US3329247A - Electromagnetic coupling apparatus - Google Patents

Electromagnetic coupling apparatus Download PDF

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Publication number
US3329247A
US3329247A US493396A US49339665A US3329247A US 3329247 A US3329247 A US 3329247A US 493396 A US493396 A US 493396A US 49339665 A US49339665 A US 49339665A US 3329247 A US3329247 A US 3329247A
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United States
Prior art keywords
voltage
coil
level
torque
energized
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US493396A
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English (en)
Inventor
Ralph L Jaeschke
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Eaton Corp
Original Assignee
Eaton Yale and Towne Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Eaton Yale and Towne Inc filed Critical Eaton Yale and Towne Inc
Priority to US493396A priority Critical patent/US3329247A/en
Priority to GB40620/66A priority patent/GB1131266A/en
Priority to BR182985/66A priority patent/BR6682985D0/pt
Priority to ES0331806A priority patent/ES331806A1/es
Priority to DE19661538789 priority patent/DE1538789C/de
Priority to CH1453266A priority patent/CH459680A/de
Priority to FR78846A priority patent/FR1501095A/fr
Application granted granted Critical
Publication of US3329247A publication Critical patent/US3329247A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
    • H02P29/00—Arrangements for regulating or controlling electric motors, appropriate for both AC and DC motors
    • H02P29/0016—Control of angular speed of one shaft without controlling the prime mover
    • H02P29/0022—Controlling a brake between the prime mover and the load
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
    • F16D67/00—Combinations of couplings and brakes; Combinations of clutches and brakes
    • F16D67/02—Clutch-brake combinations
    • F16D67/06—Clutch-brake combinations electromagnetically actuated
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F7/00—Magnets
    • H01F7/06—Electromagnets; Actuators including electromagnets
    • H01F7/08—Electromagnets; Actuators including electromagnets with armatures
    • H01F7/18—Circuit arrangements for obtaining desired operating characteristics, e.g. for slow operation, for sequential energisation of windings, for high-speed energisation of windings
    • H01F7/1805—Circuit arrangements for holding the operation of electromagnets or for holding the armature in attracted position with reduced energising current
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02K—DYNAMO-ELECTRIC MACHINES
    • H02K49/00—Dynamo-electric clutches; Dynamo-electric brakes
    • H—ELECTRICITY
    • H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
    • H02P—CONTROL OR REGULATION OF ELECTRIC MOTORS, ELECTRIC GENERATORS OR DYNAMO-ELECTRIC CONVERTERS; CONTROLLING TRANSFORMERS, REACTORS OR CHOKE COILS
    • H02P29/00—Arrangements for regulating or controlling electric motors, appropriate for both AC and DC motors
    • H02P29/0016—Control of angular speed of one shaft without controlling the prime mover

