Improvements in Pistons.
Year: 1890

page_text: Date of Application, 4th Mar., 1890-Accepted, 5th Apr., 1890
COMPLETE SPECIFICATION.
Improvements in Pistons.
I, HORACE SEE, a citizen of the United States residing in the City and County of
New York and State of New York, United States of America, Engineer, do
hereby declare the nature of this invention and in what manner the same is to be
performed to be particularly described and ascertained in and by the following
statement:-
vertical
My invention relates to the pistons of either horizontal, diagonal or
engines, and its object is such a construction of a piston as will permit of adjust-
ment to compensate for wear and of centering without the employing of a tail rod,
and such a construction, moreover, as will insure the interception of the passage of
steam and prevent undue friction.
To the foregoing ends my invention comprehends a piston a good form of a
convenient embodiment of which is represented in the accompanying drawings
and hereinafter described, the particular subject matter claimed as novel being
hereinafter definitely specified.
In the accompanying drawings,
Figure 1 is a side elevational view of a piston embodying my improvements.
Figure 2 is a central, vertical, sectional elevation through the same, in the plane
of the dotted line x-x of Figure 3, and sight being taken in the direction of the
arrows upon said line.
Figure 3 is a rear elevational view of the piston shown in Figures 1 and 2.
Figure 4 is a fragmentary, sectional elevation through a portion of the piston
represented in figure 3, in the plane of the dotted line y-y upon said figure, and sight
being taken in the direction of the arrows upon said line.
Similar letters of reference indicate corresponding parts.
In the drawings, A represents a piston, conveniently made of the form shown, and
provided with two piston rods B B. The rear face of the piston is turned off, or
otherwise conformed, to present three circumferential rearwardly-facing surfaces,
which are, respectively, herein termed the outer shoulder a, the middle shoulder a¹,
and the inner shoulder a². The planes or faces of these shoulders are preferably
parallel. C is what I term a follower; it being an angular ring of metal composite
of segments as hereinafter set forth, and conveniently of the form represented in the
drawings, that is to say, as to each segment having a horizontal member c terminating
in an upturned ring flange c¹ adapted to bear against the middle shoulder a¹ of the
piston, and a vertical member c² adapted to the inner shoulder a² of the piston, and
being as to all of its assembled segments adapted for application against said inner
and middle shoulders of said piston.
The wearing surface of the follower as an entirety is composed of the outer
peripheral faces of the horizontal members of its respective segments.
In the drawings I have represented the follower as composed of but two sections,
it is, however, to be understood that three, four, or more segments may, at will, be
employed.
At their intersections or joints the segments are not radially squared off, but are
respectively provided with overlapping tongues cx, figures 1 and 3, the meeting ends
of which are preferably correspondingly oppositely angled as particularly illustrated
in figure 1. The purpose of making the follower in segments instead of in a single
annular piece being, as stated, to permit of the radial outward adjustment of the
segments to effect the accurate centering of the piston and to compensate for wear,
the object of providing the meeting extremities of the segments with overlapping
tongues is to intercept the passage of steam or other fluid at the points of meeting
or separation. care what I term tongue plates, preferably formed of steel, which

page_text: are, as shown, secured in vertical planes at regions of the intersection or overlap
of the tongues. These plates not only serve as wearing surfaces in the adjustment
of the segments of the follower, but also assist to intercept the passage of the
steam.
The segments of the follower are secured to the piston by follower bolts D,
which pass through radial elongated bolt seats d in the said follower and thread into
the piston as shown. It is evident that by loosening or tightening the follower
bolts, the segments of the follower can be adjusted and fixed in their adjusted
positions.
In addition to the follower bolts, and in order to accurately gauge the radial set of
the segments of the follower, I employ in connection with each segment one, two, or
more, key plates or wedges E, the inner extremities of which are snugly fitted to
plate seats a* in the piston, the shanks of which pass through radial elongated shank
seats d in the follower, and the outer extremities of which are angled or overturned
to bear against the outer face of the segments to which said plates happen to be
applied and are provided with radial elongated bolt seats e through which pass the
shanks of key plate bolts F which thread into the substance of the segments.
As is obvious the radial set of a key plate with respect to its segment of the
follower is easily adjusted by the screwing or unscrewing of its bolt, while when the
desired set has been obtained the application of the plate to its seat in the piston
gauges the set of the segment of the follower to which it is applied. G are segments
of packing rings interposed between the outer shoulder a of the piston and the
flange c¹ of the follower. These packing rings may be of any preferred description,
and are conveniently of a character invented by me and set forth in United States
Letters Patent No. 365,102, granted to me June 21st, 1887.
It will be apparent from a consideration of the foregoing construction that the
segments of the follower can be both removed and applied in the direction of the
length of the cylinder to which the piston is adapted without unseating said piston
from said cylinder. This capacity for application and removal of the follower
without unseating the piston constitutes one of the material advantages of my
invention.
Such being a description of the construction of a piston embodying my improve-
ments, it is obvious that each segment of the follower may be independently set out
by the means of adjustment described, and may, if desired, be likewise adjusted by
the insertion of packing between its inner peripheral face and the piston. It is
obvious that any segment of the follower when worn can be cheaply replaced, or that
it can be reshod or packed upon its wearing surface.
The forms of parts represented in the accompanying drawings are well adapted to
subserve the ends of my invention,-I do not however confine myself to such forms,
as neither the form of the follower in conformation to the piston nor yet the form
of the overlapping tongues of its segments, is of the essence of the invention.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what i
claim is :-
1. The combination of a steam or other fluid cylinder, a piston adapted to said
cylinder, and a follower made in segments adapted to the circumferential portion of
said piston and applicable thereto and removable therefrom in the direction of the
length of the cylinder, substantially as described.
2. In combination with a piston, a circumscribing packing, and a removably
applied follower made in segments and by segments radially adjustable with respect
to the body of the piston, substantially as described.
3. In combination with a piston, a removably applied follower made in segments
and by segments radially adjustable with respect to the body of the piston, substan-
tially as described.
4. In combination with a piston, a removably applied follower made in segments
the meeting ends of which are provided with overlapping tongues, and means for

page_text: effecting the radial adjustment of the segments with respect to the body of the piston,
substantially as set forth.
5. In combination with a piston, a circumscribing packing, a removably applied
follower made in segments the meeting ends of which are provided with overlapping
tongues, and means for effecting the radial adjustment of the segments with respect
to the body of the piston, substantially as set forth.
6. In combination with a piston, a removably applied follower made in segments,
and key plates, constructed and applied as set forth and secured by key plate bolts,
for gauging the set of the segments of the follower in given positions of radial
adjustment, substantially as set forth.
Dated this Twenty-eighth day of January 1890.