Improvements in Machinery for Grinding or Lapping Round Holes or Eyes.
Year: 1895

page_text: Date of Application, 12th Oct., 1895-Accepted, 16th Nov., 1895
COMPLETE SPECIFICATION.
Improvements in Machinery for Grinding or Lapping Round Holes
or Eyes.
I, HUGH REID, Engineer, of the Firm of Messrs. Neilson and Company,
Hydepark Locomotive Works, Springburn, in the County of the City of Glasgow,
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-for-its-object-to-provide a machine of improved construction
for grinding or lapping round holes such for example as the eyes of connecting-
rods after case hardening, the improved machine being designed to revolve or
otherwise traverse the work around a grinding tool secured on a rotating spindle.
In the accompanying drawings which illustrate the invention Figure is a
longitudinal vertical section and Figures 2 and 3 are respectively a front and back
elevation of the improved grinding or lapping machine.
The machine comprises a strong framing made up for convenience of a base
piece Z having mounted on it side cheeks Z' bound together and provided with
journal bearings for the several rotating shafts which actinte the working parts.
The work to be operated on is secured upon a table Q which is bolted to the
upper slide R of compound slides R, S, the rotating spindle A, upon which is
secured the emery or other grinding or buffing wheel A', being passed through
the eye or hole to be operated on. The table Q with the work is moved through
a circular path so as to revolve or traverse the inner periphery of the eye around
the grinding tool, whilst the latter is rotating in contact with it, by means of a
hollow piu or driver T engaging the slide R and fitted more or less eccentrically
on driving spindles U, Y, journaled in the base piece Z these spindles being in
line with the grinding or buffing spindle A.
The huff spindle A has a combined rotary and vertical reciprocating motion.
The rotary motion is conveyed to the spindle by bevelled friction gear B, C, driven
by belting from a main driving shaft D through the countershaft D. The
spindle A receives its reciprocating motion from an oscillating lever E, actuated
by a crank disc F on a shaft F1 through a connecting rod G. The crank dise Fis
driven by a spur wheel K on a shaft on which is keyed the driving belt pulley.J
as shewn at Fig. 3, said spur wheel K gearing with a spur wheel K' on a shaft H.
Elliptical wheels K are introduced on the shafts H', F, to accelerate the speed
of the crank at the dead centres, and thus give an approximately constant rate
of reciprocating motion to the buff spindle A. The spindle A is provided with a
top and bottom bearing, the top bearing being part of a slide L which, when the
machine is working, is rigidly fixed by means of a bolt M to another slide N
guided in the side cheeks of the machine framing, the slides being moved up and
down by the action of the oscillating lever E, which is attached to the back of
the slide N. When it is required to remove the work or to gauge the eye or hole
which is being lapped, the spindle A can be withdrawn by slackening the bolt M,
and raising the slide Ĺ together with the spindle A by a chain 0, attached at one
end to the slide L as shewn, the other end being fixed to a counterbalance weight;
or by means of a rack and pinion as most convenient. If a rack and pinion is
used for raising the slide L, the balance weight may be attached to a wire rope
passing over a pulley carried on the framework of the machine extended for that
purpose, the other end of the rope being connected to the top of the rack which
is bolted to the slide L. The slide N is balanced by a weight P. The work to be

page_text: operated upon when fixed to the table Q is moved with it through a circular path
the radius of which is equal to the eccentricity of the hollow pin or driver T to
the spindles A and U. The driver T is part of a slide which receives a greater
or less degree of eccentricity by turning a feed screw V, connecting it to the
spindle U, the screw serving to alter the said eccentricity from the maximum
until the centre of the driver T coincides with the axes of the spindles A and U,
in which position the slides R and S remain stationary although the driver T may
be revolving. The driving spinle Y is rotated by worm gearing W from a
shaft W, on the outer end of which is keyed a driving belt pulley X.
As the feed screw V revolves with the driver T when the machine is working, it
is then impossible to feed with sufficient accuracy directly by the screw, and
differential feed gear has been introduced to effect this. This gear consists of two
sets of three beveled wheels each, the outer wheels a, b, c, are all keyed to their
respective shafts, a being keyed to the hollow shaft. Y, to shaft d, and to shatt e
The inner set has only the wheel keyed to the lower end of the spindle U, the
other two bevelled wheels h, being loose on the shafts d and e. The wheel y
has one tooth more, and the wheel one tooth less than the wheel with which
they both gear. The feed serew V is connected to the upper end of the central
spindle by mitre wheels i, j, i being fixed to the screw V, and keyed to the
spindle U. When the machine is in motion, but not feeding, the inner spindle U
and unter spindle Y revolve together, the inner spindle U being carried round by
the wheel driving the wheel before it, the friction of the screw being suflicient
to prevent the wheel i from revolving on its own axis,
When it is desired to feed the driver T in or out, one or other of the clutches k, k,
keyed to the shafts d and e is brought into gear with one or other of the loose
wheels 9, Aby netunting the hand lever 1, when the inner spindle U is then slightly
retarded or accelerated as the case may be. The screw is thus made to rotate
on its own axis one way or the other giving the driver more or less eccentricity as
may be desired.
fy this means an eye of large or small diameter may be traversed or revolved
around the rotating grinding tool which is carried through the eye.
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 parts constituting the improved machine for grinding or
Japping round holes or eyes, substantially as hereinbefore described.
2. In a machine for grinding or lapping round holes or eyes the arrangement of
the grinding spindle A having a top and bottom bearing formed by slides permitting
of reciprocating movement of the spindle and of its withdrawal from the lower
bearing substantially as described.
3. To a machine for grinding or lapping round holes or eyes the combination of
an eccentric driver and a slide or slides arranged to traverse or revolve the work
around a rotating grinding tool substantially as described.
4. In a marine for grinding or lapping round holes or eyes the combination
with the driving spindles U, Y, of differential gearing arranged to operate the
feed screw V for imparting more or less eccentricity to the driver T acting on the
work carrier, substantially as described.
5. In a machine for grinding or fapping round holes or eyes the arrangement of
elliptical gearing and connections for imparting a constant rate of reciprocating
motion to the rotating grinding spindle substantially as described.
Dated this 11th day of October 1895.
WALLACE FAIRWEATHER,
Chartered Patent Agent,
62 Saint Vincent Street, Glasgow, Agent for the Applicant.