Improvements in Speed Altering or Adjusting Mechanism for Use with Automatic Expansion or Shaft Governors.
Year: 1895

page_text: Date of Application, 26th Feb., 1895
Complete Specification Left, 26th Nov., 1895-Accepted, 28th Dec., 1895
PROVISIONAL SPECIFICATION.
Improvements in Speed Altering or Adjusting Mechanism for Use
with Automatic Expansion or Shaft Governors.
We Jonx MCLAREN and HENRY MCLAREN both of Midland Engine Works,
Hunslet, Leeds, in the County of York, Engineers do hereby declare the nature
of this invention to be as follows:-
The object of this invention is to provide simple and efficient means whereby the
tension, or compression, on the spring, or springs, of automatic expansion, or shaft,
governors can be adjusted, or varied, as required, without stopping the engine.
According to our invention the spring (or each spring), is attached at one end to
the governor weight, (or governor weights), pivotted to the engine wheel as usual,
the other end of the spring being attached to a screw carried by the said wheel,
which screw can be moved longitudinally but not rotate. On this screw a screw
nut can be rotated but it cannot move longitudinally so that, when rotated, it moves
the screw longitudinally to distend or compress, the spring to put greater, or lesser,
tension, or compression, thereon. The screw nut is rotated whilst the engine is in
motion by a friction bowl, star-wheel, or the like, mounted on an axis carried by
the wheel, which axis also carries a worm, or bevel wheel, or other suitable gear,
by which the screw out is rotated. In proximity to the said wheel is a standard,
or support, carrying a duplex device situated in the plane in which the friction
bowl, or the like, rotates, which device can be brought into contact with either side
of the friction bowl, or the like, so as to cause it to rotate, in either direction, as it
is carried in contact therewith by the rotation of the wheel and in accordance with
which side of the periphery of the friction bowl, or the like, is acted upon, the
compression, or tension, on the spring will be lessened, or increased, and the speed
of the engine altered. When a friction bowl is used it can be conveniently made
of a pair of discs with leather, or equivalent material, pinched between them, so as
to present a periphery of leather, or the like, to the duplex device with which it
comes in contact. The said dulplex device may consist of any suitable projections
to operate the friction bowl, star-wheel, or the like, such as pins in the case of a
star-wheel, or curved surfaces in the case of a friction bowl, and the said device is
so supported that it can be moved by the attendant in the standard, or support, to
one side, or the other, to press on, or engage with, the friction bowl, or the like
from one side or the other so as to rotate it in one direction, or the other, according
to whether the speed of the engine is to be increased or diminished. To maintain
the duplex device out of contact with the friction bowl, or the like, except when
the said device is operated by the attendant springs may be used to press on the
device from each side so as to normally maintain the said device in mid-position
the said springs acting preferably on pins with projections which limit the motion
of each pin to the proper place for mid-position of the duplex device so that should
either of the springs break the other will not force the device beyond the mid-
position. To prevent the said duplex device from being moved too far by the
attendant to give more than just a good contact between the friction bowl, or the
like, and the surface of the duplex device with which it comes in contact, adjusting
screws may be provided to limit the movement of the said duplex device in each
direction so that, by setting these screws, the desired amount of frictional contact
is obtained. The friction bowls, or the like, can be loaded at one side so that,

page_text: under the centrifugal force, they are prevented from turning except when in contact
with the said duplex device.
Dated this 26th day of February 1895.
JOHNSONS & WILLCOX,
47 Lincoln's Inn Fields, London, W.C., Agents.
Improvements in Speed Altering or Adjusting Mechanism for Use
with Automatic Expansion or Shaft Governors.
We, JOHN M'LAREN and HENRY MCLAREN both of Midland Engine Works
Hunslet, Leeds in the County of York, Engineers, 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 :-
The object of this invention is to provide simple and efficient means whereby the
tension or compression on the spring or springs of automatic expansion or shaft
governors can be adjusted or varied as required without stopping the engine.
According to our invention the spring (or each spring) is attached at one end to
the governor weight (or governor weights) pivotted to the engine wheel as usual
the other end of the spring being attached to a screw carried by the said wheel
which screw can be moved longitudinally but not rotate. On this screw a screw
nut can be rotated but it cannot move longitudinally so that, when rotated, it
moves the screw longitudinally to distend or compress the spring to put greater or
lesser tension or compression thereon. The screw nut is rotated whilst the engine
is in motion by a friction bowl, star-wheel or the like, mounted on an axis carried
by the wheel constituting the governor casing, which axis also carries a worm, or
bevel wheel, or other suitable gear by which the screw nut is rotated. In proximity
to the said wheel is a standard, or support, carrying a duplex device situated in the
plane in which the friction-bowl or the like, rotates which device can be brought
into contact with either side of the friction bowl, or the like so as to cause it to
rotate, in either direction as it is carried in contact therewith by the rotation of
the wheel and in accordance with which side of the periphery of the friction bowl
or the like is acted upon the compression or tension on the spring will be lessened
or increased and the speed of the engine altered. When a friction bowl is used
it can be conveniently made of a pair of discs, with leather or equivalent
material pinched between them so as to present a periphery of leather or the
like to the duplex device with which it comes in contact. The said duplex
device may consist of any suitable projections to operate the friction bowl, star-
wheel, or the like, such as pins in the case of a star-wheel, or curved surfaces-in
the case of a friction howl, and the said device is so supported that it can be
moved by the attendant, in the standard or support to one side or the other to
press on, or engage with the friction bowl or the like from one side or the
other so as to rotate it in one direction or the other according to whether the speed
of the engine is to be increased or diminished. To maintain the duplex device out
of contact with the friction bowl or the like except when the said device is operated
by the attendant, springs may be used to press on the device from each side so as
to normally maintain the said device in mid-position the said springs acting
preferably on pins with projections which limit the motion of each pin to the
proper place for mid-position of the duplex device so that should either of the
springs break the other will not force the device beyond the mid-position. To
prevent the said duplex device from being moved too far by the attendant to give
more than just a good contact between the friction bowl, or the like and the surface
of the duplex device with which it comes in contact adjusting screws may be
provided to limit the movement of the said duplex device in each direction, so that

