IMPROVEMENTS IN AND APPERTAINING TO LAWN MOWING MACHINES
Year: 1879

page_text: PROVISIONAL SPECIFICATION left by William Phillips Thompson at the
Office of the Commissioners of. Patents on the 26th February 1879. A com-
munication from abroad from Phineas Mast and Samuel Webb Martin, both of
Springfield, Clark County, Ohio.
.
WILLIAM PHILLIPS THOMPSON, of 6, Lord Street, Liverpool, in the County of
Lancaster, and 323, High Holborn, in the County of Middlesex, British and
International Patent Agent. "IMPROVEMENTS IN AND APPERTAINING TO LAWN
MOWING MACHINES." A communication from abroad from Phineas Mast and
Samuel Webb Martin, both of Springfield, Clark County, Ohio.
This Invention relates to that class of lawn mowers in which spiral revolving
knives are arranged to act in conjunction with a fixed blade, and the Invention
consists in a peculiar manner of constructing the frame, in a special arrangement of
gearing, in the manner of sustaining and adjusting the fixed blade, in a folding
grass receiver, and in other details of construction hereinafter described.
1st. In constructing the machine I provide a main frame consisting of two vertical
side plates connected by cross connections.
Each frame plate has on the outside a horizontal journal or trunnion on which
there is mounted an internally main geared wheel, and also outside of said wheel
an independent driving wheel to run upon the ground.
The two ground wheels are assisted in sustaining the main frame by two smaller
wheels or rollers attached by adjustable arms to the rear end of the frame. The
main gear wheels have their discs or bodies made solid without spokes or openings,
and have the overhanging edges of their geared rims arranged to fit closely against
the outside of the frame plates which are provided with projecting annular
flanges to surround them and exclude the grass and dirt from the gear teeth. As a
means of driving the main gear wheels they are each provided near the centre with
transverse sliding pins seated in holes and urged outward by springs so as to
engage at their ends with ratchet teeth on the inside of the ground wheel. In order
to protect these parts from dirt, et cetera, the hub of the ground wheel is adapted to
fit over that of the gear wheel. In order that the ground wheels may at all times
engage upon a slight forward movement each one is provided with four ratchet
teeth, and each gear wheel provided with two of the clutch pins so arranged as not
to be diametrically opposite each other; the effect is that each wheel is caused to
lock at eight points in the course of a revolution instead of at four only, as would
otherwise be the case.
2nd. I provide a rotary cutter head consisting of a series of spiral blades secured
to end plates or discs which are mounted on a transverse shaft, the ends of which are

page_text: extended through the side plates and bearings thereon, and provided with pinions
which gear into and are driven by the main gear wheels, which also serve to conceal
and protect the pinions. The blades of the rotary head act in conjunction with a
fixed transverse blade which is attached to and sustained by a rocking plate the ends
of which are seated on studs on the lower edge of the frame, and secured by screws
passing through the plate into the frame. By tightening the screws at one side of
the plate and loosening those at the other the plate may be given a rocking or rolling
adjustment, so as to elevate or depress the transverse blade and bring it in the proper
relation to the rotary blades. The edge of the fixed or transverse blade should be as
low as the lowest point to which the rotary cutters descend, so that the latter shall
not exert any upward strain or pulling action in severing the grass. The plate or bar
which sustains the fixed blade also serves as one of the cross braces of the frame,
thus avoiding the use of extra parts and leaving an unobstructed outlet for the
grass. The upper brace of the frame consists of a piece of gas pipe or tubing of the
proper length seated at its ends in sockets cast in the side plates, and of a rod or
bolt passed through the centre of the tubing and out through the side plates, and
tightened up by means of a nut or nuts on its ends so as to force the plates firmly
against the ends of the tube. The arms to which the rear sustaining rollers aro
attached are curved and slotted in the arc of a circle, and are seated between flanges
on the outside of the frame plates and secured by a bolt or screw, so that they may
be readily adjusted to vary the height at which the grass is cut. As a means of
propelling the machine it is provided with a handle having forked arms which are
mounted on studs cast on the inside of the frame plates and limited in their vertical
play by studs also formed on the plates.
In order to render the machine as narrow and compact as possible, and to
prevent the ground wheel from running over upon the uncut grass further than is
necessary, the ground wheels are dished and have their spokes and rims thrown
inward.
I provide the machine with a receiver which is not only capable of being
readily applied and removed but which may be folded at will into a very small
compass, in which condition it adds nothing to the size of the machine. This
receiver consists in a cloth or canvass bag open at the front and top, and sustained
by means of a front frame and a top frame, both made of wire and sewed into the
edges. The frame has its lower edge seated in a groove in the knife supporting
plate, and bears at its sides against studs on the sides of the main frame, while the
top frame of the receiver, which is jointed to the top of the side frames of the
receiver nearest the cutters, is provided with a bail which is engaged with a tooth
bar secured to the handle of the machine. This arrangement retains the bag or
receiver in an open or expanded position in such relation to the machine that the
grass is thrown directly into it. The disengagement of the bail releases the receiver
and admits of its being readily removed to discharge the grass. When detached
the receiver may be folded into a very compact form and the machine packed in the
same compass that it would occupy without the receiver. If desired the receiver
may be modified in form and in the construction of its frame, and the body or bag
made of rigid plates hinged or jointed together in such manner as to be capable of
folding into a compact form.