US2951130A - Rotary switch - Google Patents

Description

Aug. 30, 1960 H. F. MASON 2,951,130

ROTARY SWITCH Filed May 5, 1959 6 FIG. 1.

INVENTOR HOWARD E MASON BY H/S ATTOEA/b'YS HARE/5, K/ECH, Russell. (2/1150 Unite ROTARY swrrcn Filed May 5, 1959, Ser. No. 811,091

'10 Claims. (Cl. 200-457) The present invention relates in general to rotary switches and, more particularly, to a rotary switch which operates with a snap action, produced by energy stored in a spring or spring system, to make and break contact quickly so as to minimize arcing, which operates in a positive manner in that the movable contact snaps from one operative position to another without any possibility of hesitating between such positions, which operates in this manner irrespective of how the switch may be manipulated by its operator and irrespective of vibration, which provides a positive feel? sothat, when the switch is operated manually, the operator can readily determine that the switch has advanced from one'operative position to another, and the like.

Still more particularly, the invention relates to a rotary switch similar to those of my Patents Nos. 2,831,073 and 2,831,082, both granted April 15, 1958, a general object of the invention to provide a switch which is an improvement on those disclosed in such patents.

Considering therotary switch of the present invention in a general way, it includes: an arcuate contact path having a center of curvature and having circumferentially spaced recesses therein .and having thereon at least one stationary contact in which one of the recesses is formed, there normally, but not necessarily, being a stationary contact at each recess; a contact carrier movable about the center of curvature along, a carrier path adjacent and concentric with the contact path; a roller contact carried by the contact carrier, and engaging and rollable along the contact path and receivable -in each of the recesses therein; resilient means engaging the roller contact and biasing same into engagement with the contact path; actuating means for moving the contact carrier along the carrier path; and means providing a resilient lost-motion connection between the actuating means and the contact carrier for transmitting rotation of the actuating means to the contact carrier after limited rotation of the actuating means, such lost-motion con nectionresulting in energy storage which causes the roller contact to snap from one recess to the next when the roller contact is forced out of the first recess after using up the lost motion between the actuating means and the contact carrier. a

A primary object of the invention is to provide a rotary switch of the foregoing nature having cam means on the contact carrier for moving the roller contact radially out of arecess-in which it is disposed in response-to movement of the contact carrier along the carrier path by the actuating means, such cam means overcoming at least partially the resilient means biasing, the roller contact into engagement with the contact path.

The foregoing is an importantfeature since it peratent contact pressure can be quite high when the roller contact is disposed in one of the recesses, which is desirable but this high contact pressure is reduced by the cam means when the roller contact is to be moved out of such recess and into the next one, thereby facilitating operation of the switch.

Another object of the invention is to provide the con tact carrier with a cam surface inclined at an acute angle to the contact path and adapted to move the roller contact radially out of a recess in which it is disposed in response to movement of the contact carrier along the carrier path.

Another object is to provide the contact carrier with two cam surfaces converging toward and inclined at acute angles to the contact path, one of these cam surfaces camming the roller contact out of the recess in which it is disposed in response to movement of the contact carrier in one direction, and the other cam surface achieving the same result in response to movement of the contact carrier in the opposite direction, thereby providing a cam means which operates in both directions of. movement of the contact carrier.

A further object is to provide a construction wherein the roller contact has an axle which is engageable by the cam surfaces mentioned and which is engaged by the resilient means for biasing the roller contact into engagement with the contact path. I

Still another object is to provide a construction wherein the resilient means for biasing the roller contact comprises torsion springs each having an arm engaging the contactcarrier and another arm engaging the axle of the roller contact.

V The foregoing objects, advantages, features and results of the present invention, together with various other objects, advantages, features and results thereof which will be evident to those skilled in the rotary switch art in the light of this disclosure, may be achieved with the exemplary embodiment described in detail hereinafter and illustrated in the accompanying drawing, in which:

Figs. 1 to 5 are semidiagrammatic, transverse sectional views of a rotary switch embodying theinvention and showing various components thereof in successive operatmits avery high contact pressure between theroller .con-

ing positions; and

Fig. 6 is a longitudinal sectional view taken along the arrowed line 66 of Fig. 1.

