US1417940A - Service switch - Google Patents

Service switch Download PDF

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US1417940A
US1417940A US1417940DA US1417940A US 1417940 A US1417940 A US 1417940A US 1417940D A US1417940D A US 1417940DA US 1417940 A US1417940 A US 1417940A
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slide
hub
spindle
open
closed
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    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01HELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H19/00Switches operated by an operating part which is rotatable about a longitudinal axis thereof and which is acted upon directly by a solid body external to the switch, e.g. by a hand
    • H01H19/54Switches operated by an operating part which is rotatable about a longitudinal axis thereof and which is acted upon directly by a solid body external to the switch, e.g. by a hand the operating part having at least five or an unspecified number of operative positions
    • H01H19/60Angularly-movable actuating part carrying no contacts
    • H01H19/635Contacts actuated by rectilinearly-movable member linked to operating part, e.g. by pin and slot

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  • This invention relates to electrical service switches, and has for its object to provide certain improvements therein to ensure an accurate engagement and disengagement of the contact members, andalso to secure a quick break upon the manipulation of the operating handle.
  • the invention comprises a switch having certain features of construction and arrangement which are villustrated upon the' accompanying drawings, described in the following specification and the appended claims.
  • Figure 1 represents in front elevation a switch mechanism embodying the invention, the cover vof the case being removed to show the interior.
  • Figure 2 is a similar view illustrating the slide in its closed position, being in part a section onthe line 2-2 of Figure 3.
  • Figure 3 represents a longitudinal section through the switch. f f
  • Figure 4 shows in detail the construction of the mechanism for moving the slide.
  • Figures 5 and 6 illustrate the operation of the mechanism, the dilferent positions of the parts being shown in dotted lines. These two views areas though taken on the line 2.-2 of Figure 3.
  • FIG. 7 shows in detail one of the stationary contacts of the switch.
  • the switch which l have illustrated as an embodiment of the invention, is ininany of its features identical with the service switch illustrated in the application of John A. Jessen, Serial No. 200,591, filed November 6, 1917, to which reference may be had for a detailed description of the parts tol which reference hereinafter will be but do, as will be explained, they quickly move 0f course it will be understood that theV brieiiy made.
  • the mechanism is located within a case pointed vout in cated as a whole at 10, and the removable Y cover is indicated at 11, being provided with thelaterally sliding door 12 (see Figure 3).
  • a removable plate 13 Secured to the bottom of the box there is a removable plate 13 to which are attached the two blocks 14, 14, of slate, fiber or other insulating material.
  • I have illustrated the stationary contacts as being of the spring-'clip variety to engage knife members between the jaws thereof.
  • a slide comprising a plate 16 and a bloclr 161 of insulating material, upon which are secured the movable switch knife members 17, 17. These memc prevent access to the current-carrying contacts 15, the slide is provided with the parallel side walls 19 of liber or otherinsulating material and with a cross wall 20 of the same material. The walls 19, 19, are spaced no further apart than the width of the opening which is closed by the sliding door 12.
  • the plate 13 is provided with upturned marginal portions 21 which are turned inwardly as at22 (see Figure 4) to form guideways for vthe down-turned side marginal portions 23 of the plate 16 which constitutes a portion of the slide.
  • the slide is normally held in its open position to the right, as shown in Figures 1 and 3, by springs 24, 24, which have their rear ends attached to the plate 13 and their front ends attached to the plate 16 of the slide.
  • the slide is moved to closed position against the tension of the springs, and, as soon as the springs are able so to movement of the slide will now be explained.
  • It comprises a handle lever 25, having upon its end a knob 125.
  • the hub of the handle is secured upon the upper end of a spindle E26r which is journaled in the box and extends through the cover thereot so that the handle may be secured upon its projectingr end as by a screw 22T and washer 12T.
  • crank arm 33 is connected with a crank arm 33, as illustrated in Figure 3, and they are capable ot a predetermined rotative movement one in relation to the other.
  • Said crank arm has an axially ⁇ extended hub 27 provided with an axial socket 28 at its upper endfto 'receive the lower end Q9 o't' the spindle 26.
