US949465A - Antiphase reversing device. - Google Patents
Antiphase reversing device. Download PDFInfo
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- US949465A US949465A US1906324541A US949465A US 949465 A US949465 A US 949465A US 1906324541 A US1906324541 A US 1906324541A US 949465 A US949465 A US 949465A
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- switch
- motor
- main line
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- current
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B66—HOISTING; LIFTING; HAULING
- B66B—ELEVATORS; ESCALATORS OR MOVING WALKWAYS
- B66B1/00—Control systems of elevators in general
- B66B1/02—Control systems without regulation, i.e. without retroactive action
- B66B1/06—Control systems without regulation, i.e. without retroactive action electric
- B66B1/08—Control systems without regulation, i.e. without retroactive action electric with devices, e.g. handles or levers, in the cars or cages for direct control of movements
Definitions
- My invention relates to a safety device for interrupting electric circuits and although it is herein shown applied to motor-control ling circuits of an elevator system, it may have a general application.
- the primary object of my invention is the provision of automatic means for interrupt ing the connection between the source of power and a translating device when the latter does not operate as desired.
- Another object of my invention is the provision, in an elevator system, of means for ctmtrolling the openingof the main line switch for the motor, from a predetermined point.
- the invention is particularly adapted to be used in connection with a torque-release brake such as described in my co-pending application, Serial No. 320,957, filed June 9, 1906, for an improvement in protective apparatus for alternating current elevators.
- the present invention is embodiedin an elevator system and assumes the nature of a protective device therefor in that it automatically opens the main line switch and thus interrupts the current to the motor to eifect the stopping thereof. Furthermore such protective device may be operated by means of a slack cable switch, hatchway limit switches, or by means of a safety switch in the car.
- tors of the multiphase type have from time to time occurred when used in elevator sys tems owing to unexpected change in phase relation of the current either on the lines exterior to the building or to changes in connections in the building.
- One of the means employed as a protection against such accidents or derangement of control has involvedthe principles of the revolving field as made use of in the multiphase induction motor. l/Vindings necessary to produce a revolving magnetic field in a stationary frame when energized with multiphase current, are placed in such relation to a secondary member that a torque is generated between the two members, its direction depending upon the relation between the phases.
- a main circuit switch is held in closed position against the action of gravity or a spring by the above-mentioned device when the relation between the phases is thatfor which the elevator controlling devices have been adjusted. Should the phase relation be reversed, however, the direction of torque in the protecting device would be reversed and the main line switch would be opened.
- the parts of the device are so proportioned that they might remain in stationary condition indefinitely without damage from overheating.
- provision is made to open the main line circuit in the event of phase reversal, with the addition of but small cost to a specific power motor arrangement, and without the consumption of other than a momentary current.
- the motor M On the bed plate B is mounted the motor M having a movable stator frame 1.
- This stator frame is provided with journals 41 mounted in the bearings 2 at the upper ends of the standards 3.
- the journals 1 act as bearings for the rotor shaft 5, rigidly connected in this instance is a downwardly projecting arm 6 which carries the armatures 18, 18 of the holding magnets 17 17.
- the latter act as stops for limiting the rotative movement of the stator frame 1.
- a, b, 0 designate the main lines connecting the source of supply to the switch contacts 23, 24;, 25.
- a, Z), 0 indicate continuations of the main line to the reversing switches R, R.
- the insulating lever 22 which carries the movable contacts of the main line switch, is shown pivoted at 27 and provided with a handle 26. Normally the main line switch L is held in closed position by means of the latch 28 which is pivoted at 29. Rigidly connected with the latch 28 is an arm 30 extending over the tripping electro-magnets 31, 32 and 33 so as to lie in the path of travel of the cores of said electro-magnets.
- the electro-magnets 31 and 33 are connected in the circuits a, 0 respectively, whereas the electro-magnet 32 is connected between the circuit Z) and the auxiliary switches comprising the contacts 39, 42, and 39, ⁇ 22".
