WO1981003691A1

WO1981003691A1 - Variable position diffusion holder

Info

Publication number: WO1981003691A1
Application number: PCT/US1980/000795
Authority: WO
Inventors: W Williams
Original assignee: W Williams
Priority date: 1980-06-17
Filing date: 1980-06-17
Publication date: 1981-12-24
Also published as: EP0053607A1; AU6785481A

Abstract

An apparatus to adjustably hold a diffusion or filter in juxtaposition with a spotlight lens, attached directly to appurtenances on the light source. The device is comprised of an arm (36) attached on one end to the light at the side shields (22) by means of a mounting channel (24) and on the other end to an extension arm (54). A diffusion or filter (70) is positioned within a compression loop (62) on one end of the extension arm (54) and is adjustably positioned with threaded fasteners at each of the innerfaces by thumb screws and wing nuts.

Description

VARIABLE POSITION DIFFUSION HOLDER

TECHNICAL FIELD

This invention pertains to equipment stands and more particular to arms on heads attached directly to equipment for holding accessories. In the motion picture industry and photographic field it is required to hold diffusion and filter acces¬ sories in front of spotlights or floodlights to achieve the proper light density and chromatic quality. _ Such equipment requires stands or arms to hold them in align- ment and position.

BACKGROUND ART

Previously there have been numerous types of apparatus^' developed to hold diffusion and filter devices for photographic lights. Common prior art utilizes stands with clamp heads and single or double arms. These consist of a tripod base either of case metal or tubular legs juxtapositioned to nest for storage. The vertical member telescopes for height adjustment and the arm or arms are pivotally connected to the vertical member singly or in tandum. The basic problem with this type of holders is their massive size since they rest on the floor or ground and extend vertically upward^' to be in alignment with the light. The vertical member telescopes and as the lights are sometimes placed high above the floor one or two extension arms are required to reach the light source. Further, since the stands are independent of the lamp they require floor space immediately in front of the light which creates crowding. Also, adjustment of light and diffusion or filter require separate operations to achieve the proper effect of the light.

Other prior art includes booms with casters or wheels, also grip equipment permanently mounted in front of fixed stage illuminating light.

DISCLOSURE OF INVENTION

The invention provides a holder for positioning diffusions and filters to soften light and to achieve color balance when incandescent and arc lights are used for color filming. In many applications the lights con¬ tain shields on two or more sides consisting of hinged plates movably attached to the light on one end. These shields are known in the industry as "barn doors". These doors offer protection from unwanted side lighting effects and offer some light directing capabilities. The inven¬ tion utilizes these doors to attach a movable head with a rotatable arm for holding the diffusion. It will be noted that the state of the art diffusion consists of material such as scrims, spun glass, acetate or silk mounted on a frame, usually wire, with a round rod handle. The filters are of similar construction using gelatine or acetate such as dichroic or blue color covering the frame. The size is appropriate to the diameter of the light lens and the handle length varies. The invention grasps the handle with an extension arm attached to the head allowing com¬ plete movement and adjustment either parallel or angular in front of the light by manually operated fastening arrangements.

The problem of excess size peculiar to prior art is solved by utilizing an arrangement physically small enough to attach directly to the light. This eliminates stands with large bases heavy enough to maintain- their own upright stability.

The height problem is also solved by eliminating the necessity of a vertical member and double extension arms, as the apparatus is attached directly to the light "barn doors". The necessity of height adjustment becomes immaterial. As the diffusion holder is now integral, light difficulties in crowded floor space are completely elimi¬ nated. By adjusting the diffusion on the light in a convenient location_.and then relocating the entire spot¬ light assembly to its optimum position the problem of separate and remote adjustment is also solved.

An important object extends the flexibility of the system by allowing the use of multiple diffusions and filters at the same time. This may be accomplished by attaching the devices at various positions on the light barn doors. This allows further improvement by enhancing the intensity softening of the light and achieving the optimum chromatic effect.

A further advantage provides easy storage of the entire assembly as the arms dissemble into small pieces and are easily handled and stored. Its small size permits it to be carried in a pocket in contrast to prior art which has common stand heights of 101.6 cm (40 inches) and 121.9 cm (48 inches) in the retracted mode.

