Improvements in or relating to Lathes and similar Machine Tools operated by Fluid Pressure.
Year: 1899

page_text: Date of Application, 21st Nov., 1899-Accepted, 3rd Mar., 1900
COMPLETE SPECIFICATION.
Improvements in or relating to Lathes and similar Machine Tools
operated by Fluid Pressure.
1, JAMES HARTNESS, of Springfield, in the County of Windsor, State of Vermont,
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 :-
This invention has relation to fluid-operated machine tools such as lathes, and while
designed particularly for use on turret-lathes, yet it may be equally well employed in
connection with other similar machine tools wherein an element is moved by fluid
pressure.
Heretofore, it has been attempted to feed the tool-holder in either of two different
ways; one way being by means of liquid pressure and the other being by elastic-fluid
pressure such as that produced by steam, gas or air. Where liquid is used, however,
it is more or less difficult to control, especially in large shops where a large number
of machines are operated, the liquid being frequently wasted and being liable to
freeze in cold weather; and, on the other hand, where elastic-fluid or air pressure is
used, although the air can be conducted quite easily to the machines and is easily
controlled, yet the tool-holder is fed unevenly, is caused to move with jerks, and
frequently causes breakage of the parts to such an extent as to practically prevent
the use of compressed air.
This invention comprehends the employment of both elastic and inelastic fluids,
whereby I am enabled to obtain the advantages due to the use of compressed air,
which can be distributed to various parts of the shop, and am also enabled to gain the
benefits due to the use of liquid.
The invention consists in a lathe or similar machine tool possessing certain features
of construction and relative arrangement of parts, all as illustrated upon the drawings,
now to be described in the accompanying Specification, and particularly pointed out
in the claims hereunto appended.
Reference is to be had to the annexed drawings and to the letters and figures
marked thereon, forming a part of this Specification, the same letters designating the
same parts or features, as the case may be, wherever they occur.
Of the drawings:
-
Figure 1 represents in side elevation the front end of a lathe embodying my
invention.
Fig. 2 represents a plan view of the same, partially in section.
Fig. 3 represents an end view of a portion of the bed of the tool-holder.
Fig. 4 represents a side elevation, partially in section, the parts being somewhat
enlarged to show the paths of the fluids.
Figs. 5 and 6 represent sections through the valve, the two views being drawn to a
different scale.
Fig. 7 represents a longitudinal section through the escapement device which I
employ for regulating the flow of the inelastic fluid to and from the cylinder.
J
.

page_text: Figs 89 and 10 represent transverse sections on the lines 8-8, 9-9, and 10-10,
respectively of Fig. 7.
Referring to the drawings:-
a indicates the bed of a lathe in which is mounted a sliding tool-holder b, and the
work-holder c. In the tool-holder or carriage is formed a cylinder d in which
there is a piston d¹, mounted upon the end of a piston-rod d², the other end of said
rod being rigidly secured to the end of the bed a, whereby, when fluid is admitted
to either side of the piston d¹, the carriage is moved towards or from the work, as the
case may be.
The port e leads into one end of the cylinder & on one side of the piston d¹ and
the port e leads into the port on the other side of the piston </¹.
findicates an escapement or regulating device for the fluid, and its object is to
regulate the flow of liquid which passes through it.
The port el is connected by a pipe g, a flexible hose g¹ and a pipe g² with one part
of the escapement while the other portion of the escapement is connected by a
pipe 2, a flexible hose h¹, and a pipe h, with the lower portion of a tank or reservoir i,
which is supported by the carriage or tool-holder b and travels with it. As shown, in
Fig. 3, the tank is attached to a depending bracket i¹. The tank or reservoir
is air-tight and is adapted to be partially filled with inelastic fluid such as water
or oil.
There is a by-pass h³ between the pipe h and the pipe 9, so that instead of the fluid
passing through the escapement f, it may pass directly from one pipe to the other.
