US364629A - Tripod-top for photographic cameras - Google Patents

Description

(No Model.)

T. H. BLAIR.

TRIPOD TOP FOR PHOTOGRAPHIO CAMERAS.

No. 364,629. Patented June 14,1887.

UNITED. STATES PATENT OF ICE.

THOMAS H. BLAIR, or 'nosron, MASSACHUSETTS.

TRIPOD-TOP FOR PHOTOGRAPHIC CAMERAS.

SPECIFICATION forming part of Letters Patent No. 364,629, dated .l'unc 14, 1887.

Application filed January 22,1887. Serial No. 225,146. (No model.) v

To all whom it may concern:

Be it known that I, THOMAS H. BLAIR, a citizen of the United States, residing at Boston, in the county of Suffolk and State of Massachusetts, have invented certain new and useful Improvements in Tripod-Tops for'Photographic Cameras; and I do hereby declare the following to be a full, clear, and exact descrip- 'of the legs of the tripod-top-ontwardlyor away from the bolt 'by which the camera-box is secured.

Figure 1 of the drawings represents a perspective view; Fig. 2, a horizontal central section. Fig. 3 is an elevation with the tripod complete and set up.

Hitherto, in the manufacture and construction of tripod-tops for photographic cameras, they have been made triangular in general shape, while thelegs of the tripod have all been disposed at the same fixed distance from the center of said tripod. The latter is at this point provided with a bolt orpin upon which the camera-box secured thereto is pivoted.

It is evident that when the camera box is mounted upon, its tripod, and with the bellows. extended for focusing purposes, there is no support beneath and in the rear for this now projecting part of the camera-box. The latter now tends to tip back, and-in outdoor work vibrations and unsteadiness of the camera-box are increased.

My invention has for its object such a change in the construction and shape of the tripodtop that the rear portion of the camera-box, whether the bellows are extended or not, shall be furnished with a firm and stable support; andhenceIhave made oneof the tripod-legs ad justable upon the tripod-top; consequently, by

moving the pivotal point of attachment of such leg outwardly upon the tripod-top, the size of the latter is practicallyincreased and stability of the entire apparatus produced.

To this end I have shown at A a tripod-top out preferably from wood of any desired thickness, which is formed of a rectangular portion or arm, B, provided with two very much shorter but similarly-shaped arms, 0 D. These parts are so arranged with respect to each other that their central longitudinal axes emabetter balanced, and consequently there is less liability to vibrate. The bolthole a, to 0011- tain the bolt whereby the camerabox is secured to theiripod, is placed in the top A, coincident with the center of a circle which would circumscribe the arms '0 D, while the legs are to be removabl y secured to the tripodtop in the holes 1 1, 2 2, 3 3, 4 4, straddling the arms to which they are attached; hence when the apparatus is in position for work,with the bellows extended and the plate-holder in position, all the weight is along the longitudinal axis of the arm B, which is firmly upheld by the tripod-leg securedthereto by the holes 44. A series of holes, 4 4, may be disposed as shown, and thus the position of the leg attached to it may be changed to suit circumstances at any point along the arm B. Furthermore, I have provided the holes 3 3,which thus enable me .to arrange all the tripod-legs at equal distances from the bolt-hole a, after the usual manner of disposing them,while the arm B, by its superior length, still affords additional security to the rear and extensible part of the camera-box'and renders it much more steady,since the strain through the bolt-' hole a is very much diminished.

The changes in the positions of the leg c0- operating with the long arm B are suflicient to enable the operator to use the same tripod for varying sizes of camera-boxes. Thus for a small size the legs may be secured as usual; but in the event of a large box with a longfocused lens being employed, the leg, now securedsay at 3 3-is shifted outwardly to the holes 4 4 or 4 4, as may be desired; hence it is evident that this tripod combines all the good points of the ordinary tripod, with the increased advantages that for outdoor work in windy weather, or at any desired moment when increased steadiness is wanted, it can easily and readily be obtained.

I am aware that it is not new to provide a tripod-top with three devices for attaching the legs, the relative positions of these devices corresponding to those of the three arms of my tripod-top. This construction I do not claim; but

I claim 1. In a tripod, the combination, with the tripod-legs removably attached to the tripodtop, of a tripod-top formed with two short arms, 0 D, and a long arm, B, the rear tripod leg cooperating with the latter, being adjustable toward or away from the central bolt-hole,

a, substantially as and for the purposes herein stated.

2. The combination, with a tripod-top to which are removably secured tripod-legs, of a leg adjustable toward or away from the bolt which secures the camera-box,substantially as described.

3. A tripod-top, A, formed of the arms B C D, provided with the bolt-hole a, and laterally

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