US2134847A - Searchlight - Google Patents

Description

'Nov. 1, 1938. 1. A. YOST ET AL SEARCHLIGHT Filed Oct. 50, 1955 3 Sheets-Sheet l Nov. 1, 1938. A. YosT ET AL SEARCHLIGHT Filed 001;. 30, 1935 5 Sheets-Sheet 2 lNVEHTC-RS WITNESSES: W/Xm n.

M/K/arrz fiicaizj Nov. 1, 1938.

l. A. YOST ET AL SEARCHLIGHT Filed Oct. 50, 1935 5 Sheets-Sheet 3 Patented Nov. 1, 1938 UNITED STATES PATENT OFFlCE Jacobi, Wilkinsburg,

Pa., assignors to Westinghouse Electric & Manufacturing Company,

East Pittsburgh, Pa.,

sylvania a corporation of Penn- Applicaticn October 30, 1935, Serial No. 47,446

10 Claims.

The invention relates, generally, to searchlights, and, more particularly, to the construction of arc searchlights as regards the supporting of the arc head mechanism or unit and the operating mechanism therefor.

Heretofore, it has been the usual practice to support the arc head mechanism, comprising the electrode holders, feed rollers, etc., within the drum in the proper relation to the reflector by means of a suitable standard or column secured to the bottom of the drum. Such forms of support perform no useful function other than to support the arc head unit and are not sufliciently rigid and stable to maintain the arc head unit in the same position with respect to the reflector for all possible positions of the searchlight drum and under all operating conditions.

In addition, searchlights of large diameter have been usually designed with a glass front made up of a plurality of segments of glass supported and retained in the desired relationship by means of a suitable center piece and a plurality of brackets vertically disposed diametrically across the drum, leaving the joints formed by the abutting edges of the glass segments exposed to the direct light rays of the beam producing light dispersion and thus a source of stray light.

It is, therefore, one of the primary purposes and objects of the present invention to provide for the elimination of the aforementioned defects and disadvantages by utilizing a form of support for the arc head mechanism which will rigidly support it in fixed relation to the reflector under all operating conditions and which will function to eliminate light dispersion produced by the joints in the glass front.

A more specific object of the invention is to provide for supporting the arc head unit or mechanism by means of radially disposed brackets or strips secured to the side walls of the drum in spaced relation and for utilizing the brackets both as conductors to carry current to the arc and as screens to block off the light from the joints between the glass segments of the front cover.

Another object of the invention is to provide for utilizing the supporting means for the arc head unit or mechanism for conducting current to the arc head or the operating mechanism therefor, or both, as the case may be.

A still further object of the invention is to provide for utilizing the trunnion support of the drum as a compartment to house the operating mechanism for the arc head, thus providing a closed compartment without the use of a separate control casing or box attached to the outside of the drum.

Another object of the invention is to provide for utilizing the radial brackets of the support for the arc head unit or mechanism in conjunction with the radial brackets of the front door or cover for the drum for the purpose of effectively screening the radially disposed joints between the glass segments of the door from the light produced by the arc to eliminate stray light.

The general object of the invention is to provide a searchlight structure which shall be simple and efficient in operation and which may be readily manufactured, assembled and maintained.

These and other important objects and advantages of the invention will become more apparent from a reading of the following detailed description taken in conjunction with the drawings wherein,

Figure l is a front elevational view of a searchlight, with the front door or cover removed, embodying the principal features of the invention,

Fig. 2. is a side elevational view partially in section taken along lines IIII of the structure of Fig. 1

Fig. 3 is a front elevational view of the front cover or door for the searchlight structure of Figs. 1 and 2,

Fig. 4 is a view taken along lines IV-IV of Fig. 3

Fig. 5 is an enlarged top plan View, partially in section, of the Searchlight showing the manner in which the operating mechanism is mounted within the trunnion support, and

Fig. 6 is an enlarged side elevational view in cross section of the trunnion assembly of Fig. 5.

