U.S. patent number 3,818,284 [Application Number 05/312,830] was granted by the patent office on 1974-06-18 for valve control with pulse width modulation.
This patent grant is currently assigned to Marotta Scientific Controls, Inc.. Invention is credited to William I. deVersterre, Donald A. Worden.
United States Patent |
3,818,284 |
deVersterre , et
al. |
June 18, 1974 |
VALVE CONTROL WITH PULSE WIDTH MODULATION
Abstract
This control, intended primarily for valve actuation, provides
signals with pulse width modulation. The frequency of the pulse is
high enough to produce dither in the controlled valve or other
mechanical element; this being an effective way of making the
operation of a mechanical element more delicate by reducing or
eliminating static friction. The pulses are obtained by a
mechanical shield that intercepts a supply of radiant energy and
the width of the pulse is controlled by moving a non-circular
shield further into or out of the path of the radiant energy.
Rotating plates are used as the shield; and the path of radiant
energy is from a source on one side of the plate to a receiver on
the other side of the plate; the source and receiver being carried
by the same bifurcated lever.
Inventors: |
deVersterre; William I.
(Warren, NJ), Worden; Donald A. (Pompton Plains, NJ) |
Assignee: |
Marotta Scientific Controls,
Inc. (Boonton, NJ)
|
Family
ID: |
23213203 |
Appl.
No.: |
05/312,830 |
Filed: |
December 7, 1972 |
Current U.S.
Class: |
361/142; 250/233;
361/176 |
Current CPC
Class: |
G08C
23/06 (20130101) |
Current International
Class: |
G08C
23/06 (20060101); G08C 23/00 (20060101); H01h
047/24 () |
Field of
Search: |
;317/124
;250/231,233,234 ;84/1.18 ;330/59 ;324/97 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Miller; J. D.
Assistant Examiner: Moose, Jr.; Harry E.
Attorney, Agent or Firm: Sandoe, Hopgood & Calimafde
Claims
What is claimed is:
1. Control apparatus for supplying different amounts of electrical
energy through a circuit in accordance with the displacement of a
control element, including in combination a source of radiant
energy that directs an energy beam along a path, a
radiation-responsive receiver in a control circuit and in position
to receive radiant energy from said source and to control the power
in the circuit in proportion to the radiant energy received, said
receiver being in a fixed position with respect to the path of the
beam, a radiant energy shield between the source and the receiver,
said shield having a peripheral edge that is of different radius at
angularly spaced locations along said peripheral edge and that is
movable into and out of the path of the beam, and motor means
connected with the shield for moving the shield through a cycle,
the control element being movable for changing the relative
positions of the shield and the path of radiant energy to change
the portion of each cycle during which the shield moves into the
path of the beam to shut off radiant energy supplied along said
path from the source to said receiver.
2. The control apparatus described in claim 1 characterized by the
shield being a plate that rotates about an axis, a portion of the
plate intersecting the path of the radiant energy during the cycle
of movement of the plate.
3. The control apparatus described in claim 2 characterized by the
adjustment device being movable into different positions to shift
the path of radiant energy and the axis of rotation of the plate
closer to and further from one another to change the percentage of
the cycle during which the plate shields the receiver from the
radiant energy from said source.
4. The control apparatus described in claim 2 characterized by a
housing in which the plate, sources and receivers are enclosed, the
controller being a lever with a portion enclosed in the housing and
to which the source and receiver are connected, said lever
extending through a wall of the housing, a handle portion of the
lever outside of the housing, the housing being of modular
construction, and a similar modular housing enclosing similar
structure, and a lever extending through a wall of the similar
housing, means connecting the housings together into a control
apparatus assembly with the axes of rotation of the plates in
substantial alignment with one another.
5. The control apparatus described in claim 4 characterized by a
plurality of housings, similar plates, sources and receivers in the
different housings, means connecting the housings together with the
axes of rotation of the plates in alignment and axles of the plates
operatively connected together, a single motor at one end of the
connected housings for driving all of the plates, a lever extending
through the wall of each of the housings, with handles in similar
positions on the levers at the different housings, conductors
connected with the different sources and receivers, and a common
cable leading from one end of the housing assembly and containing
extended portions of said conductors.
6. The control apparatus described in claim 2 characterized by the
plate having angularly spaced depressions at its peripheral edge
correlated with the positions of the source and receiver to permit
passage of at least a portion of the radiant energy from the source
to the receiver when the apparatus is adjusted for maximum
shielding of the path of radiant energy.
7. The control apparatus described in claim 1 characterized by
there being a second source of radiant energy and a second
radiation-responsive receiver in position to receive energy from
said second source, the radiant energy shield being in position to
shield both of the receivers from their sources of energy, the
control element being connected with both of the receivers and both
of the sources of energy and movable into different positions to
selectively alter the percent of each cycle during which each path
of radiant energy is obstructed by the shield.
