US1043207A - Automatic self-starter for motors. - Google Patents

Description

LH. H. CUTLER.

AUTOMATIGISBLF STARTER POR MOTORS. urLmuIoN'rILnD APB. a, 1904.l BBNEWBD MAR. 2.9, 1912.

.Patentedflvom 5, 1912.

2 slums-s111121 1.

H. H. CUTLB-R. AUTOMATIC SELF STARTER POR MOTORS. APPLICATION IILED'APBLQ, 1904. RENBWED MAR. 29. 1912.

150432m/- Patented N0v.5,1912.

2 SHEETS-SHEET 2.

- UMTED srnrns riiivfr marion.,

HENRY CUTLER, O1?" MILWAUKEE, WISCONSIN.

Specification of Lessico?. i

AUTOMATIC SELF-STARTER FOR MOTORS.

Lesers Patent'. Patented Nev. 5, 1912.

Application filed pril 9, 1904, Serial No. 202,311. Renewed March 29, 1,912.. Serial No. 687,27.

To all whom t may concern:

Be it Iknown that l, HENRY H. CI'TLER, a f citizenv of the United States, residing at Milwaukee, in the county of Milwaukee and 5 State of ll'visconsin, have invented new and useful Improvements in Automatic Selt- Starters for Motors, of which the following is a full, clear, concise, and exact description, reference being had to the accompany- 'ing drawing, forming, a part of this specification.

Iii-v invention relates to a self-starter for electric motors. 11i-starters of this class a solenoid or electromagnet is usually em- 15l ployed which, when energized, is adapted to' m'ove the Contact arm of the starting box or lrlieostat across a series of terminals to gradually remove the resistance from the armature circuit, thereby gradually starting the motor. Then the Contact arm has been moved to the on position. itis usual to provide some means. for retaining the contact arm in this position without neces sitating the passageof'tlie full operating currentthroughthe windings of the solenoid. I Itis tlieobject of the present invention to provide improved means for retaining the contact arm. in the on position after the same has been moved thereto through the agency of the operating solenoid.

-In accordance with my invention I provide supplemental electromagnetic means for vretaining the contact arm in the on .',posi'tiom whereby the electromagnetic means which serve to move the Contact arm to the on position in starting the motor, may be disconnected from circuit. I preferablyT provide a retaining electromagnet separate y and-distinctfr'oin the pulling electromagnet,

"40 'which serves tov move the contact arm, and -associate with the contact arm suitable switching mechanism. whereby the winding of the pulling magnet is removed from circuit when the working stroke of the con- 45 tactvarm has been completed.

`One form of apparatus tor carrying out my invention I have disclosed in the accompanying drawings, in which:

,Figure 1 is a front elevation of my device; Fig. 2 is a side elevation thereof; and, Fig. is a diagrammatic view of the circuits?? einployed. 'In the embodiment ofmy device which .I have worked out as the preferred construction, uponV an insulating base 1, of slate or marble. .or other .suitable materiali adapted to be secured to the wall or other vertical support, a resistance controlling solenoid 2 is mounted. The solenoid is provided with a trame 3, having lugs or feet 4 bolted to the base l to support the solenoid. in position upon the base. Suitable rlieostat contacts 5 are also secured upon'the base 1 by meansI of screws or in any other desired manner. A suitable operating'lever 6 carries a suit'-l able Vcarbon brush T atone end thereof,-l. which is'normally pressed upon resistance contacts-5 by the coiled spring 10 mounted upon the pin 9. The lever is secureduppnl .l the plate 1 by means of a plate 8'boltf'et to the base plate 1, having a projecting. p" upon which the lever 6 is pivoted. lever 6 has a rearwardly projecting arm' 11 to which is attached the piston rod-12 of the dash-pot 13. The piston l-l of the dashpot 13 is provided with suitable ports 15 extending therethrough, which are adapted to be opened and closed by the movable plate or valve 16, carried upon the lower end of the piston rod 12.'. At the lower end of '30 the dasli-pot 13 are provided by-passes 13a, having ports 13b and 13C, which open into the chamber of the dash-pot. The dash-pot' 13 has a suitable 'projection 17, by which it is suitably pivoted.v as yat 18, to a downwardly extending plate 19.

