US2318488A

US2318488A - Circuit controlling device

Info

Publication number: US2318488A
Application number: US373992A
Authority: US
Inventors: Richard B Hunter; Harold L Mekelburg
Original assignee: Cutler Hammer Inc
Current assignee: Cutler Hammer Inc
Priority date: 1941-01-10
Filing date: 1941-01-10
Publication date: 1943-05-04
Anticipated expiration: 1960-05-04

Description

May 4, 1943. R. B. HUNTER arm. 2,313,433

CIRCUIT CONTROLLING DEVICE 2 sheets sheet 2 Filed Jan. 10, 1941 3 l 4 46 5 MM 50 8o Mm @QWM M Patented May 4, 1943 UNITED STATES PATENT OFFICE Mekelburg,

Milwaukee, Wis.,

assignors to Cutler-Hammer, Inc.. Milwaukee, Wis., a cor-v poration of Delaware Application January 10, 1941, Serial No. 373,992

7 Claims.

This invention relates to circuit controlling devices, and more particularly to multi-pole controllers of the enclosed type.

The invention has among its objects to provide an improved multi-pole controller having a novel arc extinguishing structure for preventing arcs which are formed upon separation of the controller contacts under load conditions from intermingling and forming a shortcircuit between the several poles of the controller.

Another object is to provide a novel arc extinguishing structure for controllers of the aforesaid type which provides for rapid cooling of the arcs and exceedingly fast extinguishment thereof.

Another object is to provide an arc extinguishing structure which can be readily applied to enclosed multi-pole controllers without material modification of the controller, and without increasing the dimensions of the enclosing parts.

Another object is to provide an arc extinguishing structure for controllers of the aforesaid type including parts which are capable of being readily removed to render the contacts accessible for inspection or repair.

Another object is to provide an exceedingly compact and rugged arc extinguishing structure comprising parts which can be economically manufactured and readily assembled.

Various other objects and advantages of th invention will hereinafter appear.

The accompanying drawings illustrate an embodiment of the invention which will now be described, it being understood that various modifications may be made in the embodiment illus trated without departing from the spirit and scope of the appended claims.

Figure 1 is a side view of a controller embodying the invention, parts of the controller'being shown in section;

Fig. 2 is a top plan view of the controller, the stationary contact assembly shown in Fig. 1 being removed;

Figs. 3 and 4 are sectional views on lines 3- 3, and 44, respectively, of Fig. 2, and

Fig. 5 is a perspective view of one of the parts of the arc extinguishing structure shown in Figs. 1 and 2.

Referring to the drawings, the same illustrate an arc extinguishing str cture embodying the invention as applied to a three-pole reversing controller of the type disclosed in the patent to H. L. Mekelburg, No. 2.128.373, of August 30, 1938. Each pole of the controller includes a pair of movable bridging contacts I and 2 and a set of cooperating

stationary contacts

3, 4 and 5. The

several pairs of movable contacts I and 2 are carried by an insulating element 6 fixed to a rotatable operating shaft 1 and the several sets of

stationary contacts

3, 4 and 5 are mounted upon an insulating base 8. The above mentioned parts are carried by a frame 9 having a rear wall l0 and upwardly extending end walls II and I2, and said parts are enclosed by a U shaped cover l3 which is removably mounted upon said frame and has an insulating arc resisting lining l3 secured to the inner side thereof.

Insulating element 6 comprises a plurality of like molded insulating'sections M which are mounted side by side upon shaft 1 and are formed to provide axially spaced pairs of peripheral flanges I5, I6 and H. The opposing faces of each of said pairs of flanges are formed to provide cavities for receiving a pair; of bridging contacts I and 2, and said bridging contacts are yieldingly supported and held in assembled position within said cavities by springs l8 shown in Fig.3. Shaft I has an operating handle l9 fixed to one end thereof and the same is rotatably supported adjacent opposite ends within openings in the end walls II and I2 of frame 9.

