Appeals from the Circuit Court of the United States for the District of Massachusetts.

Thos. Wm. Clarke and B. F. Butler, for appellants. B. F. Thurston and J. H. Millett, for appellees.

BLATCHFORD, J. On the twenty-seventh of May, 1879, the Consolidated Safety-valve Company, a Connecticut corporation, brought a suit in equity, in the circuit court of the United States for the district of Massachusetts, against the Crosby Steam Gage & Valve Company, a Massachusetts corporation, for the infringement of letters patent No. 58,294, granted to George W. Richardson, September 25, 1866, for an improvement in steam safety-valves. The specification of the patent is as follows:

"Be it known that I, George W. Richardson, of the city of Troy, in the

county of Rensselaer, in the state of New York, have invented a new and useful improvement on a safety-valve for steam generators, and I do hereby declare that the following is a full, clear, and exact description of the construction and operation of the same, reference being had to the annexed drawings, making a part of this specification, in which Fig. 1 is an end view of my improved safety-valve and its seat, as seen from the bottom; Fig. 2 is an end view of the valve alone, as seen from the bottom; Fig. 3 is a vertical section at x, x, Fig. 1, of the valve and seat in position; Fig. 4 is a vertical section at y, y, Fig. 2, of the valve alone. Similar colors and letters at reference indicate corresponding parts in the several figures A, A, is the head of the safety-valve; B, B, B, B, are wings to guide the valve into its sat, E, E; c, c, is a circular or annular flange or lip, extending over. slightly below, and fitting loosely around, the outer edge of the valve-seat, F, E; D, D, is a circular or annular chamber,

Into which the steam immediately passes when the valve lifts from its seat at the ground joint, F, F; E, E, is the valve-seat; F, F, is the ground joint of the valve and seat; P is the countersink or center upon which the point of the stud extending from the scale lever rests, in the usual manner. The nature of my invention consists in increasing the area of the head of the common safety-valve outside of its ground joint, and terminating it in such a way as to form an increased resisting surface, against which the steam escaping from the generator shall act with additional force after it has lifted the valve from its seat at the ground joint, and so, by overcoming the rapidly increasing resistance of the spring or scales, insure the lifting of the valve still higher, thus affording so certain and free a passage for the steam to escape as effectually to prevent the bursting of the boiler or generator, even when the steam is shut off and the damper left open.

"To enable others skilled in the art to make and use my invention, I will proceed to describe its construction and operation. To the head of the common safety-valve, indicated by all that portion of Fig. 2 lying within the second circle from the common center, I add what is indicated by all that portion lying outside of the said circle, in about the proportion shown in the figure. A transverse vertical section of this added portion is indicated, in Fig. 4, by those portions of the figure lying outside of the dotted lines, pp, pp, while all that portion lying within the dotted lines, pp, pp, indicates a transverse vertical section of the common safety-valve alone. This increased area may be made by adding to a safety-valve already in use, or by casting the whole entire. I terminate this addition to the head of the valve with a circular or annular flange or lip, c, c, which projects beyond the valve-seat, E, E, Fig. 3, and extends slightly below its outer edge, fitting loosely around it, and forming the circular or annular chamber, D, D, whose transverse section, shown in the figure, may be of any desirable form or size. This flange or lip, c, c, fitting loosely around the valve-seat, E, E, is separated from it by about 1-64 of an inch, for an ordinary spring or balance. For a strong spring or balance this space should be diminished, and for a weak spring or balance it should be increased, to regulate the escape of the steam, as required. Instead of having the flange or lip, c, c, project beyond and extend below and around the outer edge of the valve-seat, as shown in Fig. 3, a similar result may be obtained by having the valve-seat itself project beyond the outer edge of the valve-head, and terminating it with a circular or annular flange or lip, extending slightly above, and fitting loosely around, the outer edge of the flange or lip, c, c, of the valve-head; but I consider the construction shown in Fig. 3 preferable. With my improved safety-valve, constructed as now described, and attached to the generator in the usual way, the steam, escaping in the direction indicated by the arrows in Fig. 3, first lifts the valve from its seat at the ground joint, F, F, and then, passing into the annular chamber, D, D, acts against the increased surface of the valve-head, and by this means, together with its reaction produced by being thrown downwards upon the valve-seat, E, E, it overcomes the rapidly increasing resistance of the spring or balance, lifts the valve still higher, and escapes freely into the open air until the pressure in the generator is reduced to the degree desired, when the valve will be immediately closed by the tension of the spring or balance. The escape of the steam by means of this safety valve is so certain and free that the pressure of the steam in the generator or boiler will not increase beyond the point or degree at which the valve is set to blow off."

