US2461846A - Automatic switch construction - Google Patents

Description

Feb, 15 19490 (J, gcH Z 2,461,84

AUTOMATIC SWITCH CONSTRUCTION Filed Sept. 4 1945 3 Sheets-Sheet l INVEN r012. W/zmM 0. 5 0/01 rz A77 ENC X Feb. 15 1949.,

W. SCHULTZ AUTOMATIC SWITCH CONSTRUCTION Filed Sept. 4, 1943 3 Sheets-Sheet 2 lNl 'ENTOR. Mum/24 0. 50/01 rz BY QAQLM-Qa Feb. 15, 1949, w. 0. SCHULTZ AUTOMATIC SWITCH CONSTRUCTION Filed Sept. 4, 1943 1N VEN TOR. [Val/AM 0. Jam/1 72 /7 77'0fiA/E Y.

I mm-mlmm I'un Patented Feb. 15, 1949 UNITED STATES PATENT OFFICE AUTOMATIC SWITCH CONSTRUCTION William 0. Schultz, South Milwaukee, Wis., assignor to Line Material Company, South Milwaukee, Wis., a corporation of Delaware Application September 4, 1943, Serial No. 501,227

2 Claims. (Cl. 200-146) This invention relates to an automatic switch construction.

Objects of this invention are to provide a switch construction of the repeating type which is adapted to open under load, which is spring operated and is adapted to execute a number of operations before the spring needs rewinding, and which is controlled by condition responsive means, such as overload trip means, and is provided with a time delay mechanism, the time delay mechanism causing a delay before the switch is automatically again closed so that if the fault has cleared during this interval, the switch will remain closed but if the fault has not cleared, the switch will again be automatically opened, the device being provided with lockout means to lock the switch in open position after a predetermined number of operations.

Further objects are to provide means for rewinding the spring means through the use of an insulating switch stick so that the lineman will not be exposed to any danger of injury although the device may be used on high voltage distribution systems.

Further objects are to provide a switch construction in which crank means are provided which always rotates in the same direction when the switch operates, such crank means being operatively connected to a main movable contact means, and in which quick motion auxiliary movable contact means is provided which is reciprocable into a stationary insulating tube after the main movable contact means has moved to open position to thereby cause the final arc to be drawn into the tube and extinguished.

Further objects are to provide indicating means which will indicate the condition or state of the mechanism particularly with reference to the number of operations still remaining before the switch is locked out in open position, and to provide rewinding means of the ratchet type which during the initial portion of its rewinding operation causes the switch to automatically close and thereafter to open in the event the fault persists or to remain closed in the event the fault has cleared.

An embodiment of the invention is shown in the accompanying drawings, in which:

Figure 1 is a side elevation of the automatic switch.

Figure 2 is a front view of the automatic switch with parts broken away and parts in section.

Figure 3 is an enlarged view corresponding to Figure 1 with parts broken away and parts in section.

Cir

Figure 4 is a sectional view on the line 4-4 of Figure 3.

Figure 5 is a detail sectional view on the line 55 of Figure 2.

Figure 6 is a detail sectional view on the line 6--6 of Figure 2.

Figure 7 is a detail sectional view, partly broken away, on the line 1-1 of Figure 2.

The automatic switch comprises a supporting portion I which has a pair of insulators 2 and 3 projecting therefrom. The insulator 2 carries the stationary contact 4 which is provided with a terminal portion 5. This stationary contact 4 consists of a downwardly flaring conical caplike member whose inner surface is the contact surface against which the conical main movable contact 6 is adapted to normally seat to thus provide good current carrying contact surfaces. The stationary contact also includes a movable auxiliary contact consisting of a cylindrical portion 1 terminating in a head 8 adapted to be engaged by the upper end of the rod or auxiliary movable contact 9 when the switch is closed. The auxiliary stationary contact 8 is movably carried by the main stationary contact 4 and is sp urged downwardly by means of the spring 10, its downward motion being limited by means of the screw ll threaded into the cylindrical portion 1.

