Патент USA US2411763код для вставки
Nov. 26, 19460' A. w. SWINGLE EI'AL 2,411,763 CONTROL SYSTEM 1 Filed Feb. 2,-- 1944 15b Lon/5pm 851,6 aw _ I /z _‘ lnven'tohsz AP'LTT‘O W.' Swingie, George H. pe‘t‘tibone, Joseph E. Dill, Their‘ Attorney Patented Nov. 26, 1946 2,411,763 UNITED STATES PATENT OFFICE‘ 2,411,783 CONTROL SYSTEM Artro W. Swingle, Schenectady, George H. Petti bone, Scotia, and Joseph E. Dill, Schenectady, N. Y., assignors to General Electric Company, a corporation of New York Application February 2, 1944, Serial No. 520,728 4 Claims. (Cl. 172-—239) This invention relates to control systems, more particularly to systems for controlling the op eration of an electric motor, and it has for an 2 I9 comprises contacts Illa to I9)‘, inclusive, and the group 20 comprises contacts 20a to 20)‘, inclu sive. Both groups of contacts are mounted on a supporting member 2|, with the individual con tacts separated from each other. The member character. 2| is preferably made of a suitable insulating A more specific object of the invention is the material. provision of. a control circuit arrangement which The innermost contacts I91: and 20a of the two minimizes heat losses resulting from circulating currents. 10 groups are connected to the opposite terminals Ilb and I40, respectively, of the speed varying In carrying the invention into e?ect in one form resistor I4, and the contacts lab and 2017 are con thereof, a split series ?eld motor is utilized, to nected together to the terminal I8a of the speed gether with a directional resistor connected across varying resistor l8 and thus to the center tap the terminals of the field winding and a speed controlling resistor connected between an inter 15 Ha of the directional resistor. The taps lab, I80, I8d, and the terminal I88 of the speed varying mediate tap of the directional resistor and one resistor it are connected to the contacts lsc, ISd, side of the source. These resistors are controlled I9e, and I9], respectively, of the group I9, and by banks of spring contacts which in turn are also to corresponding contacts Zilc, 20d, 20c, and selectively actuated by high and low speed Selsyns. In illustrating the invention in one form there 20 20! of the group 20. Capacitors 22 and 23 are connected across the taps I80 and ltd and be of, it is shown as embodied in the drive portion tween midtap I8d and the terminal lie. of a follow-up control system. The actuation of the contacts to control the For a better and more complete understanding speed of the motor I 0 is controlled by a high of the invention, reference should now be had to speed "?ne” Selsyn receiver 24 and by a low the following specification and to the accompany 25 speed or or "c0arse” Selsyn receiver 2!. These ing drawing of which the single ?gure is a simple, Selsyn receivers 24 and 25 are electrically con diagrammatical sketch, partly in perspective, of object the provision of a simple, reliable, im proved, and inexpensive control system of this an embodiment of the invention. nected to high and low speed Selsyn transmitters, respectively, (not shown). The high speed Selsyn Referring now to the drawing, an electric motor III is connected to drive an object H into posi 30 receiver 24 comprises a rotor member 24a and a stator member 241) which, in this application, is tional agreement with a remote controlling object mounted in ball bearings and is free to rotate. It (not shown). is connected through spur gearing 28 and worm The motor III is a split series ?eld type motor; gearing 28a to the shaft of the drive motor I II. ‘ i. e., its ?eld winding is divided into two ?eld coils Ilia and Ilb of opposite polarity to e?ect rotation 35 The ratio of the gearing is such that the ratio be tween the revolutions of the stator 24b and the of the motor in either direction when the excita driven object I I is a suitable number such as 36:1; tion of one ?eld coil predominates over that of i.‘ e., the stator 2417 will rotate 36 times for each the other. The lower brush Iiic of the motor is revolution of the driven object I I. connected to one side I 2 of an A.-C. supply source I2, H. The upper brush I M of the motor is con 40 The low speed Selsyn receiver 25 has a rotor member 25a and a rotatably mounted stator mem nected to the common point of the two ?eld coils ber 26b. The rotatably mounted stator 24!: of the Ito and llib. high speed Selsyn receiver is connected with the A resistor I4 and a capacitor I! are connected rotatably mounted stator 25b of the low speed in parallel across the opposite terminals of the ?eld coils Ilia and “lb by means of conductors 45 receiver by means of gearing 21 having a ratio such that the low speed stator 25?) rotates at a l8 and II. This resistor is referred to as the very low speed with respect to stator 24b; e. g., directional control resistor. A second resistor II one revolution for each 36 revolutions of the high is connected between the center tap Ha of re speed stator 24b. sistor I4 and the side I2 of the A.