The claim of the patent is this: "What I claim as my improvement, and desire to secure by letters patent, is a safety-valve with the circular or annular flange or lip, c, c, constructed in the manner, or substantially in the manner, shown, so as to operate as and for the purpose herein described." On the second of June, 1879, the same plaintiff brought a suit in equity, in the same court. against the same defendant. for the infringement of letters

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patent No. 85,963, granted to the same George W. Richardson, January 19, 1869, for an improvement in safety-valves for steam boilers or generators. So much of the specification of the patent as is involved in this suit is as follows:

"Be it known that I, George William Richardson, of Troy, in the state of New York, have invented certain new and useful improvements in safetyvalves for steam boilers or generators; and I do hereby declare that the following is a full, clear, and exact description thereof, reference being had to the accompanying drawings making part of this specification, in which Fig. 1 is a vertical section of the safety-valve and its connections, taken in the plane of the axis of the valve-stem; Fig. 2, a horizontal section taken in the plane of the line, A, a, of Fig. 1; and Fig. 3 another horizontal section at the line, B, b, of Fig. 1. Fig. 4 is a vertical section taken in the plane of the axis of the valve, representing a modification of my said invention; and Fig. 5 a horizontal section thereof, taken in the plane of the line, C, c, of Fig. 4. My said invention relates to improvements in the invention described in letters patent granted to me, and bearing date the twenty-fifth day of September, 1866, which said patented invention relates to a means for providing a more free escape for the steam than could be obtained by safety-valves as constructed prior thereto, and to insure the keeping of the valve open until the pressure of the steam in the boiler or generator falls below the pressure which was required to open it; the said means so patented consisting in forming the valve with a surface outside of the ground joint, for the escaping steam to act against, the said surface being surrounded by a projecting or overlapping lip, rim, or flange, leaving a narrow escape for the steam when the valve is opened, but which, although of greater diameter than the valve-seat, by reason of the said lap, presents a less area of opening for the escape of steam than is produced at the valve-seat, so that the steam which escapes through the area between the valve shall exert pressure against the said surrounding surface, and thereby not only open the valve completely, but hold it up until the pressure of the steam in the boiler falls below the pressure by which the valve was opened.

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"One part of my present invention relates to a means for regulating or adjusting the area of the aperture for the escape of the steam after acting on the said surface outside of the valve-seat, so that the valve may be set to close at any desired pressure below the pressure which will open it; and this part of my invention consists in making the aperture or apertures for the escape of the steam, after it has acted on the said surface outside of the valve-seat, adjustable. I will first describe the preferred mode of application of my said invention, as represented in Figs. 1, 2, and 3 of the accompanying drawings. In the said figures, a represents the valve-seat, which is to be attached to a steam boiler or generator in the usual or any other suitable manner, and which is formed, in the usual manner, with a beveled seat from the valve, b, fitted thereto by what is well-known as a 'ground joint.' * * * It is desirable that, so soon as the pressure of the steam in the boiler or generator reaches the pressure at which it should be relieved, the safety-valve should open wide for the free escape of steam, and that the valve should remain open until the pressure in the boiler is reduced below the pressure by which the valve was opened, and that it should be so organized that the en gineer may be able to adjust it so that it will close at any desired number of pounds pressure below the pressure at which it was opened. To accomplish these results was the main object of my said invention.

