US2728822A - Switch mechanism - Google Patents

Description

Dec. 27, 1955 STOLLE ET AL 2,728,822

SWITCH MECHANISM Filed June 14, 1954 2 Sheets-Sheet 1 BY 25 5'? 5m Dec. 27, 1955 D. STOLLE ETAL 2,728,822

SWITCH MECHANISM Filed June 14, 1954 2 Sheets-Sheet 2 United States Patent SWITCH MECHANISM Anthony D. Stalls and Robert B. Ellis, Chicago, lll., assignors to International Register Company, Chicago, Ill., a corporation of Illinois Application June 14, 1954, Serial No. 436,548 6 Claims. (Cl. 206-38) Our present invention relates generally to switch mechanisms, and, more specifically, is directed to time switch mechanisms.

it is an object of our present invention to provide a time switch mechanism wherein an electrical circuit may be established between two non-adjacent switch arms for a predetermined interval of time.

Briefly, in accomplishing the foregoing object, we provide a switch mechanism comprising a pair of non-adjacent switch arm means, and current conducting means carried by a power driven revolvable member. The current conducting means in one range of rotation of the revolvable member serves to engage simultaneously the pair of switch arm means for electrically interconnecting the latter.

The mechanism of our present invention for electrically interconnecting two non-adjacent switch arms is particularly adapted for use in the time switch mechanisms which are disclosed and claimed in the copending application of William P. Gallagher, Anthony D. Stolle, and Robert B. Ellis, Serial. No. 393,802, filed November 23, 1953.

The time switch mechanism of the aforedescribed copending application comprises a cam having a track with an abrupt radial recess. The cam is rotated by power driven gear reduction means. in addition, the switch cornprises a primary switch arm which is mounted for movement into and out of engagement with a contact for establishing and di'sestablishing an electrical circuit. The primary switch arm is provided with a pivotally floating cam follower which is en ageable with the cam track for urging the switch arm into engagement with the switch contact. The floating cam follower is receivable in the cam track recess, and upon leaving the cam track and entering the recess, instantaneously flips or pivots to effeet a quick break away of the primary switch arm from engagement with the contact. By employing the combination of elements just described, arcing at the contact is eliminated and precise timing may be obtained.

it is a further object of our present invention to provide a switch mechanism of the general character noted wherein an auxiliary circuit may be established momentarily at a predetermined point in the timing cycle without interfering with the operation of the primary circuit means of the switch mechanism.

In accomplishing the latter object, we specifically pivotally mount lever means intermediate of its ends to the revolvable cam and secure insulating means to the lever means. T he insulating means has a portion spaced from the end of the terminus of the lever means and projects beyond the edge of the latter alongside of the cam track recess. When the cam follower moves into the cam track recess, it engages the insulating means and pivots the other end of the lever means into engagement with an auxiliary spring metal switch arm thereby preloading the latter through fiexure so that a spring force is maintained on the lever means. The cam follower upon further rotation of the cam moves oil of the insulating means, at

which time the preloaded auxiliary switch arm serves to snap pivot the adjacent end of the lever means toward the follower so as to insure a quick make of engagement between these elements, while the other end of the lever means remains in engagement with the auxiliary switch arm, whereupon the primary and auxiliary switch arms become electrically interconnected. Upon still further rotation of the cam, the cam follower moves out of engagement with the lever means, at which time the preloaded auxiliary switch arm serves to snap pivot the lever means up and away from the follower so as to insure a quick break of engagement between these elements, whereupon the electrical interconnection. between the primary and auxiliary switch arms is interrupted. During the interval of time that the secondary circuit is closed and opened the primary switch arm remains in engagement with the contact. Thus operation of the auxiliary circuit does not interfere with the operation of the primary circuit.

Now, in order to acquaint those skilled in the art with the manner of constructing and using time switches in accordance with the principles of our present invention, we shall describe in connection with the accompanying drawings a preferred embodiment of our present invention.

In the drawings:

Figure 1 is an exploded view of the time switch mechanism of our present invention;

Figure 2 is a front elevational view of the time switch mechanism of Figure 1, with the cover member being broken away; and

Figures 3 through 11 illustrate various sequences of steps in the operation of the time switch mechanism of Figure 1.

