Abstract:
The stabilizer apparatus for a power head attachment for rotationally powered tools in which a housing supports a stabilizer apparatus including a stabilizer collar rotatable to selected positions relative to the input shaft of the head attachment and a stabilizer arm pivotally mounted on the collar for movement to selected angular positions relative to the axis of the input shaft between a plurality of locked positions and a single unlocked position. In the unlocked position of the arm, the collar can be rotated to various circumferential positions and in each one of the positions the stabilizer arm can be located at a selected one of multiple angular positions which also lock the arm and collar in a fixed position making possible many combinations of positions of the stabilizer arm relative to the power head of the tool.

Description:
REFERENCE TO RELATED APPLICATION 
   This application claims priority of U.S. Provisional Patent Application Ser. No. 60/494,187, filed Aug. 11, 2003, the entire content of which is incorporated herein by reference. 

   FIELD OF THE INVENTION 
   This invention relates to drive attachments for rotary tools and more particularly to stabilizing arms or torque absorbing arms for such tools and attachments. 
   BACKGROUND OF THE INVENTION 
   Attachments to rotary tools such as cordless rotary drills or screwdrivers require careful positioning to maintain alignment between the work to be performed and the rotating output tool. Also, the work to be performed may be located in an awkward location and require the special positioning of the tool and its stabilizing means. 
   Prior devices have had torque-absorbing arms which can be detachably attached to the tool at a ninety-degree (90°) angle to the axis of rotation. In some cases such attachment is to a single location and in still others to a number of selected positions annularly or circumferentially of the axis of rotation. Almost all of such devices require the threading and un-threading of a handle into a selected opening. None of such devices permit the angular adjustment of the handle relative to the axis of rotation and also the circumferential or annular adjustment to selected positions around the axis of rotation. 
   SUMMARY OF THE INVENTION 
   The present invention makes adjustment possible of both the angle of the handle and its annular position relative to the tool or its attachments with a single control without the need to remove any parts from the tool. 
   It is an object of the invention to provide a stabilizer arrangement for an attachment for power tools in which the arm can be adjusted at various angles in any one of multiple positions selected circumferentially of the axis of the drive of the tool. 
   It is a further object of the invention to provide a stabilizer arrangement for a power head for a tool in which multiple positions of the stabilizer arm are achieved with a single control in the form of the stabilizer arm. 
   The objects of the invention are obtained by an accessory for power tools in which a housing supporting an input shaft and an output shaft are connected together with the input shaft being adapted for detachable attachment to a power tool and the output shaft being adapted for a detachable attachment to a working tool such as a screw driver or a nut driver. The housing supports a stabilizer assembly having an annular collar supported on the exterior of the housing for movement annularly in a first plane to selected indexed positions relative to the axis of the input shaft and a stabilizer arm supported on the collar for movement together of the collar to selected angular positions in a second plane perpendicular to the first plane and relative to the axis of the input shaft and lock means operable between a selected lock position holding the collar and arm stationary relative to said housing and an unlocked position permitting movement of the collar and arm as a unit to selected annular positions relative to housing. The stabilizer arm is lockable in a selected one of the angular lock positions at each of the selected positions of the stabilizer collar. 

   
     DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a longitudinal cross-section rotary tool attachment including a stabilizer embodying the invention; 
       FIG. 2  is a cross-sectional view taken generally on line  2 — 2  in  FIG. 1  at an enlarged scale; 
       FIG. 3  is a perspective view of the tool attachment showing one position of adjustment; 
       FIG. 4  is a generally diagrammatic view of a top view of the attachment showing various positions of angular adjustment of the stabilizer arm; 
       FIG. 5  is an end view showing various annular positions of the stabilizer arm relative to the longitudinal axis of the input shaft; and 
       FIG. 6  is a view showing the attachment and rotary tool positioned relative to the left hand of an operator. 
   

   DETAILED DESCRIPTION 
   The drive head of the invention is designated generally at  10  and is adapted for attachment to powered rotary tools such as drills or screwdrivers a portion of one being indicated at  11  in  FIG. 6  in which one hand of an operator can align and steady the drive head  10  and the other hand holds and triggers the drill  11 . The head  10  is connected to such drills or drivers by way an input shaft  12  and is suitable for driving quick release drills or fastener drivers by way of a quick release output chuck  14 . 
   The drive head  10  includes a housing  16  which serves to support miter gears  18  and  20  as seen in  FIG. 1  which change direction of drive from the tool motor a full ninety degrees (90°) from the input shaft  12  to the axis of output chuck  14 . 
