(No Model.) 3 Sheets-Sheet 1. H. S. S. WAT KIN. ANEROID BAROMETER, No. 394,668, Patented Dec. 18, 1888. u D. L. E. 5. N. perers, Photo-lithographer, Washington, D.C.
No Model.) No. 394,668 3 Sheets-Sheet 3. H. S. S. WATKIN. ANEROID BAROMETER, Patented Dec. 18, 1888.??22222222222222222ZZZZZZzzzzzzz! 6 --- - - - - - - - S. N, PETERS, photo-thographer, Washingos, D.C.
UNITED STATES PATENT OFFICE. HENRY SAMUEL SPILLER WATKIN, OF THE WILDERNESS, CANTWELL ROAD, WOOLWICH, COUNTY OF KENT, ENGLAND. ANERO D BARO METER. s y SPECIFICATION forming part of Letters Patent No. 394,668, dated Dacember 18, 1888. Application filed February 27, 1888, Serial No. 265,389, (No model.) Patented in England November 13, 1886, No. 14,730, To all whon, it may concern: Be it known that I, HENRY SAMUEL SPIL LER WATKIN, of The Wilderness, Cantwell Road, Woolwich, in the county of Kent, Eng 5 land, major royal artillery, have invented certain new and useful Improvements in Ane roid Barometers, (for which I have obtained Letters Patent of the United Kingdom of Great Britain and Ireland, dated November Io following 13, 1886, and is a numbered specification. 14,730.) of which the The invention relates to that class of an eroid barometers which are provided with a large open scale, or a scale extended beyond I5 the Ordinary scale into two or more circles or Convolutions, so as to increase the distance be tween the graduations or reading-points, and in combination with which the index-hand or pointer is required to make two or more com 2O plete revolutions. In such class of instrument the volute spring Ordinarily employed to control the motion of the hand or pointer spindle is found to buckle, and therefore to act irregularly on the said 25 spindle. The first part of the invention con sists of means for remedying this defect, and the Second part relates to improvements in the indicating mechanism of such class of barometers. 3ol. In the accompanying drawings I have rep resented various modes in which my inven tion may be carried into effect. In all the figures like parts are indicated by. similar letters of reference. 35 Figure 1 is an elevation, partly in section on the line 11, Fig. 2, showing the principal working parts of the instrument and omitting the casing and dial. Fig. 2 is a front view of the same parts, partly in section on the line 4o 2 2, Fig. 1. Fig. 2 is an elevation of the in dicator portion of the mechanism shown in Fig. 2. Fig. 3 is an axial section of the entire instrument, on a smaller scale, on the line 33, Fig. 4. Fig. 4 is a face view thereof. Fig. 5 45 is an elevation of the parts shown in Fig. 1, but representing the substitution of a cylin drical coiled spring for the helical hair-spring shown in Figs. 1 and 2. Fig. 6 is a partial face view showing a modification in the dial. 5O Fig. 6 is an elevation of the indicator por tion of the mechanism shown in Fig. 6. Fig. 7 is an elevation illustrating another modifi cation in the controlling-spring. Fig. 8 is a front view of the same parts. Fig. 9 is an axial sectional elevation showing another 55 modification in the controlling-spring. Fig. 10 is a partial face View of the same parts. Fig. 11 is an axial sectional elevation illus trating a modification in the device to indi cate the scale from which the reading is to be 6o taken. Fig. 12 is a partial face view of the same parts. Fig. 13 illustrates a modification in which the dial rotates beneath a fixed in dicator. ( represents the case of the instrument; b, 65 the vacuum-chamber; c, the counteracting spring; (l, the operating-lever attached to and operated by the spring c, e, a link connect ing the lever (l to an adjustable arm, f', fixed on the rocking barf; and f', an arm or lever, 7 O also fixed to the rocking bar f, and which has its upper end connected by a chain, g, to a worm or screw, h, formed or fixed on the spindle h, carrying the reading hand Ol' pointer i. 75 The spindle h is mounted in bearings car ried by the bracket. The parts above described form no part of my present invention. In such class of instrument it is usual to 8o employ a volute spring, l, Sufficient to control the motion of the hand or pointer spindle ll to the extent of a single revolution; but such spring, when employed in combination with a hand or pointer which is required to make 85 two or more complete revolutions, is found to buckle, and therefore to act irregularly on the spindle 1. In order to remedy this defect, I, according to one arrangement, as shown at Figs. 1, 2, 3, and 11, inclose the said volute 9o spring, l, in a suitable box or case, In, which is so proportioned as to permit of the full ac tion of the sping l, and is yet so shallow as to prevent the buckling thereof when it has per formed more than a complete turn, thus en- 95 abling the controlling-spring to accomplish the additional Work required of it in connec tion with the spindle of an open-scale aneroid barometer. - In another modification, as represented at Ioo Figs, 5 and 6, I substitute for the ordinary volute spring,l, a cylindrical coiled spring, l,
