IMPROVEMENTS IN MACHINES FOR GRINDING AND DRESSING FILE BLANKS
Year: 1883

page_text: LETTERS PATENT to Alfred George Brookes of N° 59 Chancery Lane in the
County of Middlesex Patent Agent for an Invention of IMPROVEMENTS IN
MACHINES FOR GRINDING AND DRESSING FILE BLANKS communicated to him
from abroad by Alfred Weed of the City and County of Philadelphia in the
State of Pennsylvania one of the United States of America
COMPLETE SPECIFICATION filed by the said Alfred George Brookes at the
Office of the Commissioners of Patents on the 7th November 1883.
.
ALFRED GEORGE BROOKES of N° 59 Chancery Lane in the County of Middlesex
Patent Agent IMPROVEMENTS IN MACHINES FOR GRINDING AND DRESSING FILE
BLANKS communicated to me from abroad by Alfred Weed, of the City and
County of Philadelphia in the State of Pennsylvania, one of the United States
of America
The following is a specification of my improvements reference being had to the
accompanying drawings wherein Fig: 1 is a front view of the machine in
perspective showing the general distribution of parts. Figs 2 and 3 are respectively
front and rear elevations thereof. Fig. 4 is a longitudinal vertical section on the
line x, x of Fig: 2, and Fig: 5 is a vertical longitudinal section, on an enlarged
scale through the centre of the grindstone shaft, shewing certain details of the
adjusting mechanism.
My invention consists in a machine whereby a number of file blanks may be
ground or dressed at once, the movements being as far as possible automatic, and
the working parts being so constructed and combined as to permit the placing of
the blanks in position, their examination during the grinding, and their removal
when finished without interrupting the movements of the machine. Furthermore
since to ensure uniformity and accuracy in the blanks it is essential that the
movements of the working parts should be true: my invention further consists in
means whereby, all these parts can be readily and minutely adjusted. I also
provide a device for dressing and truing the face of the grindstone.
To facilitate comprehension of the more detailed description hereinafter given,

page_text: the main features of the machine may be pointed out by reference to the perspective
view shewn in Fig 1.
A frame F¹, in which the blanks (indicated by dotted lines) are held, is vertically
reciprocated in a direction tangential to the periphery of the revolving grindstone C
This reciprocation is effected by screw and bevel gearing above the frame actuated
alternately in opposite directions by belts automatically shifted upon the pulley G
The grindstone is also reciprocated continuously in the direction of its axis of
rotation, and across the face of the frame F¹.
The bearings of the grindstone shaft are adjustable towards and from the
frame F¹, and the latter is held against the grinding face by rollers P, which are
also separately adjustable, all these adjustments being effected by means of a single
hand wheel M The device C, for dressing the grindstone face is vertically
adjustable towards the surface of the stone and can also be drawn laterally
across it.
The following is a description of the various details. The frame A, of the
machine rests upon baso girders B, which are secured together by end plates B¹,
A bridge B2, braces the upper ends of the frame A, and supports the mechanism by
which the file blank frame is reciprocated. D¹, D¹, are pillow blocks forming
bearings for the grindstone shaft D which is driven by the pulleys C, C, The
grindstone C', is secured in position between the disks C³, one of which is rigidly
attached to the shaft D and the other is adapted to move therein being clamped
against the stone by means of nut N, working upon a threaded portion of the shaft.
