Improvements in Governors for Steam Engines and other Motors.
Year: 1894

page_text: Date of Application, 18th Sent., 1894-Accepted, 14th Sept., 1895
COMPLETE SPECIFICATION.
Improvements in Governors for Steam Engines and other Motors.
I, JOSIAH Dow, of No. 5119 Pulaski Avenue, German Town in the City of
Philadelphia, Pennsylvania, United States of America, 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:-
This invention relates to governors for steam engines and other motors, as I shall
describe referring to the accompanying drawings.
Figs. 1 and 2 are vertical sections, on planes at right angles to each other, of a
governor according to this invention."
Fig. 3 is a plan of the top.
Fig. 4 is a plan on the line 4-4, of Fig. 1.
Figs. 5 and 6 are vertical sections, on planes at right angles to each other,
illustrating a modification in the compensation mechanism.
Fig. 7 is a plan on the line 7-7 of Fig. 5.
A frame consisting of base 1, bracket and arms 2 and 3 and top plate 4 carries
the arnular base 5 of an upper open frame having curved arms 6 supporting a
horizontal internally toothed ring 7 on which is fixed a frame 8 with radial arms 9
supporting a shaft bearing 10. In this bearing 10 is journalled the upper end of
the vertical governor shaft 11 the lower end of which is stepped in a bearing 12 on
the base plate 1.
On the shaft 11 is keyed a pinion 13 gearing with a wheel 14 on a shaft 15
connected with the engine shaft by any suitable gear.
On an enlarged portion 16 of the governor shaft 11 a boss 17 is fitted to slide
vertically with a feather or key so as to revolve with the shaft. From this boss 17
project upwards and outwards two opposite arms 18 carrying planet wheels 19 that
gear with the toothed ring 7. Each planet wheel 19 has attached to it a pinion 20
gearing with a spur wheel 21 having on its underside an elongated boss 22 which
is free to revolve on the governor shaft, and carries at its lower end a bevil
wheel 23 gearing with two bevil wheels 24 which are mounted free to revolve on
opposite arms 25, projecting radially from the boss 17. Each of the bevil wheels 24
has an outwardly prolonged boss 26, extending to a collar 27 fixed on the arm 25
so as to hold the wheels 23 and 24 in gear.
On the elongated bosses 26 are fitted with feathers friction wheels 28 that
revolve with the bevil wheels 24 but can slide along the bosses 26 outwards under
the influence of centrifugal force, or inwards under the action of springs.
Cylindrical caps 29 are fitted to slide on the arms 25 their ends bearing against
the bosses of the friction wheels 28. These caps 29 have on opposite sides
longitudinal slots 30 in which are engaged pins 31 fixed in the arms 25 these pins
preventing the caps from turning and from sliding beyond a certain distance.
As shewn in Fig. 2, the arms 25 are tubular containing helical springs 32 to
draw in the friction wheels 28 in opposition to the centrifugal force. The inner
ends of the springs 32 are attached to the boss 17 by pins 33 and their outer ends
are attached to bolts 34 that pass through the heads of the caps 29 and are secured
therein by nuts 35 and jam-nuts 36. The pins 33 may be arranged so as to assist
in fastening the arms 25 to the boss 17.

