IMPROVEMENTS IN APPARATUS FOR TRANS- MITTING AND REVERSING MOTION"
Year: 1877

page_text: LETTERS PATENT to Paul Pfleiderer of Norwood in the County of Surrey
Engineer for an Invention of "IMPROVEMENTS IN APPARATUS FOR TRANS-
MITTING AND REVERSING MOTION"
PROVISIONAL SPECIFICATION left by the said Paul Pfleiderer, at the Office
of the Commissioners of Patents on the 27th September 1877.
PAUL PFLEIDERER of Norwood in the County of Surrey Engineer
MENTS IN APPARATUS FOR TRANSMITTING AND REVERSING MOTION
"
"IMPROVE-
My invention has for its object the securing of increased compactness by dimi-
nishing the necessary total width of pulleys required by the ordinary arrangements
for transmitting and reversing motion by means of a shifting belt, also the
prevention of injury to belts due to the frequent shifting thereof, also increased
facility in reversing machinery at varying speeds, and also with reference to other
ordinary modes of reversing, the avoidance of external friction.
And a further object of my invention is to provide facilities for reversing the
action of machines automatically when a certain limit of power transmitted is
exceeded
And my invention consists in the first place in the combination of two loose
pulleys on one shaft one pulley being driven by an open strap and the other by a
crossed strap with friction or other clutches by moving which as required either
of the said two loose pulleys can be made fast and motion transmitted or reversed
with facility
The clutches consist of projections on each side of a disc secured on the shaft
between the two pulleys so as to be capable of sliding on the shaft each of
which projections can by the moving of the disc on the shaft be caused to enter
and be embraced by corresponding parts in either pulley as required.
disc can be moved on the shaft as required by means of a hand wheel and
screw and returned to its neutral position thereon by means of India rubber or
The

page_text: other springs, or the disc can be moved by other means as hereinafter described
and the pulleys liberated from the clutch by other means than springs.
In cases wherein the apparatus is fitted to the end of the driving shaft of a
machine or otherwise in an accessible position, the machine can be stopped and
reversed by hand. For stopping, the said band wheel has simply to be held fast,
while for starting it has to be turned in the direction in which the machine is to be
worked.
My invention consists in the second place in a contrivance for working the wheel
for sliding the disc on the shaft instead of as above stated by hand. This is effected
by means of a hand lever in causing a small wheel to be pressed against the periphery
of the said wheel, such small wheel being driven by another small wheel capable of
being pressed against either of two rings of different diameters on the loose pulley.
The said two small wheels are so arranged on a spindle that by pressing one always
against the wheel for sliding the disc and the other against one or other of the rims
on the pulley, the required motion in either direction is imparted to the said wheel.
And the connection between the hand lever and the two small wheels is or may be
formed by their being mounted in a bracket on the end of a rod or bar the supports
and guides of which are arranged so as to be acted upon and moved in either direction
by the lever
This contrivance of acting on the wheel in cases in which the clutches are thrown
in and out and held in position by a screw is applicable to other apparatus in
which power is transmitted by friction or other clutches whether strap pulleys or
toothed gear are used.
And my invention consists in the last place in making the apparatus to reverse the
direction of motion automatically as soon as the power to be transmitted exceeds a
certain limit which can be adjusted by a spring as hereinafter described.
In this case instead of having the friction or other clutches projecting on either
side of the sliding disc they are made separate and the disc is placed between them,
and the clutches are provided on their backs against the disc with recesses to
receive one or other of a pair of small rollers, mounted respectively on either end
of a balance lever, which is mounted on the disc and held by a spring fixed to the
disc in such a position that its ends with the rollers on thein are pressed against
one or other of the clutches. As soon as the disc is pressed towards one of the
clutches, the latter will be caused to clutch its loose pulley and give it rotation, and
the roller will pass into the recess when the motion of the clutch will be imparted
to it and through it to the balance lever and the disc on which it is mounted.
When the pressure on the roller exceeds the resisting power of the spring fixed to
the disc, the roller is forced out of the recess, whereby the balance lever is turned on
its pivot, and the corresponding roller on its other end is caused to strike against
the back of the clutch hitherto engaged, while the edge or corner by the recess tends
to wedge out the first named roller, and so the balance lever and with it the disc are
forced away from the clutch, which thereby becomes disengaged, owing to a lever
acting lengthwise on the disc having meanwhile been moved towards and thrown
over its dead point, carrying with it the disc and pressing it against the other of
the two clutches, which in its turn is now engaged.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Paul Pfleiderer in the Great Seal Patent Office on the 27th March
1878.
PAUL PFLEIDERER of Norwood in the County of Surrey Engineer "IMPROVE-
MENTS IN APPARATUS FOR TRANSMITTING AND REVERSING MOTION'
"3
"
My Invention of " Improvements in apparatus for transmitting and reversing
motion has for its object the securing of increased compactness by diminishing
the necessary total width of pulleys required by the ordinary arrangements for
transmitting and reversing motion by means of shifting belts also the prevention
of injury to belts due to the frequent shifting thereof also increased facility in
reversing machinery at varying speeds and also with reference to other ordinary
modes of reversing the avoidance of external friction.
And my Invention consists in the first place in the combination of two loose
pulleys on one shaft one pulley being driven by an open strap and the other by a
crossed strap with friction or other clutches by moving which clutches as required
either of the said two loose pulleys can be made fast and motion transmitted or
reversed with facility.
The clutches consist of projections one on each side of a disc secured on the shaft
between the two pulleys so as to be capable of sliding on the shaft each of which
projections can by the moving of the disc on the shaft be caused to enter and be
embraced by corresponding parts in either pulley as required.
The disc can be moved on the shaft as required by means of a hand wheel
and screw and returned to its neutral position thereon by means of India rubber
or other springs or the disc can be moved by other means as hereinafter described
and the pulleys liberated from the clutch by other means than springs.
In cases wherein the apparatus is fitted to the end of the driving shaft of a
machine or otherwise in an accessible position the machine can thereby be stopped
and reversed by hand. For stopping the machine the said hand wheel has simply
to be held fast while for starting the same it has to be turned in the direction in
which the machine is to be worked.
My Invention consists in the second place in a contrivance for working the wheel
for sliding the disc on the shaft instead of as above stated by hand.-This is effected
by means of a hand lever in causing a small wheel to be pressed against the peri-
phery of the said wheel such small wheel being driven by another small wheel
capable of being pressed against either of two rings of different diameters on one of
the loose pulleys.-The said two small wheels are so arranged on a spindle that by
pressing one always against the wheel for sliding the disc and the other against one
or other of the rims on the pulley the required motion in either direction is
imparted to the said wheel or to any other wheel requiring to be reversed. And
the connection between the hand lever and the two small wheels is or may be formed
by their being mounted in a bracket on the end of a rod or bar the supports and
guides of which are arranged so that it can be, acted upon and moved in either
direction by the lever.-This contrivance of acting on the wheel in cases in which
the clutches are thrown in and out of gear and held in position by a screw is
applicable to other apparatus in which power is transmitted by friction or other
clutches whether strap pulleys or toothed gear are used.
From the foregoing statement it will be clearly understood that the invention
R 10199
1
W 17870