One end of the shaft D, has a cam slot D2, formed in it and a pin D³, in the eyo
piece D', secured to the pillow block D', fits in the cam slot D2 and causes the
shaft D, carrying the grindstone to reciprocate laterally during its rovolution. The
pillow blocks D, D', slide upon the girders B, B, their movements being controlled
by the screw rods O, which together with their adjacent mechanism are shown on
an enlarged scale in fig: 5 The screws O, engage with sleeve nuts O¹, revolving
in suitable bearings in the frame A, and secured against longitudinal movement by
collars O³, and M³. The collars M₁, are provided with mitre gears as shewn which
engage with corresponding mitre-gears M, upon the shaft m, mounted in projecting
bearing pieces L, and actuated by means of the hand wheel M, and as tho
screw O, and its nut O¹, on one side of the machine are threaded in the reverse
direction from that of the similar screw and nut on the opposite side, it is obvious
that the rotation of the hand wheel M, in either direction will shift both the pillow
blocks D¹, D¹ together towards or froin the frame A. A cross head F³, is adapted
to move vertically in guides F, within the frame A. The cross head is cast with a
central enlargement or socket to receive the end of the actuating screw' held
securely in position by means of the pin F, which passes through both the cross
head and screw. Beneath this socket and at right angles to the cross head F³, is
the transverse extension b, longitudinally slotted as shewn at a in Fig 4 to receive
the carriage F16, the cross-section of the slot end of the carriage F10, being indicated
by the dotted lines in Fig: 3. A screw F15, extends from end to end of the slot,
passing through a correspondingly threaded opening in the carriage F. It will
thus be seen that while the carriage F, may be adjusted at any point in the length
of the slot by turning the screw F1, its weight does not rest upon said screw,
is sustained by the inclined sides of the slot a. The carriage Fie, is provided with
two pendent lugs upon its under face bored out for the reception of a bolt F¹³,
which passes through the eye of the suspension rod F³, The open rectangular
frame F¹, is secured to tho lower end of the rod F³, by means of the screw thread &
and the jam nut F. Within the rim or flanges formed by the sides of the frame F¹,
is snugly fitted the plate F, secured in position by means of the bolt and
latch ff, which hold it against the diagonal projections across the corners of the
frame. The plate F is provided, on the side adjacent to the grindstone with
parallel cross pieces f', forming rests for the file blanks f, the tangs of the latter 5
being inserted behind a cross piece f³, at the bottom of the plate F. Rollers P P
journalled upon carriages Q, Q, are arranged to bear against the back of the
but

page_text: frame F (or that side which is furthest from the grindstone) but clear of the
plato F, so as not to interfere with its removal at any time from the frame F.
The carriages Q Q slide in horizontal dove-tailed guides K. K. on the main frame A.
Each carriage being formed with an inside thread engaging with a screw P¹. and
the screws P. Pl. whose threads run in opposite directions being actuated by means
of the mitre-gears M³. Mr. and Ms. Mo. respectively. The mitre-gears M*. and M³ are
mounted upon the shaft m already referred to and by the rotation of the hand-
wheel M, can be adjusted towards or from the frame F. thus causing the blanks
supported on the plate F to bear more or less closely against the face of the
grindstone C'. Each of the mitre-gears M. M². M. M. M. M. M' and M³ is secured
to its shaft by a set screw as indicated by loosening which the gear is released, and
the shaft remains stationary, whilst the others are revolved. This enables the
operator to readily correct any want of parallelism in the adjustable carriages QQ.
or pillow blocks D¹. D' by loosening the gear. which may be too far back and
rotating the other until the proper point is reached for causing it to again engago
with its shaft so also the pillow blocks may both be moved simultaneously without
affecting the position of the rollers and vice versa.
The devices for causing the vertical reciprocation of the frame F¹. are as
follows:-A screw F is secured to the moveable cross head F³. and engages with a
nut bevil gear F°. revolving horizontally in bearings upon the bridge B². A
corresponding bevil pinion F. meshing with the gear F. is secured to the
horizontal driving shaft H. mounted in bearings I. I. and provided with two loose
pulleys G. G. and an intermediate fast pulley G. Standards J. J. upon the
bridge B, support the sliding bars E. and E7 the former of which carries the belt
shifters E. E. and the latter the similar belt shifters Es E. The bars E and E7.
are moveable independently of one another but that end of the bar E7 which
carries the belt shifters F. abuts against the projecting side of the belt shifter E³.
so that when the bars are in the position shown in Figure 3. the movement of the
bar E to the left or towards the central pulley G will push the belt shifters Eº.
and bar E. towards the loose pulley G¹. Conversely when the belt shifters Eº. are
upon the loose pulley G. and the belt shifters Es are upon the central pulley G the
movement of the bar E. and its belt shifters E to the right or towards the
central pulley G will push the bar E. and bolt shifters E³ towards the loose
pulley G.
