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Publication numberUS465767 A
Publication typeGrant
Publication dateDec 22, 1891
Filing dateApr 11, 1891
Publication numberUS 465767 A, US 465767A, US-A-465767, US465767 A, US465767A
InventorsFrank St
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Half to john b
US 465767 A
Abstract  available in
Previous page
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Claims  available in
Description  (OCR text may contain errors)

(No Model.)


Patented Dec. 22, 1891.





SPECIFICATION forming part of Letters Patent No. 465,76*?, dated December 22, 1891.

Application nea April 11, 1891.

To all whom t may concern.-

Beit known that I, FRANK ST. CLAIR, residing at Manchester, in the county of Hillsborough and State of New Hampshire, have invented certain new and useful Improvements in Low-Tater Alarms, of which the following is a specilication.

This invention relates to an improved lowwater alarm for steam-boilers, andis adapted 1o to indicate visibly and audibly when the water reaches a certain level, and it is also adapted to sound an electric signal at any particular time and place.

With these objects n view my invention consists in the peculiar construction of the various parts and their novel combination or arrangement', all of which will be more fully hereinafter described and claimed.

In the drawings forming a part of this 2o specification, Figure l is a perspective view of my improved device. Fig. 2 is a central vertical section, and Fig. 3 is atop plan View.

In carrying out my invention I employ a cylinder A, which is connected with the boiler B by means of the water-pipe w and steampipe s. The heads of the cylinder are held on by the rods A', the upper portions of said rods extending a considerable distan ce above the top head, as clearly shown. Within the 3o cylinder is arranged a piston C, and connected with the same is a tubular piston-rod D, said rod passing through the top head of the cylinder, and upon its upper end is arranged a steam-whistle E. An aperture CZ is made in the tubular rod at a predetermined point, the purpose of which is to allow the steam to enter the rod and sound the whistle when the water in the boiler sinks, and allows the piston to descend until the aperture 4o d is within the cylinder.

A gage-plate F is connected with the boiler, and upon the opposite side of the cylinder is arranged an electric push-button G, and in connection therewith an elbow-lever G.

A horizontal pointer-arm H is secured to the tubular rod D a short distance below the whistle E, said arm being rigid with the rod D and sliding on the upper portions of the rods A', which act as guide-rods. One end of 5o the pointer-arm rests adjacent to the gage- Serial No. 388,569. (No model.)

plate F, and is adapted toindicate visibly the level of the water in the boiler, and the opposite end of the pointer-arm is adapted to engage the elbow-lever operating the electric push-button and sounding a signal at any particular place.

Any suitable number of push-buttons and connections may be arranged in connection with my apparatus to give any number of signals. 6o

From the above the operation and advantages of my device will b e apparent to every one skilled in the art to which it pertains.

Having thus described my invention, what I claim is* l. The combination, with the cylinder, the steam and water pipes communicating therewith, the piston, and tubular piston-rod provided with an aperture and with awhistle at its end, of a gage-plate, electrical alarm con- 7o nections, and a rod secured to the piston-rod and carrying an indicator at one end and an arm at the other adapted to close the electrical circuit, substantially as set forth.

2. The combination, with the cylinder, the steam and water pipes, the piston, and pistonrod provided with a whistle, and the guiderods projecting upwardly from the cylinder parallel with the piston-rod, of the gage-plate, the electrical alarm connections, the trans- 8o Verse rod carried by the piston and working upon the guide-rods, said transverse rod carrying an indicator at one end of an arm at the opposite end adapted to contact with the electrical'connections, substantially as and 85 for the purpose set forth.

3. The combination, with the cylinder, the steam and water pipe, the piston and pistonrod, and the guide-rods projecting upwardly from the cylinder parallelwiththe piston-rod, 9o of the gage-plate and the indicator carried by the. piston-rod and working upon the guiderods, substantially as and for the purpose set forth.

In testimony whereof I affix my signature in vpresence of two witnesses.

FRANK ST. CLAIR. lVitncsses:


Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US4757305 *Jan 5, 1987Jul 12, 1988Dominic PesoWater level indicator
Cooperative ClassificationG01F23/74