Improvements in and connected with Endless Aprons of Reaping Machines.
Year: 1889

page_text: Date of Application, 28th Oct., 1839-Accepted, 30th Nov., 1889
COMPLETE SPECIFICATION.
Improvements in and connected with Endless Aprons of Reaping
Machines.
I, THOMAS SOUTAR BISSET, of Blairgowrie, in the County of Perth, North Britain,
Agricultural Engineer, 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, that is to say :-
My said Invention relates to endless aprons such as are used on reaping machines
fitted with binding mechanism for moving the crop across the platform and for elevating
it at the side; and my object is by improved an I simple devices to overcome certain
defects and inconveniences of such aprons as hitherto made and arranged.
It has been common to join the ends of the canvas forming an endless apron by
means of straps and buckles together with an overlapping flap secured by lacing.
The straps and buckles do not run smoothly round the necessarily small rollers, and
considerable tension has to be put on the apron requiring greater driving power than
ought to be required. Amongst other inconveniences is the fact that canvasses joined
in the manner referred to cannot be reversed in position for the purpose of equalising
the wear which always takes place mostly at and near the edges which are to the front
in working.
I carrying out my Invention I join the ends of a canvas by fixing together by
screws faths which are riveted or otherwise fixed to the extreme end edges of the
canvas; and I provide for maintaining the canvas or apron in a properly stretched
state by devices for adjusting one of the rollers which carry the apron at a greater or
less distance from the other roller, such devices being easily adjustable from the outside
without unfastening any part, being provided with springs which compensate for
differences of tension caused by the apron being more or less dry.
And in order that my said Invention and the manner of performing the same may
be properly understood I hereunto append a sheet of explanatory drawings to be here-
inafter referred to and representing my improved devices.
Figure, 1, of the drawings is a vertical section showing the pair of elevating aprons of
a self-binding reaper together with a small part of the platform apron. Figure, 2,
is an elevation corresponding to figure, 1, but as with one of the elevating aprons
removed. Figure, 3, is a plan of a portion of an apron showing the mode of joining
its ends and figure, 4, is a sectional detail view. In these drawings the same reference
numerals are used to mark the same or like parts wherever they are repeated.
In the case of each elevating apron, à, the journals of the upper roller, 6, are held
in bearings formed in the ends of bars, 7, bolted to the frame cheeks, 8. The journals
of the lower roller, 9, are held in bearings formed in the ends of bars. 10, secured to
the frame cheeks, 8, by bolts which pass through slots, 11, in the bars these slots
allowing the bars to move endways. The movable bearing bars, 10, are pressed on by
arins of bellcrank levers, 12, which are centered on brackets, 13, fixed to the fixed
bearing bars, 7. One of the hellcrank levers, 12, is connected by a rod. 14, to the
other one which has jointed to it a short rod, 15, made with a flattened inner end
having eyes for the lever joint pin and for the connecting rod, 14. The short rod, 15,
passes through the frame cheek, 8, and has on it outside the cheek a helical spring, 16,
which can be more or less compressed by means of an internally screwed hand
wheel, 17, fitted to a screwed part of the rod. By screwing up the handwheel, 17,
more or less, more or less spring pressure is applied to the rods, 15, 14, and through
them to the bellcrank levers, 12; and these levers by their arms bearing on the inner
ends of the movable bearing bars, 10, cause the lower roller, 9, to distend the
apron, 5.

page_text: Devices like those described for the elevating aprons, 5, are used for distending the
platform apron, 18, although not shown in the drawings.
Instead of placing and connecting the bellcrank levers, 12, as hereinbefore described
and as shown in the drawings, a rocking spindle or shaft may be arranged to extend
across from one frame cheek, 8, to the other, lever arms being fixed on it to bear on
the inner ends of the movable hearing bars, 10, and another lever arm being fixed on
it outside of one of the frame cheeks, 8, and having a spring and adjusting screw
applied to it. Or any other equivalent device for the same purpose may be used if
provided with external adjusting mechanism.
The aprons, 5, 18, have laths, 19, fixe.! across them at intervals, as is usual, to ensure
the moving of the crop by the aprons. I arrange these laths so as to have two, 20, at
the joint edges of the apron, and I join the edges of the apron together by uniting the
edge laths, 20, by screws which are indicated by dotted lines in figure, 3. With this
improved joint the apron passes easily and smoothly round its carrying rollers, and it
can be driven with moderate power without being very tightly stretched. The
improved apron can also be at any time reversed in position without making any
difference in its action, whilst its wear is thereby equalised, and its durability increased.
I prefer to make the joint laths, 20, in two or more short lengths; and the other
laths, 19, may also be made in short lengths, instead of in single lengths extending
across the apron.
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. The combination of endless aprons for reaping machines with mechanism for
regulating the distance apart of the carrying rollers and with external spring devices
for adjusting such mechanism, the aprons being jointed, and the regulating mechanism
being constructed and arranged substantially as herein before described.
2. The improved mechanism for distending the endless aprons of reaping machines
and comprising movable bearing bars for one roller of each apron and connected bell-
crank or other levers, for acting on the movable bearing bars, together with a spring
and external adjusting screw, the parts being arranged and operating substantially as
herein before described.
Dated this Twenty-sixth day of October 1889.
EDMUND HUNT,
Applicant's Agent.