US1980736A - Electroresponsive device and apparatus - Google Patents

Description

1934- L. A. TROFIMOV 1,980,736

ELEGTRORESPONSIVE DEVICE AND APPARATUS Filed April 19, 1928 INVENTOR .Patented Nov. 13, g 1934 1,980,736

UNITED STATES PATENT OFFICE ELECTROBIE SPONSIVE DEVICE AND APPARATUS Lev A. Trofimov, Cleveland, Ohio, assignor to The Electric Controller 86 Manufacturing Company, Cleveland, Ohio, a corporation of Ohio Application April 19, 1928, Serial N0..271,184 26 Claims. (Cl. 200-97) My invention relates to inductively operated A non-magnetic member 17 in the form of a devices, but is shown in the present instance in cylindrical sleeve as shown surrounds the lower the form of a relay. This invention relates also portion of the core member 15. The cylinder to electric systems in which the said devices are extends up through the top of the casing 10. A

incorporated. I have shown a system of this type magnetic ring or bushing 18 surrounds the cylo for accelerating an electric motor. inder and is screwed into an opening in the top An object of this invention is to provide an of the casing, there being an air gap 18' between electro-responsive device suitable as a time delay the bushing 18 and the cylinder 17. relay which will be more efiectivein its operation A winding 19 is seated within the casing and 19 than devices of this class heretofore used. surrounds the core member 14 and that part of Another object is to provide an electro-responthe cylinder 17 which is below the top of the sive device and apparatus of the type above recasing.

vferred to in which the parts are exceedingly sim- The cylinder carries the disk contact or switch ple and so arranged as to operate efliciently for member'20 adapted, when the cylinder is in its a great length of time without requiring service lower positions, to bridge a pair of relatively Lil or repair. fixed contacts 21 of conventional resilient type, 70

A further object is to provide an improved and in its upper position to bridge a pair of simmethod of.controlling a time delay relay. ilar relatively fixed contacts 22. It may be desir- A further object is to provide an electro-reable in some instances to omit one or the other 53 sponsive device capable of embodiment in a time of these relatively fixed contacts, as in Fig. 3 delay relay which operates very rapidly and where only 77 the lower fixed contacts are used. 75

powerfully from an idle condition and which re- Fig. 2 shows one of the fixed contacts 21 supturns to said condition at slower speeds, variable ported by the arm 23 on the slate 11. as desired, The magnetic cover 24 is seated on the top of A specific object is to provide an improved the casing and against the slate 11 and has electro-responsive device of the type herein shown the magnetleplug 25 screwed into its top in axial including circuit controlling contact elements alinement with the core member which extends which cooperate with a definite and forcible wipup into the cover, leaving an air gap 26 of desired ing action, particularly to close such contacts. length between the plug and the core member 15. 5) Further objects relate to the general improve- The apparatus described may be considered as ment of electro-responsive apparatus of the type a current transformer with a movable secondary herein shown and described. comprising the cylinder 17, or a single turn cir- Other objects and features will become apcuit. The primary of the transformer is the parent from the following description relating to winding 19. the accompanying drawing showing the pre--- When current is established in the operating ferred form as adapted to serve in a motor-concoil, the growing direct current induces a sectrol system. v I, ondary current in the cylinder 17. Repulsion be- Referring to the accompanying drawing, Fig. 1 tween the cylinder and the winding 19 causes the is a front elevation of an induction device concylinder to move upwardly and open the contacts taining this invention, the upper casing being in and 21. When the current ceases to grow in vertical section; Fig. 2, a central vertical section the operating winding 19, there is no secondary on the line 22 on Fig. 1, the core B bein in current in the cylinder, and it begins to fall down sideelevation; and Fig. 3, a diagrammatic view through flux suitably provided across the gap of an electric motor system controlled by relays 18'. The flux in the air gap 18' variesinstrength shown in Figs. 1 and 2. in accordance with the strength of the current Referring first to Figs. 1 and 2, 10 designates a in the winding 19, being greatest when the curcasing of magnetic material having its open back rent in the winding is of great strength and being side mounted on the base or slate 11. The verweaker when the current in the winding is of a tical magnetic core B has a threaded steml2 small value. The rate of the return of the movscrewed into the bottom of the casing, a jam-nut able member (cylinder 17) is governed by the 13 being turned up on the stem and against the strength of the fiux in the air gap 18', being slow bottom face of the casing. The lower' member when the flux strength is great and being rapid or part 14 of the core B is of larger diameter when the flux strength is small. It is clear therethan the core member or part 15 above it. The fore that the rate of the return of the movable annular shoulder at the junction of the core member and hence the length of time required to members 14 and 15 is marked 16. close the contacts controlled by the movable memher are modified by variations in the strength of the current in the winding 19b c Motion of the cylinder 17 in the magnetic field causes electric currents to be generated in the cylinder, retarding its downward movement by which a time element is obtained. At the end of the downward stroke of the cylinder, the contacts 20 and 21 are closed.