In the drawing, the numeral 10 designates a rotary switch of the invention which is more properly termed a toggle switch since its operating range is only a small segment of a circle. However, it will be understood that the operating range of the switch 10 may be increased up to and including 360, as shown in my aforementioned patents. Also, various of the structural fea tures disclosed in such, Patents may be incorporated in the switch 10, it being understood that much of the structure of the switch 10 is illustrated semidiagrammatically for convenience.

Considering the switch 10 in more detail, it includes a case or housing 12 which provides anarcuate contact path 14 having its center of curvature at 16. The con: tact path 14 is provided with arcuate recesses 18, 20 and 22 therein which are directed radially inwardly toward the center of curvature 16. In the particular constructionillustrated, the switch 10 includes a number ofstationary contacts equal to the number of recesses, the stationary contacts respectively being designated by the numerals 24, 26 and 28 and respectively having the recesses 18, 20 and 22 formed therein. However, it will be understood that not all of the recessesneed to be formed in stationary contacts. For example, if one of the recesses 18, 20 and 22 merely represents an off position, the corresponding stationary contact may be omitted. Y

The stationary contacts 24, 26 and 28 are electrically insulated from each other, as by embedding them in electrical insulating material. In the particular construction illustrated, the entire housing 12 is formed of electrical insulating material and the stationary contacts 24, 26 and 28 are embedded therein. As wi-llbe apparent, the contact path 14 is formed partially by the stationary contacts 24, 26 and 28 and partially by the electrical insulating material separating these contacts from each other.

As best shown in Fig. 6 of the drawing, each of the stationary contacts 24, 26 and 28 includes two longitudinally spaced stationary contact elements electrically insu-lated from each other and adapted to be bridged by a roller contact 3% reliable along the contact path 14 and receivable in each of the recesses 18, 20 and 22 therein. In the particular construction illustrated, the roller contact 30 is similar to the roller contact 32 of my Patent No. 2,831,073 and includes two rollercontact elements respectively engageable with the stationary contact elements of each of the stationary contacts 24, 26 and 28 and interconnected by an axle 32 which projects beyond the ends of the roller contact. However, it will be understood that the roller contact 30 may, if desired, have the construction of the roller contact 25 of my Patent No. 2,831,082. This latter construction has the advantage that the stationary contacts 24, 26 and 28 and the electrical insulating material therebetween may be out of alignment to prevent the roller contact 30 from tracking metal from the stationary contacts onto the intervening electrical insulating material.

The roller contact 30 is housed in a contact carrier 34 having side walls 36 respectively provided with notches or slots 38 respectively receiving the ends of the axle 32. The inner ends of the slots 38 communicate with triangular openings 40 respectively formed in the side walls 36 of the contact carrier 34 and respectively adapted to receive the ends of the axle 32. Eachtriangular opening 40 is provided with two cam edges or surfaces 42 and 43 converging toward and making acute angles with the contact path 14 and. engageable with the corresponding end of the axle 32. The cam surfaces 42 and 43 constitute a cam means for moving the roller contact 30 out of one of the recesses 18, 20 and 22 in which it is disposed, as discussed in more detail hereinafter. I

The roller contact 30 is biased into engagement with the contact path 14 andinto the recesses 18, 20 and 22 therein by a resilient means which is shown as comprising two torsion springs 44 respectively coiled around pins 46 on the contact carrier 34 and each having an arm 48 engaging the contact carrier and another arm 50 engaging the axle 32. In the particular construction illustrated, there are two of the springs 44 and they engage the axle 32 intermediate the roller contact elements forming the roller contact 30. However, it will be understood that if the roller contact structure 25 of my Patent No. 2,831,082 is,nsed, there may be four of the springs 44, two engaging each end of the roller contact axle.