The lower insulator 3 carries a bracket l2 which in turn rigidly supports an insulating tube I3 within which the plunger or auxiliary movable contact 9 is slidably mounted and into which the plunger 9 is adapted to be suddenly withdrawn after the main movable contact 5 has been withdrawn from the stationary contact 4, as will hereinafter appear, so that the final arc is established between the auxiliary stationary contact 8 and the rod 9 and is drawn into and extinguished within the insulating tube l3. This tube I3 is preferably formed of a Bakelite body portion with a fiber lining. It is well known that when the fiber lining is subjected to the heat of the are, it evolves a deionizing gas which assists in quickly extinguishing the arc.

The main movable contact 6 is integral with a half shell-like portion [4 which in turn is integral with a downwardly extending tubular portion IS. The tubular portion I5 is guided by means of the guiding portions l6 of the bracket l2 and is also guided against lateral thrust to the right of the member I4 by means of the collarlike portion I! which is integral with the bracket [2 and which rigidly carries the stationary insulating tube l3. It is to be noted that the main movable contact 6 is a sleeve-like member and is 'guidedby the insulating able guiding means may be provided.v

' 1 The plunger or rod 9 extends downwardlyinto the tube l5 a'ndis provided with a latching coltube l 3.

lar l8 .beneath which a latching member I9 is normallypositioned, the latching member being pivoted on the bracket bymeans of the pivot pin 29 and being urged in a counterclockwise direction by means of the spring 2!; The latching collar i8 is provided with a beveled upper portion and with a cylindrical lower portion 22 which seats on the intermediate transverse apertured web 23 located between the shell-like portion 14 and the tubular portion l5.

It is to be noted that the slidable member composed of the parts 6, l4 and. I5 is provided with a projecting shoulder 24 which rides on the inner cam or slanting surface 25 of the latching lever Hi. The lower end of the rod 9 is provided with a head 25 against which a compression spring 21 bears. It is to be noted that when the main movable contact 6 is moved downwardly by means hereinafter to be described, the spring 21 is compressed and after the main movable contact 6 has moved away from the stationary contact 4, the shouldered portion 24 will move the latching lever iii to the right and release the plunger 9. The plunger, under the infiuenceoi the spring 2'! will quickly descend and withdraw its upper end into the insulating tube l3 and the final arc will be extinguished within the tube.

It is preferable to have the spring 21 under initial compression when the switch is closed though it is to be understood that the spring 21 may be free from compression initially.

The means for reciprocating the movable contact consists of a crank formed of the crank pin 28 carried by the disk 29, such disk being rigidly mounted on the shaft 39. The crank pin 28 is connected to the reciprocating member 6, l4, l5 by means of the connecting link 3|. The shaft 30 is provided with a flattened portion to which work inner portion such as spokes or similar 4 structure. If desired any other suitable time delay means could be provided such as a paddle wheel for instance.' The shaft 3| also carries a small gear 36 which meshes with a larger gear 31. The sleeve 34 carries a small gear 38 which mesh- Any other suit outer end adapted to receive the terminal of an insulating witch stick. It is also provided with a spring pressed pawl 46 for engaging'the pins 43. v

The crank-or disk 29 is prevented from rotating by means of a spring pressed pawl 47, see Figure 3, which seats against the shouldered portion of a notch 48. The pawl is pivotally carried on the pivotpin 49 which in turn is carried by the bracket l2. The pawl is urged in a counterclockwise direction by means of the spring 50.

It is provided with an outwardly extending arm 52 which is adapted to be pushed upwardly by a condition responsive device, such for example as the magnetically operated over-load device show. I

This overload device comprises a solenoid indicated generally at 53 and a plunger 54 which is adapted to be moved upwardly upon the flow of excessive current through'the solenoid to thus release the latching member 41 and allow the crank to r0tate.If desired, the solenoid may be formed with insulating upper and lower portions and an insulating outer shell. It is held by means of a clamp 55 secured to a bracket 56 carried by the lower portion of an insulator 51 rigidly at-.

, may freely reciprocate past the bracket without one end of a helical spring or power storing means 1 contacting the bracket. The other end of the solenoid 55 is connected by means of a flexible leader 59 with the main movable contact.