- the motor M may be connected to operate hoisting apparatus E which comprises a hoisting drum connected by means of the cable 78 over the sheaves 7 9 and 80 to the car C. If the car switch S is actuated one of the reversing switches R- or ll will be closed and also one of the auxiliary switches connected to the electro-magne: 32. For instance, if the lever 90 is moved onto the contact 89, a circuit will be closed from the lead 0 through wire 91, magnet wire J2, contacts of the automatic machine limit switch 83, wire 96, contact 39, lever 90, wire 97, slack cable switch 88, wire 100, to one of the other leads a, Z1; in this case that designated 5.
- the reversing switch It will thereupon be closed and the stator of the motor M will receive current to rotate the stator frame in one direction or the other, say in a clock-wise direction, to ef fect the release of the brake and the energi- Zation of the holding magnet 17. The rotor will then be free to rotate to operate the hoisting apparatus to move the car upwardly. N ow if the motor has operated in the proper direction, no circuit will be closed through the electro-magnet 32 by the engagement of the contact 22 with the fixed contacts ts't.
- the stator will be thrown by the initial torque in the opposite direction to that in which it would be normally rotated for the predetermined movement of the car switch, and the circuit to the middle tripping coil will be immediately completed, and the three-pole switch at once opened and the elevator motor, hoisting apparatus and car brought to rest.
- the phase relation of the main line current has been reversed and the car switch is moved onto contact 89 as before, the reversing switch ll will be closed and the stator frame 1 moved in an anti-clockwise direction.
- the contacts 462 will then be connected by the movable contact 22 and a circuit will be closed from the lead 0 through the wires lO, 4:6, and 45, contacts a l and 22, wire 4-1, contact 42, bridge piece 43, contact 39, wire 37, coil 32, to the lead 6. It will therefore be seen that the tripper coil 32 will receive current and consequently the arm 30 will be struck by the so as to cause the car to be moved upwardly, core movable within the coil 32, and the latch 28 will therefore release the arm 22 to permit the main line switch L to automatically open.
- the safety apparatus is purposely so designed that it will be necessary to manually close the main line switch L which is usu ally placed on a controller board adjacent the hoisting apparatus. This is for the reason that none of the three above-mentioned circuit closing conditions would obtain under circumstances other than those making an inspection of the elevator machine by the attendant, desirable.
- the series coils 31 and 33 are placed on the two outside circuits of the three-pole switch to open the main line circuit when excessive current flows therethrough, due either to excessive potential or load, defective motor windings, low periodicity, or the blowing of a fuse on any one of the three legs of the circuit thus turning the current supply to the motor from multiphase to single-phase.
- an alternating current induction motor comprising a frame having a limited degree of rotative movement in either direction from its normal or central position, of two electro-magnets, one for holding the frame in one of its limiting positions and the other for holding said frame in the other of its limiting positions, an armature carried by said frame to close the magnetic circuit of either electro-mag net, switch mechanism operated upon movement of said frame to control the energization of said electro-magnets, direction switches for controlling the flow of current through said motor, a main line switch, electro-mechanical tripping appliances for open ing said main line switch automatically, auxiliary switches connected to said direction switches, and additional switch mechanism operated by movement of said frame and co-acting with said auxiliary switches to effect the operation of said tripping appliances when the motor starts in a direction contrary to that selected.
- I11 an elevator system, the combination with a car, hoisting apparatus and multiphase alternating current motor, of reversing switches controlled from the car, two safety switches associated with the motor, one or the other being operated upon a limited revoluble movement of the stator frame, a main line switch, means for holding the last-named switch closed, a tripping electromagnet, and auxiliary switches associated with said reversing switches and co-acting with said safety switches to complete a circuit through said tripping electro-magnet to effect the opening of the main line switch when the relation of phases of the main line current is reversed and the stator frame moved in a direction opposite to that predetermined.
- reversing switch apparatus comprising single-phase electromagnets, a switch in the car for controlling said electro-magnets, means for holding said switch in closed position, a single-phase electromagnet for tripping said holding means to permit the main line switch to open, auxiliary switches associated with said reversing switch apparatus, and safety switches operated by a limited movement of the stator frame and co-acting with said auxiliary switches to complete a circuit through said tripping electro-magnet upon a reversal of phase relation of main line current.
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- Engineering & Computer Science (AREA)
- Automation & Control Theory (AREA)
- Elevator Control (AREA)
Description
W. N. DICKINSON, JR- ANTIPHASE REVERSING DEVICE.
'APrLmu-lon FILED JULY a, 1906.