page_text: consists essentially of two loose pulleys with an open and a crossed strap combined
with friction or other clutches which are moved into gear with either pulley
as required in order to fix it on the shaft such clutches being moved as required
either directly by hand or through the intervention of a lever and suitable
connections.
Having thus stated the nature of the said invention I will describe more par-
ticularly in what manner the same is to be performed by the aid of the accompanying
drawings in which are represented the parts of apparatus above referred to.
Fig: 1 is an elevation of an apparatus fitted with the additional contrivance for
working the hand wheel in cases in which the latter is not sufficiently accessible
or in which the speed of the machine is too great to admit of the working of the
wheel by hand.-Fig: 2 is a side view and Fig: 3 a horizontal section of the
apparatus shewn in Fig: 1 Fig: 4 shews in horizontal section the simplest
arrangement of this apparatus with a lever and sliding piston for effecting the
lateral movement of the disc from which figure may also be understood the simplest
form of the apparatus as worked by a hand wheel and screw by supposing the lever
and piston to be replaced by such hand wheel and screwed end of the disc as shewn
in Fig: 3.
Fig: 5 is a transverse section in the line A B of Fig. 4 with the pulley removed
Figures 6. 7 and
shew in partial section and plan an application of the invention
to another kind of clutches as distinguished from friction clutches.-In these second
Figures the same letters of reference indicate corresponding parts.
A is a disc capable of being moved laterally on the shaft F by means of a screwed
hand wheel H Figures 1 and 3 or a lever L and piston P (Fig 4) or other suitable
arrangement for the purpose. On the drawing the clutches c and c' are shown as
cast in one with the disc A and by moving the disc as required either the clutch o
can be put in contact with the pulley B or the clutch c¹ with the pulley B¹ by
screwing the wheel H outwards or inwards respectively while if the lever L be
used it has to be pulled either to the right or left hand in order to produce a
corresponding effect
By the use of the screwed wheel the pressure necessary to produce the clutching
or friction required for transmitting the motion of the pulley to the disc is entirely
internal thereby avoiding the wear and tear of the external friction incidental to
the use of levers or other suitable means.
In Fig: 3 I and I¹ are India rubber or steel spiral springs which serve to disen-
gage the respective pulley when the disc is withdrawn D and D¹ are washers placed
between the pulleys and are prevented by ribs r projecting from the discs A from
revolving with the pulleys E is a washer placed between the pulley B¹ and the
hand wheel H to prevent any movement of the latter by the friction of the pulley
against it GG' are collars to keep the whole apparatus in postion.
In Fig: 4 the two washers D D¹ are connected by three distance pieces K K
passing loosely through corresponding holes in the disc A. By this arrangement
the two pulleys B and B¹ are prevented from moving laterally and therefore have
no tendency to follow the disc when thrown out of contact thereby forming a
substitute for the springs I and I'
When the disc A is moved by a screwed wheel the straps or driving bands
should be put on in such a manner that the pulley nearer the screwed wheel is
caused to revolve in the direction of the hands of a watch when the apparatus is
viewed as looking towards, the hand wheel in front while the more distant pulley B
is made to revolve in an opposite direction as indicated by the arrows so that by