The contact arms 23 can be adjusted, as by bending the arms 23 to the right degree or by other adjusting means wellknown to those skilled in this art, so that the movable member 17 when idle is supported by the contacts 21', as shown in Fig. l, leaving a small space between the lower end of the member 17 and the shoulder 16. After the cylinder, in its retarded downward movement, closes the contacts 21, cutting off current to the winding 19 by the closure of the contactor S (closed by the contacts 21) the rapidly decreasing flux in the magnetic circuit of the relay causes a momentary downward pullanalogous to a. sucking action-on the member 1'7. This movement produced inductively each time the contacts are closed, causes a wiping action of the contacts 20 on the contacts 21, due to the relative yielding between the contacts 20 and 21, which keeps the contacts clean and thereby assures their efliciency.

It hasbeen demonstrated that the retarding forces due to induction of current in the member 17 act on both major movements of this member. The restraining forces act on the member 17 as it rises and prevent the member 1'7 from jumping too high or with so much force that the member 17 impinges on the upper portion of the casing. The restraining force on the member 1'? is easily demonstrable by increasing the air gap at 18, it being found that when this air gap is made larger the member 1'7 jumps much higher.

'A further result of increasing the size of the air gap at 18 is to decrease the delay period of the member 1'? in returning to the position which closes the contacts 21.

The magnetic circuit of the relay has two parallel paths: one through the core B, the case 10, the bushing 18'and the air gap .18". The second path is through the core B, the casing 10, the cover 24, adjusting plug 25 and the air gap 26 between the core B and the adjusting plug 25. In both cases the core member B acts to increase the flux set up by current in winding 19.

4 At the initial energization of the operating coil,

the cylinder 17 quickly rises, retarding magnetic flux through the air gap 18' not having had time to establish itself to full strength. When the cylinder begins to descend, the fiux in the air gap 18 through the bushing 18 is of maximum strength due to the motor current passing during acceleration through the operating winding 19, so that the speed of the downward movement of the cylinder is much slower than its speed of the upward movement. Actual tests have demonstrated that the upward speed is several hundred times the downward speed. The adjusting plug 25 is provided to vary the air gap 26 between the plug 25 and the core B, by means of which more or less flux is shunted away from the air gap 18', thereby changing the strength of the magnetic field in the said gap. By these means the time of the downward motion of the tube can be adjusted at will.

Referring to Fig. 3, the operation of the push button switch 8 establishes an obvious circuit between the current supply lines 27 and 28 and through the operating winding 30 of the main contactor S, and causes the contactor to close its contacts 29, whereupon motor current flows from the line 2'7 through the contacts 29, the winding 19 of the relay C, and the entire resistor R, the

armature A and the series field F of the motor to the supply line 28. At the time this circuit is established, a circuit is established through the auxiliary contacts 31, the operating winding 32 of the acceleration contactor S and the contacts 20 and 21 of the relay C, which shows diagrammatically the relay of Figs. 1 and 2. However, the quick-acting inductively-operated relay C opens its contacts 20 and 21, before the magnetically-operated switch S can close its contacts 33. Consequently, the contactor S remains open. Then the cylinder 17 of the relay C begins slowly to descend due to the cylinder cutting magnetic lines in the air gap 13, and after a certain time-limit the contacts 20 engage the contacts2l, which close the circuit of the winding 32, whereupon the contactor S closes, motor current then flowing from the contactor S through the contacts 33, the winding 19- of the relay C, similar to the relay C, and the left hand portion only of the resistor R to the motor. The motor current and speed increases, but the operating winding 34 of the acceleration contactor S2 remains open because the circuit of the winding 34 is opened at the contacts 20 and 21 of the relay C, which were opened by the quick-acting inductive member 17 of relay 0' before the magnetic contactor S2 could operate. When the motor current reaches its maximum, the cylinder 17 of the relay C begins slowly to dr0p, and after a time delay suflicient to make it safe to close the contactor S2, the contact member 20 closes the contacts 21 of the relay C, thereby closing the circuit of the winding 34 through the auxiliary contacts 38 on the contactor S, whereupon the contactor S2 closes its contacts 37, motor current now flowing in series from the line 27 through the contactors S, S and S2 to the motor. The resistor R and the windings of the relays C and C are now short-circuited.

In order that the contactor S shall remain closed after the starting button 8 has been released and returned to the position shown, a maintaining circuit for the winding 30 is created by the auxiliary switch 35 which-is closed by the contactor S as it closes, in a manner well known.

36 is a shunt field for the motor, its circuit being closed as soon as the contactor S closes.