Referring now to Figures 1 and 2, there is shown the time switch mechanism of our present invention, indicated generally by the reference numeral 10, which comprises a generally rectangular insulating member 12 that provides support for the various elements of the switch mechanisms.

Formed in the upper half of the member 12 are spaced apart transverse rectangular apertures 14, 16 and 13, which are arranged in ascending stepped relation from left to right. An additional diagonal, rectangular aperture 19 is formed in the member 12 spaced to the right of the aperture 18. Staked or positioned in the apertures 14, 16, 18 and 19, respectively, are metallic terminal post members 20, 22, 24 and 25. The process by which the terminal post members 20, 22, 24 and 25 are staked to the mounting 12 is disclosed and claimed in the co-pending application of William P. Gallagher, Anthony D. Stolle, and Paul G. Bielik, Serial No. 366,842, filed July 8, 1953. The rear ends of the posts 20, 22, 24 and 25, that project through the member 12, are adapted to have suitable connection with various electrical devices, the sequences of operation of which it is desired to have timed.

Secured, as by riveting, to the forward ends of the posts 20, 22 and 25 are the one ends of metallic switch arms 26, 28 and 30. The other ends of the switch arms 26 and 28 have, respectively, mounted thereto metallic contacts 32 and 34, the latter of which cooperates with a metallic contact 36 secured to the terminal post 24. Movement of the switch arm 28 in one direction is limited by a pin stop 38. The switch arms 26, 28 and 30 are preferably formed of spring material so that they are free to flex during operation of the time switch mechanism.

Movement of the switch arms 26 and 28 is adapted to be effected by means of a non-metallic revolvable member or cam 40 mounted on a shaft 42, which is journaled, at one end, in a central aperture 44 formed in the mounting member 12, and, at the other end, in a central aperture 46 formed in a cover member 48 having arm members 50. In the assembly of the switch mechanism of our present invention, lugs 52, which are formed at the ends of the arms 50 of the cover member 48, are inserted through rectangular openings 54 formed at the sides of the mounting member 12 and are then bent or twisted so as to lock the cover 48 in position. A radial recess, having two steps 56 and 58, is formed in the peripheral track 60 of the aforedescribed revolvable member or cam 40.

Secured to the shaft 42, with the cam 40, is a gear 62 which has meshing engagement with a pinion 64 that projects through an aperture 66 formed in the mounting member 12. The gear 64 is drivingly connected through reduction gearing with a slow speed synchronous electric motor, the latter assembly being indicated generally by the reference numeral 68. The electric motor and reduction gearing unit 68 is secured by screws 70, threaded into openings 71, to the mounting member 12, with the electric motor being adapted to be placed in connection with an electric power source through lines 72 and 74.

Associated with the switch arm 26 is a metallic floating C-shaped cam follower 76 which has a body portion 78 and arm portions 88. The switch arm 26, intermediate of the ends thereof, is formed at its opposite edges with spaced flanges 82 that project at right angles therefrom and toward the cam 40. Each flange 82 is formed in two parts which define a substantially V-shaped recess 84.

The V-shaped recesses 84 floatingly and pivotally receive the G-shaped cam follower 76 when the elements of the switch mechanism are in assembled relation, as shown in Figure 2. The arm portions 80 of the follower 76 partially envelop the switch arm 26 and intersect the plane of the latter so as to serve to limit endwise movement of the follower 76 relative to the arm 26.

The body portion 78 of the follower 76 is adapted to engage the cam track 60 for flexing the switch arms 26 and 28 away from the cam so as to thereby urge the contact 32 into engagement with the contact 34 and the contact 34 into engagement with the contact 36.

The floating cam follower 76 is receivable in the stepped cam track recess to effect a quick break away of the contact 34 from engagement with the contact 36 and the contact 32 from engagement with the contact 34.

