US2401801A - Switch operating mechanism - Google Patents

Switch operating mechanism Download PDF

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US2401801A
US2401801A US369372A US36937240A US2401801A US 2401801 A US2401801 A US 2401801A US 369372 A US369372 A US 369372A US 36937240 A US36937240 A US 36937240A US 2401801 A US2401801 A US 2401801A
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switch
rotatable element
switch lever
motor
closed position
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US369372A
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Robert S Seese
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    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01HELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H71/00Details of the protective switches or relays covered by groups H01H73/00 - H01H83/00
    • H01H71/10Operating or release mechanisms
    • H01H71/66Power reset mechanisms
    • H01H71/70Power reset mechanisms actuated by electric motor

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  • My invention relates to switch operating mechanisms, and more especially to power-operated switch opera-ting mechanisms, wherein the operation o'f aswitcli or circuit breaker is controlled by power as regards the closing of the switch, and by overload tripping means as regards the openingof the switch.
  • the object 1" my invention is to provide a simple, inexpensive and reliable device for opening-a switch protecting a circuit, inca-se-o-f overload or abnormal conditions in the circuit, and for closing the switch by power means upon the application to the device of an impulse produced either manually, or automatically by a suitable timing device, which timing device may be driven either independently, or by the same or other driving means which drives the switch operating mechanism, the switch closing operation being madepromptly and reliably upon the application of such impulse.
  • the motor may be used for other purposes, such as the operation of a timing device, during the interval between the opening of the switch and the time when it is desired to eifect a closure.
  • the continuous operation of the motor during switching operations makes possible faulty operation, or rather successive operations known as pumping if the switch is closed into a faulty circuit, and it is the primary object of this specification to describe a mechanism not subject to such faulty or repeated operation when an impulse, either from a timing device or from a manual source has been transmitted to the mechanism.
  • Fig. 1 represents a side elevation, semi-diagrammatic, of a switch-closing mechanism embodying the features of my invention, the switch being shown in closed position;
  • Fig. 2 a similar view, with certain parts omitted, the switch being in open position;
  • FIG. 3 a similar view, differing from the preceding figures principally in the mechanical linkage between the switch-closing instrumentality and the switch, the latter being shown in closed position; 7
  • FIG. 4 a view similar to Fig. 3, with switch in open position;
  • Fig. 5 an end view of the switch lever
  • FIG. 6 an end View, in third angle projection, of the switch-closing instrumentality shown in Figs. 1 and 2.
  • a switch I is connected between supply circuit 2 and load circuit 3, the switch contacts being controlled by the movement of a switch rod 4 and attached switch lever 5.
  • One end of a bar 6 is adapted to engage a pin or roller '1' on the end of lever 5, the other end of bar 6 terminating in an eccentric strap 8 enclosing eccentric 9 which is mounted on shaft Ill.
  • bar 3 With the switch closed as in Fig. l, and tending toward an open position thru biasing means represented by spring ll, bar 3 is therefore interposed between switch lever 5 and concentric 9, and holds the switch in closed position.
  • the eccentric 9 may be maintained in this position by friction with its strap 8, or a suitable retain: ing means, not shown herein, may be employed.
  • an impulse either manual, or automatic from an associated timing device depresses the leading end of pawl 19 just prior to its arrival at the lug 20, which is attached to eccentric 9, so that pawl l9 engages lug 20, thereby causing disc [8 to carry eccentric 9 around with it, both disc I8 and eccentric 9 being mounted independently-onshaft 40.
  • the first portion of the rotation of eccentric 9 withdraws the notched end of bar 8 sufiiciently to permit its re-engagement with pin 1; the remainder of its rotation, completing one revolution, forces switch lever back into its original position, closing switch I.
  • a motor switch having a snap action, which would remain closed until eccentric 9 had fully completed its revolution could obviously be used to replace the type of switch indicated at I5, and it is equally obvious that if any associated mechanism, such as a resetting device for the timing mechanism required motor power after the closing of switch I, a suitable switch could be provided at I5 which would be closed by the opening action of switch I, and opened by some other instrumentality at a later time.
  • impulse means the application of pressure to pawl I9, whether by manual, automatic or remote control means, suflicient to cause engagement of pawl IS with lug 20. According to the structures shown, such impulse must be efiective in so depressing pawl I! when the pawl is between fixed stop 22 and lug 20, in order that the pawl may be out of reach of either at the time it is depressed, and so effect proper engagement of the pawl with lug 20.
