Invalidity dossier
US 107492
Improvement in adjustable arms for working slide-valves
Added 9/23/2026, 1:05:46 PM
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Patent summary
Title, assignee, inventors, filing/issue dates, abstract, and a plain-language overview of the claims.
Patent Overview — US 107,492
Title: Improvement in Adjustable Arms for Working Slide-Valves
Inventor: Hubbard Hendrickson, of Red Bank, Monmouth County, New Jersey.
Dates: Patent No. 107,492, dated September 20, 1870 (source lists prior art date and publication date as 1870-09-20).
Assignee: None identified in the supplied excerpt.
Purpose: The invention relates to slide-valve adjusting arms. Its stated object is to effect certain improvements therein, set out and specified in the claim. The adjustable arm (a valve-crank) is meant to regulate the motion imparted to a steam-engine slide-valve.
Plain-language scope: A rotating driving-shaft (A) carries an eccentric that drives a rock-shaft (B) through a connecting-rod (C) and crank (D); the rock-shaft in turn works the slide-valve (E) in the steam-chest. The crank D has an arc-shaped slot with stops whose edges are arcs struck from the axis of rod C. An adjustable slide (F) runs in this slot and carries a projecting pin (c) to which rod C is secured. A swivel-nut (d) inside the slide swings on a straight screw (G) threaded lengthwise through the crank, so turning the screw moves the slide and pin higher or lower in the slot; the swivel-nut lets the slide swing during the different movements. Adjusting the pin toward or away from the shaft increases or diminishes the arc through which the rock-shaft vibrates, and hence the valve's forward throw; adjustment on a radial line from rock-shaft B would affect forward and backward throw equally. Alternatively, crank D may have a curved groove or rail instead of a slot. A notched or marked plate (e) on slide F, with a spring or pointer (f) fixed to the crank, indicates the pin's position and its effect on valve motion.
Claims: (1) The arc-slotted arm D and slide F c, combined with nut d and straight screw G. (2) The slotted arm D and slide F c, combined with notched plate e and pointer f.
Source: https://patents.google.com/patent/[US107492](/patent/US107492)/en
What the excerpt does not establish: It does not identify any assignee or owner, does not describe the drawing figures beyond their captions, does not give filing, priority, or expiry specifics beyond the listed dates/status, and does not establish validity, infringement, or the content of prior art.
Generated 10/1/2026, 9:53:17 PM
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Assignment history
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Prior art
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