Abstract:
A multi-sized clamp capable of attaching to various sized cylindrical objects such as iris rods of a professional movie camera. The multi-sized clamp includes a pair of clamp jaws connected by a hinge and a pivotable adjustment rod. The clamp jaws&#39; interior surfaces include curved surfaces having at least two different diameters. The clamp jaws are opened by turning the pivotable adjustment rod in one direction and closed by turning it in the opposite direction. One of the clamp jaws also contains a body that also has an opening and an L-shaped split above the opening with a closing mechanism running through the body above the opening and through the split. The closing mechanism when turned in one direction increases the opening and decreases the opening when turned in the opposite direction, thus allowing other equipment to be attached to the clamp through the opening.

Description:
BACKGROUND OF THE INVENTION  
         [0001]    The field of the present invention relates to a clamp for attaching a device to a cylindrical object. In particular, the invention relates to a clamp capable of attaching various devices to cylindrical objects of various diameters.  
           [0002]    In the entertainment industry, motion picture cameras typically have many different accessories attached to them in order for the cameras to capture the images that are desired. Typical accessories are lens lights, flags, LCD monitors and lens drive assemblies and motors. These accessories attach to the iris rods found on the front of the cameras. These accessories typically have built in clamps that are sized to a specific sized cylindrical object. Since the clamps on these accessories are sized to a specific cylindrical object, when the cylindrical object is of a different size, a different accessory is required that will fit that cylindrical object.  
           [0003]    Other accessories have clamps that are replaceable, such that when the clamp currently on the accessory is of a different size than the iris rod on the camera, the clamp can be removed and replaced with a clamp of the appropriate size. This, however, requires a selection of clamps to be on hand so that the accessory can fit any camera that is used.  
           [0004]    Since different camera manufacturers use different sized iris rods on their cameras, switching all of the accessories or the replaceable clamps on the accessories that may be on a camera at a given point in time to fit the different iris rods is an undesirable step. Also, this requires a camera rental company to maintain a large inventory of different sizes of clamps or a large inventory of accessories with integral clamps of varying sizes. Thus, it has been desirable to have a clamp that can fit varying sizes of iris rods to avoid having to replace the accessories or the replaceable clamps that attach to the accessories. Having a clamp that can fit varying sizes of iris rods is also desirable because it is less expensive than having a number of accessories or clamps. Therefore, a clamp that is capable of clamping to iris rods of several different sizes would be more economical and efficient and would reduce the number of accessories required.  
           [0005]    Furthermore, equipment that is clamped onto cylindrical objects typically is sized to fit a specific sized cylindrical object. Like with the accessories that are attached to movie cameras, other equipment either has integral clamps that are sized to a specific diameter or have a clamp that is replaceable when a larger or smaller diameter clamp is needed. This is also inefficient, as it requires either having inventory of equipment in stock that will fit a specific cylindrical object, or an inventory of clamps of varying diameters to fit each specific cylindrical object. Thus there is also a need to have a clamp that can fit cylindrical objects that can be attached to any piece of equipment such that the clamp can fit onto varying sizes of cylindrical objects.  
         SUMMARY OF THE INVENTION  
         [0006]    The present invention provides an improved clamp for attaching objects to cylindrical objects of varying diameters. The multi-size clamp of the present invention includes a pair of clamp jaws connected by a hinge and a pivotable adjustment rod assembly. The clamp jaws contain interior curved surfaces with the curved surfaces having curves of at least two different diameters. These curved surfaces are used to attach the clamp to at least two different diameters of cylindrical objects, such as iris rods on a movie camera.  
           [0007]    The cylindrical object is placed into the clamp with one of the clamp jaws in the open position. Once the cylindrical object is in place, the clamp is closed around the object using the pivotable adjustment rod assembly. As the pivotable adjustment rod assembly is rotated, one of the clamp jaws is forced downward toward the cylindrical object until the clamp jaw comes into contact with the cylindrical object and thus locks the clamp in place on the cylindrical object. When the pivotable adjustment rod assembly is rotated the opposite direction, the clamp jaw is opened and the clamp is released from the cylindrical object.  
