Abstract:
A powered driver and methods are disclosed, the driver including a head having a gapped jaw and housing a motor driven drive transfer assembly for operating a rotatable split socket engageable at a threaded connector. A reaction unit is movably maintained through the head, and a probe is associated with the reaction unit. The methods of this invention include setting a selected rotational limitation at the driver relating to fitting characteristics, operating the driver to cause relative rotation of a connector nut located in the socket and connector body engaged by the reaction unit. One of a plurality of operational modes for driver operations is selected and relative movement of the head and reaction unit are monitored during driver operation. The driver is controlled so that driver operation ceases when a selected combination of events related to operational mode selected and at least one of rotational limitation setting, monitored relative movement or driver operation occurs.

Description:
RELATED APPLICATION 
       [0001]    This application is a Continuation-In-Part Application of U.S. patent application Ser. No. 12/004,757 filed Dec. 21, 2007 and entitled “Drive Engagement, Safety and Control Apparatus For A Powered Connector Driver”, which application is a Continuation of U.S. patent application Ser. No. 11/634,695 filed on Dec. 6, 2006 entitled “Powered Driver With Location Specific Switching” (now issued as U.S. Pat. No. 7,311,025). 
     
    
     FIELD OF THE INVENTION 
       [0002]    This invention relates to drivers for tools, and, more particularly, relates to powered nut drivers. 
       BACKGROUND OF THE INVENTION 
       [0003]    Powered drivers, both pneumatic and electrical, for manipulation of various types of tools (such as sockets for threaded connectors) are well known. In many applications, such as manipulation of threaded line fittings (i.e., unions or the like) found in all gas or liquid processing or delivery operations and assemblies, correct tightness of the fitting is critical to assure a sound connection and to avoid leakage (which may occur if line fittings are either over or under tightened). 
         [0004]    Numerous approaches to gauging the correct tightness of such connectors have been heretofore suggested and/or utilized, with varying degrees of success. Torque requirements for driving large and small fasteners vary such that the same driver often cannot be employed for different fasteners. Moreover, devices and methods for gauging fitting integrity during fitting installation that are used for pneumatic tools are frequently not applicable for electrical drivers and vice versa. Such heretofore known approaches are often not highly accurate and repeatable, and/or are quite expensive computer-based applications of limited utility in the field. 
         [0005]    In certain high torque application, reaction torque can be so high that driver components seize. Mechanical driver switching, moreover, has been subject to compromise due to conditions of use (particularly related to moisture or chemical contamination). Finally, heretofore known tools have often relied on a single control technique to assure correct fitting tightness, eschewing backup means. Reliance on the driver&#39;s operator for correct fastener securement often leads to fastener failures related to operator error. 
         [0006]    A fitting of a specific type (manufacture and/or fitting characteristics and materials) and size has remarkably similar tolerances (range of correct fitting tightness) one fitting to the next and can be manipulated similarly during securement. Tolerances for fittings of different types and sizes, likewise, should be treated differently during field application. Heretofore known drivers have not always made use of such readily quantifiable distinctions. Further improvement of such drivers and driving methods could thus still be utilized. 
       SUMMARY OF THE INVENTION 
       [0007]    This invention relates to improved drivers and methods for manipulating threaded connectors that accommodate reliable repeated precise tightening of threaded connectors based on location specific switching. In particular, methods for reliable repeated securement of threaded connectors that include a nut and a body to a correct tightness utilizing a powered driver that includes a nut engaging head and an associated connector body engaging unit, the head and engaging unit movable relative to one another, are disclosed. The methods include the steps of setting a selected rotational limitation at the driver relating to fitting characteristics, engaging the nut and the body of the connector at the head and engaging unit, respectively, and then operating the driver to cause relative rotation of the nut and the body. The driver is caused to cease operating when an event related to either one of rotational limitation setting and driver operation occurs. 
         [0008]    Related methods are provided for reliable repeatable gauging of correct tightness of threaded fittings utilizing a powered driver that includes a gear tooth surface associated with a socket for nut rotation and movement toward the fitting body during driver operation. These methods include steps for maintaining a count of teeth of the gear tooth surface passing a location at the driver during a selected interval of operation of the driver and gauging relative location of the socket and fitting body during movement toward the fitting body. The maintained count(s) and the gauging are selectively utilized to control driver operation. 
