 
         [0040]    The spline rolling rack assembly  10  further includes a locating assembly, generally at  30 . The locating assembly  30  includes a lock pin  32  attached to a lock shaft  34  that is rotatably disposed within a first locating assembly recess  36  of the carriage  12 . It will be appreciated that multiple lock pins  32  may be employed, depending on the application. The lock pin  32  extends from the lock shaft  34  outwardly from within the first locating assembly recess  36  of the carriage  12  to within a second locating assembly recess  38  of the rack insert  16 , which forms a stop for movement of the rack insert  16  once it reaches a work position. The lock pin  32  and lock shaft  34  are together capable of being rotated between a first position corresponding to a load position of the rack insert  16  upon the carriage  12  (represented by the position of the lock pin  32  in  FIG. 1 ) and a second position corresponding to a work position of the rack insert  16  upon the carriage (represented by the position of the lock pin  32 ′ in  FIG. 2 ). The counter-clockwise rotation of the lock pin  32  and lock shaft  34  together is accompanied by a longitudinal sliding movement of the rack insert  16  upon the mounting surface  14  of the carriage  12  between a load position for the assembly (represented by the designation  10  in  FIG. 1 ) to a work position for the assembly (represented by the designation  10 ′ in  FIG. 2 ). In similar fashion, the load position and work position for the rack insert are designated as  16  and  16 ′, respectively, in  FIGS. 1 and 2 . Rotation of the lock pin  32  and lock shaft  34  in a clockwise direction (from  32 ′ in  FIGS. 2 to 32  in  FIG. 1 ) returns the assembly from a work position ( 10 ′ in  FIG. 2 ) to a load position ( 10  in  FIG. 1 ) for removal and replacement of the rack insert  16 . Accordingly, the movement of the locating assembly  30  in this manner assists in properly aligning the rack insert  16  upon the carriage  12  between a load position and a work position. Load arrows  35  and  37  are provided in the form of indicia disposed upon, or alternately imprinted into, the external side surfaces of the rack insert  16  and carriage  12 , respectively, for assisting in the alignment of the rack insert  16  upon the carriage  12  in a load position. As shown in  FIG. 2 , movement of the rack insert  16  longitudinally upon the carriage  12  from a load position to a work position displaces the load arrow  35  to the location referenced at  35 ′. Movement of the rack insert  16  from the work position back to the load position realigns the load arrows to ensure that the rack insert  16  is in the proper position for removal from upon the carriage  12 . 
         [0041]      FIGS. 3 and 4  show a cross-sectional plan view and a front cross-sectional view, respectively, of the spline rolling carriage and rack insert of the spline rolling carriage and rack insert in a secured working position. From this view, the carriage retention bolts  15  are shown as being disposed within carriage retention apertures  13 . The carriage retention bolts  15  are operable for securing the carriage  12  to the reciprocating slide assembly (not shown). In addition, there are shown a plurality of inner and outer datum rail fasteners  17  and  19 , which secure the inner and outer datum rails  40  and  42 , respectively, to the carriage  12 . 
         [0042]      FIG. 8  shows in greater detail an end cross-sectional view of a carriage retention bolt  15  disposed through a carriage retention aperture  13  for securing the carriage  12  to a reciprocating slide assembly. Inner and outer datum rail fasteners  17  and  19  (also shown in  FIG. 3 ) are shown to secure the inner datum rail  40  and the outer datum rail  42 , respectively, in place upon the carriage  12 . 
         [0043]    The components of the locating assembly  30  are shown in greater detail with reference to  FIG. 7 , viewed in a longitudinal direction.  FIG. 7  shows the rack insert  16  disposed upon the carriage  12 . However, in this view, it can be seen that the carriage  12  includes inner datum rail  40  and outer datum rail  42  upon which the rack insert  16  is positioned, which serve as locating and/or alignment rails in both load and work positions of the assembly  10 . The rack insert  16  includes a male rack alignment protrusion  44  that fits between the inner and outer datum rails  40  and  42 , such that the longitudinal orientation of the rack insert  16  is determined by a close fit between the rack alignment protrusion  44  and the interior surfaces of the inner and outer datum rails  40  and  42 . The lock pin  32  and lock shaft  34  are shown to engage a compression spring  46  which forces the lock pin  32  and lock shaft  34  among two counter-clockwise positions between an unclamped, but compressed, condition, and a clamped, partially-relaxed but engaged condition, which in turn correspond to the load position, work position (unclamped) and work position (clamped) of the assembly  10  respectively, as previously described. 
