Aug. 21', 1934. L.'W. THOMPSON 1,971,204
Aug. 21', 1934.
L.'W. THOMPSON
’
1,971,204
ELECTRICAL RESISTANCE DEVICE~
Filed Feb. 25. 1932
Fig.
I
_20 22
m
v
25
Louis W. Thohwpsoh, by M.
‘
'
~
-
' His
Attgrnegf
1,971,204
vPatented A... 21, _1934
' UNITED STATES
PATENT OFFICE"
1.971.204 ' ELECTRICAL nasrs'mucs DEVICE
Louis W. Thompson, Schenectady, N. Y., assignor to General Electric Company, a corporation of . New York
. Application‘ February '25, 1932,'Serlal ‘No. 595,070 '
9. ‘Claims. (01. 201-455)
My invention relates to electrical resistance able materials being such vitreous compositions devices, and more particularly to improvements in electrical resistance devices of the type em-» ploying an electrical conducting ?uid. My invention is particularly adapted for use
as glass, pyrex,-.porcelain, etc. Container 2 is pivotally mounted on panel board 1 in any suit able manner andas shown, it is mounted in a frame 3, by means of straps 4, the frame 3 carry Oil
in automatic regulators employing a variable re
ing knife-edge projections 5, which cooperate
sistance device, although it may also be employed with suitably notched brackets 6, fastened to asl'a manually controlled variable resistance de vice. In. automatic regulators employing a vari .10 able resistance device in which a main control device is arranged to respond to variations in a
panel board‘ 1. Container 2 may take a variety ' of shapes so long as the lowermost parts of its _ cross section, taken perpendicular to its axis of a“
rotation, are internally substantially circular in' condition to'be regulated, it is usually desirable to shape. The simplest and perhaps the best shape
have a variable resistance device which is char
of. such a container is an elongated cylinder, is
acterized by ruggedness, long life, freedom from
illustrated.
,
,
Mounted in container 2 are a quantity of an 7‘) 5 contact arcing and deterioration, ease of move . ment from one extreme position to the other, and electrically conducting ?uid 7 and a solid elec
small amount of movement between extreme po— trical conductor 8. These conductors are so ar sitions corresponding respectively to the maxi ranged that when the container 2 is in one _posi tion the solid conductor will be in engagement In accordancewith my invention, I provide an with the ?uid conductor throughout substantially 75
mum and minimum resistance. '
.20
improved resistance device which is character
the entire'length of the solid conductor, while
lzed by the above featurés and which, in addition, when the container is rotated to another posi includes additional improved features which will tion, the solid conductor will ‘engage the ?uid 25 'be‘described more fully hereinafter.
conductor 'at substantially only a few points on
It “is an object of my invention to provide a; the solid conductor. The ?uid and solid con ductors may both be composed of electrical re new and’ improved electrical resistance device. It is another object of my invention to provide an electrical resistance device which is charac _ terized by long life, minimum mechanical resist 30 ance to change of electrical resistance, and .a minimum required mechanical movement for a
sistance material or either one alone may be
composed of relatively high resistance material while the other is of relatively low resistance
material. I have found, however, that best re sults are obtained when the ?uid. conductor is of > relatively low electrical resistance as compared maximum change in electrical resistance. My invention will be better understood from with the electrical resistance of the solid con the following description‘ taken in connection ductor. Thus, in a preferred arrangement of my 35 with the accompanying drawing, and its scope invention, the fluid conductor 7 is liquid mer- 90 ‘ will be pointed out in the appended claims.’ cury, while the solid conductor 8 may be any _ In the drawing, Fig. Us a front elevation, partly well known relatively. highv resistance material. in section, of an automatic voltage-regulator em Resistance conductor 8 may be of almost any de ploying my invention; Fig. 2 is an end elevation sired type or shape, but I'havefound that good 40 of the regulator shown in Fig. l, as viewed from results are obtained when it is in the form of a 95 the left-hand end of Fig. 1; Fig. 3 is an enlarged resistance wire which is wound ona suitablev sup detail section of my resistance regulator taken on porting means which I have illustrated as an in line 3-3 of Fig. 1; Fig. 4 is a longitudinal sec . sulating strip 9. Resistance wire. 8 and strip 9 tional view of Jmy resistance regulator taken may together be taken as a solid resistance and 100 45 when the resistance element thereof is in a vertil ‘this combination is so mounted in container 2 cal position, and Fig. 5 is a sectional view .of that itscontact boundary is in parallel/relation K Fig. 4 taken on the line 5-5 of Fig. 4. > with the longitudinal axis of the container. As ' Referring now to the drawirfg,. wherein the shown, the resistance element is so mounted that its longitudinal axis makes a relatively small same reference characters denote the same ele 50 ments throughout the various ?gures, and refer ' angle with the .axis of rotation of the container. 105 ring particularly to Figs. 1 and 2, I show a panel A convenient way of mounting the combination board 1, of any suitable vmaterial, on'which to of resistance wire 8 and supporting strip 9, is by _mount the regulator. Mounted on panel 1 is a meansof metallic plate members 10 which are I container, or envelope 2, which is preferably
55 made of an electrical'i'nsulating materiaLsuit
of a. circular shape and of such a size as to ?t
snugly within the container 2. As shown clearly 110
2
1,971,204
in‘ Fig. 4, the longitudinal axis of the solid re sistance element, comprising the wire 8 wound on the support 9, makes a small angle with the axis of rotation of the container. It is by means of this angle that rotation of the container will
tinct improvement in operation results.
