Improvements in Grinding Machines.
Year: 1891

page_text: COMPLETE SPECIFICATION.
Improvements in Grinding Machines.
I, JAMES YATE JOHNSON of 47 Lincolns Inn Fields, in the County of
Middlesex, Gentleman do hereby declare the nature of this invention which
has been communicated to me from abroad by Allen Johnston of Ottumwa
in the County of Wapello, State of Iowa Manufacturer, and in what manner
the same is to be performed to be particularly described and ascertained in
and by the following statement:-
.
The present invention has reference to the construction of machines for grinding
various articles such as dics, lathe spindles, mandrels, arbors and the like.
For this purpose use is made of a hollow or cup shaped grinder, adapted to
receive a certain quantity of water, and to spread it by centrifugal action over the
grinding edge of the wheel. The use of a hollow or cup shaped grinder is not new
broadly. According to the present invention, however, the grinding wheel is
mounted upon a vertical arbor, and the grinding edge rotates in a horizontal plane.
This arrangement has great advantage in maintaining the supply of water and
distributing it equally over the grinding surface in such quantity as to conduct
away the heat generated by friction.
The arbor of the grinding wheel is made adjustable and provided with a gauge to
regulate and determine the adjustment with nicety.
The slide
The invention also includes improvements in the automatic feed, which consists
of a slide, and work-holders, (such as a chuck) carried thereby.
reciprocates horizontally above the trough containing the grinder, and is provided
with reversing mechanism for changing its direction, and with means for fixing the
limits of its travel at any desired length. It also includes the particular
construction of the work-holders, as hereinafter set forth.
The said slide is provided with driving mechanism for actuating the same either
by hand or by power, and with means for connecting the slide with, and dis-
connecting it from, a driven shaft of the machine.
The bed upon which the slide reciprocates is adjustably connected with the main
frame and adapted to be tilted upon a centre, so as to present the work at different
angles to the edge of the grinding wheel, to produce flat, convex, or concave
surfaces as desired.
The invention also includes certain details of construction, and certain arrange-
ments and combinations of parts, as hereinafter set forth.
In the accompanying drawings which form part of this Specification,
Fig. I is a sectional elevation, looking from the rear of a machine constructed in
accordance with the invention, the section being taken on line B, B (Fig. III);
Fig. II is a plan view partly in horizontal section on line A, A (Fig. III);
Figs. III and IV are vertical cross sections on lines C, C and D, D,
(Figs. I and II) respectively;
Fig. V is a longitudinal section partly in front elevation;
Figs. VI and VII are details of parts of the reversing mechanism; and
Figs. VIII and IX are details of the work-holder for mandrels and other cylin-
drical articles.
1 represents the main shaft of the machines. It is supported in bearings in the
lower part of the main frame H and communicates motion through bevel gears 41
The latter
and 42 to the lower arbor J, which carries the grinding wheel K.
rotates in a trough H' which constitutes the upper part of the machine frame, its
upper edge extending some little distance above the top of wheel K, and being
slightly turned in to catch and direct downward the water thrown from the edge of
the wheel.

page_text: Gear 42 is connected to arbor J by a spline and groove (Fig. III) so that said
arbor can be adjusted longitudinally with reference thereto. The arbor is encased
for the greater part of its length in a sleeve L whose upper end constitutes a
bearing for the supporting plate k of the grinding wheel. A portion of the outer
periphery of sleeve L is threaded and is engaged by a spur gear whose hub is
threaded interiorly. Sleeve L is provided at 15 with a feather, which takes into a
groove in the frame preventing the rotation of the sleeve. Wheel is engaged by
a pinion 16 carried by a stud 17, provided at its upper end with a crank-handle 18
and with an index or pointer 19. By turning handle 18, sleeve L and with its
arbor J and wheel K, can be adjusted to a nicety. The. index finger 19 indicates
on a graduated scale the extent of the adjustment in thousandths of an inch. The
supporting plate k of the grinder carries at its edge a ring M fastened thereto by
screws m and to this ring the cylindrical grinding wheel is fastened by screws m³.
The arrangement of the moveable ring M is adapted to facilitate removal of the
wheel by removing screws m the screws m¹ being inaccessible.
The tubular part of the grinding wheel is composed of an upper part K of
abrading material, such as emery and a suitable binding agent, and a supporting
part or base K¹ to which the grinder proper is moulded.
N (Figs. I and II) indicates a spout for conveying water from trough H¹ to the
interior of wheel K. The water may be applied by any convenient means, such as
the cylindrical pump N', carried by shaft n, and driven by belt n from pulley 20
on the main shaft.
