Specification of John Justice : stove grates.

  • Justice, John.
Date:
1854
Catalogue details

Licence: Public Domain Mark

Credit: Specification of John Justice : stove grates. Source: Wellcome Collection.

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    Justices Improvements in the Construction of Stove Grates, Qc. tioned bar descends perpendicularly instead of ascending like tbe one attached to the fire grate. This descending bar on the side farthest from but parallel to the front of the stove grate has a rack which falls on that side of the pinion before named, which is opposite to the part working in the rack of the ascend¬ ing bar before mentioned, that is, one pinion or small wheel works into the 5 racks of both, and of course when the descending bar is in action the motion of the two racked perpendicular bars are opposite and contrary, the one ascending while the other is descending. But the descending bar is not furnished with a rack throughout its whole length, but only so much of it is so furnished as the length of space through which the plates of the blower are to descend. The said 10 descending perpendicular bar is made fast only to one of the plates of the blower, namely, that one which is to descend lowest; the other plate descends by its own weight, and is furnished with two or more pins which, coming against stops placed at a suitable height, prevents its descending lower and keeps it stationary, while the other attached to the descending bar continues to 15 descend by the motion communicated by the rack, till by its descent and the ascention of the grate, the two, videlicet the blower and the grate, are brought close together (if need be), so that when in this position no air can enter the chimney without passing through the fire. When the blower is wound up it will be seen, from the foregoing description, that the ascending bar carries up 20 the lower plate only of the blower, but the lower plate is furnished with two or more pins which in its ascent come against stops in the upper plate, by which means the upper plate is also carried up, and both get out of sight behind the top or lintel of the front of the stove. It is only necessary further to state that the descending perpendicular bar is kept suspended when not in action (which 25 $ , it is convenient should be the case during some part of the rising of the fire grate) by means of a lever, the pin or fulcrum of which is fastened to the outside or back of the outer cheek. One end of this lever meets a pin project¬ ing from the descending bar, while the other end is loaded with a counterpoise able to sustain the weight of the descending perpendicular bar and the blower. 30 This lever is placed in such a position that the loaded end passes over the horizontal arm by which the ascending bar is attached to the fire-grate, so that when the fire-grate is down near the hearth the lever is in action, keeping the descending bar at such a height that the rack on the said bar is disengaged from the pinion, but when the fire-grate is wound up to a certain height (by 35 turning the key) the horizontal arm of the ascending bar before mentioned reaches the loaded end of the lever, and in its ascent lifts up the said loaded end, suffers the descending bar to descend, and thus brings its rack into action with the pinion. A small bolt may be introduced to carry the weight of the