вход по аккаунту


Патент USA US2405382

код для вставки
» §96
original Filed Feb. 24„ 194;
Patented Aug. 6, 1946
Edouard Volet, Vevey, Switzerland
Griginal application February 24, 1943, Serial No.
476,985, now Patent No. 2,358,894, dated Sep
tomber 26, 1944. Divided and this application
June 28, 1943, Serial No. 492,620. In Switzer
land February 5, 1942
2 Claims.
This application is a division of my copending
ing axis or spindle canbe very easily performed.
A still further object of the invention is to pro
vide an improved accelerometer as aforesaid in
corporating a fluid operated relay having a piston
driven by a revolving shaft and fitted with a
pipe extension whose outlet port can effect on
application Serial No. 476,985, ñled February 24,
1943, now Patent No. 2,358,894 issued September l
26, 1944.
It is known that several types of accelerome
ters are already in existence and use particularly
for adjusting the operational speed of turbines.
Generally speaking, known accelerometers com
the one hand a relative angular motion With re
spect to the operative wall of an aperture in an
prise an inertia mass elastically secured to a shaft
inertia mass rigid with-a twistable spindle fast
so'driven by a belt or by a motor fed or energized 10
upon said shaft, said angular motion varying the
by the machine which requires to be regulated
as. to truly follow all speed variations of said
rate of ñuid delivery through said port and on
the other hand such a relative translatory mo
tion as to restore the iiuid delivery to normal
machine. Owing to this arrangement, each speed
variation of the shaft brings about a relative
value connoting balanced condition of the relay
angular displacement between the inertia mass 15 and
proper working of the machine.
elastically secured to its shaft and some suitable
part rigidly driven by said shaft. As the value of
will incidentally appear hereafter, the invention
said angular displacement is in terms- of the
comprises the novel construction and combina
acceleration, it can be used as a measure there
tion of parts that will now be described with ref
of. Moreover, in known accelerometer construc 20 erence to the accompanying diagrammatic draw
tions, the inertia mass is generally secured to its
ing which illustrates suitable embodiments of the
driving shaft by means of elastic arms. This ar
same and which forms a part of the present dis
rangement is not entirely satisfactory because a
very long and difficult job is involved in assem
In the drawing:
bling said arms and properly setting and truing 25 Figure 1 is a vertical sectional view of an ac
up their operative length and resiliency.
celerometer built for operating a hydrostatic
It is an object of the present invention to pro
vide a new or improved accelerometer pertaining
sectional viewtaken
to the aforesaid type but adapted to obviate the
foregoing disadvantages owing to the fact that 30
the inertia mass is rigidly secured to one end of
a twistable bar, spindle or axis whose other end
is rigidly driven by the shaft the speed variations
of which it is desired to measure, whereby meas
uring of the acceleration of said shaft is read
ily derived from the degree of elastic distortional
along the line II-II of Fig. 1.
Figure 3 is an isometric view partly broken
away for the sake of clearness of a more in
volved constructicnal embodiment of the ac
As will be seen from the showing of Fig. 1,
there is provided a motor l so fed or energized
from the machine which requires to bc regulated
as to truly follow all the speed variations of
twist of said bar or spindle.
Another object of the invention is to provide
this machine. One end of the motor shaft`2 or
actuator has fixed thereto a spindleV 3 con
tremely simple and yet rugged structure calling 40 stituted
by a twistable steel or like bar, thereby
_For no delicate adjustment and made up of a
permitting said spindle to undergo a high re
minimum number of parts capable of being ma
silient twist responsive to a relatively small tor
chined beforehand and readily assembled to cor
sional torque. The free end of the spindle 3 has
rect operational positions.
rigidly ñxed thereto an inertia mass Il in the form
Yet another object of the invention is to pro
of a wheel or spider extending substantially> at
vide an improved accelerometer as aforesaid in
right angle to the spindle 3.
an improved accelerometer as aforesaid of ex
corporating simple means whereby its speed droop
or statism, i. e., the relation between the speeds
of the machine in idle running condition and
in full load running condition, can be readily set
tc proper value.
A further object of the invention is to provide
an improved accelerometer as aforesaid includ
As will be readily understood, each speed vari
ation of the driving shaft 2 produces, owing to
the inertia mass which must be driven thereby,
a torque the tendency of which is to twist the
spindle or bar 3. Such torque exerts a torsional
stress upon said spindle. The_value of said tor
sional stress or twist is in terms of the accelera
l ing simple means whereby centering and balanc
ing of the inertia mass with respect to its carry
tion. As a result of this, the mass 4 is angularly
displaced with respect to the actuating shaft _2.
