US2421437A - Microphone boom - Google Patents

Description

June 3, 1947.

Filed Nov. l0, 1944 5 Sheets-Sheet l fw S z V N Q (i *Y T Q5 a lli N Q o d y Q mmm y R q QQ o 'Q l RR je R n N w Q Q LQ yeo/vFyA/w 5g M-,QSM/r/-g INVENTORS.

ATTORNEY.

`lune 3, 1947. B. F. RYAN ET Al.vk

MICROPHONE BOOM Filed NOV. 10, 1944 5 Sheets-Sheet 2 w. Fwm H M H l m.

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Nm. MW QM, QW Nm June 3; 1 947.

B. F. RYAN ET A1.

MICROPHONE BOOM Filed Nov. lO, 1944 5 Sheets-Sheet 5 E 5214/ TH, INVENTORS.

ATTORNEY.

June 3, 1947- B. F. RYAN ET Al.

MICROPHONE Boom 5 Sheets-Sheet 4 INVENTORS.

Filed Nov. l0, 1944 ATTORNEY,

June 3, 1947.y

B. F. RYAN x-:T AL

MICROPHONE BOOM Filed Nv. 1o, 1944 5 sheets-sheet 5 yA/V,

ATTORNEY.

Patented June 3, 1947 UNITED STATES PATENT OFFICE MICROPHONE BOOM Application November 10, 1944, Serial No. 562,800

15 Claims'.

This invention relates to booms, and particularly to the type of boom wherein a microphone is supported and variably positionable laterally, vertically, and rotationally.

Booms of the general type of this invention are Well-known, as evidenced by Mueller Patent No. 2,122,778, which shows a type of boom providing for the rotation of the microphone itself, the rotation and elevation thereof about a boom supporting standard, and the extension and retraction thereof away from and toward the standard. The boom of this patent utilizes a iixed counterweight, and the counterweight end of the boom is connected to the standard to maintain the crossarm in balance during adjustment of the microphone away from and toward the standard. In Goshaw Patent No. 2,235,518, a similar type of boom is illustrated, but one in which the counterweight is adjustable along the opposite side of the crossarm from the microphone to maintain the boom in balance during the extension and retraction of the microphone, this feature being of prime importance to the operator manipulating the microphone about a motion picture set. It will be noted that the booms of these patents are particularly sturdy, while the crossarms have considerable overhang on the counterweight side. In view of the length of the counterweight side of the crossarm, it is impractical and many times impossible to use such a boom within a room where the boom standard or vertical supporting column must be outside of the camera angle. In the past, the prior type of boom could only be used in small rooms by extending the crossarm through a window, this method being unsatisfactory becauseV the window limited the adjustability of the crossarm and the view of the operator.

One of the main features of the present boom, therefore, is an extensible boom structure which is counterbalanced at all times, which is sturdy and has all the controls of the usual boom, and which will occupy a minimum of space behind the boom support. This is accomplished by using a fixed counterweight which may he any desired size so that the minimum length of crossarm can be employed on the counterweight side, and by providing an adjustable counterweight on the microphone side of the crossarm. With the adjustable counterweight on the microphone side of the standard, when the inner telescopic section of the crossarm is extended, the counterweight travels toward the standard and vice versa to maintain the boom in perfect balance at all times. The boom is also provided with a particularly sensitive and accurate rotational control. The boom is mounted on a carriage or perambulator which may be expanded or contracted, both as to wheel base and tread, so as to be accommodated in a small space when necessary and which may be transported through narrow doors.

The principal object of the invention, therefore, is to facilitate the manipulation of a microphone about a motion picture set.

Another object of the invention is to provide a microphone boom having controls for rotational, lateral, and vertical adjustment, and which may be used within a small space such as small rooms.

A further object of the invention is to provide Y an improved microphone boom which is readily portable through small openings, and which will occupy the minimum amount of space.

A further object of the invention is to provide an improved rotational control for a boom supported microphone.

A still further object of the invention is to provide an improved microphone boom which has all the necessary controls arranged in a particularly convenient manner.

A still further object of the invention is to provide an improved boom and carriage therefor which will require the minimum of space for the operation of the boom. 'f

Although the novel features which are believed to be characteristic of this invention will be pointed out with particularity in the appended claims, the manner of its organization and the mode of its operation will be better understood by referring to the following description read in conjunction with the accompanying drawings forming a part hereof, in which:

Fig. 1 is a perspective view of a microphone boom and its perambulator embodying the invention.