  • the hub is stepped at its lower end in an aperture in the base plate 123, and it is also mounted to rotate in an aperture in a plate 30 secured to an upright 3l attached to the upturned end ot said plate 13.
  • the spindle 26 in addition to being; journaled at its lower end in the hub 2T, is journaled in an inwardly projecting bracket 32formed by bending ⁇ the upper end of the upright 31, and said spindle is also journaled in the hole in the cover through which its upper portion projects.
  • To the crank arm is pivoted one end ot an elongated curved link or connection etby a pivot pin 35 to constitute therewith a toggle which may be brought into two dead-center positions alternately.
  • the other end ot the link 34 is ⁇ pivoted b v a rivet 537 to a lug 3G attached to the under side of the slide plate 1G, as shown in Figure
  • the crank arm 33 may be rotated through an arc o't a little greater than 180.0 until it has ⁇ inst past a dead-center position as shown in Figure 5, the link 3l being' curved to permit this movement. Then the hub has been rotated to this position, it will be seen that the slide is locked by the toggle in its closed position with Jthe movable contact 17 in mechanical and electrical Contact with the stationarg1 contacts 15.
  • the springs 2d By rotating ⁇ the section or hub 27 anti-clockwise until ⁇ the crank arm has been swung out of its said dead-center-position1 the springs 2d quickly move the slide to its open position, and this will occur upon release el" crank 33 during ⁇ any part oi its movement clockwise until the crank arm has actually reached a deadcenter position when the toggles are straight and hence. in the second ilead-center position, the slide is locked in its open position with the contacts separated.
  • the hub 2T is provided with two separated stops or shoulders 38, 138, which are 'formed bv cut ⁇ ting, ⁇ away a portion o'f the upper end thereot and the spindle is provided with a lugl or pin 39 which mayv pla)v between these two stops.
  • a coiled spring Ll() encircles the spindle 26, one end thereof beingl secured in a hole L L1 in the upper end o't' the hub 27, and the other end olf the spring bearing against a lug' or projection e2 extending radially trom the spindle QG.
  • This springl exerts its tension upon the spindle QG to rotate it clockwise so as normally to hold the stop pin 3f) iu engagement with the stop 3S on the hub 2G.
  • I preferably provide interlocking mechanism to prevent the handle from being operated when the door is opened and to prevent the door from being opened when the handle is in its closed position, that is, when the switchrhas been moved to closed position.
  • the upper part of the handle is provided with the member 43 for cooperation with the rib 44 on the door.' I have not shown these parts in detail as they are illustrated and described in the application hereinbefore referred to.
  • the member t3 is a disk having a flat face 43 on its periphery which engages the flange or rib la ⁇ extending inwardly along the lower edge of the door when the latter is open to hold the rock shaft against rotative movement and thus to lock the slide or carrier in open position.
  • the rock shaft is rotated to move the carrier to closed position, an arcuate portion of the member 43 moves into the path of the Hange or rib, as shown in dotted lines in Figure 3, and thus locks the door in closed position.
  • a service switch comprising a slide carrying movable contacts, a toggle including a straight link and a curved link arranged to move said slide in opposite directions to closed and open positions respectively,and, when in dead-center positions, to lock said slide in said open and closed positions, spring mechanism for automatically moving said slide to open position, an oscillatory member, and lost-motion means connecting said toggle and said member whereby said slide is operated in one direction to closedr and locked position by said member and said toggle, and said slide may be operated in the other direction to open and locked position by said spring mechanism independently of said member.
  • a service switch comprising a slide carrying movable contacts, a toggle including a straight link and a curved link are ranged to move said slide in opposite directions to closed and open positions respectively,v and when in dead center positions to lock said slide in said open and closed positions, spring mechanism for automatically moving said slide to open position, an oscillatory member, lost motion means connecting said toggle and said member, whereby said slide is operated in one direction to closed and locked position by said member and said toggle, and said slide may be operated in the other direction to open andlocked position by said spring mechanism independently of said member, and a spring normally holding said member at one limit of motion relative to said lost motion means.