         [0044]    The various operating positions of the locating assembly  30  are shown in greater detail with reference to  FIGS. 9A-9D , viewed in an enlarged upper cross-sectional view.  FIG. 9A  is a composite view of the locating assembly illustrating its function among the multiple positions of the lock pin  32  during operation of this assembly. Operation of the locating assembly  30  is accomplished through the insertion of an Allen wrench (not shown) into the Allen wrench recess  31  of the lock shaft  34 , and subsequent rotation of the lock shaft  34 .  FIG. 9C  shows the locating assembly  30  in a loading position, with the lock pin  32  in a first position corresponding to that condition.  FIG. 9D  shows the locating assembly in an unclamped working position, resulting from rotation of the lock shaft  34  in a counter-clockwise manner, which moves the lock pin to the position designated as  32 ″. Release of the lock shaft  34  from the position shown in  FIG. 9D  then allows the lock pin to move to the position designated at  32 ′ in  FIG. 9B , which shows the locating assembly  30  in a clamped working position. The locating assembly  30  is also shown to have a taper of five degrees formed as a tapered recess side  39  of the second locating assembly recess  38  in the rack insert  16  through which the lock pin  32  is disposed. In the operation of the locating assembly  30 , the lock pin  32  is forced against this taper in the clamped working position and maintains bearing of the locating key  22  against the primary stop surface  33 , which helps to retain the lock pin  32  in the desired positions. Alternatively, it will be appreciated that other suitable tapers besides five degrees could also be used. 
         [0045]    Referring again to  FIGS. 1-4 , the spline rolling rack assembly  10  further includes a plurality of clamping assemblies, generally shown at  48 ,  50 ,  52  and  54 . Four clamping assemblies are shown in this example, although it will be appreciated that any suitable number of such clamping assemblies may be used depending on the configuration, dimensions and load requirements of the assembly  10 . The clamping assemblies  48 ,  50 ,  52  and  54  are disposed at spaced apart locations longitudinally within the carriage  12 , and operate to releasably secure the rack insert  16  in a pressurized manner in a fixed work position upon the carriage  12 , once the rack insert  16  has been moved from the load position to the work position. Each clamping assembly is operable for being adjusted between a released unclamped condition and an engaged clamped condition. The clamping assemblies operate by cam mechanisms which secure the rack insert  16  relative to the carriage  12  by a pressure action, which is believed to be more quickly and conveniently operated than the use of numerous individual bolts for securing these components together. 
         [0046]    The components and functions of the clamping assemblies will be discussed in greater detail with reference to  FIGS. 5, 6 and 10 , which show alternate embodiments of clamping assembly configurations, generally referenced with the numerals  48  and  48 ′. As with the locating assembly  30 , the clamping assemblies  48  and  48 ′ are each constructed as part of the carriage  12 , but also each engage a clamping assembly recess  56  within the rack insert  16 . As shown in  FIG. 5 , the clamping assembly  48  includes a cam  58  disposed within the carriage  12  that is accessible from the exterior of the carriage  12  through Allen wrench recess  63 , and engages a clamp pin  60 . The clamping assembly  48  also includes a keyhole insert  62  disposed against the rack insert  16  defining a passage for the clamp pin  60  to travel through for engaging the clamping assembly recess  56 , as well as a stop for release of the clamp pin  60 . Accordingly, the lock pin  60  is held in the assembly by virtue of its interface with the cam  58 . The clamping assembly recess  56  also includes a snap ring  64  for retaining the keyhole insert  62  in place and an anti-rotation pin  65  for providing proper orientation for the keyhole insert  62 . Disc springs  66  are also provided at an end portion of the clamp pin  60  for providing a suitable clamping force when the cam  58  is released, which are retained upon the clamp pin  60  by a snap ring  67 . 