8. The control apparatus described in claim 7 characterized by the
control element having a mid position in which the shield has
maximum shielding effect on both the paths of radiant energy, and
the control element being connected with the receivers and sources
so as to decrease the effect of the shield on one path of radiant
energy when moved in one direction and on the other path of radiant
energy when moved in the opposite direction.
9. The control apparatus described in claim 1 characterized by a
frame that supports the source, receiver and shield, the control
element including a handle portion extending from the frame, a
connector portion extending longitudinally through a part of the
frame, and bearing means in which the control element rocks about
an axis transverse of the direction of longitudinal extent of the
connector portion.
10. The control apparatus described in claim 11 characterized by a
frame that supports the source, receiver and shield, the control
element including a handle portion extending from the frame, other
bearing means about which the handle portion of the control element
rocks about another axis at an angle to the direction of extent of
the first axis to give the controller universal rocking movement
transverse of the direction of longitudinal extent of said
connector portion.
11. The control apparatus described in claim 10 characterized by
there being a plurality of source and receiver assemblies supported
by the frame for controlling different circuits, connections
between the connector portion and one source and receiver assembly
for controlling only the influence of the shield on that source and
receiver assembly when the handle rocks about one axis only, and
connections between the connector portion and another source and
receiver assembly for controlling only the influence of the shield
on said other source and receiver assembly when the handle rocks
about the other axis only, both of the source and receiver
assemblies being influenced when the handle rocks about both axes
simultaneously.
12. The control apparatus described in claim 11 characterized by
bearing means in which the handle portion of the control element is
also rotatable about its longitudinal axis in addition to its
rocking movement, a third source and receiver assembly supported by
the frame, a crank operatively connected with the handle portion
and that moves angularly about the longitudinal axis of the handle
portion when said handle portion is rotated about its axis, and a
link connecting the crank with the third source and receiver
assembly for moving the third source and receiver assembly in
response to said rotation of the handle portion, the link being
connected with the handle portion so as to avoid transmitting
motion of the rocking movement of the handle portion to the third
source and receiver assembly.
13. The control apparatus described in claim 12 characterized by a
plate constituting the shield for all of the receiver and source
assemblies, each of the receiver and source assemblies including a
bifurcated lever extending on both sides of the plate, the levers
being located at angularly spaced locations around the periphery of
the plate, each of the levers having a bearing on which it has
oscillating movement to both sides of a neutral center position,
springs holding each of the levers in its neutral position, an
operating crank extending from a first of said levers and having a
slit extending in the direction of movement of one end of the
handle portion when the handle portion rocks about one of its axes
of rocking movement, another operating crank extending from a
second of said levers and having a slit extending in the direction
of movement of one end of the handle portion when the handle
portion rocks about the other of its axes of rocking movement, an
operating crank extending from a third of said levers, the third of
said levers being connected by said link to the crank which is
operated by rotation of the handle portion but not by the rocking
movement of the handle portion about either of its transversely
extending axes that impart the universal rocking movement to the
handle portion.
14. The control apparatus described in claim 1 characterized by a
frame that supports the source, receiver and shield, a digital
element including a handle portion extending from the frame, the
handle portion being rotatable about its longitudinal axis, a crank
arm extending from one side of the handle portion, means connecting
the crank arm and the handle portion for angular movement of the
crank arm when the handle portion is rotated, said connections
preventing angular movement of the crank during rocking movement of
the handle portion, and a motion-transmitting link between the
crank and the portion of the control element that extends nearest
to the shield.
15. Control apparatus for supplying different amounts of electrical
energy through a circuit in accordance with the displacement of a
control element, including in combination a source of radiant
energy, a radiation-responsive receiver in a control circuit and in
position to receive radiant energy from said source and to control
the power in the circuit in proportion to the radiant energy
received, a radiant energy shield between the source and the
receiver, said shield having a peripheral edge that is of different
radius at angularly spaced locations along said peripheral edge,
and motor means connected with the shield for moving the shield
through a cycle, the control element being movable for changing the
relative position of the shield and the path of radiant energy with
respect to one another to change the portion of each cycle during
which energy is supplied from the source to said receiver,
characterized by the control element including a movable carrier,
the source of radiant energy and the receiver being located
adjacent to the movable carrier and one of them being connected to
and movable as a unit with the movable carrier.
16. The control apparatus described in claim 15 characterized by
the movable carrier being a bifurcated lever with the bifurcated
portions thereof extending on different sides of the plane of
movement of the shield, and the receiver and the source of radiant
energy being carried by the lever and on the bifurcated portions
thereof so that said receiver and source of energy are on opposite
sides of the shield.