         [0009]    The threaded fitting drivers of this invention include a driver head having a rotatable socket thereat for engaging the fitting. Means for rotating the socket are associated with the driver head, a reaction unit movable at the driver head relative to the socket and engageble with the fitting. A controller accepts user input of at least either a selected operational mode from a plurality of modes including pulse mode and swage mode or a selected socket rotational limitation, and initiates precision cessation of socket rotation in accord with the user input. 
         [0010]    It is therefore an object of this invention to provide drivers and methods for manipulating threaded connectors that accommodate reliable repeated precise tightening of threaded connectors based on location specific switching techniques. 
         [0011]    It is another object of this invention to provide drivers and methods for manipulating threaded connectors that recognize and react to driver malfunction and/or fitting defect. 
         [0012]    It is still another object of this invention to provide drivers and methods for manipulating threaded connectors that utilizes non-contact driver control switching. 
         [0013]    It is yet another object of this invention to provide powered fitting drivers and methods utilizing gauging to accommodate specific fitting tolerances. 
         [0014]    It is still another object of this invention to provide drivers and methods for manipulating threaded connectors that includes backup driver control techniques to assure correct fitting tightness. 
         [0015]    It is another object of this invention to provide drivers and methods for manipulating threaded connectors that reduces the likelihood of, and/or recognizes, operator error. 
         [0016]    It is still another object of this invention to provide a method for reliable repeated securement of threaded connectors that include a nut and a body to a correct tightness utilizing a powered driver that includes a nut engaging head and an associated connector body engaging unit, the head and engaging unit movable relative to one another, the method including the steps of setting a selected rotational limitation at the driver relating to fitting characteristics, engaging the nut and the body of the connector at the head and engaging unit, respectively, operating the driver to cause relative rotation of the nut and the body, and causing the driver to cease operating when an event related to either one of rotational limitation setting and driver operation occurs. 
         [0017]    It is yet another object of this invention to provide a driver for reliable repeated securement of threaded fittings to a correct tightness that includes a driver head, a rotatable socket at the driver head for engaging the fitting, means for rotating the socket associated with the driver head, a reaction unit at the driver head movable relative to the socket and engageble with the fitting, and control means for user input of at least one of a selected socket rotational limitation and a selected operational mode from a plurality of modes including pulse mode and swage mode, and for precision cessation of socket rotation in accord with the user input. 
         [0018]    It is yet another object of this invention to provide a method for reliable repeatable gauging of correct tightness of threaded fittings that include a nut and a body secured utilizing a powered driver that includes a gear tooth surface associated with a nut engageable socket for nut rotation and movement toward the fitting body during driver operation, the method steps including maintaining a count of teeth of the gear tooth surface passing a location at the driver during a selected interval of operation of the driver, gauging relative location of the socket and fitting body during movement toward the fitting body, and selectively utilizing the maintained count(s) and the gauging to control driver operation. 
