An Improvement in Hay and Straw Elevators.
Year: 1891

page_text: Date of Application, 13th May, 1891
Complete Specification Left, 4th June, 1891-Accepted, 18th July, 1891
PROVISIONAL SPECIFICATION.
An Improvement in Hay and Straw Elevators.
I, HENRY ROBERTS of Stony Stratford, in the County of Bucks, Engineer and
Ironfounder, do hereby declare the nature of this invention to be as follows:-
This invention relates to a further improvement in hay and straw elevators of the
kind for which previous Letters Patent were granted dated the 7th day of May
1884, No. 7366; and it has for its object to provide an additional means of operating
the stop mechanism for the prevention of overwinding of the gear by which the
elevator is folded and unfolded and raised into position for working.
In such former Specification, the locking pawl, by which the rotation, in either
direction, of the first motion shaft was prevented, engaged with one or other of
oppositely directed lugs, and was brought into operation at the proper moment by
lugs on the wheel (designated the pole wheel) to which the pole or strut of the
elevator trough was fixed.
These lugs were operative only in two positions of the elevator trough, namely in
its folded position and in its lowermost extended position, that is to say in the two
extreme positions of the pole or strut at the opposite ends of the arc described
thereby, but there is a third intermediate position in which the prevention of
overwinding is necessary, to avoid breakage, namely when the trough is extended
and elevated to its highest position.
This position being intermediate of the other two, it is necessary to provide a
means of operating the stop mechanism which will only come into operation when
the elevator trough is extended and so allow of the pole or strut passing this
position freely in the operation of folding the trough.
To this end, I provide upon the said pole wheel a third lug intermediate of the
other two in such position that it can only act on the locking pawl through the
medium of a part which, when the lower section of the elevator trough is lowered,
is retracted by the weight of the said section acting upon it through suitable
connections, so that it is withdrawn from the path of the said lug, and which, when
the section of the elevator is raised, is brought into operative position by the action
of a spring.
Dated this 13th day of May 1891.
COMPLETE SPECIFICATION.
An Improvement in Hay and Straw Elevators.
I, HENRY ROBERTS, of Stony Stratford, in the County of Bucks, Engineer and
Ironfounder, 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 relates to a further improvement in hay and straw elevators of the
kind for which previous Letters Patent were granted dated the 7th day of
May 1884, No. 7366 which had for its object to provide means of operating the
stop mechanism for the prevention of overwinding of the gear by which the elevator
is folded and unfolded and raised into position for working.
This stop mechanism was operative only in two positions of the elevator trough,
namely in its folded position and in its lowermost extended position, that is to say
DQ11

page_text: .
in the two extreme positions of the elevator supporting pole or strut at the opposite
ends of the are described thereby, but there is a third intermediate position in
which the prevention of overwinding is necessary, to avoid breakage, namely when
the trough is extended and elevated to its highest position. This position being
intermediate of the other two positions, any means, provided for operating the stop
mechanism for preventing overwinding at this particular position, must only come
into operation when the elevator trough is extended in order that the pole or strut
may pass this position freely in the operation of folding the trough; and it is the
object of this present invention to provide such additional means of preventing
overwinding which will come automatically into operation only at the proper
moment.
Reference is to be had to the accompanying drawings, forming part of this
Specification, wherein Figure 1 is a part sectional side elevation of sufficient of the
elevator winding mechanism, to illustrate my present improvement, and Figure 2 is
a section of the same through the axis of the locking wheel on the first motion or
worm shaft. The same letters of reference denote like parts in both figures.
A is the first motion or worm shaft, B the locking wheel keyed thereon having
oppositely directed lugs with one or other of which engages the locking pawl &
when the pole or strut reaches one or other end of its course, the pawl being at
other times held in the intermediate position shewn, by a spring c. D is the
supporting pole or strut of the elevator trough, E the pole wheel to which the heel
of the pole is fixed, said wheel being internally toothed and driven by the train of
worm and toothed gear F, G, H, I, from the worm on the first motion shaft, said
wheel E having two lugs e el on its periphery in position to act on the tail end c of
the pawl C and to throw it into engagement with one or other of the lugs bb, on
the pole or strut D reaching one or other end of its course, all as before described
in the Specification of the former Patent aforesaid.
For the purpose of operating the said stop mechanism from a point of the wheel E
intermediate of the lugs e el only when the extended trough is raised to its highest
position, provide upon the said pole wheel E a third lug intermediate of the
other two and on the inner face of the wheel rim, so that it will not act directly on
the locking pawl C but only through the medium of an arm J which, when the
lower section of the elevator trough is raised, is brought into operative position, as
represented in the drawing, by the action of a spring K so as to be struck by lugj
and serve as the medium by which the latter acts on the locking pawl and throws it
into engagement with the lug b. When, however, the said lower section of the
elevator trough is lowered (as indicated at L by dotted lines in Figure 1) so as to
rest on its seat on the framing, its weight, acting through suitable' connections,
overcomes spring K and causes the arm to be withdrawn out of the path of the
lugj so that said hig becomes inoperative. For this purpose, the arm is pivoted
to one inember of an elbow lever M. pivoted to the main frame, an upright thrust
rod m being attached to the other member and sliding through a guide hole in the
part of the frame on which the section L of the elevator rests when lowered so as to
be pressed upon thereby. The spring K is a spiral spring about a thrust rod k pivoted
to the arin J and sliding in a guide bearing fixed on the frame between which
and an abutment on the rod k, the spring is confined, so that when the weight of the
lowered section comes on the rod m, the end of the arm I will be retracted wholly
within the path of the lug j.
It will be obvious that the action of a weight might be substituted for the
spring K and that the arm J and the mechanism whereby it is put out of operative
position, might be variously modified without departing from the invention.
Having now particularly described and ascertained the nature of the said 'inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
:-
1. In stop winding mechanism for hay and straw elevators,' the combination,
with the stop winding or locking pawl adapted to engage with the first motion'shaft

page_text: and with the pole wheel, of means adapted to be thrown by a spring into position to
act on the pawl and to be withdrawn from operative position by the weight of
the lower section of the elevator acting on it through suitable connections, as
described.
2. In stop winding mechanism for hay and straw elevators, the combination, with
the stop winding or locking pawl adapted to engage with the first motion shaft and
with the pole wheel, of the lug on the face of said wheel and of the arm held by a
spring in position to act as the medium between the said lug and pawl and adapted
to be withdrawn from operative position by the weight of the lower section of the
elevator acting on it through a thrust rod and elbow lever, substantially as
specified.
Dated this 4th 1.
H. ROBERTS.
By A. M. & Wm. Clark,
53, Chancery Lane, London, Patent Agents.