US1838664A

US1838664A - Circuit breaker

Info

Publication number: US1838664A
Application number: US137559A
Authority: US
Inventors: Dubilier William
Original assignee: Individual
Current assignee: Individual
Priority date: 1926-09-24
Filing date: 1926-09-24
Publication date: 1931-12-29
Anticipated expiration: 1948-12-29

Description

Dec. 29, 19341. W DUB|L|ER 1,838,664

CIRCUIT BREAKER original Filed sept. 24, 192e 2 Sheets-Sheet 1 Dec. 29, 1931. w. DUBILIER 1,838,664

CIRCUIT BREAKER original Filed spi. 24, 192e 2 sheets-sheet 2 \6Z l QZ, 62

62, Inl/erm. 95. Ej Uhlham uluher y or -less diag'rammatically arrangements for' Patented Dec. 29, 1931 WILLIAMQDUBILIER, OFYNEW ROCHELLE, NEW YORK CIRCUIT imEAxEn Application led September 24, 192, Serial No. 137,559. Renewed yMay 19, 1931.

This inventin relates to controlling devices; particularly devices for interrupting or varying, if desired,.the current of an electric circuit.

An object of my invention is to provide a controllingdevice that will be low in cost and relatively small size, and yet capable of operating effectively to open an electric circuit, or regulate a resistance therein so as to alter the amount of current flowing, as may be needed.

Further objects and advantages of the invention are set forth in the following description, taken with the drawings, which show several forms in which my invention is embodied. But the disclosure is illustrative only; and I may vary the constructions actually shown to the full extent which is consistent with the broad meanings of the terms in which the appended claims are expressed.

On said drawingsy Figures 1 and 2 are longitudinal sections of two separate forms of my invention for use ,asl circuit-breakers Figure 3 is adetail showing a modification of one of the parts; v

Figure 4 is a longitudinal section and Figure 5 a plan view of `a device for varying the resistance of a circuit; o

Figure 6 shows in perspective a container for the parts of the device shown in Figs.4 and 5; Y

y Figure 7 is a sectional view of another form of circuit breaker; v 1 Figures 8, 9, 10, 11, and 12 show more breaking a circuit by means of a heated wire, and i i Figures 13 and 14 show similarly apparatus to reduce or increase resistance in a circuit.

The same numerals identify the same parts.

Figure 1 shows a controlling de vice designed to open anelectric circuit under predetermined conditions. It-comprises a plug consisting of an upper part 1 of insulation and a lower part of conducting material indicated by the numeral 2. In practice the part -1 will be the front and the part 2 the rear, since the part 2 is inserted into a socket adapted to receive and mount the plug. The

part 1 has the form of a cup, closed at the bottom 3 except for a central opening; and the part 2 is a threaded metal shell made fast to the rim of the cup 1 at one end, and carrying at the other a closure disk 4. Both the cup and the shell are preferably cylindrical.

In the exterior surface around the rim of the mouth of the cup I may form a groove, and the edge of they shell 2 may be turned over as at 5 to enter this groove tightly, and the cup and shell are thus secured together. The opposite endv of the shell has its edge turned over inward as at 6 to engage the periphery of the disk 4; and between the threads on the shell 2, conveniently provided by spinning or lrolling or in any other suitable fashion, and the inturned edge 6, the disk 4 is held Ifirmly in place. The disk is of insulation; but carries on its outer face a fixed contact 7 secured by a rivet 8 passing through the disk 4 and fas- 70 tening to the inner face thereof a metal leaf spring 9. This spring is bowed away from the disk, presenting its convex side thereto; and it is engaged by the ends of a smaller metallic leaf spring 10. made fast at its center to a contact of carbon Aor other conducting X material 11 as by a rivet 12. The concave side of the spring 10 is toward the-disk 4, and the ends of the spring 10 pass through openings in the spring 9 and are turned over to prevent 80 the ends of the spring 10 from becoming disengaged from the spring 9. 'At the same time the ends of the spring 10 may have some play if desired in the openings of the spring 9 which receive them; so that pressure on'the 85 contact 11 can to some extent flatten the springs 9 and 10. Opposed to the fixed contact 11 is a movable contact of the same material 11, held by a rivet 12 to another metal spring 10, secured in the sameway to anothermetal spring'9, which is fastened by a screw or rivet 8 to theend of a metallic stem 13. The spring contact 9 and springlO attached to the stem 13 are arranged with respect tothe stem in the same manner as the and the second spring 10 has its convex face 100 presented in the same direction. Hence when the stem 13 is moved towards the ydisk 4, the contacts 9 and 11 can be made to come together, the contacts 11 coming together first by virtue of their closer proximity to each other than contacts 9.