         [0019]    With these and other objects in view, which will become apparent to one skilled in the art as the description proceeds, this invention resides in the novel construction, combination and arrangement of parts and methods substantially as hereinafter described, and more particularly defined by the appended claims, it being understood that changes in the precise embodiment of the herein disclosed invention are meant to be included as come within the scope of the claims. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0020]    The accompanying drawings illustrate a complete embodiment of the invention according to the best mode so far devised for the practical application of the principles thereof, and in which: 
           [0021]      FIG. 1  is a perspective view showing the tool driver of this invention; 
           [0022]      FIG. 2  is a reverse perspective view of the driver of  FIG. 1 ; 
           [0023]      FIG. 3  is a partial exploded view of the housing and components of the driver of this invention; 
           [0024]      FIG. 4  a detailed exploded view of housed drive train elements not shown in  FIG. 3 ; 
           [0025]      FIG. 5  is a partial exploded view of the driver head of the driver of this invention; 
           [0026]      FIG. 6  is a second partial exploded view of the head of the driver of this invention; 
           [0027]      FIG. 7  an elevation view of the head of the driver of this invention with the top cover removed; 
           [0028]      FIG. 8  is a sectional view taken along section lines  8 - 8  of  FIG. 3 ; 
           [0029]      FIG. 9  is a sectional view taken along section lines  9 - 9  of  FIG. 7 ; 
           [0030]      FIG. 10  is a sectional view taken along section lines  10 - 10  of  FIG. 7  but with the top cover and reaction unit in place; 
           [0031]      FIG. 11  is a partially exploded perspective view showing additional features which may accompany the driver of this invention; 
           [0032]      FIG. 12  is a perspective view illustrating still other additional features which may accompany the driver of this invention; 
           [0033]      FIGS. 13 through 15  are schematic diagrams showing the electronics of the driver of this invention; 
           [0034]      FIG. 16  is a perspective view of showing a second, and now preferred, embodiment of the driver of this invention; 
           [0035]      FIG. 17  is another perspective view of the driver shown in  FIG. 16 ; 
           [0036]      FIG. 18  is an exploded view of the driver shown in  FIG. 16 ; 
           [0037]      FIG. 19  is a partial side view illustrating user operational controls and indicators of the driver shown in  FIG. 16 ; 
           [0038]      FIG. 20  is a perspective view of the operations sensor array of the driver shown in  FIG. 16 ; 
           [0039]      FIGS. 21 and 22  are partial sectional views taken along section lines A-A of  FIG. 17 ; 
           [0040]      FIG. 23A  is a partial sectional view taken along section lines B-B of  FIG. 16 . 
           [0041]      FIG. 23B  is a sectional view taken along section lines C-C of  FIG. 16 ; 
           [0042]      FIG. 24  is a partial perspective view of another alternative operations gauging implementation usable with the driver of this invention; 
           [0043]      FIG. 25  is a is an exploded view of the implementations of  FIG. 24 ; 
           [0044]      FIG. 26 through 29  are schematic diagrams showing now preferred electronics of the driver of this invention and including adaptations accommodating features of the driver shown in  FIG. 16 ; and 
           [0045]      FIGS. 30 through 35  are flow diagrams illustrating programmed control of the driver of this invention including the features and adaptations shown in  FIGS. 16 and 26  through  29 . 
       
    
    
     DESCRIPTION OF THE INVENTION 
       [0046]    Powered driver  21 , for rotating tools such as sockets or the like to manipulate threaded connectors, is illustrated in  FIGS. 1 through 3 . Driver  21  includes driver head  23 , motor module  25  (any means of applying motive force could be used including electrical, pneumatic or fluid drive motors), electronics module  26 , reaction unit  27 , housing  29 , and battery pack  30 . Torque amplification drive train modules  32  and  33  provide a drive train capable of staged increase of torque from a motor  25  rating of about 0.18 ft.lbs. to over 35 ft.lbs., thereby accommodating connector manipulation in a wide variety of size and torque application categories (torque amplification is adaptable to requirements). Housing  29  is hollow at both barrel portion  35  and handle portion  37  thus providing the required space and protection for driver electrical components as hereinafter discussed. Battery pack  30  is of standard configuration and includes a standard conductive slide connector  39  (with mating unit  41  at handle portion  35 ) providing both connectivity and security of batteries in pack  30 . 
         [0047]    As shown in  FIGS. 3 and 4 , torque amplification modules  32  and  33  include discrete gear sets in separate housings to accommodate different torque output requirements in different tool configurations. The final output stage  33  includes primary drive output shaft and bevel gear  45  receivable through opening  47  at head  23  (see  FIG. 5 ). 
         [0048]    Operational switches, lights and ports are readily accessible, including main on/off switch  51 , main operational running switch/trigger  53 , forward and reverse jog rocker switch  55  (for advancing or retreating rotation by one to five degree increments), and lights switch  57  (operating white light  59  and red, night light  61 ). USB port  63  provides communication and data download capabilities (from onboard controller memory) as discussed hereinafter. Control lights  65 ,  67 ,  69  and  71  are provided to indicate tool on/off status (yellow— 65 ) and socket status ( 67 —green indicating socket  73  centering at jaw opening  75  and safety switch  77  tripped by placement of a line and fitting  79  (see  FIG. 2 )). Light  69  blinks (red) at each full rotation of socket  73 , and thus a fitting engaged thereat, and light  71  indicates (blue) when the correct connector tightness (nut to fitting body gap, for example) has been achieved. 
