US2894081A - Switch-actuating mechanisms - Google Patents

Description

July 7, 1959 I. TREPANIER 7 2,894,081

SWITCH-ACTUAT'ING MECHANISMS Filed May 13, 1957 3 Sheets-Sheet' 1 i 1/- INVENTORI BY I l5 6 ATTORNEY5 y 7 1959 TREPANIER 2,894,081

SWITCH-ACTUATING MECHANISMS Filed May 13, 1957 3 Sheets-Sheet 2 INVENTOR BY gym MW ATTORNEYS July 7, 1959 TREPANlER 2,894,081

SWITCH-ACTUATING MECHANISMS Filed May 13, 1957 3 Sheets-Sheet 3 Q7: 2 :i b

United States Patent SWITCH-ACTUATIN G MECHANISMS Ivan Trepanier, Waterbury, Conn., assignor to Lux Clock Manufacturing Company, Inc., Waterbury, Cnn., a corporation of Connecticut Application May 13, 1957, Serial No. 658,808

13 Claims. (Cl. 200 -38) This invention relates to electrical switch-actuating mechanism and more particularly to a mechanism to be employed with a timer for timing operations of various kinds and, while it is not limited to such an application, it is illustrated in connection with clock or timing mechanism.

In connection with timers for various operations, it is desirable that the timing mechanism shall open and close a switch at predetermined intervals. In many instances timers are so arranged that the mechanism may be set by turning an indicator hand Which'sets the timing mechanism into operation, and after a given period of time a switch will be opened to cut off electrical current to the load circuit for example. If the timing mechanism is also operated electrically, usually the openingof the switch at the end of the period for which the timer is set will also control the current delivered to the timing motor.

A switch-actuating mechanism for opening the contacts of a switch controlling an electrical circuit should desirably operate with a snap action so that the contacts will be broken quickly in order to prevent arcing between the contacts. It is, therefore, contemplated by the present invention to provide switch-actuating mechanism which, when it reaches its switch-opening position, will insure a snap action of the contacts to quickly break the current so that no arcing will result.

In elfecting this result by mechanism which is rela tively simple and economical to manufacture, a circular cam is provided having a follower adapted to drop into a recess or notch in the cam at the proper time, and thus permit the opening of the switch. The arrangement is such that the movement of the follower into the recess in the cam will be effected quickly and not gradually so as to bring about instantaneous opening of the switch contacts.

The cam is illustrated as being actuated or rotated by a clock mechanism which in this instance is electrically driven. However, the clock mechanism may, of course, be spring driven and effect the same result and, if it is desired, the cam member may be operated by hand and will effect opening and closing of the switch contacts.

One object of the present invention is to provide an efiicient switch-actuating mechanism which is economical to manufacture and which may be readily employed in connection with a timing mechanism.

A further object of the invention is the provision of a switch-actuating mechanism of the character described which may be manually set to close the switch and which is provided with a setting and indicating mechanism capable of rotation through substantially 360 degrees.

Still another object of the invention is to provide timing mechanism for actuating an electrical switch at a predetermined time, which mechanism shall be positive and instantaneous in its action and at the same time be economical to manufacture.

2,894,081 Patented July 7, 1959 Still another object of the invention is to provide a timing mechanism of the character described above wherein the indicating mechanism may be set to a position in which the switch will be closed until manually operated, the timing mechanism being locked against operation.

To these and other ends the invention consists in the novel features and combinations of parts to be hereinafter described and claimed.

In the accompanying drawings:

Fig. 1 is a front elevational view of a timer embodying my new switch-actuating mechanism;

Fig. 2 is a side elevational view of the timer shown in Fig. 1;

Fig. 3 is an enlarged sectional view on line 3-3 of Fig. 2;

Fig. 4 is a sectional view on line 44 of Fig. 3;

Fig. 5 is a sectional view on line S5 of Fig. 4;

Fig. 6 is a view similar to Fig. 5 but showing the parts in another position;

Fig. 7 is a view similar to Fig. 6 showing the parts in the position in which the switch is closed;

Fig. 8 is a sectional view on line 88 of Fig. 7;

Fig. 9 is a view similar to Fig. 3 but showing the parts in the position in which the timing mechanism is locked against movement;

Fig. 10 is a perspective view of the cam follower which actuates the switch; and

Fig. 11 is a simple form of wiring diagram showing both timer and load circuits controlled by the switch.