           [0008]    One of the clamp jaws also contains a body that is provided with an attachment clamp. The attachment clamp in the body of the clamp jaw consists of an opening with the body split such that the opening can be increased and decreased. A closing mechanism runs through the body of the clamp jaw above this opening such that when it is rotated in one direction, the opening is enlarged and when it is rotated in the opposite direction, the opening decreases. This allows equipment to be attached to the clamp. An example would be a lens light that could be attached to the clamp and the clamp then attached to the iris rod on the front of a camera. However, the clamp can also be used to attach just about any other piece of equipment to it such that the piece of equipment has a means for fitting in the opening in the body of the clamp jaw.  
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0009]    [0009]FIG. 1 is an isometric view of the multi-sized clamp in the open position;  
         [0010]    [0010]FIG. 2 is a side elevation view of the multi-sized clamp in the open position;  
         [0011]    [0011]FIG. 3 is an isometric assembly view of the multi-sized clamp showing how one clamp jaw is connected to the other clamp jaw;  
         [0012]    [0012]FIG. 4 is a sectional view taken along line  4 - 4  from FIG. 1;  
         [0013]    [0013]FIG. 4A is a partial sectional view of the pivotable adjustment rod assembly;  
         [0014]    [0014]FIG. 5 is a side elevation view of the clamp in the closed position around the smallest diameter rod  
         [0015]    [0015]FIG. 6 is a side elevation view of the clamp in the closed position around a larger diameter rod;  
         [0016]    [0016]FIG. 7 is a side elevation view of the clamp in the closed position around the largest diameter rod;  
         [0017]    [0017]FIG. 8 is a partial sectional view taken along line  4 - 4  from FIG. 1, with the clamp in the fully open position; and  
         [0018]    [0018]FIG. 9 is a partial sectional view taken along line  4 - 4  from FIG. 1, with the clamp in the closed position. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0019]    The preferred embodiment of the present invention will now be described with reference to the drawings. To facilitate the description, a reference numeral representing an element in one figure will represent the same element in any other figure.  
         [0020]    Referring now to FIG. 1, the multi-sized clamp  10  is shown in the open position. The multi-sized clamp  10  includes a lower clamp jaw  12  and an upper clamp jaw  14 . The lower clamp jaw body  28  preferably has a clamping mechanism  16  for attaching equipment, such as lens lights, flags, LCD monitors, lens drive assemblies or motors or any other type of equipment (not shown), to the multi size clamp.  
         [0021]    Referring also to FIGS. 2, 3 and  4 , the clamping mechanism  16  consists of an opening  20  at the bottom of the lower clamp jaw body  28 . The lower clamp jaw body  28  is split in an inverted L-shape  24  above the opening  20 , allowing the side  26  of the lower clamp body to extend outward such that the opening  20  can be allowed to expand and be decreased in size by a closing mechanism  22 , as best viewed in FIG. 4. A rod  18  can be inserted into the opening  20  of the clamping mechanism  16  when the closing mechanism is in a released position such that the opening  20  is allowed to expand and increase in size to allow the rod  18  to pass through the opening  20 .  
         [0022]    The closing mechanism  22  includes of a threaded spindle  110  and a screw  115 . The lower clamp jaw body  28  has a hole  125  through it perpendicular to and above the opening  20 , which passes through the inverted L-shaped split  24 . A portion  125 A of the hole  125  is a small diameter hole through the left portion of body  28  (as viewed in FIG. 4) with clearance for spindle  110 . Both sides of the hole  125  preferably are counterbored so that the outer portion  126  of the hole  125  has a larger diameter than the interior portion  125 . A portion  125 B of the hole  125  on the right hand side of the lower clamp jaw body  28  opposite the inverted L-shaped split  24  can be threaded so that the threaded spindle  110  threadably engages directly (not shown) with the lower clamp jaw body  28 . However, it is preferred that the portion  125 B of the hole  125  on that side of the lower clamp jaw body  28  opposite the L-shaped split  24  be larger than the smaller portion  125 A of the hole  125  on the other side of the lower clamp jaw body  28  and threaded for receiving an insert  120  threadably engaged with this portion  125 B of the hole  125 . The insert  120  has external threads and also a threaded hole through the insert.  
