Improvements in Lawn Mowers.
Year: 1897

page_text: Date of Application, 18th Oct., 1897-Accepted, 27th Nov., 1897
COMPLETE SPECIFICATION.
Improvements in Lawn Mowers.
I SAMUEL PERCY TOWNSEND of Bloomfield in the County of Essex State of New
Jersey one of the United States of America Manufacturer of Lawn Mowers 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:
My Invention relates to improvements in lawn mowers, and the object of my
invention is to provide means by which the cutting reel in ay be driven from a
point or points between the ends without interfering with the cutting action
thereof, whereby a cutting reel of any desired width may be used, and the driving
and supporting mechanism of the mower may be disposed within the lateral limits
of the said cutting reel, in order to permit the latter to cut closer to fences, walls
or other obstructions than is possible in ordinary machines.
:
My invention consists in the constructions and combinations of parts hereinafter
described and illustrated by the accompanying drawings,
Figure 1 of which is a plan view of a lawn mower embodying my invention;
Figure 2 is a side elevation of the same with some of the parts broken away;
Figure 3 is a plan view of a portion of the reel drawn to a larger scale,
Figure 4 is a diagrammatic view of my improved form of gear;
Figures 5 and 6, are perspective views, of a diagrammatic character, illustrating
the application of my invention to different forms of reel from that shewn in
Figures 1, 2 and 3; and
Figure 7 is a diagram similar to Figure 4, but illustrating a modified form of
gear wheel.
Like parts are represented by similar letters of reference in the several views.
In the accompanying drawings a represents the frame and a¹ the driving
wheels which are mounted on a shaft a2 to which they may be connected by the
usual pawl and ratchet devices so that they will cause the shaft to revolve therewith
when moving in a forward direction but will turn independently of the shaft
when moved in a backward direction.
This shaft a² is supported in suitable bearings in the frame a, which frame also
supports the stationary cutter 6 and is provided with bearings for the cutter reel.
Mounted on the axle a² is a spur gear a³ adapted to mesh with a pinion at which
is formed integral with, or is connected with, what I term a "duplex segment gear."
This duplex segment gear is of peculiar construction and consists essentially of
two gears each formed in sections, the sections of each part being separated and
disposed opposite the spaces in the other part; that is to say, the gear is composed
of two series of toothed sections or segments d¹ d2 and said segments in each series
being separated from each other by spaces d³, the segments of one part being arranged
opposite the spaces between the segments of the other part. In the gear shewn in
the drawing, there is, at the end of each segment, a connecting bar d' which is