  • a service switch comprising stationary contacts, a slide arranged between said stationary contacts and having laterally projecting movable contacts, spring mechanism for moving said slide to open position, a crank arm, a curved link connecting said crank arm to said slide and having a jonrnaled hub, said link and arm constituting a toggle adapted in its dead-center positions to lock said slide in its closed and open positions respectively, and means for operating said crank comprising a spindle journaled in said hub, a handle thereon, coacting stops between ⁇ the spindle and the hub of the crank arm to permit a limited play between them. and a spring coiled about said spindle and having one end connected to said spindle and the other end connected to said hub.
  • a service switch comprising a closed box or case, guides stationarily supported within the case, a slide adapted to reciprocate on said guides, laterally-projecting movable contacts on said slide, stationary contacts between which the slide is located and with and from which the movable contacts may be connected and disconnected, spring mechanism 'for moving said slide to open position, a hub journaled .in stationaryv bearings in the box and having an arm, a curved link connecting the arm with said slide, said link and arm constituting a toggle which in dead-center positions locks the slide in its open and closed positions respectively, a rock-shaft projecting through the front wall oi the box, said shaft and hub having a lug ⁇ and spaced stops, a coiled spring having' one end secured to the shaft and the other end secured to the hub, and a handle located on said shalt outside the liront Wall or the case, substantially as and for the purpose set forth.
  • a service switch comprising ⁇ a closed box or case, guides stationarilT supported within the case, a slide adapted to reciprocate on said guides, laterally-projecting .movable contacts on said slide, a iusc on the front face of said slide in electrical engagement with said contacts, a movable door ilor said case positioned in front of said fuse, stationary contacts between which the slide is located and with and from which the movable contacts may be connected and disconnected, spring mechanism for moving; ⁇ said slide to open position, a hub jour naled in stationary bearings in the box and having ⁇ an arm, a curved link connecting the arm with said slide, said link and arm constituting a toggle which in dead center positions locks the slide in its open and closed positions respectively, a rock shaft projectin b through the front Wall of the box, said shaft and hub having a lug and spaced stops. a coiled spring having, ⁇ one end secured to the shaft and the other end secured to the hub, and cooperating members on said hub and door for preventing the opening of said door except when

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Description

G. E. PALMER. sEHv'lcE SWITCH.
APPL'lcATloN FILED APR. 12. 191s.
Patented. May 30,' 1922.
2 sHEETs-SHEET L.
l EUR @www G.,E. PALMER.
SERVICE SWITCH.
APPLICATION HLEn MR. 12.. 1918.
Patented May 30, 1922.
,2 SHEETS-SHEET 2.
Illini EN., MY
fill
Mya
'UNITED STATES PATENT orricr..
GRANVILLE E. PALMER, OIE' BOSTON, MASSACHUSETTS, ASSIGNOR TO PALMER ELECTRIC & MANUFACTURING COMPANY, F BOSTON, MASSACHUSETTS, A
CORPORATION OF MAINE.
sERvicE SWITCH.
Specification of Letters Patent. Patentgd lvay 30, 1922.
Application filed. April 12, 1918. `Serial No. 228,102.
.To al@ whom t may concern:
Be it known that I, GRANVILLE E. PALMER,
n a citizen of the United States, residing at Boston, in the county of Suolk and State of Massachusetts, have invented new and useful improvements in ServiceSwitches, of which the following is a specification.
This invention relates to electrical service switches, and has for its object to provide certain improvements therein to ensure an accurate engagement and disengagement of the contact members, andalso to secure a quick break upon the manipulation of the operating handle. y
The invention comprises a switch having certain features of construction and arrangement which are villustrated upon the' accompanying drawings, described in the following specification and the appended claims.
Referring to the drawings-f l Figure 1 represents in front elevation a switch mechanism embodying the invention, the cover vof the case being removed to show the interior.
Figure 2 is a similar view illustrating the slide in its closed position, being in part a section onthe line 2-2 of Figure 3.
Figure 3 represents a longitudinal section through the switch. f f
Figure 4 shows in detail the construction of the mechanism for moving the slide.
Figures 5 and 6 illustrate the operation of the mechanism, the dilferent positions of the parts being shown in dotted lines. These two views areas though taken on the line 2.-2 of Figure 3.
