Search Images Maps Play YouTube News Gmail Drive More »
Sign in
Screen reader users: click this link for accessible mode. Accessible mode has the same essential features but works better with your reader.


  1. Advanced Patent Search
Publication numberUS725707 A
Publication typeGrant
Publication dateApr 21, 1903
Filing dateNov 15, 1902
Priority dateNov 15, 1902
Publication numberUS 725707 A, US 725707A, US-A-725707, US725707 A, US725707A
InventorsLouis E Hoffman
Original AssigneeLouis E Hoffman
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
US 725707 A
Abstract  available in
Previous page
Next page
Claims  available in
Description  (OCR text may contain errors)

No. 725,707. PATENTED APR. 2l, 1903. L. E. HOFFMAN.




m: mams nnen; no., vnovamuo. msninnmn. n. c.



SPECIFICATION forming part of Letters Patent No. 725,707, dated April 21, 1903.

Application led November 15,1902. Serial No. 131,553. (No model.)

To all whom it may concern.-

This invention relates to boiler-feeders,

and is particularly designed for use in connection with asher-boilers used on motorvehicles.

The object of the invention'is to produce an automatic feeder having advantages of simplicity and safety regulated by a pressuregovernor controlling the delivery of Water from the source of water-supply to the boiler.

Speaking generally, the invention comprises a tank and a boiler and a feed-water pipe connecting the same, said pipe having a pump, a by-pass around the pump and back to the tank, anda regulator actuated by the pressure to control the passage of water in the by-pass, and consequently into the boiler. The accompanying drawing is a side elevation, partly in section, the parts being represented in 4the same plane for the sake of clearness.

Referring specilically to the drawing, 6 indicatesy a water-tank; 7, the boiler with the burner 7IL thereunder; 8, the supply pipe from the tank to the boiler, having a checkvalve 8f.

9 is the pump, actuated by attachment to any moving part of the machine.

10 is the by-pass and 1l is the regulator controlling the same.

The regulator-casing contains a diaphragmv The by-pass l0 joins the main pipe 8 between the pipe llb and the check-valve 8a. Consequently the by-pass connection and the regulator connection are outside the check-valve. This is important for the following reason: the diaphragm of the regulator does not receive the presso re in the boiler. This pressure varies constantly and sometimes reachesahighpoint, which, were it not for the check-valve, would strain the regulator and, perhaps, Wreck the same. By the arrangement shown the checkvalve remains closed until the steam-pressure in the boiler falls below that of the spring, when the valve opens and the Water is fed into the boiler. When the steam-pressure is higher than that of the spring, the pressure in the feed-pipe created `by the pump will at a predetermined point overcome the spring and lift the valve 10a, permitting the water to escape through the by-pass until the equilibrium is restored. It is unnecessary to stop the pump, and it will he seen that the diaphragm of the regulator never receives pressure more than slightly in excess of the springpressure. Stated in another way, the pressure is equal on the check-valve and thediaphragm, and when this pump-pressure reaches a predetermined amount equal to the pressure of the spring the diaphragm rises and lifts the valve 10CL from its seat, thus relieving the pressure on the diaphragm by release of the Water through the by-pass. A very even liow of water is eiected, because the check-valve will not open until the steam-pressure falls below the pressure maintained in the feedpipe. When it does so fall, the check-valve opens, and the water being flashed into steam the check-valve closes instantly, relieving the regulator and the feed-pipe of the boilerpressure, which is often intense.

The invention produces an automatic feeder of great simplicity, the parts of which are maintained in substantial equilibrium and subjected to no great strain or sudden change of pressure.

What I claim as new, and desire to secure by Letters Patent, is'- 1. The combination with a` water-tank, boiler, and feed-pipe connecting the same, the pipe having a check-valve opening to the boiler, of a pump forcing water against the check-valve, a valved by-pass joining the .www i the latter, and a. relief-,valve between the pump and the check-valve, opening under the pum p-pressure' when the boiler-pressure exceeds a predetermined point.

In testimony whereof I afx my signature in presence of two Witnesses. l


VVitu esses:


Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US2440072 *Feb 24, 1945Apr 20, 1948Plessey Co LtdHydraulic pump
US2513833 *Sep 2, 1943Jul 4, 1950Bendix Aviation Corporationwinkler
US2531669 *Feb 14, 1945Nov 28, 1950Bendix Aviat CorpAccumulator valve
US2539977 *Feb 21, 1946Jan 30, 1951Staude Edwin GUnloading valve
US2672096 *Jun 21, 1948Mar 16, 1954Kroldrup AxelManeuvering device for propeller shafts
US2834337 *Sep 7, 1954May 13, 1958Fred H Schaub Engineering Co IWater heating system
US6257792Mar 25, 1999Jul 10, 2001Camco International Inc.Retaining ring
Cooperative ClassificationF04B49/24