US1702988A

US1702988A - wright

Info

Publication number: US1702988A
Authority: US
Priority date: 1927-02-24
Publication date: 1929-02-19
Anticipated expiration: 1946-02-19
Also published as: GB291494A

Description

Feb. 19, 1929. 1,702,988

A. WRIGHT ELBCTRICALLY OPERATED ACTUATING DEVICE Filed March 21, 1928 3 Sheets-Sheet 1 Feb. 19, 1929.

A. WRIGHT ELECTRICALLy OPERATED ACTUATING DEVICE Filed March 21, 1928 3 Sheets-Sheet 2 Feb. 19, 1 929. V 1,702,988

, A. WRIGHT ELECTRICALLY OPERATED ACTUATING DEVICE Filed March 21, 1928 3 SheetsSheet 3 AVVIIY 70! ITTM/YA'Y Patented Feb. 19, 1929.

1,702,988 UNITED STATES PATENT OFFICE.

ALAN WRIGHT, OF LONDON, ENGLAND.

ELEC'I'RIOALLY-OPERATED ACTUA'IING DEVICE.

Application filed March 21, 1928, Serial 110. 263,462, and in Great Britain lebruary 24, 1927.

This invention relates to electrically op eratcd mechanism for imparting intermittent motion to switches, alvcs, and the like, and. it has for its object the provision of a mechanism that is of simple construction, of robust character, and is cheap to produce, A further object oi this invention is to obtain a positive action in two directions so as to avoid the use of springs, counterweights and like devices, to etfect the return movement An other object of this invention is to economize in current consumption. A further object of the invention is to give an increased starting torque, and a still further object is to enable a greater torque to be produced in one direction than in the other.

I attain these ends by a construction which comprises essentially a field magnet, an armature coacting with said. magnet the one having rotationalv movement relative to the other, stops to define and limit the movement of the rotational element, a tapped coil on one of said elements, a commutator arranged to move in unison with the rotating element and adapted to control the circuits through the tapped coil and the coil offthe field margnet. it same is of. the electromagnetic type,

brushes which coact with said commutator,

electric couplings between the commutator and the coils of the armature and: the magnet it so fitted and means for elosing'the: electric circuit through the commutator and its brushes.

In the accompanying drawing which forms I part of this specification Figures-1 9 are diagran'm'iatic views showing various alternative forms of construction based on well-known electrical combinations of magnets and armatures, and Figures 10, 11, an'd 12, are views in front elevation, rwr elevation and side elevation respectively, of the form of the invention shown in diagram Figure 9 carried into practice; Figures 1-9 show the following constructional forms :-Figure 1 a fixed electro field magnet with a continuously wound coil and rotating armature having a tapped coil. Figure 2, a fined permanent field magnet and a rotating armature having a tapped coil; Figure 3, a fixed electro' field magnet having a tapped coil and a rotating armature having a: col'ltinuously woundcoil. I igture 4, a fixed electro field magnet with a tapped coil and a rotating permanently magnctic armature. Figure 5, a fixed armature having tapped coil and u rotating electro field magnetwith a continuously Wound coil.

Figure (3, a fixed armature with tapped coil anda rocking permanent field magnet. Figure 7, a listed permanent magnetic armature and a rocking electro field magnet with a tapped coil. Figure 8, afixed armature with a continuously wound coil and a rocking electro field magnet with tapped coil. Figure 9 is a modification of the type shown in Figure 1 in which the armatureprovided with an interpole on which the tapped coil is wound.

Throughout these views 1 designates the field magnet, 2 the armature, 3 the tapped coil, 4' and 5 the segments of the commutator, 6 and 7 the brushes which coact with said segments, 8 and 9 the couplings between the segments of the commutator and the ends of the

tapped coil

3,10 the coupling between the tapping of the coil 3 and one end of the coil 22 of the electro field magnet when such is employed, 11 the coupling between the other end of said coil and the

main supply

12, 13 the electric couplings between the

brushes

6 and 7 and the main 12, and 14 the switch between said couplings and the min 12, The segments of the commiitator and the brushes are so arranged that they arenot simultaneously in Contact when'the armature is at endure only momentarily in contamwhen the segments move from one posi-- tion to the other."

It'will be seen that it is immaterial whether the field magnet is fi'x'ed andthe armature ro tales as shown in Figures 1,2, 3, 4, and 9, or whether the armature is fixed and the field magnet rota'tes as shown in Figures 5, 6, 7, and 8-, so longas the commutator is arranged to mo ve with the rotating element, and it is also immaterial whether the tapped coil is mounted on the armature as shown in Figures 1,2, 5, 6, and 9, or on the magnet as shown in Figures 3, 4, 5, 7, and 81 The coil 3 in all cases is tapped substantially at the centre of its length but this is not obligatory so long as each part of it'is suflicient to energize the element on which it is mounted.

The" two ends of the tapped coil 9 are in electric couple with the two segmen-ts and 5 of the commutator and the tapping of said coil is in circuit with the main 12 either through the coil on the element on which the tapped: coil is not mounted as shown in Figures 1, 3, 5, 8, 9, and 10, or direct as shown in Figures 2, 4, 6 and 7. When the tapped coil 3 is mounted on the electromagnet and the armaturehas a continuous wound coil oneend of" the armature coil is coupled to the segvment 4: of the commutator and the other end to the tapping of the coil 3, but when the armature is of the permanently magnetic type the ends of the tapped coil on the electromagnet are coupled to the two

segments

4 and 5 of the commutator.