         [0049]    Housing  29  is preferably a split housing (as shown) held by common fastener techniques, with the housing, when assembled, capturing head  23  at mounting bracket  80 . Modules  25 ,  26 ,  32  and  33  are affixed to one another and to head  23  utilizing standard screw type fasteners  82 . 
         [0050]    Turning now to  FIGS. 5 through 10 , head  23  and reaction unit  27  will be described in greater detail. Head  23  includes main body  83  and top cover  85  held together using screws  87 . Gapped jaw  75  is utilized in this embodiment of the driver to accommodate use of a split socket tool  73  (a hex socket, for example) used to manipulate line fittings ( 79 , as shown in  FIG. 2 ). Drive translate assembly  89  includes stacked gears  91  and  93  on shaft  95  and bearing set  97  pressed into main body mounting  99 , bevel gear  93  engaged by primary drive output gear  45  of final output stage  33  of torque amplification modules  32  and  33 . The opposite end  101  of shaft  95  is rotatably fitted into mount  103  in cover  85 . 
         [0051]    Drive transfer gear assembly  107 , including main drive gear  109  and idler gears  111  and  113 , complete the drive train. Main drive gear  109  engages gear  91  of translate assembly  89  and is mounted on shaft  115  of main body  83 . Idler gears  111 / 113  are used in split socket applications, providing constant drive application to socket  73  at their outer gear tooth surfaces, and are mounted on bearing shoulders  117  in housing detents  119  and cover openings  121 . Socket  73  is mounted on bearing shoulder  123  in housing detent  125  and cover opening  127 . Main drive gear  109  and socket  73  preferably are the same size and have the same gear tooth count at their outer gear tooth surfaces, so that rotation thereof is one to one. Cam surface  131  is provided at gear  109  and follower  133 , the roller of roller switch  135 , is mounted at main body  83  adjacent thereto using screws  137 . This arrangement provides indication of socket  73  rotation at light  69  as well as socket location (in degrees) and rotation counting in onboard controller software or firmware. 
         [0052]    Reaction unit  27  includes fitting engagement  141  (gapped for receipt of line fittings as shown in this embodiment) for engaging a utility related to the body of the connector being manipulated (for example, a line fitting body, the second part of a line fitting assembly not including the nut). Engagement  141  in this embodiment, for example, includes a sized slot  143  having surfaces configured to receive and securely hold a hexagonal fitting body. Rail guides  145  and  147  (a single guide could be utilized in some embodiments of the driver of this invention) are received at reduced diameter threaded ends  149  through openings  151  of engagement  141  and are held thereat by cap nuts  153 . 
         [0053]    Guide  145  includes second reduced diameter end  155  engageable (pressed into) opening  157  of piston  159 . Guide  145  also includes intermediate annular slot  161  for capture and retention of reaction unit  27  by clip  163  at cover  85  (during fitting loading, reaction unit  27  must be held in an opened, disengaged position, since, as will be appreciated, the entire unit  27  is spring biased). Guides  145  and  147  are receivable through openings  121  in cover  85 , through openings  164  of idler gears  111  and  113 , and the openings into body  83  through threaded shoulders  165 . 
         [0054]    Clip  163  is mounted at the end of spring biased latch body  166  held in latch mount  167  attached to cover  85 . Spring  169  is held in mount  167  between body  166  and mount  167  and biases body  166  so that clip  163  is urged toward and across one opening  121  of cover  85  and into engagement with rail guide  145 . Release grip  171  protrudes from body  166  allowing user access for movement of latch body  166 . Sliding movement of reaction unit  27  on guides  145  and  147  (against unit bias as discussed hereinafter) away from head  23  eventually results in movement of clip  163  into engagement at annular slot  161  thus allowing cocked retention of reaction unit  27  at this position. Once a fitting is correctly positioned at the driver, retraction of latch body  166  using release grip  171  by a user frees clip  163  from slot  161  allowing movement of unit  27  toward head  23  and into correspondence with a connector utility at engagement  141 . 