These
ba?ies may be supported in any suitable way and as shown I provide wires, or rods, 17 for this pur pose. These wires are fastened to the end sup
80
porting plates 10.
With the resistance device described above, it cause varying degrees of submergence, or progres sively changing points of contact, 0 the solid will be seen that in no position can the resistance resistance material in or with the liquid con of the regulator exceed the combined resistances ducting material. As shown in Figs. 1, 2 and 3, of the resistance wire 8 and the return circuit the container 2 is in such a position that the re through the liquid. This is because even if the 85 sistance wire 84s just making contact with the resistance wire 8 is entirely out of contact with mercury 'l at the left-hand end of the resistance. the mercury‘, the return circuit will always be It now the container 2 is rotated in a clockwise made through the left-hand end plate 10 to the direction as viewed in Figs. 2 ‘and 3, the direc mercury. This is a distinct advantage as it pre vents accidentally open circuiting a regulating 15 tion of motion of the contact boundary of re
sistance 8 will be substantially at right angles to circuit including the regulating resistance. It will also be noted that as the container 2 its longitudinal axis and the point of contact be tween resistance 8 and the surface of the mercury is rotated . from its position corresponding to will move toward the right thereby causing suc maximum resistance to its position corresponding to minimum resistance of the regulator, the length 95 20 cessive engagement of the turns of the resistance of the electrical conducting paths through the wire with the mercury. ‘ , The left-hand end of resistancewire 8 is elec solid and the liquid conductors vary simu‘tane trically connected at 11 to the metal supporting’ ously and similarly, that is to say, their maximum plate 10 so that this end of the resistance wire and minimum lengths occur together. While The - this is not of much advantage in cases where 100 right-hand end of the‘resistance wire 8 is con the ?uid conductor is mercury, because of the nected to a terminal 12 which is insulated from relatively low resistance of this liquid, it is of
is in electrical contact with the mercury '7‘.
‘the right-hand supporting member 10. Another considerable advantage in cases where the elec terminal 13 is electrically connected to the sup trical resistance of the solid and fluid conductors are substantially equal. 30 porting means 10. Lead-in wires 14 connect Another advantageous result which I obtain respectively to the terminals 12 and 13 and these is that the ?uid, or liquid, conductor does "not have to be moved in changing the resistance of
lead-in wires 14 are sealed into the walls of the container in a manner similar to that in which the lead-in wires to an ordinary incandescent electric light bulb are sealed in.
the regulator and consequently the inertia forces produced when the regulator goes from one po 110
with these connections'and with the resistance regulator in the position shown'in Figs. 1, 2 and 3, an electrical circuit through the regulator will‘ begin, for example, at terminal 12, traverse sub
mercury, the remaining elements will be relatively light in comparison with the mercury.
sition to the other may be made relatively low because in cases when the liquid conductor is
It will also be seen that my resistance regu 115 stantially all of the resistance wire 8 and return through the mercury to the terminal 13. As the lator will be balanced in any position so that it container 2 is rotated in a clockwise direction, will require but a relatively small and uniformv as viewed in Figs. 2 and 3, the point of contact force to change it from any one position to an
of ‘the resistance .and the mercury is moved to the right, thereby short circuiting successive turns of the resistance 8 and reducing simultaneously the length of the conducting path through both the resistance wire ‘8 and the conducting liquid 7. In assembling the regulator, the container 2 will be open at its right-hand end and the strip 9 with its attached supports 10 will he slid into the container, electrical connections will then be completed between the lead-in wires 14 and the terminals 12 and 13 respectively, and then the container will be sealed at points 15.