Figure 7 shows in detail one of the stationary contacts of the switch.
The switch, which l have illustrated as an embodiment of the invention, is ininany of its features identical with the service switch illustrated in the application of John A. Jessen, Serial No. 200,591, filed November 6, 1917, to which reference may be had for a detailed description of the parts tol which reference hereinafter will be but do, as will be explained, they quickly move 0f course it will be understood that theV brieiiy made.
terms which are herein used, such as front, rearf7 topf7 bottom, sides etc., are all intended in their relative senses and are not used in any limiting sense.
The mechanism is located within a case pointed vout in cated as a whole at 10, and the removable Y cover is indicated at 11, being provided with thelaterally sliding door 12 (see Figure 3). Secured to the bottom of the box there is a removable plate 13 to which are attached the two blocks 14, 14, of slate, fiber or other insulating material. vUpon these blocks are secured the stationary contacts 15, 15, with which electrical conductors may be connected in any suitable way` after being passed through apertures in the box which is preferably provided with the ordinary knockout plugs commonly in use. I have illustrated the stationary contacts as being of the spring-'clip variety to engage knife members between the jaws thereof. Movable between the blocks 14 there is a slide comprising a plate 16 and a bloclr 161 of insulating material, upon which are secured the movable switch knife members 17, 17. These memc prevent access to the current-carrying contacts 15, the slide is provided with the parallel side walls 19 of liber or otherinsulating material and with a cross wall 20 of the same material. The walls 19, 19, are spaced no further apart than the width of the opening which is closed by the sliding door 12. For the purpose of guiding the slide, the plate 13 is provided with upturned marginal portions 21 which are turned inwardly as at22 (see Figure 4) to form guideways for vthe down-turned side marginal portions 23 of the plate 16 which constitutes a portion of the slide. The slide is normally held in its open position to the right, as shown in Figures 1 and 3, by springs 24, 24, which have their rear ends attached to the plate 13 and their front ends attached to the plate 16 of the slide. The slide is moved to closed position against the tension of the springs, and, as soon as the springs are able so to movement of the slide will now be explained. It comprises a handle lever 25, having upon its end a knob 125. The hub of the handle is secured upon the upper end of a spindle E26r which is journaled in the box and extends through the cover thereot so that the handle may be secured upon its projectingr end as by a screw 22T and washer 12T. '.lhis spindle is connected with a crank arm 33, as illustrated in Figure 3, and they are capable ot a predetermined rotative movement one in relation to the other. Said crank arm has an axially `extended hub 27 provided with an axial socket 28 at its upper endfto 'receive the lower end Q9 o't' the spindle 26. The hub is stepped at its lower end in an aperture in the base plate 123, and it is also mounted to rotate in an aperture in a plate 30 secured to an upright 3l attached to the upturned end ot said plate 13. The spindle 26, in addition to being; journaled at its lower end in the hub 2T, is journaled in an inwardly projecting bracket 32formed by bending` the upper end of the upright 31, and said spindle is also journaled in the hole in the cover through which its upper portion projects. To the crank arm is pivoted one end ot an elongated curved link or connection etby a pivot pin 35 to constitute therewith a toggle which may be brought into two dead-center positions alternately. The other end ot the link 34 is `pivoted b v a rivet 537 to a lug 3G attached to the under side of the slide plate 1G, as shown in Figure The crank arm 33 may be rotated through an arc o't a little greater than 180.0 until it has `inst past a dead-center position as shown in Figure 5, the link 3l being' curved to permit this movement. Then the hub has been rotated to this position, it will be seen that the slide is locked by the toggle in its closed position with Jthe movable contact 17 in mechanical and electrical Contact with the stationarg1 contacts 15. By rotating` the section or hub 27 anti-clockwise until `the crank arm has been swung out of its said dead-center-position1 the springs 2d quickly move the slide to its open position, and this will occur upon release el" crank 33 during` any part oi its movement clockwise until the crank arm has actually reached a deadcenter position when the toggles are straight and hence. in the second ilead-center position, the slide is locked in its open position with the contacts separated. The hub 2T