To illustrate an embodiment of my invention I have shown in the drawings a timing mechanism comprising a dial 1% having timing indications 11 thereon, which dial may be carried by a casing 12 secured in turn to a motor casing 13 which contains motor mechanism to drive the timing shaft to be hereinafter referred to. It is understood that the motor mechanism may be either a spring motor or an electrical motor as desired.

Referring particularly to Fig. 4, the motor output shaft is indicated at 14, to which shaft is secured a pinion 15 meshing with a gear 16 loosely mounted upon the timing or indicator shaft 17. The gear 16 is frictionally connected to the shaft 17 by means of the resilient spider 18 which has a hub portion secured to the shaft 17 and radially extending spring arms 19 which bear against the gear and frictionally connect it to the shaft.

The indicator shaft 17 extends through the casing 12 and the dial 10 and, as shown particularly in Figs. 1, 2 and 4, has rigidly secured upon its outer end an indicator 22 which may be manually grasped so as to manually turn the shaft 17 and set the indicator at any desired position relatively to the dial 11. It will be understood that when the shaft 17 is thus manually rotated the gear 16 is allowed to slip upon this shaft so that rotation of the latter is not transmitted to the pinion 15 and shaft 14.

Secured to the shaft 17 so as to rotate therewith is a cam disk 21 which, as shown in Figs. 3, 7 and 9 of the drawings, is provided with a V-shaped notch or recess 23 in its periphery, the cam being otherwise of circular shape. It will be noted that the sides of the V-shaped recess are relatively flat so as to provide moderately inclined surfaces for a purpose to be hereinafter set forth.

A substantially U-shaped spring member 24 (Fig. 5) has its bight portion embracing the shaft 17 and the arms of this U-shaped member extend outwardly toward the periphery of the cam where they are provided with laterally extending ends 25 and 26 projecting into the \'-shaped recess 23. Normally the inherent resilience of the arms of this U-shaped member maintain the free ends of the laterally turned portions 25 and 26 in close proximity, as shown in Fig. 5, although either of the arms may be moved outwardly so as to cause these ends to spread apart, as shown in Fig. 6.

This U-shaped spring member 24 is supported at its inner end by a lug 27 struck from the cam disk which holds the bight portion of the spring member against the shaft 17. The arms of the member are slidably guided in spaces 28 (Fig. 3) between the cam disk 21 and wings 29 upon a guide member 30 which also may be struck up integrally from the metal of the disk 21. While this construction effectually holds the spring member 24 in place, it permits movement of the ends of the arm thereof within the spaces 28, the inherent resilience of these arms normally holding them in the position shown in Fig. 5.

The switch mechanism, as illustrated, comprises a base 31 preferably of insulating material in which spaced contacts 32 and 33 are provided. These contacts are adapted to be closed by the bridge member 34 carried upon a leaf spring 35, the ends of which lie below lugs 36 upon the base 31. The latter is carried by spaced supporting legs 37 secured to the casing 12.

Slidably mounted between the legs 37 is a stirrup member 38 having projecting lugs 39, the lower surfaces of which are adapted to bear against the legs 37. Slidably mounted in the stirrup 38 is a plunger 40 urged upwardly by the spring 41 so that its upper end is in contact with the lower surface of a bead 42 secured to the lower surface of the spring 35.

With this construction it will be noted that the spring 35 is normally tensioned to hold the bridge plate 34 in the position shown in Fig. 3 where the switch contacts are open and the stirrup member 38 rests upon the sup ports 37. However, if the stirrup member 38 is raised into the position shown in Fig. 9, it will compress the spring 41 and thus urge the plunger 40 upwardly to move the bridge plate 34 to the position shown in Fig. 9 in which the contacts 32 and 33 are closed. It will be also noted that, as shown in Fig. 9, after the contacts have been closed an additional or overthrow movement of the stirrup member 38 is permitted, which movement may further compress the spring 41. This insures that the contacts will be fully closed and at the same time permits this overthrow movement to make allowance for tolerance in the manufacture of the parts of the mechanism.