The mechanism for electrically interconnecting the non-adjacent switch arms 26 and for a predetermined interval of time comprises current conducting means such as a metallic lever 86 pivotally mounted intermediate of its ends at 88 to the cam 40. Insulating means such as a member 90 is secured to one end of the lever 86. The insulating member 90 has a portion 92 which is spaced from the adjacent end terminus of the lever 86 and projects beyond the edge of the latter alongside of the step 56 of the cam track recess. The lever 86 and insulating means 90 constitute lever mechanism the ends of which simultaneously engage portions of the switch arms 26 and 30 in one range of rotation of the cam 40. The insulating means 90 through a portion of said one range of rotation serves to prevent electrical interconnection of the switch arms 26 and 30; the lever 86, however, through another portion of said one range of rotation serves to electrically interconnect the switch arms.

Since the cam follower 76 is fioatingly mounted and has limited pivotal movement relative to the switch arm 26, the follower 76, when moved to the cam track 60, is conditioned to be pivoted so as to point in the direction that the cam is to be power rotated. For example, if, to institute a timed cycle of operation, the cam 49 is manually rotated counter-clockwise, from the position shown in Figures 2 and 3, the follower 76 will initially pivot clockwise and will ascend the right end of the step 58 of the cam track recess to the landing of the step 56 as shown in Figure 4. During this manual counter-clockwise rotation of the cam 48, which is permitted because of slippage of a friction clutch employed in the timer motor assembly 68, the contact 32 is moved into engagement with the contact 3 for completing an electrical circuit between the terminal posts 28 and 22 and for establishing energization of the timer motor assembly 68.

During further manual counter-clockwise rotation of the cam 40, the follower 76 will engage in sequence the projecting end terminus of the lever 86 and the insulating member for pivoting the latter downwardly to the position shown in Figure 5. At the same time, the follower 76 will snap counter-clockwise to the solid line position shown in Figure 5 so as to point in the direction that the cam 40 is to be power rotated. The snap action is obtained by offsetting the pivotal axis of the follower 76 from the axis of rotation of the cam 48.

Still further manual counter-clockwise rotation of the cam 40 first causes the follower 76 to pivot clockwise to the position shown in dotted lines in Figure 5 so as to facilitate its travel up the right incline of the step 56, and then, as the follower '76 rides up the incline and reaches the landing of the cam track 66, effects a snap pivot of the follower counter-clockwise to the position shown in Figure 6. At this point, the contact 34 is moved into engagement with the contact 36 for completing an electrical circuit between the terminal posts 22 and 24. Upon completion of manual rotation of the cam, the motor assembly 68 will begin to rotate the cam clockwise.

The cam 40 may be rotated manually in a clockwise direction for instituting a timed cycle of operation. Upon manual rotation of the cam 40 in a clockwise direction from the position shown in Figure 3, the follower 76 initially tends to assume substantially the same angle as the left end of the step 58 of the cam track recess, thus facilitating travel of the follower 76 up the incline to the cam track proper.

As the follower 76 rides up the incline, the switch arm 26 is flexed and the contact 32 is moved into engagement with contact 34 for completing an electrical circuit between the terminal posts 20 and 22 and establishing energization of the timer motor assembly 68. Continued manual rotation of the cam in a clockwise direction moves the follower 76 to the cam track 60 at which point, as shown in Figure 7, the contact 34 is moved into engagement with the contact 36 for completing an electrical circuit between the terminal posts 22 and 24. After the cam follower 76 has been moved to the position shown in Figure 7, the motor assembly 68 takes over clockwise rotation of the cam 48.

It should be pointed out that irrespective of the direction of rotation for manually pre-setting the timer, the above described steps are effected in a continuous smooth manner. It will further be understood by those skilled in the art that the length of the timed cycle will depend upon the number of degrees that the cam 40 must be power rotated to dispose the cam track follower 76 in the cam track recess after the timer mechanism has been preset. As the cam 40 is rotated in a clockwise direction by the motor assembly 68, the follower 76 remains inclined downwardly toward the right, as viewed in Figure 6, thereby maintaining the drag on the cam 40, and attendant wear, at a minimum.