949,465, Patented Feb. 15, 1910.
wanes M24 N vwemtoz ANDRENIL GRANAM cc. PHOTO-UTMOGRAPKERS, WASHINGTON. n. c.
UNITED sTA Es PATENT oEEioE.
WILLIAM N. DICKINSON, JR., OF NEW YORK, N. Y., ASSIGNOR TO OTIS ELEVATOR COMPANY, OF JERSEY CITY, NEW JERSEY, A CORPORATION OF NEW JERSEY.
ANTIPHASE REVERSING DEVICE.
To all whom it may concern:
Be it known that I, WILLIAM N. DICKIN- SON, J r., a citizen of the United States, residing in New York, borough of Brooklyn, in the State of New York, have invented a new and useful Improvement in Antiphase Reversing Devices, of which the following is a specification.
My invention relates to a safety device for interrupting electric circuits and although it is herein shown applied to motor-control ling circuits of an elevator system, it may have a general application.
The primary object of my invention is the provision of automatic means for interrupt ing the connection between the source of power and a translating device when the latter does not operate as desired.
More particularly it is the object of the present invention to provide means for automatically opening the main line switch connected to an electric motor if the latter does not operate in the desired direction by reason of reversal of current relations on the main line. 2
Another object of my invention is the provision, in an elevator system, of means for ctmtrolling the openingof the main line switch for the motor, from a predetermined point.
Other objects of the present invention will appear hereinafter, the novel combinations of elements being pointed out in the claims.
The accompanying drawing illustrates the principles of my invention and shows the application thereof to an electric elevator system.
The invention is particularly adapted to be used in connection with a torque-release brake such as described in my co-pending application, Serial No. 320,957, filed June 9, 1906, for an improvement in protective apparatus for alternating current elevators.
The present invention is embodiedin an elevator system and assumes the nature of a protective device therefor in that it automatically opens the main line switch and thus interrupts the current to the motor to eifect the stopping thereof. Furthermore such protective device may be operated by means of a slack cable switch, hatchway limit switches, or by means of a safety switch in the car.
Accidents and the derangement of control in connection with alternating current mo- Specification of Letters Patent.
Application filed July 3,1906.
Patented Feb. 15, 1910.
Serial No. 324,541.
tors of the multiphase type, have from time to time occurred when used in elevator sys tems owing to unexpected change in phase relation of the current either on the lines exterior to the building or to changes in connections in the building. One of the means employed as a protection against such accidents or derangement of control has involvedthe principles of the revolving field as made use of in the multiphase induction motor. l/Vindings necessary to produce a revolving magnetic field in a stationary frame when energized with multiphase current, are placed in such relation to a secondary member that a torque is generated between the two members, its direction depending upon the relation between the phases. A main circuit switch is held in closed position against the action of gravity or a spring by the above-mentioned device when the relation between the phases is thatfor which the elevator controlling devices have been adjusted. Should the phase relation be reversed, however, the direction of torque in the protecting device would be reversed and the main line switch would be opened. The parts of the device are so proportioned that they might remain in stationary condition indefinitely without damage from overheating. In the present invention provision is made to open the main line circuit in the event of phase reversal, with the addition of but small cost to a specific power motor arrangement, and without the consumption of other than a momentary current.
On the bed plate B is mounted the motor M having a movable stator frame 1. This stator frame is provided with journals 41 mounted in the bearings 2 at the upper ends of the standards 3. The journals 1 act as bearings for the rotor shaft 5, rigidly connected in this instance is a downwardly projecting arm 6 which carries the armatures 18, 18 of the holding magnets 17 17. The latter act as stops for limiting the rotative movement of the stator frame 1.
As explained in my co-pending application hereinbefore referred to, the armature 18 or 18 engages with the poles of the magnet 17 or 17 to close the magnetic circuit thereof before or substantially at the same time that the contacts 21 supported by the insulating extension 19 engage the fixed contacts 20 or 20. It will be seen that the movable contacts 21 are connected by means of the leads 36 to the motor terminals 35, so that when the contacts 21 engage the fixed contacts 20 or 20 the solenoids of the magnet 17 or 17 will become excited with current and the stator frame held firmly in its limiting position after being moved to either limit of rotative movement by the torque of the motor when starting. Also carried by the insulating extension 19 of the arm 6 is a contact 22 adapted to engage and electrically connect the contacts 4% or 44:. The latter contacts are connected to vauxiliary switches co-acting with the reversing switches, said auxiliary switches being connected to one of the tripping co1ls for operating the releasing device of the main line switch L.