A cam follower is provided to engage the periphery of the cam member 21 and actuate the switch bridge plate 34 to close the contacts 32 and 33, this follower being adapted to engage the stirrup member 38 for this purpose. This follower is shown in Fig. 10 and comprises a substantially U-shaped member having a base 44 and an upwardly displaced laterally extending arm 45 at one end provided at its side edges with pivot lugs 46 and 47. As shown in Figs. 3 and 9 these pivot lugs are pivotally mounted in openings 48 in the opposite walls of the casing 12 so that this member is permitted a pivotal movement about these lugs. The body portion 44 of the follower extends in front of the cam 21 and at its free end is provided with an offset arm 49 having a lower surface 50 adapted to extend over the periphery of the cam member and, when the latter is in the position shown in Fig. 3, drop into the V-shaped opening 23 of the cam. The width of the laterally extending end 49 of the follower is of a dimension to permit this member to drop between the spaced opposing ends of the arms 25 and 26 as shown in Figs. 3 and 5.

The normal or rest position of the parts thus far described is shown in Figs. 1, 3 and 5. It will be noted that the cam follower 44 is in its lowermost position in the recess 23 and the contact member 34, the stirrup member 38 and associated parts are in their lowermost positions in which the switch contacts are open. In this position the indicator 22 points to on the dial. if it is desired to set the timer to close the switch and open the latter after a predetermined period of time, the indicator is moved, thus rotating the shaft 17 and cam 21. This movement may take place in either direction as the movement is not transmitted to the motor owing to the frictional or slip connection between the gear 16 and the indicator shaft 17. The indicator is, of course, moved to indicate the proper interval of time during which it is desired that the switch be closed.

At the beginning of this movement, assuming that the indicator is moved in a clockwise direction, as shown in Fig. l, or a counterclockwise direction, as shown in Fig. 6, one of the arms of the spring 24 (the right-hand one as shown in Fig. 6) will be cammed outwardly from its normal position to permit the end 49 of the follower to ride upwardly on the gently inclined edge of the V-shaped recess 23 in the cam. As soon as this arm of the follower reaches the periphery of the cam, this displaced arm of the spring member 24 will be released and will return to its original position due to its inherent resilience. Raising the arm 49 of the follower to the position shown in Fig. 7 upon the periphery of the cam will raise the stirrup member 38 and elevate the contact member 34 to close the switch contacts 32 and 33. Thus this switch will be closed at the beginning of the setting movement and a continued movement of the cam member through substantially 360 degrees will continue to hold the follower arm in its elevated position and hold the switch closed.

Normally the switch contacts 32 and 33 will close the contact through the load circuit whatever it may be and, if the timer is operated by an electric motor, it will also close the circuit through the motor. The motor runs only in one direction and will rotate the indicator 20 in a counterclockwise direction, as shown in Fig. 1, regardless of the direction in which the indicator may have been originally moved to its set position. This will return the indicator to its starting position upon the expiration of the time period indicated on the dial.

When the indicator is returned to its 0 position, the cam 21 which rotates with the indicator will also be returned to its original position shown in Fig. 5. Upon return of the cam to this position the follower 49 will not ride down the incline of the side of the V-shaped recess 23 but will ride upon the arm 25 of the spring member 24 (which, of course, turns with the cam member) until the arm of the follower reaches the relatively narrow opening between the ends of the arms 25 and 26, at which time it will drop into the recess 23 between these arms. This sudden release of the cam follower will permit the spring 35 to open the switch with a snap action which would not be the case if the follower gradually descended into the recess 23 upon one of the inclined sides of the recess. Thus while one of the arms of the spring 24 (depending upon the direction the shaft 17 is turned) is permitted to spring away from its normal position to permit the arm 49 to ride up gradually out of the recess 23 without undue resistance when, at the end of the timed period, the parts are returned to their initial positions, the cam follower will drop suddenly into the recess and thus open the switch with a snap action.