4This displacement is a measure of the accelera
In the constructional form of the accelerome
ter shown in the drawing, the angular displace
ments of the inertia mass 4 hydrostatically oper
ate a differential relay 5 by throttling or open
tudinal slots 23 extending parallel to the rota
tional axis and with a slot 24 extending obliquely
to said axis. Moreover, the sleeve unit thus
formed has rigidly ñxed thereto a plate'4 I8 into
which is fitted one end of a spindle I9.,? This
spindle is aligned with the shaft 2 and has its
other end provided with an intermediate member
ing out more or less (as the case may be) an
26 fixed in turn to a yoke member 2l engaged
outlet port E formed in a member connected to,
through the slots 23 and rigidly connected to the
and non-distortably driven by, the actuating
inertia mass 4 which is cylindrical and freely en
shaft 2 through the medium of a toothed wheel 'l 10 compasses the sleeve unit. The cam slot 24 forms
which is fast upon said shaft and which in turn
a guide for a block 25 rigid on the pipe 8 formed
drives a bar I5 integral with a hollow rod or
at its free end with the outlet port 6. The pipe
pipe 8 of cranked outline whose upper end termi
S is engaged through an elongated aperture 26
nates in the port 6. The latter is arranged in
formed in the mass 4 parallel to the rotational
front of a radially extending slanting wall 9 de
axis. The port 6 is formed at the end of the
fining an aperture in the mass il as shown in
pipe B in front of the operative face 21 of the
Fig. 2.
aperture 26. The pipe 8 is connected at its end
The relay comprises a cylinder in which is slid
remote from the port 6 to a differential hydro
ably and revolubly housed a piston l0 defining a
static relay similar to the one described with
pair of chambers l l, l2 of varying volumes inter 20 reference to Fig. l.
connected by an accurately gagedl narrow chan
The spindle i8 is capable of being twisted,
nel i3 and receiving fluid from an inlet pipe i4.
wherefor it has a small diameter and is made of
The upper chamber l2 communicates through
a material having a high mechanical strength to
port 8a with the pipe 8 which, as above stated,
gether with a high degree of resiliency so that
terminates in the port 6.
when the shaft 2 undergoes a change of speed,
As will be observed, any angular displacement
the inertia of the mass ¿l brings about a resilient
of the inertia mass 4 moves the radially extend
torsion of the spindle i9 and therefore a rela
ing wall 9 olf or toward the port 6, thereby alter
tive angular displacement of said mass 4 with re
ing the intensity of fluid delivery therethrough.
spect to the sleeve Il. This unmasks the port 5
Such alteration breaks the equilibrium' between
and alters the rate of huid flow therethrough,
those thrusts exerted on both faces of the piston
thus varying the fluid pressure inside the pipe ß.
which is therefore axially shifted. As a result
Such angular displacement is a linear function
of this, the port B effects’ a translatory motion
of the acceleration.
since the bar l5 has a slidingr ñt in a sleeve |62
As described with reference to Fig. l, a varia
formed integral with the wheel l. As the radially " tion in the rate of fluid flow through the port 6
extending wall 9 slants with respect to the >rota
breaks the balance between the thrusts exerted
tional axis of the inertia mass 4, such a dis
on both faces of the piston i9. Consequently the
placement of the port 6 along the slanting wall
- latter is shifted and moves with it the pipe 8.
9 tends to correct the alteration of iiuid flow
In the construction shown in Fig. 3, the orien
intensity caused by the angular displacement of 40 tation of the Obliquity of the guiding or camming
the mass 4. Consequently the piston lil re
slotI 2f! is so provided as to cause the longitudinal
displacement of the piston lû to bring about a
trieves a balanced position as soon as the inten
restoration of the original rate of delivery through
sity of fluid delivery through the port 6 has re
the port 'ô by shifting the angular position of said
sumed its original value.
As will be seen, it is the inclination of the ra 45 port with respect to the wall 2l. Consequently
the Obliquity of the camming slot 24 determines
dially extending wall 9 which provides for proper
the speed droop of the accelerometer or in other
speed droop of the accelerometer or in other words
words the ratio between the speed of the machine
for the relation between the speed of the ma
when it runs idle and its speed when it runs un
chine When it runs idle and its speed when it runs
under full load. In order to modify the' value 50 der full load. It is evidently possible, with a view
to allowing of a variation of said speed droop,
of said speed droop, it would be suiiicient for ex
to provide a guiding slot 24 ’having adjustable
ample to provide for said wall to be orientatable
under the control of a movable member ñxedly
obliduity or camming action.