page_text: included in both parts of the gear and forms a tooth in a segment of each series, this,
however, is not indispensible as the segments of the two series may be entirely
disconnected if desired.
The cutter reel is made in two parts c¹ and c² the blades of each part being shewn
arranged so that the inner ends of each series of blades extend beyond the centre of
the reel and the two sets of blades overlap at this point, hence, in cutting, there is
no space in the length of the stationary cutter b which does not contact with the
blades c or c².
The blades might, however, simply extend to the central line of the reel without
overlapping.
On the reel shaft is arranged a duplex pinion which is preferably made in two
parts e¹ and e³ to engage with the respective parts of the duplex segment gear d¹ d².
The spaces ds in the latter are so arranged that as the gear revolves these spaces
permit the passage of the ends of the blades of the reel, while the sections of the gear
alternately drive the said reel through the medium of the two part pinion ei e², a
section of the portion d¹ of the gear being in mesh with the pinion e¹ when a blade
of the portion c² of the reel is passing through a space between the sections of the
portion d² of the gear, and vice versa.
It is obvious that two separate pinions e¹ and e2 may be employed if desired, both
connected to the reel shaft; or a single pinion having teeth long enough to mesh with
both series of sections in the duplex segment gear may be employed.
The reel blades may be supported on the shaft in any usual manner with the
inner ends of said blades projecting over the driving gear, as shewn. I preferably,
however, construct the pinion or pinions e¹ e² with projecting ears or lugs e³ which
take the place of the ordinary arms or spiders for supporting the ends of the reel
blades, as shewn in Figure 3, thus simplifying the construction of the reel.
I have shewn the mower herein described as a rear-cut mower, the handle f¹ (parts
of which are broken away), being connected to the main axle a². The frame a a is
also offset so that the driving wheels stand in front of the reel and within the lateral
limits of the same, thus securing a very long cutting surface of the said reel without
increasing the width of the machine, and permitting the cutting of the grass close up
to fences, walls, trees or other obstructions.
It is obvious, however, that the construction of the mower may be modified and
my improvements may be used upon a mower having either a front cut, or rear cut
as desired.
The usual roller g is adjustably secured to the frame a a so as to support the same
and determine the height of cut.
My improved gearing for driving the reel is not limited of necessity to a mower having
a reel with straight overlapping blades, for instance, in Figure 5 I have illustrated a
construction in which the reel has spiral blades continuous from end to end of the
reel, and in which the two parts d³ d4 of the duplex segment gear and the two
parts eet of the reel pinion are widely separated, so that one set of gears may be in
imesh between the blades at one end of the reel, while a blade at the other end of the
reel is passing through a space between the segments of the driving gear.
In Figure 6 I have shown a construction in which the section d5 of the duplex
segment gear is carried by a shaft independent of that which carries the section do
of the said gear, the two shafts being driven at the same speed and in the same
direction by means of the interposed train of gearing it, one section d³ of the
segment gear meshing with a pinion on the reel, and the other section do with
another pinion e thereon.
It will be evident that the term "duplex segment gear" includes the ordinary
form of waved or "wobble "gear, such for instance as shewn in Figure 7, as the latter
would act to drive the duplex pinion of the reel in substantially the same manner as
the rack shewn in Figure 4.
It is manifest, moreover, that certain teeth of each of the spur pinions are never in
mesh with the teeth of the segment gear and these non-acting teeth may, if desired,
be omitted for the purpose of lessening the weight of said pinions.

page_text: 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. In a lawn mower, the combination of a cutter reel having a duplex spur pinion
and a duplex segment gear, having one portion adapted to mesh with one part of
said duplex pinion, and the other portion with the other part of the same, the toothed
segments and spaces of said duplex segment gear being so arranged that when a
toothed segment of one section of the gear is in inesh with one section of the duplex
spur pinion, a blade of the reel will be passing through a space of the other section of
the segment gear substantially as herein before described.
2. In a lawn mower, the combination of a duplex segment gear having the toothed
segments of one section alternating with those of the other section, with a cutter reel
having a duplex pinion for meshing with the said duplex segment gear, and cutting
blades arranged in two series, the blades in one series alternating with those of the
other series substantially as hereinbefore described.
3. In a lawn mower, the combination of a duplex segment gear having the toothed
segments of one section alternating with those of the other section, with a cutter
reel having a duplex pinion adapted to mesh with the said duplex segment gear, and
cutting blades arranged in two series, the blades in one series alternating with those
of the other series, and the inner ends of the two series of blades overlapping,
substantially as herein before described.
4. In a lawn mower, the combination of a main frame, a cutting reel, main driving
wheels disposed within the lateral limits of the cutting blades of the reel, a duplex
segment gear connected to said driving wheels and having the toothed segments of
one section alternating with those of the other section, and a duplex pinion on the
cutter reel adapted to mesh with the said duplex segment gear, substantially as
hereinbefore described.
5. In a lawn mower, the combination of a cutter reel having the cutting blades
arranged in two series, the blades in one series alternating with those of the other, a
duplex pinion on said cutter reel, and a duplex segment gear for driving said pinion,
said duplex segment gear consisting of two series of toothed segments, those of one
segment alternating with those of the other, and the end teeth of adjoining
segments being united and forming a tooth common to both series, substantially as
herein before described.
6. In a lawn mower, the combination of a cutter having the blades arranged in two
series, a duplex pinion on said cutter reel having projections to support the inner
ends of each series of cutting blades, and a duplex segment gear having the toothed
segments of one section alternating with those of the other, the said duplex segment
gear meshing with the duplex pinion of the cutter reel, substantially as hereinbefore
described.