  • switch operating mechanism the combination of a switch, a switch lever connected thereto, a rotatable element, switch lever actuating means releasably connecting the switch lever and the rotatable element, actuating means for the rotatable element including a motor, said actuating means being normally free of each other, a clutch member carried by the actuating means and engageable with the rotatable element, and means located in a, fixed position in the path of movement of the clutch member for effecting disengagement of the clutch member from the rotatable element when the switch lever has been moved to circuit closed position, whereby continued operation of the motor will be ineffective to produce repeat operations of the switch lever.
  • switch operating mechanism the combination of a switch, a switch lever connected thereto, a rotatable element, switch lever actuating means releasably connecting the switch lever and the rotatable element, actuating means for the rotatable element including a motor, said actuating means being normally free of each other, a clutch member carried by the actuating means and engageable with the rotatable element, overload responsive means for releasing the switch lever, and means located in a fixed position in the path of movement of the clutch member for effecting disengagement of the clutch member from the rotatable element when the switch lever has been moved to circuit closed position, whereby continued operation of the motor will be ineffective to produce repeat operations of the switch lever.
  • a switch lever a rotatable element
  • thrust means comprising a bar l'eleasably connected at one end to said switch lever and connected at the other end to said rotatable element, overload responsive means for disconnecting said thrust means from said switch lever, actuating means effective to produce a predetermined rotative movement of the rotatable element in a portion of which movement the thrust means is engaged with said switch lever and in another portion said switch lever is advanced to circuit closed position
  • a motor and means for connecting the motor with the rotatable element including a clutch member engageable with the rotatable element, and means located in a fixed position with relation to the path of movement of the clutch member to effect disengagement of the same from the rotatable element when the switch lever has been moved to circuit closed position.
  • a switch lever a rotatable element
  • thrust means comprising a bar releasably connected at one end to said switch lever and connected at the other end to said rotatable element, overload responsive means for disconnecting said thrust means from said switch lever, actuating means effective to produce a predetermined rotative movement of the rotatable element in a portion of which movement the thrust means is engaged with said switch lever and in another portion said switch lever is advanced to circuit closed position
  • a motor and means for connecting the motor with the rotatable element including a pivoted pawl engageable with the rotatable element, and a fixed stop located in the path of movement of the pawl and arranged to effect disengagement of the same from the rotatable element when the switch lever has been moved to circuit closed position.
  • a switch lever a rotatable element
  • thrust means comprising a bar releasably con nected at one end to said switch lever and connected at the other end to said rotatable element, overload responsive means for disconnecting said thrust means from said switch lever, actuating means effective to produce a predetermined rotative movement of the rotatable element in a portion of which movement the thrust means is engaged with said switch lever and in another portion said switch lever is advanced to circuit closed position
  • a motor and means for connecting the motor with the rotatable element including a clutch, and means for operating the clutch to disconnect the motor from the rotatable element when the switch lever has been moved to circuit closed position.

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Description

Junell, @946. R. s. sEEsE SWITCH QPERATING MECHANISM Filed Dec. 10, 1940 INVENTOR Patented June 11, 1946 UNITE-D STAT ES PATENT OF Fl CE SWITCH OPERATING MECHANISM Robert S. Seese, Detroit, Mich.
Application December 10, 1940, Serial No. 369,372
My invention relates to switch operating mechanisms, and more especially to power-operated switch opera-ting mechanisms, wherein the operation o'f aswitcli or circuit breaker is controlled by power as regards the closing of the switch, and by overload tripping means as regards the openingof the switch.
The object 1" my invention is to provide a simple, inexpensive and reliable device for opening-a switch protecting a circuit, inca-se-o-f overload or abnormal conditions in the circuit, and for closing the switch by power means upon the application to the device of an impulse produced either manually, or automatically by a suitable timing device, which timing device may be driven either independently, or by the same or other driving means which drives the switch operating mechanism, the switch closing operation being madepromptly and reliably upon the application of such impulse.
Other objects of my invention will appear in the further and more detailed description whic follows.
It is common practice to provide a switch or circuit breaker with a power-operated mechanism having a motor or solenoid which, when energized, operates to close the switch. It is also common practice to provide a switch with apower-operated mechanism in which the driving motor is energized immediately when the switch opens, and in which suitable devices interposed between the motor and the switch are held ineffective until it is desired to close the switch, one instance of such practice being described in my U. S. Patent 1,954,849. The advantage of starting the motor immediately upon opening of the switch is, that the motor will have attained substantially full speed by the time the closing impulse is received by the closing mechanism, and hence, maximum torque is therefore immediately available to close the switch. An additional advantage is, that the motor may be used for other purposes, such as the operation of a timing device, during the interval between the opening of the switch and the time when it is desired to eifect a closure. 'The continuous operation of the motor during switching operations, however, makes possible faulty operation, or rather successive operations known as pumping if the switch is closed into a faulty circuit, and it is the primary object of this specification to describe a mechanism not subject to such faulty or repeated operation when an impulse, either from a timing device or from a manual source has been transmitted to the mechanism.