Fig. 2 is a side View of the main portion of the microphone boom of Fig. 1.

Fig. 3 is a cross sectional view of the adjustable counterweight mechanism taken along the line 3-3 of Fig. 2.

Fig. 4 is a cross sectional view of the mechanism of Fig. 3, and taken along the line 4--4 of Fig. 3.

Fig. 5 is a plan view of the microphone boom of the invention.

Fig. 6 is a side view looking in the direction of the arrow 6 of Fig. 5.

Fig. '7 is a partial view illustrating the cable arrangement for extending and retracting the microphone.

Fig. 8 is a partial view illustrating the cable arrangement for rotating the microphone.

Fig. 9 is a partial view illustrating the cable arrangement for extending and retracting the counterweight.

Fig. 1() is a partial View illustrating the electrical transmission cable arrangement for the microphone.

Fig. 11 is a partial View illustrating the attachment of extending cable to the inner telescopic member of the crossarm, and taken along the line II-Il of Fig. 5.

Fig. 12 is a view of the elevating mechanism for the cross-arm taken along the line I2-I 2 of Fig. 2, and

Fig. 13 is a cross sectional view of the elevating mechanism taken along the line I3-I3 of Fig, 12.

Referring now to the drawings in which like numerals identify similar elements, and particularly to Fig. 1, the boom is supported and moved about by a three-wheeled carriage or perambulator 5 having a frame of tubular members and a platform 'l supporting a hollow tubular boom standard or mast il. The single castor wheel end of the perambulator has a handle Il for pulling and guiding it to any desired location. When the handle is raised to a vertical position, it is locked at 4 and applies a brake 3 to the tread of the castor wheel tire. U-shaped tubular members I2 are adapted to telescope in and out of tubular members I3 so that the perambulator or carriage may be contracted into the minimum of space commensurate with stability. Thumb screws lil hold members I2 fixed in any adjusted position. The tread of the perambulator is also adjustable so that wheels 8 and II may be separated to obtain stability during transportation and operation of the boom and brought together to permit passage through narrow doors or openings. The axes of wheels 8 and I I are not `coincident but parallel so that the axlesof the wheels may be moved in and out of parallel tubes and locked in position by set screws, one of which is shown at I4. An operators platform I5 is a'djustably mounted on the standard 9 and has anotch I6.at one end thereof .to accommodate the handle Ill when the carriage is contracted.

Within the hollow standard 9 is a slidable sleeve 19, (see Figs. 12 and 13) along which a, rack 20 is attached in Vany suitable manner, such as by screws 2 I. The sleeve I9 is raised or lowered when a handle 22 is turned torotate a shaft I'I carrying a worm 23 in mesh with a worm gear V2li. The rotation of the gear 24 rotates a pinion 25 in mesh with the rack 2.0, and thus moves the sleeve I9 up and downas desired. The pitch of worm 23 is such as to lockthis elevating mechanism in any adjusted position. For safety, however, the sleeve I9 is locked in any xed position by the hand set screw 2.1. To stabilize the sleeve I9 and to prevent its rotation, tubular cross members 28 are welded to the .upper portion of sleeve I9, the members Z8 having twov vertical extensions 29 which telescope in the vertical frame members Sil. Atelephone box 34 is shown mounted on one of the vertical stabilizing supports 28.

Continuing upwardly, the sleeve I9 is adapted to have inserted therein a pivot pin 37 whichpin also extends into a. casting having a lower shoulder portion 38. (see Fig. 6), and two parallel spaced crossarm pivot supporting hangers d5. The boom is thus rotatable about the axis of the pin 3l, and the pin may be locked to the sleeve I9 in a groove in the pin by a set screw having a handle 4I and locked to the casting by a set screw 36. By this construction, the boom may be supported on other mounts, such as lamp tripods, if desired. The pivot point on the hangers l5 Shown at 4S for tilting the crossarm is forward of the axis of the standard to obtain the maximum in rear overhang of the crossarm commensurate with stability.

The horizontal or crossarm portion of the boom has two main sections, an outer hollow section t2 and an inner hollow section 43. (See Fig. l1.) The outer section 42 is suspended on the pivot 46 between the two triangular hangers 45, Clamped on the section 42 is a sectional flange Ail suspended between the brackets ll, the flange 4l being adapted to be locked against the brackets l5 in any adjusted position of the crossarm by a set screw turnable by a handle 48. (See Figs. 2 and 6.) The mounting 32 and the flange @l is all one casting.

