USRE3644E - Improvement in grates - Google Patents

Description

naar @safe aan one. N

GEORGE L. SMITH, O F BRO.KLYN,'NEIV YORK.

Letters Paten-t No. 42,118, (lated M forely @f1-864; reissue No. 3,644, dated Srqitember 21, 1869.

w I IMPROVEMENTIIN AG-RATIEIS.

The Schedule referred to in these Letters Patent and making part of the same-L m To all whom it may concern:

Be it known that I, Gnoncn L. SMITH', of Brooklyn, in the county of Kings, and State of' New York, have invented 'a new and improved Grate for Boilers and other Furnaces; and that the following is a full and exact description thereof, reference heilig had to the accompanying drawings, and to the letters of reference marked thereon.

Figure l is a perspective sectional view of the su porting and bearilig-bars requisito for a boiler and-also of a section of my improved grates l position upon the same;

Figure 'is a plan view of a set for use form or even temperature, and thus remove or diminish the tendency in the metal to warp or spring out of truc.

In case of the destruction or failure of the. portion of them subjected to the most intense heat, 'they can be vreplaced at small expense and little time.

By thus forming the grate in sections, and at the saine time so forming the openings i'or the passage of air through them to the fire, the said openings effect the double object of giving increased area for the admission of air, and of giving increased opportunity oi' clearing the surface from cinders and clinkers by the use of the slice-bar.

The advantage of my invention lies in the greater` ease and facility of removing jthc einder and clinker from the grate-surface, bythe' shearing-like action of the slice-bar or hoe, due to the diagonal or angular openings Fig. 2, in the accompanying drawings, shows the exact forni and proportion I consider preferable, and have adopted. 5

A A are the small gratas, as described;

B B are longitudinal bearers supporting- A A; and' G'-is the -ordinary grate-bar bearer, supporting the whole.

I will' designate the `several portions of my` castings A as follows: l

The angular or V-shaped partsalong tne central portion .of each section are marked c;

.The corresponding angular or V-spaces between them are marked in; and

The several pieces which join these near each side are marked al and a2 rlrhe openings-m being V-shaped, allow the corresponding parts a to expand and contract, without distorting the general shape.

An expansion in anyportiou only results in makin (Y c the V- shape more oblique or more strongly marked.

This change does no t alter the general shape or distort in any manner the entire piece of casting.

The arrangement of these apertures m is such as throws the angle oi' all inthe same direction, and thus the expansion and contraction move all inthe same direction, without involving any appreciable change in the width oi" the spaces for the air, and prevent 'actures of the grate-bar by all strain from r expansion beiugrelieved.

I would have it understood that I do not confine myself .to the exact proportion ot' the gratefbars or sections here shown. They may vary in length and width to suitfcirciunstances, andthe various sizes and uses of' the dilierentA furnaces when they may be used.

l)- furnace, ocated in of grates as placed Figure 3 is a transverse longitudinal section of iig. 2; `and v Figure 4 is a plan view o1" the bearing-barY B, which l.is-made ^shape in its upper face, 'so that the passage of air to the grate resting upon it shall be unobstructed.

Great diiiiculty has heretofore existed in forming and maintaining level and uniform surfaces of the grates (and air-passages in the same) of steam-boiler and other furnaces, and a great variety of' grate-bars, both single and in sections or clusters of more than one,- has been used.A l

It is well known that equal given piece of metal, in its var equal expansion and contr temperature in any ions parts, produces action in the same, without strain in any part, while unequal'temperatures applied to the same piece of metal, in its various parts, pro` duces great strain, and often produces fractures, and always tends to spring or varp it ont of shape. This ,principle applies tothe gratos oi' steam-boiler and other furnaces.

My invention aims to overcome all these 'objections- First, by forming the airthrough the grate, in the form drawing, so that lthe slice-bar, in passing over the openings, shall have a shearing or cutting -action against the clinkers or cinders lying over or upon, or which project down into the openings, tending to crush and remove more speedily than if the openings were parallel to or transverse to the line of depth of' furnace; Second, hy forming such grate, fig. 2, in small sections, such small sections or blocks having air-spaces through them, formed obliquely or zigzag, as shown, and of uniform size, either square or oblong, or other shape, that will, when fitted together, form a continuous grate-suriiure, and that each section or block will be, in all its parts,

subjected substantially to a unipassages, or openings shown in the attached :Le u

2 l v l v l Having thus fully described my invention, widtll of the grate, inl combination with the oon- Vhnt I claim es new, and desire to secure by`Letstrneting of the seid grate of a series of sections, ters Patent, is as follows: s* substantially as shown and for the purpose described. 1. Arranging the air-passages or openings in fnr- In testimony wfhereof, I have hereunto set my .neee-gretes diagonal or oblique to the length or Width hand, in the presence of two subscribing Witnesses. of the grate, as shown and described, and for the purj i GEO. L. SMITH. pose set forth. Witnesses:

2. The arrangement of the air-passages or open- W. O. DEY, ings within @mace-gratos. oblique tothe length or F, A. HADlGKE.

Images