.
other. As shown in Fig. 1, I have illustrated an ap 120 plication of my invention to an automatic elec tric voltage regulator. In this ?gure a solenoid magnet 18 is connected across a circuit 19 whose
voltage is to be regulated. The core 18:; of sole noid magnet 18 is mechanically connected to the 125 frame 3 for operating my resistance device. A suitable rheostat 20 is connected in the energiz ing circuit of solenoid 18 for adjusting the voltage
calibration of this solenoid. For energizing cir cult-19 I have illustrated a direct current gen 130
In order to .prevent oxidation and deteriora erator 21 having a shunt field winding 22 whose tion of the resistance wire 8 and also to prevent circuit is connected to the terminals 14 of my - arcing between the resistance wire and the mer resistance device. A conventional shunt field cury, the container 2 may be evacuated or it rheostat 23_is also- provided in the shunt field may be_-fllled with an atmosphere of oxidation winding circuit of the generator. A restraining preventing gas. This, gas may actually be‘a re spring 24, for opposing the pull of ‘solenoid 18, is ducing gas such as hydrogen or it may be a relatively inert gas such as argon, helium or nitrogen.
‘
connected to the frame 3.
-
. The solenoid 18 is made extra large and power ' ful so that‘it will develop operating forces on
I have found that with the above described changes of voltage of circuit 19 which are suf
arrangement relatively sudden changes in the ficiently large to readily and quickly rotate my angular position of the container 2, which result resistance device. The core 180 of the solenoid
140
in varying the degree of engagement of the re sistance wire on strip 9 with the liquid in the is so arranged that as it is pulled up into the magnet from its lowermost position it enters a 70 container, cause traveling ripples to move along stronger and stronger magnetic field, so that with 145 the surface of the liquid. These traveling rip ples cause undesirable and uncontrollable resist a constant voltage applied to the terminals of ance changes. By providing one or more spaced the operating magnet the pull on the solenoid bailles 16 which extend into the liquid conductor, core increases as the core moves up into the mag net. If ?at regulation is desired spring 24 is 150 75 these ripples are eifectivelybroken up and a dis
1,971,204’
3
so constructed that its change in pull, as a is tive movement therewith, and an electrical re stretched due to the rotation of the resistance sistance within said‘container in fixed relation device, exactly equals the ‘change in pull of the therewith and having a longitudinal contact ‘solenoid magnet resulting from its change of po boundary substantially co-extensive with one of sition- This is because with suchan arrange the dimensions of the surface of said liquid and 80 ment of solenoid and spring the pulls of the two arranged so that points of contact with said liquid devices will exactly balance each other at any change progressively along said boundary in ac position of the resistance device, so long as con cordance with the relative movement between said stant voltage is applied to the‘ operating magnet. ?uid and container. ‘ . _ 3. In combination, a substantially horizontal 85 10 If a weaker spring is used, an over-compounding effect may be obtained which is useful in cases cylindrical container, a relatively low resistance where it is desirable to compensate for line drop. electrical conducting liquid partially ?lling said If a stronger spring is used, an under-com pounding effect will be obtained and this effect 15 is useful for producing stable operation in cases where a plurality of regulated generators are
container, means for rotating said container about its longitudinal axis, a relatively high resistance -
electrical conducting element mounted in said container in such a manner that said rotation
causes varying degrees of submergence of said
- connected in parallel.
As shown in Fig. 1, the core 18a is in its upper element in said liquid, said element having a con most position and the resistance device is in its tact boundary making a small angle with the 20 maximum resistance position. Assume, however, 'that- these devices are in substantially their mid
surface of said liquid.