Definitions

  • the present invention relates to electromagnetic coupling apparatus and more particularly to such apparatus which provides a rapid buildup of torque transmitted between relatively rotatable members of a coupling.
  • the invention is applicable to electromagnetic coupling apparatus having a pair of relatively rotatable members and a field coil, the energization of which controls the transmission of torque between the two members.
  • the coil is energized to obtain a rapid buildup of a given torque between said members by a control including a voltage multiplier which develops a voltage of a first level under no-load conditions and which under the sustained load of said coil drops to a second level of voltage substantially lower than this first level.
  • the second voltage level is one which is sufiicient to maintain the coil energized for the steady state transmission of the given torque.
  • the coil is selectively connected by a switching device or means to a voltage multiplier.
  • the multiplier includes means for storing energy at said first voltage level when disconnected from the coil.
  • electromagnetic coupling apparatus includes apparatus wherein torque is controllably transmitted between a pair of relatively rotatable members whether it is either or both of the members which rotate. Examples of such apparatus are clutches, brakes and dynamometers.
  • FIG. 1 is a diagrammatic illustration of an electromagnetic coupling apparatus of the present invention
  • FIG. 2 is a schematic diagram of circuitry for controlling the operation of the apparatus of FIG. 1 including means for providing accelerated actuation of the clutch and brake;
  • FIG. 3 is a schematic diagram of modified control circuitry providing accelerated actuation of the brake alone
  • FIG. 4 is a schematic diagram of a modification wherein the clutch is energized at a lower voltage level than either the initial or sustained energization level of the brake;
  • FIG. 5 is a schematic diagram of a circuit for controlling operation of an electromagnetic brake to provide extreme decelerations.
  • FIG. 6 is a schematic diagram of another embodiment of this invention.
  • the electromagnetic coupling apparatus comprises both a clutch 11 and a brake 13 which are preferably of the friction type and are arranged for controlling the speed of rotation of a driven shaft 15, taking rotational energy from a motor 17.
  • the shaft of motor 17 is connected to a clutch driving 7 member which in the present case is illustrated as a rotating electromagnet assembly 19 including a field coil or winding 21.
  • Current is supplied to the coil 21 through suitable slip rings (not shown).
  • a disc-like armature 23 is mounted on the output or driven shaft 15 for rotation therewith. Armature 23 is positioned within the field of electromagnet assembly 19 so that when the coil 21 is energized armature 23 will be drawn into frictional engagement with driving member 19.
  • torque may be selectively transmitted between the members 19 and 23 by controlling the energization of coil 21.
  • the brake 13 is similar in construction to clutch 11 and includes an armature 24 and an electromagnet 25 wound with a field coil or winding 27.
  • the electromagnetic structure is stationary and does not rotate, being attached to the frame or other stationary reference point as at 29.
  • winding 27 When winding 27 is energized, the armature 24 is drawn into frictional engagement with the electromagnet 25' so that a braking torque is exerted between electromagnet 25 and the shaft 15.
  • FIG. 2 illustrates a control circuit according to the invention which provides accelerated energization of both the clutch and the brake coils 21 and 27, respectively.
  • the clutch and brake coils are energized by separate power supplies each of which includes a voltage multiplier constituted by a voltage-doubling rectifier circuit drawing power from an A.C. power source represented by a pair of A.C. supply lines L1 and L2.
  • the brake power supply includes a pair of rectifiers or diodes D1 and D2 which are connected to supply line L1 and are oppositely poled or oriented so that each provides half-wave rectified or pulsating D.C. to one of a pair of filter and storage capacitors C1 and C2. One terminal of each capacitor is commonly connected to line L2.
  • this circuit functions as a voltage doubler, the voltage produced under no-load conditions across capacitors Cl and C2 together, or in series, being approximately double the peak supply voltage.
  • the brake coil 27 is selectively connected across capacitors C1 and C2 by a set of contacts 81A of a switch S1 which may, for example, be an electromagnetically operated relay.
  • the clutch coil power supply includes a similar voltage doubler wherein a pair of capacitors C3 and C4 are alternately charged to opposite potentials with respect to supply line L2 through a pair of oppositely poled diodes D3 and D4 connected to line L1.
  • the clutch coil 21 is selectively connected across the series-connected capacitors C3 and C4 by means of a pair of contacts 81B of switch S1.
  • the voltage regulation characteristics of voltage multiplier circuits are typically quite poor in the sense that the voltage provided under loading is significantly lower than that provided under no-load conditions.
  • the regulation characteristics depend to a large extent on the value of the capacitors used.
  • the ratings of the clutch and brake coils 21 and 27 are chosen so that the voltage required for full, steady state energization thereof is substantially below the peak voltage provided by the respective voltage-doubling power supplies. For example, in apparatus supplied from A.C. mains providing A.C.
  • the voltagedoubling power supply for the clutch coil 21 will, under no-load conditions, charge the capacitance constituted by series-connected capacitors C3 and C4 to a total voltage of substantially 300 volts.
  • the clutch coil 21 may, for example, have a continuous energization rating of about 50 volts.
  • the values of the capacitors C3 and C4 are then chosen so that the voltage supplied by the doubler circuit to the clutch coil under conditions of continuous energization is approximately 5.0 volts, a level which will permit the clutch coupling to continuously maintain the rated torque transfer between the relatively rotatable components thereof.
  • the stored energy will provide overexcitation for only a relatively short time and thus, after a predictable delay interval, the voltage provided by the doubler circuit will drop or sag to the level which the doubler is capable of supplying under steady state load conditions.
  • This level is, as noted previously, selected by choice of value for capacitors C3 and C4 to be substantially equal to the rated voltage of the clutch winding 21.
  • the capacitors C1 and C2 are chosen to provide a steady state voltage which is equal to the sustained energization rating of brake winding 27.
  • these capacitors will be charged to a voltage which is substantially double the peak voltage supplied by the lines L1 and L2.
  • the brake coil will be initially overexcited, thereby providing an accelerated braking operation.
  • coil 27 will subsequently be maintained energized by a voltage substantially equal to its sustained energization rating.
  • the brake coil 27 is again connectable across the output of the voltage doubler comprising diodes D1 and D2 and capacitors C1 and C2.
  • the clutch coil 21, however, is not provided with a separate voltage doubler power supply but rather is connectable, through contacts SIB, across one (C2) of the two capacitors used in the brake coil power supply.
  • clutch winding 21 is provided only with half-wave rectified power and does not draw from any voltage doubler or multiplier circuit.
  • clutch coil 21 is chosen to have a sustained voltage rating approximately equal to the value of the half-wave rectified A.C. provided by lines L1 and L2 and rectifier D2.
  • the control of FIG. 3 thus provides essentially normal operation of clutch coil 21 but will, due to the voltage drop characteristics of the doubler power supply, pro vide an initial overexcitation of brake winding 27 so that rapid decelerations of shaft 15 may be obtained.