is provided with two separated stops or shoulders 38, 138, which are 'formed bv cut` ting,` away a portion o'f the upper end thereot and the spindle is provided with a lugl or pin 39 which mayv pla)v between these two stops. As shown` the stops or shoulders are separated by an angle ol' about 1200. although this angle may vary. A coiled spring Ll() encircles the spindle 26, one end thereof beingl secured in a hole L L1 in the upper end o't' the hub 27, and the other end olf the spring bearing against a lug' or projection e2 extending radially trom the spindle QG. This springl exerts its tension upon the spindle QG to rotate it clockwise so as normally to hold the stop pin 3f) iu engagement with the stop 3S on the hub 2G. Consequently, it the handle be swung 'trom the position shown in Figure t clockwise through an arc oli a little more than 1800, the pin or lug 39 engaging the stop or shoulder 38 will rotate the hub 27 and the crank arm 33 through an arc ot 180O until the crank arm is moved from the position shown in Figure 1 to the position shown in Figure 2. lt, during` this movement and betere the crank arm reaches its dead-centra position, the handle be released, the springs l will return the slide to its open position, and, oitl course, rotate the operating spindle in a direction lanti-clockwise throufgfh the spring; d0. This is illustrated in Figure (i, in which the spindle is released when the parts have. reached the positions indicated in itull lines, the positions indicated by the broken lines showinghow the parts are resuming; their normal positions with the slide open and the movable contacts disengaged from the rstationary contacts. 1When the parts, however, have reached the closed position with the toggle at a dead-centen the operating handle ina)T now be swungl anti-clockwise through a predetermined arc without ailecting the slide. That is, the spindle 96 may be rotated anti-clockwise until the pin or lug 39. atter leaving the shoulder 38, engages the shoulder 138 (this being permitted b v spring' 40 which is not so strong as to prevent it), and continuing its movement rotates the crank arm anti-clockwise out oit its dead-center position, whereupon the slide will immediately snap open under the tension ot the springs 24, and the cran r arm and its hub will have a 'tree rotative movement anticlockwise relatively to the spindle 26 until the stop shoulder 38 engages the lug or pro jection S9. Thus it will be seen that, while power is transmitted directl \v trom the handle to the slide (through the spindle QG, the iup; 39, the stop .shoulder litt the crank arm 33 and the link dit) to move said slide to open position; vetr when the handle :25 is moved anti-clockwise or in the opposite direction, it swings through an are (determined bv the distance between the shoulders 3S. 13S and the width oil the pin C59) without all'ectinig the slide7 and also that. when the stop or lug` engages the stop 138 and moves the hub il? anti-clockwisrzthrough a short are until the crank arm has been moved out ot .its dead-center position` the lower section is thereafter rotated :inticlockwise independentl'i,r ot the spindle as the slide snaps open7 'thus makiny a uiirl-z break. The opening movement of the slide, due to the action of the springs, 24:, is assisted and accelerated by the action of the spring 40 which has had power stored therein by the previous anti-clockwise movement of the spindle 26. The cover may have thereon the 'words Off and On, or words of similar import, located at the points at which the handle comes to la state of rest, when the slide is in its respective open and closed positions. When' the slide is closed or open, the spring a() of course holds the handle in its on or 0E positions.
In connection with the upper part of a section of the spindle, I preferably provide interlocking mechanism to prevent the handle from being operated when the door is opened and to prevent the door from being opened when the handle is in its closed position, that is, when the switchrhas been moved to closed position. For this purpose, the upper part of the handle is provided with the member 43 for cooperation with the rib 44 on the door.' I have not shown these parts in detail as they are illustrated and described in the application hereinbefore referred to.
It may sufiice to state that the member t3 is a disk having a flat face 43 on its periphery which engages the flange or rib la `extending inwardly along the lower edge of the door when the latter is open to hold the rock shaft against rotative movement and thus to lock the slide or carrier in open position. When the door is in closed position and the rock shaft is rotated to move the carrier to closed position, an arcuate portion of the member 43 moves into the path of the Hange or rib, as shown in dotted lines in Figure 3, and thus locks the door in closed position.
