Improvements relating to Belt-shifting Mechanism and to the Appli- cation of the same to Machines for Grinding or Polishing Shafts and the like.
Year: 1889

page_text: COMPLETE SPECIFICATION.
Improvements relating to Belt-shifting Mechanism and to the Appli-
cation of the same to Machines for Grinding or Polishing Shafts
and the like.
I, ELWIN RUFUS HYDE, of 29 Osgood Street, Springfield, Massachusetts, United
States of America, Manufacturer, do hereby declare the nature of my invention and
in what manner the same is to be performed, to be particularly described and ascer-
tained in and by the following statement:-
My invention relates to a mechanical movement which is especially adapted for use
in connection with machines for grinding shafts and other cylindrical work, employing
one or more rotatable grinding wheels, but which is also applicable to a great variety
of machines in which a reciprocating carriage or table is employed.
The object of my invention is to provide for securing automatically the reversal of
the movement of the carriage or table in such machines, at each end of its movement,
the driving belts which actuate said carriage or table having a uniform speed, and to
secure such reversal of movement without any appreciable loss of time and without
causing any jar or waver to the machine.
To these ends my invention consists in the construction and combination of parts
hereinafter fully described and particularly pointed out in the claims.
In the accompanying drawings,
Figure 1 is a side elevation, partly in section, of a shaft grinding machine embodying
my invention.
Figure 2 is a similar view of the same or a similar machine, showing a slight
modification of a portion of the invention, as hereinafter referred to.
Figure 3 is an end elevation of the machine shown in Figure 2.
Figure 4 is an enlarged cross-section, taken at line x-x, Figure 2.
Figure 5 is a horizontal section of a portion of the machine, taken in the plane
indicated by line y-y of Figure 2.
Figure 6 is a detail view hereinafter referred to. The letter A designates the hed
or frame of the machine, which is supported on standards B, C the head-stock and D
the tail-stuck, each of which is provided with a mandrel for supporting and rotating
between them a shaft, and said head-stock being provided with the usual speed-
pulley E, whereby motion can be transmitted thereto from a counter-shaft.
A carriage G is mounted to travel in ways upon said bed, and upon said carriage
are mounted the transversely sliding blocks or carriages H, having mounted in
suitable hearings thereon shafts carrying the emery or other grinding wheels L,
pulleys K on said wheel-shafts enabling said wheels to be driven by belt from an over-
head shaft-drum P.
A feed-screw J mounted in bearings in said bed and extending longitudinally
thereof, engages a nut on said carriage G, whereby rotation of said scrow in either
direction will cause said carriage to move longitudinally of the bed in one or the other
direction, thus giving to the grinding wheels I. La lateral movement in addition to
their revolving motion. Such compound movement of the grinding wheels in addition
to the revolving movement about its own axis of the shaft being ground, ensures a
true and concentric grinding of the surface of said shaft.
It is obvious that the reversal of the movement of the feed-screw can be made to
limit the movements of the carriage in both directions, thus enabling the shaft to be
ground uniformly throughout its entire length, or otherwise as may be directed, and
it is to the means for driving said feed-screw, and to the means for reversing its
movement that attention now directed.
Said feed-screw at one end projects beyond the end of the frame or bed, as shown
at a, and has mounted thereon, two loose pulleys 10 and 12, and an intermediate fixed
pulley 11, said pulleys being of a uniform diameter.

page_text: An open belt 13 and a crossed belt 14 connect said pulleys with an overhead driving
or countershaft, as shown, said belts being adapted to be shifted laterally simul-
taneously, to first cause one and then the other to engage the fixed pulley and thereby
reverse the movement of the feed-screw. Also mounted upon said feed-screw, at its
extreme end, is a fly or balance-wheel 15, the function of which will be presently
explained.