         [0023]    The spindle  110  is an externally threaded rod with a threaded hole at one end of the rod. The spindle  110  is sized such that it will threadably engage with either the afore-described threaded portion (not shown) of the hole portion  125 B or the threaded insert  120 . A spindle handle  129  is attached to the spindle  110  opposite the end of the rod with the threaded hole. Once the spindle  110  is inserted into the hole  125  and threadably engaged with the threaded insert  120 , the screw  115  is then threadably engaged with the spindle  110 , securing the spindle from becoming unthreaded from insert  120 . The screw  115 , however, could be in the form of any other mechanism to prevent the spindle from being removed from hole  125 , such as a retaining ring or nut. The spindle  110  can then be rotated either direction using the spindle handle  129 . The spindle handle  129  has a base portion sized to fit within the larger portion  126  of the hole  125 . When the spindle  110  is turned in one direction, the spindle moves inward through the threaded insert  120 . The base portion of the spindle handle  129  comes into contact with side  26 , inside the larger portion of the hole  126 , thus forcing side  26  inward. This inward movement of side  26  decreases the opening  20  thereby engaging the sides of the opening  20  with the rod  18  which secures the clamp to the rod  18  and prevents any further movement of the clamp either around or along the rod  18 . When the closing mechanism  22  is turned in the opposite direction, the opening  20  is allowed to increase in size, thereby releasing the sides of the opening  20  from the rod  18  which allows the clamp to move along the rod  18 . Other equipment or clamps can be attached to rod  18 , such as lens lights, flags, LCD monitors, lens drive assemblies or motors, or any other type of equipment.  
         [0024]    The lower clamp jaw body  28  has a hole  30  through the body  28  above the clamping mechanism  16  and below the lower clamp jaw  12 . This hole  30  is used to decrease the weight of the lower clamp body, but does not reduce the strength of the lower clamp jaw body  28 .  
         [0025]    Referring now to FIG. 3, the lower clamp jaw  12  and upper clamp jaw  14  are shown in a disassembled state. The lower clamp jaw  12  has an interior curved surface  32 . The curved surface  32  has curves of at least two diameters. In the preferred embodiment, the interior curved surface  32  has curves of three different diameters. The smallest diameter curved surface  100  is generally in the middle of the lower clamp jaw interior surface  32 . Next, a pair of curved surfaces  102  have a diameter that is larger than the smallest diameter, but smaller than the largest diameter. The curved surfaces  102  are on each side of curved surface  100 . The curved surfaces  102  are substantially smaller in area than the curved surface  100 , but occur at two locations on the interior curved surface  32 . The largest diameter curved surfaces  104  are on each side of the curved surfaces  102 . In the preferred embodiment, there are three curved surfaces and the diameters of each of the curved surfaces are 0.590 inches, 0.620 inches and 0.748 inches, which are the sizes of three conventional iris rods for cameras, however, the curved surfaces  100 ,  102  and  104  can be of any diameter. Additionally, the clamp could be made with only two curved surfaces and any combination of two of the three different diameters could be used in a clamp with only two curved surfaces.  
         [0026]    The surface  130 , above interior surface  32 , has a generally U-shaped slot  34  cut into the surface. The slot  34  does not cut all the way through the lower clamp jaw  12 . The slot  34  starts above the end of the last curve  104  on surface  130  and extends to the top of the lower clamp jaw  12 . At the top of the lower clamp jaw, the slot extends completely through the lower clamp jaw  12 .  