  • the ratio of peak to full-load voltages will not be as great as that obtained using the circuitry of FIG. 2.
  • FIG. 4 Another arrangement wherein only one of the coupling coils is initially overexcited is illustrated in FIG. 4.
  • the brake winding 27 is selectively connectable by means of contacts 81A to the voltage doubler power supply comprising diodes D1 and D2 and capacitors C1 and C2, the doubler power supply again being supplied from lines L1 and L2 with line L1 providing A.C. power at a first voltage level with respect to line L2.
  • the clutch winding 21 is connected to receive halfwave rectified power through a diode D5 and switch contacts S1B from a supply line L1A which provides A.C. power at a second preselected level with respect to line L2.
  • the peak voltage present at line L1A with respect to line L2 is chosen to the less than either the initial voltage at which the coil 27 is overexcited or the lower voltage level at which its energization is maintained.
  • the brake winding will be initially overexcited to provide rapid stops of the shaft 15 as in the previous examples but energization of the clutch coil 21 will take place at one voltage level only, which voltage level is lower than both the initial and sustained voltage levels applied to winding 27.
  • the potential difference between L1A and L2 may be selected to be equal to or greater than the L1-L2 voltage.
  • Voltage multipliers which treble, quadruple, etc. the supply voltage typically have even poorer voltage regulation characteristics than doublers. In other words, larger ratios of no-load voltage to full-load voltage are en counted. Accordingly, by employing circuits using even higher degrees of voltage multiplication in controls according to the present invention, even more rapid accelerations may be obtained.
  • the brake winding 27 is energized from a voltage quadrupler power supply which comprises a series string of diodes D6-D9.
  • a plurality of capacitors C6-C9 couple A.C. to each of the rectifiers in the string from the lines L1 and L2.
  • this supply will develop a voltage which is substantially equal to four times the peak voltage appearing across the supply lines L1 and L2.
  • the capacitors C6 C9 will be charged and will thus represent a quantity of stored energy avialable for intially overexciting winding 27 at the higher voltage upon its initial connection to the supply.
  • the voltage applied to the winding will drop to a much lower value, the level of which is in large part determined by the individual capacity values of the capacitors C6-C9.
  • the steady state voltage provided by the supply may be made approximately equal to the rated voltage of the coil 27 even though this value is very small in relation to the peak voltage initially provided by the quadrupler supply.
  • control of FIG. 5 is capable of providing a very high degree of initial overexcitation for extremely rapid operation of the brake. It should be understood that a clutch coil could be similarly operated and that both a clutch and brake may be alternately operated in this manner from separate voltage multiplier supplies in the manner illustrated in FIG. 2.
  • FIG. 6 illustrates a control which is similar to that shown in FIG. 5.
  • the voltage multiplier which supplies power to winding 27 is again a quadrupler which includes diodes D6-D9 connected in a series string.
  • a set of capacitors C11C14 couples A.C. to each of the rectifiers.
  • A.C. is coupled to the higher voltage rectifier stages by capacitors which draw power from the lower voltage stages rather than directly from the lines L1 and L2.
  • the series-connected capacitors act as A.C. voltage dividers which cause an even greater drop in the output voltage.
  • this multiplier circuit permits an increased ratio of initial excitation voltage to sustained energization voltage.
  • a voltage multiplier which develops a voltage of a first level under no-load conditions and which under the sustained load of said coil drops to a second level of voltage substantially lower than said first level, said second voltage level being sufiicient to maintain said coil energized for the steady state transmission of said given torque;
  • switching means for selectively connecting said coil to said voltage multiplier, said multiplier including means for storing energy at said first voltage level when said coil is disconnected therefrom whereby, upon connection of the coil to said multiplier, said coil is initially overexcited by being energized at said first voltage level thereby to rapidly build up said given torque and, after discharging of stored energy, said coil continues to be energized at said second voltage level to maintain the transmission of said given torque.
  • Electromagnetic coupling apparatus providing rapid buildup of a given transmitted torque, said apparatus comprising:
  • an electrically controllable coupling including a pair of relatively rotatable members and a field coil the energization of which controls the transmission of torque between the two members;
  • a voltage multiplying rectifier circuit for providing DC. power for energizing said coil from an A.C. power source, said rectifier circuit including a capacitance and being operative when said coil is disconnected therefrom to charge said capacitance to a first voltage which is substantially higher than the steady state voltage which said circuit can maintain across said coil, said steady state voltage bein-g sufiicient to maintain said coil energized for the transmission of said given torque;
  • switching means for selectively connecting said coil to said rectifier circuit whereby, upon connection of the coil to said circuit, said coil is initially overexcited by being energized at said first voltage level thereby to rapidly build up torque and, after discharging of energy stored in said capacitance, said coil continues to be energized at said steady state voltage to maintain the transmission of said given torque.
  • said capacitance comprises at least two capacitors and said rectifier circuit includes at least two rectifiers through which said capacitors are alternately charged.
  • first and second capacitors constituting said capacitance, one terminal of each of said capacitors being commonly connected to one side of said A.C. source;
  • first and second rectifiers each of which connects the other terminal of a respective one of said capacitors to the other side of said A.C. source, said rectifiers being oppositely oriented whereby said capacitors are charged to voltages of opposing polarities with respect to said oneside of said source, said switching means being operative to connect said coil across said two capacitors in series.
  • said electrically controllable coupling includes a third relatively rotatable member and a second field coil the energization of which controls the transmission of torque between said third member and one of the other members and wherein said switching means includes means for selectively connecting said second coil across one of said two capacitors.
  • said electrically controllable coupling includes a third relatively rotatable member and a second field coil the energization of which controls the transmission of torque between said third member and one of the other said members, and wherein said apparatus includes a second voltage multiplying rectifier circuit for energizing said second coil, and wherein said switching means includes means for selectively connecting said second coil to said second rectifier circuit for energization alternately with the first said coil.
  • said electrically controllable coupling includes a third relatively rotatable member and a second field coil the energization of which controls the transmission of torque between said third member and one of the other members and wherein said apparatus includes means for selectively energizing said second field coil at a voltage which differs from said first voltage.
  • said voltage multiplying rectifier circuit includes a plurality 25 of rectifiers poled in the same direction and connected in a series string and a plurality of capacitors for coupling A.C. along said string.