At the outer end of the telescoping crossarm member L53, is a bracket 49 which supports a hollow shaft 5! on which a pulley 5I is rotatable, the pulley housing a coiled tension spring. At tached to the pulley 5l is a microphone cradle 52 to which a microphone 5@ is attached in any suitable manner. By the use of a spring to rotate the microphone in one direction and a single cable such as 96 (see Fig. 2) having a few turns wrapped around pulley 5I with the end attached thereto to rotate the microphone in the opposite direction, the microphone 54 is readily controlled to its optimum pickup position when the source of sound shifts about the set. An electrical cable 55 having a terminal plug 33 is connected to the microphone and passes up through the hole in the shaft 5@ and is attached to a bracket 5S on the telescopic member 3.

The main supporting member 2 carries a fixed mounting bracket 5l at one end thereof and a counterweight 58 at thc other end thereof together with a handle 53 (see Fig. 5) for manually tilting and rotating the crossarm. With the counterweight 58 xed, it can be of considerable weight, which reduces the rear portion of the member l2 for a given length of boom. However, the counterweight 58 may be adjusted to provide the proper balance when microphones of different weights are attached to cradle 52. Just in front of pivotl point 46 is a bracket 59 mounted on the member 52, while a third bracket 24 is attached to member 42 on the rear side of the pivot point 46.

Between the brackets 5l and 5), two track rods 69 and 6I extend, on which a counterweight carriage 62 travels between the brackets to .counterbalance the weight of the microphone 54 and crossarm section 3 during extension and retraction. The counterweight carriage 62 is mounted on eight rollers (See Figs. 3 and 4) there being four top rollers, two of which are shown at 64 and 65 in Fig. 4 and one in Fig. 3, and four rollers at 45 degrees, two to each rod, one of which is shown at 66 on rod 56, and one at 61 on rod 6I. By mountingthe traveling counterweight 62 in this manner, av smooth noiseless motion is obtained. The counterweight carriage 62 also carries a pulley 63 for the electric cable 55 and a pulley lll for the cable 96 which controls the rotation of the microphone 54. On the bracket 59 is a pulley 'II for the electric cable 55, and a guide roller Si, whileA the bracket Il carries a bellcrank 'I2 on ,one arm of lwhich is a pulley 'I3 around which the cable for rotating the micro-- phone pas/ses. A guide roller 8S is also mounted on bracket 6U. (See Fig. 6.)

Referring again to front bracket 5l' on the member 42, this bracket not only supports the ends of the track rods `|50 and E I, but also carries a rubber tired roller on which the section 43 travels and is supported, a pulley 11, over which the microphone electrical cable -55 travels, a pulley 16, around which the control cable 9| for the counterweight carriage B2 passes, and a horizontally mounted pulley 13 around which the cable 82 passes for extending and retracting the member 43.

The manner and means for controlling the length of the crossarm by the position of the section 413 within the section 42, is shown in Figs. 5, 6, 7, and 1l. As mentioned above, the section 43 rolls on roller 15 at the end of member 42, while the inner end of the member 43 carries a roller 85 mounted Within a rectangular bearing bracket 8| attached to the end of section 43. The roller V841 rotates on a horizontal axis, and is made of rubber like roller 15, so as to provide noiseless operation when the member 43 is extended and retracted. The control cable 82 is fastened to the Y end of thebracket 8| and passes around a pulley 83 at the rear end of the section 42 and then over guide pulley y86 to take-up sheave drum I34 to which a handle 85 is attached for rotating the drum. The extension cable `8:2 continues from the drum 84 over guide pulley 81 on bracket 59 to pulley 18 where it passes inside the member 42 and between sections 42 and 43 to the bearing bracket 8| to which it is attached. Thus, it will be observed that rotation of the drum 8,4 will pull the inner section 43 in and out of the hollow section 42 extending the microphone 54 away from and retracting it toward the supporting standard.