The timed cycle is completed when the follower '76 enters the cam track recess. The follower 76, upon leaving the cam track 60 and entering the step 56 of the cam track recess, first drops to the position shown in Figure 8 whereupon a quick break of engagement between the contacts 34 and 36 is effected. In addition, the follower 76 when moving into the step 56 engages the insulating member 90 for pivoting the lever 86 counter-clockwise about its pivot point 88. This action, as will be observed in Figure 8, causes the end of the lever 86 opposite the insulating member 90 to pivot outwardly against the switch arm 30 thereby preloading the latter through flexure so that a clockwise spring force is maintained on the lever 86 while the follower 76 is in engagement with either the insulating member 90 or the end terminus of the lever 86 Further rotation of the cam 40 causes the follower 76 to move along the insulating member 90 toward the adjacent end terminus of the lever 86. When the follower 76 moves oil of the insulating member 90, the preloaded switch arm 39 serves to snap pivot the end terminus of the lever 86 toward the follower so as to insure a quick make of engagement between these elements, while the opposite end of the lever remains in engagement with the switch arm 30. At this point, an electrical interconnection is effected between the switch arms 26 and 30 through the follower 76 and the lever 86 and an auxiliary electrical circuit is established through the timer mechanism.

Still further rotation of the cam 40 causes the cam follower 76 to move out of engagement with the end terminus of the lever 86, at which time the preloaded switch arm 30 serves to snap pivot the end of the lever radially outwardly and away from the follower so as to insure a quick break of engagement between these elements, whereupon the electrical interconnection between the switch arms 26 and 30 is interrupted and the auxiliary circuit broken. During the interval of time that the auxiliary or secondary circuit is closed and opened, the primary circuit embodying the contacts 32 and 34 remains closed. Thus operation of the auxiliary circuit does not interfere with the operation of the primary circuit. In the final period of rotation of the cam 40, the follower 76 is caused to leave the step 56 and enter the step 58 of the cam track recess, at which time the follower pivots instantaneously for permitting the latter to drop quickly for effecting a quick break of engagement between the contacts 32 and 34.

The above described cycles of operation may be repeated as desired. It will be understood by those skilled in the art that the cycles of operation may be varied by changing the arcuate length of the steps of the cam track recess, or by increasing the number of recesses about the periphery of the cam, or by varying the length of the end terminus of the lever 86 that is exposed beyond the insulating member 90.

Now, while we have shown and described what we believe to be a preferred embodiment of our present invention, it will be understood by those skilled in the art that various rearrangements and modifications may be made therein without departing from the spirit and scope of our present invention.

We claim:

1. In a switch assembly, the combination of a revolvable member, lever mechanism including a lever pivotally mounted intermediate of its ends to said revolvable member, said lever mechanism also including insulating means secured to said lever, said insulating means having a portion spaced from the end terminus of said lever and projecting beyond the edge of the latter, first switch arm means engageable by said lever mechanism, second switch arm means engageable by said lever mechanism, the end portions of said lever mechanism in one range of rotation of said revolvable member serving respectively to engage simultaneously said first and second switch arm means, said insulating means through a portion of said one range of rotation serving to prevent electrical interconnection of said first and second switch arm means, and said lever through another portion of said one range of rotation serving to electrically interconnect said first and second switch arm means.

2. In a switch assembly, the combination of a revolvable member, a lever pivotally mounted intermediate of its ends to said revolvable member, insulating means secured to said lever, said insulating means having a portion spaced from the end terminus of said lever and projecting beyond the edge of the latter, first switch arm means associated with said revolvable member, second switch arm means associated with said revolvable member, said first switch arm means in one range of rotation of said revolvable member engaging said insulating member for pivoting the other end of said lever into engagement with said second switch arm means, and said first switch arm means upon rotation of said revolvable mem ber moving from said insulatnig member to the adjacent end of said lever means while the other end of said lever means remains in engagement with said second switch arm means whereupon said first and second switch arm means are electrically interconnected.