         [0027]    On each side of the slot  34 , there are first holes  36  and second holes  38 . The first holes  36  are for a hinge pin  37  (shown in FIGS.  4 - 7 ), used to connect the lower clamp jaw  12  to the upper clamp jaw  14 . The second holes  38  are provided for a pivot pin  40  (shown in FIGS.  4 - 7 ).  
         [0028]    The upper clamp jaw  14  also has an interior curved surface  44 . The curved surface  44  has curves of at least two diameters. In the preferred embodiment, the curved surface  44  has curves of three different diameters. The curved surfaces  100 ,  102  and  104  of the interior curved surface  44  are the same as those for the lower clamp jaw  12  interior curved surface  32 . On the side of the upper clamp jaw  14  which connects to the lower clamp jaw  12 , the upper clamp jaw narrows below the end of the last curved surface  104 , such that the narrow portion  46  of the upper clamp jaw  12  can fit inside the slot  34  of the lower clamp jaw  12 . The narrow portion  46  of the upper clamp jaw  14  contains hole  36 . When the upper clamp jaw  14  is connected to the lower clamp jaw  12  by the hinge pin  37 , the holes  36  in both the upper clamp jaw  12  and lower clamp jaw  14  are aligned along centerline  48 .  
         [0029]    The upper clamp jaw  14  also contains holes  42 , which are sized to fit the keeper clamp  50  (shown in FIG. 4). The side opposite the interior curved surface  44  of the upper clamp jaw  14  also has a channel  54  cut into the upper clamp jaw  14  as can be seen in FIG. 1. The channel  54  allows for the movement of the pivotable adjustment rod assembly  60  as the upper clamp jaw  14  is opened and closed.  
         [0030]    The pivotable adjustment rod assembly  60  comprises several interconnected components that are similar in the two embodiments shown, but differ in some details. The main component of the assembly is the spindle  62 . The spindle  62  is a threaded rod. One end of the rod is narrower than the rest of the rod. The narrow end  62   a  of the spindle  62  contains an axially extending threaded hole. The end opposite the narrow end  62   a  of the spindle  62  has a handle  64  so that the spindle can be easily rotated in either direction. The screw  66  is sized so that it is threadably engageable with the hole in the narrow end  62   a  of the spindle  62 . The length of the narrow end  62   a  differs for the two embodiments shown. The head of the screw  66  is preferably slotted such that a flat head screwdriver can be used to turn the screw  66 . However, the screw head could be made to fit any type of screwdriver or wrench. Additionally, in place of the screw  66 , any other mechanism could be used which will secure the spindle  62  in place, such as a retaining ring or nut, but will allow rotation of the spindle  62 . The pivot pin  40  is inserted into the holes  38  in the lower clamp jaw  12 . The pivot pin  40  contains a threaded hole through the center of the pivot pin  40 . This threaded hole is sized to match the threaded rod portion of the spindle  62 .  
