A MACHINE FOR SURFACING THE INSIDES OF REVERSING LINKS
Year: 1882

page_text: LETTERS PATENT to Carl Pieper, Civil Engineer, and Patent Agent, resident
"
at 109-110 Gneisenaustrasse, Berlin, S.W. Prussia, for an Invention of
"A MACHINE FOR SURFACING THE INSIDES OF REVERSING LINKS
A com-
munication to him from Harry Friederichs resident in Hanover, Kingdom
of Prussia, German Empire
PROVISIONAL SPECIFICATION left by the said Carl Pieper at the Office of
the Commissioners of Patents on the 13th December 1882.
CARL PIEPER, Civil Engineer and Patent Agent, resident at 109/110 Gneisenau-
strasse, Berlin S.W., Prussia, "A MACHINE FOR SURFACING THE INSIDES OF
REVERSING LINKS," a communication from Harry Friederichs, resident in Hanover,
Kingdom of Prussia, German Empire,
The subject-matter of this invention consists in a novel machine for finishing
and readjusting the inside surfaces of reversing links of steam engines in hardened
state, the operation being carried out by a rotating grinding disc, combined with
suitable means for presenting thereto the surfaces of the link to be acted upon.
The said grinding disc is attached to a pulley actuated by a cord or strap and
rotating by means of its pivot in a bearing, which is so arranged that the disc,
the pulley and the bearing will freely enter into the slot of the link. The
disc is preferably made of emery, corundum or other hard material, but it may also
consist of metal in which are imbedded black diamonds or other stones having the
requisite hardness, or even pieces of very hard steel. The disc acts with its face,
but it is recessed in the middle, so that in fact only the outer annular portion of
the face will operate. The link is screwed to suitable slide-rests, which allow of
its being brought into the proper position in respect to the disc, and to be raised or
shifted as the work proceeds. These slide-rests are secured to a plate sliding on
ways, and to which a slow reciprocating motion is imparted in a direction parallel
to the link by any appropriate mechanical contrivance, such as are frequently used
in machine tools.
A small slide-rest carrying a holder with diamond, may be combined with the
machine for the purpose of cutting grooves into the grinding-disc when the same
is made of emery or other similar material.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Carl Pieper in the Great Seal Patent Office on the 6th June
1883.
CARL PIEPER Civil Engineer and Patent-Agent, resident at 109/110 Gneisenau-
Strasse, Berlin, S.W. Prussia; "A MACHINE FOR SURFACING THE INSIDES OF
REVERSING LINKS," a communication to me from Harry Friederichs, resident in
Hannover Kingdom of Prussia, German Empire.
The subject matter of this invention consists in a novel machine for finishing and
readjusting the inside surfaces of reversing links of steam engines.
As is well known, reversing links are ordinarily case-hardened in order to render
their working surfaces as resistant as possible. By this process, however, the
links are apt to become distorted, so as to require refinishing in hardened state,
which, with ordinary tools, is tedious as well as difficult. Moreover, such links
wear out unequally on their working faces, and have therefore to be made true
again from time to time. For this purpose they are, according to common practice,
first annealed, and then, subsequent to their adjustment, rehardened, whereby they
may again become distorted.
In the machine of my correspondent's invention, the finishing and readjusting of
the working surfaces of reversing links is carried out by a rotating grinding-disk
of particular form in combination with suitable means for presenting thereto the
surfaces of the link to be acted upon.
This machine is represented on the annexed sheet of drawings, Fig: 1. being a
front elevation, Fig: a side elevation, Fig: 3 a plan, and Fig: 4.a_sectional
elevation of the rotating grinding disk and parts connected therewith. Figs 5
and 6 show a modified arrangement of certain parts.
The grinding disk l is attached to a grooved pulley m rotating with its pivot n,
which is by preference double coned, in the bearing p mounted in the bracket q.