Still another object of the invention is to shorten the set-up time to assemble the diffusion to the lamp thus reducing the overall labor required to complete the light¬ ing system.

Yet another object greatly reduces the overall cost of the equipment and provides a simple trouble free system for holding the apparatus.

A further object provides a reduction in weight, as this type of portable equipment is used for filming on location where transportation,ccrsts become a major con¬ sideration especially when shipping by air. These and other objects and advantages of the present invention will become apparent from the subsequent detailed description of the preferred embodiment -and the claims taken-in conjunction with the drawings.

BRIEF DESCRIPTION OF DRAWINGS FIGURE 1 is a partial isometric view of the pre¬ ferred embodiment installed on the shield of a spotlight. FIGURE 2 is a partial side view of the arm retaine of the preferred embodiment removed from the assembly. FIGURE 3 is an isometric view of the preferred embodiment.

FIGURE 4 is a partial side view of the attaching head and arm retainer of the preferred embodiment.

FIGURE 5 is a partial isometric view of an embodi¬ ment installed on the shields of a spotlight.

FIGURE 6 is a partial isometric view of the clamp head of an embodiment with cutaway portions depicting the internal construction.

FIGURE 7 is a partial isometric view of the exten¬ sion arm with the central portion cutaway.

FIGURE 8 is a partial isometric view of a clamp head of another embodiment with cutaway portions depiσt- ing the internal construction.

FIGURE 9 is a partial isometric view of a clamp head of another embodiment.

FIGURE 10 is a partial isometric view of an extension spring. FIGURE 11 is a partial isometric view of another embodiment installed on the shields of a spotlight.

FIGURE 12 is an isometric view of an embodiment using two compression loops to couple. the junction of the retainer arm and the extension arm. BEST MODE FOR CARRYING OUT THE INVENTION

The best mode or preferred embodiment is shown in FIGURE 1. This FIGURE depicts 3, representative spotlight 20 having side shields 22 or barn doors as they are com¬ monly called in the industry. The invention will mount on any light source containing such shields or any ap¬ purtenances located in a similar manner having a relatively flat surface adjacent to the lens. The device is attached to the shield 22 with a mounting channel 24 best shown in FIGURE 4. The channel 24 has an inside leg 26, outside leg 28 and web 30. The outside leg 28 con- tains a threaded bore 32 substantially centrally located. The channel 24 may be of any rigid material such as metal, either extruded, cast or formed or it may be non-metallic in the form of thermo-plastic or the like with aluminum extrusion being preferred. A compression threaded fastener 34 is located in the bore 32 of the channel 24 and is shaped in thumb screw fashion. This fastener is rotated for adjustment and when the channel is placed over a barn door 22 the inside leg surface 26 is contigu¬ ous and planar .with the door 22 being compressingly engaged by the urging of the fastener 34. This technique allows the channel 24 to be mounted on almost any flat surface smaller than the distance between the legs 26 and 28. The fastener 34 preferably contains a flat surface on the head such as found on a thumb screw, however, it may be any configuration allowing manual adjustment such as hex head, slotted or Philips type or spring loaded to provide compression. A swivel socket may also be located at the terminus of the fastener 34 to allow the screw to turn while the socket remains stationary. An arm retainer 36 best depicted in FIGURE 3 and 4 is further attached to the channel 24 in swivel fashion with a bore 38 in a flat on one end. This hole or bore 38 is slightly larger than the fastener 34 and allows it to penetrate and rotate freely in one plane. Threaded fastening means 42 in the form of a wing, hex or square nut applies compression between the arm 36 and the channel 24. This function operates independent of the channel 24 mounting, allowing the channel to be installed first and the arm 36 adjusted thereafter. A full 360° rotation is allowed in this junction.

The arm 36 may be in any structural shape with a round tubular form being preferred of the same material as the channel 24. The other end of the arm 36 is a duplicate of the first end containing a flat surface 41 and a hole 44. A rotatable compression loop 46 in the form of a round inside clamp is attached to the arm 36 with fastening means such as a screw 48, washer 50 and wing nut 52, however, any suitable fastener may be used. The loop 46 provides an adjustable fastener as the in¬ side diameter decreases in size when the screw 48 and nut 52 are tightened providing a tensioning member.