,
dle positions and that the voltage on circuit 19 a solid electrical conductor mounted for variable is normal. If now ‘circuit conditions should engagement with said liquid conductor, and a change, for example, if the load on circuit 19v bailie normally associated with the surface of said 25 should'increase, the voltage of circuit 19 would liquid conductor for breaking up traveling ripples decrease thereby decreasing the pull of the sole on the surface of said liquid conductor. - noid 18, and allowing the spring to overcome ' the pull of the solenoid, thereby rotating the re
95
4. In combination, a liquid electrical conductor,
100
will balance each other. Similarly, if the voltage of circuit 19- increases, the pull of solenoid 18 increases, thereby rotating the resistance device
‘5. In combination, a liquid electrical'conductor, a solid electrical resistance element arranged variably to engage the surface of said liquid along the length of said conductor at an effective angle 105 with respect to the surface of said liquid which is small, and spaced baffles associated with the sur face of said liquid for breaking up traveling ripples on the surface of said liquid. 6. In combination, an elongated glass tube, supporting means for maintaining the longitudi nal axis of said tube substantially horizontal and for permitting rotation of said tube about said ‘axis, a strip of insulating material mounted in
40 in the opposite direction and ‘increasing the value
said tube in such a manner that its longitudinal 115
sistance device and decreasing its resistance. 30 This increases the‘ current through the ?eld wind
ing 22, thereby increasing the voltage of gen~
orator 1 and increasing the voltage of circuit 19. As soon as the voltage of circuit 19 returns to normal, the regulator will come to rest in its bal 35 anced position because in this new position the pull‘ of the spring and the pull of the solenoid
of the resistance of the resistance device, thereby. axis makes a relatively small angle with the axis ' decreasing the voltage of the generator 21. When of said tube, an electrical resistance wire wound the voltage returns to normal the regulator will on said strip, a su?icient quantity of liquidmer balance in its new position. ' cury in said tube to cause engagement between In order to-prevent hunting of the regulator-I said mercury ‘and substantially all of the turns 120 45 provide a suitable dashpot mechanism 25, which of said resistance wire when said strip is verti is connected through a spring 26 to frame 3. In cal, bailles placed at intervalsin said tube to troduction of spring 26 is to permit rapid, rela break up longitudinally traveling ripples on the tively small changes in resistance of the regulator, surface of said mercury, and an atmosphere of gas in said tube. 125 ‘so thus increasing the speed of operation of the reducing '7. In combination, a straight elongated glass While I have shown and described a particular tube having its longitudinal axis substantially embodiment of my'invention, it will be obvious to horizontal, supporting means for permitting rota those skilled in'the art that changes and modi?ca tion of said tube about its longitudinal axis, a tions may be made without departing from my straight relatively thin elongated rectangular 130 55 invention, and I therefore aim in the appended strip of insulating material rigidly mounted in claims to cover all such changes and modifications said tube with its longitudinal axis making a rela as fall within the true spirit and scope of my tively small angle with the longitudinal axis of said tube, a resistance wire wound ‘around said regulator.
invention.
'
'
.
I
.
'
'
'
What I claim as new and desire to secure by
Letters Patent in the United States is: 1. A variable resistance device comprising a horizontaltubular container having a longitudi nal axis of rotation, an electrical conducting fluid partially ?lling said container to a substantially constant level andarranged‘ for relative move ment with said container, and an electrical resist-
strip substantially perpendicularly to its longi 130
tudinal axis, a suflicient quantity of liquid mer
cury in said tube to just permit engagement be - tween said mercury and a portion of substantially
each of the turns of said resistance wire when said strip is in a substantially vertical position, 140 baffle plates mounted at intervals in said tube in engagement with the surface 'of said mercury; ance within said container in ?xed relation there- - and an atmosphere of oxidation preventing gas with and having a longitudinal contact boundary in said tube. ' ' 8. In combination, a container mounted'for 145 70 for engagement with said fluid, said contact boun dary making an acute angle with the longitudinal rotation about a horizontal axis and having the inside bottom surface thereof in the shape of a axis of said container. 2. A variable resistance device comprising a cylinder whose axis corresponds with the axis of ‘
container, an electrical conducting liquid par 75 tially ?lling said container and arranged for rela
said container, a resistance element having the substantial equivalent of a straight line contact 150
4
1,971,204
boundari mounted in said container with a small angle between said boundary/and said axis, and a quantity of conducting liquid in said container for engagement withsaid contact boundary.
said container, said strip having one edge which
is a straight line making a small angle with said axis, a resistance wire wound around said strip, and a. quantity of conducting liquid in said con 9. In combination, a tubular container mounted tainer for engagement with said resistance wire. 80
_,horizontally Ior rotation about its longitudinal axis, a strip of insulating material mounted in
LOUIS w. momson.