10 Claims. (Cl. 200-92) Reference is had to the accompanying drawing in which Fig. 1 represents a side elevation, semi-diagrammatic, of a switch-closing mechanism embodying the features of my invention, the switch being shown in closed position;
Fig. 2, a similar view, with certain parts omitted, the switch being in open position;
Fig. 3, a similar view, differing from the preceding figures principally in the mechanical linkage between the switch-closing instrumentality and the switch, the latter being shown in closed position; 7
'Fig. 4, a view similar to Fig. 3, with switch in open position;
Fig. 5, an end view of the switch lever;
Fig. 6, an end View, in third angle projection, of the switch-closing instrumentality shown in Figs. 1 and 2.
Referring to Fig. 1, a switch I is connected between supply circuit 2 and load circuit 3, the switch contacts being controlled by the movement of a switch rod 4 and attached switch lever 5. One end of a bar 6 is adapted to engage a pin or roller '1' on the end of lever 5, the other end of bar 6 terminating in an eccentric strap 8 enclosing eccentric 9 which is mounted on shaft Ill. With the switch closed as in Fig. l, and tending toward an open position thru biasing means represented by spring ll, bar 3 is therefore interposed between switch lever 5 and concentric 9, and holds the switch in closed position. The eccentric 9 may be maintained in this position by friction with its strap 8, or a suitable retain: ing means, not shown herein, may be employed.
Upon the occurrence of an overload of-predetermined intensity in load circuit 3, current from current transformer 12 energizes trip coil l3, whose plunger I4 rises and strikes 'bar- 6, forcing its notched end out of engagement with pin T,'al1owing switch I to open. The opening action of the switch lever 5 closes motor switch I 5, energizing motor l6 thru a suitable motor power source l1, thus rotating disc 18 thru suitable gearing, here represented by a worm on the motor shaft, and worm wheel teeth on the periphery of disc [8. v
To close the switch, an impulse, either manual, or automatic from an associated timing device depresses the leading end of pawl 19 just prior to its arrival at the lug 20, which is attached to eccentric 9, so that pawl l9 engages lug 20, thereby causing disc [8 to carry eccentric 9 around with it, both disc I8 and eccentric 9 being mounted independently-onshaft 40. The first portion of the rotation of eccentric 9 withdraws the notched end of bar 8 sufiiciently to permit its re-engagement with pin 1; the remainder of its rotation, completing one revolution, forces switch lever back into its original position, closing switch I. At the completion of the revolution just described, end 2I of pawl I9 engages fixed stop 22, bringing pawl I9 with a wiping action out of engagement with lug 20, thereby stopping the eccentric 9. This method of causing one complete revolution of eccentric 9 by a single impulse directed at pawl I9 is analagous to the motion ordinarily found in punch press mechanisms, and no invention is claimed for this action per so. It will be noted also that the closing of switch I also causes simultaneous opening of motor switch I5, the inertia of moving parts being sufficient to complete the revolution of eccentric 9. A motor switch having a snap action, which would remain closed until eccentric 9 had fully completed its revolution could obviously be used to replace the type of switch indicated at I5, and it is equally obvious that if any associated mechanism, such as a resetting device for the timing mechanism required motor power after the closing of switch I, a suitable switch could be provided at I5 which would be closed by the opening action of switch I, and opened by some other instrumentality at a later time.
In the modification of this switch operating mechanism shown in Figs. 3 and 4, the action is similar, except that a cam 23 is used instead of eccentric 9, and a three-part joined bar assembly 2425-26 is used instead of bar 6. In this device, bar 24 turns about a'fixed shaft 21, its free end being attached to toggle members 25-25, the other end of the toggle assembly being attached to a pin 28 on switch lever 5. In Fig. 3, which represents the mechanism in a closed position, the assembly 24-45-26 is in compression, bar 24 resting on cam 23, switch I being held closed. The action of trip coil plunger I4 breaks toggle 2528, allowing switch I to open. Upon depressing pawl I9, lug 20 is engaged, causing cam 23 to make one complete revolution, in the same manner as previously described for eccentric 9, the first portion of such revolution permitting lever 24 to fall, straightening out toggle members 2526, the latter portion raising lever 24 back into the position indicated in Fig. 3, the corresponding pressure serving to force switch lever I back into its closed position by pressure thru the straightened toggle members, thus closing switch I. In this case, as in the structure shown in Figs. 1 and 2, the pawl I9 is wiped out of engagement with lug 20 upon the completion of one revolution, preventing further rotation of cam 23 until another impulse has been received by pawl I9.