17. Control apparatus for supplying different amounts of electrical
energy through a circuit in accordance with the displacement of a
control element, including in combination a source of radiant
energy, a radiation-responsive receiver in a control circuit and in
position to receive radiant energy from said source and to control
the power in the circuit in proportion to the radiant energy
received, a radiant energy shield between the source and the
receiver, said shield having a peripheral edge that is of different
radius at angularly spaced locations along said peripheral edge,
and motor means connected with the shield for moving the shield
through the cycle, the control element being movable for changing
the relative position of the shield and the path of radiant energy
with respect to one another to change the portion of each cycle
during which energy is supplied from the source to said receiver,
characterized by the shield being a plate that rotates about an
axis, a portion of the plate intersecting the path of the radiant
energy during the cycle of movement of the plate, and further
characterized by the control element extending on both sides of the
plate, the receiver and the source of energy being carried by said
control element and located on opposite sides of the plate from one
another, the control element being movable to shift the receiver
and source of energy toward and from the axis of rotation of the
plate to change the percent of time that the path of radiant energy
is obstructed by the peripheral portion of the plate during each
cycle of rotation of the plate about its axis.
18. The control apparatus described in claim 17 characterized by
the control element being a lever that swings angularly about an
axis substantially parallel to the axis of rotation of the plate to
locate the receiver and source of energy in position to have the
radiant energy pass between them intersected by peripheral portions
of the plate for greater or lesser portions of each cycle of
rotation of the plate as the receiver and source of energy are
moved closer to and further from, respectively, the axis of
rotation.
19. The control apparatus described in claim 18 characterized by
there being two sources of radiant energy, and a separate receiver
for each source of radiant energy, the different receivers and
sources being at different locations angularly around the periphery
of the plate, and both of the receivers and sources being movable
toward and from the axis of rotation of the plate.
20. Control apparatus for supplying different amounts of electrical
energy through a circuit in accordance with the displacement of a
control element, including in combination a source of radiant
energy, a radiation-responsive receiver in a control circuit and in
position to receive radiant energy from said source and to control
the power in the circuit in proportion to the radiant energy
received, a radiant energy shield between the source and the
receiver, said shield having a peripheral edge that is of different
radius at angularly spaced locations along said peripheral edge,
and motor means connected with the shield for moving the shield
through a cycle, the control element being movable for changing the
relative position of the shield and the path of radiant energy with
respect to one another to change the portion of each cycle during
which energy is supplied from the source of said receiver,
characterized by there being a second source of radiant energy and
a second radiation-responsive receiver in position to receive
energy from said second source, the radiant energy shield being in
position to shield both of the receivers from their sources of
energy, the control element being connected with both of the
receivers and both of the sources of energy and movable into
different positions to selectively alter the percent of each cycle
during which each path of radiant energy is obstructed by the
shield, and further characterized by the shield being a plate that
rotates about an axis, the control element including a bifurcated
lever that has portions that extend on opposite sides of the plate,
the receivers and sources of energy being carried by said lever
with each receiver on an opposite side of the plate from its source
of energy, each source and receiver being on a different side of
the axis of rotation of the plate so that swinging movement of the
lever moves one source and receiver away from the axis of rotation
of the plate and at the same time moves the other source and
receiver closer to the axis of rotation of the plate.
21. The control apparatus described in claim 20 characterized by
spring means that hold the lever in a neutral position in which the
shield has minimum effect on the path of radiant energy on both
sources and receivers, and spring means that oppose movement of the
lever from neutral position in either direction and that restore
the lever to its neutral position when the force displacing the
lever therefrom is released.
22. The control apparatus described in claim 21 characterized by
the different sources and receivers being in different electric
circuits, one of which connects with motor means for operating said
motor means in one direction and the other of which connects with
the same motor means but through connections that operate the motor
in the opposite direction.
23. The control apparatus described in claim 22 characterized by a
housing in which the plate, plate-driving motor, sources and
receivers are enclosed, the lever comprising a crank within the
housing, a shaft secured to the crank and extending through a
sidewall of the housing, and a handle portion of the lever secured
to the shaft outside of the housing.
24. The control apparatus described in claim 20 characterized by
there being a plurality of bifurcated levers at different angular
positions around the plate with receivers and sources of radiant
energy carried by each of the levers, and the receivers and sources
on each lever being connected in a different circuit from those of
any other lever.
25. The control apparatus described in claim 24 characterized by
each of the levers being movable independently of any other lever,
and a different handle portion connecting with each of the levers
and separate from the other handle portions, a housing in which the
plate, receivers and sources are enclosed, the handle portions
being outside of the housing and in position for manual operation
of the levers from outside of the housing.
26. Control apparatus for supplying different amounts of electrical
energy through a circuit in accordance with the displacement of a
control element, including in combination a source of radiant
energy, said source of radiant energy being an incandescent lamp, a
radiation-responsive receiver being light-responsive and being
located at a remote location from the lamp and being electrically
insulated from the environment of the lamp, a fiber optic bundle
with one end in position to receive light from said lamp and the
other end in position to transmit light to the light-responsive
receiver, a radiant energy shield between the source and the fiber
optic bundle in the environment of the lamp, said shield having a
peripheral edge movable into a position between the lamp and the
fiber optic bundle, said peripheral edge being of different radius
at angularly spaced locations along said peripheral edge, and motor
means connected with the shield for moving the shield through a
cycle, the control element being movable for changing the relative
position of the shield and the path of radiant energy to change the
portion of each cycle during which energy is supplied from the
source to the receiver, whereby movement of the control element
produces variable width pulses of energy at the receiver.