10
ll
20
95
100
30
105
35
110
40
110
45
120
125
130
135
140
14b
75
L.'W. THOMPSON
’
1,971,204
ELECTRICAL RESISTANCE DEVICE~
Filed Feb. 25. 1932
Fig.
I
_20 22
m
v
25
Louis W. Thohwpsoh, by M.
‘
'
~
-
' His
Attgrnegf
1,971,204
vPatented A... 21, _1934
' UNITED STATES
PATENT OFFICE"
1.971.204 ' ELECTRICAL nasrs'mucs DEVICE
Louis W. Thompson, Schenectady, N. Y., assignor to General Electric Company, a corporation of . New York
. Application‘ February '25, 1932,'Serlal ‘No. 595,070 '
9. ‘Claims. (01. 201-455)
My invention relates to electrical resistance able materials being such vitreous compositions devices, and more particularly to improvements in electrical resistance devices of the type em-» ploying an electrical conducting ?uid. My invention is particularly adapted for use
as glass, pyrex,-.porcelain, etc. Container 2 is pivotally mounted on panel board 1 in any suit able manner andas shown, it is mounted in a frame 3, by means of straps 4, the frame 3 carry Oil
in automatic regulators employing a variable re
ing knife-edge projections 5, which cooperate
sistance device, although it may also be employed with suitably notched brackets 6, fastened to asl'a manually controlled variable resistance de vice. In. automatic regulators employing a vari .10 able resistance device in which a main control device is arranged to respond to variations in a
panel board‘ 1. Container 2 may take a variety ' of shapes so long as the lowermost parts of its _ cross section, taken perpendicular to its axis of a“
rotation, are internally substantially circular in' condition to'be regulated, it is usually desirable to shape. The simplest and perhaps the best shape
have a variable resistance device which is char
of. such a container is an elongated cylinder, is
acterized by ruggedness, long life, freedom from
illustrated.
,
,
Mounted in container 2 are a quantity of an 7‘) 5 contact arcing and deterioration, ease of move . ment from one extreme position to the other, and electrically conducting ?uid 7 and a solid elec
small amount of movement between extreme po— trical conductor 8. These conductors are so ar sitions corresponding respectively to the maxi ranged that when the container 2 is in one _posi tion the solid conductor will be in engagement In accordancewith my invention, I provide an with the ?uid conductor throughout substantially 75
mum and minimum resistance. '
.20
improved resistance device which is character
the entire'length of the solid conductor, while
lzed by the above featurés and which, in addition, when the container is rotated to another posi includes additional improved features which will tion, the solid conductor will ‘engage the ?uid 25 'be‘described more fully hereinafter.
conductor 'at substantially only a few points on
It “is an object of my invention to provide a; the solid conductor. The ?uid and solid con ductors may both be composed of electrical re new and’ improved electrical resistance device. It is another object of my invention to provide an electrical resistance device which is charac _ terized by long life, minimum mechanical resist 30 ance to change of electrical resistance, and .a minimum required mechanical movement for a
sistance material or either one alone may be
composed of relatively high resistance material while the other is of relatively low resistance
material. I have found, however, that best re sults are obtained when the ?uid. conductor is of > relatively low electrical resistance as compared maximum change in electrical resistance. My invention will be better understood from with the electrical resistance of the solid con the following description‘ taken in connection ductor. Thus, in a preferred arrangement of my 35 with the accompanying drawing, and its scope invention, the fluid conductor 7 is liquid mer- 90 ‘ will be pointed out in the appended claims.’ cury, while the solid conductor 8 may be any _ In the drawing, Fig. Us a front elevation, partly well known relatively. highv resistance material. in section, of an automatic voltage-regulator em Resistance conductor 8 may be of almost any de ploying my invention; Fig. 2 is an end elevation sired type or shape, but I'havefound that good 40 of the regulator shown in Fig. l, as viewed from results are obtained when it is in the form of a 95 the left-hand end of Fig. 1; Fig. 3 is an enlarged resistance wire which is wound ona suitablev sup detail section of my resistance regulator taken on porting means which I have illustrated as an in line 3-3 of Fig. 1; Fig. 4 is a longitudinal sec . sulating strip 9. Resistance wire. 8 and strip 9 tional view of Jmy resistance regulator taken may together be taken as a solid resistance and 100 45 when the resistance element thereof is in a vertil ‘this combination is so mounted in container 2 cal position, and Fig. 5 is a sectional view .of that itscontact boundary is in parallel/relation K Fig. 4 taken on the line 5-5 of Fig. 4. > with the longitudinal axis of the container. As ' Referring now to the drawirfg,. wherein the shown, the resistance element is so mounted that its longitudinal axis makes a relatively small same reference characters denote the same ele 50 ments throughout the various ?gures, and refer ' angle with the .axis of rotation of the container. 105 ring particularly to Figs. 1 and 2, I show a panel A convenient way of mounting the combination board 1, of any suitable vmaterial, on'which to of resistance wire 8 and supporting strip 9, is by _mount the regulator. Mounted on panel 1 is a meansof metallic plate members 10 which are I container, or envelope 2, which is preferably
55 made of an electrical'i'nsulating materiaLsuit
of a. circular shape and of such a size as to ?t
snugly within the container 2. As shown clearly 110
2
1,971,204
in‘ Fig. 4, the longitudinal axis of the solid re sistance element, comprising the wire 8 wound on the support 9, makes a small angle with the axis of rotation of the container. It is by means of this angle that rotation of the container will
tinct improvement in operation results.