There are numerous advantages incident to the construction which I have illustrated and thus described which will be apparent to those skilled in the art. Among the chief of these advantages are that it is impossible for an operator to leave the switch only partly closed, because this cannot occur until the crank arm has been moved to a deadcenter position wherei` it locks the slide in its closed position; and that, as soon as the handle has been moved anti-clockwise suficiently to move the crank arm out of its dead-center position, the slide snaps open independently of the further rotative movement of the operating handle.
It is evident that various changes may be made in the particular structure which I have herein described without departing from the spirit and scope of the invention as defined and claimed,
Having, thus explained the nature of my said invention and described a way of making and using the same, although without attempting to set forth all of the forms in which it may be made or all of the modes of its use, what I claim is:
l. A service switch comprising a slide carrying movable contacts, a toggle including a straight link and a curved link arranged to move said slide in opposite directions to closed and open positions respectively,and, when in dead-center positions, to lock said slide in said open and closed positions, spring mechanism for automatically moving said slide to open position, an oscillatory member, and lost-motion means connecting said toggle and said member whereby said slide is operated in one direction to closedr and locked position by said member and said toggle, and said slide may be operated in the other direction to open and locked position by said spring mechanism independently of said member.
2. A service switch comprising a slide carrying movable contacts, a toggle including a straight link and a curved link are ranged to move said slide in opposite directions to closed and open positions respectively,v and when in dead center positions to lock said slide in said open and closed positions, spring mechanism for automatically moving said slide to open position, an oscillatory member, lost motion means connecting said toggle and said member, whereby said slide is operated in one direction to closed and locked position by said member and said toggle, and said slide may be operated in the other direction to open andlocked position by said spring mechanism independently of said member, and a spring normally holding said member at one limit of motion relative to said lost motion means.
3. A service switch comprising stationary contacts, a slide arranged between said stationary contacts and having laterally projecting movable contacts, spring mechanism for moving said slide to open position, a crank arm, a curved link connecting said crank arm to said slide and having a jonrnaled hub, said link and arm constituting a toggle adapted in its dead-center positions to lock said slide in its closed and open positions respectively, and means for operating said crank comprising a spindle journaled in said hub, a handle thereon, coacting stops between `the spindle and the hub of the crank arm to permit a limited play between them. anda spring coiled about said spindle and having one end connected to said spindle and the other end connected to said hub.
4;. A service switch comprising a closed box or case, guides stationarily supported within the case, a slide adapted to reciprocate on said guides, laterally-projecting movable contacts on said slide, stationary contacts between which the slide is located and with and from which the movable contacts may be connected and disconnected, spring mechanism 'for moving said slide to open position, a hub journaled .in stationaryv bearings in the box and having an arm, a curved link connecting the arm with said slide, said link and arm constituting a toggle which in dead-center positions locks the slide in its open and closed positions respectively, a rock-shaft projecting through the front wall oi the box, said shaft and hub having a lug` and spaced stops, a coiled spring having' one end secured to the shaft and the other end secured to the hub, and a handle located on said shalt outside the liront Wall or the case, substantially as and for the purpose set forth.
A service switch comprising` a closed box or case, guides stationarilT supported within the case, a slide adapted to reciprocate on said guides, laterally-projecting .movable contacts on said slide, a iusc on the front face of said slide in electrical engagement with said contacts, a movable door ilor said case positioned in front of said fuse, stationary contacts between which the slide is located and with and from which the movable contacts may be connected and disconnected, spring mechanism for moving;` said slide to open position, a hub jour naled in stationary bearings in the box and having` an arm, a curved link connecting the arm with said slide, said link and arm constituting a toggle which in dead center positions locks the slide in its open and closed positions respectively, a rock shaft projectin b through the front Wall of the box, said shaft and hub having a lug and spaced stops. a coiled spring having,` one end secured to the shaft and the other end secured to the hub, and cooperating members on said hub and door for preventing the opening of said door except when said hub is in position to insure the disconnection of said movable and fixed contacts.
ln testimony whereof I have aiiixed my signature.
GRANVILLE E. PALMER.
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