         [0031]    In the preferred embodiment shown in FIGS. 4 and 4A, the keeper clamp  50  is inserted into the holes  42  in the upper clamp jaw  14 . The keeper clamp  50  contains a hole sized to fit a non-threaded, smooth portion of the screw  66 , whereby the screw  66  does not threadably engage with the keeper clamp  50 . This hole is in the center of the keeper clamp  50 . The screw  66  is inserted through this hole after the keeper clamp  50  is inserted into the upper clamp jaw  14 . The side of the keeper clamp  50  that engages with the head of the screw  66  is flattened to provide a better contact surface. The side opposite this flat section of the keeper clamp  50  contains either a larger diameter countersunk hole or in the alternative, a flat section. This larger diameter hole only partially penetrates the keeper clamp  50  and is sized such that the narrow end  62   a  of the spindle  62  can fit inside that countersunk opening and the end of the spindle comes into contact with the keeper clamp  50 . Once the pivot pin  40  and the keeper clamp  50  are inserted into the lower clamp jaw  12  and upper clamp jaw  14 , the spindle  62  is threaded into the pivot pin  40  and positioned against the keeper clamp  50  respectively. The threaded end of the screw  66  can then be inserted through the hole in keeper clamp  50  and threadably engaged with the spindle  62 , securing the spindle in place, however, other means could be used to secure the spindle in place, such as a retaining ring or nut. The length of screw  66  and the depth of the threaded hole in spindle  62  are predetermined so that the screw  66  bottoms-out in the hole to establish a predetermined space between the screw head and the end of the spindle. This predetermined space allows free rotation of the spindle  62  without any significant axial movement. Washers may be provided on either side of keeper clamp  50  for enhancing this ability to rotate spindle  62 . Once engaged, rotation of the spindle  62  will cause the upper clamp jaw  14  to either open or close, depending on the direction that the spindle  62  is rotated. As the spindle  62  is rotated in one direction, the spindle  62  moves toward the upper clamp jaw  14  and pushes against the keeper clamp  50 , which forces the upper clamp jaw  14  down toward the lower clamp jaw. This will cause the spindle  62  and the screw  66  to pivot downward toward the lower clamp jaw. The pivot pin  40  and the keeper clamp  50  are free to rotate in the holes  38  and  42  and thus allow the rotation of the spindle  62  and the screw  66 . In this manner, the alignment of the components of the pivotal adjustment rod assembly  60  is maintained.  
         [0032]    In the preferred embodiment of FIGS. 8 and 9, the keeper clamp  50  is inserted into the holes  42  in the upper clamp jaw  14 . The keeper clamp  50  contains a hole sized to fit the narrow end  62 a of the spindle  62 , such that the narrow end  62   a  of the spindle  62  passes completely through the keeper clamp  50 . Both sides of the keeper clamp are flattened or counterbored where the spindle  62   a  passes through. Washers  52  are placed on both sides of the keeper clamp  50  prior to inserting the narrow end  62   a  through the keeper clamp  50 . Once the narrow end  62   a  is inserted into the keeper clamp  50 , screw  66  is threadably engaged with the threaded hole in the narrow end  62   a  of the spindle  62  and, with the washers  52 , prevents any significant axial movement of the spindle  62  relative to the keeper clamp  50  while allowing relative rotation. The screw  66  can be replaced by any mechanism to secure the spindle  62  in this manner, such as a retaining ring or nut. The spindle  62  when turned by handle  64  will now threadably move through the pivot pin  40  in either direction without the screw  66  turning relative to the spindle  62 . When the spindle  62  is turned in one direction, the spindle  62  will move in a direction which draws the spindle  62  toward the direction of the handle  64  and will cause the upper clamp jaw  14  to open, as in FIG. 8. When the spindle  62  is turned in the opposite direction, the spindle  62  will move toward the upper clamp jaw  14 , thus pushing the upper clamp jaw  14  down toward the lower clamp jaw  12 , as in FIG. 9. The pivotable adjustment rod assembly  60  (spindle  62  etc.) will pivot relative to the lower clamp jaw  12  and upper clamp jaw  14  as the spindle  62  is rotated due to the freely rotatable pivot pin  40  and keeper clamp  50  within holes  38  and  42 . This pivoting allows the components of the pivotable adjustment rod assembly  60  to maintain their alignment.  
         [0033]    Referring now to FIG. 5, the multi-sized clamp  10  is shown in the closed position around a small diameter rod  70 . When the clamp is closed around a small diameter rod  70 , the interior curved surfaces  100  on both the upper and lower clamp jaws engage with the rod  70  in the locations shown by the arrows  72  in FIG. 5. In the preferred embodiment, the smallest diameter rod  70  is 0.590 inches and the interior curved surfaces  100  have a diameter of 0.590 inches. This small diameter, however, can be any diameter, such that it matches the diameter of the rod that it clamps to.  