The switch includes an actuating means 52 shown as comprising a lever 54 having thereon a ball 56 the center of which coincides with the center of curvature 16 and which is disposed in a diagrammatically-shown ball socket 58 carried by the housing 12. It will be understood that this represents merely one way of obtaining rotary motion about the center of curvature 16 and that such rotary motion may be achieved in other ways. For example, a shaft, not shown, may be substituted for the ball 56, particularly where 360 rotation of the roller contact 30 is desired. The lever 54 is connected to the contact carrier 34 by a lost-motion connection 60, which provides a range of relative rocking movement between the lever and the contact carrier at least approaching the spacing of the stationary contacts 24, 26 and 28 so that once movement of the roller contact 30 from one recess to the next begins, such movement is completed with little or no further movement of the lever 54 to provide a positive action which cannot be interfered with by the operator of the switch 10. Means 62 for limiting the relative rocking movement between the lever 54 and the contact carrier 34 is provided.

Considering the lost-motion connection 60 in more detail, mounted on the inner end of the lever '54 within the housing 12 is an actuator 64 engaging the contact carrier 34 through two tongue-and-groove connections which form the lost-motion connection 60. More specifically, in the particular construction illustrated, the actuator 64 is provided therein with two parallel grooves 66 and 68 which extend transversely of the contact path 14 and which receive complementary tongues or ribs 70 and 72, respectively, on the contact carrier 34. The means 62 for limiting relative rocking motion between the actuator 64 and the contact carrier 34 comprises stops or kickers 74 and 76 respectively engageable with the ends of the contact carrier 34. 1

Considering the operation of the invention, it will be assumed that the components of the switch 10 are in the positions shown in Fig. 1 of the drawing and that the rollercontact 30 is to be moved from the recess 20 into the recess 22. This is accomplished by a leftward force applied to the outer end of the lever 54, which force produces the following action.

First, the actuator 64 "and the contact carrier 34 rock relative to each other about the tongue-and-grooveconnection provided by the tongue 70 and the groove 66 into the positions shown in Fig. 2. Such relative rocking of the actuator 64 and the contact carrier 34 has resulted in engagement of the kicker 74 with the left end of the contact carrier 34. This relative rocking has also resulted in engagement of the ends of the axle 32 with the cam surfaces 42, the stress in the springs 44 having been increased to some extent as the foregoing takes place.

Turning nowto Fig. 3 of the drawing, further leftw ard movement of the outer end of the lever 54 causes the kicker 74 to move the cont-act carrier 34 toward the right. When this happens, the cam surfaces 42 acting on the ends of the axle 32 lift the roller contact 30 out of the recess 20 and onto the raceway between the recesses 20 and 22 in opposition to the action of the springs 44. 7

Once the roller contact 30 is on the raceway between the recesses 20 and 22, as shown in Fig. 4, the springs 44 start to rock the contact carrier 34 back into its original position relative to the actuator 64. This restoring action on the contact carrier 34 by the energy stored in the springs 44 causes the roller contact 30 to roll along the raceway between the recesses 20 and 22 and into the recess 22 extremely rapidly. This has the eifect of minimizing arcing, and also has the eiiect of insuring that once the roller contact 30 leaves the recess 20, it will move all the way into the recess 22 irrespective of any subsequent manipulation of the lever 54.

It will be apparent that the switch 10 operates in the same manner when the roller contact 30 moves from the recess 18 to the recess 20. The switch operates in a similar manner when the roller contact 30 moves from the recess 22 into the recess 20, or from the recess 20 into the recess 18, except that the kicker 76 and the cam surfaces 43 operate, instead of the kicker 74 and the cam surfaces 42.

The most important feature of the invention is that the cam means provided by the cam surfaces 42 and 43 lifts the roller contact 30 out of each of the recesses 18, 20 and 22 in opposition to the action of the springs 44, thereby reducing the operating force which would otherwise be required'to kick the roller contact out of the recess in which it is disposed. Consequently, for the same operating force, springs 44 producing greater spring forces may be utilized to attain the maximum possible contact pressure between the roller contact 30 and the stationary contacts 24, 26 and 28. Thus, the invention has the efiect of maximizing the contact pressure while minimizing the operating force required.

Although an exemplary embodiment has been disclosed herein for purposes of illustration, it will be understood that various changes, modifications and substitutions may be incorporated in such embodiment without departing from the spirit of the invention as defined by the claims which follow.