Insulating element 6 and its associated operating shaft 1 are yieldingly held in an intermediate offposition (Fig. 3) by a star wheel mechanism 2| shown in Fig. 1 and are movable by handle IS in opposite directions out of such position into extreme on positions. In one extreme on position the several bridging contacts' lengage their associated stationary contacts' 3 and 4, and in the :other extreme on".v position the several bridging-contacts Z-engagetheir associated-stationary contacts 4 and '5. The several 'sets of stationary-

contacts

3, 4 and 5 are mounted'onthe" under side of insulating base 8,

and said'insulating base is secured to brackets 22 and 23'mounted on the'end walls ll and l2 In the respects above noted the controller is similar to that disclosed in the aforementioned I patent to H. L. Mekelburg. However, in accordance with the present invention" the controller is provided with two insulating barrier blocks 24 of like construction which form with insulating base 8 separate arc chambers for the stationary and movable contacts associated with each pole of the controller.

More'specifically, insulating base 8 is formed of molded arc resisting material and the under side thereof is provided with downwardly extending side walls 25, the lower edges of which are located in a horizontal plane in alignment with the axis of shaft 1. The under side of base 8 is also provided with end ribs 26 and two intermediate ribs 21 which extend between the side walls 25 to provide three spaced pockets 28 for receiving the pairs of flanges l5, l6 and I1 on element 6. The

ribs

26 and 21 are similarly shaped, and as shown in Fig. 4 each of the same is recessed as shown at 29 to clear element 6 and is provided with downwardly extending projections 36 which are located on opposite sides of said element. Also as shown in Fig. 4 the lower edges 3| of ribs 26 and 2] are flush with the lower edges of side walls 25.

The barrier blocks 24 are formed of molded heat resisting material and each is shaped to provide a vertical side wall 33' and a horizontal bottom Wall 34 having end ribs '35 and two intermediate ribs 36 extending therebetween. The end ribs 35 and intermediate ribs 36 are spaced "to align vertically with the end ribs 26 and intermediate ribs '21 on base 6 and the same form spaced pockets 38 in said blocks for receiving the three pairs of flanges l5, l6 and IT on element "6. The

ribs

35 and 36 are similarly shaped, each being concave as shown at '39 (Fig. 4') to clear element 6 and each having a horizontally disposed upper edge 46 which is flush with the upper edge of side wall '33. Side wall 33 has upwardly extending projections 4'! formed on op- I posite ends thereof for engaging opposite ends of base 8, and as shown in Fig. 5 the outer face of said side wall is provided with three vertically disposed pockets 42 in alignment with the pockets 38 on the opposite side of said wall. The under side of the horizontal bottom wall 3| is provided with a V-s'haped groove 43 and the upper edges of end ribs 35 are each provided with a V-shaped projection 44.

As shown in 'Figs. 3 and 4 the "barrier blocks 24 are held in assembled position against the under side of insulating base 8 with their horizontal bottom walls 34 in abutting relation by an elongated flatspring clip 45. Spring clip 45 is secured intermediate its ends to the rear wall I 0 of frame 9 and the same is indented adjacent opposite ends to provide projections 46 which engage within the grooves 4! in the under side of barrier blocks-24. With blocks 24 in assembled position the concave edges 39 of their associated ribs abut the projections 36 on the

rib

26 and 21 of insulating base 8. Also the V-shaped projections '44 on end ribs 35 of said barrier blocks engage within V notches formed on the under side of base 8 and the end projections 4| on said blocks engage opposite ends of said base to securely hold said blocks in assembled position.

In connection with the foregoing it should be noted that base 8 and barrier blocks 24 form a complete enclosure for element 6 and that the pockets 28 in said base and the pockets 38 "in said blocks form separate arcing chambers for theccntacts associated with each pole of the controller. Also it should be noted that the

ribs

26 and 21 on base 8 and the

ribs

35 and 36 on barrier blocks 24 form continuous barriers which extend inwardly beyond the pairs of flanges l5. l5 and I"! on element 6 to prevent flash-over of the arcs formed within said arcing chambers and also expansion of the arcs beyond opposite 'posed area to'provide for rapid cooling of the arcs formed therein. Also as is apparent from Fig. 3 each of the arcing chambers communicates on opposite sides with pockets 42 formed on the outer faces of barrier blocks 24 to provide for Venting of the gases produced by arcing within said chambers.

As is apparent, upon removal of cover l3 the barrier blocks 24 may be readily removed and replaced from opposite sides of frameQ, and upon removal of said barrier blocks the several bridging contacts I and 2 carried by element 6 are accessible for inspection or repair.