Instead of mounting said pulleys and balance-wheel directly upon the feed-screw, as
shown in Figure 1, it will in some instances be found to be desirable to utilize the
construction shown in Figure 2, 3 and 5, in which a shaft. 8 suitably mounted in
bearings on the frame, and parallel with the feed-screw, carries said pulleys and
balance-wheel. A gear 7 on said shaft 8 by meshing with a gear on the feed-screw,
transmits the notion of the former to the latter. A bar 16 mounted to slide longi-
tudinally in bearings of the frame, carries the belt-shifting arms 17, 18, which are
provided with loops which embrace loosely belts 13 and 14. A bar 19 rigidly
connected with said belt-shifting bar 16 and sliding in similar bearings, ensures the
latter bar against rotation, or any of the usual means for securing such result may be
employed. A shipper-rod M, extending lengthwise of the frame and sliding in
bearing-lugs dd, carries the adjustable dogs ff, located upon opposite sides of the
carriage G, and projecting within the plane of movement of the latter.
A shaft 20, extending transversely across the frame, under the head-stock, and
beneath the plane of said belt-shifting bar and shipper-rod, receives a partial rotation
from and simultaneously with shipper-rod M, through a pin 22 projecting from a
collar 23 on said rod and on arm 21 on said shaft which receives within its slotted end
said pin. A second arm 24 on said shaft 20 receives within its slotted end a pin 26
projecting from a collar 27 on the belt-shifting bar 16, whereby the movement of the
shipper-rod is transmitted, through said shaft 20 to said bar.
Arm 24 of said shaft 20 is provided, between its ends, with a lug 28, which lug
terminates in two oppositely bevelled surfaces as shown, and which will hereinafter be
termed an "arrow head." Located in the same horizontal plane with said arrow head
is a second and oppositely located arrow head 30, which has its rear end reduced in
diameter and entered within barrel 32, supported upon a standard 31, said barrel
containing a stiff coil spring 33, which, by bearing against a shoulder on said arrow
head, keeps its pointed end in engagement with arrow head 28.
The operation of the machine is as follows:
Supposing the open belt 13 to be shifted upon fixed pulley 11, and said pulley to
drive the feed-screw, either directly or through the intermediate gearing as described,
in such manner as to cause the carriage to move from right to left upon the bed, such
right to left movement of the carriage will continue until the carriage is brought into
contact with one of the dogs f on the shipper-rod M, whereupon said shipper-rod is
moved to the left, and, through shaft 20, as previously described, transmits its move-
ment to shifting-bar 16, thereby shifting the open belt 13 from the fixed pulley 11 to
loose pulley 10, and the crossed belt 14 from loose pulley 12 to said fixed pulley. In
such shifting movement of said belts there is an appreciable instant of time when
both the open belt and the crossed helt occupy an equal extent of the surface of
fixed pulley 11, and exert an equal force upon said pulley in opposite directions, and
it is at this point that the balance wheel 15 performs its important function, since the
momentum acquired by said wheel compels the fixed pulley 11 to continue its move-
ment in the same direction until the open belt 13 is shifted entirely off from said
pulley. This result is still further facilitated by the action of the arrow heads 28
and 30, which are so arranged relatively to each other that, during the right to left
movement of the carriage just described, arrow head 28 will lie to the right of
arrow head 30, and that, when said belts reach said neutral point upon the fixed
pulley, the apex of arrow head 28 will have been carried just past the apex of arrow
head 30, whereupon spring 33 forces the latter into the position shown in the
drawings Figures 4 and 5, thereby forcing the shifting bar still further toward the
left and sufficiently to throw belt 13 entirely off from the fixed pulley, and belt 14
entirely on said pulley against the decreasing momentum of the balance wheel. An

page_text: instantaneous reversal of the movement of the feed-screw and of the carriage is
thus secured, which is repeated automatically at each end of the traverse of the
carriage.
:
In some classes of machines the fixed pulley 11, or the gears 6, 7, when the latter
are employed, may acquire sufficient momentum to secure the result just described
without the aid of an independent balance-wheel, but I prefer to employ said wheel
as it not only secures certainty of operation of the parts, but also increased steadi-
ness of movement.