The word impulse as used herein means the application of pressure to pawl I9, whether by manual, automatic or remote control means, suflicient to cause engagement of pawl IS with lug 20. According to the structures shown, such impulse must be efiective in so depressing pawl I! when the pawl is between fixed stop 22 and lug 20, in order that the pawl may be out of reach of either at the time it is depressed, and so effect proper engagement of the pawl with lug 20.
I do not desire to restrict this invention to the particular construction herein disclosed, as it is obvious that other forms may be employed withoutdeparting from the spirit of the invention.
What I claim is:
1. In switch operating mechanism, the combination of movable switch contacts, a switch lever connected thereto, a thrust member arranged to move said switch lever to and to maintain it in circuit closed position, means for rendering the thrust member inoperative to maintain the switch lever in circuit closed position, means for actuating the thrust member comprising a rotatable element directly engageable with the thrust member, said rotatable element in its initial movement being efiective to restore e1- fectiveness of said thrust member and then move the thrust member to close said contacts and maintain the switch lever in circuit closed position, a motor, means for connecting the motor with the rotatable element for rotating said element including a clutch member engageable with the rotatable element, and means located in the path of movement of the clutch member for moving the same out of engagement with the rotatable element when the latter has made substantially a single revolution, whereby the switch lever will be maintained in circuit closed position and continued operation of the motor will not produce repeat operations of the switch lever.
2. In switch operating mechanism, the combination of movable switch contacts, a switch lever connected thereto, a thrust member arranged to move said switch lever to and to maintain it in circuit closed position, overload responsive means for rendering the thrust member inoperative to maintain the switch lever in circuit closed position, means for actuating the thrust member comprising a rotatable element directly engageable with the thrust member, said rotatable element in its initial movement being effective to restore effectiveness of said thrust member and then move the thrust member to close said contacts and maintain the switch lever in circuit closed position, a motor, means for connecting the motor with the rotatable element for rotating said element including a clutch member engageable with the rotatable element, and means located in the path of movement of the clutch member for moving the same out of engagement with the rotatable element when the latter has made substantially a single revolution, whereby the switch lever will be maintained in circuit closed position and continued operation of the motor 'will not produce repeat operations of the switch lever.
3. In switch operating mechanism, the combination of a switch, a switch lever connected thereto, a thrust member arranged to move said switch lever to and to maintain it in circuit closed position, overload responsive means for rendering the thrust member inoperative to maintain the switch lever in circuit closed position, means for actuating the thrust member comprising a rotatable element directly engageable with the thrust member, said rotatable element in its initial movement being eifective to restore eiiectiveness of said thrust member and then move the thrust member to close said switch and maintain the switch lever in circuit closed position, means for rotating the rotatable element including a motor,
gearing connected with the motor, a clutch membcr carried by the gearing and engageable with the rotatable element, whereby said rotatable element is actuated by the motor, and a fixed stop located in the path of movement of the clutch member and arranged to disengage the clutch member from the rotatable element when the latter has made substantially a single revolution. whereby the switch lever will be maintained in circuit closed position and repeat operations of the switch lever prevented should the motor continue running.
4. In switch operating mechanism, the combination of a switch, a switch lever connected thereto, a rotatable element, thrust means re leasably connecting said switch lever to said element, overload responsive means for releasing the switch lever, a motor, means for connecting the motor with the rotatable element including a clutch member engageable with the rotatable element, and means located in the path of movement of the clutch member and arranged to effect disengagement of the same from the rotatable element when said element has moved the switch lever to circuit closed position, whereby continued operation of the motor will be ineffective to produce repeat operations of the switch lever.
5. In switch operating mechanism, the combination of a switch, a switch lever connected thereto, a rotatable element, switch lever actuating means releasably connecting the switch lever and the rotatable element, actuating means for the rotatable element including a motor, said actuating means being normally free of each other, a clutch member carried by the actuating means and engageable with the rotatable element, and means located in a, fixed position in the path of movement of the clutch member for effecting disengagement of the clutch member from the rotatable element when the switch lever has been moved to circuit closed position, whereby continued operation of the motor will be ineffective to produce repeat operations of the switch lever.