A valve in the by-pass closes it, when it is desired to have the fluid pass through
the escapement or regulating device f.
is a pipe which leads into the top of the reservoir and which communicates with
a four-way valve, said valve consisting of a casing ¹, and a rotatable valve-
member k, as shown in Figs. 4 and 6. Said valve casing has a discharge-port 1³, an
inlet leading into a pipe le, and a port which leads into a pipe whose end is con-
nected to the port e. When the valve member 2 is in the position shown in Fig. 4,
it opens communication between the pipes 4 and 5 and the pipe k and the discharge-
aperture 3. The pipe communicates by a flexible hose with a pipe 7, leading
from a suitable air-pump, (not shown,) so that by turning the valve member into the
position shown in Fig. 6, or in Fig. 4, air may be forced either into the tank i or into
the rear end of the cylinder d, as the case may be.
The valve-member 2 is connected to a valve-stems from which extends a handle k³,
said stem being passed through a cap ¹¹.
Referring to Figs. 7 to 10, inclusive, it will be seen that the escapement or device
for regulating the supply of inelastic fluid to and from the cylinder consists of a
casing f, having therein a slide-valve f2 connected by a link f³ with a crank f*
projecting outwardly from a disk f on the end of a shaft which is mounted in the
headstock and which rotates the chuck. The main supply pipe 2 leads into a
chamber in the valve casing on one side of the valve, there being a similar
chamber on the other side of the valve. Extending inward from each of the
chambers are ports f7, f8, fo, f10, the ports f", f", registering with each other,
and the ports fs, f10 likewise registering with the other end of the chamber.
The valve is provided with two transverse ports f, f12, the former being
adapted to register with ports and ƒ and the latter with the ports f and f10
when the valve is at one or the other extreme of its movement, to permit the
passage of fluid from the main supply pipe to the cylinder or chamber f. The
valve 2 is also provided with a duct f13 to register with either of the ducts fo, f10,
to conduct the exhaust-liquid to the outlet g².
The chamber f is substantially cylindrical to receive a loose piston f¹ which is
reciprocated by the fluid as the valve f2 is moved forward and back. The piston
and cylinder act as a measuring device or meter to limit the amount of fluid which
passes through the casing independently of the initial pressure in the supply pipe
and the working resistance at the main cylinder. The volume of fluid may be
increased or decreased by limiting the movement of the piston f¹, this being

page_text: accomplished by the screw-stud 15 at one end of the cylinder and the pin f17 on
the rack f18 at the other end of the cylinder. This rack may be moved by the
partial pinion 19 on the shaft f20 said shaft being provided with a handle (not
shown) by which it may be rotated.
The operation of the apparatus is as follows:
When it is desired to feed the tool-holder forward or towards the work, the
valve member is thrown to the position shown in Fig. 6, and the air is
conducted through the pipes into the upper portion of the tank or
reservoir i. This forces the liquid in the tank through the pipe, hose h³,
pipe 2, escapement, pipe 92, hose 1, and pipe into the forward end of the
cylinder d.
The flow of the liquid is regulated by the escapement so that the carriage is
fed at any speed as may be desired, it being usually necessary to advance the
carriage slowly towards the work when the tool is in engagement therewith. To
return the carriage to its original stopping-point, the valve h¹, is opened, and
the valve member 2, is turned to the position shown in Fig. 4 to permit the air
to pass from the pipe to the pipe, into the rear end of the cylinder. As the
carriage moves rapidly backward, the liquid is forced out of the front end of the
cylinder through the port and the pipe g, the by-pass ³, and the pipe h, into
the lower end of the tank.
Thus it will be seen that I am enabled to use a small quantity of liquid such as oil
(which will not freeze) over and over again without any of it being wasted or escaping,
and at the same time, I am enabled to conduct the air from distant points to the
machine without difficulty and to easily control it. The elastic fluid forces the tool-
holder in both directions, by reason of its being deflected into the tank and cylinder
alternately, and the inelastic fluid governs the movement of the holder, and causes it
to be fed smoothly and evenly. I have contemplated duplicating the inelastic fluid
mechanism, though for general purposes such a duplication is unnecessary.
I have shown the controlling valve and the tank or reservoir as moving with the
carriage, but it will be readily understood that they may be supported upon the bed
and connected to the carriage by flexible hose pipes, if desired.
