US2420449A - Switching device - Google Patents

Description

May 13, 1947. H. E. SOMES SWITCHING DEVICE Filed June 6, 1944 2 Sheets-Sheet 1 fiowarfiifiomes 4 INVENTOR BY 71% ATTORNEY May 13, 1947.

H. E. SOMES I 2,420,449

SWITCHING DEVICE Filed June 6, 1944 2 Sheets-Sheet 2 HowafdESozhes 7o 2 INVENTORI ATTORNEY Patented May 13, 1947 SWITCHING DEVICE Howard E. Somes, Detroit, Mich., assignor, by mesne assignments, to The Budd Company, Philadelphia, Pa., a corporation of Pennsyl vania Application June 6, 1944, Serial No. 538,975

1 t This invention relates to switching devices and the like, and is directed particularly to devices for making and breaking a high-frequency circuit, and also to breaking such circuits in a transformer of the sliding-core type, wherein there is a likelihood of considerable arcing during breaking of the high-frequency circuit connections.

One of the objects of the present invention is to provide a new and improved yet simple arrangement for extinguishing the arc resulting from the breaking of the switch connections in a high-frequency circuit.

Another object is to provide a switching arrangement wherein movement of one of the switch connections is effective to compress a body of air or other fluid and direct the same under pressure to the switch connections to blow out the arc resulting from the breaking of such connections.

Another object is to provide a new and novel switching device particularly adaptable for use in high-frequency circuits.

A further object is to provide an improved transformer construction of the sliding-core type and having an improved arrangement for breaking the circuit connections to one of the transformer elements during movement of the sliding core.

With the above and other objects in view which will be apparent from the following description to those skilled in the art to which the invention appertains, the present invention consists of certain details of construction and combinations of parts to be hereinafter described with reference to the accompanying drawings and then claimed.

In the drawings, which illustrate a suitable embodiment of the invention;

Figure l is a longitudinal section of a transformer of the sliding-core type in which the improved arrangements of the present invention are incorporated, one of the transformer elements being shown in section and the other in elevation:

Figure 2 is an enlarged sectional view of the upper portion of the arrangement shown in Figure 1, the transformer elements being in uncouied relation and the inner element being shown in cross section, the section through the terminal connections for the outer transformer element being taken substantially on the line 22 of Figure 3;

Figure 3 is a side elevation of the terminal connections for the outermost transformer element;

and

Figure 4 is a transverse section taken approx mately on the line 4--4 of Figure l.

3 Claims. (Cl. 171119) Referring to the accompanying drawings in which like numerals refer to like parts throughout the several views, the electrical apparatus of the present invention embraces, for the purpose of illustration, a high-frequency alternating current transformer of the switching or sliding-core type having an inner primary element l0 and an outer annular secondary element II. The secondary element II is, as shown in detail in Figures 2 and 4, in the form of a unitary assembly comprising an annular longitudinally divided casing I2, a magnetic circuit element [3 and a hollow winding M. The casing I2 is provided at one end with a radially inwardly extending flange 15 which supports the annular circuit element l3. The circuit element I3 is comprised of a plurality of tapered radial laminations arranged in annular form. The annular plate I6 is secured by screws H to the open upper end of the casing l2 to securely clamp the laminated circuit element l3 against the supporting flange IS. The inner peripheral surface of the element I3 is recessed at l8 to receive the fiat-wound secondary coil l4, the coil being insulated from the walls of the recess l8, as shown in section in Figure 2. A number of laminations are remo ed at one portion of the annulus and replaced by a segmental insulating block l9, and the terminals 20 and 2| are turned outwardly to extend through this insulating block l9 and through openings 22 formed in the wall of the casing l2.

The terminal element generally designated 23 is mounted by screws 24 to one side of the casing l2 and includes a pair of cylindrical conductors 25 and 26, the conductor 25 fitting within and being insulated by an insulating sleeve 21 from the conductor 26, the conductor 25 projecting axially beyond the conductor 26. The conductor 25 is formed with a portion 28 having an aperture 29 therethrough, within which a passaged terminal connector 30 is secured. The conductor 26 is similarly formed with a portion 3| having an aperture 32 therethrough, within which a terminal connector 33 is secured. Secured by a screw 34 to the left side of the conductor 25, as viewed in Figure 2, is an insulating block 35 having portions 36 surrounding the connectors 30 x and 33 and the coil terminals 20 and 2|, respectively. The connectors 30 and 33 are provided with portions having a telescoping electrical connection with the terminals 20 and 2!, respec-- tively, and provide means to which suitable conduits (not shown) may be attached for circulating a cooling fluid through the secondary coil or winding [4. The insulating sleeve 21 and block 35 electrically insulate the conductors from each other and from the casing I2. The conductors 25 and 26 provide convenient terminals to which bus bars and the like may be attached.

By removing the screws 24, the entire terminal block assembly 23 may be removed, after which the casing halves upon removal of their securing means and the removal of the plate I! may be separated to pro 'ide access to the circuit element l3 and winding M. This condition exists when the secondary element assembly I l is removed from the assemblage to be hereinafter described.