It will be observed, however, that this combined or joint movement of the bars
only takes place when the belt shifters are upon immediately adjacent pulley and
then is only effected through the movement of the bar whose belt shifters are for
the time being upon a loose pulley: thus supposing the bars to be in the positions
shown in Figure 3 if the bar Ed (whose belt shifters E, are then upon the fast
pulley G) should be moved to the left or towards the loose pulley G¹, the bar E7
will remain stationary, the belt shifters will be in the position shown in Figure 2,
and then neither bar will by its movement affect the other. Connecting rods
E' E are respectively secured to the bars E7 and E by clamps E2 and E³. The
connecting rod E* is actuated through the bell crank E and the rod E³ through a
similar bell crank E. The shafts or pivots of these bell cranks extend across the
under side of the bridge B³ (as shown in Figure 4) so that the upright arms of the
bell cranks are upon the same side thereof as are the sliding bars, whilst the
horizontal arms are on the opposite side. Pieces F10 F10 are mounted upon a
horizontal arm projecting from the top of the screw F1 the other upon the sliding
cross-head F3 carrying the bar F. upon which the tap pins F. and Fiz are supported
in vertically adjustable clamps. The picces F10 F1 are tapped with a number of
screw holes so as to permit the lateral shifting of the bar F.
The construction of the grindstone dressing devices is as follows: A horizontal
shaft A³ having at one end a cross, handlo A is freely suspended in bearings A² A²
which, slide vertically in ways A'A' cast upon the side of the frame A adjacent to
the grindstone C. The sliding bearing pieces A³ A² are centrally threaded to

page_text: engage with the vertical screw A A³ provided with nitre-gears A which are
actuated by means of the pinion shaft AB and hand wheel A7. As the screws
A' A are threaded in. opposite directions the rotation of the hand wheel A7 moves
the bearing pieces A² simultaneously in the same direction; the operator is thus
enabled to impart a slow upward or downward motion to the shaft A³ moving it
towards or from the grindstone. The gears A being secured to their respective
shafts by set screws (similar to those already described in reference to the
gears M M et cetera) parallelisin of the shaft As with the grindstone face can bo
ensured. Secured between collars clamped upon the shaft A³ are several toothed
dressing discs C¹
The mode of operation of the machine is as follows:-
Should the grindstone require to have its surface trued, power is applied to its
driving pulley C and when the stone is in rapid rotation the hand wheel A' is
turned so as to adjust the dresser shaft A³ towards it. When the toothed discs C
have been brought into contact with the face of the stone they are drawn back and
forth across it by means of the handle A' until the stem is cut or dressed true,
when the shaft A³ is raised clear of the stone by reverse rotation of the hand-
wheel A. A number of the roughly formed file blanks are then secured 'in the
plate F, and the latter is placed within the frame F' and locked therein by means
of the latch device f³. f. Figures 2. 3. and 4 show the plate and blanks in place
the frame F banging in a vertical position on the pivot bolt F18 and the screw F³
being at the extreme upward point of its movement. The grindstone having been
set by means of its sliding bearings D' D¹ in the proper position for acting upon
the blanks during the vertical reciprocation of the frame E¹ and the rollers P. P.
having been adjusted so as to bear against the back of the frame; power is applied
to the belts upon the pulleys G. G. and G. As is indicated by the arrows
(Figure 2) the belts upon the loose pulleys G¹ and O' are running in opposite
directions, and it being desired to cause the descent of the screw F" the belt
shifters E. ES are moved by hand so as to shift the belt from the loose pulley G'
on to the fast pulley G the other belt shifters E E° remaining stationary. The
rotation of the pulley G and shaft H. in the direction of the arrow upon G³ causes
the nut bevil gear Fe to turn to the left (or in a direction opposite to the hands of
a watch) and thus forces the screw F³ and cross head F downward. When the
screw F approaches the extremity of its downward movement the tap-pin F
strikes the horizontal arm of the bell crank E' depressing it, and through tho
connecting rod E³, and bar Eº, moving the bolt shifters E. E. on to the central or
fast pulley G. As has been before explained this movement pushes the belt shifters
Es. E. on to the loose pulley G2 thus reversing the motion of the fast pulley G
causing the ascent of the screw F8 and cross head F³. When the screw F³
approaches the end of its upward movement (as indicated in Figure 3) the tap
pin F1 strikes the horizontal arm of the bell crank E raising it and throwing the
belt-shifters E8. E. on the fast pulley G This movement pushes the belt shifters
E. E. on to the loose pulley G¹ and the motion of the fast pulley is again reversed
so as to cause the descent of the screw. By adjusting the tap pins at different
points upon the rod F, the stroke of the screw F³. can be varied in length to any
desired extent. The frame E¹. is by these movements of the scrow F and cross
head F³ caused to reciprocate vertically in a plane tangential to the periphery of
the grindstone C¹, and the pressure of the rollers P. P. against the back of the
frame forces the file blanks into close contact with tho rapidly revolving stone.