It will be seen that the aforesaid accelerometer
secured to the mass 4 by means of any known or
conventional device enabling the degree of slant 55 has an extremely simple construction and calls
for no precise adjustment inasmuch as all the
of said wall V9 to be altered with respect to the
parts of which it is made up can be built and ma
rotational axis of the mass 4. Owing to such an
chined beforehand and then assembled together
arrangement, it would become possible to also
>without requiring any special manipulation or
modify the speed droop of the accelerometer by
varying in any conventional way the useful length 60 skilled labor. As the inertia mass 4 is rigidly
iixed to its carrying spindle, proper centering and
of the spindle or in other words the distance
balancing thereof present no diilìculty whatever.
between the point at which it is fitted to the shaft
Obviously the angular displacement of the mass
2 and the point at which the mass 4 is secured.
4 with respect to the driving shaft 2 may be meas
Alternatively the speed droop of the accelerometer
might be varied by imparting-by means of a 65 ured by means of a device other than the one de
scribed in the foregoing. Such displacement may
conventional device, an adjustable inclination to
be measured for example optically by means of a
the bar l5 with respect to the rotational axis of
pair of disks formed with slots, one of said disks
the mass 4 and also by arranging for the wall 9
being integral with the mass 4. while the other
to extend in a plane passing through said rota
disk is integral with or secured to the shaft 2.
tional axis.
such displacement may be meas
The constructional embodiment of the accel
ured electrically by varying the coupling condi
erometer shown in Fig. 3 comprises a sleeve I1
tions between a pair of coils or windings, one of
rigidly secured to the shaft 2 which revolves as
which is supported by the mass 4 while the other
shown by the arrow. The sleeve I1 has a cylin
drical extension 22 formed withv a pair of longi 75 one is driven by the shaft 2.
Minor constructional details might be changed
2. An accelerometer for maintaining constant
speed of an operating machine, comprising, in
without sacrificing the aforesaid advantages or
departing from the scope of the sub-joined claims.
combination, a driven shaft, a rotatable member
What is claimed is:
to said shaft to rotate therewith, said mem
l. An accelerometer for maintaining constant Ul ber having
guide means extending parallel to the
speed of an operating machine, comprising, in
axis of rotation of the said member and also hav
combination, a driven shaft, a sleeve ñxed to
ing a cam surface extending obliquely to said
said shaft to rotate therewith, said sleeve having
an annular inertia mass arranged co-axially
a pair of longitudinal slots extending parallel to
with the shaft and having an aperture; a twist
the axis of rotation of the sleeve and also hav 10 able resilient spindle arranged co-axially with
ing a cam slot extending obliquely to said axis,
the shaft, rotatable member, and annular iner
an annular inertia mass arranged co-axially with
the shaft and having an aperture; a twistable re
silient spindle arranged co-axially with the shaft,
sleeve, and annular inertia mass; means for con
necting one end of the spindle rigidly to the sleeve,
a yoke member rigidly connected to the other end
of the spindle and having its outer end portions
engaged in said longitudinal slots of the sleeve,
tia mass; means for connecting one end of the
spindle rigidly to the rotatable member, a yoke
member rigidly connected to the other end of
15 the spindle and having its outer end portions
engaged with said guide means and cam surface,
and means to transform the angular movement
of the inertia mass into an axial movement for
modifying the speed of rotation of said shaft
and twist responsive means for modifying the 20 through the relative differential movement be
speed of rotation of said shaft through the rel
tween the inertia member and the rotatable mem
ative differential movement between the inertia
ber, said means including a fluid cylinder dis
member and the sleeve, said means including a
posed co-axially with the shaft and spindle,
iluid cylinder disposed co-axially with the shaft
a ported piston in said cylinder dividing the
and spindle, a ported piston in said cylinder divid 25 same into opposite chambers, a cranked hollow
ing the same into opposite chambers, a cranked
pipe element connected at one end with the pis
hollow pipe element connected at one end with
ton and communicating with one of the chambers
the piston and communicating with one of the
of the ñuid cylinder and, having its other end
chambers of the ñuid cylinder and having its
terminating in a port disposed in said aperture
other end terminating in a port disposed in said 30 of the inertia member, and means carried by the
aperture of the inertia member, and means car
pipe element and slidable on the cam surface of
ried by the pipe element and slidable in the cam
the rotatable member whereby relative movement
slot of the sleeve whereby relative movement be
between the rotatable member and inertia mass
tween the sleeve and inertia mass will move the
will move the port of the pipe element into and
port of the pipe element into and out of engage 35 out of engagement with a wall'of the said aperture
ment with a wall of the said aperture in the
in the annular member.
annular member.
Без категории
Размер файла
497 Кб
Пожаловаться на содержимое документа