Referring now to Fig. 9, it Will be noted that the cable y9| is attached to one end of the counterweight carriage 62, and passes around pulley 16, then around a drive pulley 92, over a pulley 93, and to the other end of carriage 62. The pulley S2 is mounted on the same shaft with drum 84, and the pulley 92 therefore rotates with the drum 84. As the drum 92 rotates, the counterweight carriage `62 is moved along the track rods 63 and 5| and thus counterbalances the microphone and rod 43 as the rotation of drum 84 extends and retracts the microphone. In this manner, the boom will always be maintained in balance, which is a necessary condition for its efcient operation.

In order to permit the microphone electrical cable 55 to be lengthened and shortened as the microphone is moved away from and toward the standard, the counterweight carriage r|52 carries the microphone electrical cable 55 over pulley 69, the cable 55 also passing around the pulley 1| on bracket 59. (See iFig. l0.) The cable is attached to the bracket 59 at 94. Thus, as the microphone end of the cable 55 moves outwardly, the pulley 69 approaches the pulley 1| along with carriage `52 and supplies the necessary length of cable.

As mentioned above, the crank 12 pivoted at 95 (see Fig. 8), rotates the bracket 52 and thus the microphone 54, since the crank bodily translates the pulley 13 in an arc toward the rear end of the crossarm, thus effectively shortening the cable 93 between the microphone and pulley 13. The cable extends from the wheel 5| over rollers 91 and 98, around crank roller 13, back around roller 13 on the counterweight carriage 62 and then to point 93 on bracket 5S Where it is attached. It will be noted that as the microphone is extended, the microphone end of the cable 9E may be extended also, since the roller 10 is brought toward the roller 13. The microphone may thus be rotated when in any extended position, since the effective shortening of cable 9B will rotate the microphone in one direction, while the release of crank 12 will rotate the microphone in the opposite direction by the tension of the spring in the pulley f5 In the past, several types of mechanism have been employed for rotating the microphone, such as geared rods rotatable by hand, but these prior structures do not provide the accuracy and noiseless control such as is obtainable with the simple lever action just described.

The above described microphone construction not only permits the use of a microphone within a small room being used as the set, but provides a complete lateral, vertical, and rotational control thereof in the same manner as the former types of boom having long overhangs. The threewheeled perambulator may be extended to transport the boom stably to the desired location, and may be then contracted, both in tread and wheel base, to pass through small openings and to occupy the minimum of space. Even though the rear counterweight is iixed to provide a short rear length of crossarm, the boom is perfectly balanced at al1 times by having a traveling counterweight on the microphone side of the crossarm. All controls are within easy reach of the operator with a minimum of movement, while the rotational v control, which is used more than the others, is arranged in its simplest and most convenient form.

We claim as our invention:

1. A boom comprising a crossarm adapted to be extended and retracted, a standard for supporting said crossarm, means for extending Said standard for elevating said crossarm, means connecting said standard and crossarm for tilting and rotating said crossarm, :a counterweight on one end of said crossarm xedly mounted thereon, a second counterweight movable along said crossarm on the other side of said standard, and means for varying the position of said second counterweight on said crossarm during the extension and retraction of said crossarm.

2. A boom having an extensible and retractable crossarm, means for pivoting said crossarm nelar one end thereof, a standard for supporting said crossarm at said pivot point, a counterweight on said crossarm on one side of said standard, said -counterweight being xed on said crossarm, and an adjustable counterweight on said crossarm on the other side of said standard, said second counterweight being adjustable along said crossarm as said crossarm is extended and retracted.

3. A microphone boom for adjustably positioning a microphone at a point within a predetermined` space comprising a standard, a iixed cross- :arm section pivoted on said standard, a second crossarm section adapted to be extended and retracted `in and out of said fixed crossarm section, a microphone mounted on the end of said extensible crossarm section, means for extending and retracting said extensible crossarm section, a counterweight mounted on s'aid xed crossarm between said standard and microphone, and means for moving said counterweight toward said standard as said microphone is moved away from said standard.

4.-. A microphone boom comprising a standard, a xed crossarm section pivotally and rotatably mounted at the top of said standard, a second crossarm section slidlable in and out of said iixed crossarm section, a microphone rotatably mounted on the end of said second crossarm section, a counterweight positioned between said standard and4 said microphone onv said xed crossarm section, means for moving said counterweight along. said xed crossarm section as said microphone is moved away and toward said standard, a lever pivoted on said fixed crossarm member adjacent said standard, and means extending from said lever to said counterweight and to said microphone rotating means for rotating said microphone when said lever is actuated.