3. In a switch assembly, the combination of a revolvable member, a lever pivotally mounted intermediate of its ends to said revolvable member, insulating means secured to said lever, said insulating means having a por tion spaced from the end terminus of said lever and projecting beyond the edge of the latter, first switch arm means associated with said revolvable member, a float ing cam follower associated with said first switch arm means, second switch arm means associated with said revolvable member, said floating cam follower in one range of rotation of said revolvable member engaging said insulating member for pivoting the other end of said lever into engagement with said second switch arm means, and said floating cam follower upon rotation of said revolvable member moving from said insulating member to the adjacent end of said lever means while the other end of said lever means remains in engagement with said second switch arm means whereupon said first and second switch arm means are electrically interconnected.

4. In a switch assembly, the combination of a revolvable cam having a track with an abrupt radial recess, a lever pivotally mounted intermediate of its ends to said revolvable member, insulating means secured to said lever, said insulating means having a portion spaced from the end terminus of said lever and projecting beyond the edge of the latter alongside of said cam track recess, a first switch arm associated with said cam, a cam follower associated with said first switch arm and engageable with said cam track, a second switch arm associated with said cam, said follower being receivable in said earn track recess and engaging said insulating member for pivoting the other end of said lever into engagement with said second switch arm, and said cam follower upon rotation of said cam moving from said insulating member to the adjacent end of said lever while the other end of said lever remains in engagement with said second switch arm whereupon said first and second switch arms are electrically interconnected.

5. In a switch assembly, the combination of a revolvable cam having a track with an abrupt radial recess, first switch arm means mounted for movement into and out of engagement with a contact, a floating cam follower associated with said first switch arm means and engageable with said cam forurging said first switch arm means into engagement with said contact for establishing a primary circuit, lever means pivotally mounted intermediate of its ends to said cam, insulating means secured to said lever means, said insulating means having a portion spaced from the end terminus of said lever means and projecting beyond the edge of the latter alongside of said cam track recess, second spring metal switch arm means associated with said cam, said cam follower upon rotation of said cam being receivable in said cam track recess, said cam follower when moving into said cam track recess being engageable with said insulating means for pivoting the other end of said lever means into engagement with said second switch arm means thereby preloading the latter through fiexure so that a spring force is maintained on the lever means, said cam follower upon further rotation of said cam moving off of said insulating means at which time the preloaded second switch arm means serves to snap pivot the adjacent end of said lever means toward said follower so as to insure a quick make of engagement betwcenrthese elements while the other end of .said lever means remains in engagement with said second switch arm means whereupon said first and second switch arm means become electrically interconnected for establishing a secondary circuit, said cam follower upon still further rotation of said cam moving outof engagementwith said lever means at which time the preloaded second switch arm means serves to snap pivot the lever means up and away from the follower so as to insure aquick hreakof engagement between these elements whereupon the electrical interconnection between said first and second switch arm means is interrupted, and said secondary circuit being closed and opened without interfering with the operation of the primary circuit.

6. in a switch assembly, the combination of a revolvable cam having a track with an abrupt radial recess, first switch arm means mounted for movement into and out of engagement with a contact, second switch arm means mounted for movement into and out of engagement with said second switch arm means, a cam follower associated with said second switch arm means and engageable with said cam track for urging said second switch arm means into'engagement with said first switch arm means and said first switch arm means into engagement with said contact, lever means pivotally mounted intermediate of its ends to said cam, insulating means secured to said lever means, said insulating means having a portion spaced from the end terminus of said lever means and projecting beyond the edge-of the latter alongside of said cam track recess, thirdswitch arm means associated with said cam, said cam'follower upon rotation of said cam being receivable in said cam track recess to eiiect a quick break away of said first switch arm means from engagement with said contact and said second switch arm means from engagement with said first switch arm means, said cam follower when moving into said earn track recess being engageable with said insulating means for pivoting the other end of said lever means into engagement with said third switch means, said cam follower upon further rotation of said cam moving from said insulating means to the adjacent end of said lever means while the other end of said lever means remains in engagement with said third switch armmeans whereupon said second and third switch arrn means become electrically interconnected, and said cam follower upon stillfurther rotation of said cam moving out of engagement with said lever means whereby the electricalinterconnection between said second and thirdswitch arm means is interrupted.

References Cited in the file of this patent UNITED STATES PATENTS l Stolz May 14, 1901

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