In the system shown in Fig. 3, the operating coil of the contactor is shown to be initially energized at the same time that the operating coil 31 of the inductively-operated relay is energized. The relay will open its contacts to prevent the operation of the contactor to be later controlled by the relay before the contactor closes because in' any magnetically operated contactor, time is required for the magnetic flux to build up in the magnetic circuit of the contactor before it can close, whereas the inductively-operated relay the greatest force for opening the contacts of the relay is experienced at the initial establish- :1,

The

magnetic field member energized by current in the winding, a non-magnetic movable member positioned to have current induced therein when a flow of direct current is established in the winding, and magnetic means for retarding the movement of the said non-magnetic member toward the winding while the winding is energized with direct current.

2. In an electromagnetic device, an electro-.

magnet, having two windings, one fixed and the other movable, and a magnetic field member, energized by a flow of current in one winding, the other winding being positioned to receive current inductively from the former winding when energized with direct current, whereby the move.- ble member is quickly operated in one direction, and means controlled by the magnet for delaying the movement of the movable member in the opposite direction.

3. In an electro-magnetic device, an electromagnet having a stationary primary winding and a movable non-magnetic secondary member in which current is induced when the primary winding is energized by direct current, contacts carried by the-secondary member, means whereby the contacts are moved quickly in one direction when the primary winding is energized by direct current, and means controlled by the value of flux produced by the electro-magnet for delaying the movement of the contacts in another direction.

4. The combination of an electromagnet having a stationary primary winding and a movable secondary winding, 9. pair of normally-dosed contacts operated by the said movable secondary winding, means controlled by the electromagnet for quickly opening the said contacts, and means controlled by the electromagnet for delaying the closure of the said contacts.

5. In an electro-responsive device, a supporting case, a magnetic core member mounted in the said case, a winding surrounding the core member, a current-conducting tube freely movable on the core member and extending partially into the winding, means for ejecting the tube at a relatively high speed when direct current in the winding is established, and means for causing the tube to return at a relatively slow speed while the winding is still energized with direct current.

6. The combination of an electromagnet having a stationary primary winding and a movable secondary winding, a pair of normally-closed contacts operated by the movable secondary winding, and means whereby the electromagnet retards the movement of the secondary winding to close the contacts.

7. In an electro-responsive device, a closed conductor, means for moving the conductor from its normal position, and means including a magnetic circuit having an air-gap enclosing the conductor for retarding the movement of the conductor to its normal position.

8. In an electro-responsive device, a nonmagnetic closed conductor, means for moving the conductor from its'normal position, contacting means operated by the moving conductor, and means including a magnetic circuit having an air gap enclosing the conductor for retarding the operation of the contacting means while the conductorreturns to its normal position.

9. In an electro-responsive device, a magnetic circuit having an air-gap, a gravity-operated closed conductor arranged to pass thru the airgap, and means for energizing the magnetic circuit to retard the downward movement of the conductor.

10. The combination with an electromagnet having an energizing winding and a conductor tube associated therewith, of magnetic means for directing the flux set up by the winding to cause the tube to be retarded in its movement, 'with a substantially constant current in the winding.

11. The combination with an electromagnet having an energizing winding and a conductor tube associated therewith, of magnetic means for directing the flux set up by the winding to cause the tube to be moved quickly against a restraining force with a varying current in the winding and to cause the tube to be retarded in its movement by the restraining force while more or less current flows in the said winding.

12. A direct current time delay relay comprising a winding, a non-magnetic current conducting movable member, normally-closed contacts adapted to be opened quickly by the movable member when direct current is initiated in the said winding, and means whereby a continuation of direct current in the said winding reacts upon the movable member to cause it to return slowly to its initial position and close the said contacts.

13. In a time delay relay, a frame, a winding supported thereby, a non-magnetic current conducting movable member adapted to be held in a given position by a restraining force, a set'of resiliently mounted contacts tending to force said movable member in a position away from said given position by the. resiliency of their mounting, and a magnetic circuit including said frame arranged to cause the flux from the said winding to act inductively upon the said movable member to open the said contacts quickly when a direct current is initially admitted to the winding, to delay a return of the movable member to its initial position to reclose the contacts while direct current continues to flow in the said winding and to act inductively on said movable member to move it against a resilient force of the con- 3.

tact mounting to the said given position when the said direct current ceases to flow in said winding.

14. In an electro-responsiye device,.an electromagnet having an energizing winding, a nonmagnetic movable element biased toward a given 1 position with respect to the winding, and magnetic means for increasing the flux set up by the winding to cause said element to be retarded during movement thereof toward said position.

15. In an electro-responsive device, a magnetic circuit having an air gap, a non-magnetic current conducting element biased to a given position in said air gap, means whereby a rapidly increasing unidirectional flux in the magnetic circuit causes the element to be moved away from said biased position, and means including said magnetic circuit whereby the said element is caused to move to its biased position at a speed depending upon the value of unidirectional flux in the magnetic circuit.