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  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Power Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Hydraulic Clutches, Magnetic Clutches, Fluid Clutches, And Fluid Joints (AREA)
  • Ignition Installations For Internal Combustion Engines (AREA)
US493396A 1965-10-06 1965-10-06 Electromagnetic coupling apparatus Expired - Lifetime US3329247A (en)

Priority Applications (7)

Application Number Priority Date Filing Date Title
US493396A US3329247A (en) 1965-10-06 1965-10-06 Electromagnetic coupling apparatus
GB40620/66A GB1131266A (en) 1965-10-06 1966-09-12 Electromagnetic coupling apparatus
BR182985/66A BR6682985D0 (pt) 1965-10-06 1966-09-20 Um aparelho de acoplamento eletromagnetico e processo de excitar a bobina de campo do mesmo
ES0331806A ES331806A1 (es) 1965-10-06 1966-09-30 Aparato de acoplamiento electromagnetico.
DE19661538789 DE1538789C (de) 1965-10-06 1966-10-01 Steuervorrichtung fur eine elektromag netische Antriebs und/oder Bremskupplung
CH1453266A CH459680A (de) 1965-10-06 1966-10-03 Steuervorrichtung für eine elektromagnetische Kupplung
FR78846A FR1501095A (fr) 1965-10-06 1966-10-05 Dispositif de couplage électromagnétique

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US493396A US3329247A (en) 1965-10-06 1965-10-06 Electromagnetic coupling apparatus

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US3329247A true US3329247A (en) 1967-07-04

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US493396A Expired - Lifetime US3329247A (en) 1965-10-06 1965-10-06 Electromagnetic coupling apparatus