27. The control apparatus described in claim 26 characterized by
electric motor means to which energy is supplied from the receiver,
a mechanical element operated by the electric motor means into
different positions depending upon the amount of energy supplied
from the radiant energy source to the receiver, the energy received
by said motor means being in pulses having the frequency of the
cycle of the shield operation, and the total energy being a
function of the length of the pulse in each cycle, the mechanical
element being made more delicate in its operation as the result of
dither imparted thereto by the frequency of the energy pulses
supplied to said electric motor means.
28. The control apparatus described in claim 27 characterized by
the electric motor means being an electromagnet connected with the
mechanical element for pulling the mechanical element in one
direction, yielding loading means pulling the mechanical element in
the opposite direction whereby the position of the mechanical
element at any time depends upon the balance of the motor pull and
the opposite pull of the yielding load means.
29. The control apparatus described in claim 28 characterized by
the mechanical element being a poppet valve that controls flow of
fluid under pressure, the poppet valve being balanced as to the
pressure of the fluid that it controls.
Description
BACKGROUND AND SUMMARY OF THE INVENTION
This invention is an improved control apparatus for supplying
signals to an actuator; and the signals are modulated so as to
change the strength of the signal in proportion to the desired
position of the actuator. In order to obtain more reliable
operation so that the actuator responds equally well when moving as
when stationary, it is desirable to have a pulse signal of high
enough frequency so as to apply a dither to the actuator and the
mechanical element which the actuator moves.
The advantage of dither is that the mechanical parts are subjected
to vibration which reduces or eliminates static friction. Since
static friction is higher than dynamic friction, the reduction or
elimination of static friction makes the response of the actuator
to a particular signal much more uniform. The present invention
provides improved means for obtaining signals that provide
dither.
The use of light or other radiant energy, for pulse signals, is
well-known; and the advantages of the present invention are that
the signals can have higher frequency and by means of simple and
reliable shields the pulses can be modulated so as to produce a
signal of desired strength in accordance with the force required
from the actuator.
Sources of radiant energy, such as incandescent lamps, cannot be
lighted and extinguished quickly enough to obtain high frequency
pulses; but this invention uses a form of shield that rotates
rapidly. The light is maintained in a lit condition when the
control apparatus is being used; and the pulses are produced by
bringing a shield between the light and a light-responsive
receiver. This invention can utilize a source of radiant energy
which will be described as a "light," but which radiates at wave
lengths beyond the visible range. Incandescent lamps are the
preferred energy source because they produce a higher radiation
intensity at lower cost than other energy radiators; and are also
better suited for systems where the energy is to be carried by a
fiber optic bundle.
The preferred embodiment of the invention rotates a non-circular
plate, such as a square plate in such a way that the corners of the
plate shut off the light to the receiver every time one of the
corners passes across the path of the radiant energy. By changing
the distance from the axis of rotation of the plate to the path of
the radiant energy, the extent to which the plate intersects the
path of the radiant energy can be adjusted and this modulates the
pulses of radiant energy received by the light-responsive
receiver.
The light can be received first by a fiber optic bundle, located
behind the plate, and conveyed to a remote light-responsive
receiver in cases where it is desirable to obtain electrical
insulation of the ultimate receiver from the part of the apparatus
where the radiation source is located.
Other features of the invention relate to constructions by which
the source of radiant energy and the receiver are carried by a
common bifurcated lever which locates the source of radiant energy
on one side of the shield and the receiver on the other. The
bifurcated lever can carry two sets of sources and receivers and be
arranged so that movement of the lever in one direction controls
the apparatus to obtain movement of the actuator in one direction
whereas movement of the lever in the opposite direction effects
movement of the actuator in the opposite direction. Thus the
actuator is responsible to the direction of movement of the lever
that carries the sources and receivers of the radiant energy.
This invention also relates to various ways in which the modulated
pulse signaling means can be constructed for multiple controls and
with the apparatus of small size and miniaturized with various
expedients for modular combinations of the control apparatus.
Other objects, features and advantages of the invention will appear
or be pointed out as the description proceeds.
BRIEF DESCRIPTION OF DRAWING
In the drawing, forming a part hereof, in which like reference
characters indicate corresponding parts in all the views:
FIG. 1 is a diagrammatic view showing a portion of a control
mechanism of this invention and illustrating the way in which a
rotating shield is combined with the energy radiating elements to
control the pulses;
FIG. 2 is a view similar to FIG. 1 but showing the control
apparatus with the energy radiating source in a different position
to produce pulses when the shield rotates;
FIG. 3 is a view similar to FIG. 2 but showing the control
apparatus in condition to produce longer pulses than when in the
position shown in FIG. 2;
FIGS. 4, 5 and 6 are graphs showing the effect obtained with the
control apparatus in the position shown in FIGS. 1, 2 and 3,
respectively.