page_text: The
by setting these screws, the desired amount of frictional contact is obtained.
friction bowls, or the like can be loaded at one side so that under the centrifugal
force, they are prevented from turning except when in contact with the said duplex
device.
In order that this invention may be well understood we will describe with
reference to the accompanying drawings the manner in which the same may be
performed. We do not however limit ourselves to the precise details hereinafter
described and illustrated.
Figure 1 is a side view and Figures 2 and 3 are sectious at right angles to each
other.
A represents a cast iron rim or casing with spokes radiating from the central
boss B which is fixed on the crank shaft of the engine.
The weights C, C, are carried by arms centered on pins D and have a tendency
to fly outwards under the action of centrifugal force when the governor revolves.
By any suitable arrangement of links and dies or other suitable gear in connection
with the weights the movement of the slide valve is controlled, the travel being
either increased or diminished, according as the weights are nearer to the rim of
the governor or to the boss.
The arc, through which the weights C move is limited by, and the force required
to send them outwards is dependent upon the resistance of the springs G. When
these springs are tightly screwed up, the speed necessary to force the weights to
their outward position near the rim of the governor is necessarily greater than
when the tension of the springs is reduced, and therefore by varying the tension of
the springs, the outward movement of the weights may be retarded, when the
engine is required to run fast, and the outward movement of the weights may be
accelerated, when the engine is required to run slow. For this purpose each
spring is secured at one end to the arm of the weight C and at the other end to
a screw H carried in a projection I on one of the arms of the governor casing.
This projection carries a nut J provided with a worm wheel around its periphery
and engaging with a worm K on a spindle M which also carries a friction wheel L
the said spindle M being mounted in a bearing on the projection I on the wheel A
and projecting to outside the governor casing. When it is desired to increase the
speed of the engine, this friction wheel L is brought into contact with a radial
shoe or rubber N having an outward surface and au inward surface-so that when
the outward surface is brought into contact with the friction wheel L it causes it
to rotate in one direction, and when the inward surface is brought into contact
with the said friction wheel L it is caused to rotate in the opposite direction. By
this means the worm K is also rotated and the nut J is caused to rotate and act
upon the screw H so as to increase or decrease the tension on the spring G and
thus increase or diminish the resistance to the outward movement of the weights,
thereby increasing or diminishing the travel of the valve upon which the speed of
the engine depends.
The radial shoe or rubber N is held in position by two spiral springs and
plungers nn so that when the shoe or rubber N is not in action both the surfaces
of the shoe or rubber N are kept clear of the friction wheel L.
The contact can be made by pulling, or, as the case may be, thrusting the
rubber or shoe N into contact with the friction wheel L; and when the desired
speed has been obtained and the rubber or shoe is released-the rubber or shoe is
forced into its neutral position-by the springs and plungers n n so that there is no
risk of damage by the rubber or shoe being left through forgetfulness or carelessness,
in a position of contact with the friction wheel L.
The springs may be in compression, instead of in tension, if preferred, the
adjustment being effected by the same means the details being altered to put
compression on, and take it off the springs, as will be readily understood without
particular description.
Instead of a friction wheel we may use a spur, star, mitre, or other gearing to
communicate the power from the shoe or rubber to the regulating screw H.

page_text: Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed, we declare that what we
claim is :-
1. In speed altering or adjusting mechanism for automatic expansion or shaft
governors the combination with the springs of means for regulating their tension
or compression substantially as hereinbefore described.
2. In speed altering or adjusting mechanism for automatic expansion or shaft
governors, coupling or connecting the springs to a screw having a nut operated by
means of a worm or other gearing, and a friction wheel or the like acted upon by
a shoe or rubber which can be moved to bring it in contact with the friction
wheel, or the like, so as to turn it in one or other direction, substantially as and
for the purpose herein before described.
3. In combination with the subject matter of the last preceding claiming clause,
an arrangement for keeping the shoe or rubber in a neutral position, when not
required in action, substantially as hereinbefore described.
4. A speed altering or adjusting mechanism consisting of the arrangement and
combination of parts herein before described and illustrated in the accompanying
drawings.
Dated this 26th day of November 1895.
JOHNSONS & WILLCOX,
47 Lincoln's Inn Fields, London, W.C., Agents.