Inside the mouth of the cup 1 is a' fixed closuredisk 14 having a central opening 15 for the stem 13, and the bottom 3 of the cup, which is the front end of the plug has a similar opening 16. The interior of the cup is thus separated from the interior of the shell, and the inside of the shell 2 constitutes a chamber wherein the springs 9 and 10 and the contacts 11 are located. The stem 13 has a collar or washer 17 thereon abutting against a stop 18, and inside the cup is a s ring or resilient element 19 between this colar and the disk 14. This spring tends to separate the contacts 11. Normally, however, the contacts are held in engagement with each other by a thermostatic element 20 having a latch 21 to engage the collar 17, and encircled by a resistance or heating coil 22. This coil is connected to the stem 13 at one end, and extends through the cup l to unite -with the shell 2 at the other. The element 20 is affixed in any suitable way to the inside of the cup, as by fastening it on the closure 14. It has the form of a strip made of layers of brass and steel, or other metals of different coeiicients of expansion. Such strips are well known and generally referred to under the name of bi' metal. Hence, vin operation, if the stem is pushed in against the spring 19, the contacts 11 will be forced into engagement with each other; and the springs 9 and 10 may yield and permit the contacts 11 to come together squarely and engage evenly over the entire surfaces. With the contacts 11 in such relation, the latch 21 will hold the stem and keep the contacts from separating. But if too much current owsthrough the coil 22, the heating effect of the current on the strip 20 will cause .this strip to bend away from the stem. pulling back the latch 21 to release the collar 17 and a'llow the stem to move upward under the force of the spring 19. Thus the circuit through the contacts 11 will be broken. Of course strip 2O will have the layer which expands the more on heating disposed on the side towards the stem, so as to bend awa from it when the latch 21 is to be pulled back, as with an excess of current. The upper end of the latch may be bevelled, so that the collar 17 will push this latch resiliently to one side as the stem is forced inward of the plug.

This type of controlling device is adapted for circuits on power lines instead of the usual kind of fuse which burns out 011 excess current. The circuit is through the threaded shell of the socket which receives the shell 2; the shell 2, coil 22, stem 13, contacts 11, contact 7 and finally the central contact of the fuse socket to the other conductor joined to the fuse socket. This plug will not be destroyed by excess current, but will only inter rupt the circuit. It can then be reset merely by pushing in the stem 13, and the circuit restored. At the same time the cost of manufacture is comparatively little. The contacts 1l may be of carbon, and will absorb the heat of the spark when the circuit opens, since they are the last to separate.

Figure 2 shows another form of my invention, very similar to that just described, except that instead of the small carbon contacts 11, two blocks orvdisks 11 and 11 of carbon or other material arc used. One of these rests on a metal plate 23` turned up around its rim at 24 to grip the block ll. This plate 23 is disposed against the inner face of the disk 4, and has a boss 25 which projects through a central aperture in the disk to constitute the outer central Contact of the plug. In this boss is a spring 26 encircling a stem 27 carrying a head 28, the stem and head, with the upper part of the spring being within a central opening 29 of the block 11 The other block 11 is carried by the stem 13. This stem has a head 28 on its inner end; and the block 11 on the stem has an opening 29 with an inside shoulder 31, against which is an insulating gasket or packing 32. The head 28 is engaged by this gasket, so that as the stem rises, the block 11 thereon rises with it. On said lock may be put several perforated disks 33 of similar material, surrounding the stem 13; and on top of these disks 33 is an elliptical spring 9', pressing with one side against these disks 33. Both sides or halves of this spring 9 encircles the stem 13, the lower half loosely, but the upper half is secured on the stem between two fixed collars 34. In the cup is an electromagnet coil 35, with a plunger 36 of magnetic materiall impelled outward by a sprmg 37 in the coil 35. This coil is joined to the stem 13 and to the shell 2 by a wire 22". To bring the contacts 11 and 11 together, the stem 13 is forced inward to enable the plunger 36 to engage the upper end of a rib or a stop 18 on the stem, and thus the plunger acts as a catch to hold the contacts l1 and l1 in engagement. In this condition, the plug will have the head 28 pressing resiliently against the head 28 and the upper block y 11 held by the spring 9 acting through the disks 33 firmly against the lower block 11. When sufficient current flows through the coil 35 to overcome the spring 37, the catch 36 is pulled back, and the stem released. The stem is then moved up by the spring 9. I may bevel the outer end. of the catch, so that, when the stem 13 is forced inward, the stop 18 Will push back the catch, but the spring 37 will immediately return it over the top of the catch. Of course the catch 36 must be polyg onal or otherwise to engage the inside of the coil 35 so that it will not turn in same. This plug may act so that when the coil 35 retracts the catch 36 the compressed spring 9 will impel the stem 13 upward with a slight bound, rst separating the