FIG. 7 is a view similar to FIG. 1, but showing a different form of
shield;
FIG. 8 is a detail view of a control apparatus made in accordance
with the principle illustrated in FIGS. 1-3;
FIG. 9 is an end view of the apparatus shown in FIG. 8;
FIGS. 10 and 11 are enlarged, sectional views taken on the lines
10--10 and 11--11, respectively, of FIG. 8;
FIG. 12 is a diagrammatic view showing the way in which modular
units such as shown in FIGS. 8 and 9 can be combined to make a more
elaborate control apparatus;
FIG. 13 is a rear view of the control apparatus shown in FIG.
12;
FIG. 14 is a plan view of one side of a modified control apparatus
made in accordance with this invention;
FIG. 15 is a side view of the apparatus shown in FIG. 14;
FIG. 16 is an enlarged end view of the apparatus shown in FIGS. 14
and 15, the view being taken from the right side of FIGS. 14 and
15;
FIG. 17 is a diagrammatic view showing the way in which the control
apparatus of this invention is combined with an actuator for a
mechanical element, such as a poppet valve; and
FIG. 18 is a diagrammatic view showing the invention with light
conveyed to the light-responsive means through a fiber optic
bundle.
DESCRIPTION OF PREFERRED EMBODIMENT
FIG. 1 shows a source of radiant energy 10, such as a lamp, carried
by a lever 12 which rocks about a fulcrum 14 and which is held in a
center neutral position by springs 16 and 16'. These springs press
against a handle portion 18 of the lever 12 and whenever the lever
is rocked clockwise or counterclockwise about its fulcrum 14, the
springs 16 and 16' restore the lever to its mid neutral position
whenever the force applied to the handle portion 18 is
released.
The lever 12 and the radiant energy source 10 comprise a control
element.
A shield or plate 22 is supported by an axle 24 for rotation about
the axis of the axle. Radial spacing of the energy source 10, when
the lever 12 is in its neutral position, is less than the minimum
radial dimension of the plate 22.
In the illustrated construction, the plate 22 is square and with
the plate in the position shown in full lines, the energy source 10
in some distance inward from the perimeter of the plate. Even when
the plate 22 is rotated 45.degree., as shown in broken lines, the
minimum dimension of the plate is adjacent to the energy source 10
but the energy source is still covered by the plate.
In the operation of the control apparatus, the axle 24 is rotated
by motor means, as indicated by the arrow 26. So long as the lever
12 remains in its mid or neutral position, as shown in FIG. 1, the
rotating plate 22 covers the energy source 10 and shields the
energy source so that none of the radiant energy can reach an
energy receiver, which will be described.
The lever 12, shown ig FIG. 2, also carries a second energy source
10' which is located on a different branch of the lever 12 from the
energy source 10, but at a symmetrical location so that when the
lever 12 is in its mid or neutral position, the energy source 10'
is always shielded by the plate 22.
If the handle portion 18 of the lever 12 is moved counterclockwise,
as shown in FIG. 2, the energy source 10 is moved further from the
axis of rotation of the axle 24 and its connected plate 22. The
energy source 10 is still covered by the plate 22 when a corner of
the plate is adjacent to the energy source 10. However, when the
minimum radial dimension of the plate 22 comes adjacent to the
energy source 10, as indicated by the broken line position of the
plate 22, the energy source 10 is only partially shielded by the
plate 22.
Thus rotation of the plate 22, when the energy source 10 is in the
position shown in FIG. 2, results in the energy source being
partially uncovered by the plate four times during each revolution
of the plate.
Movement of the handle portion 18 of the lever 12 further in a
counterclockwise direction, to the position shown in FIG. 3 moves
the energy source 10 still further from the axis of the axle 24.
The energy source 10 is now shielded by the plate 22 for only a
short time as each corner of the plate passes across the energy
source 10. During the rest of the time, the energy source 10 is
only partially shielded by the plate 10 and as the mid portion of
each side of the plate comes adjacent the energy source 10, the
plate exerts no shielding action on the energy source.
FIG. 4 is a graph representing one cycle of operation of the
control apparatus as shown in FIG. 1. This cycle is a complete
revolution of the axle 24 and its connected shield or plate 22. The
graph in FIG. 4 is divided into quadrants but the graph is uniform
throughout the entire cycle and shows that no radiant energy from
the source 10 is ever delivered to a receiver since the energy
source 10 is always shielded by the plate 22.