I will now describe the work-holding and feeding devices and their actuating
mechanism. F represents a long slide extending horizontally lengthwise of the
machine above the trough H¹. On its front side (Fig. I) it carries the work
holding devices, as presently described, and at the rear (Figs. I. II. III) it rests
upon a bed or support G, upon which it can reciprocate longitudinally. The
adjustable attachment of this bed to the main frame is shown in Fig. 1. The
vertical flange G₁ of the bed is provided with curved slots g all struck from
the centre of shaft 21, through which power is transmitted to the slide.
The bed is attached to the frame by screws g'. The bed, can by this arrange-
ment be tilted to bring the work perfectly square with the edge of the grinding
wheel, or to present it thereto at an angle as may be desired.
To adjust the bed, a threaded bolt 22 (Fig. 1) is provided. It engages a threaded
boss 23 on the bed, and the latter is provided with a pointer 24 opposite a graduated
scale to indicate the position of the bed.
The slide has on its under side a rack f (Figs. III and IV) with which
engages a toothed wheel 12 mounted on shaft 13 which rotates in bearings of bed G.
For the purpose of moving the slide by hand a pinion 26 engages wheel 12, said
pinion being carried by a spindle 27 having on its front end a crank handle 28.
Said spindle is enclosed by a long sleeve 29, in which it can ordinarily turn loosely.
Sleeve 29 is split at the end and terminates in a taper at 30. The tapering end is
surrounded by a ring 31, and when the latter is forced to the left (Fig. IV) by
means of the nut 32, sleeve 29 will be clutched to spindle 27, and the two will turn
together. This is the position of the two parts when the slide is run by power.
The motion is derived from shaft 21, provided with pulleys 33, adapted to be driven
by a band from pulleys 34 on main shaft I (Fig. III). Shaft 21 drives two
wheels 3 and 5 (Fig. II) the former directly from pinion 4, and the latter through
an idler 2 from pinion 1. Consequently wheels 3 and 5 rotate at the same speed,
but in opposite directions, and as these wheels alternately communicate motion to
the slide as presently explained, the direction of the slide's movement will depend
on whether it is driven for the time being from wheel 3 cr wheel 5. These wheels
are mounted loosely on their spindle 44 (Fig. VI) and the latter has a pinion 10,
which engages and turns gear 8 in one direction or the other, and the latter which
is keyed to the sleeve 29, transmits its motion through said sleeve spindle 27,
pinion 26, and gear 12 to the rack as already described.

page_text: It requires now to be shewn how the direction of rotation of spindle 44 is reversed
when the slide F reaches the predetermined limit of the movement in either direction.
Around 44 and between the wheels 3 and 5 is a ring 45 (Figs. 11 and VI). To
this ring is connected by means of a pin 46, a rod 47. Pin 46 passes through a slot
in spindle 44, so that the rod 47 is free to reciprocate lengthwise of the spindle,
carrying with it the ring 45. The latter has on each face a pin p (Fig. II) and
the wheels 3 and 5 have on their adjacent faces, similar pins 7. Consequently,
when the pins of ring 45 engage the pin of wheel 3, spindle 44 will turn with the
latter and will move the slide, through the gearing described, in one direction.
When in like manner the ring is connected with wheel 5, the slide will move in the
opposite direction.
Rod 47 is reciprocated by means of an arm 48 of rock shaft 49, journaled at 51
on the bed G. (Fig. II). This shaft has an arm 50 (Figs. I and 111) which
projects over slide F, and the latter is provided with stops 52, in the path of this
arm, which on striking one of them will cause rock-shaft 49 to turn, disengage
ring 45 from the wheel (3 or 5) which at the time is moving the slide, and cause it
to engage the other wheel, thus reversing the movement of the slide. In order to
throw the pins p on the ring quickly and certainly into engagement with the
corresponding pins 9, I employ a conical pointed spring-actuated pin 55, shewn in
Fig. VII in detail. As shewn in Fig. Il the end of this pin is in contact with the
wedge-shaped end of arın 48 of rock shaft 49. As the arm 48 moves, in either
direction, it forces pin 55 back against the pressure of its spring, until it passes the
point of said pin when the latter springs out and throws the ring 45 into engage-
ment with the wheel 3 or 5, as the case may be.
It will be understood that this reversing mechanism is not broadly new, and is
not claimed as an essential part of the apparatus. Any suitable reversing mechanism
could be employed without departing from the spirit of the invention.
The two stops 52 are set in an undercut groove 53 (Fig. IV) in the slide, and
are adjustable lengthwise thereof, so as to fix to the desired points the limit of
motion of the slide, which for some work (mandrels for example) would be much
longer than for other kinds, such as dies.