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US (1) US3329247A (de)
BR (1) BR6682985D0 (de)
CH (1) CH459680A (de)
ES (1) ES331806A1 (de)
FR (1) FR1501095A (de)
GB (1) GB1131266A (de)

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3465231A (en) * 1967-12-26 1969-09-02 Varo Transformerless converter-inverter
US3521144A (en) * 1966-09-16 1970-07-21 Philip Martin Voltage multiplier having metallic foil capacitors
US3687250A (en) * 1970-08-03 1972-08-29 Robert C James Auger filler and control therefor
US3735238A (en) * 1971-09-17 1973-05-22 Gen Radio Co Process and apparatus for providing image brightness over a wide range of discharge repetition rates
US4016476A (en) * 1972-09-20 1977-04-05 Citizen Watch Co., Ltd. Booster circuits
US4176735A (en) * 1974-10-14 1979-12-04 Cousin Freres S.A. High-speed apparatus for off-winding thread
US5226860A (en) * 1991-12-31 1993-07-13 Dana Corporation Vehicle torque transfer case
US5533425A (en) * 1992-03-05 1996-07-09 Easom Engineering And Manufacturing Corporation Electrically actuated disc stack having low response time due to reduced residual magnetism for use in drives, brakes and combinations thereof
US5603395A (en) * 1992-03-05 1997-02-18 Easom Engineering & Mfg. Corp. Electrically actuated disc stack having low response time due to reduced residual magnetism for use in drives, brakes and combinations thereof

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2745997A1 (de) * 1977-10-13 1979-04-19 Sew Eurodrive Gmbh & Co Anordnung zum steuern des ein- und ausschaltverhaltens von induktivitaeten, wie elektromagneten o.dgl.
FI66701C (fi) * 1981-08-18 1984-11-12 Karjalainen Vaino Kopplingsfoerfarande
FR2529029B1 (fr) * 1982-06-16 1985-09-06 Centre Nat Rech Scient Moteur lineaire pour le deplacement d'une charge le long d'une trajectoire

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2811686A (en) * 1954-06-01 1957-10-29 Librascope Inc Voltage control system
US2888629A (en) * 1954-02-25 1959-05-26 Research Corp Voltage multiplier
US3254746A (en) * 1965-04-12 1966-06-07 Warner Electric Brake & Clutch Clutch for electric motors
US3268045A (en) * 1964-04-13 1966-08-23 Potter Instrument Co Inc Clutch drive circuit

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2888629A (en) * 1954-02-25 1959-05-26 Research Corp Voltage multiplier
US2811686A (en) * 1954-06-01 1957-10-29 Librascope Inc Voltage control system
US3268045A (en) * 1964-04-13 1966-08-23 Potter Instrument Co Inc Clutch drive circuit
US3254746A (en) * 1965-04-12 1966-06-07 Warner Electric Brake & Clutch Clutch for electric motors

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3521144A (en) * 1966-09-16 1970-07-21 Philip Martin Voltage multiplier having metallic foil capacitors
US3465231A (en) * 1967-12-26 1969-09-02 Varo Transformerless converter-inverter
US3687250A (en) * 1970-08-03 1972-08-29 Robert C James Auger filler and control therefor
US3735238A (en) * 1971-09-17 1973-05-22 Gen Radio Co Process and apparatus for providing image brightness over a wide range of discharge repetition rates
US4016476A (en) * 1972-09-20 1977-04-05 Citizen Watch Co., Ltd. Booster circuits
US4176735A (en) * 1974-10-14 1979-12-04 Cousin Freres S.A. High-speed apparatus for off-winding thread
US5226860A (en) * 1991-12-31 1993-07-13 Dana Corporation Vehicle torque transfer case
US5533425A (en) * 1992-03-05 1996-07-09 Easom Engineering And Manufacturing Corporation Electrically actuated disc stack having low response time due to reduced residual magnetism for use in drives, brakes and combinations thereof
US5603395A (en) * 1992-03-05 1997-02-18 Easom Engineering & Mfg. Corp. Electrically actuated disc stack having low response time due to reduced residual magnetism for use in drives, brakes and combinations thereof

Also Published As

Publication number Publication date
GB1131266A (en) 1968-10-23
FR1501095A (fr) 1967-11-10
BR6682985D0 (pt) 1973-01-11
DE1538789A1 (de) 1970-02-19
CH459680A (de) 1968-07-15
ES331806A1 (es) 1967-11-01
DE1538789B2 (de) 1972-10-26

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