Two stops are provided to limit the movement of the rotating element the positions of said stops being such as will bring the retating element to rest with the poles of the armature in juxtaposition to the entrant curves of the pole pieces of the magnet. It will be understood that the motion of the rotating element is only through apredetermined are so that the movement is in effect a rocking one. In the construction shown in Figures 10, 11, and 12, the stops are formed by the ends of a curved slot 15 in the frame 16 carrying the field magnet in which a pin 17 carried by the armature moves.

In operation, assuming the parts to be in the positions shown in Figures 18, if the switch is thrown over to complete the circuit through the brush and segment of the commutator at .the time in contact with one another, current will flow through one end of the tapped coil thereby energizing the rocking element and setting it in motion, the direction of rotation depending on which end of the tapped coil theeurrent enters. The eittect in all cases is to bring the poles of one of the elements into magnetic opposition to the poles of the other element which will cause the rotating element to rock until it comes into contact with the other stop and at the same time the electric circuit in the relative half of the tapped coil is interrupted by one of the segments of the commutator moving out of contact with its co-operating brush and by the same movement the other segment of the commutator and its brush are brought into contact with one another thus resetting the device for the reverse operation. This movement also brings the pole pieces of the armature and field magnet into such relative positions that when the switch is moved over to the opposite contact, the electrical current is then caused to flow through the opposite half of the tapped coil from the opposite end, thus reversing the polarity of the magnetic field set up by the tapped coil; the magnetic polarity of thefield set up by the continuous, i. e. untapped coil, being unchanged.

It will therefore be seen that no springs,

weights or the likeare required to move the rocking element in either direction.

It will be understood that the motion of the rocking element is taken either directly from said element or from the shaft 18 which carries it. It the device is intended to operate an electric switch same can be conveniently embodied with the device as shown in Figures 10 and 12 in which the switch comprises two rent passing through one path in the tapped coil 8 energizes the armature and determines the magnetic polarity of thetwo poles a, Z), and the polarity of the interpole 23 is the same as that of the pole b. The resultant effect of the interpole 23 and the pole 7) 7 that of a single pole located somewhere be tween these poles. This resultant etl ect is greater than that of pole Z) without the inter pole 23, and results in higher startin torque and an increased rapidity of action. To still further increase the starting torque the axis of oscillation of the rocking element is ar ranged eccentrically in relation to the centre of curvature of the poles of the other part so to provide an air gap of a varying radial depth as shown in Figure 9.

When it is desired to obtain a greater torque in one direction than in the other the one part of the tapped coil is wound with a conductor having a different specific resistance from the coil used in winding the other half, or the same result may be effected by windingboth halves of the tapped coil with the conductor having the same specific resistance throughout and inserting an inde-' pendent external resistance in one or other of the alternative circuits at any convenient point between the operating switch and one or other ends of the tapped coil.

The segments of the commutator and. the brushes are preferably arranged in the wellknown manner to form an automatic blow out for quenching any are that may be formed between the brushes and the commu tator.

What I claimv is 1. An electro-magnetic device comprising a field magnet and an armature coacting therewith one having rotational movement relative to the other, stops to define and limit the movement of the rotating element, a tapped coil on one of said elemens, a commutator rotating in unison with the rotating element and adapted to control the circuit through the tapped coil, and brushes coacting with said commutator so as to open and close said electric circuit. 1

2. An electro-magnetic device comprising a field magnet and an armature coacting therewith one having rotational movement relative to the other, stops to define and limit the movement of the rotating element. a

tapped coil on one of said element-s, means for increasing the starting torque of the rotating element, a. commutator arranged to rotate in unison with the rotating element and adapted to control the circuit through the tapped coil, and brushes coacting with said commutator, so as to open and close said electric circuit.

3. An electro-magnetic device comprising a field magnet and an armature coacting therewith one having rotational movement relative to the other, stops to define and limit the n'iovement of the rotating element, atapped coil on one of said elements, a comm utator arranged to rotate. in unison with the rotating element and adapted to control the circuits through the tapped coil, brushes coacting with said commutator, means for closing the electric circuits through the brushes and commutator, and means for increasing the starting torque of the rotating element.

4. An electro-magnetic device comprising a field magnet and an armature coacting therewith one having rotational movement relative to the other, stops to define and limit the movement of the rotating element, a

tapped coil on one of said elements, a commutator arranged to rotate in unison with the rotating element and adapted to control the circuits through the tapped coil, brushes coact-ing with said commutator, means for closing the electric circuits throu h the brushes and commutator, and means for giving the rotating element an increased torque in one direction of its movement.

5. An electro-magnetic device comprising a field magnet and an arn'iature coacting therewith one having rotational movement relative to the other, stops to define and limit the movement of the rotating element, a tapped coil on one of said elements, an interpole carried by the element having the tapped coil, a comn'iutator arranged. to rotate in unison with the rotating element and adapted to control the circuits through the tapped coil, brushes coacting with said comn'iutator, means for closing the electric circuits through the brushes and commutator, means for increasin the torque of the rotating element in both directions of its movement.

ALAN WVRIGHT.