It will be understood that, if it is desired, the indicator may be rotated in either direction by hand and thus the switch may be actuated manually, if desired. In such evelillt the timing or clock mechanism may be dispensed W1 When the switch mechanism is used in conjunction with timing mechanism, it may be found desirable to close and open the switch without employing the timing mechanism, and to this end means is provided to lock the timing mechanism against movement so that once the switch is closed it will remain closed until the cam is manually returned to its initial position.

For this purpose a second output shaft 52 (Fig. 4) is provided in the motor casing, which shaft is positively driven by the motor as is the shaft 14 previously described. Upon the end of this shaft is secured a toothed wheel 53 (Fig. 3) which is disposed within the casing 12. A latch member 54 is pivoted at 55 in the casing 12 and is provided with a laterally turned end 56 adapted to engage the teeth of the wheel 53 and prevent rotation of the motor and, therefore, prevent actuation of the indicator shaft 17. This latch member 54 is urged toward position to engage the wheel 53 by a spring 57 reacting at one end against a part of the casing 12 and engaging at its other end a lug 58 upon the latch member 54.

This latch member is also provided with a laterally extending lug 59 (Figs. 3, and 9) which, when the parts are in their position of rest, as shown in Fig. 3, is adapted to ride upon the periphery of the cam 21 and hold the latch member out of engagement with the teeth of the wheel 53.. As will be seen from Figs. 3 and 5 which show the parts in the position of rest, the lug 59 engages the periphery of the cam at a point adjacent the edge of the V-shaped recess 23 and, as the latch member is held in its inoperative position, the motor is free to move when energized. However, if the cam member 21 is turned to the left, as shown in Fig. 3, or to the right, as shown in Fig. 5, the lug 59 will drop into the recess 23 and the spring 57 will urge the latch member 54 into engagement with the teeth of the wheel 53 and prevent operation of the motor. Thus, if the indicator is turned through a small angle in the proper direction, it will move the cam 21 to a sulficient extent to close the contacts 32 and 33 and at the same time prevent movement of the motor so that the switch contacts will remain closed until the indicator is manually moved from this position.

As stated the normal or rest position of the parts is shown in front view in Fig. 3 and in rear view in Fig. 5. Upon the beginning of the rotation of the indicator shaft in a counterclockwise direction, as shown in Fig. 5, the parts take the position shown in Fig. 6 where the righthand portion of the spring 24 has been cammed outwardly to permit the arm 49 to ride up the incline of the notch 23.

Fig. 7 shows the position of the parts when the indicator has been set for a period of 15 minutes. The follower is now riding upon the periphery of the cam so as to hold the switch in closed position.

It will be noted that, as shown in Fig. 6, the switch may be closed upon a slight movement of the cam, but due to the lost-motion connection between the plunger 40 and the stirrup 38, the follower arm 49 is permitted an additional upward movement to reach the periphery of the cam, this movement further compressing the spring 41 without any additional movement of the switch plate 34.

In Fig. 9 of the drawings the parts are shown in position wherein the indicator is turned in a counterclockwise direction from its rest position shown in Fig. 1. Here the lug 59 has dropped into the recess 23 and the follower 49 has been raised to close the switch. The end 56 of the latch 54 is in engagement with the toothed wheel 53 so that rotation of the motor is prevented. The parts will remain in this position and the switch contacts remain closed until the indicator is turned in one direction or the other to rotate the cam' to position to raise the latch member from engagement with the toothed wheel 53. Alternatively, of course, the indicator may be turned in either direction to its 0 position to open the switch. It will also be noted that with the exception of the relatively small recess 23, the indicator is usable throughout the complete range of 360 degrees.

While I have shown and described one embodiment of my invention, it will be understood that it is not to be limited to all of the details shown, but is capable of modification and variation within the spirit of the invention and within the scope of the claims.