These
ba?ies may be supported in any suitable way and as shown I provide wires, or rods, 17 for this pur pose. These wires are fastened to the end sup
80
porting plates 10.
With the resistance device described above, it cause varying degrees of submergence, or progres sively changing points of contact, 0 the solid will be seen that in no position can the resistance resistance material in or with the liquid con of the regulator exceed the combined resistances ducting material. As shown in Figs. 1, 2 and 3, of the resistance wire 8 and the return circuit the container 2 is in such a position that the re through the liquid. This is because even if the 85 sistance wire 84s just making contact with the resistance wire 8 is entirely out of contact with mercury 'l at the left-hand end of the resistance. the mercury‘, the return circuit will always be It now the container 2 is rotated in a clockwise made through the left-hand end plate 10 to the direction as viewed in Figs. 2 ‘and 3, the direc mercury. This is a distinct advantage as it pre vents accidentally open circuiting a regulating 15 tion of motion of the contact boundary of re
sistance 8 will be substantially at right angles to circuit including the regulating resistance. It will also be noted that as the container 2 its longitudinal axis and the point of contact be tween resistance 8 and the surface of the mercury is rotated . from its position corresponding to will move toward the right thereby causing suc maximum resistance to its position corresponding to minimum resistance of the regulator, the length 95 20 cessive engagement of the turns of the resistance of the electrical conducting paths through the wire with the mercury. ‘ , The left-hand end of resistancewire 8 is elec solid and the liquid conductors vary simu‘tane trically connected at 11 to the metal supporting’ ously and similarly, that is to say, their maximum plate 10 so that this end of the resistance wire and minimum lengths occur together. While The - this is not of much advantage in cases where 100 right-hand end of the‘resistance wire 8 is con the ?uid conductor is mercury, because of the nected to a terminal 12 which is insulated from relatively low resistance of this liquid, it is of
is in electrical contact with the mercury '7‘.
‘the right-hand supporting member 10. Another considerable advantage in cases where the elec terminal 13 is electrically connected to the sup trical resistance of the solid and fluid conductors are substantially equal. 30 porting means 10. Lead-in wires 14 connect Another advantageous result which I obtain respectively to the terminals 12 and 13 and these is that the ?uid, or liquid, conductor does "not have to be moved in changing the resistance of
lead-in wires 14 are sealed into the walls of the container in a manner similar to that in which the lead-in wires to an ordinary incandescent electric light bulb are sealed in.
the regulator and consequently the inertia forces produced when the regulator goes from one po 110
with these connections'and with the resistance regulator in the position shown'in Figs. 1, 2 and 3, an electrical circuit through the regulator will‘ begin, for example, at terminal 12, traverse sub
mercury, the remaining elements will be relatively light in comparison with the mercury.
sition to the other may be made relatively low because in cases when the liquid conductor is
It will also be seen that my resistance regu 115 stantially all of the resistance wire 8 and return through the mercury to the terminal 13. As the lator will be balanced in any position so that it container 2 is rotated in a clockwise direction, will require but a relatively small and uniformv as viewed in Figs. 2 and 3, the point of contact force to change it from any one position to an
of ‘the resistance .and the mercury is moved to the right, thereby short circuiting successive turns of the resistance 8 and reducing simultaneously the length of the conducting path through both the resistance wire ‘8 and the conducting liquid 7. In assembling the regulator, the container 2 will be open at its right-hand end and the strip 9 with its attached supports 10 will he slid into the container, electrical connections will then be completed between the lead-in wires 14 and the terminals 12 and 13 respectively, and then the container will be sealed at points 15.