         [0055]    Probe component  175  of switching assembly  177  is threadably received through opening  179  of engagement  141 , probe reach being adjustable by extent of threaded engagement. Probe end  181  is receivable through openings  183  and  185  in cover  85  and body  83 , respectively. Switch component  187  of assembly  177  (a roller switch, for example) is attached by screws  189  to a mounting block  191  (as shown in  FIG. 11 ) on body  83  to position the roller of roller switch  187  over opening  185  and thus in the path of probe end  181 . Switch component  187  is operatively linked (through controls as shown hereinafter) with the main motor of the driver to decouple motive force when tripped by probe end  181 . 
         [0056]    Engagement  141  of reaction unit  27  is biased toward driver head  23  (and particularly toward socket  73 ) by springs  195  in closed ended retainers  197  and  199  threadably engaged at shoulders  165 . Springs  195  are maintained between shoulders  165  and piston  159  at retainer  197  and slide  201  at retainer  199  thus biasing the piston and the slide (and so guides  145  and  147  and the rest of reaction unit  27 ) toward the closed ends of the retainers  197  and  199 . Slide  201  is retained at the end of guide  147  by manually releasable spring clip  203  received through slide slot  205 , threaded opening  207  in slide  201  and annular slot  209  at guide  147 . When spring clip  203  is retracted from slot  209  thus releasing guide  147 , reaction unit  27  may be fully withdrawn from head  23 . 
         [0057]    As may be appreciated, as a fitting nut is tightened on a fitting body using the driver of this invention, engagement  141  of reaction unit  27  in contact with the fitting body is biased toward socket  73  at the same rate as the nut moves toward the fitting body. At the same time, probe end  181  is proceeding at this rate toward switch component  187 . By virtue of probe length and/or geometry selection (either factory selected for particular operations, threadably adjustable, or by selection and installation of one of a variety of probe components having different selected lengths for different fitting specifications), switch contact occurs when correct connector or fitting (nut to body gap) tightness is achieved thereby causing cessation of socket rotation. Such operations are highly predictable and thus repeatable. Since most motor and drive trains have overrun (i.e., a few degrees of continued rotation due to system momentum), the driver is programmed with an automatic reverse rotation at the end of the tightening cycle corresponding to estimated system overrun to relieve system tension without changing nut torque. Use of the jogging function can provide further tightening or loosening as desired. After disengagement from a tightened fitting, split socket  73  is run to the gap centered position relative to jaw opening  75  (for example, in a fully automated mode, by a subsequent press of trigger switch  53  after release thereby running socket  73  to the centered position—indicated by light  67 —and resetting the driver for a new connector driving cycle). 
         [0058]    Reaction unit  27  may be manually reset for a new cycle (“cocked” as described above) or may be reset by pneumatic means as shown herein. Pneumatic fitting  211  is threaded at opening  213  of retainer  197  and connected by line  215  with valve  217  and pressurized gas cylinder  219 . After a fitting is tightened, triggering valve  217  causes a burst of gas to enter retainer  197  through opening  213  forcing piston  159  against spring bias to move guide  149  (and thus unit  27 , releasing and resetting switch component  187 ) until slot  161  captures spring biased retaining clip  163 . 
         [0059]    Turning to  FIGS. 11 and 12 , several additional driver features may be provided to enhance safety and utility. Safety switch assembly  225  includes switch  77  pivotably biased to a position closing gapped jaw  75 . When forced open by a line or other fitting  79 , switch  77  geometry causes engagement at roller switch  227  attached to head  23  thereby electrically enabling driver operation. A second pneumatic fitting  229  is positioned for access to the interior of retainer  197 . Line  231  connected with fitting  229  is received at port  233  of a test fixture  235  to thereby receive continuously aspirated samples from the fitting\connector union area through retainer  197  and bore hole  236  through guide  145  (see  FIG. 5 ). Leak detection at a fitting may thus be accommodated. 