heads

28 and 28 and then lifting the upper block 11 and blocks 33. Then before the stem 13 and the block thereon can again drop to bring the heads 28 and28 and the blocks 11 and 11 .togetheragaim the spring 37 acts to force out the catch136, because the magnet 35 is nowdeenergizedand this catch projects under the stop 18 and the stem and the parts carried thereby remain in raised position. Such action is important when the plug is used with the shell 2 lowermost, or horizontally, while if the shell 2 is uppermost, gravity will always keep the contacts 11 and 11" apart after the coil acts. The current flows through the stem 13 and heads 28 and 28 and the contacts 11 and 11, which are of carbon, for example, absorb the spark when the plug opens the circuit. The moment the stem is released, the pressure on the blocks or resistance elements 11', 11" and 33 is reduced, and the resistance through them increased. The arc is thus more quickly extinguished.

Figure 3 shows how in place of a resistance coil to heat the thermostatic element 20 I can use a heating block 38 which is preferably of carbon. This block 38 is secured to the strip by bands 39. On the block 38 is put a conductive plate to which a conductor is attached. The bands 39 may be of metal, and between the bands and the plate 40 is a plate or sheet of insulation 41. Also, block 38 should preferably not be so wide as the face of the strip, which is shown in edge view,

so that the sides of the block and the bands fore.

are spaced apart.r Then current must flow to the strip through the block 38 and not through the bands 39. When the block grows warm, the latch 21 will be pulled back as be- The strip 20 may be set up on any suitable support in the plug, as at 14.

Figures. 4, 5, and 6 show a controllingdevice for gradually reducing the current in a circuit and then opening the circuit altogether. Here I show a trough-shaped metal container 42, open at the bottom, with ledges or shelves 43 inside at each end, and extended extremities 44. Inside this container is a resistance element of carbon or other substance 45, resting at its ends on the shelves 43. It is flush with the upper edges of the container and ends 44; and in its upper surface is a depression 46.YA Insulating strips 47 separate the. sides of the carbon 45 from the sides of thecontainer 42. Movable contacts, such as brushes 48, which may be attached to the conductorsof a circuit, may engage the ends 44, and thus put the whole length of the carbon element 45 out of operation, the circuit being closed through the container 42. As the bushes move upon the carbon towards each other and out of Contact with the container, the carbon member 45 comes into the circuit, introducing resistance, and decreas-` ing the current. The portion of the element 45 in circuit increases as the brushes appreach, because current\must flow from one brush to the adjacent end of the container, then through the container to the other end by way of the carbon element again to the other brush to the opposite side of the circuit. When the brushes reach the middle of i gaging an opening in the support. This element 50 may be prismatic in shape. It is engaged'by a V-shaped contact 52, with curledup edges 53, attached to a metallic rod 54.

This rod may carry a split cylinder 55, the

edges of which press on the sides of the contact 52. The lower end of the rod 54 may be thinned to provide a shoulder against which the cylinder is placed, the cylinder having an opening in its side to give passage to the thin end of the rod. The parts are all seen in edge view in Figure 7. When one end of a circuit is connected to the element 5() and the other to the contact 52, then the resistance will be least and current greatest when the contact 52 is forced down to engage the whole side surface of the element 50 and touch plate 49. As the rod 54 is lifted, the member 50 is included in the circuit more and more, increasing the resistance and reducing the current.