page_text: The friction wheels 28 bear on a disc 37 mounted on the plate 4 preferably on
ball bearings 38. The upper face of the disc 37 may be roughened to increase the
friction hold' of the wheels 28. Each of these wheels 28 may have in its periphery
a ring 39 of indurated fibre, hide, caoutchouc or other suitable material, to increase
friction and reduce noise.
As the boss 17 has free longitudinal movement on the shaft enlargement 16, the
weight of the boss and gearing carried by it assists the frictional hold of the
wheels 28 on the disc 37.
On its underside the disc 37 has a boss 40 carrying a pinion 41 beneath a boss 42
on the plate 4 which gears with the teeth 43 of a rack 44 connected to a slide or
other cut off valve, which is not shewa. The rack 44 is moved in the one direction
or the other according as the disc 37 is made to revolve in the one direction or the
other by the action of the friction wheels 28. The teeth of the rack are extended
along the same only so far that the full opening or closing of the valve is effected
as the last tooth at either end of the rack is released from the pinion 41, then a
spring 45 pressing against a pin 46 on the rack bar holds the last tooth against the
pinion 41, in readiness for the return movement of the rack. Thus, the disc 37
may continue to revolve even when the valve is entirely closed or opened without
moving the rack bar until the reverse movement takes place to which the rack at
once responds.
The proportions of the gearing in the differential mechanism of the governor
should be such that each of the friction wheels 28 turns once on its own axis while
it revolves once around the axis 11 of the governor. If therefore these friction
wheels 28 normally bear upon the disc 37 at a distance from the axis of the
shaft 11 equal to their own radius they have merely rolling contact with the disc,
and the line in which they thus travel may be termed the "neutral" or "normal
line" of contact. When however, the speed of the governor becomes such that
the centrifugal force moves the wheels 28 outwards until they travel in a circle
beyond the neutral or normal line, they then impart movement to the disc 37 in
such direction that the rack bar 44 thus moved effects a diminution or cut off of the
supply of steam or other working fluid.
On the other hand, when the speed decreases the centrifugal force is corre-
spondingly diminished and the springs 32 draw the friction wheels 28 inwards
within the neutral point or line, causing the disc 37 to revolve in the opposite
direction, moving the rack 44 so as to increase the supply of working fluid.
In order to give the governor delicacy and efficiency of action, the gearing of
the planetary-train should have the following proportions the wheels 23 and 24
being equal or mitre. The ring 7 has a pitch diameter three times that of the
planet wheels 19 and twice that of the central wheel 21, the planet wheels 19 have
a. pitch diameter twice that of their pinions 20, and the central wheel 21 has a
pitch diameter three times that of these pinions.
The springs 32 may have their tension adjusted by the nuts 35 and 36 so as to
equalise the action of the two wheels 28 and determine the normal speed.
As additional means of controlling. the friction wheels 28 so as to secure
uniformity of their longitudinal movement along their axes, the caps 29, as shewn
in Fig. 7, may have jointed to them curved links 47, connecting them to levers 48
pivotted in the boss 17, and, instead of employing the springs 32 shewn in Fig. 2,
the arms 25 may be solid as shewn in Fig. 6, and outside springs 49 as shewn in
Figs. 5 and 7 may have their ends connected to or bearing on lugs 50 carried by
projections from opposite levers of each pair of the levers 48, so as to exert an
inward drag on the caps 29.
In addition to the springs, a weight pot 51, Figs. 1 and 2 which can be loaded
as desired may be fitted to slide on, and revolve with the shaft 11, this "weight
pot" having an elongated tubular boss 52 with clamps and screw bolts 58, 59
suspended by wires or cords 53 which pass over pulleys 55 situated in a chamber 54
aud through openings 56 and 57 in the enlargement 16 and are secured to the
bolts 34 in the heads of the caps 29.

page_text: The pin 60, carrying the pulleys 55, may be supported in the shaft 11, so that
the weight pot does not load the disc 37, or it may be extended through a slot and
fixed in the boss 17 so as to increase the frictional load on the disc 37.
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. In a governor for steam engines and other motors, wherein a pair of friction
wheels, rotated by suitable gear, are caused by centrifugal force, acting in
opposition to adjusted or loaded springs, to slide more or less along horizontal
revolving arms, so that their peripheries, bearing on the face of a disc at a greater
or less distance from its axis, by friction cause this disc to revolve in the one or the
other direction, and to move, by means of a pinion and rack or equivalent
connection a slide or other cut off valve, the gear for driving the friction wheels,
consisting of the internally toothed ring 7, the planet wheels 19 and their
pinions 20, the wheels 21 with which the pinions gear, and the bevil gear 23 and 24,
substantially as described.
2. The modified arrangement of springs wherein the arms 25 are solid and
external springs 49 are applied to levers 48 linked to the caps 29, substantially as
described with reference to Figs. 5, 6, and 7.
3. In combination with the hollow arms 25, sliding caps 29, and springs 32, the
weight pot 51 wires or cords 53 and pulleys 55, substantially as and for the purpose
set forth.
Dated this 18th day of Santamber 1901.
ABEL & IMRAY,
Agents for the Applicant.