Abstract:
A camera swing head includes a hub having a hole ring including a plurality of radially spaced apart holes. A swing plate is rotatably attached to the hub. An indexing and locking assembly allows the swing to be quickly and easily rotated to a desired position and then locked into place. The indexing and locking assembly may include a lever pivotally attached to the swing plate, and a plunger pivotally attached to a front end of the lever. Pivoting movement of the lever may move the plunger linearly on a radial axis intersecting a center of the hub. A release pin is movable from, a first position, wherein the release pin causes the plunger to be held out from engagement to with one of the radially spaced apart holes, to a second position, wherein the plunger is movable into engagement with one of the radially spaced apart holes.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    The field of the invention is camera swing heads. In motion picture or video filming, the camera is often mounted on a camera head, to allow the camera to be smoothly moved. Various types of camera head have been used including camera heads for moving the camera in pan and tilt axes and fluid heads that provide smooth and silent operation. Other types of camera heads are used to set up the camera in a desired position between filming sequences, or to achieve specific types of movement. Swing heads are used for this purpose to rotate or swing the camera on a swing plate about a fixed axis into a desired position, and then optionally lock the swing plate against further movement. Although various swing heads have been used, disadvantages remain in their design and use. It is an object of the invention to provide an improved camera swing head. 
       SUMMARY OF THE INVENTION 
       [0002]    In a new camera swing head, a hub has a plurality of radially spaced apart indexing holes. A swing plate is rotatably attached to the hub. An indexing and locking assembly allows the swing plate to be quickly and easily rotated to a desired position and then locked into place. The indexing and locking assembly may include a lever pivotally attached to the swing plate, and a plunger pivotally attached to a front end of the lever, with a plunger spring urging the plunger into one of the holes. Pivoting movement of the lever may move the plunger linearly on a radial axis intersecting a center of the hub. A release pin is movable from a first position, wherein the release pin causes the plunger to be held out from engagement with one of the radially spaced apart holes, to a second position, wherein the plunger is movable into engagement with one of the radially spaced apart holes. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0003]      FIG. 1  is a perspective side view of a camera leveling head. 
           [0004]      FIG. 2  is a side and bottom perspective view of the camera leveling head of  FIG. 2  with a swing head attached to the leveling head. 
           [0005]      FIG. 3  is a top perspective view of the swing head shown in  FIG. 2 . 
           [0006]      FIG. 4  is a top view in part section of the swing head shown in  FIG. 3 . 
           [0007]      FIG. 5  is a section view taken along line  5 - 5  of  FIG. 4 . 
           [0008]      FIG. 6  is a section view taken along line  7 - 7  of  FIG. 6 . 
           [0009]      FIG. 7  is an enlarged detail view of the section shown in  FIG. 4 . 
       
    
    
     DETAILED DESCRIPTION 
       [0010]    As shown in  FIG. 1 , a leveling head  22  is includes a level plate  42  attached to a base or nose plate  30  of a nose bracket  24  via a universal joint  38 . A nose arm  32  of the nose bracket may be attached to the arm or a camera crane or a camera dolly. The universal joint  38  allows the level plate  42  to pivot about lateral and longitudinal axes. The level plate  42  may be leveled using thumbwheels  36  attached to jack screws  34 . Bubble levels  44  may be provided on the level plate  42  to provide visual indicators of the position of the level plate  42 . 
         [0011]    As shown in  FIGS. 2 and 3 , a swing head  20  may be attached to the level plate  42 . Alternatively the swing head  20  may be attached directly to another supporting structure, without using the leveling head. As shown in  FIGS. 4 and 5 , the swing head  20  has a swing plate  52  rotatably attached to a hub  48 . The hub  48  may include a threaded stud  50 , allowing the hub  48  to be attached to the level plate  42  by passing a bolt tube  40 , shown in  FIG. 2 , up through holes in the nose plate  30  and the level plate  42 , with the bolt tube  40  threaded onto the stud  50  of the hub  48 . The threaded stud  50  may have a standard 2¾ diameter, with a key  71  on a bottom surface of the hub  48  engaging into a slot on the level plate  42 , or other supporting surface, to prevent the hub  48  from rotating. 
         [0012]    Referring once again to  FIGS. 4 and 5 , the swing plate  52  may be an oval, with straight sides and rounded opposite ends optionally having the same radius of curvature. A camera mounting fitting  54 , such as a Mitchell mount, is provided on the outer end of the swing plate  52 , typically centered on the circle defined by the radius R of the outer end  68  of the swing plate  52 . 
         [0013]    Referring to  FIG. 5 , an outer bearing  58  is positioned on or around a hole ring  70  on the hub  48 . A seal such as an o-ring may be used to provide a low-friction seal between the hub  48  and the swing plate  52 , to seal the outer bearing  58  from the environment. The outer bearing  58  may have a diameter equal to 85 to 100% of the outer diameter of the hub  48 .  FIG. 5  shows a design with the outer bearing  58  having a diameter equal to (i.e., 100% of) the outer diameter of the hub. This increase the load carrying capacity of the swing head  20 . 
         [0014]    The hole ring  70  has radially spaced apart holes  72 . The holes  72  may be tapered holes and may also be evenly spaced apart. Each hole  72  is aligned on an axis, or radius, extending through a swing axis  65 . An inner bearing  60  is positioned on or around a center post  55  on the hub  48 . The swing plate is rotatably attached to the hub via the inner and outer bearings  58  and  60 , which may optionally be pressed onto or into the hub or the swing plate  52 . A cap plate  62  may be secured over the inner bearing  60  using a cap bolt  64 , with cap pins  66  locking the cap plate  62  onto the center post  55 , and preventing the cap plate from rotating with the swing head. A o-ring or similar seal element may be lightly pressed into the gap between the cap plate  62  and the swing pate  52 , to seal the inner bearing  60  from the environment. The inner end  75  of the swing plate may have a radius of curvature R, equal to the radius of curvature of the outer end  68 . The swing plate  52  may have, a length equal to about 3-6 R, or longer, with the example shown having a length of about 3.5 to 4 R. 