FIG. 5 shows the operation which results from the rotation of plate
22 with the lever 12 in the position shown in FIG. 2. The chart in
FIG. 5 begins at the zero angle which corresponds to the position
of the plate 22 shown in broken lines in FIG. 2. The shaded areas
of the graph represent time when radiant energy is being supplied
from the energy source 10 and not being shielded by the plate
22.
As the plate 22 rotates, the edge of the plate soon moves all the
way across the path of energy radiated by the energy source 10 and
the energy source is thus completely shielded as indicated by the
white area of FIG. 5. A corner of the plate 22 moves across the
energy source 10 at a time mid way between the zero and 90.degree.
indications on FIG. 5. As the mid portion of the next side of the
plate 22 approaches the energy source 10, the energy source is
uncovered part way and then covered again; the exposed period
indicated by the shaded area symmetrical about the 90.degree.
indication on FIG. 5.
In like manner pulses of energy are supplied from the partially
shielded energy source 10 at the regions of 180.degree.;
270.degree. and 360.degree.. Thus four signals of limited width are
supplied by the energy source 10 for each cycle (revolution) of the
plate 22.
FIG. 6 shows the difference in the width of the pulses radiated by
the energy source 10 when the lever 12 is in the position shown in
FIG. 3 as compared with the width of the pulses when the energy
source is closer to the axle 24 as in FIG. 2.
The energy pulses, indicated by the reference character 30 in FIG.
5 and by the reference character 30' in FIG. 6, have the same
frequency since the plate 22 is rotating at the same rate
regardless of the movement of the lever 12. The signal modulation
obtained by moving the lever 12 is a pulse width change and
represents an increased amount of radiant energy from the energy
source 10 for each pulse.
The rotary speed of the plate 22 is high enough so that the
frequency of the pulse signals 30 is high enough to produce a
desired dither in the actuator and the element operated by the
actuator under the control of the radiant signals.
It will be understood that if a different shape plate is used in
place of the plate 22, such as a hexagon instead of a square, the
number of signals for each cycle of the plate will be higher. Also
with certain actuators, it may be desirable to prevent the pulse
bands from ever decreasing to zero as in the case of FIG. 4. This
can be avoided, even with the plate 22, if notches are formed in
the sides of the plate, such as notches 32 shown in FIG. 7. These
notches form openings in a plate 22', which is otherwise the same
as the plate 22 of FIGS. 1-3, and the openings insure a narrow
pulse regardless of the position of the lever 12.
FIGS. 8-11 show the construction of control apparatus made in
accordance with the principle illustrated by FIGS. 1-3. Parts
corresponding to the parts in FIGS. 1-3 are indicated by the same
reference characters even though the parts are somewhat different
in shape but it should be understood that FIGS. 1-3 are merely
diagrammatic views of the control apparatus shown in FIGS.
8-10.
Referring first to FIG. 9, the lever 12 rocks about a fulcrum 14
near the top of a housing 36. The lever 12 is secured to one end of
the fulcrum 14 by a screw 38 which makes the lever 12 and fulcrum
14 an integral unit.
The fulcrum 14 is actually a short length of shaft extending
through a sidewall of the housing 36 as shown in FIG. 10. The
handle portion 18 of the lever 12 is an integral part of the
fulcrum 14 and in FIG. 10 is shown as being of one-piece
construction with the fulcrum 14 and located on the outside of the
housing 36 for convenient manipulation by an operator holding the
housing 36. The fulcrum 14 is actually a part of the lever 12 which
is offset from the lower portion of the lever so as to provide a
bearing surface on which the lever 12 can turn where it passes
through an opening 40 in the sidewall of the housing 36.
Referring again to FIG. 9, the lever 12 is bifurcated so that it
extends downwardly with portions on opposite sides of the plate 22.
The energy source 10 is carried by the bifurcation at the back of
the plate 22 and a radiant energy receiver which is responsive to
the energy from the source 10 is located on the other bifurcation
of lever 12 in front of the plate 10. This radiation responsive
receiver is indicated by the reference character 42 and it is in
alignment with the radiation source 10. There is a similar
radiation-responsive receiver 42' (FIG. 8) in line with the energy
source 10' (FIG. 3), the relationship being the same as that of the
energy source 10 and the energy receiver 42 in FIG. 9. However, the
energy source 10' and receiver 42' are not visible in FIG. 9 since
they are behind the source 10 and receiver 42.
The spring 16, for holding the lever 12 in a mid or neutral
position, is a coil spring surrounding the fulcrum shaft 14 and it
has its opposite ends 46 and 57 brought down behind spaced pins 48
and 49 which hold the spring 16 under tension with the pins 48 and
49 in a common plane. Rotation of the fulcrum shaft 14 in either
direction causes the pin 48, which moves as a unit with the lever
12, to displace either the end 46 or 47 of the spring 16, depending
upon the direction of displacement of the lever 12. Since the fixed
pin 49 prevents the other end of the spring from moving, there is
an increase in the pressure of the spring against the pin 48 urging
the pin 48 and the other parts of the lever 12 back into mid or
neutral position.
