US503164A

US503164A - Mariner s compass

Info

Publication number: US503164A
Authority: US
Publication date: 1893-08-15
Anticipated expiration: 1910-08-15

Description

UNITED STATES PATENT FFICE.

EDWARD SAMUEL RITCHIE, OF NEWTON, MASSACHUSETTS.

MARI N ERS COM PASS.

SPECIFICATION forming part of Letters Patent No. 503,164, dated August 15, 1893.

Application filed January 16, 1893. Serial No. 458,476. (No model.)

. noted, and that the force required may be apev plied and transmitted to the inside of the compass bowl without causing any of the inclosed liquid to escape, or the admission of any bubbles of air within the bowl; which Iv attain by the mechanism described in the specification and represented in the accompanying drawings of which-h Y Figure 1 is a bottom View ofv the compass bowl, the cover being removed. Fig. 2 is a vertical transverse'section. Fig. 3 is a top View of a section on the line x on Fig. 2.

Similar letters refer to similar parts in the several views.

In the drawings A, denotes the compass bowl of brass or other suitable metal; B, the top ring; C, a glass cover; D, movable cover below the bowl; E, the compass card bearing the usual cardinal divisions, magnetic needle, and central cap to rest upon the supporting pivot a, which is attached to the bar b, extending across the bowl.

The bottom c, of the bowl A, has a hole, or an opening, covering which is a thin flexible metal plate d, having its outer edge raised so that it can be soldered firmly to the bottom plate c, of the bowl. The middleportion of the' plate d, is thus separated from, and is parallel with the bottom plate o, so that its central portion can be raised, or be depressed through its elasticity, without coming in contact with the plate c. The lever or arm e, has one end attached to the bowl A. Its opposite end is turned up to come in contact with the lever t', which is attached by a hinge m, to the bowl A. The lever t', extends past the center of the bowl, and has an open slit, allowing its free 5o motion over the pivot a. A projection n, be-

low the lever e, extends through the opening in the bottom of the bowl, and comes in contact with the flexible plate d. The lever or arm o, is attached by a screw, or byahinge below the bottom of the bowl A. It is bent, and extends up on the outside of the bowl, and is again bent at right angles. Aprojection r, on the lever o, comes in contact with the iiexible plate d. The lever S is connected with the bowl A. by a hinge u. The portion surrounding the pin of the hinge u, is formed as a cam, on which rests the outer end of the lever o.

In operation, by depressing the lever S, its cam raises the lever o, which raises the center of the liexible plate d, and the interior lever e, which presses up the lever t', bringing it into contact with the card E, raising it, and pressing it against the glass cover C, the card E, will thus be held in position until it is released by the raising of the lever S. To the bottom of the bowl is attached an expansion chamber w, of thin metal, to compensate for the change in volume'of the liquid with which the bowl is filled, by change in temperature. This is of usual construction.

It is evident-that any mechanical equivalent to the levers o, and S, may be used to produce the external pressure on the plate d. I am aware that a lever has been employed to raise the card from the pivot in dry compasses; and also in liquid compasses, moved by a sliding rod or screw. The objection to such has been the leakage of air, or liquid, around the sliding rod or screw.

It is evident that the projection, n, on the lever, e, and the projection, fr, on the lever, o, may be made of one rod passing through the plate, d, and fastened to it air tight, so that it can be used in place of the separate rods n,

and r. In practice I prefer to make it in this manner.. e

What I claim as my invention, and desire to secure by Letters Patent, is-

1. The combination in a compass of the card E, the lever z', the lever e, the flexible plate d, and the lever o, substantially as described.

2. The combination in a compass of the card E, the pivot, a, the lever, i, the flexible plate, d, and the lever, 0 and connections between the levers o and c', substantially as set forth.

IOO

3. The combination in a compass of the bowl A, the flexible plate, d, andthe expanbowl l?, the pivot a, the card E, the flexible sive chamber, w, substantially as set forth. plate c the lever o, with connections for trausy 1 l Y mittng external pressure to the card E, and EDWARD SAMUEL Rm CHIE 5 the expansive chamber w, substantially as set Witnesses:

forth. A. M. RITCI-IIE,

4. -The combination in a compass of the R. C. WHITFORD.