An extension arm 54 shown in FIGURE 2 is inserted into this loop 46 consisting of a round structural member preferably tubular in construction of the same material as the .channel 24 with one end flatened 56 with a hole 58 centrally located threin. The other end of the arm 54 is either plain or has a flare 60 to prevent loss or inadvertent slipping out of the loop 46. The arm 54 is free to slide in the loop 46 making adjustment longitudinally and may rotate a full 360 axially. The flatened end 56 further contains a compressible diffusion retaining loop 62 of similar construction to the compres¬ sion loop 46. The loop 62 is attached to the arm 54 through the hole 58 with fastening means such as a bolt 64, washer 66, and wing nut 68. The loop 62 is configured so that the head of the bolt 64 butts against the outside loop termination and/or a lip 62a, as shown in FIGURE 2, to prevent the loop 62 from turning.

The loop 62 retains a diffusion or filter 70 which, in common practice, consists of material attached around a wire loop that is in turn twisted at the closed end and inserted into a metallic tubular handle. The diffusion 70 is adjusted longitudinally or axially in the loop 62 to achieve the desired effect or correction at the proper focal point. . Another embodiment, best illustrated in FIGURE 12, uses the same structural method attaching the apparatus to the barn door 22 with the channel 24 as described in the preferred embodiment and as shown in FIGURE 4. The difference in this embodiment is in the use of a "univer- sal joint" consisting of two compression loops to couple the junction of the retainer arm 36 and the extension arm 54. The joint comprises a first rotatable compression loope 131 in the form of a round inside clamp attached and secured to the arm 36; a second rotatable. compression loop 132 having a 90° upwardly extending lip on its top section and that is attached and secured to the arm 54; a first spacer 130 inserted in a threaded stud 133, be¬ tween the loop 131 and a first wing nut 52; a nut 133 located between the loops 131 and 132 and captively held by butting one side of the nut to the lip of loop 132; and a second spacer 62a inserted in the threaded stud 133 between the loop 132 and a second wing nut 52a.

When the apparatus is attached to the barn door 22 and the first wing nut 52 is loosened the arm 54 can be rotated a full 360 in a vertical plane and rotated in a horizontal plane as limited only by the extremities of the barn door 22. By loosening the second wing nut 52a the arm 54 can be further rotated a full 360° about the circumference of the loop 132. Once the arm 54 is cor- rectly positioned it is held in place by tightening both wing nut 52 and 52a.

Another embodiment, best illustrated in FIGURE 5, uses the same structural method of attaching the apparatus to the barn door 22 with a channel 24, except the compres- sion is provided by a threaded fastener 72 of extended length. A spacer 74 is utilized having a bore 76 running the length. This spacer 74 may be any convenient con¬ figuration with round being preferred.

A leaf bracket 78 is abutted to^' the spacer also containing a hole 80 throughout the length having the same inside diameter as the spacer 74. The bracket 78 is formed much as a single leaf of a hinge starting with a flat plate with one end rolled into a closed loop creat ing the hole 80. This leaf bracket 78 further contains a hole or bore 82 in the flat surface substantially near th surface opposite the closed loop. The spacer 74 and bracket 78 are aligned with the holes 76 and 80 and the threaded fastener 72 penetrates therein. This fastener 7 threadably engages the channel 24 on one end and alignes the bracket 78 and spacer 74 on the other and holds them compressibly with threaded fastening means 84 in the form of a wing nut, hex nut, square nut or the like. This fastener 84 provides independent adjustment of the leaf bracket 78 in angular displacement. The bracket 78 also includes a rotatably compression loop 86 consisting of an eye bolt 88 with the shank penetrating the hole 82 in the leaf bracket. This loop 86 consists of a channel shaped compression member 90 with a hole 92 in the web, essentially centrally located, through which the eye bolt 88 penetrates. There are also notches in each of the leg distal-proximate to the hole 92. This loop 86 is adjuste by a wing nut 94 or the like, and pulls the eye bolt 88 into the channel 90 for tensioning.