-C. supply source. This resistor is provided with a plurality of taps 60 For directly actuating the contacts of'the banks It and 20, a member 28:: located in the space Ito, I8b, lie, Ild, and I88 to provide for short between the two banks and mounted on a lever cireuiting portions of the resistor, thereby to vary 28 is provided. The lever 28 is mounted in a suit the speed of the motor I0. Consequently, re able bearing 29 for rotation about the bearing sistor I 8 is referred to as the speed varying re Y axis. Rotation of the lever 28 is effected by means sistor. 55 of a heart cam assembly comprising a heart To provide for short circuiting the portions of shaped cam 30 which is secured to the shaft of the resistor which are de?ned by the taps "a to rotor 24a and a cam follower 2| mounted on a lie, inclusive, a plurality of spring contacts are yoke 22 which is pivotally connected to lever 28. provided. These contacts are arranged in two To provide for transferring the control of the groups or banks It and 20. As shown, the group 60 contacts from the high speed Selsyn receiver to aria-tee 3 the low speed Selsyn receiver under certain oh erating conditions; i. e., when the positional dis agreement of the transmitters and receivers ex '> it the rotor 26a will rotate the heart cam do in a counterclockwise direction, thereby to move the member 26a downward. The downward move ment of member 28a relieves the pressure on the ceeds a predetermined amount, the lever 28 is provided with an armature 33 which is attracted contacts of bank it, thereby successively insert ing the sections of the speed controlling resistor in one direction or the other by means of two electromagnets 3d and 35. The selective ener i t in the armature circuit and reducing the speed gization of the operating coils 3M and 35a of these of motor it. The separation of contacts the and electromagnets is controlled by means of a heart lab interrupts the short circuit about the upper cam assembly 36 which is operated by the low ill half of the directional resistor it. This results speed receiver 25, together with a pair of'direc in reducing theexcitation of the split field coil tional contacts 31 and 38. Ida to equalize the excitation of both split ?eld The operation is as follows: At any instant cur‘ coils ltd. and, iEb and restore the standby zero rents ?ow from one side of the source through torque condition of the motor ill. the armature ID of the follow-up motor, ?eld 15 The rotors'25a and ‘25b rotate simultaneously coils Ida and lob in parallel, upper and lower with the rotor 26a and stator 2th and in the same halves of the directional control resistor ill in > directions, respectively. Owing to the 36:1 reduc parallel to the center tap Ma, speed varying re tion of gearing 27, the amount of rotation of the sistor it to the opposite side of the source. Since rotor 25a and the stator 25b is only one-thirty the upper and lower halves of the directional 20 sixth the corresponding rotations "of the rotor control resistor it are equal, the currents cir 24a and the stator 24b of the high speed Selsyn culating through these halves to the ?eld wind ing coils Ma and liib are also equal. Con If the rotation of rotor 25a in a clockwise di sequently, the torques produced by these currents rection exceeds a predetermined amount, e. g., receiver. ' ’ l a ' are opposite so that the net torque acting on the 25 two and one-half degrees, the heart cam 30 will armature I0 is zero and the motor is at rest. have rotated to the 90-degree position, at which When the motor is at rest, the circulating cur position it is desirable to transfer control to the rents are reduced to a very low value, owing to low speed Selsyn 25. The rotation of the heart the high ohmic resistance of the directional re cam assembly 36 closes contacts 37, thereby to en sistor, and thus the standby losses of the motor 30 ergize operating coil Ma. The armature 33 is at are reduced to a minimum. tracted toward core member 36, thereby rotating lever 28 in a clockwise direction to close all the contacts of bank is which may not have been the rotors of the transmitters. If the rotation closed by rotation of rotor ‘Eda. The speed of of the rotor 29a is in a clockwise direction, the 35 ‘motor i0 is rapidly accelerated to its maximum cam follower ill will have a component of move value. As a result, the driven object ii is driven ment toward the right, thereby to rotate the in the desired direction at maximum speed and Rotation of the rotors of the transmitters causes the rotors-Eda and 25a to rotate to follow lever 28 in a clockwise direction about the axis the stators 26b and 251) are driven in a counter—. of bearing 29. The clockwise rotation of lever clockwise direction. When the counterclockwise 28 moves the member 280. into engagement with 40 speed of the stators exceeds the speeds of the contact i9q. As the clockwise rotation of the