         [0047]    The cam  58  and clamp pin  60  are shown in a clamped work condition in  FIG. 5 , and in an unclamped condition in  FIG. 6 . In the operation of this portion of the assembly, rotation of the cam from the configuration  58 ′ shown in  FIG. 6  into the configuration  58  shown in  FIG. 5  forces the clamp pin  60  downwardly toward the clamping assembly recess  56  of the rack insert  16 , thus placing the rack insert  16  and the carriage  12  in an engaged clamped condition. Similarly, rotation of the cam from the configuration  58  shown in  FIG. 5  into the configuration  58 ′ shown in  FIG. 6  forces the clamp pin  60  upwardly away from the clamping assembly recess  56  of the rack insert  16 , thus placing the rack insert  16  and the carriage  12  in a released unclamped condition. When this activity is performed for multiple clamping assemblies disposed longitudinally along the assembly  10 , the rack insert  16  and the carriage  12  can be clamped in the work position and unclamped, as desired. In each case, the clamping force on the rack insert  16  is spring pressure, as actuating the clamp pin  60  as described above compresses and decompresses the springs in order to unclamp and clamp the rack insert  16 , respectively. 
         [0048]      FIG. 10  shows an alternate construction for the clamping assembly, generally referred to at  48 ′. Unlike the embodiment shown in  FIGS. 5 and 6 , this embodiment does not use a keyhole insert  62  or snap ring  64 . Instead, in this embodiment, the clamping assembly recess  56  is machined directly into the rack insert  16 . In similar manner as for the previous embodiment shown in  FIGS. 5 and 6 , the clamping assembly  48 ′ also includes a cam  58  disposed within the carriage  12  that is accessible from the exterior of the carriage  12  through Allen wrench recess  63 , for engaging a clamp pin  60 . In this embodiment, the clamping assembly recess  56  itself defines a passage for the clamp pin  60  to travel, as well as a stop for release of the clamp pin  60 . Again, rotation of the cam  58  forces the clamp pin  60  downwardly toward the clamping assembly recess  56  of the rack insert  16 , thus placing the rack insert  16  and the carriage  12  in an engaged clamped condition. Similarly, rotation of the cam  58  back to its previous position forces the clamp pin  60  upwardly away from the clamping assembly recess  56  of the rack insert  16 , releasing the clamp pin  60  from its pressurized contact with the recess  56  of the rack insert  16  and placing the rack insert  16  and the carriage  12  in a released unclamped condition. 
         [0049]      FIG. 11  shows an enlarged front cross-sectional view of the alternate associated clamping assembly in a secured working position. From this view, and in combination with  FIG. 12 , it can be seen that the clamping assembly recess  56  has a small radius recess  57  and a large radius recess  59 , each formed as part of the clamping assembly recess  56 . The large radius recess  59  allows the clamp pin  60  to enter the clamping assembly recess  56  and corresponds to the load position. When the rack insert  16  is moved to the work position, the underside of the clamp pin  60  engages the small radius recess  57  by virtue of the applied pressure from disc springs  66  once the cam  58  is released. 
         [0050]    As shown in the longitudinal views of  FIGS. 5, 6, 7 and 10 , the primary contacting surfaces of the rack insert  16  against the inner and outer datum rails  40  and  42  of the carriage  12  are designated as the inner height location datum  68  and outer height location datum  70 . The inner height location datum  68  and outer height location datum  70  serve the function of being the surfaces that are manufactured to the closest tolerances (and typically formed last in the manufacturing process of the rack insert  16 ) so that the feature-forming surfaces (such as teeth  20 ) of the rack insert  16  can in turn be brought to the closest configuration and dimension tolerances. It is believed that using the inner height location datum  68  and outer height location datum  70  in this way provides improved tolerances in a more efficient manner of manufacturing the rack insert  16 , as opposed to the previous method of manufacturing the required tolerances (such as by grinding) into the feature-forming surfaces (such as teeth  20 ) as the final manufacturing step of the rack insert  16 . 