As has before been explained the stone itself has a lateral reciprocating motion
caused by the pin D³ and cam slot D2 and the grinding is effected by their
combined movements of vertical and horizontal reciprocation This method not
only prevents the formation of lines and ridges in the file blanks from inequalities
in the grinding surface, but obviates the uneven wearing away of the stone itself.
The arrangement of mechanism shown in Figures 6, 7. and 8. may be substituted
for the cam slot D³and pin D³ above described for effecting the reciprocation of

page_text: the grindstone in the direction of its axis. Figure 6 is a side elevation of the
stone and adjacent mechanism. Figure 7 an end view, and Figure 8 a plan view
thereof
Instead of forming a cam slot upon the grindstone shaft D, I secure thereto two
collars d' d' a short distance apart. A vertical lever arm d³ extends into the space
between the collars d' d' and is rigidly attached at its lower end to a rock
shaft a' mounted in bearings as a which project laterally from the frame A.
At one end of the rock-shaft at is rigidly attached a horizontal lever arm eª
provided with a slot f' into which projects a wrist pin ƒ mounted upon the face
of the disc c'
This disc c¹ is secured upon a shaft c³ mounted in bearings g¹ and provided with
a worm wheel c' engaging with the screw b³. A pulley 6 is attached to the screw
shaft and receives motion for any convenient driving shaft The rotation of the
screw by means of this pulley be causes a slow revolution of the worm wheel c' and
disc c and by means of the pin f, and slot frocks the shaft a' and lever arm d³
thus slowly reciprocating the shaft D lengthwise.
The arrangement of the blank upon the removeable plate E permits the operator
to examine them af any moment by tilting the plate backward or even to
remove the plate and insert another containing new blanks without stopping the
machine
The advantages of tho various adjusting devices need not be particularized as
they will be obvious to one skilled in the use of such machinery, and their several
modes of operation have been fully explained above
I claim
First. The combination with the grinding device of a blank holder, and a
reciprocating frame adapted to receive and secure said holder but open at the back
(or side which is farthest from the grinding device) to permit the insertion and
removal of the blank holder through the frame, substantially as set forth
Second. The combination with the reciprocating frame, and its removeable blank
holder, of the roller P. adapted to bear against said frame adjacent to, but clear of
the blank holder., substantially as set forth.
Third The combination of the sliding pillow blocks, of the grindstone shaft, with
the screw connections o o¹ and the hand wheel shaft m said screw connections and
hand wheel shaft being provided with bevel gears separately adjustable therein,
whereby said pillow blocks can be jointly as well as separately adjusted by means
of said hand wheel shaft.
Fourth. The combination of the sliding carriage Q, of the bearing rolls, with the
screw rods P. and hand wheel shaft m, said screw connections and shaft being
provided with bevil gears separately adjustable therein, whereby said carriages
can be jointly as well as separately adjusted by said shaft.
Fifth. The combination of the. grindstone shaft D. the lever arm engaging
therewith the rock shaft a' and means substantially as specified whereby said rock
shaft is oscillated
Sixth The combination with the grind-stone of the dressing device C' and shaft A³
reely supported in bearings A' said bearings being adjustable with reference to
he grindstone surface. substantially as specified
In witness whereof I the said Alfred George Brookes have hereunto set my
and and seal this Seventh day of November in the year of our Lord Ono
housand eight hundred and eighty three.
ALEDED
ABODAD TRAV
ALFRED
GEORGE BROOKES
(L.S.)