US897497A

US897497A - Starting and speed-regulating rheostat.

Info

Publication number: US897497A
Application number: US41253908A
Authority: US
Inventors: Frank J Seabolt
Original assignee: General Electric Co
Current assignee: General Electric Co
Priority date: 1908-01-25
Filing date: 1908-01-25
Publication date: 1908-09-01
Anticipated expiration: 1925-09-01

Description

PATENTED SEPT. 1, 1908.

I P.-J. SEABOLT. STARTING AND SPEED REGULATING RHEQSTAT.

APPLICATION FILED JAN. 25, 190B.

hwendof. Frank J. Seabolfif.

UNITED sTATEs PATENT OFFICE.

FRANK J. sic/incur, or srii-icNnc'ranv, NEW Your, AssIcNoR'ro GENERAL ELECTRIC coMrANY, .A GORPORATION or NEW YORK.

STARTING AND SPEED-REGULATING REEOSTAT.

To all whom it may concern:

Be it known that I, FRANK J. SEABOL'I, a citizen of the United. States, residing at Schenectady, county of Schenectady, State of New York, haveinventcd certain new and useful Improvements in Starting and Speed- Regulating Rheostats, o'l' which the following is a specification.

This invention relates to devices for controlling electric motor circuits and has for its object the provision of a device oi this character in which the starting and speed regulation of the motor may be accomplished in a reliable, simple and'eifieient manner.

My invention relates more specifically to devices for starting a motor and thereafter varying the 'speed.

In carrying out my invention I provide in connection with starting and s eed regulat,

ingresistances, a single centre ling arm arranged to control both of said resistances and thereby accomplish both the starting and s eed regulation. In in revious patent 0. 852,851, I have descri ed a device of this character in which the controlling arm is biased to the off position so that upon failure of'voltage it will always return to a protective position. In this rheostat the arrange ment is such that when the controlling arm moves to vary the starting resistance the field resistance is short-circuited and while the field resistance is being varied the armature resistance is short-clrcuited. For certain purposes I have found that a rheostat of Patented Sept. 1, 1908.

Serial No. 412,639.

and 12 forming the terminals of the field and armature resistances 13 and 14 respectively. A controlling member 15 is pivoted concentrically with said studs so that the

contacts

16 and 17 at its free end move over the re spective studs to vary the resistance in a wellknown manner. The handle of the controlling member is provided with a switch comprising a plunger 18 adapted to be moved longitudinally of the handle against the ten- 6:,

sion of the spring 19. This plun er. is provided at 1ts ower end with a bri gin con ,tact 20 arranged to bridge contacts 21 or the Adjacent to coils control the bridgiin contact 25 to close the armature circuit. he coil 22 is of sufficient strength to actuate the contact 25 while the wlnding 23 is only sufiicient to hold the contactor in a raised position. A switch arm 26 is pivoted at 27 to the magnet frame so as to be held aainst the tension of the sIpring 28 when t e magnet is energized.

his arm is rovided with contact strips 29' and 30 insu ated from the arnn The strip- 29 is arranged to bridge the

contact studs

31 and 32 when the arm is moved into contact with the magnet while the strip 30 engages the contact segment 33 at all times. When in the position shown in the drawing,:the

position of the controlling arm 70 35 this type, in which the controlling arm is not .biased to the off position, is desirable. I

have also found in some cases that it is objectionable to open the circuit uponthe contact studs. I therefore provide an electromagnetic switch which always opens the circuit in addition to a controlling arm which may be left in any osition.

Other features 0 novelty will appear in the course of the following-specification in which I have shown my invention embodied in concrete mechanism for purposes of illustration.

strip 30 engages contact stud 34 while when it is moved up against the magnet it enga es stud 35. The winding 22 is energized iy means of a stud 36'arranged to be engaged by the cont-act 17 when the arm is in its mitial position but it will be denergized after the initial movement.

The arrangement of circuits and mode of operation are as follows: when 1t is desired-to start the motor the ,arm 15 is moved to the night so as to engage the studs 11,12 and 36. The winding 22 is thereupon energized to In the accompanying drawing disclosing my invention, F1 re 1 1s a plan view of the device'showing t e circuit connections and Fig. 2 is a detail view of the controlling member partly in section.

Referring to the drawing, 10 is an insulating base ofslate or sea stone provided with close the switch 25 as follows: from the positive main to the stud 36 thence through winding 22 and back to the negative mam.

The switch 25 being closed, the armature cir- 55 two sets of concentric y-arranged studs 11 At the same time the field resistance 13 is no short-circuitd as follows: from the positive main through conductor 39, contact strip 30, conductor'40, field F and back to line. armature resistance may now be cut out by movin'g'the arm to the right in the usual way.