         [0051]    In the method of the present disclosure, the rack insert  16  is positioned upon the mounting surface  14  of the carriage  12  in such a manner that the load arrows  35  and  37  are aligned, as shown in  FIG. 1 . In this condition, the locating key  22  (which is secured upon the carriage  12  by the locating bolt  28 ) engages the first locating key recess  24  disposed within the rack insert  16 . At the same time, the clamp pin  60  engages the large radius recess  59  of the clamping assembly recess  56  in the rack insert  16 , as shown in  FIG. 12 . The locating assembly  30  is then actuated by the engagement of Allen wrench recess  31  with a suitable Allen wrench, so that the lock shaft  34  is rotated counter-clockwise, moving the rack insert  16  longitudinally relative to the carriage  12  into the working position (but unclamped) shown in  FIG. 2 . In this activity, the load arrows become displaced relative to each other, as shown at reference numerals  35 ′ and  37 ′ in  FIG. 2 , and the lock pin moves from the loading position shown at numeral  32  in  FIG. 9C  to the position shown at numeral  32 ″ in  FIG. 9D , which represents the unclamped working position of the assembly. Release of the lock shaft  34  then allows it to travel toward the front of the assembly under spring pressure exerted by spring  46 , shown in  FIGS. 3 and 7 , which permits the lock pin to bear against the tapered recess side  39  in the rack insert  16  in the position designated with the numeral  32 ′ in  FIG. 9 b   , which represents the clamped working position of the assembly. At the same time, this activity forces the locating key  22  to bear upon the primary stop surface  33 , as shown in  FIGS. 1, 2, 13 and 14 . 
         [0052]    Securing the assembly in the clamped working position also requires the release of cam  58  in each clamping assembly  48 ,  50 ,  52  and  54  by engaging the Allen wrench recess  63  with a suitable Allen wrench and rotating the cam  58  in either a clockwise or counter-clockwise direction within the lock pin recess  61  such as to the position marked as  58  in the embodiment shown in  FIG. 5  (and performed similarly in the embodiment illustrated in  FIG. 10 ). This in turn causes the clamp pin  60  to travel in a manner away from the rack insert  16 , which partially relaxes the disc springs  66  and allows the clamp pin  60  to bear on the clamping assembly recess  56 . 
         [0053]    Removal of the rack insert  16  from upon the carriage  12  involves releasing each clamping assembly  48 ,  50 ,  52  and  54  from the clamped to the unclamped condition while the overall assembly is in the working position. To accomplish this (for each clamping assembly), the Allen wrench recess  63  is engaged with a suitable Allen wrench and rotated clockwise or counter-clockwise within the lock pin recess  61 , which causes the clamp pin  60  to travel toward the rack insert  16 , releasing the clamp pin  60  from bearing upon the clamping assembly recess  56  and unclamping the assembly. The assembly is then moved from the working position to the loading position by actuating the locating assembly  30  by the engagement of Allen wrench recess  31  with a suitable Allen wrench, so that the lock shaft  34  may be depressed and then rotated clockwise, moving the rack insert  16  longitudinally relative to the carriage  12  into the loading position shown in  FIG. 1 , with the load arrows moving from the unaligned positions shown at  35 ′ and  37 ′ in  FIG. 2  to the aligned positions shown at  35  and  37  in  FIG. 1 . Once in the loading position, the rack insert  16  may be removed from upon the mounting surface  14  of the carriage  12 . 
         [0054]    Since typical spline rolling racks include upper and lower spline rolling rack assemblies such as the assembly described herein, it will be appreciated that the above description of both apparatus and method typically apply to both an upper and lower assembly, which must both be installed and secured before operation of the overall spline rolling rack machine can begin. 
         [0055]    The foregoing description of the embodiments has been provided for purposes of illustration and description. It is not intended to be exhaustive or to limit the disclosure. Individual elements or features of a particular embodiment are generally not limited to that particular embodiment, but, where applicable, are interchangeable and can be used in a selected embodiment, even if not specifically shown or described. The same may also be varied in many ways. Such variations are not to be regarded as a departure from the disclosure, and all such modifications are intended to be included within the scope of the disclosure.