US1744247A - Circuit controller - Google Patents

Description

Jam. 21, 1930. w. c. STEVENS 'ET A1.

CIRCUIT CONTROLLER Filed Nov. 26, 1923 2 Sheets-Smet l Ome/nce AZTKNEY Jan. 21, 1930. w. c. STEVENS ET AL 1,744,247

CIRCUIT CONTROLLER Filed Nov. 26, 1925 2 Sheets-Sheet 2 GW Sisma/vw @MMM WMM Gbe/umnv Patented Jan. 21, =1930 UNITED lSTA Es PATENT oFF'Icl-j WILLIAM C. STEVENS AND CLARENCE T. EVANS, OF MILWAUKEE, WISCONSIN, AS-

SIG-NORS, BY MESNE ASSIGNMENTS, TO CUTLER-HAMMER; INC., A CORPORATION OF DELAWARE CIRCUIT CONTROLLER Application led November 26, 1923. Serial No. 676,914.

type.

The invention has among `its objects to provide an improved motor starter of the enclosed type having its switch parts and starting resistance arranged in an exceedingly compact relation within a relatively small enclosing casing.

Another object is to provide a motor starter of the aforesaid character including a resistance element which is bendable to suit the space conditions between. the switch mechanism and the enclosing casing and which, due to its inherent structure, will retain the form into which it is bent.

Another object is to provide a motor starter having a resistance element of the aforesaid character, such element being complete in itself and including terminal devices to beV detachably secured to certain parts of. the switch mechanism.`

Another object is to provide a motor starter of the enclosed type including a resistance element of the aforesaid character which is arranged adjacent or in contact with a relatively large surface of the interior of the enclosing casing to provide for \rapid transference of heat from the element to the enclosing casi-ng., f 1 f Various other objects and advantages of the invention will hereinafter appear.

The accompanying drawings illustrate a motor starter embodying the invention but it should be understood that certain features of the invention are not limited to motor startl ers of the character shown but are capable of use`v in other relations.

In. the drawings,

"Figure 1 is a front elevational View of al motor starter embodying the invention, the cover of the enclosing casing being removed. Figs. 2 and 3 are vertical sectional views on lines 2-2 and 3 3 respectively, of Fig. -1.

Fig. 4 is a horizontal sectional view taken substantially on line 4--4 of Fig. 1.

3. As best shownn Fig. 1,

Fig. 6 is a schematic view ofthe starter and the circuit connections therefor.

Referring to the drawings, the same illustrate a motor startfer including switches 1 and 2, the former switch being adapted as hereinafter set forth to control the continuity of the motor circuit and the latter being adapted to include and exclude a resistance element R in the armature circuit of the motor. The switches 1 and 2 are mounted upon an insulating panel 3, such panel being secured to the rear wall of an enclosing Acasing 4, and, as hereinafter set forth, the resistance element R is adapted to be mounted within a relatively small space between the switch mechanism and the enclosing casing and is supported by certain parts of the switch mechanism.

More specifically, switch 1- includes a stationary contact 5 mounted upon a supporting post 6 fixed to base 3, and a co-operating movable contact finger 7 arranged in front of said'stationary contact and normally out of engagement therewith. Switch 2 includes a stationary contact 8 carried by a supporting bracket 9 fixed to base 3 and a co-operating movable contact finger 10 arranged to the rear of said stationary Contact and normally engaging the same. Contact ingers 7 and 10 are mounted upon supporting members 11 and 12 respectively, and said supporting members arepivotally mounted upon a pin 13 carried by a U-shaped magnet frame 14 iXed to the front 'face of insulating panel pin 13 is supported by spaced upwardly projecting lugs 15 and 16 on the front wall of magnet frame 14 and supporting member 11 is'p'rovided with spaced bearing portionsy 17-17 arranged on opposite sides of the former lug. while supporting member 12 is provided-rv wlth spaced bearing portions 18-18. ar-` ranged on opposite sides of the latter lug. Also, as best shown in Figs. 2 and 3, supporting members 11 and 12 are provided with upwardly extending projections 19 and 20, respectively., Contact finger 7 has its/lower end fulcrumed within a recess and the front face of extension 19 while contactnger 10 has itslower end fulcrumed within a recess in the rear face of ertension 20 and each of i contact' ngers is yieldingly held inen- 22 and 23, arranged vertically and in a plane itsv respective .supporting gagem'ent with device 21 of contending armature projection1l25'to be attracted by magnet 23 for retention of switch 2 in open position. As hereinafter set forth, magnet 23 maintains switch 2 in open position during starting of the motor, but as soon as the motor is brought up to speed a sprin 26 overcomes the restraining .action of sai \ma et and moves switch 2 to closed position. Spring 26 is held under compression between a projecting lug 27 on supporting member 12 and acup member 28 carried by a screw. 29,whichis threaded into the lower wall of 25 magnet-frame 14 and is adjustable forvariation of theY degree of compressionfoflfsaidspring. As shown in Figs. 1 and 3, the right hand bearing portion 18 of supporting member 12 has a projection 30 for engaging the front face of magnet frame 14 to limit outward movement of said member and the con-Y tact linger carried thereby under the action of spring 26.