For the purpose of illustration I have shown a simple main line switch and releasing mechanism therefor, but it should be understood that the details thereof may be varied by those skilled in the art without departing fromthe principles of my invention.
a, b, 0 designate the main lines connecting the source of supply to the switch contacts 23, 24;, 25.
a, Z), 0 indicate continuations of the main line to the reversing switches R, R. The insulating lever 22 which carries the movable contacts of the main line switch, is shown pivoted at 27 and provided with a handle 26. Normally the main line switch L is held in closed position by means of the latch 28 which is pivoted at 29. Rigidly connected with the latch 28 is an arm 30 extending over the tripping electro- magnets 31, 32 and 33 so as to lie in the path of travel of the cores of said electro-magnets. The electro- magnets 31 and 33 are connected in the circuits a, 0 respectively, whereas the electro-magnet 32 is connected between the circuit Z) and the auxiliary switches comprising the contacts 39, 42, and 39, {22". Should the main line current increase to a predetermined unsafe value while the motor is in operation, or when one of the reversing switches is closed, either the electro- magi'iet 31 or 33 or both would be operated to effect the actuation of the latch 28 and the consequent release of the arm 22 and the opening of the main line switch L. The current being thus cut off from the motor, any suitable brake provided therefor will be automatically applied and a centering device would bring the arm 6 back to central position as shown in the drawing.
If desired, the motor M may be connected to operate hoisting apparatus E which comprises a hoisting drum connected by means of the cable 78 over the sheaves 7 9 and 80 to the car C. If the car switch S is actuated one of the reversing switches R- or ll will be closed and also one of the auxiliary switches connected to the electro-magne: 32. For instance, if the lever 90 is moved onto the contact 89, a circuit will be closed from the lead 0 through wire 91, magnet wire J2, contacts of the automatic machine limit switch 83, wire 96, contact 39, lever 90, wire 97, slack cable switch 88, wire 100, to one of the other leads a, Z1; in this case that designated 5. The reversing switch It will thereupon be closed and the stator of the motor M will receive current to rotate the stator frame in one direction or the other, say in a clock-wise direction, to ef fect the release of the brake and the energi- Zation of the holding magnet 17. The rotor will then be free to rotate to operate the hoisting apparatus to move the car upwardly. N ow if the motor has operated in the proper direction, no circuit will be closed through the electro-magnet 32 by the engagement of the contact 22 with the fixed contacts ts't. If it is attempted to trace a circuit through the electro-magnet it will be found that the closed auxiliary switch is connected to one of the contacts la, whereas the contacts at engaged by the contact 22 are connected by means of the wire etl to the open contact 42. Itwill therefore be seen that the contacts ist, ist, and the auxiliary switches are so arranged and connected that the circuit to the central tripper coil 32 of the three-pole main line switch is not completed when the stator is rotated in the direction in which it would be normally rotated by the initial torque when the relation between the phases of the line current is that for which the automatic stops have been adjusted, and the car switch connected. If, however, the phase relation of the main line has been reversed, the stator will be thrown by the initial torque in the opposite direction to that in which it would be normally rotated for the predetermined movement of the car switch, and the circuit to the middle tripping coil will be immediately completed, and the three-pole switch at once opened and the elevator motor, hoisting apparatus and car brought to rest. For instance, if the phase relation of the main line current has been reversed and the car switch is moved onto contact 89 as before, the reversing switch ll will be closed and the stator frame 1 moved in an anti-clockwise direction. The contacts 462 will then be connected by the movable contact 22 and a circuit will be closed from the lead 0 through the wires lO, 4:6, and 45, contacts a l and 22, wire 4-1, contact 42, bridge piece 43, contact 39, wire 37, coil 32, to the lead 6. It will therefore be seen that the tripper coil 32 will receive current and consequently the arm 30 will be struck by the so as to cause the car to be moved upwardly, core movable within the coil 32, and the latch 28 will therefore release the arm 22 to permit the main line switch L to automatically open.