   Miter gear  18  forms part of an output assembly  22  which includes chuck  14  and a stub shaft  24  extending from one face of miter gear  18 . The opposite face of miter gear  18  has a shaft extension  26  journaled in a ball bearing unit  28  and supports the quick release chuck  14  which typically would support a one-quarter inch (¼″) accessory or working tool such as a hex drill bit or hex screw or nut driver. The output assembly  22  is supported in housing  16  with stub shaft  24  rotatably seated in a complementary blind bore  30  formed in an interior wall of the housing  16  and with the outer face of bearing  28  pressed into a complementary annular recess  32 . The entire output assembly  22  is held within and relative to the housing  16  by a snap ring  34  seated in an internal annular groove in the output opening of the housing  16 . 
   The other miter gear or input gear  20  is identical to the output miter gear  18  and is fixed to one end of the drive shaft  12 . The other end of the drive shaft is provided with a stepped chuck receiving stem portion  36  for receiving a conventional three-eighths (⅜) collet chuck or a smaller diameter portion  37  for receiving a one-quarter inch (¼″) bit chuck commonly found on powered drills and screwdrivers. 
   The miter gear  20  and the drive shaft  12  is supported within the housing  16  by a shaft sleeve  38  which forms an extension of the housing  16 . The sleeve  38  has an enlarged head portion  40  that fits within an input opening  41  to the housing  16 . The enlarged head portion  40  is provided with an axially extending key portion  42  which is seated in a slot  44  formed in the housing  16  to prevent rotational movement of the sleeve  38  relative to the remainder of the housing  16 . The drive shaft  12  is provided with a ball bearing assembly  46  adjacent to miter gear  20  which is seated within the housing and is held axially in position by the head portion  40  of sleeve  38 . An intermediate portion of the drive shaft  12  is received in an opening  48  in the end of sleeve  38  opposite to the head  40 . The entire input drive assembly which is made up of the drive shaft  12 , miter gear  20 , ball bearing  46  and sleeve  38  is held in position relative to housing  16  by a snap ring  50  seated in an internal annular groove in the input opening  41  to housing  16 . 
   The stabilizer system for the driver head  10  includes a stabilizer collar  60  which is rotatably supported on the exterior of the housing  16  for a three hundred sixty degree (360°) rotation movement to selected indexed positions relative to the input axis of the drive shaft  12  and a stabilizer arm  62  mounted on the collar  60 , so that it can be moved to selected angular positions relative to the axis of the input shaft  12  of the drive head  10 . The stabilizer collar  60  is generally tubular and has an annular wall  61  at one end that acts to cover the input opening  41  of the housing  16 . 
   The stabilizer arm  62  has a covered handle portion  63  with a threaded blind bore  64  at one end to receive the complementary threads on a stud  65  extending radially from a head portion  66 . The head portion  66  is mounted on the intermediate portion of a pivot pin  67 . The pivot pin  67  is supported with its axis extending tangentially on the tubular collar  60  by a pair of spaced bracket members  68  as seen in  FIG. 3  receiving opposite ends of the pivot pin  67 . 
   The head portion  66  also has a rectilinear support base  69  at the inner end of the stud for supporting a pawl washer or pawl element  70 . The base member  69  extends radially from the head portion  66  to receive the pawl washer  70  having a complementary rectilinear opening to receive the rectilinear base portion  69 . This prevents rotation of the pawl washer  70  about the axis of stud  65  but permits axial movement. 
   The brackets  68  supporting the opposite ends of the pivot pin  67  are arcuate in shape and each is provided with rounded teeth  72  that are transversely aligned with each other and are adapted to engage complementary rounded teeth  74  formed on the pawl element or washer  70 . 
   The pawl washer  70  is normally held in position on the threaded stud  65  in a clamped position between the arm  62  and the pair of bracket members  68 . In that position the stabilizer arm  62  is clamped in the fixed position relative to the collar  60 . To change the position of the stabilizer arm  62  it is unthreaded a slight amount on the stud  65  to unclamp the pawl element  70 . The arm  62  can then be pivoted or indexed to selected positions. To lock the arm  62  in a fixed position, the arm  62  is rotated on the threaded stud  65  so that the complementary teeth  74  on the pawl and teeth  72  on brackets  68  are gradually brought into engagement with each other and gradually into alignment or mesh with each other because of the rounded teeth. This feature obviates the need for a detent mechanism to assure alignment of the teeth upon tightening of the handle  63 . 
   The head portion  66  of the stabilizer arm  62  also forms a locking cam  78  by which the stabilizer collar  60  can be fixed in selected positions circumferentially or annularly of the input axis of the drive shaft  10 . As seen in  FIG. 1 , cam portion  78  protrudes through an opening  80  in the wall of the collar  60  formed between the pair brackets  68 . Locking cam is shaped to engage with lock notches or recesses  82  formed on the outside of housing  60  and uniformly spaced circumferentially adjacent to the opening  48 . 
   The cam head  66  also is provided with a flat portion  86  seen in  FIGS. 1 and 4 . When the flat portion  86  is in alignment with the opening  80  in the collar  60 , the collar can be rotated relative to the housing  16 . However, when portions of the cam  78  protrude through the opening  80 , the cam portions  78  are disposed in one of the lock recesses  82  in the housing  16  to prevent movement of the collar  60  which is fixed in the selected position. 