g 394,668 Surrounding the index-hand or pointer spin dile h, and of sufficient length to enable it to make the required number of revolutions, and yet to act efficiently on the spindle hi. 5 According to another arrangement, as rep resented at Figs. 7 and 8, I fix one end of a cylindrical coiled spring, l', to a fixed stud, in, While the other end is connected to a thread Or ligature, l', passed several times round a Io spiral groove or screw-thread, h, formed on the spindle h, and such thread or ligature l' is fixed to the spindle h beyond such spiral groove or screw-thread h, which latter is formed in the opposite direction to that of I5 the screw-thread or worm h, around which the chain or other connection g, actuating the Spindle h in one direction, is coiled. The spring li may occupy the position shown by either the full lines or the dotted lines in 2O Fig. 8. In still another modification, as represented at Figs. 9 and 10, I employ a volute spring, l, of the Ordinary form; but I fix it to and around a separate spindle, o, which has a 25 toothed wheel, O'', fixed thereon, which works into a toothed pinion, h, fixed on the hand or pointer spindleh, whereby any required num ber of revolutions may be given to the latter and a smaller number to the spring-spindle 3O O, thereby securing the correct action of the spring lupon the hand or pointer spindle h. I Would here remark that the improvements above described are equally applicable to an eroid barometers of the character described 35 in the specification of Letters Patent granted to me June 14, 1887, No. 364,692. In carrying out the second part of my in Vention I in some cases employ a dial, k, with two Or more Concentric circles of Scales en 4o graved thereon, as represented at Figs. 2, 4, 6, 10, and 12, and in combination there with I employ a hand or pointer, i, sufficiently long to extend across all of such concentric cir Cles, and according to one arrangement, as 45 shown at Fig. 4, I form such hand i with as many finger's or pointers as there are cir cles of Scales, each of such pointers i' point ing to a separate circle; and in order to indi cate Which circle of scales should be looked 5o at I employ, according to the arrangement shown at Fig. 2, an indicator, p, connected to or operated by the rocking barf and chain g, giving motion to the hand or pointer spindle h in such manner as to cause such indicator 55 p to point to the circle of divisions and fig ures to be looked at, the diameter or trace of the circle being made to correspond to the movement of the pointer p for each complete. turn of the index-fingeri; or, according to the 6o arrangement represented at Fig. 6, I cause such indicator hand or pointer p to point to One or other of a series of figures, 1 2 3, en graved. On the dial-plate k, to indicate which Scale or circle of divisions and figures is to be 65 looked at; or I form such indicator p, as rep resented at Figs. 3, 4, 9, and 10, with a series of figures engraved on a plate, p", carried by a link, p, one end of which is connected to the upper end of the arm f and the other to the chain g, Thus either of the figures will be exhibited through an aperture, k', in the dial le, according to which circle of divisions and figures is to be observed; or the movement of the rocking barf and chain g may, as rep resented at Figs. 11 and 12, cause the revo lution of an indicator or finger, p, on a small circle, k, on the dial-plate le. This circle k' is engraved with figures denoting which cir cle of graduations is to be read under the in dex-needle i. In carrying this arrangement into effect the indicator p is mounted on an axis, p, which has fixed thereon a screw thread, p", around which the chain g passes in its way from the arm f to the spindle h. In the various arrangements represented at Figs. 2, 4, 6, 10, and 12 the dial-plate k has arrowski engraved thereon between the sev eral circles of scales, in order to indicate the points where the reading of one circle ends and another begins. The hand or pointer may, if desired, extend only to the inner cir cular scale, in which case I employ a movable pointer, q, connected to a movable ring, r, On the case, and extending across all the Scales and nearly meeting the hand or pointer i, so that any scale can be read off by placing the said movable pointer in line with the hand or pointer i, as shown by the dotted lines in Fig. 4. The breaks in the concentric scales or cir cles represented in Eigs. 2, 4, 6, 10, and 12 readily show the points at which the reading is to be transferred from one scale to the next, and the figures arranged in either of the vari ous modes described indicate at once to the observer which scale is to be read to show the correct indication. Having thus described my invention, the following is what I claim as new therein and desire to secure by Letters Patent: 1. An aneroid barometer having a large open Scale and a hand or pointer adapted to make more than one revolution, and a con trolling-spring guided or controlled to prevent buckling, substantially as herein described. 2. An aneroid barometer having a hand or lution, and a dial with two or more concentric scales on which the indications of the hand or pointer are successively read, the gradua tions on the outer scales forming a continua tion of the inner scale, substantially as set forth. 3. An aneroid barometer having a reading hand or pointer adapted to make more than One revolution, several concentric scales on which the indications are to be successively read, and a hand or pointer for indicating which scale is to be observed, substantially as described. 4. An aneroid barometer constructed with a large open scale, a spindle having a hand or pointer adapted to make more than one 75 90 95 O II5 I25 13o
revolution, a volute spring, and a box or case controlling the spring, substantially as de scribed. 5. An aneroid barometer constructed with a 5 large open scale and a spindlehaving a hand or lution, provided with two or more fingers, i, for different parts of the scale, substantially as described. Io 6. An aneroid barometer constructed with an open Scale, a spindle having a hand or lution, a rock-bar having an arm, a chain con necting the arm to the Spindle, and an indi 15 cator operated by the spindle and arm, sub stantially as described. 394,668 7. An aneroid barometer constructed with an open scale, a spindle having a hand or lution, a rock-bar having an arm, a chain con- 20 necting the arm to the spindle, a slotted dial, and an indicator, p, working in the slot of the dial, substantially as described. HENRY SAMUEL SPILLER WATKIN. Witnesses: G. D.A. ALEXANDER, Capt. R. A. M. TAYLOR, Lt. R. A. 3