What I claim is:

1. A set and trip mechanism comprising a generally circular cam member having a recess in its periphery, a movably mounted cam follower having a portion engaging the periphery of the cam and adapted to be received in said recess, means for rotating said cam, a resilient member attached to the cam and having a movable free-end portion extending into said recess to be engaged by the follower when the cam is rotated, said member being deflected by the follower when the cam is rotated in one direction to permit the follower to ride on the periphery of the cam out of said recess and thereafter returning to its original position to form a continuation of the periphery of the cam and require the follower to drop from the end of said member into said recess when the cam is rotated in the other direction.

2. A set and trip mechanism as in claim 1 wherein said resilient member is provided with two arms having movable free-end portions extending into the cam recess from opposite sides thereof and symmetrically arranged with respect to the recess to permit actuation of the follower when the cam is rotated in either direction.

3. A set and trip mechanism as in claim 1 wherein said resilient member is secured to the cam at an intermediate portion of said member between its ends, and the free ends of said member are symmetrically arranged to extend into the cam recess from opposite sides thereof to permit actuation of the follower when the cam is rotated in either direction.

4. A set and trip mechanism comprising an essentially circular cam member having a recess in its periphery, means for rotatably mounting said member, a movable cam follower operating in engagement with the periphery of the cam and normally received in said recess, a resilient member carried by the cam and having a movable portion biased to extend into said recess by the resiliency of said member, said portion being engaged by the follower when the cam is rotated and deflected out of said recess to permit the follower to remain in contact with the periphery of the cam, and thereafter returning to its original position to provide an extension of the cam surface and permit the follower to ride over said portion and drop abruptly into said recess.

5. A set and trip mechanism comprising an essentially circular cam member having a recess in its periphery, means for rotatably mounting said member, a movable cam follower operating in engagement with the periphery of the cam, resilient members carried by the cam having movable portions biased, by the resiliency of said members, to extend into the recess from opposite sides thereof, said portions being adapted to be engaged by the follower when the cam is rotated and deflected out of said recess to permit the follower to remain in contact with the periphery of the cam, and said portions thereafter returning to said positions to provide an extension of the cam surface and permit the follower to ride over said portions whereby the mechanism may operate upon rotation of the cam in either direction.

6. Switch-actuating mechanism comprising a pair of contacts, a movable switch-closing member to engage said contacts, means operatively mounting said member, means for actuating said member comprising a rotatably mounted cam member, a cam follower engaging said cam member and adapted to actuate the movable switchclosing member, means associated with said cam member to effect snap action of said switch-closing member in a direction to open the switch, said cam being manually settable to predetermined positions to move the switchclosing member to switch-closing position, clock mechanism to rotate said cam in one direction after it has been set, and means controlled by said cam when set to one position to prevent rotation thereof by said clock mechanism when the contacts are engaged.

7. Switch-actuating mechanism comprising a pair of contacts, a movable switch-closing member to engage said contacts, means operatively mounting said member, means for actuating said member comprising a rotatably mounted cam member, a cam follower engaging said cam member and adapted to actuate the movable switchclosing member, means associated with said cam member to effect snap action of said switch-closing member in a direction to open the switch, said cam being manually settable to predetermined positions, clock mechanism to rotate said cam in one direction after it has been set, and means controlled by said cam when set to one position to prevent rotation thereof by said clock mechanism, said means comprising a second cam follower engaging the periphery of the cam member, and the latter having a peripheral recess in which an element of said second follower is received.

8. Switch-actuating mechanism comprising a pair of contacts, a movable switch-closing member to engage said contacts, means operatively mounting said member, means for actuating said member comprising a rotatably mounted cam member, a cam follower engaging said cam member and adapted to actuate the movable switchclosing member, means associated with said cam member to effect snap action of said switch-closing member in a direction to open the switch, said cam being manually settable to predetermined positions, clock mechanism to rotate said cam in one direction after it has been set, means controlled by said cam when set to one position to prevent rotation thereof by said clock mechanism, said means comprising a second cam follower engaging the periphery of the cam member, and the latter having a peripheral recess in which an element of said second fol lower is received, and said follower being adapted to engage a part of the clock mechanism and prevent movement thereof when said second follower element is received in said recess.

9. Switch-actuating mechanism comprising a pair of contacts, a switch-closing member, means for movably mounting said member for movement to and from a position to close said contacts, means for actuating said switch-closing member comprising a rotatably mounted cam having a recess in its periphery, a casing in which said cam member is mounted, a cam follower pivoted in the casing and having a part adapted to be received in said recess, said follower being adapted to engage said actuating means, a substantially U-shaped spring member car ried by said cam and having its free ends turned inwardly to project into said recess from opposite sides thereof, and said ends being spaced apart to receive said follower part therebetween.

l0. SWitchTactuating mechanism comprising a pair of contacts, a switch-closing member, means for movably mounting said member for movement to and from a position to close said contacts, means for actuating said switch-closing member comprising a rotatably mounted cam having a recess in its periphery, a casing in which said cam member is mounted, a cam follower pivoted in the casing and having a part adapted to be received in said recess, said follower being adapted to engage said actuating means, a substantially U-shaped spring member carried by said cam and having its free ends turned inwardly to project into said recess from opposite sides thereof, said ends being spaced apart to receive said follower part therebetween, and said actuating means comprising a stirrup engaged by the cam follower, a springpressed plunger mounted in said stirrup, and said plunger engaging said switch-closing member to move the latter to switch-closing position.

11. Switch-actuating mechanism comprising a pair of contacts, a switch-closing member, means for movably mounting said member for movement to and from a position to close said contacts, means for actuating said switch-closing member comprising a rotatably mounted cam having a recess in its periphery, a casing in which said cam member is mounted, a cam follower pivoted in the casing and having a part adapted to be received in said recess, said follower being adapted to engage said actuating means, a substantially U-shaped spring member carried by said cam and having its free ends turned inwardly to project into said recess from opposite sides thereof, said ends being spaced apart to receive said follower part therebetween, said actuating means comprising a stirrup engaged by the cam follower, a spring. pressed plunger mounted in said stirrup, said plunger engaging said switch-closing member to move the latter to switch-closing position, and spring means acting on said switch-closing member to urge it toward open position.

12. Switch-actuation mechanism comprising a pair of contacts, a switch-closing member adapted to close a circuit through said contacts, means for movably mounting said member, a rotatably mounted cam member having a recess in its periphery, a cam follower engaging the (periphery of the cam and adapted to be received in said recess, said follower being connected to said switchclosing member to actuate the same, said recess having inclined side walls, a resilient member secured to said cam member projection into said recess from each side thereof to extend over the adjacent wall of the recess, the adjacent portions of said resilient members being spaced apart over said recess to permit the follower to drop between them into said recess, and said resilient members being cammed out of said recess by said follower when the latter moves out of said recess upon rotation of the cam member.

13. Switch-actuating mechanism comprising a switch means, a switch-closing member, means for movably mounting said member for movement to and from a position to close said switch means, means for actuating said switch-closing member comprising a rotatably mounted cam having a recess in its periphery, a cam follower having a part adapted to be received in said recess, said follower being adapted to engage said actuating means and move it in position to close the switch means, a bowed spring member secured at an intermediate point to said cam and having free ends projecting into said recess from opposite sides thereof, said ends being spaced apart to receive said followed part therebetween and being adapted to be deflected out of said recess, when the cam is rotated, to permit the follower to remain in contact with the periphery of the cam and move thereon out of the recess, and the ends of said spring member thereafter returning to their original positions to provide extensions of the cam surface upon which the follower rides and from which it drops abruptly into said recess.

References Cited in the file of this patent UNITED STATES PATENTS 1,831,605 Porter -e Nov. 10, 1931 2,289,643 Furnas et a1 July 14, 19.42 2,528,841 Morrison et al. Nov. 7, 1950 2,670,039 Burkholder Feb. 23, 1954 2,769,099 Pcterlik et al. Oct. 30, 1956 2,776,009 Tamburr -2 Ian. 1, 1957 2,778,418 Laviana Jan. 22, 1957

Images