The operation oi the apparatus is as follows: When an overload occurs, the latch 47 is moved to released position and the crank is rotated'by means of the spring 32, thus first moving the main movable contact 6 downwardly and out of engagement with the stationary contact 4. After the movable contact has moved down a predetermined distance, the latching lever I 9 is tripped and the plunger 9 is suddenly drawn downwardly into the tube l3, thus extinguishing the final are within the tube. to rotate and again closes the circuit, the parts arriving at the position shown in Figure 3. If the fault has cleared, the latching lever 41 will arrest further motion of the crank. Upon the es with a larger gear 39 mounted adjacent the gear 31. The gears 31 and 39 are loosely mounted on a supporting pin 40 which is rigidly carried by the bracket l2.

The sleeve 34 is provided with a small gear 4| which meshes with a large winding gear 42, The winding gear is also loosely mounted on the pin '49. The winding gear'is provided with a plurality tation and through the medium of the small gear I ,4lcorrespondingly prevents the drum 33from reverse rotation. Winding means in the form of a winding lever 44 is loosely mounted on the pin 49 andis providedwith an apertured or eyeleted closing stroke it is apparent that the-shouldered cylindrical portion 22 of the latching collar is rests upon the transverse web 23 and the auxiliary contact or plunger 9 is restored to its initial position and the latch lever l9 moves back to its latching position as shown in Figure 3. It is to be noted that there is a slight compression of the spring NJ as the auxiliary stationary contact 8 is moved upwardly a slight distance by the rod 9. The spring in maintains'a pressure contact between the upper end of the rod 9 and the auxiliary stationary contact.

The time delay means, such as the flywheel 35 or if desired a paddle wheel or any other time delay means, causesa certain delaybetween the opening of the automatic switch and the closing thereof. Frequently the fault on the line clears during this interval and the switch remains closed. Howevenif the fault persists, the switch executes a second cycle of operations and if the fault has not cleared during the second cycle of operations, the switch continues opening and closing until the apparatus has executed all of The crank continues with a window 63.

the operations for which it is designed. After execution of the predetermined ,number of operations, the switch is locked in open position, as will appear hereinafter.

In order to both lock the switch in its final open position and also to provide indicating means to show the number of operations still remaining to be performed, the gear 31 is provided with an arcuate groove 60, see Figures 2 and 7, and the gear 39 is provided with a pin 6| designed to travel within the slot 60. In addition to this, the gear 39 is provided with a series of numerals 1 to 5 in the form chosen for illustration and with the indicium Lock as indicated at 62 in Figure 7, and the gear 31 is provided When the device is fully wound and has not executed any operations, the window 63 is opposite the numeral 5 as shown in Figure 7. When the crank executes one rotation, the gear 36 drives the gear 31 to the position where the window is opposite the numeral 4 and thus 4 indicates the number of remaining operations that the device can perform.

During the time the crank is rotating, the drum 33, the sleeve 34 and the gear 38 are held stationary. Consequently the gear 39 is held stationary. The gear 3! travels in a clockwise direction as indicated by the arrow in Figure '7. The crank can execute five operations in the form shown and if it continues to rotate; the slot 60 will have moved so that the pin 6| engages the other end of the slot from the end it is shown in engagement with in Figure 7 and consequently arrests further rotation of the crank. This position is chosen so that the switch is locked in switch open position and the window 63 is opposite the indicium Lock."

It is necessary for the device to be rewound before it will again be placed in operation. This is accomplished by the lineman engaging his insulated switch stick in the eyelet 45 of the winding lever 44 and rocking this lever back and forth downwardly and upwardly. As he rocks the lever, the pawl 46 successively engages the pins 43 and rotates the gear 42, thus rotating the gear 4| and the drum 33 and winding the spring 32. In view of the fact that the gear 38 is rigid with the sleeve 34, such gear will rotate and will in turn cause the gear 39 to rotate. This winding continues until the gears 42 and 39, which have the same ratios with respect to their pinions 4| and 38, have made one complete revolution and the parts are in the position shown in Figures 2 and '7.

The parts are so proportioned that when the lever 44 is moved downwardly, it will move two of the pins 43 past the pawl 44. Two successive spaces between the pins 43 correspond to one complete revolution of the crank. Consequently at the first down stroke of the lever 44, the crank will immediately close the switch and if there is no fault, the switch will remain closed. On the other hand, if there is a fault, the switch will immediately open.

