US393610A

US393610A - Pressure-gage

Info

Publication number: US393610A
Authority: US
Publication date: 1888-11-27
Anticipated expiration: 1905-11-27

Description

I (No Model.)

0. B. BOSWORTH.

PRESSURE GAGE.

No. 393,610. Patented Nov. 27, 1888...

. Ina/e 2 0750 2* Witnessem a raw (f UNITE STATES PATENT OFFICE.

CHARLES B. BOSWORTH, OF EVERETT, ASSIGNOR TO THE CROSBY STEAM GAGE AND VALVE COMPANY, OFBOSTON, MASSACHUSETTS.

PRESSURE-GAGE.

SBPEC'IPICATION forming part of Letters Patent No. 393,610, dated November 27, 1888.

Application filed July 31, 1888. Serial No. 281,536. (No model.)

To aZZ whom, it may concern.-

Be it known that I, CHARLES B. BOSWORTH,

a citizen of the United States, residing at- Everett, in the county of Middlesex and State of Massachusetts, have invented certain new and useful Improvements in Pressure-Gages; and Ido declare the following to bea full,clear, and exact description of the invention, such as will enable others skilled in the art to which to it appertains to make and use the same, reference being had to' the accompanying drawings, and to the letters and figures of reference marked thereon, which form a part of this specification. Figure 1 is a front view of a pressure-gage having my improvement applied to it, the dial being removed from the case and the lower prong of the forked link being shown as provided with a slot to receive the pin or screw in the end of the shorter branch of the Bourdon tube. Fig. 2 is a view of the forked link, showing the slot as formed in the upper prong thereof to receive the pin or screw in the end of the longer branch of the Bourdon tube. The nature of my invention is defined in the claim hereinafter presented.

In the manufacture of pressure gages in which the Bourdon tube, formed in two branches, is used to give movement to the index, and the ends of said branches are connected or pivoted to the ends of the fork of a forked link, considerable annoyance and difficulty often occurs in fitting up the gage, on account of the variation in distance apart of the ends of the said branches of the Bourdon tube, to obviate which it necessitates the bending of the prongs of the-fork more or less, to cause the holes in the ends of said prongs to coincide with those in the ends of the branches, in order to receive screws or pivots toconnect the said prongs to the said branches. Moreover, when two Bourdon tubes are thus used there arises an inequality of movement, owing to difference in the elasticity of them from variation in thickness of the metal or from being formed on curves of different radii, or from some inexplicable cause, and when their ends are connected to the prongs of the forked link, as heretofore, they are to some extent hampered-that is, the said ends of the branches do not have the freedom of movement, each independent of the other, that they do have when one of the prongs of the forked link is provided with my improvement, as hereinafter described. 5

The object of my improvement is to overcome this difficulty, which I accomplish by providing the end of one prong of the fork with a slot, a, which may be open at one end of it, or it may be closed at both ends. direction of said slot may be vertical or it may be slightly inclined, the top of the slot when inclined being in a direction away from the tube branch to which the prong of the forked link provided with the slot-is connected.

In the drawings, A denotes the case of the gage; B and O, the branches of the Bourdon tube which spring from the head D, secured to the case and formed to communicate with a steam or exhaust pipe in the usual manner.

E is the forked link, it having three arms,

a b c, as shown, the two shorter ones, a I), being connected to the ends of the branches B C by screws 11 e. The arm I) (see Fig. 2) is provided 7 5 with a slot, a, open at one end of it and slightly inclined, as represented. The slot, instead of being open as shown, may be closed at both its ends, and, if preferred, may be made in the arm a, instead of b. (See Fig. 1.) The longer arm, 0, of the forked link is connected with the toothed sectoral lever E by a connection-rod, G, pivoted to each, as shown.

The sectoral lever and the arbor H of the index are supported in a frame, I, secured to the case, and the teeth of the said sectoral lever connect with the teeth of the pinion on the arbor H of the index in the usual way.

By providing one of the prongs of the forked link with the slot, as described, the end of each 0 branch of the Bourdon tube will be free in its movements and consequently will be more sensitive to pressure and will admit of nicer adjustment of the instrument, and the difficulty of adjusting the prongs of the forked link 5 to properly connect them to the branches is effectually obviated.

I am aware of United States Patents Nos. 145,726 and 272,860, this invention being an improvement upon the device shown in the I00 The 60 latter patent. In No. 272,860 is shown a rigid forked link. As thus constructed, its connection is made with great difficulty, and usually it is necessary to bend the fork. \Vith my in vention the fastening can be readily and easily made. In No. 145,726 is shown a jointed forked link, which I desire not to use, as the rigid one is preferable. lhe means of adjustably connecting the jointed link cannot be used for the rigid link, as these means require that the arms of the fork should be movable.

Having described my improvement, what I claim is In a pressure or vacuum gage of the kind shown and described, the rigid forked link having in one of the prongs of its fork a slot CHARLES B. 3OS\VORTII.

Witnesses:

S. N. Pirnn, WM. If. ilnlcs'rtm.