Improvements in Lawn Mowers.
Year: 1893

page_text: Date of Application, 22nd Aug, 1893-Accepted, 23rd Sept., 1893
CUSIF LETE DI ECIFICATION.
Improvements in Lawn Mowers.
1, HENRY DECK, of 1615 North Twenty-third Street, Philadelphia, in the
County of Philadelphia, State of Pennsylvania, United States of America,
Machinist, do hereby declare the nature of my invention and in what manner the
same is to be performed to be particularly described and ascertained in and by the
following statements :—
It is the object of my invention to produce a lawn mower of improved con-
struction.
A part of the features of improvement relates to the manner of supporting the
shaft of the rotary cutter blades whereby it may be readily adjusted in position,
and permitted to automatically adjust itself to any irregularities or unevenness in
the stationary or ledger blade. By this means the blades of the rotary cutter
may be caused to make constant contact with the edge of the stationary knife to
produce the most effective cutting action, without danger of jambing or undue
friction, and the slight friction between the blades produces an automatic sharpening
of the cutting edges.
Another portion of the invention relates to the manner of supporting the shaft of
the rotary cutter so that it may be easily removed from the machine for purposes
of repair.
My invention also includes improvements in the construction and manner of
supporting the stationary or ledger blade, and also other combinations and
arrangements of parts which are hereinafter more fully described and claimed.
In the drawings:
Fig. 1 is a plan view of the cutters and operating mechanism of my improved
lawn mower;
Fig. 2 is a transverse vertical sectional view of the same on the line x-x of
Fig. 1;
Fig. 3 is a transverse vertical sectional view on an enlarged scale of the dead or
ledger knife and its supporting bar;
Fig. 4 is a longitudinal sectional view of the same on the line y-y of Fig. 2 on
an enlarged scale ;
Fig. 5 is a longitudinal vertical sectional view of the supporting and driving
devices of the shaft of the rotary cutter on the line --z of Fig. 2 on an enlarged
scale;
Fig. 6 is a side elevation of one of the detached journal boxes of the shaft of the
rotary cutter ;
Fig. 7 is a transverse vertical sectional view of the same on the line w-w;
Fig. 8 is a perspective view of one of the detached journal box bearings; and
Figs. 9 and 10 are detail views in perspective of a portion of one of the side
frames and locking devices for the rotary cutter shaft.
A are the wheels of the lawn mower, by the rotation of which the shaft of the
rotary cutter is driven.
B is the rotary cutter of the usual construction.
C is the shaft of the rotary cutter.
D are the side frames of the machine by which the cutting mechanism is carried.
His the stationary cutter or ledger blade.
It is immaterial to my invention in what particular manner the shaft C of the
rotary cutter is driven from the wheels A; and any convenient form of power
transmitting devices may be employed. For the purpose of illustration, however,
I have shown in the drawings driving mechanism, consisting of the internal annular
gear L carried on the inner side of the wheels A, and gearing with a pinion M
Price 8d.1

