An Improved Mechanism for Operating Pumps.
Year: 1895

page_text: Date of Application, 4th June, 1895-Accepted, 3rd Aug., 1895
COMPLETE SPECIFICATION.
An Improved Mechanism for Operating Pumps.
1, MEREDITH LEITCH of Richmond in the County of Henrico, and State of
Virginia, United States of America, Gentleman, 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:-
My invention relates to improvements in pumps with shifting eccentrics.
The invention has more particularly to do with steam boiler and water feed
pumps or other analogous water feeding devices and consists, 1st. in the com-
bination of an operating shaft, one or more eccentrics mounted thereon, devices for
increasing or decreasing the eccentricity of said eccentrics on said shaft, and
means for operating said devices and locking them in their adjusted positions,
2nd. in the combination of an operating shaft, one or more adjusting eccentrics
mounted thereon, operating eccentrics adapted to have their eccentricity increased
or decreased by said adjusting eccentrics, and means for locking them in any desired
position, 3rd. of the combination of an operating shaft adjusting eccentrics mounted
on the same, operating eccentrics connected to said adjusting eccentrics, means for
operating said adjusting eccentrics, and water feeding devices connected to said
eccentrics and operated thereby.
It also consists of certain other novel constructions, combinations and
arrangements of parts all of which will be hereinafter more particularly set
forth and claimed.
In the accompanying drawings forming part of this Specification,
Fig. 1. represents a central vertical, longitudinal section of the mechanism
embodying the invention;
Fig. 2. represents a side elevation partly broken away, of the two eccentrics,
the operating gearing, belt wheel, etc.;
Fig. 3. represents the same with one of the gear wheels omitted and a modified
form of connection between the balance wheel and the eccentric; and
Fig. 4. represents a side elevation of the two eccentrics one within the other;
Fig. 5. represents a central vertical section through a modified form of the
devices embodying my invention, one wedge and two pumps being used;
Fig. 6. represents a detail central vertical section through said modified devices
as constructed where two wedges and two pumps are employed;
Fig. 7. represents a detail end elevation of one of the eccentrics and its
guiding disks used in these modified forms;
Fig. 8. represents a central vertical section through the modified devices
embodying my invention as constructed when only one pump is to be operated;
Fig. 9. represents an end elevation of the same;
Fig. 10. represents a top plau view of the same;
Fig. 11. represents a detail central vertical section through the valves in
communication with the said single pump of this modified form ;
Fig. 12. represents a side elevation of the disk and spring actuated catch by
means of which the wedge operating screw of said modified forms are turned and
fixed in any desired position; and
Fig. 13. represents a central vertical section through the shaft, wedge and wedge
operating nut of said modified forms.
A in the drawings represents the base of the apparatus. This base is provided
at each end with hollow upright standards a in the upper ends of which are formed

page_text: journal boxes a' in which a hollow operating shaft B has its ends journaled;
suitable oil cups a² being provided in said journal boxes.
The said shaft B is provided with a fly or belt wheel cast integral therewith
and transmitting the power from any suitable source to said shaft. Adjusting
eccentrics C are loosely mounted on said shaft upon opposite sides of the belt
wheel and are respectively confined against longitudinal movement in an outward
direction by collars 6 secured to said shaft by set screws b².
Each of the adjusting eccentrics is provided upon its inner face with an
annulus C¹ whose centre is the shaft B. Each annulus is provided upon its inner
circle with rack teeth, thus forming an annular rack on the inner side of each adjusting
eccentric by means of which said eccentric may be revolved. The shaft Bas
before stated, is hollow to accommodate an eccentric actuating rod D which
passes through the entire length of the shaft.
One end of this rod is mounted in a block d by means of a bolt d' and securing
nut and the opposite end passes loosely through the hub d³ of a disk d. Said
hub is keyed rigidly to the shaft B and the disk is notched about its periphery as
at d. A disk E is rigidly secured to this end of the rod by a bolt e and is provided
with an operating handle el having a catch e² pivoted therein and held in it's normal
. position engaging any one of said notches d³ by a pronged spring e³. The end of
the catch works through an aperture in said disk E and is adapted to engage any
one of the notches cut in the periphery of the disk' and 'thus 'the said disk E and
the rod D may be turned independently of the shaft B and then locked to the same
so as to rotate therewith.
The rod D. is provided near its middle with two annular rows of longitudinal
grooves or depressions into which cog wheels f, fare adapted to mesb
respectively; said wheels passing through slots in shaft B. The wheels f, f,
are each journaled on pins which are rigidly mounted in projections f³, få
of the shaft B. The hubs of each of the wheels f, f, are extended and provided
with cog teeth f³, f3 adapted to mesh 'with the annular racks C¹.