5. A microphone boom in accordance with claim 4 in which said last mentioned means includes a pulley on said counterweight, a pulley on said lever, and a cable from said microphone and extending around said pulleys.

6. A microphone boom comprising a vertical standard, a crossarm having a section pivotally and rotatably mounted on the top of said standard, and van extensible section within said first section, a microphone rotatably mounted on the end of said extensible section, a drum on said standard, cable moans extending from said extensible section to said drum for extending and retracting said extensible section, a counterweight carriage, means for mounting said carriage between said microphone and said standard, a pulley adapted to rotate with said drum, cable means extending between said pulley and saidy carriage for moving said carriage, and cable means extending from said lever to said carriage and to said microphone for rotating said microphone when said lever is actuated.

7. A microphoneboorn comprising a vertical standard, a crossarm mounted on top` of said standard, said crossarm being adapted to be lengthened and shortened, a counterweight adjustable along said crossarm on one side of said standard, and la second counterweight fixedly mounted on said crossarm on the other side of said standard.

8. A microphone boom in accordance with claim 7 in which a microphone is attached to one end of said crossarm, said xedly mounted counterweight being lattached to the other end of said cross arm at a point to counterbalance both said microphone and adjustable counterweight.

9. A microphone boom construction comprising a mast, a bracket adapted to rotate on a vertical axis von the top of said mast, a crossarm adapted to be mounted on a horizontal axis at the upper end of said bracket, a flange adapted to move with the crossarm, means on said bracket for locking said flange thereto in any adjusted position of said crossarm, a movable carriage, means or'mounting said carriage under said crossarm, means for extending and retracting said crossarm away from and toward said mast, and means for simultaneously moving said carriage with the extension and retraction of said crossarm.

10. An extensible boom construction comprising a hollow member, a mast, means for pivoting said hollow member at the top of said mast, a second member adapted to slide in and out of said hollow member, said second member having a microphone mounted at one end thereof, a roller on the inner end of said second member for con tacting the inner surface of said hollow member, a second roller on the end of said hollow member adapted to support said second member, a plurality of track rods mounted on said hollow member, a carriage adapted to travel on said rods, cable means for moving said carriage toward said mast when said microphone is moved away from said mast, an electric cable forsaid microphone, a cable for rotating said microphone, and a plurality of pulleys on said carriage for carrying said electrical cable and said rotating cable in a taut condition during the extension and retraction of said microphone.

11. An extensible boom construction in accordance with claim 10 in which said mast comprises an upper section and a lower section, and means are provided for raising and lowering one section thereof.

12. An extensible boom construction comprising a hollow crossarm member, a second crossarm member adapted to slide in and out of said hollow member, a microphone, a hanger for mounting said microphone for rotation on the end of said second member, a track mounted on said hollow member, a carriage adapted to travel on said track as said second member is extended and retracted, a lever mounted on said hollow member, and a cable connected to said hanger and passing from said hanger to said lever and to said carriage, rotation of said lever rotating said microphone in any adjusted position.

13. An extensible boom construction in accordance with claim 12 in which an electrical cable is provided for said microphone, said electrical cable being carried by said carriage.

14. In a mechanism of the kind described, an extensible crossarm, a standard supporting said crossarm, means connecting said crossarm to said standard whereby said crossarm may be both tilted and rotated with respect to said standard, counterweights on said crossarm, means for simultaneously extending or retracting said crossarm and shifting the position of one of said weights to compensate for the out of balance condition that develops during the extension or retractionv of said crossarm, a base on which said standard is mounted, and means whereby said base may be extended both laterally and longitudinally to render said mechanism stable in any position of use.

15. A microphone boom comprising a base, means whereby said base may be expanded both laterally and longitudinally to insure stability of the boom in any extended position, a vertical standard mounted on said base, a crossarm mounted on top of said standard, said crossarm being adapted to be lengthened and shortened, a counterweight adjustable along said crossarm on one side of said standard, and a second counterweight xedly mounted on said crossarm on the other side of said standard.

BYRON F. RYAN ELMER H. SMITH.

REFERENCES Cll'llED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 2,235,518 Goshaw Mar. 18, 1941 2,122,778 Meuller July 5, 1938 2,053,833 Jones Sept. 8, 1936 2,003,162 Ulmer May 28, 1935 1,887,067 Pehrsson Nov. 8, 1932

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