         [0034]    As can be seen in FIG. 5, the pivotable adjustment rod assembly  60  is shown with the upper clamp jaw  14  in the closed position. The pivotable adjustment rod assembly  60  is shown rotated downward toward the lower clamp jaw  12 .  
         [0035]    When a larger diameter rod  80  is inserted into the clamp, the upper clamp jaw  14  does not rotate downward as far as with the smaller diameter rod  70 . The interior curved surfaces  102  on the upper and lower clamp jaw then engage the rod  80  at different points than with the smaller diameter rod  70 . The rod  80  engages the interior surfaces  102  of each of the clamp jaws at two spaced locations instead of one continuous location, as with the small diameter rod  70 , as can be seen in FIG. 6. The arrows  82  indicate the points that the rod  80  engage with the upper clamp jaw  14  interior curved surface  44  and the lower clamp jaw  12  interior curved surface  32 . The interior curved surfaces  102  are curved to match the diameter of the rod  80 . In the preferred embodiment, the curved surface diameter and the rod diameter are 0.620 inches, however, any diameter could be used such that the diameter matches the rod diameter and it is larger than the small diameter of the previous rod. The rod  80  only engages the upper and lower clamp jaws at the locations indicated by the arrows  82 . The rod does not engage with the interior curved surface  100  of the upper and lower clamp jaw. This clearance can be more clearly seen with the largest rod in FIG. 7.  
         [0036]    In FIG. 7, the clamp is engaged with the largest diameter rod  90  that can be placed in the clamp. The arrows  92  indicate the engagement points between the rod and the clamp. The rod  90  engages with the interior curved surfaces  104  on the upper and lower clamp jaws. The rod does not engage with the interior curved surfaces  100  and  102  where the diameters of the curved surface are smaller than the present diameter of the rod  90 . In the preferred embodiment, the diameter of the rod  90  and the interior curved surfaces  104  of the upper and lower clamp is 0.748 inches, however, any diameter can be used such that the rod diameter and the curved surface diameter at the engagement point are the same. The pivotable adjustment rod assembly  60  is rotated down toward the lower clamp jaw  12 , however, because the largest diameter rod  90  is engaged with the clamp, the pivotable adjustment rod assembly  60  does not pivot downward as much as with the smaller diameter rod  70 . The pivot pin  40  and the keeper clamp  50 , however, still allow the pivotable adjustment rod assembly  60  to maintain its alignment because they allow a full range of rotation about the pivot pin  40 , by rotating independently from the upper and lower clamp jaws.  
         [0037]    The surface  130  above the interior curved surface  32  of the lower clamp jaw  12  is angled away from the interior curved surface  32  as can be seen in FIGS.  5 - 7 . The side  140  of the upper clamp jaw  14  that is adjacent to the lower clamp jaw  12  is angled away from the lower clamp jaw  12  when the upper clamp jaw  14  is in the closed position, best shown in FIG. 5. This allows the upper clamp jaw  14  to rotate from the fully opened position to the fully closed position without coming into contact with the lower clamp jaw  12 . In the fully open position, the angled surface  130  of the lower clamp jaw  12  and the angled side  140  of the upper clamp jaw  14  are aligned and are almost in contact with each other, as shown in FIG. 2. As the upper clamp jaw  14  is rotated downward to engage the various size rods, the angled side  140  of the upper clamp jaw  14  moves further away from the angled surface  130  of the lower clamp jaw  12 . This allows the upper clamp jaw  14  to rotate from a fully closed position to a fully open position without any interference between the upper and lower clamp jaws.  
         [0038]    While embodiments and applications of this invention have been shown and described, it would be apparent to those skilled in the art that other modifications are possible without departing from the inventive concepts herein. For example, the clamp jaws  12  and  14  may be slidably or otherwise connected, rather than hinged, and the pivotable adjustment rod mechanism  60  may be in the form of any adjustment mechanism such as a hydraulic piston and cylinder, a ratchet mechanism or the like. The invention, therefore, is not to be restricted except in the spirit of the claims that follow.