"To the upper surface of the valve, I secure a cap-plate or annulus, m, formed with a downward-projecting flange, n, at its outer periphery, leaving an annular space, o, all around between the outer periphery of the valve and the inner periphery of the flange, n, of the said cap. And the upper surface of the valve-seat, a, is extended all around, a little beyond the outer periphery

of the flange, n, of the cap, leaving an annular surface, p, surrounded by an upward-projecting rim, q, the plane of the upper edge of which, when the valve is closed, extends a short distance above the plane of the lower edge of

the flange, n, of the cap. The said cap-plate, m, is connected with the top of the valve by studs, r, r, or cast with it, in such manner as to leave an open space, s, between the two, for the passage of steam to the central aperture, t, in the cap, through which steam can escape when the valve is lifted from its

A

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seat. This central aperture is surrounded by a projecting cylindrical flange, threaded on the outside, to which is fitted a threaded ring, u, that can be turned up or down to any desired elevation, and there secured by a set-screw, The disk-like projection, f, on the valve rod or stem, e, extends over the said central aperture, t, in the cap-plate, m, and at such an elevation that the upper edge of the adjustable ring can be set in contact with it, or let down so far below it as to leave sufficient space for the free escape of steam.

"From the foregoing it will be seen that, when the pressure of steam in the boiler or generator becomes sufficient to lift the valve from its seat, it acts against the surface of the annular space, o, between the bevel of the valve-seat and the downward-projecting flange, n, of the cap, to assist in lifting and holding up the valve, particularly when the valve is borne down by the tension of a spring, which presents an increasing resistance as the valve is lifted. If the projecting rim, q, were in the same plane with the lower edge of the flange, n, the diameter of these parts being greater than that of the valveseat, on the lifting of the valve and cap, the area of the opening between the flange, n, of the cap, and the projecting rim, q, would be greater than the area of the opening between the valve and its seat, just in proportion as the diameter of the one is greater than the other, and the steam escaping from the valve would pass unchecked between the flange, n, and rim, q, and would not exert any force against the surface of the annular space, o; but, as the rim, q, extends above the lower edge of the flange, n, of the cap-plate, it follows that the aperture between the valve and its seat, by the lifting of the valve, is always greater than the aperture between the flange, n, and the rim, q, and hence the escaping steam, by its elastic force, will act against the surface of the annular space, o, to assist in lifting and holding up the valve until the pressure in the boiler or generator falls below the pressure by which the valve was first opened. The difference between the pressure against which the valve will close and the pressure by which it will be opened will depend upon the distance between the outer periphery of the flange, n, of the cap-plate and the inner periphery of the projecting rim, q. To render this adjustable, the area of the aperture for the escape of steam beyond the valve-seat must be adjustable. This is effected by the raising or lowering of the ring, u. If it be set to its lowest position, the steam escaping from the valve will be free to escape between the top of the valve and the cap, through the central aperture, and thence between the upper edge of the ring, u, and the disk, f, without materially aiding to lift or hold up the valve; but, by setting the ring, u, nearer to the under surface of the disk, f, and thereby reducing the space for the escape of steam, it will be caused to act, by its elastic force, against the annular space, o, of the cap-plate, and thus assist in lifting the valve and holding it up. "I have described and represented this as the simplest mode of adjusting the area of the aperture for the escape of the steam after it passes the valveseat; but it will be obvious that the same result may be attained by equivalent means, such, for instance, as making the ring, q, in adjustable segments, so that its diameter can be increased or diminished; but this would be mor complicated than the mode first and fully described; and it will also be obvious that the devices for holding up the valve may be inverted, as represented in Figs. 4 and 5 of the accompanying drawings, in which a' is the valve seat, and b' the valve, with its beveled ground joint, the valve-seat, a' having a flat annular surface, c', beyond the bevel, and the valve an annular surface, d', with a downward-projecting flange, e', the lower edge of which, when the valve is closed, extends a little below the plane of the surface, c', of the valve-seat, and a narrow annular space being left for the escape of steam between the inner periphery of the said flange and the outer periphery of the valve-seat, a', as set forth in my patent of September 25, 1866."

The claim of the patent is as follows: "What I claim as new, and desire to secure by letters patent, is the combinatio of the surface beyond the seat