.
other. As shown in Fig. 1, I have illustrated an ap 120 plication of my invention to an automatic elec tric voltage regulator. In this ?gure a solenoid magnet 18 is connected across a circuit 19 whose
voltage is to be regulated. The core 18:; of sole noid magnet 18 is mechanically connected to the 125 frame 3 for operating my resistance device. A suitable rheostat 20 is connected in the energiz ing circuit of solenoid 18 for adjusting the voltage
calibration of this solenoid. For energizing cir cult-19 I have illustrated a direct current gen 130
In order to .prevent oxidation and deteriora erator 21 having a shunt field winding 22 whose tion of the resistance wire 8 and also to prevent circuit is connected to the terminals 14 of my - arcing between the resistance wire and the mer resistance device. A conventional shunt field cury, the container 2 may be evacuated or it rheostat 23_is also- provided in the shunt field may be_-fllled with an atmosphere of oxidation winding circuit of the generator. A restraining preventing gas. This, gas may actually be‘a re spring 24, for opposing the pull of ‘solenoid 18, is ducing gas such as hydrogen or it may be a relatively inert gas such as argon, helium or nitrogen.
‘
connected to the frame 3.
-
. The solenoid 18 is made extra large and power ' ful so that‘it will develop operating forces on
I have found that with the above described changes of voltage of circuit 19 which are suf
arrangement relatively sudden changes in the ficiently large to readily and quickly rotate my angular position of the container 2, which result resistance device. The core 180 of the solenoid
140
in varying the degree of engagement of the re sistance wire on strip 9 with the liquid in the is so arranged that as it is pulled up into the magnet from its lowermost position it enters a 70 container, cause traveling ripples to move along stronger and stronger magnetic field, so that with 145 the surface of the liquid. These traveling rip ples cause undesirable and uncontrollable resist a constant voltage applied to the terminals of ance changes. By providing one or more spaced the operating magnet the pull on the solenoid bailles 16 which extend into the liquid conductor, core increases as the core moves up into the mag net. If ?at regulation is desired spring 24 is 150 75 these ripples are eifectivelybroken up and a dis
1,971,204’
3
so constructed that its change in pull, as a is tive movement therewith, and an electrical re stretched due to the rotation of the resistance sistance within said‘container in fixed relation device, exactly equals the ‘change in pull of the therewith and having a longitudinal contact ‘solenoid magnet resulting from its change of po boundary substantially co-extensive with one of sition- This is because with suchan arrange the dimensions of the surface of said liquid and 80 ment of solenoid and spring the pulls of the two arranged so that points of contact with said liquid devices will exactly balance each other at any change progressively along said boundary in ac position of the resistance device, so long as con cordance with the relative movement between said stant voltage is applied to the‘ operating magnet. ?uid and container. ‘ . _ 3. In combination, a substantially horizontal 85 10 If a weaker spring is used, an over-compounding effect may be obtained which is useful in cases cylindrical container, a relatively low resistance where it is desirable to compensate for line drop. electrical conducting liquid partially ?lling said If a stronger spring is used, an under-com pounding effect will be obtained and this effect 15 is useful for producing stable operation in cases where a plurality of regulated generators are
container, means for rotating said container about its longitudinal axis, a relatively high resistance -
electrical conducting element mounted in said container in such a manner that said rotation
causes varying degrees of submergence of said
- connected in parallel.
As shown in Fig. 1, the core 18a is in its upper element in said liquid, said element having a con most position and the resistance device is in its tact boundary making a small angle with the 20 maximum resistance position. Assume, however, 'that- these devices are in substantially their mid
surface of said liquid.
