Year: 1887

page_text: Date of Application, 4th Oct., 1887
Complete Specification Left, 4th July, 1888
Complete Specification Accepted, 4th Oct., 1888
I, JOHN GREEVES FISHER of St. Columba Street Woodhouse Lane Leeds in the
County of York Oil Merchant do hereby declare the nature of this invention to bo
as follows:-
This invention relates to that class of lubricator used for supplying a lubricant-of
a viscid or semi-solid consistance-to journals or bearings or other rotating or moving
parts of machinery.
Lubricators of this class have been made with a cap internally screwed to fit over a
solid and fixed plug forming part of or attached to the bearing. The cap receives and
contains the lubricant which is supplied to the bearing by the direct action of the
internally screwed cap, which forces it through a small orifice as it is screwed down
over the solid plug, and when the screwing action is discontinued the flow of the
lubricant ceases until the attendant again applies or turns the screw. Other lubri-
cators have been designed in which a solid piston or plunger fitting into a cup
containing the lubricant has been forced down by a screw, or gradually by a dead
weight or spring or by a spring acting upon a screw to turn it round slowly.
The object of the present invention is to provide a lubricator of the class
referred to which will have the advantage of imparting a direct pressure to the
lubricant for a time after it has been compressed or screwed together by the
attendant.
It consists essentially of a cup to contain the lubricant to be attached to or
carried by the bearing or journal and a hollow plug with a chamber for an air or
metallic spring. The two fit closely so that when drawn or forced together the
spring in the chamber of the plug is compressed between it and the lubricant, and
then the pressure of the spring acting on the lubricant forces it out to the
bearing.
In carrying out the invention I provide a cup made of any suitable material such as
cast iron, brass, glass, or the like with a projecting shank or other means for attaching

page_text: to or connecting it with the bearing or journal and a hollow plug or plunger of
similar material which fits closely into the lubricant containing cup. The cup is
fitted preferably with an internal or female screw and the hollow plug with a male
screw which engages with the screw of the cup and by turning the plug the two are
drawn together.
In the chamber or hollow in the plug a spring is placed which when compressed
acts upon the lubricant in the cup to force it out. This spring may be constructed in
several ways. A spiral metallic spring may be inserted to act upon a movable piston
or plunger or the air contained in the chamber may be compressed to act as
a spring. The chamber may be left open in the mouth and the air allowed to act
direct upon the grease in the cup or a diaphragm or piston may be inserted upon
which the air will act. The air may be enclosed within a series of diaphragms such
as are seen in an aneroid barometer the outer one acting upon the grease. In this
case the space enclosed by the several diaphragms will be filled with air at a normal
pressure which when pressure was exerted upon it would be compressed and form a
spring no visible means of escape being provided. The metallic spring and the air
spring may be combined in one apparatus. The apparatus may be made with a steady
pin projecting through the top which will also act as an index finger to indicate the
amount of compression of the spring and the consequent pressure. The screwing
of the two parts together compresses the spring (whether air or metallic) which as it
expands acts to force the lubricant out of the cup to the bearing or journal. A
continous action is thereby obtained extending over a considerable period of time
after it has been attended to. If found desirable the hollow plug may be fitted at or
near its mouth with a plunger or flexible diaphragm behind which the pressure of
the spring whether air or metallic-would be exerted.
In designing and making the lubricators the hollow chamber of the plug will be
constructed in proportion to the size of the grease cup as far as practicable to hold a
spring of the size or the quantity of air best adapted when compressed to give a
continuous elastic pressure for a length of time.
The circumstances under which the lubricators are used cannot always be the same
and when an air spring is used it may be found necessary to be able to alter the
capacity of the air chamber, for this purpose the air chamber may be made double,
that is with a second chamber screwing down into the first mentioned one or with an
additional receiver of any convenient shape to attach to the chamber either by
screwing into it or otherwise. When it is intended to increase the air capacity
of the chamber the additional receiver or second chamber is attached so as to open
into or communicate with the first chamber and when to decrease the capacity of
the chamber the second one is reversed or attached inside so as to fully or partially
fill up the air space and thus an amount of air to give the required elasticity of
pressure may be regulated. A small cap or other covering may be used to prevent
entrance of dirt to any nozzle or opening that might be left exposed.
It will be obvious that instead of serewing the walls of the cup and hollow plug
respectively a projecting screw may be fitted inside by means of which the cup and
hollow plug may be drawn together and a packing provided at their junction to
make a tight joint and prevent the escape of air.
Dated this 3rd day of October 1887
WM. P. THOMPSON & Co.,
6, Bank Street, Manchester,
Patent Agents.