Assuming that there is no fault, the winding handle 44 or winding lever is rocked back and forth and the spring 32 is completely rewound, the pin 6| traveling during this time within the slot 60 and arriving at the position shown in Figure 7 and stopping further winding operations, thus protecting the spring against over winding.

It is to be noted that in the form chosen for illustration the device is designed for five operations and ten pins 43 are provided.

Other condition responsive means could be 6 employed in place of the overload solenoid if so desired, or other tripping means could be employed.

It is to be noted that the insulating tube I3 is held rigidly by the bracket l2 and is at all times spaced from the stationary contact 4. It is also to be noted that the stationary contact 4 forms a hood or shield which always shields and protects the upper end of the tube 13 from the entrance of water or snow. In addition to this, the upper inverted conical stationary contact 4 acts as a shield for the normal position of the movable main and auxiliary contacts. It is to be noted further that the spring 21 is housed within the tubular portion 15 of the movable member.

It will be seen that a repeating automatic switch construction has been provided which is designed to open under load and to immediately extinguish the resulting arc to protect the parts against damage. It will be seen further that the device is relatively simple and does not require any particular skill on the part of a lineman as all he is required to do is to rock the winding lever 44 back and forth by means of a switch stick. The device is fully automatic in its action and even if the lineman attempts to rewind the device while the fault still persists, the switch will automatically open as described hereinabove. It frequently happens that on distribution systems the faults are of relatively short duration and thus it will be seen that this device is eminently suited to fulfill the needs of such systems as it will immediately open the circuit when the fault occurs and will provide a predetermined time delay before again closing the circuit. It will be seen, however, that if the fault is permanent, the device will ultimately lock itself in switch open position.

Although this invention has been described in considerable detail, it is to be understood that such description is intended as illustrative rather than limiting, as the invention may be variously embodied and is to be interpreted as claimed.

I claim:

1. A switch construction adapted to open under load comprising a stationary insulating tube, a stationary contact, a main movable contact and an auxiliary movable contact adapted to engage and disengage said stationary contact, said auxiliary movable contact consisting of a plunger within said tube, said main movable contact consisting of a sleeve-like member guided by said tube and located exteriorly of said tube, spring means for drawing said plunger into said tube away from said stationary contact, latch means normally preventing motion of said plunger, mechanism for moving said main contact into and out of engagement with said stationary contact, and tripping means for tripping said latch means on movement of said main movable contact to open position.

2. A switch construction adapted to open under load comprising an insulating tube, a stationary contact, a main movable contact and an auxiliary movable contact adapted to engage and disengage said stationary contact, said stationary contact having yielding means coacting with said auxiliary movable contact, said auxiliary movable contact consisting of a plunger within said tube, said main movable 'contact consisting of a sleeve-like member guided by said tube and located exteriorly of said tube, spring means for drawing said plunger into said tube away from said stationary contact, latch means normally preventing motion of said plunger, mechanism 9,401,846 7 n 8 for moving said main contact into and out or Number Name Date engagement with said stationary contact, and 1,028,993 Cheney June 11, 1912 means for tripping said latch means when said 7 1,315,839 Hain Sept. 9, 1919 main movable contact is moved away from said 1,640,177 Bishop et a]. Aug. 23, 1927 stationary contact. 5 1,799,985 McCoy Apr. 7, 1931 WILLIAM O.SCHULTZ. 2,286,131 Wallace et 8.1. .-June 9, 1942 2,311,714 Thompson et a1. 4... Feb. 23, 1943 REFERENCES CITED 2.3211122 Birkenmaier et a1. June 8.1943 t cor in t 2,323,241 Richardson et a1. June 29', 1943 g; ,}':,,f a o re 10 2,824,891 Thumim July 20,1943 UNITED STATES PATENTS 2,844,113 Schultz Mar. 14, .1944

FOREIGN PATENTS Number Name Date I I 508,652 Thomson 1 Nov. 14, 1893 Number ry 1 Date 7 2,552 Hewlett Feb. 16, 1904 15 Germany July 2 1889

Images