Improvements in Rotary Motors and Pumps.
Year: 1893

page_text: Date of Application, 11th Apr., 1893-Accepted, 17th June, 1893
COMPLETE SPECIFICATION.
Improvements in Rotary Motors and Pumps.
I, JAMES YATE JOHNSON of 47 Lincolns Inn Fields in the County of
Middlesex Gentleman do hereby declare the nature of this invention (which has
been communicated to me from abroad by Frank Henry Cathcart of 2002 North
31st Street in the City of Philadelphia State of Pennsylvania in the United States
of America Mechanical Engineer) and in what manner the same is to be
performed to be particularly described and ascertained in and by the following
statement:-
This invention relates to rotary motors and pumps and 1 will describe the
improvements constituting the present invention (as applied to a motor) with
reference to the accompanying drawings wherein
Figure 1 is a sectional elevation of a motor constructed in accordance with this
invention;
Figure 2 is a central section at right angles to Figure 1 of the same shewing the
rotary part of the motor in a different position.
Figure 3 is a transverse vertical section (the section being taken on the line 1, 2
Figure 4) shewing a modified construction;
Figure 4 is a vertical section at right angles to Figure 3 (the section being taken
on the line 3, 4 Figure 3).
Figure 5 is a sectional plan view (the section being taken on the line 5, 6
Figure 6) of a form of piston blade shewing packing which may be employed; and
Figure 6 is a transverse section of the same (the section being taken on the
line 7, 8 Figure 5).
Figure 7 is a sectional elevation of the piston of the motor detached from the
casing.
Figures 8 to 17 inclusive, are perspective views illustrating the essential parts of
the piston detached from each other.
Figure 18 is a detached perspective view of a detail.
The casing a is formed in two sections for convenience of manufacture and fitting
the parts together and in the said casing is formed a cylinder or chamber b.
Capable of being rotated within the chamber on an axis eccentric to the centre
of the chamber, is a piston body of a construction more clearly shewn in Figures ī
and 8 to 17 and comprising two main sections 623 which, when placed together,
form a spool-like body reduced in diameter at the centre and having opposite end
flanges e tapering in cross section from the centre to the outer edge. These two
sections 2 and 3 are held a sufficient distance apart to permit of the entrance of
the sliding piston blades d d² and the longitudinally adjustable wedge block d³ the
three parts d d and d³ forming a diametral piston which slides to and fro between
the parts 23 under the control of the inner periphery of the chamber so that
the outer edges of the blades d d² are at all times in contact with the periphery of
that portion of the chamber 6 in which the blades and the reduced central portion
of the piston body operate, while the end portions in which the tapered flanges
are placed is circular in form, its centre being coincident with the centre of
rotation of the piston body. The two sections 623 are held apart by spacing
blocks or strips e e² e (Figures 15, 16 and 17) placed at the extreme end of the
piston body and these spacing blocks or strips are preferably of cross-like form in
transverse section having spacing ribs e of a slightly greater height than the
thickness of the piston blades so that the piston blades may slide freely to and fro
as dictated by the eccentric chamber b. At right angles to the ribs e¹ are ribs e
which are adapted to the slots 6 in the opposite ends of the sections 62,³ the
ribs e entering the slots 6 and keeping the parts in proper position and at the
C

page_text: same time preventing the escape of the operating fluid used as a motive power for
the engine.
The opposite ends of the sections 13 13 are provided with screw threads on
shoulders projecting from the ends of the sections and slightly less in diameter
than the diameter of the flanges c and connecting the two sections together are end
discs ff (Figures 7, 12 and 13) having projecting flanges adapted to the threaded
shoulders 6 and the whole forming, when in position, a compact structure which
rotates on journals preferably formed integral with the discs, the disc f being
provided with a journal 3 adapted to a bearing box a² on the casing and between
the box and the journal 3 is a bushing of suitable antifriction metal, which is
perforated to admit a supply of lubricant to the bearing, the latter being provided
with a chamber which is constantly kept filled with lubricant from an oil cup h.
This bearing box a² is formed integral with a head a³ screwed to the casing a so
that it may be removed when necessary for the parts to be examined or repaired.
The opposite head 2 is also provided with a journal or shaft i adapted to a similar
bearing a supplied with lubricant by an oil cup h² and on this end of the casing a
is a head a similar to the head a³.
g
The journal 3 is hollow and contains a circular stem suitably shaped at its
inner end and adapted to fit under the wedge shaped adjusting block d³ one side
of which is provided with a transverse groove d to which is adapted a tongue j
projecting from a piece of hardened metal which is provided with what may be
termed a circular dovetailed projection adapted to a suitably shaped recess f³
(see Figure 11) in the stem so that when these two parts are in proper position
any longitudinal displacement will be effectually prevented while lateral displace-
ment is guarded against by fitting the joined ends of the parts within a recess b
formed partly in the portion 62 and partly in the portion 63, the main body of the
stem however, being contained within the hollow journal f3 and being provided
with a threaded stem and a squared end 7 (see Figure 7) to which a key may
be applied when adjusting the nut 4, to which the threaded stem is adapted.
This mut has a Hange k² against which presses a gland nut adapted to the
threaded opening in the journal f³ and between the flange k² and a ring m, which
fits against the shoulder in the journal, packing a is inserted which effectually
prevents the escape of any of the actuating fluid.
By the use of these adjusting devices the wedge block d³ may be moved
longitudinally against the inner inclined edges of the piston blades d and d² to force
the said blades out a greater or less distance to compensate for the increased
diameter of the chamber as it wears by the friction of the blades, and the wedge
block, sliding to and fro, is at all times under the control of the adjusting stem f* and
at any time, or in any position, may be adjusted to any desired extent.
At that portion of the chamber b where the piston blade is caused to descend
wholly within the space between the portions 6 and 63 is placed, what may be
termed, a fixed abutment p (Figures 1 and 18) made of a separate piece of hardened
metal and so arranged as to correspond exactly to the contour of the piston body,
the tapered flanges e being inclined at the most suitable angle for automatically
taking up any wear which may occur and with a view to having all portions of the
fixed abutment exposed to the same, or nearly the same, amount of wearing friction.
This abutment may be fixed if desired, but preferably, to avoid uneven wear, a
spring or springs is or are placed at the back of the abutment which tends or
tend to move the abutment in a radial line towards the centre of rotation of the
piston body so as to insure, at all times, a perfect contact with the periphery of the
latter.
The advantages resulting from the use of a chamber in the form shewn will be
readily apparent, the even and regular wear of the inner periphery of the chamber
and the gradually increasing space allowing the expansion of the actuating fluid,
being advantages of the greatest importance.
In engines of the rotary type hitherto constructed the piston blades have been
supported only at the inner edge and the ends of the piston being exposed to a