         [0060]    Test fixture  235  may be belt mounted, as shown, and may include a USB input  239  (for communication through the USB port at the driver or with a base computer). BLUE TOOTH and/or radio communication may be provided for data download from the driver or upload from a base station. Cellular technology may also be accommodated for the user, with a speaker  241  and microphone  243  positioned at housing  29  or any of the driver modules. Real time video may be provided at video unit  245  (and downloaded or stored with appropriate in-situ memory), allowing remote review of operations and/or a record of completed tasks. 
         [0061]      FIGS. 13 through 15  illustrate the electronic implementation of driver  21  of this invention, the boards described hereinafter housed in module  26 . Main control board  247  ( FIG. 13 ) is connected with switching board  249  ( FIG. 14 ) at port connectors  251 . Board  249  is connected with the two one-half h-bridge circuits  253  and  255  at connectors  257  and  259  ( FIG. 15 ), the h-bridge circuits driving motor  261  (housed at module  25 ) in a conventional arrangement. Main board  247  includes a smart highside current power switch arrangement  263  (for example, a PROFET BTS660P by INFINEON TECHNOLOGIES) and a Flash USB ready microcontroller  265  (for example, a PIC18F2455/2550/4455/4550 series 28/40/44 pin microprocessor by MICROCHIP TECHNOLOGY, INC.) connected with clock oscillator  266 . USB signals are accommodated at the connector to USB port  63 . 
         [0062]    Programming/reset circuits  267  are provided for programming and troubleshooting with programming switch  269  (modes may include everything from fully manual to fully automated), and voltage regulation is provided by regulator circuit  270 . Momentary rocker switch  55  with center off provides for input to controller  265  of jog functions, and trigger switch  53  inputs running commands. Safety gate switch  227  inputs run ready signals, and rotation counter switch  135  inputs socket rotation count/location data. 
         [0063]    Connectors  281  and  283  at switching board  249  are connected with lights  61  and  59 , respectively, for operations responsive to switch  57  actuation. Switch  285  is a mode selection switch (manual or auto). On/off switch  51  signals are input through board, and motor control signals are output through, board  249 . H-bridge circuits  253  and  255  include integrated motor drivers  287  and  289 , respectively (for example, VNH2SP30-E drivers from ST). 
         [0064]    Second embodiment  301  of the driver of this invention including various now-preferred fitting integrity gauging techniques and apparatus is shown in  FIGS. 16 through 23 . Unchanged elements of the driver will be numbered in the drawings as heretofore identified (or will remain unidentified if not pertinent to the changes in embodiment  301 ). Driver embodiment  301  includes a combined torque amplification module  303  adapted to replace the separate modules heretofore shown but functioning in a similar manner (and having output at a bevel gear of the type shown heretofore at  45 ). User manipulable control array  305  is located at barrel  35  and includes switching associated with controller  265 . The switching includes main on/off switch  57 , three way operational mode selection switch  307  and two way nut/socket rotation limitation selection switch  309  (see  FIG. 19 ). 
         [0065]    As shown in  FIGS. 17 ,  21  and  22 , manual reset arm assembly  311  is provided for cocking reaction unit  27  for a new operational cycle. Assembly  311  includes retainer  313 , reset arm  315  operable across pivot  317  to manipulate integrated ram  319  abutting rail guide  145 . Non-contact sensor array  321  (preferably an array of hall effects sensors) is contained by main array cover  323  secured to main body  83  of head  23  and covering opening  325  (see  FIG. 23B ) therethrough. Sensor array  321  is mounted on board  327  secured in turn at recess  329  of cover  323  using conventional means (see  FIGS. 18 and 20 ). The array includes output port connector  331  for communicating the output from Hall effects sensors  333 ,  335  and  337  to the main driver circuitry. Cover  323  is preferably clear or opaque to allow visual inspection of integrated lights (see  FIG. 29 ) for user operational monitoring. 