Many other changes may be made in the apparatus shown without departing from
the spirit and scope 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. A fluid-operated mechanism, comprising a piston and cylinder, of which
elements one is movable relatively to the other, means including a receptacle for
delivering inelastic fluid into the cylinder to move the movable element in one
direction, and means for delivering elastic fluid into the receptacle or into the
cylinder, whereby said element is moved in either direction by elastic fluid pressure
and is controlled or governed by inelastic fluid.
2. A fluid-operated mechanism comprising a piston and cylinder, of which elements
one is movable relatively to the other, and means for forcing the movable element in
both directions alternately by elastic fluid pressure, including a tank interposed
between the sources of elastic fluid supply and the cylinder, and containing inelastic
fluid, whereby said inelastic fluid controls or governs the movement of the movable
element, and devices for conducting elastic fluid into said tank or to said
cylinder.
3. A fluid-operated mechanism comprising a piston and cylinder, of which elements
one is movable relatively to the other, a tank or reservoir for an inelastic fluid
communicating with the cylinder on one side of said piston, a pipe leading from. a
source of elastic fluid supply, and a valve mechanism for opening a communication
alternately between said pipe and said tank and said pipe and said cylinder on the
other side of said piston.
4. A fluid-operated mechanism comprising a piston and cylinder, of which elements

page_text: one is movable relatively to the other, means for forcing the movable element in both
directions by elastic fluid pressure, a tank interposed between the source of elastic
fluid supply and the cylinder, and containing inelastic fluid, whereby said inelastic
fluid controls or governs the movement of the movable element, devices for con-
ducting elastic fluid into said tank or to said cylinder, and an escapement interposed
between the tank and the cylinder to control the flow of the inelastic fluid.
5. A fluid-operated mechanism comprising a piston and cylinder of which eleinents
one is movable relatively to the other, means for delivering inelastic fluid into one
end of said cylinder to move the said element in one direction, means for delivering
an elastic fluid into the other end of said cylinder to move said element in the
opposite direction, and an escapement for controlling the passage of said inelastic
fluid into or out of the said cylinders.
6. A fluid-operated mechanism comprising a piston and cylinder of which elements
one is movable relatively to the other, a tank or receptacle for an inelastic fluid, a
conduit leading from the lower portion of said tank or receptacle to one end of said
cylinder, a conduit leading from the upper portion of said tank or receptacle to the
other end of said cylinder, and means for supplying elastic fluid to the tank to force
the inelastic fluid into the cylinder or to the last-mentioned end of said cylinder to
force the inelastic fluid back into the tank.
7. A fluid-operated mechanism comprising a piston and cylinder of which elements
one is movable relatively to the other, a liquid tank or receptacle, a conduit leading from
the lower portion of said tank or receptacle to one end of said cylinder, a valve-casing
communicating with said tank or receptacle and with the other end of said cylinder,
a conduit for conducting compressed air to said casing, and a valve in said casing for
deflecting the air into the tank or into the cylinder.
8. A lathe comprising a tool-holder, a piston and cylinder for moving said holder,
a tank or receptacle for inelastic fluid communicating with one end of said cylinder,
a suitable source of elastic fluid supply, a pipe leading into the other end of said
cylinder, and means for conducting elastic fluid into said tank or receptacle or into
said cylinder.
9. A fluid operated mechanism comprising a piston and cylinder, of which
elements one is movable relatively to the other, means including a receptacle com-
municating with said cylinder and adapted to contain a body of inelastic fluid, and
means including a source of elastic fluid supply and conduits leading therefrom to
the cylinder and the receptacle for forcing the inelastic fluid from the receptacle into
the cylinder or from the cylinder into the receptacle.
10. A lathe comprising a tool-holder and means for moving said holder, said means
comprising a piston and cylinder, a liquid tank, a conduit between said tank and one
end of said cylinder, a liquid escapement between the tank and the cylinder, a
conduit between said tank and the other end of said cylinder, a four-way valve in
said conduit, and a compressed-air-pipe leading to said valve, said parts being
constructed and arranged whereby elastic fluid is conducted to the tank or to the
cylinder, and the inelastic fluid is conducted into the cylinder from the tank or from
the cylinder into the tank.
JAMES HARTNESS.
Haseltine, Lake & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicant.