US1678878A

US1678878A - Switch mechanism

Info

Publication number: US1678878A
Application number: US583607A
Authority: US
Inventors: Maurits J Sandin
Original assignee: Westinghouse Electric and Manufacturing Co
Current assignee: CBS Corp
Priority date: 1922-08-22
Filing date: 1922-08-22
Publication date: 1928-07-31
Anticipated expiration: 1945-07-31

Description

' M. J. SANDIN SWITCH MECHANISM Filed Aug. 22 1922 2 Sheets-Sheet 1 INVENTOR I -/\aur'ifs J. Sandin.

ATTORNEY July 31, 1928.

M. J. 'SANDIN swI'rcn uncnmsu Filed Aug. 22. 1922 2 Sheets-Sheet. 2

INVENTOR Nauriis J I Sandin- WITNESSES:

G/ATTORNEY Patented July 31, 1928.

UNITED STATES PATENT OFFICE.

MAURITS J. SANDIN, OF WILKINSBURG, PENNSYLVANIA, ASSIGNOR TO WESTING- HOUSE ELECTRIO 8n MANUFACTURING COMPANY, A CORPORATION OF PENNSYL- VANIA.

SWITCH MECHANISM.

Application filed August 22, 1922. Serial No. 583,607.

My invention relates to switch mechanisms and particularly to those provided with means for automatically operating them under predetermined conditions.

One object of my invention is the provision, in a rotatable snap switch, of means for either manually or automatically effecting the operation thereof.

Another object of my invention is the of means, controlled by circuit conditions, for effecting an automatic operation of a rotatable snap switch and for automatically effecting a resetting of the automatic mechanism after each actuation 1 thereof.

Still another object is to simplify the construction of snap switches generally and to provide an improved form of operating mechanism therefor.

A further object of my invention is the provision, in a rotatable snap switch, of means whereby a single tension device may be employed to effect a snap movement thereof upon either manual or automatic operation. I I

It has been heretofore proposed to employ fusible members that are controlled by current in the circuit for permitting the switch to. open upon the occurrence of an overload, but none of the prior art of which provision I am aware has proposed to employ such a device in connection with a fully rotatable switch wherein a single tension device is employed. l

As shown in the accompanying drawings,

Figure 1 is a view, partially in side elevation and partially in section, of a switch embodying my invention,

Fig. 2 is a view thereof partially in plan and partially in section, I

Fig. 3 is a bottom plan view thereof, I

Fig. 4 is a sectional plan view of certain of the switch parts shown in the positions occupied thereby when the circuit through the switch is completed,

Fig. 5 is a similar view showing the position occupied by the said parts when the circuit through the switch is broken,

Fig. 6 is a sectional view of the thermal device whichI employ, and

Fig. 7 is a detail view of one of the locking members.

I provide av base 7 to the outer side of which are secured stationary contact members 8 and 9 that carry

terminals

10 and 11, respectively.

A turn button 12 is secured to one end of a shaft 13 that extends through the base. A ratchet wheel 15 is secured to the other end of the shaft 13. A bearing block 16 for the shaft 13 is set into a recess in the outer sideof the base 7 to relieve the base of wear through the turning of the shaft.

A gear wheel 18 lies against the base 7 and is loosely supported by the shaft 13. :A camming disc 20 (Figs. 4 and 5) is rigidly secured to the shaft 13 and abuts against the outer side of the gear Wheel 18.

A" blade carrier 22 is loosely supported upon the shaft 13, for supportinga blade or bridging member 23, being insulated therefrom-by washers 25., A spring 26 engagesthe carrier 22 and a collar 27 that is secured to the shaft 13.

The blade carrier, at its inner side, has a lock plate 28 secured thereto by rivets 29 (Fig. 7). The plate 28 is provided with a slot 30 in which slides an outwardly extending lug 31 of a camming ring 32 that surrounds the cam disc 20. The ring 32 is also provided with a radially extending portion 34 that serves as a stop member, as will be hereinafter described.

The spring 26 is normally under tensionand the shaft 13 is held against counterclockwise movement by means of the ratchet wheel 15 and the spring-pressed pawl 15a (Fig. 3). f k

The blade carrier 22 is biased, through the tension of the spring 26, in a clockwise direction. Movement thereof, however, is prevented by reason of the stop member 34 abutting against one of the stops 36 37, 38' and 39 that project outwardly from the gear wheel 18. The slot 30 in the plate 28 holds the ring 32 against rotative movement relatively to the blade carrier 22.

The gear wheel 18 is prevented from turn- -1ng, by a gear wheel 41 that is secured to a shaft 42 by fusible material, or solder, 43 (Fig. 6). cylindrical member 44 and thereby held The shaft 42 is cemented in a I against turning. It will thus be seen that,

so long as the solder 43 holds, the blade carrier 22, and the blade 23 thatis carried thereby, cannot move, unless the camming ring 32 is so moved as to carry the stop member '34 out of engagement with the

stop members

36, 37, 38, 39, carried by the gear wheel 18.

In order to advance the switch to open position, the button 12 is turned in a clockwise direction, thus increasing the tension of the spring and rotating the camming plate 20, to move the cam ring 32' to the right (Fig. 4). This movement withdraws the lug 34 from engagement with the stop member 37 and permits the blade'carrier to be advanced by the spring 26. As the carrier advances, it carries with it the camming ring 32, by reason of the engagement of the lug 31 thereof with the walls of the slot 30 in plate 28. This movement of the cam ring rotates it about the cam plate that has just been given rotative movement through 90 are, as above explained, until it has reached substantially its former position relatively to the cam plate 20, at which time the stop 34 thereof will make engagement with the stop 38 of the gear wheel 18. The bridging member 23 then occupies its open position. Further turning of the button 12 will advance the camming ring into engagement with the

stop members

39, 36 and 37, successively.

To effect an automatic" actuation of the switch, to break the circuit, when the parts are in the posit-ion shown in Figs. 1 and 4, it is necessary to release the gear wheel 18 and permit it to rotate under the action of the spring 26.

A resistance wire or heating element 46 is imbedded in the cement contained in the cylinder 44 and is connected in series with the circuit through the switch. The resistance element 46 is an extension of the lead 47 and current flows therefrom, through the shaft 42, a terminal plate 48 (Fig. 2), shunt 49,- terminal 11, contact member 9, bridging member 23, and contact member 8 to the terminal 10.

Should the current in the circuit exceed a predetermined value, the heating element 46 will cause the solder 43 to soften, thus prmitting the gear wheel 41 to rotate on the shaft 42, and releasing the gear wheel 18. The tension normally exerted by the spring 26 may now move the carrier 22, and the gear wheel 18 in a clockwise direction.

The shaft 13 and the cam plate 20 carried thereby do not move, as .they are biased in a counter clockwise direction, against the pawl 15a, by the spring 26. Therefore, the camming ring 32, byreason of its engagement with the slot of the plate 28, is rotated around the cam disc 20 until the extension 34 thereof is in substantially radial alinement with the shaft 13. At this period, the lug 31 is at the limit of its radial path of movement, and moves into engagement with a raised stop member 50 (Fig. 5) that is secured to the base 7, thus bringing the switch parts to rest at open'position.

The solder will then become cooled and the gear wheel 41 again locks the gear wheel 18 against movement. The switch is now ready for another manual operation, by

means of the button 12, whereby the lug 31 of the cam ring 32 is withdrawn from the stop member 50 and the extension 34 withdrawn from the stop 38 of the gear wheel '18. The tension of the spring 26 is meanwhile being increased and the parts are snapped into -a position wherein the cam ring extension 34 abuts against the lug 39, as heretofore described. The switch is now closed and ready for either an automatic or a manual opening operation. A further automatic operation will carry the lug 31 into engagement with the raised stop member 51 disposed diametrically opposite.the member 50 (Figs. 1 and This automatic movement is essentially the sameas the other automatic movement above described.

The'lug 31 is never entirely out of engagement with the walls of the slot 30, and, at each of the two automatically released positions of the switch, is in engagement both with one of the

stops

50 and 51 and with the slot- 30. The blade carrier 22 can never move without imparting rotative movement to the camming ring 32 and, owing to the interengagement of the ring and the cam plate 20, all movements of the ring are combined rotative and reciprocatory motions.

From the foregoing it will be seen that I provide a switch that may be automatically moved to open position and that is automatically reset for further automatic operation. Also one wherein the manual operation of the switch may be freely effected without affecting the automatic mechanism and sufficient tension stored, when closing the switch, to insure asnap movement thereof to open position when automatically released.

Various changes in detail and general arrangement may be made witliout departing from the spirit and scope of the invention as defined by the accompanying claims.

I claim as my invention:

1. The combination with a progressively rotatable switch member. of an actuating spring therefor, manually-operable means for placing the spring under tension to cause a snap movement of the said member, means for retarding the movement of the switch member, means responsive to the current inllt the circuit whenever the circuit is closed by the switch member for controlling the retarding means, and means whereby the energy stored in the spring during manual operation of the switch member to one position causes movement of the said member to another position when the retarding means is actuated.

2. The combination with a rotatable snap switch and a tension device for actuating the same, of a normally stationary stop member for retarding the movement of the switch, a stop member manually movable out of engagement with the first named stop member 'member, a carrier for sai to permit movement of the switch, a thermally-controlled member for permitting movement of the first named stop member, under predetermined conditions and a permanent stop member for arresting the last named movement at a predetermined point.

3. The combination with a rotatable switch member and a tension member therefor, of means for storing energy in said tension member, a carrier for said member, a stop member supported on the carrier, a gear wheel provided with stop members in position to be engaged by the first named stop member at predetermined positions of the said switch member, a second gear wheel meshing with the first named gear wheel, and means'responsive to conditions in the' circuit for permitting the gear wheels to rotate.

4. The combination with a rotatable switch member and a tension member therefor, means for storing energ in said tension member, a stop member supported on the carrier, a gear wheel provided with stop members in position to be engaged by the first named stop member at predetermined positions of the said switch member, a second gear wheel meshing with the first named gear wheel, a fusible member for normally maintaining the second gear wheel against movement, and a heating element in series with the switch for softening the fusible element to permit movement of the gear wheels.

5. The combination ,with a rotatable switch member and a tension member therefor. means for storing energy in said tension member, a carrier for said member, a stop member supported on the carrier, a gear wheel provided with stop members in position to be engaged bythe first named stop member at predetermined positions of the said switch member, a second gear wheel meshing with the first named gear wheel, means responsive to conditions in the circuit for permitting the gear wheels to rotate, and means'limiting the movement of the said gear wheels after they have been released.

(3. The combination with a rotatable switch member of a tension member therefor, means for storing energy in the tension member, a shaft for the rotatable member, a cam member supported by the shaft and having a locking lug thereon, a movable member provided with stop members for engaging the said locking lug, a fusible memher for normally holding the movable member against movement, means controlled by conditions in the circuit for rendering the fusible member ineffective to hold the said movable member in fixed position, and means for liniiting the movementof the said movs )rin 'for the blade member, manually op- .erable means for placing the spring under tension to cause a snap movement of the blade member, means for retarding the movement of the blade member, means at all times responsive to the current traversing the switch for controlling the retarding means, and means whereby the energy stored in the spring during manual operation of the switch causes movement of the blade member to another position when the retardingmeans is actuated.

8. In a rotatable snap switch, a progressively rotatable blade member, contact members co-operating therewith, an actuating spring for the blade member, manually operable means for placing the spring under tension to cause a snap movement of the blade member, means for retarding the movement of the blade member, means at all times responsive to the thermal action of the current traversing the switch for controlling the retarding means, and means whereby the energy stored in the spring during manual operation of the switch causes movement of the blade member to another position when the retarding means is actuated.

9. Switch mechanism comprising a contact member, a switch member movable into engagement with the contact member, means including a progressively rotatable shaft for operating the switch, andmeans manually operable to retaining position for releasably releasing the switch in engagement with the contact member, the said means being current responsive for releasing the said switch member. v

10. The combination with a rotatable snap switch and a tension device for actuating the same, of' a normally stationary stop member for retarding the movement of the switch, a stop member manually movable out of engagement with the first named stop member to permit movement of the switch, a thermally-controlled member for permitting movement of the first named stop member under predetermined conditions and a permanent stop member for arresting movement of the switch at a predetermined point. I.

11. The combination with a rotatable snap switch and a tension device for actuating the same, of a normally stationary stop member for retarding the movement of the switch, a stop member manually movable out of engagementwith the first named stop member to permit movement of the switch, a curr nt responsive member for permitting movement of the first named stop member under predetermined conditions and a permanent stop member for arresting move ment of the switch at a predetermined point.

12. The combination with a rotatable snap switch and a tension device for actuating the same, of a pair of relatively movable stop members for successively retarding the morement of the switch, a stop device for the switch manually movable out of engagement with the said stop members to permit movement of the switch, and a current responsive device for permitting relative movement of the first said stop members to release the said stop device.

13. The combination with a snap switch and a tension device for actuating it,'of a pair of cooperating movable stop members .for releasably retarding movement of the switch, one of the said members being manually operable to releasing position with respect to the other to permit movement of the switch and the other of the said members being current responsive and movable to releasing position with respect to the other to permit movement of the switch.

.In testimony whereof, I have hereunto subscribed my name this 10th day of August 1922.

MAURITS J. SANDIN.