page_text: merely holding fast the screwed or hand wheel H the machine can at any time be
stopped while it can be started by turning that wheel in the direction in which the
machine is required to work
Instead of working the the screwed wheel by hand it may be acted upon by a
small friction wheel W Fig: 3 which is caused to revolve by the pressure of a
small roller V against one or the other of two rings R and R' fixed on the pulley B¹.—
The shaft S on which the wheels V and W are fixed is mounted in a bracket O
which can be so acted upon that the wheel W is always caused to press against
the screwed wheel H while the roller V can be caused to press either against the
rim R or R and thereby produce either of two opposite movements of the
wheels W and H.
8
8
A simple mode of acting on the bracket O in the manner referred to is repre-
sented in the drawings wherein a rod or bar s is shewn as fixed to the bracket.
The bracket and bar are supported in such a manner that one end p works in a
Blot while the rod works in two slots i and k. By moving the lever in either
direction (indicated by the arrows) a twisting of the rod s is produced which tends
to press the roller V against either the rim R or R¹ as required while at the same
time either the rod s is brought to bear against the support or the end p against the
support 9 thereby pressing the wheel W always against the screwed wheel H in
whichever direction the lever h is acted upon.-By this means a differential motion
is produced by which the wheel H can be screwed inwards or outwards at will
whether the machine is in motion in either direction or stopped thus reversing its
motion or starting it in either direction by merely acting upon a lever h in either
direction as required.
Either the inaccessibility or high speed of the pulleys forms no objection to
the application of my reversing gear when the above described contrivance is
applied.
In conclusion I would state that the advantage of the arrangement of apparatus
herein before described over the ordinary open and crossed strap reversing gear with
belt shifter is its great compactness there being only two pulleys of the single
width of the belt or strap instead of at least three two of which must be of double
width in the belt shifting apparatus.-Moreover in case the motion of the machine
in one direction should have to be quicker than that in the other my apparatus
undergoes no alteration and only the driving shafting of the factory is provided with
two fast pulleys of different diameters.
As compared with reversing by means of toothed gear the advantage of saving a
counter shaft or equivalent intermediate parts by simply crossing one of the belts
is fully gained.
And a further advantage consists in the belt being, under my Invention always
left on its pulley thereby doing away with the objectionable and injurious friction
of the belt against the fork of the belt shifter.
Having thus described the nature of the said Invention and in what manner
the same is to be performed I hereby declare that what I claim as of my
Invention is:—
First. The combination of a double friction or other clutch with two loose pulleys
one driven by an open and the other by a crossed strap or rope so as to form
an apparatus for conveniently reversing and stopping rotary motion as herein-
before described.
Secondly. The mode or method and application to such apparatus of the
contrivance herein before described for acting upon the screwed wheel H instead of
working it by hand.
And lastly, The application to reversing apparatus of the two couples of forces
produced by acting on a lever h fixed to the end of a rod s moving in slotted supports
or guides as described by which means the wheel W is pressed in one direction
against the screwed wheel H (or other wheel required to be reversed) in whichever

page_text: direction the external force which causes the pressure may be applied in order
to. produce the one or other direction of rotation of V and W with their common
shaft S.
In witness whereof I the said Paul Pfleiderer have hereunto set my hand and
seal the twenty sixth day of March in, the year of our Lord One thousand eight
hundred and seventy eight.
Witness
WILLIAM SPENCE
8, Quality Court
Chancery Lane
PAUL PFLEIDERER (L.s.)