The height of the combined parts l m n and p is such that they will enter freely
into the slot of the link, as shown in Fig: 1. The grinding disk is preferably made
of emery, corundum or other hard material, but it may also consist of metal in
which are embedded black diamonds or other stones having the requisite hardness,
or even pieces of very hard steel. The disk acts with its face, but it is recessed in
the middle, at 1, so that in fact only the outer annular portion of the face will
operate, this arrangement having been adopted in order to give room for the
detached particles of metal on either side of the surface which is being worked, and
as the efficiency of the disk is thereby also in other respects increased.
The link is screwed to two brackets e e by preference provided with the studs or
pins oo for carrying the link. The said brackets are attached to the slides ff of
the vertical slide-rests g g, which in their turn are secured to the slides & d of two
horizontal slide-rests r. It may thus be brought into the proper position in
respect to the disk, and be raised or shifted as the work proceeds. The slide-
rests are attached to the plate c, sliding lengthwise on horizontal ways forming
part of the machine frame. The hand-wheels h of the vertical slide-rest spindles
are connected together by the rod h¹, in order to insure an equal rotation of both
spindles, when the link is to be raised or lowered bodily, but this rod may be
detached so as to allow either spindle to be turned independently of the other one,
when required. In a similar manner the hand-wheels ii of the spindles of the
horizontal slide-rests are connected by the rod . The plate c is provided with a
rack in which gears the pinion b Fig. 2, fixed on a transverse shaft, at the other
end of which there is a worm wheel t actuated by a worm on the shaft u. This

page_text: shaft, besides, carries the fixed pulley a and the loose pulleys a' a', by means
whereof and of a crossed and an open strap, running over the said pulleys and the
pulley of a driving shaft, together with the requisite strap-shifting device, the
shaft u may be alternately rotated one way and the other in the well known
manner, a longitudinal reciprocating motion being thus imparted to the plate c
together with the slide rests and the link. The grinding-disk is at the same
time rotated by a cord running from a pulley on the driving shaft over the guide
rollers n' n' to the pulley m.-After one face of the link has been finished, it is
necessary, for grinding the second face, to reverse either the link or the grinding
disk. If a reversal of the link is to take place, as has been supposed in the
arrangement Figs 1, 2 and 3, it is advantageous to fit the screws of the
brackets e e in such a manner that, after having detached the brackets from
the slide-rests, turned them round together with the link and fastened them again
to the opposite slide-rests, the link will present its other working face exactly in
the proper position to the grinding disk. In case, however, the disk is to be the
reversible part, the same may be mounted as shown by Figs 5 and 6 in a bracket q¹
rotative on a stud forming part of the slide u and adapted to be secured to the
latter by screw bolts u¹, the heads whereof engage in a circular groove concentric
with the said stud, a construction often applied in machine tools. The slide u is
adjustable on the standard v by the screw v¹. Before reversing the disk it is
necessary to entirely withdraw the driving cord from the holes in the apparatus
through which it passes and subsequently to replace the same.
When the grinding disk ? consists of emery or corundum it is of advantage to
cut small circular grooves into the acting surface by means of a diamond. This
may be done on any suitable lathe; but, to insure the complete accuracy of
workmanship, a small slide-rest s carrying a holder with diamond has been
arranged in the plate c, so that the grooves in the operating surface of the disk
may be renewed while it rotates in its own bearing.
Having thus described the nature and object of this invention and the manner
in which it is to be carried out in practice, as communicated to me by my
correspondent, I hereby claim as new and important features of the same:
1, The rotating grinding disk having the recess and acting with the outer
annular portion of its face on the inside working face of a hardened reversing
link, in combination with means for imparting to the link a longitudinal
reciprocating motion, substantially as and for the purpose specified.
2, In combination with the grinding disk arranged as described, the slide-rest 8
with diamond holder, as and for the purpose described.
In Witness whereof I the said Carl Pieper have hereunto set my hand and
seal this twenty third day of May in the year of our Lord 1883.
CARL PIEPER (L.S.)