rotors of the transmitters to which they are re rotor 23a continues; contact i9a is moved into spectively connected, the rotors 255a and 25a will engagement with contact lsb, thereby short cir rotate in a counterclockwise direction. When cuiting the half of the directional control re-p the rotor 25a returns to within two and one-half sistor it between the center tap Ma and the ter degrees of its initial position with respect to the minal lfib. As a result, more current ?ows rotor of the low speed transmitter, the heart through the split ?eld coil iila than ?ows through _ ' cam assembly 36 will open the contacts 37, there coil I?b, and a net torque is developed which by to deenergize the operating coil Sta. As a re causes the motor ill to rotate in a direction which sult of the deenergization of coil Sta, the arma drives the stator 24b in a counterclockwise direc 50 ture 33 is no longer attracted by the core member tion. Owing to the full amount of resistor l8 in ‘34 and, consequently, the control of the contacts the armature circuit of the motor, the rotation I9a to WI, inclusive, is restored to the high speed is at a slow speed. The rotor 24b continues to Selsyn 26. rotate in the clockwise direction and at a speed If the initial rotation of the rotor Eda is in a which is equal to the di?erence between the speed 55 counterclockwise direction, in response to a ro of the transmitter rotor and the speed of the tation of the rotor of the transmitter in a di stator 26b. A continued clockwise rotation of rection opposite to that described in the fore the rotor 24a acting on the heart cam assembly going, the operation will be the same as that de causes the member 28a to continue its upward scribed except that the rotation of the heart cam movement to close the contacts I90, i901, lee, and 80 30 and lever 28 will be in a counterclockwise di lQf in succession. With the successive closing of rection and the contacts 20a to 20f, inclusive, of the lower bank 20 will be actuated. The closing these contacts, successive sections of the speed varying resistor l8 are short circuited, thereby of contacts 2M and 28b short circuits the lower increasing the voltage applied across the arma half of the directional resistor I ti, thereby e?ect ture and ?eld coil Ilia. As a result, the speed of 65 ing rotation of the motor ii! in the reverse di~ the motor Ill increases until the speed of the rection. The subsequent successive closing of _ counterclockwise rotation of the stator ‘25b is contacts 201), 20c, 29d, we, and 20)‘ short circuits equal to the speed of the rotor of the transmitter. successive portions of the speed varying resistor E8 to accelerate the motor H3 in the manner de When this condition is reached, the rotor Zea is at scribed in the foregoing. standstill with the result that the speed of the Although in accordance with the provisions of motor i0 is not further increased. the patent statutes, this invention is described If, now, the speed of the transmitter is de as embodied in concrete form and the principle creased, the speed of the stator 24b does not de thereof has been explained, together with the crease at ‘?rst because it cannot change until the speed of motor ill changes. Consequently, 75 best mode in which it is now contemplated apply 2,411,763 ing that principle, it will be understood that the apparatus shown and described is merely illus trative and that the invention is not limited thereto, since alterations and modi?cations will readily suggest themselves to persons skilled in the art without departing from the true spirit of this invention or from the scope of the an nexed claims. What we claim as new'and desire to secure 6 disposed space, each of said banks comprising a plurality of spring contacts mounted in spaced apart relationship, a contact of one of said banks being connected to one terminal of said ?rst re= sistor and a corresponding contact of the other bank being connected to the opposite terminal oi said ?rst resistor and each of the taps of said sec~ 0nd resistor being connected to a different one oi.’ the contacts of one of said banks and a corre by Letters Patent of the United States is: 10 sponding contact of the second bank, an actuat 1. A control system comprising in combination, ing member mounted in said centrally disposed a split series ?eld motor having one armature space for movement in opposite direction, a rela terminal connected to an intermediate tap of tively high speed Selsyn receiver for moving said the series ?eld winding and a connection from member in a selected direction to initiate the the opposite armature terminal leading to one 15 successive closing of the contacts of the selected side of a supply source, a resistor connected across bank thereby to short circuit a selected portion said series ?elding winding, a second resistor of said ?rst resistor to effect rotation of said connected-from an intermediate tap of said ?rst motor in a selected