It will thus be seen that the adjusting eccentrics C may be turned on the shaft
to any desired. position and locked in such position. The eccentrics C, C, are
preferably so arranged and connected to the gears that they will always be
diametrically opposite to each other in eccentricity no matter how they are adjusted.
But if so desired the rod D may be made in two parts and a disk and locking
mechanism.applied on the ends so that the eccentrics may be adjusted independently
of each other.
Operating eccentrics H surround the eccentrics C peripherally and are each
provided with a peripheral strap retaining flange or bead . These 'eccentrics
are loosely mounted upon the adjusting eccentrics and are each connected to the
shaft B by a slotted arm I formed integral with the shaft B. These arms extend
radially from the shaft near its middle and at diametrically opposite sides and are
each provided with an angular slotted end i adapted to receive a pid secured to
the operating eccentric and thus said eccentrics are caused to revolve with the
shaft B but can move laterally thereto when they are being adjusted because of
said pin and slot connection. In lieu of this slot and pin connection, I have shown
in Fig. 3 the belt wheel connected to one of the eccentrics by an angular segmental
link which has one of its ends pivotally attached to a spoke of the belt wheel by
a bolt and nut k¹, k² and its opposite end secured in a similar manner to the
eccentric H.
An eccentric strap L provided with an annular groove is secured 'about each
eccentric by its lugs, being secured together by a bolt 2, the groove / fitting
over the flange or bead h and thus securing the strap against lateral displacement.
Each strap is provided upon its under side with a nipple within which the upper
end of a plunger rod M is secured so that as said eccentrics revolve the rods are
alternately raised or lowered.
'
Pistons or plungers N are connected to the lower ends of said rods and are
composed of cylinders N' having heads n' at their lower ends; said heads closing

page_text: said ends. These piston cylinders are adapted to operate in cylinder casings
which are preferably cast integral with the base A. The inner surface of each of
these casings is provided with an annular ledge o which forms a seat for supporting
the packing O' which is forced against the piston cylinder to make a water tight
joint by means of collars o'.
Water inlet and outlet ports p, p¹ are provided in the lower part of each of the
casings. The water first enters an air chamber a³ in one of the supporting
standards a and is drawn from the same into the first pump and from this pump is
The
forced into an air chamber a formed in the other supporting standard a.
other pump acting in exactly the same manner but with an alternating action in
regard to the first mentioned pump, that is, one pump will be drawing water from
chamber a while the other is forcing water into the chamber a. Suitable valves
are provided in the passages leading to the inlets pl so that a backward flow of
water in said passage is prevented.
During the pumping operations, the chamber a³ acts as a vacuum chamber and
the chaniber a as an air compression chamber, and by means of these chambers a
steady feed of the water is secured.
It will be seen from the aforegoing description that the eccentricity of the
eccentrics may be increased or decreased at will by simply turning the handle as
in Fig. 1, which movement rotates the adjusting eccentrics in the operating
eccentrics and thus moves said eccentrics up or down, one moving up the exact
distance that the other moves down which causes the said eccentrics to always
stand in the same relative position to each other, with respect to their throw.
The greater the eccentricity of the eccentrics, the longer the strokes of the pumps
will be and the greater the volume of water fed, but as the eccentricity is decreased
by moving the adjusting eccentrics, the pumps move slower in proportion.until
they stop entirely when the eccentrics are adjusted to a concentric position on the
In the modified
shaft B, with the latter passing exactly through their centres.
forms of my invention as shown in Figs. 5 to 13 inclusive:
1 represents the base of the apparatus. This base is provided with hollow
upright standards 2 similar to standards a and in the upper ends of which are
formed journal boxes 2" in which the hollow shaft 3 has its ends journaled.. This
shaft 3 is provided with a fly or belt wheel 4 cast integral therewith and trans-
mitting power from the main engine to said shaft. The shaft 3 as before stated
is hollow and is provided with a slot 3* through which the operating nut 5 mounted
on the screw threaded adjusting rod 5, is adapted to pass to engage the double
reversely inclined wedge'6.
The said rod 5ª has its screw threaded portion passed through the screw
threaded aperture in the nut 5 and thus when revolved moves said nut either
backward or forward according to the direction of the rotation. The rear end of
the rod is mounted in a block 7 set into the shaft 3 and the forward end passes
through a similar block"7* carrying a perforated disk 7 and is rigidly 'secured to
a disk 8 which overlaps the edges of the disk 7.
The disk 8 is provided with an operating handle 8 which has a catch 8b pivoted
thereto and 'held in its normal position by a spring 8° which is set in said handle.
