Improvements in Apparatus for Grinding the Knives or Cutters of Mowing-machines.
Year: 1889

page_text: [Communicated from abroad by RUFUS DUTTON, of the City and State of New York,
United States of America, Manufacturer.]
Improvements in Apparatus for Grinding the Knives or Cutters of
Mowing-machines.
I, HENRY HARRIS LAKE, of the firm of Haseltine Lake, and Co., Patent Agents,
Southampton Buildings in the County of Middlesex, 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 been devised with special reference to machines embodying
more or less of the several improvements described in the specifications of British
Letters Patent No. 7030 of 188, and No. 4312 of 1887, and one object of the present
invention is to reduce to a minimum the bulk and weight of such forms of machines
as are organized for field service without impairing their effective strength and dura-
bility and this has been so far accomplished that the present machines weigh only
about five-eighths as much as the first which were made for field service. A similar
reduction in bulk has also been attained, but this is due largely to a re-arrangement
of parts of the machine, and as a result of these reductions in bulk and weight, the
cost of construction has been materially lessened, as well as the cost of boxing, freight
and handling.
Another object of the present invention is to place the points of contact between
the grinding surface and a knife more completely beneath the eye of the operator,
than is possible in the use of the said prior field machines, and this I have accomplished
by a re-organization of the gearing and grinding wheel crank and lever with the
mechanism by which said wheel is reciprocated while revolving said crank and lever
being now so arranged that the operator can stand facing one side of the grinding
wheel, and over the knife clamps instead of at the rear thereof, and facing the edge of
the wheel remote from said clamp as with my prior field machines.
Various other minor advantages accrue from the present invention, as will herein-
after be described

page_text: In the accompanying drawings
Figures 1 and 2-Sheet 1-illustrate one of the improved machines in its most
approved form, in side elevation and in top or plan view respectively.
Figure 3 illustrates the same in a view at the side opposite to that shown in
figure 1.
Figure 4 illustrates a portion of the same in end view.
Figures 5 and 6 in side and end views illustrate the upper portion of the grinding
wheel frame or wheel arm detached.
Figure 7 in two views illustrates the lifting hand lever by which the grinding
wheel is reciprocated.
Figures 8 and 9 illustrate respectively in side and top views the lower or base
portion of the grinding wheel frame.
Figures 10 and 11 illustrate in side and top view a pivoted stop plate detached from
the machine.
Figures 12 and 13 illustrate inside and top views a portion of the base clamp and
its frame.
Figures 14 and 15 are end and side views of the knife clamp.
Figures 16, 17 and 18 illustrate the grinding wheel in side view, section, and edge
view.
Figure 19 illustrates the gearing in section.
Figure 20 illustrates in side elevation one of the improved machines in a modified
form.
Figure 21 is a top view of a base clamp detached from the machine, figure 20.
Figure 22 is a top view of the base portion of the knife clamp frame of said
machine.
Figure 23 and 24 are respectively top and side views of a portion of a base clamp
adapted for use in machines otherwise like that shown in Figure 1 as a partial
substitute for the parts shown in figures 10 to 13 inclusive.
Figure 25 illustrates in side view a machine embodying portions of the present
improvements but adapted to be permanently mounted upon a mowing machine.
Figure 26 is an end view generally corresponding to Figure 4 but illustrates a
hand lever and link as a grinding wheel lifting device, in lieu of the segment gear
lever and rack shown in said Figure 4.
The grinding wheel A in each of the forms of machine shown has a flat grinding
face at its periphery an interior water chamber and a feed duct and it is provided
with a hollow flanged axial hub, and is mounted on a non-rotative shaft a substantially
as heretofore used by me, and as disclosed in my aforesaid prior Patents.
I will first describe the form of machine illustrated in Figures 1 to 19, inclusive.
In this machine, the wheel frame is composed of two main parts B and B. The
lower part B serves as the base portion of the wheel frame, and is in the form of a
supporting bracket, which is swivelled or pivoted so as to swing to and fro laterally.
The upper part B is that in which the grinding wheel is partially enclosed and
directly mounted and it serves as a wheel arm to which vertical motion is imparted
for affording the requisite reciprocation of the wheel while grinding a mower knife.