As before stated, when the mainline switch is thus opened, the stator frame will return to its normal position and the brake applied to stop the motor and hold the car in station ary position. For the sake of clearness and to prevent confusion, I have not herein shown the centering device or brake apparatus as it is no part of the present inven' tion, such device and apparatus being described and claimed in combination with my co-pending application hereinbefore referred to. It should also be observed that should the car pass beyond the limits of its travel for which the hoisting machine automatics are adjusted, either one or the other of the hoistway limit switches 31 or 82 will be closed by the cam 103 on the car. In such event a circuit through the middle tripping coil 32 will be closed, and consequently the main line switch L opened and the car brought to rest. If the limit switch S1 is closed, a circuit is established from the lead a through the wires 10 and 17 wire 98, switch 81, wire 99, coil 32 to lead Z). It will also be noted that the same object may be accomplished by closing the safety switch 48 in the elevator car itself, and that on the opening of the main line switch L from any cause, it will be impossible to again start the car except by first manually closing said switch L. The circuit closed by the safety switch i8 in the car may be traced from the lead 0 through wires 40 and 50, switch 48, wire 19, wire 99, coil 32 to lead b.
The safety apparatus is purposely so designed that it will be necessary to manually close the main line switch L which is usu ally placed on a controller board adjacent the hoisting apparatus. This is for the reason that none of the three above-mentioned circuit closing conditions would obtain under circumstances other than those making an inspection of the elevator machine by the attendant, desirable. The series coils 31 and 33 are placed on the two outside circuits of the three-pole switch to open the main line circuit when excessive current flows therethrough, due either to excessive potential or load, defective motor windings, low periodicity, or the blowing of a fuse on any one of the three legs of the circuit thus turning the current supply to the motor from multiphase to single-phase.
I have shown my invention in connection with an ordinary multiphase induct-ion motor of the squirrel cage type, but it is also applicable to direct current motors or to any form of alternating current or direct current apparatus in which the action of the brake simultaneously with, or approximately simultaneously with, the application or interruption of power, or current to the motor, is desired. It is obvious that those skilled in the art may make various changes in the details and arrangement of parts of my invention without departing from the principles thereof, and I desire therefore not to be limited to the precise construction herein disclosed.
- Having thus fully described my invention, what I claim and desire to have protected by Letters Patent of the United States is 1. The combination with a motor comprising a frame having a limited revoluble movement, of a main line switch, tripping apparatus therefor, reversing switches, aux" iliary switches cooperating with said reversing switches, and safety switches operated by the revoluble frame of the motor and co acting with said auxiliary switches to effect the operation of the tripping apparatus when the motor turns in a wrong direction.
2. In an elevator system, the combination with a. car, hoisting apparatus and motor, of motor-controlling apparatus, a normally open. safety switch in the car, and means operatedby the closing of said safety switch for cutting of themain line current to the system.
3. The combination with a motor having one partarranged for continuous movement and the other for limited movement, of controlling apparatus therefor, and means dependent upon said other part for effecting a stopping of the motor when the latter starts in the wrong direction.
l. The combination with an electric motor having one member arranged to rotate continuously and the other member to have a limited rotative movement, of an electric switch operated by said other member, and means controlled by said switch to effect the cutting off of current from the motor when the latter starts in a direction contrary to that selected.
5. The combination with a motor having an inner rotative member and an outer member mounted to have a limited degree of rotation, of controlling apparatus for said motor, a switch arranged to be closed upon movement of said outer member, and means controlled by said switch for effecting a stopping of the motor upon the latter starting to rotate in a direction contrary to that selected.
6. The combination with an induction motor having a stator frame mounted for a limited rotative movement, of an arm connected to said frame to move therewith, a circuit-closing member carried by said arm, a plurality of contacts in the path of movement of said circuit-closing member and engaged thereby when said frame rotates, and means controlled by said circuit-closing member and contacts for cutting off current to the motor to stop the same upon the latter starting in a direction contrary to that selected.