By reference to Fig. IV it will be observed that the spindle 27 and the sleeve
surrounding it pass through a tube o, which crosses the trough H', and is sufficiently
large to permit to the shaft and its sleeve all the play necessary in adjusting the
bed G. This tube O also serves to stiffen the frame. The trough is entirely tight
and all the gearing and working parts are protected from access of water.
The work holding devices will now be described. For grinding dies and short
pieces of work, a chuck is detachably secured to slide F near the middle thereof,
(Figs. III and V). The detachable connection is made by means of plate 60
secured to slide F by a threaded bolt 61, provided at its upper end with a handle 62,
so that the chuck can be adjusted towards and away from the wheel K. Plate 60
has at its lower end a curved undercut flange 63 which receives the base 64 of the
chuck. The latter has a circular hub of dovetail shape in cross section, as shewn
in Fig. 111, which fits under the flange 63 and is held in place by a holding
plate 65. Plate 65 can slide in a recess in plate 60 and is retained by the head of
screw 66. Through the centre of base 64 passes a bolt 67, upon the end of which
is screwed a nut 68. The latter secures to the circular base 64 those parts of the
chuck which are ordinarily detached in changing from one chuck to another or in
grinding work which is rotated against the grinding wheel. The circular base 64
is not ordinarily removed. Its function is to permit the chuck to be readily turned
on its axis in a plane transverse to the grinding surface. This function is useful
for several purposes. In this particular machine, inasmuch as the work is introduced
underneath the chuck, there would be difficulty in placing it accurately. By this
arrangement the chuck can be inverted, the work properly placed in position, and
the chuck then turned back to bring the work to the wheel. Moreover, this axial
adjustment of the chuck permits dies and other articles having two inclined faces

page_text: to be ground by inclining the chuck one way and grinding say on the inner
edge of the wheel, and then tilting it the other way and grinding against the outer
edge.
The plate 70, which rests against the circular base carries the moveable jaw 69
and the two stationary jaws 71 and 72 (Fig. V). The moveable jaw which is
between the two stationary jaws slides upon a dovetailed projection or rib 170, on
plate 70.
In
Jaw 69 has on its upper edge a projection 75, placed a little to one side of the
centre shaft, and on its lower edge a similar projection 76. These projections form,
with the stationary jaws 71, 72, four work-holding spaces of different sizes.
Fig. Va die W is shewn as being held in the longest of the spaces. The sizes of
these spaces can be regulated by screw 80, (Fig. V) by means of which the
moveable plate or jaw 69 can be moved in either direction.
When cylindrical work is to be ground, the chuck is removed by unscrewing
nut 68 and taking off the plate 70 and the jaws, and the mandrel, spindle or other
object is held between centres, as in a turning lathe, Fig. V shows the puppets P Q
Pbeing the head-stock (shown separately in Figure VIII) and Q the tail-stock
(shown in Figure IX). Each of these devices is secured to the slide by a T-headed
stud T, which is held in a groove in the slide, (Figure IV) and secured by a nut r¹.
These holders are provided with the usual centering pins.
The head-stock P has several adjustments. It can be moved lengthwise of the
slide and it can be adjusted axially to any desired position as for grinding objects
to a cone or taper. It can be removed from the position in which it is shown and
placed on the circular base of the chuck, for grinding wheels, discs or other objects
that have to be rotated against the work. It can then be turned a quarter turn
from the position shown in the drawings, and so present the face of a wheel,
properly chucked to the face-plate 82 of the live spindle, to the edge of the
grinding wheel. It may also be turned to an oblique position to grind either
convex or concave surfaces as desired.
The frame of the head-stock is formed of two castings 85, 86 which meet at the
line 5 (Figure VIII) so that by separating them access is given to the gearing,
driving spindles etc. enclosed therein. In Figure V (the front casting or half of
the frame being removed) the spindles and mitre pinions are shown, their bearings
being formed by recesses of proper shape in these castings.
The centre of the head-stock is carried by the live spindle w, which is enlarged
near the outer end. It can be adjusted to take up wear by means of nuts 87, 88.
To this spindle, is keyed a mitre pinion which engages a similar pinion y on an
upright spindle (Figure V). The latter is driven from a horizontal spindle, 89
through pinion 90. 91. (Figure IV). Spindle 89 has on its outer end a small band
pulley 100, adapted to be driven from a counter-shaft. It will be observed that
the adjustment of the holder, whether axially, to incline the object being ground, or
lengthwise of the slide, is always in the plane of the pulley 100, so that the latter
will not be thrown out of line with the driving pulley of the countershaft.