The end of the catch works through an aperture in said disk 8, and is adapted to
engage any one of a 'series of apertures cut about the periphery of the disk 7b and
thus the said disk 8 may be 'turned into any desired position and locked to said
disk 7 which is rigid with the shaft 3, the screw.5° fastened to:said disk being
also operated and locked in the desired position and thereby the wedges also moved
and 'locked.
A pair of guiding disks 9, 19" is mounted rigidly on the shaft 3 for each
eccentric 10, 10'; said 'eccentrics 'being "confined respectively 'between said disks
but 'being capable of movement by reason of their slotted connection with said
disks. This slotted connection is formed by means of slots 11, 111 and 11ª.cut in
said eccentrics, bolts 12 passing through the slot 11, 11 and holding said guiding
disks'9; 9 in position.

page_text: The said guiding disks are also provided with slots 13, 13 through which the
adjusting wedges 6 pass. These wedges also pass through inclined slots 14 in the
eccentrics and thus as said wedges are moved backward and forward, the eccentricity
of the eccentrics is altered.
The lower portion of the wedge is composed of two oppositely inclined faces
which are adapted to work in the slots of the respective eccentrics. The upper
portion is composed of two adjustable wedge blocks 15, 15 having oppositely inclined
faces. These blocks are adjustable independent of each other by means of adjusting
screws 15 which pass through lugs on said blocks and engage a bar 16 having a
notch 17 within which the upper end of the nut 5 fits and thus moves said bar with
it back and forth and operates the wedges.
An eccentric strap 18 is passed about each eccentric and has a plunger rod 19
secured at its lowest point, so that as said eccentrics revolve, the rods are alternately
raised and lowered, and thus operate the pistons connected thereto. The straps
are secured about said eccentrics by suitable securing bolts. These pistons are
composed of cylinders 20 having blocks 20ª at their lower ends which close said
ends and thus form the piston.
These piston cylinders are adapted to operate in cylinder casings 21 which are
preferably cast integral with the base. The inner surface of each of these casings
is provided with an annular ledge 21" which forms a seat for supporting the
packing 22 which is forced against the piston cylinder to make a water tight joint
by means of collars 23. Water inlet and outlet ports 24 and 24ª are provided in
the lower ports of the casings.
The water first enters an air chamber 25 in one of the supporting standards 2
and is drawn from the same into the first pump and from this pump is forced into
an air chamber 26 formed in the other supporting standard 2. The other pump
acting in exactly the same manner but with an alternating action in regard to the
first mentioned pump, that is, one pump will be drawing water from chamber 25
while the other is forcing water into the chamber 26. Suitable valves are provided
in the passages leading to the inlets 24 so that a backward flow of water in said
passage is prevented.
During the pumping operations the chamber 25 acts as a vacuum chamber, and
the chamber 26 as an air compression chamber, and by means of these chambers a
steady feed of water is secured.
In the form or construction shown in Fig. 6 the wedges for operating or
adjusting the eccentrics are formed in four blocks or pieces 27, 28, 29, and 30
and the bar 31 is divided in the centre and the portion 27 attached to one-half by
means of the adjusting screw 32, and the portion 29 to the other half in a similar
manner.
In this form nuts 33 and 34 are employed, one being connected to the blocks 27
and 28 and the other to the blocks 29 and 30 by engaging recesses 35 formed
therein. The nut 34 passes through a slot 34 similar to 3ª and is mounted upon a
screw threaded sleeve 36 through which the rod 5" passes. The sleeve 36 is rigidly
secured in a hub 37 of a disk 38 which corresponds to the disk 8 at the opposite
end of the shaft. The said hub is adapted to turn loosely in said hollow shatt when
it is desired to rotate the screw threaded sleeve to move the nut 34 backward or
forward to operate the wedges 29 and 30. The disk 38 has an operating handle 39
similar to the handle 8ª. A disk 40 is attached to this end of the rod 5" and is
provided with notches or recesses 41 similar to the disk 7° and adapted to be engaged
by the spring catch of the handle 39.
It will be seen from the aforegoing that in the construction the eccentrics can be
adjusted to be more or less eccentric either together or separately. When it is
desired to adjust the eccentrics together the handle 8ª is turned, thus rotating
the rod 5 and the sleeve 36 together and the nuts 33 and 34 are thus moved
in unison and in the same direction according to the direction of the rotation of
the disk 8.
When it is desired to rotate either the rod 5" or the sleeve 36 independently,

page_text: the catch on the handle 39 is loosened from the disk 40 and the sleeve 36 alone is
rotated and thus only the wedges 29. and 30 are moved. If the disk 8 were rotated
while the catch on handle 39 is out of engagement with the disk 40 the rod 5* alone
would be rotated and thus only the wedges 29 and 28 moved.