The4 core 2O of the solenoid 2 is adjustablv secured at its lower end to a connecting link v 21, which is pivotally secured to the lever or arm 6 and the upper end of the core is 90 adapted' .to move into engagement with a coiieesliaped stop 22, secured in position by the nut 23, and which permits a uniform movement of the core and thereby the lever 6; pon the inner face of the arm or lever 6 is mounted a suitable spring contact 2l adapted to make engagement with an acljustable contact 25 mounted upon the plate 1,whieh contact is electrically connected. with the lastof the series of .contacts 5,100 thereby, when the lever is in' its tinal posir tion, relieving the lever of part of the motor current and preventing the overheating of the lastcontact.

`Secured to the outer end of theleveijfis :105 a bracket. having arms 26 and 27 extending-- overthe front end of the lever and over the.

upper sidev thereof being held in position; *f by screws 28, 28, and having at its outerand? upper` end a projection 29, to whichwisfll' magnet 31,- mounted upon the base plate 1, and having suitable magnet poles 32 and 33. rlhe wedgosiiaped armature member 23 is adapted, when attracted, to lit within the V-shaiied oiwning formed by the tapered sides 34 and 35 ot the magnet poles 32 -anc 33.

A binding post 3G is secured to the trout tace ot' the plate 1 and has secured thereto by nut 37 one end ot a spring plate 38, which forms a switch connection with a. second binding post 3l). rThe spring plate 33 has downwardly extending projection 4() adapt.- ed to malte eoni'iection with the inclined tace 4.1, ot an adjustable contact 42, secured to the binding post 3). lVhen the lever is in the full on position, a pin 43 carried thereby is adapted to engage the spring` plate 38,. and more thel projection 4() out ot engagement with the contact 42.

vIn Fig. 3 the. circuits and other apparatus involved in the system are shown.' A solenoid switch 44 is employed tocoi1itrol the circuit to the motor 45 and any suitable switch 46 controls the operation ot the switch 44. The plus andininus sides ot the power circuits are indicated respectively by the numerals 47 and 4.3/ A main switch 45) is provided tor closingv the circuit through thel several parts ivitlitlie main line.

The operation qt'tie device would bons follows: Assuming the main switch 49 and the switch to be closed, circuit may be traced from the 'pliis'side of the line through conductor 47,;through the winding ot the solenoid 445,;thrrmgh switch 4G, conductor 49, the first ot the series ot' contar-,ts 5, contact lever C and back to the opposite main 48, by conductor 50. This energizes the winding ot' the solenoid and causes contact lplate 51 to eoimect'the terminals 52, 53.

Current will then low through the conductor 47, terminal 52, contact plate 51, terminal 53, conductor 54, conductor 55, through the winding of the solenoid 2 to terminal 39, across the switch 3S, through conductor 56 and thence by conductor 50 to the opposite side 48 ot the main. At the same time circuit is closed by the operation of the contact 51, through the field winding 5,7. of the motor and the circuit may be traced by conductor 47, across the switch 51, conductor 54, eld winding 57, conductor 5S, through the winding ot the magnet 31, thereby energizing the same through oonductor 59, and thence by conductor 50 to the opposite main 48. The winding of the solenoid magnet 2 being energized, the Ysame will attract its core and move the lever 6 across the contacts 5, 5, thereby cutting out the resistance 60 in the armature circuit and starting the vmotor in operation.

The lever 6 normally bridges the iirst two contacts and short ci its a resista-nce G1, which is inserted in the circuit of the wind- Lorano-r ing of the solenoid 44, but as soon as the .lever is moved otl' thel liz-st ot the series of contacts 5, the resistance (5l is inserted in circuit, tlierel'iy decreasing the strength of the winding of the solenoid 44 to such a degree thatI while it will serve to maintain the Contact 51 in a closed position, if, for any reason, the current is cut otl', it will not again operate to close the switch. When the lever (3 reaches the last position, cutting out all the resistance GO in the motor armature circuit., the pin 43 mounted thereon will engage the switch 38, moving the same out ot Contact with the terminal 42 and thereby open the circuit through the winding ot' the solenoid 2. By this means only the retaining magnet 31 is retained in circuit across the line and this magnet is only ot' sntieient strength to hold the lever in its on position. A conductor (3 connects the hub of the contact arm (3 with the second Contact, so that in case the contact between the contact arm and the contacts should be detective the armature current will still tiptel a path through conductor (i and the resistance coils.