         [0066]    Sensor  333  includes an integrated magnet molded on the back of the sensor that creates a field around the sensor. Sensor  333  is positioned in pocket  334  in head  23  (the head is preferably made of aluminum) so that the sensor and field are concentrated on and in proximity to the teeth of drive gear  109  (see  FIG. 23A ). Disturbances in the magnetic field are caused by passage of the individual teeth and valleys between teeth during rotation of gear  109 , and these disturbances are sensed and by sensor  333 . The sensed disturbances are counted, thus essentially providing a count of gear  109  teeth passing the sensor during a given period, thereby to communicate monitored angular location data equivalent to observed rotation of gear  109  to controller  265 . This data may be utilized as noted heretofore (replacing cam and switch  131 / 133 / 135 ). Since the number of teeth on the gear is known, with Hall effects sensor  333  operating in a conventional manner angular rotation of socket  73  (having the same number of teeth) can be calculated. While sensing of this data is shown at the drive gear, the same data could be gathered by placement of the sensor adjacent to any of the other gear tooth surfaces utilized in the driver, though in some cases conversion calculations would be required. 
         [0067]    Sensor  335  is responsive to magnet  339  mounted on drive gear  109  (see  FIG. 23B ) in head  23  to communicate monitored precise location of the gap in socket  73  to index the gap with the equivalent gap in jaw  75  for application and removal of the tool from a fitting. This is accomplished by causing cessation of gear rotation when sensor  335  senses optimum field strength/location of magnet  339 . This cessation location (with magnet  339  in closest proximity to sensor  335 ) is precisely indexed with the exact coincidence of the gaps in split socket tool  73  and jaw  75  of head  23 . The monitored indexing data is communicated to controller  265 . 
         [0068]    Sensor  337  is located adjacent to passageway opening  185  through driver head body  83  and opening  343  of cover  323 . As shown in  FIGS. 18 ,  20 ,  21  and  22 , cover  323  houses and carries magnet  347  in magnet holder at one end thereof. Sensor  337  is responsive to the movement of the distal end of probe  345  of reaction unit  27  through the field of magnet  347  as it moves from a fitting unsecured location ( FIG. 21 ) and passes the sensor ( FIG. 22 ) to indicate proper tightness of a fitting being secured by driver  301  (thus replacing switch  187 / 177  functionally with a more durable switching unit less subject to corruption from moisture and chemical contamination and the like). Monitored data related to relative position of the driver head/socket/nut and reaction unit/probe/connector body is communicated to controller  265 . 
         [0069]    An alternative technique for gauging the relative position of the driver head/socket/nut and reaction unit/probe/connector body for indication of correct fastener tightness is shown in  FIGS. 24 and 25 . This embodiment replaces limit switch  187 / 177  with linear resistor unit  353  to regulate motor speed (to regulate nut to body gap closure speed at different stages of the traversed distance) as well as motor shut-off. Unit  353  includes housing  357  containing the resistor circuit, plunger  359 , and communication port for unit connection with the circuitry of controller  265 . The unit is mounted over retainers  197  and  199  using bridge  363  having unit retention pocket  365  thereat. Plunger  359  is received at guide  367  mounted over opening  185  of driver head body  83 . As shown heretofore, opening  185  receives probe tip  181  (see  FIG. 10 ) therethrough as probe  175  moves during fastener tightening. Probe movement also extends through central opening  369  of guide  367  and into contact with the plunger  359  of unit  353 . In this fashion, motor control is accommodated, and proper tightness of the fastener is repeatedly achieved. 
         [0070]    A second, and now preferred, electronic implementation of driver  21  of this invention is illustrated in  FIGS. 26-29  (particularly adapted for use with embodiment  301  of the driver, though also adaptable for use with the embodiment of driver  21  shown in  FIG. 1 ). Unchanged elements of the driver circuitry will be numbered in the drawings as heretofore identified (or will remain unidentified if not pertinent to the changes in this implementation). Main board  375  is connected directly with H-bridged circuit  255  at connector  377 . Unified using connector  379  is received therein from circuit  255 . Sensors connector  381  receives port connector  331  of sensor array  321 . EEProm  383  stores swage fitting data collected during swaging processes as discussed hereinafter, the data used to determine, for example, when a swage is good, when a ferrule is missing, or when a fitting is already in swaged condition. 