         [0015]    As shown in  FIGS. 6 and 7 , a rotation indexing and locking assembly generally indicated at  75  allows the swing head  52  to be quickly and easily rotated to a desired azimuth position, and then locked into position. The assembly  75  includes a lever  74  pivotally attached to a side of the swing plate  52  on a pivot pin  76 . The pivot pin  76  may be attached to a lever bracket  90  that is attached onto the swing plate using bolts  92 . A plunger  78  may have a tapered inner end  98  and an outer end pivotally attached to front end of the lever  74  via a plunger pin  88 . A plunger spring  80  urges the plunger radially inwardly towards the swing axis  65 . A spring tube  96  may be threaded into the swing plate  52  to hold the plunger spring in place. 
         [0016]    Referring to  FIG. 6 , a cam or protrusion  86  is provided on the swing plate  52 , or on the lever bracket  90 , if used, and is shown in  FIG. 6  positioned centrally in between an upper arm  102  and a lower arm  104  of the lever  74 . A release pin  82  is captured within the lever  74  via release cap plate  94 . The release pin is urged outwardly (or down as shown in  FIGS. 2 and 6 ) by a release spring  84 . 
         [0017]    In use, the nose bracket  24  or similar accessory is attached to the arm of a camera support, such as a camera crane or camera dolly, optionally using the leveling head  22 . If the leveling head is used, the level plate  42  is leveled using the jack screws  34 . A camera is attached to the swing plate  52  via the fitting  54 . The swing head  20  has a very low profile. The swing plate  52  has a thickness AA in  FIG. 5  of about 0.5 to 1.0 inches. The hub  48  has a thickness or height BB in  FIG. 5 , of about 1.2 to 1.8 or 1.4 to 1.6 inches. The swing head  20  accordingly adds relatively little height to the vertical position of the camera. This can provide greater flexibility in positioning the camera as desired. 
         [0018]    The swing plate  52  is locked against rotation because the inner end of the plunger  78  is engaged and held into one of the holes  72  by the plunger spring  80 . The camera may be repositioned by pivoting or rotating the swing plate  52 . This is achieved by pushing the back end of the lever  74  inwardly, causing the inner end of the plunger  78  to withdraw from the hole  72 . With the plunger withdrawn, the swing plate  52  is free to rotate about the hub. When the swing plate  52  is rotated to the desired position, the lever  74  is released. The plunger spring  80  then drives the inner end of the plunger back into one of the holes  72 . If the plunger is not precisely aligned with a hole when the lever  74  is released, slight additional movement in either direction will perform the alignment, with the spring moving the plunger into a hole  72  when the plunger and the hole are sufficiently aligned. 
         [0019]    With the plunger  78  urged into a hole  72 , the swing plate  52  is locked, with no discernable play. The spring  80  may have a high spring constant, so that the plunger is forcefully pushed into the hole  72 . If the inner end  98  of the plunger  78  is tapered, or has a conical tip, and if the hole  72  has a complementary shape, the plunger  78  will securely lock the swing plate  52  against all movement, with no play. The lever  74  may have a long back section to provide sufficient leverage to allow the plunger to be withdrawn from the hole, without excessive hand force. For example, the back section of the lever  74 , from the pivot pin  76  to the back end, may be 2-6 or 3-4 inches. Under high loading conditions or other circumstances, it is also possible to pull out on the lever  74 , to further force the plunger  78  into the hole  72  of the hole ring  70  on the hub  48 . 
         [0020]    The release pin  82  and the cam  86  provide a release assembly  85  which may be used to hold the plunger  78  in a release position, without the need to continuously press the lever  74  inwardly. As shown in  FIGS. 6 and 7 , the release pin is normally held in the out position by the release spring  84 . When release pin is in the out position, the lever  74  may be pressed in to rotate the swing plate  52 , and released to lock the plate. 
         [0021]    To allow the swing plate  52  to rotate freely without holding the lever  74  in by hand, after the lever  74  is pressed inwardly, the release pin  82  is pushed in or up. Then, with the release pin in the in position, as the lever  74  is released, the release pin  82  moves into contact with the cam  86 . Although the release spring  84  continues to urge the release pin  82  outwardly, the friction force between the cam  86  and the side of the release pin  82  holds the pin in the up or in position. As a result, the lever is held in the in or release position, and the plunger is pulled back from the hole  72  in the hole ring  70 . The swing plate  52  can then rotate freely about the hub  48 . The swing plate  52  may then be rotated while the camera is filming or recording, to perform a so-called “free head” shot. Specifically, the camera is moved in a panning type of movement, but with rotation about a fixed axis several inches (e.g. 4 to 10 or 12 inches) apart from the lens axis. The inner and outer bearings provide for a smooth and quiet swing movement. 
         [0022]    The release assembly  85  is deactivated simply by pushing the lever  74  inwardly momentarily. As the lever  74  is pushed in, the release pin  82  moves away from the cam  86 . The release spring  84  then moves the release pin  82  back into the out position, since the friction holding force exerted by the cam  86  on the release pin  82  is removed when the release pin  82  is not held into contact with the cam. Referring to  FIG. 6 , when the release pin  82  is in the out position, it is below the level of the cam  86 . The lever  74  can therefore return to its original position, locking the swing plate. 
         [0023]    Thus, a novel camera swing head has been shown and described. Various changes and substitutions may of course be made without departing from the spirit and scope of the invention. The invention, therefore, should not be limited, except by the following claims and their equivalents.