Another embodiment of the same assembly is shown i FIGURE 8 and consists of essentially the same components i.e. channel 24, leaf bracket 78 and loop 86. The only difference is that the- spacer 74 is replaced with a threaded standoff 96. This standoff has a similar bore 76 except one end is externally threaded and replaces the threaded fastener 72. This standoff is threadably received into the channel 24 and provides the compres¬ sion function. A thumb loop 98 penetrates the standoff 96 for rotating manually, however, any suitable projectio or configuration allowing a griping surface may be used. The end of the standoff 96 opposite the external threads is internally threaded 99 and receives a _.shortened threaded fastener 100 which has a head that may be

OMΓ manually rotated in thumb screw fashion applying compres¬ sion between the leaf bracket 78 and the standoff 96. The balance of the assembly operates in the same manner as formerly outlined in FIGURE 6. FIGURE 7 indicates an arm retainer 102 completing this embodiment. This arm 102 is inserted into the compression loop 86 of the leaf bracket 78 and consists of a round structural member, preferably tubular in construction of the same material as the channel 24. One end is flattened 104 with a hole 106 centrally located therein. The other end of the arm 102 is either plain or has a flare 108 to prevent loss or unwanted removal from the loop 86. The arm 102 is free to slide in the loop 86 making adjustment longitudinally and may rotate a full 360 axially. The flattened end 104 further contains a compression loop 86 attached in the hole 106 identical as shown and described in FIGURES 6 and 8. This loop 86 retains a diffusion or filter 70 and is adjusted in front of the light 20 lens as desired by tightening the wing nut 94 of the loop 86. The embodiment of FIGURE 5 as above described requires four separate manual adjustments to assemble the system in proper orientation. The threaded fastener 72 compresses the leg of the channel 24 to the barn door 22 and also holds the spacer 74 to the leaf bracket 78 with the wing nut 84. In the case of the FIGURE 8 embodiment the standoff 96 is rotated to attach to the barn door 22 and the thumb screw 100 to retain the leaf bracket 78. In both embodiments the loop 86 on the leaf bracket 78 tightens the arm 102 with the wing nut 94 and the second loop 86 on the arm is in turn tightened by the wing nut 94 holding the diffusion -70.

Another embodiment illustrated in FIGURE 11 utilizes the arm 102 and its associated loop assembly 86, however, the attachment to the barn door 22 is different. This embodiment does not require manual adjustment as it is spring loaded and holds itself in place through spring tension. The retaining head 108 best shown in FIGURE 9 is in substantial channel shape with a top leg 110 ex¬ tending beyond the bottom leg 112 having a slot 114 on one side of each leg. These slots 114 engage the edge of the barn door 22, as both are in alignment, only sligh axial pressure need to applied to wedge them angularly at the innerface of the door 22. The head 108 further contains a plurality of holes 115 to singally attach an extension spring 116. This spring 116 depicted in FIGURE 10 consists of a diametrical coil 118 and end loops 120. The first loop 120a attaches to one of the holes 115 in the head 108 and the second loop 120b attaches on the door 22 of the light 20. For ease of attachment a finger ring 122 is incorporated in the second end of the spring 116 with the spring wire formed circularJ-y around the rin 122 holding it in place. This embodiment is positioned with two manual adjustments of the head 108 loop retainer 86 and the arm 102 retaining loop 86 to accomplish the desired location of the diffusion 70. Although the invention has been described in complete detail and pictorally shown in the accompanying drawings it is not to be limited to such details since many changes and modifications may be in the invention without departing from the spirit and scope thereof hence it is described to cover any and all modifications and forms which may come within the la._-.g-_. .--*-. and scope of the appended claims.

Claims

1. _. A variable position diffusion holder demount- ably attached to an enclosed light source for engaging mounted filter and diffusion materials comprising:

(a) a mounting channel, having an inside leg surface contiguous with said light and an outside leg compressingly engaging the opposite surface of said light for removably attaching said channel to said light;

(b) an arm retainer having a bore on the first end planar with said channel and a rotatable com- pression loop on the second;

(σ) a compression threaded fastener positioned in said bore threadably engaging said mounting channel on one end providing compression to said light and threaded fasteneing means on the other providing compression to said retainer rigidly affixing therewith; and

(d) an extension arm having a compressible diffusion retaining loop on one end adjustably positioned within said rotatable compression loop for holding said diffusion or filter in proximity to said light.

