Improvements in Furnace Grate Bars.
Year: 1889

page_text: Date of Application, 31st Dec., 1889-Accepted, 1st Feb., 1890
COMPLETE SPECIFICATION.
Improvements in Furnace Grate Bars.
I, HUGH DONALD FITZPATRICK of 70 Wellington Street, Glasgow, Lanarkshire
Registered Patent Agent do hereby declare the nature of this invention, a communi-
cation to me from abroad by the Improved Zig-zag Grate Bar Company of St. Louis,
Missouri, United States of America, and in what manner the same is to be performed,
to be particularly described and ascertained in and by the following statement
:-
In this invention each grate-bar is composed of two or more zigzag portions or bars
connected at intervals. The bars have gudgeons at the ends upon which they may
be rocked.
The novelty consists, partly, in the tooth or projection at the salient angles of the
bars, and also certain details of construction in the grate bars and side bars and
rocking devices specifically set forth in the claims.
Figure 1 is a perspective view of a furnace grate composed of my improved bars.
Figure 2 is a perspective view of a grate bar.
Figure 3 is a perspective view of an end bearing bar.
Figure 4 is a perspective view of a side bar.
Figure 5 is a perspective view of a shaker-bar.
Figure 6 is a longitudinal, vertical section on a plane passing through the axis of
one of the shaker shafts and showing one of the grate bars in side elevation.
Figure 7 is a transverse vertical section at 7-7 Fig. 6, looking forward and showing
the shaker-bar in rear elevation.
Figure 8 is a detail perspective view of one of the angular breaker teeth.
The front carrying bar 1, rear bearing bar 2 and side bars 3, 3, are shown jointed
together at the corners and connected by bolts 4. The side bars are shown with lugs 5
which are bolted to the upper ends of the supporting legs 6, but this manner of
connecting and supporting the bearing frame 1, 2, 3, 3 may be varied without
essentially changing the principle of the invention. The front and rear bearing bars
have recesses 7 in which the gudgeons 8 of the grate bars have bearing; and these
recesses are closed at top by a plate or bar 9 secured to the bearing bar by screws 10.
Each grate bar has two or more zigzag bars 11,11, running side by side from end to
end of the bar; said ends, 12, being cast integral with the bars 11, and the gudgeons 8.
It is preferred that the bars 11 have at top a shallow channel 13 to contain ashes
to act as a partial non-conductor of heat. 14 are transverse connections between the
bars 11, 11 cast integral with said bars. The ends 12 have depending lugs 15 through
which pass the ends of a truss-bar 16, the ends of the truss-bar being secured in or to
the lugs. 17 is a strut which depends from the middle of the grate bar and which
has a notch to receive the middle of the truss-bar, as seen in Fig. 6 ; the truss-bar
serving to prevent the settling of the grate bar when heated.
The salient angles 18 of the grate bars project, in the upper part of the bar, beyond
the lower portion 19 of the bar forming a tooth for the agitation of the coal and
breaking of clinkers, when the bars are rocked. This tooth has an acute point 20
from which the face 21 recedes upwardly, as shown in Figs. 7 and 8. The under
side 22 of the tooth is recessed or concaved, (as seen in Figs. 7 and 8) in order to
render the edges 23 acute. The object in making the point 20 and edges 23 acute is
to increase their effectiveness in breaking clinkers.
Those lugs 15 which are at the front end of the bars have downward extensions 24
that are slotted transversely to receive lugs 25 upon the rocker-bar 26. 27 is a pin or
bolt passing through the lugs 25, and lug-extensions 24 so that the rocker bar hangs
upon the grate bar. The shaker bar has a vertical slot 28 receiving the pin 29 of a
crank 30, whose shaft, 31, has bearing in the socket of a bearing piece 32 cast
upon the front bearing bar. The shaft has an end 33 suitably formed to receive a

page_text: key or lever by which the crank shaft is rocked to cause the rocking of the bars through
the medium of the rocker bar 26. The crank shaft 31 is put into its bearing 32 from
the rear end of the bearing and is held in place by a washer and pin, 34, 35 or any
other suitable means. It is preferred, especially where the grate is wide, to arrange
the grate bars in two or more sets with separate rocking devices, so that less power
will be called for in performing the operation. The side-bars 3 have a number of
inwardly projecting ribs 36 which enter the recesses of the re-entering angles 37 of
the grate-bars which are adjacent to them. The side bars have upon the outer side,
projections 38 which are cast shorter or longer so as to fill the space between the body
of the side bar and the side wall of the furnace. Thus air may pass between the side
bars and the furnace walls. 39 are snugs cast upon the side-bars, and which engage
in recesses of the front and rear bearing bars.
Having now particularly described and ascertained the nature of my said inven-
tion and and what manner the same is to be performed I declare that what I
claim is :-
1. A rocking, zigzag grate-bar having its salient angles cut away at the lower part,
leaving the upper part projecting, substantially as set forth.
2. A rocking grate-bar composed of two or more zigzag bars having their salient
angles cut away at the lower part, leaving the upper part projecting, substantially as
and for the purpose set forth.
3. A zigzag grate-bar having teeth at the salient angles with acute points 20 and
edges 23, substantially as set forth.
4. The combination of zigzag grate-bars and side bars having projections 36,
substantially as shown and described, extending into the spaces at the re-entering
angles of the grate bars.
5. The combination with a zigzag grate-bar of a truss-bar or rod connected to the
ends of the grate-bar and a strut 17 extending from the grate bar to the truss-bar or
rod, substantially as and for the purpose set forth.
6. The combination of zigzag grate-bars pivoted to the bearing bars, lugs depending
from the bars, a slotted rocker bar hinged to the lugs and a rocking crank shaft
having a crank pin extending into the slot of the rocker bar, substantially as and for
the purpose set forth.
Dated this 29th day of December 1889.
H. D. FITZPATRICK,
Glasgow.