When the contact 's broken at stud 36, wind ing 22 will be deenergized but in the mean time the plunger switch 18 in the handle has been pressed down so as to brid e the contacts 21 thereby energizing the ho ding winding 23 as follows: from the positive main to conductor 41, contact 20, conductor 42, winding 23 conductor 43 and back to the negative main. This will hold the switch 25 closed, but if the operator should release the switch in the handle, thc armature circuit will be immediately opened and it will be necessary to return the arm to starting position in contact with the stud 36 in order to again close it. When the arm.15 reaches running position, the switch arm 26 is forced over by the In 44 into engagement with the magnet 24. 'Ihis causes the armature resistance to be short-circuited across from con .ductor 39 to conductor 38 by the conducting moving the arm ack and forth over the studs 11. Upon failure of voltage the armature circuit will be opened. at switch 25 and the arm 26 will return in response to the tension of its spring so as to open the shortcircuit of the armature resistance and again close the short-circuit of the. field resistance. The switch 25. being opened in order to again close it, the arm must be brought back to the startin position.

It w' 1 thus be seen that I have provided a simple and efficient arran ement for both startin and regulating the speed of the motor by means of a single controlling mem ber in addition to means for protecting the rheostat from abnormal circuit conditions. 'While I have described ,m invention in connection with specific mec ianism and arrangement of circuits, it should be understood that I do not limit my invention thereto sin ce various modifications will suggest themselves to those skilled in the art without departing from the spirit of my invention, the scope of which is set forth in the annexed claims.

\Vhat I claim as new and. desire to secure by Letters Patent ol' the United States, is,---

l. A controlling device for elmt-tiic motors comprising pair of resistances each provided with contacts. a controlling member The the motor circuit through the armature resistance, and means controlled thereby for rendering said member ineffective to control one of said resistances when moved in one direction and the other of said resistances when. moved in the opposite direction.

3. A motor-starting and speed-regulating rheostat comprising an armature resistance and a field resistance each provided with con tact-s, a controlling member simultaneously engaging said contacts, an electromagnetic device arranged to be energized upon the initial movement of said arm for closing the motor circuit through the armature resistance, means for shru't-cirrmitiug the field resistance, and means crmtrolled. by said electromag netic device for opening said short-circuit and simultaneously short-circuiting the armature resistance when the controlling arm reaches running position.

4. A controlling device for electric motors comprising a pair of resistances each provided with contacts, a controlling member simultaneously engaging said contacts, an electromagnetic device for closing the motor circuit through one of said resistances, a switch in connection with said member for controlling said electroma :nctic device, and means controlled by said e ectromagnetio device for rendering said member ineffective to control one of said resistances when moved in one direction and the other of said resistances when moved in the other direction and simultaneously short-circuiting said switch.

5. A controlling device for electric motors comprising a pair of resistances each providcd with contacts, a controlling member simultancou sly engaging said contacts, an electromagnetic device for closing the motor circuit through one of said resistances upon the initial. movement-of said member, means for rcduoing the energy of said device from an ac tu ating to a holding current, andmeans controlled by said device for rendering said member ineffective to control one of said resista field resistance each provided with contacts, a controlling member simultaneously engaging said contacts, an electromagnetic device for closing the motor circuit through the armature resistance upon the initial movement of said member, a switch in connection with said member for controllin said electromagnetic device, means controfied by said device for rendering said member ineffective to control one of said resistances-when moved in one direction and the other of said resistances when moved in the opposite direction, and means for short-circuiting said switch when the controlling member reaches running position.

I 7. A motor starting and speed regulating rheostat comprising a starting resistance and a fieldresistance each provided with contacts, a controlling member simultaneously engaging said contacts, an electromagnetic device for closing the motor circuit through the armature resistance upon the initial movement of said member, means for reducing the-energy of said device from an actuating to a holding current after said initial movement, a swltch in connection with said member for controlli said electromagnetic device, means control ed by said device for rendering said member-ineffective to control one of said resistances when moved in one direction and the other of said resistances when moved in the opposite direction, and means for short-circuitmg said switch when the controlling member reaches running position.

8. A controlling device for electric motors comprisin a pair of resistances each provided with contacts, a controlling member simultaneously engaging said contacts, an electromagnetic device for closing the motor circuit through one of said resistances upon the initial movement of said member, a switch in connection with said member for controlling said electromagnetic device, means for reducing the energy of said device from an actuating to a holding current after the initial movement of said member, and means controlled. by said device for rendering said member inefiective to control one of said resistances when moved. in one direction. and the other of said resistances when moved in the opposite direction and simultaneously short-circuiting said switch.

9. A starting device for electric motors comprising a resistance, a controlling member therefor, an electromagnetic device for closing the motor circuit through sa1dres1stance upon the init al movement of said member, a switch in connection with said member.

for controlling the circuit of said electromagnetic device, and means controlled by said device for short-circuiting said switch.

10. A starting device for. electric motors comprising a resistance, a controlling member therefor, an electromagnetic device for closing themotor circuit through said resistance upon the initial mov ent of said member, means for reducing the energy, of said device from an actuating to a holdim current after said initial movement, aswitc in connection with said member for controlling the circuit of said device, and means controlled by said device ,for short circuiting said switch. I In witness whereof, I have hereunto set my hand this 23rd day of J anua 1908.

FRANK J. S ABOLT. Witnesses:

BENJAMIN B. HULL, HELEN Onronn.