In Figure 61 have illustrated an obvious modification of the construction previously
described, in which the two outer pulleys 11 are fixed pulleys and the intermediate
pulley 10 is a loose one, the operation being identical with that first described.
Having now particularly described and ascertained the nature of my said
invention, and in what manner the same is to be performed, I declare that what I
claim is:
1. The combination with a bed or frame, a carriage mounted upon said bed, and
a feed-screw for producing a reciprocating movement of said carriage, of fast and
loose pulleys and a momentum wheel or wheels operatively connected with said feed-
screw, and belt shifting mechanism for shifting a belt or belts from said fast to said
loose pulleys and vice-versa, substantially as described.
2. The combination with a bed, a reciprocating carriage mounted upon said bed, a
feed-screw operatively connected with said carriage and having mounted there on fast
and loose pulleys and a balance wheel, and reversely speeded belts engaging said
pulleys, of a belt shifter engaging said belts, a shipper-rod carrying adjustable dogs
to be engaged by said carriage at each end of its traverse, and intermediate connec-
tious substantially as described between said shipper-rod and said belt shifter, whereby
the latter will be actuated by the former, substantially as set forth.
3. The combination with a bed, a reciprocating carriage mounted thereon, a feed-
screw operatively connected with said carriage and carrying fast and loose pulleys, and
reversely speeded belts engaging said belts, of a belt shifter, a shipper-rod actuated by
said carriage at each end of its traverse, and a transversely disposed rock-shaft having at
one end an arm engaging said belt shifter and at its opposite end an arm engaging
said shipper rod, whereby the movements of the latter will be transmitted to the
former, substantially as described.
4. The combination with a feed-screw journalled in suitable bearings of a machine.
frame, a reciprocating carriage operated by said screw, and a shaft journalled in
bearings in said frame parallel with said feed-screw and having gear connection
with the latter, of fast and loose pulleys mounted upon said shaft, reversely speeded
belts engaging pulleys, a belt shifter engaging said belts, and intermediate connections
substantially as described between said carriage and said belt shifter whereby the
former will actuate the latter at each end of its traverse, substantially as set
forth.
5. The combination with a suitably journalled feed-screw carrying a gear of a
rotatable shaft carrying a gear which meshes with the gear on said screw and
having mounted thereon fast and loose pulleys and a balance wheel, reversely
speeded belts 13, 14, engaging said pulleys, a belt shifting bar engaging said belts,
horizontal rock shaft 20 having arm 24 engaging said bar, said arm carrying
arrow head 28, and an independent spring-actuated arrow head 30 adapted to
engage said first mentioned arrow head substantially as and for the purpose
described.
6. The combination with feed-screw J carrying gear 6, of shaft 8 carrying gear 7,
pulleys 10, 11, 12, and balance wheel 15, reversely speed belts 13, 14, engaging
said pulleys, belt shifting bar 24 engaging said belts, shaft 20 having arms 24, 21,
shipper-rod M, and carriage G, substantially as set forth.
7. In a shaft grinding machine, the combination with a bed or frame and the head
and tail-stocks for supporting and revolving a shaft to be ground, of a reciprocating
carriage G mounted upon said bed, transversely moveable block or carriage H,

page_text: mounted upon carriage G and carrying one or more grinding wheels, feed-screw J
engaging a nut on said carriage G and carrying gear 6, shaft 8 carrying gear 7
which meshes with gear 6 and having mounted thereon pulleys 10, 11, 12, and
balance wheel 15, open and crossed belts 13, 14, engaging said pulleys, belt shifting
bar 16 engaging said belts, shaft 20 having arms 24. 21. the former of which engages
said bar 16 and carries arrow head 28, spring-actuated arrow head 30, and shipper-
rod M carrying dogs ff in position to be engaged by said carriage J, and having a
pin engaging arm 21 of said shaft 20, substantially as described.
Dated this Soventh day of May 1940.
ELWIN RUFUS HYDE.
Haseltine, Lake & Co.,
45, Southampton Buildings, London, Agents for the Applicant.