Giffard’s Patent Model of a Steam Boiler Injector – ca 1860
date: label: date made
content: 1860
label: patent date
content: 1860-04-24
name: label: inventor
content: Giffard, Henry
notes: label: Description
content: This model was filed with the application to the U.S. Patent Office for Patent Number 27,979 issued to Henri Giffard of Paris, France on April 24, 1860. The patent was for an improved method of supplying water to a steam boiler.
label: Description
content: Early boilers operated at such low steam pressures that introducing feed water into the boiler could be done by simple pumps that filled elevated reservoirs. The water flowed into the boiler by its own weight. However, as pressures increased it became necessary to force water into the boiler by increasingly powerful pumps. Giffard’s invention was for a means of injecting the water into the boiler by the force of the steam itself. Unlike pumps, the Giffard injector had no moving parts.
label: Description
content: Giffard’s concept was to push a high velocity jet of steam through a small nozzle which was surrounded by an annular space connected to the feed water reservoir. The jet created a partial vacuum which drew water from the reservoir. The mixture of condensed steam and water was then pushed at high speed into a gradually diverging pipe which slowed the flow while maintaining a pressure slightly above the pressure of the steam in the boiler.
label: Description
content: In the image of the model steam is supplied to the injector via the pipe and valve at the upper left. The lever at the far left controlled the flow of steam to the nozzle. The larger pipe at the bottom center connected to the reservoir, and the smaller pipe to its right was for unneeded water to return to the reservoir. Glass sight ports between these pipes allowed visual inspection of the flow. The gradually diverging pipe section is between these ports and the exit valve at the upper right.
label: Description
content: The patent model is constructed of brass and steel. This model is actually a standard commercial model that was being manufactured in France prior to the patent application. A full description of the operation of the injector along with complete diagrams of the patent can be found in the patent document online at the United States Patent and Trademark Office website, www.uspto.gov.
place: label: place made
content: United States: Pennsylvania
label: associated place
content: France: Île-de-France, Paris
topic: label: Subject
content: Patent Models
label: Subject
content: Steam Engines
setName: label: See more items in
content: Work and Industry: Mechanical and Civil Engineering
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content: Engineering, Building, and Architecture
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content: Patent Models
label: Exhibition
content: Power Machinery
label: Exhibition Location
content: National Museum of American History
publisher: label: Related Publication
content: Frank A. Taylor. Catalog of the Mechanical Collections of the Division of Engineering United States National Museum, Bulletin 173
dataSource: label: Data Source
content: National Museum of American History
identifier: label: ID Number
content: MC.309368
label: catalog number
content: 309368
label: accession number
content: 89797
label: patent number
content: 27,979
objectType: label: Object Name
content: injector, steam, model
label: Object Name
content: patent model, injector, steam
physicalDescription: label: Measurements
content: overall: 14 in x 21 in x 4 in; 35.56 cm x 53.34 cm x 10.16 cm