Referring to FIG. 8, it will be apparent that moving the handle
portion 18 counterclockwise affects the shielding of the
rotation-responsive receiver 42 from the energy source 10 (FIG. 9)
by the relative movement of the energy source with respect to the
axis of the axle 24 as already explained in connection with FIGS.
1-3. Movement of the handle portion 18 clockwise moves the other
energy source 10' (FIGS. 1-3) and energy receiver 42' (FIG. 8) with
respect to the axis of rotation of the plate 22 so that the plate
no longer shields the energy source 10' from the receiver 42' and
this provides a control which can be the opposite in effect; that
is, a reverse, of the control exerted by the surce 10 and receiver
42 (FIG. 9).
The modular control apparatus shown in FIGS. 8-11 has another lever
12a at the lower end of the housing 36 for controlling the position
of other radiation responsive receivers 42a and 42a' with respect
to the axile 24 of the plate 22. This lever 12a at the bottom of
the housing 36 is connected with elements which are the same as
those for the top lever 12 and it provides for different control
signals from the control apparatus.
FIGS. 12 and 13 show the modular control apparatus in the housng 36
connected with similar control apparatus in other modular housings
36-1, 36-2 and 36-3. It will be understood that as many such
housings can be connected together as desired. Each of these
housings has a plate 22 and has energy sources and receivers and
operating levers and other equipment the same as that described in
connection with FIGS. 8-10.
A motor housing 52 is connected to one end of the group of housings
36-36-3; and all of the plates 22 are driven by a motor 54 in the
motor housing 52. If the housing 36 and the apparatus contained
therein are used without the other housing 36-1, 36-2 and 36-3,
then the motor housing 52 is connected to the housing 36. No matter
how many housings are joined in a control apparatus assembly, only
one motor housing 52 is necessary.
The wiring to and from the energy sources and radiation-responsive
receivers in the housings 36-36-3 are carried to the motor housing
42 and from the housing 42 enter a cable 56 leading outward through
a connection 58 to the housing 52. This cable contains the
conductors from all of the sources and receivers in the housing
36-36-3 and these individual conductors terminate at separate
sockets 60 in a fitting 62 at the end of the cable 56 remote from
the motor housing 42. A complementary fitting, not shown, has pins
which extend into the sockets 60 and which join conductors in the
cable of the other fitting for leading to actuator motors or other
apparatus which is to be controlled. Such multi-connection fittings
are well-known and no illustration is necessary for a complete
understanding of this invention.
FIG. 12 shows a motor 66 digrammatically connected with the sockets
in the fitting 62 by conductors 68. These conductors 68 provide
power to the motor 62 for running the motor either forward or
reverse, depending upon which of the conducturs 68 are energized.
It will be understood that the connections to the motor, shown as
direct in FIG. 12 for simpler illustration, may be indirect through
amplifiers if the motor is large and the signal currents too weak
to provide the motored power directly.
FIGS. 14-16 show a modified form of the invention. Energy sources
and radiation-responsive receivers, one behind the other, are
indicated by FIG. 14 by the reference characters 70. These
source-receiver pairs are connected to bifurcated levers 71, 72 and
73 which rock about fulcrums 71f, 72f and 73f, respectively. The
fulcrums extend upwardly from a housing 75. The levers 71, 72 and
73 are of substantial height and are of bifurcated construction so
that they extend on opposite sides of a shielding plate 77 which is
shown in dotted lines in FIG. 14 and in solid lines in FIG. 15.
All of the levers 71, 72 and 73 are symmetrically located around an
axle 79 to which the plate 77 is connected, and this axle 79 is
rotated by a motor in the housing 75. Each of the levers 71, 72 and
73 has a spring 82 (FIG. 16) by which the lever 71, 72 or 73 is
held in a neutral position. The spring 82 is similar to the spring
16 shown in FIGS. 9-11.
The levers 71, 72 and 73 are rocked about their fulcrums 71f, 72f,
and 73f, respectively, by a handle 86 which has a grip portion 88
secured to a hollow shaft 90 extending upward through housing 75.
At the upper end of the hollow shaft 90 there is an adapter 92
which holds a pin 94. This pin 94 extends into slotted operating
cranks 96 and 98 which are attached to the levers 72 and 73,
respectively.
The hollow shaft 90 extends through a ring 100 (FIG. 16) and is
connected to the ring by a pin 101 on which the hollow shaft 90 has
rocking movement about the axis of the pin 101 in the plane on
which the section view of FIG. 16 is taken.
The ring 100 has aligned studs 104 projecting from its
circumference on diametrically opposite sides of the ring 100.
These studs 104 project into a fitting 106 which is a part of the
lower end of the housing 75 and there are bearings 108 in which the
ring 100 is free to rock about the axes of the cylindrical
projections 104. Because of the rocking movement of the pin 101 and
the projection 104, which are at right angles to one another, the
shaft 90 has universal rocking movement with respect to the housing
75.