page_text: frictional contact with the inner surfaces of the cylinder heads soon wore the ends
of the chamber and the ends of the piston blades to such an extent as to permit the
passage of fluid from one side of the piston to the other, this uneven wearing being
due, for the most part, to the fact that the extreme outer edge of the piston travels
a greater distance than does the inner edge.
This difficulty is avoided in the use of a piston such as I have describel as in
this case the opposite ends of the blades are supported by the flanges e and the
inner edges are supported by the main piston body, so that no portion of the piston
blade is exposed, to any great extent, to wearing friction excepting its outer edge
and this is compensated for by the employment of the adjusting block d³.
In some instances it may be desirable to pack the piston blades to prevent the
passage of steam or other fluid from one side of the piston to the other, and this is
accomplished by recessing the blades and placing in such recesses L-shaped
strips and s which overlap each other so as to form break joints and which are
forced out from the recesses by compression springs t as shewn in Figures 5 and 6.
In operation the fluid under pressure is admitted through the port its flow
being governed by a valve v under the control of a hand wheel w (see Figure 1)
and the fluid being exhausted after operating upon the piston blades through the
channel or passage a.
In Figures 3 and 4 which represent modifications of the said motor the piston
blades d d are held apart by fluid under pressure entering through a pipe y which
communicates with the main supply and the wedge adjusting block may, in this
event, be dispensed with.
I do not limit myself to the precise details of construction of the motor as it will
be evident that they may be varied without departing from the nature of this
invention.
The motor constructed as herein before described may be used for any purpose to
which it is, or may be, applicable. It is, for instance, well adapted for use for
driving a tool such as is described in the Specification of the Application for
Letters Patent No. 6562 made by my foreign correspondent on the 28th March
1893.
It will be evident that the apparatus can be used as a pump for pumping water
or other fluids if the piston be driven the inlet constituting the suction and the
exhaust the outlet of the pump.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed I declare that what I
claim is:-
1. The combination of the two part piston body, threaded flanged ends on the
said piston body, spacing blocks between the two parts adapted to hold the same in
proper position, threaded discs adapted to the said threaded flanged ends, journals
on the said dises and piston blades carried by the said piston body, substantially as
herein before described.
2. The combination of the two part piston body, recesses in the adjoining faces
of the two parts spacing blocks adapted to such recesses, and opposite end discs
adapted to hold the parts of the piston body in position, with piston blades carried
by the said piston body, substantially as herein before described.
3. The combination of the two part piston body, recesses in the adjoining faces
of the two parts, spacing blocks of cross-like form in transverse section having ribs
adapted to such recesses and opposite end discs adapted to hold the parts of the
piston body in position, with piston blades carried by the said piston body,
substantially as herein before described.
4. The combination of the piston body, the radially sliding piston blades therein
the said blades having their inner edges inclined from each other, the wedge shaped
adjusting block between the said blades and adapted to slide radially therewith,
and devices for effecting the longitudinal adjustment of the said block, substantially
as hereinbefore described.

page_text: 5. The combination of the piston body, the radially adjustable blades therein,
the said blades having their inner faces inclined from each other, an adjustable
wedge shaped block between the said inclined faces, a longitudinal adjustable stem
and a projection on the said stem engaging with a transverse groove in the wedge
shaped block, substantially as herein before described.
6. The combination of the piston body, the radially adjustable blades therein,
the inner faces of the said blades being inclined from each other, the wedge shaped
adjusting block between such inclined faces and the longitudinally adjustable stem
having a dove-tailed recess, a block having a dove-tailed projection adapted to such
recess, and a projection on the said block adapted to a transverse groove in the
wedge shaped block, substantially as herein before described.
7. The combination of the piston body, the radially adjustable blades therein,
the said blades having their inner faces inclined from each other, the wedge shaped
adjusting block between such inclined faces, the adjustable stem, a threaded shank
thereon, an adjusting nut engaging with the said threaded shank and a gland nut,
substantially as hereinbefore described.
8. The combination of the piston body, the radially adjustable blades therein,
the wedge shaped adjusting block between such blades, the adjustable stem, a
threaded shank thereon, the adjusting nut carried thereby and having a flange,
gland nut, a ring and packing between said ring, and the adjusting nut, substantially
as hereinbefore described.
a
9. The arrangement and combination of parts constituting a rotary motor or
pump substantially as hereinbefore described and shewn in Figures 1 and 2 of the
accompanying drawings.
10. The arrangement and combination of parts constituting a rotary motor or
pump substantially as herein before described and shewn in Figures 4 and 5 of the
accompanying drawings.
Dik: 114, 1. of Al 10012
J. H. JOHNSON & Co.,
Agents.