page_text: sleeved on the end of the cutter shaft C, the pawl N carried by the shaft C, and
the ratchet P on the pinion M, whereby the pinion M drives the shaft C, when
rotated in one direction, but not in the other.
I shall now describe the features of my invention so far as they relate to the
manner of supporting and adjusting the cutter shaft C in the frame of the mower.
The side frames D are provided with open notches d (see Fig. 9) preferably
inclined in which the ends of the shaft C are inserted. These notches permit an
easy removal of the cutter shaft from the side frames whenever it may be desired
for the purpose of making repairs. These notches are preferably larger than the
diameter of the shaft so as to permit the shaft to play in them for the purpose of
adjustment.
D' are plates adapted to be secured to the side frames D to close the openings in
the notches and prevent the passage of grass to the shaft C. The plates D' may
be provided with heads or lugs d' adapted to fit down into the notches and
effectively close the opening to the shaft. The plate D¹ may be easily detached
when desired so as to permit the removal of the shaft C.
E are journal boxes in which the shaft C is journaled. These boxes are in the
form of sleeves placed over the ends of the shaft C and supported by the frame D
from lugs by means of adjustable screws E¹. The bearing surfaces of the
boxes E may be lined with babbit metal. The lower portions of the boxes E
are provided with recessed lugs e to receive the rounded ends of the lower
screws E. The recesses in the lugs e may be made round so that the box may
move on the rounded end of the screw E¹, forming a ball and socket support. The
upper portions of the boxes E are supported by the upper screws E', through the
intermediate blocks F and the springs G. The boxes E are provided with curved
ridges e, which are received in grooves f of the curved under surfaces of the
intermediate blocks F, and the ends of the upper screws E are received in recessed
collars of the blocks F. The ends of the screws E' may play slightly up and
down in the recessed collars 2 and the springs G are arranged between the blocks F
and the screws E. Fare washers which may be placed upon the upper screws E
resting on shoulders e* thereof, to form bearing surfaces for the upper ends of the
springs G.
Through this construction the cutter shaft C is supported in yielding bearings so
that it may move slightly towards or away from the ledger knife and thus
automatically adjust itself with reference to the knife. Through the adjusting
screws E which support the journal boxes the shaft C may be positively adjusted
with reference to the ledger knife so that the spiral cutting blades of the rotary
cutter B may just make contact with the edge of the ledger blade H, and the
shaft C being free to yield through the springs G, the edges of the rotary cutting
blades b may be kept in contact with the stationary or ledger blade H, yielding to
any inequalities or unevenness therein. By this means a more perfect cutting
action is obtained and the blades are kept sharpened by the friction of their edges.
The blades are thus self sharpened.
By the adjustment of the upper screws E', it is apparent that the tension of the
springs G may be adjusted to regulate the freedom of the shaft to yield.
1
The ball and socket support of the lower portion of the boxes E and the upper
support through the curved ridges e and intermediate grooved blocks F permits
slight movement of the boxes E at each end of the shaft C, so that the shaft may
more easily adjust itself automatically. This construction will permit one end of
the shaft to move to a greater or less extent than the other.
Another part of my invention relates to the construction of the ledger blade H
and the manner of supporting it in the machine.
I is the stationary knife bar which carries the ledger blade H. Instead of
riveting or screwing the blade H to its supporting bar I, I prefer to cast the
supporting bar I upon the steel blade, as shown in Figs. 2, 3, and 4 of the
drawings. The blade may be of the usual construction provided with a series of
perforations and when the bar I is cast upon it, the metal flows through the

page_text: perforations h and the bar I becomes firmly secured to the blade substantially as if
made of one piece with it. The bar I is provided with flanges J at its ends by
which it may be attached to the side frames D through a bushing J¹ and bolt J*
and nut j. The bushings J' form the bearings for the bar I and permit it to be
readily disconnected from the side frames D. The bar I may be adjusted upon its
bearings to move the blade H to proper position with reference to the rotary
cutter blades 6 through the projecting arms k, which are acted upon by two set
screws carried in lugs of the frame D (see Fig. 2).
The bushings J' have the flanges which bear against the outer faces of the side
frames D and take the place of the usual washers.
The use of the bushings J as the bearings for the ends of the bar greatly
reduces the wear and permits the bar I to be more easily disconnected.
K is the usual guide roller carried by extensions of the side frames D and
located in the rear of the machine behind the stationary or ledger blade H.
The lawn mower may be provided with the usual handle.
While I prefer the minor details of construction shown, I do not mean to limit
myself to them, as it is apparent that they may be varied without departing from
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 1 declare that what I
claim is :-
First. A lawn mower having its rotary cutter shaft journaled in automatically
yielding bearings.
Second. A lawn mower having the shaft of its rotary cutter journaled in the
independent journal boxes carried by the side frames.
Third. The independent journal boxes for the side frame supported by the upper
and lower adjusting pins.
Fourth. The independent journal boxes for the side frame having the lower ball
and socket supports and the upper yielding supports.
Fifth. The notched side frames to receive the ends of the rotary cutter shaft
beyond the independent journal boxes.
Sixth. The detachable plates D' for closing the open notches & in the side
frames.
Seventh. The cutter bar J cast on the ledger blade.
Eighth. The bushings J¹ and bolts J' for connecting the cutter bar with the side
frames.
T..1 1002
Dated
21st day of July
1009
HENRY DECK.
Haseltine, Lake & Co.,
45, Southampton Buildings, London, Agents for the Applicant.