As the lever (l n'ioves across the series of contacts 5 the piston 15 Will move downwardly into the dash-pot 13 andas the ports 15 are closed by this movement the move. ment ot' the lever will be retarded as the oil cannot freely pass around the piston. As soon, however, as the piston reaches a point intermediate of the ports 13b and 13, the oil will pass freely through the ley-pass 13 troni one side ot the piston to the other, allowing the piston to move rapidly to the end of its stroke. At the saine time the ari'nature 3() carried by the lever G will be near the poles ot the magnet, 32 which will exerta slight pull on the armature, thereby assisting the solenoid Q.. This causes a rapid movement of the lever over the last part of its' movement and the switch arm '3S is rapidly caused to break contact with its contact 42, thereby preventing a reing at this point.

It Will thus be seen that I have provided means for automatically starting the motor as soon as the switch 46 is closed, but as soon asthe motor is started,l the pulling magnet is cut out of circuit and a retaining magnet only serves to hold the controller arm in the on position. By this arrangement, as soon as the current, for any reason, is cut off from the field windings, the retaining magnet 31 will be denergized and the same will permit the controller arm f3 to move to its initial position, through its own weight, the piston 14 offering but little resistance in this movement as the ports l5 are generi by the downward movement of the ever and the oil is permitted to freely pass therethrough. f

lVhile I have shown and described one form ot' my invention. it Will be understood duce the current through the magnet to such' a degree that the same is only of sutlicient strength to hold `the operating lever in position, but itwill be understood that I do not wish to limit myself to this construction as there are numerous other ways of arrang- :ing the retaining magnet'and the pulling magnet without departing from the spirit of mykinvention. For instance, the retaining magnet may be connected in an independentcircuit and 4suit-able resistance insertiwl to reduce its strength, or the retaining magnet maybe so arranged thatl its circuit may be closed only when the circuit is opened throughthe pulling magnet, or the retaining magnet may be arranged in an independent circuit which is normally open. but which is adapted to be closed when the circuit of the -pulling magnet is opened. The above arrangements are cited merely to show the .general changes which may, be made in my device and-arel not intended to be an exhaustive enumerat-ionof the various changes which may be made.

Having thus described my invention what I claim as new and desire to secure by Letters Patent is:

1. In a starting device for electric motors, in combination, a supporting panel, a series of resistance contacts mounted thereon, fa resistance varying element pivoted upon said base and carrying atl one end a Spring pressed contact adapted to` engage and move over said series of ccntmts a solenoid mounted vertically on sald panel and having'a movable plunger connected to said element for operating the same, a dashpot having its piston connected to a rearward extensionv on said element Vfor retarding the operation of said element in one direction, a switch mounted on said panel between said element and said solenoid and arranged to be actuated by said element as itreaches the limit of its movement to denergize said solenoid, a, retaining magnet mounted on said base contiguous to said solenoid, and a pivoted armature carried at the forward end of said element and arranged vto be attracted by said. retaining magnet to hold said element at the limit of its movement aft-er dcenergization of said solenoid.

2. In a starting device for electric motors, in combination, a series of contacts, a starting resistance connected thereto, an electro magnetic-ally operated switch arm movable over said contacts to control said starting resistance, an electromagnetically operated main switch, said switch arm, when in its initialposition, being included-in and adapted to complete the circuit of the ope;v ating winding of said main switch, a resistance arranged to be short-circuited by said switcharm when in initial position, and to be inserted in circuit with 'the operating winding of said main switch when said switch arm is actuated -to prevent reclosure of said main switch until said switch arm is returned to initial position.

. In witness whereof, I have hereunto subscribed my name in the presence of two witnesses.

. HENRY H. CUTLER. Witnesses:

F.S. WJLHorr, F. R. BACON.

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