In the construction shown in Figs. 8, 9, 10, and 11, only one pumping cylinder
and one operating eccentric, etc., are employed, but in all other respects this form is
substantially like that shown in Fig. 5. In Fig. 11 is shown at 42 a preferred
form of valves for preventing the backward How of water, but any ordinary
construction of valves may be substituted, therefor, as this does not form any part
of my invention.
'
It will be seen from the aforegoing description that the eccentricity of the
eccentrics may be increased or decreased at will by simply turning the handle,
which movement moves the oppositely inclined wedges back or forward in the slot
in the operating eccentrics and thus moves said eccentrics up or down one moving
up the exact distance that the other moves down which causes the said eccentrics
to always stand in the same relative position to each other with respect to their
throw.
The greater the eccentricity of the eccentrics, the faster the pumps will operate
and the greater the volume of water fed, but as the eccentricity is decreased by
moving the wedges the pumps move slower in proportion until they stop entirely
when the eccentrics are adjusted to a concentric position on the shaft 3 with the
latter passing exactly through their centres.
As the bearing surfaces between the wedges and the slots of the eccentrics
become worn the upper portions of the wedges can be moved up by the adjusting
screws (15) so as to make a perfect joint between said wedges and the eccentrics.
In the form shown in Fig. 6, the wedges can be moved in the eccentric independently
of one another and thus either one of the pumps can be made to operate while the
other is stationary, or one can be moving with a long full stroke while the other is
moving with a much shorter stroke, or vice versa.
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 an operating shaft, one or more eccentrics mounted thereon,.
devices for increasing or decreasing the eccentricity of said eccentrics on said shaft,
and means for operating said devices and locking them in their adjusted positions,
substantially as described.
2. The combination of an operating shaft, an adjusting eccentric loosely mounted
thereon, an operating eccentric mounted on said adjusting eccentric and adapted to
have its eccentricity increased or decreased by said adjusting eccentric, means
for operating said adjusting eccentric and positively locking it in the desired
position, and means connecting the operating eccentric with the shaft so that
it revolves therewith, but can move laterally independent of the same, substantially
as described.
3. In a feed water mechanism, the combination of an operating shaft one or more
adjustable eccentrics loosely mounted thereon, operating eccentrics mounted on said
adjusting eccentrics and adapted to have their eccentricity increased or decreased
by said adjusting eccentrics, means for operating said adjusting eccentrics, and water.
feeding devices connected to said eccentrics and operated thereby, substantially as
described.
4. The combination of an operating shaft, adjusting eccentrics mounted on the
same, operating eccentrics mounted on said adjusting eccentrics and connected to
the shaft to revolve therewith, gearing for operating said adjusting eccentrics and
devices mounted on the shaft for locking said gearing in the desired position,
substantially as described.
5. The combination of a hollow operating shaft, adjusting eccentrics mounted on.
the same, operating eccentrics mounted on said adjusting eccentrics, a rod loosely

page_text: mounted in said shaft, devices for operating said rod and gearing for imparting
the motion of said rod to said adjusting eccentrics, substantially as described.
6. The combination of a hollow operating shaft, adjusting eccentrics loosely
mounted upon the same and provided with annular racks, gears mounted on the
shaft and engaging said racks, means for operating said gears, operating eccentrics
mounted on said adjusting eccentrics and means for connecting said operating
eccentrics with the shaft so as to revolve therewith, substantially as described.
7. In a feed water pumping mechanism, the combination of an operating shaft
having radial slotted arms, adjusting eccentrics loosely mounted thereon, means
for operating said eccentrics and locking them in the adjusted position, operating
eccentrics mounted on said adjusting eccentrics, and having pins engaging said
slotted arms, straps about said eccentrics and feed water pumps connected to and
operated by said straps.
8. The combination with a hollow shaft, adjusting eccentrics mounted on the
same and provided with annular racks gears mounted on the shaft and respectively
engaging said racks, a rod in said shaft for operating said gears, devices for
operating said rod, and means for locking said rod to said shaft at will, substantially
as described.
9. The combination of an operating shaft having radial slotted arms adjusting
eccentrics loosely mounted on said shaft, means for operating said eccentrics, and
operating eccentrics mounted on said adjusting eccentrics and provided with pins
which engage said slotted arms, substantially as described.
Dated this 29th dow of Anvil 1905
MEREDITH LEITCH.
Wm. P. Thompson & Co.,
Of 6 Lord Street, Liverpool, Agents for the Applicant.