16. In an electro-responsive'device, a magnetic circuit having an, air gap, a movable member of non-magnetic current conducting material arranged to pass through the air gap, a winding for energizing said magnetic circuit, and means including said magnetic circuit disposed for causing the said member to pass through the said air gap more slowly in one direction when direct current flows in the winding.

17. In an electro-responsive device, an electromagnet, a non-magnetic member positioned to have current induced therein when the electromagnet is energized to cause movement of said member in one direction, means controlled by the value of flux produced by the electro-magnet for delaying the movement of said member in another direction, contact means on said member extending outwardly therefrom and cooperating means arranged to engage said outwardly extending means to control a circuit when said member is in one of its positions.

18. In an electro-responsive device, a non-magnetic movable member, a winding, means whereby a flux produced in said'winding when current is admitted thereto acts upon said member to move it against a restraining force in one direction, and means acted upon by the flux of said winding subsequent to the initial movement of said member whereby said member is moved slowly by the restraining force in the opposite direction, the speed of the movement being controlled by the value of current in the winding.

19. In an electro-responsive device, a non-magnetic movable member having a rest position, an electro-magnet, means whereby said member is acted upon by the energization of the electromagnet to move said member quickly away from its rest position, and means whereby said member is controlled by said electro-magnet subsequently. to move slowly toward said rest position in accordance with the value of energization of the magnet.

20; In an electro-responsive device, a movable member biased to a given position, a winding, means responsive to the initiation of uni-directional current in the winding for moving said member quickly away from its biased position, and means responsive to a continued flow of uni-directional current in said winding for effecting.

a slow movement of said member toward its biased position.

21. In an electro-responsive device, a movable member, said movable member being biased to maintain it in a normal position, a winding associated with said movable member and operable to move the movable member, quickly away from the normal position when the winding is energized with a given value of current, and means associated with the movable member whereby a unidirectional fiux generated by the winding as a result of continued energization of the winding with said given value of current efiects a slow return of the movable member to the normal position.

22. In an electro-responsive device, a movable member, said movable member being biased to maintain it in a normal position, a winding associated with said movable member and operable to move the movable member quickly away from the normal position when the winding .is energized with a given value of current, the movable member being responsive to uni-directional flux generated by the winding as a result of continued energization of the winding, the flux generated by the winding being operable to cause a slow return of the movable member'to the normal position.

it to the normalposition, and operable on continued energization to oppose the return of the movable member to the normal position, the force generated by the winding and opposing the return of the movable member to the normal position being of lesser magnitude than the force acting upon said movable member to move it to the normal position whereby the movable member is slowly returned to the normal position.

24. In a direct current electro-responsive device, a movable member, said movable member being biased to maintain it in a normal position,

a winding associated with the movable member and operable on the initiation of current in the winding to move the movable member away from the normal position against the force of the biasing means acting upon said member to move it to the normal position, andoperable on continued energization to oppose the return of the movable member to the normal position, the force generated by the winding and opposing the return of the movable member to the normal position being of lesser magnitude than the force acting upon said movable member to move it to the normal position, the force generated by the winding and opposing the return of the movable member being modified by variations in the strength of the current in the winding whereby the movable member is slowly returned to the normal position, the rate of the return of the movable member being modified by variations in the strength of the current in the winding.

25.-In a direct. current electro-responsive device a movable member, a winding associated with the movable member, a pair of contacts, one of said contacts being controlled by said movable member, the movable member being movable consequent upon the initiation of uni-directional current in the winding to efiect movement of the contact controlled thereby into engagement with the other of said contacts, means responsive to r the continued energization of the winding with uni-directional current and operable to oppose the movement of the movable member to efiect closing of said contacts, the means opposing the movement of the movable member being of lesser magnitude than the force moving the movable member irrespective of the strength of the current in the winding, whereby the movable member is slowly moved to a position to efiect closing of the contacts, the magnitude of the means opposing mcvement of the movable member being modified by variations in the strength of the current in the winding, whereby the time interval intermediate the initiation of current in the winding and the closing of the contacts is modified by variations in the'current in the winding.

26. In an electro-responsive device, a winding for producing a magnetic fiux, a movable member biased to maintain it in a normal position, means responsive to the energization of the winding-and operable to move the movable member against the biasing means when the magnetic flux produced by the winding changes from a low value to a high value, and operable on continued energization of the winding'to oppose movement of the movable member to the normal position by the biasing force, the force opposing movement of the movable member to the normal position being of lesser magnitude than the biasing force tending to move the movable member to the normal position irrespective of the value of the current in the winding.

LEV A. TROFIMOV.

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