These two parts of the wheel frame are united in a novel manner so that while both
I can be swung laterally as one frame to and fro on its pivot, the wheel arm portion
can be moved up and down carrying the grinding wheel. The base portion of the
frame has two parallel vertical guide bearings band to these the sides 6 of a flat tail
piece are accurately fitted. This tail piece 62 has on its rear side a spline or web b³
which occupies a vertical central groove 6 in the front face of the base portion B of
the wheel frame as clearly indicated in Figures 5 and 9. This combination of the
tail piece having a central web, and the wheel frame base having a central groove
and also having the guide bearings for the sides of the tail piece enables desirable
results to be obtained at little cost in machinery, it being obvious that the central
web will only require the fitting of its two edges to its groove to secure the tail piece
against lateral or edgewise displacement and that the sides of the tail piece, need
only to be ground for properly occupying the guides b without providing for a

page_text: bearing contact of the edges of the tail piece in said guide bearings. At the top of
the wep 63, there is a shoulder which limits the downward movement of the wheel
frame arin, by abutting upon the top edge of the base portion B of the wheel frame.
The wheel frame arm with a tail piece thus constructed and provided with guide
bearings as described is truly guided during its reciprocating movements and with a
minimum of friction at the several points of contact and the said arm with all its
parts can be readily detached from the rest of the machine. In this machine said
reciprocating movoment is effected by means of a hand lever c, a segmental gear
c¹
thereon and a rack gear c on the back of the tail piece 2, the lever being pivotted
upon a stud c, projecting angularly from the base portion B of the wheel frame,
and its gearing is so arranged that said lever stands out at one side of the machine in
a position convenient for manipulation during the grinding operation.
The grinding wheel is driven by the hand crank & attached to the hub of a bevelled
driving gear d which meshes with a bevel gear d², integral with or on the hub of a
larger gear 3, which in turn meshes with a smaller gear on the flanged hub of the
grinding wheel A.
The gearing organized as indicated is usually arranged to afford
nine or ten revolutions of the grinding wheel to each revolution of the crank.
The driving gear dis mounted at right angles to the axis of the grinding wheel
on a stud d and the gears d2 and d³ are mounted on a stud de parallel with said
axis both of said studs projecting from the wheel arm portion B' of the frame, and
standing at right angles to each other. The non-rotative shaft a on which the
grinding wheel A and gear are mounted is supported on portions of the frame
which are in the same horizontal plane as that occupied by the studs d³ and do.
This combination of the grinding wheel, the frame arm, and the crank standing at
right angles to the axis of the wheel, and with the gearing and crank mounted on
studs projecting from said frame arm, is of practical value as a novel feature of
construction, not only with reference to compactness and economy but also with
reference to assembling the parts and mounting them as a whole in a machine or in
readily transferring them from one machine to another in the event of such breakage
of both as would render a reassembling of parts desirable.
The base clamp frame C by which the machine can he readily mounted upon a
mowing machine for service in the field is substantially as heretofore having the
same fixed jaws e movable jaws e and thumb nuts e. The wheel frame is pivoted
to this base clamp frame as follows: Between the base clamp frame C, and the base
portion B of the wheel frame an adjustable stop plate f is interposed, and this plate,
as in one form of the prior machines also serves as the coupling medium between the
wheel frame and the base clamp frame. Said stop plate at one end is pivotted at f
Figures 10 and 11 to a cross bar e Figures 12 and 13, so that its opposite end may
swing in a horizontal plane and at the said opposite end said stop plate has a vertical
hollow hub or sleeve f. The wheel frame base B-Figures 8 and 9 is bored to
receive a pivot bolt & (see Figure 1 and also shown in dotted lines in Figure 8) and
said bolt in said sleeve couples the wheel frame to the base clamp thus providing
for a double pivotal connection, one pivotal point being at the junction of the wheel
frame base with the stop plate and the other being at the junction of the opposite
end of said plate with the base clamp frame.
Upon the wheel frame base B there are two stop abutments g and on the stop plate
there are stop faces g' which by engagement with said abutments limit or restrict the
swivelling movement of the wheel fraine with relation to the stop plate. At each side
of the base clamp there is a lateral adjusting screw g², and these by engaging at their
inner ends with the coincident surfaces of the stop plate variably restrict the swivelling
movement of said plate with relation to the base clamp frame or other foundation of
the machine. These stops gg' are provided with thumb latches ³ which lock the
wheel frame in either position of adjustinent according to which pair of the stops
may be in contact.
This feature of varying the position of the pivotal point of the wheel frame, is of
"practical value only for enabling a variety of bevels to be ground as when operating

page_text: upon a mower knite previously irregularly ground, and therefore an adjustable stop
plate need not be always employed in my machines.