The operating meansrfor switches 1 and.2 includes a cam member 31''1Xed to a square shaft 32 by a cap member 33. Shaft 32 has one end journaled in .the left hand wall of casing 4 and its opposite end fixedv to an operating lever 35 havin a hub portion 36 journaled in theright and wall of said casing. As shownin Fig. 2, shaft 32 has a lever 37 fixed' thereto and the same is biased to 'move in a clockwise direction by spring 38 having one end connected to said lever amaca? ber and the contact linger 10 into open position said stop engagesthe upper face of a projection 44b on supporting member 11 to move the latter in a direction for closure of contact linger 7. Contact linger 7 is retained in closed position by magnet 22, and upon release Bf the operating lever 3,5 the latter is heldin running position against the action creases as the speed of the and its opposite end connected to a pin`39 fixed to the-lowerwall of casing 4. Cam 3l, 'as shown in Fig. 3, is provided withcam surfaces 40 and 41, the former surface being arranged to co-act with a forwardly projectmg lug 42 on the left hand bearing portion 18l of supporting member 12 and the latter.

j surface being arranged to co-act with a downwardly projecting lug 43 on the right hand bearing portion 17 of supporting member 11. Referring to Fig. 5, it will be observed that the operatinglever 35 has extreme 0H and starting positions and an intermediate .running psition. Upon movement of the `lever 35 from its oli' to starting position cam surface 40 engages lug 42- to moversupportj ingmember 12 and the contact nger 10 carriedthereby into open position. Supporting member-.12 isprovided with a projecting lug 44 havmgan djustable. stop 44a mounted thereon and d ring movement of said memof spring 38 through engagement of cam sur- 'face 41 with the lug 43 on supporting member 11. By forcibly moving lever 35 from its running position to its olf Vposition cam surface 41 acts on lug 43 to move supportingmember 11 and contact 7 into open position against the restraining action of magnet 22.

The function and operation of the aforevdescribed starter will now be more fully set forth in connection with Fig. 6. The resistance element R, which will be hereinafter more fully described, has one terminal connected to'st'ationary contact 5 of switch 2 andl the other terminal thereof is connectedto the movable contact element of said switch and also to rthe movable contact element of switch f 1. As above set forth, upon movement of opfrom olf position to startingerating lever 35 -positionlthe contact linger 7 of switch 1 is moved to closed position and-*the contact finger 10 of switch 2 is moved to open position. With the switchesdn this position the armature of the motor is connected across lines L and L through switch 1 and resistance element R while the eld of the motor is connected across said linesby a circuit extending through switch. 1 and magnet 22. -Upon-release of the operatinV handle 35 switclrl is held in closedpositi switch 2 is vheld in open position by magnet 23, the latter magnet being connected across the terminals of resistance element R. With magnet 23 connected in this manner it is apparent that the attractive force thereof demotor increases and spring 26 is adjusted to overcome` the restraining action of said magnet to effect closure of switch 2 when the motor is brought up to a given'speed. Closure ofswitch 2, excludes the 'resistance element R from thev armature circuit of the motor. Q To stop the motor' operating handle 35 is forcibly moved f position to olf position n by magnet 22 while izo tubular jacket or casing 45, terminals46 and v 47 inserted in opposite ends of said'jack t and Arigidly fastened thereto, a helical resistor 4&

arrangedwithin said 'jacket andconnected to said terminals and insulation 49 compacted. within the jacket and around and about the resistor. The terminals 46 and 47 are insulated from the jacket 45 and each of the Vsame Yhas a threaded shankjpiovided with a pair 'of clamping nuts 50. The terminal 46 is secured to a projecting lug 51 on bracket 9 while terminal 47 is secured to a projecting lug 52v on magnet frame 14. The lugs 51 and 52 are provided with openings, for receiving their respective terminals, saidy openings beingV slotted to permit ready removal of the element from the front of the casing. The resistance element is originally straight and is shaped to suit the space conditions between the switch mechanism and the enclosing casing. The element shown in the drawings is shaped to provideva looped portion arranged in a vertical plane and a looped portion arranged in a horizontal plane below the magnet frame 13. lIt is apparent that due to the inherent structure of the resistance element the same can be readily bent and upon bending will retain its shape. Furthermore, it should be noted that the element is self-supporting and capable of being readily installed.

As shown in Fig: 1 the closing casing is of such dimensions that the right hand and bottom walls thereof are adjacent to the resistance element. Thus the heat generated in the resistance element will be rapidly transferred to the enclosing casing and it is to be noted that with an element of the aforedescribed construction the casing'can be brought into contact with the resistance element if desired. The enclosing casing is preferably formed in two parts consisting of a rear portion 4a and a cover portion 4b, said cover being arranged to carry the operating shaft 32 and lever C35 and being secured to the rear portion 4a by screws 515. The rear portion 4a of the enclos- .ing casing is provided with an opening in the upper` wall th/ereof for receiving the necessary conductors and the insulating base 3 is provided with suitable terminal devices 57 for connectionl to s uch conductors.

sAs before stated, the switch 1 is adapted to break the motor circuit and' in order to eliminatearcing between the contacts thereof, a magnetic blowout device is mounted upon the insulating panel 3. Such blowout device is of a conventional design and includes an electromagnet 58 ixed toinsulating base 3 and having pole pieces 59 arranged on opposite sides of the contacts of switch 1.

What we claim as new and desire to secure by Letters Patent is:

l. The combination with a circuit controller, ofv a' closely fitting enclosing casing therefor, and a resistor for said controller comprising an insulated resistance wire enclosed within a long tubular sheath bent to lie between -said controller and a plurality of the walls of said casing and in good thermal relation to the latter.

`EZ. The combination with a circuitcontrol- `ling device, of a casing closely surrounding said device, and a resistor removably secured to said device and suported thereby, said re-

Images