I claim:

1. In a rotary switch, the combination of: an arcuate contact path having a center of curvature and having circumferentially spaced recesses therein and having thereon at least one stationary contact in which one of said recesses is formed; a contact carrier movable about said center of curvature along a carrier path adjacent and concentric with said contact path; actuating means movable about said center of curvature for moving said contact carrier along said carrier path; a roller contact carried by said contact carrier and engaging and rollable along said contact path and receivable in each of said recesses; means, including resilient means, acting on said roller contact for biasing said roller contact into engagement with said contact path; and cam means on said contact carrier and engageable with said roller contact for moving said roller contact out of one of said recesses in which it is disposed in response to movement of said contact carrier along said carrier path by said actuating means.

2. In a rotary switch, the combination of: an arcuate contact path having a center of curvature and having circumferentially spaced recesses therein and having thereon at least one stationary contact in which one of said recesses is formed; a contact carrier movable about said center of curvature along a carrier path adjacent and concentric with said contact path; actuating means movable about said center of curvature for moving said contact carrier along said carrier path; a roller contact carried by said contact carrier and engaging and rollable along said contact path and receivable in each of said recesses, said roller contact having an axle; means, including resilient means, acting on said axle for biasing said roller contact into engagement with said contact path; and cam means on said contact carrier and engageable with said axle for moving said roller contact out of one of said recesses in which it is disposed in response to movement of said contact carrier along said carrier path by said actuating means.

3. In a rotary switch, the combination of: an arcuate contact path having a center of curvature and having circumferentially spaced recesses therein and having thereon at least one stationary contact in which one of said recesses is formed; a roller contact engaging and rollable along said contact path and receivable in each of said recesses, said roller contact having an axle; a contact carrier for said roller contact movable about said center of curvature along a carrier path concentric with and adjacent said contact path, said contact carrier having thereon cam means engageable with said axle for moving said roller contact radially out of one of said recesses in which it is disposed in response to movement of said contact carrier along said contact path, said cam means including a cam surface engageable with said axle and inclined at an acute angle to said contact path; means, including resilient means, acting on said contact carrier and said axle for biasing said roller contact into engagement with said contact path and into one of said recesses in which it is disposed in opposition to the action of said cam means; and actuating means movable about said center of curvature for moving said contact carrier along said carrier path.

' 4. In a rotary switch, the combination of: an arcuate contact path having a center of curvature and having circumferentially spaced recesses therein and having thereon at least one stationary contact in which one of said recesses is formed; a roller contact engaging and rollable along said contact path and receivable in each" of said recesses, said roller contact having an axle; a contact carrier for said roller contact movable about said center of curvature along a carrier path concentric with and adjacent said contact path, said contact carrier having thereon cam means engageable with said axle for moving said roller contact radially out of one of said recesses which it is disposed in response to movement of said contact carrier along said contact path, said cam means including two inclined cam surfaces which converge toward and make acute angles with said path and which are selectively engageable with said axle; means, including resilient means, acting on said contact carrier and said axle for biasing said roller contact into engagement with said contact path and into one of said recesses in which it is disposed in opposition to the action of said cam means; and actuating means movable about said center of curvature for moving said contact carrier along said carrier path.

5. In a rotary switch, the combination of: an arcuate contact path having a center of curvature and having circumferentially spaced recesses therein and having thereon at least one stationary contact in which one of said recesses'is formed; a roller contact engaging and rollable along said contact path and receivable in each of said recesses, said roller contact having an axle; a contact'carrier for said roller contact movable about said center of curvature along a carrier path concentric with and adjacent said contact path, said contact carrier having thereon cam means engageable with said axle for moving said roller contact radially out of one of said recesses in which it is disposed in response to movement of said contact carrier along said contact path, said cam means including two inclined cam surfaces which converge toward and make acute angles with said path and which are selectivelyengageable with said axle;

means, including resilient means, acting on said contact carrier said axle for biasing said roller contact into engagement with said contact path and into one of said recesses in which it is disposed in opposition to the action of said cam means; actuating means movable about said center of curvature for moving said contact carrier along said carrier path; means providing a lost-motion connection between said actuating means and said contact carrier; and kicking means carried by said actuating means and engageable with said contact carrier for limiting the lost motion between said actuating means and said contact carrier so as to kick said roller contact out of one of said recesses in which it is disposed.