The casing 12 is supported on and secured by screws 3! to a second annular casing 38 which in turn is supported on an annular ring 39 and secured thereto by screws 39a. The ring 39 is secured by screws 4! to a support 40, the support 48 having an opening 47! therethrough in coaxial relation with the casings l2 and 38.

The casing 38, similar to the casing 12, is provided with an internal flange 43 at its lower end and an annular removable plate 44 secured by screws 45 to the upper end of the casing 38. Positioned within the casing 38 and held in place by the flange 43 and the plate 44 is a second annular laminated magnetic circuit element 46 which is in alignment with and abuts the circuit element l3 to constitute an annular extension of the same.

The primary transformer element 18, which is concentrically arranged within the casings l2 and 38, is movable coaxially within the secondary element 13 and core extension 46 and includes a laminated magnetic core 41 similar to the core element I3 and is provided with a recess 48 in its internal face to receive the primary coilor winding 49.

Arranged within the core 41 is an annular supporting body 58 of non-conducting material, and supported at the ends of this body is an upper annular conductor connected through the body 50 with one end of the winding 49, and a lower cylindrical conductor 52 connected through the body 50 with the other end of the winding 49. Abutting the conductors 5i and 52 are an upper annular insulating ring 53 and a lower cylindrical insulator 54.

The core 4'! and the assemblage of the body 50 and insulators 53 and 54 rest upon an annular support 55 and disposed below the support 55 is an annular ring 56 which is clamped against the underside of the support 55 by bolts 51, the bolts extending downwardly through the insulator 53, the body 50 and insulator 54 and threaded into the ring 55. The annular plate 58 is seated on the insulator 53 in overlapping relation with the upper end of the core 47, and in order to clamp the core 4'! between the ring 55 and the plate 58,.certain of the bolts 51 (although not shown in detail in the drawings) extend through the plate 58. The upper ends of the last-mentioned bolts 57 are threaded and provided with a nut 59 instead of a head, as is the case of the bolts which extend only through the insulators 53 and 54 and the body 50. Obviously, however, other means may be provided for securing the plate 58 in clamping relation with respect to the core 41.

The entire primary element assembly 18 described is supported in its lowermost position through the ergagement of the ring 35 with an annular ring 60 disposed in the supporting opening 42 and secured by screws 62 to the underside of the annular element 39.

Mounted on the ring 60 by screws 82 is an annular housing 63 with which there is associated a depending fluid pressure cylinder and piston arrangement. The cylinder-and-plston arran ement comprises a cylinder 64, a piston 65 slidable therein having oppositely extending upper and lower piston rod extensions 86 which extend through the opposite cylinder sleeves 61 and 6B, the head 68 being rigidly secured to the lower open end of the housing 63. Suitable conduits 69a and 6912 are connected with the heads 58 and 61, respectively, for admitting fluid under pressure to and discharging the same from the opposite sides of the piston 65 for reciprocating the piston rods 65. The upper piston rod section 56 is provided with a flared portion 18 at its upper end which is secured by screws H to the ring 56.

In order to provide for cooling of the tubular primary winding 49, cooling fluid conduits 12 and 13 of insulating material are disposed within the tubular piston rod section 56, the conductor 12 being connected through a passageway 14 formed within the conductor 52 with the lower end of winding 49, and the other conductor 13 being connected through a passageway 15 in the body 50 with the other end of the winding 49, the passageway 15 appearing in broken outline in Figure 2.

The ring 55 has a relatively small clearance with the circuit element extension 46 whereby this ring, together with the casing 38, the annular member 39, the ring 50 and the housing 63 which is closed at its lower end by the cylinder head 68, forms a closed chamber 15.

As shown in Figures 1 and 2, the flared portion 10 of the upper piston rod section 56 is provided with a number of relatively small openings '11 therethrough. The space 1811 through the body 50 communicates with the space within the ring 56 and flared portion 10 through passages 18 formed in the cylindrical conductor 52 and insulator 54. p

The conductor 52 is provided with an extension 19 which extends upwardly within the body 58 in circumferentially spaced relation, and is provided at its upper end with an elongated annular conductor which extends well above the plate 58 and is axially split at its upper end to provide a plurality of resilient contacting fingers.

Supported on the upper end of the casing 12 and secured thereto by screws 8! is an annular housing 82 having an open upper end. This housing supports a bus bar arrangement which is comprised of inner and outer concentric tubular conductors 83 and 84 which are separated from each other by an insulating sleeve 85. The tubular conductors 83 and 84 are supported through an annular casting 88 secured by bolts 81 to the open upper end of the housing 82 and having an annular hub portion 88. To this end, the conductor 84 extends upwardly through the hub 88 and is provided with a flange 89 which is insulated from the lower end of the hub 88 by an annular insulating ring 90, the conductor 84 being further insulated from the hub 88 by an insulating sleeve 9!. The upper end of the conductor 94 is formed with a groove which receives a split ring 92, the split ring overlapping the sleeve 9| to support the conductor assembly described. In order to provide for this support, the insulating sleeve 91 is secured within the hub 88 against axial movement in any suitable manner. An annular insulating ring 92a surrounds the split ring 92 and assists in holding the ring 92 in the groove. Secured about the upper end of the conductor u is aiterminal connector 93. The conductor t: extends upwardly beyond the outer conductor 84, as shown in Figure 2-, and is provided with a suitable terminal connector 94. These connectors 93 and 94 are connected in practice with a source of high-frequency current. If desired, a cover housing 85 may bev provided and arranged to carry terminals 96 and 91 connectible (although not shown in the drawings) with the connectors 93 and 94, respectively, and in'tum connectible with the contactor 98 has substantially the same axial spacing from the conductor '84 as the contactor 80 has from the inner conductor 83.