   When the arm  62  is used to pivot the head  66  to a position where the flat surface  86  is in alignment with the opening  80  as would occur at position  96  of the arm  62  in  FIG. 4 , the collar  60  may be rotated or indexed to a selected one of twelve positions as illustrated in  FIG. 5  at  87   a  through  87   l.    
   The selected annular positions of the collar  60  relative to the housing  16  are determined by a detent arrangement in which a leaf spring  88  ( FIG. 2 ) is seated in a cavity  90  formed on the exterior surface of the input side of the housing  16 . The leaf spring  88  is held against rotation in the cavity  90  and its opposite ends form detent elements  92  adapted to engage the notches in detent recesses  94  that are formed on the inside surface of the stabilizer collar  60 . In the preferred embodiment of the invention the detent recesses  94  are twelve in number and are uniformly spaced so that when collar  60  is rotated relative to the housing  16  the collar is indexed to one of twelve positions or every thirty degrees (30°). In like manner, lock slots  82  in the outer circumferential surface of the housing  16  at the input end are also twelve in number and spaced every thirty degrees (30°) of the circumference. The detent spring  88  and it&#39;s complementary detent recesses  94  are in alignment with lock recesses or notches  82  in the housing  16  so that rotation of the stabilizer collar  60  to any of its twelve positions relative to the housing  16  will also place the corresponding lock slots  82  in alignment with the opening  80 . Subsequent pivoting of handle  12  from its unlocked position at  96  in  FIG. 4  will bring the lock cam or surface  78  into alignment and engagement with the corresponding slot  82  in the housing  16  to prevent rotation of the collar  60  from that selected annular position. Subsequent turning of the arm  62  while holding it in the selected angular position locks the collar  60  and arm  62  and places the power head  10  in condition for use. 
   It will now be seen that the stabilizer collar  60  can be indexed or adjusted to twelve radial positions around the input axis. In addition the arm or handle  62  can be adjusted to any one of five positions which includes the unlocked position indicated by dash line at  96  and four locked positions indicated at  97 ,  98 ,  99  and  100 . In the first or unlocked position at line  96  the flat surface  86  on head portion  66  on pawl washer  70  will be in alignment with the opening  80  and no part of the arcuate cam or lock portion  78  will protrude through the opening  80  so that the collar  60  can be indexed or rotated to any of its twelve positions. In a selected annular position of collar  60 , pivoting of arm  62  to any of its other four angular positions indicated at  97  through  100  will lock the collar  60  in its selected location. 
   With the arm  62  un-threaded a few turns as indicated by the arrow  101  in  FIG. 4  to release the pawl washer  70 , the arm can be pivoted from the unlocked position to a first locked position at  97  in which the arm is at a ninety degree (90°) angle to the axis and the input shaft. Movement of the arm  62  to the next position  98  in which the teeth on the pawl washer and the teeth on the brackets  68  are in alignment with each other would be at approximately sixty degrees (60°). Similarly, a third position  99  is at thirty degrees (30°) to the input axis and a fourth position  100  locates the arm  62  parallel to the drive axis. In any of these selected angular positions, the handle or arm  62  can be twisted or rotated in a tightening direction to move the arm  62  against the pawl washer  70  to bring its teeth  74  into tight engagement with the teeth  72  on the brackets  68  to hold the arm both annularly and angularly locked. 
   The stabilizer collar  60  can be adjusted to twelve circumferential positions in a first plane perpendicular to the input axis of the power head  10  as seen in all of the Figure drawings and the arm  62  can be locked in anyone of four angular positions for every thirty degrees (30°) between a parallel position and a ninety-degree (90°) position relative to the input axis of the power head  10  and in a second plane perpendicular to the first plane. This makes for 48 different locked positions of the stabilizer arm  62 , which can be twisted to engage and release the mating rounded teeth  74  of the pawl washer  70  and the teeth  72  on the brackets  68 . 
   One of the multiple stabilizer arm positions is illustrated in  FIG. 6  in which the arm is at approximately thirty degrees (30°) as illustrated at position  99  in  FIG. 4  and the stabilizer collar  60  has been indexed to position  87   b  in  FIG. 5  for positioning the apparatus  10  in the left hand of the operator to absorb torque and leave the right hand free to support and operate the power tool such as a drill motor or powered screw driver. 
   A stabilizer apparatus for a power head attachment for rotatable power tools has been provided in which a stabilizer arm can be positioned in a selected one of a plurality of positions around the input axis of the attachment and in each one of those positions can be moved to one of four angular locked positions all by simply twisting the arm to permit unlocking followed by selected movement of the arm to the desired position and subsequently twisting the arm to return it to a locked position.