The knife clamp frame D, see Figures 14 and 15, has a hollow sleeve h by which,
and a horizontal rod or shaft it is hinged by a horizontal pivot on the base clamp
frame (see Figure 1) and said sleeve has an arm / which projects toward the wheel
frame, and is laterally notched as at 3, for the reception of a finger h4, which extends
from the wheel frame base, and occupies said notch, whenever said arm and finger
occupy the same line, as when the machine is not in service. Said arm also serves
as a lever, to which one end of a retractile spiral spring i is attached, its opposite end
being coupled to an adjusting screw passing through a pendant bracket 2 on the
wheel frame base, and provided with a thumb nut i³.
It will be seen that the knife clamp E is normally inclined toward the face of the
grinding wheel and also that the guide bearing in which the frame arm slides, is
inclined toward the knife clamp, and therefore as the wheel is raised for grinding
toward the tip of a knife edge the clamp is forced rearward and the force of the
spring increased, thus enabling the tips to be ground under an abrasive pressure equal
to if not slightly greater than when grinding at or near the bottom of the V between
any two knife sections.
The knife clamp E is in all essentials the same as that described in the specification
of the aforesaid Letters Patent No. 4312 of 1887 and hence needs no special
description of its two pairs of clamping jaws and gauging belt k². It will be
understood that a mower knife is mounted in said clamp with the rear edge of the
knife downward and its blades or sections standing upward in a nearly verticle
position and when properly adjusted for grinding the centre of the head of the
gauging bolt 2 is opposite the bottom of a V between two adjacent knife sections a
notch on said bolt head serving as a gauge point. One or the other or both of the
two pairs of clamping jaws are caused to firmly grip such portions of the knife as
may be interposed between their clamping faces.
The spring i in this machine, forces the knife clamp toward the face of the grinding
wheel in a manner similar to the corresponding spring shown in said Letters Patent
No. 7030 of 1886 and it is without such means for directly varying its power during
the rise and fall of the grinding wheel so as to cause heavier grinding contact at the
tips of mower knives than at their bases as described in the specification of the said
Letters Patent 4812 of 1887, but I produce somewhat like results to a satisfactory degree
by the inclination of the guide bearings of the base portion B of the wheel frame
hereinbefore described. It will be readily seen that the main features of my invention
are not dependent upon the inclination of the wheel arm toward the knife clamp this
latter being a feature involving a nicety in operation, which many operators will fail
to readily appreciate.
Now referring to Figures 1 and 2 it will be readily understood that an operator
facing one side of the grinding wheel can operate the driving crank with his right
hand and while manipulating the lifting lever with his left hand, he will be able to
place his head so directly above the knife clamp that he may closely observe every
part of the grinding operation and thus to enable him to obviate undue abrasion at
any point on a knife edge requiring but little grinding and to avoid stopping the
machine from time to time for enabling observation at those points where heavy
grinding should occur as when working out gaps or notches. It will also be seen that
even when the machine is ready for service, it is very compact, so that in fact such
machines occupy a space but little greater than a cubic foot, and when the crank, the
.hand lever, and the knife clamp are disconnected and arranged for packing, much
less than a cubic foot of space will be occupied by the machine.
It will also be observed that as in the prior machines, the wheel frame is so hinged
or pivoted with relation to the knife clamp that the centre of motion is within the
flat faced grinding wheel, and that therefore the two adjacent edges of any two knife
sections can be consecutively ground without changing the position of the knife in the
clamp, and thereby securing uniform bevels at the ground edges in accordance with

page_text: the said Letters Patent No. 7030 of 1886 and also that the adjustable stop plate in
this machine, enables uniform bevels to be ground.whenever practicable, while enabling
knives which have been previously irregularly ground to be ground at such bevels as
may be best suited in each case, all in accordance with the said letters patent No. 4312
of 1887.
In certain forms of the machine, organized with reference to a minimum cost, but
at a consequent sacrifice of more or less of the desirable capacities of the better
forms of machines, I construct the stop faces g' integrally on the base clamp frame C,
as shown in figures 23 and 24.
It must not be supposed that the advantages incident to a sliding frame arm for
the wheel and the system of gearing described will only accrue if restricted to a
form of machine in which the wheel frame is pivoted to swing laterally because
in one form of the machines preferred by some operators the grinding wheel frame
is non-pivotal as illustrated in figures 20, 21 and 22. In this form of machine the
grinding wheel A and its frame arm B are precisely as in figure 1 and the same
is true of the lifting levere the driving gearing, and the knife clamp E. The knife
clamp frame is also the same at the part D, but this instead of being pivoted to the
base clamp frame is pivoted to one end of an extension D₁ of said knife clamp
frame which at the opposite end has a sleeve ³ occupied by the pivot bolt 66 so that
the knife clamp and its frame can be swung to and fro laterally on said pivot.
base portion B of the wheel frame is in this case rigidly attached to or formed
integrally with the base clamp frame C, as is clearly indicated in figure 21 and the
stop faces are therefore formed on the part D¹ of the knife clamp frame, so as to
engage with the abutments on the base portion B of the wheel clamp frame.