It will, of course, be understood that an ordinary compensating pulley on the
counter shaft must be used to provide for the lengthening and shortening of the
driving belt as the pulley 100 reciprocates with the slide.
The dead spindle 101 of the tail stock is pressed out by a helical spring 102, and
an adjusting nut 104 is provided to regulate the compression of said spring against
the shouldered end of sleeve 103 which surrounds said spindle.
The head and tail stocks can be adjusted on slide F towards and away from each
other to hold work of different lengths, the studs being loosened and slid along in
groove s as already described.
The foregoing description and the drawings referred to therein, set forth and
illustrate what is believed to be the best embodiment of the principle of the inven-
tion; but it will be understood by persons skilled in the art that modifications may
be made in details of construction and arrangements of parts, and that some one or

page_text: more of the improvements described may be used separately and apart from the
others without departing from the spirit 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. For use in grinding dies, mandrels, and like articles, a hollow or cup-shaped
composition wheel mounted on an upright shaft and having means for supplying
water to the interior of the wheel, whereby the combined action of centrifugal
force and gravity maintains a regulated stream of water over the edge of the
wheel where the grinding is performed substantially as and in the manner
hereinbefore set forth.
2. In grinding machines of the character described, a cup-shaped wheel arranged
to rotate in a horizontal plane, adapted to contain water and to spread the same
over the grinding edge, combined with reciprocatory work-holding devices, as
hereinbefore set forth.
3. The combination of the hollow grinding wheel, a ring detachably secured to
one end thereof, and a base plate detachably secured to the ring substantially as
hereinbefore described and shewn in the accompanying drawings.
4. The combination with the grinding wheel, its arbor, and gearing for rotating
the latter, of a sleeve loosely surrounding the said arbor and held from rotation
therewith said sleeve and arbor being connected so that the latter follows the
longitudinal movements of the former, and means as specified for adjusting the said
sleeve longitudinally and an adjustment indicator substantially as hereinbefore
described.
5. In machines of the character described the use of a grinding wheel comprising
a base-plate, a ring detachably secured to the said plate, and a cylindrical part
composed of a metallic tube secured to the said ring and an upper portion of
abrading material moulded to the said metallic part substantially as herein before
described.
6. The combination with the frame and grinding wheel, of a bed adjustable on
a centre with reference to the said frame, and a slide supported and moveable in
the ways of the said hed and carrying work-holding devices, substantially as
hereinbefore described.
7. The combination with the hollow grinding wheel, on a vertical arbor, of a
slide, carrying work-holding devices, and a bed having ways in which the said slide
can reciprocate the said bed being adjustable on a centre so as to incline the
slide more or less from a horizontal plane substantially as hereinbefore described.
8. The combination with the grinding wheel of a work-holding slide, a bed
carrying the said slide, a shaft and gearing for transmitting motion to the said
slide the said shaft being journalled in bearings on the said bed, and the latter
being adjustable on an axis concentric with the said shaft, substantially as
herein before described.
9. In grinding machines of the character described, the combination with the
grinding wheel adapted to contain water, of the bed and slide, and gearing enclosed
by the said bed, whereby motion is communicated from a suitable shaft to the said
slide, substantially as hereinbefore described.
10. In grinding machines having a hollow grinding wheel, the particular con-
struction of the work-holding chuck having an axial adjustment in a plane
transverse to the plane of the grinding surface of the wheel, as hereinbefore set
forth, so that the work may be presented either to the inner or to the outer edge
of the wheel without removal of the work from the chuck as hereinbefore set
forth.
11. In grinding machines having a hollow grinding wheel, the work-holding
chuck secured to a slide and adjustable axially, and also adjustable towards and
away from the said wheel, substantially as herein before described.

page_text: 12. In grinding machines of the character described, the work-holding chuck
having jaws, one of which is adjustable, forming work-holding spaces of different
sizes on opposite edges, the said chuck being reversible, as hereinbefore set forth.
13. In grinding machines of the character described, the combination with the
slide, of the head-stock and tail-stock, constructed and adjustably secured to the
said slide substantially in the manner shewn in the accompanying drawings and
hereinbefore described.
14. In grinding machines of the character described, a hollow wheel, adapted to
contain water and spread it by centrifugal force over the edge of the wheel, com-
bined with a reciprocatory slide carrying a head-stock and tail-stock provided with
centres, and with means for rotating the work on the said centres substantially as
shewn in the accompanying drawings and hereinbefore described.
Dated this 22nd day of December 1891.
J. H. JOHNSON & Co.,
47, Lincoln's Inn Fields, London, W.C., Agents.