In the operation of the apparatus described, the primary transformerr element Ill, when in uncoupled relation with the secondary element II, is in the lower position of Figure 2. In this position, the contactors 8|! and 98 are disconnected from the conductors 83 and 84, respectively. I

Upon the admission of fluid under pressure through the conduit 69b, the piston 65 through the upper piston rod section 56 moves the entire primary element assemblage in an upward direction, as viewed in the drawings. During this movement and immediately before the primary winding enters into coupled relation with the secondary winding Hi, the contactors 80 and 98 engage respectively with the conductors 83 and 84 to establish the circuit connections between the source of current and the primary winding 49. Continued movement of the primary element assemblage completes the coupling of the primary and secondary windings.

Upon admission of fluid, under pressure through the conduit 69a, such fluid enters the upper end of the cylinder 64 and moves the piston downwardly to uncouple the primary and secondary windings. During this downward movement, air is compressed within the circuit element extension 46 and the chamber 16, which air flows through the openings 11 in the upp r end of the piston rod 66 and upwardly through the passages 18 and exhausts between the resilient fingers of the contactors 80 and 98. Immediately following the uncoupling of the primary and secondary windings, the contactors 80 and 98 disengage from the conductors 83 and 84. The air compressed during the downward movement of the primary element assemblage and flowing upwardly between the contactor fingers with considerable velocity and blows out any arcs resulting from the breaking of the contacts.

The movement of the primary assemblage is preferably relatively rapid so that with the proper restriction of the passages 18 the air will be forced through such passages with sufficient velocity to extinguish arcing between the respective contactors and conductors upon initial disengagement of the same following uncoupling of the windings.

Although air has been described as the arc-ex- 6 tinguishing medium, other non-inflammable fluids may be utilized to equal advantage.

While the invention has been described in connection with the switching transformer, it will be obvious to those skilled in the art that the underlying principles thereof are equally as applicable to any switching arrangement, irrespective of functions other than switching functions.

I Various changes may be made in the detailed construction and arrangement of the parts described without departing from the spirit and substance of the invention, the scope of which is defined by the appended claims.

What is claimed is:

1. In an electrical switching device, concentric inner and outer transformer windings circumferentially spaced from each other, an annular casing surrounding and supporting said outer winding, a support for said inner winding circumferentially spaced inner and outer concentric contactors electrically connected with the opposite ends of said inner winding and coaxially supported by said support at one side thereof, means for moving said support coaxially of said outer winding to move said inner winding out 01' and into coupled relation with said outer winding, inner and outer concentric conductors insulated from each other, and means supporting said conductors in axial alignment with said support at said one side thereof, said inner and outer contactors in the coupled position of said inner winding being in overlapping electrical engagement with said inner and outer conductors respectively and being so disposed with respect to said conductors as to disengage therefrom upon movement of said inner winding out of coupled relation with said outer winding and to engage therewith upon initial movement of said inner winding into said coupled'relation.

2. In an electrical switching device, concentric inner and outer transformer windings circumferentially spaced from each other, an annular casing surrounding and supportin said outer winding, 9. support for said inner winding, contactor elements electrically connected with said inner winding and carried by said support at one end thereof, means for moving said support and winding supported thereby axially of said outer winding and into and out of coupled relation therewith, and a pair of current conductors, each electrically engageable with one of said contactor elements, said contactor elements being engaged ferentially spaced from each other, an annular casing surrounding and supporting said outer winding, 9. support for said inner winding, circumferentially spaced inner and outer concentric contactors electrically connected with the oppo site ends of said inner winding and coaxially supported by said support at one side thereof, means for moving said support coaxially of said outer winding to move said inner winding out of and into coupled relation with said oute winding, inner and outer concentric conductors insulated from each other, and means supporting said conductors in axial alignment with said support at said one side thereof, said inner and outer contactors in the coupled position of said inner winding being in overlapping electrical engagement with said inner and outer conductors respectively and being so disposed with respect to said conductors as to disengage therefrom upon movement of said inner winding out of coupled relation with said outer winding and to engage th r with upon initial movement of said inner winding into said coupled relation, said casing including an axially extending closed chamber, and said support having a restricted passageway there- HOWARD E. SOMES.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 2,223,902 Somes Dec. 3, 1940 1,790,746 Fischer Feb. 3, 1931 1,336,343 Arndt Jan. 25, 1921

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