2. The apparatus according to claim 1 in which said mounting channel further comprises; a channel having a threaded bore in said outside leg to rotatably engage said compression threaded fastener.

3. A variable position diffusion holder demount- ably attached to an enclosed light source for engaging mounted filter and diffusion materials comprising:

(a) a mounting channel having one inside leg surface contiguous with said light and an outside leg compressingly engaging the opposite surface of said light for removably attaching said channel to said light; (b) a spacer having a bore providing an ex¬ tended mating surface planar to said mounting channel;

(c) a leaf bracket having a bore and a distal proximate mounting surface being contiguous to said spacer having the bores in mating alignment providing a mounting surface;

(d) a compression threaded fastener positione within said leaf bracket and spacer bores threadably engaging said mounting channel on one end providing com- pression to said light, also threaded fastener means on the other end providing compression to said spacer leaf bracket and channel rigidly affixing therewith;

(e) an arm retainer threadably engaged into said leaf bracket having a first rotatable compression loop for attachment; and

(f) an extension arm with a second rotatable compression loop positioned within said arm retainer having a seond rotatable compression loop to adjustably hold said diffusion and filter materials.

4. The apparatus according to claim 3 in which said mounting channel further comprises a channel having a threaded bore in said outside leg to rotatably engage said compression threaded fastener.

5. The invention of claim 3 in which said leaf bracket further comprises a bracket having a bore to couple said arm retainer thereinto.

6. The invention as recfted in claim 3 wherein said arm retainer first rotatable compression loop further comprises an eyebolt compressionly engaging a channel retainer through said leaf bracket "bore for said arm retention.

7. The apparatus in accordance with claim 3 in which said extension arm second rotatable loop further comprises an eyebolt compressionly engaging a channel retainer and said extension arm having a bore with said bolt innerpositioned therin for said diffusion retention.

8. A variable position diffusion holder demount- ably attached to_an enclosed light source for engaging mounted filter and diffusion materials comprising:

(a) a mounting channel having an inside leg surface contiguous with said light and an outside leg

• compressingly engaging the opposite surface of said light for removably attaching said channel to said light;

(b) a threaded standoff having male threaded portion on the first end and a female threaded portion on the second end providing an extended mating surface planer to said mounting channel;

(c) a leaf bracket having a bore and a distal- proximate mounting surface being contiguous to said threaded standoff having the bores of the bracket and standoff in mating alignment providing a mounting surface;

(d) a compression threaded fastener positioned ^' within said leaf bracket threadably engaging the second end of said threaded standoff providing compression to said leaf bracket rigidly affixing it thereto; (e) an arm retainer threadably engaged into said leaf ^"bracket having a first rotatable compression loop for attachment; and

(f) an extension arm with a second rotatable compression loop positioned within said arm retainer to adjustably hold said diffusion and filter materials within said second loop.

9. The apparatus according to claim 8 in which said mounting channel further comprises a channel having a threaded bore in said outside leg to rotatably engage said threaded standoff.

10. A variable position diffusion holder demountly attached to an enclosed light source for engaging mounted filter and diffusion materials comprising:

(a) a retaining head in substantial channel shape with a top leg extended beyond the bottom leg havin a slot on one side of each leg for engaging said light also having portions defining a bore integral with said extended leg for compression attachment;

(b) an extension spring having a diametrical coil and end loops with the first end attached into said retaining head bore and the second end attached to said light source under tension positioning the head to the light;

(c) an arm retainer threadably engaged into said retaining head having a first rotatable compression loop for attachment;

(d) an extension arm with a second rotatable compression loop positioned within said arm retainer to adjustably hold said diffusion and filter materials within said second loop.

11. The apparatus according to claim 10 wherein said extension spring further comprises a ring affixed in a loop fashion onto said second end of spring adjacent to said loop for grasping manually when tensioning the spring onto said light.