,
dle positions and that the voltage on circuit 19 a solid electrical conductor mounted for variable is normal. If now ‘circuit conditions should engagement with said liquid conductor, and a change, for example, if the load on circuit 19v bailie normally associated with the surface of said 25 should'increase, the voltage of circuit 19 would liquid conductor for breaking up traveling ripples decrease thereby decreasing the pull of the sole on the surface of said liquid conductor. - noid 18, and allowing the spring to overcome ' the pull of the solenoid, thereby rotating the re
95
4. In combination, a liquid electrical conductor,
100
will balance each other. Similarly, if the voltage of circuit 19- increases, the pull of solenoid 18 increases, thereby rotating the resistance device
‘5. In combination, a liquid electrical'conductor, a solid electrical resistance element arranged variably to engage the surface of said liquid along the length of said conductor at an effective angle 105 with respect to the surface of said liquid which is small, and spaced baffles associated with the sur face of said liquid for breaking up traveling ripples on the surface of said liquid. 6. In combination, an elongated glass tube, supporting means for maintaining the longitudi nal axis of said tube substantially horizontal and for permitting rotation of said tube about said ‘axis, a strip of insulating material mounted in
40 in the opposite direction and ‘increasing the value
said tube in such a manner that its longitudinal 115
sistance device and decreasing its resistance. 30 This increases the‘ current through the ?eld wind
ing 22, thereby increasing the voltage of gen~
orator 1 and increasing the voltage of circuit 19. As soon as the voltage of circuit 19 returns to normal, the regulator will come to rest in its bal 35 anced position because in this new position the pull‘ of the spring and the pull of the solenoid
of the resistance of the resistance device, thereby. axis makes a relatively small angle with the axis ' decreasing the voltage of the generator 21. When of said tube, an electrical resistance wire wound the voltage returns to normal the regulator will on said strip, a su?icient quantity of liquidmer balance in its new position. ' cury in said tube to cause engagement between In order to-prevent hunting of the regulator-I said mercury ‘and substantially all of the turns 120 45 provide a suitable dashpot mechanism 25, which of said resistance wire when said strip is verti is connected through a spring 26 to frame 3. In cal, bailles placed at intervalsin said tube to troduction of spring 26 is to permit rapid, rela break up longitudinally traveling ripples on the tively small changes in resistance of the regulator, surface of said mercury, and an atmosphere of gas in said tube. 125 ‘so thus increasing the speed of operation of the reducing '7. In combination, a straight elongated glass While I have shown and described a particular tube having its longitudinal axis substantially embodiment of my'invention, it will be obvious to horizontal, supporting means for permitting rota those skilled in'the art that changes and modi?ca tion of said tube about its longitudinal axis, a tions may be made without departing from my straight relatively thin elongated rectangular 130 55 invention, and I therefore aim in the appended strip of insulating material rigidly mounted in claims to cover all such changes and modifications said tube with its longitudinal axis making a rela as fall within the true spirit and scope of my tively small angle with the longitudinal axis of said tube, a resistance wire wound ‘around said regulator.
invention.
'
'
.
I
.
'
'
'
What I claim as new and desire to secure by
Letters Patent in the United States is: 1. A variable resistance device comprising a horizontaltubular container having a longitudi nal axis of rotation, an electrical conducting fluid partially ?lling said container to a substantially constant level andarranged‘ for relative move ment with said container, and an electrical resist-
strip substantially perpendicularly to its longi 130
tudinal axis, a suflicient quantity of liquid mer
cury in said tube to just permit engagement be - tween said mercury and a portion of substantially
each of the turns of said resistance wire when said strip is in a substantially vertical position, 140 baffle plates mounted at intervals in said tube in engagement with the surface 'of said mercury; ance within said container in ?xed relation there- - and an atmosphere of oxidation preventing gas with and having a longitudinal contact boundary in said tube. ' ' 8. In combination, a container mounted'for 145 70 for engagement with said fluid, said contact boun dary making an acute angle with the longitudinal rotation about a horizontal axis and having the inside bottom surface thereof in the shape of a axis of said container. 2. A variable resistance device comprising a cylinder whose axis corresponds with the axis of ‘
container, an electrical conducting liquid par 75 tially ?lling said container and arranged for rela
said container, a resistance element having the substantial equivalent of a straight line contact 150
4
1,971,204
boundari mounted in said container with a small angle between said boundary/and said axis, and a quantity of conducting liquid in said container for engagement withsaid contact boundary.
said container, said strip having one edge which
is a straight line making a small angle with said axis, a resistance wire wound around said strip, and a. quantity of conducting liquid in said con 9. In combination, a tubular container mounted tainer for engagement with said resistance wire. 80
_,horizontally Ior rotation about its longitudinal axis, a strip of insulating material mounted in
LOUIS w. momson.
10
ll
20
95
100
30
105
35
110
40
110
45
120
125
130
135
140
14b
75