In the preferred embodiment of the invention, the arc head unit or mechanism comprising the electrode holders, feed rollers, etc., is supported for movement along the longitudinal axis of the drum by means of a supporting ring or bracket and a plurality of radial members interposed between the supporting bracket and the side walls of the drum. The radial members may be equally spaced and positioned directly opposite or behind certain ones of the joints between the glass segments of the front door in such manner that they cooperate with the radial supports of the door to effectively screen all of the door joints from the light produced by the arc, the radial supports for the door preferably alternating in position with the radial support members of the arc head support.

The mechanism for operating the arc head is mounted'within one of the hollow trunnion supports and connected to the arc head mechanism body regardless of the drum position and does by means of suitable drive shafts and universal joints.

Certain ones of the radial members of the arc head support are utilized as current conductors to carry current to the electrodes or the operating mechanism, or both, as the case may be, thus eliminating the use of separate conductors in the drum to complete the arc circuit.

Referring now to the drawings, there is shown in Figs. 1, 2 and 5 a searchlight drum 8, rotatably mounted for movement about a horizontal axis on trunnion assemblies 9 and H3, in which the arc head unit H and operating mechanism |2 therefor are mounted in accordance with the principles of the invention.

It is to be understood that since the details of construction of the arc head unit I I and operating mechanism |2 do not in themselves constitute part of the present invention, these elements have been illustrated in a more or less diagrammatic manner to illustrate the invention without unduly complicating the drawings. By way of example, the arc head unit may be of the type that both rotates and feeds the positive electrode E3 and which is actuated by the operating mechanism l2 by means of a detachable shaft connection M in a well known manner. The feed rollers l5 for controlling the movements of the negative electrode I6 may likewise be driven through a similar shaft connection I! by the operating mechanism l2.

In order to provide for supporting the arc head unit it within the drum in the proper relation to the reflector l8 and in a rigid manner by means which will eliminate stray light and perform other useful functions as well, there is utilized an arrangement comprising a supporting bracket or ring L! and a plurality of radial members 2i to 26, inclusive.

As will be observed, the arc head unit II in this instance is movably supported within the supporting ring l9 by means of a plurality of slide rails or bars 21 through 30, which cooperate with suitable guide ways 3| formed on the inside of the ring I9. This permits the arc head to be adjusted along the longitudinal axis of the drum and enables it to be readily removed for inspection and repair. The movements of the arc head may be effected in any suitable manner such as by the actuating rod or shaft 32 and gears 33. The adjusting rod 32 may be operated in any suitable or desired manner from without the drum in order that adjustments of the arc head may be made while the light is in operation.

The radial members 2| through 26 are of relatively thin flat shape having their narrow edges exposed to the light source in order to interfere as little as possible with the projected light. They are suitably secured at their outer ends to the rim portion 34 of the drum and are secured to the support ring |9 at their inner ends. As shown in Fig. 2, the radial members are projected or inclined outwardly in order that the supporting structure will not sag as the drum I is rotated about its horizontal axis.

As shown in Fig. 2, the rim portion 34 of the drum 8 is preferably formed integrally with the side Walls thereof and extends inwardly in the form of a flange. It provides an enlarged rim portion of such size as to reinforce the front opening of the drum in such a way as to strengthen and increase the rigidity thereof.

It apparent that this construction is of such nature as to distribute the load to the rigid drum not subject the drum structure to a concentrated strain at only one position.

The front door or cover 35 for the drum 8 is shown in Figs. 3 and 4 and comprises gener ally a rim element 38 which may be hingedly secured to the drum by means of suitable hinge lugs 3'! which are disposed to cooperate with the hinge lugs 38 on the drum. Clamping devices 39 are provided on the drum for securing the door in a closed position.

In this instance, the door is made up of a plurality of glass segments 4| which are clamped to the rim 36 by plates 42 and which are supported by means of a center piece 43 secured to the rim 36 by means of radial members 46. In this instance, the glass portion of the door is made up of twelve segments forming an equal number of radial joints 4'| therebetween.

It has been observed that the joints 41 between the glass segments 4| of the door produce light dispersion which is the cause of a considerable amount of stray light. In order to provide for reducing the stray light thus produced without the use of separate means for this purpose only, provision is made for utilizing the radial members of both the door and the arc head supporting structure to effectively screen every joint from the projected light.

