Nathan Mfg. Co. v. Delaware, L. & W R. Co.

• Decision Date: 07 November 1907
• Docket Number: 15.
• Citation: 157 F. 685
• Court: U.S. Court of Appeals — Second Circuit
• Parties: NATHAN MFG. CO. v. DELAWARE, L. & W.R. CO. et al.

157 F. 685

NATHAN MFG. CO. v. DELAWARE, L. & W.R. CO. et al.

No. 15.

United States Court of Appeals, Second Circuit.

November 7, 1907

Appeal from the Circuit Court of the United States for the Northern District of New York.

George S. Payson (John B. Corliss, of counsel), for appellants.

Edmund Wetmore, for appellee.

Before LACOMBE, WARD, and NOYES, Circuit Judges.

PER CURIAM.

The lubricators with which the patent is concerned are those which supply oil to the valves and cylinders of locomotive engines, which are continually surrounded by an atmosphere of steam, and which are therefore not accessible while the engine is in operation. They include a reservoir of oil, which is fed forward uniformly and continuously to the parts of the engine where it is required. The type of lubricator to which complainant's device is applied is what is known as 'hydrostatic,' because it depends for its operation on the force exerted by a column of water.

An illustrative drawing which is found in complainant's brief will make a condensed description of the operation of lubricators of this type more intelligible.

(Image Omitted)

Steam from the boiler is admitted through the steam pipe, A, into the condenser, B, where it condenses into water which flows through the water pipe, D, into the bottom of the oil reservoir, C. As it rises therein it lifts the oil till the latter flows over the top of the oil tube,

E. and down the same to the bottom of the sight feed glass, F. This glass is filled with water of condensation. The oil rises through it drop by drop, and, accompanied by the steam, flows out through the small or 'choke' passage, H, into the oil or tallow pipe, J, and thence to the steam chest and cylinder of the engine. The equalizing pipe, G, leads steam at boiler pressure from the steam pipe or condenser to meet the discharge end of the body of water and oil contained in the condenser and reservoir and the connecting channels to the exit at the choke passage. When the full head of steam is admitted to the cylinder from the boiler, as when the engine is running at full speed, the tallow pipe is full of steam at boiler pressure. When, however, the steam is shut off from the cylinder, as when the engine is running down a steep grade or slowing up to stop at a station, the pressure in the tallow pipe is much reduced, and the oil which is entering the receiving end of the tallow pipe through the choke passage with boiler pressure behind it has a tendency to be forced in in much larger quantities than when the tallow pipe is filled with steam at boiler pressure. This produced unfortunate results, which need not be detailed. The problem presented was this: If the choke passage were made large enough to insure a flow of oil when there was full back pressure in the tallow pipe, it would be liable to allow an excess of oil when the steam was shut off from the tallow pipe. Indeed, in the latter case the oil might be sucked through the choke passage so rapidly as to empty the reservoir. Complainant concedes that this difficulty had been recognized and means devised to meet it before Woods' invention, and contends that what Woods did was to invent a new and more efficient means for accomplishing this purpose.

Turning now to the patent, we find this statement:

'Owing to the fact that the steam supply for the lubricator comes direct from the boiler, it is evident that the escape of steam and oil through the upper sight brackets is practically continuous, even though the throttle valve be closed and the engine motionless. It has been found however, that when the throttle valve is opened and steam admitted to the steam chest the small volume of steam passing through the nozzles condenses within the oil pipes resulting in a reduced pressure therein. The reduced pressure is not sufficient to resist the back pressure of steam from the steam chest, with the result that the feed of the lubricator becomes irregular and eventually stops altogether. It is the object of my invention to overcome this effect in a simple and reliable manner. To this end I combine with the lubricator and the oil or tallow pipe leading therefrom to the cylinder, * * * through which pipe there is a constant flow of steam and oil in limited quantity to the cylinder through the usual plug or nozzle, or its equivalent, a valve or piston plug, preferably of the differential type, controlling a steam passage from the lubricator side of the apparatus to the tallow pipe and adapted to be operated by the back pressure from the cylinder. * * * Thus not only is the back pressure from the cylinder neutralized or equalized by the additional volume of steam admitted at the lubricator end of the tallow pipe, but the oil feed is increased also. In other words, the feed is increased when the throttle is open and decreased when the throttle is closed, because in the latter case the oil can pass through the small constantly open choke passage or plug only. These features, broadly considered, are not new with me, as a lubricating apparatus embodying said characteristics is shown and described in United States patent No. 267,430, granted to R. J. Hoffman on January 14, 1882.'

The patentee then describes in detail the 'piston plug, preferably of the differential type' above referred to. It is a longitudinally moving valve provided with a restricted constantly open port or passage (the choke passage) through it, for a continuous supply of steam and oil in minimum quantity from the lubricator to the tallow pipe, and with additional ports or passages (distinct and separate from the constantly open minimum supply port) which are open for the passage of an additional supply of steam or steam and oil only when the piston valve is operated to move by the back pressure from the cylinder. Thus the piston valve, so far as its restricted, constantly open passage is concerned, corresponds in function to the choke plug usually employed at the lubricator end of the tallow pipe, while, so far as its additional ports are concerned, it is a valve which controls said ports and opens them only when operated so to do by back pressure from the cylinder. After describing in detail the structure and operation of this form of valve, the patentee says:

'I believe myself to be the first to have devised a

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