         [0071]    Temperature sensor  385  monitors main board temperature, and real time clock  387  is used to date/time stamp connector securement events (completed swages, for example). Sound module  389  is used to broadcast an alert to a user of error conditions encountered during operations. Switch board  391  includes the switches at array  305 , among others, and operational signal lights  393  and  395 . Lights  393  and  395  are bicolor LED&#39;s replacing lights  67  and  69  (at  393 ) and signal lights  65  and  71  (at  395 ). Sensor array board  321  includes sensors  333 ,  335  and  337 , and operator monitoring LED&#39;s  397 ,  398  and  399  operable when the related sensor is active. 
         [0072]    Turning now to  FIGS. 30 through 35 , program control techniques at controller  265  for use with the various embodiments of driver  21  (particularly embodiment  301 ) of this invention are illustrated. Once the driver is powered on (at switch  57 ), it may be used to power-off at any time. When restarting in such case, requires the safety switch to be held for a safe restart. Thereafter, various functions are initialized and the main loop is entered whereat the driver await operator input. Once awakened ( FIG. 31 ), the control searches for jog function input, user selected rotation limitation input and/or operational mode input. The jog function mode ( FIG. 35 ) is used for operator relocation of the socket and/or reverse rotation operations. The jog function includes a high power and lower power operational modes selectable by a user (in both forward and reverse rotation). The high power mode is used, for example, for nut tightening and nut release where greater power is required, and is essentially selected by a second trigger input after jog function mode operations are entered. The low power mode is used, for example, for fine nut/driver alignment or other low power operations. When the selected operations are completed, the main loop is again entered. 
         [0073]    Selection of rotation limitation ( FIG. 31 ) is directed to limiting rotation to 270° of nut/socket rotation (smaller fasteners— 3/16″ and smaller) or 540° of nut/socket rotation (larger fasteners—¼″ and larger). This selection in turn results in a pair of tooth count limit parameters being set (in each case), for example a tooth count threshold set point of 24 or 40 teeth (depending on limitation selected) and a tooth count limit of 29 or 45 teeth (again depending on rotation limitation selection). These counts could be more finely divided (and programmed in the field if necessary) for more precision selections availability and/or supplemented with look-up tables or the like related to particular fastener manufacturer, material, specification, tolerances and so forth to aid further precision. 
         [0074]    Mode selection currently includes three possible selections (though more or fewer could be provided). Selection of a particular mode enters individualized process loops related to the selected mode. In pulse mode only functions related to monitored relative movement of fastener nut and body (sensor  337 ) are completed, and only driver events related to the same trigger driver control functions (“made limit” referred to in  FIG. 32  refers to sensor  337 , switch  187 / 177  or linear resistor unit  353  signal correspondence with probe tip  181 ). Auxiliary mode is a reserved functionality related solely to user operation of the driver via the run and jog switches  53  and  55  (see  FIG. 34 ). 
         [0075]    In swage mode functions related to both rotation selection (tooth counts at sensor  333 ) and monitored relative movement of fastener nut and body are completed, and only driver events related to the same trigger driver control functions ( FIG. 33 ). The tooth count threshold set point parameter is utilized as a speed control mechanism to allow nut run-up. The tooth count limit is utilized along with the nut/body proximity sensed/monitored data to achieve correct fastener tightness and swage integrity and/or to note various failures or potential failures. Every swage operation and its related status is reported and saved, and various report codes are entered. 
         [0076]    Other control options to help assure proper fastener integrity could be utilized. For example, power consumption data during a tightening operation can be monitored and reported (for example, using motor  261  current draw) and plotted versus time interval and tooth count to seek the exact point between 400° and 540° that power draw ramps up to a peak and then falls off slightly (indicating the a tube fitting ferrule has begun to yield), thereafter ramping up and peaking again (indicating full ferrule compression). This correlation is used to cease driver operation at the first peak and fall off assuring proper fitting tightness. This same data can be utilized to spot missing ferrules or otherwise defective fittings, driver malfunction (binding or the like) and operator errors. 
         [0077]    As may be appreciated, this invention provides a highly adaptable power driver and driver control methods for precise manipulation of threaded connectors that employs various operational gauging and location specific switching to repeatably accomplish reliable and correct connector tightening thus better assuring fastener integrity.