The fitting 106 at the bottom of the housing 75 has limited rotary
movement with respect to the housing about the axis of the hollow
shaft 90. A crank arm 112 is of one-piece construction with the
fitting 106 and extends through a slot 114 in one side of the
housing 75. The length of this slot 114 determines the angle of
movement of the fitting 106. Rotation of the handle 86 about the
axis of the shaft 90 causes the crank 112 to move angularly along
the slot 114.
Referring again to FIG. 14, the operating crank 96 is secured to
the lever 72 by screws 120. The operating crank 98 is secured to
the lever 73 by screws 122. These screw connections make the
operating levers 96 and 98 an integral unit with their respective
levers 72 and 73.
When the handle is rocked to move the pin 94 in a direction
lengthwise of the slot through the operating crank 96, the crank 96
does not move and the lever 72 remains stationary; but the
operating lever 98 is moved and causes the lever 73 to rock about
its pivot 73f and to move its source and receiver pairs 70 with
respect to the axis of the plate shaft 79.
Similarly when the pin 94 moves in the direction of the slot in the
operating crank 98, the lever 73 does not move but the lever 72 is
rocked about its axis 72f. Movement of the pin 94 in any other
direction causes both of the operating cranks 96 and 98 to move
simultaneously; the degree of movement of each of these cranks
depending upon the direction of movement of the pin 94.
Thus the handle 86 can be operated with its universal rocking
movement to change the pulse width of the pulses generated by the
source and receiver pairs 70 carried by the levers 72 and 73. In
order to change the pulse widths controlled by the source and
receiver pairs 70 of the lever 71, the handle 86 is rotated about
its axis so as to move the crank 112 angularly about the axis of
the handle. There is an operating crank 124 extending from and
forming an integral part of the lever 71. This operating crank 124
is connected by a link 126 to the crank 112 so that angular
movement of the crank 112 produces corresponding angular movement
of the lever 71 about its fulcrum 71f.
In the construction illustrated there is a flexible boot 130 which
fits around the shaft 90 near the grip portion 88 and which has its
other end engaged in a circumferential groove 132 near the bottom
of the fitting 106. This boot 130 provides a seal closing the lower
end of the housing 75 and at the same time permits rotary and
rocking movement of the hollow shaft 90.
FIG. 17 is a diagrammatic showing of a valve 136 in a valve housing
138. When the valve is in closed position it shuts off the flow of
fluid from an inlet port 140 to an outlet port 142. The valve 136
is urged into closed position by a spring 144; and the valve has a
stem 146 extending through an electric coil 148.
When the coil 148 is energized, it attracts an armature 150 at the
end of the valve stem 46 and causes the armature 150 and valve stem
146 to move to the right, in FIG. 17, against the force of the
spring 144 so as to open the valve 136.
FIG. 17 shows the coil 148 energized from a battery in series with
the coil 148 and with the flow of current controlled by the
light-responsive receiver 42. It will be understood that the actual
circuit of the light responsive receiver 42 and the actuator coil
148 will include any necessary amplifiers and relays and other
usual equipment for circuits where light-responsive elements of
small capacity are used to control actuators requiring heavier
currents and greater variations in current than obtained in the
light-responsive controller 42.
FIG. 18 shows the bifurcated lever 71 of FIGS. 14 and 15 with the
shielding plate 77 extending between the elements of the enrgy
source and receiver pair 70. This energy source and receiver pair
include a radiant energy source 160 which is preferably an
incandescent lamp; and includes also an energy receiver 162 which
includes the upper end of a fiber optic bundle 164; the end faces
of the fibers being in position to receive light from the
incandescent lamp 160 when the light is not shielded from the
receiver 162 by the shielding plate 77.
The fiber optic bundle 164 leads to a light-responsive receiver 166
at a remote location from the bifurcated lever 71. In order to
permit free movement of the upper end of the bundle 164 to
accommodate movement of the lever 71, the portion of the bundle 164
adjacent to the lever 71 extends in a direction generally parallel
to the axis about which lever 71 rocks when operated to move it
about its fulcrum axis as already explained in connection with
FIGS. 14-16.
The light-responsive receiver 166 includes a photo transistor,
photo multiplier, or other light-responsive device in position to
receive light from the lower end of the fiber optic bundle 164.
This light-responsive receiver 166 also includes an amplifier and
such other circuitry as is conventional for using weak signals to
operate apparatus that requires considerably higher current
intensity.
The output from the light-responsive receiver 166 is supplied to a
coil 168 which is representative of a magnetic actuator, signal,
indicator, recording device, or other device which is to be
operated in response to the pulse energy transmitted through the
fiber optical bundle 164.
The preferred embodiment of the invention has been illustrated and
described, but changes and modifications can be made, and some
features can be used in different combinations without departing
from the invention as defined in the claims.
* * * * *