In this instance, since there are twelve joints to be protected, thus requiring a total of twelve screening devices, six radial members are utilized in both the door and the arc head support, the radial members 46 of the door alternating in position with those of the arc head support. It is apparent that the radial members 45 in the door structure are fixed in position directly opposite or behind alternate joints between the glass segments and that the radial members of the arc head support are so positioned that when the door 35 is secured to the drum and in its closed position, they likewise are positioned directly behind the remaining joints. Since all of the radial members are of thin construction, the total area thereof which is exposed to the projected light is so small as to be of no consequence. At the same time, these members are of suflicient thickness to effectively screen the joints from the projected light.

With a View to providing a housing for the operating mechanism I2 for the arc head without utilizing a separate control box or housing secured to the outside of the drum as is the usual custom, provision is made in this instance for utilizing one of the trunnion assemblies for this purpose.

In this instance, the operating mechanism l2 which may be of any suitable design is mounted within the trunnion assembly 9. Referring to Figs. and 6, it will be observed that the trunnion assembly 9 is so constructed that it forms a compartment on the side of the drum. The trunnion member 5| in this instance is integral with a dome-shaped support member 52 which is suitably secured to the side of the drum. The trunnion 5| is supported by means of a suitable bearing 53 which is carried in the trunnion housing 54 which, as shown in Fig. 1, is adapted to be bolted or otherwise secured to one of the arms 55 of the trunnion cradle. A suitable opening 56 is provided in the drum opposite the trunnion which may be covered by a plate 51 in order to enclose the compartment thus formed. If desired, the operating mechanism may be mounted upon the plate 57 in order to facilitate in its removal from the compartment. As shown, the trunnion is in the nature of a hollow shaft through which any additional control devices may be passed, if desired. The trunnion assembly l0 may be of the same construction as the trunnion assembly 9 and may be utilized to house other control devices.

In order to provide for carrying current to the arc head H and the operating mechanism l2 therefor, provision is made for utilizing certain ones of the radial members of the arc head support for this purpose. In this instance, it is assumed that the arc current also passes through the operating mechanism l2 and a circuit for accomplishing this purpose is illustrated. As shown, the radial members 2|, 23, 24 and 26 are insulated by means of suitable insulating members 66 from the rim 34 and the supporting ring IS. The current supply conductors while not shown may be brought in through the arm 58 of the trunnion cradle and connected to the terminals 59 and 6!, as shown. The internal circuit for the drum may then be formed by connecting the supply terminals 59 and 6| to the radial members 2| and 26 by suitable shunts 62 and 63, by connecting the radials 2| and 23 with a shunt 64 and by connecting each of the radials 23 and 24 to the terminals 65 and 66 by means of shunts 6i and 68. As shown in Fig. 2, the circuit is then completed through the are by connecting the radial member 24 to the positive electrode holder by means of a suitable shunt t9 and the radial member 26 to the negative electrode holder by means of a shunt TI. The terminals 65 and 63 are mounted upon the plate 51 which encloses the trunnion compartment and suitable connections provided therefrom to those elements of the operating mechanism which are to be subjected to the arc current.

It is to be understood that in case it is desired to conduct current to the are only, radial members 2! and 26 may be used for this purpose.

In view of the foregoing description, it is apparent that the invention embodies features and principles which are novel and of great utility in connection with the construction of high intensity arc searchlights where the greatest efliciency obtainable is desired. The nature of the arc head supporting structure makes possible its use for the performance of several functions thereby simplifying the construction to a considerable degree. Its use as a supporting means which is its primary function provides for rigidly supporting the arc head mechanism. Its auxiliary function in conjunction with the radial members of the door to eliminate stray light makes it unnecessary to provide separate means for effecting this function. Its additional auxiliary function as a current conductor for the are or the operating mechanism, or both eliminates the necessity for placing separate current conductors within the drum.

Although a specific embodiment of the invention has been illustrated and described, it will be obvious to those skilled in the art that various changes may be made in the details of construc tion such as in the proportion and the design of the several cooperating parts without departing from the principles herein set forth.