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

1. In a multi-pole controller, the combination with a plurality of contact sets, each including cooperating stationary and movable contacts, an osc'illatable insulating element having the movable contacts of said sets mounted thereon and spaced axially thereof, a stationary insulating base mounted to one side of said element and having the stationary contacts of said sets mounted thereon on the side adjacent said element for engagement by their associated movable contacts, and a pair of oppositely disposed insulating blocks located on opposite sides of said element and forming with said insulating base and said element separate arc extinguishin chambers for said sets of contacts.

2. In a multi-pole controller, in combination,

a supporting frame having a rear wall and for-' wardly extending end walls, a plurality of contact sets each including cooperating stationary and movable contacts, a rotatable insulating element having an operating shaft supported at opposite ends within openings in the end walls of said frame, said element having the movable contacts of said sets mounted thereon and spaced axially thereof, a stationary insulating base located to the front of said element and carried by the end walls of said frame, said base having the stationary contacts of said sets mounted upon the rear face thereof for engagement by their associated movable contacts and a pair of oppositely disposed insulating blocks arranged on opposite sides of said element and removably supported between the rear face of said "base and the rear wall of said frame, said insulating blocks forming with said insulating base and said element separate arc extinguishing chambers for said sets of contacts.

3. The combination with an insulating element having a plurality of pairs of bridging contacts mounted thereon and spaced axially thereof, an enclosing casing including a frame having said element rotatably mounted thereon, a stationary insulating base carried by said frame and located to one side of said element, said base having stationary contacts mounted thereon on the side adjacent said element to be selectively engaged by said pairs of bridging contacts, and a pair of insulating blocks of like form disposed in opposed relation on opposite sides of said element, said insulating bloclm forming with said base and said element separate arc extinguishing chambers for said pairs of bridging contacts and their associated stationary contacts.

4. In a multi-pole controller, the combination with a rotatable insulating element having a plurality of pairs of bridging contacts mounted thereon and spaced axially thereof, a stationary insulating base mounted to one side of said element, stationary contacts mounted upon said base for selective engagement by said bridging contacts in opposite extreme positions of said element, a pair of oppositely disposed insulating blocks arranged on opposite sides of said element and forming with said base a surrounding enclosure for said element, said insulating base and said blocks each being ribbed on the side adjacent said element to form with said element separate are extinguishing chambers for said pairs of bridging contacts and their associated stationary contacts.

5. In a multi-pole controller, the combination with a rotatable insulating element having a plurality of pairs of bridging contacts mounted thereon and spaced axially thereof, a stationary insulating base mounted to one side of said element, stationary contacts mounted upon said base for selective engagement by said bridging contacts in opposite extreme positions of said element, a pair of oppositely disposed insulating blocks arranged on opposite sides of said element and forming with said base a surrounding enclosure for said element, said insulating base and said blocks each having rib projections on the side adjacent said element to form separate arc extinguishing chambers for said pairs of bridging contacts and their associated stationary contacts, and said element having portions of reduced diameter for receiving the rib projections on said insulating base and said blocks.

6. In a multi-pole controller, the combination with a plurality of contact sets each including cooperating stationary and movable contacts, an oscillatable insulating element having the movable contacts of said sets mounted thereon and spaced axially thereof, a stationary insulating base mounted to one side of said element and having the stationary contacts of said sets mounted thereon on the side adjacent said element for engagement by their associated movable contacts, and a pair of oppositely disposed insulating blocks located on opposite sides of said element and forming with said insulating base and said element separate arc extinguishing chambers for said sets of contacts, said blocks being also recessed to provide vents which communicate with each of said chambers on opposite sides of said element.

7. In a multi-pole controller, in combination, an enclosing case including a frame having a rear wall, and forwardly extending end walls, a rotatable insulating element mounted within said casing and having an operating shaft supported at opposite ends within openings in the end walls of said frame, a plurality of pairs of bridging contacts mounted upon said element and spaced axially thereof, a stationary insulating base located to the front of said element and carried by the end walls of said frame, stationary contacts mounted upon said base to be selectively engaged by said bridging contacts in opposite extreme positions of said element, and a pair of insulating blocks of like form disposed in opposed relation on opposite sides of said element and engaging the rear face of said base, said blocks forming with said base and said element separate arc extinguishing chambers for said pairs of bridging contacts and their associated stationary contacts and being removable from opposite sides of said frame, and means associated with said frame for releasably holding said blocks in assembled position upon said base.

RICHARD B. HUNTER. HAROLD L. MEKELBURG.