6. In a rotary switch, the combination of: an arcuate contact path having a center of curvature and having circumferentially spaced recesses therein and having thereon at least one stationary contact in which one of said recesses is formed; a roller contact engaging and rollable along said contact path and receivable in each of said recesses, said roller contact having anaxle; a contact carrier for said roller contact movable about said center of curvature along a carrier path concentric with and adjacent said contact path, said contact carrier having thereon cam means engageable with said axle for moving said roller contact radially out of one of said recesses in which it is disposed in response to movement of said contact carrier along said contact path, said cam means including two inclined cam surfaces which converge toward and make acute angles with said path and which are selectively engageable with said axle; means, including resilient means, acting on said contact carrier and said axle for biasing said roller contact into engagement with said contact path and into one of said recesses in which it is disposed in opposition to the action of said cam means; actuating means movable about saidcenter of curvature for moving said contact carrier along said carrier path; means providing a lost-motion connection between said actuating means and said contact carrier, said lost-motion connection including means providing relative rocking movement between said actuating means and said contact carrier; and kicking means carried by said actuating means and engageable with said contact carrier for limiting the lost motion between said actuating means and said contact carrier so as to kick said roller contact out of one of said recesses in which it is disposed.

7. In a rotary switch, the combination of: an arcuate contact path having a center of curvature and having circumferentially spaced recesses therein and having thereon at least one stationary contact in which one of said recesses is formed; a roller contact engaging and reliable along said contact path and receivable in each of said recesses, said roller contact having an axle; a contact carrier for said roller contact movable about said center of curvature along a carrier path concentric with and adjacent said contact path, said contact carrier having thereon cam means engageable with said axle for moving said roller contact radially out of one of said recesses in which it is disposed in response to movement of said contact carrier along said contact path, said cam means including two inclined cam surfaces which converge toward and make acute angles with said path and which are selectively engageable with said axle; means, including resilient means, acting on said contact carrier and said axle for biasing said roller contact into engagement with said contact path and into one of said recesses in which it is disposed in opposition to the action of said cam means, said resilient means including torsion springs carried by said contact carrier and each having an arm engaging said contact carrier and another arm engaging said axle; actuating means movable about said center of curvature for moving said contact carrier along said carrier path; means providing a dost-motion connection between said actuating means and said contact carrier, said lost-motion connection including means providing relative rocking movement between said actuating means and said contact carrier; and kicking means carried by said actuating means and engageable with said contact carrier for limiting the lost motion between said actuating means and said contact carrier so as to kick said roller contact out of one of said recesses in which it is disposed.

8. In a switch, the combination of: a structure providing a contact path having spaced recesses therein and having thereon at least one stationary contact in which one of said recesses is formed; a contact carrier movable along a carrier path adjacent said contact path; actuating means pivotable relative to said structure about a pivot axis for moving said contact carrier along said carrier path; a roller contact carried by said contact carrier and engaging and rollable along said contact path and receivable in each of said recesses; means, including resilient means, for biasing said roller contact into engagement with said contact path; and cam means for moving said roller contact out of one of said recesses in which it is disposed in response to movement of said actuating means about said pivot axis.

9. In a switch, the combination of: a structure providing a contact path having spaced recesses therein and having thereon at least one stationary contact in which one of said recesses is formed; a contact carrier movable along a carrier path adjacent said contact path; actuating means pivotable relative to said structure about a pivot axis for moving said contact carrier along said carrier path; a roller contact carried by said contact carrier and engaging and reliable along said contact path and receivablein each of said recesses; means, including resilient means, for biasing said roller contact into engagement with said contact path; means providing a lostmotion connection between said actuating means and said contact carrier; and cam means for moving said roller contact out of one of said recesses in which it is disposed in response to movement of said actuating means about said pivot-axis.

a 10. A switch'according to claim 9 wherein said roller contact isprovided with an axle and wherein said cam means is engageable with said axle.

No references cited.

Images