7. The combination with an electric motor having a frame mounted for a limited degree of rotative movement, of an electromagnet for holding said frame in its limited position, an armature carried by said frame and movable against said electro-magnet to close its magnetic circuit, a switch closing the electric circuit through said electromagnet when its magnetic circuit is closed, additional switch mechanism operated by movement of said frame, and means controlled by said additional switch mechanism for cutting off current to the motor when the latter starts in a direction contrary to that selected.
8. The combination with an alternating current induction motor comprising a frame having a limited degree of rotative movement in either direction from its normal or central position, of two electro-magnets, one for holding the frame in one of its limiting positions and the other for holding said frame in the other of its limiting positions, an armature carried by said frame to close the magnetic circuit of either electro-mag net, switch mechanism operated upon movement of said frame to control the energization of said electro-magnets, direction switches for controlling the flow of current through said motor, a main line switch, electro-mechanical tripping appliances for open ing said main line switch automatically, auxiliary switches connected to said direction switches, and additional switch mechanism operated by movement of said frame and co-acting with said auxiliary switches to effect the operation of said tripping appliances when the motor starts in a direction contrary to that selected.
2). In an elevator system, the combination with a car, hoisting apparatus and motor, of safety switches operated by a limited movement of the motor frame, a main line switch, electro-magnetic apparatus associated with said main line switch, motorcontrolling means operable from the car, and auxiliary switches cooperating with said motor-controlling means and co-acting with said safety switches to effect the operation of said electro magnetic apparatus to open the main line switch upon the motor starting or tending to start contrary to a predetermined direetion.
10. I11 an elevator system, the combination with a car, hoisting apparatus and multiphase alternating current motor, of reversing switches controlled from the car, two safety switches associated with the motor, one or the other being operated upon a limited revoluble movement of the stator frame, a main line switch, means for holding the last-named switch closed, a tripping electromagnet, and auxiliary switches associated with said reversing switches and co-acting with said safety switches to complete a circuit through said tripping electro-magnet to effect the opening of the main line switch when the relation of phases of the main line current is reversed and the stator frame moved in a direction opposite to that predetermined.
11. In an elevator system, the combination with a car, hoisting apparatus and multiphase alternating current motor, of an arm carried by the revoluble stator frame, an armature carried by said arm, fixed electromagnets in the path of movement of said armature and serving to limit the movement of the stator frame and hold the same in such limiting position in either direction, switch contacts adjacent the electro-magnets, a circuit-closer carried by said arm and engaging one set of such switch contacts when the stator frame is in limiting position, and means co-acting with said circuit-closer and contacts to open the main line upon reversal of phase relation of current and a rotation of the stator frame in a contrary direction.
12. In an elevator system, the combination with a car, hoisting apparatus and multiphase induction motor, reversing switch apparatus comprising single-phase electromagnets, a switch in the car for controlling said electro-magnets, means for holding said switch in closed position, a single-phase electromagnet for tripping said holding means to permit the main line switch to open, auxiliary switches associated with said reversing switch apparatus, and safety switches operated by a limited movement of the stator frame and co-acting with said auxiliary switches to complete a circuit through said tripping electro-magnet upon a reversal of phase relation of main line current.
In testimony whereof, I have signed my name to this specification in the presence of two subscribing witnesses.
IVILLIAM N. DICKINSON, Jn.
IVitnesses CHARLES M. NIssEN, IV. H. BRADY.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US1906324541 US949465A (en) | 1906-07-03 | 1906-07-03 | Antiphase reversing device. |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US1906324541 US949465A (en) | 1906-07-03 | 1906-07-03 | Antiphase reversing device. |
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US949465A true US949465A (en) | 1910-02-15 |
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US1906324541 Expired - Lifetime US949465A (en) | 1906-07-03 | 1906-07-03 | Antiphase reversing device. |
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Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4422029A (en) * | 1981-05-28 | 1983-12-20 | Doorlec Corporation/Corporation Doorlec | Instant reverse control circuit for a single phase motor |
-
1906
- 1906-07-03 US US1906324541 patent/US949465A/en not_active Expired - Lifetime
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4422029A (en) * | 1981-05-28 | 1983-12-20 | Doorlec Corporation/Corporation Doorlec | Instant reverse control circuit for a single phase motor |
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