Improved Mechanism for Producing Reciprocating Rotary Motion for Fans and the like.
Year: 1898

page_text: Date of Application, 17th Sept., 1898
Complete Specification Left. 16th June, 1899-Accepted, 22nd July, 1899
PROVISIONAL SPECIFICATION.
Improved Mechanism for Producing Reciprocating Rotary Motion for
Fans and the like.
I, THEODOR LÖHLER, of T 6, No. 36, Mannheim, Baden, Germany, do hereby
declare the nature of this invention to be as follows:-
This invention relates to improved mechanism for effecting the rotation of
a spindle, first in one direction and then in the other, for imparting a to and fro
motion to fans, punkahs and the like. I will describe the same with reference to
the accompanying drawing in which Fig. 1 shews a vertical section, Fig. a plan
and Fig. 3 a detached sectional view of part of the mechanism.
The object of the invention is to impart to the spindle 9 which may, for
example, carry at its upper end two fans, a rotary motion alternately in opposite
directions from a spindle 0 which receives a continuous rotary motion by clock
work or other means.
For this purpose there is fixed on the spindle 0 a toothed wheel 1, which
gears with two pinions 2, 2, so as to rotate them in the direction of the arrows,
Fig. 2. The spindles of these pinions are carried in the bridge shaped brackets 10
of which the one is below and the other above the plate 12 carried by pillars 11
from the framing of the driving mechanism below. The parts 3 of the spindles
is made of a square section, and upon them are fitted the bosses of heart shaped
cams 4; against the periphery of these cams bear rollers 5, 5, mounted in arms 6,
pivotted to the plate 12 and having at their free ends toothed segments that gear
with opposite sides of the pinion t.
This pinion is fixed on a spindle 7 the lower end of which has a bearing in the
plate 12 while on the upper tapered end fits a tapered socket of the spindle 9
carrying the fan blades.
The cams 4 are so arranged relatively to each other and to the arms 6 that
when for instance the right hand one in revolving from the position shewn at
Fig. 2 presses its arm 6 and toothed quadrant in the direction of the arrow, the
left hand eam at the same time recedes from its arm 6; consequently as the right
hand arm in moving as above described, will effect the rotation of the pinion t in
the direction of the arrow, this in its turn will effect the motion of the left hand
arm in the contrary direction to the right hand one, causing it to follow up its
receding cam. When the right hand cam has moved its arm 6 to the full extent
of its throw and begins to recede, the left hand cam will commence to press its
arm 6 in the contrary direction to the arrow the pinion t and its spindle 7 will
consequently also be rotated in the contrary direction to the arrow carrying with
them the spindle 9 and fans.
In order to prevent any sudden jerk on the reversal of the motion, due to the
momentum acquired by the fans, the spindle 9 is not connected rigidly to the
spindle 7 but through a coiled spring 8, which will produce a gradual starting
and stopping motion of the fans, as these can to a certain extent continue their

page_text: motion in one direction by reason of the impetus attained even after the spindle 7
has commenced to turn in the contrary direction.
The cams 4 are by preference made of ebonite to increase the softness of the
motion.
The angle through which the spindle 9 and fans are turned in either direction
will of course depend upon the proportion between the throw of the
cams, and the distance from the pivots at which they act on the arms 6,
and also the proportion between the radius of the arms 6 and the diameter of the
pinion t. These parts are generally so proportioned as to cause the fans to oscillate
through an angle between 90° and 180°.
Dated this 17th day of September 1898.
ABEL & IMRAY,
Agents for the Applicant.
Improved Mechanism for Producing Reciprocating Rotary Motion for
Fans and the like.
I, THEODOR LÖHLER, of T6, No. 36, Mannheim, Baden, Germany, do hereby
declare the nature of this invention and in what manner the same is to be per-
formed, to be particularly described and ascertained in and by the following
statement:-
This invention relates to improved mechanism for effecting the rotation of
a spindle, first in one direction and then in the other, for imparting a to and fro
motion to fans, punkahs and the like. I will describe the same with reference to
the drawing accompanying my Provisional Specification, in which Fig. 1 shews a
vertical section, Fig. 2 a plan and Fig. 3 a detached sectional view of part of the
mechanism.
The object of the invention is to impart to the spindle 9 which may, for
example, carry at its upper end two fans, a rotary motion alternately in opposite
directions from a spindle 0 which receives a continuous rotary motion by clock
work or other means.
For this purpose there is fixed on the spindle 0 a toothed wheel 1, which
gears with two pinions 2. 2, so as to rotate them in the direction of the arrows,
Fig. 2. The spindles of these pinions are carried in the bridge shaped brackets 10
of which the one is below and the other above the plate 12 carried by pillars 11
from the framing of the driving mechanism below. The parts 3 of the spindles
are made of a square section, and upon them are fitted the bosses of heart shaped
cams 4; against the periphery of these cams bear rollers 5, 5, mounted in arms 6,
pivotted to the plate 12 and having at their free ends toothed segments that gear
with opposite sides of the pinion t.
This pinion is fixed on a spindle 7 the lower end of which has a bearing in the
plate 12 while on the upper tapered end fits a tapered socket of the spindle 9
carrying the fan blades.
The cams 4 are so arranged relatively to each other and to the arms 6 that
when for instance the right hand one in revolving from the position shewn at
Fig. 2 presses its arm 6 and toothed quadrant in the direction of the arrow, the
left hand cam at the same time recedes from its arm 6; consequently as the right
hand arm in moving as above described, will effect the rotation of the pinion t in
the direction of the arrow this in its turn will effect the motion of the left has. 1
arm in the contrary direction to the right hand one, causing it to follow up its
receding cam. When the right hand cam has moved its am 6 to the full extent

page_text: of its throw and begins to recede, the left hand cam will commence to press its
arm 6 in the contrary direction to the arrow; the pinion and its spindle 7 will
consequently also be rotated in the contrary direction to the arrow carrying with
them the spindle 9 and fans.
In order to prevent any sudden jerk on the reversal of the motion due to the
momentum acquired by the fans, the spindle 9 is not connected rigidly to the
spindle but through a coiled spring 8, which will produce a gradual starting
and stopping motion of the fans as these can to a certain extent continue their
motion in one direction by reason of the impetus attained even after the spindle 7
has commenced to turn in the contrary direction.
The cams 4 are by preference made of ebonite to increase the softness of the
motion.
The angle through which the spindle 9 and fans are turned in either direction
will of course depend upon the proportion between the throw of the
cams, and the distance from the pivots at which they act on the arms G,
and also the proportion between the radius of the arms 6 and the diameter of the
pinion t. These parts are generally so proportioned as to cause the fans to oscillate
through an angle between 90° and 180°.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed, I declare that what I
claim is:-
1. Mechanism for producing the reciprocating rotary motion of a spindle carry-
ing one or more fans, consisting of two cams 4, 4, receiving continuous rotary
motion from a suitable motor and imparting a to and fro motion to two pivoted
arms 6, 6, carrying toothed segments that gear on opposite sides of a pinion t fixed
on the said spindle, the cams being so formed and arranged relatively to each other
and to the segment arms that these alternately effect the partial rotation of
the pinion and spindle in opposite directions, substantially as described with
reference to the accompanying drawing.
2. In combination with mechanism for producing reciprocating rotary motion
such as is referred to in the first claim, connecting the spindle 7 receiving
reciprocating rotary motion from the segment levers 6 to the spindle 9 carrying the
fans, by means of a coiled spring 8, for preventing jerks at the reversal of the
motion, substantially as described with reference to the drawing.
Dated this 16th day of June 1899.
ABEL & IMRAY,
Agents for the Applicant.