In Figure 8, I show at 56 a support bearing a flexible metallic member 57 carrying a movable contact 58. Adjacent the contact 58 is a fixed contact 59. Between two fixed suports 60 is a wire or conductor 61, making a hermal member the length of which will increase upon heating. To the wire -61Y are connected the conductors of a circuit 62 and wires 63 unite the ends of the wire 61 to the member 57 and contact'59. A link 62 of insulating material unites the wire 61 and member 57. The member 57 has a normal set to move the contact 58 towards the contact 59, but the link 62 holds it back. When the wire 61 heats and lengthens, the spring member 57 is allowed to move the contact 58 against the contact 59 and short-circuit the wire 61. This device may be used for flashing lamps. When the wire 61 is shortcircuited, it cools and contracts, pulling on `the member 67 to break the circuit. Hence 63 will intermittently light up and go out.

Figure 9 illustrates the same device, with a longer wire 61, passing over idler pulleys 64 between the conductive supports 60. rIhis longer hot wire gives more expansion.

In Figure 10, the supports are mounted on an insulating member or cover 65, and the middle of the wire 61 is connected to the member 65 by a spring 66. At 67 is a rod mounted to slide in a bearing 68. Encircling this rod is a spring 69, between one of the bearings 68 and a fixed collar 70. A latch 71, on a pivot 72, engages the collar and holds the rod 67 in position to force the member 57 to hold the contact 58 against the Contact 59, the spring 69 now being compressed. Another latch or lever 71, also on a pivot 72 is connected by a link 74 at one end to the lever 71 between the catch 73 and pivot 72 and a similar link is connected to the second lever 71 between its ends, and to the wire 61 adjacent the point of attachment of the spring 66. The tension of the wire 61 offsets the spring 66, but as the wire heats and gets longer, the spring. 66 can lift the levers 71 and spring 69 then acts to move the rod 67 and release the member 57 to open the circuit. The wire 61 then cools, and the operator can again close the circuit by pushing on a knob at the end of rod 67.

Figure 11 shows a fixed contact 59 con nected to a bellcrank lever 75 on a pivot 76,

vand to one side of the circuit. The opposite side of the circuit is joined to a sliding contact 58', one end of which is engaged by a hook 73 on a latch 71, mounted on a pivot 72. A link 74 of insulating material joins the levers 71V and 75 together. The end of the lever 71 is connected to a spring 77 attached to a fixed point, this lever having a projection 78 of insulation to which the spring is affixed; Contact 58 is mounted on a rod 79, affixed to a support 80, and carries a spring 81 to draw back the contact 58 and open the circuit. The contact 58 may have a bore 82 in which the 4rod 79 is received, so that the contact slides on the rod. Heating of the wire 61 results in lifting the catch 71.to re lease the contact 58.

In Figure 12 the hot wire 61 is enclosed in a tubular sleeve or housing 83, with ends 84, all of insulation. The ends of wire 61 pass through the ends 84, and a link 74, joined to the middle of the wire 61 passes through an opening in the sleeve 83V and is connected to a cord 85 passing over an idler pulley 86. The other end of this cord is attached to a fiexible member 87 fixed to a support 88, and a spring 89 attached to the end of this support and to a fixed point tends to pull the member` 87 and cord 85 and keep the cord taut. Oh a rod 67 sliding in bearings 68 is av contact 90, and a fixed contact in proximity thereto is joined by a wire 91 to one end of the wire 61. The pulley 86 is mounted on a journal or pivot 72 and rigid with the pulley is a. latch 71, having a hook 73 to engage a collar 70 on the metallic rod 67, a spring 69 encircling this rod as in Figure 10 between the collar 70 and one of the bearings 68. This bearing may be joined to one side of the circuit and the other end of the wire 61 to the remaining side. `When the wire 61 heats and expands, the spring 89 can pull the member 87 to turn the pulley 86, moving the latch 71 torelease the collar 7 O and rod 67 so that the spring 69 can cause the contact 90 to move away from the contact at the end ofV conductor 91, and opens the circuit.

Figures 18 and 14 show a row or pile of carbon or other resistance disks or blocks 31 between end members or plates 92. The ends of each row or pile is joined to a circuit by conductors 62', and the other end is pressed upon by a point 98 on a spring or flexible member 94, fixed to a support 95. The member 98 is also connected through a thermal member or hot wire 61 to another circuit by conductors 62. In Figure 13, heating up of wire 61 allows the member 94 to compress the elements 81 and reduce resistance and increase current; while in Figure 14, the heating of the wire 61 produces the opposite effect.