The
I have found it desirable to embody the main portions of the present invention in
a specially cheap but effective form of machine, adapted to be mounted as a fixture
on mowing machines and reapers and to be sold therewith.
In figure 25 I show such a machine wherein a simple base plate C₁ takes the
place of the base clamp frame and this is permanently secured by a bolt to a pole
or other desirable portion of a mowing machine. The knife clamp E is as before
described, although only partially illustrated here for better disclosing the knife clamp
spring and its adjusting screw 1. The base plate has a sleeve m occupied by the
bolt which pivotally unites the base portion B of the wheel frame thereto, this latter
part of the wheel arm portion B¹ the wheel A, the gearing, and the driving crank,
being substantially as before described, but no lifting lever is here employed, because
a simple laterally projecting handle is relied upon for raising and lowering the
grinding wheel, and instead of such a handle, a mere hand loop can be successfully
employed, as is indicated in dotted lines in figure 5, on top of that portion of the
wheel frame arm B' which overlies the grinding wheel and serves as a shield.
avoidance of a hand lever is only of material consequence when the grinding machine
is to be permanently mounted at such points on a mowing machine as will render it
inconvenient or impracticable to operate a lever, as when the space requisite for said
lever is not available.
This
While the hand lever with the segmental gear, and the rack on the wheel arm
portion of the frame, is preferred by me on account of its simplicity, and cheapness I
obtain good results with a lever and a link, as illustrated in figure 26 wherein the
lever c has a simple straight end c³, which is coupled by a link, c to the wheel arm
portion of the frame B', which has therefore no rack gear thereon.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed as communicated to me by my
foreign correspondent, I wish it understood that I claim in a mower knife-grinding
machine,
First. The combination substantially as herein before described of a flat-faced
grinding wheel, a knife clamp, a knife clamp frame, and a grinding wheel frame, said
frames being pivotally coupled with relation to each other to provide for lateral
swinging adjustment and said grinding wheel frame being composed of two parts one

page_text: serving as an arm in which the wheel is mounted and sliding in said other part or
base portion of said frame, à driving crank mounted on a pivot on said arın portion
of the frame at right angles to the axis of the grinding wheel and gearing also mounted
on said arm portion of the frame for rotatively coupling said crank with the grinding
wheel.
Second. A flat faced grinding wheel, a pivoted knife clamp normally inclined
toward the grinding face of said wheel, a spring forcing said clamp toward the
grinding surface, and a sliding frame carrying said wheel and mounted in guide
bearings, which are inclined toward said knife clamp, substantially as described,
whereby as the grinding wheel is lifted by the sliding movement of its frame, it will
also be advanced toward a knife held in said clamp, and by forcing the latter
rearward, increase the force of said spring, and thus enable the tips of a knife edge
to be ground under abrasive pressure equal to that afforded while grinding the lower
portion of the same edge.
Third. The combination substantially as described, of a knife clamp, its frame, a
flat-faced grinding wheel and its frame the latter being constructed in two parts,
one sliding upon the other, a driving crank standing at right angles to the axis of
the grinding wheel and coupled to said wheel by gearing, and a lever for lifting and
lowering that portion of the wheel frame in which said grinding wheel is directly
mounted.
Fourth. The combination of a knife clamp and a flat faced grinding wheel, both
mounted in frames which are pivotally connected to admit of lateral swinging
adjustment, stops for restricting said pivotal movement and latches which confine or
lock said stops when in position for service, substantially as described.
Fifth. The conibination with the grinding wheel, of a detachable wheel frame arm
in which said wheel is mounted, a hand crank standing at right angles to the axis of
the wheel and mounted on a stud projecting from said frame at the rear of said
wheel, and gearing also mounted on studs projecting from said frame for coupling
the crank with the grinding wheel, substantially as described.
Sixth. The combination, substantially as described, of the knife clamp the grinding
wheel, the sliding wheel frame arm provided with a tail piece having a rack gear
thereon, and a hand lever having a segmental gear engaging with said rack gear for
lifting and lowering said grinding wheel while its face is in contact with a mower knife
held in said clamp.
Seventh. The combination of the wheel frame arm having a flat tail piece provided
with a central spline or web, and the wheel frame base provided with a central
vertical groove for receiving said web, and also provided with guide bearings for
receiving the two edges of said tail piece, substantially as described.
Dated this 1st day of January 1889. ·.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C.,
Agents for the Applicant.