page_text: the bearing, journal or other surface to be lubricated. B is a hollow plug or plunger
of material similar to any of those specified for the cup A which fits and screws.
closely into the cavity of the lubricant cup A. The cup A is formed with an internal
or female screw thread a and the hollow plunger with a male screw b which engages
with the screw a of the cup A and by turning the plunger B it is screwed or forced
into the cup A.
The interior or chamber of the hollow plunger B forms the containing chamber
for the spring buffer. A spring D is placed within the chamber C which when
compressed acts upon a diaphragm or piston E, placed in the mouth of the
chamber.
The spring may be constructed in several ways. I prefer the spiral metallic
spring D shown in Fig. 2. When compressed the spring acts upon the inner surface
of the piston E, the piston being packed in the chamber so as to move freely without
allowing the lubricant to leak or escape into it.
Instead of a metallic spring the air in the chamber C may be utilized as a spring
either acting directly on the piston which would be similarly packed or the air may be
enclosed within a compressible case D', formed of a series of diaphragms d, as shown
in Fig. 7, the outer one acting as a piston upon the lubricant. The compression of
the air in the case, by the screwing down of the hollow plunger B, will form a spring
buffer to force out the lubricant.
To the piston E may be attached a steady pin or spindle e which projects up through
the top of the hollow plunger B, and is at the outside fitted with a knob or screw nut G
by means of which the position of the piston can be slightly altered. The spindle e
and knob or nut G serve as an index finger to indicate the position of the piston, and
the amount of compression of the spring, and the consequent pressure exerted on the
lubricant.
In operation the cup A is filled with the lubricant, the spring and piston having
been previously adjusted in the hollow plunger B, to form the buffer, it is screwed a
greater or less distance into the cup. The action of screwing in the hollow plunger B
presses the piston E against the surface of the lubricant which forces it back into the
chamber compressing the spring D. The amount or intensity of the compression of
the spring depends on the distance the plunger B is screwed into the cup A and it is
regulated at will according to the length of time during which the lubricator is
required to operate without further attention. The pressure of the piston on the
lubricant gradually expels it through the passage H in the bottom of the
cup A.
Instead of screwing the walls of the cup and hollow plug respectively a screw
projecting from the bottom of the cup A may take the place of the spindle e, by
means of which the cup and hollow plug could be drawn together and a packing
provided at their junction to make a tight joint but I prefer the arrangement
described and shown in the drawings as best.
It will be obvious that instead of forming the chamber of the spring buffer in a
hollow plunger screwed into the internal cavity of the lubricant cup it may be formed
in the lubricant cup with a solid plunger fitting therein and in either case the
lubricant cup or the plunger may connect with the surface or part to be lubricated.
In Fig. 4 the spring buffer is fitted in the chamber C at the back of the lubricant
cup A¹, the plunger B being solid and forming the connection between the lubricator
and the surface to be lubricated. The screwing together of the parts compresses the
lubricant and the spring D of the buffer which then acts gradually to expel the
lubricant.
In Fig. 5 the spring buffer is fitted in the chamber C in the same casting with
the lubricant cup A" and forms the connection between the lubricator and the surface
to be lubricated. Beneath the spring D is fitted a secondary piston I which prevents
the lubricant passing into the chamber C. The pistons E and I may be made in
one piece with the channel H" through which the lubricant is expelled. The plunger Bu
when screwed down into the cup A compresses the spring D of the buffer. The
bottom coil of the spring bears against the back of the chamber C¹¹.

page_text: In Fig. 6 the arrangement shown in Fig. 2 is reversed, the plunger B₁ with the
chamber (being stationary and the lubricant cup A loose and screwed over the
plunger. The spring is placed as in Fig 5 with a secondary piston I below to prevent
the backward passage of the lubricant when passed through the channel H. a' is a
lug or pin to prevent the spring buffer leaving its chamber.
Instead of the metallic spring D or air spring D¹ the spring buffer may be formed
of indiarubber or other elastic material placed in a chamber in the lubricant cup or in
the plunger but such would not be durable and I do not recommend it.
It will be seen that the spring buffer may be compressed much or little as may be
required, the pressure being renewed from time to time by screwing the parts together
and when not in use all pressure upon the lubricant may be removed. When the
plunger is at any time screwed further into the cavity of the lubricant cup to diminish
its internal capacity the pressure does not wholly expend itself in immediately expelling
from the lubricator a quantity of the lubricant equal in bulk to the diminution
produced in the space within the cup by the act of so screwing in the plunger but this
pressure is for the greater part occupied in compressing the buffer which in turn
reacts continuously upon the lubricant expelling it gradually from the lubricator to the
rubbing or sliding surface or part of the machinery requiring to be lubricated and to
which the interior of the lubricator communicates in the ordinary way. This renders
my improved lubricator better, and much more serviceable than those that have no
spring, where lubrication is consequently wholly dependent upon the constant care of
the attendant, or than those in which a spring is fully compressed against the cap or
top of the cup when filled, where waste goes on while the machinery is at rest and
lubrication though at first perhaps in excess of the requirement diminishes or fails
after a portion of the grease has been consumed.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed, I wish it to be under-
stood that I do not claim a lubricator in which a piston is closely fitted into and
works in the lubricant cup itself, nor broadly the use of a spring and piston therein
to expel the lubricant as such have I am aware been already in use but I declare that
what claim is :-
1. In a lubricator the use of a spring buffer placed in a separate chamber or cell
communicating with the cavity of the lubricant cup to moderate, maintain and
prolong upon the lubricant the pressure produced by means of the screw connecting
the parts of the lubricator together substantially as described.
2. A lubricator having a hollow plunger fitted with compressible spring and
piston in combination with a cup or chamber to contain the lubricant into which it is
screwed, the lubricant being compressed between the piston of the plunger and the
bottom of the cup and expelled by the pressure exerted by the spring substantially as
described.
3. A lubricator having a cup A to hold the lubricant and a hollow plunger B
with compressible spring D or its equivalent and piston E to exert a continuous
pressure on the lubricant with or without the steady pin or spindle e acting as an
index finger substantially as described and shown.
4. A lubricator having a spring buffer, a chamber to contain said buffer, and a
lubricant cup in communication therewith constructed and arranged substantially as
described and shown in Figs. 2. 4. 5 or 6.