direction and to increase its resistor to the opposite side of said source and speed, a relatively low speed Selsyn receiver, speed having a plurality of taps, a plurality of spaced apart contacts arranged in two banks, a contactv 20 reducing gearing connecting said Selsyns, and means responsive to a predetermined amount of of one of said banks being connected to one ter rotation of said low speed Selsyn receiver for mov minal of said ?rst resistor and ‘a corresponding ing said actuating member to an extreme position contact of the other bank being connectedto the to close all of said contacts 01' said selected bank opposite terminal of said ?rst resistor and each thereby to effect rotation of said motor at maxi of the taps of said second resistor being connected to a different one o1r the contacts of one bank and to a corresponding contact of the second bank, and means for selectively engaging the contacts mum speed. 4. A control system comprising in combination, a split series ?eld motor having one armature terminal connected to an intermediate tap of the of one of said banks to close in succession there by to short circuit a selected portion of said ?rst 30 series ?eld winding and a connection from the resistor to effect rotation of said motor in ‘a, cor opposite armature terminal to one side of a sup responding direction and successively to short ply source, a resistor connected across said series circuit portions of said second resistor to vary ?eld winding, a second resistor connected from an intermediate tap of said ?rst resistor to the opposite side of said source and having a plu rality of taps, a pair of banks of spring contacts separated from each other to provide a centrally disposed space, each of said banks comprising a the speed of said motor. , ‘ I 2. A control ‘system comprising in combination, a split series ?eld motor having one armature terminal connected to an intermediate tap of the series ?eld winding anda connection from, the opposite armature terminal to one side of a plurality of spring contacts mounted in spaced supply source, a ?rst resistor connected across said series ?eld winding, a second resistor con apart relationship, a contact of one of said banks being connected to one terminal of said ?rst re sistor and a corresponding contact of the other nected from the midpoint of said ?rst resistor to the other side of, said source and having a bank being connected to the opposite terminal of plurality of taps, a supporting member, a plural 45 said ?rst resistor and each of the taps of said sec ity of contacts mounted on said supporting mem ond resistor being connected to a di?erent one of ber in cooperative spaced apart relationship and the contacts of one of said banks and a correin two groups separated from each other to pro sponding contact of the second bank, a pivotally vide a centrally. disposed space,~the_end contacts mounted lever provided with an actuating menu of said groups adjacent said centrally disposed ber in said, centrally disposed space and also pro spacebeing connected to opposite terminals of 50 vided with an armature member, a pair of op said ?rst resistor, and a member mounted with-7 _ posltely disposed electromagnets arranged in co in said space for movement in opposite direc operative relationship with said armature for ei tions to selectively actuate said groups of con fecting pivotal movement of said lever in opposite tacts and to close the contacts of the selected group in succession thereby to short circuit a se lected half of said ?rst resistor to e?ect rotation of said motor in a selected direction and succes sively to short circuit'portions of said second resistor to vary the speed of said motor. 3. A control system comprising in combination, a split series ?eld motor having one armature terminal connected to an intermediate tap of the series ?eld winding and a connection from the opposite armature terminal to one side of a sup ply source, a resistor connected across said series ?eld winding, a second resistor connected from an intermediate tap of said first resistor to the op posite side of said source and having a plurality of taps, a pair of banks of spring contacts sep arated from each other to provide a centrally directions, a relatively high speed Selsyn receiver for moving said lever in a selected direction to initiate successive closing of the contacts of one of said banks thereby to short circuit a por tion of said ?rst resistor to effect rotation of said motor in a selected direction, a relatively low speed Selsyn receiver, speed reducing gearing connecting said Selsyn receivers, and means re sponsive to a predetermined amount of rota tion of said low speed Selsyn receiver for selec tively energizing said electromagnets to move said lever to an extreme position to close all of said contacts of said selected bank to e?ect ro- ' tation of said motor at maximum speed. ARTRO W. SWINGLE. GEORGE H. PETTIBQNE. JOSEPH E. DILL.