Having described my invention, what I believe to be new and desire to secure and protect by Letters Patent of the United States is 1. A fuse-socket device for an electric circuit comprising a fixed contact, a movable contact, a thermal member to hold said contacts in engagement, and an element to separate the contacts when released by said thermal member, said contacts being adapted to introduce resistance into the circuit while moving away from each other.

2. A fuse-socket device comprising a yielding Contact, a resistance element associated therewith, a movable contact comprising a stem, resistance element associated with this Contact, a spring to hold said contacts and said elements in engagement, and a heating coil and thermal member to release the stem and allow the contacts and resistance ele ments to separate.

2. A circuit breaker enclosed in a socket plug comprising relatively movable contacts part of which are of relatively greater resistance and arranged to open later than the others. t

4. A fuse-socket device comprising metallic fixed and movable contacts, and fixed and movable contacts of carbon mounted to separate after the metallic contacts.

5. A fuse-socket device comprising metallic iixed and movable contacts, and. fixed and movable contacts of carbon mounted to separate after the metallic contacts, at least one of the metallic contacts being yeldable.l n

6. In an electric circuit, a plug type breaker device comprising a pair of vnormally engaged contacts in said circuit, a second pair of contacts in shunt with said first pair of contacts and bi-metallic .means associated vwith said circuit for controlling the operation of both pairs of said contacts in a predetermined order.

7. In an electric circuit, a plug type breaker device\comprising a pair of normally engaged contacts in said circuit, a second pair of contacts in shunt with said first pair of contacts, a latch device holding said contacts in engagement yand a bi-metallic means associated with th`e\ circuit for operating said latch device to control the operation of both aidpairs of contacts in a predetermined orer. v v

8. In an electric circuit, a plug type breaker device comprising a pair of flexible contacts connected in said circuit, a spring device operating to cause said contacts to disengage, a latch device for holding said contacts in engagement against the action of saidv spring and `loi-metallic means associated with said circuit for operating said latched device to permit said springs to operate said contacts into disengagement. v A

9. In an electric circuit, a plug type breaker device comprising a fixed contact, a movable contact, means for normally urging said contacts into disengaged condition, a latch device for normally holding said contacts inlto engagement against the operation of said last mentioned means, a bi-metallic means associated with said electric circuit operating said latch into a non-operating position whereby said first mentioned means is operative to operate the contacts into disengaged condition and means for varying the resistance of said circuit as said contacts are opened.

10. In an electric circuit, a plug type breaker device comprising a stem, an inflexible contact and a flexible contact carried by said stem, an inflexible contact and a flexible contact positioned opposite said first mentioned contacts respectively and arranged to be engaged thereby, said flexible contacts being l arranged to disengage before said inflexible contacts disengage.

11. In an electric circuit, a plug type breaker device comprisng a stem, an inflexible contact and a flexible contact carried by said stem, an inflexible contact and a flexible contact positioned opposite said first mentioned contacts respectively-and arranged to be engaged thereby, said `flexible contacts being arranged to disengage before said inflexible contacts disengage, means normally urging said stem to carry said first mentioned contacts from engagement with said second;` mentioned contacts, a latch device holding said stem in 4operative position in which said contacts are in engagement and a thermal responsive means for operating said latch device from holding said stem whereby said first mentioned means operates said stemv to disengage said contacts.

12. In an electric circuit, a fuse plug t pe breaker device comprising a stem, an in exible contact and a flexible contact carried by said stemfan inflexible contact and a flexible contact positioned opposite said first mentioned contacts respectively and arranged to be engaged thereby, said flexible contacts being arranged to disengage before said inflexible contacts disengage, means normally urging said stem to carry said first mentioned contacts from engagement with said second mentionedI contacts, a latch device holding said stem in operative position in which said contacts are in engagement and a bi-metallic responsive means for operating said latch device from holding said stem whereby. said first mentioned means operates said stem to disengage said contacts.

13. In an electric circuit, av plug type breaker device comprising a stem, an inflexible contact and a flexible contact carried by said stem, contacting means positioned opposite the said contacts and arranged to be engaged thereby, said flexible contact being `arranged to disengage from said contacting means before said inflexible contact disengagesv therefrom.

In testimony whereof I aflix my signature.

WILLIAM DUBILIER.