We claim as our invention:

1. A searchlight comprising a drum, a transparent cover therefor comprising a plurality of segments of transparent material, an arc head mechanism, and a plurality of radially disposed members for supporting the arc head mechanism from the sides of the drum, said radially disposed members being positioned directly opposite the joints between the transparent segments of the cover.

2. A searchlight comprising a drum, a transparent cover therefor comprising a plurality of segments of transparent material, and means comprising a plurality of radially disposed supporting members for supporting the arc-head mechanism from the walls of the drum, said supporting members being positioned adjacent to every other one of the joints between the segments between the transparent cover and the arc head mechanism thereby to cast a shadow upon the joints and eliminate light dispersion.

3. A searchlight comprising a drum, a door for the drum comprising a plurality of glass segments and radially disposed support members positioned adjacent a plurality of the joints between the segments, an arc head mechanism,and means including a plurality of radially disposed members for supporting the arc head from the walls of the drum, said last-named radial supports being positioned adjacent the remainder of the joints between the glass segments.

4. A searchlight comprising a drum, a door for the drum comprising a plurality of glass segments and radially disposed support members positioned adjacent a plurality of the joints between. the segments, an arc head mechanism, a bracket member for movably supporting the arc head mechanism, a plurality of radial members for supporting the bracket member from the sides of the drum, said radial members being interposed between the radial support members for the door and adjacent the joints between the glass segments.

5. A searchlight comprising a drum having an integral back portion and a reinforcing ring portion around the edge of the front opening, an arc head mechanism, a supporting bracket for the arc head mechanism, and a plurality of substantially equally spaced fiat shaped radial members interposed between the supporting bracket and the reinforcing ring portion of the drum for supporting the arc head mechanism.

6. A searchlight comprising a drum, supporting trunnions on opposite sides of the drum, an arc head mechanism, means including a plurality of radially disposed current conducting members of fiat shape for supporting the arc head mechanism from the side walls of the drum, power supply terminals positioned within the drum adjacent one of said supporting trunnions, and means including at least two of said radial supporting members for connecting the power supply terminals to the arc head mechanism.

'7. A searchlight comprising a drum, supporting trunnions on opposite sides of the drum, an arc head mechanism, means including a plurality of radially disposed current conducting members of fiat shape for supporting the arc head mechanism from the side walls of the drum, power supply terminals mounted within the drum adjacent one of said supporting trunnions and movable therewith, means for connecting the outer ends of two of said radial supporting members to the power supply terminals, and means connecting the opposite ends of said radial supporting members to the arc mechanism to provide for supplying current thereto.

8. A searchlight comprising a drum, an arc mechanism, electrically-operated means for actuating the arc mechanism, terminal members for said electrically operated means extending within the drum, power supply terminals mounted within the drum, means including a plurality of radially-disposed members for supporting the arc mechanism from the side walls of the drum, means for connecting the outer ends of one pair of said supporting members to the power supply terminals, means for connecting the outer ends of another pair of said supporting members to the terminal members of the electrically-operated means, means for connecting the inner ends of one supporting member in each pair together to form a continuous conductor, and means for connecting the inner ends of the other radial members of each pair to the arc mechanism.

9. A searchlight comprising a drum, a transparent cover therefor having a plurality of radial joints therein, an arc head mechanism, means including a plurality of radially disposed members for supporting the arc head mechanism from the side walls of the drum, said supporting members being located within the drum and directly behind the radial joints in the cover, power supply terminals within the drum, and means including at least two of said radial supporting members for connecting the power supply terminals to the arc head mechanism.

10. A searchlight comprising a drum, an arc head mechanism comprising a pair of electrode holders, means including a plurality of relatively thin radial members for supporting the arc head mechanism from the walls of the drum, a plurality of power supply terminals within the drum, a plurality of power consumption terminals within the drum, means for connecting the outer ends of two pairs of adjacent radial members to the power consumption and power supply terminals respectively, means for connecting the inner ends of the radial member in each pair together, and flexible means for connecting the inner ends of the other radial members in each pair to the electrode holders.

IRVINE A. YOST. WILLIAM H. JACOBI.

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