6. In switch operating mechanism, the combination of a switch, a switch lever connected thereto, a rotatable element, switch lever actuating means releasably connecting the switch lever and the rotatable element, actuating means for the rotatable element including a motor, said actuating means being normally free of each other, a clutch member carried by the actuating means and engageable with the rotatable element, overload responsive means for releasing the switch lever, and means located in a fixed position in the path of movement of the clutch member for effecting disengagement of the clutch member from the rotatable element when the switch lever has been moved to circuit closed position, whereby continued operation of the motor will be ineffective to produce repeat operations of the switch lever.
'7. In switch operating mechanism, the combination of movable switch contacts, a switch lever connected thereto, a thrust member adapted to move said switch lever to and to maintain it in circuit closed position, means for rendering said thrust member inoperative to maintain said switch lever in circuit closed position, means for actuating said thrust member comprising a rotatable element, said rotatable element in its initial movement being efiective to restore the effectiveness of said thrust member in closing said contacts and maintaining the switch lever in circuit closed position, a, motor, and means for connecting the motor with the rotatable element including a clutch member engageable with the rotatable element, and means located in a fixed position in the path of movement of the clutch member and effective to disengage the same from the rotatable element when the switch lever has been moved to circuit closed position, whereby continued operation of the motor will be ineffective to produce repeat operations of the switch lever.
8. In switch operating mechanism, the combination of a switch lever, a rotatable element, thrust means comprising a bar l'eleasably connected at one end to said switch lever and connected at the other end to said rotatable element, overload responsive means for disconnecting said thrust means from said switch lever, actuating means effective to produce a predetermined rotative movement of the rotatable element in a portion of which movement the thrust means is engaged with said switch lever and in another portion said switch lever is advanced to circuit closed position, a motor, and means for connecting the motor with the rotatable element including a clutch member engageable with the rotatable element, and means located in a fixed position with relation to the path of movement of the clutch member to effect disengagement of the same from the rotatable element when the switch lever has been moved to circuit closed position.
9. In switch operating mechanism, the combination of a switch lever, a rotatable element, thrust means comprising a bar releasably connected at one end to said switch lever and connected at the other end to said rotatable element, overload responsive means for disconnecting said thrust means from said switch lever, actuating means effective to produce a predetermined rotative movement of the rotatable element in a portion of which movement the thrust means is engaged with said switch lever and in another portion said switch lever is advanced to circuit closed position, a motor, and means for connecting the motor with the rotatable element including a pivoted pawl engageable with the rotatable element, and a fixed stop located in the path of movement of the pawl and arranged to effect disengagement of the same from the rotatable element when the switch lever has been moved to circuit closed position.
10. In switch operating mechanism, the combination of a switch lever, a rotatable element, thrust means comprising a bar releasably con nected at one end to said switch lever and connected at the other end to said rotatable element, overload responsive means for disconnecting said thrust means from said switch lever, actuating means effective to produce a predetermined rotative movement of the rotatable element in a portion of which movement the thrust means is engaged with said switch lever and in another portion said switch lever is advanced to circuit closed position, a motor, and means for connecting the motor with the rotatable element including a clutch, and means for operating the clutch to disconnect the motor from the rotatable element when the switch lever has been moved to circuit closed position.
ROBERT S. SEESE.
US369372A 1940-12-10 1940-12-10 Switch operating mechanism Expired - Lifetime US2401801A (en)

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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2993964A (en) * 1958-02-18 1961-07-25 Uhde Gmbh Friedrich Spring switch currents of high strength
US3006475A (en) * 1958-09-03 1961-10-31 Helen W Aker Automatic solids discharge valve for classifiers
US3475981A (en) * 1967-11-20 1969-11-04 Powell Electric Mfg Co Motor operator for load break switch
FR2493592A1 (en) * 1980-11-05 1982-05-07 Licentia Gmbh SWITCH COMPRISING REMOTE CONTROL MEANS

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2993964A (en) * 1958-02-18 1961-07-25 Uhde Gmbh Friedrich Spring switch currents of high strength
US3006475A (en) * 1958-09-03 1961-10-31 Helen W Aker Automatic solids discharge valve for classifiers
US3475981A (en) * 1967-11-20 1969-11-04 Powell Electric Mfg Co Motor operator for load break switch
FR2493592A1 (en) * 1980-11-05 1982-05-07 Licentia Gmbh SWITCH COMPRISING REMOTE CONTROL MEANS

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